Finding Aedes aegypti in a natural breeding site in an urban zone, Sao Paulo, Southeastern Brazil

ABSTRACT This is the description of how nine Aedes aegypti larvae were found in a natural breeding site in the Pinheiros neighborhood, city of Sao Paulo, SP, Southeastern Brazil. The record was conducted in December 2014, during an entomological surveillance program of dengue virus vectors, with an active search of potential breeding sites, either artificial or natural. Finding Ae. aegypti larvae in a tree hole shows this species’ ability to use both artificial and natural environments as breeding sites and habitats, which points towards the importance of maintaining continuous surveillance on this mosquito in all kinds of water-holding containers.

Basofilia e anisotropia nucleares em células de camundongo após tratamento com oxamniquine

Com o objetivo de se estudar a ação da oxamniquine, uma droga utilizada no tratamento da esquistossomose, sobre a cromatina de núcleos de células animais, foram estudados os padrões de basofilia e anisotropia nucleares em hepatócitos, em células do músculo cardíaco e em linfócitos de camundongos adultos jovens. A oxamniquine foi administrada por via oral (436 mg/kg) e preparados foram obtidos após diversos tempos de fornecimento da droga aos animais. Nos núcleos corados com azul de toluidina a pH 4,0, após digestão com RNAse, não se encontrou diferença quanto aos padrões de basofilia e anisotropia comparando-se animais tratados com controles. Demonstrou se assim que as moléculas de oxamniquine não se alojam no interior da dupla hélice do DNA, não alteram a sua conformação helicoidal nem se ligam aos grupos fosfatos livres desta macromolécula, diferindo, portanto, da atuação de outro esquistossomicida, o hycanthone.

Infeccion natural de Ptychophallus tristani (Crustacea: decapoda) con metacercarias de Paragonimus mexicanus (Trematoda) en Tabarcia de Mora, Costa Rica

Se determinó el grado de infección de los crustáceos Ptychophallus tristani presentes en una área endémica de Paragonimus mexicanus, encontrándose que de un total de 182 cangrejos, 161 resultaron positivos (88,5%) por metacercarias. Al comparar la infección entre machos y hembras no se encontró diferencias estadísticamente significativas y en relación a su tamaño se observó una relación directa entre tamaño y porcentaje y grado de infección. Se estableció que no existen diferencias significativas en relación a la época del año en que los cangrejos fueron capturados lo que epidemiológicamente es importante pues indica que las fuentes de infección permanecen potencialmente activas durante todo el año.

Replicação de sendai virus em células epiteliais primárias de camundongo

Células epiteliais primárias obtidas do trato respiratório de camundongos jovens foram infectadas com o Vírus Hemaglutinante do Japão (HVJ, Sendai Virus) e, a progénie viral, tratada ou não com tripsina foi titulada através do método de Imunofluorescência Indireta. A progénie de Sendai Virus obtida de células epiteliais primárias de camundongo apresentou um título considerável, demonstrando-se que há ativação das partículas virais, capazes de infectar células LLC-MK 2, nas quais, a progénie viral foi titulada.

Infecção natural de Equus caballus por Leishmania sp - São Paulo, Brasil (Breve comunicação científica)

E assinalado, pela primeira vez, o encontro de um cavalo (Equus caballus) infeclado por Leishmania sp, no Estado de São Paulo.

Natural Trypanosoma cruzi infection in dogs of endemic areas of the Argentine Republic

The population dynamics and the prevalence of chagasic infection of 352 dogs living in 108 rural houses infested by triatomines were studied. The region was divided into three sections according to increasing distances to an urban area. Each animal was identified by means of its particular characteristics and built, and its owners gave information about its habits. By means of xenodiagnosis, serology and ECG studies, prevalences of infection, parasitological-serological correlation, percentage of altered electrocardiographic outlines and percentage of houses with parasitemic dogs, were determined. The rural area showed a characteristic T. cruzi infection pattern and differences in the canine population parameters with respect to the other areas were observed: a higher proportion of puppies than adult dogs, a more sedentary population, higher prevalences of infection, as measured by xenodiagnosis, in dogs, and the highest proportion of bedroom insects infected with T. cruzi. It is assumed that the sedentary characteristics of the human population in that rural area impinge in the blood offer to the triatomine population, and the high percentage of parasitemic dogs of the area, contribute to the rise of "kissing ougs" infected with T. cruzi found in bedrooms.

Infeccion natural de Speothos venaticus (Carnivora: Canidae) por estadios adultos de Lagochilascaris sp.

Un ejemplar adulto macho de Speothos venaticus Lund, 1842 fue muerto accidentalmente en una vía de penetración rural, situada en la región Noroeste del Estado Bolívar, Venezuela, en el Municipio donde desde hace 16 años vive una paciente con lagochilascariasis. El animal conservado durante un mes por congelación y desprovisto de su piel y cabeza fue autopsiado, hallándose en la tráquea dos especímenes adultos hembras y grávidos de Lagochilascaris sp., los cuales presentaban algunas características morfológicas de sus partes blandas diferentes a Lagochilascaris minor Leiper, 1909; entretanto, distintivos estables como son la forma de los interlabios, la localización de la vulva y particularmente el tamaño y número de las depresiones de la cáscara de los huevos, inclinan a pensar que se trata de aquel parásito, a pesar de no haberse hallado vermes machos que permitiesen el estudio de las espículas y su ducto eyaculador. Fueron localizadas en cortes histológicos de laringe y tráquea profundamente situadas, secciones de formas degeneradas con características atribuíbles a Lagochilascaris sp.

