Seamless Genome Editing in Rice via Gene Targeting and Precise Marker Elimination.
Nishizawa-Yokoi, Ayako; Saika, Hiroaki; Toki, Seiichi
2016-01-01
Positive-negative selection using hygromycin phosphotransferase (hpt) and diphtheria toxin A-fragment (DT-A) as positive and negative selection markers, respectively, allows enrichment of cells harboring target genes modified via gene targeting (GT). We have developed a successful GT system employing positive-negative selection and subsequent precise marker excision via the piggyBac transposon derived from the cabbage looper moth to introduce desired modifications into target genes in the rice genome. This approach could be applied to the precision genome editing of almost all endogenous genes throughout the genome, at least in rice.
A Novel Yeast Genomics Method for Identifying New Breast Cancer Susceptibility
2005-05-01
selectable marker and tracing this marker through several passages in nonselective medium. The selectable marker will be the hygromycin phosphotransferase ... hygromycin and sensitivity to (32), thereby providing both positive and negative selectivity. The assay involved measurement of the frequency of gancyclovir
Pheochromocytoma diagnosed pathologically with previous negative serum markers.
Heavner, Matthew G; Krane, Louis S; Winters, Shira M; Mirzazadeh, Majid
2015-10-01
Patients presenting with adrenal masses require workup with catecholamine or metabolite measurements to rule out pheochromocytoma. There is a select portion of patients with marker negative pheochromocytoma. The aim of this study is to compare patient characteristics and presentations between marker positive and marker negative tumors. We performed an IRB-approved retrospective chart review of 88 cases of pheochromocytoma excised at our institution from 1995 to 2013. We considered any abnormal elevation in diagnostic test to be marker-positive. Seventy-eight cases had laboratory results available. Among these, seven had no elevations in laboratory testing. There was no difference in age or tumor size, but marker-negative patients had higher BMI than marker-positive patients. Marker negative patients were more likely to present with vertigo/dizziness (P = 0.003). Neither was more likely to have a genetic syndrome associated with risk of pheochromocytoma. Marker-negative pheochromocytoma is uncommon, representing 9% of cases in our series. Of patients with adrenal masses or presentation suggesting catecholamine excess with normal labs, those with vertigo/dizziness may warrant a metaiodobenzylguanidine scan or repeat testing to avoid missing pheochromocytoma. Clinicians may need a high degree of suspicion for pheochromocytoma in patients with negative testing and elevated BMI. © 2015 Wiley Periodicals, Inc.
Li, Li; Tacke, Eckhard; Hofferbert, Hans-Reinhardt; Lübeck, Jens; Strahwald, Josef; Draffehn, Astrid M; Walkemeier, Birgit; Gebhardt, Christiane
2013-04-01
Tuber yield, starch content, starch yield and chip color are complex traits that are important for industrial uses and food processing of potato. Chip color depends on the quantity of reducing sugars glucose and fructose in the tubers, which are generated by starch degradation. Reducing sugars accumulate when tubers are stored at low temperatures. Early and efficient selection of cultivars with superior yield, starch yield and chip color is hampered by the fact that reliable phenotypic selection requires multiple year and location trials. Application of DNA-based markers early in the breeding cycle, which are diagnostic for superior alleles of genes that control natural variation of tuber quality, will reduce the number of clones to be evaluated in field trials. Association mapping using genes functional in carbohydrate metabolism as markers has discovered alleles of invertases and starch phosphorylases that are associated with tuber quality traits. Here, we report on new DNA variants at loci encoding ADP-glucose pyrophosphorylase and the invertase Pain-1, which are associated with positive or negative effect with chip color, tuber starch content and starch yield. Marker-assisted selection (MAS) and marker validation were performed in tetraploid breeding populations, using various combinations of 11 allele-specific markers associated with tuber quality traits. To facilitate MAS, user-friendly PCR assays were developed for specific candidate gene alleles. In a multi-parental population of advanced breeding clones, genotypes were selected for having different combinations of five positive and the corresponding negative marker alleles. Genotypes combining five positive marker alleles performed on average better than genotypes with four negative alleles and one positive allele. When tested individually, seven of eight markers showed an effect on at least one quality trait. The direction of effect was as expected. Combinations of two to three marker alleles were identified that significantly improved average chip quality after cold storage and tuber starch content. In F1 progeny of a single-cross combination, MAS with six markers did not give the expected result. Reasons and implications for MAS in potato are discussed.
Spelt, Lidewij; Sasor, Agata; Ansari, Daniel; Hilmersson, Katarzyna Said; Andersson, Roland
2018-01-01
To assess the expression of cancer stem cell (CSC) markers CD44, CD133 and CD24 in colon cancer liver metastases and analyse their predictive value for overall survival (OS) and disease-free survival (DFS) after liver resection. Patients operated on for colon cancer liver metastases were included. CSC marker expression was determined through immunohistochemistry analysis. OS and DFS were compared between marker-positive and marker-negative patients. Multivariate analysis was performed to select predictive variables for OS and DFS. CD133-positive patients had a worse DFS than CD133-negative patients, with a median DFS of 12 and 25 months (p=0.051). Multivariate analysis selected CD133 expression as a significant predictor for DFS. CD44 and CD24 were not found to predict OS or DFS. CD133 expression in colonic liver metastases is a negative prognostic factor for DFS after liver resection. In the future, CD133 could be used as a biomarker for risk stratification, and possibly for developing novel targeted therapy. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
BAPJ69-4A: a yeast two-hybrid strain for both positive and negative genetic selection.
Shaffer, Hally Anne; Rood, Michael Kenneth; Kashlan, Badar; Chang, Eileen I-ling; Doyle, Donald Francis; Azizi, Bahareh
2012-10-01
Genetic selection systems, such as the yeast two-hybrid system, are efficient methods to detect protein-protein and protein-ligand interactions. These systems have been further developed to assess negative interactions, such as inhibition, using the URA3 genetic selection marker. Previously, chemical complementation was used to assess positive selection in Saccharomyces cerevisiae. In this work, a new S. cerevisiae strain, called BAPJ69-4A, containing three selective markers ADE2, HIS3, and URA3 as well as the lacZ gene controlled by Gal4 response elements, was developed and characterized using the retinoid X receptor (RXR) and its ligand 9-cis retinoic acid (9cRA). Further characterization was performed using RXR variants and the synthetic ligand LG335. To assess the functionality of the strain, RXR was compared to the parent strain PJ69-4A in adenine, histidine, and uracil selective media. In positive selection, associating partners that lead to cell growth were observed in all media in the presence of ligand, whereas partners that did not associate due to the absence of ligand displayed no growth. Conversely, in negative selection, partners that did not associate in 5-FOA medium did not display cell death due to the lack of expression of the URA3 gene. The creation of the BAPJ69-4A yeast strain provides a high-throughput selection system, called negative chemical complementation, which can be used for both positive and negative selection, providing a fast, powerful tool for discovering novel ligand receptor pairs for applications in drug discovery and protein engineering. Copyright © 2012 Elsevier B.V. All rights reserved.
Kunnari, Sari; Savinainen-Makkonen, Tuula; Leonard, Laurence B.; Mäkinen, Leena; Tolonen, Anna-Kaisa
2015-01-01
Children with specific language impairment (SLI) have difficulty expressing subject-verb agreement. However, in many languages, tense is fused with agreement, making it difficult to attribute the problem to agreement in particular. In Finnish, negative markers are function words that agree with the subject in person and number but do not express tense, providing an opportunity to assess the status of agreement in a more straightforward way. Fifteen Finnish-speaking preschoolers with SLI, 15 age controls, and 15 younger controls responded to items requiring negative markers in first person singular and plural, and third person singular and plural. The children with SLI were less accurate than both typically developing groups. However, their problems were limited to particular person-number combinations. Furthermore, the children with SLI appeared to have difficulty selecting the form of the lexical verb that should accompany the negative marker, suggesting that agreement was not the sole difficulty. PMID:24588468
Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit
2013-01-01
Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.
Internal amplification control of PCR for the Glu1-Dx5 allele in wheat.
Heim, H N; Vieira, E S N; Polo, L R T; Lima, N K; Silva, G J; Linde, G A; Colauto, N B; Schuster, I
2017-08-17
One of the limiting factors in using dominant markers is the unique amplification of the target fragment. Therefore, failures in polymerase chain reaction (PCR) or non-amplifications can be interpreted as an absence of the allele. The possibility of false negatives implies in reduced efficiency in the selection process in genetic breeding programs besides the loss of valuable genetic material. Thus, this study aimed to evaluate the viability of a microsatellite marker as an internal amplification control with a dominant marker for the wheat Glu1-Dx5 gene. A population of 77 wheat cultivars/breeding lines was analyzed. Fourteen microsatellite markers were analyzed in silico regarding the formation of dimers and clamps. The biplex reaction conditions were optimized, and the Xbarc117 marker was selected as the internal amplification control with a Glu1-Dx5 marker in wheat. It was concluded that the Xbarc117 microsatellite marker was effective in the simultaneous amplification with a dominant Glu1-Dx5 marker, making biplex PCR viable in wheat for the studied markers.
Vaz, Candida; Tanavde, Vivek; Lakshmipathy, Uma
2014-01-01
Induced pluripotent stem cells (iPSCs) are promising tools for disease research and cell therapy. One of the critical steps in establishing iPSC lines is the early identification of fully reprogrammed colonies among unreprogrammed fibroblasts and partially reprogrammed intermediates. Currently, colony morphology and pluripotent stem cell surface markers are used to identify iPSC colonies. Through additional clonal characterization, we show that these tools fail to distinguish partially reprogrammed intermediates from fully reprogrammed iPSCs. Thus, they can lead to the selection of suboptimal clones for expansion. A subsequent global transcriptome analysis revealed that the cell adhesion protein CD44 is a marker that differentiates between partially and fully reprogrammed cells. Immunohistochemistry and flow cytometry confirmed that CD44 is highly expressed in the human parental fibroblasts used for the reprogramming experiments. It is gradually lost throughout the reprogramming process and is absent in fully established iPSCs. When used in conjunction with pluripotent cell markers, CD44 staining results in the clear identification of fully reprogrammed cells. This combination of positive and negative surface markers allows for easier and more accurate iPSC detection and selection, thus reducing the effort spent on suboptimal iPSC clones. PMID:24416407
The JH1 Haplotype-a newly discovered marker for infertility in the jersy breed
USDA-ARS?s Scientific Manuscript database
The focus on production traits in genetic selection programs with little consideration for traits associated with reproduction has contributed to the decline in reproductive function. Moreover, there is a negative genetic correlation between milk yield and reproduction so that selection for yield ca...
Lu, Xia; Luan, Sheng; Hu, Long Yang; Mao, Yong; Tao, Ye; Zhong, Sheng Ping; Kong, Jie
2016-06-01
The Kuruma prawn, Marsupenaeus japonicus, is one of the most promising marine invertebrates in the industry in Asia, Europe and Australia. However, the increasing global temperatures result in considerable economic losses in M. japonicus farming. In the present study, to select genetically improved animals for the sustainable development of the Kuruma prawn industry, a high-resolution genetic linkage map and quantitative trait locus (QTL) identification were performed using the RAD technology. The maternal map contained 5849 SNP markers and spanned 3127.23 cM, with an average marker interval of 0.535 cM. Instead, the paternal map contained 3927 SNP markers and spanned 3326.19 cM, with an average marker interval of 0.847 cM. The consensus map contained 9289 SNP markers and spanned 3610.90 cM, with an average marker interval of 0.388 cM and coverage of 99.06 % of the genome. The markers were grouped into 41 linkage groups in the maps. Significantly, negative correlation was detected between high-temperature tolerance (UTT) and body weight (BW). The QTL mapping revealed 129 significant QTL loci for UTT and four significant QTL loci for BW at the genome-wide significance threshold. Among these QTLs, 129 overlapped with linked SNPs, and the remaining four were located in regions between contiguous SNPs. They explained the total phenotypic variance ranging from 8.9 to 12.4 %. Because of a significantly negative correlation between growth and high-temperature tolerance, we demonstrate that this high-resolution linkage map and QTLs would be useful for further marker-assisted selection in the genetic improvement of M. japonicus.
Nilsson, Anders K; Andersson, Mats X
2017-01-01
A striking and unexpected biochemical phenotype was found in an insertion mutant line in the model plant Arabidopsis thaliana . One of two investigated insertion mutant lines in the gene encoding the phosphate transporter PHT4;1 demonstrated a prominent loss of trienoic fatty acids, whereas the other insertion line was indistinguishable from wild type in this aspect. We demonstrate that the loss of trienoic fatty acids was due to a remnant inactive negative selection marker gene in this particular transposon tagged line, pht4;1-3 . This constitutes a cautionary tale that warns of the importance to confirm the loss of this type of selection markers and the importance of verifying the relationship between a phenotype and genotype by more than one independent mutant line or alternatively genetic complementation.
NASA Astrophysics Data System (ADS)
Yu, Yuan; Tong, Qi; Li, Zhongxia; Tian, Jinhai; Wang, Yizhi; Su, Feng; Wang, Yongsheng; Liu, Jun; Zhang, Yong
2014-02-01
PhiC31 integrase-mediated gene delivery has been extensively used in gene therapy and animal transgenesis. However, random integration events are observed in phiC31-mediated integration in different types of mammalian cells; as a result, the efficiencies of pseudo attP site integration and evaluation of site-specific integration are compromised. To improve this system, we used an attB-TK fusion gene as a negative selection marker, thereby eliminating random integration during phiC31-mediated transfection. We also excised the selection system and plasmid bacterial backbone by using two other site-specific recombinases, Cre and Dre. Thus, we generated clean transgenic bovine fetal fibroblast cells free of selectable marker and plasmid bacterial backbone. These clean cells were used as donor nuclei for somatic cell nuclear transfer (SCNT), indicating a similar developmental competence of SCNT embryos to that of non-transgenic cells. Therefore, the present gene delivery system facilitated the development of gene therapy and agricultural biotechnology.
CombiROC: an interactive web tool for selecting accurate marker combinations of omics data.
Mazzara, Saveria; Rossi, Riccardo L; Grifantini, Renata; Donizetti, Simone; Abrignani, Sergio; Bombaci, Mauro
2017-03-30
Diagnostic accuracy can be improved considerably by combining multiple markers, whose performance in identifying diseased subjects is usually assessed via receiver operating characteristic (ROC) curves. The selection of multimarker signatures is a complicated process that requires integration of data signatures with sophisticated statistical methods. We developed a user-friendly tool, called CombiROC, to help researchers accurately determine optimal markers combinations from diverse omics methods. With CombiROC data from different domains, such as proteomics and transcriptomics, can be analyzed using sensitivity/specificity filters: the number of candidate marker panels rising from combinatorial analysis is easily optimized bypassing limitations imposed by the nature of different experimental approaches. Leaving to the user full control on initial selection stringency, CombiROC computes sensitivity and specificity for all markers combinations, performances of best combinations and ROC curves for automatic comparisons, all visualized in a graphic interface. CombiROC was designed without hard-coded thresholds, allowing a custom fit to each specific data: this dramatically reduces the computational burden and lowers the false negative rates given by fixed thresholds. The application was validated with published data, confirming the marker combination already originally described or even finding new ones. CombiROC is a novel tool for the scientific community freely available at http://CombiROC.eu.
Markers of preparatory attention predict visual short-term memory performance.
Murray, Alexandra M; Nobre, Anna C; Stokes, Mark G
2011-05-01
Visual short-term memory (VSTM) is limited in capacity. Therefore, it is important to encode only visual information that is most likely to be relevant to behaviour. Here we asked which aspects of selective biasing of VSTM encoding predict subsequent memory-based performance. We measured EEG during a selective VSTM encoding task, in which we varied parametrically the memory load and the precision of recall required to compare a remembered item to a subsequent probe item. On half the trials, a spatial cue indicated that participants only needed to encode items from one hemifield. We observed a typical sequence of markers of anticipatory spatial attention: early attention directing negativity (EDAN), anterior attention directing negativity (ADAN), late directing attention positivity (LDAP); as well as of VSTM maintenance: contralateral delay activity (CDA). We found that individual differences in preparatory brain activity (EDAN/ADAN) predicted cue-related changes in recall accuracy, indexed by memory-probe discrimination sensitivity (d'). Importantly, our parametric manipulation of memory-probe similarity also allowed us to model the behavioural data for each participant, providing estimates for the quality of the memory representation and the probability that an item could be retrieved. We found that selective encoding primarily increased the probability of accurate memory recall; that ERP markers of preparatory attention predicted the cue-related changes in recall probability. Copyright © 2011. Published by Elsevier Ltd.
Dangoudoubiyam, Sriveny; Zhang, Zijing; Howe, Daniel K
2014-09-01
Sarcocystis neurona is an apicomplexan parasite that causes severe neurological disease in horses and marine mammals. The Apicomplexa are all obligate intracellular parasites that lack purine biosynthesis pathways and rely on the host cell for their purine requirements. Hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK) are key enzymes that function in two complementary purine salvage pathways in apicomplexans. Bioinformatic searches of the S. neurona genome revealed genes encoding HXGPRT, AK and all of the major purine salvage enzymes except purine nucleoside phosphorylase. Wild-type S. neurona were able to grow in the presence of mycophenolic acid (MPA) but were inhibited by 6-thioxanthine (6-TX), suggesting that the pathways involving either HXGPRT or AK are functional in this parasite. Prior work with Toxoplasma gondii demonstrated the utility of HXGPRT as a positive-negative selection marker. To enable the use of HXGPRT in S. neurona, the SnHXGPRT gene sequence was determined and a gene-targeting plasmid was transfected into S. neurona. SnHXGPRT-deficient mutants were selected with 6-TX, and single-cell clones were obtained. These Sn∆HXG parasites were susceptible to MPA and could be complemented using the heterologous T. gondii HXGPRT gene. In summary, S. neurona possesses both purine salvage pathways described in apicomplexans, thus allowing the use of HXGPRT as a positive-negative drug selection marker in this parasite.
2013-01-01
Background Antibiotic/ herbicide resistant marker genes have been proven to be very useful in plant transformation for the initial selection of desired transgenic events. However, presence of these genes in the genetically modified crops may render the crop less acceptable to the consumers. Among several different approaches, the effectiveness of Cre/lox mediated recombination strategy for selectable marker gene (SMG) elimination has previously been demonstrated by different groups in several plants including Brassica. In the present study exploiting Cre/lox mediated recombination strategy, attempt has been made for selectable marker gene elimination from Allium sativum leaf agglutinin (ASAL) expressing Brassica plants with hemipteran insect resistant phenotype. Results Allium sativum leaf agglutinin (ASAL) linked with lox flanked hygromycin resistant (hpt) gene was introduced in mustard. Cre recombinase gene cassette was also integrated in separate event. A Cre/lox mediated recombination using crossing strategy was adopted to remove the hpt gene from the subsequent generation of selected hybrid events. Reciprocal crosses were made between T1ASAL-lox-hpt-lox and cre-bar plants. Marker gene elimination was confirmed in the resulting F1 hybrid progenies by PCR analysis, using hpt, cre and ASAL specific primers followed by Southern hybridization. In marker free plants, expression of ASAL was also confirmed by western blotting and ELISA analysis. Retention of functionality of expressed ASAL was investigated by agglutination assay using rabbit erythrocytes. Expressed ASAL was also found to be thermo-sensitive. In planta insect bioassay on F1 hybrid progenies exhibited detrimental effect on the performance of devastating target pest, Lipaphis erysimi. The F1 hybrid hpt negative, ASAL positive plants were allowed to self- fertilize to obtain F2 progeny plants. In some of these plants cre gene was found to be segregated out of the ASAL gene by genetic segregation yielding completely marker free plants. Conclusions The present study establishes the efficient expression of the newly introduced insect resistant ASAL gene even after Cre/lox mediated recombination resulting in elimination of selectable marker gene. PMID:24144281
Soshi, Takahiro; Nakajima, Heizo; Hagiwara, Hiroko
2016-10-01
Static knowledge about the grammar of a natural language is represented in the cortico-subcortical system. However, the differences in dynamic verbal processing under different cognitive conditions are unclear. To clarify this, we conducted an electrophysiological experiment involving a semantic priming paradigm in which semantically congruent or incongruent word sequences (prime nouns-target verbs) were randomly presented. We examined the event-related brain potentials that occurred in response to congruent and incongruent target words that were preceded by primes with or without grammatical case markers. The two participant groups performed either the shallow (lexical judgment) or deep (direct semantic judgment) semantic tasks. We hypothesized that, irrespective of the case markers, the congruent targets would reduce centro-posterior N400 activities under the deep semantic condition, which induces selective attention to the semantic relatedness of content words. However, the same congruent targets with correct case markers would reduce lateralized negativity under the shallow semantic condition because grammatical case markers are related to automatic structural integration under semantically unattended conditions. We observed that congruent targets (e.g., 'open') that were preceded by primes with congruent case markers (e.g., 'shutter-object case') reduced lateralized negativity under the shallow semantic condition. In contrast, congruent targets, irrespective of case markers, consistently yielded N400 reductions under the deep semantic condition. To summarize, human neural verbal processing differed in response to the same grammatical markers in the same verbal expressions under semantically attended or unattended conditions.
NASA Astrophysics Data System (ADS)
Liu, Chengzhang; Wang, Xia; Xiang, Jianhai; Li, Fuhua
2012-09-01
Pacific white shrimp has become a major aquaculture and fishery species worldwide. Although a large scale EST resource has been publicly available since 2008, the data have not yet been widely used for SNP discovery or transcriptome-wide assessment of selective pressure. In this study, a set of 155 411 expressed sequence tags (ESTs) from the NCBI database were computationally analyzed and 17 225 single nucleotide polymorphisms (SNPs) were predicted, including 9 546 transitions, 5 124 transversions and 2 481 indels. Among the 7 298 SNP substitutions located in functionally annotated contigs, 58.4% (4 262) are non-synonymous SNPs capable of introducing amino acid mutations. Two hundred and fifty nonsynonymous SNPs in genes associated with economic traits have been identified as candidates for markers in selective breeding. Diversity estimates among the synonymous nucleotides were on average 3.49 times greater than those in non-synonymous, suggesting negative selection. Distribution of non-synonymous to synonymous substitutions (Ka/Ks) ratio ranges from 0 to 4.01, (average 0.42, median 0.26), suggesting that the majority of the affected genes are under purifying selection. Enrichment analysis identified multiple gene ontology categories under positive or negative selection. Categories involved in innate immune response and male gamete generation are rich in positively selected genes, which is similar to reports in Drosophila and primates. This work is the first transcriptome-wide assessment of selective pressure in a Penaeid shrimp species. The functionally annotated SNPs provide a valuable resource of potential molecular markers for selective breeding.
USDA-ARS?s Scientific Manuscript database
Agrobacterium overgrowth is a common problem in Agrobacterium-mediated plant transformation. To suppress the Agrobacterium overgrowth, various antibiotics have been used during plant tissue culture steps. The antibiotics are expensive and may adversely affect plant cell differentiation and reduce ...
Chen, Zhuo; Evans, W. Howard; Pflugfelder, Stephen C.; Li, De-Quan
2010-01-01
This study evaluated whether the gap junction protein connexin (Cx) 43 could serve as a negative cell surface marker for human corneal epithelial stem cells. Cx43 expression was evaluated in corneo-limbal tissue and primary limbal epithelial cultures. Immunofluorescent staining and laser scanning confocal microscopy showed that Cx43 was strongly expressed in the corneal and limbal suprabasal epithelial cells, but the basal cells of the limbal epithelium were negative. Cx43 antibody stained mainly large cells but not small cells in primary limbal epithelial cultures. As determined by semiquantitative reverse transcription polymerase chain reaction (PCR) and real-time PCR, Cx43 mRNA was more abundant in the corneal than limbal epithelia, and it was expressed in higher levels in mature limbal epithelial cultures. Using GAP11, a rabbit polyclonal antibody against the Cx32 extracellular loop 2 (151–187), a sequence that is highly homologous in Cx43, the Cx43dim and Cx43bright cells were selected from primary limbal epithelial cultures by fluorescence-activated cell sorting and were evaluated for stem cell properties. These Cx43dim and Cx43bright cells were confirmed by their expression levels of Cx43 protein and mRNA. The Cx43dim cells were found to contain higher percentages of slow-cycling bromodeoxyuridine (BrdU)-label retaining cells and the cells that were positive for stem cell-associated markers p63, ABCG2, and integrin β1 and negative for differentiation markers K3 and involucrin. The Cx43dim cells possessed a greater proliferative potential than Cx43bright cells and nonfractionated cells as evaluated by BrdU incorporation, colony-forming efficiency, and growth capacity. Our findings suggest that human limbal basal cells do not express connexin 43, which could serve as a negative cell surface marker for the stem cell-containing population of human limbal epithelial cells. PMID:16424398
Characterization of novel biomarkers in selecting for subtype specific medulloblastoma phenotypes.
Liang, Lisa; Aiken, Christopher; McClelland, Robyn; Morrison, Ludivine Coudière; Tatari, Nazanin; Remke, Marc; Ramaswamy, Vijay; Issaivanan, Magimairajan; Ryken, Timothy; Del Bigio, Marc R; Taylor, Michael D; Werbowetski-Ogilvie, Tamra E
2015-11-17
Major research efforts have focused on defining cell surface marker profiles for characterization and selection of brain tumor stem/progenitor cells. Medulloblastoma is the most common primary malignant pediatric brain cancer and consists of 4 molecular subgroups: WNT, SHH, Group 3 and Group 4. Given the heterogeneity within and between medulloblastoma variants, surface marker profiles may be subtype-specific. Here, we employed a high throughput flow cytometry screen to identify differentially expressed cell surface markers in self-renewing vs. non-self-renewing SHH medulloblastoma cells. The top 25 markers were reduced to 4, CD271/p75NTR/NGFR, CD106/VCAM1, EGFR and CD171/NCAM-L1, by evaluating transcript levels in SHH tumors relative to samples representing the other variants. However, only CD271/p75NTR/NGFR and CD171/NCAM-L1 maintain differential expression between variants at the protein level. Functional characterization of CD271, a low affinity neurotrophin receptor, in cell lines and primary cultures suggested that CD271 selects for lower self-renewing progenitors or stem cells. Moreover, CD271 levels were negatively correlated with expression of SHH pathway genes. Our study reveals a novel role for CD271 in SHH medulloblastoma and suggests that targeting CD271 pathways could lead to the design of more selective therapies that lessen the broad impact of current treatments on developing nervous systems.
Miah, Gous; Rafii, Mohd Y; Ismail, Mohd R; Puteh, Adam B; Rahim, Harun A; Latif, Mohammad A
2017-07-01
The rice cultivar MR219 is famous for its better yield and long and fine grain quality; however, it is susceptible to blast disease. The main objective of this study was to introgress blast resistance genes into MR219 through marker-assisted selection (MAS). The rice cultivar MR219 was used as the recurrent parent, and Pongsu Seribu 1 was used as the donor. Marker-assisted foreground selection was performed using RM6836 and RM8225 to identify plants possessing blast resistance genes. Seventy microsatellite markers were used to estimate recurrent parent genome (RPG) recovery. Our analysis led to the development of 13 improved blast resistant lines with Piz, Pi2 and Pi9 broad-spectrum blast resistance genes and an MR219 genetic background. The RPG recovery of the selected improved lines was up to 97.70% with an average value of 95.98%. Selected improved lines showed a resistance response against the most virulent blast pathogen pathotype, P7.2. The selected improved lines did not express any negative effect on agronomic traits in comparison with MR219. The research findings of this study will be a conducive approach for the application of different molecular techniques that may result in accelerating the development of new disease-resistant rice varieties, which in turn will match rising demand and food security worldwide. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Takahashi, Hiro; Nakayama, Robert; Hayashi, Shuhei; Nemoto, Takeshi; Murase, Yasuyuki; Nomura, Koji; Takahashi, Teruyoshi; Kubo, Kenji; Marui, Shigetaka; Yasuhara, Koji; Nakamura, Tetsuro; Sueo, Takuya; Takahashi, Anna; Tsutsumiuchi, Kaname; Ohta, Tsutomu; Kawai, Akira; Sugita, Shintaro; Yamamoto, Shinjiro; Kobayashi, Takeshi; Honda, Hiroyuki; Yoshida, Teruhiko; Hasegawa, Tadashi
2013-01-01
The diagnosis and treatment of soft tissue sarcomas (STSs) has been particularly difficult, because STSs are a group of highly heterogeneous tumors in terms of histopathology, histological grade, and primary site. Recent advances in genome technologies have provided an excellent opportunity to determine the complete biological characteristics of neoplastic tissues, resulting in improved diagnosis, treatment selection, and investigation of therapeutic targets. We had previously developed a novel bioinformatics method for marker gene selection and applied this method to gene expression data from STS patients. This previous analysis revealed that the extracted gene combination of macrophage migration inhibitory factor (MIF) and stearoyl-CoA desaturase 1 (SCD1) is an effective diagnostic marker to discriminate between subtypes of STSs with highly different outcomes. In the present study, we hypothesize that the combination of MIF and SCD1 is also a prognostic marker for the overall outcome of STSs. To prove this hypothesis, we first analyzed microarray data from 88 STS patients and their outcomes. Our results show that the survival rates for MIF- and SCD1-positive groups were lower than those for negative groups, and the p values of the log-rank test are 0.0146 and 0.00606, respectively. In addition, survival rates are more significantly different (p = 0.000116) between groups that are double-positive and double-negative for MIF and SCD1. Furthermore, in vitro cell growth inhibition experiments by MIF and SCD1 inhibitors support the hypothesis. These results suggest that the gene set is useful as a prognostic marker associated with tumor progression. PMID:24167613
USDA-ARS?s Scientific Manuscript database
Verticillium wilt (VW), caused primarily by soil-borne fungi Verticillium dahliae Kleb and V. albo-atrum Reinke and Berthold is characterized by unilateral wilting of leaves, chlorosis, and premature senescence. VW is mainly controlled by fumigating fields with metam sodium, which has negative econo...
Płotek, Włodzimierz; Pielok, Joanna; Cybulski, Marcin; Samborska, Regina
2015-01-01
Background The aim of this study was to describe positive and negative emotions in patients undergoing coronary artery bypass graft (CABG) surgeries with extracorporeal circulation and the correlations between emotions and basic indicators of the inflammatory condition: C-reactive protein (CRP) concentration, body temperature, and leukocyte count. Material/Methods Standardized tools were used to select 52 patients (aged 47–63 years, 6 women – 11.5% and 46 men – 88.5%) without dementia or depression. The Positive and Negative Affect Schedule (PANAS) was used to examine positive affect (PA) and negative affect (NA) and the State-Trait Anxiety Inventory (STAI X1 and X2) was used to examine the anxiety level. The patients underwent CABG surgery according to a common anesthesia protocol and for 5 consecutive days they were observed in the ward, where selected indicators of the inflammatory condition were monitored. Results A detailed description of the results of examinations of emotions was presented. The patients with low PA-trait level, high NA-trait level, and high anxiety-trait level (STAI X2) exhibited statistically significantly higher body temperatures than the other patients in the postoperative period. The patients with high NA-trait and anxiety-state levels (STAI X1) had statistically significantly lower CRP levels in the postoperative period than the patients with low NA-trait and anxiety-state levels (STAI X1). Conclusions Patients undergoing CABG operations express both positive and negative affects. The changes in the inflammatory markers are expressed mostly by CRP concentration. There exist relationships between the result of tests assessing emotions and the markers of the inflammatory condition. PMID:25573296
Sengupta, Subhadipa; Chakraborti, Dipankar; Mondal, Hossain A; Das, Sampa
2010-03-01
Rice, the major food crop of world is severely affected by homopteran sucking pests. We introduced coding sequence of Allium sativum leaf agglutinin, ASAL, in rice cultivar IR64 to develop sustainable resistance against sap-sucking planthoppers as well as eliminated the selectable antibiotic-resistant marker gene hygromycin phosphotransferase (hpt) exploiting cre/lox site-specific recombination system. An expression vector was constructed containing the coding sequence of ASAL, a potent controlling agent against green leafhoppers (GLH, Nephotettix virescens) and brown planthopper (BPH, Nilaparvata lugens). The selectable marker (hpt) gene cassette was cloned within two lox sites of the same vector. Alongside, another vector was developed with chimeric cre recombinase gene cassette. Reciprocal crosses were performed between three single-copy T(0) plants with ASAL- lox-hpt-lox T-DNA and three single-copy T(0) plants with cre-bar T-DNA. Marker gene excisions were detected in T(1) hybrids through hygromycin sensitivity assay. Molecular analysis of T(1) plants exhibited 27.4% recombination efficiency. T(2) progenies of L03C04(1) hybrid parent showed 25% cre negative ASAL-expressing plants. Northern blot, western blot and ELISA showed significant level of ASAL expression in five marker-free T(2) progeny plants. In planta bioassay of GLH and BPH performed on these T(2) progenies exhibited radical reduction in survivability and fecundity compared with the untransformed control plants.
Nishimaki, Takahiro; Ibi, Takayuki; Siqintuya; Kobayashi, Naohiko; Matsuhashi, Tamako; Akiyama, Takayuki; Yoshida, Emi; Imai, Kazumi; Matsui, Mayu; Uemura, Keiichi; Eto, Hisayoshi; Watanabe, Naoto; Fujita, Tatsuo; Saito, Yosuke; Komatsu, Tomohiko; Hoshiba, Hiroshi; Mannen, Hideyuki; Sasazaki, Shinji; Kunieda, Tetsuo
2016-04-01
Marker-assisted selection (MAS) is expected to accelerate the genetic improvement of Japanese Black cattle. However, verification of the effects of the genes for MAS in different subpopulations is required prior to the application of MAS. In this study, we investigated the allelic frequencies and genotypic effects for carcass traits of six genes, which can be used in MAS, in eight local subpopulations. These genes are SCD, FASN and SREBP1, which are associated with the fatty acid composition of meat, and NCAPG, MC1R and F11, which are associated with carcass weight, coat color and blood coagulation abnormality, respectively. The frequencies of desirable alleles of SCD and FASN were relatively high and that of NCAPG was relatively low, and NCAPG was significantly associated with several carcass traits, including carcass weight. The proportions of genotypic variance explained by NCAPG to phenotypic variance were 4.83 for carcass weight. We thus confirmed that NCAPG is a useful marker for selection of carcass traits in these subpopulations. In addition, we found that the desirable alleles of six genes showed no negative effects on carcass traits. Therefore, selection using these genes to improve target traits should not have negative impacts on carcass traits. © 2015 Japanese Society of Animal Science.
USDA-ARS?s Scientific Manuscript database
Some lettuce cultivars are highly sensitive to triforine, an inhibitor of sterol biosynthesis found in some commercial systemic fungicides. First symptoms of a sensitive reaction are usually observed within 24 to 48 hours after treatment and include severe wilting, necrosis and rapid plant death. We...
Antibiotic Combinations That Enable One-Step, Targeted Mutagenesis of Chromosomal Genes.
Lee, Wonsik; Do, Truc; Zhang, Ge; Kahne, Daniel; Meredith, Timothy C; Walker, Suzanne
2018-06-08
Targeted modification of bacterial chromosomes is necessary to understand new drug targets, investigate virulence factors, elucidate cell physiology, and validate results of -omics-based approaches. For some bacteria, reverse genetics remains a major bottleneck to progress in research. Here, we describe a compound-centric strategy that combines new negative selection markers with known positive selection markers to achieve simple, efficient one-step genome engineering of bacterial chromosomes. The method was inspired by the observation that certain nonessential metabolic pathways contain essential late steps, suggesting that antibiotics targeting a late step can be used to select for the absence of genes that control flux into the pathway. Guided by this hypothesis, we have identified antibiotic/counterselectable markers to accelerate reverse engineering of two increasingly antibiotic-resistant pathogens, Staphylococcus aureus and Acinetobacter baumannii. For S. aureus, we used wall teichoic acid biosynthesis inhibitors to select for the absence of tarO and for A. baumannii, we used colistin to select for the absence of lpxC. We have obtained desired gene deletions, gene fusions, and promoter swaps in a single plating step with perfect efficiency. Our method can also be adapted to generate markerless deletions of genes using FLP recombinase. The tools described here will accelerate research on two important pathogens, and the concept we outline can be readily adapted to any organism for which a suitable target pathway can be identified.
Parkinson's disease biomarkers: perspective from the NINDS Parkinson's Disease Biomarkers Program
Gwinn, Katrina; David, Karen K; Swanson-Fischer, Christine; Albin, Roger; Hillaire-Clarke, Coryse St; Sieber, Beth-Anne; Lungu, Codrin; Bowman, F DuBois; Alcalay, Roy N; Babcock, Debra; Dawson, Ted M; Dewey, Richard B; Foroud, Tatiana; German, Dwight; Huang, Xuemei; Petyuk, Vlad; Potashkin, Judith A; Saunders-Pullman, Rachel; Sutherland, Margaret; Walt, David R; West, Andrew B; Zhang, Jing; Chen-Plotkin, Alice; Scherzer, Clemens R; Vaillancourt, David E; Rosenthal, Liana S
2017-01-01
Biomarkers for Parkinson's disease (PD) diagnosis, prognostication and clinical trial cohort selection are an urgent need. While many promising markers have been discovered through the National Institute of Neurological Disorders and Stroke Parkinson's Disease Biomarker Program (PDBP) and other mechanisms, no single PD marker or set of markers are ready for clinical use. Here we discuss the current state of biomarker discovery for platforms relevant to PDBP. We discuss the role of the PDBP in PD biomarker identification and present guidelines to facilitate their development. These guidelines include: harmonizing procedures for biofluid acquisition and clinical assessments, replication of the most promising biomarkers, support and encouragement of publications that report negative findings, longitudinal follow-up of current cohorts including the PDBP, testing of wearable technologies to capture readouts between study visits and development of recently diagnosed (de novo) cohorts to foster identification of the earliest markers of disease onset. PMID:28644039
Foolad, Mahsa; Ong, Say Leong; Hu, Jiangyong
2015-11-01
Pharmaceutical and personal care products (PPCPs) and artificial sweeteners (ASs) are emerging organic contaminants (EOCs) in the aquatic environment. The presence of PPCPs and ASs in water bodies has an ecologic potential risk and health concern. Therefore, it is needed to detect the pollution sources by understanding the transport behavior of sewage molecular markers in a subsurface area. The aim of this study was to evaluate transport of nine selected molecular markers through saturated soil column experiments. The selected sewage molecular markers in this study were six PPCPs including acetaminophen (ACT), carbamazepine (CBZ), caffeine (CF), crotamiton (CTMT), diethyltoluamide (DEET), salicylic acid (SA) and three ASs including acesulfame (ACF), cyclamate (CYC), and saccharine (SAC). Results confirmed that ACF, CBZ, CTMT, CYC and SAC were suitable to be used as sewage molecular markers since they were almost stable against sorption and biodegradation process during soil column experiments. In contrast, transport of ACT, CF and DEET were limited by both sorption and biodegradation processes and 100% removal efficiency was achieved in the biotic column. Moreover, in this study the effect of different acetate concentration (0-100mg/L) as an easily biodegradable primary substrate on a removal of PPCPs and ASs was also studied. Results showed a negative correlation (r(2)>0.75) between the removal of some selected sewage chemical markers including ACF, CF, ACT, CYC, SAC and acetate concentration. CTMT also decreased with the addition of acetate, but increasing acetate concentration did not affect on its removal. CBZ and DEET removal were not dependent on the presence of acetate. Copyright © 2015 Elsevier Ltd. All rights reserved.
Son, Kiho; Mukherjee, Manali; McIntyre, Brendan A S; Eguez, Jose C; Radford, Katherine; LaVigne, Nicola; Ethier, Caroline; Davoine, Francis; Janssen, Luke; Lacy, Paige; Nair, Parameswaran
2017-10-01
Clinically relevant and reliable reports derived from in vitro research are dependent on the choice of cell isolation protocols adopted between different laboratories. Peripheral blood eosinophils are conventionally isolated using density-gradient centrifugation followed by immunomagnetic selection (positive/negative) while neutrophils follow a more simplified dextran-sedimentation methodology. With the increasing sophistication of molecular techniques, methods are now available that promise protocols with reduced user-manipulations, improved efficiency, and better yield without compromising the purity of enriched cell populations. These recent techniques utilize immunomagnetic particles with multiple specificities against differential cell surface markers to negatively select non-target cells from whole blood, greatly reducing the cost/time taken to isolate granulocytes. Herein, we compare the yield efficiencies, purity and baseline activation states of eosinophils/neutrophils isolated using one of these newer protocols that use immunomagnetic beads (MACSxpress isolation) vs. the standard isolation procedures. The study shows that the MACSxpress method consistently allowed higher yields per mL of peripheral blood compared to conventional methods (P<0.001, n=8, Wilcoxon paired test), with high isolation purities for both eosinophils (95.0±1.7%) and neutrophils (94.2±10.1%) assessed by two methods: Wright's staining and flow cytometry. In addition, enumeration of CD63 + (marker for eosinophil activation) and CD66b + (marker for neutrophil activation) cells within freshly isolated granulocytes, respectively, confirmed that conventional protocols using density-gradient centrifugation caused cellular activation of the granulocytes at baseline compared to the MACSxpress method. In conclusion, MACSxpress isolation kits were found to be superior to conventional techniques for consistent purifications of eosinophils and neutrophils that were suitable for activation assays involving degranulation markers. Copyright © 2017 Elsevier B.V. All rights reserved.
Zlobec, Inti; Bihl, Michel; Foerster, Anja; Rufle, Alex; Lugli, Alessandro
2011-11-01
CpG island methylator phenotype (CIMP) is being investigated for its role in the molecular and prognostic classification of colorectal cancer patients but is also emerging as a factor with the potential to influence clinical decision-making. We report a comprehensive analysis of clinico-pathological and molecular features (KRAS, BRAF and microsatellite instability, MSI) as well as of selected tumour- and host-related protein markers characterizing CIMP-high (CIMP-H), -low, and -negative colorectal cancers. Immunohistochemical analysis for 48 protein markers and molecular analysis of CIMP (CIMP-H: ≥ 4/5 methylated genes), MSI (MSI-H: ≥ 2 instable genes), KRAS, and BRAF were performed on 337 colorectal cancers. Simple and multiple regression analysis and receiver operating characteristic (ROC) curve analysis were performed. CIMP-H was found in 24 cases (7.1%) and linked (p < 0.0001) to more proximal tumour location, BRAF mutation, MSI-H, MGMT methylation (p = 0.022), advanced pT classification (p = 0.03), mucinous histology (p = 0.069), and less frequent KRAS mutation (p = 0.067) compared to CIMP-low or -negative cases. Of the 48 protein markers, decreased levels of RKIP (p = 0.0056), EphB2 (p = 0.0045), CK20 (p = 0.002), and Cdx2 (p < 0.0001) and increased numbers of CD8+ intra-epithelial lymphocytes (p < 0.0001) were related to CIMP-H, independently of MSI status. In addition to the expected clinico-pathological and molecular associations, CIMP-H colorectal cancers are characterized by a loss of protein markers associated with differentiation, and metastasis suppression, and have increased CD8+ T-lymphocytes regardless of MSI status. In particular, Cdx2 loss seems to strongly predict CIMP-H in both microsatellite-stable (MSS) and MSI-H colorectal cancers. Cdx2 is proposed as a surrogate marker for CIMP-H. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
An efficient platform for genetic selection and screening of gene switches in Escherichia coli
Muranaka, Norihito; Sharma, Vandana; Nomura, Yoko; Yokobayashi, Yohei
2009-01-01
Engineered gene switches and circuits that can sense various biochemical and physical signals, perform computation, and produce predictable outputs are expected to greatly advance our ability to program complex cellular behaviors. However, rational design of gene switches and circuits that function in living cells is challenging due to the complex intracellular milieu. Consequently, most successful designs of gene switches and circuits have relied, to some extent, on high-throughput screening and/or selection from combinatorial libraries of gene switch and circuit variants. In this study, we describe a generic and efficient platform for selection and screening of gene switches and circuits in Escherichia coli from large libraries. The single-gene dual selection marker tetA was translationally fused to green fluorescent protein (gfpuv) via a flexible peptide linker and used as a dual selection and screening marker for laboratory evolution of gene switches. Single-cycle (sequential positive and negative selections) enrichment efficiencies of >7000 were observed in mock selections of model libraries containing functional riboswitches in liquid culture. The technique was applied to optimize various parameters affecting the selection outcome, and to isolate novel thiamine pyrophosphate riboswitches from a complex library. Artificial riboswitches with excellent characteristics were isolated that exhibit up to 58-fold activation as measured by fluorescent reporter gene assay. PMID:19190095
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lim, Tze Yee
Purpose: For postimplant dosimetric assessment, computed tomography (CT) is commonly used to identify prostate brachytherapy seeds, at the expense of accurate anatomical contouring. Magnetic resonance imaging (MRI) is superior to CT for anatomical delineation, but identification of the negative-contrast seeds is challenging. Positive-contrast MRI markers were proposed to replace spacers to assist seed localization on MRI images. Visualization of these markers under varying scan parameters was investigated. Methods: To simulate a clinical scenario, a prostate phantom was implanted with 66 markers and 86 seeds, and imaged on a 3.0T MRI scanner using a 3D fast radiofrequency-spoiled gradient recalled echo acquisitionmore » with various combinations of scan parameters. Scan parameters, including flip angle, number of excitations, bandwidth, field-of-view, slice thickness, and encoding steps were systematically varied to study their effects on signal, noise, scan time, image resolution, and artifacts. Results: The effects of pulse sequence parameter selection on the marker signal strength and image noise were characterized. The authors also examined the tradeoff between signal-to-noise ratio, scan time, and image artifacts, such as the wraparound artifact, susceptibility artifact, chemical shift artifact, and partial volume averaging artifact. Given reasonable scan time and managable artifacts, the authors recommended scan parameter combinations that can provide robust visualization of the MRI markers. Conclusions: The recommended MRI pulse sequence protocol allows for consistent visualization of the markers to assist seed localization, potentially enabling MRI-only prostate postimplant dosimetry.« less
Atagi, Y; Onogi, A; Kinukawa, M; Ogino, A; Kurogi, K; Uchiyama, K; Yasumori, T; Adachi, K; Togashi, K; Iwata, H
2017-05-01
The semen production traits of bulls from 2 major cattle breeds in Japan, Holstein and Japanese Black, were analyzed comprehensively using genome-wide markers. Weaker genetic correlations were observed between the 2 age groups (1 to 3 yr old and 4 to 6 yr old) regarding semen volume and sperm motility compared with those observed for sperm number and motility after freeze-thawing. The preselection of collected semen for freezing had a limited effect. Given the increasing importance of bull proofs at a young age because of genomic selection and the results from preliminary studies, we used a multiple-trait model that included motility after freeze-thawing with records collected at young ages. Based on variations in contemporary group effects, accounting for both seasonal and management factors, Holstein bulls may be more sensitive than Japanese Black bulls to seasonal environmental variations; however, the seasonal variations of contemporary group effects were smaller than those of overall contemporary group effects. The improvement of motilities, recorded immediately after collection and freeze-thawing, was observed in recent years; thus, good management and better freeze-thawing protocol may alleviate seasonal phenotypic differences. The detrimental effects of inbreeding were observed in all traits of both breeds; accordingly, the selection of candidate bulls with high inbreeding coefficients should be avoided per general recommendations. Semen production traits have never been considered for bull selection. However, negative genetic trends were observed. The magnitudes of the estimated h were comparable to those of other economically important traits. A single-step genomic BLUP will provide more accurate predictions of breeding values compared with BLUP; thus, marker genotype information is useful for estimating the genetic merits of bulls for semen production traits. The selection of these traits would improve sperm viability, a component related to breeding success, and alleviate negative genetic trends.
