[Research progress of cardiovascular disease risk prediction models among patients with chronic kidney disease].

Patients with chronic kidney disease (CKD) have a relatively high risk of cardiovascular disease (CVD). Risk stratification guided by CVD risk prediction models is essential for managing CKD populations. We reviewed the outcome events, predictive variables, modeling methods, and predictive performance of CVD risk prediction models in CKD populations. We found a large variability in predictive outcomes, number of predictors, and sample sizes across studies. The models tended to overestimate the CVD risk of CKD populations. There are few independently validated or constructed CVD risk prediction models for CKD populations in developing countries, and in particular, there is a lack of independent external validation studies of model calibration. Future studies should comply with the reporting standards of risk prediction models to better support the application of CVD risk prediction models for CKD populations.

[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.

[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.

Riemann-Hilbert approach to two-component modified short-pulse system and its nonlocal reductions.

In this paper, a Riemann-Hilbert approach to a two-component modified short-pulse (mSP) system on the line with zero boundary conditions is developed. A parametric representation of the solution to the related Cauchy problem is obtained. Four nonlocal integrable reductions, namely, the real reverse space-time nonlocal focusing and defocusing mSP equations and the complex reverse space-time nonlocal focusing and defocusing mSP equations, are studied in detail. For each case, soliton solutions are presented, and, unlike their local counterparts, the nonlocal equations exhibit certain novel properties induced by the impact of nonlocality.

[Association of BMI with acute exacerbation in mild to moderate chronic obstructive pulmonary disease patients in community: a prospective study].

Objective: BMI may play a protective role in reducing the mortality rate of patients with chronic obstructive pulmonary disease (COPD), but its effect on acute exacerbation of COPD remain unclear. Methods: Subjects were selected from the COPD patients registration system established in 2014 in Pudong new district, Shanghai. COPD patients from 8 communities were selected by cluster sampling and follow up was conducted prospectively for 18 months. Basic information and BMI were obtained from baseline survey, and acute exacerbations were collected during follow-up. The association between BMI and risk of acute exacerbation was evaluated by using multiple negative binomial regression. Results: Among 328 community COPD patients, 295 who completed the follow up were included in the analysis, in whom 96.3% (284/295) were mild COPD patients. During the follow-up, 11.1% (33/295) of the patients reported acute exacerbation. The results of multiple negative binomial regression suggested that, the risk for acute exacerbation decreased with the increase of BMI (IRR=0.85, 95%CI:0.73-0.98), overweight patients with BMI ≥25.0 kg/m2 (IRR=0.36, 95%CI:0.13-0.91) or moderate BMI (T2 vs. T1, IRR=0.31, 95%CI:0.11-0.77) had lower risk for acute exacerbation compared with the patients with normal or low BMI. BMI had a linear correlation with the risk of acute exacerbation. Conclusion: The risk for acute exacerbation in patients with mild or moderate COPD in communities decreased with the increase of BMI, and being overweight might be a protective factor for the acute exacerbation of COPD.

[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.

[Effectiveness of different screening strategies for type 2 diabete on preventing cardiovascular diseases in a community-based Chinese population using a decision-analytic Markov model].

