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61.
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Autosomal-dominant spinocerebellar ataxia type 1 (SCA1) is an adult-onset progressive disorder with well-characterized neurodegeneration in the cerebellum and brainstem. The objective of this study is to evaluate neurochemical changes associated with neurodegeneration in cerebral tissue in SCA1 patients compared to age- and gender-matched healthy controls. Nine patients with genetically proven SCA1 and nine gender- and age-matched healthy controls were prospectively recruited from the ataxia clinic and received clinical examination. A 1.5 T single-voxel brain proton MR spectroscopy was performed for total N-acetyl aspartate (tNAA) in cerebellum, parietofrontal lobe white matter, sensory cortex, and visual cortex. In the patients, tNAA was severely decreased in the cerebellar voxel; however, in the voxels positioned in sensory cortex, parietofrontal lobe white matter and visual cortex tNAA was reduced in comparison to controls. In addition to the profoundly affected cerebellum, we also found evidence for cerebral neurodegeneration in parietal lobe white matter, sensory cortex, and visual cortex in SCA1 patients illustrating a multisystem neurodegenerative character of the disease.  相似文献   
64.
The term frontotemporal lobar degeneration (FTLD) refers to a group of neurodegenerative disorders that target the frontal and temporal lobes. It accounts for approximately 10 % of pathologically confirmed dementias but has been demonstrated to be as prevalent as Alzheimer’s disease in patients below the age of 65. The 3 major clinical syndromes associated with FTLD include behavioral variant frontotemporal dementia, semantic and nonfluent variants of primary progressive aphasia. The more recently introduced term logopenic variant appears to represent an atypical form of Alzheimer’s disease in the majority of cases. The neuropathology underlying these clinical syndromes is very heterogeneous and does not correlate well with the clinical phenotype. This causes great difficulties in early and reliable diagnosis and treatment of FTLD. However, significant advances have been made in recent years via the application of magnetic resonance imaging and positron emission tomography imaging methods as biomarkers. The current review aims to provide a synopsis on the value of magnetic resonance imaging-based and molecular imaging procedures in FTLD.  相似文献   
65.

BACKGROUND

Calciphylaxis, a rare disease seen in chronic dialysis patients, is associated with significant morbidity and mortality. As is the case with other rare diseases, the precise epidemiology of calciphylaxis remains unknown. Absence of a unique International Classification of Diseases (ICD) code impedes its identification in large administrative databases such as the United States Renal Data System (USRDS) and hinders patient-oriented research. This study was designed to develop an algorithm to accurately identify cases of calciphylaxis and to examine its incidence and mortality.

DESIGN, PARTICIPANTS, AND MAIN MEASURES

Along with many other diagnoses, calciphylaxis is included in ICD-9 code 275.49, Other Disorders of Calcium Metabolism. Since calciphylaxis is the only disorder listed under this code that requires a skin biopsy for diagnosis, we theorized that simultaneous application of code 275.49 and skin biopsy procedure codes would accurately identify calciphylaxis cases. This novel algorithm was developed using the Partners Research Patient Data Registry (RPDR) (n?=?11,451 chronic hemodialysis patients over study period January 2002 to December 2011) using natural language processing and review of medical and pathology records (the gold-standard strategy). We then applied this algorithm to the USRDS to investigate calciphylaxis incidence and mortality.

KEY RESULTS

Comparison of our novel research strategy against the gold standard yielded: sensitivity 89.2 %, specificity 99.9 %, positive likelihood ratio 3,382.3, negative likelihood ratio 0.11, and area under the curve 0.96. Application of the algorithm to the USRDS identified 649 incident calciphylaxis cases over the study period. Although calciphylaxis is rare, its incidence has been increasing, with a major inflection point during 2006–2007, which corresponded with specific addition of calciphylaxis under code 275.49 in October 2006. Calciphylaxis incidence continued to rise even after limiting the study period to 2007 onwards (from 3.7 to 5.7 per 10,000 chronic hemodialysis patients; r?=?0.91, p?=?0.02). Mortality rates among calciphylaxis patients were noted to be 2.5–3 times higher than average mortality rates for chronic hemodialysis patients.

