[To discuss the minimally invasive glaucoma surgery related to trabeculotomy from the perspective of physiological function of trabecular meshwork drainage pathway]

The advent of minimally invasive glaucoma surgery (MIGS) has broadened the therapeutic options for managing glaucoma. In recent years, MIGS procedures targeting the trabecular meshwork-Schlemm's canal aqueous outflow resistance site have garnered significant attention. This focus has extended to the pathophysiological changes occurring within the aqueous outflow pathway. However, questions persist regarding the efficacy of near-peripheral or peripheral trabeculotomy in achieving the anticipated reduction of outflow resistance and the suitability of MIGS surgery for patients with primary open-angle glaucoma. By integrating clinical experience with pertinent clinical research, this paper advocates for a reevaluation of MIGS procedures to aid clinicians in making informed decisions regarding various glaucoma surgical interventions.

Construction of a grpE-based plasmid addiction system in Escherichia coli and its application in phloroglucinol biosynthesis

AIM

Biotechnical processes in Escherichia coli often operate with artificial plasmids. However, these bioprocesses frequently encounter plasmid loss. To ensure stable expression of heterologous genes in E. coli BL21(DE3), a novel plasmid addiction system (PAS) was developed.

METHODS AND RESULTS

This PAS employed an essential gene grpE encoding a cochaperone in the DnaK-DnaJ-GrpE chaperone system as the selection marker, which represented a chromosomal ΔgrpE mutant harboring episomal expression plasmids that carry supplementary grpE alleles to restore the deficiency. To demonstrate the feasibility of this system, it was implemented in phloroglucinol (PG) biosynthesis, manifesting improved host tolerance to PG and increased PG production. Specifically, PG titer significantly improved from 0.78 ± 0.02 to 1.34 ± 0.04 g l-1, representing a 71.8% increase in shake-flask fermentation. In fed-batch fermentation, the titer increased from 3.71 ± 0.11 to 4.54 ± 0.10 g l-1, showing a 22.4% increase. RNA sequencing and transcriptome analysis revealed that the improvements were attributed to grpE overexpression and upregulation of various protective chaperones and the biotin acetyl-CoA carboxylase ligase coding gene birA.

CONCLUSION

This novel PAS could be regarded as a typical example of nonanabolite- and nonmetabolite-related PAS. It effectively promoted plasmid maintenance in the host, improved tolerance to PG, and increased the titer of this compound.

[Effects of different types of intraocular lens implantation on patient's visual quality and function after phacoemulsification]

Objective: To explore the effects of different types of intraocular lens (IOL) implantation on patient's visual quality and function after phacoemulsification. Methods: The clinical data of patients with monocular cataract who underwent phacoemulsification in the Department of Ophthalmology, People's Hospital Affiliated to Shandong First Medical University between December 2021 and May 2023 were retrospectively analyzed. According to the types of IOL, the patients were divided into monofocal group, bifocal group and depth of focus extension group. Three months later, uncorrected distance visual acuity (UCDVA), best corrected distance visual acuity (BCDVA), uncorrected intermediate visual acuity (UCIVA), best corrected intermediate visual acuity (BCIVA), uncorrected near visual acuity (UCNVA) and best corrected near visual acuity (BCNVA) were detected. Contrast sensitivity and total wavefront aberration were measured by visual function analyzer. Satisfaction with visual quality was evaluated by hospital-made satisfaction questionnaire. Results: A total of 92 patients were included, with 31 males and 61 females, and their age was (61.8±5.2) years. There were 43, 28 and 21 cases in monofocal group, bifocal group and depth of focus extension group, respectively. No statistically significant difference was found in clinical baseline data among the three groups. UCIVA, UCDVA, BCIVA and BCDVA in depth of focus extension group were 1.01±0.13, 0.92±0.18, 1.21±0.19 and 1.20±0.23, respectively, which were higher than those in monofocal group (0.62±0.12, 0.74±0.13, 1.02±0.17, 1.07±0.19, respectively) and bifocal group (0.67±0.15, 0.78±0.14, 1.01±0.16, 1.01±0.18, respectively), while absolute value of spherical equivalent [(-0.42±0.07) D] was lower than that in the other two groups [ (-0.49±0.05) D and (-0.45±0.08) D] (both P<0.05). UCNVA and BCNVA in bifocal group were 0.91±0.18 and 1.25±0.18, which were higher than those in depth of focus extension group (0.63±0.24 and 1.19±0.17) (both P<0.05). There were no significant differences in contrast sensitivity among the three groups under day vision or between monofocal group and bifocal group under night vision (all P>0.05), but the contrast sensitivity was higher in depth of focus extension group under night vision (3.0, 6.0, 12.0 c/d) than other two groups (all P<0.05). The score of ocular discomfort was the highest in bifocal group, followed by depth of focus extension group and monofocal group (both P<0.05). The score of visual interference in bifocal group was lower than that in monofocal group and depth of focus extension group (both P<0.05). The scores of subjective feeling in bifocal group and depth of focus extension group were higher than that in monofocal group (both P<0.05). The reading score was the highest in bifocal group, followed by depth of focus extension group and monofocal group (both P<0.05). There was no significant difference in total low-order aberration among the three groups (P=0.472). The total aberration and higher-order aberration [(0.74±0.35) μm and (0.41±0.12) μm] were the highest in monofocal group, followed by bifocal group [(0.61±0.21) μm and (0.22±0.09) μm] and depth of focus extension group [(0.46±0.13) μm and (0.06±0.09) μm] (all P<0.05). Conclusions: IOL implantation with depth of focus extension can enhance visual range, night vision and contrast sensitivity, and thus effectively improve postoperative visual quality and function in cataract patients. The bifocal IOL can better improve the patient's UCNVA and BCNVA, resulting in high satisfaction with visual quality.

[Comparison of aspirin treatment strategies for primary prevention of cardiovascular diseases: A decision-analytic Markov modelling study]

OBJECTIVE

To compare the expected population impact of benefit and risk of aspirin treatment strategies for the primary prevention of cardiovascular diseases recommended by different guidelines in the Chinese Electronic Health Records Research in Yinzhou (CHERRY) study.

METHODS

A decision-analytic Markov model was used to simulate and compare different strategies of aspirin treatment, including: Strategy ①: Aspirin treatment for Chinese adults aged 40-69 years with a high 10-year cardiovascular risk, recommended by the 2020 Chinese Guideline on the Primary Prevention of Cardiovascular Diseases; Strategy ②: Aspirin treatment for Chinese adults aged 40-59 years with a high 10-year cardiovascular risk, recommended by the 2022 United States Preventive Services Task Force Recommendation Statement on Aspirin Use to Prevent Cardiovascular Disease; Strategy ③: Aspirin treatment for Chinese adults aged 40-69 years with a high 10-year cardiovascular risk and blood pressure well-controlled (< 150/90 mmHg), recommended by the 2019 Guideline on the Assessment and Management of Cardio-vascular Risk in China. The high 10-year cardiovascular risk was defined as the 10-year predicted risk over 10% based on the 2019 World Health Organization non-laboratory model. The Markov model simulated different strategies for ten years (cycles) with parameters mainly from the CHERRY study or published literature. Quality-adjusted life year (QALY) and the number needed to treat (NNT) for each ischemic event (including myocardial infarction and ischemic stroke) were calculated to assess the effectiveness of the different strategies. The number needed to harm (NNH) for each bleeding event (including hemorrhagic stroke and gastrointestinal bleeding) was calculated to assess the safety. The NNT for each net benefit (i.e., the difference of the number of ischemic events could be prevented and the number of bleeding events would be added) was also calculated. One-way sensitivity analysis on the uncertainty of the incidence rate of cardiovascular diseases and probabilistic sensitivity analysis on the uncertainty of hazard ratios of interventions were conducted.

RESULTS

A total of 212 153 Chinese adults, were included in this study. The number of people who were recommended for aspirin treatment Strategies ①-③ was 34 235, 2 813, and 25 111, respectively. The Strategy ③ could gain the most QALY of 403 [95% uncertainty interval (UI): 222-511] years. Compared with Strategy ①, Strategy ③ had similar efficiency but better safety, with the extra NNT of 4 (95%UI: 3-4) and NNH of 39 (95%UI: 19-132). The NNT per net benefit was 131 (95%UI: 102-239) for Strategy ①, 256 (95%UI: 181-737) for Strategy ②, and 132 (95%UI: 104-232) for Strategy ③, making Strategy ③ the most favorable option with a better QALY and safety, along with similar efficiency in terms of net benefit. The results were consistent in the sensitivity analyses.

CONCLUSION

The aspirin treatment strategies recommended by the updated guidelines on the primary prevention of cardiovascular diseases showed a net benefit for high-risk Chinese adults from developed areas. However, to balance effectiveness and safety, aspirin is suggested to be used for primary prevention of cardiovascular diseases with consideration for blood pressure control, resulting in better intervention efficiency.

[Immune function and research progress of pentraxin 3 in pulmonary infectious diseases]

Pentraxins3 (PTX3) is an acute-phase protein of the pentraxin family that is synthetized and stored in a variety of cells. As an important mediator of innate immunity, PTX3 is rapidly released during microbial invasion and inflammatory response. It promotes the recognition of pathogens by myeloid cells through regulating complement activation. Recent studies have indicated that PTX3 concentrations in peripheral blood or tissues increase rapidly after infection, and the increased level is associated with the severity of the disease. Thus, PTX3 appears to be a vital clinical biomarker in the diagnosis and prognosis of pulmonary infectious diseases.

