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《Vaccine》2022,40(9):1282-1288
ObjectivesPneumococcal infection is a leading cause of morbidity and mortality. We aimed to evaluate the cost-effectiveness of 23-valent polysaccharide vaccine (PPV23) together with influenza vaccination or pneumococcal vaccination alone in adults starting from 50 years vs. 65 years in Hong Kong.MethodsA hypothetical population of 100,000 older adults was included in a Markov model with age ranging from 50 to 85 years to calculate the cost and quality-adjusted life-years (QALYs) gained for vaccination strategies, including: (1) annual influenza vaccine and PPV23 at 50 and 65 years; (2) annual influenza vaccine and PPV23 at 65 years (similar with the current vaccination programme); (3) PPV23 at 50 and 65 years; (4) PPV23 at 65 years; and (5) no vaccination. We evaluated the incremental cost-effectiveness ratio (ICER) and used Monte Carlo simulation for probabilistic sensitivity analysis. The cost-effectiveness threshold was extracted from previous literature.ResultsIn comparison with no vaccination, all strategies were cost-effective with ICERs less than the threshold (US$24,302 per QALY gained). When compared with no vaccination, strategies 1–4 saved US$ 49.5, US$ 94.9, US$ 584.3, and US$ 1114.2 to gain one QALY respectively. In comparison with strategy 2, strategy 1 spent US$ 195.3 to gain one QALY, whilst strategies 3 and 4 showed less effectiveness with increased costs.ConclusionsAll vaccination strategies were cost-effective, among which the strategy of PPV23 at 50/65 years with annual influenza vaccine was cost-effective even in comparison with current vaccination programme. These findings could help inform the design and implementation of vaccination strategies. 相似文献
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目的:研究石菖蒲水提取液及其挥发油对淀粉样β蛋白25-35(Aβ25-35)二级结构的影响及机制。方法:运用圆二色谱表征Aβ25-35二级结构的变化。结果:Aβ25-35孵育不同时间及用石菖蒲水提取液及其挥发油分别干预后, 它的CD图形发生了明显改变。Aβ25-35水溶液孵育30 min全部为α- 螺旋;孵育24h, α-螺旋向着其它的二级结构转化,其中α-螺旋10.10%,β- 折叠18.40%;孵育7 d,主要以β -折叠和不规则卷曲为主,含量分别是27.00%和56.40%。用石菖蒲水提取液及其挥发油分别与Aβ25-35水溶液共同孵育后,α-螺旋结构明显增多,其中以 100%水提取液孵育7 d和100%挥发油孵育7 d的效果最好,α-螺旋含量达到100%。结论:一定浓度石菖蒲水提取液及其挥发油一定时间内能够有效地阻止了Aβ25-35由α- 螺旋向β -折叠转化。 相似文献
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Huimin Cheng Liangbing Fu Xia Yang Yujian Yang Zhening Zhang Yuan Tao Junting Wan Zhengchao Tu Jianxin Chen Yingjun Li 《Journal of medical virology》2023,95(1):e28327
Quinolin-2-one represents an important and valuable chemical motif that possesses a wide variety of biological activities; however, the anti-influenza activities of quinolin-2-one-containing compounds were rarely reported. Herein, we describe the screening and identification of 3-aryl-quinolin-2-one derivatives as a novel class of antiviral agents. The 3-aryl-quinolinone derivatives were synthesized via an efficient copper-catalyzed reaction cascade that we previously developed. Using this synthetic method, preliminary structure–activity relationships of this scaffold against the influenza A virus infection were systematically explored. The most potent compound 34 displayed IC50 values of 2.14 and 4.88 μM against the replication of H3N2 (A/HK/8/68) and H1N1 (A/WSN/33) strains, respectively, without apparent cytotoxicity on MDCK cells. We further demonstrated that 27 and 34 potently inhibited the plaque formation of the IAV, rendering this scaffold attractive for pursuing novel anti-influenza agents. 相似文献