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31.
CD4+ CD25+ Foxp3+ regulatory T (Treg) cells play an important role in maintaining immune homeostasis. Interleukin‐10 (IL‐10), a cytokine with anti‐inflammatory capacities, also has a critical role in controlling immune responses. In addition, it is well known that production of IL‐10 is one of the suppression mechanisms of Treg cells. However, the action of IL‐10 on Treg cells themselves remains insufficiently understood. In this study, by using a Schistosoma japonicum‐infected murine model, we show that the elevated IL‐10 contributed to Treg cell induction but impaired their immunosuppressive function. Our investigations further suggest that this may relate to the up‐regulation of serum transforming growth factor (TGF‐β) level but the decrease in membrane‐bound TGF‐β of Treg cells by IL‐10 during S. japonicum infection. In addition, similar IL‐10‐mediated regulation on Treg cells was also confirmed in the murine model of asthma. In general, our findings identify a previously unrecognized opposing regulation of IL‐10 on Treg cells and provide a deep insight into the precise regulation in immune responses.  相似文献   
32.
Recently, 3 rare coding variants significantly associated with Alzheimer's disease (AD) risk have been identified in western populations using whole exome sequencing method, including p.R47H in TREM2, p.V232M in PLD3, and p.T835M in UNC5C. To examine whether these variants are genetic risk factors in patients with AD from mainland China, we sequenced exon 2 of TREM2, exon 9 of PLD3, and exon 15 of UNC5C in Chinese Han population including 360 patients with AD and 400 control individuals. As a result, none of these 3 variants were identified in all subjects, however, 1 novel variant (p.A130V) in TREM2 and 4 novel variants (p.Q860H, p.T837K, p.S843G, and p.V836V) in UNC5C were detected in unrelated patients with late-onset AD. These findings suggest the 3 rare coding variants might not play an important role in AD risk in mainland China.  相似文献   
33.
ObjectivesTransoral laser microsurgery (TLM) has gradually gained approval in the treatment of early glottic cancer. However, the oncological outcomes of TLM for glottic cancer with anterior commissure (AC) involvement are still a controversial topic. We aimed to systematically review the literature on glottic cancer (Tis-T2) with patients who received TLM as first choice therapy and to evaluate several prognostic outcomes in patients with or without AC involvement.MethodsA systematic literature retrieval was conducted in PubMed, Medline (Ovid) and Web of Science. Risk ratio (RR) between AC involvement (AC+) or without AC involvement (AC?) was assessed and 95% confidence interval(95%CI) was calculated, which was performed on RevMan 5.3.ResultsA total of 20 literatures were included when comparing the local recurrence (LR) rate of patients with or without AC involvement, and the results suggested LR matters in group AC+ over group AC? (RR = 2.39, 95%CI = 1.99–2.86, p < 0.00001). The 5-year overall survival(5yOS) rate included 10 studies, and there was no significant difference between AC+ and AC? (RR = 0.98, 95%CI = 0.93–1.02, p = 0.35). The laryngeal preservation rate (LPR) of AC+ was lower than that of AC? (RR = 0.97, 95%CI = 0.94–1.00, p = 0.04).ConclusionThe results indicate that the prognosis of early glottic cancer with AC involvement is more likely to have higher local recurrence and lower LPR but no statistical difference in 5yOS rate.  相似文献   
34.
目的:探讨优化密码对人乳头瘤病毒6b型(HPV 6b)基因表达及免疫原性的影响,为治疗性DNA疫苗的研究奠定基础。方法:设计合成含优化密码及pRB结合位点突变的HPV 6bE7(humE7)全长基因。测序验证无误后,定向克隆于pcDNA3的Kpn I和EcoR I位点,成功构建真核表达质粒pcDNA3-hu-mE7。体外转染COS-1细胞,免疫荧光检测其E7蛋白表达。C57BL/6小鼠胫前肌内接种裸DNA,观察其诱导的细胞免疫反应。结果:pcDNA3-hu-mE7在COS-1细胞获得明显表达,表达产物主要位于细胞核中。DNA免疫结果显示,与含有野生型E7基因的表达质粒pcDNA3-wtE7比较,pcDNA3-hu-mE7免疫小鼠脾细胞培养上清中IFN-γ产生明显升高,CD8^ 和CD4^ 淋巴细胞活性增强。结论:优化密码能促进HPV 6b E7蛋白表达及DNA疫苗诱导的细胞免疫反应。  相似文献   
35.
