pmid
int64 21
9.18M
| title
stringlengths 4
512
| abstract
stringlengths 2
9.99k
|
|---|---|---|
63,368
|
Nature of cross-reaction between hCG and anti-oLH serum and development of a radioimmunoassay to measure hLH specifically in the presence of hCG.
|
Immunological cross-reaction between hCG and anti-oLH sera has been demonstrated using radioimmunoassay techniques. The results indicate that this cross-reaction is incomplete and that the anti-oLH sera used have the ability to distinguish between LH and hCG. Following absorption with purified hCG, anti-oLH serum was used to develop a heterologous radioimmunoassay "[125I]iodo-hLH + anti-oLH serum" (H-O, RIA) which specifically and selectively measures hLH in serum samples containing both hLH and hCG. In this radioimmunoassay hCG and subunits of hCG do not cross-react with hLH, in the range in which these hormones are present in human serum under physiological conditions. Other hormones such as hPL, hPRL, hGH, hFSH, hTSH, and GnRH do not interfere with the measurement of LH by radioimmunoassay. The sensitivity of the assay was 1.5 mIU (25 ng) per ml (LER 907 standard), and the inter- and intra-assay coefficients of variations for samples were 10.83% and 8.4%, respectively. The recoveries of hLH added to pregnancy serum containing an hCG concentration of 8.55 IU/ml were in the range 95-108%. Determination of LH content of human pituitary extracts by H-O RIA gave values which were in close agreement with those derived by bioassay (indices of discrimination 0.72-1.12). Serum LH patterns in women during normal menstrual cycles as well as in amenorrheic patients who received GnRH treatment are comparable to those reported by other investigators using other radioimmunoassay systems. Serum samples obtained during the first trimester of pregnancy, when analyzed by H-O RIA, showed basal LH levels.
|
63,370
|
Quinidine syncope: torsade de pointes with low quinidine plasma concentrations.
|
In 2 patients without clinically significant ischemic heart diseases, oral quinidine was used to control supraventricular arrhythmias. In both patients, syncopal attacks occurred, caused by a particular type of ventricular tachyarrhythmia called torsades de pointes. Quinidine plasma concentrations were low (2.6 and 1.2 mg/1, respectively); QRS duration was normal, but the Q-T interval was markedly prolonged.
|
63,371
|
Increased plasma binding of quinidine after surgery: a preliminary report.
|
The plasma binding of quinidine and phenytoin has been studied pre- and postoperatively in nine patients submitted to planned gastric surgery. The binding of phenytoin showed a slight and transient reduction, whilst quinidine binding was markedly increased, on average from 78.5% on the day of operation to a maximum of 87.5%, after 2-4 days. The time course of the increase was strikingly parallel to that of the concentration of certain acute phase proteins.
|
63,372
|
Blockade of specific antibody-forming cells in vivo by dextrans and levans.
|
Fractions of dextrian (DE) B512, DE B1355 and levan (LE) have been shown to induce a specific blockade of antibody-forming cells (AFC) when injected into previously immunized mice. Whereas specific blockade with DE B512 (450 000 daltons) was easily induced by as little as 10 mug, blockade to LE and DE B1355 was more resistant and required 1 and 10 mg, respectively. AFC blockade and tolerance are dissociable phenomena, as the former effect could be achieved with nontolerogenic low mol. wt DE B512 (10 000 daltons). Conversely, perennial rye grass fructosan (7600 daltons), which is tolerogenic for LE, did not induce a blockade. Furthermore, blockade of anti-DE response specific for alpha (1 leads to 3)-linked glucosyl determinants was achieved in BALB/c mice, whereas attempts to induce stable tolerance have been unsuccessful.
|
63,373
|
HLA-B specificities and w4, w6 specificities are on the same polypeptide.
|
The human alloantigenic specificities w4 and w6, which are products of a diallelic system genetically associated with the HLA-B locus, have been solubilized by papain digestion of membranes from the lymphoblastoid cell line, RPMI 4265. The w4 and w6 specificities copurified with the HLA-B locus products, HLA-B7 and HLA-B12. Sequential immunoprecipitation experiments were performed using alloantisera to HLA-B7, HLA-B12, w4 and w6, and a purified HLA-B7, B12, w4, w6 antigen pool labeled with 125I-Bolton-Hunter reagent. These experiments demonstrated directly that HLA-B7 and w6, which are genetically associated with each other, are different antigenic determinants on the same molecule, while HLA-B12 and w4, also genetically associated, are distinct antigenic determinants on a second molecule. Arguments are presented which suggest that the HLA-B determinants and w4, w6 determinants are in fact on the same polypeptide, and the genetic implications of the findings are discussed.
|
63,374
|
Antigen, host and adjuvant requirements for induction of hyperacute experimental autoimmune encephalomyelitis.
|
A hyperacute form of experimental autoimmune encephalomyelitis (HEAE) was induced in Lewis rats using small doses (3.2 mug) of guinea pig myelin basic protein as immunogen and B. pertussis vaccine as adjuvant. Myelin basic proteins from species other than guinea pig (rat, man, monkey, pig, ox, rabbit and sheep) induced only ordinary EAE with this adjuvant. HEAE was more readily distinguished from ordinary EAE by clinical criteria (early onset, with a rapid and severe course, and high incidence of cerebral signs and mortality) than by histologic signs which, although characteristic of HEAE. were not pathognomonic for HEAE, HEAE was transferred to x-irradiated syngeneic recipient rats with lymph node cells from appropriately immunized donors. The Brown Norway (BN) strain of rat was found susceptible to induction of ordinary EAE, but not HEAE, using large doses of either rat or guinea pig myelin basic proteins. The unique immunogenicity of the guinea pig basic protein must be due to a different antigenic determinant from the determinant(s) which is shared by rat and guinea pig myelin basic proteins and which without B. pertussis induces ordinary EAE. The adjuvant action of B. pertussis in inducing HEAE in the Lewis rat is most likely mediated through an immunocompetent T lymphocyte.
|
63,375
|
Effect of prior sensitization with hapten on the antibovine IgG antibody response to hapten-conjugated tolerogen of mice tolerized by low doses of bovine IgG.
|
Mice tolerized by low doses of bovine IgG (BGG), immunized with arsanilated (ARS) conjugates and challenged with ARS-BGG show an augmented anti-BGG antibody response compared with controls immunized with nonconjugated carrier. Conditions optimal for generating hapten help are explored and suggest that the phenomenon is mediated by hapten-specific helper T cells. During exploration of these conditions it became apparent that the response was suppression rather than augmentation with ARS, under certain circumstances, and with 2,4-dinitrophenyl, 4-hydroxy-5-iodo-3-nitro-phenylacetyl (NIP) and sulfanilic acid, under all conditions tested. Especially important in determining the outcome of the interaction was the type of adjuvant used for hapten priming. The significance of these observations is discussed in relationship to the balance between negative and positive cooperation.
|
63,376
|
Beta2-microglobulin distribution in human normal tissues.
|
The distribution of beta2-microblobulin in human normal tissues was investigated by the indirect immunofluorescent antibody method. Lymphoid, macrophage and endothelial cells were consistently positive in every organ studied. In addition, only the stratum germinativum of the epidermis, some tracts of the columnar epithelium of the digestive system and some endometrial tubular glands showed a specific fluorescence.
|
63,377
|
Naturally-occurring double-stranded RNA and immune responses. IV. Influence of molecular size on antigenicity and adjuvant activity.
|
The immunological properties of a naturally-occurring double-stranded ribonucleic acid (ds-RNA), obtained from a mycophage of Penicillium chrysogenum, have been studied in relation to molecular size. Materials of reduced size, as reflected by molecular weight measurements, produced by ultrasonication of native ds-RNA, exhibited progressively lowered ability to induce an anti-ds-RNA response in mice. Adjuvant and immunosuppressive activities were of similar magnitude in both high and low molecular weight fractions. Evidence was also obtained of increased toxicity in materials of reduced size.
|
63,378
|
Antigenic determinants of heavy chain variable regions: immumological typing of the human immunoglobulin VHIII subgroup.
|
An antigenic determinant of the VHIII variable region subgroup was defined by means of a heterologous specific antiserum using a hemagglutination inhibition procedure. The specificity of this antiserum was established in inhibition experiments with proteins either of known primary structure or belonging to a definite VH subgroup. A series of IgG, IgA, IgM and IgD monoclonal proteins was examined for the presence of this VHIII subgroup antigenic determinant. The data showed that 50% of the IgG, 62% of the IgA, 55% of the IgM and 41% of the IgD were VHIII-positive, and that certain "blocked" monoclonal immunoglobulins belonged to this subgroup. A preferential association of the VHIII antigenic determinant with the IgG1 and IgG3 subclasses was observed among IgG myeloma proteins while the preferential association was only observed with the IgG1 subclass when anti-Rh antibodies were studied. The VHIII subgroup exhibited nonallelic behavior.
|
63,379
|
Shared determinants between virus-infected and trinitrophenyl-conjugated H-2-identical target cells detected in cell-mediated lympholysis.
|
Infection of H-2-identical mice with either lymphocytic choriomeningitis (LCM) virus, vaccinia virus, or paramyxo (Sendai) virus resulted in the generation of specifically sensitized cytotoxic T lymphocytes (CTL). CTL generated in vitro against 2,4,6-trinitrophenyl (TNP)-conjugated syngeneic stimulator cells were specifically cytotoxic for TNP-conjugated H-2K (D) region identical targets. Both LCM and vaccinia-induced CTL, however, were found to be strongly cytotoxic towards TNP-conjugated, H-2K(D) region-identical target cells. In contrast, Sendai virus-induced CTL did not lyse TNP-conjugated, syngeneic target cells. Inhibition experiments using cold targets suggested that shared antigenic determinants can be detected on either LCM virus-infected and TNP-conjugated targets, which are not present on the cell surface of normal target cells.
|
63,380
|
Role of epitope density in the induction of tolerance and immunity with thymus-independent antigens. III. Interaction of epitope density and receptor avidity.
|
The induction of B cell tolerance to 2,4-dinitrophenyl conjugates of polysaccharide antigens (levan or dextran) was studied in mice primed with keyhole limpet hemocyanin (KLH) or 2,4,6-trinitrophenylated KLH. The relationship of the epitope density of the tolerogen with avidity of B cell receptors (as judged indirectly by a plaque inhibition assay) was investigated. It was found that high avidity precursors (IgG) were tolerized by antigen of much lower epitope density, and at lower concentration, than were low avidity precursors (especially IgM cells). IgA cells were intermediate in behavior. These results suggest that the epitope density effect acts by ensuring a necessary degree and/or energy of antigen binding.
|
63,381
|
Evidence for an absence of cross-reactivity between the human beta2-microblobulin and human IgG allotypes and subclasses.
|
Six beta2-microglobulins were isolated from the urine of six patients with renal tubular dysfunction. Cross-reactivity between these beta2-microglobulins and antigenic determinants of different IgG allotypes and subclasses was investigated. No evidence of cross-reactivity was found. Some hypotheses are discussed concerning these results.
|
63,382
|
Synthesis and release of histamine studied on slices from rat hypothalamus.
