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Biomedical subjects

S Gordon

Publications and source records attributed to S Gordon.

At least 631 records · Page 35Linked to original sources
PubMed1965

Dissociation of kappa- and lambda-chains from reduced human immunoglobulins.

1. The light chains of human immunoglobulin (Ig) exist in two forms, kappa (type K) and lambda (type L). The two types of chains can be partially separated by taking advantage of the fact that lambda-chains, for the most part, dissociate from reduced Ig at higher pH than do the kappa-chains. The same difference in dissociation of type K and L chains was observed with myeloma IgG and IgA proteins, but not with pathological IgM proteins. 2. When analysed in urea-glycine starch gels, pH7, both kappa- and lambda-chains show ten electrophoretic bands having the same mobilities as those of the whole light-chain subfractions. Normal kappa- and lambda-chains show similar differences in overall amino acid composition to those previously found with myeloma kappa- and lambda-chains and type K and L Bence-Jones proteins.

Journal Article↗
PubMedDate not supplied

The metabolic fate of triamcinolone acetonide in laboratory animals.

The metabolic fate of 9-fluoro-11beta,16alpha,17,21-tetrahydroxy-1,4-pregnadiene-3,20-dione cyclic 16,17-acetal with 2(-14)C-acetone, triamcinolone acetonide (TA) was studied in rabbits, dogs, monkeys and rats and found to be qualitatively similar in all species. In the dog, rat and monkey the major excretory route was the feces irrespective of the mode of administration. In the rabbit the excreted radioactivity was equally distributed between urine and feces. The metabolites were isolated by preparative thin layer chromatography, located by autoradiography, eluted and analyzed by MS, IR, UV and NMR. The major metabolites of triamcinolone acetonide (TA) were identified as the C-21 carboxylic acids of TA and of the 6beta hydroxy-TA, (6BETA-OH-TA) and the previously identified (1,2) 6beta-OH-TA. In addition MS and UV data indicate the presence of 9-fluoro-11beta,16alpha, 17-trihydroxy-3,20-dioxo-1,4,6-pregnatrien-21-oic acid cyclic 16,17 acetal with 2(-14)C-acetone.

Animals↗
PubMedDate not supplied

Acute management of glycogen storage disease type Ia.

Rapid metabolic deterioration may occur in patients with some glycogen storage diseases (GSDs) regardless of presenting complaint. Hepatic, renal, and hemostatic abnormalities may also complicate diagnosis and treatment of trauma victims. We report the case of a man presenting with an epidural hematoma and a history of GSD type Ia.

Adult↗
PubMedDate not supplied

Development of techniques to analyse the formation of HIV provirus in primary human macrophages.

The formation of provirus is an important early event in the life cycle of a retrovirus. We describe a system using PCR for the analysis of this process in primary human macrophages infected in vitro with HIV. We show that products of the first template switch can be detected within 8 h after infection at low multiplicity. The methods described provide a rapid assay of infection with HIV and can be applied in the investigation of a number of aspects of HIV replication in macrophages.

Base Sequence↗
PubMedDate not supplied

Nutritional outcomes following pediatric intestinal transplantation.

BACKGROUND: This study sought to describe the long-term nutritional outcomes of children after intestinal transplant (SBT). METHODS: Between 1991 and March 2005, 30 children received 33 SBT at a single center. Eligibility criteria included patient and graft survival >6 months. Weight, height, albumin, prealbumin, zinc (Zn), and essential fatty acid (EFA) levels were reviewed retrospectively. RESULTS: The 19 patients who met inclusion criteria had a median age at SBT of 2.9 years. The majority of patients were male, Latino, transplanted for necrotizing enterocolitis and received combined liver-SBT. All patients were weaned off total parenteral nutrition to elemental formula at a mean of 39 days post-SBT. Seventeen of 19 patients were Zn deficient and four patients were EFA deficient post-SBT. CONCLUSIONS: Pre-SBT most subjects were significantly deficient in anthropometric and biochemical parameters. Post-SBT the mean Z score for weight and height improved significantly at year 1, then leveled off in year 2. Serum protein levels improved from pre-SBT, yet remained low-normal. Zn deficiency was seen frequently after SBT and is under investigation. Children who developed EFA deficiency were on the same formula, receiving inadequate EFA supplementation. Successful SBT was associated with growth and maintenance of serum nutritional parameters but not with significant catch-up growth.

Adolescent↗
PubMedDate not supplied

The role of the macrophage in immune regulation.

