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  • 1980-1984  (227)
  • 1981  (227)
  • Ultrastructure  (126)
  • Rat  (109)
  • Nuclear reactions
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 393 (1981), S. 133-144 
    ISSN: 1432-2307
    Keywords: Term, normal human placenta ; Fetal arteries ; Ultrastructure ; Specialized processes of smooth muscle cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Fetal stem arteries of the 3rd order of 50 normal placentas obtained at term of unevenful pregnancies were examined by transmission electron microscopy with the aim at providing a base-line information for the assessment of similar arteries in hypertensive disorders of pregnancy. The results showed that the endothelial cells often protruded with a considerable portion of their cellular body into the lumen, and that the intercellular junctions between the neighbouring cells were confined largely to their short basal segments. Numerous myoepithelial junctions were formed between the processes of the endothelial cells and those extending from the smooth muscle cells (SMC) of the adjacent medial layer. At times the “participating” processes of the SMC were entirely enclosed within the endothelial body. Collagen fibrils increased in number between the SMC and the interstitium broadened progressively from the inner to the outer arterial layers. Small cellular processes devoided of a basement membrane and of most cytoplasmic organelles were numerous in the interstitium; these were traced to the main bodies of the medial SMC. It is postulated that the “naked” SMC-processes are susceptible to injury of a nature much more subtle than that affecting the main body of the SMC, since these processes were often swollen and appeared edematous in an otherwise innocuous mural environment.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 393 (1981), S. 245-250 
    ISSN: 1432-2307
    Keywords: Malignant melanoma of the vagina ; Malignant melanoma of the cervix ; Malignant melanoma ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This report concerns a very rare case of primary malignant melanoma involving the vagina and cervix uteri occurring in a 45-year-old woman. The clinical, light-microscopic and ultrastructural findings are presented and discussed.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 393 (1981), S. 233-244 
    ISSN: 1432-2307
    Keywords: Adamantinoma of long bone ; Ultrastructure ; Histogenesis ; Mesodermal or mesectodermal origin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron microscopic examination of three adamantinomas of long bones revealed structures usually observed in both mesenchymal and epithelial tumours. Tumour cells showing high alkaline phosphatase activity frequently tended to line clefts in connective tissue, resembling endothelial cells. The long processes of such cells showed fenestration. In areas showing fibre production the tumour cells were in close relationship to collagen fibrils. The latter were found, together with microfibrils, between the processes and above the basement membranes. The tumour cells were interconnected by desmosomes with tonofilaments and contained numerous bundles of microfilaments. All three cases revealed tiny intracytoplasmic inclusions resembling Weibel-Palade endothelial bodies. In addition, some of the structures in the lumena contained definite acid mucosubstances. A squamous cell pattern was present in only one of the three specimens. The coincidence of divergent structures in a single specimen has led us to the conclusion that the so-called adamantinoma of long bone might be possibly related to tumours of mesodermal or mesectodermal origin.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 393 (1981), S. 333-343 
    ISSN: 1432-2307
    Keywords: NHMI ; Pathogenesis ; Lung tumors ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male F344 rats were given 3 mg N-nitrosoheptamethyleneimine (NHMI) per 100 g in olive oil by gavage twice a week for a maximum of 20 weeks. They were killed at predetermined intervals after the start of treatment and the sequential development of NHMI-induced squamous carcinomas in the lungs was followed by light and electron microscopy. Hypertrophy of the endoplasmic reticulum in mucous and Clara cells seen in an initial study suggested that these cells were involved in metabolic activation of the nitrosamine. Basal cells were identified as the cell type that later responded by proliferation, hyperplasia, and squamous metaplasia. Only in the bronchioles, where basal cells are not found in the healthy rat, did these lesions progress further to form squamous cell carcinomas.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    International orthopaedics 5 (1981), S. 47-52 
    ISSN: 1432-5195
    Keywords: Osteoarthritis ; Collagen framework ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Des prélèvements obtenus à partir de genoux humains arthrosiques et de genoux de chien porteurs de lésions arthrosiques expérimentales ont permis l'étude de la charpente de collagène du cartilage articulaire et de l'os sous-chondral, par microscopie conventionnelle et par microscopie électronique. Dans les lésions dégénératives, les fibrilles de collagène du cartilage ont une orientation radiale, alors qu'elles sont habituellement groupées en faisceaux. En cas de lésions étendues, le cartilage présente souvent des clivages ou des fissures menant jusqu'aux couches calcifiées. Les fibrilles de collagène du cartilage arthrosique se fondent dans la plaque osseuse souschondrale, rendant la jonction ostéo-cartilagineuse irrégulière ou mal définie. L'orientation trabéculaire de l'os sous-chondral se modifie en fonction de l'altération du cartilage articulaire. Ces modifications réactionnelles montrent que, même au niveau ultrastructural, l'architecture de l'os sous-chondral reflète la dégénérescence cartilagineuse.
    Notes: Summary Specimens obtained from human osteoarthritic knee joints and dog knees with experimentally induced osteoarthritis were used to study the collagenous framework of articular cartilage and subchondral bone in relation to osteoarthritic changes using scanning electron microscopy and light microscopy. Degenerative articular cartilage in osteoarthritic joints showed radial orientation of the collagen fibrils, which were usually discernible as fibrillar bundle formations. Cartilage with extensive lesions often showed cleavages or fissures down to the calcified layer. The cartilagenous collagen fibrils in osteoarthritic specimens merged into the subchondral bone plate making the tidemark and the osteochondral junction irregular or obscure. The trabecular orientation of subchondral bone changed with alteration in the articular cartilage and with reactive changes in the subchondral bone, showing the effect of cartilaginous degeneration on its ultrastructure.
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  • 6
    ISSN: 1432-2072
    Keywords: Cyclazocine ; Acute treatment ; Dopamine ; Noradrenaline ; Serotonin ; Monoamine metabolites ; Brain regional assay ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of cyclazocine on the metabolism of dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (5-HT) in regions of rat brain were studied by measuring changes in the levels of the monoamines and their major metabolites. Doses ranging from 4–32 mg/kg were tested. Rats were sacrificed 1 or 2 h after administration of the drug, according to the experiment. Administration of cyclazocine significantly decreased DA concentration and increased the levels of DOPAC and HVA in striatum. Cyclazocine decreased the levels of NA, and markedly increased the levels of MHPG-SO4 and 5-HIAA in cortex, hypothalamus, midbrain and pons-medulla, while little change in 5-HT concentration, except a decrease after the highest dose, was observed. These changes in the metabolism of the monoamines differed in their amplitude and temporal nature. The possible roles of dopaminergic, noradrenergic and serotoninergic neurons in different brain regions are discussed in relation to modifications of locomotor activity and the induction of bizarre behavior resulting from cyclazocine administration in rats. These investigations may add to the understanding of the mechanism of psychotomimetic effects produced in man by this drug.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Psychopharmacology 75 (1981), S. 132-133 
    ISSN: 1432-2072
    Keywords: Morphine tolerance ; Log-dose/response curve flattening ; Naloxone prevention ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Male wistar rats, previously made tolerant to morphine by at least 3 weeks of daily intraperitoneal (IP) injections of 20 mg/kg morphine-SO4 (MS), were then given 200 mg/kg MS daily for 4 or 5 days. Tail immersion tests of antinociception, carried out before and after the 200 mg/kg MS treatment, indicated that the additional morphine treatment was followed by a large further decrease in opiate sensitivity, characterized by decreased slope of the log-dose/response curve (LDR curve flattening). The further decrease in opiate sensitivity was substantially reduced by naloxone-HCl (IP) in a dose of 10 mg/kg given 30 min before and 8 h after the 200 mg/kg MS injections, or a dose of 4 mg/kg given 45 min after the MS. It was concluded that LDR curve flattening produced by high doses of MS is mediated by specific opiate receptors, and is a true expression of a high degree of opiate tolerance in the intact rat.
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  • 8
    ISSN: 1432-2072
    Keywords: Cannabis ; catecholamines ; Hyperreactivity ; Hyperthermia ; Pimozide ; Atropine ; 6-OHDA ; Stereotypy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The behavioral responses of the rat to an extract of Cannabis sativa were examined after IP injection of 5, 15 and 30 mg/kg (expressed as Δ 9 tetrahydrocannabinol). The lowest dose of the extract induced stereotyped behavior (rhythmic head movements, intermittent gnawing and sniffing) together with hypersensitivity to stimuli and hyperthermia. The administration of higher doses of the extract resulted, initially, in similar behavioral effects but of greater intensity, followed by a cataleptic state alternating with atonic muscular prostration; rectal temperature was decreased. Pre-treatment with 6-hydroxydopamine (6-OHDA, which produces degeneration of catecholamine-containing nerve terminals) or pimozide (blocker of dopamine receptors) significantly reduced both stereotypy and hyperreactivity. Thermic effects were also antagonized by 6-OHDA pre-treatment. Cannabis-induced catalepsy was enhanced by pimozide but reduced by atropine (3 mg/kg SC). These results support the hypothesis that catecholamines play an important role in the complex behavioral effects of cannabis.
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  • 9
    ISSN: 1432-2072
    Keywords: Rat ; Hippocampus ; Dopaminergic receptors ; Apomorphine ; Haloperidol ; Memory consolidation ; Brightness discrimination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Post-training intrahippocampal injection of the dopaminergic agonists apomorphine and ergometrine improved retention in a brightness discrimination task. The dopamine receptor blocker haloperidol caused an impairment of retention and antagonized improvement by apomorphine. An involvement of hippocampal dopaminergic mechanisms in memory consolidation processes was suggested.
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  • 10
    ISSN: 1432-2072
    Keywords: Superior colliculus ; Oral stereotypy ; Picrotoxin ; Reactivity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Lesions of the superior colliculus in rats attenuate the oral stereotypy produced by systemic administration of dopamine agonists. Current evidence suggests that such drugs affect the superior colliculus by reducing transmission in the inhibitory GABAergic nigrotectal pathway. To investigate whether the superior colliculus plays a direct role in producing stereotyped oral movements, the present experiment therefore examined the effects of collicular microinjections of the GABA antagonist picrotoxin on the behaviour of rats observed in an open-field. Gnawing was observed after injections of picrotoxin (25 ng) into sites in the intermediate and deep layers of the superior colliculus, consistent with the superior colliculus playing a direct part in producing the stereotyped gnawing seen after systemic administration of dopamine agonists. However, gnawing was only observed after a period in which the animal showed strong avoidance reactions, to stimuli that normally evoked orienting or little reaction. This change in reactivity was observed after injections of picrotoxin into all parts of the colliculus, but the most sensitive (responding to doses as low as 12.5 ng) were mainly in the superficial and intermediate layers. It appears that there may be more than one GABAergic system within the superior colliculus.
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  • 11
    ISSN: 1432-2072
    Keywords: 6-Hydroxydopamine ; Sensorimotor deficits ; Superior colliculus ; Picrotoxin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Anatomical and biochemical investigations have suggested that GABA transmission in the superior colliculus consequent upon activity of the nigrotectal pathway is increased following 6-hydroxydopamine (6-OHDA) lesions of the ascending dopamine systems. Moreover, it has been proposed that this increase in inhibitory activity within the colliculus may be responsible for the sensory neglect commonly observed after dopamine denervation. The present experiment sought to test this proposal by examining the effects of injections of the GABA antagonist picrotoxin into the superior colliculus of 6-OHDA lesioned rats, in the hope that the neglect caused by the 6-OHDA would be reversed. However, in 33 of 36 cases studied intracollicular microinjections of picrotoxin produced no detectable improvements in orientation to sensory stimuli, although a wide range of other behavioural effects was observed. These included stereotyped exploratory movements (e.g. head waving, walking, sniffing and rearing) similar to those produced in the 6-OHDA treated rats by systemic injection of apomorphine (0.1 mg/kg). These data indicate that 6-OHDA lesions of substantia nigra and ventral midbrain areas do not produce sensory neglect simply by increasing GABA transmission within the nigrotectal pathway. Instead, such an increase in nigrotectal activity may impair production of particular kinds of movement, possibly related to exploratory behaviour.
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  • 12
    ISSN: 1432-2072
    Keywords: Postnatal treatment ; Haloperidol ; Apomorphine ; Stereotyped behaviour ; Locomotion ; Learning ; DOPAC ; HVA ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats were administered 0.5 mg/kg SC of haloperidol (H) or saline (S) daily from day 1 after birth until 20 days of age. At 60 days of age (40 days after the postnatal treatment with H or S was interrupted) the stereotyped behaviour and the effects on locomotor activity elicited by apomorphine in S- and H-pretreated rats were investigated. The intensity of apomorphine (0.5–1 mg/kg, SC)-induced stereotyped behaviour was significantly greater in the H-pretreated group than in S-pretreated animals and this was accompanied by a much more marked reduction of locomotor activity in H-pretreated than in S-pretreated rats. Finally, at 80 days of age (60 days after the postnatal treatment with H or S was interrupted) rats were subjected to a Differential Reinforcement of Low Rates schedule (DRL 15-s). The results indicate that the acquisition of the DRL task performance criterion (Rs/Rf≤2.5) was significantly more rapid in S-pretreated rats than in H-pretreated ones. In parallel biochemical experiments, acute H produced smaller increases in dopamine turnover in chronic H-treated rats compared with S-treated controls. These data indicate that H treatment in neonatal rats induces behavioural and biochemical changes which can be observed up to 60 days after H withdrawal.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Psychopharmacology 74 (1981), S. 275-279 
    ISSN: 1432-2072
    Keywords: Animal model ; Tremor intensity ; Quantification ; Physostigmine ; Atropine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A simple and accurate device for recording tremor intensity in unanaesthetized and unrestrained rats is described. The physical measures of tremor are shown to have several advantages over previous devices. First, the new apparatus, unlike some earlier ones, does not restrict the animal's movements to an unusually small cage, with weighty mechanical devices or with electrical leads. Second, most earlier methods for measuring tremor use a subjective rating scale. However, the present method uses objective and reliable measures. In a double-blind, illustrative experiment involving complete crossover, Wistar rats were randomly injected IP with physostigmine in doses of 0.2, 0.4, 0.6 and 0.8 mg/kg or the corresponding amount of 0.9% NaCl solution as control. The recorded tremor intensity showed a clear dose-response relationship for physostigmine. Moreover, linear regression of the dose-response relationship showed that tremor intensity increased linearly with increasing doses of physostigmine. The cholinergic antagonist atropine (0.3 mg/kg SC) antagonized physostigmine-induced tremor, whereas methylatropine (0.3 mg/kg SC) tended to potentiate it. These results show that the technique described is suitable for quantification of tremor intensity in rats and for testing drug interactions on physostigmine-induced tremor.
