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目的 建立细叶亚菊的质量标准,为其质量控制和合理开发利用提供科学参考。方法 采用性状鉴别、显微鉴别、薄层色谱法(TLC)对细叶亚菊进行定性分析;参照《中国药典》(2020年版)通则方法对细叶亚菊水分、总灰分、酸不溶性灰分、水溶性浸出物进行含量检查;利用高效液相色谱法(HPLC)测定细叶亚菊中绿原酸、异绿原酸A的含量。结果 确定了细叶亚菊的药材性状及显微特征。TLC鉴别显示,供试品(细叶亚菊药材)与对照品(绿原酸、异绿原酸A)在相应位置上均显示相同颜色的荧光斑点。13批细叶亚菊水分、总灰分、酸不溶性灰分、浸出物的含量分别为8.55%-13.07%、6.81%-12.68%、1.11%-3.53%、8.41%-11.64%;绿原酸、异绿原酸A的含量范围分别为0.072%-0.440%、0.283%-1.324%(n=3)。结论 本研究建立的方法准确稳定,可为细叶亚菊的质量控制提供参考。暂规定细叶亚菊水分不得过12.0%,总灰分不得过10.0%,酸不溶性灰分不得过2.5%,水溶性浸出物不得少于8.0%,绿原酸不得少于0.2%,异绿原酸A不得少于0.6%。 相似文献
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《Revista portuguesa de cardiologia》2022,41(4):311-320
Aims and objectivesVitamin D deficiency is a common finding and there is a suggested association with hypertension. Resistant hypertension is a clinical problem observed in 5–30% of hypertensive patients. Renal denervation (RDN) has been used for patients with resistant hypertension and has proven to lower blood pressure. Our primary goal was to assess the vitamin D serum concentration as a predictor of blood pressure response to RDN in highly selected patients.MethodsThis prospective, nonrandomized, single-center study included 24 patients treated with RDN. Based on their one-year response after RDN, patients were classified as responders or non-responders at six months or at 12 months.ResultsThe median follow-up was 52 months (range, 14-91 months). After RDN, 17 patients (70.8%) had a reduction >5 mmHg in the mean systolic blood pressure, at the first six months of follow-up. At 12 months, 20 patients (83.3%) were responders. Vitamin D levels at baseline (15.1±4.8 vs. 24.2±8.8 ng/ml) and at six months (16.6±7.2 vs. 25±9.2 ng/ml) were lower in early non-responders compared to early responders (p=0.008), without significant variation during follow-up. Even though Vitamin D levels were lower in the total responder's group, no statistically significant differences were found (p=ns).ConclusionIn patients with resistant hypertension, low vitamin D concentrations were associated with an absence of early response to RDN. 相似文献
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《Saudi Pharmaceutical Journal》2022,30(5):595-604
Anthrax is a zoonotic infection caused by the gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. Depending on the origin of the infection, serious health problems or mortality is possible. The virulence of B. anthracis is reliant on three pathogenic factors, which are secreted upon infection: protective antigen (PA), lethal factor (LF), and edema factor (EF). Systemic illness results from LF and EF entering cells through the formation of a complex with the heptameric form of PA, bound to the membrane of infected cells through its receptor. The currently available anthrax vaccines have multiple drawbacks, and recombinant PA is considered a promising second-generation vaccine candidate. However, the inherent chemical instability of PA through Asn deamidation at multiple sites prevents its use after long-term storage owing to loss of potency. Moreover, there is a distinct possibility of B. anthracis being used as a bioweapon; thus, the developed vaccine should remain efficacious and stable over the long-term. Second-generation anthrax vaccines with appropriate adjuvant formulations for enhanced immunogenicity and safety are desired. In this article, using protein engineering approaches, we have reviewed the stabilization of anthrax vaccine candidates that are currently licensed or under preclinical and clinical trials. We have also proposed a formulation to enhance recombinant PA vaccine potency via adjuvant formulation. 相似文献
