Alkaline phosphatase at the cell wall of the yeast phase of Paracoccidioides brasiliensis.

The activity of alkaline phosphatase demonstrated by histochemical techniques was shown at the cell wall of the yeast form of Paracoccidioides brasiliensis at 3, 6, and 9 days of culture. The results showed a very active deposition at the cell wall as early as 9 days of culture of the fungus which made us think an inactive salt precipitate was also present.

Strianema venezuelensis gen. et sp. n. (Filarioidea: Onchocercidae) from Venezuelan armadillos (Dasypus spp.).

A new filaria, Strianema venezuelensis gen. et sp. n., is described from armadillos in Venezuela. The adults inhabit the subcutaneous tissues and the microfilariae are found in the skin and occasionally the blood. The adults, which are of small size (males 9.6 to 13.8 mm in length by 57 to 63 microns in diameter, females 18.3 to 26.3 mm in length by 95 to 120 microns in diameter), have a distinctly striated cuticle. This filaria resembles most closely the genus Cercopithifilaria, from which it can be distinguished by the absence of a buccal capsule or pre-esophageal ring, and 11 to 13 pair of caudal papillae, three or four pair of which are separated as a group anterior to the cloaca. The species, S. venezuelensis, can be distinguished from the three other species of filariae described from armadillos by the undivided esophagus, number and distribution of caudal papillae in the male, size and shape of the spicules, and the distinctive microfilaria. The microfilaria, which averages 280 microns in length, has a unique, slender, almost filamentous tail.

Hydrolytic activity of an onchocercoma.

The onchocercoma or nodule produced by the nematode Onchocerca volvulus (Filarioidea) in the skin of patients suffering from onchocerciasis has not been examined by histochemical techniques. In this work we have used histochemical techniques to evaluate 5 hydrolytic enzymes, namely phosphatases, esterases and beta-glucuronidase. The results show increased enzymatic activity at the sites of major metabolic activity and within reactive cells including macrophages (mc) and giant cells (gc) of the onchocercoma.

Plaquetas humanas actividad de fosfatasa ácida en plaquetas de donantes del Banco Municipal de Sangre del Distrito Federal / Human platelets activity of acid phosphatase in giver platelets of the Bank Municipal of the Federal District

Se demuestra la actividad hidrolítica de las plaquetas humanas utilizando la presencia de Fosfatasa Acida en el cromómero o sea en los gránulos densos A-G de plaquetas obtenidas del Banco Municipal de Sangre del Distrito Federal. Para ello se utiliza el metódo de Gomori con las modificaciones de Holt & Hicks y de Etherton & Botham para microcopía electrónica. Se demuestra la presencia de Fosfatasa Acida en el cromómero de las plaquetas lo que indica que estos gránulos poseen la capacidad hidrolítica necesaria para hidrolizar los ésteres de fosfatos liberados durante la reacción histoquímica

Adenosine triphosphatase in yeast phase Paracoccidioides brasiliensis.

We have previously detected various enzymatic activities in P. brasiliensis. In the present study we have examined Adenosine Triphosphatase (ATPase) activity in yeast phase cultures of P. brasiliensis of increasing age. We employed Wachstein and Meisel's method and electron microscopy and found specific electron-dense deposits indicating ATPase activity to be present in the cytoplasm around vacuoles. Their distribution varied according to age. Deposits decreased or became absent in old cultures. We assume that in P. brasiliensis, ATPase is involved (as in other systems) with transport of Na+ and K+.

[Preservation of blood platelets concentrates at different temperatures]. / Conservación de concentrados plaquetarios a diferentes temperaturas.

The temperature storage of the platelet concentrates (PC) it's of utmost importance in order to preserve the viability and the hemostatic function of the platelets. In the following study we made a comparative evaluation of the PC stored at three different temperatures: Volume, platelet count, pH, pCO2, pO2, in vitro aggregation, bacterial growth, ultrastructure changes and survival, to test its quality and usefulness. The results provide evidence that the PC kept at 27 degrees C showed marked differences compared with the PC stored at 22 degrees C. For example, the platelets showed the strongest morphological changes, less survival and probably a higher metabolic activity than those kept at 22 degrees C. Although the in vitro function was altered, it was recovered after 90 minutes of incubation with fresh frozen plasma. According with these results we can conclude that the in vivo hemostatic activity of these PC is as efficient as those stored at 4 and 22 degrees C, but due to the decreased of the in vivo platelet survival, we support that the 22 degrees C remain as the best temperature for the PC storage.

Conservacion de concentrados plaquetarios a diferentes temperaturas / Preservation of blood platelets concentrates at different temperatures

La temperatura de conservación de los concentrados plaquetarios (CP) es muy importante para preservar la función hemostática de las plaquetas, en el presente trabajo se hizo una evaluación comparativa entre CP conservados a 4,22 y 27-C(-27-C- temperatura ambiente en algunos de nuestros laboratorios), analizando los siguientes parámetros: volumen, contaje plaquetario, pH, pCO2, pO2, desarrollo bacteriano, cambios morfológicos ultraestructurales, agregación plaquetaria in vitro y sobrevida, con el fin de evaluar la calidad de las plaquetas y su posible utilización. De acuerdo a los datos obtenidos, los CP conservados a 27-C en comparación a los de 22-C (temperatura óptima de conservación) muestran diferencias importantes. Los cambios morfológicos a 27-C son más acentuados, la sobrevida es más corta y la actividad metabólica pareciera ser mayor. El funcinalismo in vitro está alterado pero se recupera después de un período de incubación de 90 minutos con plasma fresco, lo que hace suponer que homostáticamente son tan activas como las de 22-C y 4-C, sin embargo, debido a su corta sobrevida in vivo, la conservación a 22-C continúa siendo la ideal

