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Human infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause coronavirus disease 19 (COVID-19) and there is currently no cure. The 3C-like protease (3CLpro), a highly conserved protease indispensable for replication of coronaviruses, is a promising target for development of broad-spectrum antiviral drugs. To advance the speed of drug discovery and development, we investigated the inhibition of SARS-CoV-2 3CLpro by natural products derived from Chinese traditional medicines. Baicalin and baicalein were identified as the first non-covalent, non-peptidomimetic inhibitors of SARS-CoV-2 3CLpro and exhibited potent antiviral activities in a cell-based system. Remarkably, the binding mode of baicalein with SARS-CoV-2 3CLpro determined by X-ray protein crystallography is distinctly different from those of known inhibitors. Baicalein is perfectly ensconced in the core of the substrate-binding pocket by interacting with two catalytic residues, the crucial S1/S2 subsites and the oxyanion loop, acting as a "shield" in front of the catalytic dyad to prevent the peptide substrate approaching the active site. The simple chemical structure, unique mode of action, and potent antiviral activities in vitro, coupled with the favorable safety data from clinical trials, emphasize that baicalein provides a great opportunity for the development of critically needed anti-coronaviral drugs.
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Objective@#To compare the efficacy of femoral triangle versus adductor canal approach to saphenous nerve block for postoperative analgesia in the patients undergoing knee arthroplasty.@*Methods@#Sixty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients of both sexes, aged 53-68 yr, scheduled for elective total knee arthroplasty under general anesthesia, were assigned into 2 groups (n=30 each) using a random number table method: femoral triangle approach to saphenous nerve block group (group F) and adductor canal approach to saphenous nerve block group (group A). Femoral triangle and adductor canal approach to saphenous nerve block was performed by injecting 0.5% ropivacaine 20 ml in group F and group A, respectively.Patient-controlled saphenous nerve block analgesia was used in two groups, and the analgesic pump solution contained 1% ropivacaine 400 mg diluted to 160 ml in 0.9% sodium chloride injection.The analgesic pump was set up with a 5 ml bolus dose, a 30-min lockout interval and background infusion at a rate of 5 ml/h, and analgesia lasted until 72 h after operation.When visual analog scale score > 4 and pain was not relived after 30-min pressing by patients, pethidine hydrochloride 100 mg was intramuscularly injected as rescue analgesic.The muscle strength of quadriceps femoris was assessed by manual muscle test at 4, 8, 24, 48 and 72 h after operation.The patient′s satisfaction score was assessed and recorded at 72 h after operation.Rescue analgesia and development of adverse reactions (local anesthetic intoxication, itching, dizziness, urinary retention, nausea and vomiting) were recorded within 72 h after operation.@*Results@#Compared with group F, the muscle strength of quadriceps femoris was significantly increased at 4, 8 and 24 h after operation, the rate of postoperative rescue analgesia was decreased (P<0.05), and no significant change was found in patient′s satisfaction score or incidence of adverse reactions in group A (P>0.05).@*Conclusion@#Adductor canal approach to saphenous nerve block provides better efficacy for postoperative analgesia than femoral triangle approach to saphenous nerve block in the patients undergoing knee arthroplasty.
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Objective To compare the efficacy of femoral triangle versus adductor canal approach to saphenous nerve block for postoperative analgesia in the patients undergoing knee arthroplasty.Methods Sixty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients of both sexes,aged 53-68yr,scheduled for elective total knee arthroplasty under general anesthesia,were assigned into 2 groups (n=30 each) using a random number table method:femoral triangle approach to saphenous nerve block group (group F) and adductor canal approach to saphenous nerve block group (group A).Femoral triangle and adductor canal approach to saphenous nerve block was performed by injecting 0.5％ ropivacaine 20 ml in group F and group A,respectively.Patient-controlled saphenous nerve block analgesia was used in two groups,and the analgesic pump solution contained 1％ ropivacaine 400 mg diluted to 160 ml in 0.9％ sodium chloride injection.The analgesic pump was set up with a 5 ml bolus dose,a 30-main lockout interval and background infusion at a rate of 5 ml/h,and analgesia lasted until 72 h after operation.When visual analog scale score ＞ 4 and pain was not relived after 30-min pressing by patients,pethidine hydrochloride 100 mg was intramuscularly injected as rescue analgesic.The muscle strength of quadriceps femoris was assessed by manual muscle test at 4,8,24,48 and 72 h after operation.The patient's satisfaction score was assessed and recorded at 72 h after operation.Rescue analgesia and development of adverse reactions (local anesthetic intoxication,itching,dizziness,urinary retention,nausea and vomiting) were recorded within 72 h after operation.Results Compared with group F,the muscle strength of quadriceps femoris was significantly increased at 4,8 and 24 h after operation,the rate of postoperative rescue analgesia was decreased (P＜0.05),and no significant change was found in patient's satisfaction score or incidence of adverse reactions in group A (P＞0.05).Conclusion Adductor canal approach to saphenous nerve block provides better efficacy for postoperative analgesia than femoral triangle approach to saphenous nerve block in the patients undergoing knee arthroplasty.
