Serotonin Syndrome
posted by Louis Brothnias @ 10:36 AM
0 comments
Friday, November 24, 2006
Monday, November 20, 2006
Statins
The following is not original - accredited to: MedicineNet.
Pyramid Comment: Diabetes, Statins and NICE
Statin Withdrawal
Statin Dangers
"Statins" are a class of drugs that lowers the level of cholesterol in the blood by reducing the production of cholesterol by the liver. Statins block the enzyme in the liver that is responsible for making cholesterol. This enzyme is called hydroxy-methylglutaryl-coenzyme A reductase (HMG-CoA reductase for short). Scientifically, statins are called HMG-CoA reductase inhibitors. Cholesterol is critical to the normal function of every cell in the body. However, it also contributes to the development of atherosclerosis, a condition in which cholesterol-containing plaques form within the arteries. These plaques block the arteries and reduce the flow of blood to the tissues the arteries supply. When plaques rupture, a blood clot forms on the plaque, thereby further blocking the artery and reducing the flow of blood. When blood flow is reduced sufficiently in the arteries that supply blood to the heart, the result is angina (chest pain) or a heart attack. If the clot occurs on plaques in the brain, the result is a stroke. Clots occurring on plaques in the leg cause intermittent claudication (pain in the legs while walking). By reducing the production of cholesterol, statins are able to reduce the formation of new plaques and occasionally can reduce the size of plaques that already exist. In addition, through mechanisms that are not well understood, statins also stabilize plaques and make them less prone to rupturing and forming clots. Although the important role of cholesterol in atherosclerosis is widely accepted by scientists, research also shows that atherosclerosis is a complex process that involves more than just cholesterol. For example, scientists have discovered that inflammation in the walls of the arteries may be an important factor in atherosclerosis. New research shows that statins reduce inflammation, which could be another mechanism by which statins beneficially affect atherosclerosis. This reduction of inflammation does not depend on statins' ability to reduce cholesterol. Further, these anti-inflammatory effects can be seen as early as two weeks after starting statins.
For what conditions are statins used?
Statins are used for preventing and treating atherosclerosis that causes chest pain, heart attacks, strokes, and intermittent claudication in individuals who have or are at risk for atherosclerosis. Risk factors for atherosclerosis include abnormally elevated cholesterol levels, a family history of heart attacks (particularly at a young age), increasing age, and diabetes. Most individuals are placed on statins because of high levels of cholesterol. Though cholesterol reduction is important, heart disease is complex and, as discussed previously, other factors such as inflammation may play a role. Thirty-five percent of individuals who develop heart attacks do not have high blood cholesterol levels, yet most of them have atherosclerosis. This means that high levels of cholesterol are not always necessary for atherosclerotic plaques to form. Because it is not clear which effect of statins is responsible for their benefits, the goal of treatment with statins should not be only the reduction of cholesterol to normal levels, but rather the prevention of the complications of atherosclerosis-angina, heart attacks, stroke, intermittent claudication, and death. This concept is important because it allows for individuals who have or are at risk for atherosclerosis, but do not have high levels of cholesterol, to be considered for treatment with statins. Statins, like ACE inhibitors, are an important class of drugs because some of these drugs have been shown to reduce the incidence of heart attacks, strokes, and death.
Are there differences among statins?
Statins differ in several ways. The most obvious difference is in their ability to reduce cholesterol. Currently, atorvastatin (Lipitor) is the most potent and fluvastatin (Lescol) is the least potent. A new statin, rosuvastatin (Crestor), which is under development, may be more potent than atorvastatin. The statins also differ in how strongly they interact with other drugs. For example, pravastatin levels in the body are less likely to be elevated by other drugs because the enzymes in the liver that eliminate pravastatin (unlike the enzymes that eliminate other statins) are not blocked by most other drugs. Another difference is that only three of the statins (pravastatin, simvastatin, and lovastatin) have been shown in large studies to actually reduce heart attacks. In addition, simvastatin and pravastatin have demonstrated the ability to reduce death. Pravastatin also reduces the occurrence of strokes. Interestingly, these three statins are derived from natural sources and have similar chemical structures. The other statins are completely synthetic and have chemical structures that differ greatly from the natural statins. Statins differ in the frequency with which they cause a rare side effect called rhabdomyolysis, in which muscles are damaged. Cerivastatin (Baycol) was withdrawn from pharmacies worldwide because it causes rhabdomyolysis more often than other statins. In contrast, the results from three large studies of pravastatin and over ten years of experience with pravastatin have proven that pravastatin is safe. Finally, statins also differ in how they affect fibrinogen, a protein that is important in the clotting of blood and the growth of smooth muscle cells (which, like inflammation, also may be involved in atherosclerosis). The importance of this difference is unclear. However, in view of the complexity of the process of atherosclerosis and the possibility that the beneficial effects of statins are due to effects other than their lowering of cholesterol, these differences could be quite important. Moreover, since it is not yet clear exactly how statins bring about their beneficial effects, it is important to demonstrate that each statin reduces heart attacks, strokes, and deaths in addition to comparing their effects. One such study now underway is comparing the effects of pravastatin and atorvastatin in reducing heart attacks, strokes, and death.
What are the side effects of statins?
