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 explore the association between the HLA antibody positivity rate in female blood donors and pregnancy history, number of pregnancies, interval from the last pregnancy to blood donation, and age, to identify associated variables using a univariate generalized additive model (GAM), and to further analyze the predictive role of characteristic variables for HLA antibody positivity using a random forest model. Methods: HLA antibody detection was performed on 391 female blood donors using the Luminex immunomagnetic bead method. The correlation between pregnancy-related factors and HLA antibodies was analyzed using the Chi-square test. Based on R software, a univariate GAM was first constructed to analyze the association types between characteristic variables and the HLA antibody positivity rate, followed by the construction of a random forest model to evaluate the predictive value of the variables. Results: Among the 391 female blood donors without a transfusion history, the overall HLA antibody positivity rate was 26.34%. The positivity rate in donors with a pregnancy history was significantly higher than that in those without (30.09% vs 9.72%, P<0.05), and HLA antibody positivity rate increased linearly with the number of pregnancies (P<0.05). In the univariate GAM, age and number of deliveries exhibited a non-linear association with the HLA antibody positivity rate (the positivity rate increased sharply between 25-35 years of age and stabilized after 3 deliveries). Besides, the interval from the last pregnancy to blood donation showed a linear association with the HLA antibody positivity rate, and the positivity rate decreased as the interval prolonged (P<0.05). In the random forest model, age (mean decrease gini=29.26) and interval from the last pregnancy to blood donation (mean decrease gini=22.02) were core predictive variables: age was more conducive to identifying positive samples, while the interval from the last pregnancy to blood donation was more helpful for excluding negative samples. The number of deliveries (mean decrease accuracy=16.98) made a significant contribution to predicting positive samples, whereas the number of abortions had no impact. The model had an AUC of 0.583 (95% CI: 0.593 8-0.770 2), indicating a certain predictive value. Conclusion: The associated variables identified by the univariate GAM model, including age, interval from the last pregnancy to blood donation, and number of deliveries, provide a basis for key variables in the random forest model. All three variables have predictive value for HLA antibody positivity, which can provide evidence-based support for personalized transfusion management and stratified screening of female blood donors in this region.

Ferroptosis is a key driver of the onset and progression of chronic obstructive pulmonary disease （COPD）. By exploring the role of ferroptosis in COPD from the perspective of "qi deficiency with retention and stagnation"， it is considered that mitochondrial dysfunction and imbalanced antioxidant defenses are the microscopic manifestations of "qi deficiency"， whereas iron accumulation and lipid peroxide deposition constitute the pathological basis of "retention and stagnation". In traditional Chinese medicine （TCM）， the treatment principle is tonifying deficiency and benefiting qi， scattering retention and unblocking stagnation. Its mechanism involves improving the antioxidant system and mitochondrial function to enhance cellular resistance to ferroptosis， as well as relieving pulmonary iron overload， excessive lipid peroxidation， and inflammatory factor release to reduce the accumulation of pathological products， thereby exerting therapeutic effects on COPD.

