| 1. |
- Elofsson, Rolf, et al.
(författare)
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Catcholaminergic salivary glands in Gammarus pulex (Crustacea, Amphipoda): An electron microscopic and microspectrofluorometric study
- 1978
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Ingår i: Journal of Ultrastructure Research. - 0022-5320. ; 64, s. 14-22
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Tidskriftsartikel (refereegranskat)abstract
- The type of gland (salivary gland) described here for the amphipod Gammarus pulex belongs to the tegumental glands, which have different structural characteristics. The present type, called rosette gland, is common in some crustaceans and is located in the ventral half of the head. The functional unit is a lobule of gland cells with a central-draining duct. Ducts from groups of lobules conjoin and terminate on the body surface at different points around and in the mouth and mouth parts. With the fluorescence histochemical method of Falck and Hillarp, specific green fluorescence was discerned centrally in the lobules and was confined to the gland cells. The spectral characteristics of the fluorescence, as revealed by microspectrofluorometric analysis, indicated either a mixture of dopamine and a presumed new catechol compound or the presence of two tautomeric forms either of dopamine or of a new catechol compound. Evidence of new catechol compounds with similar spectral characteristics has previously been found in the sensory cells of some invertebrates. The fluorescence distribution within the lobule coincides with the presence, ultrastructurally, of large dense vesicles in the gland cells. These dense vesicles occur in the predominant cell type, also characterized by a smooth endoplasmic reticulum. The other cell type in the lobules differs ultrastructurally by possessing a rough endoplasmic reticulum and a different vesicle type. No innervation of the salivary gland was perceived.
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| 2. |
- Elofsson, Rolf, et al.
(författare)
-
Correlation of ultrastructure and chemical composition of crustacean chromatophore pigment
- 1973
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Ingår i: Journal of Ultrastructure Research. - 0022-5320. ; 44, s. 421-429
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Tidskriftsartikel (refereegranskat)abstract
- Chromatophores, with chemically identified pigment, from the body and eyes of crustaceans were investigated ultrastructurally. Red carotenoid-, black ommochrome-, and white pteridine-containing chromatophores were found to have pigment granules of different morphological appearance.
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| 3. |
- Elofsson, Rolf, et al.
(författare)
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The ciliated human keratinocyte
- 1983
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Ingår i: Journal of Ultrastructure Research. - 0022-5320. ; 87, s. 212-220
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Tidskriftsartikel (refereegranskat)abstract
- Human keratinocytes were investigated for the presence of single cilia. Almost all basal keratinocytes were found to carry a single cilium in normal, occluded, and psoriatic skin. The ciliary structure was progressively reduced in keratinocytes approaching the surface. No remnants of the ciliary apparatus were found in the granular layer. In one case of nickel-allergic dermatitis (patch test), the keratinocytes had lost their cilia; the significance of this surprising finding remains to be elucidated.
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| 4. |
- Elofsson, Rolf, et al.
(författare)
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The ultrastructure of the chromatophores of Crangon and Pandalus (Crustacea)
- 1971
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Ingår i: Journal of Ultrastructure Research. - 0022-5320. ; 36, s. 263-270
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Tidskriftsartikel (refereegranskat)abstract
- The ultrastructure of the chromatophores of two decapod crustaceans, Crangon crangon and Pandalus borealis, is investigated. The pigment appears macroscopically as small units, so-called chromatosomes. These contain separate chromatophores of different colors, and each color is composed of several chromatophores. Each chromatophore contains pigment granules, tubuli (ca. 210 Å), a network of cisternae of the endoplasmic reticulum, and mitochondria. A close contact exists between the cisternae and the pigment granules. The tubuli are arranged in thick bundles in the chromatophore extensions. The pigment granules of chromatophores of different colors are found to be structurally different. This phenomenon, as well as the structure of the whole chromatophore, is related to the vertebrate chromatophores.
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| 5. |
- Thyberg, Johan, et al.
(författare)
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Electron microscopic demonstration of proteoglycans in guinea pig epiphyseal cartilage
- 1973
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Ingår i: Journal of Ultrastructure Research. - 0022-5320. ; 45:5-6, s. 407-427
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Tidskriftsartikel (refereegranskat)abstract
- Guinea pig epiphyseal cartilage was studied ultrastructurally after staining with ruthenium red or Alcian Blue. Extracellularly, the matrix granules were positively stained with both dyes, whereas no apparent staining of the collagen fibrils occurred. Intracellularly, a positive ruthenium red staining of the Golgi vacuole granules was observed. No Alcian Blue staining of the content of the vacuoles was detected. The fresh, untreated cartilage contained about 1.3% hexosamine on a dry weight basis. About three-fourths thereof represented chondroitin sulfate, the remaining part keratan sulfate and glycoproteins. After digestion of thin cartilage slices with hyaluronidase or chondroitinase ABC the chondroitin sulfate content was less than 50% of that in the buffer-incubated controls. Concomitantly, the matrix granules were reduced in size and number or completely absent. Papain digestion removed more than 90% of the chondroitin sulfate and all matrix granules. From these findings it was concluded that the matrix granules contain proteoglycans. Moreover, it seemed reasonable to assume that the Golgi vacuole granules, at least in part, represent intracellular proteoglycans. Signs of secretion of these granules by exocytosis were occasionally observed.
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