Objective: To explore the potential category patterns of risk prevention and control behaviors of HIV infection among young students who have sex with men (MSM) and their impact on HIV infection and late detection, aiming to optimize intervention strategies. Methods: From September 2017 to December 2024, a total of 1 637 MSM young students in Tianjin were recruited through both online and offline channels. Latent class analysis was applied to classify 11 HIV risk prevention and control behaviors [condom use during the most recent anal sex in the past 6 months, consistent condom use, use of water based lubricants, abstinence from recreational drugs, regular on site professional testing, fixed sexual partners, partner testing, awareness of partner s HIV testing results, testing before sexual activity, nucleic acid testing, and use of pre exposure prophylaxis (PrEP) or post exposure prophylaxis (PEP)]. Multivariate Logistic regression analyzed associations between demographic characteristics/intervention services factors and latent classes. Differences in HIV infection and late detection across behavior patterns were compared. Results: HIV risk prevention and control behaviors among MSM students were classified into three latent classes:condom dependent group (38.42%), low prevention group (27.73%), and comprehensive prevention group (33.85%). Students who received condom promotion/testing services were more likely to belong to the comprehensive prevention group ( OR =5.58), while those who received peer education were less likely to the comprehensive prevention group ( OR =0.43) (both P <0.01). Among the MSM student population, the HIV infection rate was 4.83%, with 2.26% of cases detected late. The HIV infection rate (1.45%) and late detection proportion (0.82%) in the comprehensive prevention group were lower than those in the low prevention group (7.89% and 3.83%, respectively) ( χ 2=16.20, 7.31, both P <0.01). Conclusions HIV risk prevention and control behaviors among MSM young students exhibit significant heterogeneity. Comprehensive prevention strategies can effectively reduce HIV infection and late detection risks. It is necessary to optimize peer education content and improve the accessibility of diversified prevention measures such as PrEP/PEP to enhance HIV prevention and control.

Tongue coating(TC)is a layer of coating on the surface of the tongue dorsal mucosa,and observing its variable color and property is an important content of tongue diagnosis in traditional Chinese medicine(TCM).A large amount of existing evidence has showed that TC images and its material composition have important diagnostic value for systemic diseases,which constructs the modern scientific foundation for the scientific connotation of observing TC to assist clinical syndrome differentiation,prescription,and medication.However,it is still wanting in-depth exploration on the cellular and molecular biological mechanisms underlying TC forma-tion.The current review systematically summarizes the main research literatures,proposes the potential regulatory mechanism of the im-muno-neuro-endocrine system,biological toxins,and physical factors in the development of tongue coating,and draws upon innovative approach to exploring the biological mechanism of TC microenvironment including microorganisms,immunity,endocrine,mechanical stretching,temperature,etc.These advances provide valuable research ideas and technical platform for in-depth exploration on the bi-ological mechanisms of TC variety,and promote the scientific research and clinical application of tongue diagnosis.

Objective:To determine incidence of seasonal influenza virus infection in the community and to analyze the factors influencing seasonal influenza virus infection.Methods:This study recruited residents aged 6-59 years to build a cohort in 15 villages/streets in Macheng city in November 2019. Meanwhile, a cross-sectional baseline survey was conducted immediately to collect sera, information on demographics and child protection knowledge, behaviors, as well as attitudes using a questionnaire from the participants enrolled in the cohort (i.e., before the influenza epidemic season). In July 2020, a cross-sectional follow-up survey was conducted to collect sera once again (i.e., after the influenza season). Paired sera from the two cross-sectional surveys were tested for influenza virus-specific antibodies by hemagglutination inhibition (HI) test or micro-neutralization (MN) test using a circulating representative strain of each subtype/lineage of influenza virus as the test antigen. The infections with influenza virus subtype/lineage was confirmed if there was a four-fold or more increase in titers of antibodies against circulating representative strain of the subtype/lineage of influenza virus. Factors influencing infection with influenza A (H3N2) and B/Victoria viruses were analyzed using univariable and multivariable logistic regression.Results:In November 2019, 800 study participants were enrolled in the cohort, including 340 children aged 6-17 years and 460 adults aged 18-59 years; 605 study participants (including 224 children and 381 adults) were followed up in July 2020 and their paired sera were obtained before and after the influenza season. 25.3% (153/605) of the participants were confirmed to be infected with at least one subtype/lineage of seasonal influenza virus by HI and MN tests. The overall incidence of influenza viruses of all subtypes/lineages in children was 44.2% (95% CI: 37.6%-50.8%) which was significantly higher than the incidence of 14.1% in adults (95% CI: 10.7%-17.7%). Children had the highest incidence of influenza A (H3N2) virus infection, followed by B/Victoria. MN or HI antibody titers in A (H3N2)[ OR=0.88 (95% CI: 0.84-0.93)] and B/Victoria[ OR=0.97 (95% CI: 0.95-0.99)] before the influenza season were significantly associated with whether children were infected with that subtype/lineage of influenza virus. Conclusions:The residents aged 6-59 years in Macheng city had a substantial incidence of seasonal influenza virus infection during the influenza season from winter 2019 to spring 2020. Notably, almost half of children aged 6-17 years have been infected with seasonal influenza virus. Higher titers of HI/MN antibodies against seasonal influenza virus before the influenza season would be likely to reduce the risk of infection with influenza A (H3N2) and B/Victoria.

