Category: Health

{New breakthrough in neuroscience: Self confidence can be directly amplified in the brain.}

Self-confidence is an essential quality to succeed in the world, such as in business environments, politics or many other aspects of our everyday life. Furthermore, confidence is an important aspect in mental illnesses such as depression and Alzheimer’s disease, where the condition is often further complicated by patients thinking negatively of their own capacities. Recent advances in neuroscience have highlighted the plasticity of the brain, indicating it is malleable even later in life.

The international team developed a state-of-the-art method to read and then amplify a high confidence state using a new technique called ‘Decoded Neurofeedback’. This technique used brain scanning to monitor and detect the occurrence of specific complex patterns of activity corresponding to high confidence states, while participants performed a simple perceptual task. In the training sessions, whenever the pattern of high confidence was detected, participants received a small monetary reward. This experiment allowed researchers to directly boost one’s own confidence unconsciously, i.e. participants were unaware that such manipulation took place. Importantly, the effect could be reversed, as confidence could also be decreased.

Dr. Mitsuo Kawato, Director of the Computational Neuroscience Laboratories at ATR, Kyoto, and one of the authors on the study, has pioneered this state-of-the-art technology. He explained the process:

“How is confidence represented in the brain? Although this is a very complex question, we used approaches drawn from artificial intelligence (AI) to find specific patterns in the brain that could reliably tell us when a participant was in a high or low confidence state. The core challenge was then to use this information in real-time, to make the occurrence of a confident state more likely to happen in the future.”

Dr. Aurelio Cortese, of the Advanced Telecommunications Research Institute International, Kyoto, led the research:

“Surprisingly, by continuously pairing the occurrence of the highly confident state with a reward — a small amount of money — in real-time, we were able to do just that: when participants had to rate their confidence in the perceptual task at the end of the training, their were consistently more confident.”

Dr. Hakwan Lau, Associate Professor in the UCLA Psychology Department, was the senior author on the study and an expert in confidence and metacognition:

“Crucially, in this study confidence was measured quantitatively via rigorous psychophysics, making sure the effects were not just a change of mood or simple reporting strategy. Such changes in confidence took place even though the participants performed the relevant task at the same performance level.”

The sample size was relatively small (17 people), but is in line with basic science investigations of similar kinds. The team is currently working on the development of potential new clinical treatment for patients with various psychiatric conditions.

NOTE: The team, in a different study led by co-author Dr. Ai Koizumi, has indeed already discovered a new way to unconsciously erase fear memories, reprogramming the brain to overcome fear. The study was recently published in the inaugural edition of Nature Human Behavior on November 21st, and opens the potential for radical new treatments of conditions such as post-traumatic-stress-disorder (PTSD) and phobias.

{Their offices are simple wooden seats, called Friendship Benches, located in the grounds of health clinics around Harare and other major cities in Zimbabwe.}

The practitioners are lay health workers known as community “Grandmothers,” trained to listen to and support patients living with anxiety, depression and other common mental disorders.

But the impact, measured in a ground-breaking study, shows that this innovative approach holds the potential to significantly improve the lives of millions of people with moderate and severe mental health problems in countries where access to treatment is limited or nonexistent.

Funded by the Government of Canada through Grand Challenges Canada, the randomised controlled trial was conducted by the University of Zimbabwe, the London School of Hygiene & Tropical Medicine and King’s College London. The study is published today in JAMA.

Six months after undergoing six weekly “problem solving therapy” sessions on the Friendship Benches, participants showed significant differences in severity of depression, anxiety, and suicidal thoughts based on locally validated questionnaires for depression and anxiety: the Shona Symptom Questionnaire (SSQ), the Patient Health Questionnaire (PHQ) and the Generalised Anxiety Disorder scale (GAD). The results were striking.

Patients with depression or anxiety who received problem-solving therapy through the Friendship Bench were more than three times less likely to have symptoms of depression after six months, compared to patients who received standard care. They were also four times less likely to have anxiety symptoms and five times less likely to have suicidal thoughts than the control group after follow-up.

