Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 10 (1974), S. 37-44 
    ISSN: 1432-0428
    Keywords: Experimental insulinoma ; experimental nesidioblastoma ; experimental islet cell tumor in rats ; immunoreactive insulin content of experimental insulinomas ; ultrastructure of experimental insulinomas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Young male Holtzman rats were injected intravenously with 50 mg/kg of Streptozotocin, preceded and followed by a single intraperitoneal injection of 350 mg/kg of nicotinamide, according to the method of Rakieten et al. [16]. After 245 to 323 days, 27 pancreatic islet cell tumors measuring up to 0.6 cm were demonstrable in 20 of 41 rats so treated; they were solitary in 15 and multiple (two or three neoplasms each) in five animals. It was not possible to distinguish between tumor-bearing and tumor-free rats on the basis of periodic blood sugar determinations and serum insulin assays. Mean insulin concentration in grossly tumor-free pancreatic specimens was 0.661 units of insulin/g of wet tissue, but amounted to 5.385 units/g in specimens containing tumor. The islet cell tumors were rounded and well delineated. They were located in all parts of the pancreas. In general, their cells stained deeply with aldehyde-fuchsin. Ultra-structurally, most tumors consisted of well granulated B cells. A or D cells were not encountered while occasional EC cells were identified. Nucleoli were frequently prominent. Some necrotic B cells and others with few or unusually small secretory granules were present. Extravasated erythrocytes as well as hemosiderin deposits were seen in many tumors, and tumor cell particles were occasionally noted within the lumina of capillaries. Distant metastases were not demonstrable in this group of animals.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 7 (1971), S. 189-194 
    ISSN: 1432-0428
    Keywords: Blood lipids ; rabbits ; induction of hyper-cholesterolaemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les valeurs des lipides sanguins ont été déterminées chez 48 lapins normaux, 56 lapins sub-diabétiques et 6 lapins manifestement diabétiques par l'alloxane, avant et après l'induction d'une hypercholestérolémie expérimentale. Le sub-diabète, provoqué par de petites doses d'alloxane, ou par des injections séquentielles de cortisone et d'alloxane, est caractérisé par une glycémie normale évoluant vers l'hyperglycémie à la suite de petites injections répétées de cortisone normalement non-diabétogènes. Avant l'administration de cholestérol, les lapins sub-diabétiques atteignaient des taux considérablement plus élevés de cholestérol, de phospholipides, d'acides gras non-estérifiés et de lipides totaux que les animaux métaboliquement normaux. Les taux correspondants (avant l'administration de cholestérol) étaient également plus élevés chez les lapins diabétiques par l'alloxane que chez les lapins normaux, mais leurs valeurs moyennes de cholestérol et de phospholipides étaient plus basses que chez les animaux sub-diabétiques. Au cours de l'administration de cholestérol, les moyennes de toutes les fractions lipidiques, spécialement chez les animaux sub-diabétiques et diabétiques par l'alloxane, augmentaient considérablement pendant 8 semaines; par la suite elles avaient tendance à diminuer mais continuaient à rester anormalement élevées, et seulement de petites différences persistaient entre les groupes expérimentaux.
    Abstract: Zusammenfassung Bei 48 gesunden, 56 subdiabetischen und sechs alloxan-diabetischen Kaninchen wurden die Blutlipoidwerte vor und während einer experimentell induzierten Hypercholesterinämie bestimmt. Subdiabetes wurde mit kleinen Alloxandosen oder mit einer Kombination von Cortison und Alloxan erzeugt; subdiabetische Tiere werden nur nach zusätzlichen, normalerweise nicht diabetogenen kleinen Cortisondosen hyperglykämisch. Bereits vor der Verfütterung von Cholesterin wiesen die subdiabetischen Kaninchen deutlich erhöhte Cholesterin-, Phospholipoid-, Fettsäure-und Gesamtlipoidwerte im Blut auf. Auch bei den alloxandiabetischen Tieren waren die entsprechenden Werte erhöht, beim Cholesterin und den Phospholipoiden jedoch weniger eindeutig. Während der ersten acht Wochen der Cholesterinverabreichung stiegen alle Lipoidfraktionen, vor allem bei den subdiabetischen und alloxandiabetischen Tieren, stark an. Danach zeigte sich eine leicht abfallende Tendenz, wobei sich die Unterschiede zwischen den experimentellen Gruppen gleichzeitig verringerten.
