321 research outputs found

    Functional analysis of the theobroma cacao NPR1 gene in arabidopsis

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    <p>Abstract</p> <p>Background</p> <p>The <it>Arabidopsis thaliana NPR1 </it>gene encodes a transcription coactivator (NPR1) that plays a major role in the mechanisms regulating plant defense response. After pathogen infection and in response to salicylic acid (SA) accumulation, NPR1 translocates from the cytoplasm into the nucleus where it interacts with other transcription factors resulting in increased expression of over 2000 plant defense genes contributing to a pathogen resistance response.</p> <p>Results</p> <p>A putative <it>Theobroma cacao NPR1 </it>cDNA was isolated by RT-PCR using degenerate primers based on homologous sequences from <it>Brassica</it>, <it>Arabidopsis </it>and <it>Carica papaya</it>. The cDNA was used to isolate a genomic clone from <it>Theobroma cacao </it>containing a putative <it>TcNPR1 </it>gene. DNA sequencing revealed the presence of a 4.5 kb coding region containing three introns and encoding a polypeptide of 591 amino acids. The predicted TcNPR1 protein shares 55% identity and 78% similarity to <it>Arabidopsis </it>NPR1, and contains each of the highly conserved functional domains indicative of this class of transcription factors (BTB/POZ and ankyrin repeat protein-protein interaction domains and a nuclear localization sequence (NLS)). To functionally define the <it>TcNPR1 </it>gene, we transferred <it>TcNPR1 </it>into an <it>Arabidopsis npr1 </it>mutant that is highly susceptible to infection by the plant pathogen <it>Pseudomonas syringae </it>pv. tomato DC3000. Driven by the constitutive CaMV35S promoter, the cacao <it>TcNPR1 </it>gene partially complemented the <it>npr1 </it>mutation in transgenic <it>Arabidopsis </it>plants, resulting in 100 fold less bacterial growth in a leaf infection assay. Upon induction with SA, <it>TcNPR1 </it>was shown to translocate into the nucleus of leaf and root cells in a manner identical to <it>Arabidopsis </it>NPR1. Cacao NPR1 was also capable of participating in SA-JA signaling crosstalk, as evidenced by the suppression of JA responsive gene expression in <it>TcNPR1 </it>overexpressing transgenic plants.</p> <p>Conclusion</p> <p>Our data indicate that the <it>TcNPR1 </it>is a functional ortholog of <it>Arabidopsis NPR1</it>, and is likely to play a major role in defense response in cacao. This fundamental knowledge can contribute to breeding of disease resistant cacao varieties through the application of molecular markers or the use of transgenic strategies.</p

    Suvremeni putokazi razvitka industrije cijevi

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    First the paper presents a review of steel production of the tubes in world: possible potencial is about 110 × 106 the tons (35 × 106 seamless tubes, rest welding tubes). In 2007. y. was record volume of 88,6 ×106 tons in world; 6,5% of total production of steel in world. Ratio-weldeds tubes: seamless tubes 70:30%. Further in the article are presented urgent the problems of the pipe and tube industry.Prvi dio članka daje pregled proizvodnje čeličnih cijevi u svijetu: moguća je proizvodnost 110 × 106 tona (35 × 106 tona bešavnih cijevi, ostatak šavne cijevi). U 2007. god. bila je rekordna proizvodnja cijevi u svijetu 88,6 × 106 tona, tj. 6,5% od ukupne proizvodnje čelika u svijetu. Odnos – šavne cijevi: bešavne cijevi 70:30%. U nastavku članka su navedeni žurni problemi u industriji cijevi

    What is known about deferasirox chelation therapy in pediatric HSCT recipients: two case reports of metabolic acidosis

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    To date, in pediatric field, various hematological malignancies are increasingly treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Iron overload and systemic siderosis often occur in this particular cohort of patients and are associated with poor prognosis. We describe herein the case of two allo-HSCT patients, on treatment with deferasirox; they showed histopathological elements compatible with venoocclusive disease or vanishing bile duct syndrome in ductopenic evolution before deferasirox started. The first patient developed drug-induced liver damage with metabolic acidosis and the second one a liver impairment with Fanconi syndrome. After withdrawing deferasirox treatment, both patients showed improvement. Measurements of drug plasma concentrations were performed by HPLC assay. The reduction and consequent disappearance of symptoms after the suspension of deferasirox substantiate its role in inducing hepatic damage, probably enabling the diagnosis of drug-induced liver damage. But the difficulties in diagnosing drug-related toxicity must be underlined, especially in compromised subjects. For these reasons, in patients requiring iron-chelating therapy, close and careful drug therapeutic monitoring is strongly recommende

