Type Ⅵ secretion system(T6SS)is a lethal weapon that releases effectors in direct contact to kill eukaryotic predators or prokaryotic competitors.T6SS is of great significance in bacterial environmental adaptability,pathogenicity,and gene horizontal transfer.T6SS has been identified in about 25％of Gram-negative bacteria.Because of its widespread existence,T6SS is considered the key factor of ecological competition.T6SS effectors exerting biological functions have high diversity and do not have conserved sequences,and the regulatory mechanisms involved are complex.Therefore,it is a hot and difficult topic in T6SS research.Vibrio fluvialis(V.fluvialis)as a newly emerging foodborne pathogen,has unique characteristics in the quantity,composition,and physiological function of T6SS,which is related to its wide environmental adaptability and pathoge-nicity.This article mainly reviews the research progress of V.fluvialis T6SS,including its composition,structure,functional activity,and regulatory mechanism.

Aim To investigate the inhibitory effect of ginsenoside Rg1 on sodium palmitate induced fibrosis in human glomerullar mesangial cells (HMCs) and its mechanism. Methods (1) HMCs were treated with different concentrations of PA for 24 h, the intracellular lipid accumulation was observed by oil red staining, and the intracellular ROS production was detected by H2DCFDA kit; (2) HMCs were divided into control, PA (160 μmol·L

Objective:To describe the design, manufacture and use of three-dimensional (3D)-printed endoprosthesis for reconstruction after metaphysis-involved intercalary tumor resection and to evaluate its outcome.Methods:Forty-three patients who received metaphysis-involved intercalary tumor resection followed by 3D-printed endoprosthetic reconstruction in Musculoskeletal Tumor Center, Peking University People's Hospital between January 2018 and December 2021 were retrospectively reviewed. There were 25 males and 18 males with an average age of 20.1±15.2 years (range, 4-58 years). The pathological diagnosis included 24 cases of osteosarcomas, 6 cases of Ewing sarcomas, 5 cases of chondrosarcomas, 2 cases of pleomorphic undifferentiated sarcomas, 3 cases of soft-tissue sarcomas (liposarcoma, synovial sarcoma, malignant peripheral nerve sheath tumor for each) and 3 others (adamantinoma, recurrent aneurysmal bone cyst and recurrent osteofibrous dysplasia for each). The tumors located at femur in 25 patients (58%), including 14 lesions involving distal femoral metaphysis and 11 lesions involving both proximal and distal metaphysis; the tumors located at tibia in 11 patients (26%), including 4 lesions involving distal tibial metaphysis, 5 lesions involving proximal tibial metaphysis and 2 lesions involving both proximal and distal tibial metaphysis; the tumors located at humerus in 7 patients (16%), including 1 lesion involving distal humeral metaphysis, 3 lesions involving proximal humeral metaphysis and 3 lesions involving both proximal and distal humeral metaphysis. The endoprosthesis was designed in a semi-modular fashion and consisted of three parts: a diaphysis-fixing component, a semi-modular lap joint component, and a custom-made 3D-printed metaphysis-fixing component which was designed as two types with 3D-printed porous bone-contacting surfaces according to the osteotomy plane (Type I on meta-diaphyseal region, Type II on meta-epiphyseal region). The functional outcome was assessed using Musculoskeletal Tumor Society (MSTS) 93 system.Results:All surgeries were accomplished sucessfully. The median resection length and the distance from osteotomy plane to adjacent joint was 16.0 (13.0, 22.0) cm and 4.5 (3.5, 6.0) cm, respectively. 59 metaphysis-fixing components were installed in 43 patients. Type I components were used in single and dual ends of endoprosthesis in 12 and 6 cases respectively. Type II components were used in single and dual ends in 15 and 5 cases respectively. Hybrid endoprosthesis with Type I and II components were used in 5 cases. The mean follow-up time was 26.0 (17, 37) months (range, 12-54 months). The mean MSTS 93 score was 29.0 (28.0, 30.0) points (range, 21-30 points). Implant failures were found in 5 patients, including 2 cases of aseptic loosening (loosening was observed in the cementing diaphysis-fixing stems while no evidence of loosening in metaphysis-fixing components) and 3 cases of local tumor progression. The 2-year implant survival rate was 90.3% (95% CI: 0.81, 0.99). Conclusion:Using 3D-printed intercalary endoprosthesis for reconstruction after intercalary resection of metaphysis-involved bone tumor shows satisfactory functional outcome and implant survival. Moreover, by assembling endoprosthetic components according to the different osteotomy plane, the semi-modularized endoprosthesis also provids a comprehensive and individualized reconstruction for patients with metaphysis-involved intercalary tumor.

