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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   
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In a retrospective controlled clinical study we investigated the efficacy of bromides (BR) as to the frequency of generalized tonic-clonic seizures (GTCS) as a monotherapy (n = 5) or combined with other antiepileptic drugs (AEDs) (n = 55), and compared the results statistically with those achieved with a treatment based on phenobarbitone (PB) and/or phenytoin (PHT) in a very similar group of another 60 patients. All patients treated with BR had previously proved to be pharmaco-resistant. In most of the cases the epilepsies were based on early cerebral lesions, and were partly associated with severe mental and physical handicaps. Most of the patients were between three and 14 years old. The percentage of responders was 58%, which means a reduction in the GTCS-frequency of more than 50%. The positive result was observed for 28 months on the average. 27% of all patients became free of GTCS for 18 months on the average (range, 44 days to 62 months), and 32% were improved (reduction in GTCS-frequency of more than 50% while not GTCS-free) for nearly three years on the average (range, 79 days to 110 months). Compared to PHT or PB, BR were slightly more efficient and similarly tolerable, but no statistically significant difference was seen (48% responders in the control group versus 58% responders in the BR-group). Thus, the statistical correlation with competitive therapies confirmed the good efficacy of BR against GTCS, which was previously demonstrated by clinical tests without control studies. We recommended BR in the case of every pharmaco-resistant epilepsy with GTCS as a therapeutic alternative.  相似文献   
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OBJECTIVE: Apathy is among the most frequent neuropsychiatric symptoms in dementia, particularly Alzheimer disease. The Apathy Evaluation Scale (AES) has been widely employed for assessing apathy in different patient groups. To further facilitate the usage of the AES, an abbreviated version was constructed. METHOD: On basis of a sample of 356 nursing home residents, a cross-validation procedure was carried out to develop a brief version of the AES. According to a thorough clinical examination, 85% of the residents were demented, 8% presented with mild cognitive impairment, whereas 7% did not present any cognitive deficits. After subdividing the patient group into two matched samples, the first subsample was used to identify problematic items due to defined psychometric and content-related criteria. The original 18-item scale was thus reduced to 10 items. Psychometric properties of the shortened version were subsequently reassessed in the second subsample. RESULTS: The short version demonstrated favorable psychometric properties that could be confirmed by cross-validation with the second sample. Correlations with the original full-length version were high (r = 0.97 for both subsamples); the shortened scale yielded no substantial losses regarding internal consistency or construct validity (correlations with the respective subscales of the Neuropsychiatric Inventory). CONCLUSION: The frequency of apathetic symptoms in the nursing home residents included confirms the clinical importance of apathy for understanding dementia. Given this specific patient population, setting, and mode of data collection, the short-version AES seems to be a valuable and time-efficient instrument for assessing apathy.  相似文献   
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Reducing the workload of the beta cell by inhibiting insulin secretion may provide beneficial effects for patients with type 2 diabetes. The aim of this study was to investigate the effect of NN414, a beta cell selective potassium channel opener in patients with type 2 diabetes. 24 patients were treated for seven days (placebo, 1.5, 4.5, and 10 mg/kg). In accordance with the pharmacological profile a significant and selective inhibition of insulin secretion was observed (1 h post dose). There were no statistically significant effects on overall glycaemic control. Based on OGTT derived parameters a borderline significant improvement in beta-cell function (1st and 2nd phase insulin secretion) was observed from Day 1 to Day 7.  相似文献   
18.
Noninvasive studies of cerebral metabolism were performed with use of localized proton MR spectroscopy (MRS) in both healthy controls (n = 4, age 6 weeks to 2 years) and infants (n = 4, age 3-15 months) who had impaired peroxisomal functions classified as variants of Zellweger syndrome. All patients revealed a marked decrease of N-acetylaspartate in white and gray matter, thalamus, and cerebellum, indicating impairment of normal neuronal development as well as neuronal loss. In two cases an increase of cerebral glutamine and a decrease of the cytosolic polyol myo-inositol in gray matter and striatum reflected the impact of a concomitant effect on hepatic function. Two cases 3 and 6 months of age exhibited a notable elevation of mobile lipids and/or cholesterol in white matter. These patients with severe disease died within 4 weeks after the MRS examination. While an increase of free fatty acids generally associated with a lysosomal storage disease was not consistently observed by proton MRS of brain, this technique provides a convenient and safe tool for the direct assessment of neuropathologic aspects of Zellweger syndrome such as neuronal degeneration, demyelination, and consequences of compromised liver function.  相似文献   
19.
Biological safety cabinetry.   总被引:1,自引:1,他引:1       下载免费PDF全文
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20.
The precision by which sodium balance is regulated suggests an intricate interaction between modulatory factors released from intra- and extrarenal sources. Intrarenally produced dopamine has a central role in this interactive network. Dopamine, produced in renal tubular cells acts as an autocrine and paracrine factor to inhibit the activity of Na+,K+-ATPase as well as of a number of sodium influx pathways. The natriuretic effect of dopamine is most prominent under high salt diet. The antinatriuretic effects of noradrenaline, acting on alpha-adrenoceptors and angiotensin II are opposed by dopamine as well as by atrial natriuretic peptide (ANP). Several lines of evidence have suggested that ANP acts via the renal dopamine system and recent studies from our laboratory have shown that this effect is attributed to recruitment of silent D1 receptors from the interior of the cell towards the plasma membrane. Taken together, the observations suggest that dopamine coordinates the effects of antinatriuretic and natriuretic factors and indicate that an intact renal dopamine system is of major importance for the maintenance of sodium homeostasis and normal blood pressure.  相似文献   
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