[Analysis of the change in human resources of centers for disease control and prevention in different regions of China from 2010 to 2020].

Objective: To analyze the change in human resources within China's Centers for Disease Control and Prevention (CDC) from 2010 to 2020. Methods: The self-reported information from provincial, prefectural (city), and county (district) levels of China's CDC, covering employee counts, staff composition, professional qualifications, educational backgrounds, technical titles, and tenure, were extracted from the China Disease Prevention and Control Information System. The demographic context was provided by the annual population figures from the China Statistical Yearbook (2010-2020). The profile of CDC personnel was described, and the average annual percentage rate change (AAPC), average annual percentage rate change (APC), human resource agglomeration degree (HRAD) and the difference between HRAD and population agglomeration degree (PAD) were calculated. The Joinpoint regression model was used to analyze the time trend. Results: The decade under review witnessed a net increase of 17 300 active and 18 300 enrolled personnel in the CDC, surpassing the national population growth rate with AAPCs of 0.93% and 1.03%, respectively. This upward trajectory was statistically significant (P<0.05). The ratio of disease control personnel per 10 000 population escalated from 1.14 to 1.21. An initial decline in active CDC workforce density (from 1.31 to 1.27 per 10 000 population between 2010 and 2017) was followed by an increase (from 1.28 to 1.37 between 2018 and 2020), with APCs of -0.40% and 3.73%, respectively. The proportion of professional and technical staff in 2019 was highest in the eastern region (86.01%), followed by the western (83.75%) and central regions (79.54%). The period also saw an enhancement in the average academic degree (from 1.91 to 2.43 points) and professional title scores (from 1.39 to 1.53 points) of CDC personnel. While the average tenure in the eastern and western regions showed a slight decline, the central region experienced an increase, with HRAD values indicating a higher concentration in the eastern and central regions compared to the western region. The HRAD-PAD discrepancy revealed a negative value in the eastern region, nearing zero in the central and western regions. Conclusion: Between 2010 and 2020, China's CDC experienced notable growth in human resources and underwent structural optimization, albeit with significant regional disparities in concentration.

[Analysis of the status of excess heart age and its risk factors among residents aged 35 to 64 years in China].

Objective: To analyze the status of excess heart age and its risk factors among Chinese residents aged 35 to 64 years. Methods: The study subjects were Chinese residents aged 35 to 64 years who completed the heart age assessment by WeChat official account "Heart Strengthening Action" through the internet from January 2018 to April 2021. Information such as age, gender, body mass index (BMI), blood pressure, total cholesterol (TC), smoking history, and diabetes history was collected. The heart age and excess heart age were calculated according to the characteristics of individual cardiovascular risk factors and the heart aging was defined as excess heart age≥5 years and 10 years respectively. The heart age and standardization rate were calculated respectively based on the population standardization of the 7th census in 2021.CA trend test was used to analyze the changing trend of excess heart age rate and population attributable risk (PAR) was used to calculate the contribution of risk factors. Results: The mean age of 429 047 subjects was (49.25±8.66) years. The male accounted for 51.17% (219 558/429 047) and the excess heart age was 7.00 (0.00, 11.00) years. The excess heart age rate defined by excess heart age≥5 years and ≥10 years was 57.02% (the standardized rate was 56.83%) and 38.02% (the standardized rate was 37.88%) respectively. With the increase of the age and number of risk factors, the excess heart age rate of the two definitions showed an upward trend according to the result of the trend test analysis (P<0.001). The top two risk factors of the PAR for excess heart age were overweight or obese and smoking. Among them, the male was smoking and overweight or obese, while the female was overweight or obese and having hypercholesterolemia. Conclusion: The excess heart age rate is high in Chinese residents aged 35 to 64 years and the contribution of overweight or obese, smoking and having hypercholesterolemia ranks high.

[Association of plasma albumin and hypersensitive C-reactive protein with 5-year all-cause mortality among Chinese older adults aged 65 and older from 8 longevity areas in China].

