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Biomedical subjects

R Carlson

Publications and source records attributed to R Carlson.

At least 19 recordsLinked to original sources

Thermal desorption cold trap-injection in high-resolution gas chromatography: multivariate optimization of experimental conditions.

In studies of low concentrations of volatile compounds in air, the method of adsorption on porous polymers and determination by thermal desorption cold trap-injection high-resolution gas chromatography is finding increasing application. Factors considered important for injection and chromatographic separation of volatile compounds by this method were investigated with the use of multivariate techniques. For the amount injected on to the chromatographic column, the factors of main importance were found to be the temperature of the injection block, the thickness of the internal coating of the cold trap and the flow-rate. Strong interaction effects were noted. For the sharpness of the chromatographic peaks, the flow-rate was the most important factor.

Air Microbiology

The major histocompatibility complex class I antigen-binding protein p88 is the product of the calnexin gene.

A 90-kDa phosphoprotein (p90) of the endoplasmic reticulum was identified by a monoclonal antibody generated against human hepatoma cells. Pulse-chase experiments with [32P]phosphate and [35S]methionine demonstrated that p90 formed both stable and transient complexes with other cellular proteins, suggesting its role as a molecular chaperone. This protein associates with heavy chains of major histocompatibility complex class I proteins, suggesting that it is the human homolog of the recently described 88-kDa protein that transiently associates with murine class I molecules in the endoplasmic reticulum. The p90 protein also associates in B lymphocytes with membrane immunoglobulin mu heavy chains and may serve as a chaperone for many membrane-bound polypeptides. A partial human p90 cDNA was cloned from a lambda gt11 expression library and identified as the human homolog of calnexin, a major canine calcium-binding protein found to be associated with the signal-sequence receptor in endoplasmic reticulum membranes.

Amino Acid Sequence

Monoclonal antibodies specific for mercuric ions.

Monoclonal antibodies (mAbs) that react with soluble mercuric ions have been produced by injection of BALB/c mice with a hapten-carrier complex designed to maximize exposure of the metal to the immune system. Three hybridomas producing antibodies that reacted with bovine serum albumin (BSA)-glutathione-HgCl, but not with BSA-glutathione, were isolated from the spleen of a mouse given multiple injections with glutathione-HgCl conjugated to keyhole limpet hemocyanin. Stable subclones were established from two of these antibodies, designated mAb 4A10 and mAb 1F10. The binding of both antibodies to immobilized BSA-glutathione-HgCl was inhibited by soluble HgCl2, and dissociation constants for mercuric chloride binding were 2.3 and 3.7 nM for mAbs 4A10 and 1F10, respectively. Both antibodies bound mercuric acetate with similar affinities, demonstrating that the antibodies were capable of binding to mercuric ions in the presence of a different counterion than the one used in the immunogen. Reactions were not observed with other metal cations by either antibody. These data demonstrate the successful induction of antibodies that react very specifically with mercuric ions in solution regardless of the presence of a carrier.

Amino Acid Sequence

Multicenter phase II trial of brequinar sodium in patients with advanced squamous-cell carcinoma of the head and neck.

A total of 19 patients with advanced squamous-cell carcinoma of the head and neck who had not previously been exposed to chemotherapy were treated with brequinar sodium as first-line chemotherapy. Brequinar was given intravenously at a median weekly dose of 1,200 mg/m2. The toxicity was moderate, with 7 patients (37%) experiencing grade 3 or 4 toxicity. In all, 16 patients who were evaluable for efficacy showed no objective response. We conclude that brequinar given at this dose and on this schedule has no significant activity in advanced squamous-cell carcinoma of the head and neck.

Adult

Nurse-physician collaboration: solving the nursing shortage crisis.

The current severe nursing shortage in the United States has many causes and its solution requires new strategies. Collaboration among the American Association of Critical-Care Nurses (AACN), the Society of Critical Care Medicine (SCCM) and the American College of Cardiology (ACC) has provided a model for the multidisciplinary approach needed. Nurse-physician collaboration is an important strategy to address the ongoing shortage.

