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the bra does not increase the risk of breast cancer

Monday, September 15, 2014 / No Comments

In the United States, a survey of over 1,500 women over the age of 55 on their clothing habits in their lives shows no correlation between the occurrence of mammary tumors and wearing this underwear, often accused.

Here's a rumor that persists. Many web or social networking sites claim: wear a bra increases the risk of developing breast cancer. At issue, in particular, the compression of the breasts. American researchers prefer to cut short: "There is no relationship between use these below and the risk of carcinoma." 

Researchers at the Cancer Research Center Fred Hutchinson (Seattle) followed 1,513 postmenopausal women, aged 55-74 years. They were divided into 3 groups: 454 had developed ductal carcinoma; 590 lobular carcinoma; 469 did not suffer any type of cancer. Through personal interviews, the scientists were able to collect a variety of information about the participants: family history of cancer or their habits regarding the use of the fastener (the age at which they began to use, how often wore, whether they preferred the following with or without reinforcements ...). 

The result, according to Dr. Lu Chen, lead author of the study, "there is no evidence that wearing a bra increases the risk of breast cancer. Probabilities were similar, regardless of the number of hours per day, the presence of reinforcement or the age at which started using ". What they say ...

Some sleeping pills increase the risk of Alzheimer's

Saturday, September 13, 2014 / No Comments

The long-term use of sleeping pills and some drugs against anxiety benzodiazepine could significantly increase the risk of developing Alzheimer's disease, according to a French-Canadian study published Wednesday.

For six years, the researchers studied 1,796 cases of Alzheimer's appear in a health insurance program in Canada and compared them to 7,000 healthy people of the same age and sex. In the study published in the website of the British Medical Journal, showed that benzodiazepines for more than three months was associated with an increased risk of Alzheimer's by up to 51%. The association was particularly related to the duration of exposure and was greater when benzodiazepines are used with a long duration of action.


The study authors, including researchers from Inserm and the University of Montreal, cautioned that the results reinforce the suspicion of a possible direct link between benzodiazepines and Alzheimer's disease, although this link has not yet been confirmed. Benzodiazepines, they note, are undoubtedly valuable for the treatment of anxiety disorders and insomnia temporary tools. But they add that the treatment should be brief and should not exceed three months.

Benzodiazepine use should be limited in time

The study results are consistent with the warnings issued by health authorities in several countries against the use of benzodiazepines, especially in the elderly, due to cognitive side effects. This is the case in France, where the drug agency in January ANSM criticized treatment times often too long, patients who take these drugs continuously for several years, despite the risk of falling or neuropsychiatric unit incurred .

According ANSM 11.5 million French consume at least once a benzodiazepine in 2012, 7 million to 4.2 million for anxiety and sleep disorders. Consumers had on average 56 years old and nearly two-thirds were women. A third of women over 65 were taking a benzodiazepine for anxiety, and almost one in five sleeping.


To limit the use of sleeping pills in the benzodiazepine family that have a small effect on sleep, the High Authority for Health (HAS), meanwhile called in July to reduce reimbursement by social security 65% in 15% present in the future.

Ebola: French researchers will soon launch a clinical trial in Guinea.

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A team of French researchers (Inserm and Institut Pasteur) and Guinea will launch a clinical trial of an experimental molecule Guinea supposed to stop the replication of Ebola virus. Following authorization Friday, September 5 by WHO (World Health Organization), "before we orienterions molecule developed by the Japanese," says Bernadette Murgue, deputy director of the Institute of Microbiology and Infectious Diseases in Paris. The favipiravir has gone through a phase 3 against resistant to other antiviral flu treatments. It is even already approved in Japan for this indication.

However, "it is still very preliminary," he warns. If the trial is sure to be carried out in Guinea, "we can not give much more information." The only certainty, "although implementation is done in a tighter time than usual, this trial will be conducted in accordance with the rules of good conduct." That's why "we can not reasonably imagine launched before November 2014, he said. Every ethical and regulatory approvals will be obtained and the protocol must pass the ethics committee of Guinea."

