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  • 1
    ISSN: 1573-5125
    Keywords: Sediment toxicity ; bioluminescent bacteria ; sediment contamination ; macrofaunal communities ; Sado estuary ; Portugal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This paper presents the results from a sedimentary survey undertaken in July 1992 in the Sado estuary, western coast of Portugal. Sediment samples were taken at 14 sites, corresponding to four organic enrichment gradients, three of which are located close to harbour facilities or to industrial or urban effluent outfalls. The fourth site is located away from direct sources of anthropogenic disturbance. An integrated approach was conducted in order to study the quality status of the superficial sediments, and included 1. the analysis of sediment descriptors and contaminants (grain-size, total organic matter, heavy metals, PCBs), 2. the evaluation of toxicity, using bioluminescent bacteria and the Microtox® solid-phase protocol and 3. the study of macrofaunal communities structure and composition. Most of the sediments showed low IC50 values (high toxicity), while benthic macrofauna did not indicate community disturbance in most of the sites, nor the contaminants analysed provided explanation for the potential toxicity observed. Most of the sediments showed high fines content. A statistical significant relation between fines and IC50 values was found, indicating the sensitivity of the toxicity assessment method for granulometry. This sensitivity might explain the lack of agreement between the IC 50 values and the sediment chemistry-infaunal communities structure. The potential grain-size sensitivity was further analysed using another test sediment from which artificial samples with different sand∶fines ratios were prepared. It is concluded that extreme caution should be used when applying the solid-phase Microtox® protocol to assess the toxicity of natural sediments, covering a range of granulometry and contamination situations.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Macromolecules 27 (1994), S. 7650-7653 
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Inflammation research 5 (1975), S. 460-460 
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Inflammation research 5 (1975), S. 461-461 
    ISSN: 1420-908X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 140 (1973), S. 109-128 
    ISSN: 1432-0568
    Keywords: Autonomic nervous system ; Gastrointestinal tract ; Adrenergic nerves ; Anal sphincter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The anatomy and the adrenergic innervation of the rectum, internal anal sphincter and of accessory structures are described for the guinea-pig. The distribution of adrenergic nerves was examined using the fluorescence histochemical technique applied to both sections and whole mount preparations. The longitudinal and circular muscle of the rectum and the muscularis mucosae are all supplied by adrenergic nerve terminals. The density of the adrenergic innervation of the muscularis externa increases towards the anal sphincter. There is a very dense innervation of the internal anal sphincter, of the anal accessory muscles and of the corrugator ani. Non-fluorescent neurons in the ganglia of the myenteric plexus are supplied by adrenergic terminals. The ganglia become smaller and sparser towards the internal anal sphincter and non-ganglionated nerve strands containing adrenergic axons run from the plexus to the sphincter muscle. Adrenergic fibers innervate two interconnected ganglionated plexuses in the submucosa. Very few adrenergic nerve cells were found in the myenteric plexus and they were not found at all in the submucosa. The extrinsic arteries and veins of the pelvic region are heavily innervated by adrenergic nerves. Within the gut wall the arteries are densely innervated but there is little or no innervation of the veins.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-0568
    Keywords: Autonomic nervous system ; Adrenergic nerves ; Pelvic viscera ; Gastrointestinal tract
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The adrenergic innervation of the pelvic viscera was examined by the fluorescence histochemical technique, applied to tissue from untreated guinea-pigs and from guinea-pigs in which nerve pathways had been interrupted at operation. It was found that adrenergic neurons in the inferior mesenteric ganglia give rise to axons which run in the colonic nerves and end in the myenteric and submucous plexuses and around the arteries of the distal colon. In the rectum, part of the innervation of the myenteric plexus and all of the innervation of the submucous plexus comes from the inferior mesenteric ganglia. The rest of the adrenergic innervation of the myenteric plexus comes from the posterior pelvic ganglia or the sacral sympathetic chains. The innervation of the blood vessels of the rectum is from the posterior pelvic ganglia. Adrenergic nerves run from the sacral sympathetic chains and pass via nerves accompanying the rectal arteries to the internal anal sphincter. Other adrenergic fibres to the internal anal sphincter either arise in, or pass through, the posterior pelvic plexuses. The anal accessory muscle is innervated by adrenergic axons arising in the posterior pelvic plexuses. Adrenergic nerves which run in the pudendal nerves, probably from the sacral sympathetic chains, innervate the erectile tissue of the penis.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-0568
