Human monocyte-derived macrophages ingest diamide-treated red blood cells (RBC), anti-D immunoglobulin (Ig)G-opsonized RBC, or Plasmodium falciparum ring-stage parasitized RBC (RPRBC), degrade ingested hemoglobin rapidly, and can repeat the phagocytic cycle. Monocytes fed with trophozoite-parasitized RBC (TPRBC), which contain malarial pigment, or fed with isolated pigment are virtually unable ...

In the eyes of teleosts and amphibians, melanin pigment granules of the retinal pigment epithelium (RPE) migrate in response to changes in light conditions. In the light, pigment granules disperse into the cells' long apical projections, thereby shielding the rod photoreceptor outer segments and reducing their extent of bleach. In darkness, pigment granules aggregate towards the base of the RPE...

1. Two important methods for the study of malarial pigment are described. (a) A method for obtaining a solution of malarial pigment from fixed tissues without the removal of a trace of hemoglobin from the red blood corpuscles. (b) A method for obtaining an iron reaction in malarial pigment. 2. By comparing the bleach reactions and solubility of melanins and malarial pigment, the dissimilarity o...

Closure of previously patent laser iridotomies has been described as occurring early or late after the procedure. Early closure, occurring from minutes to hours after completion of the iridotomy, results from landsliding of iris pigment epithelium from above the site of the iridotomy or from large pigment particles floating in the posterior chamber, lodging in the iridotomy site, and occluding ...

Ripping of detached pigment epithelium appears to be a common sight-threatening complication of pigment epithelial detachments and occurs at the junction of the detachment and flat pigment epithelium. The characteristics of the detachment prior to the rip suggest that the tear occurs in pigment epithelium which is detached without its basement membrane. The tear is followed by retraction of the...

To directly test the hypothesis that only two pigment genes are expressed from the X-chromosome array, we examined expressed M and L pigment gene sequences from > 100 male eye donors. In this sample, there were eight men who expressed high levels of more than one L pigment gene in addition to M pigment genes. The fact that these eyes expressed both L and M pigment genes at significant levels su...