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Heslin, Donna E. "Lesion profiling in Creutzfeldt-Jakob disease." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58829.pdf.
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Bunn, Tristan. "Prion protein biochemistry in Creutzfeldt-Jakob disease." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/23281.
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Macleod, Margaret-Ann. "The clinico-pathological phenotype of sporadic Creutzfeldt-Jakob disease." Thesis, University of Edinburgh, 2002. http://hdl.handle.net/1842/28507.
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Creutzfeldt-Jakob Disease (CJD) is a rare neurodegenerative disorder of the human central nervous system. It occurs in four main forms, defined essentially according to aetiology: sporadic, variant, iatrogenic and familial. All forms of the disease are characterised by the deposition of an abnormal cellular protein, the prion protein (PrP^sc), within the brain. Definitive diagnosis depends on identifying this along with other neuropathological changes such as spongiform degeneration and astrocytic gliosis. To date variant CJD has followed a relatively stereotyped clinical course with fairly consistent pathological findings. However, various clinico-pathological phenotypes of sporadic CJD have been described. It is believed the disease phenotype is influenced by a number of factors including agent strain (PrP^res isotype being used as a surrogate marker), and genotype (particularly a polymorphism at codon 129 of the prion protein gene). Data on 99 cases of sporadic CJD and 43 cases of variant CJD were analysed. The sporadic CJD cases were divided into 6 sub-groups, according to genotype at codon 129 (either methionine homozygous, valine homozygous or heterozygous) and PrP^res isotype (either type 1 or 2A). Some trends in clinico-pathological phenotype were found. Notably, the methionine homozygous cases with type 1 PrP^res isotype formed the majority of cases and followed a reasonably uniform disease course. The other groups tended to include atypical cases. These differences did not achieve statistical significance and there was considerable overlap amongst cases. 14-3-3 protein and the use of MR imaging were analysed. The results suggest that these investigations may improve the diagnostic classification of sporadic CJD. The variant CJD cases followed a relatively consistent clinico-pathological course, consistent with a distinct aetiology and probably a distinct strain. The data do not support the hypothesis that different strains of the sporadic CJD agent cause distinct clinico-pathological phenotypes.
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Cordery, R. J. "The early diagnosis and management of Creutzfeldt-Jakob disease." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446588/.
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This thesis describes work undertaken to improve the early diagnosis of variant Creutzfeldt-Jakob disease (vCJD), using existing clinical and research tools. Twenty-one cases referred to the National Hospital for Neurology and Neurosurgery and St. Mary's Hospital, London with suspected vCJD completed participation in the study. Fifteen cases were confirmed with definite or probable vCJD and six were given alternative diagnoses. These six cases with alternative diagnoses formed a control group. Further controls were recruited from patients referred with sporadic and familial forms of prion disease. A neuropsychiatry questionnaire comprising a battery of standardised tests was formulated. Of those with definite or probable vCJD, 86% exhibited anxiety, 93% irritability, 64% agitation and 79% displayed evidence of severe depressive symptoms. Fifty seven percent experienced simple delusions, most commonly of theft and suspicion and 36% described misidentifications (mean 8 months from illness onset). Behavioural change was common to all cases, 79% with aggression, 71% emotional lability and 79% sleep problems. Comprehensive neuropsychology assessments from those with vCJD were compared with sporadic and familial cases. Moderate to severe intellectual decline is characteristic of vCJD and impairment affects all cognitive domains. Only a minority of the vCJD cases presented with perceptual impairment compared with 50% of sporadic and familial cases. The proportion of cases with nominal impairment in the familial disease group was significantly lower than in the variant and sporadic groups. Serial volumetric MR imaging was only possible in a subgroup of cases with familial CJD. The annual mean rate of whole brain atrophy was 2.05% compared to 0.25% in normal controls. Single voxel proton magnetic spectroscopy performed in three cases with vCJD showed a 2.5 fold (150%) increase in the mean myo-inositol concentration and 50% reduction in N-acetylaspartate in the pulvinar region. Similar changes were seen in the caudate nucleus where no signal change was detected on T2 weighted images. The key to early diagnosis still relies on a high index of suspicion for vCJD and early referral to the appropriate specialist services. First hand experience of the problems faced by patients prompted a second, parallel project to be undertaken. A survey was conducted of all UK consultant neurologists and old age psychiatrists to assess current practices in the diagnosis and management of young people with dementia. It was concluded that young people may be under investigated if managed solely by an old age psychiatrist and may not receive adequate follow up services if managed solely by a neurologist.
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Mackay, Graham. "Clinico-pathological phenotypes of sporadic CJD in relation to PpPres type." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202124.
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Zeidler, Martin. "A new variant of Creutzfeldt-Jakob disease in the United Kingdom." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274425.
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de, Vries Kay. "Caring for the person with variant Creutzfeldt-Jakob disease within the hospice service." Thesis, University of Surrey, 2006. http://epubs.surrey.ac.uk/842755/.
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This thesis explores the experience of caring for people with the new diseases of variant Creutzfeldt-Jakob disease (CJD) by hospice services. The experiences of the hospice staff and carers of five people, who had died, or were dying, as a result of variant CJD, at three different hospice sites in the South of England were explored. Data from four focus groups and 11 interviews, with hospice staff (included health care assistants, nurses, doctors and social workers) and family members, plus hospice patient records were analysed. Media material was also examined and used to inform the study. The thesis offers a theoretical explanation of these experiences developed through grounded theory methodology using an emergent fit design. It describes the event of the admission into the hospice service of a person with a new disease, that of variant CJD, and how the dying experience of these people was managed by both in-house and community hospice teams, 'Open systems' theory is used to assist in analysis and interpretation of the participant experiences, and as a means of 'contextualising' the hospice service. The hospice is presented as a metaphorical container within which dying is processed, and where the primary task of the organisation had a different emphasis and focus, depending on individual perspectives of participants. A theory of 'dealing with the unknown' was developed to explain the impact of this new disease on system equilibrium. The disease was a novelty and influenced admissions into the service and responses to the disease by others. It engendered the need for staff to use controlling practices to maintain the system balance. There were paradoxes between the practices of in-house and community teams, and between in- house and family member 'understanding' of how care was managed. The experience of caring for people with variant CJD was also profoundly humbling for participants. Humility was identified as a response to the realisation of limitations in relieving the suffering of people with variant CJD and their families. The study demonstrated change over time, where hospice staff moved from not knowing to becoming knowledgeable about managing the care of the person with variant CJD. The theory is complimented by and builds on existing theories of hospice practice.
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Choi, Young Pyo. "PrPSc complexity in different forms of Creutzfeldt-Jakob disease identified using biochemical approaches." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4798.
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Transmissible spongiform encephalopathies (TSEs) or prion diseases are a group of fatal neurodegenerative diseases affecting humans and animal species. Prion diseases are characterized by the conversion of the host encoded prion protein (PrPC) into a disease-associated isoform (PrPSc), which (according to the prion hypothesis) is thought to be the main component of the infectious agent. PrPSc has been traditionally distinguished from PrPC by its biochemical properties, such as partial resistance to proteolysis and detergent-insolubility. In the absence of a foreign nucleic acid genome associated with prion diseases, efforts to provide a molecular basis for the biological diversity of prions have focused on biochemical characterization of PrPSc. In Creutzfeldt-Jakob disease (CJD) and other forms of human prion disease, the biochemical characterization of PrPSc has been largely restricted to the analysis of PK-resistant fragments of PrPSc (PrPres) by Western blot. However, given recent findings on the complexity of PrPSc identified in laboratory prion strains, PrPres analysis alone may not provide a complete description of PrPSc present in CJD brains. For a more complete characterization of PrPSc in human prion diseases, this study investigated biochemical properties of PrPSc in different forms of CJD by employing approaches that differ in principle from conventional Western blot analysis of PrPres. The novel biochemical approaches used in this study have identified further complexity of PrPSc accumulated in CJD brains, not only between different forms of CJD but also within single cases of individual disease entities. In this study, the two biochemical criteria most frequently used to define PrPSc (3F4 epitope accessibility versus resistance to limited proteolysis) did not always correlate, indicating probable non-uniform distribution of PK-sensitive isoform of PrPSc within the same CJD brains. In variant CJD (vCJD) brains, the thalamic region, which is characterized by distinct neuropathological features, could also be distinguished from frontal cortex and cerebellum by the sedimentation profiles of PrPC and PrPSc on sucrose step gradients. Moreover, the conformational stability of PrPSc was found not to be uniform among human prion diseases and did not correlate with PrPres type or prion protein genotype. Taken together, the results from this study provide a more complete description of PrPSc species occurring in CJD brains and contribute to a fuller understanding of the agents and the disease processes involved in humans.
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Betmouni, Samar. "Inflammatory response in a mouse model of scrapie." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361753.
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Ironside, James Wilson. "Neuropathology and molecular biology of iatrogenic Creutzfeldt-Jakob disease in UK human growth hormone recipients." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28933.
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Creutzfeldt-Jakob disease (CJD) is the commonest form of human prion disease and occurs in sporadic, genetic and acquired forms. The causative agents (prions) appear to be composed entirely of a modified host protein, the prion protein, which undergoes misfolding to a disease-associated isoform closely associated with infectivity that is resistant to conventional methods of decontamination. Prions can be transmitted from one individual to another by medical and surgical procedures, resulting in iatrogenic CJD (iCJD). The commonest cause of iCJD is the inoculation of cadaveric pituitary-derived human growth hormone (hGH) to treat growth hormone deficiency in children; this form of treatment was abandoned in 1985 after the first UK case of iCJD in a hGH recipient was identified. Seventy-eight cases of iCJD have since occurred in the UK cohort of 1849 hGH recipients, including a case in 2016. This thesis describes a comprehensive tissue-based and molecular genetic analysis of the largest series (35 cases) of UK hGH-iCJD cases reported to date, including in vitro kinetic molecular modelling of genotypic factors influencing prion transmission. The results show that the polymorphism at codon 129 of the prion protein gene strongly influences the disease incubation period in hGH-iCJD (from 7.8-32.3 years in this series) and interacts with the infectious prion strain to govern the molecular and pathological characteristics of iCJD. The findings are consistent with the hypothesis that the UK hGH-iCJD epidemic resulted from transmission of the V2 human prion strain, which is found in the second most common form of sporadic CJD. The investigation also found accumulation of the amyloid beta (Aβ) protein associated with Alzheimer’s disease (AD) in the brains and cerebral blood vessels in 18/35 hGH-iCJD patients and 5/12 control patients who had been treated with hGH, but died from causes other than iCJD. In contrast, Aβ accumulation was markedly less prevalent in age-matched patients who died from sporadic CJD (1/15 cases) and variant CJD (2/33 cases). These results are consistent with the hypothesis that Aβ, which can accumulate in the pituitary gland, was present in the inoculated hGH preparations and seeded into the brains of around 50% of all hGH recipients, producing AD-like neuropathology and cerebral amyloid angiopathy (CAA). This provides further evidence of the prion-like properties of Aβ and gives insight into the potential for possible transmission of AD/CAA. It is uncertain whether any Aβ seeding within the brains of surviving patients in the UK hGH recipient cohort will ultimately result in clinical AD; however, the CAA in these patients may be complicated by intracerebral haemorrhage resulting from rupture of the blood vessels damaged by Aβ accumulation within their walls.
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Douet, Jean-Yves. "Perméabilité des barrières de transmission et évaluation du risque iatrogène associé aux agents responsables des Encéphalopathies Spongiformes Transmissibles." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0033/document.
