The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive positi...The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases significantly.Notably, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.展开更多
Due to increasing morbidity worldwide,fractures are becoming an emerging public health concern.This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures.Type H ...Due to increasing morbidity worldwide,fractures are becoming an emerging public health concern.This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures.Type H vessels have recently been identified as a bone-specific vascular subtype that supports osteogenesis.Here,we show that metformin accelerated fracture healing in both osteoporotic and normal mice.Moreover,metformin promoted angiogenesis in vitro under hypoxia as well as type H vessel formation throughout fracture healing.Mechanistically,metformin increased the expression of HIF-1α,an important positive regulator of type H vessel formation,by inhibiting the expression of YAP1/TAZ in calluses and hypoxia-cultured human microvascular endothelial cells(HMECs).The results of HIF-1αor YAP1/TAZ interference in hypoxia-cultured HMECs using si RNA further suggested that the enhancement of HIF-1αand its target genes by metformin is primarily through YAP1/TAZ inhibition.Finally,overexpression of YAP1/TAZ partially counteracted the effect of metformin in promoting type H vessel-induced angiogenesis-osteogenesis coupling during fracture repair.In summary,our findings suggest that metformin has the potential to be a therapeutic agent for fractures by promoting type H vessel formation through YAP1/TAZ inhibition.展开更多
Osteoporosis is a debilitating bone disease affecting millions of people. Here, we used human urine-derived stem cells(USCs),which were noninvasively harvested from unlimited and easily available urine, as a "fac...Osteoporosis is a debilitating bone disease affecting millions of people. Here, we used human urine-derived stem cells(USCs),which were noninvasively harvested from unlimited and easily available urine, as a "factory" to obtain extracellular vesicles(USCEVs) and demonstrated that the systemic injection of USC-EVs effectively alleviates bone loss and maintains bone strength in osteoporotic mice by enhancing osteoblastic bone formation and suppressing osteoclastic bone resorption. More importantly, the anti-osteoporotic properties of USC-EVs are not notably disrupted by the age, gender, or health condition(with or without osteoporosis) of the USC donor. Mechanistic studies determined that collagen triple-helix repeat containing 1(CTHRC1) and osteoprotegerin(OPG) proteins are enriched in USC-EVs and required for USC-EV-induced pro-osteogenic and anti-osteoclastic effects. Our results suggest that autologous USC-EVs represent a promising novel therapeutic agent for osteoporosis by promoting osteogenesis and inhibiting osteoclastogenesis by transferring CTHRC1 and OPG.展开更多
BACKGROUND Metabolic reprogramming has been identified as a core hallmark of cancer.Solute carrier family 2 is a major glucose carrier family.It consists of 14 members,and we mainly study solute carrier family 2 membe...BACKGROUND Metabolic reprogramming has been identified as a core hallmark of cancer.Solute carrier family 2 is a major glucose carrier family.It consists of 14 members,and we mainly study solute carrier family 2 member 1(SLC2A1)and solute carrier family 2 member 2(SLC2A2)here.SLC2A1,mainly existing in human erythrocytes,brain endothelial cells,and normal placenta,was found to be increased in hepatocellular carcinoma(HCC),while SLC2A2,the major transporter of the normal liver,was decreased in HCC.AIM To identify if SLC2A1 and SLC2A2 were associated with immune infiltration in addition to participating in the metabolic reprogramming in HCC.METHODS The expression levels of SLC2A1 and SLC2A2 were tested in HepG2 cells,HepG215 cells,and multiple databases.The clinical characteristics and survival data of SLC2A1 and SLC2A2 were examined by multiple databases.The correlation between SLC2A1 and SLC2A2 was analyzed by multiple databases.The functions and pathways in which SLC2A1,SLC2A2,and frequently altered neighbor genes were involved were discussed in String.Immune infiltration levels and immune marker genes associated with SLC2A1 and SLC2A2 were discussed from multiple databases.RESULTS The expression level of SLC2A1 was up-regulated,but the expression level of SLC2A2 was down-regulated in HepG2 cells,HepG215 cells,and liver cancer patients.The expression levels of SLC2A1 and SLC2A2 were related to tumor volume,grade,and stage in HCC.Interestingly,the expression levels of SLC2A1 and SLC2A2 were negatively correlated.Further,high SLC2A1 expression and low SLC2A2 expression were linked to poor overall survival and relapse-free survival.SLC2A1,SLC2A2,and frequently altered neighbor genes played a major role in the occurrence and development of tumors.Notably,SLC2A1 was positively correlated with tumor immune infiltration,while SLC2A2 was negatively correlated with tumor immune infiltration.Particularly,SLC2A2 methylation was positively correlated with lymphocytes.CONCLUSION SLC2A1 and SLC2A2 are independent therapeutic targets for HCC,and they are quintessential marker molecules for predicting and regulating the number and status of immune cells in HCC.展开更多
