Suxiao Jiuxin Pills Prevent Ventricular Fibrillation from Inhibiting L-type Calcium Currents CaV1.2 in vivo and in vitro / 中国结合医学杂志

OBJECTIVE@#To investigate whether Suxiao Jiuxin Pills (SJP), a Chinese herbal remedy, is an anti-ventricular fibrillation (VF) agent.@*METHODS@#VF was induced by isoproterenolol (ISO) intraperitoneal injection followed by electrical pacing in mice and rabbits. The effects of SJP on the L-type calcium channel current (CaV1.2), voltage-dependent sodium channel current (INa), rapid and slow delayed rectifier potassium channel current (IKr and IKs, respectively) were studied by whole-cell patch-clamp method. Computer simulation was implemented to incorporate the experimental data of SJP effects on the CaV1.2 current into the action potential (AP) and pseudo-electrocardiography (pseudo-ECG) models.@*RESULTS@#SJP prevented VF induction and reduced VF durations significantly in mice and rabbits. Patch-clamp experiments revealed that SJP decreased the peak amplitude of the CaV1.2 current with a half maximal concentration (IC50) value of 16.9 mg/L (SJP-30 mg/L, -32.8 ± 6.1 pA; Verapamil, -16.2 ±1.8 pA; vs. control, -234.5 ±16.7 pA, P<0.01, respectively). The steady-state activation curve, inactivation curve, and the recovery from inactivation of the CaV1.2 current were not shifted significantly. Specifically, SJP did not altered INa, IKr, and IKs currents significantly (SJP vs. control, P>0.05). Computer simulation showed that SJP-reduced CaV1.2 current shortened the AP duration, transiting VF into sinus rhythm in pseudo-ECG.@*CONCLUSION@#SJP reduced VF via inhibiting the CaV1.2 current with in vivo, in vitro, and in silico studies, which provide experimental basis for SJP anti-VF clinical application.

Shexiang Tongxin Dropping Pill Allieviates Heart Failure via Extracellula Matrix-Receptor Interaction Pathways Based on RNA-Seq Transcriptomics and Experimental Studies / 中国结合医学杂志

OBJECTIVE@#To investigate the protective mechanisms of Chinese medicine Shexiang Tongxin Dropping Pills (STDP) on heart failure (HF).@*METHODS@#Isoproterenol (ISO)-induced HF rat model and angiotensin II (Ang II)-induced neonatal rat cardiac fibroblast (CFs) model were used in the present study. HF rats were treated with and without STDP (3 g/kg). RNA-seq was performed to identify differentially expressed genes (DEGs). Cardiac function was evaluated by echocardiography. Hematoxylin and eosin and Masson's stainings were taken to assess cardiac fibrosis. The levels of collagen I (Col I) and collagen III (Col III) were detected by immunohistochemical staining. CCK8 kit and transwell assay were implemented to test the CFs' proliferative and migratory activity, respectively. The protein expressions of α-smooth muscle actin (α-SMA), matrix metalloproteinase-2 (MMP-2), MMP-9, Col I, and Col III were detected by Western blotting.@*RESULTS@#The results of RNA-seq analysis showed that STDP exerted its pharmacological effects on HF via multiple signaling pathways, such as the extracellular matrix (ECM)-receptor interaction, cell cycle, and B cell receptor interaction. Results from in vivo experiments demonstrated that STDP treatment reversed declines in cardiac function, inhibiting myocardial fibrosis, and reversing increases in Col I and Col III expression levels in the hearts of HF rats. Moreover, STDP (6, 9 mg/mL) inhibited the proliferation and migration of CFs exposed to Ang II in vitro (P<0.05). The activation of collagen synthesis and myofibroblast generation were markedly suppressed by STDP, also the synthesis of MMP-2 and MMP-9, as well as ECM components Col I, Col III, and α-SMA were decreased in Ang II-induced neonatal rats' CFs.@*CONCLUSIONS@#STDP had anti-fibrotic effects in HF, which might be caused by the modulation of ECM-receptor interaction pathways. Through the management of cardiac fibrosis, STDP may be a compelling candidate for improving prognosis of HF.

