Health and cultural factors associated with enrolment in basic education: a study in rural Ghana.

This inter-disciplinary study compares the health status of school-age children in Ghana, both enrolled and non-enrolled, and examines these results within a wider socio-economic and socio-cultural context including kinship and livelihood. Children matched for age and sex who were not enrolled in Primary School were significantly shorter and more stunted than enrolled children were, and 70% of all Primary school-age children were anaemic. Young children from farming communities were significantly more undernourished than children from fishing communities. Adolescent non-enrolled boys were more heavily infected with Schistosoma haematobium, and were more likely to be anaemic than enrolled adolescent boys. The data indicate how health and health related factors may influence and affect enrolment and how socio-economic indicators, livelihood, and kinship may also constrain enrolment and, in turn, affect child health. This study sheds light on the complex factors that may influence enrolment in education and provides novel data on the similarities and differences between the health of enrolled and non-enrolled children in rural Ghana.

Steady-state response of a charcoal bed to radon in flowing air with water vapor.

Previously we have developed a mathematical model of radon adsorption in active air with water vapor on small U.S. Environmental Protection Agency charcoal canisters that are used for environmental measurements of radon. The purpose of this paper is to extend this mathematical model to describe the adsorption of radon by large charcoal beds with radon-laden air flowing through them. The resulting model equations are solved analytically to predict the steady-state adsorption of radon by such beds.

Isolation and identification of major metabolites of tixocortol pivalate in human urine.

The metabolism of tixocortol pivalate (PIVALONE), an anti-inflammatory steroid without systemic glucocorticoid effects, has been investigated in man. The analysis was conducted using urine samples collected from two volunteers who had received a 2-g oral dose of 14C-tixocortol pivalate as an oral suspension. Metabolites were purified and isolated from urine by normal phase HPLC, and structural identification was achieved by desorption chemical ionization/NH3 and electron impact/direct line introduction mass spectrometry. Unchanged tixocortol pivalate was not detected in urine; all metabolites were sulfo- and glucurono-conjugates. Metabolites were identified in the neutral steroid fraction obtained after hydrolysis of conjugates. Metabolic transformations in common with cortisol were reduction of the 3-keto, delta 4 system, reduction of the C-20 carbonyl group, oxidation of the C-11 alcohol, and cleavage of the side chain at C-17. Specific metabolic pathways involving the C-21 thiol ester function were transformations into methylthio, methylsulfinyl and methylsulfonyl derivatives, and a reductive cleavage of the C-21-S bond leading to 21-methyl structures. Since none of these metabolites had binding affinity for glucocorticoid receptors in vitro, fast and extensive transformation of tixocortol pivalate into inactive metabolites provides an explanation for the large dissociation between the topical and systemic activities of this drug.

The pharmacological activity of the fatty acid conjugate 11-palmitoyloxy-delta 9-tetrahydrocannabinol.

A long-retained cannabinoid metabolite has been detected in rat tissue after intravenous administration of delta 9-tetrahydrocannabinol (THC) and has been identified as a fatty acid conjugate of psychoactive 11-hydroxy-delta 9-tetrahydrocannabinol (11-OH-delta 9-THC) and palmitic acid. The objective of these studies was to determine if this compound, 11-palmitoyloxy-delta 9-tetrahydrocannabinol (11-palm-delta 9-THC) is pharmacologically active. Intravenously injected 11-palm-delta 9-THC decreased thermal sensitivity and induced catalepsy in rats, responses similar to those produced by 11-OH-delta 9-THC, but less pronounced and more delayed. To further characterize the response, animals were intracisternally injected with 11-OH-delta 9-THC or 11-palm-delta 9-THC. Catalepsy and decreased thermal sensitivity were seen in the 11-OH-delta 9-THC and 11-palm-delta 9-THC groups, and again, 11-OH-delta 9-THC appeared to be the more potent of the two cannabinoids. In contrast to the intravenous study, 11-palm-delta 9-THC-induced effects were seen soon after treatment and appeared to be fully developed by the first test time (15 min). The intracisternal results suggest that 11-palm-delta 9-THC itself is active; however, since it is known that the fatty acid conjugate is hydrolyzed in vivo to 11-OH-delta 9-THC in the rat, the possibility remains that the effects of 11-palm-delta 9-THC are due to metabolic conversion to 11-OH-delta 9-THC.

Fatty-acid conjugation with cyclamate metabolites as a possible mechanism for ultimate retention.

In an in vitro rat-liver microsomal system fortified with coenzyme. A palmitic acid was found to conjugate at the nitrogen moiety of the cyclamate metabolite cyclohexylamine (CHA) and at both the nitrogen and oxygen moieties of its metabolite N-cyclohexylhydroxylamine (CHHA). The fatty acid was preferentially conjugated at or preferentially retained to the nitrogen moiety of CHHA. Stearic acid was also shown to conjugate with CHA. Amines may thus be another class of compounds that, like hydroxylated compounds, are retained in vivo as fatty-acid conjugates in lipid-containing tissues of animals.

In vitro conjugation of the trichloroethylene metabolite trichloroethanol to a fatty acid.

Trichloroethanol (TCA), a major metabolite of the known carcinogen trichloroethylene (TCE), was shown to conjugate to palmitic acid in an in vitro rat liver coenzyme A fortified microsomal system. This conjugation of a fatty acid to one of its major metabolites may be the mechanism by which TCE is retained in the body and ultimately exerts its toxic or carcinogenic effect.

Conjugation of fatty acids to DDT in the rat: possible mechanism for retention.

Palmitic, stearic, oleic, and linoleic fatty acid conjugates of DDT were retained in vivo in livers and spleens of male and female rats given chronic i.p. injections of DDT. These DDT fatty acid conjugates could also be produced in vitro in a rat liver coenzyme A fortified microsomal system using the DDT hydroxylated metabolite DDOH as the substrate. The phenomenon of fatty acid conjugation to DDT may be a mechanism by which it is retained in the body and ultimately exerts its toxic effect.

Long-retained metabolites of delta9- and delta8-tetrahydrocannabinols identified as novel fatty acid conjugates.

Long-retained metabolites of delta9-tetrahydrocannabinol (delta9-THC) and delta8-tetrahydrocannabinol (delta8-THC) previously detected in the liver, spleen, fat, and bone marrow of the rat after I.V. or I.P. injections of 14C-delta8-THC or 14C-delta9-THC, have been identified as fatty acid conjugates of 11-hydroxy-delta9-THC and 11-hydroxy-delta8-THC. Characterization of the metabolites was facilitated by their large-scale in vitro production from 11-hydroxy-delta9-THC and 11-hydroxy-delta8-THC with a rat-liver microsomal enzyme system. Conjugation of long-chain fatty acids to drugs or their hydroxylated metabolites may have considerable biological significance.

Metabolite of (-)-trans-delta 8-tetrahydrocannabinol: identification and synthesis.

The major metabolite of (-)-trans-Delta(8)-tetrahydrocannabinol observed in vivo and formed by hepatic microsomes in vitro is 11-hydroxy-trans-Delta(8)-tetrahydrocannabinol. The metabolite was identified spectroscopically and was synthesized from trans-Delta(8)-tetrahydrocannabinol. In tests with rats, the metabolite produced behavioral effects similar to those imparted by Delta(8)- and Delta(9)-tetrahydrocannabinol.