Sunday, November 18, 2012

embriyoid body formation is used for embriyo generated in vitro situation. it is grown in vitro and in the stage of blastocyste inner cell mass isolated and it is grown in medium for providing ıts immortal division. after it is providen it is exposed to some growth factors and others respectively for obtaining differantation to which cell we want. there are more signaling factors which triggers a cell for differantiating and they are waiting for to be explored.

Sunday, November 11, 2012

degenerated pancreas beta cells.ıs it possible replace them via stem cells.recent studies show that adult stem cells can not replace them but embryonic stem cells or adult beta cells replication is thought can replace.on the other hand dediferantation of cells for example pancreatic exocrine cells to pancreatic beta cells.ıt must be known which signaling mechamisms effects them to dedifferantie.ıt is releated with molecular biology.after dediferantation what must be done ı am interest with it deeper.maybe duplication of beta cells can be triggered in vivo but how it will be done.

Saturday, October 20, 2012

what are the the caharacteristic figures of neuron? answer:the eurochromatine,spherical nucleus and the distinctive nucleolus.some times there are two nucleolus.the barr apparatus can be seen.we can't see centriole near the nucleus because the neurons do not divide. we see the centrioles at the periphere of perikaryon near the cilia.the function of cilia is not known excatly. it is known that it gets lost by the time except the neurons' have modified ciliaes rod and coni cells in the retina.the neurons have numerous mitochondrias which have spherical or flat shapes and their cristas are vertical or longitudinal.the nissl apparatus are characteristic figure of these cells and ıt is supposed that they protect neurones after travma or damaging events.ıt was seen when neurons were damaged the nissl aparatus dissolved and scattered everywhere of the some.the dendrites have the nissl apparatus,too but axons do not have for this reason it is an advantage for histologists to distinct axons from dentrites.all the neurons have only one axon but the number of dendrites can be changed.the microtubules and microfilamentes are very important for conducting organals,vesicles and metabolites.the protoplasma is syntesized in the soma and conducts to dentrites and axon.it is seen in the soma there are developet granular endoplasmic reticulum and golgi apparatus.the nissl apparatus are thought that they are consist of some granular endoplazmic retuculm cisternaes,free ribosomes and poliribosomes.these all the features of organels say that neurons are very productive cells.they syntesize protein and they are anabolic cells.

Sunday, October 14, 2012

brain and oxidative stress

Hystopatalogical alterations in brain causes oxidativa stres.Mental distress is an important result of oxidative stress and you know bipolar disorders is one of the mental disorders.recently studies indicated that lithium which treats bipolar disorders decrease oxidative stress in the brain.but this positive effects of lithium can't be seen in other organs.why?what is the mechanism for lithium which working in brain positive contrary to the other organs?
discussing liver and blood testis barrier:we know some cells have duplicated nucleus like liver or muscle cells.but some of us know the liver cells nucleus have 4n,8n.12n e.g chromosomes.we think their nucleus have 2n chromosomes(46) but that is not.you know sperm has n(23) chromosomes and that is advocated that blood testis barrier is protecting sperms from immun system cells.ıf ıt is like that wyh there isn't a system protecting hepatocytes from immun system cells and when we research we see there are fenestreated capilleries not continous capilleries between hepatic cords.the hepatocytes are close to blood for this reason ı think the purpose of blood testis barrier must be for differen cause.

Saturday, October 13, 2012

ı haven't written for a long time because ı was on holiday.ı want to give information about pancreas b cells and stem cells.(you know ı am interest in stem cell and ı want my workings to be releated with it.) diabettus mellitus type 1 is widespread dissease in the world.it is an outcome of degenerating b cells in pancreas with auto immun attack.there are many methods applied for treating.one of them is langerhans islets transplantation from cadavra's donor but it has not conclusive solution.ıt provides solution for a period longer than three years indepence of insulin.at the present time the stem cell treatment is promising.there are three ways.one of them is using embryonic stem cell or human stem cell for obtaining insulin secreting cells,the other is reprogramming somatic cells to convert b cells and the other is replication of b cells in vivo or in vitro conditions.

Thursday, September 6, 2012

ı could not write recently.two days ago ı gave a presentation about bone tissue in my school.the important point which stuck in my mind are; 1)the difference of primary and secondary bone(primary bone is irregular and secondary bone is regular. the distinctive factor is the structure. we see the second bone(compact bone and spongious bone) have a lamellar structure), 2)and it is said that osteoblasts have euchromatin nucleus ocyteocits have heterochromatine nucleus but we see in some electromicroscophic photos some ocyteocytes' have euchromatin nucleus. ı think they are the cells near the vessels carrying and getting back nutrients to and from the other ocyteocits away from the vessels.because of their much more activates they have euchromatin nucleus....tomorrow ı will go on...

