CARACTERISTCS AND IMPORTANCE OF PLANKTONIC FLAGELLATES IN MARINE COASTAL AND OCEANIC ECOSYSTEMS

Flagelados constituem um grupo morfologicamente e fisiologicamente diversificado do plâncton, com representantes de todas as divisões do Reino Protoctista. A grande importância destes organismos reside em sua diversidade metabólica, no pequeno tamanho e na capacidade de movimento, tornando-os mais competitivos em ambientes oligotróficos com baixa e continua entrada de nutrientes. Nos últimos 25 anos, houve um significativo aumento no conhecimento sobre esses organismos, em conseqüência do avanço tecnológico e do interesse crescente: entretanto é consenso, que o número de espécies ainda não descritas excede o número daquelas já conhecidas. As dificuldades no estudo de flagelados devem-se ao seu pequeno tamanho, à natureza delicada de seu revestimento, a deformação e/ou contração das células preservadas e a dificuldade em trabalhar com células vivas, essencial para observação da forma, tamanho e do seu movimento. A freqüente necessidade de microscópio eletrônico para a identificação de espécies, que depende de detalhes submicroscópicos, c a complexidade e desco­nhecimento dos ciclos de vida de muitas espécies também representam um obstáculo. Em águas costei­ras e oceânicas brasileiras foram realizados poucos estudos sobre flagelados planctônicos até a presente data. A revisão dos dados existentes revela que a maioria das espécies registradas pertence ao grupo dos cocolitoforídeos (> 60%); os outros grupos são Chlorophyceae, Prasinophyceae, Chrysophyceae, Raphidophyceae, Cryptophyta, Euglenophyta e Haptophyta. Os flagelados (l05- 106 células l-1) são orga­nismos predominantes em águas oceânicas, mas também em áreas costeiras como no estuário da Lagoa dos Patos, eles são proporcionalmente mais importantes do que o microplâncton na maior parte do ano, contribuindo com 70% da clorofila a e da produção primária particulada total. A presença de flagelados potencialmente nocivos tem sido registrada em vários pontos da costa brasileira, sugerindo urna ampla ocorrência c um risco potencial para o ambiente marinho.Marine flagellates are morphologically and physiologically diverse planktonic organisms including several taxonomic Divisions of the Kingdom Protoctista. The ecological importance of flagellates comes from their diverse metabolic capacity, smal1 size and motility, thus having great competitive advantage in environments with low but continued nutrient inputs. The knowledge of this group has improved over the last 25 years due te development of new techniques and increasing interest; however there is a consensus that the number of undescribed species stil1 exceeds the number of known ones. Difficulties in flagellate studies concerned with their small size, delicate nature of cell covering, shrinking or deformation of preserved cells thus requiring examination of alive cells for cell size, shape, and motility observation. The reliable identification of many species depends on submicroscopic details, requiring electronic microscope thecniques; the complexity of their life cycles also impose difficulties.  Marine flagellates in Brazilian coastal and oceanic waters are poorly known, with few studies conducted up to the present, there we present a review of existing data on the occurrence of flagel1ates over the Brazilian coast. Most reported flagel1ate species are calcified coccolithoforids (>60%) and the remaining groups are Chlorophyceae, Prasinophyccac, Chrysophyccae, Raphidophyceae, Cryptophyta, Euglenophyta and Haptophyta, Flagellatcs (105 and 106cells l-1) are the predominant organisms in oceanic waters, but also in inshore areas like Lagoa dos Patos estuary, they are relatively more important than microplankton during the year, contributing with 70% of chlorophyll a and particulate primary production. Potentially harmful flagel1ates have been recorded in different sites on the Brazilian coast suggesting that they are widely spread and represent a potential risk to the coastal environment

Nanoflagellates from coastal waters of southern Brazil (32 ° S)

A taxonomic survey of nanoflagellates in the extreme southern Brazilian coastal waters of the Patos Lagoon estuary and adjacent coastal shelf was undertaken using transmission electron microscopy. A total of 44 species was recorded including 42 nanoflagellates, one scale-bearing amoeba and two species incertae sedis. Scale-bearing haptophytes predominated (27 species), followed by prasinophytes (7), chrysophytes (6), pedinellids (2), incertae sedis (2) and one scale-bearing amoeba. Most of the species (42) are new records for Brazilian marine waters. Among the haptophytes, Chrysochromulina was the most species-rich genus, occurring mainly in high salinity waters, and C. simplex was the most frequent species. Scales of undescribed Chrysochromulina species were observed and documented. Other haptophytes present were Prymnesium parvum and Phaeocystis scrobiculata. Five scale-bearing prasinophytes of the genus Pyramimonas were observed including the uncommon species P. longicauda, in addition to Micromonas pusilla and Nephroselmis pyriformis. Among the chrysophytes, the scale-bearing Paraphysomonas species (4) and the loricate Dinobryon belgica were recorded. The pedinellids (Apedinella radians and Para-pedinella reticulata), the amoeba Rabdiophrys sp. and the incertae sedis (Meringosphaera mediterranea, Thau-matomastix sp.) are all scale-bearing protists. The 44 taxa (mostly scale-bearing flagellate species) identified and the finding of further undescribed Chrysochromulina species indicate that only a fraction of the species present in the region are known, and that an effort must be made to increase general knowledge of biodiversity in these southern waters

Loricate Choanoflagellates from the South Atlantic coastal zone (~32 S) including the description of diplotheca tricyclica sp. nov.

