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R M Tacchino

Publications and source records attributed to R M Tacchino.

13 recordsLinked to original sources
PubMed1994

Glucose-induced thermogenesis in postobese women who have undergone biliopancreatic diversion.

We evaluated the metabolic response to a standard (75-g) oral-glucose-tolerance test (OGTT) in eight post-obese women (PO) who underwent biliopancreatic diversion and in eight healthy control women (C). All subjects had been weight-stable for > or = 2 y. Blood samples for glucose, insulin, C-peptide, and nonesterified free fatty acids were taken at baseline and during 180 min after the glucose load. Plasma glucose and insulin concentrations at baseline and during the OGTT were similar in the two groups, suggesting the absence of an insulin-resistant state in the PO. Continuous indirect calorimetry was performed throughout the test. Glucose-induced thermogenesis (GIT) was higher in PO than in C (8.6 +/- 2.6 vs 4.3 +/- 1.9%; P < 0.01). These data indicate that GIT and insulin-glucose metabolism are not impaired in postobese patients when a near ideal body weight is reached and maintained after weight loss; this suggests that thermogenic deficiencies and hyperinsulinemia-insulin resistance are alterations secondary to obesity.

Adult↗
PubMed1993

Turnover and oxidation rates of plasma-free fatty acids in obese patients treated with dexfenfluramine.

In order to assess a possible direct metabolic effect of dexfenfluramine (dF) apart from its action on food intake reduction, 10 obese postmenopausal women and 10 obese men (BMI = 32.19 +/- 1.99 kg/m2) were studied in a single-blind fashion: 4 weeks on placebo (D-28 to D0) and 4 weeks on dF (D0 to D28). A balanced diet, computed on the basis of basal metabolic rate x 1.4, was followed throughout the study. The patients' alimentary diary was checked for compliance. FFA turnover and oxidation rate, using 1-14C palmitate intravenous infusion, was determined basally (D0), after single high-dose (30 mg, D1) and after long-term (15 mg b.i.d., D28) administration. Indirect calorimetric measurements were performed using a mass spectrometer, and the usual metabolic parameters were computed. The isotope method was used in order to assess plasma FFA oxidation rate. Plasma FFA were analyzed by high-performance liquid chromatography (HPLC) and specific activity was determined at 55, 60, 65 and 70 min by counting dpm in HPLC eluates corresponding to the retention time of palmitate. The turnover rate was not significantly modified after single high-dose dF administration when compared to basal values (6.24 +/- 1.62 at D1 vs. 5.63 +/- 2.07 mmol/kg/min at D0), but was significantly increased at D28 compared with D0 (6.35 +/- 1.96 mmol/kg/min; p < 0.05). A significant increase in FFA oxidation rate was observed with respect to basal values after dF administration both at D1 (0.81 +/- 0.33 at D1 vs. 0.61 +/- 0.21 mmol/kg/min at D0; p < 0.01) and at D28 (0.77 +/- 0.34 mmol/kg/min; p < 0.015).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Metabolic effects and disposition of sebacate, an alternate dicarboxylic fuel substrate.

Disodium sebacate is a 10-carbon-atom dicarboxylic acid, proposed as substrate for parenteral nutrition. We investigated its pharmacokinetic profile and thermogenic effect during a short-time infusion (5 h at 10 g/h) in 7 male volunteers. Sebacate in serum and urine was measured by high-performance liquid chromatography. A single-compartment model with two linear elimination routes was fitted. Metabolic measurements (VO2, VCO2, respiratory quotient, metabolic rate) were continuously performed for 8 h (5 h during and 3 h after the infusion) by a canopy indirect calorimeter. The apparent volume of distribution of sebacate was 8.39 +/- 0.69 liters, and the plasma fractional removal rate constant was 0.0086 +/- 0.00077 min-1. The average half-life and plasma clearance were 80.6 min and 72 ml/min, respectively. The increase in metabolic rate, the decrease in respiratory quotient and the changes in ketone body, glucagon and insulin levels during the infusion were not significant. 24-hour catecholamine excretion was within normal limits. Calories administered by sebacate seem to be available for utilization without relevant metabolic side effects.

