Adeno-associated virus(AAV)is a member of the parvovirus family,single-stranded DNA-containing nonenveloped icosahedral viruses.AAVs have been regarded as promising vectors for human gene therapy as they have the capacity to establish long-term latency within human cells without any apparent pathogenicity.However,a lot of obvious defects in their applications have been revealed recently,including the paucity of cell surface receptors on some cells,the lack of site-specific integration by recombinant AAV vectors,and the host immune responses to AAV capsid components and transgene products and so forth.Driven by these defects,increasing efforts are being made to study biological properties and infectious pathway of AAVs.It is consequently optimized by the modification of the AAV vectors to produce new generation of recombinant AAV vectors with more security,efficiency and site-specific targeting,allowing AAVs to move forward into broader clinical application.

Objective: To investigate surface electromyography signal (sEMG) of the major back muscle group and subjective fatigue assessment under different experimental combinations during walk with weight on both shoulders, as well as the functional status and fatigue property of human muscles. Methods: From October to December, 2017, 10 college students were recruited to participate in shoulder weight-bearing work and walk under the combinations of different shoulder strap widths, weights, and hardness of waist cushion. The subjects were required to complete 12 sets of experiments, with each set lasting for 15 minutes, and the rest time between work was 30 minutes. The sEMG signals of the upper trapezius and the erector spinae were measured during the experiment, and subjective fatigue assessment was performed during rest. The time domain evaluation index (average amplitude, aEMG) , the frequency domain evaluation index (median frequency, MF) , and the data of subjective assessment were processed and analyzed. Results: Weight and shoulder strap width had a significantly effect on fatigue (P<0.01) , and the change in the hardness of waist cushion had no significant effect on fatigue (P>0.05) . There was an interaction effect between weight and shoulder strap width (P<0.01) , and there was no interaction effect between weight, shoulder strap width, and hardness of waist cushion (P>0.05) . For the backpack carrying system, the combination of 10% weight and 50 mm shoulder strap width was the best one for relieving fatigue. The subjective test also showed that subjective feelings of muscle fatigue were associated with the weight and width, which was consistent with sEMG results. Conclusion The results of this experiment show that the combination of 10% weight and 50 mm shoulder strap width can help to relieve muscle fatigue during walk with weight on both shoulders, and weight-bearing walking is more likely to cause the fatigue of the erector spinae.

Objective: To summarize the mid-term effect of modified extended Morrow procedure in patients with hypertrophic obstructive cardiomyopathy (HOCM) combining sub aortic valve obstruction and mid left ventricular obstruction. Methods: We studied 34 consecutive HOCM patients with sub aortic and midventricular obstruction who received modiifed extended Morrow procedure with extracorporeal circulation in our hospital from 1996-11 to 2015-01. Transthoracic echocardiography was conducted at pre-, post-operation and follow-up period to evaluate the changes of mid-ventricular gradient, subarctic gradient and each heart valve function. Results: The average follow-up time was (25.7 ± 14.9) months, 2 patients lost contact and no death occurred. In rest 32 patients, the mid ventricular gradient decreased from (60.3 ± 29.4) mmHg to (21.0 ± 19.8) mmHg, subaortic valve gradient decreased from (77.9 ± 26.2) mmHg to (11.6 ± 6.5) mmHg, the maximum ventricular septal thickness dropped from (25.2 ± 4.9) mm to (17.9 ± 7.2) mm, left atrial diameter reduced from (41.1 ± 7.8) mm to (37.6 ± 6.4) mm, left ventricular end-diastolic diameter increased from (39.8 ± 5.1) mm to (42.2 ± 4.3) mm, allP<0.05; there were 5 patients without obviously improved mid ventricular gradient because of insufifcient resection of septal myocardium in mid-ventricle. The post-operative NYHA classiifcation was improved,P<0.01, mitral valve regurgitation degree was decreased,P<0.01 and SAM phenomenon was disappeared. Complications included 3 (8.8%) patients of III atrio-ventricular block, 1 (2.9%) patient of re-admission due to poorly healed sternum combining pneumonia Conclusion: Modified extended Morrow procedure may relieve sub aortic valve and mid ventricular obstruction, therefore improve left ventricular diastolic function and prognosis in relevant patients.

