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63,224
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Further characterization of protein A reactive and non-reactive subfragments of Fc from human IgG.
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Tryptic digests of acid-treated Fc from normal human IgG were separated into four peaks (I-IV) by gel filtration on Sephadex G-100. The second peak was further divided into two fractions (II and II'). Peak I was indistinguishable from intact Fc on electrophoresis, immunodiffusion, and reactivity to protein A. The protein A reactive fragments of fractions II, II', and III were shown to contain antigenic determinants of both the CH2 and CH3 domains, to interact with the anti-Gm (1) specific rheumatoid factor, and to fix complement. These results, together with SDS-electrophoresis, showed that protein A reactive fragments are all composed of an intact Fc chain with shorter chains covalently linked to it. The protein A non-reactive fragments of fractions II' and III were homogeneous, fixed complement and showed no interaction with the Gm (1) rheumatoid factor. These results, in addition to the observed antigenic determinants, localized the fragments to the CH2 region.
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63,225
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Antigenic properties of a DNA-preparation from calf thymus used for the demonstration of anti-DNA.
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It was attempted to evaluate passive haemagglutination of antigen coated, tanned erythrocytes as a test by which to demonstrate anti-DNA in systemic lupus erythematosus. The antigens was prepared using a minimum of procedures in order to produce a native preparation. The resulting material had most of the criteria applying to native DNA, but the protein content was about 9%. It contained a thymocyte specific component, but no demonstrable trace of bovine species antigen. The reactions between the antigen and an anti-DNA serum from a patient with suspected SLE were inhibited by DNA and DNA-histone, but not appreciably by ENA, RNA or desoxyribonucleosides. Passive haemagglutination reactions against the antigen were positively correlated to a homogeneous immunofluorescence nuclear pattern and negatively correlated to a speckled pattern. Passive haemagglutination titres against ENA and DNA antigen were not correlated. Seventy-three per cent of randomly selected sera gave either purely DNase sensitive reactions (19%) or reactions of combined sensitivity to DNase and other enzymes. Twenty-eight out of 53 sera reacting in the passive haemagglutination test reacted also in the immunofluorescence test against Chrithidia luciliae kinetoplasts. The latter reactions were DNase sensitive. It applies to both tests that DNase sensitive, but RNase resistant, reactions were well correlated, irrespective of their sensitivity to trypsin while DNase resistant or DNase and RNase sensitive reactions were not correlated. The passive haemagglutination test using a native but relatively crude DNA-preparation coated on tanned sheep erythrocytes supplemented by specificity tests with DNase and RNase treated antigen gives about the same information as the indirect immunofluorescence test against Chrithidia luciliae kinetoplasts. Furthermore, the results show that patients' sera reacting with a homogeneous nuclear pattern in the indirect immunofluorescence test may contain not only anti-DNA and anti-nucleohistone antibodies, but also antibodies to a number of non-histone chromatin associated proteins some of which contain RNA.
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63,226
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Encephalitogenic activity of the N-terminal part of bovine myelin basic protein in rabbits.
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The disease-inducing activity of the N-terminal part (residues 1-42) of bovine myelin basic protein in rabbits is localized to two regions. One encephalitogenic determined probably incorporates at least one of the lysine residues (Nos. 4 and 11); the other is within residues 20-36. It is concluded that region 1-42 shows a comparably strong degree of encephalitogenicity for rabbits.
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63,227
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Inhibition of the mitogenicity of the carrier molecule results in loss of immunogenicity of a hapten-LPS conjugate.
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Colistin methanesulfonate, a basic polypeptide similar to polymyxin E, has been shown to suppress the mitogenicity of lipopolysaccharide (LPS) from E. coli. It also inhibits the immunogenicity of a hapten-LPS conjugate. The inhibition was neither due to interference with the expression of hapten determinants, nor was it due to crossreactivity between the hapten and colistin methanesulfonate. As mitogenicity and immunogenicity was similarly affected, we conclude that activation of bursa-derived lymphocytes, in specific thymus-independent immune responses, does not take place in the absence of a mitogenic (non-Ig mediated) signal, thus supporting the hypothesis of the "one nonspecific signal" for B cell triggering.
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63,229
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Intracellular localization of carbonic anhydrase in the frog nephron.
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The intracellular distribution of carbonic anhydrase has been studied in the frog nephron by a histochemical method. The study of the detailed intracellular localization was possible by sectioning tissue embedded in plastic (Sorwall, JB-4), before staining essentially according to Hansson. This procedure preserves the intracellular structure well and the resolution is high. For light microscopy sections from 1 to 10 mum were used. For electron microscopy 0.25 mum thick sections were stained and examined in the electron microscope using an accelerating voltage of 100 kV. The highest concentrations of the enzyme seem to be localized to the cell membranes or their immediate neighbourhood. A faint cytoplasmic staining may sometimes be observed. In distal tubule cells the apical part of the cell membrane was heavily stained. Weaker staining was found at the lateral membranes and their infoldings and to some extent the basal parts of the cell membrane. In the canaliculi cells only the lateral and basal parts of the membranes were stained. This latter localization is similar to that in the parietal cells of the mammalian stomach.
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63,236
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Radioimmunoassays for prostaglandin metabolites.
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Radioimmunoassays were developed for the main plasma and urinary metabolites of PGF2alpha in the human, viz., 15-keto-13,14-dihydro-PGF2alpha and 5alpha, 7alpha-dihydroxy-11-ketotetranorprosta-1,16-dioic acid. The methods allowed assay of unextracted samples and had a sensitivity of 5 pg and 2 pg, respectively. The assays were evaluated by comparison with mass spectrometric data. Normal levels of these metabolites were estimated in a number of subjects. Levels in plasma and urine of the metabolites were followed after injection or during infusion of PGF2alpha and during administration of various antiinflammatory drugs.
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63,237
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Studies on the characteristics of poliovirus type 3. II. Characteristics of "hot" clones.
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Markers d, IST, EA1(OH)3, rct (at sub- and supraoptimal temperatures) and neurovirulence were determined for clones isolated from two lots (S2 and S3) of vaccines containing poliovirus strain Leon 12a1b. Changes of markers rct, d and neurovirulence were observed in several clones isolated from S2 vaccine. No changes were observed in IST and EA1(OH)3 markers.
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63,238
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Electron microscopy of surface structures of Rickettsia prowazeki stained with ruthenium red.
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In studying surface structures of Rickettsia prowazeki (E and Breinl strains) by ruthenium red staining, a microcapsular layer 125-165 A thick, composed of subunits 85--100 A in diameter with a periodicity of 100--120 A as well as the inner layer of the cell wall 40--60 A thick were clearly revealed. In tangential sections of cells, subunits of the microcapsular layer were found in parallel striation arrays. These structures presumably contain acid mucopolysaccharides detectable by ruthenium red staining. Besides, hitherto unreported intracytoplasmic membrane structures were detected in ruthenium red-stained rickettsiae.
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63,241
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Histogenesis of splenic lesions in Hodgkin's disease.
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Histochemical markers were used to identify the various cellular and structural components of the human spleen, and to investigate the histogenesis of the splenic lesions of Hodgkin's disease. The early lesions appear in areas near the central artery (periarterial lymphatic sheath) in the white pulp. The white pulp becomes hypertrophic. The lesions enlarge, extend into the red pulp, and compress the sinuses and the cords of Billroth. The derivations of various "histiocytes" contained with the lesions are differentiated by using cytochemical stains for lysosomal enzymes and for granulocytes. The epithelioid cells in the granulomas are rich in those lysosomal enzymes typically seen in phagocytic histiocytes, suggesting that they are indeed true histiocytes. The malignant "histiocytes," including the mononuclear Hodgkin cells, the binucleated Sternberg-Reed cells, and the multinucleated giant cells, do not contain significant amounts of lysosomal enzymes and more closely resemble stimulated lymphocytes. The splenic lesions in Hodkin's disease may be the result of a lymphocytic and histiocytic cellular response to an unknown agent, which reaches the spleen through the central artery in the white pulp.
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63,242
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Use of retrograde cholangiography in guiding radiotherapy of obstructive jaundice due to tumor.
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A patient with oat cell carcinoma of the lung which was responsive to radiotherapy developed jaundice. Endoscopic retrograde pancreatocholangiography (ERCP) revealed compression of the distal common bile duct. Radiotherapy to this area produced prompt and prolonged relief of the obstructive jaundice. The use of ERCP which led to significant palliation in a patient with known inoperable cancer makes this case worthy of note.
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63,243
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Identification of cells in culture.
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Most laboratories using cells cultured in vitro maintain multiple cell lines. Such lines should be monitored for species and intraspecies characteristics to prevent invalidation of research work due to incidents of cell line cross-contamination. This report describes the results obtained when 246 cell cultures were examined for evidence of cross-contamination or mislabeling. Using species-specific antigens, isoenzyme electrophoresis, and chromosomes as markers of identity, 14% of the cultures submitted were found to be contaminated by cells of another species. Of human cell lines submitted 25% were of HeLa cell origin, as determined by 2 intraspecies markers, glucose-6-phosphate dehydrogenase and chromosome analyses. The fact that, overall, nearly 30% of the cell lines examined were incorrectly designated makes the importance of cell line monitoring self-evident.
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63,245
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Toxemia of pregnancy: assessment of fetal distress by urinary estriol and circulating human placental lactogen and alpha-fetoprotein levels.
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The efficacy of three biochemical methods for the detection of fetal distress was assessed in a prospective study of 224 singleton pregnancies complicated by toxemia. Fetal distress was diagnosed in 65 cases (29 per cent). Abnormally low urinary estriol (E3) excretion pointed out 63 per cent, low serum levels of human placental lactogen (HPL) 27 per cent, and elevated maternal serum alpha fetoprotein (AFP) 10 per cent of distressed fetuses. The efficacy of each test increased with the severity of maternal disease. The frequencies of false pathologic levels were: E3 19 per cent, HPL 0 per cent, and AFP 1 per cent of the cases with a normal fetal outcome. Although E3 was by far the most effective marker, abnormal levels of HPL and AFP provided supportive evidence for fetal distress by pointing out those cases in which E3 reading was not a false positive.
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63,246
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A light microscopic, autoradiographic study of axoplasmic transport in the optic nerve head during ocular hypotony, increased intraocular pressure, and papilledema.
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Cyclocryotherapy of the monkey eye reliably produces transient increased intraocular pressure followed by prolonged hypotony, during which papilledema occurs. Axoplasmic transport was studied while the intraocular pressure was both increased and decreased after cyclocryotherapy by autoradiography following the intravitreal injection of tritiated leucine and proline. Surgical fistulization of the anterior chamber was also used to produce hypotony and papilledema. Significant alterations of both the rapid and the slow components of axoplasmic transport were demonstrated in the nerve head during increased intraocular pressure, and in ocular hypotony with papilledema.
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63,247
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Pharmacologic modulation of inflammatory mediator release by rat mast cells.
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Current knowledge of the mechanism of inflammatory mediator release from mast cells is reviewed with particular reference to the role of cyclic nucleotides and calcium and their interrelationship with one another as defined by studies in highly purified rat peritoneal mast cells. Data are presented indicating an important role for intracellular cAMP and calcium in the mediation or modulation of release, as well as evidence for a close relationship between these two regulatory systems. Releasing agents which clearly act at the level of the plasma membrane (concanavalin A and anti-IgE antibody) are shown to differ from releasing agents that may not (48/80 and the ionophore A23187) in regard to the early cellular cAMP response, dependency of the release reaction on phosphatidyl serine, and kinetics of release. Pharmacologic modulators of release are discussed; these include: PGE1 and theophylline, which raise cAMP and inhibit release; and diazoxide, adenine, and carbachol which lower cAMP and potentiate release. Adenosine was also found to enhance release with marked effects at concentrations in the low nanomolar range.
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63,255
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Interaction of genes controlling two allotypes in chickens.
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This paper presents the results of the investigations of the newly detected antigen of chicken blood serum, called K2. It was established that the K2 antigen which was identified with isoimmune serum was a beta-globulin with the molecular weight over 200 000. The results of the genetic analysis based on sire-dam-offspring combinations seemed to indicate that the antigen under examination was controlled by a gene hypostatic to the gene controlling the previously described K1 allotype.
