The pharmaceutical industry and academic medicine in collaboration.
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Attitude↗
Biomedical subjects
R Wroblewski
Publications and source records attributed to R Wroblewski.
University and pharmaceutical industry cooperation: the need to plan for the future.
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Drug Industry↗
Quantitative X-ray microanalysis of semi-thick cryosections.
Methodological aspects of quantitative X-ray microanalysis of semi-thick cryosections (2--6 micrometers) of biological soft tissue were investigated. The preparation of a low background specimen holder is described. Scanning and scanning transmission images of the sections could be obtained, allowing identification and separate analysis of nuclei and cytoplasm. Parallel observations of histochemically stained adjacent sections in the light microscope allowed correlation of the microanalytical data with tissue morphology and histochemistry. Quantitative analysis could be carried out with the help of a standard: a gelatin/glycerol matrix containing mineral salts in known quantities, frozen and sectioned in the same way as the specimen. Mass loss under the electron beam was found to be comparable in specimen and standard. Comparison of various theoretical models for quantitative analysis showed that the 'P/B-method' (determination of the background intensity under the characteristic peak) is the most suitable for semi-thick sections. Factor determining the choice of accelerating voltage were analyzed. The usefulness of this specimen type is illustrated in some biological applications (human oral mucosa, rat salivary gland).
Animals↗
Healthy and diseased epithelium of the oral and maxillary sinus mucosa studied by X-ray microanalysis.
Concentrations of Na, Mg, P, S, Cl, K, and Ca in healthy and pathologically transformed epithelial cells of oral cavity and maxillary sinus mucosa in man were measured by X-ray microanalysis. Biopsies from normal mucosa, irradiated and clinically cured squamous cell carcinoma, mucoepidermoid carcinoma from the oral cavity, and polyposis in the maxillary sinus were prepared by rapid freezing and cryosectioning. In normal mucosa, nuclei and cytoplasm of basal, intermediate and apical epithelial cells were analyzed. A slight decrease in the concentration of Na, Mg, P and Cl was found towards the apical cells. The concentration of Na in the nuclei of the different cell layers parallelled that of P. The elemental composition of the pathologically transformed cells differed markedly from that of the cells of healthy oral mucosa (higher Na and Cl). In the irradiated squamous cell carcinoma the concentrations of Mg and K were extremely low.
Aged↗
Ultrastructure and elemental composition of the stapedius muscle in guinea pig.
Muscules stapedius in guinea pig was investigated with regard to morphology and elemental composition. The muscle fibers are multinucleated, contain a high amount of ribosomes, and a centriole is often found adjacent to the cell nucleus. Intramitochondrial inclusion bodies occur adjacent to cristae mitochondriales. Both type I and type II fibres occur, the latter with all three subtypes. Elemental analysis from the myofibrillar area revealed unexpected low concentration of K and high concentrations of NA, P, and Ca.
Animals↗
The energy dispersive X-ray microanalysis technique in the study of fluids and tissues of the brain and the inner ear.
The temporal bone from the fetal and adult mouse and brain from fetal and adult rat were cryosectioned in a conventional cryostat and -30 degrees C using 16 micrometers thick sections. The elemental composition was analyzed in the fluid-filled spaces of the membranous labyrinth and ventricular cavities of the brain. After drying these spaces containing small crystal-like aggregations of material which morphologically differed depending on their elemental composition. This changed during embryonic maturation. The qualitative X-ray analytical microscopy seems to be a reliable method to follow changes in the elemental composition of fluids.
Aging↗
Sarcoplasmic bodies in distal myopathy compared with nemaline rods.
Sarcoplasmic bodies in a late onset distal myopathy and rods in nemaline myopathy have been investigated by electron probe X-ray microanalysis correlated to light microscopy. Sarcoplasmic bodies were glassy, drop-shaped structures up to 10 microns of length and easily distinguished in the scanning mode of electron microscopy performed on thick freeze-dried cryosections. They were found to be source of X-ray spectra characterized by a high sulfur peak. On semithin epoxy sections the sarcoplasmic bodies were observed in the scanning transmission mode as electron-dense structures which, according to X-ray microanalysis, exhibited a high sulphur and osmium content, possibly indicating the presence of sulphydryl groups. The nemaline rods were of 3 different types as judged by their light-microscopical appearance. They were, however, not visible in the scanning mode of electron microscopy performed on freeze-dried unstained cryosections. There were small differences in the elemental composition between different rods within the same biopsy but these were not systematically related to the differences in morphological appearance.
