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991.
Interventions for cognitive deficits in adults with brain tumours   总被引:1,自引:0,他引:1  
Increased life expectancy in patients with brain tumours has led to a greater risk of cognitive deficits, particularly during disease-free periods. Here, we review the empirical studies that have been done to treat or to prevent cognitive impairment in patients with brain tumours. Both pharmacological interventions and cognitive rehabilitation programmes have been used. Although both types of study have reported some successes, these are often difficult to interpret owing to limitations in the methods used. Most of the studies reviewed did not use a randomised group design to control for possible confounding factors such as placebo and practice effects. Investigations of newer, targeted therapies have reported delays in cognitive deterioration, but these need to be confirmed in future studies. Neuroprotection represents another potentially promising, novel approach to prevention of cognitive impairment in this vulnerable population of patients. Finally, we describe studies in patients with cancers outside the CNS, to highlight further possibilities for the prevention and treatment of cognitive deficits.  相似文献   
992.
993.
Quality of life (QoL) in patients with schizophrenia has been assessed both from physician and patient perspectives, but little is known about agreement between these perspectives and predictors of agreement. The aim of this study was to analyze a large sample of patients with schizophrenia to discover patterns of physician and patient-rated QoL in patients with schizophrenia and identify predictors for these patterns. This study (EASE) was designed to investigate the QoL and subjective well-being in out-patients with schizophrenia during antipsychotic treatment in a naturalistic setting. Assessments were carried out at baseline and at 3, 6, 9 and 12 months, using the quality of life scale (QLS) and the subjective well-being on neuroleptics scale (SWN-K). A hierarchical cluster analysis was used to define groups of patients based on the SWN-K and QLS total scores at all visits. 1174 patients were included in the cluster analyses that were based on SWN-K and QLS total scores over time. Four distinct clusters were identified: patients with: (1) continuously high QoL (23.2%), (2) continuously moderate QoL (45.8%), (3) continuously low QoL (11.2%), and (4) improving QoL (19.9%). Clusters 1-3 were stable in terms of QoL, whilst cluster 4 changed towards improvement. Various predictors for the four clusters were identified. In the cluster with improving QoL, the absence of treatment with an oral conventional antipsychotic pre-study and no medication change due to lack of efficacy at baseline were predictors for improvement. In the cluster with continuously high QoL, no medication change due to lack of efficacy and lowest CGI-S scores at baseline were predictors. Oral conventional antipsychotic treatment pre-study was predictive for the cluster with continuously moderate QoL. In the cluster with continuously low QoL, medication change due to lack of efficacy and highest CGI-S scores were predictors. These findings suggest that various factors may predict whether a patient with schizophrenia experiences a continuously high QoL, a continuously moderate QoL, a continuously low QoL, or improving QoL whilst on antipsychotic treatment.  相似文献   
994.
In 176 patients with Guillain-Barré syndrome the subclass and cross-reactivity of serum IgG antibodies to motor gangliosides was related to preceding infections and clinical phenotypes. Two subgroups of patients were identified. Presence of only IgG1 antibodies was related to diarrhea, positive Campylobacter serology, cross-reactive antibodies to C. jejuni lipo-oligosaccharides and poor outcome. In contrast, having both IgG1 and IgG3 antibodies was related to upper respiratory tract infections, cross-reactive antibodies to Haemophilus influenzae lipo-oligosaccharides and better outcome. These findings support a model in which C. jejuni and H. influenzae infections induce two distinct patterns of cross-reactive antibodies with different clinical outcome.  相似文献   
