PubMed Health⌕ Search

Biomedical subjects

C E Menendez

Publications and source records attributed to C E Menendez.

15 recordsLinked to original sources
PubMed1992

Glycine, leucine, and phenylalanine flux in low-birth-weight infants during parenteral and enteral feeding.

Kinetics of three amino acids with different sites and characteristics of metabolic regulation were studied in low-birth-weight infants during enteral and parenteral feeding regimens typical of clinical practice. Primed constant infusions of [15N]glycine, L-[1-13C]leucine, and L-[1-13C]phenylalanine were administered simultaneously by the same route as the feeding, with isotope enrichment measured in urine over 12 h. The effect of feeding regimen was specific to each amino acid (mean +/- SD): glycine flux was lower during parenteral feeding (470 +/- 15 vs 561 +/- 69 mumol.kg-1.h-1, P less than 0.05), leucine flux was unaffected (360 +/- 77 vs 388 +/- 78 mumol.kg-1.h-1), and phenylalanine flux was higher (106 +/- 29 vs 56 +/- 6 mumol.kg-1.h-1, P less than 0.01). Kinetics were influenced by the interaction of several factors, including amino acid intake and routes of feeding and tracer administration. Glycine was most affected by route of feeding and phenylalanine was most affected by intake whereas leucine was little affected. Estimates of whole-body protein turnover calculated from leucine and phenylalanine were different; thus calculations of protein turnover from kinetics of a single amino acid should be interpreted with caution.

Amino Acids↗
PubMed1990

Urine collection as an alternative to blood sampling: a noninvasive means of determining isotopic enrichment to study amino acid flux in neonates.

The validity of measuring isotopic enrichment of amino acids in urine was tested in neonates during different feeding regimens and tracer administration protocols, and with different amino acid tracers. Twenty infants, fed enterally or parenterally, were given primed, constant infusions of 15N-glycine, L-[1-13C]leucine, and L-[1-13C]phenylalanine. Urine was collected every 2 h for 16 h. Blood was sampled only when required clinically. At baseline, enrichment in plasma and urine did not differ for any amino acid. At isotopic steady state, leucine enrichment was similar in plasma and urine, while the agreement was slightly weaker for glycine and phenylalanine, probably because of problems inherent in drawing blood samples from neonates. Study protocol did not affect the agreement. Since urine collection involves minimal invasive procedures, this approach could facilitate more indepth tracer studies in infants and children.

Amino Acids↗
PubMed1986

Compliance of insulin-dependent diabetics with a low-fat diet.

Compliance with medical therapy is widely researched yet unpredictable. When counseled by a dietitian to begin a low-fat (25%) diabetic diet, subjects significantly decreased fat intake but did not achieve the prescribed 25% fat level. The significantly lower fat intake after instruction identified the registered dietitian as an effective behavioral change agent. Six compliance predictors obtained at an initial interview accounted for 77% of the variance in compliance.

Adult↗
PubMed1984

Mucocutaneous lymph node syndrome.

A 3-year-old child presented with a short clinical history of fever and diffuse cervical lymphadenopathy, and the diagnosis of mucocutaneous lymph node syndrome was reached. We include a discussion of the case history and a brief review of this disorder.

Child, Preschool↗
PubMed1983

Ethanol suppresses the postcastration rise in serum luteinizing hormone in male rats.

The effects of short-term administration of ethanol on serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) concentrations were studied in castrated male rats. After 5 days of intraperitoneal administration of ethanol, serum LH concentrations were significantly lower than those of the saline-treated controls. Ethanol suppressed the progressive rise in serum LH concentrations that normally occurs after castration. Serum FSH concentrations tended to be higher after ethanol administration, but these differences were not significantly different from those of the saline-treated control animals. Ethanol has a potent and direct inhibitory effect on the hypothalamic-pituitary component of the male reproductive axis even when it is administered for a relatively short period of time.

Animals↗
PubMed1975

Defects of taste and smell in patients with hypothyroidism.

Taste and smell functions were measured in 18 unselected patients with untreated primary hypothyroidism, and in 15 of the 18 patients after treatment with thyroid hormones. Before treatment, 9 of the 18 patients (50 per cent) were aware of some alteration in their sense of taste, and 7 of the 18 patients (39 per cent) were aware of some alteration in their sense of smell. Distoritions of tase (dysgeusia) and smell (dysosmia) were frequent complaints among the untreated patients; dysgeusia was observed by 7 patients (39 per cent) and dysosmia by 3 patients (17 per cent). Median detection and recognition thresholds for four taste stimuli salt (sodium chloride), sweet (sucrose), sour (hydrochloric acid) and bitter (urea), and for two smell stimuli (pyridine and nitrobenzene), were determined in each patient before and after treatment with thyroid hormones. Before treatment, decreased taste acuity (hypogeusia) for at least one stimulus was observed in 14 of the patients (83 per cent); the most common abnormalities were in the detection and recognition of bitter stimuli. Median detection thresholds for both smell stimuli were also markedly elevated (hyposmia) before therapy. Treatment with throid hormones largely reversed both the taste and smell defects. In one patient, taste and smell abnormalities were completely corrected after 16 days of treatment with thyroxine. This study indicates that taste and smell defects are common clinical abnormalities in primary hypothyroidism, and suggests that these defects may contribute to the anorexia and lack of interest in eating which are frequently observed.

Adult↗