Objective:To understand the consultation for post-exposure prophylaxis(PEP) services and their related factors among college students who were at high risk for HIV infection in Hangzhou,and to provide a reference basis for formulating an intervention model for college students at high risk of HIV infection.Methods:A cross-sectional survey was conducted between November 2022, and March 2023, in 5 different types of schools in Hangzhou. The subjects should meet the inclusion criteria of age between 18 years and 24 years old self-reported having ever had sex in the past. The sample size was estimated at 864. An online survey was conducted among college students by questionnaire star of an online survey platform to collect their demographic information, sexual behavior characteristics, HIV test status, and consultation for PEP services. The HIV infection risk among participants was evaluated according to their sexual behavior. The consultation for PEP services and the related factors of college students who were at high risk for HIV infection were analyzed.Results:A total of 20 973 college students were surveyed, and 2 291 who have ever had sex were recruited in the study. The proportion assessed as being at high risk for HIV infection was 43.47% (996/2 291), and the proportion of consultation for PEP services was 9.24% (92/996). Multivariate logistic regression analysis showed that among college students who were at high risk for HIV infection, the positive related factors of consultation for PEP services included knowing about PEP services (a OR=17.49, 95% CI: 7.98-38.36) ,having HIV tests (a OR=3.92, 95% CI: 2.08-7.42) and access to condoms on campus (a OR=3.38, 95% CI: 2.02-5.65), and the negative related factor was homosexual orientation (a OR=0.24, 95% CI: 0.06-0.91). Conclusions:Among college students who were at high risk for HIV infection, the proportion of consultation for PEP services was at a lower level. It is necessary to strengthen further the health education of PEP services knowledge among college students, improve the PEP services system, and promote the utilization of PEP services to reduce new HIV infections among college students.

Objective:To understand the consultation for post-exposure prophylaxis(PEP) services and their related factors among college students who were at high risk for HIV infection in Hangzhou,and to provide a reference basis for formulating an intervention model for college students at high risk of HIV infection.Methods:A cross-sectional survey was conducted between November 2022, and March 2023, in 5 different types of schools in Hangzhou. The subjects should meet the inclusion criteria of age between 18 years and 24 years old self-reported having ever had sex in the past. The sample size was estimated at 864. An online survey was conducted among college students by questionnaire star of an online survey platform to collect their demographic information, sexual behavior characteristics, HIV test status, and consultation for PEP services. The HIV infection risk among participants was evaluated according to their sexual behavior. The consultation for PEP services and the related factors of college students who were at high risk for HIV infection were analyzed.Results:A total of 20 973 college students were surveyed, and 2 291 who have ever had sex were recruited in the study. The proportion assessed as being at high risk for HIV infection was 43.47% (996/2 291), and the proportion of consultation for PEP services was 9.24% (92/996). Multivariate logistic regression analysis showed that among college students who were at high risk for HIV infection, the positive related factors of consultation for PEP services included knowing about PEP services (a OR=17.49, 95% CI: 7.98-38.36) ,having HIV tests (a OR=3.92, 95% CI: 2.08-7.42) and access to condoms on campus (a OR=3.38, 95% CI: 2.02-5.65), and the negative related factor was homosexual orientation (a OR=0.24, 95% CI: 0.06-0.91). Conclusions:Among college students who were at high risk for HIV infection, the proportion of consultation for PEP services was at a lower level. It is necessary to strengthen further the health education of PEP services knowledge among college students, improve the PEP services system, and promote the utilization of PEP services to reduce new HIV infections among college students.

Objective:To evaluate the clinical application of online adaptive radiotherapy based on iterative cone-beam computed tomography (iCBCT) for the pelvic malignancies.Methods:This was a prospective clinical trial of iCBCT guided online adaptive radiotherapy for pelvic malignancies in Department of Radiation Oncology, Peking Union Medical College Hospital. Clinical data of 13 patients with pelvic malignancies who received online adaptive radiotherapy from August to November, 2022 were preliminarily analyzed (2 cases of cervical cancer, 4 postoperative cervical cancer, 3 postoperative endometrial cancer, 3 bladder cancer and 1 prostate cancer). The feasibility of online adaptive radiotherapy, adaptive radiotherapy time, the frequency and magnitude of edits for organs at risk and target volume, target volume coverage and organs at risk doses were analyzed. Statistical analysis was performed by SPSS software. Data conforming to normal distribution were described by Mean±SD, and data with non-normal distribution were expressed by M ( Q1, Q3). Data with homogeneous variances were analyzed by t-test, and data with non-normal distribution or heterogeneous variances were analyzed by nonparametric test. Results:The average adaptive time was 15 min and 38 s (from acceptance of acquired CBCT scan to completion of the final plan selection). 85.4% (830/972 fractions) of influencer structures (system-defined organs adjacent to and with high impact on the generation of clinical target volume and planning target volume, primarily bladder, rectum and small intestine in pelvic neoplasms) automatically generated by artificial intelligence required no edits or minor editors, and 89.8% (491/547 fractions) of clinical target volume automatically generated by artificial intelligence required no edits or minor editors. The adapted plan was adopted in 98.5% (319/324 fractions) of radiotherapy fractions. Compared with the scheduled plan, the adapted plan showed better target volume coverage and reduced the dose of organs at risk.Conclusions:iCBCT guided online adaptive radiotherapy for the pelvic malignancies can be achieved within clinically acceptable timeslots. In addtion, better dose coverage of target volume shows the advantages of online adaptive radiotherapy.

