Tag Archives: Embryonic stem cell

Sperm Stems Sugar

Scientists have developed a novel cure for diabetes by which male patients can grow insulin-producing cells from their own testes.

Stem cells hatched from human testes may offer a cure for diabetes in the near future. A team of US researchers, including a young Indian American student, has shown that men suffering from Type-1 diabetes may be able to grow their insulin-producing cells from their testicular tissue.

The scientists, led by G. Ian Gallicano of the Georgetown University Medical Center (GUMC) in the US, have found that when these bio-engineered cells are grafted into diabetic mice, they function quite like beta-islet cells, the insulin-secreting cells normally found in the pancreas.

By decreasing the animals’ blood glucose levels, the human derived islet cells demonstrated their potential to counter diabetic hyperglycemia in humans, Gallicano told scientists at an annual meeting of the American Society of Cell Biology (ASCB) in Philadelphia yesterday.

Anirudh Saraswathula, an undergraduate student at Duke University, is a co-author of the work. Under a mentoring programme, Saraswathula — who was a student at the Thomas Jefferson High School for Science and Technology in Alexandria — worked in Gallicano’s lab last year. His contribution to the work won Saraswathula — whose parents hail from Hyderabad — several prizes at national level innovation competitions in the US earlier this year.

The current work draws from an earlier breakthrough by GUMC researchers, including Gallicano. The scientists had shown that spermatogonial stem cells (SSCs) — that produce sperm — can be converted back into pluripotent embryonic-like stem cells that are capable of morphing into any cell type that a body needs, from brain neurons to pancreatic tissue. Embryonic stem cells — as the name suggests — are derived from human embryos. Their use in clinical application is mired in ethical issues.

“No stem cells, adult or embryonic, have been yet induced to secrete enough insulin to cure diabetes in humans, but we know SSCs have the potential to do what we want them to, and we know how to improve their yield,” Gallicano said in a release issued by the ASCB.

This could work in certain types of Type-2 diabetes as well, particularly in those patients whose beta cells are shut down. “Actually our hope is for it to serve as a cure, not just a treatment. Previous attempts at curing or treating diabetes have not quite panned out,” Gallicano told KnowHow.

Despite the rising tide of diabetes patients and dire predictions of worse to come, diabetes treatment has advanced little for decades beyond blood testing and insulin replacement. The only radically new approach to Type-I diabetes in recent years has been the Edmonton Protocol, named after the Canadian city where the technique was standardised, for transplanting insulin-producing beta-islet cells from deceased donors into the pancreas of diabetic patients who can no longer survive on insulin injections. Islet cell transplantation is plagued by problems of donor shortage and death of these cells in the body because of immune-mediated rejection.

Researchers have also cured diabetes in mice using induced pluripotent stem (IPS) cells — adult stem cells that have been reprogrammed with other genes to behave like their embryonic counterparts. The technique, however, has its downside because it can give rise to tumours since the procedure requires the use of cancer genes.

However, to date, numerous barriers surround and prevent stem cell therapies from treating diabetes. With respect to embryonic stem cells, immune rejection, risk of teratoma (tumour) formation, and ethical dilemmas remain at the forefront of their delay in clinical application. Conventional adult stem cells have not lived up to their billing either as they are difficult to generate in the quantities necessary, and they, too, can face immune rejection, explains Gallicano.

As a result, the search has gone on to find a stem / progenitor cell that is deemed “suitable” by the Food and Drug Administration for use in the clinic. “In light of this, we believe our preliminary data using SSCs show significant promise in addressing these critical barriers. Our cells do not need external genes to become pluripotent. There are no ethical dilemmas we are aware of. Our cells do form teratomas — but it takes 10 times more cells to do so when compared to IPS or ES cells, and they secrete very high levels of insulin once we differentiate them,” says Gallicano. For the present experiment, the scientists used SSCs harvested from deceased human organ donors.

Another advantage of the procedure, according to Gallicano, is that there is no chance of immune rejection, a major bottleneck of most organ transplants. That’s because these beta-islet cells are obtained from the patient’s own testes.

“If pluripotent stem cells could be derived from a patient’s own testes, problems of organ shortage and immune rejection could be bypassed. This research holds great promise for Type-1 diabetes patients,” says Anoop Misra, head of the department of diabetes, obesity and metabolic diseases at Fortis Hospital, New Delhi.