995.
BACKGROUND AND AIMS: A mailed survey to our readership expressed an interest in providing journal CME. In January 2006, following an assessment of the readership's educational needs and the development of educational objectives to span a 12-month program, two articles per issue were provided to participants to gain category 1 credit free of charge. METHODS: Participants completed a mandatory electronic evaluation after each CME activity that they had completed. These prospective data were collected to determine participant demographics, satisfaction, and outcome results. RESULTS: A total of 1,329 CME credits were provided during the 2006 volume year. Ninety-one percent of these participants were in private practice, 98% of the participants indicated a good to excellent overall satisfaction with the CME activity, 97% indicated their experience was good to excellent compared to other journals that they had participated for CME credit, and 97% of the participants indicated that they thought the CME activity increased their knowledge and/or skills related to patient care. CONCLUSION: The results of our 1-yr outcome analysis indicate that there is a need for continued journal-based CME and that our participants are very satisfied with the process. This CME activity format also appears to have improved the participants' knowledge and their delivery of patient care.  相似文献   
996.
This exploratory follow-up study investigated whether EEG parameters can predict future cognitive performance. Forty elderly subjects, ranging from cognitively unimpaired to those with Alzheimer disease underwent EEG registration at baseline and neuropsychological examination at both baseline and follow-up. We assessed relations between EEG measures and future cognitive performance (i.e., global cognition, memory, language, and executive functioning) controlling for age, follow-up time, and baseline cognitive performance. Regression models were constructed to predict performance on the Cambridge Cognitive Examination, a widely used tool within dementia screenings. Baseline EEG measures, i.e., increased theta activity (4-8 Hz) during eyes closed and less alpha reactivity (8-13 Hz) during eyes open and memory activation, indicated lower global cognitive, language (trend significant), and executive performance at follow-up. A regression model combining baseline cognitive and EEG measures provided the best prediction of future Cambridge Cognitive Examination performance (93%). EEG and cognitive measures alone predicted, respectively, 43% and 92% of variance. EEG and cognitive measures combined provided the best prediction of future cognitive performance. Although the "cognition only" model showed similar predictive power, the EEG provided significant additional value. The added value of EEG registration in the diagnostic work-up of dementia should be further assessed in larger samples.  相似文献   
997.
Cellular origin and environmental cues regulate stem cell fate determination. Neuroepithelial stem cells form the central nervous system (CNS), whereas neural crest stem cells generate the peripheral (PNS) and enteric nervous system (ENS). CNS neural stem/progenitor cell (NSPC) fate determination was investigated in combination with dissociated cultures or conditioned media from CNS, PNS, or ENS. Cells or media from ENS or PNS cultures efficiently promoted NSPC differentiation into neurons, glia, and smooth muscle cells with a similar morphology as the feeder culture. Together with CNS cells or its conditioned medium, NSPC differentiation was partly inhibited and cells remained immature. Here, we demonstrate that secreted factors from the environment can influence CNS progenitor cells to choose a PNS-like cell fate.  相似文献   
998.

