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Biomedical subjects

M E Moore

Publications and source records attributed to M E Moore.

At least 37 records · Page 2Linked to original sources
PubMed1993

Factors that affect alpha particle detection in continuous air monitor applications.

An experimental study was conducted to characterize the full-width half-maximum values, peak shapes, and peak shifts of the energy spectra from alpha emitters in the forms of particulate matter on sampling filters and electro-deposited plated sources. Monodisperse 1.0-microns anhydrous uranium acetate aerosol particles were collected on seven types of sampling filters. Full-width half-maximum values at atmospheric pressure varied from 373 keV for a 3-microns pore size Fluoropore filter to 584 keV for a glass fiber filter. Monodisperse uranium acetate aerosols from 1.2-8.1 microns were collected on Millipore 1.2-microns pore size membrane filters to examine the self-absorption effect. Under vacuum, the corresponding full-width half-maximum values ranged from 241-1,011 keV. Successively heavier mass loadings of monodisperse 1.8-microns uranium acetate particles from 13.7-127 micrograms cm-2 caused the values to increase from 420 to 580 keV. With an electroplated 23.9-mm-diameter 239Pu source and a 25.4-mm detector, the distance between source and detector was incrementally increased from 3.2 to 6.4 mm--a range of distances that is typical of those found in alpha continuous air monitors. At atmospheric pressure, the values increased from 280 to 330 keV and the detector efficiency decreased from 30.5% to 20.9%. Tests with various sizes of sources and detectors suggest that a continuous air monitor should be designed so that the two are of approximately equal size.

Air Pollutants, Occupational↗
PubMed1992

A continuous sampler with background suppression for monitoring alpha-emitting aerosol particles.

A continuous air monitor has been developed that includes provisions for improving the detection of alpha-emitting aerosol particles in the presence of radon/thoron progeny that are unattached to ambient aerosol particles. Wind tunnel tests show that 80% of 10-microns aerodynamic equivalent diameter particles penetrate the flow system from the ambient air to the collection filter when the flow rate is 57 L min-1 (2 cfm) and the wind speed is 1 m s-1. Uniformity of aerosol collection on the filter, as characterized by the coefficient of variation of the areal density deposits, is less than 15% for 10-microns aerodynamic-equivalent-diameter aerosol particles. Tests with unattached radon daughters in a flow-through chamber showed that approximately 99% of the 218Po was removed by an inlet screen that is designed to collect radon daughters that are in the size range of molecular clusters. The inlet screen offers the opportunity to improve the signal-to-noise ratio of energy spectra in the regions of interest (subranges of the energy spectrum) of transuranic elements and thereby enhance the performance of background compensation algorithms.

Aerosols↗
PubMed1990

Autocrine regulation of rheumatoid arthritis synovial cell growth in vitro.

Rheumatoid arthritis (RA), and not osteoarthritis (OA) synovial cells proliferate in serum-free medium, a finding that suggests that, in vitro, RA synovial cells may be stimulated to grow by the continuous autocrine production of at least one polypeptide growth factor. Adding monoclonal antibody 1D11.16, or rabbit polyclonal anti-tumor growth factor beta (anti-TGF-beta) antibodies (both neutralizing antibodies to TGF-beta 1 and TGF-beta 2) to RA synovial cells, in culture, caused a significant reduction in cell growth, an effect not seen when other growth factor antibodies (platelet-derived growth factor [PDGF], epidermal growth factor [EGF], or EGF receptor) were added to the culture medium. Taken together, these data are consistent with the concept that RA synovial cell growth in vitro is driven endogenous TGF-beta. Moreover, when EGF was added to the culture medium, this caused the numbers of RA, and not OA, synovial cells to increase significantly. This finding suggests that RA synovial cells are in G1 phase of the cell cycle; an effect that could be mediated by endogenous TGF-beta.

Arthritis, Rheumatoid↗
PubMed1990

Design of Stairmand-type sampling cyclones.

