Tag Archives: Johns Hopkins University

A/C in Car – Precautions

Do not turn on A/C immediately as soon as you enter the car. Open the windows after you enter your car and turn ON the air-conditioning after a couple of minutes.

click & see

According to a research done, the car dashboard, sofa, air freshener emits Benzene, a Cancer causing toxin (carcinogen – take note of the heated plastic Smell in your car).

In addition to causing cancer, it poisons your bones, causes anemia, and reduces white blood cells. Prolonged exposure will cause Leukemia, increasing the risk of cancer. May also cause miscarriage.

Acceptable Benzene level indoors is 50 mg per sq. ft… A car parked indoors with the windows closed will contain 400-800 mg of Benzene.
If parked outdoors under the sun at a temperature above 60 degrees F, the Benzene level goes up to 2000-4000 mg, 40 times the acceptable level… & the people inside the car will inevitably inhale an excess amount of the toxins.

It is recommended that you open the windows and door to give time for the interior to air out before you enter. Benzene is a toxin that affects your kidney and liver, and is very difficult for your body to expel this toxic stuff.

Advertisements

Dengue Virus Growth Protein Identified

A TEM micrograph showing Dengue virus virions ...

Image via Wikipedia

Products from Amazon.com

By silencing genes one by one, scientists have identified dozens of proteins that help the dengue fever virus to grow and spread among  mosquitoes and humans. The research paves the way to potentially prevent or treat the disease, which infects millions worldwide every year.

Dengue is a mosquito-borne illness that can cause debilitating sickness and death. “Dengue is a nasty disease, and right now, there is no treatment for it and no way to prevent it,” said Mariano Garcia-Blanco, professor of molecular genetics and microbiology at Duke University Medical Centre (DUMC) and study co-author.

“But if we can find a weakness in the virus, we can design a strategy to fight it. This study has helped us identify some gaps in dengue’s armour,” he said.

Almost half the people in the world are vulnerable to the dengue virus, says the World Health Organisation. Public health officials are worried because dengue appears to be popping up in places where it has rarely appeared before. It may be fuelled by global warming.

Garcia-Blanco, used RNA interference (RNAi) to unlock dengue’s secrets. RNA interference is a normal biological process cells use to turn gene expression on or off depending upon which gene products, or proteins, are needed at any given moment.

“That very same system proved to be the perfect investigative tool for our study,” said Garcia-Blanco.

Garcia-Blanco and colleagues in Duke’s RNAi facility were able to knock down gene function in fruit fly cells infected with a strain of the dengue virus known as DENV-2.

Silencing one gene at a time allowed researchers to pinpoint which genes, or host factors, were essential to viral growth and which ones were not.

They used fruit flies as a model because the genetic tools needed for the same work in mosquitoes have not been developed as yet. The process yielded 116 host factors that appeared to be important for successful dengue infection in fruit flies.

In testing several of these host factors in mosquitoes at Johns Hopkins University, researchers subsequently discovered that at least one – and possibly a second – was necessary for dengue infection to occur in the insects, said a DUMC release.

Sources: The Times Of India

Reblog this post [with Zemanta]

New Chemical Alternative to MSG That is Coming Soon

For anyone who’s ever wanted the savory taste of meats and cheeses without actually having to eat them, chemists have identified molecular mechanisms underlying the sensation of umami, also known as the fifth taste.

…………………CLICK & SEE.
The historically unappreciated taste is produced by two interacting sets of molecules, each of which is needed to trigger cellular receptors on your tongue’s surface.

“This opens the door to designing better, more potent and more selective umami enhancers,” said Xiaodong Li, a chemist at San Diego-based food-additive company Senomyx.

Four other basic tastes — bitter, sweet, salty and sour — were identified 2,400 years ago by the Greek philosopher Democritus, and became central to the western gastronomic canon.

In the late 19th century, French chef and veal-stock inventor Auguste Escoffier suggested that a fifth taste was responsible for his mouth-watering brew. Though Escoffier’s dishes were popular, his theories were dismissed until 1908, when Japanese chemist Kikunae Ikeda showed that an amino acid called glutamate underlies the taste of a hearty variety of seaweed soup.

In honor of Ikeda, the taste was dubbed umami, the Japanese word for delicious. It took another 80 years for umami to be recognized by science as comparable to the other four tastes.

In the meantime, monosodium glutamate became wildly popular as a flavor enhancer. But MSG can cause headaches and dizziness, and has been tenuously linked to long-term neurological disorders.

“The only way to have a substitute is to find the molecular target of glutamate. If we figure that out, then we can screen for agents that are not glutamate but could mimic it,” said Johns Hopkins University neuroscientist Solomon Snyder, who was not involved in the new study.

