Stem cells, which stand ready to replenish mature cells lost to wounds, diseases and everyday wear and tear, can lose their normal functions as they age. But research now shows that stem cell ageing may be reversible.

A team of Howard Hughes Medical Institute (HHMI) researchers has found that in old mice, a several-week exposure to the blood of young mice causes their bone marrow stem cells to act “young” again.

The researchers have not yet isolated the blood-borne factors that can rejuvenate old stem cells, but their results are consistent with other recent studies that show stem-cell ageing may be reversible.

The results suggest that it might one day be possible to boost the practical lifespan of stem cells, and thereby increase the body’s resistance to disease and age-related degeneration.

Amy J. Wagers, HHMI’s principal study investigator had participated in two previous studies that found that the blood of young mice appears to contain factors that could improve the repair capabilities of muscle and skin in older or diabetic mice, respectively.

In the new work, Wagers and her team decided to find out whether blood-forming (hematopoietic) stem cells in the bone marrow could also be rejuvenated.

Hematopoietic stem cells give rise to all the cells of the blood system, including immune cells and red blood cells.

As animals age, these stem cells become more numerous, but less effective at regenerating the blood system, Wagers says. That translates into a less effective immune system and a greater susceptibility to disease.

The researchers began by surgically joining the bloodstreams of pairs of mice that were of different ages, but nearly clones of one another.

After several weeks of sharing their blood systems with young mice, the hematopoietic stem cells of the older mice changed markedly.

Exposure to a younger animal’s blood somehow pushed the older animal’s hematopoietic stem cells back to a more youthful state, in which they were fewer in number but recovered nearly all of their blood cell-generating capacity.

When transplanted into mice whose own blood-producing cells had been eliminated by radiation, the “rejuvenated” stem cells repopulated the blood with a mixture of cell types similar to that generated by transplanted young stem cells.

No such changes occurred in the young mice in these pairings, said an HHMI release.

The new findings were published in advanced online edition of Nature.

Lots of people love mushrooms, especially sauteed with a nice steak. But did you know that there are certain kinds of mushrooms that can infect the sinus passages?

The mushrooms we’re talking about here aren’t the kind used for food, but they belong to the species known as fungi, including certain types of molds. Fungi are organisms that resemble plants, but unlike genuine plants can’t produce their own food through the process of photosynthesis. Usually these types of fungi live in our warm, moist nasal passages without causing any problems. However, when a body’s resistance is low, these fungi can become harmful.

Fungi usually feed on dead organic matter, which is why food mushrooms are found living at the roots of trees and in the carpet of leaves composting on a forest floor. Fungi like dark, warm, wet places, just like the insides of our noses. Sometimes fungi can feed on other living organisms, such as the mucus membranes inside nasal and sinus passages. When that happens, these membranes become inflamed and can become infected.

Molds are a kind of microscopic fungi related to mushrooms. To reproduce themselves, they release spores that can sail through the air like pollen. Fungi of this type can be found throughout the year in many regions. They’re affected by the weather – when’s warm and rainy, or even warm and humid, you can expect an increase in the growth of molds. That’s one of the reasons why it can be essential to control the humidity in a home, to reduce the likelihood of mold growing in the walls, especially on building materials that contain a lot of cellulose (once again, that’s a wood-derived product of the kind that outdoor fungi are so fond of eating).

Common types of mold found indoors include Aspergillus and its subspecies (A. Flavus, A. Versicolor); Cladosporium; Penicillium; Alternaria and the toxic “Black Mold, ” Stachybotrys atra (S. Atra). Any of these indoor molds can be the microscopic mushrooms that infect sinuses. Sometimes they produce effects that are quite toxic to the human body. The best way to avoid such an infection is by working to prevent their growth in the home, and through good health habits, especially frequent hand washing and other forms of hygiene.

If you do become infected, see your doctor immediately. And if you suspect fungi may have invaded your home, contact a building specialist to conduct tests. It’s better to be safe than suffer with a fungal infection.

The stigma linked to mentally ill people of being dangerous is completely unwarranted, says a new study, which found that homicides of strangers by people with schizophrenia are exceptionally rare and unpredictable events.
The international study initiated by a team of Sydney researchers, is one of a series of studies of homicide by the mentally ill by two senior lecturers in psychiatry at the University of New South Wales, Dr Olav Nielssen at St Vincents Hospital and Dr Matthew Large at Prince of Wales.
An international multicentre study was necessary as there were so few stranger homicides by people with mental illness in NSW in the last 15 years. The study calculated a rate of stranger homicide by those with schizophrenia of one in 14 million population per year in advanced countries.
It also compared the characteristics of 42 patients who killed strangers with a matched sample of patients who killed family members. The stranger homicide offenders were more likely to be the homeless and to have a history of antisocial conduct. The victims were more likely to be males and the offences rarely occurred in the victim”s home or workplace. Over half of the subjects in both groups had never received treatment for schizophrenia.
“The lack of any particular distinguishing features and the extremely low base rate means that it would be impossible to predict who might commit this sort of offence and when they might occur. However, most of the patients in the study were not receiving treatment, and providing earlier treatment to first episode patients, and a good standard of care to all patients with established illness could prevent some of these tragic events,” said Nielssen.
“What the paper shows, more than anything else, is that the public fear of the mentally ill is completely misplaced. These events are so rare that they are almost impossible to study, yet the fear of serious violence by the mentally ill is a major cause of stigma,” said Large. The study was published in the leading schizophrenia journal, Schizophrenia Bulletin

Most adults and teens should be vaccinated against whooping cough (pertussis), says the American Academy of Family Physicians.

