City birds stress less

Unlike their wild cousins, urban birds have been found to have a reduced response to stress in order to cope better with numerous city strains without suffering deleterious chronic effects. Ornithologists of the Max Planck Institue in Germany measured blood levels of corticosterone, the stress hormone in birds, after standardized capturing and handling stressor protocols applied during the birds’ first autumn, winter, and spring. Both urban and wild birds showed similar hormonal stress response during the first autumn, but the stress response was distinctly lower in urban birds as compared to wild birds during the first winter and spring. According to the researchers, these results show that city life leads to changes in physiological coping mechanisms that are necessary for the survival of the wild animals in a urban dwelling.

Source: Ecology

-Mayce Al-Sukhni

Carbon monoxide may save lives

Women who smoke during pregnancy have a reduced chance of developing pre-eclampsia, a pregnancy-related disorder usually characterized by hypertension and high concentrations of protein in urine. The disorder is characterized by a failure of the growing fetus to receive adequate amounts of nutrients due to oxidative damage to syncytiotrophoblast cells of the placenta. These cells are essential to development as they provide nutrient transfer from the mother to the fetus.

In a study conducted by scientists at Queen’s University, placental tissue obtained from non-smoking women were subjected to oxidative stress, resulting in syncytiotrophoblast cell death. In comparison, tissues then treated with carbon monoxide (at levels similar to smoking mothers) were found to have a significant decrease of syncytiotrophoblast cell death. The carbon monoxide treated samples also showed syncytiotrophoblasts without signs of cell injury. Although the frequency of pre-eclampsia is reduced in smoking mothers, there are more imminent problems associated with smoking during pregnancy, such as low birth weight and Sudden Infant Death Syndrome. Nevertheless, carbon monoxide treatments give promising applications for organ transplantation, which are threatened by oxidative stress.

Source: American Journal of Pathology

-Jennifer Huen

New dogs but old tumour

Scientists at University College London and the University of Chicago have recently discovered that the canine transmissible venereal tumour (CTVT) is between 250 and 2,500 years old, a finding that links the cancer to an ancestral cancer in wolves. Dogs can transmit CTVT to other dogs through copulation, licking, biting, and smelling. Unlike other cancers that develop over time, CTVT is spread by the transmission of tumour cells themselves. By collecting tumour samples from various dog breeds internationally, researchers found that all the tumours shared the same genetic marker that were absent in each breed’s non-cancerous cells. Further analysis showed that the DNA sequence between all the tumours were identical but unique from the non-cancerous canine cells, regardless of how distinct the dogs were from each other. After conducting computational studies, the researchers believe that these tumour cells originated from wolves at least two centuries ago and were then “passed down” to present-day breeds of dogs.

Source: Cell

-J.H.

It’s a dirty job…

Scientists have developed a way to make laundry detergents even more powerful at removing stains. Enzymes are included in detergents to help target protein-based stains in laundry. However, these enzymes often are susceptible to clumping and inactivation by air and moisture, as well as other detergent ingredients. To keep the enzymes active for as long as possible, scientists have designed silica gel beads that encapsulate the enzymes and protect them from inactivation. The coating remains intact until conditions are right in the washing machine, at which point the enzymes are released to act on the dirty laundry.

Source: Chemistry of Materials

-M.A.