The non-structural protein 5(NS5)is a highly conserved protein in the Flavivirus genus,acting as both a methyltransferase(MTase)and an RNA-dependent RNA polymerase(RdRp).It has been well documented that NS5 plays a crucial role in the replication of viral RNA.Recent studies have shown that NS5 proteins from different flaviviruses interact with various proteins in host cells,aiding the virus in evading the immune system.This review summarizes the structure,subcellular localization,and function of NS5 proteins.Additionally,we outline how flavivirus NS5 proteins contribute to viral replication and immune evasion.Lastly,we present the recent developments of specific small molecule inhibitors that target NS5 proteins.

Objective To investigate the knowledge, attitudes and practices (KAP) towards scrub typhus control and analyse the influencing factors among residents in Longling County, Yunnan Province in 2023, so as to provide insights into management of scrub typhus in the county. Methods Two townships were randomly sampled from Longling County, Baoshan City, Yunnan Province in July 2023, and 2 to 3 administrative villages were randomly selected from each township. Then, 20 to 40 households were randomly selected from each village, and 1 to 2 villagers were surveyed in each household. Residents’ KAP towards scrub typhus control was investigated, and factor affecting residents’ KAP towards scrub typhus control were identified with independent samples t test or analysis of variance (ANOVA) and multiple linear regression analysis. Results A total of 417 questionnaires were allocated, and 410 valid questionnaires were recovered, with an effective recovery rate of 98.32%. Of all respondents, 65.85% (270/410) heard of scrub typhus but were not familiar with it, and 12.68% (52/410) and 1.95% (8/410) were familiar and very familiar with it, respectively. Residents mainly acquired scrub typhus control knowledge via their relatives and friends. The knowledge, attitude, and behavior scores of the respondents with regard to scrub typhus were (34.14 ± 13.07), (55.04 ± 6.69), and (21.40 ± 5.61), respectively, and the total score for knowledge, belief, and behavior in relation to scrub typhus prevention and control was (110.57 ± 18.80). Univariate analysis revealed that age (F = 3.12, P < 0.05), education (F = 10.77, P < 0.05), occupation (F = 4.89, P < 0.05), frequency of outdoor activities (F = 3.61, P < 0.05), and type of place of residence (t = 1.33, P < 0.05) were the factors that influenced the participants’ scores for knowledge of the prevention and control of scrub typhus. Multiple linear regression analysis revealed that literacy level (β = 10.20 to 16.71, P < 0.05) and category of residence (β = −7.23, P < 0.05) were the factors that influenced residents’ current knowledge and trust behavior in relation to scrub typhus. Conclusions Place of residence and educational level are critical factors affecting scrub typhus control among residents in Longling County, Yunnan Province. Intensified health education pertaining to scrub typhus control and appropriate behavioral interventions are required among residents living in urban areas, with a low educational level and frequent outdoor activities.

Objective To construct a deep learning-based artificial intelligence model to automatically quantify left ventricular ejection fraction (LVEF) using static views of echocardiography. Methods The study included data of 1, 902 adults with left ventricular multi-slice echocardiographic views at end-systole and end-diastole. The collected dataset was divided into development set (1, 610 cases, with 1, 252 cases for model training and 358 cases for parameter adjustment), internal test set (177 cases for internal validation), and external test set (115 cases for external validation and generalization testing). The model achieved left ventricular segmentation and automatic quantification of LVEF through precise identification of the left ventricular endocardial boundary and inspection of key points. The Dice coefficient was employed to evaluate the performance of the left ventricular segmentation model, while the Pearson correlation coefficient and the intraclass correlation coefficient were used to assess the correlation and consistency between the automatically measured LVEF and the reference standard. Results The left ventricular segmentation model performed well, with Dice coefficients ≥ 0.90 for both the internal and external independent test sets; the agreement between the automatically measured LVEF and the cardiologists' manual measurements was moderate, with Pearson correlation coefficients ranging from 0.46 to 0.71 and intragroup correlation analysis agreements from 0.39 to 0.57 for the internal test set; and Pearson correlation coefficients for the independent external test set were 0.26 to 0.54 and intra-group correlation analysis agreement of 0.23 to 0.50. Conclusion In this study, a left ventricular segmentation model with better performance is constructed, and initial application of the model for automatic quantification of LVEF for two-dimensional echocardiography has general performance, which requires further optimisation of the algorithm to improve the model generalisation.

