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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 43 (1965), S. 173-174 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Proteolytic proenzymes are activated during incubation of rat pancreas homogenates for 3 and 6 hours at slightly acid reaction. Maximal activation of trypsinogen occured after incubation at pH 4,5 but no trypsin activity could be detected after incubation for 6 hours at pH values above 6. A proteolytic activity which is not identical with trypsin and chymotrypsin showed maximal activation at pH 5.2, and in contrast to trypsinogen, some activation was noted after incubation at pH 6 and above. The activation of this proteolytic “residual activity” could be demonstrated in ischemic pancreatic tissue in vivo, too. The activation of the proteolytic „residual activity“ was strongly inhibited by Trasylol in vitro.
    Notes: Zusammenfassung Während einer kurzfristigen Inkubation von Pankreas-Homogenaten bei schwach saurer Reaktion werden proteolytische Proenzyme in die aktiven Enzyme überführt. Für die Aktivierung von Trypsinogen wurde ein Optimum bei pH 4,5 gefunden, oberhalb von pH 6 wurde keine meßbare Trypsinaktivität erhalten. Dagegen erfuhr die mit Trypsin und Chymotrypsin nicht identische proteolytische „Restaktivität“ eine maximale Aktivierung durch Inkubation bei pH 5,2, auch bei pH-Werten über pH 6 war noch eine erhebliche Aktivierbarkeit nachzuweisen, sie konnte in vitro durch Trasylol stark gehemmt werden.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 44 (1966), S. 282-283 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Todd's andWarren's method of fibrinolysis autographs is able to demonstrate histochemically the activity of proteolytic enzymes in the „autodigestiv-tryptic-pancreatitis“. The distribution of proteolytic activity is corresponding to the autodigestiv necrosis after application of oliven oil or lactic acid.
    Notes: Zusammenfassung Mit einer Modifikation der „fibrinolysis autographs“ nachTodd undWarren läßt sich bei der Olivenöl- und Milchsäure-Pankreatitis histochemisch die Aktivität proteolytischer Fermente nachweisen. Das Verteilungsmuster der proteolytischen Aktivität entspricht topochemisch dem Ausbreitungstyp der autodigestiven Parenchymnekrosen.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 42 (1964), S. 400-402 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary In freshly prepared pancreatic homogenates neither tryptic nor chymotryptic activity can be established by means of specific synthetic substrates. A slight proteolytic activity (“residual proteolytic activity”), however, can be proved by protein substrates (e.g. azo casein). It can scarcely be influenced by several inhibitors of trypsin and chymotrypsin, but it is considerably inhibited by human and rat serum. It is significantly enhanced on the following experimental conditions: 1 Autolysis of pancreatic tissue or homogenatein vitro during 6–7 hours. 2 Experimental acute pancreatitis. The concomitant pancreatitic ascites shows a high proteolytic activity (substrate: azo casein), too.
    Notes: Zusammenfassung In frisch bereiteten Pankreashomogenaten ist mit spezifischen synthetischen Substraten kein aktives Trypsin und Chymotrypsin nachweisbar. Proteinsubstrate (z. B. Azocasein) werden dagegen gespalten. Diese proteolytische „Restaktivität,‘ wird durch Zusatz verschiedener Trypsin-und Chymotrypsin-Inhibitoren kaum beeinflußt, Serum von Mensch und Ratte hemmt jedoch stark. Folgende experimentelle Bedingungen führen zu einer Erhöhung dieser Aktivität. 1 Autolyse von Pankreasgewebe oder -homogenatenin vitro während 6–7 Std. 2 Experimentelle akute Pankreatitis. Der pankreatitische Begleitascites enthält ebenfalls eine von Trypsin und Chymotrypsin verschiedene proteolytische Aktivität gegen Azocasein.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 42 (1964), S. 447-449 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The so-called serum leucine aminopeptidase (LAP) activity is usually determined by cleavage ofl-leucyl-β-naphthylamide, although the “classical” LAP does not take an essential part, if any. The specificity of the enzymes splittingl-leucyl-β-naphthylamide is rather characterized by the designationamino acid arylamidase activity than by LAP. A simplified method for the estimation of amino acid arylamidase activity is described:l-leucyl-p-nitroanilide is employed as a substrate. Liberated p-nitroaniline can be determined by direct photometry at 405 mµ. This activity is elevated e.g. in patients with liver diseases. The levels of true LAP (specific substrate:l-leucinamide) and amino acid arylamidase activity are compared in normal and pathological sera. No correlation was found.l-leucinamide, however, is hydrolyzed to a smaller extent. On the contrary, highly purified preparations of true LAP are extremely more active againstl-leucinamide than againstl-leucyl-p-nitroanilide.
