Lege Artis Medicinae

[CONTROVERSIAL EFFECTS OF NITRIC OXIDE: INTEGRITY AND TOXICITY]

KISS Róbert Gábor, BÉRES Bernát János

JULY 14, 2007

Lege Artis Medicinae - 2007;17(06-07)

[Nitric oxide is a key molecule of the human body. Since its discovery, a library of books and papers have been published on its physiological and pathophysiological role. It is involved in almost all pathological processes. In healthy individuals nitric oxide plays a crucial role in the vascular regulation by protecting against atherosclerosis, myocardial infarction and stroke. In the central nervous system, nitric oxide in its function as a neurotransmitter is responsible for synaptic plasticity, long-term potentiation, memory and a number of neuroendocrine control mechanisms. Furthermore, during inflammation and host defense, macrophages and neutrophils produce nitric oxide that has antibacterial, antiviral, and tumour cell killing activity. In pathologic conditions, however, nitric oxide reacts with superoxide anion to form peroxynitrite that damages the enzymes of the mitochondrial respiratory chain, superoxide-dismutase, reduced glutathion and activates or inactivates signalling molecules. During ischaemia- reperfusion, nitric oxide and peroxynitrite contribute to nitrative/nitrosative stress, DNAfragmentation and consequent polyADP-ribosepolymerase- 1 enzyme activation both in coronary thrombosis and ischaemic stroke.]

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Lege Artis Medicinae

[THE USE OF DIURETICS AND ALDOSTERONE RECEPTOR ANTAGONISTS IN CHRONIC HEART FAILURE]

NYOLCZAS Noémi

[Diuretics are an integral part of the management of chronic heart failure. Although there are no large, randomized, placebo-controlled, multicentric studies available to show that loop- and thiazid diuretics improve survival, the efficacy of these drugs in relieving heart failure symptoms and fluid retention is indisputable. The third class of diuretics used in heart failure is aldosterone antagonists, whose beneficial effects on mortality and morbidity were demonstrated in the RALES and EPHESUS trials. In this paper, the effects and side effects of the various diuretics, as well as the indications and recommendations on their use are reviewed. New options in diuretic treatment, including adenosine receptor blockers, vasopressin antagonists, atrial natriuretic peptide analogues and ultrafiltration are also presented.]

Lege Artis Medicinae

[Clinical consensus conference on COPD]

TAMÁSI Lilla

Lege Artis Medicinae

[THE SAFETY OF TREATMENT WITH PEGYLATED INTERFERON-ALPHA-2A AND RIBAVIRIN IN PATIENTS WITH CHRONIC HEPATITIS C INFECTION, BASED ON HUNGARIAN EXPERIENCE]

WERLING Klára, DALMI Lajos, GERVAIN Judit, HORVÁTH Gábor, NAGY István, NEMESÁNSZKY Elemér, RIBICZEY Pál, TELEGDY László, VARGA Márta, TORNAI István, TULASSAY Zsolt

[INTRODUCTION - Adverse effects of treatment for chronic C virus hepatitis present an important problem both for the patient and the clinician. The reduction of drug doses or the suspension of therapy lessen the likelihood of recovery. PATIENTS, METHODS - Between 2001 and 2004, 66 patients with chronic hepatitis C received 180 μg pegylated interferon-alpha-2a per week and 800-1200 mg ribavirin per day, 6 of whom for 24 weeks and 60 patients for 48 weeks. During treatment, patients were closely followed in order to recognize any adverse effects early. RESULTS - Of the patients treated for 48 weeks, 48.3% developed adverse effects, with changes in the differential in 41.7%, and anaemia, low platelet count, neutropenia in similar rates. Further side effects included cardiac complications, skin symptoms, persisting high fever, autoimmune thyroiditis and liver failure, altogether in 9 cases. Dose reduction or temporary suspension of pegylated interferon-alpha-2a was necessary in 21 cases (31.7%), while complete cessation of this treatment was decided in 7 cases, most of them because of blood count changes. The 1000 to 1200 mg per day ribavirin had to be reduced in 30.8% of patients, while treatment was stopped in 3 cases. Long-term virological remission occurred in 48% of patients who received treatment for 48 weeks, whereas no such result was observed among any of those treated for 24 weeks. CONCLUSION - Adverse effects of variable severity developed in nearly half of the patients with chronic hepatitis C infection who received antiviral treatment for 48 weeks, but treatment had to be stopped in only a small proportion of this group. Early treatment of adverse effects can prevent the need to cease therapy and may improve its efficiency.]

Lege Artis Medicinae

[Lorenzo da Ponte The Librettist of Mozart]

dr. KÖVES Péter

Lege Artis Medicinae

[ACE-INHIBITORS IN THE SECONDARY PREVENTION OF CORONARY ARTERY DISEASE]

SÁRSZEGI Zsolt

[The beneficial effects of angiotensin-converting enzyme inhibitors on biochemical and vascular markers have been proven by many experimental studies. Reduction of the angiotensin-II level has a positive effect on oxidative stress, lipid peroxidation, apoptosis, inflammatory and prothrombotic processes. Two large multicentric trials, EUROPA and HOPE, showed that perindopril and ramipril significantly reduce mortality and the risk of both fatal and non-fatal cardiovascular events in patients with atherosclerosis, thereby making them the base drugs of secondary prevention of coronary artery disease.]

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Hypertension and nephrology

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Lege Artis Medicinae

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Lege Artis Medicinae

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Hypertension and nephrology

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