photooxidation as an important process, which significantly affects the service life of the polypropylene products, has been the subject of much theoretical and experimental study. pigments used often change the light stabilities of polypropylene. out-door applications of pigmented polypr-opylene are now increasingly developed in products such as artificial grass. the aim of this work is to exa...

This paper describes the development of a mutant strain associated with periodic albinism (ap) in the clawed toad Xenopus laevis. The most outstanding feature of this mutation is the instability of the albino state. In the course of the development there is a succession of three periods of pigment expression: (1) complete absence of melanin pigment, (2) appearance of melanin in the pigmented ep...

PURPOSE The expression of the Sigma 1 receptor and the ability of receptor antagonists to inhibit growth and induce pigment formation were investigated in human lens epithelial cells. METHODS Capsular bags were formed for experimental purposes by performing sham cataract operations on donor lenses. The resultant bags were cultured in Eagle's minimum essential medium (EMEM) alone or supplement...

Teleost chromatophores have proven valuable in the study of the cytomatrix and its involvement in intracellular transport. These cells, which move their pigment rapidly, can be isolated from the scales of fish and maintained in culture for several days. Their transport activity can be followed with the light microscope and recorded by cinematography . Individual pigment granules can be seen mov...

The rosy gene in Drosophila melanogaster codes for the enzyme xanthine dehydrogenase (XDH). Mutants that have no enzyme activity are characterized by a brownish eye color phenotype reflecting a deficiency in the red eye pigment. Xanthine dehydrogenase is not synthesized in the eye, but rather is transported there. The present report describes the ultrastructural localization of XDH in the Droso...

The intracellular localization of acid phosphatase in guinea pig testicular interstitial cells was investigated by incubating nonfrozen thick sections of glutaraldehyde-perfused testis in a modified Gomori medium and preparing the tissue for electron microscopy. Lipofuscin pigment granules in these cells contain dense pigment, granular matrix, and often a lipid droplet. Reaction product is seen...