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11.
In Western Europe, many pond owners introduce amphibians for ornamental purposes. Although indigenous amphibians are legally protected in most European countries, retailers are circumventing national and international legislation by selling exotic nonprotected sibling species. We investigated to what extent non‐native species of the European water frog complex (genus Pelophylax) have become established in Belgium, using morphological, mitochondrial and nuclear genetic markers. A survey of 87 sampling sites showed the presence of non‐native water frogs at 47 locations, mostly Marsh frogs (Pelophylax ridibundus). Surprisingly, at least 19% of all these locations also harboured individuals with mitochondrial haplotypes characteristic of Anatolian water frogs (Pelophylax cf. bedriagae). Nuclear genotyping indicated widespread hybridization and introgression between P. ridibundus and P. cf. bedriagae. In addition, water frogs of Turkish origin obtained through a licensed retailer, also contained P. ridibundus and P. cf. bedriagae, with identical haplotypes to the wild Belgian populations. Although P. ridibundus might have invaded Belgium by natural range expansion from neighbouring countries, our results suggest that its invasion was at least partly enhanced by commercial trade, with origins as far as the Middle East. Also the invasion and rapid spread of Anatolian lineages, masked by their high morphological similarity to P. ridibundus, is likely the result of unregulated commercial trade. We expect that Anatolian frogs will further invade the exotic as well as the native range of P. ridibundus and other Pelophylax species elsewhere in Western and Central Europe, with risks of large‐scale hybridization and introgression.  相似文献   
12.
The aim of this paper was to compare the effect of haplotype definition on the precision of QTL-mapping and on the accuracy of predicted genomic breeding values. In a multiple QTL model using identity-by-descent (IBD) probabilities between haplotypes, various haplotype definitions were tested i.e. including 2, 6, 12 or 20 marker alleles and clustering base haplotypes related with an IBD probability of > 0.55, 0.75 or 0.95. Simulated data contained 1100 animals with known genotypes and phenotypes and 1000 animals with known genotypes and unknown phenotypes. Genomes comprising 3 Morgan were simulated and contained 74 polymorphic QTL and 383 polymorphic SNP markers with an average r2 value of 0.14 between adjacent markers. The total number of haplotypes decreased up to 50% when the window size was increased from two to 20 markers and decreased by at least 50% when haplotypes related with an IBD probability of > 0.55 instead of > 0.95 were clustered. An intermediate window size led to more precise QTL mapping. Window size and clustering had a limited effect on the accuracy of predicted total breeding values, ranging from 0.79 to 0.81. Our conclusion is that different optimal window sizes should be used in QTL-mapping versus genome-wide breeding value prediction.  相似文献   
13.
The objectives of this study were to estimate the incidence and describe the pattern and severity of training injuries in taekwondo, and to compare pattern and severity of training injuries with competition injuries. One hundred and fifty-two active Australian amateur taekwondo athletes, aged 12 years or over, completed an online survey comprising questions on training exposure and injury history over the preceding 12 months. The main outcome measures were: overall injury incidence rate per athlete-year; training injury incidence rate per athlete-year, per 1000 athlete-training-sessions, and per 1000 athlete-hours of training; injury severity; and injury proportions by anatomical region and by type of injury. Injury incidence rates were calculated with 95% confidence intervals using standard methods, while injury proportions were compared using Fisher''s exact test. The vast majority (81.5%) of taekwondo injuries in an average athlete-year occurred during training. The training injury incidence rate was estimated to be 1.6 (95% CI: 1.4, 1.9) per athlete-year, 11.8 (95% CI: 10.4, 13.4) per 1000 athlete-training-sessions, and 7.0 (95% CI: 6.1, 7.9) per 1000 athlete-hours of training. Among athletes with five or fewer injuries, the severity and injury pattern of training injuries were, by and large, the same as for competition injuries. Approximately sixty percent (60.3%) of training injuries required treatment by a health professional. Considering the burden of training injuries exceeds that of competition injuries, taekwondo governing bodies and stakeholders are encouraged to devote more efforts towards the identification of risk factors for, and prevention of, training injuries in the sport of taekwondo.  相似文献   
14.

