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J O Soares

Publications and source records attributed to J O Soares.

16 recordsLinked to original sources
PubMed1981

Photographic defocusing: a means to render recognizable line traced models of negatively stained biological specimens.

A simple method of obtaining analogue images from traced models of biological specimens is presented. It consists of the photographic defocusing of traced models and it is illustrated with negatively stained cylindrical forms of the ASFV; the black lines of the trace in the model correspond to the negative stain surrounding the viral morphological subunits as seen in the electron micrograph. The photographic defocusing is the means by which the traced model is filtered and is used to introduce grey levels on an otherwise black and white image. The right amount of defocusing is attained when the width of the trace of the model equals the width of the rim of the negative stain appearing between the morphological subunits in the electron micrograph.

African Swine Fever Virus↗
PubMed1979

Micro-buffy coats of whole blood: a method for the electron microscopic study of mononuclear cells.

A method for the electron microscopic study of human peripheral lymphocytes by which very small buffy coats are obtained through centrifugation of heparinized whole blood in glass or plastic microhematocrit tubes is presented. This method is time saving and efficient, yielding well preserved material and a comparatively large number of mononuclear cells (mainly lymphocytes) in each thin section.

Cell Separation↗
PubMed1978

Autophagy in mouse hepatocytes induced by lysine acetylsalicylate.

I.v. administration of lysine acetylsalicylate inces autophagy in mouse liver cells. Single and multiple membrane-bounded vacuoles were found. The latter seems to be an unusual morphological form of the sequestration process. These findings could express a transitory sublethal liver cell injury induced by the drug.

Animals↗
PubMedDate not supplied

Evidence for the generation of specific T suppressor lymphocytes by Streptococcus intermedius.

Crude extracellular products of the Streptococcus intermedius "CEP-Si" were able to strongly decrease the in vitro proliferation of stimulated human peripheral blood mononuclear cells (HPBMC) when evaluated by (3H)-thymidine and (3H)-leucine uptake. On the other hand, CEP-Si only slightly decreased this proliferation when HPBMC were either not stimulated or cultured in poor conditions or immature cells, i.e. thymocytes were used as target instead. Also in vivo CEP-Si was ineffective when target cells were not highly reactive. Both in vivo and in vitro, the effect of CEP-Si was proportional to the time of contact with the target cells. The dynamics of the effects of CEP-Si suggest the generation of "something" ("suppressor cells") which cause an abrupt drop in the values of (3H)-thymidine uptake rather than a progressive decrease of the values, which could indicate a loss effector or helper cells. On the other hand, CEP-Si suppressed the in vitro primary immunization of human HPBMC against SRBC and, furthermore, human HPBMC incubated with CEP-Si were able to suppress the primary immune response against SRBC of, CEP-Si untreated, HPBMC. In some instances of insufficient time of contact of CEP-Si with the target cells, an enhancement of the immune response was observed both in vivo and in vitro. Moreover, the histological pattern of the spleens of C57 BL/6 mice injected with semipurified products of CEP-Si were consistent with an adjuvant-like effect. Finally, the target HPBMC for the semipurified products of CEP-Si acquired the ultrastructural and antigenic characteristics of suppressor T lymphocytes.

Animals↗