Search Results

You are looking at 1 - 10 of 10 items for :

  • Author or Editor: M. Gabal x
  • Medical and Health Sciences x
  • Refine by Access: All Content x
Clear All Modify Search

Ervin Bauer is one of the first theoretical biologists distancing his ideas both from vitalism and mechanicism. He formulated the principle of permanent non-equilibrium of living systems (Bauer’s principle) in terms of thermodynamics in 1920. Bauer’s scientific path can be divided into three periods. In the early 1920s he proposed his principle as an axiom that cannot be derived from contemporary natural sciences. In the late 1920s he reformulated it in a way that it could be subjected to experimental testing. Summarizing his views in the 1930s in his book, Theoretical Biology, he tried to show that his axiom is indeed the fundamental principle of biology. This later view was anachronistic in spite of many striking insights of Bauer. The energetic formulation of Bauer’s principle is, however, a realistic characterization of living organisms and it can be derived from the theory of open systems — in fact it contributed to the formulation of that theory. Bauer’s principle can be incorporated into non-linear thermodynamics of irreversible processes.

Restricted access

In our previous review characteristics of the athlete’s heart were divided into three groups: morphologic (left ventricular (LV) hypertrophy, improved coronary circulation), functional (better diastolic function) and regulatory (lower heart rate (HR)) features. In the present review, the influences of the types of sports and the age on the athlete’s heart are discussed. Studies using echocardiographic, Doppler-echocardiographic, tissue Doppler imaging (TDI) and magnetic resonance imaging (MRI) results are mostly involved. The coronary circulation was investigated overwhelmingly in animal experiments. In the LV hypertrophy a major contributor is the increase of the LV wall thickness (WT) than that of the LV internal diameter (ID). A right ventricular (RV) hypertrophy can also be seen in athletes. Athletic features are induced mostly by endurance training. Approximately two years regular physical training is needed to develop characteristics of the athlete’s heart, hence, in the young children they are less marked. LV hypertrophy and lower HR are characteristic in young and adult athletes, but they are less marked in older ones. A richer coronary capillary network can develop mostly at a young age.

Restricted access
Acta Physiologica Hungarica
Authors: Gábor Pavlik, Zs. Major, B. Varga-Pintér, M. Jeserich, and Zs. Kneffel

Importance of the athlete’s heart has been arisen in the last decades.

  1. Consequences of the sedentary way of life are the most threatening through the impairments of the cardiovascular system. Endurance performance is mostly limited by the characteristics of the athlete’s heart. Sudden death of the athletes is always associated with cardiac disorders.
Main characteristics of the athlete’s heart can be divided into morphologic, functional and regulatory ones.
  1. The main morphologic characteristics are the physiologic left ventricular (LV) hypertrophy and a richer coronary capillary network. The functional adaptation contains a better systolic and diastolic function, modified metabolism and electric characteristics. The most easily detected modification is the better LV diastolic function. Adaptation of the cardiac regulation is manifested mostly by a lower heart rate (HR).
Summarizing: the athlete’s heart is an enlarged but otherwise normal heart characterized by a low heart rate, an increased pumping capacity, and a greater ability to deliver oxygen to skeletal muscle.

Restricted access

The purpose of this cross-sectional investigation was to estimate the age at which specific traits of the “athlete's heart”first appear and how they evolve from the beginning of regular physical training until young adulthood in healthy active males. Male athletes (n=389) and non-athletes (n=55) aged between 9 and 20 years were examined by two-dimensionally guided M-mode and Doppler echocardiography. Intragroup differences were examined by t-tests for independent samples between age groups of two years each. Morphologic variables were related to body size by using ratio indices in which the power terms of numerator and denominator were matched. Relative left ventricular muscle mass (LVMM) was significantly larger in the athletic males at age of 11–12, and this significant difference was maintained with advancing age. Most of this increase of LVMM could be attributed to the increase in wall thickness that became significantly manifest first in the 13- to 14-year-old athletic subjects but was demonstrable in all the other groups. A significantly larger left ventricular internal diameter was only found in the age-group of 15–16. Fractional shortening percentage (FS%) did not show any change, while resting heart rate was decreased in our athletic groups.