    Notes: Zusammenfassung Die sog. Serum-Leucinaminopeptidase(LAP)-Aktivität wird im allgemeinen durch die Spaltung vonl-Leucin-β-naphthylamid (LEUNA) bestimmt, obwohl die „klassische“ LAP allenfalls nur geringfügig daran beteiligt ist. Die Spezifität der für die Spaltung von LEUNA verantwortlichen Enzyme wird besser durch die BezeichnungAminosäurearylamidase-Aktivität wiedergegeben. Es wird eine wesentlich vereinfachte Methode zur Bestimmung dieser Aminosäurearylamidase-Aktivität beschrieben, indeml-Leucin-p-nitroanilid als Substrat verwendet wird, dessen Spaltprodukt p-Nitroanilin direkt bei 405 mµ photometriert werden kann. Eine Erhöhung der Aminosäurearylamidase-Aktivität ist unter anderem für die Diagnose von Lebererkrankungen von Bedeutung. In normalen und pathologischen Seren wird die echte LAP (spezifisches Substrat:l-Leucinamid) und die Aminosäurearylamidase-Aktivität vergleichend bestimmt. Der Quotient beider Umsatzraten ist nicht konstant;l-Leucinamid wird regelmäßig langsamer hydrolysiert. Dagegen zeigen hochgereinigte Präparationen der echten LAP eine vielfach höhere Aktivität gegenl-Leucinamid als gegenl-Leucin-p-nitroanilid.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary In 82 dogs, both male and female, acute experimental pancreatitis was produced according to the procedure published byElliott, Williams andZollinger. Along with microscopic, histochemical and electron microscopic investigations, changes of enzyme and electrolyte concentrations as well as of the activity of proteinases were studied in order to pursue the pathways of pancreatic disorders. Besides, the examinations included studies on the effects of pancreatitis on the blood clotting mechanism and on changes of plasma volumes. It appears that, after an initial secretory obstruction and enlargement of the isthmic epithelium (“Isthmus blockade”), dilatation of acini and reflux of enzymes at the site of their production can be regarded as the most important lesions. Electron microscopic studies showed an irritation of the basal endoplasmatic reticulum at the beginning of the cellular lesion. In the further course, parapedesis through the cellular membranes can be observed, a phenomenon, the sequelae of which may be paralysis of preterminal or terminal vessels. Stimulation of functioning acinar cells obviously is followed by an “energetic” insufficiency, if ductal obstruction is maintained. When isthmus blockade continues, the initially reversible cellular lesion becomes irreparable, prodominantly because of vascular paralysis and consecutive tissue hypoxia. Enzyme displacement and local hypoxia form a circulus vitiosus which results in a tryptic necrosis. Chymotrypsin, trypsinogen, and trypsin could not be proved. Proteinases which were found effective at a neutral pH, however, appear to be responsible for the enzymatic auto-digestion of the pancreas.
    Notes: Zusammenfassung Bei 82 Hunden beiderlei Geschlechts wurde eine akute Pankreatitis in der Technik nachElliott, Williams undZollinger erzeugt. Pathologisch-anatomische, histochemische und elektronenmikroskopische Untersuchungen wurden den Befunden der Fermententgleisung, der Transmineralisation und Proteinasenaktivität gegenübergestellt, um die „Zündschnur“ des pathischen Geschehens zu verfolgen. Hiernach resultiert neben der „Sekretplombe“ eine Verquellung der Isthmusepithelien — eine „Isthmusblockade“. Die Folge ist eine Acinusdilatation und Enzym- wie Sekretrückstauung im Bereich der Produktionsstätte. Submikroskopisch läßt sich zeigen, daß am Beginn der Zellschädigung eine Irritation des basalen endoplasmatischen Reticulum besteht, in deren weiterem Verlaufe es zum Phänomen der Parapedese über die Zellbasis kommt, deren Folge die Paralyse der präterminalen und terminalen Strombahn sein kann. Die unter Sekretionsreiz gegen Sekretstauung arbeitenden Zellen geraten offenbar in eine „energetische“ Insuffizienz. Der zunächst noch reversible Zellschaden wird bei anhaltender Isthmusblockade durch Paralyse der capillären Strombahn und konsekutive Hypoxie dekompensierbar. Hypoxie und Fermententgleisung potenzieren einander und bilden einen Circulus vitiosus, dessen Folge die tryptische Nekrose ist. Chymotrypsin, Trypsinogen bzw. Trypsin waren nicht bestimmbar. Dagegen wurden im neutralen Bereiche wirksame Proteinasen nachgewiesen, die für die fermentative Autodigestion verantwortlich gemacht werden können. Weiterhin wird die Wirkung der Pankreatitis auf Blutgerinnung, Serumelektrolyte, Serumfermente und Plasmavolumen diskutiert.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 45 (1967), S. 137-140 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary A simple method is presented to eliminate the analytical error which results from interaction of dextrane and inulin. A differentiation can be obtained by incubating the plasma or urine with the anthron reactant at 50° and 70° C for 15 min. This method was found to be useful in calculating the inulin clearance before and after administration of Rheomacrodex.
