The reproductive cycle of Squamata reptiles is often associated with environmental conditions, such as rainfall. In this respect, seasonal variations may affect the morphology of the ovarian follicles, which are associated with vitellogenesis. The present study describes histological alterations in the ovarian cycle of two lizard species, Tropidurus hispidus (Spix, 1825) and Tropidurus semitaeniatus (Spix, 1825), which inhabit a caatinga region in the state of Rio Grande do Norte. Our goal was to identify morphological differences in the ovarian follicles at each phase of vitelloge nesis and to ascertain if they are associated with rainfall. Three follicular phases were identified in both species: pre-vitellogenesis, vitellogenesis and follicular atresia. An additional phase, the luteal, was found only in T. hispidus. During the development of these phases, vitellus was deposited inside the oocyte and there were identifiable alterations in the granulosa and thecal layers. Rainfall was found to influence the gonadal cycle.

This study assessed the reproductive and fat body cycles of Tropidurus hispidus (Spix, 1825) and T. semitaeniatus (Spix, 1825) in an area of caatinga in the Serido of Rio Grande do Norte, Brazil, from October 2006 to May 2008. In both species, the females were reproductively active from the middle of the dry season to the beginning of the rainy season. Female reproductive activity was influenced by precipitation, whereas males exhibited spermatozoa in their testes throughout the year, and their reproductive activity was not related to any of the climatic variables analyzed. Mean clutch size (± SD) was 8.1 ± 2.0 and 2.1 ± 0.6 eggs in T. hispidus and T. semitaeniatus, respectively, and was significantly related to female body size only in T. hispidus. The fat stock varied inversely with reproductive activity in the two species, and there was no difference in fat body mass between females and males. The effects of precipitation on the length of the breeding season of these two Tropidurus species suggest that their reproductive cycles are related to the microclimatic conditions suitable for embryo development, as well as for the neonates' emergence and survival especially during the rainy season, which may offer greater food availability to the hatchlings.

Este estudio evaluó los ciclos reproductivos y de grasa corporal de Tropidurus hispidus (Spix, 1825) y T. semitaeniatus (Spix, 1825) en una área de caatinga en el Seridó de Rio Grande do Norte, Brasil, de octubre de 2006 a mayo de 2008. En ambas especies, las hembras se encontraron reproductivamente activas a partir de mediados de la estación seca para el inicio de la temporada de lluvias. La actividad reproductiva de las hembras fue influenciada por las precipitaciones, mientras que los machos presentaron espermatozoides en los testículos durante todo el año, y su actividad reproductiva no fue relacionada con ninguna de las variables climáticas analizadas. El tamaño medio (± DE) de la nidada fue de 8.1 ± 2.0 y 2.1 ± 0.6 huevos en T. hispidus y T. semitaeniatus, respectivamente, y se relacionó significativamente con el tamaño corporal de la hembra solo en T. hispidus. La reserva de grasa varió inversamente con la actividad reproductiva en las dos especies, y no hubo diferencia en la cantidad de grasa corporal entre hembras y machos. Los efectos de la precipitación sobre la duración de la temporada reproductiva de estas dos especies de Tropidurus sugieren que sus ciclos reproductivos están relacionados con las condiciones microclimáticas adecuadas para el desarrollo del embrión, así como para la emergencia de los recién nacidos y su supervivencia, especialmente durante la temporada de lluvias, que es la que puede ofrecer una mayor disponibilidad de alimentos para las crías.

A sulfated polysaccharide (SPSG) was successfully isolated from seagrass Halodule wrightii Asch., Cymodoceaceae, and its antioxidant and anticoagulant activities were investigated. The data presented here showed that the SPSG is a 11 kDa sulfated heterogalactan with a sulfatation degree of 20.63% and it also contains glucose and xylose. SPSG antioxidant activities were evaluated using several in vitro assays and the anticoagulant activity was evaluated by aPTT and PT tests. These assays suggested that the SPSG possessed remarkable antioxidant properties in different in vitro assays and an outstanding anticoagulant activity 2.5-fold higher than that of heparin Clexane® in the aPTT test. This data represents the first reported on the sulfated polysaccharide biological activities from seagrass. These results indicate that SPSG can be considered in the future as a drug utilized in treating diseases from these systems.

