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In order to study the influence of the peripheral substituent position of sorbitol acetal molecule on its nucleation effect, three sorbitol acetal nucleating agents which are isomers of each other were synthesized. The crystallization process of polypropylene (PP) before and after modification was analyzed, and the effects of sorbitol acetal nucleating agent on the morphology, structure and properties of PP was studied. The results show that the three sorbitol acetal nucleating agents are α crystalline nucleating agents, among which the para-substituted sorbitol acetalization nucleating agent has the best performance, and has the best improvement effects on the optical properties and mechanical properties of PP. The haze is reduced from 78% to 16%, and the crystal grains are the most uniform and dense, and the crystallization temperature is the highest. The para-substituted sorbitol acetal nucleating agent is an efficient α crystalline transparent nucleating agent for PP. [ABSTRACT FROM AUTHOR]

The components of traditional Chinese medicine(TCMCs) are the basic unit of raw materials for Chinese medicines, and their physical and chemical properties directly affect the choice of dosage forms and the optimization of prescriptions. However, most of TCMCs are multi-component complex systems, and the characterization of their overall properties is still in the exploration stage. On the basis of biological activity, the representative components are determined, and then the individual characteristics are fitted with the weight coefficient of efficacy contribution rate, which may provide reference for characterizing the overall properties of TCMCs. In this study, with the pharmacological effects of isoproterenol(ISO)-induced myocardial ischemia in rats as the indicators, the pharmacodynamic contribution rates of three representative components of chishao terpene glucoside components(CSTGCs) were evaluated by the normalization weighting method. The contribution rates of paeoniflorin, paeoniflorin and benzoylpaeoniflorin were 54.87%, 32.46% and 12.67%, respectively. The oil-water partition coefficients of paeoniflorin, albiflorin, benzoylpaeoniflorin in water and buffer solutions with different pH values were measured, and the oil-water partition coefficients of CSTGCs were characterized by the weight of their pharmacodynamics contribution rate. The results showed that the apparent oil-water partition coefficient(log P) of CSTGCs in the phosphate buffer system such as n-octanol-water(pH 2.0, 2.5, 5.0, 5.8, 6.8) were 0.18-0.22, indicating that CSTGCs have common absorption and low permeability, providing basis for the preparation of CSTGCs.

Objective: To investigate the correlation of serum calcium levels and the risks of diabetes mellitus (DM) in middle-aged elderly men., Methods: A total of 3386 male subjects aged 40-79 years were selected from two local communities of Beijing using stratified random sampling for this cross-sectional survey. The survey was conducted using questionnaires, and all the subjects underwent physical examination and blood tests of serum calcium, vitamin D and other biochemical parameters. The subjects were divided into normal glucose group, prediabetic group and diabetic group to compare their blood biochemical parameters and analyze the risk factors of diabetes., Results: The prevalence of diabetes and pre-diabetes was 32.31% in the 3386 subjects surveyed. Serum calcium, vitamin D and Creatinine (Cr) levels were significantly higher in pre-diabetic and diabetic groups than in the non-diabetic group (P/0.05), and age, body mass index, serum calcium, vitamin D, and Cr levels differed significantly between the former two groups (P/0.05). The prevalence of diabetes increased significantly with serum calcium level (P/0.05). Logistic regression analysis showed that age, body mass index, serum calcium, and serum vitamin D levels were independent risk factors for diabetes (P/0.05)., Conclusion: Male diabetic patients have abnormal serum calcium levels. An increased age and increased serum calcium levels are associated with higher risks of diabetes, and age, serum calcium, serum vitamin D, Cr, and body mass index are all risk factors of diabetes in men.

