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S Poser

Publications and source records attributed to S Poser.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Diffusion-weighted MRI in patients with Creutzfeldt-Jakob disease].

Today the diagnosis of Creutzfeldt-Jakob disease (CJD) is proven only postmortem or by evidence of neuropathology. During the patient's lifetime EEG recordings or cerebrospinal fluid analysis may support the diagnosis. In most cases, T2-MRI scans show hyperintensities of the basal ganglia. A new imaging technique called diffusion-weighted MRI (DWI) has recently been established. The sensitivity of DWI was evaluated in five patients suspected of CJD. All five cases showed hyperintense signal changes in the basal ganglia on DWI sequences. These findings were more pronounced in DWI than in T2, FLAIR, or PD-weighted images. Thus, DWI seems to be the most sensitive sequence for detecting changes in patients with suspected CJD. Moreover, its short scanning time ensures that fewer artifacts occur, especially in the case of myoclonus.

Aged↗
PubMed2000

European surveillance on Creutzfeldt-Jakob disease: a case-control study for medical risk factors.

Medical risk factors for Creutzfeldt-Jakob disease (CJD) were analyzed in a prospective ongoing case-control study based on European CJD surveillance. Detailed data on past and recent medical history were analyzed in 405 cases and controls matched by sex, age, and hospital. Data were correlated with polymorphism at codon 129 of the prion protein gene. Our analysis did not support a number of previously reported associations and failed to identify any common medical risk factor for CJD. Although not statistically significant, brain surgery was associated with an increased risk of CJD. A detailed medical history should be obtained in every suspected CJD case in order to identify iatrogenic sources of CJD.

Adult↗
PubMed2000

Creutzfeldt-Jakob disease and oxidative stress.

OBJECTIVES: Substantial evidence supports the hypothesis that oxygen free radicals are involved in various neurodegenerative disorders. To assess the presence of oxidative stress in Creutzfeldt-Jakob disease (CJD) we examined the concentrations of malondialdehyde (MDA) as an established marker of lipid peroxidation. MATERIAL AND METHODS: MDA was quantified by high performance liquid chromatography (HPLC) in cerebrospinal fluid (CSF; n=12) and in serum (n=11) samples of CJD patients and healthy controls (n = 15). RESULTS: Mean values in healthy controls: 2.56 nmol/ml +/- 0.46 (CSF) and 1.94 nmol/ ml +/- 0.67 (serum); mean values in CJD patients: 2.64 nmol/ml +/- 0.67 (CSF) and 1.68 nmol/ml +/- 0.79 (serum). No significant (P>0.05) difference between CJD patients and controls was observed. CONCLUSIONS: The results indicated that the CSF and serum of CJD patients showed no higher endogenous levels of MDA as compared to normal healthy controls. These findings provide no evidence for an additional role of oxidative stress in the pathogenetic mechanism underlying CJD neurodegeneration.

Biomarkers↗
PubMed2000

[Perspectives on medical research by relatives of patients with Creutzfeldt-Jakob disease].

OBJECTIVE: To assess the attitude of Creutzfeldt-Jakob patients relatives and of relatives of cognitively unimpaired individuals towards dementia research by a questionnaire survey. METHODS: 42 relatives of cases and 41 controls who were interviewed within the german part of the European Union collaborative study of CJD were asked to answer structured questions concerning their personal attitude towards three hypothetical projects: a diagnostic research project without personal benefit, a project with possible therapeutic option and a study of hereditary dementia. RESULTS: 31 relatives of cases and 26 relatives of the controls were willing to participate in this survey. In both groups the willingness to participate in dementia research is high. Research without approval of patients or relatives is rejected in most cases. Relatives want to decide to which extent genetic results are used for scientific or personal purposes. CONCLUSIONS: Although research with (and for) demented patients is restricted by the law in many countries to certain limits, relatives are willing to participate in these efforts to a greater extend than expected. As long as the responsible physicians will respect their demented patients as severely ill human beings, the view towards research is this field might be as positive as shown in this sample.

Adult↗
PubMed2000

Current clinical diagnosis in Creutzfeldt-Jakob disease: identification of uncommon variants.

