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71.
72.
Tadaiti Ozato Júnior José Osmar Gaspar Priscila Belintani 《Journal of Phytopathology》2009,157(9):573-575
The sequence of the central part (ORF2) of a Brazilian isolate of Southern bean mosaic virus (SBMVSP ) is described. This ORF is 2888 nt long and together with the previously-sequenced 5' and 3' ends provides the complete nucleotide sequence of this virus isolate. The SBMVSP RNA encodes four overlapping open reading frames (ORF1, ORF2a, ORF2b, ORF4) and has a genome organization similar to that of the Cocksfoot mottle sobemovirus . 相似文献
73.
Votto AP Domingues BS de Souza MM da Silva Júnior FM Caldas SS Filgueira DM Clementin RM Primel EG Vallochi AL Furlong EB Trindade GS 《Biological research》2010,43(4):429-437
Onion (Allium cepa) is being studied as a potential anticancer agent, but little is known regarding its effect in multidrug resistance (MDR) cells. In this work, the cytotoxicity of crude onion extract (OE) and fractioned extract (aqueous, methanolic and ethyl acetate), as well as some onion compounds (quercetin and propyl disulfide) were evaluated in Lucena MDR human erythroleukemic and its K562 parental cell line. The capacity of OE to induce apoptosis and/or necrosis in these cells, the possible participation of oxidative stress and DNA damage were also assessed. Similar sensitivities were obtained for both tumoral cells, however only OE caused significant effects in the cells. In K562 cells, a significant increase of apoptosis was verified while the Lucena cells experienced a significant increase of necrosis. An antioxidant capacity was verified for OE discarding oxidative damage. However, OE provoked similar significant DNA damage in both cell lines. Thus, the OE capacity to overcome the MDR phenotype suggests anti-MDR action of OE. 相似文献
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75.
Moraes TB Ferreira JL da Rosa CE Sandrini JZ Votto AP Trindade GS Geracitano LA Abreu PC Monserrat JM 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2006,142(3-4):293-300
Polychaeta species like Laeonereis acuta (Nereididae) usually secrete great amounts of mucus that wrap the animal inside. Taking into account that fungi action in the sediment and UV radiation acting on dissolved organic matter in the water produces reactive oxygen species (ROS) like hydrogen peroxide (H(2)O(2)), it was considered that the mucus secretion could represent an antioxidant defense against environmental ROS. Antioxidant enzymes (catalase-CAT; superoxide dismutase-SOD; glutathione peroxidase-GPx and glutathione-S-transferase-GST) and total antioxidant capacity (TOSC) were determined in worms and mucus secretion. Higher (p<0.05) CAT, GPx and TOSC values were registered in mucus samples respect worms, SOD activity was similar (p>0.05) in both kind of samples, and absence of GST activity was observed in mucus samples, suggesting absence of catalyzed phase II reactions. In assays conducted with hepatoma cell lines exposed to H(2)O(2), it was verified that: (1) mucus co-exposure significantly (p<0.05) lowered DNA damage induced by H(2)O(2); (2) ROS production was significantly (p<0.05) reduced when cells were exposed simultaneously with mucus samples and H(2)O(2) respect H(2)O(2) alone. It can be concluded that the mucus production contributes substantially to the antioxidant defense system of the worm against environmental ROS through the interception or degradation of H(2)O(2), peroxyl and hydroxyl radicals. 相似文献
76.
Rocha Taina Teixeira Araújo Diene Xavier de Carvalho Alexandre Alves Germano Carolina Mesquita de Fátima Santos Maria Lameira Osmar Alves Bertolucci Suzan Kelly Vilela Pinto José Eduardo Brasil Pereira 《In vitro cellular & developmental biology. Plant》2022,58(4):636-652
In Vitro Cellular & Developmental Biology - Plant - Plants of the Verbenaceae family are well known for having constituents with important bioactive properties. The objective of this study was... 相似文献
77.
da Silveira Marina Bonfogo Pansa Camila Cristiane Malaspina Osmar Moraes Karen C. M. 《Molecular biology reports》2021,48(4):3463-3474
Molecular Biology Reports - Hepatocellular carcinoma is one of the most common types of cancer in the world with high mortality rate and new therapies that control of fatty acid metabolism may... 相似文献
78.
