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Comment by Dr. Krishna Kumari Challa on April 20, 2018 at 6:58am

Plants repair their Sun -damaged DNA: If the ultraviolet radiation from the sun damages human DNA to cause health problems, does UV radiation also damage plant DNA? The answer is yes, but because plants can’t come in from the sun or slather on sunblock, they have a super robust DNA repair kit.

Research finds that this powerful DNA repair system in plants closely resembles a repair system found in humans and other animals.

The study, which appears in Nature Communications, is the first repair map of an entire multicellular organism. It revealed that the “nucleotide excision repair” system works much more efficiently in the active genes of plants as compared to humans. And this efficiency depends on the day/night cycle.

Excision repair,  is now widely viewed as the major mechanism of DNA repair—including repair of UV damage—in living organisms. 

The researchers performed XR-seq scans on cells from UV-exposed plants—Arabidopsis thaliana, the “lab rat” of plant research also known as thale cress or mouse-ear cress. The resulting repair maps revealed that excision repair in Arabidopsis works faster on genes that are active. Genes when active are transcribed into strands of RNA that may then be translated into proteins, the main machinery of cells. Prior studies from the Sancar lab showed that excision repair works more efficiently for actively transcribed genes in animals and bacteria. The phenomenon, called transcription-coupled repair, is thought to have evolved as a way to direct DNA repair where it is most acutely needed.

The researchers performed XR-seq on UV-exposed Arabidopsis over 24-hour periods to discover that the efficiency of transcription-coupled repair also varies according to the “circadian” day/night cycle for 10 to 30 percent of Arabidopsis‘s genes. This reflects the normal daily variations of transcription activity in these genes.

https://www.nature.com/articles/s41467-018-03922-5

Comment by Dr. Krishna Kumari Challa on April 19, 2018 at 8:25am

Evidence of a planet getting destroyed in our solar system...

An asteroid that slammed into the Sudan desert on Oct. 7, 2008, shot out lots of little space rocks holding a precious secret: diamonds that likely formed billions of years ago inside the embryo of a now-decimated planet.

That lost planet was the size of Mercury or perhaps Mars, researchers now say.

An asteroid that slammed into the Sudan desert on Oct. 7, 2008, shot out lots of little space rocks holding a precious secret: diamonds that likely formed billions of years ago inside the embryo of a now-decimated planet.

That lost planet was the size of Mercury or perhaps Mars, researchers now say.

In the space rocks, which are also called meteorites, researchers found compounds common to diamonds on Earth, such as chromite, phosphate and iron-nickel sulfides. It's the first time these diamond components have been found in an extraterrestrial body, the researchers said in a new study describing the findings.

The finding provides more information on the early days of our solar system about 4.4 billion years ago, when the zone near the sun had several planetary embryos. Many of them coalesced into the planets we see today. Others fell into the sun or were ejected into interstellar space.

The meteorites were formed after an asteroid slammed into Earth's atmosphere — making it technically a meteor — exploding 23 miles (37 kilometers) above the Nubian Desert in Sudan. The explosion from the 13-foot-wide (4 meters) body shot fragments all over the desert below. Researchers picked up 50 of these pieces, which ranged in size from 0.4 to 4 inches (1 to 10 centimeters).

Researchers collected these tiny meteorites into a collection called "Almahata Sitta"; this is the Arabic word for "Station Six," a train station nearby the meteorite fall and between Wadi Halfa and Khartoum. After collecting the tiny meteorites, researchers discovered nano-size diamonds inside them. But at first, the origins of the diamonds eluded researchers.

Nanodiamonds can form from "normal" static pressure inside a large parent body like Earth, but there are other origin theories as well. High-energy collisions between worlds in space can leave such diamonds behind, as can deposition by chemical vapor,according to a statement from the Federal Polytechnic School of Lausanne in Switzerland.

The new study, however, revealed that the diamonds in the meteorite could form only under pressures higher than 20 gigapascals. This is an extremely high form of pressure that humans can generate with certain explosives.

"This level of internal pressure can only be explained if the planetary parent body was a Mercury- to Mars-sized planetary 'embryo,' depending on the layer in which the diamonds were formed," the researchers said 

That planetary embryo would have then been destroyed through violent collisions, the researchers noted.

The research was published online (April 17) in the journal Nature Communications.

Comment by Dr. Krishna Kumari Challa on April 17, 2018 at 9:43am

Plastic degrading  enzyme created by scientists...

Scientists have created a substance capable of “eating” plastic that could help tackle the world’s pollution problem.

The substance is based on an enzyme – a “biological catalyst” – first produced by bacteria living in a Japanese recycling centre that researchers suggested had evolved it in order to eat plastic.

Dubbed PETase for its ability to break down the PET plastic used to make drinks bottles, the enzyme accelerated a degradation process that would normally take hundreds of years.

Fine-tuning this naturally produced enzyme allowed a research team to produce something capable of digesting plastic more effectively than anything found in nature.

