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All Borna disease virus (BDV) sequences derived from human specimens published till date were thoroughly analysed and compared to sequences of BDV laboratory strains and to BDV sequences from animals which succumbed to classical Borna disease (BD). Despite high sequence conservation of the BDV genome, animal-derived BDV sequences clustered according to their geographic origin. However, in marked contrast, human-derived BDV sequences did not cluster according to their geographic origin but showed high sequence identities to BDV laboratory strains and animal-derived BDVs handled in the laboratories reporting the human strains. Japanese, US, Australian and French human-derived BDV sequences proved to be identical or very similar to animal-derived BDV sequences from Germany, although the human specimens were collected hundreds to thousands of miles away from the central European BD endemic regions. These findings suggest that previous studies linking BDV to human neuropsychiatric disease may have been compromised by inadvertent sample contamination.  相似文献   
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In previous studies, we have demonstrated a number of cytogenetic alterations in granulosa cell tumors (GCTs), especially on chromosomes X, 12, 14, and 22. However, little is known about specific loci on 14q, which could play an important role in tumor pathology. Therefore, we assessed four important genes in 30 GCTs using fluorescence-in situ-hybridization (FISH). Comparative genomic hybridization (CGH) was performed on paraffin-embedded material. Then, we applied FISH with gene-specific DNA probes for AKT1 (14q32.32), FOS (14q24.3), BCL2L2 (14q11.2-q12), and TGFbeta3 (14q24), and tried to find a correlation between CGH, FISH, tumor stage, and survival. In CGH, 7 of 30 cases (23.3%) showed complete gains on chromosome 14. FISH of the four loci revealed gains of hybridization signals in 8 of 30 cases (26.6%), indicating trisomy of the whole chromosome arm. The same aberration was detected by FISH in 2 of 30 cases (6.6%), which were negative using CGH. One case (1 of 30; 3.3%) was found to have a gain on chromosome 14 by CGH, which could not be confirmed by FISH. A correlation with tumor stage or survival could not be established. Our results suggest that GCTs may be characterized by trisomy of chromosome 14. A specific oncogene that could play a particular role in the tumorigenesis of GCTs was not identified on chromosome 14.  相似文献   
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OBJECTIVES: Recent studies investigating the association of DNA variants in the metabotropic glutamate receptor gene (GRM3) with schizophrenia susceptibility revealed conflicting results. In this study, we focused on DNA sequence variants, for which association was reported and attempted to replicate association with schizophrenia or with cognitive deficits known to be present in patients with schizophrenia. METHODS: A sample of 242 families with affected offspring and five single nucleotide markers located in the genomic region of GRM3 has been used to replicate association with schizophrenia. In addition, results of neuropsychological tests, trail making test B and the Stroop color-naming task were available for a subgroup of these families (N=88) and an independent sample of 148 patients with schizophrenia. Correlation of these measurements with genotypic data was performed using analysis of variance. RESULTS: No statistical evidence for association with schizophrenia or correlation with cognitive deficits as measured by the trail making test B or the Stroop color-naming task and the five DNA sequence variants could be detected. A trend towards association with schizophrenia was revealed for a single marker (rs2237562, P=0.056) and for 2-marker and 3-marker haplotypes containing this variant. CONCLUSIONS: Our study of DNA sequence variants in the GRM3 gene did not provide further support for genetic association with schizophrenia or for correlation with cognitive deficits.  相似文献   