Statins have few important side effects. The most common side effects are headache, nausea, vomiting, constipation, diarrhea, headache, rash, weakness, and muscle pain. The most serious (but fortunately rare) side effects are liver failure and rhabdomyolysis. Rhabdomyolysis is a serious side effect in which there is damage to muscles. Rhabdomyolysis often begins as muscle pain and can progress to loss of muscle cells, kidney failure, and death. It occurs more often when statins are used in combination with other drugs that themselves cause rhabdomyolysis or with drugs that prevent the elimination of statins and raise the levels of statins in the blood. Since rhabdomyolysis may be fatal, unexplained joint or muscle pain that occurs while taking statins should be brought to the attention of a healthcare provider for evaluation.
With which drugs do statins interact?
Statins have some important drug interactions. The first type of interaction involves the elimination of statins by the liver. Liver enzymes (specifically the cytochrome P-450 liver enzymes) are responsible for eliminating all statins from the body with the exception of pravastatin. Therefore, drugs that block the action of these liver enzymes increase the levels of simvastatin, lovastatin, fluvastatin, and atorvastatin (but not pravastatin) in the blood and can lead to the development of rhabdomyolysis. Drugs or agents that block these enzymes include protease inhibitors (used in treating AIDS), erythromycin, itraconazole, clarithromycin, diltiazem, verapamil, and grapefruit juice. Another important drug interaction occurs between statins and niacin or fibric acids, e.g., gemfibrozil (Lopid), clofibrate (Atromid-S), and fenofibrate (Tricor). Fibric acids and niacin can cause rhabdomyolysis or liver failure when used alone and combining them with statins increases the likelihood of rhabdomyolysis or liver failure. Nevertheless, fibric acids and niacin are often used with caution in combination with most statins. Cholestyramine (Questran) as well as colestipol (Colestid) bind statins in the intestine and reduce their absorption into the body. To prevent this binding within the intestine, statins should be taken one hour before or four hours after cholestyramine or colestipol.
Which statins are available?
Statins that are approved for use in the United States include:
- atorvastatin (Lipitor)
- fluvastatin (Lescol)
- lovastatin (Mevacor)
- pravastatin (Pravachol)
- rosuvastatin (Crestor)
- simvastatin (Zocor)
- pitavastatin (Livalo)
posted by Louis Brothnias @ 12:05 PM
0 comments
Sunday, November 19, 2006
Death of the Autopsy
New Scientist.
13th November, 2006
Doctors occasionally kill their patients instead of curing them. It’s not a secret and this may be by prescribing the wrong drug. Serious efforts are now being made to reduce medical errors, but the focus is almost entirely on avoiding mistakes in treatment, rather than in the original diagnosis. Major mistakes in diagnosis do happen, and they are surprisingly common. It is estimated that as many as 1 in 20 patients who die in hospital, do so because their illness was misdiagnosed.
The best way of uncovering diagnostic errors (autopsy) is in steep decline. If a misdiagnosis is not suspected, then evidence will be buried or cremated with the body, and nobody will be any the wiser. There is nothing to stop the same mistakes being made over and over again. "Diagnostic errors do not receive the attention they deserve," says Kaveh Shojania of the University of Ottawa in Canada, who studies medical errors. "It is a big part of the problem."
The value of autopsies was established during the 18th and 19th centuries and today remains the gold standard as a way for doctors to identify and learn from their mistakes. It is much easier to find out for sure what was wrong with someone after their death as pathologists can cut open the body, examine any part in detail and take samples for testing.
Suspicious circumstances
Some forensic or coroners' autopsies have to be done for legal reasons and are often where the cause is unclear or are required after violent, accidental or suspicious deaths.
Sometimes, doctors just want to know more about why someone died.
One of the first large studies (1912) compared hospital autopsy results with the initial diagnosis. After looking at 3000 cases it became clear that nearly half the diagnoses had been wrong. Today's performance seems little better and a recent review of similar studies since the 1960s concluded that the certified causes of death were wrong in at least a third of cases. At least 10 per cent of autopsies show patients might have lived had their diagnosis been right and, although not all the errors would have affected survival, some would.
Health policies are often based on death certificate statistics.
The conclusion was reached that the accuracy of diagnoses has been improving steadily, with the rate of major discrepancies affecting survival falling by a third each decade (Journal of the American Medical Association, vol 289, p 2849). However, the death rate remains high. At least 4 per cent of all US patients who die in hospital might have survived had their diagnosis been right. The figure is higher in other countries.
Even in today's era of high-tech medicine, some errors are inevitable. Doctors have limited knowledge, limited tools and limited time to make a diagnosis and even well-studied diseases can produce strange symptoms unlike those in the textbooks. Patients can also have several diseases at once. It is sometimes not possible to work out what is wrong with a patient while they are alive, and not always possible when they are dead either. "It's a miracle how often doctors get it right," says Mark Graber of the Veterans Affairs Medical Center in Northport, New York.