50 percent of patients who received standard care still had symptoms of depression compared to 14 percent who received Friendship Bench (based on PHQ). 48 percent of patients who received standard care still had symptoms of anxiety compared to 12 percent who received Friendship Bench (based on the GAD), and 12 percent of patients who received standard care still had suicidal thoughts compared to 2 percent who received Friendship Bench (based on SSQ).

The Friendship Bench intervention was also shown to be well suited to improve health outcomes among highly vulnerable individuals. 86 percent of the study’s participants were women, over 40 percent were HIV positive, and 70 percent had experienced domestic violence or physical illness.

Lead author of the study Dr. Dixon Chibanda, a consultant psychiatrist in Harare, co-founded the Friendship Bench network in response to the appalling shortage of evidence-based treatment for people with mental disorders in Zimbabwe, a problem common throughout Africa.

While about 25 percent of the country’s primary care patients suffer from depression, anxiety and other common mental disorders, Zimbabwe (population 15 million) has only 10 psychiatrists and 15 clinical psychologists.

“Common mental disorders impose a huge burden on all countries of sub-Saharan Africa,” says Dr. Chibanda. “Developed over 20 years of community research, the Friendship Bench empowers people to achieve a greater sense of coping and control over their lives by teaching them a structured way to identify problems and find workable solutions.”

With CDN $1 million in funding from Grand Challenges Canada earlier this year, the Friendship Bench has since been scaled to 72 clinics in the cities of Harare, Gweru and Chitungwiza (total population 1.8 million). Through collaborating with a Médecins Sans Frontières psychiatric program in Zimbabwe, the Friendship Bench is working to create the largest comprehensive mental health program in sub-Saharan Africa.

{{To date, over 27,500 people have accessed treatment}}

“In developing countries, nearly 90 percent of people with mental disorders are unable to access any treatment,” says Dr. Peter A. Singer, Chief Executive Officer of Grand Challenges Canada. “We need innovations like the Friendship Bench to flip the gap and go from 10 percent of people receiving treatment, to 90 percent of people receiving treatment.”

“In many parts of Africa, if you are poor and mentally ill, your chances of getting adequate treatment are close to zero,” says Dr. Karlee Silver, Vice President Programs at Grand Challenges Canada. “In Zimbabwe, that’s changing thanks to the Friendship Bench, the first project with the potential to make mental health care accessible to an entire African nation.”

In 2017, the team will focus on expanding the model to reach other vulnerable populations, including youth and refugees. In partnership with the Swedish NGO SolidarMed, the team intends to expand implementation of this model in Masvingo province and subsequently in the refugee centres of the eastern highlands on the border with Mozambique.

“The Friendship Bench team, working with the Zimbabwe Ministry of Health, has been able to substantially scale up services for some of the most deprived people in the community,” says Dr. Shekhar Saxena, Director of Mental Health and Substance Abuse at the World Health Organization. “By supporting the uptake of mental health innovations like the Friendship Bench, Canada is helping to turn the tide in the global mental health challenge.”

The study, published today in JAMA and supported by Grand Challenges Canada, was conducted from September 2014 to June 2015, and involved:

Identifying participants at 24 primary care clinics in Harare, divided into an intervention group (287 participants) and a control group (286). Total participants: 573.
Participants were all at least 18 years old (median age 33);
All had been assessed at 9 or higher on a 14-level “Shona Symptoms Questionnaire” (SSQ-14), an indigenous measure of common mental disorders in Zimbabwe’s Shona language . Changes in depression were measured using the PHQ-9 scale.
Excluded were patients with suicidal intent (those who were clinically depressed with suicidal thoughts and a plan for suicide), end-stage AIDS, were currently in psychiatric care, were pregnant or up to 3 months post-partum, presented with current psychosis, intoxication, and/or dementia (such patients were referred to a higher level clinic in Harare).
The control group received standard care (nurse assessment, brief support counselling, medication, referral to see a clinical psychologist and/or a psychiatrist, and Fluoxetine if warranted) plus education on common mental disorders.
Intervention group participants met on a wooden bench on the grounds of municipal clinics with trained, supervised lay health workers, popularly known as “grandmothers,” (median age 53) who provided problem solving therapy with three components — “opening up the mind, uplifting the individual, and further strengthening.”

