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  • 1
    Electronic Resource
    Electronic Resource
    Mechanisms underlying taurine-mediated alterations in membrane function (1995)
    Springer
    Amino acids 8 (1995), S. 231-246 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Antioxidant ; Protein phosphorylation ; Phospholipid structure ; Calcium transport ; Phospholipid N-methyltransferase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Taurine mediates a plethora of membrane-linked effects in excitable tissues. To account for these multiple actions, four hypotheses have been proposed. One theory is based on the observation that taurine diminishes the inflammatory response of several cytotoxic oxidants. It is proposed that a reduction in the extent of membrane oxidative injury contributes to these cytoprotective actions. The second theory maintains that alterations in protein phosphorylation may underlie certain effects of taurine, particularly its effect on calcium transport. The third hypothesis assumes that the interaction of taurine with the neutral phospholipids leads to altered membrane calcium binding and function. The final theory ties the actions of taurine to inhibition of phospholipid N-methylation and the resulting changes in membrane composition and structure. While each of these hypotheses has merit, none of them can fully explain the membrane actions of taurine. Further studies are required to ascertain the importance of each theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00806821
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  • 2
    Electronic Resource
    Electronic Resource
    Shape and size changes induced by taurine depletion in neonatal cardiomyocytes (1998)
    Springer
    Amino acids 15 (1998), S. 135-142 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Osmoregulation ; Cell size ; Cell shape
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Taurine is a very important organic osmolyte in most adult cells. Because of this property it has been proposed that large changes in the intracellular content of taurine can osmotically stress the cell, causing changes in its size and shape. This hypothesis was examined by measuring cell dimensions of taurine deficient cardiomyocytes using confocal microscopy. Incubation of isolated neonatal rat myocytes with medium containing 5mMβ-alanine led to a 55% decrease in intracellular taurine content. Associated with the loss of taurine was a reduction in cell size. Two factors contributed to the change in cell size. First, there was a shift in cell shape, favoring the smaller of the two cellular configurations commonly found in the myocyte cell culture. Second, the size of the polyhedral configuration was reduced after ßalanine treatment. These same two events also contributed to size reduction in cardiomyocytes incubated with medium containing 30mM mannitol. Nonetheless, some qualitative differences exist between cells osmotically stressed by increasing the osmolality of the incubation medium and decreasing intracellular osmolality. The results support a role for taurine in the regulation of osmotic balance in the neonatal cardiomyocyte.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01345286
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  • 3
    Electronic Resource
    Electronic Resource
    Renal excretory responses of taurine-depleted rats to hypotonic and hypertonic saline infusion (1998)
    Springer
    Amino acids 15 (1998), S. 109-116 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Rat ; Natriuresis ; Hypotonic saline ; Hypertonic saline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Male Wistar-Kyoto rats were given either tap water (control) or 3%β-alanine (taurine-depleted) for three weeks. To prepare for the kidney function studies, the animals were then implanted with femoral vessels and bladder catheters. Two days after surgery, each rat was given an intravenous infusion of saline at the rate of 50μl/min and urine samples were collected at specific time intervals. An isotonic saline solution (0.9% NaCl) was infused for determination of baseline parameters and was followed by the infusion of a hypotonic saline solution (0.45% NaCl). Two days later, the infusion protocol was repeated in the same animals; however, a hypertonic saline solution (1.8% NaCl) was substituted for the hypotonic saline solution. Renal excretion of fluid and sodium increased in the control, but not taurine-depleted, rats during the hypotonic saline infusion. Interestingly, diuretic and natriuretic responses were similar between the groups during hypertonic saline infusion. The results suggest that taurine-depletion in rats affects renal excretory responses to a hypotonic, but not a hypertonic, saline solution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01345284
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  • 4
    Electronic Resource