[Therapeutic efficacy of hematopoietic stem cell transplantation for Wiskott-Aldrich syndrome in 60 children]

Objective: To evaluate the therapeutic efficacy of hematopoietic stem cell transplantation (HSCT) for Wiskott-Aldrich syndrome (WAS), and to analyze the factors related to the outcomes. Methods: The clinical data of 60 children with WAS received HSCT in Shanghai Children's Medical Center from January 2006 to December 2020 were retrospectively analyzed. All cases were treated with a myeloablative conditioning regimen with busulfan and cyclophosphamide, and a graft-versus-host disease (GVHD) prevention regimen based on cyclosporine and methotrexate. Implantation, GVHD, transplant-related complications, immune reconstitution and survival rate were observed. Survival analysis was performed by Kaplan-Meier method, and Log-Rank method was used for univariate comparison. Results: The 60 male patients had main clinical features as infection and bleeding. The age at diagnosis was 0.4 (0.3, 0.8) years, and the age at transplantation was 1.1 (0.6, 2.1) years. There were 20 cases of human leukocyte antigen matched transplantation and 40 mismatched transplantation; 35 patients received peripheral blood HSCT, and 25 cord blood HSCT. All cases were fully implanted. The incidence of acute GVHD (aGVHD) was 48% (29/60) and only 2 (7%) developed aGVHD of grade Ⅲ; the incidence of chronic GVHD (cGVHD) was 23% (13/56), and all cases were limited. The incidence of CMV and EBV infection was 35% (21/60) and 33% (20/60) respectively; and 7 patients developed CMV retinitis. The incidence of sinus obstruction syndrome was 8% (5/60), of whom 2 patients died. There were 7 cases (12%) of autoimmune hemocytopenia after transplantation. Natural killer cells were the earliest to recover after transplantation, and B cells and CD4⁺T cells returned to normal at about 180 days post HSCT. The 5-year overall survival rate (OS) of this group was 93% (95%CI 86%-99%), and the event free survial rate (EFS) was 87% (95%CI 78%-95%). EFS of non-CMV reactivation group is higher than that of CMV reactivation group (95% (37/39) vs.71% (15/21), χ²=5.22, P=0.022). Conclusions: The therapeutic efficacy of HSCT for WAS is satisfying, and the early application of HSCT in typical cases can achieve better outcome. CMV infection is the main factor affecting disease-free survival rate, which can be improved by strengthening the management of complications.

[Application of discrete event simulation model in analysis on cost-effectiveness of epidemiology screening]

Discrete event simulation (DES) model is based on individual data, by which discrete events over time are simulated to reflect disease progression. The effects of individual characteristics on disease progression could be considered in the DES model. Moreover, unlike state-transition models, DES model without setting of fixed cycle can contribute to more accurate estimation of event time, especially in the evaluation of the long-term effectiveness of screening strategies for complex diseases in which time dimension needs to be considered. This article introduces the general principles, construction steps, analytic methods and other relevant issues of the DES model. Based on a research case of estimating the cost-effectiveness of screening for abdominal aortic aneurysms in women aged 65 years and above in the United Kingdom, key points in applications of the DES model in analysis on effectiveness of complex disease screening are discussed in detail, including model construction and analysis and interpretation of the results. DES model can predict occurring time of discrete events accurately by establishing the distribution function of their occurring time and is increasingly used to evaluate the screening strategies for complex diseases in which time dimension needs to be considered. In the construction of DES model, it is necessary to pay close attention to the clear presentation of model structure and simulation process and follow the relevant reporting specification to conduct cost-effectiveness analysis to ensure the transparency and repeatability of the research.

[Effect of postoperative adjuvant chemotherapy on prognosis of patients with intrahepatic cholangiocarcinoma:a multicenter retrospective study]

Objectives: To examine the influence of adjuvant chemotherapy after radical resection on the survival of patients with intrahepatic cholangiocarcinoma(ICC) and to identify patients who may benefit from it. Methods: The clinical and pathological data of 654 patients with ICC diagnosed by postoperative pathology from December 2011 to December 2017 at 13 hospitals in China were collected retrospectively. According to the inclusion and exclusion criteria,455 patients were included in this study,including 69 patients (15.2%) who received adjuvant chemotherapy and 386 patients (84.8%) who did not receive adjuvant chemotherapy. There were 278 males and 177 females,with age of 59 (16) years (M(IQR))(range:23 to 88 years). Propensity score matching (PSM) method was used to balance the difference between adjuvant chemotherapy group and non-adjuvant chemotherapy group. Kaplan-Meier method was used to plot the survival curve,the Log-rank test was used to compare the difference of overall survival(OS) and recurrence free survival(RFS)between the two groups. Univariate analysis was used to determine prognostic factors for OS. Multivariate Cox proportional hazards models were then performed for prognostic factors with P<0.10 to identify potential independent risk factors. The study population were stratified by included study variables and the AJCC staging system,and a subgroup analysis was performed using the Kaplan-Meier method to explore the potential benefit subgroup population of adjuvant chemotherapy. Results: After 1∶1 PSM matching,69 patients were obtained in each group. There was no significant difference in baseline data between the two groups (all P>0.05). After PSM,Cox multivariate analysis showed that lymph node metastasis (HR=3.06,95%CI:1.52 to 6.16,P=0.039),width of resection margin (HR=0.56,95%CI:0.32 to 0.99,P=0.044) and adjuvant chemotherapy (HR=0.51,95%CI:0.29 to 0.91,P=0.022) were independent prognostic factors for OS. Kaplan-Meier analysis showed that the median OS time of adjuvant chemotherapy group was significantly longer than that of non-adjuvant chemotherapy group (P<0.05). There was no significant difference in RFS time between the adjuvant chemotherapy group and the non-adjuvant chemotherapy group (P>0.05). Subgroup analysis showed that,the OS of female patients,without HBV infection,carcinoembryonic antigen<9.6 μg/L,CA19-9≥200 U/ml,intraoperative bleeding<400 ml,tumor diameter>5 cm,microvascular invasion negative,without lymph node metastasis,and AJCC stage Ⅲ patients could benefit from adjuvant chemotherapy (all P<0.05). Conclusion: Adjuvant chemotherapy can prolong the OS of patients with ICC after radical resection,and patients with tumor diameter>5 cm,without lymph node metastasis,AJCC stage Ⅲ,and microvascular invasion negative are more likely to benefit from adjuvant chemotherapy.

[Relationship between expression of NLRP3 inflammasome and improvement of macular structure in patients with wet age-related macular degeneration after anti-vascular endothelial growth factor therapy]

Objective: To explore the relationship between expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome and improvement of macular structure in patients with wet age-related macular degeneration (wAMD) after anti-vascular endothelial growth factor (VEGF) therapy. Methods: A before-after study was carried out. A total of 110 patients (110 eyes) with wAMD who were admitted to Department of Ophthalmology, People's Hospital Affiliated to Shandong First Medical University between August 2019 and December 2021 were enrolled, and all patients were given vitreous injection of anti-VEGF drug (ranibizumab or bevacizumab). The aqueous humor was collected to detect mRNA levels of NLRP3, cysteinyl aspartate specific protease-1 (Caspase-1), apoptosis-associated speck-like protein (ASC) and interleukin (IL) 1β by fluorescence quantitative PCR. The levels of IL-1β, IL-18, tumor necrosis factor α (TNF-α) and VEGF in aqueous humor were detected by enzyme-linked immunosorbent assay (ELISA). The correlation between the above indexes and central macular thickness (CMT) in wAMD patients was analyzed by multivariate linear regression analysis. Results: In the 110 wAMD patients, there were 68 males and 42 females, with a mean age of (68.7±7.6) years. Compared with those before treatment, mRNA levels of NLRP3 (1.65±0.27, 1.34±0.19 vs 1.97±0.23, both P<0.017), Caspase-1 (1.47±0.15, 1.29±0.17 vs 1.53±0.18, both P<0.017), ASC (1.33±0.14, 1.21±0.18 vs 1.47±0.12, both P<0.017) and IL-1β (1.78±0.21, 1.46±0.17 vs 2.21±0.24, both P<0.017), and levels of IL-1β [(26.9±5.7), (20.3±4.6) vs (33.6±8.3) ng/L, both P<0.017], IL-18 [(32.7±7.6), (23.3±6.9) vs (46.4±9.4) ng/L, both P<0.017], TNF-α [(39.4±6.6), (21.7±6.3) vs (52.9±9.1) ng/L, both P<0.017] and VEGF [(35.7±10.2), (23.4±6.7) vs (65.4±19.3) ng/L, both P<0.017] were decreased after the first and second injection. Moreover, the above-mentioned indexes after second injection were lower than those after the first injection (all P<0.017). The results of multivariate linear regression analysis showed that NLRP3 mRNA (the first injection: β=53.750, P<0.001; the second injection: β=94.648, P<0.001), IL-1β (the first injection: β=1.356, P=0.021; the second injection: β=2.008, P=0.003), IL-18 (the first injection: β=1.984, P<0.001; the second injection: β=1.251, P=0.003) and VEGF (the first injection: β=1.875, P<0.001; the second injection: β=2.119, P<0.001) had linear relationships with CMT. Conclusion: The decrease of NLRP3 inflammasome and its products in aqueous humor may be related to the improvement of macular structure in wAMD patients after anti-VEGF therapy.

[Estimation of molecular clock of Mycobacterium tuberculosis based on whole genome sequencing data]

Objective: To analyze the genomic mutation of Mycobacterium tuberculosis (M. tuberculosis) isolated in endogenous activation period and estimate the molecular clock based on the whole genome sequencing data. Methods: Literatures of the whole genome research of endogenous reactivated tuberculosis were retrieved, and the corresponding whole genome sequencing data were downloaded. We extracted the single nucleotide polymorphisms (SNPs) and strain isolation time of initial treatment and relapse of tuberculosis cases, explored the relationship between the different SNPs and interval between initial treatment and relapse by Poisson regression model, calculated the M. tuberculosis molecular clock, and estimated the mutation rate. Results: When the generation time of M. tuberculosis was 18 hours, the mutation rate in 0-2 years, i.e. short-term endogenous activation, was 6.47×10^-10 (95%CI: 5.59×10^-10-7.44×10^-10), which was significantly higher than that in 2-14 years in long term endogenous activation (3.27×10^-10, 95%CI: 2.88×10^-10-3.69×10^-10). The mutation rates of 0-, 1-, 2-, 3-, 5- and 7-14 years were 7.10×10^-10, 6.06×10^-10, 4.24×10^-10, 5.34×10^-10, 2.59×10^-10 and 1.26×10^-10 respectively. Conclusions: In the period of endogenous reactivation, the mutation rate of M. tuberculosis decreases with the interval time between initial treatment and relapse, which verifies the clinically observed phenomenon that the relapse often occurs within two years after the initial treatment of tuberculosis.

