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  • 1
    ISSN: 1433-0458
    Keywords: Schlüsselwörter Mukoviszidose ; Zystische Fibrose ; Menschliches Nasalepithel ; Epithelialer Na+-Kanal ; Cl ; -Sekretion ; Key words Cystic fibrosis ; Human nasal epithelium ; Epithelial Na+ channels ; Cystic fibrosis transmembrane conductance regulator ; Cl ; secretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Cystic fibrosis (CF) is the most commonly inherited disease in Caucasians and is caused by a mutation in the gene encoding a membrane transport protein. This cystic fibrosis transmembrane conductance regulator (CFTR) is thought to be an apical Cl– channel activated by intracellular cAMP. Most recent findings suggest that CFTR is more than a pure Cl– channel and might be involved in the regulation of other transport systems. In the present study we show that CFTR as a Cl– channel plays only a minor role in primary cultured human nasal epithelium derived from non-CF and CF patients. These findings are especially of interest for non-CF human nasal epithelia in which CFTR is correctly inserted. In both tissues Cl– secretion is negligible as compared with Na+ absorption. We confirm and expand our previous observations that Na+ absorption in human nasal epithelium is the dominant ion transport process and that Cl– secretion is detectable in both CF and non-CF tissue. Moreover, we show that cAMP and ATP were not able to stimulate any silent Cl– channels in CF or non-CF human nasal epithelial cells. We further give evidence that in human nasal CF and non-CF epithelium Na+ absorption is mediated by epithelial Na+ channels (ENaC) that are either different from those of other epithelia or which exhibit altered regulation. These differences between Na+ channels of human nasal epithelium and ”classical” epithelial Na+ channels include lack of activation by the intracellular second messenger cAMP and the steroid hormone aldosterone. We show further that human nasal Na+ channels are inhibited by Cl–-channel blockers and exhibit a different pharmacology towards common Na+ channel blockers.
    Notes: Zusammenfassung Mukoviszidose [zystische Fibrose (CF)] ist die häufigste Erbkrankheit in der kaukasischen Bevölkerung. Sie wird hervorgerufen durch Mutation eines Gens, welches für ein membranständiges Transportprotein kodiert, den „cystic fibrosis transmembrane conductance regulator” (CFTR). Dieser CFTR ist in der apikalen Membran von Epithelzellen lokalisiert und fungiert dort als cAMP-aktivierbarer Cl–-Kanal. Neuere Untersuchungen haben ergeben, daß der CFTR mehr als ein normaler Cl–-Kanal ist und wahrscheinlich in die Regulation einer Reihe weiterer Transportsysteme involviert ist. In dieser Studie zeigen wir, daß der CFTR in seiner Rolle als Cl–-Kanal nur eine untergeordnete Rolle in primärkultivierten menschlichen Nasenepithelzellen von CF- und Nicht-CF-Patienten spielt. Dieses Ergebnis ist besonders für das Nasenepithel von Nicht-CF-Patienten erstaunlich, da hier der CFTR korrekt eingebaut wird. In beiden Geweben spielt also eine Cl–-Sekretion verglichen mit der Na+-Absorption eine vergleichsweise geringe Rolle. Wir bestätigen mit dieser Untersuchung unsere früheren Beobachtungen, daß im menschlichen Nasenepithel Na+-Absorption der dominierende Ionentransportprozeß ist und eine Cl–-Sekretion weder in CF- noch in Nicht- CF-Geweben in relevantem Maße vorhanden ist. Zudem zeigen wir, daß weder cAMP noch ATP irgendeine Cl–-Sekretion in CF- oder Nicht-CF-Nasenepithelzellen stimulieren können. Desweiteren ergaben sich Hinweise darauf, daß sich die epithelialen Na+-Kanäle (ENaC) im Nasenepithel, welche für einen Teil der Na+-Absorption zuständig sind, von den epithelialen Na+-Kanälen in anderen Geweben unterscheiden. Diese Unterschiede zwischen den Na+-Kanälen im menschlichen Nasenepithel und den „klassischen” epithelialen Na+-Kanälen bestehen einerseits in ihrer fehlenden Aktivierbarkeit durch den intrazellulären Botenstoff cAMP und das Steroidhormon Aldosteron. Wir zeigen weiterhin, daß menschliche nasale Na+-Kanäle durch Cl–-Kanal-Blocker gehemmt werden können und eine andere Pharmakologie auf gebräuchliche Na+-Kanal-Blocker aufweisen.
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  • 2
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 3
    ISSN: 1434-4726
    Keywords: Tubal function ; Craniofacial morphology ; Deglutition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 26 children without hearing impairment have been examined by otolaryngologists and orthodontists. According to the tubal function test in a pressure chamber they were classified into a group with good and poor tubal function. The E.N.T. examination was unconclusive for a possible relationship between rhinological findings, mode of breathing, sinusitis, size of tonsils, nasal airway resistance and tubal function. Adenoids proved to be a mechanical impairment for active tubal function as stated by many authors. The cephalometric analysis of lateral head films combined with a static and dynamic-functional evaluation of tongue posture revealed significant differences between children with good and poor tubal function. Subjects with a vertical craniofacial growth pattern seem to be predisposed for poor tubal function. Analysing static tongue posture in children with poor tubal function the tongue lies more retracted in a backward position. The back of the tongue is flattened in relation to the palatal arch. In children with good tubal function there is a much closer contact between the back of tongue and the hard palate. Subjects with poor tubal function have an increased incidence of abnormal deglutition combined with tongue-thrust, teeth-apart swallowing, lack of sealing off the anterior oral cavity and contraction of the circumoral musculature. In children with good tubal function one can find the somatic type of swallowing that means no contractions of the circumoral muscles, no tongue-thrust during deglutition but contact of the molars and contraction of the masseter muscle.