An empirical, nondimensional correlation of cut-point Stokes number (Stk0.5) and flow Reynolds number (Re) has been established for small Stairmand-type sampling cyclones. Four cyclones with body diameters of 38, 57, 89, and 140 mm were constructed and tested with monodisperse aerosols over a range of flow rates. The flow rates were chosen to provide preselected increments of particle Froude numbers. These flow rates for the four cyclones spanned the range of 9.4 to 1080 L/min and provided Froude numbers of 1.5, 2.0, 2.5, and 6.0. The resulting Reynolds numbers (based upon cyclone body diameter and inlet flow rate) covered the range of 2.1 x 10(3) to 6.4 x 10(4). Sizes of monodisperse aerosols used in this study were from 3.0- to 17.4-microns aerodynamic diameter. The graphical correlation between cut-point Stokes number and Reynolds number showed there to be no effect of Froude number (for the range of Froude numbers tested). The data have been fit by a least squares procedure to a quadratic logarithmic function. In addition to development of the empirical correlation, the results of this study also provide data pertinent to the regional deposition of liquid particles within the cyclone and to the transmission of solid particles through the cyclone. The carryover of solid, 19-microns diameter particles is only 0.5% greater than that of liquid particles of the same size.

Air Pollutants, Occupational↗
PubMed1988

Common tests for rheumatoid factors: poorly standardized but ubiquitous.

Rheumatoid factor (RF) test results reported in the College of American Pathologists' surveys for 1983-1985 lacked inter-laboratory reliability and mutual validity. Using the 4 most popular commercial kits for RF testing, participating laboratories consistently identified as "positive" or "negative" all but the weakly positive samples. A wide range of titers was reported on qualitative testing, however. One popular kit using a modified sheep red blood cell agglutination technique yielded results that differed markedly from those with other kits. Investigators apparently have paid little attention to these discrepancies. In Arthritis & Rheumatism, from 1983 to 1985, over 50% of the articles that referred directly or indirectly to RFs omitted details of RF methodology. Until a reliable RF test is adopted, it is essential that such methodologic information be specified.

Humans↗
PubMed1988

Marketing and planning in multihospital systems.

Marketing and planning functions at the corporate level of multihospital systems are examined. Drawing on the experiences of executives in 30 multihospital systems located in the United States west of the Mississippi, this article describes the differences in the marketing and planning functions by for-profit, not-for-profit, and church-owned multihospital systems; examines the impact of age, number of hospitals, and average hospital bed size of the systems; provides insights regarding the primary persons involved in the marketing and planning functions; and highlights the important future of marketing and planning by the top management of multihospital systems.

Hospital Planning↗
PubMed1987

Time dependency of endotoxin-induced resistance to transplantable tumors in mice.

A single injection of bacterial endotoxin induced cyclic changes of enhanced or reduced host reactivities, as determined in some measurements of the beneficial effects of endotoxin, such as immune potentiation or protection against lethal irradiation. The results described here show that endotoxin-induced resistance to subsequent challenge with transplantable tumors such as Lewis lung carcinoma or L1210 murine leukemia is similarly time dependent. While certain time intervals between endotoxin treatment and tumor challenge will provide significant protection, others will render the recipients highly susceptible to the same tumor. It was also observed that L1210-bearing mice have a lower resistance to endotoxin injections than tumor-free mice of the same strain.

Adenocarcinoma↗
PubMed1987

Persistently low blood retinol levels during and after parenteral feeding of very low birth weight infants: examination of losses into intravenous administration sets and a method of prevention by addition to a lipid emulsion.