Objective: To investigate the relationship of plasma albumin and hypersensitive C-reactive protein (Hs-CRP) with 5-year all-cause mortality among Chinese older adults aged 65 and older. Method: Data was collected in 8 longevity areas of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) study conducted by Chinese Center for Disease Control and Prevention and Peking University at baseline survey in 2012 and 2014, the participants enrolled in 2012 was followed-up in 2014 and 2017, the participants enrolled in 2014 was followed-up in 2017 only. Finally, 3 118 older adults aged 65 and older with complete information on albumin, Hs-CRP and body mass index (BMI) were included in this study. Plasma samples of older adults were collected for the detection of albumin and Hs-CRP at baseline survey. Survival status and follow-up time was recorded for all participants. All older adults were divided into 4 groups according to the levels of plasma albumin and Hs-CRP, and Cox proportional hazard models were constructed to assess their influence on the risk of all-cause mortality. Results: Among 3 118 older adults included, the prevalence of hypoalbuminemia was 10.1% (316/3 118), and was 22.8% (711/3 118) for elevated Hs-CRP. During 10 132 person-years of follow-up, 1 212 participants died. Participants with hypoalbuminemia had increased risk of all-cause mortality, with an hazard ratio (HR) and 95% confidential interval (CI) of 1.18 (1.01-1.38), compared to participants with normal plasma albuminemia; participants with elevated Hs-CRP had increased risk of all-cause mortality, with an HR (95%CI) of 1.18 (1.04-1.35), compared to participants with normal plasma Hs-CRP. Participants with normal plasma albumin and elevated Hs-CRP, with hypoalbuminemia and normal Hs-CRP, with hypoalbuminemia and elevated Hs-CRP also had increased risk of all-cause mortality when compared to those with normal plasma albumin and normal Hs-CRP, the HR (95%CI) were 1.16 (1.01-1.34), 1.11 (0.91-1.37) and 1.43 (1.11-1.83), respectively. Conclusion: Hypoalbuminemia and elevated Hs-CRP were responsible for increased risk of 5-year all-cause mortality among Chinese older adults from 8 longevity areas.

[Evaluation on the effect of salt reduction intervention among fourth-grade primary school students and their parents in Shandong Province].

In order to evaluate the intervention effect of the school-based salt reduction model, 28 primary schools were selected in Shandong Province in September 2014 and randomly divided into intervention group (1 361 students, 1 306 parents) and control group (1 364 students,1 340 parents). A series of "small hands and big hands" salt reduction intervention activities were conducted in intervention group for 8 months. After the intervention, the total awareness rate of salt reduction knowledge, the total holding rate of related beliefs and the total reporting rate of related behaviors were 70.65%, 80.30% and 67.03% among students, and 85.66%, 93.77% and 87.93% among parents, in the intervention group, which were higher than those in the control group (37.12%, 66.52% and 50.07% among students; 55.11%, 87.52% and 57.96% among parents) (all P values <0.05). The school-based salt reduction model is effective and feasible.

Treatment of vitiligo with 308-nm excimer laser: our experience from a 2-year follow-up of 979 Chinese patients.

BACKGROUND: The 308-nm excimer laser had been proved to be a time-efficient and potent therapeutic alternative for the management of vitiligo. Different results had been reported in different ethnic populations. OBJECTIVE: To investigate the efficacy and related contributing factors of 308-nm excimer laser in Chinese vitiligo patients. METHODS: A total of 979 Chinese patients (3478 lesions) with progressive-stage vitiligo who had received 308-nm excimer laser treatment were recruited from the vitiligo clinic of Shandong Provincial Hospital of Dermatology &Venereology from 2012 to 2014. Efficacy of treatment was evaluated at the end of session by two independent dermatologists based on the before and after images taken. Repigmentation was graded on a 4-point scale: grade 1, poor repigmentation (0-25%); grade 2, moderate repigmentation (26-50%); grade 3, good repigmentation (51-75%); grade 4, excellent repigmentation (76-100%). RESULTS: The mean grade of repigmentation was 2.29, 44.22% showed less than 25% repigmentation, 16.27% showed 26-50% repigmentation, 5.95% showed 51-75% repigmentation and 33.55% showed more than 76% repigmentation. The repigmentation of facial lesions was better than lesions located elsewhere (P < 0.0001), the best response was noted in the periorbital region, while lesions on hands and feet showed poor repigmentation (P < 0.0001). The degree of repigmentation was negatively correlated with disease duration (r = -0.268, P < 0.001), age (r = -0.095, P < 0.001) and shape of lesions (r = -0.114, P < 0.001), whereas it was positively correlated with treatment frequency (r = 0.270, P < 0.001). Lesions with concurrent poliosis were more likely resistant to treatments. CONCLUSION: 308-nm excimer laser appears to be an effective and safe treatment in Chinese vitiligo patients. The clinical response and treatment efficacy was affected by many factors such as age, affected anatomical area, shape of the lesion, disease duration and treatment frequencies.

