Hepatitis B virus （HBV） exclusively infects liver parenchymal cells and forms covalently closed circular DNA （cccDNA） within their nuclei. HBV cccDNA serves as the essential template for viral gene transcription， the sole source of progeny virus production， and the key driver of viral antigen expression， and it is the molecular basis for the persistence of HBV infection. Therefore， elimination and/or functional silencing of cccDNA is the key to eradicate chronic HBV infection. This article discusses the critical scientific issues that need to be solved during elimination of the harm of HBV infection from the perspectives of the synthesis， transcription， and clearance of cccDNA， as well as the impact of nonparenchymal cells on cccDNA， in order to provide a reference for eradicating HBV infection in the future.

OBJECTIVE To provide references for optimizing the review and approval system of clinically urgent overseas-marketed drugs in China. METHODS The characteristics of the review and approval system for clinically urgent overseas-marketed drugs were analyzed. A comparative research method was employed to examine differences between China and Australia， Switzerland， and Canada in three dimensions： qualification determination for clinical urgency （i.e.， access qualification）， review methods， and approval modalities. RESULTS & CONCLUSIONS In China’s current system， the legal nature of communication and consultation meetings is ambiguous， as the qualification determination function is embedded within technical consultation procedures without remedy channels. The pre-marketing clinical trial exemption for drugs is disconnected from the post-marketing confirmation obligation， and insufficient access to complete overseas review information weakens risk control effectiveness. A differentiated triage mechanism based on the timing of global approval has not been established， providing insufficient incentives for global simultaneous research and development. International typical regulatory models set access qualification， review methods， and approval modalities as independent modules， forming a quid pro quo relationship by relaxing pre-marketing access conditions and establishing post-marketing conditional approval mechanisms. It is recommended to formulate technical guidelines for the determination of clinically urgent drugs to clarify objective discretionary benchmarks， clarify the legal nature of communication and consultation meetings and allocate remedy channels， mandatorily include clinical trial-exempted varieties in the conditional approval procedure and establish a negative signal linkage mechanism， and implement differentiated triage based on approval timing， so as to improve China’s review and approval system.

Objective To explore the biological mechanism of radiation resistance in esophageal squamous cell carcinoma(ESCC)and search for effective sensitization targets.Methods We retrieved 186 signaling pathways and related gene information from the MSigDB database.We also obtained RNA transcriptome data of ESCC patients using the Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.We collected clinical pathological characteristics and tissue samples of 97 ESCC patients in our hospital from 2013 to 2020.Gene set variation analysis(GSVA)was made to calculate KEGG signaling pathway score,radiotherapy resistance related signaling pathways were screened through random forest algorithm,key genes in the pathway were screened using DESeq2,and a radiotherapy efficacy prediction model was constructed based on support vector machine-recursive feature elimination(SVM-RFE).The results were validated through experiments such as Western blotting and clonogenic assay.Results Based on the KEGG signaling pathway and GSVA enrichment score,random forest analysis showed that in the TCGA and GSE45670 cohorts,the contribution of tryptophan metabolism pathway enrichment values to radiation resistance in ESCC was significantly better than that of the other pathways.DESeq2 analysis revealed that key molecules in the tryptophan metabolism pathway,namely,IDO1,ALDH1B1,AOC1,INMT,AFMID and ALDH7A1,were significantly differentially expressed in the resistant and sensitive groups of ESCC.Based on the SVM-RFE algorithm,the AUC was 0.77,which could accurately predict the radiotherapy efficacy of ESCC.Western blotting experiments showed that IDO1 was highly expressed in ESCC cells,and IDO1 inhibitor treatment significantly inhibited the survival ability and radiosensitivity of KYSE-410 cells.In the enrolled patients of our hospital,immunohistochemical studies showed that IDO1 was highly expressed in the radiotherapy resistant group of ESCC and was associated with poor radiotherapy prognosis in ESCC patients.In addition,further testing showed that the expression of IDO1 in patient samples from our hospital was positively correlated with its PD-L1 expression,but negatively correlated with the infiltration ratio of CD3/CD8 immune cells.Conclusion Tryptophan catabolism is associated with radiation resistance in ESCC,and the key enzyme IDO1 in tryptophan metabolism can be used as a therapeutic target for radiosensitization in ESCC.