"If all goes well, the first preliminary results could be achieved in late March and early April, said Dr. Murgue. Unless promising results immediately or it is not seen very good." Anyway, "if the finest results you want, it takes a little time. "

Safe to say that the French clinical trial protocol, certain aspects seem to be defined. Orally, treatment will follow the same dose as influenza. Patients included not more than fifty years, will certainly adult in the early phase of the disease.

More clinical trials are to be implemented in the coming months and 2 molecules 8 vaccines in countries affected by the epidemic of Ebola. WHO has actually given the green light for clinical evaluations of these experimental treatments. However, did not allow the compassionate use.

"Only the use of convalescent plasma was given to the countries concerned, says Bernadette Murgue. It is to transfuse a patient with the blood of a patient cured, which therefore contains a potentially medium levels greater neutralizing antibodies." done in a therapeutic purpose, this technique can limit replication of the virus. "In any case, this was done in 1995 in the Democratic Republic of Congo (DRC), during another epidemic, she says. An article was published in 1999 after showing encouraging results."

For the first time, researchers were able to determine the structure of a protein while still inside a living cell with an X-ray laser

Thursday, September 11, 2014 / No Comments



For the first time, researchers were able to determine the structure of a protein while still inside a living cell using a laser X-ray This performance, which opens up new possibilities in medicine would certainly have welcomed the pioneers of crystallography which are honored in this year 2014, proclaimed by the United Nations International year of crystallography.

Twenty-eight Nobel Prizes have been awarded for work related to crystallography. The first awards were awarded to pioneers in the field: the German physicist Max von Laue in 1914 (he had shown in 1912 that crystals could diffract X-rays), and in 1915, the father and son Bragg, who showed how to use work of their predecessor to determine the structure of diamond and sodium chloride.


These successes have opened new avenues that led to many discoveries, such as the structures of enzymes and DNA. It is not surprising that the United Nations has declared 2014 International Year of Crystallography.

The X-ray diffraction is limited to the crystals

Physicists, biologists and chemists, among which may be mentioned John Bernal, Linus Pauling, Max Perutz, Dorothy Hodgkin and Aaron Klug, will be interested in the 1930s to determine the structure of certain organic molecules, including proteins and vitamins, using the techniques of X-ray diffraction This work will culminate in 1953 with the discovery of the structure of hemoglobin, for which Max Perutz and John Kendrew will drop out the Nobel prize in Chemistry in 1962, and that of DNA by Watson and Crick, through a diffraction pattern obtained by the British biologist Rosalind Franklin.

Nowadays, the determination of the structure of biological molecules by X-ray diffraction is still a very active field, since it allows the development of all kinds of drugs. One strategy used to understand particular protein structure is to study crystalline form. But this study takes place in vitro, we can not be sure of the actual structure of these proteins when they are still within living cells, ready to participate in biochemical reactions.


To eliminate this bias, researchers have sought to develop a technique of X-ray diffraction that would make measurements in vivo. To this end, they have turned to the X-ray lasers in development for a number of years. An article published in PNAS reported a first success in this direction with the Linac Coherent Laser Light Source of the famous SLAC in California.

An X-ray spied protein in bacteria

The international team of researchers used the LCLS laser was interested in a well-known name of Bacillus thuringiensis (Bt) bacterium, living everywhere in soil and water. It is unusual to synthesize and excrete protein in crystal form that is toxic to insects. Protein crystals are present in the bacteria itself. Experiments were therefore conducted to determine the structure of the crystals inside the cells. To this, a solution containing Bt bacteria was subjected to laser pulses, and over 30,000 figures X-ray diffraction were obtained. They were processed by computer with the mathematical tools of the Fourier analysis, which allowed to reconstruct the 3D structure of proteins.


Successful strategy with the key to the first determination of the structure of a protein in vivo. The results of the experiment showed that at least in this case, there was no difference between the structure of the in vivo and in vitro protein. So it seems that one is indeed able to build a new tool to understand what is going on inside living cells.

