Graphical abstractDipyridamole bound to the SARS-CoV-2 protease Mpro after identified via the virtual screening and bioassay validation, and thus suppressed viral replication in vitro. As a result, dipyridamole supplementation was associated with significantly decreased concentrations of D-dimers, increased lymphocyte and platelet recovery in the circulation, and markedly improved clinical outcomes in comparison to the control patients.Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can cause acute respiratory distress syndrome, hypercoagulability, hypertension, and multiorgan dysfunction.Effective antivirals with safe clinical profile are urgently needed to improve the overall prognosis. In an analysis of a randomly collected cohort of 124 patients with Corona Virus Disease 2019 , we found that hypercoagulability as indicated by elevated concentrations of D-dimers was associated with disease severity. By virtual screening of a U.S. Food and Drug Administration (FDA) approved drug library, we identified an anticoagulation agent dipyridamole (DIP) in silico, which suppressed SARS-CoV-2 replication in vitro. In a proof-of-concept trial involving 31 patients with COVID-19, DIP supplementation was associated with significantly decreased concentrations of D-dimers (P<0.05), increased lymphocyte and platelet recovery in the circulation, and markedly improved clinical outcomes in comparison to the control patients. In particular, all 8 of the DIP-treated severely ill patients showed remarkable improvement: 7 patients (87.5%) achieved clinical cure and were discharged from the hospitals while the remaining 1 patient (12.5%) was in clinical remission.

By learning the PM 2.5 readings and meteorological records from 2010–2015, the severity of PM 2.5 pollution in Beijing is quantified with a set of statistical measures. As PM 2.5 concentration is highly influenced by meteorological conditions, we propose a statistical approach to adjust PM 2.5 concentration with respect to meteorological conditions, which can be used to monitor PM 2.5 pollution in a location. The adjusted monthly averages and percentiles are employed to test if the PM 2.5 levels in Beijing have been lowered since China's State Council set up a pollution reduction target. The results of the testing reveal significant increases, rather than decreases, in the PM 2.5 concentrations in the years 2013 and 2014 as compared with those in year 2012. We conduct analyses on two quasi-experiments—the Asia-Pacific Economic Cooperation meeting in November 2014 and the annual winter heating—to gain insight into the impacts of emissions on PM 2.5 . The analyses lead to a conclusion that a fundamental shift from mainly coal-based energy consumption to much greener alternatives in Beijing and the surrounding North China Plain is the key to solving the PM 2.5 problem in Beijing.

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In recent years, accumulating evidence has supported the hypothesis that lower vitamin D status is associated with several known risk factors of stroke. However, the relationship between vitamin D and stroke is still uncertain. To explore if there was an association between vitamin D status and the risk of stroke, a systematic review and a meta-analysis were conducted by searching three databases: Pubmed, Embase, and the Cochrane Library. Following the application of inclusion and exclusion criteria, the relative risk estimates of all the included studies were pooled together to compare the risk of stroke between the lowest and the highest category of vitamin D. The Newcastle–Ottawa Scale (NOS) and the Cochrane Risk of Bias Tool were used to assess the risk of bias, and the publication bias was detected by using a funnel plot and Egger’s test. Nineteen studies were included and the pooled relative risk was 1.62 (95% CI: 1.34–1.96). Further analysis found that vitamin D status was associated with ischemic stroke (relative risk = 2.45, 95% CI: 1.56–3.86), but not with hemorrhagic stroke (relative risk = 2.50, 95% CI: 0.87–7.15). In conclusion, our meta-analysis supported the hypothesis that lower vitamin D status was associated with an increased risk of ischemic stroke. Further studies are required to confirm this association and to explore the association among different subtypes.

We investigate particulate matter (PM2.5) data reliability in five major Chinese cities: Beijing, Shanghai, Guangzhou, Chengdu, and Shenyang by cross‐validating data from the U.S. diplomatic posts and the nearby Ministry of Environmental Protection sites based on 3 years' data from January 2013. The investigation focuses on the consistency in air quality assessment derived from the two data sources. It consists of studying (i) the occurrence length and percentage of different PM2.5 concentration ranges; (ii) the air quality assessment for each city; and (iii) the winter‐heating effects in Beijing and Shenyang. Our analysis indicates that the two data sources produced highly consistent air quality assessment in the five cities. This is encouraging as it would inject a much needed confidence on the air pollution measurements from China. We also provide air quality assessments on the severity and trends of the fine particulate matter pollution in the five cities. The assessments are produced by statistically constructing the standard monthly meteorological conditions for each city, which are designed to minimize the effects of confounding factors due to yearly variations of some important meteorological variables. Our studies show that Beijing and Chengdu had the worst air quality, while Guangzhou and Shanghai faired the best among the five cities. Most of the five cities had their PM2.5 concentration decreased significantly in the last 2 years. By linking the air quality with the amount of energy consumed, our study suggests that the geographical configuration is a significant factor in a city's air quality management and economic development.