Objective:To explore the relationship between thyroid parenchymal echogenicity abnormalities and thyroid function evolution in health examination population.Methods:It was a cohort study. According to the inclusion and exclusion criteria, participants were selected from individuals who underwent thyroid color ultrasound and thyroid function tests at the Health Management Center of Tianjin Medical University General Hospital from January to December 2017. Data including age, gender, smoking history, alcohol consumption history, personal medical history, and thyroid function re-examination information were collected. Follow-up was conducted until the occurrence of thyroid function abnormalities or until the end of the follow-up period. The cumulative incidence rate and incidence density of thyroid function abnormalities were evaluated. Cox regression analysis was used to analyze the relationship between thyroid parenchymal echogenicity abnormalities and thyroid function evolution.Results:A total of 6 754 participants were included in this study, with an average age of (45.80±12.12) years, and females accounted for 42.7%. The mean follow-up time was 1.82 years, with a cumulative follow-up duration of 12 263 person-years. During the follow-up period, 154 new cases of thyroid function abnormalities occurred, with a cumulative incidence rate of 2.28% (95% CI: 1.94%-2.66%) and an incidence density of 12.56/1 000 person-years (95% CI: 10.66/1 000-14.69/1 000 person-years). The multivariate adjusted Cox regression analysis showed that individuals with thyroid parenchymal echogenicity abnormalities had a significantly increased risk of developing isolated thyroid stimulating hormone abnormalities and thyroid function abnormalities, with HR(95% CI) of 3.09 (2.02-4.73) and 2.92(1.96-4.33), respectively, both P<0.001. Stratified analysis showed that, except for body mass index <18.5 kg/m 2, current smoking, and current alcohol consumption, all other stratified factors showed a significant increase in the risk of thyroid function abnormalities in individuals with thyroid parenchymal echogenicity abnormalities. Conclusion:Thyroid parenchymal echogenicity abnormalities are important risk factors for the evolution of thyroid function abnormalities. Continuous monitoring of thyroid function should be given due attention.

Vibrio parahaemolyticus, the main pathogen causing seafood related food poisoning worldwide, has strong biofilm formation ability. ToxR is a membrane binding regulatory protein, which has regulatory effect on biofilm formation of V. parahaemolyticus, but the specific mechanism has not been reported. c-di-GMP is an important second messenger in bacteria and is involved in regulating a variety of bacterial behaviors including biofilm formation. In this study, we investigated the regulation of ToxR on c-di-GMP metabolism in V. parahaemolyticus. Intracellular c-di-GMP in the wild type (WT) and toxR mutant (ΔtoxR) strains were extracted by ultrasonication, and the concentrations of c-di-GMP were then determined by enzyme linked immunosorbent assay (ELISA). Three c-di-GMP metabolism-related genes scrA, scrG and vpa0198 were selected as the target genes. Quantitative real-time PCR (q-PCR) was employed to calculate the transcriptional variation of each target gene between WT and ΔtoxR strains. The regulatory DNA region of each target gene was cloned into the pHR309 plasmid harboring a promoterless lacZ gene. The recombinant plasmid was subsequently transferred into WT and ΔtoxR strains to detect the β-galactosidase activity in the cellular extracts. The recombinant lacZ plasmid containing each of the target gene was also transferred into E. coli 100λpir strain harboring the pBAD33 plasmid or the recombinant pBAD33-toxR to test whether ToxR could regulate the expression of the target gene in a heterologous host. The regulatory DNA region of each target gene was amplified by PCR, and the over-expressed His-ToxR was purified. The electrophoretic mobility shift assay (EMSA) was applied to verify whether His-ToxR directly bound to the target promoter region. ELISA results showed that the intracellular c-di-GMP level significantly enhanced in ΔtoxR strain relative to that in WT strain, suggesting that ToxR inhibited the production of c-di-GMP in V. parahaemolyticus. qPCR results showed that the mRNA levels of scrA, scrG and vpa0198 significantly increased in ΔtoxR strain relative to those in WT strain, suggesting that ToxR repressed the transcription of scrA, scrG and vpa0198. lacZ fusion assay showed that ToxR was able to repress the promoter activities of scrA, scrG and vpa0198 in both V. parahaemolyticus and E. coli 100λpir. EMSA results showed that His-ToxR was able to bind to the regulatory DNA regions of scrA and scrG, but not to the regulatory DNA region of vpa0198. In conclusion, ToxR inhibited the production of c-di-GMP in V. parahaemolyticus via directly regulating the transcription of enzyme genes associated with c-di-GMP metabolism, which would be beneficial for V. parahaemolyticus to precisely control bacterial behaviors including biofilm formation.
Vibrio parahaemolyticus/metabolism* ; Escherichia coli/metabolism* ; Bacterial Proteins/metabolism* ; Transcription Factors/genetics* ; Gene Expression Regulation, Bacterial

