BACKGROUND Characteristics of alterations of serum hepatitis B virus(HBV) RNA in different chronic hepatitis B(CHB) patients still cannot be fully explained. Whether HBV RNA can predict HBeAg seroconversion is still c...BACKGROUND Characteristics of alterations of serum hepatitis B virus(HBV) RNA in different chronic hepatitis B(CHB) patients still cannot be fully explained. Whether HBV RNA can predict HBeAg seroconversion is still controversial.AIM To investigate whether HBV RNA can predict virological response or HBeAg seroconversion during entecavir(ETV) treatment when HBV DNA is undetectable.METHODS The present study evaluated 61 individuals who were diagnosed and treated with long-term ETV monotherapy at the Department of Infectious Diseases of Peking University First Hospital(China) from September 2006 to December 2007.Finally, 30 treatment-naive individuals were included. Serum HBV RNA were extracted from 140 μL serum samples at two time points. Then they were reverse transcribed to cDNA with the HBV-specific primer. The product was quantified by real-time quantitative PCR(RT-PCR) using TAMARA probes. Statistical analyses were performed with IBM SPSS 20.0.RESULTS Level of serum HBV RNA at baseline was 4.15 ± 0.90 log10 copies/mL. HBV RNA levels showed no significant difference between the virological response(VR)and partial VR(PVR) groups at baseline(P = 0.940). Serum HBV RNA significantly decreased among patients who achieved a VR during ETV therapy(P < 0.001). The levels of HBV RNA in both HBeAg-positive patients with seroconversion group and those with no seroconversion increased after 24 wk of treatment. Overall, HBV RNA significantly but mildly correlated to HBsAg(r =0.265, P = 0.041), and HBV RNA was not correlated to HBV DNA(r = 0.242, P =0.062). Furthermore, serum HBV RNA was an independent indicator for predicting HBeAg seroconversion and virological response. HBeAg seroconversion was more likely in CHB patients with HBV RNA levels below4.12 log10 copies/mL before treatment.CONLUSION The level of serum HBV RNA could predict HBeAg seroconversion and PVR during treatment. In the PVR group, the level of serum HBV RNA tends to be increasing.展开更多
AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T a...AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T and G1764A) mutant viruses and serum levels of hepatitis B virus(HBV) DNA, hepatitis B surface antigen(HBs Ag), and HB core-related antigen were analyzed in chronic hepatitis B patients before and after HBe Ag seroconversion(n = 25), in those who were persistently HBe Ag positive(n = 18), and in those who were persistently anti-HBe positive(n = 43). All patients were infected with HBV genotype C and were followed for a median of 9 years.RESULTS: Although the pre-core mutant became predominant(24% to 65%, P = 0.022) in the HBe Ag seroconversion group during follow-up, the proportion of the basal core promoter mutation did not change. Median HBV viral markers were significantly higher in patients without the mutations in an HBe Ag positive status(HBV DNA: P = 0.003; HBs Ag: P < 0.001; HB core-related antigen: P = 0.001). In contrast, HBV DNA(P = 0.012) and HBs Ag(P = 0.041) levels were significantly higher in patients with the pre-core mutation in an anti-HBe positive status.CONCLUSION: There is an opposite association of the pre-core mutation with viral load before and after HBe Ag seroconversion in patients with HBV infection.展开更多