ObjectiveTo investigate the syndrome evolution patterns， characteristics of the used herbal medicinals， and efficacy variations across different stages of rheumatoid arthritis （RA） progression. MethodsBased on the China Rheumatoid Arthritis Registry of Patients with Chinese Medicine （CERTAIN）， 2,506 RA patients were retrospectively enrolled and categorized into ＜6 months group （166 cases）， 6 months to ＜5 years group （1063 cases）， 5 to ＜20 years group （1067 cases）， and ≥20 years group （210 cases）. Syndromes were differentiated before and after traditional Chinese medicine （TCM） treatment， including damp-heat obstruction， wind-damp obstruction， cold-damp obstruction， blood stasis obstructed in the collaterals， phlegm-stasis obstruction， liver-kidney insufficiency， qi and blood deficiency， and qi-yin deficiency. The syndrome evolution rate was calculated for high-frequency syndromes before and after treatment. Analysis was conducted on top 20 frequently used Chinese herbs at the first diagnosis. Clinical efficacy of the 28-joint disease activity score based on erythrocyte sedimentation rate （DAS28-ESR） and 28-joint disease activity score based on C-reactive protein （DAS28-CRP） before and after treatment were assessed. A multivariate logistic regression analysis was performed to identify factors affecting the efficacy of TCM treatment. ResultsPatients with course of disease shorter than 6 months predominantly presented with cold-dampness obstruction syndrome （49/166， 29.5%）， wind-dampness obstruction syndrome （46/166， 27.7%）， and dampness-heat obstruction syndrome （43/166， 25.9%）. For patients with course of disease logner than 6 months and shorter than 5 years and those within 5 to 20 years， the dominant syndrome was dampness-heat obstruction syndrome （324/1063， 30.5% and 318/1067， 29.8%， respectively）. In patients with disease duration ≥20 years， liver-kidney insufficiency syndrome and dampness-heat obstruction syndrome both predominated， each accounting for 25.24% （53/210）. The syndromes with more than 100 cases before treatment and a syndrome evolution rate greater than 10% after treatment were dampness-heat obstruction （201/738， 27.2%）， liver-kidney insufficiency （119/367， 32.4%）， and phlegm-stasis obstruction syndromes （73/172， 42.4%）. These were classified as high-frequency syndromes. After treatment， damp-heat obstruction syndrome and liver-kidney insufficiency syndrome primarily evolved into wind-damp obstruction syndrome， while phlegm-stasis obstruction syndrome evolved into damp-heat obstruction and cold-damp obstruction syndrome. The top two commonly used Chinese herbs across all groups were Gancao （Radix et Rhizoma Glycyrrhizae） and Baishao （Radix Paeoniae Alba）. In the ＜6 months group and the 6 months to ＜5 years group， high-frequency herbs also included Fangfeng （Radix Saposhnikoviae）， Duhuo （Radix Angelicae Pubescentis）， Chuanxiong （Rhizoma Chuanxiong）， and Qianghuo （Radix et Rhizoma Notopterygii）. In the 5 to ＜20 years group and the ≥20 years group， the usage of Huangqi （Radix Astragali）， Fuling （Poria）， Niuxi （Radix Achyranthis Bidentatae）， and Danggui （Radix Angelicae Sinensis） increased， while the proportion of Fangfeng and Duhuo decreased. After treatment， the DAS28-ESR and DAS28-CRP scores in all groups significantly decreased （P＜0.05）. There were statistically significant differences in clinical efficacy based on DAS28-ESR and DAS28-CRP across all groups （P＜0.01）. Multivariate logistic regression revealed significantly reduced treatment efficacy in the 6 months-5 years group （OR=0.4）， 5~20 years group （OR=0.5）， and ≥20 years group （OR=0.4） compared to the ＜6 months group. ConclusionRA syndromes follow a progression pattern from excess to deficiency， with corresponding transition in herbal usage from pathogen-eliminating to healthy qi-reinforcing approaches. TCM intervention can significantly reduce disease activity of RA， with superior efficacy in patients with disease duration shorter than 6 months.

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:To investigate the preventive and therapeutic effects and mechanisms of Dachaihu decoction(DCD)on dextran sodium sulfate(DSS)-induced ulcerative colitis(UC)and liver injury in mice,as well as the association between DCD benefits and gut microbiota modulation.Methods:Mice were treated with DCD(20.10 and 10.05 g/kg)for 2 weeks,with free access to drinking water containing 3%DSS in the second week to induce UC.Histopathological examination,RT-qPCR and 16S rRNA sequencing were used to investigate the effect of DCD on UC mice.Results:DCD pretreatment significantly alleviated weight loss,bloody diarrhea with mucus,histopathological abnormalities of the colon,and colon shortening in mice with DSS-induced UC.In addition,DCD pretreat-ment significantly upregulated the levels of Occludin,ZO-1,and MUC-2 in the colon and protected the intestinal barrier of mice.DCD pretreatment also alleviated inflammatory cell infiltration in the colon and the liver and significantly reduced the expression levels of the proinflammatory factors such as IL-1β,IL-6,TNF-α,iNOS,COX-2,and NLRP3,thereby exerting a protective effect against UC and liver injury.It should be noted that DCD corrected gut micro-biota imbalance in UC mice by enriching probiotic bacteria such as Lactobacillus and Bifidobacterium and reducing harmful bacteria such as Norank_f_Desulfovibrionaceae and Escherichia-Shigella.Conclusion:DCD can alleviate DSS-induced UC and exert a liver-protecting effect by protecting intestinal barrier,inhibiting inflam-mation,and regulating gut microbiota.

At present, acute brain injuries such as stroke and traumatic brain injury have become a serious burden on public health due to relatively limited treatment methods. As an emerging three-dimensional cell culture model, cerebral organoid can well redisplay the cellular diversity, tissue structure and functional characteristics of the human brain, providing an ideal platform for disease modeling, drug development and regenerative medicine research of acute brain injury. However, the construction and application of cerebral organoid are still in the exploratory stage at present, facing major technical bottlenecks such as insufficient vascularization, lack of immune microenvironment and tissue heterogeneity. This review summarizes the cultivation technique of cerebral organoid, highlights its application in acute brain injury, and analyzes its current technical bottleneck, so as to provide more reference basis for the development and application of this technology.

