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J E Gallagher

Publications and source records attributed to J E Gallagher.

61 records · Page 4Linked to original sources
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Diazepam versus midazolam for colonoscopy: a prospective evaluation of predicted versus actual dosing requirements.

We performed a prospective, randomized, double-blind study to evaluate the efficacy of the currently recommended low doses of midazolam for conscious sedation compared with diazepam for colonoscopy. Each agent was administered in a fixed ratio dose in combination with meperidine, and titrated incrementally to allow for adequate sedation prior to initiating and during the procedure. The currently recommended starting dose of midazolam (0.03 mg/kg) proved to be very appropriate for pre-medication. In contrast, the currently recommended starting dose of diazepam (0.10 mg/kg) proved excessive in 21% of patients (especially in those aged > 65). The low initial and incremental doses of midazolam compared favorably with diazepam in all efficacy parameters studied and exceeded diazepam in post-procedure amnesia scores (p = 0.01). Moreover, the sedative effects of midazolam at these lower doses were not lost despite long duration procedures (> 40 min). We conclude that midazolam, given in small incremental doses, in combination with meperidine, produces effective conscious sedation for colonoscopy and exceeds diazepam in its amnestic effect.

Adult↗
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Separation of 32P-postlabeled DNA adducts of polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons by HPLC.

The 32P-postlabeling assay, thin-layer chromatography, and reverse-phase high-pressure liquid chromatography (HPLC) were used to separate DNA adducts formed from 10 polycyclic aromatic hydrocarbons (PAHs) and 6 nitrated polycyclic aromatic hydrocarbons (NO2-PAHs). The PAHs included benzo[j]fluoranthene, benzo[k]fluoranthene, indeno[1,2,3-cd]pyrene, benzo[a]pyrene, chrysene, 6-methylchrysene, 5-methylchrysene, and benz[a]anthracene. The NO2-PAHs included 1-nitropyrene, 2-nitrofluoranthene, 3-nitrofluoranthene, 1,6-dinitropyrene, 1,3-dinitropyrene, and 1,8-dinitropyrene. Separation of seven of the major PAH-DNA adducts was achieved by an initial PAH HPLC gradient system. The major NO2-PAH-DNA adducts were not all separated from each other using the initial PAH HPLC gradient but were clearly separated from the PAH-DNA adducts. A second NO2-PAH HPLC gradient system was developed to separate NO2-PAH-DNA adducts following one-dimensional TLC and HPLC analysis. HPLC profiles of NO2-PAH-DNA adducts were compared using both adduct enhancement versions of the 32P-postlabeling assay to evaluate the use of this technique on HPLC to screen for the presence of NO2-PAH-DNA adducts. To demonstrate the application of these separation methods to a complex mixture of DNA adducts, the chromatographic mobilities of the 32P-postlabeled DNA adduct standards (PAHs and NO2-PAHs) were compared with those produced by a complex mixture of polycyclic organic matter (POM) extracted from diesel emission particles. The diesel-derived adducts did not elute with the identical retention time of any of the PAH or NO2-PAH standards used in this study. HPLC analyses of the NO2-PAH-derived adducts (butanol extracted) revealed the presence of multiple DNA adducts.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
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Scanning electron and light microscopy of selected avian strains of Mycoplasma iowae.

The morphology of six strains of Mycoplasma iowae was studied at various stages of growth by scanning electron and light microscopy. The six strains, which formerly represented avian mycoplasmal serotypes I, J, K, N, Q, and R, produced filaments and branching filaments, sometimes with centrally or terminally located bulbous swellings. During cell division, the filaments appeared to develop into chains of coccal, coccobacillary, and elongated cells. Mycoplasmas that appeared as chains of cocci under light microscopy were often observed as coccobacillary or fusiform when viewed with scanning electron microscopy. The morphology of single or paired cells of all strains included cocci, rods, coccobacilli, and pleomorphic forms. Fusiform and teardrop-shaped cells with bleb-like structures were also observed. Some cells of all strains deteriorated by the latter growth stages, forming clumps of flattened irregular-shaped cells, sometimes intertwined with fragmented filaments. The formation of filaments, branching filaments, and the other cell morphology indicated that the six strains of M. iowae were similar in morphology and growth characteristics.

Animals↗
PubMedDate not supplied

32P-postlabeling analysis of DNA adducts in human sperm cells from smokers and nonsmokers.

To determine the feasibility of using human sperm cells for DNA 32P-postlabeling analyses, and to evaluate the baseline level and the possible presence of smoking-related DNA adducts in these cells, sperm DNA was isolated from specimens obtained from 12 heavy smokers, 12 light smokers, and 12 nonsmokers. Background levels of radioactivity were minimized by using magnet transfer of 32P-labeled mononucleotides to new polyethyleneimine cellulose plates. Compared with placental tissues, few adducts were observed. Diffuse radioactivity observed in some of the autoradiograms was minimally above background but the level of radioactivity expressed as putative adducts/nucleotide was not related to smoking status. It was not clear, in some cases, whether this radioactivity was associated with chemically bound adducts or was from nonspecifically bound chemicals, radiolabeled enzymes, or other proteins. One major discrete DNA adduct of unknown chemical structure was detected in three of the 36 samples analyzed (one nonsmoker and two smokers). Based on the level of radioactivity associated with various dilutions of a benzo(a)pyrene-derived adduct, our limit of sensitivity was at least 1.2 adducts/10(9) nucleotides. Our study emphasizes the need to more clearly define the significance of background radioactivity associated with DNA adduct maps where the measured adduct levels approximate detection limits defined by visual observance of adduct spots. This point is particularly relevant given that the 32P-postlabeling procedures rely, in part, on visual verification of the presence of DNA adducts.

Adult↗