The 45-minute sessions took place weekly for six weeks, with an optional 6-session group support program available

The “grandmothers” used mobile phones and tablets to link to specialist support. They also used a cloud-based platform that integrated the Friendship Bench project’s training, screening, patient referral and follow-up components

After three individual sessions, participants were invited to join a peer-led group called Circle Kubatana Tose, or “holding hands together,” which provided support from men and women who had benefitted from the Friendship Bench earlier. At these weekly meetings, people shared personal experiences while crocheting purses made from recycled plastic materials, the latter being an income-generating skill for participants.

{Marijuana use increased and the drug’s perceived harmfulness decreased among eighth- and 10th-graders in Washington after marijuana was legalized for recreational use by adults but there was no change among 12th-graders or among students in the three grades in Colorado after legalization for adults there, according to a new study published online by JAMA Pediatrics.}

Washington and Colorado became the first two states to legalize recreational use of marijuana for adults in 2012, followed by handful of other states since. The potential effect of legalizing marijuana for recreational use has been a topic of considerable debate.

Magdalena Cerdá, Dr.P.H., M.P.H., of the University of California Davis School of Medicine, Sacramento, and coauthors examined the association between legalizing recreational use of marijuana for adults in the two states and changes in perception of harmfulness and self-reported adolescent marijuana use before and after legalization.

The authors used data from nearly 254,000 students in the eighth, 10th and 12th grades who took part in a national survey of students. They compared changes prior to recreational marijuana legalization (2010-2012) with post-legalization (2013-2015) and with trends in other states that did not legalize recreational marijuana.

In Washington among eighth- and 10th-graders, perceived harmfulness declined 14.2 percent and 16.1 percent, respectively, while marijuana use increased 2.0 percent and 4.1 percent, respectively. Among states that did not legalize recreational marijuana use, perceived harmfulness decreased 4.9 percent and 7.2 percent among eighth- and 10th-graders, respectively, and marijuana use decreased by 1.3 percent and 0.9 percent, respectively, according to the results.

No changes were seen in perceived harmfulness or marijuana use among Washington 12th-grades or students in the three grades in Colorado, for which researchers offer several explanations in their article.

The authors also offer several potential explanations for the increase in marijuana use among eighth- and 10th-graders in Washington, including that legalization may have increased availability through third-party purchases. Limitations of this study include that it relied on self-reported marijuana use. Also, analysis specific to the states of Washington and Colorado may not be generalizable to the rest of the United States.

“Although further data will be needed to definitively address the question of whether legalizing marijuana use for recreational purposes among adults influences adolescent use, and although these influences may differ across different legalization models, a cautious interpretation of the findings suggests investment in evidence-based adolescent substance use prevention programs in any additional states that may legalize recreational marijuana use,” the article concludes.

{Mrs. M would never forget that day. She was walking along a busy road next to the vegetable market when two goons zipped past on a bike. One man’s hand shot out and grabbed the chain around her neck. The next instant, she had stumbled to her knees, and was dragged along in the wake of the bike. Thankfully, the chain snapped, and she got away with a mildly bruised neck. Though dazed by the incident, Mrs. M was fine until a week after the incident.}

{{Then, the nightmares began.
}}

She would struggle and yell and fight in her sleep every night with phantom chain snatchers. Every bout left her charged with anger and often left her depressed. The episodes continued for several months until they finally stopped. How could a single stressful event have such extended consequences?

A new study by Indian scientists has gained insights into how a single instance of severe stress can lead to delayed and long-term psychological trauma. The work pinpoints key molecular and physiological processes that could be driving changes in brain architecture.

