More evidence for possible link between cocaine use and HIV infection

 

New UCLA research offers further evidence that cocaine use disrupts the immune system, making people who use it more likely to become infected with HIV. In research published online June 18 in the peer-reviewed journal Scientific Reports, researchers with the UCLA AIDS Institute and Center for AIDS Research used an advanced form of humanized mice -- that is, immunodeficient mice engineered to have a human-like immune system -- to study the effects of cocaine. The findings suggest that using cocaine makes people significantly more susceptible to HIV infection. 'Substance use and abuse is a major issue, especially when it comes to HIV infection,' said Dimitrios Vatakis, the study's senior author and an assistant professor of medicine in the division of hematology/oncology at the David Geffen School of Medicine at UCLA. 'There has been a general attitude, especially in the scientific but also the general community, that risky behavior is the main reason for higher infections. This study shows that under the same transmission conditions, drug exposure enhances infection through a collective of biological changes.' This study builds on previous research by Vatakis and others on his team showing that a three-day exposure to cocaine appears to make a unique population of immune cells called quiescent CD4 T cells, which are resistant to HIV, more susceptible to infection by stimulating two receptors in the cells, called σ1 and D4. Those findings suggested that cocaine use increases the pool of CD4 T cells in the human body that can become infected by the virus. As a result, the odds for productive infection and a larger viral reservoir increase. That study, however, was based on in-vitro research -- that is, research done in a petri dish -- which could have skewed the results. The next step was to find the same effect in in-vivo studies -- that is, those conducted with living organisms, such as mice. This is what the current paper has done. For this study, Vatakis and his team used the most advanced humanized mouse model, called BLT. The name comes from the way the model is generated: mice are transplanted with human hematopoietic stem cells (B, for blood cells) and donor-matched liver (L) and thymus (T) tissues, resulting in the development of a functioning human immune system. 'This study is the first of its kind using this model,' said Vatakis, who also directs the UCLA/CFAR Virology Core Laboratory. 'The BLT has been used to study HIV latency, cancer immunotherapy and now drug abuse and HIV infection. It very closely resembles the human immune system and it is the most relevant.' The researchers separated the mice into two major groups. Half of the mice were injected with cocaine every day for five days, while the other half were injected with saline for comparison. After five days, half the mice in each group were injected with HIV-1. Then all of the mice were given saline or cocaine for two more weeks. The researchers then collected blood and tissue samples to measure infection levels and examine other effects of the cocaine. They found that the cocaine/HIV group had higher amounts of HIV than the saline/HIV mice. They also found that nine of the 19 saline/HIV mice had undetectable amounts of the virus, compared with only three of the 19 cocaine/HIV mice. The researchers were surprised to find that despite the cocaine-induced inflammation prior to infection, the CD4 T cells that HIV targets were not overtly activated. Also, CD8 T cells, which kill infected cells, were not functional, even though they appeared to be so. 'This points to cocaine blunting the potency of our body's defense against the virus,' Vatakis said. While these studies have shed further light on the effects of cocaine use and misuse on HIV infection, this small animal model, although it closely mimics human immunity, does not fully re-create real-life settings. In addition, the study used an acute -- or brief, uninterrupted -- cocaine exposure regimen, rather than a more clinically relevant chronic use model, which could affect the results. The next stages of research, using the same BLT model, will be to determine how cocaine abuse might affect HIV transmission in mucosal membranes such as vaginal and anal tissues; how pre- and post-exposure prophylaxis (that is, taking medication to reduce the risk of acquiring HIV) can be affected by cocaine exposure; how cocaine might affect viral latency, the process in which a virus lies dormant in a cell; and how cocaine alters the body's immune defenses and affects other viral infections. Story Source: The above post is reprinted from materials provided by University of California - Los Angeles Health Sciences. Note: Materials may be edited for content and length. Journal Reference: Sohn G. Kim, Emily L. Lowe, Dhaval Dixit, Cindy Seyeon Youn, Irene J. Kim, James B. Jung, Robert Rovner, Jerome A. Zack, Dimitrios N. Vatakis. Cocaine-mediated impact on HIV infection in humanized BLT mice. Scientific Reports, 2015; 5: 10010 DOI: 10.1038/srep10010

