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Creutzfeldt-Jakob Disease (CJD)

Creutzfeldt–Jakob disease or CJD  is a degenerative neurological disorder (brain disease) that is incurable and invariably fatal. The disease is at times called a human form of Mad Cow disease given the fact that Bovine spongiform encephalopathy is the cause of variant Creutzfeldt-Jakob disease in humans.

click to see the picture

It is the most common among the types of transmissible spongiform encephalopathy found in humans. This means that the brain develops holes and takes on a sponge-like texture. This is caused by a type of infectious protein called a prion, prions are misfolded proteins which replicate by converting their properly folded counterparts.t is usually transmitted by eating contaminated beef. The disease is always fatal. There is no cure, and all treatments are experimental.

Creutzfeldt-Jakob disease captured public attention in the 1990s when individuals in the United Kingdom developed a form of the disease — variant CJD (vCJD) — after eating meat from diseased cattle. However, “classic” Creutzfeldt-Jakob disease has not been linked to contaminated beef.

Although serious, CJD is rare, and vCJD is the least common form. Worldwide, there is an estimated one case of Creutzfeldt-Jakob disease diagnosed per million people each year. In the United States there are about 200 cases per year. CJD usually appears in later life and runs a rapid course.

There are three major categories of CJD:

•Sporadic CJD: In sporadic CJD, the disease appears even though the person has no known risk factors for the disease. This is by far the most common type of CJD and accounts for at least 85% of cases.

•Hereditary CJD: In hereditary CJD, the person has a family history of the disease and/or tests positive for a genetic mutation associated with CJD. About 5 to 10% of cases of CJD in the United States are hereditary.

•Acquired CJD: In acquired CJD, the disease is transmitted by exposure to brain or nervous system tissue, usually through certain medical procedures. There is no evidence that CJD is contagious through casual contact with a CJD patient. Since CJD was first described in 1920, fewer than 1% of cases have been acquired CJD.

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CJD belongs to a family of human and animal diseases known as the transmissible spongiform encephalopathies (TSEs). Spongiform refers to the characteristic appearance of infected brains, which become filled with holes until they resemble sponges under a microscope. CJD is the most common of the known human TSEs. Other human TSEs include kuru, fatal familial insomnia (FFI), and Gerstmann-Straussler-Scheinker disease (GSS). Kuru was identified in people of an isolated tribe in Papua New Guinea and has now almost disappeared. Fatal familial insomnia and GSS are extremely rare hereditary diseases, found in just a few families around the world. Other TSEs are found in specific kinds of animals. These include bovine spongiform encephalopathy (BSE), which is found in cows and often referred to as “mad cow” disease, scrapie, which affects sheep and goats, mink encephalopathy, and feline encephalopathy. Similar diseases including chronic wasting disease (CWD) occur in elk, deer, and exotic zoo animals.

Early symptoms are as follows:-

*Memory loss
*Personality changes
*Loss of interest in life
*Impaired thinking
*Blurred vision
*Difficulty speaking
*Difficulty swallowing
*Sudden jerky movements

As the disease progresses, mental symptoms worsen. Most people eventually lapse into a coma. Heart failure, respiratory failure, pneumonia or other infections are generally the cause of death. The disease usually runs its course in about seven months, although a few people may live up to one or two years after diagnosis

The symptoms of CJD are caused by the progressive death of the brain’s nerve cells, which is associated with the build-up of abnormal prion proteins forming amyloids. When brain tissue from a CJD patient is examined under a microscope, many tiny holes can be seen where whole areas of nerve cells have died. The word “spongiform” in “transmissible spongiform encephalopathies” refers to the sponge-like appearance of the brain tissue.


Transmissible spongiform encephalopathy diseases are caused by prions. The diseases are thus sometimes called prion diseases. Other prion diseases include Gerstmann–Sträussler–Scheinker syndrome (GSS), fatal familial insomnia (FFI) and kuru in humans, as well as bovine spongiform encephalopathy (BSE, commonly known as mad cow disease) in cattle, chronic wasting disease (CWD) in elk and deer, and scrapie in sheep. Alpers’ syndrome in infants is also thought to be a transmissible spongiform encephalopathy caused by a prion.