Prokaryotic expression of a recombinant protein of adeno-associated virus capsid conserved regions and preparation of its polyclonal antibody / 南方医科大学学报

OBJECTIVE@#To express and purify the antigenic peptide of adeno-associated virus (AAV) capsid conserved regions in prokaryotic cells and prepare its rabbit polyclonal antibody.@*METHODS@#The DNA sequence encoding the conserved regions of AAV capsid protein was synthesized and cloned into the vector pET30a to obtain the plasmid pET30a-AAV-CR for prokaryotic expression and purification of the conserved peptides. Coomassie blue staining and Western blotting were used to identify the AAV conserved peptides. Japanese big ear white rabbits were immunized with AAV conserved region protein to prepare polyclonal antibody, with the rabbits injected with PBS as the control group. The antibody titer was determined with ELISA, and the performance of the antibody for recognizing capsid protein sequences of AAV1-AAV10 was assessed with Western blotting and immunofluorescence assay.@*RESULTS@#The plasmid pET30a-AAV-CR was successfully constructed, and a recombinant protein with a relative molecular mass of 17000 was obtained. The purified protein induced the production of antibodies against the conserved regions of AAV capsid in rabbits, and the titer of the purified antibodies reached 1:320 000. The antibodies were capable of recognizing a wide range of capsid protein sequences of AAV1-AAV10.@*CONCLUSION@#We successfully obtained the polyclonal antibodies against AAV capsid conserved region protein from rabbits, which facilitate future studies of AAV vector development and the biological functions of AAV.

Research progress on the relationship of overactive bladder syndrome and irritable bowel syndrome / 中国综合临床

Overactive bladder syndrome is a complex of lower urinary tract symptoms that disturbs people of all ages worldwide. The etiology and pathogenesis are unclear, and the treatment effect is often poor.In recent years, with the in-depth study of overactive bladder, it has been found that patients with overactive bladder are often accompanied by intestinal functional changes such as irritable bowel, which presents high comorbidities with irritable bowel syndrome. This article will discuss the relationship of overactive bladder and irritable bowel syndrome from three aspects of comorbidities,pathogenesis and treatment,in order to find similarities between overactive bladder and irritable bowel syndrome.It provides new clues and methods for the pathogenesis and treatment of overactive bladder and irritable bowel syndrome.

Practical value and thought on "co-regulation of body and mind" in treatment of post-stroke spasticity with acupuncture / 中国针灸

This paper reviews the application of "co-regulation of body and mind" of acupuncture for post-stroke spasticity. It is found that acupoints on the head and the back of the governor vessel, as well as Jiaji (Ex-B 2) points are mainly used for regulating the mind, and the local sites of spastic muscles and the points on the antagonistic muscles are for regulating the body specially. It is believed that regulating the mind should be integrated with regulating the body, while, the acupoint selection be associated with needling methods so as to fully achieve the "co-regulation of body and mind" and enhance the practical value of acupuncture for post-stroke spasticity. It is proposed that the classical anti-spastic needling techniques, such as huici (relaxing needling) and guanci (joint needling), should be more considered.

Kuanxiong Aerosol () in Treatment of Angina Pectoris: A Literature Review and Network Pharmacology / 中国结合医学杂志

Angina pectoris (AP) is the most common symptom of cardiovascular diseases, which seriously affects the quality of life in cardiovascular patients. Kuanxiong (KX) Aerosol (), a compound preparation that consists of 5 traditional Chinese medicines: Herba Asari , Rhizoma Alpiniae Officinarum, Lignum Santali Albi, Fructus Piperis Longi, and Borneolum, has been used in the treatment of AP for many years, exhibiting a significant curative effect and less side-effect. For the convenience and comprehensive understanding of KX Aerosol, this review systematically summarizes evidence on KX Aerosol in the treatment of AP including the pharmacological effects of its composition, clinical research, animal experiments, and network pharmacology prediction. Meanwhile, we highlight the research limitation of KX Aerosol at present. This review may guide the clinical application of KX Aerosol and further provide a reference for the research of AP.