Adjusting time-dependent covariates into prediction models may help improve model performance and expand clinical applications. The methodology of handling time-dependent covariates is limited in traditional regression strategies (i.e., landmark model, joint model). For example, the number of predictors and practical situations which can be handled are restricted when using regression models. One new strategy is to use machine learning (i.e., neural networks). This review summarizes the methodology of handling time-dependent covariates in prediction models, such as applicable scenarios, strengths, and limitations, to offer methodological enlightenment for processing time-dependent covariates.

Objective: To explore the clinical efficacy of plate fixation via the lateral transverse incisions and double-window approaches for the treatment of intra-articular calcaneal fractures. Methods: A retrospective analysis was performed on the data of 21 intra-articular calcaneal fractures (22 feet) which had been treated at Department of Orthopaedics, The Second Affiliated Hospital to Anhui Medical University from May 2014 to April 2016. There were 19 males and 2 females, aged from 20 to 60 years (average, 38.3 years). The fracture affected 13 left feet and 9 right feet. According to the Sanders classification, 10 feet were type Ⅱ, 11 type Ⅲ and one type Ⅳ. They were treated by plate fixation via the lateral transverse incisions and double-window approaches. Early complications within 3 months after operation, the length, width, height, Böhler angle and Gissane angle of the calcaneus one year after operation, functional recovery of the affected feet at the last follow-up, and complications were recorded. Results: The 21 patients were followed up for 21 to 44 months (mean, 36.7 months). Incisions were all healed at the first postoperative stage with no serious skin or soft tissue complications like superficial infection, deep infection or wound dehiscence. At the early stage, one patient suffered epidermal necrosis at the margin of incision, which was cured after dressing change. None of the patients developed subtalar arthritis by the last follow-up. The preoperative length, width, height, Böhler angle and Gissane angle of the calcaneus (respectively, 68.6±1.2 mm, 46.7±0.8 mm, 39.1±2.0 mm, 5.4°±12.1° and 104.3°±10.2°) were significantly improved to 71.7±1.6 mm, 48.8±2.0 mm, 32.8±1.3 mm, 29.2°±6.8°, and 120.8°±6.2° one year after operation(P<0.05). At the last follow-up, their AOFAS ankle-hind foot scores averaged 92.7 points (from 73 to 98 points); 17 feet were rated as excellent, 3 as good and 2 as moderate, giving an excellent and good rate of 90.1%. Conclusion Plate fixation via the lateral transverse incisions and double-window approaches can reduce incidences of postoperative soft tissue complications and subtalar arthritis, leading to good clinical results in the treatment of intra-articular calcaneal fractures.

In this study, a new medical microbiology experiment teaching system, which was based on outcome-based education combined with inquiry-based teaching model, was developed and evaluated. According to the professional requirements of doctors, the objectives of emotion and comprehensive experimental ability were added, and the requirement for experimental operation skills was raised. In accordance with the concept of inquiry-based teaching, experimental contents were reorganized, and practical operation contents and comprehensive analytical experiments were increased to facilitate students' abilities of independent thinking and innovation. In addition, the proportion of microbiology laboratory examination was increased, experimental skill examination was focused, the assessment method was reformed, and extracurricular interest groups were established to deepen the learning. The teaching effect was evaluated by questionnaire, performance and follow-up survey. The result showed that the new model increased the students' course scores, improved their capability in innovation, academic writing and clinical working, and strengthened the weakness of traditional teaching in application and exploration, providing a new idea for the reform in medical microbiology experiment teaching.

