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Adult fly collections were made in May and August 2006, from the mud of a salty lake in the Kiskunság National Park, Hungary. We collected 21,600 individuals of 62 species in May and 18,400 individuals of 81 species in August, giving a total of 103 species (only 40 appearing in both seasons). Dominant species were different in the two collections. Five species are new for the Hungarian fauna. Diversity measured by several indices was higher in the May collection. We observed simultaneously a nearly lognormal distribution and a power-law like behaviour of the abundances.

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It is an essential property of diversity indices that increases in the abundance or frequency of the most frequent species result in a decline in diversity, whereas increases in the abundance of the rarest species lead to an increase in diversity. At the same time, without resort to mathematical operations, it is difficult to determine the sign and measure of alteration in diversity when increasing an additional frequency while leaving all others unaltered. A more concrete task is to determine the index response to a partial alteration of fixed percentage in the frequencies of the multi-species community or collection. Plotting the observed responses or sensitivity values against the frequencies concerned makes possible a good overview of the sensitivity relations. The mathematical groundwork of sensitivity analysis with respect to diversity indices has already been elaborated. To date, however, the methodological possibilities engendered by such analyses have yet to be exploited. In the present work, sensitivity relations are discussed for apple-bait Drosophilidae collections and human faeces trap collections of flies inhabiting brook valleys in the low mountains of Hungary. Inspection of the results enables us to identify the range of frequencies at which significant increases or decreases in diversity will result. A relatively small increase of so-called nearly indifferent or quasineutral frequencies lying within that frequency range has a trivial influence on diversity values. While sensitivity is astonishingly sizeable with a few dominant case numbers, all other frequencies scarcely influence the index value.

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Rats were treated with a combination of insecticide agents in different timing schemes. In acute administration, 1/5 LD50 of the three insecticides: dimethoate, propoxur and cypermethrin, or their combination, was given once by gavage. In the developmental model, female rats received oral doses of 1/25 LD50 of the above insecticides in combination in three timing schemes including pregnancy and lactation. Responses in the somatosensory cortex and in the tail nerve, evoked by peripheral electric stimulation, were recorded in acute preparation under urethane anesthesia. It was tested whether the parameters of the cortical and peripheral evoked response are dependent on the frequency and whether this dependence is different in control and treated animals. The latency increase of the cortical responses with increasing stimulation frequency was significantly stronger in rats treated acutely with cypermethrin and the combination, and in rats receiving the combination during both intra- and extrauterine development. On the duration, the effects were less clear. Frequency dependent increase of the tail nerve action potential latency was significantly intensified by cypermethrin, and the amplitude decrease, by cypermethrin and dimethoate. Fatigue of this response during a stimulation series was also altered by the insecticides. Frequency dependence and fatigue possibly reflect the actual state of the nervous system and may have the potency to be developed to functional biomarkers.

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This paper presents the phytosociological description of a drained swamp community, Veratro albi-Fraxinetum angustifoliae, so far found only in the Nyírség at Nyírábrány “Kis-kőrises”, “Mogyorósi-erdő”; Vámospércs “Jónásrész-Kőrises”; and Vámospércs “Jónásrész-Buzita”. The habitat of the community is transitional between that of alder swamps (Fraxino pannonicae-Alnetum glutinosae), and hardwood riparian forests (Fraxino pannonicae-Ulmetum). The community is characterised by high proportions of character species of Alnion glutinosae and Molinion coerulei as well as Quercetea pubescentis-petraeae s. l. whereas character species of the order Fagetalia are almost completely absent. It hosts several rare, often threatened species, such as Angelica palustris, Ophioglossum vulgatum, Trollius europaeus and Veratrum album.

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Acta Biologica Hungarica
Authors: L. G. Puskás, L. Tiszlavicz, Zs. Rázga, L. L. Torday, T. Krenács and J. Gy. Papp

Recent and historical evidence is consistent with the view that atherosclerosis is an infectious disease or microbial toxicosis impacted by genetics and behavior. Because small bacterial-like particles, also known as nanobacteria have been detected in kidney stones, kidney and liver cyst fluids, and can form a calcium apatite coat we posited that this agent is present in calcified human atherosclerotic plaques. Carotid and aortic atherosclerotic plaques and blood samples collected at autopsy were examined for nanobacteria-like structures by light microscopy (hematoxylin-eosin and a calcium-specific von Kossa staining), immuno-gold labeling for transmission electron microscopy (TEM) for specific nanobacterial antigens, and propagation from homogenized, filtered specimens in culture medium. Nanobacterial antigens were identified in situ by immuno-TEM in 9 of 14 plaque specimens, but none of the normal carotid or aortic tissue (5 specimens). Nanobacteria-like particles were propagated from 26 of 42 sclerotic aorta and carotid samples and were confirmed by dot immunoblot, light microscopy and TEM. [3H]L-aspartic acid was incorporated into high molecular weight compounds of demineralized particles. PCR amplification of 16S rDNA sequences from the particles was unsuccessful by traditional protocols. Identification of nanobacteria-like particles at the lesion supports, but does not by itself prove the hypothesis that these agents contribute to the pathogenesis of atherosclerosis, especially vascular calcifications.