[Study of transmissibility of 2019-nCoV Omicron variant in Beijing]

Objective: To evaluate the transmissibility of 2019-nCoV Omicron variant under the current prevention and control strategy in Beijing, and provide evidence for the prevention and control of COVID-19. Methods: The information of 78 Omicron variant infection cases involved in clear transmission chains in Beijing during 7-25 March, 2022 were collected, the incubation period and serial interval of the disease were fitted by using Gamma and Weibull distribution. Markov Chain Monte Carlo approach was used to estimate the time-varying reproduction number (R_t). Results: The median of the incubation period (Q₁, Q₃) of Omicron variant infection was 4.0 (3.0, 6.0) days, and the serial interval was 3.0 (2.0, 5.0) days. The median of the serial interval (Q₁, Q₃) was 2.0 (1.0, 4.0) days in unvaccinated cases and 4.0 (2.0, 6.0) days in vaccinated cases (Z=-2.12, P=0.034), and 2.0 (1.5, 3.0) days in children and 4.0 (2.0, 6.0) days in adults, respectively (Z=-2.02,P=0.044), the differences were significant. The mean of R_t was estimated to be 4.98 (95%CI: 2.22-9.04) for Omicron variant in this epidemic. Conclusion: Omicron variant has stronger transmissibility compared with Delta variant. It is necessary to strengthen the routine prevention and control COVID-19, promote the vaccination and pay close attention to susceptible population, such as children.

Impacts of international food and feed trade on nitrogen balances and nitrogen use efficiencies of food systems

International trade of agricultural products has greatly increased over time, but its impacts on sustainable development are debated. It may contribute to food security in importing countries, increases the dependency between countries, and has been implicated in displacement of environmental pollution and resource depletion. There is also discussion about the relationships between trade and nitrogen (N) balances and N use efficiencies (NUE). We explored relationships between changes in the trade of food and feed and in N balances and NUE of the food supply systems through simulation modeling and an analysis of empirical data of 115 countries (representing 91% of global population) for the period 1961-2011. In the empirical analysis, 64 main importing countries and 14 main exporting countries, were distinguished. Importing countries had on average a higher population density than exporting countries but rather similar protein intake and GDP per capita. The empirical analysis indicate that main importing countries had on average higher N fertilizer inputs to their food supply systems, and also higher N surpluses and higher NUE than main exporting countries. The overall mean NUE of the food supply system of main importing countries decreased with increasing import, but the relationships between import and NUE were diverse when these countries were grouped according to population density and GDP per capita. We compared N balances and partial N balances, and three methodologies commonly used for estimating NUE. We observed that NUE2 provides an unbiased estimate for both importing and exporting countries. Our study contributes to the understanding of the diverse relationships between international trade, N balances and NUE of food systems.

[Progress in research of chronic obstructive pulmonary disease and risk factors]

Chronic obstructive pulmonary disease (COPD) is a common, preventable and treatable chronic airway disease characterized by persistent airflow restriction and associated respiratory symptoms. COPD is the main cause of morbidity and mortality of chronic diseases and one of the top three causes of death in the world. The prevalence of COPD among provinces in China are at a high levels for years. The prevalence of COPD varies from country to country, region to region, and population to population, and the incidence and development of COPD are influenced by multi risk factors, including individual genetic factors, age, sex, body mass index, abdominal obesity and physical activity and environment factors, such as smoking, indoor and outdoor air pollution, and occupational exposure.

[Effectiveness of statin treatment strategies for primary prevention of cardiovascular diseases in a community-based Chinese population: A decision-analytic Markov model]

OBJECTIVE

To evaluate the effectiveness of statin treatment strategies based on risk assessment for the primary prevention of cardiovascular diseases by the Western guidelines in a community-based Chinese population from economically developed areas using data from the Chinese electronic health records research in Yinzhou (CHERRY) study.

METHODS

A Markov model was used to evaluate the effectiveness of the following statin treatment strategies, including: (1) usual care without cardiovascular risk assessment(Strategy 0); (2) using the World Health Organization (WHO) non-laboratory-based risk charts with statin treatment for high-risk group (risk ≥ 20%) (Strategy 1); (3) using the WHO laboratory-based risk charts with statin treatment for high-risk group (risk ≥ 20%) (Strategy 2); and (4) using the Prediction for Atherosclerotic cardiovascular disease Risk in China (China-PAR) model with statin treatment for high-risk group (risk ≥ 10%, Strategy 3). According to the guidelines, adults in the medium-risk group received lifestyle intervention, and adults in the high-risk group received life-style intervention and statin treatment under these strategies. The Markov model simulated different strategies for ten years (cycles) using parameters from the CHERRY study, published data, meta-analyses and systematic reviews for Chinese. The number of cardiovascular events or deaths, as well as the number need to treat (NNT) with statin per cardiovascular event or death prevented, were calculated to compare the effectiveness of different strategies. One-way sensitivity analysis on the uncertainty of incidence rate of cardiovascular diseases, and probabilistic sensitivity analysis on the uncertainty of hazard ratios of interventions were conducted.

RESULTS

Totally 225 811 Chinese adults aged 40-79 years without cardiovascular diseases at baseline were enrolled. In contrast to the usual care without risk assessment-based statin treatment strategy, Strategy 1 using the WHO non-laboratory-based risk charts could prevent 3 482 [95% uncertainty interval (UI): 2 110-4 661] cardiovascular events, Strategy 2 using the WHO laboratory-based risk charts could prevent 3 685 (95%UI: 2 255-4 912) events, and Strategy 3 using the China-PAR model could prevent 3 895 (95%UI: 2 396-5 181) events. NNTs with statin per cardiovascular event prevented were 22 (95%UI: 14-54), 21 (95%UI: 14-52), and 27 (95%UI: 17-67), respectively. Strategy 3 could prevent more cardiovascular events, while Strategies 1 and 2 required fewer numbers need to treat with statin per cardiovascular event prevented. The results were consistent in the sensitivity analyses.

CONCLUSION

The statin treatment strategies based on risk assessment for the primary prevention of cardiovascular diseases recommended by the Western guidelines could achieve substantive health benefits in adults from developed areas of China. Using the China-PAR model for cardiovascular risk assessment could prevent more cardiovascular diseases while using the WHO risk charts seems more efficient.

[Applications of the NDR and DIAL models for risk prediction on cardiovascular disease in patients with type 2 diabetes in Ningbo]

Objective: To validate the performance of cardiovascular risk prediction models based on the Sweden National Diabetes Register (NDR) and Diabetes Lifetime-perspective prediction (DIAL) model for assessing risks of 5-year and 10-year cardiovascular disease (CVD) among Chinese patients with type 2 diabetes. Methods: Based on the Chinese Electronic Health Records Research in Yinzhou study, 83 503 patients with type 2 diabetes aged 30-75 years without a history of CVD at baseline were included from January 1, 2010 to December 31, 2020. Recalibrated NDR model was used to estimate 5-year risk, while the recalibrated DIAL model was used to predict 5-year and 10-year risks. The competing events adjusted Kaplan-Meier analysis was used to obtain the observed cardiovascular events. Discrimination C statistics evaluated model accuracy, calibration χ² value, and calibration plots. Results: Through a median follow-up of 7.0 years, 7 326 cardiovascular events, and 2 937 non-vascular deaths were identified among a total of 83 503 subjects. The recalibrated NDR model overestimated 5-year risk by 39.4% in men and 8.6% in women, whereas the overestimation for the recalibrated DIAL model was 14.6% in men and 50.1% in women. The DIAL model had a better discriminative ability (C-statistic=0.681, 95%CI: 0.672-0.690) than NDR model (C-statistic=0.667, 95%CI: 0.657-0.677) in 5-year risk prediction for men, and the models had a similar ability for women (C-statistic=0.699, 95%CI: 0.690-0.708 for NDR and C-statistic=0.698, 95%CI: 0.689-0.706 for DIAL). The prediction accuracy of the DIAL model was improved in the 10-year risk, with the underestimation being 1.6% for men and the overestimation being 12.8% for women. Conclusions: Both recalibrated NDR and DIAL models overestimated 5-year cardiovascular risk in Chinese patients with type 2 diabetes, while the higher overestimation was shown using the DIAL model. However, the improvement was found in predicting 10-year CVD risk using the DIAL model, which suggested the value of lifetime risk prediction and indicated the need for research on the lifetime risk prediction model for cardiovascular risk assessment in Chinese patients with type 2 diabetes.

[Applications of microsimulation model for cost-effectiveness analysis on screening in epidemiology]

Microsimulation model simulates individuals and estimates transition probabilities within the population using individual participant data. This approach could deal with the heterogeneous characteristics among the people or personal history of diseases and may be relevant in addressing cost-effectiveness problems of screening for complex conditions in epidemiology. This paper introduces the general principles, basic steps involved in implementation, analytic methods, and other related issues of the microsimulation model. Based on a practical research case of estimating the cost-effectiveness of microalbuminuria screening for chronic kidney disease in the United States, critical points in applications of the microsimulation model for cost-effectiveness analysis of screening were discussed in detail, including model development, model analysis, and the interpretation of the results. The microsimulation model considers the dynamic nature of complex diseases by estimating a broad range of individual characteristics and increasingly used to provide insights into complex problems that the Markov model does not efficiently address. For better supporting evidence-informed decision-making in public health, future studies should be aware of the accuracy of parameters in the decision-analytic model and the transparency of the models and results, as well as complying with the relevant reporting standards.

