Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Chemistry  (5)
  • Coproporphyrinogen oxidase  (1)
  • Guinea pigs  (1)
  • Key words: Leukotriene — Allergic rhinitis — Guinea pig models — Total airway resistance — Nasal symptoms  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Effects of a cysteinyl leukotriene antagonist, ONO-1078 (pranlukast), on total airway resistance after antigen challenge in sensitized guinea pigs (1997)
    Springer
    Inflammation research 46 (1997), S. 143-146 
    Details
    ISSN: 1420-908X
    Keywords: Key words: Leukotriene — Allergic rhinitis — Guinea pig models — Total airway resistance — Nasal symptoms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Objective and Design: To define the role of leukotriene (LT) in allergic rhinitis, we examined the effects of a cysteinyl (Cys) LT antagonist (ONO-1078, pranlukast).¶Material: Actively sensitized Dunkin-Hartley guinea pigs.¶Treatment: ONO-1078 (pranlukast), 3–100 mg/kg p.o. l h before antigen challenge.¶Methods: Nasal symptoms (sneezing, nasal scratches), changes of total airway resistance (TAR by plethysmography) and eosinophil infiltration into the nasal mucosa were determined following topical antigen (OA) challenge. Dunnet's test (TAR and symptoms) and the Mann-Whitney U-test (eosinophils) were applied.¶Results: Control animals showed bi-phasic nasal responses, peaking 10 min and 240 min after the topical antigen challenge, respectively. While the early-phase response was characterized by nasal symptoms of sneezing and scratching accompanied by the increase in TAR, the late-phase was characterized by an increase in TAR accompanied by eosinophil infiltration into nasal mucosa. The nasal symptoms (sneezing and scratching) were not inhibited by pretreatment with ONO-1078 at doses up to 100 mg/kg (p.o., n = 15). Although early peak responses of TAR were not affected with even the highest dose (30 mg/kg, p.o., n = 6), late-phase TAR peak response (control: 174.8 ± 8.2%, n = 6) were significantly inhibited by 10 mg/kg (142.7 ± 15.8%; p 〈 0.05, n = 6) and 30 mg/kg (118.0 ± 6.6%; p 〈 0.01, n = 6) of ONO-1078 (p.o.). In addition, the eosinophil infiltration induced by the antigen was not inhibited by ONO-1078 (30 and 100 mg/kg, p.o., n = 6).¶Conclusions: Our results suggest that Cys LT may play an important role in the late-phase increase in TAR in the guinea pig model of allergic rhinitis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000110050538
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Oxidation of protoporphyrinogen IX in Escherichia coli is mediated by the aerobic coproporphyrinogen oxidase (1999)
    Springer
    Molecular genetics and genomics 261 (1999), S. 1012-1020 
    Details
    ISSN: 1617-4623
    Keywords: Key words Porphyrin biosynthesis ; Protoporphyrinogen oxidase ; Coproporphyrinogen oxidase ; Overexpression ; Enzymatic conversion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoporphyrinogen oxidase, the penultimate enzyme involved in the biosynthetic pathway for heme, catalyzes the removal of six electrons from protoporphyrinogen IX to generate protoporphyrin IX. In Escherichia coli, this enzyme is encoded by the hemG gene. In this study we examined possible alternate pathways for the oxidation of protoporphyrinogen IX to protoporphyrin IX, by isolating and investigating E. coli mutants that can still grow normally when the hemG gene is disrupted. One of these mutants was characterized in detail and had a mutation in the promoter region of the hemF gene, which encodes aerobic coproporphyrinogen oxidase, the enzyme involved in the step immediately before protoporphyrinogen oxidase. Measurement of the promoter activity of the hemF gene showed that the level of transcription was elevated by the mutation. Overexpression of a wild-type hemF gene cloned in a multicopy plasmid also restored the growth of ΔhemG strain. Extracts from cells that overexpress hemF exhibited an increased ability to oxidize protoporphyrinogen IX to protoporphyrin IX. These findings suggest that the E. coli aerobic coproporphyrinogen oxidase has an intrinsic capacity to oxidize not only coproporphyrinogen III but also protoporphyrinogen IX.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004380051050
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Changes in nasal airway resistance and secretory response in the guinea pig after nasal challenge with capsaicin and histamine (1994)
    Springer
    European archives of oto-rhino-laryngology and head & neck 251 (1994), S. 224-228 
    Details
    ISSN: 1434-4726
    Keywords: Capsaicin ; Histamine ; Nasal airway resistance ; Nasal secretion ; Guinea pigs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We studied serial changes of nasal airway resistance (NAR) and secretory response after topical stimulation with either capsaicin or histamine, since both are known to stimulate a chemosensitive sensory C-fiber ending. After topical capsaicin stimulation, a dose-related increase of NAR was noted, with a peak response occurring at 10–20 min. These NAR responses were completely abolished following systemic pretreatment with capsaicin. However, they were not affected by atropine, diphenhydramine or hexamethonium pretreatment. After topical histamine stimulation, an atropine-resistant increase of NAR was found and continued more than 120 min. The early phase of this response was significantly suppressed by the systemic pretreatment with capsaicin. A secretory response also occurred after topical capsaicin stimulation and continued for 30 min. This secretory response was almost completely blocked by atropine, hexamethonium or systemic capsaicin pretreatment and was partially suppressed by diphenhydramine pretreatment. These findings suggest that sensory C-fiber stimulation can induce both atropine-resistant vascular reflexes and atropine-sensitive secretory reflexes, and that these reflexes might play an important role during the early phase after nasal stimulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00628428