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Les Encéphalopathies Spongiformes transmissibles (EST) sont des maladies neurodégénératives fatales caractérisées par l’accumulation d’un conformère anormal (PrPSc) d’une protéine de l’hôte (PrP). Chez l’homme, plusieurs centaines de cas de transmissions iatrogènes de la maladie de Creutzfeldt Jakob (MCJ) ont été identifiées, notamment chez des patients ayant fait l’objetd’ une greffe de dure-mère, de cornée ou des injections d’hormones de croissance extractives. Plus récemment, plusieurs cas du variant de la maladie de Creutzfeldt Jakob (vMCJ) ont été observés chez des patients transfusés avec des produits sanguins issus de donneurs en incubation de la maladie. D’un point de vue sanitaire, l’évaluation du risque de contamination interindividuelle par des tissus ou des fluides biologiques issus de patients atteints représente un enjeu important en matière de santé publique. La première partie de notre travail a consisté à comparer la sensibilité relative de modèles de souris transgéniques sur-exprimant la PrP à celle de l’hôte conventionnel exprimant la même séquence. Les résultats obtenus ont validé le concept d’une absence d’impact du niveau d’expression de la PrP ou du fond génétique de l’hôte sur la sensibilité finale du modèle à l’infection. A l’aide de ces modèles de souris transgéniques, nous avons alors mesuré les niveaux d’infectiosité dans le sang de patients atteints de différentes formes d’’EST. Chez un patient atteint de vMCJ, nous avons mis en évidence de faibles niveaux d’infectiosité dans les concentrés de globules rouges, les leucocytes et le plasma. Nous avons également pu détecter de l’infectiosité dans le plasma issu de 2 patients atteints de sMCJ sur 4 testés. Parallèlement à ces expériences, nous avons démontré dans un modèle expérimental d’infection chez le mouton, que l’administration de 104 à 105 leucocytes suffisent à transmettre par voire transfusionnelle la maladie. Ces résultats soulignent l’intérêt et les limites de la leuco-déplétion appliquée de manière standard en médicine transfusionnelle, pour limiter les risques de transmission du vMCJ. Enfin, nous avons testé la capacité de différents outils in vitro à détecter la présence des Prions dans le sang<br>Transmissible spongiform encephalopathies (TSE) are fatal neurodegenerative disorders occurring in a wide spectrum of animals. They are characterized by accumulation of abnormally folded conformers (PrPSc) derived from normal cellular PrP protein (PrP) of the host. In human, many iatrogenic transmissions of Creutzfeldt Jakob disease (CJD) have been reported after dura mater graft, corneal graft or extractive growth hormone injections, prepared from affected donors. More recently, several cases of vCJD transmissions were reported in individuals that were transfused with blood from asymptomatic donors that subsequently developed vCJD. Risk assessment of interindividual transmission with contaminated tissues or body fluids remains a major public health issue. In a first part, we validated the final pertinence of infectious titers as measured in mice overexpressing PrP to the risk of transmitting the disease in the natural host species. In a second time, we used this model to evaluate the presence of infectivity in blood from TSE affected patients. We were able to detect the presence of infectivity in erythrocytes, leukocytes, and plasma of 1 person with vCJD and in the plasma of 2 out of 4 persons whose tests were positive for sporadic CJD. We then demonstrated in a sheep TSE model, that intravenous administration of 104 to 105 leucocytes was sufficient to cause disease in recipient sheep, underlying the efficacy and potential limits of leuko-reduction processes that are currently applied in transfusion medicine to mitigate the TSE transmission risk. Finally, using the same model, we tested different in vitro methods to detect prions in blood
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De, Silva Rajith Nilantha. "A correlative study of the clinical, pathological and molecular biological features of Creutzfeldt-Jakob disease." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/27887.
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A systematic study of all patients with pathologically or electrophysiologically confirmed Creutzfeld-Jakob disease (CJD) referred to the U.K. national surveillance unit between May, 1990 and April, 1994 has been undertaken. The numbers of sporadic, familial and iatrogenic cases were 144, 14 and 12 respectively. Sporadic CJD cases had a median age at presentation of 65 years, and a median disease duration of 4 months. Familial cases (associated with mutations of the open reading frame of the prion protein gene, PRNP ORF) presented 10 years earlier and had disease durations which were twice as long. Clinical characteristics at different stages of illness were identified. At presentation, around 40% of sporadic cases had some aspect of cognitive impairment in isolation, 30% had cerebellar dysfunction in isolation, 10% had a combination of cognitive and cerebellar dysfunction, and 10% had occipital blindness. Alternative modes of presentation were unusual (<10%), and the forms of CJD characterised by pure progressive cerebellar ataxia was rare (<4%). The clinical characteristics of the sporadic and the grouped familial cases did not differ. Characteristic electroencephalographic findings were present in 35% of pathologically confirmed cases. Familial cases were more likely to have a family history of (non-specific) neurodegeneration. Iatrogenic cases in whom the agent was inoculated outside the central nervous system were shown to have a different clinical profile early in the illness from sporadic cases. The clinical characteristics of the sporadic and familial cases were compared at different stages of illness with those of a group of patients with suspected CJD whose neuropathological examinations had revealed an alternative neurodegenerative process (non-CJD). The relative sensitivities and specificities of the standardised criteria used in the clinical evaluation of suspect CJD cases were high, with the exception of "neurogenic muscle wasting". The non-CJD group had a disease duration that was four times as long as the sporadic CJD cases.
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Cooper, J. D. "Statistical modelling of UK dietary exposure to bovine spongiform encephalopathy and variant Creutzfeldt-Jakob disease." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597975.
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Surprisingly, few attempts have been made to ascertain the data required to quantify human dietary exposure to BSE. After investigations, the primary sources of exposure were assumed to have been through the consumption of burgers, sausages and other meat products containing beef mechanically recovered meat (MRM) and head meat, which were potentially contaminated respectively with BSE infected spinal cord and dorsal root ganglia, and brain. Risk analyses for contamination are conducted and meat product destination and calendar year production are estimated using information collected from reports, interviews and the BSE Inquiry. Subsequently, calendar year exposures to BSE in burgers, sausages and other meat products are simulated and dietary data used to partition exposures by the age-group and gender of their consumers. Simulation models are constructed to predict vCJD incidence using the dietary exposure intensities to BSE. Despite incubation period uncertainty, overall low predictions of vCJD incidence within the subpopulation of the UK with the affected genotype are made. According to the best fitting models, almost two-thirds of predicted vCJD patients in 2001-2005 are expected to be in the post-1969 birth cohort, whose vCJD incidence is predicted to peak in this calendar period and to outnumber (about 1.5 times more onsets) those in the 1940 to 1969 birth cohort. Very few onsets are predicted to occur after 2010 in the post-1969 birth cohort. In contrast, for the 1940 to 1969 birth cohort, almost half of onsets are predicted to occur after 2010. About three-fifths of vCJD patients are expected to be male. The dietary exposure intensities to BSE show that the age distribution of observed vCJD patients can only arise if younger individuals have a shorter incubation period and/or more susceptible to infection. There is remarkable similarity between the age distribution and gender of simulated and observed vCJD patients, which supports the assumptions made about the primary sources of human dietary exposure to BSE.
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Nakatani, Eiji. "Specific clinical signs and symptoms are predictive of clinical course in sporadic Creutzfeldt-Jakob disease." Kyoto University, 2016. http://hdl.handle.net/2433/217720.
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Cooper, Sarah. "The clinical features and diagnosis of sporadic Creutzfeldt-Jakob disease in the United Kingdom, 1990-2002." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/26411.
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Background: Sporadic Creutzfeldt-Jakob disease (sCJD) is an invariably fatal spongiform encephalopathy that has a worldwide incidence of approximately 1/1,000000 per year. Prospective surveillance has been in place in the UK since 1990, coordinated by the National CJD Surveillance Unit (NCJDSU). Accurate surveillance of CJD is important not only in detecting changes in patterns of disease and predicting trends but also in instituting protective public health measures. Aims of the study: To define circumstances where making a clinical diagnosis of sCJD is potentially problematic. To explore ways of improving diagnostic accuracy and enhancing surveillance in these settings. Methodology: Clinically "atypical" cases of sCJD were defined according to specific criteria (young, long duration, certain focal features at onset) and identified by retrospective case-file review of all 485 pathologically-proven cases (1990-2002). Comparisons were made with a consecutively selected "Core group" of "typical" sCJD (n=133). Cases identified only at autopsy, cases finally classified as "Possible sCJD" (according to internationally agreed criteria) and initially suspect but pathologically proven non-cases were also identified and analysed. Results and conclusions: Twenty four per cent of all pathologicallly confirmed sCJD cases were "atypical". For each "atypical" subgroup, relatively distinct phenotypic characteristics were identified when compared with the Core group. Long duration cases were associated with early depression and personality change, more psychiatric features and infrequent cerebellar or extrapyramidal features. Young cases had less ataxia at onset and more psychiatric symptoms and involuntary movements. Cases presenting with predominantly cerebellar features were associated with a higher prevalence of visual disturbance and sensory symptoms and a longer illness duration. Those with a pure visual onset had a shorter duration with less cerebellar or extrapyramidal features. Amongst "atypical" cases (with the exception of pure visual onset cases) the electroencephalogram was diagnostically less sensitive and where positive was associated with short disease duration and increased age at onset. Visual onset cases were associated with genotype MM at codon 129 of the prion protein gene. Nineteen per cent of sCJD cases were referred after autopsy, of these about one third were not diagnosed whilst alive. Alzheimer's disease (AD) was the most likely alternative diagnosis in pathologically proven non-cases except when disease duration was less than six months, where paraneoplastic/neoplastic disease was commonest. Diagnostic accuracy is likely to improve with a greater understanding of the range of disease presentation, evolution and differential diagnoses along with the targeted use of diagnostic tests. The referral of unusual cases should be encouraged. In view of the declining autopsy rates in the U.K. it is particularly important that accuracy in clinical diagnosis is pursued.
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Correia, Susana Margarida da Silva. "Altered regulatory response of Rab7a and Rab9 in MM1 and VV2 subtype of Creutzfeldt-Jakob disease." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15769.
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Mestrado em Biologia Molecular e Celular<br>The present study was undertaken to identify proteins interacting with PrPC that could provide new insights into its physiological functions and pathological role. We performed a target search for lysosomal network protein, Rab7a and Rab9, in frontal cortex and cerebellum of human brain from patients with sCJD-MM1 and sCJD-VV2. The intracellular level of Rab7a was increased significantly, when compared with healthy age-matched control. Interactions of PrPC and Rab7a/Rab9 were further investigated by using confocal laser scanning microscopy. Immunofluorescence results suggested potential interactions of Rab7a and PrPC. siRNA against the Rab7a gene was used to knockdown the expression of Rab7a protein in primary cell culture of cortical neurons from wild type mice. This depleted Rab7a resulted an impairment of PrPC trafficking leading to an accumulation of PrPC in the endocytosis pathway. Furthermore, interactions of Tau and Rab7a were investigated by using western blot analysis and confocal laser scanning microscopy. Cell cultures of cortex of wildtype mice were treated with siRNA-Tau, siRNA-Rab7 and control siRNA followed by immunofluorescence. The results of immunofluorescence suggested potential interaction of Tau and Rab7a. Cells lines treated with siRNA-Tau, the intracellular levels of Rab7a and Rab9 significantly increases and their localization is also modified. When we transfected this cells lines with siRNA-rab7a the accumulation of Tau decreases in cytosolic region and their localization was also modified when compared with control cells. In conclusion, this study may help to understand and characterize the subtype specific disease progression in CJD cases. Furthermore, it could be a step ahead to development of new treatment strategies for diseases subtype specific manner.<br>O presente estudo foi levado a cabo com o intuito de identificar possíveis proteínas que interajam com PrPC que possam fornecer novos conhecimentos sobre as suas funções fisiológicas assim como no papel patológico. O presente estudo incidiu na investigação dos níveis das proteínas endossomais Rab7a e Rab9 em amostras do córtex frontal e cerebelo de pacientes diagnosticados com sCJD-MM1 e sCJD-VV2. Observamos um aumento significativo dos níveis intracelulares do Rab7a em pacientes diagnosticados com sCJD-MM1 e sCJD-VV2 quando comparadas com amostras de pacientes na mesma faixa etária sem a doença (controlo). As interações entre PrPC e as proteínas Rab7a e Rab9 foram posteriormente estudadas com o auxílio à microscopia confocal. Os resultados da imunofluorescência sugeriram potenciais interações entre as proteínas Rab7a com o PrPC. O siRNA-Rab7 foi usado para diminuir a expressão da proteína Rab7a (“Knockdown”) na cultura primária de células do córtex de ratos saudáveis. Na cultura de células do córtex tratadas com o siRNA-Rab7, foi observado um emparelhamento da via endocítica. Seguidamente investigamos possíveis interações da proteína Tau com a proteína Rab7a, recorrendo ao western blot e a microscopia confocal. Culturas de células do córtex de ratos saudáveis foram tratadas com siRNA-Tau, siRNA-Rab7a e siRNA. Os resultados da imunofluorescência das diferentes culturas celulares sugeriram uma potencial interação entre as proteínas Tau e Rab7a. Nas linhas celulares tratadas com siRNA-Tau os níveis intracelulares das proteínas Rab7a e Rab9 aumentaram significativamente, assim como, foi também observada a alteração da sua localização. Nas células tratadas com siRNA-Rab7a observamos uma diminuição da acumulação da proteína Tau na região citosólica. Em conclusão, este trabalho pode ajudar a perceber e a caracterizar a progressão da doença nos subtipos específicos, no caso de sCJD. Contudo, este trabalho poderá ser também um passo à frente para o desenvolvimento de novas estratégias terapêuticas para os subtipos sCJD-MM1 e sCJD-VV2.