Objective:A cell model of cardiac fibroblasts proliferation induced by aldosterone was established to observe the effect of aldosterone on the proliferation of rat cardiac fibroblasts.Methods:Primary cardiac fibroblas...Objective:A cell model of cardiac fibroblasts proliferation induced by aldosterone was established to observe the effect of aldosterone on the proliferation of rat cardiac fibroblasts.Methods:Primary cardiac fibroblasts were cultured by trypsin digestion method and differential adhesion method,primary cardiac fibroblasts were sub-cultured by conventional digestion method,and the immunocytochemical assay was used to identify cardiac fibroblasts.The second-generation cardiac fibroblasts were randomly divided into five groups:standard control group,10-9 mol/L aldosterone(ALD1)group,10-8 mol/L aldosterone(ALD2)group,10-7 mol/L aldosterone(ALD3)group,and 10-6 mol/L aldosterone(ALD4)group.The viability of fibroblast cells in each group was detected by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Results:Vimentin staining assay showed that the cultured cells staining positive,and the purity of cultured mouse cardiac fibroblasts was 95%.The results of methyl thiazolyl tetrazolium showed that compared with the control group,the low concentration of aldosterone(10-9 mol/L)had no significant effect on the proliferation of normal cardiac fibroblasts.With the increase in the intensity of(10-8–10-6)mol/L,aldosterone could significantly promote the proliferation of cardiac fibroblasts.Moreover,there was no significant difference in absorbance value between the aldosterone group(10-6 mol/L)and the aldosterone group(10-7 mol/L)(P>0.05).The highest concentration of aldosterone group 10-7 mol/L promoted the proliferation of cardiac the optimum concentration was 10-7 mol/L.Conclusion:Aldosterone can promote the spread of cardiac fibroblasts in a specific concentration range.展开更多
Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,...Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,we report a novel batorigin CoV causing severe and fatal pneumonia in humans.Methods:We collected clinical data and bronchoalveolar lavage(BAL)specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital,Hubei province,China.Nucleic acids of the BAL were extracted and subjected to next-generation sequencing.Virus isolation was carried out,and maximum-likelihood phylogenetic trees were constructed.Results:Five patients hospitalized from December 18 to December 29,2019 presented with fever,cough,and dyspnea accompanied by complications of acute respiratory distress syndrome.Chest radiography revealed diffuse opacities and consolidation.One of these patients died.Sequence results revealed the presence of a previously unknownβ-CoV strain in all five patients,with 99.8%to 99.9%nucleotide identities among the isolates.These isolates showed 79.0%nucleotide identity with the sequence of SARS-CoV(GenBank NC_004718)and 51.8%identity with the sequence of MERS-CoV(GenBank NC_019843).The virus is phylogenetically closest to a bat SARS-like CoV(SL-ZC45,GenBank MG772933)with 87.6%to 87.7%nucleotide identity,but is in a separate clade.Moreover,these viruses have a single intact open reading frame gene 8,as a further indicator of bat-origin CoVs.However,the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV,indicating that these viruses might use the same receptor.Conclusion:A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.展开更多
Nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite was prepared by chemical co-precipitation method.The samples were characterized by X-ray diffraction(XRD),field-emission transmission electron microscopy(FETEM),vibrating ...Nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite was prepared by chemical co-precipitation method.The samples were characterized by X-ray diffraction(XRD),field-emission transmission electron microscopy(FETEM),vibrating sample magnetometer(VSM)and network analyzer.TEM analysis indicates that the diameter of as-prepared powder is about 20-30 nm.The saturation magnetization of nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite is 74.01 mA·m^(2)·g^(−1).The complex permittivity and complex permeability of the Co-Zn ferrite were measured by vector network analyzer in the frequency range of 2.0-18.0 GHz,and the reflection loss(RL)was investigated according to the wave transmission theory.The results show that the maximum reflection loss reaches−13.7 dB at 6.8 GHz and the bandwidth of reflection loss less than−10 dB reaches 3.8 GHz.The as-prepared nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite can be potentially used as an excellent microwave absorber in the C-band.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.61574171,61704127,11875229,51872251,and 12027813)。
文摘The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases significantly.Notably, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.
