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Prednáška „Dozimetria - Meranie ionizujúceho žiarenia“ je zameraná na vysvetenie pojmu dozimetria a základných veličín, ktoré charakterizujú žiarenie z hľadiska jeho biologických účinkov a umožňujú ho merať a kvantifikovať. Ide o pojmy ako dávka, absorbovaná dávka, príkon absorbovanej dávky, integrálna dávka, dávkový ekvivalent, efektívna dávka, kerma, kermový príkon, expozícia, expozičný príkon a s nimi súvisiace vzťahy a fyzikálne jednotky.

LF UK v Bratislave | discipline: Biophysics | keywords: dávka, absorbovaná dávka, príkon absorbovanej dávky, integrálna dávka, dávkový ekvivalent, efektívna dávka, kerma, kermový príkon, expozícia, eExpozičný príkon | published on: 16. 4. 2012

The lecture „Radioactivity“ is aimed to explain basic terms as radioactive isotopes, natural and artificial radioactivity, law of radioactive decay, half-life of decay (physical, biological, effective), mean life-time, activity and connected formulas and physical units.

LF UK v Bratislave | discipline: Biophysics | keywords: radioactive isotopes, natural and artificial radioactivity, law of radioactive decay, half-life of decay, mean life-time, activity | published on: 16. 4. 2012

Prednáška „Rádioaktivita“ je zameraná na vysvetenie základných pojmov ako rádioaktívne izotopy, prirodzená a umelá rádioaktivita, zákon rádioaktívnej premeny, doba polpremeny (fyzikálna, biologická, efektívna), stredná doba života, aktivita a s nimi súvisiace vzťahy a fyzikálne jednotky.

LF UK v Bratislave | discipline: Biophysics | keywords: rádioaktívne izotopy, prirodzená a umelá rádioaktivita, zákon rádioaktívnej premeny, doba polpremeny, stredná doba života, aktivita | published on: 16. 4. 2012

Type I hypersensitivity belongs to the most common disorder mediated by immune reactions; it affects app. more than 30% of all individuals in Caucasoid population. Type I hypersensitivity is commonly called allergy. It is characterised by rapid onset (hence the term immediate hypersensitivity), within minutes of antigen challenge, and results in conspicuous clinical symptoms.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Allergy, anaphylaxis, atopy, IgE antibodies, histamine | published on: 4. 4. 2012

The lecture „Basic elements of electric circuits“ is aimed to explain basic terms, quantities and units  It contains basic electrical values like electric current, electric resistance next measurement of electrical quantities and elements of electric circuit.

LF UK v Bratislave | discipline: Biophysics | keywords: Electric circuit, electric current, electric resistance | published on: 28. 3. 2012

Prednáška „Základné prvky elektrických obvodov“ je zameraná na vysvetlenie základných pojmov, veličín a jednotiek. Obsahuje základné elektrické veličiny ako elektrický prúd, elektrický odpor, ďalej meranie elektrických veličín a prvky elektrického obvodu.

LF UK v Bratislave | discipline: Biophysics | keywords: Elektrický obvod, elektrický prúd, elektrický odpor | published on: 28. 3. 2012

The 100th anniversary of the Student´s statistical t-distribution is commemorated.                                                                                                                                                                              

LF UK v Bratislave | discipline: Biophysics | keywords: Statistics, StudentXXCentury, Student100yNEL05 | published on: 28. 3. 2012

The monthly registered Wolf numbers (i.e the numbers of sunspots), solar flares index and Ap index of the geomagnetic activity values display negative regression dependence („negatively correlate“) upon the monthly observed numbers of new cases of cerebral infarction.This phenomenon is present with delays from -6 months (infarction before the cosmogeophysical measurement) up to + 17 months (infarction after the cosmogeophysical measurement),with the most pronounced relationship for delay of +5 months.

LF UK v Bratislave | discipline: Neurology | keywords: NeuroEndoc rino, NeuroPsychiatry, Stroke, CerInfSolGeoma IMAJ07 | published on: 28. 3. 2012

Russian scientist Tchijevskij investigated almost 100 years ago (suggested for Nobel prize) relationships between solar activity, cycling with the period around 11 years, and the status of mankind. He found „social excitation“, as revolutions and wars, at the time of solar maxima and peaceful activities like flourishing of arts at minima.The present paper explores whether such a parallelism applies also to the 500 years´ (semimillenial) cycling of solar activity. The present author obtained, using the cosinor analysis, significant positive anwer. It is hypothesized that one of the responsible factors could be solar impact on geomagnetic field.