The team, led by Sumantra Chattarji from the National Centre for Biological Sciences (NCBS) and the Institute for Stem Cell Biology and Regenerative Medicine (inStem), Bangalore, have shown that a single stressful incident can lead to increased electrical activity in a brain region known as the amygdala. This activity sets in late, occurring ten days after a single stressful episode, and is dependent on a molecule known as the N-Methyl-D-Aspartate Receptor (NMDA-R), an ion channel protein on nerve cells known to be crucial for memory functions.

The amygdala is a small, almond-shaped groups of nerve cells that is located deep within the temporal lobe of the brain. This region of the brain is known to play key roles in emotional reactions, memory and making decisions. Changes in the amygdala are linked to the development of Post-Traumatic Stress Disorder (PTSD), a mental condition that develops in a delayed fashion after a harrowing experience.

Previously, Chattarji’s group had shown that a single instance of acute stress had no immediate effects on the amygdala of rats. But ten days later, these animals began to show increased anxiety, and delayed changes in the architecture of their brains, especially the amygdala. “We showed that our study system is applicable to PTSD. This delayed effect after a single episode of stress was reminiscent of what happens in PTSD patients,” says Chattarji. “We know that the amygdala is hyperactive in PTSD patients. But no one knows as of now, what is going on in there,” he adds.

Investigations revealed major changes in the microscopic structure of the nerve cells in the amygdala. Stress seems to have caused the formation of new nerve connections called synapses in this region of the brain. However, until now, the physiological effects of these new connections were unknown.

In their recent study, Chattarji’s team has established that the new nerve connections in the amygdala lead to heightened electrical activity in this region of the brain.

“Most studies on stress are done on a chronic stress paradigm with repeated stress, or with a single stress episode where changes are looked at immediately afterwards — like a day after the stress,” says Farhana Yasmin, one of the Chattarji’s students. “So, our work is unique in that we show a reaction to a single instance of stress, but at a delayed time point,” she adds.

Furthermore, a well-known protein involved in memory and learning, called NMDA-R has been recognised as one of the agents that bring about these changes. Blocking the NMDA-R during the stressful period not only stopped the formation of new synapses, it also blocked the increase in electrical activity at these synapses. “So we have for the first time, a molecular mechanism that shows what is required for the culmination of events ten days after a single stress,” says Chattarji. “In this study, we have blocked the NMDA Receptor during stress. But we would like to know if blocking the molecule after stress can also block the delayed effects of the stress. And if so, how long after the stress can we block the receptor to define a window for therapy,” he adds.

Chattarji’s group first began their investigations into how stress affects the amygdala and other regions of the brain around ten years ago. The work has required the team to employ an array of highly specialised and diverse procedures that range from observing behaviour to recording electrical signals from single brain cells and using an assortment of microscopy techniques. “To do this, we have needed to use a variety of techniques, for which we required collaborations with people who have expertise in such techniques,” says Chattarji. “And the glue for such collaborations especially in terms of training is vital. We are very grateful to the Wadhwani Foundation that supports our collaborative efforts and to the DBT and DAE for funding this work,” he adds.

{A lot of people chew gum for the mint, others for its sweetness, some to keep their mouth busy, and many other reasons.}

There are many reasons why people chew gum, but chewing gum is actually bad for your teeth and health.

These are some of its dangers.

{{1. It can cause headaches }}

Chewing gum for long spells can cause undue tightness in your muscles located close to your temples. This can put pressure on the nerves that supply this area of your head, and could cause intermittent headaches.

{{2. Gastrointestinal problems
}}

Chewing gum could cause you to swallow excessive air, which isn’t good for your stomach and can put pressure on your intestine. This could lead to cramps, bloating, abdominal pain and IBS (Irritable Bowel Syndrome).

{{3. It would make you crave for junk foods more }}

Research has found that chewing gum might make you lose your motivation to eat real food and crave for junk foods instead, which isn’t good for your health.