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63,256
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Removal of blood group determinants from bovine erythrocyte membranes. 3. Action of proteolytic enzymes on intact cells.
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Bovine erythrocyte treatment with chymotrypsin, trypsin, pronase, papain, or ficin eliminated or weakened the reactivity of 18 of the 47 blood group factors which were examined. Thirteen of the affected factors were from the B system, and one each was from the C, FV, L, M, and R'S' systems. Variation attributable to pheno-group (allele) or genotype influences was observed in the effects upon six of the factors. Ficin-treated V/V, but not F/V or F/F, cells were rapidly lysed by normal rabbit serum (complement control). Absorptions with pronase-treated V positive cells indicated that essentially all V antigenicity was removed. However, immunizations with pronase-treated V positive cells elicited V antibody production in one of two recipient cows. The numbers of antigens removed by different enzymes did not appear to be closely related to the amount of protein removed.
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63,257
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Alleviation of primary fibrinolysis after hypophysectomy.
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A case of primary hyperfibrinolysis secondary to disseminated prostatic carcinoma is presented. Transsphenoidal hypophysectomy resulted in a significant palliative response and reversal of the bleeding tendency.
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63,259
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Serotherapy of avian reticuloendotheliosis virus-induced tumors.
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Immune serum, obtained from animals that had survived sublethal challenge with RE virus, was very effective in achieving tumor cures in chickens infected with this virus. The therapeutic effect could also be obtained by the immunoglobulin fraction of immune serum. The serum did not influence the development of an unrelated malignancy. Serotherapy studies in Bx and Tx recipients indicate that the B-cell or T-cell system of the host does not significantly contribute to the curative activity of immune serum. Absorption studies show that the curative effect is mediated by antibodies to tumor-associated transplantation antigens on tumor cells, not by antiviral antibodies.
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63,263
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Background and practical aspects of hepatitis B surface antigen carrier state.
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The prevalence of hepatitis B surface antigen (HBSAg) carriers in the Europe and North America 0.1 - 0.2%, but can exceed a few per cent in South-East Asia and Africa. The HBSAg carrier state is considered to be connected with sociaohygienic conditions but it is evident that genetic factors also contribute the chronic carrier state. Practical measures concerning the treatment and management of HBSAg carriers are discussed.
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63,264
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Histological characteristics of chronic hepatides and primary biliary cirrhosis with special reference to orcein positive hepatocellular accumulations.
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The histological criteria of chronic hepatides (chronic persistent and aggressive hepatitis) and primary biliary cirrhosis are well characterized and documented in the literature. Histology forms the diagnostic basis for chronic hepatides. Diagnostic changes are seen, however, only in some cases of primary biliary cirrhosis (PBC) and only in the early stages of the disease. Difficulties are met especially in differentiating PBC from chronic aggressive hepatitis (CAH). There is a considerable histological overlap and mixed forms occur. Orcein-positive material, which is a copper-binding protein with high content of sulphydryl groups, accumulates in liver cells in long standing cholestatic liver diseases and can be demonstrated histochemically in routine biopsy specimens. It is seen in PBC in at least 70% of biopsy specimens which confirms the biliary nature of the disease. In CAH orcein positive material can be demonstrated in 20% of specimens but only from patients who also have features of PBC. This group of patients may therefore have both biliary disease are hepatocellular damage, and can be separated from CAH by the orcein method.
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63,265
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Clinical correlations and significance of orceinpositivity in chronic active hepatitis and primary biliary cirrhosis.
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Clinical, biochemical and immunological variables were analyzed in 30 patients with orcein-negative (ON) chronic active hepatitis (CAH), 4 patients with ON primary biliary cirrhosis (PBC), 8 patients with orcein-positive (OP; intracellular copper-binding protein seen histologically in liver biopsy specimens) CAH and 15 patients with OP-PBC. A marked elevation of serum bile acids, alkaline phosphatase, leusine aminopeptidase, gammaglutamyl transpeptidase and cholesterol concentrations, and highly pathological BSP Tm values were characteristic for OP-cases. In addition the faecal fat level was increased and bile acids decreased in OP-cases. Serum levels of IgG or IgM and the occurrence of smooth muscle, mitochondrial or glomerular antibodies were identical in ON- and OP-CAH as well as also in ON- and OP-PBC. 49 patients were treated with a combination of prednisone and azathioprine from 4 to 72 months (mean 22). 26 patients with ON-CAH responded biochemically and morphologically to the treatment. No treatment failures were found in ON-CAH. In contrast treatment failure was confirmed in every treated OP-PBC or OP-CAH. The results suggest that orcein-positivity indicates a poor response to prednisone-azathioprine treatment of CAH.
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63,266
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The prevention of viral hepatitis.
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Studies with heat-inactivated MS-2 serum have indicated that active immunization against hepatitis B infection can be achieved even though the virus has not been cultivated in tissue culture. The development of new biophysical, biochemical and immunological techniques has increased knowledge of the hepatitis B virus and its associated antigens. In the wake of these recent developments the accumulating evidence indicates that active immunization could be achieved by the use of purified hepatitis B surface antigen or by one of its polypeptides or glycolipids.
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63,267
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Method for reproducible large-volume production and purification of Rauscher murine leukemia virus.
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Rauscher murine leukemia virus was produced in roller-bottle cultures of chronically infected JLS-V9 cells. Virus from this culture fluid was concentrated and purified by two semi-isopycnic bandings in sucrose gradients. Virus material obtained from young, nonconfluent cultures (early-harvest virus) yielded products characteristically containing endogenous ribonucleic acid-dependent deoxyribonucleic acid polymerase with high specific activity (400 to 1,000 pmol of [3H]thymidine 5'-triphosphate incorporated per milligram of protein per hour). Fluids obtained from older confluent cultures (late-harvest virus) yielded products with endogenous ribonucleic acid-dependent deoxyribonucleic acid polymerase with little or no specific activity (200 pmol or less of [3H]thymidine 5'-triphosphate incorporated per milligram of protein per hour), but with higher virus particle counts and greater amounts of protein and gs antigen than the early-harvest products.
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63,268
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Penetration and comparative metabolism of leptophos in susceptible and resistant houseflies.
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The metabolism and rate of penetration of leptophos (O-methyl O-4-bromo-2,5-dichlorophenyl phenylphosphonothioate) was determined in a susceptible strain and a strain of housefies which was 50-fold resistant to leptophos. Penetration of leptophos into resistant flies was substantially slower than into susceptible flies but large differences in metabolism, both quantitatively and qualitatively, were not observed. No difference was observed in the sensitivity of flyhead and thorax acetylcholinesterase to leptophos-oxon in vitro, and tolerance to leptophos by the resistant strain is explained in terms of decreased rates or penetration and minor differences in metabolism.
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63,269
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Insecticide movement following application to crevices in rooms.
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The movement of chlorpyrifos and diazinon from cracks and crevices in empty dormitory rooms with and without forced air movement to houseflies and plates in non-target areas was studied. Aluminum pie plates in rooms with the high concentrations of an insecticide, no forced air movement, and at the earlier sampling interals contained more insecticide. Insecticides were not detectable at 48 hr. Increased housefly movement occurred simultaneously with the initiation of insecticide application in rooms with forced air and 1 min later in rooms with no forced air. Mortality of houseflies exposed during and at 5 hr after insecticide application was greater for males than females in all tests except one; at the high insecticide concentrations; and at successive time intervals through the 24-hr interval after their transfer from the treated rooms to holding rooms. Houseflies in cages near the ceiling, exposed to an insecticide, and forced air movement, exhibited greater mortality than those in cages on the floor, while the reverse was true for houseflies in rooms with no forced air movement.
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63,270
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The evolution of the concept of the use of surgical castration in the palliation of breast cancer in pre-menopausal females.
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The understanding of the association of mammalian ovarian function with lactation was common knowledge to dairy-men early in the 19th century or earlier. This thesis reviews the application of these empiric observations to lactation in humans by Beatson of Glasgow, supported by his preliminary laboratory investigations. Beatson noted the cellular anatomic similarity between pre-gestational breast and carcinoma. This study reviews the progressive development of the successful clinical application of castration for the control of inoperable breast cancer by Beatson in pre-menopausal women in 1895. The review terminates with its leading to the monumental work of Huggins in 1941.
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63,271
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Palliation of infants with truncus arteriosus through creation of a pulmonary artery ostial stenosis.
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A surgical procedure for palliation of infants with truncus arteriosus and excessive pulmonary blood flow (types I, II, and III) is described. The technique involves the production of ostial stenosis of the pulmonary artery from within the truncus using cardiopulmonary bypass. This method has advantages over pulmonary artery banding, which in general has produced disappointing results.
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63,272
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[Effect of long-lasting noise on the plasma concentration of catecholamines, glucocorticosteroids and PBI in pigs].
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Exposure of pigs with a body mass of 25-30 kg to long-lasting motor noise (108 dB, 60-8000 Hz, 72 hours) results in a considerable increase of catecholamine concentration in the plasma. Coincidently there is a sharp continuous decrease of the 11-OHKS in the plasma during the whole period of exposure to noise. Immediately after stopping the acoustic irritation the concentration of plasma corticosteroids increases again. The electroencephalogram (EEG) giving evidence of inhibition signs during exposure to noise an adaptation effect of the information processing system is concluded. The increase of the PBJ during the period of acoustic stress points to an increased function of the thyroid gland but simultaneously it is considered to be an expression of the elevated adrenergic situation. By reason of the strong deviation of the three observed regulatory systems must be concluded that longer-lasting exposure to noise with the applied quality and intensity represents a stress situation for pigs having noise character as established for men. A possible influence on the productivity of the pork type pig by permanent acoustic stress is indicated.
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63,273
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Conditions favoring immunological enhancement of a murine allogeneic lymphoma.
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An in vivo model was used which permits the growth of AKR lymphoma allografts inoculated within a glass cylinder subcutaneously implanted in BALB mice. Pretreatment of the host with acellular tumor extracts or tumor cells enclosed within a diffusion chamber significantly increased tumor incidence. On the contrary, donor spleen extracts did not alter tumor incidence while viable spleen cells within a diffusion chamber even prevented tumor development. It can be concluded that in this model a condition of maximal tumor enhancement can be attained with soluble tumor antigen but not with normal spleen extracts.
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63,274
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Primary immune response to sheep red blood cells in mice treated with immunoregulatory alpha-globulins (IRA).
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Alpha-Globulins from human and bovine sera or from mouse ascitic fluid were separated by ion-exchange chromatography on DEAE-cellulose into fractions A, B, and C. Fractions A and B had no immunosuppressive activity; fraction C injected into mice at the time of antigen administration, but not later, significantly reduced the number of anti-SRBC plaque-forming cells in the spleens of experimental animals. Single high dose inhibited the response better than the same doses given on 4 consecutive days. It is concluded that a critical level of alpha-globulins is necessary to render lymphocytes hyporesponsive, and when once stimulated by antigen they become less susceptible to alpha-globulin action.
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63,275
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Anti B and T cell activity of antiserum to spleen cells of athymic (nu/nu) mice: evidence for surface antigenic differences between functionally distinct subclasses of T and B lymphocytes.
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A rabbit antiserum obtained by immunization with spleen cells of nu/nu mice, known to be deficient in thymus and T cells but not in T cell precursor, possesses two different specificities. In addition to activity against bone marrow-derived lymphocytes (B cells), as revealed by inhibition of antibody forming cells and myeloma cells, the antiserum (Ra-nu/nu) has strong activity against cytotoxic T cells but not against helper T cells. Differences in sensitivity to antiserum treatment between anatomically and functionally distinct B cells point to surface antigenic differences among subclasses of B cells.
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63,276
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Comparative study of the electrophoretic mobility of the RNA of influenza parent and recombinant strains.
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The electrophoretic mobility of the RNA of Influenza viruses A/WSN, A/Singapore and their antigenic recombinants X-7 and X-9 was investigated. The genome of each virus studied consisted of seven pieces of RNA. The electrophoretic profile of the influenza virus A/WSN RNA differed from that of A/Singapore but resumbled that of the recombinant X-9 genome. The essential differences were connected with the properties of the fifth fragment of the RNA. The molecular weight of this RNA species of influenza virus A/WSN and X-9 was 5.4 X 10(5) AND 5.3 X 10(5) daltons (d) respectively. The molecular weight of the corresponding component of the influenza viruses A/Sinapore and X-7 RNA was 6.2 X 10(5) and 6.3 X 10(5)d respectively.
