The essential oil of the leaves of Eugenia sulcata, in the Myrtaceae family, has a demonstrated antihypertensive effect, but its effects on heart muscle and its toxicity have not yet been elucidated. Little chemical or biological data are available for E. sulcata, whether emphasizing the beneficial effects or the pharmacological security of this species. This study aims to evaluate myocardial contractility and to analyze angiotensin converting enzyme (ACE) and myosin ATPase activities associated with use of this essential oil. In addition, we evaluated the immunotoxicity of E. sulcata essential oil. Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR) were treated daily for 30 days (10 mg/kg of oil) to evaluate the isometric force of the papillary muscle, ACE measured by fluorimetry, and myosin ATPase activities by inorganic phosphate. Lymphocyte cultures were used to evaluate cytotoxicity, DNA damage, and mutagenicity of the essential oil. The results demonstrate that the treatment did not change the cardiac contraction force and did not alter the functioning of the sarcoplasmic reticulum, extrusion of the membrane calcium, or modify the membrane calcium channels or β-adrenergic receptor activity. Tetanic contractions were potentiated in the SHR animals. Myosin ATPase activity was also increased in the SHR animals. Cardiac ACE activity was reduced in both animal strains, and the serum ACE was reduced only in the SHR animals. The essential oil did not cause cytotoxicity or mutagenicity and presented low DNA damage. Our results demonstrated that the essential oil does not change myocardial contractility and does not present relevant immunotoxicity.

Resumen Esta investigación se llevó a cabo para evaluar los efectos de los extractos de Rheedia longifolia (Clusiaceae), Garcinia xanthochymus (Clusiaceae), Plumbago scandens (Plumbaginaceae) Hovenia dulcis (Rhamnaceae), Malpighia glabra (Malpighiaceae), Euphorbia tirucalli (Euphorbiaceae) y Nerium adelfa (Apocynaceae) sobre la tasa incubación de los huevos de Dermacentor (Anocentor) nitens y Ripicephalus sanguineus (Acari: Ixodidae) en concentraciones de 1.000 ppm. Los extractos de R. longifolia, H. dulcis, M. glabra y E. tirucalli retrasaron significativamente la incubación de los huevos de R. sanguineus en tres días, pero los grupos tratados con los extractos de G. xanthochymus y P. scandens eclosionaron después de 14 días. Para las garrapatas D. (A.) nitens, los extractos de H. dulcis y N. adelfa retrasaron la eclosión de los huevos durante tres días, sin embargo, la acción de los extractos de R. longifolia, G. xanthochymus, P. scandens y E. tirucalli causó un retraso mayor de siete días. Para los dos tipos de garrapatas, los huevos del grupo control tardaron un día para eclosionar. Los extractos H. dulcis y M. glabra fueron eficaces in vitro en huevos de R. sanguineus (89 %) y D. (A.) nitens (100 %) y se pueden considerar como candidatos potenciales para el control biológico de estas garrapatas.

Abstract This investigation was carried out to evaluate the effects of the plant extracts of Rheedia longifolia (Clusiaceae), Garcinia xanthochymus (Clusiaceae), Plumbago scandens (Plumbaginaceae), Hovenia dulcis (Rhamnaceae), Malpighia glabra (Malpighiaceae), Euphorbia tirucalli (Euphorbiaceae) and Nerium adelfa (Apocynaceae) on eggs of Dermacentor (Anocentor) nitens and Ripicephalus sanguineus (Acari: Ixodidae) at concentrations of 1,000 ppm. The extracts had a significant effect on the hatching rate of eggs. The extracts of R. longifolia, H. dulcis, M. glabra and E. tirucalli delayed the hatching of R. sanguineus eggs by three days; however, the group treated with the extracts of G. xanthochymus and P. scandens did not hatch until day fourteen. For the tick D. (A.) nitens, extracts of H. dulcis and N. oleander delayed egg hatching by three days; however, the action of extracts from R. longifolia, G. xanthochymus, P. scandens and E. tirucalli caused a delay of seven days. For the control groups of both species, eggs hatched in one day. H. dulcis and M. glabra were effective in vitro on eggs of R. sanguineus and D. (A.) nitens (89 and 100 %, respectively), and can be considered to be potential candidates for the biocontrol of those ticks.

Se analiza el establecimiento del pez introducido Lepomis gibbosus en una laguna natural de la ciudad de Ouro Preto, Cuenca del Rio Doce, provincia de Minas Gerais, región sureste de Brasil. Cada dos meses se realizaron muestreos con anzuelo y línea, entre marzo 2002-febrero 2003 y se capturaron 226 hembras y 226 machos. Se encontraron hembras y machos en actividad reproductiva durante todo el muestreo. Ovarios con signos de desove con oocitos de diferentes tallas y folículos post-ovulatorios indicaron la puesta parcial para L. gibbosus. La hembra y macho en reproducción más pequeños tenían entre 4.6cm y 4.9cm de longitud, que caracteriza el enanismo. La proporción sexual fue 1:1 y no presentó diferencias bimensuales ni anuales. De las cinco fases del proceso de bioinvasión, se confirmó que L. gibbosus se encuentra en la fase tres, llamada establecimiento a través de la reproducción. Se sugiere aclaración sobre la temática “especie foránea” para evitar la degradación del ambiente con la introducción de peces foráneos en la región.

