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1.
To enhance the efficacy of cellular immunotherapy for gliomas, we tested the concept of using proinflammatory cytokine treatment with interferon-gamma (IFN-gamma) or interleukin-1beta (IL-1beta) or both to render glioma cells more susceptible to cytolysis by alloreactive cytotoxic T lymphocytes (aCTL). The cytokines, separately or in combination, were able to upregulate major histocompatibility complex (MHC) class I antigen or intercellular adhesion molecule-1 (ICAM-1) on Fischer rat 9L gliosarcoma cells. 9L cells were incubated in vitro for 24, 48, or 72 h with varying concentrations of rat IFN-gamma (0-2000 U/ml) or recombinant human IL-1 (rHUIL-1) (0-1000 U/ml) or both. By 48 h, IFN-gamma (500 U/ml) maximally induced the percentage of positive expressing cells and the relative antigen density of MHC class I and ICAM-1 on 9L cells, whereas IL-1 induced only ICAM-1 expression. Simultaneous incubation of IL-1 with IFN-gamma did not further affect the induction of class I on 9L cells more than that achieved with IFN-gamma alone. 9L cells with upregulated MHC class I and ICAM-1 expression were more sensitive to lysis by aCTL in in vitro cytotoxicity assays, regardless of whether the precursor aCTL came from naive or from 9L-immunized rats. Furthermore, inhibition of 9L cytotoxicity in assays that included blocking antibodies to MHC class I or to ICAM-1 revealed that T cell receptor (TCR) interactions with MHC class I and that ICAM-1 interactions with lymphocyte function-associated-1 (LFA-1) antigen account for a portion of the glioma lysis by aCTL.  相似文献   
2.
Characterization of FMR1 proteins isolated from different tissues   总被引:1,自引:5,他引:1  
FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(67–80 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (39–41kDa) were found, which had the same N terminus as the 67–90kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied.  相似文献   
3.
Exerting its actions pre-, post- and peri-synaptically, brain-derived neurotrophic factor (BDNF) is one of the most potent modulators of hippocampal synaptic function. Here, we examined the effects of BDNF on a rapidly recycling pool (RRP) of vesicles within excitatory synapses. First, we estimated vesicular release in hippocampal cultures by performing FM4-64 imaging in terminals impinging on enhanced green fluorescent protein (eGFP)-labelled dendritic spines – a hallmark of excitatory synapses. Consistent with a modulation of the RRP, BDNF increased the evoked destaining rate of FM4-64 only during the initial phase of field stimulation. Multiphoton microscopy in acute hippocampal slices confirmed these observations by selectively imaging the RRP, which was loaded with FM1-43 by hyperosmotic shock. Slices exposed to BDNF showed an increase in the evoked and spontaneous rates of FM1-43 destaining from terminals in CA1 stratum radiatum, mostly representing excitatory terminals of Schaffer collaterals. Variance-mean analysis of evoked EPSCs in CA1 pyramidal neurons further confirmed that release probability is increased in BDNF-treated slices, without changes in the number of independent release sites or average postsynaptic quantal amplitude. Because BDNF was absent during dye loading, imaging, destaining and whole-cell recordings, these results demonstrate that BDNF induces a long-lasting enhancement in the probability of transmitter release at hippocampal excitatory synapses by modulating the RRP. Since the endogenous BDNF scavenger TrkB-IgG prevented the enhancement of FM1-43 destaining rate caused by induction of long-term potentiation in acute hippocampal slices, the modulation of a rapidly recycling vesicle pool may underlie the role of BDNF in hippocampal long-term synaptic plasticity.  相似文献   
4.
Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset movement disorder affecting FMR1 premutation carriers, is associated with cerebral and cerebellar lesions. The aim of this study was to test whether computational anatomy can detect similar patterns in asymptomatic FMR1 premutation carriers (mean age 46.7 years) with qualitatively normal -appearing grey and white matter on brain MRI. We used a multimodal imaging protocol to characterize brain anatomy by automated assessment of gray matter volume and white matter properties. Structural changes in the hippocampus and in the cerebellar motor network with decreased gray matter volume in lobule VI and white matter alterations of the corresponding afferent projections through the middle cerebellar peduncles are demonstrated. Diffuse subcortical white matter changes in both hemispheres, without corresponding gray matter alterations, are only identified through age × group interactions. We interpret the hippocampal fimbria and cerebellar changes as early alterations with a possible neurodevelopmental origin. In contrast, progression of the diffuse cerebral hemispheric white matter changes suggests a neurodegenerative process, leading to late-onset lesions, which may mark the imminent onset of FXTAS.  相似文献   
5.
Ear advantage during a dichotic listening task tends to mirror speech lateralization. Previous studies in stroke patients have shown that lesions in the dominant hemisphere often seem to produce changes in ear advantage. In this study six Parkinson’s disease (PD) patients treated for motor symptoms with deep brain stimulation (DBS) of the left subthalamic nucleus (STN) were tested preoperatively and at approximately 6 and 18 months postoperatively with a dichotic listening task. Results show a significant decline of the right ear advantage over time. In three of the patients a right ear advantage preoperativley changed to a left ear advantage 18 months postoperatively. This suggests the possibility that additional longitudinal studies of this phenomenon could serve as a model for understanding changes in indirect measures of speech lateralization in stroke patients.  相似文献   
6.
