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.

Objective: To analyze the use of preexposure prophylaxis (PrEP) among male students who had sex with men (MSM) with different sexual behavior patterns using potential categories, so as to provide evidence for determining the use patterns of PrEP consistent with MSM. Methods: A questionnaire survey was conducted by proportional sampling method on MSM in 31 provincial administrative regions in mainland China from 20 October to 30 December 2021, a total of 1 040 students were selected for the study. Latent variable analyses were conducted on a total of seven sexual behavioral characteristics, including knowledge of sexual partner HIV infection, frequency of condom use, number of sexual partners, engaging in group sex, provision of commercial sex, use of sex aids, and history of sexually transmitted infections (STIs) in the past year. And demographic characteristics were analyzed by Logistic regression analysis. The rates of PrEP awareness, willingness to use and usage rate in different sexual behavior risk groups were investigated. Results: Student MSM could be divided into two potential category groups:a lowrisk behavior group (82.4%) and a highrisk behavior group (17.6%). The PrEP usage rate (15.8%) was higher in the highrisk behavior group, and the difference was statistically significant compared to the lowrisk behavior group (7.2%) (χ2=13.43, P<0.05). Student MSM residing in the northeast, south, and northwest of China, in the pilot city, and with a sex role of "0.5" (possible acceptance and insertion of sexual behavior) were more likely to be in the highrisk behavior group (OR=3.13, 3.07, 3.87, 2.22, 1.66, P<0.05). Conclusion Student MSM in highrisk and lowrisk sexual differs in the behavior of PrEP, and targeted interventions should be implemented to promote the use of PrEP and reduce HIV infection in this population.

Objective: To explore the pre-exposure prophylaxis (PrEP) awareness, willingness, uptake patterns, barriers and needs among Chinese student men who have sex with men (MSM), so as to provide relevant evidence for targeted interventions with PrEP. Methods: A proportional sampling method was used to conduct a cross sectional survey of MSM aged 16 years and older residing in 21 provinces, municipalities, and autonomous regions in mainland China between October 20 and December 20, 2021, to collect information on demographic and sexual behavioral characteristics, and 923 students of them were selected as the subjects of this study. The chi-square test and Fisher s test were used for univariate analysis, followed by multivariate Logistic regression to analyze the influencing factors of PrEP awareness and uptake. Results: According to the cascade analysis method, the awareness, willingness, uptake and adherence rates of PrEP among the student MSM were obtained as 88.95%, 67.36%, 13.20% and 45.21 %, respectively. HIV testing more than once in the last 3 months, and all of them were aware of the HIV test results of their sexual partners, and those with high frequency of condom use had a higher rate of awareness ( OR =2.32, 1.79, 1.69, P <0.05). Willingness rates were higher for those from the pilot city, using substances, and HIV testing more than once in the last 3 months ( OR =2.13, 1.65, 1.69, P <0.05). Higher rates of uptake were found among those from high risk and pilot areas, presence of commercial sex, substance use, and high literacy ( OR =5.60, 3.54,2.81, 1.92, 4.54, P <0.05). Adherence rates were higher among those who used one pill per day or both ( OR =12.77, 13.26, P <0.05). The barriers and needs faced by student MSM were primarily personal concerns about medication side effects, preventative effects, and confidence in sexual behavioral styles, and the high cost of medication and related service costs. Conclusions The student MSM population in China is characterized by high awareness, low willingness, low uptake, and low adherence to PrEP. Targeted interventions should be considered and tailored by the departments to facilitate PrEP promotion among student MSM.

The cardiac conduction system (CCS) is a set of specialized myocardial pathways that spontaneously generate and conduct impulses transmitting throughout the heart, and causing the coordinated contractions of all parts of the heart. A comprehensive understanding of the anatomical characteristics of the CCS in the heart is the basis of studying cardiac electrophysiology and treating conduction-related diseases. It is also the key of avoiding damage to the CCS during open heart surgery. How to identify and locate the CCS has always been a hot topic in researches. Here, we review the histological imaging methods of the CCS and the specific molecular markers, as well as the exploration for localization and visualization of the CCS. We especially put emphasis on the clinical application prospects and the future development directions of non-destructive imaging technology and real-time localization methods of the CCS that have emerged in recent years.

