Fine structure of the oocyst of Nematopsis mytella (apicomplexa, porosporidae),a parasite of the mussel Mitella falcata andof the oyster crassostrea rizophorae (Mollusca, Bivalvia)from the northeastern atlantic coast of Brasil

Oocystsof Nematopsis mytella, an apicomplexa gregarine parasite of the mussel Mytella falcata (fam. Mytelidae) and of the oyster Crassostrea rizophorae (fam. Ostreidae). Were collected from Itamaracá Island and Suape, two distinct zones in the estuarine region of the northeastern coast of Brazil, near the city of Recife. The oocysts were examined by light and transmission electron microscopy. No morphological and ultrastructural differences were observed between oocysts the two host species. The oocysts were engulfed by the cytoplasm of host phagocytes, with each phagocyte containing 1-19 oocysts (usually 3-5). Each oocyst was located in the center of a spherical to ellipsoidal parasitophorous vacuole (PV) 20-25 um in diameter. The oocyst (13.2 um long and 8.4 um wide) consisted of an external wall 0.6 um thich surrounded by an internal, uninucleated sporozoit. The apical region of the wall of each oocyst contained a circular micropyle 0.8 um in diameter covered by an operculum. The oocyst wall was connected to the PV membrane by a complex network of anastomosed microfibrils. The PV matrix contained 1-2 dense bodies and the periphery was occupied by numerous glycogen particles. This is the first record of a Nematopsis sp. from the northeastern coast of Brazil and only the second from Brazil as a country.

Ocorrência do Campylobacter pylori em pacientes com gastrite e úlcera péptica / Occurrence of Campylobacter pylori in patients with gastritis and peptic ulcer

Biopsias endoscópicas do antro e da borda da lesäo péptica (úlcera gástrica e úlcera duodenal)foram obtidas de 56 pacientes para estudo histológico e microbiológico, no sentido de se determinar a ocorrência do C. pylori. Trinta e nove pacientes apresentaram evidências de gastrite antral e em 37 (94,8%) deles o bacilo foi detectado, enquanto que nos 17 com histologia normal a cultura foi positiva em somente dois (p<0,01). Nos pacientes com úlcera duodenal e úlcera gástrica a positividade para o C. pylori, no fragmento da borda da lesäo, foi de 100% e 88,8%, respectivamente. Os achados sobre a microbiologia do C. pylori näo diferiram daqueles previamente descritos em estudos similares. A microscopia eletrónica o bacilo foi encontrado próximo ou aderido às superfícies celulares sem haver sinais e localizaçäo intraepitelial. Este estudo confirma a associaçäo do C. pylori com a gastrite e a úlcera gastroduodenal, descrita na literatura