An important cause of error was mistakes by individual doctors and these ranged from lack of medical knowledge to using flawed reasoning to reach their diagnosis. The commonest type of error is "premature closure": a doctor arrives at a diagnosis that seems to fit the facts, then stops considering other possibilities. Some doctors gave every sign of sheer incompetence, such as failing to pass on test results or even skipping parts of a physical examination. Whatever the cause of misdiagnoses, nothing can be done about them if they are never discovered. And the only sure way to detect more diagnostic errors is to do more autopsies. Whether it be flawed reasoning or faulty equipment, "No lesson is as powerful as seeing your own mistakes," says Graber.
The number of autopsies is in decline and clinicians don't think it necessary to conduct them. And it's no longer part of training. Cash-strapped public healthcare systems often decide the money is better spent elsewhere and private hospitals cannot charge relatives for autopsies so they have little incentive either. Another possible cause is increasing fear of litigation, but some argue that such worries are groundless. A recent study of US appeals court records showed that the crucial factor in law is not whether an autopsy reveals a discrepancy, but whether the misdiagnosis was due to negligence. "It is not necessary to be right," says lead author Kevin Bove of Children's Hospital Medical Center in Cincinnati. "You just have to do the right thing."
Others argue that doctors may not request autopsies in cases where they suspect they could be held liable for negligence.
Then there is the issue of getting consent from relatives. In the UK, there was public revulsion in 1999 on the discovery that a pathologist at Alder Hey Children's Hospital in Liverpool had stored thousands of organs from children's autopsies without their parents' knowledge. There have been similar public outcries about stored organs in Australia and Ireland. "Some doctors are now frightened to ask for consent," says Emyr Benbow, a pathologist at the University of Manchester in the UK. An audit at University Hospitals of Leicester before and after the Alder Hey scandal revealed the hospital autopsy rate had dropped from 10 per cent to less than 1 per cent.
The main cause was not that relatives were refusing consent; it was that doctors were less likely to ask for it.
Protection from lawsuits would be unlikely to go down well with an increasingly litigious public, but if doctors keep quiet about misdiagnoses, as may happen now, there is no chance of improving matters. Ideally, autopsies would be carried out on a random sample of people who die. In the US, hospitals once had to have a minimum autopsy rate of 20 per cent, but this was abandoned in 1970. In the UK, the Royal College of Pathologists once considered trying to push for a minimum 10 per cent random autopsy rate, but the Alder Hey scandal kicked the idea into touch. "There would be a substantial outcry," says Benbow.
If one of your family dies and a doctor suggests an autopsy, give permission.
Anatomy of an autopsy
The pathologist first examines the outside of the body. Then they make a large Y-shaped incision from the shoulders to mid-chest and down to the groin. There is almost no bleeding as the heart has stopped beating and there is no blood pressure.
The flesh is pulled back so the doctor can cut away and remove the breastbone and ribs to allow access to the chest cavity. They remove all the major organs, such as the heart and lungs, and many smaller ones such as the thyroid gland, for weighing and further examination. The stomach contents are checked for any drugs or poisons, and many tissue samples are preserved so they can be inspected under the microscope. If the brain needs examining, the pathologist cuts open the scalp from ear to ear and peels back the skin. Then they saw off the top of the skull to remove the brain.
At the end, all the organs except those portions that need to be saved may be returned to the body cavity, and the flesh is sewn up. The scalp incision will be concealed by the pillow when the dead person is in their coffin, so relatives will see no visible reminder of the autopsy.
Based on an article by Clare Wilson
13th November, 2006
Doctors occasionally kill their patients instead of curing them. It’s not a secret and this may be by prescribing the wrong drug. Serious efforts are now being made to reduce medical errors, but the focus is almost entirely on avoiding mistakes in treatment, rather than in the original diagnosis. Major mistakes in diagnosis do happen, and they are surprisingly common. It is estimated that as many as 1 in 20 patients who die in hospital, do so because their illness was misdiagnosed.
The best way of uncovering diagnostic errors (autopsy) is in steep decline. If a misdiagnosis is not suspected, then evidence will be buried or cremated with the body, and nobody will be any the wiser. There is nothing to stop the same mistakes being made over and over again. "Diagnostic errors do not receive the attention they deserve," says Kaveh Shojania of the University of Ottawa in Canada, who studies medical errors. "It is a big part of the problem."
The value of autopsies was established during the 18th and 19th centuries and today remains the gold standard as a way for doctors to identify and learn from their mistakes. It is much easier to find out for sure what was wrong with someone after their death as pathologists can cut open the body, examine any part in detail and take samples for testing.
Suspicious circumstances
Some forensic or coroners' autopsies have to be done for legal reasons and are often where the cause is unclear or are required after violent, accidental or suspicious deaths.
Sometimes, doctors just want to know more about why someone died.
One of the first large studies (1912) compared hospital autopsy results with the initial diagnosis. After looking at 3000 cases it became clear that nearly half the diagnoses had been wrong. Today's performance seems little better and a recent review of similar studies since the 1960s concluded that the certified causes of death were wrong in at least a third of cases. At least 10 per cent of autopsies show patients might have lived had their diagnosis been right and, although not all the errors would have affected survival, some would.
Health policies are often based on death certificate statistics.
The conclusion was reached that the accuracy of diagnoses has been improving steadily, with the rate of major discrepancies affecting survival falling by a third each decade (Journal of the American Medical Association, vol 289, p 2849). However, the death rate remains high. At least 4 per cent of all US patients who die in hospital might have survived had their diagnosis been right. The figure is higher in other countries.