[Follow-up study of body mass index and risk of cognitive impairment among elderly adults aged ≥65 years old from longevity areas of China].

Objective: To discuss the relationship between body mass index (BMI) and cognitive impairment among elderly adults aged ≥65 years old from longevity areas of China. Methods: A total of 2 439 elderly adults from 8 longevity areas were included in our baseline survey by answering questionnaire and taking body measurements and blood biochemical examinations in 2012. In the follow-up study in 2014, we studied the cognitive impairment status among the 1 135 elderly adults aging ≥65 years old. Multivariate logistic regression model was used to analyze the relationship between BMI and cognitive impairment risk. Results: 113 participants were defined as cognitive impairment, with a positive rate at 10.0%. The positive rate in group of underweight, normal weight, and overweight and obese elderly were 22.2% (51/230), 7.5% (47/629), 5.4% (15/276). The rate of cognitive impairment in groups of low BMI (<19.7 kg/m(2)), middle BMI (19.7-23.1 kg/m(2)) and high BMI (>23.1 kg/m(2)) were separately 17.7% (66/372), 7.1% (27/379) and 5.2% (20/384) (P<0.001). Every 1.0 kg/m(2) increase in BMI, the risk of cognitive impairment would significantly decreased by 7% (RR(95%CI): 0.93(0.87-0.99)). Compared with participants with middle BMI level, the group of low BMI participants was associated with a significantly increased risk of cognitive impairment (RR (95% CI): 1.98(1.14-3.44)); while there was no significant association was observed in the high BMI group (RR(95%CI): 1.15(0.57-2.32)). Compared with elderly in normal weight, the elderly with under weight was in higher risk of cognitive impairment (RR (95%CI: 2.19(1.31-3.66)) and there was no significant association found between the elderly with overweight (RR(95%CI): 1.18(0.58-2.38)). Conclusion: Among the elderly ≥65 years old from longevity area, low BMI level and underweight were associated with the increased risk of cognitive impairment.

[Relationship between the successful aging and survival status among the elderly from longevity areas in China].

Objective: To explore the relationship between successful aging (SA) index and the survival status among elderly from longevity areas of China. Methods: A total of 2 296 old people aged ≥65 years old from 8 longevity areas were enrolled in our baseline survey in 2012. The information of demographics characteristic, life style, self-assessed health and mood or emotional state, cognitive function, abilities of daily living and physical activity were collected by questionnaire. There were 891 SA people in total, whose SA score was 4-5. 891 SA and 1 396 non-SA participated in the follow-up study in 2014. Finally, 860 SA and non-SA people were matched by orientation analysis. A Cox proportional hazards model was used to explore the relationship between successful aging index and survival status. Results: After 2 years of follow-up, a total of 1 442 elderly survived, with an average baseline age at (83.69±10.81) years old and 278 elderly people died, with an average baseline age at (93.41±9.05) years old. The mortality rate was 16.16% (278/1 720) in total, and it was 13.14% (113/860) in SA group, which was lower than it in non-SA group (19.19%, 165/860), and the difference was statistically significant (P=0.001). The analysis of the multivariate Cox regression showed that SA was the protective factor of the survival of the elderly after age and sex adjusted. Compared to the non-SA group, the risk of mortality rate in SA group decreased by 38%, the HR (95% CI) was 0.62 (0.49-0.79). Conclusion: The mortality rate in the SA group was low in the longevity areas in China; compared with non-SA group, the death rate in SA group reduced by 38%.

[Study on handgrip strength of elderly ≥60 years old from longevity areas in China].

