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Thimerosal neurotoxicity and protection with N-Acetylcysteine supplementation
http://www.healthsentinel.com/news.p..._item&id=3D511
Roman Bystrianyk, "Thimerosal neurotoxicity and protection with N-Acetylcysteine supplementation", Health Sentinel, January 3, 2005, In the 1930s, Eli Lily developed Thimerosal as a preservative and it was widely used in vaccines. Until the removal of Thimerosal, which contains 49.9% ethyl mercury by weight, from most pediatric vaccines in 2001, the source of the largest human exposure to mercury in the US was in children under 18 months of age undergoing routine childhood immunization schedules. Before 2001, a child may have received a cumulative dose of over 200 =B5g/kg (micrograms per kilogram) in the first 18 months of life. Although Thimerosal has been removed from most childhood vaccines, it is still present in the flu vaccine, which is given to pregnant women, the elderly, and children. Also, many vaccines given to children in developing countries still contain Thimerosal. In the 2005 issue of NeuroToxicology, the authors of a study examine the toxicity of Thimerosal within the body including neurons. They examine the neurotoxic mechanisms, how the body detoxifies mercury, and the use of N-Acetylcysteine, or NAC for short, in facilitating the detoxification pathway within the body. Glutathione, a tripeptide composed of cysteine, glutamate, and glycine, is manufactured in the liver and also in the brain. Normally, the concentrations of glutathione in the cells are quite high providing for detoxification of a variety of heavy metals including mercury. However, when this essential antioxidant is depleted the excess mercury can bind to internal cellular proteins leading to toxic damage. Studies have shown that, "low micromolar concentrations of Thimerosal induced DNA strand breaks, caspase-3 activation, membrane damage and cell death." Although the brain can produce glutathione, it can only manufacture this from its immediate precursor cysteine. The liver, on the other hand, is able through a long series of biochemical steps to create glutathione from methionine. Methionine is an essential amino acid that supplies the body with sulfur and methyl groups. The liver uses a number of enzyme systems along with various B vitamins to produce glutathione. The liver then exports the glutathione to the blood that then is broken down to cystine. Cystine crosses the blood-brain barrier to be used by the brain to make glutathione. Thus, the brain is reliant on the liver to manufacture chemicals to keep it free from toxins. The brain contains neurons and other cells called astrocytes. Astrocytes use the cystine that crosses the blood-brain barrier to make glutathione. The astrocytes then export the glutathione to the space between the cells where it is broken down to cysteine. The neurons take up the cysteine and manufacture glutathione. This complex series of biochemical events is what is necessary to keep the brain free from heavy metal damage. The authors first examined the level of Thimerosal that would cause toxic damage to cells. They found that the higher the concentration of Thimerosal the greater the number of cells that were killed although the nerve cell response occurred with only a 3 hour exposure, whereas the other cell line required a 48 hour exposure demonstrating that nerve cells are more sensitive to Thimerosal toxicity. "In both cell lines, a progressive increase in cytotoxicity (decrease in viability) was observed when Thimerosal dose was progressively doubled from 2.5 =B5mol/L [micromoles per liter] to 5, 10, and 20 =B5mol/L. Viability was reduced more than 50% in both cell lines with exposure to 10 =B5mol/L Thimerosal and less than 10% of cells survived a dose of 20 =B5mol/L." The authors then pretreated cells with NAC before adding a dose of 15 =B5mol/L Thimerosal. They found that, "Thimerosal alone induced more than a 6-fold decrease in viability", and that NAC, "provided significant protection against cell death". The authors note, "Thimerosal induces oxidative stress and apoptosis by activating mitochondrial cell death pathways. A subsequent study using cultured human neuron and fibroblast cell lines similarly showed that low micromolar concentrations of Thimerosal induced DNA strand breaks, caspase-3 activation, membrane damage and cell death." The authors conclude that, "numerous clinical studies have demonstrated the efficacy of NAC in increasing intracellular glutathione levels and reducing oxidative stress in humans. Since cytotoxicity with both ethyl- and methyl- mercury have been shown to be mediated by glutathione depletion, dietary supplements that increase intracellular glutathione could be envisioned as an effective intervention to reduce previous or anticipated exposure to mercury. This approach would be especially valuable in the elderly and in pregnant women receiving Rho D immunoglobulin shots, and individuals who regularly consume mercury-containing fish." SOURCE: NeuroToxicology, Vol. 26, 2005, pp. 1-8 |