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  • 14
    ISSN: 1432-2072
    Keywords: Hippocampal units ; Cortical EEG ; Ethanol ; Adrenergic antagonists ; GABAergic antagonists ; Cholinergic agonists ; Dopaminergic agonists ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The spontaneous activity of single unit populations in the dorsal hippocampus and the cortical EEG were monitored in the awake rat. Experiments consisted of three consecutive recording periods; a drug-free baseline period, a pretreatment period and an ethanol period. Pretreatment with doses of dopaminergic or cholinergic agonists, which produced decreases in unit rate and an awake EEG attenuated the inhibitory effect of ethanol on hippocampal unit activity and reduced the amount of high-amplitude, slow (HAS), drowsy-state activity. GABAergic and adrenergic antagonists, which increased hippocampal unit rate, did not attenuate and sometimes enhanced the ethanol-induced inhibition in firing rate but had little additional effect on the EEG. These results point to the involvement of hippocampal neurons in those behavioural aspects of ethanol intoxication mediated by activity in the neurotransmitter systems examined here.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 392 (1981), S. 34-39 
    ISSN: 1432-2013
    Keywords: Erythropoietin ; Erythropoiesis ; Kidney ; Hypoxia ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Controversial hypotheses exist as to whether hypoxic kidneys produce biologically active erythropoietin (Ep) or an inactive erythropoietic factor that generates Ep from plasma protein in the blood. To clarify the role of the kidney in Ep production we attempted to extract Ep from kidneys of normal and of hypoxia exposed (6 h at 0.42 atm) Sprague-Dawley rats. Ep was measured in the microsomal fraction of kidney homogenates, using the exhypoxic polycythemic mouse assay for Ep. The Ep content was also determined in kidneys that were flushed free of blood with isotonic phosphate-buffer prior to extirpation. We found 0.04 U Ep/g in blood-depleted kidneys of normal rats. Upon exposure of the animals to hypoxia the Ep level increased to 0.92 U/g kidney. Ep levels were significantly higher in the kidney cortex than in the medulla. The erythropoietic activity in renal extracts was not enhanced after incubation of samples with homologous serum. Ep extracted from hypoxic kidneys behaved identically with plasma-Ep in the following biochemical tests: heat stability, affinity chromatography with wheat germ lectin, ion exchange chromatography, molecular sieve chromatography and neuraminidase inactivation. These studies support the hypothesis that kidney cortex cells are capable of producing biologically active Ep.
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  • 16
    ISSN: 1432-5233
    Keywords: Fourth cell type ; Islet cell types ; Pancreatic islets ; Pancreatic polypeptide ; Rat ; Somatostatin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An argyrophilic fourth cell type in fetal and adult rat pancreatic islets can be identifed by using a modification of the Grimelius silver statin. This cell is much more abundant in the fetal pancreas than in the adult. By employing the modified silver technique followed by restaining with the indirect immunofluorescent procedure for somatostatin, the content of this argyrophilic fourth cell was studied further. Comparison of these histochemical studies demonstrated that somatostatin was not located in the fourth cell of either the adult or fetal rat pancreas. These results indicate that the D-cell and the fourth cell type are not the same cell. Thus far the only product associated with this argyrophilic cell is pancreatic polypeptide. As a result this cell probably represents the PP-cell of the Wiesbadan classification.
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  • 17
    ISSN: 1432-2307
    Keywords: Granulocytic sarcoma ; Chloroma ; Meningeal sarcoma ; Ultrastructure ; Myelogenous leukemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An unusual case of meningeal granulocytic sarcoma without evidence of Leukemia is presented. The patient, a 40 year old female, presented with a chronic subdural haematoma. Three months later a large meningeal tumor was discovered adjacent to the previous haematoma and was found to be a granulocytic sarcoma by the use of electron microscopy. The tumor was treated by surgical excision followed by radiotherapy and chemotherapy. The patient remains free of symptoms and without evidence of leukemia in the peripheral blood or bone marrow 9 months after the diagnosis was established. The ultrastructural findings in the tumor and diagnostic difficulties often encountered are emphasized.
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  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 392 (1981), S. 97-104 
    ISSN: 1432-2307
    Keywords: Reducing body myopathy ; Classification ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die sog. reducing body myopathy, eine sehr seltene progressive muskuläre Krankheit, zeigt neben einer unspezifischen herdförmigen Muskelfaserdegeneration als typisches morphologisches Merkmal Muskelfasereinschlüsse, die reduzierende Eigenschaften aufweisen. Die nosologische Einordnung des Krankheitsbildes blieb bisher ungeklärt. Es wird über ein 15 Jahre altes Mädchen mit einer zunehmenden allgemeinen Muskelschwäche und Muskelatrophie berichtet, bei dem in der Muskelbiopsie neben unterschiedlichen regressiven Veränderungen zahlreiche Fasereinschlüsse beobachtet wurden, die u.a. in der Lage sind, ohne Substrat Tetrazoliumsalze in Gegenwart von Menadione zu reduzieren. Feinstrukturell sind diese Einschlüsse aus Granula von 12–16 nm Durchmesser zusammengesetzt. Eine Schwester der Erkrankten leidet seit vielen Jahren an einer klinisch und morphologisch gleichartigen Krankheit. Die sog. reducing body myopathy muß daher in die Gruppe der congenitalen Myopathien mit strukturellen Besonderheiten eingeordnet werden. Nachdem darüber hinaus bei anderen Muskelkrankheiten ebenfalls Fasereinschlüsse mit reduzierenden Eigenschaften vorkommen können, die jedoch in ihren übrigen strukturellen und histochemischen Eigenschaften keine Übereinstimmung mit den bei der sog. reducing body myopathy nachweisbaren Inclusionen besitzen, sollte das Krankheitsbild nach seinem führenden morphologischen Merkmal, den offenbar nur hier vorkommenden granulären Fasereinschlüssen, benannt werden. Es wird vorgeschlagen, die sog. reducing body myopathy als Granularkörpermyopathie zu bezeichnen.
    Notes: Summary Reducing body myopathy is a very rare progressive muscular disease. Apart from a non-specific circumscribed muscle fiber degeneration it displays muscle fiber inclusions which have reducing properties as a typical morphological feature. The nosological classification of the disease is not settled. A case in a 15 years old girl is reported. She suffered from a progressive muscular weakness and atrophy and in a muscle biopsy regressive changes were obvious. Furthermore, multiple eosinophilic muscle fiber inclusions were also observed, which exhibited reducing properties. They consist of electron dense granules with a diameter of 12–16 nm. Since a sister of the patient has suffered for many years from a clinically and morphologically similar muscle disease, reducing body myopathy apparently belongs to the group of congenital myopathies with structural abnormalities. Muscle fiber inclusions with reducing properties also occur in another myopathy, in which they structural and histochemical differ widely from those found in reducing body myopathy. The reducing body myopathy is better named after its typical morphological property, the granular inclusions. It is proposed to name it “granular body myopathy”.
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  • 19
    ISSN: 1432-2307
    Keywords: Urinary bladder adenocarcinomas ; ABH isoantigens ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neoplastic and non-neoplastic tissue specimens from ten patients with primary adenocarcinoma of the urinary bladder were examined. Most of these tumors were associated with either foci of transitional cell carcinoma and/or with glandular metaplasia of the bladder epithelium. The mucin produced by the neoplastic cells was PAS, alcian blue, mucicarmine, PB/KOH/PAS, and RPB/KOH/PAS-positive. ABH isoantigens of these tumors were not always deleted. Ultrastructurally, the neoplastic cells resembled goblet cells. Their plasma membrane had numerous microvilli with prominent glycocalyx. Proliferation and attenuation of tight junctions were noted. The gap junctions were few and small. Two types of desmosomes were found. The ultrastructural features of the neoplastic cells were attributed in part to the malignant transformation and in part to the direction of their differentiation. We have not observed any distinctive morphologic, histochemical, immunologic or ultrastructural features that might be diagnostic for these adenocarcinomas.
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 394 (1981), S. 167-176 
    ISSN: 1432-2307
    Keywords: Malignant fibrous histiocytoma ; Sarcoma ; The lung ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of malignant fibrous histiocytoma of the lung is reported. The tumour margin was well circumscribed, showing an expanding border and no capsule. The main part of the tumour was composed of spindle-shaped fibroblast-like cells arranged in broad fascicles with a partially storiform pattern. Other parts of the tumour were arranged in a haphazard pattern, containing many mononucleated and multinucleated giant cells. Ultrastructurally six differnt cell types were encountered. The dominant type was a fibroblast-like cell; also present were many giant cells and some histiocyte-like cells, together with their intermediate forms, and few undifferentiated mesenchymal cells. We consider this tumour to have developed from the peribronchial connective tissue; it has the same cellular composition as the malignant counterpart arising in soft tissues.
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  • 21
    ISSN: 1432-2307
    Keywords: Cyclic hematopoiesis ; Bone marrow ; Ultrastructure ; Nuclearcytoplasmic asynchrony ; Döhle-like bodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The pathogenesis of cyclic hematopoiesis (CH) in the grey collie dog is still unknown. It has been proposed that periodic bursts of necrosis of the bone marrow neutrophils would induce cyclic arrests of the stem cell differentiation. In the present study, the sequential changes undergone by the erythroid and neutrophil series of the bone marrow of CH dogs were evaluated by electron microscopy. Erythroid cells presented quantitative periodic oscillations but the morphologic features of both immature and mature cells were normal. On the contrary, nonspecific necrotic changes were observed to occur in the myeloid series. Those abnormalities, which were more marked between days 9 and 11 of the cycle, mainly involved the immature cells and, to a lesser extent, the mature neutrophils. The number of necrotic cells was variable in different cycles, but always represented a small portion of the myeloid cells. In addition, few bone marrow macrophages displayed signs of phagocytic activity containing cell debris. The ultrastructural changes of the myeloid series were accompanied by an abnormal decrease of peroxidase activity and the permanence of large acid phosphatase-positive Golgi complexes in mature neutrophils, as defined by morphologic criteria. Döhle-like arrays of rough endoplasmic reticulum were present in many cells. Our findings suggest that an asynchronic development of myelocytes occurs as a result of regulatory abnormalities related to the congenital defect of the bone marrow which interferes with the differentiation and maturation of the stem cells. Necrosis in some myeloid cells would be a secondary phenomenon rather than a causal factor for the cyclic arrest of cell maturation as has been previously submitted. Furthermore, the small size of the necrotic cell population could not justify the production of “inhibitors” in sufficient amounts as to block the normal evolution of the bone marrow stem cell pool.
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  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 391 (1981), S. 33-44 
    ISSN: 1432-2307
    Keywords: Carcinoid heart disease (carcinoid syndrome) ; Endocardial plaque ; Endocardial lesion ; Ultrastructure ; Myofibroblast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei einer 67jährigen Patientin mit einem metastasierenden Dünndarmcarcinoid fanden sich bei der Autopsie die für das Carcinoidsyndrom typischen Endokardveränderungen der rechten Herzhöhlen. Anhand dieses Falles und des Schrifttums wird über die Ultrastruktur der endokardialen Auflagerungen beim Carcinoidsyndrom berichtet. Charakteristisch für diese Auflagerungen ist die Proliferation von glatten Muskelzellen und Myofibroblasten, die von reichlich basalmembranähnlichem Material umgeben sind und vereinzelt durch Maculae adhärentes untereinander verbunden sind. Die Grundsubstanz ist aus sauren Mucopolysacchariden, normalen kollagenen Fibrillen und Mikrofibrillen aufgebaut. Die Verdickungen unterscheiden sich morphologisch von allen anderen Endokardveränderungen, unter anderem durch das Fehlen von amorphem Elastin. Ihre Entstehung im Zusammenhang mit der endokrinen Aktivität der Carcinoide wird diskutiert.
    Notes: Summary In a 67-year-old female patient with metastasising carcinoid of the small intestine there were right-sided endocardial plaques characteristic of the carcinoid syndrome. Ultrastructurally, the lesions showed proliferation of smooth muscle cells and myofibroblasts, which were surrounded by basementmembrane-like material and occasionally showed intercellular connections of the macula adhaerens type. The ground substance consisted of acid mucopolysaccharides, normal collagen fibrils, and microfibrils. The endocardial plaques in the carcinoid syndrome differ morphologically from other endocardial lesions by the lack of amorphous elastin. The formation of plaques and its relation to the endocrine activity of the carcinoid tumors is discussed, and pertinent literature is reviewed.
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    Virchows Archiv 392 (1981), S. 199-216 
    ISSN: 1432-2307
    Keywords: Aortic media ; Human ; Ultrastructure ; Elastin ; Smooth muscle cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructural organization of the adult human aortic media was studied utilizing aortic biopsies from 14 patients, ranging in age from 28 to 67, who underwent cardiac surgery. Apart from solid elastic elements the tissue spaces contained a vast amount of ill-defined thin streaks of elasin, an observation much facilitated by utilizing a selective elastin staining technique. In favorable sections, these streaks were found to be continuous with the solid elastic laminae. Furthermore, most medial smooth muscle cells were in close contact with the thin streaks, but almost none directly with the elastic laminae. The smooth muscle cells had also virtually no connection with collagen fibers. These observations are in contrast with the organization of elastin and with cell-to-stroma connections in the more extensively studied rodent and porcine aortas; they bring into question the role of the smooth muscle cells in the regulation of the viscoelastic properties of the human aortic wall. Other findings were: large number of nexuses connecting the smooth muscle cells, a very small degree of smooth muscle cell degeneration, and the presence of flocculent, fine-granular material investing all formed elements, but especially associated with the thin streaks of elastin.
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  • 24
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    Virchows Archiv 390 (1981), S. 181-191 
    ISSN: 1432-2307
    Keywords: Experimental islet cell tumour ; Streptozotocin ; Immunohistochemistry ; Ultrastructure ; Cellular dedifferentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Fourteen rat islet tumours induced by Streptozotocin and nicotinamide were examined by light microscopy with indirect immunoperoxidase staining and by electron microscopy. Most tumours consisted predominantly of B cells, but over a half of the tumours examined showed mixed cellularity with considerable numbers of A cells and small numbers of D or PP cells. Only 4 tumours consisted exclusively of B cells. There was no positive reaction for any kind of specific islet hormone antibodies in 2 tumours. Ultrastructurally, most tumours were composed of cells containing numerous secretory granules with B cell properties, with great variation in size, shape and number. We often encountered enterochromaffin-like cells or atypical granular cells or cells containing non-beta secretory granules. We could not identify, however, the ultrastructural counterparts of A or D cells. The results suggested that the multiplicity of the endocrine cells of rat islet cell tumours might be an expression of the cellular dedifferentiation of tumour cells which could re-differentiate into the whole range of components of the endocrine pancreas.