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Chohan, Gurjit Kaur. "A correlative study of the clinical, pathological and biochemical features of sporadic Creutzfeldt-Jakob Disease, 2000-2006." Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/28449.
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Historically various CJD syndromes have been described with a spectrum of clinical presentations. Sporadic CJD (sCJD) is the most common form of human transmissible spongiform encephalopathy (TSE) and is characterised by accumulation of pathological prion protein (PrP) in the central nervous tissue. Classification criteria have changed with the advent of novel diagnostic tests over the last decade. The subclassification according to the codon 129 genotype and prion protein (PrP) type in the brain has led to the identification of six sCJD subtypes, but whether different phenotypes are related to distinct infectious agent strains remains unclear. In order to assess clinical phenotype in detail, four hundred and fourteen cases of sCJD referred to the NCJDSU and classified using the Rotterdam Criteria (1998) were retrospectively analysed (2000-2006). Seventy-four non-cases (1998-2008) were included for comparative analyses. The number of referrals seen has remained relatively uniform with necropsy performed on 70% of suspect cases. The clinical phenotype is less well defined than previously postulated with marked overlap of clinical symptoms and signs independent of PrP[superscript sc] subtype, PRNP genotype and age of onset. In particular the MM1 and MV1 subtypes are not as clinically matched as previously proposed, with the suggestion that these are two distinct forms. The early development of symptoms and signs however favours a diagnosis of sCJD compared with non-cases and may be a potential diagnostic indicator for sCJD. The utility of investigative tests in sCJD, including the EEG and CSF 14-3-3 have been validated. The additional role of the brain MRI, particularly in atypical subtypes, is also demonstrated. This thesis demonstrates that the current WHO diagnostic criteria for sCJD are of value. However, the inclusion of the results of brain MRI and the time to onset of neurological signs and symptoms may improve diagnostic accuracy and allow identification of atypical phenotypes.
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Peckeu, Laurène. "Physiopathologie des formes infectieuses de maladies à prions humaines : étude des formes iatrogènes secondaires à un traitement par l'hormone de croissance." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066583/document.
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Les maladies à prions sont des maladies neurodégénératives et transmissibles. Elles sont à l'origine de formes infectieuses comme la maladie de Creutzfeldt-Jakob iatrogène secondaire à un traitement par hormone de croissance d'origine humaine (MCJ post-hGH). La compréhension des facteurs gouvernant la physiopathologie de ces formes demeure parcellaire. Notre objectif a été de les étudier en analysant la cohorte des patients français exposés à l'hGH. Les analyses épidémiologiques, ont montré, à partir de données quantifiées, pour la première fois chez l'homme, une relation entre la dose d'exposition et le risque de développer la maladie d'une part et la durée de la période d'incubation d'autre part. La modélisation de la période d'incubation, a permis d'estimer que 95% des cas sont déjà apparus et d'évaluer l'influence du polymorphisme au codon 129 du gène codant la protéine prion sur la période d'incubation. L'étude descriptive a montré des similarités clinico-pathologiques entre tous les cas de maladies à prion humaines par contamination périphérique laissant supposer un rôle important de la voie d'exposition. Les expériences de transmission à la souris transgénique devraient permettre de valider les hypothèses que nous avons émises sur l'identité des souches présentes dans les lots contaminés. Ce travail a donc permis de mieux caractériser les facteurs impliqués dans la transmission des maladies à prions chez l'homme et de fournir un cadre méthodologique et des informations qui pourraient être utiles pour évaluer le risque de transmission potentielle des autres protéinopathies du système nerveux central pour lesquelles un mécanisme " prion like " a été proposé<br>Prion diseases are fatal and transmissible neurodegenerative disorders. Infectious forms include iatrogenic Creutzfeldt-Jakob disease after human cadaver-sourced growth hormone treatment (hGH-iCJD). Our understanding of the factors governing the pathophysiology of infection, upon exposure to an exogenous prion, remains very limited in humans. The aim of this study was to better understand these phenomena using data from the French cohort of patients who were exposed to this at risk treatment. Using Cox hazards model, we provided the first epidemiological evidence of a relationship between dose of exposure and disease occurrence on one hand and incubation time on the other hand. Incubation period modelling by Weibull distribution estimated that 95% of the cases have already occurred. In a descriptive study, we showed that clinical and neuropathological features resembled other forms of infectious prion diseases after a peripheral contamination supporting a major role of the route of exposure. We also performed experimental transmission to transgenic mice expressing human PrP to test our hypotheses about the infecting prion strain that were transmitted to French hGH-iCJD patients. To conclude, we identified factors implicated in human prion transmission and provided a methodological frame and useful information that could help to evaluate the transmission risk associated with other brain proteinopathies such as Alzheimer and Parkinson’s diseases for which a prion-like mechanism has been proposed
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Gougerot, Alexianne. "Physiopathologie et thérapeutique des prions humains : une approche cellulaire." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066087/document.
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Les maladies à prions sont des pathologies neurodégénératives d’évolution fatale, transmissibles, pour lesquelles aucun traitement efficace n’existe. Elles associent sur le plan neuropathologique une spongiose, une gliose astrocytaire, une perte neuronale, et une accumulation de la forme anormalement repliée (PrPsc) de la protéine prion cellulaire codée par l’hôte. Certaines formes de cette maladie sont associées à une tauopathie et présentent des lésions neuropathologiques similaires à celles retrouvées dans la maladie d’Alzheimer (MA).Nous avons utilisé un modèle de cultures primaires de neurones afin d’explorer d’une part la relation entre la protéine prion et la physiopathologie de la protéine tau, et d’étudier d’autre part la propagation de souches humaines et l’effet de composés anti-prions sur cette propagation. Nos résultats indiquent que l’hyperphosphorylation de tau en réponse à l’exposition de PrP recombinantes est mutation dépendante, conformation dépendante, partiellement dépendante de la PrPc et est médiée par la kinase PDK1. Nous avons aussi démontré pour la première fois que la propagation d’isolats humains de maladie de Creutzfeldt-Jakob est possible dans un modèle in vitro et permet une évaluation rapide de l’efficacité de composés anti-prions, confirmée in vivo. Ces travaux ont permis de mieux caractériser la relation protéine amyloïde-physiopathologie de tau, d’ouvrir des perspectives de recherche dans la compréhension des mécanismes impliqués dans la MA, et d’apporter un modèle unique permettant d’évaluer rapidement les effets de molécules anti-prions vis-à-vis des souches les plus pertinentes, dans une stratégie de repositionnement thérapeutique<br>Prion diseases are fatal transmissible neurodegenerative disorders, with no effective treatment. Brain lesions include neuronal vacuolization, astrogliosis, neuronal loss and the accumulation of PrPSc, an abnormal isoform of the host-encoded cellular prion protein (PrPc). Some forms of prion diseases are associated with tau fibrillar pathology similar to that observed in Alzheimer’s disease except that Abeta peptides are replaced by PrPsc. Here we used a primary neuronal cultures to first explore the interplay between the formation of prion protein assemblies and the occurrence of tau pathology, and secondly to evaluate in vitro human strain propagation and the efficiency of some antiprion compounds towards human prions. We showed that tau hyperphosphorylation in response to recombinant PrPs exposition was mutation-dependent, conformation-dependent and varied with the PrPc expression level of exposed neurons. This effect was mediated by PDK1 kinase. We also demonstrated for the first time that human prion isolates could propagate in an in vitro model. This model was also useful to evaluate the efficacy of antiprion compounds that was further validated in vivo. Our results help us to better understand the amyloid protein-tau physiopathology interplay and provide a useful and unique tool for fast evaluation of therapeutic compounds active against human prion strains in a repositioning strategy in such rare but devastating diseases
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Ritchie, Diane Louise. "Characterisation of the agent strain in sporadic and variant Creutzfeldt-Jakob disease by transmission to wild-type mice." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/9563.
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Transmissible spongiform encephalopathy (TSE) strains are defined by their biological properties on transmission to wild-type mice, specifically by their characteristic incubation periods and patterns of vacuolar pathology (‘lesion profiles’) in the brain. Whilst a single TSE strain has been identified in variant Creutzfeldt-Jakob disease (vCJD), the phenotypic heterogeneity observed in sporadic CJD (sCJD) implies the existence of multiple strains of agent. These distinct strains are proposed to be enciphered by the different conformers of abnormal prion protein (PrP), recognised as different protease resistant PrP (PrPres) types by Western blotting (type 1 or type 2) and are thought to be substantially influenced by the different prion protein gene (PRNP) codon 129 polymorphism (MM, MV and VV). To test the relationship between disease phenotype and agent strain, this study carried out a full characterisation of the sCJD agent by primary transmission of brain tissue from 27 sCJD cases (comprising all six possible combinations of PRNP codon 129 genotype and PrPres type) in panels of wild-type mice using the standard strain typing properties of incubation period and lesion profiles, plus a full analysis of PrP in the mouse brain and the PrPres molecular subtypes present. Results were directly compared with the transmission characteristics of brain tissue from 10 vCJD cases. The characterisation of the agent strain in sCJD and vCJD was extended to include analysis of subsequent mouse-to-mouse passages. In an additional investigation, wild-type mice were experimentally challenged with a wide-range of lymphoid tissues, neural tissues and biological fluids from vCJD and sCJD patients in order to investigate the extent of peripheral involvement in CJD and to determine whether the agent is subject to any tissue-specific modifications. Analysis of all 27 sCJD sources demonstrated the existence of two strains of agent, one associated with the MM1/MV1 subgroups and the other associated with the MM2 subgroup, which could be distinguished by their transmission properties in the mice. The lack of transmission in mice challenged with VV1, MV2 and VV2 tissues provided evidence of at least one further sCJD strain. In contrast, all 10 vCJD sources resulted in consistent incubation periods and lesion profiles, suggesting that all 10 patients investigated were infected with the same strain of agent. Overall, the observation that PrPres type in sCJD and vCJD was maintained on transmission is consistent with the proposition that PrPres type plays a role in enciphering strain-specific information. Experimental transmissions from peripheral tissues extended the evidence for a peripheral infection in vCJD. However, comparison of incubation periods and lesion profiles from transmission of brain and peripheral tissues showed no evidence of tissue-specific modification in the biological properties of the agent. Furthermore, the detection of low levels of infectivity in a sCJD buffy coat sample provides supporting evidence for a peripheral involvement in sCJD. This study highlights the complex relationship between disease phenotype, PRNP codon 129 genotype, PrPres type and agent strain in sCJD and vCJD. Overall, this study confirms that multiple strains of agent are associated with sCJD, some of which successfully propagate in wild-type mice but none of which are identical to the agent responsible for vCJD. Importantly, the sCJD strains identified here by their biological properties partially correlated with the current sub-classification system for sCJD which is based on the clinical and pathological phenotype of the disease.
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Briddell, Brian L. "Creutzfeld-Jakob disease : a synthesis of current literature for health care providers." Honors in the Major Thesis, University of Central Florida, 1998. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/23.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.<br>Bachelors<br>Health and Public Affairs<br>Nursing
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Harding, Mark R. "Analysis of post-mortem magnetic resonance image data of the human brain for the diagnosis of Creutzfeldt-Jakob disease." Thesis, University of Edinburgh, 2002. http://hdl.handle.net/1842/10934.
