Knowledge Update

​New York, Nov 17 (IANS) Researchers in the US have developed a new ultra long-acting pill that can remain in the stomach for up to two weeks after being swallowed and aid in elimination of malaria.

The study found that the sustained therapeutic dose of a drug called ivermectin -- used to treat parasitic infections such as river blindness -- can also help keep malaria-carrying mosquitoes at bay.

In large animal models, the capsule safely stayed in the stomach, slowly releasing the drug for up to 14 days, and potentially providing a new way to combat malaria and other infectious diseases. 

This type of drug delivery could replace inconvenient regimens that require repeated doses. 

"Until now, oral drugs would almost never last for more than a day. The study opens the door to ultra-long-lasting oral systems, which could have an effect on all kinds of diseases, such as Alzheimer's or mental health disorders," said Robert Langer, Professor at Massachusetts Institute of Technology (MIT), US. 

The drug, designed by scientists at MIT and Brigham and Women's Hospital, is a star-shaped structure with six arms that can be folded inward and encased in a smooth capsule.

After the capsule is swallowed, acid in the stomach dissolves the outer layer of the capsule, allowing the six arms to unfold and stay in the stomach. Once the drug is released, the capsule could break down and pass safely through the digestive tract.

This is a platform into which you can incorporate any drug and can be used with any drug that requires frequent dosing. We can replace that dosing with a single administration, the researchers said.

Beijing, Nov 17 (IANS) China's manned spaceflight Shenzhou-11 began its return to the Earth on Thursday after separating from the Tiangong-2 space laboratory, where it had remained docked for the last one month.

The space capsule manned by astronauts Jing Haipeng and Chen Dong, disconnected from the Tiangong-2 at 4.41 a.m., and is scheduled to land on the Earth on Friday.

The Shenzhou-11 is expected to remain in space near the laboratory until it receives an order from the Beijing Aerospace Control Centre to re-enter the Earth's atmosphere and land, Efe news reported.

Jing and Chen departed aboard the Shenzhou-11 from the launch pad in Jiuquan in the Gobi desert on October 17 and docked at the space lab two days later.

Since then the astronauts have been working and living in the Tiangong-2 that was launched in September, and where they conducted several scientific experiments and advanced preparations for the operation of a future Chinese space station, which is expected to be fully operational by 2022.

The Tiangong-2 will remain in its orbit, some 393 km from the Earth's surface, until it docks with the Tianzhou-1, scheduled to be launched in April 2017.

New York, Nov 17 (IANS) Electronic cigarettes are as equally damaging to gums and teeth as conventional cigarettes, new research has found.

"We showed that when the vapours from an e-cigarette are burned, it causes cells to release inflammatory proteins, which in turn aggravate stress within cells, resulting in damage that could lead to various oral diseases," explained lead researcher Irfan Rahman, Professor at University of Rochester School of Medicine and Dentistry in the US.

Most e-cigarettes contain a battery, a heating device, and a cartridge to hold liquid, which typically contains nicotine, flavourings, and other chemicals. 

The battery-powered device heats the liquid in the cartridge into an aerosol that the user inhales.

Previously, scientists thought that the chemicals found in cigarette smoke were the culprits behind adverse health effects, but a growing body of scientific data, including this study published in the journal Oncotarget, suggests otherwise.

"How much and how often someone is smoking e-cigarettes will determine the extent of damage to the gums and oral cavity," Rahman said.

The study, which exposed 3-D human, non-smoker gum tissue to the vapours of e-cigarettes, also found that the flavouring chemicals play a role in damaging cells in the mouth.

"We learned that the flavourings -- some more than others -- made the damage to the cells even worse," Fawad Javed from University of Rochester Medical Center added.

"It's important to remember that e-cigarettes contain nicotine, which is known to contribute to gum disease," Javed said.

New York, Nov 17 (IANS) US researchers have developed a tiny, soft and wearable acoustic sensor that can measure vibrations in the human body, allows monitoring of human heart health as well as recognise speech.

The sensor, developed by researchers from the University of Colorado-Boulder and Northwestern University in the US, resembles a small band-aid, weighs less than one-hundredth of an ounce and can be mounted on nearly any surface of the body.

