Some Science

Comment

Comment by Dr. Krishna Kumari Challa 4 hours ago

Swimmers have to be careful about not only the infections they get from bacteria and virus but also harm caused by brain eating amoeba  Naegleria fowleri that dwells in dwells in warm freshwater lakes and rivers and usually targets children and young adults. Once in the brain it causes a swelling called primary meningoencephalitis. The infection is almost universally fatal.

The amoeba has strategies to evade the immune system, and treatment options are meager partly because of how fast the infection progresses.

But research suggests that the infection can be stopped if it is caught soon enough. So what happens during an N. fowleri infection?

The microscopic amoebae, which can be suspended in water or nestled in soil, enter the body when water goes up the nose. After attaching to the mucous membranes in the nasal cavity, N. fowleri burrows into the olfactory nerve, the structure that enables our sense of smell and leads directly to the brain. It probably takes more than a drop of liquid to trigger a Naegleria infection; infections usually occur in people who have been engaging in water sports or other activities that may forcefully suffuse the nose with lots of water—diving, waterskiing, wakeboarding, and in one case a baptism dunking.

It turns out that "brain eating" is actually a pretty accurate description for what the amoeba does. After reaching the olfactory bulbs, N. fowleri feasts on the tissue there using suction-cup-like structures on its surface. This destruction leads to the first symptoms—loss of smell and taste—about five days after the infection sets in.

From there the organisms move to the rest of the brain, first gobbling up the protective covering that surrounds the central nervous system. When the body notices that something is wrong, it sends immune cells to combat the infection, causing the surrounding area to become inflamed. It is this inflammation, rather than the loss of brain tissue, that contributes most to the early symptoms of headache, nausea, vomiting and stiff neck. Neck stiffness in particular is attributable to the inflammation, as the swelling around the spinal cord makes it impossible to flex the muscles.

As N. fowleri consumes more tissue and penetrates deeper into the brain, the secondary symptoms set in. They include delirium, hallucinations, confusion and seizures. The frontal lobes of the brain, which are associated with planning and emotional control, tend to be affected most because of the path the olfactory nerve takes. But after that there’s kind of no rhyme or reason—all of the brain can be affected as the infection progresses.

Ultimately what causes death is not the loss of grey matter but the extreme pressure in the skull from the inflammation and swelling related to the body’s fight against the infection. Increasing pressure forces the brain down into where the brain stem meets the spinal cord, eventually severing the connection between the two. Most patients die from the resulting respiratory failure less than two weeks after symptoms begin.

- SA

Comment by Dr. Krishna Kumari Challa yesterday

Carbs and gut microbes fuel colon cancer
Sugar-loving bacteria support the emergence of tumors in mice
http://www.cell.com/cell/abstract/S0092-8674%2814%2900736-3

Gut Microbial Metabolism Drives Transformation of Msh2-Deficient Colon Epithelial Cells
The etiology of colorectal cancer (CRC) has been linked to deficiencies in mismatch repair and adenomatous polyposis coli (APC) proteins, diet, inflammatory processes, and gut microbiota. However, the mechanism through which the microbiota synergizes with these etiologic factors to promote CRC is not clear. We report that altering the microbiota composition reduces CRC in APCMin/+MSH2−/− mice, and that a diet reduced in carbohydrates phenocopies this effect. Gut microbes did not induce CRC in these mice through an inflammatory response or the production of DNA mutagens but rather by providing carbohydrate-derived metabolites such as butyrate that fuel hyperproliferation of MSH2−/− colon epithelial cells. Further, we provide evidence that the mismatch repair pathway has a role in regulating β-catenin activity and modulating the differentiation of transit-amplifying cells in the colon. These data thereby provide an explanation for the interaction between microbiota, diet, and mismatch repair deficiency in CRC induction.

•Gut microbiota induce colon cancer in genetically sensitized MSH2-deficient mice
•Reduced dietary carbohydrates decreased polyp frequency in APCMin/+MSH2−/− mice
•The carbohydrate metabolite butyrate induces colon cancer in APCMin/+MSH2−/− mice
•MSH2 regulates β-catenin activity and/or transit-amplifying cell differentiation

Comment by Dr. Krishna Kumari Challa yesterday

Not enough funding for basic science in India: Kalam (Scientist and former President of India)
He called for 'big' investment to promote researches in higher education
Former President A P J Abdul Kalam today said there is not enough funding for basic science in India and called for 'big' investment to promote researches in higher education.

