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1.
ObjectiveThe objective of this study was to estimate the antibacterial activity of three different herbal extracts against oral bacteria and their bioactive composition.MethodsUsing the disk diffusion technique, the antibacterial activities of three different extracts (lemongrass, sage, and guava leaf) were evaluated against oral bacteria (Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis). Additionally, the bioactive components of the herbal extracts were assessed by employing the gas chromatography-mass spectrometry technique.ResultsThe sage, lemongrass, and guava leaf extracts suppressed the proliferation of all three tested bacterial strains at different rates. The phytochemical analysis revealed that sage extract possessed the highest content of antioxidants, phenols, and flavonoid compounds. The gas chromatography-mass spectrometry analysis of the tested plants revealed the presence of vital bioactive compounds.ConclusionsLemongrass, sage, and guava leaf extracts have potent antibacterial activities, are rich in bioactive compounds, and could be utilized as natural remedies for the prevention of oral diseases.  相似文献   
2.
环状RNA(circular RNA,circRNA)是广泛存在于多物种细胞中结构稳定、高度保守、表达量丰富、可充当微小RNA海绵、具有剪切和转录调控、亲代基因修饰功能的内源性单链闭合circRNA。circRNA主要通过套索驱动的环化、内含子配对驱动的循环、内含子环化方式合成。在胃癌发生和进展过程中,不同种类的circRNA作用不一致。部分circRNA在胃癌组织中表达上调,通过微小RNA/p53/上皮细胞-间充质转化轴等机制促进胃癌细胞增殖、迁移;相反,部分circRNA在胃癌组织中表达下调,通过与miRNA间的海绵作用抑制胃癌细胞增殖和迁移。目前,已在人类唾液、胃液、血浆等成分中检测出胃癌相关的circRNA,提示circRNA具有作为胃癌诊断标志物的潜力。干预circRNA表达提高抗肿瘤药物敏感度,体外合成具有抑癌基因作用的circRNA,或下调具有癌基因作用的circRNA下游信号蛋白是胃癌治疗的有效手段。circRNA为胃癌的诊断和治疗提供了新的思路。   相似文献   
3.
目的研究红外线照射中药溻渍腹部疗法联合中药食疗对胃癌(gastric carcinoma,GC)化疗患者胃肠道不良反应的影响。方法选取镇平县中医院2019年8月至2021年1月76例GC化疗患者,根据治疗方案不同分为对照组38例和观察组38例。对照组采用常规西医药物治疗,观察组在对照组基础上加用中医疗法(红外线照射中药溻渍腹部疗法联合中药食疗)。比较两组临床疗效、胃肠道不良反应改善时间(纳食减少、腹泻便秘、恶心呕吐)、细胞免疫功能[成熟T淋巴细胞(CD3+)、辅助性T细胞(CD4+)、抑制性T细胞(CD8+)]、血清因子水平[白蛋白(Alb)、生长激素(GH)、转铁蛋白(TRF)]。结果两组治疗后总有效率比较,观察组92.11%高于对照组71.05%(P<0.05);观察组纳食减少、腹泻便秘、恶心呕吐改善时间均短于对照组(P<0.001);治疗后,观察组CD3+、CD4+、CD8+均高于对照组(P<0.05);治疗后,观察组Alb、GH、TRF水平均高于对照组(P<0.001)。结论红外线照射中药溻渍腹部疗法联合中药食疗治疗GC化疗患者胃肠道不良反应临床疗效确切,可有效改善机体细胞免疫功能,缓解患者症状,进一步促进机体营养物质吸收。  相似文献   
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5.