Even in today's era of high-tech medicine, some errors are inevitable. Doctors have limited knowledge, limited tools and limited time to make a diagnosis and even well-studied diseases can produce strange symptoms unlike those in the textbooks. Patients can also have several diseases at once. It is sometimes not possible to work out what is wrong with a patient while they are alive, and not always possible when they are dead either. "It's a miracle how often doctors get it right," says Mark Graber of the Veterans Affairs Medical Center in Northport, New York.
An important cause of error was mistakes by individual doctors and these ranged from lack of medical knowledge to using flawed reasoning to reach their diagnosis. The commonest type of error is "premature closure": a doctor arrives at a diagnosis that seems to fit the facts, then stops considering other possibilities. Some doctors gave every sign of sheer incompetence, such as failing to pass on test results or even skipping parts of a physical examination. Whatever the cause of misdiagnoses, nothing can be done about them if they are never discovered. And the only sure way to detect more diagnostic errors is to do more autopsies. Whether it be flawed reasoning or faulty equipment, "No lesson is as powerful as seeing your own mistakes," says Graber.
The number of autopsies is in decline and clinicians don't think it necessary to conduct them. And it's no longer part of training. Cash-strapped public healthcare systems often decide the money is better spent elsewhere and private hospitals cannot charge relatives for autopsies so they have little incentive either. Another possible cause is increasing fear of litigation, but some argue that such worries are groundless. A recent study of US appeals court records showed that the crucial factor in law is not whether an autopsy reveals a discrepancy, but whether the misdiagnosis was due to negligence. "It is not necessary to be right," says lead author Kevin Bove of Children's Hospital Medical Center in Cincinnati. "You just have to do the right thing."
Others argue that doctors may not request autopsies in cases where they suspect they could be held liable for negligence.
Then there is the issue of getting consent from relatives. In the UK, there was public revulsion in 1999 on the discovery that a pathologist at Alder Hey Children's Hospital in Liverpool had stored thousands of organs from children's autopsies without their parents' knowledge. There have been similar public outcries about stored organs in Australia and Ireland. "Some doctors are now frightened to ask for consent," says Emyr Benbow, a pathologist at the University of Manchester in the UK. An audit at University Hospitals of Leicester before and after the Alder Hey scandal revealed the hospital autopsy rate had dropped from 10 per cent to less than 1 per cent.
The main cause was not that relatives were refusing consent; it was that doctors were less likely to ask for it.
Protection from lawsuits would be unlikely to go down well with an increasingly litigious public, but if doctors keep quiet about misdiagnoses, as may happen now, there is no chance of improving matters. Ideally, autopsies would be carried out on a random sample of people who die. In the US, hospitals once had to have a minimum autopsy rate of 20 per cent, but this was abandoned in 1970. In the UK, the Royal College of Pathologists once considered trying to push for a minimum 10 per cent random autopsy rate, but the Alder Hey scandal kicked the idea into touch. "There would be a substantial outcry," says Benbow.
If one of your family dies and a doctor suggests an autopsy, give permission.
Anatomy of an autopsy
The pathologist first examines the outside of the body. Then they make a large Y-shaped incision from the shoulders to mid-chest and down to the groin. There is almost no bleeding as the heart has stopped beating and there is no blood pressure.
The flesh is pulled back so the doctor can cut away and remove the breastbone and ribs to allow access to the chest cavity. They remove all the major organs, such as the heart and lungs, and many smaller ones such as the thyroid gland, for weighing and further examination. The stomach contents are checked for any drugs or poisons, and many tissue samples are preserved so they can be inspected under the microscope. If the brain needs examining, the pathologist cuts open the scalp from ear to ear and peels back the skin. Then they saw off the top of the skull to remove the brain.
At the end, all the organs except those portions that need to be saved may be returned to the body cavity, and the flesh is sewn up. The scalp incision will be concealed by the pillow when the dead person is in their coffin, so relatives will see no visible reminder of the autopsy.
Based on an article by Clare Wilson
posted by Louis Brothnias @ 1:29 PM
0 comments
Wednesday, November 15, 2006
Genes Record Orangutans' Decline
Deforestation has had a huge impact on orangutan numbers. The dramatic collapse of orangutan populations has been linked to human activity, genetic evidence shows.
The orangutan is one of the three species (along with chimpanzee and Human) that has self-awareness.
And the claim is that the Human species is responsible for the orangutan's impending demise.
Such irony.
Researchers report that a population crash occurred during the past 200 years, coinciding with deforestation in the same area. The study focuses on orangutans found in the forests of Kinabatangan Wildlife Sanctuary in Malaysia. Writing in the journal Plos Biology, researchers suggest that the outlook is "bleak" unless urgent action is taken.
The team looked at 200 orangutans living along the Kinabatangan river. These animals are confined to fragmented patches of forest. By collecting the orangutans' hair and faeces, the researchers were able to extract DNA to create genetic profiles, which could then be used to study genetic diversity of the population, which shows a very strong signal of a massive population decline.
"This was interesting because we didn't expect it to show that the decline has happened so recently - within the last 200 years."
The period in which the population collapse occurred correlates strongly with the time that post-colonial habitat exploitation began in the region.
