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Comment by Dr. Krishna Kumari Challa on December 18, 2017 at 11:43am

A new wave of thought to fight super bugs

Comment by Dr. Krishna Kumari Challa on December 7, 2017 at 10:52am

http://hyper.ahajournals.org/content/70/3/479.full
Report of the National Heart, Lung, and Blood Institute Working Group on the Role of Microbiota in Blood Pressure Regulation

Comment by Dr. Krishna Kumari Challa on December 5, 2017 at 8:11am

Antibiotic weakness: When the medicines you take themselves help microbes survive?

A new study has found that medications can change body chemistry to make it more hospitable to invading microbes! 

Antibiotics save lives, but they are not fail-safe. Even when microbes haven’t acquired drug-evading genetic mutations—a hallmark of antibiotic resistance—the medications don’t always clear infections. A new study identifies a surprising reason why: At infection sites, antibiotics change the natural mixture of chemicals made by the body in ways that protect infecting bacteria. They also thwart the ability of the host’s immune cells to fight off the intruders.

These chemical changes were incited not by bacterial cells, but by the animals’ own cells. The researchers learned this after giving antibiotics to so-called “germ-free” mice that had no bacteria and saw the same chemical changes. 

Scientists are not sure how the chemicals elicit these effects. But they note some of the compounds slow down aspects of bacterial metabolism, making the antibiotics less lethal. Most antibiotics speed up bacterial metabolism while also de-stabilizing the metabolic process, leading to the build-up of toxic molecules inside the bacteria that help to kill them. With this process dampened, bacteria more easily survive.

The findings do suggest infections are complicated environments, and that antibiotics influence more than just bacterial cells, often in unexpected ways. And it is important to understand these complications for effective treatments.

These findings, published recently in Cell Host & Microbe, could help scientists “build more effective treatments''.

http://www.cell.com/cell-host-microbe/fulltext/S1931-3128(17)30455-9

Comment by Dr. Krishna Kumari Challa on December 5, 2017 at 6:59am

The existence of Yeti as described in the folklore and mythology in the Tibetan Plateau–Himalaya region has been shrouded in mystery. According to the stories in the Himalayan region, Yeti, or the Abominable Snowman is an ape-like creature taller than a human being.

Though previous attempts in the biological identification of Yeti were not successful, a recent research report published in the Proceedings of the Royal Society B suggests that Yeti is a bear. A multinational team of investigators led by Dr. Charlotte Lindqvist of the University of Buffalo at New York, report on new analyses of 24 field-collected and museum specimens, including hair, bone, skin and fecal samples, collected from bears or purported yetis in the Tibetan Plateau–Himalaya region. Of the nine samples of ostensibly "yeti" origin, eight turned out to be from bears native to the area.

The investigators used a set of genetic elements called mitochondria to characterize the genetic identify of the animal. The bulk of the genetic information in a cell is stored in the DNA which is contained in the nucleus. All nucleated cells also have a small circular DNA outside of the nucleus, within another cytoplasmic organelle called mitochondria. These DNA copies are therefore called mitochondrial DNA or mtDNA. As these mtDNAs are outside of the nucleus, only the maternal mtDNAs will be transferred to the offsprings. Therefore, mtDNA serves as a marker of ancestry.

Based on both amplified mtDNA loci as well as complete mitogenomes, they reconstructed maternal phylogenies to increase knowledge about the phylogenetic relationships and evolutionary history of Himalayan and Tibetan bears. The scientists were able to determine the clade affinities of all the purported yeti samples in this study and inferred their well-supported and resolved phylogenetic relationships among extant bears in the Tibetan Plateau and surrounding Himalayan Mountains.

