Specialities

Immune Oncology

Lege Artis Medicinae

OCTOBER 01, 2000

[Molecular mechanisms of cardiac hypertrophy and heart failure]

MIKALA Gábor, PETŐ Mónika, VÁLYI Nagy István, CSÁSZÁR Albert

[In this review, the most important molecular mechanisms leading to cardiac muscle hypertrophy and consequentially to heart failure are detailed. In numerous instances, understanding molecular mechanisms offers the possibility for pharmacotherapeutic intervention. First, trimeric G-proteins and their attached intracellular signaling pathways are introduced, with special emphasis on the pathways elucidated by transgenic animal models. In this area, there are several clinically effective drugs to influence cardiac hypertrophy, including ACE inhibitors, angiotensin receptor antagonists, as well as a- and B-adrenergic receptor blockers. Mitogen activated protein kinases participate later in the hypertrophic cascade. There are ongoing investigations on the potential therapeutic use of lipid-soluble statins these are indirect inhibitors of Ras-farnesylation. Altered cellular Ca2+-homeostasis is fundamental with respect to cardiac muscle hypertrophy and heart failure. The third part of this article investigates the role of the calcium/calmodulin dependent protein phosphatase called calcineurin in these processes. Administration of cyclosporin A or tacrolimus (both are inhibitors of calcineurin) may not be recommended in most forms of cardiac hypertrophy, however, in certain settings they may prove to be valuable therapeutic agents. One of the most serious, not yet properly addressed problem of late stage heart failure is the development of ventricular arrhythmias caused by repolarization abnormalities. Certain mechanisms of this phenomenon are highlighted with a special note on Nat-Cat exchange inhibitors as one of future therapeutic agents of much promise. ]

Lege Artis Medicinae

OCTOBER 01, 2000

[Molecular mechanisms of the link between obesity, insulin resistance and type 2 diabetes]

CSEH Károly, SALAMON Ferenc, SZEKERES Orsolya, SPEER Gábor, TÓTH János , WINKLER Gábor

[Causal link between obesity and type 2 diabetes has already been generally accepted. Alterations in the regulation of central nervous control of food intake, in the adaptive termogenesis and in the endocrinological function of the adipose tissue have foremost importance. Concerning the control of food intake leptin, Agouti-related protein as well as the pro-opiomelanocortin system and its receptors may have pivotal role in developing insulin resistance. In altering the control of adaptive termogenesis leading to obesity and concomittant insulin resistance, the mutations of the Bz-adrenergic receptors and the uncoupling proteins are important factors. Key mediators found in adipose tissue regulating insulin sensitivity are the non-esterified fatty acids, components of the tumor necrosis factor system and leptin, with the peroxysome proliferator activating receptor being the main genetic regulator of these adiposity signal molecules, ]

Lege Artis Medicinae

OCTOBER 01, 2000

[Metabolic syndrome - metabolic risk factors]

AUDIKOVSZKY Mária, PADOS Gyula

[Since abdominal type obesity, diabetes mellitus and the metabolic syndrome were classified as primary coronary risk factors beside hypercholesterolaemia and smoking, five out of six of the most significant risk factors are regarded of metabolic origin. Simultaneous occurrence of these factors are far more frequent in the population. The composition and background of this syndrome were subject of numerous analyses and classification from syndrome-X to metabolic syndrome. Reaven finds insulin resistance and compensatory hyperinsulinism as the primary cause, while Matsuzava et al regards visceral type obesity (visceral fat syndrome), and Björntrop views the increase in sympathetic tone (civilization syndrome) as fundamental. In the diagnostics and therapy of the metabolic syndrome we should consider all factors mentioned above. We have to establish the presence of three or more classic risk factors for a firm diagnosis. In the therapy, decreasing the body weight with diet and exercise is crucial, with adjuvant drug therapy of antidiabetics, insulinsensitizers, lipid lowering agents and antihypertensives, as needed. ]

Journal of Nursing Theory and Practice

AUGUST 30, 2020

[Beliefs and Misconceptions about Vaccination]

INHOFF Edina, GYERGYÁK Kinga, ILLYÉS-KOVÁCS Anita, LUKÁCS Erzsébet , TURCSÁN Judit

[Vaccination is one of the most effective public health interventions against infectious diseases, especially against vaccine-preventable paediatric diseases. However, there are parents either delaying or refusing recommended childhood vaccination due to the fear of a ‘link’ between vaccinations and autism or other diseases. Religious objection is often used as an excuse to avoid the vaccination. Opposition to vaccination dates back to the Victorian age. Since the 18th century, fear and controversy accompanied the introduction of every new vaccine. This has been compounded, in recent years, by a decreased trust in the vaccine manufacturing or distributing institutions. Although healthcare professionals are cited as the most influential source by parents and adult population on vaccine decision-making, mistrust of vaccinations is already occurs among health workers. It is important for health professionals to be well informed, to able to persuade parents and the targeted population to vaccine.]

Lege Artis Medicinae

JUNE 01, 2000

[Postnatal development of the human hippocampal formation]

SERESS László

[Jean Piaget's theory suggests that cognitive development proceeds in discrete steps. The first is the sensorimotor period that happens in the first two years of life. In recent years it became clear, that it is necessary to have an intact and mature hippocampus for adequate memory formation, both in experimental animals and humans. In the present study, the morphological development of the human hip pocampus was correlated with the developmental changes of intellectual development. Our results suggest that neuronal cell formation of the human hippocampus terminates several weeks before birth. In the dentate gyrus, a small number (less than 1%) of granule cells are still formed around birth. Immature granule cells migrate through the hilar region to their final position in the granule cell layer during the first six postnatal months. Light microscope studies of individual neurons indicate that connections between granule cells and their target neurons are not yet formed at birth. Such connections develop during the third postnatal year. If the development of the synaptic connections is damaged in experimental animals, the hippocampal function will be permanently impaired. Newborns may have basic synaptic circuits for memory formation, but the postnatal morphological changes suggest the significant modification of the hippocampal circuits happening continuously from the newborn age until late childhood. These changes may cause the phenomenon of the "infantile amnesia". ]

Lege Artis Medicinae

JUNE 01, 2000

[Pathophysiology of myocardial ischemia and reperfusion]

PAPP Zoltán, ÉDES István

[Complete and long lasting loss of coronary circulation results in myocardial cell death (ischemic necrosis). Short lasting ischemia (few minutes) is well tolerated and it may bring certain protection against recurrent ischemia (ischemic preconditioning). Contractile force promptly diminishes following the onset of ischemia and the changes in the intracellular ATP or Ca2+ concentration do not explain this phenomenon. With the progression of ischemia, myocardial relaxation ceases and hypertonic muscle activation appears (ischemic contracture). During myocardial reperfusion following short-term ischemia, arrhythmias often develop and pump function is regularly depressed transiently (myocardial stunning). Permanent reduction in coronary blood supply results in sustained ventricular dysfunction (hibernation). It has been established, that pathologic processes leading to ischemic injury are distinct from those of reperfusion injury. Cellular events are complicated (Ca2+-overload, free radical injuries, activation of proteolytic processes, energy loss, membrane damage, hypercontracture, etc.), and complete understanding of the background of ischemic/reperfusion disorders is still awaited. ]