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991.
Characterization of gibberellin-signalling elements during plum fruit ontogeny defines the essentiality of gibberellin in fruit development 总被引:2,自引:0,他引:2
992.
993.
Osteoprotective effect of soybean and sesame oils in ovariectomized rats via estrogen-like mechanism
The purpose of the present study was to investigate the osteoprotective effects of soybean oil (SbO) and sesame oil (SO) in ovarictomized (OVX) rats. The results indicated that the OVX rats exhibited a significant decrease in Ca and P level in both serum and bone, the activities of the antioxidant enzymes SOD and CAT and the antioxidant biomarker GSH accompanied with a marked increase in the oxidative stress markers MDA and PC, the inflammatory indices (TNF-α, CRP levels, WBCs counts and ACP activity) in, both, bone and serum. Supplementating the diet of the OVX rats with SbO (15 % w/w) or SO (10 % w/w) for 2 months to resulted in modulation of the alterations in all tested parameters and succeeded to restore minerals, antioxidant enzymes, antioxidant biomarkers, oxidative stress markers, inflammatory indices, and WBCs counts. It could be concluded that the consumption of diets supplemented with SbO or SO might be useful for preventing bone loss caused by estrogen deficiency in ovariectomy status. 相似文献
994.
Beata Grzywacz Klaus‐Gerhard Heller Arne W. Lehmann Elbieta Warchaowska‐
liwa Gerlind U. C. Lehmann 《Journal of Zoological Systematics and Evolutionary Research》2014,52(2):109-118
We used molecular characters to infer the phylogenetic position of the Western Mediterranean bushcricket genus Odontura and to trace its high karyotype diversity. Analysis of 1391 base pairs of two mitochondrial genes (COI and ND1) and one nuclear sequence (ITS2) was conducted. Phylogenetic topologies were estimated using maximum parsimony, maximum likelihood and likelihood‐based Bayesian inference. The genus Odontura is a phylogenetic outlier in respect of all other European Phaneropterinae genera and has been proposed to have originated from a hitherto unknown ancestor. Our results support the monophyly of the genus Odontura and the recognition of two subgenera: Odontura and Odonturella. We found that both Sicilian taxa of the subgenus Odontura have a completely identical morphology and song patterns. Combining these results, we proposed that both should be treated as subspecies: O. (Odontura) stenoxypha stenoxypha and O. (O.) st. arcuata. Bioacoustic data also proved to support independent markers, with song characteristics reflecting the molecular topology. Mapping the karyotypic characters onto the phylogenetic tree allows a reconstruction of the directions and transitional stages of chromosome differentiation. The number of autosomes within the genus Odontura ranges from 26 to 30. In addition to the ancestral X0 sex determination mechanism, neo‐XY and neo‐X1X2Y sex chromosomes have evolved independently. 相似文献
995.
Rita Vilaça Elísio Silva André Nadais Vítor Teixeira Nabil Matmati Joana Gaifem Yusuf A. Hannun Maria Clara Sá Miranda Vítor Costa 《Molecular microbiology》2014,91(3):438-451
The Niemann‐Pick type C is a rare metabolic disease with a severe neurodegenerative phenotype characterized by an accumulation of high amounts of lipids (cholesterol and sphingolipids) in the late endosomal/lysosomal network. It is caused by loss‐of‐function point mutations in either NPC1 or NPC2, which seem to mediate proper intracellular lipid transport through endocytic pathway. In this study, we show that yeast cells lacking Ncr1p, an orthologue of mammalian NPC1, exhibited a higher sensitivity to hydrogen peroxide and a shortened chronological lifespan. These phenotypes were associated with increased levels of oxidative stress markers, decreased levels of antioxidant defences and mitochondrial dysfunctions. Moreover, we report that Ncr1p‐deficient cells displayed high levels of long chain bases (LCB), and that Sch9p‐phospho‐T570 and Sch9p levels increased in ncr1Δ cells through a mechanism regulated by Pkh1p, a LCB‐activated protein kinase. Notably, deletion of PKH1 or SCH9 suppressed ncr1Δ phenotypes but downregulation of de novo sphingolipid biosynthesis had no protective effect, suggesting that LCBs accumulation may result from an increased turnover of complex sphingolipids. These results suggest that sphingolipid signalling through Pkh1p‐Sch9p mediate mitochondrial dysfunction, oxidative stress sensitivity and shortened chronological lifespan in the yeast model of Niemann‐Pick type C disease. 相似文献
996.
Paweł Łaniewski Maciej Kuczkowski Klaudia Chrząstek Anna Woźniak Agnieszka Wyszyńska Alina Wieliczko Elżbieta Katarzyna Jagusztyn-Krynicka 《World journal of microbiology & biotechnology》2014,30(1):281-292
Campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by Campylobacter is considered to be one of the most frequent sources of human infection in developed countries. Here we evaluated the immunogenicity and protective efficacy of Salmonella Typhimurium χ9718 producing the Campylobacter jejuni CjaA protein as a chicken anti-Campylobacter vaccine. In this study chickens were orally immunized with a new generation S. Typhimurium strain χ9718 with regulated delayed attenuation in vivo and displaying delayed antigen expression. The immunization with the S. Typhimurium χ9718 strain producing C. jejuni CjaA antigen induced strong immune responses against CjaA in both serum IgY and intestinal IgA, however, it did not result in the significant reduction of intestinal colonization by Campylobacter strain. The low level of protection might arise due to a lack of T cell response. Our results demonstrated that a Salmonella strain with regulated delayed attenuation and displaying regulated delayed antigen expression might be an efficient vector to induce immune response against Campylobacter. It seems that an efficient anti-Campylobacter subunit vaccine should be multicomponent. Since S. Typhimurium χ9718 contains two compatible balanced-lethal plasmids, it can provide the opportunity of cloning several Campylobacter genes encoding immunodominant proteins. It may also be used as a delivery vector of eukaryotic genes encoding immunostimulatory molecules to enhance or modulate functioning of chicken immune system. 相似文献
997.