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63,278
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A continuous-wear hydrophilic lens. Prophylactic topical antibiotics.
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Seventeen patients, who were fitted with a continuous-wear hydrophilic lens for 12 weeks, received topical neomycin sulfate-polymyxin B sulfate-gramicidin (Neosporin) eyedrops in one eye only at a frequency of 3.7 times per day. The continuous wear of a hydrophilic lens in and of itself did not after normal bacterial flora, and the use of the antibiotic drops did not alter normal conjunctival flora. In addition, the eyedrops were not more effective when used in conjunction with the hydrophilic lens and did not appear to produce resistant organisms during the 12-week study. In normal eyes, a continuously worn hydrophilic soft contact lens that is well tolerated does not adversely affect the bacterial flora and the addition of neomycin sulfate-polymixin B-gramicidin drops at a frequency of 3.7 times per day does not appear to be beneficial or necessary.
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63,277
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Effect of Ca++ on the stability of influenza virus neuraminidase.
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The neuraminidases of different strains of influenza virus varied in their stability at 37 degrees C. The enzymes of the strains with N1 neuraminidases were found to be unstable during incubation at 37 degrees C whereas the enzymes of the strains with the N2 neuraminidases were stable. Among the strains with N2 neuraminidases, the enzymes of some strains were inactivated during dialysis at 37 degrees C whereas the enzymes of others were stable. This observed loss of enzyme activity during dialysis at 37 degrees C was not restricted to a single substrate as the same loss of enzyme activity was observed irrespective of the size of the substrate used in the assay. The enzymically inactive neuraminidase was found to be non-antigenic and non-immunogenic. The inactivation of the enzyme could be prevented by the addition of Ca++ but not Mg++. Out results suggest that Ca++ is essential for the stability of the enzyme at 37 degrees C. The results would also suggest that the enzymic, antigenic and immunogenic sites are either the same or very closely situated on the surface of the neuraminidase molecule.
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63,279
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Density of mucous glands in the normal adult nasal septum.
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The entire mucosa from 13 normal nasal septa was stained by the PAS-alcian blue whole-mount method, and the mean density of glandular orifices in 13 localities was determined quantitatively by counts in 4 mm2 fields. The median density within the entire material was 8.4 glands/mm2, with an interindividual variation of +/- 1 gland/mm2. The median number was 15,900 glands, range 10,800-21,800. The distribution of the glands is regular, with little variation between the localities. Density is somewhat, but significantly lower in the posterior quarter of the septum, and there was a significant increase in density into the infero-superior direction.
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63,280
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[Meatoplasty with allogenic preserved cartilage. Histomorphological model in animal experiments (author's transl)].
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The reconstruction of the posterior wall of the external acoustic meatus destroyed by surgery or a cholesteatoma is necessary for the complete restoration of function. For this purpose, allogen cartilage preserved in thiomersalate has been transplanted on the anterior wall of the air-containing mastoid bone in 160 clinical cases. The histomorphological reaction of the recipient to unilaterally uncovered transplant material has previously been unknown. In 10 guinea pigs, 15 fenestrated bullae (hypotympanum equivalents) were closed with cartilage transplants fixed in place with tissue adhesive. After a period varying between 7 1/2 and 11 months, the walls of the bullae with the transplant were then examined histomorphologically. Despite the variations in the period in situ, the avital cartilage transplant, which remained largely constant in volume and shape, was always to be found. It was tolerated without reaction and was "enveloped"--also on the primarily uncovered surface--by a capsule of bone and connective tissue. In no case was rejection observed. Marked foreign-body reaction was, however, found in the vicinity of the tissue adhesive, which was absorbed only slowly. The clinically well-known tissue-compatible and complication free behaviour of the allogenic cartilage transplant preserved in thiomersalate, is thus explained by the histomorphological findings. In contrast, the fact that marked foreign-body reaction was demonstrable even after almost one year, suggests that tissue adhesive should not be used.
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63,281
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The conquest of smallpox.
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Smallpox has been a dreaded disease for thousands of years. Recurrent epidemics traversed the known world leaving a trail of death, disfigurement, and disability unparalleled by the other great plagues. Fear of smallpox provoked the first important attempts to prevent epidemic disease by a primitive form of immunization called variolation. In 1796, Edward Jenner developed the first effective vaccine against an infectious disease by using cowpox virus to prevent subsequent infection with smallpox. The discovery of this vaccine made possible the conquest of smallpox, a task that will probably be completed this year.
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63,287
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Kinetic studies of drug-dinucleotide complexes.
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Three classes of kinetic behavior are observed in the complexes of actinomycin or ethidium with deoxydinucleotides. First, the initial dinucleotide binding to form a 1:1 complex is a rapid bimolecular process, whose rate could be measured for combination of actinomycin with d(pTpG) d(pGpT), d(pGpA), d(pGpG) d(pCpGpG), and d(pCpG) andfor combination of ethidium with d(pGpC). Second, with one exception, all reactions in which a second dinucleotide is added to form a 2:1 dinucleotide-drug complex are limited by a first-order step at high concentration. This class includes the combination of actinomycin with all dinucleotides tested except d(pGpC), and the reaction of ethidium with nucleotides of complementary sequence pyrimidine-purine, such as d(pCpG). The final class is the special case of d(pGpC) interacting to form a 2:1 complex with actinomycin. Third-order kinetics is observed, with no evidence for a first-order, rate-limiting step.
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63,286
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Quantitation of casein messenger ribonucleic acid sequences using a specific complementary DNA hybridization probe.
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Two highly purified rat casein mRNA fractions were used as templates to synthesize complementary DNA (cDNA) hybridization probes using RNA-directed DNA polymerase isolated from avian myeloblastosis virus. Both of the probes selectively hybridized to RNA isolated from lactating mammary tissue, but not to poly(adenylic acid)-containing rat liver RNA. An analysis of the kinetics of hybridization of the cDNA derived from the 15S casein mRNA (cDNA12S) with their individual mRNA templates indicated that greater than 90% hybridization occurred over a R0t range of one and one-half logs with R0t 1/2 values of 0.0023 and 0.0032 mol s l.-1, respectively. Compared with the total RNA isolated from lactating mammary tissue, these values represented a 166- and 245-fold purification, respectively, of these individual mRNA fractions. Using the 15S casein mRNA as a template, two probes of different lengths and specific activities were synthesized. The deoxyribonucleotide and mRNA concentrations and the temperature of incubation were optimized to obtain either a high specific activity cDNA probe, 330 nucleotides long, which represented approximately 25% of the mRNA or a lower specific activity preparation containing some complete cDNA copies, 1300 nucleotides in length. The Tm of the longer cDNA15S-15S mRNA hybrid was 88.5 degrees C, while that of the short cDNA15S-RNA hybrid was 82.5 degrees C. Following this initial characterization, the cDNA15S probe was utilized for three separate determinations: (1) Analysis of the sequence divergence between mouse and rat casein mRNAs. It was observed that the rate of hybridization of heterologous rat cDNA15S-mouse casein mRNA was only 20% that of the homologous rat cDNA15S-rat casein mRNA hybridization. The resulting heterologous hybrid displayed approximately 17% mismatching compared with the homologous hybrid. (2) Determination of the gene dosage for casein mRNA in normal and malignant mammary cells. In this study, an analysis of the kinetics of hybridization of the high specific activity cDNA15S probe with an excess of DNA isolated from lactating mammary tissue, carcinogen-induced mammary tumors, or rat liver indicated that casein mRNA was transcribed from the nonlification or deletion was observed during tumor formation or the process of mammary differentiation. (3) Quantitation of casein mRNA sequences during normal mammary gland development. RNA excess hybridizations were performed using RNA extracted from either pregnant, lactating, or regressed rat mammary tissue. The concentration of casein mRNA molecules/alveolar cell was found to increase 12-fold from 5 days of pregnancy until 8 days of lactation and then declined to approximately 2% of the maximal level of 79 000 molecules/cell by 7 days after weaning. A coordinate increase was observed in casein mRNA sequences detected by cDNA hybridization and mRNA activity measured in a cell-free translation assay.
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63,290
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Circular dichroism of intermediate subviral particles of reovirus. Elucidation of the mechanism underlying the specific monovalent cation effects on uncoating.
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1. Circular dichroic (CD) spectra of purified intermediate subviral particles of reovirus were determined in the presence of different monovalent cations. 2. The CD spectra reveal that reo intermediate subviral particles can exist in two conformationally different forms. The two forms are readily distinguished by comparison of their ellipticities in the wavelength regions 210 nm and 220 nm, with a Na+-induced form exhibiting a reduced negative ellipticity relative to a Cs+-induced form. 3. The transition between the Na+- and Cs+-induced forms is reversible by manipulation of the species of monovalent cation present and appears to be temperature independent. 4. Temperature variation studies on dilute suspensions of particles indicate that the Na+-induced form is stable, whereas the Cs+-induced from undergoes a second transition, temperature dependent and irreversible, to become a viral core. 5. A model is presented relating these observations to the known properties of reovirus uncoating and transcriptase activation.
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63,289
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Anthroyl stearate as a fluorescent probe of chloroplast membranes.
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1. A reversible light-induced enhancement of the fluorescence of a "hydrophobic fluorophore", 12-(9-anthroyl)-stearic acid (anthroyl stearate), is observed with chloroplasts supporting phenazine methosulfate, cyclic or 1,1'-ethylene-2,2'-dipyridylium dibromide (Diquat) pseudo-cyclic electron flow; no fluorescence change is observed when methyl viologen or ferricyanide are used as electron acceptors. The stearic acid moiety of anthroyl stearate is important for its localization and fluorescence response in the thylakoid membrane, since structural analogs of anthroyl stearate lacking this group do not show the same response. 2. This effect is decreased under phosphorylating conditions (presence of ADP, Pi, Mg2+), and completely inhibited by the uncoupler of phosphorylation NH4Cl(5-10mM), as well as the ionophores nigericin and gramicidin-D (both at 5 - 10(-8)M). The MgCl2 concentration dependence of the anthroyl stearate enhancement effect is identical to that previously observed for cyclic photophosphorylation, as well as for the formation of a "high energy intermediate". The anthroyl stearate fluorescence enhancement is inhibited by increasing concentrations of ionophores in parallel with the decrease in ATP synthesis, but is essentially unaffected by specific inhibitors (Dio-9 and phlorizin) of photophosphorylation; thus, it appears that anthroyl stearate monitors a component of the "high energy state" of the thylakoid membrane rather than a terminal phosphorylation step. 3. The light-induced anthroyl stearate fluorescence enhancement is suggested to monitor a proton gradient in the energized chloroplast because (a) similar enhancement can be produced by sudden injection of hydrogen ions in a solution of anthroyl stearate; (b) when the proton gradient is dissipated by gramicidin or nigericin light-induced anthroyl stearate fllorescence is eliminated; (c) when the proton gradient is dissipated by tetraphenylboron, light-induced anthroyl stearate fluorescence decreases, and (d) light-induced anthroyl stearate fluorescence change as a function of pH is qualitatively similar to that observed with other probes for a proton gradient (e.g. 9-aminoacridine). Furthermore, anthroyl stearate does not monitor H+ uptake per se because (a) the pH dependence of H+ transport is different from that of the anthroyl stearate fluorescence change, and (b) tetraphenylboron, which does not inhibit H+ uptake, reduces anthroyl stearate fluorescence. Thus, anthroyl stearate appears to be a useful probe of a proton gradient supported by phenazine methosulfate of Diquat catalyzed electron flow and is the first "non-amine" fluorescence probe utilized for this purpose in chloroplasts.
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63,292
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Purification and characterization of gibbon ape leukemia virus DNA polymerase.
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An RNA directed DNA polymerase was purified over 2500 fold from gibbon ape leukemia virus by successive column chromatography on Sephadex G100, DEAE cellulose, phosphocellulose and hydroxyapatite. The purified DNA polymerase has a molecular weight of 68 000, a pH optimum of 7.5, a Mn2+ optimum of 0.8 mM, and KCl optimum of 80 mM. The purified enzyme transcribes heteropolymeric regions of viral 60-70 S RNA isolated from avian myeloblastosis virus, Rauscher murine leukemia virus and simian sarcoma virus and it is inhibited by antiserum prepared against either gibbon ape leukemia virus or simian sarcoma virus DNA polymerases.