Tianying Lan, Stephanie Gill, Eva Bellemain, Richard Bischof, Muhammad Ali Nawaz, Charlotte LindqvistEvolutionary history of enigmatic bears in the Tibetan Plateau–Himalaya region and the identity of the yeti. Proceedings of the Royal Society B Published 29 November 2017.DOI: 10.1098/rspb.2017.1804 

Comment by Dr. Krishna Kumari Challa on November 23, 2017 at 8:28am

New solution to antibiotic resistance

One of the ways antibiotic resistance genes spread in hospitals and in the environment is that the genes are coded on plasmids that transfer between bacteria. A plasmid is a DNA fragment found in bacteria or yeasts. It carries genes useful for bacteria, especially when these genes encode proteins that can make bacteria resistant to antibiotics.Now a team of scientists at UdeM's Department of Biochemistry and Molecular Medicine has come up with a novel approach to block the transfer of resistance genes. The study by Bastien Casu, Tarun Arya, Benoit Bessette and Christian Baron was published in early November in Scientific Reports.

The researchers screened a library of small chemical molecules for those that bind to the TraE protein, an essential component of the plasmid transfer machinery. Analysis by X-ray crystallography revealed the exact binding site of these molecules on TraE. Having precise information on the binding site enabled the researchers to design more potent binding molecules that, in the end, reduced the transfer of antibiotic-resistant, gene-carrying plasmids.

Building on their encouraging new data, Baron and his colleagues are now working with the medicinal chemists at UdeM's IRIC (Institut de recherche en immunologie et cancérologie) to develop the new molecules into powerful inhibitors of antibiotic resistance gene transfer. Such molecules could one day be applied in clinics in hospitals that are hotbeds of resistance, the researchers hope.

Ultimately, reducing the transfer of antibiotic-resistance plasmids could help preserve the potency of antibiotics, contributing to an overall strategy to help improve human health

Comment by Dr. Krishna Kumari Challa on November 16, 2017 at 6:35am

Pollution might increase lightening strikes

Scientists have already linked aerosol emissions to increases in lightning over areas of the Amazon prone to forest fires (pdf) as well as regions of China with thick air pollution. The clearest example yet of humanity’s influence on atmospheric electrostatic discharges, however, surfaced recently when researchers discovered dense trails of lightning in the soot-filled skies over two of the world’s busiest shipping routes in the Indian Ocean and South China Sea.

Poring over 12 years of detailed data, atmospheric scientists Joel Thornton  at the University of Washington, postdoc Katrina Virts of NASA Marshall Space Flight Center and their colleagues found lightning flashes occur nearly twice as often directly above heavily trafficked shipping lanes as they do elsewhere over the ocean. The increased frequency of lightning follows the exhaust from ships and cannot be explained by meteorological factors such as winds or the atmosphere’s temperature structure, according to a study, published in Geophysical Research Letters in September.

The team noticed a greater density of lightning in locations where ships blast emissions, including sulfur and nitrogen oxides, into the air. Then the researchers tracked instances of lightning using the World Wide Lightning Location Network (WWLLN)—a system of acoustic sensors that detect electrical disturbances all around the globe.

Lightning is a natural feature of storms that occurs when certain conditions are met. Particles in a cloud rub together, gathering opposite charges that eventually separate into positive and negative regions. These two poles create a space across which a transfer of charge—or lightning bolt—may then occur. Sometimes the bolts transmit the charge to the ground and lightning strikes.

But we are now learning the amount of lightning generated may be influenced by factors that go beyond natural meteorology, including aerosols. Other recent studies have given credence to the idea aerosols are linked to more lightning. 

Comment by Dr. Krishna Kumari Challa on November 15, 2017 at 8:41am

Comment by Dr. Krishna Kumari Challa on November 14, 2017 at 9:47am

More than 15,000 scientists from 184 countries issue 'warning to humanity'

More than 15,000 scientists around the world have issued a global warning: there needs to be change in order to save Earth.

It comes 25 years after the first notice in 1992 when a mere 1,500 scientists issued a similar warning. 

This new cautioning — which gained popularity on Twitter with #ScientistsWarningToHumanity — garnered more than 15,000 signatures. 

What is it about? Read the article here:

http://scientistswarning.forestry.oregonstate.edu/sites/sw/files/Wa...