Behnke, Michael S; Khan, Asis; Sibley, L David
2015-02-01
Quantitative trait locus (QTL) mapping studies have been integral in identifying and understanding virulence mechanisms in the parasite Toxoplasma gondii. In this study, we interrogated a different phenotype by mapping sinefungin (SNF) resistance in the genetic cross between type 2 ME49-FUDR(r) and type 10 VAND-SNF(r). The genetic map of this cross was generated by whole-genome sequencing of the progeny and subsequent identification of single nucleotide polymorphisms (SNPs) inherited from the parents. Based on this high-density genetic map, we were able to pinpoint the sinefungin resistance phenotype to one significant locus on chromosome IX. Within this locus, a single nonsynonymous SNP (nsSNP) resulting in an early stop codon in the TGVAND_290860 gene was identified, occurring only in the sinefungin-resistant progeny. Using CRISPR/CAS9, we were able to confirm that targeted disruption of TGVAND_290860 renders parasites sinefungin resistant. Because disruption of the SNR1 gene confers resistance, we also show that it can be used as a negative selectable marker to insert either a positive drug selection cassette or a heterologous reporter. These data demonstrate the power of combining classical genetic mapping, whole-genome sequencing, and CRISPR-mediated gene disruption for combined forward and reverse genetic strategies in T. gondii. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Liang, Liqin; Li, Jianqiang; Cheng, Lin; Ling, Jian; Luo, Zhongqin; Bai, Miao; Xie, Bingyan
2014-11-01
The Fusarium oxysporum species complex consists of fungal pathogens that cause serial vascular wilt disease on more than 100 cultivated species throughout the world. Gene function analysis is rapidly becoming more and more important as the whole-genome sequences of various F. oxysporum strains are being completed. Gene-disruption techniques are a common molecular tool for studying gene function, yet are often a limiting step in gene function identification. In this study we have developed a F. oxysporum high-efficiency gene-disruption strategy based on split-marker homologous recombination cassettes with dual selection and electroporation transformation. The method was efficiently used to delete three RNA-dependent RNA polymerase (RdRP) genes. The gene-disruption cassettes of three genes can be constructed simultaneously within a short time using this technique. The optimal condition for electroporation is 10μF capacitance, 300Ω resistance, 4kV/cm field strength, with 1μg of DNA (gene-disruption cassettes). Under these optimal conditions, we were able to obtain 95 transformants per μg DNA. And after positive-negative selection, the transformants were efficiently screened by PCR, screening efficiency averaged 85%: 90% (RdRP1), 85% (RdRP2) and 77% (RdRP3). This gene-disruption strategy should pave the way for high throughout genetic analysis in F. oxysporum. Copyright © 2014 Elsevier GmbH. All rights reserved.
Use of luminescent gunshot residues markers in forensic context.
Weber, I T; Melo, A J G; Lucena, M A M; Consoli, E F; Rodrigues, M O; de Sá, G F; Maldaner, A O; Talhavini, M; Alves, S
2014-11-01
Chemical evaluation of gunshot residues (GSR) produced by non-toxic lead-free ammunition (NTA) has been a challenge to forensic analyses. Our group developed some luminescent markers specific to the detection of GSR. Here, we evaluated the performance of selected markers in experiments that mimic forensic context and/or routines in which luminescent characteristics would be very useful. We evaluated the influence of markers' addition on the bullet's speed, the rate of shot failure (i.e., when the cartridge case is not fully ejected and/or a new ammunition is not automatically replaced in the gun chamber) as a function of marker percentage, the possibility of collecting luminescent gunshot residue (LGSR) in unconventional locations (e.g. the shooters' nostrils), the LGSR lifetime after hand washing, the transfer of LGSR to objects handled by the shooter, and the dispersion of LGSR at the crime scene and on simulated victims. It was observed that high amounts of marker (10 wt%) cause high rates of failure on pistols, as well as a substantial decrease in bullet speed. However, the use of 2 wt% of marker minimizes these effects and allows LGSR detection, collection and analysis. Moreover, in all conditions tested, markers showed high performance and provided important information for forensic analyses. For instance, the LGSR particles were found on the floor, ranging from 0 to 9.4 m away from the shooter, on the door panel and seats after a car shooting experiment, and were found easily on a pig leg used to simulate a victim. When a selective tagging was done, it was possible to obtain positive or negative correlation between the victim and shooter. Additionally LGSR possesses a fairly long lifetime (9 h) and good resistance to hand washing (up to 16 washes). Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Liu, Y; Yan, L; Li, Z; Huang, W-F; Pokhrel, S; Liu, X; Su, S
2016-06-01
Chalkbrood is a disease affecting honey bees that seriously impairs brood growth and productivity of diseased colonies. Although honey bees can develop chalkbrood resistance naturally, the details underlying the mechanisms of resistance are not fully understood, and no easy method is currently available for selecting and breeding resistant bees. Finding the genes involved in the development of resistance and identifying single nucleotide polymorphisms (SNPs) that can be used as molecular markers of resistance is therefore a high priority. We conducted genome resequencing to compare resistant (Res) and susceptible (Sus) larvae that were selected following in vitro chalkbrood inoculation. Twelve genomic libraries, including 14.4 Gb of sequence data, were analysed using SNP-finding algorithms. Unique SNPs derived from chromosomes 2 and 11 were analysed in this study. SNPs from resistant individuals were confirmed by PCR and Sanger sequencing using in vitro reared larvae and resistant colonies. We found strong support for an association between the C allele at SNP C2587245T and chalkbrood resistance. SNP C2587245T may be useful as a genetic marker for the selection of chalkbrood resistance and high royal jelly production honey bee lines, thereby helping to minimize the negative effects of chalkbrood on managed honey bees. © 2016 The Royal Entomological Society.
Pandeya, Devendra; Campbell, LeAnne M; Nunes, Eugenia; Lopez-Arredondo, Damar L; Janga, Madhusudhana R; Herrera-Estrella, Luis; Rathore, Keerti S
2017-12-01
This report demonstrates the usefulness of ptxD/phosphite as a selection system that not only provides a highly efficient and simple means to generate transgenic cotton plants, but also helps address many of the concerns related to the use of antibiotic and herbicide resistance genes in the production of transgenic crops. Two of the most popular dominant selectable marker systems for plant transformation are based on either antibiotic or herbicide resistance genes. Due to concerns regarding their safety and in order to stack multiple traits in a single plant, there is a need for alternative selectable marker genes. The ptxD gene, derived from Pseudomonas stutzeri WM88, that confers to cells the ability to convert phosphite (Phi) into orthophosphate (Pi) offers an alternative selectable marker gene as demonstrated for tobacco and maize. Here, we show that the ptxD gene in combination with a protocol based on selection medium containing Phi, as the sole source of phosphorus (P), can serve as an effective and efficient system to select for transformed cells and generate transgenic cotton plants. Fluorescence microscopy examination of the cultures under selection and molecular analyses on the regenerated plants demonstrate the efficacy of the system in recovering cotton transformants following Agrobacterium-mediated transformation. Under the ptxD/Phi selection, an average of 3.43 transgenic events per 100 infected explants were recovered as opposed to only 0.41% recovery when bar/phosphinothricin (PPT) selection was used. The event recovery rates for nptII/kanamycin and hpt/hygromycin systems were 2.88 and 2.47%, respectively. Molecular analysis on regenerated events showed a selection efficiency of ~ 97% under the ptxD/Phi system. Thus, ptxD/Phi has proven to be a very efficient, positive selection system for the generation of transgenic cotton plants with equal or higher transformation efficiencies compared to the commonly used, negative selection systems.
Sliwa, Ewa; Adaszek, Łukasz; Tatara, Marcin; Dobrowolski, Piotr
2010-01-01
The aim of this study was to investigate short-term 4 and 14 weeks after fundectomy) and long-term (at the age of 8 months) postoperative effects of 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate on selected serum biochemical markers in fundectomized pigs. Experimental fundectomy was performed in 30 castrated male pigs of the Puławska breed who received placebo or 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate up to the age of 8 months. Plasma amino acid concentrations and selected blood parameters were analyzed. Main vital organs were weighed. Our study showed that the supplementations with alpha-ketoglutarate and/or 3-hydroxy-3-methylbutyrate to fundectomized pigs significantly prevented the reduction of stomach, liver and spleen weights. However, results of this study, either positive or negative, cannot categorically establish a beneficial effect of AKG and HMB nutritional support after fundectomy in pigs.
Saito, Shinta; Ura, Kiyoe; Kodama, Miho; Adachi, Noritaka
2015-06-30
Targeted gene modification by homologous recombination provides a powerful tool for studying gene function in cells and animals. In higher eukaryotes, non-homologous integration of targeting vectors occurs several orders of magnitude more frequently than does targeted integration, making the gene-targeting technology highly inefficient. For this reason, negative-selection strategies have been employed to reduce the number of drug-resistant clones associated with non-homologous vector integration, particularly when artificial nucleases to introduce a DNA break at the target site are unavailable or undesirable. As such, an exon-trap strategy using a promoterless drug-resistance marker gene provides an effective way to counterselect non-homologous integrants. However, constructing exon-trapping targeting vectors has been a time-consuming and complicated process. By virtue of highly efficient att-mediated recombination, we successfully developed a simple and rapid method to construct plasmid-based vectors that allow for exon-trapping gene targeting. These exon-trap vectors were useful in obtaining correctly targeted clones in mouse embryonic stem cells and human HT1080 cells. Most importantly, with the use of a conditionally cytotoxic gene, we further developed a novel strategy for negative selection, thereby enhancing the efficiency of counterselection for non-homologous integration of exon-trap vectors. Our methods will greatly facilitate exon-trapping gene-targeting technologies in mammalian cells, particularly when combined with the novel negative selection strategy.
Cloning-Independent and Counterselectable Markerless Mutagenesis System in Streptococcus mutans▿
Xie, Zhoujie; Okinaga, Toshinori; Qi, Fengxia; Zhang, Zhijun; Merritt, Justin
2011-01-01
Insertion duplication mutagenesis and allelic replacement mutagenesis are among the most commonly utilized approaches for targeted mutagenesis in bacteria. However, both techniques are limited by a variety of factors that can complicate mutant phenotypic studies. To circumvent these limitations, multiple markerless mutagenesis techniques have been developed that utilize either temperature-sensitive plasmids or counterselectable suicide vectors containing both positive- and negative-selection markers. For many species, these techniques are not especially useful due to difficulties of cloning with Escherichia coli and/or a lack of functional negative-selection markers. In this study, we describe the development of a novel approach for the creation of markerless mutations. This system employs a cloning-independent methodology and should be easily adaptable to a wide array of Gram-positive and Gram-negative bacterial species. The entire process of creating both the counterselection cassette and mutation constructs can be completed using overlapping PCR protocols, which allows extremely quick assembly and eliminates the requirement for either temperature-sensitive replicons or suicide vectors. As a proof of principle, we used Streptococcus mutans reference strain UA159 to create markerless in-frame deletions of 3 separate bacteriocin genes as well as triple mutants containing all 3 deletions. Using a panel of 5 separate wild-type S. mutans strains, we further demonstrated that the procedure is nearly 100% efficient at generating clones with the desired markerless mutation, which is a considerable improvement in yield compared to existing approaches. PMID:21948849
Nanoparticle-assay marker interaction: effects on nanotoxicity assessment
NASA Astrophysics Data System (ADS)
Zhao, Xinxin; Xiong, Sijing; Huang, Liwen Charlotte; Ng, Kee Woei; Loo, Say Chye Joachim
2015-01-01
Protein-based cytotoxicity assays such as lactate dehydrogenase (LDH) and tumor necrosis factor-alpha (TNF-α) are commonly used in cytotoxic evaluation of nanoparticles (NPs) despite numerous reports on possible interactions with protein markers in these assays that can confound the results obtained. In this study, conventional cytotoxicity assays where assay markers may (LDH and TNF- α) or may not (PicoGreen and WST-8) come into contact with NPs were used to evaluate the cytotoxicity of NPs. The findings revealed selective interactions between negatively charged protein assay markers (LDH and TNF- α) and positively charged ZnO NPs under abiotic conditions. The adsorption and interaction with these protein assay markers were strongly influenced by surface charge, concentration, and specific surface area of the NPs, thereby resulting in less than accurate cytotoxic measurements, as observed from actual cell viability measurements. An improved protocol for LDH assay was, therefore, proposed and validated by eliminating any effects associated with protein-particle interactions. In view of this, additional measures and precautions should be taken when evaluating cytotoxicity of NPs with standard protein-based assays, particularly when they are of opposite charges.
Wang, F; Marchini, A; Kieff, E
1991-01-01
The objective of these experiments was to develop strategies for creation and identification of recombinant mutant Epstein-Barr viruses (EBV). EBV recombinant molecular genetics has been limited to mutations within a short DNA segment deleted from a nontransforming EBV and an underlying strategy which relies on growth transformation of primary B lymphocytes for identification of recombinants. Thus, mutations outside the deletion or mutations which affect transformation cannot be easily recovered. In these experiments we investigated whether a toxic drug resistance gene, guanine phosphoribosyltransferase or hygromycin phosphotransferase, driven by the simian virus 40 promoter can be recombined into the EBV genome and can function to identify B-lymphoma cells infected with recombinant virus. Two different strategies were used to recombine the drug resistance marker into the EBV genome. Both utilized transfection of partially permissive, EBV-infected B95-8 cells and positive selection for cells which had incorporated a functional drug resistance gene. In the first series of experiments, B95-8 clones were screened for transfected DNA that had recombined into the EBV genome. In the second series of experiments, the transfected drug resistance marker was linked to the plasmid and lytic EBV origins so that it was maintained as an episome and could recombine with the B95-8 EBV genome during virus replication. The recombinant EBV from either experiment could be recovered by infection and toxic drug selection of EBV-negative B-lymphoma cells. The EBV genome in these B-lymphoma cells is frequently an episome. Virus genes associated with latent infection of primary B lymphocytes are expressed. Expression of Epstein-Barr virus nuclear antigen 2 (EBNA-2) and the EBNA-3 genes is variable relative to that of EBNA-1, as is characteristic of some naturally infected Burkitt tumor cells. Moreover, the EBV-infected B-lymphoma cells are often partially permissive for early replicative cycle gene expression and virus replication can be induced, in contrast to previously reported in vitro infected B-lymphoma cells. These studies demonstrate that dominant selectable markers can be inserted into the EBV genome, are active in the context of the EBV genome, and can be used to recover recombinant EBV in B-lymphoma cells. This system should be particularly useful for recovering EBV genomes with mutations in essential transforming genes. Images PMID:1848303
Wang, F; Marchini, A; Kieff, E
1991-04-01
The objective of these experiments was to develop strategies for creation and identification of recombinant mutant Epstein-Barr viruses (EBV). EBV recombinant molecular genetics has been limited to mutations within a short DNA segment deleted from a nontransforming EBV and an underlying strategy which relies on growth transformation of primary B lymphocytes for identification of recombinants. Thus, mutations outside the deletion or mutations which affect transformation cannot be easily recovered. In these experiments we investigated whether a toxic drug resistance gene, guanine phosphoribosyltransferase or hygromycin phosphotransferase, driven by the simian virus 40 promoter can be recombined into the EBV genome and can function to identify B-lymphoma cells infected with recombinant virus. Two different strategies were used to recombine the drug resistance marker into the EBV genome. Both utilized transfection of partially permissive, EBV-infected B95-8 cells and positive selection for cells which had incorporated a functional drug resistance gene. In the first series of experiments, B95-8 clones were screened for transfected DNA that had recombined into the EBV genome. In the second series of experiments, the transfected drug resistance marker was linked to the plasmid and lytic EBV origins so that it was maintained as an episome and could recombine with the B95-8 EBV genome during virus replication. The recombinant EBV from either experiment could be recovered by infection and toxic drug selection of EBV-negative B-lymphoma cells. The EBV genome in these B-lymphoma cells is frequently an episome. Virus genes associated with latent infection of primary B lymphocytes are expressed. Expression of Epstein-Barr virus nuclear antigen 2 (EBNA-2) and the EBNA-3 genes is variable relative to that of EBNA-1, as is characteristic of some naturally infected Burkitt tumor cells. Moreover, the EBV-infected B-lymphoma cells are often partially permissive for early replicative cycle gene expression and virus replication can be induced, in contrast to previously reported in vitro infected B-lymphoma cells. These studies demonstrate that dominant selectable markers can be inserted into the EBV genome, are active in the context of the EBV genome, and can be used to recover recombinant EBV in B-lymphoma cells. This system should be particularly useful for recovering EBV genomes with mutations in essential transforming genes.
Simões, G A R; Xavier, M A S; Oliveira, D A; Menezes, E V; Magalhães, S S G; Gandra, J A C D; Xavier, A R E O
2016-06-17
Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for β-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid.
Identification of marker chromosomes in thirteen patients using FISH probing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daniel, A.; Malafiej, P.; Preece, K.
1994-10-15
Fourteen marker chromosomes were studied by FISH (fluorescence in-situ hybridization) in cytogenetic preparations from 13 patients. The derived markers were identified as one isodicentric bisatellited mar(22), one fragment sized r(X), one fragment sized r(Y), one i(18p), small autosomal ring markers in three different patients derived from chromosomes 2, 8, and 8, a marker comprised of 9p and part of 9qh, and 3 bisatellited apparently monocentric markers; one of each from chromosomes 13 or 21, 14 or 22, and 15. Two fragment sized small ring markers in one patient and a small ring marker in another were negative with all twenty-twomore » different probes used. In addition, the small ring marker Y chromosome that was found in a boy with karyotype 46, X, -Y, +mar was negative with both pDXZ1 and pDYZ3. This anomaly of negative results with the battery of centromeric alphoid probes can be explained if one breakpoint for some small ring markers is very near to or within the centromere. The literature was reviewed for Distamycin A/DAPI negative small ring markers that were present as extra chromosomes. There were only single published cases of most small rings but there were three r(8) cases, two r(1) cases, two r(12) cases, and two r(20) cases, uncomplicated by the presence of other chromosome abnormalities. In pooled data, 18/23 (about 80%) were developmentally and/or phenotypically abnormal. Some patients (5/23, about 20%) with small rings were dysmorphic without intellectual handicap. Of 28 such patients with small ring markers (Distamycin/Dapi negative) in pooled data there are 6 (about 20%) with multiple markers mostly derived from different chromosomes. This is a very high figure and would suggest that the ring formation events, although involving different chromosomes, must be related and must be an indicator of the mechanism of origin of this group of markers. 14 refs., 3 figs., 3 tabs.« less
Aydemir, Ömer; Çubukçuoğlu, Zeynep; Erdin, Soner; Taş, Cumhur; Onur, Ece; Berk, Michael
2014-01-01
This study aimed to evaluate the relationship between oxidative stress markers and cognitive functions and domains of psychosocial functioning in bipolar disorder. Oxidative stress markers, cognitive functions, and domains of psychosocial functioning were evaluated in 51 patients with bipolar disorder who were in remission. Correlation analyses between these parameters were calculated with data controlled for duration of illness and number of episodes. There was no statistically significant correlation between oxidative stress markers and cognitive functions. In terms of psychosocial functioning, significant correlations were found between malondialdehyde and sense of stigmatization (r = -0.502); household activities and superoxide dismutase (r = 0.501); participation in social activities and nitric oxide (r = 0.414); hobbies and leisure time activities and total glutathione (r = -0.567), superoxide dismutase (r = 0.667), and neurotrophin 4 (r = 0.450); and taking initiative and self-sufficiency and superoxide dismutase (r = 0.597). There was no correlation between other domains of psychosocial functioning and oxidative stress markers. These results imply that oxidative stress markers do not appear to correlate clearly with cognitive impairment and reduced psychosocial functioning. However, there were some associations between selected oxidative markers and activity-oriented functional markers. This may represent a true negative association, or may be an artifact of oxidative stress being a state rather than a trait marker.
Ogino, Shuji; Kawasaki, Takako; Kirkner, Gregory J; Kraft, Peter; Loda, Massimo; Fuchs, Charles S
2007-07-01
The CpG island methylator phenotype (CIMP or CIMP-high) with extensive promoter methylation is a distinct phenotype in colorectal cancer. However, a choice of markers for CIMP has been controversial. A recent extensive investigation has selected five methylation markers (CACNA1G, IGF2, NEUROG1, RUNX3, and SOCS1) as surrogate markers for epigenomic aberrations in tumor. The use of these markers as a CIMP-specific panel needs to be validated by an independent, large dataset. Using MethyLight assays on 920 colorectal cancers from two large prospective cohort studies, we quantified DNA methylation in eight CIMP-specific markers [the above five plus CDKN2A (p16), CRABP1, and MLH1]. A CIMP-high cutoff was set at > or = 6/8 or > or = 5/8 methylated promoters, based on tumor distribution and BRAF/KRAS mutation frequencies. All but two very specific markers [MLH1 (98% specific) and SOCS1 (93% specific)] demonstrated > or = 85% sensitivity and > or = 80% specificity, indicating overall good concordance in methylation patterns and good performance of these markers. Based on sensitivity, specificity, and false positives and negatives, the eight markers were ranked in order as: RUNX3, CACNA1G, IGF2, MLH1, NEUROG1, CRABP1, SOCS1, and CDKN2A. In conclusion, a panel of markers including at least RUNX3, CACNA1G, IGF2, and MLH1 can serve as a sensitive and specific marker panel for CIMP-high.
Mena, Carlos; Fuentes, Eduardo; Ormazábal, Yony; Palomo-Vélez, Gonzalo; Palomo, Iván
2015-01-01
This study examined the association between access to urban green spaces and markets with anthropometric measurements, biological markers, sociodemographic, and healthy lifestyle. Geographic information systems were used to establish a correlation between environmental features and cardiovascular risk parameters. A total number of 832 (age range 18-74 years) individuals were selected for this study. Body mass index was significantly and positively related to the distance to parks (ρ = 0.079, p < 0.05), but negatively related to the distance to markets (ρ = -0.125, p < 0.05). In addition, waist circumference was similar and positively related to distance to parks (ρ = 0.097, p < 0.05) and negatively related to distance to markets (ρ = -0.092, p < 0.05). With respect to biochemical parameters, when there was an increase in the distance to markets, high-density lipoprotein cholesterol increased and glycemia decreased. The results of this study suggest the importance of the role of environmental factors such as parks and markets in the development of cardiovascular risk.
Nestin expression in neuroepithelial tumors.
Schiffer, Davide; Manazza, Andrea; Tamagno, Ilaria
2006-05-29
Nestin is a marker of early stages of neurocytogenesis. It has been studied in 50 neuroepithelial tumors, mostly gliomas of different malignancy grades, by immunohistochemistry, immunofluorescence, immunoblotting, and confocal microscopy and compared with GFAP and Vimentin. As an early marker of differentiation, Nestin is almost not expressed in diffuse astrocytomas, variably expressed in anaplastic astrocytomas and strongly and irregularly expressed in glioblastomas. Negative in oligodendrogliomas, it stains ependymomas and shows a gradient of expression in pilocytic astrocytomas. In glioblastomas, Nestin distribution does not completely correspond to that of GFAP and Vimentin with which its expression varies in tumor cells in a complementary way, as confirmed by confocal microscopy. Tumor cells can thus either derive from or differentiate toward the neurocytogenetic stages. Hypothetically, they could be put in relation with radial glia where during embriogenesis the three antigens are successively expressed. Completely negative cells of invasive or recurrent glioblastomas may represent malignant selected clones after accumulation of mutations or early stem cells not expressing antigens.
Schomberg, Jessica; Schöne, Benjamin; Gruber, Thomas; Quirin, Markus
2016-06-01
Previous research has demonstrated that negative affect influences attentional processes. Here, we investigate whether pre-experimental negative affect predicts a hypervigilant neural response as indicated by increased event-related potential amplitudes in response to neutral and positive visual stimuli. In our study, seventeen male participants filled out the German version of the positive and negative affect schedule (Watson et al. in J Pers Soc Psychol 54:1063-1070, 1988; Krohne et al. in Diagnostica 42:139-156, 1996) and subsequently watched positive (erotica, extreme sports, beautiful women) and neutral (daily activities) photographs while electroencephalogram was recorded. In line with our hypothesis, low state negative affect but not (reduced) positive affect predicted an increase in the first positive event-related potential amplitude P1 as a typical marker of increased selective attention. As this effect occurred in response to non-threatening picture conditions, negative affect may foster an individual's general hypervigilance, a state that has formerly been associated with psychopathology only.
Spiked GBS: A unified, open platform for single marker genotyping and whole-genome profiling
USDA-ARS?s Scientific Manuscript database
In plant breeding, there are two primary applications for DNA markers in selection: 1) selection of known genes using a single marker assay (marker-assisted selection; MAS); and 2) whole-genome profiling and prediction (genomic selection; GS). Typically, marker platforms have addressed only one of t...
Detection of immunocytological markers in photomicroscopic images
NASA Astrophysics Data System (ADS)
Friedrich, David; zur Jacobsmühlen, Joschka; Braunschweig, Till; Bell, André; Chaisaowong, Kraisorn; Knüchel-Clarke, Ruth; Aach, Til
2012-03-01
Early detection of cervical cancer can be achieved through visual analysis of cell anomalies. The established PAP smear achieves a sensitivity of 50-90%, most false negative results are caused by mistakes in the preparation of the specimen or reader variability in the subjective, visual investigation. Since cervical cancer is caused by human papillomavirus (HPV), the detection of HPV-infected cells opens new perspectives for screening of precancerous abnormalities. Immunocytochemical preparation marks HPV-positive cells in brush smears of the cervix with high sensitivity and specificity. The goal of this work is the automated detection of all marker-positive cells in microscopic images of a sample slide stained with an immunocytochemical marker. A color separation technique is used to estimate the concentrations of the immunocytochemical marker stain as well as of the counterstain used to color the nuclei. Segmentation methods based on Otsu's threshold selection method and Mean Shift are adapted to the task of segmenting marker-positive cells and their nuclei. The best detection performance of single marker-positive cells was achieved with the adapted thresholding method with a sensitivity of 95.9%. The contours differed by a modified Hausdorff Distance (MHD) of 2.8 μm. Nuclei of single marker positive cells were detected with a sensitivity of 95.9% and MHD = 1.02 μm.
Sajid, Mohammed; Chevalley-Maurel, Séverine; Ramesar, Jai; Klop, Onny; Franke-Fayard, Blandine M. D.; Janse, Chris J.; Khan, Shahid M.
2011-01-01
Research on the biology of malaria parasites has greatly benefited from the application of reverse genetic technologies, in particular through the analysis of gene deletion mutants and studies on transgenic parasites that express heterologous or mutated proteins. However, transfection in Plasmodium is limited by the paucity of drug-selectable markers that hampers subsequent genetic modification of the same mutant. We report the development of a novel ‘gene insertion/marker out’ (GIMO) method for two rodent malaria parasites, which uses negative selection to rapidly generate transgenic mutants ready for subsequent modifications. We have created reference mother lines for both P. berghei ANKA and P. yoelii 17XNL that serve as recipient parasites for GIMO-transfection. Compared to existing protocols GIMO-transfection greatly simplifies and speeds up the generation of mutants expressing heterologous proteins, free of drug-resistance genes, and requires far fewer laboratory animals. In addition we demonstrate that GIMO-transfection is also a simple and fast method for genetic complementation of mutants with a gene deletion or mutation. The implementation of GIMO-transfection procedures should greatly enhance Plasmodium reverse-genetic research. PMID:22216235
Human Commercial Models' Eye Colour Shows Negative Frequency-Dependent Selection.
Forti, Isabela Rodrigues Nogueira; Young, Robert John
2016-01-01
In this study we investigated the eye colour of human commercial models registered in the UK (400 female and 400 male) and Brazil (400 female and 400 male) to test the hypothesis that model eye colour frequency was the result of negative frequency-dependent selection. The eye colours of the models were classified as: blue, brown or intermediate. Chi-square analyses of data for countries separated by sex showed that in the United Kingdom brown eyes and intermediate colours were significantly more frequent than expected in comparison to the general United Kingdom population (P<0.001). In Brazil, the most frequent eye colour brown was significantly less frequent than expected in comparison to the general Brazilian population. These results support the hypothesis that model eye colour is the result of negative frequency-dependent selection. This could be the result of people using eye colour as a marker of genetic diversity and finding rarer eye colours more attractive because of the potential advantage more genetically diverse offspring that could result from such a choice. Eye colour may be important because in comparison to many other physical traits (e.g., hair colour) it is hard to modify, hide or disguise, and it is highly polymorphic.
Argov, Tal; Rabinovich, Lev; Sigal, Nadejda; Herskovits, Anat A
2017-03-15
Construction of Listeria monocytogenes mutants by allelic exchange has been laborious and time-consuming due to lack of proficient selection markers for the final recombination event, that is, a marker conveying substance sensitivity to the bacteria bearing it, enabling the exclusion of merodiploids and selection for plasmid loss. In order to address this issue, we engineered a counterselection marker based on a mutated phenylalanyl-tRNA synthetase gene ( pheS* ). This mutation renders the phenylalanine-binding site of the enzyme more promiscuous and allows the binding of the toxic p -chloro-phenylalanine analog ( p -Cl-phe) as a substrate. When pheS* is introduced into L. monocytogenes and highly expressed under control of a constitutively active promoter, the bacteria become sensitive to p -Cl-phe supplemented in the medium. This enabled us to utilize pheS* as a negative selection marker and generate a novel, efficient suicide vector for allelic exchange in L. monocytogenes We used this vector to investigate the monocin genomic region in L. monocytogenes strain 10403S by constructing deletion mutants of the region. We have found this region to be active and to cause bacterial lysis upon mitomycin C treatment. The future applications of such an effective counterselection system, which does not require any background genomic alterations, are vast, as it can be modularly used in various selection systems (e.g., genetic screens). We expect this counterselection marker to be a valuable genetic tool in research on L. monocytogenes IMPORTANCE L. monocytogenes is an opportunistic intracellular pathogen and a widely studied model organism. An efficient counterselection marker is a long-standing need in Listeria research for improving the ability to design and perform various genetic manipulations and screening systems for different purposes. We report the construction and utilization of an efficient suicide vector for allelic exchange which can be conjugated, leaves no marker in the bacterial chromosome, and does not require the use of sometimes leaky inducible promoters. This highly efficient genome editing tool for L. monocytogenes will allow for rapid sequential mutagenesis, introduction of point mutations, and design of screening systems. We anticipate that it will be extensively used by the research community and yield novel insights into the diverse fields studied using this model organism. Copyright © 2017 American Society for Microbiology.
Gianfrilli, P; Pantosti, A; Luzzi, I
1985-01-01
Direct gas-liquid chromatography of faecal specimens with isocaproic acid as a marker was used for the rapid diagnosis of Clostridium difficile associated diarrhoeal diseases. Ninety stools were examined and results were compared with conventional culture on selective medium and cytotoxin assay in tissue culture. Using a combined analysis of isocaproic acid and butyric acid peak heights we defined three categories: positive, negative, and indeterminate. When the indeterminate group was excluded, the positive and negative predictive values of gas-liquid chromatography analysis were 86.9% and 85% respectively compared with culture and 71.4% and 95% respectively compared with cytotoxin assay. PMID:4008667
Serum ALT levels as a surrogate marker for serum HBV DNA levels in HBeAg-negative pregnant women.
Sangfelt, Per; Von Sydow, Madeleine; Uhnoo, Ingrid; Weiland, Ola; Lindh, Gudrun; Fischler, Björn; Lindgren, Susanne; Reichard, Olle
2004-01-01
In Stockholm, Sweden, the majority of pregnant women positive for hepatitis B surface antigen (HBsAg) are hepatitis Be antigen (HBeAg) negative. Newborns to HBeAg positive mothers receive vaccination and hepatitis B immunoglobulin (HBIg). Newborns to HBeAg negative mothers receive vaccine and HBIg only if the mothers have elevated ALT levels. The aim of this study was to retrospectively evaluate ALT levels as a surrogate marker for HBV DNA levels in HBeAg negative carrier mothers. Altogether 8947 pregnant women were screened for HBV markers from 1999 to 2001 at the Virology Department, Karolinska Hospital. Among mothers screened 192 tested positive for HBsAg (2.2%). 13 of these samples could not be retrieved. Of the remaining 179 sera, 8 (4%) tested positive for HBeAg and 171 (95.5%) were HBeAg negative. Among the HBeAg negative mothers, 9 had HBV DNA levels > 10(5) copies/ml, and of these 7 had normal ALT levels indicating low sensitivity of an elevated ALT level as a surrogate marker for high HBV DNA level. Furthermore, no correlation was found between ALT and HBV DNA levels. Hence, it is concluded that the use of ALT as a surrogate marker for high viral replication in HBeAg negative mothers could be questioned.
Zhang, Bo; Zhang, Lin; Dai, Ruixue; Yu, Meiying; Zhao, Guoping; Ding, Xiaoming
2013-01-01
Streptomyces bacteria are known for producing important natural compounds by secondary metabolism, especially antibiotics with novel biological activities. Functional studies of antibiotic-biosynthesizing gene clusters are generally through homologous genomic recombination by gene-targeting vectors. Here, we present a rapid and efficient method for construction of gene-targeting vectors. This approach is based on Streptomyces phage φBT1 integrase-mediated multisite in vitro site-specific recombination. Four 'entry clones' were assembled into a circular plasmid to generate the destination gene-targeting vector by a one-step reaction. The four 'entry clones' contained two clones of the upstream and downstream flanks of the target gene, a selectable marker and an E. coli-Streptomyces shuttle vector. After targeted modification of the genome, the selectable markers were removed by φC31 integrase-mediated in vivo site-specific recombination between pre-placed attB and attP sites. Using this method, part of the calcium-dependent antibiotic (CDA) and actinorhodin (Act) biosynthetic gene clusters were deleted, and the rrdA encoding RrdA, a negative regulator of Red production, was also deleted. The final prodiginine production of the engineered strain was over five times that of the wild-type strain. This straightforward φBT1 and φC31 integrase-based strategy provides an alternative approach for rapid gene-targeting vector construction and marker removal in streptomycetes.
Nicholson, S.; Richard, J.; Sainsbury, C.; Halcrow, P.; Kelly, P.; Angus, B.; Wright, C.; Henry, J.; Farndon, J. R.; Harris, A. L.
1991-01-01
More accurate criteria are required for the selection of patients with node-negative breast cancer for systemic adjuvant therapy. Expression of epidermal growth factor receptor (EGFr) has been shown previously to be inversely related to oestrogen receptor (ER) in patients with operable breast cancer and to be associated with a poorer prognosis. Analysis of EGFr and ER was performed on tumour samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumours with greater than 10 fmol mg-1 I125-EGF binding (EGFr+) and 47% (109) and cystolic ER concentrations greater than 5 fmol mg-1 (ER+), with a marked inverse relationship between EGFr and ER (P less than 0.00001). In a univariate analysis EGFr was second only to axillary node status as a prognostic marker for all patients both in terms of relapse-free and overall survival (P less than 0.001, log rank). For patients with histologically negative axillary nodes EGFr was superior to ER in predicting relapse and survival (P less than 0.01 and P less than 0.005 respectively compared to P less than 0.1 and P less than 0.1, log rank). In a multivariate (Cox model) analysis only EGFr, out of EGFr, ER, size and grade, was predictive for either relapse-free or overall survival for patients with node-negative disease (P = 0.05 and P = 0.026 respectively). EGFr has been shown to be a marker of poor prognosis for patients with node-negative breast cancer. Since patients with EGFr+ tumours are unlikely to respond to hormone therapy it may be possible to select them for trials of systemic adjuvant chemotherapy. PMID:1846551
Nicholson, S; Richard, J; Sainsbury, C; Halcrow, P; Kelly, P; Angus, B; Wright, C; Henry, J; Farndon, J R; Harris, A L
1991-01-01
More accurate criteria are required for the selection of patients with node-negative breast cancer for systemic adjuvant therapy. Expression of epidermal growth factor receptor (EGFr) has been shown previously to be inversely related to oestrogen receptor (ER) in patients with operable breast cancer and to be associated with a poorer prognosis. Analysis of EGFr and ER was performed on tumour samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumours with greater than 10 fmol mg-1 I125-EGF binding (EGFr+) and 47% (109) and cystolic ER concentrations greater than 5 fmol mg-1 (ER+), with a marked inverse relationship between EGFr and ER (P less than 0.00001). In a univariate analysis EGFr was second only to axillary node status as a prognostic marker for all patients both in terms of relapse-free and overall survival (P less than 0.001, log rank). For patients with histologically negative axillary nodes EGFr was superior to ER in predicting relapse and survival (P less than 0.01 and P less than 0.005 respectively compared to P less than 0.1 and P less than 0.1, log rank). In a multivariate (Cox model) analysis only EGFr, out of EGFr, ER, size and grade, was predictive for either relapse-free or overall survival for patients with node-negative disease (P = 0.05 and P = 0.026 respectively). EGFr has been shown to be a marker of poor prognosis for patients with node-negative breast cancer. Since patients with EGFr+ tumours are unlikely to respond to hormone therapy it may be possible to select them for trials of systemic adjuvant chemotherapy.
CA19-9 serum levels predict micrometastases in patients with gastric cancer
Potrc, Stojan; Mis, Katarina; Plankl, Mojca; Mars, Tomaz
2016-01-01
Abstract Background We explored the prognostic value of the up-regulated carbohydrate antigen (CA19-9) in node-negative patients with gastric cancer as a surrogate marker for micrometastases. Patients and methods Micrometastases were determined using reverse transcription quantitative polymerase chain reaction (RT-qPCR) for a subgroup of 30 node-negative patients. This group was used to determine the cut-off for preoperative CA19-9 serum levels as a surrogate marker for micrometastases. Then 187 node-negative T1 to T4 patients were selected to validate the predictive value of this CA19-9 threshold. Results Patients with micrometastases had significantly higher preoperative CA19-9 serum levels compared to patients without micrometastases (p = 0.046). CA19-9 serum levels were significantly correlated with tumour site, tumour diameter, and perineural invasion. Although not reaching significance, subgroup analysis showed better five-year survival rates for patients with CA19-9 serum levels below the threshold, compared to patients with CA19-9 serum levels above the cut-off. The cumulative survival for T2 to T4 node-negative patients was significantly better with CA19-9 serum levels below the cut-off (p = 0.04). Conclusions Preoperative CA19-9 serum levels can be used to predict higher risk for haematogenous spread and micrometastases in node-negative patients. However, CA19-9 serum levels lack the necessary sensitivity and specificity to reliably predict micrometastases. PMID:27247553
Genomic selection in plant breeding.
Newell, Mark A; Jannink, Jean-Luc
2014-01-01
Genomic selection (GS) is a method to predict the genetic value of selection candidates based on the genomic estimated breeding value (GEBV) predicted from high-density markers positioned throughout the genome. Unlike marker-assisted selection, the GEBV is based on all markers including both minor and major marker effects. Thus, the GEBV may capture more of the genetic variation for the particular trait under selection.
At the Crossroads of Cancer Stem Cells, Radiation Biology, and Radiation Oncology.
Gerweck, Leo E; Wakimoto, Hiroaki
2016-03-01
Reports that a small subset of tumor cells initiate and sustain tumor growth, are resistant to radiation and drugs, and bear specific markers have led to an explosion of cancer stem cell research. These reports imply that the evaluation of therapeutic response by changes in tumor volume is misleading, as volume changes reflect the response of the sensitive rather than the resistant tumorigenic cell population. The reports further suggest that the marker-based selection of the tumor cell population will facilitate the development of radiation treatment schedules, sensitizers, and drugs that specifically target the resistant tumorigenic cells that give rise to treatment failure. This review presents evidence that contests the observations that cancer stem cell markers reliably identify the subset of tumor cells that sustain tumor growth and that the marker-identified population is radioresistant relative to the marker-negative cells. Experimental studies show that cells and tumors that survive large radiation doses are not more radioresistant than unirradiated cells and tumors, and also show that the intrinsic radiosensitivity of unsorted colony-forming tumor cells, in combination with the fraction of unsorted tumor cells that are tumor initiating, predicts tumor radiocurability. ©2016 American Association for Cancer Research.
NASA Astrophysics Data System (ADS)
Kwak, Kyuju; Kumar, S. Senthil; Lee, Dongil
2012-06-01
We report here the selective determination of dopamine (DA) using quantum-sized gold nanoparticles coated with charge selective ligands. Glutathione protected gold nanoparticles (GS-Au25) were synthesized and immobilized into a sol-gel matrix via thiol linkers. The GS-Au25 modified sol-gel electrode was found to show excellent electrocatalytic activity towards the oxidation of DA but no activity towards the oxidation of ascorbic acid. The role of electrostatic charge in the selective electrocatalytic activity of GS-Au25 was verified by voltammetry of redox markers carrying opposite charges. The pH dependent sensitivity for the determination of DA further confirmed the charge screening effect of GS-Au25. Mechanistic investigation revealed that the selectivity is attained by the selective formation of an electrostatic complex between the negatively charged GS-Au25 and DA cation. The GS-Au25 modified sol-gel electrode also showed excellent selectivity for DA in the presence of an interferent, ascorbic acid.We report here the selective determination of dopamine (DA) using quantum-sized gold nanoparticles coated with charge selective ligands. Glutathione protected gold nanoparticles (GS-Au25) were synthesized and immobilized into a sol-gel matrix via thiol linkers. The GS-Au25 modified sol-gel electrode was found to show excellent electrocatalytic activity towards the oxidation of DA but no activity towards the oxidation of ascorbic acid. The role of electrostatic charge in the selective electrocatalytic activity of GS-Au25 was verified by voltammetry of redox markers carrying opposite charges. The pH dependent sensitivity for the determination of DA further confirmed the charge screening effect of GS-Au25. Mechanistic investigation revealed that the selectivity is attained by the selective formation of an electrostatic complex between the negatively charged GS-Au25 and DA cation. The GS-Au25 modified sol-gel electrode also showed excellent selectivity for DA in the presence of an interferent, ascorbic acid. Electronic supplementary information (ESI) available: TEM image of GS-Au25, SWV of GS-Au25 in solution, effect of scan rate on the CV of GS-Au25ME, CVs of DA and AA at the bare GCE and CVs of GS-Au25ME at different pHs. See DOI: 10.1039/c2nr30481c
An ecological genetic delineation of local seed-source provenance for ecological restoration
Krauss, Siegfried L; Sinclair, Elizabeth A; Bussell, John D; Hobbs, Richard J
2013-01-01
An increasingly important practical application of the analysis of spatial genetic structure within plant species is to help define the extent of local provenance seed collection zones that minimize negative impacts in ecological restoration programs. Here, we derive seed sourcing guidelines from a novel range-wide assessment of spatial genetic structure of 24 populations of Banksia menziesii (Proteaceae), a widely distributed Western Australian tree of significance in local ecological restoration programs. An analysis of molecular variance (AMOVA) of 100 amplified fragment length polymorphism (AFLP) markers revealed significant genetic differentiation among populations (ΦPT = 0.18). Pairwise population genetic dissimilarity was correlated with geographic distance, but not environmental distance derived from 15 climate variables, suggesting overall neutrality of these markers with regard to these climate variables. Nevertheless, Bayesian outlier analysis identified four markers potentially under selection, although these were not correlated with the climate variables. We calculated a global R-statistic using analysis of similarities (ANOSIM) to test the statistical significance of population differentiation and to infer a threshold seed collection zone distance of ∼60 km (all markers) and 100 km (outlier markers) when genetic distance was regressed against geographic distance. Population pairs separated by >60 km were, on average, twice as likely to be significantly genetically differentiated than population pairs separated by <60 km, suggesting that habitat-matched sites within a 30-km radius around a restoration site genetically defines a local provenance seed collection zone for B. menziesii. Our approach is a novel probability-based practical solution for the delineation of a local seed collection zone to minimize negative genetic impacts in ecological restoration. PMID:23919158
Daffner, Kirk R; Zhuravleva, Tatyana Y; Sun, Xue; Tarbi, Elise C; Haring, Anna E; Rentz, Dorene M; Holcomb, Phillip J
2012-02-01
Numerous studies have demonstrated that selective attention to color is associated with a larger neural response under attend than ignore conditions, but have not addressed whether this difference reflects enhanced activity under attend or suppressed activity under ignore. In this study, a color-neutral condition was included, which presented stimuli physically identical to those under attend and ignore conditions, but in which color was not task relevant. Attention to color did not modulate the early sensory-evoked P1 and N1 components. Traditional ERP markers of early selection (the anterior Selection Positivity and posterior Selection Negativity) did not differ between the attend and neutral conditions, arguing against a mechanism of enhanced activity. However, there were markedly reduced responses under the ignore relative to the neutral condition, consistent with the view that early selection mechanisms reflect suppression of neural activity under the ignore condition. Copyright © 2011 Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Genomic selection (GS) and marker-assisted selection (MAS) rely on marker-trait associations and are both routinely used for breeding purposes. Although similar, these two approaches differ in their applications and how markers are used to estimate breeding values. In this study, GS and MAS were com...
Optimal selection of markers for validation or replication from genome-wide association studies.
Greenwood, Celia M T; Rangrej, Jagadish; Sun, Lei
2007-07-01
With reductions in genotyping costs and the fast pace of improvements in genotyping technology, it is not uncommon for the individuals in a single study to undergo genotyping using several different platforms, where each platform may contain different numbers of markers selected via different criteria. For example, a set of cases and controls may be genotyped at markers in a small set of carefully selected candidate genes, and shortly thereafter, the same cases and controls may be used for a genome-wide single nucleotide polymorphism (SNP) association study. After such initial investigations, often, a subset of "interesting" markers is selected for validation or replication. Specifically, by validation, we refer to the investigation of associations between the selected subset of markers and the disease in independent data. However, it is not obvious how to choose the best set of markers for this validation. There may be a prior expectation that some sets of genotyping data are more likely to contain real associations. For example, it may be more likely for markers in plausible candidate genes to show disease associations than markers in a genome-wide scan. Hence, it would be desirable to select proportionally more markers from the candidate gene set. When a fixed number of markers are selected for validation, we propose an approach for identifying an optimal marker-selection configuration by basing the approach on minimizing the stratified false discovery rate. We illustrate this approach using a case-control study of colorectal cancer from Ontario, Canada, and we show that this approach leads to substantial reductions in the estimated false discovery rates in the Ontario dataset for the selected markers, as well as reductions in the expected false discovery rates for the proposed validation dataset. Copyright 2007 Wiley-Liss, Inc.
2013-01-01
Background The cloning of gene sequences forms the basis for many molecular biological studies. One important step in the cloning process is the isolation of bacterial transformants carrying vector DNA. This involves a vector-encoded selectable marker gene, which in most cases, confers resistance to an antibiotic. However, there are a number of circumstances in which a different selectable marker is required or may be preferable. Such situations can include restrictions to host strain choice, two phase cloning experiments and mutagenesis experiments, issues that result in additional unnecessary cloning steps, in which the DNA needs to be subcloned into a vector with a suitable selectable marker. Results We have used restriction enzyme mediated gene disruption to modify the selectable marker gene of a given vector by cloning a different selectable marker gene into the original marker present in that vector. Cloning a new selectable marker into a pre-existing marker was found to change the selection phenotype conferred by that vector, which we were able to demonstrate using multiple commonly used vectors and multiple resistance markers. This methodology was also successfully applied not only to cloning vectors, but also to expression vectors while keeping the expression characteristics of the vector unaltered. Conclusions Changing the selectable marker of a given vector has a number of advantages and applications. This rapid and efficient method could be used for co-expression of recombinant proteins, optimisation of two phase cloning procedures, as well as multiple genetic manipulations within the same host strain without the need to remove a pre-existing selectable marker in a previously genetically modified strain. PMID:23497512
USDA-ARS?s Scientific Manuscript database
Breeding and selection for the traits with polygenic inheritance is a challenging task that can be done by phenotypic selection, by marker-assisted selection or by genome wide selection. We tested predictive ability of four selection models in a biparental population genotyped with 95 SNP markers an...