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63,293
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Interaction of rifamycins with mammalian nucleic acid polymerizing enzymes.
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Procedures were established for the isolation and partial purification of DNA polymerase, RNA polymerase and poly(A) polymerase activities from the cytoplasm and nuclei of NIH-Swiss mouse embryos. Based on the elution pattern of these enzyme activities from DEAE-cellulose and phosphocellulose columns in Tris-HCl buffer, pH 8.0, the apparent basicities of the enzymes can be arranged as follows: cytoplasmic(C) poly(A) polymerase greater than (C)DNA polymerase beta greater than (C)DNA polymerase alpha and nuclear(N) poly(A) polymerase greater than (N)DNA polymerase greater than (N)RNA polymerase I greater than (N)RNA polymerase II. Twenty rifamycins, including rifamycin B, rifamycin S, rifamycin SV, and rifamycin SV derivatives, were examined for their ability to inhibit the above mentioned nucleic acid polymerizing enzymes and Simian sarcoma virus type I (SSV-1) reverse transcriptase. Rifamycin SV 3'-formyldiphenylhydrazone, rifamycin SV 3'-formyl-n-octyloxime (AF/013) and rifamycin SV 3'-formyldiphenylmethyloxime (AF/05) inhibited all the tested enzyme activities. Rifamycin SV 3'-formylpropylphenyloxime (AF/015) inhibited cellular nucleic acid polymerase activities but not SSV-1 DNA polymerase activity. Rifamycin SV 3'-formyldinitrophenylhydrazone (AF/DNFL) strongly inhibited reverse transcriptase activity but did not inhibit cellular DNA polymerase activities. AF/DNFI slightly inhibited RNA and poly(A) polymerase activities. Rifamycin SV 3'-formyldipropylhydrazone (AF/DPI) and 2,6-dimethyl-4-N-benzyldemethyl-rifampicin (AF/ABDMP) slightly inhibited reverse transcriptase activity but did not inhibit cellular nucleic acid polymerase activities. Active rifamycin derivatives inhibited enzyme reactions by interacting with the enzyme proteins. Nascent polynucleotide chain elongation continued although at a reduced rate in the presence of inhibitor. The addition of increasing concentrations of nonionic detergent (Triton X-100) to rifamycin-inhibited enzyme reactions fully restored enzyme activities. The presence of highly lipophilic 3'-side chains on active rifamycins and the reversibility of enzyme inhibition by Triton X-100 suggest that the tested nucleic acid polymerizing enzymes may have hydrophobic regions with which inhibitory rifamycins interact.
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63,294
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A new estimate of human ribosomal gene number.
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Radioactively labelled DNAs (5 X 10(6) cpm/mug) complementary to human 18 S and 28 S ribosomal RNA were synthesized using RNA-directed DNA polymerase (EC 2.7.7.7). These complementary DNAs were used to measure human ribosomal gene numbers by two independent methods, both of which indicated numbers at least four-fold lower than those previously reported. First, the kinetics of the annealing of the complementary DNAs with total human placental DNA indicated that the number of both 18-S and 28-S ribosomal genes per haploid genome is approximately 50. Second, saturation experiments in which a constant amount of DNA was annealed with increasing amounts of complementary DNA also indicated that the number of 28 S ribosomal RNA genes in human placental and spleen DNA is is about 50 per haploid genome.
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63,297
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Antibody-like activity to polyacrylic acid in normal rabbit sera.
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Most unimmunized rabbit sera agglutinate acrylic particles coated with polyacrylic acid. The factor responsible for the agglutinating activity turned out to be a 2-mercaptoethanol-resistent immunoglobulin, present in low concentration. It was tentatively classified as "natural antibody". This is assumed to have arisen upon previous contact with naturally occurring cross-reacting polyanions.
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63,296
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Latent homology of murine lymphoid antigens revealed through the complement mediated absorption of xenogeneic antiserum.
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Xenoantiserum against C57BL/6 mouse spleen cells was produced by immunization of rabbits. Such antiserum displayed cytotoxic activity for several strains of mice. Standard "in vitro" absorption removed species specific antibody revealing antibody directed against the C57BL/6 strain. When the xenoantiserum was absorbed with DBA/2 spleen cells in the presence of complement, the binding of anti-C57BL/6 was increased. Such data suggest that xenoantibodies directed against spleen cells possess a broader capacity to react with cross-strain lymphoid antigens than previously described.
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63,298
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Urinary excretion of total protein, albumin and beta2-microglobulin during exercise in adolescent diabetics.
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Urinary total protein, albumin and beta2-microglobulin excretion during exercise on a bicycle ergometer was determined in a group of 7 adolescent male diabetics and in a comparable control group. There was no difference, neither in the diabetic group nor in the control group, in the excretion of these proteins under the provocative effect of physical exercise. These results suggest exercise may not always give a positive response and is not a discriminative function in reliable studies of renal function.
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63,299
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Leukocyte cytochemical reactions in preterm and small for date babies.
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Four cytochemical reactions widely used for hematological diagnosis (Myeloperoxydase, leukocyte alkaline phosphatase, PAS and Sudan Black) were carried out in 46 infants admitted into a neonatology unit (14 preterm babies, 19 small for date newborn infants (SDB) and 13 preterm with retarded intra-uterine growth). The MPO, polymorphonuclear PAS and Sudan Black levels are comparable in the three groups of infants and the same as in normal full-term newborn babies. On the other hand, the LAP level, identical in preterms and SDB, is lower than in full-term infants but higher than in adults. Lymphocyte PAS value increases progressively with age. Better interpretation of results would be gained with knowledge of normal ranges for these four parameters in children. The authors suggest that these reactions should be used in the field of general metabolic diseases, susceptibility to infection and genetic diseases with or without chromosal abnomaly.
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63,301
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[Isolation and characterization of pregnancy associated alpha2 glycoprotein].
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A method using immunoadsorbents for the isolation of pregnancy-associated alpha2-glycoprotein (alpha2-PAG) from the extract of human placentae is described. The physical properties and the chemical composition of the purified protein are determined: alpha2PAG sediments with 11,5 S, has a molecular weight of 360 000 daltons and is composed of subunits having a molecular weight of 180000, which are held together by disulfide bonds. The isoelectric point was found to be pH 4,7 and the extinction coefficient (E1%1cm) was determined to be 9,7 at 277 nm. The carbohydrate content of the molecule amounts to 12,1% (hexose 6,0%, hexosamine 3,7%, fucose 0,06%, sialic acid 2,4%). An analysis of the amino acids is reported, too. The purified alpha2PAG was used to determine the absolute concentrations of this protein in a reference standard and in sera.
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63,303
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Joint air pollution sampling program in twin cities on the U.S.-Mexico border.
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Ciudad Juárez (Chihuahua) and El Paso (Texas), two cities on the U.S.-Mexico border, form a single environmental system in which the same natural resources, especially air and water, are shared. It also constitutes a single metropolitan area which is characterized by high rates of pipulation growth, economic development, and urban expansion, all these factors mitigating against air quality. Early in 1972 the health authorities in El Paso and Ciudad Juárez initiated a joint air pollution sampling program with assistance from the Pan American Health Organization. The nearby city of Las Cruces (New Mexico) was later included in the program as well. Activities are carried out in accordance with a document entitled "Bases of Cooperation." The guiding criteria of the program are: functional simplicity, operational economy, and complementarity with other sampling programs conducted by the participating services. An Air Pollution Control Subcommittee is responsible for execution coordination of the program. Three studies are currently underway to determine levels of dust pollution in the air. A fourth study is aimed at measuring sulfur dioxide levels through the use of sulfation plates. The results collected reveal concentrations of particulates in the ambient air levels higher than the U.S. Federal primary standards. The program should be expanded to include the study of other pollutants and a joint inventory of emissions. In this way criteria on air quality may be established and joint plans of action and strategies drawn up for the control of air pollution in this important area.
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63,304
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Pharmacological properties of N-(3',4'-dimethoxycinnamoyl) anthranilic acid (N-5'), a new anti-atopic agent.
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1 N-(3'-4'-dimethoxycinnamoyl) anthranilic acid (N-5') exhibited a dose-dependent, potent inhibition of the passive cutaneous anaphylaxis (PCA) mediated by homocytotropic antibodies (HTA), which was hardly affected by anti-inflammatory agents such as phenylbutazone, indomethacin and prednisolone at any dose used. The HTA-induced PCA was significantly inhibited by combined treatment with diphenydramine and cyproheptadine. 2 Doses of N-5' which potently inhibited HTA-induced PCA inhibited only slightly the heterologous PCA produced by anti-bovine serum albumin (BSA) rabbit serum. This heterologous PCA was clearly inhibited by phenylbutazone, indomethacin and prednisolone. Diphenydramine and cyproheptadine, singly or combined inhibited the heterologous PCA only slightly. 3 The increased vascular permeability caused by histamine and 5-hydroxytryptamine was significantly inhibited by diphenyldramine or cyproheptadine, but not by N-5' and the anti-inflammatory agents used. 4 N-5' 150 mg/kg orally inhibited rat paw oedema induced by carrageenin by about 26% while phenylbutazone, indomethacin and prednisolone produced significant inhibition. 5 N-5' at concentrations of 100 and 1000 muM significantly inhibited (by about 52% and 95%, respectively) the histamine release from rat peritoneal cells induced by HTA; 10 muM N-5' had little effect. Histamine release was inhibited by phenylbutazone or indomethacin at 1000 muM but not at 100 muM. Prednisolone had no effect on histamine release at any of the concentrations used. 6 These findings suggest that the inhibition of the HTA-induced PCA by N-5' may be due to inhibition of histamine release and is clearly different from the actions of anti-inflammatory agents such as phenylbutazone, indomethacin and prednisolone.
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63,302
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Clinical use of combined bleomycin and radiation therapy for head and neck tumours and testicular cancers.
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The Bleomycin advantages are resumed with special reference to the use in combination with irradiation. More vigorous effect were seen in patients given Bleomycin one hour before irradiation twice to three times weekly than after irradiation alone. For head and neck tumours the effect of two weeks Bleomycin treatment alone showed 40 per cent distinct shrinkage and in this group 73 per cent of the patients were tumour-free after a full course of radiotherapy, compared to 38 per cent in the group showing no response to Bleomycin-pretreatment. Moderately differentiated squamous cancer showed just as good response as highly differentiated tumours. The one year survival using subsequent treatment of Bleomycin and irradiation, compared to an historical material showed improved survival rate for T3 laryngeal cancers, as well as all stages of testicular carcinomas given simultaneous Bleomycin twice weekly under the full course of postoperative irradiation to regional lymph nodes.
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63,306
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Efferent connections of the septal area in the rat: an analysis utilizing retrograde and anterograde transport methods.
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Experiments were performed by either retrograde (horseradish peroxidase histochemistry) or anterograde ([3H]leucine radioautography) transport methods to determine the efferent connections of the septum in the rat. It was observed that the dorsal septum projects to the lateral preoptic area, lateral hypothalamus, periventricular hypothalamus and midline thalamus. Fibers from the ventral half of the septum project topographically to the hippocampal formation, thalamus, hypothalamus and midbrain. Specifically, neurons located along the midline in the vertical limb of the diagonal band project through the dorsal fornix to all CA fields of the dorsal hippo campus and adjacent subicular cortex. Other fibers from this region project through the stria medullaris to the medial habenular nucleus and anteromedial nuclhe pars posterior of the medial mammillary nucleus. Cells located immediately lateral to the midline in the vertical limb of the diagonal band project through the medial part of the fimbria to all CA fields of the posterior hippocampus and adjacent subicular cortex. Other fibers which originate from this region project through the stria medullaris to both the medial and lateral habenular nuclei and the paratenial nucleus of the thalamus, and through the medial forebrain bundle to the pars posterior of the medial mammillary nucleus. Cells located in the intermediolateral septum project through the lateral part of the fimbria to all CA fields of the ventral hippocampus and adjacent subicular and entorhinal cortices. These cells also send fibers through the stria medullaris to the lateral habenular nucleus and mediodorsal thalamic nucleus. Other axons arising from these cells descend through the medial forebrain bundle to terminate in a region dorsal to the interpeduncular nucleus. Fibers from the most lateral part of the ventrl septum (i.e., bed nucleus of the anterior commissure) project through the stria terminalis to the ventral subiculum. In addition, cells located in the horizontal limb of the diagonal band project massively to the pars posterior of the medial mammillary nucleus and the ventral tegmental area, and amygdala.
