Objective To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine(MDMA)and its metabolite 4,5-methylene dioxy amphetamine(MDA)in rats af-ter single and continuous administration of MDMA,providing reference data for the forensic identifica-tion of MDMA.Methods A total of 24 rats in the single administration group were randomly divided into 5,10 and 20 mg/kg experimental groups and the control group,with 6 rats in each group.The ex-perimental group was given intraperitoneal injection of MDMA,and the control group was given intraperi-toneal injection of the same volume of normal saline as the experimental group.The amount of 0.5 mL blood was collected from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.In the continuous administration group,24 rats were randomly divided into the experi-mental group(18 rats)and the control group(6 rats).The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5,7,9,11,13,15,17 mg/kg per day,respectively,while the control group was given the same volume of normal saline as the experimental group by in-traperitoneal injection.On the eighth day,the experimental rats were randomly divided into 5,10 and 20 mg/kg dose groups,with 6 rats in each group.MDMA was injected intraperitoneally,and the con-trol group was injected intraperitoneally with the same volume of normal saline as the experimental group.On the eighth day,0.5 mL of blood was taken from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels,and statistical software was employed for data analysis.Results In the single-administration group,peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration,respectively,with the largest detection time limit of 12 h.In the continuous administration group,peak concentrations were reached at 30 min and 1.5 h af-ter administration,respectively,with the largest detection time limit of 10 h.Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows:T=10.362C-1.183,R2=0.974 6;T=7.397 3C-0.694,R2=0.961 5(T:injection time;C:concentration ratio of MDMA to MDA in plasma).Conclusions The toxicokinetic data of MDMA and its metabolite MDA in rats,obtained through single and continuous administration,including peak concentration,peak time,detection time limit,and the relationship between concentration ratio and administration time,provide a theoretical and data foundation for relevant forensic identification.

BACKGROUND:The stability of the pelvis is mainly determined by the posterior pelvic ring and the sacroiliac joint.The posterior pelvic ring injury and the dislocation of the sacroiliac joint caused by high energy impacts such as car accidents increase year by year.Surgical treatment is the best method,and there are many kinds of endophytorepair methods in clinical practice,but which treatment method has the best biomechanical properties is still controversial. OBJECTIVE:To compare the biomechanical properties of three kinds of internal implants:anterior double plates,posterior bridging plate and tension nail in the repair of unilateral unstable pelvic posterior ring injury,to provide a reference for the clinical treatment and development of a new pelvic tension screw. METHODS:(1)Finite element simulation:Mimics,Wrap and SolidWorks were used to establish normal pelvic model,unilateral injured pelvis model,and three kinds of internal implant repaired models(anterior double plates,posterior bridging plate and tension nail).Ansys was used to analyze the stress and deformation of the models.(2)Biomechanical test:A total of 15 intact pelvic specimens were randomly grouped into five groups,normal pelvic model,unilateral injured pelvis model,anterior double plates,posterior bridging plate and tension nail groups.The mechanical test was performed using an Instron E10000 testing machine. RESULTS AND CONCLUSION:(1)Simulation:In the normal pelvic model,the average displacement of the sacrum was 0.174 mm,and the maximum stress of the sacral iliac bone was 10.51 MPa,and the stress distribution was uniform.The mean sacral displacement of the unilateral injured pelvis model was 0.267 mm,and the stress concentration of the model was obvious.The mean displacement of the sacrum in the three repaired models was close to that in the normal pelvic model,and the stress distribution of the sacral iliac bone in the tension nail repaired model was uniform.(2)Mechanical test:The stiffness of the normal pelvic model was(226.38±4.18)N/mm,and that of the unilateral unstable pelvic model was the smallest(130.02±2.19)N/mm.The deviation of the normal pelvic model stiffness and the three repaired models'stiffness were all within(±10%),and the repair effect was obvious.(3)The simulation results were in agreement with the experimental results.(4)The biomechanics of the tension nail repaired model was the most similar to that of the normal pelvis,and this method was the best.The repairing stiffness of the anterior double plate was too large,and the stress shielding effect was more significant.The posterior bridging plate repair could not solve the compensatory effect of the normal side soft tissue and had defects.This study provides an optimal basis for clinical surgery.(5)The new type of pelvic tension nail should be improved from the point of view of the tension nail to retain the good biomechanical properties of the tension nail,while adding other advantages,such as being used for the osteoporotic pelvis.