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Roman Bystrianyk wrote: http://www.healthsentinel.com/news.p..._item&id=3D511 Roman Bystrianyk, "Thimerosal neurotoxicity and protection with N-Acetylcysteine supplementation", Health Sentinel, January 3, 2005, In the 1930s, Eli Lily developed Thimerosal as a preservative and it was widely used in vaccines. Until the removal of Thimerosal, which contains 49.9% ethyl mercury by weight, from most pediatric vaccines in 2001, the source of the largest human exposure to mercury in the US was in children under 18 months of age undergoing routine childhood immunization schedules. Before 2001, a child may have received a cumulative dose of over 200 =B5g/kg (micrograms per kilogram) in the first 18 months of life. Although Thimerosal has been removed from most childhood vaccines, it is still present in the flu vaccine, which is given to pregnant women, the elderly, and children. Also, many vaccines given to children in developing countries still contain Thimerosal. In the 2005 issue of NeuroToxicology, the authors of a study examine the toxicity of Thimerosal within the body including neurons. They examine the neurotoxic mechanisms, how the body detoxifies mercury, and the use of N-Acetylcysteine, or NAC for short, in facilitating the detoxification pathway within the body. Glutathione, a tripeptide composed of cysteine, glutamate, and glycine, is manufactured in the liver and also in the brain. Normally, the concentrations of glutathione in the cells are quite high providing for detoxification of a variety of heavy metals including mercury. However, when this essential antioxidant is depleted the excess mercury can bind to internal cellular proteins leading to toxic damage. Studies have shown that, "low micromolar concentrations of Thimerosal induced DNA strand breaks, caspase-3 activation, membrane damage and cell death." Although the brain can produce glutathione, it can only manufacture this from its immediate precursor cysteine. The liver, on the other hand, is able through a long series of biochemical steps to create glutathione from methionine. Methionine is an essential amino acid that supplies the body with sulfur and methyl groups. The liver uses a number of enzyme systems along with various B vitamins to produce glutathione. The liver then exports the glutathione to the blood that then is broken down to cystine. Cystine crosses the blood-brain barrier to be used by the brain to make glutathione. Thus, the brain is reliant on the liver to manufacture chemicals to keep it free from toxins. The brain contains neurons and other cells called astrocytes. Astrocytes use the cystine that crosses the blood-brain barrier to make glutathione. The astrocytes then export the glutathione to the space between the cells where it is broken down to cysteine. The neurons take up the cysteine and manufacture glutathione. This complex series of biochemical events is what is necessary to keep the brain free from heavy metal damage. The authors first examined the level of Thimerosal that would cause toxic damage to cells. They found that the higher the concentration of Thimerosal the greater the number of cells that were killed although the nerve cell response occurred with only a 3 hour exposure, whereas the other cell line required a 48 hour exposure demonstrating that nerve cells are more sensitive to Thimerosal toxicity. "In both cell lines, a progressive increase in cytotoxicity (decrease in viability) was observed when Thimerosal dose was progressively doubled from 2.5 =B5mol/L [micromoles per liter] to 5, 10, and 20 =B5mol/L. Viability was reduced more than 50% in both cell lines with exposure to 10 =B5mol/L Thimerosal and less than 10% of cells survived a dose of 20 =B5mol/L." The authors then pretreated cells with NAC before adding a dose of 15 =B5mol/L Thimerosal. They found that, "Thimerosal alone induced more than a 6-fold decrease in viability", and that NAC, "provided