Objective:To develop a modified University of Wisconsin preservation solution (UW solution) containing α 2-adrenergic receptor agonists (dexmedetomidine) and noble gases (argon) and investigate its protective effect on the isolated amputated skeletal muscle of rats. Methods:Sixty male SD rats were selected to establish a hindlimb cold preservation/perfusion model and were divided into blank control group, hypothermic storage group, UW solution perfusion group, and modified UW solution perfusion group using a random number table, with 15 rats in each group. Simultaneously, a cold preservation model of rat skeletal muscle myoblasts (L6 cells) was established and the rats were also divided into four groups in the same way. Animal models were prepared in different ways: In the blank control group, the hindlimbs received no special treatment; In the hypothermic storage group, the amputated hindlimbs were stored in a dry centrifuge tube at 4℃ for 18 hours; In the UW solution perfusion group, the amputated hindlimbs were perfused with UW solution and then stored in a centrifuge tube containing UW solution at 4℃ for 18 hours; In the modified UW solution perfusion group, the amputated hindlimbs were perfused with modified UW solution (containing 0.1 nmol/L dexmedetomidine and 50% volume fraction of argon) and then stored in a centrifuge tube containing the modified UW solution at 4℃ for 18 hours. Cell models were treated as follows: In the blank control group, L6 cells were cultured under standard conditions; In the hypothermic storage group and UW solution group, L6 cells were treated with conventional culture medium or UW solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours; In the modified UW solution group, L6 cells were treated with the modified solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours. After sample collection, skeletal muscle morphology, tissue edema and ultrastructure features were assessed by HE staining, wet-to-dry weight ratio, and transmission electron microscopy, respectively. Additionally, L6 cell morphology was examined by light microscopy. L6 cell viability was determined by cell counting kit-8 (CCK-8) assay (expressed as absorbance A value). Expression levels of glutathione peroxidase 4 (GPX4) protein in both skeletal muscle tissue and L6 cells were evaluated by immunofluorescence staining and Western blot, respectively.Results:After 18 hours of in vitro preservation of rat isolated amputated limbs, the following results were obtained: (1) HE staining results showed that the muscle fiber morphology of the modified UW solution perfusion group was close to that of the blank control group. Moreover, the area ratio of skeletal muscle cells in the modified UW solution perfusion group was significantly higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). (2) The wet-dry weight ratio results showed that there was no statistically significant difference among the modified UW solution perfusion group, the blank control group and UW solution group ( P>0.05), with significantly lower ratios in all three groups than that in the hypothermic storage group ( P<0.05). (3) Transmission electron microscopy results revealed that the modified UW solution perfusion group showed no statistically significant differences in ultrastructural metrics, including myofiber diameter, sarcomere length, mitochondrial short-axis/long-axis ratio, and mitochondrial cristae count, compared with those in the blank control group ( P>0.05), and performed significantly better than both the hypothermic storage group and UW solution perfusion group ( P<0.05). (4) Morphological observation of L6 cells showed that the cellular morphology was regular in the modified UW solution perfusion group, close to that in the blank control group, while it was severely damaged in the hypothermic storage group. Moreover, the cells were reduced in number and partially damaged in the UW solution group. The sequence of cell viability expressed as absorbance A value was blank control group >modified UW solution perfusion group > UW solution perfusion group > hypothermic storage group, with statistically significant differences among the four groups ( P<0.05). (5) Immunofluorescence staining showed that there was no statistically significant difference in fluorescence intensity of GPX4 protein expression between the modified UW solution perfusion group and blank control group ( P>0.05), while the fluorescence intensity was higher in the modified UW solution perfusion group than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Western blot analysis showed that the relative expression level of GPX4 in the modified UW solution group was significantly lower than that in the blank control group ( P<0.05), but higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Conclusion:The modified UW solution can stabilize the expression level of GPX4 protein, thereby inhibiting ferroptosis and alleviating cold preservation injury in both rat amputated isolated limb skeletal muscle tissue and L6 cells.