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  • 25
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    Virchows Archiv 391 (1981), S. 291-299 
    ISSN: 1432-2307
    Keywords: Submandibular gland ; Rat ; Irradiation ; Enzyme histochemical study ; Ultrastructural study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Single-dose cervical irradiation by cobalt 60 in rats induced lasting functional disturbances of the submandibular gland which were excessive when compaired with the relative integrity of the gland as seen under the light microscope. Enzyme histochemical and ultrastructural studies revealed severe damage shortly after exposure with appearance of karyolytic bodies and autophagosomes accompanied by increased hydrolase activity. Mitochondrial alterations were concomitant with diminished ductal oxidative enzyme activity. Although most of these alterations resolved rapidly as a result of acinar and ductal cell repair and regeneration originating in the intercalated ducts, secretory abnormalities were still observed two months after exposure as evidenced by the accumulation of granules in acinar cells and the heterogeneity of ductal cell granules. These anomalies, comparable to those observed in sialadenoses, probably result from persistent alterations of intralobular nerve endings.
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  • 26
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    Virchows Archiv 391 (1981), S. 363-369 
    ISSN: 1432-2307
    Keywords: Tuberous sclerosis ; Spleen ; Ultrastructure ; Glial fibrillary acidic protein (GFAP)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Three cases of tuberous sclerosis in neonates were found to have focal, frequently perivascular, collections of large cells with abundant eosinophilic cytoplasm. These cells resembled those found in brain lesions of tuberous sclerosis but did not stain for acidic protein. Ultrastructurally, they were characterized by many membrane bound cytoplasmic bodies, 90 to 270 nm in diameter, with amorphous contents. Filaments were not demonstrated. Their appearance is considered most consistent with histiocytic origin. Large cells with a histiocytic appearance and a superficial resemblance to those seen in the brain in tuberous sclerosis, but a different ultrastructure and reaction to GFAP staining, may be found in the spleen of neonates with this disease.
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  • 27
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    Virchows Archiv 393 (1981), S. 103-114 
    ISSN: 1432-2307
    Keywords: Cerebro-hepato-renal (Zellweger-) syndrome ; Morphological diagnosis ; Ultrastructure ; Peroxisomes ; Autopsy ; Catalase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A female newborn, the second child of healthy non consanguineous parents, exhibited muscular hypotonia, areflexia, apathy, seizures, hepatomegaly and failure to thrive since birth. The peculiar skull shape was lacking. In the urine pipecolic acid and trihydroxycoprostanoic acid were excreted. At the age of seven weeks she died of bronchopneumonia. Lightmicroscopy revealed malformations and deficiency of myelinisation in the brain, renal cysts and fatty metamorphosis in the enlarged liver, which showed only minimal siderosis. Ultrastructurally no peroxisomes could be found in liver and kidney. No peroxisomes were detected by histochemical demonstration of catalase in frozen liver tissue which was taken immediately after death and stored for three months. Absence of peroxisomes is pathognomonic for the cerebro-hepato-renal syndrome of Zellweger and occurs in the liver irrespective of duration and degree of liver damage. It is best demonstrated by enzymehistochemical electron microscopy. With this method peroxisomes can be visualized even 30 h post mortem. In deep frozen normal liver tissue the activity of catalase remains very stable and enables the identification of peroxisomes even after a 12 months period of storage. In the cerebro-hepato-renal syndrome of Zellweger, frozen liver tissue should be stored for biochemical and diagnostic enzymehistochemical studies.
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  • 28
    ISSN: 1432-1920
    Keywords: Metrizamide ; Conray ; Dimer X ; Subacute inflammatory reactions ; Brain edema ; Ultrastructure ; Arachnoid granulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Adult New Zealand rabbits were injected intrathecally with 200 or 300 mgI/ml of metrizamide, meglumine iocarmate or meglumine iothalamate. They were placed in the Trendelenburg position for 20 min and allowed to survive for 1, 2 or 3 weeks. Sacrifice was by intraarterial perfusion of aldehydes under anesthesia followed by preparation of brain and major venous sinuses for light and electron microscopy. Major findings were subpial edema and inflammatory reaction of superficial brain, leptomeninges, subarachnoid space and arachnoid granulations. They were most severe after iothalamate and milder after metrizamide. The severity decreased with time. It is of significance that severe reactions occurred after 300 mg I/ml concentration of metrizamide.
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  • 29
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    Naunyn-Schmiedeberg's archives of pharmacology 317 (1981), S. 61-66 
    ISSN: 1432-1912
    Keywords: GABA ; Rat ; Thyroid gland ; Transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The uptake of γ-aminobutyric acid (GABA) into rat thyroid slices was studied. 2. Uptake of 14C-GABA was concentration-dependent: one unsaturable (diffusion) and two saturable components obeying Michaelis-Menten kinetics contributed to transport. 3. The kinetic constants of saturable GABA transport systems were: K m1 =1.5 μM, V 1=4.0 nmol×(g wet weight)−1×(20 min)−1 (high-affinity uptake); K m2 =800 μM, V 2=260 nmol×(g wet weight)−1×(20 min)−1 (low-affinity uptake). 4. Uptake mediated by each of the carrier systems was concentrative, entirely Na+-dependent, and required activation energies characteristic for active transport. 5. High-affinity transport was structurally specific for GABA. The substrate specificity of low-affinity uptake resembled that of β-amino acid transport systems.
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    Naunyn-Schmiedeberg's archives of pharmacology 317 (1981), S. 165-167 
    ISSN: 1432-1912
    Keywords: Pentobarbital ; Diazepam ; Plasma amino acids ; Tyrosine ; Tryptophan ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intraperitoneal injections with pentobarbital and diazepam caused an increase in the concentration of most plasma amino acids in rat. In contrast, tryptophan was significantly decreased after treatment with pentobarbital. The tyrosine level showed no change and was thus actually reduced after pentobarbital treatment in relation to the total pool of large neutral amino acids. The possibility should be considered that these changes in plasma amino acid patterns may lead to reduced transport of e.g. tryptophan and tyrosine into the brain, which in turn might retard the synthesis of monoaminergic neurotransmitters. The transport and action of several aromatic amino acids used as therapetic agents may also be influenced.
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  • 31
    ISSN: 1432-1912
    Keywords: Ethanol ; Plasma amino acids ; Adrenalectomy ; Hypophysectomy ; (−)-Propranolol ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In previous studies we have demonstrated that an acute dose of ethanol cause an immediate decrease in most plasma amino acids in both man and rat. This effect of ethanol is partly inhibited by the β-adrenergic antagonist (−)-propranolol, partly by adrenalectomy or hypophysectomy and almost completely by a combination of adrenalectomy with (−)-propranolol. This finding suggests an involvement of both β-adrenergic mechanisms and steroids from the adrenal cortex in the ethanol-induced decrease in plasma amino acids.
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  • 32
    ISSN: 1432-1440
    Keywords: Lipids ; Intestinal mucosa ; Diabetes mellitus ; Biochemistry ; Ultrastructure ; Lipide ; Dünndarmschleimhaut ; Diabetes mellitus ; Biochemie ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Hyperlipidämien sind ein häufiger Befund bei Diabetes mellitus. Da neben der Leber auch die Dünndarmmukosa endogene Lipoproteine synthetisiert, war es von Interesse, bei 11 Erwachsenen mit juvenilem Diabetes und bei 7 Patienten mit Altersdiabetes den Lipidgehalt der Dünndarmmukosa zu bestimmen. Als Kontrolle dienten 11 nicht diabetische Patienten. Nach einer Nüchternperiode von 12–14 h erfolgte zunächst eine Blutabnahme zur Bestimmung von Nüchternblutzucker, Serumlipiden und glykosyliertem Hämoglobin AI, daraufhin wurden mittels einer hydraulischen Biopsiesonde oder endoskopisch mehrere Dünndarmbiopsien entnommen und zur biochemischen, histochemischen und elektronenoptischen Auswertung entsprechend aufgearbeitet. Biochemisch unterschieden sich die Patienten mit juvenilem und mit Altersdiabetes weder hinsichtlich der Serumlipidwerte noch der intestinalen Lipidkonzentrationen von den Kontrollpersonen. Auffallend war allerdings, daß Patienten mit Altersdiabetes eine signifikant höhere intestinale Triglyzeridkonzentration aufwiesen, als Patienten mit juvenilem Diabetes (p〈0,005). Nüchternblutzucker und Hämoglobin AI waren bei beiden Patientengruppen mäßig erhöht. Histochemisch waren sowohl bei den Patienten als auch bei den Kontrollpersonen Lipidpartikel in der Mukosa nachweisbar, allerdings mit großen individuellen Unterschieden. Elektronenoptisch unterschieden sich die Patienten mit Altersdiabetes nicht von den Kontrollen. Nur einer der Patienten mit juvenilem Diabetes zeigte gehäufte Lipidpartikel in den Zisternen des Golgi-Apparates. Somit konnte weder biochemisch, histochemisch, noch elektronenoptisch eine abnorme Lipidakkumulation in der Dünndarmschleimhaut von Patienten mit gut kontrolliertem Diabetes mellitus festgestellt werden.
    Notes: Summary Hyperlipemia is a frequent finding in diabetes mellitus. As not only the liver, but intestinal mucosa as well synthesizes endogenous lipoproteins, we have investigated the small intestinal mucosal lipid content in 11 adult patients with juvenile onset diabetes and in 7 patients with maturity onset diabetes. Eleven non-diabetic patients served as controls. After a fasting period of 12–14 h blood was drawn for determination of glucose, lipids and glycosylated hemoglobin AI. Then several small bowel biopsies were performed by an hydraulic multiple biopsy tube or endoscopically and the specimens were processed immediately for further biochemical, histochemical and electronmicroscopical workup. Patients with juvenile and with maturity onset diabetes did not differ from controls with regard to serum lipids and to intestinal mucosal lipids determined biochemically. Surprisingly, patients with maturity onset diabetes exhibited a significantly (p〈0,005) higher concentration of intestinal mucosal triglycerides than patients with juvenile onset diabetes. Fasting blood glucose and hemoglobin AI levels were slightly elevated in both groups of diabetic patients. Histochemically lipid particles were demonstrable in intestinal mucosa of diabetics and of controls with equal variability. The electronmicroscopical appearance of intestinal mucosa did not differ between diabetic patients and controls. Only in one patient with juvenile onset diabetes an accumulation of lipid particles within the cisternae of the Golgi apparatus was observed. In conclusion, neither biochemically, nor histochemically, nor electronmicroscopically an abnormal accumulation of lipids could be found in the small intestinal mucosa of patients with well controlled diabetes mellitus.
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    Experimental brain research 42 (1981), S. 362-370 
    ISSN: 1432-1106
    Keywords: Carotid baroreceptor ; Pain afferents ; Pontine neurone ; Rat ; Supraoptic nucleus neurone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Effects of pressure stimulation of the isolated carotid sinus, of occlusion of the common carotid artery and of tail pinching on the discharge activity of dorsal pontine area neurones and antidromically identified supraoptic neurosecretory neurones were studied in male rats anaesthetized with urethane. Electrical stimulation of the supraoptic nucleus (SON) produced antidromically conducted action potentials in a small number (24/384) of the units recorded in the dorsal pontine area. Pressure pulse stimulation of the isolated carotid sinus inhibited and carotid occlusion facilitated discharge activity in some of the tested dorsal pontine area neurones. In these responsive pontine neurones a transient excitation of grouped discharges was occasionally observed to concur with a small, spontaneous depression of the arterial blood pressure. Tail pinching excited some of these pontine neurones. Histological examination revealed that these responsive neurones were located in the dorsal pontine area close, but ventral and lateral, to the locus coeruleus. Electrical stimulation of the dorsal pons evoked a synaptically mediated excitation in 20 and inhibition in the other seven of the 52 SON units which were identified antidromically after stimulation of the pituitary stalk. Pressure stimulation of the isolated carotid sinus evoked an inhibition of discharge activity in some of the SON units which were excited by dorsal pontine area stimulation. All of the six tested units which showed inhibition after dorsal pontine area stimulation were unresponsive to pressure stimulation. Based on these data, it was concluded that at least some of the neurones which mediate carotid baroreceptor inputs to SON neurosecretory neurones are located in the dorsal pontine area close, but ventral and lateral, to the locus coeruleus and that these dorsal pontine area neurones also mediate converging synaptic inputs originating from somatic pain receptors.
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  • 34
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    Experimental brain research 42 (1981), S. 467-474 
    ISSN: 1432-1106
    Keywords: Interocular transfer ; Rat ; Commissures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of sectioning the corpus callosum on interocular transfer of a brightness and a horizontal/vertical discrimination was examined in hooded rats. Lesions of the posterior portion of the callosum usually led to moderate transfer deficits, but considerable individual variation was found. Lesions involving only the anterior part of the callosum had little effect on transfer. This suggests a functional localisation in the corpus callosum of the rat similar to that seen in higher mammals. Section of the posterior and tectal commissures and the thalamic massa intermedia in addition to the callosum had no greater effect on transfer than callosal section alone. It is therefore unlikely that these structures play a crucial role in interocular transfer in the rat.
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  • 35
    ISSN: 1432-0827
    Keywords: Rat ; Incisor ; Amelogenesis ; Acid phosphatase ; Ferritin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Acid phosphatase was localized in rat incisor ameloblasts without prior decalcification. Whenβ-glycerophosphate was used as the substrate, an intense reaction was observed in the supranuclear region of the secretory ameloblasts. But the reaction was dramatically reduced at the transitional stage and was very weak in the maturation ameloblasts. Whenp-nitrophenylphosphate was the substrate, the reaction product was consistently seen in the Golgi cisternae and the vesicular components of the ameloblasts at all stages of enamel development. These observations suggest that there are two acid phosphatases in ameloblasts. One is in the secretory ameloblasts and the other in the transition and maturation ameloblasts. X-ray micro-analyses for Fe and Pb showed that Fe and acid phosphatase were in the ferritin-containing vesicles at the later stage of enamel maturation. This evidence suggests that ferritin is digested in these vesicles for the release of the Fe pigment to the enamel. An increase in the number of intercellular bridges between ameloblasts was correlated with the dramatic decrease in height of ameloblasts at the pigment release stage. The ameloblast membranes were acid phosphatase positive at the intercellular bridges whenp-nitrophenylphosphate was the substrate. This activity may be involved in the reduction in the surface area of the ameloblast membranes.
