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1.
Jiayin Song Brett F. Carver Carol Powers Liuling Yan Jaroslav Klápště Yousry A. El-Kassaby Charles Chen 《Molecular breeding : new strategies in plant improvement》2017,37(10):117
Crop improvement is a long-term, expensive institutional endeavor. Genomic selection (GS), which uses single nucleotide polymorphism (SNP) information to estimate genomic breeding values, has proven efficient to increasing genetic gain by accelerating the breeding process in animal breeding programs. As for crop improvement, with few exceptions, GS applicability remains in the evaluation of algorithm performance. In this study, we examined factors related to GS applicability in line development stage for grain yield using a hard red winter wheat (Triticum aestivum L.) doubled-haploid population. The performance of GS was evaluated in two consecutive years to predict grain yield. In general, the semi-parametric reproducing kernel Hilbert space prediction algorithm outperformed parametric genomic best linear unbiased prediction. For both parametric and semi-parametric algorithms, an upward bias in predictability was apparent in within-year cross-validation, suggesting the prerequisite of cross-year validation for a more reliable prediction. Adjusting the training population’s phenotype for genotype by environment effect had a positive impact on GS model’s predictive ability. Possibly due to marker redundancy, a selected subset of SNPs at an absolute pairwise correlation coefficient threshold value of 0.4 produced comparable results and reduced the computational burden of considering the full SNP set. Finally, in the context of an ongoing breeding and selection effort, the present study has provided a measure of confidence based on the deviation of line selection from GS results, supporting the implementation of GS in wheat variety development. 相似文献
2.
Marisa H. Miceli Tracey Churay Thomas Braun Carol A. Kauffman Daniel R. Couriel 《Mycopathologia》2017,182(5-6):495-504
Allogeneic hematopoietic cell transplant (HCT) recipients are at increased risk of invasive fungal infections (IFI), which are associated with a high mortality rate. We evaluated the impact of IFI in allogeneic HCT patients. In total, 541 consecutive allogeneic HCT recipients were included. The cumulative incidence of any IFI and mold infections at 1-year post-HCT was 10 and 7%, respectively. Median times to IFI and mold infection were 200 and 210 days, respectively. There was a trend toward fewer IFI and mold infections in the last several years. Both acute graft-versus-host disease (GVHD) (OR 1.83, p = 0.05) and corticosteroid duration (OR 1.0, p = 0.026) were significantly associated with increased risk of IFI, acute GVHD (OR 2.3, p = 0.027) emerged as the most important association with mold infections. Any IFI [HR 4.1 (2.79–6.07), p < 0.0001] and mold infections [HR 3.34 (2.1–5.1), p < 0.0001] were independently associated with non-relapse mortality (NRM). This association persisted in the setting of both acute and chronic GVHD. Corticosteroid treatment for >90 days was also significantly associated with higher NRM [HR 1.9 (1.3–2.6), p < 0.0001]. This study highlights the impact of IFI on NRM among HCT patients. The decrease in number of IFI and mold infections over the last several years may reflect the benefit of prophylaxis with mold-active antifungal agents. 相似文献
3.
Development and evaluation of the polymerase chain reaction to detect Mycoplasma genitalium 总被引:11,自引:0,他引:11
The polymerase chain reaction (PCR) was developed to detect Mycoplasma genitalium. Oligonucleotide primers were used to amplify a 374 bp region of the attachment protein of the mycoplasma. DNA from three strains of M. genitalium tested gave a characteristic PCR product which was not seen with DNA from any other source. As little as 10(-15) g of M. genitalium DNA could be detected and it was found in the vagina of progesterone-treated BALB/c mice inoculated with M. genitalium organisms later than they could be cultured from this site, but not in mice that never became colonised vaginally. 相似文献
4.
