2nd Sep 2013, 12:46 PM #451
Re: Health Bulletin
Mosquitoes can smell humans better at night
Malaria-causing mosquitoes are able to smell humans better at night, a new study has found.
The major malaria vector in Africa, the Anopheles gambiae mosquito, smells major human host odourants better at night, scientists said.
Anopheles gambiae is the primary species that is responsible for the transmission of malaria in sub-Saharan Africa , with approximately 300 million infections and 1 million deaths annually.
The study reported an integrative approach to examine the mosquito's ability to smell across the 24-hour day and involved proteomic, sensory physiological, and behavioural techniques.
Researchers examined the role for a major chemosensory family of mosquito proteins , odourant-binding proteins (OBPs), in the daily regulation of olfactory sensitivities in the malarial mosquito . It is thought that OBPs in the insect antennae and mouth parts function to concentrate odourant molecules and assist in their transport to the actual olfactory receptors , thereby allowing for odourant detection.
The team revealed daily rhythmic protein abundance of OBPs, having higher concentrations in the mosquito's sensory organs at night than during the day. This discovery could change the way we look at protecting ourselves from these pests. The study utilised mass spectrometry to quantify protein abundance in mosquito sensory organs, and electroantennograms to determine the response induced by host odourants at different times of the day
3rd Sep 2013, 11:34 AM #452
Re: Health Bulletin
Australian doctors create history in IVF technology
A team at Melbourne IVF and the Royal Melbourne Hospital in Australia have achieved a breakthrough by helping an infertile woman to conceive through an ovarian tissue transplanted into her abdomen.
The breakthrough, in a world first, has the potential to revolutionize the existing fertility treatment, reports the Sydney Morning Herald.
Twenty six-year-old Vali is 26 weeks pregnant with twins after previously being declared infertile because of a treatment for ovarian cancer.
The doctors managed to help the women produce two healthy eggs after transplanting her own frozen ovarian tissue into her abdomen.
Gab Kovas, medical director of Monash IVF, said the breakthrough was very exciting.
"It makes me quite convinced that the optimal way for preserving fertility will be taking ovarian tissue," the report quoted Kovas as saying.
"If I had a patient who was going to lose their fertility to cancer treatment, I would offer it from now on," he said.
Kate Stern, Vali's fertility specialist, said it had taken years of daily monitoring to achieve the pregnancy.
"When it happened, I think we all had a good cry together really," Stern said.
"Vali had remained strong throughout. Never once did she waver and tell us it was too hard and she wanted to give up," she added.
The sample of Vali's ovarian tissue was kept frozen for seven years and was taken from her cancer-free ovary.
The new breakthrough could be a blessing for women with conditions such as ovarian cancer where the treatment could make them infertile.
3rd Sep 2013, 11:38 AM #453
Re: Health Bulletin
Heart attack risk rises in winter, dips in summer
The risk of getting a heart attack is highest in winter and lowest in summer, according to latest research based on analysis of more than 100,000 patients in seven European countries.
The researchers found that levels of several cardiovascular risk factors (such as blood pressure, waist circumference and total cholesterol) were higher in winter (January to February) and lower in summer (June to August) compared to the annual average.
The findings were presented at the congress of the European Society of Cardiology currently meeting at Amsterdam by Dr Pedro Marques-Vidal from Switzerland. The study used cross-sectional data from 10 population based studies in 7 countries. Information was obtained on cardiovascular risk factors in 107,090 subjects aged 35 to 80 years. The country breakdown was as follows: 21,128 subjects in Belgium, 15,664 in Denmark, 1,626 in France, 18,370 in Italy, 25,532 in Norway, 9,359 in Russia and 15,411 in Switzerland.
Levels of blood pressure, lipids, glucose, body mass index (BMI, kg/m2) and waist circumference were compared according to season. All data were adjusted for age, gender and smoking. Data on blood pressure, lipids and glucose were adjusted for BMI and whether or not the patient was taking medication.
'The study suggests that particular care with CVD prevention should be taken over the winter months,' said principal investigator Pedro Marques-Vidal. 'It is important that emergency resources are strengthened in winter.'
