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Continuous cropping of cotton causes accumulation of allelochemicals in soil that results in substantial crop yield and quality losses. To elucidate the physiological mechanism of the effects of allelochemicals on cotton root growth, and solve the problem of continuous cropping obstacles, hydroponics experiments were carried out to study the effects of three allelochemicals (p-hydroxybenzoic acid (PHBA), phloroglucinol, and ferulic acid) at different concentrations (0.8, 4.0, and 20.0 mmol L⁻¹) on the production of reactive oxygen species, antioxidant enzyme activities, and mitochondrial function of cotton seedling roots. All three phenolic compounds suppressed cotton root growth, decreased the activity of antioxidant enzymes (superoxide dismutase, catalase and peroxidase) and H⁺-ATPase in root mitochondria, and increased generation of O₂⁻ and the content of H₂O₂. They also increased the degree of openness of mitochondria permeability transition pores, and decreased the membrane fluidity of mitochondria, and the ratio of cytochrome (Cyt) c/a, thus resulting in the damage of mitochondrial structure and overall function of the root system. Ferulic acid at 20.0 mmol L⁻¹ inhibited cotton root growth more than the other treatments. Above all, all three kinds of allelochemicals inhibited antioxidant enzyme activity and mitochondrial function in cotton seedling roots, and the inhibition depended on the dose of phenolic compounds. Compared to PHBA and phloroglucinol, ferulic acid was a stronger inhibitor of cotton seedling root growth.
A protease with a molecular mass of 30 kDa and the N-terminal sequence of GLQTNAPWGLARSS, was isolated from fresh fruiting bodies of the wild edible mushroom Termitomyces albuminosus. The purification protocol included ion exchange chromatography on DEAE-cellulose, Q-Sepharose, SP-Sepharose and FPLC-gel filtration on Superdex 75. The protein was unadsorbed on DEAE-cellulose and Q-Sepharose, but adsorbed on SP-Sepharose. The optimal pH and temperature of the purified enzyme were 10.6 and 60°C, respectively. The enzyme was stable in the presence of 2% (v/v) Tween 80 and 4 M urea. More than 80% of the enzyme activity was retained in 2% (v/v) Triton X 100, 54% in 10 mM EDTA and 31% in 2% (w/v) SDS. The enzyme was strongly inhibited by phenylmethylsulfonyl fluoride (PMSF), but not inhibited by dithiothreitol (DTT), pepstatin or lima bean trypsin inhibitor suggesting that it was a serine protease but not a trypsin-like one. The protease was inhibited by Hg2+, Cu2+, and Fe3+ ions. The Km and Vmax values of the purified enzyme for casein were 8.26 mg∙ml−1 and 0.668 mg∙ml−1∙min−1, respectively.
Background: Patients with anti-β2GPI antibodies display significantly higher platelet activation/aggregation and vascular endothelial cell damage. The mechanism underlying the correlation between platelet activation, vascular endothelial cell dysfunctions and anti-β2GPI antibodies remains unknown. Methods: In this study, we derived miR-96 and -26a from platelets activated by the antiβ2GPI/β2GPI complex and explored their role in modulating human umbilical vein endothelial cell (HUVEC) migration and tube formation. Results: Anti-β2GPI/β2GPI complex induces the release of platelet-derived microparticles (p-MPs). The amounts of miR-96 and -26a in these p-MPs were also higher than for the control group. Co-incubation of HUVECs with p-MPs resulted in the transfer of miR96 and -26a into HUVECs, where they inhibited migration and tube formation. The targeting role of these miRNAs was further validated by directly downregulating targeted selectin-P (SELP) and platelet-derived growth factor receptor alpha (PDGFRA) via luciferase activity assay. Conclusion: Our study suggests that miR-96 and -26a in p-MPs can inhibit HUVEC behavior by targeting SELP and PDGFRA.
As a common plant in Momoge Wetland, Scirpus planiculmis is the major food source for Siberian Crane (Grus leucogeranus), which is one of the most valuable waterfowl in Momoge Wetland. Through a simulation experiment, this study investigated the effects of different water table depths (-5, 5, 10, 20, and 30 cm) and salinities (300, 1,000, 3,000, 4,000, and 5,000 mg/L) on the eco-physiological characteristics (height, leaf area per plant, chlorophyll content, and chlorophyll fluorescence) of Scirpus planiculmis. The results indicate that for the seedlings of Scirpus planiculmis, the effects of water depth on plant height, leaf area per plant, and chlorophyll content were significant, while salinity affected height increment, chlorophyll content, and chlorophyll fluorescence parameters. For the plants of Scirpus planiculmis, the water depth had a significant effect on height increment and chlorophyll content, while salinity had a significant effect on height increment, chlorophyll content, and chlorophyll fluorescence parameters. These results indicate a suitable ecological response thresholds of water table and salinity on the growth of Scirpus planiculmis seedlings and plants, which were 5-10 cm and less than 3,000 mg/L for seedlings, 30 cm and 300-4,000 mg/L for plants.