When north Borneo became part of the British Empire in the late 19th Century, deforestation began in earnest. In recent years, conservationists have linked the orangutans' decline to forest clearance for palm oil plantations, which produce the raw materials used for products like lipstick and soap. However, the Malaysian authorities told the BBC in November that the plantations were mainly grown on land that had already been cultivated or in "secondary jungle".
Environmental impact studies were also carried out before any plantations were established.
Orangutan numbers are now put at just 50,000, according to The World Atlas of Great Apes and their Conservation which is published by the UN's environment and biodiversity agencies. Professor Bruford warns that the animals' habitat needs to be better preserved, and that steps should be taken to re-establish corridors between fragmented forest patches.
He says it may even be necessary to move orangutans around to prevent inbreeding.
"The important thing you have to remember is that Kinabatangan is just one area, but these problems are significant in all orangutan ranges. If we don't put these changes in place throughout, then the outlook is really very bleak indeed," he urged.
The orangutan is one of the three species (along with chimpanzee and Human) that has self-awareness.
And the claim is that the Human species is responsible for the orangutan's impending demise.
Such irony.
Researchers report that a population crash occurred during the past 200 years, coinciding with deforestation in the same area. The study focuses on orangutans found in the forests of Kinabatangan Wildlife Sanctuary in Malaysia. Writing in the journal Plos Biology, researchers suggest that the outlook is "bleak" unless urgent action is taken.
The team looked at 200 orangutans living along the Kinabatangan river. These animals are confined to fragmented patches of forest. By collecting the orangutans' hair and faeces, the researchers were able to extract DNA to create genetic profiles, which could then be used to study genetic diversity of the population, which shows a very strong signal of a massive population decline.
"This was interesting because we didn't expect it to show that the decline has happened so recently - within the last 200 years."
The period in which the population collapse occurred correlates strongly with the time that post-colonial habitat exploitation began in the region.
When north Borneo became part of the British Empire in the late 19th Century, deforestation began in earnest. In recent years, conservationists have linked the orangutans' decline to forest clearance for palm oil plantations, which produce the raw materials used for products like lipstick and soap. However, the Malaysian authorities told the BBC in November that the plantations were mainly grown on land that had already been cultivated or in "secondary jungle".
Environmental impact studies were also carried out before any plantations were established.
Orangutan numbers are now put at just 50,000, according to The World Atlas of Great Apes and their Conservation which is published by the UN's environment and biodiversity agencies. Professor Bruford warns that the animals' habitat needs to be better preserved, and that steps should be taken to re-establish corridors between fragmented forest patches.
He says it may even be necessary to move orangutans around to prevent inbreeding.
"The important thing you have to remember is that Kinabatangan is just one area, but these problems are significant in all orangutan ranges. If we don't put these changes in place throughout, then the outlook is really very bleak indeed," he urged.
posted by Louis Brothnias @ 10:49 AM
0 comments
Tuesday, November 14, 2006
Aspartame
Updated: 2nd July 2023
Aspartame: Bressler Report
Aspartame: Dangers Of Aspartame Poisoning
Aspartame: Effects On Health
Aspartame/Pentagon - biochemical warfare agent
Aspartame: Side Effects
Aspartame: Warning
Aspartame: What You Don't Know Can Hurt You
American Dietetic Association
Comment (Pyramid)
Equal (Merisant Company)
Neotame
FDA Website Search Results For Aspartame (26.11.06)
Holland Sweetener Company (Exits Aspartame Business)
Life After Aspartame (The Ecologist)
Neotame
Nutrasweet
The reason for HSC withdrawal: the global aspartame markets are facing structural oversupply, which has caused worldwide strong price erosion over the last 5 years. This has resulted in a persistently unprofitable business position for HSC. No significant improvements are expected in the near or foreseeable future. The decision to withdraw from this business is in line with DSM's Vision 2010 - Building on Strengths strategy, in which profitable innovative growth and value creation are key objectives.
Shame it's only for business health (profit) reasons and not human health reasons.
- On January 9, 2009, Merisant filed for Chapter 11 bankruptcy protection
FDA Website Search Results For Aspartame (26.11.06)
Holland Sweetener Company (Exits Aspartame Business)
Life After Aspartame (The Ecologist)
Neotame
Nutrasweet
The reason for HSC withdrawal: the global aspartame markets are facing structural oversupply, which has caused worldwide strong price erosion over the last 5 years. This has resulted in a persistently unprofitable business position for HSC. No significant improvements are expected in the near or foreseeable future. The decision to withdraw from this business is in line with DSM's Vision 2010 - Building on Strengths strategy, in which profitable innovative growth and value creation are key objectives.
Shame it's only for business health (profit) reasons and not human health reasons.
posted by Louis Brothnias @ 2:29 PM
0 comments
Acetylcholine
Neurotransmitters are chemicals that are used to relay, amplify and modulate electrical signals between a neuron and another cell.