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Despite its generally low annual global incidence rate, Creutzfeldt-Jakob disease (CJD) has become a subject of considerable interest in recent years. This is due to concerns that there may be a possible causitive link with Bovine Spongiform Encephalopathy and that this may forewarn of a future epidemic of CJD in Humans. Despite recent discoveries of CJD related abnormalites in lymph-node tissues, in-vivo diagnosis of CJD is difficult and relies on a series of clinical tests and observations to provide a probabilistic diagnosis of the disease. The confirmed diagnosis is currently only obtainable via biopsy or post-mortem histology. Medical imaging, specifically Magnetic Resonance Imaging (MRI), may offer a potential in-vivo diagnostic aid due to the reported presence of observable abnormalities in the MRI of CJD patients. To date research in this field has been hampered by a general lack of clinical data and the published work has been forced to consider exclusively the results of in-vivo MRI measurements. The National Creutzfeldt-Jakob disease Surveillance Unit in Edinburgh, U.K. has compiled a large and unique MRI dataset of post-mortem images of the Human brain from all deceased patients whose clinical presentation suggested CJD. Post-mortem confirmation of diagnosis is also held. This thesis describes the findings of an investigation to evaluate the potential of this post-mortem MRI dataset to provide diagnostically useful information in the task of assessing the CJD status of a patient. It uses image intensity analysis based tests to provide results whose performance may be compared to the accepted radiological methods of visual inspection of hard-copy data. By plotting distributions of statistical intensity metrics for specific regions of interest, known to have shown abnormalities in in-vivo MRI cases, the relationship between the MR image intensity for these regions and the ultimate patient diagnosis was determined. Additional work investigating methods for determining shape and intensity symmetry, which can help differentiate between disorders, is also described. Through the analysis of specific brain regions, it is shown that the MRI tests described display sensitivity to the condition of CJD. Future work is needed to investigate whether equivalent results can be produced by similar tests on in-vivo MRI data, when this becomes available. This could potentially offer a useful non-invasive pre-mortem test for CJD that would aid the task of clinical patient assessment.
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McCormack, James E. "Characterisation of regulatory regions of the PRNP gene and their effect on susceptibility to sporadic and variant Creutzfeldt-Jakob Disease." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/24929.
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Based on analysis of PrP gene regulatory regions in other species, 4.8 Kb of human genomic sequence containing 1.5Kb of upstream sequence the first exon and 3.1Kb of intron was cloned from a human genomic lambda library into a CAT reporter gene. Transient transfections in human neuroblastoma cells of this construct and of nested deletions of this construct identified two regulatory regions, one between -43 and -9 bases upstream of the transcription initiation site and one within the intron between +292 and +622 basepairs. Having identified regulatory regions in neuroblastoma cells the effect of the two regulatory regions on expression <i>in vivo</i> was examined by making three constructs where expression of a LacZ reporter gene was driven by the 4.8Kb human fragment, the upstream and exon sequence or the exon and intron sequence. A construct which contained 3.4Kb of equivalent murine sequence was used as a control. Although all four constructs were successfully injected into fertilised eggs giving rise to transgenic embryos and adults, no lacZ expression was detected suggesting that additional sequences may be required for full expression of <i>PRNP.</i> The upstream and intronic regions were sequenced in sCJD, vCJD and control individuals to determine if any polymorphism or mutations exist in the regulatory regions which cause or affect susceptibly to either form of CJD. Three polymorphisms were identified, a C to G transversion at position - 101 relative to the start of exon one was found at an allele frequency of 13% in control individuals, a G to C transversion at +310 found at a frequency of 6% in controls and a T to C transition at position +385 found at a frequency of 5% in controls. Analysis of the frequency of these polymorphisms in CJD patients and controls showed that the - 101G and +310C alleles each independently increase an individual's risk of developing sporadic CJD. The effect of -101G allele was strongest in PrP ORF codon 129 methionine homozygotes even when the linkage between -101G and codon 129 methionine was accounted for. the +385C allele increased susceptibility to vCJD but this was not significant.
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Klotz, Daniel Martin, and Rose Sarah Penfold. "Low mood, visual hallucinations, and falls – heralding the onset of rapidly progressive probable sporadic Creutzfeldt–Jakob disease in a 73-year old: a case report." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-236920.
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Background
Creutzfeldt–Jakob disease is a rare and rapidly fatal neurodegenerative disease. Since clinicians may see only very few cases during their professional career, it is important to be familiar with the clinical presentation and progression, to perform appropriate investigations, and allow for quick diagnosis.
Case presentation
A 73-year-old British Caucasian woman presented with acute confusion of 2 weeks’ duration on a background of low mood following a recent bereavement. Her symptoms included behavioral change, visual hallucinations, vertigo, and recent falls. She was mildly confused, with left-sided hyperreflexia, a wide-based gait, and intention tremor in her left upper limb. Initial blood tests, computed tomography, and magnetic resonance imaging of her brain showed no significant abnormality. Following admission, she had rapid cognitive decline and developed florid and progressive neurological signs; a diagnosis of prion disease was suspected. A lumbar puncture was performed; cerebrospinal fluid was positive for 14–3-3 protein, real-time quaking-induced conversion, and raised levels of s-100b proteins were detected. An electroencephalogram showed bilateral periodic triphasic waves on a slow background. The diagnosis of probable Creutzfeldt–Jakob disease was made.
Conclusions
This case report highlights key features in the initial presentation and clinical development of a rare but invariably rapidly progressive and fatal disease. It emphasizes the importance of considering a unifying diagnosis for multifaceted clinical presentations. Although it is very rare, Creutzfeldt–Jakob disease should be considered a diagnosis for a mixed neuropsychiatric presentation, particularly with rapid progressive cognitive decline and development of neurological signs. However, to avoid overlooking early signal change on magnetic resonance imaging, it is important to take diffusion-weighted magnetic resonance imaging for all patients with neuropsychological symptoms. Importantly, early diagnosis also ensures the arrangement of suitable contamination control measures to minimize the risk of infection to health care professionals and other patients.
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Barria, Matus Marcelo Alejandro. "Modelling human prion replication in cell-free systems." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/10025.
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One of the key molecular events in the transmissible spongiform encephalopathies or prion diseases is the conformational conversion of the cellular prion protein PrPC into the misfolded and pathogenic isoform, PrPSc. Prion diseases are fatal neurodegenerative conditions affecting humans and other animal species, which present with diverse clinical and neuropathological phenotypes. In humans, prion diseases can occur as sporadic, familial or acquired forms. Sporadic Creutzfeldt–Jakob disease (sCJD) accounts for the majority of cases. The current classification system of human prion diseases recognizes several distinct clinico-pathological entities including sCJD, variant Creutzfeldt-Jakob disease (vCJD), Gerstmann–Straussler–Scheinker syndrome, fatal familial insomnia and variably protease-sensitive proteinopathy. Prion protein gene (PRNP) mutations and polymorphisms, and PrPSc types have a profound effect on these clinico-pathological phenotypes. Prion diseases of sheep and goats, cattle, and cervids are all actual animal health problems and present potential risks to human health. Thus far the only known zoonotic prion disease is bovine spongiform encephalopathy, which has resulted in vCJD in humans. The recognition of new forms of prion diseases in animal and humans has generated increased awareness of the animal and public health risks associated with prion disease. However the mechanisms involved in prion replication, transmission, and neurodegeneration remain poorly understood. This thesis uses in vitro PrP conversion assays (protein misfolding cyclic amplification and real time quaking-induced conversion) to model different aspects of human prion replication: Molecular susceptibility, genetic compatibility, spontaneous formation and the effect of molecules that might enhance or prevent conversion were each investigated in order to obtain a better understanding of the molecular mechanism of the prion replication. I have addressed the hypothesis that the major determinant factors in prion disease pathogenesis (PRNP genetics, PrPSc types and species barriers) are intrinsic to the prion protein conversion process and their effects can be faithfully recapitulated by in vitro conversion assays. The results shows that in vitro conversion assays used in this thesis can model the combined effects of different PrP type and genotypes, can replicate aspects of cross-species transmission potential and provide information about molecular barrier to zoonotic transmission, can model de novo PrPSc formation, and can assess the potential impact of chaperones on conversion of the human prion protein. In summary, this work provides evidence that the origin, propagation and transmission of prions can be meaningfully investigated in cell-free systems.
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Aouba, Achille Eric. "Politiques et choix des produits plasmatiques ou recombinants en hémophilie : enjeux sécuritaires et déterminants institutionnels, médicaux et psycho-sociaux." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05D004.
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Introduction et problématiques: Les politiques et choix des produits plasmatiques (PP) ou recombinants (PR) en hémophilie divergent selon les pays en dépit de recommandations internationales consensuelles. A la différence d'autres pays, la politique française en ce sens ne fait aucune priorité de choix entre les PP versus les PR en dépit de l'avènement de variante (v) de la maladie de Creutzfeldt-Jakob (MCJ) dont le risque transfusionnel affecté à ces premiers est jugé être infinitésimal. L'adhésion des soignants et des patients à cette politique ainsi que les répercussions psychologiques des retraits de lots de PP pour le risque de vMCJ sur ces derniers, sont inconnues et suscitent des questions éthiques. Méthodologie: Des enquêtes mono et multicentriques ont été menées auprès de patients et médecins français afin d'évaluer leurs sentiments envers la politique de maintien sans restriction des PP et celle de leurs procédures de retrait de lots. Une discussion des problématiques éthiques inhérentes est conduite à partir des rapports des expertises scientifiques et de nos propres données. Résultats: L'analyse des politiques et choix des PP versus PR en hémophilie a permis d'identifier un modèle français aux côtés des trois modèles nord-américain, britannique et européen. Ce premier modèle apparaît être le moins astreignant alors que la France pointe à la haute deuxième place de la prévalence mondiale de la vMCJ après le Royaume Uni qui a tout simplement banni la prescription des PP pour les hémophiles, à la faveur des PR dénués de ce risque. Nous avons identifié nombre de tensions dans la prise en charge des patients et dans la gestion des risques de ces produits en France. Celles-ci sont principalement le fait de quatre problématiques qui correspondent à des paradoxes français de la politique de gestion de risque de ces produits, notamment: 1) multiplication injustifiée des procédures de retrait de lot de PP, essentiellement en rapport avec les formes sporadiques de la MCJ pourtant non transmissibles par ce biais. 2) absence de formalisation précise de l'organisation des procédures de retrait de lot dont les sources, les méthodes, les moyens et les délais de contact des médecins et leur relais aux patients sont divers et variés, ce qui témoigne d'une certaine improvisation et d'un cafouillage dans ce processus. 3) maintien sans restriction d'indication ni de source des PP. 4) information systématique traumatisante à posteriori des patients à l'occasion des retraits de lots pour ce risque très infime, au lieu d'une approche au cas par cas. Les problématiques éthiques induites sont: traumatisme psychologique rémanent des patients et leur famille à l'occasion de l'information, mal conduite et mal comprise, du risque de la vMCJ lors des procédures de retrait de lots de PP conduisant à leur switch massif pour des PR; inefficacité de ces procédures à éliminer les lots incriminés car souvent déjà consommés; diminution drastique, voire bannissement de la prescription des PP; vécu difficile et désapprobation majoritaire des médecins de la politique du maintien sans restriction des PP et des procédures de retrait de lot; faible respect des procédures de retrait de lots, appliquées de façon confuse et inégale; crise de confiance des patients et médecins envers cette politique; sentiments de conflits d'intérêts des autorités politiques en rapport avec un protectionnisme supposé de l'industrie nationale de fabrication des PP en l'absence de motifs solides à leur maintien sans restriction à des indications précises. Conclusion: Un recadrage institutionnel de procédures de retrait de PP en France apparait nécessaire, celles-ci étant majoritairement injustifiées car relatives aux formes sporadiques de la MCJ. La limitation de l'usage des PP à des indications spécifiques nécessite d'être discutée à l'heure de la grande disponibilité des PR. De larges enquêtes et réflexions aideraient aux futures orientations de la politique nationale<br>Introduction and issues: The policy and local choices of plasmatic (PP) or recombinant products (RP) in hemophilia vary according to the country, despite consensus international recommendations. In contrast to other countries, French policy in this context gives no priority in the choice between plasmatic and recombinant ones, despite the appearance of variant Creutzeldt-Jakob disease (vCJD) involving risks in transfusions, albeit miniscule, in the former. Caregivers and patient adherence to this policy and its likely psychological impact on them, are unknown and raise ethical questions. Methodology: Single- and multi-site surveys of French doctors and patients were carried out to evaluate their feelings about the French policy of unrestricted continued use of plasmatic products and their procedures of batch recall. A discussion of inherent ethical problems is conducted, based on reports of scientific expertise and our own data. Results: This analysis allowed a French model to be defined and compared to the North American, British, and European ones. This French model seems to be the least strict in terms of the use of PP, while France is in second place in terms of the worldwide prevalence of vCJD, just after U.K who have simply banned the prescription of these first products for hemophiliacs in favor of RP, which are risk-free. We identified many ethical tensions in the management of patients and in risk management of these products in France. These are mainly due to four issues that correspond to the paradoxes of French policy of hemophilia product risk management, including: 1) unjustified multiplication of recall procedures concerning batches of PP, primarily those related to sporadic forms of CJD even though incommunicable through it; 2) lack of accurate formalization concerning the organization of batch removal procedures, the sources, methods, means and time of contact for physicians and their patients that are very varied, reflecting some improvisations and a mess in the process; 3) maintaining of unrestricted indication and source of PP; 4) systematic retrospectively traumatic information for patients, especially during the batch recalls for this very small risk, rather than a case-by-case basis. The induced ethical issues are : residual psychological trauma for patients and their families on the occasion of information, poorly managed and poorly understood, the risk of vMCJ during batches removal procedures of PP leading to their massive switch RP ; ineffectiveness of these procedures to remove incriminated batches since they are often consumed; drastic reduction or even banishment of the prescription of PP; difficult experience and majority disapproval of physicians maintaining unrestricted PP and batch removal procedures; low respect for batch removal procedures, applied unevenly; crisis of confidence of patients and physicians concerning this policy; feelings of conflict of interest from political authorities in connection with an alleged protectionism of the domestic industry manufacturing PP in the absence of strong reasons to their retention without restriction to specific indications. Conclusion: An institutional reframing of PP recall in France appears to be necessary, these being mainly unjustified since relative to sporadic CJD forms. Restrictions on the use of PP at specific directions need to be discussed at this time of high availability of RP. Extensive surveys would help the future direction of national policy
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GALENO, Roberta. "Characterization of human TSE strains after passage in humanized transgenic mice." Doctoral thesis, Università degli Studi di Verona, 2010. http://hdl.handle.net/11562/343521.