Objective To explore the sex differences in drug metabolism of sufentanil in Chinese patients based on the mutation classification of cytochrome P450 3A(CYP3A)enzymes.Methods According to the possible effects of combined cytochrome P450 3A4 gene*1G locus(CYP3A4*1G)and cytochrome P450 3A5 gene*3 locus(CYP3A5*3)mutation groups on Chinese population,we added different weights to CYP3A4*1G and CYP3A5*3 polymorphisms and classified patients into 3 groups:GroupⅠ,patients carried either the CYP3A4*1G/*1G allele or both CYP3A4*1/*1G allele and CYP3A5*3/*3 allele;Group Ⅱ,patients with both CYP3A4*1/*1G allele and CYP3A5*1/*3 allele;Group Ⅲ,patients with either the CYP3A4*1/*1 allele or both CYP3A4*1/*1G allele and CYP3A5*1/*1 allele.A single-dose,double-blind,stratified random sampling was performed,and 255 patients undergoing endoscopic surgery in the First Affiliated Hospital of Army Medical University were finally subjected.According to the results of genetic testing,an independent statistician,before operation,randomly selected 30 patients from each stratified group to form a study cohort(male-female ratio of 1∶1)and named each group A,B or C.Clinical investigators and subjects kept double-blind to the results of grouping and genetic testing.After entering the operating room,the subjected 90 patients received a single dose of sufentanil followed by collection of blood samples at 10 time points including 2 min before and from 2 to 120 min after administration.After the surgery,we determined the plasma drug concentration,calculated the pharmacokinetic parameters,and compared the metabolic differences between different genders in each group and unblinded the study.Results The cohort best fitted the two-compartment pharmacokinetic model,and groups A,B and C corresponded to group Ⅰ,Ⅱand Ⅲ,respectively.In different patient groups based on mutatron types of CYP3A enzymes the females had lower plasma drug concentration-time curves at each time point,higher systemic clearance(P≤0.01)and smaller area under the plasma concentration-time curve from zero to infinity(P＜0.05)when compared with the males.In addition,in group Ⅰ,the elimination rate of central compartment and movement rate of drug from central compartment to peripheral compartment were obviously greater in the females than the males(P＜0.05),while the distribution half-life(P＜0.05)and elimination half-life(P＜0.01)were notably longer in the males than the females.In both group Ⅱ and group Ⅲ,the males obtained larger total area under the plasma concentration-time curve than the females(P＜0.05).Conclusion There are sex differences in the drug metabolism of sufentanil in Chinese patients.Women show faster distribution and higher clearance of sufentanil while men present greater drug exposure.Preoperative CYP3A genotyping and intraoperative personalized medication are of great significance to ensure the safety in clinical practice.

Objective To explore the pharmacokinetic characteristics of sufentanil in individuals with normal body mass index(BMI),overweight BMI,and different CYP3A4/5 enzyme genotypes.Methods The patients receiving laparoscopic surgery under general anesthesia in the First Affiliated Hospital of Army Medical University from November 2020 to September 2021 were prospectively recruited in this study.Before the operation,the oral swabs were collected from all the patients for genotyping using the human CYP3A4/5 gene kit.Based on the potential impact of combination of their polymorphisms on sufentanil metabolism and the proportion of different genotype combinations of CYP3A4/5 enzymes,the patients were divided into groups I(3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation),II(3A4 heterozygous mutation+3A5 heterozygous mutation),and III(3A4 wild type or 3A4 heterozygous mutation+3A5 wild type).According to their BMI,they were also assigned into a normal body weight group(18.5～24.0 kg/m2)and an overweight group(24～<28 kg/m2),and the differences in drug metabolism parameters were statistically analyze between the 2 groups.After routine general anesthesia induction(sufentanil 0.5 μg/kg),venous blood samples were collected to detect the changes in its concentration using high performance liquid chromatography-mass spectrometry(HPLC-MS).The pharmacokinetic data of sufentanil were calculated between the normal BMI group and overweight group in all participants and between the 2 body weight groups among those with different genotype combinations.Results Among the 90 participants completing the blood drug concentration test,8 patients had their blood samples contaminated(including 1 case with an anesthesia duration of<2 h),and 3 were excluded due to low weight or overweight.Eventually,79 participants were included in the pharmacokinetic analysis on the normal body weight group and the overweight group.Compared with the normal body weight group,the central compartment volume of distribution in the overweight group was significantly reduced(P<0.05),while no obvious differences were observed between the 2 groups in terms of peripheral compartment volume of distribution,total clearance rate,peripheral compartment clearance rate,distribution half-life,clearance half-life,and area under the blood concentration-time curve.In group Ⅰ(n=26),the overweight patients(n=13)had significantly reduced central compartment volume of distribution,peripheral compartment volume of distribution,and peripheral compartment clearance rate when compared with the normal body weight patients(n=13)(P<0.05),while no differences were observed in other pharmacokinetic parameters.In groups Ⅱ(n=25)and Ⅲ(n=28),the overweight patients and normal body weight patients had no statistical differences in all pharmacokinetic parameters.Conclusion Among the patients with the same genotype combination of CYP3A4/5 mutations,there was no difference in the metabolism of sufentanil between the overweight and normal weight patients.Additionally,in the population of 3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation,the overweight patients have smaller peripheral distribution range of sufentanil,and weakened metabolic process.