According to the recently established molecular basis for phenotypic heterogeneity of sporadic Creutzfeldt-Jakob disease (CJD), six different phenotypes are characterized by the size of the protease-resistant fragment of the pathological prion protein (types 1 and 2) and homozygosity or heterozygosity for methionine or valine at codon 129 of the prion protein gene (designated by MM1, MM2, MV1, MV2, W1, and W2). In the present investigation, we analyzed the value of commonly used clinical tests (electroencephalogram [EEG], detection of 14-3-3 protein in cerebrospinal fluid [CSF], and hyperintensity of the basal ganglia in magnetic resonance imaging) for the clinical diagnosis in each CJD phenotype. The detection of periodic sharp and slow wave complexes in the EEG is reliable in the clinical diagnosis of MM1 and MV1 patients only. The CSF analysis for 14-3-3 protein showed high sensitivity in all analyzed subgroups with the exception of MV2 patients. Valine-homozygous patients had a negative EEG, but most had detectable levels of neuronal proteins in the CSF. The sensitivity of the magnetic resonance imaging was 70%, irrespective of the subgroup, but was particularly reliable in the clinical diagnosis of MV2 patients. The widening spectrum of diagnostic techniques in CJD is not only useful in the increased accuracy of the clinical diagnosis but should also lead to the identification of more atypical cases of sporadic CJD.

14-3-3 Proteins↗
PubMed1999

Effect of interferon beta on human myelin basic protein-specific T-cell lines: comparison of IFNbeta-1a and IFNbeta-1b.

The effect of interferon (IFN)beta-1a and IFNbeta-1b on human myelin basic protein-reactive T-cell lines was investigated. Both drugs inhibited proliferation and production of lymphotoxin (LT), whereas the production of interleukin-4 was not altered and interleukin-10 was induced. Comparing equal numbers of units IFNbeta-1a and -1b showed almost identical results. These in vitro data indicate that the immunomodulatory capacity of both interferons with respect to T cells paralleled their antiviral effect.

Analysis of Variance↗
PubMed1999

Increase of neuron-specific enolase in patients with Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative human disorder with an incidence of one case per 1000000 per year. Recently new diagnostic tests such as neuron-specific enolase (NSE), S-100, tau-protein and protein 14-3-3 have been established as markers in prion diseases. NSE is elevated in case of rapid nerve cell loss so quantitative measurement of NSE in cerebrospinal fluid (CSF) might correlate with the disease progression. To further evaluate this hypothesis we analysed longitudinal CSF samples from 16 CJD patients. The first spinal tap was taken two weeks after the first clinical signs of a neurodegenerative disorder. This showed an elevation of NSE which continued during the course of the disease. Longitudinal examination of neuron-specific enolase in cerebrospinal fluid therefore may be useful for differentiation between CJD and other dementias.

14-3-3 Proteins↗
PubMed1999

The Heidenhain variant of Creutzfeldt-Jakob disease.

OBJECTIVE: To investigate whether typical neuropathological and radiological findings can be identified in patients with the clinical diagnosis of the Heidenhain variant of Creutzfeldt-Jakob disease (CJD). DESIGN: Case study. The clinical symptoms, neuropathological findings, electroencephalograms, magnetic resonance images, and cerebrospinal fluid samples of 14 Heidenhain cases were evaluated. Neuropathological changes were compared with those in a group of 14 patients with ataxia as the leading clinical sign. SETTING: A university hospital, base of the German National Creutzfeldt-Jakob Disease Surveillance Study. PATIENTS: Medical records of 169 neurologically examined patients with prospectively classified and neuropathologically confirmed CJD were analyzed. MAIN OUTCOME MEASURE: Difference in neuropathological and radiological findings between patients with the Heidenhain variant and other patients with CJD. RESULTS: Of 169 patients with confirmed CJD, 20% showed characteristic clinical findings such as blurred vision, visual field restriction, metamorphopsia, or cortical blindness. Disease course of the Heidenhain group, as compared with the group of all patients with definite CJD, was significantly shorter (5.7 months vs 7.5 months; P=.02, t test). Neuropathological examination of patients with the Heidenhain variant showed most pronounced changes in the occipital lobe but less damage in the cingulate gyrus and basal ganglia compared with 14 patients with CJD who had ataxia as the leading clinical sign. Eleven (92%) of 12 genetically analyzed Heidenhain cases were homozygous for methionine at codon 129 of the prion protein gene (PRNP). In 9 of 9 cases, the 14-3-3 protein was present. In 7 (78%) of 9 cases, the level of neuron-specific enolase was elevated, with a concentration above 35 ng/mL. Periodic sharp-wave complexes were observed in 11 (78%) of the 14 cases. In 7 (63%) of 11 patients, magnetic resonance images showed symmetric hyperintensities in the basal ganglia in the T2- and proton-weighted sequence. In 4 of 11 cases the T2- and proton density-weighted images showed a pronounced signal increase confined to the gray matter of the occipital and visual cortex. Isolated atrophy of the visual cortex was noticeable in 2 of 11 cases. CONCLUSIONS: The clinical presentation of the Heidenhain variant of CJD was shown to correlate with the neuropathological findings of gliosis and nerve cell loss. In patients with visual disorders of unclear origin and signs of dementia, the differential diagnosis of a Heidenhain variant of CJD must be taken into consideration.

