why are most differentiated cells poorly suited for transplantation to regenerate a tissue?
139576
Although differentiated cells have the entire genome of the organism (yes, there are exceptions, but don't worry about that now), many parts of it are inactived, and this inactivation is hard to undo. Thus, a muscle cell has the genes for a neuron, but it can't use them, and we can't figure out how to undo this programing.\n\nAs for HIV, it is a virus, and it just uses our genes for lipid synthesis.
765492
A stem cell is essentially a cell with potential; it hasn’t yet become a specific, ‘useful’ cell. Stem cells are capable of becoming a variety of ‘useful’ cells. For example, a blood stem cell may become any type of blood cell, such as red or white. The basis of stem cell use in medicine is to manipulate their growth into tissues which people have lost through injury or disease, such as loss of certain brain cells in Parkinson’s disease, and thereby treat diseases previously considered incurable.\n\nTHERE ARE INFACT TWO TYPES OF STEM CELL undergoing medical research: Embryonic Stem Cells (ESCs) and Adult Stem Cells (ASCs). \n\nASCs are taken from a human adult, and usually either transplanted to another part of the body, or artificially encouraged to grow to greater numbers. ESCs are taken from human embryos which have been created artificially. Under the right conditions, these cells can then be grown in a lab, and if given the appropriate chemical signals, can be manipulated to become virtually any type of cell imaginable. In either case the aim is to replace tissues lost through disease.\n\nThose opposed to the use of ESCs strongly advocate the use of ASCs. However, many scientists believe that ASCs are ultimately less useful medically, as they cannot replace all types of cells. They exist in very small amounts and are therefore hard to find, and in extremely limited supply if wanted for transplantation on a large scale. They are also difficult to grow in culture. By contrast, ESCs are easy to isolate, grow and manipulate, and have a greater variety of uses. Thus, they are favoured by scientists as a medical tool. As ASCs come directly from the adult patient, there is essentially no controversy, as there are no life-issues at stake. It is the use of ESCs which\nis the cause of the debate, as it involves artificially creating a human embryo, harvesting the cells and then destroying the embryo. The moral objections to this revolve around a fundamental question - when does a group of cells constitute a human life? Put simply, are we playing God, and it is morally acceptable for us to do so? There has been no definitive conclusion, and the argument continues.\n\nThe variety of diseases which can potentially be treated with ESCs is huge, ranging from degenerative disorders such as Parkinson’s disease, to diabetes, and even cancer. If successful, it could be the greatest reliever of human suffering since the introduction of antibiotics. However,\nthe moral arguments surrounding their use do not look set to be resolved any time soon. Regardless, the immense potential medical benefits cannot be ignored, and so research continues amidst the controversy.
1003804
about 60-75% everybody's body protein is basically the same DNA but because each of us have subtle diffrences the Proteins and Amino Acids combine differently. Sometimes the transplants are not always successful for that reason. It is not easy to find a 100%match because like snowflakes everybody is different. Hopefully if people would stop being so closed-minded , religiously over zealous, and ignorant about STEM CELL RESEARCH maybe we can solve a lot more problems like this one. Until then check out this book:\n\n                    THE EYE CARE REVOLUTION By Dr. Robert Abel Jr.