Potassium protects postmenopausal women from stroke

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It seems that after menopause, women may reduce their risk of stroke by adopting a diet rich in potassium, according to a study in the United States.

For 11 years, researchers have analyzed the consumption of potassium of more than 90,000 postmenopausal women aged 50 to 79 years, highlighting the impact of stroke. The director of the study published in the journal Stroke from the American Heart Association, Sylvia Wassertheil-Smoller, said previous research has indicated that potassium can lower blood pressure. But they had not yet shown that this mineral may also prevent stroke.


"Our results provide a further incentive for women who eat fruits and vegetables," says Dr. Wassertheil-Smoller today. He added: "Fruits and vegetables are a good source of potassium, and not only the risk of stroke in postmenopausal women, but mortality is reduced."

Bananas and potatoes: Food anti-stroke

At baseline, none of the participants had suffered stroke and mean daily potassium intake was 2,611 mg per woman. Women showed the highest potassium intake saw their risk of stroke by up to 12% compared to those who consumed very little of this mineral. Participants who had normal blood and there was no treatment for hypertension saw its reduced risk by 21%. By contrast, women with hypertension lowered their risk does not attack with increasing potassium intake.

".. Our results show that women should consume more foods rich in potassium, says Dr. Wassertheil-Smoller will not find a lot of potassium in junk food" She also clarified what foods were full of this mineral: potatoes , sweet potatoes, bananas and white beans. However, it also suggests that you consult your doctor your potassium intake, noting in passing that the excess potassium in the blood can be harmful to heart health.


Note also that this study did not consider the sodium intake of the subjects, or the balance between the intake of sodium and potassium, which is important. More research on this topic is needed, the researcher also recommends that should be open to a younger audience.

Blood transfusion named as priority treatment for Ebola

Tuesday, September 9, 2014 / No Comments

Treating Ebola patients with the blood or purified serum of disease survivors should be made a priority in the fight against the ongoing outbreak in West Africa, an expert panel organized by the World Health Organization (WHO) said on 5 September.

The recommendation was the end of a two-day meeting to determine what therapies and experimental Ebola vaccine should be prioritized for clinical development accelerated. WHO estimates that about 3,700 people were infected in West Africa, and about 1,850 died.

Marie-Paule Kieny, Director General of Health Systems and Innovation WHO said that transfusion of whole blood or serum purified Ebola survivors therapy with the greatest potential to be implemented immediately implemented on a large scale in West Africa - in part because the average size of several epidemic potential donors available. The idea is to transfer antibodies to Ebola survivors who are still infected, but there is little information on the effectiveness of such treatment.

Priority, Kieny said, will ensure that donated blood is free of pathogens and other health workers remain safe for transfusion, where they would be exposed to the blood of patients with Ebola. Efforts to establish the infrastructure and training are in place he added.


There is no treatment or vaccine for Ebola has been approved for human use. But on August 11, a group of WHO experts said that it is ethically acceptable to test and use of experimental drugs in the home, provided that all efforts be made to collect scientific data on safety and efficacy. That panel said such measures are justified by the exceptional nature of this epidemic; proved difficult to implement public health measures that ended last Ebola.

Promising candidates

At the meeting of the WHO concluded that on September 5, the experts also recommended testing priority two potential vaccines: a vaccine of chimpanzee adenovirus (ChAd3) developed by the National Institute of Allergy and Infectious Diseases (NIAID) and pharmaceutical giant GlaxoSmithKline, and stomatitis virus recombinant () rVSV vaccine developed by the Public Health Agency of Canada and authorized to genetic Ames, Iowa NewLink gallbladder. Both vaccines and rVSV ChAd3 conferred 100% protection against Ebola virus in animal studies.
The phase I trials of rVSV vaccine will begin this month in the United States, and vaccine trials begin ChAd3 also the United States, the UK, Gambia and Mali. It will test whether vaccines are safe, and if levels are elevated immune response that confers protection against Ebola virus in animals.

Eight hundred doses of rVSV are currently available, the WHO says, and about 15,000 doses of ChAd3 should be ready by the end of the year.