The prion that is believed to cause Creutzfeldt–Jakob exhibits at least two stable conformations. One, the native state, is water-soluble and present in healthy cells. As of 2007[update], its biological function is presumably in transmembrane transport or signaling. The other conformational state is very poorly water-soluble and readily forms protein aggregates.

People can also acquire CJD genetically through a mutation of the gene that codes for the prion protein (PRNP). This occurs in only 5–10% of all CJD cases.

The CJD prion is dangerous because it promotes refolding of native proteins into the diseased state,[citation needed]. The number of misfolded protein molecules will increase exponentially and the process leads to a large quantity of insoluble prions in affected cells. This mass of misfolded proteins disrupts cell function and causes cell death. Mutations in the gene for the prion protein can cause a misfolding of the dominantly alpha helical regions into beta pleated sheets. This change in conformation disables the ability of the protein to undergo digestion. Once the prion is transmitted, the defective proteins invade the brain and are produced in a self-sustaining feedback loop, causing exponential spread of the prion, leading to death within a few months, although a few patients have lived as long as two years.

Stanley B. Prusiner of the University of California, San Francisco (UCSF) was awarded the Nobel Prize in physiology or medicine in 1997 for his discovery of prions. For more than a decade, Yale University neuropathologist Laura Manuelidis has been challenging this explanation for the disease. In January 2007, she and her colleagues published an article in the Proceedings of the National Academy of Science and reported that they have found a virus-like particle (but without finding nucleic acids so far) in less than 10% of the cells a scrapie-infected cell line and in a mouse cell line infected by a human CJD agent.

The risk of CJD is low. The disease can’t be transmitted through coughing or sneezing,  touching or sexual contact. The three ways it develops are:

*Spontaneously. Most people with classic CJD develop the disease for no apparent reason. CJD that occurs without explanation is termed spontaneous CJD or sporadic CJD and accounts for the majority of cases.

*By genetic mutation. In the United States, about 5 to 10 percent of people with CJD have a family history of the disease or test positive for a genetic mutation associated with CJD. This type is referred to as familial CJD.

*By contamination. A small number of people have developed CJD after being exposed to infected human tissue during a medical procedure, such as a cornea or skin transplant. Also, because standard sterilization methods do not destroy abnormal prions, a few people have developed CJD after undergoing brain surgery with contaminated instruments. Cases of CJD related to medical procedures are referred to as iatrogenic CJD. Variant CJD is linked primarily to eating beef infected with bovine spongiform encephalopathy (BSE), the medical term for mad cow disease.

Blood donor restrictions:
In 2004 a new report published in the Lancet medical journal showed that vCJD can be transmitted by blood transfusions. The finding alarmed healthcare officials because a large epidemic of the disease might arise in the near future. There is no test to determine if a blood donor is infected while in the latent phase of vCJD. In reaction to this report, the UK government banned anyone who had received a blood transfusion since January 1980 from donating blood. From 1999 there has been a ban in the UK for using UK blood to manufacture fractional products such as albumin.

Sperm donor restrictions:
In the U.S., the FDA has banned import of any donor sperm, motivated by a risk of Creutzfeldt–Jakob disease, inhibiting the once popular import of, for example, Scandinavian sperm. The risk, however, is not known, since artificial insemination has not been studied as a route of transmission. It is also not known whether prions cross the blood-testis barrier.

At present  there is no single diagnostic test for CJD. When CJD is suspected, the first concern is to rule out treatable forms of dementia such as encephalitis (inflammation of the brain) or chronic meningitis. A neurological examination and spinal tap are often performed to rule out more common causes of dementia. An electroencephalogram (EEG) to record the brain’s electrical pattern can be particularly valuable because it shows a specific type of abnormality in CJD. Computerized tomography (CT) of the brain can help rule out the possibility that the symptoms result from other problems such as stroke or a brain tumor. Magnetic resonance imaging (MRI) brain scans also can reveal characteristic patterns of brain degeneration that can help diagnose CJD.