Objective To examine the causes of incision infections following lower extremity open fractures and develop a predictive model for assessing the risk.Methods A total of 104 patients with open fractures of the lower extremity,who received internal fixation from January 2022 to August 2023.According to whether there was incision infection after the operation,the patients were divided into infection group and non-infection group.The aim of the study was to analyze the distribution of pathogenic bacteria causing postoperative incision infections.Single-factor and multifactor Logistic regression analyses were employed to examine the factors influencing postoperative incisional infections.Subsequently,a risk prediction model for these infections was developed.The predictive capacity of this model was assessed using ROC curves.Results In the cohort of 104 patients with open fractures of the lower limb,the occurrence rate of postoperative incision infections was 19.23％.A total of 45 non-repeated pathogenic bacteria were isolated,among which gram-positive bacteria accounted for 53.33％,gram-negative bacteria 42.22％,fungi 4.44％.Gram-positive bacteria showed 100％resistance to ampicillin/sulbactam and penicillin,while resistance rates for erythromycin and clindamycin exceeded 90％.Among gram-negative bacteria,resistance rates to cefazolin,sulfamethoxazole/trimethoprim,levofloxacin,ampicillin/sulbactam,ciprofloxacin,and gentamicin were all above 67％.Notably,resistance rates for cefazolin,sulfamethoxazole,and trimethoprim surpassed 90％.Univariate and multifactorial logistic stepwise regression analysis highlighted that time elapsed from injury to surgery,duration of surgery,length of hospital stay,perioperative prophylactic medication,and Gustilo classification were significant risk factors for postoperative incisional infections in patients with the condition(P＜0.05).The ROC curves illustrated that the risk prediction model accurately forecasted the incidence of postoperative incisional infections in patients with open fractures of the lower extremity,with an area under the curve of 0.861(95％ CI:0.811 to 0.911),boasting a sensitivity of 90.50％and a specificity of 72.92％.Conclusion The main pathogen of wound infection after open fracture of lower extremity is Gram-negative,the time from injury to operation,operation time,hospitalization time,prophylactic medication during perioperative period and GUSTILO classification were the influencing factors of postoperative wound infection.In addition,the establishment of risk prediction model has a good prediction effect on the incidence of postoperative wound infection in patients with this disease.

Objective To examine the causes of incision infections following lower extremity open fractures and develop a predictive model for assessing the risk.Methods A total of 104 patients with open fractures of the lower extremity,who received internal fixation from January 2022 to August 2023.According to whether there was incision infection after the operation,the patients were divided into infection group and non-infection group.The aim of the study was to analyze the distribution of pathogenic bacteria causing postoperative incision infections.Single-factor and multifactor Logistic regression analyses were employed to examine the factors influencing postoperative incisional infections.Subsequently,a risk prediction model for these infections was developed.The predictive capacity of this model was assessed using ROC curves.Results In the cohort of 104 patients with open fractures of the lower limb,the occurrence rate of postoperative incision infections was 19.23％.A total of 45 non-repeated pathogenic bacteria were isolated,among which gram-positive bacteria accounted for 53.33％,gram-negative bacteria 42.22％,fungi 4.44％.Gram-positive bacteria showed 100％resistance to ampicillin/sulbactam and penicillin,while resistance rates for erythromycin and clindamycin exceeded 90％.Among gram-negative bacteria,resistance rates to cefazolin,sulfamethoxazole/trimethoprim,levofloxacin,ampicillin/sulbactam,ciprofloxacin,and gentamicin were all above 67％.Notably,resistance rates for cefazolin,sulfamethoxazole,and trimethoprim surpassed 90％.Univariate and multifactorial logistic stepwise regression analysis highlighted that time elapsed from injury to surgery,duration of surgery,length of hospital stay,perioperative prophylactic medication,and Gustilo classification were significant risk factors for postoperative incisional infections in patients with the condition(P＜0.05).The ROC curves illustrated that the risk prediction model accurately forecasted the incidence of postoperative incisional infections in patients with open fractures of the lower extremity,with an area under the curve of 0.861(95％ CI:0.811 to 0.911),boasting a sensitivity of 90.50％and a specificity of 72.92％.Conclusion The main pathogen of wound infection after open fracture of lower extremity is Gram-negative,the time from injury to operation,operation time,hospitalization time,prophylactic medication during perioperative period and GUSTILO classification were the influencing factors of postoperative wound infection.In addition,the establishment of risk prediction model has a good prediction effect on the incidence of postoperative wound infection in patients with this disease.

