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511.
Bodo Linz Helen M. Windsor John P. Gajewski Caylie M. Hake Daniela I. Drautz Stephan C. Schuster Barry J. Marshall 《PloS one》2013,8(12)
The human gastric pathogen Helicobacter pylori is usually acquired during childhood and, in the absence of treatment, chronic infection persists through most of the host''s life. However, the frequency and importance of H. pylori transmission between adults is underestimated. Here we sequenced the complete genomes of H. pylori strains that were transmitted between spouses and analysed the genomic changes. Similar to H. pylori from chronic infection, a significantly high proportion of the determined 31 SNPs and 10 recombinant DNA fragments affected genes of the hop family of outer membrane proteins, some of which are known to be adhesins. In addition, changes in a fucosyltransferase gene modified the LPS component of the bacterial cell surface, suggesting strong diversifying selection. In contrast, virulence factor genes were not affected by the genomic changes. We propose a model of the genomic changes that are associated with the transmission and adaptation of H. pylori to a new human host. 相似文献
512.
Jan Hauke Andrea Schild Antje Neugebauer Alexandra Lappa Julia Fricke Sascha Fauser Stefanie R?sler Andrea Pannes Dirk Zarrinnam Janine Altmüller Susanne Motameny Gudrun Nürnberg Peter Nürnberg Eric Hahnen Bodo B. Beck 《PloS one》2013,8(10)
Cone-rod dystrophies (CORDs) represent a heterogeneous group of monogenic diseases leading to early impairment of vision. The majority of CORD entities show autosomal modes of inheritance and X-linked traits are comparably rare. So far, three X-chromosomal entities were reported (CORDX1, -X2 and -X3). In this study, we analysed a large family of German origin with solely affected males over three generations showing a CORDX-like phenotype. Due to the heterogeneity of cone-rod dystrophies, we performed a combined linkage and X-exome sequencing approach and identified a novel large intragenic in-frame deletion encompassing exons 18 to 26 within the CACNA1F gene. CACNA1F is described causative for CORDX3 in a single family originating from Finland and alterations in this gene have not yet been reported in other CORDX pedigrees. Our data independently confirm CACNA1F as the causative gene for CORDX3-like phenotypes and detailed clinical characterization of the family expands the knowledge about the phenotypic spectrum of deleterious CACNA1F alterations. 相似文献
513.
Bodo Trognitz Emile Cros Sophie Assemat Fabrice Davrieux Nelly Forestier-Chiron Eusebio Ayestas Aldo Kuant Xavier Scheldeman Michael Hermann 《PloS one》2013,8(1)
The sensory quality and the contents of quality-determining chemical compounds in unfermented and fermented cocoa from 100 cacao trees (individual genotypes) representing groups of nine genotype spectra (GG), grown at smallholder plantings in the municipality of Waslala, Nicaragua, were evaluated for two successive harvest periods. Cocoa samples were fermented using a technique mimicking recommended on-farm practices. The sensory cocoa quality was assessed by experienced tasters, and seven major chemical taste compounds were quantified by near infrared spectrometry (NIRS). The association of the nine, partially admixed, genotype spectra with the analytical and sensory quality parameters was tested. The individual parameters were analyzed as a function of the factors GG and harvest (including the date of fermentation), individual trees within a single GG were used as replications. In fermented cocoa, significant GG-specific differences were observed for methylxanthines, theobromine-to-caffeine (T/C) ratio, total fat, procyanidin B5 and epicatechin, as well as the sensory attributes global score, astringency, and dry fruit aroma, but differences related to harvest were also apparent. The potential cocoa yield was also highly determined by the individual GG, although there was significant tree-to-tree variation within every single GG. Non-fermented samples showed large harvest-to-harvest variation of their chemical composition, while differences between GG were insignificant. These results suggest that selection by the genetic background, represented here by groups of partially admixed genotype spectra, would be a useful strategy toward enhancing quality and yield of cocoa in Nicaragua. Selection by the GG within the local, genetically segregating populations of seed-propagated cacao, followed by clonal propagation of best-performing individuals of the selected GG could be a viable alternative to traditional propagation of cacao by seed from open pollination. Fast and gentle air-drying of the fermented beans and their permanent dry storage were an efficient and comparatively easy precondition for high cocoa quality. 相似文献
514.
The mechanism of lignin carbohydrate complex formation by addition of polysaccharides on quinone methide (QM) generated during
lignin polymerisation was investigated using a model approach. Dehydrogenation polymers (DHPs, lignin model compounds) were
synthesized from coniferyl alcohol in the presence of a glucuronoarabinoxylan (GAX) extracted from oat spelts, by Zutropfverfahren
(ZT) and Zulaufverfahren (ZL) methods. The methods ZT and ZL differed in their distribution of QM over the reaction period
but generated roughly the same QM amount. Steric exclusion chromatography of the ZT and ZL reaction products showed that only
the ZT reaction produced high molar mass compounds. Covalent linkages in the ZT reaction involving ether bonds between GAX
moiety and α carbon of the lignin monomer were confirmed by 13C NMR and xylanase-based fractionation. The underlying phenomena were further investigated by examining the interactions between
GAX and DHP in sorption experiments. GAX and DHPs were shown to interact to form hydrophobic aggregates. In the ZT process,
slow addition permitted polymer reorganisation which led to dehydration around the lignin-like growing chains thereby limiting
the addition of water on the quinone methide formed during polymerisation and thus favoured lignin–carbohydrate complex (LCC)
formation. 相似文献
515.
