Monthly Archives: July 2015

Gut bacteria can trigger depression

Bacteria has a crucial role in resulting anxiety and depression including abnormal behavior. (Source: Thinkstock Images) Bacteria has a crucial role in resulting anxiety and depression including abnormal behavior. (Source: Thinkstock Images)

Intestinal bacteria plays a key role in inducing anxiety and depression that can lead to early life stress, scientists from McMaster University in Canada have discovered.

“We have shown for the first time in a mouse model of anxiety and depression that bacteria play a crucial role in inducing this abnormal behaviour,” said Premysl Bercik, associate professor of medicine with McMaster University’s Michael G. DeGroote School of Medicine.

“It is not only bacteria but the altered bi-directional communication between the stressed host — mice subjected to early life stress — and its microbiota, that leads to anxiety and depression,” he explained.

In this study, researchers subjected mice to early life stress. Newborn mice were separated for three hours each day from their mothers and then put back with them.

Mice with complex microbiota, which had been maternally separated, displayed anxiety and depression-like behaviour, with abnormal levels of the stress hormone corticosterone.

These mice also showed gut dysfunction based on the release of a major neurotransmitter called acetylcholine.

Then, they repeated the same experiment in germ-free conditions and found that in the absence of bacteria, mice which were maternally separated still have altered stress hormone levels and gut dysfunction.

“Neonatal stress leads to increased stress reactivity and gut dysfunction that changes the gut microbiota which, in turn, alters brain function,” Bercik noted in a paper published in the journal Nature Communications.

The data show that relatively minor changes in microbiota profiles or its metabolic activity induced by neonatal stress can have profound effects on host behaviour in adulthood.

Source Article from http://indianexpress.com/article/lifestyle/health/gut-bacteria-can-trigger-depression/

New blood cancer drug enters phase II clinical trials

Promising to eliminate blood cancer in its first human trial is now in phase II clinical trials, a new study says. (Source: Thinkstock Images) Promising to eliminate blood cancer in its first human tria by a drug is now in phase II clinical trials, a new study says. (Source: Thinkstock Images)

A new drug found promising for treating blood cancer in its first human trial is now in phase II clinical trials, a new study says.

The drug coaxes dormant cancer stem cells, residing in the bone marrow, to begin differentiating and exit into the blood stream where they can be destroyed by chemotherapy agents.

“This drug gets that unwanted house guests to leave and never come back,” said the study’s senior author Catriona Jamieson, associate professor of medicine at University of California, San Diego School of Medicine in the US.

“It is a significant step forward in treating people with refractory or resistant myeloid leukemia, myelodysplastic syndrome and myelofibrosis,” Jamieson said.

“It is a bonus that the drug can be administered as easily as an aspirin, in a single, daily oral tablet,” Jamieson noted.

For the first-in-human study conducted between 2010-2012, the drug called PF-04449913 was tested in 47 adults with blood and marrow cancer.

They received escalating daily doses of the drug in 28-day cycles.

Treatment cycles were repeated until a participant experienced unacceptable adverse effects without evidence of clinical improvement.

The drug elicited clinical activity sufficient to establish proof-of-concept for the treatment in 23 individuals, or nearly half the study participants.

Given the promising results, the drug’s efficacy as a treatment for different types of blood cancer is now being investigated in five phase II clinical trials.

“Our hope is that this drug will enable more effective treatment to begin earlier and that with earlier intervention, we can alter the course of disease and remove the need for, or improve the chances of success with, bone marrow transplantation,” Jamieson said.

The study was published online in the journal The Lancet Haematology.

Source Article from http://indianexpress.com/article/lifestyle/health/new-blood-cancer-drug-enters-phase-ii-clinical-trials/

Healthy dose of adventure can ‘treat’ children with cancer

children-main Children with cancer may benefit from a different kind of treatment – a healthy dose of adventure such as dog sledding, suggests new research (Source: Thinkstock Images)

Children with cancer may benefit from a different kind of treatment – a healthy dose of adventure such as dog sledding, suggests new research.

The study followed eleven children aged 10-18 years, and five chaperones including doctors and nurses, on a dog sledding expedition to Canada organised by the French non-profit organisation Sourire a la Vie.

