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Biomedical subjects

R A Jacob

Publications and source records attributed to R A Jacob.

85 records · Page 5Linked to original sources

Zinc status and vitamin A transport in cystic fibrosis.

Zinc status and the retinol transport system were examined in 18 retinol supplemented cystic fibrosis (CF) patients and 40 age-matched controls. Plasma vitamin A was significantly lower in the CF group as compared to the controls and correlated positively with plasma retinol-binding protein (RBP) in both the CF and control groups. Plasma zinc of the CF group was not significantly lower than controls whereas hair zinc was. Plasma zinc was positively correlated with plasma RBP, vitamin A, and albumin in the CF group but not in the controls. Plasma concentrations of vitamin A, RBP, albumin, and zinc decreased with age in the CF group but not in the controls. The data support previous suggestions that low plasma vitamin A levels in CF are due to defects in the retinol transport system. The zinc status of the CF groups as a whole was judged to be low-normal however a subgroup of CF patients were in the marginal to deficient category. This subgroup also had lower levels of plasma vitamin A and RBP. The data suggest that zinc may be a contributing factor in the low plasma vitamin A/RBP levels of CF patients with marginal or deficient zinc status.

Adolescent↗

Zinc deficiency in pregnant rhesus monkeys: effects on behavior of infants.

Zinc deprivation from day 110 to 150 of gestation in rhesus monkeys resulted in rash, alopecia, anorexia, decreased feed efficiency, and low plasma zinc in the mothers. Infants of the dams that had been deprived of zinc during gestation displayed a more rapid postnatal growth rate than infants of the control mothers. Infants of the zinc-deprived dams played and explored less than the control infants. They also associated with their mothers a greater percentage of the time and were less active. This study has shown that third trimester maternal zinc deprivation in nonhuman primates can impair behavioral development of offspring.

Animal Nutritional Physiological Phenomena↗

Leukocytic endogenous mediator in Crohn's disease.

Reduced concentrations of plasma zinc associated with elevated levels of serum leukocytic endogenous mediator activity were found in 17 patients hospitalized with acute exacerbation of Crohn's disease. Neither the decrease in plasma zinc nor the increase in leukocytic endogenous activator activity in nine outpatients with quiescent disease was significant. Leukocytic endogenous mediator activity may be increased in inflammatory conditions as well as in microbial infections. Although zinc deficiency may be common in patients with Crohn's disease, exclusive reliance on circulating zinc levels to assess zinc nutriture in active Crohn's disease may be misleading.

Adolescent↗

Fetal malnutrition: an appraisal of correlated factors.

Fetal malnutrition has emerged as a significant health problem over the past decade. Present evidence suggests that maternal environment plays the major etiologic role in fetal malnutrition. The association of fetal malnutrition in mothers with chronic hypertension is well known, but fetal malnutrition is associated with maternal hypertension in less than 25 per cent of cases. Among a group of 182 pregnant women studied at midpregnancy for blood levels of vitamins, trace metals, proteins, amino acids, and parameters of maternal leukocyte energy metabolism, it was found that the concentration of 10 amino acids, alpha-1-globulin, zinc, and total carotenes had a statistically significant relationship to fetal growth. Similarly significant correlations were found for maternal leukocyte adenosine disphosphate, phosphofructokinase activity, ribonucleic acid (RNA) synthesis, and cell size. Maternal cigarette smoking was correlated with reduced fetal growth. Analysis showed that there was a significant reduction in leukocyte RNA synthesis and phosphokinase activity and in the plasma levels of 14 amino acids, and carotene in smoking mothers. This information lends support to the hypothesis that factors which affect the growth of fetal cells also will affect maternal leukocytes in a definable way.

Adolescent↗

Growth retardation and zinc nutrition.

Based on a previous report of a zinc deficiency syndrome in children characterized by low hair zinc, anorexia, poor growth, and hypogeusia, 12 children attending a pediatric endocrinology clinic for growth retardation and judged as having short stature as a variant of normal (SVN) were evaluated as to their zinc nutriture to learn whether zinc deficiency was a contributory factor. None was found to have the above syndrome, although one child did have a hair zinc concentration below 70 mug/g. The mean hair zinc of the SVN subjects was lower than the hair zinc of 40 apparently normal adolescents, 131+/-37 mug/g vs. 168+/-44 mug/g (P less than 0.02), but there was no difference found in plasma levels of zinc or in taste acuity. In contrast, five patients with total growth arrest secondary to juvenile Crohn's disease (CD) were found to have multiple findings consistent with zinc deficiency including low plasma zinc, low hair zinc, or hypogeusia.

Adolescent↗

Synovial chondrometaplasia. A case report.

Synovial chondrometaplasia is an uncommon benign lesion most commonly affecting males in the 20 to 60 age range. The youngest heretofore reported patient is 14 years of age. In a male patient of 7 years, 2 months, with a bone age of 5 years with left elbow involvement, there was no history of antecedent trauma. The presenting complaint was enlargement of the elbow with limitation of motion. At surgery 54 osteocartilaginous bodies were removed, some of which were still covered with synovium. Eighteen months following an anterior synovectomy, there was 5 degrees to 128 degrees of pain-free elbow flexion and full painless forearm pronation and supination with no recurrence of the disease.

Adolescent↗