Many people believe that whooping cough is no longer a major public health concern in the United States, but health experts estimate there are up to 600,000 cases each year in adults alone, according to the AAFP.

The organization this week launched a public health initiative to promote awareness about the importance of whooping cough vaccination to protect adolescents and adults from this highly contagious respiratory disease.

“For protection against whooping cough, health experts … recommend that most adolescents and adults get a single dose of the Tdap (tetanus, diphtheria, acellular pertussis) vaccine to replace Td (tetanus and diphtheria toxoids),” Dr. Ted Epperly, president of the AAFP, said in a news release.

Washington: Scientists have come up with new ways to stop by-products from the air we breathe from harming our muscles.

Atanu Duttaroy, associate professor of biology at Howard University in Washington, D.C., and colleagues have shown how about 3 percent of the air we breathe gets converted into harmful superoxides, which ultimately harm our muscles.

They say that these superoxides lead to the creation of a toxic molecule called “reactive oxygen species” (ROS), which is shown to be particularly harmful to muscle tissue, and may lead to problems ranging from aging and frailty to Parkinson’s disease and cancer.

“At a minimum, we hope this research leads to new ways of addressing inevitable declining physical performance and other age-dependent infirmities among the elderly,” said Duttaroy.

For the study, the researchers built on their previous research showing that ROS-induced cellular damage happens in the same way in fruit flies and in mice.

They started their work with fruit flies that lack mitochondrial superoxide dismutase enzyme (SOD), which provides the primary line of defence against ROS by capturing the superoxides and converting them to water.

This lack of SOD caused the fruit flies to die within a day after hatching.

Then they used genetic manipulation to “turn on” the production of SOD separately in nerves and muscles.

SOD in nerves did not appear to make a significant difference in prolonging the fruit flies’ lives, but it did make a difference when it was activated in their muscles.

The researchers observed that the survival of fruit flies with SOD “turned on” in their muscles increased, and for several days, they remained as active as their normal counterparts.

Measurement of their muscle activity also showed that SOD helped the muscle work normally, helping survival.

The study has been published in the journal Genetics.

The health benefits of increased exposure to sunlight and vacations may explain why fewer people in northern countries die in late summer and early fall, according to a new study.

American and Greek researchers found that death rates are lowest in August in North America and Sweden, in September in the Mediterranean, and in March in Australia, CBC News reported.

The link between these times of the year and lower death rates may be due to the physiological effect of increased vitamin D production by the body due to sun exposure, coupled with the stress-lowering benefits of vacation, the study authors suggested.

Vitamin D “may have beneficial effects for cardiovascular disease, renal failure, certain malignant diseases, autoimmune disorders and infections, including influenza,” wrote Dr. Matthew Falagas, of the Alfa Institute of Biomedical Sciences in Greece, and his colleagues, CBC News reported.

Teens who start drinking before age 15 could jump-start any genetic conditions they might have that predispose them to developing alcohol dependency, according to an Australian study.

From a biological perspective, taking that first drink at a young age “may induce changes in the highly sensitive adolescent brain, which may also modify an individual’s subsequent genetic vulnerability to [alcohol dependence],” Arpana Agrawal, an assistant professor of psychiatry at Washington University School of Medicine and an author of the study, said in a university news release.

The findings, published online Sept. 18 and in the December print issue of Alcoholism: Clinical & Experimental Research, are based on a study of 6,257 adult twins.

The younger people were when they had their first drink, especially if that occurred before age 15, the more symptoms of alcohol dependency they developed, the study found. Early drinkers also tended to have an increased genetic vulnerability for alcohol.

Those who had their first drink later in life showed far fewer signs of alcohol dependency, despite the genetic predisposition, Agrawal noted.

This suggests that alcohol dependency among those who started drinking later, “while less common, are attributable to unique experiences of those individuals — for example, a traumatic life event,” she said.

Carol A. Prescott, a professor of psychology at the University of Southern California, said the findings had two possible conclusions. “Early drinking changes the course an individual is on, and is thus a direct cause of increased [alcohol dependency] risk, and early drinking is correlated with [alcohol dependency] risk and is thus an indirect indicator of … risk,” she said in the news release.

Agrawal said the findings should be used to discourage young people from experimenting with drinking early because such behavior might trigger an onset of alcohol abuse.

The researchers plan to do a similar study that looks at older and younger groups in Australia and the United States to try to duplicate their findings.