Types of neurotransmitters:
* Acetylcholine - voluntary movement of the muscles
* Norepinephrine - wakefulness or arousal
* Dopamine - voluntary movement and emotional arousal
* Serotonin - memory, emotions, wakefulness, sleep, temperature regulation
* GABA - (Gamma AminoButyric Acid) motor behaviour
* Glycine - spinal reflexes and motor behaviour
* Neuromodulators - sensory transmission-especially pain
Types of neurotransmitters:
* Acetylcholine - voluntary movement of the muscles
* Norepinephrine - wakefulness or arousal
* Dopamine - voluntary movement and emotional arousal
* Serotonin - memory, emotions, wakefulness, sleep, temperature regulation
* GABA - (Gamma AminoButyric Acid) motor behaviour
* Glycine - spinal reflexes and motor behaviour
* Neuromodulators - sensory transmission-especially pain
posted by Louis Brothnias @ 12:55 PM
0 comments
Acupuncture
Acupuncture 'deactivates the brain'. The science associated with some phenomena does not need to be understood in order to accept it. It is the difference between ‘mainstream’ and ‘complementary’ medicine.
Acupuncture-caused brain activity over and above a simple skin prick and works by deactivating the area of the brain governing pain. Volunteers are subjected to deep needling, which involves needles being inserted 1cm into the back of the hand at well-known acupuncture points. A control group undergoes superficial needling with needles placed only 1mm in. The needles are then twiddled until the participants feel a dull, achy or tingling sensation. For those in the deep needling group this stimulates the nervous system. During these two procedures, the volunteers underwent brain scans to see what, if any, effect there was in the brain.
The team, including leading scientists from University College London, Southampton University and the University of York, found the superficial needling resulted in activation of the motor areas of the cortex, a normal reaction to pain. But with deep needling, the limbic system, part of the pain matrix, is deactivated. The finding was surprising because experts had always assumed acupuncture activates the brain in someway.
Professor Sykes said: "The pain matrix is involved in the perception of pain - it helps someone decide whether something is painful or not, so it could be that acupuncture in some ways changes a person's pain perception. "We have found something quite unexpected - that acupuncture is having a measurable effect on the human brain. We are not suggesting that it should be used during surgery, although it is in China, but just that it acts as a pain relief and should be taken seriously."
Professor Tony Wildsmith, a pain relief expert at the University of Dundee, said he thought the findings were possible. But he added: "The thing about acupuncture is that it does not work on everyone. It is more likely to be effective if you believe it. "I think it is a psychological manipulation technique, a distraction. We are not going to get to the stage where this could be used instead of a general anaesthetic."
It seems that Tony Wildsmith has already made up his mind - not particularly scientific, ahead of any evidence. Whether it is psychological or not, if it works, and by whatever mechanism, it must surely be taken seriously.
Such examples of the unexplained should not be rejected just because they can’t be understood. It is possible that the mechanism by which it could be explained hasn’t yet been discovered. There is less doubt these days that there is some connection between positive thinking and the immune system. It isn’t understood, but it is being accepted that there is some link between the psychological and the physiological.
Acupuncture-caused brain activity over and above a simple skin prick and works by deactivating the area of the brain governing pain. Volunteers are subjected to deep needling, which involves needles being inserted 1cm into the back of the hand at well-known acupuncture points. A control group undergoes superficial needling with needles placed only 1mm in. The needles are then twiddled until the participants feel a dull, achy or tingling sensation. For those in the deep needling group this stimulates the nervous system. During these two procedures, the volunteers underwent brain scans to see what, if any, effect there was in the brain.
The team, including leading scientists from University College London, Southampton University and the University of York, found the superficial needling resulted in activation of the motor areas of the cortex, a normal reaction to pain. But with deep needling, the limbic system, part of the pain matrix, is deactivated. The finding was surprising because experts had always assumed acupuncture activates the brain in someway.
Professor Sykes said: "The pain matrix is involved in the perception of pain - it helps someone decide whether something is painful or not, so it could be that acupuncture in some ways changes a person's pain perception. "We have found something quite unexpected - that acupuncture is having a measurable effect on the human brain. We are not suggesting that it should be used during surgery, although it is in China, but just that it acts as a pain relief and should be taken seriously."
Professor Tony Wildsmith, a pain relief expert at the University of Dundee, said he thought the findings were possible. But he added: "The thing about acupuncture is that it does not work on everyone. It is more likely to be effective if you believe it. "I think it is a psychological manipulation technique, a distraction. We are not going to get to the stage where this could be used instead of a general anaesthetic."
It seems that Tony Wildsmith has already made up his mind - not particularly scientific, ahead of any evidence. Whether it is psychological or not, if it works, and by whatever mechanism, it must surely be taken seriously.
Such examples of the unexplained should not be rejected just because they can’t be understood. It is possible that the mechanism by which it could be explained hasn’t yet been discovered. There is less doubt these days that there is some connection between positive thinking and the immune system. It isn’t understood, but it is being accepted that there is some link between the psychological and the physiological.
posted by Louis Brothnias @ 2:32 AM
0 comments
Tuesday, November 07, 2006
Defense by Smell and Taste
A genetically programmed survival mechanism exists that has anything smelling offensive probably being harmful. A taste defense also exists to protect us from harmful foods/substances (unless cynically masked by the use of salt).
Salt is one way to make fat taste palatable.
In an opposite sense, our taste provides us with essential amino acids in food, though we are unaware of any selection by taste.
