Biomedical subjects

D W Fitzpatrick

Publications and source records attributed to D W Fitzpatrick.

22 records · Page 2Linked to original sources

PubMed1988

Effect of T-2 toxin on brain biogenic monoamines in rats and chickens.

Two experiments were conducted to determine the effect of T-2 toxin on brain biogenic monoamines and their metabolites. Male rats (180 g) and cockerels (28 day, 300 g) were orally dosed with T-2 toxin at 2.5 mg kg-1 body weight. In the first experiment, whole brains were collected 2, 6, 12, 24 and 48 h postdosing and analyzed for monoamines by high performance liquid chromatography with electro-chemical detection. T-2 toxin did not influence whole brain concentrations of monoamines in either species. In the second experiment, brains were collected 24 h postdosing, dissected into five brain regions, and analyzed for monoamines. T-2 toxin treatment resulted in increased serotonin and 5-hydroxy-3-indoleacetic acid in all brain regions of the rat. However, this was not seen in poultry where T-2 toxin treatment resulted in an increase in 5-hydroxy-3-indoleacetic acid, no alteration in serotonin concentration and a decrease in regional norepinephrine and dopamine concentrations. These results suggest that T-2 toxin influences brain biogenic amine metabolism and that there is an intraspecies difference in the central effects of this mycotoxin.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1982

Carnosine, histidine, and wound healing.

The relationships among carnosine, histidine, and wound healing were examined in rats fed either 100% or 50% of the reported histidine required for growth. Animals fed the adequate amount of histidine grew more rapidly and more efficiently than did animals on the low-histidine diet. When the rats reached the experimental weight range of 165 to 180 gm, they were anesthetized and wounded with back skin incision; a polyvinylchloride sponge was implanted under the skin before closure of the wound. Seven days after wounding, the histidine-sufficient animals had greater regenerative skin-breaking strength, collagen deposition, and tissue concentrations of free histidine and carnosine. Histidine and carnosine treatment (1 mg/100 gm body weight/day intraperitoneally) for 7 days after wounding increased tissue free-histidine concentrations and brought skin-breaking strength and collagen deposition up to "normal" in the animals on the low-histidine diet but did not further improve healing in the histidine-sufficient animals. Treatment with carnosine was similar, but slightly better than treatment with histidine. The results suggest an interaction between carnosine and stress and implicate carnosine as a histidine reserve in relation to histamine synthesis during trauma.

Animals↗

PubMed1982

Histamine synthesis, imidazole dipeptides, and wound healing.

The relationships among anserine (beta-alanyl-1-methyl-L-histidine), carnosine (beta-alanyl-L-histidine), free histidine, and histamine metabolism were examined in rats wounded by dorsal skin incision. Following wounding, rats were treated with either a histamine liberator (compound 48/80) or a histidine decarboxylase inhibitor (4-imidazolyl-3-amino-2-butanone). The liberator greatly enhanced wounded skin-breaking strength and collagen deposition at the wound site, while the histidine decarboxylase inhibitor reduced skin-breaking strength and collagen deposition. In the second experiment of this study, histamine or histidine treatment was shown to prevent trauma-induced reductions of tissue carnosine but was less effective in ameliorating tissue anserine loss. The results illustrate an interaction between imidazole dipeptides and stress and suggest that carnosine acts as a histidine reserve in relation to histamine synthesis during trauma.

Animals↗

PubMedDate not supplied

Rapid, sensitive liquid chromatographic method for determination of zearalenone and alpha- and beta-zearalenol in wheat.

A rapid, sensitive liquid chromatographic (LC) method is described for quantitative determination of zearalenone and alpha- and beta-zearalenol in wheat. The procedure incorporates an internal standard, zearalenone oxime, to facilitate quantitation and automated analysis. A sample, buffered with pH 7.8 phosphate, is extracted with water-ethanol-chloroform (2 + 50 + 75) and cleaned up. The final residue is dissolved in LC mobile phase and injected onto a reverse phase RP-18 column under the following conditions: water-methanol-acetonitrile (5 + 3 + 2) mobile phase; fluorescence (excitation wavelength 236 nm, 418 nm cut-off emission filter) and UV (254 nm, range 0.0025 AU) detectors. The limit of detectability (twice background) is 0.5 ng for zearalenone and alpha-zearalenol standards on the fluorescence detector and 4 ng for beta-zearalenol on the UV detector, which is equivalent to 20 micrograms zearalenone and 20 micrograms alpha-zearalenol/kg, and 160 micrograms beta-zearalenol/kg feed. Standard curves are linear over the range 0-35 ng zearalenone and alpha-zearalenol on the fluorescence detector and 0-50 ng beta-zearalenol on the UV detector. Recoveries of all compounds are 87.5-101% in the range 0.1-3.0 mg/kg (ppm).

Chromatography, Liquid↗