Spatio-temporal Distribution Pattern of Oyster Larvae in Guaratuba Bay, Paraná State - Brazil

HIGHLIGHTS Crassostrea oysters larvae patterns in estuarine environments. Larvae distribution patterns in Guaratuba Bay (Paraná State - Brazil).

Abstract Crassostrea oysters present planktonic/planktotrophic larval development. Thus, it is essential knowing larvae distribution patterns in estuarine environments presenting oyster farms and spat collection. The aim of the current research is to investigate the spatio-temporal distribution of oyster larvae in Guaratuba Bay (Paraná State - Brazil) based on monthly samplings conducted with a plankton net (50 cm diameter and 225 µm mesh size) from June 2003 to June 2004 in three different points (Point I - bay´s entrance; Point II - cultivation park; Point III - median sector of the bay). Plankton samples were preserved in 4% buffered formaldehyde. They were concentrated and quantified in the laboratory. The total number of larvae in the sample from each net was counted and corrected to a standard larvae/m3 collection tow. Data about sea water temperature, salinity, transparency and pluviosity were also collected. Based on results about the spatial distribution of larvae, mean density was 33.30 ±42.73 larvae/m³ in Point I; 17.84 ±16.88 larvae/m³ in Point II and 55.53 ±78.31 larvae/m³ in Point III, during the studied period. Spring and Summer were the seasons recording the most expressive mean number of larvae; the largest concentration of them was found in Point III, in the middle section of the bay.

Ultrastructure of phagocytes and oocysts of Nematopsis sp. (Apicomplexa, Porosporidae) infecting Crassostrea rhizophorae in Northeastern Brazil / Ultraestrutura de fagócitos e oocistos de Nematopsis sp. (Apicomplexa, Porosporidae) infectando Crassostrea rhizophorae no Nordeste brasileiro

Abstract This work describes the detailed ultrastructural morphology of the phagocyte imprisoning an oyster of Nematopsis (Apicomplexa) found in Crassostrea rhizophorae, in the city of Maceió (AL), Brazil. The highly infected hosts had half-open leaflets with weak, slow retraction of the adductor muscles. Variable number of ellipsoid oocytes, either isolated and or clustered, was found between myofibrils of the adductor muscle. Each oocyst was incarcerated in a parasitophorous vacuole of host uninucleated phagocyte. The oocysts were composed of a dense wall containing a uninucleate vermiform sporozoite. The wall of the fine oocysts was composed of homogeneous electron-lucent material formed by three layers of equal thickness, having a circular orifice-micropyle obstructed by the operculum. The oocysts presented ellipsoid morphology with their wall was surrounded by a complex network of numerous microfibrils. Important details of the taxonomic value were visualized such as the ultrastructural organization of the oocyst wall and the organization of the micropyle and operculum, beyond the microfibrils that protrude from the oocyst wall only observed by transmission electron microscopy (TEM) and that may aid in the identification of the species. However, in order to clarify the systematic position of the species reported of the genus Nematopsis, it is important to proceed with genetic analyses.

Resumo Este trabalho descreve a morfologia ultraestrutural detalhada do fagócito encarcerando um oocisto de Nematopsis (Apicomplexa) encontrado em Crassostrea rhizophorae, na cidade de Maceió (AL), Brasil. Os hospedeiros muito infectados apresentavam valvas entreabertas com retração fraca e lenta dos músculos abdutores. Número variável de oócitos de forma elipsoide, isolados e ou agrupados foi encontrado entre as miofibrilas do músculo abdutor. Cada oocisto estava encarcerado num vacúolo parasitóforo do fagócito uninucleado do hospedeiro. Os oocistos eram compostos por uma parede densa contendo um esporozoíto vermiforme uninucleado. A parede dos oocistos finos era composta de material electron-lucente homogêneo formado por três camadas de espessura igual, possuindo um orifício circular - micrópila, obstruída pelo opérculo. Os oocistos apresentavam morfologia elipsoide, sua parede era circundada por uma complexa rede de numerosas microfibrilas. Detalhes de valor taxonômico importantes foram visualizados tais como: a organização ultraestrutural da parede do oocisto e a organização da micrópila e do opérculo, além das microfibrilas que se projetam da parede do oocisto, estrutura apenas observada em microscopia eletrônica de transmissão (MET) e que pode auxiliar na identificação da espécie. Contudo, para esclarecer a posição sistemática da maioria das espécies relatadas do gênero Nematopsis é importante prosseguir com as análises genéticas.

Effects of Chaihu-Longgu-Muli Decoction on the levels of blood superoxide dismutase and maiondiaidehyde in Temporal Lobe Epilepsy patients / 中国医师杂志

Objective To investigate the effects of Chaihu-Longgu-Muli Decoction (CLMD) on superoxide dismutase (SOD) and maiondiaidehyde (MDA) in patients with temporal lobe epilepsy (TLE).Methods 65 patients with TLE were randomly divided into Oxcarbazepine group (n =32) and Oxcarbazepine + CLMD group (n =33).After 28 d,the curative effect,SOD,MDA changes in serum and side effect were observed between two groups.Results The clinical effective rate in Oxcarbazepine + CLMD group was 87.8％,slightly higher than that of the Oxcarbazepine group(53.1％) (P ＜0.05).After treatment,serum SOD was significantly higher in the patients than before treatment in two groups,but serum MDA was significantly lower(P ＜ 0.05 or P ＜ 0.01),while the above changes were more obvious in the Oxcarbazepine + CLMD group (P ＜ 0.05).No statistically significant differences of side effect (P ＞ 0.05).Conclusions CLMD has higher curative effect with less side effect,which can lead to increase of the level of SOD and decrease of the level of MDA,and the mechanism is related to oxidative stress.

