Alzheimer’s disease, iatrogenic, and Transmissible Spongiform Encephalopathy TSE Prion disease, that is the question ???
>>> The only tenable public line will be that "more research is required’’ <<<
>>> possibility on a transmissible prion remains open<<<
O.K., so it’s about 23 years later, so somebody please tell me, when is "more research is required’’ enough time for evaluation ?
[9. Whilst this matter is not at the moment directly concerned with the iatrogenic CJD cases from hgH, there remains a possibility of litigation here, and this presents an added complication. There are also results to be made available shortly (1) concerning a farmer with CJD who had BSE animals, (2) on the possible transmissibility of Alzheimer’s and (3) a CMO letter on prevention of iatrogenic CJD transmission in neurosurgery, all of which will serve to increase media interest.]
snip...see full Singeltary Nature comment here;
see Singeltary comments to Plos ;
Subject: 1992 IN CONFIDENCE TRANSMISSION OF ALZHEIMER TYPE PLAQUES TO PRIMATES POSSIBILITY ON A TRANSMISSIBLE PRION REMAINS OPEN
BSE101/1 0136
IN CONFIDENCE
CMO
From: . Dr J S Metiers DCMO 4
November 1992
TRANSMISSION OF ALZHEIMER TYPE PLAQUES TO PRIMATES
1. Thank you for showing me Diana Dunstan's letter. I am glad that MRC have recognised the public sensitivity of these findings and intend to report them in their proper context. 'This hopefully will avoid misunderstanding and possible distortion by the media to portray the results as having more greater significance than the findings so far justify.
2. Using a highly unusual route of transmission (intra-cerebral injection) the researchers have demonstrated the transmission of a pathological process from two cases one of severe Alzheimer's disease the other of Gerstmann-Straussler disease to marmosets. However they have not demonstrated the transmission of either clinical condition as the "animals were behaving normally when killed". As the report emphasises the unanswered question is whether the disease condition would have revealed itself if the marmosets had lived longer. They are planning further research to see if the conditions, as opposed to the partial pathological process, is transmissible. what are the implications for public health?
3. The route 'of transmission is very specific and in the natural state of things highly unusual. However it could be argued that the results reveal a potential risk, in that brain tissue from these two patients has been shown to transmit a pathological process. Should therefore brain tissue from such cases be regarded as potentially infective? Pathologists, morticians, neuro surgeons and those assisting at neuro surgical procedures and others coming into contact with "raw" human brain tissue could in theory be at risk.
However, on a priori grounds given the highly specific route of transmission in these experiments that risk must be negligible if the usual precautions for handling brain tissue are observed. 1
92/11.4/1.1
BSE101/1 0137 4.
The other dimension to consider is the public reaction. To some extent the GSS case demonstrates little more than the transmission of BSE to a pig by intra-cerebral injection. If other prion diseases can be transmitted in this way it is little surprise that some pathological findings observed in GSS were also transmissible to a marmoset. But the transmission of features of Alzheimer's pathology is a different matter, given the much greater frequency of this disease and raises the unanswered question whether some cases are the result of a transmissible prion.
The only tenable public line will be that "more research is required’’ before that hypothesis could be evaluated. The possibility on a transmissible prion remains open. In the meantime MRC needs carefully to consider the range and sequence of studies needed to follow through from the preliminary observations in these two cases. Not a particularly comfortable message, but until we know more about the causation of Alzheimer's disease the total reassurance is not practical.
J S METTERS Room 509 Richmond House Pager No: 081-884 3344 Callsign: DOH 832 llllYc!eS 2 92/11.4/1.2
>>> The only tenable public line will be that "more research is required’’ <<<
>>> possibility on a transmissible prion remains open<<<
O.K., so it’s about 23 years later, so somebody please tell me, when is "more research is required’’ enough time for evaluation ?
