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Muhammad A. Javed Somayyeh Poshtiban Denis Arutyunov Stephane Evoy Christine M. Szymanski 《PloS one》2013,8(7)
Campylobacter jejuni and Campylobacter coli are the most common bacterial causes of foodborne gastroenteritis which is occasionally followed by a debilitating neuropathy known as Guillain-Barré syndrome. Rapid and specific detection of these pathogens is very important for effective control and quick treatment of infection. Most of the diagnostics available for these organisms are time consuming and require technical expertise with expensive instruments and reagents to perform. Bacteriophages bind to their host specifically through their receptor binding proteins (RBPs), which can be exploited for pathogen detection. We recently sequenced the genome of C. jejuni phage NCTC12673 and identified its putative host receptor binding protein, Gp047. In the current study, we localized the receptor binding domain to the C-terminal quarter of Gp047. CC-Gp047 could be produced recombinantly and was capable of agglutinating both C. jejuni and C. coli cells unlike the host range of the parent phage which is limited to a subset of C. jejuni isolates. The agglutination procedure could be performed within minutes on a glass slide at room temperature and was not hindered by the presence of buffers or nutrient media. This agglutination assay showed 100% specificity and the sensitivity was 95% for C. jejuni (n = 40) and 90% for C. coli (n = 19). CC-Gp047 was also expressed as a fusion with enhanced green fluorescent protein (EGFP). Chimeric EGFP_CC-Gp047 was able to specifically label C. jejuni and C. coli cells in mixed cultures allowing for the detection of these pathogens by fluorescent microscopy. This study describes a simple and rapid method for the detection of C. jejuni and C. coli using engineered phage RBPs and offers a promising new diagnostics platform for healthcare and surveillance laboratories. 相似文献
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Farshad Shadanloo Mohammad Hasan Najafi Sayed Morteza Hosseini Mehdi Hajian Mohsen Forouzanfar Kamran Ghaedi Parvaneh Abedi Somaye Ostadhosseini Laleh Hosseini Morad‐Pasha Eskandari‐Nasab Mohammad Hossein Nasr Esfahani 《Molecular reproduction and development》2010,77(10):868-875
In relation to the growing recent interest in the establishment of sperm‐mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0–500 ng) of pcDNA/his/Lac‐Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live‐immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA‐incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X‐Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live‐immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live‐immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. Mol. Reprod. Dev. 77:868–875, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Roberto Mendoza-Londono Somayyeh Fahiminiya Jacek Majewski CareRare Canada Consortium Martine Tétreault Javad Nadaf Peter Kannu Etienne Sochett Andrew Howard Jennifer Stimec Lucie Dupuis Paul Roschger Klaus Klaushofer Telma Palomo Jean Ouellet Hadil Al-Jallad John?S. Mort Pierre Moffatt Sergei Boudko Hans-Peter B?chinger Frank Rauch 《American journal of human genetics》2015,96(6):979-985
Secreted protein, acidic, cysteine-rich (SPARC) is a glycoprotein that binds to collagen type I and other proteins in the extracellular matrix. Using whole-exome sequencing to identify the molecular defect in two unrelated girls with severe bone fragility and a clinical diagnosis of osteogenesis imperfecta type IV, we identified two homozygous variants in SPARC (GenBank: ; c.497G>A [p.Arg166His] in individual 1; c.787G>A [p.Glu263Lys] in individual 2). Published modeling and site-directed mutagenesis studies had previously shown that the residues substituted by these mutations form an intramolecular salt bridge in SPARC and are essential for the binding of SPARC to collagen type I. The amount of SPARC secreted by skin fibroblasts was reduced in individual 1 but appeared normal in individual 2. The migration of collagen type I alpha chains produced by these fibroblasts was mildly delayed on SDS-PAGE gel, suggesting some overmodification of collagen during triple helical formation. Pulse-chase experiments showed that collagen type I secretion was mildly delayed in skin fibroblasts from both individuals. Analysis of an iliac bone sample from individual 2 showed that trabecular bone was hypermineralized on the material level. In conclusion, these observations show that homozygous mutations in SPARC can give rise to severe bone fragility in humans. NM_003118.3相似文献
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It is a common practice to rest vitrified-warmed matured oocytes for 1-3 h, as a treatment to recover spindle and cytoskeleton, before commencing a further treatment. Vitrified-warmed matured oocytes, however, are very sensitive and may resume meiosis spontaneously during this recommended rest time. Therefore, the aim of this study was to assess spindle and chromosome status as well as developmental competence of vitrified in vitro matured sheep oocytes activated parthenogenetically, either 0 h (immediately) or 2 h (delayed) after warming. There was no significant effect of post-warming interval on the proportion of degenerated oocytes. Evaluation of chromosomes and meiotic spindle configuration showed that 11.11% of oocytes in the immediate group and 8.82% of oocytes in the delayed group had normal chromosomal alignment on well-structured spindles, compared to non-vitrified group (79.41%). Meanwhile, majority of the chromosomal abnormalities in the immediate and delayed groups were categorized as absent (unobservable) (77.78%) and anaphase II (70.59%), respectively. Oocytes in immediately activated group showed significantly higher blastocyst rate (28.86%) compared to delayed activated group (16.47%). In conclusion, the results suggest that post-warming interval may have important consequence on meiotic progression and parthenogenetic activation of vitrified oocytes. In sheep, it appears that chemical activation without having to await microtubule reorganization improves embryonic development. 相似文献
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Asgari V Hosseini SM Ostadhosseini S Hajian M Azhdari ZT Mosaie M Nasr-Esfahani MH 《Molecular reproduction and development》2012,79(7):434-444
Oocyte vitrification and assisted oocyte activation have increasingly important roles in assisted reproductive technology. Yet, an important area of concern with matured oocyte cryobiology is that elements of oocytes intimately involved in metaphase‐II arrest may be modified by cryopreservation. By comparing different cellular characteristics of unvitrified, vitrified‐warmed, and unvitrified‐activated oocytes, the present study investigated how vitrification‐warming process may affect developmental competence of in vitro‐matured sheep oocytes following parthenogenetic activation. Structural, ultrastructural, and molecular analyses indicated that the characteristics of vitrified‐warmed oocytes vastly differed from fresh oocytes, instead resembling unvitrified‐activated oocytes. For unvitrified oocytes, the highest blastocyst yield (41.8 ± 0.6%) was achieved using the maximum ionomycin concentration (5 µM), and importantly, the duration of ionomycin treatment was not of utmost importance at this concentration. In contrast, the maximum blastocyst yield of vitrified‐warmed oocytes (28.4 ± 1.4%) was achieved with a minimal duration of ionomycin treatment (1 min), and further extending the duration dramatically reduced developmental potential of vitrified‐warmed oocytes. These results suggested that vitrified‐warmed oocytes may need an activation protocol different from unvitrified oocytes. In this respect, unvitrified oocytes were more sensitive to the concentration rather than the duration of ionomycin treatment when compared with vitrified oocytes, which were sensitive to the treatment duration. These results may provide a platform to improve the potential applications of vitrified oocytes in medicine and agriculture. Mol. Reprod. Dev. 79:434–444, 2012. © Wiley Periodicals, Inc. 相似文献
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Somayyeh Fahiminiya Valérie Labas Sylvie Chastant-Maillard Nadine Gérard 《Reproductive biology and endocrinology : RB&E》2010,8(1):132