Very low birth weight infants have little storage of hepatic retinol and are, therefore, highly dependent upon an exogenous supply. The recent association between low serum retinol level and bronchopulmonary dysplasia and the persistently low serum levels of retinol during total parenteral nutrition prompted a prospective study to evaluate serial changes in serum retinol levels during 1 month of total parenteral nutrition (retinol dose 455 micrograms/d) and again during 1 month of total enteral feeding (retinol dose 200 to 300 micrograms/d) in the same infants. Infants were divided into two groups. Group 1 consisted of infants weighing less than 1,000 g (n = 24) and group 2 consisted of infants weighing 1,000 to 1,500 g (n = 17). Although initial mean levels of retinol were similar in both groups (14.8 +/- 0.9 and 13.5 +/- 0.7 micrograms/dL), there was wide variation between infants. In group 1 infants, there was a significant (P less than .01) decline in retinol level by the second week of life (to 9.2 +/- 1 micrograms/dL), which persisted during total parenteral nutrition, but increased to 13.4 +/- 2 after 1 week of enteral feeding. This level was maintained throughout enteral feeding. In group 2 infants, there was no significant change in serum retinol level throughout the study. During total parenteral nutrition, several infants had retinol levels below 10 micrograms/dL, a level associated with signs of retinol deficiency in older children. Because losses of retinol are known to occur in smaller volume total parenteral nutrition solutions, it was speculated that losses of retinol in our patients were due to retinol losses in the total parenteral nutrition delivery system.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug Stability↗
PubMed1987

Relapsing polychondritis syndrome associated with pustular psoriasis, spondylitis and arthritis mutilans.

We describe the first case of pustular psoriasis, HLA-B27 positive spondylitis, arthritis mutilans, and relapsing polychondritis. The relapsing polychondritis was mild and long undetected. Relapsing polychondritis is seen not uncommonly with a variety of inflammatory skin lesions. Because of this, and because many rheumatic diseases have been observed with relapsing polychondritis, we stress that relapsing polychondritis is a syndrome and not a unique disease. Relapsing polychondritis in mild form may be fairly common; a search for signs and symptoms of chondritis should be a routine part of the workup of patients with inflammatory rheumatic diseases and dermatoses.

Arthritis↗
PubMed1986

Demonstration of glucuronic acid on brain glycoproteins which react with HNK-1 antibody.

Ependymins, a family of extracellular glycoproteins of goldfish and mammalian brain, were shown to contain N-linked complex glycan chains. These glycoproteins reacted with a monoclonal antibody, HNK-1 which recognizes a membrane antigen on a subset of human lymphocytes, myelin-associated glycoprotein glycoprotein epitope reacting with HNK-1 antibody was previously shown to include a terminal 3-sulfoglucuronosyl residue present in certain glycolipids of the nervous tissue (Chou et al., Biochem. Biophys. Res. Commun. 1985, 128, 383-388). In this report, the presence of glucuronic acid in ependymins was demonstrated by gas-liquid chromatography and mass spectrometry. We suggest that a 3-sulfoglucuronosyl residue may be the common epitope on HNK-1-reactive glycoproteins.

Animals↗
PubMed1986

Evaluation of a pediatric multiple vitamin preparation for total parenteral nutrition. II. Blood levels of vitamins A, D, and E.

This study represents the first attempt to evaluate the American Medical Association Nutrition Advisory Group (NAG) recommendations for intravenous vitamin A, D, and E dosages for infants and children. Patients studied included 18 preterm infants (group 1) and 26 term infants and children (group 2A) receiving total parenteral nutrition for 2 to 4 weeks and eight infants and children receiving total parenteral nutrition for 3 to 6 months (group 2B). Term gestation infants and children up to 11 years of age all received the same dosages (those that were recommended by the NAG for children weighing more than 10 kg). Preterm infants received 65% of these doses. In group 1, cord blood alpha-tocopherol levels were less than 0.22 mg/dL in seven preterm infants (reference value = 0.29 +/- 0.04), but mean levels increased to 1.65 +/- 0.17 mg/dL after four days of treatment. Eight infants consistently received additional vitamin E orally (80 to 150 mg daily), and their levels increased to 2.18 +/- 0.26 mg/dL by four days of study and to 3.49 +/- 0.57 mg/dL after 3 weeks. Oral supplementation in the preterm infants appeared to be unnecessary because intravenous vitamins alone maintained levels above 1.1 mg/dL. In group 2, alpha-tocopherol levels were maintained within the reference range. Patients receiving lipid emulsions containing substantial quantities of alpha-tocopherol had significantly higher blood levels than patients receiving lipid emulsions containing little alpha-tocopherol (P less than .01). Mean 25-OH vitamin D levels were maintained above or within the reference range in groups 2A and 2B.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