Frontiers : The month in research

Cardiology
Heart failure runs in families
N Engl J Med 2006;368:210-5

We already know that some cardiovascular diseases run in families. US researchers have found that having at least one parent with heart failure increased the risk in offspring by 70% during a mean follow-up of 20 years. They used data from the Framingham heart study, which began 50 years ago, and data from the study of the original cohort's children, which began in 1971. In a linked cross sectional analysis, these children were also about twice as likely to have asymptomatic left ventricular systolic dysfunction compared with children whose parents did not have heart failure.

Both analyses were adjusted for multiple risk factors-age, sex, prior heart attack, diabetes, blood pressure, height, and weight-which suggests that the effect of family history is inde- pendent and worth asking about when taking routine history.

Regenerative medicine
From stem cells to T lymphocytes
Proc Natl Acad Sci U S A 2006;103:11 742-7

Under appropriate cues, geneti- cally manipulated human embryonic stem cells can differ- entiate into required lineages. So much is agreed, but how exactly this differentiation occurs is open to question. Researchers can now culture embryonic stem cells in vitro on the stromal cells of mouse bone marrow and then engraft these stem cells within human thymic tissue into immunodeficient mice. This could, in theory, help patients with T cell disorders, which are usually severe and lethal. In effect, the researchers proved that human embryonic stem cells can differentiate through the T cell lymphoid lineage. They were also able to maintain a stable expression of the modified genes, at high levels, throughout the differenti- ation of stem cells.

HIV/AIDS
Male circumcision cuts risk
PLoS Med 2006;3:e262

In the first randomised controlled trial of its kind, male circumcision was recently shown to reduce the sexual transmission of HIV from women to men by about 60%. Now, researchers have used mathematical models to estimate the potential impact on health of extending circumcision to all men in sub-Saharan Africa.

The models predict that male circumcision could avert 2 million fresh HIV infections in the next decade and reduce deaths by 300 000. If extended another 10 years, 3.7 million additional infections and 2.7 million deaths could be prevented. The researchers argue that male circumcision is equivalent, therefore, to an inter- vention that reduces transmis- sion in both directions (between men and women) by 37%.

Molecular biology
Protein traffic as target for Parkinson's
Science 2006;313:324-8

Mutations in, or duplication of, asynuclein gene are associated with Parkinson's disease. Thanks to the preservation of genetic sequences through evolution, researchers attempted to eluci- date the role of asynuclein in yeasts and have found some interesting results.

Firstly, multiple copies of the gene reduced the viability of yeast cells. Increased expression of the gene puts considerable stress on the endoplasmic reticulum, within which the proteins fold.

When misfolded proteins build up, they need to be trans- ferred to the cytoplasm through the vesicles of the Golgi complex, after which they are tagged with a protein complex called protea- some, a signal for destruction of the protein. A complicated series of experiments show that excess asynuclein, due to mutations or duplications, affects this crucial vesicular transport. Genes that promote such vesicular transport have also been discovered. Whether this will offer novel targets for treatments for Parkinson's disease remains to be seen.

Internal medicine
Pain links head and heart
JAMA 2006;296:283-91

Migraine with aura is an estab- lished risk factor for stroke. Now, an analysis of 10 years' prospec- tive data from the women's health study shows a clear associ- ation between migraine with aura and a range of cardiovas- cular outcomes, including ischaemic heart disease.

The women in the study who said that they had migraine with aura were twice as likely as women without a history of migraine to have a heart attack (adjusted hazard ratio 2.08), angina (1.71), or coronary revas- cularisation (1.74) in the 10 year follow-up. Women were also twice as likely to die from ischaemic cardiovascular disease. Migraine without aura, however, was not associated with any cardiovascular outcome.

While researchers continue to unravel the complex relations between migraine and the human cardiovascular system, the remaining majority can be reassured.