The experiment was conducted to investigate the formation of oxidative stress and the development of anti-oxidative enzymes in two barley genotypes differing in anoxia tolerance. Waterlogging led to significant reduction in root and shoot weight, green leaf area and tillers per plant, but tolerant Xiumai 3 was much less reduced than sensitive Gerdner. Malondialdehyde (MDA) content, an indicator of membrane lipid peroxidation, significantly increased in Gerdner when the plants were subjected to waterlogging, but remained little changed in Xiumai 3. Superoxide dismutase (SOD) activity was increased with waterlogging treatment and the sensitive cultivar had higher activity than the tolerant one during the experimental duration. At early stage of waterlogging treatment, both peroxidase (POD) and catalase (CAT) activities significantly increased in Xuimai 3, while obviously decreased in Gerdner. Moreover, both cultivars showed substantial increase in both POD and CAT with the progress of waterlogging exposure. Glutathione reductase (GR) activity was increased in both tolerant- and sensitive cultivars under waterlogging. It may be assumed from the current results that SOD activity appears to be not a constraining factor limiting the scavenging of ROS, and it is the change of POD and CAT activity under waterlogging that determine the status of oxidative stress. The difference between genotypes in waterlogging tolerance could be distinguished from the changed patterns of these enzymatic activities.
The concentrations of different phosphorus (P) species and four kinds of bioavailable P (algae-available P, AAP; Olsen P, OLP; water-soluble P, WSP; and readily desorbable P, RDP) were determined to investigate the relationship between phosphorus bioavailability and phosphorus speciation in sediments from rural rivers in Taihu Lake area, China, using a European Commission “Standards Measurements and Testing Program” protocol and four chemical extraction techniques. The total P and inorganic P concentrations in the sediments were 179-2,293 mg/kg and 137-1,857 mg/kg, respectively. The concentrations of the P species in the sediments followed the order NaOH- extractable P > HCl-extractable P > organic P. The bioavailable P concentrations followed the order AAP (340 mg/kg) > OLP (38.7 mg/kg) > WSP (1.8 mg/kg) > RDP (0.3 mg/kg). Regression analyses showed that there were good correlations between the P species concentrations and the bioavailable P concentrations measured using the four different methods, except for between WSP and the HCl-extractable P concentrations. The OLP concentrations had highly significant correlations with AAP, WSP, RDP and the P species concentrations. The OLP method was found to be most suitable for determining the bioavailability of P species under the prevalent geochemical conditions in the rural river sediments that were analyzed.
Genus Lithoaphis Takahashi, 1959 is reported from China. One new species Lithoaphis quercisucta sp. nov. from Yunnan Province, China is described. Diagnosis character, key of species, distribution, host plant and biology of the genus Lithoaphis are provided. Morphological description, feature pictures, distribution, and host plant of the new species are included in this paper. All specimens including the type are deposited in the Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, P. R. China.
The aphid subgenus, Tuberolachnus (Tuberolachniella) Hille Ris Lambers et Basu, 1966 is newly recorded from China. A new species, Tuberolachnus (Tuberolachniella) macrotuberculatus sp. nov. is described. The types are deposited in Zoological Museum, Institute of Zoology, Chinese Academy of Sciences.
Difference in isozymes and activities of peroxidase (POD) and superoxide dismutase (SOD) in two barley (Hordeum vulgare L.) genotypes differing in salt tolerance (Gebeina, tolerant; Quzhou, sensitive) was investigated using a hydroponic experiment. The activities of both enzymes were significantly increased when the plants of the two barley genotypes were exposed to salt stress, with salt-tolerant genotype being generally higher than the sensitive one. The variation in the POD and SOD isozymes was dependent on barley genotype, salt level and exposure time. When the plants were exposed to salt stress for 10 days, two new POD isozymes were found, Rm0.26 (Rm, relative mobility of enzyme to dye) in Gebeina and Rm0.45 in Quzhou. Both isozymes disappeared after 20 days of salt stress, but Rm0.26 appeared again 30 days after the stress. Two new SOD isozymes of Rm0.19 and Rm0.46 were found in Gebeina when exposed to NaCl for 10 days, but only Rm0.46 in Quzhou. As the time of salt stress extended, more new SOD isozymes were detected, Rm0.35 in both genotypes in all different salt treatments and Rm0.48 in Gebeina under 200 mM NaCl stress. At 30 days after the stress, all the new SOD isozymes disappeared except for Rm0.48 in Gebeina under 200 mM NaCl stress. The results suggest that the increased POD and SOD activities could be partly due to the formation of some new isozymes and the tolerant variety had better ability to form new isozymes to overcome salt stress.