|
In slices from rat hypothalamus, incubated in the presence of 3H-L-histidine (3H-L-His), the aminoacid was rapidly taken up by a saturable process, and partially converted into 3H-histamine (3H-HA). The overall conversion was prevented either by inhibitors of L-histidine decarboxylase or by aromatic aminoacids competing with L-His uptake. The synthesis process exhibited Michaelis--Menten kinetics with an affinity of the aminoacid not different from that for the decarboxylase in homogenates; however the Vmax in homogenates was more than 10 times higher than in slices. Depolarization of the slices by 50 mM potassium resulted in: (a) a calcium-dependent release of 3H-HA which was more marked than that previously reported for endogenous HA, (b) a significant acceleration in the rate of 3H-HA synthesis, which was characterized by an unchanged Km but a significantly elevated Vmax. The regulation of HA synthesis did not appear to depend on end-product inhibition since it was not midified by the addition of exogenous HA. The release of 3H-HA was followed by the accumulation of 3H-methylhistamine, which was enhanced by a monoamine oxidase inhibitor. Aminoguanidine, a diamine oxidase inhibitor, had no effect on catabolism. The involvement of mast-cells in the storage of a fraction of endogenous HA in hypothalamic slices was assessed by the significant releasing effect of compound 48/80. Hence, the data support the existence of two distinct HA stores in the brain: depolarization relases the amine and increases its synthesis, probably in neurones, whereas compound 48/80 releases it from a slowly turning-over store, probably in mast-cells.
|
63,383
|
The retinal projection to the ventral part of the lateral geniculate nucleus. An experimental study with silver-impregnation methods and axoplasmic protein tracing.
|
The retinal projection to the ventral part of the lateral geniculate nucleus (LGNv) was studied in 25 adult cats. In 12 cats one or both eyes were enucleated and the terminal degeneration in the LGNv was studied with silver impregnation methods. In 12 cats one or both eyes were injected with 3H-leucine and the terminal labelling in the LGNv was studied with autoradiography. In one animal one eye was enucleated and the other injected. In this case alternate sections were silver impregnated and processed for autoradiography. The series were cut in parasagittal, transverse or horizontal planes. The results revealed by degeneration were in very good agreement with those revealed by axoplasmic protein tracing. Two fields of retinal projection were found in the LGNn. The larger, dorsal one was restricted to subnucleus k (Jordan and Holländer, 1972) and comprised an ipsilateral and a contralateral component which did not overlap each other. The smaller, ventral field of projection was contralateral and extended from subnucleus b into c, e and a. The afferent optic tract fibres to both terminal fields were of small calibers.
|
63,384
|
The climbing fibers of the cerebellar cortex, their origin and pathways in cat.
|
The sources and pathways of the climbing fibers to the cerebellar posterior vermis were studied with comibined electrophysiological and anatomical methods in cats. Recording from identified cerebellar Purkinje cells, monosynaptic climbing fiber (CF) responses have been obtained both for stimulation of the inferior olive (IO) and various parts of the brain stem (BS). CF responses were found to of three types, IO only, BS only or both IO and BS. However the responses to BS stimulation were very few in number in comparison with IO or IO and BS types of responses. The latencies of the responses were shorter for the BS cases consistent with their distance from the cerebellum. A comparison of latencies and the relative responsiveness of the different area of the brain stem which were studied, indicate that part of the CF ascend through the pontine region and enter the cerebellum by way of the medium and superior penduncles. This finding is confirmed by the results of anatomical studies in which degenerating fibers were found in the molecular layer (using the Nauta technique) after lesion of the brachium pontis but not after lesions of the medial portion of the pons. Similarly, injection of radioactive leucine into the pontine nuclei failed to show any labeled fibers in the molecular layer. Horseradish peroxidase (HRP) was injected into localized regions of the posterior vermis after total bilateral destruction of the inferior peduncles. Large numbers of positive, marked cells were still found in the inferior olive. It is concluded that nearly all, if not all, the climbing fibers originate in the inferior olive and that they ascend to the cerebellum by way of all the peduncles.
|
63,405
|
Immunological heterogeneity in human ferritinemia.
|
Hyperferritinemia in various diseases, mainly hematological, was confirmed by immunological methods. For ferritin detection, anti-human placental ferritin antiserum, anti-human hepatic ferritin antiserum, and anti-human leukemia cell ferritin antiserum were used and the result was compared with each other. Leukemia, malignant lymphoma, multiple myeloma, and aplastic anemia are hematological diseases which showed a positive reaction in this test, among which leukemia showed the highest positivity. Cases of hepatic diseases and non-hematological malignant neoplasms also showed a positive reaction. The positivity was quite low and almost negligible in other diseases and healthy individuals. Anti-human placental ferritin antiserum seemed to be suitable for cancer diagnosis and, antihuman hepatic ferritin antiserum for hepatic diseases. The results of analysis of purified human hepatic and placental ferritins highly suggested the presence of immunological heterogeneities between them. Also, a possibility was pointed out that one of the components of the so-called leukemia-specific antigens might sometimes be the isoferritin of leukemia cells.
|
63,406
|
Determination of the bleomycin-inactivating enzyme in biopsies.
|
A method for the determination of the Bleomycin-inactivating enzyme is described. The amount of conversion of active Bleomycin to inactive Bleomycin is used as a measure for the determination of the Bleomycin-inactivating enzyme activity. The active Bleomycin is determined in a DNA-dependent DNA polymerase assay; in a certain Bleomycin concentration range the resulting reduction of the activity of the DNA-dependent DNA polymerase is correlated linearly when plotted semilogarithmically. By application of this method it has been found that the activity of the Bleomycin-inactivating enzyme is highest in liver and present in lower concentrations in testis, spleen, lung, brain, and skin.
|
63,407
|
[Successes and prospects for genetic engineering].
|
The review of literature (1970-1976) on problems of gene engineering is given. Gene engineering is pointed out to be a new method of modern biology and a new page of modern molecular genetics. Gene engineering detected a real possibility of artificial creating living hybrid organisms, i.e. constructing functional recombinant DNA molecules according to a project of investigator, but not to possibilities of crossing. The determination of gene engineering (in contrast with genetical engineering) is given in the first division of the article. Genetical engineering is a construction of hybrid organisms on the basis of recombination between non-homologous chromosomes cy crossing. Genetical engineering is based on sex crossing, thus the application of this method is restricted by crossability (i.e. experiments in vivo), which possibilities are determined by taxonomical limits. Gene engineering is a new method of operating directly with genes. It permits constructing in vitro any hybrid genomes desirable. There is no limits of combining ability for gene engineering. Three main stages of constructing hybrid genomes should be taken into account for the proper determination of gene engineering as a method of genome constructing: 1) the gene isolation; 2) their cross-linking in vitro; 3) the transfer of hybrid DNA into recipient cell or its genome. The cardinal stage of gene engineering is the construction of hybrid DNA, cross-linking any initial DNAs from any remote animals, plants and bacteria. All the methods known of gene isolation are described. The chemical method of gene isolation is based on that case, when DNA of some gene differs in its physico-chemical characteristics from total DNA, for example, DNAs of genes coding ribosomal RNAs or sea urchine histone DNA. Isolation of promotors and operators using DNA dependent RNA polymerase, which recognizes promotors, repressor and operator DNA, should also be considered as the chemical method of gene isolation. Restrictase method, which is also well known, is convenuent because the restricts have long enough sticky ends, which is important for the following gene cross-linking. The method of total restriction, reported by Lederberg et al. and Debabov et al., is described. The phage method (in particular, Shimada method) is given, permitting the direct integration of lambda phage into a number of sites of Escherichia coli chromosome. Gene engineering method of gene isolation is mentioned, in particular, the data of Kameron et al. on hybrid phages carrying DNA ligase gene, and Clark a. Carbon on hybrid plasmids carrying triptophane and arabinose operons genes. These methods are called "shot gun". Methods of gene isolation from higher organisms are less developed. A method of gene isolation using so called colony hybridization (according to Grünstein and Hognes) is also given...
|
63,413
|
Demonstration of an intracellular copper-binding protein by orcein staining in long-standing cholestatic liver diseases.
|
Liver biopsies from eight patients with primary biliary cirrhosis, two with chronic active hepatitis of a cholestatic form, three with long-standing alcoholic liver cirrhosis, and one with extrahepatic biliary obstruction were studied. In each case dark brown cytoplasmic material was seen after staining of the tissue sections with Shikata's orcein method. In exactly the same cellular and subcellular locations as the orcein-positive material, and with morphologically equal granules, two different ordinary staining methods for copper (rubeanic acid and Mallory-Parker's haematoxylin) gave positive reactions. The earlier histochemical findings have revealed the protein nature and high sulphydryl content of the orcein-positive material. Its close association with copper in liver sections suggests its copper-binding nature and indicates that a common copper-protein complex accumulates in the cytoplasm of liver cells during longstanding cholestasis in biliary diseases of various pathogenetic origin.
|
63,414
|
Morphological types of hepatocellular hyalin in Indian childhood cirrhosis: an ultrastructural study.
|
Morphological variants of intrahepatocytic hyalin in Indian childhood cirrhosis have been analysed by electron microscopy. This structure, morphologically identical with Mallory's alcoholic hyalin, is encountered in three different forms. The most common one is composed of randomly oriented fibrils. The next common type is composed of smudgy homogeneous or finely granular material, while the least common type consists of parallel fibrils with gentle curves giving a 'finger-print' appearance. Fragmented endoplasmic reticulum and ribosomes were frequently associated with hyalin suggesting that these organelles contribute to their formation.
|
63,416
|
Correlations between radioiodine uptake and blood viscosity factors in hypothyroid and hyperthyroid states.
|
A study of blood viscosity factors was undertaken in six hypothyroid and eleven thyrotoxic patients (females) whose thyroid function was defined by means of radioiodine uptake and protein bound (PB) 131I tests. Results indicate that: (i) significant differences exist between hypothyroid and hyperthyroid groups in correlations between radioiodine tests and blood viscosity factors (and fibrinogen levels); (ii) blood viscosity in thyrotoxic patients decreases as the degree of thyrotoxicity increases, while an opposite phenomenon is observed in hypothyroid patients, and (iii) degree of rigidity of the red cells is associated with the radioiodine uptake and PB 131I tests, the correlations being significant and negative.
|
63,415
|
Cell-mediated immunity in pregnant women.
|
Phytohemagglutinin-induced lymphocyte transformation (PHA-T) was depressed in pregnant women, as compared with that in nonpregnant women. Pregnancy serum had a suppressive action on PHA-T which was enhanced with the advance in pregnancy. Hydrocortisone, progesterone, alpha-fetoprotein and trophoblast-specific antigen, were demonstrated as immune suppressive factors. From these results, it was concluded that cell-mediated immunity might be reduced in pregnant women and that this reduction might be one of the causes for the maintenance of pregnancy.
|
63,440
|
An improved technique for selective silver staining of nucleolar organizer regions in human chromosomes.
|
A reliable technique for staining human chromosomal nucleolar organizers (NOR's) with silver solutions is described. The NOR's can be selectively stained dark brown by silver solutions leaving the chromosome arms unstained and available for counterstaining with orcein or Giemsa dyes. Unequivocal identification of chromosome pairs bearing NOR's can be achieved using fluorescent banding techniques followed by silver staining. The silver staining procedure for NOR's was simplified and standardized through control of the chemical and physical conditions during silver impregnation and developing.
|
63,442
|
Segmentation of human chromosomes induced by 5-ACR (5-azacytidine).
|
The 5-ACR (5-azacytidine) introduced in human lymphocyte cultures induces a lack or a delay of condensation of some chromosome segments corresponding to the G-bands. The resulting R-banding is very similar to that obtained with a 7-h treatment by BrdU, although the segmentation may be much stronger (pulverization) with high doses. However, the 5-ACR does not induce chromatid asymmetry, as BrdU does. This constitutes a new argument for considering that the segmentation and the asymmetry of chromatids depend, at least partly, on two different mechanisms, where proteins are probably involved. Another effect of 5-ACR is to increase chromosome associations by satellites, secondary constrictions, and telomeric regions.
|
63,443
|
Studies on the altered electrophoretic type of the factor VIII related antigen.