LF UK v Bratislave | discipline: Psychiatry, Psychology, Sexology | keywords: Socioeconomy, Sociology, History, RevolCultSolarNEL2007 | published on: 28. 3. 2012

Distinct increase in the incidence of this disease, observed in Central and Eastern Europe recently, was registered also in Slovak children. Nevertheless, an original finding is the significant presence of 10-11-years cycling, corresponding probably with that in the solar activity, and of 7-years cycling, known for geomagnetic activity These periodicities are superposed on an increasing linear trend, affirmed in some Western „main stream“ journals (e.g.Diabetologia) as the only pattern in this issue.

LF UK v Bratislave | discipline: Diabetology, Dietetics | keywords: Diabetes, DiabetesIncidence, DiaIncWNApNEL03 | published on: 28. 3. 2012

Ročné počty nových pacientov v Českej republike (1965-2003), Slovenskej republike (1980-2003) a na Sibíri (1955-1994), tu aj s klimatickými teplotami, vykazujú zhodne vzostup, okrem ochorení na Sibiri štatisticky významný.

LF UK v Bratislave | discipline: Epidemiology, Preventive Medicine, Hygiene | keywords: Epidemiology, TickBorneEncephalitis, KliešEncOteplÚp06 a TickGlobOtepÚp06 | published on: 28. 3. 2012

Yearly numbers of new cases of this disease, collected over one half century,were processed by uncostomed biometrical tools – testing of randomness of the time sequence using Poisson and „contagious“ distributions, cosinor regression and crosscorrelation.The older experience of these authors – cycling of the daily numbers of cases during synodic lunar cycle – has been extended to the years´ scales: cycling contemporal with the Moon nutation period was found as significant. It is another evidence for a putative effect of gravity on bacterial virulence of Salmonella. In the mean time, experiments in NASA laboratories,USA found a dangerous increase of Salmonella virulence in microgravity conditions. Practical consequencies for the medical securing of space flight crews are indicated.

LF UK v Bratislave | discipline: Epidemiology, Preventive Medicine, Hygiene | keywords: Epidemiology, Salmonellosis, SalmIsrael, Slovak, Czech, SalmonIncidSlov1957-08 | published on: 28. 3. 2012

Annual incidence rates of 3157 cases of leptospiroses recorded within 1949 and 2004, caused by the main serovars ificant or borderly significant periodicities, resembling those known from solar and geomagnetic activity, were identified. By comparing them with the time course of Wolf numbers, an almost exact reciprocity of maxima and minima of Wolf numbers and leptospiroses was disclosed. It is hypothetized that the epizoonotic character of these diseases supports the putative dependence of its manifestation upon the nature including the sun. Surprisingly, no similar results were found, so far, in the world scientific registers.

LF UK v Bratislave | discipline: Epidemiology, Preventive Medicine, Hygiene | keywords: Epidemiology, Leptospirosis, LeptSRÚp07Bul185 | published on: 28. 3. 2012

Incidence of toxocarosis in Slovakia 1977-1990 showed an exponential increase with an accessory cycling, having 7-8 years period length.                                                 

LF UK v Bratislave | discipline: Epidemiology, Preventive Medicine, Hygiene | keywords: Epidemiology, Toxocarosis, ToxocaraMik1992 | published on: 28. 3. 2012

The 24-hour profile of hourly registered extrasystoles mean counts per one subjest in apparently healthy elderly males was studied with the aid of Halberg cosinor regression.

LF UK v Bratislave | discipline: Cardiology, Angiology | keywords: Cardiology, ExtrasystCircaUltraDian, Health, HealLowAPhysiolHun08 | published on: 28. 3. 2012

Rotor syndrome is a rare familial conjugated hyperbilirubinaemia with notmal liver histology and unknown cause. The hypothesis was tested that it can be an allele variant of Dubin-Johnson syndrome, caused by mutation in ABCC2 gene. The ABCC2 gene and protein were investigated in two patients with this syndrome. No sequence variations were found in 32 exons, adjacent intronic regions and the promoter region of ABCC2. Accordingly, Rotor syndrome is not an allelic variant of ABCC2 deficiency.

LF UK v Bratislave | discipline: Biology | keywords: HepGastroEnt, BenignJaundice, RotorBiPumpLiveInt2007 | published on: 28. 3. 2012

Protein antigens are no able to induce an immune response without being previously processed by antigen presenting cells (APCs). Following their processing that comprises their splitting to smaller fragments – peptides, APs subsequently present them to T cells; moreover, they activate them and polarise to a specific biological functions. Depending of antigen origin, there are two presentation pathways, exogenous and endogenous. Antigens originated from outside of APC, e.g. bacterial toxins, enzymes, etc., are presented by exogenous pathway and presented molecules are class II HLA molecules. T cell, that recognise presented peptides belong to helper subset of T cells. Antigens originated in the cytosol, such as antigens that appear in the cytoplasm of virus infected cells, are presented by endogenous pathway and presented molecules belong to class I HL-A molecules. T cells, that recognise presented peptides, represent cytotoxic T cells.  