Objective: To assess the status of handgrip strength of elderly population from longevity areas in China, and to analyze the correlative factors of handgrip strength of elderly people. Methods: Data from Chinese Longitudinal Healthy Longevity Survey (CLHLS) in 2012 was used, from which1 967 participants aged ≥60 years old with valid data of grip strength value from 8 Chinese longevity areas were included. Information on demographics characteristic, life style and health status was collected using questionnaires. The handgrip strength of both left and right hands were measured by grip dynamometer. The different characteristics of group of participants with different grip strength were compared and then analyzed by adopting the Cumulative odds Logistic regression model to identify main factors associated with hand grip strength. Results: The P(50) (P(25)-P(50)) of hand grip strength of elderly people from the eight longevity areas was 20 (11-28) kg; The hand grip strength of males was 26 (18-34) kg, which was higher than that of females(14 (9-20) kg) (P<0.001). Cumulative odds Logistic regression model showed that the hand grip strength of females was lower than males, whose ß value (95%CI) was-1.22 (-1.43--1.00). The elderly who was at a higher age, smoking, drinking or with anemia, had a comparatively lower handgrip strength, whose ß (95%CI) value were separately-0.08(-0.09~-0.07),-0.29(-0.56~-0.02),-0.54(-0.80~-0.28), and-0.41(-0.62~-0.20). And the elderly who had a higher boby mass index, drinking tea and outdoor activities, had a comparatively higher handgrip strength, whose ß(95%CI) value were separately 0.28 (0.15-0.40), 0.25(0.03-0.47) and 0.51(0.30-0.71). Conclusion: Age and gender were the main correlative factors, lifestyles and physical conditions might also be correlative factors of hand grip strength of the elderly from longevity areas in China.

[Association between biomarkers and activities of daily living in the elderly ≥65 years old from longevity areas in China].

Objective: To explore the association between biomarkers and activities of daily living (ADL) in the elderly over 65 years old from longevity areas in China. Methods: A total of 2 439 people from 8 longevity areas were included in our baseline survey in 2012. Using questionnaires, body measurements, and blood biochemical examinations, information on demographics characteristic, life style, ADL, blood pressure and biomarkers were collected. Based on these six items of ADL (bathing, dressing, indoor activities, toileting, eating, bowel and bladder control), we constructed a dichotomous indicator for ADL. A respondent was defined as ADL disabled if any difficulty in one or more of the above six activities was reported. Information were collected in the follow-up in 2014 using the same questionnaires and examinations. We excluded information on the elderly who lacked ADL or biomarkers test results or with ADL disability at baseline study. Finally 938 elderly people over 65 years old were included in this analysis. Multivariate logistic regression model was used to analyze the influence factors of ADL disability. Results: During the 2-year follow-up, 100 (10.7%) participants developed into ADL disability, with a rate at 10.7%. Multivariate logistic regression analysis indicated that each year increase in age or each 1 mmHg (1 mmHg=0.133 kPa) increase in systolic blood pressure (SBP) would cause the risk of ADL disability to increase 9% or 1%, whose OR (95%CI) were separately 1.09 (1.06-1.12), 1.01 (1.00-1.02). Han nationality or cognitive impairment increased the risk of ADL disability, whose OR (95%CI) values were separately 4.90 (1.13-21.24), 2.47 (1.44-4.25), while increased lymphocyte count (>1.60×10(9)/L), being married, or participating in recreational activities decreased the risk of ADL disability, whose OR (95%CI) values were separately 0.51 (0.31-0.82), 0.52 (0.28-0.96), 0.43 (0.23-0.80). Conclusion: In the elderly elevated lymphocyte count was associated with lower risk of ADL disability. In addition, incresed age, increased SBP, unmarried, Han nationality or cognitive impairment were associated with the increasing risk of ADL disability in older people, while participating in recreational activities would reduce the risk.

[A perspective cohort study on influence factors of survival outcome among the elderly aged ≥80 years old from longevity areas in China].