Objective:To form the expert consensus on screening and evaluation of dysphagia with oral cancer patients (abbreviated as Consensus) , so as to standardize the relevant contents of screening and evaluation of dysphagia in the whole cycle of oral cancer. Methods:By referring to domestic and foreign literature related to dysphagia, combining with the specialty characteristics of oral cancer and the clinical experience of experts, a preliminary consensus was formed through in-depth interviews with experts. A total of 21 experts were selected for three rounds of expert letter consultation and expert meeting, the corresponding items were sorted out, analyzed and modified based on expert opinions, and the Consensus was finally formed. Results:The effective recovery rates of the three rounds of correspondence were 100.00% (21/21) , the expert authority coefficient was 0.91, the variation coefficient of each item was 0.04-0.20, and Kendall's harmony coefficient was 0.05 ( P<0.05) . The final consensus included four aspects, such as the effect of oral cancer on swallowing, the clinical manifestations of dysphagia, the basic procedures of screening and evaluation and the prevention and treatment of complications during evaluation. Conclusions:This Consensus is scientific and practical, which can provide clinical guidance for the screening and evaluation of dysphagia in the whole cycle of oral cancer.

ObjectiveTo investigate the efficacy of Bushen Shengxue prescription and Yiqi Yangxue prescription in the treatment of chronic aplastic anemia and the effect on T cell subsets and the expression of T-box expressed in T cells （T-bet） and GATA binding protein 3 （GATA3）. MethodA total of 585 patients with chronic aplastic anemia who were treated in 19 hospitals in China from May 2018 to June 2021 were enrolled. With the prospective， double-blind and randomized control methods， the patients were randomized into three groups： kidney deficiency group， Qi and blood deficiency group， and control group. The three groups were respectively treated with Bushen Shengxue prescription granule， Yiqi Yangxue prescription granule， and Placebo （half the dose of Bushen Shengxue formula granules）. In addition， all of them were given oral cyclosporin and androgen. The treatment lasted 6 months， with 3 months as a course. The blood routine indexes， T cell subsets， and fusion genes T-bet and GATA3 before and after treatment were analyzed， and the safety indexes were monitored. ResultDuring the observation， a total of 75 cases dropped out and 18 were rejected. Finally， 161 cases in the kidney deficiency group， 164 in the Qi and blood deficiency group， and 167 in the control group were included. After 6 months of treatment， the total effective rate was 98.8% （159/161） in the kidney deficiency group， which was higher than the 79.9% （131/164） in the Qi and blood deficiency group （χ²=30.135， P<0.01） and the 61.7% （103/167） in the control group （χ²=70.126， P<0.01）. The total effective rate was higher in the Qi and blood deficiency group than in the control group （χ²=13.232， P<0.01）. After treatment， the hemoglobin （HGB） content increased significantly in three groups （P<0.05） as compared with that before treatment， particularly the kidney deficiency group （P<0.01）. After treatment， the white blood cell （WBC） count and platelet （PLT） count in the kidney deficiency group and the control group increased compared with those in the Qi and blood deficiency group （P<0.01）. There was no specific difference in neutrophils （ANC） after treatment among the three groups. At the same time point， the level of T helper type 1 （Th1） cells， Th1/Th2 ratio （P<0.05）， level of CD4⁺， and CD4⁺/CD8⁺ ratio （P<0.05） were significantly low in the kidney deficiency group among three groups. There was no significant difference in CD19^-， HLA/DR⁺， and CD25⁺ between the kidney deficiency group and the other two groups， but the T-bet of the kidney deficiency group and the control group was lower than that of the Qi and blood deficiency group （P<0.05）. ConclusionBushen Shengxue prescription exerts therapeutic effect on the aplastic anemia by improving the immunoregulatory mechanism， inhibiting the activity of immune system， modulating T cell subsets， suppressing Th1 and CD4⁺， and promoting bone marrow hematopoiesis. Moreover， it is safe with little side effects， which is worthy of further promotion.

