This is the first report of an amelanotic melanoma arising in the unpigmented choroid of a tyrosinase-positive oculocutaneous albino (TPOCA). Melanosomes within the tumour showed a maturation arrest in the unpigmented type II (premelanosome) phase. Other neural crest derived melanocytes in iris and choroid showed similar limited melanogenesis. The neuroectodermally derived melanocytes of the ir...

A transplantable melanoma of golden Syrian hamsters was grown in tissue culture and four stable cell lines were obtained by cloning techniques. Cells of these lines differ from each other in growth patterns as well as in production of radial-type virus and synthesis and degradation of melanosomes. Cells of one line (KF) produced large amounts of virus and little or no pigmented melanosomes, whi...

A transplantable melanoma of golden Syrian hamsters was grown in tissue culture and four stable cell lines were obtained by cloning techniques. Cells of these lines differ from each other in growth patterns as well as in production of radial-type virus and synthesis and degradation of melanosomes. Cells of one line (KF) produced large amounts of virus and little or no pigmented melanosomes, whi...

PURPOSE The aim of this study was to investigate the autofluorescence (AF) of the RPE with two-photon microscopy (TPM) and fluorescence lifetime imaging (FLIM) under normal and oxidative stress conditions. METHODS Porcine RPE-choroid explants were used for investigation. The RPE-choroid tissue was preserved in a perfusion organ culture system. Oxidative stress was induced by laser photocoagul...

PURPOSE Usher syndrome (USH) is a genetically heterogeneous disease with autosomal recessive deafness and blindness. Gene therapy is under development for use in the most common genetic variant of USH1, USH1B, which is caused by mutations in the MYO7A gene. This study was undertaken to identify an imaging method for noninvasively monitoring the RPE component of the USH1B disease. METHODS NIR-...