Rheumatic Fever and Rheumatic Heart Disease in Barbados: Detection and Prophylaxis

The objectives of this study were to improve our methods of secondary prophylaxis of rheumatic fever and rheumatic heart disease in Barbados, to estimate the overall prevalence of these diseases and the relative load imposed by them on available health services, and to measure the yield, feasibility, and effectiveness of mass programmes for the detection and prophylactic management of rheumatic heart disease in schoolchildren.Improved methods of surveillance and follow-up resulted in 97% adherence to therapy by patients on prophylactic penicillin. Thirty-four children, 27 with a first attack, were admitted with acute rheumatic fever, representing a 7% occupancy of children''s medical beds during the 12-month period of the study. Out of a possible 3,942 schoolchildren aged 5-11 years, 3,882 (98%) were screened for rheumatic heart disease. Four cases (about 1 per 1,000) were discovered.     

The metabolites of cyclohexylamine in man and certain animals

1. [1-(14)C]Cyclohexylamine hydrochloride was synthesized and given orally or intraperitoneally to rats, rabbits and guinea pigs (dose 50-500mg/kg) and orally to humans (dose 25 or 200mg/person). The (14)C is excreted mainly in the urine, most of the excretion occurring in the first day after dosing. Only small amounts (1-7%) are found in the faeces. 2. In the rat, guinea pig and man, the amine is largely excreted unchanged, only 4-5% of the dose being metabolized in 24h in the rat and guinea pig and 1-2% in man. In the rabbit about two-thirds of the dose is excreted unchanged and about 30% is metabolized. 3. In the rat, five minor metabolites were found, namely cyclohexanol (0.05%), trans-3- (2.2%), cis-4- (1.7%), trans-4- (0.5%) and cis-3-aminocyclohexanol (0.1% of the dose in 24h). 4. In the rabbit, eight metabolites were identified, namely cyclohexanol (9.3%), trans-cyclohexane-1,2-diol (4.7%), cyclohexanone (0.2%), cyclohexylhydroxylamine (0.2%) and trans-3- (11.3%), cis-3- (0.6%), trans-4- (0.4%) and cis-4-aminocyclohexanol (0.2%). 5. In the guinea pig, six minor metabolites were found, namely cyclohexanol (0.5%), trans-cyclohexane-1,2-diol (2.5%) and trans-3- (1.2%), cis-3- (0.2%), trans-4- (0.2%) and cis-4-aminocyclohexanol (0.2%). 6. In man only two metabolites were definitely identified, namely cyclohexanol (0.2%) and trans-cyclohexane-1,2-diol (1.4% of the dose), but man had been given a smaller dose (3mg/kg) than the other species (50mg/kg). 7. The hydroxylated metabolites of cyclohexylamine were excreted in the urine in both free and conjugated forms. 8. Although cyclohexylamine is metabolized to only a minor extent, in rats the metabolism was mainly through hydroxylation of the cyclohexane ring, in man by deamination and in guinea pigs and rabbits by ring hydroxylation and deamination.     

The fate of cyclamate in man and other species

1. (14)C-labelled cyclamate has been administered to guinea pigs, rabbits, rats and humans. When given orally to these species on a cyclamate-free diet, cyclamate is excreted unchanged. In guinea pigs some 65% of a single dose is excreted in the urine and 30% in the faeces, the corresponding values for rats being 40 and 50%, for man, 30-50% and 40-60%, and for rabbits, 90 and 5%, the excretion being over a period of 2-3 days. 2. Cyclamate appears to be readily absorbed by rabbits but less readily by guinea pigs, rats and humans. 3. If these animals, including man, are placed on a diet containing cyclamate they develop the ability to convert orally administered cyclamate into cyclohexylamine and consequently into the metabolites of the latter. The extent to which this ability develops is variable, the development occurring more readily in rats than in rabbits or guinea pigs. In three human subjects, one developed the ability quite markedly in 10 days whereas two others did not in 30 days. Removal of the cyclamate from the diet caused a diminution in the ability to convert cyclamate into the amine. 4. In rats that had developed the ability to metabolize orally administered cyclamate, intraperitoneally injected cyclamate was not metabolized and was excreted unchanged in the urine. The biliary excretion of injected cyclamate in rats was very small, i.e. about 0.3% of the dose. 5. The ability of animals to convert cyclamate into cyclohexylamine appears to depend upon a continuous intake of cyclamate and on some factor in the gastrointestinal tract, probably the gut flora.     