Gregory M. Crutsinger Seth M. Rudman Mariano A. Rodriguez‐Cabal Athena D. McKown Takuya Sato Andrew M. MacDonald Julian Heavyside Armando Geraldes Edmund M. Hart Carri J. LeRoy Rana W. El‐Sabaawi 《Molecular ecology》2014,23(23):5888-5903
A ‘genes‐to‐ecosystems’ approach has been proposed as a novel avenue for integrating the consequences of intraspecific genetic variation with the underlying genetic architecture of a species to shed light on the relationships among hierarchies of ecological organization (genes → individuals → communities → ecosystems). However, attempts to identify genes with major effect on the structure of communities and/or ecosystem processes have been limited and a comprehensive test of this approach has yet to emerge. Here, we present an interdisciplinary field study that integrated a common garden containing different genotypes of a dominant, riparian tree, Populus trichocarpa, and aquatic mesocosms to determine how intraspecific variation in leaf litter alters both terrestrial and aquatic communities and ecosystem functioning. Moreover, we incorporate data from extensive trait screening and genome‐wide association studies estimating the heritability and genes associated with litter characteristics. We found that tree genotypes varied considerably in the quality and production of leaf litter, which contributed to variation in phytoplankton abundances, as well as nutrient dynamics and light availability in aquatic mesocosms. These ‘after‐life’ effects of litter from different genotypes were comparable to the responses of terrestrial communities associated with the living foliage. We found that multiple litter traits corresponding with aquatic community and ecosystem responses differed in their heritability. Moreover, the underlying genetic architecture of these traits was complex, and many genes contributed only a small proportion to phenotypic variation. Our results provide further evidence that genetic variation is a key component of aquatic–terrestrial linkages, but challenge the ability to predict community or ecosystem responses based on the actions of one or a few genes. 相似文献
998.
Katarzyna Oszajca Konrad Wroński Grażyna Janiszewska Małgorzata Bieńkiewicz Jacek Bartkowiak Janusz Szemraj 《Molecular biology reports》2014,41(5):2859-2864
The most important feature of abdominal aortic aneurysm (AAA) pathogenesis is an enzymatic degradation of elastic lamellae and extracellular matrix proteins particularly with participation of matrix metalloproteinases. Plasmin, which is responsible for the dissolution of fibrin in blood vessels, plays also a key role in the cascade for activation of the metalloproteinases. The purpose of this study was to evaluate the influence of selected polymorphisms in genes coding for tissue plasminogen activator (?7351 C/T polymorphism), urokinase-type plasminogen activator (1788 C/T polymorphism) and plasminogen activator inhibitor 1 (?675 4G/5G and ?844 G/A polymorphism) on the susceptibility to AAA. We performed a case–control study of 153 polish patients hospitalized due to AAA and compared them with matched healthy control subjects. The polymorphisms were ascertained through genotyping by polymerase chain reaction and restriction digestion of amplified fragments or through high-resolution melting analysis. In this study we have found lower frequency of wild-type GG genotype of the ?844G/A PAI-1 polymorphism in cases than in controls, what may suggest the protective effect of this genotype for the risk of AAA development. None of the remaining polymorphisms tested were associated with AAA occurrence. 相似文献
999.
Micha? Mi?tus El?bieta Nowak Marcin Jaciuk Pawe? Kustosz Justyna Studnicka Marcin Nowotny 《Nucleic acids research》2014,42(16):10762-10775
Rad2/XPG belongs to the flap nuclease family and is responsible for a key step of the eukaryotic nucleotide excision DNA repair (NER) pathway. To elucidate the mechanism of DNA binding by Rad2/XPG, we solved crystal structures of the catalytic core of Rad2 in complex with a substrate. Rad2 utilizes three structural modules for recognition of the double-stranded portion of DNA substrate, particularly a Rad2-specific α-helix for binding the cleaved strand. The protein does not specifically recognize the single-stranded portion of the nucleic acid. Our data suggest that in contrast to related enzymes (FEN1 and EXO1), the Rad2 active site may be more accessible, which would create an exit route for substrates without a free 5′ end. 相似文献
1000.
Cyclooxygenase-2 (COX-2) is overexpressed in hepatocellular carcinoma (HCC) and considered to play a role in hepatic carcinogenesis. Our aim was to examine the associations between polymorphisms in COX-2 − 765G→C and − 1195A→G and risk of HCC. We conducted a case–control study including 120 patients with HCC and 130 age- and gender-matched controls. Genotypes of the COX-2 polymorphisms − 765G→C and − 1195A→G were determined by polymerase chain reaction-based restriction fragment length polymorphism. No significant difference was observed in the genotype distribution of the − 765G→C polymorphism between patients and controls. The − 1195AA genotype was associated with an increased risk of developing HCC (OR, 2.5; 95%CI, 1.18–5.37). The A allele was present significantly more often in HCC patients (OR 1.5; 95%CI, 1.05–2.14). In conclusion, our results demonstrated that the − 1195AA genotype and A allele have an important role in HCC risk in Egyptian patients. 相似文献