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  • 36
    ISSN: 1432-0827
    Keywords: Connective Tissue ; Vitamin D deficiency ; Hydroxyproline excretion ; Glycosaminoglycan excretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The urinary excretion of two connective tissue metabolites was studied in both control and vitamin D deficient rats. Hydroxyproline (HyPRO) excretion was determined after 2, 13 and 22 months (experiment I). It decreased with aging in animals receiving the control diet. On the contrary, this excretion increased as a function of age in vitamin D deficient animals. At the age of 22 months, HyPRO excretion was respectively 31 and 1708 µg a day in control and deficient animals. HyPRO and glycosaminoglycans (GAG) excretion was measured on a group of both control and vitamin D deficient rats at the age of 21 months (experiment II). These results confirm the high excretion of HyPRO in deficient animals. On the contrary, the GAG excretion was higher in control animals than in deficient ones, the mean excretion being respectively 412 and 234 µg a day.
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  • 37
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    Calcified tissue international 33 (1981), S. 223-231 
    ISSN: 1432-0827
    Keywords: Protein deficiency ; Bone formation ; Skeletal development ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Protein deficiency was produced by freely feeding young rats a 1% lactalbumin diet for 12 weeks in order to study the effects of protein-calorie malnutrition on skeletal development. During the experiment the food and caloric intake and weight of the experimental animals decreased, while those parameters of the control animals progressively increased. However, when gross caloric intake was expressed as a function of the metabolic size of the animal, the caloric consumption was similar for both groups of animals. The protein-deficient animals exhibited micro-radiographic and histological features of an abnormal pattern of endochondral bone formation. Appositional bone growth, as determined by the daily appositional rate and the percentage of endosteal surfaces undergoing active bone formation, was significantly decreased in these animals, as was the percentage of periosteal surfaces exhibiting resorption. Both chemical analyses of the whole bone and electron probe microanalysis in the specific area of actively calcifying bone revealed no significant differences between the mineral content of control and protein-deficient animals. This study distinguishes the effects of protein deficiency from that of combined protein-calorie deprivation and demonstrates that the abnormal skeletal development observed was the result of a decrease in the quantity of bone formed rather than an altered mineral content.
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  • 38
    ISSN: 1432-0738
    Keywords: Methylmercury ; Neurotoxicity ; Sex difference ; Rat ; Cerebellar damage ; Coordination disorders
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Male and female rats were dosed daily by gastric gavage four or five times with 8.0 mg/kg Hg as methylmercury. Treatment lowered the body weight in relation to the body weight of untreated rats to the same extent in male and female rats but when body weight was related to the initial body weight, the effect of methylmercury was more pronounced in females than in males. The importance of differences in growth or loss of body weight is that in spite of the similar whole body clearance mercury concentrations were higher in females than in males. After identical doses the brains of females always contained more mercury than those of males and in both sexes the brain concentration of mercury showed a disproportionate elevation when the number of doses was increased from four to five. However, weight change alone does not explain the sex related difference in the brain concentration of mercury as this was evident even 72 h after a single dose. In agreement with the brain concentration of mercury, female rats developed more intensive co-ordination disorders and after five doses they had more extensive damage in the granular layer of the cerebellum than males.
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  • 39
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    Archives of toxicology 49 (1981), S. 85-91 
    ISSN: 1432-0738
    Keywords: Rabbits ; Lead acetate ; Ultrastructure ; Kidney ; Proximal tubule
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Electron microscopical studies were carried out on the kidneys of rabbits given s.c. injections of 0 (control), 0.25 or 0.50 mg lead acetate/kg b.w. 3 times a week during 14 weeks. At the end of the experimental period the animals had lead blood levels of 60, 500 and 600 μg/1 whole blood respectively. Treatment-related renal changes were found in the proximal tubules; they consisted of a dose-related increase in the amount of lysosomes in epithelial cells of the convoluted part, and of severely damaged cells and loss of brush border in the straight part. There was also an increase in lysosomal tubular inclusions, which are considered characteristic of lysosomes of the proximal tubular cells of the rabbit kidney. The significance of these findings for assessing the risk of occupational exposure to lead is briefly discussed.
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  • 40
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    Archives of toxicology 48 (1981), S. 29-39 
    ISSN: 1432-0738
    Keywords: Copper ; Zinc ; Mercury ; Diethyldithiocarbamate ; Carbon disulphide ; Thiocarbamates ; Chelating agent ; Mouse ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Oral treatment of rats with tetramethylthiuram disulphide (TMTDS), 0.1% mixed in the food (corresponding to 20–30 μmol daily) for one week, increased the brain levels of endogenous copper and zinc to 120% and 170%, respectively, of the control levels. Mice injected with HgCl2 (2.5 μmol/kg) were used to study further the effect of DDC (diethyldithiocarbamate), disulfiram, TMTDS or CS2 on heavy metal distribution. The brain levels of Hg were significantly increased in mice given DDC or TMTDS. Disulfiram and CS2 increased the brain levels marginally. Pregnant rats exposed to HgCl2 (0.5 μmol/kg) were also included in the studies. Treatment with DDC (0.5 mmol/kg) immediately after the mercury injection, increased the maternal brain concentration of mercury considerably, as measured after 24 and 78 h. The kidney levels were also increased. In the foetuses, the brain and liver levels were transiently increased after treatment with diethyldithiocarbamate. The observations support the hypothesis that the neurotoxicity of diethyldithiocarbamate and other thiocarbamates may be related to changes in heavy metal metabolism.
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  • 41
    ISSN: 1432-0738
    Keywords: Behavior ; Neurochemicals ; Manganese ; Lead ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Groups of rats were exposed simultaneously to manganese chloride (3 mg Mn2+/ml water) through drinking water and lead acetate intraperitoneally at dosages of 5.0, 8.0 and 12.0 mg Pb2+/kg daily for a period of 14 days. The magnitude of changes in the behavioral pattern, contents of biogenic amines and accumulation of lead in the brain of rats simultaneously exposed to the two metals was significantly greater than observed in rats after exposure to either of the metals alone. A definite dose-response relationship was, however, noticed only with the changes in the motoractivity, norepinephrine, 5-hydroxytryptamine levels and in the accumulation of lead in rats simultaneously exposed to manganese and lead. The lowering in the contents of norepinephrine after combined treatment was found to be related with the decrease in the motoractivity in the rats. The exact role of depression in the levels of dopamine and 5-hydroxytryptamine in inducing marked impairment in learning ability and increased aggressive behavior in rats after the combined exposure to manganese and lead could not be ascertained. The overall analysis of the data indicated that the simultaneous exposure to manganese and lead, particularly with highest dose of the latter, may produce serious derangements in the behavioral pattern and levels of biogenic amines in the brain of rats.
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  • 42
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    Anatomy and embryology 163 (1981), S. 43-53 
    ISSN: 1432-0568
    Keywords: Porcine placenta ; Areolae ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the areolae in the porcine placenta is described. The areolae occur on day 30 of pregnancy as a dome-shaped formation over the openings of the uterine glands. The lumen of the areolae is filled with the secretions of the uterine glands, the so-called histiotroph. The areolae lining epithelium is high collumnar, possesing long microvilli, a well-developed apical tubular system and numerous coated vesicles. This indicates that the epithelium has a high absorptive capacity. Our histochemical investigations reveal a high content of glycoproteins within the areolar lumen. The importance of one of the glycoprotein components of the histiotroph, uteroferrin, is discussed in connection with iron transfer from mother to the fetus.
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  • 43
    ISSN: 1432-0568
    Keywords: Silver staining ; Neurons ; Nucleolus ; Supraoptic nucleus ; Hypothalamus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The present paper describes a simple, efficient method for silver impregnation of supraoptic nuclei of the rat hypothalamus using a modification of the ammoniacal silver technique of Cajal (1903). This procedure, involving a silver-developer sequence in tissue blocks prior to plastic embedding, permits the simultaneous study of Ag-impregnated supraoptic neurons at both light and electron microscopic levels. Visualization of secretory magnocellular neurons impregnated by this technique using the electron microscope reveals a good preservation of nuclear structures. A selective accumulation of silver grains was observed over heterochromatin clumps and nucleoli, which allows the identification of the nucleolar fibrillar centers and also the dense fibrillar component as the main areas involved in the silver reaction. The meaning of such a silver-distribution pattern is discussed in the light of recent ultrastructural and biochemical data.
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  • 44
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    Archives of dermatological research 271 (1981), S. 55-61 
    ISSN: 1432-069X
    Keywords: Spontaneously regressing plane warts ; Activated Langerhans cells ; Unusual Langerhans cell granule ; Ultrastructure ; Spontan zurückgehende Plattenwarze ; Aktivierte Langerhanssche Zellen ; Ungewöhnliche Körner der Langerhansschen Zellen ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurden die ultrastrukturellen Veränderungen der Langerhansschen Zellen während der spontanen Involution der Plattenwarze untersucht. In den Gebieten mit aktivierten Makrophagen und epidermischen Zellen zeigten die Langerhansschen Zellen, wie in der Kontaktdermatitis, ein Zeichen erhöhter cellulärer Aktivität mit Vermehrung der cellulären Körner. Ungewöhnlich an der feinen Struktur der Körner der Langerhansschen Zellen war, daß der vesiculäre Teil innen mit einer Membrane umgeben wurde und daß dieser Teil häufig in Gestalt einer Schlinge vorkam.
    Notes: Summary Ultrastructural changes of Langerhans cells during spontaneous involution of plane warts were examined. In areas with activated macrophages and epidermal cell interaction, Langerhans cells showed signs of enhanced cellular activity with an increased number of Langerhans cell granules, as in contact dermatitis. The fine structure of Langerhans cell granules, however, was unusual in that the vesicular portion was surrounded internally by a membrane, and this portion frequently occurred independently taking the shape of a loop.
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  • 45
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    Archives of dermatological research 271 (1981), S. 91-99 
    ISSN: 1432-069X
    Keywords: Cutaneous angioleiomyoma ; Ultrastructure ; Weibel-Palade bodies ; Angioleiomyoma and glomus tumor ; Cutanes Angioleiomyon ; Ultrastruktur ; Weibel-Palade-Körperchen ; Angioleiomyom und Glomustumor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die elektronenmikroskopische Untersuchung eines cutanen Angioleiomyoms zeigte, daß die Muskelumhüllungen der Blutgefäße aus typischen glatten Muskelzellen aufgebaut sind. Die Zentralgefäße haben die ultrastrukturellen Charakteristika kleiner Venulen und zeigen neben einem hohen Endothel große Mengen von Weibel-Palade-Körperchen. Abgesehen von sehr spärlichen marklosen Nervenfasern, die kleine Arteriolen begleiten, finden sich keine bedeutenderen nervalen Strukturen. Aufgrund der gravierenden ultrastrukturellen Unterschiede kann eine nähere Beziehung zwischen Angioleiomyom und Glomustumor ausgeschlossen werden.
    Notes: Summary Electron-microscopic examination of a cutaneous angioleiomyoma demonstrated that the muscular coat enveloping the blood vessels is formed of typical smooth muscle cells. The central vessels exhibit the ultrastructural features of small venules with a prominent endothelium and large numbers of Weibel-Palade bodies. Except for scanty unmyelinated nerve fibers accompanying small arterioles, no significant nerval structures were encountered. In view of the evident ultrastructural differences, a relationship of angioleiomyoma and glomus tumor can be ruled out.
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  • 46
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    Anatomy and embryology 162 (1981), S. 403-417 
    ISSN: 1432-0568
    Keywords: Muscle ; Ultrastructure ; Differentiation ; Growth and development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The differentiation of skeletal muscle was studied by electron microscopy in bovine fetuses from 47 days gestation to neonatal calves 3 days of age. Initally, the muscle was composed of clusters of myotubes with mononucleated myoblasts between them. In 2-month-old fetuses these myoblasts became apposed to the differentiating muscle cells and were enclosed within the rudimentary basal lamina of the myotubes. At this stage the clusters of myotubes consisted of central, larger diameter, more differentiated myotubes and also the mononucleated satellite cells. The differentiated myotubes separated from the clusters accompanied by satellite cells which continued proliferating and fused together to form new generations of satellite myotubes. In this manner new clusters of myotubes were formed. By 4–5 months some of the separating myotubes began to form individual myotubes and independent myofibers were prominent in fetuses of 5–8 months of age. The myofibers in the 8-month-old fetuses showed diversification into fiber types by differences in the thickness of the Z-line, the prominence of the sarcotubular system, the amount of glycogen and lipid droplets and also the number of mitochondria.
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  • 47
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    Anatomy and embryology 162 (1981), S. 489-492 
    ISSN: 1432-0568
    Keywords: Visual cortex ; 6-hydroxydopamine ; Development ; Morphology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The development of the visual cortex was examined in control rats and in littermates whose cortical noradrenergic innervation was removed with 6-hydroxydopamine. Qualitative and quantitative observations revealed no differences in the lamination, cytoarchitecture, cell density and size between the two groups of animals. These results suggest that the number, size, and distribution of cortical neurons are not significantly altered in the absence of noradrenergic afferents.
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  • 48
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    Keywords: Thalamus ; Ultrastructure ; Cat ; Quantitative analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the ventrobasal complex (VB) of the cat thalamus was investigated in order to compare the data with those obtained in other thalamic nuclei. New data are described regarding the identification of Golgi II type neurons and several forms of axo-somatic synapses. By means of a quantitative analysis the number of different profiles, distribution of interprofile contacts, synaptic densities and degree of synaptic input of the two main cell-types were defined. The quantitative data obtained in the VB complex were compared with values for the lateral geniculate body (CGL), nucleus anterior ventralis (AV-non-sensory relay thalamic nucleus) and nucleus lateralis posterior-pulvinar complex (LP-PU-associative thalamic nucleus). The quantitative data reveal that: 1. The occurrence of RL terminals is equal in the two relay nuclei (VB and AV) and three-fold higher than in the LP-PU. 2. The percentage ratio of specific terminals (RL) in the total surface area in the relay nuclei is three-fold higher than in the LP-PU. 3. The RL→D synapses are twice as numerous in the relay nuclei as in the associative nucleus. 4. The density of synaptic RS profiles in VB is half of that found in LP-Pu. 5. In the thalamic relay nuclei the number of synaptic contacts on Golgi II type neurons is one-third of the synaptic supply of relay neurons; in the LP-Pu the amount of synaptic contacts on Golgi II type neuron approaches the synaptic supply of projective neurons.