Effect of Tongguan Capsules () on Restenosis after Coronary Stent Implantation: Study Protocol for A Randomized Controlled Trial / 中国结合医学杂志

BACKGROUND@#Although percutaneous coronary intervention (PCI) had become widely employed therapeutic procedure for coronary artery disease, stent restenosis limited the benefits of this revascularization and the question how to prevent such events remained unresolved. While numerous empirical observations suggested Tongguan Capsules (), a patented Chinese Medicine, could decrease frequency and duration of angina pectoris attacks, evidence supporting its efficacy on restenosis remained inadequate.@*OBJECTIVE@#This trial was designed to determine whether Tongguan Capsules would reduce restenosis rate in patients after successful stent implantation.@*METHODS@#Approximately 400 patients undergoing percutaneous coronary stent deployment were enrolled and randomized to control group or Tongguan Capsules (4.5 g/d) for 3 months. All patients received standard anti-platelet, anti-coagulation and lipid-decreasing treatments, concurrently. The primary clinical endpoint was the 12-month incidence of the major adverse cardiovascular events (defined as cardiac death, myocardial infarction, and recurrence of symptoms requiring additional revascularization). The angiographic end point was restenosis rate at 6 months.@*CONCLUSION@#This study would provide important evidence for the use of Tongguan Capsules in patients after stent implantation in combination with routine therapies, which may significantly reduce incidence of the restenosis so as to potentially improve the clinical outcomes. (registration number: ChiCTR-TRC- ChiCTR-IIR-17011407).

A new 9,19-cycloartane glycoside from Asplenium ruprechtii / 中国中药杂志

Chemical constituents of water extracts of Asplenium ruprechtii were investigated. Five compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC, and their structures were identified by various spectral analyses as aspleniumside G(1), trans-p-coumaric acid(2), trans-p-coumaric acid 4-O-β-D-glucoside(3), cis-p-coumaric acid 4-O-β-D-glucoside(4), and(E)-ferulic acid-4-O-β-D-glucoside(5). Among them, compound 1 is a new 9,19-cycloartane glycoside.

Effect of Dahuang Zhechong Pills combined with TACE on VEGF, MMP-2, TGF-β1 and immune function of patients with primary liver cancer (blood stasis and collaterals blocking type) / 中国中药杂志

To investigate the effects of Dahuang Zhechong Pills combined with hepatic arterial chemoembolization(TACE) on tumor index and immune function of patients with primary liver cancer(blood stasis and collaterals blocking type), observe its application values in treatment of such patients, and provide effective treatment means for this disease. From June 2019 to December 2019, 79 patients with confirmed primary liver cancer(blood stasis and collaterals blocking type) treated in Wenzhou Hospital of Traditional Chinese Medicine were included in this study, all of which were grouped with random number table method before inclusion in this study. 40 patients in the control group were treated with TACE, while 39 patients in the observation group were treated with Dahuang Zhechong Pills combined with TACE. The efficacy was compared between two groups after 4 weeks of treatment. The immune function indexes of serum CD4~+ cells, CD4~+/CD8~+, CD3~+ cells of the observation group were higher than those in control group after treatment(P<0.05), and tumor indexes such as serum alpha-fetoprotein(AFP), carbohydrate antigen 199(CA199) and glutamic-pyruvic transaminase(ALT), total bilirubin(TBiL) levels were lower than those in the control group, with statistically significant differences(P<0.05). Plasma vascular endothelial growth factor(VEGF), transforming growth factor-β1(TGF-β1), and matrix metalloprotei-nase-2(MMP-2) levels in the observation group were lower than those in the control group after treatment, with statistically significant differences(P<0.05). The total effective rate of the observation group was 87.18%, higher than 67.50% in the control group, and the benefit rate was 94.87% in the observation group, higher than 85.00% in the control group(P<0.05). The total incidence of adverse reactions such as bone marrow suppression, gastrointestinal reaction, fever, renal function injury and peripheral nerve injury in the observation group was 48.72%, lower than 82.50% in the control group, with statistically significant difference(P<0.05). In summary, the combination of Dahuang Zhechong Pills with TACE could improve immunity, protect liver function, and reduce the risk of metastasis and the incidence of adverse reactions from chemotherapy, so it is worth popularizing for patients with primary liver cancer(blood stasis and collaterals blocking type).

