Promising target for HIV treatment identified

Like a slumbering dragon, HIV can lay dormant in a person's cells for years, evading medical treatments only to wake up and strike at a later time, quickly replicating itself and destroying the immune system.

Now, scientists at the Salk Institute for Biological Studies have uncovered a new protein that participates in active HIV replication.

The protein, called Ssu72, is part of a switch used to awaken HIV-1 (the most common type of HIV) from its slumber.

The team began by identifying a list of 50 or so proteins that interact with a well-known protein HIV creates called Tat.

"The virus cannot live without Tat," said Katherine Jones, Salk professor in the Regulatory Biology Laboratory and senior author of the study.

Tat acts as a lookout in the cell for the virus, telling the virus when the cellular environment is favourable for its replication.

When the environment is right, Tat kicks off the virus' transcription, the process by which HIV reads and replicates its building blocks (RNA) to spread throughout the body.

One of the proteins on the list that caught Jones' eye was Ssu72 (a phosphatase).

This enzyme had been shown in yeast to affect the transcription machinery. Her team found that Ssu72 binds directly to Tat and not only begins the transcription process, but also creates a feedback loop to ramp up the process.

"Tat is like an engine for HIV replication and Ssu72 revs up the engine," said Lirong Zhang, one of the first authors.

"If we target this interaction between Ssu72 and Tat, we may be able to stop the replication of HIV," said Zhang.

The team found that Ssu72 is not required for making RNA for most host cell genes in the way it is used by HIV, making it a potentially promising target for drug therapy.

"Many proteins that Tat interacts with are essential for normal cellular transcription so those can't be targeted unless you want to kill normal cells," said co-first author Yupeng Chen, a Salk researcher.

"Ssu72 seems to be different - at least in the way it is used by HIV," said Chen.

The study was published in the journal Genes and Development.

Walnuts help prevent Alzheimer disease

The study was published in the Journal of Alzheimer's Disease.

Having a walnut-enriched diet every day may help reduce the risk, delay the onset, slow the progression of, or prevent Alzheimer's disease all together, found a study led by an Indian-origin researcher.

"study adds to the growing body of research that demonstrates the protective effects of walnuts on cognitive functioning," said Abha Chauhan from the New York State Institute for Basic Research in Developmental Disabilities (IBR).

The research group examined the effects of dietary supplementation on mice with six percent and nine percent walnuts, that is equivalent to one ounce (28.3 gram) and 1.5 ounces (42.5 gram) per day, respectively.

The researchers found significant improvement in learning skills, memory, reducing anxiety and motor development in mice fed a walnut-enriched diet.

Oxidative stress and inflammation are prominent features in the disease.

The high antioxidant content of walnuts (3.7 mmol/ounce) may have been a contributing factor in protecting the mouse's brain from the degeneration typically seen in Alzheimer's disease, the researchers suggested.

This research stemmed from a previous cell culture study led by Chauhan that highlighted the protective effects of walnut extract against the oxidative damage caused by amyloid beta protein.

"These findings are very promising and could help lay the groundwork for future human studies on walnuts and Alzheimer's disease - a disease for which there is no known cure," Chauhan added.

The protein is the major component of amyloid plaques that form in the brains of those with Alzheimer's disease.

Artificial sweeteners may alters body blood sugar controls

Scientists have found that artificial sweeteners alter the microbiome, the population of bacteria that is in the digestive system.

Artificial sweeteners may disrupt the body’s ability to regulate blood sugar, causing metabolic changes that can be a precursor to diabetes, researchers are reporting.

That is “the very same condition that we often aim to prevent” by consuming sweeteners instead of sugar, said Dr Eran Elinav, an immunologist at the Weizmann Institute of Science in Israel, at a news conference to discuss the findings.

The scientists performed a multitude of experiments, mostly on mice, to back up their assertion that the sweeteners alter the microbiome, the population of bacteria that is in the digestive system.

The different mix of microbes, the researchers contend, changes the metabolism of glucose, causing levels to rise higher after eating and to decline more slowly than they would.

The findings by Dr Elinav and his collaborators in Israel, including Eran Segal, a professor of computer science and applied mathematics at Weizmann, were published in September by the journal Nature.

Cathryn R Nagler, a professor of pathology at the University of Chicago who was not involved with the research but did write an accompanying commentary in Nature, called the results “very compelling.”

She noted that many conditions, including obesity and diabetes, had been linked to changes in the microbiome. “What the study suggests,” she said, “is we should step back and reassess our extensive use of artificial sweeteners.”

Previous studies on the health effects of artificial sweeteners have come to conflicting and confusing findings. Some found that they were associated with weight loss; others found the exact opposite, that people who drank diet soda actually weighed more.