Cisgenic apple trees; development, characterization, and performance
Krens, Frans A.; Schaart, Jan G.; van der Burgh, Aranka M.; Tinnenbroek-Capel, Iris E. M.; Groenwold, Remmelt; Kodde, Linda P.; Broggini, Giovanni A. L.; Gessler, Cesare; Schouten, Henk J.
2015-01-01
Two methods were developed for the generation of cisgenic apples. Both have been successfully applied producing trees. The first method avoids the use of any foreign selectable marker genes; only the gene-of-interest is integrated between the T-DNA border sequences. The second method makes use of recombinase-based marker excision. For the first method we used the MdMYB10 gene from a red-fleshed apple coding for a transcription factor involved in regulating anthocyanin biosynthesis. Red plantlets were obtained and presence of the cisgene was confirmed. Plantlets were grafted and grown in a greenhouse. After 3 years, the first flowers appeared, showing red petals. Pollination led to production of red-fleshed cisgenic apples. The second method used the pM(arker)F(ree) vector system, introducing the scab resistance gene Rvi6, derived from apple. Agrobacterium-mediated transformation, followed by selection on kanamycin, produced genetically modified apple lines. Next, leaves from in vitro material were treated to activate the recombinase leading to excision of selection genes. Subsequently, the leaf explants were subjected to negative selection for marker-free plantlets by inducing regeneration on medium containing 5-fluorocytosine. After verification of the marker-free nature, the obtained plants were grafted onto rootstocks. Young trees from four cisgenic lines and one intragenic line, all containing Rvi6, were planted in an orchard. Appropriate controls were incorporated in this trial. We scored scab incidence for three consecutive years on leaves after inoculations with Rvi6-avirulent strains. One cisgenic line and the intragenic line performed as well as the resistant control. In 2014 trees started to overcome their juvenile character and formed flowers and fruits. The first results of scoring scab symptoms on apple fruits were obtained. Apple fruits from susceptible controls showed scab symptoms, while fruits from cisgenic and intragenic lines were free of scab. PMID:25964793
Peptide biomarkers used for the selective breeding of a complex polygenic trait in honey bees.
Guarna, M Marta; Hoover, Shelley E; Huxter, Elizabeth; Higo, Heather; Moon, Kyung-Mee; Domanski, Dominik; Bixby, Miriam E F; Melathopoulos, Andony P; Ibrahim, Abdullah; Peirson, Michael; Desai, Suresh; Micholson, Derek; White, Rick; Borchers, Christoph H; Currie, Robert W; Pernal, Stephen F; Foster, Leonard J
2017-08-21
We present a novel way to select for highly polygenic traits. For millennia, humans have used observable phenotypes to selectively breed stronger or more productive livestock and crops. Selection on genotype, using single-nucleotide polymorphisms (SNPs) and genome profiling, is also now applied broadly in livestock breeding programs; however, selection on protein/peptide or mRNA expression markers has not yet been proven useful. Here we demonstrate the utility of protein markers to select for disease-resistant hygienic behavior in the European honey bee (Apis mellifera L.). Robust, mechanistically-linked protein expression markers, by integrating cis- and trans- effects from many genomic loci, may overcome limitations of genomic markers to allow for selection. After three generations of selection, the resulting marker-selected stock outperformed an unselected benchmark stock in terms of hygienic behavior, and had improved survival when challenged with a bacterial disease or a parasitic mite, similar to bees selected using a phenotype-based assessment for this trait. This is the first demonstration of the efficacy of protein markers for industrial selective breeding in any agricultural species, plant or animal.
Screening white spot syndrome virus (WSSV)-resistant molecular markers from Fenneropenaeus chinensis
NASA Astrophysics Data System (ADS)
Wu, Yingying; Meng, Xianhong; Kong, Jie; Luan, Sheng; Luo, Kun; Wang, Qingyin; Zheng, Yongyun
2017-02-01
White spot syndrome virus (WSSV)-resistant molecular markers were screened from the selectively bred new variety `Huanghai No. 2' of Fenneropenaeus chinensis using unlabeled-probe high-resolution melting (HRM) technique. After the artificial infection with WSSV, the first 96 dead shrimps and the last 96 surviving shrimps were collected, representing WSSV-susceptible and -resistant populations, respectively. The genotypes at well-developed 39 single nucleotide polymorphisms (SNPs) loci were obtained. As revealed in the Chi-square test, 3 SNPs, genotype A/A of contig C364-89AT, genotype A/A of C2635-527CA and genotype C/T of contig C12355-592CT, were positively correlated with disease-resistance traits. Other 2 SNPs, genotype G/G of contig C283-145AG and genotype C/C of contig C12355-592CT, were negatively correlated. Moreover, analysis with BlastX program for disease-resistant SNPs indicated that 3 contigs, Contig283, Contig364 and Contig12355, matched to the functional genes of effector caspase of Penaeus monodon, peptide transporter family 1-like protein, and 40S ribosomal protein S2 of Perca flavescens with high sequence similarity. The results will be helpful to provide theoretical and technical supports for molecular marker-assisted selective breeding of F. chinensis.
Genomic selection in plant breeding
USDA-ARS?s Scientific Manuscript database
Genomic selection (GS) is a method to predict the genetic value of selection candidates based on the genomic estimated breeding value (GEBV) predicted from high-density markers positioned throughout the genome. Unlike marker-assisted selection, the GEBV is based on all markers including both minor ...
Tong, Qi; Liu, Xu; Su, Feng; Quan, Fusheng; Guo, Zekun; Zhang, Yong
2013-01-01
Antibiotic selectable marker genes have been widely used to generate transgenic animals. Once transgenic animals have been obtained, the selectable marker is no longer necessary but raises public concerns regarding biological safety. The aim of this study was to prepare competent antibiotic selectable marker free transgenic cells for somatic cell nuclear transfer (SCNT). PhiC31 intergrase was used to insert a transgene cassette into a “safe harbor” in the bovine genome. Then, Cre recombinase was employed to excise the selectable marker under the monitoring of a fluorescent double reporter. By visually tracking the phenotypic switch from red to green fluorescence, antibiotic selectable marker free cells were easily detected and sorted by fluorescence-activated cell sorting. For safety, we used phiC31 mRNA and cell-permeant Cre protein in this study. When used as donor nuclei for SCNT, these safe harbor integrated marker-free transgenic cells supported a similar developmental competence of SCNT embryos compared with that of non-transgenic cells. After embryo transfer, antibiotic selectable marker free transgenic cattle were generated and anti-bacterial recombinant human β-defensin-3 in milk was detected during their lactation period. Thus, this approach offers a rapid and safe alternative to produce antibiotic selectable marker free transgenic farm animals, thereby making it a valuable tool to promote the healthy development and welfare of transgenic farm animals. PMID:23658729
Microbial Risk Markers for Childhood Caries in Pediatricians’ Offices
Kanasi, E.; Johansson, I.; Lu, S.C.; Kressin, N.R.; Nunn, M.E.; Kent, R.; Tanner, A.C.R.
2010-01-01
Dental caries in pre-school children has significant public health and health disparity implications. To determine microbial risk markers for this infection, this study aimed to compare the microbiota of children with early childhood caries with that of caries-free children. Plaque samples from incisors, molars, and the tongue from 195 children attending pediatricians’ offices were assayed by 74 DNA probes and by PCR to Streptococcus mutans. Caries-associated factors included visible plaque, child age, race, and snacking habits. Species were detected more frequently from tooth than tongue samples. Lactobacillus gasseri (p < 0.01), Lactobacillus fermentum, Lactobacillus vaginalis, and S. mutans with Streptococcus sobrinus (all p < 0.05) were positively associated with caries. By multifactorial analysis, the probiotic Lactobacillus acidophilus was negatively associated with caries. Prevotella nigrescens was the only species (p < 0.05) significantly associated with caries by the ‘false discovery’ rate. Analysis of the data suggests that selected Lactobacillus species, in addition to mutans streptococci, are risk markers for early childhood caries. PMID:20164496
Beaulieu, Jean; Doerksen, Trevor K; MacKay, John; Rainville, André; Bousquet, Jean
2014-12-02
Genomic selection (GS) may improve selection response over conventional pedigree-based selection if markers capture more detailed information than pedigrees in recently domesticated tree species and/or make it more cost effective. Genomic prediction accuracies using 1748 trees and 6932 SNPs representative of as many distinct gene loci were determined for growth and wood traits in white spruce, within and between environments and breeding groups (BG), each with an effective size of Ne ≈ 20. Marker subsets were also tested. Model fits and/or cross-validation (CV) prediction accuracies for ridge regression (RR) and the least absolute shrinkage and selection operator models approached those of pedigree-based models. With strong relatedness between CV sets, prediction accuracies for RR within environment and BG were high for wood (r = 0.71-0.79) and moderately high for growth (r = 0.52-0.69) traits, in line with trends in heritabilities. For both classes of traits, these accuracies achieved between 83% and 92% of those obtained with phenotypes and pedigree information. Prediction into untested environments remained moderately high for wood (r ≥ 0.61) but dropped significantly for growth (r ≥ 0.24) traits, emphasizing the need to phenotype in all test environments and model genotype-by-environment interactions for growth traits. Removing relatedness between CV sets sharply decreased prediction accuracies for all traits and subpopulations, falling near zero between BGs with no known shared ancestry. For marker subsets, similar patterns were observed but with lower prediction accuracies. Given the need for high relatedness between CV sets to obtain good prediction accuracies, we recommend to build GS models for prediction within the same breeding population only. Breeding groups could be merged to build genomic prediction models as long as the total effective population size does not exceed 50 individuals in order to obtain high prediction accuracy such as that obtained in the present study. A number of markers limited to a few hundred would not negatively impact prediction accuracies, but these could decrease more rapidly over generations. The most promising short-term approach for genomic selection would likely be the selection of superior individuals within large full-sib families vegetatively propagated to implement multiclonal forestry.
Comparison of two alternative dominant selectable markers for wine yeast transformation.
Cebollero, Eduardo; Gonzalez, Ramon
2004-12-01
Genetic improvement of industrial yeast strains is restricted by the availability of selectable transformation markers. Antibiotic resistance markers have to be avoided for public health reasons, while auxotrophy markers are generally not useful for wine yeast strain transformation because most industrial Saccharomyces cerevisiae strains are prototrophic. For this work, we performed a comparative study of the usefulness of two alternative dominant selectable markers in both episomic and centromeric plasmids. Even though the selection for sulfite resistance conferred by FZF1-4 resulted in a larger number of transformants for a laboratory strain, the p-fluoro-DL-phenylalanine resistance conferred by ARO4-OFP resulted in a more suitable selection marker for all industrial strains tested. Both episomic and centromeric constructions carrying this marker resulted in transformation frequencies close to or above 10(3) transformants per microg of DNA for the three wine yeast strains tested.
Zhao, Y; Mette, M F; Gowda, M; Longin, C F H; Reif, J C
2014-06-01
Based on data from field trials with a large collection of 135 elite winter wheat inbred lines and 1604 F1 hybrids derived from them, we compared the accuracy of prediction of marker-assisted selection and current genomic selection approaches for the model traits heading time and plant height in a cross-validation approach. For heading time, the high accuracy seen with marker-assisted selection severely dropped with genomic selection approaches RR-BLUP (ridge regression best linear unbiased prediction) and BayesCπ, whereas for plant height, accuracy was low with marker-assisted selection as well as RR-BLUP and BayesCπ. Differences in the linkage disequilibrium structure of the functional and single-nucleotide polymorphism markers relevant for the two traits were identified in a simulation study as a likely explanation for the different trends in accuracies of prediction. A new genomic selection approach, weighted best linear unbiased prediction (W-BLUP), designed to treat the effects of known functional markers more appropriately, proved to increase the accuracy of prediction for both traits and thus closes the gap between marker-assisted and genomic selection.
Zhao, Y; Mette, M F; Gowda, M; Longin, C F H; Reif, J C
2014-01-01
Based on data from field trials with a large collection of 135 elite winter wheat inbred lines and 1604 F1 hybrids derived from them, we compared the accuracy of prediction of marker-assisted selection and current genomic selection approaches for the model traits heading time and plant height in a cross-validation approach. For heading time, the high accuracy seen with marker-assisted selection severely dropped with genomic selection approaches RR-BLUP (ridge regression best linear unbiased prediction) and BayesCπ, whereas for plant height, accuracy was low with marker-assisted selection as well as RR-BLUP and BayesCπ. Differences in the linkage disequilibrium structure of the functional and single-nucleotide polymorphism markers relevant for the two traits were identified in a simulation study as a likely explanation for the different trends in accuracies of prediction. A new genomic selection approach, weighted best linear unbiased prediction (W-BLUP), designed to treat the effects of known functional markers more appropriately, proved to increase the accuracy of prediction for both traits and thus closes the gap between marker-assisted and genomic selection. PMID:24518889
Ru, Sushan; Hardner, Craig; Carter, Patrick A; Evans, Kate; Main, Dorrie; Peace, Cameron
2016-01-01
Seedling selection identifies superior seedlings as candidate cultivars based on predicted genetic potential for traits of interest. Traditionally, genetic potential is determined by phenotypic evaluation. With the availability of DNA tests for some agronomically important traits, breeders have the opportunity to include DNA information in their seedling selection operations—known as marker-assisted seedling selection. A major challenge in deploying marker-assisted seedling selection in clonally propagated crops is a lack of knowledge in genetic gain achievable from alternative strategies. Existing models based on additive effects considering seed-propagated crops are not directly relevant for seedling selection of clonally propagated crops, as clonal propagation captures all genetic effects, not just additive. This study modeled genetic gain from traditional and various marker-based seedling selection strategies on a single trait basis through analytical derivation and stochastic simulation, based on a generalized seedling selection scheme of clonally propagated crops. Various trait-test scenarios with a range of broad-sense heritability and proportion of genotypic variance explained by DNA markers were simulated for two populations with different segregation patterns. Both derived and simulated results indicated that marker-based strategies tended to achieve higher genetic gain than phenotypic seedling selection for a trait where the proportion of genotypic variance explained by marker information was greater than the broad-sense heritability. Results from this study provides guidance in optimizing genetic gain from seedling selection for single traits where DNA tests providing marker information are available. PMID:27148453
Development of DArT-based PCR markers for selecting drought-tolerant spring barley.
Fiust, Anna; Rapacz, Marcin; Wójcik-Jagła, Magdalena; Tyrka, Mirosław
2015-08-01
The tolerance of spring barley (Hordeum vulgare L.) cultivars to spring drought is an important agronomic trait affecting crop yield and quality in Poland. Therefore, breeders require new molecular markers to select plants with lower spring drought susceptibility. With the advent of genomic selection technology, simple molecular tools may still be applicable to screen material for markers of the most important traits and in-depth genome scanning. In previous studies, diversity arrays technology (DArT)-based genetic maps were constructed for F2 populations of Polish fodder and malt barley elite breeding lines, and 15 and 18 quantitative trait loci (QTLs) related to spring drought tolerance were identified, respectively. In this paper, we show the results of a conversion of 30 DArT markers corresponding to 11 QTLs into simple sequence repeat (SSR) and sequence tagged site (STS) markers. Twenty-two polymorphic markers were obtained, including 13 DArT-based SSRs. Additionally, 31 SSR markers, located in close proximity to the DArT markers, were selected from the GrainGenes database and tested. Further analyses of 24 advanced breeding lines with different drought tolerances confirmed that five out of the 30 converted markers, as well as three out of the 31 additional SSR markers, were effective in marker-assisted selection for drought tolerance. The possible function of clones related to these markers in drought tolerance is discussed.
USDA-ARS?s Scientific Manuscript database
Marker assisted selection (MAS) has become widely used in perennial crop breeding programs to accelerate and enhance cultivar development via selection during the juvenile phase and parental selection prior to crossing. Next generation sequencing (NGS) has been widely used for whole genome molecular...
USDA-ARS?s Scientific Manuscript database
Marker assisted selection (MAS) is often employed in crop breeding programs to accelerate and enhance cultivar development, via selection during the juvenile phase and parental selection prior to crossing. Next generation sequencing (NGS) and its derivative technologies have been used for genome-wid...
Mago, Rohit; Zhang, P; Bariana, H S; Verlin, D C; Bansal, U K; Ellis, J G; Dundas, I S
2009-11-01
The use of major resistance genes is a cost-effective strategy for preventing stem rust epidemics in wheat crops. The stem rust resistance gene Sr39 provides resistance to all currently known pathotypes of Puccinia graminis f. sp. tritici (Pgt) including Ug99 (TTKSK) and was introgressed together with leaf rust resistance gene Lr35 conferring adult plant resistance to P. triticina (Pt), into wheat from Aegilops speltoides. It has not been used extensively in wheat breeding because of the presumed but as yet undocumented negative agronomic effects associated with Ae. speltoides chromatin. This investigation reports the production of a set of recombinants with shortened Ae. speltoides segments through induction of homoeologous recombination between the wheat and the Ae. speltoides chromosome. Simple PCR-based DNA markers were developed for resistant and susceptible genotypes (Sr39#22r and Sr39#50s) and validated across a set of recombinant lines and wheat cultivars. These markers will facilitate the pyramiding of ameliorated sources of Sr39 with other stem rust resistance genes that are effective against the Pgt pathotype TTKSK and its variants.
Ellenbogen, Mark A; Schwartzman, Alex E; Stewart, Jane; Walker, Claire-Dominique
2002-11-01
The effects of a stressful challenge on the processing of emotional words were examined in college students. Stress induction was achieved using a competitive computer task, where the individual either repeatedly lost or won against a confederate. Mood, attention, and cortisol were recorded during the study. There were four findings: (1) Participants in the negative stressor condition were faster to shift attention away from negative words than positive or neutral words; (2) attentional shifts away from negative words were associated with stress-induced mood lowering; (3) participants in the negative stress condition with elevated scores on the Beck Depression Inventory were slow to disengage attention from all stimuli; and (4) elevated depression scores were associated with lower cortisol change from baseline during the experimental phase, and with higher cortisol levels during the recovery phase. These findings point to information-processing strategies as a means to regulate emotion, and to atypical features of cognitive and adrenocortical function that may serve as putative risk markers of depression.
Immunohistochemical characterization of neoplastic cells of breast origin.
Noriega, Mariadelasmercedes; Paesani, Fernando; Perazzo, Florencia; Lago, Néstor; Krupitzki, Hugo; Nieto, Silvana; Garcia, Alejandro; Avagnina, Alejandra; Elsner, Boris; Denninghoff, Valeria Cecilia
2012-06-22
After skin cancer, breast cancer is the most common malignancy in women. Tumors of unknown origin account for 5-15% of malignant neoplasms, with 1.5% being breast cancer. An immunohistochemical panel with conventional and newer markers, such as mammaglobin, was selected for the detection of neoplastic cells of breast origin. The specific objectives are: 1) to determine the sensitivity and specificity of the panel, with a special emphasis on the inclusion of the mammaglobin marker, and 2) to compare immunohistochemistry performed on whole tissue sections and on tissue micro-array. Twenty-nine metastatic breast tumors were included and assumed as tumors of unknown origin. Other 48 biopsies of diverse tissues were selected and assumed as negative controls. Tissue Micro-Array was performed. Immunohistochemistry for mammaglobin, gross cystic disease fluid protein-15, estrogen receptor, progesterone receptor and cytokeratin 7 was done. Mammaglobin positive staining was observed in 10/29 cases, in 13/29 cases for gross cystic disease fluid protein-15, in 20/29 cases for estrogen receptor, in 9/29 cases for progesterone receptor, and in 25/29 cases for cytokeratin 7. Among the negative controls, mammaglobin was positive in 2/48, and gross cystic disease fluid protein-15 in 4/48. The inclusion of MAG antibody in the immunohistochemical panel for the detection of tumors of unknown origin contributed to the detection of metastasis of breast cancer. The diagnostic strategy with the highest positive predictive value (88%) included hormone receptors and mammaglobin in serial manner.
Hacker, Ulrich T; Schildhauer, Ines; Barroso, Margarita Céspedes; Kofler, David M; Gerner, Franz M; Mysliwietz, Josef; Buening, Hildegard; Hallek, Michael; King, Susan B S
2006-05-01
The modulated expression of MHC class I on tumour tissue is well documented. Although the effect of MHC class I expression on the tumorigenicity and immunogenicity of MHC class I negative tumour cell lines has been rigorously studied, less is known about the validity of gene transfer and selection in cell lines with a mixed MHC class I phenotype. To address this issue we identified a C26 cell subline that consists of distinct populations of MHC class I (H-2D/K) positive and negative cells. Transient transfection experiments using liposome-based transfer showed a lower transgene expression in MHC class I negative cells. In addition, MHC class I negative cells were more sensitive to antibiotic selection. This led to the generation of fully MHC class I positive cell lines. In contrast to C26 cells, all transfectants were rejected in vivo and induced protection against the parental tumour cells in rechallenge experiments. Tumour cell specificity of the immune response was demonstrated in in vitro cytokine secretion and cytotoxicity assays. Transfectants expressing CD40 ligand and hygromycin phosphotransferase were not more immunogenic than cells expressing hygromycin resistance alone. We suggest that the MHC class I positive phenotype of the C26 transfectants had a bearing on their immunogenicity, because selected MHC class I positive cells were more immunogenic than parental C26 cells and could induce specific anti-tumour immune responses. These data demonstrate that the generation of tumour cell transfectants can lead to the selection of subpopulations that show an altered phenotype compared to the parental cell line and display altered immunogenicity independent of selection marker genes or other immune modulatory genes. Our results show the importance of monitoring gene transfer in the whole tumour cell population, especially for the evaluation of in vivo therapies targeted to heterogeneous tumour cell populations.
Paternity and Nested-within-Family Marker Assisted Selection in Space Planted Red Clover Nurseries
USDA-ARS?s Scientific Manuscript database
Presented is a cost effective marker assisted selection methodology that utilizes individual plant phenotypes, seed production based knowledge of maternity, molecular marker determined paternity, and nested within halfsib family linkage relationships. Combining all above listed components, selection...
Ogino, Shuji; Kawasaki, Takako; Kirkner, Gregory J; Ohnishi, Mutsuko; Fuchs, Charles S
2007-05-02
The CpG island methylator phenotype (CIMP) with widespread promoter methylation is a distinct epigenetic phenotype in colorectal cancer, associated with microsatellite instability-high (MSI-high) and BRAF mutations. 18q loss of heterozygosity (LOH) commonly present in colorectal cancer with chromosomal instability (CIN) is associated with global hypomethylation in tumor cell. A recent study has shown an inverse correlation between CIN and CIMP (determined by MINTs, p16, p14 and MLH1 methylation) in colorectal cancer. However, no study has examined 18q LOH in relation to CIMP-high, CIMP-low (less extensive promoter methylation) and CIMP-0 (CIMP-negative), determined by quantitative DNA methylation analysis. Utilizing MethyLight technology (real-time PCR), we quantified DNA methylation in 8 CIMP-specific promoters {CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1} in 758 non-MSI-high colorectal cancers obtained from two large prospective cohorts. Using four 18q microsatellite markers (D18S55, D18S56, D18S67 and D18S487) and stringent criteria for 18q LOH, we selected 374 tumors (236 LOH-positive tumors with > or = 2 markers showing LOH; and 138 LOH-negative tumors with > or = 3 informative markers and no LOH). CIMP-0 (0/8 methylated promoters) was significantly more common in 18q LOH-positive tumors (59% = 139/236, p = 0.002) than 18q LOH-negative tumors (44% = 61/138), while CIMP-low/high (1/8-8/8 methylated promoters) was significantly more common (56%) in 18q LOH-negative tumors than 18q LOH-positive tumors (41%). These relations persisted after stratification by sex, location, or the status of MSI, p53 expression (by immunohistochemistry), or KRAS/BRAF mutation. 18q LOH is correlated positively with CIMP-0 and inversely with CIMP-low and CIMP-high. Our findings provide supporting evidence for relationship between CIMP-0 and 18q LOH as well as a molecular difference between CIMP-0 and CIMP-low in colorectal cancer.
USDA-ARS?s Scientific Manuscript database
Genomic selection (GS) simultaneously incorporates dense SNP marker genotypes with phenotypic data from related animals to predict animal-specific genomic breeding value (GEBV), which circumvents the need to measure the disease phenotype in potential breeders. Marker assisted selection (MAS) involv...
Poliovirus RNA recombination: mechanistic studies in the absence of selection.
Jarvis, T C; Kirkegaard, K
1992-01-01
Direct and quantitative detection of recombinant RNA molecules by polymerase chain reaction (PCR) provides a novel method for studying recombination in RNA viruses without selection for viable progeny. The parental poliovirus strains used in this study contained polymorphic marker loci approximately 600 bases apart; both exhibited wild-type growth characteristics. We established conditions under which the amount of PCR product was linearly proportional to the amount of input template, and the reproducibility was high. Recombinant progeny were predominantly homologous and arose at frequencies up to 2 x 10(-3). Recombination events increased in frequency throughout replication, indicating that there is no viral RNA sequestration or inhibition of recombination late in infection as proposed in earlier genetic studies. Previous studies have demonstrated that poliovirus recombination occurs by a copy-choice mechanism in which the viral polymerase switches templates during negative-strand synthesis. Varying the relative amount of input parental virus markedly altered reciprocal recombination frequencies. This, in conjunction with the kinetics data, indicated that acceptor template concentration is a determinant of template switching frequency. Since positive strands greatly outnumber negative strands throughout poliovirus infection, this would explain the bias toward recombination during negative-strand synthesis. Images PMID:1379178
Ipek, M; Ipek, A; Seker, M; Gul, M K
2015-03-27
The purpose of this research was to characterize an olive core collection using some agronomic characters and simple sequence repeat (SSR) markers and to determine SSR markers associated with the content of fatty acids in olive oil. SSR marker analysis demonstrated the presence of a high amount of genetic variation between the olive cultivars analyzed. A UPGMA dendrogram demonstrated that olive cultivars did not cluster on the basis of their geographic origin. Fatty acid components of olive oil in these cultivars were determined. The results also showed that there was a great amount of variation between the olive cultivars in terms of fatty acid composition. For example, oleic acid content ranged from 57.76 to 76.9% with standard deviation of 5.10%. Significant correlations between fatty acids of olive oil were observed. For instance, a very high negative correlation (-0.812) between oleic and linoleic acids was detected. A structured association analysis between the content of fatty acids in olive oil and SSR markers was performed. STRUCTURE analysis assigned olive cultivars to two gene pools (K = 2). Assignment of olive cultivars to these gene pools was not based on geographical origin. Association between fatty acid traits and SSR markers was evaluated using the general linear model of TASSEL. Significant associations were determined between five SSR markers and stearic, oleic, linoleic, and linolenic acids of olive oil. Very high associations (P < 0.001) between ssrOeUA-DCA14 and stearic acid and between GAPU71B and oleic acid indicated that these markers could be used for marker-assisted selection in olive.
Isgren, Anniella; Sellgren, Carl; Ekman, Carl-Johan; Holmén-Larsson, Jessica; Blennow, Kaj; Zetterberg, Henrik; Jakobsson, Joel; Landén, Mikael
2017-10-01
Neuroimmune mechanisms have been linked to the pathophysiology of bipolar disorder based on studies of biomarkers in plasma, cerebrospinal fluid (CSF), and postmortem brain tissue. There are, however, no longitudinal studies investigating if CSF markers of neuroinflammation and neuronal injury predict clinical outcomes in patients with bipolar disorder. We have in previous studies found higher CSF concentrations of interleukin-8 (IL-8), monocyte chemoattractant protein 1 (MCP-1/CCL-2), chitinase-3-like protein 1 (CHI3L1/YKL-40), and neurofilament light chain (NF-L) in euthymic patients with bipolar disorder compared with controls. Here, we investigated the relationship of these CSF markers of neuroinflammation and neuronal injury with clinical outcomes in a prospective study. 77 patients with CSF analyzed at baseline were followed for 6-7years. Associations of baseline biomarkers with clinical outcomes (manic/hypomanic and depressive episodes, suicide attempts, psychotic symptoms, inpatient care, GAF score change) were investigated. Baseline MCP-1 concentrations were positively associated with manic/hypomanic episodes and inpatient care during follow-up. YKL-40 concentrations were negatively associated with manic/hypomanic episodes and with occurrence of psychotic symptoms. The prospective negative association between YKL-40 and manic/hypomanic episodes survived multiple testing correction. Concentrations of IL-8 and NF-L were not associated with clinical outcomes. High concentrations of these selected CSF markers of neuroinflammation and neuronal injury at baseline were not consistently associated with poor clinical outcomes in this prospective study. The assessed proteins may be involved in adaptive immune processes or reflect a state of vulnerability for bipolar disorder rather than being of predictive value for disease progression. Copyright © 2017 Elsevier Inc. All rights reserved.
Calder, Philip C; Boobis, Alan; Braun, Deborah; Champ, Claire L; Dye, Louise; Einöther, Suzanne; Greyling, Arno; Matthys, Christophe; Putz, Peter; Wopereis, Suzan; Woodside, Jayne V; Antoine, Jean-Michel
2017-06-01
The conduct of high-quality nutrition research requires the selection of appropriate markers as outcomes, for example as indicators of food or nutrient intake, nutritional status, health status or disease risk. Such selection requires detailed knowledge of the markers, and consideration of the factors that may influence their measurement, other than the effects of nutritional change. A framework to guide selection of markers within nutrition research studies would be a valuable tool for researchers. A multidisciplinary Expert Group set out to test criteria designed to aid the evaluation of candidate markers for their usefulness in nutrition research and subsequently to develop a scoring system for markers. The proposed criteria were tested using thirteen markers selected from a broad range of nutrition research fields. The result of this testing was a modified list of criteria and a template for evaluating a potential marker against the criteria. Subsequently, a semi-quantitative system for scoring a marker and an associated template were developed. This system will enable the evaluation and comparison of different candidate markers within the same field of nutrition research in order to identify their relative usefulness. The ranking criteria of proven, strong, medium or low are likely to vary according to research setting, research field and the type of tool used to assess the marker and therefore the considerations for scoring need to be determined in a setting-, field- and tool-specific manner. A database of such markers, their interpretation and range of possible values would be valuable to nutrition researchers.
Expectations Do Not Alter Early Sensory Processing during Perceptual Decision-Making.
Rungratsameetaweemana, Nuttida; Itthipuripat, Sirawaj; Salazar, Annalisa; Serences, John T
2018-06-13
Two factors play important roles in shaping perception: the allocation of selective attention to behaviorally relevant sensory features, and prior expectations about regularities in the environment. Signal detection theory proposes distinct roles of attention and expectation on decision-making such that attention modulates early sensory processing, whereas expectation influences the selection and execution of motor responses. Challenging this classic framework, recent studies suggest that expectations about sensory regularities enhance the encoding and accumulation of sensory evidence during decision-making. However, it is possible, that these findings reflect well documented attentional modulations in visual cortex. Here, we tested this framework in a group of male and female human participants by examining how expectations about stimulus features (orientation and color) and expectations about motor responses impacted electroencephalography (EEG) markers of early sensory processing and the accumulation of sensory evidence during decision-making (the early visual negative potential and the centro-parietal positive potential, respectively). We first demonstrate that these markers are sensitive to changes in the amount of sensory evidence in the display. Then we show, counter to recent findings, that neither marker is modulated by either feature or motor expectations, despite a robust effect of expectations on behavior. Instead, violating expectations about likely sensory features and motor responses impacts posterior alpha and frontal theta oscillations, signals thought to index overall processing time and cognitive conflict. These findings are inconsistent with recent theoretical accounts and suggest instead that expectations primarily influence decisions by modulating post-perceptual stages of information processing. SIGNIFICANCE STATEMENT Expectations about likely features or motor responses play an important role in shaping behavior. Classic theoretical frameworks posit that expectations modulate decision-making by biasing late stages of decision-making including the selection and execution of motor responses. In contrast, recent accounts suggest that expectations also modulate decisions by improving the quality of early sensory processing. However, these effects could instead reflect the influence of selective attention. Here we examine the effect of expectations about sensory features and motor responses on a set of electroencephalography (EEG) markers that index early sensory processing and later post-perceptual processing. Counter to recent empirical results, expectations have little effect on early sensory processing but instead modulate EEG markers of time-on-task and cognitive conflict. Copyright © 2018 the authors 0270-6474/18/385632-17$15.00/0.
Mapping QTL for popping expansion volume in popcorn with simple sequence repeat markers.
Lu, H-J; Bernardo, R; Ohm, H W
2003-02-01
Popping expansion volume is the most important quality trait in popcorn ( Zea mays L.), but its genetics is not well understood. The objectives of this study were to map quantitative trait loci (QTLs) responsible for popping expansion volume in a popcorn x dent corn cross, and to compare the predicted efficiencies of phenotypic selection, marker-based selection, and marker-assisted selection for popping expansion volume. Of 259 simple sequence repeat (SSR) primer pairs screened, 83 pairs were polymorphic between the H123 (dent corn) and AG19 (popcorn) parental inbreds. Popping test data were obtained for 160 S(1) families developed from the [AG19(H123 x AG19)] BC(1) population. The heritability ( h(2)) for popping expansion volume on an S(1) family mean basis was 0.73. The presence of the gametophyte factor Ga1(s) in popcorn complicates the analysis of popcorn x dent corn crosses. But, from a practical perspective, the linkage between a favorable QTL allele and Ga1(s) in popcorn will lead to selection for the favorable QTL allele. Four QTLs, on chromosomes 1S, 3S, 5S and 5L, jointly explained 45% of the phenotypic variation. Marker-based selection for popping expansion volume would require less time and work than phenotypic selection. But due to the high h(2) of popping expansion volume, marker-based selection was predicted to be only 92% as efficient as phenotypic selection. Marker-assisted selection, which comprises index selection on phenotypic and marker scores, was predicted to be 106% as efficient as phenotypic selection. Overall, our results suggest that phenotypic selection will remain the preferred method for selection in popcorn x dent corn crosses.
Recent patents on biosafety strategies of selectable marker genes in genetically modified crops.
Jiang, Yiming; Hu, Xiaoning; Huang, Haiying
2014-01-01
Genetically modified crops (GMCs) have been planted world wide since 1990s, but the potential insecurity of selectable marker genes raises the questions about GMC safety. Therefore, several researches have been conducted on marker gene safety issues and recently several patents have been issued on this subject. There are two main approaches to achieve this goal: seeking the biosafety selectable marker and eliminating these insecure marker genes after transformation. Results show that these two systems are quite effective. Recent patents on the two ways are discussed in this review.
Engineering more stable, selectable marker-free autoluminescent mycobacteria by one step.
Yang, Feng; Njire, Moses M; Liu, Jia; Wu, Tian; Wang, Bangxing; Liu, Tianzhou; Cao, Yuanyuan; Liu, Zhiyong; Wan, Junting; Tu, Zhengchao; Tan, Yaoju; Tan, Shouyong; Zhang, Tianyu
2015-01-01
In our previous study, we demonstrated that the use of the autoluminescent Mycobacterium tuberculosis as a reporter strain had the potential to drastically reduce the time, effort, animals and costs consumed in evaluation of the activities of drugs and vaccines in live mice. However, the strains were relatively unstable and lost reporter with time without selection. The kanamycin selection marker used wasn't the best choice as it provides resistance to amino glycosides which are an important class of second line drugs used in tuberculosis treatment. In addition, the marker could limit utility of the strains for screening of new potential drugs or evaluating drug combinations for tuberculosis treatment. Limited selection marker genes for mycobacterial genetic manipulation is a major drawback for such a marker-containing strain in many research fields. Therefore, selectable marker-free, more stable autoluminescent mycobacteria are highly needed. After trying several strategies, we created such mycobacterial strains successfully by using an integrative vector and removing both the resistance maker and integrase genes by Xer site-specific recombination in one step. The corresponding plasmid vectors developed in this study could be very convenient in constructing other selectable marker-free, more stable reporter mycobacteria with diverse applications.
NASA Astrophysics Data System (ADS)
Silversides, Katherine L.; Melkumyan, Arman
2017-03-01
Machine learning techniques such as Gaussian Processes can be used to identify stratigraphically important features in geophysical logs. The marker shales in the banded iron formation hosted iron ore deposits of the Hamersley Ranges, Western Australia, form distinctive signatures in the natural gamma logs. The identification of these marker shales is important for stratigraphic identification of unit boundaries for the geological modelling of the deposit. Machine learning techniques each have different unique properties that will impact the results. For Gaussian Processes (GPs), the output values are inclined towards the mean value, particularly when there is not sufficient information in the library. The impact that these inclinations have on the classification can vary depending on the parameter values selected by the user. Therefore, when applying machine learning techniques, care must be taken to fit the technique to the problem correctly. This study focuses on optimising the settings and choices for training a GPs system to identify a specific marker shale. We show that the final results converge even when different, but equally valid starting libraries are used for the training. To analyse the impact on feature identification, GP models were trained so that the output was inclined towards a positive, neutral or negative output. For this type of classification, the best results were when the pull was towards a negative output. We also show that the GP output can be adjusted by using a standard deviation coefficient that changes the balance between certainty and accuracy in the results.
Jiang, Y; Zhao, Y; Rodemann, B; Plieske, J; Kollers, S; Korzun, V; Ebmeyer, E; Argillier, O; Hinze, M; Ling, J; Röder, M S; Ganal, M W; Mette, M F; Reif, J C
2015-03-01
Genome-wide mapping approaches in diverse populations are powerful tools to unravel the genetic architecture of complex traits. The main goals of our study were to investigate the potential and limits to unravel the genetic architecture and to identify the factors determining the accuracy of prediction of the genotypic variation of Fusarium head blight (FHB) resistance in wheat (Triticum aestivum L.) based on data collected with a diverse panel of 372 European varieties. The wheat lines were phenotyped in multi-location field trials for FHB resistance and genotyped with 782 simple sequence repeat (SSR) markers, and 9k and 90k single-nucleotide polymorphism (SNP) arrays. We applied genome-wide association mapping in combination with fivefold cross-validations and observed surprisingly high accuracies of prediction for marker-assisted selection based on the detected quantitative trait loci (QTLs). Using a random sample of markers not selected for marker-trait associations revealed only a slight decrease in prediction accuracy compared with marker-based selection exploiting the QTL information. The same picture was confirmed in a simulation study, suggesting that relatedness is a main driver of the accuracy of prediction in marker-assisted selection of FHB resistance. When the accuracy of prediction of three genomic selection models was contrasted for the three marker data sets, no significant differences in accuracies among marker platforms and genomic selection models were observed. Marker density impacted the accuracy of prediction only marginally. Consequently, genomic selection of FHB resistance can be implemented most cost-efficiently based on low- to medium-density SNP arrays.
Yada, Benard; Brown-Guedira, Gina; Alajo, Agnes; Ssemakula, Gorrettie N; Owusu-Mensah, Eric; Carey, Edward E; Mwanga, Robert O M; Yencho, G Craig
2017-03-01
Molecular markers are needed for enhancing the development of elite sweetpotato ( Ipomoea batatas (L.) Lam) cultivars with a wide range of commercially important traits in sub-Saharan Africa. This study was conducted to estimate the heritability and determine trait correlations of storage root yield, dry matter, starch and β-carotene content in a cross between 'New Kawogo' × 'Beauregard'. The study was also conducted to identify simple sequence repeat (SSR) markers associated with these traits. A total of 287 progeny and the parents were evaluated for two seasons at three sites in Uganda and genotyped with 250 SSR markers. Broad sense heritability (H 2 ) for storage root yield, dry matter, starch and β-carotene content were 0.24, 0.68, 0.70 and 0.90, respectively. Storage root β-carotene content was negatively correlated with dry matter (r = -0.59, P < 0.001) and starch (r = -0.93, P < 0.001) content, while storage root yield was positively correlated with dry matter (r = 0.57, P = 0.029) and starch (r = 0.41, P = 0.008) content. Through logistic regression, a total of 12, 4, 6 and 8 SSR markers were associated with storage root yield, dry matter, starch and β-carotene content, respectively. The SSR markers used in this study may be useful for quantitative trait loci analysis and selection for these traits in future.
Yada, Benard; Brown-Guedira, Gina; Alajo, Agnes; Ssemakula, Gorrettie N.; Owusu-Mensah, Eric; Carey, Edward E.; Mwanga, Robert O.M.; Yencho, G. Craig
2017-01-01
Molecular markers are needed for enhancing the development of elite sweetpotato (Ipomoea batatas (L.) Lam) cultivars with a wide range of commercially important traits in sub-Saharan Africa. This study was conducted to estimate the heritability and determine trait correlations of storage root yield, dry matter, starch and β-carotene content in a cross between ‘New Kawogo’ × ‘Beauregard’. The study was also conducted to identify simple sequence repeat (SSR) markers associated with these traits. A total of 287 progeny and the parents were evaluated for two seasons at three sites in Uganda and genotyped with 250 SSR markers. Broad sense heritability (H2) for storage root yield, dry matter, starch and β-carotene content were 0.24, 0.68, 0.70 and 0.90, respectively. Storage root β-carotene content was negatively correlated with dry matter (r = −0.59, P < 0.001) and starch (r = −0.93, P < 0.001) content, while storage root yield was positively correlated with dry matter (r = 0.57, P = 0.029) and starch (r = 0.41, P = 0.008) content. Through logistic regression, a total of 12, 4, 6 and 8 SSR markers were associated with storage root yield, dry matter, starch and β-carotene content, respectively. The SSR markers used in this study may be useful for quantitative trait loci analysis and selection for these traits in future. PMID:28588391
Nankali, Saber; Miandoab, Payam Samadi; Baghizadeh, Amin
2016-01-01
In external‐beam radiotherapy, using external markers is one of the most reliable tools to predict tumor position, in clinical applications. The main challenge in this approach is tumor motion tracking with highest accuracy that depends heavily on external markers location, and this issue is the objective of this study. Four commercially available feature selection algorithms entitled 1) Correlation‐based Feature Selection, 2) Classifier, 3) Principal Components, and 4) Relief were proposed to find optimum location of external markers in combination with two “Genetic” and “Ranker” searching procedures. The performance of these algorithms has been evaluated using four‐dimensional extended cardiac‐torso anthropomorphic phantom. Six tumors in lung, three tumors in liver, and 49 points on the thorax surface were taken into account to simulate internal and external motions, respectively. The root mean square error of an adaptive neuro‐fuzzy inference system (ANFIS) as prediction model was considered as metric for quantitatively evaluating the performance of proposed feature selection algorithms. To do this, the thorax surface region was divided into nine smaller segments and predefined tumors motion was predicted by ANFIS using external motion data of given markers at each small segment, separately. Our comparative results showed that all feature selection algorithms can reasonably select specific external markers from those segments where the root mean square error of the ANFIS model is minimum. Moreover, the performance accuracy of proposed feature selection algorithms was compared, separately. For this, each tumor motion was predicted using motion data of those external markers selected by each feature selection algorithm. Duncan statistical test, followed by F‐test, on final results reflected that all proposed feature selection algorithms have the same performance accuracy for lung tumors. But for liver tumors, a correlation‐based feature selection algorithm, in combination with a genetic search algorithm, proved to yield best performance accuracy for selecting optimum markers. PACS numbers: 87.55.km, 87.56.Fc PMID:26894358
Nankali, Saber; Torshabi, Ahmad Esmaili; Miandoab, Payam Samadi; Baghizadeh, Amin
2016-01-08
In external-beam radiotherapy, using external markers is one of the most reliable tools to predict tumor position, in clinical applications. The main challenge in this approach is tumor motion tracking with highest accuracy that depends heavily on external markers location, and this issue is the objective of this study. Four commercially available feature selection algorithms entitled 1) Correlation-based Feature Selection, 2) Classifier, 3) Principal Components, and 4) Relief were proposed to find optimum location of external markers in combination with two "Genetic" and "Ranker" searching procedures. The performance of these algorithms has been evaluated using four-dimensional extended cardiac-torso anthropomorphic phantom. Six tumors in lung, three tumors in liver, and 49 points on the thorax surface were taken into account to simulate internal and external motions, respectively. The root mean square error of an adaptive neuro-fuzzy inference system (ANFIS) as prediction model was considered as metric for quantitatively evaluating the performance of proposed feature selection algorithms. To do this, the thorax surface region was divided into nine smaller segments and predefined tumors motion was predicted by ANFIS using external motion data of given markers at each small segment, separately. Our comparative results showed that all feature selection algorithms can reasonably select specific external markers from those segments where the root mean square error of the ANFIS model is minimum. Moreover, the performance accuracy of proposed feature selection algorithms was compared, separately. For this, each tumor motion was predicted using motion data of those external markers selected by each feature selection algorithm. Duncan statistical test, followed by F-test, on final results reflected that all proposed feature selection algorithms have the same performance accuracy for lung tumors. But for liver tumors, a correlation-based feature selection algorithm, in combination with a genetic search algorithm, proved to yield best performance accuracy for selecting optimum markers.
Imputation of unordered markers and the impact on genomic selection accuracy
USDA-ARS?s Scientific Manuscript database
Genomic selection, a breeding method that promises to accelerate rates of genetic gain, requires dense, genome-wide marker data. Genotyping-by-sequencing can generate a large number of de novo markers. However, without a reference genome, these markers are unordered and typically have a large propo...
USDA-ARS?s Scientific Manuscript database
Many methods have been proposed to incorporate molecular markers into breeding programs. Presented is a cost effective marker assisted selection (MAS) methodology that utilizes individual plant phenotypes, seed production-based knowledge of maternity, and molecular marker-determined paternity. Proge...
USDA-ARS?s Scientific Manuscript database
The utilization of DNA molecular markers in plant breeding to maximize selection response via marker assisted selection (MAS) and genomic selection (GS) has the potential to revolutionize plant breeding. A key factor affecting GS applicability is the choice of molecular marker platform. Genotypying-...
[A comparison study of hpt and bar as selection marker gene of transgenic rice].
Zhang, Chun-Yu; Li, Hong-Yu; Liu, Bin
2012-12-01
The decision of using selection marker is one of the key factors for success of plant genetic transformation and offspring screening. As two commonly used selection markers, hpt and bar genes are widely used in tissue culture-based rice transformation. To experimentally compare their performance, we investigated the efficiency of two transformation systems using Hygromycin and Bialaphos as the selection agents, respectively. The result indicated that the system using hpt gene as the selection marker saved 10 days and had double transformation efficiency and lower transgene copy number in comparison to the system using bar gene. Then, we assessed the feasibility of screening transgenic rice in the field by soaking the wild-type and transgenic seeds in a series of solutions containing step diluted hygromycin for two days. We targeted the suitable concentration for distinguishing the transgenic seeds from WT Kitaake seeds was 167 mg L(-1). However, the cost of screening by hygromycin is still much higher than that of Basta in field test. Therefore, this study experimentally demonstrated the advantages and disadvantages of the hpt and bar gene as the selection markers and thus provided a reference for choose of an appropriate selection marker according to the practical applications.
Fischer, Martin C; Foll, Matthieu; Heckel, Gerald; Excoffier, Laurent
2014-01-01
Genetic adaptation to different environmental conditions is expected to lead to large differences between populations at selected loci, thus providing a signature of positive selection. Whereas balancing selection can maintain polymorphisms over long evolutionary periods and even geographic scale, thus leads to low levels of divergence between populations at selected loci. However, little is known about the relative importance of these two selective forces in shaping genomic diversity, partly due to difficulties in recognizing balancing selection in species showing low levels of differentiation. Here we address this problem by studying genomic diversity in the European common vole (Microtus arvalis) presenting high levels of differentiation between populations (average F ST = 0.31). We studied 3,839 Amplified Fragment Length Polymorphism (AFLP) markers genotyped in 444 individuals from 21 populations distributed across the European continent and hence over different environmental conditions. Our statistical approach to detect markers under selection is based on a Bayesian method specifically developed for AFLP markers, which treats AFLPs as a nearly codominant marker system, and therefore has increased power to detect selection. The high number of screened populations allowed us to detect the signature of balancing selection across a large geographic area. We detected 33 markers potentially under balancing selection, hence strong evidence of stabilizing selection in 21 populations across Europe. However, our analyses identified four-times more markers (138) being under positive selection, and geographical patterns suggest that some of these markers are probably associated with alpine regions, which seem to have environmental conditions that favour adaptation. We conclude that despite favourable conditions in this study for the detection of balancing selection, this evolutionary force seems to play a relatively minor role in shaping the genomic diversity of the common vole, which is more influenced by positive selection and neutral processes like drift and demographic history.