The biodiversity of marine heterotrophic protists is poorly known in the South Atlantic coastal zone (~32 °S) especially regarding the nanoflagellates. The presence of loricate choanoflagellates was reported for the first time in the Patos Lagoon estuary and the adjacent coastal zone. Seventeen species of eleven genera of loricate choanoflagellates were observed between October 1998 and May 2000 in fixed water samples (lugol's solution + glutaraldehyde) in a JEM 100-SX transmission electron microscope. Most species were recorded in euhaline and mixopolyhaline waters during the spring and summer, none in autumn and a few (four) in winter. The absence of choanoflagellates at the more sheltered inshore stations is due freshwater influence, and at the beach station,probably due the strong wave action. The probably cosmopolitan species Pleurasiga minima, Cosmoeca norvegica, C. ventricosa and Parvicorbicula circularis were present in spring or summer in the estuary channel and coastal area while Stephanoeca diplocostata which apparently prefers lower temperature, was recorded in winter. Calotheca alata and Campyloacantha spinifera are mainly temperate species and were present in spring. The new species Diplotheca tricyclica was recorded at the estuary channel in the summer 1999, in high salinity water.A biodiversidade de protistas heterotróficos é pouco conhecida na zona costeira do Atlântico Sul (~32 °S), especialmente dos nanoflagelados. No presente estudo, foi registrada pela primeira vez a presença de coanoflagelados loricados no estuário da Lagoa dos Patos e na zona costeira adjacente. Dezessete espécies de onze gêneros de coanoflagelados loricados foram observadas em amostras de água fixadas (solução de lugol + glutaraldeido) coletadas entre outubro de 1998 e maio de 2000, e analisadas em microscópio de transmissão JEM 100-SX. A maior parte das espécies foi registrada em águas euhalinas e mixopolihalinas durante a primavera e o verão, nenhuma no outono e poucas (quatro) no inverno. A ausência de coanoflagelados nas estações mais protegidas deve-se a influência da água doce, e na estação da praia deve-se, provavelmente, a forte ação das ondas. As espécies, provavelmente cosmopolitas, Pleurasiga minima, Cosmoeca norvegica, C. ventricosa and Parvicorbicula circularis ocorreram na primavera ou no verão no canal principal do estuário e na área costeira, enquanto Stephanoeca diplocostata, que aparentemente prefere baixas temperaturas, foi registrada no inverno. Calotheca alata e Campyloacantha spinifera são principalmente de ambientes temperados e estiveram presentes na primavera. Uma espécie nova, Diplotheca tricyclica, foi registrada na área do canal principal do estuário, no verão de 1999, em águas de alta salinidade

Yurek Shabelevsky as the Vagabond, in La concurrence, Covent Garden Russian Ballet, Australian tour, His Majesty's Theatre, Melbourne, October 1938 [picture] /

From: La concurrence (Competition) / ballet by André Derain ; music by Georges Auric.; Inscription: "P20".; Part of the collection: Hugh P. Hall collection of photographs, 1938-1940.; Choreography by Georges Balanchine ; curtain, scenery and costumes by André Derain ; costumes executed by B. Karinska ; scenery executed by Prince A. Schervachidze.; Also available in an electronic version via the internet at: http://nla.gov.au/nla.pic-vn4174106. One of a collection of photographs taken by Hugh P. Hall of 28 ballet productions performed by the Covent Garden Russian Ballet (toured Australia 1938-1939) and the Original Ballet Russe (toured Australia 1939-1940). These are the second and third of the three Ballets Russes companies which toured Australasia between 1936 and 1940. The photographs were taken from the auditorium during a live performance in His Majesty's Theatre, Melbourne and mounted on cardboard for display purposes. For conservation and storage, the photographs have been demounted. The original arrangement of the photographs has been recorded, and details are available from the Pictures Branch of the National Library

Irish study on high-density schizophrenia families:field methods and power to detect linkage

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe serotonin transporter (HTT) is an important candidate gene for the genetic transmission of bipolar disorder. It is the site of action of many antidepressants, and plays a key role in the regulation of serotonin neurotransmission. Many studies of affectively ill patients have found abnormalities in serotonin metabolism, and dysregulation of the transporter itself. The human serotonin transporter has been recently cloned and mapped to chromosome 17. We have identified a PstI RFLP at the HTT locus, and here report our examination of this polymorphism for possible linkage to bipolar disorder. Eighteen families were examined from three populations: the Old Order Amish, Iceland, and the general North American population. In addition to HTT, three other microsatellite markers were examined, which span an interval known to contain HTT. Linkage analyses were conducted under both dominant and recessive models, as well as both narrow (bipolar only) and broad (bipolar + recurrent unipolar) diagnostic models. Linkage could be excluded to HTT under all models examined. Linkage to the interval spanned by the microsatellites was similarly excluded under the dominant models. In two individual families, maximum lod scores of 1.02 and 0.84 were obtained at D17S798 and HTT, respectively. However, these data overall do not support the presence of a susceptibility locus for bipolar disorder near the serotonin transporter