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  • 1
    Electronic Resource
    Electronic Resource
    Preparation and analysis of a volatile derivative of cysteic acid (1991)
    Springer
    Amino acids 1 (1991), S. 375-378 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Cysteic acid analysis ; Taurine analysis ; Gas chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have reported preparations and gas chromatographic analyses of volatile derivatives of sulfuric acid and taurine (Masuoka et al., 1988; 1989). By extending these studies, we have developed a method for the gas chromatographic determination of cysteic acid. Cysteic acid was converted to the N-isobutoxycarbonyl derivative by the reaction with isobutyl chloroformate in the presence of sodium hydroxide. After desalting with a cation-exchange column, the derivative was converted to the silver salt by reacting with silver oxide. The resulting silver salt was quantitatively esterified with methyl iodide in the presence of dimethyl sulfate and silver oxide. Dimethyl N-isobutoxy-carbonylcysteate [methyl 2-(N-isobutoxycarbonylamino)-3-(methoxysulfonyl) propanoate] formed was analyzed by gas chromatography. The calibration curve was linear up to 5.0µmol per ml of cysteic acid and the recovery was more than 95%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00814006
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  • 2
    Electronic Resource
    Electronic Resource
    Inhibition of sulfate excretion by (aminooxy)acetate induced stimulation of taurine excretion in rats (1995)
    Springer
    Amino acids 8 (1995), S. 345-352 
    Details
    ISSN: 1438-2199
    Keywords: Amino acids ; Cysteine metabolism ; Sulfate formation ; Taurine formation ; Hypotaurine ; Sulfur equilibrium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary l-Cysteine is mainly metabolized to sulfate and taurine through cysteinesulfinate pathway. Alternatively, sulfate is formed in rat liver mitochondria via 3-mercaptopyruvate pathway. Intraperitoneal administration of 5 mmol ofl-cysteine per kg of body weight resulted in the increase in sulfate and taurine (plus hypotaurine) excretion in the 24-h urine, which corresponded to 45.3 and 29.3%, respectively, ofl-cysteine administered. Subcutaneous injection of (aminooxy)acetate, a potent inhibitor of transaminases, together withl-cysteine halved the sulfate excretion and doubled the taurine excretion. In vitro sulfate formation froml-cysteine and froml-cysteinesulfinate in rat liver mitochondria was inhibited by (aminooxy)-acetate. The sulfate-forming activity of liver mitochondria obtained from rats injected with (aminooxy) acetate was also inhibited. These results indicate that the transamination reaction is crucial in sulfate formation and in the regulation of sulfur metabolism. Sulfur equilibrium in mammals was discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00806552
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  • 3
    Electronic Resource
    Electronic Resource
    Muon-catalyzed fusion in deuterium at 3 K (1996)
    Springer
    Hyperfine interactions 101-102 (1996), S. 21-28 
    Details
    ISSN: 1572-9540
    Keywords: muon-catalyzed fusion ; deuterium ; solid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Muon-catalyzed fusion in deuterium has traditionally been studied in gaseous and liquid targets. The TRIUMF solid hydrogen layer target system has been used to study the fusion reaction rates in the solid phase at a target temperature of 3 K. Both branches of the cycle were observed; neutrons by a liquid organic scintillator, and protons by a silicon detector located inside the target system. The effective molecular formation rate from the upper hyperfine state and the spin exchange rate have been measured, and information on the branching ratio parameters has been extracted.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02227602
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  • 4
    Electronic Resource
    Electronic Resource
    Characterization of solid hydrogen targets (1996)
    Springer
    Hyperfine interactions 101-102 (1996), S. 641-646 
    Details
    ISSN: 1572-9540
    Keywords: muon-catalyzed fusion ; thickness measurement ; solid hydrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In experiments using the TRIUMF solid hydrogen target system, the knowledge of the target thickness and uniformity is often essential in order to extract physical parameters from the data. We have characterized the thickness and uniformity of frozen targets using the energy loss of alpha particles. An accuracy of ∼5% was achieved, a limit imposed by the uncertainty in the stopping powers: The details of the method are described, and the thickness calibration of the target is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02227677
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  • 5
    Electronic Resource
    Electronic Resource