Reactivation of hepatitis B virus(HBV)can occur in lymphoma patients infected with HBV when they receive chemotherapy or immunotherapy.Prophylactic administration of lamivudine(LAM)reduces the morbidity and mortality ...Reactivation of hepatitis B virus(HBV)can occur in lymphoma patients infected with HBV when they receive chemotherapy or immunotherapy.Prophylactic administration of lamivudine(LAM)reduces the morbidity and mortality associated with HBV reactivation.However,what defines HBV reactivation and the optimal duration of treatment with LAM have not yet been clearly established.HBV reactivation may occur due to the cessation of prophylactic LAM,although re-treatment with nucleoside analogs may sometimes result in hepatitis B surface antigen(HBsAg)seroconversion,which is a satisfactory endpoint for the management of HBV infection.We report a case of HBV reactivation in a 68-year-old HBsAg-positive patient who received rituximab-based immunochemotherapy for follicular lymphoma.HBV reactivation developed following cessation of prophylactic LAM therapy.The patient subsequently received treatment with entecavir(ETV),which led to a rapid and sustained suppression of HBV replication and HBsAg seroconversion.We also appraised the literature concerning HBV reactivation and the role of ETV in the management of HBV reactivation in lymphoma patients.A total of 28 cases of HBV reactivation have been reported as having been treated with ETV during or after immunosuppressive chemotherapy in lymphoma patients.We conclude that ETV is an efficacious and safe treatment for HBV reactivation following LAM cessation in lymphoma patients treated with rituximab-based immunochemotherapy.展开更多
BACKGROUND Quantitative hepatitis B core-related antigen(qHBcrAg)has a better correlation with intrahepatic hepatitis B virus(HBV)covalently closed circular DNA(cccDNA)than HBV DNA or hepatitis B e antigen(HBeAg),but ...BACKGROUND Quantitative hepatitis B core-related antigen(qHBcrAg)has a better correlation with intrahepatic hepatitis B virus(HBV)covalently closed circular DNA(cccDNA)than HBV DNA or hepatitis B e antigen(HBeAg),but data are still lacking for its clinical application.AIM The aim was to investigate serum qHBcrAg levels in patients with chronic hepatitis B and assess the correlation of serum qHBcrAg with pregenomic RNA(pgRNA),cccDNA,and HBeAg seroconversion.METHODS This study was a secondary analysis of patients who underwent percutaneous liver biopsy between July 2014 and June 2019 in two multicenter randomized controlled clinical trials of peginterferon vs nucleos(t)ide analog(NUC)-based therapy(NCT03509688 and NCT03546530).Serum qHBcrAg,pgRNA,HBV DNA,hepatitis B core antigen,HBeAg,liver cccDNA,and HBV DNA were measured.The correlations of serum qHBcrAg with other biomarkers were analyzed.RESULTS A total of 139 patients were included.The mean qHBcrAg levels were 5.32±1.18 log10 U/mL at baseline and decreased during treatment(all P<0.0001).Serum qHBcrAg levels were positively correlated with pgRNA(r=0.597,P<0.0001)and cccDNA(r=0.527,P<0.0001)levels.The correlation of serum qHBcrAg level and intrahepatic HBV DNA levels at baseline was weak but significant(r=0.399,P<0.0001).HBcrAg predicted HBeAg seroconversion,with areas under the receiver operating characteristics curve of 0.788 at 24 wk and 0.825 at 48 wk.Log HBcrAg at wk 24 and 48 was independently associated with HBeAg seroconversion[odds ratio(OR)=2.402,95%confidence interval(CI):1.314-4.391,P=0.004;OR=3.587,95%CI:1.315-9.784,P=0.013].CONCLUSION Serum HBcrAg levels were correlated with HBV virological markers and could be used to predict HBeAg seroconversion.展开更多
Objective To investigate the efficiency of pegylated interferon α therapy for patients with HBe Ag-positive chronic hepatitis B(CHB) and explore whether liver histopathological features and other factors might influe...Objective To investigate the efficiency of pegylated interferon α therapy for patients with HBe Ag-positive chronic hepatitis B(CHB) and explore whether liver histopathological features and other factors might influence HBe Ag seroconversion.Methods Total of 80 HBe Ag-positive CHB patients who received liver puncture were treated with pegylated interferon α once a week for 48 weeks. The rate of HBe Ag seroconversion was determined after therapy, and the factors influencing HBe Ag seroconversion were analyzed.Results The rate of HBe Ag seroconversion was 30.00% at the end of treatment. The rate of HBe Ag seroconversion gradually