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C Mittermayer

Publications and source records attributed to C Mittermayer.

At least 253 records · Page 14Linked to original sources

Induction of human vascular endothelial stress fibres by fluid shear stress.

Endothelial cells of the arterial vascular system and the heart contain straight actin filament bundles, of which there are few, if any, in the venous endothelium. Since stress fibre-containing endothelial cells within the vascular system tend to be located at sites exposed to particularly high shear stress of blood flow, we have investigated, in an experimental rheological system (Fig. 1), the response of the endothelial actin filament skeleton to controlled levels of fluid shear stress. Here we report that endothelial stress fibres can be induced by a 3-h exposure of confluent monolayer cultures of human vascular endothelium to a fluid shear stress of 2 dynes cm-2, approximately the stress occurring in human arteries in vivo. Fourfold lower levels of shear stress that normally occur only in veins, had no significant effect on the endothelial actin filament system. The formation of endothelial stress fibres in response to critical levels of fluid shear stress is probably a functionally important mechanism that protects the endothelium from hydrodynamic injury and detachment.

Actinin↗

Idiopathic calcinosis of the scrotum: scanning electron microscopic study with X-ray microanalysis.

In a 31-year-old man 12 nodules up to 1 cm in diameter were observed in the scrotum; these had developed over 3 years. Energy-dispersive x-ray analysis of the dermal foci showed a high content of calcium and phosphorus even in nodules smaller than 1 mm in diameter. No increased mineral deposition was observed in the surrounding connective tissue, however. Scanning electron microscopy revealed finely granulated crystals, and cellular remnants giving rise to development of calcified nodules were disclosed. The results support the hypothesis of a degenerative origin of scrotal calcinosis.

Adult↗

Absence of epidermal growth factor receptor expression in squamous cell carcinoma of the uterine cervix is an indicator of limited tumor disease.

The expression of growth factors is considered as an important diagnostic and prognostic feature in tumor pathology. We investigated the value of the immunohistochemical EGF-receptor expression (EGF-R) in 30 squamous cell carcinomas of the uterine cervix, treated by radical hysterectomy and lymphadenectomy according to the Wertheim-Meigs-Okabayashi technique. Immunohistochemical reactions were performed on 4 microm sections from paraffin-embedded tissue, using an indirect peroxidase method. The staining results were evaluated semiquantitatively as negative (n=9; 30%) or as slightly, moderately or severely positive (n=21; 70%). The EGF-R-negative tumors were found in less advanced tumor stages. None had invaded into the parametrium (100%), eight were staged as T1 (89%), seven as N0 (78%), and seven showed no evidence for lymphangiosis carcinomatosa (78%). The respective values for the EGF-R-positive tumors ranged from 52% to 67%. However, only the difference in parametral invasion (EGF-R-negative: 0%, EGF-R-positive: 38%) was statistically significant (p=0.0306), probably due to the small number of cases. The EGF-R-expression was not correlated to histomorphological tumor grading. The results of this study indicate an inverse correlation between EGF-R expression and tumor spread. Assuming that this trend could be confirmed by a larger group of patients, immunostaining for EGF-R in a tumor biopsy could be useful to adapt surgical strategies and adjuvant therapy in the individual patient. Moreover, the EGF-R is an interesting target for immunotherapeutic approaches in squamous cell cervical carcinoma.

Adult↗