Systolic blood pressure levels were on average 3.5 mmHg lower in summer than in winter. One explanation for the lower blood pressure levels seen in the summer, he speculated, is that higher ambient temperatures lead to vasodilation (broadening of blood vessels) and perspiration. It is also possible that higher levels of physical activity and a different dietary intake in summer may reduce obesity.
Waist circumference was on average 1 cm smaller in summer than in winter, while total cholesterol was, on average, 0.24 mmol/L lower in summer than in winter. Dr Marques-Vidal said: ""We observed a seasonal variation in waist circumference but BMI did not change throughout the year. We have no clear explanation for this finding. Total cholesterol may increase during the winter because of changes in eating habits. There was no seasonal variation in glucose, probably because several cohorts did not collect blood samples in the fasting state. We have begun a study on seasonality of food intake which may help explain these findings.""
"Our large scale study shows that some cardiovascular risk factors take holidays over the summer. This may explain why deaths from cardiovascular disease are higher in winter than summer. People need to make an extra effort to exercise and eat healthily in the winter to protect their health," Dr Marques-Vidal added.
""Our team is currently conducting another study to find out if the seasonal pattern in cardiovascular risk factors reverses in the southern hemisphere, where seasons are inverted relative to the northern hemisphere. Based on preliminary data, it does seem to be the case. The overall study is expected to collect information on almost 200,000 subjects from over 12 countries," he said.
4th Sep 2013, 12:29 PM #454
Re: Health Bulletin
Coffee can combat diseases: Coffee Board
Coonoor, Sept 3: The 120th annual conference of UPASI (United Planters Association of Southern India) here has provided an opportunity for the Coffee Board of India to spread health benefits of coffee that includes coffee and liver health and the role of coffee in combating type-II diabetes and Parkinson's disease.
The officials on duty, at the stall put up by the Coffee Board, at the exhibition connected with the conference at UPASI, were seen distributing pamphlets educating on the health benefits of coffee, besides briefing the visitors on the varieties and grades of coffee beans that are grown in the country.
An official said coffee is one of the most widely researched ingredients and the growing body of scientific research shows that coffee, when drunk in moderation (around four to five cups a day), is safe for healthy adults. Coffee in a measure is a treasure, the official pointed.
“A study by Prof. D'Amicis, head of the Nutrition Information Unit in Rome, showed that role of coffee as liver protective agent as it reduces the risk of cirrhosis of the liver and its role in reducing the gallstone formation.
The pamphlets issued by the Coffee Board on "coffee and diabetes" noted that for several years research studies have been published consistently suggesting that coffee drinking may be protective against the development of type II diabetes.
However, the exact mechanism by which coffee may be protective is not yet fully understood.
On Parkinson's disease, a research conducted in 2002 by Hernan and his group demonstrated that coffee drinkers had 31% less chance of developing Parkinson's disease than non-coffee drinkers.
However, the mechanism of action for this effect has yet to be fully identified.
4th Sep 2013, 01:10 PM #455
Re: Health Bulletin
Sad face? It's a sign of sleep deprivation
If your friend's sporting droopy eyelids, more wrinkles and redder-than-usual eyes, don't presume he's suffering from a hangover. A new research from Sweden suggests that such facial changes are the signs of sleep deprivation.
Facial features such as the eyes, mouth and skin could serve as cues of sleep loss, say the researchers from Stockholm University in Sweden.
Sleep deprivation is a common phenomenon across the world; the American Academy of Sleep Medicine reports that about 30 % of American adults regularly don't get sufficient sleep.
The Swedish results showed that the faces of sleep-deprived people were perceived as having more hanging eyelids, redder eyes, more swollen eyes and darker circles under the eyes. Sleep deprivation also was associated with paler skin, more wrinkles or fine lines, and a droopy mouth. People also looked sadder when sleep-deprived than after normal sleep, and sadness was related to looking fatigued.
"Since faces contain a lot of information on which humans base their interactions with each other, how fatigued a person appears may affect how others behave toward them," said the study's lead author Tina Sundelin. "This is relevant not only for private social interactions, but also official ones such as with healthcare professionals and in public safety."
