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131.
132.
A substantial fraction of the genome of most eukaryotes, including those of metazoan parasites, is predicted to comprise repetitive sequences. Mobile genetic elements (MGEs) will make up much of these repetitive sequences, particularly the interspersed sequences. This article reviews information on MGEs that have colonized the genomes of metazoan parasites (i.e. parasites of parasites). Helminth and mosquito genomes, in particular, are compared with those of better-understood model organisms. MGEs from the genomes of metazoan parasites can be expected to have practical uses in transgenesis and epidemiological studies. 相似文献
133.
1,4-Disubstituted imidazoles are potential antibacterial agents functioning as inhibitors of enoyl acyl carrier protein reductase (FabI) 总被引:4,自引:0,他引:4
Heerding DA Chan G DeWolf WE Fosberry AP Janson CA Jaworski DD McManus E Miller WH Moore TD Payne DJ Qiu X Rittenhouse SF Slater-Radosti C Smith W Takata DT Vaidya KS Yuan CC Huffman WF 《Bioorganic & medicinal chemistry letters》2001,11(16):2061-2065
1,4-Disubstituted imidazole inhibitors of Staphylococcus aureus and Escherichia coli enoyl acyl carrier protein reductase (FabI) have been identified. Crystal structure data shows the inhibitor 1 bound in the enzyme active site of E. coli FabI. 相似文献
134.
Saravanan Thavamanikumar Luke J. McManus Peter K. Ades Gerd Bossinger Desmond J. Stackpole Richard Kerr Sara Hadjigol Jules S. Freeman René E. Vaillancourt Peng Zhu Josquin F. G. Tibbits 《Tree Genetics & Genomes》2014,10(6):1661-1678
The moderate to high levels of nucleotide diversity and low linkage disequilibrium found in many forest tree species make them ideal candidates for association mapping. Here, we report candidate gene-based association mapping results for complex wood quality and growth traits in Eucalyptus globulus Labill. ssp. globulus, the most widely grown eucalypt in temperate regions of the world. Ninety-eight single nucleotide polymorphisms (SNPs) from 20 wood quality candidate genes were assayed in a discovery population consisting of 385 trees sourced from a provenance-progeny trial. Twenty-five selected SNPs with significant associations (P?0.05) in the discovery population were assayed for validation in 296 trees sourced from an independent second-generation breeding trial. To account for background genetic structure, mixed models were used in the association analyses. Two associations identified in the discovery population were independently supported in the validation testing. However, combining the discovery and validation results in a combined analysis, we discovered nine stable marker-trait associations for seven traits. These associations link underlying complex wood and growth phenotypes to earlier putative selection signatures opening new avenues to accelerate the dissection of these traits. 相似文献
135.
Xing-Wei Ni Donald P. McManus Zhong-Zi Lou Ji-Fei Yang Hong-Bin Yan Li Li Hong-Min Li Quan-Yuan Liu Chun-Hua Li Wan-Gui Shi Yan-Lei Fan Xu Liu Jin-Zhong Cai Meng-Tong Lei Bao-Quan Fu Yu-Rong Yang Wan-Zhong Jia 《PloS one》2014,9(7)
Background
Cystic echinococcosis is highly prevalent in northwest China. A cost-effective, easy to operate diagnostic tool with high sensitivity and specificity would greatly facilitate the monitoring of Echinococcus infections in canine definitive hosts.Methods
The primers used in the LAMP assay were based on the mitochondrial nad5 gene of E. granulosus sensu stricto (E. granulosus s.s., or E.g.s.s.) and were designed using Primer Explorer V4 software. The developed LAMP assay was compared with a conventional PCR method, copro-ELISA and microscopy, using the faeces of dogs experimentally infected with E.g.s.s., and field-collected faeces of domestic dogs including 190 from Qinghai province highly endemic for E.g.s.s. and 30 controls from an area in Gansu, where a domestic dog de-worming program was in operation.Results
The positivity rates obtained for the field-collected faecal samples were 12.6%, 1.6% and 2.1% by the LAMP, PCR and copro-ELISA assays, respectively. All samples obtained from the control dogs were negative. Compared with the conventional PCR, the LAMP assay provided 88.8% specificity and 100% sensitivity. The higher sensitivity of the LAMP method was also shown by the fact that it could detect the presence of laboratory challenge dog infections of E. granulsous s.s. four days earlier than the PCR method. Three copro-samples shown positive by the commercial copro-ELISA were all negative by LAMP, PCR and microscopy, which suggests these samples may have originated from another infection rather than E. granulsous s.s., possibly E. shiquicus or E. Canadensis, which is also present in China.Conclusions
We have developed a potentially useful surveillance tool for determining the prevalence of canine E. granulosus s.s. infections in the field. The LAMP assay may lead to a more cost-effective and practicable way of tracking Echinococcus infections in canids, especially when combined with the copro-ELISA. 相似文献136.
