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Functional mapping of GABA(B)-receptor subtypes in the thalamus   总被引:1,自引:0,他引:1  
The thalamus plays an important role in attention mechanisms and the generation of brain rhythms. gamma-Aminobutyric acid type B (GABA(B)) receptors are known to regulate the main output neurons of the thalamus, the thalamocortical relay (TCR) cells. However, the contributions of the two predominant GABA(B)-receptor subtypes, GABA(B(1a,2)) and GABA(B(1b,2)), to the control of TCR cell activity are unknown. Here, we used genetic and electrophysiological methods to investigate subtype-specific GABA(B) effects at the inputs to TCR cells. We found that mainly GABA(B(1a,2)) receptors inhibit the release of glutamate from corticothalamic fibers impinging onto TCR cells. In contrast, both GABA(B(1a,2)) and GABA(B(1b,2)) receptors efficiently inhibit the release of GABA from thalamic reticular nucleus (TRN) neurons onto TCR neurons. Likewise, both GABA(B(1a,2)) and GABA(B(1b,2)) receptors efficiently activate somatodendritic K(+) currents in TCR cells. In summary, our data show that GABA(B(1b,2)) receptors cannot compensate for the absence of GABA(B(1a,2)) receptors at glutamatergic inputs to TCR cells. This shows that the predominant association of GABA(B(1a,2)) receptors with glutamatergic terminals is a feature that is preserved at several brain synapses. Furthermore, our data indicate that the cognitive deficits observed with mice lacking GABA(B(1a,2)) receptors could to some extent relate to attention deficits caused by disinhibited release of glutamate onto TCR neurons.  相似文献   
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Hepatic insulin resistance is associated with hepatic steatosis and is thought to play an important role in the pathogenesis of steatohepatitis. Using a murine model of steatohepatitis (mice fed a diet deficient in methionine and choline-MCD diet), we tested the effects of the insulin-sensitising, PPARgamma agonist drug pioglitazone (PGZ) on systemic and intrahepatic insulin sensitivity and on liver pathology. Compared to controls, mice fed the MCD diet develop a significant steatohepatitis, have enhanced glucose tolerance and enhanced systemic response to insulin. PGZ did not affect the systemic insulin sensitivity in control or MCD-fed mice as assessed in vivo by intraperitoneal glucose or insulin dynamic tests. However, PGZ prevented hepatic fat accumulation and steatohepatitis induced by the MCD diet. This effect was associated with an increased mass of adipose tissue and increased expression and release of adiponectin, while hepatic acyl co-enzyme A oxidase and acyl-co-enzyme A carboxylase, regulating hepatic beta-oxidation of fatty acid, remained unchanged. Steatohepatitis in MCD-diet-fed mice was associated with intrahepatic insulin resistance as shown by a reduced phosphorylation of hepatic insulin receptor, and Akt in response to an insulin stimulus. PGZ to MCD-fed mice restored the activation of the insulin receptor and of the Akt pathway in response to insulin. In conclusion, PGZ alleviates steatosis and steatohepatitis induced by the MCD diet, an effect associated with correction of intrahepatic insulin resistance.  相似文献   
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Type I IFN are cytokines which play a central role in host resistance to viral or microbial infections and are important components linking innate and adaptive immunity. We and others have previously demonstrated that the production of IFN-beta by DC following bacterial infections or TLR triggering influences, in an autocrine manner, their maturation. In this study, we investigated whether IFN-beta release modulates the phenotype of the immature DC and their response to a subsequent TLR stimulation. The induction of CD86, HLA-DR, CD38 and B7H1 and the absence of CCR7 and CD83 expression upon IFN-beta treatment suggest that IFN-beta-primed DC remain at the site of infection acquiring an activated phenotype. These results prompted us to investigate the response of IFN-beta-primed DC to TLR stimulation. While IFN-beta pretreatment increases slightly the expression of maturation markers in TLR2- or TLR4-stimulated DC, it is able to modulate selectively the secretion of inflammatory and immuno-regulating cytokines. Interestingly, IL-27p28 subunit was induced by IFN-beta alone or during LPS-induced maturation of DC in a type I IFN-dependent manner through IFN regulatory factor-1 (IRF-1) activation. Taken together, our results shed light on the capacity of IFN-beta to finely tune DC response to invading pathogens.  相似文献   
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Robertson VJ 《Physical therapy》2007,87(8):1036-7; author reply 1038
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108.