“What I learned from this study is that we doctors have the false belief that kids with cancer cannot practice sport because they are too tired or weak from their treatments,” said corresponding author of the study Nicolas Andre from Assistance Publique Hopitaux de Marseille, France.

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“These perceptions are at least partly wrong,” Andre said.

“Adapted physical activities can be performed by most children with cancer even during their treatment and can bring a lot to children,” Andre noted.

All of the eleven children received adapted physical training and exercises before the expedition.

The children successfully completed the programme without harm – and they demonstrated statistically significant improvement in both physical and psychological health.

The findings appeared in the journal ecancermedicalscience.

Based on the success of this study, the researchers said they would initiate a randomised trial to evaluate the benefits of adapted physical activities for children with cancer.

Source Article from http://indianexpress.com/article/lifestyle/health/healthy-dose-of-adventure-can-treat-children-with-cancer/

Skipping breakfast may be bad for diabetics

Diabetes patients who miss their morning meal have higher-than-usual surges in blood sugar after lunch and dinner, the study found. (Source: Thinkstock Images) Diabetes patients who miss their morning meal have higher-than-usual surges in blood sugar after lunch and dinner, the study found. (Source: Thinkstock Images)

People with type 2 diabetes who skip breakfast and fast until noon may have blood sugar spikes throughout the day, a small study suggests.

When 22 patients with type 2 diabetes missed their morning meal, they had higher-than-usual surges in blood sugar after lunch and dinner, the study found.

Skipping breakfast was also linked to less efficient processing of glucose by the body, or a reduced ability to convert blood sugar into energy.

The researchers had expected that skipping breakfast wouldn’t be healthy. But they were surprised at the extent to which glucose metabolism suffered, simply because participants hadn’t eaten breakfast, said lead author Daniela Jakubowicz of Tel Aviv University.

“This means reducing the amount of starch and sugars in lunch and dinner will have no effect on reducing elevated glucose levels if patients also skip breakfast,” she said by email.

Globally, about one in 10 adults have diabetes, according to the World Health Organization. Like the patients in this study, most have type 2 diabetes, which is associated with obesity and aging and occurs when the body can’t make or process enough of the hormone insulin.

Previous research has linked skipping breakfast to an increased risk for weight gain and diabetes, Jakubowicz and colleagues note in the journal Diabetes Care.

The current study involved 12 men and 10 women who were about 57 years old on average, and overweight.

On test days, patients were asked to fast overnight, then come to the clinic for blood tests and either two or three meals, depending on which part of the experiment they were completing.

Participants consumed the same balanced meal with the same number of calories for lunch and dinner.

Two to four weeks later, they repeated the process, but switching to either eat or skip breakfast – whatever they hadn’t done in the first phase.

On test days when patients skipped breakfast, their blood sugar was 40 percent higher after lunch and 25 percent higher after dinner than on the days when they had three meals.

Skipping breakfast may have made it difficult for the pancreas to produce the right amount of insulin to properly control blood sugar, Jakubowicz said. Normally, beta cells in the pancreas release insulin in response to elevated levels of sugar in the blood.

Missing the morning meal may cause the beta cells to “forget their vital role,” she said, delaying the release of insulin and allowing blood sugar levels to remain high for longer periods of time after lunch and dinner.

Because the study only included people with diabetes, it’s not clear whether healthy people would experience similar blood sugar spikes after skipping breakfast, the researchers acknowledge. It’s also unclear how long the blood sugar spikes might last.

It’s also possible that the last meal the night before might influence blood sugar the following day regardless of whether or not they ate breakfast, said Tanya Zilberter, a researcher in metabolic diseases with the Institut de Neurosciences des Systèmes in Marseille, France.

A late dinner might lead to high blood sugar the next day, Zilberter, who wasn’t involved in the study, said by email.

“It might be that the duration of the overnight fast matters more than the timing of the first meal of the day,” Zilberter said.

