scholarly journals Chromatophoromas in Two Species of Hawaiian Butterflyfish, Chaetodon multicinctus and C. miliaris

1988 ◽  
Vol 25 (6) ◽  
pp. 422-431 ◽  
Author(s):  
M. S. Okihiro
Keyword(s):  
Pigment Cell ◽  
The State ◽  
Melanin Pigment ◽  
Chaetodon Multicinctus ◽  
Olive Green

Chromatophoromas (cutaneous pigment cell tumors) were seen in two species of butterflyfish, Chaetodon multicinctus and Chaetodon miliaris, over an 11-year period (1976–1987) in waters off the islands of Maui, Lanai, and Molokini in the state of Hawaii. The chromatophore tumors found in the brown-barred butterflyfish, C multicinctus, were predominantly iridophoromas (characterized by the presence of birefringent olive-green crystalline pigment), while the tumors in the lemon butterflyfish, C. miliaris, were primarily melanophoromas (characterized by the presence of melanin pigment). Mixed chromatophoromas, composed of iridophores, melanophores, and undifferentiated chromatophores, were found in both species. The prevalence of chromatophoromas in C. multicinctus off the island of Maui varied from a low of 22–25% in 1976 to a high of 50% in 1987. The estimated prevalence of chromatophoromas in C. miliaris was 2.5% off the island of Molokini in 1976, and 5.0% off Lanai in 1987. The cause or causes of chromatophoromas in these two species of butterflyfish has not been determined.

Basic Mechanisms in the Differentiation of Pigment Cells

Development ◽  
1953 ◽  
Vol 1 (3) ◽  
pp. 297-299
Author(s):  
B. H. Willier
Keyword(s):  
Chick Embryo ◽  
Experimental Analysis ◽  
Cellular Differentiation ◽  
Pigment Cell ◽  
Melanin Pigment ◽  
Pigment Cells ◽  
Colour Pattern ◽  
Pigment Granules ◽  
Specific Behaviour ◽  
The Moment

Some of the basic mechanisms of cellular differentiation have been elucidated by an experimental analysis of the underlying factors and conditions which control the processes of differentiation of the pigment cell in the chick embryo. The pigment cell, owing to its singular capacity to synthesize melanin pigment granules, is an ideal cell for locating its site of origin and tracing its subsequent pathways to the skin and derivatives, the feather papillae. It has the further advantage that its specific behaviour is recorded as colour or colour pattern in the mature feather. In other words, by using the pigment-forming cell as a ‘marker’ many of its properties in time and space may be ascertained from the moment that it is first set aside as a specialized strain of cell until it reaches its ultimate position and visible expression in the growing feather papilla.

The development of animals homozygous for a mutation causing periodic albinism (ap) in Xenopus laevis

Development ◽  
1975 ◽  
Vol 34 (1) ◽  
pp. 253-264
Author(s):  
Olga A. Hoperskaya
Keyword(s):  
Cell Differentiation ◽  
Xenopus Laevis ◽  
Mutant Strain ◽  
Pigment Cell ◽  
Melanin Pigment ◽  
Recessive Trait ◽  
Pigment Granules ◽  
Outstanding Feature ◽  
Pigmented Epithelium

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 epithelium of the eyes and in small quantities in skin melanophores, (3) disappearance of most pigment granules. Repeated spawnings show that the mutant syndrome is inherited as a recessive trait. Possible ways of analysing pigment cell differentiation with the use of the mutation described are discussed.

Arylsulphatase and the melanin pigment cell cycle

1970 ◽  
Vol 1 (3) ◽  
pp. 257-262 ◽  
Author(s):  
Lee Roy Morgan ◽  
Nelville J. Reehlmann ◽  
Betty Maddux ◽  
Monroe S. Samuels ◽  
Edward T. Krementz
Keyword(s):  
Cell Cycle ◽  
Pigment Cell ◽  
Melanin Pigment

Practical Picture Processing

1974 ◽  
Vol 32 ◽  
pp. 338-339
Author(s):  
T. A. Welton
Keyword(s):  
Radiation Damage ◽  
Coherence Length ◽  
Spatial Information ◽  
State Of The Art ◽  
Coherent Radiation ◽  
The State ◽  
Energy Spread ◽  
Electron Micrograph ◽  
Picture Processing ◽  
Molecular Skeleton

Various authors have emphasized the spatial information resident in an electron micrograph taken with adequately coherent radiation. In view of the completion of at least one such instrument, this opportunity is taken to summarize the state of the art of processing such micrographs. We use the usual symbols for the aberration coefficients, and supplement these with £ and 6 for the transverse coherence length and the fractional energy spread respectively. He also assume a weak, biologically interesting sample, with principal interest lying in the molecular skeleton remaining after obvious hydrogen loss and other radiation damage has occurred.

Pragmatic versus Morphological/Syntactic Criteria for Language Referrals

1980 ◽  
Vol 11 (2) ◽  
pp. 85-94 ◽  
Author(s):  
Jack Damico ◽  
John W. Oller
Keyword(s):  
Grade Level ◽  
The State ◽  
Verb Agreement ◽  
Remedial Programs ◽  
Service Training ◽  
Traditional Approaches ◽  
Communicative Effectiveness

Two methods of identifying language disordered children are examined. Traditional approaches require attention to relatively superficial morphological and surface syntactic criteria, such as, noun-verb agreement, tense marking, pluralization. More recently, however, language testers and others have turned to pragmatic criteria focussing on deeper aspects of meaning and communicative effectiveness, such as, general fluency, topic maintenance, specificity of referring terms. In this study, 54 regular K-5 teachers in two Albuquerque schools serving 1212 children were assigned on a roughly matched basis to one of two groups. Group S received in-service training using traditional surface criteria for referrals, while Group P received similar in-service training with pragmatic criteria. All referrals from both groups were reevaluated by a panel of judges following the state determined procedures for assignment to remedial programs. Teachers who were taught to use pragmatic criteria in identifying language disordered children identified significantly more children and were more often correct in their identification than teachers taught to use syntactic criteria. Both groups identified significantly fewer children as the grade level increased.

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