Restricted access
Acta Physiologica Hungarica
Authors: P. Horváth, M. Petrekanits, I. Györe, Zs Kneffel, B. Varga-Pintér, and Gábor Pavlik

In the authors’ earlier study the relative aerobic power of Hungarian top-level male water polo players was found to be smaller than that of other top-level athletes, while their echocardiographic parameters proved to be the most characteristic of the athlete’s heart. In the present investigation echocardiographic and spiroergometric data of female top-level water polo players were compared to those of other female elite athletes and of healthy, non-athletic subjects. Relative aerobic power in the water polo players was lower than in endurance athletes. Mean resting heart rates were the slowest in the water polo players and endurance athletes. Morphologic indicators of the heart (body size related left ventricular wall thickness and muscle mass) were the highest in the water polo players, endurance and power athletes. In respect of diastolic functions (diastolic early and late peak transmitral flow velocities) no difference was seen between the respective groups.These results indicate that, similarly to the males, top-level water polo training is associated with the dimensional parameters of the heart rather than with relative aerobic power. For checking the physical condition of female water polo players spiroergometric tests seem to be less appropriate than swim-tests with heart rate recovery studies such as the ones used in the males.

Restricted access
Acta Physiologica Hungarica
Authors: Gábor Skaliczki, M. Weszl, K. Schandl, T. Major, M. Kovács, J. Skaliczki, H. Redl, M. Szendrői, K. Szigeti, D. Máté, Cs Dobó-Nagy, and Zs Lacza

Purpose: The clinical demand for bone grafting materials necessitated the development of animal models. Critical size defect model has been criticized recently, mainly for its inaccuracy. Our objective was to develop a dependable animal model that would provide compromised bone healing, and would allow the investigation of bone substitutes. Methods: In the first group a critical size defect was created in the femur of adult male Wistar rats, and a non-critical defect in the remaining animals (Groups II, III and IV). The defect was left empty in group II, while in groups III and IV a spacer was interposed into the gap. Osteoblast activity was evaluated by NanoSPECT/CT imaging system. New bone formation and assessment of a union or non-union was observed by μCT and histology. Results: The interposition model proved to be highly reproducible and provided a bone defect with compromised bone healing. Significant bone regeneration processes were observed four weeks after removal of the spacer. Conclusion: Our results have shown that when early bone healing is inhibited by the physical interposition of a spacer, the regeneration process is compromised for a further 4 weeks and results in a bone defect during the time-course of the study.

Restricted access
Acta Microbiologica et Immunologica Hungarica
Authors: Tamás Gáll, Gábor Lehoczki, Gyöngyi Gyémánt, Tamás Emri, Zsuzsa M. Szigeti, György Balla, József Balla, and István Pócsi

Siderophores are produced by a number of microbes to capture iron with outstandingly high affinity, which property also generates biomedical and industrial interests. Desferrioxamine E (DFO-E) secreted by streptomycetes bacteria can be an ideal candidate for iron chelation therapy, which necessitates its cost-effective production for in vitro and animal studies. This study focused on the optimization of DFO-E production by Streptomyces parvulus CBS548.68. Different combinations of various carbon and nitrogen sources as well as the addition of 3-morpholinopropane-1-sulfonic acid (MOPS) markedly affected DFO-E yields, which were attributed, at least in part, to the higher biomass productions found in MOPS-supplemented cultures. In MOPS-supplemented glucose and sodium glutamate medium, DFO-E productions as high as 2,009 ± 90 mg/l of culture medium were reached. High-performance liquid chromatography analysis demonstrated that a simple two-step purification process yielded DFO-E preparations with purities of ∼97%. Matrix assisted laser desorption ionization-time of flight mass spectrometry analysis showed that purified DFO-E always contained traces of desferrioxamine D2.