Adult↗
PubMed1999

Molecular genetics of human prion diseases in Germany.

Human prion diseases may be acquired as infectious diseases, they may be inherited in an autosomal dominant fashion or occur sporadically. Mutations and polymorphisms in the sequence of the coding region of the prion protein gene (PRNP) have been established as an important factor in all of these three types of prion diseases. Therefore, a total of 578 patients with suspect prion diseases referred to the German Creutzfeldt-Jakob disease (CJD) surveillance unit over a period of 4.5 years have been examined for mutations and polymorphisms in the coding region of PRNP. We found 40 cases with a missense mutation previously reported as pathogenic. Amongst these, the aspartate to asparagine change at codon 178 (D178N) was the most common mutation. All of these cases carried the D178N mutation in coupling with methionine at codon 129, resulting in the typical fatal familial insomnia (FFI) genotype. Most cases with pathogenic mutations were not found in the group of clinically "probable" cases according to established clinical criteria, supporting the notion that inherited prion diseases often exhibit atypical features. Two novel missense mutations (T188R and P238S) and several silent polymorphisms were found, demonstrating the quality of our screening procedure based on a modified version of the single-stranded conformational polymorphism technique. In "definite" CJD cases with no pathogenic mutation, the patients clinically classified as "probable" were mostly homozygous for methionine at the common polymorphism at codon 129, whereas there was a marked over-representation of patients homozygous for valine amongst those clinically classified as "possible". This large study on suspect cases of human prion diseases in Germany clearly shows that PRNP genetics is essential for a comprehensive analysis of prion diseases.

DNA↗
PubMed1999

The effect of stress on the onset and progression of Creutzfeldt-Jakob disease: results of a German pilot case-control study.

The association between Creutzfeldt-Jakob disease (CJD) and stressful life events was examined in a pilot case-control study in Germany. The study sample consisted of 37 CJD cases and 37 controls, both groups were frequency-matched for age and sex. In standardised interviews of close relatives of the cases and the controls, all stressful life events were assessed and subsequently grouped into one of the following three subgroups: psychosocial stress events, medical operations with hospitalisation, and other serious medical examinations. A significantly higher proportion of CJD cases experienced stressful life events during the last six months before disease onset than controls (65% vs. 32%, p = 0.01), yielding an odds ratio (OR) of 3.85 (95% confidence interval (CI): 1.33-11.30). We found the clearest distinction between cases and controls for the subgroup of medical operations where an OR of 6.97 (95% CI: 0.76-329.20) was observed. Further data indicated that stressful events seem to influence not only the onset of CJD but also the progression of the disease. Although based on a rather small study sample, this pilot case-control investigation suggests evidence that stressful life events in the last six months before disease onset may influence CJD occurrence and may modify the course of disease. This 'stress hypothesis', which is in line with findings from other epidemiological and experimental studies in CJD, is thus a promising direction for future CJD research as it could enlighten the pathophysiological mechanisms and point towards strategies for the prevention and therapy of CJD.

Age Distribution↗
PubMed1999

Isoform pattern of 14-3-3 proteins in the cerebrospinal fluid of patients with Creutzfeldt-Jakob disease.