Objective: To investigate the immune reconstitution of HIV/AIDS patients and its influencing factors after receiving antiviral therapy (ART) in Hangzhou City, so as to provide insights into improving the treatment effects and quality of life in HIV/AIDS patients. Methods: A retrospective cohort of HIV/AIDS patients who began antiviral treatment between January 1, 2016 and August 31, 2021 and had a baseline CD4+T lymphocyte (CD4) counts of less than 500 cells/μL or a baseline CD4/CD8+T lymphocyte (CD8) ratio of less than 0.8 in Hangzhou City was followed up until August 31, 2023. Demographic information, antiviral therapy in formation, CD4 counts, and CD4/CD8 were collected from the Chinese Disease Prevention and Control Information System. A good immune reconstitution was defined as having CD4≥500 cells/μL and CD4/CD8≥0.8. The immune reconstitution status of HIV/AIDS patients were analyzed, and factors affecting immune reconstitution were identified using a multivariable Cox proportional risk regression model. Results: A total of 3 349 HIV/AIDS patients were enrolled, with a median age at ART of 31 (interquartile range, 20) years. There were 3 075 males (91.82%), 1 600 cases with college education and above (47.78%) and 2 455 cases at WHO clinical stage Ⅰ-Ⅱ(73.31%). There were 1 368 cases with good immune reconstitution, accounting for 40.85%, and the proportion of HIV/AIDS patients with good immune reconstitution that began ART in 2016 was the highest, reaching 51.90%. Multivariable Cox proportional risk regression model identified WHO clinical stage (Ⅰ-Ⅱ, HR=2.529, 95%CI: 2.023-3.162), timely ART (HR=1.196, 95%CI: 1.027-1.394), initial treatment regimen (TDF+3TC+NVP/EFV, HR=2.185, 95%CI: 1.891-2.524; integrase inhibitors, HR=8.509, 95%CI: 6.706-10.795), baseline CD4/CD8 (≥0.1, HR: 1.600-4.515, 95%CI: 1.061-6.661), baseline hemoglobin (<90 mg/dL, HR=0.327, 95%CI: 0.121-0.880), hepatitis B infection (HR=0.619, 95%CI: 0.457-0.840) and hepatitis C infection (HR=0.308, 95%CI: 0.099-0.956) as factors affecting immune reconstitution in HIV/AIDS patients. Conclusion The immune reconstitution in HIV/AIDS patients after ART is associated with WHO clinical stage, timely ART, initial treatment regimen, baseline CD4/CD8, baseline hemoglobin and hepatitis B or C infection.

Objective:To investigate the surgical treatment effect and prognostic factors of hilar cholangiocarcinoma.Methods:This is an ambispective cohort study. From August 2005 to December 2022,data of 510 patients who diagnosed with hilar cholangiocarcinoma and underwent surgical resection at the Hepatobiliary Center of the First Affiliated Hospital of Nanjing Medical University were retrospectively collected. In the cohort,there were 324 males and 186 females,with an age of ( M (IQR)) 63(13)years (range:25 to 85 years). The liver function at admission was Child-Pugh A (343 cases,67.3%) and Child-Pugh B (167 cases,32.7%). Three hundred and seventy-two(72.9%) patients had jaundice symptoms and the median total bilirubin was 126.3(197.6) μmol/L(range: 5.4 to 722.8 μmol/L) at admission. Two hundred and fourty-seven cases (48.4%) were treated with percutaneous transhepatic cholangial drainage or endoscopic nasobiliary drainage before operation. The median bilirubin level in the drainage group decreased from 186.4 μmol/L to 85.5 μmol/L before operation. Multivariate Logistic regression was used to identify the influencing factors for R0 resection,and Cox regression was used to construct multivariate prediction models for overall survival(OS) and disease-free survival(DFS). Results:Among 510 patients who underwent surgical resection,Bismuth-Corlett type Ⅲ-Ⅳ patients accounted for 71.8%,among which 86.1% (315/366) underwent hemi-hepatectomy,while 81.9% (118/144) underwent extrahepatic biliary duct resection alone in Bismuch-Corlett type Ⅰ-Ⅱ patients. The median OS time was 22.8 months, and the OS rates at 1-,3-,5-and 10-year were 72.2%,35.6%,24.8% and 11.0%,respectively. The median DFS time was 15.2 months,and the DFS rates was 66.0%,32.4%,20.9% and 11.0%,respectively. The R0 resection rate was 64.5% (329/510), and the OS rates of patients with R0 resection at 1-,3-,5-and 10-year were 82.5%, 48.6%, 34.4%, 15.2%,respectively. The morbidity of Clavien-Dindo grade Ⅲ-Ⅴ complications was 26.1%(133/510) and the 30-day mortality was 4.3% (22/510). Multivariate Logistic regression indicated that Bismuth-Corlett type Ⅰ-Ⅲ ( P=0.009), hemi-hepatectomy and extended resection ( P=0.001),T1 and T2 patients without vascular invasion (T2 vs. T1: OR=1.43 (0.61-3.35), P=0.413;T3 vs. T1: OR=2.57 (1.03-6.41), P=0.010;T4 vs. T1, OR=3.77 (1.37-10.38), P<0.01) were more likely to obtain R0 resection. Preoperative bilirubin,Child-Pugh grade,tumor size,surgical margin,T stage,N stage,nerve infiltration and Edmondson grade were independent prognostic factors for OS and DFS of hilar cholangiocarcinoma patients without distant metastasis. Conclusions:Radical surgical resection is necessary to prolong the long-term survival of hilar cholangiocarcinoma patients. Hemi-hepatectomy and extended resection,regional lymph node dissection and combined vascular resection if necessary,can improve R0 resection rate.

