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1.
利用生物信息学技术初步探索芫根调控肠道免疫功能的分子生物学机制。方法 选择雄性SPF级BALB/c小鼠18只,随机分为3组,每组6只。SC1组小鼠每只每次灌胃芫根提取液150 μL,SC2组小鼠每只每次灌胃绞碎芫根原浆悬液150 μL,NC组小鼠每只每次灌胃生理盐水150 μL,连续7 d每日灌胃一次。分别取每组小鼠小肠组织样品提取RNA,总RNA的质检合格后,进行转录组测序。按GO功能和KEGG信号通路对差异表达基因聚类分析揭示差异表达高度富集的免疫相关通路。从免疫角度分析芫根灌胃小鼠小肠组织的基因表达变化情况。结果 转录组测序共检测到27733条 mRNA的表达,SC1组与NC组比较,显著差异表达基因1635个,其中上调差异表达基因1236个,下调差异表达基因399个;SC2组与NC组比较,显著差异表达基因2872个,其中上调差异表达基因2233个,下调差异表达基因639个(P<0.05)。按GO功能和KEGG信号通路聚类分析显示差异表达基因在白介素分泌、干扰素反应、T细胞受体信号通路及维生素和脂肪消化吸收等途径的富集度在两个芫根组中均居于前20位(P<0.01),肠黏膜趋化因子CCL20和巨噬细胞极化标志物CD274等免疫蛋白编码基因差异表达显著且同属于上述多个免疫通路。结论 芫根灌胃小鼠小肠的差异表达基因在白介素分泌、干扰素反应、T细胞受体信号通路、营养物质消化吸收等途径高度富集,提示芫根对肠道免疫系统及肠黏膜功能的调节,其中CD274的表达上调和CCL20的表达下调提示诱导M1型巨噬细胞极化和T细胞活化可能是芫根调控免疫和维护肠道正常结构功能的重要途径。  相似文献   
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目的探讨关节镜下半月板成形术(AMP)对膝关节半月板损伤患者血清疼痛因子、一氧化氮(NO)、透明质酸(HA)及关节活动度的影响。方法选取2019年5月—2020年12月收治的90例膝关节半月板损伤为研究对象,根据治疗方法不同分为对照组和治疗组,每组45例。对照组接受保守治疗,治疗组行AMP治疗。比较两组的临床疗效,治疗前后的血清前列腺素E2(PGE2)、5-羟色胺(5-HT)、NO、HA、疼痛视觉模拟评分法(VAS)评分和膝关节活动度。记录两组治疗并发症发生情况。结果治疗组疗效优良率高于对照组(P<0.05)。治疗后,两组血清PGE2、5-HT、NO、HA水平均较治疗前下降,且治疗组低于对照组(P<0.05)。治疗后1、2、3、4周,两组VAS评分均较治疗前降低,且治疗组低于对照组(P<0.05)。治疗后,两组膝关节屈伸活动度均较治疗前升高,且治疗组高于对照组(P<0.05)。两组并发症发生率比较差异无统计学意义(P>0.05)。结论AMP对膝关节半月板损伤疗效良好,可减少疼痛因子生成,控制NO、HA水平,提高关节活动度。  相似文献   
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目的 激素是调控植物活性次生代谢产物合成途径的核心调控因子,内源激素结构多样、含量极低,检测难度高,缺乏高效、准确的检测方法。本研究利用超高效液相色谱串联质谱(UHPLC-MS/MS)技术构建了对黄花蒿中茉莉酸、细胞分裂素、赤霉素、生长素、脱落酸等多类植物内源性激素高效定量检测方法。方法 使用Agilent Poroshell 120 EC-C18(2.7 μm, 3.0×150 mm)色谱柱,流动相为0.05%甲酸水-乙腈溶液,梯度洗脱,采用多反应监测模式验证方法可行性,并对黄花蒿不同器官中植物激素进行定量分析。结果 本方法中检测的16种植物激素均呈良好线性,加样回收率、精密度和稳定性均符合植物样品的测定要求。利用此方法测定青蒿不同器官的激素含量,结果表明脱落酸、茉莉酸、茉莉酸甲酯均在叶中含量较高,赤霉素和生长素在根部含量高,细胞分裂素在叶和茎中含量高。结论 青蒿不同器官的激素测定结果可进一步印证脱落酸、茉莉酸、茉莉酸甲酯在调控青蒿素合成中起着重要作用的相关报道,同时表明该方法检测性良好。本文构建的植物内源性激素的检测方法为进一步探究植物生长发育、抵御外界胁迫的相关机制及次生代谢产物的合成等方面提供了手段。  相似文献   
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《Value in health》2022,25(6):1018-1029
ObjectivesThis study aimed to explore quality-adjusted life-year (QALY) and subsequent cost-effectiveness estimates based on the more physical health–focused EQ-5D 5-level version (EQ-5D-5L) value set for England or cross-walked EQ-5D 3-level version UK value set scores or more mental health recovery-focused Recovering Quality of Life Utility Index (ReQoL-UI), when using alternative within-trial statistical methods. We describe possible reasons for the different QALY estimates based on the interaction between item scores, health state profiles, preference-based scores, and mathematical and statistical methods chosen.MethodsQALYs are calculated over 8 weeks from a case study 2:1 (intervention:control) randomized controlled trial in patients with anxiety or depression. Complete case and with missing cases imputed using multiple-imputation analyses are conducted, using unadjusted and regression baseline-adjusted QALYs. Cost-effectiveness is judged using incremental cost-effectiveness ratios and acceptability curves. We use previously established psychometric results to reflect on estimated QALYs.ResultsA total of 361 people (241:120) were randomized. EQ-5D-5L crosswalk produced higher incremental QALYs than the value set for England or ReQoL-UI, which produced similar unadjusted QALYs, but contrasting baseline-adjusted QALYs. Probability of cost-effectiveness <£30 000 per QALY ranged from 6% (complete case ReQoL-UI baseline-adjusted QALYs) to 64.3% (multiple-imputation EQ-5D-5L crosswalk unadjusted QALYs). The control arm improved more on average than the intervention arm on the ReQoL-UI, a result not mirrored on the EQ-5D-5L nor condition-specific (Patient-Health Questionnaire-9, depression; Generalized Anxiety Disorder-7, anxiety) measures.ConclusionsReQoL-UI produced contradictory cost-effectiveness results relative to the EQ-5D-5L. The EQ-5D-5L’s better responsiveness and “anxiety/depression” and “usual activities” items drove the incremental QALY results. The ReQoL-UI’s single physical health item and “personal recovery” construct may have influenced its lower 8-week incremental QALY estimates in this patient sample.  相似文献   
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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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Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway.  相似文献   
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