By breaking down plastic into manageable chunks, the scientists suggest their new substances could help recycle millions of tonnes of plastic bottles.

Plastic is notoriously resistant to natural degradation, and the discovery of the Japanese plastic-eating bacteria in 2016 was heralded by experts and commentators alike as a potential natural solution to plastic pollution.

While attempting to verify these claims, University of Portsmouth biologist Professor John McGeehan and his colleagues accidentally created a super-powered version of the plastic-eating enzyme.

During an investigation of the enzyme’s structure, the scientists made a slight tweak to the part thought to be involved with plastic digestion.

Doing so ramped up the ability of the enzyme to degrade PET, and also gave it the ability to degrade an alternative form of PET known as PEF.

Comment by Dr. Krishna Kumari Challa on April 14, 2018 at 5:42am

European Space Agency maps second magnetic field around Earth.

A second layer of the magnetic field has been found  around the earth. According to the reports, the magnetic field was discovered by the trio of satellites which were used to study the magnetic fields.

The mission was named “Swarm” which was launched in the year 2013. Four years of continuous efforts have proved fruitful, a lot of data was collected and as a result, it contributed to the mapping of the latest discovery in the world of space technology. The satellites revolve around the earth at 300-530 km.

 The newly discovered magnetic field is about 2-2.5 nanotesla at the satellite altitude which is about 20,000 times weaker than the earth’s existing magnetic field. The scientist stated that they have used Swarm to measure the magnetic signals of the tides from the ocean surface to the seabed.

Getting on the practical aspect of the newly discovered magnetic field it could be used to hone the models of global warming by naming the monitoring patterns of the heat energy as they change their positions globally. But in addition to this, the tidal magnetic signal also induces a weak magnetic response under the deep seabed. The findings will be further used to study the electrical properties of the earth lithosphere as well as the upper mantle.

Comment by Dr. Krishna Kumari Challa on April 13, 2018 at 9:10am

WE ARE MARCHING FOR SCIENCE ON 14th  APRIL, 2018.

( We are part of Global March For Science)

Come join us and make it a great success

Hyderabad venue: Press club, Basheerbagh

Starts at 10 am.

Our demands...

• 1. Allocate at least 3% of GDP to scientific and technological research and 10% towards education
• 2. Stop propagation of unscientific, obscurantist outdated ideas, and develop scientific temper, human values and spirit of inquiry in conformance with Article 51A of the Constitution.
• 3. Ensure that the education system does not impart ideas that contradict scientific evidence.
• 4. Enact policies based on scientific evidence.

https://www.marchforscience.com/

http://breakthrough-india.org/MFS2018/

Comment by Dr. Krishna Kumari Challa on April 12, 2018 at 8:17am

Scientists here say Dog is a biodiversity enemy

According to a new study, Canis lupus familiaris (dog, for short) is  an ‘invasive’ species in many ecosystems! Like the Japanese kudzu vine or the infamous Lantana, dogs are a non-native introduced species that are wreaking havoc on the ecological balance of many sensitive ecosystems. Now, a study by researchers from the Ashoka Trust for Research in Ecology and the Environment explores the effect of free-ranging dogs, or strays, on their surroundings in India.

Previous studies have shown that domesticated dogs have imperilled 188 threatened species of animals and caused 11 mass extinctions, globally! Domestic dogs have been considered as invasive mammalian predators. After cats and rodents, they are the third most damaging invasive predators.

In countries like India, where the population of stray dogs are surging by the day without checks and bounds by a governing body, these dogs turn feral—a state in which they are neither truly wild not truly domesticated. “Unlike cats and rats which perhaps target smaller sized animals, feral dogs can target a larger range of prey size as predators as they can hunt in packs. Their impacts are as detrimental as cats and rats, though cats and rats have reported higher extinction for biodiversity.

The study shows that the threat from dogs on wildlife is real and could come in the way of conservational efforts. So, what can we do to curb this conflict? Managing dog population is the key, say the researchers.

 The researchers opine that in order to protect local wildlife and ensure a good quality of life for dogs, carefully planned population control programs should be implemented near protected forest areas.

Domesticated dogs are adding a new dimension to the threats many species of wildlife are already facing due to habitat loss, deforestation, encroachment, etc. Man’s best friend is turning out to be biodiversity’s biggest enemy, as this research shows.

https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/acv...

Comment by Dr. Krishna Kumari Challa on April 10, 2018 at 3:03pm

Eating very hot chillies might trigger reversible cerebral vasoconstriction syndrome — a temporary narrowing of arteries in the brain.

His is the first known instance of reversible cerebral vasoconstriction syndrome — a temporary narrowing of arteries in the brain — to be tied to eating a hot pepper, researchers report April 9 in British Medical Journal Case Reports. Such narrowed arteries can lead to severe pain called “thunderclap headaches” and are often associated with pregnancy complications or illicit drug use.