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63,309
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Banding analysis of the somatic chromosomes of the domestic dog (Canis familiaris).
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The chromosomes of the domestic dog (Beagle) were investigated by several different staining techniques. G-banding, Q-banding, and the bis-benzimidazol derivative Hoechst 33258, make possible the identification of all 39 chromosome pairs. Constitutive heterochromatin (C-bands) was present on a few chromosomes as distinctive, large stained areas; on the other autosomes there was little or no heterochromatin detectable.
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63,310
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Differential fluorescence of sister chromatids with 4'-6-diamidino-2-phenylindole.
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Differential fluorescence of sister chromatids and sister chromatid exchanges (SCE) in chromosomes from human lymphocytes grown two replication cycles in medium containing 5-bromodeoxyuridine can be detected by fluorescence microscopy after staining with 4'-6-diamidino-2-phenylindole (DAPI). The DAPI fluorescence appears to be more stable than that of the dye 33258 Hoechst and may provide a more sensitive method for the detection of SCE.
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63,311
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Persistence of transferable drug resistance in the lactose-fermenting enteric flora of swine following antimicrobial feeding.
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Six groups of swine (85 animals) were fed a combination of antimicrobial drugs (sulfamethazine 100 g/ton, chlortetracycline 100 g/ton and penicillin 50 g/ton). After two weeks the antimicronial drugs were removed from the diet of two groups (28 animals). These swine were compared to four groups fed the medicated diet to determine the effect of duration of treatment and degree of animal isolation on the persistence of resistance in lactose-fermenting enteric organisms. The degree of resistance to penicillin, oxytetracycline, dihydrostreptomycin and neomycin as determined by minimum inhibitory concentrations and the incidence of resistant organisms were examined during and after antibiotic feedings. Ninety-two percent or greater of all isolates tested during and after treatment had minimum inhibitory concentrations for oxytetracycline of greater than 100 mug/ml. Thirty-two weeks after cessation of dietary antibiotic, resistance to oxytetracycline and dihydrostreptomycin remained at 100% and 89% respectively. Variation in degree of contact between swine receiving medicated feed and those receiving nonmedicated feed was not sufficient to reduce the incidence of resistance to oxytetracycline or dihydrostreptomycin in all animals. Factors influencing persistence of resistant enteric organisms are discussed. Addition of the antimicrobials to the ration resulted in significantly greater weight gains for treated animals than for the controls but did not alter feed conversion.
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63,312
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Friedreich's ataxia: observations with Q and G banding of human chromosomes.
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No chromosomal anomaly was found in 15 cases of typical Friedreich's ataxia and three cases of atypical recessive ataxia studied with Q and G banding techniques. No difference between frequency of chromosomes gaps or breakages was noted amongst patients with Friedreich's ataxia and controls.
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63,313
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Living with the dying: use of the technique of participant observation.
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Through participant observation, questions concerning optimal care of dying patients and needs of their families were answered. A general surgical ward and a palliative care unit were the sites of observation. The observations support the belief that a palliative care unit, specifically designed to meet the known needs of dying patients and their families, is preferable to a general surgical ward. The main findings, of less concern in the palliative care unit than on the surgical ward, were the following: the importance of patient-to-patient support; the discomfort of sick-role behaviour; the impersonal and sometimes intimidating nature of patient care; the limitation of the patient's need (as a person) to give as well as to receive; and the value of families, student nurses and volunteers in total care. These findings emphasize the importance of personal interest in relieving the distress suffered by many terminally ill patients.
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63,314
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Phase II study of mitomycin-C, vincristine, and bleomycin in advanced squamous cell carcinoma of the uterine cervix.
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Utilizing the stathmokinetic principle of timed vincristine and bleomycin, we combined these two agents with Mitomycin-C. The dose schedule included vincristine 0.5 mg/m2 intravenously (i.v.) geginning on day 1 and repeated twice weekly for 12 weeks; each injection was followed in 6-12 hours by bleomycin 6 mg/m2 for 12 weeks. Mitomycin-C was administered as a 20 mg/m2 bolus beginning on day 2 and repeated at 6-week intervals. Thirty patients were entered into this study, 27 were fully available for response. Thirteen patients (48%) met criteria of response (greater than 50% reduction in volume of measurable tumor). Significant myelosuppression resulted from this therapy. Median leukopenia nadir was 3.8 X 10(3) cells/mm3 and median thrombocytopenia nadir was 116 X 10(3) cells/mm3. Additional toxic reactions included anemia, lassitude, anorexia, peripheral neuropath fever, and skin rash. Despite significant, but manageable, toxicity, this combination appears to represent an improvement in the chemotherapy of a traditionaly refractory solid tumor.
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63,315
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Simultaneous assays of cancer-associated antigens in various neoplastic disorders.
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Five tumor markers were measured simultaneously in serum by radioimmunoassay: carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), human chorionic gonadotrophin (HGC), the beta subunit of HCG, and Kappa casein. In a population of 935 normal subjects these antigens were undetectable or found within precise limits. In patients with tumors of various origins the rate of pathologically elevated levels was 72% at the beginning of the clinical course (194 cases). This high rate was primarily due to the simultaneous measurement of CEA, betaHCG, HCG, and casein. AFP was of little importance. The simultaneous measurement of these tumor markers may be one biochemical element of diagnosis of carcinoma, although this criterion is neither absolute nor specific, as 14.7% of patients with non-neoplastic disorders (234 cases) were positive for one antigen. In the presence of metastases (112 cases) the rate of pathologic levels of at least one antigen was increased: 86% due to CEA and casein assay at the same time as their absolute levels were increased. Surgical removal reduces the rate of positivity of these antigens to 37%. As was shown in patients with breast cancer, the rate was 10% when the tumor had been removed at Stage N- and 54% when it was removed at Stage N+. Thus, the persistence of pathologic levels could be correlated with the capacity for recurrence or metastases. Finally chemotherapy, radiotherapy, or both, do not decrease the rate of positivity of the tumor markers.
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63,316
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Carcinoid of the uterine cervix: additional observations on a new tumor entity.
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Twelve carcinoid tumors of the uterine cervix were studied. Based on the microscopic structure, they were divided into well-differentiated and poorly differentiated types. Both tumor varieties affected adult women. The clinical and gross features of these tumors were indistinguishable from those of invasive squamous cell carcinoma. Of the 12 patients, six died, four with poorly differentiated carcinoid and two with the well-differentiated type. Three patients are alive and symptom-free 9 months to 2 years after treatment; the remaining three were lost to follow-up. Microscopically, four well-differentiated carcinoids showed argyrophil cells, and ultrastructurally two had neurosecretory granules. One of the well-differentiated carcinoids resembled islet cell carcinoma and two had areas resembling medullary carcinoma of the thyroid. The poorly differentiated type of carcinoid had a histologic structure and a cell population very similar to that of the oat cell carcinoma of the lung. Of this group, four were argyrophilic, and by electron microscopy four contained pleomorphic secretory granules. It is considered that these tumors arise from the normal argyrophil cell of the cervix and are part of the group of neoplasms of the diffuse endocrine cell system (APUD).
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63,317
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Morphologic and biologic characteristics of adenoid cystic carcinoma cells of the salivary gland.
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Adenoid cystic carcinoma cells cultivated in monolayer and sponge matrix culture, or implanted on the chorioallantoic membrane (CAM) of embryonated eggs, were observed morphologically, and the glycosaminoglycan components in the tumor tissue were analyzed. This tumor tissue contained a large amount of glycosaminoglycans, composed of chondroitin 4- and 6-sulfate, heparan sulfate, hyaluronic acid, and a small amount of dermatan sulfate. In monolayer culture spindle cells proliferated vigorously as multilayer, and secreated mucinous material. In sponge matrix culture, the proliferating cells became embedded in the material produced by the cells themselves. A trace of fine fibers stained with orceine was observed in the intercellular material in culture. Histologic sections of the implants grown on CAM showed that the tumor cells arranged in various structures produced a large amount of mucinous material that spread into the stromal area without any contribution from the mesenchymal element. The morphologic and biologic characteristics of these tumor cells are quite similar to those of pleomorphic adenoma.
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63,318
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Endodermal sinus tumor of the ovary: a clinical and pathologic analysis of 71 cases.
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The clinical and pathologic features of 71 endodermal sinus tumors of the ovary were studied in an effort to delineate the histogenesis and biologic behavior of this neoplasm and to evaluate the efficacy of different forms of treatment. Alpha-fetoprotein (AFP) was identified in hyaline droplets, cell cytoplasm, and intercellular spaces of all 15 tumors examined by an immunoperoxidase technique; this supports the view that the neoplasm simulates yolk sac endoderm. There were only nine survivors among 65 patients on whom follow-up information was available; the actuarial survival was 13% at 3 years. Of the neoplasms that recurred, 93% did so within 1 year, and of those patients who died, 93% did so within 2 years. The size and stage of the tumor had prognostic significance, but the patient's age, the mitotic activity, and histologic pattern did not. Although 71% of the patients had Stage I tumors at the time of diagnosis, subclinical metastasis was present in 84% of Stage I patients. Triple chemotherapy (vincristine, actinomycin D, and cyclophosphamide (VAC)) employed after unilateral salpingo-oophorectomy in four patients with Stage I tumors resultivors among 12 Stage I patients treated with combined surgery and radiation. The finding of AFP in all tumors in which this was evaluated suggests that serum radioimmunoassay might be useful to monitor response to therapy.
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63,319
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Embryonal carcinoma of the ovary: a clinicopathologic entity distinct from endodermal sinus tumor resembling embryonal carcinoma of the adult testis.
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The clinical and pathologic features of 15 examples of a hitherto undescribed germ cell tumor of the ovary are delineated. This tumor resembles the embryonal carcinoma of the adult testis and may be distinguished from the endodermal sinus tumor on the basis of its histologic and immunohistochemical characteristics. An indirect immunoperoxidase method for the localization of human chorionic gonadotropin (HCG) and alpha-fetoprotein (AFP) was done on formalin-fixed paraffin-embedded tissue from 10 neoplasms; HCG was present in all 10 neoplasms, and AFP was found in seven. HCG was indentified only in cells resembling syncytiotrophoblast, whereas AFP was present only in mononuclear embryonal cells, indicating that the two protein antigens were localized in different cell types. Abnormal hormonal manifestations, consisting of precocious puberty, irregular bleeding, amenorrhea, or hirsutism, were present in nine (60%) of the patients. The actuarial survival for the entire group was 39%; for those with stage I tumors, 50%. We are proposing the term "embryonal carcinoma" for this neoplasm in order to distinuish it from the more common endodermal sinus tumor of the ovary and to emphasize the histologic similarity to embryonal carcinoma of the adult testis.
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63,321
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Radioimmunoassay of neocarzinostatin, an antitumor protein.
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Antibodies directed toward the antitumor protein neocarzinostatin (NCS) have been produced in a rabbit by immunization with a highly purified NCS preparation. The antiserum was monospecific and reversed the antibacterial activity of NCS against Sarcina lutea. It cross-reacted with chemically modified derivatives of NCS and mitomalcin but failed to cross-react with macromomycin. A radioimmunoassay procedure has been developed utilizing the antiserum and a biologically active 125I-labeled derivative of NCS. The lower limit of detection by this radioimmunoassay, which involves a double antibody technique for the separation of antibody-bound and free antigen, was 1 X 10(-13) mole. The sensitivity of the assay is such that serum levels of NCS can be determined accurately after administration of the drug to rats at a single dose of 2 mg/kg. Since NCS is now undergoing clinical trial, the radioimmunoassay of the drug will be a valuable tool in clinical pharmacological studies.
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63,320
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Hepatic dearterialization for nonrespectable primary and secondary tumors of the liver.
