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Community Ecology
Authors:
Z. Kemencei
,
R. Farkas
,
B. Páll-Gergely
,
F. Vilisics
,
A. Nagy
,
E. Hornung
, and
P. Sólymos

We determined microhabitat associations for 39 land snail species based on multimodel inference and generalized linear mixed models using a comprehensive and micro-scale data set from the Aggtelek Karst Area, Hungary. Patterns of microhabitat associations were highly nested among microhabitat types (litter, live trees, dead wood, rock) with high number of specialist species in dead wood and in rock microhabitats. Species composition was highly predictable in these microhabitats as opposed to live tree and litter faunas. Species richness was affected by microhabitat, topographic factors and local moisture conditions. Species richness in dead wood and rock microhabitats remained high irrespective of the topographic effects as opposed to litter and live tree microhabitats, where richness decreased with drier microhabitat conditions due to topography. Our results imply that consideration of topographic factors and microhabitat quality as part of coarse filter conservation measures could be beneficial to local land snail populations in the face of changing climate and disturbance regimes.

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Grassland ecosystems in the Carpathian Basin may be particularly vulnerable to current and predicted changes in precipitation, and ecosystem responses to potential effects of water are not well understood. To examine how water addition can affect the species composition and structure, and CO 2 -flux of a Central European natural steppe plant community, grassland monoliths were irrigated for three consecutive years at Gödöllő, from 2002 through 2004. The loess grassland studied by ex situ is a characteristic plant association of Hungary and similar vegetation can be found in other temperate regions. The treatment consisted of spray irrigation during night-time only in the growing season as well as aboveground biomass removal twice per year. Interannual and intraannual dynamics of species richness, Shannon Diversity, percentage cover, and different functional groups (monocots/dicots; plant life forms; social behaviour types; C 4 /C 3 plants), and Net Ecosystem CO 2 Exchange in treated and untreated permanent plots, were studied simultaneously. To measure NEE and water vapour at stand level a self-developed, portable, non-destructive open chamber system (d=60cm) was used. The majority of the examined parameters varied considerably among years at both irrigated and control, but concerning carbon fluxes water addition effects were evident in dry periods only. At the treated plots, in general species richness, Shannon Diversity, the number of plant life forms and social behaviour types, the ratio of dicots and C 4 plants declined with addition of water. Our study proved that decline in species richness and Shannon diversity is not necessarily followed by the reduction of stand physiological (synphysiological) processes.

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Abstract

Aims: We investigated the influence of body mass index (BMI) on the prevalence of responder status in chronic heart failure patients after cardiac resynchronization therapy (CRT).

Methods: Data on 169 patients with resynchronization therapy were analyzed. Patients were categorized on the basis of the BMI measured at device implantation according to the WHO classification, as normal (BMI: 18.5–24.9 kg/m2), overweight (BMI: 25–29.9 kg/m2) or obese (BMI:≥30 kg/m2). Patients were considered responders if left ventricular ejection fraction was increased by at least 5% at 6-month follow-up.

Results: The mean age in the study population was 60.9±10.86 years (females 29%). The BMI subgroups did not exhibit any significant differences in baseline characteristics (age, gender, left ventricular ejection fraction or NYHA class). Elevated BMIs were associated with higher prevalence of responder status (overweight: 71.4%, obese: 63.0%) relative to subjects with a normal BMI (44.7%) (p=0.015).

Conclusions: In this CRT population, overweight status was associated with a more favorable response to CRT, indicating that the response may possibly be influenced by factors other than those directly related to the heart status or the technical details of the CRT.

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The mediodorsal prefrontal cortex (mdPFC) is a key structure of the central glucose-monitoring (GM) neural network. Previous studies indicate that intracerebral streptozotocin (STZ) microinjection-induced destruction of local chemosensory neurons results in feeding and metabolic alterations. The present experiments aimed to examine whether STZ microinjection into the mdPFC causes metabolic deficits. To do so, glucose tolerance test (GTT) and measurements of plasma metabolites were performed in STZ-treated or control rats. Intraperitoneal D-glucose load was delivered 20 min or 4 weeks following the intracerebral microinjection of STZ or saline (acute or subacute GTT, respectively). The STZ-treated rats displayed acute glucose intolerance: at the 120th min of the test, blood glucose level of these rats was significantly higher than that of the ones in the control group. When determining the plasma level of various metabolites, 30 min following the intracerebral STZ or saline microinjection, the triglyceride concentration of the STZ-treated rats was found to be reduced compared with that of the control rats. The GM neurons of the mdPFC are suggested to be involved in the organization of complex metabolic processes by which these chemosensory cells contribute to adaptive control mechanisms of the maintenance of homeostasis.

