Nadja Lima Pinheiro

Diversidade de criadouros e tipos de imóveis freqüentados por Aedes albopictus e Aedes aegypti

OBJECTIVE To assess the diversity of oviposition containers and buildings where females of Aedes albopictus and Aedes aegypti can be found. METHODS A study was carried out in the city of Rio de Janeiro, Southern Brazil, between 2002 and 2003. Larvae in different types of buildings were investigated, and immature forms found were then sent to the laboratory for identification. The larval frequency for both mosquitoes was estimated in the oviposition containers available. The Breteau index and the building infestation index were calculated and differences were tested using the Chi-square test. RESULTS The types of buildings that were positive for Aedes albopictus and Aedes aegypti were: dwellings (83.9%); churches, schools, clubs (6.8%); vacant land (6.4%); and businesses (2.8%). Of 9,153 larvae collected, 12.0% were Aedes albopictus and 88.0% were Aedes aegypti. Aedes albopictus were mostly found in drains (25.4%); cans, bottles, empty bottles (23.9%); and plant vases (16.2%). Aedes aegypti was much more frequently found than Aedes albopictus (chi(2)=145.067; p<0.001). Both species were significantly more frequent in artificial than in natural oviposition containers (chi(2)=31.46; p<0.001). The building infestation index and Breteau index for Aedes albopictus were 0.3% and 0.28% in 2002 and 0.4% and 0.5 in 2003, respectively. For Aedes aegypti, they were 1.0%, 1.16 in 2002 and 3.5% and 4.35 in 2003, respectively. CONCLUSIONS The present study assessed the frequencies of Aedes albopictus and Aedes aegypti females in various types of oviposition containers and types of buildings. The abundant availability of artificial containers in dwellings, associated with the capacity of Ae. albopictus to be also found in natural oviposition containers, has greatly contributed for their gradual adaptation to human environment.

Correlação morfométrica do ovário de fêmeas bovinas em diferentes estádios reprodutivos

The aim of this study was to evaluate morphometric characteristics of bovine ovaries recovered on different reproductive stages. The ovaries used (N=200) were recovered at slaughterhouses and sent to the laboratory, were the size of the ovary, of follicles and of corpus luteum were measured. The pairs of ovaries were classified according to the reproductive stage, and to the estrous cycle or pregnancy stages of the animals from which they were recovered. There was a difference (P 0,05) on organ size between animals presenting estrous cycles or pregnancy, but pregnant cows presented larger corpora lutea and smaller diameter of the largest follicle (P<0,05). Evaluated parameters were affected by estrous cycle and pregnancy stages (P<0,05). There was a significant correlation between ovary and corpus luteum sizes in the animals presenting estrous cycles (R=0.69; P<0,001). In conclusion, ovarian morphologic characteristics changes according to the reproductive stages, could be used as parameters for clinic and functional evaluations of the organ.

Molecular characterization of Trypanosoma cruzi sylvatic isolates from Rio de Janeiro, Brazil

Trypanosoma cruzi, the etiologic agent of Chagas disease, presents considerable heterogeneity between isolated populations within the wild and domestic cycles. By using multiplex polymerase chain reaction based on the mini-exon gene, characterization was performed on seven samples isolated from specimens of Triatoma vitticeps that had been collected from the locality of Triunfo in the municipality of Santa Maria Madalena, state of Rio de Janeiro, Brazil. The samples SMM10, SMM53, SMM88, and SMM98 (area A) and SMM36 and SMM82 (area B) revealed the presence of 150 base pairs, corresponding to the zymodeme III (Z3). Our study suggested that one isolate (SMM1) presents a mixed genotype associated with Z3 and TcII. The typing of isolates of T. cruzi has the main aim of identifying strains with different epidemiological and/or clinical characteristics of Chagas disease. Our results corroborate other descriptions in the literature and contribute towards the knowledge and records of the profile of some additional wild isolates of T. cruzi in regions not yet affected by the disease.