increased with the elevation of liver inflammatory activity(χ2 = 9.170, P = 0.027). But liver fibrosis has little correlation with the rate of HBeA g seroconversion(χ2 = 5.917, P = 0.116). Except HBeA g, other baseline indexes including gender, age, serum ALT and serum HBV DNA 1evels had no statistical difference between the patients with HBe Ag seroconversion and the patients without HBe Ag seroconversion. By binary logistic regression analysis, liver inflammation and HBeA g were influencing factors for HBeA g seroconversion. Conclusions Pegylated interferon α therapy induces a higher rate of HBeA g seroconversion in HBeA g-positive chronic hepatitis B patients with severe liver inflammation, so the liver biopsies should be performed in time.展开更多
<strong>Introduction: </strong>The risk of transmission of pathogens such as hepatitis B virus threatens the safety of transfused patients especially in high endemic areas. The aim of this study was to det...<strong>Introduction: </strong>The risk of transmission of pathogens such as hepatitis B virus threatens the safety of transfused patients especially in high endemic areas. The aim of this study was to determine the incidence and factors associated with hepatitis B virus surface antigen (HBsAg) seroconversion in blood donors at the Regional Blood Transfusion Centre of Ouagadougou. <strong>Methods:</strong> A retrospective cohort study of voluntary non-remunerated blood donors (VNRBD), was conducted from 2008 to 2017. Data on HBsAg seroconversion were collected. The Kaplan-Meier method and the Log-Rank test were used to estimate the survival curves. Cox’s regression identified the factors associated with this seroconversion. <strong>Results:</strong> Of 23,494 donors, 559 had HBsAg seroconversion. The number of donor years was 58,637.50 and the HBV incidence rate was 9.53 per 1000 donor years. The median seroconversion time was 75.73 months with extremes of 2.7 months and 107.12 months. The risk of seroconversion was 1.30 times higher among donors aged 21 to 24 years old (p = 0.007) and 2.49 times higher among those over 24 years old (p < 0.0001) than among donors under 21 years old. Female donors were 1.11 times more likely to seroconvert than male donors (p = 0.33). Donor residence was not significantly associated with HBsAg seroconversion (Hazard ratio = 1.12;p = 0.36). The risk of seroconversion decreased significantly with the number of blood donations (Hazard ratio = 0.58;p = 0.006). <strong>Conclusion: </strong>The incidence of HBsAg remains high among blood donors, which could have a negative impact on transfusion safety. The age of the blood donor was significantly associated to AgHBs seroconversion.展开更多
The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of...The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of the electronic structure from single-atom doping to heteroatom codoping in CAs has not yet been thoroughly investigated,and the impact of codoping on potassium ion(K+)storage and diffusion pathways as electrode material remains unclear.In this study,experimental and theoretical simulations were conducted to demonstrate that heteroatom codoping,composed of multiple heteroatoms(O/N/B)with different properties,has the potential to improve the electrical properties and stability of CAs compared to single-atom doping.Electronic states near the Fermi level have revealed that doping with O/N/B generates a greater number of active centers on adjacent carbon atoms than doping with O and O/N atoms.As a result of synergy with enhanced wetting ability(contact angle of 9.26°)derived from amino groups and hierarchical porous structure,ON-CA has the most optimized adsorption capacity(−1.62 eV)and diffusion barrier(0.12 eV)of K^(+).The optimal pathway of K^(+)in ON-CA is along the carbon ring with N or O doping.As K^(+)storage material for supercapacitors and ion batteries,it shows an outstanding specific capacity and capacitance,electrochemical stability,and rate performance.Especially,the assembled symmetrical K^(+)supercapacitor demonstrates an energy density of 51.8 Wh kg^(−1),an ultrahigh power density of 443Wkg^(−1),and outstanding cycling stability(maintaining 83.3%after 10,000 cycles in 1M KPF6 organic electrolyte).This research provides valuable insights into the design of highperformance potassium ion storage materials.展开更多
Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footpri...Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on MBenes,but mostly focused on C_(1) products.C^(2+) chemicals generally possess higher energy densities and wider applications than C_(1) counterparts.However,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process.Here,we explore electrochemical CO reduction reaction to C_(2) chemicals on Mo_(2)B_(2)O_(2) MBene via density-functional theory calculations.Remarkably,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)B_(2)O_(2) an efficient catalyst for C–C coupling.Among C_(1) and C_(2) chemicals,ethanol is predicted to be the primary product.Furthermore,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1) intermediates,which is responsible for the facile C–C coupling.From an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)B_(2)O_(2) a promising catalyst for electrochemical CO reduction to C_(2) chemicals.展开更多
目的了解A、B、AB型全血加入O型全血不同剂量后血型正反鉴定、抗-A、抗-B抗体效价、直接与间接抗人-IgG实验变化。方法完全随机抽取4℃保存24 h A、B、AB型全血分别60 m l,按不同比例加入O型抗-A、抗-B效价1∶64的全血9、12、15、18 m ...目的了解A、B、AB型全血加入O型全血不同剂量后血型正反鉴定、抗-A、抗-B抗体效价、直接与间接抗人-IgG实验变化。方法完全随机抽取4℃保存24 h A、B、AB型全血分别60 m l,按不同比例加入O型抗-A、抗-B效价1∶64的全血9、12、15、18 m l置入100 m l塑料血袋内混匀后,置37℃孵箱,间隔15 m in摇动1次。分别在1、2、4、8、12、24 h留取标本,做血型正反鉴定、抗-A、抗-B抗体效价、直接与间接抗人-IgG实验。结果不同型全血加入不同剂量O型全血,37℃不同时间血型正反鉴定相符;相对应抗-A、抗-B抗体效价逐渐下降到消失;直接与间接抗人-IgG实验的变化,以B型接受O型的反应最小,在接受600 m l直接与间接抗人-IgG均为阴性,800 m l同1 200 m l反应基本一致。A、AB型接受O型后直接与间接抗人-IgG反应基本一致,实验结果均为阳性。结论以B型接受O型的反应最小,在接受600 m l直接与间接抗人-IgG均为阴性。800 m l同1 200 m l反应基本一致,A、AB型直接与间接抗人-IgG均为阳性。原则上最好不输O型全血,从直接抗人-IgG实验分析,只要红细胞上存在不完全抗体,就一定会影响红细胞的寿命与质量。展开更多
文摘BACKGROUND Characteristics of alterations of serum hepatitis B virus(HBV) RNA in different chronic hepatitis B(CHB) patients still cannot be fully explained. Whether HBV RNA can predict HBeAg seroconversion is still controversial.AIM To investigate whether HBV RNA can predict virological response or HBeAg seroconversion during entecavir(ETV) treatment when HBV DNA is undetectable.METHODS The present study evaluated 61 individuals who were diagnosed and treated with long-term ETV monotherapy at the Department of Infectious Diseases of Peking University First Hospital(China) from September 2006 to December 2007.Finally, 30 treatment-naive individuals were included. Serum HBV RNA were extracted from 140 μL serum samples at two time points. Then they were reverse transcribed to cDNA with the HBV-specific primer. The product was quantified by real-time quantitative PCR(RT-PCR) using TAMARA probes. Statistical analyses were performed with IBM SPSS 20.0.RESULTS Level of serum HBV RNA at baseline was 4.15 ± 0.90 log10 copies/mL. HBV RNA levels showed no significant difference between the virological response(VR)and partial VR(PVR) groups at baseline(P = 0.940). Serum HBV RNA significantly decreased among patients who achieved a VR during ETV therapy(P < 0.001). The levels of HBV RNA in both HBeAg-positive patients with seroconversion group and those with no seroconversion increased after 24 wk of treatment. Overall, HBV RNA significantly but mildly correlated to HBsAg(r =0.265, P = 0.041), and HBV RNA was not correlated to HBV DNA(r = 0.242, P =0.062). Furthermore, serum HBV RNA was an independent indicator for predicting HBeAg seroconversion and virological response. HBeAg seroconversion was more likely in CHB patients with HBV RNA levels below4.12 log10 copies/mL before treatment.CONLUSION The level of serum HBV RNA could predict HBeAg seroconversion and PVR during treatment. In the PVR group, the level of serum HBV RNA tends to be increasing.