The not face: A grammaticalization of facial expressions of emotion.
Benitez-Quiroz, C Fabian; Wilbur, Ronnie B; Martinez, Aleix M
2016-05-01
Facial expressions of emotion are thought to have evolved from the development of facial muscles used in sensory regulation and later adapted to express moral judgment. Negative moral judgment includes the expressions of anger, disgust and contempt. Here, we study the hypothesis that these facial expressions of negative moral judgment have further evolved into a facial expression of negation regularly used as a grammatical marker in human language. Specifically, we show that people from different cultures expressing negation use the same facial muscles as those employed to express negative moral judgment. We then show that this nonverbal signal is used as a co-articulator in speech and that, in American Sign Language, it has been grammaticalized as a non-manual marker. Furthermore, this facial expression of negation exhibits the theta oscillation (3-8 Hz) universally seen in syllable and mouthing production in speech and signing. These results provide evidence for the hypothesis that some components of human language have evolved from facial expressions of emotion, and suggest an evolutionary route for the emergence of grammatical markers. Copyright © 2016 Elsevier B.V. All rights reserved.
The Not Face: A grammaticalization of facial expressions of emotion
Benitez-Quiroz, C. Fabian; Wilbur, Ronnie B.; Martinez, Aleix M.
2016-01-01
Facial expressions of emotion are thought to have evolved from the development of facial muscles used in sensory regulation and later adapted to express moral judgment. Negative moral judgment includes the expressions of anger, disgust and contempt. Here, we study the hypothesis that these facial expressions of negative moral judgment have further evolved into a facial expression of negation regularly used as a grammatical marker in human language. Specifically, we show that people from different cultures expressing negation use the same facial muscles as those employed to express negative moral judgment. We then show that this nonverbal signal is used as a co-articulator in speech and that, in American Sign Language, it has been grammaticalized as a non-manual marker. Furthermore, this facial expression of negation exhibits the theta oscillation (3–8 Hz) universally seen in syllable and mouthing production in speech and signing. These results provide evidence for the hypothesis that some components of human language have evolved from facial expressions of emotion, and suggest an evolutionary route for the emergence of grammatical markers. PMID:26872248
Vitte, Franck; Fabiani, Bettina; Bénet, Claire; Dalac, Sophie; Balme, Brigitte; Delattre, Claire; Vergier, Béatrice; Beylot-Barry, Marie; Vignon-Pennamen, Dominique; Ortonne, Nicolas; Algros, Marie Paule; Carlotti, Agnès; Samaleire, Dimitri; Frouin, Eric; Levy, Anne; Laroche, Liliane; Theate, Ivan; Monnien, Franck; Mugneret, Francine; Petrella, Tony
2012-09-01
Chronic myelomonocytic leukemia (CMML) is a rare clonal hematopoietic disorder that can also involve the skin. The histopathology of these skin lesions is not clearly defined, and few data are available in the literature. To better understand tumoral skin involvements in CMML we carried out an extensive, retrospective clinicopathologic study of 42 cases selected from the database of the French Study Group of Cutaneous Lymphomas. On the basis of clinical data, morphology, and phenotype we identified 4 clinicopathologic profiles representing 4 distinct groups. The first group comprised myelomonocytic cell tumors (n=18), exhibiting a proliferation of granulocytic or monocytic blast cells, which were CD68 and/or MPO positive but negative for dendritic cell markers. The second group comprised mature plasmacytoid dendritic cell tumors (n=16), denoted by a proliferation of mature plasmacytoid dendritic cells, which were CD123, TCL1, and CD303 positive but CD56, CD1a, and S100 negative. The third group comprised blastic plasmacytoid dendritic cell tumors (n=4), characterized by a proliferation of monomorphous medium-sized blast cells, which were CD4, CD56, CD123, TCL1 positive but CD1a and S100 negative. The fourth group consisted of a putatively novel category of tumor that we named blastic indeterminate dendritic cell tumors (n=4), distinguished by a proliferation of large blast cells that not only exhibited monocytic markers but also the dendritic markers CD1a and S100. These 4 groups showed distinctive outcomes. Finally, we showed, by fluorescence in situ hybridization analysis, a clonal link between bone marrow disease and skin lesions in 4 patients. Herein, we have described a novel scheme for pathologists and physicians to handle specific lesions in CMML, which correspond to a spectrum of myelomonocytic and dendritic cell proliferations with different outcomes. A minimal panel of immunohistochemical markers including CD68, CD1a, S100, Langerin, and CD123 is necessary to make the correct classification in this spectrum of cutaneous CMML tumors, in which dendritic cell lineage plays an important role.
Optimal marker-assisted selection to increase the effective size of small populations.
Wang, J
2001-02-01
An approach to the optimal utilization of marker and pedigree information in minimizing the rates of inbreeding and genetic drift at the average locus of the genome (not just the marked loci) in a small diploid population is proposed, and its efficiency is investigated by stochastic simulations. The approach is based on estimating the expected pedigree of each chromosome by using marker and individual pedigree information and minimizing the average coancestry of selected chromosomes by quadratic integer programming. It is shown that the approach is much more effective and much less computer demanding in implementation than previous ones. For pigs with 10 offspring per mother genotyped for two markers (each with four alleles at equal initial frequency) per chromosome of 100 cM, the approach can increase the average effective size for the whole genome by approximately 40 and 55% if mating ratios (the number of females mated with a male) are 3 and 12, respectively, compared with the corresponding values obtained by optimizing between-family selection using pedigree information only. The efficiency of the marker-assisted selection method increases with increasing amount of marker information (number of markers per chromosome, heterozygosity per marker) and family size, but decreases with increasing genome size. For less prolific species, the approach is still effective if the mating ratio is large so that a high marker-assisted selection pressure on the rarer sex can be maintained.
Endocytosis and interaction of poly (amidoamine) dendrimers with Caco-2 cells.
Kitchens, Kelly M; Foraker, Amy B; Kolhatkar, Rohit B; Swaan, Peter W; Ghandehari, Hamidreza
2007-11-01
To investigate the internalization and subcellular trafficking of fluorescently labeled poly (amidoamine) (PAMAM) dendrimers in intestinal cell monolayers. PAMAM dendrimers with positive or negative surface charge were conjugated to fluorescein isothiocyanate (FITC) and visualized for colocalization with endocytosis markers using confocal microscopy. Effect of concentration, generation and charge on the morphology of microvilli was observed using transmission electron microscopy. Both cationic and anionic PAMAM dendrimers internalized within 20 min, and differentially colocalized with endocytosis markers clathrin, EEA-1, and LAMP-1. Transmission electron microscopy analysis showed a concentration-, generation- and surface charge-dependent effect on microvilli morphology. These studies provide visual evidence that endocytic mechanism(s) contribute to the internalization and subcellular trafficking of PAMAM dendrimers across the intestinal cells, and that appropriate selection of PAMAM dendrimers based on surface charge, concentration and generation number allows the application of these polymers for oral drug delivery.
Bellassen, Virginie; Iglói, Kinga; de Souza, Leonardo Cruz; Dubois, Bruno; Rondi-Reig, Laure
2012-02-08
Episodic memory impairment is a hallmark for early diagnosis of Alzheimer's disease. Most actual tests used to diagnose Alzheimer's disease do not assess the spatiotemporal properties of episodic memory and lead to false-positive or -negative diagnosis. We used a newly developed, nonverbal navigation test for Human, based on the objective experimental testing of a spatiotemporal experience, to differentially Alzheimer's disease at the mild stage (N = 16 patients) from frontotemporal lobar degeneration (N = 11 patients) and normal aging (N = 24 subjects). Comparing navigation parameters and standard neuropsychological tests, temporal order memory appeared to have the highest predictive power for mild Alzheimer's disease diagnosis versus frontotemporal lobar degeneration and normal aging. This test was also nonredundant with classical neuropsychological tests. As a conclusion, our results suggest that temporal order memory tested in a spatial navigation task may provide a selective behavioral marker of Alzheimer's disease.
USDA-ARS?s Scientific Manuscript database
Genetic marker effects and type of inheritance are estimated with poor precision when minor marker allele frequencies are low. A stable composite population (MARC II) was subjected to marker assisted selection for two years to equalize CSN1S1 and TG genetic marker frequencies to evaluate the epista...
El Demellawy, Dina; Nasr, Ahmed; Alowami, Salem
2008-01-01
Papillary carcinoma of the thyroid (PTC) is the commonest thyroid cancer. In the recent decades an obvious increase in the incidence of PTC has occurred. The pathological diagnosis of PTC is usually an easy diagnosis in the majority of cases. However since the introduction of follicular variant of PTC and the wide threshold range in interpretation of the clearly set pathological criteria for diagnosis of PTC, between pathologists including experts, the diagnosis in some cases became quite difficult. Unfortunately some cases are unjustifiably over-called as follicular variant of PTC as a result of the wide inter observable variability between pathologists, including thyroid pathologists. Ancillary studies such as immmunohistochemistry may be helpful, but till now there is no 100% consistent marker(s), that distinct between PTC and other follicular thyroid lesions and tumors. We assessed expression of antibodies against CD56, CK19, P63 and E-Cadherin in PTC and other follicular thyroid lesions and neoplasms. A total of 175 cases were studied. The neoplastic cases included 75 carcinomas (72 papillary, 2 follicular, 1 Hurthle cell) and 35 adenomas (32 follicular and 3 Hurthle cell). The non-neoplastic thyroids included 65 cases, (25 nodular hyperplasia, 5 thyrotoxic hyperplasia (Grave's disease), 19 lymphocytic thyroiditis and 6 Hashimoto's thyroiditis). All cases were evaluated by immunohistochemistry for the expression of the above mentioned markers. The markers' patterns and intensities of staining were scored. Positive expression of the markers equal or >10% of the follicular epithelium within the tumor or lesional cells was considered positive. An expression of <10% was considered to be negative. Our results showed CD56 positive in all the lesions and tumors except for PTC in all cases (100%). CD56 was negative in all PTC cases (100%). CK 19 showed positive expression in PTC accounting for 85% of cases and in 26% of non PTC lesions/tumors. P63 showed selective focal positivity in PTC cases, in contrast to other non PTC lesions/tumors. P63 expression was in 70% of cases of PTC and was consistently absent in all the non PTC cases. E-Cadherin showed consistent non discriminatory expression in all cases included in the study. We concluded that a panel consisted of CD56, CK19 and P63 is of value in distinction of PTC from other thyroid follicular lesion. P63 is a specific but less sensitive marker for PTC than CK19. CD56 is more specific and sensitive marker than CK19, however it is a negative rather than a positive marker for PTC. E-Cadherin is of no value in the diagnosis of thyroid follicular lesions/tumors. We recommend application of a panel composed of CK19, P63 and CD56 by a group of expert thyroid pathologists on a large series of follicular malignant thyroid neoplasms of uncertain malignant. PMID:18254952
EgoNet: identification of human disease ego-network modules
2014-01-01
Background Mining novel biomarkers from gene expression profiles for accurate disease classification is challenging due to small sample size and high noise in gene expression measurements. Several studies have proposed integrated analyses of microarray data and protein-protein interaction (PPI) networks to find diagnostic subnetwork markers. However, the neighborhood relationship among network member genes has not been fully considered by those methods, leaving many potential gene markers unidentified. The main idea of this study is to take full advantage of the biological observation that genes associated with the same or similar diseases commonly reside in the same neighborhood of molecular networks. Results We present EgoNet, a novel method based on egocentric network-analysis techniques, to exhaustively search and prioritize disease subnetworks and gene markers from a large-scale biological network. When applied to a triple-negative breast cancer (TNBC) microarray dataset, the top selected modules contain both known gene markers in TNBC and novel candidates, such as RAD51 and DOK1, which play a central role in their respective ego-networks by connecting many differentially expressed genes. Conclusions Our results suggest that EgoNet, which is based on the ego network concept, allows the identification of novel biomarkers and provides a deeper understanding of their roles in complex diseases. PMID:24773628
Alizadeh, Arash; Braber, Saskia; Akbari, Peyman; Garssen, Johan; Fink-Gremmels, Johanna
2015-01-01
Deoxynivalenol (DON) is one of the major mycotoxins produced by Fusarium fungi, and exposure to this mycotoxin requires an assessment of the potential adverse effects, even at low toxin levels. The aim of this study was to investigate the effects of a short-term, low-dose DON exposure on various gut health parameters in pigs. Piglets received a commercial feed or the same feed contaminated with DON (0.9 mg/kg feed) for 10 days, and two hours after a DON bolus (0.28 mg/kg BW), weight gain was determined and samples of different segments of the intestine were collected. Even the selected low dose of DON in the diet negatively affected weight gain and induced histomorphological alterations in the duodenum and jejunum. The mRNA expression of different tight junction (TJ) proteins, especially occludin, of inflammatory markers, like interleukin-1 beta and interleukin-10 and the oxidative stress marker heme-oxigenase1, were affected along the intestine by low levels of DON in the diet. Taken together, our results indicate that even after low-level exposure to DON, which has been generally considered as acceptable in animal feeds, clinically-relevant changes are measurable in markers of gut health and integrity. PMID:26067367
Mago, Rohit; Verlin, Dawn; Zhang, Peng; Bansal, Urmil; Bariana, Harbans; Jin, Yue; Ellis, Jeffrey; Hoxha, Sami; Dundas, Ian
2013-12-01
Wheat- Aegilops speltoides recombinants carrying stem rust resistance genes Sr32 and SrAes1t effective against Ug99 and PCR markers for marker-assisted selection. Wild relatives of wheat are important resources for new rust resistance genes but underutilized because the valuable resistances are often linked to negative traits that prevent deployment of these genes in commercial wheats. Here, we report ph1b-induced recombinants with reduced alien chromatin derived from E.R. Sears' wheat-Aegilops speltoides 2D-2S#1 translocation line C82.2, which carries the widely effective stem rust resistance gene Sr32. Infection type assessments of the recombinants showed that the original translocation in fact carries two stem rust resistance genes, Sr32 on the short arm and a previously undescribed gene SrAes1t on the long arm of chromosome 2S#1. Recombinants with substantially shortened alien chromatin were produced for both genes, which confer resistance to stem rust races in the TTKSK (Ug99) lineage and representative races of all Australian stem rust lineages. Selected recombinants were back crossed into adapted Australian cultivars and PCR markers were developed to facilitate the incorporation of these genes into future wheat varieties. Our recombinants and those from several other labs now show that Sr32, Sr39, and SrAes7t on the short arm and Sr47 and SrAes1t on the long arm of 2S#1 form two linkage groups and at present no rust races are described that can distinguish these resistance specificities.
Ghatak, Arindam; Chaturvedi, Palak; Weckwerth, Wolfram
2017-01-01
Sustainable crop production is the major challenge in the current global climate change scenario. Drought stress is one of the most critical abiotic factors which negatively impact crop productivity. In recent years, knowledge about molecular regulation has been generated to understand drought stress responses. For example, information obtained by transcriptome analysis has enhanced our knowledge and facilitated the identification of candidate genes which can be utilized for plant breeding. On the other hand, it becomes more and more evident that the translational and post-translational machinery plays a major role in stress adaptation, especially for immediate molecular processes during stress adaptation. Therefore, it is essential to measure protein levels and post-translational protein modifications to reveal information about stress inducible signal perception and transduction, translational activity and induced protein levels. This information cannot be revealed by genomic or transcriptomic analysis. Eventually, these processes will provide more direct insight into stress perception then genetic markers and might build a complementary basis for future marker-assisted selection of drought resistance. In this review, we survey the role of proteomic studies to illustrate their applications in crop stress adaptation analysis with respect to productivity. Cereal crops such as wheat, rice, maize, barley, sorghum and pearl millet are discussed in detail. We provide a comprehensive and comparative overview of all detected protein changes involved in drought stress in these crops and have summarized existing knowledge into a proposed scheme of drought response. Based on a recent proteome study of pearl millet under drought stress we compare our findings with wheat proteomes and another recent study which defined genetic marker in pearl millet. PMID:28626463
Stepp, Stephanie D.; Scott, Lori N.; Jones, Neil P.; Whalen, Diana J.; Hipwell, Alison E.
2015-01-01
Negative emotionality is a distinguishing feature of borderline personality disorder (BPD). However, this person-level characteristic has not been examined as a marker of vulnerability in the development of this disorder. The current study utilized a multi-method approach to examine the interplay between negative emotional reactivity and cumulative exposure to family adversity on the development of BPD symptoms across three years (ages 16–18) in a diverse, at-risk sample of adolescent girls (N=113). A latent variable of negative emotional reactivity was created from multiple assessments at age 16: (1) self-report, (2) emotion ratings to stressors from ecological assessments across one week, and (3) observer-rated negative affectivity during a mother-daughter conflict discussion task. Exposure to family adversity was measured cumulatively between ages 5 and 16 from annual assessments of family poverty, single parent household, and difficult life circumstances. Results from latent growth curve models demonstrated a significant interaction between negative emotional reactivity and family adversity, such that exposure to adversity strengthened the association between negative emotional reactivity and BPD symptoms. Additionally, family adversity predicted increasing BPD symptoms during late adolescence. These findings highlight negative emotional reactivity as a marker of vulnerability that ultimately increases risk for the development of BPD symptoms. PMID:25925083
Stepp, Stephanie D; Scott, Lori N; Jones, Neil P; Whalen, Diana J; Hipwell, Alison E
2016-02-01
Negative emotionality is a distinguishing feature of borderline personality disorder (BPD). However, this person-level characteristic has not been examined as a marker of vulnerability in the development of this disorder. The current study utilized a multimethod approach to examine the interplay between negative emotional reactivity and cumulative exposure to family adversity on the development of BPD symptoms across 3 years (ages 16-18) in a diverse, at-risk sample of adolescent girls (N = 113). A latent variable of negative emotional reactivity was created from multiple assessments at age 16: self-report, emotion ratings to stressors from ecological assessments across 1 week, and observer-rated negative affectivity during a mother-daughter conflict discussion task. Exposure to family adversity was measured cumulatively between ages 5 and 16 from annual assessments of family poverty, single parent household, and difficult life circumstances. The results from latent growth curve models demonstrated a significant interaction between negative emotional reactivity and family adversity, such that exposure to adversity strengthened the association between negative emotional reactivity and BPD symptoms. In addition, family adversity predicted increasing BPD symptoms during late adolescence. These findings highlight negative emotional reactivity as a marker of vulnerability that ultimately increases risk for the development of BPD symptoms.
The influence of executive capacity on selective attention and subsequent processing
Daffner, Kirk R.; Tarbi, Elise C.; Haring, Anna E.; Zhuravleva, Tatyana Y.; Sun, Xue; Rentz, Dorene M.; Holcomb, Phillip J.
2012-01-01
Recent investigations that suggest selective attention (SA) is dependent on top-down control mechanisms lead to the expectation that individuals with high executive capacity (EC) would exhibit more robust neural indices of SA. This prediction was tested by using event-related potentials (ERPs) to examine differences in markers of information processing across 25 subjects divided into two groups based on high vs. average EC, as defined by neuropsychological test scores. Subjects performed an experimental task requiring SA to a specified color. In contrast to expectation, individuals with high and average EC did not differ in the size of ERP indices of SA: the anterior Selection Positivity (SP) and posterior Selection Negativity (SN). However, there were substantial differences between groups in markers of subsequent processing, including the anterior N2 (a measure of attentional control) and the P3a (an index of the orienting of attention). EC predicted speed of processing at both early and late attentional stages. Individuals with lower EC exhibited prolonged SN, P3a, and P3b latencies. However, the delays in carrying out SA operations did not account for subsequent delays in decision making, or explain excessive orienting and reduced attentional control mechanisms in response to stimuli that should have been ignored. SN latency, P3 latency, and the size of the anterior N2 made independent contributions to the variance of EC. In summary, our findings suggest that current views regarding the relationship between top-down control mechanisms and SA may need refinement. PMID:22701415
Akkurt, M; Çakır, A; Shidfar, M; Çelikkol, B P; Söylemezoğlu, G
2012-08-13
We used molecular markers associated with seedlessness in grapes, namely SCC8, SCF27 and VMC7f2, to improve the efficiency of seedless grapevine breeding via marker assisted selection (MAS). DNA from 372 F₁ hybrid progeny from the cross between seeded "Alphonse Lavallée" and seedless "Sultani" was amplified by PCR using three markers. After digestion of SCC8 marker amplification products by restriction enzyme BgIII, 40 individuals showed homozygous SCC8+/SCC8+ alleles at the seed development inhibitor (SdI) locus. DNA from 80 of the progeny amplified with the SCF27 marker produced bands; 174 individuals had 198-bp alleles of the VMC7f2 marker associated with seedlessness. In the second year, based on MAS, 183 F₁ hybrids were designated as seedless grapevine candidates because they were positive for a minimum of one marker. Twenty individuals were selected as genetic resources for future studies on seedless grapevine breeding because they carried alleles for the three markers associated with seedlessness. The VMC7f2 SSR marker was identified as the marker most associated with seedlessness.
Urbanová, Jana; Rypáčková, Blanka; Kučera, Petr; Anděl, Michal; Heneberg, Petr
2013-01-01
It was recently suggested that routine islet cell autoantibody testing should be performed to discriminate maturity-onset diabetes of the young (MODY) from type 1 diabetes mellitus (T1DM). This is the first report ever to describe the familial manifestation of T1DM autoimmunity in nonobese HNF1A-MODY subjects and the presence of islet antigen-2 (IA-2) antibodies in MODY subjects. Three nonobese subjects in an age range of 14-35 years were diagnosed with HNF1A-MODY (p. Arg159Gln mutation). All the tested subjects had detectable (but varying) levels of islet cell autoantibodies (i.e., antibodies against glutamate decarboxylase or IA-2) in the absence of other T1DM characteristics. They displayed long-term expression of intermediate fasting C-peptide levels, ketoacidosis was absent even in periods of spontaneous insulin withdrawal, and full dependence on externally administered insulin was not detected in any of them although better glycemic control was achieved when insulin was supplemented. The course of the disease was similar to that of the autoantibody-negative HNF1A-MODY subjects. The case questions the selectivity of autoantibodies as a marker of T1DM or late-onset autoimmune diabetes of adulthood (LADA) over MODY and challenges the use of autoantibodies as a universal negative marker of MODY in an effort to decrease the cost of health care, as it may eventually lead to the wrong diagnosis and thus to the incorrect treatment. Further research should involve examination of the autoantibody titers and prevalence in large and geographically diverse cohorts of MODY subjects selected for genetic testing (regardless of their autoantibody titers) as well as determination of the islet cell autoantibody kinetics in the course of MODY onset and progression. Copyright © 2013 S. Karger AG, Basel.
Panoz-Brown, Danielle; Carey, Lawrence M; Smith, Alexandra E; Gentry, Meredith; Sluka, Christina M; Corbin, Hannah E; Wu, Jie-En; Hohmann, Andrea G; Crystal, Jonathon D
2017-10-01
Chemotherapy is widely used to treat patients with systemic cancer. The efficacy of cancer therapies is frequently undermined by adverse side effects that have a negative impact on the quality of life of cancer survivors. Cancer patients who receive chemotherapy often experience chemotherapy-induced cognitive impairment across a variety of domains including memory, learning, and attention. In the current study, the impact of paclitaxel, a taxane derived chemotherapeutic agent, on episodic memory, prior learning, new learning, and reversal learning were evaluated in rats. Neurogenesis was quantified post-treatment in the dentate gyrus of the same rats using immunostaining for 5-Bromo-2'-deoxyuridine (BrdU) and Ki67. Paclitaxel treatment selectively impaired reversal learning while sparing episodic memory, prior learning, and new learning. Furthermore, paclitaxel-treated rats showed decreases in markers of hippocampal cell proliferation, as measured by markers of cell proliferation assessed using immunostaining for Ki67 and BrdU. This work highlights the importance of using multiple measures of learning and memory to identify the pattern of impaired and spared aspects of chemotherapy-induced cognitive impairment. Copyright © 2017 Elsevier Inc. All rights reserved.
Efficient Breeding by Genomic Mating.
Akdemir, Deniz; Sánchez, Julio I
2016-01-01
Selection in breeding programs can be done by using phenotypes (phenotypic selection), pedigree relationship (breeding value selection) or molecular markers (marker assisted selection or genomic selection). All these methods are based on truncation selection, focusing on the best performance of parents before mating. In this article we proposed an approach to breeding, named genomic mating, which focuses on mating instead of truncation selection. Genomic mating uses information in a similar fashion to genomic selection but includes information on complementation of parents to be mated. Following the efficiency frontier surface, genomic mating uses concepts of estimated breeding values, risk (usefulness) and coefficient of ancestry to optimize mating between parents. We used a genetic algorithm to find solutions to this optimization problem and the results from our simulations comparing genomic selection, phenotypic selection and the mating approach indicate that current approach for breeding complex traits is more favorable than phenotypic and genomic selection. Genomic mating is similar to genomic selection in terms of estimating marker effects, but in genomic mating the genetic information and the estimated marker effects are used to decide which genotypes should be crossed to obtain the next breeding population.
Yang, Huaan; Jian, Jianbo; Li, Xuan; Renshaw, Daniel; Clements, Jonathan; Sweetingham, Mark W; Tan, Cong; Li, Chengdao
2015-09-02
Molecular marker-assisted breeding provides an efficient tool to develop improved crop varieties. A major challenge for the broad application of markers in marker-assisted selection is that the marker phenotypes must match plant phenotypes in a wide range of breeding germplasm. In this study, we used the legume crop species Lupinus angustifolius (lupin) to demonstrate the utility of whole genome sequencing and re-sequencing on the development of diagnostic markers for molecular plant breeding. Nine lupin cultivars released in Australia from 1973 to 2007 were subjected to whole genome re-sequencing. The re-sequencing data together with the reference genome sequence data were used in marker development, which revealed 180,596 to 795,735 SNP markers from pairwise comparisons among the cultivars. A total of 207,887 markers were anchored on the lupin genetic linkage map. Marker mining obtained an average of 387 SNP markers and 87 InDel markers for each of the 24 genome sequence assembly scaffolds bearing markers linked to 11 genes of agronomic interest. Using the R gene PhtjR conferring resistance to phomopsis stem blight disease as a test case, we discovered 17 candidate diagnostic markers by genotyping and selecting markers on a genetic linkage map. A further 243 candidate diagnostic markers were discovered by marker mining on a scaffold bearing non-diagnostic markers linked to the PhtjR gene. Nine out from the ten tested candidate diagnostic markers were confirmed as truly diagnostic on a broad range of commercial cultivars. Markers developed using these strategies meet the requirements for broad application in molecular plant breeding. We demonstrated that low-cost genome sequencing and re-sequencing data were sufficient and very effective in the development of diagnostic markers for marker-assisted selection. The strategies used in this study may be applied to any trait or plant species. Whole genome sequencing and re-sequencing provides a powerful tool to overcome current limitations in molecular plant breeding, which will enable plant breeders to precisely pyramid favourable genes to develop super crop varieties to meet future food demands.
Effective Teaching in the Use of Pragmatic Markers for Chinese EFL Learners
ERIC Educational Resources Information Center
Li, Wang
2015-01-01
Research on teaching the use of pragmatic markers to L2 learners is a relatively new area and many aspects are still not addressed. It was assumed that negative pragmatic transfer, the limited linguistic input in the course-books that EFL learners are exposed to, and the negative influence of formal instruction were possible driving factors that…
Elias, W. P.; Uber, A. P.; Tomita, S. K.; Trabulsi, L. R.; Gomes, T. A. T.
2002-01-01
Enteroaggregative Escherichia coli (EAEC) is defined by the ability to produce aggregative adherence (AA) to cultured cells. We analysed 128 EAEC strains, isolated from children with and without diarrhoea, regarding the presence of 11 EAEC virulence genes. Seventy strains carried and 58 lacked the EAEC probe sequence; 17 probe positive and 31 probe negative strains showed variations in the AA pattern. All EAEC probe positive strains carried at least one EAEC marker; aspU (94.3%), irp2 (91.4%), and aggR (74.3%) were the most prevalent. Conversely, among the EAEC probe negative strains, 41.4% were devoid of any marker and astA predominated (44.8%). No significant statistical difference in the prevalence of any marker between cases and controls in both EAEC probe groups or AA variants was found. We suggest that the EAEC probe positive strains may have a higher pathogenic potential or alternatively, EAEC probe negative strains may harbour virulence factors as yet undescribed. PMID:12211596
Zhang, X J; Wang, L X; Chen, X X; Liu, Y L; Meng, R; Wang, Y J; Zhao, Z Y
2014-10-31
Pre-selection for fruit skin color at the seedling stage would be highly advantageous, with marker-assisted selection offering a potential method for apple pre-selection. A and MdMYB1 alleles are allele-specific DNA markers that are potentially associated with apple skin color, and co-segregate with the Rf and Rni loci, respectively. Here, we assessed the potential application of these 2 alleles for marker-assisted breeding across 30 diverse cultivars and 2 apple seedling progenies. The red skin color phenotype was usually associated with the MdMYB1-1 allele and A(1) allele, respectively, while the 2 molecular markers provided approximately 91% predictability in the 'Fuji' x 'Cripps Pink' and 'Fuji' x 'Gala' progenies. The results obtained from the 30 cultivars and 2 progenies were consistent for the 2 molecular markers. Hence, the results supported that Rf and Rni could be located in a gene cluster, or even correspond to alleles of the same gene. Our results are consistent with the hypothesis that red/yellow dimorphism is controlled by a monogenic system, with the presence of the red anthocyanin pigmentation being dominant. In addition, our results supported that the practical utilization of the 2 function markers to efficiently and accurately select red-skinned apple cultivars in apple scion breeding programs.
Manimaran, P; Ramkumar, G; Sakthivel, K; Sundaram, R M; Madhav, M S; Balachandran, S M
2011-01-01
Genetically modified crops are one of the prudent options for enhancing the production and productivity of crop plants by safeguarding from the losses due to biotic and abiotic stresses. Agrobacterium-mediated and biolistic transformation methods are used to develop transgenic crop plants in which selectable marker genes (SMG) are generally deployed to identify 'true' transformants. The commonly used SMG obtained from prokaryotic sources when employed in transgenic plants pose risks due to their lethal nature during selection process. In the recent past, some non-lethal SMGs have been identified and used for selection of transformants with increased precision and high selection efficiency. Considering the concerns related to bio-safety of the environment, it is desirable to remove the SMG in order to maximize the commercial success through wide adoption and public acceptance of genetically modified (GM) food crops. In this review, we examine the availability, and the suitability of wide range of non-lethal selection markers and elimination of SMG methods to develop marker-free transgenics for achieving global food security. As the strategies for marker-free plants are still in proof-of-concept stage, adaptation of new genomics tools for identification of novel non-lethal marker systems and its application for developing marker-free transgenics would further strengthen the crop improvement program. Copyright © 2011 Elsevier Inc. All rights reserved.
Darwish, Nader Ahmed; Khan, Raham Sher; Ntui, Valentine Otang; Nakamura, Ikuo; Mii, Masahiro
2014-03-01
Marker-free transgenic eggplants, exhibiting enhanced resistance to Alternaria solani , can be generated on plant growth regulators (PGRs)- and antibiotic-free MS medium employing the multi-auto-transformation (MAT) vector, pMAT21 - wasabi defensin , wherein isopentenyl transferase ( ipt ) gene is used as a positive selection marker. Use of the selection marker genes conferring antibiotic or herbicide resistance in transgenic plants has been considered a serious problem for environment and the public. Multi-auto-transformation (MAT) vector system has been one of the tools to excise the selection marker gene and produce marker-free transgenic plants. Ipt gene was used as a selection marker gene. Wasabi defensin gene, isolated from Wasabia japonica (a Japanese horseradish which has been a potential source of antimicrobial proteins), was used as a gene of interest. Wasabi defensin gene was cloned from the binary vector, pEKH-WD, to an ipt-type MAT vector, pMAT21, by gateway cloning technology and transferred to Agrobacterium tumefaciens strain EHA105. Infected cotyledon explants of eggplant were cultured on PGRs- and antibiotic-free MS medium. Extreme shooty phenotype/ipt shoots were produced by the explants infected with the pMAT21-wasabi defensin (WD). The same PGRs- and antibiotic-free MS medium was used in subcultures of the ipt shoots. Subsequently, morphologically normal shoots emerged from the Ipt shoots. Molecular analyses of genomic DNA from transgenic plants confirmed the integration of the WD gene and excision of the selection marker (ipt gene). Expression of the WD gene was confirmed by RT-PCR and Northern blot analyses. In vitro whole plant and detached leaf assay of the marker-free transgenic plants exhibited enhanced resistance against Alternaria solani.
Kharchenko, Maria S; Teslya, Petr N; Babaeva, Maria N; Zakataeva, Natalia P
2018-05-01
Bacillus subtilis pheS was genetically modified to obtain a counter-selection marker with high selection efficiency in Bacillus amyloliquefaciens. The application of the new replication-thermosensitive integrative vector pNZTM1, containing this marker, pheS BsT255S/A309G , with a two-step replacement recombination procedure provides an effective tool for the genetic engineering of industrially important Bacillus species. Copyright © 2018. Published by Elsevier B.V.
Interleukin-6 in cerebrospinal fluid as a biomarker of acute meningitis.
García-Hernández, Pablo; Prieto, Belén; Martínez-Morillo, Eduardo; Rodríguez, Verónica; Álvarez, Francisco V
2016-01-01
Microbiological culture of cerebrospinal fluid is the gold standard to differentiate between aseptic and bacterial meningitis, but this method has low sensitivity. A fast and reliable new marker would be of interest in clinical practice. Interleukin-6, secreted by T cells in response to meningeal pathogens and quickly delivered into cerebrospinal fluid, was evaluated as a marker of acute meningitis. A total of 150 cerebrospinal fluid samples were analysed by an electrochemiluminescence method, selected according to patient diagnosis: (a) bacterial meningitis confirmed by positive culture (n = 26); (b) bacterial meningitis with negative culture or not performed (n = 15); (c) viral meningitis confirmed by polymerase chain reaction or immunoglobulin G determination (n = 23); (d) viral meningitis with polymerase chain reaction negative or not performed (n = 42); and (e) controls (n = 44). Cerebrospinal fluid interleukin-6 concentration showed significant differences between all pathologic groups and the control group (P < 0.001). As a diagnostic tool for bacterial meningitis, interleukin-6 showed an area under the curve of 0.937 (95% confidence intervals: 0.895-0.978), significantly higher than those of classical biomarkers. An interleukin-6 cutoff of 1418 pg/mL showed 95.5% sensitivity and 77.5% specificity, whereas a value of 15,060 pg/mL showed 63.6% sensitivity and 96.7% specificity, for diagnosis of bacterial meningitis. Interleukin-6 measured by electrochemiluminescence method is a promising marker for early differentiation between aseptic and bacterial meningitis. More studies are needed to validate clinical implications for future practice in an emergency laboratory. © The Author(s) 2015.
Novel prognostic tissue markers in congestive heart failure.
Stone, James R
2015-01-01
Heart failure is a relatively common disorder associated with high morbidity, mortality, and economic burden. Better tools to predict outcomes for patients with heart failure could allow for better decision making concerning patient treatment and management and better utilization of health care resources. Endomyocardial biopsy offers a mechanism to pathologically diagnose specific diseases in patients with heart failure, but such biopsies can often be negative, with no specific diagnostic information. Novel tissue markers in endomyocardial biopsies have been identified that may be useful in assessing prognosis in heart failure patients. Such tissue markers include ubiquitin, Gremlin-1, cyclophilin A, and heterogeneous nuclear ribonucleoprotein C. In some cases, tissue markers have been found to be independent of and even superior to clinical indices and serum markers in predicting prognosis for heart failure patients. In some cases, these novel tissue markers appear to offer prognostic information even in the setting of an otherwise negative endomyocardial biopsy. Copyright © 2014 Elsevier Inc. All rights reserved.
Genomic Selection in Multi-environment Crop Trials.
Oakey, Helena; Cullis, Brian; Thompson, Robin; Comadran, Jordi; Halpin, Claire; Waugh, Robbie
2016-05-03
Genomic selection in crop breeding introduces modeling challenges not found in animal studies. These include the need to accommodate replicate plants for each line, consider spatial variation in field trials, address line by environment interactions, and capture nonadditive effects. Here, we propose a flexible single-stage genomic selection approach that resolves these issues. Our linear mixed model incorporates spatial variation through environment-specific terms, and also randomization-based design terms. It considers marker, and marker by environment interactions using ridge regression best linear unbiased prediction to extend genomic selection to multiple environments. Since the approach uses the raw data from line replicates, the line genetic variation is partitioned into marker and nonmarker residual genetic variation (i.e., additive and nonadditive effects). This results in a more precise estimate of marker genetic effects. Using barley height data from trials, in 2 different years, of up to 477 cultivars, we demonstrate that our new genomic selection model improves predictions compared to current models. Analyzing single trials revealed improvements in predictive ability of up to 5.7%. For the multiple environment trial (MET) model, combining both year trials improved predictive ability up to 11.4% compared to a single environment analysis. Benefits were significant even when fewer markers were used. Compared to a single-year standard model run with 3490 markers, our partitioned MET model achieved the same predictive ability using between 500 and 1000 markers depending on the trial. Our approach can be used to increase accuracy and confidence in the selection of the best lines for breeding and/or, to reduce costs by using fewer markers. Copyright © 2016 Oakey et al.
Nestin is expressed in HMB-45 negative melanoma cells in dermal parts of nodular melanoma.
Kanoh, Maho; Amoh, Yasuyuki; Tanabe, Kenichi; Maejima, Hideki; Takasu, Hiroshi; Katsuoka, Kensei
2010-06-01
Nestin, a marker of neural stem cells, is expressed in the stem cells of the mouse hair follicle. The nestin-expressing hair follicle stem cells can differentiate into neurons, glia, keratocytes, smooth muscle cells and melanocytes in vitro. These pluripotent nestin-expressing stem cells are keratin 15 (K15)-negative, suggesting that they are in a relatively undifferentiated state. Recent studies suggest that the epithelial stem cells are important in tumorigenesis, and nestin expression is thought to be important in tumorigenesis. In the present study, we examined the expression of the hair follicle and neural stem cell marker nestin, as well as S-100 and HMB-45, in melanoma. Nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in all five cases of amelanotic nodular melanomas. Moreover, nestin immunoreactivity was observed in the dermal parts in seven of 10 cases of melanotic nodular melanomas. Especially, nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in the dermal parts of all 10 cases of HMB-45-negative amelanotic and melanotic nodular melanomas. On the other hand, nestin expression was negative in 10 of 12 cases of superficial spreading melanoma. These results suggest that nestin is an important marker of HMB-45-negative melanoma cells in the dermal parts of patients with nodular melanoma.
USDA-ARS?s Scientific Manuscript database
Genetic marker effects and type of inheritance are estimated with poor precision when minor marker allele frequencies are low. A stable composite population (MARC III) was subjected to marker assisted selection for multiple years to equalize specific marker frequencies to 1) estimate effect size an...
USDA-ARS?s Scientific Manuscript database
Genetic marker effects and interactions are estimated with poor precision when minor marker allele frequencies are low. An Angus population was subjected to marker assisted selection for multiple years to increase divergent haplotype and minor marker allele frequencies to 1) estimate effect size an...
Marshall, Tom R; den Boer, Sebastiaan; Cools, Roshan; Jensen, Ole; Fallon, Sean James; Zumer, Johanna M
2018-01-01
Selective attention is reflected neurally in changes in the power of posterior neural oscillations in the alpha (8-12 Hz) and gamma (40-100 Hz) bands. Although a neural mechanism that allows relevant information to be selectively processed has its advantages, it may lead to lucrative or dangerous information going unnoticed. Neural systems are also in place for processing rewarding and punishing information. Here, we examine the interaction between selective attention (left vs. right) and stimulus's learned value associations (neutral, punished, or rewarded) and how they compete for control of posterior neural oscillations. We found that both attention and stimulus-value associations influenced neural oscillations. Whereas selective attention had comparable effects on alpha and gamma oscillations, value associations had dissociable effects on these neural markers of attention. Salient targets (associated with positive and negative outcomes) hijacked changes in alpha power-increasing hemispheric alpha lateralization when salient targets were attended, decreasing it when they were being ignored. In contrast, hemispheric gamma-band lateralization was specifically abolished by negative distractors. Source analysis indicated occipital generators of both attentional and value effects. Thus, posterior cortical oscillations support both the ability to selectively attend while at the same time retaining the ability to remain sensitive to valuable features in the environment. Moreover, the versatility of our attentional system to respond separately to salient from merely positively valued stimuli appears to be carried out by separate neural processes reflected in different frequency bands.
Ghrelin is a prognostic marker and a potential therapeutic target in breast cancer.
Grönberg, Malin; Ahlin, Cecilia; Naeser, Ylva; Janson, Eva Tiensuu; Holmberg, Lars; Fjällskog, Marie-Louise
2017-01-01
Ghrelin and obestatin are gastrointestinal peptides, encoded by the same preproghrelin gene. Both are expressed in breast cancer tissue and ghrelin has been implicated in breast cancer tumorigenesis. Despite recent advances in breast cancer management the need for new prognostic markers and potential therapeutic targets in breast cancer remains high. We studied the prognostic impact of ghrelin and obestatin in women with node negative breast cancer. Within a cohort of women with breast cancer with tumor size ≤ 50 mm, no lymph node metastases and no initiation of adjuvant chemotherapy, 190 women were identified who died from breast cancer and randomly selected 190 women alive at the corresponding time as controls. Tumor tissues were immunostained with antibodies versus the peptides. Ghrelin expression was associated with better breast cancer specific survival in univariate analyses (OR 0.55, 95% CI 0.36-0.84) and in multivariate models, adjusted for endocrine treatment and age (OR 0.57, 95% CI 0.36-0.89). Obestatin expression was non-informative (OR 1.2, 95% CI 0.60-2.46). Ghrelin expression is independent prognostic factor for breast cancer death in node negative patients-halving the risk for dying of breast cancer. Our data implies that ghrelin could be a potential therapeutic target in breast cancer treatment.
Hu, W S; Bowman, E H; Delviks, K A; Pathak, V K
1997-01-01
Homologous recombination and deletions occur during retroviral replication when reverse transcriptase switches templates. While recombination occurs solely by intermolecular template switching (between copackaged RNAs), deletions can occur by an intermolecular or an intramolecular template switch (within the same RNA). To directly compare the rates of intramolecular and intermolecular template switching, two spleen necrosis virus-based vectors were constructed. Each vector contained a 110-bp direct repeat that was previously shown to delete at a high rate. The 110-bp direct repeat was flanked by two different sets of restriction site markers. These vectors were used to form heterozygotic virions containing RNAs of each parental vector, from which recombinant viruses were generated. By analyses of the markers flanking the direct repeats in recombinant and nonrecombinant proviruses, the rates of intramolecular and intermolecular template switching were determined. The results of these analyses indicate that intramolecular template switching is much more efficient than intermolecular template switching and that direct repeat deletions occur primarily through intramolecular template switching events. These studies also indicate that retroviral recombination occurs within a distinct viral subpopulation and exhibits high negative interference, whereby the selection of one recombination event increases the probability that a second recombination event will be observed. PMID:9223494
Novel autoantibody markers for early and seronegative rheumatoid arthritis.
Somers, Klaartje; Geusens, Piet; Elewaut, Dirk; De Keyser, Filip; Rummens, Jean-Luc; Coenen, Marieke; Blom, Marlies; Stinissen, Piet; Somers, Veerle
2011-02-01
Approximately one-third of rheumatoid arthritis (RA) patients are seronegative for the 2 serological RA markers, rheumatoid factor (RF) and antibodies against cyclic citrullinated peptides (ACCP). Moreover, the sensitivities of both markers are lower in the diagnostically important early disease phase. The aim of this study was to identify additional autoantibody markers for early RA and for RF-negative, ACCP-negative (seronegative) RA. We screened an RA synovium cDNA phage display library with autoantibodies in plasma from 10 early (symptoms of maximum 1 year) and 10 seronegative (RF-negative, ACCP-negative) RA patients with validation in 72 additional RA patients and 121 controls (38 healthy controls, 43 patients with other inflammatory rheumatic diseases, 20 osteoarthritis patients and 20 subjects with mechanical joint complaints). Fourteen novel autoantibodies were identified that showed a 54% sensitivity and 90% specificity for RA. For 11 of these autoantibodies, an exclusive presence was demonstrated in RA patients (100% specificity, 37% sensitivity) as compared to controls. All early RA patients were positive for at least one of the identified autoantibodies and antibody-positivity was associated with a shorter disease duration (P = 0.0087). 52% of RA patients who initially tested negative for RF and ACCP, tested positive for at least one of the 14 novel autoantibodies, resulting in a 19% increase in sensitivity compared to current serological testing. Moreover, 5 identified autoantibodies were detected more frequently in seronegative RA patients, indicating that these autoantibodies constitute novel candidate markers for this RA subtype. We demonstrated that the targets of 3 of these 5 autoantibodies had an increased expression in RA synovial tissue compared to control synovial tissue, pointing towards a biological rationale for these auto antibody targets in RA. In conclusion, we identified novel candidate autoantibody markers for RA that can be detected in early and seronegative RA patients indicating the potential added value for RA diagnostics. Copyright © 2010 Elsevier Ltd. All rights reserved.
Niemiec, Joanna A; Adamczyk, Agnieszka; Małecki, Krzysztof; Majchrzyk, Kaja; Ryś, Janusz
2012-12-01
There is still a lack of complete consensus on immunohistochemical surrogate markers for luminal A (LA) and luminal B (LB), HER2, and basal-like subtypes of breast carcinomas and their correlation with cancer cell adhesion and invasion-promoting factors. Therefore, early-stage invasive ductal breast cancer patients (N=209) were recruited to the study and divided into 4 subtypes, on the basis of the expression of the estrogen/progesterone receptor and HER2 (LA: 74.4% of cases; LB: 7.8%; HER2: 5.6%; and triple-negative phenotype: 12.2%). Regardless of the above-mentioned classification, we divided all carcinomas into 2 groups: carcinomas expressing at least 1 basal marker [cytokeratine (CK)5/6, CK5, vimentin, epidermal growth factor receptor, or aberrant CK8/18 expression-membranous or in <10% of cells] versus carcinomas negative for basal markers. Then we studied the relationships between the above subtypes (2 classifications) and (i) the expression of adhesion molecules (Ep-CAM, P-cadherin), (ii) matrix metalloproteinases (MMP)-2, (iii) the proliferation index (MIB-1 LI), and (iv) the microvascular density. We confirmed that triple-negative phenotypes are characterized by basal marker expression, a high tumor grade, and high MIB-1 LI. In this subtype, we found MMP-2 expression in stromal leukocytes less frequently. Both LA carcinomas and carcinomas negative for basal markers were more often negative for epithelial cell adhesion molecule (Ep-CAM) and P-cadherin. Moreover, we noted a higher mean value of microvascular density in CK5/6 and Ep-CAM-immunopositive tumors, carcinomas with aberrant CK8/18 expression, and carcinomas with no or strong expression of MMP-2 in stromal fibroblast-like cells. These results might suggest that mechanisms of stroma remodeling and carcinogenesis (Ep-CAM is the suggested marker of breast progenitors) may differ between breast cancer subtypes.
Criteria for selection and application of molecular markers for clinical studies of osteoarthritis.