Objective:To develop a modified University of Wisconsin preservation solution (UW solution) containing α 2-adrenergic receptor agonists (dexmedetomidine) and noble gases (argon) and investigate its protective effect on the isolated amputated skeletal muscle of rats. Methods:Sixty male SD rats were selected to establish a hindlimb cold preservation/perfusion model and were divided into blank control group, hypothermic storage group, UW solution perfusion group, and modified UW solution perfusion group using a random number table, with 15 rats in each group. Simultaneously, a cold preservation model of rat skeletal muscle myoblasts (L6 cells) was established and the rats were also divided into four groups in the same way. Animal models were prepared in different ways: In the blank control group, the hindlimbs received no special treatment; In the hypothermic storage group, the amputated hindlimbs were stored in a dry centrifuge tube at 4℃ for 18 hours; In the UW solution perfusion group, the amputated hindlimbs were perfused with UW solution and then stored in a centrifuge tube containing UW solution at 4℃ for 18 hours; In the modified UW solution perfusion group, the amputated hindlimbs were perfused with modified UW solution (containing 0.1 nmol/L dexmedetomidine and 50% volume fraction of argon) and then stored in a centrifuge tube containing the modified UW solution at 4℃ for 18 hours. Cell models were treated as follows: In the blank control group, L6 cells were cultured under standard conditions; In the hypothermic storage group and UW solution group, L6 cells were treated with conventional culture medium or UW solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours; In the modified UW solution group, L6 cells were treated with the modified solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours. After sample collection, skeletal muscle morphology, tissue edema and ultrastructure features were assessed by HE staining, wet-to-dry weight ratio, and transmission electron microscopy, respectively. Additionally, L6 cell morphology was examined by light microscopy. L6 cell viability was determined by cell counting kit-8 (CCK-8) assay (expressed as absorbance A value). Expression levels of glutathione peroxidase 4 (GPX4) protein in both skeletal muscle tissue and L6 cells were evaluated by immunofluorescence staining and Western blot, respectively.Results:After 18 hours of in vitro preservation of rat isolated amputated limbs, the following results were obtained: (1) HE staining results showed that the muscle fiber morphology of the modified UW solution perfusion group was close to that of the blank control group. Moreover, the area ratio of skeletal muscle cells in the modified UW solution perfusion group was significantly higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). (2) The wet-dry weight ratio results showed that there was no statistically significant difference among the modified UW solution perfusion group, the blank control group and UW solution group ( P>0.05), with significantly lower ratios in all three groups than that in the hypothermic storage group ( P<0.05). (3) Transmission electron microscopy results revealed that the modified UW solution perfusion group showed no statistically significant differences in ultrastructural metrics, including myofiber diameter, sarcomere length, mitochondrial short-axis/long-axis ratio, and mitochondrial cristae count, compared with those in the blank control group ( P>0.05), and performed significantly better than both the hypothermic storage group and UW solution perfusion group ( P<0.05). (4) Morphological observation of L6 cells showed that the cellular morphology was regular in the modified UW solution perfusion group, close to that in the blank control group, while it was severely damaged in the hypothermic storage group. Moreover, the cells were reduced in number and partially damaged in the UW solution group. The sequence of cell viability expressed as absorbance A value was blank control group >modified UW solution perfusion group > UW solution perfusion group > hypothermic storage group, with statistically significant differences among the four groups ( P<0.05). (5) Immunofluorescence staining showed that there was no statistically significant difference in fluorescence intensity of GPX4 protein expression between the modified UW solution perfusion group and blank control group ( P>0.05), while the fluorescence intensity was higher in the modified UW solution perfusion group than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Western blot analysis showed that the relative expression level of GPX4 in the modified UW solution group was significantly lower than that in the blank control group ( P<0.05), but higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Conclusion:The modified UW solution can stabilize the expression level of GPX4 protein, thereby inhibiting ferroptosis and alleviating cold preservation injury in both rat amputated isolated limb skeletal muscle tissue and L6 cells.

