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BSE Test

bse-tester

Well-known member
TimH wrote:

Are you prepared to state, Ron Arnold, that "bse-infectivity" or "prions" or "PrPsc" is definitely found in the muscle tissues of cattle? If so,I invite you to go ahead and say so in your very next post. Up until now you have only suggested that it may be possible.

Darn right I am!!

Like I said Tim, we find PrPsc in blood, in nerve fibrils, in tongue, in liver, in the spleen, in the eyes, in spinal tissue & fluids, in the kidneys, in muscle tissue, in mucous membrane and in the intestinal walls as well as urine - to name but a few locales, besides the brain and other listed SRM's.
 

TimH

Well-known member
bse-tester said:
TimH wrote:

Are you prepared to state, Ron Arnold, that "bse-infectivity" or "prions" or "PrPsc" is definitely found in the muscle tissues of cattle? If so,I invite you to go ahead and say so in your very next post. Up until now you have only suggested that it may be possible.

Darn right I am!!

Like I said Tim, we find PrPsc in blood, in nerve fibrils, in tongue, in liver, in the spleen, in the eyes, in spinal tissue & fluids, in the kidneys, in muscle tissue, in mucous membrane and in the intestinal walls as well as urine - to name but a few locales, besides the brain and other listed SRM's.

flounder wrote-

"....the srm regulations will have to change when they document BSE in muscle tissue, so why document it.
AS with blood, where they once thought it too be free of TSE infection, but was wrong there as well, give em time, and more sensitive testing and they will find BSE in muscle tissue of cattle,..."

I'm pretty sure that flounder, who is as well read on BSE as anyone, just admitted that PrPsc has NEVER been found in muscle tissues of cattle.
You can read, can't you Ron? Wishing don't make it so.
It's pretty simple, Slick. Find another way to create demand for your te$t.
.
 

bse-tester

Well-known member
Flounder wrote:

Page 9 of 17 Cattle infected with bovine spongiform encephalopathy (BSE) appear to be a reservoir for transmission of variant Creutzfeldt-Jakob disease (vCJD) to humans. Although just over 100 people have developed clinical vCJD, millions have probably been exposed to the infectivity by consumption of BSE-infected beef. It is currently not known whether some of these individuals will develop disease themselves or act as asymptomatic carriers of infectivity which might infect others in the future.

TimH wrote:

I'm pretty sure that flounder, who is as well read on BSE as anyone, just admitted that PrPsc has NEVER been found in muscle tissues of cattle.
You can read, can't you Ron? Wishing don't make it so.
It's pretty simple, Slick. Find another way to create demand for your te$t.

I guess it is true Flounder - this guy has no clue at all when it comes to prion disease and it appears to be plain as day that he is the one who not only cannot interpret plain English, but has a real hard time reading it also.

Flounder quoted:

Muscle prion titers at the high end of the range produced the fastest incubation times that were ~30% longer than the incubation times of prions from the CNS of the same animal. Since all mice in each inoculation group developed disease, prion titers in muscle samples producing the longest incubation times were higher than the end point of the bioassay, defined as the infectious dose at which half the inoculated mice develop disease. Studies are in progress to accurately assess prion titers.

While the risk of exposure to CWD infectivity following consumption of
prions in muscle is mitigated by relatively inefficient prion transmission
via the oral route (, these results show that semitendinosus/semimembranosus muscle, which is likely to
be consumed by humans, is a significant source of prion infectivity. Humans consuming or handling meat from CWD-infected deer are therefore at risk to prion exposure.

I think that puts and end to this battery of ridiculous questions from the Manitoba boy!! But then, we both know he will not accept anything from me or from you Flounder so we are back to the trees and the forest routine with him. I am putting him on ignore!! You can treat him as you wish but for me, I have had enough of him.

One last thing Flounder - our test, which I am not trying to sell by the way, only have validated, is an extremely sensitive detection protocol for PrPsc. It is so sensitive that it will detect the presence of prion disease in as little as 1ml of urine. In other words, in the words of the United States National Prion Surveillance Center, "....if the disease is present, the Biotec Global Urine Test will find it."

The problem with the tests that have been cited in Flounder's posting, is that they were perhaps not as sensitive and therefore could not detect the prion infection. That is actually mentioned. Plus, our antibody is not monoclonal. It is far superior and the use of the Western Blot process nails it each and every time.
 

Kathy

Well-known member
Kathy wrote:

The lysosome's enzymes will digest these malformed proteins. In the case of protease-resistant prions, the enzyme may only break apart some of this protein, if any.

If the lysosome is unable to digest these malformed proteins, eventually the lysosome will fill with them and explode, releaseing them and the rest of its contents into the living cell. If enough lysosomes within the cell burst and release their contents, including acidic enzymes, the cell will eventually die.

bse-tester wrote:

This is only if the protein is absorbed into the lysosme. PrPsc has a tendency to be virtually invisible to the predators within the body. This is what makes this incidious little critter so darn interesting. It literally moves through the entire animal or human undeted by the very systems desgned to combat contaminant bodies.

Your analogy/description is really good and the end result of the cell death is the vacuoles that are found in the brain. The classic "Swiss Cheese effect." The areas of dead brain tissue is the result of the cell dying and the replication of the PrPsc within it.

Kathy wrote:

Since I am more prone to believe that the PrPsc is caused by a screw-up in the initial manufacturing process, and not a post-translational change, the buildup of Prpsc in the brain may not be the result of PrPsc travelling via the blood stream to the brain, crossing the blood brain barrier. It is very plausible the causative agent(s) are transported via metallo-protein transporters like MTF, into the brain, for the manufacturing process.

Too much manganese, for example, could upset the delicate balance; providing the DNA manufacturing process with no options but to put the inappropriate metal into a copper local. Then this newly manufactured protein sequence renders the protein useless (garbage), eventually it builds up (once the lysosomes and other garbage or immune mechanisms give up their fight and stop doing their job).

bse-tester wrote:

There is evidence to support the hypothesis that the normal PrP present in the brain - the PrP that provides a link, just like a fuse in an electrical circuit, when subjected to metal depletion or an over abundance of metals, reacts in such a way that the neurons that travel through the protein wherein they are allowed to pass to their target - a brain function that tells the host to move their little finger perhaps - are actually blocked by a protein that is not as effectively functional due to the metal depletion or metal overload. One school of thought is that this difference in the metal levels, copper in particular, is responsible for the misfolded isoform and subsequent change to the physical structure of the protein into PrPsc from PrP. The slightest drop or increase in metal content can have a profound affect on the conductivity of the neuron pathway. When the trigger is fired and the neuron is on its way to deliver its message, sotospeak, if the pathway is corrupted, then the signals are also corrupted, especially in the case of slight metal changes. In the case of high metal changes in the system, the pathways are completely cooked due to the malformation of the prion and therefore we see the clinical sysmptoms such as ataxia - shaking - and memory loss. Afterall, if the brain is not get the right or no signal at all, then it slowly ceases to function.

Keep at it Kathy.

And now some new information on this subject (supplementary info to a 2004 report):

Folia Neuropathol. 2004;42 Suppl B:153-60

Ultrastructural alterations in the optic nerve in transmissible spongiform encephalopathies or prion diseases--a review.

