Lege Artis Medicinae

[Systemic diseases in pseudoexfoliation syndrome]

HOLLÓ Gábor

SEPTEMBER 20, 2012

Lege Artis Medicinae - 2012;22(08-09)

[Pseudoexfoliation syndrome is a condition associated with the production and accumulation of a pathological protein (pseudoexfoliation material). Originally, the syndrome was recognised on the basis of its intraocular symptoms and had been considered to be an isolated eye disease for a long time. However, some 20 years ago it became clear that in pseudoexfoliation syndrome pseudoexfoliation material is present all over in the body. In the past decade, vascular dysfunction associated with this syndrome has been also recognised. Recent studies have shown that pseudoexfoliation syndrome is caused by genetic alterations affecting a lysil oxidaselike (LOXL) protein, LOXL1. LOXL1 has an important role in the synthesis of extracellular material. To our current knowledge, pseudoexfoliation syndrome is a systemic elastosis associated with oxidative stress. Its complications are in part ocular (development of nuclear cataract, zonular damage and development of pseudoexfoliative glaucoma) and in part systemic (dysfunction of capillaries, muscular and elastic arteries, impairment of baroreflex function, increase of arterial rigidity, development of aorta aneurism, recurrent venous occlusions and neurosensory hearing loss). Despite the recognition of the above complications, currently it is not possible to set guidelines of a potential cardiovascular screening for patients with pseudoexfoliation syndrome, since the frequency and significance of systemic complications vary across different populations.]

COMMENTS

0 comments

Further articles in this publication

Lege Artis Medicinae

[Dabigatran: a new oral anticoagulant agent for the prevention of stroke and systemic embolism in nonvalvular atrial fibrillation]

KANCZ Sándor

[In this article, we summarise the available information on dabigatran, focusing on clinical practice, in particular on the prevention of stroke and systemic embolism, the critical aspects of anticoagulant treatment with dabigatran, potential drug-drug interactions and adverse reactions in nonvalvular atrial fibrillation. The most important molecular characteristics of dabigatran are also described. We highlight the implications of safety issues that have emerged during everyday clinical practice.]

Lege Artis Medicinae

[The Genious of Pilinszky ]

CZEIZEL Endre

Lege Artis Medicinae

[Stress load and health risk behaviour among medical, dental and pharmacy school students]

SIMA Ágnes, KOVÁCS Eszter, CSEH Károly, BALÁZS Péter

[INTRODUCTION - This study aims to analyse interrelations of stress load, mental state and work related symptoms with health risk behaviour of medical, dental and pharmacy school students. SAMPLE AND METHODS - 473 fourthyear students participated, 73.4% of medical, 10.1% of dental and 16.5% of pharmacy school. Measuring stress, we used the validated version of Anderson's questionnaire for mental, physical and work related divisions. Those with high level of stress on the score system entered the risk groups in the relevant divisions. Among health risks, tobacco smoking, alcohol consume, illegal drugs and psychoactive pharmaceuticals were measured. RESULTS - 15.2% of students perceived mental and 7.8% physical complaints. Work related symptoms were in 26.0% indicated. The overall prevalence of health risks were found to be 12.1% for smoking, 36.2% for drinking, 30.9% for drug use and 9.1% for taking pharmaceuticals. There was a significant (p<0.001) association between taking pharmaceuticals and all the three risk divisions. CONCLUSIONS - The prevalence of smoking is low in all student groups, but three out of ten students are regularly consuming alcohol and some kind of illegal drugs, yet there is no significant association between these health risks and the stress phenomena. Using pharmaceuticals is relatively less frequent, but it must be concerned that these drugs are taken primarily to manage stress related problems.]