{{4. It could cause jaw disorder }}

Chewing gum makes you overuse your muscles, and when you overuse your muscles, there’ll definitely be repercussions. As per the jaws, it could create an imbalance in your jaw muscles, and even temporomandibular joint disorder in your jaw. Overusing the muscles in your jaw could also lead to headaches, toothaches and earaches.

{{5. It could damage your teeth }}

The sugar in chewing gum could damage your teeth. Most chewing gums contain preservatives, acidic flavouring and sugar — which could ruin your teeth and cause tooth decay.

{{6. It hinders metabolism }}

Metabolism is very important, but chewing gum alters the metabolic process. Chewing gum triggers the stimulation of saliva for an unnecessarily long time, and this could alter certain metabolic functions.

7. At the end of the day, chewing gum doesn’t really give you fresh breath; it only masks bad breath for a short period.

Are you addicted to chewing gum? You might be doing yourself m

{Can diet alo{ne be used to cure Crohn’s disease and ulcerative colitis (UC)? It’s a question Dr. David Suskind, a gastroenterologist at Seattle Children’s, has been researching for years.}
{{
Today, he finally has the answer: yes.}}

In a first-of-its-kind-study led by Suskind, published today in the Journal of Clinical Gastroenterology, diet alone was shown to bring pediatric patients with active Crohn’s and UC into clinical remission.

“This changes the paradigm for how we may choose to treat children with inflammatory bowel disease,” said Suskind.

In the small, prospective study, patients were put on a special diet called the specific carbohydrate diet (SCD) for 12 weeks as the sole intervention to treat their Crohn’s or UC. SCD is a nutritionally balanced diet that removes grains, dairy, processed foods and sugars, except for honey. The diet promotes only natural, nutrient-rich foods, which includes vegetables, fruits, meats and nuts.

At the end of the 12 weeks, eight out of the 10 patients who finished the study showed significant improvement and achieved remission from the dietary treatment alone.

{{Finding a cure for IBD}}

At most centers, treatment for inflammatory bowel disease (IBD) is limited and usually takes patients down one of two routes: steroids or medication, which can often lead to life-long side effects. Another concern is that medication and steroids only suppresses the immune system and don’t treat the underlying issue of the microbiome, the bacteria that lives in the digestive tract.

IBD refers to several related illnesses that affect the digestive tract. Crohn’s and UC are two forms of IBD. Doctors believe that IBD happens because something goes wrong between a child’s genetic makeup, their immune system and their microbiome. In most people, the bacteria in the digestive tract are harmless. Although in some cases, the microbiome goes awry and causes a person’s immune system to attack the bowel. It’s still unknown why this happens.

Suskind was determined to find better and more effective treatment options for IBD, and so he began spearheading research on the innovative diet known as SCD.

“For decades or longer, medicine has said diet doesn’t matter, that it doesn’t impact disease,” said Suskind. “Now we know that diet does have an impact, a strong impact. It works, and now there’s evidence.”

To date, there have only been a few case reports where a whole food diet, like SCD, has been used as a potential treatment for IBD. This study is the first to show, not just anecdotally, that the diet is safe and effective.

“Each person’s disease is unique, just as each person is unique,” said Suskind. “SCD is another tool in our tool belt to help treat these patients. It may not be the best treatment option for everyone, but it is an effective treatment for those who wish to try a dietary therapy.”

{{“There had to be a better way”}}

In October 2013, Nicole Kittelson noticed something wasn’t quite right with her then 8-year-old daughter Adelynne. Her skin and eyes had turned gray, her hair was brittle and she was losing weight.

“When we first took her to see her pediatrician, they simply said, ‘She’s a kid. She’s just active and needs more calories,’ but my gut was telling me something was wrong,” said Kittelson.

Shortly after, the family found themselves in the emergency room. Doctors tested Adelynne for leukemia and diabetes, but nothing came back with any answers as to what was going on inside Adelynne’s body. She was put on antibiotics and steroids and was sent home. For three weeks she was doing better, until one day things took a turn.

“She just started getting progressively worse,” said Kittelson.