Bodo M Muzi G Bellucci C Lilli C Calvitti M Lumare A Dell'Omo M Gambelunghe A Baroni T Murgia N 《Journal of biological regulators and homeostatic agents》2007,21(3-4):97-104
The small dimension and particle shape of silica in gypsum used to prepare moulds for lost wax casting might be responsible for the high prevalence of silicosis in gold jewellery. To test this hypothesis, human pulmonary epithelial cell (BEAS-2B) cultures were exposed to two samples of silica with different crystal micro-morphologies: Silica Powder (Silica P) which is used in casting gold jewellery, and no powder Silica (Silica F). Extracellular matrix (ECM) production was evaluated using radio-labelled precursors and quantified by RT-PCR analysis. Expression of basic fibroblast growth factor (FGF2) and its receptor (FGFR2) was also evaluated. The results demonstrated Silica P particles had a very fine lamellar crystalline structure while Silica F was characterized by larger rounded crystals. Silica P stimulated collagen production significantly more than Silica F and downregulated laminin and metalloprotease expression. Both silica samples down-regulated FGF2 but only Silica F enhanced FGF2 receptor expression. In conclusion each Silica sample promoted a profibrotic lung microenvironment in a different manner and also elicited different FGF2 signalling pathways. The data confirm that different micromorphology of Silica particles affects the fibrogenic potential and the molecular mechanisms of dust pathogenicity. 相似文献
516.
Mounir R Durieux A Bodo E Allard C Simon JP Achbani EH El-Jaafari S Douira A Jijakli MH 《Biotechnology letters》2007,29(4):553-559
Aureobasidium pullulans (de Bary) Arnaud (Ach 1-1) was grown in a glucose fed-batch fermentor to 106 g dry wt l−1 in 48 h. The cells were dried in a fluidized bed dryer with a final viability of 62%. After 7 months at 4°C, the viability
was 28% of the initial value (= 2.3 × 1010 c.f.u. g−1 dry matter). A protection level of 89% was achieved with the biomass preparation at 1 × 108 c.f.u. ml−1 after 28 and 7 days for apples stored respectively at 5 and 25°C against Penicillium expansum. Our process is suitable to produce large quantities of the strain Ach 1-1 as biological control agent for apple preservation. 相似文献
517.
Charles Emile Ramarokoto Anna Overgaard Kildemoes Bodo Sahondra Randrianasolo Pascaline Ravoniarimbinina Vololomboahangy Elisabeth Ravaoalimalala Peter Leutscher Eyrun Floerecke Kjetland Birgitte Jyding Vennervald 《PLoS neglected tropical diseases》2014,8(7)
Background
Genital granulomas induced by Schistosoma haematobium eggs can manifest as different lesion types visible by colposcopy; rubbery papules (RP), homogenous sandy patches (HSP) and grainy sandy patches (GSP). Pronounced tissue eosinophilia is a candidate marker for active S. haematobium pathology, as viable schistosome egg granulomas often are eosinophil rich. Here it was investigated whether eosinophil granule proteins ECP (eosinophil cationic protein) and EPX (eosinophil protein-X) in urine and genital lavage can be used as markers for active FGS lesions.Methods
Uro-genital samples from 118 Malagasy women were analysed for ECP and EPX by standard sandwich avidin/biotin amplified ELISA.Principal findings
The women with RP lesions had significantly higher levels of ECP and EPX in both lavage and urine. Furthermore, women with RP lesions were significantly younger than those with GSP. This could indicate that RP lesions might be more recently established and thus represent an earlier inflammatory lesion stage.Conclusion
ECP in genital lavage might be a future tool aiding the identification of FGS pathology at a stage where reversibility remains a possibility following praziquantel treatment. 相似文献518.
Tamara Laube Pilar Cortés Montserrat Llagostera Salvador Alegret María Isabel Pividori 《Applied microbiology and biotechnology》2014,98(4):1795-1805
This work explores the use of the phage P22 in a phagomagnetic immunoassay for the rapid detection of Salmonella. The covalent attachment of wild-type phages was performed on two different magnetic carriers: carboxyl-activated magnetic nanoparticles (300 nm) and tosyl-activated magnetic microparticles (2.8 μm). The bacteria were captured and preconcentrated by the phage-modified magnetic particles, followed by the detection using specific anti-Salmonella antibodies conjugated to horseradish peroxidase as an optical reporter. Outstanding selectivity and sensitivity was obtained with this approach, achieving detection limits of 19 CFU mL?1 in 2.5 h without any pre-enrichment, in milk samples. Moreover, if the samples were pre-enriched for 6 h, the method was able to detect as low as 1.4 CFU in 25 mL of milk. Therefore, the proposed strategy based on the combined use of phagomagnetic separation with immunological labeling is promising as a rapid and simple method for food safety. 相似文献
519.
520.
Poongodi Geetha-Loganathan Suresh Nimmagadda Bodo Christ Ruijin Huang Martin Scaal 《BMC developmental biology》2010,10(1):32