Walis A, Liberski PP, Brown P.

Department of Neurology, Mikolaj Kopernik memorial Regional Multidisciplinary Hospital, Lodz, Poland.

The involvement of the visual system is well recognised in TSEs. The present review summarises the ultrastructural changes in the optic nerves in experimental infections of laboratory rodents with the agents of two human TSEs (CJD and GSS) and with two isolates of the scrapie agent. Vacuoles of myelinated fibres were found within myelin sheaths and themselves contained secondary vacuoles (vacuoles within other vacuoles) and curled membrane fragments not unlike the vacuoles in cerebral grey matter (see also: Spongiform change--an electron microscopic view; this issue). The myelin sheath had split either at the major dense line or at the intraperiod line. In addition, axons contained vacuoles within the axoplasm, corresponding to the typical spongiform vacuoles of grey matter. Vacuolation of myelinated fibres was accompanied by an exuberant cellular reaction consisting of macrophages containing numerous mitochondria, abundant rough endoplasmic reticulum and secondary lysosomes filled with digested myelin debris, electron-dense material and sometimes entire myelin-bounded vacuoles. Within macrophages myelin fragments undergoing active digestion were often seen, together with lyre-like bodies and paracrystalline inclusions. Astrocytes and their processes were prominent and glial filaments and many mitochondria were readily detected. Proliferation of the inner mesaxons was also seen. Cross-sectional profiles of many myelinated fibres contained membranous organelles continuous with the inner lamellae of the oligodendroglial cells. The inner mesaxon proliferations formed whorls and loops. In some axons proliferation was so severe that the mesaxonal loops filled the whole cross-section of the axon. Occasionally there was intrusion of the membranous tongue of the inner mesaxon into the axoplasm. Dystrophic neurites were relatively numerous. In GSS-infected animals some axons underwent demyelination with stripping of the myelin lamellae, while still others underwent vesicular myelin degeneration. It is of special note that in the cytoplasm of several cells as well as the axoplasm numerous autophagic vacuoles were seen.
PMID: 16903149

So what do you think bse-tester?

Have you seen the University of Calgary video which shows (in a time lapsed video) mercury ions caused the demyelination of the nerve sheath (snail brain cell). It is amazing video! The nerve extensions are seen growing and active; then after mercury ions are added, they die back to the cell body.

http://commons.ucalgary.ca/mercury/
 

bse-tester

Well-known member
Kathy, there is little doubt that the metalic infusion of mercury is a brain-killer! The video was perfect for those who have no idea how it happens. The video showed in clear detail how mercury literally acts like a fibril/interferon and shows how the fibril is left naked and dying back. The entire act is clear. The mercury destroys that ability of the brain to provide natural connections and not only runs interference on this occurrence, but lays waste to the ability of the brain to recover from mercury infusion. Good video Kathy.

One thought though - we should be considering the fact that more than one complete generation have been subjected to mercury-based amalgam in their teeth!!! Is it any wonder that we are seeing a higher rate of Alzheimer's Disease lately than we did decades ago??
 

TimH

Well-known member
reader (the Second) said:
bse-tester said:
TimH wrote:

Are you prepared to state, Ron Arnold, that "bse-infectivity" or "prions" or "PrPsc" is definitely found in the muscle tissues of cattle? If so,I invite you to go ahead and say so in your very next post. Up until now you have only suggested that it may be possible.

Darn right I am!!

Like I said Tim, we find PrPsc in blood, in nerve fibrils, in tongue, in liver, in the spleen, in the eyes, in spinal tissue & fluids, in the kidneys, in muscle tissue, in mucous membrane and in the intestinal walls as well as urine - to name but a few locales, besides the brain and other listed SRM's.

One of the international experts on prions in blood put it this way -- there's prions in blood, no doubt about it and that blood runs through the body so why would you think there are no prions in muscle??

Apparently more so with BSE and with vCJD -- both introduced externally through the gut and therefore infect more of the body than classic CJD.

In experiments with mice who are intercerebrally innoculated, by the time they are close to death, they are shedding prions in their feces and urine. Which must be pretty scary for researchers and what they have to have a Bio Hazzard Level 2 (?3) facility to do TSE research.

Blah, blah, blah...... And the study in which prions have been found in the MUSCLE TISSUE OF NON-EXPERIMENTALLY INFECTED CATTLE IS.........WHERE????? Show me.
Way easier to suggest it than to prove it ,right Rhetoric(the second) ??
 

flounder

Well-known member
CJD WATCH MESSAGE BOARD
TSS
SEAC 2006 METHODS TO EVALUATE NEW SURGICAL INSTRUMENT
Tue Aug 22, 2006 15:35
68.238.101.250


Analysis of surgical and dental instruments had provided data on the variation in amounts of protein residues on instruments before and after cleaning. Unpublished research suggested the scrapie agent is 1000 to 10 000 fold more infectious when dried onto a metal surface than when in wet form.


snip...


ITEM 7 - METHODS TO EVALUATE NEW SURGICAL INSTRUMENT DECONTAMINATION TECHNOLOGIES (SEAC 93/5)


34. The SEAC Chair explained that the Engineering and Science Advisory Committee into the decontamination of surgical instruments including prion removal (ESAC-Pr) is considering the evaluation and implementation of new decontamination technologies to reduce the risk of transmission of TSEs via surgical instruments. SEAC has been asked by ESAC-Pr to advise on the principles to consider when developing a strategy to evaluate new decontamination technologies, particularly on the most appropriate TSE agents and experimental systems.


35. Dr John Stephenson (DH) provided an overview of DH policy and research on TSE decontamination of surgical instruments. TSE agents are resistant to standard decontamination practices used in sterile service departments (SSDs) and contaminated surgical instruments have been shown to transmit prion disease. A key priority for DH is the provision of clean and sterile reuseable surgical instruments. DH research covered three areas:


. estimating the risk of vCJD transmission via surgery by determining the thermal resistance of the BSE/vCJD agent, the protein load on surgical instruments leaving SSDs, the level of infectivity in human tissue and the prevalence of disease in the UK population. The programme had shown the vCJD agent is as resistant to thermal inactivation as the BSE agent, with autoclaving only reducing vCJD infectivity by two to three logs. A survey of appendix and tonsil tissue had provided estimates of the prevalence of vCJD infection. Infectivity studies on tissues from vCJD cases had allowed a categorisation of human tissues. Analysis of surgical and dental instruments had provided data on the variation in amounts of protein residues on instruments before and after cleaning. Unpublished research suggested the scrapie agent is 1000 to 10 000 fold more infectious when dried onto a metal surface than when in wet form.


. development of methods to rapidly detect and quantify low levels of contamination on surgical instruments before processing to identify instruments that may need special treatment, and after processing to ensure the instruments could be used. Research had shown that the standard ninhydrin test for protein was of little value. A number of other methods including high sensitivity immunochemical, fluorometric, microscopic and magnetic acoustic resonance

13 © SEAC 2006


detection methods had been developed with detection limits in the 10-18 mole to 10-15 mole of protein/mm2 range. Infectivity assays using material bound to stainless steel wires and spheres had also been developed to validate novel inactivation technologies.


