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J S Marchini

Publications and source records attributed to J S Marchini.

53 records · Page 3Linked to original sources
PubMed1990

Endogenous nitrogen excretion in alcoholic patients on an enteral diet.

1. Obligatory nitrogen losses were evaluated in a group of 9 chronic alcoholic adult males of low socioeconomic status, with an intake of approximately 1 liter/day of a Brazilian beverage (45% ethanol by weight) for at least 5 years. 2. The patients were fed a nitrogen-free diet orally or by tube for 7 days. Since endogenous nitrogen excretion was statistically similar for all subjects, the data were pooled for overall analysis. 3. A stable rate of urinary nitrogen output of 28.42 +/- 11.93 mg N kg-1 day-1 was reached in about 3 days both after oral and tube feeding. The obligatory fecal losses for days 4 to 7 were 17.20 +/- 8.86 mg N kg-1 day-1. 4. Based on the factorial approach, considering the skin and other minor nitrogen losses to be 10 mg N kg-1 day-1, the total endogenous obligatory nitrogen loss for this group of alcoholic patients was 55.62 +/- 18.57 mg N kg-1 day-1. 5. The present results are discussed on the basis of the controversy about the nitrogen requirement of alcoholic patients. The endogenous nitrogen excretion demonstrated does not suggest the need for increased nitrogen intake, but the protein malnutrition of the patients points to the need for more protein.

Adult↗
PubMed1989

Zinc: an inhibitor of prolactin (PRL) secretion in humans.

The response of plasma prolactin (PRL) to oral administration of increasing doses of zinc (25.0, 37.5 and 50.0 mg) was studied in 17 normal adult men and women. Blood samples were collected at 10 and 30-min intervals over a period of 120 min after two basal times (-30 and 0 min). PRL concentrations significantly fell below basal levels in all subjects in response to the increase in plasma zinc levels, as compared to the controls. These results suggest that acute hyperzincemia can inhibit basal PRL secretion in normal individuals.

Adult↗
PubMed1988

Acute effects of human growth hormone on zinc, copper, calcium and magnesium metabolism in normal subjects.

The acute effects of human growth hormone (hGH) on the metabolism of zinc, copper, calcium and magnesium ions was studied. Seven normal subjects were perfused iv with doses of 0.2 or 1.0 mg hGH over a period of 60 min. An increase in plasma zinc, calcium and magnesium, and a decrease in plasma copper levels was noted for the 0.2 mg dose, and these effects were reversed for the 1.0 mg dose although no urine changes occurred. Plasma mobilization of these ions appears to be related to their roles as essential physiological modulators for the action of hGH.

Adolescent↗
PubMed1988

Metabolic effects of glucagon on plasma and urine zinc, copper, calcium and magnesium levels.

The present study determines the effect of glucagon on the behavior of zinc, copper, calcium and magnesium ions in human plasma and urine. Five normal adults were submitted to intravenous infusion of 2.0 mg glucagon over a period of 120 min. A decrease in plasma magnesium and copper was observed with no significant change in urine ion concentrations. We related plasma magnesium mobilization to glucagon, and copper mobilization to plasma variation in free fatty acids and albumin.

Adult↗
PubMed1988

Effect of copper on the secretion of human growth hormone.

The response of human growth hormone to the oral administration of 5.0 mg copper was studied in plasma from 12 normal adults. Blood samples were collected at 30 min intervals over a period of 240 min after two basal measurements taken at time = -30 and time = 0 min. Six subjects responded to the stimulus with increased growth hormone secretion, revealing a positive correlation with plasma copper levels. The other six subjects presented a similar rise in plasma copper levels but no increase in plasma growth hormone levels. These results suggest that acute, high blood copper levels can increase basal growth hormone secretion in normal individuals, presumably by acting on the hypothalamic center.

Adult↗
PubMed1985

Amino acid patterns in the plasma and ascitic fluid of cirrhotic patients.

Amino acid levels were measured in the plasma and ascitic fluid of 13 alcoholic patients with liver cirrhosis and of 14 normal controls. The plasma aromatic amino acids of the alcoholic patients were not statistically different from those of the control subjects, whereas the levels of branched-chain amino acids were reduced (P less than 0.05). The values for the ratio of the muscle/liver metabolized amino acids (valine + isoleucine + leucine)/(phenylalanine + tyrosine + methionine) were statistically lower in the cirrhotic patients both in plasma and ascitic fluid (P less than 0.05). The amino acid levels in the ascitic fluid of the cirrhotic patients were slightly lower than those in the plasma of the same patients and the values for the muscle/liver metabolized amino acid ratio were similar in plasma and ascitic fluid. Aspartic acid, glutamic acid and glycine levels were higher among the cirrhotic patients (P less than 0.05). Cirrhotic patients present an alteration in amino acid metabolism which creates a different amino acid pattern in both plasma and ascitic fluid. The significance of the proposed ratio and its possible relation to hepatic failure are discussed.

Adolescent↗
PubMed1983

Studies on the bioavailability of zinc in humans: intestinal interaction of tin and zinc.

