Immunology

Skin provides an essential protective barrier against foreign materials and pathogens and helps the body retain various fluids and electrolytes. When that barrier is damaged, the consequences can be devastating. Ulcers, bleeding and bacterial infections may result and the chances of these occurring increases the longer wounds remain open. 

Fortunately, epithelial cell sheets are self-repairing. The moment the integrity of the barrier is compromised, cellular mechanisms are initiated to close the gap. Cells begin crawling forward, and contractile cables are formed in the cells surrounding the wound to help pull the gap closed.

Bird flu: Livestock and farmers most at risk. Shutterstock

By Derek Gatherer, Lancaster University

By Joel N. Shurkin, Inside Science

(Inside Science) - In nature — the rule goes — everything is connected to everything else, so it is possible that when you combine two methods of preventing a deadly disease, bad things can happen.


There are up to 400 chemical compounds on human skin that could play a role in attracting mosquitoes. sookie, CC BY-SA

By Cameron Webb, University of Sydney

There’s always one in a crowd, a sort of harbinger of the oncoming mosquito onslaught: a person mosquitoes seem to target more than others. What is it about these unlucky chosen few that makes them mosquito magnets?

Some media, such as the New York Daily News and NBC, have reported that the Asian H5N1 strain of highly pathogenic avian influenza has now entered the United States. This is incorrect and they were told it was not the same strain by the United States Geological Survey and then suggested it was anyway.

There was avian flu that was recently found, in a green-winged teal in Washington state, but it is a different strain and is not known to harm humans nor has it been found in domestic poultry. 
If you are in the United States and travel to Mexico, you are cautioned not to drink the water, just like if you travel to Taiwan or China you are cautioned not to eat chicken bought from a street vendor; people are immune to some nasty stuff you probably are not.

Getting diarrhea in Mexico is called Montezuma's revenge - it means the natives are still getting back at the Spanish 500 years later and the rest of the world is thrown in for good measure. But it doesn't just end there. Taking antibiotics for diarrhea may put travelers visiting developing parts of the world at higher risk for contracting superbugs and spreading drug-resistant bacteria to their home countries.

Interbreeding of two malaria mosquito species in the West African country of Mali has resulted in a "super mosquito" hybrid that's resistant to insecticide-treated bed nets.

Anopheles gambiae, a major malaria vector, is interbreeding with isolated pockets of another malaria mosquito, A. coluzzii. Entomologists initially considered them as the "M and S forms" of Anopheles gambiae. They are now recognized as separate species. Interbreeding of two malaria mosquito species in the West African country of Mali has resulted in a "super mosquito" hybrid that's resistant to insecticide-treated bed nets.


It's not new that dwellers and cities are a little less hearty than rural cousins. There is even a hygiene hypothesis that says kids in the country get dirtier to their benefit and that wealthy, educated helicopter parenting and all those hand sanitizers and antibacterial soaps are doing more harm than good.

Allergies and numerous autoimmune diseases, such as asthma and type 1 diabetes, have become more common in the past 50 years, especially in urban environments. The belief is this is caused by urban issues like pollutants from human activities, a higher level of hygiene and the reduced biological diversity of the city living environment.
Maybe fat gets a bad rap. Immune responses matter but when it comes to skin infections, those response may depend greatly upon what lies beneath, according to a paper published in Science. Fat cells below the skin help protect us from bacteria, they write.

Richard Gallo, MD, PhD, professor and chief of dermatology at UC San Diego School of Medicine, and colleagues have uncovered a previously unknown role for dermal fat cells, known as adipocytes: They produce antimicrobial peptides that help fend off invading bacteria and other pathogens.

Methicillin-resistant Staphylococcus aureus (MRSA) infection has gotten a lot of attention. It is caused by a strain of staph bacteria that's become resistant to the antibiotics commonly used to fight it, but antibiotic resistance is not new. For as long as antibiotics have been manufactured (and nature shows evidence of it well before that) resistance evolves. 

Science has to stay a step ahead in the interests of public health and a new paper details a newly discovered antibiotic that eliminates pathogens without encountering any detectable resistance, which holds great promise for treating chronic infections like tuberculosis and those caused by MRSA.