. development of novel cleaning and inactivation methods for instruments. Research suggested that alkali autoclaving at high or low temperatures removed infectivity and did not damage high quality instruments, however this process damaged low quality surgical instruments. Some laboratory detergents removed some, but not all proteins, from surfaces with some specialised commercial detergents particularly efficient. Use of thermostable enzymes in conjunction with detergents removed virtually all detectable protein and infectivity. High energy gas plasmas had been shown to remove detectable organic material from the stainless steel surfaces, cavities and long lumens of instruments. Current research was examining whether instruments could be coated to prevent adsorption of protein onto surfaces. There were promising results from tests on a diamond like surface.


36. Dr Stephenson explained that a number of decontamination products were being commercialised. Therefore, DH had convened ESAC-Pr to consider ways in which these new processes could be formally evaluated and, where appropriate, brought into practice in the National Health Service. ESAC-Pr and the Medicines and Healthcare products Regulatory Agency have recommended that current decontamination guidelines be followed until novel technologies have been formally evaluated. Taking into account advice from SEAC, ESAC-PR will produce generic performance criteria for such technologies. As a result new guidelines will be written by the Advisory Committee on Dangerous Pathogens (ACDP) TSE Working Group and issued by DH.


37. The Chair asked whether the variance in levels of protein contamination on surgical instruments reflected poor decontamination practice in some SSDs. Professor Don Jeffries (Chair of the ACDP TSE Working Group and member of ESAC-Pr) explained that variability in the level of residual protein on instruments was found between high quality SSDs and often variability in the level of residual protein was found between the same instruments. Residues did not correlate with the complexity of instruments. This variability may be due to protein residues drying onto instruments as it is suspected that residual tissue in dry form is harder to remove. The committee agreed it was very

14 © SEAC 2006


important to examine the effect of allowing protein deposits to dry onto surfaces and its subsequent resistance to removal.


38. A member noted that no gold standard system exists that allows complete evaluation of technologies for TSE decontamination. However, based on a review of the published literature on the assessment of decontamination technologies, there are a number of key requirements for an evaluation system. The system should:


. quantify the reduction in the titre of infectivity as a result of the decontamination process. This would allow the effectiveness of a decontamination method to be assessed and compared with other decontamination technologies. It is important that the titration curve to allow quantification is generated using the same experimental system used to test the decontamination treatment. For example, if the decontamination method is tested on a brain homogenate, the titration curve should be generated from dilutions of the same homogenate. If the decontamination method is tested using homogenate bound to stainless steel wires, the titration curve should also be generated from stainless steel wires treated with dilutions of the homogenate. The method of experimental contamination of stainless steel varies widely between published studies with drying of material onto stainless steel used in some studies. This may be a potential source of variability in assessments of decontamination methods since dried material may be more resistant to decontamination than wet material. Consideration should be given to standardisation of experimental contamination of stainless steel.


. not be restricted to the use of hamster adapted scrapie prions as studies show that sporadic CJD and BSE prions appear to be more resistant to decontamination than the hamster scrapie strain. In addition, if it is intended that the decontamination technology be applied to instruments used exclusively on tissues outside the central nervous system (CNS), it is important that the technology be assessed using a TSE strain that has wide distribution, including the lymphoreticular system (LRS). As the most commonly used 263K hamster scrapie strain is poorly lymphotropic, alternative models using TSE agents with tissue distribution including the LRS should be used as well. These include mice with mouse adapted vCJD or BSE and bovinised or humanised mice with BSE or vCJD, respectively. These models would more closely represent the human situation than the hamster scrapie model.

15 © SEAC 2006


. include evaluation by bioassays as they are the most sensitive and relevant assays for evaluating the effectiveness of a decontamination technology to remove or deactivate TSE infectivity.


. include preliminary screening of the effectiveness of a new decontamination technology prior to evaluation by bioassay. Cellular infection assays, although not yet fully developed, would be preferable as preliminary screens compared with biochemical assays. As the relationship between PrPSc and infectivity is not well understood, the relationship between PrPSc and infectivity may vary between TSE strains and PrPSc and infectivity may be affected differently by decontamination treatments, biochemical assays may not accurately predict the effectiveness of decontamination. However, biochemical tests may be useful to determine the mechanism of decontamination or to monitor the effectiveness of a decontamination method once its effectiveness has been established.


39. Dr Stephenson noted that the mechanism of action of new decontamination treatments varies widely and asked whether evaluation systems need to be tailored to the type of decontamination technology or should a suite of systems be used that would be applicable to all types of decontamination technology. Members agreed that use of different systems to evaluate different decontamination treatments would make comparison of their effectiveness very difficult. Therefore, the same, rigorous evaluation system should be applied to all decontamination technologies under evaluation.


40. Members asked whether there was variation in the composition of stainless steel used in surgical instruments and whether this would introduce variation in the binding of prions. Dr Stephenson explained that there is variation in the composition of stainless steel and this affects the resistance of instruments to damage by cleaning processes. It was notable that alterations to the structure of the surface, for example by introducing a diamond-like surface, could modify protein binding. Dr Nigel Tomlinson (DH) noted that no study had compared the binding of proteins, or prion proteins, to the different types of stainless steel used to produce surgical instruments.


41. Professor Jeffries noted that a number of new decontamination products have been, or will soon be, CE marked11 on the basis of

11 CE (Conformité Européene) mark is a declaration by the manufacturer that a product meets all the necessary requirements of the relevant EU legislation.

16 © SEAC 2006


assessments made using systems that may not be relevant to human TSE agents. In evaluating new decontamination technologies, it was also very important to establish that new treatments do not leave residues on instruments that adversely affect patient safety and do not compromise removal of other infectious agents. As some treatments, such as aldehydes, had been shown to increase the resistance of proteins to decontamination, he asked if it was possible for new decontamination treatments to alter the phenotype of TSE agents. Members agreed that, as the nature of TSE agents is not well understood, treatments, which alter protein structure could, potentially, alter their infectious properties. Members considered it essential that the effect of decontamination treatments on TSE infectivity, not just prion or other protein levels, be evaluated. Since the binding of PrPSc to stainless steel was relatively strong, assays to measure the effect of a decontamination treatment on removal of protein may not be a good marker for removal of PrPSc.


42. A member asked if high pressure inactivation of TSE agents had been investigated. Dr Stephenson explained that a research application addressing this had been accepted by a review panel but it would not be funded due to research budget restrictions.


43. A member asked whether evaluation systems should assess the effectiveness of new decontamination technologies to remove dried on material, or would instruments in the future be kept in a wet environment until processed in a SSD. Professor Jeffries noted that experiments to examine the effect of leaving material on instruments to dry for various periods of time should be conducted, however this was precluded by current restrictions on research funding. He noted that guidelines in other countries recommended that instruments be kept wet prior to processing in SSDs. The UK Health and Safety Executive had advised that instruments could be kept wet in transit if appropriate sealed containers were used. Members considered it very important that these relatively simple experiments be carried out as the results could have a major impact on processing of surgical instruments. The committee noted that progress in a number of research areas was limited by the lack of available funds and asked when funds were likely to be released. Dr Stephenson responded that it was presently unclear when further research funds would become available but funding for some areas could be prioritised.