Relationship between daily physical activity and sleep quality among college students / 中国学校卫生

Objective@#To explore the relationship between daily physical activity and sleep quality among college students during COVID-19 epidemic, so as to provide scientific basis for improving physical health and sleep of college students.@*Methods@#A stratified random sampling method was used to select a total of 2 808 college students from two universities (one in each of sports and non sports categories) in Beijing, Tianjin, and Wuhan in March 2020. The Pittsburgh Sleep Quality Index scale and the Bouchard Physical Activity Diary were used to collect sleep status and sleep duration (SD), sedentary behavior (SED), low intensity physical activity (LPA), and moderate to vigorous physical activity (MVPA). The Mann Whitney U test or Kruskal Wallis test was used to analyze the variability of parameters among college students. Multiple Logistic regression was used to analyze the relationship between physical activity and sleep quality.@*Results@#During the epidemic, male students had higher MVPA times(0.5 h) than female students(0 h) ( Z =-4.21, P <0.01); students aged 18 and younger had higher SED times(11.1 h) than students aged 19 to 21 and older(9.3,10.3 h) ( F =7.90, P <0.05). The SED was higher for students living in urban, combined urban rural areas(10.5,9.5 h) than for their rural counterparts(9.5 h) ( F =9.56, 10.73, P <0.01). Sport majors had higher LPA and MVPA times(3.9, 1.0 h) than non sports majors(3.0,0 h) ( Z =-2.99, -4.73, P <0.01), and lower SED and sleep times(8.3,9.8 h) than non sports majors(11.1,11.1 h) ( Z =-4.73, -2.42, P <0.01). The LPA time of students with general sleep quality and sleep disorder was lower than that of students with good sleep quality ( F =7.67, P <0.05), and SED time was higher than that of students with good sleep quality ( F =8.62, P <0.05). After controlling for gender, age, place of residence, and specialty, multiple Logistic regression analysis showed that LPA time deficit was a risk factor for sleep quality ( OR =0.84, 95% CI =0.71-0.99, P <0.05).@*Conclusion@#During the COVID-19 epidemic period, college students generally suffer from excessive sedentary time and insufficient physical activity, which vary in sex, region and specialty. The overall sleep quality of students is not optimistic, and the lack of low intensity physical activity may increase the risk of sleep disorders.

Astragaloside IV Attenuates Polymicrobial Sepsis-Induced Cardiac Dysfunction in Rats via IKK/NF-κB Pathway / 中国结合医学杂志

OBJECTIVE@#To evaluate the protective effects of Astragaloside IV (AST) in a rat model of myocardial injury induced by cecal ligation and puncture (CLP).@*METHODS@#The model of sepsis-induced cardiac dysfunction was induced by CLP. Using a random number table, 50 specific pathogen free grade of Sprague Dawley rats were randomized into 5 groups: the sham group (sham), the model group (CLP, 18 h/72 h) and AST group (18 h/72 h). Except the sham group, the rats in other groups received CLP surgery to induce sepsis. CLP groups received intragastric administration with normal saline after CLP. AST groups received intragastric administration with AST solution (40 mg/kg) once a day. The levels of inflammatory mediators and oxidative stress markers in the serum of the septic rats were determined via enzyme-linked immunosorbent assay (ELISA) at different time point, such as interleukin 6 (IL-6), IL-10, high mobility group box-1 protein B1 (HMGB-1), superoxide dismutase (SOD), and malondialdehyde (MDA). Cardiac function was determined by echocardiography. Moreover, changes in myocardial pathology were evaluated using hematoxylin and eosin staining. The levels of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) were analysed to determine the status of CLP-induced myocardium. In addition, the apotosis of myocardial cells was analysed by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL). The protein levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), IκB kinase α (IKKα), nuclear factor kappa B p65 (NF-κB p65) were detected by Western blot analysis. Moreover, survival rate was investigated.@*RESULTS@#AST improved the survival rate of CLP-induced rats by up to 33.3% (P<0.05). The cardioprotective effect of AST was observed by increased ejection fraction, fractional shortening and left ventricular internal diameter in diastole respectively (P<0.01 or P<0.05). Subsequently, AST attenuated CLP-induced myocardial apoptosis and the ratio of Bcl-2/Bax in the myocardium, as well as the histological alterations of myocardium (P<0.01 or P<0.05); the generation of inflammatory cytokines (IL-6, IL-10, HMGB-1) and oxidative stress markers (SOD, MDA) in the serum was significantly alleviated (P<0.01 or P<0.05). On the other hand, AST markedly suppressed CLP-induced accumulation of IKK-α and NF-κB p65 subunit phosphorylation (P<0.01 or P<0.05).@*CONCLUSIONS@#AST plays a significant protective role in sepsis-induced cardiac dysfunction and survival outcome. The possible mechanism of cardioprotection is dependent on the activation of the IKK/NF-κB pathway in cardiomyocytes.