Background
Around ten percent of the population have been reported as having Chronic Kidney Disease (CKD), which is associated with increased cardiovascular mortality. Few previous studies have ascertained the chronicity of CKD. In the UK, a payment for performance (P4P) initiative incentivizes CKD (stages 3–5) recognition and management in primary care, but the impact of this has not been assessed.Methods and Findings
Using data from 426 primary care practices (population 2,707,130), the age standardised prevalence of stages 3–5 CKD was identified using two consecutive estimated Glomerular Filtration Rates (eGFRs) seven days apart. Additionally the accuracy of practice CKD registers and the relationship between accurate identification of CKD and the achievement of P4P indicators was determined. Between 2005 and 2009, the prevalence of stages 3–5 CKD increased from 0.3% to 3.9%. In 2009, 30,440 patients (1.1% unadjusted) fulfilled biochemical criteria for CKD but were not on a practice CKD register (uncoded CKD) and 60,705 patients (2.2% unadjusted) were included on a practice CKD register but did not fulfil biochemical criteria (miscoded CKD). For patients with confirmed CKD, inclusion in a practice register was associated with increasing age, male sex, diabetes, hypertension, cardiovascular disease and increasing CKD stage (p<0.0001). Uncoded CKD patients compared to miscoded patients were less likely to achieve performance indicators for blood pressure (OR 0.84, 95% CI 0.82–0.86 p<0.001) or recorded albumin-creatinine ratio (OR 0.73, 0.70–0.76, p<0.001).Conclusions
The prevalence of stages 3–5 CKD, using two laboratory reported eGFRs, was lower than estimates from previous studies. Clinically significant discrepancies were identified between biochemically defined CKD and appearance on practice registers, with misclassification associated with sub-optimal care for some people with CKD. 相似文献137.
138.
N F Dawson D J Craik A M McManus S G Dashper E C Reynolds G W Tregear L Otvos J D Wade 《Journal of peptide science》2000,6(1):19-25
The 32-residue peptide, RK-1, a novel kidney-derived three disulfide-bonded member of the antimicrobial alpha-defensin family, was synthesized by the continuous flow Fmoc-solid phase method. The crude, cleaved and S-reduced linear peptide was both efficiently folded and oxidized in an acidic solution of aqueous dimethyl sulfoxide. Following purification of the resulting product, it was shown by a variety of analytical techniques, including matrix assisted laser desorption time of flight mass spectrometry, to possess a very high degree of purity. The disulfide bond pairing of the synthetic peptide was determined by 1H-NMR spectroscopy and confirmed to be a Cys1-Cys6, Cys2-Cys4, Cys3-Cys5 arrangement similar to other mammalian alpha-defensin peptides. The synthetic RK-1 was also shown to inhibit the growth of Escherichia coli type strain NCTC 10418. 相似文献
139.