Background

Little is known about the social context of girls with conduct disorder (CD), a question of increasing importance to clinicians and researchers. The purpose of this study was to examine the associations between three social context domains (neighborhood, family characteristics, and parenting behaviors) and CD in adolescent girls, additionally testing for race moderation effects. We predicted that disadvantaged neighborhoods, family characteristics such as parental marital status, and parenting behaviors such as negative discipline would characterize girls with CD. We also hypothesized that parenting behaviors would mediate the associations between neighborhood and family characteristics and CD.

Methods

We recruited 93 15–17 year-old girls from the community and used a structured psychiatric interview to assign participants to a CD group (n = 52) or a demographically matched group with no psychiatric disorder (n = 41). Each girl and parent also filled out questionnaires about neighborhood, family characteristics, and parenting behaviors.

Results

Neighborhood quality was not associated with CD in girls. Some family characteristics (parental antisociality) and parenting behaviors (levels of family activities and negative discipline) were characteristic of girls with CD, but notll. There was no moderation by race. Our hypothesis that the association between family characteristics and CD would be mediated by parenting behaviors was not supported.

Conclusion

This study expanded upon previous research by investigating multiple social context domains in girls with CD and by selecting a comparison group who were not different in age, social class, or race. When these factors are thus controlled, CD in adolescent girls is not significantly associated with neighborhood, but is associated with some family characteristics and some types of parental behaviors. However, the mechanisms underlying these relationships need to be further investigated. We discuss possible explanations for our findings and suggest directions for future research.  相似文献   
999.
1000.
OBJECTIVE—Activation of the receptor for advanced glycation end products (RAGE) in diabetic vasculature is considered to be a key mediator of atherogenesis. This study examines the effects of deletion of RAGE on the development of atherosclerosis in the diabetic apoE−/− model of accelerated atherosclerosis.RESEARCH DESIGN AND METHODS—ApoE−/− and RAGE−/−/apoE−/− double knockout mice were rendered diabetic with streptozotocin and followed for 20 weeks, at which time plaque accumulation was assessed by en face analysis.RESULTS—Although diabetic apoE−/− mice showed increased plaque accumulation (14.9 ± 1.7%), diabetic RAGE−/−/apoE−/− mice had significantly reduced atherosclerotic plaque area (4.9 ± 0.4%) to levels not significantly different from control apoE−/− mice (4.3 ± 0.4%). These beneficial effects on the vasculature were associated with attenuation of leukocyte recruitment; decreased expression of proinflammatory mediators, including the nuclear factor-κB subunit p65, VCAM-1, and MCP-1; and reduced oxidative stress, as reflected by staining for nitrotyrosine and reduced expression of various NADPH oxidase subunits, gp91phox, p47phox, and rac-1. Both RAGE and RAGE ligands, including S100A8/A9, high mobility group box 1 (HMGB1), and the advanced glycation end product (AGE) carboxymethyllysine were increased in plaques from diabetic apoE−/− mice. Furthermore, the accumulation of AGEs and other ligands to RAGE was reduced in diabetic RAGE−/−/apoE−/− mice.CONCLUSIONS—This study provides evidence for RAGE playing a central role in the development of accelerated atherosclerosis associated with diabetes. These findings emphasize the potential utility of strategies targeting RAGE activation in the prevention and treatment of diabetic macrovascular complications.The receptor for advanced glycation end products (RAGE) is a multiligand cell surface molecule belonging to the immunoglobulin superfamily (1). It is expressed as full-length, N-truncated, and C-truncated isoforms, generated in humans by alternative splicing (2). Activation of the full-length RAGE receptor has been implicated in a range of chronic diseases, including various diabetic complications and atherosclerosis (1). In particular, studies in RAGE−/− mice that carry the dominant-negative form of the receptor (26) and in RAGE-overexpressing mice (7) have confirmed an important role of RAGE activation in the development of diabetic nephropathy, neuropathy, and impaired angiogenesis. RAGE activation has also been implicated in the acceleration of atherosclerotic lesion formation as well as in the maintenance of proinflammatory and prothrombotic mechanisms, characteristic of diabetes-accelerated atherosclerosis (8,9). RAGE also represents an important mediator of oxidative stress in diabetes. Activation of RAGE in vitro leads to increased NADPH oxidase expression, mitochondrial oxidase activity, and downregulation of endogenous antioxidant activity (10,11). RAGE−/− mice have a suppression of neointimal proliferation after externally induced arterial injury in the absence of diabetes (12). Moreover, blockade of RAGE-dependent signaling by soluble RAGE (sRAGE) has been shown to inhibit the progression of atherosclerotic changes (8,9) and kidney disease (3) in diabetic mice, possibly by suppressing the activation of nuclear factor-κB (NF-κB) activation and inflammatory cytokine expression. The present study examined the role of RAGE in the development of diabetes-accelerated atherosclerosis in a model of insulin deficiency, the streptozotocin-induced diabetic RAGE−/−/apoE−/− mouse. Our aim was to determine the effect of global RAGE deficiency, which includes absence of both the full-length receptor and endogenous sRAGE on the development of vascular lesions in the presence and absence of diabetes. Furthermore, key mediators of the atherosclerotic process in diabetes were examined, and the effects on these pathways were assessed in these RAGE-deficient mice.  相似文献   
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