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OBJECT: Medically refractory dystonia has recently been treated using deep brain stimulation (DBS) targeting the globus pallidus internus (GPI). Outcomes have varied depending on the features of the dystonia. There has been limited literature regarding outcomes for refractory dystonia following DBS of the subthalamic nucleus (STN). METHODS: Four patients with medically refractory, predominantly cervical dystonia underwent STN DBS. Intraoperative assessments with the patients in a state of general anesthesia were performed to determine the extent of fixed deformities that might predict outcome. Patients were rated using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) preoperatively and 3 and 12 months following surgery by a rater blinded to the study. Mean changes and standard errors of the mean in scores were calculated for each subscore of the two scales. Scores were also analyzed using analysis of variance and probability values were generated. Neuropsychological assessments and quality of life ratings using the 36-Item Short Form Health Survey (SF-36) were evaluated longitudinally. RESULTS: Significant improvements were seen in motor (p = 0.04), disability (p = 0.02), and total TWSTRS scores (p = 0.03). Better outcomes were seen in those patients who did not have fixed deformities. There was marked improvement in the mental component score of the SF-36. Neuropsychological function was not definitively impacted as a result of the surgery. CONCLUSIONS: Deep brain stimulation of the STN is a novel target for dystonia and may be an alternative to GPI DBS. Further studies need to be performed to confirm these conclusions and to determine optimal candidates and stimulation parameters.  相似文献   
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Both clinical experience and a growing medical literature indicate that some persons who have been exposed to human immunodeficiency virus (HIV) infection remain uninfected. Although in some instances this may represent good fortune, cohorts of uninfected persons have been reported who are considered at high risk for infection. In these cohorts a variety of characteristics have been proposed as mediating protection, but to date only the 32–base pair deletion in the chemokine (C‐C motif) receptor 5 gene, which results in complete failure of cell surface expression of this coreceptor, has been associated with high‐level protection from HIV infection. With this in mind, there are probably many other factors that may individually or in combination provide some level of protection from acquisition of HIV infection. Because some of these factors are probably incompletely protective or inconsistently active, identifying them with confidence will be difficult. Nonetheless, clarifying the determinants of protection against HIV infection is a high priority that will require careful selection of high‐risk uninfected cohorts, who should undergo targeted studies of plausible mediators and broad screening for unexpected determinants of protection.  相似文献   
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OBJECTIVE: This brief report presents a staff training program based on psychiatric rehabilitation principles used in a hospital setting. The training program intervention significantly promoted the belief that mental illness does not necessarily limit functioning and also improved awareness of research findings, evidence-based practices and community services. METHODS: A randomized controlled study assessed the impact of the program on the staff's attitudes regarding psychiatric rehabilitation and recovery. RESULTS: Findings suggest that in-service training programs within a hospital setting can change staff attitudes in order to support psychiatric rehabilitation. CONCLUSIONS: A psychiatric rehabilitation forum, made up of representatives from all disciplines, including the medical directors of every ward, was set up in the hospital following the training program and has become the main avenue to disseminate information, messages, and goals to the staff at large and to the hospital administration. It is the forum that creates the shared vision about psychiatric rehabilitation within the hospital and has the task of facilitating implementation of services according to that vision.  相似文献   
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Detection of cortical laminar architecture using manganese-enhanced MRI   总被引:1,自引:0,他引:1  
