Serum leptin in subjects with impaired glucose tolerance in relation to insulin sensitivity and first-phase insulin response.

Objective: It has been suggested that insulin could regulate the secretion of leptin, the ob gene product, but the findings have been contradictory. Therefore, we studied the association between leptin and insulin secretion and insulin sensitivity in impaired glucose tolerance (IGT).

Subjects: 39 obese subjects (17 men, 22 women, body mass index (BMI) 30.

Increased expression of telomerase RNA component is associated with increased cell proliferation in human astrocytomas.

Deregulation of telomerase, a ribonucleoprotein polymerase that compensates progressive loss of telomeric (TTAGGG)n repeats during DNA replication, has been suggested to facilitate tumorigenesis and cellular immortality by providing unlimited proliferation capacity for cancer cells. We investigated the relationship between tumor proliferation activity and in situ expression of the telomerase RNA component in 46 human grade I to IV astrocytomas. Heterogeneously distributed telomerase RNA expression was detected from all of the tumor samples as well as from normal human brain tissue.

Periprosthetic bone loss and regional bone turnover in uncemented total hip arthroplasty: a prospective study using high resolution single photon emission tomography and dual-energy X-ray absorptiometry.

Single photon emission computed tomography (SPECT) at 6 and 12 months and dual-energy X-ray absorptiometry (DXA) at 0, 6, and 12 months were performed prospectively in 15 patients who had undergone uncemented total hip arthroplasty (THA) without any complications. Periprosthetic bone mineral density (BMD) decreased significantly in all regions of interests (ROIs) during 1 year of follow-up. The greatest annual decrease was found in the lesser trochanter region (22.

Mild myocardial infarction--a classification problem in epidemiologic studies. WHO MONICA Project.

In studies assessing the trends in coronary events, such as the World Health Organization (WHO) MONICA Project (multinational MONItoring of trends and determinants of CArdiovascular disease), the main emphasis has been on coronary deaths and non-fatal definite myocardial infarctions (MI). It is, however, possible that the proportion of milder MIs may be increasing because of improvements in treatment and reductions in levels of risk factors. We used the MI register data of the WHO MONICA Project to investigate several definitions for mild non-fatal MIs that would be applicable in various settings and could be used to assess trends in milder coronary events.

Are risk factors for conversion to NIDDM similar in high and low risk populations?

Mexican Americans have an increased risk of non-insulin-dependent diabetes mellitus (NIDDM) relative to non-Hispanic whites which is only partially explained by their excess overall obesity and unfavourable body fat distribution. Non-diabetic Mexican Americans have hyperinsulinaemia and insulin resistance relative to non-Hispanic whites. We therefore hypothesized that the insulin resistance might be a more important predictor of NIDDM in high-risk populations characterized by obesity and insulin resistance, while compromised insulin secretion might be a more important risk factor for NIDDM in low-risk populations.

Apolipoprotein A-IFin. Dominantly inherited hypoalphalipoproteinemia due to a single base substitution in the apolipoprotein A-I gene.

We have identified a large kindred with severe serum HDL cholesterol deficiency. The proband, a 65-year-old woman, had greatly diminished concentrations of serum HDL cholesterol (0.19 mmol/L) and apolipoprotein (apo) A-I (21.

Polymorphisms of the genes encoding apoproteins A-I, B, C-III, and E and LDL receptor, and cholesterol and LDL metabolism during increased cholesterol intake. Common alleles of the apoprotein E gene show the greatest regulatory impact.

Genetic and dietary factors regulate serum cholesterol level, but detailed investigations into their interactions have not been established. We assessed the effects of apoprotein (apo) E phenotype and polymorphic alleles of the apo A-I, apo B, apo C-III, and LDL receptor genes, separately and together, on regulation of serum LDL cholesterol level. The study group consisted of 29 middle-aged men, and cholesterol absorption, bile acid, and cholesterol synthesis and LDL apo B kinetics were studied in these men during low- and high-cholesterol diets.

Delayed postprandial retinyl palmitate and squalene removal in a patient heterozygous for apolipoprotein A-IFIN mutation (Leu 159-->Arg) and low HDL cholesterol level without coronary artery disease.

A low HDL cholesterol level is frequently but not consistently associated with inefficient postprandial fat clearance. We studied triglycerides, retinyl palmitate and squalene and apolipoprotein B-48 after a fat loading test in one subject heterozygous for a novel point mutation of apolipoprotein A-I (A-IFIN, Leu 159-->Arg) and low HDL cholesterol level without coronary artery disease, and in 16 healthy controls with the same apolipoprotein E phenotype, 3/3, as the proband. HDL cholesterol and apolipoprotein A-I levels were 0.