At present, the only sure way to confirm a diagnosis of CJD is by brain biopsy or autopsy. In a brain biopsy, a neurosurgeon removes a small piece of tissue from the patient’s brain so that it can be examined by a neuropathologist. This procedure may be dangerous for the patient, and the operation does not always obtain tissue from the affected part of the brain. Because a correct diagnosis of CJD does not help the patient, a brain biopsy is discouraged unless it is needed to rule out a treatable disorder. In an autopsy, the whole brain is examined after death. More tests for CJD are under development.

Risk Factors:
Most cases of Creutzfeldt-Jakob disease occur for unknown reasons, and no risk factors can be identified. However, a few factors seem to be associated with different kinds of CJD.

*Age. Sporadic CJD tends to develop later in life, usually around the age of 60. Onset of familial CJD occurs only slightly earlier. On the other hand, vCJD has affected people at a much younger age, usually in their late 20s.

*Genetics. People with familial CJD have a genetic mutation that causes the disease. The disease is inherited in an autosomal dominant fashion, which means you need to inherit only one copy of the mutated gene, from either parent, to develop the disease. If you have the mutation, the chance of passing it on to your children is 50 percent. Genetic analysis in people with iatrogenic and variant CJD suggest that inheriting identical copies of certain variants of the prion gene may predispose a person to developing CJD if exposed to contaminated tissue.

*Exposure to contaminated tissue. People who’ve received human growth hormone derived from human pituitary glands or who’ve had dura mater grafts may be at risk of iatrogenic CJD. The risk of contracting vCJD from eating contaminated beef is difficult to determine. In general, if countries are effectively implementing public health measures, the risk is very low. For example, in the United Kingdom the current estimated risk of acquiring vCJD from beef and beef products appears to be about 1 case in 10 billion servings. The risk from beef in other high-incidence countries is estimated to be very low, as well

As with other causes of dementia, Creutzfeldt-Jakob disease profoundly affects the mind as well as the body, although CJD and its variants usually progress much more rapidly. People with CJD usually withdraw from friends and family and eventually lose the ability to recognize or relate to them in any meaningful way. They also lose the ability to care for themselves, and many eventually slip into a coma. The disease ultimately is fatal.

Physical complications, all of which may become life-threatening, include:

*Heart failure
*Respiratory failure

There is no treatment that can cure or control CJD. Researchers have tested many drugs, including amantadine, steroids, interferon, acyclovir, antiviral agents, and antibiotics. However, none of these treatments has shown any consistent benefit. Current treatment for CJD is aimed at alleviating symptoms and making the patient as comfortable as possible.


There is no known way to prevent sporadic CJD from developing. If you have a family history of neurological disease, you may benefit from talking with a genetics counselor, who can help you sort through the risks associated with your particular situation.

If you’re caring for someone with CJD or vCJD, the National Institutes of Health recommend the following basic precautions:

*Wash your hands and exposed skin before eating, drinking or smoking.
*Protect your hands and face from exposure to the person’s blood or fluids.
*Cover cuts or wounds with waterproof bandages.

Preventing iatrogenic CJD:-
Hospitals and other medical institutions follow explicit policies to prevent iatrogenic CJD. These measures have included:

*Exclusive use of synthetic human growth hormone, rather than the kind derived from human pituitary glands
*Destruction of surgical instruments used on the brain or nervous tissue of someone with known or suspected CJD
*Single-use kits for spinal taps (lumbar punctures)

You could contract CJD from an organ transplant if the donor was in the incubation stage of the disease and not yet showing signs and symptoms. However, this scenario is very unlikely. The benefits obtained from an organ transplant are generally much greater than the risk of contracting CJD.