Otterness, I G; Swindell, A C
2003-03-01
To develop criteria for the selection and application of molecular markers for the study of osteoarthritis (OA). Statistical criteria for marker selection for OA are developed. After studying more than 20 different molecular markers for monitoring OA, procedures for choosing markers for clinical studies have been developed. For a particular study, the process starts with the markers showing 'face-validity' for monitoring OA. They are next required to successfully distinguish OA patients from controls. This necessitates definition of the distribution of marker values in OA patients and controls. So far, they have been consistently log-normal. The difference (Delta) in marker values between OA and controls defines the opportunity for marker improvement. The between-visit standard deviation (S) in patients puts limits on the detection of marker changes. The two variables can be combined to estimate the practicality of a marker using a modified power analysis. The number of patients (N*) required to observe a 50% improvement with an alpha level of P=0.05 and with 80% certainty is estimated as 50(S/Delta)(2). N*, S and Delta should be used to characterize and compare markers. Marker efficiency can be refined by regressing on secondary variables, such as age, sex, BMI, severity, etc. Finally, the use of two or more markers may be required to improve marker prediction of clinical outcome. Correlated markers can be used to reinforce conclusions by essentially adding replicative data. Independent, complementary markers can be used to develop associations with clinical parameters, and perhaps diagnose and monitor disease status, activities that so far have not been possible with single markers.
Glazko, V I; Zelenaia, L B; Iasinetskaia, N A
1997-01-01
The investigation of genetic interrelation between a number of Artiodactyla and Perissodactyla species with the use of different types of molecular-genetic markers (proteins, RAPD-PCR) were carried out. The marker-specific features of interspecific relations and their similarities on the groups of markers of both types were revealed. The distinctions between interspecies genetic relations and ones estimated from the phylogeny on the determined group of different types of markers were observed. It was supposed that these discrepancies may be related with common selection factors and involving this marker group in selection in some species.
Molecular plant breeding: methodology and achievements.
Varshney, Rajeev K; Hoisington, Dave A; Nayak, Spurthi N; Graner, Andreas
2009-01-01
The progress made in DNA marker technology has been remarkable and exciting in recent years. DNA markers have proved valuable tools in various analyses in plant breeding, for example, early generation selection, enrichment of complex F(1)s, choice of donor parent in backcrossing, recovery of recurrent parent genotype in backcrossing, linkage block analysis and selection. Other main areas of applications of molecular markers in plant breeding include germplasm characterization/fingerprinting, determining seed purity, systematic sampling of germplasm, and phylogenetic analysis. Molecular markers, thus, have proved powerful tools in replacing the bioassays and there are now many examples available to show the efficacy of such markers. We have illustrated some basic concepts and methodology of applying molecular markers for enhancing the selection efficiency in plant breeding. Some successful examples of product developments of molecular breeding have also been presented.
Logistic regression trees for initial selection of interesting loci in case-control studies
Nickolov, Radoslav Z; Milanov, Valentin B
2007-01-01
Modern genetic epidemiology faces the challenge of dealing with hundreds of thousands of genetic markers. The selection of a small initial subset of interesting markers for further investigation can greatly facilitate genetic studies. In this contribution we suggest the use of a logistic regression tree algorithm known as logistic tree with unbiased selection. Using the simulated data provided for Genetic Analysis Workshop 15, we show how this algorithm, with incorporation of multifactor dimensionality reduction method, can reduce an initial large pool of markers to a small set that includes the interesting markers with high probability. PMID:18466557
Selection enhanced estimates of marker effects on means and variances of beef tenderness
USDA-ARS?s Scientific Manuscript database
Genetic marker associations from surveys of industry cattle populations have low frequencies of rare homozygous animals. Selection for calpain (CAPN1) and calpastatin (CAST) genetic markers was replicated in two cattle populations (Angus and MARC III) at the U.S. Meat Animal Research Center. These...
Selective sweep mapping of genes with large phenotypic effects.
Pollinger, John P; Bustamante, Carlos D; Fledel-Alon, Adi; Schmutz, Sheila; Gray, Melissa M; Wayne, Robert K
2005-12-01
Many domestic dog breeds have originated through fixation of discrete mutations by intense artificial selection. As a result of this process, markers in the proximity of genes influencing breed-defining traits will have reduced variation (a selective sweep) and will show divergence in allele frequency. Consequently, low-resolution genomic scans can potentially be used to identify regions containing genes that have a major influence on breed-defining traits. We model the process of breed formation and show that the probability of two or three adjacent marker loci showing a spurious signal of selection within at least one breed (i.e., Type I error or false-positive rate) is low if highly variable and moderately spaced markers are utilized. We also use simulations with selection to demonstrate that even a moderately spaced set of highly polymorphic markers (e.g., one every 0.8 cM) has high power to detect regions targeted by strong artificial selection in dogs. Further, we show that a gene responsible for black coat color in the Large Munsterlander has a 40-Mb region surrounding the gene that is very low in heterozygosity for microsatellite markers. Similarly, we survey 302 microsatellite markers in the Dachshund and find three linked monomorphic microsatellite markers all within a 10-Mb region on chromosome 3. This region contains the FGFR3 gene, which is responsible for achondroplasia in humans, but not in dogs. Consequently, our results suggest that the causative mutation is a gene or regulatory region closely linked to FGFR3.
Algorithms for selecting informative marker panels for population assignment.
Rosenberg, Noah A
2005-11-01
Given a set of potential source populations, genotypes of an individual of unknown origin at a collection of markers can be used to predict the correct source population of the individual. For improved efficiency, informative markers can be chosen from a larger set of markers to maximize the accuracy of this prediction. However, selecting the loci that are individually most informative does not necessarily produce the optimal panel. Here, using genotypes from eight species--carp, cat, chicken, dog, fly, grayling, human, and maize--this univariate accumulation procedure is compared to new multivariate "greedy" and "maximin" algorithms for choosing marker panels. The procedures generally suggest similar panels, although the greedy method often recommends inclusion of loci that are not chosen by the other algorithms. In seven of the eight species, when applied to five or more markers, all methods achieve at least 94% assignment accuracy on simulated individuals, with one species--dog--producing this level of accuracy with only three markers, and the eighth species--human--requiring approximately 13-16 markers. The new algorithms produce substantial improvements over use of randomly selected markers; where differences among the methods are noticeable, the greedy algorithm leads to slightly higher probabilities of correct assignment. Although none of the approaches necessarily chooses the panel with optimal performance, the algorithms all likely select panels with performance near enough to the maximum that they all are suitable for practical use.
Luo, Zhijing; Chen, Mingjiao; Zhao, Xiangxiang; Zhang, Dabing; Qi, Yiping; Yuan, Zheng
2016-01-01
Rapid and accurate genome-wide marker detection is essential to the marker-assisted breeding and functional genomics studies. In this work, we developed an integrated software, AgroMarker Finder (AMF: http://erp.novelbio.com/AMF), for providing graphical user interface (GUI) to facilitate the recently developed restriction-site associated DNA (RAD) sequencing data analysis in rice. By application of AMF, a total of 90,743 high-quality markers (82,878 SNPs and 7,865 InDels) were detected between rice varieties JP69 and Jiaoyuan5A. The density of the identified markers is 0.2 per Kb for SNP markers, and 0.02 per Kb for InDel markers. Sequencing validation revealed that the accuracy of genome-wide marker detection by AMF is 93%. In addition, a validated subset of 82 SNPs and 31 InDels were found to be closely linked to 117 important agronomic trait genes, providing a basis for subsequent marker-assisted selection (MAS) and variety identification. Furthermore, we selected 12 markers from 31 validated InDel markers to identify seed authenticity of variety Jiaoyuanyou69, and we also identified 10 markers closely linked to the fragrant gene BADH2 to minimize linkage drag for Wuxiang075 (BADH2 donor)/Jiachang1 recombinants selection. Therefore, this software provides an efficient approach for marker identification from RAD-seq data, and it would be a valuable tool for plant MAS and variety protection. PMID:26799713
Fan, Wei; Zong, Jie; Luo, Zhijing; Chen, Mingjiao; Zhao, Xiangxiang; Zhang, Dabing; Qi, Yiping; Yuan, Zheng
2016-01-01
Rapid and accurate genome-wide marker detection is essential to the marker-assisted breeding and functional genomics studies. In this work, we developed an integrated software, AgroMarker Finder (AMF: http://erp.novelbio.com/AMF), for providing graphical user interface (GUI) to facilitate the recently developed restriction-site associated DNA (RAD) sequencing data analysis in rice. By application of AMF, a total of 90,743 high-quality markers (82,878 SNPs and 7,865 InDels) were detected between rice varieties JP69 and Jiaoyuan5A. The density of the identified markers is 0.2 per Kb for SNP markers, and 0.02 per Kb for InDel markers. Sequencing validation revealed that the accuracy of genome-wide marker detection by AMF is 93%. In addition, a validated subset of 82 SNPs and 31 InDels were found to be closely linked to 117 important agronomic trait genes, providing a basis for subsequent marker-assisted selection (MAS) and variety identification. Furthermore, we selected 12 markers from 31 validated InDel markers to identify seed authenticity of variety Jiaoyuanyou69, and we also identified 10 markers closely linked to the fragrant gene BADH2 to minimize linkage drag for Wuxiang075 (BADH2 donor)/Jiachang1 recombinants selection. Therefore, this software provides an efficient approach for marker identification from RAD-seq data, and it would be a valuable tool for plant MAS and variety protection.
Brøndum, R F; Su, G; Janss, L; Sahana, G; Guldbrandtsen, B; Boichard, D; Lund, M S
2015-06-01
This study investigated the effect on the reliability of genomic prediction when a small number of significant variants from single marker analysis based on whole genome sequence data were added to the regular 54k single nucleotide polymorphism (SNP) array data. The extra markers were selected with the aim of augmenting the custom low-density Illumina BovineLD SNP chip (San Diego, CA) used in the Nordic countries. The single-marker analysis was done breed-wise on all 16 index traits included in the breeding goals for Nordic Holstein, Danish Jersey, and Nordic Red cattle plus the total merit index itself. Depending on the trait's economic weight, 15, 10, or 5 quantitative trait loci (QTL) were selected per trait per breed and 3 to 5 markers were selected to tag each QTL. After removing duplicate markers (same marker selected for more than one trait or breed) and filtering for high pairwise linkage disequilibrium and assaying performance on the array, a total of 1,623 QTL markers were selected for inclusion on the custom chip. Genomic prediction analyses were performed for Nordic and French Holstein and Nordic Red animals using either a genomic BLUP or a Bayesian variable selection model. When using the genomic BLUP model including the QTL markers in the analysis, reliability was increased by up to 4 percentage points for production traits in Nordic Holstein animals, up to 3 percentage points for Nordic Reds, and up to 5 percentage points for French Holstein. Smaller gains of up to 1 percentage point was observed for mastitis, but only a 0.5 percentage point increase was seen for fertility. When using a Bayesian model accuracies were generally higher with only 54k data compared with the genomic BLUP approach, but increases in reliability were relatively smaller when QTL markers were included. Results from this study indicate that the reliability of genomic prediction can be increased by including markers significant in genome-wide association studies on whole genome sequence data alongside the 54k SNP set. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Imaging markers for Alzheimer disease
Bocchetta, Martina; Chételat, Gael; Rabinovici, Gil D.; de Leon, Mony J.; Kaye, Jeffrey; Reiman, Eric M.; Scheltens, Philip; Barkhof, Frederik; Black, Sandra E.; Brooks, David J.; Carrillo, Maria C.; Fox, Nick C.; Herholz, Karl; Nordberg, Agneta; Jack, Clifford R.; Jagust, William J.; Johnson, Keith A.; Rowe, Christopher C.; Sperling, Reisa A.; Thies, William; Wahlund, Lars-Olof; Weiner, Michael W.; Pasqualetti, Patrizio; DeCarli, Charles
2013-01-01
Revised diagnostic criteria for Alzheimer disease (AD) acknowledge a key role of imaging biomarkers for early diagnosis. Diagnostic accuracy depends on which marker (i.e., amyloid imaging, 18F-fluorodeoxyglucose [FDG]-PET, SPECT, MRI) as well as how it is measured (“metric”: visual, manual, semiautomated, or automated segmentation/computation). We evaluated diagnostic accuracy of marker vs metric in separating AD from healthy and prognostic accuracy to predict progression in mild cognitive impairment. The outcome measure was positive (negative) likelihood ratio, LR+ (LR−), defined as the ratio between the probability of positive (negative) test outcome in patients and the probability of positive (negative) test outcome in healthy controls. Diagnostic LR+ of markers was between 4.4 and 9.4 and LR− between 0.25 and 0.08, whereas prognostic LR+ and LR− were between 1.7 and 7.5, and 0.50 and 0.11, respectively. Within metrics, LRs varied up to 100-fold: LR+ from approximately 1 to 100; LR− from approximately 1.00 to 0.01. Markers accounted for 11% and 18% of diagnostic and prognostic variance of LR+ and 16% and 24% of LR−. Across all markers, metrics accounted for an equal or larger amount of variance than markers: 13% and 62% of diagnostic and prognostic variance of LR+, and 29% and 18% of LR−. Within markers, the largest proportion of diagnostic LR+ and LR− variability was within 18F-FDG-PET and MRI metrics, respectively. Diagnostic and prognostic accuracy of imaging AD biomarkers is at least as dependent on how the biomarker is measured as on the biomarker itself. Standard operating procedures are key to biomarker use in the clinical routine and drug trials. PMID:23897875
Singh, Neeta; Malik, Ekta; Banerjee, Ayan; Chosdol, Kunzang; Sreenivas, V; Mittal, Suneeta
2013-08-01
To measure the levels of early follicular phase Anti-Mullerian hormone (AMH) in Indian patients of IVF and to evaluate the AMH as a predictive marker of ovarian response in assisted reproductive technology outcome. Sixty women (age 25-40 years) selected for in vitro fertilization treatment were included in this study. Analysis of day-2 serum samples was done for the AMH, FSH, Inhibin B, and LH by ELISA kit methods. USG was done for the antral follicle count (AFC) and oocytes' retrieval. Hormone parameters were compared and correlated with the oocytes' retrieval count and the AFC. The discriminant analysis was done to compare relevance of different parameters for predicting ovarian response. The Anti-Mullerian hormone showed a significant correlation with the oocytes' retrieval after ovulation induction for IVF (r = 0.648, p < 0.0001) and no correlation was seen with serum FSH, LH, and Inhibin. Serum AMH levels show 80 % sensitivity and 80 % specificity in predicting poor ovarian response. There is a significant correlation between day-2 serum AMH levels and the oocytes' retrieval count in women undergoing ovulation induction for IVF, and the AMH is a good marker as the negative predictive values for the success of ART. There is no correlation found between other hormonal ovarian reserve markers and the oocytes' retrieval count.
Radojewski, Mateusz; Podgórski, Tomasz; Pospieszna, Barbara; Kryściak, Jakub; Śliwicka, Ewa; Karolkiewicz, Joanna
2018-06-01
The aim of the study was to evaluate the impact of the competitive phase on physiological and metabolic indices and selected markers of skeletal muscle damage in male volleyball players. The study group consisted of 24 young male volleyball players. During the study, participants underwent two series of measurements, before and after the competitive phase of the annual training cycle. In both study terms, players performed an incremental treadmill running test to determine their ventilatory threshold and maximal oxygen uptake. Venous and capillary blood samples were taken for biochemical analysis. There was no significant difference in the physical fitness level, values of biochemical variables and the level of antioxidant status in the surveyed athletes between the two study terms. Significant changes within skeletal muscle damage markers were observed between the beginning and the end of the competitive period: an increase in the concentration of cellular DNA damage products (8-hydroxy-2'-deoxyguanosine; p < 0.0001) and a decrease in muscle activity of creatine kinase (p<0.05). In spite of the increment in cell damage markers, the unaffected level of physiological and biochemical markers may indicate that the experienced cell destruction did not negatively affect the level of physical fitness. When designing the annual training plan, coaches and athletes need to take into consideration that temporary physiological states - oxidative stress and inflammation - may be required to attain training adaptation.
Student, Vladimir; Vidlar, Ales; Bouchal, Jan; Vrbkova, Jana; Kolar, Zdenek; Kral, Milan; Kosina, Pavel; Vostalova, Jitka
2016-12-01
Recently, we described an inverse association between cranberry supplementation and serum prostate specific antigen (PSA) in patients with negative biopsy for prostate cancer (PCa) and chronic nonbacterial prostatitis. This double blind placebo controlled study evaluates the effects of cranberry consumption on PSA values and other markers in men with PCa before radical prostatectomy. Prior to surgery, 64 patients with prostate cancer were randomized to a cranberry or placebo group. The cranberry group (n=32) received a mean 30 days of 1500 mg cranberry fruit powder. The control group (n=32) took a similar amount of placebo. Selected blood/urine markers as well as free and total phenolics in urine were measured at baseline and on the day of surgery in both groups. Prostate tissue markers were evaluated after surgery. The serum PSA significantly decreased by 22.5% in the cranberry arm (n=31, P<0.05). A trend to down-regulation of urinary beta-microseminoprotein (MSMB) and serum gamma-glutamyltranspeptidase, as well as upregulation of IGF-1 was found after cranberry supplementation. There were no changes in prostate tissue markers or, composition and concentration of phenolics in urine. Daily consumption of a powdered cranberry fruit lowered serum PSA in patients with prostate cancer. The whole fruit contains constituents that may regulate the expression of androgen-responsive genes.
Charles W. Stuber: Maize geneticist and pioneer of marker-assisted selection
USDA-ARS?s Scientific Manuscript database
Charles W. Stuber is considered a pioneer of quantitative genetic mapping and marker-assisted selection in maize. The achievements of his four decade career in research include the development of genetic marker systems used in maize and adapted in many other crops, the first methods and studies to i...
DNA fingerprinting sets for four southern pines
Craig Echt; Sedley Josserand
2018-01-01
DNA markers can provide valuable genetic information for forest tree research, breeding, conservation, and restoration programs. When properly evaluated, selected sets of DNA markers can be used to efficiently get information about genetic diversity in regions, forests, or stands, or in seed lots and orchards. Selected markers also can be used to determine parentage or...
Selection for avian immune response: a commercial breeding company challenge.
Fulton, J E
2004-04-01
Selection for immune function in the commercial breeding environment is a challenging proposition for commercial breeding companies. Immune response is only one of many traits that are under intensive selection, thus selection pressure needs to be carefully balanced across multiple traits. The selection environment (single bird cages, biosecure facilities, controlled environment) is a very different environment than the commercial production facilities (multiple bird cages, potential disease exposure, variable environment) in which birds are to produce. The testing of individual birds is difficult, time consuming, and expensive. It is essential that the results of any tests be relevant to actual disease or environmental challenge in the commercial environment. The use of genetic markers as indicators of immune function is being explored by breeding companies. Use of genetic markers would eliminate many of the limitations in enhancing immune function currently encountered by commercial breeding companies. Information on genetic markers would allow selection to proceed without subjecting breeding stock to disease conditions and could be done before production traits are measured. These markers could be candidate genes with known interaction or involvement with disease pathology or DNA markers that are closely linked to genetic regions that influence the immune response. The current major limitation to this approach is the paucity of mapped chicken immune response genes and the limited number of DNA markers mapped on the chicken genome. These limitations should be eliminated once the chicken genome is sequenced.
Bhatt, Mukesh; Mohapatra, Jajati K; Pandey, Laxmi K; Mohanty, Nihar N; Das, Biswajit; Prusty, Bikash R; Pattnaik, Bramhadev
2018-01-02
Inactivated purified whole virus vaccines are used for control of foot and mouth disease (FMD). ELISAs detecting antibodies to the nonstructural proteins (NSP), a marker of infection, are primarily used to differentiate FMD virus (FMDV) infected from vaccinated animals (DIVA). However, such DIVA assays have a limitation to their specificity since residual NSPs present in the relatively impure vaccines are suspected to induce an NSP-antibody response in the repeatedly vaccinated animals. Epitope-deleted negative marker vaccine strategy seems to have an advantage over the conventional vaccines in identifying the infected animals with accuracy. NSP 3AB contains an abundance of immunodominant B-cell epitopes of diagnostic importance. This study addresses the feasibility of producing 3AB-truncated FMDV mutant as a potential negative marker vaccine candidate. An infectious cDNA clone of FMDV serotype Asia 1 strain was used to engineer an array of deletion mutations in the established antigenic domain of 3AB. The maximum length of deletion tolerated by the virus was found to be restricted to amino acid residues 87-144 in the C-terminal half of 3A protein along with deletion of the first two copies of 3B peptide. The 3AB-truncated marker virus (Asia 1 IND 491/1997Δ3A 87-144 3B 1,2 +FLAG) demonstrated infectivity titres comparable to that of the parental virus in BHK-21 (log 10 7.42 TCID 50 /ml) and LFBK-α V β 6 (log 10 8.30 TCID 50 /ml) cell monolayer culture. The protein fragment corresponding to the viable deletion in the 3AB region was expressed in a prokaryotic system to standardize a companion assay (3A 87-153 3B 1,2 I-ELISA) for the negative marker virus which showed reasonably high diagnostic sensitivity (96.9%) and specificity (100% for naïve and 97.1% for uninfected vaccinated samples). The marker virus and its companion ELISA designed in this study provide a basis to devise a marker vaccine strategy for FMD control. Copyright © 2017 Elsevier B.V. All rights reserved.
O Specht, Ina; Spanò, Marcello; S Hougaard, Karin; C Manicardi, Gian; Bizzaro, Davide; Toft, Gunnar; Giwercman, Aleksander; E Bonde, Jens-Peter
2012-01-01
Apoptosis in the testis has two putative roles during normal spermatogenesis; limitation of the germ cell population to numbers that can be supported by the Sertoli cells, and, possibly, selective depletion of meiotic and postmeiotic abnormal germ cells. We investigated the demographic and biological correlates of the pro-apoptotic marker Fas and the anti-apoptotic marker Bcl-xL in sperm cells of fertile men. Six hundred and four men from Greenland, Poland and Ukraine were consecutively enrolled during their pregnant wife's antenatal visits. Semen analysis was performed as recommended by the World Health Organization. Immunofluorescence coupled to flow cytometry was utilized for detection of apoptotic markers in the sperm cell. DNA damage was assessed by flow cytometry using both the sperm chromatin structure assay (SCSA) and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay. The percentage of Fas-positive sperm cells was higher in men with high total sperm count (P<0.01), more motile sperms (P=0.04) and fewer sperm head defects (P=0.05). These associations were consistent within and across study regions. Furthermore, testosterone, follicle-stimulating hormone (FSH) and sexual hormone-binding globulin (SHBG) were significantly negatively correlated with Fas within and across regions as well. The data indicated no association between the anti-apoptotic Bcl-xL marker and semen or personal characteristics. The finding of Fas-positive sperm cells associated with better semen quality in a cohort of spouses of pregnant women seems different from previous data obtained in infertile men and warrants further investigation to clarify the biological significance of sperm apoptotic markers. PMID:23064689
Tabatabaei, Iman; Ruf, Stephanie; Bock, Ralph
2017-02-01
A new selectable marker gene for stable transformation of the plastid genome was developed that is similarly efficient as the aadA, and produces no background of spontaneous resistance mutants. More than 25 years after its development for Chlamydomonas and tobacco, the transformation of the chloroplast genome still represents a challenging technology that is available only in a handful of species. The vast majority of chloroplast transformation experiments conducted thus far have relied on a single selectable marker gene, the spectinomycin resistance gene aadA. Although a few alternative markers have been reported, the aadA has remained unrivalled in efficiency and is, therefore, nearly exclusively used. The development of new marker genes for plastid transformation is of crucial importance to all efforts towards extending the species range of the technology as well as to those applications in basic research, biotechnology and synthetic biology that involve the multistep engineering of plastid genomes. Here, we have tested a bifunctional resistance gene for its suitability as a selectable marker for chloroplast transformation. The bacterial enzyme aminoglycoside acetyltransferase(6')-Ie/aminoglycoside phosphotransferase(2″)-Ia possesses an N-terminal acetyltransferase domain and a C-terminal phosphotransferase domain that can act synergistically and detoxify aminoglycoside antibiotics highly efficiently. We report that, in combination with selection for resistance to the aminoglycoside tobramycin, the aac(6')-Ie/aph(2″)-Ia gene represents an efficient marker for plastid transformation in that it produces similar numbers of transplastomic lines as the spectinomycin resistance gene aadA. Importantly, no spontaneous antibiotic resistance mutants appear under tobramycin selection.
Update on Aire and thymic negative selection.
Passos, Geraldo A; Speck-Hernandez, Cesar A; Assis, Amanda F; Mendes-da-Cruz, Daniella A
2018-01-01
Twenty years ago, the autoimmune regulator (Aire) gene was associated with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, and was cloned and sequenced. Its importance goes beyond its abstract link with human autoimmune disease. Aire identification opened new perspectives to better understand the molecular basis of central tolerance and self-non-self distinction, the main properties of the immune system. Since 1997, a growing number of immunologists and molecular geneticists have made important discoveries about the function of Aire, which is essentially a pleiotropic gene. Aire is one of the functional markers in medullary thymic epithelial cells (mTECs), controlling their differentiation and expression of peripheral tissue antigens (PTAs), mTEC-thymocyte adhesion and the expression of microRNAs, among other functions. With Aire, the immunological tolerance became even more apparent from the molecular genetics point of view. Currently, mTECs represent the most unusual cells because they express almost the entire functional genome but still maintain their identity. Due to the enormous diversity of PTAs, this uncommon gene expression pattern was termed promiscuous gene expression, the interpretation of which is essentially immunological - i.e. it is related to self-representation in the thymus. Therefore, this knowledge is strongly linked to the negative selection of autoreactive thymocytes. In this update, we focus on the most relevant results of Aire as a transcriptional and post-transcriptional controller of PTAs in mTECs, its mechanism of action, and its influence on the negative selection of autoreactive thymocytes as the bases of the induction of central tolerance and prevention of autoimmune diseases. © 2017 John Wiley & Sons Ltd.
Genome-enabled prediction models for yield related traits in chickpea
USDA-ARS?s Scientific Manuscript database
Genomic selection (GS) unlike marker-assisted backcrossing (MABC) predicts breeding values of lines using genome-wide marker profiling and allows selection of lines prior to field-phenotyping, thereby shortening the breeding cycle. A collection of 320 elite breeding lines was selected and phenotyped...
Sahnoun, Sana; Sellami, Afifa; Chakroun, Nozha; Mseddi, Malek; Attia, Hammadi; Rebai, Tarek; Lassoued, Saloua
2017-08-01
To study the role of Toll-like receptor 4 (TLR4) in human spermatozoa and to assess sperm parameters, oxidative stress markers, and acrosome reaction in response to the stimulation of TLR4 by its ligand, the lipopolysaccharide (LPS), as a major endotoxin of Gram-negative bacteria. Our study was carried out in 73 sperm samples from patients undergoing semen analysis for couple infertility investigations. The studied patients were divided into three groups: normozoospermic fertile patients (n = 13), patients with abnormal and leukospermic semen (n = 13), and patients with abnormal and non-leukospermic semen (n = 47). TLR4 expression in human spermatozoa was initially analyzed by western blot. Sperm samples were incubated in the presence of LPS (200 ng/ml) for 18 h. Then, sperm motility and vitality were evaluated by microscopic observation and oxidative stress markers as malondialdehyde (MDA) and carbonyl groups (CG) were spectrophotometrically assessed in neat and selected sperm. A triple-stain technique was also performed to evaluate acrosome reaction in 15 sperm samples from infertile patients. TLR4 expression was confirmed in human spermatozoa with a molecular weight of 69 kDa. In the normozoospermic group, no significant differences in sperm parameters and oxidative stress markers were shown after incubation with LPS in neat and selected sperms. Regarding samples from the non-leukospermic group, LPS reduced spermatozoa motility and vitality rates in selected sperm (P = 0.003; P = 0.004, respectively). A significant increase of MDA and CG levels was also detected (P = 0.01; P = 0.02, respectively). However, only the MDA levels were significantly increased (P = 0.01) in neat LPS-stimulated sperm. The same results were shown within the leukospermic group. The comparison between the two groups, leukospermic and non-leukospermic, in selected sperms showed a more important LPS effect in the leukospermic group significantly on motility and MDA rates (P = 0.006; P = 0.009, respectively). Furthermore, a significant decrease in reacted spermatozoa rate was detected in response to LPS in selected sperm samples from infertile men (P = 0.03). These findings indicate that human spermatozoa express TLR4 and respond to LPS stimulation with alterations in viability, motility, and the acrosome reaction implicating reactive oxygen species (ROS) production in sperm samples from infertile patients.
Maalouf, Fadi T; Clark, Luke; Tavitian, Lucy; Sahakian, Barbara J; Brent, David; Phillips, Mary L
2012-06-30
The aim of the current research was to examine for the first time the extent to which bias to negative emotions in an inhibitory control paradigm is a state or trait marker in major depressive disorder (MDD) in adolescents. We administered the affective go/no go task which measures the ability to switch attention to or away from positive or negative emotional stimuli to 40 adolescents with MDD (20 in acute episode (MDDa) and 20 in remission (MDDr)) and 17 healthy controls (HC). MDDa were significantly faster on the shift to negative target blocks as compared to shift to positive target blocks while HC and MDDr displayed the opposite pattern as measured by an "emotional bias index" (EBI=latency (shift to negative targets)-latency (shift to positive targets)). There was also a trend for an effect of group on commission errors, suggesting more impulsive responding by MDDa than both MDDr and HC independently of stimulus valence throughout the task. Negative bias was not associated with depression severity or medication status. In conclusion, bias to negative emotional stimuli appears to be present in the acute stage of MDD and absent in remission suggesting that it is a depression state-specific marker of MDD in adolescents. Latency emerges as a better proxy of negative bias than commission errors and accuracy on this inhibitory control task in adolescents with MDD. Copyright © 2012 Elsevier Ltd. All rights reserved.
EMT and EGFR in CTCs cytokeratin negative non-metastatic breast cancer
Alvarez-Cubero, Maria J.; Nadal, Rosa; Sanchez-Rovira, Pedro; Salido, Marta; Rodríguez, María; García-Puche, Jose L.; Delgado-Rodriguez, Miguel; Solé, Francisco; García, Maria A.; Perán, Macarena; Rosell, Rafael; Marchal, Juan A.; Lorente, Jose A.
2014-01-01
Circulating tumor cells (CTCs) are frequently associated with epithelialmesenchymal transition (EMT). The objective of this study was to detect EMT phenotype through Vimentin (VIM) and Slug expression in cytokeratin (CK)-negative CTCs in non-metastatic breast cancer patients and to determine the importance of EGFR in the EMT phenomenon. In CK-negative CTCs samples, both VIM and Slug markers were co-expressed in the most of patients. Among patients EGFR+, half of them were positive for these EMT markers. Furthermore, after a systemic treatment 68% of patients switched from CK- to CK+ CTCs. In our experimental model we found that activation of EGFR signaling by its ligand on MCF-7 cells is sufficient to increase EMT phenotypes, to inhibit apoptotic events and to induce the loss of CK expression. The simultaneous detection of both EGFR and EMT markers in CTCs may improve prognostic or predictive information in patients with operable breast cancer. PMID:25277187
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Shiyu; Kaeppler, Shawn M.; Vogel, Kenneth P.
Switchgrass is undergoing development as a dedicated cellulosic bioenergy crop. Fermentation of lignocellulosic biomass to ethanol in a bioenergy system or to volatile fatty acids in a livestock production system is strongly and negatively influenced by lignification of cell walls. This study detects specific loci that exhibit selection signatures across switchgrass breeding populations that differ in in vitro dry matter digestibility (IVDMD), ethanol yield, and lignin concentration. Allele frequency changes in candidate genes were used to detect loci under selection. Out of the 183 polymorphisms identified in the four candidate genes, twenty-five loci in the intron regions and four locimore » in coding regions were found to display a selection signature. All loci in the coding regions are synonymous substitutions. Selection in both directions were observed on polymorphisms that appeared to be under selection. Genetic diversity and linkage disequilibrium within the candidate genes were low. The recurrent divergent selection caused excessive moderate allele frequencies in the cycle 3 reduced lignin population as compared to the base population. As a result, this study provides valuable insight on genetic changes occurring in short-term selection in the polyploid populations, and discovered potential markers for breeding switchgrass with improved biomass quality.« less
Chen, Shiyu; Kaeppler, Shawn M.; Vogel, Kenneth P.; ...
2016-11-28
Switchgrass is undergoing development as a dedicated cellulosic bioenergy crop. Fermentation of lignocellulosic biomass to ethanol in a bioenergy system or to volatile fatty acids in a livestock production system is strongly and negatively influenced by lignification of cell walls. This study detects specific loci that exhibit selection signatures across switchgrass breeding populations that differ in in vitro dry matter digestibility (IVDMD), ethanol yield, and lignin concentration. Allele frequency changes in candidate genes were used to detect loci under selection. Out of the 183 polymorphisms identified in the four candidate genes, twenty-five loci in the intron regions and four locimore » in coding regions were found to display a selection signature. All loci in the coding regions are synonymous substitutions. Selection in both directions were observed on polymorphisms that appeared to be under selection. Genetic diversity and linkage disequilibrium within the candidate genes were low. The recurrent divergent selection caused excessive moderate allele frequencies in the cycle 3 reduced lignin population as compared to the base population. As a result, this study provides valuable insight on genetic changes occurring in short-term selection in the polyploid populations, and discovered potential markers for breeding switchgrass with improved biomass quality.« less
Boboila, Shuobo; Lopez, Gonzalo; Yu, Jiyang; Banerjee, Debarshi; Kadenhe-Chiweshe, Angela; Connolly, Eileen P; Kandel, Jessica J; Rajbhandari, Presha; Silva, Jose M; Califano, Andrea; Yamashiro, Darrell J
2018-06-07
Despite the identification of MYCN amplification as an adverse prognostic marker in neuroblastoma, MYCN inhibitors have yet to be developed. Here, by integrating evidence from a whole-genome shRNA library screen and the computational inference of master regulator proteins, we identify transcription factor activating protein 4 (TFAP4) as a critical effector of MYCN amplification in neuroblastoma, providing a novel synthetic lethal target. We demonstrate that TFAP4 is a direct target of MYCN in neuroblastoma cells, and that its expression and activity strongly negatively correlate with neuroblastoma patient survival. Silencing TFAP4 selectively inhibits MYCN-amplified neuroblastoma cell growth both in vitro and in vivo, in xenograft mouse models. Mechanistically, silencing TFAP4 induces neuroblastoma differentiation, as evidenced by increased neurite outgrowth and upregulation of neuronal markers. Taken together, our results demonstrate that TFAP4 is a key regulator of MYCN-amplified neuroblastoma and may represent a valuable novel therapeutic target.
Applying a new mammographic imaging marker to predict breast cancer risk
NASA Astrophysics Data System (ADS)
Aghaei, Faranak; Danala, Gopichandh; Hollingsworth, Alan B.; Stoug, Rebecca G.; Pearce, Melanie; Liu, Hong; Zheng, Bin
2018-02-01
Identifying and developing new mammographic imaging markers to assist prediction of breast cancer risk has been attracting extensive research interest recently. Although mammographic density is considered an important breast cancer risk, its discriminatory power is lower for predicting short-term breast cancer risk, which is a prerequisite to establish a more effective personalized breast cancer screening paradigm. In this study, we presented a new interactive computer-aided detection (CAD) scheme to generate a new quantitative mammographic imaging marker based on the bilateral mammographic tissue density asymmetry to predict risk of cancer detection in the next subsequent mammography screening. An image database involving 1,397 women was retrospectively assembled and tested. Each woman had two digital mammography screenings namely, the "current" and "prior" screenings with a time interval from 365 to 600 days. All "prior" images were originally interpreted negative. In "current" screenings, these cases were divided into 3 groups, which include 402 positive, 643 negative, and 352 biopsy-proved benign cases, respectively. There is no significant difference of BIRADS based mammographic density ratings between 3 case groups (p < 0.6). When applying the CAD-generated imaging marker or risk model to classify between 402 positive and 643 negative cases using "prior" negative mammograms, the area under a ROC curve is 0.70+/-0.02 and the adjusted odds ratios show an increasing trend from 1.0 to 8.13 to predict the risk of cancer detection in the "current" screening. Study demonstrated that this new imaging marker had potential to yield significantly higher discriminatory power to predict short-term breast cancer risk.
NASA Technical Reports Server (NTRS)
Tarabalka, Y.; Tilton, J. C.; Benediktsson, J. A.; Chanussot, J.
2012-01-01
The Hierarchical SEGmentation (HSEG) algorithm, which combines region object finding with region object clustering, has given good performances for multi- and hyperspectral image analysis. This technique produces at its output a hierarchical set of image segmentations. The automated selection of a single segmentation level is often necessary. We propose and investigate the use of automatically selected markers for this purpose. In this paper, a novel Marker-based HSEG (M-HSEG) method for spectral-spatial classification of hyperspectral images is proposed. Two classification-based approaches for automatic marker selection are adapted and compared for this purpose. Then, a novel constrained marker-based HSEG algorithm is applied, resulting in a spectral-spatial classification map. Three different implementations of the M-HSEG method are proposed and their performances in terms of classification accuracies are compared. The experimental results, presented for three hyperspectral airborne images, demonstrate that the proposed approach yields accurate segmentation and classification maps, and thus is attractive for remote sensing image analysis.
Espindola, S M C G; Hamawaki, O T; Oliveira, A P; Hamawaki, C D L; Hamawaki, R L; Takahashi, L M
2016-03-11
The soybean cyst nematode (SCN) is a major cause of soybean yield reduction. The objective of this study was to evaluate the efficiency of marker-assisted selection to identify genotypes resistant to SCN race 3 infection, using Sat_168 and Sat-141 resistance quantitative trait loci. The experiment was carried out under greenhouse conditions, using soybean populations originated from crosses between susceptible and resistant parent stock: CD-201 (susceptible) and Foster IAC (resistant), Conquista (susceptible) and S83-30 (resistant), La-Suprema (susceptible) and S57-11 (resistant), and Parecis (susceptible) and S65-50 (resistant). Plants were inoculated with SCN and evaluated according to the female index (FI), those with FI < 10% were classified as resistant to nematode infection. Plants were genotyped for SCN resistance using microsatellite markers Sat-141 and Sat_168. Marker selection efficiency was analyzed by a contingency table, taking into account genotypic versus phenotypic evaluations for each line. These markers were shown to be useful tool for selection of SCN race 3.
Gruber, Steffen; Schwab, Helmut; Koefinger, Petra
2015-12-25
The Gram-negative bacterium Escherichia coli is currently the most efficient and widely used prokaryotic host for recombinant protein and metabolite production. However, due to some limitations and to various interesting features of other Gram-negative bacteria efficient vector systems applicable to a broad range are desired. Basic building blocks for plasmid-based vectors include besides the need for a suitable selection marker in the first line a proper replication and maintenance system. In addition to these basic requirements, further elements are needed for Gram-negative bacteria beyond E. coli, such as Pseudomonas pudita, Ralstonia eutropha, Burkholderia glumae or Acinetobacter sp.. Established building blocks have to be adapted and new building blocks providing the desired functions need to be identified and exploited. This minireview addresses so far described and used genetic elements for broad host range replication, efficient plasmid maintenance, and conjugative plasmid transfer as well as expression elements and protein secretion signals. The industrially important bacterium R. eutropha H16 was chosen as a model organism to provide specific data on the effectivity and utility of building blocks based on such genetic elements. Copyright © 2015 Elsevier B.V. All rights reserved.
Exclusion of primary congenital glaucoma (PCG) from two candidate regions of chromosomes 1 and 6
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarfarazi, M.; Akarsu, A.N.; Barsoum-Homsy, M.
1994-09-01
PCG is a genetically heterogeneous condition in which a significant proportion of families inherit in an autosomally recessive fashion. Although association of PCG with chromosomal abnormalities has been repeatedly reported in the literature, the chromosomal location of this condition is still unknown. Therefore, this study is designed to identify the chromosomal location of the PCG locus by positional mapping. We have identified 80 PCG families with a total of 261 potential informative meiosis. A group of 19 pedigrees with a minimum of 2 affected children in each pedigree and consanguinity in most of the parental generation were selected as ourmore » initial screening panel. This panel consists of a total of 44 affected and 93 unaffected individuals giving a total of 99 informative meiosis, including 5 phase-known. We used polymerase chain reaction (PCR), denaturing polyacrylamide gels and silver staining to genotype our families. We first screened for markers on 1q21-q31, the reported location for juvenile primary open-angle glaucoma and excluded a region of 30 cM as the likely site for the PCG locus. Association of PCG with both ring chromosome 6 and HLA-B8 has also been reported. Therefore, we genotyped our PCG panel with PCR applicable markers from 6p21. Significant negative lod scores were obtained for D6S105 (Z = -18.70) and D6S306 (Z = -5.99) at {theta}=0.001. HLA class 1 region has also contained one of the tubulin genes (TUBB) which is an obvious candidate for PCG. Study of this gene revealed a significant negative lod score with PCG (Z = -16.74, {theta}=0.001). A multipoint linkage analysis of markers in this and other regions containing the candidate genes will be presented.« less
Godlewska, B R; Browning, M; Norbury, R; Cowen, P J; Harmer, C J
2016-11-22
Antidepressant treatment reduces behavioural and neural markers of negative emotional bias early in treatment and has been proposed as a mechanism of antidepressant drug action. Here, we provide a critical test of this hypothesis by assessing whether neural markers of early emotional processing changes predict later clinical response in depression. Thirty-five unmedicated patients with major depression took the selective serotonin re-uptake inhibitor (SSRI), escitalopram (10 mg), over 6 weeks, and were classified as responders (22 patients) versus non-responders (13 patients), based on at least a 50% reduction in symptoms by the end of treatment. The neural response to fearful and happy emotional facial expressions was assessed before and after 7 days of treatment using functional magnetic resonance imaging. Changes in the neural response to these facial cues after 7 days of escitalopram were compared in patients as a function of later clinical response. A sample of healthy controls was also assessed. At baseline, depressed patients showed greater activation to fear versus happy faces than controls in the insula and dorsal anterior cingulate. Depressed patients who went on to respond to the SSRI had a greater reduction in neural activity to fearful versus happy facial expressions after just 7 days of escitalopram across a network of regions including the anterior cingulate, insula, amygdala and thalamus. Mediation analysis confirmed that the direct effect of neural change on symptom response was not mediated by initial changes in depressive symptoms. These results support the hypothesis that early changes in emotional processing with antidepressant treatment are the basis of later clinical improvement. As such, early correction of negative bias may be a key mechanism of antidepressant drug action and a potentially useful predictor of therapeutic response.
Genetic diversity and trait genomic prediction in a pea diversity panel.
Burstin, Judith; Salloignon, Pauline; Chabert-Martinello, Marianne; Magnin-Robert, Jean-Bernard; Siol, Mathieu; Jacquin, Françoise; Chauveau, Aurélie; Pont, Caroline; Aubert, Grégoire; Delaitre, Catherine; Truntzer, Caroline; Duc, Gérard
2015-02-21
Pea (Pisum sativum L.), a major pulse crop grown for its protein-rich seeds, is an important component of agroecological cropping systems in diverse regions of the world. New breeding challenges imposed by global climate change and new regulations urge pea breeders to undertake more efficient methods of selection and better take advantage of the large genetic diversity present in the Pisum sativum genepool. Diversity studies conducted so far in pea used Simple Sequence Repeat (SSR) and Retrotransposon Based Insertion Polymorphism (RBIP) markers. Recently, SNP marker panels have been developed that will be useful for genetic diversity assessment and marker-assisted selection. A collection of diverse pea accessions, including landraces and cultivars of garden, field or fodder peas as well as wild peas was characterised at the molecular level using newly developed SNP markers, as well as SSR markers and RBIP markers. The three types of markers were used to describe the structure of the collection and revealed different pictures of the genetic diversity among the collection. SSR showed the fastest rate of evolution and RBIP the slowest rate of evolution, pointing to their contrasted mode of evolution. SNP markers were then used to predict phenotypes -the date of flowering (BegFlo), the number of seeds per plant (Nseed) and thousand seed weight (TSW)- that were recorded for the collection. Different statistical methods were tested including the LASSO (Least Absolute Shrinkage ans Selection Operator), PLS (Partial Least Squares), SPLS (Sparse Partial Least Squares), Bayes A, Bayes B and GBLUP (Genomic Best Linear Unbiased Prediction) methods and the structure of the collection was taken into account in the prediction. Despite a limited number of 331 markers used for prediction, TSW was reliably predicted. The development of marker assisted selection has not reached its full potential in pea until now. This paper shows that the high-throughput SNP arrays that are being developed will most probably allow for a more efficient selection in this species.
Energy and Nutrient Intake Monitoring
NASA Technical Reports Server (NTRS)
Luckey, T. D.; Venugopal, B.; Hutcheson, D. P.
1975-01-01
A passive system to determine the in-flight intake of nutrients is developed. Nonabsorbed markers placed in all foods in proportion to the nutrients selected for study are analyzed by neutron activation analysis. Fecal analysis for each market indicates how much of the nutrients were eaten and apparent digestibility. Results of feasibility tests in rats, mice, and monkeys indicate the diurnal variation of several markers, the transit time for markers in the alimentary tract, the recovery of several markers, and satisfactory use of selected markers to provide indirect measurement of apparent digestibility. Recommendations are provided for human feasibility studies.
Development of marker-free transgenic lettuce resistant to Mirafiori lettuce big-vein virus.
Kawazu, Yoichi; Fujiyama, Ryoi; Imanishi, Shunsuke; Fukuoka, Hiroyuki; Yamaguchi, Hirotaka; Matsumoto, Satoru
2016-10-01
Lettuce big-vein disease caused by Mirafiori lettuce big-vein virus (MLBVV) is found in major lettuce production areas worldwide, but highly resistant cultivars have not yet been developed. To produce MLBVV-resistant marker-free transgenic lettuce that would have a transgene with a promoter and terminator of lettuce origin, we constructed a two T-DNA binary vector, in which the first T-DNA contained the selectable marker gene neomycin phosphotransferase II, and the second T-DNA contained the lettuce ubiquitin gene promoter and terminator and inverted repeats of the coat protein (CP) gene of MLBVV. This vector was introduced into lettuce cultivars 'Watson' and 'Fuyuhikari' by Agrobacterium tumefaciens-mediated transformation. Regenerated plants (T0 generation) that were CP gene-positive by PCR analysis were self-pollinated, and 312 T1 lines were analyzed for resistance to MLBVV. Virus-negative plants were checked for the CP gene and the marker gene, and nine lines were obtained which were marker-free and resistant to MLBVV. Southern blot analysis showed that three of the nine lines had two copies of the CP gene, whereas six lines had a single copy and were used for further analysis. Small interfering RNAs, which are indicative of RNA silencing, were detected in all six lines. MLBVV infection was inhibited in all six lines in resistance tests performed in a growth chamber and a greenhouse, resulting in a high degree of resistance to lettuce big-vein disease. Transgenic lettuce lines produced in this study could be used as resistant cultivars or parental lines for breeding.
Marschall, Jonas; Lane, Michael A.; Beekmann, Susan E.; Polgreen, Philip; Babcock, Hilary M.
