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951.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Michalska Hassan Y. Aboul‐Enein 《Luminescence》2012,27(6):473-477
The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH?) and hydroxyl radial (HO?). The CATs examined were found to inhibit the ESR signal intensity of DPPH? in a dose‐dependent manner over the range 0.1–2.5 mmol/L in the following order: NA > A > I > D, with IC50 = 0.30 ± 0.03 for noradrenaline and IC50 = 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5‐dimethyl‐1‐pyrroline N‐oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (kr) of CATs with HO? were found to be in the order of 109 L/mol/s, and the kr value for noradrenaline was the highest (kr = 8.4 × 109 L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62–73% at 1 mmol/L concentration and 79–89% at 2 mmol/L concentration) from a Fenton‐like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
952.
953.
Promoter variant-dependent mRNA expression of the MEF2A in longissimus dorsi muscle in cattle 总被引:1,自引:0,他引:1
The myocyte enhancer factor 2A (MEF2A) gene encodes a member of the myocyte enhancer factor 2 (MEF2) protein family that is involved in vertebrate skeletal, cardiac, and smooth muscle development and differentiation during myogenesis. According to recent studies, MEF2 genes might be major regulators of postnatal skeletal muscle growth; thus, they are considered to be important, novel candidates for muscle development and body growth in farm animals. The aim of the present study was to search for polymorphisms in the bovine MEF2A gene and analyze their effect on the MEF2A mRNA expression level in the longissimus dorsi muscle of Polish Holstein-Fresian cattle. In total, 4094?bp of the whole coding sequence and the promoter region of MEF2A were re-sequenced in 30 animals, resulting in the detection of 6 novel variants as well as one previously reported SNP. Three linked mutations in the promoter region (-780T/G, g.-768T/G, and g.-222A/G) and only two genotypes were identified in two Polish breeds (TTA/TTA and TTA/GGG). Three SNPs in the coding region [g.1599G/A (421aa), g.1626G/A (429aa), and g.1641G/A (434aa)] appeared to be silent substitutions and segregated as two intragene haplotypes: GGG and AAA. Expression analysis showed that the mutations in the promoter region are highly associated with the MEF2A mRNA level in the longissimus dorsi muscle of bulls carrying two different genotypes. The higher MEF2A mRNA level was estimated in the muscle of bulls carrying the TTA/TTA (p<0.01) genotype as compared with those with TTA/GGG. The results obtained suggest that the nucleotide sequence mutation in MEF2A might be useful marker for body growth traits in cattle. 相似文献
954.
Kułakowska A Mroczko B Mantur M Lelental N Tarasiuk J Kapica-Topczewska K Schulz U Lange P Zimmermann R Kornhuber J Lewczuk P 《Methods (San Diego, Calif.)》2012,56(4):528-531
Intrathecal synthesis of the antibodies specific to neurotrofic viruses: measles (M), rubella (R), Varicella-Zoster (Z), and/or H. simplex (H), known as "MRZH-reaction" plays important diagnostic role in multiple sclerosis (MS). Whereas the analysis of the oligoclonal IgG bands provides high sensitivity, the MRZH-reaction shows high specificity, and hence these methods complement each other. For the first time we applied multiplexing bead-based technology to simultaneously analyze cerebrospinal fluid (CSF) and serum concentrations of antibodies against these viruses, and to calculate the antibody specific indices (ASI's). The method shows reasonable precision: intra-assay, 2.9-6.7%, and inter-assay, 2.0-3.2%. The results are comparable with these obtained with other methods (ELISAs), including two runs of the certified external quality control schemes. Eighty-one percent of the MS cases (n=27) and none of the sex- and age-matched controls (n=14), except one subject with "borderline" anti-measles ASI of 1.5, showed intrathecal synthesis of IgG against at least one of the viruses discussed. The ratios of the MRZH-positive cases in the MS group were: 12/22 for M, 12/19 for R, 13/26 for Z, and 7/26 for H. We conclude that the multiplexing technology can be applied as a tool to study the intrathecal immune response in the diagnosis of MS. 相似文献
955.
Muehlbauer T Roth R Bopp M Granacher U 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(2):568-574
Compared with resistance training, information concerning the progressive configuration of balance training (BT) is rare and lacks scientific validation. Therefore, a study was designed to determine participants' ability to perform balance exercises with increasing level of difficulty. The task required the participants (N = 20) to stand as stable as possible on a computerized balance platform. The experiment was performed on 3 testing days using different stance and sensory conditions. On each day, bipedal, step, tandem, and monopedal stands were performed 3 times while sensory conditions changed from firm ground, eyes opened (day 1) over foam ground, eyes opened (day 2) to firm ground, eyes closed (day 3). The results showed that total center of pressure displacements significantly increased when the use of sensory information (comparison between testing days: all p < 0.001) or when the base of support (comparison within testing days: all p < 0.001) was gradually reduced. Based on the observed pattern of increased postural sway across all testing conditions and the levels of trial variability, exercises were categorized into several stages of training. Findings indicate that balance performance decreased in response to an increased level of task difficulty introduced by narrowing the base of support and by limiting the use of sensory information. Practitioners can use the derived exercise ranking to select exercises for BT appropriate to the level of participants' balance ability and to implement progression in balance training. 相似文献
956.