目的:利用蒙特卡罗模拟探究空气间隙对点扫描质子治疗的剂量影响。方法:利用通用蒙特卡罗程序Geant4平台构建使用射程移位器的治疗头末端的点扫描质子束流模型,并进行验证。模拟计算不同能量、不同射程移位器、不同束斑尺寸、不同束斑数目在不同空气间隙条件下的质子束流在水模体中的剂量沉积,并通过获得的积分深度剂量生成剂量修正因子对剂量的差异进行比较。结果:不同空气间隙会造成剂量损失,随空气间隙增大而增大,随水模体中深度增加而减小。对于能量更高的射束和使用水等效厚度更薄的射程移位器,剂量损失越大。束斑尺寸改变和束斑数目增加较少时造成的剂量损失与同条件下单一束流无显著差别。结论:当使用射程移位器、肿瘤位置较浅、空气间隙较大时,建议建立剂量修正因子数据库应用于治疗计划系统对剂量进行修正。  相似文献   
36.
Microvascular endothelial cell (EC) injury and the subsequent blood‐brain barrier (BBB) breakdown are frequently seen in many neurological disorders, including stroke. We have previously documented that peroxisome proliferator‐activated receptor gamma (PPARγ)‐mediated cerebral protection during ischemic insults needs Krüppel‐like factor 11 (KLF11) as a critical coactivator. However, the role of endothelial KLF11 in cerebrovascular function and stroke outcome is unclear. This study is aimed at investigating the regulatory role of endothelial KLF11 in BBB preservation and neurovascular protection after ischemic stroke. EC‐targeted overexpression of KLF11 significantly mitigated BBB leakage in ischemic brains, evidenced by significantly reduced extravasation of BBB tracers and infiltration of peripheral immune cells, and less brain water content. Endothelial cell‐selective KLF11 transgenic (EC‐KLF11 Tg) mice also exhibited smaller brain infarct and improved neurological function in response to ischemic insults. Furthermore, EC‐targeted transgenic overexpression of KLF11 preserved cerebral tight junction (TJ) levels and attenuated the expression of pro‐inflammatory factors in mice after ischemic stroke. Mechanistically, we demonstrated that KLF11 directly binds to the promoter of major endothelial TJ proteins including occludin and ZO‐1 to promote their activities. Our data indicate that KLF11 functions at the EC level to preserve BBB structural and functional integrity, and therefore, confers brain protection in ischemic stroke. KLF11 may be a novel therapeutic target for the treatment of ischemic stroke and other neurological conditions involving BBB breakdown and neuroinflammation.  相似文献   
37.
目的探讨经皮Herbert螺钉内固定治疗新鲜腕舟骨骨折的临床疗效。方法对本院2004年1月~2010年10月期间采用Herbert螺钉内固定治疗的18例新鲜腕舟骨骨折病例进行回顾性分析。骨折根据Herbert分型A2型10例,B2型6例,B3型2例。结果所有病人均获随访,随访时间为5~18个月,平均8个月,骨折均获骨性愈合。按改良Mayo腕关节功能评分,优12例,良5例,尚可1例,优良率为94%。结论对急性腕舟骨骨折患者采用经皮闭合复位Herbert螺钉内固定治疗,效果满意,具有疤痕小,重返工作时间短的优势。  相似文献   
38.