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Le encefalopatie spongiformi trasmissibili (EST) sono un gruppo di patologie neurodegenerative invariabilmente letali che si manifestano sia negli esseri umani che negli animali, causate da un agente trasmissibile la cui natura è in via di definizione. Ciononostante, le caratteristiche distintive di ciascun ceppo infettivo possono essere evidenziate e confrontate mediante passaggio sperimentale in una medesima specie di animali da laboratorio.
Utilizzando questo approccio si è visto che il ceppo responsabile della variante di malattia di Creutzfeldt-Jakob (MCJv) umana è correlato direttamente all’encefalopatia spongiforme bovina e, grazie a questa acquisizione, sono state ottimizzate le misure profilattiche per bloccare la diffusione della malattia all’uomo. Questa osservazione ha dimostrato la possibilità di trasmissione zoonotica delle EST animali e ha spinto le autorità sanitare e la comunità scientifica a intensificare gli sforzi per definire le caratteristiche dei diversi ceppi naturali col fine ultimo di definire la loro storia epidemiologica, la loro virulenza e di comprendere eventuali correlazioni tra forme atipiche animali ed umane.
Argomento della tesi di dottorato è la caratterizzazione dei ceppi associati ad alcuni casi italiani atipici di Malattia di Creutzfeldt-Jakob sporadica (MCJs) mediante trasmissione in topi transgenici che esprimono la proteina prionica umana omozigote per metionina (MM), per valina (VV), o eterozigote (MV) al codone polimorfico 129.
I tre casi umani studiati, tutti con genotipo eterozigote in posizione 129 della proteina prionica, erano caratterizzati da particolari clinici inusuali (due di essi da esordio precoce, lunga durata della malattia e sintomi psichiatrici), o da un’inusuale biochimica (il terzo caso) a livello della proteina prionica patologica (assenza della forma ad alta glicosilazione).
Le linee di topi transgenici originate mediante la tecnica del “gene targeting” posseggono il gene della proteina prionica umana nella corretta posizione all’ interno del genoma murino regolato dai corretti controlli di espressione. Questa modifica ha consentito di valutare le caratteristiche del ceppo in modo più approfondito rispetto a quanto è possibile fare con topi wild-type, permettendo di studiare la suscettibilità dei diversi genotipi umani (129 MM, VV, o MV) ai singoli ceppi prionici.
I risultati hanno dimostrato che i primi due casi hanno trasmesso la patologia con elevata efficienza a tutti e tre i genotipi, con un tropismo particolare per i topi omozigoti per valina, che si ammalano con tempi inferiori del 50% rispetto agli altri genotipi. Il caso con glicosilazione difettiva ha mostrato bassissima patogenicità producendo malattia conclamata solo in alcuni dei topi omozigoti per valina.
Il confronto dell’efficienza di infezione (animali ammalati/inoculati), dei tempi di incubazione, e dei profili neuropatologici e biochimici per la proteina prionica patologica tra i nostri animali e quelli di letteratura (inoculati con altre forme di CJD) ha mostrato che i nostri due casi con caratteristiche cliniche atipiche sono associati ad un ceppo infettante già noto, mentre il caso con glicosilazione atipica sembra appartenere ad un ceppo assolutamente originale e mai riscontrato in precedenza. Indagini più approfondite su questo caso sono in corso per comprendere la sua diffusione, pericolosità e gli eventuali rapporti con forme animali.
Lo studio ha confermato il grande potenziale di queste linee transgeniche non solo per l’identificazione di nuovi ceppi che hanno un rischio infettivo sconosciuto per la popolazione, ma anche per indagare l’influenza del polimorfismo al codone 129 sulla suscettibilità dell’ospite e sul processo patologico delle malattie da prioni.<br>Transmissible Spongiform Encephalopathies (TSEs) are fatal neurodegenerative diseases affecting humans and animals caused by a transmissible agent whose nature is still under debate. In spite of this uncertainty, the distinctive features of each infectious strain can be highlighted and compared through the experimental passage in a given species of laboratory animals. By using this approach, it was discovered that the strain responsible for variant Creutzfeldt-Jakob disease (vCJD) is directly related to the bovine spongiform encephalopathy infectious strain, thus helping to improve prophylactic measures to stop the spread of the disease. This observation proved the possibility of zoonotic transmission of animal TSEs and stimulated health authorities and researchers to intensify their efforts for the definition of strain properties with the aim to define their epidemiological history, their virulence and to understand possible correlations between atypical human and animal forms.
The subject of my PhD thesis is the characterization of the strains associated to several atypical Italian cases of sporadic Creutzfeldt-Jakob Disease (sCJD) by the transmission in transgenic mice which express the human prion protein gene (PRNP) with three alternative genotypes at the polymorphic codon 129 (MM, MV, VV), the most recognised factor of susceptibility and pathological phenotype in sCJD. The three human cases analyzed, all heterozygous at position 129 of the prion protein, were characterized by unusual clinical signs (two of them, by an early onset, long duration of the disease and psychiatric symptoms), or by unusual biochemical properties for what concern the pathological prion protein (absence of the high glycosylated form).
The three lines of transgenic mice, engineered by “gene targeting” technique, posses the human prion protein gene in the correct position within murine genome, under the strict control of natural expression modifiers. This genetic modification allowed to evaluate the “strain” characteristics and to study the susceptibility of the different human genotypes (129 MM, MV, VV) to the single prion strains.
Results showed that the first two cases transmitted the disease to all three genotypes with an high efficiency, yet with a particular tropism towards the valine homozygous mice which were clinically sick with incubation times 50% shorter than mice expressing the other genotypes. The case with defective glycosylation displayed an exceedingly low attack rate, producing overt disease only in few, valine homozygous, mice.
When comparing the efficiency of infection (sick animals/inoculated), the incubation times and the neurophatological and biochemical profiles, between our animals and their counterparts in the literature expressing identical PRNP genotypes but injected with other forms of sCJD, we observed that the two cases with atypical clinical features are associated to an infectious strain already known, whilst the case with atypical glycosylation seems to belong to an absolutely original strain, never found before. Concerning the latter case, further investigations are in course with the aim to understand its spread, its danger and its possible connection with animal forms.
The study confirmed the relevant value of these transgenic lines, not only to identify new strains with an unknown pathogenic potential for humans, but also to investigate the influence of the polymorphic codon 129 on the host’s susceptibility and the pathological process of the prion diseases.
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Mantovani, S. "Modelli murini transgenici di malattie da prioni per lo studio del ruolo fisiopatologico della proteina prionica." Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150216.
Full textAbstract:
Inherited prion diseases are linked to mutations in the prion protein (PrP) gene that are thought to favor the conformational conversion of PrP into a pathogenic misfolded isoform. Each mutation is associated with a distinct disease phenotype, which is profoundly affected by the Met/Val polymorphism at codon 129 in the PrP gene.
The most clear example of the phenotypic heterogeneity determined by the Met/Val polymorphism is represented by fatal familial insomnia (FFI) and Creutzfeldt-Jakob disease (CJD178), two clinically and neuropathologically distinct diseases linked to the D178N mutation in the gene encoding PrP; D178N/M129 segregates with FFI, while D178N/V129 is associated with CJD.
We have engineered transgenic (Tg) mice to express mouse PrP (moPrP) homologues of the human D178N/V129 and D178N/M129 mutations. cDNAs encoding D177N/V128 and D177N/M128 moPrP were cloned under the moPrP promoter. After microinjection into fertilized eggs from C57BL/6J X CBA/J parental mice (random transgenesis), we identified Tg mice which were backcrossed to PrP
knockout (C57BL/6J/Prnp0/0) mice.
We have obtained vary Tg founders: carrying D177N/V128 or D177/M128 PrP. The Tg copy number of the founders was determined by quantitative PCR, and the expression level of Tg PrP in the brain of hemizygous mice was determined by quantitative Western blotting.
We found that all CJD mice expressing the transgene at a level higher than the physiological one develop motor dysfunction; mice expressing the FFI mutation showed motor abnormalities only when the expression of the transgene was higher than 1X.
We have analyzed biochemical characteristics of mutated PrPs finding that they are similar to those observed in humans carrying the homologous mutations.
Ultrastructural analysis showed enlarged ER in CJD neurons and an abnormal onion-shaped Golgi in the FFI neurons. This characteristic could be the basis of the phenotypic heterogeneity between CJD and FFI and will be an important feature to study. The transgenic mice, good models of the human pathologies, could be use as a tool to study the physiological role of PrP and to test possible therapeutical approaches.
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Fagge, Timothy James. "A study of normal and abnormal forms of prion protein in the peripheral blood and tissues of patients with variant Creutzfeldt-Jakob disease." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/29751.
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This thesis assesses the potential use of PrP<sup>c</sup> as a surrogate marker for CJD by an analysis of blood from vCJD patients, sCJD patients, non-CJD neurological controls and healthy adults. PrP<sup>c</sup> was measured by DELFIA and cell-associated PrP was measured by flow cytometry. These are differences in free and cell-associated PrP found in blood of CJD patients and control groups, some of which may be useful as surrogate markers of disease DELFIA analysis identified a significant reduction in the concentration of PrP<sup>c</sup> in the whole blood of vCJD and non-CJD neurological patients compared with healthy adults. A significant elevation was found in plasma PrP<sup>c</sup> in sCJD patients compared with healthy adults and neurological controls. Flow cytometry found no significant differences between groups in the expression of PrP on platelets and lymphocytes. Neurological controls show significantly less PrP on red cells than healthy adults. In addition the development of a DELFIA based test designed for the detection of the disease-associated PrP<sup>Sc</sup> in human peripheral blood is the other main focus of research studies detailed within this thesis. Sensitive assays have been developed using existing techniques allowing the detection of PrP<sup>Sc</sup> in the central nervous system and peripheral lymophoreticular tissues of patients with vCJD as validatory studies prior to application of these assays to patient blood samples. Atomic dielectric resonance spectroscopy analysis techniques have also been used to investigate potential differences in frequency and atomic resonance, which may allow identification of characteristics distinct to vCJD peripheral blood samples.