Objective To determine the epidemic characteristics of forty-two coronavirus disease 2019 （COVID-19） cluster outbreaks in Hangzhou city and provide scientific evidence for further prevention and control measures. Methods Data of the COVID-19 cluster outbreaks in Hangzhou were obtained from the National Public Health Emergency Management Information System. Epidemic characteristics were summarized by reviewing the epidemiological investigation reports. Results A total of forty-two COVID-19 cluster outbreaks were documented in Hangzhou in 2020， including 130 confirmed cases and 7 cases with asymptomatic infection. The majority occurred from January to February， 2020. Moreover， 92.86% （39/42） of the cluster outbreaks were familial transmission. The proportion of the cluster outbreaks involving 2 cases accounted for 54.7% （23/42）. In the secondary cases， family members accounted for 84.15% （69/82）. Conclusion The COVID-19 cluster outbreaks in Hangzhou mainly occur in families， and the majority of the secondary cases is family members.

With the continuously increasing demands of plastic products in the current society, the challenge of disposing plastic waste is constantly increasing, leading to the urgent need of mitigating plastic pollution. As a consequence, much attention has been paid to biodegradable plastics due to their degradability in a bio-active environment under certain conditions. Biodegradable plastics herald vast development potentials and considerable market prospects. The degradation of numerous types of biodegradable plastics will be affected by many factors. A thorough understanding of degradation mechanisms as well as functional microbial strains and enzymes is the key to comprehensive utilization and efficient treatment and disposal of biodegradable plastics. The article summarized the types, properties, advantages and disadvantages, and main applications of common biodegradable plastics. The degradation mechanisms, functional microbial strains and enzymes, as well as the degradation degree and duration under different environmental conditions, were also summarized. This review may help better understand the degradation of biodegradable plastics wastes.
Biodegradable Plastics ; Biodegradation, Environmental

Objective: To investigate the epidemiological characteristics of malaria in Hangzhou City from 2004 to 2021, so as to provide the evidence for formulating the post-elimination control strategy for malaria in Hangzhou City. Methods: The epidemic situation of malaria in Hangzhou City from 2004 to 2021 were collected from the National Information System for Disease Control and Prevention in China, and the temporal, spatial and human distributions of malaria cases and the source of malaria infections were analyzed in Hangzhou City during the pre-elimination stage (2004 to 2009), the elimination stage (2010 to 2015) and the post-elimination stage (2016 to 2021). Results: Totally 602 malaria cases were reported in Hangzhou City from 2004 to 2021,and the annual mean incidence of malaria was 0.22/105, 0.20/105 and 0.18/105 during the pre-elimination, elimination and post-elimination stages, appearing a tendency towards a decline. Men accounted for 63.96%, 85.07% and 93.75% of all malaria cases and there were 67.86%, 82.84% and 80.00% of cases at ages of 18 to 50 years during the pre-elimination, elimination and post-elimination stages, both appearing a tendency towards a decline (χ2trend=56.748, P<0.001; χ2trend=39.971, P<0.001). The predominant occupation of malaria cases shifted from farmers or migrant workers to multiple occupations, and the proportion of commercial servants increased from 4.87% during the pre-elimination stage to 24.38% during the post-elimination stage (χ2trend=73.308, P<0.001). The proportion of Plasmodium vivax malaria cases reduced from 96.43% during the pre-elimination stage to 7.50% during the post-elimination stage, and the proportion of P. falciparum malaria cases increased from 3.57% to 71.25%, while P. ovale, P. malariae and mixed infections were identified since 2010. There was a significant season-specific incidence of P. vivax malaria during the pre-elimination stage, and the period between May and October was an epidemic season; however, there was no season-specific incidence of P. vivax malaria during the elimination and post-elimination stages. The regional distribution of malaria cases presented a tendency towards a shift from suburb and rural areas to urban areas (χ2trend=74.229, P<0.001). No local cases were detected in Hangzhou City since 2010, and 94.22% of malaria cases were overseas imported cases after malaria elimination, including 90.61% from Africa. Conclusions oung and middle-aged men were high-risk populations for malaria in Hangzhou City from 2004 to 2021, and overseas commercial servants gradually became the predominant source of malaria infections, with malaria parasite species tending to be diverse. Improving the management of overseas imported cases and timely identification and treatment of cases are major interventions to consolidate malaria elimination achievements in Hangzhou City.

