Comment

Comment by Dr. Krishna Kumari Challa on October 4, 2016 at 6:02am

The 2016 Nobel Prize in Medicine goes to pioneering work on autophagy

The 2016 Nobel Prize in Medicine or Physiology was given to Yoshinori Ohsumi

 of the Tokyo Institute of Technology for basic research describing a fundamental housekeeping function of the cell—a process called autophagy. From the Greek for "self-eating," autophagy is the straightforward mechanism by which a cell digests certain large internal structures and semi-permanent proteins in a continual cleanup process. The process may have evolved as a response to starvation, in which cells cannibalized some of their own parts in order to continue living. But over the eons it has become an essential tool used by cells to maintain their own health, resist infection and possibly even fight cancer.

Autophagy is particularly important in cells such as neurons, which tend to live a long time and thus need to be constantly renewed and refurbished. The process takes place in the cytoplasm, the jelly-like fluid that fills the cell outside the nucleus. The workings of the cytoplasm are so complex . . . that it is constantly becoming gummed up with the detritus of its ongoing operations. Autophagy is, in part, a cleanup process: the trash hauling that enables a cell whose cytoplasm is clotted with old bits of protein and other unwanted sludge to be cleaned out." Problems with autophagy may contribute to neuronal damage in Alzheimer's, Parkinson's and other neurodegenerative diseases.

Ohsumi chose the transport of materials to the yeast vacuoles as his research project and got several awards for his pioneering work. Autophagy is fundamental to a cell's continued good health and have even specialized in describing particular types of autophagy—such as the digestion and degradation of worn-out mitochondria (the powerhouse of the cell) and the endoplasmic reticulum, which assembles, folds and delivers proteins to the rest of the cell.

Comment by Dr. Krishna Kumari Challa on October 1, 2016 at 6:12am

Galaxy made of dark matter? Among the thousand-plus galaxies in the Coma cluster, a massive clump of matter some 300 million light-years away, is at least one — and maybe a few hundred — that shouldn’t exist.

Dragonfly 44 is a dim galaxy, with one star for every hundred in our Milky Way. But it spans roughly as much space as the Milky Way. In addition, it’s heavy enough to rival our own galaxy in mass, according to results published in the Astrophysical Journal Letters at the end of August. That odd combination is crucial: Dragonfly 44 is so dark, so fluffy, and so heavy that some astronomers think it will either force a revision of our theories of galaxy formation or help us understand the properties of dark matter, the mysterious stuff that interacts with normal matter via gravity and not much else. Or both.

There are several theories going around in the Astronomy circles now about them. And people are trying to figure out things and find answers to the Qs 'why, what, how, whether etc.'.

Comment by Dr. Krishna Kumari Challa on September 28, 2016 at 8:00am

World's first baby born with 'three parents' reports New Scientist

A Jordanian couple has been trying to start a family for almost 20 years. Ten years after they married, she became pregnant, but it ended in the first of four miscarriages.

In 2005, the couple gave birth to a baby girl. It was then that they discovered the probable cause of their fertility problems: a genetic mutation in the mother’s mitochondria. Their daughter was born with Leigh syndrome, which affects the brain, muscles and nerves of developing infants. Sadly, she died aged six. The couple’s second child had the same disorder, and lived for 8 months.

Using a controversial “three-parent baby” technique , the boy was born on 6 April 2016. He is showing no signs of disease.

The boy’s mother carries genes for Leigh syndrome, a fatal disorder that affects the developing nervous system. Genes for the disease reside in DNA in the mitochondria, which provide energy for our cells and carry just 37 genes that are passed down to us from our mothers. This is separate from the majority of our DNA, which is housed in each cell’s nucleus.

Around a quarter of her mitochondria have the disease-causing mutation. While she is healthy, Leigh syndrome was responsible for the deaths of her first two children. The couple sought out the help of John Zhang and his team at the New Hope Fertility Center in New York City.

Zhang has been working on a way to avoid mitochondrial disease using a so-called “three-parent” technique. In theory, there are a few ways of doing this. The method approved in the UK is called pronuclear transfer and involves fertilising both the mother’s egg and a donor egg with the father’s sperm. Before the fertilised eggs start dividing into early-stage embryos, each nucleus is removed. The nucleus from the donor’s fertilised egg is discarded and replaced by that from the mother’s fertilised egg.