{{Receiving an unexpected diagnosis}}

After multiple emergency room visits and months of uncertainty, Adelynne was admitted to Seattle Children’s where she met Suskind and was given a diagnosis: Crohn’s.

Common symptoms of Crohn’s include cramping, diarrhea and inflammation of the intestine. Crohn’s symptoms can range from mild pain to pain so severe a child may double over in pain. Additional complications can include dehydration, anemia and weight loss.

“Dr. Suskind walked us through the various treatment options,” said Kittelson. “He told us to think about which one we felt was best for our family. In the end, we wanted to try SCD. We knew it wouldn’t be easy, but in the long run, I didn’t want Adelynne to suffer the life-long side effects from medication or steroids. The diet was our best option. She was in so much pain from the Crohn’s, and I wanted to take that pain away.”

Seattle Children’s offers innovative therapies that are not offered at other centers across the country. Medicine isn’t always the answer for IBD. Diet, as Suskind has been advocating, plays a big role. At Seattle Children’s there are many alternative options including exclusive enteral nutrition (EEN) and SCD that can help children feel better and reduce inflammation without medication or steroids.

For 15 weeks the family started treatment using EEN, a diet that consisted of only formula. After 15 weeks on EEN, the family transitioned Adelynne to SCD with the help of her care team at Seattle Children’s.

“It was hard at first,” said Kittelson. “We got really good at reading labels and learning what foods were illegal, but after a while it became second nature.”
{{
A diet change, a life change}}

Today, Adelynne has been in clinical remission for more than two years. She’s a healthy, happy and thriving 11-year-old girl.

“I can’t believe how far we’ve come. When we first walked into Seattle Children’s, she was an 8-year-old girl who was barely heavier than our 4-year-old. Now, she’s growing and foods are no longer an enemy.”

Adelynne and her family have embraced shopping local for natural, nutrient rich foods. And although it’s been an adjustment, the family now says the diet is just part of their every day life.

“Her lunch doesn’t look much different than other kids at school,” said Kittelson. “There are so many options out there. We haven’t felt like we’ve had to sacrifice. We’ve even adjusted holiday traditions to fit into our new lifestyle. Instead of candy for special occasions, we swap them for other things.”

For Adelynne and her family, SCD was the right treatment option. It’s helped Adelynne get back to her normal life and find a love for food again.

“I don’t have the words to thank Dr. Suskind for what he did for us,” said Kittelson. “We are so in love with that man. He’s an extraordinary doctor who weighed our concerns and continues to walk us through everything. To have a doctor that is willing to explore other options and is willing to try new things, it’s incredible. There is no one right option for everyone. No one responds the same way. He listened to us and was our advocate when we needed one.”

{Welders exposed to airborne manganese at estimated levels below federal occupational safety standards exhibit neurological problems similar to Parkinson’s disease, according to new research at Washington University School of Medicine in St. Louis. Further, the more they are exposed to manganese-containing welding fumes, the faster the workers’ signs and symptoms worsen.}

The findings, published Dec. 28 in Neurology, suggest that current safety standards may not adequately protect welders from the dangers of the job.

“We found that chronic exposure to manganese-containing welding fumes is associated with progressive neurological symptoms such as slow movement and difficulty speaking,” said Brad A. Racette, MD, a professor of neurology and the study’s senior author. “The more exposure you have to welding fumes, the more quickly those symptoms progress over time.”

At high levels, manganese — a key component of important industrial processes such as welding and steelmaking — can cause manganism, a severe neurologic disorder with symptoms similar to Parkinson’s disease, including slowness, clumsiness, tremors, mood changes, and difficulty walking and speaking. The risk of manganism drove the Occupational Safety and Health Administration (OSHA) decades ago to set standards limiting the amount of manganese in the air at workplaces. While these safety standards are widely believed to have eliminated manganism as an occupational hazard, researchers who study the effects of manganese exposure have long suspected that there may still be some health effects at levels much lower than what is allowable per OSHA standards.

