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Mark R Bruins

Publications and source records attributed to Mark R Bruins.

4 recordsLinked to original sources
PubMed2003

Characterization of a small plasmid (pMBCP) from bovine Pseudomonas pickettii that confers cadmium resistance.

This is the first report of isolation of Pseudomonas pickettii from a normal adult bovine duodenum. This organism was one of several bacteria isolated as part of a study to examine cadmium resistance genes (cad(r)) for use in generating transgenic plants to reclaim cadmium-contaminated soils in Kansas. P. pickettii containing a plasmid of 2.2kb (designated pMBCP) grew in Luria-Bertani broth and agar containing up to 800 microM of cadmium chloride and was resistant to 16 antibiotics. Curing the organism of plasmid revealed that antibiotic resistances were not plasmid-mediated. Low-level cadmium resistance was conferred by the plasmid because uncured organism grew significantly better (P<0.05) at 55 microM compared to cured organism. Both plasmid and chromosomal DNA were probed by DNA-DNA hybridization for the presence of known cadmium resistance genes (cadA, cadC, and cadD from Gram-positive (Staphylococcus aureus), but none were detected. The plasmid had one restriction site each for BamHI, PstI, SmaI, and XhoI; two sites each for HincII, SacI, and SphI; and multiple sites for AluI and XcmI. DNA sequence analyses of the cloned and original plasmids showed a GC content of greater than 60% and no homology to any published sequences in the GenBank, European Bioinformatics Institute, or Japanese Genome Net databases. The DNA sequence is contained in GenBank accession number AF144733. Thus, pMBCP offers low-level cadmium resistance to P. picketttii.

Animals↗
PubMed2002

Extraction of amphetamine and methamphetamine from urine specimens with Cerex Polycrom Clin II solid-phase extraction columns and the Speedisk 48 Pressure Processor.

Extraction of amphetamine and methamphetamine in urine was investigated using Cerex Polycrom Clin II solid-phase extraction columns and the Speedisk 48 Pressure Processor as a replacement for our liquid-liquid procedure. Linearity for urine standards extracted with the Cerex-Speedisk method ranged from 50 ng/mL for methamphetamine and from 150 ng/mL for amphetamine to 10,000 ng/mL for both. The mean recovery at the 500-ng/mL cutoff for three different lots of columns was 96.4% for AMP and 95.7% for MET. The mean of the within-run means for three batches was 495.4 ng/mL with a coefficient of variation (CV) of 1.2% or less for amphetamine and 496.4 ng/mL for methamphetamine with a CV of 1.7% or less. Thirty-six specimens containing amphetamine and the same number for methamphetamine were analyzed by both the Cerex-Speedisk and liquid-liquid methods. The correlation for specimens containing amphetamine gave an r2 of 0.9986 with a slope of 0.99; for methamphetamine, the r2 was 0.9997 with a slope of 0.98. The Cerex-Speedisk method cut extraction time in half, was less costly, and greatly reduced the volume of hazardous waste.

Amphetamine↗
PubMed2002

Drug-positive rates for the Army from fiscal years 1991 to 2000 and for the National Guard from Fiscal years 1997 to 2000.

This article examines the positive rate by drug for all urinalysis specimens tested by the U.S. Army from fiscal year 1991 (FY91) to FY00 and for the Army National Guard (NG) from FY97 to FY00. The average positive rate for the Army from FY91 to FY00 was 0.84%. In FY00, the Army rate reached a 10-year high of 1.04%. From FY97 to FY00, the NG positive rate declined from 3.4% to 2.16% but was significantly (p < 0.05) higher than the Army rate during the same period. Marijuana and cocaine are the most abused drugs for both the Army and NG. The positive rate for marijuana in the Army from FY91 to FY00 was 0.51%, and the cocaine rate was 0.19%. The NG marijuana-positive rate from FY97 to FY00 was 1.70%, and the cocaine rate was 0.51%. The positive rate for all other drugs of abuse tested was less than 0.3% for both the Army and NG during the same periods. The overall positive rate for the Army and NG are below those estimated (6.3%) in the civilian population.

Humans↗