2013-01-01
There is a dearth of guidance on the management of prosthetic joint infections (PJIs), in particular because of the lack of high-quality evidence for optimal antibiotics. Thus, we designed a nine-question survey of current practices and preferences among members of the Emerging Infections Network, a CDC-sponsored network of infectious diseases physicians, which was distributed in May 2012. In total, 556 (47.2%) of 1178 network members responded. As first-line antibiotic choice for MSSA PJI, 59% of responders indicated oxacillin/nafcillin, 33% cefazolin and 7% ceftriaxone; the commonest alternative was cefazolin (46%). For MRSA PJI, 90% preferred vancomycin, 7% daptomycin and 0.8% ceftaroline; the commonest alternative was daptomycin (65%). Antibiotic selection for coagulase-negative staphylococci varied depending on meticillin susceptibility. For staphylococcal PJIs with retained hardware, most providers would add rifampicin. Propionibacterium is usually treated with vancomycin (40%), penicillin (23%) or ceftriaxone (17%). Most responders thought 10–19% of all PJIs were culture-negative. Culture-negative PJIs of the lower extremities are usually treated with a vancomycin/fluoroquinolone combination, and culture-negative shoulder PJIs with vancomycin/ceftriaxone. The most cited criteria for selecting antibiotics were ease of administration and the safety profile. A treatment duration of 6–8 weeks is preferred (by 77% of responders) and is mostly guided by clinical response and inflammatory markers. Ninety-nine percent of responders recommend oral antibiotic suppression (for varying durations) in patients with retained hardware. In conclusion, there is considerable variation in treatment of PJIs both with identified pathogens and those with negative cultures. Future studies should aim to identify optimum treatment strategies. PMID:23312602
Olfactory Bulb Deep Short-Axon Cells Mediate Widespread Inhibition of Tufted Cell Apical Dendrites
LaRocca, Greg
2017-01-01
In the main olfactory bulb (MOB), the first station of sensory processing in the olfactory system, GABAergic interneuron signaling shapes principal neuron activity to regulate olfaction. However, a lack of known selective markers for MOB interneurons has strongly impeded cell-type-selective investigation of interneuron function. Here, we identify the first selective marker of glomerular layer-projecting deep short-axon cells (GL-dSACs) and investigate systematically the structure, abundance, intrinsic physiology, feedforward sensory input, neuromodulation, synaptic output, and functional role of GL-dSACs in the mouse MOB circuit. GL-dSACs are located in the internal plexiform layer, where they integrate centrifugal cholinergic input with highly convergent feedforward sensory input. GL-dSAC axons arborize extensively across the glomerular layer to provide highly divergent yet selective output onto interneurons and principal tufted cells. GL-dSACs are thus capable of shifting the balance of principal tufted versus mitral cell activity across large expanses of the MOB in response to diverse sensory and top-down neuromodulatory input. SIGNIFICANCE STATEMENT The identification of cell-type-selective molecular markers has fostered tremendous insight into how distinct interneurons shape sensory processing and behavior. In the main olfactory bulb (MOB), inhibitory circuits regulate the activity of principal cells precisely to drive olfactory-guided behavior. However, selective markers for MOB interneurons remain largely unknown, limiting mechanistic understanding of olfaction. Here, we identify the first selective marker of a novel population of deep short-axon cell interneurons with superficial axonal projections to the sensory input layer of the MOB. Using this marker, together with immunohistochemistry, acute slice electrophysiology, and optogenetic circuit mapping, we reveal that this novel interneuron population integrates centrifugal cholinergic input with broadly tuned feedforward sensory input to modulate principal cell activity selectively. PMID:28003347
Marker-Based Hierarchical Segmentation and Classification Approach for Hyperspectral Imagery
NASA Technical Reports Server (NTRS)
Tarabalka, Yuliya; Tilton, James C.; Benediktsson, Jon Atli; Chanussot, Jocelyn
2011-01-01
The Hierarchical SEGmentation (HSEG) algorithm, which is a combination of hierarchical step-wise optimization and spectral clustering, has given good performances for hyperspectral image analysis. This technique produces at its output a hierarchical set of image segmentations. The automated selection of a single segmentation level is often necessary. We propose and investigate the use of automatically selected markers for this purpose. In this paper, a novel Marker-based HSEG (M-HSEG) method for spectral-spatial classification of hyperspectral images is proposed. First, pixelwise classification is performed and the most reliably classified pixels are selected as markers, with the corresponding class labels. Then, a novel constrained marker-based HSEG algorithm is applied, resulting in a spectral-spatial classification map. The experimental results show that the proposed approach yields accurate segmentation and classification maps, and thus is attractive for hyperspectral image analysis.
Molecular Markers and Cotton Genetic Improvement: Current Status and Future Prospects
Malik, Waqas; Iqbal, Muhammad Zaffar; Ali Khan, Asif; Qayyum, Abdul; Ali Abid, Muhammad; Noor, Etrat; Qadir Ahmad, Muhammad; Hasan Abbasi, Ghulam
2014-01-01
Narrow genetic base and complex allotetraploid genome of cotton (Gossypium hirsutum L.) is stimulating efforts to avail required polymorphism for marker based breeding. The availability of draft genome sequence of G. raimondii and G. arboreum and next generation sequencing (NGS) technologies facilitated the development of high-throughput marker technologies in cotton. The concepts of genetic diversity, QTL mapping, and marker assisted selection (MAS) are evolving into more efficient concepts of linkage disequilibrium, association mapping, and genomic selection, respectively. The objective of the current review is to analyze the pace of evolution in the molecular marker technologies in cotton during the last ten years into the following four areas: (i) comparative analysis of low- and high-throughput marker technologies available in cotton, (ii) genetic diversity in the available wild and improved gene pools of cotton, (iii) identification of the genomic regions within cotton genome underlying economic traits, and (iv) marker based selection methodologies. Moreover, the applications of marker technologies to enhance the breeding efficiency in cotton are also summarized. Aforementioned genomic technologies and the integration of several other omics resources are expected to enhance the cotton productivity and meet the global fiber quantity and quality demands. PMID:25401149
Selection of a novel CD19 aptamer for targeted delivery of doxorubicin to lymphoma cells.
Hu, Yan; Li, Xiaoou; An, Yacong; Duan, Jinhong; Yang, Xian-Da
2018-06-01
CD19 is overexpressed in most human B cell malignancies and considered an important tumor marker for diagnosis and treatment. Aptamers are oligonucleotides that may potentially serve as tumor-homing ligand for targeted cancer therapy with excellent affinity and specificity. In this study, we selected a novel CD19 aptamer (LC1) that was a 59-nucleotide single strand DNA. The aptamer could bind to recombinant CD19 protein with a K d of 85.4 nM, and had minimal cross reactivity to bovine serum albumin (BSA) or ovalbumin (OVA). Moreover, the aptamer was found capable of binding with the CD19-positive lymphoma cells (Ramos and Raji), but not the CD19-negative cell lines (Jurkat and NB4). An aptamer-doxorubicin complex (Apt-Dox) was also formulated, and selectively delivered doxorubicin to CD19-positive lymphoma cells in vitro . The results indicate that aptamer LC1 can recognize CD19-positive tumor cells and may potentially function as a CD19-targeting ligand.
Asgari, Mojgan; Nabi Maybodi, Mahtab; Abolhasani, Maryam
2016-01-01
Background: Flat urothelial lesions comprise a spectrum of morphologic changes ranging from reactive atypia to carcinoma in situ (CIS). Urothelial dysplasia and CIS are associated with the recurrence and progression of urothelial carcinoma. Distinguishing CIS and dysplasia from reactive atypia based on histolopathogical features alone is often difficult. Using different immunohistochemical markers such as Cytokeratin 20 (CK20), CD44, p53, and Ki-67 is recommended for differential diagnosis. The aim of this study was to evaluate the immunohistochemical pattern of these antibodies to differentiate different flat urothelial lesions. Methods: In this cross- sectional study, three groups of bladder biopsy specimens were evaluated: 20 samples with reactive urothelial lesions, 20 histologically diagnosed as CIS, and 20 morphologically normal samples. Immunohistochemical staining of CK20, p53, CD44 and Ki-67 markers was performed on paraffin-embedded blocks. The groups were compared using chi square test, and the diagnostic value of the markers were evaluated with sensitivity, specificity, positive and negative predictive values. Results: CK20 was full thickness positive in 15 (75%) CIS samples and negative in all samples of the normal and reactive groups (p<0.001); CD44 was positive in 2 (10%) cases of the CIS group and in 17 (85%) of the reactive group; this marker was negative in all the normal samples (p<0.001). P53 was positive in 12 (60%) samples of the CIS group and negative in all samples of the normal and reactive groups (p<0.001). Ki67 was positive in 13 (65%) samples of the CIS group and 1 (5%) sample of the reactive group. This marker was negative in all samples of the normal group (p<0.001). Conclusion: The results of this study revealed that CK20, CD44, P53 and Ki67 are useful in distinguishing CIS from reactive and normal samples. However, they should be used in a panel including at least three markers. Correlation with the morphologic features is necessary. PMID:27579290
Torshabi, Ahmad Esmaili; Nankali, Saber
2016-01-01
In external beam radiotherapy, one of the most common and reliable methods for patient geometrical setup and/or predicting the tumor location is use of external markers. In this study, the main challenging issue is increasing the accuracy of patient setup by investigating external markers location. Since the location of each external marker may yield different patient setup accuracy, it is important to assess different locations of external markers using appropriate selective algorithms. To do this, two commercially available algorithms entitled a) canonical correlation analysis (CCA) and b) principal component analysis (PCA) were proposed as input selection algorithms. They work on the basis of maximum correlation coefficient and minimum variance between given datasets. The proposed input selection algorithms work in combination with an adaptive neuro‐fuzzy inference system (ANFIS) as a correlation model to give patient positioning information as output. Our proposed algorithms provide input file of ANFIS correlation model accurately. The required dataset for this study was prepared by means of a NURBS‐based 4D XCAT anthropomorphic phantom that can model the shape and structure of complex organs in human body along with motion information of dynamic organs. Moreover, a database of four real patients undergoing radiation therapy for lung cancers was utilized in this study for validation of proposed strategy. Final analyzed results demonstrate that input selection algorithms can reasonably select specific external markers from those areas of the thorax region where root mean square error (RMSE) of ANFIS model has minimum values at that given area. It is also found that the selected marker locations lie closely in those areas where surface point motion has a large amplitude and a high correlation. PACS number(s): 87.55.km, 87.55.N PMID:27929479
ERP markers of target selection discriminate children with high vs. low working memory capacity.
Shimi, Andria; Nobre, Anna Christina; Scerif, Gaia
2015-01-01
Selective attention enables enhancing a subset out of multiple competing items to maximize the capacity of our limited visual working memory (VWM) system. Multiple behavioral and electrophysiological studies have revealed the cognitive and neural mechanisms supporting adults' selective attention of visual percepts for encoding in VWM. However, research on children is more limited. What are the neural mechanisms involved in children's selection of incoming percepts in service of VWM? Do these differ from the ones subserving adults' selection? Ten-year-olds and adults used a spatial arrow cue to select a colored item for later recognition from an array of four colored items. The temporal dynamics of selection were investigated through EEG signals locked to the onset of the memory array. Both children and adults elicited significantly more negative activity over posterior scalp locations contralateral to the item to-be-selected for encoding (N2pc). However, this activity was elicited later and for longer in children compared to adults. Furthermore, although children as a group did not elicit a significant N2pc during the time-window in which N2pc was elicited in adults, the magnitude of N2pc during the "adult time-window" related to their behavioral performance during the later recognition phase of the task. This in turn highlights how children's neural activity subserving attention during encoding relates to better subsequent VWM performance. Significant differences were observed when children were divided into groups of high vs. low VWM capacity as a function of cueing benefit. Children with large cue benefits in VWM capacity elicited an adult-like contralateral negativity following attentional selection of the to-be-encoded item, whereas children with low VWM capacity did not. These results corroborate the close coupling between selective attention and VWM from childhood and elucidate further the attentional mechanisms constraining VWM performance in children.
Marker-Assisted Introgression in Backcross Breeding Programs
Visscher, P. M.; Haley, C. S.; Thompson, R.
1996-01-01
The efficiency of marker-assisted introgression in backcross populations derived from inbred lines was investigated by simulation. Background genotypes were simulated assuming that a genetic model of many genes of small effects in coupling phase explains the observed breed difference and variance in backcross populations. Markers were efficient in introgression backcross programs for simultaneously introgressing an allele and selecting for the desired genomic background. Using a marker spacing of 10-20 cM gave an advantage of one to two backcross generations selection relative to random or phenotypic selection. When the position of the gene to be introgressed is uncertain, for example because its position was estimated from a trait gene mapping experiment, a chromosome segment should be introgressed that is likely to include the allele of interest. Even for relatively precisely mapped quantitative trait loci, flanking markers or marker haplotypes should cover ~10-20 cM around the estimated position of the gene, to ensure that the allele frequency does not decline in later backcross generations. PMID:8978075
Recent advances in development of marker-free transgenic plants: regulation and biosafety concern.
Tuteja, Narendra; Verma, Shiv; Sahoo, Ranjan Kumar; Raveendar, Sebastian; Reddy, I N Bheema Lingeshwara
2012-03-01
During the efficient genetic transformation of plants with the gene of interest, some selectable marker genes are also used in order to identify the transgenic plant cells or tissues. Usually, antibiotic- or herbicide-selective agents and their corresponding resistance genes are used to introduce economically valuable genes into crop plants. From the biosafety authority and consumer viewpoints, the presence of selectable marker genes in released transgenic crops may be transferred to weeds or pathogenic microorganisms in the gastrointestinal tract or soil, making them resistant to treatment with herbicides or antibiotics, respectively. Sexual crossing also raises the problem of transgene expression because redundancy of transgenes in the genome may trigger homology-dependent gene silencing. The future potential of transgenic technologies for crop improvement depends greatly on our abilities to engineer stable expression of multiple transgenic traits in a predictable fashion and to prevent the transfer of undesirable transgenic material to non-transgenic crops and related species. Therefore, it is now essential to develop an efficient marker-free transgenic system. These considerations underline the development of various approaches designed to facilitate timely elimination of transgenes when their function is no longer needed. Due to the limiting number of available selectable marker genes, in future the stacking of transgenes will be increasingly desirable. The production of marker-free transgenic plants is now a critical requisite for their commercial deployment and also for engineering multiple and complex trait. Here we describe the current technologies to eliminate the selectable marker genes (SMG) in order to develop marker-free transgenic plants and also discuss the regulation and biosafety concern of genetically modified (GM) crops.
Midlife women, bone health, vegetables, herbs and fruit study. The Scarborough Fair study protocol.
Gunn, Caroline A; Weber, Janet L; Kruger, Marlena C
2013-01-10
Bone loss is accelerated in middle aged women but increased fruit/vegetable intake positively affects bone health by provision of micronutrients essential for bone formation, buffer precursors which reduce acid load and phytochemicals affecting inflammation and oxidative stress. Animal studies demonstrated bone resorption inhibiting properties of specific vegetables, fruit and herbs a decade ago. To increase fruit/vegetable intake in post menopausal women to 9 servings/day using a food specific approach to significantly reduce dietary acid load and include specific vegetables, fruit and herbs with bone resorbing inhibiting properties to assess effect on bone turnover, metabolic and inflammatory markers. The Scarborough Fair Study is a randomised active comparator controlled multi centre trial. It aimed to increase fruit and vegetable intake in 100 post menopausal women from ≤ 5 servings/day to ≥ 9 servings/day for 3 months. The women in the dietary intervention were randomly assigned to one of the two arms of the study. Both groups consumed ≥ 9 servings/day of fruit/vegetables and selected herbs but the diet of each group emphasised different fruit/vegetables/herbs with one group (B) selecting from a range of vegetables, fruit and culinary herbs with bone resorbing inhibiting properties. 50 women formed a negative control group (Group C usual diet). Primary outcome variables were plasma bone markers assessed at baseline, 6 weeks and 12 weeks. Secondary outcome variables were plasma inflammation and metabolic markers and urinary electrolytes (calcium, magnesium, potassium and sodium) assessed at baseline and 12 weeks. Dietary intake and urine pH change also were outcome variables. The dietary change was calculated with 3 day diet diaries and a 24 hour recall. Intervention participants kept a twice weekly record of fruit, vegetable and herb intake and urine pH. This study will provide information on midlife women's bone health and how a dietary intervention increasing fruit and vegetable/herb intake affects bone, inflammatory and metabolic markers and urinary electrolyte excretion. It assesses changes in nutrient intake, estimated dietary acid load and sodium: potassium ratios. The study also explores whether specific fruit/vegetables and herbs with bone resorbing properties has an effect on bone markers. ACTRN 12611000763943.
Viatte, Sebastien; Massey, Jonathan; Bowes, John; Duffus, Kate; Eyre, Stephen; Barton, Anne; Loughlin, John; Arden, Nigel; Birrell, Fraser; Carr, Andrew; Deloukas, Panos; Doherty, Michael; McCaskie, Andrew W.; Ollier, William E. R.; Rai, Ashok; Ralston, Stuart H.; Spector, Tim D.; Valdes, Ana M.; Wallis, Gillian A.; Wilkinson, J. Mark; Zeggini, Eleftheria
2016-01-01
Objective Genetic polymorphisms within the HLA region explain only a modest proportion of anti–cyclic citrullinated peptide (anti‐CCP)–negative rheumatoid arthritis (RA) heritability. However, few non‐HLA markers have been identified so far. This study was undertaken to replicate the associations of anti‐CCP–negative RA with non‐HLA genetic polymorphisms demonstrated in a previous study. Methods The Rheumatoid Arthritis Consortium International densely genotyped 186 autoimmune‐related regions in 3,339 anti‐CCP–negative RA patients and 15,870 controls across 6 different populations using the Illumina ImmunoChip array. We performed a case–control replication study of the anti‐CCP–negative markers with the strongest associations in that discovery study, in an independent cohort of anti‐CCP–negative UK RA patients. Individuals from the arcOGEN Consortium and Wellcome Trust Case Control Consortium were used as controls. Genotyping in cases was performed using Sequenom MassArray technology. Genome‐wide data from controls were imputed using the 1000 Genomes Phase I integrated variant call set release version 3 as a reference panel. Results After genotyping and imputation quality control procedures, data were available for 15 non‐HLA single‐nucleotide polymorphisms in 1,024 cases and 6,348 controls. We confirmed the known markers ANKRD55 (meta‐analysis odds ratio [OR] 0.80; P = 2.8 × 10−13) and BLK (OR 1.13; P = 7.0 × 10−6) and identified new and specific markers of anti‐CCP–negative RA (prolactin [PRL] [OR 1.13; P = 2.1 × 10−6] and NFIA [OR 0.85; P = 2.5 × 10−6]). Neither of these loci is associated with other common, complex autoimmune diseases. Conclusion Anti‐CCP–negative RA and anti‐CCP–positive RA are genetically different disease subsets that only partially share susceptibility factors. Genetic polymorphisms located near the PRL and NFIA genes represent examples of genetic susceptibility factors specific for anti‐CCP–negative RA. PMID:26895230
Affective traits link to reliable neural markers of incentive anticipation.
Wu, Charlene C; Samanez-Larkin, Gregory R; Katovich, Kiefer; Knutson, Brian
2014-01-01
While theorists have speculated that different affective traits are linked to reliable brain activity during anticipation of gains and losses, few have directly tested this prediction. We examined these associations in a community sample of healthy human adults (n=52) as they played a Monetary Incentive Delay task while undergoing functional magnetic resonance imaging (FMRI). Factor analysis of personality measures revealed that subjects independently varied in trait Positive Arousal and trait Negative Arousal. In a subsample (n=14) retested over 2.5years later, left nucleus accumbens (NAcc) activity during anticipation of large gains (+$5.00) and right anterior insula activity during anticipation of large losses (-$5.00) showed significant test-retest reliability (intraclass correlations>0.50, p's<0.01). In the full sample (n=52), trait Positive Arousal correlated with individual differences in left NAcc activity during anticipation of large gains, while trait Negative Arousal correlated with individual differences in right anterior insula activity during anticipation of large losses. Associations of affective traits with neural activity were not attributable to the influence of other potential confounds (including sex, age, wealth, and motion). Together, these results demonstrate selective links between distinct affective traits and reliably-elicited activity in neural circuits associated with anticipation of gain versus loss. The findings thus reveal neural markers for affective dimensions of healthy personality, and potentially for related psychiatric symptoms. © 2013. Published by Elsevier Inc. All rights reserved.
Affective traits link to reliable neural markers of incentive anticipation
Wu, Charlene C.; Samanez-Larkin, Gregory R.; Katovich, Kiefer; Knutson, Brian
2013-01-01
While theorists have speculated that different affective traits are linked to reliable brain activity during anticipation of gains and losses, few have directly tested this prediction. We examined these associations in a community sample of healthy human adults (n = 52) as they played a Monetary Incentive Delay Task while undergoing functional magnetic resonance imaging (FMRI). Factor analysis of personality measures revealed that subjects independently varied in trait Positive Arousal and Negative Arousal. In a subsample (n = 14) retested over 2.5 years later, left nucleus accumbens (NAcc) activity during anticipation of large gains (+$5.00) and right anterior insula activity during anticipation of large losses (−$5.00) showed significant test-retest reliability (intraclass correlations > 0.50, p’s < 0.01). In the full sample (n = 52), trait Positive Arousal correlated with individual differences in left NAcc activity during anticipation of large gains, while trait Negative Arousal correlated with individual differences in right anterior insula activity during anticipation of large losses. Associations of affective traits with neural activity were not attributable to the influence of other potential confounds (including sex, age, wealth, and motion). Together, these results demonstrate selective links between distinct affective traits and reliably-elicited activity in neural circuits associated with anticipation of gain versus loss. The findings thus reveal neural markers for affective dimensions of healthy personality, and potentially for related psychiatric symptoms. PMID:24001457
Zhu, Jianguo; Pan, Cong; Jiang, Jun; Deng, Mingsen; Gao, Hengjun; Men, Bozhao; McClelland, Michael; Mercola, Dan; Zhong, Wei-De; Jia, Zhenyu
2015-01-01
We previously analyzed human prostate tissue containing stroma near to tumor and from cancer-negative tissues of volunteers. Over 100 candidate gene expression differences were identified and used to develop a classifier that could detect nearby tumor with an accuracy of 97% (sensitivity = 98% and specificity = 88%) based on 364 independent test cases from primarily European American cases. These stroma-based gene signatures have the potential to identify cancer patients among those with negative biopsies. In this study, we used prostate tissues from Chinese cases to validate six of these markers (CAV1, COL4A2, HSPB1, ITGB3, MAP1A and MCAM). In validation by real-time PCR, four genes (COL4A2, HSPB1, ITGB3, and MAP1A) demonstrated significantly lower expression in tumor-adjacent stroma compared to normal stroma (p value ≤ 0.05). Next, we tested whether these expression differences could be extended to the protein level. In IHC assays, all six selected proteins showed lower expression in tumor-adjacent stroma compared to the normal stroma, of which COL4A2, HSPB1 and ITGB3 showed significant differences (p value ≤ 0.05). These results suggest that biomarkers for diagnosing prostate cancer based on tumor microenvironment may be applicable across multiple racial groups. PMID:26158290
A Tightly Regulated Genetic Selection System with Signaling-Active Alleles of Phytochrome B.
Hu, Wei; Lagarias, J Clark
2017-01-01
Selectable markers derived from plant genes circumvent the potential risk of antibiotic/herbicide-resistance gene transfer into neighboring plant species, endophytic bacteria, and mycorrhizal fungi. Toward this goal, we have engineered and validated signaling-active alleles of phytochrome B (eYHB) as plant-derived selection marker genes in the model plant Arabidopsis (Arabidopsis thaliana). By probing the relationship of construct size and induction conditions to optimal phenotypic selection, we show that eYHB-based alleles are robust substitutes for antibiotic/herbicide-dependent marker genes as well as surprisingly sensitive reporters of off-target transgene expression. © 2017 American Society of Plant Biologists. All Rights Reserved.
A Tightly Regulated Genetic Selection System with Signaling-Active Alleles of Phytochrome B1[OPEN
2017-01-01
Selectable markers derived from plant genes circumvent the potential risk of antibiotic/herbicide-resistance gene transfer into neighboring plant species, endophytic bacteria, and mycorrhizal fungi. Toward this goal, we have engineered and validated signaling-active alleles of phytochrome B (eYHB) as plant-derived selection marker genes in the model plant Arabidopsis (Arabidopsis thaliana). By probing the relationship of construct size and induction conditions to optimal phenotypic selection, we show that eYHB-based alleles are robust substitutes for antibiotic/herbicide-dependent marker genes as well as surprisingly sensitive reporters of off-target transgene expression. PMID:27881727
Marker-assisted selection in plant breeding for salinity tolerance.
Ashraf, M; Akram, N A; Mehboob-Ur-Rahman; Foolad, M R
2012-01-01
Marker-assisted selection (MAS) is the process of using morphological, biochemical, or DNA markers as indirect selection criteria for selecting agriculturally important traits in crop breeding. This process is used to improve the effectiveness or efficiency of selection for the traits of interest in breeding programs. The significance of MAS as a tool for crop improvement has been extensively investigated in different crop -species and for different traits. The use of MAS for manipulating simple/qualitative traits is straightforward and has been well reported. However, MAS for the improvement of complex/polygenic traits, including plant tolerance/resistance to abiotic stresses, is more complicated, although its usefulness has been recognized. With the recent advances in marker technology, including high-throughput genotyping of plants, together with the development of nested association mapping populations, it is expected that the utility of MAS for breeding for stress tolerance traits will increase. In this chapter, we describe the basic procedure for using MAS in crop breeding for salt tolerance.
USDA-ARS?s Scientific Manuscript database
Selection on important genetic markers can improve estimates of additive and dominance association effects. A composite population of beef cattle was selected for intermediate frequencies of myostatin (GDF8) F94L and µ-calpain (CAPN1) polymorphisms. Important additive associations of the GDF8 locu...
Financial feasibility of marker-aided selection in Douglas-fir.
G.R. Johnson; N.C. Wheeler; S.H. Strauss
2000-01-01
The land area required for a marker-aided selection (MAS) program to break-even (i.e., have equal costs and benefits) was estimated using computer simulation for coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the Pacific Northwestern United States. We compared the selection efficiency obtained when using an index that included the...
Selection of chemical markers for the quality control of medicinal plants of the genus Cecropia.
Rivera-Mondragón, Andrés; Ortíz, Orlando O; Bijttebier, Sebastiaan; Vlietinck, Arnold; Apers, Sandra; Pieters, Luc; Caballero-George, Catherina
2017-12-01
Several Cecropia (Cecropiaceae) species are traditionally used in Latin America for the treatment of a variety of diseases including diabetes, arterial hypertension, asthma, bronchitis, anxiety, and inflammation. At present, a number of commercial products based on these plants have been introduced into the market with very little information on methods for guaranteeing their quality and safety. This work proposes potential chemical markers for the quality control of the raw materials of Cecropia obtusifolia Bertol., Cecropia peltata L., Cecropia glaziovii Snethl., Cecropia pachystachya Trécul, and Cecropia hololeuca Miq. The Herbal Chemical Marker Ranking System (Herb MaRS) developed by the National Institute of Complementary Medicine (NICM) at the University of Western Sydney was used for selecting chemical markers for the quality control of selected medicinal species of Cecropia. This review covers the period from 1982 to 2016. Chlorogenic acid, flavonoidal glycosides (orientin, isoorientin, vitexin, isovitexin, and rutin), catechin, epicatechin, procyanidins (B2, B5, and C1), steroids (β-sitosterol), and triterpenoids (α-amyrin, pomolic, tormentic and ursolic acids) were selected as chemical markers for the quality control of the leaves. It is necessary to establish comprehensive standards for guaranteeing quality, safety and efficacy of herbal drugs. The selection of adequate chemical markers for quality control purposes requires a good knowledge about the chemical composition of medicinal plants and their associated biological properties. To the best of our knowledge this review article is the first to address the identification and quantitative determination of the chemical markers for the genus Cecropia.
Morgan, Angela J; Guillen, Cristina; Symon, Fiona A; Birring, Surinder S; Campbell, James J; Wardlaw, Andrew J
2008-01-01
Expressions of activation markers have been described on the surface of T cells in the blood and the lung in both health and disease. We have studied the distribution of activation markers on human lung T cells and have found that only certain populations exist. Importantly, the presence or absence of some markers appears to predict those of others, in particular cells which express CD103 also express CD49a and CD69, whereas cells which do not express CD69 also do not express CD49a or CD103. In view of the paucity of activation marker expression in the peripheral blood, we have hypothesised that these CD69+, CD49a+, and CD103+ (triple positive) cells are retained in the lung, possess effector function (IFNgamma secretion) and express particular chemokine receptors which allow them to be maintained in this environment. We have found that the ability of the triple negative cells to secrete IFNgamma is significantly less than the triple positive cells, suggesting that the expression of activation markers can highlight a highly specialised effector cell. We have studied the expression of 14 chemokine receptors and have found that the most striking difference between the triple negative cells and the triple positive cells is the expression of CXCR6 with 12.8+/-9.8% of triple negative cells expressing CXCR6 compared to 89.5+/-5.5% of triple positive cells. We propose therefore that CXCR6 may play an important role in the retention of T cells within the lung.
Aoufi, S; Pascasio, J M; Sousa, J M; Sayago, M; Ferrer, M T; Gómez-Delgado, E; De la Cruz, M D; Alamo, J M; Gómez-Bravo, M A; Bernardos, A; Márquez, J L
2008-11-01
Vaccination against hepatitis A virus (HAV) and hepatitis B virus (HBV) is generally recommended for patients with chronic liver disease and those evaluated for liver transplantation in the absence of immunity. HAV and HBV infections after liver transplantation are frequent and associated with a worse prognosis. The data suggest that the number of patients with chronic liver disease without naturally acquired immunity against HAV and HBV is substantial, and that new vaccination strategies are needed. The aim of this study was to determine the level of immunity from hepatitis A and B infections and the need for HBV and HAV vaccination among cirrhotic patients evaluated for liver transplantation. We studied HBV and HAV serological markers (HbsAg, anti-HBc, anti-HBs, IgG anti-HAV) in 451 cirrhotic patients evaluated for liver transplantation to investigate the association with gender, age, and etiology of cirrhosis. Negative HBV markers were observed in 57% of patients with 43% displaying one positive HBV marker: HBsAg (+), 9.5%; anti-HBc (+)/anti-HBs (-), 11.5%; anti-HBc (-)/anti-HBs(+), 4.2%; anti-HBc(+)/anti-HBs(+), 17.7%. HBV vaccine indication established in 68.5% of patients was greater among women and hepatitis C virus-negative patients. No differences were observed in age or cause of cirrhosis. HAV vaccination indicated in 6.7% of patients (IgG anti-HVA-negative) was greater among patients with negative HBV markers (9.3% vs 3.3%, P = .018) and younger patients (25.3% of patients =45 years). In conclusion, there are frequent indication, for HBV vaccine among cirrhotic patients evaluated for liver transplantation, as is time for HAV vaccine, especially among patients younger than 45 years of age.
Fernandez, Ronan; Berro, Julien
2017-01-01
Fission yeast is a powerful model organism that has provided insights into important cellular processes thanks to the ease of its genome editing by homologous recombination. However, creation of strains with a large number of targeted mutations or containing plasmids has been challenging because only a very small number of selection markers is available in Schizosaccharomyces pombe. In this paper, we identify two fission yeast fluoride exporter channels (Fex1p and Fex2p) and describe the development of a new strategy using Fex1p as a selection marker for transformants in rich media supplemented with fluoride. To our knowledge this is the first positive selection marker identified in S. pombe that does not use auxotrophy or drug resistance and that can be used for plasmids transformation or genomic integration in rich media. We illustrate the application of our new marker by significantly accelerating the protocol for genome edition using CRISPR/Cas9 in S. pombe. PMID:27327046
Murtezaoglu, Afsin Rahman; Gucer, Hasan
In this study, we compared the diagnostic value of TROP-2 expression in distinguishing between benign and malignant thyroid lesions to those of HBME-1, CK19 and galectin-3. We selected 102 cases from our archive including 20 normal thyroid tissues, 23 follicular nodular diseases, 17 follicular adenomas, 20 follicular variant papillary carcinomas and 22 classical variant papillary carcinomas. Tissue microarrays constructed from these cases were immunohistochemically analyzed with HBME-1, CK19, galectin-3 and TROP-2. Respectively 73.8%, 83.3%, 69% and 50% of all papillary carcinomas were positive with HBME-1, CK19, galectin-3 and TROP-2. CK19 was positive respectively by 100%, 43.5% and 35.3% in cases of normal thyroid, follicular nodular diseases and follicular adenoma, while the other markers were negative. In distinguishing benign and malignant lesions, which constitutes this study, HBME-1, CK19, galectin-3 and TROP-2 were statistically significant (p < 0.001). In distinguishing cases of follicular variant papillary carcinoma from follicular nodular diseases and follicular adenoma, HBME-1 and galectin-3 were statistically significant (p < 0.001). Consequently, in this study, we found that all immunohistochemical markers were effective in distinguishing benign and malignant thyroid lesions. In determining malignancy, HBME-1 had the highest diagnostic accuracy, while CK19 was the most sensitive marker. The sensitivity increased when the markers were used together.
Rubinstein, M; Japón, M A; Low, M J
1993-06-11
The introduction of small mutations instead of null alleles into the mouse genome has broad applications to the study of protein structure-function relationships and the creation of animal models of human genetic diseases. To test a simple mutational strategy we designed a targeting vector for the mouse proopiomelanocortin (POMC) gene containing a single nucleotide insertion that converts the initial tyrosine codon of beta-endorphin 1-31 to a premature translational termination codon and introduces a unique Hpal endonuclease restriction site. The targeting vector also contains a neo cassette immediately 3' to the last POMC exon and a herpes simplex virus thymidine kinase cassette to allow positive and negative selection. Homologous recombination occurred at a frequency of 1/30 clones of electroporated embryonic stem cells selected in G418 and gancyclovir. 10/11 clones identified initially by a polymerase chain reaction (PCR) strategy had the predicted structure without evidence of concatemer formation by Southern blot analysis. We used a combination of Hpa I digestion of PCR amplified fragments and direct nucleotide sequencing to further confirm that the point mutation was retained in 9/10 clones. The POMC gene was transcriptionally silent in embryonic stem cells and the targeted allele was not activated by the downstream phosphoglycerate kinase-1 promoter that transcribed the neo gene. Under the electroporation conditions used, we have demonstrated that a point mutation can be introduced with high efficiency and precision into the POMC gene using a replacement type vector containing a retained selectable marker without affecting expression of the allele in the embryonic stem cells. A similar strategy may be useful for a wide range of genes.
Rubinstein, M; Japón, M A; Low, M J
1993-01-01
The introduction of small mutations instead of null alleles into the mouse genome has broad applications to the study of protein structure-function relationships and the creation of animal models of human genetic diseases. To test a simple mutational strategy we designed a targeting vector for the mouse proopiomelanocortin (POMC) gene containing a single nucleotide insertion that converts the initial tyrosine codon of beta-endorphin 1-31 to a premature translational termination codon and introduces a unique Hpal endonuclease restriction site. The targeting vector also contains a neo cassette immediately 3' to the last POMC exon and a herpes simplex virus thymidine kinase cassette to allow positive and negative selection. Homologous recombination occurred at a frequency of 1/30 clones of electroporated embryonic stem cells selected in G418 and gancyclovir. 10/11 clones identified initially by a polymerase chain reaction (PCR) strategy had the predicted structure without evidence of concatemer formation by Southern blot analysis. We used a combination of Hpa I digestion of PCR amplified fragments and direct nucleotide sequencing to further confirm that the point mutation was retained in 9/10 clones. The POMC gene was transcriptionally silent in embryonic stem cells and the targeted allele was not activated by the downstream phosphoglycerate kinase-1 promoter that transcribed the neo gene. Under the electroporation conditions used, we have demonstrated that a point mutation can be introduced with high efficiency and precision into the POMC gene using a replacement type vector containing a retained selectable marker without affecting expression of the allele in the embryonic stem cells. A similar strategy may be useful for a wide range of genes. Images PMID:8392702
Gothard, David; Tare, Rahul S; Mitchell, Peter D; Dawson, Jonathan I; Oreffo, Richard O C
2011-04-07
Skeletal stem cells (SSCs) show great capacity for bone and cartilage repair however, current in vitro cultures are heterogeneous displaying a hierarchy of differentiation potential. SSCs represent the diminutive true multipotent stem cell fraction of bone marrow mononuclear cell (BMMNC) populations. Endeavours to isolate SSCs have generated a multitude of separation methodologies. SSCs were first identified and isolated by their ability to adhere to culture plastic. Once isolated, further separation is achieved via culture in selective or conditioned media (CM). Indeed, preferential SSC growth has been demonstrated through selective in vitro culture conditions. Other approaches have utilised cell morphology (size and shape) as selection criteria. Studies have also targeted SSCs based on their preferential adhesion to specified compounds, individually or in combination, on both macro and microscale platforms. Nevertheless, most of these methods which represent macroscale function with relatively high throughput, yield insufficient purity. Consequently, research has sought to downsize isolation methodologies to the microscale for single cell analysis. The central approach is identification of the requisite cell populations of SSC-specific surface markers that can be targeted for isolation by either positive or negative selection. SELEX and phage display technology provide apt means to sift through substantial numbers of candidate markers. In contrast, single cell analysis is the paramount advantage of microfluidics, a relatively new field for cell biology. Here cells can be separated under continuous or discontinuous flow according to intrinsic phenotypic and physicochemical properties. The combination of macroscale quantity with microscale specificity to generate robust high-throughput (HT) technology for pure SSC sorting, isolation and enrichment offers significant implications therein for skeletal regenerative strategies as a consequence of lab on chip derived methodology.
Ma, Anlun; Jiang, Li; Song, Lijun; Hu, Yanxin; Dun, Hao; Daloze, Pierre; Yu, Yonglin; Jiang, Jianyuan; Zafarullah, Muhammad; Chen, Huifang
2013-07-01
Articular cartilage defects are commonly associated with trauma, inflammation and osteoarthritis. Mesenchymal stem cell (MSC)-based therapy is a promising novel approach for repairing articular cartilage. Direct intra-articular injection of uncommitted MSCs does not regenerate high-quality cartilage. This study explored utilization of a new three-dimensional, selected chondrogenic clonal MSC-loaded monkey acellular dermal matrix (MSC-ADM) scaffold to repair damaged cartilage in an experimental model of knee joint cartilage defect in Cynomolgus monkeys. MSCs were characterized for cell size, cell yield, phenotypes, proliferation and chondrogenic differentiation capacity. Chondrogenic differentiation assays were performed at different MSC passages by sulfated glycosaminoglycans (sGAG), collagen, and fluorescence activated cell sorter (FACS) analysis. Selected chondrogenic clonal MSCs were seeded onto ADM scaffold with the sandwich model and MSC-loaded ADM grafts were analyzed by confocal microscopy and scanning electron microscopy. Cartilage defects were treated with normal saline, clonal MSCs and clonal MSC-ADM grafts, respectively. The clinical parameters, and histological and immunohistochemical examinations were evaluated at weeks 8, 16, 24 post-treatment, respectively. Polyclonal and clonal MSCs could differentiate into the chondrogenic lineage after stimulation with suitable chondrogenic factors. They expressed mesenchymal markers and were negative for hematopoietic markers. Articular cartilage defects were considerably improved and repaired by selected chondrogenic clonal MSC-based treatment, particularly, in MSC-ADM-treated group. The histological scores in MSC-ADM-treated group were consistently higher than those of other groups. Our results suggest that selected chondrogenic clonal MSC-loaded ADM grafts could improve the cartilage lesions in Cynomolgus monkey model, which may be applicable for repairing similar human cartilage defects. Copyright © 2013 Elsevier B.V. All rights reserved.
Laurie, Cathy C.; Chasalow, Scott D.; LeDeaux, John R.; McCarroll, Robert; Bush, David; Hauge, Brian; Lai, Chaoqiang; Clark, Darryl; Rocheford, Torbert R.; Dudley, John W.
2004-01-01
In one of the longest-running experiments in biology, researchers at the University of Illinois have selected for altered composition of the maize kernel since 1896. Here we use an association study to infer the genetic basis of dramatic changes that occurred in response to selection for changes in oil concentration. The study population was produced by a cross between the high- and low-selection lines at generation 70, followed by 10 generations of random mating and the derivation of 500 lines by selfing. These lines were genotyped for 488 genetic markers and the oil concentration was evaluated in replicated field trials. Three methods of analysis were tested in simulations for ability to detect quantitative trait loci (QTL). The most effective method was model selection in multiple regression. This method detected ∼50 QTL accounting for ∼50% of the genetic variance, suggesting that >50 QTL are involved. The QTL effect estimates are small and largely additive. About 20% of the QTL have negative effects (i.e., not predicted by the parental difference), which is consistent with hitchhiking and small population size during selection. The large number of QTL detected accounts for the smooth and sustained response to selection throughout the twentieth century. PMID:15611182
Li, Y M; Bai, C Y; Niu, W P; Yu, H; Yang, R J; Yan, S Q; Zhang, J Y; Zhang, M J; Zhao, Z H
2015-09-28
Microsatellite markers are widely and evenly distributed, and are highly polymorphic. Rapid and convenient detection through automated analysis means that microsatellite markers are widely used in the construction of plant and animal genetic maps, in quantitative trait loci localization, marker-assisted selection, identification of genetic relationships, and genetic diversity and phylogenetic tree construction. However, few microsatellite markers remain to be isolated. We used streptavidin magnetic beads to affinity-capture and construct a (CA)n microsatellite DNA-enriched library from sika deer. We selected sequences containing more than six repeats to design primers. Clear bands were selected, which were amplified using non-specific primers following PCR amplification to screen polymorphisms in a group of 65 unrelated sika deer. The positive clone rate reached 82.9% by constructing the enriched library, and we then selected positive clones for sequencing. There were 395 sequences with CA repeats, and the CA repeat number was 4-105. We selected sequences containing more than six repeats to design primers, of which 297 pairs were designed. We next selected clear bands and used non-specific primers to amplify following PCR amplification. In total, 245 pairs of primers were screened. We then selected 50 pairs of primers to randomly screen for polymorphisms. We detected 47 polymorphic and 3 monomorphic loci in 65 unrelated sika deer. These newly isolated and characterized microsatellite loci can be used to construct genetic maps and for lineage testing in deer. In addition, they can be used for comparative genomics between Cervidae species.
Marinaccio, Christian; Giudice, Giuseppe; Nacchiero, Eleonora; Robusto, Fabio; Opinto, Giuseppina; Lastilla, Gaetano; Maiorano, Eugenio; Ribatti, Domenico
2016-08-01
The presence of interval sentinel lymph nodes in melanoma is documented in several studies, but controversies still exist about the management of these lymph nodes. In this study, an immunohistochemical evaluation of tumor cell proliferation and neo-angiogenesis has been performed with the aim of establishing a correlation between these two parameters between positive and negative interval sentinel lymph nodes. This retrospective study reviewed data of 23 patients diagnosed with melanoma. Bioptic specimens of interval sentinel lymph node were retrieved, and immunohistochemical reactions on tissue sections were performed using Ki67 as a marker of proliferation and CD31 as a blood vessel marker for the study of angiogenesis. The entire stained tissue sections for each case were digitized using Aperio Scanscope Cs whole-slide scanning platform and stored as high-resolution images. Image analysis was carried out on three selected fields of equal area using IHC Nuclear and Microvessel analysis algorithms to determine positive Ki67 nuclei and vessel number. Patients were divided into positive and negative interval sentinel lymph node groups, and the positive interval sentinel lymph node group was further divided into interval positive with micrometastasis and interval positive with macrometastasis subgroups. The analysis revealed a significant difference between positive and negative interval sentinel lymph nodes in the percentage of Ki67-positive nuclei and mean vessel number suggestive of an increased cellular proliferation and angiogenesis in positive interval sentinel lymph nodes. Further analysis in the interval positive lymph node group showed a significant difference between micro- and macrometastasis subgroups in the percentage of Ki67-positive nuclei and mean vessel number. Percentage of Ki67-positive nuclei was increased in the macrometastasis subgroup, while mean vessel number was increased in the micrometastasis subgroup. The results of this study suggest that the correlation between tumor cell proliferation and neo-angiogenesis in interval sentinel lymph nodes in melanoma could be used as a good predictive marker to distinguish interval positive sentinel lymph nodes with micrometastasis from interval positive lymph nodes with macrometastasis subgroups.
Darvasi, A.; Soller, M.
1994-01-01
Selective genotyping is a method to reduce costs in marker-quantitative trait locus (QTL) linkage determination by genotyping only those individuals with extreme, and hence most informative, quantitative trait values. The DNA pooling strategy (termed: ``selective DNA pooling'') takes this one step further by pooling DNA from the selected individuals at each of the two phenotypic extremes, and basing the test for linkage on marker allele frequencies as estimated from the pooled samples only. This can reduce genotyping costs of marker-QTL linkage determination by up to two orders of magnitude. Theoretical analysis of selective DNA pooling shows that for experiments involving backcross, F(2) and half-sib designs, the power of selective DNA pooling for detecting genes with large effect, can be the same as that obtained by individual selective genotyping. Power for detecting genes with small effect, however, was found to decrease strongly with increase in the technical error of estimating allele frequencies in the pooled samples. The effect of technical error, however, can be markedly reduced by replication of technical procedures. It is also shown that a proportion selected of 0.1 at each tail will be appropriate for a wide range of experimental conditions. PMID:7896115
Martinez, Maria Carmela; Kok, Chee Choy; Baleriola, Cristina; Robertson, Peter; Rawlinson, William D
2015-01-01
Occult hepatitis B infection (OBI) is manifested by presence of very low levels (<200IU/mL) of Hepatitis B viral DNA (HBV DNA) in the blood and the liver while exhibiting undetectable HBV surface antigen (HBsAg). The molecular mechanisms underlying this occurrence are still not completely understood. This study investigated the prevalence of OBI in a high-risk Australian population and compared the HBV S gene sequences of our cohort with reference sequences. Serum from HBV DNA positive, HBsAg negative, and hepatitis B core antibody (anti-HBc) positive patients (study cohort) were obtained from samples tested at SEALS Serology Laboratory using the Abbott Architect, as part of screening and diagnostic testing. From a total of 228,108 samples reviewed, 1,451 patients were tested for all three OBI markers. Only 10 patients (0.69%) out of the 1,451 patients were found to fit the selection criteria for OBI. Sequence analysis of the HBV S gene from 5 suspected OBI infected patients showed increased sequence variability in the 'a' epitope of the major hydrophilic region compared to reference sequences. In addition, a total of eight consistent nucleotide substitutions resulting in seven amino acid changes were observed, and three patients had truncated S gene sequence. These mutations appeared to be stable and may result in alterations in HBsAg conformation. These may negatively impact the affinity of hepatitis B surface antibody (anti-HBs) and may explain the false negative results in serological HBV diagnosis. These changes may also enable the virus to persist in the liver by evading immune surveillance. Further studies on a bigger cohort are required to determine whether these amino acid variations have been acquired in the process of immune escape and serve as markers of OBI.
Uva, Paolo; Cossu-Rocca, Paolo; Loi, Federica; Pira, Giovanna; Murgia, Luciano; Orrù, Sandra; Floris, Matteo; Muroni, Maria Rosaria; Sanges, Francesca; Carru, Ciriaco; Angius, Andrea; De Miglio, Maria Rosaria
2018-01-01
The clinical and genetic heterogeneity of Triple Negative Breast Cancer (TNBC) and the lack of unambiguous molecular targets contribute to the inadequacy of current therapeutic options for these variants. MicroRNAs (miRNA) are a class of small highly conserved regulatory endogenous non-coding RNA, which can alter the expression of genes encoding proteins and may play a role in the dysregulation of cellular pathways. Our goal was to improve the knowledge of the molecular pathogenesis of TNBC subgroups analyzing the miRNA expression profile, and to identify new prognostic and predictive biomarkers. We conducted a human miRNome analysis by TaqMan Low Density Array comparing different TNBC subtypes, defined by immunohistochemical basal markers EGFR and CK5/6. RT-qPCR confirmed differential expression of microRNAs. To inspect the function of the selected targets we perform Gene Ontology and KEGG enrichment analysis. We identified a single miRNA signature given by miR-135b expression level, which was strictly related to TNBC with basal-like phenotype. miR-135b target analysis revealed a role in the TGF-beta, WNT and ERBB pathways. A significant positive correlation was identified between neoplastic proliferative index and miR-135b expression. These findings confirm the oncogenic roles of miR-135b in the pathogenesis of TNBC expressing basal markers. A potential negative prognostic role of miR-135b overexpression might be related to the positive correlation with high proliferative index. Our study implies potential clinical applications: miR-135b could be a potential therapeutic target in basal-like TNBCs.