基金supported by the National Natural Science Foundation of China (Grant Nos.81874006,82172399,81902222,82060395,81902277,82072504,82000845)the Hunan Province Natural Science Foundation of China (Grant Nos.2020JJ4928,2020JJ4897,2021JJ30038,2021JJ40492)the Independent Exploration and Innovation Project of Central South University (Grant Nos.2020zzts255)。
文摘Due to increasing morbidity worldwide,fractures are becoming an emerging public health concern.This study aimed to investigate the effect of metformin on the healing of osteoporotic as well as normal fractures.Type H vessels have recently been identified as a bone-specific vascular subtype that supports osteogenesis.Here,we show that metformin accelerated fracture healing in both osteoporotic and normal mice.Moreover,metformin promoted angiogenesis in vitro under hypoxia as well as type H vessel formation throughout fracture healing.Mechanistically,metformin increased the expression of HIF-1α,an important positive regulator of type H vessel formation,by inhibiting the expression of YAP1/TAZ in calluses and hypoxia-cultured human microvascular endothelial cells(HMECs).The results of HIF-1αor YAP1/TAZ interference in hypoxia-cultured HMECs using si RNA further suggested that the enhancement of HIF-1αand its target genes by metformin is primarily through YAP1/TAZ inhibition.Finally,overexpression of YAP1/TAZ partially counteracted the effect of metformin in promoting type H vessel-induced angiogenesis-osteogenesis coupling during fracture repair.In summary,our findings suggest that metformin has the potential to be a therapeutic agent for fractures by promoting type H vessel formation through YAP1/TAZ inhibition.
基金supported by the National Natural Science Foundation of China (Grant nos. 81522012, 81702237, 81670807, 81871822, 81801395, 81600699, 81701383, and 81802138)the Thousand Youth Talents Plan of China (Grant no. D1119003)+8 种基金the Medicine and Health Science and Technology Innovation Project of Chinese Academy of Medical Sciences (Grant no. 2018-I2M-HL-024)the High Level Talent Gathering Project of Hunan Province (Grant nos. 2017XK2039, and 2018RS3029)the Innovation Driven Project of Central South University (Grant nos. 2016CX028,2019CX014, and 2018CX029)the Youth Foundation of Xiangya Hospital in Central South University (Grant no. 2016Q10)the Hunan Provincial Innovation Foundation for Postgraduate (Grant no. CX2018B045)the Fundamental Research Funds for the Central Universities of Central South University (Grant nos. 2017zzts211 and 2018zzts895)the Hunan Province Natural Science Foundation of China (Grant no. 2017JJ3501)the China Postdoctoral Science Foundation (Grant nos. 2017M612596, 2017M622614, and 2018M632998)the Natural Science Foundation for Distinguished Yong Scholars of Guangdong Province (Grant no. 2016A030306051)
文摘Osteoporosis is a debilitating bone disease affecting millions of people. Here, we used human urine-derived stem cells(USCs),which were noninvasively harvested from unlimited and easily available urine, as a "factory" to obtain extracellular vesicles(USCEVs) and demonstrated that the systemic injection of USC-EVs effectively alleviates bone loss and maintains bone strength in osteoporotic mice by enhancing osteoblastic bone formation and suppressing osteoclastic bone resorption. More importantly, the anti-osteoporotic properties of USC-EVs are not notably disrupted by the age, gender, or health condition(with or without osteoporosis) of the USC donor. Mechanistic studies determined that collagen triple-helix repeat containing 1(CTHRC1) and osteoprotegerin(OPG) proteins are enriched in USC-EVs and required for USC-EV-induced pro-osteogenic and anti-osteoclastic effects. Our results suggest that autologous USC-EVs represent a promising novel therapeutic agent for osteoporosis by promoting osteogenesis and inhibiting osteoclastogenesis by transferring CTHRC1 and OPG.