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Thüne, Katrin Verfasser], Inga [Akademischer Betreuer] [Zerr, Mikael [Gutachter] Simons, Silvio [Gutachter] Rizzoli, and Franc [Gutachter] Llorens. "Regional-dependent, comprehensive characterization of miRNA signatures in sporadic Creutzfeldt-Jakob Disease and early Alzheimer’s Disease-type neuropathology / Katrin Thüne ; Gutachter: Mikael Simons, Silvio Rizzoli, Franc Llorens ; Betreuer: Inga Zerr." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1196873984/34.
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Thüne, Katrin [Verfasser], Inga [Akademischer Betreuer] Zerr, Mikael [Gutachter] Simons, Silvio [Gutachter] Rizzoli, and Franc [Gutachter] Llorens. "Regional-dependent, comprehensive characterization of miRNA signatures in sporadic Creutzfeldt-Jakob Disease and early Alzheimer’s Disease-type neuropathology / Katrin Thüne ; Gutachter: Mikael Simons, Silvio Rizzoli, Franc Llorens ; Betreuer: Inga Zerr." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1196873984/34.
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Троцька, Ірина Олександрівна, Iryna Oleksandrivna Trotska та Ирина Александровна Троцкая. "Сучасні погляди на пріонові хвороби". Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/3720.
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Baiardi, Simone <1985>. "Effect of host genotype and prion strain on the phenotypic heterogeneity of Creutzfeldt-Jakob disease: the peripheral nervous system involvement and the spectrum of the genetic form." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/9097/1/baiardi_simone_tesi.pdf.
Full textAbstract:
The first study was designed to assess whether the involvement of the peripheral nervous system (PNS) belongs to the phenotypic spectrum of sporadic Creutzfeldt-Jakob disease (sCJD). To this aim, we reviewed medical records of 117 sCJDVV2, 65 sCJDMV2K, and 121 sCJDMM(V)1 subjects for symptoms/signs and neurophysiological data. We looked for the presence of PrPSc in postmortem PNS samples from 14 subjects by western blotting and real-time quaking-induced conversion (RT-QuIC) assay. Seventy-five (41.2%) VV2-MV2K patients, but only 11 (9.1%) MM(V)1, had symptoms/signs suggestive of PNS involvement and neuropathy was documented in half of the VV2-MV2K patients tested. RT-QuIC was positive in all PNS samples, whereas western blotting detected PrPSc in the sciatic nerve in only one VV2 and one MV2K. These results support the conclusion that peripheral neuropathy, likely related to PrPSc deposition, belongs to the phenotypic spectrum of sCJDMV2K and VV2, the two variants linked to the V2 strain.
The second study aimed to characterize the genetic/molecular determinants of phenotypic variability in genetic CJD (gCJD). To this purpose, we compared 157 cases of gCJD to 300 of sCJD. We analyzed: demographic aspects, neurological symptoms/signs, histopathologic features and biochemical characteristics of PrPSc. The results strongly indicated that the clinicopathological phenotypes of gCJD largely overlap with those of sCJD and that the genotype at codon 129 in cis with the mutation (i.e. haplotype) contributes more than the latter to the disease phenotype. Some mutations, however, cause phenotypic variations including haplotype-specific patterns of PrPSc deposition such as the “dense” synaptic pattern (E200K-129M), the intraneuronal dots (E200K-129V), and the linear stripes perpendicular to the surface in the molecular layer of cerebellum (OPRIs-129M). Overall, these results suggest that in gCJD PRNP mutations do not cause the emergence of novel prion strains, but rather confer increased susceptibility to the disease in conjunction with “minor” clinicopathological variations.
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Bishop, Matthew T. "Role of PRNP codon 129 genotype in defining strain transmission properties of human transmissible spongiform encephalopathy." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4236.
Full textAbstract:
The human prion protein (PrP) gene (PRNP) codon 129 (M/V) polymorphism is a susceptibility factor for variant Creutzfeldt-Jakob Disease (vCJD) and a major determinant of clinico-pathological phenotype in sporadic CJD. The role of codon 129 in defining susceptibility and strain transmission properties has been investigated in three lines of transgenic mice that express human PrP. The human PRNP gene has directly replaced the murine version, by gene targeting, and variation at codon 129 has given the three genotype lines (HuMM, HuMV, and HuVV). The genetics of these three mouse lines are otherwise identical, and therefore differences in transmission properties can be directly attributable to the codon 129 genotype. vCJD inoculation has shown that all three codon 129 genotype mice are susceptible with a ranking of transmission efficiency of HuMM>HuMV>HuVV. HuMM mice develop the most widespread neuropathology with features similar to human vCJD. Subclinical infection was noted in each mouse line. These data suggest that the vCJD strain is transmissible to humans of each of the three codon 129 genotypes, implying that non-MM cases of human infection with bovine spongiform encephalopathy (BSE) may exist but with long subclinical incubation periods. Inoculation of material from blood transfusion associated vCJD showed no change in transmission properties suggesting that the threat of a future epidemic of human-to-human vCJD infection has not been increased by adaptation of the vCJD strain. However the route of infection, for example via blood transfusion or surgery, may be more efficient that the original oral route of BSE infection. sCJD is classified into six subgroups according to clinico-pathological features, and defined by codon 129 genotype and electrophoretic mobility type (1 or 2) of disease associated PrPSc (MM1, MM2, MV1, MV2, VV1, VV2). Typical cases from each subgroup have shown specific transmission properties suggesting that the subgrouping is defining separate disease strains. The commonest subgroup (MM1) was the most transmissible and the HuVV mouse line the most susceptible host. These data outline the transmission risk from all sCJD types to recipients of each codon 129 genotype should an infection event occur, and show the significant role of recipient codon 129 genotype in defining the clinical or subclinical state and the success or failure of transmission. This is important for determining individual risk following known exposure, and for modelling the potential of iatrogenic infection from sCJD patients.
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Gawinecka, Joanna Verfasser], Mathias [Akademischer Betreuer] [Bähr, Inga [Akademischer Betreuer] Zerr, Thomas [Akademischer Betreuer] Bayer, and Mikael [Akademischer Betreuer] Simons. "Prion protein-induced proteome alterations in sporadic Creutzfeldt-Jakob disease and in SH-SY5Y cell culture model / Joanna Gawinecka. Gutachter: Inga Zerr ; Thomas Bayer ; Mikael Simons. Betreuer: Mathias Bähr." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1042639671/34.
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DEL, GALLO FEDERICO. "SONNO E MALATTIE NEURODEGENERATIVE IN MODELLI ANIMALI." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/232729.
Full textAbstract:
I disturbi del sonno rappresentano una manifestazione clinica tipica di gran parte delle malattie neurodegenerative. Insonnia, ipersonnia, parasonnie, perdita di specifiche fasi del sonno e disorganizzazione del ciclo veglia-sonno sono alcune delle manifestazioni che caratterizzano le sinucleinopatie, le prionopatie e le taupatie. Recenti evidenze hanno rilevato che in molti casi i disturbi del sonno possono precedere l’insorgenza del quadro sintomatico tipico di queste patologie. In particolare, è stato osservato che la presenza di RBD (disturbo del comportamento durante il sonno REM) nella sua forma idiopatica (iRBD) sembra costituire un fattore predittivo per l’insorgenza di una futura sinucleinopatia. L’utilizzo di modelli animali è uno degli strumenti più utilizzati in campo biomedico per lo studio della patologia umana e lo sviluppo di nuovi metodi più efficaci per la diagnosi e il trattamento di malattie sia umane che animali.
Scopo di questa tesi è stato quello di verificare se le alterazioni del sonno fossero presenti anche in modelli murini di alcune malattie neurodegenerative con diversa eziologia. Tra queste abbiamo preso in considerazione l’Insonnia Fatale Familiare (FFI), la malattia di Creutzfeldt-Jakob (CJD) e la malattia di Alzheimer (AD). In seconda istanza, la disponibilità di un modello murino a diversi stadi evolutivi, ha permesso di indagare l’ipotesi di una precoce insorgenza dei disturbi del sonno nella malattia di Creutzfeldt-Jakob. A questo scopo è stato registrato poligraficamente e analizzato il ciclo veglia-sonno in modelli murini delle tre patologie sopra citate.
Nel primo esperimento è stato analizzato il ciclo veglia-sonno di topi transgenici che esprimevano l’omologo murino della mutazione (D178N/M129) al gene Prnp che codifica per la proteina prionica (PrP). Questa mutazione nell’uomo è associata a insonnia fatale familiare. Il ciclo veglia-sonno di questi animali è stato confrontato con due ceppi di topi di controllo: i) topi wild type (C57BL/6J) e ii) topi knock-out per la PrP.
Nel secondo esperimento sono state analizzate le caratteristiche del sonno in topi transgenici recanti l’omologo murino della mutazione (D178N/V129) al gene Prnp, che nell’uomo porta a una forma familiare di Creutzfeldt-Jakob (CJD178). Il ciclo veglia-sonno di questi topi è stato confrontato con i ceppi di controllo già descritti per il primo esperimento. Ciascun ceppo di topi, inoltre, è stato analizzato a tre diverse età: 6, 12 e 18 mesi che rappresentano stadi evolutivi diversi (rispettivamente: giovani, adulti e anziani); questo al fine di valutare l’evoluzione delle alterazioni del sonno e la loro effettiva insorgenza.
Nel terzo esperimento è stato preso in considerazione un modello, in acuto, di malattia di Alzheimer (AD). Il ciclo veglia-sonno di topi C57BL/6J è stato analizzato in seguito a somministrazione intracerebroventricolare (ICV), in acuto, di oligomeri sintetici di β-amiloide (A-β1-42). Questi sono i costituenti delle placche amiloidi riscontrate in pazienti affetti da AD. La somministrazione veniva eseguita all’inizio della fase di luce del ciclo luce-buio. In seguito, il ciclo veglia-sonno era registrato poligraficamente per le successive 24 ore in condizioni normali di laboratorio. Questa condizione è stata confrontata con il ciclo veglia-sonno degli stessi topi (disegno within) in seguito a somministrazione di due trattamenti di controllo: i) un veicolo (tampone fosfato salino, PBS) e ii) i monomeri sintetici di β-amiloide.
In tutti e tre i modelli murini considerati si sono osservate marcate alterazioni del ciclo veglia-sonno, nei termini di una riduzione del sonno REM. La perdita di questa fase era essenzialmente dovuta a una diminuzione del numero dei suoi episodi. I modelli murini delle tre malattie neurodegenerative mostravano, infatti, una certa difficoltà nell’iniziare un episodio di sonno REM. La decurtazione di sonno REM era accompagnata, anche, da una riduzione del potere spettrale della banda theta durante gli episodi di sonno REM. L’analisi dei tracciati elettroencefalografici (EEG) ha, inoltre, messo in evidenza la presenza di attività EEG anomala, consistente in complessi polifasici di ampio voltaggio e con un picco di frequenza attorno ai 7 Hz. Le registrazioni del modello murino di CJD a diversi stadi evolutivi hanno evidenziato che le alterazioni del sonno in questo modello si presentano già a 12 mesi di età, ancora prima dell’insorgenza dei sintomi tipici della patologia.
Le alterazioni del sonno sono, quindi, presenti anche in modelli murini di alcune malattie neurodegenerative, incluse quelle in cui il disturbo del sonno non rappresenta il sintomo principale. Nel modello murino di CJD, inoltre, l’alterazione del normale ciclo veglia-sonno sembra precedere la manifestazione del quadro sintomatico tipico della patologia.
