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Community Ecology
Authors:
B. Tajthi
,
R. Horváth
,
Sz. Mizser
,
D. D. Nagy
, and
B. Tóthmérész

Urban areas have been growing radically worldwide, causing considerable changes in biodiversity of natural habitats. In floodplain forests, we studied the effects of urbanization on ground-dwelling spider assemblages along a rural–suburban–urban gradient in Hungary. We tested three traditional hypotheses (intermediate disturbance hypothesis, habitat specialist hypothesis and hygrophilous species hypothesis) and two novel expectations (shade-preferring species hypothesis, and disturbance sensitive species hypothesis) on spiders. We found that the total number of species was higher in the suburban habitat than in rural and urban ones, supporting the intermediate disturbance hypothesis. We found a decrease in the species richness of forest specialist and shade-preferring species along the urbanization gradient. We found that the number of hygrophilous and disturbance sensitive species was the lowest in the urban habitat. The spider assemblages of the rural and suburban habitats were clearly separated from the assemblages of urban habitats. Based on our findings we emphasize that low and moderate intensity of forest management contributes to the preservation of the local species richness in floodplain forests.

Open access

The aim of the study was the identification and characterisation of coagulase-positive Staphylococcus bacteria obtained from food matrices by mass spectrometry and molecular methods. A total of 46 coagulase-positive Staphylococcus isolates were collected from different foodstuffs. The Staphylococcus isolates were identified by MALDI-TOF MS and confirmed by the presence and sequence analysis of the Staphylococcus protein A gene. Staphylococcal enterotoxin genes were also investigated by multiplex PCR. Based on the identification of strains by the MALDI-TOF MS technique and spa-typing, all strains were identified as Staphylococcus aureus. Based on their MS peak profiles, the isolates matched the spectra of three S. aureus reference strains in the Bruker MALDI Biotyper database, with identification scores higher than 1.999 in the case of all 46 (100%) isolates. The isolates showed great genetic variability. Twenty spa types were identified, from which most lineages are capable of colonizing humans. Fifty percent of the strains harboured at least one of four enterotoxin genes (seg, seh, sei, and ser), but none of the classical enterotoxin genes could be detected.

Open access

Summary  

Resection and subsequent end-to-end anastomosis of the windpipe is a tried-and-tested acceptable method for the surgical treatment of segmental defects. There are a variety of different techniques for tracheal end-to-end anastomosis, but controversial reports highlight the fact that the suturing technique of the anastomosis is still subject of debate. We aimed to show the postoperative effects of the continuous and simple interrupted suturing technique respectively on the tracheal cartilage using differential scanning calorimetry. Transsection and subsequent reanastomosis of the cervical trachea was performed in 14 adult beagle dogs. The trachea was anastomized with continuous or simple interrupted sutures respectively depict no change in microcirculation after the resection of the trachea, but significant decrease following the completion the anastomosis with continuous sutures. Conventional histological analysis did not show any marked postoperative change in the tracheal cartilage but our DSC scans clearly demonstrated the differences between the intact cartilages and the ones involved in the anastomosis.

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Journal of Thermal Analysis and Calorimetry
Authors:
G. Bognár
,
Cs. Pintér
,
B. Horváth
,
T. Sydo
,
E. Ligeti
,
J. Pulai
, and
D. Lőrinczy

Abstract  

Osteonecrosis (ON) of the femoral frequently occurs after steroid medication. One of the final pathways leading to steroid induced ON is thought to be pathologic fat metabolism. The pathobiological mechanism underlying the induction of fat metabolism outslides by steroids leading to ON has not been fully elucidated. The purpose of this study was to examine the intraoperative obtained gluteal fat tissue from ON patients with histology, gas chromatography (GC) and differential scanning calorimetry (DSC) and to compare them with otherwise healthy patient’s samples. The histological sections showed no significant differences compared with the control group. GC revealed that fraction of saturated fatty acids decreased in ON samples from mean values of controls of 24% to 21, the polyunsaturated fraction from 20 to 14%. The monounsaturated acids showed an increase from mean rate of 52% of the controls to 65% of steroid treated samples. DSC curves correlate with chromatographic analysis of the tissue fatty acids (Steroid treated, heating between 0–100°C: T m=5.7°C, ΔH= −15.8J/g−1; heating between −20–100°C: Tm= −9.96 and 5.85°C, ΔH= −59.17 and −16.2 J g−1. Non-necrotic, heating between 0–100°C: two separable transition with Tm=5.7 and 9.9°C, total ΔH= −20.8 J g−1; heating between −20–100°C: Tm= −10.9 and 4.95°C, total ΔH= −75.8 J g−1.) Our preliminary findings are rather tendentious. Further investigations are needed with higher sample rate and under other anamnestic circumstances too.

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Journal of Thermal Analysis and Calorimetry
Authors:
Cs. Pintér
,
G. Bognár
,
B. Horváth
,
T. Sydo
,
E. Ligeti
,
J. Pulai
, and
D. Lőrinczy

Abstract  

Avascular necrosis of human femoral head (ANFH) causes incongruity in the joint that leads to disability in patients requires total hip arthroplasty (THA). Several etiological factors of ANFH have been proposed in the literature but there are cases of idiopathic origin. We observed macroscopic variation in quality of the subcutaneous fat tissue in patients with ANFH compared to patients with osteoarthritis or hip fracture during THA procedures. The samples were analysed by histology, gas chromatography (GC) and differential scanning calorimetry (DSC). Conclusion: the alteration in the fatty acid profile did not cause histological changes, however we could detect biochemical changes using DSC and GC.

