Hsp70 gene polymorphisms in farmed marine shrimp Litopenaeus vannamei populations exposed to white spot disease and infectious myonecrosis.

Single nucleotide polymorphisms (SNPs) are the best genetic markers for associative studies of the immune system in invertebrates. In the marine shrimp Litopenaeus vannamei, SNPs linked to disease resistance have been reported for some genes, such as hemocyanin, anti-lipopolysaccharide factor, and heat-shock protein 70 (Hsp70). In the present study, polymorphisms in the Hsp70 gene were investigated among three commercial L. vannamei populations bred in Northeast and South Brazil. The first population withstood a strong white spot disease outbreak; the second population suffered extended exposure to infectious myonecrosis; the third population was a high health population, which was experimentally infected with white spot syndrome virus (WSSV) in the present study. All five previously known SNPs (C661A, T712C, C782T, C892T, and C1090T) were detected in the coding region of Hsp70, by Sanger sequencing of 119 shrimp. Significant differences in genetic and genotype frequencies among populations were observed for C661A, C892T, and C1090T. In the population submitted to WSSV challenge, no frequency differences were found between dead and surviving shrimp groups. These results indicate that the Hsp70 polymorphisms described here cannot be associated with WSSV tolerance. However, significant frequency differences were observed for the population exposed to infectious myonecrosis virus. This is the first time that L. vannamei Hsp70 gene polymorphisms were studied in correlation with these important shrimp viruses.

Perkinsus sp. infecting the oyster Crassostrea rhizophorae from estuaries of the septentrional Northeast, Brazil.

The mangrove oyster Crassostrea rhizophorae is an estuarine resource exploited by riverside communities in Northeast Brazil. Despite its socioeconomic importance, studies on the health status of this bivalve are scanty in this region. The purpose of the present study was to investigate the presence of the protozoan Perkinsus sp. in C. rhizophorae collected in August and September 2011 in three estuaries of the septentrional Northeast, Brazil: Jaguaribe (Ceará), Camurupim (Piauí) and Carnaubeiras (Maranhão) (n= 150 specimens/site). The samples were submitted to Ray's fluid thioglycollate medium (RFTM), PCR and histology assays. The RFTM assay revealed spherical, blue or bluish-black hypnospores of the genus Perkinsus in 50 specimens (Jaguaribe= 17.3%, Camurupim= 5.3%, Carnaubeiras= 10.6%). The intensity of the infection ranged from very light (1-10 cells per slide) to severe (more than 40 cells in each of 10 fields of the slide) for Jaguaribe; very light for Camurupim and very light to moderate (at least 40 cells observed in each of 10 fields of the slide) for Carnaubeiras. When submitted to confirmatory PCR analysis, 6 cases were confirmed (Jaguaribe=3, Camurupim=1, Carnaubeiras=2). The histology confirmed 21 cases of infection in specimens from the three estuaries. Although local collectors have reported no mortality in oyster populations that might be attributed to infection by Perkinsus, health surveillance of oyster populations in the septentrional region of Northeast Brazil is advisable.

Perkinsus sp. infecting the oyster Crassostrea rhizophorae from estuaries of the septentrional Northeast, Brazil / Perkinsus sp. infectando a ostra Crassostrea rhizophorae de estuários do Nordeste setentrional, Brasil

Abstract The mangrove oyster Crassostrea rhizophorae is an estuarine resource exploited by riverside communities in Northeast Brazil. Despite its socioeconomic importance, studies on the health status of this bivalve are scanty in this region. The purpose of the present study was to investigate the presence of the protozoan Perkinsus sp. in C. rhizophorae collected in August and September 2011 in three estuaries of the septentrional Northeast, Brazil: Jaguaribe (Ceará), Camurupim (Piauí) and Carnaubeiras (Maranhão) (n= 150 specimens/site). The samples were submitted to Ray’s fluid thioglycollate medium (RFTM), PCR and histology assays. The RFTM assay revealed spherical, blue or bluish-black hypnospores of the genus Perkinsus in 50 specimens (Jaguaribe= 17.3%, Camurupim= 5.3%, Carnaubeiras= 10.6%). The intensity of the infection ranged from very light (1-10 cells per slide) to severe (more than 40 cells in each of 10 fields of the slide) for Jaguaribe; very light for Camurupim and very light to moderate (at least 40 cells observed in each of 10 fields of the slide) for Carnaubeiras. When submitted to confirmatory PCR analysis, 6 cases were confirmed (Jaguaribe=3, Camurupim=1, Carnaubeiras=2). The histology confirmed 21 cases of infection in specimens from the three estuaries. Although local collectors have reported no mortality in oyster populations that might be attributed to infection by Perkinsus, health surveillance of oyster populations in the septentrional region of Northeast Brazil is advisable.

