Publications by authors named "Leszek Wojnar"

In the present paper, a procedure is developed for fully automatic recognition of the frontal sinus in cranial radiographs. An X-ray image of a whole skull is required at the input of the procedure, which consists of three subsequent steps: the selection of a rectangular region of interest, containing the sinus; detection of the line of brow ridges; and fronto-nasal suture, detection of the borders of the frontal sinus. The recognition algorithm is based on a method of connectivity-preserving thresholding, introduced in the present study, and on watersheds from markers.

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Tgalphaq44 mice with targeted overexpression of activated Galphaq protein in cardiomyocytes mimic many of the phenotypic characteristics of dilated cardiomyopathy in humans. However, it is not known whether the phenotype of Tgalphaq44 mice would also involve dysfunction of cardiac mitochondria. The aim of the present work was to examine changes in EPR signals of semiquinones and iron in Fe-S clusters, as compared to classical biochemical indices of mitochondrial function in hearts from Tgalphaq44 mice in relation to the progression of heart failure.

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Objective: The aim of the present work was to analyze coronary endothelial function in the transgenic mouse model of dilated cardiomyopathy (Tgalphaq*44 mice).

Methods: Coronary vasodilatation, both NO-dependent (induced by bradykinin) and PGI(2)-dependent (induced by acetylcholine), was assessed in the isolated hearts of Tgalphaq*44 and FVB mice. Cardiac function was analyzed in vivo (MRI).

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The objective of this study was to evaluate potential anti-atherogenic properties of hen eggs enriched naturally with conjugated linoleic acid (CLA) isomers (cis-9, trans-11 and trans-10, cis-12). Eighteen apoE and LDL receptor double-knockout mice (apoE/LDLR- / - ), at the age of 4 months with pre-established atherosclerosis, were randomly assigned to three experimental groups (n 6) and fed AIN-93G-based diets for the next 2 months. The experimental diets were: AIN-93G+ CLA-free egg-yolk powder (control); AIN-93G+ CLA-free egg-yolk powder +0.

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Treatment of yeast Saccharomyces cerevisiae with alpha-pheromone has been reported to lead to massive apoptosis of cells finding no conjugation partner [Severin FF, Hyman AA. Pheromone induces programmed cell death in S. cerevisiae.

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Visual assessment of the endocardial outline is too subjective and the results do not provide enough support for reliable analysis. The main problem that hinders echocardiographic diagnosis in measurements of ventricular size and shape during subsequent cycles of cardiac function lies in difficulties in obtaining precise delineation of endocardial margins. A new, semiautomatic algorithm for tracing endocardial outlines of newborns that were detectable in echocardiographic images is presented.

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Synopsis of recent research by authors named "Leszek Wojnar"

  • - Leszek Wojnar's research primarily focuses on advanced biomedical imaging techniques and cardiac dysfunction analysis, with notable contributions to the automatic recognition of anatomical structures in X-ray images and echocardiographic assessment in pediatric cardiology.
  • - His studies include the investigation of mitochondrial dysfunction in models of dilated cardiomyopathy, utilizing electron paramagnetic resonance (EPR) techniques to assess mitochondrial signals and correlate them with heart failure progression.
  • - Wojnar also explores the impact of dietary factors, such as conjugated linoleic acid from enriched eggs, on atherosclerosis development, demonstrating a potential relationship between nutrition and cardiovascular health in genetically modified mouse models.