Thie study aimed at comparing polymorphisms in exons of the IGFBP-1 gene encoding insulinlike growth factor binding protein-1 among three chicken breeds and analysing the associations between its genotypes and body weight traits in the Jinghai Yellow chicken. Three mutations (A2276T, T2359C and T5550C) and one insertion/deletion (the inserted/deleted AAT after position 5692bp) were detected in three chicken breeds. The general linear model analysis showed that the Jinghai Yellow chickens with BB and AB genotypes at the position 2276 (A2276T transversion) had significantly higher body weight than those of AA genotype (P<0.05 or P<0.01) at week 4, 8, and 16 of age. Moreover, BB genotype had significantly higher body weight at week 12 of age than those of AB genotype (P<0.01). The B allele had a positive effect on body weight traits.
Background: Mishandling of intracellular chloride (Cl−) concentration ([Cl−]i) in cerebrovascular smooth muscle cells is implicated in several pathological processes, including hyperplasia and remodeling. We investigated the effects of ClC-2-mediated Cl− efflux on the proliferation of human brain vascular smooth muscle cells (HBVSMCs) induced by angiotensin II (AngII). Methods: Cell proliferation and motility were determined using the CCK-8, bromodeoxyuridine staining, wound healing and invasion assays. ClC-2, PCNA, Ki67, survivin and cyclin D1 expression, and β-catenin and GSK-3β phosphorylation were examined using western blotting. Histological analyses were performed using hematoxylin and eosin staining and α-SMA staining. Results: Our results showed that AngII-induced HBVSMC proliferation was accompanied by a decrease in [Cl− ]i and an increase in ClC-2 expression. Inhibition of ClC-2 by siRNA prevented AngII from inducing the efflux of Cl− . AngII-induced HBVSMC proliferation, migration and invasion were significantly attenuated by ClC-2 downregulation. The inhibitory effects of ClC-2 knockout on HBVSMC proliferation and motility were associated with inactivation of the Wnt/β-catenin signaling pathway, as evidenced by inhibition of β-catenin phosphorylation and nuclear translocation, and decrease of GSK-3β phosphorylation and survivin and cyclin D1 expression. Recombinant Wnt3a treatment markedly reversed the effect of ClC-2 knockdown on HBVSMC viability. An in vivo study revealed that knockdown of ClC-2 with shRNA adenovirus ameliorated basilar artery remodeling by inhibiting Wnt/β-catenin signaling in AngII-treated mice. Conclusion: This study demonstrates that blocking ClC-2-mediated Cl− efflux inhibits AngII-induced cerebrovascular smooth muscle cell proliferation and migration by inhibiting the Wnt/β-catenin pathway. Our data indicate that downregulation of ClC-2 may be a viable strategy in the prevention of hyperplasia and remodeling of cerebrovascular smooth muscle cells.
 A novel antibacterial protein with a molecular mass of 44 kDa has been isolated from dried fruiting bodies of the wild mushroom Clitocybe sinopica. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis showed that the protein was composed of two subunits each with a molecular mass of 22 kDa. Its N-terminal amino-acid sequence, SVQATVNGDKML, has not been reported for other antimicrobial proteins. The purification protocol included ion exchange chromatography on DEAE-cellulose, CM-cellulose and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The antibacterial protein was adsorbed on all three ion exchangers. The antimicrobial activity profile of the protein against tested bacterial and fungal strains disclosed that it possessed potent antibacterial activity against Agrobacterium rhizogenes, A. tumefaciens, A. vitis, Xanthomonas oryzae and X. malvacearum with a minimum inhibitory concentration mostly below 0.6 μM. However, it had no antibacterial activity against Pseudomonas batatae, Erwinia herbicola, Escherichia coli, and Staphylococcus aureus, and no antifungal activity against Setosphaeria turcica, Fusarium oxysporum, Verticillium dahliae, Bipolaris maydis, and B. sativum. The antibacterial antivity against A. tumefaciens was stable after exposure to 20-60°C for 30 min and to pH 4-9 for 1 h.
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