Resumo A ostra-do-mangue Crassostrea rhizophorae é um recurso estuarino explorado por comunidades ribeirinhas do Nordeste do Brasil. Apesar de sua importância socioeconômica, estudos sobre o estado de saúde deste bivalve são escassos na região. O objetivo deste estudo foi investigar a presença do protozoário Perkinsus sp. em C. rhizophorae coletada em agosto e setembro de 2011, em três estuários da região setentrional do Nordeste brasileiro: Jaguaribe (Ceará), Camurupim (Piauí) e Carnaubeiras (Maranhão) (n = 150 espécimes/local). As amostras foram submetidas ao meio líquido de tioglicolato de Ray (RFTM), PCR e ensaios histológicos. A análise em RFTM revelou hipnósporos esféricos azuis ou preto-azulados do gênero Perkinsus em 50 espécimes (Jaguaribe= 17,3%, Camurupim= 5,3%, Carnaubeiras= 10,6%). A intensidade de infecção variou de muito leve (1-10 células por lâmina) a severa (mais de 40 células em cada um dos 10 campos da lâmina) para o Rio Jaguaribe; muito leve para o Rio Camurupim e muito leve a moderada (pelo menos 40 células observadas, em cada um dos 10 campos da lâmina) para o Rio Carnaubeiras. Quando submetidos à análise confirmatória por PCR, foram confirmados 6 casos (Jaguaribe= 3, Camurupim= 1, Carnaubeiras= 2). A histologia confirmou 21 casos de infecção em espécimes dos três estuários. Embora os coletores locais não tenham relatado nenhuma mortalidade em populações de ostras que pudesse ser atribuída à infecção por Perkinsus, é aconselhável um monitoramento sobre o estado de saúde de populações de ostras da região.

Prospective molecular markers for the identification of illegally traded angelsharks (Squatina) and dolphin (Sotalia guianensis).

Endangered angelsharks and a protected dolphin species are illegally traded in Brazil. In this study, we determined prospective molecular markers for detecting these species in the trade of angelshark carcasses and 'dolphin' eyeball amulets. We compiled publicly available as well as new and unpublished cytochrome b (cyt b) DNA sequences for species involved in these trades. These sequences were digested in silico using restriction enzymes. We then described prospective polymerase chain reaction (PCR)-restriction fragment length polymorphism markers for distinguishing between protected species and the species whose trade was legally allowed in these two trade groups. The prospective marker for identifying angelshark carcasses consists of cyt b PCR and digestion by BstXI, BsgI, BspMI, BsrDI, and HaeII restriction enzymes. The prospective marker for identifying eyeball amulets consists of cyt b PCR and digestion by ApoI, BtsI, HindII, BsaAI, BplI, and SspI restriction enzymes. This is the first study to deposit in GenBank cyt b sequences for the angelshark species Squatina argentina, Squatina guggenheim, and Squatina occulta. Moreover, the S. argentina haplotype is the first DNA sequence for this species deposited in GenBank.

Chromosomes of Gymnothorax funebris and the karyotypical differentiation within Gymnothorax (Anguilliformes: Muraenidae).

Cytogenetic studies in Gymnothorax funebris revealed a diploid chromosome number 2n = 42 (6 metacentrics, 4 submetacentrics, and 32 acrocentrics, FN = 52). The results obtained are novel and similar to those previously described for species belonging to Muraenidae family. The conventional karyotype is also novel and divergent from other species of the genus Gymnothorax, where a higher proportion of metacentric chromosomes predominate. The data are reported and discussed considering the cytotaxonomy of the genus. These results strongly support the current view that chromosomal alterations such as centric fusion and Robertsonian's translocations have an important role in the evolution of this group.

Intraflagellar transport complex in Leishmania spp. In silico genome-wide screening and annotation of gene function.