Objective:To observe the clinical effect of free superficial temporal fascia flap combined with split thickness skin transplantation in repairing refractory wounds in the anterior tibia.Methods:Data on 19 patients with soft tissue defects in the anterior tibial region who were admitted to the First Affiliated Hospital of Air Force Medical University from September 2019 to October 2023 and met the inclusion criteria were collected and summarized. Among them, 11 were males and 8 were females, aged 19-70 years old. The wound area was 4.3 cm×5.0 cm-6.8 cm×9.5 cm, and all wounds were accompanied by tendon exposure. 5 patients also had local bone exposure, and 10 patients had varying degrees of local infection. All patients were treated with wound debridement and continuous closed negative pressure drainage to control infection. After controlling the wound infection, an equally large temporal superficial fascia tissue flap was designed and cut according to the size of the wound to repair the wound. At the same time, a scalp split thick skin was taken to cover the fascia flap.Results:All 19 patients with superficial temporal fascia flaps survived, while 2 patients had poor skin flap survival due to subcutaneous hematoma. After re-grafting, the wound healed. After follow-up for 6-24 months, all patients were satisfied with the appearance of the anterior tibial region and had good recovery of ankle joint function. The supply valve area was concealed, without obvious scars, hair loss, baldness and other complications.Conclusions:The use of free superficial temporal fascia flap combined with split thick skin transplantation for repairing anterior tibial wounds has the advantages of strong anti infection ability, thin fascia flap, concealed donor site, and reconstruction of supporting ligaments. It is an ideal repair method for repairing difficult to heal wounds in the anterior tibial area.

Objective:This study aimed to explore the status of radiological Kashin-Beck disease (KBD) among school-aged children in Chamdo City, Tibet, through a 3-year monitoring survey, providing epidemiological evidence for prevention and control strategies.Methods:The target areas for this study were Luolong, Bianba, and Basu counties in Chamdo City, Tibet Autonomous Region, identified as having the most severe historical cases of KBD. Children aged 7-12 years attending school were enrolled as study subjects. Anteroposterior X-ray films of the right-hand were taken, and radiological diagnoses were made based on the "Diagnosis of Kashin-Beck Disease" criteria (WS/T 207-2010). Two experienced researchers independently reviewed the X-rays, and intra- and inter-group consistency were assessed using weighted Kappa values and percentage agreement. Cross-sectional surveys were conducted in 2017 and 2020 to describe the X-ray detection rates of KBD, and logistic regression analysis was employed to construct a predictive model of risk factors for radiological KBD cases.Results:In 2017, a total of 5,711 children aged 7-12 years in Chamdo City, Tibet, participated in the baseline cross-sectional survey (average age 9.2 years, 48.0% female), with 28 cases of radiological KBD. The age- and gender-standardized prevalence rate was 0.527%. In 2020, 6,771 participants (average age 9.3 years, 49.5% female) underwent a second cross-sectional survey, with 9 cases of radiological KBD and a standardized prevalence rate of 0.134%. Logistic regression analysis indicated that older age [ OR=2.439, 95% CI(1.299, 4.580), P=0.006] and female gender [ OR=8.157, 95% CI(1.016, 65.528), P=0.048] were independent risk factors for radiological KBD cases. Conversely, higher residential altitude, under the premise of Tibet's high altitude, was a protective factor [ OR=0.995, 95% CI(0.990, 0.999), P=0.032). Conclusion:The radiographically positive detection rate of KBD among school-aged children in Chamdo City, Tibet Autonomous Region, is at an extremely low level and showing a declining trend, reaching the historical standard in 2020. Considering the absence of positive signs in affected children, it suggests that local KBD has been effectively eliminated.