Objectives To investigate the expression and clinical significance of BATF2 in the oral tongue squamous cell carcinoma(OTSCC).Methods Expression of BATF2 mRNA and protein in 16 paired OTSCC tissues and adjacent non-tumor mucosa were examined using quantitative PCR,western blotting analysis and immunohistochemistry assays,and the relation between BATF2 expression and clinical pathologic factor and prognosis was analyzed.Results In 16 paired tissues,expression of BATF2 mRNA in 13 OTSCC tissues and expression of BATF2 protein in 14 OTSCC tissues were significantly lower than that in adjacent non-tumor mucosa.In 202 paraffin-embedded OTSCC samples,BATF2 was not expressed in 20 cases(9.9％),low expressed in 104 cases(51.5％) and highly expressed in 78(38.6％).BATF2 expression level was significantly correlated with histological differentiation(P=0.002).Patients with low BATF2 expression had significantly poorer overall survival and disease-free survival than those with high BATF2 expression(P＜0.001).Conclusions BATF2 was low expressed in OTSCC and related to tumor differentiation and prognosis and may serve as a prognostic biomarker and potential therapeutic target for this disease.

Objective: To report the medium-long term survival rates of ventricular septal myectomy for treating the patients with hypertrophic obstructive cardiomyopathy and to analyze the predictive factors affecting the outcomes. Methods: A total of 655 consecutive patients who received ventricular septal myectomy in our hospital from 1984-10 to 2014-12 were retrospectively summarized. The cohort study was conducted with questionnaires by cardiovascular nurses. Result: The operative mortality was 1.4% (9/655). The mean follow-up time was (30.8 ± 30.9, from 3 to 213) months, there were 52/646 (7.9%) patients lost contact and 583 patients having NYHA classification at I or II during that period. The overall survival rates for 1 year, 5-year and 8-year were 98.3%, 90.5% and 88.3% respectively. There were 80 patients suffered from end point events including HCM-related death, heart transplantation, repeated myectomy, permanent pacemaker implantation and re-admission for ischemic stroke, tachyarrhythmia, myocardial ischemia or infarction, congestive heart failure. The end point events free survival rates for 1 year, 5-year and 8-year were 94.2%, 76.7% and 65.9% respectively. Multivariable Cox regression analysis presented that age>50 years (HR=2.16, 95% CI 1.36-3.46,P=0.001) and pre-operative atrial ifbrillation (FA) (HR=2.31, 95% CI 1.35-3.94,P=0.002) were the independent predictors for end point events occurrence. Conclusion: Ventricular septal myectomy may achieve good medium-long term survival rate with less adverse event in patients with hypertrophic obstructive cardiomyopathy. Elder than 50 years of age and with pre-operative FA were the independent predictors for adverse events occurrence.

Objective To evaluate the effect of orthopedic clinical practice teaching design based on WeChat platform.Methods From September 2015 to August 2017,62 undergraduate students majoring in clinical medicine in the department of orthopedics of our hospital were selected as the study subjects,and randomly divided into the experimental group and the control group.With 31 interns in each group,the control group implemented the traditional teaching method according to the requirements of the syllabus.The experimental group was attached to WeChat production,push notification and communication of related courses on the basis of the traditional teaching methods.At the end of the teaching,the theoretical and operational tests,the comprehensive quality assessment,the evaluation for teachers' teaching work and the questionnaire survey of the two groups were administrated to evaluate the teaching effect.SAS 9.0 was used to do t-test and CMH-chi-square test.Results The score of the experimental group in the theoretical test [(87.52 ± 5.45) vs.(82.61 ± 7.70)],operational test [(94.36 ± 2.60) vs.(92.26 ± 3.01)],comprehensive quality assessment [(95.94 ± 1.61) vs.(93.42 ± 2.81)] and the evaluation for teachers' teaching work [(94.58 ± 2.06) vs.(92.55 ± 1.69)] were better than those of control group,and there were statistically significant differences.P values were 0.005,0.005,0.000 and 0.000 respectively.The questionnaire survey results show that the experimental group was better than the control group in learning motivation (P=0.035),literature study (P=0.013),curriculum arrangement (P=0.007),teaching satisfaction (P=0.029) and professional recognition (P=0.040).Conclusions The clinical practice teaching method based on WeChat platform is effective and feasible to the orthopedic medical students,which is helpful to improve students' learning initiative and master effective learning strategies.The application is worth promoting.

