Clerodane-type diterpenes from the seed pods of Hymenaea courbaril var. stilbocarpa.

Three known and two new diterpenes were isolated from the ethyl acetate extract of Hymenaea courbaril var. stilbocarpa seed pods. One of the compounds was elucidated as (5R*,8S*,9S*,10R*)-cleroda-3,13E-dien-15-oic acid and the other was elucidated, after treatment with diazomethane, as methyl (5S*,8S*,9S*,10R*)-cleroda-3,13E-dien-15-oate. The known diterpenes were identified as (-)-ozic acid, (-)-isoozic acid and (-)-kovalenic acid which were characterized as their methyl ester derivatives.

The ecological and taxonomic importance of flower volatiles of Clusia species (Guttiferae).

The chemical composition of floral volatiles of sixteen species of Clusia (Guttiferae) belonging to four different taxonomic sections of the genus was investigated. The volatiles were extracted from fresh petals by microhydrodistillation and analysed by GC/MS. The composition of the volatiles was in part, but not always, related to the taxonomic position of the species, and to a minor extent to the type of pollinator observed on the flowers as revealed by clustering analysis. The composition of the volatile components of female and male flowers belonging to the same species (C. grandiflora, C. lanceolata, C. paralicola, C. parviflora and C. spiritu-sanctensis) was found to be almost identical. Field bioassays showed the petal extracts to be attractive to pollinating bees.

[Variations of structure and of flora of the "carrasco" vegetation of the Ibiapaba plateau, state of Cearsá, Brazil]. / Variações estruturais e florísticas do carrasco no planalto da ibiapaba, estado do Ceará.

"Carrasco" is a closed, tall-shrubby, xerophilous vegetation on Quartz Sand soils between altitudes of 700 and 900 m on Ibiapaba and Araripe plateaus in the Brazilian semi-arid domain. As it is still very poorly known, this paper aims to describe the structure and composition of the woody community and its spatial variation in relation to the soil. One-hundred 10 x 10 m plots were located by pairs of random numbers in a coordinate system at the locality of Jaburuna (3 degrees 54'34"S, 40 degrees 59'24"W, about 830 m altitude), municipality of Ubajara, north Ibiapaba. All woody plants with a minimum stem diameter of 3 cm at ground level had their vertical height (not for climbers) and stem perimeter recorded. A soil extract from 0-50 cm depth was taken at the centre of each plot. Published surveys of other carrasco areas on the south Ibiapaba were considered for comparison. The community structure showed great dominance concentration, the most abundant species (Acacia langsdorffii, Piptadenia moniliformis, Thiloa glaucocarpa) varied between surveys. At Jaburuna 81% of all sampled plants were shrubs, 14% trees (the most with less than 10 cm of trunk diameter and 6 m height), and 5% climbers. Canberra distances and Jaccard's Indices were calculated from a primary matrix of 87 species (with 5 or more individuals) and 175 plots. Several methods of cluster analysis were employed, all showed great floristic variation from place to place. A matrix of soil physical and chemical variates per plot was constructed, and the canonical correspondence analysis was applied to both primary and soil matrices. Lower pH and higher sum of bases (e. g. Brunfelsia cuneifolia, Neojeobertia candoleana), higher content of gross sand (e. g. Acacia glomerosa, Aspidosperma subincanumn) and higher content of fine sand (e. g. Aspidosperma discolor, Hymenaea velutina) were the main variates separating species. The floristic richness at Jaburuna was of 74 species, and the surveys showed no difference in Shannon's diversity, which varied from 2.87 to 3.16 nats/individual.

Pollinators of Oxypetalum (Asclepiadaceae) in southeastern Brazil.

Floral visitors of seven species of Oxypetalum were registered in Viçosa, State of Minas Gerais. O. appendiculatum, O. banksii subsp, banksii, O. alpinumn var. alpinum and O. pachyglossum are pollinated by wasps, being Polybia ignobilis (Vespidae) a pollinator of these four species. It seems that P ignobilis promotes interspecific pollinations mainly between O. alpinum var. alpinum and O. pachyglossum, two species with very similar floral morphology. O. jacobinae, O. mexiae and O. subriparium are pollinated by bees. Wasps and bees carry one, two, three or several pollinaria in the mouthparts. O. mexiae, an endemic species in Viçosa, seems to present reproductive limitations, since its flowers are seldom visited.

Estudio prospectivo clínico e inmunológico de la vacuna antisarampionosa a virus vivo / Clinical and immunological prospective study of the measles live virus vaccine

Los autores presentan los resultados de su experiencia obtenida en un núcleo de 111 niños de un Asilo, en quienes aplicaron una vacuna contra el sarampión (a virus vivo atenuado más Gamma Globulina). Efectuando el dosaje de anticuerpos antes de dicha vacunación y 68 días después de la misma, comprobaron un franco ascenso de los mismos. Pero el hecho más interesante fue la casual contraprueba clínica, ya que al poco tiempo apareció una epidemia de sarampión que tuvo como consecuencia el contagio de 50 niños no vacunados. Ninguno de los 111 niños vacunados adquirió la enfermedad, pese al contacto íntimo de todos los niños del Asilo.