OBJECTIVE: To evaluate the effectiveness of different screening strategies for type 2 diabetes to prevent cardiovascular disease in a community-based Chinese population from economically developed areas based on the Chinese electronic health records research in Yinzhou (CHERRY) study. METHODS: A Markov model was used to simulate different systematic diabetes screening strategies, including: (1) screening among Chinese adults aged 40-70 years recommended by the 2020 Chinese Guideline for the prevention and Treatment of Type 2 Diabetes (Strategy 1); (2) screening among Chinese adults aged 35 to 70 years recommended by the 2022 American Diabetes Association Standard of Medical Care in Diabetes (Strategy 2); and (3) screening among Chinese adults aged 35-70 years with overweight or obesity recommended by the 2021 United States Preventive Services Task Force Recommendation Statement on Screening for Prediabetes and Type 2 Diabetes (Strategy 3). According to the guidelines, individuals who were screened positively (fasting plasma glucose ≥ 7.0 mmol/L) would be introduced to intensive glycemic targets management (glycated hemoglobin < 7.0%).The Markov model simulated different screening scenarios for ten years (cycles) with parameters mainly from the CHERRY study or published literature. Number of cardiovascular disease events or deaths could be prevented and number needed to screen (NNS) were calculated to compare the effectiveness of the different strategies. One-way sensitivity analysis on the sensitivity of screening methods and probabilistic sensitivity analysis on uncertainties of diabetes incidence, the sensitivity of screening methods, and intensive glycemic management effects were conducted. RESULTS: Totally 289 245 Chinese adults aged 35-70 years without cardiovascular diseases or diagnosed diabetes at baseline were enrolled. In terms of the number of cardiovascular disease events could be prevented, Strategy 1 for systematic diabetes screening among the adults aged 35-70 years was 222 (95%UI: 180-264), Strategy 2 for systematic diabetes screening among the adults aged 40-70 years was 227 (95%UI: 185-271), and Strategy 3 for systematic diabetes screening among the adults aged 35-70 years with obesity or overweight (body mass index ≥ 24 kg/m2) was 131 (95%UI: 98-164), compared with opportunistic screening. NNS per cardiovascular disease event for the strategies 1, 2 and 3 were 1 184 (95%UI: 994-1 456), 1 274 (95%UI: 1 067-1 564) and 814 (95%UI: 649-1 091), respectively. Compared with Strategy 1, NNS per cardiovascular disease event for Strategy 2 increased by 90 (95%UI: -197-381) with similar effectiveness of cardiovascular prevention; however, NNS per cardiovascular disease event for Strategy 3 was reduced by 460 (95%UI: 185-724) in contrast to the Strategy 2, suggesting that the Strategy 3 was more efficient. The results were consistent in multiple sensitivity analyses. CONCLUSION: Systematic screening for diabetes based on the latest guidelines in economically developed areas of China can reduce cardiovascular events and deaths. However, merely lowering the starting age of screening from 40 to 35 years seems ineffective for preventing cardiovascular disease, while screening strategy for Chinese adults aged 35-70 years with overweight or obesity is recommended to improve efficiency.

[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.

[Applications of Markov model for cost-effectiveness analysis of screening in epidemiology].

Cost-effectiveness analysis of screening in epidemiology is essential for public health decision-making. This paper describes the general principles, basic steps involved in implementation, analytic methods and other related issues of Markov model. Based on a practical research case of evaluating the cost-effectiveness of primary open-angle glaucoma screening in a Chinese population, key points in applications of Markov model for cost-effectiveness analysis of screening were discussed in detail, including model development, parameters definition, available software, base case analysis, sensitivity analysis and the interpretation of the results. For better supporting evidence-informed decision making in public health, future studies should be aware of the accuracy of parameters in Markov models and the transparency of the models and results, as well as complying with the relevant reporting standards.

[Effectiveness of different screening strategies for cardiovascular diseases prevention in a community-based Chinese population: A decision-analytic Markov model].

