Biomedical subjects

G Sergi

Publications and source records attributed to G Sergi.

26 records · Page 2Linked to original sources

PubMed1990

Insulin regulation of glucose and lipid metabolism in massive obesity.

Eight obese patients and 12 normal individuals underwent a euglycaemic insulin clamp (20 and 40 mU m2-1.min-1) along with continuous infusion of 3-3H-glucose and 1-14C-palmitate and indirect calorimetry. Basal plasma glucose concentration (4.7 +/- 0.3 vs 4.4 +/- 0.2 mmol/l) was similar in the two groups, whereas hepatic glucose production was slightly higher in obese individuals (1.11 +/- 0.06 vs 0.84 +/- 0.05 mmol/min) in spite of higher plasma insulin levels (17 +/- 2 vs 6 +/- 1 mU/l; p less than 0.01). Insulin inhibition of hepatic glucose production was impaired in obese subjects. Glucose disposal by lean body mass was markedly reduced both at baseline (11.7 +/- 1.1 vs 15.6 +/- 0.6 mumol.kg-1.min-1; p less than 0.05) and during clamp (15.0 +/- 1.1 vs 34.4 +/- 2.8 and 26.7 +/- 3.9 vs 62.2 +/- 2.8 mumol.kg-1.min-1; p less than 0.01) Oxidative (12.2 +/- 1.1 vs 17.8 +/- 1 and 16.1 +/- 1.1 vs 51.1 +/- 1.7 mumol.kg-1.min-1; p less than 0.05-0.002) and non-oxidative glucose metabolism (3.9 +/- 1.1 vs 15.0 +/- 2.8 and 12.8 +/- 3.3 vs 38.2 +/- 2.2 mumol.kg-1.min-1; p less than 0.01-0.001) were impaired. Basal plasma concentrations of non-esterified fatty acids (635 +/- 75 vs 510 +/- 71 mumol/l) and blood glycerol (129 +/- 17 vs 56 +/- 5 mumol/l; p less than 0.01) were increased in obese patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Metabolic and hormonal effects of early nutritional supplementation after surgery in burn patients.

We evaluated, in burn patients, the metabolic and hormonal effects of early nutritional supplementation after a severe stress event represented by the deep surgical excision of the burn wounds and autograft coverage. The surgical procedure induced a 50% increase from baseline value of the resting metabolic rate. Immediate nutritional supplementation avoids the adaptive stress-related increments of urinary catecholamine excretion and glucagon secretion while insulin secretion is maintained. The urinary cortisol excretion, significantly increased after surgery in study and control groups, was unaffected by the nutritional intervention. The favorable insulin/glucagon ratio and the control of catecholamine response in early nutritionally supplemented patients are associated with the maintenance of a positive N balance in the days after surgery.

Adult↗

PubMed1988

Visceral obesity and diabetes.

The cross-sectional subcutaneous and visceral areas of adipose tissue, measured on computed tomographic scans at abdominal level and the subcutaneous/visceral fat area ratio (S/V ratio) distribution have been calculated in 155 subjects. Using the S/V ratio as discriminator, two groups of patients of both sexes, with subcutaneous or visceral type of obesity have been selected. Metabolic studies demonstrate a significant reduction of glucose tolerance at the oral glucose load and a significant increase of the insulin response in patients with visceral obesity. The size of the omental fat cells was larger in visceral obesity, while the size of subcutaneous fat cells was larger in subcutaneous obesity. A significant correlation was found between the S/V area ratios and the subcutaneous/visceral fat cell weight ratios. In vitro studies on subcutaneous and omental fat obtained during surgery from 9 patients with subcutaneous obesity and 7 patients with visceral obesity demonstrate a significantly higher isoprenaline-stimulated lipolytic response in omental fat of patients with visceral obesity. The lipoprotein lipase activity in subcutaneous fat was higher than in omental fat in both types of obesity.

Adipose Tissue↗

PubMedDate not supplied

Assessment of body composition in elderly: accuracy of bioelectrical impedance analysis.

BACKGROUND: In the literature there are several body impedance analysis (BIA) prediction equations generally determined in younger populations and their accuracy in the elderly has not been adequately confirmed. OBJECTIVE: We verified the reliability of the BIA method in a body composition study in the elderly. METHODS: To assess the accuracy of bioelectrical impedance analysis we compared this method with dual photon absorptiometry (DPA), assumed as a gold standard; body composition was predicted by seven BIA prediction equations in 24 healthy elderly individuals. RESULTS: The best equation in fat-free mass (FFM) estimation is the RJL System formula (published by Segal in 1988); nevertheless, the wide range of the error in FFM estimating may limit its clinical application. The FFM hydration variability seems to be the principal variable which explains the error in FFM estimation by BIA prediction equations. CONCLUSION: These findings indicate that the use of BIA equations is not interchangeable, when FFM is calculated in an elderly population, and more validation studies are necessary in this age group to evaluate the clinical application of this method.

Absorptiometry, Photon↗

PubMedDate not supplied

Heart rate and metabolic response to burn injury in humans.