The group convened by WHO also chose to use drugs and testing priority, basing its decision on those who have shown good efficacy and safety in nonhuman primates. ZMapp selected treatments include a cocktail of monoclonal antibodies developed by biopharmaceutical Mapp in San Diego, California, which was shown last week to confer 100% protection in rhesus macaques. On September 2, the Department of Health and Human Services of the United States announced 42.3 million over 18 months for the development and manufacture of drugs.


Oyewale Tomori, a virologist at the University of Redeemer Redemption City, Nigeria, says that efforts to test and distribute new treatments and vaccines should not affect the need to establish baseline measures of public health in the areas of Ebola disaster or providing supportive care for patients. Few patients in endemic areas have access to quality care measures, such as intravenous rehydration, which can significantly reduce mortality. But he said on August 28 that sought $ 490 million to strengthen measures for basic public health and quality of care in treatment centers WHO Ebola.

A low carbohydrate diet is more effective for weight loss and prevention of cardiovascular disease

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A low carbohydrate diet is more effective for weight loss and prevention of cardiovascular disease, according to researchers at Tulane University, Johns Hopkins University and Kaiser Permanente.

A very popular time among whites, the "low carb" diet (low carb) has always had its critics among health professionals, especially since you can consume without looking at the time of use in fatty foods which trying to lose weight. But the situation seems to be changing, especially after a recent study on the subject published in the Annals of Internal Medicine. A group of researchers set out to determine the effects of a low carbohydrate diet in the prevention of cardiovascular disease. This effect was previously unknown, the fewer tests, if any, have been made in a group of quite diverse participants.


For the study, the researchers worked with 148 men and women, half black and half white. All were considered obese according to their body mass index (BMI). Random, researchers assigned each participant is a low carb diet (less than 40 g per day) or a low-fat diet (less than 30% of daily calories from fat). Both groups were subjected to a regular diet followed, and have not set targets for the number of calories consumed per day, or about physical activity. However, the researchers note that the level of physical activity was quite similar between the two groups does not affect the results.

Less sugar is 3.5 kg less fat

Having data stored in other cardiovascular risk factors and weight at the start of the study, the researchers invited participants at regular intervals (3, 6 and 12 months) to take action and check the ongoing maintenance regime. The researchers extracted data from participants who dropped out before the end of 12 months. Finally, the low-fat diet was followed by 60 participants (82%). Similar to the low-carb diet, followed by the full year by 59 participants (79%) score.

However, among the remaining participants, those who avoided carbohydrates lost 3.5 kg more, on average, compared with participants in the low-fat diet. The former also showed significant decreases in body fat index and other risk factors for cardiovascular disease. Furthermore, the blood levels of certain lipids may indicate an increased risk of cardiovascular disease was lower for the "low carb" group.


More curious finding of the study: the reduction of waist circumference was higher among participants dietary fat during controls at 3 months and 6 months, although this difference is the level at end of study.


Ebola:national security in West Africa is threatened by Ebola

Thursday, September 4, 2014 / No Comments
The virus is not suppressed due to the absence of a global effort to implement emergency measures for public health.
The Ebola outbreak rooted in West Africa has become a real threat to the stability and security of society in the region, the best American Centers for Disease Control and Prevention Diseases official said today, after his return yesterday a trip there.

Failure to comply with the spread of the Ebola virus is emphasizing infrastructure of the countries affected by the disease that still will continue to provide basic health and safety and promote the business of the routine. Fear of its spread also hinders attention to other diseases and can put more and more the stability of neighboring countries at risk, said CDC Director Tom Frieden during a press conference today. "This is a problem for the world and the world needs to respond," he said. The spread of the epidemic in Guinea, Sierra Leone, Liberia and Nigeria to include Senegal. Fortunately, a small separate in the Democratic Republic of Congo Ebola outbreak does not appear to be related to the case of West Africa.


Meanwhile, Ebola also hinders all other medical care because health workers are afraid to go to work, Frieden said. Paradoxically, attempts to help pack the virus by canceling flights to the countries where the virus is actually making it more difficult to send staff and essential supplies, he said. "I could not overstate the need for urgent action," he said. "The window of opportunity very firm."