OBJECTIVE: To evaluate the potential effectiveness of different screening strategies for cardiovascular diseases prevention in a community-based Chinese population from economically developed area of China. METHODS: Totally 202 179 adults aged 40 to 74 years without cardiovascular diseases at baseline (January 1, 2010) were enrolled from the Chinese electronic health records research in Yinzhou (CHERRY) study. Three scenarios were considered: the screening strategy based on risk charts recommended by the 2020 Chinese guideline on the primary prevention of cardiovascular diseases in Chinese adults aged 40-74 years (Strategy 1); the screening strategy based on the prediction for atherosclerotic cardiovascular disease risk in China (China-PAR) models recommended by the 2019 Guideline on the assessment and management of cardiovascular risk in China in Chinese adults aged 40-74 years (Strategy 2); and the screening strategy based on the China-PAR models in Chinese adults aged 50-74 years (Strategy 3). According to the guidelines, individuals who were classified into medium- or high-risk groups after cardiovascular risk assessment by the corresponding strategies would be introduced to lifestyle intervention, while high-risk population would take medication in addition. Markov model was used to simulate different screening scenarios for 10 years (cycles), using parameters mainly from the CHERRY study, as well as published data, Meta-analyses and systematic reviews for Chinese populations. The life year gained, quality-adjusted life year (QALY) gained, number of cardiovascular disease events/deaths could be prevented and number needed to be screened (NNS) were calculated to compare the effectiveness between the different strategies. One-way sensitivity analysis on uncertainty of cardiovascular disease incidence rate and probabilistic sensitivity analysis on uncertainty of distributions for the hazard ratios were conducted. RESULTS: Compared with non-screening strategy, QALYs gained were 1 433 [95% uncertainty interval (UI): 969-1 831], 1 401 (95%UI: 936-1 807), and 716 (95%UI: 265-1 111) for the Strategies 1, 2, and 3; and the NNS per QALY in the above strategies were 141 (95%UI: 110-209), 144 (95%UI: 112-216), and 198 (95%UI: 127-529), respectively. The Strategies 1 and 2 based on different guidelines showed similar effectiveness, while more benefits were found for screening using China-PAR models in adults aged 40-74 years than those aged 50-74 years. The results were consistent in the sensitivity analyses. CONCLUSION: Screening for cardiovascular diseases in Chinese adults aged above 40 years seems effective in coastal developed areas of China, and the different screening strategies based on risk charts by the 2020 Chinese guideline on the primary prevention of cardiovascular diseases or China-PAR models by the 2019 Guideline on the assessment and management of cardiovascular risk in China may have similar effectiveness.

Darboux transformation of the generalized mixed nonlinear Schrödinger equation revisited.

In this paper, we present an explicit Darboux transformation of the generalized mixed nonlinear Schrödinger (GMNLS) equation. The compact determinant representation of the n-fold Darboux transformation of the GMNLS equation is constructed and the nth-order solution is built. We further prove that only the even-fold Darboux transformation and the even-order solution of the GMNLS equation can, respectively, be reduced to the Darboux transformation and solution of the Kundu-Eckhaus equation. Furthermore, two different kinds of explicit one-soliton solutions of the GMNLS equation are constructed and discussed.

[Application of the China-PAR stroke risk equations in a rural northern Chinese population].

OBJECTIVE: To validate five-year risk prediction models for stroke in a contemporary rural Northern Chinese population. METHODS: Totally 6 483 rural adults aged 40 to 79 years without cardiovascular diseases were enrolled at baseline between June and August 2010, and followed up through January 2017. Expected prediction risk using the China-PAR (prediction for atherosclerotic cardiovascular disease risk in China) stroke risk equations were compared with the new Framingham stroke risk profile (FSRP). The recalibrated models were applied by adjusting the five-year baseline survival rate and the mean score to our rural northern Chinese population, while keeping other coefficient parameters the same as the original models. Kaplan-Meier analysis was used to obtain the observed event (nonfatal or fatal stroke) rate for the five years, and the expected-observed ratios were calculated to evaluate overestimation or underestimation in the cohort. The models were assessed by discrimination C statistic, calibration χ2, and calibration charts and plots for illustration as well. RESULTS: Over an average of (5.83 ± 1.14) years of the follow-up in this validation cohort with 6 483 rural Chinese participants, 438 subjects deve-loped a first stroke event. Recalibrated China-PAR stroke risk equations and FSRP well-performed for predicting five-year stroke risk in men, and had C statistics of 0.709 (95%CI, 0.675 - 0.743) and 0.721 (95%CI, 0.688 - 0.754), with calibration χ2 values being 5.7 (P = 0.770) and 13.6 (P = 0.137), respectively. However, both China-PAR and FSRP overestimated stroke events by 11.6% and 30.0% in women, and had C statistics of 0.713 (95%CI, 0.684-0.743) and 0.710 (95%CI, 0.679-0.740), respectively. Calibration χ2 values in women were 12.5 (P = 0.188) for China-PAR and 24.0 (P = 0.004) for FSRP. In addition, the calibration charts and plots illustrated good agreement between the observations and the predictions only in the China-PAR stroke risk equations, especially for men. CONCLUSION: In this validation cohort of rural northern Chinese adults, the China-PAR models had better performance of five-year stroke risk prediction than the FSRP, indicating that recalibrated China-PAR stroke risk equations might be appropriate tools for risk assessment and primary prevention of stroke in China.