Restricted access
Acta Veterinaria Hungarica
Authors: Sándor Hornok, Attila D. Sándor, Gábor Földvári, Angela M. Ionică, Cornelia Silaghi, Nóra Takács, Anna-margarita Schötta, and Michiel Wijnveld

Abstract

Recently, the occurrence of Ixodes (Pholeoixodes) kaiseri has been reported for the first time in several European countries, but data on the molecular analysis of this hard tick species are still lacking. Therefore, in this study DNA extracts of 28 I. kaiseri (collected from dogs and red foxes in Germany, Hungary and Romania) were screened with reverse line blot hybridisation (RLB), PCR and sequencing for the presence of 43 tick-borne pathogens or other members of their families from the categories of Anaplasmataceae, piroplasms, rickettsiae and borreliae. Rickettsia helvetica DNA was detected in one I. kaiseri female (from a red fox, Romania), for the first time in this tick species. Six ticks (from red foxes, Romania) contained the DNA of Babesia vulpes, also for the first time in the case of I. kaiseri. Molecular evidence of R. helvetica and B. vulpes in engorged I. kaiseri does not prove that this tick species is a vector of the above two pathogens, because they might have been taken up by the ticks from the blood of foxes. In addition, one I. kaiseri female (from a dog, Hungary) harboured Babesia sp. badger type-B, identified for the first time in Hungary and Central Europe (i.e. it has been reported previously from Western Europe and China). The latter finding can be explained by either the susceptibility of dogs to Babesia sp. badger type-B, or by transstadial survival of this piroplasm in I. kaiseri.

Restricted access

Kezdeti tapasztalataink az mpMR fúziós ultrahangvezérelt prosztatabiopsziával

Our initial experiences with mpMRI-ultrasound fusion-guided prostate biopsy

Orvosi Hetilap
Authors: András Béla Hüttl, Dávid Ádám Korda, M. Zsuzsanna Lénárd, Attila Szendrői, Gábor Rudas, Ildikó Kalina, Bence Fejér, József Szabó, Szabolcs Takács, and Péter Nyirády

Összefoglaló. Bevezetés: A prosztatarák diagnosztikájában az utóbbi években paradigmaváltás történt. Az MR-vizsgálat fejlődése lehetővé tette a prosztatatumor gyanús elváltozásainak célzott mintavételét. Az mpMR fúziós biopszia pontos és költséghatékony módszer. Célkitűzés: Célkitűzésünk az volt, hogy összegezzük az mpMR fúziós biopsziák terén szerzett tapasztalatainkat. Módszer: A Semmelweis Egyetem Urológiai Klinikáján 2017 és 2019 között 40, mpMR fúziós biopsziát végeztünk a BioJet-program segítségével, transperinealis behatolásból. Az MR-vizsgálatok kiértékelése a PI-RADS v2 ajánlása szerint történt. Megvizsgáltuk, hogy a laesiók PI-RADS-besorolása, elhelyezkedése, mérete, az extraprosztatikus terjedés jeleinek megléte, a páciensek PSA-, illetve PSAD-értékei, valamint a prosztata volumene befolyásolja-e a mintavételek kimenetelét. Eredmények: A célzott mintavételek során pácienseink 80%-ánál igazolódott malignitás. PI-RADS 5. és 4. besorolású laesiók esetén a detektációs ráta 91%, illetve 85%, míg PI-RADS 3. laesióknál 20% volt. A perifériás zóna elváltozásainál szignifikánsan magasabb volt a pozitív eredmény valószínűsége, mint a tranzicionális zóna laesióinál (khi2(1) = 6,555, p = 0,010, Fisher-féle egzakt p = 0,017, V = 0,355). Az extraprosztatikus terjedés jelei és a magasabb PSAD-értékek növelték a pozitív minták valószínűségét (khi2(1) = 7,704, p = 0,006, Fisher-féle egzakt p = 0,004, V = 0,355; illetve 0,47 ± 0,50 ng/ml2 vs. 0,18 ± 0,17 ng/ml2; Z = 3,447, p<0,001), míg az elváltozások mérete nem befolyásolta a kimenetelt. A prosztatavolumen szignifikánsan magasabb volt azoknál, akiknél nem igazolódott malignitás (50,9 ± 18,8 ml vs. 119,6 ± 91,6 ml; Z = –3,505, p<0,001). Következtetések: Az elvégzett fúziós biopsziák detektációs rátája magasabb volt az irodalmi átlagnál. Eredményeink alapján a mintavételek kimenetelét befolyásolhatja az elváltozások PI-RADS-besorolása, elhelyezkedése, az extraprosztatikus terjedés, a PSAD-értékek, valamint a prosztatatérfogat. A fenti szempontok figyelembevételével kiválaszthatók azok a páciensek, akik a legtöbbet profitálhatnak a beavatkozásból. Orv Hetil. 2020; 161(52): 2188–2194.

