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排序方式: 共有1021条查询结果,搜索用时 15 毫秒
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目的 探讨茶多酚对牙齿早期龋进展的影响。方法 采用体外脱矿的方法建立牛牙牙釉质和牙本质早期龋模型。将釉质龋及牙本质龋标本随机分为4组(n=6):空白对照组(DW组)、氟化钠组(NaF组)、茶多酚组(TP组)、茶多酚与氟化钠联合应用组(TP+NaF组),pH循环实验模拟早期龋的进程。检测pH循环后的脱矿液中钙、磷离子浓度,通过显微硬度计检测牙体硬组织表面显微硬度值,X线能谱分析样本表面钙磷比,并测定再矿化液中羟脯氨酸水平。结果 在牙釉质及牙本质的脱矿液中,TP组钙、磷离子相对释放量与DW组差异无统计学意义,明显高于NaF组和TP+NaF组(P<0.05)。TP组牙釉质表面显微硬度值与DW组差异无统计学意义,牙本质表面显微硬度值高于DW组;DW组、TP组牙釉质及牙本质表面显微硬度值均低于NaF组和TP+NaF组(P<0.05)。TP组牙釉质及牙本质表面钙磷比均高于DW组(P<0.05),牙釉质表面钙磷比与NaF组和TP+NaF组差异无统计学意义,牙本质表面钙磷比低于NaF组和TP+NaF组(P<0.05)。NaF组和TP+NaF组牙本质再矿化液中羟脯氨酸水平均低于DW组和TP组(P<0.05),TP组与DW组以及TP+NaF组与NaF组间差异均无统计学意义。结论 在早期龋的进展过程中,茶多酚无明显抑制牙釉质及牙本质脱矿的作用,但可通过促进钙磷离子的再沉积促进再矿化的发生。 相似文献
3.
Tugba Ozdal David A. Sela Jianbo Xiao Dilek Boyacioglu Fang Chen Esra Capanoglu 《Nutrients》2016,8(2)
As of late, polyphenols have increasingly interested the scientific community due to their proposed health benefits. Much of this attention has focused on their bioavailability. Polyphenol–gut microbiota interactions should be considered to understand their biological functions. The dichotomy between the biotransformation of polyphenols into their metabolites by gut microbiota and the modulation of gut microbiota composition by polyphenols contributes to positive health outcomes. Although there are many studies on the in vivo bioavailability of polyphenols, the mutual relationship between polyphenols and gut microbiota is not fully understood. This review focuses on the biotransformation of polyphenols by gut microbiota, modulation of gut microbiota by polyphenols, and the effects of these two-way mutual interactions on polyphenol bioavailability, and ultimately, human health. 相似文献
4.
目的:探讨茶多酚对缺血/再灌注心脏损伤的保护作用,并研究心脏能量代谢和心肌细胞钙内流是否参与了心脏缺血/再灌注损伤的保护作用。方法在大鼠Langendorff离体心脏上实施缺血/再灌注各30 min,用一导管经压力换能器连接放大器记录心功能指标;用31P NMR技术测定心脏的能量代谢,全细胞膜片钳技术记录心肌细胞钙内流。结果与对照组比较,茶多酚(2.5 mg/L)能使缺血/再灌注心脏的心室发展压、左心室压最大收缩速率(+dp/dtmax)、左心室压最大舒张速率(-dp/dtmax)和冠脉流量显著增加(P<0.05),并显著改善缺血/再灌注心脏的能量代谢,增加心肌ATP和PCr含量(P<0.05)。浓度为2.5和5.0 mg/L的茶多酚均能显著抑制培养心肌细胞的钙内流(P<0.01)。结论茶多酚对大鼠离体心脏缺血/再灌注损伤的保护作用可能与其改善心肌能量代谢、抑制心肌细胞钙内流的作用有关。 相似文献
5.
Vilma Pereira Panza Henver Simionato Brunetta Marina Vieira de Oliveira Everson Araújo Nunes 《International journal of food sciences and nutrition》2019,70(2):212-221
Increased superoxide production by phagocytic NADPH oxidase has been associated with inflammatory conditions. Growing evidences suggest that dietary polyphenols may modulate the expression of NADPH oxidase subunits. Herein, we examined whether soluble mate tea (SMT) consumption – a polyphenol-rich beverage – affects the expression of the leukocyte NADPH oxidase protein p47phox and/or circulating biomarkers of inflammation and antioxidant biomarkers in humans. In a two-phase study, nine men were requested to drink water (control) for 8 d and then follow a second 8-d period drinking SMT. Blood samples were analysed for p47phox protein in CD16+/CD14? cells, interleukin (IL)-1β (IL-1β), tumour necrosis factor-alpha (TNF-α), IL-6, total phenols, and reduced and oxidised glutathione (GSH and GSSG, respectively) after each study phase. After SMT intake, CD16+/CD14? cells' p47phox protein and serum TNF-α and IL-6 levels were significantly attenuated (P?<?.05) while plasma phenolic compounds and blood GSH:GSSG ratio were significantly enhanced (P?<?.05). Consumption of SMT favourably affected leukocytes' p47phox expression and inflammatory cytokine and antioxidants levels in peripheral blood, which may help decrease oxidative stress and low-grade inflammation. 相似文献
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7.