Wednesday, August 29, 2012

connective tissue derives from mezoderm and mesencyme cells derived from mesoderm.the epitel tissue is avascular.melanocytes are mostly specific to our scin.(whole epitel tissue?)fibroblasts do not go mitosis and they do not dejenerate like other cells.the fibroblasts give rise to fibrocyte and also fibrocyte give rise fibroblasts but the second condition occurs when more fibroblasts are necessary.the ribozomoses in cells are syntesized in nucleolus and cytoplazm.the myofibroblasts have two characteristic feature in sequence first they syntesize collagen fibrils(actin flamanetes) and second they are smooth muscle cells.the smooth muscle cells have gap junctions and this feature is important for their contraction.stable macrophages are not phagocyte but independent macrophages are phagocyte.some macrophages are said hemosiderin-laden macrophages.we saw these macrophages in the respiratory sistem when more blooding occurs.plasma cells are like tears in the sections hemotoxilen-eosin stained and they are watched eosiophilic.in electron microscopic visualing their nucleus seen like car wheel.the nucleus has nucleolous in the center it has mrna and rrna the other hiperchromatic area near the nucleus membran has only dna.

Monday, August 27, 2012

stem cells isolated from fat using for diseases or tissue damage is accessibility and lack of rejection.the fat deriverde stem cells secrete vaso endotelhial growth factor(vegf) and other factors which can inhibit cartilage regeneration.but ıts effect can be neutralized by antibodies.

Sunday, August 26, 2012

prohibitin is a mitochondrial protein.in rats who were treated ischemia tolerance ıt was seen there was prohibitin upregulating.prohibitin reduces relesing of radical oxygen spices from mitichondria.ıt is thought that prohibitin is an endogeneus protective protein that support mitochondria's function.besides the effects of prohibitin in nerve tissue is not known exactl it is argued it protect neurons.Prohibitin reduces mitochondrial free radical production and protects brain cells from different injury modalities Ping Zhou,1,2 Liping Qian,1,2 Marilena D’Aurelio,2 Sunghee Cho,1,2,* Gang Wang,1,2 Giovanni Manfredi,2 Virginia Pickel,1,2 and Costantino Iadecola1,2

Saturday, August 25, 2012

is it a dream an organ or a pice of human body can be generated from his own blood.nearly scientific experiments support this dream.a six day old embryo can be generated from blood cells.when it is compared with other models(embriyonic stem cells,skin or hear derivered stem cells and virus deppended stem cells).possibily while you are reading this post you can ask how can a cell turn back on its one step or more before its state.ıt is like getting time to back.but it is possible and ıt appears that is reliable method than others.ıt is virus-free way to handle induced pluripotent stem cells(ips).instead of viruses plasmids are used.plasmids are cause of reverting cells to a more primitive stem cells.thus it is prevented viruses' potential impact which mutate genes or initate transforming cells' cancer
do you know when an old or damaged erytrocite went to pieces by lymphocytes ıts iron is used to participate in the structure of erytroblast or it is used by liver as bile,therefore the color of the bile dark brown colored,
An embriyonic stem cell or human bone marrow stem cell.it is said embryonic stem cells have capacity to diferantie 250 cell types.for instance pancreas cell can not be generated from bone marrow stem cells because of bone marrow stem cells can be differantied into at the very most 15 cell type.when embriyonic stem cell compared with human bone marrow stem cells current state seems like an advantage but also it has some desadvantage such as laws because the embryos are unborn child and they have right to life and also they have families.there must be obtain approvel with the family.there is another problem with embryos' dna and the human enjected stem cells whose dna.in the future there can be a huge problem because of dna mismatch.
The functon of basofiles is to migrate to connective tissue whereever they become mast cells.mast cells release heparin and histamine.histamine provides vasodilatadion of vessels which promoting immune cells migrating from vessels to tissues.heparin is an antiquagilant.

Friday, August 24, 2012

today ı watched a video about stem cells.stem cells are hopeful for injured people,handicapped people or some people whose disease can be recovered by stem cells.for instance ıf pancreas stem cells can be generated for the diabetes mellitus patients or the other disases originating from pancreas ıt provides removing these disases.
helo..today ı want to explain about me.ı am anurse and ı am 32 years old.ı am married and ı have a girl whose name is azra.for a long time ı want to have an alteration in my mind.ı am a msc student ı want to improve my english and ı want to have scientific paper.on the other hand ı want to share my ideas and suggetions and interests with people

Wednesday, August 22, 2012

sharing information

hello.ı am a new user.ı want to share something about histology and embryology.ı am Msc student in atatürk üniversity in turkey.most of the time ı will talk about articles ı read. ı will criticize ı think the most important.
ı have just read an abstract about a study to investigate correlation between brain derivered neurotropfic factor(BDNF) expression and cognitive impairment in post stroke depression (psd) rats and to explore mechanisms of the cognitive impairment process.the middle cerebral artery was occluded for establishing a focal ischemia in rats