CDC calls for more medical supplies, technical experts in the management of health care and in a comprehensive and coordinated approach to the epidemic. Currently, there is still enough beds for patients, not enough to come to help the case of the string data. Surveillance and monitoring of those who were potentially exposed to the virus are still insufficient. Frieden urged people with experience in health care to volunteer with organizations like Doctors Without Borders that have the expertise to assist in response experience. These efforts are not without risk. SIM USA today announced another American missionary doctor has tested positive for the Ebola virus. This doctor was not treated Ebola patients, but patients treated obstetric center in Monrovia, Liberia.

In the coming weeks, to help strengthen the region's response, the World Health Organization has established a call for $ 490 million dollars. And this week, clinical trials of a vaccine candidate against Ebola National Institutes of Health will start. An experimental drug called ZMapp also shows promise to help cure Ebola in monkeys, but has not been tested in human clinical trials. But in the meantime, every day of the disease is not controlled, it can be harder to quit than the scale of the epidemic grows, Frieden said. It is also possible that genetic mutations that the virus accumulates over time could make it fatal or easily transmissible between humans.

The epicenter of the epidemic, the wooded area at the intersection of the porous borders of these countries, home to about one million people, Frieden said. Improve access to programs of existing health care in their fight against malaria could help reduce the load and increase the confidence level of the population, but it will be a slow process. Currently, he said, "We need a win-win" policy, where we will not look back and say we should have done more.

The EGFR Macrophage promotes liver cancer

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Hepatocellular carcinoma (HCC) is a common cancer with limited treatment options and poor prognosis. Tumorigenesis has been associated with chronic inflammation mediated by macrophages and different signaling pathways, including the receptor for epidermal growth factor (EGFR) track. The precise role of EGFR in HCC is unknown, and EGFR inhibitors have shown disappointing clinical results. Here, we found that EGFR is expressed in macrophages in both human liver and HCC in a
 mouse model of HCC. Mice lacking EGFR show in hepatocarcinogenesis alteration macrophages, whereas mice lacking hepatocyte EGFR develop HCC more unexpectedly due to increased damage and compensatory proliferation of hepatocytes. Mechanically, interleukin-1, upon stimulation, the EGFR necessary liver macrophages to induce transcription of the interleukin-6, which triggers the proliferation of hepatocytes and HCC. Importantly, the presence of EGFR-positive hepatic macrophages in patients with HCC is associated with poor survival. This study shows a mechanism of tumor promotion not EGFR in tumor cells, which could lead to more effective strategies of drug accuracy.

Area of Brain Responsible for Exercise Motivation Discovered

Tuesday, September 2, 2014 / No Comments
Scientists at the Institute of Seattle Children's Research found that the area median dorsal habenula in the brain controls the desire to exercise in mice may help researchers develop more specific and effective treatments for depression.
Scientists at the Institute of Seattle Children's Research have discovered a brain region that could control a person's motivation to exercise and participate in other rewarding activities - which could lead to better treatments for depression.

Dr. Eric Turner, senior fellow at the Institute for Research on the Comprehensive Brain Child of Seattle, in collaboration with lead author Dr. Yun-Wei (Toni) Hsu, found that a small region of the brain - the dorsal habenula internal - control the desire to exercise in mice. The structure of the habenula is similar in humans and rodents and basic functions of regulation and mood motivation may be the same in all species.

Exercise is one of the most effective non-pharmacological therapies for depression. Determine that such a specific area of ​​the brain may be responsible for the motivation to exercise can help researchers develop more targeted, effective treatments for depression.

"Changes in physical activity and the inability to enjoy rewarding or pleasurable experiences are two features of major depression," Turner said. "But the pathways responsible for the brain fitness motivation is not well understood. Now we can find ways to manipulate the activity in this specific area of the brain without affecting other brain activity."