    Notes: Summary Blood lipid values were determined in 48 normal, 56 subdiabetic and 6 overtly alloxan-diabetic rabbits before and after the initiation of experimental hypercholesterolaemia. Subdiabetes, induced by small doses of alloxan or by sequentially administered injections of cortisone and alloxan, is characterized by normoglyaemia changing to hyperglycaemia following repeated, normally nondiabetogenic small cortisone injections. Before cholesterol feeding, the subdiabetic rabbits attained considerably higher cholesterol, phospholipid, nonesterified fatty acid and total lipid levels than did the metabolically normal animals. The corresponding prefeeding levels of the alloxan-diabetic rabbits were also higher than normal, but their average cholesterol and phospholipid values remained lower than in the subdiabetic animals. During cholesterol feeding, the averages of all lipid fractions, especially in the subdiabetic and alloxan-diabetic animals, rose considerably for 8 weeks; thereafter, they tended to decline but continued to remain abnormally high, and only minor differences between the experimental groups persisted.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0428
    Keywords: B cell degranulation ; B cell necrosis ; encephalomyocarditis virus ; histiocytic response ; hyperglycaemia ; insulin immunoassay ; mice ; viral infection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Soixante-dix-sept souris mâles CD-1, âgées de 12 à 16 semaines ont reçu une injection sous-cutanée du variant M du virus de l'encéphalo-myocardite (BMC). Treize souris recevant une injection d'eau salée, servaient de témoins. Les 45 souris survivantes ayant reçu le virus ont été sacrifiées à des intervalles allant de 24 h à 15 jours après l'injection. Les valeurs de la glycémie étaient nettement élevées au cours des deux premiers jours et de nouveau entre le septième et le quinzième jour de l'expérience. Le dosage immunologique du tissu pancréatique a révélé une baisse de la concentration moyenne d'insuline de moitié par rapport aux souris témoins. La recherche des virus dans des suspensions de pancréas 2 jours et demi à 9 jours et demi après l'infection a révélé des titres significatifs, déterminés par l'effet cytopathque. On n'a détecté aucune modification morphologique au cours des deux premiers jours après l'injection du virus. Par la suite on a observé au microscope à lumière une rupture de l'architecture des cellules insulaires, une nécrose des cellules B, une dégranulation des cellules B et des infiltrats cellulaires mononucléaires. Ultrastructuralement, la rupture du matériel nucléaire, la dilatation de l'espace périnucléaire et l'apparition de vésicules cyto plasmiques remplies de fine substance granulaire ont été vues dans les cellules B au cours de la première phase de l'expérience. La réponse histiocytaire et l'élimination des cellules B lésées étaient rapides. Des formations cristallines de virus n'ont pas été identifiées. Dans plusieurs cellules B survivantes on a noté une faible granulation et une dilatation des unités du réticulum endoplasmique. Les cellules acineuses exocrines présentaient des lésions d'étendue limitée. Aucune lésion des glandes salivaires n'a été identifiée.
    Abstract: Zusammenfassung Bei 77 männlichen, 12 bis 16 Wochen alten CD-1-Mäusen wurde subkutan die M Variante des Enzephalomyokarditis-Virus (EMC-Virus) injiziert; 13 Kontrolltiere erhielten NaCl-Lösung statt des Virus. Die 45 überlebenden virus-infizierten Mäuse wurden 24 Std bis 15 Tage später getötet. Die Blutzuckerwerte waren während der ersten zwei Tage sowie vom 7. bis 15. Tag des Experiments deutlich erhöht. Die durchschnittliche Insulinkonzentration der Bauchspeicheldrüse sank gegenüber den Kontrollen auf die Hälfte. Virus konnte in den Bauchspeicheldrüsen 2 1/2 bis 9 1/2 Tage nach der Infektion gewebekulturell nachgewiesen werden. Lichtmikroskopisch wurden in den ersten beiden Tagen keine Veränderungen entdeckt. Danach zeigten sich eine Auflockerung der Inselstruktur mit Nekrose und Degranulierung von B-Zellen sowie mononukleäre Infiltrate. Ultrastrukturell ließen sich zuerst Kernschäden und ein Auftreten von Cytoplasmabläschen mit fein granulierter Substanz in den B-Zellen beobachten. Kurz danach kam es zu einer histiozytären Reaktion mit rascher Beseitigung der geschädigten B-Zellen. Viruskristalle ließen sich nicht nachweisen. Viele überlebende B-Zellen zeigten eine Verminderung der Anzahl der Sekretgranula sowie erweiterte Räume des endoplasmatischen Reticulum. Die exkretorischen Pankreasanteile wiesen nur geringe, die Kopfspeicheldrüsen keinerlei morphologisch faßbare Schäden auf.
