ObjectiveTo explore the levels of serum glucose and insulin secretion function in people with different educational background of normal glucose tolerance and to investigate its relationship with educational levels. MethodsWe had telephone connections with normal fast glucose people who did health examination from January 2007 to January 2011, then the 75 g oral glucose tolerance test was performed and the level of insulin were measured. A total of 340 people with normal glucose tolerance who completed our examination and answered a questionnaire on lifestyle were included in our study. They were divided into three groups according to their educational levels. The levels of plasma glucose and insulin were measured in 92 high educational level participants, 68 middle educational level participants and 70 low educational level participants. We calculated homevstasis model assessment (HOMA)-S, HOMA-IR, and HOMA-β and compared differences between the three groups. ResultsWith the decline of educational levels, fasting plasma glucose, body mass index (BMI), fasting insulin, postprandial insulin, HOMA-β, and HOMA-IR gradually increased, while HOMA-S gradually decreased. The level of BMI, fasting insulin and HOMA-IR in high educational level group were significantly lower than those in low educational level group. The level of BMI, HOMA-IR in middle educational level group were significantly lower than those in low educational level group (P<0.05). Correlation analysis indicated that level of fasting plasma glucose was related to age, BMI, and educational levels. ConclusionWith the decline of educational levels, BMI and HOMA-IR increase, and HOMA-S decreases, which indicates that they already have differences in glucose metabolism and insulin secretion function in people with normal glucose tolerance, presaging that in the future the proportion of development of diabetes in the low educational level may increase.
ObjectiveTo isolate the tendon stem cells (TSCs) from rat patellar tendon and to investigate the effect of mechanical stretching on the expression of Sox-9. MethodsTSCs were isolated from Sprague Dawley rat (12 weeks old) patellar tendon by collagenase digestion and low density culture. The cell colony morphology and number were observed by crystal violet staining;the cell morphology was observed by inverted phase contrast microscope, and the immunophenotypes of mesenchymal stem cells (MSCs) were determined by flow cytometry. The TSCs at passage 3 was given the mechanical stretching at 4%, 0.17 Hz for 4 hours and 24 hours in the experimental group, and cells without stretching was used as control. The Sox-9 gene and protein expressions were detected by real-time fluorescence quantitative PCR and Western blot. ResultsPrimary cells showed clonal growth and star shape;after subculture, cells at passage 1 showed fibroblast-like shape. The cells formed cell colonies after 7 days;the expressions were positive for CD29, CD44, and CD90 and negative for CD45. The result of real-time fluorescence quantitative PCR showed that Sox-9 gene was down-regulated at 4 hours after mechanical stretching compared with control (P<0.05), and up-regulated at 24 hours after mechanical stretching when compared with control group (P<0.05). The result of Western blot showed that Sox-9 protein expression was lower at 4 hours after stretching, but higher at 24 hours after mechanical stretching than that in control group (P<0.05). ConclusionThe rat patellar TSCs can be isolated successfully, and mechanical stretching inhibits the Sox-9 expression, but the inhibited effect might stimulate the Sox-9 expression after the mechanical stretching effect disappears.