Biomedical subjects

Péter Bogner

Publications and source records attributed to Péter Bogner.

6 recordsLinked to original sources

PubMed2005

Lithium induces phosphoglucomutase activity in various tissues of rats and in bipolar patients.

Phosphoglucomutase catalyses the reversible conversion of glucose-6-P and glucose-1-P. Lithium is a potent inhibitor of phosphoglucomutase in vitro, however, it is not known if phosphoglucomutase was significantly inhibited by Li+ in Li+-treated bipolar patients. Here, we demonstrate that phosphoglucomutase inhibition by chronic Li+ treatment causes alterations of glucose-phosphate levels in various tissues of rats. Also, phosphoglucomutase inhibition results in compensatory elevation of phosphoglucomutase activity in rat tissues and in leukocytes isolated from Li+-treated bipolar patients. The increase of uninhibited phosphoglucomutase activity in leukocytes of Li+-treated bipolar patients is due to the increased expression of the PGM1 gene.

Animals↗

PubMed2005

[Regulation of water transport in brain oedema].

The study gives an overview on the regulation of cerebral water content and of brain volume. The molecular mechanisms of the development and resolution of various oedema forms are discussed in detail. The physiological and pathophysiological role of the recently discovered molecular water channel proteins aquaporin-1 (AQP1) and aquaporin-4 (AQP4) as well as the importance of central neuroendocrine regulation by vasopressin and atriopeptin are reviewed based on the relevant literature and personal studies. Quantitative water maps based on the combination of multicompartment-T2, diffusion weighted MRI and T1 studies have proven to be powerful tools for studying new drugs against brain oedema brought about by various neuropathological conditions and for testing their efficacy both in animal experimental and clinical conditions. Non-peptide vasopressin antagonists, atriopeptin agonists and drugs targeting AQP4 are potential new families of oedema-decreasing drugs.

Animals↗

PubMed2004

[Virtual bronchoscopy for follow-up investigation of main airway stenoses].

The aim of the study was to compare the utility and effectivity of conventional and virtual bronchoscopy in the follow up of patients with main airway stenosis. 23 patients with trachea or main bronchi stenosis were enrolled in the study. The causes of the stenosis were malignant or benign tumor, struma and stent. The stenoses were evaluated before and after the different interventions (i.e. mechanical dilatation, laser photocoagulation, stent implantation, radiotherapy, chemotherapy or surgical resection.) The mean time between the first and second endoscopic and virtual bronchoscopic examinations was 140 days. The authors found good correlation between bronchofiberoscopy and virtual bronchoscopy findings. The data of virtual bronchoscopy were more exact. Based on this study the virtual bronchocopy can replace the traditional invasive method to follow-up patients with main airway stenosis.

Adult↗

PubMed2003

[Three-dimensional contrast-enhanced MR angiography].

INTRODUCTION: Three-dimensional contrast enhanced magnetic resonance angiography (3D CE MRA) is an increasingly important tool in modern noninvasive vascular imaging. MR angiography has rapidly advanced in the past few years making vascular imaging throughout the body safer and more accurate. AIM: The authors analyse the diagnostic and clinical value of the method based on their own experience and guidelines given by the literature. This article describes the basic technical principles of 3D CE MRA, and gives a short overview of the usefulness of this technique investigating vascular diseases. METHOD: Between August 17, 1999 and September 28, 2001 the authors performed eighty nine contrast-enhanced MR angiography with a 1.5 T scanner. Contrast material was administered intravenuosly with a power injector. The most frequent examinations included imaging of the aorta, supraaortic and renal arteries. RESULT: 82 technically successful angiography was performed. The images could not be evaluated due to poor quality in 5 cases and failure in 2 cases. MR angiographic images provided adequate spatial resolution within single breathhold. CONCLUSION: The time-of-flight and phase contrast MR angiographic techniques have been replaced in most vascular territories by the contrast-enhanced method. With future technical developments greater spatial and temporal resolution will become possible, thus increasing the usefulness of 3D CE MR angiography. In the near future this method of imaging will become the method of choice in the investigation of the arterial system, and in some special cases of the venous system.

Contrast Media↗

PubMed2002

[Spatial standardization of [15O]-butanol PET images using T1-weighted MRI data].

Population averaged brain activation studies require the spatial standardization of the individual perfusion PET images. This procedure is usually supported by T1-weighted MRI images. The authors developed a segmentation technique to improve the automatized transformation of the individual MRI images into Talairach space. It was for the first time in Hungary that population averages of standardized T1-weighted MRI and [15O]-butanol PET images of the brain were created after validation of the procedure using data from 23 healthy volunteers. The newly developed method offers a solution for the automatized processing of primary data from brain activation experiments prior to statistical analysis.

Adult↗

PubMed2002

[Effect of pathologic and induced peripheral vestibular balance disturbance on the central nervous system].

The authors investigated the central projection of excitement in acute stage vestibular neuronitis using positron emission tomography. The changes in the pattern of regional cerebral blood flow caused by the disease were compared with the effect of cold caloric stimulation known to provoke similar signs. It was concluded that the involved brain regions overlapped each other only partially. The mismatch could be explained by the compensatory processes developing during the disease. These processes do not normally develop during the caloric vestibular stimulation because of its short duration.

Adult↗