"There is not enough funding for basic sciences in India. We have to invest in a big way and I am pushing that idea," Kalam told PTI on the sidelines of a lecture at the IIM-Shillong here.
- PTI

Comment by Dr. Krishna Kumari Challa yesterday

Parts of the primordial soup in which life arose have been maintained in our cells today according to scientists at the University of East Anglia. Research published today in the Journal of Biological Chemistry reveals how cells in plants, yeast and very likely also in animals still perform ancient reactions thought to have been responsible for the origin of life -- some four billion years ago.
The new research shows how small pockets of a cell -- known as mitochondria -- continue to perform similar reactions in our bodies today. These reactions involve iron, sulfur and electro-chemistry and are still important for functions such as respiration in animals and photosynthesis in plants.
For example small pockets of a cell called mitochondria deal with electrochemistry and also with toxic sulfur metabolism. These are very ancient reactions thought to have been important for the origin of life.

The new research has shown that a toxic sulfur compound is being exported by a mitochondrial transport protein to other parts of the cell. We need sulfur for making iron-sulfur catalysts, again a very ancient chemical process.

The work shows that parts of the primordial soup in which life arose has been maintained in our cells today, and is in fact harnessed to maintain important biological reactions.
The research was carried out at UEA and JIC in collaboration with Dr Hendrik van Veen at the University of Cambridge.
Source: http://www.uea.ac.uk/mac/comm/media/press/2014/July/primordial-soup

Comment by Dr. Krishna Kumari Challa on Wednesday

Cheap Nasal Spray May Save Snakebite Victims
A novel, nasal spray-based approach may help reduce the toll, according to researchers.
A team of researchers, led by Matthew Lewin, from the California Academy of Sciences, United States, and Stephen Samuel, from Trinity College Dublin in Ireland, says a simple nasal spray containing a substance called neostigmine can reduce snakebite fatalities.

“It would be one ingredient primarily directed against rapid onset paralysis—one of the causes of fast death following snakebite,” Lewin tells SciDev.Net. “It is inexpensive and available everywhere in the world.”

If combined with atropine, a substance that is absorbed through the nose, neostigmine would have few ill effects, according to Lewin.

The team tested the nasal spray on mice injected with fatal doses of venom from the Indian cobra. Mice treated with the spray outlived those that were not given it and, in many cases, survived, according to a study they published in the Journal of Tropical Medicine.
The nasally administrated drug is an alternative to antivenoms, Lewin says. He argues that, besides being expensive, antivenoms can vary in effectiveness depending on factors including the snake’s diet, the time of year and the geographic location.

Furthermore, a paper published in the Proceedings of the National Academy of Sciences last month reports that it may be harder than originally thought to develop an antivenom that works against many snakebites.

“We discovered that the genetics of the animals can be very similar, yet their venoms very different,” the lead author, Nicholas Casewell, from Liverpool School of Tropical Medicine, United Kingdom.
Using six related snakes—the Saharan horned viper, the puff adder and four species of saw-scaled vipers—Casewell and colleagues discovered that various genetic regulatory processes act at different stages of toxin production.

These processes result in major differences in toxin composition, and these different toxins cause different pathologies or levels of toxicity when they are injected, and they also undermine antivenom treatment.
There are about 500 species of dangerous, venomous snakes worldwide.
Antivenom is necessary, but not sufficient to manage this problem. Its limitations are fairly well known at this point and we need a better bridge to survival.

The nasal spray could be a cheap, fast and easy method to treat the paralysis caused by snakebites.
In 2013, to see if neostigmine could be absorbed through the human nose, Lewin tried the spray on himself, after being infused with a drug to induce awake paralysis in a manner similar to cobra venom. He made a completely recovery in a little over two hours, as described in Clinical Case Reports. Clinical trials of the spray are now planned in India.
http://www.hindawi.com/journals/jtm/2014/131835/

Comment by Dr. Krishna Kumari Challa on Wednesday

Cancer treatment clears two Australian patients of HIV

Patients' virus levels became undetectable after bone-marrow therapy with stem cells.
http://www.nature.com/news/cancer-treatment-clears-two-australian-p...

