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31.
Cezary Skobowiat Grzegorz Panasiewicz Zygmunt Gizejewski Bozena Szafranska 《Tissue & cell》2013,45(6):402-406
Co-expression of dopamine β-hydroxylase (DβH) and neuropeptide Y (NPY) has never been examined in ovary (OV) and umbilical cord (UC) of the European bison (Eb), the endangered wild species. The OV and UC samples were harvested from seasonally eliminated Eb females (45–120 days post coitum). Frozen histological sections were examined by double fluorescent immunohistochemistry (dF-IHC), using the primary mouse anti-DβH monoclonals and rabbit anti-NPY polyclonals and then the immunocomplexes were visualized with FITC and CY3 fluorophores, respectively. Numerous DβH immunoreactive nerve fibers (DβH-IRs) and a little less frequent NPY-IRs were found in the bundle-like structures, innervating mainly perivascular regions of the OV. The NPY-IRs constantly co-expressed DβH, while some DβH-IRs did not express NPY. This specific pattern of innervation was observed both in the stromal and cortical regions of the OV. The simultaneous co-expression of DβH and NPY were also detected in the UC, in which specific single or bundle-like structures ran along the smooth muscles of blood vessels. The spatial-specific co-expression of DβH and NPY in OV and UC, may suggest that these markers are involved in the control of vascularization that regulates nourishing blood circulation required for proper pregnancy maintenance and efficient embryo/fetus development in the Eb. 相似文献
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The aim of the study was to test for diel patterns in the diet and habitat use in a feral, pond-dwelling, non-native fathead minnow Pimephales promelas population in England. Fish were collected in June 2009 using traps set in four habitat types (open waters, rushes??Juncus effusus, weeds??Potamogeton natans and mixed vegetation), then sexed and measured for total length and eviscerated weight in the laboratory. Data were analysed at 6-h intervals, with Fulton??s condition index and three dietary parameters (frequency of occurrence, number and weight) calculated. Minor diurnal differences in habitat use were observed in males, females and immatures, and these may be due to predator avoidance. Body condition varied greatly in rushes during daytime, probably due to shifts in habitat suitability (e.g. food, refuge). Detritus dominates the diet of native fathead minnow; however, planktonic crustaceans were the most important food resource for this population, with a clear ontogenetic shift, irrespective of habitat, towards greater proportion of ingested detritus in larger individuals. Overall, the results demonstrate that feral fathead minnows display substantial trophic plasticity and a wide range of habitat use, which is normally associated with invasive species. However, established fathead minnow populations in Europe are rare despite its wide-spread ornamental and scientific use. 相似文献
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Patrycja Rogala Grzegorz Czerwonka Sawomir Michakiewicz Maciej Hodorowicz Barbara Barszcz Agnieszka Jaboska‐Wawrzycka 《化学与生物多样性》2019,16(11)
The antibacterial and antibiofilm activities of two new ruthenium complexes against E. coli, S. aureus, P. aeruginosa PAO1 (laboratory strain) and P. aeruginosa LES B58 (clinical strain) were evaluated. Complexes, mer‐[RuIII(2‐bimc)3] ? H2O ( 1 ) and cis‐[RuIVCl2(2,3‐pydcH)2] ? 4H2O ( 2 ), were obtained using aromatic carboxylic acid ligands, namely, 1H‐benzimidazole‐2‐carboxylic acid (2‐bimcH) and pyridine‐2,3‐dicarboxylic acid (2,3‐pydcH2). Compounds were physicochemically characterized using X‐ray diffraction, Hirshfeld surface analysis, IR and UV/VIS spectroscopies, as well as magnetic and electrochemical measurements. Structural characterization revealed that Ru(III) and Ru(IV) ions in the complexes adopt a distorted octahedral geometry. The intermolecular classical and weak hydrogen bonds, and π???π contacts significantly contribute to structure stabilization, leading to the formation of a supramolecular assembly. Biological studies have shown that the Ru complexes inhibit the growth of bacteria and biofilm formation by the tested strains and the complexes seem to be a potential as antimicrobial agents. 相似文献
35.
Mateusz Meserszmit Grzegorz Swacha Lenka Pavl Vilm Pavl Adriana Trojanowska-Olichwer Zygmunt Kcki 《Global Change Biology Bioenergy》2022,14(1):54-64
Semi-natural lowland and mountain mesic meadows are grasslands rich in species, and their conservation status depends on treatments such as mowing or grazing livestock. In many countries, the condition of grasslands is deteriorating because of their inappropriate use or abandonment. This study aimed to determine the effects of the species composition of plant communities and functional plant groups on the methane yield from biomass harvested from mesic grasslands in the Sudetes Mountains. Biogas potential analysis was performed based on biomass samples collected from Poland and the Czech Republic. The biogas potential was determined in 40 day-long batch anaerobic digestion tests. The average methane yield obtained from the biomass was 246 ± 16 NL CH4 kg?1 VS, whereas the methane yield per hectare was 870 ± 203 m3 CH4 ha?1. Plant communities comprising different dominant species had no effect on the methane yield but affected the methane yield per hectare. Additionally, the species composition of grasslands with a higher percentage of forbs had lower biomass yield, resulting in lower methane yields per hectare. The continuity of the low-intensity management of mountain grassland, which can be provided by the utilization of their biomass for bioenergy production, sustains high biodiversity and ensures appropriate meadow conservation. 相似文献
36.
