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Biomedical subjects

D Harvey

Publications and source records attributed to D Harvey.

133 records · Page 8Linked to original sources
PubMedDate not supplied

Syntheses of haptens containing dioxaphosphorinan methoxyacetic acid linker arms for the production of antibodies to organophosphate pesticides.

Four generic heterobifunctional reagents, namely 2-(2-chloro-5-methyl-1,3,2-dioxaphosphorinan-5-yl)methoxyacetic acid methyl ester, p-sulfide, 2-(2-chloro-5-methyl-1,3,2-dioxaphosphorinan-5-yl)-methoxyacetic acid methyl ester, p-oxide, 2-(2-mercapto-5-methyl-1,3,2-dioxaphosphorinan-5-yl)-methoxyacetic acid bispotassium salt, p-sulfide-, and (2-methoxy-5-methyl-1,3,2-dioxaphosphorinan-5-yl)methoxyacetic acid, methyl ester, have been synthesized and used to prepare organophosphate, thiophosphate, and dithiophosphate haptens containing a functional carboxyl group which can be used to conjugate the haptens to proteins. These hapten-protein conjugates have been used as antigens for preparing polyclonal sera against all classes of organophosphate pesticides. The eight examples used protein-hapten conjugates of chlorpyrifos, parathion, diazinon, paraoxon, azinphos, dimethoate, demeton, and dichlorvos. These were all immunogenic and resulted in sera containing antibodies that recognized the corresponding parent pesticide with high specificity.

Acetates↗
PubMedDate not supplied

Quantitative histological changes in the small intestine of rats artificially reared on different milk substitutes.

Growth of the small intestine was studied in rats reared normally by their mothers (MR) or artificially reared (AR) by intragastric infusion of milk substitutes from postnatal day 5. Two milk substitutes were used: one high in carbohydrate and low in protein as compared with rats' milk (Messer) and the other closely resembling rats' milk in its composition (Auestad). Pups reared on these formulae are termed ARM and ARA, respectively. Pups were killed at 7, 12, and 20 days for quantitative histological measurements on transverse sections of duodenum and ileum. They included cross-sectional areas of muscle and of mucosa and submucosa combined (other tissue), internal and external perimeters, and length of longest villus profile. Artificial rearing affected mucosal and submucosal measures, but did not affect muscle. The effects depended on age, type of milk substitute, and site within the small intestine. There was a tendency for deficient growth of small intestine in the early stages of artificial rearing, especially in the ileum of ARA pups. Enhancement of growth as shown by cross-sectional area of mucosa and submucosa and by longest villus profile occurred later--by 12 days in the duodenum and by 20 days in the ileum of ARM pups. Enhanced growth was less evident in ARA rats, being apparent only in the duodenum, and not until 20 days were the cross-sectional area of mucosa and submucosa and the longest villus profile increased.

Animal Nutritional Physiological Phenomena↗
PubMedDate not supplied

Measurement of fetal plasma levels of glutathione S-transferase B1 as an indicator of damage to the liver caused by hypoxia in utero.

Glutathione S-transferase B1 (GST B1) concentration in blood and amniotic fluid from fetuses investigated for a variety of conditions including rhesus (Rh) allo-immunisation was assessed for its usefulness as a measure of liver damage caused by hypoxia in utero. The concentration in blood from the intrahepatic vein (IHV) was 10-fold higher than that from the placental cord insertion suggesting that parenchymal liver cells are damaged during blood sampling from the IHV. As a measure of hepatocellular impairment caused by intra-uterine hypoxia, levels were higher in frankly acidotic fetuses than in normally managed Rh fetuses. The degree of hypoxia required to trigger the release of GST B1 into the plasma remains unclear.

Amniocentesis↗