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[Objective] The aim of our study is to examine nodule prevalence in a population over 40 years old in order to explore the relation between prevalence of thyroid nodules and metabolic parameters.[Methods] A total of 1875 individuals who were over 40 years of age were received the questionnaire and underwent thyroid ultrasonography examinations.Height,weight,waist circumference,blood pressure were measured.Levels of fasting blood glucose,fasting serum insulin,glycated hemoglobin,blood lipids,thyroid stimulating hormone and free T4 were detected.Body mass index (BMI) and homeostasis model assessment-insulin resistance (HOMA-IR) were calculated.[Result] The study included a total of 1875 subjects (513 men and 1362 women).The age of subjects were between 41 and 113 years old,and the mean age was 57.4±7.1 years old.The prevalence of thyroid nodules was 51.2％,and the prevalence of thyroid nodules in women was significantly higher than that in men (53.4％ vs.45.2％,P=0.002).The prevalence of thyroid nodules was significantly higher in subjects with hypertriglyceridemia (59.2％ vs.49.5％,P=0.009) and hypertension (56.5％ vs.47.8％,P＜ 0.001).Result of multivariate binary logistic regression revealed that hypertension (OR=1.405,P=0.002),female sex (OR=1.490,P=0.001),older age (OR=1.028,P＜0.001),and hypertriglyceridemia (OR=1.589,P=0.005) were independent risk factors for thyroid nodules.The prevalence of thyroid nodules increased along with age,systolic blood pressure and serum triglyceride level.[Conclusion] The prevalence of thyroid nodules and metabolism-related diseases were high in population over 40 years old.After adjusted for age and sex,hypertriglyceridemia and hypertension were possible independent risk factors for thyroid nodules especially in women.In general,hypertriglyceridemia and hypertension might play an important role in the pathological process of thyroid nodules.
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<p><b>BACKGROUND</b>Some single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1alpha and type 2 diabetes in the southern Chinese population and to determine whether the common variants: Gly482Ser and Thr394Thr, in the PGC-1alpha gene have any impacts on interaction with myocyte enhancer factor (MEF) 2C.</p><p><b>METHODS</b>The SNPs in all exons of the PGC-1alpha gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and direct sequencing. Thereafter, 263 type 2 diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1alpha gene alter the interaction with MEF2C.</p><p><b>RESULTS</b>Three frequent SNPs (Thr394Thr, Gly482Ser and Thr528Thr) were found in exons of the PGC-1alpha gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls (40.1% vs 29.3%, P < 0.01). Even in controls, the 482Ser (A) carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly (G) carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr (A) had a synergic effect on the interaction between 482Ser variant and MEF2C.</p><p><b>CONCLUSIONS</b>The results suggested that the 482Ser variant of PGC-1alpha conferred the susceptibility to type 2 diabetes in the southern Chinese population. The underlying mechanism may be attributable, at least in part, to the altered interaction between the different variants (Gly482Ser, Thr394Thr) in the PGC-1alpha gene and MEF2C.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Asian People , Genetics , China , Diabetes Mellitus, Type 2 , Ethnology , Genetics , Genotype , Heat-Shock Proteins , Genetics , Metabolism , MEF2 Transcription Factors , Myogenic Regulatory Factors , Metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Polymorphism, Single-Stranded Conformational , Protein Binding , Transcription Factors , Genetics , MetabolismABSTRACT
Objective To reinvestigate the value of overnight low-dose dexamethasone suppression test in the diagnosis of Cushing syndrome.Methods Fifty-two patients with Cushing syndrome and 153 patients with simple obesity or essential hypertension in whom Cushing syndrome was excluded were studied retrospectively in order to compare the sensitivity and specificity of different serum cortisol cut-off levels in overnight 1 mg dexamethasone suppression test in the diagnosis of Cushing syndrome.Results The sensitivity of 50% of basal serum cortisol level at 8:00 and of the serum cortisol cut-off levels of 275,200,138,50 nmoL/L at 8:00 after the overnight 1 mg dexamethasone suppression test was 92.3%,92.3%,92.3%,92.3% and 100.0% respectively, and the specificity was 90.8%,98.7%,96.1%,91.5% and 78.4%,respectively.Conclusion The serum cortisol cut-off level of 50 nmol/L in the overnight 1 mg dexamethasone suppression test has very high sensitivity and can be used as a screening test for Cushing syndrome.
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Plasma aldosterene/renin ratio (ARR) is a sensitive screening test and parameter for primary aldosteronism(PA).The use of ARR leads to a marked increase in the detection rate of PA in the hypertensive population.However,ARR remains a nonstandardized test,and the cutoff value of ARR used in the different studies is varied.Further and systematical studies are needed to improve the accuracy of the test.
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Objective To induce mouse embryonic stem(ES)cells to differentiate into insulin-secreting cells by means of a 5-step model system.Methods E14.1 mouse ES cells were cultured in the presence of leukemia inhibitory factor(LIF)for 2 days(step 1),then the cells were cultured in hanging drops to form embryonic bodies(EBs)and the resulting EBs were cultured in suspension for 6 days in the presence of basic fibroblast growth factor bFGF(step 2).Subsequently the EBs were cultured in the medium containing glucagon- like peptide 1(GLP-1),hepatocyte growth factor(HGF),nerve growth factor(NGF)and nicotinamide for 10 days(step 3).After that,the EBs were dissociated into single cells,and the cells were cultured in monolayer in the presence of GLP-1,betacellulin,activin A,bFGF and nicotinamide for 10 days(step 4).Finally,the cells were cultured in low-glucose medium containing nicotinamide for 4 days(step 5).Insulin and some other islet- related genes expressions were investigated using RT-PCR and insulin expression was also investigated by DTZ- staining and immunohistochemistry.The percentage of insulin-secreting cells was evaluated by flowcytometry and insulin concentrations were measured by RIA.Results mRNA expression of insulin became visible at step 3 and more evident at step 5.Additionally,at step 5,mRNAs of glucagon,somatostatin,pancreatic polypeptide(PP), pancreatic duodenal homeobox 1(PDX-1),beta-cell E box transactivator 2(Beta2)and neurogenin 3(Ngn3) were detected.DTZ-staining positive cells and insulin immunohistochemical staining positive cells were observed. The percentage of insulin-positive cells was(24.0?2.5)%(n=6).In the presence of 5.6 mmol/L and 25 mmol/L glucose,insulin concentrations were(0.05?0.01)?g/L and(0.13?0.02)?g/L respectively(n= 6).Conclusion E14.1 mouse ES cells can be induced to differentiate into insulin-secreting cells by the 5-step model system.Insulin-secreting cells can release insulin into culture medium when treated with glucose,and insulin concentrations increase with rising concentration of glucose.