This study characterized the morphology of the digestive tube of five species of sea turtles. We used specimens found dead along the coast of the state Rio Grande do Norte, as well as specimens accidentally killed as a result of pelagic longline fishing. Nineteen animals of the following species were analyzed: Chelonia mydas (Linnaeus, 1758) (n = 9), Lepidochelys olivacea (Eschscholtz, 1829) (n = 6), Caretta caretta (Linnaeus, 1758) (n = 2), Eretmochelys imbricata (Linnaeus, 1766) (n = 1) and Dermochelys coriacea (Vandelli, 1761) (n = 1). After opening the plastron, we removed the digestive organs and described the external and internal morphology of each organ. The esophagus of all species had pointed papillae on the mucosa. The stomach varied in shape among species. Differences were found in the mucosa of the small intestine. It was reticular in the duodenum, and longitudinal rectilinear in the jejunum/ileum. In all species an alternation of saccular and narrow regions was observed in the large intestine. The exception was D. coriacea, in which the mucosa of the entire large intestine had irregularly distributed folds. The pattern of the esophagus was the same in all species. The morphology of the stomach differed among species, and these differences reflect their diets. In addition, the distribution pattern of the folds on the mucosa of the small intestine varied between regions of the intestine and among species.

Fucan is a term used to denominate a family of sulfated polysaccharides rich in L-fucose. The brown alga Spatoglossum schröederi, Dictyotaceae, synthesizes three heterofucans named A, B, and C. Fucan A is a non-anticoagulant heterofucan which possesses potent antithrombotic (in vivo) and antiproliferative (in vitro) activities. However, its toxicity in vivo has not been determined. The present study examined the acute and subchronic toxicity of the fucan A in Wistar rats after subcutaneous administration. After that, the animals were killed and examined. The results showed in the acute study that fucan A did not cause general adverse effects and mortality in the concentrations 0, 20, 100, 1000, and 2000 µg/g body weight per rat for seven days. Regarding the subchronic study, the data showed that the fucan A did not cause any change in hematological and biochemistry parameters, as well as in the morphology, and in the size of the rat's organs analyzed at a concentration of 20 µg/g body weight per rat during a 62-day period. In conclusion, this study indicates this heterofucan is a compound with potential pharmacological value that has no toxicity in vivo.

Para avaliar a morfologia do tubo digestório da tartaruga verde (Chelonia mydas) 10 animais, 9 juvenis e 1 adulto, foram analisados. A retirada dos órgãos digestórios procedeu-se após abertura do plastrão. A descrição e a medida do comprimento de cada órgão [esôfago, estômago, intestino delgado (ID) e intestino grosso (IG)] foram realizadas com o tubo digestório aberto. Os resultados mostraram que tanto nos animais juvenis como no adulto, o esôfago foi marcado pela presença de papilas pontiagudas em sua mucosa interna. O estômago apresentou aspecto saculiforme com fundo cego. No ID foi observado pregas reticulares na mucosa duodenal, enquanto o jejuno e do íleo mostrou pregas retilíneas longitudinais. O IG foi marcado pela alternância de regiões abauladas (haustros ou saculações) e estreitamentos. A microscopia do tudo digestório em C. mydas revelou esôfago com mucosa pregueada revestida por epitélio estratificado pavimentoso queratinizado. O estômago mostrou-se dividido em regiões: cárdica, fúndica, pilórica, as quais diferiam quanto ao número de glândulas e disposição da camada muscular. O ID apresentou-se marcado por vilosidades, e o IG por mucosa pregueada contendo glândulas na lâmina própria. A morfologia do tubo digestório da tartaruga verde mostrou-se adaptada ao seu hábito alimentar, possuindo especializações e um longo trato digestório que promove o aumento da superfície de absorção, já que seu alimento é de difícil digestão.

The morphology of the digestive tube of the green turtle (Chelonia mydas) was evaluated. Nine young e 1 adult turtles were analyzed. The digestive organs withdrew occurred after plastron opening. The length's description and measurement from each organ [esophagus, stomach, small intestine (SI) and large intestine (LI)] were made with digestive tube opened. The results showed that in both the adult and young animals, the esophagus from all species were marked by the presence of pointed papillae on internal mucous. The stomach presented saclike shape with blind fund. In the SI, reticular pleats in the duodenal mucous membrane have been observed, while the jejune and the ileum showed rectilinear longitudinal pleats. The LI was marked by the alternation of arched areas (haustra or sacculations) and narrowings. The microscopy of digestive tube from C. mydas revealed esophagus with folded mucous covered by keratinized and stratified squamous epitheliums. The stomach was divided in regions: cardiac, fundic e pyloric which differed as to the number of glands and the muscle layer's arrangement. The SI presented marked by microvillus, and LI by folded mucous with glands the lamina propria. The morphology of the tube digestive of the green turtle showed to be adapted to your eating habits. A long the digestive tract and specializations provide greater area of absorption and more efficiency in digestion in this species.