A. Zevallos-Concha D. Nuñez M. Gasco C. Vasquez M. Quispe G. F. Gonzales 《Toxicology mechanisms and methods》2016,26(1):67-73
This study was performed to determine the effects of gamma irradiation on UV spectrum on maca, total content of polyphenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and in vivo biological activities of red and black maca extracts (Lepidium meyenii).Adult mice of the strain Swiss aged 3 months and weighing 30–35?g in average were used to determine biological activities. Daily sperm production, effect on testosterone-induced prostate hyperplasia and forced swimming test were used to determine the effect of irradiation on biological activities of maca extracts.Irradiation did not show differences in UV spectrum but improves the amount of total polyphenols in red maca as well as in black maca extracts. In both cases, black maca extract has more content of polyphenols than red maca extract (p?<?0.01). Gamma irradiation significantly increased the antioxidant capacity (p?<?0.05).No difference was observed in daily sperm production when irradiated and nonirradiated maca extract were administered to mice (p?>?0.05). Black maca extract but not red maca extract has more swimming endurance capacity in the forced swimming test. Irradiation of black maca extract increased the swimming time to exhaustion (p?<?0.05). This is not observed with red maca extract (p?>?0.05). Testosterone enanthate (TE) increased significantly the ventral prostate weight. Administration of red maca extract in animals treated with TE prevented the increase in prostate weight. Irradiation did not modify effect of red maca extract on prostate weight (p?>?0.05).In conclusion, irradiation does not alter the biological activities of both black maca and red maca extracts. It prevents the presence of microorganisms in the extracts of black or red maca, but the biological activities were maintained. 相似文献
8.
Fang Liu Deming Li Xinjing Wang Yuan Cui 《International journal of food sciences and nutrition》2021,72(1):14-25
AbstractWhether polyphenols could ameliorate inflammatory bowel disease (IBD) is still conflicting. To explore the efficacy of polyphenols as an adjuvant therapy for IBD, we conducted this systematic review and meta-analysis. Literature search was performed using PubMed, Web of Science, Scopus and Cochrane databases. Finally, 12 randomized controlled trials (RCTs) were included. In contrast to control group, curcumin treatment significantly improved clinical remission in intention-to-treat (ITT) (OR = 3.36, 95% CI: 1.09–10.37) and per-protocol (PP) analysis (OR = 5.13, 95% CI: 1.84–14.27). Meanwhile, curcumin could significantly ameliorate endoscopic remission (OR = 5.69, 95% CI: 1.28–25.27) and clinical response (OR = 4.69, 95% CI: 1.03–21.47) in PP analysis. Heterogeneity was present across the studies. In conclusions, polyphenols might be an effective adjuvant treatment for ameliorating IBD. Considering the relatively few studies included in our present study, further clinical trials are required to verify the effects of polyphenols on IBD. 相似文献
9.
目的:探究槟榔多酚对大鼠肺微血管内皮细胞(PMVEC)低氧损伤的保护作用。 方法:采用氧化应激指标丙二醛和超氧化物歧化酶筛选肺部缺氧损伤细胞模型最适条件;采用细胞计数试剂盒法筛选槟榔多酚最适给药剂量。将PMVEC分为常氧对照组、模型对照组和槟榔多酚组,采用BCA法检测蛋白浓度并测定PMVEC中的氧化应激水平,蛋白质印迹法检测炎症和凋亡相关蛋白的表达,免疫荧光染色法检测闭合蛋白和闭锁小带1等紧密连接蛋白的表达,Transwell小室实验检测跨内皮细胞膜电阻,罗丹明荧光染料检测PMVEC屏障的通透性。 结果:1%氧浓度培养PMVEC细胞 48?h后成功构建肺部缺氧损伤细胞模型 ;20?μg/mL的槟榔多酚可以显著逆转缺氧损伤细胞模型中PMVEC的存活率下降以及氧化应激水平的升高(均 P<0.05);槟榔多酚对于低氧诱导下PMVEC中炎症相关蛋白核因子κB(NF-κB)和核因子E2相关因子(Nrf)2的上调有显著抑制作用(均P<0.05);槟榔多酚可以下调低氧诱导下PMVEC中凋亡相关蛋白胱天蛋白酶(caspase)3、Bcl-2相关X蛋白(Bax)的表达(均P<0.05),从而减轻低氧诱导下细胞的凋亡;槟榔多酚显著上调低氧诱导下PMVEC闭合蛋白和闭锁小带1的表达(均P<0.05),提高跨膜电阻值并降低罗丹明透过量,改善肺微血管内皮屏障的通透性。结论:槟榔多酚可以通过减轻PMVEC的氧化应激损伤、降低炎症相关蛋白表达、减少细胞凋亡及提高细胞屏障的通透性,改善PMVEC的低氧损伤。 相似文献
10.
散发性脑淀粉样血管病(cerebral amyloid angiopathy,CAA)是一种老年人中常见的颅内微血管病。CAA相关病变(如脑出血、认知功能下降等)的发生主要包括淀粉样蛋白沉积于脑血管壁、继发血管损伤两个重要过程,其危险因素包括Apo E基因多态性等遗传因素和高血压病等非遗传因素。免疫治疗和一些天然多酚类物质可防止脑血管内的淀粉样蛋白沉积,而控制高血压等非遗传危险因素或使用依达拉奉能减轻CAA继发血管损伤。这些方法有望成为今后散发性CAA治疗的发展方向。 相似文献