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Acta Alimentaria
Authors:
Sz. Luzics
,
Á. Tóth
,
T. Barna
,
E. Szabó
,
I. Nagy
,
B. Horváth
,
I. Nagy
,
Z. Varecza
,
I. Bata-Vidács
, and
J. Kukolya

Abstract

Thermobifida alba is the mesophilic member of the Thermobifida genus, the genome and enzyme sets of which have not been described and published yet. Thermobifida strains are thermotolerant actinomycete, which possess wide sets of cellulose and hemicellulose hydrolysing enzymes. Previously, three endomannanases (Man5ATh, Man5ATc, and Man5AThf) of thermobifidas were cloned and investigated, and hereby the endomannanase of T. alba DSM 43795 is described. All four endomannanases belong to the glycoside hydrolase family 5, their sizes are around 50–55 kDa. Their structure consists of a catalytic domain and a carbohydrate binding module, while there is an interdomain linker region in-between consisting repetitive tetrapeptide motifs (eg.: PPTEPTD-Ta, PTDP-Tc, TEEP-Tf, DPGT-Th). The pH optima of Man5A enzymes from T. alba, Thermobifida halotolerans, Thermobifida cellulosilytica, and Thermobifida fusca are slightly different (6.5, 7.0, 7.5, and 8.0, respectively), however, the temperature optima of the enzymes were detected within a wider range of 65–75 °C. In this research, Man5ATa exhibited the lowest Michaelis-Menten constant (KM) (0.13 mM) on LBG-mannan substrate, while others shared similar kinetic parameters: 0.9–1.7 mM of KM. Despite the high sequence similarity of the investigated mannanases, they exhibit different temperature stability parameters. These different functional characteristics can be advantageous for industrial applications producing biologically active, oligomannan prebiotics under different conditions.

Open access

A tápláltsági állapot bioimpedancia-alapú meghatározásának lehetősége a rehabilitációban

Possibility of bioimpedance-based nutritional status assessment in rehabilitation

Orvosi Hetilap
Authors:
Babett Tóth
,
Dóra Terjék
,
Rebeka Nagy-Kónya
, and
Zoltán Dénes

Összefoglaló. Bevezetés: Még nem rendelkezünk olyan malnutritiodiagnosztikai módszerrel, amellyel a rehabilitációs intézetek betegeinek tápláltsági állapotát és annak változását objektív, pontos, reprodukálható módon követni tudjuk. Célkitűzés: A vizsgálat célja az Országos Orvosi Rehabilitációs Intézet pácienseinek malnutritiorizikó-szűrése mellett a bioimpedancia-alapú testösszetétel meghatározása a megfelelő táplálás kialakítása érdekében. Módszer: Malnutritiorizikó-szűrésre a Nutrition Risk Screening 2002 kérdőívet használtuk. A testösszetétel-analizálást a multifrekvenciás bioimpedancia-alapú seca mBCA 525 készülékkel végeztük. Eredmények: 41 beteg felvételt követő, validált szűrőmódszerrel mért malnutritiorizikójának összefüggése a testtömegindexszel való evidens kapcsolatához (r = –0,662, p<0,001) képest gyengült a zsírmentes testtömegindexszel (r = –0,487, p = 0,001) és a vázizomtömeggel (r = –0,476, p = 0,002). A malnutritiorizikó a zsírtömeggel nem mutatott korrelációt. A testtömegindex erős összefüggései a testösszetétellel agysérültek esetében lényegesen gyengültek. A vázizom- és a zsírtömeg között erős összefüggést tapasztaltunk valamennyi esetben. A testtömegindex csak agysérültek esetén mutatott összefüggést az extracelluláris és a teljes testvíz arányával. A vízterek minden esetben erős összefüggést prezentáltak a fázisszöggel (r = –0,711, p<0,001). A fázisszög agysérültek esetében mutatta a legerősebb korrelációkat a zsírmentes testtömegindexszel (r = 0,638, p<0,001), valamint a vázizom- (r = 0,544, p<0,001) és zsírtömeggel (r = 0,588, p<0,001). Következtetés: A malnutritiót mérő skálák nem elég szenzitívek a rehabilitációs intézetek betegcsoportjaira, a testtömegindex-kalkulációval pedig kevesebb rizikós beteg szűrhető ki, mint a testösszetétel-mérésekkel. A rehabilitációs kórházak számára alkalmas módszernek tartjuk a szűrés kombinálását bioimpedancia-alapú testösszetétel-analizálással. Orv Hetil. 2022; 163(17): 670–676.