La citoestructura de Mycobacterium leprae en pellet y vacuolas fagocíticas del nódulo hanseniano activo / Structure of Mycobacterium leprae in pellet and phagocitic vacuoles of active hansen node

Se hace estudio ultraestructural del bacilo de Hansen a 20.000 x en pellet y en vacuola del nódulo hanseniano activo. Se observa su pared celular, membrana plasmática mesosoma y nucleoide. En su citoestructura no se diferencia de otras bacterias ya sean éstas Gram positivas o Gram negativas. Solo las diferencia su ácido resistencia la cual le da sus características tintoriales especiales

Acanthocheilonema sabanicolae n. sp. (Filarioidea: Onchocercidae) from the savanna armadillo (Dasypus sabanicola) in Venezuela, with comments on the genus Acanthocheilonema.

A new species of Acanthocheilonema, Acanthocheilonema sabanicolae n. sp., is described from the subcutaneous tissues of the savanna armadillo (Dasypus sabanicola) in Venezuela. The adults (females 25-30.6 mm long by 61-78 micron wide; males 10.9-15.3 mm long by 42-44 micron wide) and the microfilariae (112-131 micron long by 3-5 micron wide) are the smallest within the genus. The microfilaria, a skin dweller, assumes a characteristic C-shaped curve, when fixed in 2% formalin, which serves to distinguish A. sabanicolae from others in the genus. Moreover, the spicules are notably smaller than any others in the Acanthocheilonema. Acanthocheilonema sabanicolae is the first species in this genus to be described from edentates, and, along with A. reconditum of dogs and A. pricei of opossums, is the third species of Acanthocheilonema to be reported from South America. Morphological features, vectors, and vertebrate hosts of the genus Acanthocheilonema are reviewed.

[Dipetalonema (Alafilaria) hydrochoerus Yates (1983)]. / La Dipetalonema (Alafilaria) hydrochoerus Yates (1983).

Four filariae are known to parasitize the capybara "Hydrochoerus hydrochaeris" namely the "Cruorifilaria tuberocauda", Eberhard, Morales & Orihel, 1976; the "Dipetalonema (Alafilaria) hydrochoerus", Yates & Jorgenson, 1983, and "Mansonella longicapita" and "Mansonella rotundicapita [corrected]", Eberhard, Campo-Aasen & Orihel, 1983. In this study we describe briefly the adult parasites and, the microfilaria of the species "Dipetalonema (Alafilaria) hydrochoerus" which were isolated from skin nips and we have found that the capybara "Hydrochoerus hydrochaeris" is parasitized in a proportion of 80% in the 16 animals studied.

Histochemical localization of succinate dehydrogenase in the mitochondria of Paracoccidioides brasiliensis.

The succinate dehydrogenase activity of Paracoccidioides brasiliensis was investigated histochemically by electron microscopy. The reaction product of this enzyme was demonstrated in some membranous structures of organelles interpreted as mitochondria. This enzyme shows very active oxido-reduction in Paracoccidioides brasiliensis mitochondria during, 3, 6, and and 9 days of culture.

Mansonella (E.) rotundicapita sp.n. and Mansonella (E.) longicapita sp.n. (Filarioidea : Onchocercidae) from Venezuelan capybaras, Hydrochoerus hydrochaeris.

Mansonella (E.) longicapita sp. n. and Mansonella (E.) rotundicapita sp. n., two filarial nematodes from the dermis of Venezuelan capybaras, are described. The two species can be distinguished on the size of the spicules (M. longicapita 327 and 139 micron, ratio of 2.3 : 1 ; M. rotundicapita 405 and 120 micron, ratio of 3.4 : 1), the degree of lateral elongation of the cephalic shield and in the size and configuration of the microfilaria. The microfilaria of M. rotundicapita is large (280 micron long), and in specimens fixed in 2% formalin, the posterior end of the body is bent in a shepherd's crook, while the microfilaria of M. longicapita is short (195 micron long) and when similarly fixed, assumes a gently curved attitude. Within the subgenus M. (Esslingeria), the species M. longicapita and M. rotundicapita are intermediate in size. Morphologically they resemble M. streptocerca and M. rodhaini most closely, but can be distinguished on size, spicule morphology, and microfilarial morphology.

Carboxylic activity of giant cells of human granuloma produced by Paracoccidioides brasiliensis.

The carboxilic activity of giant cells of human granuloma produced by P. brasiliensis was studied. The enzymatic activity was revealed by reddish-brown, purple red, and indigo-blue cytoplasmic precipitate, using the substrates alpha-naphthyl-acetate, naphthol-AS acetate and 5-bromo-4-chloro-indoxyl acetate respectively. The giant cells were intensely positive in all cases studied. We believe this esterasic activity is related to the lytic, lisosomic activity of the macrophages and giant cells in response to the activity by the P. brasiliensis in tissue.

The histochemistry of armadillo skin.

The histochemistry of armadillo skin has been studied. The dendritic cells are extremely large, very sharply outlined by methods for alkaline phosphatase and alpha-naphthyl-acetate esterase, and they are dopa-negative. The mastocytes, however, are dopa-oxidase-positive, probably due to peroxidase rather than tyrosinase activity. The giant cells of the granulomas normally seen in the dermis of the armadillo are strongly beta-glucuronidase-positive. These giant cells are evidently foreign body cells reacting to the crystals always present in the dermis of the armadillo. The centre of these crystals, which are cholesterol and fat-negative, is alkaline phosphatase-positive. Further study of the mastocytes and dendritic cells is necessary to elucidate their nature.