Chemists devise technology that could transform solar energy storage

 

Fri, 06/19/2015 - 8:19am Melody Pupols, Univ. of California, Los Angeles   The scientists devised a new arrangement of solar cell ingredients, with bundles of polymer donors (green rods) and neatly organized fullerene acceptors (purple, tan). Image: UCLA ChemistryThe materials in most of today’s residential rooftop solar panels can store energy from the sun for only a few microseconds at a time. A new technology developed by chemists at the Univ. of California, Los Angeles (UCLA) is capable of storing solar energy for up to several weeks—an advance that could change the way scientists think about designing solar cells. The findings are published in Science. The new design is inspired by the way that plants generate energy through photosynthesis. “Biology does a very good job of creating energy from sunlight,” said Sarah Tolbert, a UCLA professor of chemistry and one of the senior authors of the research. “Plants do this through photosynthesis with extremely high efficiency.” “In photosynthesis, plants that are exposed to sunlight use carefully organized nanoscale structures within their cells to rapidly separate charges—pulling electrons away from the positively charged molecule that is left behind, and keeping positive and negative charges separated,” Tolbert said. “That separation is the key to making the process so efficient.” To capture energy from sunlight, conventional rooftop solar cells use silicon, a fairly expensive material. There is currently a big push to make lower-cost solar cells using plastics, rather than silicon, but today’s plastic solar cells are relatively inefficient, in large part because the separated positive and negative electric charges often recombine before they can become electrical energy. “Modern plastic solar cells don’t have well-defined structures like plants do because we never knew how to make them before,” Tolbert said. “But this new system pulls charges apart and keeps them separated for days, or even weeks. Once you make the right structure, you can vastly improve the retention of energy.” The two components that make the UCLA-developed system work are a polymer donor and a nanoscale fullerene acceptor. The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy. The plastic materials, called organic photovoltaics, are typically organized like a plate of cooked pasta—a disorganized mass of long, skinny polymer “spaghetti” with random fullerene “meatballs.” But this arrangement makes it difficult to get current out of the cell because the electrons sometimes hop back to the polymer spaghetti and are lost. The UCLA technology arranges the elements more neatly—like small bundles of uncooked spaghetti with precisely placed meatballs. Some fullerene meatballs are designed to sit inside the spaghetti bundles, but others are forced to stay on the outside. The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene, which can effectively keep the electrons away from the polymer for weeks. “When the charges never come back together, the system works far better,” said Benjamin Schwartz, a UCLA professor of chemistry and another senior co-author. “This is the first time this has been shown using modern synthetic organic photovoltaic materials.” In the new system, the materials self-assemble just by being placed in close proximity. “We worked really hard to design something so we don’t have to work very hard,” Tolbert said. The new design is also more environmentally friendly than current technology, because the materials can assemble in water instead of more toxic organic solutions that are widely used today. “Once you make the materials, you can dump them into water and they assemble into the appropriate structure because of the way the materials are designed,” Schwartz said. “So there’s no additional work.” The researchers are already working on how to incorporate the technology into actual solar cells. Yves Rubin, a UCLA professor of chemistry and another senior co-author of the study, led the team that created the uniquely designed molecules. “We don’t have these materials in a real device yet; this is all in solution,” he said. “When we can put them together and make a closed circuit, then we will really be somewhere.” For now, though, the UCLA research has proven that inexpensive photovoltaic materials can be organized in a way that greatly improves their ability to retain energy from sunlight. Source: Univ. of California, Los Angeles

Vitamin D

 

The truth about Vit D

Mysteries of the Brain: Emotional Brain

 

For years, researchers have struggled to understand how emotions are formed and processed by the brain. Now, neuroscientist Kevin LaBar and his graduate students at Duke University are using a virtual reality room to study how the brain reacts to both negative and positive emotions. "Mysteries of the Brain" is produced by NBC Learn in partnership with the NSF. Credit: NBC Learn and the National Science Foundation

Jimmy Choo Skatepark for His New Men Collection

 

Posted: 18 Jun 2015 10:29 AM PDT Les créatifs du Bureau Betak ont imaginé le « Jimmy Choo Sporting Club » au Seymour Leisure Center, à Londres : un skatepark géant pour le lancement de la nouvelle collection Hommes Spring/Summer 2016 de Jimmy Choo. Les athlètes-modèles ont fait un show de BMX et skateboarding, tous habillés par le créateur. Une identité visuelle a également été travaillée pour les vestiaires et boissons à disposition.