Objective:To investigate the workflow, efficacy and safety of MR-Linac in liver malignancies.Methods:Clinical data of 15 patients with hepatocellular carcinomas (HCC) or liver metastases treated with MR-Linac between November 2019 and July 2021 were retrospectively analyzed. The workflow of MR-Linac was investigated and image identification rate was analyzed. Patients were followed up for response and toxicity assessment.Results:Fifteen patients (6 HCC, 8 liver metastases from colorectal cancer, 1 liver metastasis from breast cancer) were enrolled. A total of 21 lesions were treated, consisting of 10 patients with single lesion, 4 patients with double lesions and 1 patient with triple lesions. The median tumor size was 2.4 cm (0.8-9.8 cm). The identification rate for gross tumor volume (GTV) in MR-Linac was 13/15. Although GTV of two patients were unclearly displayed in MR-Linac images, the presence of adjacent blood vessel and bile duct assisted the precise registration. All the patients were treated with stereotactic body radiation therapy (SBRT). For HCC, the median fraction dose for GTV or planning gross tumor volume (PGTV) was 6 Gy (5-10 Gy) and the median number of fractions was 9(5-10). The median total dose was 52 Gy (50-54 Gy) and the median equivalent dose in 2 Gy fraction (EQD 2Gy) at α/ β= 10 was 72 Gy (62.5-83.3 Gy). For liver metastases, the median fraction dose for GTV or PGTV was 5 Gy (5-10 Gy) and the median number of fractions was 10(5-10). The median total dose was 50 Gy (40-50 Gy) and the median EQD 2Gy at α/ β=5 was 71.4 Gy (71.4-107.1 Gy). At 1 month after SBRT, the in-field objective response rate (ORR) was 8/13 and the disease control rate was 13/13. At 3-6 months after SBRT, the in-filed ORR was increased to 6/6. During the median follow-up of 4.0 months (0.3-11.6), 4-month local progression-free survival, progression-free survival and overall survival were 15/15, 11/15 and 15/15, respectively. Toxicities were mild and no grade 3 or higher toxicities were observed. Conclusions:MR-Linac provides a platform with high identification rates of liver lesions. Besides, the presence of adjacent blood vessel and bile duct also assists the precise registration. It is especially suitable for liver malignancies with promising local control and well tolerance.

Objective:To compare the outcomes of watch&wait (W&W) strategy in patients with locally advanced rectal cancer who achieved complete clinical response (cCR) after neoadjuvant therapy, with those who obtained pathological complete response (pCR) after total mesorectal excision (TME).Methods:This is a retrospective cohort analysis study. Patients histologically proven with locally advanced rectal adenocarcinoma (stage Ⅱ-Ⅲ) who had received neoadjuvant chemotherapy were eligible between January 2014 and December 2019. In whom we included patients who had cCR offered management with W&W strategy after completing neoadjuvant therapy and follow-up ≥1 year (W&W group), and patients who did not have cCR but pCR after TME (pCR group). The primary endpoints were 3-year and 5-year overall survival (OS), colostomy-free survival (CFS), disease-free survival (DFS), non-local regrowth disease-free survival (NR-DFS), and organ preservation rate. Kaplan-Meier analysis was used for survival analysis and log-rank test was performed. For comparative analysis, we also derived one-to-one paired cohorts of W&W versus pCR using propensity-score matching (PSM).Results:A total of 118 patients were enrolled, 49 of whom had cCR and managed by W&W, 69 had pCR, with a median follow-up period of 49.5 months (12.1-79.9 months). No difference was observed in the 3-year OS (97.1% vs. 96.7%) and 5-year OS (93.8% vs. 90.9%, P=0.696) between the W&W and pCR groups. Patients managed by W&W had significantly better 3-year and 5-year CFS (89.1% vs. 43.5%, P<0.001), better 3-year DFS (83.6% vs. 97.0%) and 5-year DFS (83.6% vs. 91.2%, P=0.047) compared with those achieving pCR. The 3-year NR-DFS (95.9% vs. 97.0%) and 5-year NR-DFS (92.8% vs. 97.0%, P=0.407) did not significantly differ between the W&W and pCR groups. Local regeneration occurred in six cases, and 87.7% of patients had successful rectum preservation in the W&W group. In the PSM analysis (34 patients in each group), absolutely better CFS (90.1% vs. 26.5%, P<0.001) was noted in the W&W group. A median interval of 17.5 weeks was observed for achieving cCR, while only 23.9% of patients achieved cCR within 5 to 12 weeks from radiation completion. Patients with short-course sequential chemoradiotherapy achieved cCR significantly later when compared with those with long-course concurrent chemoradiotherapy (19.0 vs. 9.8 weeks, P<0.001). Conclusions:The oncological outcomes of W&W strategy in patients with locally advanced rectal cancer are safe and effective, significantly improving the quality of life. Longer interval for cCR evaluation may improve rectal organ preservation rate.

