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P Meinel

Publications and source records attributed to P Meinel.

8 recordsLinked to original sources
PubMed1986

[Atomic absorption spectrophotometric determination of zinc in granulocytes, lymphocytes and serum of untreated and alloxan diabetic rats].

Atomic absorptions spectrophotometric determinations of zinc in serum, granulocytes and lymphocytes after separation of blood samples of normal and alloxan diabetic rats, control persons and diabetics by the method of Böyum verify our conception that changes of metal content and structure in cells by metal chelating agents are induced primary by chemical and secondary by disturbed carbohydrate metabolism conditions. Alloxan (200 mg/kg of body weight, intraperitoneally) destroys selectively not only the B-cells of the islets of Langerhans but also the granulocytes, while the lymphocytes are not changed in respect to the zinc content and cell count. The lymphocytes of diabetics are unchanged in the zinc content, too. The earlier opinion that leucocytes belong to the slowly exchanging zinc compartments of the blood is only exact for lymphocytes, whereas the granulocytes and the serum, corresponding to an exchange pool of metal ions, may play a more important role in the transport system of the zinc.

Animals↗
PubMed1984

[Light and electron microscopic studies of the brain, heart and pancreas in mice infected with MengoM virus].

Infection of ABAF hybride mice with MengoM viruses prepared as a suspension of mouse brain tissue (0.1 ml 10 LD50) after a series of more than 90 animal passages produced a severe panencephalitis and pancreatitis 60 h after inoculation. Histological examinations of the brain, pancreas, and heart revealed damage to the central nervous system and the acinar cells of the pancreas, consisting of a degeneration of the specific cells and their organelles, with little involvement of the heart muscle cells detectable with the electron microscope. This was consistent with high virus titers in the tissues in the period immediately following infection. The acute damage of exocrine tissues was without evidence of diabetes-like changes in the islets of Langerhans.

Animals↗
PubMed1980

[Possibilities for automatic quantitative image analysis of cell organelles stained ultrahistochemically].

Metal-containing secretory granules of alpha 2-cells of the Langerhans' islets of normal and alloxandiabetic rats were stained for electron microscopy by a special method. Thereafter the electron micrographs were analysed by the Quantimet 720 image analysing computer with respect to size of the granules and their quantitative distribution in classes. The following statistical tests verified significant differences between the distributions of the granules under normal and diabetic conditions. The secretory granules from alloxandiabetic animals were diminished distinctly. The examination by image analysing computer confirmed objectively observations, we have made and published formerly.

Animals↗
PubMed1978

[Characterization of heavy metal secretory granules in the islet tissue of adult white rats by means of the light and electron microscopy, including the high voltage electron miscroscopy and the electron microanalysis (author's transl)].

The metal secretory granules of Langerhans' islets of white rats were examined after histochemical detection by sulfide silver staining method as well as by conventional electron microscopy and high voltage electron microscopy. Zinc and calcium were determined with electron probe x-ray-microanalysis. The metals are located at the inside of cytoplasmatic vacuoles, a result, we discuss in connection with the release of pancreatic hormones.

Animals↗
PubMed1977

[Investigations about ascertainment of exact morphological indices for the functionally activity of islets cells by means of electron optical characterizing and succeeded automatically image analysis of metal-containing secreting granules (author's transl)].

Biological image analysis with the "Quantimet 720" has been surrounded to date by difficulties due to the complexity of the image itself, and the difficulty of the Quantimet to discriminate between different objects on the basis of their grey levels alone (Bradbury 1975). Although the makers of image analysing computers try to diminish these difficulties by contructing new models of computers in future, we have the opinion, that it is possible to receive already today excellent results in image analysing of structures in biology and medicine under the following condition: selective staining of objects, we want to measure by simultaneous discriminating of those structures, which influence negatively the image analysing on the basis of their grey levels.

Animals↗
PubMed1977

[Computer analyse of ultrahistochemical observed metal containing secretory granules in Langerhans islets cells of normoglycemic and diabetic rat].

Metal-containing secretory granules of alpha 2-cells of the LANGERHANS' islets of normal and alloxan-diabetic rats were stained for electron microscopy by a special method. Thereafter the electron micrographs were analysed by the Quantimet 720 image analysing computer with respect to size of the granules and their quantitative distribution in classes. The following statistical tests verified significant differences between the distributions of the secretory granules under normal and diabetic conditions. The secretory granules from alloxan-diabetic animals were diminished distinctly. The examination by image analysing computer confirmed objectively observations, we have made and published formerly.

Animals↗
PubMed1976

Directed metal determination in pre- and post-natal stages of development of the islets of Langerhans by combined histochemical metal demonstration with electron probe X-ray microanalysis.

On the examples shown above it was possible to demonstrate that electron-X-ray microanalysis does not only present an important additional method for studying histochemical heavy metal reactions but can also be expected to provide, in combination with these, essential findings for the illustration of basic biological processes.

Animals↗