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71.
Platelets have diverse roles in immune processes in addition to their key functions in haemostasis and thrombosis. Some studies imply that platelets may be possibly related to the immune tolerance induction. However, the role of platelets in the development of immune tolerance is not fully understood. The purpose of this study was to investigate the role of platelets in the development of regulatory mechanisms responsible for cutaneous inflammation using a mouse model of low zone tolerance (LZT). Mice were treated with 2,4,6‐trinitro‐1‐chlorobenzene (TNCB) 8 times every other day for tolerance induction with administration of anti‐platelet antibody or control antibody during the tolerance induction phase every 3 days. After the treatment for the tolerance induction, mice were sensitized and then challenged with TNCB. The contact hypersensitivity (CHS) was significantly decreased at 24 hours after challenge in the mice with LZT than in those without LZT. Platelet depletion via administration of anti‐platelet antibody reversed the inhibition of CHS and reduced the frequency of Foxp3+ Tregs in the inflamed skin and draining lymph nodes in mice with LZT. In addition, repeated low‐dose skin exposure resulted in elevated plasma levels of transforming growth factor (TGF)‐β1. Interestingly, platelet depletion reduced plasma TGF‐β1 levels of mice with LZT. Furthermore, the CHS response was reduced by administration of recombinant TGF‐β1 during platelet depletion in mice with LZT. Administration of anti‐TGF‐β antibody reversed the inhibition of the CHS responses. These results suggest that platelets are involved in the induction of immune tolerance via the release of TGF‐β1.  相似文献   
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<正>机体的血钾参与并维持细胞代谢,保持细胞内液渗透压及酸碱平衡,并可维持神经肌肉组织兴奋及心肌功能~([1-2])。中重度低血钾主要表现为肌无力,可延及机体的躯干和呼吸肌,造成呼吸困难,还可引发腱反射减弱或消失、肠麻痹及心脏传导阻滞、节律异  相似文献   
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视网膜色素变性(retinitis pigmentosa,RP)的治疗目前仍处于探索阶段。胶质细胞源性神经营养因子(glial cell line-derived neurotrophic factor,GDNF)是目前研究中重要的神经营养因子,但其传统给药方式生物利用度相对较低。近年来GDNF安全有效的给药方式成为研究热点,包括经病毒载体或非病毒载体的基因工程法释药技术、经聚合物释放系统释药技术、经细胞移植释药技术、小分子触发器诱导产生GDNF等。本文就GDNF干预RP的给药方式进行综述。  相似文献   
78.
Objectives: To investigate the impact of EGFR mutations on the efficacy of definitive chemoradiotherapy (CRT) in patients with locally advanced unresectable stage III NSCLC.

Methods: PubMed and EMBASE were searched for eligible studies. Efficacy outcomes included objective response rate (ORR), overall disease progression, local-regional recurrence (LRR), distant progression (DP), brain metastasis, progression-free survival (PFS) and overall survival (OS). Meta-analysis was performed when relevant data were available.

Results: The authors identified seven eligible studies including 695 patients. No significant difference was detected in ORR (Risk Ratio [RR] 1.13, 95% confidence interval [CI] 0.91–1.39, P = 0.28) and overall disease progression (RR 1.06, 95% CI 0.95–1.19, P = 0.29) between EGFR-mutant and EGFR-wild-type groups. EGFR-mutant group had significantly lower LRR (RR 0.49, 95% CI 0.33–0.72, P < 0.01), higher DP (RR 1.36, 95% CI 1.18–1.55, P < 0.01) and higher brain metastasis (RR 2.48, 95% CI 1.46–4.20, P < 0.01) than the EGFR-wild-type group. No sufficient data were available to perform pooled analysis regarding PFS and OS.

Conclusion: For patients with locally advanced unresectable stage III NSCLC treated with definitive CRT, the presence of EGFR mutations may be indicative of lower locoregional recurrence and higher distant progression, especially brain metastasis.  相似文献   

79.
The pituitary tumor-transforming gene 1 (PTTG1), also known as Securin, is considered an oncogene. This study aimed to investigate the role of PTTG1 in clear cell renal cell carcinoma (ccRCC) using in silico bioinformatics approaches. A pan-cancer analysis using The Cancer Genome Atlas (TCGA) data indicated that among all cancer types copy number amplification of PTTG1 gene was most frequently found in ccRCC. However, amplification of PTTG1 gene copy number did not correlate with the increase of mRNA level in ccRCC, and did not predict the patients' overall survival. Instead, ccRCC was correlated with overexpression of PTTG1 mRNA, and its expression level was stage-dependent increased in cancer patients. An outlier analysis using the Oncomine database suggested that PTTG1 mRNA expression served as a good biomarker for ccRCC. Pathway analysis for upregulated genes enriched in PTTG1-high expressing ccRCC patients found that PTTG1 overexpression was associated with mitotic defects. Mining drug sensitivity data using the Cancer Therapeutics Response Portal (CTRP) discovered that PTTG1-high expressing ccRCC cell lines were susceptible to a Rac1 (Ras-related C3 botulinum toxin substrate 1) inhibitor NSC23766. Therefore, this study provides an in silico insight into the role of PTTG1 in ccRCC, and repurposes the Rac1 inhibitor NSC23766 for treating PTTG1-high expressing ccRCC.  相似文献   
80.
Ovarian carcinoma is one of the most lethal malignancies, but only very few prognostic biomarkers are known. The degradome, comprising proteases, protease non-proteolytic homologues and inhibitors, have been involved in the prognosis of many cancer types, including ovarian carcinoma. The prognostic significance of the whole degradome family has not been specifically studied in high-grade serous ovarian cancer. A targeted DNA microarray known as the CLIP-CHIP microarray was used to identify potential prognostic factors in ten high-grade serous ovarian cancer women who had early recurrence (<1.6 years) or late/no recurrence after first line surgery and chemotherapy. In women with early recurrence, we identified seven upregulated genes (TMPRSS4, MASP1/3, SPC18, PSMB1, IGFBP2, CFI – encoding Complement Factor I – and MMP9) and one down-regulated gene (ADAM-10). Using immunohistochemistry, we evaluated the prognostic effect of these 8 candidate genes in an independent cohort of 112 high-grade serous ovarian cancer women. Outcomes were progression, defined according to CA-125 criteria, and death. Multivariate Cox proportional hazard regression models were done to estimate the associations between each protein and each outcome. High ADAM-10 expression (intensity of 2–3) was associated with a lower risk of progression (adjusted hazard ratio (HR): 0.51; 95% confidence interval (CI): 0.29-0.87). High complement factor I expression (intensity 2–3) was associated with a higher risk of progression (adjusted HR: 2.30, 95% CI: 1.17–4.53) and death (adjusted HR: 3.42; 95% CI: 1.72–6.79). Overall, we identified the prognostic value of two proteases, ADAM-10 and complement factor I, for high-grade serous ovarian cancer which could have clinical significance.  相似文献   
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