PTEN inhibitor bisperoxovanadium protects against noise-induced hearing loss

Studies have shown that phosphatase and tensin homolog deleted on chromosome ten(PTEN)participates in the regulation of cochlear hair cell survival.Bisperoxovanadium protects against neurodegeneration by inhibiting PTEN expression.However,whether bisperoxovanadium can protect against noise-induced hearing loss and the underlying mechanism remains unclear.In this study,we established a mouse model of noise-induced hearing loss by exposure to 105 dB sound for 2 hours.We found that PTEN expression was increased in the organ of Corti,including outer hair cells,inner hair cells,and lateral wall tissues.Intraperitoneal administration of bisperoxovanadium decreased the auditory threshold and the loss of cochlear hair cells and inner hair cell ribbons.In addition,noise exposure decreased p-PI3K and p-Akt levels.Bisperoxovanadium preconditioning or PTEN knockdown upregulated the activity of PI3K-Akt.Bisperoxovanadium also prevented H_(2)O_(2)-induced hair cell death by reducing mitochondrial reactive oxygen species generation in cochlear explants.These findings suggest that bisperoxovanadium reduces noise-induced hearing injury and reduces cochlear hair cell loss.

Optimum interval time of programmed intermittent epidural bolus of ropivacaine 0.08%with sufentanyl 0.3 mg/mL for labor analgesia:a biased-coin up-and-down sequential allocation trial

Background:The programmed intermittent epidural bolus(PIEB)technique is widely used in labor analgesia,but the parameter settings of PIEB have not yet been standardized.We designed a study to identify the optimal interval duration for PIEB using 10 mL of ropivacaine 0.08%and sufentanyl 0.3 mg/mL,a regimen commonly used to control labor pain in China,to provide effective analgesia in 90%of women during the first stage of labor without breakthrough pain.Methods:We conducted a double-blind sequential allocation trial to obtain the effective interval 90%(EI90%)during the first stage of labor between April 2019 and May 2019.This study included the American Society of Anesthesiologists physical status II–III nulliparous parturients at term,who requested epidural analgesia.The bolus volume was fixed at 10 mL of ropivacaine 0.08%with sufentanyl 0.3 mg/mL.Participants were divided into four groups(groups 60,50,40,and 30)according to the PIEB intervals(60,50,40,and 30 min,respectively).The interval duration of the first parturient was set at 60 min and that of subsequent parturients varied according to a biased-coin design.The truncated Dixon and Mood method and the isotonic regression analysis method were used to estimate the EI90%and its 95%confidence intervals(CIs).Results:Forty-four women were enrolled in this study.The estimated optimal interval was 44.1 min(95%CI 41.7–46.5 min)and 39.5 min(95%CI 32.5–50.0 min),using the truncated Dixon and Mood method and isotonic regression analysis,respectively.The maximum sensory block level above T6 was in nearly 20%of parturients in group 30;however,5.3%,0%,and 0%of the parturients presented with sensory block level above T6 in groups 40,50,and 60,respectively.There were no cases of hypotension and only one parturient complained of motor block.Conclusion:With a fixed 10 mL dose of ropivacaine 0.08%with sufentanyl 0.3 mg/mL,the optimal PIEB interval is about 42 min.Further studies are warranted to define the efficacy of this regimen throughout all stages of labor.

Enhanced recovery after cesarean delivery:a challenge for anesthesiologists

Enhanced recovery after cesarean(ERAC)delivery is an evidence-based,multi-disciplinary approach throughout pre-,intra-,postoperative period.The ultimate goal of ERAC is to enhance recovery and improve the maternal and neonatal outcomes.This review highlights the role of anesthesiologist in ERAC protocols.This review provided a general introduction of ERAC including the purposes and the essential elements of ERAC protocols.The tool used for evaluating the quality of ERAC(ObsQoR-11)was discussed.The role of anesthesiologist in ERAC should cover the areas including management of peri-operative hypotension,prevention and treatment of intra-and post-operative nausea and vomiting,prevention of hypothermia and multi-modal perioperative pain management,and active pre-operative management of unplanned conversion of labor analgesia to cesarean delivery anesthesia.Although some concerns still remain,ERAC implementation should not be delayed.Regular assessment and process improvement should be imbedded into the protocol.Further high-quality studies are warranted to demonstrate the effectiveness and efficacy of the ERAC protocol.