Infection caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV2)virus,responsible for the coronavirus disease 2019(COVID-19)pandemic,induces symptoms including increased inflammatory response,severe ...Infection caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV2)virus,responsible for the coronavirus disease 2019(COVID-19)pandemic,induces symptoms including increased inflammatory response,severe acute respiratory syndrome(SARS),cognitive dysfunction like brain fog,and cardiovascular defects.Long-term effects of SARS-CoV2 COVID-19 syndrome referred to as post-COVID-19 syndrome on age-related progressive neurodegenerative disorders such as Alzheimer's disease remain understudied.Using the targeted misexpression of individual SARS-CoV2 proteins in the retinal neurons of the Drosophila melanogaster eye,we found that misexpression of nonstructural protein 3(Nsp3),a papain-like protease,ablates the eye and generates dark necrotic spots.Targeted misexpression of Nsp3 in the eye triggers reactive oxygen species production and leads to apoptosis as shown by cell death reporters,terminal deoxynucleotidyl transferase(TdT)dUTP Nick-end labeling(TUNEL)assay,and dihydroethidium staining.Furthermore,Nsp3 misexpression activates both apoptosis and autophagy mechanism(s)to regulate tissue homeostasis.Transient expression of SARS-CoV2 Nsp3 in murine neuroblastoma,Neuro-2a cells,significantly reduced the metabolic activity of these cells and triggers cell death.Misexpression of SARS-CoV2 Nsp3 in an Alzheimer's disease transgenic fly eye model(glass multiple repeats[GMR]>amyloidβ42)further enhances the neurodegenerative rough eye phenotype due to increased cell death.These findings suggest that SARS-CoV2 utilizes Nsp3 protein to potentiate cell death response in a neurodegenerative disease background that has high pre-existing levels of neuroinflammation and cell death.展开更多
Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to...Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. Patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30<sup>th</sup> to August 30<sup>th</sup>, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. Moreover, the induced protection was neither strong nor durable, particularly in patients with longer duration in dialysis.展开更多
Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures a...Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures against SARS-Cov2 in haemodialysis patients. Methods and Material: From 13 to 19 July 2021, we administered the questionnaire to haemodialysis patients during or immediately after the dialysis session. The dependent variables were adherence to wearing masks, hand washing outside the dialysis centre, social distancing of at least 1.5 meters, and cough and sneeze hygiene. Statistical Analysis Used: Data were analyzed using Epi info software;descriptive statistics were presented as mean, headcount, and percentage;related factors were determined by multi-logistic regression. The significance level was 5%. The Health Research Ethics Committee approved the research protocol. Results: 142 patients were included (mean age: 42.5 ± 14 years). Wearing masks, hand-washing, social distancing, and coughing and sneezing hygiene were observed by 88%, 75%, 47%, and 60% of patients, respectively. Conclusion: Wearing masks was the most respected physical measure, while social distancing was the least respected.展开更多
目的:以减毒沙门氏菌为载体运送SARS-CoV N DNA疫苗至小鼠体内,研究其诱导的免疫应答情况,评价减毒鼠伤寒沙门氏菌作为口服疫苗的免疫效果。方法:将含SARS-CoVN基因的pcDNA-N质粒导入减毒鼠伤寒沙门氏菌CS022中,采用口服和滴鼻相结合的...目的:以减毒沙门氏菌为载体运送SARS-CoV N DNA疫苗至小鼠体内,研究其诱导的免疫应答情况,评价减毒鼠伤寒沙门氏菌作为口服疫苗的免疫效果。方法:将含SARS-CoVN基因的pcDNA-N质粒导入减毒鼠伤寒沙门氏菌CS022中,采用口服和滴鼻相结合的方法免疫BALB/c小鼠,以ELISA检测不同时间免疫小鼠血清中抗体及其亚型;以MTT法测定特异性淋巴细胞增殖反应;ELISPOT检测细胞因子;流式检测T细胞亚型。结果:pcDNA-N DNA疫苗口服免疫后2周就可以诱生特异性IgG抗体,且以IgG2a占优势;诱导了较高水平的淋巴细胞特异性增殖反应和IFN-γ,主要以Th1免疫为主。结论:减毒沙门氏菌可以有效运送pcDNA-N重组质粒并诱导产生特异体液和细胞免疫应答,为减毒细菌作为DNA疫苗运送载体的研究提供了参考依据,也为SARS疫苗研究开辟了新方法。展开更多