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Seventeen patients with primary or secondary liver tumors were treated by dearterialization of the liver and intraportal infusion of cytotoxic drugs. In 14 cases, ligation of the main (10), right and left (1), right and middle (1), and right (2) hepatic arteries was performed. In three in whom hepatic artery ligation was considered to be contraindicated due to occlusion of the portal vein, temporary occlusion of the hepatic artery was repeated postoperatively. Only one patient died from the cause related to the ligation. Out of 14 patients who survived for more than one month ten showed an apparent regression of tumors radiologically. The mean survival period of the patients excluding those who died from other unrelated causes was 28 weeks. That of the control patients who received only chemotherapy through the hepatic artery was 13 weeks. The results were not always satisfactory, but dearterialization of the liver can be a palliative treatment for nonresectable liver tumors with a forceful combined chemotherapy.
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63,322
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alpha-Fetoprotein in toxic liver injury.
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The temporal sequence of alpha-fetoprotein appearance in serum was determined in both necrogenic and nonnecrogenic liver injury. Ethionine, thioacetamide, and CCl4 were used to intoxicate male and female rats for evaluating serum enzyme levels, mitotic indices, and morphological reflections of impairment. Thioacetamide- and CCl4-induced cell death preceded the mitotic wave in residual hepatocytes, and, in the case of both agents, this intoxicant-mediated necrosis preceded the emergence of alpha-fetoprotein. Yet, although there was no evidence of either cell destruction or significant mitotic activity in ethionine-poisoned animals, serum alpha-fetoprotein levels progressively increased. Thus the temporal sequence of alpha-fetoprotein synthesis and/or release and cellular reorganization for regeneration suggests that reappearance of the protein macro-molecule is an expression of the altered phenotype observed during the "step-down" phase of liver regeneration.
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63,323
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Genetic control of interindividual variations in the inducibility of aryl hydrocarbon hydroxylase in cultured human lymphocytes.
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Interindividual and intraindividual variations in aryl hydrocarbon hydroxylase (AHH) induction by 3-methylcholanthrene were studied in cultured lymphocytes from normal adult volunteers. Using eight pairs of monozygotic and eight pairs of dizygotic twins, we examined to what extent these variations are controlled by heritable factors and whether AHH inducibility correlations in an individual with the plasma half-lives of three drugs. Substantial overestimation of the induction ratio (fold inducibility) may occur if the nonlinearity of the assay standard curve is not considered. Fold inducibility remains relatively constant for an individual, but large intraindividual variations occur in absolute "control" and "induced" AHH activities. Fetal calf serum may contain inducers of AHH activity that vary with the particular lot of serum, thereby rendering the apparent induction ratio an imprecise indicator of genetic susceptibility to induction by 3-methylcholanthrene. The index of heritability for AHH fold inducibility in twins studied with different lots of fetal calf serum (0.80) or with a single lot of fetal calf serum (0.77) suggests nonetheless that genetic rather than environmental factors are mainly responsible for interindividual variations in AHH inducibility by 3-methylcholanthrene in human lymphocytes. In these twins a significant but poor correlation (r=-0.551; 0.03 less than p less than 0.05) occurs between AHH inducibility in culture and the plasma antipyring half-life, but not between AHH inducibility and phenylbutazone or bishdroxycoumarin half-lives.
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63,324
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Absence of thymus-derived lymphocyte markers in myelogenous leukemia (Ph1+) cell line K-562.
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The myelogenous leukemia cell line K-562 with a Ph1+chromosome, derived from a patient with chronic myelogenous leukemia in terminal blastic crisis, is not a bone marrow-derived lymphoblastic cell line, because the cells neither produce immunoglobulins nor possess complement receptors. Since it has been suspected that blasts found in some patients with chronic myelogenous leukemia in blastic crisis might be thymus-derived cells, we have studied several parameters to demonstrate that K-562 cells are not thymus-derived lymphoblasts. The results of this study show: (a) no cross-reactivity of antisera to K-562 cells with normal human thymocytes; (b) lack of cytotoxicity of a specific horse anti-human thymocyte globulin for K-562 cells; (c) failure of the treatment of K-562 cells with bovine thymosin to induce antigenic determinant and erythrocyte rosette receptors on K-562 cells; (d) presence of receptors for the Fc portion of immunoglobulin G; (e) absence of terminal deoxynucleotidyl transferase; and (f) cytotoxicity of monkey antiserum to K-562 cells for malignant thymus-derived cells (Molt-4). However, absorption with Molt-4 cells abolished the cross-reactivity with Molt-4 cells, whereas 60% of the antibody to K-562 cells remained in the immune serum. Studies of DNA polymerase activities revealed that K-562 cells have levels of polymerase alpha and beta, like other proliferating cells, and an RNA-dependent DNA polymerase activity, presumably representing polymerase gamma.
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63,325
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Evidence for a particle-associated RNA-directed DNA polymerase in rabbit placental and uterine tissues.
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A RNA-directed DNA polymerase associated with particles that band at a density characteristic of type C RNA viruses was found in normal rabbit placental and uterine tissues taken during the early stages of gestation. That the rabbit RNA-directed DNA polymerase is distinct from the known cellular DNA polymerases and similar to the RNA-directed DNA polymerase of mammalian type C RNA viruses is shown by column chromatographic characteristics, template primer preferences, molecular weight determination, and an absolute requirement for the divalent cations.
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63,327
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Two-stage control of cell proliferation induced in rat liver by alpha-hexachlorocyclohexane.
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Determinants of the timing of DNA synthesis in rat liver were studied, using alpha-hexachlorocyclohexane as a tool for stimulation of cell proliferation. One determinant is the time of alpha-hexachlorocyclohexane administration. The increase in DNA synthesis starts after a lag phase (prereplicative phase) of minimally 20 hr. Use of animals adapted to a controlled feeding and lighting schedule revealed a second determinant provided by food consumption. Initiation of DNA synthesis is suppressed by fasting or protein deprivation and occurs 5 to 8 hr after readministration of a protein-containing diet. The light-dark rhythm has no direct influence on the timing of DNA synthesis. Stimulation of hepatic DNA synthesis, therefore appears to require two different sequential signals. The first is provided by alpha-hexachlorocyclohexane, and the second is provided by protein intake. In the absence of the second signal, committed cells are arrested at a critical point of the prereplicative phase and accumulate. Protein intake permits release from the block, and the accumulated cells enter the S period almost synchronously after completion of the remaining 5 to 8 hr of the prereplicative phase. These observations provide a means of synchronizing, in the living animal, a proliferating population of hepatocytes. In addition, they offer an explanation for the diurnal rhythmicity in the rate of hepatic cell proliferation.
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63,326
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Presence of a high-molecular-weight RNA and RNA-directed DNA polymerase in rabbit hereditary lymphosarcoma.
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Rabbit lymphosarcoma tissues contain 70 S RNA and RNA-directed DNA polymerase encapsulated in particulate components that band in the density region of type C RNA viruses. RNA-directed DNA polymerase associated with the particles could be distinguished from cellular DNA polymerases by salt elution from phosphocellulose. The enzyme preferred the template primers poly(rA)-(dT)12-18 and poly(rC)-(dG)12-18 over other synthetic template primers and also utilized viral 70 S RNA as template; these properties are not observed with the known cellular DNA polymerases.
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63,328
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Reduction of N-nitrosodiethylamine carcinogenesis in rats by lipotrope or amino acid supplementation of a marginally deficient diet.
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In studies in this and other laboratories, induction of hepatocardinoma by several different chemical carcinogens was enhanced in rats fed diets deficient in lipotropes (choline, methionine, folic acid), amino acids, and niacin, and high in fat. In some cases, specific supplementation with lipotropes blocked carcinogenesis. In studies reported here, specific supplementation of a marginally deficient diet that enhanced carcinogenesis in rats, with the amino acids or lipotropes in which it was deficient, significantly decreased induction of hepatocarcinoma by N-nitrosodiethylamine. Niacin supplementation decreased hepatocarcinoma incidence only slight; the addition of beef fat to an adequate diet did not enhance tumor induction. Rats fed the amino acid- or lipotrope-supplemented diets had an increased incidence of hepatic hemangioendothelial sarcomas, compared to deficient rats or to rats fed the adequate control diet. Methionine was contained in both the amino acid and the lipotrope supplement and probably was responsible for reducing hepatocarcinoma incidence. Methionine has been found to have an anticarcinogenic effect in other studies and also to block the depletion of hepatic folate stores that is induced by N-nitrosodiethylamine. Interactions between carcinogens, S-adenosylmethionine, and folate may be significant in hepatic or other tissue carcinogenesis. One of more hepatic microsomal oxidases were depressed in rats fed any of the high-fat diets but were not correlated with tumor incidence.
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63,329
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Common tumor rejection antigens in methylcholanthrene-induced squamous cell carcinomas of mice detected by tumor protection and a radioisotopic footpad assay.
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Seven transplantable lines of squamous cell carcinoma of the skin initiated in BALB/c mice by skin painting with methycholanthrene were systematically tested for cross-reactivity of their tumor rejection antigens in a 7 X 7 matrix. As determined by decreased tumor frequency after tumor cell challenge, each line was immunogenic against and/or immunosensitive to at least one and usually more than one of the other lines. A radioisotopic footpad assay for delayed hypersensitivity against viable tumor cells confirmed the cross-reactivity shown by tumor rejection. More than two antigens appeared to be present in the lines. Tests for C-type viruses were positive in all tumors; those for polyoma virus were negative. Whether the uniform presence of C-type viruses can account for the number and variety of antigens found, or whether the tumor rejection antigens are independent of virus expression, remains an open question. The finding of cross-reacting tumor rejection antigens in methylcholanthrene-induced squamous cell carcinomas encourages prospects for the development of more broadly applicable immunodiagnostic and immunotherapeutic reagents.
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63,332
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Phase I clinical trial of combined therapy with vinblastine (NSC-49842), bleomycin (NSC-125066), and cisdichlorodiammineplatinum(II)( NSC-119875).
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Seventeen patients with various histologic types of incurable malignant disease were treated with a combination of vinblastine, bleomycin, and cis-dichlorodiammineplatinum(II). Creatinine and blood urea nitrogen elevations were noted but were not of a severe degree. White blood cell and platelet count depressions were seen and appeared to be cumulative, though not life-threatening. Tinnitus and high-frequency hearing loss were noted. Tumor regression was seen in one patient with adenocarcinoma of the lung and in one patient with a testicular tumor. This appears to be a manageable drug combination with frequent monitoring of renal, hematopoietic, pulmonary, and auditory function. A phase II study establishing the therapeutic efficacy of this combination in advanced testicular neoplasms now appears to be indicated.
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63,331
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Bleomycin (NSC-125066) followed by cyclophosphamide (NSC-26271), vincristine (NSC-67574), methotrexate (NSC-740), and 5-fllorouracil (NSC-19893) for non-oat cell bronchogenic carcinoma.
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The in vivo observation that bleomycin may be used as a synchronizing agent provides the basis for testing 4 days of continuous bleomycin infusion followed by 5 days of intensive chemotherapy with cyclophosphamide, vincristine, methotrexate, and 5-fluorouracil. Thirty-eight patients with extensive non-oat cell bronchogenic carcinoma (adenocarcinoma[17 patients], squamous cell carcinoma[14 patients], and poorly differentiated carcinoma [seven patients]) were registered for chemotherapy. There were 11 patients with 50% regression of all measurable lesions and four with improved but poorly measurable radiographic lesions, providing a crude response rate of 39% (15 of 38 patients). An overall survival median of 19 weeks compares favorably with Veterans' Administration Lung Cancer Study Group control data, but was not substantially better than our own historical controls (P = 0.15). The median survival for responders was 36 weeks compared to 16 weeks for historical controls (P = 0.001) and 12 weeks for nonresponders (P less than 0.001).
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63,334
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Perivascular regions of the rat neural lobe.
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Neural lobes and portions of occipital cortex from rats were examined electron microscopically following fixation in 4% tannic acid in 2.5% glutaraldehyde. The procedure allowed a clear demonstration of the perivascular space and intercellular spaces in both tissues. The perivascular spaces in the neurosecretory tissue was far more extensive than in the neural tissue and the role of this region in relation to the process of neurosecretion is discussed.
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63,335
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Anatomy of the ocellar interneurons of acridid grasshoppers. I. The large interneurons.