Source Article from http://indianexpress.com/article/lifestyle/health/skipping-breakfast-may-be-bad-for-diabetics/

‘Leaky’ vaccines could make diseases more deadly: study

More harmful viruses can evolve from the use of so-called "leaky" vaccines, researchers, including one of Indian-origin, have confirmed for the first time. More harmful viruses can evolve from the use of so-called “leaky” vaccines, researchers, including one of Indian-origin, have confirmed for the first time.

More harmful viruses can evolve from the use of so-called “leaky” vaccines, researchers, including one of Indian-origin, have confirmed for the first time.

Scientific experiments with the herpesvirus such as the one that causes Marek’s disease in poultry have confirmed the highly controversial theory that some vaccines could allow more-virulent versions of a virus to survive, putting unvaccinated individuals at greater risk of severe illness.

“The challenge for the future is to identify other vaccines that also might allow more-virulent versions of a virus to survive and possibly to become even more harmful,” said Andrew Read, an author of the paper published in the journal PLoS Biology, from the Penn State University.

“When a vaccine works perfectly, as do the childhood vaccines for smallpox, polio, mumps, rubella, and measles, it prevents vaccinated individuals from being sickened by the disease, and it also prevents them from transmitting the virus to others,” Read said.

These vaccines are a type that is “perfect” because they are designed to mimic the perfect immunity that humans naturally develop after having survived one of these diseases.

“Our research demonstrates that another vaccine type allows extremely virulent forms of a virus to survive – like the one for Marek’s disease in poultry, against which the poultry industry is heavily reliant on vaccination for disease control,” said Venugopal Nair, who led the research team in the UK where the experimental work was carried out.

“These vaccines also allow the virulent virus to continue evolving precisely because they allow the vaccinated individuals, and therefore themselves, to survive,” said Nair, who is the head of the Avian Viral Diseases programme at the Pirbright Institute in UK.

Less-than-perfect vaccines create a ‘leaky’ barrier against the virus, so vaccinated individuals sometimes do get sick, but typically with less-virulent symptoms.

Because the vaccinated individuals survive long enough to transmit the virus to others, the virus also is able to survive and to spread throughout a population.

“In our tests of the leaky Marek’s-disease virus in groups of vaccinated and unvaccinated chickens, the unvaccinated died while those that were vaccinated survived and transmitted the virus to other birds left in contact with them,” Nair said.

“Our research demonstrates that the use of leaky vaccines can promote the evolution of nastier ‘hot’ viral strains that put unvaccinated individuals at greater risk,” he said.

The World Health Organisation recently reported laboratory-confirmed cases in China of human infection with the avian influenza virus, researchers said.

“We humans never have experienced any contagious disease that kills as many unvaccinated hosts as these poultry viruses can, but we now are entering an era when we are starting to develop next-generation vaccines that are leaky because they are for diseases that do not do a good job of producing strong natural immunity – diseases like HIV and malaria,” Read added.

Source Article from http://indianexpress.com/article/lifestyle/health/leaky-vaccines-could-make-diseases-more-deadly-study/

Ban Indian doctors’ white coats, they spread infections: Study

Banning Indian doctors and medical students from wearing long-sleeved white coats could reduce the spread of infections in hospitals Banning Indian doctors and medical students from wearing long-sleeved white coats could reduce the spread of infections in hospitals

Banning Indian doctors and medical students from wearing long-sleeved white coats could reduce the spread of infections in hospitals, says a new study.

“Long sleeved coats spread infection and lead to avoidable harm and cost to patients,” said Edmond Fernandes, a postgraduate at Yenepoya Medical College in Bengaluru.

“Every hospital should have a committee to check and respond to hospital acquired infections,” he added.

“But an easy win would be for India’s ministry of health to ban doctors and medical students from wearing white coats, to reduce the harm and cost that results from hospital acquired infections,” Fernandes said in the study published in the journal The BMJ.

“Although long sleeved white coats have traditionally been worn by doctors since the 19th century, we now know that white coats harbour potential contaminants and contribute considerably to the burden of disease acquired in hospital by spreading infection,” Fernandes added.

He said that in India, changing areas in hospitals are rare because of space constraints, so white coats are commonly worn by students coming from college and outside the hospital. They are also often left on chairs, tables, and in corridors.