Summary. Introduction: We do not have a diagnostic method for malnutrition yet that can monitor the nutritional status of patients in rehabilitation institutions and its changes in an objective, accurate, reproducible way. Objective: The aim of this study was to determine the risk of malnutrition in patients at the National Institute for Medical Rehabilitation of Hungary completing with bioimpedance-based body composition in order to develop adequate nutrition therapy. Method: The Nutritional Risk Screening 2002 questionnaire was used. Body composition analysis was determined by the multifrequency bioimpedance-based seca mBCA 525 device. Results: The association between the risk of malnutrition measured by a validated screening method of 41 patients was weaker with fat-free mass index (r = –0.487, p = 0.001) and skeletal muscle mass (r = –0.476, p = 0.002) than with body mass index (r = –0.662, p<0.001). It was not correlated with fat mass. Strong correlations of body mass index with body composition were significantly weakened in the case of brain injuries. A strong correlation between skeletal muscle and fat mass was observed in all cases. Body mass index correlated with extracellular and total body water ratio only in the case of brain injuries. The extracellular and total body water ratio presented a strong correlation with the phase angle in each case (r = –0.711, p<0.001). Phase angle showed the strongest correlations with fat-free mass index (r = 0.638, p<0.001), skeletal muscle (r = 0.544, p<0.001) and fat mass (r = 0.588, p<0.001) in the case of brain-injured patients. Conclusion: Malnutrition screening tools are not sensitive enough for patient groups of rehabilitation institutions, and with body mass index, less risky patients can be screened out than with body composition analysis. Combining screening with bioimpedance-based body composition analysis is a suitable method for rehabilitation hospitals. Orv Hetil. 2022; 163(17): 670–676.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
E. Kuzmann
,
S. Stichleutner
,
Z. Homonnay
,
A. Vértes
,
A. Paszternák
,
F. Nagy
,
I. Felhősi
,
G. Pető
,
J. Telegdi
, and
E. Kálmán

Abstract  

Thin films prepared by vacuum evaporation of 57Fe and subsequent low energy ion implantation were investigated by conversion electron Mössbauer spectroscopy and AFM measurements. A sextet with Mössbauer parameters of δ = 0.1 mm/s and B = 26 T appearing in the CEM spectra was identified as amorphous iron. Passivation and phosphonation of the thin films revealed the high affinity of amorphous iron in chemical reactions.

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Acta Alimentaria
Authors:
R. Tömösközi-Farkas
,
Zs. Polgár
,
M. Nagy-Gasztonyi
,
V. Horváth
,
T. Renkecz
,
K. Simon
,
F. Boross
,
Z. Fabulya
, and
H. Daood

Anti-nutritive components in multi resistant potato cultivars were investigated in relation to conventional and organic farming for three years. Glycoalkaloids, nitrate, nitrite, asparagine, and glutamine contents of tubers were examined. Farming technology was found not to have an effect on the level of glycoalkaloids, which was influenced mostly by the genotype and season. Nitrogen fertilisation caused significant increase in nitrate, asparagine, and glutamine contents as compared to organic farming. Nitrite content was found to be more independent of farming technologies than nitrate. Tubers of cultivar Rioja had the lowest nitrate content irrespective of season or technology. In conclusion, the absolute amount and changes of different anti-nutritive components of potato tubers were influenced differently by the technology, genotype, and season in a complex manner. Organic farming had no effect on the glycoalkaloid content, but the nitrate levels had a tendency to be lower compared to conventional farming. This can be seen as a positive effect of organic farming.

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Acta Physiologica Hungarica
Authors:
H. Pikó
,
V. Vancsó
,
B. Nagy
,
J. Balog
,
M. Nagymihály
,
A. Herczegfalvi
,
L. Tímár
,
Z. Bán
, and
V. Karcagi

Muscular dystrophies are a genetically heterogeneous group of degenerative muscle disorders. This article focuses on two severe forms of muscular dystrophies and provides genetic data for a large cohort of Hungarian patients diagnosed within the last few years by the authors.The Duchenne/Becker muscular dystrophy (DMD/BMD) is caused by mutations in the dystrophin gene, which is located on chromosome Xp21. The genetic analysis of dystrophin is usually performed by multiplex polymerase chain reaction (PCR), which detects approximately 95% of all deletions but does not distinguish between one and two copies of the exons investigated. The present work, therefore, concentrates on the improvement of the diagnostic panel for the analysis of DMD/BMD in Hungary. Radioactively labelled cDNA probes, encompassing the whole dystrophin gene detect all the deletions and the analysis is quantitative. In addition, the new multiple ligationdependent probe amplification (MLPA) technique was recently introduced that enabled more reliable and faster quantitative detection of the entire dystrophin gene. The genomic basis of facioscapulohumeral muscular dystrophy (FSHD) is associated with contraction of the D4Z4 repeat region in the subtelomere of chromosome 4q. In case of FSHD, molecular genetic criteria still have to be improved because of the complexity of the disorder.

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