S Gilfillan S Aiso D Smilek D L Woodland E Palmer H O McDevitt 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(12):4074-4081
The effects of quantitative differences in class II cell surface expression have been difficult to address in intact animals. This study uses several lines of H-2s/s mice carrying an A beta k transgene that differ significantly in terms of class II cell surface expression. Due to inefficient chain pairing, mice carrying 60 to 65 copies of this transgene express only low levels of A alpha s/A beta k on the cell surface, and cell surface expression of the endogenous A alpha s/A beta s complex (and total Ia) is severely reduced (to 7-15% control levels). The significant decrease in class II cell surface expression in the thymic cortex of these mice did not affect the frequency of peripheral T cells expressing at least 10 distinct TCR V beta chains. However, T cell proliferative responses to the A alpha s/A beta s-restricted peptide MBP 89-101 were abrogated in high copy number A beta k mice. Experiments using bone marrow chimeras demonstrated that both inefficient Ag presentation and failure to positively select appropriate T cells contributed to this lack of response. Inefficient Ag presentation was clearly the dominant defect, and the density of class II cell surface expression required for positive selection appeared to be quite low. 相似文献
5.
6.
A unified framework to model the potential and realized distributions of invasive species within the invaded range 下载免费PDF全文
Tarek Hattab Carol X. Garzón‐López Michael Ewald Sandra Skowronek Raf Aerts Hélène Horen Boris Brasseur Emilie Gallet‐Moron Fabien Spicher Guillaume Decocq Hannes Feilhauer Olivier Honnay Pieter Kempeneers Sebastian Schmidtlein Ben Somers Ruben Van De Kerchove Duccio Rocchini Jonathan Lenoir 《Diversity & distributions》2017,23(7):806-819
7.
This article is part of a Special Issue Energy Balance. 相似文献
8.
9.
Joan M. Redd Anne-Catherine Lagarde Carol A. Kruse Donald Bellgrau 《Cancer immunology, immunotherapy : CII》1992,34(5):349-354
Summary We report the development of cytotoxic T lymphocytes specific for an allogeneic brain tumor in a rat model. DA strain cytotoxic T cell precursors stimulated by an allogeneic tumor (9L gliosarcoma) from the Fischer rat could generate a population of cytotoxic T lymphocytes that lysed the allogeneic 9L tumor but failed to lyse other targets, including Fischer concanavalin-A(ConA)-stimulated lymphoid blast targets. DA T cells depleted of reactivity to the Fischer haplotype (DA-f) retained reactivity to the 9L tumor, demonstrating that T cell precursors with specificity for normal Fischer alloantigens were not required for the generation of a response to the 9L Fischer tumor. The preferential lysis of the tumor target did not simply reflect a higher density of Fischer target antigens on the tumor than that found on normal Fischer ConA blast targets. First, the relative densities of class I antigen on the 9L tumor and normal Fischer ConA blasts were comparable. Second, cytotoxic T cells could not be generated from DA-f precursors when Fischer ConA blasts were used as stimulators. If DA-f T cells were simply responding to the higher density of Fischer antigen found on 9L tumor, it would have been expected that the ConA blasts expressing comparable levels of antigen to that found on the tumor would have generated cytotoxicity for both the 9L and ConA targets. We conclude that the cytotoxic T cells are specific for a determinant expressed only by the tumor. Such tumor-specific cytotoxic T cells could be useful in vivo for adoptive immunotherapy of brain tumors. 相似文献
10.
Paul A. Montagna Alexey L. Sadovski Scott A. King Kevin K. Nelson Terence A. Palmer Kenneth H. Dunton 《Wetlands Ecology and Management》2017,25(6):731-742
Water resource development has decreased water delivery to marshes in the Nueces Delta, Corpus Christi, Texas, USA by 45% since 1983, which has led to marsh degradation. Recent management actions will allow for partial hydrological restoration of the marsh, but there is a need to understand the dynamics and the interactive roles of climate and water cycle changes in order to predict changes in salt marshes in the future. In this study, a model of multi-species competition with respect to hydrological change was developed to perform modeling experiments of the effects of water elevation on development of marsh plant species. Nueces Delta plants were divided into two functional groups: (1) clonal stress tolerant plants (Batis maritima, Distichlis spicata, Monanthcloe littoralis, and Salicornia virginica), and (2) clonal dominants (Borrichia frutescens and Spartina alterniflora). Growth rates were calculated for three climate regimes (wet, moderate, and dry), and in three elevation locations (low, mid, and high marsh). The model predicts reductions in plant cover in both drought and moderate conditions. Marsh plant coverage increases only during wet conditions and when there is space available for plant expansion. It is concluded that changes in areal extent of the marsh largely depend on water flow and elevation, which in turn depends on the quantity of fresh water flowing into the marsh. However, under current climate and water management conditions, the marsh will degrade further. 相似文献