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Leishmaniasis is an infectious disease caused by Leishmania species. Leishmania amazonensis is a New World Leishmania species belonging to the Mexicana complex, which is able to cause all types of leishmaniasis infections. The L. amazonensis reference strain MHOM/BR/1973/M2269 was sequenced identifying 8,802 codifying sequences (CDS), most of them of hypothetical function. Comparative analysis using six Leishmania species showed a core set of 7,016 orthologs. L. amazonensis and Leishmania mexicana share the largest number of distinct orthologs, while Leishmania braziliensis presented the largest number of inparalogs. Additionally, phylogenomic analysis confirmed the taxonomic position for L. amazonensis within the "Mexicana complex", reinforcing understanding of the split of New and Old World Leishmania. Potential non-homologous isofunctional enzymes (NISE) were identified between L. amazonensis and Homo sapiens that could provide new drug targets for development.

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Endosymbiont-bearing trypanosomatids have been considered excellent models for the study of cell evolution because the host protozoan co-evolves with an intracellular bacterium in a mutualistic relationship. Such protozoa inhabit a single invertebrate host during their entire life cycle and exhibit special characteristics that group them in a particular phylogenetic cluster of the Trypanosomatidae family, thus classified as monoxenics. In an effort to better understand such symbiotic association, we used DNA pyrosequencing and a reference-guided assembly to generate reads that predicted 16,960 and 12,162 open reading frames (ORFs) in two symbiont-bearing trypanosomatids, Angomonas deanei (previously named as Crithidia deanei) and Strigomonas culicis (first known as Blastocrithidia culicis), respectively. Identification of each ORF was based primarily on TriTrypDB using tblastn, and each ORF was confirmed by employing getorf from EMBOSS and Newbler 2.6 when necessary. The monoxenic organisms revealed conserved housekeeping functions when compared to other trypanosomatids, especially compared with Leishmania major. However, major differences were found in ORFs corresponding to the cytoskeleton, the kinetoplast, and the paraflagellar structure. The monoxenic organisms also contain a large number of genes for cytosolic calpain-like and surface gp63 metalloproteases and a reduced number of compartmentalized cysteine proteases in comparison to other TriTryp organisms, reflecting adaptations to the presence of the symbiont. The assembled bacterial endosymbiont sequences exhibit a high A+T content with a total of 787 and 769 ORFs for the Angomonas deanei and Strigomonas culicis endosymbionts, respectively, and indicate that these organisms hold a common ancestor related to the Alcaligenaceae family. Importantly, both symbionts contain enzymes that complement essential host cell biosynthetic pathways, such as those for amino acid, lipid and purine/pyrimidine metabolism. These findings increase our understanding of the intricate symbiotic relationship between the bacterium and the trypanosomatid host and provide clues to better understand eukaryotic cell evolution.

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The present study reports the first outbreak of autochthonous canine visceral leishmaniasis in Florianópolis, Santa Catarina, southern Brazil. Following the report of two cases of CVL, the Control Center of Zoonotic Diseases conducted a serological survey by ELISA and IFAT assays in seven districts of the Santa Catarina Island. Eleven seropositive dogs of autochthonous transmission were used in the present study. Infection by Leishmania sp. was confirmed by parasitological examination of bone marrow, liver, spleen and lymph nodes, culture in Schneider's medium and PCR. Leishmania sp. isolates were characterized by PCR-RFLP and hybridization with specific probes, allowing for the identification of Leishmania infantum. Autochthonous transmission of this disease in an area with high tourist traffic presents a major public health concern and signifies the emergence of an important zoonosis in southern Brazil. Therefore, the implementation of surveillance and control measures is imperative to prevent the spread of the disease among the canine population as well as transmission to the human population.

O presente estudo relata o primeiro surto autóctone de leishmaniose visceral canina (LCV) em Florianópolis, Santa Catarina, Brasil. Durante levantamento soro-epidemiológico realizado pelo Centro de Controle de Doenças Zoonóticas (CCZ) envolvendo 2.124 cães, 29 (1,37%) foram soropositivos para VL (ELISA + RIFI). Onze cães positivos por transmissão autóctone foram utilizados no presente estudo. A confirmação da infecção por Leishmania sp. foi realizada pelo exame parasitológico da medula óssea, fígado, baço e linfonodos, cultura em meio Schneider e PCR. Os isolados de Leishmania sp. foram caracterizados por PCR-RFLP e hibridação com sondas específicas, permitindo a identificação de Leishmania infantum. A transmissão autóctone da LCV em uma área com grande fluxo turístico como Florianópolis representa um preocupante risco à saúde pública e o surgimento de uma importante zoonose no sul do Brasil. Neste contexto, a implementação de medidas de vigilância e controle da doença são fundamentais para evitar a propagação da doença entre a população canina, bem como a transmissão para a população humana.

