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Biomedical subjects

J S Read

Publications and source records attributed to J S Read.

6 recordsLinked to original sources
PubMed1992

Lysis of erythrocytes by Trichomonas vaginalis.

The in vitro hemolytic activity of 4 isolates of Trichomonas vaginalis was investigated. Repetitive hemolysis assays of any one isolate showed cyclical fluctuations in hemolytic activity, varying over 24 hr of continuous culture. Maximal hemolytic activity was detected using trichomonads in the lag phase of the growth cycle. Investigations showed that hemolysis was a contact-dependent phenomenon and microscopic investigation of samples showed a significant correlation between hemolysis and attachment of erythrocytes to the trichomonad surface. Quantitative data from cytoadherence assays using [51Cr]-labeled erythrocytes were consistent with these observations. It is suggested that hemolytic activity is dependent upon adherence of red blood cells to the surface of T. vaginalis.

Animals↗
PubMed1988

Evaluation of choroidal neovascular membranes by Octopus perimetry.

A Sargon user-defined Octopus program was devised to quantitate central visual field changes following laser photocoagulation for choroidal neovascular membranes. The program was found to be reliable in testing the nine patients studied. All patients had areas of improved and areas of reduced sensitivity. The areas of reduced sensitivity were larger than the areas of improved sensitivity (P less than 0.05), with a net negative change in sensitivity found in all cases. However, the improved areas tended to be closer to fixation than the worsened areas. Quantitative static perimetry can be applied to the study of choroidal neovascular membranes. It is an important visual parameter that should be evaluated in future studies of these membranes, especially with regard to wavelength efficacy in photocoagulation therapy.

Choroid↗
PubMed1986

Foveal cone pigment density difference in the aging human eye.

Using fundus reflectometry, we have measured a decrease in the density difference of the foveal cone visual pigments with age in human subjects. This decrease is consistent with a loss of visual pigment in the retina with age. Fundus reflectance and normalized density difference spectra data are presented for these subjects. A decrease in cone pigment with age would be consistent with both anatomic studies, which indicate a loss and displacement of photoreceptors with age, and psychophysical studies, which demonstrate loss of photoreceptor function with age.

Adult↗