--

A team of researchers in Singapore has identified a molecular pathway that suppresses virus-induced cancers. They published their findings in PLOS Pathogens. Some cancers are known to be caused by viral infections. For example, two strains of the human papillomavirus (HPV) are responsible for up to 70 percent of cervical cancer cases. The virus causes abnormal cell growth by inserting its genetic material into the cells of the cervix. Uncontrolled cell growth is typically prevented by the shortening of telomeres—protective caps on the ends of chromosomes. Each time a cell divides into two, the telomeres get shortened, and the cell eventually stops dividing. Cancer cells, however, are known to bypass this limit by producing telomerase, an enzyme that extends the length of telomeres. In HPV-infected cells, the protein TIP60 is known to prevent progression to cervical cancer, but the interactions between TIP60 and telomerase remain unknown. In this study, researchers at the Cancer Science Institute of Singapore (CSI Singapore) and the National University of Singapore (NUS) examined the regulation of telomerase by TIP60 in virus-induced cancer cells. The team discovered that TIP60 inhibits telomerase by interacting with and modifying a partner molecule, Sp1. When TIP60 modifies Sp1, Sp1 can no longer bind to the regulatory sequences of the telomerase gene to activate it. This results in less production of telomerase, which prevents the cancer cells from continuous division. The identification of this molecular pathway opens a new window of hope for therapeutic interventions against cancers. “Our findings hold exciting potential in the fight against a range of virus-induced cancers, including cervical cancer, liver cancer and Burkitt’s Lymphoma,” said study corresponding author Dr. Sudhakar Jha, a principal investigator at CSI Singapore. “Given that 85 percent of cancers are triggered by high amounts of telomerase, our study, which lends a deeper insight into the inhibition of telomerase by TIP60, could also be applied to other groups of cancer such as breast, colorectal and ovarian cancer. Our next step is therefore to investigate the influence of this new pathway in these other groups of cancer,” he added. The article can be found at: Rajagopalan et al. (2017) TIP60 Represses Telomerase Expression by Inhibiting Sp1 Binding to the TERT Promoter.

Comment by Dr. Krishna Kumari Challa on November 11, 2017 at 8:48am

How science is saving lives....

A team of researchers from Germany, Austria, and Italy gave a young boy with the genetic disease junctional epidermolysis bullosa (JEB) new skin cells that saved his life. The work is detailed in the Nature paper "Regeneration of the entire human epidermis using transgenic stem ce..."

JEB is caused by genetic mutations in the genes LAMA3, LAMB3 or LAMC2. These three genes are required to form the protein laminin - a key component of the extracellular matrix which acts like the glue that holds cells together. When one of these genes is mutated, the extracellular matrix is disrupted and the skin blisters, erodes, and has recurrent infections. This disease is a nightmare - resulting in pain while living and an early death.  

Altering a gene (in this case, making a correction) is done in labs all around the world every day. This team of scientists had talent to do this. They worked with a genetic disease with known mutations in cells that could be modified in cells that could then grafted back onto the patient.

The first step in the process was the correction of the genetic mutation.

This is potentially the least complicated step in this process. The scientists had all of the information and tools necessary to make this happen. The DNA was constructed and put into a virus that infects skin cells. This viral vector is an incredibly useful way to place DNA into cells. The new DNA then becomes part of the genome of the skin cell. In this process, the skin cell now has a corrected version of the mutated gene in their genome. 

The second step of the process was making more of the corrected cells. In this particular part of the process - as our skin is one of the few organs that have stem cells positioned in and amongst our normal skin cells (called keratinocytes)- these are not the frequently discussed pluripotent stem cells; instead, these stem cells are dedicated to making more skin. This is important for the normal wear and tear that happens to our skin. When the mutated gene was corrected in one of these cells, it would make more cells with the corrected gene. Over time, there were enough cells to graft onto the patient. 

Both of these two major steps are events that happen in labs across the world every day. But, like many significant advancements, this was made possible by a combination of the right problem, the right tools and good hands of motivated scientists. So, some good old fashioned genetic sequencing and cell culture have saved a boys life - and that is the most amazing scientific story of the year.  

Comment by Dr. Krishna Kumari Challa on November 10, 2017 at 8:31am

Nov. 10th: World Science Day for Peace and Development
An internationally celebrated day to highlight the importance of science in and for society and that science, peace and development are interlinked

Celebrated every 10 November, World Science Day for Peace and Development highlights the important role of science in society and the need to engage the wider public in debates on emerging scientific issues. It also underlines the importance and relevance of science in our daily lives.

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