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971.
DNA Isolation and AFLP Fingerprinting of Nectarine and Peach Varieties (Prunus persica) 总被引：9，自引：0，他引：9
Manubens Augusto Lobos Sergio Jadue Yael Toro Manuel Messina Rosa Lladser Manuel Seelenfreund Daniela 《Plant Molecular Biology Reporter》1999,17(3):255-267
Traditional identification of peach and nectarine varieties relies on the assessment of agronomic traits of the adult plant. This leads to a significant delay of time, constraints to breeders in the surveillance of germplasm and a risk for fruit growers and exporters. We describe a method for rapid assessment of peach and nectarine varieties based on AFLP fingerprinting and extraction of high quality DNA. The best primer pairs were selected from 64 primer combinations that reliably distinguished 8 peach and 6 nectarine varieties. A graphical representation of the detected polymorphisms was shown to simplify the analysis. 相似文献
972.
Kallirroi Kotilea;Claudio Romano;Erasmo Miele;Angelika Kindermann;Yael Dolstra;Zrinjka Misak;Vaidotas Urbonas;Josef Sykora;Pedro Urruzuno;Alexander Krauthammer;Maria Rogalidou;Konstantina Dimakou;Tsili Zangen;Eleftheria Roma;Aglaia Zellos;María Luz Cilleruelo;Meline M'Rini;Patrick Bontems;Yasin Sahin;Marta Tavares;Tatevik Shahinyan;Biljana Vuletic;Nicolas Kalach;Michal Kori; ; 《Helicobacter》2024,29(3):e13092
Helicobacter pylori may be found during upper gastrointestinal endoscopy (UGE) performed to diagnose celiac disease (CeD), inflammatory bowel disease (IBD), and eosinophilic esophagitis (EoE). We aimed to describe the frequency of H. pylori in children undergoing UGE for CeD, IBD, and EoE and the number of children receiving eradication treatment. 相似文献
973.
974.
Anner Cohen Yael Hacham Yochai Welfe Soliman Khatib Jean‐Christophe Avice Rachel Amir 《The Plant journal : for cell and molecular biology》2020,102(2):246-261
With the objective of studying the role of glutathione reductase (GR) in the accumulation of cysteine and methionine, we generated transgenic tobacco and Arabidopsis lines overexpressing the cytosolic AtGR1 and the plastidic AtGR2 genes. The transgenic plants had higher contents of cysteine and glutathione. To understand why cysteine levels increased in these plants, we also used gr1 and gr2 mutants. The results showed that the transgenic plants have higher levels of sulfite, cysteine, glutathione and methionine, which are downstream to adenosine 5′ phosphosulfate reductase (APR) activity. However, the mutants had lower levels of these metabolites, while the sulfate content increased. A feeding experiment using 34SO42– also showed that the levels of APR downstream metabolites increased in the transgenic lines and decreased in gr1 compared with their controls. These findings, and the results obtained from the expression levels of several genes related to the sulfur pathway, suggest that GR plays an essential role in the sulfur assimilation pathway by supporting the activity of APR, the key enzyme in this pathway. GR recycles the oxidized form of glutathione (GSSG) back to reduce glutathione (GSH), which serves as an electron donor for APR activity. The phenotypes of the transgenic plants and the mutants are not significantly altered under non‐stress and oxidative stress conditions. However, when germinating on sulfur‐deficient medium, the transgenic plants grew better, while the mutants were more sensitive than the control plants. The results give substantial evidence of the yet unreported function of GR in the sulfur assimilation pathway. 相似文献
975.