Lege Artis Medicinae

[A Philosophy Practice in Healthcare ]

NEMES László

Lege Artis Medicinae

[Renewing clinical practice - attitude and chores]

HALÁSZ Péter

All articles in the issue

Related contents

Hypertension and nephrology

[Incorporation of ortho- and meta-tyrosine into cellular proteins leads to erythropoietin-resistance]

MIKOLÁS Esztella Zsóka, KUN Szilárd, LACZY Boglárka, MOLNÁR Gergő Attila, SÉLLEY Eszter, KŐSZEGI Tamás, WITTMANN István

[Introduction: Erythropoietin (EPO) is a glycoprotein hormone, which is responsible for the proliferation and differentiation of erythroid cell lines. Since it is widely used as the treatment of renal anaemia, EPO-resistance is a common concern. Aims: We aimed to perform in vitro experiments to investigate a possible mechanism of EPO-hyporesponsiveness. Methods: We used a factor dependent erythroblast cell line (TF-1). Two independent observers calculated cell counts simultaneously on day 1; 2 and 3 in Bürker cell counting chambers. Colorimetric method was used to measure protein concentrations. Measurement of protein-bound para-, ortho- and meta-tyrosine was performed with reverse phase high performance liquid chromatography with fluorescence detection. We determined ERK and STAT5 activation using Western blot method. Results: In case of ortho- and meta-tyrosine pretreated cells time-dependent, EPOinduced proliferative activity was decreased compared to the 1.7 fold elevation of cell counts seen in para-tyrosine cultured cells. Protein concentration of ortho- and metatyrosine treated samples was significantly lower than control cells on the third day. Addition of para-tyrosine reclaimed EPO-sensitivity. Erythroblasts treated with orthoor meta-tyrosine contained lower concentrations of protein-bound para-tyrosine with higher ortho- and meta-tyrosine content. EPO dependent activation of ERK and STAT5 could be inhibited by ortho- or meta-tyrosine treatment. Conclusions: Elevated level of protein-bound ortho- and meta-tyrosine in erythroblasts can result in the pathological modification of intracellular signaling, leading to EPOhyporesponsiveness.]

Clinical Neuroscience

[The role of β-amyloid and mitochondrial dysfunction in the pathogenesis of Alzheimer’s disease]

SZARKA András

[Alzheimer’s disease is the most common form of dementia in mid- and late life. The 7-10% of the population over 65 and the 50-60% of the population over 85 are affected by this disease. On the contrary of its prevalence the pathogenesis of the disease is not well defined and there is no effective neuroprotective therapeutic agent. Three predominant neuropathological features of the Alzheimer’s disease brain are intracellular neurofibrillary tangles consisting mainly of the hyperphosphorylated protein t; the extracellular amyloid deposits (neuritic plaques) consisting of amyloid b peptide; and the extensive neuronal cell loss in the hippocampus and in portions of the cerebral cortex. The possible reason of the extensive neuronal cell loss can be the mitochondrial dysfunction observed in Alzheimer’s disease. Beyond the unclarified pathogenesis the causality of these characteristic neuropathologic phenomena are still unknown. In this study we would like to deal with two actual hypotheses, with the amyloid cascade and with the mitochondrial cascade hypotheses. We try to give an overview of these two hypotheses and to depict their interrelationship.]

Lege Artis Medicinae

[Basics of the medical use of ayahuasca: physiology of dimethyltryptamine]

FRECSKA Ede, KOVÁCS Attila, SZABÓ Attila, FERENCZ Csaba, MÓRÉ Csaba

[Ayahuasca is a brew made of two admixture plants containing dimethyltryptamine (DMT) and b-carbolines (harmine and tetrahydroharmine). The indigenous groups of the Amazonas basin have been using it for centuries as an ethnomedical substance in healing and spiritual-religious rituals. During the last two decades the brew has raised increased scientific and public interest worldwide about its healing effects. Present paper addresses the therapeutic potentials of ayahuasca use and outlines the cellular mechanisms behind - in focus of the s-1 receptor mediated action of DMT. The scientific investigation of ayahuasca is complicated by methodical problems, legal issues, and sociocultural preconceptions.]