Minas Gerais is the fourth largest Brazilian state, and has an estimate of 354 native fish species. However, these fish species may be threatened, as this state has the highest rank of fish introductions reported for Brazil and South America. As one from the total of 85 non-native species detected, Lepomis gibbosus was introduced in the 60s to serve both as foragefish and to improve sport fishing. In this study, we evaluated the establishment of L. gibbosus in a shallow lake in the city of Ouro Preto, Doce River basin, state of Minas Gerais, Southeastern Brazil. We collected fish with fishing rods every two months from March 2002-February 2003. Fragments of gonads from a total of 226 females and 226 males were obtained and processed following standard histological techniques; then 5-7μm thickness sections were taken and stained in hematoxylin-eosin. Besides, for each specimen, the biometric measurements included the standard length (SL) and body weight (BW); and the sex ratio was obtained. The reproductive cycle stages were confirmed by the distribution of oocytes and spermatogenic cells. The type of spawning was determined by the frequency distribution of the reproductive cycle stages and ovarian histology. Based on the microscopic characteristics of the gonads, the following stages of the reproductive cycle were determined: one=Rest, two=Mature, three=Spawned for females or Spent for males; males and females in reproduction were found throughout the study period. Post-spawned ovaries containing oocytes in stages one (initial perinucleolar), two (advanced perinucleolar), three (pre-vitellogenic), four (vitellogenic) and post-ovulatory follicles indicated fractionated-type spawning in this species. The smallest breeding male and female measured were 4.6 and 4.9cm standard length, respectively, suggesting stunting. The sex ratio did not vary between males and females along the year and bimonthly, being 1:1. Moreover, L. gibbosus appears to be at stage three of biological invasion: establishment through reproduction. We suggest to deliver information about “non-native species” through lectures in schools, colleges/ universities, NGOs, government and environmental agencies in the cities and villages, in order to try to prevent environmental degradation by the introduction of non-native fish such as L. gibbosus in the region. We also recommend high fines for redhanded, and the import ban of non-native fish species to the region.

Neste trabalho apresentamos os resultados dos estudos sobre as variações das dimensões (comprimento e largura) dos elementos dos vasos através das mensurações microscópicas desses elementos nos diversos anéis de crescimento de dois discos tomados ao nível de D.A.P. de duas plantas adultas do Eucalyptus Saligna Smith. Pudemos também avaliar o aumento do comprimento das fibras em relação aos elementos dos vasos, tomado em substituição às células cambiais que deram origem as fibras e vasos. Os resultados apresentados neste trabalho nos mostram que as variações nas dimensões dos elementos do vaso nos anéis de crescimento, segue o mesmo modelo das variações das fibras, as quais se enquadram dentro das "Leis de SANIO- 1872". Mostra também que o aumento no ritmo de crescimento intrusivo das fibras depois de produzidas é muito maior durante o lenho adulto. Disso se conclui da importância do aproveitamento qualitativo dos Eucalyptus adultos, isto após 10 a 11 anos de idade.

This paper deals with the variation of vessel member dimentions in growth rings taken at the breast height (B.H.) of the trunk o two plants of Eucalyptus Saligna Smith, and the increase of intrusive growth rate of the fiber length as comparing with cambial initial.

O presente trabalho, faz parte de um plano de estudo em desenvolvimento, sôbre fibras lenhosas de Eucalyptus saligna, Smith no Departamento de Botânica (Disciplina Anatomia de Madeira) desde 1966. Nêle apresentamos os resultados da determinação da idade adulta do E. saligna em função da variação do comprimento e da espessura da parede das fibras nos diferentes anéis de crescimento do lenho, de duas árvores com mais de 20 anos de idade. Os resultados das mensurações microscópicas das fibras analisadas num setor apenas e em dois discos tomados ao nível do D.A.P., nos permite afirmar que nas condições do Hôrto de Rio Claro, as duas árvores atingiram a idade adulta entre o 9.º e 10.º anel de crescimento os quais corresponde respectivamente a idade de 9 e 10 anos. Os resultados apresentados nêste trabalho nos forneceu informações importantes para a continuação do plano em desenvolvimento, qual seja o estudo de outros fatôres (longa e curta duração) que afetam a estrutura e as características dos elementos constituintes do lenho que apresentam valor industrial.

The objetive of this study was to get some information about fiber length variation in the growth rings of Eucalyptus saligna, with 21 year old, which data could give the mature age of this plant at São Paulo States. Two disc from two plants were colected at the level of D. B. H. at Forest Experiment Station "Navarro de Andrade" at Rio Claro, in which there were stands of this species, which age was known. From each disc was take one sector of south side of the trunk and the surface was polished with the finality to identify the growth rings by macroscopic and microscopic observation. Since each sector had 21 growth rings and the age of the plants was 21 years old, it was possible to correlated the number of growth rings with the age of the plants. After that, each growth rings from 3 sectors of one plant was macerated in individual vials and 6 or 8 slides was prepared in which 5 fibers and 5 veessels was measured. The statistical analysis showed the following results: 1.º) The analysis of variance of mean fiber length in the 3 sectors point out that the value of residual error was praticaly the same. (See Table I). This make possible to analyse the data of both sectors together, and the analysis of variance for fiber length mean in the growth rings was significant at 1% leve of probability. (See Table II). By using the regression equation it was possible to determine the maximum of the fiber length among the 21 growth rings and also in which the mean value of "Runkel coefficent" reache the assintotic value. The maximum value or fiber length was reached at the 10th growth ring and Runkel coefficent reache between 14th and 15th growth rings in one plant and between 9th and 10th in other. (See Figure 1 and 2). These results led us to conclude that in São Paulo States the mature age in Eucalyptus saligna was reached at the 9th or 10th growth rings, that correspond to 9 or 10 years old.