But this technique wasn’t appropriate for the couple – as Muslims, they were opposed to the destruction of two embryos. So Zhang took a different approach, called spindle nuclear transfer. He removed the nucleus from one of the mother’s eggs and inserted it into a donor egg that had had its own nucleus removed. The resulting egg – with nuclear DNA from the mother and mitochondrial DNA from a donor – was then fertilised with the father’s sperm.

Zhang’s team used this approach to create five embryos, only one of which developed normally. This embryo was implanted in the mother and the child was born nine months later. 

The team avoided destroying embryos, and used a male embryo, so that the resulting child wouldn’t pass on any inherited mitochondrial DNA. 

A remaining concern is safety. Last time embryologists tried to create a baby using DNA from three people was in the 1990s, when they injected mitochondrial DNA from a donor into another woman’s egg, along with sperm from her partner. Some of the babies went on to develop genetic disorders, and the technique was banned. The problem may have arisen from the babies having mitochondria from two sources.

When Zhang and his colleagues tested the boy’s mitochondria, they found that less than 1 per cent carry the mutation. Hopefully, this is too low to cause any problems; generally it is thought to take around 18 per cent of mitochondria to be affected before problems start.

The child will be monitored and we need more of these cases to judge teh effectiveness of this technique. 

Comment by Dr. Krishna Kumari Challa on September 27, 2016 at 6:47am

Egyptian researchers have developed a bandage embedded with nanoparticles for the treatment of wounds using the anti-epilepsy drug Phenytoin, known for its capacity to treat skin injuries.

The bandage can heal wounds in a few days, after just one application to soft tissue. Wounds normally take several days to a few weeks to heal completely, and some may only heal after several months or up to two years.

Even though Phenytoin is known for its potential to accelerate wound healing, some of its properties limit its effectiveness. For example, a low percentage of the drug can be absorbed into the blood circulation. It also doesn’t cover the entire wounded area, which interferes with the efficiency of healing.

To overcome these challenges, a research team from Zewail City of Science and Technology in Egypt, led by Ibrahim M. El-Sherbiny, the director of the Center for Materials Science, embedded the drug into a bandage consisting of nanoparticles carried on nanofibers.
“This allowed a well-controlled release of phenytoin, distributing it effectively, which, boosts its efficiency.”

The results of the study, published last May in the Journal of Applied Materials & Interfaces, also confirmed an improvement in the formation of granulation tissue — a fibrous connective tissue which grows from the base of the wound until it fills it, and replaces the blood clot that formed after the wound was received.

Comment by Dr. Krishna Kumari Challa on September 21, 2016 at 10:19am

A Failed Supernova

A star that mysteriously disappeared might be the first confirmed case of a failed supernova, a star that tried to explode but couldn’t finish the job. A newborn black hole appears to have been left behind to snack on the star’s remains.

In 2009, a star in the galaxy NGC 6946 flared up over several months to become over 1 million times as bright as the sun. Then, it seemed to vanish. While the star could just be hiding behind a wall of dust, new observations with the Hubble Space Telescope, reported online September 6 at arXiv.org, strongly suggest that the star did not survive. A faint trickle of infrared light, however, emanates from where the star used to be. The remnant glow probably comes from debris falling onto a black hole that formed when the star died.

Black holes are typically thought to form in the aftermath of a supernova, the explosive death of a massive star. But multiple lines of evidence have recently hinted that not all heavyweights go out with a bang. Some stars might skip the supernova and collapse into a black hole. Until now, though, evidence that this happens has been either spotty or indirect.

“This is the first really solid observational evidence for a failed supernova".

Comment by Dr. Krishna Kumari Challa on September 21, 2016 at 10:08am

Strange it may seem but according to a new study Camouflaging Octopi & Squids Are Colourblind!