To help ensure the safety of the blood supply, people with a risk of exposure to CJD or vCJD aren’t eligible to donate blood. This includes people who:

*Have a biological relative who has been diagnosed with CJD
*Have received a dura mater brain graft
*Have received human growth hormone
*Spent a total of at least three months in the U.K. from 1980 to 1996
*Spent five years or more in France from 1980 to the present
*Received a blood transfusion in the U.K. between 1980 and the present
*Have injected bovine insulin at any time since 1980

Preventing vCJD :
The risk of contracting vCJD in the United States remains extremely low. So far, a total of three cases have been reported in the U.S. According to the Centers for Disease Control and Prevention, strong evidence suggests that these cases were acquired abroad — two in the United Kingdom and one in Saudi Arabia.

In the United Kingdom, where the majority of vCJD cases have occurred, fewer than 200 cases have been reported. After its first appearance in 1995, CJD incidence peaked between 1999 and 2000, and has been declining since.

Regulating potential sources of vCJD :
Most countries have taken steps to prevent BSE-infected tissue from entering the food supply, including tight restrictions on importation of cattle from countries where BSE is common; restrictions on animal feed; strict procedures for dealing with sick animals; surveillance and testing methods for tracking cattle health; and restrictions on which parts of cattle can be processed for food.

The risk of vCJD from the following sources is estimated to be extremely low:

*Vaccines. Some parts of cows, including blood, enzymes and amino acids, are used to grow the bacteria and viruses needed to make certain vaccines. Not all vaccines are grown in cattle parts, however, and the Food and Drug Administration (FDA) recommends that companies producing such vaccines use cattle parts only from low-risk countries. These recommendations apply to cosmetics as well. The FDA keeps a listing on its Web site of companies that use cattle from countries that aren’t classified as low-risk.

*Insulin. Insulin sold in the United States isn’t derived from cattle, but you’re allowed to import beef insulin from other countries if you follow specific guidelines. Because there’s no way to guarantee the safety of imported insulin, talk to your doctor about the best way to obtain insulin from sources outside the United States.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.




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BPA may be Responsible for Women Infertility

Bisphenol A (BPA), which is a chemical used to harden plastic and line food containers, may be harming women’s eggs.
Evidence links exposure to the chemical to a lower quality among eggs retrieved for in vitro fertilization. A study found that as blood levels of BPA in the women studied doubled, the percentage of eggs fertilized normally declined by 50 percent.

UPI reports:

“The researchers noted BPA — found in the urine of nearly everyone tested in a 2004 U.S. analysis — is an endocrine disruptor that either mimics or blocks body hormones.”

AnnArbor.com December 16, 2010
UPI December 19, 2010
Fertility and Sterility December 4, 2010

Posted  By Dr. Marcola.Jan.3.2011

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All Wound Up

Our body wants to eat, sleep and work at specific times. Scientists now know what makes the biological clock tick, writes T.V. Jayan


All living organisms — humans are no exception — are controlled by a master clock. This biological timepiece, located in the brain, aligns an organism’s biological, behavioural and physiological activities with the day and night cycle. Its tick tock wakes us up in the morning, reminds us to eat at regular intervals and tells us when to go to bed.

But what sets this internal timekeeping, known as the circadian rhythm, has remained a mystery for long. This, despite scientists having had clues about its existence for more than a century.

The puzzle is slowly unfolding, thanks to advances in modern biology that offer a better insight into genes and their workings. Scientists now know the exact location of the master pacemaker and how is it regulated.

Research has also shown the circadian rhythm shares a reciprocal relationship with metabolism. In other words, while the circadian rhythm can influence metabolic activity, food intake can also modulate the functioning of the biological clock.

The mechanism by which feeding modulates the components of the clock machinery was discovered last month by a team of researchers led by Gad Asher of the University of Geneva. The paper, which appeared in the latest issue of Cell, shows that a protein called PARP-1 is at play here. The scientists found that mice that lack the gene that secretes PARP-1 fail to give the correct food intake cues to the circadian clock, thereby disrupting the synchronisation.