Objective: To investigate the influence factors of survival outcome among elderly aged ≥80 years old. Methods: In baseline survey in 2009, 930 participants aged ≥80 years old were enrolled from 7 longevity areas, to collect the information of socioeconomic factors, life style, cognitive function, activities of daily living and diseases, as well as physical examination to test biomarkers of blood and urine. The survival status was followed up at 2012 and 2014 survey. Stepwise Cox proportional hazards models were used to screen influence factors of 5-year survival. Results: During 5 years of follow-up, 571 participants died, 133 participants were lost to follow up, and the all-cause mortality was 63.4%. In stepwise Cox proportional hazards models, male, unmarried, self-reported poor life quality, disability in daily life, cognitive impairment, cardiovascular and cerebrovascular diseases, chronic kidney diseases were risk factors for elderly survival outcome, with the HR (95%CI) at 1.75 (1.40-2.12), 1.49 (1.10-2.03), 1.40 (1.16-1.69), 1.37 (1.11-1.70), 1.51 (1.22-1.88), 1.62 (1.18-2.23) and 1.48 (1.23-1.77) respectively. Each 1 year increase in age corresponded to 4% increase in mortality risk (HR (95%CI)=1.04 (1.02-1.05)); each 1 kg/m(2) increase in BMI corresponded to 5% increase in mortality risk (HR (95%CI)=0.95 (0.93-0.98)); each 1.0×10(9)/L increase in total lymphocyte count (TLC) corresponded to 13% increase in mortality risk (HR (95%CI)=0.87 (0.76-0.99)). Additionally, the mortality risk decreased 19% (HR (95%CI)=0.81 (0.66-0.98)) in participants with regularly physical exercise compared to those without; and the mortality risk decreased 41% (HR (95% CI)=0.59 (0.40-0.88)) in participants with elevated triglycerides (TG, ≥2.26 mmol/L) compared to those without. Conclusion: In Chinese longevity areas, some nutritional and immune indices such as relatively higher level of BMI, TLC and TG were independent protective factors for 5-year survival outcome, which was different from general adults and younger elderly.

[In vivo and in vitro experimental studies of remote digital control endovascular robotic system in interventional angiography].

Objective: To investigate the feasibility of the remote control endovascular robotic system in interventional angiography. Method: The endovascular robotic system Heifetz™ and the matched steerable catheter Mirage™ were used to cannulate all the target vessels in the vascular model and cerebral arteries originated from the aorta of Bama mini-pigs under fluoroscopic guidance. The technical success rate, cannulation time and exposure dose were all collected and compared with the result of using conventional techniques. Result: All the target vessels were successfully cannulated.The average cannulation time for the steerable catheter into left subclavian artery, left common carotid artery, brachiocephalic artery, right common carotid artery and right subclavian artery in the vascular model was (21.3±2.8)s, (28.8±5.2)s, (17.7±2.6)s, (31.5±5.1)s and (24.2±3.7) s, respectively, while the average exposure dose was (9.3±1.2)mGy, (12.4±2.2)mGy, (7.4±1.2)mGy, (14.2±2.5)mGy and( 10.4±1.9)mGy, respectively. The endovascular robotic system completed the cerebral angiography in Bama mini-pigs successfully. The average cannulation time for left innominate artery, right innominate artery, right subclavian artery, common internal carotid trunk, left internal carotid artery and right internal carotid artery was (41.5±6.8)s, (29.1±3.7)s, (40.7±5.5)s, (40.1±5.8)s, (59.6±9.0)s and( 60.3±10.1)s, respectively, while the average exposure dose was (40.6±6.5)mGy, (36.0±5.2)mGy, (39.8±6.1)mGy, (43.9±6.7)mGy, (51.0±7.4)mGy and( 50.1±7.8)mGy, respectively. There was no significant difference between robotic and conventional group in success rate, cannulation time and exposure dose. Conclusion: The remote digital control endovascular robotic system could cannulate the target vessel in both vascular model and complete the cerebral angiography in Bama mini-pigs, which shows the feasibility of using this robotic system in endovascular intervention procedures under remote control.

[Research progress of risk assessment model of type 2 diabetes mellitus].

Established models of type 2 diabetes mellitus(T2DM)are used to determine predictors with the aim of disease prevention. Established models are used to determine predictors, then assign risk scores or calculate the probability of T2DM development within a certain timeframe. A number of countries and regions have established T2DM risk assessment models, which can be divided into non-invasive and invasive tools, depending on whether they use routinely collected information or laboratory markers. Here, we review the latest progress of two assessment models at the national and international levels, and explore and summarize their applications. The noninvasive Finnish Diabetes Risk Score and the invasive Framingham model are widely used internationally. However, invasive models were more widely applied, as studies on T2DM risk assessment models started relatively late in China.