Objective: To investigate the correlation of serum sex hormones and parathyroid hormone (PTH) with the biochemical markers of bone turnover in aged men., Methods: We collected the laboratory data of 465 men aged 60- 93 (73. 1 +/- 8. 3) years old, who came for routine physical examinations in our hospital. We obtained the levels of serum follicle- stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), testosterone (T), sex hormone binding globulin (SHBG), PTH, 25-hydroxy-vitamin D3 (25(OH) D3), and bone turnover markers C-terminal telopeptide of type I collagen (CTX), osteocalcin (OC) and amino-terminal propeptide of type I procollagen (PINP). We also determined free testosterone (FT) , bioactive testosterone (BT) , testosterone secretion index (TSI) and FT index (FTI), and analyzed the correlation of each index with the biochemical markers of bone turnover., Results: The concentrations of serum FSH, LH, and SHBG increased, while the levels of FT, BT, TSI, FTI, PTH, CTX, OC and PINP decreased with age, especially in those over 80 years old (P <0.05). PTH was positively correlated with CTX, OC and PINP (r =0. 227, 0. 269 and 0. 162, P <0. 01), even after the adjustment for age, while SHBG negatively correlated with OC (r = -0. 100, P <0.05). The bone turnover markers increased with the elevation of the PTH quartiles, with significant differences between the first and the fourth quartile (P <0. 01). Multiple stepwise regression analysis showed that age was correlated inversely with CTX, OC and PINP ( beta = -0. 126, -0. 141 and -0. 122, P <0.05) , PTH positively with the three markers (beta = 0. 196, 0.279 and 0.189; P <0. 001), and SHBG negatively with OC ( beta = -0. 100, P <0.05) ., Conclusion: Aging is the fundamental cause of reduced bone turnover in aged men. The levels serum PTH and SHBG are significantly associated with the biochemical markers of bone turnover.

Objective: To explore the influencing factors of glycemic variability in elderly patients with type 2 diabetes., Methods: A total of 337 elderly patients received continuous glucose monitoring (CGM) from January 2007 to January 2011. The evaluation variables of glycemic variability included standard deviation of blood glucose (SDBG), mean amplitude of glycemic excursion (MAGE), absolute means of daily differences (MODD) and postprandial glucose excursion (PPGE). The normal reference value of glycemic variability was defined according to the diagnostic criteria of Chinese Diabetes Society guideline., Results: The difference of glycemic variability was compared by gender, age and diabetic duration. The values of SDBG, MAGE, MODD and PPGE in females were all higher than those in males (P < 0.05) and no difference existed between various age groups. The level of glycemic variability increased gradually with the extension of diabetic duration (P < 0.01). Logistic regression analysis showed that gender (MAGE: OR = 0.44, P = 0.023; SDBG: OR = 0.39, P = 0.023), diabetic duration (MAGE: OR = 1.58, P = 0.006; SDBG: OR = 2.42, P < 0.001) and HbA1c (MAGE: OR = 2.44, P < 0.001; SDBG: OR = 2.68, P < 0.001) were significant influencing factors of glycemic variability (MAGE/SDBG) in elderly patients with type 2 diabetes (P < 0.05), but not age, body mass index (BMI) or diabetic neuropathy., Conclusion: Gender, diabetic duration and HbA1c are significant influencing factors of glycemic variability while age, BMI or diabetic neuropathy has no association with glycemic variability in elderly patients with type 2 diabetes.

Objective: To compare the different establishing conditions of hyperinsulinemic-euglycemic clamp technique among the groups of normal glucose tolerance (NGT), hyperinsulinemia with normal glucose (HINS) and impaired glucose tolerance (IGT)., Methods: The hyperinsulinemic-euglycemic clamp technique was applied to the study of methodology in 10 NGT, 11 HINS and 10 IGT subjects. Different establishing conditions were compared through variance analysis (ANOVA) among three groups. And the influencing factors resulting in these differences were analyzed through stepwise regression analysis., Results: The serum insulin concentration of three groups were acutely raised and maintained at above 100 mU/L. During the steady stage, the blood glucose level remained stable and all coefficient variations were under 5%. The secretion of endogenous insulin and hepatic glucose production were completely inhibited during the test. Under these steady-state hyperinsulinemic-euglycemic conditions, the glucose infusion rate (M value) was equal to glucose disposal rate by all tissues in body, M value of three groups were as follows: (11.6 ± 1.7), (6.1 ± 1.9) and (6.0 ± 1.5) mg×kg(-1)×min(-1). During clamping, the peak and steady-state serum insulin concentrations of IGT and HINS groups were significantly higher than those of NGT group. Although the peak and steady-state serum insulin concentration of HINS group were higher than those of IGT group, the differences had no statistical significance (P = 0.34, 0.11). The independent influencing factor of peak serum insulin concentration was waist-to-hip ratio (WHR) while the independent influencing factors of steady-state serum insulin concentration included insulin metabolic clearance rate (MCR) and body mass index (BMI). The peak and steady-state serum insulin concentrations were not the independent influencing factors of M value., Conclusion: During the establishment of hyperinsulinemic-euglycemic clamp technique, the differences in peak and steady-state serum insulin concentrations existed among NGT, HINS and IGT groups. But the differences do not influence the use of M value in the evaluation of insulin resistance.