|
A distinct sub-group of von Willebrand's disease is characterized by an electrophoretically faster mobility of the factor VIII related antigen. Some of the physico-chemical properties of this variant antigen were investigated in this communication. The effect of temperature was tested by heating aliquots (0.5 ml) for 20 minutes at 45 degrees C, 56 degrees C and 65 degrees C. The variant was found to be denatured at 56 degrees C while the control was denatured at 65 degrees C. The effect of pH was tested by assessing the quantity (Laurell technique) and electrophoretic mobility (two dimensional immunoelectrophoresis) of the antigen in a variety of buffers ranging in pH from 7.0 to 9.5. The quantity of antigen was variable both among variants and controls and the electrophoretic mobility of the variant antigen was faster at all pH's. Molecular weight differences between the variant and controls were not detected since the chromatographic profile of the variant was similar to that of the controls in Sepharose 6 B using a 0.02 M Tris-NaCL buffer at pH 7.0. The affinity of the antigen for human antibody was heterogeneous although the variant exhibited less affinity for one of the human antibodies but not the other. The inhibitory effect was more pronounced in serum than in plasma. Purified IGG, however, did not show any inhibition, as the residual antigen assayed by the Laurell technique, was similar to the expected values. This would imply that non-IgG plasmatic factors could also play a part in the observed inhibition.
|
63,441
|
Production of C and T bands in human mitotic chromosomes after heat treatment.
|
A modified thermal denaturation of human chromosomes in Hanks' solution at 91 degrees C produces highly contrasted C and T bands. This improved double-banding system is a good tool in the analysis of ring chromosomes, for which R banding is often inadequate, as it is exemplified.
|
63,445
|
Coal fires, industrial emissions and motor vehicles as sources of environmental carcinogens.
|
One of the most widely studied carcinogenic agents in the environment is the polycyclic hydrocarbon, benzo(a) pyrene. As a component of soot from the inefficient combustion of coal, its association with cancer can be traced back 200 years, but its possible relevance to lung cancer as a widely distributed air relevance to lung cancer as a widely distributed air pollutant has been investigated only during the past 25 years. Domestic coal fires have been shown to be important sources, and smaller amounts come from industrial sources and from motor vehicles. There is evidence now that the concentration of benzo (a) pyrene in large towns in Britain has decreased by a factor of about ten during the last few decades, as a result of changing heating methods and smoke control. In view of the overwhelming effect of cigarette smoking, it is difficult to determine whether the benzo(a)pyrene content of the air has had any importnat effect on the development of lung cancer, but careful analysis of trends in mortality may now throw some light on this. Among other materials with carcinogenic properties that may be dispersed into the general air, asbestos is the one that has been investigated most thoroughly. The association between exposure to asbestos and the development of lung cancer and mesothelioma of the pleura has been clearly demonstrated among people occupationally exposed to the dust, but as far as the general public is concerned, any risk may be limited to the immediate vicinity of major sources. These and other hazards demonstrated among occupational gropus serve as a warning however to maintain careful scutiny of urban air pollutants in relation to the acetiology of cancer.
|
63,451
|
An in vitro model of canine immediate-type hypersensitivity reactions.
|
Fragmented lung prepared from dogs cutaneously sensitive to ascaris antigen released histamine and a slow-reacting substance of anaphylaxis-like (SRS-A) material upon antigen challenge. Passive sensitization of fragments with serum obtained from ascaris-sensitive donor dogs enhanced the release of both substances; heating (56 degrees C for 4 h) destroyed the ability of the serum to enhance release. In passively sensitized tissues isoproterenol and papaverine inhibited the release of histamine and SRS-A; propranolol antagonized the effect of isoproterenol. Carbachol enhanced the release of both substances from passively sensitized lung wheras disodium cromoglycate and aminoguanidine were without effect. It is concluded that fragmented canine lung is a useful model for study of immediate-type hypersensitivity reactions.
|
63,454
|
Influence of Q- and G-banding on the Feulgen-stainability of human metaphase chromosomes.
|
In this paper, model experiments on chicken red blood cell nuclei are described concerning the influence of methanol-acetic acid fixation and irradiation at different wavelengths, with and without prior Atebrin staining on subsequent Feulgen-stainability. In addition, data are reported on the influence on Feulgen-stainability of Giemsa-banding procedures, illumination of unstained chromosomes at 220 and 515 nm and exposure of unstained and Atebrin-stained chromosomes to illumination at 440 nm. The ASG and especially the trypsin-Giemsa technique appeared to reduce markedly Feulgen-stainability. The same holds true for Atebrin fluorescence of chromosomes. The data are discussed in relation to their implications for the assumed cause of the Q- and G-banding phenomena. Techniques are described that allow reliable Feulgen DNA measurements of individual chromosomes after application of either G- or Q-banding.
|
63,455
|
An ultrastructural study of osmiophilia in the human rectum.
|
Rectal biopsies from subjects with a normal rectum and from patients with various forms of inflammatory bowel disease were studied by the prolonged osmication technique. No consistent ultrastructural differences were observed between these groups, but there were striking differences between individual epithelial cells in the same biopsy and between the epithelium and the cells of the lamina propria. The Golgi apparatus was demonstrated occasionally in the epithelium, often in endothelium. Endoplasmic reticulum, perinuclear cisterna and mitochondria were variably outlined. In plasma cells, there were striking differences in osmiophilia. The underlying mechanism of the different staining patterns is not clear. The findings do not appear to help in the differential diagnosis of inflammatory bowel disease nor to shed any new light on their underlying pathogenic mechanisms.
|
63,457
|
A comparison of polychromasia and reticulocyte counts in assessing erythrocytic regenerative response in the cat.
|
Three staining techniques were evaluated for use in assessing the erythrocytic regenerative responses in the cat. Using new methylene blue as a vital stain, the aggregate reticulocyte count closely corresponded to the reticulocyte count on air-dried smears stained with new methylene blue and to the polychromatophilic erythrocyte count on Wright's stained smears.
|
63,456
|
Histochemical detection of sialic acid residues using periodate oxidation.
|
The use of low concentrations of periodate for the detection of sialic acid residues in tissue sections has been investigated. Oxidation of aqueous solutions of sugar glycosides with 0.4 mM periodate revealed that sialic acid was oxidized more rapidly than other sugars found in glycoproteins. Sequential treatment of tissue sections with 0.4 mM periodate for 30 min followed by Schiff's reagent stained sialic acid residues but other sugar components were not stained under these conditions.
|
63,458
|
Relationship between changes in the translational apparatus and actinomycin production in Streptomyces antibioticus.
|
As previously reported (G. H. Jones, 1975), transfer ribonucleic acids (tRNA's) and ribosomes from actinomycin-producing cultures of Streptomyces antibioticus show a decreased ability to function in aminoacylation and translation as compared with the corresponding components from younger cells. Further, specific changes in the isoacceptor patterns are revealed when tRNA's from actinomycin-producing cells are compared with those of younger cells by reverse- phase column chromatography. A specific glycyl-tRNA species is eliminated from the reverse-phase profile of tRNA's from actinomycin-producing S. antibioticus cells as compared with younger cells. Changes in isoacceptor patterns were also observed for the amino acids methionine, valine, phenylalanine, and leucine. Actinomycin synthesis was inhibited by growing S. antibioticus cells in the presence of alpha-methyl-DL-tryptophan. Inhibition of actinomycin synthesis reversed the changes in tRNA observed in normally grown control cultures, although it had no demonstrable effect on the growth of the cells. Thus, tRNA from 48-h-old, alpha-methyl-tryptophan-grown cells had amino acid acceptor activity that was equal to or greater than that of tRNA from 12-h-old, normally grown cells. Similarly, the reverse-phase chromatographic pattern for glycyl-tRNA's from 48-h-old, alpha-methyl-tryptophan-grown cells was identical to that of the glycyl-tRNA's from 12-h-old, normally grown cells. In contrast, the ability of ribosomes from 48-h-old, alpha-methyl-tryptophan-grown cells to function in polypeptide synthesis in vitro was essentially identical to that of 48-h-old, normally grown cells. Ribosomes from 12-h-old, normally grown cells were severalfold more active in in vitro polypeptide synthesis.
|
63,459
|
The ovalbumin gene. In vitro enzymatic synthesis and characterization.
|
Using purified single-stranded ovalbumin complementary DNA (cDNAov) as a template for avian myeloblastosis (AM) virus reverse transcriptase, we have enzymatically synthesized a complete double-stranded cDNAov sequence. Our data suggests that many single-stranded cDNAov molecules contain short double-stranded sequences (hairpins) at their 3' termini capable of acting as primers for synthesis of complete double-stranded cDNAs. Optimum conditions for synthesis of the double-stranded cDNAov were found to be a high temperature (46 degrees) and a low salt concentration. Nevertheless, in all cases 40% of the initial single-stranded cDNAov molecules fail to prime for synthesis of a complementary double strand. Following synthesis, the second DNA strand is covalently linked to the first cDNAov strand as shown by analysis on alkaline sucrose gradients. The two strands have a high Tm on hydroxylapatite (89 degrees). These intact double-stranded cDNAov structures have a bouyant density in CsCl gradients of 1.700 g/cm3 and rapidly renature after heat denaturation with a C0t1/2 value of less than 2 X 10(-6) mol s liter(-1). All size classes of cDNAs, i.e. partial as well as complete transcripts of the mRNA, are capable of forming double-stranded structures. The closed loop of the double-stranded cDNAov could be opened with S1 nuclease. The denatured complementary strands of the cDNAov then renatured with the appropriate second order kinetics at a C0t1/2 value of 1.89 X 10(-3) mol s liter(-1). Using the enzyme terminal deoxyribonucleotidyltransferase to label to free 3'-terminal end of double-stranded [32P]cDNAov with 3H, we demonstrate a convenient procedure to study the site for restriction endonuclease cleavage within the ovalbumin gene.
|
63,460
|
Light-induced exchange of nucleotides into coupling factor 1 in spinach chloroplast thylakoids.
|
The method of centrifugation of chloroplast thylakoids through silicone fluid, previously used to estimate the uptake of solutes by thylakoids, is shown to be an excellent method for measuring binding of nucleotides to thylakoids. This binding, which is probably an exchange (Harris, D. A. and Slater, E. C. (1975) Biochim. Biophys. Acta 387, 335-348), is enhanced by light and is sensitive to uncoupling. Half-maximal binding of adenosine 5'-triphosphate (ATP) or adenosine 5'-diphosphate (ADP) at 10 mjM was reached within less than 0.1 s. With illumination times sufficient to elicit maximal binding, saturation of the site(s) is approached at 20 muM nucleotide and dissociation constants of 5 muM and 7 muM were calculated for ADP and ATP, respectively. At saturation, the binding corresponds to 1 mol/mol of coupling factor 1 or less. Although the light-dependent binding of ADP does not require Mg2+, that of ATP is markedly enhanced by Mg2+. A 10-fold molar excess of guanosine di- or triphosphate or adenyl-5'-yl imidodiphosphate had little effect on the binding. Adenosine 5'-phosphosulfate, a competitive inhibitor of phosphorylation with respect to ADP, decreases the binding. Thylakoids, previously illuminated in the absence of added nucleotides, retain the capacity to bind ADP or ATP in the dark long after the H+ electrochemical gradient has decayed. The conformation of coupling factor 1 in darkened thylakoids following illumination in the absence of added nucleotides may thus differ from that in thylakoids either illuminated in the presence of nucleotides or kept in the dark. Approximately 20% of the ADP bound to coupling factor 1 in thylakoids is converted to ATP by a 2-s illumination. Bound inorganic phosphate, derived either from ATP or from inorganic phosphate itself, serves as the phosphoryl donor. Bound ADP may, therefore, be of catalytic significance in the mechanism of phosphorylation.