    Notes: Zusammenfassung Eine einfache Methode zur Elimination des durch Dextrane hervorgerufenen Fehlers bei der Inulinbestimmung wird mitgeteilt. Durch Inkubation mit Anthronreagens bei 50° und 70° C für 15 min werden zwei Meßwerte erhalten, aus denen die Inulin-und Dextrankonzentration nach der Differenzmethode errechnet werden kann. In einem klinischen Beispiel wird die Brauchbarkeit der Methode für die Berechnung der Inulinclearance vor und nach Verabreichung von Rheomacrodex gezeigt. Ohne Korrektur sinkt die errechnete Inulinclearance nach Infusion von 400 ml Rheomacrodex (10%) um 30% ab, während die korrigierten Werte keine Beeinflussung der Inulinclearance durch Rheomacrodex ergeben.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 45 (1967), S. 681-682 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Different noxae produce different forms of pancreatitis. This is an essential basis for judging the success or failure of a protease inhibitor. It is possible to differentiate primary haemorrhagic necrotising non-enzymatic “bile-pancreatitis” from a “lipolytic” and a “proteolytic” form. With the intravenous administration of the inhibitor only some 2% of the total dose arrive the pancreas. Therefore Trasylol® was infused over 12 hours (a dose of 7,5 million KIU, dissolved in 800 ml physiological saline solution). The therapeutic infusion startet immediately after intraductal instillation of lipofundin (a 10% fat emulsion) which induces a mixed form of lipolytic and proteolytic pancreatitis very similar to human “tryptic” pancreatitis. In summary, the conclusions may be reached that the first phase, due to lipase, is uneffected, since it is associated with strictly substrate-specific parenchymal destruction, whereas the second phase, due to proteases, may be partly influenced and ameliorated by Trasylol®. Trasylol® prevents to a large extent intra-pancreatic circulatory disturbance and is able to prevent the sequelae of enzymatic derangement on the heart, liver and kidney. Biochemically, a twofold increase in the perchloric acid soluble inhibitor-content may be detected in the homogenates of pancreas at the end of the experiments.
    Notes: Zusammenfassung Neben einer hämorrhagisch-nekrotisierenden, primär nicht enzymatischen Gallepankreatitis, kann eine lipolytische von einer proteolytischen Variante unterschieden werden. Die „Lipofundinpankreatitis“, als lipolytisch-proteolytische Mischform, entspricht morphologisch am ehesten der sog. „tryptischen Pankreatitis“ des Menschen. An ihr wurde die Wirkung des Proteaseninhibitors Trasylol® im Hundeversuch getestet. Auch durch Trasylolhöchstdosen (7,5 Mill. KIE/12 Std) wird die Ausdehnung der streng substratgebundenen und über die Lipase gestarteten initialen Autodigestionsherde nicht beeinflußt. Dagegen scheint die zweite, an eine Enzymentgleisung gebundene Phase der Parenchymzerstörung, mitigiert zu werden. So wandelt sich der Ablauf der Acinusepithelnekrosen. Das Phänomen der Karyolyse und Karyorhexis, als für die proteolytische Pankreatitis charakteristisch, wird nicht beobachtet. Zudem fehlt der Parenchymuntergang in Anlehnung an das interstitielle Speichelödem. Unter Trasylolschutz kommt es weiterhin nicht zur Entwicklung von Thromben und Arrosionsblutungen im Pankreas und den Folgen der Enzymentgleisung an Herz, Leber und Nieren. Biochemisch läßt sich in den Pankreashomogenaten eine Verdoppelung des bei Versuchsbeginn gemessenen perchlorsäurelöslichen Inhibitorgehaltes ermitteln.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 46 (1968), S. 413-417 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The “unspecific-proteolytic” and “specific-fibrinolytic” activity in sediment and supernatent of leukocytic homogenates were examined in fibrinfree tube assays and on plasminogen-free heatdenatured and plasminogen-containing fibrin plates. Besides an unspecific proteolytic activity effective in the neutral pH-range a plasminogen activator activity was detected in the plasminogen-containing fibrin plates. This activator activity could not be inhibited by EACA in a concentration of 5 × 10−3 M. Leukocytic homogenates containing sediment as well as supernatant did not produce any plasminogen activator activity on plasminogen-containing fibrin plates. The investigations showed the existence of a bovine plasmin inhibitor in the leukocytic supernatant checking the “specific-fibrinolytic” activity of leukocytic sediment.