Lege Artis Medicinae

[Relationship between adipokinome and lipid parameters in Hungarian obese patients]

LŐRINCZ Hajnalka

[Since the prevalence of obesity has been dramatically increasing worldwide, a better understanding of obesity-related comorbidities leading to carbohydrate and lipid metabolism disorders has become essential. As an active endocrine organ, white adipose tissue secretes adipokines with diverse biological functions. We have found strong correlations between serum chemerin level and atherogenic lipoprotein sub-fractions in obese non-diabetic patients. To better characterize obese patients with and without manifest insulin resistance, we plan to determine serum levels of novel adipokines (omentin-1, vaspin, visfatin, lipocalin-2 and plasminogen activator inhibitor-1) and various oxidative stress markers including paraoxonase-1 activity, tumor necrosis factor-alfa and interleukin-6 levels, as well as low- and high-density lipoprotein subfractions in them and compare their data with lean individuals. We plan to determine correlations between the levels of novel adipokines and oxidative stress markers and lipoprotein subfractions. Furthermore, based upon our previous observations, we plan to study the potential alterations in the adipokine profile and the ratios of lipoprotein subfractions during a 5-year follow-up in obese patients. Our expected results may help to characterize the involvement of the adipokine profile in the regulation of lipoprotein metabolism. Early screening and treatment of lipid abnormalities may help to reduce the risk of cardiovascular events in obesity. ]

Hypertension and nephrology

[Plasma ortho-tyrosine/para-tyrosine ratio predicts hyporesponsiveness to erythropoiesis-stimulating agents in dialyzed patients]

KUN Szilárd, MIKOLÁS Esztella, MOLNÁR Gergő Attila, SÉLLEY Eszter, LACZY Boglárka, CSIKY Botond, KOVÁCS Tibor, WITTMANN István

[Objectives: Patients suffering from end-stage renal failure (ESRF) are mostly treated with erythropoiesis-stimulating agents (ESAs). They often show hyporesponsiveness to ESA, which condition is associated with elevated production of free radicals. Phenylalnine (Phe) is converted into para- and ortho-tyrosine (p- and o- Tyr) by hydroxyl free radical. o-Tyr is produced exclusively in this way. However, physiological isomer p-Tyr is formed in significantly higher amounts by phenylalaninehydroxylase, mainly in the kidney. It has been shown that p-Tyr production is decreased in ESRF. As a result, p-Tyr can be replaced by o-Tyr in proteins, e.g. in proteins playing part in signal transduction of erythropoietin. We aimed to study the association of different Tyr isoforms with ESA-responsiveness. Methods: Four groups of volunteers were involved in our cross-sectional study: healthy volunteers (CONTR; n=16), patients on hemodialysis without ESA-treatment (non-ESA-HD; n=8), hemodialyzed patients with ESA-treatment (ESA-HD; n=40) and patients on continuous peritoneal dialysis (CAPD; n=21). Plasma p-, o-Tyr and Phe levels were detected using a high performance liquid chromatography (HPLC)-method, with fluorescence detection. ESA-demand was expressed as ESA-dose, ESAdose/ body weight and erythropoietin resistance index1 (ERI1, weekly ESA-dose/body weight/hemoglobin). Multivariate regression models were used to examine predictors of ESA-demand. In these models, most of the known predictors of ESA-hyporesponsiveness were included. Results: Lower p-Tyr levels were found in dialyzed patients compared with control subjects. In contrast, o-Tyr levels and o-Tyr/p-Tyr ratios were higher in dialyzed patients. Regarding dialyzed patients, o-Tyr level and o-Tyr/p-Tyr ratio were higher in ESA-HD than in non-ESA-HD and CAPD groups. Weekly ESA-dose/body weight and ERI1 correlated with o-Tyr/p-Tyr ratio (r=0.441, p=0.001; r=0.434, p=0.001, respectively). Finally, o-Tyr/p-Tyr ratio proved to be an independent predictor of ERI1 (β=0.330, p=0.016). Discussion: Our results suggest that elevation of o-Tyr/p-Tyr ratio could be responsible for ESA-hyporesponsiveness in dialyzed patients.]