Objective: To investigate the current situation and related factors of antiretroviral therapy (ART) among HIV infected male students engaging in men who have sex with men (MSM), so as to provide the reference data for HIV prevention and treatment. Methods: In November 2021, 137 MSM students from 31 provincial administrative regions in China were recruited. An online survey was conducted to collect data on demographic characteristics, ART status, CD4 count, and HIV viral load before treatment. Logistic regression was used to analyze the factors related the effectiveness of ART in MSM. Results: Among the included research subjects, 14.6% had late detection of HIV,97.1% of participants were currently undergoing ART. Among those whose ART duration was less than 6 months, while 76.9% were undergoing ART. Logistic regression indicated that HIV infected students who received ART for more than 24 months ( OR =5.28, 95% CI =1.38-20.22) had a higher rate of successful HIV suppression. HIV infected students who reported physical sensory side effects ( OR =0.08, 95% CI =0.01-0.71) and cognitive side effects ( OR =0.28, 95% CI =0.09-0.90) were more likely to experience failure of ARI inhibition ( P <0.05). Conclusions There is still room for improvement in the efficacy of ART among MSM students. Strategies to improve treatment adherence must consider individual variances among HIV infected patients and the side effects of medications when designing treatment plans.

Polyetheretherketone (PEEK) as a new type of thermoplastic engineering plastic, has good biological activity, elastic modulus close to human cortical bone and radiation permeability, and has been widely used in medical field. This study aims to explore the safety and clinical efficacy of using 3D printing personalized PEEK materials to repaire scapular bone defects after bone tumor resection. A total of 6 patients who underwent the implantation of 3D printed PEEK scapular prosthesis from January 2020 to December 2021 in Yunnan Cancer Hospital were retrospectively analyzed. There were 3 males and 3 females, with age ranged from 14 to 52 years. There were 1 case of synovial sarcoma, 1 of Ewing's sarcoma, and 4 of chondrosarcoma. PEEK prosthesis was designed and fabricated based on CT data before surgery. Tumor resection and prosthesis replacement were performed under the premise of ensuring safe surgical boundaries, including 2 cases of total scapular prosthesis replacement and 4 cases of partial scapular prosthesis replacement. The operation time was 90-170 min, and the intraoperative blood loss was 100-400 ml. All 6 patients received satisfactory follow-up, with a tumor progression free survival time of 16-28 months. No tumor recurrence or metastasis was observed, and all patients survived tumor free. At last follow-up, the Constant-Murley shoulder joint score was a minimum of 62 points and a maximum of 68 points. The Japanese Orthopaedic Association's shoulder joint score was 63 points minimum and 78 points maximum. Computer-aided design 3D printing PEEK material prosthesis has certain advantages in the treatment of scapular tumor limb salvage. It has light weight, well adapted, relatively simple installation, good histocompatibility, and can obtain a better appearance and function of the shoulder joint after operation. It can become one of the options for limb salvage treatment of scapular tumor.

Abstract OBJECTIVE To establish an efficient and simple HPLC-MS/MS method for determination of flucloxacillin in newborn plasma, and to investigate the interaction between ambroxol and flucloxacillin in newborns. METHODS The samples were analyzed by API4000 HPLC-MS/MS. Ultimate XB-C18 column(2.1 mm×100 mm, 5 μm) were carried out. The mobile phase was composed of water-0.1% formic acid(A) and acetonitrile-0.1% formic acid(B). The quantitative analysis of the ion transitions were monitored at m/z 452.6→284.2 for flucloxacillin and m/z 821.4→397.3 for rifampicin(internal standard). RESULTS The linear range of flucloxacillin under this analysis method was 0.20-80 ng·mL-1, and the lower limit of quantification was 0.20 ng·mL-1; The intra-day and inter-day precision of flucloxacillin were both less than 8.23%; The extraction recovery was in the range of 85.3%-89.2%, and the matrix effect was between 89.3%-92.3%; The stability of plasma samples was good under conditions of 12 h at room temperature, 4 h at room temperature after treatment, repeated freeze-thaw for 3 times, and -20 ℃ freezing for 30 d. The results of clinical samples indicated that the combination of ambroxol could significantly increase the blood concentration of flucloxacillin. CONCLUSION The established HPLC-MS/MS method is accurate, sensitive and can be used for the determination of flucloxacillin concentration in neonatal plasma. The results of clinical samples indicate that ambroxol can significantly increase the blood concentration of flucloxacillin. There are drug interactions between ambroxol and flucloxacillin.