The morphological and functional heterogeneity of solid tumour cells can be observed in cancer cell lines cultured in vitro. We have combined analyses of microclones developed from single cells with micropore transmigration assays to demonstrate the co-existence of cellular subsets differing in morphology and motile activity, as well as Cx43 (connexin 43) and N-cadherin expression within lung carcinoma A549 populations. 'Fibroblastoid' cells, characterized by high motility, polarized morphology and plasmalemmal localization of Cx43, displayed the strongest aptitude for transmigration through narrow obstacles. Due to high mitotic activity, they maintain the whole population but can also give rise to a sub-population of quiescent and immobile 'epithelioid' cells. Our observations indicate that phenotypic transitions between the fibroblastoid and epithelioid phenotype account for the heterogeneity of metastable A549 cell populations. 相似文献
957.
Daniel Kubisz Łukasz Kajtoch Miłosz A. Mazur Agata Lis Milada Holecová 《Invertebrate Biology》2012,131(4):333-344
Xerothermic species are rare and threatened in central and eastern Europe. In light of the continuing loss of steppe‐like habitats due to anthropogenic fragmentation and degradation, the evaluation of genetic variation in populations inhabiting them is of immediate importance if appropriate conservation measures are to be undertaken. Here we report on the genetic diversity of the rare leaf beetle Crioceris quatuordecimpunctata, whose populations in central and eastern Europe inhabit highly geographically isolated areas. All of the studied populations (in Poland, Ukraine, and Slovakia) were differentiated at the mitochondrial marker COI. However, with respect to the nuclear marker ITS1, Polish populations were monomorphic, but distinct from all other populations. The distinctiveness of the studied populations was confirmed by Wolbachia screening, which showed that all populations carried different strains (one or two), which were probably transferred independently from other insects. On the other hand, no diversity was found in any marker within particular populations, which could be caused (at least for mtDNA) by a Wolbachia selective sweep. Crioceris quatuordecimpunctata probably consists of isolated populations, which went through narrow bottlenecks leading to a drastic reduction in their genetic diversity. As these populations are reciprocally monophyletic for mtDNA haplotypes and show a significant divergence of allele frequencies at nuclear loci, they could be classified as evolutionarily significant units (ESUs). In addition, DNA barcodes were used to identify Asparagus officinalis as the host plant for members of all studied populations. These data should be valuable in efforts to conserve populations of C. quatuordecimpunctata (e.g., for guiding reintroductions). 相似文献
958.
Raszeja-Wyszomirska J Safranow K Milkiewicz M Milkiewicz P Szynkowska A Stachowska E 《Prostaglandins & other lipid mediators》2012,99(1-2):51-56
Alcoholic liver disease (ALD) begins with the accumulation of lipid droplets in the liver. Lipids which accumulate in the liver can stimulate inflammation, and the fatty acid derivatives, hydroxyeicosatetraenoic acids (HETEs) and hydroxyoctadecadienoic acids (HODEs), may play an important role in this process. We evaluated the concentrations of linoleic and arachidonic acid derivatives in the plasma of patients with ALD, non-alcoholic fatty liver disease (NAFLD) and healthy individuals. The groups consisted of 173 subjects: 63 patients with ALD, 90 with NAFLD and 20 healthy volunteers. Plasma 12-, 15-, and 5-HETE as well as 9- and 13-HODE were assessed using HPLC and isoprostane 8-epi-PGF 2α III was evaluated with an ELISA. In addition the mRNA expression of lipoxygenases (5-LOX, 15-LOX-1, 15-LOX-2) in the liver samples of patients with ALD cirrhosis was measured. A significant difference between the plasma concentrations of the analyzed derivatives was found when divided according to gender. The most significant differences were found between healthy individuals and ALD patients, as well as ALD and NAFLD individuals regardless of gender. The increased plasma HODEs and HETEs concentrations were in line with the increase in 5- and 15-LOX-1 and 15-LOX-2 mRNA in liver samples from ALD cirrhosis patients. LOXs expression and peroxidation of polyunsaturated fatty acids by free radical-propagated chemical oxidation may be contributing factors in liver necroinflammatory injury in ALD. 相似文献
959.
Dworniczek E Piwowarczyk J Bania J Kowalska-Krochmal B Wałecka E Seniuk A Dolna I Gościniak G 《Acta microbiologica et immunologica Hungarica》2012,59(2):263-269
Enterococci, a complex group of facultative pathogens have become increasingly isolated in various hospital settings. They are considerable frequently cultured from traumatic and surgical wounds. We investigated 57 strains of the species E. faecalis, E. faecium and E. casseliflavus isolated from infected wounds. Their ability to produce virulence factors and their sensitivity to antibiotics were evaluated using phenotypic and genotyping methods. In the phenotype studies, significant portion of the isolates produced biofilm (66.7%) and gelatinase (36.8%). Nearly 30% of the strains expressed hemolytic properties. Only a few produced DNAse (15.8%) and lipase (7.0%). The genes esp, gelE, cylA, cylB, cylM and agg were detected in most of the isolates (38.6-87.7%). All the isolated enterococci were susceptible to vancomycin and were characterized by their low resistance to antibiotics, except aminoglycosides (HLR). 相似文献
960.