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Clinical trials are probably the most informative experiments to help an understanding of multiple sclerosis (MS) biology. Recent successes with CD20‐depleting antibodies have focused attention towards B cell subsets as important mediators in MS. The trial of tabalumab (NTC00882999), which inhibits B cell activation factor (BAFF), is reported and reviewed and this trial is contrasted with the trial on the inhibition of a proliferation‐inducing ligand (APRIL) and BAFF using atacicept (NCT00642902). Both tabalumab and atacicept induce depletion of mature B cells and inhibit antibody formation, but they fail to deplete memory B cells and do not inhibit relapsing MS. Atacicept is reported to augment memory B cell responses and may precipitate relapse, suggesting the importance of APRIL. However, BAFF inhibition can enhance peripheral blood memory B cell responses, which was not associated with augmented relapse. Although other interpretations are possible, these data further support the hypothesis that memory B cells may be of central importance in relapsing MS, as they are the major CD20+ B cell subset expressing APRIL receptors. They also suggest that quantitative and/or qualitative differences in B cell responses or other factors, such as an immune‐regulatory effect associated with APRIL, may be important in determining whether MS reactivates following neutralization of peripheral B cell maturation and survival factors.  相似文献   
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《Brain stimulation》2020,13(1):175-189
BackgroundTranscranial magnetic stimulation (TMS) enables non-invasive modulation of brain activity with both clinical and research applications, but fundamental questions remain about the neural types and elements TMS activates and how stimulation parameters affect the neural response.ObjectiveTo develop a multi-scale computational model to quantify the effect of TMS parameters on the direct response of individual neurons.MethodsWe integrated morphologically-realistic neuronal models with TMS-induced electric fields computed in a finite element model of a human head to quantify the cortical response to TMS with several combinations of pulse waveforms and current directions.ResultsTMS activated with lowest intensity intracortical axonal terminations in the superficial gyral crown and lip regions. Layer 5 pyramidal cells had the lowest thresholds, but layer 2/3 pyramidal cells and inhibitory basket cells were also activated at most intensities. Direct activation of layers 1 and 6 was unlikely. Neural activation was largely driven by the field magnitude, rather than the field component normal to the cortical surface. Varying the induced current direction caused a waveform-dependent shift in the activation site and provided a potential mechanism for experimentally observed differences in thresholds and latencies of muscle responses.ConclusionsThis biophysically-based simulation provides a novel method to elucidate mechanisms and inform parameter selection of TMS and other cortical stimulation modalities. It also serves as a foundation for more detailed network models of the response to TMS, which may include endogenous activity, synaptic connectivity, inputs from intrinsic and extrinsic axonal projections, and corticofugal axons in white matter.  相似文献   
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近10年来,甲状腺外科快速发展。随着甲状腺外科相关指南、专家共识的不断修订与完善,在专业团体的引导下,中国甲状腺外科在术前诊断、手术方式、治疗方法创新等方面实现了可喜发展,病人5年生存率明显提高。甲状腺疾病诊治技术快速革新、外科术式的发展与统一、多学科诊疗模式发展与应用、术后规范化管理助力疗效提高、重视特殊情况下的甲状腺癌及髓样癌诊治以及质量控制体系的建立与完善等综合发展提升了甲状腺癌诊疗的安全性、精准性,有效的改善了病人生活质量、延长生存时间,为建设健康中国贡献力量。  相似文献   
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摘要:目的 基于Hippo信号通路核心基因mRNA表达,探索具有补肾填精壮骨之效的金刚丸治疗去卵巢(ovariectomized,OVX)大鼠骨质疏松症的疗效机制。方法 通过OVX法建立绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)大鼠模型,分正常组、假手术组、模型组、金刚丸高剂量组、金刚丸中剂量组、金刚丸低剂量组、仙灵骨葆对照组、骨化三醇对照组。灌胃12周后,通过X射线骨密度仪检测骨密度、镜下观察股骨头显微形态结构、ELISA法检测血清ALP、实时定量RT-PCR检测骨组织Mst2、Lats1、Taz mRNA表达。结果 ①与正常组比较,模型组股骨骨密度显著降低(P<0.01)、骨微结构显著破坏、血清ALP显著降低(P<0.01)、骨组织Mst2、Lats1 mRNA表达显著升高(P<0.01)、Taz mRNA表达显著降低(P<0.01);②与模型组比较,除金刚丸低剂量组外,各给药组的骨密度均显著升高(P<0.01),各给药组骨微结构破坏均得到改善、血清ALP均显著升高(P<0.01)、骨组织Mst2、Lats1 mRNA表达均显著降低(P<0.01)、Taz mRNA表达均显著升高(P<0.01),均以金刚丸高剂量组最为显著。结论 骨组织Hippo信号通路核心基因Mst2、Lats1 mRNA表达上调,Taz mRNA表达下调可能是PMOP的发病机制之一;金刚丸可能通过下调骨组织Hippo信号通路核心基因Mst2、Lats1 mRNA表达、上调Taz mRNA表达的机制,有效防治PMOP。  相似文献   
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Central illustration: cumulative major adverse cardiac events (MACE) and bioresorbable vascular scaffold (BVS) thrombosis rates after 1, 2, 3, 4 and 5 years.
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Lifetime red cell concentrate (RCC) transfusions still account for significant iron overload‐related morbidity and mortality despite chelation therapy in thalassaemia. The cumulative risk of transfusion‐transmitted infections is substantial for thalassaemia patients. Pathogen reduction technologies for RCC may imply a proactive approach against new/re‐emerging pathogens and may be an ultimate safeguard for transfusion safety in the developing countries. Red cell alloimmunization may become a significant clinical challenge in thalassaemia. The availability of high‐throughput molecular blood group antigen typing in the donors may allow perfect match transfusion, beyond ABO‐D and CEK antigen‐matched transfusions. Allogeneic stem cell transplantation (A‐SCT) is the only available curative therapy in thalassaemia, but carries a substantial risk of serious adverse events and mortality. Gene addition therapy for correction of the α‐globin chain imbalance overcomes the problems of donor availability and immunological complications of A‐SCT. Gene editing by either gene disruption or correction emerged as a potential alternative to gene addition therapy in beta‐thalassaemia. A new era of novel therapeutics targeting α/β imbalance, ineffective erythropoiesis or iron dysregulation is unfolding in thalassaemia management, and a number of those now have agents in preclinical and clinical development. Hydroxyurea (HU) may improve globin chain imbalance and be beneficial for reducing or omitting transfusion requirement. Ruxolitinib has allowed steady decrease in spleen volume that may serve for avoiding splenectomy in beta‐thalassaemia. Luspatercept may restore normal erythroid differentiation and improve anaemia. Hepcidin mimetics or TMPRSS6 inhibitors may modulate ineffective erythropoiesis by iron restriction and improve anaemia and organ iron loading.  相似文献   
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