MiR-140-3p overexpression activates the Wnt signaling pathway to promote fracture healing.

OBJECTIVE: To study the mechanism of micro ribonucleic acid (miR)-140-3p participating in the regulation of fracture healing in rats. MATERIALS AND METHODS: A total of 50 male Sprague-Dawley (SD) rats were randomly divided into five groups, namely, group A [phosphate-buffered saline (PBS)] (n=10), group B (miR-140-3p mimics) (n=10), group C [ mimics negative control (NC)] (n=10), group D [antisense oligonucleotide (ASO)-miR-140-3p] (n=10), and group E (ASO NC) (n=10). A rat model of fracture was established on all the rats through the operation. From the successful establishment of the model, the rats in group A were intraperitoneally injected with 50 µL PBS (2 nmol) once a week for 6 weeks, and those in group B, C, D, and E were injected with equivalent volume of miR-140-3p mimics, mimics NC, ASO-miR-140-3p, and ASO NC, respectively, once a week since the successful establishment of model for 6 weeks. The fracture healing in the rats was evaluated via imaging. Meanwhile, Real Time-Polymerase Chain Reaction (RT-PCR) was applied to detect the expression of miR-140-3p in the five groups. Wnt and ß-catenin expressions in the five groups were detected by means of Western blotting (WB). Alkaline phosphatase (ALP) and its quantized statistical value in the five groups were detected through immunohistochemical staining. RESULTS: The expression of miR-140-3p was stimulated in miR-140-3p mimics group and inhibited in ASO-miR-140-3p group. The detection of the miR-140-3p expression level in the five groups via RT-PCR showed that miR-140-3p mimics group had a remarkably higher miR-140-3p expression than the other four groups. The differences were statistically significant (p<0.05). The WB assay verified that the Wnt and ß-catenin expressions in miR-140-3p mimics group were notably higher than those in control groups, and there were statistically significant differences (p<0.05). Compared with those in the groups injected with PBS, ASO miR-140-3p, mimics NC, and ASO NC, there were evidently more callus tissues, better healed and more blurred fracture lines, as well as no translocation and looseness of internal fixation, in the group injected with miR-140-3p mimics, suggesting that the stimulation of the miR-140-3p expression promotes the fracture healing in the rats. The results of immunohistochemical staining indicated that the number of ALP-positive osteoblasts in the rats in miR-140-3p mimics group was increased markedly in comparison with that in the remaining groups (p<0.05), implying that the differentiation of osteoblasts in the rats was affected in miR-140-3p mimics group. CONCLUSIONS: The overexpressed miR-140-3p in the rats with fracture can promote fracture healing by activating the Wnt signaling pathway.

[Analysis on the consistency and timeliness of death data gathered from different sources in the residents of Beijing].

Objective: To further improve the quality of mortality data for Beijing residents, through describing and analyzing the current death data gathered from different sources in Beijing. Methods: Data on death of the Beijing residents from Beijing Public Security Bureau, Beijing Civil Affairs Bureau and Beijing Centers for Disease Control and Prevention (BJCDC) were collated and compared. Timeliness of related data from the three different sources were described and analyzed. The overall consistency and reported timeliness of data from the three sources appear good, but the consistency on the causes of death needs to be improved. Result: Numbers of deaths from the three different sources were 95 318, 130 906 and 160 779 respectively, with 387 003 in total. Data from the Beijing Public Security Bureau and BJCDC seemed better in terms of integrity and accuracy. Data from the Beijing Public Security Bureau had the highest filling rate of ID card number while data from the Beijing Civil Affairs Bureau had the best timeliness. The most informative source of data was from the BJCDC. Conclusion: The overall quality of the exchanged death data from Beijing Public Security Bureau, Beijing Civil Affairs Bureau and BJCDC appeared good but remained some areas for improvement.