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Each hepatitis virus—Hepatitis A, B, C, D, E, and G—poses a distinct scenario to the patient and clinician alike. Since the discovery of each virus, extensive knowledge regarding epidemiology, virologic properties, and the natural clinical and immunologic history of acute and chronic infections has been generated. Basic discoveries about host immunologic responses to acute and chronic viral infections, combined with virologic data, has led to vaccines to prevent Hepatitis A, B, and E and highly efficacious antivirals for Hepatitis B and C. These therapeutic breakthroughs are transforming the fields of hepatology, transplant medicine in general, and public and global health. Most notably, there is even an ambitious global effort to eliminate chronic viral hepatitis within the next decade. While attainable, there are many barriers to this goal that are being actively investigated in basic and clinical labs on the local, national, and international scales. Herein, we discuss pertinent clinical information and recent organizational guidelines for each of the individual hepatitis viruses while also synthesizing this information with the latest research to focus on exciting future directions for each virus. 相似文献
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目的探讨维持性血液透析(MHD)患者血清维生素D水平对下肢肌力减退的预测作用。 方法横断面研究设计,选择2018年9月至10月于战略支援部队特色医学中心血液净化中心的95例MHD患者,检测其血清25-羟维生素D3[25(OH)D3]水平,采用5次站立-坐下实验(5-STS)评价其下肢肌力。根据5-STS完成时间将MHD患者分为下肢肌力正常组(n=85)与减退组(n=10),比较两组患者人口学特征、实验室指标。采用多因素Logistic回归分析下肢肌力减退的影响因素,绘制受试者工作特征(ROC)曲线分析上述因素预测MHD患者发生下肢肌力减退的特异度和敏感度。 结果95例MHD患者血清25(OH)D3水平为11.00~99.50 nmol/L,中位数31.23(19.90~43.30)nmol/L;5-STS完成时间为3.55 s~18.71 s,中位数9.81(7.12,12.43)s,下肢肌力减退者10例(10.53%)。多因素Logistic回归分析显示,血清25(OH)D3是MHD患者下肢肌力减退的保护性因素[OR=0.761,95%CI(0.592~0.978),P=0.033]。进一步ROC曲线分析显示,25(OH)D3对应的ROC曲线下面积为0.815,其预测MHD患者发生下肢肌力减退的敏感度为80.00%,特异度为80.00%。 结论MHD患者血清25(OH)D3水平普遍较低,下肢肌力减退者更为明显;血清维生素D水平对MHD患者是否存在下肢肌力减退具有较好的预测价值。 相似文献
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《Human immunology》2022,83(1):74-80
This study aimed to evaluate the immunomodulatory effect of vitamin D (VD) on the NLRP1 and NLRP3 inflammasomes in placental explants from preeclamptic (PE) and normotensive (NT) pregnant women. Placental explants from eight PE and eight NT pregnant women were cultured with or without hydrogen peroxide (H2O2), VD or H2O2 + VD. Gene and protein expression of NLRP1, NLRP3, HMGB1, caspase-1, IL-1β, TNF-α and IL-18 were determined by qPCR and Western blotting/ELISA. Compared to NT pregnant women, the endogenous gene expression of NLRP1, NLRP3, HMGB1, IL-1β, TNF-α and IL-18 was significantly higher in explants from PE and became decreased after VD treatment. Similarly, VD decreased the protein expression of NLRP1, NLRP3, caspase-1, HMGB1, IL-1β, TNF-α and IL-18 in PE. Placental explants from NT cultured with H2O2 showed increased gene and protein expression of NLRP1, NLRP3, caspase-1, IL-1β, TNF-α and HMGB1, while H2O2 was also able to increase TNF-α and caspase-1 gene expression in PE. Treatment with H2O2 + VD decreased gene/protein expression of NLRP1, NLRP3, caspase-1, HMGB1, IL-1β, TNF-α and IL-18 in PE and NT explants with H2O2. NLRP1 and NLRP3 are upregulated in the PE. VD may play an immunomodulatory role in the placental inflammation and downregulates oxidative stress induced in vitro by H2O2. 相似文献
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目的 基于网络药理学研究香菇多糖抑制三阴乳腺癌(TNBC)的作用机制并采用细胞和动物实验进行验证。方法 通过GeneCards数据库和DisGeNET数据库筛选与TNBC相关基因靶点,利用TCMID、PubChem、SwissTargetPrediction和GeneCards数据库查询香菇多糖相关基因靶点。使用Sangerbox软件进行基因本体论(GO)富集和京都基因与基因组百科全书(KEGG)通路富集分析。结合STRING数据库与Cytoscape 3.7.0软件将共同靶点进行可视化处理,筛选核心靶点,构建"化合物-靶点-通路"网络。利用Metascape软件进行转录因子及相关调控基因特异富集。体外培养小鼠TNBC细胞4T1和人TNBC细胞MDA-MB-231,磺酰罗丹明B染色法观察香菇多糖(31.25、62.5、125、250、500、1 000μg·mL-1)对细胞存活率的影响;健康雌性BABLC小鼠sc接种1×106个4T1-Luc细胞构建TNBC模型,通过小动物活体成像系统观察香菇多糖(100、200 mg·kg-1)对肿瘤生长的影响,实时荧光定量PCR (qRT-PCR)技术检测肿瘤组织信号转导和转录活化因子3(STAT3)和血管内皮生长因子A (VEGFA) mRNA表达。结果 数据库及软件分析得到香菇多糖治疗TNBC关键靶点52个,靶点主要涉及PI3K-Akt、AGE-RAGE、HIF-1、MAPK信号通路和肿瘤蛋白多糖相关通路,PPI分析得到VEGFA、STAT3、MAPK1、IL2、TNF、RELA、AKT1、MAPK3、BCL2L1和HSP90AA1 10个hub基因。与对照组比较,香菇多糖对4T1和MDA-MB-231细胞存活率均有显著抑制作用(P<0.05、0.01),且作用呈浓度相关性;在给药14、21d后,与模型组比较,香菇多糖能够剂量相关性地抑制小鼠TNBC肿瘤的生长,高剂量组差异显著(P<0.05、0.01),21 d抑制率达到(91.9±4.7)%;与对照组比较,香菇多糖给药后能够剂量相关性抑制STAT3和VEGFA的mRNA表达,高剂量组差异显著(P<0.05、0.01)。结论 香菇多糖可通过多靶点、多途径协同作用抑制TNBC的生长。 相似文献