Adult↗
PubMed1990

Probability and the patient state space.

This paper describes work to develop a model-based system to support clinical decision-making. In previous articles, we have developed (from 695 measurement sets obtained from 148 patients) a physiologic state classification based on a set of 11 cardiovascular and metabolic measurements. There is an R or reference state, for stable ICU patients. Patients under (operative, traumatic, or compensated septic) stress, or with (septic or hepatic) metabolic, respiratory, or cardiac insufficiency are in the A, B, C, or D states, respectively. We wished to make the state easier to measure and eventually available continuously, automatically, and noninvasively, as well as reflecting a wider group of bodily systems. The 5 centers define a 4 dimensional affine subspace, designated the cardiovascular state space. Using eigenvector analysis, we have found four new derived physiologic variables CV1, CV2, CV3, and CV4 that span the state space. We have fit sets of linear regression equations that allow the patient's position in the state space, and therefore his state, to be determined from more easily obtainable sets of measurements. Further, we selected 1966 measurement sets from 512 patients at two hospitals. We used the data from 250 of these patients to define 13 prototypical types, namely survivors and deaths from various combinations of sepsis, cardiogenic decompensation, cirrhosis, and pneumonitis, following trauma or general surgery. For any future patient, the statistical theory of Bayesian inference allows one to infer back from the measurements observed to the probability of his being of any of these types and of surviving or dying. We used this method to predict the outcome of the other 262 patients, prospectively. Statistically, the predictions of survival or death were not significantly different from the actual. For individual patients, the method predicts a clinical course that closely follows the actual episodes in their history. These results confirm and explain the validity of the concept of the patient state and make the state easier to compute. The patient state and the probability plot together help to stage, select, and evaluate therapy. They do not replace the clinician's judgement, but rather are tools that help the clinician to exercise judgement.

Adult↗
PubMedDate not supplied

Preliminary studies of a dicarboxylic acid as an energy substrate in man.

Azelaic acid (Az), a straight saturated chain nine carbon dicarboxylic acid, was administered in saline form to six healthy male volunteers by iv route. Serum levels of Az and urinary amounts of both azelaic and pimelic (C7) acids were measured by an improved gas liquid chromatographic method. Stoichiometric analysis of Az metabolism was compared with that of glucose and palmitic acid. The respiratory quotient (RQ) as well as the ATP/CO2 ratio of Az were quite similar to that of palmitic acid. Therefore, Az oxidation is associated with a low cost of ATP synthesis in terms of carbon dioxide production. At the infusion rate used (7.5 g/hr) more than 50% of the administered dose was excreted in the urine. However, the remaining portion was cleared from the plasma in 200 min suggesting an uptake by body tissues which was also confirmed by indirect calorimetric analysis.

Adenosine Triphosphate↗
PubMedDate not supplied

Short-term infusion of azelaic acid vs intralipid in healthy subjects evaluated by indirect calorimetry.

Medium-chain dicarboxylic acids (MCDA) are usually considered byproducts of beta-oxidation when omega-oxidizable medium-chain monocarboxylic acids are accumulated, as in beta-oxidation impairment. However, evidence exists of a mitochondrial and cytoplasmatic peroxisomal carnitine independent beta-oxidation of these diacids. Our purpose was to evaluate whether MCDA could be used as source of calories. The metabolic response to intravenous administration of azelaic acid (AA) vs Intralipid (IL) was evaluated in six healthy overnight fasting male volunteers who received an infusion of 10 g of AA over 80 min and as a control 10 g of IL. AA reached a peak concentration at 80 min, (589 +/- 61 micrograms/ml) and was rapidly cleared from plasma (82 +/- 5 micrograms/ml at 240 min). Respiratory and metabolic parameters were evaluated by indirect calorimetry from the beginning of the infusion for 240 min. In both groups the CO2 production (VCO2) remained unchanged with no significant change from basal values. The O2 consumption (VO2 ml/min/m2) increased over basal values reaching a peak at the end of the infusion in both groups (AA from 119.4 +/- 16.9 to 143.0 +/- 27.6; IL from 124.7 +/- 16.8 to 152.3 +/- 29.5). Respiratory quotient (RQ) consequently decreased significantly (AA from 0.85 +/- 0.06 to 0.76 +/- 0.06; IL from 0.89 +/- 0.06 to 0.78 +/- 0.03) and calories derived from lipids increased. Metabolic rate (MR kcal/hr/m2) showed a slight increase (AA from 34.0 +/- 4.4 to 40.3 +/- 6.8; IL from 35.9 +/- 5.1 to 41.3 +/- 10.5). There was no significant difference between AA and IL treatment in all measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Tissue uptake and oxidation of disodium sebacate in man.