基金Supported by Research grant from the Ministry of Health,Labor,and Welfare of Japan
文摘AIM: To investigate the role of pre-core and basal core promoter(BCP) mutations before and after hepatitis Be antigen(HBe Ag) seroconversion.METHODS: The proportion of pre-core(G1896A) and basal core promoter(A1762T and G1764A) mutant viruses and serum levels of hepatitis B virus(HBV) DNA, hepatitis B surface antigen(HBs Ag), and HB core-related antigen were analyzed in chronic hepatitis B patients before and after HBe Ag seroconversion(n = 25), in those who were persistently HBe Ag positive(n = 18), and in those who were persistently anti-HBe positive(n = 43). All patients were infected with HBV genotype C and were followed for a median of 9 years.RESULTS: Although the pre-core mutant became predominant(24% to 65%, P = 0.022) in the HBe Ag seroconversion group during follow-up, the proportion of the basal core promoter mutation did not change. Median HBV viral markers were significantly higher in patients without the mutations in an HBe Ag positive status(HBV DNA: P = 0.003; HBs Ag: P < 0.001; HB core-related antigen: P = 0.001). In contrast, HBV DNA(P = 0.012) and HBs Ag(P = 0.041) levels were significantly higher in patients with the pre-core mutation in an anti-HBe positive status.CONCLUSION: There is an opposite association of the pre-core mutation with viral load before and after HBe Ag seroconversion in patients with HBV infection.
基金Supported by National Natural Science Foundation of China,Grant No.81241073Peking University Cancer Hospital Foundation for Scientific Research,Grant No.2013-Autonomous-9
文摘Reactivation of hepatitis B virus(HBV)can occur in lymphoma patients infected with HBV when they receive chemotherapy or immunotherapy.Prophylactic administration of lamivudine(LAM)reduces the morbidity and mortality associated with HBV reactivation.However,what defines HBV reactivation and the optimal duration of treatment with LAM have not yet been clearly established.HBV reactivation may occur due to the cessation of prophylactic LAM,although re-treatment with nucleoside analogs may sometimes result in hepatitis B surface antigen(HBsAg)seroconversion,which is a satisfactory endpoint for the management of HBV infection.We report a case of HBV reactivation in a 68-year-old HBsAg-positive patient who received rituximab-based immunochemotherapy for follicular lymphoma.HBV reactivation developed following cessation of prophylactic LAM therapy.The patient subsequently received treatment with entecavir(ETV),which led to a rapid and sustained suppression of HBV replication and HBsAg seroconversion.We also appraised the literature concerning HBV reactivation and the role of ETV in the management of HBV reactivation in lymphoma patients.A total of 28 cases of HBV reactivation have been reported as having been treated with ETV during or after immunosuppressive chemotherapy in lymphoma patients.We conclude that ETV is an efficacious and safe treatment for HBV reactivation following LAM cessation in lymphoma patients treated with rituximab-based immunochemotherapy.
基金by National Science and Technology Major Project,No.2017ZX10302201,No.2017ZX09304004 and No.2014ZX10002002National Program on Key Basic Research Project(973 Program),No.2015CB554304.
文摘BACKGROUND Quantitative hepatitis B core-related antigen(qHBcrAg)has a better correlation with intrahepatic hepatitis B virus(HBV)covalently closed circular DNA(cccDNA)than HBV DNA or hepatitis B e antigen(HBeAg),but data are still lacking for its clinical application.AIM The aim was to investigate serum qHBcrAg levels in patients with chronic hepatitis B and assess the correlation of serum qHBcrAg with pregenomic RNA(pgRNA),cccDNA,and HBeAg seroconversion.METHODS This study was a secondary analysis of patients who underwent percutaneous liver biopsy between July 2014 and June 2019 in two multicenter randomized controlled clinical trials of peginterferon vs nucleos(t)ide analog(NUC)-based therapy(NCT03509688 and NCT03546530).Serum qHBcrAg,pgRNA,HBV DNA,hepatitis B core antigen,HBeAg,liver cccDNA,and HBV DNA were measured.The correlations of serum qHBcrAg with other biomarkers were analyzed.RESULTS A total of 139 patients were included.The mean qHBcrAg levels were 5.32±1.18 log10 U/mL at baseline and decreased during treatment(all P<0.0001).Serum qHBcrAg levels were positively correlated with pgRNA(r=0.597,P<0.0001)and cccDNA(r=0.527,P<0.0001)levels.The correlation of serum qHBcrAg level and intrahepatic HBV DNA levels at baseline was weak but significant(r=0.399,P<0.0001).HBcrAg predicted HBeAg seroconversion,with areas under the receiver operating characteristics curve of 0.788 at 24 wk and 0.825 at 48 wk.Log HBcrAg at wk 24 and 48 was independently associated with HBeAg seroconversion[odds ratio(OR)=2.402,95%confidence interval(CI):1.314-4.391,P=0.004;OR=3.587,95%CI:1.315-9.784,P=0.013].CONCLUSION Serum HBcrAg levels were correlated with HBV virological markers and could be used to predict HBeAg seroconversion.