The study, which appeared in the September issue of the journal "Sleep", looked at 10 subjects who were photographed on two separate occasions: after eight hours of normal sleep and after 31 hours of sleep deprivation. Forty participants rated the 20 facial photographs with respect to 10 facial cues, fatigue and sadness.
6th Sep 2013, 10:26 AM #456
Re: Health Bulletin
Potential cure emerges for Down Syndrome
US researchers may have identified a compound that appears to reverse the learning deficits associated with Down Syndrome in lab mice.
While the use of the compound, a small molecule known as a sonic hedgehog pathway agonist, has not been proven safe for testing on people with Down Syndrome, researchers said Wednesday their experiments hold promise for developing drugs similar to it, reports Xinhua.
Down Syndrome is one of the most common chromosomal abnormalities in children, and a leading cause of intellectual disability.
It occurs when people have three instead of the two usual copies of the chromosome 21.
As a result of this "trisomy", people with Down Syndrome have extra copies of more than 300 genes, leading to intellectual disabilities, distinctive facial features and sometimes heart problems and other health effects.
In their study, the researchers from the Johns Hopkins University and the US National Institute of Health conducted experiments on mice to give them extra copies of about half of the genes found in humans.
The researchers injected the mice the compound right after their birth and found that single injection enabled the cerebellum of the rodents' brains to grow to a normal size.
"Most people with Down Syndrome have a cerebellum that's about 60 percent of the normal size," lead author Roger Reeves of the Johns Hopkins University School of Medicine argued.
"We treated the Down Syndrome-like mice with a compound we thought might normalise the cerebellum's growth, and it worked beautifully," he said.
"What we didn't expect were the effects on learning and memory, which are generally controlled by the hippocampus, not the cerebellum," he said.
The team tested the mice who had been given the dose with the mice who suffered with the syndrome, and normal mice in a variety of ways, and found that the treated mice did just as well as the normal ones on a test of locating a platform while swimming in a so-called water maze.
Further research, however, is needed to know why exactly the treatment works and if it can be altered for human use, the researchers wrote in the journal Science Translational Medicine.
6th Sep 2013, 10:26 AM #457
Re: Health Bulletin
Hygiene may raise risk of Alzheimer's
Better hygiene in wealthy nations may have played a part in increased rates of Alzheimer's disease, researchers have claimed.
Populations in high-income, more urbanized and industrialized countries have higher rates of the disease.
A study from the University of Cambridge has suggested that this could be because better hygiene in these areas has greatly reduced contact with bacteria and viruses, leading to poorly developed immune systems that leave the brain more exposed to the inflammation associated with Alzheimer's disease.
Researchers analysed Alzheimer's rate in 192 countries and applied age standardization to remove differences in birth rate, life expectancy and population age structure. They found that countries with higher levels of sanitation had higher rates of Alzheimer's. However, the Alzheimer's Society cautioned against pinning the causes to one factor.
6th Sep 2013, 10:27 AM #458
Re: Health Bulletin
Acid story: LSD may be good for you, says study
The late acid guru Dr Timothy Leary would have claimed to have known it all along. After conducting an exhaustive study on tens of thousands of Americans, a team of Norwegian scientists has concluded that LSD may actually be good for you.
Researchers Pal-Orjan Johansen and Teri Krebs from Norway's University of Science and Technology in Trondheim examined American drug-use surveys carried out between 2001 and 2004 on over 130,000 US citizens, of which 22,000 had used a psychedelic drug such as LSD at least once in life.
The results may not amount to an appeal to "turn on, tune in and drop out", but they appear to overturn the opinion long-held in parts of the medical establishment that LSD and other "mind-enhancing" drugs automatically result in debilitating flashbacks, uncontrollable paranoia attacks and a desire to leap off buildings.
In the science journal PLOS One, Johansen and Krebs wrote: "There were no significant associations between lifetime use of any psychedelics, or use of LSD in the past year, and an increased rate of mental health problems. Rather, in several cases psychedelic use was associated with a lower rate of mental health problems."