Questi dati suggeriscono una stretta relazione tra alterazioni del ciclo veglia-sonno e malattie neurodegenerative. Per questo motivo, in campo clinico e diagnostico, sarebbe opportuno porre una maggiore attenzione ai disturbi del sonno. Questi sembrano essere, infatti, parte integrante di molte malattie contraddistinte da degenerazione neuronale. L’alterazione del normale ciclo veglia-sonno potrebbe avere, inoltre, un valore predittivo per alcune delle patologie neurodegenerative o comunque essere un valido aiuto nel processo diagnostico.
In futuro, il miglioramento della qualità del sonno e/o la normalizzazione del ciclo veglia-sonno potrebbero essere validi strumenti al fine di prevenire la neurodegenerazione e l’insorgenza di alcune malattie neurodegenerative, o almeno rappresentare un approccio palliativo in corso di malattia.<br>Sleep disturbances represent an important clinical feature in different neurodegenerative disorders. Insomnia, hypersomnia, parasomnia, loss of specific sleep stages and alterations in circadian rhythms characterize synucleinopathies, prionpathies and tauopathies. Recent evidences highlight that, in many instances, sleep alterations could disclose the onset of a neurodegenerative disorder. In particular, it has been shown that the idiopathic form of the REM sleep Behavior Disorder (iRBD) could be a prognostic factor for the development of a future synucleinopathy. The use of animal models is very common in biomedical research and is essential to develop new and more effective methods for diagnosis and treating disease that affecting both humans and animals.
The first aim of this thesis is to verify if murine models of neurodegenerative disorders with different aetiology show sleep alterations similar to those observed in humans. Secondly, the availability of a murine model at different stages of the disease’s course allowed us to investigate whether the sleep alterations precede (or not) the development of other features of the disease. To this purpose, the sleep-wake cycle was poligraphically recorded and analyzed in the murine models of three neurodegenerative disorders: i) Fatal Familial Insomnia (FFI), ii) Creutzfeldt-Jakob disease (CJD) and iii) Alzheimer’s disease (AD).
In the first experiment we analyzed the sleep-wake cycle of transgenic mice expressing the murine homolog of the D178N/M129 human mutation at the Prnp gene, encoding for prion protein (PrP). This kind of mutation is associated in human with FFI. We compared the sleep-wake cycle of these animals with two control mice strains: i) wild-type mice (C57BL/6J, WT mice) and ii) PrP knock-out mice (KO mice).
In the second experiment we analyzed the sleep-wake cycle in mice expressing the murine homolog of the D178N/V129 human mutation, associated with a familial form of Creutzfeldt-Jakob disease (CJD178). We compared the sleep of these mice with WT and KO mice. In order to evaluate the course of sleep alterations and their onset, each mice strain was recorded at three different ages: 6, 12 and 18 months of age. At these ages animals can be considered as young, adult and old, respectively.
In the third experiment, we considered an acute mice model of Alzheimer’s disease (AD). C57BL/6J mice were intracerebroventricularly injected with three different solutions: i) synthetic oligomers of amyloid-β (A-β1-42); ii) phosphate buffer saline, PBS (vehicle); iii) synthetic monomers of amyloid-β (A-β1-42). A-β1-42 oligomers are the main elements of A-β plaques, observed in AD patients. The other two solutions were administered as control condition. All mice received all the three injections (within design) at the light onset. Hereafter, the sleep-wake cycle was polygraphically recorded during the next 24 hours in baseline conditions. We compared the sleep-wake cycle of mice following the injection of A-β1-42 oligomers with that followed the administration of the control conditions.
In all three experiments the murine models showed marked sleep-wake alterations, in particular a reduction of the amount of REM sleep. The loss of REM sleep was due to a reduction of the number of REM sleep bouts. In other words, the murine models showed a difficulty in entering REM sleep. The reduction of the time spent in REM sleep was combined with a decrease of EEG theta power during REM sleep bouts. Moreover, the EEG activity of murine models was characterized by bursts of polyphasic complexes, peaking at around 7 Hz. At last, analyses of the murine model of CJD at different ages revealed that sleep alterations were already present at 12 months of age, before any other evidence of clinical signs.
As well as in humans, sleep alterations are have been described in animal models of neurodegenerative disorders, including those in which sleep disturbance is not considered a main feature. Moreover, in the murine model of CJD, the alteration of the normal sleep-wake cycle seems to precede the onset of other clinical signs of the disease.
These data suggest the existence of a relationship between sleep-wake cycle alterations and some neurodegenerative disorders and suggest to pay more attention to sleep disturbances, in clinic and diagnostic field. Sleep alterations seem to represent an important feature of numerous neurodegenerative disorders and could be considered a prognostic factor for the evolution of these disorders and something to be taken into account in the evaluation of the clinical picture.
In the future, it would be useful considering the enhancement of sleep quality and/or the normalization of sleep-wake cycle as a new tool to prevent the evolution of neurodegeneration and the onset of several neurodegenerative disorder, or at least represent a palliative care in course of the disorders.
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Tahir, Waqas Verfasser], Saima [Akademischer Betreuer] Zafar, Mikael [Gutachter] Simons, Michael [Gutachter] Hoppert, and Inga [Gutachter] [Zerr. "Identification and characterization of proteomic regulations in the cerebellum region of brain in MM1 and VV2 subtypes of sporadic Creutzfeldt-Jakob disease (sCJD) : Proteome Profiling of sCJD brain tissue / Waqas Tahir ; Gutachter: Mikael Simons, Michael Hoppert, Inga Zerr ; Betreuer: Saima Zafar." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1132336813/34.
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Soldevila, Trepat Marta. "Genetic variation in humans and chimpanzees in the prion protein gene." Doctoral thesis, Universitat Pompeu Fabra, 2005. http://hdl.handle.net/10803/7189.
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En el gen de la proteïna priònica, o PRNP, hem observat que el particular patró de variació que hem trobat basant-nos en dades de seqüenciació en humans es deu a selecció positiva, i que el mètode utilitzat per detectar selecció és crític. Utilitzant dades basades en SNPs es pot introduir un biaix al aplicar tests de neutralitat basats en diversitat de seqüències, i això pot portar a conclusions errònies. A més, hem vist que els polimorfismes en els codons 129 i 219 presenten gran diferències de freqüència en diferents poblacions humanes i també hem vist que aquestes posicions estan fixades en ximpanzés. La variació trobada en controls ha estat comparada amb el patró de variació existent en pacients per la mateixa regió. La reseqüenciació del gen PRNP en un gran nombre de mostres humanes i de ximpanzés ens ha permès obtenir un gran nombre d´informació d´aquest gen.<br>In the prion gene or PRNP, we have observed that the particular pattern of variation that we have found in this gene based on sequencing data in humans is due to positive selection, and that the method and the approach used to detect this selection critical. Ascertainment bias can be introduced by using SNP data and applying neutrality tests based on sequence diversity, therefore leading to anomalous conclusions being drawn. Moreover, we have seen that polymorphisms in codon 129 and 219 have big differences in frequency in different human populations and we have also seen that these positions are fixed in chimpanzees. The normal variation that we found in controls have been then compared with patients for the same region. The resequencing of PRNP in a very large sample of humans and chimpanzees has provided a great deal of information on this gene.
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Kittner, Cornelia. "Risikofaktoren der sporadischen Creutzfeldt-Jakob-Krankheit." Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-AF4A-9.
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Fincke, Fabian. "Doxycyclin bei der sporadischen Creutzfeldt-Jakob-Krankheit." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B1C9-B.
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Mohanty, Siddhant. "Exploring potential drugs against Scrapie disease and Creutzfeldt-Jakob disease using molecular docking techniques." Thesis, 2014. http://ethesis.nitrkl.ac.in/6366/1/110BT0606-13.pdf.
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Scrapie is a lethal, degenerative sickness that influences the sensory systems of sheep and goats. Creutzfeldt-Jakob infection is a degenerative neurological issue that is serious and constantly lethal in human. Both the maladies are brought about by a protein called prion. The transformation of the á-helical, cell isoform of the prion protein (Prpc) to the insoluble, â-sheet rich irresistible, infection creating isoform (PrPsc) is the key occasion in prion illness. I have discovered two prion proteins on which the inhibitors could be docked. They are 1XYU (sheep) and 1FO7(human). I have additionally searched for different inhibitors which might be utilized to tie with the dynamic locales of the two proteins. Some of them are tannin, quinacrine, astemizole, terfenadine, lovastatin, amantadine, acyclovir, clonazepam, pentosan polysulfate, perk inhibitors, rivastigmine,etc.
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Osmanlioglu, Seyma. "Steroid-responsive Enzephalopathie bei Autoimmunthyreoiditis als Differentialdiagnose der Creutzfeldt-Jakob-Krankheit." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-86F1-D.
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Gawinecka, Joanna. "Prion protein-induced proteome alterations in sporadic Creutzfeldt-Jakob disease and in SH-SY5Y cell culture model." Thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-ADDF-9.
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Thüne, Katrin. "Regional-dependent, comprehensive characterization of miRNA signatures in sporadic Creutzfeldt-Jakob Disease and early Alzheimer’s Disease-type neuropathology." Doctoral thesis, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0005-126B-F.
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Kaune, Judith (Jansen). "Erstsymptom, Erstdiagnose und ärztlicher Erstkontakt bei Patienten mit sporadischer Creutzfeldt-Jakob-Krankheit in Deutschland." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5E1C-4.
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Hintergrund: Die sporadische Creutzfeldt-Jakob-Krankheit (sCJK) ist eine seltene neurodegenerative Erkrankung. Bisher existieren nur wenige Studien im Hinblick auf das Initialstadium der Erkrankung. Ziel dieser Studie war es unter Berücksichtigung des M129V-Genotyps und des Prionproteintyps maximal zwei Erstsymptome begrenzt auf einen Zeitraum von 2 Wochen, den ärztlichen Erstkontakt und die erste fachärztliche Diagnose zu erfassen.
Material und Methoden: In der vorliegenden Dissertation wurden retrospektiv Akten von 492 Patienten mit einer neuropathologisch gesicherten oder klinisch wahrscheinlichen sCJK ausgewertet, die im Zeitraum von 1993 bis 2003 an das Göttinger Surveillance-Zentrum für CJK gemeldet worden waren. Bei 204 Patienten des Gesamtkollektivs war zusätzlich der Prionproteintyp bekannt. Mithilfe eines Dokumentationsbogens wurden die relevanten Parameter erfasst und statistisch ausgewertet.
Ergebnisse: Zehn Prozent aller Patienten klagten über Prodromalsymptome wie Kopfschmerz, Müdigkeit, gestörte Schlaf-Wach-Rhythmik, Summen bzw. "komisches Gefühl im Kopf", Hörstörungen, Gewichtsverlust oder Photophobie. Patienten mit dem Subtyp MV-2 oder VV-1 gaben keine Prodromalsymptome an. Das häufigste Erstsymptom stellte die Demenz (37%) dar, gefolgt von zerebellären (34%), visuellen (15%) oder psychiatrischen (14%) Symptomen. Fünfzehn Prozent berichteten innerhalb von 2 Wochen bereits über 2 Erstsymptome. Als erster ärztlicher Kontakt wurde der Hausarzt (41%) aufgesucht, gefolgt vom niedergelassenen Neurologen (17%) oder einem Krankenhaus (13%), unabhängig von der Spezialisierung der Abteilung. Die fachärztliche Erstdiagnose lautete nur in 35% der Fälle CJK (in 42% bei MM-Patienten, 28% bei MV-Patienten, 25% bei VV-Patienten). Die Meldung eines CJK-Verdachtsfalles an das Göttinger CJK-Surveillance-Zentrum erfolgte überwiegend durch Neurologen, gefolgt von Psychiatern oder von anderen Berufsgruppen.
Diskussion: Diese erste detaillierte Analyse von Erstsymptomen und ärztlichen Erstkontakten unterstreicht, wie relevant das Wissen von CJK und den atypischen CJK-Subtypen für Ärzte verschiedener Fachrichtungen ist. Hieraus entsteht die Hoffnung, dass in Zukunft insbesondere auch atypische CJK-Formen frühzeitig erkannt werden können.
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Wohlhage, Marie Charlotte. "Entwicklung eines PrPc-Detektions-Assays zur Analyse der Fragestellung, welchen Einfluss PRNP-Mutationen oder Genpolymorphismen in CJK-Patienten auf die PrPc-Expression haben." Doctoral thesis, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0003-C1BA-1.