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Antigen presenting cells, HLA molecules, T cells and their subsets | published on: 28. 3. 2012

Histokompatibilné molekuly sú geneticky determinované proteíny, ktorá sa nachádzajú v membránach všetkých jadrových buniek. Vytvárajú ucelený systém, ktorý sa označuje ako hlavný histokompatibilný komplex (MHC – Major Histocompatibility Complex). Každý živočíšny druh má svoj MHC; u ľudí sa označuje skratkou HLA. Táto vznikla z prvých písmen označenia “Human leucocyte antigens” pretože prvé jeho molekuly boli objavené na leukocytoch.  

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: histokompatibilné molekuly, HLA-systém, polymorfnosť, transplantácie, asociácia s chorobami, paternitné spory | published on: 16. 3. 2012

Histocompatibility molecules are genetically determined proteins present in membranes of all nucleated cells. They form a unique system for which the term “Major Histocompatibility Complex (MHC)” was coined. Each vertebrate species is characterised by its own MHC; that of humans has an abbreviation HLA. This acronym is derived from the words: “human leucocyte antigens” as its fist molecules were discovered in membranes of leucocytes.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: histocompatibility molecules, HLA system, chromosome 6, antigen presentation, transplantations, associations with diseases | published on: 16. 3. 2012

Cytokines are soluble peptides that induce activation, proliferation and differentiation of cells of the immune system. Moreover, cytokines influence functions of cells of other tissues and organs, esp. of nervous and endocrine systems. They act in very low concentrations (10-10 M) what makes them to be like hormones. However, hormones tend to be produced constitutively and are produced by endocrine organs. Cytokines, on the contrary, are secreted after activation of particular cells and secretion is short-lived, generally ranging from a few hours to a few days and there are no specialised organs for their synthesis. Cytokines influence target cell in 4 different ways, synergistic, antagonistic, pleiotropic, and redundant way, respectively. They ca act in a autocrine, paracrine and endocrine manner. There are many cytokines that can be divided into those regulating innate and adaptive immunity, to the group of cytokines endowed by chemotactic properties and those supporting growth of hematopoietic and immune system cells.  

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Cytokines, interleukins, molecular patterns of germs | published on: 16. 3. 2012

Phagocytosis is a process of bacteria engulfment and their killing. The phagocytic cells of mammals belong to two complementary systems, the myeloid and mononuclear-phagocytic systems. The myeloid system consists of cells that phagocyte rapidly, however they are not able of sustained effort. Tthey are represented by neutrophils and eosinophils. In contrast, cells of the mononuclear-phagocytic system act more slowly but are capable of repeated phagocytosis. Mmonocytes and macrophages are principal cell responsible for. Process of phagocytosis can be divided into several steps: chemotactic movement of phagocytes towards invading bacteria, opsonisation and recognition of bacteria by specific receptors, their engulfment and phagolysosome formation, bacteria killing and resolution. Bacteria can be killed by oxygen or nitrogen dependent mechanisms and by various antibacterial substances.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Chemotaxis, cytokines, opsonins, phagocytosis, inflammation, prostaglandins | published on: 8. 3. 2012

Protilátky nás pred mikroorganizmami chránia principiálne dvoma spôsobmi: obaľovaním ich povrchu (opsonizácia), čo uľahčuje ich pohltenie a usmrtenie fagocytmi, alebo ich lýzou. V tomto poslednom prípade však potrebujú pomoc zo strany komplementového systému. Tento tvorí viac ako 35 proteínov, ktoré produkuje najmä pečeň a makrofágy, čo umožňuje jeho aktiváciu kdekoľvek v organizme kde prebieha zápal. Zložky komplementu sú súčasťou proteínov plazmy a reprezentujú 10% z globulínovej frakcie.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Protilátky, komplement, deficiencie, receptory | published on: 28. 2. 2012

The lecture „Passive electrical properties of tissues“ is aimed to explain basic terms, quantities and units necessary to understand electrical properties of biological tissues. It contains physiological values of individual quantities for some tissues and organs, electrical model of these properties, describes effect of electric current on tissues and its use in diagnostics and therapy. The lecture also includes safe values of electric current and rules for event of injury by electric current.

LF UK v Bratislave | discipline: Biophysics | keywords: basic electric quantities, passive electric properties of tissues, electric model of tissue, effect of electric current on tissue | published on: 27. 2. 2012

Prednáška „Pasívne elektrické vlastnosti tkanív“ je zameraná na vysvetlenie základných pojmov, veličín a jednotiek potrebných k porozumeniu elektrických vlastností biologických tkanív. Obsahuje fyziologické hodnoty jednotlivých veličín pre niektoré tkanivá a orgány, elektrický model týchto vlastností, opisuje účinok elektrického prúdu na tkanivá a jeho využitie v diagnostike a terapii. Súčasťou prednášky sú aj bezpečné hodnoty elektrického prúdu a postup pri úraze elektrickým prúdom.