Estimates of Incidence and Prevalence of Mongolism and of Congenital Heart Disease in British Columbia

There is a need for accurate ascertainment of incidence and prevalence rates of congenital anomalies. In British Columbia the Registry for Handicapped Children and Adults used in conjunction with vital records has proved a valuable source of information. Birth notifications alone cannot be relied upon for incidence data. It was found that seven times as many cases of congenital heart disease were registered subsequently as were reported at birth. The estimated minimal incidence rates of mongolism and congenital heart disease per 1000 live births were 1.46 and 4.75, respectively. The well-known association of maternal age with mongolism was confirmed. Twice as many babies with congenital heart disease (without mongolism) were born to mothers over 39 years of age as would be expected on the basis of the maternal age distribution for all live births in the population. Prevalence estimates of these two diseases compared favourably with other published estimates.     

Characterization of a polymorphism in the 3′ part of the chicken vitellogenin gene

Summary An allele giving rise to a polymorphism within the 3 part of the chicken vitellogenin gene was cloned, sequenced, and compared to the previously cloned allele. The polymorphism is formed by a perfect copy of 343 bp from intron 32 in tandem array with a perfect copy of 244 bp from intron 33; this 587-bp element is inserted in a head-to-tail arrangement in intron 33. We propose a mechanism in which an unequal crossing-over resulted in a vitellogenin gene with two exons 33, one of which was subsequently deleted. Thus, intron 33 was enlarged by the tandem repeats without affecting the protein-encoding sequence of the gene. At the boundaries of the repeated elements, two short direct repeats are found that resemble the recombination signals of immunoglobulin genes. They may have had a key role in the formation of the new allele.     

Oxidation products of pinene in the bark beetle,Dendroctonus frontalis

Southern pine beetles were collected as they emerged from infested pine bolts and exposed in Petri dishes to α- and β-pinene for 20 hr. Changes in the volatile contents of the beetles' hindguts were detected by gas chromatography, and previously unidentified components were characterized by mass, i.r., and n.m.r. spectroscopy. A prominent compound in hindguts of both sexes before and after treatment was identified as myrtenol, and a less conspicuous, male-specific compound proved to be myrtenal. Upon exposure to α-pinene, males produced cis- and trans-verbenol, and 4-methyl-2-pentanol was found in both sexes. Compounds present after treatment with β-pinene vapour were identified as trans-pinocarveol in both sexes, and pinocarvone in the males.     

Effect of neuraminidase on the chromatographic behaviour of eleven acid hydrolases from human liver and plasma.

1. The elution profiles of eleven acid hydrolases from human liver and plasma were directly compared using a system whereby a single salt gradient was simultaneously applied to two DEAE-cellulose chromatographic columns. 2. Plasma alpha-L-fucosidase, alpha-mannosidase, alpha-galactosidase and alpha-glucosidase isoenzymes were eluted at higher salt concentrations than the corresponding liver isoenzymes whereasbeta-N-acetylglucosaminidase, beta-galactosidase, beta-glucosidase, exo-1,4-beta-xylosidase and alpha-L-arabinofuranosidase isoenzymes were eluted at lower salt concentrations. The elution profiles of beta-glucuronidase and acid phosphatase weremore complex. 3. After incubation with neuraminidase most plasma hydrolases were eluted at lower salt concentrations, however the elution patterns of beta-glucosidase, beta-xylosidase and acid phosphatase were not altered. 4. Preincubation with neuraminidase had no effect on the elution profiles of six liver hydrolases whereas the major isoenzymes of alpha-mannosidase, beta-galactosidase and alpha-L-arabinofuranosidase were eluted at markedly lower salt concentrations. Liver alpha-fucosidase and alpha-galactosidase were eluted at slightly lower salt concentrations afterincubation with neuraminidase. 5. The results are discussed in relation to thepathogenesis of Mucolipidosis II (I-cell disease), and the synthesis and packaging of lysosomal enzymes.