Re-Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy
Nature 525, 247?250 (10 September 2015) doi:10.1038/nature15369 Received 26 April 2015 Accepted 14 August 2015 Published online 09 September 2015 Updated online 11 September 2015 Erratum (October, 2015)
snip...see full Singeltary Nature comment here;
Alzheimer's disease
let's not forget the elephant in the room. curing Alzheimer's would be a great and wonderful thing, but for starters, why not start with the obvious, lets prove the cause or causes, and then start to stop that. think iatrogenic, friendly fire, or the pass it forward mode of transmission. think medical, surgical, dental, tissue, blood, related transmission. think transmissible spongiform encephalopathy aka tse prion disease aka mad cow type disease...
Commentary: Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy
Self-Propagative Replication of Ab Oligomers Suggests Potential Transmissibility in Alzheimer Disease
*** Singeltary comment PLoS ***
Alzheimer’s disease and Transmissible Spongiform Encephalopathy prion disease, Iatrogenic, what if ?
Posted by flounder on 05 Nov 2014 at 21:27 GMT
Ann N Y Acad Sci. 1982;396:131-43.
Alzheimer's disease and transmissible virus dementia (Creutzfeldt-Jakob disease).
Brown P, Salazar AM, Gibbs CJ Jr, Gajdusek DC.
Abstract
Ample justification exists on clinical, pathologic, and biologic grounds for considering a similar pathogenesis for AD and the spongiform virus encephalopathies. However, the crux of the comparison rests squarely on results of attempts to transmit AD to experimental animals, and these results have not as yet validated a common etiology. Investigations of the biologic similarities between AD and the spongiform virus encephalopathies proceed in several laboratories, and our own observation of inoculated animals will be continued in the hope that incubation periods for AD may be even longer than those of CJD.
Sunday, November 22, 2015
*** Effect of heating on the stability of amyloid A (AA) fibrils and the intra- and cross-species transmission of AA amyloidosis
Abstract
Amyloid A (AA) amyloidosis is a protein misfolding disease characterized by extracellular deposition of AA fibrils. AA fibrils are found in several tissues from food animals with AA amyloidosis. For hygienic purposes, heating is widely used to inactivate microbes in food, but it is uncertain whether heating is sufficient to inactivate AA fibrils and prevent intra- or cross-species transmission. We examined the effect of heating (at 60 °C or 100 °C) and autoclaving (at 121 °C or 135 °C) on murine and bovine AA fibrils using Western blot analysis, transmission electron microscopy (TEM), and mouse model transmission experiments. TEM revealed that a mixture of AA fibrils and amorphous aggregates appeared after heating at 100 °C, whereas autoclaving at 135 °C produced large amorphous aggregates. AA fibrils retained antigen specificity in Western blot analysis when heated at 100 °C or autoclaved at 121 °C, but not when autoclaved at 135 °C. Transmissible pathogenicity of murine and bovine AA fibrils subjected to heating (at 60 °C or 100 °C) was significantly stimulated and resulted in amyloid deposition in mice. Autoclaving of murine AA fibrils at 121 °C or 135 °C significantly decreased amyloid deposition. Moreover, amyloid deposition in mice injected with murine AA fibrils was more severe than that in mice injected with bovine AA fibrils. Bovine AA fibrils autoclaved at 121 °C or 135 °C did not induce amyloid deposition in mice. These results suggest that AA fibrils are relatively heat stable and that similar to prions, autoclaving at 135 °C is required to destroy the pathogenicity of AA fibrils. These findings may contribute to the prevention of AA fibril transmission through food materials to different animals and especially to humans.
Purchase options Price * Issue Purchase USD 511.00 Article Purchase USD 54.00
WEDNESDAY, NOVEMBER 1, 2017
Blood-derived amyloid-β protein induces Alzheimer’s disease pathologies
*** Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery ***
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA Diagnosis and Reporting of Creutzfeldt-Jakob Disease
To the Editor:
In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.
Terry S. Singeltary, Sr Bacliff, Tex
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.
0 Comments:
Post a Comment
Subscribe to Post Comments [Atom]
<< Home