Summary. Introduction: The past decade has seen some major changes in the diagnostics of prostate cancer. Progress in MR imaging has allowed us to better visualise prostate cancer and thus perform targeted biopsies of tumour suspect lesions. mpMRI-ultrasound fusion-guided prostate biopsy is a precise and cost-effective method to diagnose prostate cancer. Objective: The purpose of this study was to summarise our results in mpMRI-ultrasound fusion biopsy between 2017 and 2019 and compare them with the findings in the current literature. Method: Between 2017 and 2019, fully 40, mpMRI-ultrasound fusion biopsies were performed transperineally using the BioJet fusion system at Semmelweis University Urology Clinic. The MRI evaluations were done in line with the PI-RADS v2 guidelines. It was analysed whether the PI-RADS score, the location of the tumour, lesion size, the signs of extraprostatic extension, PSA/PSAD density and prostate volume have an influence on the outcome of mpMRI-ultrasound fusion biopsy. Results: Prostate cancer was diagnosed in 80% of the cases during targeted biopsies. The detection rate was 91%, 85%, and 20% for PI-RADS 5, 4 and 3 lesions, respectively. The detection rate was significantly higher for lesions located at the peripheral zone compared to the ones in the transitional zone (khi2(1) = 6.555, p = 0.010, Fisher-exact p = 0.017, V = 0.355). Signs of extraprostatic extension and higher PSAD correlated with better detection rate (khi2(1) = 7.704, p = 0.006, Fisher-exact p = 0.004, V = 0.355; and 0.47 ± 0.50 ng/ml2 vs. 0.18 ± 0.17 ng/ml2; Z = 3.447, p<0.001, respectively). The size of the lesions did not influence the outcome. The analysis showed a significant correlation between large prostate volumes and negative biopsies (50.9 ± 18.8 ml vs. 119.6 ± 91.6 ml; Z= –3.505, p<0.001). Conclusions: The detection rate of prostate cancer with targeted biopsies was higher than the data found in the international literature. The PI-RADS score, the location of the tumour, MRI signs of extraprostatic extension, PSAD and prostate volume had an influence on the detection rate. Our findings may promote a better selection of the best candidates for targeted biopsies in the future. Orv Hetil. 2020; 161(52): 2188–2194.

Open access
Journal of Behavioral Addictions
Authors: Máté Kapitány-Fövény, Róbert Urbán, Gábor Varga, Marc N. Potenza, Mark D. Griffiths, Anna Szekely, Borbála Paksi, Bernadette Kun, Judit Farkas, Gyöngyi Kökönyei, and Zsolt Demetrovics

Abstract

Background and aims

Due to its important role in both healthy groups and those with physical, mental and behavioral disorders, impulsivity is a widely researched construct. Among various self-report questionnaires of impulsivity, the Barratt Impulsiveness Scale is arguably the most frequently used measure. Despite its international use, inconsistencies in the suggested factor structure of its latest version, the BIS-11, have been observed repeatedly in different samples. The goal of the present study was therefore to test the factor structure of the BIS-11 in several samples.

Methods

Exploratory and confirmatory factor analyses were conducted on two representative samples of Hungarian adults (N = 2,457; N = 2,040) and a college sample (N = 765).

Results

Analyses did not confirm the original model of the measure in any of the samples. Based on explorative factor analyses, an alternative three-factor model (cognitive impulsivity; behavioral impulsivity; and impatience/restlessness) of the Barratt Impulsiveness Scale is suggested. The pattern of the associations between the three factors and aggression, exercise, smoking, alcohol use, and psychological distress supports the construct validity of this new model.

Discussion

The new measurement model of impulsivity was confirmed in two independent samples. However, it requires further cross-cultural validation to clarify the content of self-reported impulsivity in both clinical and nonclinical samples.

Open access