Banking on stem cells
YOUR HEALTH
--------------------------------------------------------------------------------
DR GITA MATHAI
Actress Lisa Ray underwent stem cell therapy for multiple myeloma, a cancer of the white blood cells
Advertisements in the media advise parents to “plan and protect your children’s future and their health status”. These are not commercials for insurance plans, but private stem cell banking facilities, where, for a steep price, your baby’s umbilical cord stem cells can be preserved for future use.
Stem cells are in the news. Independent national and international laboratories are making claims and counterclaims about the “miracles” they have achieved with them. Paralysed people have been able to walk, rare degenerative nervous and muscular system diseases been reversed, and some cancers of the blood cells cured. People with terminal illnesses have also been offered hope.
Stem cells may be embryonic, adult or derived from umbilical cords. Embryonic stem cells are obtained from the extra fertilised eggs at in vitro fertilisation (IVF) centres. The use of these cells is controversial, as, theoretically, they have the potential to become human beings. They are the “spare babies” belonging to a particular IVF couple. When supplied to a stem cell research facility, they are grown in a nutrient broth in a culture dish and used for research or treatment.
Adult stem cells are found in bone marrow. These are harvested from the bone marrow of living donors. It’s a surgical procedure done under anaesthesia with some post-operative discomfort. The cells are capable of eventually forming either various types of blood cells or stromal cells from which cartilage and fat tissues arise.
Haematologists treat a variety of hereditary blood disorders and some of the blood cancers with either autologous (the person’s own) stem cells or compatible donor cells from bone marrow transplants. This technology has been used for the last 30 years. Bone marrow transplants are life saving for people with certain blood cancers. They can also be used for serious blood disorders such as aplastic anaemia. They can also help boost the immune system if it is impaired because of an inherited genetic defect or destroyed by cancer.
Umbilical cords are a rich and non-controversial source of stem cells. Cord blood has a greater ability to generate new blood cells than does bone marrow. Also, smaller quantities of cord blood cells are needed for successful transplantation. These cords are normally discarded along with the placenta from labour wards all over the world.
At present, in India, patients who require stem cell treatment or a bone marrow transplant have to search for a relative who is an appropriate tissue match. Sometimes even close first-degree relatives like a parent or sibling are not compatible. India does not as yet have a centralised national bone marrow registry to match recipients and donors.
Some foresighted countries with efficient national health schemes like the United Kingdom and Brazil do have public cord blood banks. Blood is screened for infective agents, documented in a registry and stored. The chances of finding compatible stem cells are high because of the large volumes stored.
India has private cord blood banks which store blood only for the use of that particular child for a period of 21 years. It may be a cost effective option for parents who have a family history of certain genetic diseases, such as severe hereditary anaemias, immune disorders or certain cancers. Even then, the chance that the blood can be used for that particular child is only 1 in 2,000. In families with no such risk factors, there is only about a 1-in-20,000 chance of the child ever needing a stem cell transplantation. Also, even if the child does require a stem cell transplant, it is unlikely that his or her own cord blood would be the desired source of stem cells. The same chromosomal or genetic defect causing the leukaemia, any other cancer or metabolic disorder, is likely to be present in the child’s stem cell line. There is no proof that a transplant using the child’s own stem cells is effective or even safe, especially in cases of childhood cancers.
Indians have a very diverse genetic make-up. The large-scale collection and storage of cord blood in public banks will be very useful. It can be used for matched unrelated recipients who urgently need blood cell transplants.
Stem cells are probably the future of medicine and the human race. They are multifaceted and have the potential to develop into different cell types. They can theoretically keep dividing as long as the person is alive. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another specialised cell like a muscle cell, red blood cell, or brain cell. This means stem cells can be infused as a sort of emergency repair mechanism to replenish damaged tissues.
Perhaps disease, aging, cancer and even death can be controlled and conquered. And living healthily forever may become a reality.
Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in
Wednesday, July 21, 2010
Tuesday, July 13, 2010
fat children
Catch them early
Your Health
--------------------------------------------------------------------------------
DR GITA MATHAI
When I was a medical student (so long back that it was actually in the last century), two of the cases placed before us as “spotters” (look and diagnose, don’t touch or question) in an examination were children with kwashiorkor (lethargic and disproportionately swollen with fluid) and marasmus (wizened, wasted and looking like a wise elder). Both were common conditions, the result of malnutrition.
Such diseases are rare today. In fact, now doctors have to spot diagnose children at the opposite end of the spectrum. About 20 per cent of children (some less than a year old) and teenagers in India can be defined as overweight, obese or morbidly obese. Their weights exceed that expected for their heights by 20 per cent, 50 per cent, and even 80-100 per cent. The BMI (body mass index, calculated as weight divided by height in meter squared) which should be 23 is often well above 30. Many of these children maintain their obese status into adult life.
In addition to having a paunch, big hips, knock knees and a double chin, such children have a peculiar velvety black discolouration of the skin — called acanthosis nigricans — on the nape of the neck. No amount of scrubbing will remove it, nor talcum powder conceal it. It is a marker for obesity that is likely to progress in diabetes.
This unhealthy state of over nutrition starts in infancy. Babies are breast fed for less than a year and weaned early. They are often force fed high energy, ready-to-eat carbohydrate substitutes instead of healthy, home cooked weaning foods. Older children gorge on unhealthy packaged snacks that often serve as a substitute for meals.
The children also have limited outdoor activity. Schools do not encourage physical training or games, as academics takes precedence over sports. In the evenings, tuition, homework and television usurp their time. Many parents do not have the time, inclination or space to take the children out.
Energy intake soon overtakes energy expenditure. In children, the waistline expands and fat is deposited in the abdominal regions. A paunch develops and pushes up the stomach and other abdominal contents against the diaphragm (a muscle that separates the abdomen from the chest). The chest is unable to expand fully and breathing becomes shallow, noisy and inefficient. Infections are frequent.
The excess fat is also deposited in muscles and liver tissue. The fat makes the body resistant to the actions of its own insulin. Even young children develop relative “insulin resistance”. Glucose intolerance and hypertriglyceridemia begin to develop in them. Fat gets deposited in the blood vessels. And this can cause the blood pressure to rise and result in premature coronary artery disease.
Adolescent obesity causes hormonal imbalances. In obese girls, androgens are present in excess. They develop unsightly facial hair and menstrual irregularities. This may result in PCOS (polycystic ovarian syndrome). In men, estrogen levels rise and gynacomastia develops. Eventually, these obese adolescents become subfertile adults. Pregnancy occurs only after expensive and frustrating treatment.
Obese children are also prone to numerous orthopedic problems. They may develop bowlegs. The ends of the growing bones may slip causing deformities. All this results in the early onset of arthritis.
Moreover, children are psychologically affected by their obesity. They are often the brunt of jokes. They are often excluded from sports and cultural events.
Quite often, the overweight children appear to have a familial obesity. This correlation is likely to be due to the environment with excessive food intake, limited exercise and almost compulsive television viewing. In these children, the obesity is not genetic but a result of the upbringing.
Boys (not girls) who are obese in childhood and adolescence are at risk for sudden death from coronary artery disease (CAD) as adults. They are also at increased risk for gout and colorectal cancer. This risk remains constant even if they manage to lose weight as adults. Girls who are obese become women at high risk for arthritis.
Television viewing should be restricted to a minimum. If the parents watch television for many hours every day, children too get hooked on to it. It is better to enroll them in coaching classes for activities like cricket, swimming, tennis, football or basketball. The Sports Authority of India conducts camps during summer vacations. Children who attend these camps should be encouraged to maintain the momentum even after school re-opens. Daily running or jogging for 20-40 minutes will help them keep up their stamina and maintain weight till the next round of coaching starts.
As parents and elders, we have to keep our children fit and not fat.
Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in
Your Health
--------------------------------------------------------------------------------
DR GITA MATHAI
When I was a medical student (so long back that it was actually in the last century), two of the cases placed before us as “spotters” (look and diagnose, don’t touch or question) in an examination were children with kwashiorkor (lethargic and disproportionately swollen with fluid) and marasmus (wizened, wasted and looking like a wise elder). Both were common conditions, the result of malnutrition.
Such diseases are rare today. In fact, now doctors have to spot diagnose children at the opposite end of the spectrum. About 20 per cent of children (some less than a year old) and teenagers in India can be defined as overweight, obese or morbidly obese. Their weights exceed that expected for their heights by 20 per cent, 50 per cent, and even 80-100 per cent. The BMI (body mass index, calculated as weight divided by height in meter squared) which should be 23 is often well above 30. Many of these children maintain their obese status into adult life.
In addition to having a paunch, big hips, knock knees and a double chin, such children have a peculiar velvety black discolouration of the skin — called acanthosis nigricans — on the nape of the neck. No amount of scrubbing will remove it, nor talcum powder conceal it. It is a marker for obesity that is likely to progress in diabetes.
This unhealthy state of over nutrition starts in infancy. Babies are breast fed for less than a year and weaned early. They are often force fed high energy, ready-to-eat carbohydrate substitutes instead of healthy, home cooked weaning foods. Older children gorge on unhealthy packaged snacks that often serve as a substitute for meals.
The children also have limited outdoor activity. Schools do not encourage physical training or games, as academics takes precedence over sports. In the evenings, tuition, homework and television usurp their time. Many parents do not have the time, inclination or space to take the children out.
Energy intake soon overtakes energy expenditure. In children, the waistline expands and fat is deposited in the abdominal regions. A paunch develops and pushes up the stomach and other abdominal contents against the diaphragm (a muscle that separates the abdomen from the chest). The chest is unable to expand fully and breathing becomes shallow, noisy and inefficient. Infections are frequent.
The excess fat is also deposited in muscles and liver tissue. The fat makes the body resistant to the actions of its own insulin. Even young children develop relative “insulin resistance”. Glucose intolerance and hypertriglyceridemia begin to develop in them. Fat gets deposited in the blood vessels. And this can cause the blood pressure to rise and result in premature coronary artery disease.
Adolescent obesity causes hormonal imbalances. In obese girls, androgens are present in excess. They develop unsightly facial hair and menstrual irregularities. This may result in PCOS (polycystic ovarian syndrome). In men, estrogen levels rise and gynacomastia develops. Eventually, these obese adolescents become subfertile adults. Pregnancy occurs only after expensive and frustrating treatment.
Obese children are also prone to numerous orthopedic problems. They may develop bowlegs. The ends of the growing bones may slip causing deformities. All this results in the early onset of arthritis.
Moreover, children are psychologically affected by their obesity. They are often the brunt of jokes. They are often excluded from sports and cultural events.
Quite often, the overweight children appear to have a familial obesity. This correlation is likely to be due to the environment with excessive food intake, limited exercise and almost compulsive television viewing. In these children, the obesity is not genetic but a result of the upbringing.
Boys (not girls) who are obese in childhood and adolescence are at risk for sudden death from coronary artery disease (CAD) as adults. They are also at increased risk for gout and colorectal cancer. This risk remains constant even if they manage to lose weight as adults. Girls who are obese become women at high risk for arthritis.
Television viewing should be restricted to a minimum. If the parents watch television for many hours every day, children too get hooked on to it. It is better to enroll them in coaching classes for activities like cricket, swimming, tennis, football or basketball. The Sports Authority of India conducts camps during summer vacations. Children who attend these camps should be encouraged to maintain the momentum even after school re-opens. Daily running or jogging for 20-40 minutes will help them keep up their stamina and maintain weight till the next round of coaching starts.
As parents and elders, we have to keep our children fit and not fat.
Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in
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