|
63,463
|
Resolution in electron microscope autoradiography. III. Iodine-125, the effect of heavy metal staining, and a reassessment of critical parameters.
|
Resolution for 125I-labeled specimens under electron microscope (EM) autoradiographic conditions was assessed experimentally. With this isotope the size of the silver halide crystal was the most important resolution-limiting factor. Heavy metal staining such as is routinely used in preparing animal tissues for EM autoradiography produced an improvement in resolution of approximately 15-20%. For a 500-1,000-A biological tissue section fixed with OsO4 and stained with uranyl acetate, we obtained resolution (half distance, HD) values of approximately 800 +/- 120 A using Ilford L4 emulsion and 500 +/- 70 A using a Kodak NTE-type emulsion. General aspects of resolution-limiting factors and comparison with 3H and 14C values are discussed.
|
63,462
|
Treatment of pathological fractures of long bones excluding those due to breast cancer.
|
Seventy-two pathological fractures associated with tumors other than carcinoma of the breast in the long bones of the extremities of sixty patients were treated over a five-year period at Roswell Park Memorial Institute. Pain was relieved in 91 per cent of the patients treated by internal fixation, in 59 per cent of those treated by irradiation, and in 45 per cent of those treated by other means. Among patients with lower-extremity fractures, 61 per cent of those treated by internal fixation became ambulatory, whereas only 23 per cent of those treated by other methods were able to walk. Internal fixation of these pathological fractures appeared to be the best treatment.
|
63,464
|
The electrophysiological mapping of compartments within a mammalian cell.
|
The electrical properties of structures within an intact cell were examined by impalement with micropipette electrodes. Mean potential differences (PDs) measured from interphase HeLa cells showed that internal membrane-bounded compartments such as the nucleus, Golgi region, and the mitochondria were more negative than the cytoplasm with respect to an external grounding electrode. The nuclear PDs, unlike Golgi and cytoplasmic PDs, shifted during interphase and reached a peak value shortly before mitosis. The positioning of micropipettes was confirmed by electron microscope examination of marker solutions that were microinjected into specific intracellular regions. The combination of methods described here offers a new approach for the study of physiological events within intact, living cells.
|
63,465
|
Regular structures in membranes: the lumenal plasma membrane of the cow urinary bladder.
|
The ultrastructure of the lumenal plasma membrane of the cow urianry bladder has been studied in thin sections of glutaraldehyde- and glutaraldehyde-H2O2-fixed specimens, by negative staining and freeze fracture. A regular hexagonal array of particles confined to polygonal plaques 0-1-0-4-mum in diameter and separated by 0-02-mum interplaque areas is revealed by all 3 techniques. Cross-sections through particulate areas fixed with glutarayldehyde-H2O2 display a tetralaminar structure consisting of the usual approximately 8-nm-thick trilamellar unit membrane structure, on the external dense leaflet of which is located an additional approximately 4-nm-thick stratum which is occasionally resolved into a row of regulrly spaced approximately 4-nm-diameter particles. Non-particulate areas feature only the approximately 8-nm-thick trilamellar structure. Tangential sections reveal an hexagonal array of particles with a unit cell of approximately 16 nm. Four membrane faces can be revealed by freeze fracture and etching of membranes of the cow urinary bladder; 2 complementary split inner membrane faces (A and B) revealed by the cleaving process and the lumenal and cytoplasmic membrane surfaces exposed by etching. Face B, which belongs to the external membrane leaflet and faces the cytoplasm, displays plaques of particles arranged in a hexagonal lattice with a unit cell of approximately 16 nm. Face A, which belongs to the cytoplasmic membrane leaflet and faces the lumen, displays a complementary array of hexagonally packed pits. The hexagonally arranged particles also protrude into the lumenal membrane surface where they can occasionally be resolved into 6 approximately 5-nm-diameter subunits; the cytoplasmic surface appears smooth. Six approximately 5-nm-diameter subunits are also revealed in negatively stained preparations. The data are consistent with a model for the membrane in which the particles forming the hexagonal structure protrude above the lumenal membrane surface and also bridge most of the thickness of the membrane.
|
63,466
|
Interrelationships between Golgi, GERL and synaptic vesicles in the nerve cells of insect and gastropod ganglia.
|
In addition to demonstrating synaptic vesicles, staining with the zinc-iodide-osmium tetroxide (ZIO) method reveals the presence of positively reacting GERL membranes in association with the Golgi complex and lysosomes in the nerve cell bodies within ganglia from the locust Schistocerca gregaria and the gastropod molluscs, Limnaea stagnalis and Helix aspersa. A positive response to ZIO occurs in certain Golgi vesicles and saccules, in GERL (Golgi-endoplasmic-reticulum-lysosomes), in multivesicular bodies as well as residual bodies and in small vesicles and cisternae of axonal smooth endoplasmic reticllum (ER). The interrelationships between these organelles are considered in view of the similarity of the ZIO localization to phosphatase-rich sites in the neuronal perikarya and with respect to the possibility that components of the synaptic vesicles are formed in the Golgi region of the cell and migrate via the axonal smooth ER to the synaptic regions.
|
63,467
|
Thin-layer chromatography of some cationic dyes commonly used in histology.
|
A number of cationic dyes commonly used in histology may be conveniently and effectively analysed using the thin-layer chromatographic system of Marshall and Lewis. Commercial samples of Acridine Orange, Crystal Violet, Janus Green B,Methyl Violet, Neutral Red, Pyronin B, Pyronin Y(G), Safranin, Victoria Blue B and Victoria Blue 4R have been analysed with this system. All have been found to be complex mixtures of coloured components. Chromatographic data on these components are presented.
|
63,468
|
Androgens in patients with benign prostatic hyperplasia before and after prostatectomy.
|
Plasma androgens [testosterone (T), 17beta-hydroxy-5alpha-androstan-3-one (DHT), androst-4-en-3,17 dione(A), and dehydroepiandrosterone (DHEA)] as well as 17 hydroxyprogesterone were measured in a group of patients (age 60-80 yrs.) with benign prostatic hyperplasia (BPH) just before prostatectomy and compared to values obtained in subjects of similar age without signs of BPH. The most important difference was observed in the mean DHT level which was significantly (P less than 0.025) higher than in the control group; mean T and free testosterone levels in BPH patients were slightly higher (P less than 0.05) in the age group 70-80 yrs; whereas in age group 60-70 mean values were similar to those observed in normal controls. Mean A, DHEA and 17 OHP and E2 levels were not significantly different in BPH patients when compared to age matched controls. 2-5 months after prostatectomy, T and DHT levels were significantly higher than immediately preoperatively. The preoperative stress may have influenced the preprostatectomy values.
|
63,469
|
Delta5-androstenediol: kinetics of metabolism and binding to plasma proteins in normal men and women.
|
Using the constant fusion and single injection technique the metabolic clearance rates (mean +/- SEM) for delta5-androstene-3beta, 17beta-diol (delta5-idol) were measured for 19 normal men (1311 +/- 67 1/24 h) and 10 normal women (858 +/- 63 1/24 h). The constant infusion technique yielded values for the conversation ratios for the transformation of delta5-diol to several products: dehydroepiandrosterone (DHEA)/delta5-diol of 0.06+/-0.01 for men and 0.05 +/- 0.01 for women, of delta5-diol sulfate/delta5-diol of 0.45 +/- 0.04 for men and 0.52 +/- 0.03 for women and of DHEA sulfate/delta5-diol of 5.53 +/- 0.26 for men and 5.02 +/- 0.42 for women. The single injection technique yielded rate constants (units) and volumes of distribution (liters) for delta5-diol; Ki = 34.3 +/- 4.3 for men and 35.0 +/- 3.9 for women, K2 = 63.7 +/- 4.1 for men and 75.1 +/- 4.2 for women, V1 = 23.1 +/- 3.2 for men and 11.9 +/- 2.3 for women, V2 = 14.8 +/- 3.7 for men and 9.2 +/- 3.2 for women. The mean delta5-diol plasma concentration was 1.08 +/- 0.10 ng/ml for 12 men and 1.17 +/- 0.16 ng/ml for 9 women. (he calculated blood production rates for delta5-diol were 1357 +/- 117 mug/24 h for 12 men and 969 +/- 131 mug/24 h for 9 women. The per cent binding (equilibrium dialysis) was higher for women (94.9 +/- 0.3) than for men (93.0 +/- 0.2). Paper electrophoresis showed that significant fractions of 3H-delta5-diol migrated with both the beta-globulin and albumin fractions. Estrogen administration to two normal men increased the per cent binding of delta5-diol to plasma proteins and decreased the metabolic clearance rate towards the values found for normal women.
|
63,471
|
Interhemispheric neocortical connections of the corpus callosum in the reeler mutant mouse: a study based on anterograde and retrograde methods.
|
The tangential organization of the callosal system of interhemispheric connections, as judged by the distribution of axon terminals as well as by the distribution of cells of origin of callosal axons, is normal in the reeler mutant mouse. As in the normal animal connections between the two cerebral hemispheres are homotopic. In the reeler, as in the normal animal, medium-sized pyramidal cells are, numerically speaking, the principal cells of origin of the callosal system. These lie superficially in the cortex of the normal animal but deep within the cortex of reeler. Callosal terminals are most densely concentrated at the cortical level of the small and medium-sized pyramids in both reeler and normal animals. It is probable, therefore, that the same classes of neurons are interconnected by the callosal system in the normal and reeler mouse despite malposition of neurons in reeler. The patterns of intracortical distribution of terminals of callosal axons is evidently governed by the positions of their target cells.
|
63,472
|
The anatomical organization of the cerebello-olivary projection in the cat.
|
The cerebello-olivary pathway in the cat has been examined using orthograde and retrograde neuroanatomical tracing techniques. The orthograde transport of 3H-leucine from injection sites in the deep cerebellar nuclei labeled dentate and interpositus projections to the rostral two-thirds of the contralateral inferior olivary complex. These projections are topographically organized, with the dentate nucleus projecting to the principal olivary nucleus and the posterior and anterior interpositus nuclei projecting to the medial and dorsal accessory olives respectively. Fibers from the ventral half of the dentate nucleus terminate in the lateral bend and ventral lamina of the principal olive, whereas the medial and lateral parts of the dorsal half of the nucleus project to the medial and lateral regions of the dorsal lamina respectively. It is apparent that the more caudal parts of the interpositus nuclei project to areas of the medial and dorsal accessory olives near the caudal end of the principal olivary nucleus, whereas neurons in the more rostral parts of the interpositus nuclei project to the more rostral areas of the accessory olivary nuclei. A connection between the fastigial ncleus and the inferior olive could not be demonstrated. The retrograde transport of horseradish peroxidase (HRP) from injections sites in the inferior olive labeled cells throughout the contralateral dentate and interpositus nuclei. The labeled cells were especially numerous in the ventral parts of the dentate and posterior interpositus nlclei. These HRP-positive neurons were consistently small (10--15 mu) ovoid or spindle-shaped cells, with relatively large nuclei and light-staining Nissl substance. This evidence strongly suggests that the cerebello-olivary pathway originates from a population of small neurons in the dentate and interpositus nuclei and projects to specific, topographically defined areas in the contralateral inferior olive.
|
63,473
|
Epidermal changes in lichen planus.
|
Ultrastructural investigations in 15 patients with lichen planus (LP) revealed a multitude of epidermal changes. The most consistent findings were (1) multiplication, irregular folding or dislocation of the basal lamina, (2) fragmentation with degenerative changes of basal keratinocytes, (3) formation of numerous fibrillar Civatte bodies and, (4) presence of dyskeratotic elements. In addition, mitotic figures of keratinocytes and Langerhans cells were observed. These findings support the view that the primary event in LP represents an injury involving epidermal basal cells. Furthermore, the replacement of destroyed tissue seems to originate not only from the margin of the lesions or the skin appendages but also from unaffected cells within the LP papule.