Objective To analyze the factors related to early allograft dysfunction(EAD)after liver transplantation and to construct a predictive model.Methods A total of 375 patients who underwent liver transplantation in our hospital from December 2008 to December 2021 were collected,including 90 patients with EAD and 266 patients without EAD.Thirty items of baseline data for the 2 groups were compared and analyzed.Aftergrouping in a ratio of 7∶3,univariate and multivariate logistic regression analyses were used in the training set to evaluate the factors related to EAD and construct a nomogram.Receiver operating characteristic(ROC)curve,decision curve analysis(DCA),sensitivity,specificity,positive predictive value,negative predictive value,Kappa value and other indicators were used to evaluate the model performance.Results The incidence of EAD after liver transplantation was 24%.Multivariate logistic regression analysis showed that preoperative tumor recurrence history(OR=3.15,95%CI:1.28～7.77,P=0.013)and operation time(OR=1.22,95%CI:1.04～1.42,P=0.015)were related to the occurrence of EAD after surgery.After predicting the outcome according to the cut-off point of 0.519 identified by the Youden index,the model performance in the both training set and validation set was acceptable.DCA suggested the model has good clinical applicability.Conclusion The risk factors for EAD after liver transplantation are preoperative tumor recurrence history and operation time,and the established model has predictive effect on prognosis.

OBJECTIVE:To investigate the characteristics and causes of cardiac ADR induced by quinolones,and to provide reference for clinical treatment. METHODS:Three thousaud two hundred and eighty-eighe 8 patients receiving common quinolones were selected from clinical departments in Zhengzhou Central Hospital of Zhengzhou University during Mar. 2012-Mar. 2016. Retro-spective analysis was conducted in terms of patients’age and gender,clinical departments,main clinical manifestations,route of administration,underlying disease,drug combination. The reasons for cardiac ADR were analyzed. RESULTS:Among 3 288 pa-tients,there were 34 patients(1.03%)with cardiac ADR. Among them,the incidence of cardiac ADR in patients over 50 years old was as high as 76.47%;patients with cardiac ADR were mainly in the respiration department,gastroenterology department and urology department,accounting for 76.47%;most of patients were from gastroenterology department(29.41%). In cardiac ADR, the main clinical manifestations were QTc interval prolongation torsadesde poiutes(TdP)and TdP,accounting for 58.82%. Among them,patients with QTc interval prolongation TdP occupied the highest proportion,there was no statistical significance compared to TdP(P>0.05);there was statistical significance in the difference with other clinical manifestations(P<0.05). Among common-ly used quinolones,levofloxacin(32.35%)and ciprofloxacin(41.18%)caused large proportion of cardiac ADR,there was statisti-cal significance compared to norfloxacin,moxifloxacin and other quinolones(P<0.05). The proportion of cardiac ADR induced by intravenous dripping(91.18%)was much higher than oral administration(8.82%),with statistical significance(P<0.05). Among patients with cardiac ADR,the patients with underlying disease (94.12%) and drug combination (91.18%) occupied the higher proportion,there was statistical significance compared to the patients without underlying disease and drug combination(P<0.01). Among drug combination,the patients receiving amiodarone (29.41%) and salbutamol (20.59%) occupied the large proportion, there was statistical significance compared to other types of drug combination(P<0.05). CONCLUSIONS:Cardiac ADR induced by quinolones in our hospital mostly occurs in respiration department,gastroenterology department and urology department,and mainly manifests as QTc interval prolongation TdP and TdP. The incidence of cardiac ADR may be greatly increased in elderly pa-tients,patients with underlying diseases,and drug combination as well as intravenous infusion. Therefore,clinicians should select suitable quinolones,and make reasonable individualized dosage regimen.

Objective:To evaluate the outcomes of lesser arc perilunate injuries (Perilunate disloca-tions)treated with arthroscopically assisted mini-invasive reduction and fixation.Methods:Between 2012 and 2014,5 patients who had a perilunate dislocation were treated with arthroscopically assisted re-duction and percutaneous fixation.The mean follow-up was 17.8 months (range,10 to 32 months). Clinical outcomes were evaluated on the basis of range of motion;grip strength;Mayo wrist score;Quick disabilities of the arm,shoulder and hand questionnaire;and patient-rated wrist evaluation score.Radio-graphic evaluations included carpal alignments and any development of arthritis.Results:The range of flexion-extension motion of injured wrist averaged 84% of the values for contralateral wrist.The grip strength of the injured wrist averaged 90% of the values for the contralateral wrists.The mean Quick Disabilities of the arm,shoulder and hand score was 1 ,and the mean Patient-Rated Wrist Evaluation score was 5 .According to the Mayo wrist scores,the overall functional outcomes were rated as excellent in all the patients.Reduction obtained during the operation was maintained within normal ranges in all the patients.Arthritis had not developed in any patient at the end of the follow-up.Conclusion:Arthroscopic mini-invasive reduction with percutaneous fixation is a reliable and favorable alternative in the treatment of perilunate dislocations according to our early results.