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P M Farrell

Publications and source records attributed to P M Farrell.

154 records · Page 9Linked to original sources
PubMedDate not supplied

Circulating 5-hydroxytryptamine concentrations in preterm newborns.

Alterations in circulating 5-hydroxytryptamine (5-HT) concentrations play a role in the pathophysiology of respiratory failure in adults. We undertook a study to develop a micromethod and measure circulating free 5-HT concentrations in preterm newborns with and without respiratory distress. Forty-six samples of platelet-poor plasma were obtained from 29 preterm newborns with varying degrees of respiratory distress. Samples were taken on days 2-3 and 6-7 of life. For measuring 5-HT concentrations we used a precolumn sample enhancement technique followed by ion exchange HPLC with electrochemical detection. The assay allowed detection of extremely small (50 pg) amounts of 5-HT from small (0.2 ml) amounts of blood. The mean 5-HT concentration on days 2-3 was 1.77 +/-0.74 ng/ml (mean +/- 95% confidence limits) and on days 6-7 was 0.69 +/- 0.23 ng/ml. This represented a significant fall in 5-HT concentrations (P = 0.01). All of 16 paired serial samples fell with time (P = 0.006). We conclude that platelet-poor plasma 5-HT concentrations in premature newborns are low, that there is a significant decline in these values over the first week of life, and that, in contrast with adults, the presence of respiratory failure is not associated with increased free 5-HT concentrations. The low 5-HT concentrations seen in newborns may reflect the ability to increase pulmonary uptake.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Tocopherol isomers in intravenous lipid emulsions and resultant plasma concentrations.

Conflicting reports exist regarding the relative tocopherol isomer content of Intralipid ranging from 99% as alpha-tocopherol to as much as 90% as gamma-tocopherol. Our direct assay of Intralipid as well as plasma levels measured in premature infants receiving Intralipid confirm the existence of a low alpha, high gamma-tocopherol content and imply the need for alpha-tocopherol supplementation in patients receiving Intralipid, particularly the relatively tocopherol-deficient premature infant. Furthermore, the observation of abnormal erythrocyte hemolysis test values despite "normal" total tocopherol plasma concentrations may be explained by high plasma levels of non-alpha, biologically less active isomers. The quantitation of tocopherol isomers helps explain this discrepancy and suggests the need for future studies of vitamin E status to employ measurements of tocopherol isomers in reporting results.

Birth Weight↗
PubMedDate not supplied

Mild peripheral neuropathy but biochemical chromium sufficiency during 16 months of "chromium-free" total parenteral nutrition.

A 6-yr, 4-month-old boy was started on total parenteral nutrition (TPN) because of chronic diarrhea. The TPN regimen (3 liter/day) initially included supplemented Cr (3 micrograms/day) in addition to standard components (including FreAmine III). At age 8 yr, 8 months, the serum Cr level was elevated: 3.7 ng/ml (normal 0.03-0.85). A repeat level at the same time by another commercial laboratory was also high (7.0). Cr supplementation was stopped. At age 10 yr, he was noted to have mild peripheral neuropathy although glucose tolerance was excellent (alpha-linolenic acid was undetectable in the plasma). Cr status was reevaluated in a research lab. The serum level was 1.4 ng/ml (normal 0.05-0.4). The urine chromium excretion was 1.27 micrograms/day (normal 0.22). The TPN regimen (unsupplemented with Cr) provided 4 micrograms/day. Normal Cr intake is about 60 micrograms/day with 0.4% absorption (net 0.24 microgram/day). We conclude that Cr contamination of standard PN fluid may prevent biochemical evidence of low Cr status. In addition, alpha-linolenic acid-free parenteral nutrition for 46 months was not associated with clinically significant neurological dysfunction.

Child↗
PubMedDate not supplied

An experimental model for studies of fetal maldevelopment in the diabetic pregnancy.

Values for plasma glucose and serum insulin in fasting conditions and glucose disappearance rates during an intravenous glucose tolerance test were obtained from 54 adult female rhesus monkeys. Some of these animals were subsequently made diabetic by intravenous infusion of streptozotocin (STZ). A single treatment with STZ (47.5 mg/kg) was consistently effective in ten animals for inducing severe hyperglycemia and diminished insulin response to glucose infusion. One of four additional animals became significantly glucose intolerant after a single treatment with STZ (30 mg/kg) and three of three animals became glucose intolerant after two treatments at this dosage. The greater effectiveness of STZ for inducing severe diabetes mellitus in the present study compared with previous investigations using nonhuman primates was attributed to rapid mixing and infusion of STZ with proven diabetogenic activity. Severely diabetic animals have been successfully maintained by daily subcutaneous injections of a combination of NPH and regular insulin. Fetuses of monkeys treated with STZ before conception were hyperglycemic and hyperinsulinemic, and four of these six fetuses were large for gestational age. Preliminary data suggest that fetal lung glycogen concentrations were elevated in these animals compared with controls at 145 days of gestation. It is concluded that the rhesus monkey treated with STZ before pregnancy represents a useful model for studies of fetal maldevelopment in pregnancies complicated by varying degrees of maternal diabetes.

Animals↗
PubMedDate not supplied

Nutrition in cystic fibrosis.

The goal of nutritional care for the CF patient should be to support normal growth and development, even if the patient has pancreatic insufficiency. By optimizing nutritional habits, using potent pancreatic enzyme supplements effectively and treating patients with appropriate micronutrient supplements, physicians should be able to prevent malnutrition and enhance the general health of cystic fibrosis patients.

Cystic Fibrosis↗