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Comment by Dr. Krishna Kumari Challa on August 20, 2014 at 11:22am

Bypassing The Brain To Walk Again
Bypassing the spinal cord with an artificial neural connection enables subjects to control their legs by swinging their arms.
A Japanese research group has successfully made an artificial connection from the brain to the locomotion center, bypassing the spinal cord with a computer interface. This research, published in the Journal of Neuroscience, allowed subjects to perform a walking-like behavior in their legs by swinging their arms.
Neural networks in the locomotion center of the spinal cord are capable of producing rhythmic movements, such as swimming and walking, even when isolated from the brain. The brain controls the spinal locomotion center by sending commands to the spinal locomotion center to start, stop and change waking speed. In most cases of spinal cord injury, the loss of this link from the brain to the locomotion center causes problems with walking.
Although gait disturbance in individuals with spinal cord injury is attributed to the interruption of neural pathways from brain to the spinal locomotor center, neural circuits located above and below the lesion maintain most of their functions. An artificial connection that bridges the lost pathway and connects brain to spinal circuits has potential to ameliorate the functional loss.
http://www.ncbi.nlm.nih.gov/pubmed/25122909

Comment by Dr. Krishna Kumari Challa on August 20, 2014 at 11:08am

Asthma and odors: The role of risk perception in asthma exacerbation
Fragrances and strong odors have been characterized as putative triggers that may exacerbate asthma symptoms and many asthmatics readily avoid odors and fragranced products. However, the mechanism by which exposure to pure, non-irritating odorants can elicit an adverse reaction in asthmatic patients is still unclear and may involve both physiological and psychological processes. The aim of this study was to investigate how beliefs about an odor's relationship to asthmatic symptoms could affect the physiological and psychological responses of asthmatics.
Results

Predictably, manipulations of perceived risk altered both the quality ratings of the fragrance as well as the reported levels of asthma symptoms. Perceived risk also modulated the inflammatory airway response.
Conclusions

Expectations elicited by smelling a perceived harmful odor may affect airway physiology and impact asthma exacerbations.
Highlights

•Asthmatics were exposed to an odor characterized as ‘asthmogenic’ or ‘therapeutic’.

•Irritation and annoyance ratings were elevated in the asthmogenic group.

•The asthmogenic group showed a rapid and persistent increase in airway inflammation.
http://www.jpsychores.com/article/S0022-3999%2814%2900252-9/abstract

Comment by Dr. Krishna Kumari Challa on August 20, 2014 at 10:49am

Comment by Dr. Krishna Kumari Challa on August 20, 2014 at 10:47am

All babies lack sufficient vitamin K at birth, putting them at risk for severe bleeding in the brain or intestines until they get the vitamin by eating solid foods, typically around six months of age. The vitamin is essential for blood clotting, and a vitamin K injection after birth eliminates this bleeding risk.
Therefore, Vitamin K injections are recommended at birth in some countries because the vitamin does not cross the placenta well during pregnancy. The shot provides infants with enough vitamin K to last until they get sufficient amounts through diet. Vitamin K deficiency bleeding has always occurred but for years the condition was less common than other causes of infant death.

http://pediatrics.aappublications.org/content/112/1/191.full

Comment by Dr. Krishna Kumari Challa on August 19, 2014 at 8:39am

Genomic-scale exchange of mRNA between a parasitic plant and its hosts
Abstract: Movement of RNAs between cells of a single plant is well documented, but cross-species RNA transfer is largely unexplored. Cuscuta pentagona (dodder) is a parasitic plant that forms symplastic connections with its hosts and takes up host messenger RNAs (mRNAs). We sequenced transcriptomes of Cuscuta growing on Arabidopsis and tomato hosts to characterize mRNA transfer between species and found that mRNAs move in high numbers and in a bidirectional manner. The mobile transcripts represented thousands of different genes, and nearly half the expressed transcriptome of Arabidopsis was identified in Cuscuta. These findings demonstrate that parasitic plants can exchange large proportions of their transcriptomes with hosts, providing potential mechanisms for RNA-based interactions between species and horizontal gene transfer.
http://www.sciencemag.org/content/345/6198/808
What this means: A vampire-like parasitic plant could reveal new secrets of plant communication. According to a study published Thursday in Science, species of the strangleweed plant are able to share genetic information in the form of messenger RNA molecules (mRNA) with the plants they invade. It's possible that this RNA shuffling is allowing for communication between the parasite and the host, and if we crack their codes we could exploit them to protect crops.

