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Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 8:20am

A parasite's cancerous cells can give human beings cancer! Yes, true. This really has happened!
In a rare case, a patient’s weakened immune system may have let tapeworm spread disease
A 41-year-old man in Medellín, Columbia, went to the doctor complaining of fever, cough, fatigue and weight loss that had lasted several months. He had been already infected with AIDS and had a very weak immune system by then. Scans revealed tumors in his lungs, liver, adrenal glands, lymph nodes and other spots in his body. The disease looked like cancer, but it puzzled doctors: the small cells in the growths weren’t human cancer cells. They were much smaller!

DNA analysis revealed a shock: The cancer cells came from dwarf tapeworms (Hymenolepiasis nana), pathologist Atis Muehlenbachs of the U.S. Centers for Disease Control and Prevention and colleagues report in the Nov. 5 New England Journal of Medicine. Contagious cancers affect dogs, Tasmanian devils and clams, but this is the first time researchers have found a parasite living in him giving a person cancer.

HIV infection had weakened the man’s immune system so that tapeworm stem cells could grow unchecked, the researchers speculate. Mutations then turned the stem cells into cancer. The case raises concerns that people with weakened immune systems may be in danger of contracting similar tapeworm cancers. “This is a rare disease,” Muehlenbachs says, but “we don’t know how rare.”

Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 7:27am

Scientists tinker with evolution to save Hawaii coral reefs
Hawaii researchers accelerate evolution in attempt to save Hawaii's coral reefs
Scientists at a research center on Hawaii's Coconut Island have embarked on an experiment to grow "super coral" that they hope can withstand the hotter and more acidic oceans that are expected with global warming.
When coral is stressed by changing environmental conditions, it expels the symbiotic algae that live within it and the animal turns white or bright yellow, a process called bleaching.
If the organisms are unable to recover from these bleaching events, especially when they recur over several consecutive years, the coral will die.
The researchers are taking the coral to their center on the 29-acre isle, once a retreat for the rich and famous and home to television's Gilligan's Island, and slowly exposing them to slightly more stressful water.

They bathe chunks of coral that they've already identified as having strong genes in water that mimics the warmer and more acidic oceans. They are also taking resilient strains and breeding them with one another, helping perpetuate those stronger traits. They have given them experiences that we think are going to raise their ability to survive stress.

The theory they are testing is called assisted evolution, and while it has been used for thousands of years on other plants and animals, the concept has not been applied to coral living in the wild.
-AP

Comment by Dr. Krishna Kumari Challa on November 6, 2015 at 7:20am

183 scientists sign letter asking BMJ to retract its bogus nutrition investigation

The investigation has 'no place in the pages of a prominent scientific journal'
More than 180 scientists from around the world have signed a letter urging the British Medical Journal to retract its bogus investigation of the 2015 US dietary guidelines report. As The Verge previously reported, the investigation contains multiple misleading statements and factual inaccuracies. But today's letter, which was sent to the BMJ this morning, doesn't mince words. It outlines the many problems with the article, and states that the investigation is "so riddled with errors" that it has "no place in the pages of a prominent scientific journal."
The US government publishes a revised set of dietary guidelines every five years. These guidelines are very important; they affect how companies label food, what scientists focus on in their research, and what students eat in school. But in September, the BMJ published an investigation that went after the report that informs those guidelines; it was written by Nina Teicholz, author of a book entitled The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet. The article suggested that the committee responsible for the report "abandoned established methods for most of its analyses," overlooking a number of important studies in the process. The article also stated that the committee had "deleted meat" from its list of recommended foods. However, both these statements are untrue.

Unless the BMJ retracts the investigation, many of these errors will likely still be used by the meat industry to suppress the committee's advice on lowering the consumption of red meat.
A number of scientists have told me that it's mind-boggling that the BMJ would publish this article critiquing a report by a panel by well-respected scientists without even asking the panel to respond," says Bonnie Liebman, the director of nutrition at the Center for Science in the Public Interest and the person spearheading the effort to get the journal to retract the investigation. It took the BMJ two days to publish a response from the panel.
In September, a number of news outlets — including Time, Newsweek, and Mother Jones — reported the story without questioning the investigation's faulty reporting. The fact that both the BMJ and Teicholz said that they stood by the article surely did not help.
http://cspinet.org/bmj-retraction-letter.html
http://www.theverge.com/science/2015/11/5/9675598/bmj-183-scientist...