The scientists are hopeful that a similar methodology may yield a potential cure for female diabetics as well. “The fundamental approach of transforming male gametes (male sperm cells) into pluripotent stem cells might be applicable to the female counterpart — that is, oocytes,” Gallicano observes.

Source: The Telegraph ( Kolkata, India)

Wisdom Teeth Contain Reservoir of Tissue for Creation of Stem Cells

For most people, wisdom teeth are not much more than an annoyance that eventually needs to be removed. However, a new study shows that wisdom teeth contain a valuable reservoir of tissue for the creation of stem cells; thus, everyone might be carrying around his or her own personal stem-cell repository should he or she ever need some

Groundbreaking research back in 2006 revealed that inducing the activity of four genes in adult cells could “reprogram” them back into a stem-cell-like state; biologically, these induced-pluripotent stem cells are virtually identical to embryonic stem cells, opening up a new potential avenue for stem-cell therapy whereby patients could be treated with their own stem cells.

However, despite their promise, making iPS cells is not easy; the reprogramming efficiencies are very low and vary among the cells that can be used for iPS generation and thus require good amount of “starter” cells – which might involve difficult extraction from body tissue (unfortunately skin cells, the easiest to acquire, show very low reprogramming efficiency).

Now, a team of scientists at Japan’s National Institute of Advanced Industrial Science and Technology may have found an ideal source: third molars, commonly known as wisdom teeth.

The soft pulp inside of teeth contains a population of cells known as mesenchymal stromal cells that are similar to cells found in bone marrow, a common stem-cell source. However, unlike bone marrow, tooth pulp is more easily obtained, especially in wisdom teeth, which most individuals have removed anyway.

The researchers, led by Hajime Ohgushi, collected tooth samples from three donors and managed to generate a series of iPS cell lines following the similar procedure of activating three key genes (however, in another beneficial change they did not have activate the c-MYC gene which might lead the cells to become cancerous).

The different cell lines displayed varying degrees of robustness but in some cases proliferated quite well, up to 100 times more efficiently than typical skin-cell-derived iPS cells. The molar-derived cells also could differentiate into many other cell types including beating cardiomyocytes (see an attached movie), as expected.

The presence of a supply of MSCs in wisdom teeth could have meaningful therapeutic ramifications. As noted by the researchers and others, wisdom tooth extraction is a common medical procedure in developed nations and, thus, creates a perfect opportunity to remove biological material in a sterilized setting; the teeth subsequently can be frozen and stored for many years until needed. In the meantime, that also provides time for researchers to better understand the details of iPS creation to further increase the efficiency for clinical use.

You may click to see :Extracted wisdom teeth could be new stem cell reservoirs

World News on Wisdom teeth & new stem cell

Source :Elements4Health

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Your Gums May Save Your Life


Stem cells now have an easy and superior source — gum tissue.As per latest lab report.

……………....CLICK  & SEE

The history of modern medicine has rarely witnessed anything as controversial as stem cell therapy. Exponents swear by its potential to change the face of treatment and alleviate suffering. Taking advantage of this, unscrupulous medicos across the world have used the therapy to make a quick buck. Their claims — which are, of course, unsubstantiated — have caused further damage, almost discrediting this treatment method that explores the possibility of introducing new cells into damaged tissues to cure a disease or an injury.

As the name suggests, stem cells are capable of growing into various types of cells found in the human body. They can help form bones, muscles and even heart and brain cells. Medical scientists hope they can offer an answer to many diseases that have been so far regarded as incurable.

An enormous amount of research is required to take the therapy to a standard where it can be put to use extensively. However, there is a problem — providing more and more researchers easy access to stem cells is a daunting task.

A team of Indian researchers has found a better source for at least one important type of stem cells. Scientists led by Mohan Wani at the National Centre for Cell Science (NCCS), Pune, have shown that mesenchymal stem cells (MSCs) — which have the potential to regenerate muscles, bones and even nerve cells — can be extracted from human gum tissue.

Stem cells are of different types. Some are pluripotent — that is, they can be grown into all types of cells found in the human body. Human embryos are a good source of pluripotent stem cells. Most of the ethical issues relating to stem cell research are in connection with these stem cells.

The MSCs, on the other hand, are multipotent — that is, they can grow into only certain types of cells. Scientists have shown in the lab that MSCs can be used to regenerate bones, cartilage and muscles, but this is yet to become a line of treatment.

Studies in the past have shown that MSCs are present in virtually all organs and tissues in the body. But they are normally harvested from bone marrow, the soft tissue inside the bones. One of the reasons, perhaps, is that the technique to extract bone marrow has been around for more than three decades. Bone marrow transplant has been a popular method of treating many blood disorders, including thalassaemia and certain blood cancers.