Objective:To explore the anal function and postoperative complications of 2-stage Turnbull-Cutait pull-through coloanal anastomosis (TCA) for low rectal cancer.Methods:Patients undergoing radical rectal cancer resection from Feb 2023 to Nov 2024 in the First Hospital of Jilin University were divided into the TCA surgery group and the low anterior resection combined with prophylactic stoma (LAR) surgery group.Results:Among the 102 patients, there were 50 cases in the TCA group and 52 cases in the LAR group. In the single-arm analysis of the TCA group, the overall complication rate was 44%. The incidence rates of severe LARS at 1 month, 3 months, and 6 months after surgery were 97%, 77%, and 64% respectively. There was no significant difference in the complication rate within 30 days after surgery between the two groups,(44% vs. 38%, χ2=0.135, P>0.05). There was no significant difference in the incidence rate of severe LARS between the TCA group and the LAR group (77% vs. 69%, χ2=0.202, P>0.05), and there was not significant difference in the incidence rate of severe LARS between the two groups at the 6th month after surgery,(64% vs. 48%, χ2=1.132, P>0.05). Conclusion:In patients who underwent TCA surgery, the LARS symptoms gradually decreased over time. Compared with patients undergoing low anterior resection and stoma reversal, there were no significant differences in complications within 30 days after surgery and LARS symptoms within half a year.

Objective To explore the biological mechanism of radiation resistance in esophageal squamous cell carcinoma(ESCC)and search for effective sensitization targets.Methods We retrieved 186 signaling pathways and related gene information from the MSigDB database.We also obtained RNA transcriptome data of ESCC patients using the Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.We collected clinical pathological characteristics and tissue samples of 97 ESCC patients in our hospital from 2013 to 2020.Gene set variation analysis(GSVA)was made to calculate KEGG signaling pathway score,radiotherapy resistance related signaling pathways were screened through random forest algorithm,key genes in the pathway were screened using DESeq2,and a radiotherapy efficacy prediction model was constructed based on support vector machine-recursive feature elimination(SVM-RFE).The results were validated through experiments such as Western blotting and clonogenic assay.Results Based on the KEGG signaling pathway and GSVA enrichment score,random forest analysis showed that in the TCGA and GSE45670 cohorts,the contribution of tryptophan metabolism pathway enrichment values to radiation resistance in ESCC was significantly better than that of the other pathways.DESeq2 analysis revealed that key molecules in the tryptophan metabolism pathway,namely,IDO1,ALDH1B1,AOC1,INMT,AFMID and ALDH7A1,were significantly differentially expressed in the resistant and sensitive groups of ESCC.Based on the SVM-RFE algorithm,the AUC was 0.77,which could accurately predict the radiotherapy efficacy of ESCC.Western blotting experiments showed that IDO1 was highly expressed in ESCC cells,and IDO1 inhibitor treatment significantly inhibited the survival ability and radiosensitivity of KYSE-410 cells.In the enrolled patients of our hospital,immunohistochemical studies showed that IDO1 was highly expressed in the radiotherapy resistant group of ESCC and was associated with poor radiotherapy prognosis in ESCC patients.In addition,further testing showed that the expression of IDO1 in patient samples from our hospital was positively correlated with its PD-L1 expression,but negatively correlated with the infiltration ratio of CD3/CD8 immune cells.Conclusion Tryptophan catabolism is associated with radiation resistance in ESCC,and the key enzyme IDO1 in tryptophan metabolism can be used as a therapeutic target for radiosensitization in ESCC.

