Transmission of visceral leishmaniasis in dogs in a risk area of the metropolitan region of Belo Horizonte, Minas Gerais, Brazil / Transmissão da leishmaniose visceral em cães em área de risco da Região Metropolitana de Belo Horizonte, Minas Gerais, Brasil

Visceral leishmaniasis (VL) has spread rapidly across cities in the metropolitan region of Belo Horizonte. The aim of this study was to investigate VL dynamics in a prospective cohort study of dogs in Juatuba, between 2010 and 2011, to confirm the incidence of Leishmania infantum, and to assess possible risk factors associated with infection. An observational and prospective closed cohort study was performed using serology testing in dogs, randomly selected from the whole municipality. All seronegative dogs, or dogs with inconclusive results were monitored using indirect immunofluorescence (IIF) at 6-month intervals. The dog's owners completed a semi-structured questionnaire to assess possible causal factors of seroconversion, and the responses were assessed using logistic regression. The canine incidence coefficient was 206/1,000 dogs per year (CI: 178-238), and a cluster was identified in an area with a high concentration of seropositive dogs, but a low overall canine population. Large dogs were identified as a risk factor and the following variables were identified as protection factors: dogs aged over 4 years, daily peridomicile cleaning, and better socioeconomic conditions. VL is spreading over a large area in Juatuba in a short period of time.(AU)

A leishmaniose visceral (LV) expandiu-se de forma rápida e extensa pelos municípios da Região Metropolitana de Belo Horizonte. Objetivou-se estudar a dinâmica da LV em uma coorte prospectiva de cães em Juatuba, entre 2010 e 2011, para verificar a incidência e fatores de risco associados à infecção por Leishmania infantum. Foi feito um estudo observacional e prospectivo de coorte fechada por meio de análise sorológica em cães selecionados aleatoriamente em todo o município, com acompanhamento semestral dos resultados soronegativos e indeterminados na imunofluorescência indireta (IFI). Usou-se questionário semiestruturado junto aos proprietários de cães para avaliação da soroconversão e dos fatores determinantes a essa, por meio da regressão logística. O coeficiente de incidência canina foi de 206/1000 cães.ano (IC: 178 - 238), e foi identificado cluster em área com elevada concentração de cães soropositivos, mas com baixa densidade populacional canina. A variável cão de porte grande foi identificada como fator de risco, e as variáveis idade do cão superior a quatro anos, limpeza diária do peridomicílio e melhores condições socioeconômicas como fatores de proteção. A infecção por LV está ocorrendo em curto período de tempo e com ampla distribuição em Juatuba.(AU)

Anatomical arrangement and distributionof the cerebral arterial circle in rats

The cerebral arterial circle is a polygonal shape-like arterial anastomosis placed in the brain base, whereit rounds the optic quiasm and the tuber cinereum, and also related to the interpeduncular fossa and theanterior perfurated substance. It is formed by the proximal parts of the anterior, middle and posterior cerebralarteries, and the right and left posterior communicating arteries. In order to describe the cerebral arterial circledisposition we investigated the brains of twenty rats. For each animal, the heart left ventricle was probed andacetone, distilled water at 37 °C and a solution of Neoprene Latex “450” stained with a specific red pigmentwere injected in sequence into it. To fix the brain in a better way, we isolated the head and made an apertureat the dorsal wall of the cranium and the whole specimen was fixed in a 15% formaldehyde solution. We tookoff the brain from the skull with the aid of a cold light source monocular magnifier. To take the photographicdata we used a semi-professional camera. The results showed that the cerebral arterial circle in rats is formedby branches of both internal carotid arteries and of the basilar artery, and is closed rostrally by the rostralcommunicating artery, and caudally by the right and left terminal branches of the basilar artery. We concludedfrom our data that the cerebral arterial circle in rats is compound by branches of both internal carotid arteriesand basilar artery, and that it is rostrally and caudally closed.

Production of L1 protein from different types of HPV in Pichia pastoris using an integrative vector

Human papillomavirus (HPV) infection is the most common sexually transmitted disease in the world and is related to the etiology of cervical cancer. The most common high-risk HPV types are 16 and 18; however, the second most prevalent type in the Midwestern region of Brazil is HPV-33. New vaccine strategies against HPV have shown that virus-like particles (VLP) of the major capsid protein (L1) induce efficient production of antibodies, which confer protection against the same viral type. The methylotrophic yeast Pichia pastoris is an efficient and inexpensive expression system for the production of high levels of heterologous proteins stably using a wild-type gene in combination with an integrative vector. It was recently demonstrated that P. pastoris can produce the HPV-16 L1 protein by using an episomal vector associated with the optimized L1 gene. However, the use of an episomal vector is not appropriate for protein production on an industrial scale. In the present study, the vectors were integrated into the Pichia genome and the results were positive for L1 gene transcription and protein production, both intracellularly and in the extracellular environment. Despite the great potential for expression by the P. pastoris system, our results suggest a low yield of L1 recombinant protein, which, however, does not make this system unworkable. The achievement of stable clones containing the expression cassettes integrated in the genome may permit optimizations that could enable the establishment of a platform for the production of VLP-based vaccines.