3D-printed objects created entirely from wood cellulose

 

The same material that gives trees their structural integrity can now be used to 3D print tiny chairs, electrical circuits, and other objects (Credit: Peter Widing) Image Gallery (4 images) The 3D printing revolution brings with it a harmful side effect: the special inks that it uses are derived (for the most part) from environmentally-unfriendly processes involving fossil fuels and toxic byproducts. But now scientists at Chalmers University of Technology have succeeded in using cellulose – the most abundant organic compound on the planet – in a 3D printer. They were also able to create electrically-conductive materials by adding carbon nanotubes. To be specific, the researchers used nanocellulose obtained from wood pulp. This is the stuff that forms the scaffolding that makes trees able to stand tall. It's available in massive quantities, plus it's biodegradable, incredibly strong, renewable, and reusing it keeps the carbon dioxide it contains from entering the atmosphere. Normally, 3D printing uses a heated liquid form of plastic or metal that hardens and solidifies as it cools and dries. But cellulose doesn't melt when you heat it, so it's not previously been considered a suitable material. The researchers mixed the cellulose in a hydrogel of 95-99 percent water, which allowed it to go into a 3D bioprinter, and in some instances with carbon nanotubes so that it could conduct electricity. The very high water content of the resultant printer gel meant that the drying process had to be carefully controlled so as not to lose the object's 3D structure. The scientists found that they could also allow the structure to collapse into a thin film (like a circuit). "Potential applications range from sensors integrated with packaging, to textiles that convert body heat to electricity, and wound dressings that can communicate with healthcare workers," says lead researcher Paul Gatenholm. "Our research group now moves on with the next challenge: to use all wood biopolymers besides cellulose." The researchers presented their findings at the New Materials From Trees conference in Stockholm earlier this week. Source: Chalmers University of Technology

15 years after smokers quit, heart failure risk may fall to normal

 

For most former smokers who quit at least 15 years ago, the risks of heart failure and death are the same as those of someone who never smoked, according to a new U.S. study.  “These results support the majority of literature, including that of the U.S. Surgeon General,” said senior author Dr. Ali Ahmed of the Center for Health and Aging at the Washington DC VA Medical Center. But those who were heavy smokers – meaning at least a pack a day for 32 years or more - do still have an elevated risk, even after 15 years, which was a surprise, Ahmed told Reuters Health by email. “While all individuals who quit smoking will benefit from a decreased chance of death, to achieve the full complement of health benefits of smoking cessation of one who has never smoked, smokers need to smoke less and quit early, and for those are not smokers – never start smoking,” he said. Ahmed and his coauthors used the ongoing Cardiovascular Health Study of adults over age 65, which included 2556 people who had never smoked, 629 current smokers and 1297 former smokers who had quit at least 15 years earlier. Of those who had quit, 312 had been heavy smokers, with 32 “pack-years” or more of smoking. After 13 years of follow-up, about 21 percent of never smokers and 21 percent of former smokers experienced heart failure. But among former smokers with at least 32 pack-years, almost 30 percent suffered heart failure. When the researchers accounted for other factors like age, sex, race, education, other health conditions and medications, current smokers were about 50 percent more likely to have heart failure than never smokers or former smokers, as reported in Circulation: Heart Failure. Over the same time period, current smokers were twice as likely to die from any cause, compared to never-smokers, and former heavy smokers were about 26 percent more likely than never-smokers to die. “When one smokes, it induces atherosclerosis, or the buildup of plaque in the arteries,” which narrows the arteries and increases the risk of blood clot or heart attack, Ahmed said. “However, when one quits smoking, the buildup of plaque and risk of blood of clots decreases, allowing one’s cardiovascular risk to return to normal over time.” “To date, this is the first study that investigated the role of amount and duration of prior smoking on the health benefits of prolonged cessation for former smokers,” said Dr. Gerasimos Siasos of Brigham and Women's Hospital in Boston, Massachusetts, who was not part of the study. Former heavy smokers may not achieve the health profile of never smokers, but the cardiovascular risk for them is definitely lower compared to current smokers, Siasos told Reuters Health by email. Quitting smoking also reduces the risk of lung cancer and other cancers of the upper gastrointestinal tract, said Bich Tran, a public health and epidemiology researcher at the University of New South Wales in Sydney, Australia. Tran was also not involved in the new study. Disease risk starts to decrease as soon as you quit, even for people of older age, she said. “Our body can heal itself,” Tran told Reuters Health by email. “Within 12 hours or few days after the smoking, the level of carbon monoxide in blood will decline and the circulatory system will start repairing the damage.” This is a slow process and sometimes quitting smoking can cause discomforts like weight gain, sore gums and tongue, coughing or trouble sleeping, she noted. “These results highlight the importance of smoking cessation for cardiovascular health and moreover support the notion that smokers who cannot quit should be encouraged to reduce their amount of smoking,” Siasos said. Doctors should target former heavy smokers for cardiovascular screening, he said. http://www.foxnews.com