Objective:To analyze the prognostic factors of breast cancer patients with isolated chest wall recurrence (ICWR) after mastectomy, and investigate the optimal treatment.Methods:A total of 201 breast cancer patients with ICWR after mastectomy who were treated in Cancer Hospital, Chinese Academy of Medical Sciences and the Fifth Medical Center Chinese PLA General Hospital from October 1998 to April 2018 were retrospectively analyzed. The median follow-up was 92.8 months and survival data were obtained.Results:Among 201 patients with ICWR, 103 patients developed subsequent locoregional recurrence (sLRR) and 5-year cumulative sLRR rate was 49.1%; 134 patients developed distant metastasis (DM) and 5-year DM rate was 64.4%; 103 patients died, the median progression-free survival (PFS) was 17.4 months and the 5-year PFS rate was 23.2%; the median overall survival (OS) was 62.5 months and the 5-year OS rate was 52.1%. Multivariate analysis showed that the recurrence interval ( HR=2.17, 95% CI: 1.26-3.73) and the locoregional treatment ( HR=1.59, 95% CI: 1.05-2.40) were the independent prognostic factors for sLRR. The initial HER2 status ( HR=1.60, 95% CI: 1.03-2.48) was the independent prognostic factor for DM. The recurrence interval ( HR=1.99, 95% CI: 1.30-3.04), the locoregional treatment ( HR=1.99, 95% CI: 1.43-2.76) and the treatment modalities after recurrence ( HR=1.70, 95% CI: 1.18-2.46) were the independent prognostic factors for PFS. The initial HER2 status ( HR=1.69, 95% CI: 1.02-2.81), the recurrence interval ( HR=1.85, 95% CI: 1.15-2.98) and the treatment modalities after recurrence ( HR=2.48, 95% CI: 1.56-3.96) were the independent prognostic factors for OS. Conclusions:Breast cancer patients after ICWR have an optimistic OS until now, but the risk of sLRR and DM is high. Comprehensive treatment modalities including surgery, radiotherapy and systemic therapy improve the outcome of breast cancer patients with ICWR after mastectomy.

Objective:To evaluate the clinical efficacy of radiotherapy in the treatment of extracranial metastatic breast cancer, and to investigate the significance and prognostic factors of whole-lesion radiotherapy (WLRT).Methods:Clinical data of 85 patients with extracranial metastatic breast cancer treated with radiotherapy between 2014 and 2019 were retrospectively analyzed. Thirty-six patients were assigned into the WLRT group and 49 in the non-WLRT group. The local control (LC), progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan- Meier method, log-rank test and univariate prognostic analysis. Cox proportional hazards model was used for multivariate prognostic analysis. Results:The median follow-up time was 26.7 months. The 2-year LC, PFS, OS rates were 77%, 26%, 77%, respectively. The 2-year LC (91% vs. 67%, P=0.001), PFS (47% vs. 8%, P<0.001), OS rates (84% vs. 71%, P=0.010) in the WLRT group were significantly higher than those in the non-WLRT group, respectively. Multivariate analysis demonstrated that WLRT was an independent favorable prognostic factor for the LC, PFS and OS. Furthermore, bone metastasis alone was associated with improved LC and positive hormone receptor status was correlated with improved OS. Conclusions:WLRT has the potential to prolong the survival of patients with extracranial metastatic breast cancer. The patients with bone metastases alone obtain better LC, whereas those with negative hormone receptor status has worse OS.

Objective:To investigate the relationship between gastric filling status and intra-or inter-fractional tumor displacement in patients with adenocarcinoma of the esophagogastric junction (AEG) undergoing preoperative radiotherapy.Methods:From October 2018 to June 2019, 10 patients with locally advanced AEG who received totally neoadjuvant therapy were enrolled in this prospective study. Patients received two markers implanted at the cranial and caudal borders of the tumors under gastroscope and a total of 20 fiducial markers were implanted finally. All patients underwent 4DCT scan under the gastric fasting and filling status. Ten images of 0% to 90% respiratory phase were automatically reconstructed by the system (Pinnacle 3, version 9.1, Philips Medical Systems, Eindhoven, The Netherland). Each patient obtained one hundred sets of images. Results:In the tumors proximal to the chest, gastric filling did not significantly affect intrafractional or interfractional tumor displacements. Nevertheless, in the tumors distal to the chest, the interfractional displacement in the cranio-caudal (CC) direction under the gastric fasting status was significantly larger compared with that under the gastric filling status (6.22±4.67 mm vs. 4.13±3.68 mm, P=0.013). To ensure 95% of the prescribed dose irradiated to at least 90% of the tumor volume during the radiotherapy, the margins of tumors proximal to the chest in the left-right (LR), antero-posterior (AP) and CC directions were 9 mm, 8.5 mm, 12.1 mm under gastric filling status with 300 ml semi-fluid. Six patients diagnosed with gastric cancer with proximal thoracic fiducial markers treated by preoperative radiotherapy were included in the validation group, revealing that the fiducial markers of 93% patients were covered in this margin. Conclusion:During the preoperative radiotherapy in AEG patient, the approach of quantitative gastric filling can be considered.