    Expressions of a calcium-binding protein (spot35/calbind in-D28k) in mouse olfactory cells: Possible relationship to neuronal differentiation (1997)
    Springer
    European archives of oto-rhino-laryngology and head & neck 254 (1997), S. 105-109 
    Details
    ISSN: 1434-4726
    Keywords: Immunohistochemistry ; Olfactory epithelium ; Cell growth ; Proliferating cell nuclear antigen ; Olfaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We used immunohistochemistry to investigate the expression of spot35/calbindin-D28k (calbindin) in mouse olfactory epithelium during development. Cell stages of immunopositive olfactory cells were determined by comparing the levels of proliferating cell nuclear antigen (PCNA). Calbindin-positive cells were abundant in the middle layer of the epithelium of animals before 2 weeks of age and gradually diminished during development. Only low levels were detectable near the basement membrane in the adult. Changes of calbindin-positive cells in terms of number and distribution were apparently compatible with localization changes of premature olfactory cells. PCNA overlapped calbindin in the nasal mucosa at lower magnifications on stained serial sections and immunohistochemical double staining revealed that calbindin-mmunoreactive cells were located mainly just above PCNA-immunoreactive cells in the basal layer of the epithelium. This indicated that calbindin is expressed postmitotically in immatureolfactory cells and is lost by mature cells. These findings suggest that calbindin might support the maturation of the olfactory cells, such as the projection of the neuronal processes, by stabilizing intracellular calcium ions in immature cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01526190
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  • 6
    Electronic Resource
    Electronic Resource
    Olfactory disturbances caused by the anti-cancer drug tegafur (1995)
    Springer
    European archives of oto-rhino-laryngology and head & neck 252 (1995), S. 48-52 
    Details
    ISSN: 1434-4726
    Keywords: Tegafur ; Bromodeoxyuridine ; Proliferating cell nuclear antigen ; Immunohistochemistry ; Cell mitoses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Olfactory disturbances induced by the anticancer drug tegafur were studied in separate clinical and experimental investigations. Five patients with olfactory dysfunction after tegafur were studied and were found to have normal endoscopic findings of the olfactory cleft mucosa. The average period for drug administration was 22 months. Recovery from the olfactory disturbance was poor and biopsy of the olfactory mucosa revealed severely degenerated epithelium. In experimental studies in a guinea pig animal model, effects of oral tegafur on mitotic cells in the olfactory epithelium were examined using bromodeoxyuridine (BrdU) uptake as index. At the conclusion of 3 weeks' treatment, no pronounced morphological changes were seen, but the number of BrdU-incorporating cells decreased in proportion to the dose of tegafur used. Following long-term administration of tegafur 18 months, mitotic cells reacting to BrdU or proliferating cell nuclear antigen had virtually disappeared, indicating persistent inhibition of mitotic cell activity. Morphological changes present included decreased olfactory cell numbers, loss of cells in areas just above basal cells and degeneration of the mucous layer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00171440
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  • 7
    Electronic Resource
    Electronic Resource
    Time-of-flight measurement of resonant molecular formation in muon-catalyzed dt fusion (1996)
    Springer
    Hyperfine interactions 101-102 (1996), S. 47-55 
    Details
    ISSN: 1572-9540
    Keywords: muon-catalyzed fusion ; muonic hydrogen ; muonic atoms ; muonic molecules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Preliminary results are reported for an experiment at TRIUMF where a time-of-flight technique was tested for measuring the energy dependence of the rate for muon-catalyzed dt fusion. Muonic tritium atoms were created following transfer of negative muons from muonic protium in a layer of solid hydrogen (protium) containing a small fraction of tritium. The atoms escaped from the solid layer via the Ramsauer-Townsend mechanism, traversed a drift region of 18 mm, and then struck an adjacent layer of deuterium, where the muonic atom could form a molecular system. The time of detection of a fusion product (neutron or alpha) following muon arrival is dependent upon the energy of the muonic tritium atom as it traverses the drift region. By comparison of the time distribution of fusion events with a prediction based on the theoretical energy dependence of the rate, the strength of resonant formation can in principle be determined. The results extracted so far are discussed and the limitations of the method are examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02227605
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