Efficacy and safety of leflunomide in treatment of Henoch-Sch?nlein purpura nephritis with nephrotic proteinuria in children / 中国小儿急救医学

Objective:To compare the efficacy and safety of leflunomide(LEF)to mycophenolate mofetil(MMF)and cyclophosphamide(CTX)in the treatment of Henoch-Sch?nlein purpura nephritis(HSPN)in children with nephrotic proteinuria.Methods:Thirty-nine children who were diagnosed as HSPN with nephrotic proteinuria were randomly divided into three groups: LEF group, MMF group and CTX group.Each group had 13 children.Proteinuria, hematuria, adverse effect and cost were followed up at 1, 3, 6 and 9 months of medication.Results:Proteinuria and hematuria were significantly decreased in each group at 1, 3, 6 and 9 months of medication.Compared to CTX group, proteinuria and hematuria in LEF group and MMF group were lower at 9 months.It was probably associated with one child whose proteinuria did not completely return to normal at 9 months and another child who suffered from a relapse of proteinuria and hematuria at 6.5 months in CTX group.The results suggested that the efficacy of LEF and MMF was slightly better than CTX.During the observation period, all children were well tolerated and no serious adverse reactions occurred.One case showed a slight increase of alanine aminotransferase at 1 month, and returned to normal range at 3 months without any medication in MMF group.The cost of LEF group was(8 231±665)RMB and CTX group was(11 523±469)RMB which was significantly lower than(19 953±386)RMB in MMF group.Conclusion:LEF is as effective as MMF and CTX in the treatment of HSPN with nephrotic proteinuria in children.The adverse reactions of LEF are mild, and the cost is cheaper.LEF is worth popularizing in clinical practice.

Treatment analysis and pharmaceutical care for one child with bacterial meningitis / 药学实践杂志

Objective To explore the strategies of drug treatment and pharmaceutical care for children with bacterial meningitis. Methods The anti-infective therapy, therapeutic drug monitoring and dose adjustment of vancomycin in children with bacterial meningitis were analyzed and discussed according to relevant guidelines and literatures. Results Clinical pharmacists analyzed therapeutic regimen. According to the results of etiology and drug sensitivity, meropenem was discontinued and rifampicin was added. Based on drug monitoring of vancomycin, it is suggested to extend the infusion time of vancomycin to reach the target concentration. The child was discharged from hospital. Conclusion Recommendations of the relevant drug treatment guidelines and the latest medical research evidence should be provided by clinical pharmacists in order to promote reasonable and effective clinical uses of medicine.

Biomechanical evaluation of a novel transtibial posterior cruciate ligament reconstruction using high-strength sutures in a porcine bone model / 中华医学杂志(英文版)