44. A member asked if research on removable surfaces on surgical instruments that would trap TSE contamination had been

17 © SEAC 2006


considered. Dr Stephenson explained that this approach had been considered but no studies had been commissioned.



http://www.seac.gov.uk/minutes/draft93.pdf


PLEASE NOTE!

SINCE spontaneous scrapie or CWD does not occur, then why is it that only BSE and sproadic CJD are capable of spontaneous mutation $$$

confusious is confused again;-) ...TSS




Science 24 September 2004:
Vol. 305. no. 5692, pp. 1918 - 1921
DOI: 10.1126/science.1103581



Perspectives
BIOMEDICINE:


A Fresh Look at BSE


Bruce Chesebro*


Mad cow disease, or bovine spongiform encephalopathy (BSE), is the cattle form of a family of progressive brain diseases. These diseases include scrapie in sheep, Creutzfeldt-Jakob disease (CJD) in humans, and chronic wasting disease (CWD) in deer and elk. They are also known as either "prion diseases" because of the association of a misfolded cellular prion protein in pathogenesis or "transmissible spongiform encephalopathies" (TSEs) because of the spongelike nature of the damaged brain tissue (1).

The recent discovery of two BSE-infected cows, one in Canada and one in the United States, has dramatically increased concern in North America among meat producers and consumers alike over the extent to which BSE poses a threat to humans as well as to domestic and wild animals. The European BSE epidemic of the late-1980s seems to have been initiated a decade earlier in the United Kingdom by changes in the production of meat and bone meal (MBM) from rendered livestock, which led to contamination of MBM with the BSE infectious agent. Furthermore, the fact that UK farmers fed this rendered MBM to younger animals and that this MBM was distributed to many countries may have contributed to the ensuing BSE epidemic in the United Kingdom and internationally (2).

Despite extensive knowledge about the spread of BSE through contaminated MBM, the source of BSE in Europe remains an unsolved mystery (2). It has been proposed that BSE could be derived from a cross-species infection, perhaps through contamination of MBM by scrapie-infected sheep tissues (see the figure). Alternatively, BSE may have been an endemic disease in cattle that went unnoticed because of its low level of horizontal transmission. Lastly, BSE might have originated by "spontaneous" misfolding of the normal cellular prion protein into the disease-associated abnormal isoform (3), which is postulated to be the infectious agent or "prion."


Five possible sources of BSE in North American cattle. Sheep, deer, and elk could spread prion diseases (TSEs) to cattle through direct animal contact or contamination of pastures. Endemic BSE has not been proven to exist anywhere in the world, but it is difficult to exclude this possibility because of the inefficient spread of BSE infectivity between individual animals (2). BSE caused by spontaneous misfolding of the prion protein has not been proven.
CREDIT: KATHARINE SUTLIFF/SCIENCE


Spontaneous protein misfolding is not a new phenomenon as proteins are known to sometimes misfold after synthesis. Cells in turn have devised ingenious ways to deal with this problem. These include molecular chaperone proteins that bind to misfolded proteins and help them to unfold, and organelles called proteosomes that degrade misfolded or unwanted proteins. However, although misfolded prion proteins have been generated in test tubes as well as in cultured cells, it has been difficult to demonstrate that such misfolded abnormal prion proteins are infectious (4, 5). Even the most recent data do not prove conclusively that infectivity has been generated in vitro because misfolded synthetic prion proteins were not able to transfer disease directly to wild-type mice (6). To obtain infectivity and subsequent prion disease, the misfolded proteins had to be inoculated and incubated for 1 to 2 years in transgenic mice that overexpressed a mutant version of the prion protein. Previous data from this group showed that transgenic mice expressing high amounts of prion protein developed neurological disease without inoculation of misfolded prion protein (7). Thus, at the biochemical level, the critical attributes of the misfolded prion protein required for infectivity are not known, and misfolding of prion protein alone may not be sufficient to generate an infectious agent (8).
Nevertheless, the idea that BSE might originate due to the spontaneous misfolding of prion proteins has received renewed interest in the wake of reports suggesting the occurrence of atypical BSE (9-11). These results imply that new strains of cattle BSE might have originated separately from the main UK outbreak. Where and how might such strains have originated? Although such rare events cannot be studied directly, any number of sources of the original BSE strain could also explain the discovery of additional BSE strains in cattle (see the figure). However, it would be worrisome if spontaneous BSE were really a valid etiology because such a mechanism would be impossible to prevent--unlike other possible scenarios that could be controlled by large-scale eradication of TSE-positive animals.

Another way to look at this problem is to examine evidence for possible spontaneous TSE disease in other animals besides cattle. Spontaneous BSE would be extremely difficult to detect in cattle, where horizontal spread is minimal. However, in the case of the sheep TSE disease, scrapie, which spreads from ewes to lambs at birth as well as between adults, spontaneous disease should be detectable as new foci of clinical infection. In the early 1950s scrapie was eradicated in both Australia and New Zealand, and the mainland of both these countries has remained scrapie-free ever since. This scrapie-free status is not the result of selection of sheep resistant to scrapie because sheep from New Zealand are as susceptible as their UK counterparts to experimental scrapie infection (12). These experiments of man and nature appear to indicate that spontaneous clinical scrapie does not occur in sheep. Similarly, because CWD is known to spread horizontally, the lack of CWD in the deer or elk of eastern North America but its presence in western regions would also argue against a spontaneous disease mechanism. This is particularly noteworthy in New Zealand, where there are large numbers of deer and elk farms and yet no evidence of spontaneous CWD. If spontaneous scrapie does not occur in sheep or deer, this would suggest that spontaneous forms of BSE and sporadic Creutzfeldt-Jakob disease (sCJD) are unlikely to be found in cattle or humans. The main caveat to this notion is that spontaneous disease may arise in some animal species but not others. In humans, sCJD--which is considered by some researchers to begin by spontaneous misfolding of the prion protein--usually takes more than 50 years to appear. Thus, in animals with a shorter life-span, such as sheep, deer, and cattle, an analogous disease mechanism might not have time to develop.

What can we conclude so far about BSE in North America? Is the BSE detected in two North American cows sporadic or spontaneous or both? "Sporadic" pertains to the rarity of disease occurrence. "Spontaneous" pertains to a possible mechanism of origin of the disease. These are not equivalent terms. The rarity of BSE in North America qualifies it as a sporadic disease, but this low incidence does not provide information about cause. For the two reported North American BSE cases, exposure to contaminated MBM remains the most likely culprit. However, other mechanisms are still possible, including cross-infection by sheep with scrapie or cervids with CWD, horizontal transmission from cattle with endemic BSE, and spontaneous disease in individual cattle. Based on our understanding of other TSEs, the spontaneous mechanism is probably the least likely. Thus, "idiopathic" BSE--that is, BSE of unknown etiology--might be a better term to describe the origin of this malady.

What does all this imply about testing cattle for BSE in North America? Current testing in the United States indicates that BSE is rare (one positive result in 40,000 cattle tested). However, additional testing of 200,000 head of slaughtered cattle over the next 1 to 2 years, as recently proposed by the U.S. Department of Agriculture (USDA), should tell us the incidence more precisely. Nevertheless, if any rare cases are detected, we may still not know their origin. If evidence arises of a focal occurrence of BSE, we might gain important insight into unexpected sources of contamination. However, because current tests do not seem to be able to detect BSE in infected animals less than 30 months of age, even more extensive testing will not completely guarantee the negative status of younger animals in the food chain. Therefore, the alternative option of testing all slaughtered cattle, as implemented in some countries such as Japan, would appear to provide little additional benefit. This fact has been acknowledged as the basis for a new agreement between the United States and Japan aimed at reestablishing the beef trade between the two countries.

