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R Odselius

Publications and source records attributed to R Odselius.

26 records · Page 2Linked to original sources
PubMed1985

Energy dispersive X-ray microanalysis of zinc and calcium in organelles of insulin-producing cells of the mouse, rat, and a fish.

By means of energy dispersive X-ray microanalysis in the scanning-transmission electron microscope, spectra were obtained from quick-frozen, cryo-ultramicrotome cut, freeze-dried sections of insulin cells from a fish and a mouse. It was shown that both zinc and calcium are present in significant quantities in native islet-cell beta-granules. In the beta-granules of the rat RINm5F insuloma cells calcium, but not zinc, seemed to accumulate; the zinc contents in the secretion granules of these neoplastic beta-cells were probably below the detection limit.

Animals↗
PubMed1984

Vapor fixation for immunocytochemistry and X-ray microanalysis on cryoultramicrotome sections.

Several organic and inorganic vapor fixatives have been tested for their ability to stabilize the ultrastructure of freeze-dried thin cryosections. The vapors from osmium tetroxide and dry formaldehyde gave a good preservation of the ultrastructure. Fixation in formaldehyde vapor preserved the immunoreactivity of alpha-amylase in exocrine pancreas, as was demonstrated with an indirect labeling technique using anti-alpha-amylase and protein A-gold. A major advantage of the use of vapor fixation is that cryosections from a specimen of fresh-frozen tissue can be used for immunocytochemistry as well as for X-ray microanalysis, as was demonstrated for the exocrine pancreas. This opens the possibility of localizing atomic species (X-ray microanalysis) and molecular species (immunocytochemistry) at the subcellular level on thin cryosections from the same tissue block.

Animals↗
PubMed1984

Electron microprobe analysis and histochemical examination of the calcium distribution in human bone trabeculae: a methodological study using biopsy specimens from post-traumatic osteopenia.

Energy dispersive X-ray microanalysis (EDX) (or electron microprobe analysis) of the relative intensity for calcium in different bone trabeculae from the tibia epiphysis, and in different parts of one and the same trabecula, was performed on 3 patients who had earlier had a fracture of the ipsilateral tibia-diaphysis. The variation in intensity was compared with the histochemical patterns obtained with both the Goldner and the von Kóssa staining techniques for detecting calcium in tissues. Previously reported calcium distribution features, found to be typical for posttraumatic osteopenia, such as striated mineralization patterns in individual trabeculae and large differences in mineralization level between different trabeculae, could be verified both by means of the two histochemical procedures and from the electron microprobe analysis. A pronounced difference was observed, however, between the two histochemical staining techniques as regards their sensitivity to detect calcium. The two methods have different turnover points, from negative to positive along a gradient change of calcium concentrations. To judge from the values obtained from the EDX measurements, the sensitivity of the Goldner technique should be more than ten times higher than that of von Kóssa. The EDX measurements gave more detailed information than either of the two histochemical techniques: great variations in the intensity of the calcium peak were found in trabeculae stained as unmineralized as well as mineralized.

Adult↗
PubMed1983

The compound eye of Leptodora kindtii (Cladocera). An adaptation to planktonic life.

Each of the approximately 500 ommatidia in the compound eye of the cladoceran crustacean Leptodora kindtii has a crystalline cone consisting of five cells. Five retinula cells are also present, one of which contributes to the distal 1-2 micrometer of the rhabdom only; the other four retinula cells from a continuous rhabdom. Throughout the rhabdom its cross section displays two separate halves with the axis of the microvilli in one half perpendicular to that in the other (orthogonal pattern). Interferometric analysis of the refractive index of the crystalline cone revealed an inhomogeneous system with one distal and one proximal gradient. The gradient system was found to exclude rays entering from adjacent facets, thus maintaining the optical isolation. Consequently, these optics replace distal screening pigment, which is absent in the eye. The long and unscreened crystalline cones give rise to an almost transparent eye in conformity with the overall transparency of this plank-tonic animal. The morphological characteristics of the eye of this species deviate from other cladoceran eyes, but the optical design closely resembles that of some pelagic marine amphipod crustaceans.

Adaptation, Physiological↗
PubMed1981

The basement membrane of the insect and crustacean compound eye: definition, fine structure, and comparative morphology.

The basement membrane of the compound eye of four insect species and three crustacean species was investigated employing electron microscopy. The basement membrane consists of an extracellular (basal lamina) and a cellular portion, the latter being composed of the flattened terminal extensions of cone cells and accessory pigment cells in insects and distal pigment cells in crustaceans. Other cells can also contribute to the basement membrane. It is thus a complex structure in all well--developed compound eyes. The cellular contributions vary in different species and were found to correlate to specific taxonomic units.

Animals↗
PubMed1978

Neuronal connectivity patterns in the compound eyes of Artemia salina and Daphnia magna (Crustacea: Branchiopoda).

The neuronal types and patterns in the visual system of the species Artemia salina and Daphina magna have been studied with the Golgi method and electron microscopy. The lamina contains five classes of neurons: photoreceptor axons, monopolar, centrifugal, tangential and amacrine neurons. The terminals of the receptor axons are distributed in two (A. salina) or three (D. magna) layers. The dilated terminals have an extensive and wide array of fine branches. One axon from each ommatidium bypasses the lamina and terminates in the medula in A. salina. A. salina has four types of monopolar neurons, two of which are stratified, whereas in D. magna only two types are found, one of which is bistratified. Tangential T-neurons connect the lamina with the protocerebrum. D. magna has in addition one tangential T-neuron connecting both the lamina and the medulla with the protocerebrum. In both species monopolar-type centrifugal neurons connect the medulla and the lamina, whereas that of A. salina has a wide laminar distribution. Both species also have amacrine cells in the lamina. The medulla contains, besides those shared with the lamina, transmedullary neurons (two types in A. salina), amacrine cells and neurons originating in the protocerebrum. "Cartridge"-type synaptic compartments are lacking in the investigated species, although a periodic arrangement is discernible in the distal portion of the lamina of A. salina. The receptors from three types of specialized contacts in Artemia, one of which involves a dyad. D. magna has only one-to-one synapses. Neurosecretory fibres are absent in A. salina.

Animals↗
PubMedDate not supplied

A simple method for processing cytologic samples obtained from body cavity fluids and by fine needle aspiration biopsy for ultrastructural studies.

A simple method for processing routine cytologic samples for electron microscopy is described. The method has been successfully applied to body cavity fluids and fine needle aspiration biopsies. The technique neither requires additional time and personnel nor interferes with the normal activity of the laboratory.

Biopsy, Needle↗