Decline of coronary heart disease mortality in Finland during 1983 to 1992: roles of incidence, recurrence, and case-fatality. The FINMONICA MI Register Study.

Background: The rate of coronary heart disease (CHD) mortality in eastern Finland has been the highest in the world. The official mortality statistics suggest, however, that is has declined by 60% during the past 20 years. The aim of the present study was to examine the contributions of incidence, recurrence, and case fatality of coronary events to the trends in CHD mortality in three areas of Finland.

Retinopathy predicts coronary heart disease events in NIDDM patients.

Objective: Proliferative retinopathy has been shown to be associated with increased all-cause mortality in diabetic patients. We assessed the relationship between the different degrees of retinopathic changes at baseline and serious coronary heart disease (CHD) events (CHD death or nonfatal myocardial infarction) in a prospective population-based study of NIDDM patients.

Research Design And Methods: Our study is based on the 7-year follow-up cohort of 1,059 NIDDM patients in east and west Finland.

Proteinuria predicts stroke and other atherosclerotic vascular disease events in nondiabetic and non-insulin-dependent diabetic subjects.

Background And Purpose: Increased urinary albumin and protein excretion is associated with cardiovascular disease mortality independent of other cardiovascular risk factors in subjects with non-insulin-dependent diabetes mellitus (NIDDM). We assessed the relationship between the different degrees of proteinuria at baseline and the incidence of stroke, as well as other atherosclerotic vascular disease events, in a prospective study of nondiabetic and NIDDM subjects.

Methods: Our study was based on the 7-year follow-up of cohorts of nondiabetic (n = 1375) and NIDDM (n = 1056) subjects in Finland.

Carotid artery intima-media thickness in elderly patients with NIDDM and in nondiabetic subjects.

Background And Purpose: The risk of atherosclerotic vascular disease is increased both in subjects with non-insulin-dependent diabetes mellitus (NIDDM) and in those with impaired glucose tolerance compared with nondiabetic subjects. Although classic cardiovascular risk factors are operative in subjects with NIDDM, other factors closely related to insulin resistance syndrome such as diabetic dyslipidemia and hyperglycemia itself may contribute to an excessive cardiovascular disease risk in subjects with NIDDM. The purpose of this study was to investigate the carotid intimal-medial thicknesses (IMTs) and their determinants in elderly patients with NIDDM and in control subjects.

Leptin concentrations in relation to overall adiposity and regional body fat distribution in Mexican Americans.

Objective: Leptin, the product of the human OB gene is increased in obese individuals suggesting resistance to its effect. However, there is variability in leptin levels at each level of body mass index suggesting that genetic and environmental factors other than overall adiposity may regulate leptin concentrations. Moreover, the relation of leptin to various adipose depots may differ.

Decreased insulin action and insulin secretion predict the development of impaired glucose tolerance.

The relative importance of insulin resistance and abnormal insulin secretion as risk factors for the development of impaired glucose tolerance (IGT) is controversial. Few prospective data are available on metabolic precursors of IGT. We examined the relation of fasting serum insulin level (as a marker of insulin resistance) and change in insulin/glucose ratio (delta I30/ delta G30) over the first 30 min after glucose ingestion (as a marker of insulin secretion) as predictors of the 7-year development of IGT in 839 Mexican Americans and non-Hispanic whites with normal glucose tolerance at baseline from the San Antonio Heart Study.

Evaluation of periprosthetic bone using dual-energy x-ray absorptiometry: precision of the method and effect of operation on bone mineral density.

To assess the perioperative bone loss of femur during total hip arthroplasty (THA), periprosthetic bone mineral density (BMD) of the seven regions of interests (Gruen zones) was determined with dual-energy x-ray absorptiometry (DXA) preoperatively in both proximal femurs and postoperatively in the involved side in 53 patients with degenerative hip osteoarthrosis. The mean (standard deviation, SD) precision error (coefficient of variation percent, CV%) in various regions of interest (ROIs) based on two consecutive measurements (n = 16) were 2.3 (0.

A prospective analysis of the HOMA model. The Mexico City Diabetes Study.