Objective:To explore the clinical characteristics and healthcare burden in patients with McCune-Albright syndrome (MAS).Methods:A cross-sectional study was conducted at the Children′s Hospital, Zhejiang University School of Medicine. Clinical and healthcare burden data were systematically collected through structured questionnaires in 164 children with MAS from February 2022 to May 2023. According to the clinical characteristics, patients were categorized into 3 groups: monosymptomatic, bisymptomatic and trisymptomatic groups. Patients were also divided into 3 groups according to the age of <7, 7-<10 and 10-18 years. Comparative analyses of clinical characteristics and healthcare burden were conducted across age, sex, and symptom categories.Results:The cohort comprised 59 males (36.0%) and 105 females (64.0%) with an age of 4.6 (2.0, 7.4) years. Age stratification revealed 117 cases (71.3%) aged 0-<7 years, 29 cases (17.7%) aged 7-<10 years, and 18 cases (11.0%) aged 10-<18 years. Among monosymptomatic (67 cases, 40.9%), the cohort comprised 32 females (47.8%) and 35 males (52.2%), predominantly presenting with fibrous dysplasia (57 cases, 85.1%). This subgroup showed peak prevalence in the 0-<7 years age range (29 cases (50.9%)). The bisymptomatic cohort (56 cases, 34.1%) consisted of 39 females (69.6%) and 17 males (30.4%), predominantly manifesting fibrous dysplasia with skin hyperpigmentation (25 cases, 44.6%). Peak prevalence occurred in the 0-<7 years subgroup(16 cases (64.0%)). The trisymptomatic cohort (41 cases, 25.0%) consisted of 34 females (82.9%) and 7 males (17.1%), with peak prevalence occurring in the 0-<7 years subgroup (36 cases (87.8%)). The diagnostic journey analysis revealed 94 cases (57.3%) required 1-3 referrals, and 34 cases (20.7%) necessitated >3 referrals from symptom onset to definitive diagnosis. Healthcare expenditure analysis revealed 69 families (42.1%) incurred direct medical costs of 10 000-100 000 CNY, with 11 families (6.7%) exceeding >100 000 CNY. Direct non-medical costs reached of 10 000-100 000 CNY for 62 families (37.8%) and >100 000 CNY for 4 families (2.4%). Productivity loss affected 58 families (35.4%) at 10 000-100 000 CNY and 8 families (4.9%) above 100 000 CNY during the study period.Conclusion:MAS requires increased attention to skeletal manifestations, especially in children aged 0-<7 years. Moreover, the significant financial burden on families necessitates a society-wide support system.

Objective:To explore the molecular epidemiological characteristics of human metapneumovirus (HMPV) in children with acute respiratory infection (ARI) in Beijing from 2023 to 2024.Methods:In the longitudinal study, 9 834 children with ARI were enrolled from August 2023 to December 2024, including the influenza-like illness (ILI) group from emergency and outpatient department receiving influenza virus (Flu) and HMPV test and the ARI inpatient group for 13 common respiratory pathogen screening test including HMPV, Flu, respiratory syncytial virus, and so on. All respiratory samples positive with HMPV were genotyped by amplifying and sequencing of G gene and further phylogenetic analysis. The χ2 test and Wilcoxon rank-sum test were used to compare the positive rate and basic clinical data of the 2 groups. Results:Among 9 834 enrolled patient, there were 5 276 male and 4 558 female children, with age 5.4 (1.9, 8.2) years. In ILI group of 1 460 patients, there were 83 cases (5.7%) positive for HMPV, with the age 4.9 (3.6, 6.6) years and children under 6.0 years old 59 cases (71.1%). Among 8 374 ARI inpatients, there were 256 cases (3.1%) positive for HMPV, with age 3.5 (1.3, 6.4) years and children under 6.0 years old 188 cases (73.4%). The HMPV positive rate and the age of children positive for HMPV in ARI inpatient group were significantly lower than that in ILI group (both P<0.001). In December, 2024, the HMPV positive rates of ILI and ARI inpatient group (21.3% (17/80), 15.0% (47/314)) were significantly higher than the total positive rates of each group (both P<0.001). Among 279 subtyped specimens, there were 155 cases (55.6%) belonging to genotype A and 124 cases (44.4%) belonging to genotype B. Sub-lineage A2.2.2 containing 111nt-insertions was predominate one in 2023 with positive ratio 89.2% (91/102), and B2 was predominate in 2024 with positive ratio 64.4% (114/177). Conclusions:From 2023 to 2024, the positive rate of HMPV in the ILI group was higher than that in the ARI inpatient group, suggesting a common epidemic of HMPV infection. Children positive for HMPV in the ARI inpatient group were younger than that in the ILI group. A severe epidemic of HMPV was observed in the winter of 2024, which requires attention. Sub-lineage A2.2.2 with 111nt-duplicate insertions and B2 were the predominant epidemic strains in 2023 and 2024, respectively.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

