Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic potentially affected prenatal care quality and maternal and fetal outcomes globally.What is added by this report?During COV...Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic potentially affected prenatal care quality and maternal and fetal outcomes globally.What is added by this report?During COVID-19 pandemic period,the rates of caesarean sections(CS)and preterm birth for uninfected pregnant women increased slightly in areas that were relatively severely impacted by the pandemic in China.展开更多
Hypoxia is a major characteristic of the tumor microenvironment,and its effects on immune cells are proposed to be important factors for the process of tumor immune escape.It has been reported that hypoxia affects the...Hypoxia is a major characteristic of the tumor microenvironment,and its effects on immune cells are proposed to be important factors for the process of tumor immune escape.It has been reported that hypoxia affects the function of dendritic cells and the antitumor function of T cells.Here we discuss the effects of hypoxia on T-cell survival.Our results showed that hypoxia induced apoptosis of T cells.Adenosine and adenosine receptors(AR)are important to the hypoxia-related signaling pathway.Using AR agonists and antagonists,we demonstrated that hypoxia-induced apoptosis of T cells was mediated by A^(2a)and A^(2b)receptors.Furthermore,we are the first,to our knowledge,to report that hypoxia significantly inhibited the expression of chemokine C receptor 7(CCR7)of T cells via the A^(2)R signal pathway,perhaps representing a mechanism of hypoxia-induced apoptosis of T cells.Collectively,our research demonstrated that hypoxia induces T-cell apoptosis by the A^(2)R signaling pathway partly by suppressing CCR7.Blocking the A^(2)R signaling pathway and/or activation of CCR7 can increase the anti-apoptosis function of T cells and may become a new strategy to improve antitumor potential.展开更多
The COVID-19 outbreak has already become a global pandemic and containing this rapid worldwide transmission is of great challenge.The impacts of temperature and humidity on the COVID-19 transmission rate are still und...The COVID-19 outbreak has already become a global pandemic and containing this rapid worldwide transmission is of great challenge.The impacts of temperature and humidity on the COVID-19 transmission rate are still under discussion.Here,we elucidated these relationships by utilizing two unique scenarios,repeated measurement and natural experiment,using the COVID-19 cases reported from January 23–February 21,2020,in China.The modeling results revealed that higher temperature was most strongly associated with decreased COVID-19 transmission at a lag time of 8 days.Relative humidity(RH)appeared to have only a slight effect.These findings were verified by assessing SARSCoV-2 infectivity under the relevant conditions of temperature(4C–37C)and RH(>40%).We concluded that temperature increase made an important,but not determined,contribution to restrain the COVID19 outbreak in China.It suggests that the emphasis of other effective controlling polices should be strictly implemented to restrain COVID19 transmission in cold seasons.展开更多
基金The Peking University ethics board(No.IRB00001052-20025)The National Key Research and Development Program,P.R.China(Grant No.2020YFC0846300)+1 种基金National Natural Science Foundation of China(Grant No.81673177,41771527)National Health Commission Capacity Building and Continuing Education Center(Grant No.:GWJJ2020100101).
文摘Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic potentially affected prenatal care quality and maternal and fetal outcomes globally.What is added by this report?During COVID-19 pandemic period,the rates of caesarean sections(CS)and preterm birth for uninfected pregnant women increased slightly in areas that were relatively severely impacted by the pandemic in China.
基金This work was supported by grants from the National Natural Science Foundation of China(No.30671902 and No.30872321)the Natural Science Foundation of Shandong Province(No.Y2008C02 and No.Y2006C122).
文摘Hypoxia is a major characteristic of the tumor microenvironment,and its effects on immune cells are proposed to be important factors for the process of tumor immune escape.It has been reported that hypoxia affects the function of dendritic cells and the antitumor function of T cells.Here we discuss the effects of hypoxia on T-cell survival.Our results showed that hypoxia induced apoptosis of T cells.Adenosine and adenosine receptors(AR)are important to the hypoxia-related signaling pathway.Using AR agonists and antagonists,we demonstrated that hypoxia-induced apoptosis of T cells was mediated by A^(2a)and A^(2b)receptors.Furthermore,we are the first,to our knowledge,to report that hypoxia significantly inhibited the expression of chemokine C receptor 7(CCR7)of T cells via the A^(2)R signal pathway,perhaps representing a mechanism of hypoxia-induced apoptosis of T cells.Collectively,our research demonstrated that hypoxia induces T-cell apoptosis by the A^(2)R signaling pathway partly by suppressing CCR7.Blocking the A^(2)R signaling pathway and/or activation of CCR7 can increase the anti-apoptosis function of T cells and may become a new strategy to improve antitumor potential.
基金We would like to express our gratitude for discussions with the researchers from the environmental exposure and human health working group of the China Cohort Consortium(http://chinacohort.bjmu.edu.cn/),as well as special thanks to Dr.Ping Zhong and Dr.Wentao Wang for their instructive guidance.This work was supported by the National Key Research and Development Program,P.R.China(Grant No.2020YFC0846300 and 2020YFC0846200)the National Natural Science Foundation of China(Grant No.41771527,41922057).
文摘The COVID-19 outbreak has already become a global pandemic and containing this rapid worldwide transmission is of great challenge.The impacts of temperature and humidity on the COVID-19 transmission rate are still under discussion.Here,we elucidated these relationships by utilizing two unique scenarios,repeated measurement and natural experiment,using the COVID-19 cases reported from January 23–February 21,2020,in China.The modeling results revealed that higher temperature was most strongly associated with decreased COVID-19 transmission at a lag time of 8 days.Relative humidity(RH)appeared to have only a slight effect.These findings were verified by assessing SARSCoV-2 infectivity under the relevant conditions of temperature(4C–37C)and RH(>40%).We concluded that temperature increase made an important,but not determined,contribution to restrain the COVID19 outbreak in China.It suggests that the emphasis of other effective controlling polices should be strictly implemented to restrain COVID19 transmission in cold seasons.