[Influencing factors on healthy life expectancy in adults in Beijing].

OBJECTIVE: To understand the main influencing factors related to healthy life expectancy (HALE) among adults in Beijing. METHODS: The calculation on health-adjusted life expectancy was performed by Sullivan METHODS. Data from the self-reported health survey program on adults in Beijing 2012 was gathered. Hierarchical ordered probit model was used to estimate the severity-weighted prevalence of disability and then combined with the period life table to obtain the HALE. Factors associated with the severity-adjusted prevalence of the disabled were analyzed under the generalized additive models (GAM). RESULTS: The main influencing factors of HALE would include age (t=40.351, P<0.001), sex (t=9.689, P<0.001), levels of education (t=5.021, P< 0.001), exercise (t=5.487, P<0.001) and alcohol intake (t=-2.380, P=0.017) etc. The influence of per capita monthly income (χ(2) =3.949, P=0.044) showed as non-linear. CONCLUSIONS: Levels of income would directly influence the severity-weighted prevalence of the disability, which also affecting the HALE. Programs on improving healthy life style and health care in women should be promoted.

[Analysis on causes of death of residents in Beijing, 1965-1974].

OBJECTIVE: To fill up the absence of data on causes of death of urban residents in Beijing during 1965-1974 and provide evidence for the similar study in other areas. METHODS: All possible sources for death data during 1965-1974 were identified through expert consultations and record search. Stratified sampling was conducted to collect the death data of urban residents during this period in Beijing. The mortality rate, death cause constituent and rank of death causes were used in this descriptive analysis. RESULTS: A total of 11 668 records of deaths from 1965 to 1974 were collected from 10 local police stations in urban area of Beijing. The top 10 death causes in the urban residents were heart disease, tumor, cerebrovascular disease, accidental injury, respiratory system disease, digestive system disease, communicable disease and parasitic disease, nervous system disease, urogenital and reproductive system disease, endocrine and nutrition metabolic diseases. The deaths caused by these diseases accounted for 84.19% of the total deaths. Accidental injury accounted for 13.22% of the total deaths, which was significantly higher than that in either 1964 or 1975, two years before and after this period(P<0.01). Suicide accounted for 54.47% of the total accidental injury deaths. For men, accidental injury was the leading death cause, followed by cancer and heart disease; for women, heart disease, cancer and cerebrovascular disease were the top three death causes. CONCLUSION: The major death cause in urban residents changed from infectious diseases to chronic and non-communicable diseases during 1965-1974. A remarkable high proportion of deaths caused by accidental injury was due to the historical background during that period in Beijing, China.

Nonlinear Schrödinger equation: generalized Darboux transformation and rogue wave solutions.

In this paper, we construct a generalized Darboux transformation for the nonlinear Schrödinger equation. The associated N-fold Darboux transformation is given in terms of both a summation formula and determinants. As applications, we obtain compact representations for the Nth-order rogue wave solutions of the focusing nonlinear Schrödinger equation and Hirota equation. In particular, the dynamics of the general third-order rogue wave is discussed and shown to exhibit interesting structures.

In vitro hepatic differentiation of mesenchymal stem cells from human fetal bone marrow.

