ABSTRACT
Results are presented from the Galveston Low Birthweight Survey (GLOWBS) Study, a tri-ethnic survey (N = 1,179) of live, single births, conducted in Galveston, Texas, from 1986 to 1987. Four principal findings emerged pointing to a persistent black risk for low birthweight (less than 2,500g). First, black infants (2,997g) have significantly lower mean birthweight than either Anglos (3,281g) or Hispanics (3,270g). Second, blacks are at significantly higher risk of low birthweight than nonblacks (risk ratio = 1.71). Third, despite controlling for a variety of pregnancy- and health-related, psychosocial, socioeconomic, and health services factors (including even gestational length), being black still exerts a significant, inverse effect on birthweight (beta = -0.137). Fourth, of the above factors only gestational length (R2 = 0.39) accounts for more than a negligible amount of the total variance in birthweight among blacks. These findings are discussed, and several lines of follow-up research are proposed.
Subject(s)
Black or African American , Infant, Low Birth Weight , Data Collection , Humans , Infant, Newborn , Risk Factors , TexasSubject(s)
Behavior , Diet , Animals , Brain/physiology , Food , Humans , Nutritional Physiological Phenomena , Research DesignSubject(s)
Lead/blood , Water Pollutants, Chemical/analysis , Water Pollutants/analysis , Body Burden , Boston , Humans , Infant , Lead/analysis , Ohio , Water SupplyABSTRACT
Pharmacokinetics of cephalexin were studied in 7 pediatric and 4 adult patients with cystic fibrosis (CF) and 4 normal adult volunteers. Cephalexin, 250-500 mg, was given as a single dose in suspension. The area under the cephalexin serum concentration-time curve normalized for dose per kilogram averaged 0.185, 0.242, and 0.272 ml/min/kg-1 in pediatric CF patients, adult CF patients, and normal adults, respectively (p greater than 0.05). A threefold interindividual variation was observed in cephalexin renal clearance in CF patients. Renal clearance of cephalexin averaged 5.85 ml/min/kg in pediatric and 4.61 ml/min/kg in adult CF patients (p greater than 0.05). Elimination half-life of cephalexin averaged 0.74, 0.76, and 1.04 h in pediatric patients, adult patients, and normal adults (p greater than 0.05). Cephalexin was well absorbed based on a mean 24-hour urinary recovery of 89 and 93% in pediatric and adult patients. A trend for higher renal clearance of cephalexin was observed among pediatric compared to adult patients. These results indicate that clearance of cephalexin may not increase in patients with CF of minimal severity characterized by an excellent Shwachman score.
Subject(s)
Cephalexin/metabolism , Cystic Fibrosis/drug therapy , Adult , Cephalexin/therapeutic use , Child , Cystic Fibrosis/metabolism , Female , Half-Life , Humans , Kidney/metabolism , Kinetics , MaleSubject(s)
Fat Emulsions, Intravenous/administration & dosage , Fat Emulsions, Intravenous/therapeutic use , Infant, Low Birth Weight , Body Weight , Fat Emulsions, Intravenous/adverse effects , Humans , Infant, Newborn , Infant, Small for Gestational Age , Metabolic Clearance Rate , Nitrogen/metabolism , Parenteral Nutrition, Total , Respiration/drug effects , Triglycerides/bloodSubject(s)
Intestinal Absorption , Tetracyclines/metabolism , Adult , Capsules , Female , Humans , Male , Middle Aged , Tetracyclines/administration & dosageABSTRACT
Some of the serum proteins which bind to heparin and contribute to the pH 5.57 "heparin binding capacity" of human serum are glycoproteins; those from cystic fibrosis serum were found to be 27% higher in fucose (methylpentose) content, 27% lower in sialic acid content, and 31% lower in hexose content when compared to heparin-precipitated serum glycoproteins from normal control subjects. Hexosamine content of the heparin-precipitated serum glycoproteins was the same. Results of this preliminary investigation indicate that altered carbohydrate composition in serum glycoproteins may affect significantly their heparin binding capacity.
Subject(s)
Blood Proteins/metabolism , Cystic Fibrosis/blood , Glycoproteins/biosynthesis , Heparin/blood , Adolescent , Adult , Carbohydrates/blood , Cystic Fibrosis/metabolism , Female , Glycoproteins/blood , Humans , Male , Protein BindingABSTRACT
A method for estimating a 'heparin binding capacity' of human serum is described. When human serum is diluted with a low ionic strength, heparin-containing buffer at pH 5.5, protein-heparin electrostatic complexes form in solution with subsequent formation of insoluble aggregates which can be collected by centrifugation. Quantitative determination of the relative amounts by weight of protein and heparin in the insoluble heparin-protein aggregates permits estimation of a combining ratio at which serum proteins bind with heparin to precipitate from solution. This weight combining ratio of protein and heparin is a quantitative measure of the total affinity for heparin of all proteins in serum which bind heparin at pH 5.57 to form an insoluble complex. An unusually high affinity for heparin by an abnormal serum protein or an increase in amount of a normally-occuring, high heparin-affinity, serum protein would alter the average protein: heparin combining ratio and increase the 'heparin-binding capacity' of human serum. The converse would be true for serum proteins having a low affinity for heparin, lowering the 'heparin-binding capacity' of human serum. The described method was used to evaluate the 'heparin-binding capacity' of serum proteins in normal individuals and in persons with cystic fibrosis.
