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31.
Calcitonin-related gene peptide (CGRP) plays an important role in orofacial inflammatory pain. The aim of this study was to determine whether periodontal CGRP contributes to orofacial pain induced by experimental tooth movement in rats. Male Sprague–Dawley rats were used in this study. Closed coil springs were used to deliver forces. Rats were euthanized on 0 d, 1 d, 3 d, 5 d, 7 d, and 14 d following experimental tooth movement. Then, alveolar bones were obtained for immunostaining of periodontal tissues against CGRP. Two hours prior to euthanasia on each day, orofacial pain levels were assessed through rat grimace scale. CGRP and olcegepant (CGRP receptor antagonist) were injected into periodontal tissues to verify the roles of periodontal CGRP in orofacial pain induced by experimental tooth movement. Periodontal CGRP expression levels and orofacial pain levels were elevated on 1 d, 3 d, 5 d, and 7 d following experimental tooth movement. The two indices were significantly correlated with each other and fitted into a dose–response model. Periodontal administration of CGRP could elevate periodontal CGRP expressions and exacerbate orofacial pain. Moreover, olcegepant administration could decrease periodontal CGRP expressions and alleviate orofacial pain. Therefore, periodontal CGRP plays an important role in pain transmission and modulation following experimental tooth movement. We suggest that it may participate in a positive feedback aiming to amplify orofacial pain signals.  相似文献   
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Heat stress (HS) is a notable risk factor for female reproductive performance. In particular, impaired oocyte maturation was thought to contribute largely to the HS-induced reproductive dysfunctions. In this study, we confirmed that oocytes undergoing GVBD were much susceptible to HS, and thus compromising subsequent embryonic development. Using N-acetyl-l-cysteine (NAC), we found supplementation of a relatively high dose NAC during in vitro maturation, can protect oocytes from HS-induced complications, and thus rescuing impaired embryonic development. Further analysis indicated that mechanisms responsible for protecting GVBD oocytes from HS by NAC may include: (1) reversing disorganized spindle assembly and inhibited extracellular signal–regulated kinase (ERK) signaling; (2) correcting erroneous H3K27me3 modification and dysregulated expression of imprinted genes; (3) alleviating increased intraoocyte reactive oxygen species accumulation and apoptosis initiation. Our study, focusing on the oocyte meiotic maturation, may provide a safe and promising strategy for protecting reproductive sows under environmental hyperthermal conditions.  相似文献   
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The effect of tuna eyeball oil (TEO) on lipopolysaccharide (LPS)-induced inflammation in macrophage cells was investigated. TEO had no cytotoxicity in cell viability as compared to the control in LPS induced RAW 264.7 cells. TEO reduced the levels of NO and pro-inflammatory cytokines by up to 50% in a dose-dependent manner. The expression of NF-κB and MAPKs as well as iNOS and COX-2 proteins was reduced by TEO, which suggests that its anti-inflammatory activity is related to the suppression of the NF-κB and MAPK signaling pathways. The rate of formation of ear edema was reduced compared to that in the control at the highest dose tested. In an acute toxicity test, no mice were killed by TEO doses of up to 5000 mg/kg body weight during the two week observation period. These results suggested that TEO may have a significant effect on inflammatory factors and be a potential anti-inflammatory therapeutic.  相似文献   
