The coronavirus disease 2019(COVID-19)pandemic has caused a surge in demand for face masks,with the massive consumption of masks leading to an increase in resource-related and environmental con-cerns.In this work,we f...The coronavirus disease 2019(COVID-19)pandemic has caused a surge in demand for face masks,with the massive consumption of masks leading to an increase in resource-related and environmental con-cerns.In this work,we fabricated meltblown polypropylene(mb-PP)-based high-performance planar face masks and investigated the effects of six commonly used disinfection methods and various mask-wearing periods on the reusability of these masks.The results show that,after three cycles of treatment using hot water at 70℃ for 30 min,which is one of the most scalable,user-friendly methods for viral disinfection,the particle filtration efficiency(PFE)of the mask remained almost unchanged.After mask wearing for 24 h and subsequent disinfection using the same treatment procedures,the PFE decreased to 91.3%;the average number of bacterial and fungal colonies was assessed to be 9.2 and 51.6 colony-forming units per gram(CFU∙g^(-1)),respectively;and coliform and pyogenic bacteria were not detected.Both the PFE and the microbial indicators are well above the standard for reusable masks after disinfection.Schlieren pho-tography was then used to assess the capabilities of used and disinfected masks during use;it showed that the masks exhibit a high performance in suppressing the spread of breathed air.展开更多
This study was designed to explore the regulatory effects of male germ cell secreting factor NODAL on Sertoli cell fate decisions from obstructive azoospermia （OA） and nonobstructive azoospermia （NOA） patients. Hu...This study was designed to explore the regulatory effects of male germ cell secreting factor NODAL on Sertoli cell fate decisions from obstructive azoospermia （OA） and nonobstructive azoospermia （NOA） patients. Human Sertoli cells and male germ cells were isolated using two-step enzymatic digestion and SATPUT from testes of azoospermia patients. Expression of NODAL and its multiple receptors in human Sertoli cells and male germ cells were characterized by reverse transcription-polymerase chain reaction （RT-PCRI and immunochemistry. Human recombinant NODAL and its receptor inhibitor SB431542 were employed to probe their effect on the proliferation of Sertoli cells using the CCK-8 assay. Quantitative PCR and Western blots were utilized to assess the expression of Sertoli cell functional genes and proteins. NODAL was found to be expressed in male germ cells but not in Sertoli cells, whereas its receptors ALK4, ALK7, and ACTR-IIB were detected in Sertoli cells and germ cells, suggesting that NODAL plays a regulatory role in Sertoli cells and germ cells via a paracrine and autocrine pathway, respectively. Human recombinant NODAL could promote the proliferation of human Sertoli cells. The expression of cell cycle regulators, including CYCLIN A, CYCLIN D1 and CYCLIN E, was not remarkably affected by NODAL signaling. NODAL enhanced the expression of essential growth factors, including GDNF, SCF, and BMP4, whereas SB431542 decreased their levels. There was not homogeneity of genes changes by NODAL treatment in Sertoli cells from OA and Sertoli cell-only syndrome （SCO） patients. Collectively, this study demonstrates that NODAL produced by human male germ cells regulates proliferation and numerous gene expression of Sertoli cells.展开更多
基金supported by National Key Research and Development Program of China (2020YFC0844800)the Science and Technology Planning Project of Beijing (Z201100007520006)
文摘The coronavirus disease 2019(COVID-19)pandemic has caused a surge in demand for face masks,with the massive consumption of masks leading to an increase in resource-related and environmental con-cerns.In this work,we fabricated meltblown polypropylene(mb-PP)-based high-performance planar face masks and investigated the effects of six commonly used disinfection methods and various mask-wearing periods on the reusability of these masks.The results show that,after three cycles of treatment using hot water at 70℃ for 30 min,which is one of the most scalable,user-friendly methods for viral disinfection,the particle filtration efficiency(PFE)of the mask remained almost unchanged.After mask wearing for 24 h and subsequent disinfection using the same treatment procedures,the PFE decreased to 91.3%;the average number of bacterial and fungal colonies was assessed to be 9.2 and 51.6 colony-forming units per gram(CFU∙g^(-1)),respectively;and coliform and pyogenic bacteria were not detected.Both the PFE and the microbial indicators are well above the standard for reusable masks after disinfection.Schlieren pho-tography was then used to assess the capabilities of used and disinfected masks during use;it showed that the masks exhibit a high performance in suppressing the spread of breathed air.
文摘This study was designed to explore the regulatory effects of male germ cell secreting factor NODAL on Sertoli cell fate decisions from obstructive azoospermia （OA） and nonobstructive azoospermia （NOA） patients. Human Sertoli cells and male germ cells were isolated using two-step enzymatic digestion and SATPUT from testes of azoospermia patients. Expression of NODAL and its multiple receptors in human Sertoli cells and male germ cells were characterized by reverse transcription-polymerase chain reaction （RT-PCRI and immunochemistry. Human recombinant NODAL and its receptor inhibitor SB431542 were employed to probe their effect on the proliferation of Sertoli cells using the CCK-8 assay. Quantitative PCR and Western blots were utilized to assess the expression of Sertoli cell functional genes and proteins. NODAL was found to be expressed in male germ cells but not in Sertoli cells, whereas its receptors ALK4, ALK7, and ACTR-IIB were detected in Sertoli cells and germ cells, suggesting that NODAL plays a regulatory role in Sertoli cells and germ cells via a paracrine and autocrine pathway, respectively. Human recombinant NODAL could promote the proliferation of human Sertoli cells. The expression of cell cycle regulators, including CYCLIN A, CYCLIN D1 and CYCLIN E, was not remarkably affected by NODAL signaling. NODAL enhanced the expression of essential growth factors, including GDNF, SCF, and BMP4, whereas SB431542 decreased their levels. There was not homogeneity of genes changes by NODAL treatment in Sertoli cells from OA and Sertoli cell-only syndrome （SCO） patients. Collectively, this study demonstrates that NODAL produced by human male germ cells regulates proliferation and numerous gene expression of Sertoli cells.
