Metabolism of D-[3H]threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, an inhibitor of glucosylceramide synthesis, and the synergistic action of an inhibitor of microsomal monooxygenase

D-Threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) is an effective inhibitor of the glucosyltransferase that makes glucosylceramide. Virtually all of the hundreds of naturally occurring glycolipids are formed from this primary glycolipid, so the inhibitor acts to lower their concentrations by the process of attrition (hydrolytic catabolism). Trials with mice carrying ascites carcinoma cells showed that PDMP could produce a permanent cure in some of the animals and marked prolongation of life in the others (Inokuchi, J., I. Mason, and N.S. Radin. 1987. Cancer Lett. 38: 23-30). In order to maximize the effect, we studied the metabolism of PDMP by labeling it with [3H] on carbon one, using a labeling method that discriminated against the unwanted erythro-isomer. The active enantiomer of the inhibitor (D-) was isolated by chromatography of the camphanate esters, followed by methanolytic cleavage. Examination of the fate of the labeled drug after a single injection showed that it was very rapidly converted to several polar products that were rapidly excreted. The drug penetrated all of the organs readily and a small portion was oxidized at the C-1 position to yield 3H2O. From these findings it appeared likely that the amine is attacked by a mixed function oxidase based on cytochrome P450. This conclusion was confirmed by showing that the tissue levels of PDMP could be greatly elevated, for a much longer time, when the mice were pretreated with piperonyl butoxide or cimetidine. The amount of conversion to polar metabolites was substantially reduced and tissue levels of PDMP were maintained much longer. Analysis of mice injected with one or both drugs showed that piperonyl butoxide augmented the effects of PDMP on ceramide, glucosylceramide, and dihexosylceramide levels, as well as on the activity of glucosylceramide synthase. It is suggested that piperonyl butoxide be used as an adjuvant for the many useful drugs that are inactivated by the P450 system.

Congenital monomelic hypertrophy with progressive myopathy

We describe a patient with congenital monomelic hypertrophy who later developed progressive footdrop due to a degenerative myopathy. The clinical, electrophysiologic, and pathologic features of the case are described and compared with those of a previously reported case.

Occupational health and the environment in an urban slum in India

The Indo-Dutch Environmental & Sanitary Engineering Project under the Ganga action Plan in Kanpur and Mirzapur is being executed within the Indo-Dutch bilateral development cooperation framework. The project aims to integrate physical, social and health related improvements. It is expected that the development approach and methodology can be replicated in other urban settlements in India. The project is being supplemented by a training and institutional strengthening programme to facilitate the transfer of new technologies and improvement of operation and maintenance of the new facilities. The project is also aimed at the improvement of the living conditions of the population, by installing drinking water and drainage systems. A socio-economic unit in the project supports the technical interventions by enhancing the community to participate in project activities. The Occupational Health Programme in Jajmau, an industrial slum of Kanpur, aims to improve the working conditions of tannery workers. Four hundred and ninety-seven tannery workers and 80 employees not engaged in leather work, from 20 tanneries, were interviewed and underwent physical examination. The mean age of tannery workers was 32 years, about half of them recently migrated to Kanpur. The majority of the workers are illiterate, have temporary jobs and 85% have a monthly income between 300 and 600 Rs. Occupational morbidity was 28.2%. Regular meetings with tannery owners, the training of tannery workers in first aid, and support for the installation of safety and health councils in tanneries are the main programme activities.(ABSTRACT TRUNCATED AT 250 WORDS)

Normal newborns: special problems during the first three days of life

Most newborns are admitted and managed in level 1 nurseries. Hypoglycemia, polycythemia, and jitteriness are three common clinical problems of these newborns, for which the family physician may request pediatric consultation. The authors discuss the definition, incidence, etiologies, clinical features, and the current diagnostic and treatment approach of these problems.

Effect of latent iron deficiency on the levels of iron, calcium, zinc, copper, manganese, cadmium and lead in liver, kidney and spleen of growing rats

Feeding a marginally low iron content diet (18-20 mg iron/kg diet) to weaned (21-day-old) rats for 8 weeks produced a significant decrease in liver non-heme iron (66%, p less than 0.001) but no change in blood hemoglobin. Total iron contents of liver (56%, p less than 0.01), spleen (20%, p less than 0.05), and kidney (19%, p less than 0.05) were also found to decrease along with increased zinc, copper, calcium, manganese lead and cadmium in various organs. The magnitude of alteration of a metal was different in different organs. However, liver was found to be the most affected organ. Two weeks of rehabilitation with iron-sufficient diet (390 mg iron/kg diet) normalized these altered levels.