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  • 49
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    Anatomy and embryology 163 (1981), S. 215-222 
    ISSN: 1432-0568
    Keywords: Rat uterus ; Epithelium ; Ultrastructure ; Decidualization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Unilateral decidualization was induced in uteri of ovariectomized hormone-injected prepubertal and young adult rats. The antimesometrial luminal epithelia of both the decidualized and contralateral hormone-primed (non-decidual) control uteri were examined and compared by transmission and scanning electron microscopy. Epithelial cells of control uteri were columnar and they had many short microvilli on their luminal surfaces. Nuclei of these cells were round or oval and euchromatic, and other organelles were intact. In decidualized uteri luminal epithelial cells were flat and attenuated, were of greater average widths and possessed fewer microvilli. Some evidence of the degenerative changes which normally follow maximal decidual development in this region of the uterus could be seen within the flattened epithelial cells. The degenerative alterations were nuclear and cytoplasmic. Increase in lipid was observed in epithelial cells of decidualized uteri. This accumulation of intracellular lipid probably resulted from ingestion by the epithelial cells of intraluminally injected sesame oil, according to the protocol for stimulating decidualization.
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  • 50
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    Anatomy and embryology 163 (1981), S. 71-75 
    ISSN: 1432-0568
    Keywords: Visual cortex ; Development ; Projections ; Layer I ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The development of the thalamic afferent projections to layer I of the visual cortex of the albino rat was studied using the retrograde transport of horseradish peroxidase. The results show that the projections to layer I which arise in the “nonspecific” thalamic nuclei (lateral posterior nucleus, posterior complex and ventromedial nucleus) develop earlier than the projection from the “specific” nucleus (dorsal lateral geniculate nucleus).
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  • 51
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    Anatomy and embryology 161 (1981), S. 419-431 
    ISSN: 1432-0568
    Keywords: Nuclei habenulae ; Biomathematical Analysis ; Fresh Volume ; Rat ; Spontaneous Nerve Cell Degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The growth of the nuclei habenulae medialis et lateralis of albino rats is described by monotonically increasing growth curves of fresh volumes during ontogenesis. The nucleus habenulae medialis matures earlier than the nucleus habenulae lateralis in the perinatal period. However, the two nuclei reach their final volume at about the same time. Simultaneous electron microscopic investigation reveals the phenomenon of spontaneous nerve cell degeneration within the nuclei habenulae during ontogenesis in spite of the non-overshooting growth curves for the habenular nuclei.
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  • 52
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    Anatomy and embryology 161 (1981), S. 329-340 
    ISSN: 1432-0568
    Keywords: Aortic valve ; Smooth muscle cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The location and the spatial arrangement of smooth muscle cells in aortic valves have been assessed by a systematic analysis of serial semithin sections of plastic embedded porcine and human aortic leaflets, combined with an electron microscope study. The investigation showed that smooth muscle cells, either single and arranged in thin bundles, and other cell types such as myofibroblasts are constantly present in the aortic valve leaflets. In addition, it was possible to devise a model of the three dimensional, specific organization of the smooth muscle bundles which can be interpreted as an intrinsic muscle system of the leaflets. As the muscular elements might play an active role in the normal functioning of the valve, their presence should be taken into account in designing (bio) prosthetic leaflets and in the evaluation of valve pathology.
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  • 53
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    Acta neuropathologica 53 (1981), S. 41-50 
    ISSN: 1432-0533
    Keywords: Giant axon swellings ; Rat ; Drug-induced lipidosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This study is concerned with the structure and topographic distribution of axonal alterations in the area postrema and in several adjacent nuclei of adult rats treated with different lipidosis-inducing drugs. The effects of three compounds (chloroquine, quinacrine, perhexiline) that seem to be largely excluded from most parts of the brain except circumventricular organs were compared with a reference compound (chlorphentermine) that has general access to the brain of adult rats. Only chlorphentermine caused generalized axonal alterations (intra-axonal accumulation of polymorphous osmiophilic materials, giant axonal swellings) in all inspected nuclei (area postrema, nucleus gracilis, nucleus tractus solitarii, nucleus nervi hypoglossi, nucleus dorsalis nervi vagi), with nucleus gracilis possessing the most vulnerable axons and axon terminals. The axonal effects of chloroquine were severe only in area postrema and in the closely adjacent neuropil of nucleus gracilis and nucleus tractus solitarii, whereas in the remaining regions axonal alterations were either moderate (lateral portions of nucleus gracilis) or absent. Axonal effects of quinacrine and perhexiline were confined to area postrema. The findings suggest that the topography of the severe axon alterations is greatly dependent on drug distribution. It is concluded that two factors have generally to be considered as responsible for the giant axon swellings found after application of lipidosis-inducing drugs: (a) local drug action upon the axon itself, and (b) lysosomal overloading in the corresponding perikaryon, with factor (a) probably being more potent than factor (b).
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  • 54
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    Acta neuropathologica 53 (1981), S. 99-106 
    ISSN: 1432-0533
    Keywords: Peripheral nerve ; Rat ; Streptozotocin diabetes ; Morphometry ; Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary One year after beginning of the experiment seven streptozotocin-injected Wistar rats and seven controls were fixed by whole-body perfusion, the nervus radialis was dissected and processed for light and electron microscopy. After light-microscopic study standard photographs of nerve cross sections were measured by means of a semiautomatic image analyzer. The following measurements were obtained: (1) surface of fibers, axons, and myelin sheaths; (2) ratio of myelin to axon surface; and (3) percent of endoneural space. Group means and standard errors were calculated, and cumulated class distributions were made. Ultrathin sections from all animals considered morphometrically were studied qualitatively for ultrastructural changes. The quantitative study revealed in the diabetics reduction of average myelin surface, increase of endoneural space, and reduction of myelin/axon ratio. The main ultrastructural findings were lesions of Schwann and mesenchymal cells, followed by less frequent and less severe changes in axons and endothelium. These results suggest a primary Schwann cell lesion was responsible for the observed myelin reduction.
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  • 55
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    Acta neuropathologica 53 (1981), S. 267-273 
    ISSN: 1432-0533
    Keywords: Rat ; Neck muscles ; Motoneurons ; Dendrites ; HRP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The nuclei for the nerves of a dorsal (m. splenius) and a ventral (m. longus capitis) neck muscle of the rat were retrogradely labeled by applying horseradish peroxidase (HRP) to the respective cut muscle nerves. Motoneurons of both muscles were analyzed for their localization, diameter of perikarya, and area of dendritic arborization. The nucleus of m. longus capitis is situated dorsomedially, the nucleus of m. splenius ventromedially within the ventral horn. Thus, the relative positions of the two nuclei are inverse to those of their muscles, with the more ventral nucleus innervating the more dorsal muscle. In both nuclei the areas of dendritic arborization are very large, extending into the nuclei of other neck muscles, and also into the ipsilateral anterior funiculus. In addition, m. longus capitis motoneurons were found to send dendrites into the contralateral ventral horn, reaching the nucleus of the contralateral muscle. The size distribution of perikarya is bimodal for m. longus capitis motoneurons, but only unimodal in the case of m. splenius.
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  • 56
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    Keywords: Fetal alcohol syndrome ; Rat ; Liquid diet ; Cerebellum ; Purkinje cells ; Rough endoplasmic reticulum ; Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Alcohol was administed in a vitaminsupplemented liquid diet (Stardit) to Wistar rats 4 weeks before mating and during pregnancy. Of the daily calories 38–40% were supplied by alcohol and by isocaloric sucrose in the controls. Offspring of alcohol drinking dams showed a reduced birth weight and gained weight less rapidly than the controls. On day 3, 4, 7, 12, 17 and 21, experimental animals and controls were perfused for histological and electron microscopic investigations. Morphometric analysis of the cerebella (Fol. 5 and Fol. 8) showed no difference in the number of Purkinje cells. However, on day 7 the Purkinje cell nuclei of experimental pups were significantly smaller. This difference disappeared at day 12. Electron microscopic investigations in the 4, 7, and 12 days old experimental animals revealed a delayed cytoplasmic maturation of Purkinje cells which mainly involved the rough endoplasmic reticulum. At 17 days, there was no difference between the two groups. These data are discussed in relation to alcohol-induced metabolic changes in the brain.
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  • 57
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    Acta neuropathologica 54 (1981), S. 113-119 
    ISSN: 1432-0533
    Keywords: Multisystem atrophy ; Neuronal intranuclear ; Hyaline inclusions ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An 18-year-old girl died following a slowly progressive neurodegenerative disease of nine years duration. At 9 years of age, she developed intellectual deterioration associated with speach difficulty, pseudobulbar palsy and ataxia. The progression included spastic quadriplegia, anarthria, severe dysphagia, ophthalmoplegia, and pes cavus. There was no family history. The brain was uniformly small and the substantia nigra was not pigmented. Neuronal loss and gliosis involving globus pallidus, subthalamic nucleus, thalamic nuclei, brain stem, cerebellum, and spinal cord gave the picture of multisystem atrophy. Intranuclear hyaline inclusions were observed in numerous neurons of the central and peripheral nervous system. These were auto-fluorescent and were made up of intermingled straight filaments (8–9 nm in diameter). Only two previously reported cases showing these same inclusions are known. They are reviewed, compared, and discussed in relation to primary neuronal degenerations.
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  • 58
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    Acta neuropathologica 54 (1981), S. 121-127 
    ISSN: 1432-0533
    Keywords: Rat ; Protein deprivation ; Nerve fibre degeneration ; Central nervous system ; Peripheral nervous system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Knowledge from previous reports that kwashiorkor in man may lead to nerve fibre degeneration prompted this study on rats. The rats were subjected to severe protein deprivation from 6 weeks of age. Protein deprivation was achieved by feeding the rats ad lib with a diet containing only 1.5% protein. Control rats received an iso-caloric diet with 14% protein. The vitamin content in both diets was well above normal requirements. In relation to body weight the protein-deprived rats did not consume less food than the control rats. Protein deprivation resulted in stunted body growth, markedly reduced values of serum albumin, and changes in the fur accompanied by areas of alopecia. Furthermore, the protein-deprived rats showed degeneration of nerve fibres in the medial parts of the posterior columns of the cervical but not the sacral part of the spinal cord and nerve fibre degeneration in the distal but not the proximal parts of the longitudinal tail nerves. Teased nerve fibre preparations of the tail nerves revealed changes consistent with the Wallerian type of degeneration. It is concluded that severe protein deprivation in young rats may lead to a “dying-back” type of neuropathy in the central and peripheral nervous systems.
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  • 59
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    Acta neuropathologica 54 (1981), S. 135-142 
    ISSN: 1432-0533
    Keywords: Cultured Schwann cells ; Ultrastructure ; Cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Schwann cell cultures were established from sciatic nerve of 3 day-old rats. Described are the ultrastructural, histochemical and ultracytochemical properties of amyelic cultured rat Schwann cells. Ultrastructural characteristics of the cultured Schwann cells are compared to the Schwann cells of 3 day-old and adult rat sciatic nerve. These findings serve as a basis for comparison when studying experimentally induced alterations in the cultured Schwann cells as well as changes due to myelination in vitro.
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    Acta neuropathologica 54 (1981), S. 129-134 
    ISSN: 1432-0533
    Keywords: Peripheral nerve ; Rat ; Streptozotocin diabetes ; Morphometry ; Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Eight streptozotocin-injected Wistar rats and eight controls were fixed by whole-body perfusion 4 months after beginning of the experiment, the nervus radialis was dissected and processed for light and electron microscopy. After light-microscopic study standard photographs of nerve cross sections were measured by means of a semiautomatic image analyzer. The following measurements were obtained: (1) surface of fibres, axons, and myelin sheaths, (2) ratio of myelin to axon surface, and (3) percent of endoneural space. Group means and standard deviations were calculated, and cumulated size class distributions were made. Representative nerve specimens from all animals were also studied by electron microscopy. The quantitative study revealed in the diabetics a severe reduction of the average myelin surface, a mild increase of axonal cross section and of endoneural space, a reduction of myelin/axon ratio and a mild reduction in cross section of the nerve. Ultrastructural lesions of minor degree were found in the cytoplasm of Schwann and mesenchymal cells, no lesion was observed in axons. These findings demonstrate the presence of neuropathy 4 months after induction of diabetes and support the pathogenetic role of the Schwann cell in our experimental model.
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  • 61
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    Acta neuropathologica 54 (1981), S. 199-202 
    ISSN: 1432-0533
    Keywords: Hereditary sensory neuropathy ; Sweat glands ; Unmyelinated axons ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructural study of a skin biopsy in a patient afflicted with hereditary sensory neuropathy type IV (congenital insensitivity to pain with anhidrosis) did not reveal any unmyelinated axons or axonal terminals around eccrine sweat glands but only proccsses, partially covered by a basement membrane and therefore resembling Schwann cell processes. The absence of such unmyelinated axons in close proximity to eccrine sweat glands where they normally occur appears to be the morphological equivalent to the anhidrosis and also corresponds to the deficiency of unmyelinated axons in the sural nerve of the same patient, as previously reported.
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  • 62
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    Acta neuropathologica 54 (1981), S. 239-246 
    ISSN: 1432-0533
    Keywords: Alzheimer's disease ; Neurofibrillary Tangles ; Senile dementia ; Supranuclear palsy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Alzheimer's neurofibrillary tangles were studied by electron microscopy. The study includes four cases of Alzheimer's disease, two cases of atypical senile dementia, and one case of progressive supranuclear palsy. In Alzheimer's disease the tangles were composed of either straight filaments or paired helical filaments. In progressive supranuclear palsy the tangles were composed of 15 nm straight filaments or helical filaments. A few straight filaments were mixed with paired helical filaments. In atypical senile dementia, both straight and paired helical filaments comprised the tangles and one type of filaments appeared to intermingle with the other in the same neurons.
