Disease resistance successfully spread from modified to wild mosquitoes.

Disease resistance successfully spread from modified to wild mosquitoes. Using genetically modified (GM) mosquitoes to reduce or prevent the spread of infectious diseases is a new but rapidly expanding field of investigation. Among the challenges researchers face is ensuring that GM mosquitoes can compete and mate with their wild counterparts so the desired modification is preserved and spread in the wild population. Investigators at Johns Hopkins University have engineered GM mosquitoes to have an altered microbiota that suppresses human malaria-causing parasites. These GM mosquitos preferred to mate with wild mosquitoes and passed along the desired protection to many generations of offspring. The research was funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.T he researchers genetically modified Anopheles mosquitoes, which in nature spread the malaria-causing parasite Plasmodium. The team caged equal numbers of wild and GM mosquitoes and monitored their breeding over 10 generations. Ninety percent of the offspring in each generation passed along the GM trait. Even when combining 10 percent GM with 90 percent wild mosquitoes, the Plasmodium-resistance trait dominated after a few generations. Importantly, the GM mosquitoes maintained their resistance to the malaria parasite for 7 years. GM

Prevention methods for dog bites too simplistic.

Prevention methods for dog bites too simplistic. Scientists at the University of Liverpool have shown that educating pet owners about canine body language may not be the answer to preventing dog bites as originally thought. Experts have argued that dog bites are preventable if owners are properly educated on how to read canine behaviour and identify high risk situations. Until now, however, the effectiveness of this theory has not been evaluated in any great depth. At a time when data suggests dog bite incidents are increasing, the team at Liverpool interviewed victims of dog attacks to gain further understanding into their perceptions of the experience.They found that in some cases there was no interaction with the dog before the bite occurred and therefore no opportunity to assess behaviour. There was a common tendency for victims to blame themselves for the attack, rather than the animal, or in cases where the dog was not known to them, they blamed the dog owner. continue

The hormone that could be making your dog aggressive discovered.

The hormone that could be making your dog aggressive discovered.Thousands of people are hospitalized every year for dog bites, and aggressive behavior is a major reason dogs end up in shelters. Biologists have studied the biology behind canine aggression, specifically the role of the hormones vasopressin and oxytocin. For some dog owners, a leisurely walk can turn stressful the moment their canine companion sees another pup walking by. Dogs with what is known as "leash aggression" may bark, growl or lunge at other dogs during walks, setting the scene for a tense and potentially dangerous interaction. So why do some dogs lash out on the leash while others don't? Hormones may be to partly to blame, according to new research led by the University of Arizona's Evan MacLean. Although a number of studies have looked at the role of testosterone and serotonin in aggression in dogs and other mammals, those hormones may be only part of the story, according to MacLean's findings, which are published in a special issue of the journal Frontiers in Psychology. MacLean and his collaborators looked specifically at oxytocin and vasopressin -- hormones that are also found in humans -- and found that they may play an important role in shaping dogs' social behavior.

Fecal transplant success for diabetes might depend on the recipient's gut microbes.

Fecal transplant success for diabetes might depend on the recipient's gut microbes.A small clinical trial in the Netherlands found that a fecal transplant from a lean donor can temporarily improve insulin resistance in obese men -- but only half of the recipients responded. Upon further investigation, the researchers discovered that they could predict the success of the treatment by analyzing each patient's fecal gut-bacterial makeup. This understanding could help shape the development of personalized fecal transplant for diabetes. Six weeks after participants received fecal material from a lean donor, half of them saw an improvement in insulin sensitivity, whereas the other half saw no change. "The fifty-fifty responder-to-non-responder rate surprised me," says Nieuwdorp. "I thought we would have fewer people respond to the transplant." The researchers then compared the pre-treatment microbiota of both groups and found that the non-responders were the ones who started off with less bacterial diversity. more

Gut bacteria metabolism may factor into hypertension.

Gut bacteria metabolism may factor into hypertension.One in three American adults suffers from high blood pressure, or hypertension. The disease can be passed down in families, and certain lifestyle factors such as smoking, high-sodium diets, and stress can increase the risk. In recent years, scientists have discovered that certain gut bacteria may contribute to hypertension, as well. In a few studies, when gut bacteria were killed off with antibiotics, patients with hypertension saw a drop in blood pressure. And when gut bacteria were transplanted from hypertensive people into normal mice, they developed high blood pressure. The evidence is compelling, but until now, scientists have not identified a mechanism to explain how bacteria increase blood pressure. more

How tuberculosis hides in the body.

How tuberculosis hides in the body.The tuberculosis vaccine only works for children. BCG (bacille Calmette-Guerin) doesn't protect you as an adult. Now we know more about how the bacterium avoids being detected. Tuberculosis bacteria hide in the very cells that would normally kill them. Now we know more about how they evade recognition. Tuberculosis affects millions of people worldwide. Treatment for it is often prolonged, from six months to two years. We thus have a lot to gain -- and save -- by finding better treatment methods. Improving our understanding about how the bacterium works is key to achieving this. Tuberculosis.

Beak Size always limits water consumption, regardless of environmental conditions.

Beak Size always limits water consumption, regardless of environmental conditions. The amount of water usage (WU) being recorded reflects two things going on in the bird house: water consumption (WC) and water spillage (WS). We noted this to emphasize that discharging more water at each drinker by increasing the water pressure doesn’t mean the birds will drink more, as they can only capture so much water in their beaks with each peck of the trigger pin. Drinkers discharging more water than bird beaks can hold simply results in more spillage. If the spillage reaches the point where the litter gets too wet, it creates an environment that can harm the bird (increased ammonia, pododermatitis, more disease challenges, among other things). The solution is to pay close attention to litter conditions and manage the water pressure in small increments until the litter has a less threatening moisture content (about 25 percent), which means less water is being spilled while the birds drink their fill. However, looking at this process a little closer, we can identify situations where excessive spillage may not always end up wetting the litter. Heat and different litter materials can be factors in keeping litter drier. But it is especially when ventilation fans are working hard in the summertime that any spillage can quickly evaporate, leaving the litter acceptably dry. Beak Size always limits water consumption, regardless of environmental conditions.