Some found a correlation between artificial sweeteners and diabetes, but those findings were not entirely convincing: Those who switch to the products may already be overweight and prone to the disease.

While acknowledging that it is too early for broad or definitive conclusions, Dr Elinav said he had already changed his own behavior.

“I’ve consumed huge amounts of coffee, and extensively used sweeteners, thinking like many other people that they are at least not harmful to me and perhaps even beneficial,” he said. “Given the surprising results that we got in our study, I made a personal preference to stop using them.

“We don’t think the body of evidence that we present in humans is sufficient to change the current recommendations,” he continued. “But I would hope it would provoke a healthy discussion.”

In the initial set of experiments, the scientists added saccharin (the sweetener in the pink packets of Sweet’N

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Lung cancer can stay hidden for over 20 years

A new U.K. study reveals that lung cancer can remain inactive for almost 20 years before suddenly appearing as an aggressive form of the disease.
Lung cancers can lie dormant for over 20 years before suddenly turning into an aggressive form of the disease, according to a study published Thursday in the U.S. journal Science.

Lung cancer is known as the leading type of deadly cancer among U.S. men and women, and the second most common cancer diagnosed in the U.S. Cigarette smoking is listed as the leading cause of lung cancer, which can also be caused by using other types of tobacco. The American Cancer Society estimates that in the United States, for the year 2014, there will be about 224,210 new cases of lung cancer and nearly 159,260 deaths from it. This disease accounts for 27 percent of all cancer deaths.

The latest study, conducted by the Cancer Research UK's London Research Institute and the UCL Cancer Institute, found that lung cancer can remain hidden for over 20 years. This was based on the study conducted on lung cancers from seven patients that included smokers, ex-smokers and never smokers.

The researchers hoped this study will help improve early detection of the disease.

Professor Nic Jones, Cancer Research UK's chief scientist, said: "This fascinating research highlights the need to find better ways to detect lung cancer earlier when it's still following just one evolutionary path. If we can nip the disease in the bud and treat it before it has started travelling down different evolutionary routes we could make a real difference in helping more people survive the disease..."

It was noticed that after the first genetic mistake that triggered cancer, it can continue to exist undetected for several years until the novel additional defect triggers the rapid growth of the disease. It is during this expansion a sudden gush of different genetic faults that appear in separate region of the tumors. Each of the different sections comes from various paths indicating that every part of the tumor is genetically unique.

This study shows the need for advanced method to detect the disease earlier. Nearly two-thirds of the patients are being diagnosed with advanced form of cancers during which treatment is not successful. Based on this finding, the researchers hope for some improvement in the early detection of the disease.

Study author Professor Charles Swanton, at Cancer Research UK's London Research Institute and the UCL Cancer Institute, said: "Survival from lung cancer remains devastatingly low with many new targeted treatments making a limited impact on the disease. By understanding how it develops we've opened up the disease's evolutionary rule book in the hope that we can start to predict its next steps."

The finding was documented in Science today.

Insomnia related to sleep quality and not duration

Insomnia among older adults may be tied to sleep quality, and not sleep duration, according to a new study.

Researchers at the University of Chicago found that sleep problems may stem from the quality of rest and other health concerns more than the overall amount of sleep that patients get.

An estimated 30 per cent of adults report having some symptoms of insomnia, which includes difficulty falling asleep, staying asleep or waking up too early and then not feeling well rested during the daytime, researchers said.

The study used data from 727 participants in the National Social Life, Health and Aging Project in the US who were randomly invited to participate in an "Activity and Sleep Study."

The activity and sleep study had two components: a self-administered sleep booklet, which included questions about the person's sleep experience, (eg, "how often do you feel really rested when you wake up in the morning?") and 72-hours of wrist actigraphy, which is a wristwatch-like sensor that monitors sleep patterns and movements.

The actigraph measurements showed that most of the older adults got sufficient amounts of sleep.

Even though reported sleep problems are common among older individuals, according to the survey only about 13 per cent of older adults in the study said that they rarely or never feel rested when waking up in the morning.

About 12 per cent reported often having trouble falling asleep, 30 per cent indicated they regularly had problems with waking up during the night and 13 per cent reported problems with waking up too early and not being able to fall asleep again most of the time.

The actigraph provided data that showed the average duration of sleep period among the study participants was 7.9 hours and the average total sleep time was 7.25 hours.

Linda Waite, an author on the study, said this indicates that the majority of older adults are getting the recommended amount of sleep and usually not having common sleep problems.

Researchers also found that respondents who reported waking up more frequently during the night had more total sleep time.

"This suggests that a question about feeling rested may tap into other aspects of older adults' everyday health or psychological experience," said Waite.

"Our findings suggest that reports of what seem like specific sleep problems from survey questions may be more accurately viewed as indicators of general problems or dissatisfaction with sleep that may