BACKGROUND: Although frequently done, estimating the energy requirements of individual burn patients without measuring their resting metabolic rate is a less than satisfactory method of evaluation. METHODS: We tested whether heart rate, which relates to the energy expenditure during physical activity, is also associated with postburn hypermetabolism (calculated as percentage increase of resting metabolic rate above the predicted normal fasting resting metabolic rate). Twenty-three patients [12 men and 11 women, aged 38 +/- 13 years (mean +/- SD); weight, 71.6 +/- 14.8 kg; body mass index, 25.4 +/- 3.6; total burn surface area, 35.3 +/- 17.8% (percentage of body surface)] were studied weekly for 3 weeks after an overnight fast. RESULTS: Measured resting metabolic rates and heart rates were 2016 +/- 497 kcal/d, 101 +/- 13 bpm (n = 19); 2231 +/- 485 kcal/d, 107 +/- 13 bpm (n = 18); and 1903 +/- 598 kcal/d, 99 +/- 14 bpm (n = 11) for weeks 1, 2, and 3, respectively. Postburn hypermetabolism was +36% +/- 19%, +55% +/- 27%, and +36% +/- 35% in the first, second, and third week, respectively. In each week postburn hypermetabolism correlated with heart rate (r = 0.65, p = .003; r = 0.69, p = .001; and r = 0.80, p = .002, respectively). Only in the second week did postburn hypermetabolism correlate with total burn surface area (r = 0.52, p = .02); there was no correlation with body temperature. In a multiple regression analysis, predicted resting metabolic rate, heart rate, and total burn surface area together explained 77% of all of the variance observed in the 48 fasting resting metabolic rates that were measured in the study (r2 = 0.77, p < .0001), and each of these variables also had a significant partial correlation with fasting resting metabolic rates (r2 = 0.45, p < .0001; r2 = 0.29, p < .0001; and r2 = 0.03, p < .03, respectively). CONCLUSIONS: In burn patients, variability in heart rate is associated with a significant part of postburn hypermetabolism variability. Therefore, heart rate may be considered a useful variable to be used for the evaluation of the energy requirements of severely burned patients.

Adolescent↗

PubMedDate not supplied

[Waist to hip ratio and the distribution of adipose tissue].

The aim of the study was to assess the relation between the waist to hips ratio (WHR) and the distribution of adipose tissue in visceral or subcutaneous site through the use of CAT. Results are expressed as the ratio of visceral to subcutaneous adipose tissue area (VSR). A total of 61 patients were randomly selected for inclusion in the study. Contrary to normal weight subjects, obese patients did not reveal significant correlations between the two ratios. Following multi-variant analysis in normal weight subjects, WHR appeared to be influenced by sex, BMI and VSR. In patients with prevalently visceral adiposity WHR was determined by sex and VSR, whereas in patients with prevalently subcutaneous adiposity it was influenced by BMI alone. In conclusion, the significant correlations between WHR and tomographic indices of adipose tissue distribution reported in the literature are not present in all types of patient, and in particular are not found in obese patients and normal weight subjects with prevalently subcutaneous adiposity.

Abdomen↗

PubMedDate not supplied

[Vertical gastroplasty. Evaluation of efficacy].

The paper evaluates the results of vertical gastroplasty in the treatment of morbid obesity. A series of 34 patients (24 F and 10 M) with the following characteristics was included in the study: mean age 41 years, preoperative weight 141 kg, % of ideal weight 204%, BMI 49; mean follow-up was 35 months. Postoperative mortality was zero and there were reduced early and long-term complications. Mean weight loss, expressed as a percentage of overweight, at 6 months was 48.5%, 56.8% at 12 months, 63.4% at 24 months and 67.2% at 36 months. The authors conclude that, given the low incidence of complications and the satisfactory weight loss which was maintained long after the operation, vertical gastroplasty appears to be the preferred operation, since it represents a safe and effective method of treating pathological obesity.

Adult↗

PubMedDate not supplied

[Arrhythmia in thalassemia major: evaluation of iron chelating therapy by dynamic ECG].

Arrhythmias and sudden death represent striking features in the natural history of thalassemia major. Antiarrhythmic treatment, however, does not appear to change the clinical course. During recent years the disease's therapeutics approach has undergone a substantial evolution, being more adequate the transfusional regimens as well as more effective the iron chelation therapy through subcutaneous infusion of deferoxamine. The aim of the present study was to determine possible influences exerted by the current treatment upon disease's arrhythmic disorders. Thirty patients of both sexes were enrolled in the study. The age ranged from 9 to 24 years. No congenital or acquired heart diseases were present. Each patient underwent concentrated red cell transfusions (in order to obtain pretransfusional hemoglobin levels of 10-11 g%), and iron-binding therapy through continuous subcutaneous microinjection of deferoxamine 40-50 mg/kg/day (6-8 hours/day, 6 days/week). Patients were divided in 2 groups: the first group (group A) comprising the 16 patients with good therapeutic compliance and regular pharmacological regimen; the second group (Group B) including the remaining poorly compliant 14 patients. The following parameters were analyzed: age, average hemoglobin levels during the last year, total amount of red cell transfusions, ferritin levels, starting age of iron-binding therapy. Moreover, each patient underwent 24-hour ECG Holter monitoring. Age (Group A: 18 +/- 4.6; Group B: 14 +/- 2.7; p < 0.02), total amount of transfusions (Group A: 272 +/- 73; Group B: 211 +/- 44; p < 0.03), and ferritin levels (Group A: 1697 +/- 860; Group B: 2908 +/- 730; p < 0.002) proved to be significantly different in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