For a beholder who is an evolutionary biologist, the eye is has long been a fascinating puzzle because of the many parts that must seamlessly work together for the whole to work properly. Biologists have addressed the question of ocular evolution with comparisons between different species, or macroevolutionary studies, and shown how the evolutionary process can be broken down into discrete steps through which a simple light-sensitive cell can evolve into a complex, multicomponent eye through adaptation.

A new study reveals that many European hospitals fail to routinely test people who may be at risk of an HIV-infection. If tests were more widely offered in the healthcare system, fewer HIV-patients would go unnoticed, especially in Northern Europe.

When a patient is admitted to hospital with a disease that could indicate an HIV-infection, they are not always offered an HIV-test. However, if offered a test, almost all patients accept, as revealed in the currently largest study on the subject, which has just now been published in the renowned scientific journal, PlosOne.

Research efforts on the intestine have increased in recent years. Owing to its enormous surface area - comparable to that of a one-bedroom apartment - and the huge number of neurons it contains - comparable to that in the brain - the intestine is sometimes referred to as the abdominal brain. In addition to absorbing nutrients from the foods we eat, it influences our immune status and metabolism.

With the help of sensors, specialized cells in the intestinal wall determine which hormones, if any, should be released into the bloodstream. Overall, it acts as a highly sophisticated control center.

How an organoid grows from cells

CORVALLIS, Ore. - Researchers in the College of Engineering at Oregon State University have discovered a new approach to "vitrification," or ice-free cryopreservation, that could ultimately allow a much wider use of extreme cold to preserve tissues and even organs for later use.

The findings were announced today in PLOS ONE, in work supported by the National Science Foundation.

"This could be an important step toward the preservation of more complex tissues and structures," said Adam Higgins, an associate professor in the OSU School of Chemical, Biological and Environmental Engineering, and expert on medical bioprocessing.

Scientists have mapped out the genes that keep our cells alive, creating a long-awaited foothold for understanding how our genome works and which genes are crucial in disease like cancer.

A team of Toronto researchers, led by Professor Jason Moffat from the University of Toronto's Donnelly Centre, with a contribution from Stephane Angers from the Faculty of Pharmacy, have switched off, one by one, almost 18,000 genes -- 90 per cent of the entire human genome -- to find the genes that are essential for cell survival.

The data, published in Cell on November 25, revealed a "core" set of more than 1,500 essential genes. This lays the foundation for reaching the long-standing goal in biomedical research of pinpointing a role for every single gene in the genome.

Proteins are often referred to as the building blocks of life, and make up about 15 per cent of the mass of the average person, performing a wide variety of essential functions in the body.

Scientists have long speculated about the nature of the dark proteome, the area of proteins that are completely unknown, but a recent study by CSIRO has mapped the boundaries of these dark regions, bringing us one step closer to discovering the complete structure and function of all proteins.

The work, led by Dr Sean O'Donoghue, a data visualisation scientist with CSIRO and the Garvan Institute, has been published today in the prestigious Proceedings of the National Academy of Sciences journal.