During a hot-pepper-eating contest, the man ate a chili dubbed the Carolina Reaper, named by Guinness World Records as the hottest pepper in the world. The Carolina Reaper is over 200 times as spicy as a jalapeño. About a minute later, he reported experiencing splitting headaches that came and went over two days before he sought treatment.

Initial tests failed to find anything out of the ordinary. But a CT scan of blood vessels in the man’s brain showed severely narrowed arteries. After treatment, including hydration and pain medication, the headaches stopped. When the researchers imaged his brain five weeks later, the arteries had returned to their normal size.

 http://casereports.bmj.com/content/2018/bcr-2017-224085

Comment by Dr. Krishna Kumari Challa on April 5, 2018 at 8:40am

Cancer is a dreaded disease. And chemotherapy has its pitfalls but becomes unavoidable sometimes. But how about making chemotherapy more safer and effective?

That is exactly what researchers at the Indian Institute of Technology Kanpur have proposed - a new model for the transport of anti-cancer drugs to human brain tumours using liposomes—a small sac-like structure that transports nutrients in our cells. 

Liposomes, like our cell membranes, are made of molecules called phospholipids. In a cell membrane, these molecules are arranged into two layers. However, in a liposome, the two layers meet to form a hollow sphere filled with water. In this study, the researchers propose to replace the water in the empty area with anti-cancer drug molecules—a technique they claim improves transport of the drug molecules—to create a nanosized drug delivery system.

Besides, the lipid layer in the liposomes acts as a protective coat and prevents the anti-cancer drug from affecting healthy cells. Since these liposomes are in the bloodstream, they circulate for longer and collect at the tumour site, helping more of the drug reach their target cells. This approach causes less damage to the healthy cells of the body.

There is another aspect of tumours that makes it hard to use anti-cancer drugs in treatment without damaging the surrounding healthy cells. Tumorous cancer cells vary in their organisation, function and structure, making it difficult for drugs to target them specifically.  Also, the veins and arteries that supply blood to a tumour, twist and coil, making it more difficult to administer the anti-cancer drug into a tumour. Since the endothelial cells present in the tumour blood vessels are widely spaced out, drugs tend to leak out into the interstitial spaces between the cells, reducing the efficacy of the drugs.

The researchers analysed the structure of blood vessels of the cancerous brain tissue using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) by taking multiple snapshots of the tumor vasculature over a period of time and comparing them. Using this data, they predicted the transport, accumulation and efficacy of the chemotherapeutic drug in a tumour with computational fluid dynamics—a branch of fluid mechanics that uses numerical analysis and data structures to solve and analyse problems that involve fluid flows. They also predicted the distribution of the drug in a tumour. “With the help of this model, we can predict the preferential deposition of chemotherapeutic drugs inside a tumour, thus predicting the healing of a tumour for a specific patient, provided we have the initial medical images of that patient".

The results of the study showed that a high amount of the anti-cancer drug Doxorubicin, which was not encapsulated by a liposome, accumulated in the interstitial spaces between tumour cells. This accumulation could potentially cause adverse side-effects like swelling, reddening and peeling of skin from the hands and feet. In contrast, the liposome-encapsulated drug remained inside a tumour for a longer time. They also found that the high concentration of liposome-coated drug aggregated at the tumour site and increased the therapeutic efficiency of the liposomal anticancer drug.

Medical imaging of the tumours helps predict the deposition of the anti-cancer drug in a tumour for a patient and look for chemotherapeutic drug options that could better suit him/her. This ability also allows doctors to develop a specific chemotherapeutic approach for each patient, based on the structure of their brain tumour and the blood vessels surrounding it.

http://biomechanical.asmedigitalcollection.asme.org/article.aspx?ar...

Comment by Dr. Krishna Kumari Challa on March 14, 2018 at 9:36am

World renowned physicist Stephen Hawking has died at the age of 76.

He died peacefully at his home in Cambridge in the early hours of Wednesday, his family said.

The Briton was known for his work with black holes and relativity, and wrote several popular science books including A Brief History of Time.

At the age of 22 Prof Hawking was given only a few years to live after being diagnosed with a rare form of motor neurone disease.

Comment by Dr. Krishna Kumari Challa on March 14, 2018 at 9:01am

Newer drugs make hepatitis C-positive kidneys safe for transplant

Improved antivirals could help expand the number of organs available for donation

People who received kidneys from donors infected with hepatitis C did not become ill with the virus, thanks to treatment with newer drugs that can cure the disease, a small study reports.

Ten patients not previously infected with hepatitis C took doses of powerful antiviral medications before and after receiving the transplants. None of the patients developed chronic infections, researchers report online March 6 in the Annals of Internal Medicine. The finding could help make more kidneys available for transplants.

C. Durand et al. Direct-acting antiviral prophylaxis in kidney transplantation from .... Annals of Internal Medicine. Published online March 6, 2018. doi:10.7326/M17-2871.

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