OBJECTIVE: To compare the short-term outcomes of active individual therapy (AIT) with those of a functional restoration program (FRP). DESIGN: Prospective randomized controlled study. SETTING: Two rehabilitation centers and private ambulatory physiotherapy facilities. PARTICIPANTS: One hundred thirty-two adults with chronic low back pain. Fifty-one percent of patients on sick leave or out of work (mean duration, 180d in the 2y before treatment). INTERVENTIONS: For 5 weeks, FRP (at 25h/wk) or AIT (at 3h/wk). MAIN OUTCOME MEASURES: Trunk flexibility, back flexor, and extensor endurance (Ito and Sorensen tests), general endurance, pain intensity, Dallas Pain Questionnaire (DPQ) scores, daily activities, anxiety depression, social interest, and work and leisure activities, and self-reported improvement (work ability, resumption of sport and leisure activities). RESULTS: All outcome measures improved after treatment except endurance in AIT. There was no between-group difference for pain intensity or DPQ daily activities or work and leisure activities scores. Better results were observed in FRP for all other outcome measures. There was a significant effect of treatment and the initial value for the gain of the Sorensen score with a treatment or initial value interaction; a significant effect of treatment and initial value on the gains of Ito, endurance, and DPQ social interest and anxiety depression scores, with no treatment or initial value interaction; and a significant effect of initial value but not treatment for the gains of DPQ daily activities and work and leisure activities scores. CONCLUSIONS: Low-cost ambulatory AIT is effective. The main advantage of FRP is improved endurance. We speculate that this may be linked to better self-reported work ability and more frequent resumption of sports and leisure activities.  相似文献   
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Background Biological drugs for moderate-to-severe ulcerative colitis have changed the therapeutic perspective, while small-molecule inhibitors and new promising drugs suggest new options. Aim Assess comparative efficacy and safety of biological and new small oral drugs: commercialized and under-investigation ones for patients naïve to biological drugs. Methods A systematic review was conducted to identify the randomized clinical trials phase 2 or 3, in adults with moderate-to-severe ulcerative colitis treated with biological drugs (infliximab, adalimumab, golimumab, vedolizumab and etrolizumab) or new oral small molecules (tofacitinib and ozanimod) as first line. A Bayesian network metaanalysis was performed to inform comparative efficacy and safety of different treatments. Efficacy outcomes were clinical remission, clinical response and mucosal healing for induction therapy and clinical remission, mucosal healing and sustained clinical remission for maintenance therapy. Safety was assessed with serious adverse events and rates of infections. Results 14 references were included for network meta-analysis. For induction therapy, infliximab was the best drug for induction of clinical response and remission, while ozanimod showed to be the best for induction of mucosal healing. Tofacitinib had the highest rate of maintaining clinical remission. All treatments were similar for serious adverse events, and vedolizumab and tofacitinib had the highest rates of infections. Conclusion This network meta-analysis suggests infliximab may be the best therapeutic option for moderate-to-severe ulcerative colitis. Vedolizumab seems to have better outcomes in maintenance than in induction therapy and it appears superior to golimumab and adalimumab. Tofacitinib, ozanimod and etrolizumab show encouraging results.  相似文献   
110.
The incidence of glioblastoma (GBM) has increased in patients aged 70 years or older, and will continue to grow. Elderly GBM patients have been excluded from most clinical trials; furthermore, optimal care management as well as benefit/risk ratio of GBM treatments are still being debated. This study describes oncological patterns of care, prognostic factors, and survival for patients ≥70 years in France. We identified patients over 70 with newly diagnosed and histologically confirmed GBM on data previously published by the French Brain Tumor DataBase. We included 265 patients. Neurological deficits and mental status disorders were the most frequent symptoms. The surgery consisted of resection (RS n?=?95) or biopsy (B n?=?170); 98 patients did not have subsequent oncological treatment. After surgery, first-line treatment consisted of radiotherapy (RT n?=?76), chemotherapy (CT n?=?52), and concomitant radiochemotherapy (CRC n?=?39). The median age at diagnosis was 76, 74, and 73 years, respectively, for the untreated, B?+?RT and/or CT, RS?±?RT and/or CT groups. Median survival (in days, 95 % CI) with these main strategies, when analyzed according to surgical groups, was: B-CT n?=?41, 199[155–280]; B-CRC n?=?21, 318[166–480]; B-RT n?=?37, 149[130–214]; RS-CT n?=?11, 245[211–na]; RS-CRC n?=?18, 372[349–593]; RS-RT n?=?39, 269[218–343]. This population study for elderly GBM patients is one of the most important in Europe, and could be considered as a historical cohort to compare future treatments. Moreover, we can hypothesize that elderly patients (versus patients <70 years) are undertreated. Karnofsky performance status seems to be the most relevant clinical predictive factor, and RS and CRC have a positive impact on survival for elderly GBM patients in the general population, at least when feasible.  相似文献   
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