Assuntos

RESUMO

The present study reports the first outbreak of autochthonous canine visceral leishmaniasis in Florianópolis, Santa Catarina, southern Brazil. Following the report of two cases of CVL, the Control Center of Zoonotic Diseases conducted a serological survey by ELISA and IFAT assays in seven districts of the Santa Catarina Island. Eleven seropositive dogs of autochthonous transmission were used in the present study. Infection by Leishmania sp. was confirmed by parasitological examination of bone marrow, liver, spleen and lymph nodes, culture in Schneider's medium and PCR. Leishmania sp. isolates were characterized by PCR-RFLP and hybridization with specific probes, allowing for the identification of Leishmania infantum. Autochthonous transmission of this disease in an area with high tourist traffic presents a major public health concern and signifies the emergence of an important zoonosis in southern Brazil. Therefore, the implementation of surveillance and control measures is imperative to prevent the spread of the disease among the canine population as well as transmission to the human population.(AU)

O presente estudo relata o primeiro surto autóctone de leishmaniose visceral canina (LCV) em Florianópolis, Santa Catarina, Brasil. Durante levantamento soro-epidemiológico realizado pelo Centro de Controle de Doenças Zoonóticas (CCZ) envolvendo 2.124 cães, 29 (1,37%) foram soropositivos para VL (ELISA + RIFI). Onze cães positivos por transmissão autóctone foram utilizados no presente estudo. A confirmação da infecção por Leishmania sp. foi realizada pelo exame parasitológico da medula óssea, fígado, baço e linfonodos, cultura em meio Schneider e PCR. Os isolados de Leishmania sp. foram caracterizados por PCR-RFLP e hibridação com sondas específicas, permitindo a identificação de Leishmania infantum. A transmissão autóctone da LCV em uma área com grande fluxo turístico como Florianópolis representa um preocupante risco à saúde pública e o surgimento de uma importante zoonose no sul do Brasil. Neste contexto, a implementação de medidas de vigilância e controle da doença são fundamentais para evitar a propagação da doença entre a população canina, bem como a transmissão para a população humana.(AU)

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The antiherpes effects of the crude extract obtained from Ilex paraguariensis leaves (yerba mate) and their purified fractions were investigated. The most active fraction was selected and assayed to determine the viral multiplication steps upon which it acted. In order to detect the major components of this fraction, thin layer chromatography (TLC) analysis was performed. The antiviral activity was evaluated against HSV-1 and HSV-2 by a viral plaque number reduction assay (IC(50) ) and the cytotoxicity by a MTT assay (CC(50) ). According to the obtained results, all tested samples showed antiherpes activity at noncytotoxic concentrations, and the ethyl acetate fraction was the most active (SI = CC(50) /IC(50) = 188.7 and 264.7 for HSV-1 and HSV-2, respectively). The results also demonstrated that this fraction exerts antiviral activity by the reduction of viral infectivity, the inhibition of virus entry into cells and cell-to-cell virus spread, as well as by the impaired levels of ICP27, ICP4, gD and gE proteins of HSV-1. The TLC analysis showed that this fraction contains monodesmosidic triterpenoid saponins, matesaponin-1 (a bidesmosidic one), caffeic and chlorogenic acids and rutin, which suggests that they could act synergistically and be responsible for the detected antiherpes activity.

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Despite the economic impact of the infectious myonecrosis virus (IMNV) on shrimp farms in several countries, no method for immunological detection is currently available. With the aim of developing immunodiagnostic methods for IMNV detection in infected shrimps, a recombinant fragment of the IMNV major capsid protein gene encoding amino acids 105-297 (rIMNV105₋297 was heterologously expressed in Escherichia coli and used to immunize Balb/c mice, generating monoclonal antibodies (MAbs). Six hybridomas were obtained, and four of these recognized the presence of IMNV in tissue homogenates from naturally infected shrimps by immunodot blot assay. Among these MAbs, three were able to detect a ~100-kDa protein, which corresponds to the predicted mass of the IMNV major capsid protein, as well as viral inclusion bodies in muscle fibroses by western blot and immunohistochemistry. Two MAbs showed high specificity and sensitivity, showing no cross-reaction with healthy shrimp tissues in any assays, indicating their usefulness for IMNV detection.