Several cephalopods manage to blend beautifully with their surroundings, but they themselves are actually colorblind, finds a new study published in Proceedings of the Royal Society B. Cephalopods—cuttlefish, squid and octopus—are renowned for their fast color changes and remarkable camouflage abilities. Previous investigations of vision and visual pigment evolution in aquatic predators, however, have focused on fish and crustaceans, generally ignoring the cephalopods. Soft-bodied cephalopods are attractive for studying the evolution of vision as they have camera-like eyes, sharing many similarities in optics, anatomy and function with fish. According to Professor Justin Marshall and Dr. Chung Wensung from the Queensland Brain Institute, the goal of the study was to investigate how these creatures adapt to the light conditions in different habitats. The researchers found that squids have the ability to adapt their vision depending on the color and depth of the water they live in. This ability is called evolved spectral tuning, as they can change their visual focus from green, in coastal waters, to blue, to match deep sea conditions. “These engaging and charismatic animals can display complex, bright color patterns on their skin, but our studies have reconfirmed beyond doubt that they are colorblind,” Marshall said. “It is ironic then that humans still struggle to spot them in the natural habitat where their camouflage is perfectly matched with the surroundings.” Marshall said this latest research into cephalopods provided fascinating insights into how the remarkably intelligent creatures interacted with their world. 

http://rspb.royalsocietypublishing.org/content/283/1838/20161346

Comment by Dr. Krishna Kumari Challa on September 20, 2016 at 8:06am

Great News!

France just became the first country to ban all plastic plates, cups, and utensils.

With reports like 'By 2050, there'll be more plastic than fish in our oceans'*, we feel disheartened. But France has shown a way to tell us that need not be the case.

France just passed a law that says all plastic plates, cups, and utensils will be banned by 2020, and replacements will need to be made from biologically sourced materials that can be composted. 

The new law follows a total ban on plastic shopping bags in July, and is part of the country’s Energy Transition for Green Growth Act - a plan to make France a world leader in adopting more environmentally friendly practices, and in reducing greenhouse gas emissions.

According to the new law, the distribution of disposable plastic bags at supermarket check-outs has been banned as of July, and plastic bags will be prohibited in fruit and vegetable departments from 1 January 2017.

A ban on the distribution of disposable cooking utensils, cups, and plates will be enforced in 2020, which will give manufacturers time to adjust.

Local ministers stipulated that in three years’ time, 50 percent of the material used to procure such items will have to be organic and compostable, and that proportion will rise to 60 percent by 2025.

The news has been welcomed by conservation groups around the world, and with predictions that by 2050, there'll be more plastic than fish in our oceans, is the kind of definitive action that’s needed if we’re going to have any chance of mitigating the problem of waste in a growing global population. 

* http://www3.weforum.org/docs/WEF_The_New_Plastics_Economy.pdf

Comment by Dr. Krishna Kumari Challa on September 20, 2016 at 7:53am

Comment by Dr. Krishna Kumari Challa on September 20, 2016 at 6:43am

Filtering sea water in minutes!

• The technology is based on salt-attracting membranes and vaporising heat

• The membranes are made of cellulose acetate powder which is cheap to make

• Even remote communities could use the technique – with just membranes and fire.

Researchers at Alexandria University in Egypt have unveiled a cost-effective desalination technology which can filter highly salty water in minutes.

The technology is based on membranes containing cellulose acetate powder, produced in Egypt. The powder, in combination with other components, binds the salt particles as they pass through, making the technique useful for desalinating seawater. 

The membrane we fabricated can easily be made in any laboratory using cheap ingredients, which makes it an excellent option for developing countries.

The technology uses pervaporation, a technique by which the water is first filtered through the membrane to remove larger particles and then heated until it vaporises. The vapour is then condensed to get rid of small impurities, and clean water is collected.

This method can be used to desalinate water which contains different types of contamination, such as salt, sewage and dirt. This kind of water is difficult to clean quickly using existing procedures.

Desalination of simulated seawater by purge-air pervaporation using an innovative fabricated membrane

http://wst.iwaponline.com/content/72/5/785

Comment by Dr. Krishna Kumari Challa on September 17, 2016 at 7:20am

• ‹ Previous
• 1
• …
• 632
• 633
• 634
• 635
• 636
• …
• 839
• Next ›
• Page