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Comment by Dr. Krishna Kumari Challa on April 14, 2015 at 7:17am

Citizen science projects let you make the amazing discoveries
http://www.theweathernetwork.com/news/articles/for-science-citizen-...
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Comment by Dr. Krishna Kumari Challa on April 14, 2015 at 6:49am

Preliminary studies by neuro-scientists tell an interesting story:

Birth control pills taken by women effects brain structure and activity...

 Birth control pills have structural effects on regions of the brain that govern higher-order cognitive activities, suggesting that a woman on birth control pills may literally not be herself -- or is herself, on steroids.

Neuroscientists from the University of California, Los Angeles in the US took brain scans of 90 women who were either currently using the pill or not, and found that two key brain regions were thinner in pill users - the lateral orbitofrontal cortex and the posterior cingulate cortex.

New research suggests that the synthetic steroids delivered by the female contraceptive pill can shrink certain regions of the female brain and could also be altering their function.

Neuroscientists from the University of California, Los Angeles in the US took brain scans of 90 women who were either currently using the pill or not, and found that two key brain regions were thinner in pill users - the lateral orbitofrontal cortex and the posterior cingulate cortex.

These two regions are involved in emotion regulation, decision-making and reward response, and the researchers believe that their findings could help explain why some women become anxious or depressed when taking the contraceptive pill. It's possible that this change in the lateral orbitofrontal cortex may be related to the emotional changes that some women experience when using birth control pills.

Scientists have previously shown that the pill can affect to whom a woman is attracted, and can halve the size of their ovaries. And in 2010, a team from Austria also found that the contraceptive pill could change the shape of the brain regions associated with learning, memory and emotion regulation. But their research suggested that it thickened those regions, rather than thinning them, a result that this new study contradicts.

However, it's important to note that the research is in the very early stages, and didn't look into whether going on or off the pill changed brain shape within the same women. The researchers also haven't studied whether the effects are permanent or temporary.

:"Oral contraceptive pill use is associated with localized decreases in cortical thickness":

http://onlinelibrary.wiley.com/doi/10.1002/hbm.22797/abstract?campa...

Comment by Dr. Krishna Kumari Challa on April 11, 2015 at 9:31am

Why do people do what they do? It is the brain chemistry that decides!
The function of two chemical signals critical to human behavior: Dopamine–responsible for reward and risk-taking–and CREB–needed for learning.
We can now predict future animal behaviors based on past sensory experience, independent of the influence of genetic factors using this information.
Dumping dopamine onto a brain–human or otherwise–makes one more willing to take risks.
Stimulated by large varieties in its environment, dopamine surges in the organism's system and activates four other neurons in the learning circuit, giving them a greater response range. This prompts the it to search more actively in a wider area (risk-taking) until it hits a more consistent environment. The amount of dopamine in its system serves as its memory of the past experience: about 30 minutes or so and it forgets information gathered in the time before that.
While it’s been known that the presence of dopamine is tied to risk-taking behavior, how exactly dopamine does this hasn’t been well understood. With a new work, scientists now have a fundamental model of how dopamine signaling leads the organism to take more risks and explore new environments.
The connection between dopamine and risk is conserved across animals and is already known, but the new work showed mechanistically how it works. Interestingly, the scientists found that the high-threshold neurons also lead to increased signaling from a protein called CREB, known in humans and other animals to be essential to learning and retaining new memories. The researchers showed that not only are the presence of CREB important to learning, but the amount of CREB protein determines how quickly an animal learns. This surprising connection could lead to new avenues of research for brain enhancements.
When the protein CREB was present in larger amounts, the team found that the organisms took far less time to learn.
http://www.sciencedirect.com/science/article/pii/S0896627315002500
Neural Mechanisms for Evaluating Environmental Variability in Caenorhabditis elegans
C. elegans learn variability in their food environment and modify future behavior
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The authors describe the minimal circuit that evaluates environmental variability
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Dopamine levels store information about variability to regulate behavior
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The amount of CREB determines the rate of learning variability

Comment by Dr. Krishna Kumari Challa on April 11, 2015 at 7:29am

How neuro-scientists think they can do the head transplants...

The procedure starts with cooling both the body and head right down so the cells won’t die when deprived of oxgyen through the process. Next, the neck is severed and all the crucial blood vessels are hooked up to tubes while the spinal cord on both the head and the body are severed.

"The recipient's head is then moved onto the donor body and the two ends of the spinal cord – which resemble two densely packed bundles of spaghetti – are fused together,” says Thomson. "To achieve this, scientists intend to flush the area with a chemical called polyethylene glycol, and follow up with several hours of injections of the same stuff. Just like hot water makes dry spaghetti stick together, polyethylene glycol encourages the fat in cell membranes to mesh.”

