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101.
Yun-Ting He Xiao-Hong Huang Yue-Yi Fang Qing-Sheng Zeng Lai-De Li Le Luo Ying-Si Lai 《PLoS neglected tropical diseases》2022,16(5)
Clonorchiasis is an important food-borne parasitic disease caused by Clonorchis sinensis infection. The evaluation of long-term cost-effectiveness of control strategies is important for disease control and prevention. The present study aimed to assess the cost-effectiveness of the three recommended strategies (i.e., WHO, Chinese and Guangdong strategies) and different combinations of commonly used measures (i.e., preventive chemotherapy, information, education, and communication (IEC) and environmental improvement) on clonorchiasis. The study area, Fusha town in Guangdong Province, was a typical high endemic area in China. The analysis was based on a multi-group transmission model of C. sinensis infection. We set the intervention duration for 10 years and post-intervention period for 50 years. The corresponding costs and DALYs were estimated. Strategies with incremental cost-effectiveness ratios (ICERs) less than 1/5 of the willingness-to-pay threshold were identified as highly cost-effective strategies. The optimal control strategy was obtained using the next best comparator method. The ICERs of Guangdong strategy were $172 (95% CI: $143-$230) US for praziquantel and $106 (95% CI: $85-$143) US for albendazole, suggesting the highest cost-effectiveness among the three recommended strategies. For praziquantel, 470 sets of control strategies were identified as highly cost-effective strategies for achieving infection control (prevalence<5%). The optimal strategy consisted of chemotherapy targeted on at-risk population, IEC and environmental improvement, with coverages all being 100%, and with the ICER of $202 (95% CI: $168-$271) US. The results for transmission control (prevalence<1%) and albendazole were obtained with the same procedures. The findings may help to develop control policies for C. sinensis infection in high endemic areas. Moreover, the method adopted is applicable for assessment of optimal strategies in other endemic areas. 相似文献
102.
Ennian Li Kai Wang Bei Zhang Siqi Guo Senhao Xiao Qi Pan Xiaowan Wang Weiying Chen Yunshan Wu Hesong Xu Xiangqian Kong Cheng Luo Shijie Chen Bo Liu 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1537
The DNA methyltransferases (DNMTs) were found in mammals to maintain DNA methylation. Among them, DNMT1 was the first identified, and it is an attractive target for tumour chemotherapy. DC_05 and DC_517 have been reported in our previous work, which is non-nucleoside DNMT1 inhibitor with low micromolar IC50 values and significant selectivity towards other S-adenosyl-L-methionine (SAM)-dependent protein methyltransferases. In this study, through a process of similarity-based analog searching, a series of DNMT1 inhibitors were designed, synthesized, and evaluated as anticancer agents. SAR studies were conducted based on enzymatic assays. And most of the compounds showed strong inhibitory activity on human DNMT1, especially WK-23 displayed a good inhibitory effect on human DNMT1 with an IC50 value of 5.0 µM. Importantly, the pharmacokinetic (PK) profile of WK-23 was obtained with quite satisfying oral bioavailability and elimination half-life. Taken together, WK-23 is worth developing as DNMT1-selective therapy for the treatment of malignant tumour. 相似文献
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105.
运动性骨骼肌疲劳亚细胞机制的探讨 总被引:7,自引:0,他引:7
本实验采用持续性下坡跑运动,观察大鼠骨骼肌运动后不同时相线粒体形态、代谢、机能等指标的变化,结果表明:大鼠运动后即刻线粒体钙含量、细胞膜丙二醛(MDA)值明显增加,ATP含量和细胞膜Na+,K+-ATP酶活性下降;运动后24h线粒体钙含量、MDA值增加最明显,ATP含量仍未恢复,细胞膜Na+,K+-ATP酶活性基本恢复,线粒体体密度、平均体积比运动前明显增加,比表面缩小;运动后48hATP含量完全恢复,线粒体钙含量、MDA值开始恢复。本研究结果提示,急性运动引起的细胞膜脂质过氧化加强、线粒体形态、代谢机能异常抑制线粒体氧化磷酸化过程、减少ATP生成可能是运动性骨骼肌疲劳的亚细胞机制之一。耐力训练可以通过改善线粒体形态、代谢、机能提高机体的运动能力。 相似文献
106.
氮锌硒肥配合施用对白三叶的固氮作用与氮转移的影响 总被引:6,自引:2,他引:6
在湖北省宜昌县百里荒草场山地黄棕壤上配合施用氮锌硒肥,研究其对混播白三叶,混播黑麦草及单播黑麦草的干重及混播白三叶的固氮作用和氮转移的影响,试验结果表明:(1)氮锌硒肥配合施用,混播黑麦草的干重均高于相应处理的单播黑麦草,混播牧草和单播黑麦草重最高的处理都是N46Zn0Se5,其干重辚25.38 g/盆和19.93g/盆。(2)施氮对混播白三叶,混播黑麦草及单播黑麦草的生长有明显的促进作用,施锌,硒对混播白三叶,混播黑麦草及单播黑麦草的生长作用不明显。(3)混播白三叶氮素的主要来源是固氮作用,占全氮产量的57.6000%-77.258%。(4)混播白三叶固定氮的转移量只占混播黑麦草的全氮产量的0.316%-12.251%,通过正交方差分析发现,适量氮肥(N30mg/kg)促进固定氮的转移,高量氮肥(N46mg/kg)抑制固定氮的转移。 相似文献
107.
微生物蕴藏着大量具有工业应用潜力的生物催化剂。然而,传统培养方法只能从环境中获得不到1%的微生物。宏基因组学是通过提取某一特定环境中的所有微生物基因组DNA、构建基因组文库并对文库进行筛选,寻找和发现新的功能基因的一种方法。它绕过了微生物分离培养过程,成为研究环境样品中不可培养微生物的有力手段。因此,从宏基因组中挖掘新型生物催化剂一直倍受生物学家的关注。以下主要对宏基因组文库的样品来源、DNA提取方法、文库的构建和筛选策略的选择这4个方面的研究状况进行了综述,列举了近年来利用宏基因组技术所获得的新型生物催化剂,并对其今后的研究方向提出了展望。 相似文献
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109.
Lifang Guo Xingchao Geng Li Liu Yufa Miao Zhi Lin Min Yu Yan Fu Lihong Liu Bo Li Yongzhang Luo 《Journal of biochemical and molecular toxicology》2019,33(3)
Endostar, a potent endogenous antiangiogenic factor, is wildly used in clinics. However, it was easily degraded by enzymes and rapidly cleared by the kidneys. To overcome these shortcomings, PEGylated recombinant human endostatin was developed. In this study, the purity of M2ES was evaluated by silver stain and reversed‐phase high‐performance liquid chromatography. Ultraviolet spectrum was used to examine the structural of M2ES and endostar. The bioactivity and antitumor efficacy of M2ES were evaluated using an in vitro endothelial cell migration model and athymic nude mouse xenograft model of a heterogeneous lung adenocarcinoma, respectively. A preclinical study was performed to evaluate the acute toxicity and safety pharmacology in rhesus monkeys. The purity of M2ES was more than 98%; PEG modification has no effect on endostatin structure. Compared with the control group, M2ES dramatically retards endothelial cell migration and tumor growth. After intravenous (IV) infusions of M2ES at a dose level of three and 75 mg/kg in rhesus monkeys, there was no observable serious adverse event in both acute toxicity and safety pharmacology study. On the basis of the quality and bioactivity study data of M2ES and the absence of serious side effect in rhesus monkeys, M2ES was authorized to initiate a phase I clinical trial. 相似文献
110.