"This device has a very low mass density and can be used for cardiovascular monitoring, speech recognition and human-machine interfaces in daily life," said Jae-Woong Jeong Assistant Professor at University of Colorado-Boulder, in the paper published in the journal Science Advances. 

The new device can also pick up mechanical waves that propagate through tissues and fluids in the human body including the opening and closing of heart valves, vibrations of the vocal cords and even movements in gastrointestinal tracts.

"The thin, soft, skin-like characteristics of these advanced wearable devices provide unique capabilities for 'listening in' to the intrinsic sounds of vital organs of the body, including the lungs and heart, with important consequences in continuous monitoring of physiological health," said John Rogers, Professor at Northwestern University. 

While the sensor was wired to an external data acquisition system for the tests, it can easily be converted into a wireless device. 

Such sensors could be of use in remote, noisy places - including battlefields - producing quiet, high-quality cardiology or speech signals that can be read in real time at distant medical facilities, the researchers said.

Further, the speech recognition capabilities of the sensor also have implications for improving communication for people suffering from speech impairments, Jeong observed.

In the study, the researchers also showed vocal cord vibrations gathered when the device is on one's throat can be used to control video games and other machines. 

"While other skin electronics devices have been developed by researchers, what has not been demonstrated before is the mechanical-acoustic coupling of our device to the body through the skin," Jeong added. 

​Toronto, Nov 17 (IANS) A single bout of sleep apnea - a condition where breathing repeatedly stops and starts during sleep -- impacts your ability to regulate blood pressure, says a study.

Sleep apnea can result in frequent periods of decreased oxygen levels in the body, known as intermittent hypoxia.

Just six hours of the fluctuating oxygen levels associated with sleep apnea can begin to deteriorate a person's circulatory system, the study found.

"While it is well established that sleep apnea is linked to high blood pressure, our study shows this condition has an impact on the cardiovascular system that can begin within a single day," said researcher Glen Foster, Assistant Professor at University of British Columbia's Okanagan campus in Canada.

"After just six hours of fluctuating oxygen levels, similar to what happens with sleep apnea, the body's ability to regulate blood pressure is impaired," Foster noted.

"These changes occurred almost immediately in healthy young adults who were not experiencing the cumulative effects years of sleep apnea could bring about," Foster said.

As part of his study, Foster examined the impact of intermittent hypoxia on the cardiovascular system in a few healthy young adults. 

Study participants wore a ventilating mask for six hours and oxygen levels were altered to mimic sleep apnea symptoms.

The study, published in the American Journal of Physiology, found that sleep apnea compromised the function of a person's baroreceptors--biological sensors that regulate blood pressure. 

It also found damaging blood flow patterns in the legs, which over time could impact vascular health.

"These findings suggest that interventions for people suffering sleep apnea should occur as soon as the condition is diagnosed," Foster said.

​New York, Nov 17 (IANS) High doses of vitamin D are likely to reduce the incidence of acute respiratory illness in older adults, suggests a study led by an Indian-origin researcher.

The study found that among those who took higher doses of vitamin D, there was a 40 per cent reduction in acute respiratory illness -- one of the leading causes of serious illness, debilitation and death among patients in nursing homes and other long-term care facilities.

"Vitamin D can improve the immune system's ability to fight infections because it bolsters the first line of defense of the immune system," said lead author Adit Ginde, professor at the University of Colorado, Denver, US.

"This is a potentially life-saving discovery. There is very little in a doctor's arsenal to battle ARI, especially since most are viral infections where antibiotics don't work. But vitamin D seems able to potentially prevent these infections," Ginde added.

In older people that first line of defence is often impaired. But vitamin D can reinforce it and prevent illnesses like pneumonia, influenza and bronchitis, Ginde said.

It may also prevent infections and exacerbations of chronic obstructive pulmonary disease (COPD) like emphysema.

Conversely, Ginde found that those who received higher doses of vitamin D also saw an increase in falls. 

The falls were lower in those given smaller doses rather than higher monthly doses of vitamin D.

For the study, the team looked at 107 patients with an average age of 84 over a 12 month period. 

Those who received higher doses saw acute respiratory illness cut nearly in half, but also had over double the incidence of falls, the study said.

The study was published in the Journal of the American Geriatrics Society.

​Washington, Nov 17 (IANS) Scientists have discovered a "great valley" in the southern hemisphere of Mercury, providing more evidence that the small planet closest to the sun is shrinking.