“This is an important finding,” says Raga Krishnakumar, a University of California San Francisco University researcher who, together with her former mentor W. Lee Kraus, showed early this year that PARP-1 is a multi-faceted protein that also regulates the expression of another protein which plays a vital role in aging, apart from helping contain DNA damage.

Scientists believe disruptions in the synchronisation between the circadian rhythm and metabolism play a key role in triggering many disorders that plague the modern world such as obesity, diabetes and cardiovascular diseases.

The master clock occupies a tiny area in the hypothalamus region of the brain. Called the suprachiasmatic nucleus (SCN), this brain region — the size of a grain of rice — contains a cluster of nearly 20,000 neurons. These neurons, in response to light signals received from the retina, send signals to other parts of the brain as well as the rest of the body to control a host of bodily functions such as sleep, metabolism, body temperature and hormone production.

As per the cues received through these neurons from the master clock, the cellular clocks in the tissues in different body organs are reset on a daily basis. The operation of these cellular clocks is controlled by the co-ordinated action of a limited number of core clock genes.

The year 1994 was a watershed year in research on the circadian rhythm. American Japanese scientist Joseph Takahashi, working at Northwestern University in the US, discovered the genetic basis for the mammalian circadian clock. The gene his team discovered was named CLOCK in 1997. Subsequently, scientists discovered several other genes associated with the timekeeping function such as BMAL1, PER and CRY, which are also involved in the working of the main SCN clock machinery as well as subsidiary clocks in other parts of the body.

The cues received from the master clock are important. Based on them, various genes in the cells change their expression rhythmically over a 24-hour period. It times the production of various body chemicals such as enzymes and hormones so that the body can function in an optimal fashion.

In the normal course, the body follows the master clock in setting its physiological and psychological conditions for optimal performance. While the 24-hour solar cycle is the main cue for resetting the master clock — just like a wall-mounted clock resets after a 24-hour cycle — there are other time cues as well: food intake, social activity, temperature and so on. “Unlike geophysical time, the biological clock does not follow an exact 24-hour cycle on its own. Various external and internal time cues that it receives play a vital role in bringing the periodicity close to 24 hours,” says Vijay Kumar Sharma of the Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, who has been studying the circadian rhythm for years.

However , modern society often imposes deviations from the regular work-rest cycle. “Basically, mammals including humans are diurnal (active during the day rather than at night). Whatever be the external compulsions (night shifts or partying late), the inner mechanisms of the body follow a diurnal pattern,” says Sharma. “It is bound to be out of sync if we deviate from the routine.”

“A major consequence of modern lifestyle is the disruption of the circadian rhythm. This leads to a number of pathological conditions, including sleep disturbances, depression, metabolic disorders and cancer. Studies reveal the risk of breast cancer is significantly higher in industrialised societies, and that the risk increases as developing countries become more and more westernised. Moreover, a moderate increase in the incidence of breast cancer is reported in women working nightshifts,” says Sourabh Sahar, a researcher working on the circadian rhythm at the University of California, Irvine.

Need more proof that the body has a mind of its own?

Source: The Telegraph (Kolkata, India)

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Exercise ‘Can Fight Ageing’

Long-term physical activity has an anti-ageing effect at the cellular level, a German study suggests.
…..click & see

Exercise seems to stimulate a key enzyme
Researchers focused on telomeres, the protective caps on the chromosomes that keep a cell’s DNA stable but shorten with age.

They found telomeres shortened less quickly in key immune cells of athletes with a long history of endurance training.

The study, by Saarland University, appears in the journal Circulation.

In a separate study of young Swedish men, cardiovascular fitness has been linked to increased intelligence and higher educational achievement.

Telomeres are relatively short sections of specialised DNA that sit at the ends of all our chromosomes.

They have been compared to the plastic tips at the ends of shoelaces that prevent the laces from unravelling.

