Women using depot medroxyprogesterone acetate (DMPA), commonly known as Depo-Provera or the birth control shot, have a moderately increased risk of becoming infected with HIV, a large meta-analysis of 12 studies involving more than 39,500 women published in The Lancet Infectious Diseases has found. Other forms of hormonal contraception, including oral contraceptive pills, do not appear to increase this risk.
Body
Those who overindulged during the holidays may want to get a shot of cold air to kick-start some extra fat-burning activity for the new year.
Since it is only January 8th, most people have not yet given up on their New Year's Resolution to get in shape so this is still relevant.
Despite what supplement salespeople - and an alarming number of nutritionists in 2015 who make money promoting them - the only ways to lose weight are to starve or work up a sweat. And working up a sweat is the smart way to go.
Before you pack your gym bag, pack your brain with some crazy facts about sweat, courtesy of American Chemical Society's Sophia Cai in the Speaking of Chemistry series.
Brownbanded bamboo sharks take the term "resourceful" to a whole new level. Biologists have found that a shark egg case dropped by an adult bamboo shark showed signs of healthy development. What surprised them was that the aquarium's female Chiloscyllium punctatum adults had spent nearly four years--45 months--in complete isolation from males.
Eating one avocado a day as part of a heart healthy, cholesterol-lowering moderate-fat diet can help improve bad cholesterol levels in overweight and obese individuals, according to new research. Researchers evaluated the effect avocados had on traditional and novel cardiovascular risk factors by replacing saturated fatty acids from an average American diet with unsaturated fatty acids from avocados.
Bacteria that have evolved to help us digest the yeast that give beer and bread their bubbles could support the development of new treatments to help people fight off yeast infections and autoimmune diseases such as Crohn's disease, researchers report.
The study shows how microbes in our digestive tract have learned to unravel the difficult to break down complex carbohydrates that make up the yeast cell wall. It's published by scientists from Newcastle University in the United Kingdom and the University of Michigan Medical School.
Since the discovery of how DNA encodes genetic information, most research on the evolution of life has focused on genes. According to the "selfish gene" theory, cells and organisms exist simply as packages to protect and transmit genes. New research challenges this idea, proposing instead that if anything is "selfish" it must be the ribosome. That up-ends everything we think we know about the evolution of life and, in fact, the function of ribosomes themselves.
A small protein active in the human immune response can disable bacterial toxins by exploiting a property that makes the toxins effective - but also turns out to be a weakness.
These toxins, which are released by bacteria, have malleable surfaces that allow them to move through porous areas of host cells to pave the way for bacteria to stay alive. But that same malleability makes the toxins vulnerable to these immune system proteins, which bind to the toxins and render them useless.
Most snakebite deaths, and most hospital admissions, are due to brown snakes. Credit: Flagstaffotos (http://www.flagstaffotos.com.au/), CC BY-NC (http://creativecommons.org/licenses/by-nc/4.0/)
A study of circadian rhythms in skin stem cells found that this clock plays a key role in coordinating daily metabolic cycles and cell division.
The in Cell Reports shows for the first time how the body's intrinsic day-night cycles protect and nurture stem cell differentiation. Furthermore, this work offers novel insights into a mechanism whereby an out of synch circadian clock can contribute to accelerated skin aging and cancers.
It is estimated that a third of women in the United States will have had a hysterectomy by the age of 60. That sounds like a lot but it has actually gone down and a new study of more than three thousand women in Michigan who underwent hysterectomy for benign indications reveals that alternatives to hysterectomy are being underused and that treatment guidelines are often not followed.
Researchers have discovered that a drug FDA-approved to treat overactive bladder may boost brown fat's metabolic powers, making it a promising candidate for combating obesity. Unlike energy-storing white fat, brown fat burns energy to generate heat, which can help maintain body weight and prevent obesity in rodents.
Can spiders be carriers of human pathogens? Can they cause an infection through a break in the skin?
A team of scientists has data-mined the history of publications on spider envenomations to conclude that the evidence for spider-vectored infection is scanty. Further, the researchers note that the mere presence of bacteria on spider fangs or mouthparts does not establish spiders as vectors for these bacteria.
Staying active allows you to age optimally, according to a small study in The Journal of Physiology. The analysis of amateur older cyclists found that many had levels of physiological function that would place them at a much younger age compared to the general population; debunking the common assumption that aging automatically makes you more frail.
The researchers recruited 84 male and 41 female cycling enthusiasts aged 55 to 79 to explore how the aging process affects the human body, and whether specific physiological markers can be used to determine your age.
Adding radiation treatment to hormone therapy saves more lives among older men with locally advanced prostate therapy than hormone therapy alone, according to a new study in the Journal of Clinical Oncology this week from Penn Medicine researchers.