Phylogenetic studies on trypanosomatid barcode using V7V8 SSU rRNA and gGAPDH gene sequences have provided support for redefining some trypanosomatid species and positioning new isolates. The genus Leishmania is a slow evolving monophyletic group and including important human pathogens. The phylogenetic relationships of this genus have been determined by the natural history of its vertebrate hosts, vector specificity, clinical manifestations, geographical distribution and molecular approaches using different markers. Thus, in an attempt to better understand the phylogenetic relationships of Leishmania species, we performed phylogenetic analysis on trypanosomatid barcode using V7V8 SSU rRNA and gGAPDH gene sequences among a large number of Leishmania species and also several Brazilian visceral Leishmania infantum chagasi isolates obtained from dogs and humans. Our phylogenetic analysis strongly suggested that Leishmania hertigi and Leishmania equatoriensis should be taxonomically revised so as to include them in the genus Endotrypanum; and supported ancient divergence of Leishmania enriettii. This, together with recent data in the literature, throws light on the discussion about the evolutionary southern supercontinent hypothesis for the origin of Leishmania ssp. and validates L. infantum chagasi from Brazil, thus clearly differentiating it from L. infantum, for the first time.

In the order Chiroptera, more than 30 trypanosome species belonging to the subgenera Herpetosoma, Schizotrypanum, Megatrypanum, and Trypanozoon have been described. The species Trypanosoma cruzi , Trypanosoma cruzi marinkellei, and Trypanosoma dionisii are the most common in bats and belong to the Schizotrypanum subgenus. Bats from 2 different biomes, Pantanal and Amazonia/Cerrado in the state of Mato Grosso, Brazil, were evaluated according to the presence of trypanosome parasites by means of hemoculture and PCR in primary samples (blood samples). A total of 211 bats from 20 different species were caught and the trypanosome prevalence, evaluated through hemoculture, was 9.0% (19), 15.5% (13), and 4.8% (6) in the municipalities of Confresa (Amazonia/Cerrado biome) and Poconé (Pantanal biome). Among the 123 primary samples obtained from the bats, only 3 (2.4%) were positive. Phylogenetic analysis using trypanosomatid barcoding (V7V8 region of SSU rDNA) identified all the isolates and primary samples as T. c. marinkellei. The sequences of the isolates were segregated according to the bat host genus or species and suggest that co-evolutionary patterns exist between hosts and parasites. Further studies in different Brazilian regions and biomes need to be conducted in order to gain real understanding of the diversity of trypanosomes in bats.

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This study evaluated exposure and infection by tick-borne agents (Babesia vogeli, Ehrlichia canis and Rickettsia spp.) in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of Chapadinha, state of Maranhão, northeastern Brazil, using molecular and serological methods. Overall, 16.1% of the sampled dogs (52/322) were seroreactive to B. vogeli, with endpoint titers ranging from 40 to 640. For E. canis, 14.6% of the dogs (47/322) were seroreactive, with endpoint titers from 80 to 163,840. Antibodies reactive to at least one of the five species of Rickettsia were detected in 18.9% of the dogs (61/322), with endpoint titers ranging from 64 to 4,096. High endpoint titers were observed for Rickettsia amblyommii. Three (0.9%) and nine (2.8%) canine blood samples were PCR-positive for Babesia spp. and E. canis. The ticks collected from urban dogs were all Rhipicephalus sanguineus sensu lato, whereas the rural dogs were infested by R. sanguineus s.l, Amblyomma cajennense sensu lato and Amblyomma ovale. One A. ovale tick was found to be infected by Rickettsia bellii. This study provides an epidemiological background for controlling and preventing canine tick-borne diseases in a neglected region of Brazil.Keywords: Ticks, tick-borne pathogens, hemoparasites. ResumoEste estudo avaliou por métodos sorológicos e moleculares a exposição e infecção por agentes transmitidos por carrapatos (Babesia vogeli, Ehrlichia canis, and Rickettsia spp.)

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Objetivou-se determinar a ocorrência de Babesia canis vogeli em cães e no carrapato vetor de ambiente urbano e rural da microrregião de Imperatriz, mesorregião do Oeste Maranhense, verificando-se os possíveis fatores de risco associados à infecção por esse agente. Foram coletadas amostras de sangue e espécimes de carrapatos de 300 cães provenientes da área urbana e rural da microrregião de Imperatriz. Foram realizadas extração do DNA do sangue e dos carrapatos. Posteriormente, as amostras foram submetidas a ensaios de reação em cadeia pela polimerase, utilizando-se oligonucleotídeos iniciadores subespécieespecífico para B. c. vogeli. A PCR a partir de amostras de sangue revelou que 3,33% (10/300) dos cães estavam positivos para B. c. vogeli, sendo que 1,0% (3/300) era da área urbana e 2,33% (7/300) da área rural. Não foram verificadas associações entre ambiente de coleta, grupo racial, sexo e controle de carrapatos; contudo, a taxa de positividade para B. c. vogeli foi maior entre os cães jovens. Os carrapatos coletados foram identificados como Rhipicephalus sanguineus, sendo seis (2,56%) positivos para B. c. vogeli, com 1,28% (3/235) provenientes de cães da área urbana e 1,28% (3/235) de cães da área rural. Este estudo confirmou a presença de B. c. vogeli em cães e em R. sanguineus na área urbana e rural da microrregião de Imperatriz-MA.

The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5, HOXD10 and HOXD11) in OSCC that may play a significant role in the pathogenesis of these tumors. Moreover, since lower levels of HOXA5 predict poor prognosis, this gene may be a novel candidate for development of therapeutic strategies in OSCC.

This study evaluated for the first time, ectoparasite infestations on dogs from urban and rural areas of the continental land of the state of Maranhão, northeastern Brazil. In total, 622 dogs were examined for ectoparasite infestations. Overall, 392 (63.0%) were infested with ectoparasites, 154 (51.3%) of 300 urban dogs and 238 (73.9%) of 322 rural dogs. Five species of ectoparasites were found, three ticks [Rhipicephalus sanguineus (Latreille), Amblyomma ovale Koch, and Amblyomma cajennense (F.)], one flea [Ctenocephalides felis (Bouché)], and one louse [(Heterodoxus spininger (Enderlein)]. The frequency of infestation by R. sanguineus tended to be higher in urban than in rural areas, whereas infestations by Amblyomma ticks and C. felis fleas tended to be higher among rural dogs. Louse (H. spininger) infestations were similarly low among all areas. Mixed infestations by at least two species of ectoparasites on the same dog were significantly more frequent on rural than on urban dogs. The most frequent mixed infestation was by R. sanguineus and C. felis, found on 11.4% of the dogs. Further studies are warranted to evaluate canine vector-borne agents in Maranhão, especially because most of the ectoparasites here reported are vectors of major vector-borne diseases, including zoonoses of continental importance.