There are two main sources of dietary protein - animal and vegetable. Each has many of the necessary amino acids, but protein from vegetable sources has in some cases less of the essential amino acids. This does not mean that the quality of non-animal protein should be underestimated. A combination of two or more types of non-animal protein may complement one another by providing sufficient amounts of all.
Cereals are generally high in methionine and tryptophan but low in lysine. Pulses on the other hand are low in methionine and tryptophan but have a high lysine content. Between them all three amino acids are available in quantity in beans on toast.
Man's natural palette puts together good combinations of foods.
Salt is one way to make fat taste palatable.
In an opposite sense, our taste provides us with essential amino acids in food, though we are unaware of any selection by taste.
There are two main sources of dietary protein - animal and vegetable. Each has many of the necessary amino acids, but protein from vegetable sources has in some cases less of the essential amino acids. This does not mean that the quality of non-animal protein should be underestimated. A combination of two or more types of non-animal protein may complement one another by providing sufficient amounts of all.
Cereals are generally high in methionine and tryptophan but low in lysine. Pulses on the other hand are low in methionine and tryptophan but have a high lysine content. Between them all three amino acids are available in quantity in beans on toast.
Man's natural palette puts together good combinations of foods.
posted by Louis Brothnias @ 2:45 AM
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The Big Bang
- the description of "process at the Big Bang when the hot-dense universe acted as a giant thermonuclear reactor converting hydrogen to helium with traces of deuterium and lithium" doesn't explain where this element originated, yet this gas is everywhere. Hydrogen is the simplest atomic combination known: a single proton with one associated electron and makes up the 'atmosphere' (or interstellar medium) of galaxies. This is both the source of clouds that create new stars and the repository of gas outflow from existing stars. Locally, this 'atmosphere' is more extensive than the visible Milky Way and governs its development by determining where new stars will form and their composition.
Big Bang Expanded
posted by Louis Brothnias @ 2:32 AM
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Deforestation Consequences
Deforestation has had a huge impact on orangutan numbers. The dramatic collapse of orangutan populations has been linked to human activity, new genetic evidence shows. Ironically, the orangutan is one of the ten species that has self-awareness. And the claim is that the Human species is responsible for the orangutan's impending demise. Researchers report that a population crash occurred during the past 200 years, coinciding with deforestation in the same area. The study focuses on orangutans found in the forests of Kinabatangan Wildlife Sanctuary in Malaysia. Writing in the journal Plos Biology, researchers suggest that the outlook is "bleak" unless urgent action is taken.
The team looked at 200 orangutans living along the Kinabatangan river. These animals are confined to fragmented patches of forest. By collecting the orangutans' hair and faeces, the researchers were able to extract DNA to create genetic profiles, which could then be used to study genetic diversity of the population, which shows a very strong signal of a massive population decline.
The period in which the population collapse occurred correlates strongly with the time that post-colonial habitat exploitation began in the region. When north Borneo became part of the British Empire in the late 19th Century, deforestation began in earnest. In recent years, conservationists have linked the orangutans' decline to forest clearance for palm oil plantations, which produce the raw materials used for products like lipstick and soap. However, the Malaysian authorities told the BBC in November that the plantations were mainly grown on land that had already been cultivated or in "secondary jungle". Environmental impact studies were also carried out before any plantations were established, they added.
Orangutans numbers are now put at just 50,000 according to The World Atlas of Great Apes and their Conservation which is published by the UN's environment and biodiversity agencies. The animals' habitat needs to be better preserved and steps should be taken to re-establish corridors between fragmented forest patches. It may even be necessary to move orangutans around to prevent inbreeding.
The team looked at 200 orangutans living along the Kinabatangan river. These animals are confined to fragmented patches of forest. By collecting the orangutans' hair and faeces, the researchers were able to extract DNA to create genetic profiles, which could then be used to study genetic diversity of the population, which shows a very strong signal of a massive population decline.
"This was interesting because we didn't expect it to show that the decline has happened so recently - within the last 200 years."
The period in which the population collapse occurred correlates strongly with the time that post-colonial habitat exploitation began in the region. When north Borneo became part of the British Empire in the late 19th Century, deforestation began in earnest. In recent years, conservationists have linked the orangutans' decline to forest clearance for palm oil plantations, which produce the raw materials used for products like lipstick and soap. However, the Malaysian authorities told the BBC in November that the plantations were mainly grown on land that had already been cultivated or in "secondary jungle". Environmental impact studies were also carried out before any plantations were established, they added.
Orangutans numbers are now put at just 50,000 according to The World Atlas of Great Apes and their Conservation which is published by the UN's environment and biodiversity agencies. The animals' habitat needs to be better preserved and steps should be taken to re-establish corridors between fragmented forest patches. It may even be necessary to move orangutans around to prevent inbreeding.
"The important thing you have to remember is that Kinabatangan is just one area, but these problems are significant in all orangutan ranges. If we don't put these changes in place throughout, then the outlook is really very bleak indeed."
posted by Louis Brothnias @ 2:13 AM
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Sniffing in Stereo
I wrote this 27th April 2005
(see: The Pyramid)
- We can hear in stereo, or rather hear a sound image in two parts. This allows the awareness of direction. We see images in two parts allowing depth of field to be judged. Without this benefit, we could not assess distance. We have two ears and two eyes.