    Keywords: Autonomic nervous system ; Adrenergic nerves ; Chromaffin cells ; Pelvic viscera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The organs of the lower abdominal and pelvic regions of the guinea-pig receive nerves from the inferior mesenteric ganglia and pelvic plexuses. The inferior mesenteric ganglia connect with the sympathetic chains, the superior mesenteric ganglia, the pelvic plexuses via the hypogastric nerves, and with the gut. Each pelvic plexus consists of anterior and posterior parts which send filaments to the internal generative organs and to the rectum, internal anal sphincter and other pelvic organs. The pelvic nerves enter the posterior plexuses, which also receive rami from the sacral sympathetic chains. The adrenergic neurons of the pelvic plexuses are monopolar, do not have dendrites and are supplied by few varicose adrenergic axons. Nearly all the nerves contain adrenergic fibres. After exposure to formaldehyde vapour the chromaffin cells appear brightly fluorescent with one or two long, often varicose, processes. Most of the chromaffin cells are in Zuckerkandl's organ or in chromaffin bodies associated with the inferior mesenteric ganglia. Groups of chromaffin cells are found along the hypogastric nerves and in the pelvic plexuses; they become smaller and fewer as regions more posterior to Zuckerkandl's organ are approached.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1432-0533
    Keywords: Mucopolysaccharidosis I Scheie phenotype ; Bone marrow transplantation ; Fibroblasts ; Stereologic analysis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Bone marrow transplantation (BMT) has been used therapeutically in several types of mucopoly-saccharidoses (MPS) and other inherited metabolic disorders. Fibroblasts are severely affected in MPS due to the intralysosomal accumulation of glycosaminoglycans. We report a stereological and morphometric study at light and electron microscopy levels of dermal fibroblasts before and 21 months after BMT in a young girl with MPS I Scheie phenotype (MPS I-S). Dermal fibroblasts showed remarkable morphological changes although their density, expressed as number of fibroblasts per unit volume of dermis (number density), was not modified in the post-BMT samples as compared to pre-BMT ones. Stereological and morphometric parameters referring to cell characteristics of post-BMT fibroblasts (nuclear and cell surface densities, and both nucleus/cell and cell/nucleus volume densities) showed significant differences when compared with pre-BMT fibroblasts, and non-significant differences regarding control cells. On the other hand, quantitative parameters of the lysosomal compartment from post-BMT fibroblasts showed intermediate values between pre-BMT and control fibroblasts. These results, at cellular level, are in agreement with previous biochemical and clinical results, and clearly showed a progressive course to a non-pathological state. All parameters estimated may be considered useful tools in evaluating the success of BMT. These parameters provide quantitative data which can be statistically compared, showing the changes due to the reduction of storage material after BMT. Cell/nucleus volume density is especially interesting since not only is it easy to estimate, even by automatic procedures, but it could also constitute a numerical expression of skin anatomopathological analyses performed post-BMT.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1432-0533
    Keywords: MPS I-S ; Skin biopsy ; Ultrastructure ; Bone marrow transplant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An 11-year-old girl with mucopolysaccharidosis I Scheie phenotype (MPS I-S) received a bone marrow transplant (BMT) from her heterozygous HLA-identical LMC-non-reactive mother. Multidisciplinary studies were carried out and results evaluated 21 months after transplantation. Herein we report the ultrastructural findings pre-and post-BMT in skin. Multidisciplinary studies are commonly used to evaluate the benefits of metabolic correction following BMT in some MPS and other inherited metabolic disorders, and changes in morphology have been described in liver and few other tissues. In this case, we elected skin, since connective tissue is universally involved in MPS and is safely and easily obtainable. Comparison of skin biopsy specimens taken before and after BMT showed a considerable change in dermal fibroblast morphology, with marked reduction in cell size and the number and size of abnormal lysosomes, thus indicating the clearance of storage. Our results demonstrate that dermal cells respond to enzyme replacement therapy in MPS I-S, with the clearance of glycosaminoglycan lysosomal accumulation in connective tissue fibroblasts, which had near-normal morphology 21 months after BMT. Therefore, the practice of skin biopsy after BMT in MPS and other metabolic disorders in which dermal cells are involved should be encouraged.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 33 (1998), S. 283-297 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The kaolin deposits of the Amazon region of Brazil are of lateritic origin, modified by subsequent reduced lacustrine and/or swamp environment. They are contemporaneous with lateritic bauxites found in the same region, all formed from aluminium silicate rocks. These are principally sedimentary rocks from the Cretaceous period (Itapecuru and Alter do Chão), but also include metamorphic and felsic volcanic rocks. After erosion of the upper part of these profiles they became locally a substratum for swampy and/or lacustrine environments mostly developed over the clayey saprolitic horizon where kaolin occurs. The saprolitic horizon is made up mainly of iron-mottled kaolinite which has been subject to an intense deferrification, which has increased the kaolin brightness and thickness. The kaolins are basically made up of well-crystallized kaolinite, quartz, sometimes illite-muscovite, anatase and hematite. In certain locations, crandallite-goyazite is also present. The deposits studied differ from each other in the mineral content levels, concentration of principal elements and in trace element distribution. The greatest quantity of quartz and, consequently SiO2, is intrinsically related to the type of parent rock. Small sedimentary deposits occur in alluvial flood plains located not very far from the lateritic source.
    Type of Medium: Electronic Resource
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