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  • 63
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    Keywords: Human rabies ; Negri bodies ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Light-and electron-microscopical studies were conducted on necropsy material from six cases of rabies encephalitis including three with the unusual feature of surviving for over 14 days as a result of intensive medical care. This included administration of antiviral agents and interferon inducers and prevention of hypoxia by intermittent positive pressure ventilation. In all these cases, typical Negri bodies were demonstrated. Inflammatory reaction was absent or minimal. Unlike the cases with short survival where Negri bodies were infrequently seen and restricted mostly to the hippocampus, in cases with prolonged survival, they were present in large number, widely distributed throughout the grey matter of the brain. The associated inflammatory reaction in these cases, however, did not keep pace with the increase in number of inclusion bodies. Peripheral neuritis was observed in two of these cases, which also showed myelitis involving the cervical region and inflammation of dorsal root ganglia. One of them showed necrosis and severe inflammation of the lower cervical sympathetic ganglion. An electron-microscopical study conducted in four cases showed three forms of the inclusion body in the cytoplasm of neurons.
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  • 64
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    Acta neuropathologica 54 (1981), S. 315-320 
    ISSN: 1432-0533
    Keywords: Myogenesis ; Neoplasms ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of myogenic cells occurring in neoplasms was investigated and aspects of differentiation (myofilament interactions and organization, and sarcotubular development) were characterized. The stages of muscle differentiation present were extremely similar to those reported during human fetal development prior to innervation. Exceptions, however, being: (1) the presence of fewer multinucleated cells; (2) the general lack of cell elongation and its apparent effect on myofibril orientation; and (3) evidence of a higher number of myofilaments in mononucleated cells. The findings were compared to those reported in normal human fetal development, human myogenic cells in vitro and the literature on mammalian and avian muscle development and discussed with regard to the influence of tension and innervation. The significance of degenerating myogenic cells found in these neoplasms is also discussed.
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  • 65
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    Acta neuropathologica 54 (1981), S. 321-324 
    ISSN: 1432-0533
    Keywords: Choroid plexus papilloma (CPP) ; Malignant DCPP ; Choroid plexus endothelium ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A disseminated choroid plexus papilloma (DCPP) with a malignant change in the cervico-spinal leptomeninges observed 4 years after the removal of choroid plexus papilloma (CPP), originating from the fourth ventricle, was studied under the electron microscope. Although the ultrastructure of intracranial CPP has been reported by several authors, there are just a few reports on DCPP. The present tumor was ultrastructurally very similar to normal choroid plexus, but the lack of the capillary fenestration and of invaginations of the epithelial basal plasmalemmas suggested that the epithelium was deprived of secretory function.
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  • 66
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    Acta neuropathologica 54 (1981), S. 329-330 
    ISSN: 1432-0533
    Keywords: Muscular dystrophy, Duchenne type ; Ultrastructure ; Satellite cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A new organelle found in a case of Duchenne muscular dystrophy is described. It was located at the periphery of a regenerated myofibre close to a satellite cell. It was roughly sperical in shape and 0.30–0.35 μm in diameter. Its internal structure was examined in serial and tilted sections, and consisted of parallel arrays of laminae or, possibly, filaments. The nature of the organelle is briefly discussed.
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  • 67
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    Keywords: Phrenic nerve ; Diaphragm muscle ; Rat ; Streptozotocin diabetes ; Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary One year after beginning of the experiment six streptozotocin-injected Wistar rats and six controls were anesthetized and fixed by whole-body perfusion. The diaphragms were isolated and processed for light and electron microscopy. Both the intramuscular branches of the phrenic nerve and the muscle fibers were studied morphologically and morphometrically. Moreover, two diabetic and two control rats were killed by decapitation, the diaphragms were deep-frozen and studied histochemically for myofibrillar ATP-ase. A significant reduction of fiber cross section surface, due to reduction of both myelin and axon surfaces, was found in the phrenic nerves of diabetics. Lesions of Schwann and mesenchymal endoneural cells were the main ultrastructural changes. The diaphragm was much thinner in diabetics than in controls. In diabetics the number of lipid droplets found in red muscle fibers was increased and the white muscle fibers were hypotrophic. These findings were confirmed by the morphometric study. Ultrastructurally, various types of lipid droplets, streaming of Z line, organelle degeneration, invagination of nuclear membrane, and increase in number of satellite cells were found in red fibers of diabetic animals. Disorientation of the triads was the most frequent lesion in white fibers of diabetics. These results demonstrate that both neuropathy and myopathy are present in functionally related nerve and muscle from rats after 12 months of streptozotocin-induced diabetes. Both the dysmetabolic condition and the nervous lesions may have contributed to the muscular changes.
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    Acta neuropathologica 55 (1981), S. 105-111 
    ISSN: 1432-0533
    Keywords: Brain tumor ; Brain edema ; Histology ; Cytology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In this study an experimental intracerebral tumor has been investigated with special consideration of structures, which may be involved in edema production and/or resolution. For this purpose a cloned tumor cell line (RG1 2.2) has been injected stereotactically into the brain of BD-IX rats. The tumor has some characteristics in common with low differentiated oligodendroglioma in men. A honcycomb architecture may be seen in the center of the tumor. It is built up by rounded or elongated cells, which can be impregnated in parts. In the central area, cells exhibit a volominous digestive apparatus, composed of dictyosomes, vesicles, and some vacuoles with a membranaceous or homogeneous content. Tumor cells in the periphery show large processes and a small digestive apparatus. The sinusoidal tumor vessels are composed of an endothelium with many vesicles but no openings.
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  • 69
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    Acta neuropathologica 55 (1981), S. 167-172 
    ISSN: 1432-0533
    Keywords: Myopathy ; Pathology ; Rat ; Steroid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The steroids triamcinolone, dexamethasone, beta-methasone, and cortisone were administered i.p. to adult rats for 14–63 days. The extensor digitorum longus (EDL, white muscle) and soleus (SOL, red muscle) muscles were examined histologically and histochemically. Triamcinolone was the most potent lesion-producing drug. Selective involvement of muscles, and of the fiber types within them was observed: Neerotic changes were seen only in the type 1 fibers of the SOL; atrophic fibers were observed in the type 2 fibers of both the SOL and the EDL.
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  • 70
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    Acta neuropathologica 55 (1981), S. 199-203 
    ISSN: 1432-0533
    Keywords: Meningioma ; “Pseudopsammoma bodies” ; Ultrastructure ; Intracytoplasmic lumina ; Hyaline inclusions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Seven cases of meningiomas with “pseudopsammoma bodies” have previously been described in the literature. Two additional cases are presented. Electron microscopy of the cells surrounding the “pseudopsammoma bodies” reveals an ultrastructure different from that of the meningotheliomatous cells. It is concluded that meningotheliomatous meningiomas with “pseudopsammoma bodies” are mixed tumours, including a non-meningotheliomatous component, the origin and significance of which is uncertain.
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  • 71
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    Acta neuropathologica 53 (1981), S. 333-336 
    ISSN: 1432-0533
    Keywords: Amacrine cell ; Tay-Sachs disease ; Ultrastructure ; Biochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural study of the retina from a patient with Tay-Sachs disease disclosed that amacrine cells as well as ganglion cells were loaded with numerous membranous cytoplasmic bodies, suggesting an accumulation of GM2 ganglioside, whereas the horizontal cells, bipolar cells, and photoreceptor cells were intact. Chromatography of lipids from the retina showed a prominent spot of GM2 ganglioside. These facts suggest that lipid metabolism in amacrine cells may be different from that in other retinal cells.
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  • 72
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    Calcified tissue international 33 (1981), S. 603-618 
    ISSN: 1432-0827
    Keywords: Preameloblasts ; Tooth germs ; Monkey ; Enamel ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Cytodifferentiation of inner enamel epithelium and the adjacent connective tissue from the tip of the cervical loop to the initiation of enamel elaboration in twoMacaca species was examined. Ten- to twelve-month-old specimens were fixed by perfusion and the permanent tooth buds were prepared for transmission electron microscopy. At the cervical loop proper, inner enamel epithelium cells have lobed nuclei, a paucity of cytoplasm, and wide extracellular spaces; the basal lamina facing the dental papilla is straight. With increasing distance from the tip of the cervical loop, the following changes occur gradually: (a) preameloblasts elongate from 15 to 45 µm, and their organelles, particularly mitochondria and profiles of rough endoplasmic reticulum, become more numerous; (b) extracellular spaces decrease between preameloblasts starting at the basal (infranuclear) end; (c) the basement membrane becomes convoluted and associated with aperiodic fibers; (d) preodontoblast projections penetrate the aperiodic fibers; (e) collagen fibers subjacent to the basement membrane increase in density, with particularly thick fibers paralleling the aperiodic fibers. These modifications occur within three-fourths of the distance from the tip of the cervical loop to the mineralization front. The condensation of preodontoblasts is followed immediately by predentin synthesis. Concomitantly, the basement membrane breaks down and the aperiodic fibers are engulfed by preameloblasts. Preameloblast projections penetrate junctional predentin, contact mineralized dentin, and enamel synthesis ensues. At this stage the ameloblast is 45 µm long, the nucleus is central or basal, the Golgi apparatus has migrated apically, but the Tomes' process has not yet formed. The results indicate that odontogenesis inMacaca monkeys more closely resembles human odontogenesis than does that in the murine rodents.
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  • 73
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    Archives of microbiology 128 (1981), S. 384-389 
    ISSN: 1432-072X
    Keywords: Didymium iridis ; Microcyst ; Excystment ; Germination ; Ultrastructure ; Mycetozoa ; Myxomycetes ; Myxamoeba
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Microcysts of the myxomycete Didymium iridis were induced to excyst by transfer to 5mM potassium phosphate buffer. After 1 h in suspension, 90% of the microcysts had germinated into myxamoebae distinguishable by phase contrast microscopy and staining with Lugol's iodine. Both pH and osmolarity affected the kinetics of excystment. The rate and extent of excystment were decreased by cycloheximide but remained unaffected by actinomycin D, suggesting a requirement for protein synthesis but not RNA synthesis. Initially, the outer wall layers separated from the inner layer, which gradually expanded and loosened. The protoplast rehydrated and reverted to a vegetative morphology. Excysting cells were characterized by nucleolar inclusions, changes in the nuclear envelope and plasma membrane, appearance of ringed cisternal elements and microbodies in the cytoplasm, and formation of a densely fibrous zone adjacent to the site of emergence. Excysting populations have been classified into characteristic stages: mature, initiated, swollen, and pre-emergent microcysts.
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  • 74
    ISSN: 1432-072X
    Keywords: Arthrobacter ; Facultative methylotroph ; Amine oxidase ; Catalase ; RuMP cycle of formaldehyde fixation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A facultative methylotrophic bacterium was isolated from enrichment cultures containing methylamine as the sole carbon source. It was tentatively identified as an Arthrobacter species. Extracts of cells grown on methylamine or ethylamine contained high levels of amine oxidase (E.C. 1.4.3.) activity. Glucose- or choline-grown cells lacked this enzyme. Oxidation of primary amines by the enzyme resulted in the formation of H2O2; as a consequence high levels of catalase were present in methylamine-and ethylamine-grown cells. The significance of catalase in vivo was demonstrated by addition of 20 mM aminotriazole (a catalase inhibitor) to exponentially growing cells. This completely blocked growth on methylamine whereas growth on glucose was hardly affected. Cytochemical studies showed that methylamine-dependent H2O2 production mainly occurred on invaginations of the cytoplasmic membrane. Assimilation of formaldehyde which is generated during methylamine oxidation was by the FBP variant of the RuMP cycle of formaldehyde fixation. The absence of NAD-dependent formaldehyde and formate dehydrogenases indicated the operation of a non-linear oxidation sequence for formal-dehyde via hexulose phosphate synthase. Enzyme profiles of the organism grown on various substrates suggested that the synthesis of amine oxidase, catalase and the enzymes of the RuMP cycle is not under coordinate control.
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  • 75
    ISSN: 1432-0738
    Keywords: Methylmercury ; Protein synthesis ; Liver ; Adrenal ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract (1) A single injection of methylmercury chloride in the rat (10–50 mg/kg) increased both in vivo and in vitro rates of 14C-leucine incorporation into the protein of the post-mitochondrial supernatant fraction of the liver. In contrast, no stimulation of protein synthesis was observed in the brain of the methylmercury-treated rats. (2) Methylmercury administration also stimulated RNA polymerase activities in isolated hepatic nuclei, stimulation of Mg-dependent activity being higher than that of Mn-dependent activity. (3) In experiments with adrenalectomized rats, it was found that the stimulatory effect of methylmercury on protein and RNA synthesis in the liver was mediated partly through the adrenal gland. (4) Analysis of serum by starch-block electrophoresis revealed that synthesis of all serum proteins, including albumin and α-γ globulin fractions, was stimulated by methylmercury treatment. (5) These results suggest that the observed effects of methylmercury on the liver depend on mechanisms other than enhancement of the synthesis of acute-phase proteins.
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  • 76
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    Archives of toxicology 47 (1981), S. 101-111 
    ISSN: 1432-0738
    Keywords: Cerebellar cortex ; Methylmercury ; Toxicity ; Rat ; Morphometry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A single dose of 10 mg methylmercury chloride per kg body weight was given to 30 days old rats and to adult rats (180–200 g). This resulted in brain levels of 1.4–2.2 μg Hg/g wet weight. In the young rats electron microscopic morphometry showed swelling of the granule cells. The extent of changes was more pronounced in the cerebellar hemispheres than in the vermais and flocculus. At 7 days after giving the methylmercury the granule cells appeared to have returned to normal. Methylmercury produced both light and electron microscopic changes in cerebellar neurons of adult (180–200 g) rats 3 days after dosing. 2.5–10% of the granule cells appeared dark and condensed in toluidine blue stained semithin sections of perfusion fixed and plastic embedded material. In control animals the comparable percentage never exceeded 1. By electron microscopic morphometry the dark cells proved to be shrunken to 70%, whereas the remaining light granule cells were swollen to 130% of the normal cell volume. The heterochromatin and mitochondrial volumes per cell remained constant in both dark and light cells from methylmercury treated animals. In the Purkinje cells from both young and adult rats, geometrical changes in the cisternae of the granulated endoplasmic reticulum were evident. The swelling and shrinkage of the granule cells is supposed to be due to impaired electrolyte control and the disorganized granulated endoplasmic reticulum of the Purkinje cells may be related to the deleterious effects on protein synthesis.