Natural and experimental infection of planorbids from the Island of Santa Catarina (Brazil)

Studies on eight localities on the Island of Santa Catarina revealed the presence of three species of the molluscan family Planorbidae: Biomphalaria tenagophila, Drepanotrema cimex and Biomphalaria oligoza, the first one being naturally infected by Cercaria ocellifera, a furcocercaria with morphological characteristics of Cercaria caratinguensis, and by an unknown furcocercaria. Drepanotrema cimex was infected by a furcocercaria with characteristics of C. caratinguensis and by C. macrogranulosa. No natural infection was found in B. oligoza. B. tenagophila showed no susceptibility to the experimental infection by the BH-MG strain of Schistosoma mansoni from Belo Horizonte and maintained at laboratory in B. glabrata snails.

Diferenças nas propriedades adesivas de Staphylococcus saprophyticus a células HEp-2 e eritrócitos

S. saprophyticus é freqüentemente isolado de infecções do trato urinário de mulheres jovens e sexualmente ativas. Ao contrário de S. aureus, esta espécie não possui fatores de virulência bem definidos. O objetivo deste estudo é analisar a aderência de S. saprophyticus a células HEp-2 e eritrócitos de carneiro. As amostras foram isoladas a partir da urina de pacientes com infecção urinária. Foram realizados testes de hemaglutinação, aderência a células HEp-2 e a capacidade de carboidratos específicos inibirem as interações entre estes tipos celulares e S. saprophyticus. A maioria das cepas se mostrou hemaglutinante e sensível a inibição da hemaglutinação pela manose (100mM). Foram verificados altos níveis de aderência às células HEp-2. As diferenças em especificidade e nível de aderência do microrganismo a células de HEp-2 e eritrócitos sugerem a participação de diferentes adesinas nos processos de interações celulares.

The ecology of Triatoma sordida in natural environments in two different regions of the state of Minas Gerais, Brazil

A study was undertaken about T. sordida in the natural environment in two different regions of the state of Minas Gerais: Itapagipe (Triângulo), an area of cerrado modified by the formation of fields of pasture and agriculture, and Mato Verde (north) an area of transition between caatinga and cerrado with profound deforestation in the last years due to the expansion of cotton cultivation. In both regions the principal ecotopes identified were hollow trees and the bark of live or dead trees, where the occurrence of a food source is not frequent. In this environment, the triatomines utilize various food sources; opposums appear to represent an important source of infection. In the north of Minas, a greater concentration of reservoirs and vectors was observed than in the Triángulo which could explain the higher level of infection of the triatomines in the north. Close attention to the process of domiciliation of T. sordida in the north of Minas is recommended where an extensive intervention by man in the natural environment has occurred and where a rise in the population of triatomines in the peridomestic environment has been observed in recent years.

Evaluation of the resistance to Schistosoma mansoni infection in Nectomys squamipes (Rodentia: Cricetidae), a natural host of infection in Brazil

The development of resistance in three stages throughout an active infection (pre-ovular, acute and initial chronic stages) was studied, comparing the total number of adult worms recovered from the reinfected group and the control groups. It was shown that Nectomys squamipes was unable to develop resistance in the tested conditions and, on the other hand, reinfection in the pre-ovular period of the parasite led the rodent to present the phenomenonacilitation, with reduction of natural resistance and an increase in the parasite load. These results suggest the existence of other forms of immunity diverse from the concomitant immunity in the host-parasite relationship, according to the employed model.

Evidences against a significant role of Mus musculus as natural host for Angiostrongylus costaricensis

Wild rodents have been described as the most important hosts for Angiostrongylus costaricensis in Central America and southern Brazil. Sinantropic rodents apparently do not play a significant role as natural hosts. A search for natural infection failed to document worms in 14 mice captured in the house of a patient with diagnosis of abdominal angiostrongylosis and experimental infection of a "wild" Mus musculus strain and groups of albino Swiss mice were carried out. Mortality was not significantly different and varied from 42% to 80% for Swiss mice and from 26% to 80% for "wild" mice. The high mortality of a "wild" M. musculus infected with A. costaricensis was very similar to what is observed with most laboratory mice strains. These data may be taken as indications that M. musculus is not a well adapted host for A. costaricensis, although susceptibility was apparently higher with "wild" populations of M. musculus as compared to Swiss strain.

IgG recognizing 21-24 kDa and 30-33 kDa tachyzoite antigens show maximum avidity maturation during natural and accidental human toxoplasmosis

We describe the avidity maturation of IgGs in human toxoplasmosis using sequential serum samples from accidental and natural infections. In accidental cases, avidity increased continuously throughout infection while naturally infected patients showed a different profile. Twenty-five percent of sera from chronic patients having specific IgM positive results could be appropriately classified using exclusively the avidity test data. To take advantage of the potentiality of this technique, antigens recognized by IgG showing steeper avidity maturation were identified using immunoblot with KSCN elution. Two clusters of antigens, in the ranges of 21-24 kDa and 30-33 kDa, were identified as the ones that fulfill the aforementioned avidity characteristics.