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991.
1. Aldehyde oxidase (AO enzymes)-mediated oxidation predominantly occurs at a carbon atom adjacent to the nitrogen on aromatic azaheterocycles. In the current report, we identified that AO enzymes oxidation took place at both the C-2 and C-4 positions of the methylquinoline moiety of Compound A based on data from mass spectrometric analysis, AO enzymes “litmus” test, and comparison with authentic standards.

2. To assess the potential for inadequate coverage for these two AO enzyme-mediated metabolites in nonclinical safety studies, given concerns due to differences in AO enzymes expression between preclinical species and humans, the human circulating levels of the two AO enzyme-mediated metabolites were predicted prospectively using in vitro and in vivo models. Both formation clearance and elimination clearance of the two metabolites were predicted based on in vitro to in vivo correlation and comparison with in vivo data from rats.

3. The result showed that the 4-OH metabolite of Compound A would account for less than 3% of the total drug-related exposure in human plasma, while the exposure to the 2-oxo metabolite would be relatively high (~70%).

4. The predicted human exposure levels for the two metabolites are in similar ranges as those observed in monkeys. These data taken together support the advancement to clinical development of Compound A.  相似文献   

992.

Background

Polybrominated diphenyl ethers (PBDEs) are major brominated flame retardant (BFR) chemicals with endocrine-disrupting properties. One small-scale study on humans has suggested that prenatal exposure to PBDEs is adversely related to anogenital distance (AGD) a sensitive marker for prenatal androgen exposure. The aim of the present study was to examine the associations between prenatal exposure to PBDEs and AGD among boys 0–4 years of age in a cohort study.

Methods

In the Shanghai-Minhang Birth Cohort Study (S-MBCS), nine PBDE congeners were measured in cord plasma of 192 male infants. We measured anopenile distance (AGDAP) and anoscrotal distance (AGDAS) at birth, 6 months, 12 months, and 48 months of age. A total of 190 boys with neonatal concentrations of PBDEs (ng/g lipid) who had at-least one AGD measurement were included in our study. Information on potential confounding variables were collected through in-person interviews. Multiple linear regression models and generalized estimating equation (GEE) models were used to evaluate the associations between prenatal PBDEs concentrations and AGD.

Results

Among the nine congeners, BDE-47 had the highest detection rate (83.68%) and the highest median concentration (0.18?ng/g lipid). Boys who had neonatal concentration of BDE-47 or Σ4PBDEs (sum of BDE-47, BDE-99, BDE-100, and BDE-153) in the higher quartile generally had shorter AGDAP and AGDAS than those in the first quartile. Significant inverse associations were found between AGDAS and fourth quartile BDE-47 levels among boys 12 months and 48 months of age (β?=??5.57, 95% confidence interval (CI): ?9.89, ?1.25 for 12 month of age; β?=??4.32, 95% CI: ?8.18, ?0.46 for 48 month of age). Inverse associations were also observed between AGDAS and fourth quartile Σ4PBDEs levels among boys 12 months of age (β?=??5.13, 95% CI: ?9.89, ?1.25). In GEE models, similar patterns of association were also observed between BDE-47 and AGDAS.