|
63,478
|
Determination and identification of polycyclic aromatic hydrocarbons in smoked and charcoal-broiled food products by high pressure liquid chromatography and gas chromatography.
|
A high pressure liquid chromatographic procedure has been developed and applied to the analysis of polycyclic aromatic hydrocarbons (PAH's) in 70 samples of smoked food products commercially available in Canada, and in 6 charcoal broiled meats. In some cases a gas-liquid chromatographic procedure was used as a confirmatory technique. In the commercial samples PAH's were detected in approx. 70% of the samples. Total PAH's ranged from 0-141 ppb and individual PAH's from 0-38 ppb. With the charcoal-broiled samples, total PAH's and individual PAH's ranged from 0-164 ppb and 0-60 ppb respectively. These levels are similar to those observed in other countries.
|
63,479
|
[Alpha-1-antitrypsin, orosomucoid, transferrin and alpha fetoprotein in the amniotic fluid, Changes in concentration in normal and pathologic pregnancies].
|
In this article, which is a preliminary report, the authors determined amniotic fluid levels of alpha-I-antitrypsin, orosomucoid, transferrin and alpha-fetoprotein during complicated pregnancies with gestational ages of 31 to 42 weeks. These levels were compared with those observed during normal pregnancies. The clinical value of the variations of the glycoprotein levels is discussed.
|
63,505
|
Use of actinomycin D for the specific quenching of fluorescence of deoxyribonucleic acid in cells stained with acridine aminoderivatives.
|
Actinomycin D specifically quenches the fluorescence of acridine orange and quinacrine bound to deoxyribonucleic acid in cytologic preparations, but does not change the fluorescence of these fluorochromes bound to RNA. The following fluorescence-cytochemical applications of techniques based on these findings can be suggested: (a) distinction between deoxyribonucleic acid and ribonucleic acid; (b) detection of double-stranded virus ribonucleic acid; (c) approximate estimation of the lengths of A-T sequences in deoxyribonucleic acid molecules.
|
63,506
|
Immunohistochemical localization of melatonin in the rat Harderian gland.
|
Using fluorescence and double antibody techniques, melatonin was localized immunohistologically in the secretory cells of the Harderian gland of mature male rats. The presence and quantity of melatonin in the acinar cells seem to correlate with the amount of porphyrins inside the lumen. The specificity was proven by disappearance of yellow fluorescence after saturation of antibody with melatonin or after use of nonspecific antibody only.
|
63,507
|
Ultrastructural cytochemistry of biogenic amines in nervous tissue: methodologic improvements.
|
A new fixation method has been developed for localizing biogenic amines in nervous tissue. The method is a modification of the chromaffin reaction in which all fixation steps are buffered with mixtures of sodium chromate and potassium dichromate. In this way the fixation and cytochemical reaction are carried out almost simultaneously. Using the rat vas deferens as a model tissue, it was found that the preservation of electron dense (chromaffin) cores in the vesicles of adrenergic nerve terminals depended on several factors: a short primary fixation using low concentrations of aldehydes, the presence of the chromate/dichromate buffer during all fixation steps and, finally, a long incubation period in a slightly acidic (pH 6.0) solution of this buffer before postfixation in osmium tetroxide. Using this method it was possible to identify not only small and large dense-cored vesicles as storage sites for amines but also a tubular reticulum (neuronal endoplasmic reticulum), the latter especially in nerve terminals of mesenteric arteries and iris. Biogenic amines were also visualized in sympathetic ganglion cells and in the central nervous system e.g., supraependymal nerve terminals, tissues that up to now proved the most difficult in terms of amine localization. In all the tissues examined the cytochemical reaction was highly selective and present in well preserved tissue, which is a significant advance over previously available techniques. It therefore offers new opportunities for further studies on the role of biogenic amines as neurotransmitters.
|
63,509
|
A microspectrophotometric study of Papanicolaou-stained cervical cells as an aid in computerized image processing.
|
As part of a study of cytologic automation, microspectrophotometric investigation of Papanicolaou-stained cervical cells was performed, using a Leitz MPV-II scanning photometer connected to a PDP 8/F minicomputer. It was shown that the selection of one single wavelength may result in difficulties in detecting boundries between background and cytoplasm and/or between cytoplasm nucleus. A set of two wavelengths, 530 nm and 570 nm, were found to be optimal for the image processing of these cells.
|
63,510
|
Quantitation of mast cell heparin by flow cytofluorometry.
|
Mast cells can be automatically identified in a mixed cell population by flow cytofluorometry after Berberine sulphate staining. Volume specific counts of the total number of cells and number of mast cells, as well as frequency distributions of fluorescence intensities of mast cells, based on a large number of cells, can be rapidly obtained. Results obtained by microscope fluorometry of cells identified by phase contrast microscopy showviously published results it may be inferred that the fluorescence intensity of individual mast cells is proportional to mast cell heparin content. The automated cell counts correlated very well with manual hemocytometer counts. Both cell counts and the determination of mean mast cell fluorescence showed excellent reproducibility.
|
63,512
|
The blue reaction product in horseradish peroxidase neurohistochemistry: incubation parameters and visibility.
|
A blue reaction product is formed at sites that contain horseradish peroxidase (HRP) activity when benzidene is used as the chromogen. With neutral red as a counter stain, this method affords excellent visualization of both retrograde and orthograde axonal transport of intracerebrally injected HRP. The visibility of this blue reaction-product is better than the visibility of the brown reaction-product obtained in the commonly used diaminobenzidene procedures. Variations in incubation times and reagent concentrations resulted in significant differences in the extent to which transported HRP could be demonstrated with benzidene. One of these benzidene procedures demonstrated a wider extent of HRP transport than a representative diaminobenzidene procedure. The substantia nigra and the nucleus locus ceruleus did not display artifactual deposition of the blue reaction-product.
|
63,511
|
The identification of eosinophil colonies in soft-agar cultures by differential staining for peroxidase.
|
There has been a need to easily quantitate the incidence of eosinophil colonies within soft agar cultures. This has been realized by layering of the agar with benzidine dihydrochloride that permits detection of peroxidase activity in cells. Eosinophil colonies can be specifically identified by the addition to the substrate of potassium cyanide, an inhibitor of enzyme activity in neutrophils and monocytes. The enumeration of eosinophil colonies can be accomplished by scanning fresh or embedded cultures with low power magnification.
|
63,513
|
Mapping of the genetic control of murine response to low doses of the dinitrophenyl conjugates of ovomucoid and bovine gamma-globulin.
|
The antibody responses in mice to low doses of the DNP-conjugates of ovomucoid (OM) and bovine gamma-globulin (BGG) were measured for a number of inbred strains carrying independent and recombinant H-2 haplotypes. This permitted mapping the gene(s) controlling the response to low doses of OM (Ir-1-OM) within the I-A subregion of the H-2 complex. Similarly, it was possible to map the primary gene(s) controlling the response to low doses of BGG (Ir-1-BGG) within the I-A and/or I-B subregions. Further localization of the Ir-1-BGG gene(s) to the I-A or I-B subregion of the H-2 complex was not possible due to the ambiguous response of the B10.A(4R) strain of mice.
|
63,514
|
Relationship between beta2-microglobulin and cell-surface alloantigens of the mouse.
|
Molecular relationships between beta2m and other cell surface antigens (H-2, Tla, Ia, and Thy-1) were studied with the double immunofluorescence method. Cells were incubated with an antiserum against one antigen capped, and then tested with an antiserum against a second antigen. Capping of beta2m on thymocytes led to simultaneous capping of H-2 and Tla but not Thy-1 antigens; capping of H-2 and TIa (but not Thy-1) antigens resulted in capping of all beta2m detectable by the immunofluorescence method. Similarly, capping of beta2m on B or T lymphocytes resulted in capping of H-2 and vice versa. Ia antigens on B lymphocytes were not capped after the redistribution of beta2m. We conclude from these data that, in the cell membrane of thymocytes, virtually all the beta2m molecules are associated with H-2 and Tla, but not with Thy-1, and that on the cell surface of T or B lymphocytes, virtually all beta2m is associated with H-2 but not with Ia. We found no evidence of any significant free beta2m on either thymocytes or splenocytes.
|
63,515
|
Development of mast cells in vitro. II. Biologic function of cultured mast cells.
|
Mast cells were obtained by long term culture of rat thymus cells on rat embryonic fibroblast monolayers. Pure mast cell preparations obtained culture were incubated with 125I-labeled rat E myeloma protein to study receptors for IgE on their surface. When the cells were obtained after 35 to 45 days culture, the average number of receptors per mast cell was 100,000 to 400,000. An equilibrium constant of the binding reaction between their receptor and rat IgE was in the order of 108 M-1. The histamine content of the cultured mast cells was 0.2 to 5 mug/106 cells. The measurement of histamine content in mast cells recovered after different periods of culture suggested that the histamine content increased with maturation. Even after 45 to 50 days culture, the histamine content of cultured mast cells was significantly lower than that in rat peritoneal mast cells. The cultured mast cells were passively sensitized in vitro with rat IgE antibody against Nippostrongylus brasiliensis. The sensitized cells released histamine upon incubation with the antigen. It was also found that cultured mast cells released histamine upon exposure to compound 48/80. These results indicated that cultured mast cells have physiologic functions similar to those of normal rat mast cells, but they have not reached full maturation.
|
63,516
|
Conformational integrity of myoglobin after immunization with Freund's adjuvant.
|
The use of Freund's complete adjuvant for immunizing goats with myoglobin produces mainly antibodies directed against antigenic determinants present in the native protein. Only about 9% of the total antibodies produced are directed toward determinants not expressed in tha native molecule. This shows that neither emulsification nor the subsequent in vivo events leading up to the immune response appreciably perturb the conformation of the protein surface.
|
63,517
|
Amyloid-related serum protein SAA from three animal species: comparison with human SAA.
|
The amyloid-relates serum protein SAA has been isolated by gel filtration in 10% formic acid from three animal species: mink, mouse, rabbit. Sera used in the isolation procedure were obtained from animals in which high concentrations of SAA had been induced by treatment with LPS. The isolated SAA proteins had a subunit size similar to that of human SAA, with m.w. values ranging from 10,000 to 11,700 (estimated by gel filtration in 6 M guanidine-HC1) or 12,400 to 15,000 (estimated by SDS-PAGE). The m.w. studies and amino acid sequence data indicated that SAA and the amyloid fibril protein AA in the mouse, and probably also the mink, are related in the same way as in man, the two proteins having common NH2-terminal amino acid sequences and SAA being extended by 20 to 40 residues at the COOH-terminal end of the molecule.
|
63,518
|
The immunologic and molecular profiles of HLA antigens isolated from urine.
|
Human urine was shown to be a good source for the isolation of immunologically functional HLA-A9 antigens. The use of complex solubilization procedures can be avoided since the antigens are present in soluble form and are not complexes with membrane fragements. Purification in excess of 400-fold could be achieved by the application of cellulose ion exchange chromatography, isoelectric focusing, and acrylamide gel electrophoresis. The purified HLA-A9 antigen is composed of a glycoprotein of m.w. 38,000 and beta2-microglobulin, a peptide of m.w. 12,000. HLA-A9 antigens isolated from urine proved to be immunologically functional since they not only reacted specifically with anti-HLA-A9 alloantibody but also elicited anti-HLA-A9 xenoantibodies. These antibodies when covalently attached to Sepharose 4B specifically bound HLA-A9 antigens isolated from both serum and urine.