[Establishing a noninvasive prediction model for type 2 diabetes mellitus based on a rural Chinese population].

OBJECTIVE: To provide a noninvasive type 2 diabetes mellitus (T2DM) prediction model for a rural Chinese population. METHODS: From July to August, 2007 and July to August, 2008, a total of 20 194 participants aged ≥18 years were selected by cluster sampling technique from a rural population in two townships of Henan province, China. Data were collected by questionnaire interview, anthropometric measurement, and fasting plasma glucose and lipid profile examination. A total 17 265 participants were followed up from July to August, 2013 and July to October, 2014. Finally, 12 285 participants were selected for analysis. Data for these participants were randomly divided into a derivation group (derivation dataset, n= 6 143) and validation group (validation dataset, n=6 142) by 1∶1, respectively. Randomization was carried out by the use of computer-generated random numbers. A Cox regression model was used to analyze risk factors of T2DM in the derivation dataset. A T2DM prediction model was established by multiplying ß by 10 for each significant variable. After the total score was calculated by the model, analysis of the receiver operating characteristic (ROC) curve was performed. The area under the ROC curve (AUC) was used for evaluating model predictability. Furthermore, the model's predictability was validated in the validation dataset and compared with the Finnish Diabetes Risk Score (FINDRISC) model. RESULTS: A total 779 of 12 285 participants developed T2DM during the 6-year study period. The incidence rate was 6.12% in the derivation dataset (n=376) and 6.56% in the validation dataset (n=403). The difference was not statistically significant (χ(2)=1.00, P=0.316). A total of four noninvasive T2DM prediction models were established using the Cox regression model. The ROCs of the risk score calculated by the prediction models indicated that the AUCs of these models were similar (0.67-0.70). The AUC and Youden index of model 4 was the highest. The optimal cut-off value, sensitivity, specificity, and Youden index were scores of 25, 65.96%, 66.47%, and 0.32, respectively. Age, sleep time, BMI, waist circumference, and hypertension were selected as predictive variables. Using age<30 years as reference, ß values were 1.07, 1.58, and 1.67 and assigned scores were 11, 16, and 17 for age groups 30-44, 45-59, and ≥60 years, respectively. Using sleep time<8.0 h/d as reference, the ß value and assigned score were 0.27 and 3, respectively, for sleep time ≥10.0 h/d. Using BMI 18.5-23.9 kg/m(2) as reference, ß values were 0.53 and 1.00 and assigned scores 5 and 10, respectively, for BMI 24.0-27.9 kg/m(2), and ≥28.0 kg/m(2). Using waist circumference <85 cm for males/< 80 cm for females as reference, ß values were 0.44 and 0.65 and assigned scores 4 and 7, respectively, for 85 cm ≤ waist circumference <90 cm for males/80 cm≤ waist circumference <85 cm for females, and waist circumference ≥90 cm for males/≥85 cm for females. Using nonhypertension as reference, the respective ß value and assigned score were 0.34 and 3 for hypertension. The AUC performance of this model and the FINDRISC model was 0.66 and 0.64 (P=0.135), respectively, in the validation dataset. CONCLUSION: Based on this cohort study, a noninvasive prediction model that included age, sleep time, BMI, waist circumference, and hypertension was established, which is equivalent to the FINDRISC model and applicable to a rural Chinese population.

Screening for genes that are differentially-expressed between gastric cancer cells and gastric tumor sphere cells using the gene chip technique.

The purpose of this study was to screen for genes that were differentially expressed between a human gastric carcinoma cell line (HGC-27) and their tumor spheres, using the gene chip technique. The HGC-27 cells and tumor sphere cells were cultured in vitro in a sterile environment. Total RNA was extracted from both samples and purified using a standard TRIzol reagent. Total RNA was then hybridized onto a GeneChip, according to the standard protocols provided by the manufacturers of the GeneChip IVT Express Kit. The resulting fluorescence signals were analyzed and displayed using the Cluster and Treeview software programs. Under the criteria for significant differential expression (≥2-fold difference), 610 up- and 1135 down-regulated genes were identified in tumor sphere cells, compared to HCG-27 cells. These genes were involved in cell growth, signal transduction, tumorigenesis, and many other functional aspects of tumor cells. In conclusion, a number of genes were differentially expressed in tumor sphere cells compared to HCG-27 cells. In addition, we identified a close correlation between tumor sphere cells and tumorigenesis.

