Background: Helicobacter pylori (Hp) infection and gastric atrophy are both risk factors for gastric cancer. Recently it has been found that X-ray examination for gastric cancer screening does not have much effect on the detection rate for gastric cancer in Japan. A candidate for a new mass screening for gastric cancer, the ABC method, using the combination assay of Hp and serum pepsinogen, was useful for identifying the development of gastric cancer in high-risk and low-risk populations.
View Article and Find Full Text PDFORL J Otorhinolaryngol Relat Spec
June 2010
In the stria vascularis (SV), it is known that the Na(+)-K(+)-ATPase is expressed abundantly and its activity in the basolateral membrane of marginal cells is high. Ouabain, an inhibitor of the Na(+)-K(+)-ATPase, causes not only a decline in the endocochlear DC potential but also acute vacuolar formation in marginal cells. We studied the ionic mechanisms underlying the ouabain-induced vacuolar formation in marginal cells using perilymphatic perfusion in guinea pigs.
View Article and Find Full Text PDFImmunoreactivity for the facilitated glucose transporter 1 (GLUT-1) has been found in the cochlear stria vascularis, but whether the strial marginal cells are immunopositive for GLUT-1 remains uncertain. To determine the cellular localization of GLUT-1 and to clarify the glucose pathway in the stria vascularis of rats and guinea pigs, immunohistochemistry was performed on sections, dissociated cells, and whole-tissue preparations. Immunoreactivity for GLUT-1 in sections was observed in the basal side of the strial tissue and in capillaries in both rats and guinea pigs.
View Article and Find Full Text PDFA large cervico-mediastinal tracheal defect in a 72-year-old man as a result of surgery for thyroid carcinoma with tracheal invasion and mediastinal lymph node metastasis was reconstructed using a pectoralis major myocutaneous flap and free costal cartilage grafts. The tracheal defect (55 mm x 30 mm) was located at the thoracic inlet adjacent to the major mediastinal vessels. Our reconstructive procedure was a two-staged surgery.
View Article and Find Full Text PDFORL J Otorhinolaryngol Relat Spec
September 2005
Osmotic diuretics are therapeutic agents used to reduce endolymphatic hydrops. However, glycerol-induced change in endolymph volume is followed by a rebound phenomenon. In this study, we investigated the rebound phenomenon occurring with isosorbide, an osmotic diuretic used as a therapeutic agent for Ménière's disease in Japan.
View Article and Find Full Text PDFObjective: Histamine may have physiologic functions in the inner ear. The locations of histamine receptors, however, have not yet been identified in the mammalian cochlea. The aim of this study was to investigate the localization of histamine receptor subtypes (H1, H2, and H3 receptors) in rat cochlea.
View Article and Find Full Text PDFObjectives: To present electrocochleographic findings in patients with autoimmune disease (AD) with sensorineural deafness (ADSD), and to discuss the etiologies of sensorineural hearing loss (SNHL) in cases of ADSD.
Methods: Study design is a retrospective review of electrocochleographic results of 26 patients with ADSD. To evaluate the electrocochleographic results, average SP/AP ratios were compared between ADSD and normal subjects.
The intercellular space in the stria vascularis (intrastrial space) is a closed space and isolated from both the endolymph and the perilymph in normal tissue. Loop diuretics such as bumetanide and furosemide cause an acute enlargement of the intrastrial space in association with a decline in the endocochlear potential. It is known that bumetanide inhibits the Na+-K+-2Cl- cotransporter, which is expressed abundantly in the basolateral membrane of marginal cells.
View Article and Find Full Text PDFIn the present study, two experiments were performed to investigate the influence of OPC-31260 on experimentally induced endolymphatic hydrops in guinea pigs and the regulation of aquaporin-2 (AQP2) mRNA expression in the rat inner ear. In morphological studies, the increases in the ratios of the length of Reissner's membrane (IR-L) and the cross-sectional area of the scala media (IR-S) were quantitatively assessed among normal guinea pigs (normal ears) and three groups with hydropic ears: hydropic ears with no infusion (non-infusion hydropic ears), hydropic ears with an infusion of physiological saline into the scala tympani (saline-infused hydropic ears) and hydropic ears with infusion of 0.3% OPC-31260 into the scala tympani (OPC-infused hydropic ears).
View Article and Find Full Text PDFCochlea endolymph, produced by the stria vascularis, is essential for normal inner ear function. Abnormal endolymphatic volumes correlate closely with pathological conditions such as Ménière's disease. The critical roles played by aquaporins, which facilitate osmotic movement of water molecules, are known in a variety of tissues.
View Article and Find Full Text PDFHistamine may have physiological functions in the inner ear. Histamine receptors, however, have not yet been identified in the mammalian cochlea. We determined, using reverse transcription polymerase chain reaction (RT-PCR), that H1, H2, and H3 histamine receptor mRNA is expressed in the rat cochlea.
View Article and Find Full Text PDFObjective: Loop diuretics such as bumetanide and furosemide cause an acute enlargement of the intrastrial space of the stria vascularis, with an associated decline in the endocochlear DC potential (EP). The aim of this study was to determine the role played by the Na+-K+-ATPase in the bumetanide-induced enlargement of the intrastrial space, and to examine the importance of the balance between the activities of the Na+-K+-2Cl- cotransporter and the Na+-K+-ATPase to the physiological function of the stria vascularis.
Material And Methods: Albino guinea pigs were used in experiments involving perilymphatic perfusion, EP measurement and electron microscopy.
The cochlear stria vascularis produces the endolymph and generates the endocochlear DC potential, two indispensable ingredients of an auditory transduction process. The marginal cell, one of the several cell types constituting the stria vascularis, is called 'the dark cell' on the basis of its appearance by transmission electron microscopy (TEM). To clarify whether this commonly observed 'dark appearance' is a normal characteristic of marginal cells, as conjectured in the literature, or an experimental artifact, we developed an in vivo fixation method for minimizing ischemic tissue damages.
View Article and Find Full Text PDFObjective: A change in the summating potential (SP) obtained from a patient with posterior fossa meningioma associated with surgical removal of the tumor was reported and possible mechanisms underlying the change are discussed.
Methods: This paper is a retrospective case review. A tertiary care referral center was the setting for the study.
Our previous studies have suggested a close relationship between vasopressin and endolymphatic hydrops, or the increased volume of endolymph in the inner ear. Endolymphatic hydrops is also thought to occur in Ménière's disease patients. In the kidney collecting duct, vasopressin induces the expression of aquaporin-2 (AQP2), resulting in increased water reabsorption.
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