    Electronic Resource
    Taurine prevents intracellular calcium overload during calcium paradox of cultured cardiomyocytes (1997)
    Springer
    Amino acids 13 (1997), S. 1-11 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Calcium paradox ; Cultured myocardial cell ; Intracellular free calcium ; Beating
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of taurine on the cellular distribution of [Ca2+]i, during the calcium paradox was examined by digital imaging of a single fura-2-loaded cell. Cardiomyocytes superfused with control medium containing 2mM Ca2+ exhibited typical transients associated with spontaneous beating. When the cells were exposed to Ca2+-free buffer, immediate cessation of both spontaneous contractions and calcium transients was observed as [Ca2+]; rapidly fell to a level of 3–6 × 10−8M. Subsequent restoration of medium calcium increased [Ca2+]i to level 4–7 times normal. Large increases in [Ca2+]i were observed in most cells and were associated with the development of contracture and bleb formation. Taurine pretreatment (20mM) caused no significant effect on [Ca2+]i during Ca2+ depletion. However, it inhibited excessive accumulation of [Ca2+]i during the Ca2+ repletion. Moreover, taurine treated cells recovered their Ca2+-transients and beating pattern earlier than non-treated cells. Finally morphological abnormalities commonly associated with calcium overload were attenuated by taurine treatment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01373044
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  • 5
    Electronic Resource
    Electronic Resource
    Interaction between taurine and angiotensin II: Modulation of calcium transport and myocardial contractile function (1997)
    Springer
    Amino acids 13 (1997), S. 105-114 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Taurine ; Angiotensin II ; α-Adrenergic agonists ; Na−-Ca2+ exchange ; Heart ; Contraction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Angiotensin II modulates several aspects of cardiac function, including myocardial contractility, heart rate and myocyte growth. Most of these actions are intimately associated with alterations in calcium transport. Since taurine also modulates calcium transport, we examined possible interactions between taurine and angiotensin II at the level of the major cellular extruder of calcium, the Na−-Ca2+ exchanger. Over a concentration range of 0.5–25 mM, Turne served as an effective inhibitor of angiotensin II-mediated stimulation of the exchanger. An Arrhenius plot of Na+-Ca2+ exchange activity revealed that angiotensin II (2 nM) increased transporter activity by reducing the activation energy of the transport process. Taurine (25 mM) inhibited the angiotensin II effect by partially preventing the reduction in activation energy. However, neither agent significantly altered the transition temperature, ruling out a change in membrane fluidity or an alteration in the rate limiting step of the transporter as a cause of the observed effects. Since the Na+-Ca2+ exchanger plays an important role in the handling of [Ca2+]i by the myocardium, the effect of taurine on angiotensin II's modulation of contractile function was also examined. Hearts perfused with buffer containing angiotensin 11 experienced a slight positive isotropic effect in the absence of taurine but this was converted to a negative inotropic effect in the presence of taurine. The data suggest that Turine inhibits some, but not all of the actions of angiotensin II. The possibility that a phosphorylation event is the site of the angiotensin II-taurine interaction is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01373209
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  • 6
    Electronic Resource
    Electronic Resource
    1-Aryl-1-heterosubstituierte λ5-Phosphorine durch Arylierung von λ3-Phosphorinen mit Aryldiazoniumsalzen in Gegenwart von Nucleophilen (1975)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 3271-3280 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 1-Aryl-1-hetero-substituted λ5-Phosphorins by Arylation of λ3-phosphorins with Aryldiazonium Salts in the Presence of Nucleophiles2,4,6-Trisubstituted λ3-phosphorins react in acetonitrile or dimethoxyethane with aryldiazonium tetrafluoroborates to give 1-aryl-1-fluoro-λ5-phosphorins 4 (Nu = F). In the presence of alcohols or phenols 1-alkyloxy (or 1-aryloxy)-1-aryl-λ5-phosphorins 4 (Nu = OR) are produced; in the presence of water 1,1′-oxybis(1-aryl-λ5-phosphorins) 10 are formed. The latter can also be transformed into 1-alkoxy(or 1-aryloxy-)-1-aryl-λ5-phosphorins 4 (Nu = OR) by nucleophilic displacement with alcohols or phenols. With alkanthiols in the presence of Lewis acids 1-alkylthio-1-aryl-λ5-phosphorins 11 (Nu = SR) are produced, which are inaccessible by the former method. The mechanism is discussed especially in connection with some unexpected products which were observed.