Two-dimensional polyacrylamide gel electrophoresis of CSF has been used in the diagnosis of Creutzfeldt-Jakob disease (CJD). One of the two diagnostic protein spots was identified as isoform(s) of the 14-3-3 family of abundant brain proteins. This has led to the development of one-dimensional 14-3-3 sodium dodecyl sulfate polyacrylamide gel electrophoresis immunoblot, which is currently used to support the diagnosis of CJD. In the present study employing western blot analysis, we have identified the panel of 14-3-3 isoforms that appear in the CSF of 10 patients with CJD compared with 10 patients with other dementias. The results clearly show that the 14-3-3 isoforms beta, gamma, epsilon, and eta are present in the CSF of patients with CJD and can be used to differentiate other dementias. 14-3-3eta also gave a baseline signal in all patients with other dementias, including six patients with Alzheimer's disease. The presence of 14-3-3eta in the CSF of a patient with herpes simplex encephalitis was particularly noteworthy. This study has determined that isoform-specific 14-3-3 antibodies against beta, gamma, and epsilon should be considered for the neurochemical differentiation of CJD from other neurodegenerative diseases.

14-3-3 Proteins↗
PubMed1999

Late increase of serum S100 beta protein levels in hamsters after oral or intraperitoneal infection with scrapie.

Following recent reports of elevated serum S100 beta protein (S100 beta) levels in patients with genetic and sporadic Creutzfeldt-Jakob disease and in rodents parenterally infected with scrapie, the suitability of serum S100 beta as a preclinical marker for transmissible spongiform encephalopathies was assessed in time-course studies. Syrian hamsters were orally and intraperitoneally challenged with scrapie and assayed for serum S100 beta levels at various times after infection. Although elevated serum S100 beta levels were consistently observed in terminally ill animals for both routes of infection, the experiments failed to detect significantly increased S100 beta serum concentrations prior to the manifestation of clinical symptoms. Thus, in this animal model, serum S100 beta does not appear to be an appropriate marker for the preclinical detection of scrapie, but it may provide a convenient laboratory aid for the diagnosis of transmissible spongiform encephalopathy in naturally or accidentally infected animals and humans.

Administration, Oral↗
PubMed1999

How to improve the clinical diagnosis of Creutzfeldt-Jakob disease.

This paper describes a prospective follow-up of 364 patients initially notified as suspected Creutzfeldt-Jakob disease to a Surveillance Unit in Göttingen, Germany. Six patients were diagnosed as having genetic prion disease by blood analysis and were excluded from the study. After examination and review of the remaining 358, 193 were classified as probable Creutzfeldt-Jakob disease. However, autopsy revealed that five of the 193 did not have Creutzfeldt-Jakob disease (four cases, Alzheimer's disease; one case, cerebral lymphoma). Of the 54 patients classified as possible Creutzfeldt-Jakob disease, 10 had another diagnosis made at autopsy. Two of the 111 cases originally classified as having other diseases were found to have Creutzfeldt-Jakob disease on autopsy. Autopsy evidence, together with follow-up of the patients still living and those who died without autopsy, revealed a broad range of other diagnoses. In the younger age groups, the commonest were chronic inflammatory diseases including Hashimoto encephalitis, whilst rapidly progressive Alzheimer's disease was most common in the older age groups. The presence of 14-3-3 protein in the CSF discriminated better between Creutzfeldt-Jakob disease and other rapidly progressive dementias than did the EEG pattern or the MRI. The inclusion of this CSF protein in the criteria of Masters and colleagues (Ann Neurol 1979; 5: 177-88) improves the accuracy and confidence in the clinical diagnosis of Creutzfeldt-Jakob disease.

14-3-3 Proteins↗
PubMed1999

Hashimoto's encephalitis as a differential diagnosis of Creutzfeldt-Jakob disease.

OBJECTIVES: During an epidemiological study of Creutzfeldt-Jakob disease in Germany, Hashimoto's encephalitis was encountered as a differential diagnosis, which has not yet been described in this context. METHODS: The symptoms and findings of seven patients who fulfilled the criteria for "possible" Creutzfeldt-Jakob disease are presented. RESULTS: A Hashimoto's thyroiditis with antibodies against thyroglobulin or thyroid peroxidase, or both and a hypoechoic thyroid ultrasonogram were found in all cases. Analysis of CSF disclosed an increased leucocyte count in three patients, and a raised CSF:serum concentration ratio of albumin (QA1b) in four patients. The 14-3-3 protein, typical of Creutzfeldt-Jakob disease, could not be detected in any of our patients. No periodic sharp wave complexes, which are typical of Creutzfeldt-Jakob disease, were detected on EEG in any of the cases. By contrast with Creutzfeldt-Jakob disease, which leads to death within a few months, the patients with Hashimoto's encephalitis often recover quickly when treated adequately. All the patients improved after administration of corticosteroids. CONCLUSION: The clinical symptomatology of both diseases may be very similar: dementia, myoclonus, ataxia, and personality change or psychotic phenomena are characteristic symptoms.