Adult↗
Is copper hepatotoxic in primary biliary cirrhosis?
In primary biliary cirrhosis (PBC) liver copper retention occurs as a complication of cholestasis. By analogy with Wilson's disease, it has been suggested that copper retention is hepatotoxic in PBC, and this has been the rationale for the use of D-penicillamine in this disease. The hypothesis that copper is hepatotoxic in PBC has not been tested and in this study we have evaluated the role of liver copper retention in the pathogenesis of PBC. Sixty-four patients with PBC have been studied. Fifty-four had increased liver copper concentrations. Liver cell synthetic function was well preserved. All the patients had normal prothrombin times, and only two had subnormal serum albumin concentrations. There was no correlation between liver copper concentrations and the degree of liver cell damage assessed biochemically (aspartate transaminase), and histologically. Electron microscopy was performed on liver biopsies from five patients with markedly increased liver copper concentrations. The liver cell ultrastructure was compatible with cholestasis. Liver cells contained electron dense lysosomes, which were shown to contain copper and sulphur by x-ray probe microanalysis. The characteristic organelle changes associated with copper toxicity in Wilson's disease were not observed. The biochemical, histological, and histochemical differences between PBC complicated by liver copper retention, and Wilson's disease, indicates that there are differences in the handling of copper in these disease. In this study we could find no evidence to suggest that copper plays an important role in the pathogenesis of liver dysfunction in PBC.
Copper↗
Deterioration of the elemental composition of endolymph in genetic inner ear disease.
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Age Factors↗
Histochemical and X-ray microanalytical investigations of defined organs and cells in their true position within whole-body cryosections.
Large cryosections (up to 45 x 15 cm) have been made from an entire rat or hamster or from a large human organ such as a cross section of a leg obtained from amputation operations. The quality of the sections was found to be sufficient for a histochemical and a X-ray microanalytical characterization of individual cells in the tissues of interest. When histochemical stainings were applied on sections from a human leg, different muscle groups were analysed simultaneously for pathological changes and at the same time bone tissue, nerves and blood vessels could be investigated. It was possible to study pathological changes in relation to histochemical muscle fibre type and describe the dispersion of changes within a certain muscle. Analytical scanning electron microscopy (X-ray microanalysis) was useful for the description of the elemental composition of different organs on longitudinal sections of small animals and of different muscle fibres in the leg cross sections. The X-ray emission could be related to histochemical muscle fibre type and other parameters such as the degree of fibre atrophy.
Animals↗
Studies on the rat liver following iron overload.
Sprague-Dawley rats were given Jectofer injections to obtain iron overload in rat liver Kupffer and parenchymal cells. The release of iron was studied on the light and electron microscopical level by bleeding of the iron loaded animals and comparing the results with non bled controls. During the mobilization of iron. Kupffer cells showed a rapid and almost complete disappearance of electron dense iron containing particles (IP) while there was only limited decline of IPs in the parenchymal cells. Iron was demonstrated with X-ray microanalysis at the ultrastructural level, and presence of acid phosphatase was revealed using a histochemical method based on precipitation of lead phosphate at sites of enzyme activity in combination with X-ray microanalysis. It was demonstrated that all IP-containing cytoplasmic bodies also showed presence of acid phosphatase implying that all of them represented lysosomes. The mechanism of release of iron from Kupffer and parenchymal cells was discussed with special emphasis on the role of the lysosomes and the relationship between their contents and other cellular structures.
Acid Phosphatase↗
Development of endolymph during maturation of the mammalian inner ear. A preliminary report.
The development of the elemental composition in the endolymphatic space was investigated during embryologic and early post natal maturation of the CBA/CBA mouse. At birth the elemental distribution was similar in the endo- and perilymphatic spaces. Mature composition of endolymph was reached 6--8 days post partum. The maturation of endolymph corresponded well in time with the morphological maturation of the stria vascularis.