Comment by Dr. Krishna Kumari Challa on Tuesday

Kidney Stone Risk Creeps North as Climate Changes
A link between heat and the painful stones
As ambient temperatures increase, your fluid losses through skin increase. With more water coming out as sweat and less coming out as urine, minerals can build up and form stones. In cold weather, researchers suspect, people dehydrate in warm, dry indoor air.

And you might have this effect without even realizing the fluid loss through your skin is increasing.

Not realizing you're dehydrated is a big part of the problem. In drier climates, people may not have puddles of sweat to gauge how much water they're losing. This is especially important when people migrate to warmer areas and aren't used to drinking more water.
- http://www.eenews.net/

Comment by Dr. Krishna Kumari Challa on Tuesday

Myopia and Level of Education
Main Outcome Measures

Prevalence and magnitude of myopia in association with years spent in school and level of post-school professional education.
Results

Individuals who graduated from school after 13 years were more myopic (median, −0.5 diopters [D]; first quartile [Q1]/third quartile [Q3], −2.1/0.3 D) than those who graduated after 10 years (median, −0.2 D; Q1/Q3, −1.3/0.8 D), than those who graduated after 9 years (median, 0.3 D; Q1/Q3, −0.6/1.4 D), and than those who never finished secondary school (median, 0.2 D; Q1/Q3, −0.5/1.8 D; P<0.001, respectively). The same holds true for persons with a university degree (median, −0.6 D; Q1/Q3, −2.3/0.3 D) versus those who finished secondary vocational school (median, 0 D; Q1/Q3, −1.1/0.8 D) or primary vocational school (median, 0 D; Q1/Q3, −0.9/1.1 D) versus persons without any post-school professional qualification (median, 0.6 D; Q1/Q3, −0.4/1.7 D; P<0.001, respectively). Of persons who graduated from school after 13 years, 50.9% were myopic (SE, ≤−0.5 D) versus 41.6%, 27.1%, and 26.9% after 10 years, in those who graduated after 9 years, and in those who never graduated from secondary school, respectively (P<0.001). In university graduates, the proportion of myopic persons was higher (53%) than that of those who graduated from secondary (34.8%) or primary (34.7%) vocational schools and than in those without any professional training (23.9%; P<0.001, respectively). In multivariate analyses: higher school and professional levels of education were associated with a more myopic SE independent of gender. There was a small effect of age and SNPs. Conclusions Higher levels of school and post-school professional education are associated with a more myopic refraction. Participants with higher educational achievements more often were myopic than individuals with less education. http://www.aaojournal.org/article/S0161-6420%2814%2900364-9/abstract

Comment by Dr. Krishna Kumari Challa on Monday

Comment by Dr. Krishna Kumari Challa on July 20, 2014 at 8:35am

How media people are twisting and spinning things to mislead people to make them believe in what they beleive:
''Aliens on the Moon' TV Show Adds Weird UFO Twists to Apollo Tales''
What one person sees as a overly magnified image with distortions that merely form strange patterns, another person sees as incontrovertible proof that extraterrestrials have left giant antennas, spaceships and industrial complexes on the moon.
The footage was later proven to be fake.
The Story Behind the 'Alien Autopsy' Hoax
The film—purporting to depict the post mortem of an extraterrestrial who died in a UFO crash at Roswell, New Mexico, in 1947—was part of a "documentary" that aired on the Fox television network.
http://www.livescience.com/742-story-alien-autopsy-hoax.html
The heart of "Aliens on the Moon" is a review of decades-old photographs from the Apollo missions, with commentary by sources ranging from former Apollo astronauts Buzz Aldrin and Edgar Mitchell to old standbys on the UFO scene (MUFON analyst Marc D'Antonio, "Dark Mission" co-author Mike Bara and physicist John Brandenburg, plus photo lab workers Donna Hare and Ken Johnston).
many of the show's seemingly baffling mysteries can be resolved much more easily, by looking at higher-resolution imagery from NASA's Lunar Reconnaissance Orbiter. For example, straight-line tracks that UFO fans might interpret as evidence of massive machines on the moon are more clearly seen as the result of rolling boulders.
http://www.nbcnews.com/science/space/aliens-moon-tv-show-adds-weird...

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