805439
I'm sorry, but some of the answers on here are utterly wrong in terms of science - there is a very big difference between stem cells from embryos, and stem cells from places like bone marrow.\n\nTHERE ARE INFACT TWO TYPES OF STEM CELL undergoing medical research: Embryonic Stem Cells (ESCs) and Adult Stem Cells (ASCs). \n\nASCs are taken from a human adult (eg from bone marrow), and usually either transplanted to another part of the body, or artificially encouraged to grow to greater numbers. ESCs are taken from human embryos which have been created artificially. Under the right conditions, these cells can then be grown in a lab, and if given the appropriate chemical signals, can be manipulated to become virtually any type of cell imaginable. In either case the aim is to replace tissues lost through disease.\n\nThose opposed to the use of ESCs strongly advocate the use of ASCs. However, many scientists believe that ASCs are ultimately less useful medically, as they cannot replace all types of cells. Blood stem cells can only become blood cells. They exist in very small amounts and are therefore hard to find, and in extremely limited supply if wanted for transplantation on a large scale. They are also difficult to grow in culture. By contrast, ESCs are easy to isolate, grow and manipulate, and have a greater variety of uses. Thus, they are favoured by scientists as a medical tool. \n\nAs ASCs come directly from the adult patient, there is essentially no controversy, as there are no life-issues at stake. It is the use of ESCs which is the cause of the debate, as it involves artificially creating a human embryo, harvesting the cells and then destroying the embryo. The moral objections to this revolve around a fundamental question - when does a group of cells constitute a human life? Put simply, are we playing God, and it is morally acceptable for us to do so? There has been no definitive conclusion, and the argument continues.\n\nThe variety of diseases which can potentially be treated with ESCs is huge, ranging from degenerative disorders such as Parkinson’s disease, and even cancer. If successful, it could be the greatest reliever of human suffering since the introduction of antibiotics. To give some examples: A univeristy research team in America is close to creating a CURE to diabetes. Stem cells can be encouraged to produce insulin. These can then be transplanted into the patient, and they will never have to inject themselves with insulin again!! Another research team, in the UK, has managed to get stem cells to grow into liver tissue. This tissue can be used to test new drugs, so removing some of the need for animal testing - something I think most people would like to see! In the future, we will be able to grow whole organs for people!!\n\nI would like to point out that aborted babies are NOT used for stem cell research. The embryos are created in the lab, and growth is stopped when it reaches 8 cells. This way, all the cells are still stem cells, and so useful. Babies which have been aborted are far too large and devoloped to be useful in this way.\n\nHowever, the moral arguments surrounding their use do not look set to be resolved any time soon. Regardless, the immense potential medical benefits cannot be ignored. It is my view that the research should be allowed to continue, as it could help people in so many ways. Those who are opposed do not have to make use of the treatments once they become available, like Jehova's Wittnesses, who refuse blood transfusions because it against their beliefs. But I belive in giving people the choice.
756341
Stem cells have the ability to differentiate into many different types of cells, they are called pleuripotent.  Regular cells do not have the ability to differentiate into any other kind of cell and the division of a regular cell will result in an identical and functionally similar daughter cell.  Stem cells can divide and one daughter cell may differentiate into a neuron and the other daughter cell may differentiate into a kidney cell.
753734
Replicate everyday: epithelial cells (skin, mucosa), bone marrow progenitor cells, lymphocytes (some of them)\nDo not replicate: neurons, skeletal muscle cells, neutrophilic granulocytes, any terminally differentiated cell
406196
It is tissue (i.e. cells) obtained from foetuses, often used in medical experiments.
837264
This is not possible for countless reasons.  First of all, when you say elements, the body is comprised primarily of cells, and all cells are subject to immune system monitoring, just like any invasive substance.  Now, all of the cells body express products that tell the body "this is your body, do not kill me".  Any part that does not express these products will be destroyed.  This is what makes transplants difficult.  So your idea is something that can never come to fruition.
299768
Stem cells have the potential to differentiate into any cell of the body.  This is a great potential that if we learn how to harness we may be able to create tissues and whole organs that can be used for transplantations.  Stems cells can also be used to cure diseases and repair tissues.  Complete understanding of our genetic code in the future will allow us to accomplish all of this and more, probably increasing our quality of life and lifespan.
870080
Good question.  Neurons do not regenerate, and do not divide.  This is why nerve damage is so severe (i.e. Multiple Sclerosis).  Neurons are said to be at the END of cell lineage.  There are of course exceptions, but for all intents and purposes, this is all you need to know.
137642
In theory, yes.  In practical point of fact, considering how difficult it is to find a properly matched heart (in terms of the tissue antigens, that is), it is most unlikely that anyone would have the procedure done.\n\nTechnically, it is possible.  Practically, it is infeasible.\n\nThe only exception?  Electromechanical artificial hearts (Like Jarvik's work); those are usually implanted without removal of the native tissue.
714647
Anyone who's ever had an organ transplant is "a creature made of sets of cells containing different DNA".\n\nIt's not impossible that you could graft or grow bits belonging to different animals into one single body, but it would take some advances in molecular biology to do it. You can't just snip the "genes for a head" from a lion and the "genes for a tail" from a snake, it's much more complicated than that.\n\nThat said, a mouse was grown a few years back that had a fully grown human ear on its back. It was supposed to indicate that replacement organs could be grown for people.
550150
Well , you see adult human neyron , that is barin cells have no capacity to regenrate and develop , so with paraplegia some cells have died and are no longer part of cicuit , the circuit has breaken dwon,  so when u infuse these human embryonic stem cells, these cells like embryonic cells have the capacity to divide , develop , and regenerate the circuits , this was re establishing the network which has been disturbed , reverst back to work.
