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101.
《Immunopharmacology and immunotoxicology》2013,35(4):656-662
Although researchers have recently begun to pay more attention to the immunological characteristics of microvascular endothelial cells (MVECs), there are no reports on whether activation of MVECs by interferon-γ (IFN-γ) exerts any influence on the expressions of IFN-α/β. In the present study, we examined the influence of IFN-γ on the expressions of IFN-α/β in rat intestinal mucous MVECs (RIMMVECs). Different concentrations of IFN-γ were used to stimulate cultured RIMMVECs in vitro, and the cells and cell supernatants were collected at different time intervals. The influence of IFN-γ on the expressions of IFN-α/β in the RIMMVECs was examined at the mRNA and protein levels by real-time quantitative PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The results indicated that IFN-γ was able to activate RIMMVECs, thereby leading to upregulated expressions of IFN-α/β. The real-time quantitative PCR analyses indicated that the IFN-α/β mRNA expression levels in RIMMVECs achieved their peak values after stimulation with IFN-γ at 20?ng/mL for 6?h and were increased by 14.88- and 3.82-fold, respectively, when compared with the levels in negative control cells. The ELISA analyses revealed that the IFN-α/β protein expression levels achieved their peak values after stimulation with IFN-γ at 40?ng/mL. The expression of IFN-α protein achieved its peak value at 12?h, while the expression of IFN-β protein achieved its peak value after 6?h. The present results suggest that the expression and secretion of IFNs may participate in the immunologic barrier function of MVECs. 相似文献
102.
Mioko Mori Tomohiro Kumada Kenji Inoue Fumihito Nozaki Katsuyuki Matsui Yoshihiro Maruo Mamiko Yamada Hisato Suzuki Kenjiro Kosaki Minoru Shibata 《Brain & development》2021,43(6):724-728
BackgroundThe MEHMO (mental retardation, epileptic seizures, hypogonadism and hypogenitalism, microcephaly, and obesity) syndrome, which is caused by a hemizygous variant in the EIF2S3 gene on chromosome Xp22, is associated with significant morbidity and mortality. Refractory epileptic seizures and glucose dysregulation are characteristic manifestations of the MEHMO syndrome, which can often diminish patients’ quality of life.CaseA 5-year-old boy was referred to our hospital because of profound intellectual disability, micropenis, cryptorchidism, central hypothyroidism, and microcephaly. He had neonatal hypoglycemia at birth and later experienced refractory epileptic seizures and developed obesity and insulin-dependent diabetes. A diagnosis of MEHMO syndrome was established on the basis of the patient’s clinical manifestations and de novo novel missense variant in the EIF2S3 gene (NM_001415.3:c.805 T > G) that was detected through whole-exome analysis. Although the patient’s refractory seizures and diabetes had been well controlled with a combination of ketogenic diet (KD) therapy and insulin therapy, acute fatal necrotizing pancreatitis occurred at the age of 68 months. Moreover, despite intensive care, his condition rapidly deteriorated to multiple organ failure and acute respiratory distress syndrome, resulting in death.ConclusionThe pathophysiology of glucose intolerance in MEHMO syndrome remains to be elucidated; however, recent studies have suggested that EIF2S3 gene variants could lead to glucose dysregulation and β-cell damage in the pancreas. We suspect that in the present case, KD therapy led to an abnormal load on the beta cells that were damaged owing to eIF2γ dysfunction. Therefore, the adverse effects of KD in patients with MEHMO syndrome should be considered. 相似文献
103.
Effective immune strategies for eradication of human malignancies will require a thorough understanding of the interactions of cancer with the immune system. It will be crucial to understand how to optimize and sustain a T cell immune response. Recently, our understanding of the molecular interaction that occurs between an APC and a T cell during cognate interaction has increased dramatically. In this review, various costimulatory and inhibitory molecules of the B7 and TNF families will be discussed. The emphasis will be on how these costimulatory molecules impact T cell activation and on how they can be potentially used for the treatment of cancer. costimulation cancer T cell activation 相似文献
104.
通过对束流匹配的加速器进行计划设计,比较计划参数,验证交叉执行的差异及通过率,验证束流匹配的可行性及可靠性。选取头颈、胸部和腹盆部共15例病例,分别设计Clinac iX和Trilogy两个不同治疗机的三维适形计划(3D-CRT);另选头颈、胸部和腹盆部共15例病例,分别设计两个不同治疗机的调强计划(IMRT)。比较相同计划类型不同治疗机的计划差异,评价指标包括靶区PTV的D98%、D2%、Dmax,晶体Dmax、脑干Dmax、左右肺V5 Gy、双肺V20 Gy、脊髓Dmax、膀胱D50%、小肠D2 cc、股骨头V40 Gy等危及器官及治疗机跳数MU。并对治疗机执行计划进行点剂量和面剂量验证。PTV的D98%、D2%、Dmax剂量差异最大平均值标准差分别为-0.52%±0.30%、0.53%±0.45%、-0.55%±0.17%,危及器官剂量差异最大平均值为膀胱D50%(0.94%±0.84%);Clinac iX和Trilogy治疗机执行所有计划的最大绝对剂量偏差分别为2.36%和-2.80%。MatriXX和PV的γ验证通过率结果平均值分别在97.00%和96.00%以上,Clinac iX最小值为95.40%,Trilogy最小值为95.90%。两台经过束流匹配的治疗机之间交换执行计划的剂量学偏差在临床可接受的范围内,各项参数能精准执行,必要时可以在两台治疗机之间交换执行计划,保证病人放疗疗程完整。 相似文献
105.