One problem with the current U.S. testing program was the announcement a few months ago of unconfirmed positive BSE tests in two additional North American animals that were subsequently found to be negative when tested with the more accurate method of Western blotting. The public release of information about unconfirmed positive tests detected by the rapid test used for mass screening may be a good idea in the interest of openness, but it has the potential to create unwarranted anxiety. If unconfirmed positives are a frequent occurrence, it would seem reasonable to follow a more cautious approach and wait until confirmatory testing is complete before publicly announcing the details.

Based on the experience of many European countries, the mainstays of controlling BSE in cattle and avoiding spread to humans are threefold: first, eliminate feeding of ruminant tissues to ruminants; second, remove high-risk cattle tissues from human food; and third, continue to test for BSE in cattle in order to monitor progress with the elimination of the disease on a local and national basis. In the next 12 months, after extensive USDA test results are available, the extent of any possible BSE spread in the United States will be better documented. But, in fact, the United States and Canada have already instituted the most important steps to prevent the spread of cattle BSE in advance of the results--that is, a ban on feeding ruminant MBM to other ruminants and removal of high-risk tissues from meat for human consumption. It is hoped that the new data will not deviate enough from previous predictions to require further measures for management of this problem. The most important line of defense against any possible spread of BSE will be to maintain strict vigilance in the implementation of the current regulations.

References


S. B. Prusiner, Proc. Natl. Acad. Sci. U.S.A 95, 13363 (1998) [Medline].
P. G. Smith, R. Bradley, Br. Med. Bull. 66, 185 (2003) [Medline].
C. Weissmann, A. Aguzzi, Curr. Opin. Neurobiol. 7, 695 (1997) [Medline].
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R. Chiesa et al., J. Virol. 77, 7611 (2003) [Medline].
G. Legname et al., Science 305, 673 (2004).
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Y. Yamakawa et al., Jpn. J. Infect. Dis. 56, 221 (2003) [Medline].
C. Casalone et al., Proc. Natl. Acad. Sci. U.S.A. 101, 3065 (2004) [Medline].
E. F. Houston et al., J. Gen. Virol. 83, 1247 (2002) [Medline].


http://www.sciencemag.org/cgi/content/full/305/5692/1918




US atypical BSE - further details

As reported in the last BSE Report (Which? BSE May 2006) French research findings

concerning the two most recent cases of BSE in the USA suggest that these cases were

not typical of BSE in cattle and may reflect a sporadic form of the disease.

I

n the two US cases, discovered in herds in Texas and Alabama, threre was an absence

of telltale spongy lesions caused by prions. In addition, the prions in brain tissue

samples from these cows seemed to be distributed differently from the classic form.

Laboratory studies on mice in France showed that both the classic and atypical strains

could be spread from one animal to another, but the atypical strain might happen

spontaneously in cattle. The Texas and Alabama cows were older animals, as were

some of the other animals in Europe with seemingly atypical forms of BSE.31

Linda Detwiler, a former Agriculture Department veterinarian who consults for major

food companies, cautioned against making that assumption. "I think it's kind of early to

say that would be the case," Detwiler said. Other theories, she said, suggest the

atypical strain might come from a mutation of BSE or even from a related disease in

sheep.

The US Agriculture Department has stated that whatever the cause there is no reason

to change federal testing or control measures. "It's most important right now, till the

science tells us otherwise, that we treat this as BSE regardless," the department's chief

veterinarian, John Clifford, said in an interview. ...


http://www.which.co.uk/files/application/pdf/bserep0606-445-89308.pdf



TSS
 

TimH

Well-known member
PORKER said:
Hay timmy , Lifes Cheap ,Go ahead an enjoy it your way!

Hey Porky, Talk is cheap, too. Why not be a hero and post what bse-tester, flounder and R2 cannot?.........PROOF that prions are present in the muscle tissue of cattle. Can't do that??? Then how about some PROOF that vCJD is caused by eating beef????? C'mon PORKY, show us some evidence!!!!
You go ahead and enjoy your unproven theories(fairy tales) if you think it will help create demand for..........

www.scoringag.com

Ooops, another plug for ya' , buddy!!!! :)
 

TimH

Well-known member
reader (the Second) said:
Life is tough Tim but exercise is a better way to relieve stress than pissing on people in cyberspace :D

If you think life is tough at your age, try 20 years from now, when you're my age and you or your spouse (or boyfriend) may get a terminal illness and die. When your work no longer values smart older people. When you have to work hard at your health. When your parents if they are still alive are in frail health and you'll have to face taking care of them any minute.

Yep, life is tough but in spite of all I have seen and endured, I'm not pissing on people in real life or cyber world. But then thankfully, I don't have that much testosterone.

:roll: :roll: :roll:

And your scientific evidence that prions have been found in the muscle tissue of cattle is where??? And your evidence that vCJD is caused by eating beef is where???
Every time you suggest that any of the above is true, without being able to prove it, you are pissing on every ranch/farm/beef producer in the cyber world and the real world.
One question R2, did your husband's death have ANYTHING to do with beef?? As near as I can tell it was due to IATROGENIC transmission of CLASSIC CJD. Is this not correct???
I'll let the "boyfriend" thing slide......but be advised, do not push the envelope of my good nature. Your sympathy points were all used up many months ago as far as I am concerned .
I'll let the "testosterone" comment slide as well. That's the difference between you and me. I'm not playing politics.Only pointing out the facts. You(and others) assume readers of this forum are stupid and gullible. I assume that most are literate and intelligent. Capable of independant thought.
Go ahead and question my intelligence or reading comprehension now and I will copy and paste some excerpts from some of flounder's posts.
Such as this....
Based on the experience of many European countries, the mainstays of controlling BSE in cattle and avoiding spread to humans are threefold: first, eliminate feeding of ruminant tissues to ruminants; second, remove high-risk cattle tissues from human food; and third, continue to test for BSE in cattle in order to monitor progress with the elimination of the disease on a local and national basis. In the next 12 months, after extensive USDA test results are available, the extent of any possible BSE spread in the United States will be better documented. But, in fact, the United States and Canada have already instituted the most important steps to prevent the spread of cattle BSE in advance of the results--that is, a ban on feeding ruminant MBM to other ruminants and removal of high-risk tissues from meat for human consumption. It is hoped that the new data will not deviate enough from previous predictions to require further measures for management of this problem. The most important line of defense against any possible spread of BSE will be to maintain strict vigilance in the implementation of the current regulations.

Time to jump on that exercise bike yet, R2??? Perhaps a little HRT is in order at "your age".
See how easy it is to make it personal??