BACKGROUND@#Multiple techniques are commonly used for posterior cruciate ligament (PCL) reconstruction. However, the optimum method regarding the fixation of PCL reconstruction after PCL tears remains debatable. The purpose of this study was to compare the biomechanical properties among three different tibial fixation procedures for transtibial single-bundle PCL reconstruction.@*METHODS@#Thirty-six porcine tibias and porcine extensor tendons were randomized into three fixation study groups: the interference screw fixation (IS) group, the transtibial tubercle fixation (TTF) group, and TTF + IS group (n = 12 in each group). The structural properties of the three fixation groups were tested under cyclic loading and load-to-failure. The slippage after the cyclic loading test and the stiffness and ultimate failure load after load-to-failure testing were recorded.@*RESULTS@#After 1000 cycles of cyclic testing, no significant difference was observed in graft slippage among the three groups. For load-to-failure testing, the TTF + IS group showed a higher ultimate failure load than the TTF group and the IS group (876.34 ± 58.78 N vs. 660.92 ± 77.74 N [P < 0.001] vs. 556.49 ± 65.33 N [P < 0.001]). The stiffness in the TTF group was significantly lower than that in the IS group and the TTF + IS group (92.77 ± 20.16 N/mm in the TTF group vs. 120.27 ± 15.66 N/m in the IS group [P = 0.001] and 131.79 ± 17.95 N/mm in the TTF + IS group [P < 0.001]). No significant difference in the mean stiffness was found between the IS group and the TTF + IS group (P = 0.127).@*CONCLUSIONS@#In this biomechanical study, supplementary fixation with transtibial tubercle sutures increased the ultimate failure load during load-to-failure testing for PCL reconstruction.

Clinical Practice Guideline of Integrative Chinese and Western Medicine for Acute Myocardial Infarction / 中国结合医学杂志

With increasing morbidity and mortality, acute myocardial infarction (AMI) has become one of the major causes of human death, leading to heavy burdens to individuals, families and society. Previous researches have found that though large amount of resources and great effort were devoted, no significant improvements were achieved in reducing the in-hospital mortality of AMI patients. Meanwhile, extensive studies about Chinese medicine (CM) have found that CM has special advantages in treating AMI patients. However, there is no standardized and unified clinical practice guideline (CPG) of CM for AMI. Therefore, a CPG with strict standard and generally acknowledgement is urgent to be established. This guideline was developed following the methodological process established by the World Health Organization Handbook for Guideline Development. Extensive search on clinical evidences including systematic review (SR), randomized controlled trial (RCT), observational study and case reports was launched, covering evidence of CM for AMI on several aspects, such as diagnosis, CM patterns, CM interventions on AMI and complications, cardiac rehabilitation and clinical pathway management. Besides, the application of Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach enabled the evaluation of evidence and formulation of grade of recommendation (GOR) and level of evidence (LOE). With the help of GOR and LOE, this CPG recommends the integrative CM and WM treatment method in AMI patients and provides useful information on medical decision for clinical physicians.

Protective Mechanisms of Suxiao Jiuxin Pills () on Myocardial Ischemia-Reperfusion Injury in vivo and in vitro / 中国结合医学杂志

OBJECTIVE@#To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills (, SXJ) on myocardial ischemia and reperfusion (I/R) injury.@*METHODS@#Mouse myocardial I/R injury model was created by 30-min coronary artery occlusion followed by 24-h reperfusion, the mice were then divided into the sham group (n=7), the I/R group (n=13), the tirofiban group (TIR, positive drug treatment, n=9), and the SXJ group (n=11). Infarct size (IS), risk region (RR), and left ventricle (LV) were analyzed with double staining methods. In addition, H9C2 rat cardiomyocytes were cultured with NaSO to simulate I/R in vitro. The phosphorylation of extracellular regulated protein kinases1/2 (ERK1/2), protein kinase B (AKT), glycogen synthase kinase-3β (GSK3β), and protein expression of GATA4 in nucleus were detected with Western blot assay.@*RESULTS@#The ratio of IS/RR in SXJ and TIR groups were lower than that in I/R group (SXJ, 22.4% ±6.6%; TIR, 20.8%±3.3%; vs. I/R, 35.4%±3.7%, P<0.05, respectively). In vitro experiments showed that SXJ increased the NaSO-enhanced phosphorylation of AKT/GSK3β and nuclear expression of GATA4.@*CONCLUSION@#SXJ prevents myocardial I/R injury in mice by activating AKT/GSK3β and GATA4 signaling pathways.

Application of PDCA cycle on improving the anesthesia teacher training / 中华医学教育探索杂志

Nowadays, PDCA circle is a widely used theory of quality management system. Through the PDCA approach, the management reform was conducted in 17 anesthesia teachers of the Anesthesiology department. After 18 months of training and promotion, the problems such as lack of enthusiasm for teaching, uneven level of teachers, and boring single teaching method were basically solved, which improved their teaching skills. Certain effectiveness has been achieved in teacher training management including continuity of quality management, timely feedback and emphatically improvement, student-center teaching philosophy, and mutual promotion of teaching and learning.