Mineral/mineral interactions at the intestinal level are important in animal nutrition and toxicology, but only limited understanding of their extent or importance in humans has been developed. An inhibitory interaction of dietary tin on zinc retention has been recently described from human metabolic studies. We have explored the tin/zinc interaction using the change-in-plasma-zinc-concentration method with a standard dosage of 12.5 mg of zinc as zinc sulfate in 100 ml of Coca-Cola. Sn/Zn ratios of 2:1, 4:1, and 8:1, constituted by addition of 25, 50, and 100 mg of tin as stannous chloride, had no significant overall effect on zinc uptake. The 100-mg dose of tin produced noxious gastrointestinal symptoms. Addition of iron as ferrous sulfate to form ratios of Sn/Fe/Zn of 1:1:1 and 2:2:1 with the standard zinc solution and the appropriate doses of tin produced a reduction of zinc absorption not dissimilar from that seen previously with zinc and iron alone, and addition of picolinic acid did not influence the uptake of zinc from the solution with the 2:2:1 Sn/Fe/Zn ratio.

Adult↗
PubMed1983

Effect of two carbohydrate:lipid ratios of diets enterally fed to chronic alcoholics.

An amino acid mixture and different energy sources were enterally fed to 14 malnourished alcoholic patients in a metabolic unit. The patients were divided into three groups: Gp I received as enteral feeding the amino acid mixture plus carbohydrates; Gp II received the same mixture plus lipids and carbohydrates; and Gp III (control) was placed on a solid-food general hospital diet. The results were evaluated by measurement of plasma amino acids and by metabolic studies of nitrogen balance. No significant differences in plasma levels of amino acids were observed for any of the three groups between admission and discharge. The nitrogen absorption and digestibility of the amino acid mixtures offered to Gp I and Gp II was significantly higher than that of the controls. No effect of the energy source on nitrogen absorption, digestibility or retention was observed. The results suggest that the amino acid solution used was well utilized by the alcoholic patients and that the energy source (carbohydrates alone or carbohydrates plus lipids) was not a critical factor in the nitrogen utilization by the chronic alcoholic patients studied.

Adult↗
PubMedDate not supplied

Urinary calcium loss in elderly men on a vegetable:animal (1:1) high-protein diet.

BACKGROUND: A high purified protein intake has been shown to induce urinary calcium loss. However, these findings could not be reproduced with a high-protein meat diet. Also, most studies have been carried out in young subjects and the applicability of their results to the elderly population on a mixed vegetable:animal diet remains unclear. OBJECTIVES: To study whether a mixed vegetable:animal high-protein intake increases urinary calcium loss in elderly volunteers, as has been shown for younger subjects on a purified high-protein intake. METHODS: Eight male volunteers, with ages ranging from 66 to 88 years, recruited from the University Hospital Geriatric Medicine Outpatients Clinic, were studied. 24-hour urinary calcium, phosphorus, and creatinine were measured during a period of usual protein intake (approximately 0.6 g/kg/day) and during 7 days of vegetable:animal (1:1) high-protein intake (2 g/kg/day). Calcium and phosphorus intake were adjusted to be kept constant (1 g/day of each) during the whole study. RESULTS: Mean calcium urinary levels did not change significantly during the study (1.89 and 1.83 mmol/24 h during the usual and high-protein diet, respectively). Urinary phosphorus and creatinine levels also remained stable throughout the entire study. CONCLUSIONS: This study has not detected any increased calcium urinary excretion in male elderly volunteers submitted to the mixed vegetable:animal high-protein diet. Therefore, it does not support the suggestion that a high-protein intake is a risk factor for urinary calcium loss in elderly men.

Age Factors↗
PubMedDate not supplied

Energy expenditure after 2- to 3-hour elective surgical operations.

UNLABELLED: Energy expenditure was measured by indirect calorimetry in 17 adult patients (8 women and 9 men) before surgery, 4 hours immediately after surgery, and 24 hours late after surgery in patients undergoing elective surgery of small-to-medium scope. MATERIAL AND METHODS: The total duration of surgery ranged from 2 to 3 hours. Repeated measures were performed on the same patient, so that each patient was considered to be his/her own control. All patients received a 5% dextrose solution (2000 mL/day) throughout the postoperative period. RESULTS: Men showed a reduction in CO2 production during the immediately after surgery period (257+/-42 mL/min) compared to before surgery (306+/-48 mL/min) and late after surgery (301+/-45 mL/min); this reduction was not observed in women. Energy expenditure was also lower in men during immediately after surgery (6.6 kJ/min). None of the other measurements, including substrate oxidation, showed significant differences. CONCLUSION: Therefore, elective surgery itself cannot be considered an important trauma that would result in increased energy expenditure. According to this study, it is not necessary to prescribe an energy supply exceeding basal expenditure during the immediate after-surgery period. The present results suggest that the energy supply prescribed during the postoperative period after elective surgery of small-to-medium scope should not exceed 5-7 kJ/min, so the patient does not receive a carbohydrate overload from energy supplementation.

Adolescent↗