Immunocytochemical study of the distribuition of endocrine cells in the pancreas of the Brazilian sparrow species Zonotrichia Capensis Subtorquata (Swaison, 1837)

In the present study, we investigated types of pancreatic endocrine cells and its respective peptides in the Brazilian sparrow species using immunocytochemistry. The use of polyclonal specific antisera for somatostatin, glucagon, avian pancreatic polypeptide (APP), YY polypeptide (PYY) and insulin, revealed a diversified distribution in the pancreas. All these types of immunoreactive cells were observed in the pancreas with different amounts. Insulin-Immunoreactive cells to (B cells) were most numerous, preferably occupying the central place in the pancreatic islets. Somatostatin, PPA, PYY and glucagon immunoreactive cells occurred in a lower frequency in the periphery of pancreatic islets.

Histological Description of Morphogenesis of the Gastroesophageal Mucosa of Gallus gallus domesticus (Linnaeus, 1758)

La morfogenesis de la mucosa gastroesofagica implica alteraciones morfologicas relacionadas con su estructura y la funcion de cada segmento. El presente estudio describe la histogenesis del epitelio secretor mucinoso y de las glandulas del esofago, molleja y proventriculo del pollo (G. gallus), ademas de identificar los cambios em el patron de secrecion de glicocosaminoglicanos (GAGs). Se utilizaron treinta y ocho embriones de pollo. El material recogido fue procesado de acuerdo a la rutina histologica y posteriormente las secciones se tinieron con hematoxilina-eosina para su analisis histologico, con tricromico de Gomori para identificar el tejido conectivo y las fibras de colageno y con PAS y AB pH 2,5 para el analisis GAGs neutro y acido. En una etapa avanzada de desarrollo de los embriones, se pudo obervar en la pared del esofago cuatro capas: mucosa, submucosa, muscular y serosa, mientras que el proventriculo y molleja se muestra constituida por tres capas: mucosa, muscular y serosa. En los tres segmentos de la superficie, el epitelio se identifico como mucinoso y en el esofago solo en la etapa inicial de desarrollo. Las glandulas del proventriculo se empiezan a formar en las primeras etapas de desarrollo, mientras que en las glandulas tubulares de la molleja comienzan su solo despues del dia 15. Las diferencias en la produccion de GAGs en estas regiones del tracto digestivo estan relacionadas con las etapas de desarrollo, las funciones y necesidades fisiologicas de cada segmento del cuerpo y se adapta gradualmente a la vida despues de la eclosion.

An immunocytochemical study of the endocrine cells in the stomach and duodenum of Zonotrichia capensis subtorquata (Passeriformes, Emberizidae)

The main purpose of this study was to evaluate the regional distribution pattern and relative frequency of some endocrine cells in the three portions of the gastrointestinal tract (GIT)--the proventriculus, gizzard and duodenum- of the rufous-collared sparrow (Zonotrichia capensis subtorquata), by immunohistochemical methods using six types of polyclonal antisera, specific for serotonin (5-HT), somatostatin (D cells), glucagon, motilin, polypeptide YY (PYY) and insulin. In the proventriculus, endocrine cells immunoreactive for all of these markers were observed. The somatostatin-immunoreactive cells were found with greater frequency, with the presence of cytoplasmic processes. In the gizzard, endocrine cells secreting somatostatin, 5-HT and PYY were detected, while those secreting glucagon and insulin were not. In the final part of the gizzard, endocrine cells secreting 5-HT were more frequent, and cells secreting somatostatin and insulin were not detected. All of the cell types studied were observed in the duodenum in different frequencies, except for cells immunoreactive for glucagon and insulin. The somatostatin-positive (D cells) were the most numerous, being more prevalent in the intestinal glands. The other endocrine cells were identified in smaller numbers, some of them located in the intestinal villi and Lieberkuhn glands. The finding of these cell types in the duodenum confirms their preferential location in the final portions of the principal segments of the digestive system and suggests control by feedback of its functions. In conclusion, some interesting distributional patterns of gastrointestinal endocrine cells were found in this species of sparrow.