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目的比较骨填充网袋椎体成形术(Vesselplasty)与经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)治疗 Kümmell 病的临床疗效。方法2015 年 1 月—2018 年 12 月收治 63 例 Kümmell 病患者,其中 28 例采用 Vesselplasty 治疗(Vesselplasty 组),35 例采用 PKP 治疗(PKP 组)。两组患者性别、年龄、病程、骨密度 T 值、骨折节段及术前疼痛视觉模拟评分(VAS)、Oswestry 功能障碍指数(ODI)、伤椎前缘高度、后凸 Cobb 角等一般资料比较,差异均无统计学意义(P>0.05),具有可比性。记录两组手术时间、术中透视时间、骨水泥注射量、骨水泥渗漏率、骨水泥弥散面积率和随访期间并发症发生情况,以及术前、术后 1 d、末次随访时 VAS 评分、ODI、伤椎前缘高度、后凸 Cobb 角。 结果两组患者均获随访,随访时间 12~36 个月,平均 24.2 个月。Vesselplasty 组手术时间、术中透视时间、骨水泥注射量、骨水泥弥散面积率均明显小于 PKP 组(P<0.05)。Vesselplasty 组骨水泥渗漏率(7.14%)明显低于 PKP 组(34.29%)(χ2=5.153,P=0.023)。两组患者术后 1 d 及末次随访时 VAS 评分、ODI、伤椎前缘高度、后凸 Cobb 角均较术前显著改善(P<0.05),术后两组间比较差异均无统计学意义(P>0.05)。随访期间两组均未见术椎再塌陷,Vesselplasty 组邻椎骨折发生率(7.14%)与 PKP 组(14.29%)比较,差异无统计学意义(χ2=0.243,P=0.622)。 结论Vesselplasty 和 PKP 治疗 Kümmell 病疗效相似,均能有效缓解患者疼痛症状,改善生活质量,部分恢复伤椎高度,矫正椎体后凸。但前者具有手术时间短、术中透视时间少、骨水泥渗漏少等优势。  相似文献   
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《药学学报(英文版)》2020,10(3):414-433
The T cell co-stimulatory molecule OX40 and its cognate ligand OX40L have attracted broad research interest as a therapeutic target in T cell-mediated diseases. Accumulating preclinical evidence highlights the therapeutic efficacy of both agonist and blockade of the OX40–OX40L interaction. Despite this progress, many questions about the immuno-modulator roles of OX40 on T cell function remain unanswered. In this review we summarize the impact of the OX40–OX40L interaction on T cell subsets, including Th1, Th2, Th9, Th17, Th22, Treg, Tfh, and CD8+ T cells, to gain a comprehensive understanding of anti-OX40 mAb-based therapies. The potential therapeutic application of the OX40–OX40L interaction in autoimmunity diseases and cancer immunotherapy are further discussed; OX40–OX40L blockade may ameliorate autoantigen-specific T cell responses and reduce immune activity in autoimmunity diseases. We also explore the rationale of targeting OX40–OX40L interactions in cancer immunotherapy. Ligation of OX40 with targeted agonist anti-OX40 mAbs conveys activating signals to T cells. When combined with other therapeutic treatments, such as anti-PD-1 or anti-CTLA-4 blockade, cytokines, chemotherapy, or radiotherapy, the anti-tumor activity of agonist anti-OX40 treatment will be further enhanced. These data collectively suggest great potential for OX40-mediated therapies.  相似文献   
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目的:基于光学相干断层扫描血管成像(OCTA)技术探讨青少年儿童近视与视网膜表层微血管密度 及视网膜厚度的相关性。方法:横断面研究。共纳入2018年5─11月于四川大学华西医院眼科门 诊就诊的7~14岁青少年近视患者105例(193眼)。对所有受检者进行光学相干断层扫描(OCT)和 OCTA检查,量化分析黄斑中心凹视网膜厚度和各部位视网膜表层微血管密度。单因素方差分析比 较低、中、高度近视组各部位视网膜微血管密度及视网膜厚度的差异。采用Pearson相关系数探讨视 网膜厚度与各部位视网膜表层微血管密度的相关性。Spearman相关系数用于探讨等效球镜与中心凹、 旁中心凹视网膜表层微血管密度以及视网膜厚度的关系;分段多项式函数分析等效球镜度与外环及 直径6 mm完整视网膜表层微血管密度的关系。结果:旁中心凹、外环、直径6 mm完整区域视网膜 表层微血管密度在低、中、高度近视组间比较差异均具有统计学意义(F=11.651、14.499、14.232, 均P<0.001)。年龄与中心凹视网膜厚度之间有较弱正相关关系(r=0.187,P=0.011),与各部位微血管 密度均无相关性。等效球镜度与旁中心凹视网膜微血管密度有相关性(r=-0.301,P<0.001),与外环、 直径6 mm完整区域视网膜表层微血管密度呈曲线相关(r=-0.319,P<0.001;r=-0.307,P<0.001)。 但与中心凹视网膜表层微血管密度及视网膜厚度无显著相关性。此外,中心凹处视网膜厚度与微血 管密度呈正相关(r=0.691,P<0.001),与其余部位微血管密度无相关性。结论:青少年近视程度数 与旁中心凹、外环及直径6 mm完整区域视网膜表层微血管密度呈负相关;中心凹处视网膜厚度与年 龄、微血管密度呈正相关。  相似文献   
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