Comment by Dr. Krishna Kumari Challa on November 5, 2015 at 8:25am

Controlling mosquitoes the natural way: Insect-control experts are now hoping that deploying the laboratory mosquitoes will eventually slash the number of wild mosquitoes in people’s neighbourhoods.
A new plan to release thousands of mosquitoes in people's backyards in Los Angeles is underway. The bugs—all males—would not bite humans like females do, and area officials hoped these particular insects would block further reproduction of their kind. To some local residents the approach seemed a bit counterintuitive at first. Yet they were told the method would help curb pesticide use while simultaneously beating back their mosquito population.

The bugs to be released were not genetically modified. But they were not exactly garden-variety mosquitoes, either. The male mosquitoes were raised in a laboratory where they were infected with Wolbachia, a natural bacterium that would effectively sterilize them. When the males are released into people’s backyards and mate with wild females, the resulting eggs—for reasons not yet fully understood—simply will not hatch, leading to fewer mosquitoes.
The biology of how Wolbachia interact with their hosts is a bit complex. If a male mosquito with Wolbachia mates with an uninfected female, then their eggs will not hatch. That is the key to Dobson’s approach. Yet if two mosquitoes that both have Wolbachia mate, then their resulting eggs will hatch as normal, although the offspring will potentially harbor Wolbachia. Basically, their lives will go on as usual and they will be able to reproduce. Similarly, if an infected female mates with an uninfected male, then their resulting eggs will also hatch as normal—although again, the offspring will potentially also be infected.

This is not the first time Wolbachia has been auditioned as a way to hamper the spread of mosquito-borne diseases—scientists have previously used a strain of the bacterium to curb the spread of dengue.
- Scientific American

Comment by Dr. Krishna Kumari Challa on November 5, 2015 at 7:10am

Effects of an AC or DC Currents on the Human Body

The three basic factors that determine what kind of shock you experience are the amplitude of the current, the duration of the current passing through the body, and the frequency.
Direct Currents actually have zero frequency, as the current is constant. However, there are physiological effects during electrocution no matter what type of current.
The factor deciding the effects of the AC and DC current is the path the current takes through the body. If it is from the hand to the foot, it does not pass through the heart, and then the effects are not so lethal.
However DC current will make a single continuous contraction of the muscles compared to AC current, which will make a series of contractions depending on the frequency it is supplied at. In terms of fatalities, both kill but more milliamps are required of DC current than AC current at the same voltage.
If the current takes the path from hand to hand thus passing through the heart it can result in fibrillation of the heart. Fibrillation is a condition when all the heart muscles start moving independently in a disorganized manner rather than in a state of coordination. It affects the ability of the heart to pump blood, resulting in brain damage and eventual cardiac arrest.
Either AC or DC currents can cause fibrillation of the heart at high enough levels. This typically takes place at 30 mA of AC (rms, 60 Hz) or 300 – 500 mA of DC.
Though both AC and DC currents and shock are lethal, more DC current is required to have the same effect as AC current. For example, if you are being electrocuted or shocked 0.5 to 1.5 milliamps of AC 60 Hz current is required and up to 4 mA of DC current is required. For the let-go threshold in AC a current of 3 to 22 mA is required against 15 to 88 of DC current.

Comment by Dr. Krishna Kumari Challa on November 5, 2015 at 7:08am

In direct current electrons flow in one and only one direction (zero frequency). So if you happen to close the circuit by any kind of physical contact forming a low resistance path, the current would start flowing through you. In other words you will be stuck to the conductor as if you just held onto a super.... duper glue. In the meanwhile all your muscles would contract and the heart would stop beating because of the contraction plus there would be other major burns. Eventually you'll die!!
In DC the body just contracts once touched, but in AC the power is made up of frequencies of currents with highs and lows. Thus the body if touched would experience series of contractions depending on the frequency of power. That is like multiple dc shocks in a small gap, and that too the current flows in both directions alternatively. So yes, this kind of shock would totally destroy your muscles. But yeah, if you are lucky enough you can detach yourself from the circuit when the current reaches its 0 and changes direction.

But both AC and DC are lethal.