Objective To investigate the influence of self-efficacy and postoperative pain on postoperative kinesiophobia in aged patients with femoral neck fractures and explore the mediating effect of self-efficacy on postoperative pain and kinesiophobia of the patients.Methods A total of 120 aged patients with femoral neck fractures were included in the study.A cross-sectional study was conducted using general questionaire,the rehabilitation self-efficacy scale,digital pain rating scale and Tampa scale for kinesiophobia.Pearson correlation was used to analyse the correlations between postoperative pain,self-efficacy and postoperative kinesiophobia.AMOS21.0 software was used to establish the mediating effect model of self-efficacy between postoperative pain and postoperative kinesiophobia.The mediating effect was verified by Bootstarp confidence interval evaluation.Results All 120 aged patients with femoral neck fractures completed the study.The score of postoperative kinesiophobia was(40.27±12.85).The level of kinesiophobia was negatively correlated with the self-efficacy score(r=-0.571,P<0.01),and positively with the level of postoperative pain(r=0.766,P<0.01).The direct standardized effect of postoperative pain on postoperative panic level was 0.367,the direct standardized effect of self-efficacy on postoperative panic level was-0.485,the direct standardized effect of postoperative pain on self-efficacy was-0.716,the indirect standardized effect of postoperative pain on postoperative panic level was 0.347,and the total standardized effect was 0.714,accounting for 48.60%of the total effect.Conclusions Postoperative pain can directly affect postoperative kinesiophobia or indirectly affect it via self-efficacy in elderly patients with femoral neck fractures.Medical staff should improve the self-efficacy of the aged patients by relieving the postoperative pain and alleviating the postoperative kinesiophobia.

Objective:To explore the effect of preoperative incentive spirometry combined with active cycle of breathing techniques (ACBT) training on pulmonary function recovery after scoliosis surgery in adolescents.Methods:From June 2019 to June 2021, random sampling was used to select 88 patients with scoliosis admitted to Beijing Chaoyang Hospital affiliated to Capital Medical University as the study subject. The patients were divided into a study group and a control group using a random number table method, with 44 patients in each group. The control group received preoperative ACBT training, while the study group conducted preoperative incentive spirometry combined with ACBT training. The respiratory function and blood gas indicators, including forced expiratory volume (FEV1) , forced vital capacity in one second (FVC) , vital capacity, and blood oxygen saturation (SpO 2) , were compared between the two groups before and two weeks after intervention. The Borg Scale and the Tilburg Frailty Indicator were used to evaluate the degree of dyspnea and physical frailty in the two groups of patients, and the incidence of complications and treatment satisfaction were compared between the two groups to analyze the effect of preoperative incentive spirometry combined with ACBT training on pulmonary function recovery after scoliosis surgery in adolescents. Results:Two weeks after operation, the FEV1/FVC ratio and SpO 2 in the two groups were lower than those before intervention, with a statistical difference ( P<0.05) ; The FEV1/FVC ratio and SpO 2 in the study group were statistically higher than those in the control group ( P<0.01) . The vital capacity of the control group decreased two weeks after operation compared to that before intervention, and the vital capacity of the study group was higher than that of the control group, with statistically significant differences ( P<0.05) . Two weeks after operation, the Borg Scale score of patients in both groups was higher than that before intervention, and that of the study group was lower than that of the control group, with statistically significant differences ( P<0.05) . There was no statistical difference in the incidence of postoperative complications between the two groups ( P>0.05) . The treatment satisfaction in the study group was 97.73% (43/44) , higher than 86.36% (38/44) in the control group, with a statistically significant difference ( P<0.05) . Conclusions:Preoperative incentive spirometry combined with ACBT training can promote postoperative pulmonary function recovery, alleviate frailty symptoms, and improve patient satisfaction in patients with scoliosis, which is worthy of clinical practice.

Taking the Chinese city of Xiamen as an example, simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019 (COVID-19) and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures. A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios. The comparison was conducted between simulated and real cases in Xiamen. A web interface with adjustable parameters, including choice of intervention measures, intervention weights, vaccination, and viral variants, was designed for users to run the simulation. The total case number was set as the outcome. The cumulative number was 4,614,641 without restrictions and 78 under the strictest intervention set. Simulation with the parameters closest to the real situation of the Xiamen outbreak was performed to verify the accuracy and reliability of the model. The simulation model generated a duration of 52 days before the daily cases dropped to zero and the final cumulative case number of 200, which were 25 more days and 36 fewer cases than the real situation, respectively. Targeted interventions could benefit the prevention and control of COVID-19 outbreak while safeguarding public health and mitigating impacts on people's livelihood.
COVID-19/prevention & control* ; China/epidemiology* ; Humans ; Machine Learning ; Pandemics/prevention & control* ; Policy ; Reproducibility of Results ; SARS-CoV-2