However, the process of extracting bone marrow cells is painful, particularly for the elderly. “Harvesting bone marrow from the iliac crest of the pelvic bone is a painful course. Moreover, you need to extract the tissue in a large quantity as the number of MSCs in it is low,” says Wani.

Gum tissue, on the other hand, not only contains more stem cells but also of a more homogenous type. Bone marrow contains more than one type of stem cell. Besides, the process of harvesting stem cells from gum tissue is easy and leaves no scar, says Wani.
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The NCCS work, which appeared in the latest issue of the journal Biochemical and Biophysical Research Communications , says that gum tissue can be a superior source of stem cells for several reasons. The yield of MSCs from bone marrow ranges from 0.001 to 0.01 per cent. In case of gum tissue, “we are expecting a four to six-fold increase,” says Wani.

The study looks interesting, says Maneesha Inamdar, a researcher at the Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, who works in the area of stem cells. Oral cells are more accessible and hence could be a better alternative to bone marrow, she observes.

Another expert from Christian Medical College, Vellore, however, is not so hopeful. “I do not anticipate people lining up to have their gingival (gum) tissue biopsied to produce these cells, nor do I see any dramatic impact of the use these cells in the clinic in the near future,” says the scientist, who prefers to remain anonymous.

There are other benefits of stem cells extracted from gum tissue, says Wani. The scientists, who grew many generations of the cells in the lab, found that they could hold their inherent properties for much longer than those derived from bone marrow. “These cells exhibited no abnormalities and are hence safe for clinical applications,” Wani told KnowHow.

As the next step, the Pune researchers plan to use to the stem cells derived from gum tissue to regenerate different types of human tissues.

So take care of your gums, for they will take care of you one day, if needed.

Massaging of Gum with a finger and rinsing the mouth at least two to three times daily after  eating, is the easiest way to keep the gum muscles strong &  healthy.

You may click to see:->Home Treatments for Gum Disease

Source : The Telegraph (Kolkata,India)

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Amniocentesis

Definition:
Amniocentesis (also referred to as amniotic fluid test or AFT), is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, in which a small amount of amniotic fluid, which contains fetal tissues, is extracted from the amnion or amniotic sac surrounding a developing fetus, and the fetal DNA is examined for genetic abnormalities
Tests of fetal cells found in this fluid can reveal the presence of Down syndrome or other chromosome problems in the baby. Amniocentesis can also show whether the lungs of the baby are mature enough to allow it to survive if it were elivered right away.

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Amniocentesis is often recommended for pregnant women over age 35, women who have an abnormal “triple screen” blood test during pregnancy, or women who have (or whose husbands have) a family history of certain diseases or birth defects.

How do you prepare for the test?

You should have a serious discussion with your obstetrician regarding whether to have amniocentesis. Amniocentesis may be done anytime between the 14th and 20th weeks of pregnancy to test for fetal abnormalities. To check on fetal lung development, the test may be done late in the third trimester.

Tell your doctor ahead of time if you have ever had an allergic reaction to lidocaine or the numbing medicine used at the dentist’s office.

Just before the test, you should empty your bladder.

How the test is performed ?
Before the actual procedure, a local anesthetic is sometimes given to relieve the pain when inserting the needle used to withdraw the fluid. A needle is usually inserted through the mother’s abdominal wall through the wall of the uterus into the amniotic sac. With the aid of ultrasound-guidance, a physician aims towards an area of the sac that is away from the fetus and extracts approximately 20ml of amniotic fluid for testing. The puncture heals, and the amniotic sac replenishes the liquid over a day or so. After the amniotic fluid is extracted, the fetal cells are separated from it. The cells are grown in a culture medium, then fixed and stained. Under a microscope the chromosomes are examined for abnormalities. The most common abnormalities detected are Down syndrome, Edward syndrome [Trisomy 18] and Turner syndrome [Monosomy X]. Amniocentesis is most safely performed after the 14th-16th week of pregnancy, does not need to be done before then due to risk it can to to the babys limbs. Usually genetic counseling is offered prior to amniocentesis.

What happens when the test is performed?
You wear a hospital gown and lie on your back on a table. An ultrasound is done to show the location of the fetus and placenta. Your lower abdomen is cleaned with an antibacterial soap. In some cases, the doctor uses a small needle to inject a numbing medicine just under the skin, so you do not feel the amniocentesis sampling needle later. (Because the sampling needle does not cause much more stinging than the numbing medicine itself, not every doctor includes this step.)