Immunomodulatory effect of oyster peptide on immunosuppressed mice / 北京大学学报(医学版)

Objective:To evaluate the immunomodulating effect of oyster peptide on immunosup-pressed mice.Methods:ICR mice injected with cyclophosphamide (CTX)were adopted as the module group,with mice without treatment as the control group,and different dosages of oyster peptide (0.5 g/kg,1 .0 g/kg,and 2.0 g/kg)were given to the low,middle,and high groups for 1 5 days.The body weight,spleen,and thymus weight of the mice,structures under the microscope of the immune organs, numbers of white blood cells,ratios of T lymphocyte subsets,immune cytokines and numbers of nuclear cells,and DNA content in bone marrow were all assessed.Results:Compared with the control group, the structures of thymus and spleen of the mice in the CTX group appeared obscure and shrunk when ob-served under microscope,the number of their white blood cells declined (P =0.04),the proportion of their CD3 +T cells in peripheral blood declined (P =0.003),the proportion of their CD8 +T cells in pe-ripheral blood declined (P =0.002),the concentration of their IL-5 in peripheral blood significantly in-creased (P <0.01 ),the concentration of their nucleated cells and DNA density in bone marrow de-creased (P =0.04,P <0.01 ).Oyster could improve the structures of thymus and spleen of the immuno-suppressed mice.Compared with the CTX group,the number of white blood cells in 2.0 g/kg group in-creased (P =0.003),the proportion of CD3 +T cells in peripheral blood in 1 .0 g/kg group (P =0.04) and 2.0 g/kg group (P =0.02)increased,the proportion of CD8 +T cells in peripheral blood in 2.0 g/kg group increased (P =0.002),the concentration of IL-5 in peripheral blood in all the oyster treated groups increased (P <0.01 in 0.5 g/kg,1 .0 g/kg,and 2.0 g/kg groups),the concentration of IL-1 7 in peripheral blood in 2.0 g/kg group decreased (P =0.03),the concentration of nucleated cells in bone marrow of all the oyster treated groups increased (0.5 g/kg vs.CTX,P =0.04;1 .0 g/kg vs. CTX,P =0.02;2.0 g/kg vs.CTX P =0.01 ),the DNA content in bone marrow of all the oyster treated groups increased (P <0.01 in the 0.5 g/kg,1 .0 g/kg,and 2.0 g/kg groups).Conclusion:Oyster peptide could improve the structures of immune organs of the CTX-induced immunosuppressed mice,re-cover the imbalances of T lymphocyte subsets,improve the immune cytokines and increase numbers of nucleated cells and DNA content in bone marrow,thus improving the immunologic function.

Qualidade microbiológica da água da cultura de ostras comercializadas em Cananeia-SP, Brasil / Microbiological quality of cultivation water used for oysters marketed in Cananeia-SP, Brazil

Bivalves representam as condições do ambiente em que são cultivadas ostras, sendo portanto vital que esses organismos não estejam contaminados, pois podem representar um risco grave para a saúde pública. Este estudo teve como objetivo avaliar a qualidade microbiológica da água para o cultivo de ostras da Cooperostra (cooperativa de produtor), em Cananeia-SP, Brasil. Os coliformes totais e fecais foram analisados . Os resultados mostraram que a qualidade da água não foi satisfatória, de acordo com a legislação brasileira, exceto por alguns meses. A interferência sazonal foi analisada e uma alta correlação positiva foi verificada, estando a concentração de coliformes baixa no inverno. O índice pluviométrico apresentou correlação alta e positiva para os microrganismos analisados.

Bivalves represent the environment conditions where oysters are farmed, thus is vital that these organisms are not contaminated because they can represent a serious risk to the public health. This study aimed to assess the microbiological quality of water for the cultivation of oysters of Cooperostra (cooperative of producer) in Cananeia-SP, Brazil. The total and fecal coliforms were analyzed. The results showed that water quality were not satisfactory, according to Brazilian legislation, except for some months. The seasonal interference was analysed and a high positive correlation was verified, with low coliforms concentration in winter. The pluviometric index showed a high positive correlation to the microorganisms analysed.

Molecular identification, phylogeny and geographic distribution of Brazilian mangrove oysters (Crassostrea)

Oysters (Ostreidae) manifest a high degree of phenotypic plasticity, whereby morphology is of limited value for species identification and taxonomy. By using molecular data, the aim was to genetically characterize the species of Crassostrea occurring along the Brazilian coast, and phylogenetically relate these to other Crassostrea from different parts of the world. Sequencing of the partial cytochrome oxidase c subunit I gene (COI), revealed a total of three species of Crassostrea at 16 locations along the Brazilian coast. C. gasar was found from Curuçá (Pará state) to Santos (São Paulo state), and C. rhizophorae from Fortim (Ceará state) to Florianópolis (Santa Catarina state), although small individuals of the latter species were also found at Ajuruteua beach (municipality of Bragança, Pará state). An unidentified Crassostrea species was found only on Canela Island, Bragança. Crassostrea gasar and C. rhizophorae grouped with C. virginica, thereby forming a monophyletic Atlantic group, whereas Crassostrea sp. from Canela Island was shown to be more similar to Indo-Pacific oysters, and either arrived in the Atlantic Ocean before the convergence of the Isthmus of Panama or was accidentally brought to Brazil by ship.