Comment by Dr. Krishna Kumari Challa on August 19, 2014 at 8:18am

Comment by Dr. Krishna Kumari Challa on August 19, 2014 at 8:18am

Comment by Dr. Krishna Kumari Challa on August 19, 2014 at 6:23am

Releasing genetically engineered fruit flies into the wild could prove to be a cheap, effective and environmentally friendly way of pest control, a new study has found.

New research by scientists at the University of East Anglia and Oxitec Ltd shows the release of genetically engineered male flies could be used as an effective population suppression method - saving crops around the world.

The Mediterranean fruit fly is a serious agricultural pest which causes extensive damage to crops.
The genetically engineered flies are not sterile, but they are only capable of producing male offspring after mating with local pest females - which rapidly reduces the number of crop-damaging females in the population.
This method presents a cheap and effective alternative to irradiation. This is a promising new tool to deal with insects which is both environmentally friendly and effective.
The method works by introducing a female-specific gene into the insects that interrupts development before females reach a reproductive stage.

Populations of healthy males and females can be produced in controlled environments by the addition of a chemical repressor.

If the chemical repressor is absent in the genetically engineered flies' diet, only males survive.

The surviving males are released, mate with local wild pest females and pass the female specific self-limiting trait onto the progeny resulting in no viable female offspring.

The research was published in the journal Proceedings of the Royal Society B.

Comment by Dr. Krishna Kumari Challa on August 12, 2014 at 6:47am

Partial Recovery From Disorders of Consciousness
Traumatic Brain Injury Patients Treated with Anti-Spasm Agent Partially Recover from Disorders of Consciousness

At the International Neuromodulation Society’s 11th World Congress, Dr. Stefanos Korfias of the Department of Neurosurgery at the University of Athens will present the results of a clinical study led by Professor Damianos Sakas, which showed that two of six in-patients studied at Evangelismos Hospital in Athens steadily emerged from minimally conscious state after receiving intrathecal baclofen (ITB) after traumatic brain injury.

The drug relaxes spasticity that can result from brain injury and may be used to facilitate care, but is not normally used to restore function. The patients, a 24-year-old man and a 29-year-old man, had been in minimally conscious states for three years and 18 months, respectively. Their scores on a revised coma recovery scale (with a maximum of 23) increased from 10 – 19 and 11 – 22, respectively
http://www.newswise.com/articles/partial-recovery-from-disorders-of...
Electrical Brain Stimulation Can Restore Consciousness
Mild electrical stimulation might help brain-damaged patients communicate
http://www.scientificamerican.com/article/electrical-brain-stimulat...

Comment by Dr. Krishna Kumari Challa on August 9, 2014 at 9:21am

Two species of birds — carrion crows, which predominate in western Germany, and the closely related hooded crows that prevail further to the east, in Sweden and Poland can mate with each other, but they look very different — carrion crows are black, and hooded crows have black-and-gray bodies — and the birds strongly prefer mates of their own kind. For a long as anyone can remember, the two groups have remained distinct, save for a narrow band of habitat stretching from Denmark through eastern Germany to northern Italy where they sometimes intermingle.

The crows present a puzzling question to biologists, which gets to the heart of what it means to be a species: Given that hooded and carrion crows can mate and swap genes, how do the two groups maintain their individual identities? It’s as if you mixed red and yellow paint in a bucket but the two colors stubbornly refused to make orange.

In new research published in June in the journal Science, Wolf’s ( an Evolutionary Biologist) team has found that a surprisingly small chunk of DNA may hold the answer. A comparison of the carrion and hooded-crow genomes showed that the sequences are almost identical. Differences in just 82 DNA letters, out of a total of about 1.2 billion, appear to separate the two groups. Almost all of them are clustered in a small part of one chromosome. “Maybe just a few genes make a species what they are,” said Chris Jiggins, a biologist at the University of Cambridge in England, who was not involved in the study. “Maybe the rest of genome can flow, so species are much more fluid than we imagined before.”

The findings are striking because they suggest that just a few genes can keep two populations apart. Something within that segment of DNA stops black crows from mating with gray ones and vice versa, creating a tenuous mating barrier that could represent one of the earliest steps in the formation of new species. “They look very different and prefer to mate with their own kind, and all of that must be controlled by these narrow regions,” Jiggins said.
http://www.ncbi.nlm.nih.gov/pubmed/24948738
http://www.simonsfoundation.org/quanta/20140805-as-animals-mingle-a...

Crows aren’t alone in their behavio

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