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Infrared spectrum of polyvinylidene chloride. II (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 37 (1959), S. 263-271 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to complete the more advanced assignments of the bands in the spectrum of polyvinylidene chloride, we prepared deuterated polyvinylidene chloride and obtained its spectrum. With the assumption that frequencies of the skeletal stretching modes and the CCl2-stretching modes cannot change drastically by deuteration, we have achieved the following assignments. Since the frequencies of the bands at 516, 527, 565, 580, 600, and 655 cm.-1 did not change largely by deuteration, they are assigned to the CCl2-stretching modes. We can assign the crystallization sensitive band at 753 cm.-1 to the CH2-rocking mode, because it was shifted to 607 cm.-1 by deuteration. The other crystallization sensitive band at 884 cm. -1, which was shifted to 822 cm.-1 by deuteration, is assigned to the skeletal stretching mode. From the frequency changes by deuteration, we could conclude that our previously reported assignments of the bands at 1046, 1071, 1357, 1407, 2966, and 3010 cm. -1 are reasonable.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203713120
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Infrared spectrum of polyvinylidene chloride. I (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 37 (1959), S. 251-261 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to assign the infrared spectrum of polyvinylidene chloride, we studied the properties of the bands in the spectrum of this polymer and the spectrum of polyvinylidene bromide. We found that many bands disappeared or became weak in the region of 400 to 700 cm.-1, when polyvinylidene chloride was molten. From the relation between the absorption intesities and the density of the polymer, we could prove that the two bands at 753 and 884 cm.-1 are crystallization-sensitive bands. The doubt at 1046 and 1071 cm.-1 in the spectrum of polyvinylidene chloride showed an interesting behavior, i.e., one component at 1046 cm.-1 appeared more strongly than the other at 1071 cm.-1 in the spectrum of the unstretched sample, and their intensity relation was inversed by stretching the sample. The infrared spectrum of polyvinylidene bromide resembled very well to the spectrum of polyvinylidene chloride. We assigned several bands in the spectrum of polyvinylidene chloride from their polarizations and spectral regions, i.e., the doublet at 1046 and 1071 cm.-1 is assigned to the skeletal stretching mode, the parallel brand at 1357 cm.-1 to the CH2--wagging mode, the perpendicular band at 1407 cm.-1 to the CH2--bending mode, the band at 2966 cm. -1 to the CH2-symmetric stretching mode, and the band at 3010 cm.-1 to the CH2-antisymmetric stretching mode.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203713119
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Infrared spectrum of polyvinyl chloride. I (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 37 (1959), S. 273-280 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to assign the infrared spectrum of polyvinyl chloride, we obtained the polarized infrared spectra of polyvinyl chloride, the spectral changes of the molten sample, and the infrared spectrum of polyvinyl bromide. The polarized infrared spectra of polyvinyl chloride which we had obtained showed satisfactory agreement with previous reports. The infrared spectra of polyvinyl chloride and polyvinyl bromide resembled each other. From the frequency defferences of the corresponding bands of both polymers, we assigned the bands at 690, 635, and 615 cm.-1 to the C—Cl-stretching modes in the spectrum of polyvinyl chloride. We found four bands in the CH- and CH2-stretching region of polyvinyl chloride as Krimm and Liang stated in their paper.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203713121
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Infrared spectrum of polyvinyl chloride. II (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 37 (1959), S. 281-294 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to assign the CH, CH2-vibration modes and the skeletal modes in the spectrum of polyvinyl chloride, we obtained deuterated polyvinyl chloride and the infrared spectrum of it, and we assumed that frequencies of the skeletal modes and the C-Cl stretching modes may not change drastically by deuteration. The frequencies of the bands of polyvinyl chloride at 1428, 1333, and 1255 cm.-1 were largely shifted by deuteration and we assign the 1428 cm.-1 band to the CH2-bending mode and the bands at 1333 and 1255 cm.-1 to the CH-deformation modes. As the frequency of the band at 1094 cm.-1 was not largely shifted, we assign it to the skeletal stretching mode. As the band at 969 cm.-1 separated into two components at 937 and 787 cm.-1 by deuteration, we believe that this band consists of two overlapped bands, one caused by the skeletal stretching mode and the other by the CH2-rocking mode. Both the band of polyvinyl chloride at 837 cm.-1 and the band of the deuterated polymer at 806 cm.-1 disappear when they are molten. We think these two bands correspond to each other and assigned them to the skeletal stretching modes.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203713122
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Infrared spectra of vinylidene chloride-vinyl chloride copolymer (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 36 (1959), S. 389-405 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Observation of the infrared spectra of vinylidene chloride and vinyl chloride copolymers permitted clarification of some points which were rather ambiguous from the study of the homopolymers, and gave some information on the bands of the copolymers. In particular, the band at 868 cm.-1, which had been considered to be that of polyvinylidene chloride, was observed only in the copolymer. Depending on the mode of arrangement of vinylidene chloride and vinyl chloride in the copolymer, the CH-deformation frequency appears at 1206, 1245, or 1255 cm.-1. The same behavior was observed with vinylidene chloride-vinyl bromide copolymers. With the copolymer rich in vinylidene chloride, the band at 1206 cm.-1 can be used for determination of vinyl chloride content. In deuterated vinylidene chloride-vinyl chloride copolymer, the CD2-bending frequency due to the —CDCl—CD2—CCl2—sequence appears at 1081 cm.-1.
    Additional Material: 27 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203613033
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...