Uva, Paolo; Cossu-Rocca, Paolo; Loi, Federica; Pira, Giovanna; Murgia, Luciano; Orrù, Sandra; Floris, Matteo; Muroni, Maria Rosaria; Sanges, Francesca; Carru, Ciriaco; Angius, Andrea; De Miglio, Maria Rosaria
2018-01-01
The clinical and genetic heterogeneity of Triple Negative Breast Cancer (TNBC) and the lack of unambiguous molecular targets contribute to the inadequacy of current therapeutic options for these variants. MicroRNAs (miRNA) are a class of small highly conserved regulatory endogenous non-coding RNA, which can alter the expression of genes encoding proteins and may play a role in the dysregulation of cellular pathways. Our goal was to improve the knowledge of the molecular pathogenesis of TNBC subgroups analyzing the miRNA expression profile, and to identify new prognostic and predictive biomarkers. We conducted a human miRNome analysis by TaqMan Low Density Array comparing different TNBC subtypes, defined by immunohistochemical basal markers EGFR and CK5/6. RT-qPCR confirmed differential expression of microRNAs. To inspect the function of the selected targets we perform Gene Ontology and KEGG enrichment analysis. We identified a single miRNA signature given by miR-135b expression level, which was strictly related to TNBC with basal-like phenotype. miR-135b target analysis revealed a role in the TGF-beta, WNT and ERBB pathways. A significant positive correlation was identified between neoplastic proliferative index and miR-135b expression. These findings confirm the oncogenic roles of miR-135b in the pathogenesis of TNBC expressing basal markers. A potential negative prognostic role of miR-135b overexpression might be related to the positive correlation with high proliferative index. Our study implies potential clinical applications: miR-135b could be a potential therapeutic target in basal-like TNBCs. PMID:29725243
Immunocytochemistry of the olfactory marker protein.
Monti-Graziadei, G A; Margolis, F L; Harding, J W; Graziadei, P P
1977-12-01
The olfactory marker protein has been localized, by means of immunohistochemical techniques in the primary olfactory neurons of mice. The olfactory marker protein is not present in the staminal cells of the olfactory neuroepithelium, and the protein may be regarded as indicative of the functional stage of the neurons. Our data indicate that the olfactory marker protein is present in the synaptic terminals of the olfactory neurons at the level of the olfactory bulb glomeruli. The postsynaptic profiles of both mitral and periglomerular cells are negative.
Strzeżek, R; Szemplińska, K; Filipowicz, K; Kordan, W
2015-01-01
The aim of this study was to evaluate the influence of season on selected qualitative semen characteristics and biochemical markers of canine seminal plasma. Whole ejaculates were collected from 5 crossbred dogs aged 2-8 years. The study covered a period of one year divided into four seasons: spring (March, April, May), summer (June, July, August), autumn (September, October, November) and winter (December, January, February). Semen samples were subjected to macroscopic and microscopic analyses to determine semen volume, total sperm counts and sperm morphology parameters. The study also involved the determination of sperm motility parameters (CASA system), sperm plasma membrane integrity (SPMI, fluorescent staining SYBR-14/PI), sperm mitochondrial membrane potential (MMP, fluorescent staining JC-1/PI) and the ATP content of sperm cells. Total protein content (TPC) and the activity of alkaline phosphatase (AP) and acid phosphatase (AcP) were determined in biochemical analyses of seminal plasma. No significant differences in ejaculate volume, SMPI or ATP content of sperm cells were observed between seasons. The highest total sperm counts were reported in ejaculates acquired in summer and autumn. The lowest MMP values were determined in summer ejaculates. No significant differences in sperm motility (MOT) were observed throughout the experiment, but ejaculates collected in autumn and winter were characterized by the highest progressive motility (PMOT). AP activity and TPC were not significantly affected by season. However, AcP activity levels were significantly lower in autumn than in the remaining seasons. Seasonal variations in the analyzed macroscopic and microscopic parameters of ejaculates and biochemical markers of seminal plasma did not exert a clear negative effect on the quality of canine semen.
Kumar, Amanika; Torres, Michelle L; Cliby, William A; Kalli, Kimberly R; Bogani, Giorgio; Aletti, Giovanni; Nitschmann, Caroline C; Multinu, Francesco; Weaver, Amy L; Block, Matthew S; Mariani, Andrea
2017-07-01
To identify preoperative nutritional and inflammatory markers that predict perioperative outcomes in patients with ovarian cancer (OC). Fifty patients who underwent primary debulking for advanced (stage III/IV) OC were selected from a cohort of patients who underwent surgery between 2002 and 2009. We analyzed C-reactive protein (CRP), interleukin-6 (IL6) and albumin and their impact on mortality and surgical outcomes. Two patients were excluded since they did not have adequate measurements of CRP and IL6. Among the remaining patients, 25 (52%) were ≥70 years old. Nine (19%), 12 (25%) and 12 (25%) patients had low serum albumin (<3.0 g/dl), elevated CRP (≥70 mg/l) and elevated IL6 (≥24 pg/ml), respectively. Age was a significant predictor of non-home discharge (p=0.01). Low serum albumin (<3.0 g/dl) was a predictor of death within 6 month (p=0.03). Elevated CRP (≥70 mg/l) was a predictor of non-home discharge (p=0.02), death within 6 months (p=0.02), death within 12 months (p=0.04), and longer hospital stay (p=0.01). Elevated IL6 (≥24 pg/ml) was a predictor of non-home discharge (p=0.002) and surgical complications (p=0.02), and also associated with longer hospital stay (p=0.03). Poor nutrition and high inflammatory status negatively influence surgical and oncological outcomes of patients with OC. These preoperative markers can be used for selection of patients for neoadjuvant chemotherapy at high risk of short survival, non-home discharge and long hospital stay. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Niemiec, Joanna; Adamczyk, Agnieszka; Małecki, Krzysztof; Ambicka, Aleksandra; Ryś, Janusz
2013-04-01
It is still being discussed if the assessment of basal markers or if adhesion molecules expression contributes additional prognostic information to the classic prognostic factors and hence should be included into standard morphologic reports. The aim of the study was to assess the prognostic significance of: (i) classification recommended by St Gallen experts (ii) tumor grade, expression of (iii) basal markers, (iv) adhesion molecules, and (v) matrix metalloproteinase 2 (MMP-2) in patients with T1-T2 N0M0 chemotherapy-naive ductal breast cancer. In 79 patients with tumors characterized by estrogen receptor (ER) and progesterone receptor (PgR) positive, human epidermal growth factor receptor 2 negative (HER2) phenotype and MIB-1 labeling index (MIB-l) LI ≤ 15% (low-risk group) cumulative 17-year breast cancer-specific survival probability was 100% and was significantly higher than in 95 patients from the high-risk group (ER(-)/PgR(-)/HER2(-) or HER2(+) or MIB-1 LI > 15%) (72.5%). We found that MMP-2 fibroblast expression indicated 2 subgroups with significantly different survival rates in women with grade 3 tumor (88.9% for MMP-2 positivity and 56.0% for negativity). Cox multivariate analysis revealed that both grade 3 combined with stromal fibroblast MMP-2(-) and a high-risk group according to St Gallen recommendations are independent negative prognostic factors that influence survival of patients with breast cancer. To the best of our knowledge, we have shown for the first time that MMP-2(-) in stromal fibroblasts might indicate poor survivors in the group of patients with grade 3 tumors and that the cumulative effect of both above-mentioned parameters might be helpful in selecting the high-risk individuals from the group of patients with luminal B subtype/HER2(+)/triple negative phenotype identified according to St Gallen recommendations. Copyright © 2013 Elsevier Inc. All rights reserved.
Hassan, Masroor; Abdullah, Hafez Mohammad Ammar; Wahid, Abdul; Qamar, Muhammad Ashraf
2018-06-08
Terminal deoxynucleotidyl transferase (TdT)-negative T-cell lymphoblastic lymphoma is a variant of T-cell lymphoblastic lymphoma/T-cell lymphoblastic leukaemia. TdT is a marker of immaturity expressed in 90%-95% cases of lymphoblastic lymphoma and useful in differentiating it from other mature lymphomas/leukaemias. It has been associated with poorer response to chemotherapy and a more aggressive outcome. Here we present a case of TdT-negative T-cell lymphoblastic lymphoma in a 28-year-old man who presented with superior vena cava syndrome. The patient was treated with hyper-cyclophosphamide,vincristine, Adriamycin, dexamethasone (CVAD), however unfortunately suffered a relapse 1 year later. A unique feature of our case was that on relapse, the patient lost expression of the T-cell lineage-specific marker CD3, which has previously not been reported in association with TdT-negative T-cell lymphoblastic lymphoma. The patient failed to respond to chemotherapy on his relapse and died. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Salivary immunoglobulin-A as a marker of stress during strenuous physical training.
Carins, Julia; Booth, Christine
2002-12-01
Immunoglobulin-A in saliva (SIgA) has been proven to be decreased during periods of stress, a change that also correlates with increased disease risk. Concentration of SIgA is negatively associated with dietary deprivation, negative moods, and anxiety. SIgA was evaluated as a marker of the severity of stress during a 19-day Royal Australian Air Force (RAAF) survival course, during which students experienced hunger, thirst, boredom, loneliness, and extreme heat and cold combined with demanding physical effort. There were 27 men and 2 women who participated. Students kept daily food diaries, from which daily intakes of energy and macronutrients were calculated. Saliva samples were collected on 9 d for the measurement of the ratio of SIgA to albumin (Alb). Students completed a health checklist and the State Anxiety Inventory on the same 9 d and the Profile of Mood States on 3 of the days. Dietary restriction, consumption of alcohol, body mass loss, occurrence of upper respiratory tract infection, and negative emotions were negatively associated with SIgA:Alb. SIgA:Alb is a useful marker of the severity of stresses encountered during stressful training.
Antibody-immobilized column for quick cell separation based on cell rolling.
Mahara, Atsushi; Yamaoka, Tetsuji
2010-01-01
Cell separation using methodological standards that ensure high purity is a very important step in cell transplantation for regenerative medicine and for stem cell research. A separation protocol using magnetic beads has been widely used for cell separation to isolate negative and positive cells. However, not only the surface marker pattern, e.g., negative or positive, but also the density of a cell depends on its developmental stage and differentiation ability. Rapid and label-free separation procedures based on surface marker density are the focus of our interest. In this study, we have successfully developed an antiCD34 antibody-immobilized cell-rolling column, that can separate cells depending on the CD34 density of the cell surfaces. Various conditions for the cell-rolling column were optimized including graft copolymerization, and adjustment of the column tilt angle, and medium flow rate. Using CD34-positive and -negative cell lines, the cell separation potential of the column was established. We observed a difference in the rolling velocities between CD34-positive and CD34-negative cells on antibody-immobilized microfluidic device. Cell separation was achieved by tilting the surface 20 degrees and the increasing medium flow. Surface marker characteristics of the isolated cells in each fraction were analyzed using a cell-sorting system, and it was found that populations containing high density of CD34 were eluted in the delayed fractions. These results demonstrate that cells with a given surface marker density can be continuously separated using the cell rolling column.
Sentential Negative Markers as Pro-Forms of Negative Sentences in Modern Mongolian
ERIC Educational Resources Information Center
Dagvasumberel, Enkhjargal
2015-01-01
Negation in modern Mongolian was analyzed by scholars namely: Luvsanvandan Sh (1968, 2000), Wonsoo Yu (1991), Mönkh-Amgalan Yu (1998), Purev-Ochir B. (1998, 2001), Byambasan P. (2006), Kunihiko Hasimoto (2008), BatIreedui J.(2009), Ravdan E. (2009), Mönkh-Amgalan Yu & Kan Shin (2014). Sentential negation in modern Mongolian is not sufficiently…
REJC, BARBARA; KATO, YOJI; KARAS-KUZELICKI, NATASA; OSREDKAR, JOSKO; GERSAK, KSENIJA
2016-01-01
Pregnancy is a physiological state accompanied by excessive levels of oxidative stress (OS), due to the increased demand and utilisation of oxygen. There is increasing evidence that maternally augmented OS exerts an adverse effect on pregnancy outcome. The aim of the present prospective study was to determine the association between the urinary concentration of relatively novel OS markers measured in the second trimester of pregnancy and the infant characteristics at birth. The maternal levels of urinary hexanoyl-lysine (HEL), propanoyl-lysine (PRL), dityrosine (DiY) and 3-nitrotyrosine (NY) were evaluated in generally healthy pregnant subjects to determine their association with birth weight, gestation at delivery and Apgar score. The observed levels of the markers were in agreement with those measured in healthy non-pregnant subjects in a previous study. A positive correlation was detected between HEL and PRL, as well as between HEL and DiY. Although the absence of a correlation between NY and the other markers has been previously noted in a non-pregnant population, a positive correlation in the pair PRL-NY (r=0.367; P<0.001) was observed in the present study. Maternal cigarette smoking was associated with increased urinary PRL levels (P=0.034). The most notable observation in the present study was that high levels of PRL and NY were associated with low Apgar scores at 1 and 5 min after birth (OR, 1.098 and 2.084 for PRL and NY, respectively; P<0.05). However, poor predictive accuracy was shown. For NY, the following results were obtained: Area under the curve (AUC), 0.818; sensitivity, 100%; specificity, 57%; positive predictive value (PPV), 11.54%; and negative predictive value (NPV), 100%. For PLR the values were as follows: AUC, 0.802; sensitivity, 100%; specificity, 62.6%; PPV, 13.05%; and NPV, 100%. DiY was negatively associated with preterm birth risk (OR=0.703; P=0.028). In conclusion, the results of the present study indicated the presence of OS in the second trimester of pregnancy, which was detected with damage to lipids and proteins and associated with an adverse Apgar score; however, the selected urinary markers exhibited poor positive predictive efficacy. PMID:26997995
Rejc, Barbara; Kato, Yoji; Karas-Kuzelicki, Natasa; Osredkar, Josko; Gersak, Ksenija
2016-03-01
Pregnancy is a physiological state accompanied by excessive levels of oxidative stress (OS), due to the increased demand and utilisation of oxygen. There is increasing evidence that maternally augmented OS exerts an adverse effect on pregnancy outcome. The aim of the present prospective study was to determine the association between the urinary concentration of relatively novel OS markers measured in the second trimester of pregnancy and the infant characteristics at birth. The maternal levels of urinary hexanoyl-lysine (HEL), propanoyl-lysine (PRL), dityrosine (DiY) and 3-nitrotyrosine (NY) were evaluated in generally healthy pregnant subjects to determine their association with birth weight, gestation at delivery and Apgar score. The observed levels of the markers were in agreement with those measured in healthy non-pregnant subjects in a previous study. A positive correlation was detected between HEL and PRL, as well as between HEL and DiY. Although the absence of a correlation between NY and the other markers has been previously noted in a non-pregnant population, a positive correlation in the pair PRL-NY (r=0.367; P<0.001) was observed in the present study. Maternal cigarette smoking was associated with increased urinary PRL levels (P=0.034). The most notable observation in the present study was that high levels of PRL and NY were associated with low Apgar scores at 1 and 5 min after birth (OR, 1.098 and 2.084 for PRL and NY, respectively; P<0.05). However, poor predictive accuracy was shown. For NY, the following results were obtained: Area under the curve (AUC), 0.818; sensitivity, 100%; specificity, 57%; positive predictive value (PPV), 11.54%; and negative predictive value (NPV), 100%. For PLR the values were as follows: AUC, 0.802; sensitivity, 100%; specificity, 62.6%; PPV, 13.05%; and NPV, 100%. DiY was negatively associated with preterm birth risk (OR=0.703; P=0.028). In conclusion, the results of the present study indicated the presence of OS in the second trimester of pregnancy, which was detected with damage to lipids and proteins and associated with an adverse Apgar score; however, the selected urinary markers exhibited poor positive predictive efficacy.
Diamantis, N; Xynos, I D; Amptulah, S; Karadima, M; Skopelitis, H; Tsavaris, N
2013-01-01
To investigate the prognostic significance of smoking in addition to established risk factors in patients with Dukes stage B and C colorectal cancer (CRC). 291 consecutive non-selected CRC patients were studied retrospectively. Twenty-three variables were examined using a regression statistical model to identify relevant prognostic factors related to disease free survival (DFS) and overall survival (OS). On multivariate analysis DFS was found to be negatively affected in patients with a smoking history of ≤10 pack-years vs. non-smokers (p<0.016). Additionally, performance status (PS)<90 (p<0.001), Dukes stage C (p<0.001) and elevated tumor markers (p<0.001) at the time of diagnosis were found to adversely affect DFS. Smoking also had a significant association with relapse. Patients with a smoking history of ≤10 pack-years had 2.45 (p<0.018) higher risk of recurrence compared to patients with no smoking history. OS was influenced by Karnofsky performance status (PS), Dukes stage, and elevated tumor markers. In particular patients with PS< 90 had a 4.69-fold higher risk of death (p<0.001) than patients with better PS. Stage C disease was associated with 2.27-fold higher risk of death (p<0.001) than stage B disease, and patients with elevated tumor markers at the time of diagnosis had 2.74-fold higher risk of death (p<0.014) when compared to those whose tumor markers were normal at presentation. Our study associates smoking and relapse incidence in non-clinical- trial CRC patients and reiterates the prognostic significance of PS, stage and tumor markers at the time of diagnosis.
Chen, Wei; Xie, Minkai; Yang, Bin; Bharadwaj, Shantaram; Song, Lujie; Liu, Guihua; Yi, Shanhong; Ye, Gang; Atala, Anthony; Zhang, Yuanyuan
2017-02-01
Stem cells are regarded as possible cell therapy candidates for skeletal muscle regeneration. However, invasive harvesting of those cells can cause potential harvest-site morbidity. The goal of this study was to assess whether human urine-derived stem cells (USCs), obtained through non-invasive procedures, can differentiate into skeletal muscle linage cells (Sk-MCs) and potentially be used for skeletal muscle regeneration. In this study, USCs were harvested from six healthy individuals aged 25-55. Expression profiles of cell-surface markers were assessed by flow cytometry. To optimize the myogenic differentiation medium, we selected two from four different types of myogenic differentiation media to induce the USCs. Differentiated USCs were identified with myogenic markers by gene and protein expression. USCs were implanted into the tibialis anterior muscles of nude mice for 1 month. The results showed that USCs displayed surface markers with positive staining for CD24, CD29, CD44, CD73, CD90, CD105, CD117, CD133, CD146, SSEA-4 and STRO-1, and negative staining for CD14, CD31, CD34 and CD45. After myogenic differentiation, a change in morphology was observed from 'rice-grain'-like cells to spindle-shaped cells. The USCs expressed specific Sk-MC transcripts and protein markers (myf5, myoD, myosin, and desmin) after being induced with different myogenic culture media. Implanted cells expressed Sk-MC markers stably in vivo. Our findings suggest that USCs are able to differentiate into the Sk-MC lineage in vitro and after being implanted in vivo. Thus, they might be a potential source for cell injection therapy in the use of skeletal muscle regeneration. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.
Olfactory Bulb Deep Short-Axon Cells Mediate Widespread Inhibition of Tufted Cell Apical Dendrites.
Burton, Shawn D; LaRocca, Greg; Liu, Annie; Cheetham, Claire E J; Urban, Nathaniel N
2017-02-01
In the main olfactory bulb (MOB), the first station of sensory processing in the olfactory system, GABAergic interneuron signaling shapes principal neuron activity to regulate olfaction. However, a lack of known selective markers for MOB interneurons has strongly impeded cell-type-selective investigation of interneuron function. Here, we identify the first selective marker of glomerular layer-projecting deep short-axon cells (GL-dSACs) and investigate systematically the structure, abundance, intrinsic physiology, feedforward sensory input, neuromodulation, synaptic output, and functional role of GL-dSACs in the mouse MOB circuit. GL-dSACs are located in the internal plexiform layer, where they integrate centrifugal cholinergic input with highly convergent feedforward sensory input. GL-dSAC axons arborize extensively across the glomerular layer to provide highly divergent yet selective output onto interneurons and principal tufted cells. GL-dSACs are thus capable of shifting the balance of principal tufted versus mitral cell activity across large expanses of the MOB in response to diverse sensory and top-down neuromodulatory input. The identification of cell-type-selective molecular markers has fostered tremendous insight into how distinct interneurons shape sensory processing and behavior. In the main olfactory bulb (MOB), inhibitory circuits regulate the activity of principal cells precisely to drive olfactory-guided behavior. However, selective markers for MOB interneurons remain largely unknown, limiting mechanistic understanding of olfaction. Here, we identify the first selective marker of a novel population of deep short-axon cell interneurons with superficial axonal projections to the sensory input layer of the MOB. Using this marker, together with immunohistochemistry, acute slice electrophysiology, and optogenetic circuit mapping, we reveal that this novel interneuron population integrates centrifugal cholinergic input with broadly tuned feedforward sensory input to modulate principal cell activity selectively. Copyright © 2017 the authors 0270-6474/17/371117-22$15.00/0.
Li, Xianggan; Volrath, Sandy L.; Nicholl, David B.G.; Chilcott, Charles E.; Johnson, Marie A.; Ward, Eric R.; Law, Marcus D.
2003-01-01
In this article, we report the isolation of plant protoporphyrinogen oxidase (PPO) genes and the isolation of herbicide-tolerant mutants. Subsequently, an Arabidopsis double mutant (Y426M + S305L) was used to develop a selectable marker system for Agrobacterium tumefaciens-mediated transformation of maize (Zea mays) and to obtain multiple events tolerant to the PPO family of herbicides. Maize transformants were produced via butafenacil selection using a flexible light regime to increase selection pressure. Butafenacil selection per se did not change transgene copy number distribution relative to other selectable marker systems, but the most tolerant events identified in the greenhouse were more likely to contain multiple copies of the introduced mutant PPO gene. To date, more than 2,500 independent transgenic maize events have been produced using butafenacil selection. The high frequency of A. tumefaciens-mediated transformation via PPO selection enabled us to obtain single-copy transgenic maize lines tolerant to field levels of butafenacil. PMID:12972658
Metabolite and transcript markers for the prediction of potato drought tolerance.
Sprenger, Heike; Erban, Alexander; Seddig, Sylvia; Rudack, Katharina; Thalhammer, Anja; Le, Mai Q; Walther, Dirk; Zuther, Ellen; Köhl, Karin I; Kopka, Joachim; Hincha, Dirk K
2018-04-01
Potato (Solanum tuberosum L.) is one of the most important food crops worldwide. Current potato varieties are highly susceptible to drought stress. In view of global climate change, selection of cultivars with improved drought tolerance and high yield potential is of paramount importance. Drought tolerance breeding of potato is currently based on direct selection according to yield and phenotypic traits and requires multiple trials under drought conditions. Marker-assisted selection (MAS) is cheaper, faster and reduces classification errors caused by noncontrolled environmental effects. We analysed 31 potato cultivars grown under optimal and reduced water supply in six independent field trials. Drought tolerance was determined as tuber starch yield. Leaf samples from young plants were screened for preselected transcript and nontargeted metabolite abundance using qRT-PCR and GC-MS profiling, respectively. Transcript marker candidates were selected from a published RNA-Seq data set. A Random Forest machine learning approach extracted metabolite and transcript markers for drought tolerance prediction with low error rates of 6% and 9%, respectively. Moreover, by combining transcript and metabolite markers, the prediction error was reduced to 4.3%. Feature selection from Random Forest models allowed model minimization, yielding a minimal combination of only 20 metabolite and transcript markers that were successfully tested for their reproducibility in 16 independent agronomic field trials. We demonstrate that a minimum combination of transcript and metabolite markers sampled at early cultivation stages predicts potato yield stability under drought largely independent of seasonal and regional agronomic conditions. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Jo, Ick Hyun; Kim, Young Chang; Kim, Dong Hwi; Kim, Kee Hong; Hyun, Tae Kyung; Ryu, Hojin; Bang, Kyong Hwan
2017-10-01
The development of molecular markers is one of the most useful methods for molecular breeding and marker-based molecular associated selections. Even though there is less information on the reference genome, molecular markers are indispensable tools for determination of genetic variation and identification of species with high levels of accuracy and reproducibility. The demand for molecular approaches for marker-based breeding and genetic discriminations in Panax species has greatly increased in recent times and has been successfully applied for various purposes. However, owing to the existence of diverse molecular techniques and differences in their principles and applications, there should be careful consideration while selecting appropriate marker types. In this review, we outline the recent status of different molecular marker applications in ginseng research and industrial fields. In addition, we discuss the basic principles, requirements, and advantages and disadvantages of the most widely used molecular markers, including restriction fragment length polymorphism, random amplified polymorphic DNA, sequence tag sites, simple sequence repeats, and single nucleotide polymorphisms.
Combining markers with and without the limit of detection
Dong, Ting; Liu, Catherine Chunling; Petricoin, Emanuel F.; Tang, Liansheng Larry
2014-01-01
In this paper, we consider the combination of markers with and without the limit of detection (LOD). LOD is often encountered when measuring proteomic markers. Because of the limited detecting ability of an equipment or instrument, it is difficult to measure markers at a relatively low level. Suppose that after some monotonic transformation, the marker values approximately follow multivariate normal distributions. We propose to estimate distribution parameters while taking the LOD into account, and then combine markers using the results from the linear discriminant analysis. Our simulation results show that the ROC curve parameter estimates generated from the proposed method are much closer to the truth than simply using the linear discriminant analysis to combine markers without considering the LOD. In addition, we propose a procedure to select and combine a subset of markers when many candidate markers are available. The procedure based on the correlation among markers is different from a common understanding that a subset of the most accurate markers should be selected for the combination. The simulation studies show that the accuracy of a combined marker can be largely impacted by the correlation of marker measurements. Our methods are applied to a protein pathway dataset to combine proteomic biomarkers to distinguish cancer patients from non-cancer patients. PMID:24132938
Surrogate biochemical markers: precise measurement for strategic drug and biologics development.
Lee, J W; Hulse, J D; Colburn, W A
1995-05-01
More efficient drug and biologics development is necessary for future success of pharmaceutical and biotechnology companies. One way to achieve this objective is to use rationally selected surrogate markers to improve the early decision-making process. Using typical clinical chemistry methods to measure biochemical markers may not ensure adequate precision and reproducibility. In contrast, using analytical methods that meet good laboratory practices along with rational selection and validation of biochemical markers can give those who use them a competitive advantage over those who do not by providing meaningful data for earlier decision making.
2013-01-01
Background Brachiaria ruziziensis is one of the most important forage species planted in the tropics. The application of genomic tools to aid the selection of superior genotypes can provide support to B. ruziziensis breeding programs. However, there is a complete lack of information about the B. ruziziensis genome. Also, the availability of genomic tools, such as molecular markers, to support B. ruziziensis breeding programs is rather limited. Recently, next-generation sequencing technologies have been applied to generate sequence data for the identification of microsatellite regions and primer design. In this study, we present a first validated set of SSR markers for Brachiaria ruziziensis, selected from a de novo partial genome assembly of single-end Illumina reads. Results A total of 85,567 perfect microsatellite loci were detected in contigs with a minimum 10X coverage. We selected a set of 500 microsatellite loci identified in contigs with minimum 100X coverage for primer design and synthesis, and tested a subset of 269 primer pairs, 198 of which were polymorphic on 11 representative B. ruziziensis accessions. Descriptive statistics for these primer pairs are presented, as well as estimates of marker transferability to other relevant brachiaria species. Finally, a set of 11 multiplex panels containing the 30 most informative markers was validated and proposed for B. ruziziensis genetic analysis. Conclusions We show that the detection and development of microsatellite markers from genome assembled Illumina single-end DNA sequences is highly efficient. The developed markers are readily suitable for genetic analysis and marker assisted selection of Brachiaria ruziziensis. The use of this approach for microsatellite marker development is promising for species with limited genomic information, whose breeding programs would benefit from the use of genomic tools. To our knowledge, this is the first set of microsatellite markers developed for this important species. PMID:23324172
Dominant selectable markers for Penicillium spp. transformation and gene function studies
USDA-ARS?s Scientific Manuscript database
Penicillium spp. has been genetically manipulated and gene function studies have utilized single gene deletion strains for phenotypic analysis. Fungal transformation experiments have relied on hygromycin and hygromycin phosphotransferase (hph) as the main dominant selectable marker (DSM) system in P...
Forages and Pastures Symposium: development of and field experience with drought-tolerant maize.
Soderlund, S; Owens, F N; Fagan, C
2014-07-01
Drought-tolerant maize hybrids currently are being marketed by several seed suppliers. Such hybrids were developed by phenotypic and marker-assisted selection or through genetic modification and tested by exposing these hybrids to various degrees of water restriction. As drought intensifies, crop yields and survival progressively decline. Water need differs among plants due to differences in root structure, evaporative loss, capacity to store water or enter temporary dormancy, and plant genetics. Availability of water differs widely not only with rainfall and irrigation but also with numerous soil and agronomic factors (e.g., soil type, slope, seeding rates, tillage practices). Reduced weed competition, enhanced pollen shed and silk production, and deep, robust root growth help to reduce the negative impacts of drought. Selected drought-tolerant maize hybrids have consistently yielded more grain even when drought conditions are not apparent either due to reduced use of soil water reserves before water restriction or due to greater tolerance of intermittent water shortages. In DuPont Pioneer trials, whole plant NDF digestibility of maize increased with water restriction, perhaps due to an increased leaf to stem ratio. Efficiency of water use, measured as dry matter or potential milk yield from silage per unit of available water, responded quadratically to water restriction, first increasing slightly but then decreasing as water restriction increased. For grain production, water restriction has its greatest negative impact during or after silking through reducing the number of kernels and reducing kernel filling. For silage production, water restriction during the vegetative growth stage negatively impacts plant height and biomass yield. Earlier planting and shorter season maize hybrids help to avoid midsummer heat stress during pollination and can reduce the number of irrigation events needed. Although drought tolerance of maize hybrids has been improved due to genetic selection or biotech approaches, selecting locally adapted hybrids or crops, adjusting seeding rates, and modifying tillage and irrigation practices are important factors that can improve efficiency of use of available water by grain and forage crops.
Marsden, Clare D; Woodroffe, Rosie; Mills, Michael G L; McNutt, J Weldon; Creel, Scott; Groom, Rosemary; Emmanuel, Masenga; Cleaveland, Sarah; Kat, Pieter; Rasmussen, Gregory S A; Ginsberg, Joshua; Lines, Robin; André, Jean-Marc; Begg, Colleen; Wayne, Robert K; Mable, Barbara K
2012-03-01
Deciphering patterns of genetic variation within a species is essential for understanding population structure, local adaptation and differences in diversity between populations. Whilst neutrally evolving genetic markers can be used to elucidate demographic processes and genetic structure, they are not subject to selection and therefore are not informative about patterns of adaptive variation. As such, assessments of pertinent adaptive loci, such as the immunity genes of the major histocompatibility complex (MHC), are increasingly being incorporated into genetic studies. In this study, we combined neutral (microsatellite, mtDNA) and adaptive (MHC class II DLA-DRB1 locus) markers to elucidate the factors influencing patterns of genetic variation in the African wild dog (Lycaon pictus); an endangered canid that has suffered extensive declines in distribution and abundance. Our genetic analyses found all extant wild dog populations to be relatively small (N(e) < 30). Furthermore, through coalescent modelling, we detected a genetic signature of a recent and substantial demographic decline, which correlates with human expansion, but contrasts with findings in some other African mammals. We found strong structuring of wild dog populations, indicating the negative influence of extensive habitat fragmentation and loss of gene flow between habitat patches. Across populations, we found that the spatial and temporal structure of microsatellite diversity and MHC diversity were correlated and strongly influenced by demographic stability and population size, indicating the effects of genetic drift in these small populations. Despite this correlation, we detected signatures of selection at the MHC, implying that selection has not been completely overwhelmed by genetic drift. © 2012 Blackwell Publishing Ltd.
2013-01-01
Background Machine learning techniques are becoming useful as an alternative approach to conventional medical diagnosis or prognosis as they are good for handling noisy and incomplete data, and significant results can be attained despite a small sample size. Traditionally, clinicians make prognostic decisions based on clinicopathologic markers. However, it is not easy for the most skilful clinician to come out with an accurate prognosis by using these markers alone. Thus, there is a need to use genomic markers to improve the accuracy of prognosis. The main aim of this research is to apply a hybrid of feature selection and machine learning methods in oral cancer prognosis based on the parameters of the correlation of clinicopathologic and genomic markers. Results In the first stage of this research, five feature selection methods have been proposed and experimented on the oral cancer prognosis dataset. In the second stage, the model with the features selected from each feature selection methods are tested on the proposed classifiers. Four types of classifiers are chosen; these are namely, ANFIS, artificial neural network, support vector machine and logistic regression. A k-fold cross-validation is implemented on all types of classifiers due to the small sample size. The hybrid model of ReliefF-GA-ANFIS with 3-input features of drink, invasion and p63 achieved the best accuracy (accuracy = 93.81%; AUC = 0.90) for the oral cancer prognosis. Conclusions The results revealed that the prognosis is superior with the presence of both clinicopathologic and genomic markers. The selected features can be investigated further to validate the potential of becoming as significant prognostic signature in the oral cancer studies. PMID:23725313
Mawas, Amany Sayed; Amatya, Vishwa Jeet; Kushitani, Kei; Kai, Yuichiro; Miyata, Yoshihiro; Okada, Morihito; Takeshima, Yukio
2018-01-09
The differential diagnosis of epithelioid mesothelioma from lung adenocarcinoma and squamous cell carcinoma requires the positive and negative immunohistochemical markers of mesothelioma. The IMIG guideline has suggested the use of Calretinin, D2-40, WT1, and CK5/6 as mesothelial markers, TTF-1, Napsin-A, Claudin 4, CEA as lung adenocarcinoma markers p40, p63, CK5/6, MOC-31 as squamous cell markers. However, use of other immunohistochemical markers is still necessary. We evaluated 65 epithelioid mesotheliomas, 60 adenocarcinomas, and 57 squamous cell carcinomas of the lung for MUC4 expression by immunohistochemistry and compared with the previously known immunohistochemical markers. MUC4 expression was not found in any of 65 cases of epithelioid mesothelioma. In contrast, MUC4 expression was observed in 50/60(83.3%) cases of lung adenocarcinoma and 50/56(89.3%) cases of lung squamous cell carcinoma. The negative MUC4 expression showed 100% sensitivity, 86.2% specificity and accuracy rate of 91.2% to differentiate epithelioid mesothelioma from lung carcinoma. The sensitivity, specificity, and accuracy of MUC4 are comparable to that of previously known markers of lung adenocarcinoma and squamous cell carcinoma, namely CEA, Claudin 4 and better than that of MOC-31. In conclusion, MUC4 immunohistochemistry is useful for differentiation of epithelioid mesothelioma from lung carcinoma, either adenocarcinoma or squamous cell carcinoma.
Biswal, Jitendra K; Subramaniam, Saravanan; Ranjan, Rajeev; Sharma, Gaurav K; Misri, Jyoti; Pattnaik, Bramhadev
2015-11-01
Foot-and-mouth disease (FMD) is a highly contagious, economically important disease of transboundary importance. Regular vaccination with chemically inactivated FMD vaccine is the major means of controlling the disease in endemic countries like India. However, the traditional inactivated vaccines may sometimes contain traces of FMD viral (FMDV) non-structural protein (NSP), therefore, interfering with the NSP-based serological discrimination between infected and vaccinated animals. The availability of marker vaccine for differentiating FMD infected from vaccinated animals (DIVA) would be crucial for the control and subsequent eradication of FMD in India. In this study, we constructed a negative marker FMDV serotype O virus (vaccine strain O IND R2/1975), containing dual deletions of amino acid residues 93-143 and 10-37 in the non-structural proteins 3A and 3B, respectively through reverse genetics approach. The negative marker virus exhibited similar growth kinetics and plaque morphology in cell culture as compared to the wild type virus. In addition, we also developed and evaluated an indirect ELISA (I-ELISA) targeted to the deleted 3AB NSP region (truncated 3AB) which could be used as a companion differential diagnostic assay. The diagnostic sensitivity and specificity of the truncated 3AB I-ELISA were found to be 95.5% and 96%, respectively. The results from this study suggest that the availability negative marker virus and companion diagnostic assay could open a promising new avenue for the application of DIVA compatible marker vaccine for the control of FMD in India. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.
Verma, Nishant; Beretvas, S Natasha; Pascual, Belen; Masdeu, Joseph C; Markey, Mia K
2018-03-14
Combining optimized cognitive (Alzheimer's Disease Assessment Scale- Cognitive subscale, ADAS-Cog) and atrophy markers of Alzheimer's disease for tracking progression in clinical trials may provide greater sensitivity than currently used methods, which have yielded negative results in multiple recent trials. Furthermore, it is critical to clarify the relationship among the subcomponents yielded by cognitive and imaging testing, to address the symptomatic and anatomical variability of Alzheimer's disease. Using latent variable analysis, we thoroughly investigated the relationship between cognitive impairment, as assessed on the ADAS-Cog, and cerebral atrophy. A biomarker was developed for Alzheimer's clinical trials that combines cognitive and atrophy markers. Atrophy within specific brain regions was found to be closely related with impairment in cognitive domains of memory, language, and praxis. The proposed biomarker showed significantly better sensitivity in tracking progression of cognitive impairment than the ADAS-Cog in simulated trials and a real world problem. The biomarker also improved the selection of MCI patients (78.8±4.9% specificity at 80% sensitivity) that will evolve to Alzheimer's disease for clinical trials. The proposed biomarker provides a boost to the efficacy of clinical trials focused in the mild cognitive impairment (MCI) stage by significantly improving the sensitivity to detect treatment effects and improving the selection of MCI patients that will evolve to Alzheimer's disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Iriemenam, Nnaemeka C.; Pandey, Janardan P.; Williamson, John; Blackstock, Anna J.; Yesupriya, Ajay; Namboodiri, Aryan M.; Rocca, Keith M.; van Eijk, Anna Maria; Ayisi, John; Oteino, Juliana; Lal, Renu B.; ter Kuile, Feiko O.; Steketee, Richard; Nahlen, Bernard; Slutsker, Laurence; Shi, Ya Ping
2013-01-01
Immunoglobulin (Ig) GM and KM allotypes, genetic markers of γ and κ chains, are associated with humoral immune responsiveness. Previous studies have shown the relationships between GM6-carrying haplotypes and susceptibility to malaria infection in children and adults; however, the role of the genetic markers in placental malaria (PM) infection and PM with HIV co-infection during pregnancy has not been investigated. We examined the relationship between the gene polymorphisms of Ig GM6 and KM allotypes and the risk of PM infection in pregnant women with known HIV status. DNA samples from 728 pregnant women were genotyped for GM6 and KM alleles using polymerase chain reaction-restriction fragment length polymorphism method. Individual GM6 and KM genotypes and the combined GM6 and KM genotypes were assessed in relation to PM in HIV-1 negative and positive women, respectively. There was no significant effect of individual GM6 and KM genotypes on the risk of PM infection in HIV-1 negative and positive women. However, the combination of homozygosity for GM6(+) and KM3 was associated with decreased risk of PM (adjusted OR, 0.25; 95% CI, 0.08–0.8; P = 0.019) in HIV-1 negative women while in HIV-1 positive women the combination of GM6(+/−) with either KM1-3 or KM1 was associated with increased risk of PM infection (adjusted OR, 2.10; 95% CI, 1.18–3.73; P = 0.011). Hardy-Weinberg Equilibrium (HWE) tests further showed an overall significant positive F(is) (indication of deficit in heterozygotes) for GM6 while there was no deviation for KM genotype frequency from HWE in the same population. These findings suggest that the combination of homozygous GM6(+) and KM3 may protect against PM in HIV-1 negative women while the HIV-1 positive women with heterozygous GM6(+/−) combined with KM1-3 or KM1 may be more susceptible to PM infection. The deficit in heterozygotes for GM6 further suggests that GM6 could be under selection likely by malaria infection. PMID:23326546
Zhao, M; Chen, M; Tan, A S C; Cheah, F S H; Mathew, J; Wong, P C; Chong, S S
2017-07-01
Essentials Preimplantation genetic diagnosis (PGD) of severe hemophilia A relies on linkage analysis. Simultaneous multi-marker screening can simplify selection of informative markers in a couple. We developed a single-tube tetradecaplex panel of polymorphic markers for hemophilia A PGD use. Informative markers can be used for linkage analysis alone or combined with mutation detection. Background It is currently not possible to perform single-cell preimplantation genetic diagnosis (PGD) to directly detect the common inversion mutations of the factor VIII (F8) gene responsible for severe hemophilia A (HEMA). As such, PGD for such inversion carriers relies on indirect analysis of linked polymorphic markers. Objectives To simplify linkage-based PGD of HEMA, we aimed to develop a panel of highly polymorphic microsatellite markers located near the F8 gene that could be simultaneously genotyped in a multiplex-PCR reaction. Methods We assessed the polymorphism of various microsatellite markers located ≤ 1 Mb from F8 in 177 female subjects. Highly polymorphic markers were selected for co-amplification with the AMELX/Y indel dimorphism in a single-tube reaction. Results Thirteen microsatellite markers located within 0.6 Mb of F8 were successfully co-amplified with AMELX/Y in a single-tube reaction. Observed heterozygosities of component markers ranged from 0.43 to 0.84, and ∼70-80% of individuals were heterozygous for ≥ 5 markers. The tetradecaplex panel successfully identified fully informative markers in a couple interested in PGD for HEMA because of an intragenic F8 point mutation, with haplotype phasing established through a carrier daughter. In-vitro fertilization (IVF)-PGD involved single-tube co-amplification of fully informative markers with AMELX/Y and the mutation-containing F8 amplicon, followed by microsatellite analysis and amplicon mutation-site minisequencing analysis. Conclusions The single-tube multiplex-PCR format of this highly polymorphic microsatellite marker panel simplifies identification and selection of informative markers for linkage-based PGD of HEMA. Informative markers can also be easily co-amplified with mutation-containing F8 amplicons for combined mutation detection and linkage analysis. © 2017 International Society on Thrombosis and Haemostasis.
Bilhou-Nabéra, Chrystèle; Bidet, Audrey; Eclache, Virginie; Lippert, Eric; Mozziconacci, Marie-Joëlle
2016-10-01
The recent years have witnessed tremendous progress in the molecular characterization of Philadelphia-negative myeloproliferative neoplasms (MPN). Beside a better understanding of pathophysiology, these abnormalities often constitute very useful diagnostic markers in diseases where exclusion of reactive states used to be the strongest argument. However, conventional and molecular cytogenetics keep a major interest in MPN, either as a second line exploration, in cases where no molecular marker is available, for differential diagnosis or as a proof of clonality or in first line for cases with hyperleukocytosis, for differential diagnosis (CML), to evidence druggable targets (ABL1, RET, PDGFR…) or as a prognosis marker. In this article, we will review the interest of cytogenetic techniques in myeloproliferative neoplasms.
Avian Disease and Oncology Laboratory (ADOL) research update
USDA-ARS?s Scientific Manuscript database
GENOMICS To meet the growing demands of consumers, the poultry industry will need to continue to improve methods of selection in breeding programs for production and associated traits. One possible solution is genome-wide marker-assisted selection (GWMAS). In brief, evenly-spaced genetic markers s...
Molecular breeding for the development of multiple disease resistance in Basmati rice.
Singh, Atul; Singh, Vikas K; Singh, S P; Pandian, R T P; Ellur, Ranjith K; Singh, Devinder; Bhowmick, Prolay K; Gopala Krishnan, S; Nagarajan, M; Vinod, K K; Singh, U D; Prabhu, K V; Sharma, T R; Mohapatra, T; Singh, A K
2012-01-01
Basmati rice grown in the Indian subcontinent is highly valued for its unique culinary qualities. Production is, however, often constrained by diseases such as bacterial blight (BB), blast and sheath blight (ShB). The present study developed Basmati rice with inbuilt resistance to BB, blast and ShB using molecular marker-assisted selection. The rice cultivar 'Improved Pusa Basmati 1' (carrying the BB resistance genes xa13 and Xa21) was used as the recurrent parent and cultivar 'Tetep' (carrying the blast resistance gene Pi54 and ShB resistance quality trait loci (QTL), qSBR11-1) was the donor. Marker-assisted foreground selection was employed to identify plants possessing resistance alleles in the segregating generations along with stringent phenotypic selection for faster recovery of the recurrent parent genome (RPG) and phenome (RPP). Background analysis with molecular markers was used to estimate the recovery of RPG in improved lines. Foreground selection coupled with stringent phenotypic selection identified plants homozygous for xa13, Xa21 and Pi54, which were advanced to BC(2)F(5) through pedigree selection. Marker-assisted selection for qSBR11-1 in BC(2)F(5) using flanking markers identified seven homozygous families. Background analysis revealed that RPG recovery was up to 89.5%. Screening with highly virulent isolates of BB, blast and ShB showed that the improved lines were resistant to all three diseases and were on a par with 'Improved Pusa Basmati 1' for yield, duration and Basmati grain quality. This is the first report of marker-assisted transfer of genes conferring resistance to three different diseases in rice wherein genes xa13 and Xa21 for BB resistance, Pi54 for blast resistance, and a major QTL qSBR11-1 have been combined through marker-assisted backcross breeding. In addition to offering the potential for release as cultivars, the pyramided lines will serve as useful donors of gene(s) for BB, blast and ShB in future Basmati rice breeding programmes.
Petersen, William; Umbeck, Paul; Hokanson, Karen; Halsey, Mark
2005-01-01
Cassava is an important subsistence crop grown only in the tropics, and represents a major source of calories for many people in developing countries. Improvements in the areas of resistance to insects and viral diseases, enhanced nutritional qualities, reduced cyanogenic content and modified starch characteristics are urgently needed. Traditional breeding is hampered by the nature of the crop, which has a high degree of heterozygosity, irregular flowering, and poor seed set. Biotechnology has the potential to enhance crop improvement efforts, and genetic engineering techniques for cassava have thus been developed over the past decade. Selectable and scorable markers are critical to efficient transformation technology, and must be evaluated for biosafety, as well as efficiency and cost-effectiveness. In order to facilitate research planning and regulatory submission, the literature on biosafety aspects of the selectable and scorable markers currently used in cassava biotechnology is surveyed. The source, mode of action and current use of each marker gene is described. The potential for toxicity, allergenicity, pleiotropic effects, horizontal gene transfer, and the impact of these on food or feed safety and environmental safety is evaluated. Based on extensive information, the selectable marker genes nptII, hpt, bar/pat, and manA, and the scorable marker gene uidA, all have little risk in terms of biosafety. These appear to represent the safest options for use in cassava biotechnology available at this time.
Development of disease-resistant marker-free tomato by R/RS site-specific recombination.
