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1.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。 相似文献
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《Health & place》2022
PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time. 相似文献
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Dongbing Lai Emma C. Johnson Sarah Colbert Gayathri Pandey Grace Chan Lance Bauer Meredith W. Francis Victor Hesselbrock Chella Kamarajan John Kramer Weipeng Kuang Sally Kuo Samuel Kuperman Yunlong Liu Vivia McCutcheon Zhiping Pang Martin H. Plawecki Marc Schuckit Jay Tischfield Leah Wetherill Yong Zang Howard J. Edenberg Bernice Porjesz Arpana Agrawal Tatiana Foroud 《Alcoholism, clinical and experimental research》2022,46(3):374-383
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Bortezomib is a novel proteasome inhibitor, which has been successfully used to treat mantle cell lymphoma and multiple myeloma. However, the direct effects of bortezomib on acute promyelocytic leukaemia (APL) have not been fully investigated. In the present study, the WST-8 assay, western blotting, flow cytometry, monodansylcadaverine staining and transmission electron microscopy were performed. It was demonstrated that bortezomib treatment induced a time- and dose-dependent decrease in the viability of NB4 cells. Bortezomib treatment induced cell apoptosis in NB4 cells, as assessed by Annexin V/propidium iodide analysis, and the detection of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase, Bax and Bcl-2 expression. Furthermore, bortezomib treatment induced autophagy in NB4 cells, as indicated by autophagosome formation, p62 degradation, LC3-I to LC3-II conversion and formation of acidic autophagic vacuoles. Notably, autophagy induced by bortezomib was initiated prior to apoptosis. Inhibition of autophagy by knocking down Beclin-1 expression increased bortezomib-induced apoptosis in NB4 cells. Therefore, the present study revealed that the combination of bortezomib and autophagy inhibition may be a potential treatment strategy for APL. 相似文献
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《Research in social & administrative pharmacy》2022,18(9):3694-3698
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area. 相似文献
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