The study by Dr. Turner, "The role of the dorsal medial habenula in the regulation of voluntary activity, motor function, hedonic state, and primary reinforcement", was released by the Journal of Neuroscience today and funded by the National Institute of Mental Health and the National Institute on Drug Abuse. Mouse models used to study have been genetically modified to block signals in the dorsal medial habenula. In the first part of the study, the team of Dr. Turner has worked with Dr. Horacio de la Iglesia, a professor of biology at the University of Washington, to show that, compared to typical mice, which would run on the wheel the year, the mice were genetically engineered lethargic and run much less. Mice GM Turner also lost their preference for sweet drinking water.

"Without a dorsal medial habenula operation, the mouse has become couch potatoes," Turner said. "They were physically able to run, but they seemed motivated to do so."

In a second group of mice, the team of Dr. Turner activates the dorsal medial habenula using optogenetics - precision laser technology developed in collaboration with the Allen Institute for Brain Science. The mouse can "choose" to activate this brain area respond by turning the wheel with his paws. Mice sought spin the wheel, which stimulated the dorsal medial habenula, showing that this brain region is linked to reward behavior.

Previous studies have attributed habenula many different functions, but the technology was not advanced enough to determine the functions of the various sections of this region of the brain, including the dorsal medial habenula.

"Traditional methods of stimulation could not isolate this part of the brain," Turner said. "But the technology at the Institute of Seattle Children's Research made ​​discoveries like this possible."

As a professor at the University Department of Psychiatry and Behavioral Sciences Washington, Dr. Turner treats depression and hope that this research will make a difference in the lives of future patients.

"Working in mental health can be frustrating," Turner said. "We have made great progress in developing new treatments. Hopefully we can learn more about how it works the more we can help people with all types of mental illness in the brain."


sound waves to classify cells

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Researchers from MIT and Carnegie Mellon University have developed a new technique for cell sorting using sound waves. Applications in the field of diagnostics are possible
For research or medical diagnostics, it is often necessary to sort the cells of a fluid in accordance with different parameters. Currently, existing techniques require labeling the cells with chemicals or exposed to mechanical forces that can damage them.

That's why researchers are trying to develop milder methods that best preserve the cells. Using sound waves is an interesting alternative, as Dao Ming, a researcher in the department of materials science and engineering at MIT explains, "the sound pressure is very light and very inferior in terms of resistance and the cell disruption. is a smoother way to remove cells and artificial no need to dial ".


To sort the cells using acoustic waves, scientists first build devices that were issued in two waves on each side of a microchannel. For assembly, the two are combined to form an acoustic standing wave parallel to the direction of the fluid cell surface. Like any standing wave has pressure nodes. When cells are one of them, that are thrust toward the side of the channel. The distance of movement of the cell depends on the cell size and other properties such as compressibility. But this method was ineffective, hence the need for improvements.

Improved efficiency through the inclination of the waves

In an article published in PNAS, the researchers explain that the disadvantage of the method used above was that the cells were not pushed aside in short distances. The new tool developed overcomes this obstacle by the inclination of the acoustic waves with respect to the direction of flow: for example, a cell may find several nodes pressure passes through the channel. Each time, the more pressure guides, from the center, which facilitates the capture of cells of different sizes.

This device significantly enhances the efficiency and sensitivity of acoustic separation techniques: the researchers were able to separate polystyrene beads from 2 to 10 microns with an efficiency of 99%, and the grains of 7.3 and 9.9 microns with a 97% efficiency. They also conducted a computer simulation to predict the trajectory of the cells in the channel based on their characteristics and the angle of the acoustic waves: this allowed them to develop a device capable of separating different types of cells.

Many applications can be envisaged, particularly in the field of diagnosis. Therefore, such a device could detect rare circulating in the blood, which indicate whether a primary cancer generates m. Another possible application: separation of blood cells (red cells, white cells, platelets).

Fight depression elderly subjects with video games?

Friday, August 29, 2014 / No Comments

Intellectual stimulation through computer games could in some older people with severe depression, do as well or better than drugs as a study published in the journal Nature Communications suggests.