1138603
Actually adult stem cells are MORE versatile than embryonic ones.  At least to date.\n\nVery little has been accomplished w/ embryonic stem cells, while much has been done w/ mature stem cells.\n\nAnd there are no ethical concerns about mature stem cells.
1060558
a.cell fusion -2 Living cells fused using synthetic medium artificially, it casues karyoplast fusion as well as cytoplast fusion, When an undifferentiated stem cell fuses with a mature differentiated cell, the resultant cell can retain the mature cell \n\nb.Tissue culture - A branch of biotechnology working using invtro cell lines in a petridish growing in 37 degree incubator with 5% Carbon dioxide.. example Hela cell lines - A cell line obtained from Henrita laks ( other exapmles like  tissues cut from kidney or other tissues and homogeneous suspension is  made  and grown in dishes to study drug targetting and for transfection.Also in plants small part of bud is cultured in a test tube with appropriate shoot inducing and rooinducing hormones to get plants with desired charecters .A biotechnology teaching college is incomplete without a tissue culture lab aslo known as cell culture lab\n\nc.Recombinent DNA - Most of the times bacterial plasmids are engineered to ligate with gene of interest using enzymes to obtain required protein ,usually used for commercial purpose and also for research purpose ( recombining DNA -a major feild also called as genetic engineering )\n\nd.Embryo transfer - 2 kinds of embryo transfers are commenly seen .One in the laboratory,it is done using mouse embryos, after embryo manipulations , to obtain transgenic animals or knock out animals or for other purposes embryos are transfered to a surrogate mother ,It is done in two ways. uterine or oviduct (depending on the stage of the embryo) , 2nd one ,in hosipitals  invitro clininc IVF therapy ,Embryos are transferred using a cappilary pipe and a syringe,through the vegina ( generally in blastocyst stage)to the mother after invitro fertilisation for those mothes who has problem in natural fertilsation and also for various other reasons ,to get disigned babies .Embryo transfers are also practicved in other animals as well .Dolly is also a gud example born after embryo transfer after somatic cell nuclear transfer \n\ne.Artificial insemination - Here sperm is placed into a female's uterus by artificial means unlike natural copulation.Semen is collected, extended, then cooled or frozen. It can be used on site or shipped to the female's location.artificial insemination were first developed for the dairy cattle industry to allow many cows to be impregnated with the sperm of a bull with traits for improved milk production.and also in other animals .In humans artificial insemination is usually part of an infertility treatment; either the woman's partner's sperm (artificial insemination by husband, AIH) or donor sperm (artificial insemination by donor, AID) can be used.\n\nf.protoplast fusion - a technique used to generate genetically modified fruits,Protoplast is nothing but cell minus cell wall , so two protoplasts are fused from two fruits after removing cell wall using generally PEG and sendiviruses to enhance fusion .Generally it causes somatic cell fusion.Protoplasts are useful in genetic manipulations because they do not have cell walls. They are ideal targets for taking up naked DNA and for fusing with protoplasts of other related species. In the related genus, Episcia, some species and selections have true yellow and red flowers. this procedure has been successfully applied  for plant regeneration from African violet protoplasts to protoplasts of Episcia cupreata Tropical Topaz .Several researchers have emphasized production of hybrids between distantly related, sexually incompatible species, not all are success stories there are more failure also .\n\ng. test tube baby - A test-tube baby is the term that refers to a \nchild that is conceived outside the woman's body.  The first \nsuccessful test-tube baby was born in England in 1978 and since then.over 20,000 test-tube babies have been born worldwide. The process is referred to as in vitro (outside the body) fertilization.Simply put, eggs are removed from the mother's ovary and inc
738424
Stem cells are primal cells that retain the ability to renew themselves through cell division and can differentiate into a wide range of specialized cell types. Research in the stem cell field grew out of findings by Canadian scientists Ernest A. McCulloch and James E. Till in the 1960s.\n\nThe two categories of stem cells include embryonic stem cells and adult stem cells and possibly a third, cord-blood-derived embryonic-like stem cells (CBEs). In a blastocyst of a developing embryo, stem cells differentiate into all of the specialised embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells. As stem cells can be readily grown and expanded via cell culture, their use in medical therapies has been proposed.\n\nlook at http://en.wikipedia.org/wiki/Stem_cell_research#Embryonic_stem_cells
1129900
Some people just need to fight something, for a lack of a better purpose in life.\n\nFoetus and stem cell research can allow to re-grow damaged/amputed organs or maybe even entire limbs.