Simultaneous presence of bovine papillomavirus and bovine leukemia virus in different bovine tissues: in situ hybridization and cytogenetic analysis

Bovine papillomavirus (BPV) DNA sequences were detected in different tissues, in addition to epithelium. Cytogenetic abnormalities were observed in blood lymphocytes. The presence of more than one virus in a single tissue is a difficult aspect to evaluate, especially when the DNA sequences are detected in tissues that are not specifically targeted by the virus. BPV and bovine leukemia virus (BLV) are clastogenic, causing chromosome aberrations in peripheral blood lymphocytes. In the present study, we investigated the simultaneous presence of DNA sequences of both viruses and the possibility of vertical transmission and compared the types of chromosome aberrations related to viral action. BPV 1, 2, and 4 DNA sequences were found in three females of the herd and in their offspring. BLV DNA sequences were not detected in their progeny. A newborn calf that was negative for BLV infection showed specific chromosome rearrangements possibly related to the effect of infection with BPV.

Substituded pyrazolylhydrazones: a new class of platelet aggregation inhibitors

A series of 5-pyrazolylhydrazone derivates (I) were designed to be mixed hybrid isosteres of both BW-755C and CBS-1108 which belong to the class of dual cyclooxygenase and 5-lipoxygenase inhibitors. Pharmacological evaluation of some members of this series (Ia, 1-formy 1-3,4-methylenedioxy-6-nitrobenzene-5-(1-phenyl-3-methyl-4-nitropyrazolil)hydrazone; Ib, 2-formylfurane-5-(1-phenyl-3-methyll-4-nitropyrazolyl)hidrazone; Ic, (E)-2-(formylethenylfurane)-5-(1-phenyl-3-methyl-4-nitropyrazolyl)hydrazone showed that they inhibit the in vitro platelet aggregation of citrated platelet-rich rabbit plasma induced by ADP (5µM), collagen (5µg/ml) and arachidonic acid (100 µM). Compounds Ia and Ic at 100 µM concentration showed 49% and 58% inhibition, respectively, of ADP-induced aggregation. In the arachidonic acid-induced aggregation, compounds Ia and Ib at 100 µM concentration fully inhibited platelet aggregation. All compounds significantly inhibited the collagen-induced aggregation. In contrast, indomethacin (10 µM) showed 100% and 85% aggregation inhibition against arachidonic acid and collagen, respectivelym, and was inactive in the ADP- induced aggregation test. These results suggest that the structure-activity relationship in this series of compounds is dependent on the hydrazone moiety at position 5 of the pyrazole ring and on the distance between the aryl ring and the pyrazole ring and that the 2-furyl ring is at the optimal distance for the maximal activity

Antinociceptive property of new 4-acyl-arylhydrazone pyrazole compounds

A series of new 4-acyl-arylhydrazone pyrazole compunds were tested for antinociceptive activity using the inhibition of abdominal contortions induced by acetylcholine (4 mg/Kg, ip) in the mouse. Dipyrone was used for comparison of the antinociceptive potency of the compounds being tested. All drugs wee administered po in saline (dipyrone) or in propylene flycol 94-acyl-arylhydrazones). The maximum response induced by dipyrone (86% inhibition) was assigned an efficacy index of 1.0. Although none of the compounds had an efficacy index greater than 1.0, all three reached 1.0. The two most potent compounds, Wd1 and W1g, which also had an efficacy similar to that of dipyrone, contain a p-N(CH3)2 and m-OH,p-OCH3 group in the aromatic ring of the acyl-hydrazone, respectively. W1d presented the lowest antinociceptive ED50 in the series (1.41 mg/Kg) and was eleven times more potent than dypyrone (ED50 = 15.80 mg/Kg). Other substitutions at the para position had lower potency than W1d. The present results indicate that the introduction of a group at the para postion of the acyl-arylhydrazone ring increases the antinociceptive activity of these compounds to provide compounds of the same efficacy but greater potency than dipyrone to which these new compounds ara structurally related. Other assays of nociceptive activity are veing used to characterize the mechanism of action of the potential new drugs