Heat-stable protein that stimulates acid alpha-glucosidase

A hot-water extract of bovine spleen and guinea pig liver exhibited the ability to enhance acid alpha-glucosidase activity, with methylumbelliferyl alpha-glucoside, glycogen or maltose as substrate. The level of activator required for maximal stabilization was similar for all three substrates, indicating direct action on the enzyme rather than on substrate. The stimulator was partially purified by chromatography with gel-permeation (apparent Mr 20,000-24,000), ion-exchange and C4 reverse-phase columns. It was retained by a narrow-pore dialysis tubing and destroyed by treatment with Pronase, and is presumably a protein. The stimulating protein protected the enzyme against denaturation by heat or incubation with a buffer of high ionic strength in the absence of substrate. RNA inhibited the enzyme, and the activator protein was able to counteract the effect. Activating material was found in a variety of mouse and rat tissues, as well as human urine.

Effect of latent iron deficiency on metal levels of rat brain regions

Seven different metals (iron, copper, zinc, calcium, manganese, lead, and cadmium) were studied in eight different brain regions (cerebral cortex, cerebellum, corpus striatum, hypothalamus, hippocampus, midbrain, medulla oblongata, and pons) of weaned rats (21-d-old) maintained on an iron-deficient (18-20 mg iron/kg) diet for 8 wk. Iron was found to decrease in all the brain regions, except medulla oblongata and pons, in comparison to their respective levels in control rats, receiving an iron-sufficient (390 mg iron/kg) diet. Brain regions showed different susceptibility toward iron deficiency-induced alterations in the levels of various metals, such as zinc, was found to increase in hippocampus (19%, p less than 0.05) and midbrain (16%, p less than 0.05), copper in cerebral cortex (18%, p less than 0.05) and corpus striatum (16% p less than 0.05), calcium in corpus striatum (22%, p less than 0.01) and hypothalamus (17%, p less than 0.02), and manganese in hypothalamus (18%, p less than 0.05) only. Toxic metals lead and cadmium also increased in cerebellum (19%, p less than 0.05) and hippocampus (17%, p less than 0.05) regions, respectively. Apart from these changes, liver (64%, p less than 0.001) and brain (19%, p less than 0.01) nonheme iron contents were found to decrease significantly, but body, liver, and brain weights, packed cell volume, and hemoglobin content remained unaltered in these experimental rats. Rehabilitation of iron-deficient rats with an iron-sufficient diet for 2 wk recovered the values of zinc in both the hippocampus and mid-brain regions and calcium in the hypothalamus region only. Liver nonheme iron improved significantly; however, no remarkable effect was noticed in brain nonheme iron following rehabilitation. It may be concluded that latent iron deficiency produced alterations in various metal levels in different brain regions, and corpus striatum was found to be the most vulnerable region for such changes. It is also evident that brain regions were resistant for any recovery in their altered metallic levels in response to rehabilitation for 2 wk.

Latent iron deficiency alters gamma-aminobutyric acid and glutamate metabolism in rat brain

A diet containing 18-20 mg iron/kg to young weaned rats for 8 weeks altered the metabolism of gamma-aminobutyric acid and glutamate in the central nervous system without affecting blood hemoglobin. Subsequent rehabilitation with 390 mg iron/kg diet for 2 weeks normalized these changes.

Effect of latent iron deficiency on 5-hydroxytryptamine metabolism in rat brain

Eight weeks of latent iron deficiency in weaned rats maintained on an experimental low iron content diet (18-20 mg/kg) did not significantly alter the packed cell volume and hemoglobin concentration; however, the hepatic and brain nonheme iron contents decreased by 66% and 21% (p less than 0.001), respectively. The tryptophan concentration decreased by 31% and 34% in liver and brain, respectively, in rats on experimental diet (p less than 0.01). The brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid contents were reduced by 21% and 23% (p less than 0.01 and p less than 0.02), respectively. However, in the brain, weight, protein, DNA, and the activities of monoamine oxidase, aldehyde dehydrogenase, and liver tryptophan oxygenase were found to remain unaltered. When rehabilitated with a diet containing 390 mg/kg iron, rats previously maintained on the experimental diet for 2 weeks showed partial recovery in tryptophan levels both in liver and brain. However, brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels remained unaltered. The hepatic iron content improved without any change in brain iron content. The latent iron deficiency produced significant alterations in the metabolism of 5-hydroxytryptamine and brain iron content that could not be recovered 2 weeks after the iron rehabilitation.