|
63,519
|
Isolation and characterization of canine secretory immunoglobulin M.
|
Canine secretory immunoglobulin M, isolated from both colostrum and bronchial secretions, contained the unique glycoprotein bound secretory component. The presence of this extra subunit accounted for the differences in size, quaternary structure, and antigenicity observed upon comparison of secretory immunoglobulin M with its serum counterpart. Approximately 90% of the isolated secretory immunoglobulin M contained covalently bound secretory component while, in the remainder of the population, secretory component was loosely attached and easily dissociated from the immunoglobulin. Following peptide bond cleavage with cyanogen bromide, the release of bound secretory component and J chain from secretory immunoglobulin M was not detected. Because cyanogen bromide cleavage of secretory immunoglobulin A results in the release of these subunits, differences in the primary structure of secretory immunoglobulin M and secretory immunoglobulin A must exist around the binding sites for secretory component and J chain.
|
63,520
|
Coincident hepatitis B surface antigen and antibodies of different subtypes in human serum.
|
Three patients with simultaneously detectable hepatitis B surface antigen (HBsAg) and antibody (anti-HBs) in their sera were studied for subtypes of HBsAg and anti-HBs. In each case anti-HBs was found to be directed to a different subtype than that of the circulating HBsAg, indicating that reinfection (or simultaneous infection) with a second subtype occurred.
|
63,521
|
Affinity in radioimmunoassay of antibody cross-reactive with carcinoembryonic antigen (CEA) and colon carcinoma antigen-III (CCA-III).
|
Several antisera raised against purified carcinoembryonic antigen (CEA) were evaluated for their content of antibody cross-reactive with colon carcinoma antigen-III (CCA-III). All antisera gave a reaction of partial identity between CEA and CCA-III and demonstrated a high titer in CEA radioimmunoassay (RIA). Between 50 and 70% of the CEA RIA activity was removed, however, by absorption with soluble CCA-III or adsorption onto CCA-III-containing immunoadsorbents. Immunoadsorbent retained antibody gave a line of complete identity between CEA and CCA-III. Purified CCA-III (2 mug) only partially depressed CEA binding by this common site antibody, whereas nanogram quantities of CCA-III inhibited the reaction between specific CCA-III antibody and radioiodinated CCA-III. In addition, low levels of CEA were equally effective in depressing CEA binding by the common site or CEA-specific antibody. The higher affinity in RIA of the common site antibody for CEA over CCA-III suggests that the common determinant expressed on CEA is stereochemically different from that on CCA-III. The results further demonstrate that interference by plasma CCA-III is not a significant factor in the measurement of CEA by RIA.
|
63,522
|
A micro-titer red-cell-linked-antigen-antiglobulin-test for DNP specific immunoglobulins.
|
A micro-titer red-cell-linked-antigen--antiglobulin test is described for the measurement of DNP specific immunoglobulins in mouse plasma samples.
|
63,524
|
Immunofluorescent localization of basement membrane in lesions of dermatitis herpetiformis.
|
Dermatitis herpetiformis (DH) is a blistering disease with a characteristic histology that includes papillary edema, neutrophilic papillary microabscesses, and development of subepidermal blisters. In spite of this pathologic sequence occurring entirely beneath the basement membrane zone, prior studies have indicated that the basement membrane, as defined by period acid-Schiff (PAS) or silver stains, lies at the floor of fully formed blisters or is destroyed by the disease process. To more accurately assess its location in primary lesions of DH, the basement membrane was stained using immunofluorescent techniques. Lesional skin from 5 patients with DH was used as substrate for indirect immunofluorescence with sera from patients with bullous pemphigoid (BP) and fluoresceinated antihuman IgG. The BP-stained basement membrane was attached to the roofs of early blisters, where it would be expected from the pathologic sequence of blister formation. PAS stains of the same or serial sections show the basement membrane to be in the roof or at the floor of the blisters. PAS stains of sections from formalin-fixed lesional skin, on the other hand, show the basement membrane to routinely lie at the blister floor, when not destroyed. The BP-stained epidermal basement membrane has greater anatomic and functional significance than either the PAS-or silver-stained basement membrane for two reasons: (1) it corresponds to a specific morphologic structure, the lamina lucida, a part of the epidermis, and remains attached to the rest of the epidermis unless destroyed; and (2) it is antigenic, capable of binding with BP antibodies.
|
63,525
|
Quantitative analysis of the major subdeterminants of hepatitis B surface antigen.
|
Antisera monospecific for subtyping of speciments of hepatitis B surface antigen (HBS Ag) were prepared by affinity chromatography. These sera were then used for quantitation of the a, d, and y subdeterminants of HBS Ag on a standard panel of sera and on 41 unselected sera containing HBS Ag. Although 25 of this latter group were completely monospecific for ad or ay, the remaining 16 sera showed degrees of cross-reaction with the heterologous antiserum. It is suggested that d and y subdeterminants are not infrequently present on the same particle.
|
63,526
|
A passive hemagglutination test for diagnosis of trench fever due to Rochalimaea quintana.
|
A passive hemagglutination test devised for diagnosis of trench fever was easily performed and highly sensitive and specific. Tanned sheep erythrocytes were sensitized with soluble antigen from Rochalimaea quintana. The test detected antibody in six of seven cases of primary infection and in four cases of late, relapsed trench fever. Titers of antibody ranged from 1:20 to 1:640. Although both IgM and IgG antibody to R. quintana were detected by passive hemagglutination, IgG appeared to be the major reactive antibody. Antigens involved in the reaction were two types of proteins, one inactivated at 50 C and 60 C and the other at 80 C and 100 C. Of 322 control samples of sera that were tested, only one reacted positively; thus, the test had a specificity of greater than 99%. The single positive reaction was in serum from a patient with Q fever. This finding suggests that, in an area where Q fever is endemic, this disease must be ruled out in the interpretation of a positive passive hemagglutination test. Sera should be tested routinely against tanned, unsensitized erythrocytes, since an occassional sample of serum may agglutinate unsensitized cells. Because of its sensitivity and specificity, as well as its simplicity of performance, the passive hemagglutination test shows promise as a useful procedure for serologic identification of both acute and past infection with R. quintana.
|
63,527
|
Histocompatibility antigens in patients with leprosy.
|
The frequencies of distribution of 25 histocompatibility antigens were determined in 92 Mexican patients with leprosy and compared with those in 315 Mexicans who did not have the disease. No statistically significant differences were found between the patients and the controls in regard to histocompatibility antigens, and subgroups with a significant difference could not be identified by division of the patients according to the density of Mycobacterium leprae or the presence or absence of cell-mediated immunity directed against antigens of M. leprae.
|
63,528
|
Radiation leukemia in C57BL/6 mice. I. Lack of serological evidence for the role of endogenous ecotropic viruses in pathogenesis.
|
The humoral immune response against endogenous ecotropic murine leukemia viruses (MuLV) was examined in irradiated and control C57BL/6 mice. Control mice developed antibodies against MuLV slowly throughout life. In contrast, within 2-3 mo after irradiation 90% of irradiated C57BL/6 mice had developed detectable antibodies against MuLV. The characteristics of this immune response, however, were identical in control and irradiated mice in terms of peak titers, specificity for endogenous ecotropic MuLV, and reactivity against the ecotropic viruses' glycoprotein (gp71). Moreover, the rate of appearance of antibodies against MuLV in irradiated mice and the peak titers were generally not affected by age at irradiation, dose of irradiation (two, three, or four treatments of 175 R), or bone marrow reconstitution. Although the ability of irradiation to accelerate the appearance of antibody in a population of C57BL/6 mice suggested activation of endogenous ecotropic MuLV, there was no apparent correlation between the appearance of this immune response or its persistence and the development of lymphoma. Thus, the incidence of lymphoma was comparable in mice that: (a) developed no immune response; (b) developed an immune response only transiently after irradiation; or (c) developed an immune response which persisted until death from lymphoma. Moreover, experimental conditions that alter the ability of irradiation to induce leukemia, such as age, dose, or bone marrow reconstitution did so without significantly altering either the rate of appearance of a humoral immune response to MuLV or its peak titers. The results, therefore, fail to demonstrate any seroepidemological relationship between endogenous ecotropic MuLV and radiation-induced leukemia.
|
63,529
|
Radiation leukemia in C57BL/6 mice. II. Lack of ecotropic virus expression in the majority of lymphomas.
|
The expression of endogenous ecotropic viruses in radiation-induced thymomas of C57BL/6 mice was examined. Competition radioimmunoassays for AKR MuLV gp71, p30, and p12 were used for viral antigen expression. 3 of 40 lymphomas had readily detectable ecotropic gp71 at levels of 95-689 ng/mg protein; the remainder of the tumors had no detectable gp71 (less than 1.0 ng/mg protein). 30 thymomas were characterized by the presence of MuLV p30 at levels of 1-10 ng/mg protein, levels that were comparable to those found in thymus extracts from age-matched, nonirradiated control. 10 tumors were characterized by having p30 levels of 10-30 ng/mg protein. In one tumor significant levels of AKR MuLV p12 were detectable. Since B-tropic and N-tropic viruses from C57BL/6 mice have glycoproteins (gp71) indistinguishable from AKR MuLV gp71 and the N-tropic virus had a p12 serologically identical to AKR MuLV p12, these results demonstrate that overt endogenous B-tropic virus was detectable in 2 of 40 thymomas and endogenous N-tropic virus was detectable in 1 of 40 thymomas. The lack of overt expression of gp71 or p12 was also confirmed by cytotoxicity assays using monospecific antisera to these viral proteins. Radiation-induced lymphomas were also examined for the presence of reverse transcriptase after chromatography of tissue extracts on poly G-Sepharose. One tumor, which was characterized by the lack of gp71, also had no detectable reverse transcriptase; whereas one tumor with gp71 was characterized by readily detectable levels of reverse transcriptase in cellular extracts. The presence of viral RNA was examined using AKR cDNA. Low levels of RNA capable of hybridizing with AKR cDNA were found in age-matched, nonirradiated mice; these hybrids had Tm's of 72 degrees C, while hybrids with AKR MuLV 70S RNA had Tm's of 80 degrees C. In 1 of 12 thymomas the concentration of hybridizable RNA and the Tm of the hybrids were identical to control values. In 9 of 12 thymomas the concentration of hybridizable sequences increased approximately three-to fivefold and the Tm of these hybrids varied from 73 to 75 degrees C. In 1 of 12 thymomas the concentration of hybridizable sequences increased over 100-fold, hybridized completely with AKR MuLV cDNA, and the hybrids had Tm's of 79 degrees C. This thymoma was also characterized by the presence of the AKR MuLV type of gp71 and p12. One tumor was characterized by a 10-to 100-fold increase in hybridizable sequences, which only partially hybridized with AKR MuLV cDNA, and hybrids had a Tm of 73 degrees C. This tumor was characterized by the presence of AKR MuLV gp71 but not AKR MuLV p12. The results taken together demonstrate that overt endogenous ecotropic virus expression is only rarely detectable in radiation-induced thymomas of C57BL/6 mice.
|
63,530
|
The specificity of cellular immune responses II. The structure of antigenic determinants leading to T-lymphocyte stimulation.