Scientists used images from NASA's MESSENGER spacecraft to create a high-resolution topographic map that revealed the broad valley -- more than 1,000 kilometres long -- extending into the Rembrandt basin, one of the largest and youngest impact basins on Mercury. 

"Unlike Earth's Great Rift Valley, Mercury's great valley is not caused by the pulling apart of lithospheric plates due to plate tectonics; it is the result of the global contraction of a shrinking one-plate planet," said lead author of the study Tom Watters, senior scientist at the Smithsonian National Air and Space Museum in Washington, D.C. 

About 400 kilometres wide and three kilometres deep, Mercury's great valley is smaller than Mars' Valles Marineris, but larger than North America's Grand Canyon and wider and deeper than the Great Rift Valley in East Africa, said the study published in the journal Geophysical Research Letters.

Mercury's great valley is bound by two large fault scarps ? cliff-like landforms that resemble stair steps. 

The scarps formed as Mercury's interior cooled and the planet's shrinking was accommodated by the crustal rocks being pushed together, thrusting them upward along fault lines, the study said.

NASA's MErcury Surface, Space ENvironment, Geochemistry and Ranging (MESSENGER) mission was launched on August 3, 2004 to understand Mercury, the smallest, densest and least-explored of the terrestrial planets.

​Toronto, Nov 16 (IANS) Exercise may help improve gait, balance and reduce risks of falls in individuals living with Parkinson's disease, researchers say.

Parkinson's Disease -- a neurodegenerative disease that impacts movement, often including tremors -- affects nearly seven to 10 million persons around the world, according to the Parkinson's Disease Foundation. 

Despite the progressive nature of the disease, people living with Parkinson's disease can expect to improve their physical condition by being more physically active, the researchers said.

"Exercise should be a life-long commitment to avoid physical and cognitive decline, and our research shows that this is also true for individuals with Parkinson's disease," said Christian Duval, Professor at the Universite du Quebec a Montreal in Canada. 

The study found that exercise in Parkinson's disease patients majorly benefitted physical capacities -- strength, flexibility --, physical and cognitive functional capacities -- gait, mobility, cognitive functions.

The physical activity was also effective for limb strength, endurance, flexibility or range of motion, motor control, and metabolic function in patients with Parkinson's disease. 

Exercise showed nearly 67 per cent improvement in upper limb strength, the researchers explained. 

However, physical activity seems less efficient at improving clinical symptoms of Parkinson's disease -- rigidity, tremor, posture alterations -- and psychosocial aspects of life -- quality of life and health management --, with only 50 per cent or less of results reporting positive effects. 

The impact of physical activity on cognitive functions and depression also appeared weaker, the researchers reported the in the paper published in the Journal of Parkinson's Disease. 

​New York, Nov 16 (IANS) Adverse childhood experiences such as abuse or neglect, dysfunctional homes or low socio-economic status may be associated with a risk of poor blood pressure regulation, a study has found.

The study showed that children who experienced such adverse environments in early life were far more likely to have higher blood pressure at night as well as blood pressure variability over 24 hours.

In addition they are also prone to rapid onset of hypertension -- risk factor for cardiovascular disease -- at an earlier age.

"Adverse environments in early life have been consistently associated with the increased risk of hypertension in later life," said lead author Shaoyong Su, Associate Professor at the Augusta University in Georgia, US. 

Blood pressure variability has been linked to a number of problems in adults, including decreased brain function in older adults, as well as increased risk of stroke and poorer post-stroke recovery. Likewise, early-onset hypertension and prehypertension have been linked to adverse preclinical cardiovascular disease, including left ventricular hypertrophy and evidence of increased arterial stiffness.

For the study, the team conducted periodic around-the-clock blood pressure monitoring to capture day and nighttime pressure readings in 373 participants between the ages of seven and 38 during a 23-year period. 

Those who reported childhood adversity were 17 per cent more likely to have blood pressure higher than the clinical definition of hypertension during the daytime.

Most physicians focus on average blood pressure readings, but the new findings suggest that they should also ask younger patients about childhood adversity and watch for high blood pressure variability, Su noted.

The research was presented at the American Heart Association's Scientific Sessions 2016 in Louisana, US.