基金Supported by National Natural Science Foundation of China,No.81873112Natural Science Foundation of Hebei Province,No.H2020423009+2 种基金Hundred Outstanding Innovative Talents Support Program of Universities in Hebei Province,No.SLRC2019043Basic Scientific Research Project of Hebei Provincial Colleges and Universities,No.JTZ2020005Scientific and Technological Capability Improvement Project of the Hebei University of Chinese Medicine,No.KTZ2019002.
文摘BACKGROUND Metabolic reprogramming has been identified as a core hallmark of cancer.Solute carrier family 2 is a major glucose carrier family.It consists of 14 members,and we mainly study solute carrier family 2 member 1(SLC2A1)and solute carrier family 2 member 2(SLC2A2)here.SLC2A1,mainly existing in human erythrocytes,brain endothelial cells,and normal placenta,was found to be increased in hepatocellular carcinoma(HCC),while SLC2A2,the major transporter of the normal liver,was decreased in HCC.AIM To identify if SLC2A1 and SLC2A2 were associated with immune infiltration in addition to participating in the metabolic reprogramming in HCC.METHODS The expression levels of SLC2A1 and SLC2A2 were tested in HepG2 cells,HepG215 cells,and multiple databases.The clinical characteristics and survival data of SLC2A1 and SLC2A2 were examined by multiple databases.The correlation between SLC2A1 and SLC2A2 was analyzed by multiple databases.The functions and pathways in which SLC2A1,SLC2A2,and frequently altered neighbor genes were involved were discussed in String.Immune infiltration levels and immune marker genes associated with SLC2A1 and SLC2A2 were discussed from multiple databases.RESULTS The expression level of SLC2A1 was up-regulated,but the expression level of SLC2A2 was down-regulated in HepG2 cells,HepG215 cells,and liver cancer patients.The expression levels of SLC2A1 and SLC2A2 were related to tumor volume,grade,and stage in HCC.Interestingly,the expression levels of SLC2A1 and SLC2A2 were negatively correlated.Further,high SLC2A1 expression and low SLC2A2 expression were linked to poor overall survival and relapse-free survival.SLC2A1,SLC2A2,and frequently altered neighbor genes played a major role in the occurrence and development of tumors.Notably,SLC2A1 was positively correlated with tumor immune infiltration,while SLC2A2 was negatively correlated with tumor immune infiltration.Particularly,SLC2A2 methylation was positively correlated with lymphocytes.CONCLUSION SLC2A1 and SLC2A2 are independent therapeutic targets for HCC,and they are quintessential marker molecules for predicting and regulating the number and status of immune cells in HCC.
基金This study was supported by the project of Hebei Provincial Administration of traditional Chinese Medicine(No.2018161)the Hebei Health and Family Planning Commission(No.20170875)the Scientific Research Project of College students in Chengde Medical College(No.2019033).
