0000000000714396
AUTHOR
Ralph Feltens
showing 4 related works from this author
COX-2 expression in the guinea pig cochlea is partly altered by moderate sound exposure.
2006
The cyclooxygenase-2 isoform (COX-2) was found recently to be constitutively expressed in the guinea pig inner ear. To gain knowledge about its role in sound perception, alterations in the COX-2 level of moderate noise-stimulated cochleae were determined. Staining intensities were quantified in different regions using an immunohistochemical staining procedure and computer-assisted system. After 70 dB and 90 dB noise exposure for 1 h at 8000 Hz, COX-2 downregulation was observed in the organ of Corti, which was most prominent in Deiters' cells near Hensen cells and outer hair cells. In pillar cells, COX-2 levels were only slightly reduced after 70 dB but strongly diminished after 90 dB expos…
Analysis of differentially expressed proteins in oral squamous cell carcinoma by MALDI-TOF MS
2010
J Oral Pathol Med (2010) 40: 369–379 Purpose: To explore the presence of differentially expressed proteins in OSCC for discrimination of tumour and normal mucosa to establish potential biomarkers and therapeutic targets. Experimental Design: Paired protein samples of 12 individuals (tongue cancer and non-cancerous mucosa) were separated by two-dimensional polyacrylamid gel electrophoresis. The protein patterns were compared pairwise and protein spots were quantified. We identified about 70 regulated proteins which we subsequently identified by MALDI-TOF mass spectrometry. Results: Cancerous and non-cancerous tissues could be most precisely distinguished by a panel of proteins. They inclu…
Endothelial nitric oxide synthase upregulation in the guinea pig organ of Corti after acute noise trauma.
2004
Endothelial nitric oxide synthase (eNOS) upregulation was identified 60 h after acute noise trauma in morphologically intact cells of the reticular lamina in the organ of Corti of the guinea pig in the second turn of the cochlea. Using gold-coupled anti-eNOS antibodies and electron microscopy, it was shown that eNOS expression was upregulated in all cell areas and cell types except inner hair cells. Furthermore, eNOS was found in the organelle-free cytoplasm and in mitochondria of various cell types. The density of eNOS in mitochondria was considerably higher compared with the surrounding cytoplasm. Since eNOS activity is regulated by calcium, the eNOS detection was combined with calcium pr…
Mechanisms underlying noise-induced hearing loss
2006
Noise-induced hearing loss (NIHL) is the worldwide leading occupational disease and presents an important socio-economic factor. Despite numerous identified details about its etiology, the underlying mechanisms, which induce NIHL, have been only partially identified. In the present article, we shall discuss possible mechanisms focusing on failure in cellular calcium regulation, leading to a rise in mitochondrial NO production and reactive oxygen species formation. In cases where radical production is significantly elevated, pathological concentrations lead to alterations of cell physiological conditions and finally contribute to NIHL. A more detailed knowledge about the induction of free ra…