“Many researchers view what’s allowable as too high a level of manganese, but until now there really weren’t data to prove it,” said Racette, who also is executive vice chairman in the Department of Neurology. “This is the first study that shows clinically relevant health effects that are occurring at estimated exposures that are an order of magnitude lower than the OSHA limit.”

Racette and colleagues studied 886 welders at three worksites in the Midwest — two shipyards and one heavy-machinery fabrication shop. Each welder filled out a detailed job history questionnaire, which the researchers used to calculate each participant’s exposure by combining the estimated manganese exposure for specific job titles with the amount of time spent in each job.

Each participant also underwent at least two standardized clinical evaluations of motor function spaced a year or more apart and using the Unified Parkinson’s Disease Rating Scale. The evaluations were performed by trained neurologists looking for signs of neurological damage such as muscle stiffness, gait instability, reduced facial expressions and slow movement.

A score of 6 or lower was considered normal on the evaluation scale, and those with scores of 15 or higher were placed in the parkinsonism category. Parkinsonism is a set of neurological signs and symptoms similar to what is seen in Parkinson’s disease. At their first evaluation, the welders had an average score of 8.8, and 15 percent of the welders fell into the parkinsonism category.

Moreover, participants’ scores increased over time, and the welders exposed to the highest levels of manganese showed the biggest changes in their scores, an indication that their neurological problems were worsening faster than those of workers exposed to less manganese.

The scores for workers at the same sites who were not exposed to welding fumes did not change over time, suggesting that welding fumes, not aging, were responsible for the increasing scores.

Racette’s team did not directly measure the participants’ quality of life, but previous studies by his team have shown that higher parkinsonism scores in welders are associated with more difficulty with activities of daily life such as eating, mobility and writing.

“This is not something we can ignore,” Racette said. “I think a qualified neurologist would look at these clinical signs and say, ‘There’s something wrong here.’ This would be having an effect on people’s lives.”

The most worrisome aspect of the study, Racette said, is that the neurological signs showed up in people with an estimated exposure of only 0.14 milligrams of manganese per cubic meter of air, far below the safety standard set by OSHA at 5 milligrams per cubic meter.

In 2013, the American Conference of Governmental Industrial Hygienists recommended a limit of 0.02 milligrams of manganese per cubic meter. Some companies already are attempting to keep their workers’ exposures below that level by improving ventilation, mandating personal protective equipment and using low-manganese welding wire. However, only OSHA’s standards are enforceable by law.

“We can make the workplace safer for welders,” Racette said. “Reducing OSHA’s allowable levels of manganese would probably make a big difference in terms of safety and help workers avoid such risks.”

{Many women crave having a big butt, and to women like these, the major reason they want that big butt is to attract the opposite sex. However, science has found more reasonable reasons why having a big butt isn’t so bad after all.}

1. Researchers have found a link between bigger butts and healthier cholesterol levels. According to research, women with bigger butts and smaller waists tend to have higher levels of HDL cholesterol (the good kind of cholesterol that helps keep your arteries clear) and lower levels of LDL cholesterol (the bad kind of cholesterol that blocks arteries).

2. Evolutionary theorists have tried to find some connection between emotional intelligence and butt size. These theorists believe that shapely women who have the largest butts and smallest waists appeal to so many men, that they needed to develop superior social skills to assess and select potential mates.

3. Bigger and firmer butts can help protect your lower back. According to Pamela M. Peeke, M.D., a physician and spokesperson for the American College of Sports Medicine; when your butt is too weak to propel your legs forward as you walk, smaller muscles end up kicking in to help, and this can lead to strains in your back, hips and knees.

4. According to Dr Peeke, a strong butt can help lengthen your hip flexors and keep everything in alignment, giving you a good posture. Whereas, tight hips, an inevitable result of excessive sitting, can make it difficult for you to stand up straight.

5. According to a study published in Evolution and Human Behavior, men prefer women with fuller butts because it enhances the appearance of the curvature of the spine.