Post the proof or admit that it is non-existant.......or try to out insult me.It's your call.
 

flounder

Well-known member
> So where is this proof that Tim is looking for. I would like to see it as

> well.

it's there, and it's been posted on this board multiple times. once again, bse has been transmitted to a multitude of species orally and via the inoculation, including primates. however, i believe the inculation route to be more effective. you cannot prove transmission to humans in the lab because it is against the law. so the next best thing is the primate. as i said before, the tse agent has been found in the muscle tissue of a multitude of species, and now it has been found in tissues other than CNS in the bovine, and it is only a matter of time and testing with more sensitive testing, that it will be found in the muscle tissue of the bovine.
of course, i would expect nothing less from some of the industry on this board like timmyboy and big muddy that would rather disregard the science and believe the martians are responsible. :lol2: :lol2: :cboy:

tss
 

flounder

Well-known member
tim wrote,

One question R2, did your husband's death have ANYTHING to do with beef?? As near as I can tell it was due to IATROGENIC transmission of CLASSIC CJD. Is this not correct??? ...............



holy mad cow timmyboy, those folks that passed the TSE agent via surgical tools did not develop that TSE spontaneously, they got it from a source, that
being cattle, sheep, deer, elk, 2nd passage medical/dental/surgical, etc. WAKEUP TIMMYBOY! do you actually produce a commodity for the consumer?
your starting to scare me now.

FACT ;

The current risk of acquiring vCJD from eating beef (muscle meat) and beef products produced from cattle in countries with at least a possibly increased risk of BSE cannot be determined precisely..........



http://www2.ncid.cdc.gov/travel/yb/utils/ybGet.asp?section=dis&obj=madcow.htm


tim, I don't believe i ever stated that BSE HAD been documented yet in the muscle of the bovine, and if so, maybe old tim can produce this. i have stated time and time again it most likely will be detected once testing with the most up to date sensitve testing methods are used in a large test sample, with different loads, and i am very interested to see the SRM distribution in the new BASE strain that is very similar to the sporadic CJD, not the nvCJD. i have stated that it HAS been detected in many other species, and i will document them again just for TIM, and i will also state that is my opinion that it WILL be detected in the bovine muscle eventually, just a matter of time, and it was just detected outside the CNS for the first time, PrPSc has been detected in the peripheral nerves (sciatic nerve, tibial nerve, vagus nerve) of a cow in Japan (see study below). ...



Pathological prion protein in muscles of hamsters and mice infected with rodent-adapted BSE or vCJD
Achim Thomzig1,, Franco Cardone2,, Dominique Krüger1, Maurizio Pocchiari2, Paul Brown3 and Michael Beekes1

1 Robert Koch-Institut (P24 – Transmissible Spongiform Encephalopathies), Nordufer 20, 13353 Berlin, Germany
2 Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
3 7815 Exeter Road, Bethesda, MD 20814, USA


Correspondence
Michael Beekes
[email protected]

Recently, pathological prion protein (PrPTSE) was detected in muscle from sheep infected with scrapie, the archetype of transmissible spongiform encephalopathies (TSEs). This finding has highlighted the question of whether mammalian muscle may potentially also provide a reservoir for TSE agents related to bovine spongiform encephalopathy (BSE) and variant Creutzfeldt–Jakob Disease (vCJD). Here, results are reported from studies in hamsters and mice that provide direct experimental evidence, for the first time, of BSE- and vCJD-associated PrPTSE deposition in muscles. Our findings emphasize the need for further assessment of possible public-health risks from TSE involvement of skeletal muscle.


SNIP...


A. Thomzig and others



Table 1. Detection of PrPTSE in muscles of rodents infected intracerebrally with BSE or vCJD agents

Data represent the number of animals with PrPTSE in muscles/number of animals examined. Control, specimen from uninfected animals.

ND, Not done.

Muscle sample Hamster-adapted BSE Mouse-adapted BSE Mouse-adapted vCJD

Western blotting Immunohistochemistry Western blotting Western blotting

Control BSE Control BSE Control BSE Control vCJD

M. biceps femoris (hindlimb) 0/3 5/5 ND ND 0/2 1/4 0/2 2/4

M. tibialis cranialis (hindlimb) 0/3 5/5 0/2 2/2 0/2 0/4 0/2 1/4

M. triceps brachii (forelimb) 0/3 5/5 ND ND 0/2 2/4 0/2 2/4

M. extensor carpi radialis (forelimb) 0/3 5/5 ND ND 0/2 0/4 0/2 2/4

M. trapezius (shoulder) 0/3 5/5 ND ND 0/2 1/4 0/2 1/4

M. masseter (head) 0/3 5/5 0/2 2/2 0/2 0/4 0/2 2/4

M. psoas major (back) 0/3 5/5 0/2 2/2 0/2 2/4 0/2 1/4

M. lingualis (tongue) 0/3 5/5 0/2 2/2 0/2 1/4 0/2 0/4

Heart 0/3 5/5* ND ND 0/2 0/4 0/2 0/4

*Only weak signals for PrPTSE.





Fig. 1. (a) Western blot detection of PrP27–30, the protease-resistant core of PrPTSE, extracted from muscles and sciatic

nerve of terminally ill hamsters infected intracerebrally with hamster-passaged BSE agent. Lanes 1 and 8, proteinase

K-digested brain homogenate from BSE-infected hamsters, containing 5610”7 g brain tissue; lanes 2–7 and 9, skeletal

muscles from hindlimb (2, 3), forelimb (4, 5), shoulder (6), head (7) and back (9); lane 10, tip of tongue; lane 11, heart; lane

12, sciatic nerve; lane 13, skeletal muscles from uninfected control hamster, spiked before extraction with 5610”6 g brain

homogenate from BSE-infected hamsters; lane 14, skeletal muscle from an uninfected control hamster. All examined hamster

muscle samples corresponded to 20–50 mg tissue. (b) Western blot detection of PrP27–30 extracted from muscles of

terminally ill mice infected intracerebrally with mouse-adapted BSE (lanes 1–3) and vCJD (lanes 4–6) agent. Lane 1, muscle

from hindlimb; lanes 2–3, different muscles from forelimb; lane 4, muscle from hindlimb; lanes 5–6, different muscles from

forelimb; lane 7, skeletal muscle from uninfected control mouse, spiked before extraction with 5610”5 g brain homogenate

from vCJD-infected mice; lanes 8–9, skeletal muscles from uninfected control mouse. All examined murine muscle samples

corresponded to 15–40 mg tissue. (c, d) Location of PrPTSE in lingual muscle fibres of BSE-infected hamsters visualized by

PrP immunohistochemistry. Brownish granular immunostaining demonstrates PrPTSE deposition predominantly in the region of

the fibre surface (c, arrowheads), but also scattered within myocytes (d, arrows). Insets show higher magnification of muscle

fibres marked by an asterisk. Bars, 20 mm.



These authors contributed equally to this work.



http://vir.sgmjournals.org/cgi/content/abstract/87/1/251



From: TSS () Subject: PrPSc distribution of a natural case of bovine spongiform encephalopathy

Date: August 8, 2005 at 12:28 pm PST

PrPSc distribution of a natural case of bovine spongiform encephalopathy

Yoshifumi Iwamaru, Yuka Okubo, Tamako Ikeda, Hiroko Hayashi, Mori- kazu Imamura,

Takashi Yokoyama and Morikazu Shinagawa

Prion Disease Research Center, National Institute of Animal Health, 3-1-5 Kannondai,

Tsukuba 305-0856 Japan [email protected]

Abstract Bovine spongiform encephalopathy (BSE) is a disease of cattle that causes progressive neurodegeneration

of the central nervous system. Infectivity of BSE agent is accompanied with an abnormal isoform of prion protein (PrPSc).