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  • 77
    ISSN: 1432-0738
    Keywords: CO exposure ; Cardiovascular system ; Rat ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Regarding the potential impact of traffic-born air pollutants on public health, in recent years attention has increasingly been focused on the possible effects on the cardiovascular system. In order to investigate this problem further, the influence of long-term exhaust gas exposure on rats has been studied. One hundred Wistar rats of either sex were exposed 5 × 8 h/week up to 28 months to an atmosphere polluted by the emissions of an idling Otto engine, CO concentrations held constant at 90 ppm. A second group (50 rats) was exposed to 250 ppm for 6 months. Blood parameters and body weight were controlled. Specimens of CNS, heart, vessels, kidney etc. were investigated light microscopically. Focal necroses of the myocardium with inflammatory reactions as well as interstitial fibrosis were found in the heart muscle of the 90 ppm group. In the 250 ppm group endothelial proliferations, edema of the intima and deposits of proteoglycanes in the media were observed. We conclude that subtoxic concentrations of CO which only lead to slight morphologic changes may aggravate preexisting lesions caused by high risk conditions, e.g., hypertension or hypercholesteremia.
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    Archives of toxicology 49 (1981), S. 1-13 
    ISSN: 1432-0738
    Keywords: Chlorinated paraffins ; Liver ; Rat ; Metabolism ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Short term effects of chlorinated paraffins with different length of the carbon chain and different degree of chlorination were investigated with respect to rat liver cytochrome P-450 mediated metabolism and liver cell morphology. When paraffins were administered by i.p. injection liver weights increased inversely with the length of the carbon chain. The short carbon chain paraffins with a high degree of chlorination increased the concentration of liver microsomal cytochrome P-450, inhibited the metabolism of 7-ethoxyresorufin but increased the metabolism of benzo(a)pyrene, especially the formation of the 4,5-diol metabolite. Short carbon chain paraffins gave rise to a proliferation of the smooth ER, increased the number of cytoplasmic fat droplets as well as the number and size of mitochondria and peroxisomes and finally induced the occurrence of autophagosomes and lysosomes. The fat droplets were preferentially degraded in lysosomes. In all respects the long carbon chain paraffins were less biologically active.
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    Archives of toxicology 47 (1981), S. 191-196 
    ISSN: 1432-0738
    Keywords: Manganese ; l-Dopa ; Dopamine ; Corpus striatum ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The turnover rate of striatal dopamine (DA) and the effect of l-dopa treatment was investigated in rats after the daily oral administration of MnCl2 · 4H2O for a period of 30 days. The turnover rate of striatal DA, as determined by the administration of α-methyl-p-tyrosine, increased significantly in manganese-exposed rats. l-Dopa administration resulted in a significant elevation in the levels of DA and its metabolite, homovanillic acid, in manganese-exposed rats, but these neurochemical changes could not be correlated with the concentration of manganese in the striatum. We therefore advise that l-dopa therapy should not be tried in early manganese intoxication, as it may aggravate manic symptoms due to marked increase in brain DA.
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    Archives of toxicology 47 (1981), S. 233-239 
    ISSN: 1432-0738
    Keywords: Hexachlorobenzene ; Paraffin ; Squalane ; Pendular perfusion ; Intestinal excretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract 1. The intestinal excretion of hexachlorobenzene (HCB) was studied in rats using the method of pendular perfusion. One and four weeks after i.p. application of 100 mg HCB/kg body weight segments of jejunum, ileum and colon were perfused with light liquid paraffin or squalane for 5 h. 2. The highest amount of HCB was excreted into jejunum, followed by ileum and colon. After 5 h HCB concentration in jejunal perfusion medium equals that in plasma. 3. Serosal tissue of intestinal segments contained higher HCB concentrations as compared to mucosa. 4. Paraffin treatment decreased the HCB content in both serosal and mucosal tissue of jejunum and ileum but not of colon.
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    Archives of toxicology 48 (1981), S. 1-9 
    ISSN: 1432-0738
    Keywords: Placental transfer ; Organogenesis ; Rat ; Embryotoxicity ; Toxicokinetics ; Thiamphenicol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Measurement of thiamphenicol transfer to the rat embryo during organogenesis was performed as one step of the determination of possible drug embryotoxicity in man. Extrapolation of data on animal embryotoxicity to man will only become possible when data on the toxicokinetic properties of the substance under investigation are available for both animal and man. 1) Thiamphenicol, given between day 11.5 and 14 of rat gestation, rapidly reached the embryo; 4–6 h after single i.v. or s.c. injection, embryonic and maternal thiamphenicol levels became equal and decreased from that time on at the same rate. 2) No evidence was found for development of a placental barrier with increasing placental function. The same dose applied at different developmental stages yielded the same embryonic drug concentrations. 3) Elimination via kidney (unchanged) or bile (glucuronide), may become rate-limiting for thiamphenicol excretion. Doses exceeding 50 mg/kg (i.v.) or approx. 100 mg/kg (s.c.) yielded thiamphenicol levels higher than those expected from linear dose-concentration relationships. 4) Drug concentrations (〉 3–5 μg/g wet weight) obtained with dosing regimens (〉 100 mg/kg/day) used for experimental induction of embryolethality in rats are equal to those necessary for inhibition of mitochondrial protein synthesis in vitro and to those necessary for treatment of bacterial infections in man.
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    Archives of toxicology 48 (1981), S. 41-50 
    ISSN: 1432-0738
    Keywords: Cyanide ; Zinc ; Copper ; Manganese ; Atomic absorption spectrophotometry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Single doses of sodium cyanide (60 μmol/kg body weight s.c.) were administered to male Sprague-Dawley rats. The effect of this poison on the content of the trace elements zinc, copper and manganese was investigated in various organs after 30 min, 2 h, 24 h, 48 h and 1 week. The zinc content in the liver was elevated 24 h after this sublethal cyanide dose (by approximately 20%). In contrast, the copper content in the kidneys was lowered (by approximately 15%) at the same time. Almost similar changes were observed in the same organs after daily administration of the poison for 5 days. For comparison, another group of rats was allowed to respire for 30 min the air that contained only 10% oxygen. The above changes in the trace element concentrations were not observed under these conditions. After sublethal cyanide poisoning there seemed be slight but specific alterations in the trace element concentrations in the liver and kidneys of rats. On the other hand, there were no alterations in serum, heart, lung, brain, muscle, bone or testes. Up to now there is no clearcut explanation for the development and the possible biochemical importance of these results.
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  • 83
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    Archives of toxicology 48 (1981), S. 271-279 
    ISSN: 1432-0738
    Keywords: Thallium (I) ions ; Colonic secretion ; Voltage clamp ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract 1. Movement of thallium (I) ions across the mucosal epithelium of descending rat colon, stripped of the muscularis externa in vitro was determined under voltage clamp conditions. 2. The unidirectional fluxes of thallium (I) ions from mucosal to serosal side (M → S) and in the opposite direction (S → M) were measured at 0 mV. A net flux of thallium (I) ions was observed from serosal to mucosal side (0.216 nmoles · cm−2 · h−1) in other words, the mucosal epithelium is apparently asymmetric for the movement of thallium (I) ions. 3. The investigations were carried out on the range of −30 mV up to +30 mV from mucosal to serosal side. Thallium (I) ions move from mucosal to serosal side (M → S) by diffusion only (Pi = 0.119 cm · h−1), whereas into the opposite direction (S → M) thallium (I) ions in addition to a voltage-dependent component are transported against an electrical gradient.
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  • 84
    ISSN: 1432-0738
    Keywords: Polychlorinated paraffins and terphenyls ; Liver ; Cytochrome P-450 ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The polychlorinated terphenyl Aroclor 5460 and the polychlorinated paraffins Witaclor 171 P and Witaclor 149 increased to different degrees the total microsomal concentration of cytochrome P-450 in the rat liver after intraperitoneal injection of 0.3, 1.0, and 1.0 g · kg−1 body weight, respectively, each day for four days. The multiple forms of cytochrome P-450 were affected differently with an induction of RLvMc P-45050 and RLvMc P-45054 by all chemicals, and an additional induction of RLvMc P-45055 by the polychlorinated terphenyl. The rat liver weights were extensively increased after treatment with the polychlorinated paraffins. Alterations were found in the in vitro metabolism of biphenyl, benzo(a)pyrene and the steroid hormones, 4-androstene-3,17-dione and 5α-androstane-3α,17β-diol, after exposure to all chemicals. Changes in the in vitro formation of benzo(a)pyrene metabolites were found to correlate with changes in the multiple forms of cytochrome P-450. The present study demonstrate that only limited information can be obtained from alterations in the total concentration of cytochrome P-450 and show the importance of studying changes in the multiple forms and the metabolism of different substrates. Our results further indicate that exposure to any of the investigated polychlorinated chemicals may alter the biological effects of other environmental contaminants, drugs and endogenous substances which are metabolized by the cytochrome P-450 enzyme system.
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  • 85
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    Archives of dermatological research 271 (1981), S. 275-282 
    ISSN: 1432-069X
    Keywords: Percutaneous absorption ; Griseofulvin ; Proquazone ; Rat ; Human skin ; Percutane Absorption ; Griseofulvin ; Proquazon ; Ratte ; menschliche Haut
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Salben mit Griseofulvin respektive Proquazon wurden aus Monoglyceriden mittlerer Kettenlänge und einem aprotischen Lösungsmittel, Glycerinformal, hergestellt und auf dem Rücken von Gallefistelratten appliziert. Die percutan resorbierten Mengen sowie die Permeabilitätskonstanten sind für beide Wirkstoffe wesentlich höher nach Applikation der Salben als nach Applikation von einfachen Wirkstofflösungen ohne Monoglyceride. Die Verteilung der markierten Wirkstoffe in Rattenhaut wurde durch Mikroautoradiographie kontrolliert. Die Konzentrationen der Wirkstoffe in den einzelnen Schichten von menschlicher Haut sowie die mittleren Penetrationsraten wurden 16 h nach Applikation der Salben auf isolierte menschliche Haut bestimmt. Monoglyceride mittlerer Kettenlänge erhöhen die Permeabilität des Stratum corneum für gelöste Wirkstoffe wesentlich.
    Notes: Summary Ointments containing griseofulvin and proquazone, respectively, were made up of monoglycerides of medium chain length and an aprotic solvent, glycerinformal. The ointments were applied topically on the back of bile cannulated rats. The total amount absorbed percutaneously and the permeability constants of both drugs were considerably higher for the ointments than for simple solutions of the drugs without monoglycerides. Distribution of the labeled drugs in rat skin has been demonstrated by microautoradiography. Concentrations of the drugs in the different layers of human skin together with the medium flow rates have been determined 16h after administration of the ointments onto isolated human skin. Monoglycerides of medium chain length enhance significantly the permeability of the stratum corneum for solutes.
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    Experimental brain research 41 (1981), S. 135-145 
    ISSN: 1432-1106
    Keywords: Supraoptic nucleus ; Rat ; Antidromic ; Phasic ; Recurrent inhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Antidromically identified neurones were recorded from the supraoptic neucleus of urethane-anaesthetised rats. In test periods of about 10 min, each recorded action potential was followed 1 ms later by a shock to the neural stalk. In phasically firing cells, this stimulation consistently modified the observed firing pattern: burst length was shortened but intraburst activity was unchanged. The stimulation invaded most supraoptic neurones antidromically, but antidromic spikes evoked in the recorded neurone were extinguished by collision. Thus, the observed changes in firing pattern were probably the consequence of interaction between the recorded unit and other neurones projecting to the neural stalk — most probably other supraoptic neurones. The behaviour of continuously firing supraoptic neurones was studied following single shocks and following trains of shocks. The results suggest that the widely reported evidence for recurrent inhibition in the rat supraoptic nucleus has been misinterpreted, and that inhibition cannot be demonstrated in most supraoptic neurones following single shocks to the neural stalk. However, the experiments using trains of shocks produced evidence consistent with a complex interaction between magnocellular neurosecretory cells involving both excitation and inhibition.
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    Experimental brain research 41 (1981), S. 184-187 
    ISSN: 1432-1106
    Keywords: Visual cortex ; Layer I ; Afferent connections ; HRP ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The afferent connections to layer I of the visual cortex, area 17, of the albino rat were studied using the retrograde transport of horseradish peroxidase (HRP). In all animals examined, the majority of labeled cells were observed in the dorsal lateral geniculate nucleus and in the lateral posterior nucleus. In addition, in one-half of the animals examined labeled cells were also present in the posterior complex of the thalamus and in the ventromedial nucleus. Finally, in three cases a few HRP-positive neurons were observed in the locus coeruleus and in the dorsal raphe nucleus.
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    Experimental brain research 41 (1981), S. 316-328 
    ISSN: 1432-1106
    Keywords: Orienting behavior ; Superior colliculus ; Visual cortex ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of visual cortical and subcortical lesions on orienting behavior was assessed by examining the rats' ability to interrupt an ongoing response and perform appropriate head and postural adjustments to repeatedly presented auditory or apparently moving visual stimuli. Large lesions of the entire superior colliculus (SC) or the deep layers of the SC did not result in visual agnosia or the inability to perform the motor responses involved in orienting. Rather, the orienting response simply was not emitted to visual stimuli that the intact rat treated as less salient, but was to those it treated as more salient. Lesions of either the superficial layers of the SC or visual cortex also did not completely prevent orienting to very salient, apparently moving visual stimuli, but did produce changes in the number of responses made to such stimuli and in the occurrence of other components of orienting behavior. It was suggested that the SC and visual cortex play a modulatory role in orienting behavior and that stimulus characteristics must be considered in the development of neuronal models of orienting behavior.
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    Intensive care medicine 7 (1981), S. 115-119 
    ISSN: 1432-1238
    Keywords: Ultrastructure ; Platelets ; Leucocytes ; Microaggregates ; Microfilters ; Microemboli ; Vascular integrity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Electron microscopy of citrate-phosphatedextrose (CPD) buffered bank blood performed over 21 days shows that the normal architecture of erythrocytes, platelets and leucocytes disappears and that deformed organelles, leucocyte “ghosts”, cell fragments and microaggregates accumulate. Leucocytes and platelets emerge as the most sensitive indicators of blood deterioration showing profound morphological changes from the first day. Microaggregates which passed through a 20-μm high capacity transfusion filter were identified as platelet conglomerates, leucocyte “ghost” and platelet-leucocyte “ghost” coaggregates with diameters of 6–20, 20–30 and 30–40 μm respectively. of these aggregates present in the filtrate, 62% fell into the size range of 20–40 μm. The composition of microaggregates varies with storage time, the platelet conglomerates appear first during or after Day 1, leucocyte “ghosts” after Day 5 followed by platelet-leucocyte “ghost” coaggregate formation. At this stage the number of intact leucocytes and platelets is reduced and the filtrate shows an abundance of leucocyte debris. Microfiltration would thus appear to reduce but not eliminate the danger of microembolism and damage to capillary endothelium.