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Two species of the genus Trypanosoma infective to humans have been extensively studied at a cell and molecular level, but study of the third, Trypanosoma rangeli, remains in relative infancy. T. rangeli is non-pathogenic, but is frequently mistaken for the related Chagas disease agent Trypanosoma cruzi with which it shares vectors, hosts, significant antigenicity and a sympatric distribution over a wide geographical area. In this study, we present the T. rangeli gene expression profile as determined by the generation of ESTs (Expressed Sequence Tags) and ORESTES (Open Reading Frame ESTs). A total of 4208 unique high quality sequences were analyzed, composed from epimastigote and trypomastigote forms of SC-58 and Choachí strains, representing the two major phylogenetic lineages of this species. Comparative analyses with T. cruzi and other parasitic kinetoplastid species allowed the assignment of putative biological functions to most of the sequences generated and the establishment of an annotated T. rangeli gene expression database. Even though T. rangeli is apathogenic to mammals, genes associated with virulence in other pathogenic kinetoplastids were found. Transposable elements and genes associated mitochondrial gene expression, specifically RNA editing components, are also described for the first time. Our studies confirm the close phylogenetic relationship between T. cruzi and T. rangeli and enable us to make an estimate for the size of the T. rangeli genome repertoire ( approximately 8500 genes).

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Diesel fuel is a potential contaminant of estuarine and mangrove areas, particularly because it is the main fuel used in small boats and larger vessels. The aim of this work was to identify genes differentially expressed in the liver of Poecilia vivipara (Guppy) exposed to 10% diesel fuel water accommodated fraction (WAF), employing the subtractive suppressive hybridization (SSH) method. The results showed 27 differentially expressed gene fragments, 12 up-regulated and 15 down-regulated. Among the up-regulated genes were CYP1A, UDPGT1a, ABCC4, Methyltransferase and Apolipoprotein A1. Down-regulated genes included Vitellogenins, C1 Inhibitor and Complement Component 3c. The identified genes are associated with different metabolic functions like biotransformation, membrane transport and immune system, indicating the susceptibility and/or molecular responses of this organism to the toxic effects elicited by diesel fuel WSF.

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BACKGROUND: Human infection by the pork tapeworm Taenia solium affects more than 50 million people worldwide, particularly in underdeveloped and developing countries. Cysticercosis which arises from larval encystation can be life threatening and difficult to treat. Here, we investigate for the first time the transcriptome of the clinically relevant cysticerci larval form. RESULTS: Using Expressed Sequence Tags (ESTs) produced by the ORESTES method, a total of 1,520 high quality ESTs were generated from 20 ORESTES cDNA mini-libraries and its analysis revealed fragments of genes with promising applications including 51 ESTs matching antigens previously described in other species, as well as 113 sequences representing proteins with potential extracellular localization, with obvious applications for immune-diagnosis or vaccine development. CONCLUSION: The set of sequences described here will contribute to deciphering the expression profile of this important parasite and will be informative for the genome assembly and annotation, as well as for studies of intra- and inter-specific sequence variability. Genes of interest for developing new diagnostic and therapeutic tools are described and discussed.

RESUMO

This study shows the characterization of the histone H2A intergenic region sequences (H2A IR) from Trypanosoma rangeli KP1(+) and KP1(-) strains isolated from distinct hosts and geographic regions. Also, a comparative unweighted pair-group method using arithmetic averages (UPMGA) analysis with polymerase chain reaction profiles of the 24Salpha rDNA and the miniexon genes was performed. Detailed H2A IR sequence analysis revealed a discrete size polymorphism among T. rangeli strains and the presence of single-nucleotide polymorphisms and minisatellite repeats, exclusively allowing an interspecific differentiation from T. cruzi strains representing the main parasite lineages. Differently from the H2A IR, UPMGA analysis of the 24Salpha rDNA and the miniexon genes profiles clearly branched T. rangeli strains into KP1(-) and KP1(+) lineages, clustering separately the Brazilian and Colombian KP1(-) strains. The evolutionary implications of these findings are discussed.

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