Histologia e histoquímica do tubo digestório de Phrynops geoffroanus (Testudines, Chelidae)

Phrynops geoffroanus e o quelonio onivoro com mais ampla distribuicao geografica na America do Sul. Este trabalho descreve a histologia e histoquimica do tubo digestorio desta especie, relacionando as caracteristicas dos orgaos com seu habito alimentar. O esofago, estomago e intestino de quatro especimes foram fixados em formol 10% e incluidos em parafina por tecnica histologica de rotina. Depois, cortes de 5 µm de espessura foram corados com hematoxilina-eosina (HE), acido periodico de Schiff (PAS) e alcian blue (AB) pH 0.4 e 2.5. O tubo e formado pelas camadas mucosa, submucosa, muscular e adventicia ou serosa. A mucosa do esofago e do estomago e revestida pelo epitelio simples cilindrico com celulas mucossecretoras, onde estao inseridas glândulas intraepiteliais na porcao do esofago e fossetas gastricas desembocando em glândulas no estomago. O estomago divide-se em anterior, medio e posterior, de acordo com a profundidade das fossetas e a concentracao de glândulas gastricas. O intestino e revestido pelo epitelio simples cilindrico com borda estriada e celulas caliciformes e divide-se em anterior e posterior, de acordo com o padrao de dobramentos da mucosa e o numero de celulas caliciformes. Reatividade ao PAS e AB e observada em todo o tubo. Fibras musculares lisas estao presentes na camada mucosa de todos os segmentos. A camada muscular e formada por duas subcamadas de musculo liso, exceto na porcao posterior do estomago. Este estudo ajudara no entendimento da fisiologia digestiva da especie investigada e fornecera dados para analises comparativas com outros quelonios.

Structural study of the salivary glands of Anocentor nitens (Acari: Ixodidae) during the feeding cycle

The salivary glands of Anocentor nitens (Neumann, 1897 ) occur in pairs and are located in the anterolateral region of the general cavity, with milky white color and approximately equal sizes. They consist of a secretory portion and an excretion duct. In some glandular acini, all the cells had a basophilic appearance they were stained by hematoxylin, whereas others presented cells with different staining affinities. In this work, we describe the variations observed in these glands during the feeding cycle of ticks [after feeding (0 h) and successively at 24, 48, 72, 96, 120, and 144 h]. The cells stained by hematoxylin were shown to be more reactive to Alcian blue, thus demonstrating the presence of acid glycosaminoglycans, whereas those stained using eosin presented weak or no reaction. A strong reaction was found by the use of the periodic acid‐Schiff (PAS) technique, thereby suggesting the presence of glycogen and/or glycoconjugates containing hexose, confirmed by using salivary amylase before PAS, with partial destaining of the slides. Continuing presence of residual staining in these cells suggests the presence of glycoconjugates containing hexose. Cells with nuclei of circular outline and few granules (of different sizes) were found in type II acini, 72 h after collection. Type I acini presented wide lumina and walls composed of larger numbers of cells of cubic to cylindrical shape. The pronounced degranulation shown in this study over the course of the feeding cycle was associated with the release of substances for oviposition. Microsc. Res. Tech., 2009.

Estudo ultra-estrutural do estômago de Trichogenes longipinnis (Britski & Ortega) (Pisces, Siluriformes, Trichomicteridae)

The observations made about the stomach of Trichogenes longipinnis (Britski & Ortega, 1983) showed a rounded organ which has in its dorsal side an accessory structure - a cul de sac - that comunicates with it. The distal part of this dorsal accessory presents characteristic of an organ that exercise respiratory functions: reduction in the thickness of the mucosa and arrangement of an intrincate continuous capilar net in close contact with the superficial cells of the epithelium. In this portion there are no glands in the lamina propria. The epithelium shows a superficial squamous cels; they are very slim, and sometimes, with the capillary endothelium form a single barrier between the organ lumen and the blood. Polyhedric cells are also present in this epithelium; they are located under the squamous cells, sheltered between capillaries and basal cells.