The coronavirus disease 2019(COVID-19)pandemic has caused changes in the global health system,causing significant setbacks in healthcare systems worldwide.This pandemic has also shown resilience,flexibility,and creati...The coronavirus disease 2019(COVID-19)pandemic has caused changes in the global health system,causing significant setbacks in healthcare systems worldwide.This pandemic has also shown resilience,flexibility,and creativity in reacting to the tragedy.The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection targets most of the respiratory tract,resulting in a severe sickness called acute respiratory distress syndrome that may be fatal in some individuals.Although the lung is the primary organ targeted by COVID-19 viruses,the clinical aspect of the disease is varied and ranges from asymptomatic to respiratory failure.However,due to an unorganized immune response and several affected mechanisms,the liver may also experience liver cell injury,ischemic liver dysfunction,and drug-induced liver injury,which can result in respiratory failure because of the immune system’s disordered response and other compromised processes that can end in multisystem organ failure.Patients with liver cirrhosis or those who have impaired immune systems may be more likely than other groups to experience worse results from the SARS-CoV-2 infection.We thus intend to examine the pathogenesis,current therapy,and consequences of liver damage concerning COVID-19.展开更多
Mining of plant-derived antimicrobials is the major focus at current to counter antibiotic resistance. This study was conducted to characterize the antimicrobial activity and mode of action of linalyl anthranilate(LNA...Mining of plant-derived antimicrobials is the major focus at current to counter antibiotic resistance. This study was conducted to characterize the antimicrobial activity and mode of action of linalyl anthranilate(LNA) against carbapenemase-producing Klebsiella pneumoniae(KPC-KP). LNA alone exhibited bactericidal activity at 2.5%(V/V), and in combination with meropenem(MPM) at 1.25%(V/V). Comparative proteomic analysis showed a significant reduction in the number of cytoplasmic and membrane proteins,indicating membrane damage in LNA-treated KPC-KP cells. Up-regulation of oxidative stress regulator proteins and down-regulation of oxidative stress-sensitive proteins indicated oxidative stress. Zeta potential measurement and outer membrane permeability assay revealed that LNA increases both bacterial surface charge and membrane permeability. Ethidium bromide influx/efflux assay showed increased uptake of ethidium bromide in LNA-treated cells, inferring membrane damage. Furthermore, intracellular leakage of nucleic acid and proteins was detected upon LNA treatment. Scanning and transmission electron microscopies again revealed the breakage of bacterial membrane and loss of intracellular materials. LNA was found to induce oxidative stress by generating reactive oxygen species(ROS) that initiate lipid peroxidation and damage the bacterial membrane. In conclusion, LNA generates ROS, initiates lipid peroxidation, and damages the bacterial membrane, resulting in intracellular leakage and eventually killing the KPC-KP cells.展开更多
文摘The coronavirus disease 2019(COVID-19)pandemic has caused changes in the global health system,causing significant setbacks in healthcare systems worldwide.This pandemic has also shown resilience,flexibility,and creativity in reacting to the tragedy.The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection targets most of the respiratory tract,resulting in a severe sickness called acute respiratory distress syndrome that may be fatal in some individuals.Although the lung is the primary organ targeted by COVID-19 viruses,the clinical aspect of the disease is varied and ranges from asymptomatic to respiratory failure.However,due to an unorganized immune response and several affected mechanisms,the liver may also experience liver cell injury,ischemic liver dysfunction,and drug-induced liver injury,which can result in respiratory failure because of the immune system’s disordered response and other compromised processes that can end in multisystem organ failure.Patients with liver cirrhosis or those who have impaired immune systems may be more likely than other groups to experience worse results from the SARS-CoV-2 infection.We thus intend to examine the pathogenesis,current therapy,and consequences of liver damage concerning COVID-19.
基金supported by the Higher College of Technology (HCT) Interdisciplinary Research Grant (Grant No. 113118)the Malaysian Medical Association Grant, and the UCSI PSIF Grant (Grant No. Proj-2019-In-Fas-062)。
文摘Mining of plant-derived antimicrobials is the major focus at current to counter antibiotic resistance. This study was conducted to characterize the antimicrobial activity and mode of action of linalyl anthranilate(LNA) against carbapenemase-producing Klebsiella pneumoniae(KPC-KP). LNA alone exhibited bactericidal activity at 2.5%(V/V), and in combination with meropenem(MPM) at 1.25%(V/V). Comparative proteomic analysis showed a significant reduction in the number of cytoplasmic and membrane proteins,indicating membrane damage in LNA-treated KPC-KP cells. Up-regulation of oxidative stress regulator proteins and down-regulation of oxidative stress-sensitive proteins indicated oxidative stress. Zeta potential measurement and outer membrane permeability assay revealed that LNA increases both bacterial surface charge and membrane permeability. Ethidium bromide influx/efflux assay showed increased uptake of ethidium bromide in LNA-treated cells, inferring membrane damage. Furthermore, intracellular leakage of nucleic acid and proteins was detected upon LNA treatment. Scanning and transmission electron microscopies again revealed the breakage of bacterial membrane and loss of intracellular materials. LNA was found to induce oxidative stress by generating reactive oxygen species(ROS) that initiate lipid peroxidation and damage the bacterial membrane. In conclusion, LNA generates ROS, initiates lipid peroxidation, and damages the bacterial membrane, resulting in intracellular leakage and eventually killing the KPC-KP cells.