We examined whether human fetal mesenchymal stem cells (FMSCs) derived from fetal bone marrow were able to differentiate into functional hepatocyte-like cells in vitro. The surface phenotype of FMSCs was characterized by flow cytometry. To induce hepatic differentiation of FMSCs, we added hepatocyte growth factor, basic fibroblast growth factor and oncostatin M into the cell culture medium. After 21 days of hepatocyte induction, FMSCs expressed the hepatocyte-specific markers, alpha-fetoprotein and cytokeratin 18, as demonstrated by immunofluorescence staining. Differentiated FMSCs also demonstrated in vitro functions characteristic of liver cells, including albumin production, urea secretion and glycogen storage. In conclusion, fetal bone marrow-derived FMSCs are able to differentiate into functional hepatocytelike cells and may serve as a source of cells for liver disease therapy.

Prostanoids mediate the protective effect of trefoil factor 3 in oxidant-induced intestinal epithelial cell injury: role of cyclooxygenase-2.

Trefoil factors are small peptides found in several mammalian tissues including gut, respiratory tract and brain. Their physiological function is not well understood. Among them, trefoil factor 3 (intestinal trefoil factor) is known to be cytoprotective in the gut. However, the molecular mechanism and secondary mediators of trefoil factor 3 action are not known. In the present study, we examined whether the cyclooxygenase pathway is involved in trefoil factor 3 action. We showed that trefoil factor 3 significantly induces the production of prostaglandin E(2) and prostaglandin I(2) in IEC-18 cells (an intestinal epithelial cell line) in a dose dependent manner. Western blot and immunohistochemistry revealed that trefoil factor 3 (2.5 microM) up-regulates the expression of cyclooxygenase-2 but not cyclooxygenase-1 in IEC-18 cells. Treating cells with trefoil factor 3 (10 microM) significantly attenuated reactive oxygen species-induced IEC-18 cell injury. This effect is blocked by NS-398 (10 microM), a selective cyclooxygenase-2 inhibitor. Moreover, we demonstrated that exogenously administered carbacyclin (1 microM, a stable analogue of prostaglandin I(2)) and/or prostaglandin E(2) (1 microM) caused a significant reduction of reactive oxygen species-induced cell injury, mimicking the effect of trefoil factor 3. In summary, our results indicate that trefoil factor 3 activates cyclooxygenase-2 in intestinal epithelium to produce prostaglandin I(2) and prostaglandin E(2), which function as survival factors and mediate the cytoprotective action of trefoil factor 3 against oxidant injury.

Negative regulation of macrophage activation in response to IFN-gamma and lipopolysaccharide by the STK/RON receptor tyrosine kinase.

IFN-gamma primes macrophages for antimicrobial activity, increased killing of intracellular pathogens, and Ag processing and presentation to lymphocytes by cooperating with a second signal (provided by LPS or endogenous TNF-alpha) to promote increased proinflammatory cytokine production, NO production, and MHC class II expression. Macrophage-stimulating protein (MSP) suppresses NO production by activated peritoneal macrophages in vitro. Furthermore, targeted deletion of the receptor for MSP, stem cell-derived tyrosine kinase receptor (STK/RON), resulted in increased production of NO by activated macrophages both in vitro and in vivo. Here we demonstrate that expression of STK in RAW264.7 cells resulted in suppression of NO production following IFN-gamma+/- LPS stimulation in the presence of MSP, reflecting a decrease in the levels of inducible NO synthase (iNOS) mRNA and protein, which was confirmed by decreased trans-activation of an iNOS reporter. The iNOS expression is regulated by the coordinate activity of the inducible transcription factors STAT-1, IFN response factor-1, and NF-kappaB. The presence of the STK receptor did not significantly alter the expression of the IFN-gamma receptor, STAT1 phosphorylation, or the up-regulation of IFN response factor-1 expression following IFN-gamma stimulation. However, nuclear translocation of NF-kappaB following stimulation of RAW cells with IFN-gamma and LPS was reduced in the presence of the MSP/STK signaling pathway. These results suggest that the negative regulation of macrophage responses by MSP/STK occurs at least in part via inhibition of costimulatory signals, resulting in NF-kappaB activation, that cooperate with IFN-gamma to promote activation.