Adult↗
PubMed1999

Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects.

Phenotypic heterogeneity in sporadic Creutzfeldt-Jakob disease (sCJD) is well documented, but there is not yet a systematic classification of the disease variants. In a previous study, we showed that the polymorphic codon 129 of the prion protein gene (PRNP), and two types of protease-resistant prion protein (PrP(Sc)) with distinct physicochemical properties, are major determinants of these variants. To define the full spectrum of variants, we have examined a series of 300 sCJD patients. Clinical features, PRNP genotype, and PrP(Sc) properties were determined in all subjects. In 187, we also studied neuropathological features and immunohistochemical pattern of PrP(Sc) deposition. Seventy percent of subjects showed the classic CJD phenotype, PrP(Sc) type 1, and at least one methionine allele at codon 129; 25% of cases displayed the ataxic and kuru-plaque variants, associated to PrP(Sc) type 2, and valine homozygosity or heterozygosity at codon 129, respectively. Two additional variants, which included a thalamic form of CJD and a phenotype characterized by prominent dementia and cortical pathology, were linked to PrP(Sc) type 2 and methionine homozygosity. Finally, a rare phenotype characterized by progressive dementia was linked to PrP(Sc) type 1 and valine homozygosity. The present data demonstrate the existence of six phenotypic variants of sCJD. The physicochemical properties of PrP(Sc) in conjunction with the PRNP codon 129 genotype largely determine this phenotypic variability, and allow a molecular classification of the disease variants.

Adult↗
PubMed1999

[Brain SPECT using Tc-99m-bicisate (ECD) in rapidly progressive dementia syndrome].

We present a 61-year-old male patient with progressive dementia. A brain SPECT with Tc-99m-bicisate was performed for confirmation of clinically suspected Alzheimer-dementia. At the time of the SPECT-investigation marked apraxia and aphasia besides severe dementia were present. Electrophysiological as well as anatomical neuroimaging findings showed non-diagnostic alterations. SPECT revealed distinct perfusion defects, which made Alzheimer Dementia unlikely. The further course of the patient was determined by rapidly progressive deterioration with development of akinetic mutism. Thereafter, increased levels of neuron-specific enolase as well as 14-3-3 proteins were found in the cerebro-spinal fluid (CSF). The patient finally died with signs of cerebral decortication. Due to the clinical course and the CSF-findings the patient's final diagnosis was Creutzfeldt-Jakob-disease, nevertheless no autopsy was performed. The presented case report underscores the clinical utility of perfusion brain SPECT in the differential diagnosis of dementias.

Brain↗
PubMed1999

Familial Creutzfeldt-Jakob disease with a novel 120-bp insertion in the prion protein gene

The clinical course, neuropathological features, and genetic findings in 3 members of a German family carrying a novel 120-bp insertion in the prion protein (PrP) gene are described. Genetic analysis of the mutated allele revealed a sequence of five extra octapeptide repeats, distinct from those of the two previously reported families with an insertion of this size. There was distinctive variation in the clinical course and the onset and duration of the illness in the documented subjects. Neuropathological evaluation showed neuronal loss and gliosis in the neocortex of the 3 examined cases; spongiform degeneration was found in 2 of them. PrP immunoreactivity of unusual morphology and distinct distribution was present in the cerebellum and neocortex ("blurred staining") of 2 examined cases. One subject showed features usually found in sporadic Creutzfeldt-Jakob disease with a punctate type of PrP deposition in the cerebellum. In addition, there were some plaque-like PrP aggregates morphologically similar to the other 2 cases in the molecular layer of the cerebellum, and unusual PrP immunoreactivity ("fleecy staining") was found in the neocortex. The clinicopathological heterogeneity in the documented family is in accordance with the phenotypic variability associated with previously reported insertions.

Journal Article↗