He added that in many cities in India some junior doctors are also now seen wearing white coats in shopping malls and cinemas too, and then they enter sterile zones in the hospital in the same attire.

“Given India’s tropical climate, common sense indicates that we should discourage wearing white coats that are washed perhaps only every few weeks,” Fernandes said.

In 2007, the United Kingdom took the landmark decision to ban long sleeved white coats – and that in 2009, the American Medical Association wanted to follow suit and dump the white coats, “but the proposal was dismissed because clinicians wanted to keep their traditional gowns”, he said.

“White coats are mere symbolism and wearing them does not itself confer status or professionalism,” Fernandes added.

“Dressing presentably and sporting a smile are more important than white coats and that institutions should give every medical student and doctor a recognisable name badge to wear,” he said.

Source Article from http://indianexpress.com/article/lifestyle/health/ban-indian-doctors-white-coats-they-spread-infections-study/

New drug may block malaria in its tracks

The new drug acts as a roadblock for malaria, curing mice of established infection, according to a study. The new drug acts as a roadblock for malaria, curing mice of established infection, according to a study.

Scientists have developed a new drug that shows hope for stopping deadly malaria in its track.

The new drug acts as a roadblock for malaria, curing mice of established infection, according to a study. Treatment was not associated with obvious side effects, suggesting that the drug may also be safe and effective in humans.

In 2011, a group of scientists at the Wellcome Trust Sanger Institute in the UK discovered that a human protein called basigin was required for all strains of Pf to invade red blood cells, an essential stage of the parasite’s life cycle. Antibodies that block the interaction between basigin and the parasite protein PfRH5 were known to block Pf infection in culture, and the Sanger Institute group has now developed a nontoxic anti-basigin drug (called Ab-1) that cured mice of established blood infection.

The transition of promising new drugs from mice to humans usually requires costly and time-consuming clinical trials, but the path for Ab-1 may be less arduous.

Basigin has also been implicated in the progression of certain cancers and in graft-versus-host disease in transplant patients, and drugs that block the protein have already proven safe and effective in patients and are already in clinical use.

According to the World Health Organization malaria currently infects more than 200 million people worldwide and accounts for more than 500,000 deaths per year.

Malaria has been a problem in India for centuries. At present, official figures for malaria in India, available at NVBDCP, indicate 0.7-1.6 million confirmed cases and 400-1,000 deaths annually.

The disease is caused by infection with the parasite Plasmodium falciparum (Pf), and although the disease can be treated with anti-malarial drugs, the drugs are harsh and resistance often develops.

The study is published in the Journal of Experimental Medicine.

Source Article from http://indianexpress.com/article/lifestyle/health/new-drug-may-block-malaria-in-its-tracks/

How night shift may lead to cancer

The study conducted on mice suggests that poor sleeping patterns have been "unequivocally" shown to lead to cancer, and scientist have warned women with a family risk of breast cancer to never take up work shifts, the BBC reported. The study conducted on mice suggests that poor sleeping patterns have been “unequivocally” shown to lead to cancer, and scientist have warned women with a family risk of breast cancer to never take up work shifts, the BBC reported.

Adding to the concerns about the damaging impact of shift work on health, a new study has found that irregular sleeping patterns maybe linked to cancer.

The study conducted on mice suggests that poor sleeping patterns have been “unequivocally” shown to lead to cancer, and scientist have warned women with a family risk of breast cancer to never take up work shifts, the BBC reported.

However, they added that further human tests were needed.

The risk of the disease could be because of the increase in disruption of body’s internal rhythm or body clock, but the link is uncertain because the type of person who works shifts may also be more likely to develop cancer due to factors such as social class, activity levels or the amount of vitamin D they get.

The study claims to be the first to “unequivocally show a link between chronic light-dark inversions and breast cancer development.”

The researchers assume that the equivalent effect could be an extra 10kg (1st 8lb) of body weight or for at-risk women getting cancer about five years earlier.

Dr Michael Hastings, from the UK’s Medical Research Council, said that the general public health message coming out is that shift work, particularly rotational shift work was a stress and hence had consequences.

The findings are reported in Current Biology.