基金supported by Ningbo Natural Science Foundation (No. 2012A610183 No. 2013A610239)
文摘Objective To investigate the efficiency of pegylated interferon α therapy for patients with HBe Ag-positive chronic hepatitis B(CHB) and explore whether liver histopathological features and other factors might influence HBe Ag seroconversion.Methods Total of 80 HBe Ag-positive CHB patients who received liver puncture were treated with pegylated interferon α once a week for 48 weeks. The rate of HBe Ag seroconversion was determined after therapy, and the factors influencing HBe Ag seroconversion were analyzed.Results The rate of HBe Ag seroconversion was 30.00% at the end of treatment. The rate of HBe Ag seroconversion gradually increased with the elevation of liver inflammatory activity(χ2 = 9.170, P = 0.027). But liver fibrosis has little correlation with the rate of HBeA g seroconversion(χ2 = 5.917, P = 0.116). Except HBeA g, other baseline indexes including gender, age, serum ALT and serum HBV DNA 1evels had no statistical difference between the patients with HBe Ag seroconversion and the patients without HBe Ag seroconversion. By binary logistic regression analysis, liver inflammation and HBeA g were influencing factors for HBeA g seroconversion. Conclusions Pegylated interferon α therapy induces a higher rate of HBeA g seroconversion in HBeA g-positive chronic hepatitis B patients with severe liver inflammation, so the liver biopsies should be performed in time.
文摘<strong>Introduction: </strong>The risk of transmission of pathogens such as hepatitis B virus threatens the safety of transfused patients especially in high endemic areas. The aim of this study was to determine the incidence and factors associated with hepatitis B virus surface antigen (HBsAg) seroconversion in blood donors at the Regional Blood Transfusion Centre of Ouagadougou. <strong>Methods:</strong> A retrospective cohort study of voluntary non-remunerated blood donors (VNRBD), was conducted from 2008 to 2017. Data on HBsAg seroconversion were collected. The Kaplan-Meier method and the Log-Rank test were used to estimate the survival curves. Cox’s regression identified the factors associated with this seroconversion. <strong>Results:</strong> Of 23,494 donors, 559 had HBsAg seroconversion. The number of donor years was 58,637.50 and the HBV incidence rate was 9.53 per 1000 donor years. The median seroconversion time was 75.73 months with extremes of 2.7 months and 107.12 months. The risk of seroconversion was 1.30 times higher among donors aged 21 to 24 years old (p = 0.007) and 2.49 times higher among those over 24 years old (p < 0.0001) than among donors under 21 years old. Female donors were 1.11 times more likely to seroconvert than male donors (p = 0.33). Donor residence was not significantly associated with HBsAg seroconversion (Hazard ratio = 1.12;p = 0.36). The risk of seroconversion decreased significantly with the number of blood donations (Hazard ratio = 0.58;p = 0.006). <strong>Conclusion: </strong>The incidence of HBsAg remains high among blood donors, which could have a negative impact on transfusion safety. The age of the blood donor was significantly associated to AgHBs seroconversion.
