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51.
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   

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MicroRNAs play important roles in osteoporosis and show great potential for diagnosis and therapy of osteoporosis. Previous studies have demonstrated that miR-146a affects osteoblast (OB) and osteoclast (OC) formation. However, these findings have yet to be identified in vivo, and it is unclear whether miR-146a is related to postmenopausal osteoporosis. Here, we demonstrated that miR-146a knockout protects bone loss in mouse model of estrogen-deficient osteoporosis, and miR-146a inhibits OB and OC activities in vitro and in vivo. MiR-146a−/− mice displayed the same bone mass as the wild type (WT) but exhibited a stronger bone turnover than the WT did under normal conditions. Nevertheless, miR-146a−/− mice showed an increase in bone mass after undergoing ovariectomy (OVX) compared with those subjected to sham operation. OC activities were impaired in the miR-146a−/− mice exposed to estrogen deficiency, which was diametrically opposite to the enhanced bone resorption ability of WT. Macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) from a bone microenvironment affect this extraordinary phenomenon. Therefore, our results implicate that miR-146a plays a key role in estrogen deficiency–induced osteoporosis, and the inhibition of this molecule provides skeleton protection. © 2019 American Society for Bone and Mineral Research.  相似文献   
54.

Background and aims

Potential associations of vegetarian diet patterns with fasting insulin (FI) and insulin sensitivity remain unclear. We aimed to investigate whether vegetarian diets were associated with FI and insulin sensitivity in a cross-sectional study in Chinese vegetarians and matched omnivores and then to test whether it is independent of body mass index (BMI).

Methods and results

This study included 279 vegetarians (73 vegans, 206 lacto-ovo-vegetarians) and 279 age- and sex-matched omnivores. Fasting blood glucose (FG) and FI concentrations were measured, and β-cell function (HOMA-β) and insulin resistance index (HOMA-IR) were used to evaluate insulin sensitivity. All blood glucose and insulin sensitivity indices were naturally log-transformed, and multiple-linear regression was used to determine the association between vegetarian diet patterns and insulin sensitivity after adjusting for confounders including BMI, visceral fat area, physical activity, sedentary time, income, alcohol consumption, and daily dietary intakes of macronutrients. Compared to omnivores, both vegan diet [β = ?0.25, 95% CI: (?0.38, ?0.14)] and lacto-ovo-vegetarian diet [β = ?0.10, 95% CI: (?0.18, ?0.01)] were negatively associated with HOMA-IR after adjusting for BMI. Vegan diet remained negatively associated with FI [β = ?0.16, 95% CI: (?0.30, ?0.01)] and HOMA-IR [β = ?0.17, 95% CI: (?0.32, ?0.03)] after adjusting for all confounders.

Conclusion

Vegetarian diet, especially vegan diet, is negatively associated with FI and IR, independent of BMI.  相似文献   
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目的 初步评估IMRT对无法手术ⅣA期胸腺瘤的疗效及安全性。方法 回顾分析2010-2017年间15例无法手术接受IMRT的ⅣA期胸腺瘤患者,其中男9例、女6例,中位数59岁。PTV、CTV、GTV放疗剂量分别为50、60、70Gy分15~20次,分析近期疗效、总生存率及不良反应。结果 中位随访时间48个月,近期部分缓解率93%(14/15),1、3、5年总生存率分别为100%、75%、75%,仅1例出现3级血液系统反应。4例死亡患者均为肿瘤相关死亡。结论 初步证明ⅣA期胸腺瘤IMRT疗效较好、安全性高,可作为无法手术治疗的胸腺瘤患者安全、有效的治疗手段。  相似文献   
58.
自2019年12月新型冠状病毒感染暴发以来,我国政府采取了严格的防控措施,国内疫情已得到初步控制,但形势依然严峻,境外多个国家也相继出现疫情。根据世界卫生组织的报告:截至2020年3月5日,全球共报告95333例确诊病例(其中我国累计报告确诊病例80565例),85个国家有确诊病例报告,中国将面临输入性病例的传播风险,这为防治我国儿童的疾病疫情提出了新的挑战[1]。在这次疫情中,与成人病例相比,儿童病例相对较少、症状轻、预后较好。目前国内病例数据显示,18岁以下儿童占所有报告病例的2.4%,尚无死亡病例报告[2]。  相似文献   
59.
Randomized controlled trials, being published in English and investigating the associations of at least 4 weeks intervention of citrus and/or its extracts on weight loss among adults, were searched from PubMed, Web of Science, Scopus, and Cochrane by June 2019 to conduct a meta‐analysis. Thirteen articles, including 921 participants, were selected and evaluated by modified Jadad scale. Pooled results by the random‐effects model showed that citrus and/or its extracts administration significantly reduced 1.280 kg body weight (95% CI: ?1.818 to ?0.741, p = 0.000, I2 = 81.4%), 0.322 kg/m2 BMI (95% CI: ?0.599 to ?0.046, p = 0.022, I2 = 87.0%), 2.185 cm WC (95% CI: ?3.804 to ?0.566, p = 0.008, I2 = 98.3%), and 2.137 cm HC (95% CI: ?3.775 to ?0.500, p = 0.011, I2 = 96.2%), respectively, but no significantly decreased effects on WHR and body fat were observed. Subgroup analysis deduced the different effects of study location, intervention duration on body weight associated indices. No publication bias was observed. Our meta‐analysis supported the beneficial effects of citrus and/or its extracts supplement on body weight control, and future well‐designed studies are required to firmly establish the clinical efficacy of citrus and/or its extracts intervention on body weight.  相似文献   
60.
目的:探讨新生血管特异性结合肽GX1二聚体对胃癌新生血管生成的影响。方法:化学合成GX1二聚体、GX1单体、对照肽二聚体,CCK-8实验、管状结构形成实验、迁移实验研究GX1二聚体对胃癌血管内皮细胞(co-HUVEC)增殖、微管形成、迁移能力的影响,流式细胞学技术分析其对细胞周期分布和凋亡的影响。结果:CCK-8结果显示,GX1二聚体与对照肽二聚体及PBS对照组相比,100~200 μmol/L可抑制co-HUVEC增殖,具有统计学差异(P<0.05),并呈剂量依赖性,GX1二聚体较单体抑制作用增强,并有统计学差异(P<0.05)。管状结构形成实验、细胞损伤迁移实验结果显示,与对照肽二聚体及对照组PBS 相比,GX1二聚体及GX1单体,均可抑制胃癌内皮细胞管状结构的形成及迁移,且二聚体抑制作用强于单体;对照肽二聚体仅有轻微的抑制胃癌内皮细胞管状结构的形成及迁移。流式细胞术分析显示,与对照肽二聚体及PBS对照组相比,GX1二聚体及GX1单体均可诱导细胞凋亡(P<0.05),且GX1二聚体的诱导作用强于GX1单体(P<0.05),而对细胞周期分布则无明显影响。结论:GX1二聚体和GX1单体均可抑制胃癌新生血管内皮细胞增殖、微管形成、迁移能力及诱导凋亡,且GX1二聚体较GX1单体作用增强。GX1二聚体有望代替单体成为胃癌新生血管靶向治疗小肽类药物。  相似文献   
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