Objective:To study the clinical efficacy of chimeric antigen receptor T-cell (CART) treatment followed by a second allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with B-cell acute lymphoblastic leukemia (ALL) who relapsed following the first HSCT.Methods:Retrospective analysis of the clinical characteristics and prognosis of 41 patients with B-cell ALL who received a second allo-HSCT from October 2015 to June 2020 in Hebei Yanda Lu Daopei Hospital. After the first HSCT, all patients received CD19-CART, or CD22-CART treatment following a relapse of bone marrow morphology or extramedullary leukemia.Results:A total of 41 patients (male, 21; female, 20) were included in this study. The median age at the second HSCT was 16 (3-46) years. There were 31 cases of bone marrow recurrence (75.6%) , 5 cases of extramedullary recurrence (12.2%) , and 5 cases of bone marrow and extramedullary recurrences (12.2%) . After relapse, 35 patients (85.4%) received CD19-CART treatment, 2 patients received CD22-CART treatment (4.9%) , and 4 patients received CD19-CART and CD22-CART treatments (9.8%) . The expected 3-year overall survival (OS) , leukemia-free survival, cumulative relapse incidence, and non-relapse mortality (NRM) of patients after the second HSCT were 48.9% (95% CI 23.0%-70.6%) , 41.8% (95% CI 17.3%-64.9%) , 8.8% (95% CI 2.9%-26.4%) , and 51.1% (95% CI 31.2%-83.6%) , respectively. The 1-year OS of patients who relapsed ≤6 months and >6 months after the first HSCT were 45.0% (95% CI 12.7%-73.5%) and 75.0% (95% CI 51.4% -88.8%) ( P=0.017) , respectively. Conclusion:CART bridging in the second HSCT enables some B-cell ALL patients who relapsed after the first HSCT to achieve long-term survival. However, because of the high NRM, further modifications could help improve the outcome.

Objective:To study the transcriptional regulation of pilABCD by the master quorum sensing (QS) regulator OpaR in Vibrio parahaemolyticus. Methods:Total RNAs were extracted from the wild type (WT) and opaR mutant (Δ opaR) strain. Quantitative real-time PCR (qPCR) was employed to calculate the transcriptional variation of pilA (the first gene of pilABCD operon) between WT and Δ opaR. The regulatory DNA region of pilABCD was cloned into the corresponding restriction endonuclease sites of pHRP309 harboring a promoterless lacZ reporter gene. The recombinant pHRP309 plasmid was then transferred into WT and Δ opaR, respectively, to detect the β-galactosidase activity in cellular extracts using a β-Galactosidase Enzyme Assay System (Promega). The primer extension assay was applied to map the transcription start site of pilABCD using the total RNAs extracted from the WT strain as the template. The regulatory DNA region of pilABCD was amplified by PCR, and the over-expressed His-OpaR was purified under native conditions with nickel loaded HiTrap Chelating Sepharose columns (Amersham). Thereafter, the electrophoretic mobility shift assay (EMSA) was applied to analyze the DNA-binding activity of His-OpaR to the target DNA in vitro, and the DNase I footprinting assay was further employed to detect the DNA-binding sites of His-OpaR within the target DNA. Results:The results of qPCR and LacZ fusion assays showed that OpaR activated the transcription of pilABCD, leading to a gradual increase in the expression level of pilA with the extension of culture time. The primer extension assay detected only one transcription start site located at 155 bp upstream of pilA. The results of EMSA and DNase Ⅰ footprinting assays showed that His-OpaR protected two DNA regions located from -246 to -197 bp and -181 to -131 bp upstream of pilA. Conclusions:Vibrio parahaemolyticus OpaR activated the transcription of pilABCD in a direct manner.