The influence of spatial pulsed magnetic field application on neuropathic pain after tibial nerve transection in rat

The purpose of the study was to examine the influence of the spatial variable magnetic field (induction: 150–300?µT, 80–150?µT, 20–80?µT; frequency 40?Hz) on neuropathic pain after tibial nerve transection. The experiments were carried out on 64 male Wistar C rats. The exposure of animals to magnetic field was performed 1?d/20?min., 5?d/week, for 28?d. Behavioural tests assessing the intensity of allodynia and sensitivity to mechanical and thermal stimuli were conducted 1?d prior to surgery and 3, 7, 14, 21 and 28?d after the surgery. The extent of autotomy was examined. Histological and immunohistochemical analysis was performed. The use of extremely low-frequency magnetic fields of minimal induction values (20–80?µT/40?Hz) decreased pain in rats after nerve transection. The nociceptive sensitivity of healthy rats was not changed following the exposition to the spatial magnetic field of the low frequency. The results of histological and immunohistochemical investigations confirm those findings. Our results indicate that extremely low-frequency magnetic field may be useful in the neuropathic pain therapy.     

Plant ubiquitylation and proteolytic systems, the key elements in hormonal signaling pathways

The general function of the ubiquitylation systems is to conjugate ubiquitin to lysine residues within substrate proteins, thus targeting them for degradation by the proteasome. In Arabidopsis thaliana more than 1300 genes (approximately 5% of the proteome) encode components of the ubiquitin/26S proteasome pathway. Approximately 90% of these genes encode subunits of the E3 ubiquitin ligases, which confer substrate specificity to the ubiquitin/26S proteasome pathway. The plant E3 ubiquitin ligases comprise a large and diverse family of proteins or protein complexes containing either a HECT domain, a RING-finger or U-box domain. The SCF class of E3 ligases is the most thoroughly studied in plants because some of them participate in regulation of hormone signaling pathways. The role of the SCF is to ubiquitylate repressors of hormone response (auxin, gibberellins), whereas in response to ethylene, abscisic acid and brassinosteroids the SCF participate in degradation of positive regulators in the absence of the hormone.     

Combined effect of low-power laser irradiation and anthraquinone anticancer drug aclarubicin on survival of immortalized cells: Comparison with mitoxantrone

The photodynamic response of the anthraquinone anticancer drug aclarubicin (ACL) was investigated in vitro and compared with that of mitoxantrone (MTX). Cultured immortalized rodent B14 and NIH 3T3 cells were used in the experiments as a model for cells with neoplastic phenotype. Long-term cytotoxicity and inhibition of cell proliferation assayed by the clonal growth and MTT-tetrazolium methods were estimated to compare the efficacy of aclarubicin and mitoxantrone in photosensitizing cells and their death after non-thermal exposure to monochromatic laser light. Green He-Ne (543.5 nm) or red semiconductor (670 nm) low-power laser (LPL) irradiations were applied. Different dose-responses of both cell lines to aclarubicin and mitoxantrone were found so that the cytotoxicity of MTX was considerably greater than the cytotoxicity of ACL. Phototherapy response (P < 0.0001) was observed only for B14 cells after sensitisation with aclarubicin. Under the same conditions no significant effect of red light irradiation (semiconductor 670 nm laser) on survival of both cell lines treated with mitoxantrone was found.     

Phylogeographic patterns of steppe species in Eastern Central Europe: a review and the implications for conservation

The phylogeography of species associated with European steppes and extrazonal xeric grasslands is poorly understood. This paper summarizes the results of recent studies on the phylogeography and conservation genetics of animals (20 taxa of beetles, butterflies, reptiles and rodents) and flowering plants (18 taxa) of such, "steppic" habitats in Eastern Central Europe. Most species show a similar phylogeographic pattern: relatively high genetic similarity within regional groups of populations and moderate-to-high genetic distinctiveness of populations from currently isolated regions located in the studied area. This distinctiveness of populations suggests a survival here during glacial maxima, including areas north of the Bohemian Massif-Carpathians arc. Steppic species generally do not follow the paradigmatic patterns known for temperate biota (south-north “contraction–expansion”), but to some extent are similar to those of arctic-alpine taxa. There are three main groups of taxa within Eastern Central Europe that differ in their contemporary distribution pattern, which may reflect historical origin and expansion routes. Present diversity patterns of the studied steppic species suggest that they share a unique genetic signature and distinct assemblages exist in each of the now isolated areas rich in steppic habitats. At least some of these areas probably act as present “interglacial refugia” for steppic species. This study strongly supports the need to protect steppic species throughout their entire ranges in the region, as the continuous destruction of steppic habitats in some areas may lead not only to the disappearance of local populations, but also to the extinction of unique evolutionary units.     