Objective: To study the impact of different insulin levels on the conversion from impaired glucose tolerance (IGT) to type 2 diabetes mellitus (T2DM), through analysis of different glycometabolism condition among quinquagenarian population., Methods: Subjects enrolled were Beijing habitants who received annual physical examination [including oral glucose tolerance test (OGTT)] in the Chinese PLA General Hospital from 2005 - 2007. According to the OGTT results, the subjects were divided into three groups, including normal glucose tolerance-non-hyperinsulinemia group (NGT-NHIns), IGT-hyperinsulinemia group (IGT-HIns) and IGT-non-hyperinsulinemia group (IGT-NHINS). The prognosis between the year 2009 and 2010 of the three groups was observed. Hyperinsulinemia was diagnosed with fasting serum insulin ≥ 15 mU/L and/or 2-hour serum insulin ≥ 80 mU/L after glucose loading., Results: The rate of case number of conversion to T2DM in IGT-NHIns group (42/133) was higher than that in IGT-HIns group (24/154) or NGT-NHIns group (12/126). The HOMA insulin resistance index (HOMA-IR) of individuals with IGT-NHIns was lower than that of IGT-HIns [0.96 (0.40, 3.53) vs 2.04 (0.59, 23.20), P < 0.05], while whole body insulin sensitivity index (WBISI) was higher than that of IGT-HIns [7.48 (3.20, 31.35) vs 3.28 (0.86, 7.67), P < 0.05]. Modified β-cell function index (MBCI) and insulin secretion index (ISI) in IGT-NHIns was poorer than that of IGT-HIns respectively [2.57 (0.58, 10.98) vs 5.17 (1.04, 65.09); 7.66 (0.99, 28.40) vs 17.56 (4.18, 96.46), all P values < 0.01]., Conclusions: The risk of IGT-NHIns progressing into T2DM is higher than that of IGT-HIns. For the prevention of T2DM, individuals with IGT-NHIns should be paid more attention than keeping an eye on IGT-HIns patients. Early control of risk factors could protect β cell function and prevent the progression to T2DM.

Objective: To evaluate the diagnostic values of osteoporosis self-assessment tool for Asians (OSTA) in aged men., Methods: Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) in 382 male outpatients. Their data were collected. After excluding such influencing factors of BMD as diseases or drugs, they were divided into 3 groups according to the WHO osteoporosis diagnosis value or age. The correlation between OSTA index and BMD was analyzed by Spearman correlation. The concordance of OSTA and BMD were calculated and analyzed by a four-fold table., Results: The prevalence of osteoporosis was 9.42% and osteopenia 42.67%. Age increased gradually in the osteoporosis, osteopenia and normal bone mass groups. But OSTA index, BMD (including lumbar vertebrae L(1-4), femoral neck, trochanter and hip) and weight decreased gradually in those groups. The percent of normal bone mass decreased with advancing age. And the percentages were 60.68%, 51.97% and 33.33% respectively. Osteoporosis increased in the older group (> 80 years old) and the percentage was 24.64% accounting for 94.44% of all osteoporotic subjects. Judging by the OSTA index, the rate of low osteoporotic risk decreased with advancing age. But the rates of mid-risk and high-risk increased. The correlation coefficients of OSTA index and BMD in femoral neck, trochanter, hip and L(1-4) was 0.33, 0.28, 0.29 and 0.06 respectively. And the correlation between OSTA index and BMD had statistical significance except for L(1-4). The sensitivity, specificity, coincidence and Youden index of OSTA index with a T score cutoff of -1 of BMD were 56.28%, 64.48%, 60.21% and 0.21 respectively versus 86.11%, 57.80%, 60.47% and 0.44 with a T score cutoff of -2.5., Conclusion: Correlation exists between OSTA index and BMD. The sensitivity, specificity and coincidence of OSTA index are excellent based upon the standard of BMD by DXA. It is a useful and simple diagnostic tool of osteoporosis.