Depression affects many elderly and if psychotherapy and antidepressants conventional medication are effective for some, for many, these treatments have little effect on the disease, say the authors of a paper in Nature Communications highlighting the need for treatment more active in geriatrics. "Antidepressant medications are often slow to act and often incomplete and unstable results. Remissions occur only in one third of patients," they write.


These Americans and Chinese experts have created computerized cognitive training programs and tested in eleven individuals of 60-89 years, resistant to treatment, to improve their learning skills and memory. They compared their results with those obtained in another study of 33 adults treated with the antidepressant major reference, escitalopram (brand names: Seroplex, Cipralex or Lexapro), instead of computer-assisted therapy.

Depressions healed in 4 weeks
The results suggest that these brain training exercises were equally effective in reducing symptoms of depression escitalopram, faster: in four weeks instead of two, according to the authors. "72% [of patients] had a complete remission of depression," says Sarah Morimoto Geriatric Psychiatric Institute in New York, co-author of the study. A full clinical study with a larger number of patients would be needed to confirm these findings, the researchers admit, but hope that their study will stimulate more research on alternative therapies for depression resulted.

Programs were developed to test the theory that brain aging can be fought through intense practice of this type of game, to recover the function of learning and memory loss and improve decision-making in order to improve the state of depression. Previous research has shown that low levels of certain intellectual functions also led to a poor response to antidepressants.

Plants Use “Language” to Communicate

Wednesday, August 27, 2014 / No Comments
A new study by Virginia Tech shows that plants can use a newly discovered to communicate with each other, opening the door to a new field of science that explores how plants communicate with each other on a molecular level molecular language.
A scientist at Virginia Tech has discovered potentially new form of communication of the plant, allowing them to share an extraordinary amount of genetic information between themselves.

The discovery by Jim Westwood, professor of plant pathology, physiology and weed science in the College of Agriculture and Life Sciences, opens the door to a new field of science that explores how plants communicate with each other at a molecular level. It also gives scientists new insight into how to fight parasitic weeds that wreak havoc on food crops in some of the poorest regions of the world.

Their findings were published on August 15 in the journal Science.

"The discovery of this new form of communication between agencies shows that this happens much more than what you have already done," Westwood, which is affiliated with the Institute of Life Sciences Fralin researcher said. "Now that we have found to share this information, the next question is," What exactly did you say the other?

Professor Jim Westwood has discovered that parasitic plants and their hosts have extensive communications with each other and exchange vast amounts of information. He used dodder and tomato plants, shown in this time-lapse video, for his experiment that measured the exchange of mRNA between species.
Westwood examined the relationship between a parasitic plant, dodder, and two host plants, Arabidopsis and tomatoes. In order to suck the moisture and nutrients out the host plants, dodder uses an appendage called a haustorium to penetrate the plant. Westwood previously broke new ground when he found that during this parasitic interaction, there is a transport of RNA between the two species. RNA translates information passed down from DNA, which is an organism’s blueprint.
His new work expands this scope of this exchange and examines the mRNA, or messenger RNA, which sends messages within cells telling them which actions to take, such as which proteins to code. It was thought that mRNA was very fragile and short-lived, so transferring it between species was unimaginable.
But Westwood found that during this parasitic relationship, thousands upon thousands of mRNA molecules were being exchanged between both plants, creating this open dialogue between the species that allows them to freely communicate.
Through this exchange, the parasitic plants may be dictating what the host plant should do, such as lowering its defenses so that the parasitic plant can more easily attack it. Westwood’s next project is aimed at finding out exactly what the mRNA are saying. His work is sponsored by the National Science Foundation.
Using this newfound information, scientists can now examine if other organisms such a bacteria and fungi also exchange information in a similar fashion. His finding could also help solve issues of food scarcity.
“Parasitic plants such as witchweed and broomrape are serious problems for legumes and other crops that help feed some of the poorest regions in Africa and elsewhere,” said Julie Scholes, a professor at the University of Sheffield, U.K., who is familiar with Westwood’s work but was not part of this project. “In addition to shedding new light on host-parasite communication, Westwood’s findings have exciting implications for the design of novel control strategies based on disrupting the mRNA information that the parasite uses to reprogram the host.”
Westwood said that while his finding is fascinating, how this is applied will be equally as interesting.
“The beauty of this discovery is that this mRNA could be the Achilles heel for parasites,” Westwood said. “This is all really exciting because there are so many potential implications surrounding this new information.”
Nationally ranked among the top research institutions of its kind, Virginia Tech’s College of Agriculture and Life Sciences focuses on the science and business of living systems through learning, discovery, and engagement. The college’s comprehensive curriculum gives more than 3,100 students in a dozen academic departments a balanced education that ranges from food and fiber production to economics to human health. Students learn from the world’s leading agricultural scientists, who bring the latest science and technology into the classroom.