基金supported by 1RO1EY032959-01 from NIHSchuellein Chair Endowment FundSTEM Catalyst Grant from the University of Dayton(all to AS)。
文摘Infection caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV2)virus,responsible for the coronavirus disease 2019(COVID-19)pandemic,induces symptoms including increased inflammatory response,severe acute respiratory syndrome(SARS),cognitive dysfunction like brain fog,and cardiovascular defects.Long-term effects of SARS-CoV2 COVID-19 syndrome referred to as post-COVID-19 syndrome on age-related progressive neurodegenerative disorders such as Alzheimer's disease remain understudied.Using the targeted misexpression of individual SARS-CoV2 proteins in the retinal neurons of the Drosophila melanogaster eye,we found that misexpression of nonstructural protein 3(Nsp3),a papain-like protease,ablates the eye and generates dark necrotic spots.Targeted misexpression of Nsp3 in the eye triggers reactive oxygen species production and leads to apoptosis as shown by cell death reporters,terminal deoxynucleotidyl transferase(TdT)dUTP Nick-end labeling(TUNEL)assay,and dihydroethidium staining.Furthermore,Nsp3 misexpression activates both apoptosis and autophagy mechanism(s)to regulate tissue homeostasis.Transient expression of SARS-CoV2 Nsp3 in murine neuroblastoma,Neuro-2a cells,significantly reduced the metabolic activity of these cells and triggers cell death.Misexpression of SARS-CoV2 Nsp3 in an Alzheimer's disease transgenic fly eye model(glass multiple repeats[GMR]>amyloidβ42)further enhances the neurodegenerative rough eye phenotype due to increased cell death.These findings suggest that SARS-CoV2 utilizes Nsp3 protein to potentiate cell death response in a neurodegenerative disease background that has high pre-existing levels of neuroinflammation and cell death.
文摘Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. Patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30<sup>th</sup> to August 30<sup>th</sup>, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. Moreover, the induced protection was neither strong nor durable, particularly in patients with longer duration in dialysis.
文摘Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures against SARS-Cov2 in haemodialysis patients. Methods and Material: From 13 to 19 July 2021, we administered the questionnaire to haemodialysis patients during or immediately after the dialysis session. The dependent variables were adherence to wearing masks, hand washing outside the dialysis centre, social distancing of at least 1.5 meters, and cough and sneeze hygiene. Statistical Analysis Used: Data were analyzed using Epi info software;descriptive statistics were presented as mean, headcount, and percentage;related factors were determined by multi-logistic regression. The significance level was 5%. The Health Research Ethics Committee approved the research protocol. Results: 142 patients were included (mean age: 42.5 ± 14 years). Wearing masks, hand-washing, social distancing, and coughing and sneezing hygiene were observed by 88%, 75%, 47%, and 60% of patients, respectively. Conclusion: Wearing masks was the most respected physical measure, while social distancing was the least respected.
文摘目的:以减毒沙门氏菌为载体运送SARS-CoV N DNA疫苗至小鼠体内,研究其诱导的免疫应答情况,评价减毒鼠伤寒沙门氏菌作为口服疫苗的免疫效果。方法:将含SARS-CoVN基因的pcDNA-N质粒导入减毒鼠伤寒沙门氏菌CS022中,采用口服和滴鼻相结合的方法免疫BALB/c小鼠,以ELISA检测不同时间免疫小鼠血清中抗体及其亚型;以MTT法测定特异性淋巴细胞增殖反应;ELISPOT检测细胞因子;流式检测T细胞亚型。结果:pcDNA-N DNA疫苗口服免疫后2周就可以诱生特异性IgG抗体,且以IgG2a占优势;诱导了较高水平的淋巴细胞特异性增殖反应和IFN-γ,主要以Th1免疫为主。结论:减毒沙门氏菌可以有效运送pcDNA-N重组质粒并诱导产生特异体液和细胞免疫应答,为减毒细菌作为DNA疫苗运送载体的研究提供了参考依据,也为SARS疫苗研究开辟了新方法。