Get the most out of home blood pressure monitoring

 

Checking your blood pressure at home is an important part of managing high blood pressure. Find out how to use home monitors accurately. By Mayo Clinic Staff Checking your blood pressure at home is an important part of managing high blood pressure The American Heart Association (AHA) and other organizations recommend that anyone with high blood pressure monitor his or her blood pressure at home. Home monitoring can help you keep tabs on your blood pressure in a familiar setting, make certain your medication is working, and alert you and your doctor to potential health complications. Blood pressure monitors are available widely and without a prescription, so home monitoring is an easy step toward improving your condition. Before you start, it's important to know the right technique and to find a good home blood pressure monitor. Why do I need to monitor my blood pressure at home? Monitoring your blood pressure at home can: Help with early diagnosis. Self-monitoring can help your doctor diagnose high blood pressure earlier than if you have only occasional blood pressure readings in a medical office. Home monitoring is especially important if you have slightly elevated blood pressure (prehypertension) or another condition that could contribute to high blood pressure, such as diabetes or kidney problems. Help track your treatment. The only way to know whether your lifestyle changes or medications are working is to check your blood pressure regularly. Monitoring blood pressure changes at home can help you and your doctor make decisions about your treatment, such as adjusting dosages or changing medications. Encourage better control. Self-monitoring can give you a stronger sense of responsibility for your health. You may feel even more motivated to control your blood pressure with an improved diet, physical activity and proper medication use. Cut your health care costs. Self-monitoring might decrease your number of visits to your doctor or clinic. Check if your blood pressure differs outside the doctor's office. Some people experience spikes in blood pressure due to anxiety associated with seeing a doctor (white coat hypertension). Other people have normal blood pressure at a clinic but elevated pressure elsewhere (masked hypertension). Monitoring blood pressure at home can help determine if you have true high blood pressure. Not everyone can track blood pressure at home. If you have an irregular heartbeat, home blood pressure monitors might not give you an accurate reading. Types of home monitors Most pharmacies, medical supply stores and some websites sell home blood pressure monitors. An automatic or electronic device is recommended. Discuss the choices with your doctor so that you pick the monitor that's best for your situation. Monitors generally have the same basic parts: Inflatable cuff. The cuff's inner layer fills with air and squeezes your arm. The cuff's outer layer has a fastener to hold the cuff in place. Heart rate and blood flow are automatically calculated by measuring the changes in the motion of your artery as the blood flows through while the cuff deflates. Gauge for readouts. Some blood pressure monitors can take multiple readings and report the averages. Digital monitors that are fitted on the upper arm are generally the most accurate. If you can't find a cuff big enough for your upper arm, ask your doctor about fitting a cuff to your lower arm or wrist. These types of cuffs can be difficult to use correctly. Ask your doctor if they might be options for you and how they should be used. Devices that measure your blood pressure at your finger aren't recommended.