Source Article from http://indianexpress.com/article/lifestyle/health/how-night-shift-may-lead-to-cancer/

Just one night of sleep loss can alter your genes

sleeping-main Genes that control the biological clocks in cells throughout the body are altered after losing just a single night of sleep

Genes that control the biological clocks in cells throughout the body are altered after losing just a single night of sleep, scientists have found.

“Previous research has shown that our metabolism is negatively affected by sleep loss, and sleep loss has been linked to an increased risk of obesity and type 2 diabetes,” said Jonathan Cedernaes, a researcher at Uppsala University.

“Since ablation of clock genes in animals can cause these disease states, our current results indicate that changes of our clock genes may be linked to such negative effects caused by sleep loss,” he said.

For the study the researchers studied 15 healthy normal-weight men who on two separate occasions came to the lab for almost 2-night long stays.

During the second night the participants slept as usual (over 8 hours) in one of the two sessions, while they were kept awake in the other of these sessions, but in random order.

To minimise the influence of various environmental factors, light conditions, food intake and activity levels in the lab were strictly controlled and the participants were bed-restricted when they were kept awake.

Following the second night on both occasions that the men were studied, small tissue samples were taken from the superficial fat on the stomach, and from the muscle on the thigh – two kinds of tissues that are important for regulating metabolism and controlling blood sugar levels.

Blood samples were also taken before and after the participants had consumed a sugar solution to test their insulin sensitivity, a practice commonly done to exclude the presence of diabetes or a metabolic state called impaired insulin sensitivity, which can precede type-2 diabetes.

Molecular analyses of the collected tissue samples showed that the regulation and activity of clock genes was altered after one night of sleep loss.

The activity of genes is regulated by a mechanism called epigenetics. This involves chemical alterations to the DNA molecule such as methyl groups – a process called methylation – which regulates how the genes are switched on or off.

The researchers found that clock genes had increased numbers of such DNA marks after sleep loss. They also found that the expression of the genes, which is indicative of how much of the genes’ product is made, was altered.

“As far as we know, we are the first to directly show that epigenetic changes can occur after sleep loss in humans, but also in these important tissues,” said Cedernaes.

“It was interesting that the methylation of these genes could be altered so quickly, and that it could occur for these metabolically important clock genes,” he said.

The changes that the researchers observed were however different in the adipose tissue and the skeletal muscle.

“This could suggest that these important molecular clocks are no longer synchronised between these two tissues,” Cedernaes said.

Source Article from http://indianexpress.com/article/lifestyle/health/just-one-night-of-sleep-loss-can-alter-your-genes/

Forced eating does no good to children

"If children are pushed to eat everything on their plates, they may stop relying on their own body's signals, and eat until the parents are happy," the study said. “If children are pushed to eat everything on their plates, they may stop relying on their own body’s signals, and eat until the parents are happy,” the study said.

Parents who force their kids to finish everything served on their plates may be doing more harm than good. Forced eating disrupts normal eating behaviour, making children vulnerable to unhealthy weight gain, shows research.

In order to promote the development of normal eating behaviour, it is important for children to decide how much they want to eat.

“If children are pushed to eat everything on their plates, they may stop relying on their own body’s signals, and eat until the parents are happy,” the study said.

“We have looked to see if physical activity, television time and appetite traits can explain why some children’s body mass index (BMI) increases more than others’ do,” said Silje Steinsbekk, assistant professor at the Norwegian University of Science and Technology.

The findings published in the Journal of Paediatric Psychology showed that the way children related to food and eating was crucial. Physical activity and TV viewing, on the other hand, did not explain why the BMI of some children increased more as compared to others.

“Our study shows that BMI increases more in children where food especially triggers their eating behaviour. Their food intake is controlled more by the sight and smell of food, and less by an inner experience of hunger,” Steinsbekk said.

The research is part of a long-term study that looks at children’s psychological and psychosocial development over several years.

The same children are examined every two years, and in this particular study, the researchers dealt with data from when the children were four, six and eight years old.

Source Article from http://indianexpress.com/article/lifestyle/health/forced-eating-does-no-good-to-children/