Li’s team have taken human kidney cells and added the genes for receptors linked to umami taste. Receptors form on the cells’ surface, geometrically resembling the mouth of a Venus flytrap. When glutamate is caught on a receptor’s lips and a molecule called ribonucleotide lodged in its throat, the receptor snaps shut.

“The configuration of the receptor changes, sending a signal down into the cell,” said Li. In their engineered and disconnected cells the signal quickly fizzled — but in a tongue surface cell, said Li, “Your brain gets a signal: Something tastes good that is in my mouth.”
Sources:

WIRED December 22, 2008
Proceedings of the National Academy of Sciences December 22, 2008

Reblog this post [with Zemanta]

How Light Sensors in Eye Work

Neuro-scientists have unravelled how newly discovered light sensors in the eye detect light and communicate with the brain.
click & see

These light sensors are a small number of nerve cells in the retina that contain melanopsin molecules.

Unlike conventional light-sensing cells in the retina-rods and cones, melanopsin-containing cells are not used for seeing images.

Instead, they monitor light levels to adjust the body’s clock and control constriction of the pupils in the eye, among other functions.

“These melanopsin-containing cells are the only other known photoreceptor besides rods and cones in mammals, and the question is, how do they work,” said Michael Do, a postdoctoral fellow in neuro-science at Johns Hopkins.

“We want to understand some fundamental information, like their sensitivity to light and their communication to the brain,” he informed.

Using mice, the team first tested the light sensitivity of these cells by flashing light at the cells and recording the electrical current generated by one cell.

They found that these cells are very insensitive to light, in contrast to rods, which are very sensitive and therefore enable us to see in dim light at night, for example.

According to Do, the melanopsin-containing cells are less sensitive than cones, which are responsible for our vision in daylight.

“The next question was, what makes them so insensitive to light? Perhaps each photon they capture elicits a tiny electrical signal. Then there would have to be bright light-giving lots of captured photons for a signal large enough to influence the brain. Another possibility is that these cells capture photons poorly,” said Do.

To figure this out, the team flashed dim light at the cells. The light was so dim that, on average, only a single melanopsin molecule in each cell was activated by capturing a photon.

They found that each activated melanopsin molecule triggered a large electrical signal. Moreover, to their surprise, the cell transmits this single-photon signal all the way to the brain, said a Johns Hopkins release.

Yet the large signal generated by these cells seemed incongruous with their need for such bright light. “We thought maybe they need so much light because each cell might also contain very few melanopsin molecules, decreasing their ability to capture photons,” said King-Wai Yau, a professor of neuroscience at Hopkins.

When they did the calculations, the research team found that melanopsin molecules are 5,000 times sparser than other light-capturing molecules used for image-forming vision.

“It appears that these cells capture very little light. However, once captured, the light is very effective in producing a signal large enough to go straight to the brain,” said Yau.

Sources: The Telegraph (Kolkata, India)

Reblog this post [with Zemanta]

How to Help a Depressed Loved One

Don’t tell him to “snap out of it.” There are better ways to deal with depression.
The most important thing you can do for a family member or friend who is depressed is to help him or her get an appropriate diagnosis and treatment. This may involve encouraging him or her to stay with treatment until symptoms begin to abate (several weeks), or to seek different treatment if no improvement occurs. On occasion, it may require making an appointment and accompanying your loved one to the doctor. It may also mean monitoring whether he is taking medication. Encourage your friend to obey the doctor’s orders about the use of alcoholic products while on medication.

The second most important thing is to offer emotional support. This involves understanding, patience, affection, and encouragement. Engage the depressed person in conversation and listen carefully. Do not disparage feelings expressed, but point out realities and offer hope. Do not ignore remarks about suicide. Report them to your friend’s therapist. Invite your friend for walks, outings, to the movies, and other activities. Be gently insistent if your invitation is refused. Encourage participation in some activities that once gave the person pleasure, such as hobbies, sports, religious or cultural activities, but do not push him to undertake too much too soon. Your friend or family member needs diversion and company, but too many demands can increase feelings of failure.

Do not accuse your friend of faking illness or of laziness, or expect her “to snap out of it.” Eventually, with treatment, most people do get better. Keep that in mind, and keep reassuring her that, with time and help, she will feel better.

Where to Get Help:
If you’re unsure where to go for help, check the Yellow Pages under “mental health,” “health,” “social services,” “suicide prevention,” “crisis intervention services,” “hotlines,” “hospitals,” or “physicians” for phone numbers and addresses. You can also search the websites listed under “Related Links.” People and places that will make referrals to, or provide, diagnostic and treatment services include: family doctors, community mental health centers, hospital psychiatry departments and outpatient clinics, university- or medical school-affiliated programs, family service or social agencies, employee assistance programs, and local medical and/or psychiatric societies. In times of crisis, the emergency room doctor at a hospital may be able to provide temporary help for an emotional problem, and will be able to tell you where and how to get further help.

From: The National Institute of Mental Health