http___www.telegram.hr_zivot_znanstvenici-su-uspjeli-stvoriti-prvi-funkcionalni-misic-iz-stanica-koze-i-to-bi-moglo-biti-dosta-vazno__1.xml
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Stem Cells Background In brief, stem cells refer to cells that have the potential to differentiate into other cell types. This differs from most other cells, such as skin cells, which are incapable of changing into a different cell type. For example, neurons cannot turn become liver cells, but stem cells can turn into either as a result of environmental surroundings. Stem cells offer a high potential in clinical and scientific applications that may produce information about human development and human tissue diseases. These versatile cells form all of the tissues and organs that make up the complexity of the human bodies, starting as a single cell upon conception. Stem cells are the building blocks of life and can repair damaged cells and replace dead ones. In theory, stem cells are able to divide infinitely in order to replenish cells for the host as long as it is alive. Stem cells are undifferentiated cells with the ability to self-divide for renewal of its own type, but also can self-divide and differentiate to become specialized under various conditions. The most crucial application of stem cells in an organism, however, is the production of cells and tissues that can be used to replace damaged or malfunctioning tissues due to diseases and injuries. Blood contains red and white blood cells, plasma and platelets, and are derived from stem cells in bone marrow. Stem cells retain the capacity of mitotic cell division and are divided into three basic types: totipotent, multipotent, and pluripotent. Totipotent stem cells have the capability of differentiating into all types of cells in the body. Multipotent stem cells are those that differentiate into a small number of different cell types, while pluripotent stem cells may develop into any type of cell in the body except those needed to develop fetal growth. Cell differentiation is a crucial topic in cancer research, as it is often in differentiation that cells turn down the path to tumor formation. Differentiated human stem cells provide an excellent starting ground for pharmaceutical screening. Stem Cell Involvement in Disease Cellular differentiation occurs as cells are programmed to create intracellular patterns depending on chemical signaling. In an embryo, such cells are directed to differentiate or become various tissue cells such as fat cells, nerve cells, muscle cells, epithelial cells, and so forth. A stem cell is uncommitted until instructed what to do. Embryonic (totipotent) stem cells are found in early embryo development and have the capacity to differentiate, or morph, into any of the 200 types of specialized cells found in the human body. Stem cells found in bone marrow are capable of producing different types of blood cells every second. An adult (multipotent) stem cell is found in various tissues and is able to multiply as part of maintenance and renewal. Embryonic stem cells cultured in laboratory settings may be coaxed to divide multiple times. Such cells can also be coaxed into developing into muscle cells, nerve cells or blood cells. As a result of their abundant abilities, stem cells have the potential to help individuals affected by diseases such as Parkinson’s and leukemia, as well as heart attacks and paralysis. Adult stem cells have been used to create bone, nerve, and cartilage cells. However, adult stem cells are not as versatile as those found in embryonic tissues due to differentiation. Current research and development is also delving into umbilical cord blood stem cells to use as future cellular and tissue structures. Pluripotent stem cells may be cultivated from human embryonic tissues and used to create stem cell lines that are grown in a laboratory for research purposes. Such stem cell lines enable researchers and scientists to utilize these cultured stem cells without needing to isolate stem cells from their hosts. Stem cell lines may be grown in laboratory environments and frozen for storage. Stem cell research has the potential of offering cures for many diseases, as well as for generating new cells that may be used to replace cells in individuals suffering from leukemia, cardiovascular disease, diabetes, and even spinal injuries. The future of stem cell research offers potential treatments and cures for over 70 illnesses and diseases and will eventually be a major contributor to medical treatments and protocols in the future.
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Iz matičnih je stanica, nakon desetak godina istraživanja, uspješno uzgojen pravi funkcionalni mišić. Otkriće je to koje bi uvelike moglo promijeniti budućnost medicine i doprinjeti liječenju bolesti mišića i ostalih infekcija ili upalnih bolesti, naročito onih rijetkih, kao i za razvoj lijekaza genetske i stanične mišićne bolesti Najnovija studija koju su proveli istraživači sa Sveučilišta Duke posebna je po tome što znanstvenici nisu krenuli od mišićnih stanica zdravog mišića već od stanica izuzetih iz ne-mišićnih tkiva, poput kože i krvi, koje su potom reprogramirali kako bi se one vratile u prvobitno stanje, stanje prije nego dobiju ulogu izgradnje određenog tkiva, te ih usmjerili da počnu razvijati mišićno tkivo. Ovo otkriće pomoći će u razumjevanju i liječenju mišićnih bolesti uzrokovanih mutacijama na genima, a uskoro će biti moguće uzgojiti nove mišićne stanice kod pacijenta kojem iste propadaju što je velika novost na području liječenja staničnih oboljenja. Matične stanice natjerali da počnu kreirati mišić Istraživači su matičnim krvnim stanicama, odnosno pluripotentnim stanicama koštane srži, kada su dovoljno narasle, dodali molekulu Pax7, čarobnu molekulu koja kreira sam kostur mišića, a koja je stanicama sugerirala da se moraju početi razvijati u mišić. Stanice su se nastavile razvijati te su uskoro postajale sve sličnije stanicama mišića kod odraslih. “Činjenica da iz pluripotentnih matičnih stanica koje nisu mišićne stanice možemo razviti sve postojeće stanice u našem tijelu jednostavno je nevjerojatna. Te nam matične stanice omogućuju rast neograničenog broja miogenih stanica, odnosno progenitorskih stanica”, rekao je Nenad Bursac, profesor biomedicinskog inženjerstva na Sveučilištu Duke za Daily Mail, pojašnjavajući veličinu ovog otkrića. Biomedicinski su inženjeri zatim implantirali nova odrasla mišićna vlakna u odrasle miševe te se ustanovilo da ti umjetno uzgojeni mišići normalno funkcioniranju u živom tijelu. Tri tjedna od aplikacije mišića u miševe, ta su se vlakna u potpunosti integrirala u postojeće tkivo. Velike promjene u liječenju teških bolesti Bursac napominje kako je njihovom otkriću uvelike doprinjela 3D matrica uz pomoću koje su se stanice brže razvijale. Dodaje i kako će napokon moći liječiti pacijente, naročito djecu kojima atrofiraju mišići, a iz kojih do sada, zbog velikih oštećenja, nisu mogli izvaditi uzorke iz kojih bi potom pokušali obnoviti tkivo. Dodaje i kako je prošlo desetak godina od kada su znanstvenici u laboratoriju prvi put uspješno izdvojili matične stanice iz mišića, desetak godina eksperimentiranja i velik broj neuspješnih pokušaja stvaranja živog tkiva iz stanica koje nisu nastale iz mišića da bi napokon stvorili pravi, funkcionalni, ljudski mišić. Matične stanice osnovni su tip stanica koje imaju mogućnost promjene u druge specijalizirane stanice. Taj se proces naziva diferencijacija. Matične su stanice one koje grade embrij, a uz njihovu se pomoć plod zapravo i razvija te nastaju milijuni različitih vrsta stanica koje nastaju prije rođenja. Kod odraslih, matične stanice služe za oporavak, odnosno popravak štete nastale raznim bolestima ili starenjem. Brojna su istraživanja pokazala kako se matične stanice mogu koristiti za rast gotovo bilo koje vrste stanica.