The pain of my rheumatoid arthritis keeps me up at night. How can I reduce pain at night, so I can get some sleep?

 

Creating a comfortable sleep environment, caring for your joints before bedtime and exercising during the day can all help reduce pain and improve your sleep. Create an ideal sleep environment. Make sure your bed, pillows and blanket are comfortable. Keep your bedroom cool, dark and quiet. Stick to a routine. Try to go to bed and wake up at the same time each day. Avoid things that can disturb your sleep. It's best to do without alcohol, caffeine, large meals and TV close to bedtime. Research has shown that the bright light of a TV can interfere with sleep. Take time to unwind. Take a warm bath or shower before bedtime to help soothe your joints and muscles. Support your limbs. Propping your arms and legs with pillows might help reduce pain throughout the night. Be physically active during the day. Exercise can help improve sleep. However, don't exercise within three hours of going to bed. If your rheumatoid arthritis symptoms prevent you from getting enough sleep, you may feel fatigued the next day. Manage your fatigue by putting off unnecessary tasks, avoiding heavy meals, and taking rest breaks or naps throughout the day. source : www.mayoclinic.org

Men's health: Prevent the top threats

 

Many of the leading causes of death among men can be prevented. Here's what you need to know to live a longer, healthier life. By Mayo Clinic Staff Do you know the greatest threats to men's health? The list is surprisingly short. The top causes of death among adult men in the U.S. are heart disease, stroke, cancer and chronic lower respiratory disease, according to the Centers for Disease Control and Prevention. The good news is that a few lifestyle changes can significantly lower your risk of these common killers. Start by looking at your lifestyle: Take charge of your health by making healthier lifestyle choices. For example:  Don't smoke. If you smoke or use other tobacco products, ask your doctor to help you quit. It's also important to avoid exposure to secondhand smoke, air pollution and exposure to chemicals (such as in the workplace).  Eat a healthy diet. Choose vegetables, fruits, whole grains, high-fiber foods and lean sources of protein, such as fish. Limit foods high in saturated fat and sodium. Maintain a healthy weight. Losing excess pounds — and keeping them off — can lower your risk of heart disease as well as various types of cancer.  Get moving. Include physical activity in your daily routine. You know exercise can help you control your weight and lower your risk of heart disease and stroke. But did you know that it may also lower your risk of certain types of cancer? Choose sports or other activities you enjoy, from basketball to brisk walking.  Limit alcohol. If you choose to drink alcohol, do so only in moderation. For men, that means up to two drinks a day for men age 65 and younger and one drink a day for men older than age 65. The risk of various types of cancer, such as liver cancer, appears to increase with the amount of alcohol you drink and the length of time you've been drinking regularly. Too much alcohol can also raise your blood pressure.   Manage stress. If you feel constantly on edge or under assault, your lifestyle habits may suffer — and so might your immune system. Take steps to reduce stress — or learn to deal with stress in healthy ways.   Stop avoiding the doctor Don't wait to visit the doctor until something is seriously wrong. Your doctor can be your best ally for preventing health problems. Be sure to follow your doctor's treatment recommendations if you have health issues, such as high cholesterol, high blood pressure or diabetes. Also, be sure to ask your doctor about when you should have cancer screenings and other health evaluations. What else puts you at risk? Another common cause of death among men are motor vehicle accidents. To stay safe on the road, use common sense. Wear your seat belt. Follow the speed limit. Don't drive under the influence of alcohol or any other substances, and don't drive while sleepy. Suicide is another leading men's health risk. An important risk factor for suicide among men is depression. If you have signs and symptoms of depression — such as feelings of sadness or unhappiness and loss of interest in normal activities — consult your doctor. Treatment is available. If you're contemplating suicide, call for emergency medical help or go the nearest emergency room. The bottom line Understanding health risks is one thing. Taking action to reduce your risks is another. Start with healthy lifestyle choices — eating a healthy diet, staying physically active, quitting smoking and getting recommended health screenings. The impact may be greater than you'll ever know.