MicroRNAs (miRNAs) have been found to be aberrantly expressed and exert essential roles in the tumorigenesis and progression of gastric cancer (GC). miR-301b-3p has been recognized as a cancer-related miRNA in lung cancer, bladder cancer and hepatocellular carcinoma. However, the function of miR-301b-3p in GC progression and its underlying mechanism have not been studied yet. In this study, we found that miR-301b-3p expression was up-regulated in GC tissues compared to adjacent noncancerous tissues. Furthermore, the elevated levels of miR-301b-3p were detected in GC cell lines (SGC-7901, AGS, MKN-45 and MGC-803) as compared with GES-1 cells. Interestingly, GC tissues from patients with tumor size ≥ 5 cm and advanced tumor stages showed obvious higher levels of miR-301b-3p compared to matched controls. Functionally, miR-301b-3p knockdown prominently inhibited cell proliferation, and induced cell cycle arrest at G1 phase and apoptosis in MGC-803 cells. Meanwhile, ectopic expression of miR-301b-3p conversely regulated these biological behaviors of MKN-45 cells. Next, we found that miR-301b-3p knockdown increased, whereas miR-301b-3p overexpression reduced the expression of zinc finger and BTB domain containing 4 (ZBTB4) in GC cells. Accordingly, luciferase reporter assay identified ZBTB4 as a direct target of miR-301b-3p. ZBTB4 overexpression markedly restrained the growth of MGC-803 cells. More importantly, ZBTB4 silencing partially reversed miR-301b-3p knockdown-induced tumor suppressive effects on MGC-803 cells. In conclusion, we firstly revealed that miR-301-3p was highly expressed in GC and contributed to tumor progression via attenuating ZBTB4, which might provide a novel molecular-targeted strategy for GC treatment.  相似文献   
6.
7.
目的建立以二氯甲烷为溶剂的聚乳酸中丙交酯单体残留的定量检测方法。方法气相色谱法,溶剂为二氯甲烷,内标物为2,6-二甲基-γ-吡喃酮,沉淀剂为丙酮:环己烷=3:16。结果在0.5~10.0μg/ml范围内,峰面积与浓度呈良好的线性关系(r2=0.9990),平均回收率为94.8%。结论本方法准确,重现性好,可用于聚乳酸中残留单体含量的定量检测。  相似文献   
8.
BackgroundGastric cancer (GC) is a leading cause of cancer-related death in the world and most patients have advanced disease upon presentation. The effect of age on prognosis in GC is controversial. We aimed to determine the impact of age on survival in patients with GC.MethodsThis was a retrospective study of the medical records of Lebanese patients diagnosed with GC at the American University of Beirut Medical Center (AUBMC) between 2005 and 2014. Patients were divided into young (<65 years) and older groups (≥65 years). A multivariate analysis was done to determine the independent predictors of survival. Kaplan-Meier method was used for analysis of long-term survival outcomes.ResultsThe sample consisted of 156 patients. The mean age was 62.15 (SD 13.54). Most patients presented with stage 4 disease (62.2%) and poorly differentiated histology (66.4%). The most common symptoms were abdominal pain and weight loss. On bivariate analysis, advanced stage (P=0.02) and higher grade (P=0.04) were associated with increased mortality. Patients <65 years of age were significantly more likely to have poorly differentiated tumours, while patients ≥65 years had more comorbidities (P=0.001). The 5-year DFS were 35% and 37% for patients <65 years of age and ≥65 years of age, respectively (P=0.15).ConclusionsHigher grade and advanced stage are associated with worse survival in patients with GC, but age did not seem to have an impact. Screening high risk patients and early diagnosis are necessary to improve survival.  相似文献   
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10.
Polybrominated diphenyl ethers (PBDEs) were determined in various foodstuffs in Italy and the dietary intake was estimated. PBDEs were detected in all analysed samples at concentrations that spanned over five orders of magnitude. The most abundant congeners were the BDE-209, followed by BDE-47 and BDE-99. Fish oil and milk samples showed the highest PBDE concentrations among all samples. The daily dietary intake values were found to be in good agreement or higher to literature values, impacted mainly from the contribution of the analysed dairy products. The cancer risk values estimated for BDE-209 indicated that this specific risk associated with the studied foodstuffs is limited.Italy is one of the world-leading countries in the production of furniture and clothes and has extremely developed medium enterprise industrial sector, where PBDEs were historically used suggesting that their occurrence may be linked to these activities.  相似文献   
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