Yan Li Yuan-Yi Zhang Li-Teng Yang Jiang-Qi Liu Chuan Zhou Zhi-Qiang Liu Gui Yang Li-Hua Mo Zhi-Gang Liu Bai-Sui Feng Ping-Chang Yang 《European journal of immunology》2021,51(2):459-470
Ulcerative colitis (UC) is a disease that frequently relapses and affects more than 0.1% general population; the underlying mechanism is poorly understood. Published data show that polymorphonuclear neutrophils (PMN) contribute to the pathogenesis of UC. This study aims to identify antigen (Ag)-specific PMNs and investigate their role in UC relapse. In this study, the correlation between PMN activities and UC relapse was assessed in a group of UC patients. A UC mouse model was developed to expand the findings of UC patient study. The results showed that a positive correlation was detected between the high PMN activities and the food Ag-specific IgG amounts in colon biopsies of UC patients. UC patient-derived Ag-specific PMNs could be activated upon exposure to food specific Ag. The Ag/FcγRI complexes were detected on the surface of PMNs in UC patients. Re-exposure of sensitized PMNs to specific Ag triggered PMN activation and induced UC-like inflammation in the mouse colon. We conclude that FcγRI plays a critical role in UC relapse. Inhibition of FcγRI can efficiently inhibits experimental UC. 相似文献
106.
107.
Surang Chomphoo Hiroyuki Sakagami Hisatake Kondo Wiphawi Hipkaeo 《Journal of anatomy》2021,239(5):1196-1206
Based on a previous study by others reporting that PIP5Kγ (phosphatidylinositol 4-phosphate 5-kinase γ) and its product, phosphatidylinositol 4,5 bisphosphate (PIP2), are involved in the regulation of nociception, the present immunohistochemical study examined the localization of PIP5Kγ-immunoreactivity in dorsal root ganglia (DRG) and their peripheral and central terminal fields. PIP5Kγ-immunoreactivity was localized for the first time in the muscle spindles, in which it was found in I-bands of polar regions of intrafusal muscle fibers and also in sensory nerve terminals abutting on equatorial regions of the muscle fibers. This finding indicates the involvement of PIP5Kγ in the proprioception and suggests somehow complicated mechanisms of its involvement because of its heterogeneous localization in intra-I-band structures. In DRG, on the other hand, PIP5Kγ-immunoreactivity was shown to be localized heterogeneously, but not evenly, over apposed plasma membranes of both neurons and ganglionic satellite cells in immune electron microscopy. In addition, no peripheral nerve terminals of DRG showing its distinct immunoreactivity were found in most peripheral fields of nociception and any other sensory perception except for the proprioception through muscle spindles. In contrast, numerous central terminals of DRG in the spinal posterior horn were immunoreactive for it. This finding leads us to consider the possibility that the regulation by PIP5Kγ of nociception is dominantly exerted in DRG and sensory neural tracts central, rather than peripheral, to DRG. 相似文献
108.
109.
《Brain stimulation》2021,14(1):154-160
BackgroundTranscranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) hypothetically modulates cognitive functions by facilitating or inhibiting neuronal activities chiefly in the cerebral cortex. The effect of tDCS in the deeper brain region, the basal ganglia-cortical circuit, remains unknown.ObjectiveTo investigate the interaction between γ-aminobutyric acid (GABA) concentrations and dopamine release following tDCS.MethodThis study used a randomized, placebo-controlled, double-blind, crossover design. Seventeen healthy male subjects underwent active and sham tDCS (13 min twice at an interval of 20 min) with the anode placed at the left DLPFC and the cathode at the right DLPFC, followed by examinations with [11C]-raclopride positron emission topography (PET) and GABA-magnetic resonance spectroscopy (MRS). MRS voxels were set in the left DLPFC and bilateral striata. Paired t-tests and regression analyses were performed for PET and MRS parameters.ResultsMRS data analyses showed elevations in GABA in the left striatum along with moderate reductions in the right striatum and the left DLPFC after active tDCS. PET data analyses showed that reductions in [11C]-raclopride binding potentials (increase in dopamine release) in the right striatum were inversely correlated with those in the left striatum after active tDCS. GABA reductions in the left DLPFC positively correlated with elevations in GABA in the left striatum and with increases in right striatal dopamine release and negatively correlated with increases in left striatal dopamine release.ConclusionThe present results suggest that tDCS to the DLPFC modulates dopamine-GABA functions in the basal ganglia-cortical circuit. 相似文献
110.
《Seminars in immunology》2013,25(4):263-272
Th17 cells are a subset of CD4+ effector T cells characterized by expression of the IL-17-family cytokines, IL-17A and IL-17F. Since their discovery nearly a decade ago, Th17 cells have been implicated in the regulation of dozens of immune-mediated inflammatory diseases and cancer. However, attempts to clarify the development and function of Th17 cells in human health and disease have generated as many questions as answers. On one hand, cytokine expression in Th17 cells appears to be remarkably dynamic and is subject to extensive regulation (both positive and negative) in tissue microenvironments. On the other hand, accumulating evidence suggests that the human Th17 subset is a heterogeneous population composed of several distinct pro- and anti-inflammatory subsets. Clearly, Th17 cells as originally conceived no longer neatly fit the long-standing paradigm of stable and irrepressible effector T cell function. Here we review current concepts surrounding human Th17 cells, with an emphasis on their plasticity, heterogeneity, and their many, tissue-specific functions. In spite of the challenges ahead, a comprehensive understanding of Th17 cells and their relationship to human disease is key to ongoing efforts to develop safer and more selective anti-inflammatory medicines. 相似文献