significant protection against cell death". The authors note, "Thimerosal induces oxidative stress and apoptosis by activating mitochondrial cell death pathways. A subsequent study using cultured human neuron and fibroblast cell lines similarly showed that low micromolar concentrations of Thimerosal induced DNA strand breaks, caspase-3 activation, membrane damage and cell death." The authors conclude that, "numerous clinical studies have demonstrated the efficacy of NAC in increasing intracellular glutathione levels and reducing oxidative stress in humans. Since cytotoxicity with both ethyl- and methyl- mercury have been shown to be mediated by glutathione depletion, dietary supplements that increase intracellular glutathione could be envisioned as an effective intervention to reduce previous or anticipated exposure to mercury. This approach would be especially valuable in the elderly and in pregnant women receiving Rho D immunoglobulin shots, and individuals who regularly consume mercury-containing fish." SOURCE: NeuroToxicology, Vol. 26, 2005, pp. 1-8 |
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A press release about Mercury in Thimerosal from the National Vaccine
Information Center in July of 1999 press pointed out that, "The cumulative effects of ingesting mercury can cause brain damage." During this same month, the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) alerted the public about the possible health effects associated with thimerosal-containing vaccines. These health-related organizations strongly recommended that thimerosal be removed from vaccines as soon as possible. Under the directive of the FDA Modernization Act of 1997, the Food and Drug Administration also determined that infants who received several thimerosal-containing vaccines may be receiving mercury exposure over and above the recommended federal guidelines. The link between thimerosal and autism and other learning disabilities has continued to be argued for decades. Thimerosal is 49.6% ethylmercury and was widely used since the 1940s in over the counter drugs. After being banned in 1998 from over the counter drugs, thimerosal is still found in some vaccines. Mercury is the second most toxic substance known to man behind uranium. N-Acetylcysteine or NAC is mentioned in your artiicle which states how helpful it is in facilitating the detoxification pathway within the body. NAC is produced in living organisms from the amino acid cysteine. Thus, NAC is a natural sulfur-containing amino acid derivative found naturally in foods and is a powerful antioxidant. These dual properties help repair oxidative damage in the body. Being a powerful anti-oxidant and cell detoxification co-factor, NAC works to eliminate your body of free radicals and heavy metals. In short, it improves your cellular health tremendously and is currently the dietary supplement of choice for building up cysteine or conserving the body's store of Glutathione, This is very crucial for the body's life functions, as NAC helps the body neutralize toxins, heavy metals, such as mercury from dental amalgam fillings, cadmium and lead from paint and cigarette smoke. The Sulfhydryl balance has also been linked to enhance resistance to viral infections. Taken regularly over a period of time, NAC will remove many toxic heavy metals from the body. |
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In article . com,
wrote: A press release about Mercury in Thimerosal from the National Vaccine Information Center in July of 1999 press pointed out that, "The cumulative effects of ingesting mercury can cause brain damage." During this same month, the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) alerted the public about the possible health effects associated with thimerosal-containing vaccines. These health-related organizations strongly recommended that thimerosal be removed from vaccines as soon as possible. This has now been done. To the surprise of nobody other than the anti-mercury fanatics, autism has not become a thing of the past. Under thedirective of the FDA Modernization Act of 1997, the Food and Drug Administration also determined that infants who received several thimerosal-containing vaccines may be receiving mercury exposure over and above the recommended federal guidelines. Well, not really. Also, it does appear that the body clears ethylmercury very quickly, so the exposure is short. The link between thimerosal and autism and other learning disabilities has continued to be argued for decades. Because