The hollow sampling needle is several inches long and is inserted through the skin and abdominal muscle and then through the wall of the uterus. A syringe attached to the needle is used to collect a sample of fluid.

The baby’s heart tones and the mother’s blood pressure and heart rate are checked at the beginning and end of the procedure. The whole procedure takes close to 30 minutes.

Risk Factors:
Although the procedure is routine, possible complications include infection of the amniotic sac from the needle, and failure of the puncture to heal properly, which can result in leakage or infection. Serious complications can result in miscarriage. Other possible complications include preterm labor and delivery, respiratory distress, postural deformities, fetal trauma and alloimmunisation (rhesus disease). Studies from the 1970s originally estimated the risk of amniocentesis-related miscarriage at around 1 in 200 (0.5%). A more recent study (2006) has indicated this may actually be much lower, perhaps as low as 1 in 1,600 (0.06%). In contrast, the risk of miscarriage from chorionic villus sampling (CVS) is believed to be approximately 1 in 100, although CVS may be done up to four weeks earlier, and may be preferable if the possibility of genetic defects is thought to be higher

Most women experience a few hours of mild pelvic cramping, and a few will have slight vaginal bleeding. About 1 in 100 women will have a temporary leak of amniotic fluid through the vagina; this usually causes no problem.

There is a small risk of miscarriage associated with amniocentesis; this occurs in about 1 in every 200 to 400 cases, depending in part on the timing of the test and the experience level of the physician performing it. Other risks (such as infection or injury to the fetus that does not cause miscarriage) are extremely rare.

What must you do after the test is over?
If the test confirms that you are Rh incompatible with the fetus, you will need to receive an injection of a medicine called Rh immune globulin (Rhogam) to protect the baby from complications.

Let your doctor know immediately if you are having any vaginal bleeding, fluid leakage, or strong abdominal pain.

Time to know the result:
Chromosome analysis of the fluid sample takes two weeks or more. The results of some tests may be available sooner.

Amniocentesis and stem cells:
Recent studies discovered that in amniotic fluid there are a lot of multipotent stem cell, mesenchymal, hematopoietic, neural,epithelial and endothelial stem cell[1][2][3]. Amniotic stem cells don’t have ethical problem. In fact, in harvesting embryonic stem cells, a human embryo is destroyed, and so it’s considered it immoral. Another potential benefit of using amniotic stem cells over those obtained from embryos is that they side-step ethical concerns among pro-life activists by obtaining pluripotent lines of undifferentiated cells without harm to a fetus or destruction of an embryo.

Artificial heart valves, working tracheas, as well as muscle, fat, bone, heart, neural and liver cells have all been engineered through use of amniotic stem cells [4]. Tissues obtained from amniotic cell lines show enormous promise for patients suffering from congenital diseases/malformations of the heart, liver, lungs, kidneys, and cerebral tissue

You may click to see:->HOW TO – Isolate amniotic stem cells from a placenta, at home

Resources:
https://www.health.harvard.edu/fhg/diagnostics/amniosentesis.shtml
http://en.wikipedia.org/wiki/Amniocentesis

http://healthlibrary.epnet.com/GetContent.aspx?token=7e9094f4-c284-4b3a-8f7c-867fd12b36ee&chunkiid=14762

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A Possible Cure for Diabetes Ignored by Big Pharma

Twelve years ago, Professor Irving Weissman discovered a treatment that could have saved the lives of thousands of women with advanced breast cancer. Pharmaceutical companies weren’t interested in developing the therapy at the time.

Though interest in his methods are finally being ignited, Weissman regrets the wasted time. In a set of lectures, Weissman repeatedly expressed frustration that while many of his discoveries in the field of stem cell research seemed to hold remarkable potential for life-saving treatments, commercial or regulatory hurdles have prevented his scientific findings from benefiting patients.

One example is Weissman’s research on type I diabetes, in which he demonstrated the ability to fully cure type I diabetes in mice using stem cells. But even though his experiments avoided political controversy by using adult stem cells, which do not come from embryos, Weissman ran into a road block when pharmaceutical companies refused to sponsor clinical trials.

Weissman believes that the pharmaceutical companies put profit over principle, preferring to keep diabetes sufferers dependent on costly insulin than to cure them once and for all.

Sources: Columbia Spectator January 23, 2009

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