Objective To investigate the determinants of linezolid-associated neurological adverse reactions in patients with multidrug-resistant tuberculosis and develop a risk prediction model for such adverse events.Methods A prospective cohort study design was employed to select 120 patients with drug-resistant pulmonary tuberculosis who received a chemotherapy regimen containing linezolid at Guangzhou Chest Hospital from April 2023 to January 2024 as the study population.Clinical data,adverse reactions,and plasma concentration of linezolid were collected during fasting and at 2 hours post-medication.Univariate analysis and multivariate logistic regression were conducted to identify factors influencing linezolid-related neurological adverse reactions.Furthermore,a prediction model for such adverse reactions was developed,and its predictive efficacy and calibration ability were evaluated using ROC analysis.Results Re-treatment(OR=2.540,P=0.028),coexistence of cavities(OR=4.092,P=0.021),anemia(OR=10.921,P=0.005),and Cmin≥0.7665 mg/L(OR=6.813,P<0.001)are independent risk factors for the occurrence of linezolid-related neurological adverse reactions.The prediction model,based on these four factors,exhibits an AUC of 0.851(95%CI:0.774～0.929),accompanied by a Youden index of 0.590,a sensi-tivity of 66.7%,and a specificity of 92.3%.Moreover,the prediction model demonstrates excellent calibration ability.(Hosmer-lemeshow χ2=8.719,P=0.273).Conclusion In MDR/RR-TB patients,the presence of cavita-tion,retreatment,and anemia may confer a heightened risk of linezolid-related neurological adverse reactions.A risk prediction model incorporating these four indicators demonstrates significant predictive value for the occurrence of such adverse events.

Objective:To analyze the epidemiological characteristics of the cases firstly reported as "asymptomatic infection of COVID-19" in Guangdong province.Methods:The follow-up observation method was used to continuously track and observe the cases firstly reported as "asymptomatic patients with COVID-19" in Guangdong province from January 14 to March 31, 2020. The epidemiological data of the cases were collected to analyze their epidemiological characteristics, outcome and influencing factors.Results:From January 14 to March 31, 2020, a total of 325 cases were firstly reported as "asymptomatic infections of COVID-19" in Guangdong province. The epidemic curve of asymptomatic infection cases was similar to that of confirmed cases, and it had two peaks. The first peak was from January 27 to February 5, and the second peak was from March 17 to March 26. Of the 325 cases, 184 (56.6%) were subsequently converted to confirmed cases. These cases were defined as incubation period asymptomatic infection cases. The age median of the cases was 40 years, and 93.5% (172/184) of the cases showed symptoms within 3 days after the first positive nucleic acid tests were conducted, and 141 (43.4%) of the 325 cases remained asymptomatic status until they were cured and discharged. They were inapparent infection cases, accounting for 8.6% (141/1 642) of those diagnosed with COVID-19 in Guangdong province during the same period. The age median of inapparent infection cases was 27 years. The median of the interval between the first positive nucleic acid test and discharge was 14 days. Up to 90.8% (138/141) of the inapparent infection cases were discharged for centralized medical observation within 28 days. The longest interval between the first positive nucleic acid test and the last positive nucleic acid test was 73 days. The positive rate of nucleic acid test was 0.3% in close contacts of inapparent infection cases and 2.2% in close contacts of incubation period asymptomatic infection cases. There were significant differences in age distribution and source of infection between incubation period asymptomatic infection cases and inapparent infection cases ( P<0.05). Old age was the risk factor for the conversion of firstly reported asymptomatic infection cases to confirmed cases. Compared with the 0-19-year-old group, The patients aged 40-59 years and 60 years and above were more likely to become confirmed cases. The OR (95 %CI) values were 2.730 (1.380-5.402) and 5.302 (2.199-12.783), and P values were 0.004 and 0.000, respectively. People being infected in China were more likely to become confirmed cases ( OR=7.121, P=0.000). Conclusions:There were asymptomatic infection cases among patients diagnosed with COVID-19. The infectiousness of incubation period asymptomatic infection cases might be stronger than that of inapparent infection cases. The proportion of younger cases among asymptomatic infection cases was higher than that of the confirmed cases. Old age and domestic infection were the risk factors for the conversion of asymptomatic infection cases to confirmed cases, to which more attention should be paid. Further serological investigations are needed to provide a basis for the development of COVID-19 prevention and control strategies.

The robotic bronchoscopy system is a new technology for lung lesion location, biopsy and interventional therapy. Its safety and effectiveness have been clinically proven. Based on many advanced technologies carried by the robotic bronchoscopy system, it is more intelligent, convenient and stable when clinicians perform bronchoscopy operations. It has higher accuracy and diagnostic rates, and less complications than bronchoscopy with the assistance of magnetic navigation and ordinary bronchoscopy. This article gave a review of the progress of robotic bronchoscopy systems, and a prospect of the combination with artificial intelligence.