the anti-thimerosal people don't want to give up on it. Thimerosal is 49.6% ethylmercury and was widely used since the 1940s in over the counter drugs. After being banned in 1998 from over the counter drugs, thimerosal is still found in some vaccines. Though flu vaccine is the only such vaccine that is also recommended for children. Mercury is the second most toxic substance known to man behind uranium. No, it's not. Not even close. Nor is uranium the most toxic substance known. silly blurb about NAC snipped -- though it may be good for people taking lithium carbonate, to help reduce liver toxicity -- David Wright :: alphabeta at prodigy.net These are my opinions only, but they're almost always correct. "If I have not seen as far as others, it is because giants were standing on my shoulders." (Hal Abelson, MIT) |
#5
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wrote in message ups.com... Thimerosal is 49.6% ethylmercury Anyone who took a high school chemistry course can see how bogus this claim is. I'll give you a hint: The 49.6% number is the percentage that the mercury atom in thimerosal is as part of the molecular weight. Now, explain why this percentage is significant (other than being a large percentage). |
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"Peter Bowditch" wrote in message Note also that the statement "Thimerosal is 49.6% ethylmercury" is contrary to the teachings of His Holiness Professor Boyd Haley, who in a personal communication with me said "mercury is 49.59% of the weight of thimerosal". He was talking about elemental mercury at the time, not the chemical compound ethylmercury. Unless, of course, the writer was referring to a claim made elsewhere by Dr Haley where he contradicted himself. it is sad you pharma morons are reduced to claiming thimerosol is somehow safe by barfing about the mercury content and toxicity. http://www.nomercury.org/Is_Mercury_Dangerous.htm Specific Toxicities of Thimerosal After years of medical practice, many physicians and other health professionals were indeed shocked to learn that most vaccines used over the years actually contained up to 25 micrograms of ethyl mercury. Ethyl mercury, despite what some have professed, has a very similar toxicological profile as the dreaded methyl mercury found in water, fish, and soil. As a physician, I was recently shocked by the comments of a neighboring state's chief epidemiologist who informed a state legislator (who was considering a "ban Thimerosal" bill) that ethyl mercury, compared to methyl mercury, was safe because ethyl alcohol was safe and methyl alcohol wasn't. Of course, any high school chemistry student knows better. Would this same epidemiologist take an injection of ethyl plutonium? In fact, there have been many peer-reviewed studies that addressed Thimerosal specifically. Here are just a few highlights: The comparative toxicology of ethyl- and methyl mercury by Magos, Brown, Sparrow, Bailey, et al published in the Archives of Toxicology (1985) 57: 260-267., has stated: "There was little difference in the neurotoxicities of methylmercury and ethylmercury when effects on the dorsal root ganglia or coordination disorders were compared." |
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"john" wrote in message ... "Peter Bowditch" wrote in message Note also that the statement "Thimerosal is 49.6% ethylmercury" is contrary to the teachings of His Holiness Professor Boyd Haley, who in a personal communication with me said "mercury is 49.59% of the weight of thimerosal". He was talking about elemental mercury at the time, not the chemical compound ethylmercury. Unless, of course, the writer was referring to a claim made elsewhere by Dr Haley where he contradicted himself. it is sad you pharma morons are reduced to claiming thimerosol is somehow safe by barfing about the mercury content and toxicity. It is sad that you anti-vac murderers of children are reduced to claiming that thimerosal is somehow unsafe by posting your cleanses about the mercury content to imply toxicity. |
#9
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In article ,
