A new haemosporidian parasite from the Red-legged Seriema Cariama cristata (Cariamiformes, Cariamidae).

Haemoproteids (Haemosporida, Haemoproteidae) are a diverse group of avian blood parasites that are transmitted by hematophagous dipterans. In this study, we describe Haemoproteus pulcher sp. nov. from a Red-legged Seriema (Cariama cristata) in southeast Brazil. Analysis of the mitochondrial cytb gene indicates this parasite is closely related to Haemoproteus catharti (from Turkey Vulture, Cathartes aura) and the unidentified haemosporidian lineages PSOOCH01 (from Pale-winged Trumpeter, Psophia leucoptera) and MYCAME08 (from Wood Stork, Mycteria americana). This group of parasites appears to represent an evolutionary lineage that is distinct from other Haemoproteus spp., being instead more closely related to Haemocystidium spp. (from reptiles), Plasmodium spp. (from reptiles, birds, and mammals) and other mammal-infecting haemosporidians (Nycteria, Polychromophilus, and Hepatocystis). Current evidence suggests that parasites of this newly discovered evolutionary lineage may be endemic to the Americas, but further studies are necessary to clarify their taxonomy, life cycle, vectors, hosts, geographic distribution and host health effects. Additionally, it should be borne in mind that some PCR protocols targeting the cytb gene might not reliably detect H. pulcher due to low primer affinity.

Capybara (Hydrochoerus hydrochaeris) exposure to Rickettsia in the Federal District of Brazil, a non-endemic area for Brazilian spotted fever.

In this study, whole blood samples and ticks were collected from 57 capybaras in recreational areas in the Federal District, Brazil, aiming to investigate the presence of Rickettsia spp. using polymerase chain reaction (PCR) and indirect immunofluorescence (IFAT) assays. None of the capybara blood samples yielded rickettsial DNA by PCR. Among 55 capybara serum samples tested by IFAT, 53 (96.3%) reacted to Rickettsia spp. Among these, 21 (39.6%) identified the R. bellii antigen as the probable antigen involved in a homologous reaction (PAIHR), whereas 2 (3.8%) identified the R. parkeri antigen. Ticks collected from capybaras were identified as 173 Amblyomma sculptum and 410 A. dubitatum, in addition to nine Amblyomma spp. larvae. A sample of 231 ticks was subjected to DNA extraction and PCR for Rickettsia species. None of 122 A. sculptum yielded rickettsial DNA. Molecular evidence of R. bellii was found in 25/108 (23.1%) and of Rickettsia sp. strain Cooperi (R. parkeri-like agent) in 2/108 (1.9%) of the A. dubitatum samples. These results suggest a greater exposure to R. bellii in these capybara populations, in addition to a more significant number of A. dubitatum, which might characterize the Federal District region as not endemic for Brazilian spotted fever.

Estudo das proteínas componentes da junção compacta na evolução do carcinoma epidermóide do lábio / Study of tight junction proteins on the squamous cell lip carcinoma evolution

Queilite actiníca é uma doença que afeta geralmente o lábio inferior e é causada por exposição excessiva a radiação solar. Esta doença abriga no epitélio do lábio, alterações histológicas que são consideradas atualmente como a fase inicial, incipiente do carcinoma epidermóide. As junções compactas são importantes no processo de transporte paracelular, servindo de barreira a passagens de íons, água e macromoléculas, mantendo a polaridade celular. Uma das principais moléculas destas junções compactas são as claudinas que são essenciais na formação das junções compactas. Durante o processo de tumorigênese as moléculas destas junções podem sofrer alterações em sua expressão e distribuição no tecido, tornando-se assim, importantes moléculas na compreensão do processo de invasão tumoral. Para avaliar a expressão das claudinas em casos de queilite actínica e carcinoma epidermóide de lábio foi utilizada a técnica de imunoistoquímica em 100 casos. O padrão de expressão foi avaliado de forma qualitativa em cada caso. O padrão de marcação encontrado para claudina-1, -3, -5 e -7 foi de positividade nas áreas correspondentes ao terço inferior, médio e superior do epitélio em lesões de neoplasia intraepitelial de baixo grau, o padrão para claudina-11 apresentou marcação no terço inferior e médio. Em casos de neoplasia intraepitelial de alto grau observou-se ausência de marcação para claudina-1, -3, e -7 no terço inferior do epitélio com positividade no terço médio e superior; claudina-5 notou-se marcação em todos os terços do epitélio, claudina-11 observou-se marcação no terço inferior e médio. Em casos de carcinoma epidermóide superficialmente invasivo observa-se ausência de marcação nas áreas de fronte de invasão e marcação nos terços médio e superior do epitélio para claudina-1. -3 e -7, claudina -11 apresentou marcação apenas no terço médio e claudina -5 apresentou marcação no fronte de invasão e no terço médio e superior do epitélio. Casos de carcinoma epidermóide invasivo apresentaram ausência de marcação no fronte de invasão e marcação nas áreas centrais para as claudina -1, -3, -7 e -11, claudina -5 apresentou marcação citoplasmática no fronte de invasão e nas áreas centrais dos blocos tumorais. Concluindo, todas as fases da queilite actínica, desde as que abrigam alterações epiteliais precoces até o carcinoma epidermóide, apresentam alterações nos padrões das claudinas, com ênfase na diminuição da expressão das claudinas 1, 3, 7 e 11.

Actinic cheilits is a pathologic condition that usually affects the lower lip and is caused by excessive exposure to solar radiation; it corresponds to the early, incipient phase of squamous cell carcinoma. Tight junctions are important on the paracellular transport process; it functions as a barrier to ions, water and macromolecules to maintain the cellular polarity. Claudins are the key molecules of tight junctions, regarded as essential on the formation of the tight strands. During the tumorigenesis process these proteins may present altered expression and distribution throughout the tissue, therefore, considered important molecules in the invasion process of cancer cells. To evaluate the claudin expression in cases of actinic cheilits and squamous cell carcinoma of the lip immunohistochemistry technique was perfomed in 100 cases that were analysed in light microscopy. Claudins -1, -3, -5, and -7 were positive on the areas corresponding to medium, inferior and superior thirds of the epithelium in lesions of intraepithelial neoplasia of low grade; claudin-11 it was observed in the inferior and medium third of the epithelium. In cases of high grade intraepithelial neoplasia the absence of claudins -1, -3 and -7 on the inferior third of the epithelium was observed, and expression of this molecule was seen in the medium and superior thirds; claudin -5 was detected on all epithelial layers and claudin-11 showed positivity on the inferior and medium thirds. In cases of superficially invasive squamous cell carcinoma of the lip the molecule was not expressed in the invasive front of the tumor islands but immunoreactivity was detected on the central areas for claudins -1, -3 and -7; claudin -11 showed positivity only on the medium third and claudin-5 showed immunoreactivity in the invasive front and in central areas. Cases of invasive squamous cell carcinoma showed absence of claudins -1, -3, -7 and -11 in the invasive front, claudin -5 showed cytoplasmatic positivity on the invasive front and on central areas of the tumor islands. In conclusion, altered expression of some specific claudins subtypes are present in actinic cheilitis from its incipient phase throughout invasive squamous cell carcinoma.