Intermittent fasting, and fasting in general, has been a popular fad health gimmick, but the science isn't on its side. Instead, proponents believe mice are little people so if mice weaned on starvation diets lived longer, people would also.
How fast tropical forests recover after deforestation has major consequences for climate change mitigation. A team including Smithsonian scientists discovered that some secondary tropical forests recover biomass quickly: half of the forests in the study attained 90 percent of old-growth forest levels in 66 years or less. Conservation planners can use their resulting biomass-recovery map for Latin America to prioritize conservation efforts.
Twenty thousand years ago, when humans were still nomadic hunters and gatherers, low concentrations of carbon dioxide in the atmosphere allowed the earth to fall into the grip of an ice age. But despite decades of research, the reasons why levels of the greenhouse gas were so low then have been difficult to piece together.
New research, published today in the leading journal Nature, shows that a big part of the answer lies at the bottom of the world. Sediment samples from the seafloor, more than 3 kilometers beneath the ocean surface near Antarctica, support a long-standing hypothesis that more carbon dioxide was dissolved in the deep Southern Ocean at times when levels in the atmosphere were low.
Boston, MA - A new study suggests that the current recommendation to treat severely malnourished children with routine antibiotics does not increase the likelihood of nutritional recovery in uncomplicated cases. Given this finding, the study's authors say that routinely using antibiotics may not be necessary or beneficial for severely malnourished children being treated at home when there is adequate local health infrastructure.
Reducing routine antibiotic use would be prudent given global concern over the problem of antibiotic resistance, say the researchers.
The study will appear in the February 4, 2016 issue of the New England Journal of Medicine (NEJM).
ROCHESTER, Minn. -- In a review article published in the Feb. 4 issue of the New England Journal of Medicine, a pair of Mayo Clinic Cancer Center researchers provide an in-depth look at the issues associated with the care of women in families with hereditary breast and ovarian cancer syndrome who have not yet developed cancer themselves. The article addresses optimal risk assessment for breast and ovarian cancers, the usefulness of risk-reducing surgery, side effects of these procedures, alternative strategies for cancer prevention and the best ways to help with the decision-making process.
PHILADELPHIA (February 3, 2016) - Cases of pertussis (whooping cough) have increased dramatically over the past five years, putting infants at risk of serious illness or death. Most infants are infected by a caregiver who has not received a Tdap (tetanus, diphtheria, and pertussis) booster, so caregiver immunization is particularly important. However, many caregivers go unvaccinated, and new strategies are needed to convince those living with infants to get the Tdap booster.
MAYWOOD, Il. - The widespread belief that radiation from X rays, CT scans and other medical imaging can cause cancer is based on an unproven, decades-old theoretical model, according to a study published in the American Journal of Clinical Oncology.
The model, known as linear no-threshold (LNT), is used to estimate cancer risks from low-dose radiation such as medical imaging. But risk estimates based on this model "are only theoretical and, as yet, have never been conclusively demonstrated by empirical evidence," corresponding author James Welsh, MD and colleagues write. Use of the LNT model drives unfounded fears and "excessive expenditures on putative but unneeded and wasteful safety measures."
Prolonged hammering and chiselling accelerated degenerative arthritis in the hands of Michelangelo Buonarroti, sculptor, painter and one of the greatest artists of all time. But the intense work probably helped him keep the use of his hands right up until he died.
February 3, 2016 - How has new legislation affected marijuana use in the United States? The best available data suggest that marijuana use is increasing in adults but not teens, with a decrease in marijuana-related arrests but an increase in treatment admissions, according to an update in the January/February Journal of Addiction Medicine, the official journal of the American Society of Addiction Medicine (ASAM). The journal is published by Wolters Kluwer.
Researchers have for the first time witnessed the death of a female orangutan at the hands of another female. Even more extraordinary is that the perpetrator recruited a male orangutan as a hired gun to help her corner and attack the victim. Before this observation, lethal fights between females had never been observed in orangutans; in other primates such fights occur mainly between males, according to Anna Marzec of the University of Zurich in Switzerland. She is the lead author of a report on the fatal incident, which appears in Springer's journal Behavioral Ecology and Sociobiology.
Depression is a serious issue for expecting mothers. Left untreated, depression could have implications for a fetus's health. But treating the disease during pregnancy may carry health risks for the developing fetus, which makes an expecting mother's decision whether to take medication a very difficult one. To better understand how antidepressants affect fetuses during pregnancy, scientists studied exposure in mice. They report their findings in the journal ACS Chemical Neuroscience.
The undefined blanket term "dark matter", what must exist in the universe to account for missing mass, is invoked for just about everything, and so a lot of claims are made affirming they have evidence for it. But one claim, that bursts of gamma rays are such, is instead other astrophysical phenomena such as fast-rotating stars called millisecond pulsars, according to two new studies in Physical Review Letters.
Previous papers suggested that gamma rays coming from the dense region of space in the inner Milky Way galaxy could be caused when invisible dark matter particles collide. But using new statistical analysis methods, two research teams independently found that the gamma ray signals are uncharacteristic of those expected from dark matter.
Researchers have shown that an enzyme key to regulating gene expression -- and also an oncogene when mutated -- is critical for the expression of numerous inflammatory compounds that have been implicated in age-related increases in cancer and tissue degeneration,
Inhibitors of the enzyme are being developed as a new anti-cancer target.
Aged and damaged cells frequently undergo a form of proliferation arrest called cellular senescence. These fading cells increase in human tissues with aging and are thought to contribute to age-related increases in both cancer and inflammation. The secretion of such inflammatory compounds as cytokines, growth factors, and proteases is called the senescence-associated secretory phenotype, or SASP.