Life expectancy has she reached its limits?

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In a study published in the American Journal of Gerontology, researchers at the Institute of Biomedical Research and Sports Epidemiology (IRMES) say their discovery strengthens the case for a limited period of life. The researchers studied all 1,205 global supercentenarians (125 men and 1080 women) whose date of birth was confirmed and died between 1899 and 2013 also reviewed the 19,012 athletes at the Olympic Games since 1896 and died before the end of last year, insofar usually outlive their average counterparts. The lead researcher, Juliana Antero-Jacquemin was a kind of plateau in Olympic athletes 80-85 years, while among supercentenarians ceiling was set around 115 years.




Scientists Confirm Cellular Basis for Memory by Implanting and Erasing Fear in Rats

Monday, August 25, 2014 / No Comments





By controlling the brain cells of rats that had been genetically modified to respond to light, the researchers were able to create memories of terrible events that never took place - and to erase those memories again. Credit: Sadegh Sina Nabavi and Alizadeh

In a recently published study, scientists from the University of California demonstrate the ability to selectively remove and re-predictable memory by stimulating the nerves in the brain at frequencies which are known to weaken and strengthen connections between nerve cells.

Researchers at the University of California, School of Medicine, San Diego have cleared and reactivated memories in rats, profoundly changing the reaction of the animals to past events.

The study, published in the edition of June 1 advanced online edition of Nature, is the first to demonstrate the ability to selectively remove a memory and reactivate predictable by stimulating the nerves in the brain at frequencies that are known to weaken and strengthen the links between nerve cells, synapses.

"We can form a memory, clear the memory and can reactivate at will by applying a stimulus that strengthens or weakens the selective synaptic connections," said Roberto Malinow, MD, PhD, professor of neuroscience and lead author of the study.


Scientists optically stimulated a group of nerves in the brain of a rat that had been genetically modified to be sensitive to light, and at the same time gives an electric shock to the foot of the animal. The rats quickly learned to associate the stimulation of the optic nerve with pain and fear behaviors displayed when these nerves are stimulated.

Analyses showed signs of chemical changes in nerve synapses optically stimulated synaptic strengthening.

In the next step of the experiment, the research team has demonstrated the ability to reduce the circuit by stimulating the same nerve with a memory erase, low burst optical frequency. These rats respond more responded to stimulation of the original nerve with fear, suggesting the association of pain memory had been erased.

In what might be the most surprising finding of the study, scientists found that they could revive the lost re-stimulate the same nerves with a train of optical pulses in memory of memory training high frequency. These rats repaired once again responded to the stimulus of the original fear, even if they had not had their feet re-shock.

"We can not force an animal to fear and then do not be afraid and fear again by stimulating nerves at frequencies that strengthen or weaken synapses," said Sadeq Nabavi, a postdoctoral researcher in the laboratory Malinow and lead author of the study .


As for potential clinical applications, Malinow, which occupies the Shiley Chair in research on Alzheimer's disease in honor of Dr. Leon Thal, said the beta amyloid peptide that accumulates in the brains of people with the disease Alzheimer weakens the synaptic connections in the same way that the low frequency stimulation in rats erase memories. "Since our work shows that we can reverse the processes that weaken synapses, which could offset some of the effects of beta-amyloid protein in patients with Alzheimer's disease," he said.