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101.
Background: Oral submucous fibrosis (OSF) is a chronic debilitating condition characterized by juxta-epithelial fibrosis. The main etiological agent associated with the high-risk precancerous condition is areca nut use. S100A7 is a member of the largest calcium-binding proteins exclusively found in vertebrates and are associated with the regulation of numerous intracellular and extracellular functions. The aim of this study was to investigate the expression of protein S100A7 in salivary samples of individuals with stage I OSF and healthy controls. Methods: This study included 63 participants, 30 of whom had OSF stage I and 33 healthy controls. Nonprobability quota sampling technique was utilized for recruitment of the study participants. A structured baseline questionnaire was used to collect demographic data. Saliva samples were collected by passive droll technique in a sterile container. Salivary levels of S100A7 were quantified by enzyme-linked immunosorbent assay. For the normality of the data Shapiro Wilk test was performed. Student t-test was commuted to evaluate the expression of S100A7 protein expression between both the study groups. Results: The mean salivary S100A7 value for stage I OSF group was 0.334 ng/ml, compared to 0.172 ng/ml for healthy controls. Student t-test reported a statistically significant difference, indicating higher levels of S100A7 in stage I OSF group than in healthy controls (p < 0.001). In the individual group analysis, a significant negative correlation was found between salivary S100A7 and duration of areca nut use (r = –0.45, p = 0.009) and gutka chewing (r = –0.20, p = 0.03), while a significant positive correlation was found between salivary S100A7 and mouth opening (r = 0.03, p = 0.04). Conclusions: Higher levels of S100A7 protein level was seen in stage I OSF group in comparison to the healthy individuals. Results of our study suggest that S100A7 could be used as a surrogate assessment to identify patients at risk of OSF development.  相似文献   
102.
Background: Paraoxonase 1 (PON1), a multifactorial antioxidant enzyme, has a defensive role against oxidative stress, which is believed to contribute to cancer development. This study aimed to investigate the association of PON1-L55M functional polymorphism with breast cancer risk. Material and methods: In the experimental study, blood samples were collected from 150 healthy women controls and 150 breast cancer subjects. The L55M genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. Results: Our analysis showed that the genotypes distribution is in Hardy-Weinberg equilibrium for both case and control groups. Our data revealed that there are significant associations between PON1-L55M polymorphism and breast cancer risk in homozygote (OR= 2.13, 95%CI= 1.14-4.00, p= 0.018), dominant (OR= 1.72, 95%CI= 1.07-2.76, p= 0.024), and allelic (OR= 1.55, 95%CI= 1.12-2.15, p= 0.008) models. Conclusions: Our results suggest that the PON1-L55M genetic variation could be a genetic risk factor for breast cancer risk and it could be considered as a molecular biomarker for screening of susceptible women.  相似文献   
103.
ABSTRACT

Background

The link of acute pancreatitis (AP) with Incretin based therapies (IBTs) in type 2 diabetes has existed since United States Food and Drug Administration alert in 2010. This issue still remains unresolved due to conflicting results among studies.  相似文献   
104.
Telomeric repeat‐containing RNA (TERRA) is closely involved in the regulation of telomere length, which plays critical roles in tumorigenesis. However, the biological significance of TERRA in hepatocellular carcinoma (HCC) remains largely unknown. In this study, we found that HCC cells show a frequent downregulation of TERRA and its positive regulator TTAGGG repeat binding factor‐1 (TRF1), whereas the negative regulator TTAGGG repeat binding factor‐1 (TRF2) was upregulated. We found that TERRA, TRF1, and TRF2 contributed to poor prognosis of HCC patients. Importantly, we found that the downregulation of TERRA significantly promoted HCC cell growth and metastasis in vitro and in vivo, whereas the upregulation of TERRA showed an opposite effect. Mechanistically, downregulation of TERRA significantly increased telomerase activity and promoted telomere elongation. Moreover, the inhibitory effects of TERRA overexpression on the growth and metastasis of HCC cells were reversed by treatment with TA‐65 that activates telomerase activity. In contrast, the protumor effect of TERRA downregulation was reversed by treatment with TMPyP4 that inhibits telomerase activity. Our findings reveal that TERRA plays a critical role in HCC cell growth and metastasis, indicating that TERRA is a potential therapeutic target for HCC.  相似文献   
105.
106.
目的:探究miRNA-325-3p 及其靶基因细胞角蛋白13(cytokeratin 13,CK13)对鼻咽癌细胞CNE1 的放疗敏感性的影响。方法:通过miRBase、Targetscan 及Microcosm 三大数据库预测miRNA-325-3p 的潜在靶基因,并通过双荧光素酶活性检测实验进行验证,qPCR检测不同放射剂量下鼻咽癌细胞CNE1 中miRNA-325-3p 及其靶基因的表达水平变化,通过克隆形成实验观察不同放射剂量下过表达miRNA-325-3p 及敲低靶基因后CNE1 细胞克隆形成率的变化,流式细胞术验证过表达miRNA-325-3p及敲低靶基因后CNE1 在不同放射剂量下凋亡水平的变化,MTT法检测miRNA-325-3p 过表达和CK13 敲低组鼻咽癌细胞CNE1在不同放射剂量下的细胞存活率以验证其放疗敏感性的变化。结果:CK13 确认为miRNA-325-3p 的潜在靶基因,鼻咽癌细胞CNE1 经放射处理后,miRNA-325-3p 的表达水平显著升高、CK13 的表达水平显著降低(均P<0.05)。miRNA-325-3p 表达量上调和CK13 基因沉默均显著提高CNE1 细胞的存活率[miRNA上调时:(60.14±3.55)% vs(19.23±3.42)%,t=14.37、P<0.01;CK13 沉默时:(76.15±5.13)% vs(28.53±3.68)%,t=13.06、P<0.01]和克隆形成率,降低了凋亡率[miRNA 上调时:(27.95±2.67)% vs(51.68±3.47)%,t=9.39、P<0.01;CK13 沉默时:(20.31±2.62)% vs(38.14±3.83)%,t=6.66、P<0.01]。结论:miRNA-325-3p 能够通过下调靶基因CK13的表达降低鼻咽癌细胞CNE1 对放疗的敏感性。  相似文献   
107.