|
T cells from guinea pigs immunized with the hapten 2,4-dinitrophenyl (DNP)-coupled directly to mycobacteria are of interest since they recognize and respond to DNP conjugated to many but not all carriers. The experiments reported here further analyze the structure of the complex, chemically defined antigenic determinants recognized by such T cells. These antigenic determinants can have DNP coupled either to the xi-amino group of lysyl residues or to the hydroxyl group of tyrosyl residues. Furthermore, essential contributions to the determinant recognized by such T cells are made by amino acid residues to which the hapten is not attached. Such residues are thought to be close to the hapten group itself, since introducing a small spacer between hapten and carrier prevents recognition. The hapten itself is also recognized and discriminated from other haptens with great precision by these T lymphocytes. The strain of guinea pig immunized affects the precise specificity characteristics of the responding T cells, in a way that may reflect the activity of histocompatibility-linked immune response genes. Finally, the characteristics of the immunogen have been studied. It is thought that the lipid content of the mycobacteria may be critical in inducing the hapten-reactive T cells, and this is supported by finding similar responses in T cells from guinea pigs immunized with DNP protein to which lipid has been covalently attached. Thus, the T-cell population being studied, while recognizing haptens with great precision, appears to require a larger determinant for activation than do hapten-specific B lymphocytes.
|
63,532
|
Some properties of antisera to serum amyloid A protein (SAA): inhibition of precipitation by complexing of SAA to albumin.
|
Three potent rabbit antisera to human serum amyloid A protein (SAA) appear to be directed exclusibely to the carboxy terminal region not shared with the tissue amyloid A protein. Since binding to albumin completely blocks the reaction of these antisera with the antigen, and since SAA exists in serum complexed to albumin, the anti-SAA cannot be used to detect or quantitate this serum component. The possibility that similar problems will be encountered with immunoassays for molecules that exist complexed to other proteins is discussed.
|
63,531
|
The specificity of cellular immune responses in guinea pigs. III. The precision of antigen recognition by T lymphocytes.
|
T lymphocytes from guinea pigs immunized with 2,4-dinitrophenyl (DNP) derivatives of mycobacteria respond to a variety of DNP conjugates. Preincubation of such cells with a given DNP conjugate under conditions which lead to the inactivation of responding cells causes a loss of the response to that conjugate, but has little effect on the response to DNP coupled to unrelated carriers. Thus, the responses of such cells to a variety of DNP conjugates can best be explained by the presence of a mixture of highly specific cells each responding to a different antigenic dterminant rather than by the presence of T cells with specificity limited to the hapten itself. Furthermore, the activity of T cells from DNP-mycobacteria-primed donors could not be blocked by a variety of nonstimulatory DNP conjugates. This suggests that while such T cells clearly recognize DNP with great precision, the receptor does not contain a very high affinity site for the hapten. A possible model for such a T-cell receptor is discussed.
|
63,533
|
Genetic control of the immune response to staphylococcal nuclease. IV. H-2-linked control of the relative proportions of antibodies produced to different determinants of native nuclease.
|
The relative proportions of antibodies of different specificities within antisera raised to native staphylococcal nuclease have been studied in several strains of mice in which the antibody response has been shown to be under H-2-linked Ir-gene control. A method was developed in which binding to different radiolabeled fragments of nuclease was titrated against increasing fragment concentration until the binding capacity of the antiserum for that fragment was saturated. In comparing the low responder (H-2b) strain C57BL/10 with its congenic high responder counterpart B10.A (H-2a), it was found that the two strains made markedly and reproducibly different proportions of antibodies to different determinants on native nuclease. Since these two strains differ only at H-2, and therefore have identical immunoglobulin structural gene repertoires, we conclude that H-2-linked Ir genes can control the response to different determinants on the same antigen molecule independently of one another. This result suggests a possible role of H-2-linked genes in the selection of specific B cells.
|
63,535
|
Qualitative patterns of protein synthesis in the mouse oocyte.
|
Mouse oocytes were found to synthesize proteins actively at the germinal vesicle, metaphase I, metaphase II, and pronuclear (6 hours post-fertilization) stages. The qualitative pattern components being synthesized in vitro, as demonstrated using polyacrylamide gel electrophoresis, changed throughout maturation and fertilization. Oocytes were arrested at metaphase I by greater than 0.1 mug/ml cycloheximide or actinomycin D. The protein pattern in oocytes cultured in the presence of actinomycin D progresses to a metaphase II pattern in spite of the nuclear maturation arrest, indicating a dissociation between meiotic maturation and the changes in the pattern of proteins synthesized at different stages of maturation.
|
63,534
|
The Fc receptor on thymus-derived lymphocytes. IV. Inhibition of binding of antigen-antibody complexes to Fc receptor-positive T cells by anti-Ia sera.
|
Treatment of splenic T lymphocytes with anti-Ia antiserum inhibits the binding of antigen-antibody (AgAb) complexes to the majority (less than 50%) of Fc receptor-positive (FcR+) T cells. A similar inhibition was observed with anti-H-2D and anti-H-2K sera but not with anti-Thy 1.2. Despite the presence of Ia determinants on peripheral T cells, as established by the inhibition of AgAb binding, Ia could not be detected on peripheral T cells by immunofluorescence assays. Data obtained with the AgAb-binding inhibition assay indicate that determinants controlled by loci mapping in the I-A and I-C, S, or G regions are present on the FcR+ T cells. Evidence is presented that subpopulations of T cells within the FcR+ T-cell population may be distinguishable on the basis of which I-region-controlled determinant is expressed. The data are discussed in terms of phenotypic and functional heterogeneity of T lymphocytes.
|
63,539
|
A comparison of four methods used to concentrate Rous sarcoma virus from tissue culture fluids.
|
Three methods of pelleting, pelleting followed by Pronase treatment, polyethylene glycol (PEG)-Pronase, and diaflo ultrafiltration (diafiltration) were used to concentrate RSV(RAV-1) from tissue culture fluids. Sucrose-gradient fractions containing virus preparations which had been concentrated by diafiltration or pelleting were heavily contaminated with amorphous debris. This debris was not present in similar, gradient-purified preparations that had been concentrated by the PEG-Pronase or pellet-Pronase methods. Maximum recovery of radiolabelled virus particles and virion-associated RNA-dependent DNA polymerase activity was obtained in gradient fractions containing virus concentrates prepared by the pellet-Pronase and PEG-Pronase methods. Although there were slight differences in recovery by these two methods, the advantages of the PEG-Pronase method make it the preferred method, especially when large volumes of tissue culture fluids are used.
|
63,540
|
Effects of a memory aid of the three types of conservation in institutionalized retarded children.
|
Qualitative identity, quantitative identity, and equivalence conservation were assessed in 60 retarded boys and girls in three groups (MAS 5.4,6.3, and 7.5)9 Half of the Ss were provided a memory aid while the other half were not. The memory aid did not facilitate conservation on any of the tasks. The order of task difficulty found was qualitative identity, quantitative identity, and equivalence conservation. These data were discussed in terms of memory deficits and factors contributing to conservation and M.A.
|
63,541
|
Neuron culture from adult goldfish.
|
Neurons and glia from the central nervous system of the adult teleost Carassius auratus have been grown as explant cultures of minced brain tissue and as trypsin dissociated cells. These cultures exhibit extensive neurite growth from two neuronal types, have organotypic ultrastructure, and contain electrically active cells. Autoradiographic data indicate that these neurons do not divide in culture, and histological evidence suggests that some mature neurons survive explantation and regenerate processes. However, explantation of brain fragments not containing undifferentiated cells, localized in the ventricular and subventricular zones in the brains of fish, resulted in mesenchymal and glial cell cultures only. Therefore, a contribution to the population of cells in culture by undifferentiated cells must be considered. The cultured neurons remained viable for at least 19 weeks and ultrastructural and electrophysiological data indicate synaptic interaction between cells in explant cultures.
|
63,543
|
Isoelectric focusing and electrophoresis of the CSF proteins in tremor of different origins.
|
The CSF proteins have previously been very little investigated in the cerebellar syndrome of chronic alcoholism and in essential tremor. Such studies have been carried out more thoroughly by electrophoretic methods in Parkinson's disease but generally with normal results. In the present investigation the CSF proteins were examined by isoelectric focusing and quantitative paper electrophoresis in 10 patients with the cerebellar syndrome of chronic alcoholsm, 12 patients with Parkinson's disease and 16 subjects with essential tremor. Abnormal CSF proteins of very similar appearance were found on isoelectric focusing in the acidic pH interval 5.6-5.8 in 80% of the patients with the cerebellar syndrome of chronic alcoholism. In Parkinson's disease the most common aberration was evidence of nonspecific blood-CSF-barrier damage which occurred in half of the patients. In only 17% of these cases did other alterations appear, situated in the pH range alkaline to pH 5.8. Abnormal CSF proteins were found in 94% of the patients with essential tremor. The aberrant proteins appeared in both the acidic and alkaline pH regions, most frequently with anisoelectric point at pH 5.9, 7.2 and 9.3. There was a considerably higher frequency of CSF protein abnormalities in different pH ranges in patients with tremor of more pronounced degree as compared to those with only mild symptoms. The electrophoretic examinations failed to show any conclusive alterations. Barrier-damage patterns of mild or moderate degree or slightly increased levels of CSF beta1-globulin were occasionally found in all 3 diseases. The results indicate that isoelectric focusing of the CSF proteins may be of diagnostic value in the cerebellar syndrome of chronic alcoholism and in essential tremor but does not reveal any characteristic abnormalities in Parkinson's disease.
|
63,550
|
Steroidal compounds (injectable and implants) affecting spermatogenesis in men.
|
The effect of androgen and different progestins on spermatogenesis was studied in young men with subfertility, prostatovesiculitis and haematospermia, and in older men with benign hypertrophy of the prostate. The compounds (testosterone, testosterone oenanthate, ethinyl oestradiol, megestrol acetate, ethinyl norgestrienone and Depo-Provera) were administered intramuscularly, orally or as subcutaneous silastic implants.
|
63,551
|
Protein-binding polyhedral boranes.
|
A series of polyhedral borane derivatives containing protein-binding functional groups has been synthesized. Problems encountered in earlier studies (low incorporation levels, gross precipitation of conjugates) have been overcome by including a water-solubilizing gluconamide group in the structure. This modification has allowed high levels of boron to be covalently bound to HGG, forming a completely water-soluble conjugate.
|
63,552
|
Antenatal diagnosis of trisomy 13 with unexpected increase in alpha-feto protein.
|
A 24-year-old woman who had previously given birth to an infant with Down's syndrome was shown by chromosomal analysis of the liquor amnii to be carrying an infant with trisomy D. Routine examination of serum and liquor alpha-feto protein (AFP) in the antenatal period showed unexpected high levels of both, consistent with a neural tube defect. The fetus, however, did not have evidence of a neural tube defect but had scalp defects which were presumed to have allowed the leakage of AFP from the fetus into the liquor amnii and hance into the maternal serum.
|
63,553
|
A serotyping system for Clostridium welchii (C. perfringens) type A, and studies on the type-specific antigens.
|
A serotyping scheme for Clostridium welchii (C. perfringens) type A employing 57 antisera has been used to investigate the epidemiology of 153 food-poisoning outbreaks and 32 cases of gas gangrene and other clinical infections. Respectively 65% and 59% of the isolates were typable, and in 55% of the food-poisoning outbreaks the causative serotypes were established. Isolation and reporting methods that would render the typing scheme of even greater epidemiological value are described. The type-specific antigen was shown to reside in the capsule and to be lost from strains that had become rough. Development of roughness and its prevention are described. A great range of antisera and an internationally acceptable serotyping scheme is expected after integration of this set with those developed independently in America and Japan.
|
63,554
|
Xenotropic properties of an isolate from murine Rauscher leukemia virus in primates.