- Do we detect odours in stereo?
- We have two nostrils. How does the brain interpret different smells. A chiral molecule is in essence much like the left and right hands: mirror images, but otherwise identical. Two such molecules may have a very different odour, though otherwise be identical. The olfactory organs can distinguish such a difference to a very high degree.
Rat brain 'can smell in stereo'
Rats could locate the source of a smell with one or two sniffs. Rats can home in on smells using a method similar to the stereo processing of sounds, scientists say. Indian experts found 90% of neurons in the olfactory bulb of the rodent's brain respond differently to smells coming from the left and right. Details of the study appear in the latest issue of the journal Science.
The rats needed only one or two sniffs to accurately locate the source of an odour, the University of Agricultural Science, Bangalore, team reports. For rats, "each sniff is a perceptually complete snapshot of the olfactory world, including both odour identity and stereo-based location," Raghav Rajan and colleagues write in Science. The researchers got lab rats to stick their noses in holes in their cages to pick up odours sprayed from either the left or the right. If the smell came from the left, the rats would receive a water reward by licking the spout on the left. The same would apply if the smell came from the right. The rats were able to accurately determine which direction the odour came from in as little as 50 milliseconds.
The researchers say the rat's stereo sense of smell gives it an evolutionary advantage: allowing it to locate food or predators more quickly and precisely.
This may answer my own question
posted by Louis Brothnias @ 2:08 AM
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Class A Drugs
As class A drugs, heroin, cocaine, ecstasy and magic mushrooms are very potent. Alcohol is in the top five of the most harmful drugs, alongside heroin and cocaine. This also includes barbiturates and methadone.
Ecstasy and LSD are both class A drugs and, in terms of harmful effects, come well below tobacco (nicotine) and alcohol.
Alcohol Warning Labels
posted by Louis Brothnias @ 1:58 AM
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Wind Power
Apparently, some 72 trillion watts (72,000,000,000,000) of electricity could be generated by wind power at sites identified by Stanford University. Researchers mapped 1000 locations worldwide where the wind could power a turbine.
Wind power could supply more than 5 times the Earth's energy needs.
A combination of oil (hence petrol) to fuel cars and wind generated electricity would solve many problems instantly.
Wind power could supply more than 5 times the Earth's energy needs.
A combination of oil (hence petrol) to fuel cars and wind generated electricity would solve many problems instantly.
posted by Louis Brothnias @ 1:36 AM
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Ethos
This is intended for entries of a science-based nature. They are mostly for my own interest, but are left as they could be of interest to others.
I am a scientist
I practise wordcraft
I develop/manage blogs (web logs) = Journals
What I do care about is the translation of this 'fact' into "must be explicit and disturbing" without checking. Very amateurish. Public or private defamatory and libelous statements are actionable. This is why I am very careful about what I publish in the public domain.
Occasionally, a self-promoted web moderator (policeman) decides to slur a clean website. This one. Libelous and defamatory (both actionable) labels are firmly placed upon me and my reputation. Obviously, no effort has been made to substantiate claims, which are totally untrue. Examination of the content reveals this almost instantaneously. It would take a thorough search to still discover that there is NOTHING that can be construed as explicit or disturbing.
Informative - YES
Thought Provoking - YES
Interesting - MAYBE
Explicit - NO
Disturbing - NO
All content is safe
Thought Provoking - YES
Interesting - MAYBE
Explicit - NO
Disturbing - NO
All content is safe
Opinions are very subjective. My conclusions are derived through reasoned argument and any 'fact' is supported by an original or independent source where possible. I do not read from somebody else's script, but write my own. This is the nature of a blog.
It is not in my remit to knowingly cause offence,
simply provide an alternative point of view.
Everyone is entitled to his own opinion, but not to his own facts
It has never been my intention to be negative, just challenging. A great deal of the subject content (especially government - DA) demands this challenge. To examine issues - as I see it. It's very personal. Very subjective.
- I read from my own script and NOT some other. I think for myself. My opinions are my own and I accept full responsibility for them.
The Philosophical Journal contains ideas that spontaneously occur to me
A Science Journal deals with factual entries
A Science Journal deals with factual entries
- Comment Philosophical Science (Journals)
It should be noted that although many of the Comment entries are of a political nature, any view described is personal. I attempt to highlight what I believe may be a ''hidden agenda' and areas that adversely affect the majority of UQ (aka UK) Ltd citizens. This constitutes the attempted control of the population within this country and is becoming more and more apparent. Much less subtle. Such control has become patently obvious and what bothers me is that we are walking into a potential nightmare with eyes wide shut.
The Pyramid
The psychological exploitation of the introvert/extrovert (Susan Cain) is crude, but unfortunately quite effective.
- The removal of UQ (aka UK) Ltd when referencing the UK was in preparation of better times (May-June 2010), but sadly and predictably, affairs have declined.
- The term may be reintroduced as appropriate.
(Original)
Comment Philosophical Science
The original postings date from April 2005 to November 2006. Currently, dates are up to May 2024. The reason for separating articles is that over 360 entries had been made and different types of postings were progressively becoming confused. To this end there are now three new sources each with an index to simplify finding a particular topic.
posted by Louis Brothnias @ 12:31 AM
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