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    Archives of microbiology 130 (1981), S. 204-212 
    ISSN: 1432-072X
    Keywords: Agmenellum quadruplicatum ; Nitrogen starvation ; Ultrastructure ; PATO poststain ; Cyanobacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of nitrogen limitation on the ultrastructure of the unicellular cyanobacterium, Agmenellum quadruplicatum, were studied by thin sectioning transmission electron microscopy. Nitrogen became limiting for growth 14–15 h after transfer to nitrogen-limiting medium, but cultures retained full viability for at least 45 h. The c-phycocyanin: chlorophyll a ratio and cellular nitrogen content of the culture dropped rapidly after 14–15 h, as a progressive deterioration of major cell structures took place. Phycobilisomes were degraded first, followed by ribosomes and, then, thylakoid membranes. These structures were virtually depleted from the cells within 26 h. Intracellular polysaccharide accumulated in place of the normal cell structures throughout this period. Nitrogen limitation did not affect polyphosphate bodies, carboxysomes, lipid granules, the cell envelope, or the extra-cellular glycocalyx. All of the ultrastructural changes resulting from nitrogen limitation were reversed upon addition of nitrate to a starved culture. Most cell structures were restored within 3 h, and restoration was complete within 9 h.
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    Archives of dermatological research 270 (1981), S. 403-411 
    ISSN: 1432-069X
    Keywords: Spontaneously regressing plane warts ; Activated macrophage ; Lymphocyte ; Ultrastructure ; Spontan zurückgehende Plattenwarze ; aktivierte Makrophage ; Lymphocyte ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Plane Warzen in der frühesten klinischen Phase der spontanen Involution wurden elektronenmikroskopisch untersucht. Es wurde gezeigt, daß Makrophagen und Lymphocyten in die Epidermis einwandern und daß die Zahl der ersteren die der letzteren überschritt. Die Lymphocyten zeigten Pseudopodien an der Oberfläche und diese drangen zuweilen in die epidermischen Zellen ein. An der Berührungsfläche der Makrophagen und der epidermalen Zellen verschwanden häufig Membranen beider Zellen und gelegentlich wurde ein Teil des Cytoplasmas und auch des Nucleus der Makrophagen von den Zellen der Epidermis aufgenommen. Außerdem wurde ein davon unabhängiger partieller Verlust der Zellmembranen der Makrophagen beobachtet. Diese ultrastrukturellen Verhältnisse zeigen, daß in der spontan zurückgehenden planen Warze eine verringerte Stabilität der Makrophagenmembranen in Gegenwart von Lymphocyten sich entwickelt, wie sie in der durch BCG und anderen Ursachen zerstörten Tumorzelle beobachtet wird, und daß die spontane Involution ein Abstoßungs-Phänomen darstellen kann.
    Notes: Summary Plane warts were examined at the earliest phase of spontaneous involution using an electron microscopy. Macrophages outnumbered lymphocytes in invading the epidermis. Lymphocytes exhibited pseudopods on the surface which occasionally reached into the epidermal cells. The cell membranes of both macrophages and epidermal cells frequently disappeared on the contacting surface and on occasion part of the cytoplasm and even the nucleus of macrophages invaded the epidermal cells. The macrophages showed an independent partial loss of their cell membranes with a subsequent outpour of their contents. This ultrastructural feature indicates that in spontaneously regressing plane warts the depressed membrane stability of macrophages as observed in BCG and other-induced tumor cell destruction also occurs in the presence of lymphocytes. Therefore, the spontaneous involution may represen a rejection phenomenon.
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  • 92
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    Archives of dermatological research 271 (1981), S. 237-240 
    ISSN: 1432-069X
    Keywords: Dence-cored filamentous body ; Mycosis fungoides ; Ultrastructure ; Dense-cored filamentous body ; Mycosis fungoides ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 93
    ISSN: 1432-0584
    Keywords: Immunoprecipitation ; Immature antigens ; Mouse ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Rabbit antisera directed against erythrocytes from anemic mice or from newborn rats, once absorbed on homologous normal adult erythrocytes, recognize antigens present respectively on immature erythrocytes from anemic adult mice or rats (Im M and Im R antigens). Using iodinated immature erythrocytes from both species, homologous sera precipitated two populations of antigens showing 230,000 D and 95,000 D molecular weights. Im M antigens (230,000 and 95,000 D) were partially precipitated using anti-Im R serum. After total absorption of the sample by anti-Im R serum, both 230,000 and 95,000 D antigens were still immunoprecipitated using anti-Im M serum. Similar results were obtained using Im R antigens and anti-Im M serum then anti-Im R serum. This demonstrates that some Im specificities are common to rat and mouse while others, showing identical molecular weights, are species-specific.
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  • 94
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    Pflügers Archiv 391 (1981), S. 200-207 
    ISSN: 1432-2013
    Keywords: Chronic stimulation ; Fast muscle ; Slow muscle ; Contractile properties ; Muscle fatigue ; Histochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Leg muscles of adult rats were stimulated chronically at a low-frequency, and the histochemical reactions of various enzymes (succinic dehydrogenase, mitochondrial α-glycerophosphate dehydrogenase, phosphorylase, alkali-ATPase and acid-ATPase), capillary density, resistance to fatigue, and contractile properties were studied. Following stimulation, the histochemical properties of muscle fibres in the fast extensor digitorum longus (EDL) and tibialis anterior (TA) muscles became similar to those of the majority of fibres in the slow soleus muscle. In the soleus muscle, the histochemical properties of the few fast type fibres became similar to the majority of ‘slow’ fibres so that its fibre composition was homogeneously ‘slow’. The stimulated fast muscles also had higher capillary density and were more resistant to fatigue than normal. Despite the prolonged stimulation, the twitch duration of the fast muscles was little changed. This result differs from the findings obtained previously for the rabbit and cat, which show that slowing of contraction can be achieved by low-frequency activity of similar duration. Thus it may be that there is a species difference regarding the readiness with which the transformation of fast to slow muscles can be brought about.
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  • 95
    ISSN: 1432-2013
    Keywords: Hepatic blood flow ; Hepatic clearance ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two new methods are described to measure hepatic blood flow in the anaesthetized rat. These methods are based on the fractional clearance and extraction of indocyanine green, which is removed by hepatocytes, and of colloidal radiogold, which is removed by Kupffer cells. Hepatic blood flow was found to be 2.11±0.35 ml·min−1·g liver−1 (mean ±SD) and 2.01±0.31 ml·min−1·g liver−1, respectively, with these two substances (P〉0.80).
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  • 96
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    Psychopharmacology 74 (1981), S. 374-378 
    ISSN: 1432-2072
    Keywords: Lithium ; Li+ disposition ; Na+-dependent Li+ countertransport process ; Guinea-pig ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats or guinea-pigs were given LiCl acutely (2 mmol/kg IP or intragastrically) or chronically (daily doses 0.6–4 mmol/kg) and plasma, erythrocytes, kidney, liver and brain were analysed for Li+. Generally, after acute LiCl, tissue Li+ levels followed changes in plasma Li+ levels. However, brain Li+ concentrations changed more slowly and in the rat, but not in the guinea-pig, paralleled erythrocyte Li+ concentrations. Li+ was absorbed more slowly from the gastrointestinal tract of the rat. After chronic LiCl, the erythrocyte: plasma Li+ ratio was about 0.1 in the guinea-pig and about 2 in the rat. Relative Li+ tissue concentrations were as follows: guinea-pig, plasma〉kidney〉liver〉brain〉 erythrocyte; rat≫erythrocyte=brain〉liver=plasma. A Na+-dependent Li+ efflux was demonstrated in the erythrocytes of the guinea-pig and human, but not the rat. This process was inhibited by phloretin (0.2 mM), but not frusemide (2.0 mM). The marked differences in the activity of the erythrocyte Na+-dependent Li+ countertransport process in the guinea-pig and rat could extend to other tissues and explain the observed interspecies differences in tissue Li+ distribution.
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  • 97
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    Psychopharmacology 75 (1981), S. 236-239 
    ISSN: 1432-2072
    Keywords: Water lick paradigm ; Punishment suppressed behaviour ; Conflict ; Anxiolytics ; Serotonin antagonism ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A modified water-lick conflict paradigm is described, using trained rats for up to 35 weekly test sessions under 48 h of water deprivation. The rats rapidly became maximally suppressed by the punishment. This suppression was attenuated by the anxiolytics lorazepam, diazepam, phenobarbital, and meprobamate. The potentially anxiolytic drug CL 218872 and the anticonvulsant drug valproate sodium were also active. The antiserotonin drugs methysergide, cyproheptadine, cinanserin and parachlorophenylalanine were all inactive, as were several other distinct classes of psychotropic drugs including propranolol, clonidine, THIP, theophylline, chlorpromazine, paroxetine and ethanol. The paradigm proved reliable, reproducible and useful for large scale investigations. Furthermore, it may provide means for detailed neuropharmacological and anatomical studies.
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  • 98
    ISSN: 1432-2072
    Keywords: Ovariectomy ; Castration ; Chronic LiCl treatment ; Apomorphine ; Stereotyped behavior ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of ovariectomy, castration, and chronic lithium chloride treatment on stereotyped behavior (SB) induced by apomorphine (APO) (0.3–0.6 mg/kg) were investigated in rats. Duration of stereotyped behavior (interval between APO injection and termination of SB) increased in ovariectomized rats compared to female control rats. Castration had no effect on the duration of stereotyped behavior. On the other hand, ovariectomized rats that were treated chronically with LiCl (2 mEq/kg daily) showed no difference in duration of stereotyped behavior compared to female controls chronically treated with LiCl. Neither treatment group showed a significantly altered intensity of stereotyped behavior compared with the appropriate control. These findings are consisten with the hypothesis that estrogen deficit contributes to a greater incidence of neuroleptic-induced tardive dyskinesia in postmenopausal women than in men of comparable age. Furthermore, LiCl may attenuate the symptoms associated with increased postsynaptic dopamine receptor sensitivity following ovariectomy.
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  • 99
    ISSN: 1432-2072
    Keywords: Ethanol tolerance ; Serotonin ; Norepinephrine ; Dopamine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats were permanently depleted of brain dopamine (DA), serotonin (5-HT), 5-HT+norepinephrine (NE), or NE +DA by intraventricular injection of either 5,7-dihydroxytryptamine (5,7-DHT) or 6-hydroxydopamine (6-OHDA) with or without pretreatment with desmethylimipramine (DMI). Following 1 week of recovery from surgery, daily treatment with ethanol (5 g/kg, PO) or isocaloric sucrose was carried out for a period of 20–25 days. Testing at 5-day intervals showed that chronic ethanol treatment produced tolerance to the hypothermic and motor impairing effects of ethanol. Depletion of 5-HT alone retarded tolerance, while depletion of NE or DA alone produced no effect. Combined depletion of both NE and 5-HT, however, completely inhibited tolerance development. The inhibition of tolerance development by combined depletion of both NE and 5-HT is dicussed in terms of a reciprocal relationship between these two systems.
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  • 100
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    Neurosurgical review 4 (1981), S. 17-31 
    ISSN: 1437-2320
    Keywords: Astrocytoma ; Oligodendroglioma ; Ultrastructure ; Astrocytom ; Oligodendrogliom ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 7 Oligodendrogliome, davon 2 mit uniformem Zell-Typ, 4 mit Zell- oder Gewebs-Unregelmäßigkeit, 1 mit glioblastomatösen Veränderungen wurden elektronenmikroskopisch untersucht. Die Tumorzellen zeigten 2 Haupttypen mit morphologischen Übergängen zwischen beiden auf. Die Hauptformen wurden als Typ 1 (undifferenziert) und 2 (differenziert) definiert, gestützt auf die Anzahl anaplastischer Zellen im jeweiligen Tumor und auf die Beobachtung nicht-neoplastischer Oligodendrocyten nach Mori and Leblond (21). Die meisten Tumorzellen aller Fälle wiesen ähnliche licht- und elektronenmikroskopische Charakteristika auf, einschließlich der Zell-Anordnung und ihrer Tendenz, zytoplasmatische Fortätze zu bilden. Diese Befunde waren auch in den glioblastomähnlichen Tumoren zu erkennen und bestätigen damit deren Oligodendrogliom-Komponente. Außerdem fand man regelmäßig in allen Tumoren eine Zunahme der Größe und Zahl der Mitochondrien, reichlich intrazytoplasmatische Strukturen und Mikrotubuli. Auch Zellen mit zytoplasmatischen Filamenten waren vorhanden, die als reaktive Astrocyten oder als oligodendrogliale Tumorzellen angesehen wurden. Daher scheinen weder zytoplasmatische Filamente noch Mikrotubuli ein spezifisches morphologisches Kriterium für Oligodendroglia oder Astrocyten zu sein. Das Überwiegen einer dieser beiden Strukturen erlaubt jedoch eine zytogenetische Zuordnung. Die zytologischen Charakteristika sind zwar keine spezifischen morphologischen Kriterien; die Feststellung ihrer Anwesenheit gibt jedoch wichtige diagnostische Informationen.
    Notes: Summary Seven Oligodendrogliomas (2 with uniform cell type, 4 with cellular or tissue variability, and 1 with glioblastomatous changes) were examined ultrastructurally. The tumor cells were of two principal types with morphologic transitions between the two main types. The two principal cell types were identified as type 1 (undifferentiated) and type 2 (differentiated) on the basis of the number of anaplastic cells in an individual tumor and on the observations of Mori and Leblond (21) on non-neoplastic oligodendrocytes. Most of the tumor cells in all tumors exhibited similar histologic and ultrastructural characteristics including their arrangement and their tendency to form cytoplasmic processes which sometimes formed short stacks. These features were also recognizable in the glioblastomatous example and confirmed the presence of an oligodendroglial component. In addition to these characteristics, an increase in size and number of mitochondria, abundant intracytoplasmic structures, microtubules were regularly present in virtually all tumor cells. Cells rich in cytoplasmic filaments were present. These were identified as reactive astrocytes or as oligodendroglial tumor cells. Thus neither cytoplasmic filaments nor microtubules appear to be specific morphological markers for oligodendroglia or astrocytes; only the predominance of one of these structures permits cytogenetic identifications. The cytologic characteristics are not specific morphologic markers; however, recognition of their presence provides important diagnostic information.
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