基金financially supported by the Natural Science Foundation of China(Grant No.22005165)the Major Science and Technology Innovation Project of Shandong(Grant No.2019JZZY010507)+1 种基金the Qingdao Municipal Science and Technology Bureau(Grant No.17-1-1-86-jch)the Key Technology Research and Development Program of Shandong(Grant No.2018GGX108005).
文摘The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of the electronic structure from single-atom doping to heteroatom codoping in CAs has not yet been thoroughly investigated,and the impact of codoping on potassium ion(K+)storage and diffusion pathways as electrode material remains unclear.In this study,experimental and theoretical simulations were conducted to demonstrate that heteroatom codoping,composed of multiple heteroatoms(O/N/B)with different properties,has the potential to improve the electrical properties and stability of CAs compared to single-atom doping.Electronic states near the Fermi level have revealed that doping with O/N/B generates a greater number of active centers on adjacent carbon atoms than doping with O and O/N atoms.As a result of synergy with enhanced wetting ability(contact angle of 9.26°)derived from amino groups and hierarchical porous structure,ON-CA has the most optimized adsorption capacity(−1.62 eV)and diffusion barrier(0.12 eV)of K^(+).The optimal pathway of K^(+)in ON-CA is along the carbon ring with N or O doping.As K^(+)storage material for supercapacitors and ion batteries,it shows an outstanding specific capacity and capacitance,electrochemical stability,and rate performance.Especially,the assembled symmetrical K^(+)supercapacitor demonstrates an energy density of 51.8 Wh kg^(−1),an ultrahigh power density of 443Wkg^(−1),and outstanding cycling stability(maintaining 83.3%after 10,000 cycles in 1M KPF6 organic electrolyte).This research provides valuable insights into the design of highperformance potassium ion storage materials.
基金the A*STAR LCER-FI project(LCERFI01-0033 U2102d2006)the Ministry of Education of Singapore and the National University of Singapore(C-261-000-207-532/C-261-000-777-532 and R-279-000-574-114)for financial support.
文摘Emerging as a new class of two-dimensional materials with atomically thin layers,MBenes have great potential for many important applications such as energy storage and electrocatalysis.Toward mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on MBenes,but mostly focused on C_(1) products.C^(2+) chemicals generally possess higher energy densities and wider applications than C_(1) counterparts.However,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process.Here,we explore electrochemical CO reduction reaction to C_(2) chemicals on Mo_(2)B_(2)O_(2) MBene via density-functional theory calculations.Remarkably,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)B_(2)O_(2) an efficient catalyst for C–C coupling.Among C_(1) and C_(2) chemicals,ethanol is predicted to be the primary product.Furthermore,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1) intermediates,which is responsible for the facile C–C coupling.From an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)B_(2)O_(2) a promising catalyst for electrochemical CO reduction to C_(2) chemicals.
文摘目的了解A、B、AB型全血加入O型全血不同剂量后血型正反鉴定、抗-A、抗-B抗体效价、直接与间接抗人-IgG实验变化。方法完全随机抽取4℃保存24 h A、B、AB型全血分别60 m l,按不同比例加入O型抗-A、抗-B效价1∶64的全血9、12、15、18 m l置入100 m l塑料血袋内混匀后,置37℃孵箱,间隔15 m in摇动1次。分别在1、2、4、8、12、24 h留取标本,做血型正反鉴定、抗-A、抗-B抗体效价、直接与间接抗人-IgG实验。结果不同型全血加入不同剂量O型全血,37℃不同时间血型正反鉴定相符;相对应抗-A、抗-B抗体效价逐渐下降到消失;直接与间接抗人-IgG实验的变化,以B型接受O型的反应最小,在接受600 m l直接与间接抗人-IgG均为阴性,800 m l同1 200 m l反应基本一致。A、AB型接受O型后直接与间接抗人-IgG反应基本一致,实验结果均为阳性。结论以B型接受O型的反应最小,在接受600 m l直接与间接抗人-IgG均为阴性。800 m l同1 200 m l反应基本一致,A、AB型直接与间接抗人-IgG均为阳性。原则上最好不输O型全血,从直接抗人-IgG实验分析,只要红细胞上存在不完全抗体,就一定会影响红细胞的寿命与质量。