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681.
The use of antibiotic or herbicide resistant genes as selection markers for production of transgenic plants and their continuous
presence in the final transgenics has been a serious problem for their public acceptance and commercialization. MAT (multi-auto-transformation)
vector system has been one of the different strategies to excise the selection marker gene and produce marker-free transgenic
plants. In the present study, ipt (isopentenyl transferase) gene was used as a selection marker gene. A chitinase gene, ChiC (isolated from Streptomyces griseus strain HUT 6037) was used as a gene of interest. ChiC gene was cloned from the binary vector, pEKH1 to an ipt-type MAT vector, pMAT21 by gateway cloning and transferred to Agrobacterium
tumefaciens strain EHA105. The infected tuber discs of potato were cultured on hormone- and antibiotic-free MS medium. Seven of the 35
explants infected with the pMAT21/ChiC produced shoots. The same antibiotic- and hormones-free MS medium was used in subcultures of the shoots (ipt like and normal shoots). Molecular analyses of genomic DNA from transgenic plants confirmed the integration of gene of interest
and excision of the selection marker in 3 of the 7 clones. Expression of ChiC gene was confirmed by Northern blot and western blot analyses. Disease-resistant assay of the marker-free transgenic, in
vitro and greenhouse-grown plants exhibited enhanced resistance against Alternaria solani (early blight), Botrytis cinerea (gray mold) and Fusarium oxysporum (Fusarium wilt). From these results it could be concluded that ipt gene can be used as a selection marker to produce marker-free disease-resistant transgenic potato plants on PGR- and antibiotic-free
MS medium. 相似文献
682.
Oleg Pisarenko Valentine Shulzhenko Irina Studneva Larisa Serebryakova Oksana Veselova 《International journal of peptide research and therapeutics》2017,23(3):333-341
Chemically modified peptide apelin-12 (MA) with enhanced resistance to degradation by proteolytic enzymes is able to protect the heart against myocardial ischemia and reperfusion. This study was aimed to explore the role of mitochondrial ATP-sensitive K+-channels (mitoKATP) in effects of MA on myocardial energy state and membrane integrity in ischemia/reperfusion (I/R) injury. Isolated perfused working rat hearts were used to simulate global ischemia and reperfusion. Acute myocardial infarction was induced by coronary artery occlusion followed by restoration of coronary blood flow in anesthetized rats. Myocardial infarct size and cardiac dysfunction were used as indices of I/R injury at the end of reperfusion. Co-infusion of 5-hydroxydecanoate (5HD), the mitoKATP blocker, along with MA before ischemia significantly decreased functional recovery of isolated hearts as compared to administration of MA alone. These effects were accompanied by increased LDH release in the myocardial effluent, reduced restoration of myocardial ATP, AN, Cr, adenylate energy charge (AEC), and lactate accumulation. Coadministration of 5HD and MA at the onset of reperfusion substantially reduced infarct-limiting effect of the peptide in rats in vivo and increased the plasma LDH and CK-MB activity compared with MA treatment. Additionally, 5HD abolished MA influence on the metabolic state of the area at risk (AAR) at the end of reperfusion. In this case, the contents of metabolites and AEC in the AAR did not differ significantly from the values in control. Therefore, restoration of myocardial energy metabolism and sarcolemma integrity via activation of mitoKATP may be of critical importance for MA-induced protection against I/R injury. 相似文献
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Hualan Liu Anthony L. Shiver Morgan N. Price Hans K. Carlson Valentine V. Trotter Yan Chen Veronica Escalante Jayashree Ray Kelsey E. Hern Christopher J. Petzold Peter J. Turnbaugh Kerwyn Casey Huang Adam P. Arkin Adam M. Deutschbauer 《Cell reports》2021,34(9):108789
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Mario AlvarezJimenez Peter Koval Lianne Schmaal Sarah Bendall Shaunagh O'Sullivan Daniela Cagliarini Simon D'Alfonso Simon Rice Lee Valentine David L. Penn Chris Miles Penni Russon Jessica Phillips Carla McEnery Reeva Lederman Eoin Killackey Cathrine Mihalopoulos Cesar GonzalezBlanch Tamsyn Gilbertson Shalini Lal Sue Maree Cotton Helen Herrman Patrick D. McGorry John F.M. Gleeson 《World psychiatry》2021,20(2):233
This study aimed to determine whether, following two years of specialized support for first‐episode psychosis, the addition of a new digital intervention (Horyzons) to treatment as usual (TAU) for 18 months was more effective than 18 months of TAU alone. We conducted a single‐blind randomized controlled trial. Participants were people with first‐episode psychosis (N=170), aged 16‐27 years, in clinical remission and nearing discharge from a specialized service. They were randomly assigned (1:1) to receive Horyzons plus TAU (N=86) or TAU alone (N=84) between October 2013 and January 2017. Horyzons is a novel, comprehensive digital platform merging: peer‐to‐peer social networking; theory‐driven and evidence‐informed therapeutic interventions targeting social functioning, vocational recovery and relapse prevention; expert clinician and vocational support; and peer support and moderation. TAU involved transfer to primary or tertiary community mental health services. The primary outcome was social functioning at 18 months as measured by the Personal and Social Performance Scale (PSP). Forty‐seven participants (55.5%) in the Horyzons plus TAU group logged on for at least 6 months, and 40 (47.0%) for at least 9 months. Social functioning remained high and stable in both groups from baseline to 18‐month follow‐up, with no evidence of significant between‐group differences (PSP mean difference: –0.29, 95% CI: –4.20 to 3.63, p=0.77). Participants in the Horyzons group had a 5.5 times greater increase in their odds to find employment or enroll in education compared with those in TAU (odds ratio, OR=5.55, 95% CI: 1.09‐28.23, p=0.04), with evidence of a dose‐response effect. Moreover, participants in TAU were twice as likely to visit emergency services compared to those in the Horyzons group (39% vs. 19%; OR=0.31, 95% CI: 0.11‐0.86, p=0.03, number needed to treat, NNT=5). There was a non‐significant trend for lower hospitalizations due to psychosis in the Horyzons group vs. TAU (13% vs. 27%; OR=0.36, 95% CI: 0.11‐1.08, p=0.07, NNT=7). So, although we did not find a significant effect of Horyzons on social functioning compared with TAU, the intervention was effective in improving vocational or educational attainment, a core component of social recovery, and in reducing usage of hospital emergency services, a key aim of specialized first‐episode psychosis services. Horyzons holds significant promise as an engaging and sustainable intervention to provide effective vocational and relapse prevention support for young people with first‐episode psychosis beyond specialist services. 相似文献
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Richard J. Cogdell Irene Durant Jane Valentine J.Gordon Lindsay Karin Schmidt 《BBA》1983,722(3):427-435
The photosynthetic membranes of two strains of Rhodopseudomonas acidophila (7750 and 7050) have been resolved into their constituent light-harvesting pigment-protein complexes. Four different types of antenna complexes (B880, B800–830 and two types of B800–850) have been isolated and partially purified. In each case the light-harvesting pigments (bacteriochlorophyll a and carotenoids) are bound to rather low molecular weight polypeptides (in the 5000–9000 region). 相似文献