[Prediction model related to 6-year risk of frailty in older adults aged 65 years or above in China].

Objective: To develop a prediction tool for 6-year incident risk of frailty among Chinese older adults aged 65 years or above. Methods: Data from the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2018 was used, including 13 676 older adults aged 65 years or above who were free of frailty at baseline. Key predictors of frailty were identified via the least absolute shrinkage and selection operator (LASSO) method, and were thereafter used to predict the incident frailty based on the Cox proportional hazards regression model. The model was internally validated by 2 000 Bootstrap resamples and evaluated for the performance of discrimination and calibration using the area under the receiver operating characteristic curve (AUC) and calibration curve, respectively. The net benefit of the developed prediction tool was evaluated by decision-curve analysis. Results: The M(Q1, Q3) age and follow-up time of the participants were 81.0 (71.0, 90.0) years and 6.0 (4.1, 9.2) years, respectively. A total of 4 126 older persons (30.2%) were recorded with frailty incidents during the follow-up, with the corresponding incidence density of 41.8/1 000 person-years. A total of 15 key predictors of frailty were selected by LASSO, namely, age, sex, race, education years, meat consumption, tea drinking, performing housework, raising domestic animals, playing cards or mahjong, and baseline status of visual function, activities of the daily living score, instrumental activities of the daily living score, hypertension, heart disease, and self-rated health. The prediction model was internally validated with an AUC of 0.802, with the max Youden's index of 0.467 at a risk threshold of 19.0%. The calibration curve showed high consistency between predicted probabilities and observed proportions of frailty events. The decision curve indicated that higher net benefits could be obtained via the prediction model than did strategies based on intervention in all or none participants for any risk threshold less than 59%, and the model-based net benefit was estimated to be 0.10 at a risk threshold of 19.0%. Conclusions: The herein developed 6-year incident risk prediction model of frailty, based on easily accessible questionnaires and physical examination variables, has good predictive performance. It has application potential in identifying populations at high risk of incident frailty.

Novel single nucleotide polymorphisms of the bovine methyltransferase 3b gene and their association with meat quality traits in beef cattle.

DNA methylation is essential for adipose deposition in mammals. We screened SNPs of the bovine DNA methyltransferase 3b (DNMT3b) gene in Snow Dragon beef, a commercial beef cattle population in China. Nine SNPs were found in the population and three of six novel SNPs were chosen for genotyping and analyzing a possible association with 16 meat quality traits. The frequencies of the alleles and genotypes of the three SNPs in Snow Dragon beef were similar to those in their terminal-paternal breed, Wagyu. Association analysis disclosed that SNP1 was not associated with any of the traits; SNP2 was significantly associated with lean meat color score and chuck short rib score, and SNP3 had a significant effect on dressing percentage and back-fat thickness in the beef population. The individuals with genotype GG for SNP2 had a 25.7% increase in lean meat color score and a 146% increase in chuck short rib score, compared with genotype AA. The cattle with genotype AG for SNP3 had 35.7 and 24% increases in dressing percentage and 28.8 and 29.2% increases in back-fat thickness, compared with genotypes GG and AA, respectively. Genotypic combination analysis revealed significant interactions between SNP1 and SNP2 and between SNP2 and SNP3 for the traits rib-eye area and live weight. We conclude that there is considerable evidence that DNMT3b is a determiner of beef quality traits.

[Design of non-metallic crown for primary molars and analyzation of stress distribution: a finite element study].

