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Comment by Dr. Krishna Kumari Challa on October 8, 2015 at 5:29am

DNA Repair Methods gets 2015 Chemistry Nobel Prize

Three scientists who found ways that cells fix damaged DNA—staving off cancer and other diseases—have won this year's prize
The coveted prize has gone to Tomas Lindahl from the Francis Crick Institute and Clare Hall Laboratory in Hertfordshire, England; Paul Modrich from the Howard Hughes Medical Institute and Duke University School of Medicine in North Carolina in the United States; and Aziz Sancar from the University of North Carolina in Chapel Hill, also in the U.S.
All the researchers, working independently over the last 40 years, described three different mechanisms that create errors in DNA—the molecule that controls cell behavior—and the different ways that chemical and biological processes fix many of these problems.

All forms of cancer start with DNA damage. If you do not have DNA repair, we would have a lot more cancer. That’s how important this is.
The understanding that we have of these mechanisms help us design drugs to repair all sorts of DNA errors. There are also several genetic diseases caused by the inability of cells to fix DNA properly, for instance, and work on the repair methods aids understanding of these ailments and how to treat them.
Scientists used to believe that DNA molecules were extremely stable. After all, they had to reliably transmit genetic information from generation down to generation. Then in the 1970s Lindahl demonstrated that the neat double helix and its components constantly decays. Every day, hundreds of those components, the DNA building block chemicals abbreviated as A, T, C, and G, get knocked out of their places. If the process continued unabated, the development of life on Earth would have been impossible. This insight led Lindahl to discover a series of enzymes and reactions, called base excision repair, which constantly works to fight this decay. The C building block, for instance, is repeatedly broken down into another molecule that should not be in DNA. The enzymes Lindahl found identify that broken molecule and rebuild it into a C.

Sancar found that cells use another technique to repair damage to DNA caused by ultraviolet light, the same thing that gives you a sunburn. This DNA fix is called nucleotide excision repair. People born with defects in this repair system will develop skin cancer if they are exposed to sunlight. Excision enzymes cut out the DNA lesions. The cell also uses this repair system to correct DNA damage people get after they are born, when they encounter mutagenic substances.

Finally, Modrich found out how a cell corrects errors that occur during a vital biological process: Cell division, when DNA is replicated. This copying process is supposed to produce identical strands of DNA but often there are stretches of the new stand that do not match up. The set of cellular chemicals that Modrich found, a complex called mismatch repair, scans the strands and fixes them, reducing the error frequency during replication by about a thousand times during each replication cycle.

Without all of these repair mechanisms, we would not be long-lived.

This year’s prize is about the cell’s toolbox for repairing DNA.

Comment by Dr. Krishna Kumari Challa on October 7, 2015 at 6:05am

Comment by Dr. Krishna Kumari Challa on October 6, 2015 at 7:54am

Malaria in pregnancy linked to brain damage in babies
Babies whose mothers contract malaria during pregnancy could suffer later problems, including depression and learning difficulties, according to a study done in mice.

The study found that unborn babies whose mothers were infected with malaria had lower levels of the substances needed for normal brain development and function. It was published in the journal PLOS Pathogens last week (24 September). This still has to be confirmed in human beings.

These neurocognitive impairments were associated with decreased tissue levels of neurotransmitters in regions of the brain linked to the observed deficits. Disruption of maternal C5a complement receptor signaling restored the levels of neurotransmitters and rescued the associated cognitive phenotype observed in malaria-exposed offspring.
The reduction was thought to be caused by excess activation of an immune response in the mother that is used to tackle malaria, but that also appears to interfere with the production of these substances, the researchers say.

As a result of their mothers’ malaria infection, the mice developed symptoms of depression and cognitive impairment after birth, such as memory problems and reduced social interaction, the study says.
The research was carried out to investigate how malaria might affect unborn children. This is particularly important as pregnant women have a higher risk than other women of being infected with the malaria parasite Plasmodium falciparum and of developing a severe form of the infection. This is because pregnancy reduces their immunity to malaria.
The research team also tried to stop malaria from harming unborn baby mice by blocking the immune response that had become excessively activated. This restored the key brain substances to their normal levels, so the baby mice no longer developed symptoms of depression and mental impairments after birth.

This treatment would be too expensive to roll out on a large scale in humans.
http://journals.plos.org/plospathogens/article?id=10.1371/journal.p...

Comment by Dr. Krishna Kumari Challa on October 6, 2015 at 5:30am

Medicine Nobel 2015 prizes were given to William Campbell (Ireland), Satoshi Omura (Japan) and  Youyou Tu (China) for their discoveries of treatments against parasites.

In the 2015 Nobel Prize for Physiology or Medicine was given to Youyou Tu, who consulted traditional texts on herbs to help isolate and purify the malaria drug artemisinin. The medication saves some 100,000 lives each year in Africa as well as restoring the health of countless others around the world. The other half of the Nobel prize was awarded to William C. Campbell and Satoshi Omura for their discovery of Avermectin, whose many derivatives were first used as veterinary treatments before being developed into a drug that has stopped the spread of river blindness in many parts of western Africa.

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Discoverers of Shape-Shifting Particles Win the Nobel Physics Prize

Takaaki Kajita and Arthur B. McDonald share the 2015 award for the discovery that neutrino particles can change “flavor”—and, unexpectedly, have mass.

Finding some of nature’s weirdest particles has won two experimenters the 2015 Nobel Prize in Physics. Japanese scientist Takaaki Kajita and Canadian researcher Arthur B. McDonald will share this year’s award for the discovery that neutrinos—fundamental particles that come in three types, or flavors—can actually swap identities and change flavors as they fly through space. Their turn-of-the-millennium discovery not only revealed the strangeness of these shape-shifting particles—it also contradicted the Standard Model of particle physics. At the time, physicists predicted that neutrinos would weigh nothing at all. For neutrinos to change flavors, however, they must have mass. Kajita and McDonald demonstrated that neutrinos must therefore have a very small but nonzero mass. Exactly how much mass each neutrino flavor has remains one of the most important unanswered questions in physics today.