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Laser microdissection combined with real-time RT-PCR presents an advanced tool to quantify particular RNA species in defined tissue areas. Dealing with infectious tissue samples increases the need to overcome the risk of infectivity and contamination during laser microdissection. Here, an useful method to control infectivity of frozen brain sections infected with the Borna disease virus (BDV), an enveloped RNA virus, is described. Various pre-treatments were applied prior to laser microdissection and subsequent real-time RT-PCR. Brain sections were incubated with Vennotrade mark Vet 1 super 1% or 70% ethanol for 30, 60 and 90min, followed by quantification of infectious virus and RNA recovery using laser microdissection. Total RNA specific for the BDV nucleoprotein (BDV-N) and the cellular genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), succinate-ubiquinone reductase (SDHA) and hypoxanthine phosphoribosyl-transferase-1 (HPRT) was measured by real-time RT-PCR and compared to BDV-infected control samples. After 30 min incubation with both disinfectants, no infectious virus was isolated, while sufficient cDNA copy numbers were amplified. As tissue morphology was best preserved after ethanol treatment, 30min incubation with 70% ethanol was selected as the method of choice to prevent infectivity of BDV. This procedure represents a suitable pre-treatment option to ensure adequate safety of virus infected central nervous system tissue.  相似文献   
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Introduction Women with a pathogenic BRCA1/2 mutation have a markedly increased lifetime risk of developing breast and/or ovarian cancer. The current preventive treatment alternatives that are offered are an intensified breast cancer screening programme and risk-reducing operations. Before deciding on one option, medical and personal factors such as life situation and individual preferences must be weighed carefully. Decision aids are used internationally to support BRCA1/2 mutation carriers during their decision-making process. In this study these are analysed structurally for the first time and their applicability to the German context is examined. Material and Methods A systematic literature search in five electronic databases and a manual search were performed. The identified decision aids were evaluated with regard to formal criteria, medical content and quality. The qualitative assessment used the criteria of the International Patient Decision Aid Standards Collaboration (IPDASi v4.0), which examined various dimensions (e.g., information, probabilities, values). Results Twenty decision aids, which were published between 2003 and 2019 in Australia (n = 4), the United Kingdom (n = 3), Canada (n = 2), the Netherlands (n = 2) and the USA (n = 9), were included. Nine focus on BRCA1/2 mutation carriers and eleven include other risk groups. Eighteen include risk-reducing operations as decision options, 14 list screening methods for breast and/or ovarian cancer, and 13 describe the possibility of pharmacological prevention by means of selective oestrogen receptor modulators or aromatase inhibitors. Nine of the 20 decision aids meet fundamental quality criteria (IPDASi v4.0 qualification criteria). Conclusion International decision aids can serve formally as a basis for a German decision aid for BRCA1/2 mutation carriers. Some of them differ markedly in content from the recommendations of German guidelines. Only a few achieve a high quality. Key words: BRCA1, BRCA2, decision aid, familial breast cancer, familial ovarian cancer  相似文献   
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Magnetic resonance imaging is an excellent noninvasive method for evaluating thoracic aortic dissections. A variety of magnetic resonance scans of aortic dissections are shown, documenting the ability of magnetic resonance to image the true lumen, the false channel, and the intimal septum. Detail is provided on magnetic resonance imaging techniques and findings.  相似文献   
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To identify clinical and Doppler echocardiographic correlates of instability with the onset of atrial fibrillation (AF), 87 consecutive patients with new-onset AF who had echocardiograms recorded during that hospital admission while in sinus rhythm were studied. Reviewers who were blinded to echocardiographic and Doppler data classified 51 patients (59%) as unstable because of the development of angina, congestive heart failure, syncope or hypotension with the onset of AF. Echocardiographic and Doppler data on transmitral blood flow velocity were analyzed by a single reviewer who was blinded to other clinical data. Multiple logistic regression analysis identified 3 variables as independent predictors of clinical instability with the onset of AF: (1) history of prior myocardial infarction (p less than 0.02); (2) echocardiographic evidence of left ventricular dysfunction (p less than 0.03); and (3) Doppler evidence of increased atrial filling fraction (p less than 0.0001). An atrial filling fraction threshold of 0.40 had a sensitivity for predicting clinical instability of 80% and a specificity of 72%. These data are consistent with the hypothesis that patients who are more dependent on the atrial contribution to ventricular filling are at increased risk of instability with AF due to the loss of atrial systole.  相似文献   
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