SCIENCE & TECHNOLOGY

Unlocked: the secrets of schizophrenia
Scientific breakthrough offers hope of new treatments for mental condition
A colour enhanced MRI image of the brain shows one of the theories into what may be the chemical basis for Schizophrenia. Researchers have found reduced receptors for dopamine in the brain (areas colourized)

Prof Yash Pal

Prof Yash Pal

Prof Yashpal
This Universe
If we take a magnet in the shape of a perfect cube, it’s one side will act as a north pole and the opposite side as the south pole. Then what will be the polarities on the other four sides? Will those sides not attract each other if another cube magnet is placed near it? How will we decide which of the three adjacent sides of a cube is north pole or south pole?”

Nuclear medicine: a possible cure to blood cancer
Last month, Dr. A. Lagaru from the Division of Nuclear Medicine at Stanford University Medical Centre and his colleagues won the Society of Nuclear Medicine (SNM) 2009 Image of the Year award in Toronto.

Trends
Genetic analysis reveals what makes us look old
London: A genetic analysis of human skin has revealed what makes us look old, say American scientists. According to scientists, the finding could throw up ways to smooth away wrinkles and provide a quantifiable way to test claims made for skin products, reports New Scientist.

 


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Unlocked: the secrets of schizophrenia
Scientific breakthrough offers hope of new treatments for mental condition
By Steve Connor

An enhanced MRI image of the brain shows one of the theories into what may be the chemical basis for Schizophrenia. Researchers have found reduced receptors for dopamine in the brain.
An enhanced MRI image of the brain shows one of the theories into what may be the chemical basis for Schizophrenia. Researchers have found reduced receptors for dopamine in the brain.

A colour enhanced MRI image of the brain shows one of the theories into what may be the chemical basis for Schizophrenia. Researchers have found reduced receptors for dopamine in the brain (areas colourized)

Scientists have discovered a remarkable similarity between the genetic faults behind both schizophrenia and manic depression in a breakthrough that is expected to open the way to new treatments for two of the most common mental illnesses, affecting millions of people.

Previously doctors had assumed that the two conditions were quite separate. But new research shows for the first time that both have a common genetic basis that leads people to develop one or other of the two illnesses.

Three different international studies investigated the genetic basis of schizophrenia by pooling their analysis of about 15,000 patients and nearly 50,000 healthy subjects to find that thousands of tiny genetic mutations – known as single nucleotide polymorphisms (SNPs) – are operating in raising the risk of developing the illness.

Each mutation on its own increased the risk of developing schizophrenia by about 0.2 per cent but collectively they were found to account for at least a third of the total risk of developing schizophrenia. The condition is known to have a strong inherited component, accounting for about 80 per cent of the total risk, but it is also influenced by upbringing and environment.

However, one of the most surprising findings to emerge from the three studies was that the same array of genetic variations in SNPs was also linked with bipolar disorder, a discovery that is at odds with the orthodoxy in psychiatry stating that the two conditions are clinically distinct, the scientists said. The findings are a milestone in the understanding of both schizophrenia and manic depression – also known as bipolar disorder – which could eventually lead to new ways of either preventing or treating conditions that cause untold human misery and cost the NHS hundreds of millions of pounds each year.

“If some of the same genetic risks underlie schizophrenia and bipolar disorder, perhaps these disorders originate from some common vulnerability in brain development,” said Thomas Insel, director of the US National Institute for Mental Health in Bethesda, Maryland, which part-funded the studies. “Of course the big question then is how some people develop schizophrenia and others develop bipolar disorder.”

Although the schizophrenia studies have so far only identified a handful of the many thousands of genetic variations implicated in the mental illness, scientists believe it represents a breakthrough that will accelerate the understanding of the condition and the development of new drugs and treatments. “This is a pretty major breakthrough for us because before today you could count on the thumb of one hand the number of common [genetic] variants that have been reliably identified for schizophrenia,” said Michael O’Donovan, professor of psychiatric genetics at the Medical Research Council’s neurogenetics centre in Cardiff.

“However, what we’ve found so far explains only a tiny fraction of the total risk of schizophrenia. Some of us were surprised to find that not only did these genes contribute to schizophrenia but they also contribute to bipolar disorder. So that really suggests that the two disorders are not really as distinct as we thought in psychiatry.”

The three studies, published in the journal Nature, have been possible because of technical advances in the analysis of the genomes of patients, enabling scientists to rifle through vast amounts of DNA in order to make comparisons between patients and healthy “controls”.

Eric Lander, the founding director of the consortium of 11 research centres in the United States, Europe and Australia behind the studies, and a member of Barack Obama’s Council of Advisers on Science and Technology, said that the pace of research into schizophrenia was accelerating fast. “Over the past year, using techniques designed to study common DNA changes, psychiatric disease geneticists have detected more statistically compelling findings than in the previous 100 years,” he said.

— By arrangment with The Independent

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Prof Yashpal
This Universe

If we take a magnet in the shape of a perfect cube, it’s one side will act as a north pole and the opposite side as the south pole. Then what will be the polarities on the other four sides? Will those sides not attract each other if another cube magnet is placed near it? How will we decide which of the three adjacent sides of a cube is north pole or south pole?”

The magnets you are familiar with are produced by aligning the microscopic magnetic domains of a magnetic material. We assign magnetic moments even to individual charged particles whenever they have a spin angular momentum. Nuclei of atoms also have spins. Think of them as tiny magnets that, in a non-magnetised state of the bulk material, are randomly oriented. Magnetisation is a process of alignment. Therefore, for a magnet in a spherical shape, the poles would be positioned depending on the way the sphere was magnetised. It might happen, though, that in an irregular shaped material, internal interaction between domains might produce a localised unpredictability in the magnetic field.