Relationship between the Degeneration and Regeneration of Neuromuscular Junction and Wound Age during the Repair of Mouse Skeletal Muscle Contusion / 法医学杂志

Objective To investigate the morphological changes in the degeneration and regeneration of neuromuscular junctions （NMJ） during the repair of mouse skeletal muscle contusion and discuss the correlation between the degeneration and regeneration of NMJ and wound age. Methods A total of 50 healthy adult male mice were randomly divided into 10 groups, including 9 experimental groups and 1 control group. Immunofluorescent staining was applied, and neurofilament was marked with neurofilament protein-H （NF-H）, presynaptic membrane was marked with synaptophysin （Syn）, presynaptic membrane was marked with acetylcholine receptor （AChR）. Morphological changes of NMJ regeneration at different time points after mouse skeletal muscle contusion were detected. Results The neurofilament and presynaptic membrane of NMJ at the junction of contusion zones began to degrade after contusion, and completed degradation at about 3 d post-injury. Then they gradually regenerated, roughly completing the regeneration at about 21 d and basically reaching the control group level. The ratio of presynaptic membrane quantity to presynaptic membrane quantity showed a trend of decreasing then rising and finally reaching the control level. Conclusion During the repair of mouse skeletal muscle contusion, the morphological changes and wound age of the NMJ at the junction of contusion zones have a close correlation, which is expected to be one of the biological indicators for forensic skeletal muscle wound age estimation.

Relationship between Changes of Pericyte Number and Wound Age during Repair of Skeletal Muscle Contusion in Mice / 法医学杂志

Objective To observe the change pattern of pericyte number at different time periods after mice skeletal muscle contusion and discuss its role in wound age estimation. Methods A mice gastrocnemius muscle contusion model was established. The form and number changes of pericytes at 1, 3, 5, 7, 9, 14, and 28 d post-injury were detected by multiple immunofluorescence staining. Results Compared with the slender shape of pericytes in normal skeletal muscles, pericytes in the contusion area had increased volume, rounder form and a round nuclei. Part of pericytes were found to express satellite cell markers paired-box transcription factor （Pax7） or myoblast determination 1 （MyoD1）. The changes of pericyte number in skeletal muscles after contusion were time-dependant, and showed unimodal distribution with the extension of wound age. In the central contusion area, the number of pericytes peaked at 5 d post-injury while in the peripheral contusion area, the number of pericytes peaked at 5 d and 7 d post-injury. Conclusion The number of pericytes in contusion area varies time-dependently after skeletal muscle contusion in mice and might be a reference index for muscle wound age estimation, and is involved in the repair and regeneration of skeletal muscle injury.

Relationship between Expression Changes of CB2R and Wound Age of Brain Contusion in Mice / 法医学杂志

Objective To investigate the expression of cannabinoid type 2 receptor （CB2R） at different time points after brain contusion and its relationship with wound age of mice. Methods A mouse brain contusion model was established with PCI3000 Precision Cortical Impactor. Expression changes of CB2R around the injured area were detected with immunohistochemical staining, immunofluorescent staining and Western blotting at different time points. Results Immunohistochemical staining results showed that only a few cells in the cerebral cortex of the sham operated group had CB2R positive expression. The ratio of CB2R positive cells gradually increased after injury and reached the peak twice at 12 h and 7 d post-injury, followed by a decrease to the normal level 28 d post-injury. The results of Western blotting were consistent with the immunohistochemical staining results. Immunofluorescent staining demonstrated that the changes of the ratio of CB2R positive cells in neurons, CB2R positive cells in monocytes and CB2R positive cells in astrocytes to the total cell number showed a single peak pattern, which peaked at 12 h, 1 d and 7 d post-injury, respectively. Conclusion The expression of CB2R after brain contusion in neurons, monocytes and astrocytes in mice suggests that it is likely to be involved in the regulation of the biological functions of those cells. The changes in CB2R are time-dependent, which suggests its potential applicability as a biological indicator for wound age estimation of brain contusion in forensic practice.