Objective To compare the effect of three-dimensional visual (3DV) model, three-dimensional printing (3DP) model and computer-aided design (CAD) modified 3DP model in video-assisted thoracoscopic surgery (VATS) sublobular resection. Methods The clinical data of patients who underwent VATS sublobular resection in the Affiliated Hospital of Hebei University from November 2021 to August 2022 were retrospectively analyzed. The patients were divided into 3 groups including a 3DV group, a 3DP group and a CAD-3DP group according to the tools used. The perioperative indexes and subjective evaluation of operators, patients and their families were compared. Results A total of 22 patients were included. There were 5 males and 17 females aged 32-77 (56.95±12.50) years. There were 9 patients in the 3DV group, 6 patients in the 3DP group, and 7 patients in the CAD-3DP group. There was no statistical difference in the operation time, intraoperative blood loss, drainage volume, hospital stay time or postoperative complications among the groups (P>0.05). Based on the subjective evaluations of 4 surgeons, the CAD-3DP group was better than the 3DV group in the preoperative planning efficiency (P=0.025), intuitiveness (P=0.045) and doctor-patient communication difficulty (P=0.034); the CAD-3DP group was also better than the 3DP group in the overall satisfaction (P=0.023), preoperative planning difficulty (P=0.046) and efficiency (P=0.014). Based on the subjective evaluations of patients and their families, the CAD-3DP group was better than the 3DP group in helping understand the vessel around the tumor (P=0.016), surgical procedure (P=0.020), procedure selection (P=0.029), and overall satisfaction (P=0.048); the CAD-3DP group was better than the 3DV group in helping understand the tumor size (P=0.038). Conclusion CAD-modified 3DP model has certain advantages in pre-planning, intraoperative navigation and doctor-patient communication in the VATS sublobectomy.

In this study, plasma, urine and fecal samples were collected from rats after intragastric administration of novel insulin sensitizer Zg02 (20 mg·kg^-1). The ultra-performance liquid chromatography-quadrupole-time-of-flight-tandem mass spectrometry (UPLC-Q-TOF/MS^E) techniques was used to obtain the molecular ion and mass spectrometry fragment ion information of the compound, and the metabolites were quickly analyzed by combining with UNIFI metabolite software. The results showed that a total of 12 metabolites were inferred in rats after a single gavage of Zg02 (20 mg·kg^-1), including 5, 7 and 11 metabolites in plasma, urine and feces (including cross-analysis), and the metabolic pathways were mainly glucuronidation and glucosylation. All animal protocols were approved by the Animal Ethics Committee of Guizhou Medical University (No. 2100856).

This research established a simple, rapid and sensitive ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) method to investigate the metabolic profiles of cajanonic acid A (CAA) in rats. After intragastric administration of CAA (30 mg·kg^-1) to rats, the biological samples were detected by UPLC-Q-TOF-MS/MS. Relevant data was collected and processed, the accurate mass and MS² spectra of the metabolites were compared with the parent compound. As a result, a total of 23 metabolites were detected, including 15 in urine, 11 in bile, 11 in feces, and 9 in plasma. The major metabolic pathways related to CAA included dehydrogenation, reduction, hydroxylation, methylation and glucuronide conjugation. This experiment was approved by Animal Ethics Committee of Guizhou Medical University (approval number: 1603137).

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]