They won the prize for the discovery of neutrino oscillations, which shows that neutrinos have mass. here are three kinds of neutrinos. Electron-neutrinos, mu-neutrinos and tau-neutrinos. This year’s prize is awarded to the experimental discovery that neutrinos can change identity. For example, a mu-neutrino can become a tau-neutrino and vice versa. They oscillate.

Comment by Dr. Krishna Kumari Challa on October 4, 2015 at 11:06am

A diet high in processed fructose sabotages rats’ brains’ ability to heal after head trauma, UCLA neuroscientists report. Revealing a link between nutrition and brain health, the finding offers implications for the 5.3 million Americans living with a traumatic brain injury, or TBI.
Americans consume most of their fructose from processed foods sweetened with high-fructose corn syrup. The researchers found that processed fructose inflicts surprisingly harmful effects on the brain’s ability to repair itself after a head trauma.

Fructose also occurs naturally in fruit, which contains antioxidants, fiber and other nutrients that prevent the same damage.
The UCLA team found that fructose altered a wealth of biological processes in the animals’ brains after trauma. The sweetener interfered with the ability of neurons to communicate with each other, rewire connections after injury, record memories and produce enough energy to fuel basic functions. The findings suggest that fructose disrupts plasticity — the creation of fresh pathways between brain cells that occurs when we learn or experience something new.
Earlier research has revealed how fructose harms the body through its role in contributing to cancer, diabetes, obesity and fatty liver.
Sources of fructose in the western diet include honey, cane sugar (sucrose) and high-fructose corn syrup, an inexpensive liquid sweetener. Made from cornstarch, the liquid syrup is widely added as a sweetener and preservative to processed foods, including soft drinks, condiments, applesauce and baby food.
source: University of California Los Angeles

In the UCLA study, is published on 2nd Oct., 2015, in the Journal of Cerebral Blood Flow and Metabolism.

Comment by Dr. Krishna Kumari Challa on October 4, 2015 at 11:00am

Jennifer Doudna, who invented a gene-editing tool that has taken the research world by storm, was named one of five laureates of the 2016 L’Oréal-UNESCO for Women in Science Awards in the field of life sciences.
The awards, given annually to one female scientist from each of five continents, were announced Oct. 2 in Paris by the L’Oréal Foundation and the United Nations Educational Scientific and Cultural Organization, which partner on the award.
Doudna and the other laureates will be honored at a ceremony on March 24, 2016, at the Sorbonne University’s Grand Amphitheatre in Paris. Each laureate will receive €100,000.

Doudna, the laureate from North America, is joined by European laureate Emmanuelle Charpentier. Doudna and Charpentier together discovered a unique technique used by bacteria to cut and kill viral DNA, and reengineered this system to cut any type of DNA, including human. First reported in 2012, the technology is being used worldwide to create potential genetic therapies for inherited disease, and in basic research to discover the causes of disease.
In the 18 years since the L’Oréal-UNESCO For Women in Science Awards were founded, 92 women have been recognized and two have gone on to win Nobel Prizes, including Blackburn, who won the Nobel Prize in Physiology or Medicine in 2009 for work conducted at UC Berkeley.
http://news.berkeley.edu/2015/10/02/doudna-receives-women-in-scienc...

Comment by Dr. Krishna Kumari Challa on October 3, 2015 at 7:18am

Good News: India Pledges to Curb Greenhouse Gas Growth
India has pledged to slash its emissions intensity relative to economic growth and make a massive push on clean energy by 2030 as part of its formal submission to the United Nations ahead of landmark global warming negotiations in Paris.

India’s vow to unconditionally cut emissions intensity 33 to 35 percent below 2005 levels and boost the share of non-fossil-fuel energy sources more than threefold as long as it receives assistance from Western countries was widely praised by the environmental community.

Comment by Dr. Krishna Kumari Challa on October 3, 2015 at 6:57am

Children who acquire four kinds of gut bacteria in the first three months of their lives can be protected from developing asthma, according to new research.

The four bacteria, called FLVR (Faecalibacterium, Lachnospira, Veillonella, and Rothia), are naturally acquired by most babies through exposure in their home surroundings. However, some infants miss out, and it’s those children who are at most risk of developing asthma, according to researchers from the University of British Columbia in Canada.
This research supports the hygiene hypothesis that we’re making our environment too clean. It shows that gut bacteria play a role in asthma, but it is early in life when the baby’s immune system is being established.
The researchers looked at faecal samples from 319 children who took part in the Canadian Healthy Infant Longitudinal Development Study. The samples revealed that the three-month-old infants at high risk of developing asthma – determined by allergy tests to see if the children demonstrated wheezing – had lower amounts of FLVR bacteria than the kids who didn’t show such signs of developing the disease.

The researchers also found that by one year of age, the differences in gut bacteria between the high-risk and low-risk children had significantly lessened, suggesting that early exposure to FLVR bacteria in those first three months of life could be crucial in warding off asthma later on. The study emphasises that in that first 100 days the structure of the gut microbiome seems to be very important in influencing the immune responses that cause or protect us from asthma.
" Early infancy microbial and metabolic alterations affect risk of childhood asthma"
http://stm.sciencemag.org/content/7/307/307ra152

http://allergen-nce.ca/research/strategy/child/

Comment by Dr. Krishna Kumari Challa on October 2, 2015 at 10:04am

Comment by Dr. Krishna Kumari Challa on October 2, 2015 at 6:08am

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