Gonadal hormones, estrogen and androgen are strongly involved in the control of the bradykinin production. Estrogen may worsen whereas androgen can be part of the long-term prophylactic treatment. In this review, we will describe the potential impact of estrogen in the pathophysiology of hereditary angioedema (HAE). Then we will review the different hormone treatments and their implication on the course of HAE in women and men: contraception, Assisted Reproductive Technology (ART), menopause, hormone dependent cancers in women and men, treatment of hyperandrogenism in women.  相似文献   
108.
109.
目的比较改良经椎间孔入路腰椎椎间融合术(transforaminal lumbar interbody fusion,TLIF)与后路腰椎椎间融合术(posterior lumbar interbody fusion,PLIF)治疗中老年轻中度腰椎滑脱症的手术疗效。方法回顾分析 2015 年 1 月—2017 年 1 月收治的符合选择标准的 106 例轻中度腰椎滑脱症(Meyerding 分度≤Ⅱ度)患者临床资料,根据手术方式不同分为改良 TLIF 组(54 例)及 PLIF 组(52 例)。两组患者性别、年龄、病程、滑脱椎体、Meyerding 分度及滑脱类型等一般资料比较,差异均无统计学意义(P>0.05)。记录并比较两组术中出血量、手术时间、术后引流量、术后卧床时间、住院时间、并发症等围术期相关指标。术前及术后 1 周,1、6、12 个月,末次随访时采用疼痛视觉模拟评分(VAS)和日本骨科协会(JOA)评分评价疼痛及功能改善情况,术前与末次随访时测量滑脱角与椎间隙高度评价椎体滑脱矫正情况,末次随访时根据 Suk 标准判定椎间融合情况。 结果所有患者均获随访,随访时间 A 组 25~36 个月,平均 32.7 个月;B 组 24~38 个月,平均 33.3 个月。改良 TLIF 组术中出血量、手术时间、术后引流量、术后卧床时间和住院时间均显著少于 PLIF 组(P<0.05)。两组患者术后各时间点 VAS 评分和 JOA 评分均较术前显著改善(P<0.05);术后 1、6 个月改良 TLIF 组 VAS 评分和 JOA 评分显著优于 PLIF 组(P<0.05)。两组患者末次随访时滑脱角及椎间隙高度均较术前显著改善(P<0.05);术前及末次随访时两组间滑脱角及椎间隙高度比较差异均无统计学意义(P>0.05)。末次随访时根据 Suk 标准,改良 TLIF 组椎间融合率为 96.3%(52/54),PLIF 组为 98.1%(51/52),两组比较差异无统计学意义(χ2=0.000,P=1.000)。并发症:两组患者切口感染、肺部感染及术后 1 周内健侧神经损伤发生率比较差异均无统计学意义(P>0.05);改良 TLIF 组均未发生术中硬脊膜损伤及术后 1 周内患侧神经损伤,PLIF 组分别发生 4 例(7.7%,P=0.054)和 8 例(15.4%,P=0.002)。 结论改良 TLIF 与 PLIF 手术治疗中老年轻中度腰椎滑脱症疗效肯定,改良 TLIF 手术对脊柱后柱正常结构损伤小、出血量和引流量少,硬脊膜和神经损伤发生率低,可改善术后疼痛,促进患者术后快速康复。  相似文献   
110.
目的糖基化终末产物(AGEs)在糖尿病患者在角膜外伤或接受角膜手术时极易出现角膜上皮愈合延迟甚至不愈的过程中起着关键作用,本文研究维生素A(VA)对以糖基化终末产物AGE-BSA诱导角膜上皮细胞损伤的影响及可能的作用机制。方法以HCE-2细胞为研究对象,AGE-BSA为诱导剂,试剂盒检测VA对细胞凋亡率及线粒体膜电位的影响,荧光显微镜检测细胞内凋亡小体,Western blot检测相关的蛋白表达量。结果VA抑制AGE-BSA诱导的HCE细胞凋亡,调节AGEBSA引起的凋亡相关蛋白的变化。同时,VA与JNK的抑制剂同等程度的减少AGE-BSA诱导的JNK和NF-κB的磷酸化。结论VA可能通过抑制JNK介导的NF-κB炎症通路而起到减少AGE-BSA诱导的角膜上皮细胞凋亡的作用,可以作为糖尿病患者角膜上皮损伤的保护剂。  相似文献   
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