    Notes: Summary Seventy-seven male, 12 to 16 week old CD-1 mice were injected subcutaneously with the M variant of the enoephalomyocarditis (EMC) virus. Thirteen saline-injected mice served as controls. The 45 surviving virus-injected mice were sacrificed at intervals ranging from 24 h to 15 days following injection. Blood glucose values were distinctly elevated during the first 2 days and again between the seventh and fifteenth day of the experiment. Immunoassay of pancreatic tissue revealed a lowering of the mean insulin concentration to one half of that of the control mice. Pancreas suspensions assayed for the presence of virus 21/2 to 91/2 days after infection yielded significant titers as determined by cytopathic effect. No morphologic changes were detected during the first 2 days after virus injection. Thereafter, disruption of islet cell architecture, B cell necrosis, B cell degranulation, and mononuclear cell infiltrates were noted by light microscopy. Ultrastructurally, disruption of nuclear material, dilatation of the perinuclear space, and the appearance of cytoplasmic vesicles filled with fine granular substance were seen in B cells during the early phase of the experiment. Histiocytic response and removal of damaged B cells was prompt. Crystalline viral arrays were not identified. Poor granulation and dilatation of the units of the endoplasmic reticulum were noted in many surviving B cells. Damage to exocrine acinar cells was of limited extent. No salivary gland lesions were identified.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 13 (1977), S. 331-337 
    ISSN: 1432-0428
    Keywords: Cortisone ; B cell ; blood glucose ; experimental diabetes ; islet hyperplasia ; rat ; streptozotocin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cortisone pretreatment considerably enhances the mortality of young, male, streptozotocin-injected Holtzman rats. In those that survive, cortisone pretreatment decreases the ensuing hyperglycaemia, extends the period during which streptozotocin-induced B cell damage can be observed from less than two to as much as four to seven days and permits the persistence of poorly granulated B cells in such animals. These effects are at least partially attributable to a cortisone-induced augmentation of the total B cell mass. Compared with the high degree of protection against alloxan-induced damage afforded the pancreatic B cells of cortisone-pretreated rabbits, the protective effect of cortisone against B cell destruction in streptozotocin-injected rats is thus much more limited in scope. Species differences as well as differing pathogenetic mechanisms may account for these results.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-0533
    Keywords: Electron Microscopy ; Encephalomyocarditis (EMC) Virus ; Neurotrophic Viruses ; Viremia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary One hundred and eighty 12 week old Swiss mice were injected subcutaneously with 0.1 ml suspensions of the E and M variants of encephalomyocarditis (EMC) virus. Ninety-seven surviving mice were sacrificed at intervals from 24 h to 21 days following injection. The M variant group showed only mild microglial proliferation in the brain, while the E variant group displayed various alterations in the astrocytes and neurons exhibiting loss of nuclear membranes and marked changes in the mitochondria and other organelles. In addition, the neuronal cytoplasm displayed aggregates of fine electron-dense granules on the third day which increased in size during the fifth to seventh day. After 7 days, the neurons contained occasional rhomboid structures composed of rows of parallel arranged granules which were similar to those observed in the viscera after EMC virus infection.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-0533
    Keywords: Early CNS Lesions ; Experimental Hypercholesterolemia ; Subdiabetic Rabbits ; Mitochondrial Alterations ; Endoplasmic Reticulum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Biochemical and morphologic studies were carried out on the early effect of hypercholesterolemia on the central nervous system in both metabolically normal and subdiabetic rabbits. Major biochemical difference was the elevation of non-esterified cholesterol in the subdiabetic animals. Histologically, Alzheimer type II astrocytosis was noted in the basal ganglia of the subdiabetic rabbits during the 4th week. The astrocytosis extended into the entire protion of the cerebrum and cerebellum during 2 to 4 months. In the metabolically normal rabbits on the cholesterol diet, on the other hand, similar astrocytic changes were noted after 2 months. Despite the fact that cholesterol crystals had frequently been noted in the capillary walls of the viscera after the 2nd week, similar changes were not observed in the blood vessels of the brains of both the subdiabetic and the metabolically normal rabbits during the 4 months of cholesterol feeding. These observations suggest that cholesterol deposits in the vascular walls are determined by the different rates of lipid metabolism in each individual organ.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...