Faculty Hospital of Ostrava
Faculty Hospital of Ostrava
Cada R.,VSB - Technical University of Ostrava |
Frydrysek K.,VSB - Technical University of Ostrava |
Sejda F.,VSB - Technical University of Ostrava |
Demel J.,Faculty Hospital of Ostrava |
Pleva L.,University of Ostrava
Journal of Medical and Biological Engineering | Year: 2017
Paper focuses on biomechanics, specifically on locking cortical bone screws in angularly stable plates used for the treatment of bone fractures in the medical fields of traumatology and orthopaedics. During extraction of titanium-alloy implants, problems are encountered in an effort to loosen some locking bone screws from the locking holes of an angularly stable plate and the subsequent stripping of the internal hexagon of the screw head. The self-locking of the screw-plate threaded joint was verified by calculation and the effect of the angle of the thread on the head of the locking cortical bone screw on self-locking was evaluated. The magnitude of the torque, causing the stripping of the internal hexagon (the Inbus type head) of a locking cortical bone screw with a shank diameter of 3.5 mm from Ti6Al4 V titanium alloy to ISO 5832-3, was determined experimentally. Also, it was experimentally found that the rotation of the screwdriver end with a hexagonal tip inside the locking cortical bone screw head during stripping of the internal hexagon causes strain of the screw head perimeter and thereby an increase of thread friction. The effect of tightening torque on the possibility of loosening of the locking cortical bone screw from the locking hole of an angularly stable plate was assessed experimentally. From the evaluation of five alternative shapes of locking cortical bone screw heads in terms of the acting stress and generated strains, it follows that the best screw is the screw with the Torx type head, which demonstrates the lowest values of reduced stress and equivalent plastic strain. Based on experiments and simulations the authors recommend that all global producers of locking cortical bone screws for locking holes of angularly stable plates use the Torx type heads, and not heads of the Inbus type or the Square, PH, PZ types. © 2017, The Author(s).
Plevova P.,Faculty Hospital of Ostrava |
Plevova P.,Palacky University |
Cerna D.,Faculty Hospital of Ostrava |
Balcar A.,Faculty Hospital of Ostrava |
And 5 more authors.
Neoplasma | Year: 2010
Breast cancer associated with BRCA1 and BRCA2 gene mutations differs from non-BRCA tumors in several respects. We determined whether there was any difference in CCND1 (11q13) and ZNF217 (20q13) gene amplification with respect to BRCA status. Of 40 breast cancer samples examined, 15 and 9 were from BRCA1 and BRCA2 mutation carriers, respectively, and 16 from patients without mutation. Fluorescence in situ hybridization showed that eight tumors exhibited CCND1 amplification (20%; 3 BRCA1, 3 BRCA2, 2 non-BRCA). ZNF217 amplification was observed in three of 38 cases (8%; 2 BRCA1, 1 non-BRCA). There was no significant difference in CCND1 and ZNF217 amplification between BRCA1, BRCA2 and non- BRCA tumors. CCND1 amplification was associated with decreased disease-free (P = 0.045) and overall survival (P = 0.015). BRCA1 tumors with CCND1 amplification were estrogen receptor negative, in contrast to CCND1 amplified BRCA2 and non-BRCA tumors, suggesting that concurrent CCND1 amplification and estrogen and progesterone receptor negativity may predict germline BRCA1 gene mutation. All ZNF217 amplified tumors were of the medullary histological type (P = 0.002). There was no statistical correlation between CCND1 and ZNF217 amplification and estrogen receptor, progesterone receptor, and ERBB2 expression and TNM classification. CCND1 amplification did not correlate with EGFR expression.
Partila P.,VSB - Technical University of Ostrava |
Voznak M.,VSB - Technical University of Ostrava |
Peterek T.,VSB - Technical University of Ostrava |
Penhaker M.,VSB - Technical University of Ostrava |
And 4 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014
Emotional states of humans and their impact on physiological and neurological characteristics are discussed in this paper. This problem is the goal of many teams who have dealt with this topic. Nowadays, it is necessary to increase the accuracy of methods for obtaining information about correlations between emotional state and physiological changes. To be able to record these changes, we focused on two majority emotional states. Studied subjects were psychologically stimulated to neutral - calm and then to the stress state. Electrocardiography, Electroencephalography and blood pressure represented neurological and physiological samples that were collected during patient's stimulated conditions. Speech activity was recording during the patient was reading selected text. Feature extraction was calculated by speech processing operations. Classifier based on Gaussian Mixture Model was trained and tested using Mel-Frequency Cepstral Coefficients extracted from the patient's speech. All measurements were performed in a chamber with electromagnetic compatibility. The article discusses a method for determining the influence of stress emotional state on the human and his physiological and neurological changes. ©2014 SPIE.