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The anatomy of the large ocellar interneurons in the brain of five species of acridid grasshoppers of two different subfamilies (Schistocerca vaga, S. gregaria, Gastrimargus africanus, Trimerotropis pallidipennis, and Arphia conspersa) was revealed by cobalt-filling of the three ocellar nerves and subsequent reconstructions from silver-intensified (Timm's method) serial sections. Conflicts in the literature are reviewed (Tables 1, 2) and differences in the number of cells, anatomical descriptions of these cells, and nomenclature are resolved by demonstration of an identical number of large ocellar identical number of large ocellar interneurons in all five species examined (Fig. 1). There are 17 large 1st-order ocellar interneurons (Figs. 2, 3). Each of the three ocellar nerves contains the axons of seven large interneurons; four of these interneurons have axons in two ocellar nerves. The anatomy of three pairs of 2nd-order ocellar interneurons (with branches in the ocellar tracts within the brain and axons in the circum-esophageal connectives) is reconsidered in light of recent conflicts in the literature. Previous accounts by Williams (1975) of interneurons O2, O3, and PI(2):5 are corroborated and new details added (Fig. 7) by the use of a cobalt method that appears to stain these 2nd-order interneurons transsynaptically (Fig. 6).
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63,336
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Anatomy of the ocellar interneurons of acridid grasshoppers. II. The small interneurons.
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The anatomy of the small ocellar interneurons in the brain of the acridid grasshopper Schistocerca vaga was revealed by cobalt-filling the three ocellar nerves and subsequent reconstructions from silver-intensified (Timm's method) serial sections. In total, 61 small ocellar interneurons were repeatedly identified with arborizations in many areas of the brain and optic lobe, including in particular the posterior neuropil, ocellar tracts, protocerebral bridge, lobula, ventral bridge and tritocerebral crotch, calyces, and antenno-glomerular tracts. Each ocellar nerve contains the axons of small cells that arborize in the other two ocellar tracts; these tracts are sites of ocellar integration. Direct interactions between the ocelli and compound eyes are suggested by the projections of small ocellar interneurons into the proximal lobula. Small cell arborizations from all three ocelli are distributed actoss much of the protocerebral bridge, implying a role for the bridge as an ocellar neuropil within the brain. Four of the small interneurons could be seen in whole-mount preparations and are demonstrated to be identical in five species of acridid grasshoppers of two different subfamilies: Schistocera vaga, S. gregaria, Gastrimargus africanus, Trimerotropis pallidipennis, and Arphia conspersa.
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63,338
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Separation of primary and secondary cardiovascular events in systemic anaphylaxis.
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The purpose of this investigation was to differentiate primary cardiac participation in systemic anaphylaxis from a cardiac reaction secondary to respiratory distress. Hemocyaninsensitized guinea pigs were anesthetized with sodium pentobarbital and artifically ventilated. The chest was opened and the left ventricle cannulated. The electrocardiogram, bronchial resistance, arterial blood pressure, and left ventricular pressure and its first derivative were recorded. Following intravenous administration of antigen, the sinus rate increased by about 50-60 beats/min, left ventricular dP/dt increased by a factor of 3, and mean arterial pressure doubled. Conduction disturbances occurred in all of the experiments and ventricular fibrillation in four of six. These changes were concomitant with a 4-fold rise in bronchial resistance. To separate the cardiac and respiratory components, antigen was administered directly into the left ventricle to expose the heart to antigen before the lungs. The intracardiac challenge resulted in increases in sinus rate and left ventricular and arterial pressure quantitatively similar to changes recorded from guinea pigs after the intravenous challenge. However, all these changes preceded the rise in bronchial resistance by 60 seconds. Arrhythmias occurred as frequently as with the intravenous challenge. Our findings show that by use of an appropriate route for administration of antigen, cardiovascular and respiratory components of systemic anaphylaxis can be separated. Our data also indicate that anaphylactic cardiovascular changes can be dissociated temporally into two sets of events: an initial primary cardiac reaction caused by intracardiac release of histamine and a subsequent cardiovascular reaction secondary to systemic release of mediator.
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63,339
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alpha1-Antichymotrypsin interaction with cationic proteins from granulocytes.
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Human granulocytes contain cationic proteins with chymotrypsin-like activity. These proteases showed a higher relative affinity for alpha1-antichymotrypsin than for alpha1-antitrypsin but the highest affinity for alpha2-macroglobulin. The complexes between cationic protein and alpha1-antichymotrypsin migrate as beta-globulin on agarose gel electrophoresis.
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63,340
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Intracellular localisation of 5alpha-dihydrotestosterone in human benign prostatic hypertrophy.
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When slices of benign hypertrophied human prostate and abdominal muscle were incubated with either [3H]testosterone or 5alpha-dihydro[3H]testosterone, the uptake of radioactivity by prostatic tissue was significantly higher than that of the muscle (P less than 0.01). The uptake of labelled androgen by prostatic tissue could be significantly reduced by adding the unlabelled steroid to the incubation medium. After the incubation of prostatic tissue with 5alpha-dihydro[3H]testosterone, the amount of the radioactivity taken up by the whole homogenate and the nuclear preparation of the prostatic tissue were measured. DNA content of the nuclei and the whole homogenate was also estimated. The mean+/-S.E.M. of 5alpha-dihydrotestosterone associated with the nuclei was 65+/-4.4%, ranging from (52.2-79.8%). The activity of acid phosphatase was measured in 30 samples of prostatic tissue. The mean +/- S.E.M. was 20.7+/-1.5 U/g tissue (9.8+/-0.9 U/mg DNA). The correlation between the activity of this enzyme and the uptake of androgen by prostatic tissue is evaluated.
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63,342
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Influence of hyposensitization of ATP level and CO2 production of mast cells in anaphylaxis.
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Anaphylaxis in a glucose-free medium containing pyruvate caused a release of histamine and a significant decrease in the ATP level of rat mast cells. The fall was maximal after 10 min and it was found to reverse after 22 min. Glucose completely counteracted the ATP fall without changing the anaphylactic histamine release. Furthermore, the oxidative metabolism of exogenous pyruvate to CO2 was stimulated in the mast cell. A high level of protection of mast cells to antigen challenge was obtained following hyposensitization and only a small amount of the intracellular histamine was released in contrast to non-hyposensitized cells. Hyposensitization counteracted the ATP fall by antigen challenge but the increase in oxidative metabolism remained unchanged. The results indicate that hyposensitization exerts effects in the mast cell consistent with a reduced ATP utilization or with a reduced uncoupling of oxidative phosphorylation. The mechanism of the hyposensitization must be due to inhibition of one or more of the cellular steps leading to histamine release and subsequent morphological changes of the cell or to uncoupling of oxidative phosphorylation.
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63,343
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The effects of BCG on both cellular and humoral immunity during the early response to a hapten carrier complex.
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Cell-mediated reactions to the carrier and antibody-mediated reactions to hapten and carrier were studied in guinea-pigs treated with a single i.v. injection of BCG at different intervals of time before immunization with two different doses of a hapten-carrier complex. The results clearly show that BCG-induced delayed hypersensitivity reactions to the carrier and decreased antibody synthesis to the hapten. It is proposed that BCG acts on a dispatcher cell which controls both cellular and humoral immunity.
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63,344
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Purification and characterization of human liver specific F antigen.
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This paper reports the properties of purified human F antigen (liver-specific antigen). Homogenates of liver in 0-25 M sucrose were centrifuged at 105,000 g. The supernatants were chromatographed on Sepharose 6-B and four major peaks were separated. The third peak proved to be predominantly F antigen. This fraction was subsequently subjected to DEAE-cellulose column chromatography and F antigen was eluted at a concentration less than 0-2 M NaCl in 0-01 M sodium phosphate buffer (pH 7-2). Finally, purified F antigen was obtained after preparative isoelectric focusing. Purified human F antigen was found to have a mol. wt between 40,000 and 80,000, a pI of 6-5-6-7 and a density of 1-26. It is a protein antigen and contains no detectable carbohydrate or lipid. No differences were found in purified F-antigen preparations from several species when tested by sodium dodecyl sulphate (SDS) disc gel electrophoresis. Immunofluorescent studies showed that F antigen was homogeneously distributed in the cytoplasm of liver cells but was not present on the cell surface. Immunization of guinea-pigs with purified human liver-specific protein did not induce antibody to the F antigenic determinant defined by mouse anti-F antiserum. It did, however, induce antibodies to two human liver antigens. One of these seems to be a human-specific determinant on the F antigen molecule and the other appears to be a separate molecule which is similar in molecular weight and electrophoretic mobility to the F-antigen molecule.
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63,346
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Cytophilic antibodies in bronchopulmonary aspergilloma and cryptogenic pulmonary eosinophilia.
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The immunoglobulin class and subclass of cytophilic antibodies have been studied using peripheral leucocytes from twenty-two patients with allergic bronchopulmonary aspergillosis, aspergilloma and cryptogenic pulmonary eosinophilia. In patients with allergic bronchopulmonary aspergillosis, significantly increased histamine liberation occurred following challenge of their leucocytes with antisera to IgE, IgG2, IgG3 and IgG4 as well as with Aspergillus fumigatus antigen. The results were considerably modified if the patient was receiving corticosteroids at the time of the test. The presence of IgG2-specific antibody to A. fumigatus in the serum of one patient, capable of sensitizing donor leucocytes, was demonstrated in passive sensitization experiments. In two patients with uncomplicated aspergillomas no evidence of cytophilic antibody to any class was found although large amounts of precipitating IgG antibody was present in the serum. Two patients with aspergilloma and systemic symptoms of weight loss and fatigue (which have been interpreted by others as 'hypersensitivity' responses) had increased amounts of cytophilic antibody similar to those with allergic bronchopulmonary aspergillosis. Six patients with cryptogenic pulmonary eosinophilia were also studied. No evidence of specific antibody to A. fumigatus was found but, as a group, significantly increased histamine liberation using antisera to IgG2 was demonstrated. Individual patients also showed evidence of other classes of cytophilic antibody, one having IgE, three IgG3 and two IgG4. The relationship between heat-stable short-term sensitizing antibody (IgG STS) inducing immediate skin responses and the pattern of cytophilic antibodies found in our patients with bronchopulmonary aspergillosis having dual (immediate and late reactions) is discussed. Clinically these tests are of diagnostic value and they may be helpful in assessing symptomatic patients with aspergillomas for corticosteroid treatment.
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63,345
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Studies on the specificity of smooth-muscle antibodies.
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Purified contractile proteins from smooth and striated muscles have been used to test the specificity of human smooth muscle antibodies (SMA) from patients with chronic liver disease (IgG-SMA) and acute hepatitis (IgM-SMA). The reactions, as detected by indirect immunofluorescence, of IgG-SMA with renal vessel walls, renal glomeruli, peritubular fibrils and the luminal part of the tubular cells could be completely abolished by absorption with either smooth muscle or skeletal muscle F-actin, while absorption with myosin and tropomyosin had no effect. The specificity of IgG-SMA for actin was confirmed by their staining of the actin-rich I-bands of skeletal muscle myofibrils and by the blocking of this reaction by pretreatment of myofibrils and isolated smooth muscle cells with smooth muscle myosin subfragment 1 (S-1). IgM-SMA from patients with acute hepatitis-stained renal vessel walls and some sera also stained renal glomeruli. The IgM-SMA titres decreased after absorption both with myosin and F-actin but not with tropomyosin. The reactivity of some IgM-SMA could be blocked by S-1 while others could not. Thus the specificity of IgM-SMA seemed to be variable, and apparently differed from IgG-SMA in some cases.
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63,350
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The Ia antigens.