    Notes: Bei der Umsetzung von 2,4,6-trisubstituierten λ3-Phosphorinen mit Aryldiazonium-tetrafluoroboraten in Acetonitril oder Dimethoxyäthan entstehen 1-Aryl-1-fluor-λ5-phosphorine 4 (Nu = F). In Gegenwart von Alkoholen und Phenolen bilden sich 1-Alkoxy(bzw. 1-Aryloxy)-1-aryl-λ5-phosphorine 4 (Nu = OR), in Gegenwart von Wasser 1,1′-Oxybis(1-aryl-λ5-phosphorine) 10. Letztere können durch nucleophile Verdrängung mit Alkoholen oder Phenolen ebenfalls in 1-Alkoxy-(bzw. 1-Aryloxy)-1-aryl-λ5-phosphorine 4 (Nu = OR) übergeführt werden; mit Alkanthiolen in Gegenwart von Lewis-Säuren entstehen nach dem ersten Verfahren nicht zugängliche 1-Alkylthio-1-aryl-λ5-phosphorine 11 (Nu = SR). Der Mechanismus wird insbesondere im Zusammenhang mit einigen beobachteten, unerwarteten Reaktionsprodukten diskutiert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19751081017
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  • 7
    Electronic Resource
    Electronic Resource
    Arylierung von λ5-Phosphorinen mit Aryldiazoniumsalzen (1975)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 3281-3285 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Arylation of λ5-Phosphorins with Aryldiazonium Saltsλ5-Phosphorin derivatives with a phenyl residue at C-4 are arylated by aryldiazonium salts in benzene/methanol in the 4-phenyl ring with elimination of nitrogen: even when the aryl-residue at C-4 is substituted by a phenolic hydroxyl group arylation with elimination of the hydroxyl group and not azo coupling occurs. 2,4,6-Tri-tert-butyl-1,1-diphenoxy-λ5-phosphorin, however, reacts with an aryldiazonium salt by electrophilic replacement of the tert-butyl group at C-4 to give the arylazo dye of the λ5-phosphorin (20).
    Notes: λ5-Phosphorin-Derivate, die einen Phenylrest an C-4 tragen, werden durch Aryldiazoniumsalze in Benzol/Methanol unter Abspaltung von Stickstoff im 4-Phenylring aryliert; selbst wenn dieser Phenylrest an C-4 durch eine phenolische Hydroxylgruppe substituiert ist, tritt Arylierung unter Verdrängung der Hydroxylgruppe und nicht Azokupplung ein. 2,4,6-Tri-tert-butyl-1,1-diphenoxy-λ5-phosphorin dagegen kuppelt mit einem Aryldiazoniumsalz im Sinne einer elektrophilen Substitution unter Verdrängen der tert-Butylgruppe an C-4 zu dem Arylazofarbstoff des λ5-Phosphorins (20).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19751081018
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  • 8
    Electronic Resource
    Electronic Resource
    Bimolecular Formation of Radicals by H-Transfer, 6. Uncatalyzed Transfer Hydrogenation of a Benzhydryl Fluoride by 9,10-Dihydroanthracene (1994)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 557-563 
    Details
    ISSN: 0009-2940
    Keywords: Hydrogen transfer ; Molecule-induced radical formation ; Reduction of C—F bond ; 1-Adamantylfluorodiphenylmethane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Adamantylfluorodiphenylmethane (2) was reduced to 1-adamantyldiphenylmethane (3) when heated with 9,10-dihydroanthracene to 330°C. From the second-order kinetics, the activation parameters (ΔH
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19941270316
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  • 9
    Electronic Resource
    Electronic Resource