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The in vitro antifungal activity of different statins and the combinations of the two most effective ones (fluvastatin and rosuvastatin) with amphotericin B were investigated in this study on 6 fungal isolates representing 4 clinically important genera, namely Absidia, Rhizomucor, Rhizopus and Syncephalastrum . The antifungal effects of statins revealed substantial differences. The synthetic statins proved to be more effective than the fungal metabolites. All investigated strains proved to be sensitive to fluvastatin. Fluvastatin and rosuvastatin acted synergistically and additively with amphotericin B in inhibiting the fungal growth in clinically available concentration ranges. Results suggest that statins combined with amphotericin B have a therapeutic potential against fungal infections caused by Zygomycetes species.

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The mortality rates of fungal infections that affect the central nervous system are high in consequence of the absence of effective antifungal drugs with good penetration across the blood-brain barrier and the blood-cerebrospinal fluid barrier. In the present work in vitro antifungal activities of three good penetrating non-antifungal drugs (amantadine hydrochloride, R-(-)-deprenyl hydrochloride, valproic acid sodium salt) and their combinations with three antifungal agents (amphotericin B, itraconazole, terbinafine) were tested with broth microdilution method against eight fungal isolates belonging to Zygomycetes (Lichtheimia corymbifera, Rhizomucor miehei, Rhizopus microsporus var. rhizopodiformis, Saksenaea vasiformis) and Aspergillus genus (A. flavus, A. fumigatus, A. nidulans, A. terreus). These are known to be possible agents of central nervous fungal infections (CNFI). When used alone, the investigated nonantifungal drugs exerted slight antifungal effects. In their combinations with antifungal agents they acted antagonistically, additively and synergistically against zygomyceteous isolates. Primarily antagonistic interactions were revealed between the investigated drugs in case of Aspergilli, but additive and synergistic interactions were also observed. The additive and synergistic combinations allowed the usage of reduced concentrations of antifungal agents to inhibit the fungal growth in our study. These combinations would be a basis of an effective, less toxic therapy for treatment of CNFI.

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The neurotoxic effect of amyloid-beta peptide (1-42) was investigated in cultures of neuronal tissue derived from the basal forebrain of embryonic rat. The axonal varicosities of the cholinergic cells were revealed by vesicular acetylcholine transporter staining, and the axonal varicosities in general by synaptophysin immunohistochemistry. The results demonstrate that the treatment of in vitro neuronal cultures with 20 mM amyloid-beta peptide (1-42) for 2 days on day 5, 12 or 15 exerted a neurotoxic effect on both the cholinergic and the non-cholinergic neurons. In the same cultures, the absolute number of synaptophysin-positive axon varicosities was reduced to greater extent (control: 203 ± 37/field vs treated: 101 ± 16/field) than the number of vesicular acetylcholine transporter-immunoreactive (control: 48 ± 4/field vs treated: 0/field) structures. It is concluded that amyloid-beta peptide (1-42) does not have a specific effect only on the cholinergic neurons, but affects non-cholinergic neurons as well.

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The aim of the present study was to identify gene expression changes in the rapid cardiac pacing-induced delayed antiarrhythmic protection in the canine, using cDNA microarrays and quantitative real-time PCR (QRT -PCR) techniques. In all dogs under light pentobarbitone anaesthesia, a pacing electrode was introduced into the right ventricle, and then the animals were divided into three groups: (1) sham-operated and sham-paced group (SP, n = 3) (2) ischaemic control group (IC; n = 3); these were without cardiac pacing and subjected only to a 25 min occlusion of the left anterior descending coronary artery (LAD), and (3) paced group (PC, n = 3); these animals were paced at a rate of 220–240 beats min−1 24 h prior to ischaemia. With cDNA chip 23 genes were found with altered expression in response to rapid cardiac pacing and 10 genes in the IC group when compared to SP dogs. These genes encode transcription factors (MEF2); members of signaling pathways (TGFβ2, PDE4D9), hormone related proteins (e.g. vasopressin V1 and V2 receptors). RT-QPCR was used either to confirm the results of the microarray analysis and also to study 46 genes which are already known to have a role in the late phase of PC. By this method 17 genes were up-regulated and 6 genes down-regulated in the IC group; their expression ratios changed either to the opposite or showed no alteration after cardiac pacing. This study would add some new information about those transcriptional changes that are involved in the delayed phase of cardiac protection.

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Acta Biologica Hungarica
Authors: L. Institóris, Dóra Kovács, I. Kecskeméti-Kovács, Anita Lukács, Andrea Szabó, Zsuzsanna Lengyel, A. Papp, L. Nagymajtényi and I. Dési

Detectable interactions between NOEL (No Observed Effect Level) doses of Pb, Hg and Cd in general toxicological, hematological, and immune function parameters were investigated. The metals (Pb-acetate, 20 mg/kg; HgCl2, 0.40 mg/kg; CdCl2, 1.61 mg/kg) were combined. First, the rats received the combination Pb+Hg+Cd for 4 weeks per os. Significant difference vs. control was found only in the weight of lung and popliteal lymph node (PLN). The Pb+Hg and Pb+Cd combinations significantly decreased the PLN to 100 g body weight and PLN to brain weight ratio, and Pb+Hg also decreased the relative adrenal weight. After 12 weeks treatment with the same doses, effects on the thymus, kidney, and adrenal weights in the Pb+Hg, and thymus weight in the Pb+Cd, combination were seen. Pb+Cd also affected the white and red blood cell count and hematocrit. Combined with Hg or Cd, NOEL dose Pb showed toxicity, indicating that exposure limits may be inefficient in combined exposure situations.

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