Biomedical subjects

Elena Ryder

Publications and source records attributed to Elena Ryder.

5 recordsLinked to original sources

PubMed2003

Presence of impaired insulin secretion and insulin resistance in normoglycemic male subjects with family history of type 2 diabetes.

In order to demonstrate the effect of family history (FH) coexisting with obesity in insulin resistance (IR) and secretion in subjects at risk for type 2 diabetes, fasting and 2 h post-glucose load serum glucose and insulin concentrations were measured in 143 individuals, 66 men and 77 women, ages ranging from 18 to 68 years, who were considered at risk but were normoglycemic following ADA criteria. Insulin resistance was estimated using HOMA(IR), basal hyperinsulinemia and I(0)/G(0) ratio. Insulin secretion was estimated by means of HOMA(beta-cell), DeltaI(30-0)/DeltaG(30-0) ratio and the insulin concentration at 30 min post-glucose load (I(30)). Disposition index (DI) was calculated to verify if insulin secretion compensate IR. Obesity in males produced an increase in all the parameters indicative of IR in both groups of individuals, with (FH(+)) or without (FH(-)) family history of diabetes, increase that was more pronounced in those FH(-). This effect was not observed in women. The parameters indicative of insulin secretion showed that only in males the presence of FH(+) was responsible for a significant decrease in insulin secretion, mainly expressed as lower values of HOMA(beta-cell) in obese as well as in non-obese. The I(30) and the ratio DeltaI(30-0)/DeltaG(30-0), although lower, did not reach statistical significance. The DI showed that only when obesity and FH were associated the decrease in insulin secretion was not a compensatory response to the IR present in those individuals. In conclusion, normoglycemic obese and non-obese male subjects of Hispanic (Latinos) origin with a family history of type 2 diabetes present not only IR but impaired insulin secretion, having the obese FH(+) and additional risk like low DI.

Adolescent↗

PubMed2003

[Metabolic programming].

The normal programmed development of a multicellular organism lays on a synchronized series of events driven by genetic instructions acquired during conception. During the early critical periods in life the organism has the ability to respond to environmental situations that are strange to normal development by adaptations at several levels. Such early adaptations change the organism's physiology and metabolism and continue to be expressed even in the absence of the stimulus that initiated them, a process called "metabolic programming". Human epidemiological and animal studies support the concept that metabolic programming induced by nutritional experiences during critical periods in development might have consequences later in adulthood. Moreover, it has been suggested that those nutritional experiences in children during the perinatal period could contribute to metabolic programming leading to diseases of appearance during the adult life such as obesity and diabetes.

Adult↗

PubMed2003

[Prevalence of obesity and hyperinsulinemia: its association with serum lipid and lipoprotein concentrations in healthy individuals from Maracaibo, Venezuela].

The aim of this study was to analyse the prevalence of obesity and hyperinsulinemia and their association with lipid profile alterations on apparently healthy individuals from Maracaibo, Venezuela. We evaluated 306 men and 41 women, ages ranging from 33 to 65 years. All subjects underwent cardiovascular evaluation and laboratory examination after 10-12 h fasting, for glycaemia, total cholesterol, TG, VLDL-C, LDL-C and HDL-C as well as insulin. Seventy-four percent of men and 56.1% of women showed obesity (BMI > 25 Kg/m2). Men showed high concentrations of TG (48.3%), total cholesterol (40.2%), VLDL-C (48.3%) and LDL-C (33.9%) and low HDL-C levels (48%). The most frequent alteration on the lipid profile in women was high total cholesterol (46%) and LDL-C (51.2%). Men had significantly higher insulin concentrations than women (p < 0.005). After they were classified as obese or non obese, the obese subjects (men and women) showed higher prevalence of lipid profile alterations and insulin concentrations than non obese. The insulin concentration in obese men correlated with BMI, TG, VLDL-C and HDL and, in women with BMI, TG and VLDL-C. In conclusion, a high percentage of men and women in this study showed obesity and this obesity, specially in men, was strongly associated with lipid profile alterations and high insulin concentrations both well known cardiovascular risk factors.

Adult↗

PubMed2003

[Hemostatic coronary risk factors in a healthy population of Maracaibo, Venezuela].

The purpose of the present work was to determine the plasma concentrations of fibrinogen and Von Willebrand Factor (VWF) as well as platelet aggregation, in an apparently healthy population of 306 men and 41 women, 33 to 65 years of age, workers of the national oil industry (PDVSA, Maracaibo), as a base investigation in a 5-year prospective national collaborative study. The participants were previously subjected to a thorough clinical examination with cardiovascular evaluation and laboratory tests. Clottable fibrinogen and VWF concentrations were determined in platelet poor plasma, the last one by immunoclectrophoresis, and a multimeric analysis of VWF was performed on those plasmas with concentrations higher than 150 U/dL by SDS agarose electrophoresis, followed by cellulose membrane transference. Platelet aggregation was studied in platelet rich plasma with no addition of stimulants and after collagen and ristocetin were added. Forty per cent of men and 65.8% of women, showed fibrinogen concentrations above 300 mg/dL (p < 0.01) and 12.2% of men and 15.4% of women had VWF values higher than 150 U/dL, with normal multimeric distribution. Fourteen individuals presented spontancous platelet aggregation and increased aggregation in 12 and 13 of them, after induction with collagen and ristocetin respectively. Comparing these findings with those of previous collaborative studies from other countries, the present results could mean that an important proportion of the population here studied, could be at risk for a future coronary event; however, as these are the base findings in Maracaibo, the significance of our results will be better evaluated at the end of the five year study.

Adult↗

PubMed2003

Lean adolescents with increased risk for metabolic syndrome.

The aim of the present study was to determine in adolescents the relationship between insulin levels and body mass index (BMI), body fat distribution, diet, life style and lipid profile. We studied 167 adolescents (68 boys and 99 girls) whose ages ranged from 14 to 17 years. A detailed medical (including pubertal stage) and nutritional record was obtained from each subject. Biochemical measurements included fasting serum insulin, glucose, total cholesterol (TC), triglycerides (Tg), HDL-C, LDL-C and VLDL-C. HOMA insulin resistance (IR) and HOMA beta-cell function (beta-cell) were calculated. Insulin levels were over 84 pmol/L (cut off normal value in our lab) in 56% of the boys and 43% of the girls. Thirty-seven percent of lean adolescents whose BMI was 21.5 +/- 1.9 kg/m2 presented higher fasting insulin levels. HOMA IR, Tg, systolic (SBP) and diastolic blood pressure (DBP) values when compared to a lean normoinsulinemic group. Insulin levels were correlated (p < 0.01) with body mass index. Both boys and girls in the highest BMI quartile (BMI > 24 kg/m2) had significantly higher serum insulin, HOMA beta-cell, and Tg levels, and the lowest HDL-C levels. A high-energy intake rich in saturated fat and low physical activity were found in this lean but metabolically altered adolescents. We conclude that even with a BMI as low as 21 kg/m2 an inappropriate diet and low physical activity might be responsible for the high insulin levels and dislipidemias in adolescents.

Adolescent↗