The macrophage plays an important role in both the innate and acquired (humoral and cellular) immune responses. Their specialized derivatives, the dendritic cells (DCs), are uniquely potent in induction of naive T and B lymphocytes, whereas macrophages influence a range of immune responses by antigen recognition, capture, clearance and transport. They recruit haemopoietic cells to local sites of inflammation and immunity and regulate their activities. We have used various myeloid-restricted membrane antigens and receptors as markers and functional contributors to these activities, and briefly review their role in immune regulation in vivo and in vitro.

Animals↗
PubMedDate not supplied

PCR analysis of HIV1 infection of macrophages: virus entry is CD4-dependent.

Amplification of early reverse transcripts by the polymerase chain reaction has been used to measure HIV1 entry into H9 cells and primary macrophages. With a single-step method of DNA preparation, we performed time course experiments to follow the appearance of long terminal repeat DNA. In both cell types, the formation of DNA was completely inhibited by anti-CD4 antibody, confirming the requirement of CD4 for virus binding and entry, and demonstrating that there were no CD4-independent routes of infection. In agreement with previous infectivity studies, sCD4 inhibited the entry of IIIB into H9, but only partially blocked Ba-L into macrophage when used at a comparable dose.

Antibodies↗
PubMedDate not supplied

The National Human Exposure Assessment Survey (NHEXAS) study in Arizona--introduction and preliminary results.

The objective of the National Human Exposure Assessment Survey (NHEXAS) in Arizona is to determine the multimedia distribution of total human exposure to environmental pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) for the population of Arizona. This was accomplished by studying a probability-based sample of the total population in Arizona with a nested design for the different stages of sampling (954 Stage I, 505 Stage II, and 179 Stage III participants). This report compares the study population demographics with those from the U.S. Census and provides preliminary data on the distributions of the example pollutant for each class, lead for metals, chlorpyrifos for pesticides, and benzene for metals. The probability-based sample age and gender demographics compare reasonably well with the Census data (1990 Census and 1996 Census Estimate). The race/ethnicity compared less well with 21% Hispanics in the 1996 Census Estimate and 42% Hispanics in the entire NHEXAS-Arizona sample and 30% Hispanics as Stage III participants for this study. The chemical analyses of the various media (yard soil, foundation soil, house dust, indoor air, outdoor air, drinking water, food, and beverage) show generally low levels of the representative pollutants. The 50th percentiles of the distributions are generally near or below the analytical detection limits, and applicable Federal action limits were rarely exceeded.

Adolescent↗
PubMedDate not supplied

On predicting multi-route and multimedia residential exposure to chlorpyrifos and diazinon.

This paper formulates regression models and examines their ability to associate exposures to chlorpyrifos and diazinon in residences with information obtained from questionnaires and environmental sampling of the National Human Exposure Assessment Survey Arizona (NHEXAS-AZ) database. A knowledge-based list of 29 potential exposure determinants was assembled from information obtained from six questionnaires administered in the course of the study. This list was used to select the independent variables of each model statistically and electronically. Depending on the data type of dependent and independent variables, four classes of regression models were developed to determine desired associations. Route-specific exposures were estimated using the indirect method of exposure estimation and measurements from the NHEXAS-AZ field study. The stepwise procedure was used to construct regression models. Significance level at P=0.10 was used for entry and retention of independent variables in a model. Twelve significant regression models were formulated to quantify associations among exposures and other variables in the NHEXAS-AZ database. Route-specific exposures to pesticides associate significantly with questionnaire-based variables such as preparation of pesticides, use of pesticide inside the house, and income level; and with concentration variables in three media: dermal wipe, sill wipe, and indoor air. Models formulated in this study may be used to estimate exposures to each of the pesticides. Yet, the use of these models must incorporate clear statements of the assumptions made in the formulation as well as the coefficient of determination and the confidence and prediction intervals of the dependent variable.

Activities of Daily Living↗
PubMedDate not supplied

Automated donor-recipient identification systems as a means of reducing human error in blood transfusion.

Clerical and administrative errors are the most common mistakes in blood banking, with errors of sample or patient identification accounting for the majority of mistakes. In an effort to reduce the incidence of human errors, three automated donor-recipient identification systems were developed and were evaluated under clinical conditions. After two years of development and bench testing, each set of equipment was tested, along with established procedures, at a large clinical center, a medium-sized community hospital and a regional donor center. Although none of the systems, as tested, proved acceptable under clinical conditions, a great deal was learned about prototype equipment testing in the clinical setting. Future development of identification systems for clinical use should respond to carefully defined problems, apply in all areas of the hospital or donor center, and be convenient and reliable. The development of the equipment should involve established manufacturers and be subject to exacting preclinical testing.

Blood Banks↗