Amber J. M. Jarrett Grant M. Cox Jochen J. Brocks Emmanuelle Grosjean Chris J. Boreham Dianne S. Edwards 《Geobiology》2019,17(4):360-380
The ca. 1.38 billion years (Ga) old Roper Group of the McArthur Basin, northern Australia, is one of the most extensive Proterozoic hydrocarbon‐bearing units. Organic‐rich black siltstones from the Velkerri Formation were deposited in a deep‐water sequence and were analysed to determine their organic geochemical (biomarker) signatures, which were used to interpret the microbial diversity and palaeoenvironment of the Roper Seaway. The indigenous hydrocarbon biomarker assemblages describe a water column dominated by bacteria with large‐scale heterotrophic reworking of the organic matter in the water column or bottom sediment. Possible evidence for microbial reworking includes a large unresolved complex mixture (UCM), high ratios of mid‐chained and terminally branched monomethyl alkanes relative to n‐alkanes—features characteristic of indigenous Proterozoic bitumen. Steranes, biomarkers for single‐celled and multicellular eukaryotes, were below detection limits in all extracts analysed, despite eukaryotic microfossils having been previously identified in the Roper Group, albeit largely in organically lean shallower water facies. These data suggest that eukaryotes, while present in the Roper Seaway, were ecologically restricted and contributed little to export production. The 2,3,4‐ and 2,3,6‐trimethyl aryl isoprenoids (TMAI) were absent or in very low concentration in the Velkerri Formation. The low abundance is primary and not caused by thermal destruction. The combination of increased dibenzothiophene in the Amungee Member of the Velkerri Formation and trace metal redox geochemistry suggests that degradation of carotenoids occurred during intermittent oxygen exposure at the sediment–water interface and/or the water column was rarely euxinic in the photic zone and likely only transiently euxinic at depth. A comparison of this work with recently published biomarker and trace elemental studies from other mid‐Proterozoic basins demonstrates that microbial environments, water column geochemistry and basin redox were heterogeneous. 相似文献
976.
Yael S. Rodger Alexandra Pavlova Steve Sinclair Melinda Pickup Paul Sunnucks 《Heredity》2021,126(5):846
Conservation management can be aided by knowledge of genetic diversity and evolutionary history, so that ecological and evolutionary processes can be preserved. The Button Wrinklewort daisy (Rutidosis leptorrhynchoides) was a common component of grassy ecosystems in south-eastern Australia. It is now endangered due to extensive habitat loss and the impacts of livestock grazing, and is currently restricted to a few small populations in two regions >500 km apart, one in Victoria, the other in the Australian Capital Territory and nearby New South Wales (ACT/NSW). Using a genome-wide SNP dataset, we assessed patterns of genetic structure and genetic differentiation of 12 natural diploid populations. We estimated intrapopulation genetic diversity to scope sources for genetic management. Bayesian clustering and principal coordinate analyses showed strong population genetic differentiation between the two regions, and substantial substructure within ACT/NSW. A coalescent tree-building approach implemented in SNAPP indicated evolutionary divergence between the two distant regions. Among the populations screened, the last two known remaining Victorian populations had the highest genetic diversity, despite having among the lowest recent census sizes. A maximum likelihood population tree method implemented in TreeMix suggested little or no recent gene flow except potentially between very close neighbours. Populations that were more genetically distinctive had lower genetic diversity, suggesting that drift in isolation is likely driving population differentiation though loss of diversity, hence re-establishing gene flow among them is desirable. These results provide background knowledge for evidence-based conservation and support genetic rescue within and between regions to elevate genetic diversity and alleviate inbreeding.Subject terms: Ecological genetics, Population genetics 相似文献
977.
978.
This study focuses on patterns of communication and interaction for peer support, which develop among parents of screen-positive children in the socio-medical space created by the diagnostic uncertainty of newborn screening, the limitations of established patient support groups and the daily challenges of screen-positive care management. Based on semi-structured interviews conducted in 2015–2017 with 34 Israeli parents whose child is screen positive, we describe and analyze the spontaneous grouping of parents using the WhatsApp instant messaging service for smartphones. These self-help groups did not reflect an attempt to forge an alternative movement of de-medicalization but rather to provide satisfactory answers to shared problems of care management under diagnostic uncertainty. These self-help groups are further discussed as a form of biosociality and lay expertise where elements of communication such as simplicity, reciprocity, and deliberative democracy serve as a complementary mirror-image of the asymmetrical patient–doctor communication. 相似文献
979.
980.