Sound is produced due to vibrations that occur when air passes through the voice box in the throat. Then why do people have different voices?

The air passing through our larynx vibrates our vocal cords. The natural frequency of their vibration depends on their thickness and other physical features. Man-made resonance cavities can pick and enhance various harmonics, with the range of this capability depending on their construction. All drums do not give the same note, nor do all bells. It is truly amazing what gifted musicians can do with the relatively simple sound-making system with which we are all endowed. Perhaps it is not so simple.

It is easily understood that the sounds and music made by different individuals cannot be the same. People are not constructed exactly the same on the outside. That is why no two persons look exactly the same; they are recognisable as being different. Similarly, slight differences in the sound-making apparatus (including physical measurements and sizes and shapes of resonant cavities) are not surprising. These variations result in recognisably different voices. Another level of complexity arises due to the fact that speaking or singing is also a learnt art. The way we manipulate our tongue or lips also makes a huge difference to our oral output, as does the extent and dexterity of breath control that a musician manages to acquire.

Readers wanting to ask Prof Yash Pal a question can e-mail him at palyash.pal@gmail.com

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Nuclear medicine: a possible cure to blood cancer
By Dr KS Parthasarathy

Last month, Dr. A. Lagaru from the Division of Nuclear Medicine at Stanford University Medical Centre and his colleagues won the Society of Nuclear Medicine (SNM) 2009 Image of the Year award in Toronto.

Their poster paper contained an image clearly depicting how radio-immunotherapy can successfully treat non Hodgins Lymphoma (NHL), a potentially fatal form of blood cancer. The US National Cancer Institute estimates that in 2009, 65,980 new cases of NHL will be diagnosed in the US leading to 19,500 deaths.

“Radio-immunotherapy is a form of personalised medicine that combines the cancer fighting ability of radiation therapy with the precise targeting capacity of immunotherapy” (Imaging technology, June 16,2009). It is based on the body’s natural defence system, which protects it from many diseases.

The Stanford group studied two immunotherapy agents Bexxar, which is Iodine-131 based and Zevalin, which is Yttrium-90 based. Iodine-131 and Yttrium-90 are radioactive and emit particulate radiation. The immunotherapy agents home in on the cancerous cells, which become sitting targets for the particulate radiation emitted by Iodine-131 or Yttrium-90 as the case may be. The award-winning image is two sets of before and after Positron Emission Tomography scans of two patients, one treated with Bexxar and the other with Zevalin. Both patients did not show any metabolically active cancer as early as three months after treatment as demonstrated by their PET scans.

A PET scanner uses small amounts of certain radioactive drugs. A special camera that works with a computer provides pictures of the area of the body being imaged. Cancer cells grow and multiply uncontrollably. While doing so, they consume enormous amounts of energy. Basically, this energy comes from burning glucose

Cancer cell metabolise sugar at higher rates than normal cells. Fluoro deoxyglucose (FDG) is a marker for sugar metabolism. It contains Fluorine-18, a positron emitting radionuclide, whose presence will help to trace and locate the sites where FDG molecules get accumulated. Cancerous areas draw higher amounts of FDG, an ideal marker for the disease and its spread. PET scans produce three-dimensional images of the precise location of FDG in the body

“The image of the year was chosen because it shows how molecular therapy can cure non Hodgin’s lymphoma and it provides objective evidence that the patient has been cured”, Dr Henry N, Wagner Jr, a professor of environmental sciences at Johns Hopkins University and past president of the SNM clarified. The Stanford Specialists treated 71 patients. They showed that both the immunotherapy agents are safe and effective in treating non Hodgin’s lymphoma, even in cases where the disease has spread extensively. Twenty four out of 35 patients responded to Bexxar; 28 out of 36 to Zevalin. Taken the two groups together, 27 showed complete response to the drugs. However, in 19 patients the disease progressed in spite of treatment.

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Trends
Genetic analysis reveals what makes us look old


An aerial view of an area damaged by tin mining is seen near housing complexes in Indonesia’s Bangka island.
An aerial view of an area damaged by tin mining is seen near housing complexes in Indonesia’s Bangka island. The scale of the environmental damage on the Bangka-Belitung islands can be most clearly seen from the air, revealing a lunar landscape of craters and hundreds of highly acidic, turquoise lakes created by centuries of largely unregulated tin mining. — Reuters

London: A genetic analysis of human skin has revealed what makes us look old, say American scientists. According to scientists, the finding could throw up ways to smooth away wrinkles and provide a quantifiable way to test claims made for skin products, reports New Scientist.

Rosemary Osborne of Procter and Gamble in Cincinnati, Ohio, and colleagues used DNA microarrays, common in the drugs industry, to measure the expression of thousands of genes in skin of different ages.

Energy intake reaches a limit despite abundant food supply

Washington: Contradicting Charles Darwin’s theory, scientists have now shown that despite abundant food supply, energy intake reaches a limit even in animals with high nutrient demands, such as lactating females. Darwin and his contemporaries postulated that food consumption in birds and mammals was limited by resource levels, which meant that animals would eat as much as they could while food was plentiful and produce as many offspring as this would allow them to.

Scientists at the Research Institute of Wildlife Ecology in Vienna have now suggested that energy intake reaches a limit due to active control of maternal investment in offspring in order to maintain long-term reproductive fitness.

That indicated that, ordinarily, the hares were operating at below their maximum capacity. — ANI



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