Helicobacter pylori is known to be an etiologic agent of gastritis and peptic ulcer disease in humans. However, the mechanism by which this organism acquires iron has not been studied. For this investigation, H. pylori was grown in iron-restricted medium. Siderophore production was not detected by chemical assays, and the strains were unable to use enterochelin and pyochelin for growth in low-iron media. Human lactoferrin supported full growth of the bacteria in media lacking other iron sources, but neither human transferrin, bovine lactoferrin, nor hen ovotransferrin served as a source for iron. Since lactoferrin was found in significant amounts in human stomach resections with superficial or atrophic gastritis, the iron acquisition system of H. pylori by the human lactoferrin receptor system may play a major role in the virulence of H. pylori infection.
Background and Aims: Based on parentage analysis of a large nuclear simple sequence repeat (SSR) marker database of grapevine genotypes, we propose the pedigree of several cultivars from southwestern France including Merlot, one of the world's major black winegrapes.
Methods and Results: The putative mother of Merlot, deduced from inheritance at 55 nuclear and three chloroplast microsatellite loci, is a non‐referenced and previously unknown cultivar, first sampled some years ago in northern Brittany where vines were cultivated at the end of the Middle Ages, and then identified in four places in Charentes. Considering both the name used by the growers of this grape and the literature, we have named it Magdeleine Noire des Charentes. The putative father of Merlot is Cabernet Franc, already involved in the parentage of Cabernet‐Sauvignon. Further analysis of genetic relationships leads us to propose the kinship group of Merlot composed, among others, of Carmenère (Gros Cabernet × Cabernet Franc), Merlot Blanc (Merlot × Folle Blanche), Cot (Magdeleine Noire des Charentes × Prunelard) and Mourtès (Magdeleine Noire des Charentes × Penouille).
Conclusions: These results shed new light on the origin of Merlot and on the relationships among several cultivars from southwestern France.
Significance of the Study: Our discovery of the key genetic role of a previously unknown cultivar in the origins of some significant cultivars reinforces the importance of deep exploration, before it is too late, to discover original genotypes which have not yet been collected or referenced.
Our findings highlight the importance and value of user-centered usability testing of a patient application implemented in "real-world" conditions. To achieve adoption and sustained use by patients, the app should meet patients' needs while also efficiently improving the quality of MedRec.
Based on the number of new reports during the last two decades, bacterial blight of onion (Allium cepa) is considered an emerging disease. The causal agent, Xanthomonas axonopodis pv. allii, is pathogenic to several Allium species after inoculation, but outbreaks worldwide have been primarily reported on onion. We describe a unique epidemiological situation in Réunion Island, France, with concomitant outbreaks on three Allium species, onion, leek (A. porrum), and garlic (A. sativum). There was no host specialization within Allium spp. among strains associated with the three host species. Based on amplified fragment length polymorphism (AFLP) and restriction fragment length polymorphism, strains associated with these outbreaks in Réunion Island were highly related genetically to strains isolated from diseased plant samples and contaminated seed lots in the neighboring island of Mauritius, where the disease has occurred since 1984. All AFLP haplotypes were identified as X. axonopodis pv. allii based on polymerase chain reaction analysis using specific primers, biochemical tests, and/or pathogenicity tests. Two genetically related groups of strains (A and B) that can be distinguished by AFLP, differential utilization of three carbon sources, and xanthomonadin pigment production were detected initially after establishment of the pathogen. In less than 10 years after the establishment of the pathogen there was nearly an extinction of group A strains in Réunion Island, suggesting differences in fitness between strains in the two groups.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.