    Thermische Umlagerungen von 1-Allyloxy- und 1-Propargyloxy λ5-phosphorin-Derivaten (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 1752-1766 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thermal Rearrangements of 1-Allyloxy- and 1-Propargyloxy-λ5-phosphorin DerivativesThe thermal rearrangements of 1-allyloxy-λ5-phosphorin derivatives 1 affords - contrary to the formally similar Claisen rearrangement of allyl phenyl ethers - in the irreversible step an “anti-Woodward-Hoffmann” [3s5s] allyl shift to 4-allyl-1,4-dihydro-λ5-phosphorin derivatives 2. - The reaction is, as cross experiments prove, intramolecular and stereospecific according to 1st order law. It is accelerated by electron donating substituents in position 4 and by electron attracting substituent at the phosphorus, but is not much solvent-dependant. In a next step, again with allyl-inversion, a [3s3s] Cope rearrangement follows to give 2-allyl-1,2-dihydro-λ5-phosphorin derivatives 3. At somewhat higher temperature, by an intramolecular [4 + 2]-cycloaddition from 3j a tricyclus 4 is formed. Besides the experiments with deuterium marked compounds, the X-ray analysis of 4 proves the uniform stereochemic way of all these rearrangements. Steric and electronic influences on some analogous rearrangements are studied, the mechanism is discussed.
    Notes: Die thermische Umlagerung von 1-Allyloxy-λ5-phosphorin-Derivaten 1, führt im Gegensatz zu der formal ähnlichen Claisen-Umlagerung von Allylphenylethern im irreversiblen Primärschritt in einer“ anti-Woodward-Hoffmann”-[3s5s]-Allylwanderung zu 4-Allyl-1,4-dihydro-λ5-phosphorin-Derivaten 2. -Die Reaktion verläuft, wie Kreuzungsexperimente beweisen, intramolekular und stereospezifisch nach einer Reaktion 1. Ordnung. Sie wird durch elektronenabgebende Substituenten in R4 und elektronenanziehende substituenten am Phosphor gefördert, ist jedoch wenig löungsmittelabhängig. Ihr folgt in einem irreversiblen Schritt unter erneuter Allyl-Umkehr eine [3s3s]-Cope-Umlagerung zu 2-Allyl-1,2-dihydro-λ5-Phosphorin-Derivaten 3. Bei etwas höherer Temperatur gehen diese eine intramolekulare [4 + 2]-Cycloaddition zum Tricyclus 4 ein. Dessen Röntgenstrukturanalyse sowie die eindeutigen Deuterierungsergebnisse sprechen für einen stereochemisch einheitlichen verlauf der Umlagerungen. Sterische und elektronische Einflüsse auf einige analoge Umlagerungen werden untersucht, der Mechanismus wird diskutiert.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811140515
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  • 10
    Electronic Resource
    Electronic Resource
    Gleitringdichtungen für Kreiselpumpen der chemischen Industrie (1957)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 29 (1957), S. 241-249 
    Details
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Die Abdichtung der Wellendurchführung bei Kreiselpumpen für die chemische Industrie ist eine der wichtigsten Aufgaben des Pumpenkonstrukteurs. Die Gleitringdichtung wird immer mehr verwendet und wird in den verschiedensten Ausführungen hergestellt. An die Oberflächenglätte der beiden aufeinander gleitenden Dichtringe werden besondere Anforderungen gestellt. Die Unebenheiten an der gleitenden Oberfläche sollen unter 1 μ sein. Es wird versucht, die inneren Vorgänge der Druckentspannung zwischen den beiden Gleitringen zu erklären. Die Werkstoffe für Gleitringdichtungen, speziell für korrodierende Medien, werden besprochen, zulässige Drucke und Temperaturen werden angegeben.
    Additional Material: 21 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330290403
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