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The Ia antigens constitute a polymorphic series of cell surface determinants. At present, their definition is mainly a genetic one, and thus any cell surface antigen which can be demonstrated to be encoded by a gene in the Ir region of the H-2 complex may be classified as an Ia antigen. There are presently three subregions of the I region defined on the basis of available recombinant haplotypes, and designated at I-A, I-B, AND I-C. Mapping of individual Ia specificities indicates that numerous specificities are determined by genes in the I-A subregion, several in the I-C subregion, and few, if any, in the I-B subregion. This may be a reflection of the state of the art, however, rather than an accurate assessment of the extent of polymorphism. The Ia antigens appear to be expressed preferentially on the B-cell subpopulation of lymphoid cells. However, with the use of sensitive techniques they have also been demonstrated on some T cells, on macrophages, on sperm cells, and on epidermal cells. The Ia antigens have also been demonstrated on several T-cell factors which appear to be involved in the immune response. Whether or not all of the Ia antigens thus localized are identical or represent overlapping specificities within the same sera remains in many cases to be determined. There are presently three ways of defining Ia specificities serologically: (1) by direct immunization between strains differing only in the I region; (2) by detection of shared Ia determinants using polyspecific sera which contain H-2K region and H-2D region antibodies but which are nevertheless specific only for Ia antigens when tested on target cells of other strains; and (3) by selective absorption of H-2K region and H-2D region antibodies from an H-2 antiserum by cells bearing these antigens but lacking (or relatively lacking Ia antigens. All three of these methods produce anti-Ia reagents of reasonable titer for use in both serological and functional experimentation. The definition of the specificity as an Ia specificity in each case requires the availability of appropriate recombinant strains to map the specificity to the Iregion. In addition, there are several correlative criteria which have been developed in order to detect Ia activity in alloantisera in the absence of the availability of appropriate recombinants for mapping of the specificity. These include the tissue distribution of the Ia antigens (namely, their predominant expression on the B-cell subpopulation), their characteristics molecular size, their association on the B-cell surface with the Fc receptor, and their lack of association with other products of the major histocompatibility complex as distinguished either chemically or by cocapping studies. These correlative criteria make it possible to distinguish probable anti-Ia reactivity in a variety of serological reactions, but the results must still be interpreted with caution until appropriate recombinants have been obtained which can map the specificities to the I region...
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63,354
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Preliminary amino acid sequences of transplantation antigens: genetic and evolutionary implications.
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Preliminary amino acid sequence data on the transplantation antigens of mouse and man have led to provocative hypotheses about the genetic organization and evolution of genes coded by the major histocompatibility complex of mammals. New microsequencing techniques should permit a detailed analysis of these gene products and an eventual choice among the alternative hypotheses now posed. These data have made it apparent that the H-2 complex is a fascinating and complicated chromosomal region which will continue for some time to intrigue immunologists, geneticists, biochemists, and cell biologists.
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63,355
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Serum protein synthesis in mutant mice with abnormal hepatic endoplasmic reticulum.
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Severe ultrastructural abnormalities of liver endoplasmic reticulum have been described in newborn mice homozygous for radiation-induced deletion alleles at the colour locus. The ultrastructural defects were accompanied by deficiencies of several enzymes and lowered serum protein levels. Studies on serum protein synthesis were undertaken to see if decreased rates of synthesis, especially of constituents thought to be synthesized on membrane-bound ribosomes, were the cause of the deficiencies. Although decreases or absence of several serum proteins were shown, radiopulse-immunoprecipitation studies of albumin and fibrinogen synthesis suggested that the decreased synthesis rates were a secondary defect. Serum glycoproteins were not altered more than other constituents in the mutant material.
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63,356
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Negotiating educational programs for children with developmental disorders: assessment, interpretation, demonstration, support (AIDS).
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An approach to negotiating educational programs for children with multiple developmental problems is presented using two case examples from an interdisciplianry setting, the University Affiliated Cincinnati Center for Developmental Disorders. The use of the AIDS (Assessment, Intervention, Demonstration, Support) approach offers the schools evidence that the professional educator and psychologist are working in good faith and will not abandon them prematurely. Proper school placement through mediation also allows the school personnel to receive credit from the family for making the necessary changes, therefore not losing face with the parents. This approach seems particularly applicable to children with multiple and chronic problems who do not fit single special educational/diagnostic categories or labels.
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63,357
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Detection of sister chromatid exchanges by 4'-6-diamidino-2-phenylindole fluorescence.
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This paper describes a 4'-6-diamidino-2-phenylindole (DAPI) fluorescent technique for differentiation of sister chromatids and for the study of sister chromatid exchanges (SCE) in mouse chromosomes. The advantages of the DAPI fluorescent technique are also described. Differences in the occurrence of SCE between the centromeric heterochromatin (C-banded) and the chromosomal arm chromatin were studied in mouse cells (RAG) with or without mitomycin C treatment. Single strand exchanges between the DNA double helices in the sister chromatids were not detected. SCE and chromosome breakage appeared to occur more frequently in the centromeric region than in the chromosomal arm. This might play an important role in chromosome evolution in mice.
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63,358
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Characterization of Drosophila heterochromatin. I. Staining and decondensation with Hoechst 33258 and quinacrine.
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A number of preliminary experiments have shown that the fluorescence pattern of Hoechst 33258, as opposed to that of quinacrine, varies with the concentration of dye. The metaphase chromosomes of D. melanogaster, D. simulans, D. virilis, D. texana, D. hydei and D. ezoana have therefore been stained with two concentrations of H 33258 (0.05 and 0.5 mug/ml in phosphate buffer at pH 7) and with a single concentration of quinacrine (0.5% in absolute alcohol). The three fluorescence patterns so obtained were shown to be somewhat different in some of the species and the coincide in others. All three stainings gave an excellent longitudinal differentiation of heterochromatin while euchromatin fluoresced homogeneously. Living ganglion cells of the six species mentioned above were treated with quinacrine and H 33258. Quinacrine induced a generalized lengthening and swelling of the chromosomes and H 33258 the decondensation of specific heterochromatic regions. A correlation of the base composition of the satellite DNAs contained in the heterochromatin of the species studied with the relative fluorescence and decondensation patterns showed that: 1) the extremely fluorochrome bright areas and those decondensed are present only in species containing AT rich satellite DNA; 2) the opposite is not true since some AT-rich satellite DNAs are neither fluorochrome bright nor decondensed; 3) there is no good correspondence between Hoechst bright areas and the decondensed ones. AT richness therefore appears to be a necessary but not sufficient condition both for bright fluorescence and decondensation. Some cytological evidence suggests that similarly AT rich satellite DNAs respond differently in fluorescence and decondensation because they are bound to different chromosomal proteins. A combination of the results of fluorescence and decondensation revealed at least 14 types of heterochromatin; 4-7 of which are simultaneously present in the same species. Since closely related species (i.e. D. melanogaster and D. simulans; D. virilis and D. texana) show marked differences in the heterochromatic types they contain, it can be suggested that within the genus Drosophila qualitative variations of heterochromatin have played an important role in speciation.
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63,360
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Sequence of DNA replication in 277 R- and Q-bands of human chromosomes using a BrdU treatment.
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Replication times for all important chromosome bands, of both types R and Q (277 structures) are analysed. The R-bands form a group of structures whose DNA replicates during the early S-phase, while the DNA situated in the Q-bands replicates during the late S-phase. There may not exist overlapping between replication times of these two types of structures. The widest R-bands are those which are the earliest to replicate; in general, the most intense Q-bands are those which are the latest to replicate. Especially among these last ones, a certain asynchronism exists between the replication times. Finally the heterochromatin of chromosomes 1, 16 and Y and of the short arms of the acrocentrics could contain two types of DNA which replicate at different times.
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63,359
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Characterization of Drosophila heterochromatin. II. C- and N-banding.
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The C- and N-banding patterns of D. melanogaster, D. simulans, D. virilis, D. texana, D. ezoana and D. hydei were studied in comparison with quinacrine and Hoechst banding patterns. In all these Drosophila species the C bands correspond to the heterochromatin as revealed by the positive heteropycnosis in the prometaphase chromosomes. The N bands have the following characteristics: 1) they are always localized on the heterochromatin and generally do not correspond to the C bands; 2) they do not correspond to the nucleolar organizing regions; 3) they are inversely correlated with fluorescence, i.e., they correspond to regions which are scarcely, if at all, fluorescent after Hoechst 33258 or quinacrine staining; 4) they are localized both on regions containing AT rich satellite DNA and on those containing GC rich satellite DNA.
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63,361
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Characterization of the toromeric structure in Drosophila lummei.
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The toromere, a structure previously reported only in several strains of Drosophila melanogaster, is found in salivary gland nuclei of three populations of Drosophila lummei, a member of the virilis group. The toromere is characterized by being quinacrine-bright and Feulgen-positive. Further staining and enzyme digestion procedures reveal that the toromere is composed of double-stranded DNA with little or no protein complexed with it. The toromere appears as a small quinacrine-bright dot in diploid cells and apparently undergoes polytenization, as it is observed as a large quinacrine-bright doughnut-shaped structure in salivary gland preparations. We describe the effect of larval culture temperature on the morphology and number of toromeres per cell, and lend support to the proposal that the toromere could be a highly replicated episome.
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63,363
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In vivo BrdU-33258 Hoechst analysis of DNA replication kinetics and sister chromatid exchange formation in mouse somatic and meiotic cells.
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BrdU (5-bromodeoxyuridine)-33258 Hoechst methods have been adapted for in vivo analyses of replication kinetics, sister chromatid differentiation and sister chromatid exchange (SCE) formation in mice. Sufficient in vivo BrdU substitution for cytological detection was effected with multiple intraperitoneal injections of the analogue. The combination of centromere staining asymmetry and sister chromatid differentiation at metaphase permits unambiguous determination of the number of replications in BrdU and dT (deoxythymidine) undergone by individual cells. Late-replicating regions in marrow and spermatogonial chromosomes are highlighted by bright fluorescence after sequential incorporation of BrdU followed by dT during a single DNA synthesis period. SCEs are analyzed in marrow and spermatogonial metaphases after successive complete cycles of BrdU and dT incorporation. Significant induction of SCE was observed with both mitomycin C and cyclophosphamide; the latter drug requires host-mediated activation to be effective. In meiotic metaphase cells harvested two weeks after BrdU incorporation, satellite DNA asymmetry, sister chromatid differentiation and SCE could be detected in a few chromosomes, most frequently the X and the Y.
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63,362
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Dotted chromosomes produced in sodium phosphate solution supersaturated with NaHCO3.
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Dotted chromosomes were consistently produced in both BrdU and non-BrdU substituted Chinese hamster cells after treatment with 1.0 M Na-phosphate solution, adjusted to pH 9.0 with a supersaturating amount of NaHCO3, and at a temperature of 80--95 degrees C. -- A series of changes in chromosome morphology was produced as the temperature of the solution was progressively increased. In BrdU-treated cells, G-banding and differentially stained sister chromatids were sequentially produced prior to the appearance of dots. In non-BrdU treated cells, only G-banding was produced before dot formation. In general, the patterns of dots correspond to the G-banding patterns. --Chromatids, with uni- or bifilarly BrdU substituted DNA or with normal DNA, required differential temperatures for the production of dots. Since the temperature required for dot formation was always slightly higher than that required for producing differentially stained chromatids, this phenomenon can be used as an important indicator for determining the optimal temperature required for revealing differentially stained chromatids.
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63,364
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Xerophthalmia and measles in Kenya.
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In many African countries measles is considered to be an important cause of blindness. On the basis of his observations in Kenya and Tanzania in 1972 Franken presumed, however, that in the majority of these cases xerophthalmia was the real cause of blindness, precipitated by the "catalyst" measles. In order to gain a better understanding of this important complicated problem, we performed in the first half of 1974 an investigation in Kenya into the prevalence of xerophthalmia. In December 1974 we had the opportunity to evaluate our Kenyan findings on Java, in the company of Dr. J. ten Doesschate and Professor H.A.P.C. Oomen. The results of this investigation in Kenya and Indonesia are presented in this thesis. (see article) 1. Xerophthalmia occurred nearly everywhere in Kenya in 1974. This demonstrates the prevalence of xerophthalmia in communities which - do not have rice but - have maize for their staplefood. 2. Xerophthalmia appears to be the main cause of blindness in Kenyan children. 3. Measles often plays - by means of local and general "catalysing" effects - an important role in the development of blindness caused by xerophthalmia. 4. In well-nourished children measles is of no consequence as a cause of blindness. 5. Vital staining by 1% rose bengal or 1% lissamine green appears to be a real asset for the early diagnosis of xerophthalmia in Health Centres and in field surveys. This method is therefore of great importance for the prevention of severe, blindness inducing vitamin A deficiency.
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63,367
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[Principles of programmed teaching].
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Student education and continued education programs increase the stress on a dental school teacher as far as time is concerned. The use of modern aids gives an effective relief, if existing teaching materials in basic fields can be taken over. Quality characteristics and basics of the evalutation of teaching programs are presented.
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