|
Murine Rauscher leukemia virus (MuRLV) from BALB/c plasma consisting of a mixture of an ecotropic and a xenotropic virus could be separated out by a selection process when propagated in human and simian cell cultures. This hypothesis is supported by obtaining consistently lower infectivity titers of human cell propagated RLV in human and simian cells as compared to MuRLV propagated in mouse cell cultures. Furthermore, RLV passaged in a simian cell culture failed to replicate in mouse cells, had a wide host range, was able to rescue Moloney sarcoma genome, possessed murine type C group-specific antigen, and was neutralized by anti-HRLV. Its reverse transcriptase was strongly inhibited by antiserum to MuRLV enzyme; however, antiserum to woolly monkey enzyme also inhibited (30%) its reverse transcriptase, suggesting some difference in antigenic properties. Inoculation of this virus in rhesus monkeys was inconclusive.
|
63,557
|
Carcinogenicity of aflatoxin B1 in rhesus monkeys: two additional cases of primary liver cancer.
|
Three of 42 (7%) monkeys given aflatoxin B1 (AFB1) for longer than 2 years have developed primary malignant neoplasms of the liver. Liver biopsies performed at intervals during aflatoxin administration revealed that neoplasia was preceded by pathologic lesions of the liver, including toxic hepatitis, proliferation of pseudotubules, and hyperplastic nodules. Serum alpha-fetoprotein levels, monitored in one of the monkeys by radioimmunoassay, paralleled tumor growth and recurrence of the hepatocellular carcinoma. Normal serum alpha-fetoprotein levels were noted for a monkey with hemangioendothelial sarcoma. Our results implicate AFB1 as a liver carcinogen in monkeys and add additional support to the hypothesis that humans exposed to this substance may be at risk of developing liver cancer.
|
63,558
|
Interaction analysis of selective and nonselective cell-mediated cytotoxicity.
|
The coexistence of selective and nonselective cytotoxic cells in effector suspensions required a method of separating the two effects before specificities in cell-mediated cytotoxicity could be investigated. A method of analysis was derived which used the average cytotoxicity for each effector and target to estimate selective and nonselective cytotoxic effects. The analysis clearly detected specificity in tests of cell-mediated lympholysis, and application to tests of cell-mediated cytotoxicity on cultured human tumor cells showed that selective reactions were found.
|
63,559
|
Host response to tumor-associated fetal antigens: kinetics and components.
|
Using a colony-inhibition bioassay that measures the contribution of the host response in transplantation immunity to tumor-associated fetal antigens (TAFA), I evaluated the occurrence of TAFA during different developmental stages of murine fetal liver cells. A maximum concentration of TAFA was present at approximately 15 days' gestation. A similar age-equivalence phase of gestation was also found in pig fetal liver. Host-response kinetics to TAFA were examined, and results indicated a similar pattern of activity for tumor- or fetal-immunized groups with a transient immune suppression in the middle of the study period. I detected specific antibodies generated by tumor and fetal cell immunization by a complement-dependent serum microcytotoxicity assay. The specificity of the reaction was evaluated further by absorption studies that demonstrated specific cross-reactive antibodies to fetal and tumor cell targets. Adoptive transplanted immunity to TAFA was indirectly evaluated by a modified Winn assay which indicated that a cellular immune mechanism was an important component of the host response to TAFA.
|
63,560
|
In vitro induction of tumor-specific immunity. II. Activation of cytotoxic lymphocytes to murine oncofetal antigens.
|
The presence of oncofetal antigens (OFA) on a wide variety of murine tumor cells was demonstrated to a totally in vitro system of cellular immunity. Nonimmune spleen lymphocytes were cocultivated with irradiated syngeneic fetal liver cells and, at various times after initiation of culture, were tested for the presence of cytotoxic lymphocytes (CL) by 51Cr-release assay with labeled tumor target cells. Significant cytotoxic activity was regularly detected after such culture, whereas only minor levels appeared in control cultures of spleen lymphocytes with irradiated syngeneic spleen cells. Specificity of the reaction was assessed by inhibition tests in which nonlabeled cells were admixed to the CL and 51Cr-labeled tumor targets. Fetal liver cells gave significant inhibition; however, no inhibition was found with adult spleen cells. Various tumor types gave inhibition, and fibrosarcomas were more effective than plasmacytomas or lymphomas. The results suggested that all tumor types tested possess such OFA, as well as their unique or virus-associated, tumor-associated transplantation antigens, and that the in vitro system permits a more active response to the tumor-associated OFA than that observed in in vivo studies.
|
63,561
|
Induction of tumors in Syrian hamsters by a human renal papovavirus, RF strain.
|
Injection of RF virus (RFV), a papovavirus isolated from human urine, into newborn Syrian hamsters induced subcutaneous sarcomas in 50% of the recipients with 18- to 48-week latent periods. Transplantation of 2 X 10(6) primary RFV-induced tumor cells into weaning hamsters caused tumors in 100% of the recipients within 1-2 weeks. Continuous tissue culture cell lines were established from two primary tumors; one of these was transplantable. An in vitro-transformed continuous cell line (RF-194) obtained by infection of primary hamster embryo fibroblasts with RFV was transplantable in weaning hamsters. Neither infectious RFV nor virion antigens were detected in transformed cells. No RFV was recovered when transformed cells were fused with permissive, human embryo kidney cells by means of inactivated Sendai virus. Immunoperoxidase staining was used to show that all three RFV-transformed cell lines contained an intranuclear T-antigen closely similar to that of simian virus 40(SV40)-infected cells. Most hamsters (84%) with primary or transplanted RFV tumors responded with antibodies that reacted with RFV T-antigen and the T-antigen of SV40-infected cells. Likewise, hamster antisera against SV40 T-antigen cross-reacted with RFV T-antigen. Adsorption of RFV T-antisera with an excess of lyophilized SV40-transformed cells removed all detectable activity against SV40 T-antigen but left significant activity against RFV T-antigen. The reciprocal adsorption produced an antiserum spedicic for SV40 T-antigen. Thus human and simian papovavirus T-antigens were related but immunologically separable.
|
63,562
|
Effect of ethidium bromide on transplanted virus-induced tumor cells.
|
Ethidium bromide (2,3-diamino-5-ethyl-6-phenylphenanthridinium bromide) significantly inhibited the RNA-dependent DNA polymerase of types A and C particles isolated from transplanted adenovirus 12-induced tumors of CBA mice. It was also cytotoxic for an established in vitro line of adenovirus 12-induced tumor cells of CBA mice and caused cell death, inhibition of [3H]thymidine uptake, and a significant reduction of cells in metaphase. Ethidium bromide significantly inhibited the in vivo growth of transplanted adenovirus 12-induced tumor cells of CBA mice, simian virus 40-induced tumor cells of hamsters, and murine leukemia virus-induced lymphoma cells of BALB/c mice. The compound may have exerted the antitumor activity by selectively affecting oncornavirus in the tumor cells.
|
63,563
|
Detection, quantitation, and characterization of the major internal virion antigen of the bovine leukemia virus by radioimmunoassay.
|
The major internal polypeptide of the bovine leukemia virus (BLV) was purified to homogeneity with the use of gel filtration and affinity chromatography. Like previous results, the protein had a molecular weight of 25,000 daltons as determined by electrophoresis in polyacrylamide gels with sodium dodecyl sulfate. More than 90% of the 125I-labeled protein was precipitated by bovine sera that reacted in immunofluorescence tests with acetone-fixed BLV-infected cells. In contrast, minimal precipitation (less than 5%) was observed with sera from 36 cattle in leukemia-free herds; these sera, negative by immunofluorescence, included six samples that had high titers of antibodies to the foamy-like bovine syncytia virus (BSV). Antisera prepared against several other oncornaviruses or the Mason-Pfizer monkey virus (M-PMV) did not bind the BLV p25 protein. Conversely, the labeled p30 polypeptides of several oncornaviruses tested did not react with bovine sera that had high titers of antibodies to BLV p25. Competitive radioimmunoassay(s) (RIA) also failed to detect cross-reactions between BLV p25 protein and the internal polypeptides of other mammalian and avian oncornaviruses, M-PMV, or foamy-like BSV. The RIA for BLV p25 antigen was also highly sensitive and specific for the detection and quantitation of the antigen in virus preparations and cell homogenates.
|
63,564
|
Safety of viral vaccine cell substrates: a reevaluation.
|
Primary cultures of African green monkey kidney and rabbit kidney as well as diploid cell lines WI-38 and DBS-FRhL-2 were examined for evidence of tumorigenicity and latent RNA tumor viruses. Cells inoculated into immunosuppressed newborn hamsters and rhesus monkeys were not tumorigenic. Cells treated with 2'-deoxy-5-iodouridine to induce the production of latent viruses were examined by electron microscopy, density gradient centrifugation, and the reverse transcriptase enzyme assay. No evidence was found for RNA tumor viruses by the biochemical or biophysical methods used. The results indicated that each type of mammalian cell currently used in the production of virus vaccines would be acceptable for these parameters of safety if similar control procedures were applied at the time the vaccines were manufactured.
|
63,565
|
Potentiation of cytotoxic T-cell function by virus.
|
Inoculation of C57BL/6J mice with allogeneic P815 mastocytoma cells in the presence of simian virus 40 (SV40), a DNA tumor virus, led to an enhanced cytolytic T-cell response to P815 in vivo. Cytotoxic function was also augmented if SV40 was given subsequent to a primary immunization, even when mice were given a suboptimal dose of immunizing cells. Although SV40 increased the cell-mediated immune response to allogeneic cells, it did not enhance the antibody response to the soluble antigen dinitrophenyl bovine gamma-globulin, a helper T-cell-dependent response. Thus it appeared that SV40 had a selective adjuvant effect on lymphocyte subpopulations, since it increased cytotoxicity but not helper T-cell function.
|
63,567
|
Immunofluorescent localization of alpha fetoprotein in yolk sac carcinomas of the rat.
|
alpha-Fetoprotein (AFP) was demonstrated by the immunofluorescent antibody staining technique in 1 primary and 3 transplantable yolk sac carcinomas of rats. AFP was observed only in structures with a characteristic endodermal appearance. This protein was not detected in embryonal carcinoma cells.20
|
63,566
|
Role of divalent ion complex formation in pyran--inhibition of nucleic acid biosynthesis.
|
The degree of inhibition of mammalian DNA-dependent RNA polymerases I and II and Moloney leukemia virus RNA-dependent DNA polymerase by pyran copolymer was dependent on the concentration of the divalent cation cofactor in the reaction mixture. Inhibition was completely blocked by an excess of divalent cations. It was concluded that pyran inhibited these enzymes by complexing with the essential divalent cation cofactor.
|
63,571
|
Combined cystometric, sphincter electromyographic and uroflowmetric studies before and after transurethral resection of the prostate.
|
Detrusor and urethral function was studied in 10 patients before and 3 months after transurethral resection of the prostate by means of flowmetry, and simultaneous gas cystometry and integrated sphincter electromyography. THE PATIENTas cystometry and integrated sphincter electromyography. The patient had no clinical signs of neurological disease. Six had neurogenic exaggeration of the detrusor reflex in the preoperative studies. In 3 patients changes in the detrusor reflex were found postoperatively. Postural changes in detrusor reflex excitability were encountered preoperatively and postoperatively. The preoperative finding of detrusor hyperreflexia in the majority of the patients is ascribed to lesions in the detrusor reflex organization at 2 anatomical sites: 1) a subclinical lesion of the cerebral circuits of the detrusor reflex control owing to arteriosclerosis and 2) an increase of sensory detrusor-reflex triggering stimuli from the morphologically changed prostatic urethra. The study calls for diagnostic techniques for delineation of minimal cerebrospinal impairment and objective assessment of the sensory innervation of the urethra.
|
63,573
|
The Gibbons indwelling silicone ureteral stent catheter.
|
A method is described to facilitate the placement of the Gibbons indwelling silicone ureteral stent catheter using 2 ureteral catheters. The small catheter is placed within the silicone stent and the larger one is placed over the smaller catheter, fixing the ureteral stent within the obstructed ureter.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.