Objective: Both insulin resistance (IR) and decreased insulin secretion have been shown to predict the development of NIDDM. However, methods to assess insulin sensitivity and secretion are complicated and expensive to apply in epidemiological studies. The homeostasis model assessment (HOMA) has been suggested as a method to assess IR and secretion from the fasting glucose and insulin concentrations.

Low levels of sex hormone-binding globulin and testosterone are associated with smaller, denser low density lipoprotein in normoglycemic men.

Recently, the phenotype with a preponderance of small, dense low density lipoprotein (LDL) has been associated with increased coronary heart disease. Although previous data indicated that decreased sex hormone-binding globulin (SHBG) and testosterone concentrations are associated with increased triglyceride and decreased high density lipoprotein (HDL) cholesterol levels in men, no data are available on the relationship of LDL composition to sex hormones. Therefore, we examined the relationship of SHBG, total and free testosterone, estradiol, and dehydroepiandrosterone sulfate to LDL size (as determined by gradient gel electrophoresis) in 87 normoglycemic men.

Metabolic precursors of hypertension. The San Antonio Heart Study.

Background: The relation of possible metabolic precursors (especially insulin resistance) to hypertension has been controversial. In addition, these associations may differ by level of obesity or ethnicity.

Methods: We followed up 1039 initially nondiabetic, nonhypertensive subjects from the San Antonio Heart Study for 7 years.

Apolipoprotein E polymorphism and LDL size in a biethnic population.

Polymorphisms in the apolipoprotein E (apoE) phenotype (especially E4) are associated with increased cardiovascular risk and particularly with increased concentrations of LDL cholesterol. Little is known, however, about whether alterations in LDL size are associated with the apoE4 phenotype. LDL size was determined by gradient gel electrophoresis, and apoE phenotype was determined by isoelectric focus in 337 nondiabetic subjects from the San Antonio Heart Study, a population-based study of diabetes and cardiovascular risk factors in Mexican Americans and non-Hispanic whites.

Site and size of rotator-cuff tear. Findings at ultrasound, double-contrast arthrography, and computed tomography arthrography with surgical correlation.

Rationale And Objectives: The authors discuss findings of ultrasound (US), double-contrast arthrography (AG), and contrast computed tomography arthrography (CTA) in assessing precise site and size of rotator-cuff tears.

Methods: Eighty-six patients were compared prospectively in a masked fashion; the results of surgery were studied in 25 patients and the results of arthroscopy were studied in 61 patients.

Results: Ultrasound detected 80% (8 of 10) of the partial-thickness tears and 90% (18 of 20) of the full-thickness tears.

Plasma oxidizability in Mexican-Americans and non-Hispanic whites.

Several lines of evidence support an atherogenic role for oxidized low-density lipoprotein (LDL). Previous studies have suggested that although Mexican-Americans have an increased rate of diabetes, obesity, elevated triglyceride levels, and low high-density lipoprotein (HDL) cholesterol levels, their rates of coronary heart disease (CHD) are similar or possibly lower than in non-Hispanic whites. Mexican-Americans have smaller, denser LDL than non-Hispanic whites.

Leptin concentrations in diabetic and nondiabetic Mexican-Americans.

Leptin, the product of the OB gene, is increased in obese individuals, suggesting resistance to its effect. We questioned whether subjects with NIDDM have an altered regulation of serum leptin levels. We used a radioimmunoassay to measure serum leptin levels in three groups from the San Antonio Heart Study: 1) 50 Mexican-Americans with NIDDM; 2) 50 nondiabetic Mexican-Americans matched by age and sex to the diabetic Mexican-Americans; and 3) 50 nondiabetic Mexican-Americans matched by age, sex, and BMI to the diabetic Mexican-Americans.

Effects of the ratio of ruminal propionate to butyrate on milk yield and blood metabolites in dairy cows.

Four Ayrshire cows (mean = 56 DIM) were used in a 4 x 4 Latin square design to study the effects of the ratio of propionate to butyrate in the rumen on milk yield, milk composition, and blood metabolites. The cows were fed a basal diet (16.2% CP, 43.

Association of Chlamydia pneumoniae and acute coronary heart disease events in non-insulin dependent diabetic and non-diabetic subjects in Finland.

Objective: It has been suggested that Chlamydia pneumoniae, a Gram-negative intracellular bacterium, is a risk factor for both myocardial infarction and chronic coronary heart disease. Previous studies have been done predominantly in non-diabetic subjects and thus the effect of diabetes on the association between C. pneumoniae antibodies and coronary heart disease has not been analysed.