Conclusions

Our findings provide preliminary evidence that prenatal exposure to BDE-47 and Σ4PBDEs, even at low environmental levels, may be associated with shorter AGD in boys. This data suggest that prenatal exposure to PBDEs may have adverse effects on male reproductive development. Further studies should be conducted to validate these results.  相似文献   
993.
The protozoan pathogen Cryptosporidium is an important cause of diarrhoeal disease, but in many contexts its burden remains uncertain. The Global Waterborne Pathogen model for Cryptosporidium (GloWPa-Crypto) predicts oocyst concentrations in surface water at 0.5 by 0.5° (longitude by latitude) resolution, allowing us to assess the burden specifically associated with the consumption of contaminated surface water at a large scale. In this study, data produced by the GloWPa-Crypto model were used in a quantitative microbial risk assessment (QMRA) for sub-Saharan Africa, one of the regions most severely affected by diarrhoeal disease. We first estimated the number of people consuming surface water in this region and assessed both direct consumption and consumption from a piped (treated) supply. The disease burden was expressed in disability adjusted life years (DALYs). We estimate an annual number of 4.3 × 107 (95% uncertainty interval [UI] 7.4 × 106–5.4 × 107) cases which represent 1.6 × 106 (95% UI 3.2 × 105–2.3 × 106) DALYs. Relative disease burden (DALYs per 100,000 persons) varies widely, ranging between 1.3 (95% UI 0.1–5.7) for Senegal and 1.0 × 103 (95% UI 4.2 × 102–1.4 × 103) for Eswatini. Countries that carry the highest relative disease burden are primarily located in south and south-east sub-Saharan Africa and are characterised by a relatively high HIV/AIDS prevalence. Direct surface water consumption accounts for the vast majority of cases, but the results also point towards the importance of stable drinking water treatment performance. This is, to our knowledge, the first study to utilise modelled data on pathogen concentrations in a large scale QMRA. It demonstrates the potential value of such data in epidemiological research, particularly regarding disease aetiology.  相似文献   
994.
Health systems guidance (HSG) documents contain systematically developed statements or recommendations intended to address a health system challenge. The concept of HSG is fairly new and considerable effort has been undertaken to build tools to support the contextualization of recommendations. One example is the Appraisal of Guidelines for REsearch and Evaluation - Health Systems (AGREE-HS), created by international stakeholders and researchers, to assist in the development, reporting and evaluation of HSG. Here, we present the quality appraisal of 85 HSG documents published from 2012 to 2017 using the AGREE-HS. The AGREE-HS consists of five items (Topic, Participants, Methods, Recommendations, and Implementability), which are scored on a 7-point response scale (1=lowest quality; 7=highest quality). Overall, AGREE-HS item scores were highest for the 'Topic' and 'Recommendations' items (means above the mid-point of 4), while the 'Participants', 'Methods', and 'Implementability' items received lower scores. Documents without a specific health focus and those authored by the National Institute for Health and Care Excellence group, achieved higher AGREE-HS overall scores than their comparators. No statistically significant changes in overall scores were observed over time. This is the first time that the AGREE-HS has been applied, providing a current quality status report of HSG and identifying where improvements in HSG development and reporting can be made.  相似文献   
995.
996.
目的:探讨NFASC在胃癌中的预后意义及相关机制。方法:从人类肿瘤相关基因表达汇编(Gene Expression Omibus,GEO)数据库中下载GSE62254胃癌数据集,分析NFASC表达与胃癌临床病理学参数的相关性及对预后的影响;利用Cox模型分析影响胃癌患者总生存期的因素并建立预后预测列线图模型;采用基因集富集分析(GSEA)方法预测NFASC参与的信号通路。结果: NFASC高表达的胃癌患者总生存时间(overall survival,OS)更短(P<0.05),NFASC表达与患者年龄、T分期及Lauren分型相关(P均<0.05)。NFASC高表达富集了TGF-β信号通路、mTOR信号通路、MAPK信号通路和Wnt信号通路等与肿瘤细胞增殖密切相关的通路(P<0.05,FDR<0.25)。结论: NFASC是胃癌的不良预后因素,其表达可能成为胃癌预后预测生物标志物。  相似文献   
997.
侯阳阳  陈雪丹 《新中医》2020,52(3):181-183
目的:观察耳穴贴压联合中医饮食调护对糖尿病肾病患者的影响。方法:将糖尿病肾病患者60例按随机数字表法分成2组,对照组30例患者采用耳穴贴压治疗,观察组30例患者采用耳穴贴压联合中医饮食调护治疗。对比2组患者治疗前后肾功能指标、血清糖化血红蛋白、尿微量白蛋白、24h尿蛋白定量变化和肾小管损伤情况。结果:2组治疗后,血尿素氮(BUN)、内生肌酐清除率(CCr)、24 h尿白蛋白排泄率(UAE)和血肌酐(SCr)水平均明显优于治疗前,差异有统计学意义(P<0.05);治疗后,观察组肾功能指标BUN、CCr、UAE低于对照组,SCr则有所提高,差异有统计学意义(P<0.05)。2组患者治疗后,尿蛋白定量、尿微量白蛋白和血清糖化血红蛋白水平均明显优于治疗前,差异有统计学意义(P<0.05);观察组治疗后尿蛋白、尿微量白蛋白、血清糖化血红蛋白指标低于对照组,差异有统计学意义(P<0.05)。2组患者治疗后,β2-微球蛋白(β2-MG)和N-乙酰-β-D-氨基葡萄糖苷酶(NAG)水平均明显优于治疗前,差异有统计学意义(P<0.05);观察组治疗后肾小管损伤指标β2-MG、NAG低于对照组,差异有统计学意义(P<0.05)。结论:耳穴贴压联合中医饮食调护在糖尿病肾病患者中疗效明确,可改善肾功能指标,减轻肾小管损伤,改善临床症状。  相似文献   
998.
翟春苗  许燕飞  叶俏慧 《新中医》2020,52(5):140-142
目的:观察腰痛散循经火疗治疗寒湿腰痛的临床疗效。方法:选取寒湿腰痛患者60例,按随机数字表法分为治疗组和对照组各30例。对照组采用腰痛散湿热敷,治疗组在对照组湿热敷的基础上运用腰痛散循经火疗。采用疼痛数字评分法(NRS)和日本骨科协会评估治疗分数(JOA)分别对2组患者进行客观评价,比较2组临床疗效。结果:治疗组总有效率为96.66%,显著高于对照组73.33%(P<0.05)。治疗前,2组NRS评分、JOA评分比较,差异均无统计学意义(P>0.05)。治疗后,2组NRS评分较治疗前降低,JOA评分较治疗前升高(P<0.05);且治疗组NRS评分低于对照组,JOA评分高于对照组(P<0.05)。结论:腰痛散循经火疗治疗寒湿腰痛效果显著,症状改善明显,安全有效,进一步提高了患者的生活质量。  相似文献   
999.
目的:探讨红景天苷(salidroside,SAL)对树突状细胞(dendritic cell,DC)表型及细胞毒性T细胞(cytotoxic T lympho‐cyte,CTL)抗肿瘤能力的影响。方法:选用Lewis肺癌细胞株3LL、野生型C57BL/6和TLR4-/-C57BL/6小鼠,获取小鼠骨髓来源的DC前体细胞,经过培养分化成未成熟DC,收获第6天的DC,经磁珠分选后获得纯度较高的CD11c+DC。将细胞分成PBS组、SAL组和脂多糖(lipopolysaccharide,LPS)组,培养48 h后用流式细胞术检测SAL体外对DC表面分子、吞噬功能、TLR4通路和对T细胞杀伤能力的影响。结果:与 PBS 组比较,SAL组DC的表面分子CD80、CD86、MHC Ⅱ表达水平显著升高(均 P<0.05)、吞噬功能显著下降(P<0.05)、TLR4 表达水平显著升高(P<0.01);与野生型组比较,TLR4-/-组DC经SAL或LPS处理后,其表面分子CD80、CD86、MHC Ⅱ的表达水平显著降低(均P<0.05);与PBS组比较,SAL组刺激活化的CTL对肺癌3LL细胞的杀伤效应显著升高(P<0.05)。结论:SAL可以通过调控TLR4诱导DC成熟,从而提高T细胞的杀伤能力  相似文献   
1000.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.  相似文献   
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