    Erratum to: Theobroma cacao L. pathogenesis-related gene tandem array members show diverse expression dynamics in response to pathogen colonization

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    The original version of the manuscript [1] contained an incorrectly named Criollo gene ID on chromosome 1 in the first sentence, under the subheading “Organization of PR gene families into tandem arrays”. The second gene on chromosome 1, Tc##_g######, should therefore be Tc01_g000020.The original version of the manuscript [1] contained an incorrectly named Criollo gene ID on chromosome 1 in the first sentence, under the subheading “Organization of PR gene families into tandem arrays”. The second gene on chromosome 1, Tc##_g######, should therefore be Tc01_g000020

    Genetic variability and structure of SNP haplotypes in the DMPK gene in Yakuts and other ethnic groups of northern Eurasia in relation to myotonic dystrophy

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    The genetic variability of the DMPK locus has been studied in relation to six SNP markers (rs2070736, rs572634, rs1799894, rs527221, rs915915, and rs10415988) in Yakuts with myotonic dystrophy (MD) in the Yakut population and in populations of northern Eurasia. Significant differences were observed in the allele frequencies between patients and a population sample of Yakuts for three SNP loci (rs915915, rs1799894, and rs0415988) associated with a high chance of disease manifestation. The odds ratios (OR) of MD development in representatives of the Yakut population for these three loci were 2.59 (95% CI, p = 0,004), 4.99 (95% CI, p = 0.000), and 3.15 (95% CI, p = 0.01), respectively. Haplotype TTTCTC, which is associated with MD, and haplotype GTCCTT, which was observed only in Yakut MD patients (never in MD patients of non-Yakut origin), were revealed. A low level of variability in the locus of DMRK gene in Yakuts (He = 0.283) compared with other examined populations was noted. An analysis of pairwise genetic relationships between populations revealed their significant differentiation for all the examined loci. In addition, a low level of differentiation in territorial groups of Yakut populations (FST = 0.79%), which was related to the high subdivision of the northern Eurasian population (FST = 11.83%), was observed

    Термоэлектрические явления и устройства в концепции Ландауэра–Датты–Лундстрома

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    С позиций концепции «снизу–вверх» транспортной модели Ландауэра–Датты–Лундстрома современной наноэлектроники рассматриваются термоэлектрические явления Зеебека и Пельтье и качественно обсуждаются закон Видемана–Франца, числа Лоренца и основные уравнения термоэлектричества с четырьмя транспортными коэффициентами (удельное сопротивление, коэффициенты Зеебека и Пельтье, электронная теплопроводность). С тех же позиций на примере 3D-резистора в диффузионном режиме анализируется работа термоэлектрических охладителя и генератора энергии с учётом лишь электронов, как реальных носителей тока, так и в рамках умозрительной, но удобной «дырочной» модели, вводятся и определяются понятия эффективности работы (КПД, фактора мощности и добротности) термоэлектрических устройств и рассматривается, каким образом транспортные коэффициенты зависят от свойств термиков.З позицій концепції «знизу–вгору» транспортної моделі Ландауера–Датти–Лундстрома сучасної наноелектроніки розглядаються термоелектричні явища Зеєбека і Пельтьє і якісно обговорюються закон Відеманна–Франца, Лоренцові числа й основні рівняння термоелектрики з чотирма транспортними коефіцієнтами (питомий опір, коефіцієнти Зеєбека і Пельтьє, електронна теплопровідність). З тих же позицій на прикладі 3D-резистора в дифузійному режимі аналізується робота термоелектричних охолоджувача і ґенератора енергії з урахуванням лише електронів, як реальних носіїв струму, так і в межах умоглядної, але зручної «діркової» моделі, вводяться і визначаються поняття ефективности роботи (ККД, фактора потужности і добротности) термоелектричних пристроїв і розглядається, яким чином транспортні коефіцієнти залежать від властивостей терміків.Based on the ‘bottom-to-top’ approach of the Landauer–Datta–Lundstrom transport model of state-of-the-art nanoelectronics, the thermoelectric Seebeck and Peltier phenomena are considered; the Wiedemann–Franz law and Lorenz numbers as well as the four transport coefficients (specific resistivity, Seebeck and Peltier coefficients, and electronic thermal conductivity) are qualitatively discussed. From the same positions for 3D-resistor within the diffusion regime, thermoelectric cooler and energy power generator are analysed with accounting only electrons as real current carriers as well as within the scope of the artificial but useful ‘hole’ model. Conceptions of operating performances (coefficient of efficiency, power factor, and figure of merit) for thermoelectric devices are introduced and defined, and dependences of transport coefficients on the properties of termics are discussed
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