Age Factors↗
Studies on the rat liver following iron overload. Electron probe x-ray microanalysis of acid phosphatase and iron.
Previous electron-microscopic studies on the liver have shown that following excessive administration of iron to experimental animals, small particles believed to represent ferritin and/or hemosiderin (electron-dense iron-containing particles [IPs]) accumulate in membrane-bound bodies--many with a lysosome-like structure--in liver parenchymal and Kupffer cells. Further identification of the IP-containing bodies has been facilitated by the application of histochemical techniques for the demonstration of acid phosphatase. The results have shown that reaction product was deposited over organelles similar in appearance to the IP-containing ones, indicating that they were lysosomes. However, the granular nature of the reaction product makes it difficult or impossible to decide whether IPs are present simultaneously with reaction product in the organelle. In order to clarify this qualitative aspect, x-ray microanalysis has been utilized to identify iron and lead (reaction product) in the various structures thought to represent lysosomes. The results indicate that all IP-containing bodies also show the presence of reaction product, and thus can be regarded as lysosomes. However, in the parenchymal cells there may exist a small population of iron-deficient lysosomes (only lead could be shown). The latter may correspond to "primary lysosomes."
Acid Phosphatase↗
Electron probe X-ray microanalysis of human muscle biopsies.
The elemental composition of human muscle fibres have been determined by electron probe microanalysis. In order to distinguish between different types of fibres, two approaches were used. In one approach individual fibres were isolated, portions of them used for a typing by histochemical methods and the main part used for X-ray microanalysis. In the other approach the muscle biopsy was serial-sectioned, some sections used for a histochemical typing and the others (16 micrometer thick cryosections) used for X-ray microanalysis in th eelectron microscopy. The comparison of the ratios between P, S and K in Study No. 1 and 2 indicates different concentrations of sulphur in the subsarcolemmal zone and in the interior of the fibre. Both routes give information on all elements (except the ten lightest ones) contained in the fibres or in sections of them, provided the concentration is high enough. In order to obtain quantitative data, expressed as mmol/kgw, the spectra of the specimens were compared to those of standards of known composition and the data subjected to a so called ZAF-correction (corrections for the atomic number effect, absorption of X-rays in the specimen and secondary fluorescence). Quantitative data concerning phosphorus, sulphur, chlorine and potassium were obtained in Study No. 2. A significantly higher sulphur concentration was found in type IIA muscle fibres as compared to those of type I.
Chlorine↗
Calcium and sulfur location in human nail.
Analytical electron microscopy was performed in order to elucidate the importance of calcium and sulfur to the hardness of nails. The free surfaces adsorb a considerable quantity of calcium from the environment. It is suggested that such adsorption occurs due to ion exchange. This concept is supported by the fact that the distribution of sulfur does not vary over the nail cross-section. Analytical electron microscopy offers unique possibilities of elemental distribution analysis in tissue fragments or sections from keratinized tissues.
Calcium↗
Fine structure of single fibres of human skeletal muscle.
Individual muscle fibres were separated from freeze-dried needle biopsies and classed as type I or type II fibres according to their myofibrillar ATP-ase. Portions of the same fibres were processed for electron microscopy and their fine structure examined. Type I fibres were found to have thicker Z-bands and more mitochondria and lipid droplets than the type II fibres.
Adenosine Triphosphatases↗
Ultrastructure of skeletal muscle in patients with Parkinson's disease and upper motor lesions.
Ultrastructural studies of muscle biopsies from the vastus lateralis of the quadriceps in seven patients with Parkinson's disease and six patients with upper motor lesions are presented. All patients showed varying degrees of mitochondrial changes. Loss of outer membranes or abnormal inner membranes were observed alone or in combination. A reduced number of mitochondria was also noted in some cases. A disorder of filaments was seen. It is assumed that the mitochondrial changes are connected with the altered oxidative capacity previously observed in these patients.
Adult↗
Coronary artery disease in Vietnam casualties.
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Adolescent↗