The specified risk materials (SRM) are tissues potentially carrying BSE infectivity. The following tissues are designated as SRM in Japan:

the skull including the brain and eyes but excluding the glossa and the masse- ter muscle, the vertebral column excluding the vertebrae of

the tail, spinal cord, distal illeum. For a risk management step, the use of SRM in both animal feed or human food has been prohibited.

However, detailed PrPSc distribution remains obscure in BSE cattle and it has caused controversies about definitions of SRM. Therefore we

have examined PrPSc distribution in a BSE cattle by Western blotting to reassess definitions of SRM. The 11th BSE case in Japan was

detected in fallen stock surveillance. The carcass was stocked in the refrigerator. For the detection of PrPSc, 200 mg of tissue samples

were homogenized. Following collagenase treatment, samples were digested with proteinase K. After digestion, PrPSc was precipitated

by sodium phosphotungstate (PTA). The pellets were subjected to Western blotting using the standard procedure. Anti-prion protein

monoclonal antibody (mAb) T2 conjugated horseradish peroxidase was used for the detection of PrPSc. PrPSc was detected in brain,

spinal cord, dorsal root ganglia, trigeminal ganglia, sublingual ganglion, retina. In addition, PrPSc was also detected in the peripheral

nerves (sciatic nerve, tibial nerve, vagus nerve). Our results suggest that the currently accepted definitions of SRM in 9/13/2005


179
Page 10 of 17 BSE cattle may need to be reexamined. T. Kitamoto (Ed.)
PRIONS
Food and Drug Safety
===============



Prions in Skeletal Muscles of Deer with Chronic Wasting Disease


Rachel C. Angers,1* Shawn R. Browning,1*† Tanya S. Seward,2 Christina J.
Sigurdson,4‡ Michael W. Miller,5 Edward A. Hoover,4 Glenn C. Telling1,2,3§

1Department of Microbiology, Immunology and Molecular Genetics, 2Sanders
Brown Center on Aging, 3Department of Neurology, University of Kentucky,
Lexington, KY 40536, USA. 4Department of Microbiology, Immunology and
Pathology, Colorado State University, Fort Collins, CO 80523, USA. 5Colorado
Division of Wildlife, Wildlife Research Center, Fort Collins, CO 80526, USA.

*These authors contributed equally to this work.

†Present address: Department of Infectology, Scripps Research Institute,
5353 Parkside Drive, RF-2, Jupiter, Florida, 33458, USA.

‡Present address: Institute of Neuropathology, University of Zurich,
Schmelzbergstrasse 12, 8091 Zurich, Switzerland.

§To whom correspondence should be addressed: E-mail: [email protected]

Prions are transmissible proteinaceous agents of mammals that cause fatal
neurodegenerative diseases of the central nervous system (CNS). The presence
of infectivity in skeletal muscle of experimentally infected mice raised the
possibility that dietary exposure to prions might occur through meat
consumption (1). Chronic wasting disease (CWD), an enigmatic and contagious
prion disease of North American cervids, is of particular concern. The
emergence of CWD in an increasingly wide geographic area and the
interspecies transmission of bovine spongiform encephalopathy (BSE) to
humans as variant Creutzfeldt Jakob disease (vCJD) have raised concerns
about zoonotic transmission of CWD.

To test whether skeletal muscle of diseased cervids contained prion
infectivity, Tg(CerPrP)1536 mice (2) expressing cervid prion protein
(CerPrP), were inoculated intracerebrally with extracts prepared from the
semitendinosus/semimembranosus muscle group of CWD-affected mule deer or
from CWD-negative deer. The availability of CNS materials also afforded
direct comparisons of prion infectivity in skeletal muscle and brain. All
skeletal muscle extracts from CWD-affected deer induced progressive
neurological dysfunction in Tg(CerPrP)1536 mice with mean incubation times
ranging between 360 and ~490 d, whereas the incubation times of prions from
the CNS ranged from ~230 to 280 d (Table 1). For each inoculation group, the
diagnosis of prion disease was confirmed by the presence of PrPSc in the
brains of multiple infected Tg(CerPrP)1536 mice (see supporting online
material for examples). In contrast, skeletal muscle and brain material from
CWD-negative deer failed to induce disease in Tg(CerPrP)1536 mice (Table 1)
and PrPSc was not detected in the brains of sacrificed asymptomatic mice as
late as 523 d after inoculation (supporting online material).

Our results show that skeletal muscle as well as CNS tissue of deer with CWD
contains infectious prions. Similar analyses of skeletal muscle BSE-affected
cattle did not reveal high levels of prion infectivity (3). It will be
important to assess the cellular location of PrPSc in muscle. Notably, while
PrPSc has been detected in muscles of scrapie-affected sheep (4), previous
studies failed to detect PrPSc by immunohistochemical analysis of skeletal
muscle from deer with natural or experimental CWD (5, 6). Since the time of
disease onset is inversely proportional to prion dose (7), the longer
incubation times of prions from skeletal muscle extracts compared to matched
brain samples indicated that prion titers were lower in muscle than in CNS
where infectivity titers are known to reach high levels. Although possible
effects of CWD strains or strain mixtures on these incubation times cannot
be excluded, the variable 360 to ~490 d incubation times suggested a range
of prion titers in skeletal muscles of CWD-affected deer. Muscle prion
titers at the high end of the range produced the fastest incubation times
that were ~30% longer than the incubation times of prions from the CNS of
the same animal. Since all mice in each inoculation group developed disease,
prion titers in muscle samples producing the longest incubation times were
higher than the end point of the bioassay, defined as the infectious dose at
which half the inoculated mice develop disease. Studies are in progress to
accurately assess prion titers.

While the risk of exposure to CWD infectivity following consumption of
prions in muscle is mitigated by relatively inefficient prion transmission
via the oral route (, these


results show that semitendinosus/semimembranosus muscle, which is likely to
be consumed by humans, is a significant source of prion infectivity. Humans
consuming or handling meat from CWD-infected deer are therefore at risk to
prion exposure.

References and Notes

snip...end


=================

(American Journal of Pathology. 2006;168:927-935.)
© 2006 American Society for Investigative Pathology
Detection and Localization of PrPSc in the Skeletal Muscle of Patients with Variant, Iatrogenic, and Sporadic Forms of Creutzfeldt-Jakob Disease
Alexander H. Peden, Diane L. Ritchie, Mark W. Head and James W. Ironside

From the National Creutzfeldt-Jakob Disease Surveillance Unit and Division of Pathology, School of Molecular and Clinical Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom

Variant Creutzfeldt-Jakob disease (vCJD) differs from other human prion diseases in that the pathogenic prion protein PrPSc can be detected to a greater extent at extraneuronal sites throughout the body, principally within lymphoid tissues. However, a recent study using a high-sensitivity Western blotting technique revealed low levels of PrPSc in skeletal muscle from a quarter of Swiss patients with sporadic CJD (sCJD). This posed the question of whether PrPSc in muscle could also be detected in vCJD, sCJD, and iatrogenic (iCJD) patients from other populations. Therefore, we have used the same high-sensitivity Western blotting technique, in combination with paraffin-embedded tissue blotting, to screen for PrPSc in muscle tissue specimens taken at autopsy from 49 CJD patients in the United Kingdom. These techniques identified muscle PrPSc in 8 of 17 vCJD, 7 of 26 sCJD, and 2 of 5 iCJD patients. Paraffin-embedded tissue blotting analysis showed PrPSc in skeletal muscle in localized anatomical structures that had the morphological and immunohistochemical characteristics of nerve fibers. The detection of PrPSc in muscle tissue from all forms of CJD indicates the possible presence of infectivity in these tissues, suggesting important implications for assessing the potential risk of iatrogenic spread via contaminated surgical instruments.