[Effects and mechanism of hydrogen peroxide pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells]

Objective: To investigate the effects and mechanism of hydrogen peroxide (HP) pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells (BMSCs). Methods: The experimental research methods were used. BMSCs were isolated and cultured from two 2-week-old male BALB/c mice by the whole bone marrow culture method. The 3rd-7th passages of cells in logarithmic growth phase were used for the experiments after identification. According to the random number table (the same grouping method below), the cells were divided into 0 μmol/L HP group (without HP, the same below), 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. The apoptosis rate was detected by flow cytometry (n=4) after 24 hours of culture. The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, and 100 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively. After 24 hours of culture, the protein expressions of B-lymphoma-2 (Bcl-2) and Bcl-2-related X protein (Bax) were detected by Western blotting, and the Bcl-2/Bax ratio was calculated (n=3). The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 200 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. After 24 hours of culture, the protein expressions of glycogen synthase kinase-3β (GSK-3β) and phosphorylated GSK-3β (p-GSK-3β) were detected by Western blotting (n=3). The cells were divided into 0 μmol/L HP group, 50 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively, and HP pretreatment group with 50 μmol/L HP being added in advance for 12 h and then 300 μmol/L HP being added. After 24 hours of culture, the morphology and growth of cells were observed by inverted fluorescence microscopy (non-fluorescent condition) and immunofluorescence method, the apoptosis rate was detected by flow cytometry, the protein expressions of Bcl-2, Bax, cysteine aspartic acid specific protease-3 (caspase-3), caspase-9, cleavage caspase-3, cleavage caspase-9, GSK-3β, and p-GSK-3β were detected by Western blotting, and the Bcl-2/Bax ratio was calculated, with all the number of samples being 3. Data were statistically analyzed with one-way analysis of variance and Bonferroni test. Results: After 24 hours of culture, compared with that in 0 μmol/L HP group, the apoptosis rate of cells did not change significantly in 25 μmol/L HP group, 50 μmol/L HP group, or 100 μmol/L HP group (P>0.05) but increased significantly in 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group (P<0.01). After 24 hours of culture, compared with that in 0 μmol/L HP group, the Bcl-2/Bax ratio of cells increased significantly in 25 μmol/L HP group and 50 μmol/L HP group (P<0.05 or P<0.01) but decreased significantly in 100 µmol/L HP group (P<0.05). After 24 hours of culture, compared with those in 0 μmol/L HP group, the protein expression of GSK-3β in cells showed no significant change in 25 μmol/L HP group and 50 μmol/L HP group (P>0.05), the protein expressions of p-GSK-3β in cells significantly increased in 25 μmol/L HP group and 50 μmol/L HP group (P<0.01), the protein expressions of GSK-3β and p-GSK-3β in cells in 100 μmol/L HP group showed no significant change (P>0.05), the protein expressions of GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group were significantly increased (P<0.05). but the protein expression of p-GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group was significantly decreased (P<0.05). After 24 hours of culture, the morphology and growth of cells in 0 μmol/L HP group and 50 μmol/L HP group were similar and normal; in contrast, the cells in 300 µmol/L HP group became smaller and round, with the cell protrusions being shorter or disappeared, the nucleus being cavitated, and the cell abscission being increased significantly; the morphology of most cells in HP pretreatment group was normal, with the shedding of cells being less than that in 300 µmol/L HP group, and the morphology of nucleus being normal. After 24 hours of culture, the protein expression of caspase-9 was similar among the four groups (P>0.05). Compared with that in 0 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 50 μmol/L HP group showed no significant changes (P>0.05), the Bcl-2/Bax ratio of cells in 50 μmol/L HP group increased significantly (P<0.05), the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 300 μmol/L HP group were significantly increased (P<0.01), while the Bcl-2/Bax ratio of cells in 300 μmol/L HP group was significantly decreased (P<0.05). Compared with those in 300 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells were significantly decreased in HP pretreatment group (P<0.05 or P<0.01), while the Bcl-2/Bax ratio of cells was significantly increased in HP pretreatment group (P<0.01). After 24 hours of culture, the protein expressions of GSK-3β and p-GSK-3β of cells in 0 μmol/L HP group, 50 μmol/L HP group, 300 μmol/L HP group, and HP pretreatment group were 1.09±0.14, 0.62±0.17, 1.35±0.21, 0.74±0.34, 0.68±0.03, 0.85±0.08, 0.38±0.10, and 0.54±0.09, respectively. Compared with those in 0 μmol/L HP group, the protein expression of p-GSK-3β of cells was significantly increased in 50 μmol/L HP group (P<0.05) but significantly decreased in 300 μmol/L HP group (P<0.01), while the protein expression of GSK-3β of cells was significantly increased in 300 μmol/L HP group (P<0.05). Compared with those in 300 μmol/L HP group, the protein expression of GSK-3β of cells was significantly decreased in HP pretreatment group (P<0.01), while the protein expression of p-GSK-3β of cells was significantly increased in HP pretreatment group (P<0.01). Conclusions: The molarity of 50 μmol/L may be the optimal molarity of HP to pretreat mouse BMSCs, and 50 μmol/L HP pretreatment can antagonize mitochondrial pathway of oxidative stress induced apoptosis by inhibiting the activity of GSK-3β.

[Immunogenicity and influencing factors of hepatitis B vaccination based on different vaccination schedules among chronic kidney disease patients]

Objective: To explore the immunogenicity and influencing factors of hepatitis B vaccination based on different vaccination schedules among chronic kidney disease (CKD) patients. Methods: CKD patients who participated in randomized controlled trials in four hospitals in Shanxi province and completed three doses of 20 µg vaccination (at months 0, 1 and 6) and four doses of 20 µg or 60 µg vaccination (at months 0, 1, 2, and 6) were surveyed from May 2019 to July 2020.According to the ratio of 1∶1∶1, 273 CKD patients were divided into 3 groups randomly. Quantification of the anti-hepatitis B surface antigen-antibody (anti-HBs) in serum samples was performed using chemiluminescent microparticle immunoassay at months 1 and 6 after the entire course of the vaccinations. The positive rate, high-level positive rate, geometric mean concentration (GMC) of anti-HBs, and the influencing factors were analyzed by χ² tests, analysis of variance, unconditional logistic regression analysis. Results: A total of 273 CKD patitents were participants.The positive rates in the CKD patients with four doses of 20 µg vaccination (92.96%,66/71) or 60 µg vaccination (93.15%, 68/73) were higher than that in the CKD patients with three doses of 20 µg vaccination (81.69%, 58/71) at month one after the full course of the vaccinations (P<0.05). The GMCs of anti-HBs showed similar results (2 091.11 mIU/ml and 2 441.50 mIU/ml vs. 1 675.21 mIU/ml) (P<0.05). The positive rate was higher in the CKD patients with four doses of 60 µg vaccination (94.83%,55/58) than in those with three doses of 20 µg vaccination (78.79%,52/66) (P<0.05) at month six after the full course of the vaccinations. And the GMC of anti-HBs in the patients with four doses of 60 µg vaccination (824.28 mIU/ml) was significantly higher than those in the patients with 3 or 4 doses of 20 µg vaccination (639.74 mIU/ml and 755.53 mIU/ml) (P<0.05). After controlling the confounding factors, the positive rate in the CKD patients with four doses of 60 µg vaccination were 3.19 (95%CI: 1.02-9.96) and 5.32 (95%CI: 1.27-22.19) times higher than those in the patients with three doses of 20 µg vaccination at months 1 and 6 after the full course of the vaccinations, respectively. The positive rate in CKD patients without immune suppression or hormone therapy was 3.33 (95%CI: 1.26-8.80) and 4.78 (95%CI: 1.47-15.57) times higher than those in the patients with such therapy, respectively. Conclusions: Four doses of 20 µg or 60 µg hepatitis B vaccination could improve the immunogenicity in patients with CKD. And four doses of 60 µg vaccination might play a positive role in maintaining anti-HBs in this population. The immunogenicity in the CKD patients with immune suppression or hormone therapy was poor.

[The application of artificial intelligence on the classification of benign and malignant breast tumors based on dynamic enhanced MR images]

This retrospective analysis was conducted on clinical obtained DCE-MR images of 198 patients, age from 21 to 79 years(45.5±13.7). The CBAM-ResNet model was developed to perform the classification automatically at the image-level based on deep learning method using the pathological examination as the reference standard,then the classification result of each individual patient was obtained by ensemble learning. The proposed method can have an accuracy of 82.69% for correctly distinguishing between benign and malignant breast tumors at the slice-level based on CBAM-ResNet model and with a sensitivity of 85.67%.. After the voting mechanism is applied, the classification accuracy can reach up to 88.24% at the patient-level with a sensitivity of 87.50%. Our experimental results demonstrated the proposed approach have a high classification accuracy.

[Clinical analysis of 60 children with anaplastic large cell lymphoma in a single center]

Objective: To summarize the clinical features, treatment outcome and prognostic factors of childhood anaplastic large cell lymphoma (ALCL). Methods: Clinical data of 60 newly diagnosed and biopsy-proven ALCL pediatric patients (≤18 years of age) at Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine from January 2010 to December 2018 were collected. All patients were treated with the Chinese Children Cancer Group-B cell-non-Hodgkin Lymphoma 2010 (CCCG-BNHL-2010) regimen. Overall survival (OS), event free survival (EFS) and progression free survival (PFS) rates were calculated by the Kaplan-Meier method. Univariate analysis was performed with Log-Rank test to find factors of poor prognosis. Results: Among 60 ALCL patients included in the current study, 39 were males and 21 females, the age of onset was 7.9 (1.2-16.7) years. Among all cases, 43 (72%) had B syndrome (any of the following: fever, drenching, weight loss). Forty-nine (82%) cases had lactate dehydrogenase (LDH) levels<2 times upper limit of normal (ULN) and 11 (18%) cases had LDH levels 2-<4 times ULN. The distribution of stages was stage Ⅰ,Ⅱ,Ⅲ, and Ⅳ in 2% (1/60), 5% (3/60), 92% (55/60), and 2% (1/60) of patients, respectively. Of 58 cases who had results of anaplastic lymphoma kinase (ALK) immunohistochemical staining, 53 (91%, 53/58) cases were positive. Visceral involvement was observed in 12 patients (20%). The 4-year OS and EFS rates were (88±4)% and (76±6)% for the entire group, respectively. Univariate analysis for gender, B symptoms, LDH level, ALK expression, clinical stage and visceral involvement showed that only LDH level correlated with an inferior OS rate (χ²=6.571, P=0.010) while not correlated with EFS rate. No independent risk factor for disease progression or recurrence was found by Logistic regression. Up to the last follow-up, 44 cases were continuously at complete remission state, and their follow-up time was 50 (13-119) months. Of 13 (23%) cases experienced disease progression or relapse, 3 cases abandoned treatment, 2 cases progressed to death, 8 cases received second line or salvage treatment (6 survived at last follow-up). For post progression or relapse cases, the 2-year OS and PFS rates were (60±16)% and (16±14)%, respectively. The treatment related death occurred in 3 cases (5%) and all of them were due to severe infection during the chemotherapy. Conclusions: The efficacy of CCCG-BNHL-2010 regimen in the treatment of children with ALCL was good. However, the safety needs to be improved as the treatment-related mortality in the present study was slightly higher. Efficient second line or salvage treatment can achieve cure in pediatric patients post progression or recurrence. LDH ≥2 times ULN was associated with worse prognosis.