ObjectiveTo evaluate the effects of bilateral caudal zona incerta (cZi) deep brain stimulation (DBS) for Parkinson's disease (PD) one year after surgery and to create anatomical improvement maps based on patient-specific simulation of the electric field.Materials and MethodsWe report the one-year results of bilateral cZi-DBS in 15 patients with PD. Patients were evaluated on/off medication and stimulation using the Unified Parkinson's Disease Rating Scale (UPDRS). Main outcomes were changes in motor symptoms (UPDRS-III) and quality of life according to Parkinson's Disease Questionnaire-39 (PDQ-39). Secondary outcomes included efficacy profile according to sub-items of UPDRS-III and simulation of the electric field distribution around the DBS lead using the finite element method. Simulations from all patients were transformed to one common magnetic resonance imaging template space for the creation of improvement maps and anatomical evaluation.ResultsMedian UPDRS-III score off medication improved from 40 at baseline to 21 on stimulation at one-year follow-up (48%, p < 0.0005). PDQ-39 summary index did not change, but the subdomain activities of daily living (ADL) and stigma improved (25%, p < 0.03 and 75%, p < 0.01), whereas communication worsened (p < 0.03). For UPDRS-III sub-items, stimulation alone reduced median tremor score by 9 points, akinesia by 3, and rigidity by 2 points at one-year follow-up in comparison to baseline (90%, 25%, and 29%, respectively, p < 0.01). Visual analysis of the anatomical improvement maps based on simulated electrical fields showed no evident relation with the degree of symptom improvement and neither did statistical analysis show any significant correlation.ConclusionsBilateral cZi-DBS alleviates motor symptoms, especially tremor, and improves ADL and stigma in PD patients one year after surgery. Improvement maps may be a useful tool for visualizing the spread of the electric field. However, there was no clear-cut relation between anatomical location of the electric field and the degree of symptom relief.  相似文献   
7.
8.
Humans use the same representations to code self-produced and observed actions. Neurophysiological evidence for this view comes from the discovery of the so-called mirror neurons in premotor cortex of the macaque monkey. These neurons respond when the monkey performs a particular action but also when it observes the same behavior in another individual. In humans, such direct links between perception and action seem to mediate action priming, where a response is facilitated when a similar action is observed. An issue that has not been fully resolved concerns the role of selective attention in these processes. Action priming appears to be an automatic process in the sense that the observed action can be irrelevant to the observer's task and nevertheless prime similar responses. However, it is not known whether attention has to be oriented to the action for these processes to be engaged. It is demonstrated here that spatial attention indeed has to be oriented to the action related body site for action priming to take place. Furthermore, if attention is oriented to the appropriate body site, there need be no visual cues to action for action priming to emerge.  相似文献   
9.
BACKGROUND: It is essential to account for acculturation in any research conducted in multicultural populations. Both unidimensional and bidimensional approaches are used to measure the extent of acculturation; however, neither one of them is optimal. OBJECTIVE: To explore the immigrants' rating of the extent of their acculturation (self-reported integration) in contrast to an external (researchers') measurement. METHODS: Fifteen in-depth interviews with strategically sampled Russian-speaking men and women aged 25-70 years, with varying marital and employment status and living permanently in Stockholm, Sweden, were analyzed using a content analysis technique. The results were validated by means of a series of additional mini-interviews by telephone. RESULTS: The immigrants' self-reported integration corresponded with the researchers' bidimensional measurement of the extent of acculturation of these immigrants. Self-reported integration accounted for the mastering of the formal criteria of integration, resolving of grief concerning the homeland, and fulfilling the internal criteria of integration. DISCUSSION: Self-reported integration may be used as a proxy for acculturation but its application should be tested primarily in other settings and in a quantitative analysis.  相似文献   
10.
Low‐density lipoprotein cholesterol (LDL‐C) levels are significantly associated with atherosclerotic cardiovascular disease (ASCVD) risk, and studies using interventions that lower LDL‐C levels have been shown to reduce the risk of ASCVD events and mortality. Statin treatment is the current first‐line therapy for lowering LDL‐C and reducing ASCVD risk. However, many patients are still unable to reach recommended LDL‐C goals on maximally tolerated statin therapy. Monoclonal antibodies that inhibit proprotein convertase subtilisin/kexin type 9, including evolocumab (previously AMG 145), dramatically lowered LDL‐C in phase 2 clinical trials when administered alone or in combination with a statin. The aim of this phase 3 study is to evaluate the efficacy of 12 weeks of subcutaneous evolocumab (vs placebo) administered every 2 weeks or every month in combination with a statin in patients with hypercholesterolemia and mixed dyslipidemia. This study will also provide comparative efficacy, safety, and tolerability data between evolocumab and ezetimibe when added to background atorvastatin therapy.  相似文献   
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