Each time a cell divides, its telomeres shorten and the cell becomes more susceptible to dying.

National athletes:-
The researchers measured the length of telomeres in blood samples from two groups of professional athletes and two groups of people who were healthy non-smokers, but who did not take regular exercise.

One group of professional athletes included members of the German national track and field athletics team, who had an average age of 20.

The second group was made up of middle-aged athletes who had regularly run long distances – an average of 80km a week – since their youth.

The researchers found evidence that the physical exercise of the professional athletes led to activation of an enzyme called telomerase, which helped to stabilise telomeres.

This reduced the telomere shortening in leukocytes, a type of white blood cell that plays a key role in fighting infection and disease.

The most pronounced effect was found in athletes who had been regularly endurance training for several decades.

Potency of training:

Lead researcher Dr Ulrich Laufs said: “This is direct evidence of an anti-ageing effect of physical exercise.

“Our data improves the molecular understanding of the protective effects of exercise and underlines the potency of physical training in reducing the impact of age-related disease.”

Professor Tim Spector, an expert on genetics and ageing at Kings College London, said other studies had suggested more moderate exercise had a beneficial effect on ageing.

He said: “It is still difficult to separate cause and effect from these studies – as longer telomeres may still be a marker of fitness.

“Nevertheless – this is further evidence that regular exercise may retard aging.”

Professor Kay-Tee Khaw, of the University of Cambridge, an expert on ageing, said: “The benefits of physical activity for health are well established from many large long-term population studies.

“Even moderate levels of physical activity are related to lower levels of many heart disease risk factors such as blood pressure and cholesterol and lower risk of many chronic diseases associated with ageing such as heart disease, stroke, diabetes and some cancers.”


Intelligence link…….>In the second study, published in Proceeding of the National Academy of Sciences, a team from the University of Gothenburg analysed data on more than 1.2 million Swedish men born from 1950-1976 who enlisted for military service at age 18.

They found that good heart health was linked to higher intelligence, better educational achievement and raised status in society.

By studying twins in the study, the researchers concluded that environmental and lifestyle factors were key, rather than genetics.

They said the findings suggested that campaigns to promote physical exercise might help to raise standards of educational achievement across the population.

Lead researcher Professor Georg Kuhn said cardiovascular exercise increased blood flow to the brain, which in turn might help forge more and stronger connections between nerve cells.

However, he said it was also possible that intelligent people tended to make more exercise.

You may Click to see:->
Mutant genes ‘key to long life’
Nobel prize for chromosome find.
Hope for test to measure ageing.
Clean living ‘slows cell ageing’.
Healthy living ‘can add 14 years’.
Vitamin D ‘may help slow ageing’.

Source: BBC News :4th .Jan.2010

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Waking up Dormant HIV

World HIV/AIDS Awareness Day
Image by reflexblue via Flickr

HAART (highly active anti-retroviral therapy) has emerged as an extremely effective HIV treatment that keeps virus levels almost undetectable; however, HAART can never truly eradicate the virus as some HIV always remains dormant in cells. But, a chemical called suberoylanilide hydroxamic acid (SAHA), recently approved as a leukemia drug, has now been shown to ‘turn on’ latent HIV, making it an attractive candidate to weed out the hidden virus that HAART misses.
Matija Peterlin at UCSF and colleagues had previously identified another chemical called HMBA that could activate latent HIV, but the risk of several toxic side effects made HMBA clinically non-viable. However, the chemically similar SAHA had received FDA approval, making it a potentially safer alternate.

So, the researchers examined whether SAHA had any effect on HIV latency. They found that SAHA could indeed stimulate latent HIV to begin replicating, which exposes the infected cell to HAART drugs. SAHA could activate HIV in both laboratory cells as well as from blood samples taken from HIV patients on antiretroviral therapy. Importantly, this successful activation was achieved using clinical doses of SAHA, suggesting toxicity will not be a problem.