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Did dinosaurs have lice? Researchers say it's possible

CHAMPAIGN, Ill. — A new study louses up a popular theory of animal evolution and opens up the possibility that dinosaurs were early – perhaps even the first – animal hosts of lice.

The study, in Biology Letters, uses fossils and molecular data to track the evolution of lice and their hosts. It offers strong evidence, the researchers said, that the ancestors of lice that today feed on birds and mammals began to diversify before a mass extinction event killed off the dinosaurs about 65 million years ago.

Climate change is making our environment 'bluer'

The "colour" of our environment is becoming "bluer", a change that could have important implications for animals' risk of becoming extinct, ecologists have found. In a major study involving thousands of data points and published this week in the British Ecological Society's Journal of Animal Ecology, researchers examined how quickly or slowly animal populations and their environment change over time, something ecologists describe using "spectral colour".

Face time with a female aids males bent on monkey business

New Haven, Conn. – Male monkeys looking for a good time might benefit from spending a bit longer getting to know a potential mate, according to a new study published online in the scientific journal Proceedings of the Royal Society B.

The time males spend around a prospective mate might be the key to detecting subtle sexual signals that show which females are fertile and which are not, according to the study, co-authored by an international team of biologists and psychologists.

Obesity increases the risk of fetal and infant death, and the risk of complications after hysterectomy

Women who are obese during early pregnancy have a significantly increased risk of their baby dying before, during or up to one year after birth, according to research published in Europe's leading reproductive medicine journal Human Reproduction today [1]. A second paper [2] also published in the journal today shows that obesity increases the risk of complications, such as bleeding and infections, during and after a hysterectomy operation.

Overseas doctors more likely to face serious GMC action

General Medical Council (GMC) decisions about doctors who qualified outside the UK are more likely to have far reaching consequences (high impact decisions), finds research published on bmj.com today.

The authors, led by Professor Charlotte Humphrey from King's College London, say there is no clear reason why overseas doctors do worse in GMC fitness to practise processes than their UK-trained peers.

Rejuvenating electron microscopy

Modifying a protein from a plant much favored by science, researchers at the University of California, San Diego School of Medicine and colleagues have created a new type of genetic tag visible under an electron microscope, illuminating life in never-before-seen detail.

Off-label marketing of medicines in the US is rife but difficult to control

Despite Federal Drug Administration regulation of the approval and use of pharmaceutical products, "off-label" marketing of drugs (for purposes other than those for which the drug was approved) has occurred in all aspects of the US health care system. In a study published in this week's PLoS Medicine, Aaron S. Kesselheim from Brigham and Women's Hospital, Boston, USA and colleagues report that the most common alleged off-label marketing practices also appear to be the most difficult to control through external regulatory approaches.

Reef diversity no insurance against human threats

In a large collaborative analysis publishing tomorrow in the online, open access journal PLoS Biology, 55 scientists from 49 nations document that the capability of reef fish systems to produce biomass and deliver goods and services to humanity, is functionally linked to the number of species; functioning increases as biodiversity increases. However, mounting pressures from growing human populations is tampering with this functioning of the reef fish communities, especially in the most diverse reefs.

Rejuvenating electron microscopy

By modifying a protein from a plant that is much favored by science, researchers at the University of California, San Diego School of Medicine and colleagues have created a new type of genetic tag visible under an electron microscope, illuminating life in never-before-seen detail. Led by Nobel laureate Roger Tsien, PhD, Howard Hughes Medical Institute investigator and UCSD professor of pharmacology, chemistry and biochemistry, a team of scientists radically re-engineered a light-absorbing protein from the flowering cress plant Arabidopsis thaliana.

World's reef fishes tussling with human overpopulation

In an unprecedented collaborative analysis published in the journal PLoS Biology, scientists from 49 nations demonstrated that the ability of reef fish systems to produce goods and services to humanity increases rapidly with the number of species. However, growing human populations hamper the ability of reefs to function normally, and counterintuitively, the most diverse reef fish systems suffer the greatest impairments from stressors triggered by human populations.

NIH, USU study maps hotspots of genetic rearrangement

Researchers have zoomed in on mouse chromosomes to map hotspots of genetic recombination — sites where DNA breaks and reforms to shuffle genes. The findings of the scientists at the National Institutes of Health and Uniformed Services University of Health Sciences (USU) have the potential to improve the detection of genes linked to disease and to help understand the root causes of genetic abnormalities. The research, published online April 3 in Nature, moves scientists one step closer to understanding how mammals evolve and respond to their environments.

Longer-term follow-up of users of estrogen therapy finds some changes in risks

Among postmenopausal women with prior hysterectomy who had used estrogen therapy for about 6 years and then stopped, longer-term follow-up indicates that the increased risk of stroke seen during the intervention period had dissipated, the decreased risk of hip fracture was not maintained, while the decreased risk of breast cancer persisted, according to a study in the April 6 issue of JAMA.

HIV-1 drug resistance mutations associated with increased risk of antiretroviral treatment failure

An analysis of data from 10 studies indicates that the presence of low frequency (also called "minority") human immunodeficiency virus type 1 (HIV-1) drug resistance mutations, particularly those involving nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance, are significantly associated with an increased risk of first-line antiretroviral treatment failure, according to an article in the April 6 issue of JAMA.

Death rates after hospitalization down for oldest heart failure patients

Death rates after hospitalization for heart failure have dropped for veterans age 80 and older, but rehospitalizations remain frequent, according to a study in the American Heart Association journal Circulation: Heart Failure.

Results of the study highlight a need to better identify which patients among the oldest are more likely to be rehospitalized not just for heart failure, but for any reason, said Rashmee Shah, M.D., lead author of the study and postdoctoral fellow in the Department of Health Research and Policy at Stanford University School of Medicine in Palo Alto, Calif.

Caution for estrogen therapy after hysterectomy

An editorial in the April 6 issue of the Journal of the American Medical Association cautions against estrogen-only hormone therapy in women who have had a hysterectomy because of longstanding evidence that it raises the risk of breast cancer.