文摘Objective:A cell model of cardiac fibroblasts proliferation induced by aldosterone was established to observe the effect of aldosterone on the proliferation of rat cardiac fibroblasts.Methods:Primary cardiac fibroblasts were cultured by trypsin digestion method and differential adhesion method,primary cardiac fibroblasts were sub-cultured by conventional digestion method,and the immunocytochemical assay was used to identify cardiac fibroblasts.The second-generation cardiac fibroblasts were randomly divided into five groups:standard control group,10-9 mol/L aldosterone(ALD1)group,10-8 mol/L aldosterone(ALD2)group,10-7 mol/L aldosterone(ALD3)group,and 10-6 mol/L aldosterone(ALD4)group.The viability of fibroblast cells in each group was detected by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Results:Vimentin staining assay showed that the cultured cells staining positive,and the purity of cultured mouse cardiac fibroblasts was 95%.The results of methyl thiazolyl tetrazolium showed that compared with the control group,the low concentration of aldosterone(10-9 mol/L)had no significant effect on the proliferation of normal cardiac fibroblasts.With the increase in the intensity of(10-8–10-6)mol/L,aldosterone could significantly promote the proliferation of cardiac fibroblasts.Moreover,there was no significant difference in absorbance value between the aldosterone group(10-6 mol/L)and the aldosterone group(10-7 mol/L)(P>0.05).The highest concentration of aldosterone group 10-7 mol/L promoted the proliferation of cardiac the optimum concentration was 10-7 mol/L.Conclusion:Aldosterone can promote the spread of cardiac fibroblasts in a specific concentration range.
基金This study was supported by grants from the Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(No.2016-I2M-1-014)the National Major Science&Technology Project for Control and Prevention of Major Infectious Diseases in China(Nos.2017ZX10103004,2018ZX10305409,2017ZX10204401)the National Natural Science Foundation(No.81930063)
文摘Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,we report a novel batorigin CoV causing severe and fatal pneumonia in humans.Methods:We collected clinical data and bronchoalveolar lavage(BAL)specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital,Hubei province,China.Nucleic acids of the BAL were extracted and subjected to next-generation sequencing.Virus isolation was carried out,and maximum-likelihood phylogenetic trees were constructed.Results:Five patients hospitalized from December 18 to December 29,2019 presented with fever,cough,and dyspnea accompanied by complications of acute respiratory distress syndrome.Chest radiography revealed diffuse opacities and consolidation.One of these patients died.Sequence results revealed the presence of a previously unknownβ-CoV strain in all five patients,with 99.8%to 99.9%nucleotide identities among the isolates.These isolates showed 79.0%nucleotide identity with the sequence of SARS-CoV(GenBank NC_004718)and 51.8%identity with the sequence of MERS-CoV(GenBank NC_019843).The virus is phylogenetically closest to a bat SARS-like CoV(SL-ZC45,GenBank MG772933)with 87.6%to 87.7%nucleotide identity,but is in a separate clade.Moreover,these viruses have a single intact open reading frame gene 8,as a further indicator of bat-origin CoVs.However,the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV,indicating that these viruses might use the same receptor.Conclusion:A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.
基金financially supported by the National Natural Science Foundation of China(Nos.51402154,51202111)the Natural Science Foundation of Jiangsu Province(No.BK20141000)+1 种基金the Natural Science Foundation of Jiangsu Provincial Universities(No.14KJB430019)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite was prepared by chemical co-precipitation method.The samples were characterized by X-ray diffraction(XRD),field-emission transmission electron microscopy(FETEM),vibrating sample magnetometer(VSM)and network analyzer.TEM analysis indicates that the diameter of as-prepared powder is about 20-30 nm.The saturation magnetization of nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite is 74.01 mA·m^(2)·g^(−1).The complex permittivity and complex permeability of the Co-Zn ferrite were measured by vector network analyzer in the frequency range of 2.0-18.0 GHz,and the reflection loss(RL)was investigated according to the wave transmission theory.The results show that the maximum reflection loss reaches−13.7 dB at 6.8 GHz and the bandwidth of reflection loss less than−10 dB reaches 3.8 GHz.The as-prepared nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite can be potentially used as an excellent microwave absorber in the C-band.