In order to better ascertain its possible use as an alternative fuel substrate in total parenteral nutrition, sebacate (Sb) metabolism was studied in seven overnight-fasting healthy male volunteers, who received a constant iv infusion (99 mmoles over 8 hours) of disodium sebacate. Sb oxidation rate was determined using an isotopic sebacate (disodic salt of (1-10)14C-sebacic acid) infusion (100 mu Ci from the fourth to the eighth hour of the cold sebacate infusion). Blood samples were collected during and after sebacate infusion at intervals of 30 minutes and Sb serum concentrations were determined by high performance liquid chromatography. Excreted radioactivity (mu Ci/min) was measured by bubbling the expired air into an apparatus containing 3 mEq hyamine to trap CO2 from a 20-L Douglas-bag. CO2 production and O2 consumption were measured before and at 4 and 8 hours after starting the infusion. Twenty-four hour nitrogen excretion with urine was obtained. The RQ and the percent of calories derived from lipid oxidation were calculated by indirect calorimetry. The Sb serum level at the plateau phase was (mean +/- SD) 4.54 +/- 0.71 mumole/mL, the overall rate of tissue uptake was 180.89 +/- 4.50 mumole/min, and the percent oxidation was 6.14 +/- 0.44%. At the end of Sb infusion the RQ dropped to 0.839 +/- 0.043, the percent of calories due to sebacate oxidation was 1.59 +/- 0.52%, and the calories derived from lipids increased to 37.77 +/- 12.90%. These data show that a definite amount of the sebacate infused is oxidized in human tissues.

Adipates↗
PubMedDate not supplied

Use of even-numbered carbon atom dicarboxylic salts in parenteral nutrition as fuel substrate.

Sebacic acid (C10), a saturated, straight-chain dicarboxylic acid with 10 carbon atoms in disodic salt form, was given intravenously to two groups of healthy male volunteers in order to evaluate its possible use in total parenteral nutrition. The first group, composed of six subjects, received 1000 mg of sebacate as a bolus; six other subjects (second group) received 10 g of sebacate dissolved in 500 mL of double-distilled water at an infusion rate of 3.33 g/h over 3 hours. The serum sebacate data for each subject were analyzed by computer, using biexponential fit corresponding to a 2-compartment open model. The distribution half-life (t1/2) was 0.34 +/- 0.06 hour and the elimination phase was rather rapid (Ke = 2.10 +/- 0.38/h); the volume of the central compartment was 2.79 +/- 0.54 L and the volume of tissue compartment 3.72 +/- 0.14 L. These data showed a good tissue fixation of sebacate. The plasma clearance was evaluated to be 5.96 +/- 2.19 L/h and the renal clearance was 19.22 +/- 10.69 L/h, indicating that a tubular secretion of C10 takes place. The serum concentration of sebacate raised to the maximal value at the end of the infusion (180 minutes), corresponded to 480.50 +/- 43.02 micrograms/mL. Respiratory and metabolic parameters were evaluated by indirect calorimetry from the beginning of the infusion for 210 minutes. The O2 consumption (VO2 mL/min per square meter) remained essentially unchanged throughout the experiment (from 154.3 +/- 28.3 at 0 to 155.3 +/- 39.5 at time 180 minutes).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