=================



IN ADDITION ;



14 goats inoculated with muscle from scrapie-infected goats one developed clinical disease.

(Pattison and Millison, 1962; Pattison, 1990). A low median lethal dose was also observed in

muscle of TME-infected mink (Marsh et al, 1969). Transgenic mice inoculated

with scrapie have been reported to produce prions in muscle previously (Bosque

et al, 1997).



================



whether you accept mouse studies or not, pathological prion protein in muscles of hamsters and mice infected

with rodent-adapted BSE or vCJD cannot be ignored.

I do hope science proves no TSE infectivity in the muscle of the bovine, but TSE science has moved forward at a cows pace,

but it is moving forward, time will tell. BUT from the latest data, where the data use to say TSE did not transmit to this species

or that species, new data from more sensitive testing has in fact proven TSE has been documented in the muscle of multiple species,

and as i said, time will tell if they document it in the bovine muscle. ITs high time that extensive research is done in this area

of science. 3 decades and still debating this is not acceptable, especially with the incubation period involved. ...TSS
 

TimH

Well-known member
flounder wrote
tim, I don't believe i ever stated that BSE HAD been documented yet in the muscle of the bovine, and if so, maybe old tim can produce this.

How about this........
BMR wrote
So where is this proof that Tim is looking for. I would like to see it as
> well.

flounder responded

it's there, and it's been posted on this board multiple times.

That was easy. It was in this very thread.

Your turn.
 

TimH

Well-known member
R2 wrote-

TimH denies that there is a relationship between BSE and vCJD. In that, he is in a tiny minority, even on this forum. Unfortunately, for him, all evidence is to the contrary. It is because he denies the BSE - vCJD link that he must argue that there could not be prions in muscle.

Show me where I denied this. I've said that the supposed link is only circumstancial, at best. BSE and vCJD are both classified as TSEs and they both seemed to appear in the UK at about the same time. Show me all this "evidence to the contrary".

Let's see, around 160 cases of vCJD have been diagnosed worldwide. Mostly in Britain. They have also diagnosed 180,000+ cases of BSE in Britain. According to some, less than 1 gram of "infective" beef can trigger vCJD in humans. Millions of pounds of beef are consumed each year. 160 cases of vCJD in 20 plus years. Does not compute.
Don't get sidetracked R2. If you have any evidence that the
"link" between vCJD and beef is anything more than circumstancial, I'd love to see it.
 

bse-tester

Well-known member
part of a study found.

Pathophysiology of peripheral PrPSc deposition in muscles.
In experiments with transgenic mice exhibiting a four- to eightfold overexpression of the cellular isoform of the prion protein (PrPC) in myofibers under the control of myocyte-specific promoters, Bosque et al. (11) showed intrinsic replication of infectivity in muscles injected with scrapie agent. Here, with the more natural route of peroral infection, we have provided direct experimental evidence for the deposition of PrPSc in myofibers, particularly subsarcolemmally, and found that the deposition of this protein in muscles is also endoneurally associated with nerve fibers. Furthermore, the distribution patterns of PrPSc observed in muscles conspicuously resembled those known for the innervation of motor units (31, 32). Taken together, these findings are highly indicative of spread of infection from motor neurons in the spinal cord via axonal projections to neuromuscular junctions and on from there postsynaptically into muscle fibers. The results from the Western blot studies clearly show that PrPSc can be detected in muscles only shortly before the onset of clinical symptoms, that is, at a time point when the CNS is already heavily loaded with PrPSc and infectivity. This, again, would most plausibly be explained by projections of the peripheral nervous system mediating centrifugal infection of muscles from the spinal cord. Further time-course studies will be necessary, however, to validate the proposed neural spreading pathway and to elucidate, or rule out, the relevance of alternative mediators for muscle invasion such as lymph and blood or neural pathways linked with the centripetal ascension of TSE agent to the CNS.

Risks for public health and protection of consumers and patients.
What conclusions regarding the risks for public health emanating from "Prions in skeletal muscle" can be drawn from the findings described in this report?

For the reasons outlined above, the experimental paradigm used in our study is likely to provide a relevant model on the issue of muscle contamination. It probably reflects a worst-case rather than a best-case scenario, however, because the levels of infectivity and PrPSc produced in the CNS and other neural tissues of 263K scrapie-infected hamsters generally tend to be higher than in nonexperimental TSEs. Indeed, other than for caprine scrapie (7) or sporadic CJD (14), no infectivity or PrPSc has been detected so far in skeletal muscles of cattle with BSE (10).

If the findings in the hamster model were confirmed, to a varying degree, in ovine scrapie, BSE, or CWD, significant deposition of PrPSc in muscles of affected sheep, cattle, and elk or deer would be expected to occur only at relatively late stages of preclinical infection, with the bulk of muscle-associated PrPSc accumulating during clinical disease. At those stages of incubation, however, the TSE routine tests currently in use should allow both an identification of affected animals (34) with high reliability and their safe disposal. Thus, our findings strongly support the schemes for active TSE testing of animals that have already been implemented in several countries as an efficient precautionary measure to prevent muscle tissue potentially contaminated with infectious TSE agent from entering the food chain.

In addition to recent findings in patients with sporadic CJD (14), our observations in the hamster model corroborate concerns that muscles from inconspicuous patients preclinically incubating CJD or vCJD may represent a potential risk tissue for the nosocomial transmission of human TSE agents. Epidemiological evidence substantiating this hypothetical hazard has not been reported, however, and in any case the risk can be considered as effectively addressed by comprehensive precautionary measures already implemented for infection control in nosocomial settings. Particularly, recommended procedures for the routine maintenance (cleaning, disinfection, and sterilization) of surgical instruments (35, 36) aimed at the reliable removal and inactivation of unrecognized contaminations with infectious agents are expected to substantially reduce iatrogenic risks possibly originating from TSE agents in muscles — if they are firmly observed.

Since 2002, a considerable body of new data on PrPSc and TSE infectivity in muscles of experimentally infected rodents and patients with sporadic CJD has been compiled (11-14). It remains to be examined in future studies whether, and to what extent, these findings can be transferred to nonexperimental scrapie, BSE, and CWD, or to vCJD in humans. Special attention should be paid to food products containing ruminant or cervid tongue, given the observations reported here and elsewhere (13). In any case, the data available so far leave no doubt that, 40 years after Pattison and Millson (7) reported finding the scrapie agent in muscle tissue of an experimentally infected goat, a topical field of TSE research has been (re)opened.

More to follow.
 

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