john wrote: "Peter Bowditch" wrote in message Note also that the statement "Thimerosal is 49.6% ethylmercury" is contrary to the teachings of His Holiness Professor Boyd Haley, who in a personal communication with me said "mercury is 49.59% of the weight of thimerosal". He was talking about elemental mercury at the time, not the chemical compound ethylmercury. Unless, of course, the writer was referring to a claim made elsewhere by Dr Haley where he contradicted himself. it is sad you pharma morons are reduced to claiming thimerosol is somehow safe by barfing about the mercury content and toxicity. http://www.nomercury.org/Is_Mercury_Dangerous.htm Specific Toxicities of Thimerosal After years of medical practice, many physicians and other health professionals were indeed shocked to learn that most vaccines used over the years actually contained up to 25 micrograms of ethyl mercury. Ethyl mercury, despite what some have professed, has a very similar toxicological profile as the dreaded methyl mercury found in water, fish, and soil. As a physician, I was recently shocked by the comments of a neighboring state's chief epidemiologist who informed a state legislator (who was considering a "ban Thimerosal" bill) that ethyl mercury, compared to methyl mercury, was safe because ethyl alcohol was safe and methyl alcohol wasn't. Of course, any high school chemistry student knows better. Would this same epidemiologist take an injection of ethyl plutonium? In fact, there have been many peer-reviewed studies that addressed Thimerosal specifically. Here are just a few highlights: The comparative toxicology of ethyl- and methyl mercury by Magos, Brown, Sparrow, Bailey, et al published in the Archives of Toxicology (1985) 57: 260-267., has stated: "There was little difference in the neurotoxicities of methylmercury and ethylmercury when effects on the dorsal root ganglia or coordination disorders were compared." As a person who can read and then comprehend what he reads, I was not at all shocked that Scudamore would screw up again and post this nearly meaningless study as if it were some sort of evidence against the use of thimerosal in vaccines. Here's one good quote from the abstract: Based on both criteria, an equimolar dose of ethylmercury was less neurotoxic than methylmercury So we're off to a fine start. But more importantly, and this is not at all surprising when you consider what a scientific illiterate Scudamore is, the usefulness of this study (for applicability to vaccines) is near zero. Here's why: 1) The study was done in rats, not humans. 2) The rats were being administered 8.0 or 9.6 *milligrams* (per kilogram of body weight) of mercury compounds five times per day. (The abstract does not say how long this went on.) 3) The compound administered was ethylmercuric chloride or methylmercuric chloride. But it's point 2 in the list above that really makes the difference. If you translate the dosage to, say, a 5 kg (11 lb) infant, that infant would be getting at least 40 milligrams of mercury PER DAY. In order to get that much from a thimerosal-containing vaccine, the infant would have to receive 1600 vaccine injections PER DAY. (Well, that's approximate, since the rats weren't getting that sort of injection, but close enough.) The fact that the rats were taking some nerve damage, but not just dropping dead on the spot, shows that the mercury is less toxic than I would have expected. What's more important is that other studies have shown that mercury in vaccines is not the horror that the anti-vac/angy-Hg loons attempt to portray. For example, Pichichero et al, "Mercury concentrations and metabolism in infants receiving vaccines containing thiomersal: a descriptive study." (Lancet Nov 30 2002) has this: FINDINGS: Mean mercury doses in infants exposed to thiomersal were 45.6 microg (range 37.5-62.5) for 2-month-olds and 111.3 microg (range 87.5-175.0) for 6-month-olds. Blood mercury in thiomersal-exposed 2-month-olds ranged from less than 3.75 to 20.55 nmol/L (parts per billion); in 6-month-olds all values were lower than 7.50 nmol/L. Only one of 15 blood samples from controls contained quantifiable mercury. Concentrations of mercury were low in urine after vaccination but were high in stools of thiomersal-exposed 2-month-olds (mean 82 ng/g dry weight) and in 6-month-olds (mean 58 ng/g dry weight). Estimated blood half-life of ethylmercury was 7 days (95% CI 4-10 days). INTERPRETATION: Administration of vaccines containing thiomersal does not seem to raise blood concentrations of mercury above safe values in infants. Ethylmercury seems to be eliminated from blood rapidly via the stools after parenteral administration of thiomersal in vaccines. Meanwhile, here's a 2003 J. Appl Toxicol. paper by Magos: The decomposition rate of organomercurials and the potency of the blood-brain barrier increase with the size of the organic radical. Thus methylmercury damages the