[Clinical features and perinatal outcomes of 48 cases of pregnancy complicated with placental cystic lesions]

Objective: To investigate the clinical characteristics and perinatal outcomes of pregnancy with placental cystic lesions. Methods: A retrospective study was carried out on 48 pregnant women diagnosed as pregnancy complicated with placental cystic lesions from January 2000 to January 2020 at the Women's Hospital, Zhejiang University School of Medicine. The clinical features, pathological diagnosis and perinatal outcome were analyzed. Results: The age of 48 cases was (30±5) years, and the diagnostic gestational week of ultrasound was (24±8) weeks. Twenty-five cases in which showed a cystic mass at the fetal surface were diagnosed as placental cyst. The live birth rate was 100% (25/25) and the premature birth rate was 20% (5/25). Twenty-three cases showed "honeycomb like" cystic echo. Cystic lesions of 10 cases were located in the uterine cavity connected with the margin of the normal placenta, and finally diagnosed as hydatidiform mole and coexisting fetus (HMCF). Six cases of HMCF terminated pregnancy, and the live birth rate was 4/10, the premature delivery rate was 2/4. Cystic lesions of 13 cases were located in the placenta substance, and finally diagnosed as 4 cases of placental mesenchymal dysplasia (PMD) and 9 cases of focal chorionic edema; the live birth rate was 6/13 and the premature delivery rate was 4/6. The median hCG was lower in focal chorionic edema group [80 kU/L (60-110 kU/L)] than in the groups of HMCF [240 kU/L (180-430 kU/L)] and PMD [360 kU/L (210-700 kU/L)], and the differences were statistically significant (all P<0.01). Conclusions: For pregnancy complicated with placental cystic lesions, prenatal ultrasound should be performed to evaluate the shape, location and blood flow of the lesions. Maternal serological examination and invasive prenatal diagnosis are helpful for prenatal diagnosis and treatment. Due to the difference of perinatal outcomes, maternal and fetal complications, individualized pregnancy management should be carried out.

[Incidence of unintended pregnancy within 2 years after delivery and its influencing factors in China]

Objective: To investigate the present situation of unintended pregnancy within two years postpartum and its influencing factors in China. Methods: Participants who delivered a live birth at 60 hospitals in 15 provinces in the eastern, central and western regions of China during July 2015 to June 2016 were interviewed by using structured questionnaire. Information on occurrence of unintended pregnancy within 2 years after delivery, postpartum contraceptive use, sexual resumption, breastfeeding, and women's socio-demographic characteristics, and so on, were collected. Life-table analysis, cluster log-rank tests and a 2-level Cox regression model were used for data analysis. Results: A total of 18 045 postpartum women were investigated. The cumulative 1- and 2-year unintended pregnancy rates after delivery were 5.3% (95%CI: 4.5%－6.1%) and 13.1% (95%CI: 11.3%－14.8%), respectively. Cox regression model analysis showed that the risk of unintended pregnancy within 2 years postpartum were increased in younger women, ethnic minorities, women with abortion history, and those who had a vaginal delivery with short lactation time and late postpartum contraceptive initiation (all P<0.01). The risk of postpartum unintended pregnancy was not associated with geographic regions and hospitals where women gave a birth (all P>0.05). Conclusions: In China, the risk of unintended pregnancy within 2 years after delivery is relatively high. Service institutions and service providers should improve the quality of postpartum family planning services, promote the use of high effect contraceptive methods, and educate women to use a method at the time of their sexual resumption or even before.

[Immunity persistence of 60 μg high dose hepatitis B vaccine and influencing factors in maintained hemodialysis patients]

Objective: To compare the anti-HBs level in maintained hemodialysis patients one year after receiving 20 μg and 60 μg hepatitis B vaccination at 0, 1 and 6 months, and explore the influence factors for the immunity persistence and their interactions. Methods: Based on a randomized controlled trial of 20 μg and 60 μg hepatitis B vaccine immunization in maintained hemodialysis patients at 0, 1, and 6 months, follow up was conducted for the patients for one year after the completion of the vaccination for the quantitative detection of anti-HBs, and χ² test, t test, unconditional logistic regression and interaction analyses were used for statistical analysis. Results: One year after the vaccination, 125 and 124 patients in the 20 μg and 60 μg groups were tested for anti-HBs, respectively. The positive rate of anti-HBs in the 60 μg group (77.42%, 96/124) was significantly higher than that in the 20 μg group (65.60%, 82/125) (P<0.05). After adjusting for the confounding factors, the positive probability of anti-HBs in the 60 μg group was 1.925 times higher than that in the 20 μg group (95%CI: 1.068-3.468). Patients with hemodialysis duration ≥5 years (OR=0.523, 95%CI: 0.293-0.935) and diabetes mellitus (OR=0.376, 95%CI: 0.173-0.818) had lower positive probability of anti-HBs. Moreover, there were additive and multiplicative interactions between hemodialysis duration ≥5 years and diabetes mellitus. Conclusions: The immunity persistence after one year in 60 μg hepatitis B vaccination group was longer than that in 20 μg hepatitis B vaccination group in maintained hemodialysis patients, vaccine dose, hemodialysis duration and diabetes mellitus were the influencing factors for the immunity persistence, there were additive and multiplicative interactions between hemodialysis duration ≥5 years and diabetes mellitus.

[Genomic characterization of food-borne Listeria monocytogenes isolates from Nanshan district of Shenzhen during 2009-2019]

Objective: The study aims to investigate the characteristic baseline information about genetic lineages, drug-resistance genes, virulence genes and evolutionary relationships of food-borne Listeria monocytogenes (Lm) isolates from Nanshan district of Shenzhen. Methods: The whole genomes of 46 Lm isolates during 2009-2019 were extracted and sequenced (Illumina PE-150, 100×). The CLC Genomics Workbench 12.0 was used to assemble and align Lm genomes, analyze their housekeeping genes, drug-resistance genes and virulence genes, and construct a k-mer phylogenetic tree. Results: After assembly, all genomes satisfied analytical conditions (contigs N50>20 kb). The medians of GC content, gene count and gene size were 38.3%, 5 960 and 2 952 608 bp, respectively. Based on the Lm genomic reference database, the local k-mer phylogenetic tree had 14 clusters of which the genetic distance was wide. The 46 Lm isolates were classified as Lineage 1 (21), Lineage 2 (23) and Lineage 3 (2). The most common ST type of Lineage 1 was ST87, followed by ST3, ST59, ST224 and ST429, whereas the major ST types of Lineage 2 included ST8 and ST9, the rest being ST121, ST155, ST199, ST204 and ST321. However, Lineage 3 only had ST299. The part of Lm strains carried five drug-resistance genes, such as fosX (17), tetM (6), dfrG (4), catB3 (1) and mefA (1). Furthermore, all strains possessed nine virulence genes, including flaA, iap, actA, hly, mpl, prfA, plcA, plcB and inlB. Nevertheless, six isolates and three of them respectively carried the mutant inlA and inlJ, and other two isolates lacked inlC. Conclusion: The food-borne Lm isolates from Nanshan district of Shenzhen presented genetic and evolutionary diversity. Noted that the drug-resistant strains, which also owned abundant virulence genes with specific functions, could lead to serious infections, particularly those isolates from raw poultry and Flammulina velutipes. It was implied that the local region was at risk due to Listeriosis by food. This study offered reference for prevention, control and treatment of Lm infection to the Greater Bay Area.

[Role of interleukin-6 in human umbilical vein endothelial cell to mesenchymal cell transformation]

Objective: To observe the effect of interleukin-6 (IL-6) on the phenotype and function of human umbilical vein endothelial cells (HUVECs) and explore the role of IL-6 in the process of endothelial-to-mesenchymal transition (EndMT). Methods: The experimental research method was used. Fresh umbilical cord discarded after normal maternal delivery was collected. On the second day of the primary cell isolation and cultivation, the cell morphology was observed under inverted phase contrast microscope. HUVECs of the 4th passage were identified by immunofluorescence method, and 2 batches of HUVECs ofthe 3rd to 5th passages were used for the subsequent experiments. The first batch of cells were divided into 6 groups according to the random number table (the same below): blank control group, 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group. The second batch of cells were divided into 4 groups: blank control group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group,and 50 ng/mL IL-6 group; the cells in blank control group was cultured with complete culture medium only, while the cells in the other groups were added with IL-6 of the corresponding final mass concentrations.Cells from the 1st batch were cultured for 72 hours after grouping, the morphology of HUVECS in the 6 groups was observed under inverted phase contrast microscope. At 72 h after grouping culture, the positive expressions of coagulation factor Ⅷ and α vascular smooth muscle actin (α-SMA) in HUVECs in the 6 groups were detected by immunofluorescence method, and the ratio of the number of double positive cells to the number of coagulation factor Ⅷ positive cells (the ratio of double positive cells for short) was calculated, with 6 samples per group; mRNA expression levels of vascular endothelial cadherin and α-SMA of HUVECs in 6 groups were detected by reverse transcription-polymerase chain reaction, with 3 samples per group.Cells from the 2nd batch were cultured 72 hours after grouping, the protein expression levels of vascular endothelial cadherin, α-SMA, and type Ⅰ collagen in the 4 groups were detected by Western blotting, with 3 samples per group. Data were statistically analyzed with one-way analysis of variance and Bonferroni correction. Results: On the 2nd day after isolation and cultivation, the primary cells were in short spindle shape or polygon, cells of the 4th passage were identified as HUVECs by immunofluorescence method. At 72 hours of culture after grouping, the cells from the 1st batch in the 6 groups changed to long spindle shape morphologically along with the increase of IL-6 concentration, the intercellular connections decreased or disappeared with the gap between cells becoming larger. At 72 h after grouping culture, compared with that inblank control group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 5 ng/mL IL-6 group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the ratio of double positive cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly increased (P<0.01); the ratio of double positive cells in 100 ng/mL IL-6 group was significantly increased compared with those in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly decreased (P<0.01 or P<0.05); compared with that in 5 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 10 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of α-SMA of cells in 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6, group, and 100 ng/mL IL-6 group were significantly increased (P<0.05 or P<0.01). Cells from the 2nd batch were cultured for 72 hours after grouping. Compared with 1.391±0.026 in blank control group, the protein expressions of vascular endothelial cadherin of cells in 10 ng/mL IL-6 group (1.185±0.063), in 25 ng/mL IL-6 group (0.717±0.078), and in 50 ng/mL IL-6 group (0.239±0.064) were significantly decreased (P<0.05); compared with that in 10 ng/mL IL-6 group, the protein expressions of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the protein expression of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group was significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expression levels of α-SMA of cells in 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, and 50 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the protein expression levels of α-SMA of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expressions of type Ⅰ collagen of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.05). Conclusions: After IL-6 treatment, the phenotype and function of HUVECS showed the characteristics of mesenchymal cells in a concentration-dependent manner. The inflammatory factor can promote the process of EndMT, and become one of the important factors regulating the mechanism of tissue fibrosis.