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Journal of Thermal Analysis and Calorimetry
Authors:
Cs. Pintér
,
G. Bognár
,
B. Horváth
,
T. Sydo
,
E. Ligeti
,
J. Pulai
, and
D. Lőrinczy

Abstract  

The osteonecrosis or avascular necrosis of the antero-superior part of the human femoral head (ANFH) often causes incongruity in the hip joint and leads to severe pain and disability in middle aged patients. This abnormality often requires surgical intervention, mainly total hip arthroplasty (THA). The possible pathomechanisms of ANFH are fat embolism, arterial occlusion, fatty necrosis of osteocytes and intraosseous hypertension. Factors have been proposed in the literature that can lead to this condition are alcohol abuse, steroid therapy, metabolic changes, dyslipidaemia. In some case we can not verify any factor; these are the so called idiopathic ANFH cases. We observed macroscopic variation in colour and consistency of the subcutaneous fat tissue in patients with ANFH compared to osteoarthritis or hip fracture during THA procedures. Subcutaneous fat tissues during THA from a patient with ANFH due to alcohol abuse were compared with an otherwise healthy patient who underwent surgery due to traumatic hip fracture. No histological changes were notified in the size; shape of adipocytes and in the cells of the septae of the connective tissue. Gas chromatography showed that the patient with alcoholic ANFH had less long chain fatty acids. DSC revealed, that in case of non-necrotic sample as a reference, during heating between 0–100°C two separable transitions are with T m=5.7 and 9.9°C, total ΔH= −20.8 J g−1. In −20–100°C range endotherms with T m= −10.9 and 4.95°C, total ΔH= −75.8 J g−1 could be detected. In case of alcohol-induced avascular necrosis we have found endotherms between 0–100°C with: T m=7.3°C, total ΔH= −26.9 J g−1, and heating between −20–100°C: T m= −0.25°C, total ΔH= −103.3 J g−1 thermal parameters. The alteration in the fatty acid profile did not cause histological changes, but we were able to detect it with analytical methods e.g. DSC and gas chromatography.

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Tomatoes (Solanum lycopersicon L.) are one of the most important and most widely consumed vegetables in the world. The fruit contains considerable amount of different phytonutrients such as carotenoids, tocopherols, and vitamin C. In the present work, effects of some abiotic factors on the concentration of phytonutrients were investigated in tomato cultivated in two different types of soil. It was found that the type of soil had slight effect on the most important vital nutrients, while the ecological factors, particularly precipitation and average temperature 3 weeks before harvest, were of significant influence on such nutrients. It was found that low temperature and high precipitation before harvest caused the levels of carotenoids, tocopherol, and vitamin C to significantly increase by 65%, 46%, and 28%, respectively.

Open access
Journal of Thermal Analysis and Calorimetry
Authors:
Zs. Baji
,
Z. Lábadi
,
Z. E. Horváth
,
M. Fried
,
B. Szentpáli
, and
I. Bársony

Abstract

This study on ALD grown ZnO layers is aimed at the systematic study of the effect of incorporation of different Al contents on the properties of the layers. An alternate precursor pulse method was used for layer deposition. Optimal doping was achieved at 210 °C at 2 at% Al content. A relationship between crystalline morphology versus temperature and aluminium incorporation was established.

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Acta Biologica Hungarica
Authors:
Gabriella Fábián
,
B. Tombor
,
Ildikó Németh
,
Emese Kicsi G.
,
Margit Szikszay
,
Gyöngyi Horváth
, and
Mária Szűcs

Morphine was provided to rats in drinking water for 21 days. Profound analgesic tolerance was detected both in hot-plate and tail-flick tests. The density of [3H]DAMGO binding sites increased by 76% in spinal cord membranes due to morphine exposure compared to those in opioid naive animals. Slightly augmented [3H]DAMGO binding was measured in the synaptic plasma membranes, with a concomitant decrease in the microsomal membranes, of morphine tolerant/dependent brains. These observations suggest that the regulation of spinal mu opioid receptors might be different from those in the brain. It is emphasized that the molecular changes underlying tolerance/dependence are influenced by several factors, such as the tissue or subcellular fractions used, besides the obvious importance of the route of drug administration. Results obtained after voluntary morphine intake further support the growing number of experimental data that chronic morphine does not internalize/downregulate the mu opioid receptors in the central nervous system.

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Acta Biologica Hungarica
Authors:
L. Horváth
,
Cs. Székely
,
Zs. Boczonádi
,
E. Mészáros
,
M. Bercsényi
,
B. Urbányi
, and
T. Müller

European eel is a catadromous fish species, which means that after living in freshwater premature individuals adapt to sea water, and migrate to the Sargasso Sea for spawning. Although male eel can be sexually matured even in freshwater, to date, it was believed that female eel can be matured only in seawater. Here we show that the process of sexual maturation may be induced in freshwater by treating female eels with carp pituitary (GSI = 9.87±1.55%). It is thus proposed that seawater condition is not an obligatory environment for stimulating gametogenesis and for artificial maturation of the European eel in neither gender.

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