Background  

Suitable biomarkers associated with the development of delirium are still not known. Urinary proteomics has successfully been applied to identify novel biomarkers associated with various disease states, but its value has not been investigated in delirium patients.  相似文献   
15.
Natural killer (NK) cells are an innate lymphoid cell lineage characterized by their capacity to provide rapid effector functions, including cytokine production and cytotoxicity. Here, we identify the Ikaros family member, Aiolos, as a regulator of NK-cell maturation. Aiolos expression is initiated at the point of lineage commitment and maintained throughout NK-cell ontogeny. Analysis of cell surface markers representative of distinct stages of peripheral NK-cell maturation revealed that Aiolos was required for the maturation in the spleen of CD11bhighCD27 NK cells. The differentiation block was intrinsic to the NK-cell lineage and resembled that found in mice lacking either T-bet or Blimp1; however, genetic analysis revealed that Aiolos acted independently of all other known regulators of NK-cell differentiation. NK cells lacking Aiolos were strongly hyper-reactive to a variety of NK-cell-mediated tumor models, yet impaired in controlling viral infection, suggesting a regulatory function for CD27 NK cells in balancing these two arms of the immune response. These data place Aiolos in the emerging gene regulatory network controlling NK-cell maturation and function.  相似文献   
16.
The experimental autoimmune encephalomyelitis (EAE) model resembles certain aspects of multiple sclerosis (MScl), with common features such as motor dysfunction, axonal degradation, and infiltration of T-cells. We studied the cerebrospinal fluid (CSF) proteome in the EAE rat model to identify proteomic changes relevant for MScl disease pathology. EAE was induced in male Lewis rats by injection of myelin basic protein (MBP) together with complete Freund's adjuvant (CFA). An inflammatory control group was injected with CFA alone, and a nontreated group served as healthy control. CSF was collected at day 10 and 14 after immunization and analyzed by bottom-up proteomics on Orbitrap LC-MS and QTOF LC-MS platforms in two independent laboratories. By combining results, 44 proteins were discovered to be significantly increased in EAE animals compared to both control groups, 25 of which have not been mentioned in relation to the EAE model before. Lysozyme C1, fetuin B, T-kininogen, serum paraoxonase/arylesterase 1, glutathione peroxidase 3, complement C3, and afamin are among the proteins significantly elevated in this rat EAE model. Two proteins, afamin and complement C3, were validated in an independent sample set using quantitative selected reaction monitoring mass spectrometry. The molecular weights of the identified differentially abundant proteins indicated an increased transport across the blood-brain barrier (BBB) at the peak of the disease, caused by an increase in BBB permeability.  相似文献   
17.
Data processing forms an integral part of biomarker discovery and contributes significantly to the ultimate result. To compare and evaluate various publicly available open source label-free data processing workflows, we developed msCompare, a modular framework that allows the arbitrary combination of different feature detection/quantification and alignment/matching algorithms in conjunction with a novel scoring method to evaluate their overall performance. We used msCompare to assess the performance of workflows built from modules of publicly available data processing packages such as SuperHirn, OpenMS, and MZmine and our in-house developed modules on peptide-spiked urine and trypsin-digested cerebrospinal fluid (CSF) samples. We found that the quality of results varied greatly among workflows, and interestingly, heterogeneous combinations of algorithms often performed better than the homogenous workflows. Our scoring method showed that the union of feature matrices of different workflows outperformed the original homogenous workflows in some cases. msCompare is open source software (https://trac.nbic.nl/mscompare), and we provide a web-based data processing service for our framework by integration into the Galaxy server of the Netherlands Bioinformatics Center (http://galaxy.nbic.nl/galaxy) to allow scientists to determine which combination of modules provides the most accurate processing for their particular LC-MS data sets.  相似文献   
18.