John Clifton-Brown Astley Hastings Moritz von Cossel Donal Murphy-Bokern Jon McCalmont Jeanette Whitaker Efi Alexopoulou Stefano Amaducci Larisa Andronic Christopher Ashman Danny Awty-Carroll Rakesh Bhatia Lutz Breuer Salvatore Cosentino William Cracroft-Eley Iain Donnison Berien Elbersen Andrea Ferrarini Judith Ford Jörg Greef Julie Ingram Iris Lewandowski Elena Magenau Michal Mos Martin Petrick Marta Pogrzeba Paul Robson Rebecca L. Rowe Anatolii Sandu Kai-Uwe Schwarz Danilo Scordia Jonathan Scurlock Anita Shepherd Judith Thornton Luisa M. Trindade Sylvia Vetter Moritz Wagner Pei-Chen Wu Toshihiko Yamada Andreas Kiesel 《Global Change Biology Bioenergy》2023,15(5):538-558
Demand for sustainably produced biomass is expected to increase with the need to provide renewable commodities, improve resource security and reduce greenhouse gas emissions in line with COP26 commitments. Studies have demonstrated additional environmental benefits of using perennial biomass crops (PBCs), when produced appropriately, as a feedstock for the growing bioeconomy, including utilisation for bioenergy (with or without carbon capture and storage). PBCs can potentially contribute to Common Agricultural Policy (CAP) (2023–27) objectives provided they are carefully integrated into farming systems and landscapes. Despite significant research and development (R&D) investment over decades in herbaceous and coppiced woody PBCs, deployment has largely stagnated due to social, economic and policy uncertainties. This paper identifies the challenges in creating policies that are acceptable to all actors. Development will need to be informed by measurement, reporting and verification (MRV) of greenhouse gas emissions reductions and other environmental, economic and social metrics. It discusses interlinked issues that must be considered in the expansion of PBC production: (i) available land; (ii) yield potential; (iii) integration into farming systems; (iv) R&D requirements; (v) utilisation options; and (vi) market systems and the socio-economic environment. It makes policy recommendations that would enable greater PBC deployment: (1) incentivise farmers and land managers through specific policy measures, including carbon pricing, to allocate their less productive and less profitable land for uses which deliver demonstrable greenhouse gas reductions; (2) enable greenhouse gas mitigation markets to develop and offer secure contracts for commercial developers of verifiable low-carbon bioenergy and bioproducts; (3) support innovation in biomass utilisation value chains; and (4) continue long-term, strategic R&D and education for positive environmental, economic and social sustainability impacts. 相似文献
79.
The quorum-sensing interfering RNAIII-inhibiting peptide (RIP) YSPXTNF and its synthetic analogues YSPWTNF and YSPITNF have been shown to prevent and suppress diseases caused by Staphylococcus aureus at different body sites in different animal models. This study was designed to investigate histopathologically the therapeutic efficacy of lead peptide RIP YSPWTNF-NH(2) in the subcutaneous air sac murine model of acquired S. aureus sepsis. Two experimental protocols were evaluated: an infection/therapy protocol, for which twenty BALB/c mice per group were infected with a subcutaneous inoculum of S. aureus strain ATCC 25923 ( [Formula: see text] colony forming units) that were either pretreated or not with 150microg of peptide RIP, and a safety protocol, for which three uninfected mice per group received treatment with either 150microg of peptide RIP or saline. Therapeutic efficacy was assessed by clinical examination for a period of 20 days and histopathology at 12, 24, 36, 48, 96 and 168h after inoculation. Treatment safety was assessed histopathologically at 24, 48 and 264h after inoculation. Subcutaneous administration of uninfected control mice with a single dose of peptide RIP YSPWTNF caused no significant histopathology in most organs examined, except for slight to moderate lung and liver congestions. In contrast to the situation with the untreated infected control group mice that presented with histopathological alterations consistent with the diagnosis of rapidly progressive and highly erosive disease (100% mortality by day 3), treatment of infected animals with peptide RIP YSPWTNF had a profound therapeutic effect on survival rate (67% by day 20) and on disease progression. The histopathological examination confirmed the clinical findings showing that extensive tissue damage at the site of the infection and in organs were greatly suppressed in the peptide RIP-treated animals. 相似文献
80.
Regulation of nitric oxide and bcl-2 expression by shear stress in human osteoarthritic chondrocytes in vitro 总被引:3,自引:0,他引:3
Lee MS Trindade MC Ikenoue T Goodman SB Schurman DJ Smith RL 《Journal of cellular biochemistry》2003,90(1):80-86
Onset and progression of cartilage degeneration is associated with shear stress occurring in diarthrodial joints subjected to inappropriate loading. This study tested the hypothesis that shear stress induced nitric oxide is associated with altered expression of regulatory onco-proteins, bcl-2, and Fas (APO-1/CD95) and apoptosis in primary human osteoarthritic chondrocyte cultures. Shear stress induced membrane phosphatidylserine and nucleosomal degradation were taken as evidence of chondrocyte apoptosis. Application of shear stress upregulated nitric oxide in a dose-dependent manner and was associated with increases in membrane phosphatidylserine and nucleosomal degradation. Increasing levels of shear stress decreased expression of the anti-apoptotic factor, bcl-2, from 44 to 10 U/ml. Addition of the nitric oxide antagonists, L-N(5)-(1-iminoethyl) ornithine and Nomega-nitro-L-arginine methyl ester (L-NAME), reduced shear stress induced nucleosomal degradation by 62% and 74%, respectively. Inhibition of shear stress induced nitric oxide release by L-NAME coincided with a 2.7-fold increase of bcl-2, when compared to chondrocytes exposed to shear stress in the absence of L-NAME. These data suggest that shear stress induced nitric oxide is associated with changes in apoptotic regulatory factors that alter chondrocyte metabolism and may contribute to joint degeneration. 相似文献