Objective: To understand the basic characteristics, sexual behavior and the use of recreational new drugs of young men who have sex with men (MSM) in Tianjin, and to explore the characteristics of young MSM who use recreational drugs, so as to provide reference for the policy making of HIV/AIDS prevention and control in universities. Methods: From January 1, 2018, solstice to December 31, 2018, participants were recruited in the bathrooms, bars and social network sites in Tianjin by snowball sampling. The basic demographic information, sexual behavior and recreational drug use of the participants were collected through face to face interviews and questionnaires. Logistic regression was used to analyzed the characteristic differences drug users and non users among young MSM. Results: A total of 826 young MSM were included in the study, 32 were infected with HIV, and the overall prevalence rate was 3.87 %. Totally 371 (44.92%) were drug users. Rush Poppers were the most common used drug ( 98.65 %). Of the young MSM using new drugs, 306 (82.48%) multiple drugs were used, 65 people ( 17.52 %) only one drug has been used. Among new drug users, multiple drug users had higher HIV prevalence rate (16.92%) than single drug users (4.57%). There were statistically significant differences between drug users and non users in age, age of first sexual behavior, household registration, sexual orientation, education level, sexual partners seeking routes, unprotected anal intercourse and HIV testing history( OR=3.70，5.51，0.51，0.60，4.64，0.40，0.52，1.98，2.29，P <0.05). Conclusion The utilization rate of recreational drugs among young MSM in Tianjin was high. Relevant departments should strengthen the propaganda of recreational drugs and HIV prevention among college students, improve the sexual health awareness of young MSM, and establish a long term HIV and recreational drug prevention system.

Salmonella enterica serovar Enteritidis (SE) is one of the most important zoonotic pathogens that cause enteritis and systemic infection in animals and human. Understanding invasive capacities of SE isolates is of vital importance to elucidate pathogenesis of Salmonella infection. To improve the throughput capacity and repeatability of classical gentamicin protection assay (GPA), a modified PGA was developed by taking high-throughput advantage of 96-well cell plates and multichannel pipettes. In addition, drop plate technique rather than spread plate method was applied in the modified GPA protocol for bacterial enumeration. The modified GPA protocol was evaluated by phenotyping intracellular replication of a high virulent and a low virulent SE isolates, JL228 and LN248, in a phagocytic cell line RAW264.7. The protocol was then applied in invasive phenotype determination of 16 SE strains to non-phagocytes (HT-29) and the intracellular replication of 43 SE strains to phagocytes (RAW264.7). Significant lower intra-group and inter-group coefficient of variations of the modified GPA was observed, implying good repeatability and reproducibility over traditional protocol. Further, replication phenotypes were also correlated with those from direct observation by confocal microscopy. Collectively, the improved GPA protocol had advantages of high throughput capacity, good repeatability and reliability, it was also noticed that the protocol also represented a fast and labor-saving alternative scheme for the invasive phenotype determination of Salmonella Enteritidis, and providing reliable phenotype profiles for Salmonella-host interplay interpretation.
Animals ; Gentamicins/pharmacology* ; Humans ; Phenotype ; Reproducibility of Results ; Salmonella Infections, Animal ; Salmonella enteritidis

Objective To describe the clinical characteristics of hypervirulent Klebsiella pneumoniae (hvKP) infection.To analyze the antibiotic susceptibility of hvKP to provide the empiric antibiotic options.To investigate capsule serotype and sequence type (ST) of hvKP and their correlation with clinical profiles.Methods hvKP was defined as bacteria isolated from patients with community-acquired pyogenic liver abscess (CA-PLA) with co-infection sites outside liver or a bloodstream infection in a host without underlying biliary tract diseases.Patients with CA-PLA hospitalized in the First Hospital of China Medical University were retrospectively analyzed from January 2011 to December 2017.Antibiotic susceptibility was detected by automatic bacterial identification and antibiotic susceptibility analysis system in vitro.Polymerase chain reaction method and gene sequencing were used to detect the main capsule serotype and ST.Results A total of 140 cases with hvKP infection were enrolled.The co-infections outside liver abscess included 98 bloodstream infections,53 pneumonia,11 perianal abscess,10 urinary system infections,3 subphrenic abscess,3 endophthalmitis,2 spleen abscess,and other miscellaneous infections including 1 peritonitis,1 skin and soft tissue infection,1 myelitis,1 colitis,1 psoas major abscess and 1 myocardial abscess.Among the 140 cases,106 presented with single co-infection site,32 with 2 sites,and 2 with 3 sites.HvKP manifested high antibiotic susceptibility up to 80％ for most commonly used antibiotics.Capsule serotyping of 4,3 revived isolates indicated that K1 serotype accounted for 53.49％ (23/43),K2 34.88 (15/43),K54 2.33％ (1/43),K57 2.33％ (1/43),and other serotypes 6.98％(3/43).There was no significant distribution among K1,K2,K54,and K57 of hvKP capsule serotypes in patients with or without diabetes mellitus (P＞0.05).Multilocus sequence typing (MLST) suggested that ST23 and ST65 were predominant accounting for 39.53％ (17/4.3) and 25.58％ (11/4.3) respectively.No serotype or ST predominance was seen in any of the clinical infections.Conclusion HvKP is related to a wide spectrum of infectious diseases,including multiple extrahepatic sites and bloodstream infections besides CA-PLA with high antibiotic susceptibility.K1 and K2 are the predominant capsule serotypes,and ST 23 and ST65 are the predominant sequence types.