Objective:To investigate the protective effect of a composite hydrogel against hydrogen peroxide(H2O2)-induced oxidative stress injury in the cardiomyocytes,and to clarify its possible mechanism.Methods:The mice were subcutaneously injected with 100 μL of hydrogel.After normal feeding for 1,14,and 28 d,the mice were sacrificed.Tissue samples were collected and subjected to HE staining to observe the histocompatibity of the hydrogel.The primary cardiomyocytes isolated from 1-day-old SD rats were used to establish an oxidative stress injury model.The primary cardiomyocyties were divided into control,H2O2 and H2O2+Hydrogel groups.The primary cardiomyocytes in control group were cultured normally,the primary cardiomyocytes in H2O2 group were treated with 200 μmol·L-1 H2O2 for 24 h,and the primary cardiomyocytes in H2O2+Hydrogel group were incubated with 1 g·L-1 composite hydrogel and 200 μmol·L-1 H2O2 for 24 h.The viabilities of cardiomyocytes in various groups were assessed by cell counting kit-8(CCK-8)method.Dihydroethidium(DHE)and 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)staining were used to assess the reactive oxygen species(ROS)levels in the cells.The expressions of filamentous actin(F-actin)in the cells in various groups were detected by phalloidin fluorescence staining;the expressions of connexin 43(Cx43)and cardiac troponin T(cTnT)proteins in the cardiomyocytes in various groups were detected by immunofluorescence method.The apoptotic rates of cardiomyocytes in various groups were assessed with TUNEL staining method.The expression levels of apoptosis-related proteins B-cell lymphoma-2(Bcl-2)and Bcl-2-associated X protein(Bax)in the cardiomyocytes in various groups were assessed by Western blotting method.Results:The HE staining results showed that the inflammatory cells around the implanted hydrogel were less infiltrated,and the inflammatory reaction of subcutaneous implantation was less.Compared with control group,the viability of cardiomyocytes in H2O2 group was significantly decreased(P＜0.05),the level of ROS in the cells was increased(P＜0.05),the expression levels of Cx43,cTnT and F-actin proteins in the cells were decreased(P＜0.001),the apoptosis rate of cardiomyocytes were decreased(P＜0.01),the expression level of Bcl-2 protein in the cells was increased(P＜0.001),and the expression level of Bax protein was decreased(P＜0.01).Compared with H2O2 group,the viability of cardiomyocytes was significantly increased(P＜0.05),the level of ROS in the cells was decreased(P＜0.01),the expression levels of cTnT,Cx43 and F-actin proteins were increased(P＜0.01),the apoptotic rate of cardiomyocytes were significantly decreased(P＜0.001),the expression level of Bcl-2 protein in the cells were decreased(P＜0.01),and the expression level of Bax protein was increased(P＜0.01).Conclusion:Hydrogel may promote the expression of cardiomyocyte-related proteins by scavenging ROS in the environment and inhibit the cardiomyocyte apoptosis to achieve the protective effect on the cardiomyocytes under oxidative stress.

Objective:Hearing loss can seriously affect mental health status, and this study aims to investigate the influence of hearing health status on depressive symptoms among middle-aged and older individuals in the community.Methods:From June to December 2023, a stratified random sampling method was employed to select 1 238 community-dwelling middle-aged and elderly people aged 45 years and above from four cities (Hangzhou, Shanghai, Baoding, and Zhengzhou) as research subjects. A questionnaire survey was conducted to collect the subjects′ basic information, hearing health status [assessed by the Hearing Handicap Inventory for Adults-Screening Version (HHIA-S)], and depressive symptoms [assessed by the Geriatric Depression Scale-15 (GDS-15)]. T-tests, rank-sum tests and chi-square tests were used for univariate analysis, while, multiple linear regression and binary Logistic regression were applied to analyze the relationship between hearing health status and depressive symptoms.Results:A total of 1 183 community-dwelling middle-aged and elderly people aged 45 years and above were included in the final analysis (464 males and 719 females, aged from 45 to 96 years). The detection rate of hearing loss was 35.3%(418/1 183), while, the detection rate of depressive symptoms was 9.89%(117/1 183). Age, level of interaction with children, self-rated health, perceived loneliness, and hearing health significantly influenced depressive symptoms among older adults residing in the community ( P<0.05). Individuals with moderate to severe hearing loss ( β=2.04, 95% CI: 1.47, 2.62) exhibited higher GDS-15 scores compared to those without hearing impairment. Furthermore, after correcting for sex, age, marital status, monthly per capita family income, education, residence, smoking status, alcohol use, use of psychotropic medication (anxiolytic or depressant), number of illness, self-health assessment, and autonomy, middle-aged and older adults with mild to moderate hearing loss ( OR=2.89, 95% CI: 1.76, 4.88) and severe hearing loss ( OR=5.79, 95% CI: 3.05, 11.01) demonstrated an increased likelihood of experiencing depression. Conclusions:The degree of hearing loss in community-dwelling middle-aged and elderly individuals is closely associated with the risk of depressive symptoms. Therefore, it is imperative to enhance hearing health screening and to provide mental health support to individuals with hearing loss, in order to mitigate the onset and progression of depressive symptoms.