CONCLUSIONS

By developing and successfully applying a novel algorithm, we observed a significant increase in calciphylaxis incidence. Because calciphylaxis is associated with extremely high mortality, our study provides valuable information for future patient-oriented calciphylaxis research, and also serves as a template for investigating other rare diseases.
  相似文献   
66.
The application of viral vectors for gene expression and delivery is rapidly evolving, with several entering clinical trials. However, a number of issues, including safety, gene expression levels, cell selectivity and antivector immunity, are driving the search for new vector systems. A number of replicon-based vectors derived from positive-strand RNA viruses have recently been developed, and this paper reviews the current knowledge on the first flavivirus replicon system, which is based on the Australian flavivirus Kunjin (KUN). Like most replicon systems, KUN replicons can be delivered as DNA, RNA or virus-like particles, they replicate their RNA in the cytoplasm and direct prolonged high-level gene expression. However, unlike most alphavirus replicon systems, KUN replicons are non-cytopathic, with transfected cells able to divide, allowing the establishment of cell lines stably expressing replicon RNA and heterologous genes. As vaccine vectors KUN replicons can induce potent, long-lived, protective, immunogen-specific CD8+ T cell immunity, a feature potentially related to extended production of antigen and double-stranded RNA-induced 'danger signals'. The identification of KUN replicon mutants that induce increased levels of IFN-alpha/beta has also spawned investigation of KUN replicons for use in cancer gene therapy. The unique characteristics of KUN replicons may thus make them suitable for specific protein production, vaccine and gene therapy applications.  相似文献   
67.
Targeting stathmin in prostate cancer   总被引:4,自引:0,他引:4  
Stathmin is the founding member of a family of microtubule-destabilizing proteins that regulate the dynamics of microtubule polymerization and depolymerization. Stathmin is expressed at high levels in a variety of human cancers and provides an attractive molecule to target in cancer therapies that disrupt the mitotic apparatus. We developed replication-deficient bicistronic adenoviral vectors that coexpress green fluorescent protein and ribozymes that target stathmin mRNA. The therapeutic potential of these recombinant adenoviruses was tested in an experimental androgen-independent LNCaP prostate cancer model. Adenovirus-mediated transfer of anti-stathmin ribozymes resulted in efficient transduction and marked inhibition of stathmin expression in these cells. Cells that were transduced with the anti-stathmin adenoviruses showed a dramatic dose-dependent growth inhibition. This was associated with accumulation of LNCaP cells in the G2-M phases of the cell cycle. A similar dose-dependent inhibition of clonogenic potential was also observed in cells infected with anti-stathmin adenoviruses. Morphologic and biochemical analysis of infected cells showed a marked increase in apoptosis characterized by detachment of the cells, increased chromatin condensation, activation of caspase-3, and fragmentation of internucleosomal DNA. If these findings are confirmed in vivo, it may provide an effective approach for the treatment of prostate cancer.  相似文献   
68.
The importance of needs assessment for service development has been widely recognized. In this study we examined the agreement between the Camberwell Assessment of Need Short Appraisal Schedule self-report version (CANSAS-P) and the Camberwell Assessment of Need interview-based scale in 100 outpatients with schizophrenia and schizoaffective disorders. We found equivalent number of met, unmet, and no needs for most of the domains of the two instruments. Both intraclass correlations and Kappa reliability coefficients were high for most need domains. The high agreement between the two instruments suggests that the CANSAS-P can be used as a screening tool to detect unmet needs in both clinical routine practice and research surveys in mental health outpatient settings.  相似文献   
69.

Purpose

This study aims to identify whether selected patient and ward-related factors are associated with the use of coercive measures. Data were collected as part of the EUNOMIA international collaborative study on the use of coercive measures in ten European countries.

Methods

Involuntarily admitted patients (N = 2,027) were divided into two groups. The first group (N = 770) included patients that had been subject to at least one of these coercive measures during hospitalization: restraint, and/or seclusion, and/or forced medication; the other group (N = 1,257) included patients who had not received any coercive measure during hospitalization. To identify predictors of use of coercive measures, both patients’ sociodemographic and clinical characteristics and centre-related characteristics were tested in a multivariate logistic regression model, controlled for countries’ effect.

Results

The frequency of the use of coercive measures varied significantly across countries, being higher in Poland, Italy and Greece. Patients who received coercive measures were more frequently male and with a diagnosis of psychotic disorder (F20–F29). According to the regression model, patients with higher levels of psychotic and hostility symptoms, and of perceived coercion had a higher risk to be coerced at admission. Controlling for countries’ effect, the risk of being coerced was higher in Poland. Patients’ sociodemographic characteristics and ward-related factors were not identifying as possible predictors because they did not enter the model.

Conclusions

The use of coercive measures varied significantly in the participating countries. Clinical factors, such as high levels of psychotic symptoms and high levels of perceived coercion at admission were associated with the use of coercive measures, when controlling for countries’ effect. These factors should be taken into consideration by programs aimed at reducing the use of coercive measures in psychiatric wards.  相似文献   
70.
The ability to inhibit action tendencies is vital for adaptive human behaviour. Various paradigms are supposed to assess action inhibition and are often used interchangeably. However, these paradigms are based on different conceptualizations (action restraint vs. action cancellation) and the question arises as to what extent different conceptualizations of inhibitory processing are mirrored in a distinct neural activation pattern. We used functional magnetic resonance imaging to investigate the neural correlates of action restraint vs. action cancellation. Analyses of local activity changes as well as network connectivity measures revealed a strong overlap of activation within a common action inhibition network including inferior frontal, pre‐supplementary motor and thalamic brain areas as well as the anterior cingulate cortex. Furthermore, our findings pointed to additional neural networks that are distinct for action restraint (i.e. right superior frontal gyrus, left middle frontal gyrus, and bilateral anterior cingulate cortex) and action cancellation (i.e. right middle frontal gyrus, posterior cingulate cortex, and parietal regions). Our connectivity analyses showed that different inhibitory modalities largely relied on a task‐independent global inhibition network within the brain. Furthermore, they suggested that the conceptually distinct inhibitory aspects of action restraint vs. action cancellation also activated additional specific brain regions in a task‐dependent manner. This has implications for the choice of tasks in an empirical setting, but is also relevant for various clinical contexts in which inhibition deficits are considered a diagnostic feature.  相似文献   
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