What is Sneeze :
A sneeze is a sudden and forceful expiration of air through the nose or sometimes partly through the mouth. Its function is to clear the nasal passages of any irritants. However, sneezing is a common feature of various nasal disorders, even though no irritant is present in the nasal passages. This is seen in upper respiratory tract infections and allergic rhinitis, where the lining of the nasal cavity is inflamed due to infectious or immune-mediated factors. Sneezing in these cases does little to clear out the nasal passages but may pass out excessive nasal mucus (rhinorrhea), which is a concomitant feature.
Rapid inspiration fills the lung with extra air. The epiglottis and the vocal cords close tightly to build up pressure in the lungs. The expiratory muscles of respiration, as well as accessory respiratory muscles, contract forcefully. This further increases the pressure in the lungs. Once sufficiently high pressure is reached, the vocal cords relax, the epiglottis opens, and the air rushes out rapidly.
Decoding Sneeze reflex :
A small tickle in your nose, exposure to irritants, and viral infections can cause sneezing. But the cellular pathways and neurons behind them have been hardly understood. A new study has shown that a molecule named neuromedin B (NMB) was important for sneezing. When this molecule was blocked, the test mice did not sneeze despite being exposed to allergens. The researchers could also stimulate a sneeze reflex by exposing part of the mouse brain to the NMB peptide. - Published in Cells
Snail Survival Skills :
About 40 years ago, humans brought the North American rosy wolf snail to the island of Tahiti. This snail was a predator, and it led to the extinction of over 50 species of native snails. But surprisingly, one species survived, the white-shelled Partula hyalina. By sticking tiny sensors to the shells of the snail, scientists have understood how it survived. P. hyalina could tolerate more sunlight than its predator so that it could live undisturbed in the sunlit parts of the forest. - Published in Communications Biology
Methane Eating Microbes :
By studying sediments from seven seafloor seeps, researchers have found that these sites house several methane-oxidizing microbes. These microbial communities showed high rates of methane consumption. Lead author Jeffrey J. Marlow explains in a release that understanding these anaerobic methane-eating microbes can help in bioremediation in other situations like landfills with methane leaks. Published in PNAS
Bizarre Lizard :
By studying amber collected from Myanmar, researchers have described a new lizard that lived 99 million years ago. The team named it Oculudentavis naga. Oculudentavis is derived from oculus = eye, denotes = teeth, and avis = bird, and Naga is one of the many ethnic tribes living in the Burmese amber mines area. Published in Current Biology
Sediment Secrets :
An international team of researchers has now discovered several bacteria that use DNA as a food source. They were found in the sediments of the Atlantic Ocean. "From the bacteria's perspective, DNA is particularly nutritious," says Kenneth Wasmund, lead author of the study, in a release. "It's essentially a fertilizer. After all, it is a chain of millions of pieces of sugar and phosphorus- and nitrogen-containing bases." The team further studied the genomes of these species. - Published by Nature Microbiology
You must be logged in to post a comment.