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Tahir, Waqas. "Identification and characterization of proteomic regulations in the cerebellum region of brain in MM1 and VV2 subtypes of sporadic Creutzfeldt-Jakob disease (sCJD)." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0023-3E48-F.
Full textAbstract:
La maladie sporadique de Creutzfeldt-Jakob (sCJD) est une encéphalopathie spongiforme transmissible mortelle caractérisée par une large gamme de manifestations cliniques et pathologiques. Les caractéristiques pathologiques de la SDMC dépendent en grande partie de la présence d'une forme mal repliée de protéine prion cellulaire (PrPC); Connu sous le nom de PrPSC et polymorphisme (méthionine et valine) au codon 129 du gène PRNP qui code pour PrPC. Les facteurs étiologiques exacts de la MCSJ sont encore inconnus. Le génotype Codon 129 du gène PRNP et le type de PrPSC (type 1 ou type 2) influent sur l'hétérogénéité de la maladie telle que définie par des caractéristiques pathologiques spécifiques de la région qui peuvent réguler les voies moléculaires qui conduisent au développement de phénotypes pathogènes dépendants des sous-types. Dans cette étude, nous avons étudié l'ensemble de la réglementation protéomique dans la région cerebrale du cerveau des deux sous-types les plus répandus (MM1 et VV2) des patients atteints de SDMC utilisant une électrophorèse sur gel bidimensionnelle (2DE) et une spectrométrie de masse. L'analyse de toutes les taches de protéines sur les gels 2DE avec le logiciel DECODON Delta2D a révélé vingt-cinq taches de protéines différenciées et l'identification de ces taches avec MALDI-TOF MS / MS a révélé quatre-vingts trois protéines différentiellement réglementées dans les deux sous-types dans la région du cervebelle du cerveau par les patients atteints de sCJD. Quarante protéines dans le sous-type MM1 et quarante-trois protéines dans le sous-type VV2 ont été classées. Douze protéines étaient communément réglementées dans les deux sous-types, dont cinq d'entre elles présentaient une régulation expresnelle inverse et le repos sept avait une régulation expresnelle similaire dans les deux sous-types. Les trois principaux mécanismes moléculaires cellulaires réglementés dans les deux sous-types comprennent: i) le cycle cellulaire; L'expression des gènes et la mort cellulaire, ii) - la réponse au stress cellulaire / le stress oxydatif et iii) - la transduction du signal et les fonctions synaptiques La plupart des protéines sous la classification des réponses au stress cellulaire étaient associées aux fonctions moléculaires cellulaires liées au stress oxydatif. DJ-1 qui est un capteur bien connu de stress oxydatif, a également été jugé réglementé dans la catégorie des réponses au stress cellulaire. Le DJ-1 protège les cellules contre le stress oxydatif directement en translocant au noyau pour l'activation de gènes antioxydants et indirectement en activant la voie Nrf2 / ARE. Nos résultats expérimentaux ont démontré l'activation de la voie Nrf2 / ARE dans les sous-types MM1 et VV2 de sCJD. Le DJ-1 a également montré une régulation positive significative dans son expression de l'ARNm dans les sous-types MM1 et VV2 mais l'expression des protéines uniquement dans le sous-type VV2 dans le cervelet du cerveau des patients atteints de sCJD. En outre, l'expression de la protéine DJ-1 a également été augmentée au cours des stades pré-symptomatiques et symptomatiques dans le cervelet du cerveau des modèles de souris de sCJD (MM1 et VV2) et pendant le stade clinique dans les échantillons de CSF des patients atteints de SDMC. Ces résultats suggèrent l'implication du stress oxydatif lors de la pathophysiologie de la SDMC et l'utilisation de DJ-1 comme capteur potentiel de stress oxydatif pendant la phase clinique de la sCJD.
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Krautwald, Lisa. "Klinische und diagnostische Eigenschaften der sporadischen Creutzfeldt-Jakob-Krankheit bei Patienten mit positiver Familienanamnese für Demenz oder Morbus Parkinson." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-8780-1.
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ZIEL Als Ursache für die sporadische Creutzfeldt-Jakob Krankheit wird eine spontane Konfigurationsänderung des Prionproteins diskutiert. Die Annahme der Beeinflussung fehlgefaltete Proteinketten, welche bei neurodegenerativen Erkrankungen wie der Alzheimer Demenz oder Parkinson vorliegen, auf die Entwicklung einer zweiten Proteinfehlfaltung stellen eine mögliche Verbindung zwischen dem Auftreten neurodegenerativer Erkrankungen und Prionerkrankungen her. Das Ziel dieser retrospektiven Untersuchung ist es, die klinischen und diagnostischen Eigenschaften von sCJD-Patienten mit Morbus Parkinson oder Demenz in der Familienanamnese zu analysieren um die Diagnostik verbessern zu können. METHODEN Für die vorliegende Arbeit wurde ein Kollektiv aus 133 Patienten mit sicherer oder wahrscheinliche sCJD mit bekannter Ausprägung am Codon-129 rekrutiert. Bei den Geschwistern, den Eltern oder den Großeltern mütterlicher- oder väterlicherseits lag ein Parkinsonsyndrom oder eine dementielle Erkrankung vor. Gegenüber gestellt wurde diesem eine Kontrollgruppe nach Zuordnung nach Geschlecht, Alter (+/- 5 Jahre) sowie PRnP-Codon 129-Genotyp. Der Schwerpunkt der Arbeit liegt auf der klinischen Symptomatik, den Liquorparametern und den Ergebnissen aus bildgebenden Verfahren wie Elektroenzephalographie, zerebraler Computertomographie und Magnetresonanztomographie. ERGEBNISSE Erstes neurologisches Symptom waren zerebelläre Störungen (Ataxie), psychiatrische und visuelle Störungen, während eine dementielle Entwicklung erst im Verlauf hinzutrat. Beim Fortschreiten der Erkrankung wurden Pyramidenbahnzeichen häufiger und extrapyramidale Störungen deutlich seltener diagnostiziert. Insgesamt fiel vom klinischen Erscheinungsbild häufiger die Gruppe FA-Parkinson auf (beispielsweise häufiges Vorkommen von Antriebsstörungen), während FA-Demenz meist der Kontrollgruppe glich. Mit dem Nachweis von PSWC im EEG in 53 % bei FA-Demenz und 61 % bei FA-Parkinson übertrifft die Sensitivität der EEG-Untersuchung nicht die für die sCJD geltende von 64 % (Steinhoff et al. 2004). Mit einem Nachweis der Proteine 14-3-3 im Liquor in 96 % (FA-Demenz) und 100 % (FA-Parkinson) ergibt sich eine ebenso hohe Sensitivität wie für die sCJD bereits postuliert (94 %, Zerr et al. 2000a). Auch die Sensitivität der NSE ist bei den Patienten dieser Arbeit sehr hoch, während der Liquormarker S100b-Protein bei FA-Parkinson-Patienten deutlich seltener den cut-off-Wert erreicht. Ein CJD-typischer MRT-Befund (hyperintense Basalganglien oder kortikale Signalsteigerung) wurde nur in 52 % bei FA-Demenz und bei 49 % bei FA-Parkinson festgestellt. SCHLUSSFOLGERUNG Schließlich lässt sich festhalten, dass bei diesen Patienten nicht vorwiegend eine Demenz wegweisend zur Diagnose ist, sondern auf das Vorliegen zerebellärer oder psychiatrischer Symptome geachtet werden muss. In der Diagnostik kommt dem EEG mit einer hohen Sensitivität eine große Bedeutung zu, während die MRTUntersuchung weniger wegweisend ist. Bei Morbus Parkinson in der Familie unterstützt die Liquoruntersuchung die Diagnostik nicht so stark, während gerade pathologische Werte des Tau-Proteins und des Amyloid-ß 1-42 bei Patienten mit Demenz in der Familie auf eine sCJD hindeuten.
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Montag, Judith. "Übertragung von BSE auf nicht humane Primaten als Modell für die variante Creutzfeldt-Jakob Erkrankung (vCJD) im Menschen." Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-0006-AC5B-8.
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BONGIANNI, Matilde. "Detection of pathological prion protein by RT-QuIC analysis of cerebrospinal fluid and olfactory neuroepithelium of patients with sporadic Creutzfeldt-Jakob disease." Doctoral thesis, 2013. http://hdl.handle.net/11562/540350.
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ITALIAN SUMMARY
PREMESSA: La diagnosi definitiva della forma sporadica di Creutzfeldt-Jakob (sCJD) in pazienti ancora in vita rimane una sfida. La Real time quaking-induced conversion (RT-QuIC) testata nel fluido cerebro- spinale (CSF) ha permesso l’identificazione di pazienti sCJD con una sensibilità del 80-90%. Poichè la CJD è una malattia trasmissibile, non trattabile e fatale, è importante effettuare una diagnosi corretta.
Uno studio precedente ha individuato la presenza della proteina prionica patologica (PrP) nell’ epitelio olfattivo di pazienti sCJD. Questo studio ci ha spinto ha verificare se l’impiego dell’RT-QuIC utilizzando campioni di brushings nasale può migliorarne la diagnosi pre-mortem nei casi di sCJD.
METODI: Abbiamo testato i brushings di neuroepitelio olfattivo da pazienti con diagnosi di sospetta sCJD e non-CJD utilizzando l’RT-QuIC.
L’RT-QuIC è una tecnica di amplificazione in vitro che utilizza una proteina prionica ricombinante (rPrPc) come substrato per la PrP patologica. Il substrato viene convertito in fibrille amiloidee che possono essere monitorate in tempo reale utilizzando il marcatore fluorescente thioflavina T (ThT).
RISULTATI: Abbiamo osservato una forte positività all’RT-QuIC in 7 campioni su 7 di brushings nasale di pazienti con probabile sCJD, e non negli 11 controlli negativi. Questo risultato ha determinato una sensibilità e una specificità del 100%.
In confronto abbiamo osservato che 6 campioni su 7 di CSF appartenenti allo stesso gruppo di pazienti sCJD erano positivi all’RT-QuIC, determinando quindi una sensibilità dell’86%. Inoltre la quantificazione con RT-QuIC dei campioni di brushing nasali ha mostrato che contengono un’ attività di seeding di ~105-107.
CONCLUSIONI: L’ utilizzo dei campioni di brushings nasale insieme al test RT-QuIC potrebbero facilitare e rafforzare la diagnosi pre-mortem di sCJD.
Inoltre, gli alti livelli di attività di seeding della proteina prionica trovati in questi campioni suggeriscono un alto grado di trasmissibilità del prione attraverso la mucosa olfattiva.<br>ABSTRACT
BACKGROUND: Definitive diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) in living patients remains a challenge. Real time quaking-induced conversion (RT-QuIC) testing of cerebrospinal fluid (CSF) has allowed identification of sCJD patients with 80-90% sensitivity. However, because CJD is transmissible, untreatable and fatal, it is important to eliminate missed diagnoses. Previous work identified abnormal prion protein (PrP) in olfactory neuroepithelium of sCJD patients, prompting us to investigate whether RT-QuIC analysis of easily accessible nasal brushings might improve sCJD diagnosis.
METHODS: We tested olfactory neuroepithelium brushings from sCJD and non-CJD patients using RT-QuIC, which is an ultrasensitive, multi-well plate-based fluorescence assay involving prion-seeded polymerization of recombinant PrP into amyloid fibrils.
RESULTS: We observed strong positive RT-QuIC reactions seeded with nasal brushings from 7 of 7 probable sCJD patients, but none of 11 negative controls, providing 100% sensitivity and 100% specificity. By comparison, 6 out of 7 CSF samples from the same group of sCJD patients was RT-QuIC-positive, giving 86% sensitivity. Quantitative RT-QuIC showed that olfactory brushings contained ~105-107 prion seeds.
CONCLUSIONS: Nasal brushing-based RT-QuIC may markedly facilitate and strengthen diagnosis of sCJD. Moreover, the high levels of prion seeding activity found in these samples raises concerns about transmissible sCJD prion shedding from olfactory mucosa.