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  • 4
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1208 patients with secretory otitis media were treated and followed over a ten year period. The treatment consisted of adenoidectomy in 630 children and 1473 middle ear ventilation tubes in 578 patients in whom adenoidectomy and conservative measurements proved not to be successful. Conductive hearing loss in children with enlarged adenoids is caused by accumulation of fluid in the middle ear in more than 90%. Adenoidectomy per se improves hearing in 75%. In the remaining 25%, where ventilating tubes are indicated, recurrency rates of more than 30% are observed with prolonged follow up. Therefore a control-period of 2 years is necessary. Complications may include infection (10%), seldom, however, persistant perforations and very rarely secondary cholesteatoma.
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  • 5
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Endoscopy of the pharyngeal tubal orifice combined with tubal function tests revealed new information about the pathophysiology of the eustachian tube. Active tubal openings without swallowing, mediated trough isolated levator and tensor contractions are demonstrated. The interaction of adenoids and impaired tubal function is shown in three children. In patients with patulous tubes, the morphology of the tubal toruses and the functional pattern of the cartilage rotation are analysed.
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  • 6
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 7
    ISSN: 1434-4726
    Keywords: Autodynamic controlled flash exposure in microphotography ; TTL-computer flash ; Operating microscope OPMI I ; Operationsmikroskop OPMI I ; TTL-Computerblitzsystem ; Automatische Belichtung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das autodynamisch meßgeregelte TTL-Computerblitzsystem kann nach relativ einfachen Umbauten am OPMI I verwendet werden. Auch beim Einsatz am Mikroskop erweist sich das TTL-Computerblitzsystem für automatische Belichtung von Vorteil. Im wesentlichen werden eine Vereinfachung und Qualitätsoptimierung der Photodokumentation mit dem Operationsmikroskop erzielt. Die Kostenersparnis durch Verwendung derselben Beleuchtungs- und Blitzanlage für Endoskopie und Mikroskopie sind evident.
    Notes: Summary The autodynamic controlled TTL-computer flash (TTL= through the lens) with combined cold light fountain was adapted to the operating microscope OPMI I. The TTL-computer flash system facilitates the handling of the photomicroscope and provides accurately exposed photos in microphotography.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 9
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Beurteilung der Tubenfunktion bei einer Untersuchung in der Druckkammer erfolgt normalerweise aufgrund subjektiver Empfindungen der untersuchten Personen. Eine Registrierung der Trommelfellbewegungen während Druckänderungen in der Druckkammer kann our erfolgen, wenn auch im abgeschlossenen Gehorgang der Druck laufend an den der Umgebung angeglichen wird. In einem ncuartigen Differentialmanometer bewirken spezielle Ausgleichsöffnungen, daß nur Druckanderungen im Gehörgang durch schnelle Trommelfellbewegungen erfaßt werden, jedoch keine Druckschwankungen, die bei der Änderung des Außendruckes oder durch die langsame Ausbuchtung des Trommelfells während dieser Druckänderung entstehen. Die Registrierung einer schnellen Trommelfellbewegung als Ausschlag auf einem Schreibgerät zeigt eine Tubenöffnung an, die zu einem Druckausgleich zwischen Mittelohr und Umgebung geführt hat. Die beschriebene neue Methode ermöglicht eine quantitative Feststellung der Fähigkeit der Ohrtrompete, für einen regelmäßigen Druckausgleich zwischen Mittelohr und Umgebung bei kontinuierlich verändertem Außendruck zu sorgen. In allen Fallen mit intaktem beweglichem Trommelfell führt sic zu objektiven und reproduzierbaren Ergebnissen.
    Notes: Summary The assessment of tubal function in a hyperbaric chamber is usually based on the sensations experienced by the subjects so examined. The registration of tympanic-membrane movements during pressure changes in the chamber requires that the pressure in the ear canal, occluded by the recording instrument, is continually equalised to that in the ambient air. A differential manometer is described that, owing to the action of a low-frequency bypass, is only sensitive to quick drum movements, but not to slow changes in ambient air pressure or those due to slowly-occurring displacements of the tympanic membrane. These quick drum movements are indicative of pressure equilibrations between the outside air and that in the middle ear and are caused by a momentary opening of the Eustachian tube. This new method facilitates a quantitative determination of Eustachian-tube action when equilibrating the differential pressure across the tympanic membrane while the ambient pressure is being altered. In all cases with mobile, intact tympanic membranes reproducible and objective results were obtained.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1434-4726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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