Canavero told Thomson the final step would be to stitch up the muscles and blood supply, and to induce a three- or four-hour coma to let the body heal itself while embedded electrodes stimulate the spinal cord to strengthen the new nerve connections.

The recipient won’t be able to get up and walk around soon after the surgery because the damage to the spinal cord would take about 12 months to heal fully. The recipient would retain their old voice though.
But... we don’t even know if the plan to use polyethylene glycol to fuse the spinal cords is even going to work, in which case scientists will be forced to use one of their other options. There is no evidence that the connectivity of cord and brain would lead to useful sentient or motor function following head transplantation.
And... how do you get the body to stop automatically rejecting the head?

There’s no telling what the transplant - and all the new connections and foreign chemicals that the head and brain will have to suddenly deal with - will do to person’s psyche, could result in a hitherto never experienced level and quality of insanity. Scary!

- The New Scientist

Comment by Dr. Krishna Kumari Challa on April 8, 2015 at 9:05am

This topic always fascinates me... understanding the death dance...another step towards it...
Asphyxia-activated corticocardiac signaling accelerates onset of cardiac arrest
http://www.pnas.org/content/early/2015/04/02/1423936112
Death Brain Signaling Accelerates Demise of the Heart...
What happens in the moments just before death is widely believed to be a slowdown of the body’s systems as the heart stops beating and blood flow ends. For the study, performed in rats, researchers simultaneously examined the heart and brain during experimental asphyxiation and documented an immediate release of more than a dozen neurochemicals, along with an activation of brain-heart connectivity. This new laboratory study by the University of Michigan Medical School reveals a storm of brain activity that erupts as the heart deteriorates and plays a surprising destabilizing role in heart function.

This near-death brain signaling may be targeted to help cardiac arrest patients survive.
Despite the loss of consciousness and absence of signs of life, internally the brain exhibits sustained, organized activity and increased communication with the heart, which one may guess is an effort to save the heart.
However the brain signaling at near-death may, in fact, accelerate cardiac demise, according to the study published in this week’s PNAS Early Edition.

Researchers with backgrounds in engineering, neuroscience, physiology, cardiology, chemistry, and pharmacology looked at the mechanism by which the heart of a healthy person ceases to function within just a few minutes without oxygen.

While the animal study examined asphyxia-induced cardiac arrest, sudden cardiac death can also follow fatal cardiac arrhythmias, ischemic stroke, traumatic brain injury, brain hemorrhage and epilepsy.

Following a steep fall of the heart rate, brain signals strongly synchronized with the heart rhythm, as visualized beat-by-beat using a new technology developed in the Borjigin laboratory called electrocardiomatrix.

According to the study, blocking the brain’s outflow significantly delayed ventricular fibrillation, in which the lower chambers of the heart quiver and the heart cannot pump any blood. It’s the most serious cardiac rhythm disturbance.

The study suggests that a pharmacological blockade of the brain’s electrical connections to the heart during cardiac arrest may improve the chances of survival in cardiac arrest patients.
This new study provides a neurochemical foundation for the surge in brain activity and a brain-heart connectivity that may be targeted to lengthen detectable brain activity.

Comment by Dr. Krishna Kumari Challa on April 8, 2015 at 8:47am

One can develop allergies a few weeks after receiving blood transfusions
'Peanut and fish allergy due to platelet transfusion in a child'
http://www.cmaj.ca/content/early/2015/04/07/cmaj.141407
Although this is rare, an eight year old boy developed allergy toward salmon and peanut butter after the blood transfusion because the donor had these allergies. However, these allergies are short lived and dissipate after some months because the recipients themselves don't produce the allergen antibodies.
The principle behind it is Clinicians purposefully transfer antibodies to give patients protection against infections, so it is not surprising that other antibodies could be transferred and cause ripple effects. Large amounts of immunoglobulin-E (IgE) antibodies remain in blood products even after storage of more than a month. Typically, fresh frozen plasma will contain the largest amount of the antibodies, followed by platelets and then red cells because all three blood components contain plasma, which can contain antibodies.
Multiple events must come together for a patient to have this rare allergic reaction. First, the blood donor must have high levels of IgE antibodies—those that react against allergens. Second, a substantial amount of blood product must be given to the patient. Then, in order to detect the new allergy, the patient would have to be exposed to the specific allergen the antibodies would react against within a few months of receiving the transfusion. That window is tight, because passively acquired antibodies will naturally fade after a few months and the transient allergy will disappear. IgE is estimated to have a half-life of just a few hours or days, but once it enters the body and binds to cells, it can remain detectable for weeks or months and cause allergic reactions

Comment by Dr. Krishna Kumari Challa on April 7, 2015 at 8:34am

Changing human DNA permanently... well science is moving faster than ethics can catch it...