Mahieu F Owsianik G Verbert L Janssens A De Smedt H Nilius B Voets T 《The Journal of biological chemistry》2007,282(5):3325-3336
Menthol, a secondary alcohol produced by the peppermint herb, Mentha piperita, is widely used in the food and pharmaceutical industries as a cooling/soothing compound and odorant. It induces Ca2+ influx in a subset of sensory neurons from dorsal root and trigeminal ganglia, due to activation of TRPM8, a Ca2+-permeable, cold-activated member of the TRP superfamily of cation channels. Menthol also induces Ca2+ release from intracellular stores in several TRPM8-expressing cell types, which has led to the suggestion that TRPM8 can function as an intracellular Ca2+-release channel. Here we show that menthol induces Ca2+ release from intracellular stores in four widely used cell lines (HEK293, lymph node carcinoma of the prostate (LNCaP), Chinese hamster ovary (CHO), and COS), and provide several lines of evidence indicating that this release pathway is TRPM8-independent: 1) menthol-induced Ca2+ release was potentiated at higher temperatures, which contrasts to the cold activation of TRPM8; 2) overexpression of TRPM8 did not enhance the menthol-induced Ca2+) release; 3) menthol-induced Ca2+ release was mimicked by geraniol and linalool, which are structurally related to menthol, but not by the more potent TRPM8 agonists icilin or eucalyptol; and 4) TRPM8 expression in HEK293 cells was undetectable at the protein and mRNA levels. Moreover, using a novel TRPM8-specific antibody we demonstrate that both heterologously expressed TRPM8 (in HEK293 cells) and endogenous TRPM8 (in LNCaP cells) are mainly localized in the plasma membrane, which contrast to previous localization studies using commercial anti-TRPM8 antibodies. Finally, aequorin-based measurements demonstrate that the TRPM8-independent menthol-induced Ca2+ release originates from both endoplasmic reticulum and Golgi compartments. 相似文献
37.
Główka FK Łada MK Grund G Wachowiak J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):569-574
A direct and selective HPLC method with refractometric detection was worked out for determination of treosulfan in plasma and urine of children. Before injection onto reverse phase column plasma samples with treosulfan and barbital (I.S.) were clarified using filtration. The mobile phase was composed of phosphate buffer, pH 5 and acetonitrile. The linear range of the standard curve of treosulfan spanned concentrations of 10.0-2000.0 microg/ml and 50.0-10000.0 microg/ml in plasma and urine, respectively, and covered the levels found in biological fluids after infusion of the drug. The limit of detection amounted to 5 microg/ml for plasma and 25 microg/ml for urine. Intra- and inter-day precision and accuracy of the measurement fulfilled analytical criteria accepted in pharmacokinetic studies. Recovery of treosulfan as well as stability in biological fluids was also calculated. The validated method was successfully applied in pharmacokinetic studies of treosulfan administered to children prior to haematopoietic stem cell transplantation. Differences between pharmacokinetics of treosulfan in children and adults were also studied. 相似文献
38.
Potential relationship between glutathione metabolism and flocculation in the yeast Kluyveromyces lactis 总被引:1,自引:0,他引:1
Reduced glutathione (GSH) is involved in biochemical and physiological processes in cells. Flocculation is an important mechanism in microorganisms. The present study concerned the potential relationship between GSH metabolism and flocculation. Two yeast strains, a flocculent (Kluyveromyces lactis 5c) and a nonflocculent (Kluyveromyces lactis 5a) strain, were used. The level of intracellular GSH measured during the growth period was significantly higher in the nonflocculent than in the flocculent strain; in contrast, the flocculent strain exhibited brighter staining of vacuoles than the nonflocculent strain when observed using epifluorescence microscopy. Compounds acting either on flocculation (EDTA, galactose) or on GSH metabolism (buthionine sulfoximine, and N-acetylcysteine) were tested on the flocculent strain during the growth period. Both EDTA and galactose fully inhibited flocculation and induced GSH overproduction of 58% and 153%, respectively. Buthionine sulfoximine decreased GSH level by 76% but had no effect on flocculation; N-acetylcysteine increased the GSH level and flocculation by 106% and 41%, respectively. Combination of EDTA and N-acetylcysteine produced similar effects than with each of them. Combination of galactose and N-acetylcysteine increased the GSH level but decreased flocculation. These results demonstrated that GSH homeostasis is linked to the flocculation mechanism. A hypothesis related to stress is given. 相似文献
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