Background  

APOBEC3 (A3) proteins deaminate DNA cytosines and block the replication of retroviruses and retrotransposons. Each A3 gene encodes a protein with one or two conserved zinc-coordinating motifs (Z1, Z2 or Z3). The presence of one A3 gene in mice (Z2–Z3) and seven in humans, A3A-H (Z1a, Z2a-Z1b, Z2b, Z2c-Z2d, Z2e-Z2f, Z2g-Z1c, Z3), suggests extraordinary evolutionary flexibility. To gain insights into the mechanism and timing of A3 gene expansion and into the functional modularity of these genes, we analyzed the genomic sequences, expressed cDNAs and activities of the full A3 repertoire of three artiodactyl lineages: sheep, cattle and pigs.  相似文献   
19.
We describe a platform for the comparative profiling of urine using reversed-phase liquid chromatography-mass spectrometry (LC-MS) and multivariate statistical data analysis. Urinary compounds were separated by gradient elution and subsequently detected by electrospray Ion-Trap MS. The lower limit of detection (5.7-21 nmol/L), within-day (2.9-19%) and between-day (4.8-19%) analytical variation of peak areas, linearity (R2: 0.918-0.999), and standard deviation for retention time (<0.52 min) of the method were assessed by means of addition of seven 3-8 amino acid peptides (0-500 nmol/L). Relating the amount of injected urine to the area under the curve (AUC) of the chromatographic trace at 214 nm better reduced the coefficient of variation (CV) of the AUC of the total ion chromatogram (CV = 10.1%) than relating it to creatinine (CV = 38.4%). LC-MS data were processed, and the common peak matrix was analyzed by principal component analysis (PCA) after supervised classification by the nearest shrunken centroid algorithm. The feasibility of the method to discriminate urine samples of differing compositions was evaluated by (i) addition of seven peptides at nanomolar concentrations to blank urine samples of different origin and (ii) a study of urine from kidney patients with and without proteinuria. (i) The added peptides were ranked as highly discriminatory peaks despite significant biological variation. (ii) Ninety-two peaks were selected best discriminating proteinuric from nonproteinuric samples, of which 6 were more intense in the majority of the proteinuric samples. Two of these 6 peaks were identified as albumin-derived peptides, which is in accordance with the early rise of albumin during glomerular proteinuria. Interestingly, other albumin-derived peptides were nondiscriminatory indicating preferential proteolysis at some cleavage sites.  相似文献   
20.
本文报告用转基因细胞B43分泌的乙型肝炎病毒表面抗原主蛋白经纯化制成的87-4批重组疫苗进行临床接种观察的结果,同时用8723-1批血源疫苗作对照。疫苗接种采用0、1、2月各接种1针的方案。重组疫苗共接种111名8~13岁儿童,分为20μg、10μg及5μg 3组,血源疫苗分为20μg、10μg 2组。所有儿童接种前检查乙型肝炎病毒表面抗原、抗体及核心抗体均阴性.20μg组1针后1个月,重组疫苗阳转率60.5%,血源疫苗为31%;2针后1个月,两种疫苗的阳转率分别为100%和72.4%;血源疫苗3针后1个月阳转率也仅79.3%。3针后1个月两种疫苗的抗体几何平均滴度(GMT)分别为492.7和207.4mIU。但重组疫苗6个月后血清抗体的GMT为628mIU。10μg组1针后1个月的阳转率重组疫苗为21.7%,血源疫苗为20.9%;2针后1个月分别为87%及62.8%;3针后1个月分别为100%及81.4%。抗体GMT分别为163.7和129.6mIU.5μg组的重组疫苗免疫后6个月100%阳转,其GMT为56mIU。结论认为无论从阳转率或几何平均滴度分析判断,重组疫苗均优于血源疫苗。  相似文献   
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