Yi Mu Catherine A. Gordon Remigio M. Olveda Allen G. Ross David U. Olveda Jessica M. Marsh Donald P. McManus Pengfei Cai 《PLoS neglected tropical diseases》2022,16(7)
BackgroundSchistosoma japonicum is one of three major species of blood flukes causing schistosomiasis, a disease, which continues to be a major public health issue in the Philippines. SjSAP4, a member of a multigene family of saposin-like proteins, is a recognized immunodiagnostic biomarker for schistosomiasis japonica. This study aimed to identify linear B-cell epitopes on SjSAP4 and to validate their potential as components of a multi-epitope assay for the serological diagnosis of schistosomiasis japonica.MethodologySjSAP4-derived peptides were expressed as GST-peptide-fused proteins and these were Western blot probed with human serum samples from S. japonicum Kato-Katz (KK)-positive individuals and uninfected controls. A core epitope was further identified by Western blotting through probing a series of truncated peptides with the schistosomiasis patient sera. The diagnostic performance of the core epitope-containing peptides and the full-length SjSAP4 was evaluated by enzyme-linked immunosorbent assay (ELISA) using a panel of sera collected from subjects resident in a schistosomiasis-endemic area of the Philippines.Main findingsAs a result of the peptide mapping, one peptide (P15) was found to be highly immunogenic in the KK-positive individuals. We subsequently showed that -S163QCSLVGDIFVDKYLD178- is a core B-cell epitope of P15. Subsequent ELISAs incorporating SjSAP4, SjSAP4-Peptide and SjSP-13V2-Peptide showed a sensitivity of 94.0%, 46.0% and 74.0%, respectively, and a specificity of 97.1%, 100% and 100%, respectively. Notably, complementary recognition of the B-cell epitopes (SjSAP4-Peptide and SjSP-13V2-Peptide) was observed in a subset of the KK-positive individuals. A dual epitope-ELISA (SjSAP4-Peptide + SjSP-13V2-Peptide-ELISA) showed a diagnostic sensitivity of 84.0% and a specificity of 100%.Conclusions/SignificanceIn this study, -S163QCSLVGDIFVDKYLD178- was identified as a dominant linear B-cell epitope on SjSAP4. This peptide and the complementary recognition of other B-cell epitopes using sera from different KK-positive individuals can provide the basis of developing a multi-epitope assay for the serological diagnosis of schistosomiasis. 相似文献
140.
Diwen Liang George B. McManus Qing Wang Xian Sun Zhiwei Liu Senjie Lin Yufeng Yang 《Ecology and evolution》2022,12(5)
Genetic differentiations and phylogeographical patterns of small organisms may be shaped by spatial isolation, environmental gradients, and gene flow. However, knowledge about genetic differentiation of rotifers at the intercontinental scale is still limited. Polyarthra dolichoptera and P. vulgaris are cosmopolitan rotifers that are tolerant to environmental changes, offering an excellent model to address the research gap. Here, we investigated the populations in Southeastern China and eastern North America and evaluated the phylogeographical patterns from their geographical range sizes, geographic–genetic distance relationships and their responses to spatial‐environmental factors. Using the mitochondrial cytochrome c oxidase subunit I gene as the DNA marker, we analyzed a total of 170 individuals. Our results showed that some putative cryptic species, also known as entities were widely distributed, but most of them were limited to single areas. The divergence of P. dolichoptera and P. vulgaris indicated that gene flow between continents was limited while that within each continent was stronger. Oceanographic barriers do affect the phylogeographic pattern of rotifers in continental waters and serve to maintain genetic diversity in nature. The genetic distance of P. dolichoptera and P. vulgaris populations showed significant positive correlation with geographic distance. This might be due to the combined effects of habitat heterogeneity, long‐distance colonization, and oceanographic barriers. Furthermore, at the intercontinental scale, spatial distance had a stronger influence than environmental variables on the genetic differentiations of both populations. Wind‐ and animal‐mediated transport and even historical events of continental plate tectonics are potential factors for phylogeography of cosmopolitan rotifers. 相似文献