    Notes: Zusammenfassung In vergleichenden gerinnungsanalytischen und Reagensglasansätzen wurden die Sediment-Fraktion und die Überstand-Fraktion von Leukocyten-Homogenaten auf ihre „unspezifischproteolytische“ und „spezifisch-fibrinolytische“ Aktivität untersucht. Dabei fand sich in der Sediment-Fraktion neben einer im neutralen pH-Bereich wirksamen unspezifischen proteolytischen Aktivität auf plasminogenhaltigen Fibrinplatten eine Plasminogen-Aktivator-Aktivität. Diese Aktivator-Aktivität ist durch EACA in 5×10−3M Konzentration nicht hemmbar. Gesamt-Homogenate, die sowohl Sediment als auch Überstand enthielten, zeigten keine Plasminogen-Aktivator-Aktivität auf bovinen Fibrinplatten. In den vorliegenden Untersuchungen konnte gezeigt werden, daß die Überstand-Fraktion einen Inhibitor für Plasmin enthält, der die „spezifisch-fibrinolytische“ Aktivität der Sediment-Fraktion zu hemmen vermag.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    The journal of membrane biology 159 (1997), S. 127 -135 
    ISSN: 1432-1424
    Keywords: Key words: cAMP — Theophylline — PCMBS — Na+ transport —Bufo viridis— Graphical model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract. The regulation of the voltage-activated chloride current conductance (G Cl ) in toad skin was investigated by the use of the SH reagents N-ethylmaleimide (NEM) and p-chloro-mercuricbenzenesulfonic acid PCMBS. This anion pathway is controlled by a voltage-sensitive gating regulator. Mucosal application of NEM decreased the voltage-activation in a time and concentration dependent manner, half-maximal inhibition being exerted at a concentration of 30 μm within 20 min. At concentrations higher than 100 μm, the voltage-activated G Cl was near-completely and irreversibly inhibited in less than 10 min. Resting, deactivated conductance was essentially unaffected. NEM had no effect on active sodium transport (measured as I sc ) under conditions, which fully dissipated the voltage-activated G Cl . After complete inhibition of the voltage-activated G Cl with NEM, chloride conductance could still be stimulated by CPT-cAMP as in control tissues. Under these conditions, NEM at concentrations above 1 mm decreased G Cl reversibly. Mucosal application of PCMBS at 500 μm inhibited the activated conductance by 35%, which was slightly reversible. Inhibition of voltage-activated G Cl , which was observed after mucosal addition of the membrane-impermeable NEM analogue, eosin-5-maleimide, was completely reversible after washout. This suggests that the binding site for the maleimide is not accessible from the external face of the apical membrane. Brief application of NEM at lower concentrations (1–3 min, ≤100 μm) led to partial inhibition of G Cl , followed by occasionally complete recovery upon washout of NEM. Recovery of voltage-activated G Cl was progressively attenuated and eventually disappeared after subsequent brief applications of NEM. This could reflect recruitment of permeation/control sites from a finite pool. The data are discussed in the frame of a working model for the voltage-activated Cl−-pathway, that contains two principle components, i.e., an anion-selective permeation path which is controlled by regulatory protein(s).
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    The journal of membrane biology 173 (2000), S. 117-125 
    ISSN: 1432-1424
    Keywords: Key words: Mitochondria-rich cells — Tight junctions — Electrophysiology — cAMP — Dinitrophenol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract. The effect of cyanide (CN−) on voltage-activated or cAMP-induced passive chloride conductance (G Cl ) was analyzed in isolated toad skin. Comparatively low concentrations of CN− inhibited G Cl almost completely and fully reversibly, regardless of whether it was applied from the mucosal or serosal side. The IC50 was 180 ± 12 μm for voltage-activated G Cl and 305 ± 30 μm for the cAMP-inducted conductance. At [CN] 〈100 μm, the initial inhibition frequently declined partly in the continuous presence of CN−. Inhibition was independent of the presence of Ca2+. Inhibition was stronger at more alkaline pH, which suggests that dissociated CN− is the effective inhibitor. The onset of the inhibition of voltage-activated or cAMP-induced G Cl by CN− occurred with half-times of 34 ± 10 sec, whereas reversibility upon washout was twice as fast (18 ± 7 sec). If [CN−] 〈200 μm was applied under inactivating conditions (serosa −30 mV), the reduction of G Cl was stronger upon subsequent voltage-activation than under steady-state activated conditions. This effect was essentially complete less than 30 sec after apical addition of CN−, but G t recovered thereafter partially in the continuous presence of CN−. Dinitrophenol inhibited G Cl similarly, while omission of oxygen did not affect it. These observations, as well as the time course of inhibition and the full reversibility, suggest that interference of CN− with oxidative phosphorylation and subsequent metabolic depletion is not the reason for the inhibition of G Cl . We propose that the inhibition is directly on G Cl , presumably by competition with Cl− at a rate-limiting site in the pathway. Location and molecular nature of this site remain to be identified.
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