Changes in manganese-enhanced MRI (MEMRI) contrast across the rodent somatosensory cortex were compared to the cortical laminae as identified by tissue histology and administration of an anatomical tracer to cortex and thalamus. Across the cortical thickness, MEMRI signal intensity was low in layer I, increased in layer II, decreased in layer III until mid-layer IV, and increased again, peaking in layer V, before decreasing through layer VI. The reeler mouse mutant was used to confirm that the cortical alternation in MEMRI contrast was related to laminar architecture. Unlike in wild-type mice, the reeler cortex showed no appreciable changes in MEMRI signal, consistent with absence of cortical laminae in histological slides. The tract tracing ability of MEMRI was used to further confirm assignments and demonstrate laminar specificity. Twelve to 16 h after stereotaxic injections of MnCl(2) to the ventroposterior thalamic nuclei, an overall increase in signal intensity was detected in primary somatosensory cortex compared to other brain regions. Maximum intensity projection images revealed a distinctly bright stripe located 600-700 microm below the pial surface, in layer IV. The data show that both systemic and tract tracing forms of MEMRI are useful for studying laminar architecture in the brain.  相似文献   
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Traumatic brain injury (TBI) remains a frequent and major challenge in neurological and neurosurgical practice. Apoptosis may play a role in cerebral tissue damage induced by the traumatic insult, and thus its detection and inhibition may advance patient care. DDC (N,N'-didansyl-L-cystine) is a novel fluorescent probe for detection of apoptotic cells. We now report on the performance of DDC in experimental TBI. Closed head injury was induced in mice by weight-drop. DDC was administered intravenously in vivo. Two hours later, animals were sacrificed, and brain tissue was subjected to fluorescent microcopy, for assessment of DDC uptake, in correlation with histopathological assessment of apoptosis by TUNEL and caspase substrates, and also in correlation with the neurological deficits, as assessed by Neurological Severity Score (NSS). Selective uptake of DDC was observed at the primary site of injury, and also at remote sites. Uptake was at the cellular level, with accumulation of DDC in the cytoplasm. Cells manifesting DDC uptake were confirmed as apoptotic cells by detection of the characteristic apoptotic DNA fragmentation (positive TUNEL staining) and detection of activated caspases. The damaged region stained by DDC fluorescence correlated with the severity of neuronal deficits. Our study confirms the role of apoptosis in TBI, and proposes DDC as a useful tool for its selective targeting and detection in vivo. Such imaging of apoptosis, following future radiolabeling of DDC, may advance care for patients with head injury, by allowing real-time evaluation of the extent of tissue damage, assessment of novel therapeutic strategies, and optimization of treatment for the individual patient.  相似文献   
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Traumatic brain injury activates N-methyl-d-aspartate receptors (NMDAR) inducing activation of the Ras protein (a key regulator of cell growth, survival, and death) and its effectors. Thus, trauma-induced increase in active Ras-GTP might contribute to traumatic brain injury pathology. Based on this hypothesis, a new concept of neuroprotection is proposed, examined here by investigating the effect of the Ras inhibitor S-trans, trans-farnesylthiosalicylic acid (FTS) in a mouse model of closed head injury (CHI). Mice subjected to CHI were treated systemically 1 h later with FTS (5 mg/kg) or vehicle. After 1 h, Ras-GTP in the contused hemisphere showed a significant (3.8-fold) increase, which was strongly inhibited by FTS (82% inhibition) or by the NMDA-receptor antagonist MK-801 (53%). Both drugs also decreased active (phosphorylated) extracellular signal-regulated kinase. FTS prevented the CHI-induced reduction in NMDAR binding in cortical, striatal, and hippocampal regions, measured by [3H]-MK-801 autoradiography, and decreased lesion size by 50%. It also reduced CHI-induced neurologic deficits, indicated by the highly significant (P < 0.0001) 60% increase in extent of recovery. Thus, FTS provided long-term neuroprotection after CHI, rescuing NMDAR binding in the contused hemisphere and profoundly reducing neurologic deficits. These findings suggest that nontoxic Ras inhibitors such as FTS may qualify as neuroprotective drugs.  相似文献   
50.
Aberrant Ras pathway functions contribute to the malignant phenotype of lung cancers. Inhibitors of Ras might therefore be considered as potential drugs for lung cancer therapy. Here, we show that the Ras inhibitor farnesylthiosalicylic acid (salirasib) inhibits proliferation of human lung cancer cells harboring a mutated K-ras gene (A549, H23, or HTB54) or overexpressing a growth factor receptor (H1299 or HTB58) and enhances the cytotoxic effect of the chemotherapeutic drug gemcitabine. Salirasib inhibited active K-Ras in A549 cells, reversed their transformed morphology, and inhibited their anchorage-independent growth in vitro. Tumor growth in A549 and HTB58 cell nude mouse models was inhibited by i.p. administration of salirasib. P.o. formulated salirasib also inhibited A549 cell tumor growth. Our results suggest that p.o. salirasib may be considered as a potential treatment for lung cancer therapy.  相似文献   
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