Objectives: To study the design of nonmetallic crowns for deciduous molars by means of computer aided design and to analyze the key parameters of the nonmetallic crowns of deciduous molars using finite element method. Methods: The three-dimensional model of a mandibular second primary molar was constructed by using a micro-CT system. The thickness of the crown was limited to 0.5 mm and four different crown shapes (chamfer+anatomic, chamfer+non-anatomic, knife edge+anatomic and knife edge+non-anatomic) were designed. Then, the crown shape was limited as chamfer+non-anatomic and five different thicknesses of the crown (0.50, 0.75, 1.00, 1.25, 1.50 mm) were designed, and three different materials, including polyetherketoneketone (PEKK), polymethylmethacrylate (PMMA) resin and resin-infiltrated ceramic, were applied to make the crown. Stress distribution and fatigue of each component of the model under vertical and oblique loadings were analyzed by using finite element method. Non-axial retention analysis was performed on chamfer+non-anatomic crowns, made of PMMA resin, with thicknesses of 0.50, 0.75, 1.00, 1.25 and 1.50 mm. Results: Among the four crown shape designs, the chamfer+non-anatomic type crown showed the lowest von Mises stress and the highest safety factor. By comparing three different materials, the resin-infiltrated ceramic group showed obvious stress concentration on the buccal edge of the crown and the PEKK group showed stress concentration in the adhesive layer. Results of non-axial retention analysis showed that the torques required by the crowns with five thicknesses at the same rotation angle were as follows: 4 856.1, 4 038.1, 3 497.3, 3 256.3 and 3 074.3 N⋅m, respectively. The comparison of areas of the adhesives fracture among groups were as follows: 0.5 mm group < 0.75 mm group < 1.00 mm group < 1.25 mm group < 1.50 mm group. Conclusions: In the design of nonmetallic crowns for primary molars, the edge of the crown should be designed as chamfer, the shape of the inner crown should be non-anatomical and the minimum preparation amount of the occlusal surface should be 1.00 mm. Among the three materials, PMMA resin, of which elastic modulus is similar to the dentin and the dental adhesive, might be the most suitable material for the crowns of primary molars.

Zoledronate inhibits intimal hyperplasia in balloon-injured rat carotid artery.

BACKGROUND AND OBJECTIVE: Zoledronate has been reported to inhibit the proliferation, adhesion and migration of vascular smooth muscle cells. In the present study, we assessed whether systemic and local delivery of zoledronate would be sufficient to prevent intimal hyperplasia. METHODS: Twenty-four male Sprague-Dawley rats were assigned into four groups: non-treated group, systemic zoledronate-treated group, local collagen-treated group and local zoledronate-treated group. All four groups underwent balloon injury to the right common carotid artery. The left uninjured carotid arteries of the non-treated group were considered as normal artery samples. Twenty-one days after arterial injury and treatment, the right and left common carotid arteries were fixed, sectioned, stained and measured by computer-aided image analysis. RESULTS: At 3 weeks, there was a 59% reduction of the intima/media area ratio in the systemic zoledronate-treated group compared with the non-treated group (P < 0.01). There was an 87% reduction of the intima/media area ratio in the local zoledronate-treated group compared with the local collagen-treated group (P < 0.01). CONCLUSIONS: Both systemic and local delivery of zoledronate correspond to a significant reduction in intimal hyperplasia seen at 3 weeks.

Short communication: Distribution of recessive genetic defect carriers in Chinese Holstein.

In dairy cattle, 4 important recessive hereditary diseases exist: complex vertebral malformation (CVM), bovine leukocyte adhesion deficiency (BLAD), citrullinemia (CTLN), and deficiency of uridine monophosphate synthase (DUMPS). Holstein Associations in developed countries have established monitoring systems for such disorders in Holstein bulls for decades. Over the past decades, China has continuously imported Holstein semen and embryos, mainly from North America but also from Europe. The dissemination of such genetic defects was undetermined until now, although efforts were taken to develop molecular techniques and detect carriers for CVM and BLAD in small populations of Chinese dairy cattle. Thus, herein we extensively screened 732 proven bulls participating in artificial insemination programs and 136 young bulls entering progeny test from 15 bull stations in China for CVM, BLAD, CTLN, and DUMPS. The proportion of carriers of the defects was found to be 7.72, 1.38, 0.23, and 0.12%, respectively. Given our findings, early diagnostic and monitoring systems on recessive inherited disorders among proven and young bulls entering the national genetic improvement programs for dairy cattle of China should be established immediately, in which a series of measures will be taken to prevent further spreading of such disorders and gradually eliminate them in the dairy cattle population in China.