Flagella are constructed and maintained through the highly conserved process of intraflagellar transport (IFT), which is a rapid movement of particles along the axonemal microtubules of cilia/flagella. Particles that are transported by IFT are composed of several protein subunits comprising two complexes (A and B), which are conserved among green algae, nematodes, and vertebrates. To determine whether or not homologues to members of the IFT complex proteins are conserved in Leishmania spp, we scanned genomes, transcriptomes and proteomes of Leishmania species in a search for putative IFT factors, which were then identified in silico, compared, cataloged, and characterized. Since a large proportion of newly identified genes in L. major remain unclassified, with many of these being potentially Leishmania- (or kinetoplastid-) specific, there is a need for detailed analyses of homologs/orthologs that could help us understand the functional assignment of these gene products. We used a combination of integrated bioinformatics tools in a pathogenomics approach to contribute to the annotation of Leishmania genomes, particularly regarding flagellar genes and their roles in pathogenesis. This resulted in the formal in silico identification of eight of these homologs in Leishmania (IFT subunits, 20, 27, 46, 52, 57, 88, 140, and 172), along with others (IFTs 71, 74/72, and 81), as well as sequence comparisons and structural predictions. IFT, an important flagellar pathway in Leishmania, begins to be revealed through screening of trypanosomatid genomes; this information could also be used to better understand fundamental processes in Leishmania, such as motility and pathogenesis.

Intraflagellar transport complex in Leishmania spp. In silico genome-wide screening and annotation of gene function

Flagella are constructed and maintained through the highly conserved process of intraflagellar transport (IFT), which is a rapid movement of particles along the axonemal microtubules of cilia/flagella. Particles that are transported by IFT are composed of several protein subunits comprising two complexes (A and B), which are conserved among green algae, nematodes, and vertebrates. To determine whether or not homologues to members of the IFT complex proteins are conserved in Leishmania spp, we scanned genomes, transcriptomes and proteomes of Leishmania species in a search for putative IFT factors, which were then identified in silico, compared, cataloged, and characterized. Since a large proportion of newly identified genes in L. major remain unclassified, with many of these being potentially Leishmania- (or kinetoplastid-) specific, there is a need for detailed analyses of homologs/orthologs that could help us understand the functional assignment of these gene products. We used a combination of integrated bioinformatics tools in a pathogenomics approach to contribute to the annotation of Leishmania genomes, particularly regarding flagellar genes and their roles in pathogenesis. This resulted in the formal in silico identification of eight of these homologs in Leishmania (IFT subunits, 20, 27, 46, 52, 57, 88, 140, and 172), along with others (IFTs 71, 74/72, and 81), as well as sequence comparisons and structural predictions. IFT, an important flagellar pathway in Leishmania, begins to be revealed through screening of trypanosomatid genomes; this information could also be used to better understand fundamental processes in Leishmania, such as motility and pathogenesis.

Population structure of Litopenaeus schmitti (Decapoda: Penaeidae) from the Brazilian coast identified using six polymorphic microsatellite loci.

The population structure of the only Litopenaeus species occurring in Brazilian waters, the white shrimp L. schmitti, was surveyed by screening six microsatellite loci. High diversity (HE = 0.863; average number of alleles per locus = 37.8) was found across eight geographical locations (2 degrees S to 27 degrees S). Estimates of overall FST(0.0060) were low but significantly different from zero (P < 0.05). FST pairwise estimates and amova revealed a significant discontinuity around a major biogeographical boundary, near Cabo Frio, at 23 degrees S. This separation may have been caused either by historical or on-going hydrogeographical and/or selective factors.

Molecular phylogeny of western Atlantic Farfantepenaeus and Litopenaeus shrimp based on mitochondrial 16S partial sequences.

Partial sequences for the 16S rRNA mitochondrial gene were obtained from 10 penaeid shrimp species: Farfantepenaeus paulensis, F. brasiliensis, F. subtilis, F. duorarum, F. aztecus, Litopenaeus schmitti, L. setiferus, and Xiphopenaeus kroyeri from the western Atlantic and L. vannamei and L. stylirostris from the eastern Pacific. Sequences were also obtained from an undescribed morphotype of pink shrimp (morphotype II) usually identified as F. subtilis. The phylogeny resulting from the 16S partial sequences showed that these species form two well-supported monophyletic clades consistent with the two genera proposed in a recent systematic review of the suborder Dendrobranchiata. This contrasted with conclusions drawn from recent molecular phylogenetic work on penaeid shrimps based on partial sequences of the mitochondrial COI region that failed to support recent revisions of the Dendrobranchiata based on morphological analysis. Consistent differences observed in the sequences for morphotype II, coupled with previous allozyme data, support the conclusion that this is a previously undescribed species of Farfantepenaeus.

[Parathyroid hormone levels in the aged]. / Il paratormone nell'anziano.

PTH is tested in 36 normal subjects over 65 years. A radioimmunoassay is used, which needs a bovine antiserum produced against COOH terminal fragments of the hormone. Serum PTH level results normal in the elderly, and it doesn't show modifications also in the sub-groups, under and over 75 years. No modification is noted respect the sex, too.