Source:  http://pubs.niaaa.nih.gov/

It is known that fingernails grow faster than toenails. Now, a new study says that the growth of both has surged by 25 per cent in the past 70 years — thanks to the modern protein-rich diet.

A team at University of North Carolina has based its findings on an analysis of a comparison of two researches, one carried out by Oxford University in 1938 and the other carried out in the 1950s, the ‘Daily Mail’ reported.

The study has revealed that big toenails now grow by more than 2 mm a month, compared with 1.65 mm in the Thirties.

Thumbnail growth rate was 3 mm a month in 1938 and 3.06 mm in the Fifties study. However, the average thumbnail now grows by 3.55 mm a month — an increase of more than half a millimetre over seven decades, it found.

According to researchers, “A rapid change in the environment, lifestyle and health conditions — such as diet, physical activity and body composition — has occurred over the past 30 years.

“Increasing trends in adolescent and adult height, birth-weight and rate of growth have been reported. Our results indicate that there may be an increased trend in fingernail and toenail growth rate as well.”

In fact, in their study, the researchers monitored 195 fingernails and 188 toenails over a period of three months to come to the conclusion.

The results found fingernails now grow by 3.47 mm every month — almost twice as fast as toenails. The nails of younger people and men grow faster. The little finger nail grows more slowly than other fingernails at a rate of 3.08 mm each month. The middle finger has fastest -growing nail.

The findings have been published in the ‘Journal Of The European Academy Of Dermatology And Venereology.’

Q I am a 19-year-old girl and am worried that I may have ruptured my hymen because of masturbation. Is that possible? Also, is it possible to get a hymenoplasty done and where can I go for one?

The best way to know if your hymen is intact or not is to get yourself examined by a doctor. The hymen can be ruptured by activities like bicycling, athletic events high jump and long jump, dancing, travelling on a motorcycle with legs on either side of the bike etc. Bleeding on masturbation or sexual intercourse is not mandatory. Statistics reveal that only 42 per cent women are born with a hymen that is likely to bleed. Also the quantum of bleeding varies from person to person. you can consult any qualified cosmetic (plastic) surgeon for hymenoplasty, the cost of which depends on the kind of hospital and doctors chosen.

Q My right testicle is bigger than the left one and I experience pain when I press it. Two years back I was hit by a cricket ball on the same testicle, but pain relief medication solved the issue at that time. Would it have caused any permanent damage?

You are probably suffering from Hydrocele, a condition in which there is fluid retention between the layers covering the testis. This fluid collection is categorised into primary and secondary. A primary hydrocele causes a painless enlargement in the scrotum on the affected side. A secondary hydrocele could be painful due to either an inflammation or a cancer in the testis. In India, the most common cause of an inflammation is filariasis which is spread through mosquitoes. The next common cause is an injury to testis as happened in your case. If the Hydrocele is large it needs to be drained through a surgery.

Q I met with a minor accident while riding a motorbike some time back. In the process, the handle bar hit my genitals, but luckily the injury wasn’t too serious. But whenever I masturbate now, I experience pain in my testicles. What could be the reason for this?
Obviously your testes have suffered some damage. The severity of the damage can be assessed only through a direct physical examination and laboratory investigations. I suggest that you consult a doctor immediately.

Q I am a 19-year-old girl and am worried that I may have ruptured my hymen because of masturbation. Is that possible? Also, is it possible to get a hymenoplasty done and where can I go for one?

The best way to know if your hymen is intact or not is to get yourself examined by a doctor. The hymen can be ruptured by activities like cycling, athletic events — high jump and long jump, dancing, travelling on a motorcycle with legs on either side of the bike etc. Bleeding on masturbation or sexual intercourse is not mandatory. Statistics reveal that only 42 per cent women are born with a hymen that is likely to bleed. Also the quantum of bleeding varies from person to person. you can consult any qualified cosmetic (plastic) surgeon for hymenoplasty, the cost of which depends on the kind of hospital and doctors chosen.

Q My right testicle is bigger than the left one and I experience pain when I press it. Two years back I was hit by a cricket ball on the same testicle, but pain relief medication solved the issue at that time. Would it have caused any permanent damage?

You are probably suffering from Hydrocele, a condition in which there is fluid retention between the layers covering the testis. This fluid collection is categorised into primary and secondary. A primary hydrocele causes a painless enlargement in the scrotum on the affected side. A secondary hydrocele could be painful due to either an inflammation or a cancer in the testis. In India, the most common cause of an inflammation is filariasis which is spread through mosquitoes. The next common cause is an injury to testis as happened in your case. If the Hydrocele is large it needs to be drained through a surgery.

Q I met with a minor accident while riding a motorbike some time back. In the process, the handle bar hit my genitals, but luckily the injury wasn’t too serious. But whenever I masturbate now, I experience pain in my testicles. What could be the reason for this?
Obviously your testes have suffered some damage. The severity of the damage can be assessed only through a direct physical examination and laboratory investigations. I suggest that you consult a doctor immediately.