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.
COVID-19 ; Cohort Studies ; Contact Tracing ; Humans ; Incidence ; Prospective Studies

ObjectiveTo explore the effect of kinematic alignment on postoperative knee function for patients after total knee arthroplasty (TKA). MethodsFrom June, 2020 to October, 2021, 200 patients undergoing primary TKA in Beijing Chaoyang Hospital were divided into mechanical alignment (MA) group (n = 100) and kinematic alignment (KA) group (n = 100). All the patients accepted comprehensive rehabilitation after operation. They were assessed with Keen Society Score (KSS) before and three months after operation, with Visual Analogue Scale for pain (VAS) before, and three days and three months after operation. The time of first standing, the time of first straight-leg raising more than 30°, and the active range of motion (AROM) of knee before, and one, two and three days, and one and three months after operation were recorded, as well as where to go after discharge. ResultsA total of 96 patients in MA group and 98 in KA group finished the research. The AROM of knee improved more in the KA group than in the MA group after operation (F_group = 8.816, P = 0.017), and the incidence going to the rehabilitation institutes was less (χ² = 6.542, P = 0.011). ConclusionKA may promote the rapid recovery of AROM of knee for patients after TKA, and reduce the needs of institute-based rehabilitation after discharge, to save medical costs.

ObjectiveTo explore the effect of low-fat and low-energy diet on the ultrasound examination of liver， gallbladder and pancreas of participants. MethodsFrom January 2020 to September 2020，a total of 30 participants were enrolled in this study. Using self-controlled research method， firstly， ultrasound scans were performed to them for scanning some organs （such as pancreas， left liver and gallbladder） after fasting more than 8 hours， then the participants were told to eat the low-fat and energy foods （steamed bread and porridge）， and five times of the same ultrasound scans were performed to them at 0.5 h， 1 h， 2 h， 3 h and 4 h after the meal. Every participant was tested in the above 6 groups. The ultrasound images were blindly evaluated， and gallbladder volumes were compared by two sonographers. The single-factor method of repeated measurement was used to evaluate the ultrasound image qualities of different groups and to compare the gallbladder volumes. ResultsThe difference had no statistical significance in imaging quality of pancreas and left liver between each postprandial group and fasting group （P > 0.05）. Among the most concerned gallbladder ultrasound image quality， the difference had no statistical significance between groups （F=0.7， P=0.6）. For the percentage of gallbladder volume， the difference had no statistical significance between groups （F=1.8， P=0.2）. ConclusionCompared with the ultrasound examination under an 8-hour fasting state， the ultrasound images of abdominal organs （such as liver， pancreas and gallbladder） and the gallbladder volumes are not affected by the low-fat and low-energy diets.

Objective:Based on the data of Global Burden of Disease 2019 data, to analyze the past, current, and future burden of disability-adjusted life years (DALYs) in China and compare with the international status.Methods:The total number of DALYs, age-standardized DALY rate, and the composition of different subgroups were extracted and described to analyze the time trend in 2000-2019 and the current situation in 2019 for Chinese female breast cancer. The burden of DALYs in 2050 was predicted by Joinpoint using average annual percent change (AAPC).Results:In 2000-2019, the ranking of DALYs caused by female breast cancer in China rose from the fourth to the second in all female cancers. The total DALYs increased by 48.4%, of which the years lived with disability increased from 4.8% to 8.8%. The age-standardized DALY rate only slightly decreased (AAPC=-0.3%; which increased during 2016-2019, AAPC=1.6%). In 2019, the age-standardized DALY rate for breast cancer in China was 278.0/100 000. The DALYs were 2.88 million (accounting for 14.2% of the global burden and 12.1% of all female cancers burden in China), 26.5% of which attributed known risk factors (overweight and obesity were the largest: 0.34 million DALYs, but some common breast cancer risk factors were not available on the platform, such as menstruation and fertility). In 2050, the prediction suggests that the total DALYs caused by female breast cancer in China will reach 3.80 million person-years-5.16 million person-years, increasing 32.1%-79.4% over 2019. From 2000 to 2019, the peak age of DALYs and DALY rate became older, and the DALYs among females aged 65 years and above increased faster than those younger than 65 years (AAPC were 4.8% and 1.3%, respectively). In 2019, females aged 45-74 (the starting age recommended by local guidelines for breast cancer screening) contributed 74.3% of the total DALYs.Conclusions:Over the past 20 years, the age-standardized DALY rate for breast cancer in female populations in China has not changed obviously. Without the continuous expansion of effective intervention and population aging, the burden of DALYs for female breast cancer in China will increase. DALYs for breast cancer attributed leading risk factors were still limited.