Acute closed Achilles tendon rupture is a common sport injury.Rupture of the Achilles tendon may limit the ability of physical exercises and activities of daily life.Conservative treatment has long recovery time and high risk of re-rupture of Achilles tendon.In recent years,with the early functional rehabilitation exercise,including early weight bearing and ankle joint flexion and extension exercise under the protection of orthopaedic braces,re-rupture risk of Achilles tendon has been significantly reduced,thus conservative treatment is becoming more and more popular.The surgical treatment mainly includes traditional open surgery and minimally invasive surgery.Minimally invasive treatment has less trauma,low re-rupture rate like open surgery,low risk of wound infection and is helpful for early rehabilitation.However,the risk of the sural nerve injury is higher.Open surgery has clear operating field and low re-rupture rate and low risk of the sural nerve injury.However,it still has some problems such as superficial and deep infection of the incision,suture reaction,tissue adhesion and so on.Both of them can achieve satisfactory results in the treatment of acute closed Achilles tendon rupture.Although the mechanism of injury of acute closed rupture of the Achilles tendon and epidemic characteristics have a deeper understanding,including degenerative tendon rupture and mechanical rupture of Achilles tendon,the incidence rate showed a rising trend,and affected by the geographical,gender,age and other factors,due to the existence of a variety of patient groups,there is still controversy over the optimal treatment modalities resulting from the diversity of the patient population.According to the individual differences of different groups of patients,the combination of early rehabilitation exercise can achieve satisfactory clinical effects as long as the treatment methods are appropriate.At present,the effect of biological therapy on the healing of Achilles tendon and the prevention of deep vein thrombosis are still controversial.There is no definitive evidence for the effectiveness of biological therapy and the need for prophylactic anticoagulation.The purpose of this study is to summarize the treatment of acute closed Achilles tendon rupture,and to discuss the importance of early functional exercise for acute closed Achilles tendon rupture and its effect on prognosis.

Objective To investigate the expressing patterns of serum inflammatory factors in patients with gastric cancer(GC)with different types of tongue fur.Methods GC patients with different types of longue fur(n=134)and non-GC subjects with different types of tongue fur(n=93)were chosen from clinic.The levels of serum inflammatory factors were detected by using electro-chemiluminescence immu-noassay(ECLIA),and correlation between types of tongue fur and serum inflammatory factors was ana-lyzed by using multi-factor association method.Results The levels of serum interleukin-17α(IL-17α) had significant difference in GC patients with different types of longue fur(P<0.05).The analysis on fur color showed that level of serum IL-17αwas 3.062 ng/L in GC patients with yellow fur and 3.982 ng/L in those with white fur(P<0.05).ROC analysis showed that the sensitivity was 72.7%,specific-ity was 91.3%and AUC(95% CI)was 0.639(0.539 -0.739)of serum IL-17αin distinguishing white fur and yellow fur,and cutoff value was 6.033 ng/L.The similar tendency was identified in non-GC subjects.The correlation analysis showed that there were 20 serum inflammatory factors with signifi-cant positive correlation in GC patients with the same types of tongue fur,and significant negative correla-tion in GC patients with different types of tongue fur.Conclusion The level of IL-17αcan significantly distinguish white tongue fur and yellow tongue fur.The white-yellow tongue fur and thin-thick tongue fur may reflect adverse inflammatory status in GC patients.

Objective: To investigate the effectiveness of modified suture technique in the treatment of acute closed Achilles tendon rupture.

BACKGROUND:Positioning of the distal locking screws of a tibial intramedulary nail is often chalenging and time consuming. The traditional free-hand technique under fluoroscopic control involves considerable radiation exposure.OBJECTIVE: To evaluate the results of a new electromagnetic navigation system (TRIGEN-SURESHOT navigation system) for distal locking of tibial intramedullary nail in tibial diaphyseal fracture and to compare the effects with the free-hand method.METHODS: Forty-five cases of tibial diaphyseal fracture in the Second Hospital of Anhui Medical University from May 2014 to August 2015 were analyzed retrospectively, and were divided into two groups. Patients in navigation group (n=23) were treated with intramedullary nail using the TRIGEN-SURESHOT navigation system for distal locking, and the remainings in free-hand group (n=22) were given the free-hand method.RESULTS AND CONCLUSION: All cases were followed up for 17-32 months. The one-time success rate of distal locking nail operation was 100％ in the navigation group, which was significantly higher than that in the free-hand group (P < 0.05). The locking nail time in the navigation group was significantly less than that in the free-hand group (P < 0.05).No significant differences were found in the incidence of adverse events and fracture healing time between two groups (P > 0.05). To conclude, the effect of the TRIGEN-SURESHOT navigation system for distal locking of tibial intramedullary nail is satisfactory, exhibiting the advantages of short operation time, high success rate, and no radiation.