Mammalian cell surfaces consist of the plasma membrane supported by an underneath cortical cytoskeleton.Together,these structures can control not only the shape of cells but also a series of cellular functions ranging...Mammalian cell surfaces consist of the plasma membrane supported by an underneath cortical cytoskeleton.Together,these structures can control not only the shape of cells but also a series of cellular functions ranging from migration and division to exocytosis,endocytosis and differentiation.Furthermore,the cell surface is capable of exerting and reacting to mechanical forces.Its viscoelastic properties,especially membrane tension and bending modulus,are fundamental parameters involved in these responses.This viewpoint summarizes our current knowledge on how to measure the viscoelastic properties of cell surfaces employing optical tweezers-based tether assays,paving the way for a better understanding of how cells react to external mechanical forces,with a glance on their remodeling dynamics and possible consequences on downstream cellular processes.展开更多
Background: Respiratory tract infections were associated with acute exacerbations of heart failure (HF). However, the role of the influenza virus, a major agent of such infections, in this population remained unclear....Background: Respiratory tract infections were associated with acute exacerbations of heart failure (HF). However, the role of the influenza virus, a major agent of such infections, in this population remained unclear. Method: During the influenza virus seasons of 2013 and 2014 we prospectively assessed influenza respiratory illnesses in a cohort of adults primarily hospitalized for management of acute decompensated HF and a cohort of HF outpatients. Qualitative RT-PCR for?influenza?A (A/H1, A/H12009pdm, A/H3) and B virus testing was performed on nasopharyngeal swab samples. Result: A total of 121 patients were included, 58.3% males (n?= 70), mean age 57.7 years old (±14.0), mean left ejection fraction 35.3 (±9.8). Of these, 50.4% were inpatients (n?= 61). The prevalence of symptoms of respiratory infections was 28.0% (n?= 34) and 4.9% (n?= 6) of all samples were positive for influenza virus. Only influenza A was detected and all cases were among inpatients. Influenza-positive patients had a greater need for antimicrobials (83.3%,?n?= 5;16.3%,?n= 9;?p?= 0.001) and for mechanical ventilation (50.0%,?n?= 3;3.6%,?n?= 2;?p?< 0.001) than Influenza-negative patients. The prevalence of influenza virus was not related to mortality (OR 4.58;?p?= 0.16). Conclusion:?Although not common, the influenza virus infection resulted in worst outcomes, with a greater need for antimicrobials and mechanical ventilation. Immunization and antiviral treatment in high risk patients may positively impact their outcomes.展开更多
基金This work was supported by the Brazilian agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES)–Financial Code 001,Fundação de AmparoàPesquisa do Estado do Rio de Janeiro(FAPERJ)+1 种基金Fundação de AmparoàPesquisa do Estado do Amazonas(FAPEAM)Instituto Nacional de Ciência e Tecnologia de Fluidos Complexos(INCT-FCx)together with Fundação de AmparoàPesquisa do Estado de São Paulo(FAPESP).BP was supported by a JCNE grant from FAPERJ.
文摘Mammalian cell surfaces consist of the plasma membrane supported by an underneath cortical cytoskeleton.Together,these structures can control not only the shape of cells but also a series of cellular functions ranging from migration and division to exocytosis,endocytosis and differentiation.Furthermore,the cell surface is capable of exerting and reacting to mechanical forces.Its viscoelastic properties,especially membrane tension and bending modulus,are fundamental parameters involved in these responses.This viewpoint summarizes our current knowledge on how to measure the viscoelastic properties of cell surfaces employing optical tweezers-based tether assays,paving the way for a better understanding of how cells react to external mechanical forces,with a glance on their remodeling dynamics and possible consequences on downstream cellular processes.
文摘Background: Respiratory tract infections were associated with acute exacerbations of heart failure (HF). However, the role of the influenza virus, a major agent of such infections, in this population remained unclear. Method: During the influenza virus seasons of 2013 and 2014 we prospectively assessed influenza respiratory illnesses in a cohort of adults primarily hospitalized for management of acute decompensated HF and a cohort of HF outpatients. Qualitative RT-PCR for?influenza?A (A/H1, A/H12009pdm, A/H3) and B virus testing was performed on nasopharyngeal swab samples. Result: A total of 121 patients were included, 58.3% males (n?= 70), mean age 57.7 years old (±14.0), mean left ejection fraction 35.3 (±9.8). Of these, 50.4% were inpatients (n?= 61). The prevalence of symptoms of respiratory infections was 28.0% (n?= 34) and 4.9% (n?= 6) of all samples were positive for influenza virus. Only influenza A was detected and all cases were among inpatients. Influenza-positive patients had a greater need for antimicrobials (83.3%,?n?= 5;16.3%,?n= 9;?p?= 0.001) and for mechanical ventilation (50.0%,?n?= 3;3.6%,?n?= 2;?p?< 0.001) than Influenza-negative patients. The prevalence of influenza virus was not related to mortality (OR 4.58;?p?= 0.16). Conclusion:?Although not common, the influenza virus infection resulted in worst outcomes, with a greater need for antimicrobials and mechanical ventilation. Immunization and antiviral treatment in high risk patients may positively impact their outcomes.