Scientists around the world are anticipating the results of a Chinese study that would mark the first time DNA in a human embryo has been modified in a way that would carry into future generations.

Although the embryos would be for study only, and not intended for implantation, the research would mark a significant milestone: the first time human DNA had been altered so substantially that it would change the “germ line” — the eggs or sperm of any child produced from the embryo.

Theoretically that could allow parents in the not-too-distant future to essentially clean their own eggs and sperm of undesired genes — such as ones known to cause cancer — and prevent those genes from being passed on to grandchildren and great-grandchildren.

Genetics research is already improving medicine, for example, informing women if they are more likely to develop breast or ovarian cancer. Scientists can sequence the human genome and parse it, find out where it goes wrong, and use that information to prevent, treat and even cure certain diseases, with implications for everything from autism to ALS.

But there’s a big difference between gene therapy — a growing field of largely clinical research that uses genes in treatment — and altering the germ line. That’s because current gene therapies make “somatic” changes to DNA, or ones that don’t affect eggs and sperm or embryos.

There are about 2,000 gene-therapy studies underway around the world. One clinical trial is seeking to turn off the genes that make the body susceptible to the HIV virus. Another pending trial out of the University of Alberta seeks to alter genes in men to stop the progression of a degenerative eye disease that leaves sufferers legally blind by middle age.

Germ-line research does get into deeper questions of eugenics, especially with spectrum disorders. We’ve got to take a deep breath because we’re about to alter the human genetic code in a way that it’s never been altered before.

However, some scientists say the fear about this kind of research is the one like we had in 1970's 'test tube babies'. Now the thing has become common. The same thing will happen to this one too.

Well...wait and watch

Comment by Dr. Krishna Kumari Challa on April 7, 2015 at 7:07am

A new exciting approach to cancer treatment : personalised cancer vaccines
Two of the most promising recent approaches to cancer treatment are immunotherapy, which harnesses the body’s own immune system to fight cancer, and personalised medicine, which involves therapeutics that are targeted to the genome of a particular patient and that patient’s cancer.

Now scientists have combined those two strategies to create a novel treatment: a vaccine developed for a single patient that triggers an immune system attack that is laser-focused on that patient’s tumours.
In the very first human trial testing this approach, the personalised vaccines successfully activated an immune response in three patients with melanoma.

The research is in its earliest stages - it’s too soon to say if the treatment actually improved survival in the patients or whether it will work in others at all. Still, scientists are excited about the idea and the proof-of-concept results, which were published in the journal Science on April 2.
In cancer, each tumour is unique, which is one reason that they can be so hard to treat. In this new approach, scientists have used that to their advantage. The broken genes that make a tumour grow out of control "can also be targeted by the immune system to control malignancies," researchers from the Netherlands Cancer Institute and Washington University School of Medicine explained.
To create the personalised treatments, scientists determined the unique genetic make-up of each patient’s melanoma tumours, which had been surgically removed. They then identified special targets, called neoantigens, on the surface of each patient’s cancer cells. Using those targets, they developed a personalised vaccine for each patient that would hopefully encourage their immune system to attack these specific neoantigens on that patient’s cancer cells.

Selecting those unique-to-the-tumour targets "helps to minimise adverse events or side effects," explained Elaine Mardis, a study co-author and researcher at the Genome Institute at the Washington University School of Medicine, on a call with reporters. The immune response triggered by the personalised vaccines is designed to behave more like a sniper than a bomb - using the neoantigens as "flags" so it can specifically taking out the cancerous cells.

Still, the process is complicated: developing each vaccine took the research team about three months - too long to wait for many cancer patients. They’re hoping a timeline of four to six weeks will become possible as they refine the process.

Even at this early and uncertain stage, scientists are encouraged by this approach because there’s a chance it could prove effective in patients who don’t respond to existing treatments. And while the trial was in melanoma, the researchers are eager to try it out on other cancers that are associated with carcinogens, like bladder, lung, and colorectal cancers.
A dendritic cell vaccine increases the breadth and diversity of melanoma neoantigen-specific T cells

http://www.sciencemag.org/content/early/2015/04/01/science.aaa3828

Comment by Dr. Krishna Kumari Challa on April 5, 2015 at 11:17am

Comment by Dr. Krishna Kumari Challa on April 4, 2015 at 6:27am

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