LF UK v Bratislave | discipline: Biophysics | keywords: základné elektrické veličiny, pasívne elektrické vlastnosti tkanív, elektrický model tkaniva, účinok elektrické ho prúdu na tkanivo | published on: 27. 2. 2012

Verejnosť vníma imunológiu ako vednú disciplínu, ktorá sa zaoberá štúdiom obranných mechanizmov proti mikroorganizmom, infekčným chorobám. Dnes však Imunológiu vnímame širšie, ako vednú disciplínu, ktorá študuje bunkové a molekulové procesy, ktoré sa odohrávajú v organizme človeka, či zvierat alebo rastlín po vniknutí akejkoľvek cudzej látky do tela. K rozvoju imunológie prispeli početné významné osobnosti, zmieňme sa len o takých velikánoch ako boli Louis Pasteur, Ilja Mečnikov, Jean Dausset a mnohí, mnohí ďalší; svedčia o tom Nobelove ceny, ktoré sa skoro každé 3 – 4 roky dostanú vedeckí pracovníci na poli imunológie. Táto skutočnosť je odrazom prudkého rozmachu tohto fascinujúceho vedného odboru a jeho veľkému významu pre biológiu a medicínu.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Míľniky vývoja imunológie, Imunitný systém, Antigén, krvné skupiny | published on: 27. 2. 2012

Protilátky sú molekuly glykoproteínovej povahy, ktoré dokážu špecificky viazať antigén či už solubilný alebo ako súčasť membrány bunky. Nachádzajú sa v plazme alebo tesných tekutinách (lymfa, sliny, slzy, ...). Pretože protilátky patria prevažne gama-globulínovej frakcii plazmy, označovali sa pôvodne ako gamaglobulíny; v súčasnosti ich označujeme ako imunoglobulíny (Ig). Poznáme 5 tried imunoglobulínov: IgG, IgM, IgA, IgE, a IgE. Každá z nich má svoju charakteristickú biochemickú štruktúru a biologickú funkciu. Principiálne úloha protilátok je väzba antigénov; okrem toho však majú aj početné iné funkcie, ako je väzba komplementu, prechod placentou, opsonizácia baktérií, väzba na receptory viacerých buniek imunitného systému a pod.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Protilátky, imunoglobulíny, gamaglobulíny, B-lymfocyty, plazmatické bunky | published on: 27. 2. 2012

Common people perceive Immunology as a scientific branch that studies defence of an organism against germs, cancer cells, toxins etc. Nowadays, Immunology is defined a scientific branch that studies immunity, its cellular and molecular processes that proceed after a foreign substance, an antigen, enters our body. There are many notable personalities who contributed to its development. Let us mention only some of them – Louis Pasteur, Ilja Mecnikov, Jean Dausset and many, many others. They contributed to the fact that Immunology belongs to those scientific disciplines that develop the most intensively in recent years.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Milestones of Immunology, notable personalities, Structure and function of the immune system, Antigens, ABO and Rh blood groups | published on: 27. 2. 2012

Antibodies manage to protect us against germs principally by two ways: by enveloping their surfaces (opsonisation), what makes their engulfment and killing by phagocytes easier and more effective or by cell lysis. However, in this case, they need a help from the complement system.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Antibodies, complement, lysis of target cells, imune complexes, deficiencies of C | published on: 27. 2. 2012

Antibodies are molecules of glycoprotein nature that have ability to bind antigens either soluble or bound in membranes of cells in a specific way. They are present in plasma and in tissue fluids (lymph, saliva, tears etc.). As most of antibodies belong to the gamma globulins of plasma proteins, they were previously known under the term gammaglobulins; their contemporary nomenclature is immunoglobulins (Ig). There are five classes of immunoglobulins: IgG, IgM, IgA, IgE, and IgE, respectively. They have specific biochemical structure and function. The principal biological role is to bind antigens; except it, they can activate the complement, opsonise bacteria, bind to receptors of various cell of the immune system etc.

LF UK v Bratislave | discipline: Immunology, Allergology | keywords: Antibodies, immunoglobulins, B cells, plasma cells | published on: 27. 2. 2012

The presentation deals with active electric biosignals originating from the electric activity of the heart and with different possibilities of their registration and analysis. Suitable to all study branches.                                                                                                                                                  

LF UK v Bratislave | discipline: Biophysics | keywords: resting electrocardiography, vectorcardiography, high-resolution electrocardiography, body surface potential mapping, Holter monitoring | published on: 23. 2. 2012