Wang Y  Zhao Z  Ren Z  Zhao B  Zhang L  Chen J  Xu W  Lu S  Zhao Q  Peng J 《Neuroscience letters》2012,514(1):96-101
Chemical-extracted acellular nerve allografting, containing the natural nerve structure and elementary nerve extracellular matrix (ECM), has been used for peripheral nerve-defect treatment experimentally and clinically. However, functional outcome with acellular nerve allografting decreases with increased size of gap in nerve defects. Cell-based therapy is a good strategy for repairing long nerve defects. Bone-marrow-derived mesenchymal stem cells (BMSCs) and adipose-derived mesenchymal stem cells (ADSCs) can be induced to differentiate into cells with Schwann cell-like properties (BMSC-SCs or ADSC-SCs), which have myelin-forming ability in vitro and secrete trophic nerve growth factors. Here, we aimed to determine whether BMSC-SCs or ADSC-SCs are a promising cell type for enriching acellular grafts in nerve repair. We evaluated axonal regeneration distance by immunofluorescence staining after 2-week implantation. We used functional and histomorphometric analysis to evaluate 3-month regeneration of the novel cell-supplemented tissue-engineered nerve graft used to bridge a 15-mm-long sciatic nerve gap in rats. Introducing BMSC-SCs or ADSC-SCs to the acellular nerve graft promoted sciatic nerve regeneration and functional recovery. Nerve regeneration with BMSC-SCs or ADSC-SCs was comparable to that with autografting and Schwann cells alone and better than that with acellular nerve allografting alone. Differentiated bone-marrow-or adipose-derived MSCs may be a promising cell source for tissue-engineered nerve grafts and promote functional recovery after peripheral nerve injury.  相似文献   
39.
BACKGROUND: Effects of 17beta-estradiol and progesterone on rhesus monkey oocyte maturation in vitro were evaluated by embryo development subsequent to IVF. METHODS AND RESULTS: In experiment 1, immature cumulus-oocyte complexes collected from unstimulated adult females during the non-breeding season were matured in modified medium CMRL-1066 containing various combinations of gonadotrophins (FSH + LH), estradiol and/or progesterone. Formation of morulae and blastocysts was greatest in oocytes matured in medium containing estradiol and/or progesterone, with or without gonadotrophins (morula 38-46%, blastocyst 14-20%) than in control oocytes matured without estradiol or progesterone (morula 14%, blastocyst 0%). In experiment 2, cumulus-oocyte complexes from unstimulated prepubertal female monkeys were matured in medium with gonadotrophins, estradiol or progesterone. The best development to the morula stage was obtained with oocytes matured with gonadotrophins and estradiol or gonadotrophins and progesterone (43 and 25 morulae, respectively), while control oocytes matured with gonadotrophins but without steroid hormones gave the poorest morula developmental response (12%). However, there was no difference in blastocyst development across all groups (0-3%). CONCLUSIONS: These results demonstrate that during rhesus monkey oocyte maturation in vitro: (i) estradiol or progesterone can improve oocyte developmental competence; (ii) immature oocytes from prepubertal versus adult females have differential responses to challenge with estradiol or progesterone.  相似文献   
40.
目的 本研究旨在通过检测脂多糖(lipopolysaccharide ,LPS)作用后人非小细胞肺癌耐药株细胞内核转录因子(nuclear factor-κB,NF)-κB p65表达量的变化,探讨LPS作用下NF-κB表达量的增高与吉非替尼获得性耐药产生的相关性.方法 成功诱导非小细胞肺癌细胞株HCC827对吉非替尼产生稳定的获得性耐药后,按设置的分组用LPS及吉非替尼处理细胞,采用CCK-8法检测处理后吉非替尼对细胞的半数抑制浓度(IC50值),并与各自对照组相比较.细胞增殖曲线显示LPS作用对细胞增殖的影响.采用克隆形成实验显示LPS作用后对细胞增殖的影响.采用蛋白质印迹法检测LPS及吉非替尼处理后耐药株HCC827/GR-8-1细胞中凋亡相关蛋白caspase-3、Bcl-2等蛋白的表达量,并检测NF-κB蛋白的表达量,探讨LPS作用后激活的NF-κB对细胞吉非替尼敏感性的调节.结果 LPS处理后,可以显著降低耐药细胞对吉非替尼的敏感性,细胞克隆形成实验及增殖曲线显示LPS并无明显促进细胞的增殖作用,但可以降低细胞对吉非替尼的敏感性.蛋白质免疫印迹结果显示,与对照组相比较,LPS可抑制Caspase-3等相关促凋亡蛋白的表达,而相应凋亡抑制蛋白Bcl-2的表达上升.LPS处理48 h后NF-κB的表达量显著上调.LPS通过调节NF-κB表达量上升而参与细胞耐药机制的产生.结论 经LPS作用后的非小细胞肺癌细胞对吉非替尼敏感性降低,LPS处理后细胞的NF-κB表达量显著增高,增高的NF-κB表达量与细胞对吉非替尼的药物敏感性下降相关.  相似文献   
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