Ultrasonic and thermodynamic studies of tetracyclines in solutions

The ultrasonic velocity, U, density, and viscosity of aqueous and non-aqueous (water + dioxan) solutions of tetracycline hydrochloride and chlorotetracycline have been measured at two different temperatures. Partial molal volumes, [Formula: see text] partial molal compressibility, [Formula: see text], Vand's interaction coefficients, Q and C, and thermodynamic activation parameters ΔG*, ΔS*, and ΔH* of these solutions have been computed from the ultrasonic velocity, density, and viscosity data. The results are interpreted in terms of solute–solvent interaction.

Colloid osmotic pressure in infants with hyaline membrane disease

Colloid osmotic pressure (COP) was measured serially in 81 critically ill neonates with hyaline membrane disease (HMD) during the first five days of life, and these changes were correlated with the birth weight, gestational age, serum protein level, clinical status, and outcome. Colloid osmotic pressure correlated better with the total protein level (n = 81; r = 0.54) than with birth weight (r = 0.23) and gestational age (r = 0.31; n = 81). Seventy-one of 81 neonates survived. Among the survivors, COP increased significantly by day 5, whereas changes in the total protein level were not significant during the same period. Colloid osmotic pressure decreased significantly in nine of ten nonsurvivors (mean +/- SE, 11 +/- 0.5 to 8 +/- 0.55 mm Hg), whereas the total protein level did not show a similar change. Thus, COP cannot be accurately predicted by measuring serum protein during acute illness. Serial measurement of COP was a better prognostic indicator than the total protein level in infants with HMD.

Simultaneous tissue pH and transcutaneous carbon dioxide monitoring in critically ill neonates

Clinical usefulness and factors affecting transcutaneous CO2 (PtcCO2) monitoring were studied in 22 critically ill neonates. In 10 of 22 infants, both tissue pH (pHt) and PtcCO2 were monitored simultaneously using Roche pHt and CO2 electrodes. Arterial blood gases were obtained from umbilical artery catheter. The effect of variations in blood pressure, oxygenation, arterial pH (pHa) pHt, and medications on PtcCO2 were studied. There was a linear correlation between pHt and pHa (n = 108, r = 0.85, slope 1.08), PtcCo2 and PaCO2 (n = 188, r = 0.85, slope 1.49). The pHt changes correlated better with PtcCO2 than with arterial CO2 (r = 0.78, slope 1.35). The major factors affecting the PtcCO2 relationship were (a) hypoxia and (b) acidosis. When PaO2 less than 40 torr, PtcCO2 correlated poorly to PaCO2 (n = 23, r = 0.48, slope 0.72) whereas, during normoxia (PaO2 greater than 40 torr), it correlated well, r = 0.85, slope 1.51 similarly. When pHt was greater than 7.30, PtcCO2 correlated better with PaCO2 (r = 0.88, slope 1.37) than during tissue acidosis (r = 0.71, slope 1.51). Mean blood pressure down to 30 mm Hg and administration of dopamine and tolazoline did not affect the PtcCO2 to PaCO2 relationship (n = 69, r = 0.86, slope 1.6). Clinically, both continuous pHt and PtcCO2 were found to be very useful in the management of critically ill neonates.

Infantile overnutrition in the first year of life: a field study in Dudley, Worcestershire

A survey of feeding patterns and nutrient intake in relation to the growth of 300 normal infants up to 1 year of age in Dudley, Worcestershire, highlights a problem of overnutrition in the group; 50 (16.7%) were found to be suffering from infantile obesity and a further 83 (27.7%) were overweight.During the first three months of life the daily energy intakes of 136 cal/kg body weight for boys and 149 for girls were markedly greater than the level of 120/kg recommended by the Department of Health and Social Security. This coincided with the early addition of solid foods to a full milk intake. 119 babies (39.7%) were offered solids before they were 4 weeks old and 280 (93.3%) before 13 weeks of age. Some babies had solids from the first week after birth. Protein intake was persistently high throughout the first year, and the mean intake of 32.7 g/day was much greater than the intake of 20 g for infants aged up to 1 year recommended by the Department of Health. Standards for fat and carbohydrate intake are not available but in comparison with the levels reported in breast-fed babies intake of fat and carbohydrate was high in the first three months and came closer to the desired level for the former and remained slightly high for the latter in the subsequent age quarters.The relation of childhood and subsequent adult obesity to infant feeding patterns is not yet clear, but there is a high correlation between obese parents and obese and overweight babies; had these babies not been overfed the condition might have been prevented.