In an interview with news website The Local, Johansen said that expert studies which attempt to discover whether psychedelic drugs such as LSD, mescaline and the "magic mushroom" drug psilocybin are harmful had not demonstrated that they caused chronic health problems. The scientists claimed the notions stemmed from a small number of case reports on patients who were already suffering from some form of mental illness.
They added that both psychedelic drug use and the onset of mental illness tended to occur in late adolescence, which in the past had led researchers to wrongly attribute mental problems to LSD.
They concluded in a report published last year that a single dose of LSD was a highly effective treatment for alcoholism. They established that 59% of patients who had been given a dose of LSD had either stopped drinking completely or were drinking less.
8th Sep 2013, 01:48 PM #459
Re: Health Bulletin
Study: The right bacteria might help fight obesity
Different kinds of bacteria that live inside the gut can help spur obesity or protect against it, say scientists at Washington University in St. Louis who transplanted intestinal germs from fat or lean people into mice and watched the rodents change.
And what they ate determined whether the good germs could move in and do the job.
Thursday's report raises the possibility of one day turning gut bacteria into personalized fat-fighting therapies, and it may help explain why some people have a harder time losing weight than others do.
"It's an important player," said Dr. David Relman of Stanford University, who also studies how gut bacteria influence health but wasn't involved in the new research. "This paper says that diet and microbes are necessary companions in all of this. They literally and figuratively feed each other."
The research was reported in the journal Science.
We all develop with an essentially sterile digestive tract. Bacteria rapidly move in starting at birth -- bugs that we pick up from mom and dad, the environment, first foods. Ultimately, the intestine teems with hundreds of species, populations that differ in people with varying health. Overweight people harbor different types and amounts of gut bacteria than lean people, for example. The gut bacteria we pick up as children can stick with us for decades, although their makeup changes when people lose weight, previous studies have shown.
Clearly, what you eat and how much you move are key to how much you weigh. But are those bacterial differences a contributing cause of obesity, rather than simply the result of it? If so, which bugs are to blame, and might it be possible to switch out the bad actors?
To start finding out, Washington University graduate student Vanessa Ridaura took gut bacteria from eight people -- four pairs of twins that each included one obese sibling and one lean sibling. One pair of twins was identical, ruling out an inherited explanation for their different weights. Using twins also guaranteed similar childhood environments and diets.
She transplanted the human microbes into the intestines of young mice that had been raised germ-free.
The mice who received gut bacteria from the obese people gained more weight -- and experienced unhealthy metabolic changes -- even though they didn't eat more than the mice who received germs from the lean twins, said study senior author Dr. Jeffrey Gordon, director of Washington University's Center of Genome Sciences and Systems Biology.
Then came what Gordon calls the battle of the microbes. Mice that harbored gut bacteria from a lean person were put in the same cages as mice that harbored the obesity-prone germs. The research team took advantage of an icky fact of rodent life: Mice eat feces, so presumably they could easily swap intestinal bugs.
What happened was a surprise. Certain bacteria from the lean mice invaded the intestines of the fatter mice, and their weight and metabolism improved. But the trade was one-way -- the lean mice weren't affected.
Moreover, the fatter mice got the bacterial benefit only when they were fed a low-fat, high-fiber diet. When Ridaura substituted the higher-fat, lower-fiber diet typical of Americans, the protective bug swap didn't occur.
Why? Gordon already knew from human studies that obese people harbor less diverse gut bacteria. "It was almost as if there were potential job vacancies" in their intestines that the lean don't have, he explained.
Sure enough, a closer look at the mice that benefited from the bug swap suggests a specific type of bacteria, from a family named Bacteroidetes, moved into previously unoccupied niches in their colons -- if the rodents ate right.
How might those findings translate to people? For a particularly hard-to-treat diarrheal infection, doctors sometimes transplant stool from a healthy person into the sick person's intestine. Some scientists wonder if fecal transplants from the lean to the fat might treat obesity, too.
But Gordon foresees a less invasive alternative: Determining the best combinations of intestinal bacteria to match a person's diet, and then growing those bugs in sterile lab dishes -- like this study could -- and turning them into pills. He estimates such an attempt would take at least five more years of research.
9th Sep 2013, 12:49 PM #460
Re: Health Bulletin
very informative and intersting !