1. Correlation between sagittal balance and thoracolumbar elastic energy parameters in 42 spines subject to spondylolisthesis or spinal stenosis and 21 normal spinesŠpela Bračun, Anna Romolo, Veronika Rehakova, Jure Leban, Žan Pukšič, Rok Vengust, Matej Daniel, Veronika Kralj-Iglič, Mitja Drab, 2024, izvirni znanstveni članek Povzetek: The curvature of the lumbar spine plays a critical role in maintaining spinal function, stability, weight distribution, and load transfer. We have developed a mathematical model of the lumbar spine curve by introducing a novel mechanism: minimization of the elastic bending energy of the spine with respect to two biomechanical parameters: dimensionless lumbosacral spinal curvature ▫$c_{LS}$▫ and dimensionless curvature increment along the spine CI. While most of the biomechanical studies focus on a particular segment of the spine, the distinction of the presented model is that it describes the shape of the thoracolumbar spine by considering it as a whole (non-locally) and thus includes interactions between the different spinal levels in a holistic approach. From radiographs, we have assessed standard geometrical parameters: lumbar lordosis LL, pelvic incidence PI, pelvic tilt PT, sacral slope ▫$\psi_0$▫ and sagittal balance parameter SB = sagittal vertical axis (SVA)/sacrumbicoxofemoral distance (SFD) of 42 patients with lumbar spinal stenosis (SS) or degenerative spondylolisthesis (SL) and 21 radiologically normal subjects. SB statistically significantly correlated with model parameters ▫$c_{L5}$▫ (r = − 0.34, p = 0.009) and − CI (r = 0.33, p = 0.012) but not with standard geometrical parameters. A statistically significant difference with sufficient statistical power between the patients and the normal groups was obtained for ▫$c_{LS}$▫ , CI, and SB but not for standard geometrical parameters. The model provides a possibility to predict changes in the thoracolumbar spine shape in surgery planning and in assessment of different spine pathologies.
Ključne besede: lumbar lordosis, thoracolumbar spine, elastic energy, sagittal balance, spine curvature
Objavljeno v DiRROS: 09.06.2026; Ogledov: 324; Prenosov: 313
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2. Decrease in cellular nanovesicles concentration in blood of athletes more than 15 hours after marathonZala Jeras, Mitja Drab, Damjana Drobne, Apolonija Bedina Zavec, Mojca Benčina, Barbara Drašler, Matej Hočevar, Judita Lea Krek, Ljubiša Pađen, Manca Pajnič, Neža Repar, Boštjan Šimunič, Roman Štukelj, Veronika Kralj-Iglič, 2021, izvirni znanstveni članek Povzetek: Introduction: Cellular nanovesicles (CNVs), that are shed from cells, have been recognized as promising indicators of health status. We analyzed the effect of long-distance running on concentration of CNVs, along with some standard blood parameters, in 27 athletes two days before and > 15 hours after physical effort. Methods: CNVs were isolated by repetitive centrifugation and washing of samples, and assessed by flow cytometry. Cholinesterase (ChE) and glutathione S-transferase (GST) activity were measured spectrophotometrically. Interleukin 6 (IL-6) and tumor necrosis factor-% (TNF-%) concentrations were measured using enzyme-linked immunosorbent assay (ELISA). C-reactive protein (CRP) was measured with immunoturbidimetric determination and lipidogram parameters were measured by enzymatic colorimetric assay. Flow cytometry was used for blood cell count and mean platelet volume (MPV) measurement. Results: More than 15 hours after physical effort a decrease was found in CNVs% concentration in isolates from blood (46%; p< 0.05), in ChE activity in whole blood (47%; p< 0.001), in plasma (34%; p< 0.01), and in erythrocyte suspension (54%; p< 0.001), as well as in GST activity in erythrocyte suspension (16%; p< 0.01) and in IL-6 concentration in plasma (63%; p< 0.05). We found no change in GST activity in plasma and in TNF-% concentration in plasma. Correlations (> 0.8; p< 0.001) between CNVs% concentration and ChE activity, and GST activity, respectively, in erythrocyte suspension were found. Conclusion: We found that > 15 hours post-physical effort, CNVs% concentration was below the initial value, concomitant with other measured parameters: ChE and GST activity as well as IL-6 concentration, indicating a favorable effect of physical effort on health status. CNVs% concentration and ChE activity in isolates from peripheral blood proved to have potential as indicators of the response of the human body to inflammation after physical effort. Physical activity should be considered as an important factor in preparation of subjects for blood sampling in procedures focusing on CNV-containing diagnostic and therapeutic compounds.
Ključne besede: membrane vesiculation, physical effort, blood samples, inflammation process, cellular nanovesicles, marathon
Objavljeno v DiRROS: 25.01.2021; Ogledov: 2816; Prenosov: 6741
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