Robot-assisted versus laparoscopic minor hepatectomy: A systematic review and meta-analysis

BACKGROUND

Robot-assisted and laparoscopic surgery are the most minimally invasive surgical approaches for the removal of liver lesions. Minor hepatectomy is a common surgical procedure. In this study, we evaluated the advantages and disadvantages of robot-assisted vs laparoscopic minor hepatectomy (LMH).

METHODS

A systematic literature search was performed in PubMed, Embase, and the Cochrane Library to identify comparative studies on robot-assisted vs. laparoscopicminor hepatectomy up to February, 2020. The odds ratios (OR) and mean differences with 95% confidence intervals were calculated using the fixed-effects model or random-effects model.

RESULTS

A total of 12 studies involving 751 patients were included in the meta-analysis. Among them, 297 patients were in the robot-assisted minor hepatectomy (RMH) group and 454 patients were in the LMH group. There were no significant differences in intraoperative blood loss (P = .43), transfusion rates (P = .14), length of hospital stay (P > .64), conversion rate (P = .62), R0 resection rate (P = .56), complications (P = .92), or mortaliy (P = .37) between the 2 groups. However, the RMH group was associated with a longer operative time (P = .0003), and higher cost (P < .00001) compared to the LMH group. No significant differences in overall survival or disease free survival between the 2 groups were observed. In the subgroup analysis of left lateral sectionectomies, RMH was still associated with a longer operative time, but no other differences in clinical outcomes were observed.

CONCLUSIONS

Although RMH is associated with longer operation times and higher costs, it exhibits the same safety and effectiveness as LMH. Prospective randomized controlled clinical trials should now be considered to obtain better evidence for clinical consensus.

Sources, variability and parameterizations of intra-city factors obtained from dispersion-normalized multi-time resolution factor analyses of PM2.5 in an urban environment

Ambient fine particulate matter (PM_2.5) data of similar continuously monitored species at two air monitoring sites with different characteristics within the City of Toronto were used to gauge the intra-city variations in the PM composition over a largely concurrent period spanning two years. One location was <8 m from the side of a major highway while the other was an urban background location. For the first time, multi-time resolution factor analysis was applied to dispersion-normalized concentrations to identify and quantify source contributions while reducing the influence of local meteorology. These factors were particulate sulphate (pSO4), particulate nitrate (pNO3), secondary organic aerosols (SOA), crustal matter (CrM) that were common to both sites, a hydrocarbon-like organic matter (HOM) exclusive to the urban background site, three black carbon related factors (BC, BC-HOM at the highway site, and a brown carbon rich factor (BC-BrC) at the urban background site), biomass burning organic matter (BBOM) and brake dust (BD) factors exclusive to the highway site. The PM_2.5 composition was different between these two locations, over only a 10 km distance. The sum of SOA, pSO4 and pNO3 at the urban background site averaged 57% of the PM_2.5 mass while the same species represented 43% of the average PM_2.5 mass at the highway site. Local or site-specific factors may be of greater interest for control policy design. Thus, regression analyses with potential explanatory, site-specific variables were performed for results from the highway site. Three model approaches were explored: multiple linear regression (MLR), regression with a generalized reduced gradient (GRG) algorithm, and a generalized additive model (GAM). GAM gave the largest fraction of variance for the locally-found factors at the highway site. Heavy-duty vehicles were most important for explaining the black carbon (BC and BC-HOM) factors. Light-duty vehicles were dominant for the brake dust (BD) factor. The auxiliary modelling for the local factors showed that the traffic-related factors likely originated along the main roadways at their respective sites while the more regional factors, - pSO4, pNO3, SOA, - had sources that were both regional and local in origin and with contributions that varied seasonally. These results will be useful in understanding ambient particulate matter sources on a city scale that will support air quality management planning.

Improved light extraction efficiency of AlGaN deep-ultraviolet light emitting diodes combining Ag-nanodots/Al reflective electrode with highly transparent p-type layer

Enhancement of light extraction efficiency (LEE) of AlGaN-based deep-ultraviolet (DUV) light emitting diodes (LEDs) has been attempted by adopting Ag-nanodots/Al reflective electrodes on a highly transparent complex p-type layer. By thinning the p-GaN to several nm, highly DUV transparent p-type layer is achieved, making it meaningful for the application of reflective electrodes composed of Ag-nanodots and Al film to allow most light emitted upward to be reflected back to the sapphire side. By this approach, the maximum light output power and external quantum efficiency of the DUV-LEDs with optimized Ag nanodots/Al electrodes are severally increased by 52% and 58%, respectively, compared to those with traditional Ni/Au electrodes when the current is below 200 mA.

[Study on transmission dynamic of 15 clusters of COVID-2019 cases in Ningbo]

Objective: To describe the basic characteristics of clusters of coronavirus diseases 2019 (COVID-19) cases in Ningbo, Zhejiang province, and evaluate the generation time (Tg) and basic reproduction number (R(0)) of COVID-19. Methods: The basic information and onset times of the clusters of COVID-19 cases in Ningbo were investigated, the inter-generational interval of the cases were fitted by using gamma distribution, and the R(0) was calculated based on the SEIR model. Results: In the 15 clusters of COVID-19 cases, a total of 52 confirmed cases, 5 cases of nucleic acid-positive asymptomatic cases. The cases occurred from January 23 to February 4, the cases were mainly women. The incubation period was (6.11±3.38) days, and the median was 5 days. The Tg was (6.93±3.70) days. There were no significant differences in Tg between age group<60 years and age group 60 years and above, and between men and women (P=0.551). According to the Tg calculated in this paper, the R(0) of COVID-19 in Ningbo was 3.06 (95%CI: 2.64- 3.51); according to the reported case transmission interval of 7.5 days in the literature, the R(0) was 3.32 (95%CI: 2.51-9.38). Conclusion: There is no age and gender specific differences in the Tg of clusters of COVID-19 cases in Ningbo, and COVID-19 has high infectivity and spreading power in early phase.

[Analysis of Influencing Factors of Single Camera Photogrammetry in Forensic Three-Dimensional Reconstruction]

Abstract

Objective To evaluate the influence of factors such as the selection of equipment, focal length and the selection of reconstruction quality in the reconstruction software on the reconstruction results of single camera photogrammetry and provide reference for the forensic application of single camera photogrammetry. Methods The 19 skulls were measured by traditional measurement method and single camera photogrammetry. The differences between the two measurement methods and within the group with same equipment but different focal length were analyzed. One skull and one corpse were selected as the research objects. According to the reconstruction quality selection conditions in the photogrammetric software, the experimental group was divided into five grades. The model reconstructed by optical scanner was defined as reference model, while the model reconstructed by single camera photogrammetry was defined as test model. The test model was aligned with the reference model, 3D deviation analysis was carried out and the mean error and root mean square （RMS） values were calculated. Results The differences between EOS 7D zoom group and traditional measurement, and within the group with same equipment had statistical significance （P<0.05）. The mean error value and minimum RMS value of the skull reconstructed by single camera photogrammetry and the three-dimensional model of the corpse existed in the medium quality group, and the trend was basically the same. Conclusion The equipment and focal length has no obvious influence on the results of single camera photogrammetry. Lower reconstruction quality can easily cause distortion, while higher reconstruction quality can easily generate noise, so medium quality is preferred.

[Clinical characteristics and survival analysis of 15 cases of HIV-negative plasmablastic lymphoma]

目的

分析HIV阴性的浆母细胞淋巴瘤（PBL）患者的临床病理特征及转归。

方法

回顾性分析海军军医大学附属长海医院2013年1月至2019年8月诊断及治疗的15例HIV阴性PBL患者的临床病理资料及随访结果。

结果

15例HIV阴性PBL患者中男8例，女7例，中位年龄59（17~69）岁，均无明确的免疫抑制状态。所有患者均出现结外受累，Ann Arbor-Cotswolds分期Ⅰ、Ⅱ、Ⅲ、Ⅳ期分别为1例（6.7%）、2例（13.3%）、3例（20.0%）、9例（60.0%）。病理形态表现为类似免疫母细胞的大肿瘤细胞弥漫性增生，免疫组化示肿瘤细胞主要表达浆细胞标志CD38、CD138、Mum-1，B细胞标志CD20、CD10、PAX-5、BCL-6少见，Ki-67中位数为80%（70%~90%）。3例患者行EBER原位杂交检测，1例阳性。15例患者均接受化疗，80%（12/15）联合硼替佐米作为一线治疗。最佳疗效6例完全缓解（其中2例分别于治疗后4.9和26.1个月疾病进展），2例部分缓解（分别于治疗后3.0和6.8个月疾病进展），4例疾病进展，3例无法评估。中位随访时间30.3（4.8~61.1）个月，11例患者中位无进展生存（PFS）期6.8（95%CI 2.5~11.1）个月，预计3年PFS率为21.2%（95%CI 1.4%~56.8%）。所有患者中位总生存（OS）期为17.9（95%CI 5.6~30.2）个月，预计3年OS率为38.5%（95%CI 12.0%~65.0%）。

结论

HIV阴性PBL侵袭性强，结外受累常见，多数患者诊断时分期较晚。通过以硼替佐米为基础的强化疗方案序贯自体造血干细胞移植可望获得长期生存。

[Association between the morphology of the implanted atrial septal defect occluding umbrella and postoperative headache]