brain more than thimerosal does, and when intake limits set for methylmercury are applied to thimerosal the safety margin is increased even if the clearances were the same. However, the clearance half-time of ethylmercury in adults is about one-third of the 50 days' clearance half-time of methylmercury given for 60 kg body weight. Moreover, because metabolic rates (e.g. basal metabolism, daily loss of mercury in per cent of body burden) in different weight groups are related to the fractional power of body weight (rule of allometry), mercury clears from the infant body faster than from the adult body. Blood mercury concentrations observed after vaccination showed agreement with allometrically extrapolated concentrations. Copyright 2003 John Wiley & Sons, Ltd. -- David Wright :: alphabeta at prodigy.net These are my opinions only, but they're almost always correct. "If I have not seen as far as others, it is because giants were standing on my shoulders." (Hal Abelson, MIT) |
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Pregnant women were "Injected" with mercury via Rhogam or the flu vaccine
with 25-35 mcg of Mercury. The EPA limit for "INGESTING" mercury is 6 mcg for a 132 lb person. There is no safe limit on INJECTING mercury into a pregnant woman, Mercury crosses over the placenta and targets the brain of a fetus, the fetus has no blood brain barrier to protect itself from the mercury. Mercury is a Neurotoxin....What do you think happens to a fetal brain after mercury makes its way there??? Methyl-mercury, usually from contaminated food, is very dangerous to pregnant women. Methyl-mercury causes profound mental retardation, cerebral palsy, seizures, spasticity, tremors, and incoordination, along with eye and hearing damage in the unborn baby as a result of the mother's exposure. Organic mercury passes into the breast milk as well. The effect of thimerosal, an organomercurial preservative in vaccines, on cerebellar neurons dissociated from 2-week-old rats was compared with those of methylmercury using a flow cytometer with appropriate fluorescent dyes. Thimerosal and methylmercury at concentrations ranging from 0.3 to 10 microM increased the intracellular concentration of Ca2+ ([Ca2+]i) in a concentration- dependent manner. The potency of 10 microM thimerosal to increase the [Ca2+]i was less than that of 10 microM methylmercury. Their effects on the [Ca2+]i were greatly attenuated, but not completely suppressed, under external Ca(2+)-free condition, suggesting a possibility that both agents increase membrane Ca2+ permeability and release Ca2+ from intracellular calcium stores. The effect of 10 microM thimerosal was not affected by simultaneous application of 30 microM L-cysteine whereas that of 10 microM methylmercury was significantly suppressed. The potency of thimerosal was similar to that of methylmercury in the presence of L-cysteine. Both agents at 1 microM or more similarly decreased the cellular content of glutathione in a concentration-dependent manner, suggesting an increase in oxidative stress. Results indicate that thimerosal exerts some cytotoxic actions on cerebellar granule neurons dissociated from 2-week-old rats and its potency is almost similar to that of methylmercury. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi? cmd=Retrieve&db=PubMed&list_uids=14698570&dopt=Abs tract It should be noted that this research study compared equal doses of methylmercury and thimerosal. However, thimerosal is only 1/2 mercury (ethylmercury), so the authors should have compared 1/2 dose thimerosal with 1 dose methylmercury. The conclusion would then be that ethylmercury is equally potent to methylmercury in increasing Ca2++. The study also says that unlike methylmercury (which is usually bound to cysteine in a cell) thimerosal's potency is unaffected by presence of L-cysteine in the neuron, so under in vivo conditions the effects of ethylmercury are likely greater (by a factor or 2) than methyl. Finally, the study shows that thimerosal is more potent than methyl in decreasing glutathione levels in the cell, which is what other researchers have/are finding as well. Effects of Mercury Administered during Pregnancy A reader named "Donna" contacted Midwifery Today E-News with an informal study she conducted of mothers who were "injected" with mercury while pregnant. She started with her own story: http://www.midwiferytoday.com/enews/enews0624.asp? Donna (mother to a profoundly MERCURY poisoned child) |
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