Objective: To study the feasibility of using postprandial insulin (2hINS) and fasting insulin (FINS) on evaluation of insulin resistance, comparison was conducted between 2hINS and FINS on evaluation of cardiovascular risk factors., Methods: A survey were conducted among individuals in the community in May 2008 and data of routine clinical examination were collected. All subjects were investigated and received 75 g oral glucose tolerance test (OGTT), and fasting and OGTT2 h blood glucose as well as insulin concentrations were determined. Hyperinsulinemia was defined as a FINS or 2hINS concentration at or above the 95th percentile of the distribution among normal glucose tolerance individuals., Results: 1148 individuals were investigated and insulin concentration in male was similar to female. Prevalence of 2hHINS (40.8%) in individuals with abnormal glucose metabolism was higher than FHINS (18.4%, P < 0.01). The number of metabolic risk factors in subjects with 2hHINS was similar to subjects with FHINS. After adjustment by sex, age, BMI and waist circumference, partial correlation analysis showed that the correlation between 2hINS and 2hPG (r = 0.370) was higher than that of FINS and FPG (r = 0.104); FINS was higher correlated with TG and HDL- cholesterol than 2hINS, however, 2hINS was higher correlated with diastolic blood pressure, total cholesterol and LDL-cholesterol than FINS. Logistic regression analysis showed that FHINS and 2hHINS were both the independent risk factor of metabolic syndrome, the OR (95%CI) were 5.11 (2.953 - 8.842) and 3.46 (2.109 - 5.687)., Conclusion: 2hINS and FINS were both closely associated with cardiovascular risk factors. The correlation was inconsistent when 2hINS and FINS were related to different risk factors. The combination of 2hINS and FINS might be more helpful on evaluation of insulin resistance.

Objective: To study the correlation between hyperinsulinemia (HIns) and arteriosclerosis in one community in Beijing., Methods: Subjects who received arteriosclerosis screening in physical examination annually were studied. All subjects were received 75g oral glucose tolerance test (OGTT) to evaluate glucose metabolic level, and brachial-ankle pulse wave velocity (baPWV) examination to evaluate arteriosclerosis. The correlation between hyperinsulinemia and pulse wave velocity was analyzed., Results: Among all the 1046 subjects under investigation, baPWV of subjects with HIns was higher than subjects with normoinsulinemic (NIns) in different glucose metabolism status [normal glucose tolerance, (1381.2 ± 280.8) cm/s vs (1280.3 ± 218.7) cm/s; imparied glucose regulation, (1557.5 ± 319.3) cm/s vs (1474.7 ± 305.1) cm/s; diabetes, (1764.3 ± 476.6) cm/s vs (1664.2 ± 374.6) cm/s], especially in subjects with normal glucose tolerance (P < 0.01). The prevalence of cardiovascular risk factors in subjects with HIns was much higher than subjects with NIns (P < 0.01). Multiple logistic regression analysis showed that hyperinsulinemia was the risk factor of arteriosclerosis, and the OR (95%CI) of subjects with HIns was 1.91 (1.169 - 3.105, P < 0.01) as compared to the subjects with NIns., Conclusion: The subjects with HIns suffered from much more metabolic risk factors than NIns. Hyperinsulinemia that closely correlated with baPWV was a risk factor of arteriosclerosis.

Objective: To study the outcomes and influencing factors of the conversion from normal glucose tolerance-hyperinsulinemia (NGT-HINS) to diabetes in the population of a community in Beijing., Methods: All the subjects investigated received 75 g oral glucose tolerance test (OGTT) for diabetes screening carried out in May, 2006 and May, 2008. Data were calculated to analyze the outcomes and influencing factors of the conversion. HINS was diagnosed if fasting serum insulin≥15 mIU/L and/or 2-hour serum insulin after glucose loading≥80 mIU/L., Results: The prevalence of NGT-HINS in the community in 2006 and 2008 was 5.28% and 8.67% (P<0.01) respectively and that of diabetes mellitus (DM) and impaired glucose regulation (IGR) was 3.52%, 6.56% in 2006 and 4.42%, 6.47% in 2008. The probability of the conversion from NGT-HINS to IGR and DM was 18.6% and 2.3%, being much higher than that from normal glucose tolerance-normoinsulinemia (NGT-NINS) (5.4% and 0.7%, P<0.01). However, the probability of the conversion from NGT-HINS to DM was 2.3%, which was much lower than that from IGR (26.3%, P<0.01). The reason might be that individuals with NGT-HINS had a higher waist circumference, BMI, fasting plasma glucose, 2 h plasma glucose and TG but a lower HDL-C than individuals with NGT-NINS in 2006. The HOMA β-cell function index/HOMA insulin resistance index (HBCI/IR) of individuals with NGT-HINS was much lower than that of individuals with NGT-NINS, but much higher than that of individuals with IGR. Logistic regression analysis showed that age, TG and HBCI/IR were the major influencing factors of the conversion from NGT to glucose metabolic disorders., Conclusions: The probability of conversion from NGT to DM was increased remarkably when HINS was diagnosed. The reason might be that individuals with NGT-HINS suffered more metabolic risk factors and had a decreased β-cell function. Therefore, individuals with NGT-HINS should be paid attention to in diabetes prevention study.