Objective To explore the value of cranial CT perfusion imaging(CTP)parameters combined with head and neck CT angiography(CTA)in assessing collateral circulation status and predicting prognosis in acute ischemic stroke(AIS).Methods A retrospective analysis was carried out on 83 AIS patients who were treated in Taikang Xianlin Drum Tower Hospital from June 2018 to June 2023.CTP and head and neck CTA examinations were performed within 24 hours after admission.Digital subtraction angiography is the gold standard for assessing collateral circulation status in AIS patients.The general information of these patients was collected,and the patient's prognosis was evaluated using the modified Rankin scale through telephone or outpatient follow-up 90 days after the occurrence of AIS.Pearson or Spearman correlation was used to analyze the correlation between collateral circulation assessment and CTP parameters and head and neck CTA scores.The value of CTP parameters and head and neck CTA scores in predicting the prognosis of AIS patients was discussed using multivariate Logistic regression.Moreover,the receiver operating characteristic(ROC)curve was used to analyze the predictive value of CTP parameters,head and neck CTA,and the combination for the prognosis of AIS patients.Results The cerebral blood volume(CBV),cerebral blood flow(CBF),and CTA score were higher,while mean transit time(MTT)and time to peak(TTP)were shorter in the good collateral circulation group than in poor collateral circulation group(P<0.05).The collateral circulation status in AIS patients was negatively correlated with CBV,CBF,and CTA score,while positively correlated with MTT and TTP(P<0.05).Compared with poor prognosis group,good prognosis group had higher CBV,CBF,CTA,and shorter MTT and TTP(P<0.05).Multivariate Logistic regression analysis identified MTT and TTP as risk factors for poor prognosis,and CBV,CBF,and CTA scores as protective factors for poor prognosis in AIS patients(P<0.05).The ROC results showed that the area under the curve(AUC)of CBV,MTT,CBF,TTP,CTA score and the combination to predict the prognosis of AIS patients were 0.897,0.864,0.835,0.920,0.918,and 0.979,respectively,showing better predictive performance of the combination than single index alone(Z=2.194,2.910,2.521,2.229,2.171;P<0.05).Conclusion CTP parameters combined with CTA may effectively assess collateral circulation in patients with AIS and is significant for prognosis prediction.

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 differences in acute intestinal injury and regulatory mechanisms in mice following carbon ion FLASH radiotherapy (FLASH-RT) and conventional dose rate radiotherapy (CONV-RT).Methods:Healthy C57BL/6J mice were randomly divided into three groups: control group, FLASH-RT group (100 Gy/s), and CONV-RT group (0.1 Gy/s), with 9 mice in each group. All mice received carbon ion whole abdominal radiotherapy. DNA double-strand breaks (DSB) and cell proliferation were evaluated by measuring the expression of phosphorylated histone H2AX (γ-H2AX) and nuclear-associated antigen 67 (Ki67) using immunohistochemistry; apoptosis was analyzed using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL); transcriptome sequencing was used to analyze the differences in molecular pathways between FLASH-RT and CONV-RT.Results:Compared with the CONV-RT group, the FLASH-RT group showed significantly reduced intestinal γ-H2AX signal at 3 h after radiotherapy ( t=3.80, P<0.01), significantly increased expression of Ki67 at the base of intestinal crypts at 6 h after radiotherapy ( t=4.30, P<0.001), and a significantly decreased number of TUNEL-positive cells at 12 h after radiotherapy ( t=3.08, P<0.01). Transcriptome sequencing analysis showed that FLASH-RT specifically activated the insulin-like growth factor (IGF) pathway, avoiding the excessive activation of CONV-RT-induced nuclear factor-κB and B cell receptor inflammatory pathways as well as the inhibition of energy metabolism. Conclusions:Compared with CONV-RT, carbon ion FLASH-RT can reduce DSB damage, preserve the proliferative activity of intestinal stem cells, activate the IGF pathway, and regulate inflammatory, immune, and metabolic pathways, thereby significantly alleviating acute intestinal epithelial injury. Specifically, the regulation of repair pathways mediated by reduced DSB and the inhibition of inflammatory pathways are potential protective mechanisms for normal tissues.