Objective: To explore whether the atrial septal defect(ASD) size, the type of occlusion umbrella selected, and the morphological changes after release of occlusion umbrella affect the headache symptoms of ASD patients after operation. Methods: A total of 567 ASD ptients, who underwent successful implantion with a single occlude from January 2014 to December 2017 in General Hospital of Northern Theater Command were enrolled. The patients were divided into symptomatic group and asymptomatic group according to the presence or absence of headache symptoms after occlusion. X-ray catheter calibration method was used to measure the diameter(d), thickness（L）, maximum diameter of the left umbrella surface after release(D2) and the value of i (i = D2/L). Risk factors related to headache were analyzed by multivariate logistic regression analysis. linear regression analysis was used to detect the relationship between the type of occluder umbrella and ASD diameter in asymptomatic group. Results: A total of 567 patients with one occluder umbrella were included, and 148(26.1%) cases were male. The age was (34.4±19.4) years old. The follow-up time was (12.7±2.8) months. There were 51 cases in the symptomatic group and 516 cases in the asymptomatic group. In 29 patients who were treated by extending the course or increasing the dose of aspirin, the symptoms disappeared or improved. There was no significant difference in the maximum ASD diameter (TTE measured) and the size of occluder between the symptomatic group and asymptomatic group(both P>0.05). The value of d ((19.80±6.67)mm vs.(17.40±7.28) mm, P=0.041) D2 ((43.29±7.41）mm vs. (39.20±9.59)mm， P=0.013)and L((13.06±3.72)mm vs. (10.19±2.90) mm，P=0.025) of the symptomatic group were all higher than that of the asymptomatic group，while the i value was smaller((3.54±0.88）vs.(3.99±0.93)，P=0.010）. The results of multivariate logistic regression analysis showed that the value of L(OR=1.286，95%CI 1.176-1.406, P=0.002) and the value of i(OR=0.916，95%CI 0.867-0.968, P<0.001) were independent factors of headache symptoms in patients after ASD occlusion, while the value of d and the value of D2 were not independent factors (both P>0.05). Linear equations obtained from asymptomatic patients showed the size of occluder =1.121×the maximum ASD diameter of TTE measured +6.414. Conclusions: There is no correlation between the symptoms with the expanded diameter and the maximum diameter of left umbrella's surface after released. The Postoperative discomfort symptoms is significantly correlated to the thickness of the occluder and the value of i. It is suggested that headache could be induced by the oversized occlude, thus choosing the appropriate size of the occluder is essential to reduce the occurrence of postoperative headache symptoms. Increasing the size of occluder because of worrying about the abscission and removal of the occlude is unreasonable. The antiplatelet therapy should also be strengthened to reduce the occurrence of symptoms and improve the symptoms of the patients if the occluder's size is too large. This regression equation (The size of occluder =1.121 × the maximum ASD diameter of TTE measured +6.414) could be used as a reference for the suitable selection of ASD occluder.

[Thoughts on the reform of preventive medicine education in the context of new medicine]

Talent training is the core and foundation of public health system construction. Shortage of talents in the field of disease prevention and public health exposed by COVID-19 pandemic highlights the importance of developing preventive medical education. This article analyzes the challenges of medical education in the dilemma of "separation of medical treatment and prevention", and the new requirements for preventive medical education in the construction of New Medicine under the Healthy China strategy. Four aspects including stepping up the resource allocation and investment, educating responsible public health professionals, the education of all medical students who implement the core competence of public health, and the establishment of a continuing education system for preventive medicine have been considered. A series of specific suggestions are put forward including the establishment of a full-chain closed-loop research system to support the cultivation of top-notch innovative public health talents, strengthening the assessment of core public health capabilities for clinical medical professional admission, formulating a "medical and preventive integration" training program for primary health personnel, and implementing "combination of peace and war" public health personnel reserve system, with the purpose of providing reference for the reform and development of preventive medical education in China.

Evaluation of 3D Measuring Methods for Body Surface Damage and Scars

Objective To assess the accuracy and reliability of the two 3D measuring methods, structured-light scanning and single-camera photogrammetry in forensic body surface damage and scar measurement. Methods The measuring results of 86 injuries by the ruler method, structured-light scanning and single-camera photogrammetry were compared and evaluated. The area measuring results of 13 simulated scars by the structured-light scanning, single-camera photogrammetry, Photoshop lasso pixel method and PDF reading software were compared and evaluated. The time consumed was recorded. The known specification information of the stickers was used as the standard value to compare the measuring accuracy of the ruler method, structural-light scanning and single-camera photogrammetry, and to calculate the root mean square error （RMSE）. The consistency evaluation of intraclass correlation coefficient （ICC） for the repeatability of 3 measuring results obtained by different operators and the same operator. Results The differences in results of the two 3D measuring methods and the ruler method had no statistical significance; the differences between measuring results made by the structured-light scanning, single-camera photogrammetry and PDF reading software and that of the Photoshop lasso pixel method had no statistical significance. The post-processing of the single-camera photogrammetry consumed more time than that of other methods. When the long-distance group （10-40 cm） was measured, the results obtained by the ruler method were shorter than the standard value. The RMSE value results were structured-light scanning < single-camera photogrammetry < ruler method. The ICC value intragroup and intergroup were greater than 0.99. Conclusion Both structured-light scanning and single-camera photogrammetry can be applied in recording and measuring forensic body surface damage. The former has better performance in measurement accuracy and stability, while the latter has better color performance but longer post-processing time.

[Alternative donor HSCT for 109 children with acquired severe aplastic anemia: a single center retrospective analysis]

目的

了解替代供者（AD）移植一线治疗儿童再生障碍性贫血（AA）的疗效及安全性。

方法

回顾性分析2010年4月1日至2016年12月31日在上海儿童医学中心一线接受AD移植治疗的AA患儿临床资料，统计分析总生存（OS）率、植入成功率、移植物抗宿主病（GVHD）发生率等指标。

结果

共纳入109例患者，极重型AA（VSAA）32例，重型AA（SAA）64例，非重型AA（NSAA）伴输血依赖13例，中位年龄6（0.8~18）岁，其中44例患者接受全相合无关供者（MUD）移植，44例接受8–9/10位点不全相合无关供者（MMUD）移植，21例接受不全相合亲缘供者（MMRD）移植，所有患者均接受以外周血干细胞（PBSC）为主的移植，≥3个位点不合的单倍型移植加第三方脐血（UCB）一份。所有患者移植前均未接受过抗胸腺细胞球蛋白（ATG）治疗，并排除活动性感染。106例（97.2%）获造血重建，中性粒细胞中位重建时间为13（9~19）d，血小板中位重建时间为16（10~81）d。死亡13例，5年OS率为88.1%（95%CI 81.1%~91.4%），MUD、MMUD及MMRD三组患者OS率差异无统计学意义（P=0.361）。总体急性GVHD（aGVHD）及Ⅱ~Ⅳ度aGVHD发生率分别为74.3%和39.4%，总体慢性GVHD（cGVHD）和中度cGVHD发生率分别为30.7%和9.9%，无一例患者发生重度cGVHD。

结论

对于无同胞全相合供者的SAA/VSAA患儿，早期一线接受AD移植可能是一个选择，但需要进一步探索更有效的预防及治疗GVHD的措施。

[Effect of consolidation before allogeneic hematopoietic stem cell transplantation for non-favorable acute myeloid leukemia patients with first complete remisson and negative minimal residual disease]

目的

探讨异基因造血干细胞移植（allo-HSCT）前巩固化疗对第1次形态学完全缓解且微小残留病阴性（CR₁/MRD⁻）中/高危急性髓系白血病（AML）患者预后的影响。

方法

对2010年1月至2019年3月在CR₁/MRD⁻状态下接受allo-HSCT的155例中/高危AML（不含急性早幼粒细胞白血病）患者进行回顾性分析。

结果

全部155例患者中，102例获得CR₁/MRD⁻后接受移植前巩固化疗（巩固组），53例获得CR₁/MRD⁻后直接行allo-HSCT（非巩固组），两组中位年龄分别为39（18~56）岁、38（19~67）岁。巩固组、非巩固组移植后5年总生存率分别为（59.3±7.5）%、（62.2±6.9）%（P=0.919），无复发生存率分别为（53.0±8.9）%、（61.6±7.0）%（P=0.936），累积复发率分别为（21.9±5.4）%、（18.3±6.0）%（P=0.942），非复发死亡率分别为（22.4±4.3）%、（28.4±6.5）%（P=0.464）。多因素分析显示，移植前是否接受巩固化疗及其疗程（<2个/≥2个）对预后无显著影响。

结论

中/高危AML患者可在获得CR₁/MRD⁻后直接进行allo-HSCT。

Construction of arming Yarrowia lipolytica surface-displaying soybean seed coat peroxidase for use as whole-cell biocatalyst

Whole-cell biocatalysts could be used in wide-ranging applications. In this study, a new kind of whole-cell biocatalyst was successfully constructed by genetically immobilizing soybean seed coat peroxidase (SBP) on the cell surface of Yarrowia lipolytica Po1h, using a new integrative surface display expression vector (pMIZY05). The coding sequence of SBP was optimized and chemically synthesized, then inserted into pMIZY05 to generate expression plasmid pMIZY05-oEp. A DNA fragment corresponding to SBP and selection marker expression cassettes, without bacterial sequences, was released from pMIZY05-oEp by enzyme digestion and used to transform host yeast cells. A transformant (CM11) with a high recombinant SBP activity of 1571.9 U/mL was obtained, and recombinant SBP was proved to be successfully anchored on cell surface by testing the activities of different cellular fractions. After optimization of culture conditions, the recombinant SBP activity of CM11 was increased to 4187.8 U/mL. Afterwards, biochemical properties of the recombinant SBP were determined: optimum catalytic conditions were 37.5℃ at pH 3.5, and recombinant SBP exhibited high stability during thermal or acidic treatment. Recombinant activity of cell-displayed SBP was re-examined at optimum temperature and pH, which promoted an increase up to 4432.5 U/mL. To our knowledge, this represents the highest activity ever reported for heterologous expression of SBP. This study also provides a useful strategy for heterologous expression of proteins which could be toxic to intracellular content of host cells.

[Prognostic value of donor chimerism at +90 days after allogeneic hematopoietic stem cell transplantation in young patients with intermediate-risk acute myeloid leukemia]

Objective: To investigate the relationship between donor chimerism and relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: The clinical data of 105 patients with acute myeloid leukemia (AML) who underwent allo-HSCT and recurrence-free survival>90 days from January 2010 to January 2019 were retrospectively analyzed. The bone marrow samples were collected at 15, 30, 60, 90, 180, 270, 360 days after transplantation. Donor chimerism was detected by single nucleotide polymorphism (SNP) -PCR. Results: Of the 105 patients, 43 cases were male and 62 cases were female, with a median age of 38 (16-60) years. Till April 2019, the median follow-up was 843 (94-3 261) days. Ninety days after transplantation, 18 cases relapsed, 33 cases died, and 72 cases survived. The 3-year overall survival (OS) rate was (66.8±5.1) %, and the recurrence-free survival (RFS) rate was (65.1±5.0) %. Pre-transplant disease status, pre-transplant minimal residual disease (MRD) , and 90 day post-transplantation chimerism were independent risk factors related to RFS. The risk of recurrence was significantly increased in patients with a donor chimerism rate ≤97.24% at 90 days after transplantation[HR=6.921 (95%CI 2.669-17.950) , P<0.001], which was considered as a sign of early relapse. Conclusion: SNP-PCR is an applicable method for detecting donor chimerism in patients after allo-HSCT. Chimerism rate equal or less than 97.24% at 90 days after transplantation predicts a higher risk of relapse.