The genetic basis of graves' disease

The presented comprehensive review of current knowledge about genetic factors predisposing to Graves' disease (GD) put emphasis on functional significance of observed associations. In particular, we discuss recent efforts aimed at refining diseases associations found within the HLA complex and implicating HLA class I as well as HLA-DPB1 loci. We summarize data regarding non-HLA genes such as PTPN22, CTLA4, CD40, TSHR and TG which have been extensively studied in respect to their role in GD. We review recent findings implicating variants of FCRL3 (gene for FC receptor-like-3 protein), SCGB3A2 (gene for secretory uteroglobin-related protein 1- UGRP1) as well as other unverified possible candidate genes for GD selected through their documented association with type 1 diabetes mellitus: Tenr-IL2-IL21, CAPSL (encoding calcyphosine-like protein), IFIH1(gene for interferon-induced helicase C domain 1), AFF3, CD226 and PTPN2. We also review reports on association of skewed X chromosome inactivation and fetal microchimerism with GD. Finally we discuss issues of genotype-phenotype correlations in GD.     

Species–area relationships of butterflies in Europe and species richness forecasting

Species–area relationships (SARs) of European butterfly species (Rhopalocera) appear to follow power functions with Mediterranean butterflies having a much higher slope value (z=0.49) compared to the slope for the northern and eastern European countries (z=0.10). A simulated process of species extinction by a stepwise density dependent random elimination of species affected species–area patterns differently. For Mediterranean countries SAR slopes decreased, for other European countries slopes increased during the extinction process. Comparisons of species numbers before and after extinction with those predicted by a classical SAR approach differed widely and revealed that SARs are not able to predict future species numbers at local scales. For Mediterranean countries the classical SAR approach underestimated the number of species remaining after simulated extinction, for all other European countries SARs highly overestimated species numbers. These contrasting patterns indicate that changes in SAR patterns do not unequivocally point to changes in species diversity or community structure as assumed by current theory. On the other hand, the results strongly indicate that simplified applications of SARs for forecasting might give misimpressions about species loss and future biodiversity if the initial community structure, especially relative densities and numbers of species with restricted range size, are not taken into account.     

Antifungal activity of biflavones from Taxus baccata and Ginkgo biloba

Bilobetin and 4'-O-methylamentoflavone were isolated and identified in the needles of Taxus baccata, for the first time in this species. The antifungal activity of biflavones from T. baccata and Ginkgo biloba, namely amentoflavone, 7-O-methylamentoflavone, bilobetin, ginkgetin, sciadopitysin and 2,3-dihydrosciadopitysin towards the fungi Alternaria alternata, Fusarium culmorum, Cladosporium oxysporum was determined employing computer-aided image analysis couplet to a microscope. Bilobetin exhibited a significant antifungal activity with values of ED50 14, 11 and 17 microM respectively. This compound completely inhibited the growth of germinating tubes of Cladosporium oxysporum and Fusarium culmorum at a concentration 100 microM. Activity of ginkgetin and 7-O-methylamentoflavone towards Alternaria alternata was stronger than that of bilobetin. Moreover, slight structural changes in the cell wall of Alternaria alternata exposed to ginkgetin at concentration of 200 microM were observed.     

The effects of garlic-derived sulfur compounds on cell proliferation, caspase 3 activity, thiol levels and anaerobic sulfur metabolism in human hepatoblastoma HepG2 cells

The aim of the present studies was to determine whether the mechanism of biological action of garlic-derived sulfur compounds in human hepatoma (HepG2) cells can be dependent on the presence of labile sulfane sulfur in their molecules. We investigated the effect of allyl sulfides from garlic: monosulfide, disulfide and trisulfide on cell proliferation and viability, caspase 3 activity and hydrogen peroxide (H(2)O(2)) production in HepG2 cells. In parallel, we also examined the influence of the previously mentioned compounds on the levels of thiols, glutathione, cysteine and cysteinyl-glycine, and on the level of sulfane sulfur and the activity of its metabolic enzymes: rhodanese, 3-mercaptopyruvate sulfurtransferase and cystathionase. Among the compounds under study, diallyl trisulfide (DATS), a sulfane sulfur-containing compound, showed the highest biological activity in HepG2 cells. This compound increased the H(2)O(2) formation, lowered the thiol level and produced the strongest inhibition of cell proliferation and the greatest induction of caspase 3 activity in HepG2 cells. DATS did not affect the activity of sulfurtransferases and lowered sulfane sulfur level in HepG2 cells. It appears that sulfane sulfur containing DATS can be bioreduced in cancer cells to hydroperthiol that leads to H(2)O(2) generation, thereby influencing transmission of signals regulating cell proliferation and apoptosis.