So, having bigger butts might not be bad after all.

{Making muscles burn more fat and less glucose can increase exercise endurance, but could simultaneously cause diabetes, says a team of scientists from Baylor College of Medicine and other institutions.}

Mouse muscles use glucose (carbohydrate) as fuel when the animals are awake and active and switch to fat (lipid) when they are asleep. The team discovered that disrupting this natural cycle may lead to diabetes but, surprisingly, also can enhance exercise endurance. The switch is controlled by a molecule called histone deacetylase 3, or HDAC3. This finding opens the possibility of selecting the right time to exercise for losing body fat but also raises the concern of using HDAC inhibitors as doping drugs for endurance exercise. The study appears in Nature Medicine.

“How the muscle uses glucose is regulated by its internal circadian clock that anticipates the level of its activity during the day and at night,” said senior author Dr. Zheng Sun, assistant professor of medicine — diabetes, endocrinology and metabolism, and of molecular and cellular biology at Baylor. “The circadian clock works by turning certain genes on and off as the 24-hour cycle progresses. HDAC3 is a key connection between the circadian clock and gene expression. Our previous work showed that HDAC3 helps the liver alternate between producing glucose and producing lipid. In this work, we studied how HDAC3 controls the use of different fuels in skeletal muscle.”

Skeletal muscles, the voluntary muscles, are important in the control of blood glucose in the body. They consume most of the glucose, and if they develop insulin resistance and consequently are not able to use glucose, then diabetes likely will develop. To study the role of HDAC3 in mouse skeletal muscle, Sun and colleagues genetically engineered laboratory mice to deplete HDAC3 only in the skeletal muscles. Then they compared these knocked out mice with normal mice regarding how their muscles burn fuel.

{{Unexpected results}}

When normal mice eat, their blood sugar increases and insulin is released, which stimulates muscles to take in and use glucose as fuel. “When the knocked out mice ate, their blood sugar increased and insulin was released just fine, but their muscles refused to take in and use glucose,” said Sun. “Lacking HDAC3 made the mice insulin resistant and more prone to develop diabetes.”

Yet, when the HDAC3-knocked out mice ran on a treadmill, they showed superior endurance, “which was intriguing because diabetes is usually associated with poor muscle performance,” said Sun. “Glucose is the main fuel of muscle, so if a condition limits the use of glucose, the expectation is low performance in endurance exercises. That’s the surprise.”

The researchers then studied what fueled the HDAC3-knocked out mice’s stellar performance using metabolomics approaches and found that their muscles break down more amino acids. This changed the muscles’ preference from glucose to lipids and allowed them to burn lipid very efficiently. This explains the high endurance, because the body carries a much larger energy reservoir in the form of lipid than carbohydrate.

The finding challenges the widely-used carbohydrate-loading (carbo-loading) strategy for improving endurance performance. “Carbo-loading didn’t make evolutionary sense before the invention of agriculture,” said Sun. “Switching muscles from using carbohydrates to lipids could increase exercise endurance, especially for low-intensity exercise.” The study suggests that HDAC inhibitors, a class of small molecule drugs currently being tested for treating several diseases, could potentially be used to manipulate such fuel switch in muscle and therefore raises concern of doping.

{{Link to the body’s internal clock}}

The team performed a number of functional genomics studies that established the link between HDAC3 and the circadian clock. “In normal mice, when the mouse is awake, the clock in the muscle anticipates a feeding cycle and uses HDAC3 to turn off many metabolic genes. This leads the muscles to use more carbohydrate,” said Sun. “When the animal is about to go to sleep and anticipates a fasting cycle, the clock removes HDAC3. This leads the muscles to use more lipid.”

Although these studies were done in mice, the researchers speculate that human muscles most likely will follow the same cycle. The study opens the possibility of promoting body fat burning by increasing exercise activity during the periods in which muscles use lipid, which is at night for people. “Losing body fat would be easier by exercising lightly and fasting at night,” said Sun. “It’s not a bad idea to take a walk after dinner.”