Search for Light Weakly-Interacting-Massive-Particle Dark Matter by Annual Modulation Analysis with a Point-Contact Germanium Detector at the China Jinping Underground Laboratory

We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6  GeV/c^{2} among WIMP AM measurements to date.

Change in the structural and functional properties of goat milk protein due to pH and heat

This study was carried out to investigate the effects of pH and heat on the structure and function of milk proteins by comparing goat milk treated under different pH and temperature conditions. The results showed that pH had a significant effect on the thermal stability of goat milk proteins, and the proteins were least thermally stable at pH 7.7. Except for the pH 6.9 goat milk, the surface hydrophobicities of the milk proteins at various pH values reached their maxima at 85°C. The particle size, zeta potential, and content of regular secondary structure also decreased significantly at 85°C, and the turbidity of milk proteins under alkaline pH conditions was lower than that under acidic conditions. It was concluded that alkaline conditions resulted in better emulsion stability and oil-holding capacity, and acidic conditions offered better foaming ability, foam stability, and water-holding capacity for goat milk protein during heat processing. It can also be seen that 85°C was the key temperature for milk proteins after changing the pH of the milk. This paper provides a theoretical basis for optimizing the processing conditions for goat milk and the applications of goat milk proteins.

[Clinical and prognostic values of TP53 mutation in patients with acute myeloid leukemia]

Objective: To explore the clinical and prognostic values of TP53 gene mutation in patients with acute myeloid leukemia (AML) . Methods: A retrospective analysis of 265 newly diagnosed AML patients with next-generation sequencing (NGS) data in the Hematology Department of Changhai Hospital from January 2010 to January 2019 was performed. Mutation analysis was carried out by targeted sequencing technology including 200 hematological malignancy related genes. The association of TP53 mutation with clinical features was analyzed. Results: Alterations in TP53 were found in 20 (7.5%) patients, including 17 case (6.4%) of missense mutations, 2 cases (0.7%) of frame-shift deletion mutations and 1 case (0.4%) of splicing sites mutation. A total of 23 kinds of TP53 mutations were detected, most of them (16, 69.6%) were located in the DNA binding domain of exon 5-8, 4 in the DNA binding domain of exon 3-4, 2 in exon 10 and 1 in splice site, respectively. The median age of patients with TP53 alterations was higher than those without [52 (26-72) years old vs 45 (14-75) years old, P= 0.008]. The frequency of complex karyotypes was higher in patients with TP53 alterations than those without [45.0% (9/20) vs 6.1% (15/245) , P<0.001]. Median overall survival (OS) of patients with TP53 alterations was shorter than those without[14.1 (95%CI 6.78-21.42) months vs 31.4 (95%CI 13.20-49.59) months, P=0.029]. The OS of patients treated with "Decitabine + CAG" was superior than that of patients treated with "3 + 7" regimen [30.0 (95%CI 27.35-38.84) months vs 12.5 (95%CI 5.80-19.19) months, P=0.018]. Multivariate analysis indicated that TP53, DNMT3A and USH2A alterations, WBC ≥ 12.45×10(9)/L had negative impacts on OS. Conclusion: The frequency of TP53 mutation was 7.5% in our cohort. Most mutations were located in the DNA binding domain. TP53 alterations were strongly associated with older age, complex karyotype and shorter OS. Decitabine-based induction chemotherapy and hematopoietic stem cell transplantation may improve OS, more cases and/or multicenter randomized studies are needed for further confirmation.

[LncRNA HULC promots HCC growth by downregulating miR-29]

Objective: To explore the effects of lncRNA HULC on hepatocellular carcinoma (HCC) growth by down-regulating miR-29. Methods: The expression levels of HULC and miR-29 in HCC tissues and cells were detected by real-time quantitative PCR (RT-qPCR), and the correlation analysis was performed. After HCC cells were transfected with HULC overexpressed plasmid or siRNA, the expressions of miR-29 and its target gene SETDB1 were determinate by RT-qPCR. According to the bioinformatic prediction of the miR-29 binding site in the HULC sequence, the report gene plasmids were constructed. The HCC cells were co-transfected with miR-29 mimics or miR-29 inhibitor, and the HULC targeted regulation of miR-29 was verified by dual luciferase reporter assay. The effect of miR-29 on the HULC-mediated proliferation in HCC cells was detected by cell count kit 8 (CCK-8) experiment. Expression of tumor proliferation antigen Ki-67 was detected by RT-qPCR.The Hep3B cells were inoculated in mice and miR-29 mimics and miR-29 negative control (NC) further injected into the lesions. The tumor volume was observed, and the expressions of tumor proliferation antigen ki-67 in tumor tissues were detected by immunohistochemical staining. Results: The expression of HULC was significantly up-regulated while the expression of miR-29 was significantly down-regulated in HCC tissues and cells (P<0.01). The level of HULC was negatively correlated with miR-29 in tumor tissues (r=-0.754, P<0.01) and HCC cells (r=-0.865, P<0.05). The in vitro experiments showed that, compared with the blank control group, the expression of miR-29 in HULC overexpressed Huh7 cells was significantly reduced, while the mRNA level of miR-29 target gene SETDB1 was increased (P<0.01). The expression of miR-29 was significantly increased in HULC deleted Hep3B cells, while the mRNA expression of SETDB1 was decreased (P<0.01). Double luciferase reporter gene assay showed that miR-29 mimics significantly inhibited the luciferase activity of Hep3B cells transfected with HULC wide type (psi-HULC-WT) plasmid but had no effect on Hep3B cells transfected with mutant plasmid (psi-HULC-Mut). However, the miR-29 inhibitor antagonized the inhibitory effect of miR-29 mimics on luciferase activity of psi-HULC-WT (P<0.01). Cell proliferation experiments showed that, compared with the control group, the proliferation ability of miR-29 mimics overexpressed Huh7 cells was significantly reduced.After 24, 48 and 72 hours of treatment, the proliferation rates of Huh7 cells in the HULC overexpressed group were (43.87±3.82)%, (83.45±7.46)% and (123.34±8.67)%, respectively, significantly higher than (13.45±1.77)%, (23.54±1.37)% and (38.21±2.09)% of control group (P<0.05). After treatment for 48 and 72 hours, the proliferation rates of miR-29 mimics transfected Huh7 cells were (57.10±1.94)% and (73.76±3.46)%, respectively, significantly lower than (83.45±7.46)% and (123.34±8.67)% of control group (P<0.05). After treatment for 48 and 72 hours, the proliferation rates of Huh7 cells transfected with miR-29 mimics and miR-29 inhibitor group were (76.45±3.24)% and (89.37±4.37)%, respectively, significant higher than (57.10%±1.94)% and (73.76±3.46)% of the control group (P<0.05). After 48 h transfection, the expression of Ki-67 in Huh7 transfected with miR-29 mimics was significantly inhibited compared with the control group (P<0.01). However, the expression of Ki-67 mRNA was increased in Huh7 cells transfected with miR-29 inhibitor (P<0.01). The results of in vivo experiments showed that the tumor volumes of the control group, miR-29 mimics group and miR-29 mimics + miR-29 inhibitors group were (504.0±19.6) mm(3), (310.0±24.3) mm(3) and (483.7±21.2) mm(3), respectively. Injection of miR-29 mimics reduced while miR-29 inhibitor promoted tumorigenesis ability of Huh7 in nude mice (P<0.01). The immunohistochemical staining showed that the average optical density values of Ki-67 protein in tumor tissues of the control group, miR-29 mimics group and miR-29 analogue+ miR-29 inhibitor group were 0.65±0.08, 0.36±0.07 and 0.56±0.06, respectively. The expression level of Ki-67 protein in miR-29 mimics group was significantly reduced (P<0.01) while increased in the miR-29 mimics+ miR-29 inhibitor group (P<0.01). Conclusion: LncRNA HULC promotes HCC growth by down-regulating miR-29.

P4622Prediction of in-hospital bleeding for AMI patients undergoing PCI using machine learning method

Background

Prediction of in-hospital bleeding is critical for clinical decision making for acute myocardial infarction (AMI) patients undergoing percutaneous coronary intervention (PCI). Machine learning methods can automatically select the combination of the important features and learn their underlying relationship with the outcome.

Objective

We aim to evaluate the predictive value of machine learning methods to predict in-hospital bleeding for AMI patients.

Methods

We used data from the multicenter China Acute Myocardial Infarction (CAMI) registry. We randomly partitioned the cohort into derivation set (75%) and validation set (25%). Using data from the derivation set, we applied a state-of-art machine learning algorithm, XGBoost, to automatically select features from 106 candidate variables and train a risk prediction model to predict in-hospital bleeding (BARC 3, 5 definition).

Results

16736 AMI patients who underwent PCI were consecutively included in the analysis, while 70 (0.42%) patients had in-hospital bleeding followed the BARC 3,5 definition of bleeding. Fifty-nine features were automatically selected from the candidate features and were used to construct the prediction model. The area under the curve (AUC) of the XGBoost model was 0.816 (95% CI: 0.745–0.887) on the validation set, while AUC of the CRUSADE risk score was 0.723 (95% CI: 0.619–0.828).

Relative contribution of the 12 most important features Feature Relative Importance Direct bilirubin 0.078 Heart rate 0.077 CKMB 0.076 Creatinine 0.064 GPT 0.052 Age 0.048 SBP 0.036 TG 0.035 Glucose 0.035 HCT 0.031 Total bilirubin 0.030 Neutrophil 0.030

ROC of the XGBoost model and CRUSADE

Conclusion

The XGBoost model derived from the CAMI cohort accurately predicts in-hospital bleeding among Chinese AMI patients undergoing PCI.

Acknowledgement/Funding

the CAMS innovation Fund for Medical Sciences (CIFMS) (2016-12M-1-009); the Twelfth Five-year Planning Project of China (2011BAI11B02)