Comment by Dr. Krishna Kumari Challa on November 5, 2015 at 6:15am

Specialized Cells Help Each Other Survive During Times of Stress
A team led by scientists from the Florida campus of The Scripps Research Institute (TSRI) and the University of Pittsburgh has shown for the first time how one set of specialized cells survives under stress by manipulating the behavior of key immune system cells.

The new study, published recently in the journal Nature Communications, involved mesenchymal stem cells—which live in bone marrow and can differentiate into several different cell types used in bone and connective tissue—and macrophages—immune cells that usually respond to infectious agents or damaged cells by engulfing and devouring them.

“This is the first time anyone has shown how mesenchymal stem cells provide for their own survival by recruiting and then suppressing normal macrophage activity,” said TSRI Professor Donald G. Phinney, who led the study with University of Pittsburgh Associate Professor Luis A. Ortiz. “This finally puts the crosstalk between these cells into the context of cell survival.”

The team’s experiments showed that, like all other cells, mesenchymal stem cells experience stress due to tissue injury and inflammation. When this stress results in damage to the mitochondria (the power houses of the cell), the mesenchymal stem cells recruit the immune system’s macrophages—but in an unusual way.

By reengineering macrophage action with secreted microRNA, the stem cells protect themselves from being targeted and instead package their damaged mitochondria into small sacs known as vesicles and send them out to be engulfed by the macrophage.

Once macrophages subsume the damaged mitochondria, the macrophages are able to repurpose the mitochondria for their own use, replenishing their own energy supplies. Blocking the exchange of damaged mitochondrial to macrophages causes death of the stem cells. Therefore, the process is mutually beneficial.
http://www.nature.com/ncomms/2015/151007/ncomms9472/full/ncomms9472...

Comment by Dr. Krishna Kumari Challa on November 1, 2015 at 12:08pm

Comment by Dr. Krishna Kumari Challa on November 1, 2015 at 11:49am

Comment by Dr. Krishna Kumari Challa on October 31, 2015 at 8:53am

A new study from scientists at The Scripps Research Institute (TSRI) helps explain why cancer metastasis is so hard to stop. The researchers found an additional mechanism explaining how a molecule long linked to cancer progression appears to “seed” the body with metastatic cells long before doctors would typically detect a primary tumor. The molecule, known as epidermal growth factor receptor (EGFR), encourages blood vessel growth early in tumor development—not only feeding the primary tumor, but also providing vehicles for cancer to escape the primary tumor site and travel throughout the body.

“When cancer cells have high levels of EGFR, the tumor has a lot of new, angiogenic blood vessels,” said TSRI Assistant Professor Elena Deryugina, senior author of the new study. “And these vessels are very welcoming for tumor cells and facilitate their dissemination from the very early stages of tumor development.”

The study was published recently in the journal Neoplasia.
When we downregulated EGFR so it wasn’t expressed anymore, the tumor cells were not able to disseminate efficiently,” said TSRI Research Associate Petra Minder, who was first author of the new study. “This gave us a hint that EGFR plays a role in intravasation [an early step of metastatic dissemination during which tumor cells enter angiogenic blood vessels]—we were just not sure how.

The new study shows how EGFR levels make a difference. In experiments using chick embryos, the researchers found that EGFR signaling starts a chain reaction inside tumor cells, ultimately resulting in the release of a molecule called vascular endothelial growth factor (VEGF), known to be active in almost all forms of solid tumors. Released VEGF then binds to endothelial cells, inducing the growth of new blood capillaries and vessels within a developing tumor.

For many years, scientists had seen small blood vessels growing in early-stage tumors, but it was thought these vessels were mostly for supplying tumors with oxygen and nutrients.

“Now we have learned that these newly formed vessels are used by tumor cells for dissemination because of their certain structural properties,” added Deryugina.

The new study shows that these vessels are actually useful for tumors because they are dilated and unusually permeable. Tumor cells can slip into the vessels, escape the primary tumor site and lodge throughout the body. Escaped cells often lie dormant or grow very slowly, not appearing as metastases until after the primary tumor is detected.

The results could also explain why EGFR-inhibiting drugs have had limited success in human patients. While these drugs target EGFR’s effects in primary tumor growth, they don’t address EGFR’s role in blood vessel growth and early metastatic seeding.
The researchers said the findings highlight the urgent need for new methods to diagnose cancers early and new treatments to fight growing metastases.
- http://www.neoplasia.com/article/S1476-5586%2815%2900098-6/abstract

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