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Lymphocyte recruitment from blood into the lymph node is thought to be initiated by the presence of antigen. In this study, we have used lymphatic cannulation in sheep to demonstrate that the adjuvant ISCOMATRIX can induce dramatic lymph node activation in the absence of antigen. Consistent patterns of node shutdown (decreased output) and cell recruitment (increased output) with minimal blast cell responses were observed indicating that an antigen-specific immune response is not required. Production of IL-6, IL-8 and IFN-gamma, and the transient presence of red blood cells and neutrophils in the efferent lymph were associated with changes in efferent lymph cell trafficking. These early events may facilitate the screening of low frequency antigen-specific cells for binding to antigen and the subsequent amplification of the immune response.  相似文献   
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PURPOSE: To present a case of rapid and durable recovery of visual function in a patient with von Hippel-Lindau syndrome and optic nerve head hemangioblastoma after systemic treatment with the vascular endothelial growth factor (VEGF) receptor inhibitor SU5416. DESIGN: Interventional case report. METHODS: Visual function parameters, including visual acuity, automated visual field, and contrast sensitivity, were evaluated using standardized methods repeatedly over a 15-month period. Fundus photographs and fluorescein angiograms were also obtained. Central nervous system lesions were monitored by computed tomography (CT) and magnetic resonance imaging (MRI) scans. Treatment involved the systemic administration of the VEGF receptor inhibitor SU5416. MAIN OUTCOME MEASURES: Clinical presentation, visual acuity using Early Treatment Diabetic Retinopathy Study protocol, Humphrey automated perimetry, (Zeiss Humphrey Systems, Dublin, CA) Vistech contrast sensitivity (Vistech Consultants Inc., Dayton, OH) Farnsworth (Farnsworth-Munsell Color Services, New Windsor, NY) dichotomous panel D-15, retinal photography, fluorescein angiography, and CT and MRI scans. RESULTS: Within 4 weeks of therapy, visual acuity had improved from 20/32(-2) to 20/16(-1), the visual field had expanded from being circumferentially constricted to within 8 degrees of fixation to normal, and contrast sensitivity improved in all but the lowest spatial frequency (1.5 cycles/degree). No change was observed in lesion size by fundus photography. Improvement has been maintained over 18 months with intermittent SU5416 therapy. CONCLUSIONS: We report rapid, extensive, and durable recovery of visual function after systemic administration of the VEGF receptor inhibitor SU5416 to a patient with VHL syndrome and optic nerve head hemangioblastoma. These findings suggest that continued evaluation of VEGF inhibitors for ocular neovascular disorders is warranted.  相似文献   
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Branch vein occlusion is a significant cause of visual loss attributed to retinal vascular disease and is second only to diabetic retinopathy. BVO nearly always occurs at an AV crossing because of compression of the vein by the artery, resulting in hemodynamic abnormalities in the vein, including thrombus formation, reversal of flow toward the artery, and AV collateral formation. Relatively little information is available on the natural history of BVO; most of what exists is derived from clinical trials, including the BVOS. Current treatment options focus on treating sequelae of the occluded venous branch, such as macular edema, retinal neovascularization, vitreous hemorrhage, and traction retinal detachment. A novel therapeutic approach is decompression of the AV crossing, which has had promising initial results including restoration of vision and reversal of hemodynamic abnormalities. A prospective, controlled, clinical trial is being organized to determine the role of AV sheathotomy in the treatment of BVO.  相似文献   
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Following its binding to somatodendritic receptors, the neuropeptide neurotensin (NT) internalizes via a clathrin-mediated process. In the present study, we investigated whether NT also internalizes presynaptically using synaptosomes from rat neostriatum, a region in which NT1 receptors are virtually all presynaptic. Binding of [3H]–NT to striatal synaptosomes in the presence of levocabastine to block NT2 receptors is specific, saturable, and has NT1 binding properties. A significant fraction of the bound radioactivity is resistant to hypertonic acid wash indicating that it is internalized. Internalization of [3H]–NT, like that of [125I]–transferrin, is blocked by sucrose and low temperature, consistent with endocytosis occurring via a clathrin-dependent pathway. However, contrary to what was reported at the somatodendritic level, neither [3H]–NT nor [125I]–transferrin internalization in synaptosomes is sensitive to the endocytosis inhibitor phenylarsine oxide. Moreover, treatment of synaptosomes with monensin, which prevents internalized receptors from recycling to the plasma membrane, reduces [3H]–NT binding and internalization, suggesting that presynaptic NT1 receptors, in contrast to somatodendritic ones, are recycled back to the plasma membrane. Taken together, these results suggest that NT internalizes in nerve terminals via an endocytic pathway that is related to, but is mechanistically distinct from that responsible for NT internalization in nerve cell bodies.  相似文献   
107.
Quality of life in psychogenic nonepileptic seizures   总被引:3,自引:1,他引:2  
PURPOSE: Psychogenic nonepileptic seizures (PNESs) are events that alter or seem to alter the neurologic function and, in their appearance, resemble epileptic seizures (ESs). In patients with ESs the psychological and medical aspects of epilepsy greatly influence the health-related quality of life (HRQOL). The relation between these factors and PNESs is not well established. In this study, we compared HRQOL in patients with PNESs with that of patients with ESs. METHODS: We evaluated 105 patients admitted to the Epilepsy Monitoring Unit of University Hospital between January 20, 2001, and January 20, 2002. Only patients with the definite diagnosis of ESs or PNESs were analyzed (n = 85). Patients completed an epilepsy-specific quality-of-life instrument (QOLIE-89), the Profile of Mood States (POMS), and Adverse Events Profile (AEP). We used t tests and regression analyses to contrast HRQOL in PNESs and ESs and to elucidate the main factors associated with HRQOL in patients with PNESs. RESULTS: In our sample, 45 patients had PNESs, and 40 had ESs. The overall HRQOL and scores on 13 of 19 QOLIE-89 subscales were significantly lower (i.e., worse) in PNES than in ES patients. AEP and scores on five of six POMS subscales also were worse in PNES patients than in ES patients. PNES versus ES diagnosis, POMS depression/dejection, and AEP were significant predictors of HRQOL, jointly explaining 65% variation in HRQOL. The lower HRQOL in PNESs versus ESs was in part explained by depression and AEP. CONCLUSIONS: Patients with PNESs have a lower HRQOL and worse mood problems than do patients with ESs. This disadvantage is primarily due to depression and medication side effects, although these factors influence QOL in much the same way in PNES and ES patients. These baseline HRQOL data on patients with PNESs can be used to evaluate the effects of treatment in this patient population.  相似文献   
108.
OBJECTIVE: To examine the association between prenatal exposure to poliovirus infection and later development of schizophrenia or affective psychosis in a Southern Hemisphere psychiatric register. METHODS: We calculated rates of poliomyelitis cases per 10 000 background population and rates for schizophrenia(n = 6078) and affective psychosis (n = 3707)per 10 000 births for the period 1930-1964. Empirically weighted regression was used to measure the association between a given psychosis birth-rate and a poliomyelitis epidemic during gestation. RESULTS: There was no statistically significant association between exposure to a poliomyelitis epidemic during gestation and subsequent development of schizophrenia or affective psychosis. CONCLUSIONS: The lack of a consistent statistically significant association between poliovirus epidemics and schizophrenia suggests that either poliovirus may have a small effect which is only detectable with large data-sets and/or the effect may be modified by location. Further investigation of such inconsistencies may help elucidate candidate risk-modifying factors for schizophrenia.  相似文献   
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