Critical Care

Multicenter phase II trial of brequinar sodium in patients with advanced melanoma.

Seventeen patients with advanced melanoma and no prior exposure to chemotherapy were treated with brequinar sodium as first-line chemotherapy. Brequinar was given at a median weekly dose of 1200 mg/m2 intravenously. In 14 patients evaluable for efficacy, there were no objective responses. The toxicity was moderate. We conclude that, at this dose and schedule, brequinar has no activity in advanced melanoma.

Adult

100 percent smokefree New Jersey restaurants.

The overwhelming majority of New Jerseyans are not smokers and they want and deserve protection. Smokefree policies benefit restaurants. Smokers, too, support controls. Legal action, education, and public demand will make New Jersey restaurants smokefree.

Humans

Nurse/physician collaboration: solving the nursing shortage crisis.

This summary article discusses the status of the nursing shortage in the United States, with emphasis on successful strategies to address it. Liaisons between the American Association of Critical-Care Nurses (AACN) and the Society for Critical Care Medicine, as well as with the American College of Cardiology, are highlighted, with primary emphasis on the strategy of nurse-physician collaboration.

Critical Care

Detection of mercuric ions in water by ELISA with a mercury-specific antibody.

An immunoassay that detects mercuric ions in water at concentrations of 0.5 ppb and above is described. The assay utilizes a monoclonal antibody that binds specifically to mercuric ions immobilized in wells of microtiter plates. Within the range of 0.5-10 ppb mercury, the absorbance in the enzyme-linked immunosorbent assay (ELISA) is linear to the log of the mercuric ion concentration. The quantitation of mercury by ELISA correlates closely with results from cold-vapor atomic absorption. Other divalent metal cations do not interfere with the assay, although there is interference in the presence of 1 mM chloride ions. The optimum pH for mercury detection is 7.0, although 2 ppb mercury can be detected over a wide pH range. The assay is as sensitive as cold-vapor atomic absorption for mercury detection and can be performed with only 100 microliters of sample.

Animals

A socio-psychiatric profile of emergency service patients.

A study of patients using the psychiatric emergency services of the Royal Ottawa Hospital was undertaken to determine their demographic and clinical characteristics, correlations between the two and comparisons with other studies. Special clinical forms of every fifth patient seen were analyzed and the data presented. These data are useful in the planning of and establishing and operating a psychiatric emergency service with an attached short-term inpatient unit, as well as assessing the feasibility and value of crisis intervention and brief psychotherapy in treating patients quickly.

Adolescent

A new model for measuring breeding genetic distance. II. Polygenic traits.

The breeding genetic distance measure of a single locus (Carlson & Welch, 1977) is extended to polygenic traits. For two populations with means -x and approximately x, theta(-x, approximately x) is defined as the size of the largest subpopulation with mean approximately x which can be (artificially) selected from a population with mean -x. The distance is defined as 1--theta(-x, approximately x). It is shown that theta(-x, approximately x) can be calculated from truncation selection and formulas (two loci) and tables (three and four loci) are given. Values for theta(-x, approximately x) based on a normal approximation are seen to be adequate for most cases. The measure is applied to a data example (human skin colour) and to a discussion of the idea of 'genetic inertia'.

Gene Frequency

A new model for measuring breeding genetic distance.

A model is proposed for measuring the genetic 'distance' between two populations having gene frequencies p and p. The measure of distance is based on a hypothetical selection process as follows: From population P a subpopulation P can be selected having gene frequency p. Let Po be the largest subpopulation yielding gene frequency p, then the relative size of Po to p--denoted by thetao (p,p)--is a measure of the 'closeness' of populations having gene frequencies p and p, and 1-thetao (p,p) whould be a reasonable measure of genetic distance. We show that the calculation of thetao (p,p) is a special case of the linear programming problem and derive algebraic expressions for thetao (p,p) in the two-allele case. We discuse some of the implications of the use of this measure of distance and compare it to others which have been proposed. We use linear programming methods to calculate genetic distance for three alleles.

Alleles