Khan, Raham Sher; Nakamura, Ikuo; Mii, Masahiro
2011-06-01
The selection marker genes, imparting antibiotic or herbicide resistance, in the final transgenics have been criticized by the public and considered a hindrance in their commercialization. Multi-auto-transformation (MAT) vector system has been one of the strategies to produce marker-free transgenic plants without using selective chemicals and plant growth regulators (PGRs). In the study reported here, isopentenyltransferase (ipt) gene was used as a selection marker and wasabi defensin (WD) gene, isolated from Wasabia japonica as a target gene. WD was cloned from the binary vector, pEKH-WD to an ipt-type MAT vector, pMAT21 by gateway cloning and transferred to Agrobacterium tumefaciens strain EHA105. Infected cotyledons of tomato cv. Reiyo were cultured on PGR- and antibiotic-free MS medium. Adventitious shoots were developed by the explants infected with the pMAT21/wasabi defensin. The same PGR- and antibiotic-free MS medium was used in subcultures of the adventitious shoot lines (ASLs) to produce ipt and normal shoots. Approximately, 6 months after infection morphologically normal shoots were produced. Molecular analyses of the developed shoots confirmed the integration of gene of interest (WD) and excision of the selection marker (ipt). Expression of WD was confirmed by Northern blot and Western blot analyses. The marker-free transgenic plants exhibited enhanced resistance against Botrytis cinerea (gray mold), Alternaria solani (early blight), Fusarium oxysporum (Fusarium wilt) and Erysiphe lycopersici (powdery mildew).
Specialized sperm function tests in varicocele and the future of andrology laboratory.
Majzoub, Ahmad; Esteves, Sandro C; Gosálvez, Jaime; Agarwal, Ashok
2016-01-01
Varicocele is a common medical condition entangled with many controversies. Though it is highly prevalent in men with infertility, still it marks its presence in males who do have normal fertility. Determining which patients are negatively affected by varicocele would enable clinicians to better select those men who benefitted the most from surgery. Since conventional semen analysis has been limited in its ability to evaluate the negative effects of varicocele on fertility, a multitude of specialized laboratory tests have emerged. In this review, we examine the role and significance of specialized sperm function tests with regards to varicocele. Among the various tests, analysis of sperm DNA fragmentation and measurements of oxidative stress markers provide an independent measure of fertility in men with varicocele. These diagnostic modalities have both diagnostic and prognostic information complementary to, but distinct from conventional sperm parameters. Test results can guide management and aid in monitoring intervention outcomes. Proteomics, metabolomics, and genomics are areas; though still developing, holding promise to revolutionize our understanding of reproductive physiology, including varicocele.
Huberman, Eliezer [Chicago, IL; Baccam, Mekhine J [Woodridge, IL
2007-02-27
The present invention relates to a nucleic acid sequence and its corresponding protein sequence useful as a dominant selectable marker in eukaryotes. More specifically the invention relates to a nucleic acid encoding a bacterial IMPDH gene that has been engineered into a eukaryotic expression vectors, thereby permitting bacterial IMPDH expression in mammalian cells. Bacterial IMPDH expression confers resistance to MPA which can be used as dominant selectable marker in eukaryotes including mammals. The invention also relates to expression vectors and cells that express the bacterial IMPDH gene as well as gene therapies and protein synthesis.
Assessment of bone metabolism in premenopausal females with hyperthyroidism and hypothyroidism.
Tuchendler, Dominika; Bolanowski, Marek
2013-01-01
Osteoporosis is one of the commonest metabolic diseases of bone. Its possible causes may include thyroid hormonal dysfunction. The objective of this study was to evaluate the effects of hyperthyroidism and hypothyroidism on osseous tissue metabolism in premenopausal women. 38 women with hyperthyroidism, 40 with hypothyroidism and 41 healthy women participated in this study. Initially after 6 and 12 months, each patient underwent selected hormonal, immunological and biochemical tests, measurement of concentrations of bone turnover markers and densitometry were also performed. On initial evaluation, lower cortical bone density was found in patients with hyperthyroidism (femoral neck). After 12 months, an increase in BMD was seen, but it was still lower than in the control group. Statistically significantly higher concentrations of bone turnover markers, decreasing from the sixth month of treatment, were noted only in the group with hyperthyroidism. Statistically significant differences were not noted in the femoral neck nor in the lumbar spine BMD in patients with hypothyroidism. Hyperthyroidism poses a negative effect on bone metabolism. Hypothyroidism in premenopausal females does not have any influence on bone density.
Possible evolutionary origins of human female sexual fluidity.
Kanazawa, Satoshi
2017-08-01
I propose an evolutionary theory of human female sexual fluidity and argue that women may have been evolutionarily designed to be sexually fluid in order to allow them to have sex with their cowives in polygynous marriage and thus reduce conflict and tension inherent in such marriage. In addition to providing an extensive definition and operationalization of the concept of sexual fluidity and specifying its ultimate function for women, the proposed theory can potentially solve several theoretical and empirical puzzles in evolutionary psychology and sex research. Analyses of the National Longitudinal Study of Adolescent Health (Add Health) confirm the theory's predictions that: (i) women (but not men) who experience increased levels of sexual fluidity have a larger number of children (suggesting that female sexual fluidity, if heritable, may be evolutionarily selected); (ii) women (but not men) who experience marriage or parenthood early in adult life subsequently experience increased levels of sexual fluidity; and (iii) sexual fluidity is significantly positively correlated with known markers of unrestricted sexual orientation among women whereas it is significantly negatively correlated with such markers among men. © 2016 Cambridge Philosophical Society.
Selective antitumor activity of roscovitine in head and neck cancer
Biktasova, Asel; Bellinger, Gary; Yarbrough, Wendell G.; Issaeva, Natalia
2016-01-01
Radiation and chemotherapy that are commonly used to treat human cancers damage cellular DNA. DNA damage appears to be more toxic to cancer cells than normal cells, most likely due to deregulated checkpoint activation and/or deficiency in DNA repair pathways that are characteristics of many tumors. However, unwanted side effects arise as a result of DNA damage to normal cells during the treatment. Here, we show that roscovitine, a cyclin-dependent kinase (CDK) inhibitor that inhibits CDK-1, CDK-2, CDK-5, CDK-7, and CDK-9 due to competitive binding to the ATP site on the kinases, causes significant DNA damage followed by p53-dependent cell death in human papilloma virus (HPV)-positive, but not in HPV-negative, head and neck cancer cells. Since HPV positivity was a molecular marker for increased sensitivity of cells to roscovitine, we reasoned that systemic roscovitine administration would not be toxic to healthy HPV-negative tissue. Indeed, low roscovitine doses significantly inhibited the growth of HPV-associated xenografted tumors in mice without causing any detectable side effects. Given that inhibition of CDKs has been shown to inhibit replication of several viruses, we suggest that roscovitine treatment may represent a selective and safe targeted therapeutic option against HPV-positive head and neck cancer. PMID:27233076
Fu, Yong-Bi; Yang, Mo-Hua; Zeng, Fangqin; Biligetu, Bill
2017-01-01
Molecular plant breeding with the aid of molecular markers has played an important role in modern plant breeding over the last two decades. Many marker-based predictions for quantitative traits have been made to enhance parental selection, but the trait prediction accuracy remains generally low, even with the aid of dense, genome-wide SNP markers. To search for more accurate trait-specific prediction with informative SNP markers, we conducted a literature review on the prediction issues in molecular plant breeding and on the applicability of an RNA-Seq technique for developing function-associated specific trait (FAST) SNP markers. To understand whether and how FAST SNP markers could enhance trait prediction, we also performed a theoretical reasoning on the effectiveness of these markers in a trait-specific prediction, and verified the reasoning through computer simulation. To the end, the search yielded an alternative to regular genomic selection with FAST SNP markers that could be explored to achieve more accurate trait-specific prediction. Continuous search for better alternatives is encouraged to enhance marker-based predictions for an individual quantitative trait in molecular plant breeding. PMID:28729875
Niu, Yuze; Gao, Fengtao; Zhao, Yongwei; Zhang, Jing; Sun, Jian; Shao, Changwei; Liao, Xiaolin; Wang, Lei; Tian, Yongsheng; Chen, Songlin
2012-01-01
High-density genetic linkage maps were constructed for the Japanese flounder (Paralichthys olivaceus). A total of 1624 microsatellite markers were polymorphic in the reference family. Linkage analysis using JoinMap 4.0 resulted in the mapping of 1487 markers to 24 linkage groups, a result which was consistent with the 24 chromosomes seen in chromosome spreads. The female map was composed of 1257 markers, covering a total of 1663.8 cM with an average interval 1.35 cM between markers. The male map consisted of 1224 markers, spanning 1726.5 cM, with an average interval of 1.44 cM. The genome length in the Japanese flounder was estimated to be 1730.3 cM for the females and 1798.0 cM for the males, a coverage of 96.2% for the female and 96.0% for the male map. The mean recombination at common intervals throughout the genome revealed a slight difference between sexes, i.e. 1.07 times higher in the male than female. High-density genetic linkage maps are very useful for marker-assisted selection (MAS) programs for economically valuable traits in this species and for further evolutionary studies in flatfish and vertebrate species. Furthermore, four quantiative trait loci (QTL) associated with growth traits were mapped on the genetic map. One QTL was identified for body weight on LG 14 f, which explained 14.85% of the total variation of the body weight. Three QTL were identified for body width on LG14f and LG14m, accounting for 16.75%, 13.62% and 13.65% of the total variation in body width, respectively. The additive effects were evident as negative values. There were four QTL for growth traits clustered on LG14, which should prove to be very useful for improving growth traits using molecular MAS. PMID:23209734
Effectiveness of Vascular Markers (Immunohistochemical Stains) in Soft Tissue Sarcomas.
Naeem, Namra; Mushtaq, Sajid; Akhter, Noreen; Hussain, Mudassar; Hassan, Usman
2018-05-01
To ascertain the effectiveness of IHC markers of vascular origin like CD31, CD34, FLI1 and ERG in vascular soft tissue sarcomas including angiosarcomas, Kaposi sarcomas, epithelioid hemangioendothelioma and a non-vascular soft tissue sarcoma (Epithelioid sarcoma). Descriptive study. Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, from 2011 to 2017. Diagnosed cases of angiosarcomas (n=48), epithelioid hemangioendothelioma (n=9), Kaposi sarcoma (n=9) and epithelioid sarcoma (n=20) were selected. Immunohistochemical staining as performed on formalin fixed paraffin embedded sections. The sections were stained for the following markers: CD34 (VENTANA clone Q Bend 10), CD31 (Leica clone 1 A 10), FLI1 (CELL MARQUE clone MRQ-1) and ERG (CELL MARQUE clone EP111). A complete panel of CD34, CD31 and ERG was applied on 8/48 cases of angiosarcomas with triple positivity in 6 cases. Eight cases showed positivity for only CD31 and ERG and 2 cases showed positivity for only ERG. A complete panel of CD34, CD31 and ERG was applied on 3/9 cases of epithelioid hemangioendothelioma with positivity for all markers in 2 cases. Combined positivity for ERG and CD34 was seen in 2 cases and on 4 cases only CD31 immunohistochemical was solely applied with 100% positivity. FLI1 was not applied on any case. Among 9 cases of Kaposi sarcoma, ERG, CD34 and CD31 in combination were applied on only 1 case with triple positivity. Remaining cases show positivity for either CD34, CD31 or FLI1. Majority of cases of epithelioid sarcomas were diagnosed on the basis of cytokeratin and CD34 positivity with loss of INI1. The other vascular markers showed negativity in all cases. Among these four markers, ERG immunohistochemical stain is highly effective for endothelial differentiation due to its specific nuclear staining pattern in normal blood vessel endothelial cells (internal control) as well as neoplastic cells of vascular tumors and lack of background staining.
Chester, Annalise L; Edwards, Andrew M; Crowe, Melissa; Quirk, Frances
2013-07-01
Military environmental survival training (EST) is designed and considered to evoke significant stressors to military personnel in preparation for combat-like scenarios. The aim of this study was to observe and report selected physiological, biochemical, psychological, and performance responses to this intense 15-day program of Royal Australian Air Force (RAAF) EST. Fourteen RAAF participants undertook the EST course. Physiological and psychological responses were collected across the 15 days across outcomes: (1) biochemical markers (blood lactate, interlukin-6, and creatine kinase), (2) performance and anthropometric indices (vertical jump, body mass), and (3) psychological questionnaires profile of mood states, depression anxiety stress scale, Kessler-10 etc.). Creatine kinase concentration increased significantly from baseline to day 5 (p < 0.05) and thereafter remained elevated for the remaining 10 days of EST (128%; p < 0.01). Vertical jump (-10%; p < 0.01) and body mass (-8%; p < 0.01) both decreased across 15 days of EST, while there were no significant change in interlukin-6. Negative psychological responses were observed for mood (p < 0.01), depression (p < 0.05), anxiety (p < 0.01), and stress (p < 0.01) following the EST course. This case study showed the RAAF EST course imposed significant physiological and psychological stress as observed from markers of muscle damage, deterioration in physical performance, substantial weight loss, negative mood, and psychological distress. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.
[Predisposition to alcohol and drug consumption in schizophrenia-vulnerable people].
Fumero, A; Santamaría, C; Navarrete, G
A large amount of current schizophrenia research has been centered on the understanding of its etiological mechanisms and the detection of vulnerability markers in people at risk. This vulnerability called schizotypy can be identified in people not affected by the illness at the clinical level. To check if the schizotypic personality disorder as a vulnerability marker of the disorders in the schizophrenic spectrum predicts the presence of psychopathologic symptoms and alcohol and drugs intake. From a population of 442 university students tested with the Schizotypy Personality Questionnaire (SPQ), it was selected a sample including people scoring on the 20% superior and inferior for the characteristic factors of schizophrenia corresponding to positive symptoms (cognitive-perceptual), negative symptoms (interpersonal) and thought disorder (disorganized). Furthermore, it was evaluated the presence of psychopathological problems and symptoms. Also, the participants gave information about alcohol and drugs intake as a passive coping strategy with stress. Compared with the low scored, subjects with high scores in the schizotypic personality disorder showed a significant increase in the presence of psychopathological problems and symptoms and a higher alcohol and drugs intake. That occurs mainly when those scores are found in symptoms associated to thought disorder and negative symptoms as lack of interest in social activities and emotional flattening. The schizotypic personality disorder, in accordance with its role as vulnerability factor, seems to co-occur with a higher volume of somatic and psychopathologic symptoms, and alcohol and drugs intake.
Yang, Huaan; Tao, Ye; Zheng, Zequn; Shao, Di; Li, Zhenzhong; Sweetingham, Mark W; Buirchell, Bevan J; Li, Chengdao
2013-02-01
Selection for phomopsis stem blight disease (PSB) resistance is one of the key objectives in lupin (Lupinus angustifolius L.) breeding programs. A cross was made between cultivar Tanjil (resistant to PSB) and Unicrop (susceptible). The progeny was advanced into F(8) recombinant inbred lines (RILs). The RIL population was phenotyped for PSB disease resistance. Twenty plants from the RIL population representing disease resistance and susceptibility was subjected to next-generation sequencing (NGS)-based restriction site-associated DNA sequencing on the NGS platform Solexa HiSeq2000, which generated 7,241 single nucleotide polymorphisms (SNPs). Thirty-three SNP markers showed the correlation between the marker genotypes and the PSB disease phenotype on the 20 representative plants, which were considered as candidate markers linked to a putative R gene for PSB resistance. Seven candidate markers were converted into sequence-specific PCR markers, which were designated as PhtjM1, PhtjM2, PhtjM3, PhtjM4, PhtjM5, PhtjM6 and PhtjM7. Linkage analysis of the disease phenotyping data and marker genotyping data on a F(8) population containing 187 RILs confirmed that all the seven converted markers were associated with the putative R gene within the genetic distance of 2.1 CentiMorgan (cM). One of the PCR markers, PhtjM3, co-segregated with the R gene. The seven established PCR markers were tested in the 26 historical and current commercial cultivars released in Australia. The numbers of "false positives" (showing the resistance marker allele band but lack of the putative R gene) for each of the seven PCR markers ranged from nil to eight. Markers PhtjM4 and PhtjM7 are recommended in marker-assisted selection for PSB resistance in the Australian national lupin breeding program due to its wide applicability on breeding germplasm and close linkage to the putative R gene. The results demonstrated that application of NGS technology is a rapid and cost-effective approach in development of markers for molecular plant breeding.
Nudin, Nur Fatihah Hasan; Ali, Abdul Manaf; Ngah, Norhayati; Mazlan, Nor Zuhailah; Mat, Nashriyah; Ghani, Mohd Noor Abd; Alias, Nadiawati; Zakaria, Abd Jamil; Jahan, Md Sarwar
2017-08-01
Plant breeding is a way of selection of a particular individual for the production of the progeny by separating or combining desired characteristics. The objective of this study was to justify different characteristics of Dioscorea hispida (Ubi gadong) varieties using molecular techniques to select the best variety for sustainable production at the farmer's level. A total of 160 germplasms of Ubi gadong were collected from different locations at the Terengganu and Kelantan states of Malaysia. Forty eight (48) out of 160 germplasms were selected as "primary" selection based on yield and other qualitative characters. Selected collections were then grown and maintained for ISSR marker-assisted genetic diversity analysis. Overall plant growth and yield of tubers were also determined. A total of 12 ISSR markers were tested to justify the characteristics of Ubi gadong varieties among which three markers showed polymorphic bands and on average 57.3% polymorphism were observed representing the highest variation among germplasms. The ISSR marker based on UPGMA cluster analysis grouped all 48 D. hispida into 10 vital groups that proved a vast genetic variation among germplasm collections. Therefore, hybridization should be made between two distant populations. The D. hispida is already proved as the highest starch content tuber crops and very rich in vitamins with both micro and macro minerals. Considering all these criteria and results from marker-assisted diversity analysis, accessions that are far apart based on their genetic coefficient (like DH27 and DH71; DH30 and DH70; DH43 and DH62; DH45 and DH61; DH77 and DH61; DH78 and DH57) could be selected as parents for further breeding programs. This will bring about greater diversity, which will lead to high productive index in terms of increase in yield and overall quality and for the ultimate target of sustainable Ubi gadong production. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.
The Power to Detect Linkage Disequilibrium with Quantitative Traits in Selected Samples
Abecasis, Gonçalo R.; Cookson, William O. C.; Cardon, Lon R.
2001-01-01
Results from power studies for linkage detection have led to many ongoing and planned collections of phenotypically extreme nuclear families. Given the great expense of collecting these families and the imminent availability of a dense diallelic marker map, the families are likely to be used in allelic-association as well as linkage studies. However, optimal selection strategies for linkage may not be equally powerful for association. We examine the power to detect linkage disequilibrium for quantitative traits after phenotypic selection. The results encompass six selection strategies that are in widespread use, including single selection (two designs), affected sib pairs, concordant and discordant pairs, and the extreme-concordant and -discordant design. Selection of sibships on the basis of one extreme proband with high or low trait scores provides as much power as discordant sib pairs but requires the screening and phenotyping of substantially fewer initial families from which to select. Analysis of the role of allele frequencies within each selection design indicates that common trait alleles generally offer the most power, but similarities between the marker- and trait-allele frequencies are much more important than the trait-locus frequency alone. Some of the most widespread selection designs, such as single selection, yield power gains only when both the marker and quantitative trait loci (QTL) are relatively rare in the population. In contrast, discordant pairs and the extreme-proband design provide power for the broadest range of QTL–marker-allele frequency differences. Overall, proband selection from either tail provides the best balance of power, robustness, and simplicity of ascertainment for family-based association analysis. PMID:11349228
NASA Astrophysics Data System (ADS)
Mazurek, Przemysław
2013-09-01
Matchmoving (Match Moving) is the process used for the estimation of camera movements for further integration of acquired video image with computer graphics. The estimation of movements is possible using pattern recognition, 2D and 3D tracking algorithms. The main problem for the workflow is the partial occlusion of markers by the actor, because manual rotoscoping is necessary for fixing of the chroma-keyed footage. In the paper, the partial occlusion problem is solved using the invented, selectively active electronic markers. The sensor network with multiple infrared links detects occlusion state (no-occlusion, partial, full) and switch LED's based markers.
Asea, Godfrey; Vivek, Bindiganavile S; Bigirwa, George; Lipps, Patrick E; Pratt, Richard C
2009-05-01
Maize production in sub-Saharan Africa incurs serious losses to epiphytotics of foliar diseases. Quantitative trait loci conditioning partial resistance (rQTL) to infection by causal agents of gray leaf spot (GLS), northern corn leaf blight (NCLB), and maize streak have been reported. Our objectives were to identify simple-sequence repeat (SSR) molecular markers linked to consensus rQTL and one recently identified rQTL associated with GLS, and to determine their suitability as tools for selection of improved host resistance. We conducted evaluations of disease severity phenotypes in separate field nurseries, each containing 410 F2:3 families derived from a cross between maize inbred CML202 (NCLB and maize streak resistant) and VP31 (a GLS-resistant breeding line) that possess complimentary rQTL. F2:3 families were selected for resistance based on genotypic (SSR marker), phenotypic, or combined data and the selected F3:4 families were reevaluated. Phenotypic values associated with SSR markers for consensus rQTL in bins 4.08 for GLS, 5.04 for NCLB, and 1.04 for maize streak significantly reduced disease severity in both generations based on single-factor analysis of variance and marker-interval analysis. These results were consistent with the presence of homozygous resistant parent alleles, except in bin 8.06, where markers were contributed by the NCLB-susceptible parent. Only one marker associated with resistance could be confirmed in bins 2.09 (GLS) and 3.06 (NCLB), illustrating the need for more robust rQTL discovery, fine-mapping, and validation prior to undertaking marker-based selection.
The Development of Quality Control Genotyping Approaches: A Case Study Using Elite Maize Lines.
Chen, Jiafa; Zavala, Cristian; Ortega, Noemi; Petroli, Cesar; Franco, Jorge; Burgueño, Juan; Costich, Denise E; Hearne, Sarah J
2016-01-01
Quality control (QC) of germplasm identity and purity is a critical component of breeding and conservation activities. SNP genotyping technologies and increased availability of markers provide the opportunity to employ genotyping as a low-cost and robust component of this QC. In the public sector available low-cost SNP QC genotyping methods have been developed from a very limited panel of markers of 1,000 to 1,500 markers without broad selection of the most informative SNPs. Selection of optimal SNPs and definition of appropriate germplasm sampling in addition to platform section impact on logistical and resource-use considerations for breeding and conservation applications when mainstreaming QC. In order to address these issues, we evaluated the selection and use of SNPs for QC applications from large DArTSeq data sets generated from CIMMYT maize inbred lines (CMLs). Two QC genotyping strategies were developed, the first is a "rapid QC", employing a small number of SNPs to identify potential mislabeling of seed packages or plots, the second is a "broad QC", employing a larger number of SNP, used to identify each germplasm entry and to measure heterogeneity. The optimal marker selection strategies combined the selection of markers with high minor allele frequency, sampling of clustered SNP in proportion to marker cluster distance and selecting markers that maintain a uniform genomic distribution. The rapid and broad QC SNP panels selected using this approach were further validated using blind test assessments of related re-generation samples. The influence of sampling within each line was evaluated. Sampling 192 individuals would result in close to 100% possibility of detecting a 5% contamination in the entry, and approximately a 98% probability to detect a 2% contamination of the line. These results provide a framework for the establishment of QC genotyping. A comparison of financial and time costs for use of these approaches across different platforms is discussed providing a framework for institutions involved in maize conservation and breeding to assess the resource use effectiveness of QC genotyping. Application of these research findings, in combination with existing QC approaches, will ensure the regeneration, distribution and use in breeding of true to type inbred germplasm. These findings also provide an effective approach to optimize SNP selection for QC genotyping in other species.
Precision-engineering the Pseudomonas aeruginosa genome with two-step allelic exchange
Hmelo, Laura R.; Borlee, Bradley R.; Almblad, Henrik; Love, Michelle E.; Randall, Trevor E.; Tseng, Boo Shan; Lin, Chuyang; Irie, Yasuhiko; Storek, Kelly M.; Yang, Jaeun Jane; Siehnel, Richard J.; Howell, P. Lynne; Singh, Pradeep K.; Tolker-Nielsen, Tim; Parsek, Matthew R.; Schweizer, Herbert P.; Harrison, Joe J.
2016-01-01
Allelic exchange is an efficient method of bacterial genome engineering. This protocol describes the use of this technique to make gene knockouts and knockins, as well as single nucleotide insertions, deletions and substitutions in Pseudomonas aeruginosa. Unlike other approaches to allelic exchange, this protocol does not require heterologous recombinases to insert or excise selective markers from the target chromosome. Rather, positive and negative selection are enabled solely by suicide vector-encoded functions and host cell proteins. Here, mutant alleles, which are flanked by regions of homology to the recipient chromosome, are synthesized in vitro and then cloned into allelic exchange vectors using standard procedures. These suicide vectors are then introduced into recipient cells by conjugation. Homologous recombination then results in antibiotic resistant single-crossover mutants in which the plasmid has integrated site-specifically into the chromosome. Subsequently, unmarked double-crossover mutants are isolated directly using sucrose-mediated counter-selection. This two-step process yields seamless mutations that are precise to a single base pair of DNA. The entire procedure requires ~2 weeks. PMID:26492139
Molecular markers of neuropsychological functioning and Alzheimer's disease.
Edwards, Melissa; Balldin, Valerie Hobson; Hall, James; O'Bryant, Sid
2015-03-01
The current project sought to examine molecular markers of neuropsychological functioning among elders with and without Alzheimer's disease (AD) and determine the predictive ability of combined molecular markers and select neuropsychological tests in detecting disease presence. Data were analyzed from 300 participants (n = 150, AD and n = 150, controls) enrolled in the Texas Alzheimer's Research and Care Consortium. Linear regression models were created to examine the link between the top five molecular markers from our AD blood profile and neuropsychological test scores. Logistical regressions were used to predict AD presence using serum biomarkers in combination with select neuropsychological measures. Using the neuropsychological test with the least amount of variance overlap with the molecular markers, the combined neuropsychological test and molecular markers was highly accurate in detecting AD presence. This work provides the foundation for the generation of a point-of-care device that can be used to screen for AD.
Preoperative Molecular Markers in Thyroid Nodules.
Sahli, Zeyad T; Smith, Philip W; Umbricht, Christopher B; Zeiger, Martha A
2018-01-01
The need for distinguishing benign from malignant thyroid nodules has led to the pursuit of differentiating molecular markers. The most common molecular tests in clinical use are Afirma ® Gene Expression Classifier (GEC) and Thyroseq ® V2. Despite the rapidly developing field of molecular markers, several limitations exist. These challenges include the recent introduction of the histopathological diagnosis "Non-Invasive Follicular Thyroid neoplasm with Papillary-like nuclear features", the correlation of genetic mutations within both benign and malignant pathologic diagnoses, the lack of follow-up of molecular marker negative nodules, and the cost-effectiveness of molecular markers. In this manuscript, we review the current published literature surrounding the diagnostic value of Afirma ® GEC and Thyroseq ® V2. Among Afirma ® GEC studies, sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) ranged from 75 to 100%, 5 to 53%, 13 to 100%, and 20 to 100%, respectively. Among Thyroseq ® V2 studies, Se, Sp, PPV, and NPV ranged from 40 to 100%, 56 to 93%, 13 to 90%, and 48 to 97%, respectively. We also discuss current challenges to Afirma ® GEC and Thyroseq ® V2 utility and clinical application, and preview the future directions of these rapidly developing technologies.
Abbas, Ghulam; Hameed, Amjad; Rizwan, Muhammad; Ahsan, Muhammad; Asghar, Muhammad J; Iqbal, Nayyer
2015-01-01
Molecular confirmation of interspecific recombinants is essential to overcome the issues like self-pollination, environmental influence, and inadequacy of morphological characteristics during interspecific hybridization. The present study was conducted for genetic confirmation of mungbean (female) and mashbean (male) interspecific crosses using molecular markers. Initially, polymorphic random amplified polymorphic DNA (RAPD), universal rice primers (URP), and simple sequence repeats (SSR) markers differentiating parent genotypes were identified. Recombination in hybrids was confirmed using these polymorphic DNA markers. The NM 2006 × Mash 88 was most successful interspecific cross. Most of true recombinants confirmed by molecular markers were from this cross combination. SSR markers were efficient in detecting genetic variability and recombination with reference to specific chromosomes and particular loci. SSR (RIS) and RAPD identified variability dispersed throughout the genome. In conclusion, DNA based marker assisted selection (MAS) efficiently confirmed the interspecific recombinants. The results provided evidence that MAS can enhance the authenticity of selection in mungbean improvement program.
Targeted Proteomics Approach for Precision Plant Breeding.
Chawade, Aakash; Alexandersson, Erik; Bengtsson, Therese; Andreasson, Erik; Levander, Fredrik
2016-02-05
Selected reaction monitoring (SRM) is a targeted mass spectrometry technique that enables precise quantitation of hundreds of peptides in a single run. This technique provides new opportunities for multiplexed protein biomarker measurements. For precision plant breeding, DNA-based markers have been used extensively, but the potential of protein biomarkers has not been exploited. In this work, we developed an SRM marker panel with assays for 104 potato (Solanum tuberosum) peptides selected using univariate and multivariate statistics. Thereafter, using random forest classification, the prediction markers were identified for Phytopthora infestans resistance in leaves, P. infestans resistance in tubers, and plant yield in potato leaf secretome samples. The results suggest that the marker panel has the predictive potential for three traits, two of which have no commercial DNA markers so far. Furthermore, the marker panel was also tested and found to be applicable to potato clones not used during the marker development. The proposed workflow is thus a proof-of-concept for targeted proteomics as an efficient readout in accelerated breeding for complex and agronomically important traits.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doyen, J.; Trastour, C.; Ettore, F.
2014-08-15
Highlights: • Glycolytic markers are highly expressed in triple negative breast cancers. • Lactate/H{sup +} symporter MCT4 demonstrated the strongest deleterious impact on survival. • MCT4 should serve as a new prognostic factor in node-negative breast cancers. - Abstract: Background: {sup 18}Fluor-deoxy-glucose PET-scanning of glycolytic metabolism is being used for staging in many tumors however its impact on prognosis has never been studied in breast cancer. Methods: Glycolytic and hypoxic markers: glucose transporter (GLUT1), carbonic anhydrase IX (CAIX), monocarboxylate transporter 1 and 4 (MCT1, 4), MCT accessory protein basigin and lactate-dehydrogenase A (LDH-A) were assessed by immunohistochemistry in two cohortsmore » of breast cancer comprising 643 node-negative and 127 triple negative breast cancers (TNBC) respectively. Results: In the 643 node-negative breast tumor cohort with a median follow-up of 124 months, TNBC were the most glycolytic (≈70%), followed by Her-2 (≈50%) and RH-positive cancers (≈30%). Tumoral MCT4 staining (without stromal staining) was a strong independent prognostic factor for metastasis-free survival (HR = 0.47, P = 0.02) and overall-survival (HR = 0.38, P = 0.002). These results were confirmed in the independent cohort of 127 cancer patients. Conclusion: Glycolytic markers are expressed in all breast tumors with highest expression occurring in TNBC. MCT4, the hypoxia-inducible lactate/H{sup +} symporter demonstrated the strongest deleterious impact on survival. We propose that MCT4 serves as a new prognostic factor in node-negative breast cancer and can perhaps act soon as a theranostic factor considering the current pharmacological development of MCT4 inhibitors.« less
Pool, Lindsay R; Needham, Belinda L; Burgard, Sarah A; Elliott, Michael R; de Leon, Carlos F Mendes
2017-08-01
Experiencing a negative wealth shock in late middle age may cause high levels of stress and induce reductions in health-related consumption. We used data on late middle age individuals (51-64 years) from the longitudinal US-based Health and Retirement Study (N=19 281) to examine the relationship between negative wealth shock and short-term outcomes that serve as markers of the pathways from wealth shock to health: elevated depressive symptoms, as a marker of the stress pathway and cost-related medication non-adherence (CRN), as a marker of the consumption pathway. Negative wealth shock was considered to be a loss of total net worth of 75% or more. Using a nested cross-over approach-a within-person design among exposed individuals only that adjusts by design for all time-invariant individual characteristics-we found that negative wealth shock was significantly associated with increased odds of elevated depressive symptoms (OR=1.50, CI 1.10 to 2.05), but was not significantly associated with higher odds of CRN (OR=1.18, CI 0.76 to 1.82), even after further adjustment for time-varying sociodemographic and health covariates. Negative wealth shock during late middle age confers an increased risk of elevated depressive symptoms, but does not change levels of CRN. Personal and policy factors that may buffer the mental health risks of negative wealth shock, such as social support and social welfare policy, should be considered. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Paternity testing a non-linkage based marker assisted selection scheme for outbred forage species
USDA-ARS?s Scientific Manuscript database
In many major perennial forage species, genomic tools and infrastructure development has advanced enough that their utilization in marker assisted selection (MAS) can be cheaply explored. This paper presents a paternity testing MAS in diploid red clover (Trifolium pratense L.). Utilizing individual ...
Using Next Generation Sequencing for Multiplexed Trait-Linked Markers in Wheat
Bernardo, Amy; Wang, Shan; St. Amand, Paul; Bai, Guihua
2015-01-01
With the advent of next generation sequencing (NGS) technologies, single nucleotide polymorphisms (SNPs) have become the major type of marker for genotyping in many crops. However, the availability of SNP markers for important traits of bread wheat ( Triticum aestivum L.) that can be effectively used in marker-assisted selection (MAS) is still limited and SNP assays for MAS are usually uniplex. A shift from uniplex to multiplex assays will allow the simultaneous analysis of multiple markers and increase MAS efficiency. We designed 33 locus-specific markers from SNP or indel-based marker sequences that linked to 20 different quantitative trait loci (QTL) or genes of agronomic importance in wheat and analyzed the amplicon sequences using an Ion Torrent Proton Sequencer and a custom allele detection pipeline to determine the genotypes of 24 selected germplasm accessions. Among the 33 markers, 27 were successfully multiplexed and 23 had 100% SNP call rates. Results from analysis of "kompetitive allele-specific PCR" (KASP) and sequence tagged site (STS) markers developed from the same loci fully verified the genotype calls of 23 markers. The NGS-based multiplexed assay developed in this study is suitable for rapid and high-throughput screening of SNPs and some indel-based markers in wheat. PMID:26625271
Exploring a new bilateral focal density asymmetry based image marker to predict breast cancer risk
NASA Astrophysics Data System (ADS)
Aghaei, Faranak; Mirniaharikandehei, Seyedehnafiseh; Hollingsworth, Alan B.; Wang, Yunzhi; Qiu, Yuchen; Liu, Hong; Zheng, Bin
2017-03-01
Although breast density has been widely considered an important breast cancer risk factor, it is not very effective to predict risk of developing breast cancer in a short-term or harboring cancer in mammograms. Based on our recent studies to build short-term breast cancer risk stratification models based on bilateral mammographic density asymmetry, we in this study explored a new quantitative image marker based on bilateral focal density asymmetry to predict the risk of harboring cancers in mammograms. For this purpose, we assembled a testing dataset involving 100 positive and 100 negative cases. In each of positive case, no any solid masses are visible on mammograms. We developed a computer-aided detection (CAD) scheme to automatically detect focal dense regions depicting on two bilateral mammograms of left and right breasts. CAD selects one focal dense region with the maximum size on each image and computes its asymmetrical ratio. We used this focal density asymmetry as a new imaging marker to divide testing cases into two groups of higher and lower focal density asymmetry. The first group included 70 cases in which 62.9% are positive, while the second group included 130 cases in which 43.1% are positive. The odds ratio is 2.24. As a result, this preliminary study supported the feasibility of applying a new focal density asymmetry based imaging marker to predict the risk of having mammography-occult cancers. The goal is to assist radiologists more effectively and accurately detect early subtle cancers using mammography and/or other adjunctive imaging modalities in the future.
Piotrowski, Wojciech J; Bieńkiewicz, Małgorzata; Frieske, Izabella; Marczak, Jerzy; Antczak, Adam; Górski, Paweł; Kuśmierek, Jacek; Płachcińska, Anna
2012-01-01
Discriminating between active and inactive sarcoidosis may be problematic in everyday clinical practice. There are numerous biochemical markers used in the diagnosis and monitoring of sarcoidosis. Somatostatin receptor (SR) scintigraphy with the use of 99mTc-octreotide may be used to estimate disease activity. The aim of the paper was to assess the value of traditional biomarkers (serum angiotensin-converting enzyme [SACE], C-reactive protein, markers of calcium metabolism, bronchoalveolar lavage fluid [BALF] lymphocytes) and a novel biomarker, 8-isoprostane (8-IP) in exhaled breath condensate (EBC), in the assessment of sarcoidosis activity in relation to somatostatin receptor scintigraphy. The study included 32 patients with sarcoidosis. Scintigraphy was performed using somatostatin analogue, 99mTc-HYNIC-TOC; planar and SPECT/CT images were recorded. The study group was divided into a subgroup with positive radiotracer uptake (n = 20) and without a visible uptake (n = 12). 8-IP levels were measured in EBC by an immunoenzymatic assay. RESULTS We observed a significantly higher EBC 8-IP levels in the subgroup with positive uptake compared with those with negative uptake (19.1 ± 19.8 vs. 5.4 ± 3.5 pg/ml, P = 0.02). The levels of SACE and the percentage of BALF lymphocytes were also nonsignificantly elevated. In the group of patients with positive scintigraphy results, a positive correlation was observed between the uptake ratio and SACE (r = 0.44, P = 0.041). The results indicate low value of biochemical markers in the assessment of disease activity. SR scintigraphy may have practical usefulness in the monitoring of sarcoidosis.
Node-Negative Breast Cancer: Which Patients Should Be Treated?
Schmidt, Marcus
2008-01-01
Summary Adjuvant systemic therapy has led to markedly improved outcome in early-stage breast cancer. However, the absolute gains from chemotherapy might be modest in node-negative patients. Adjuvant chemotherapy is the only option for triple-negative breast cancer patients and should be used with trastuzumab in HER2-positive patients. Considering the large group of patients with some degree of endocrine responsiveness, adding chemotherapy according to risk is an option. At present, we guide our therapeutic decisions using clinicopathologic risk classifications like the St. Gallen risk category or Adjuvant! online. A downside of these risk estimations is a low specificity and consequently the risk for overtreatment of a considerable number of patients. To spare patients unnecessary toxicities we need more reliable prognostic factors or tumor markers. From the plethora of tumor markers, only urokinase-type plasminogen activator (uPA)/plasminogen activator inhibitor 1 (PAI-1) and certain multiparameter gene expression assays are recommended by the American Society of Clinical Oncology. These tumor markers are presently investigated in clinical trials in node-negative breast cancer (NNBC-3, MINDACT, TAILORx). These studies will hopefully allow us to quantify the risk of progression in the individual patient and to tailor treatment accordingly. This should lead to a more personalized treatment recommendation. PMID:21076603
A Population Genetics Model of Marker-Assisted Selection
Luo, Z. W.; Thompson, R.; Woolliams, J. A.
1997-01-01
A deterministic two-loci model was developed to predict genetic response to marker-assisted selection (MAS) in one generation and in multiple generations. Formulas were derived to relate linkage disequilibrium in a population to the proportion of additive genetic variance used by MAS, and in turn to an extra improvement in genetic response over phenotypic selection. Predictions of the response were compared to those predicted by using an infinite-loci model and the factors affecting efficiency of MAS were examined. Theoretical analyses of the present study revealed the nonlinearity between the selection intensity and genetic response in MAS. In addition to the heritability of the trait and the proportion of the marker-associated genetic variance, the frequencies of the selectively favorable alleles at the two loci, one marker and one quantitative trait locus, were found to play an important role in determining both the short- and long-term efficiencies of MAS. The evolution of linkage disequilibrium and thus the genetic response over several generations were predicted theoretically and examined by simulation. MAS dissipated the disequilibrium more quickly than drift alone. In some cases studied, the rate of dissipation was as large as that to be expected in the circumstance where the true recombination fraction was increased by three times and selection was absent. PMID:9215918
Evaluation of the effect and profitability of gene-assisted selection in pig breeding system*
Li, Ya-lan; Zhang, Qin; Chen, Yao-sheng
2007-01-01
Objective: To evaluate the effect and profitability of using the quantitative trait loci (QTL)-linked direct marker (DR marker) in gene-assisted selection (GAS). Methods: Three populations (100, 200, or 300 sows plus 10 boars within each group) with segregating QTL were simulated stochastically. Five economic traits were investigated, including number of born alive (NBA), average daily gain to 100 kg body weight (ADG), feed conversion ratio (FCR), back fat at 100 kg body weight (BF) and intramuscular fat (IMF). Selection was based on the estimated breeding value (EBV) of each trait. The starting frequencies of the QTL’s favorable allele were 0.1, 0.3 and 0.5, respectively. The economic return was calculated by gene flow method. Results: The selection efficiency was higher than 100% when DR markers were used in GAS for 5 traits. The selection efficiency for NBA was the highest, and the lowest was for ADG whose QTL had the lowest variance. The mixed model applied DR markers and obtained higher extra genetic gain and extra economic returns. We also found that the lower the frequency of the favorable allele of the QTL, the higher the extra return obtained. Conclusion: GAS is an effective selection scheme to increase the genetic gain and the economic returns in pig breeding. PMID:17973344
Evaluation of the effect and profitability of gene-assisted selection in pig breeding system.
Li, Ya-Lan; Zhang, Qin; Chen, Yao-Sheng
2007-11-01
To evaluate the effect and profitability of using the quantitative trait loci (QTL)-linked direct marker (DR marker) in gene-assisted selection (GAS). Three populations (100, 200, or 300 sows plus 10 boars within each group) with segregating QTL were simulated stochastically. Five economic traits were investigated, including number of born alive (NBA), average daily gain to 100 kg body weight (ADG), feed conversion ratio (FCR), back fat at 100 kg body weight (BF) and intramuscular fat (IMF). Selection was based on the estimated breeding value (EBV) of each trait. The starting frequencies of the QTL's favorable allele were 0.1, 0.3 and 0.5, respectively. The economic return was calculated by gene flow method. The selection efficiency was higher than 100% when DR markers were used in GAS for 5 traits. The selection efficiency for NBA was the highest, and the lowest was for ADG whose QTL had the lowest variance. The mixed model applied DR markers and obtained higher extra genetic gain and extra economic returns. We also found that the lower the frequency of the favorable allele of the QTL, the higher the extra return obtained. GAS is an effective selection scheme to increase the genetic gain and the economic returns in pig breeding.
Samadder, N Jewel; Vierkant, Robert A; Tillmans, Lori S; Wang, Alice H; Weisenberger, Daniel J; Laird, Peter W; Lynch, Charles F; Anderson, Kristin E; French, Amy J; Haile, Robert W; Potter, John D; Slager, Susan L; Smyrk, Thomas C; Thibodeau, Stephen N; Cerhan, James R; Limburg, Paul J
2013-08-01
Colorectal tumors have a large degree of molecular heterogeneity. Three integrated pathways of carcinogenesis (ie, traditional, alternate, and serrated) have been proposed, based on specific combinations of microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and mutations in BRAF and KRAS. We used resources from the population-based Iowa Women's Health Study (n = 41,836) to associate markers of colorectal tumors, integrated pathways, and clinical and pathology characteristics, including survival times. We assessed archived specimens from 732 incident colorectal tumors and characterized them as microsatellite stable (MSS), MSI high or MSI low, CIMP high or CIMP low, CIMP negative, and positive or negative for BRAF and/or KRAS mutations. Informative marker data were collected from 563 tumors (77%), which were assigned to the following integrated pathways: traditional (MSS, CIMP negative, BRAF mutation negative, and KRAS mutation negative; n = 170), alternate (MSS, CIMP low, BRAF mutation negative, and KRAS mutation positive; n = 58), serrated (any MSI, CIMP high, BRAF mutation positive, and KRAS mutation negative; n = 142), or unassigned (n = 193). Multivariable-adjusted Cox proportional hazards regression models were used to assess the associations of interest. Patients' mean age (P = .03) and tumors' anatomic subsite (P = .0001) and grade (P = .0001) were significantly associated with integrated pathway assignment. Colorectal cancer (CRC) mortality was not associated with the traditional, alternate, or serrated pathways, but was associated with a subset of pathway-unassigned tumors (MSS or MSI low, CIMP negative, BRAF mutation negative, and KRAS mutation positive) (n = 96 cases; relative risk = 1.76; 95% confidence interval, 1.07-2.89, compared with the traditional pathway). We identified clinical and pathology features associated with molecularly defined CRC subtypes. However, additional studies are needed to determine how these features might influence prognosis. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.
Lamiquiz-Moneo, Itziar; Baila-Rueda, Lucía; Bea, Ana M; Mateo-Gallego, Rocío; Pérez-Calahorra, Sofía; Marco-Benedí, Victoria; Martín-Navarro, Antonio; Ros, Emilio; Cofán, Montserrat; Rodríguez-Rey, José Carlos; Pocovi, Miguel; Cenarro, Ana; Civeira, Fernando
Approximately 20% to 40% of clinically defined familial hypercholesterolemia (FH) cases do not show a causative mutation in candidate genes (mutation-negative FH), and some of them may have a polygenic origin. The aim of this work was to study the prevalence of ABCG5/G8 genetic variants in mutation-negative FH, as defects in these genes relate to intestinal hyperabsorption of cholesterol and thus ABCG5/G8 variants could explain in part the mechanism of hypercholesterolemia. We sequenced the ABCG5/G8 genes in 214 mutation-negative FH and 97 controls. Surrogate markers of cholesterol absorption (5α-cholestanol, β-sitosterol, campesterol, stigmasterol, and sitostanol) were quantified by high-performance liquid chromatography-tandem mass spectrometry in both studied groups. We found 8 mutation-negative FH patients (3.73%) with a pathogenic mutation in ABCG5/G8 genes. We observed significantly higher concentration of surrogate markers of cholesterol absorption in mutation-negative FH than in controls. In addition, we found significantly higher concentrations of cholesterol absorption markers in mutation-negative FH with ABCG5/G8 defects than in mutation-negative, ABCG5/G8-negative FH. A gene score reflecting the number of common single nucleotide variants associated with hypercholesterolemia was significantly higher in cases than in controls (P = .032). Subjects with a gene score above the mean had significantly higher 5α-cholestanol and stigmasterol than those with a lower gene score. Mutation-negative FH subjects accumulate an excess of rare and common gene variations in ABCG5/G8 genes. This variation is associated with increased intestinal absorption of cholesterol, as determined by surrogate makers, suggesting that these loci contribute to hypercholesterolemia by enhancing intestinal cholesterol absorption. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.
Zhang, Silai; Ban, Akihiko; Ebara, Naoki; Mizutani, Osamu; Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya
2017-04-01
In this study, we developed a self-excising Cre/loxP-mediated marker recycling system with mutated lox sequences to introduce a number of biosynthetic genes into Aspergillus oryzae. To construct the self-excising marker cassette, both the selectable marker, the Aspergillus nidulans adeA gene, and the Cre recombinase gene (cre), conditionally expressed by the xylanase-encoding gene promoter, were designed to be located between the mutant lox sequences, lox66 and lox71. However, construction of the plasmid failed, possibly owing to a slight expression of cre downstream of the fungal gene promoter in Escherichia coli. Hence, to avoid the excision of the cassette in E. coli, a 71-bp intron of the A. oryzae xynG2 gene was inserted into the cre gene. The A. oryzae adeA deletion mutant was transformed with the resulting plasmid in the presence of glucose, and the transformants were cultured in medium containing xylose as the sole carbon source. PCR analysis of genomic DNA from resultant colonies revealed the excision of both the marker and Cre expression construct, indicating that the self-excising marker cassette was efficient at removing the selectable marker. Using the marker recycling system, hyperproduction of kojic acid could be achieved in A. oryzae by the introduction of two genes that encode oxidoreductase and transporter. Furthermore, we also constructed an alternative marker recycling cassette bearing the A. nidulans pyrithiamine resistant gene (ptrA) as a dominant selectable marker. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Sensory Processing Sensitivity as a Marker of Differential Susceptibility to Parenting
ERIC Educational Resources Information Center
Slagt, Meike; Dubas, Judith Semon; van Aken, Marcel A. G.; Ellis, Bruce J.; Dekovic, Maja
2018-01-01
In this longitudinal multiinformant study negative emotionality and sensory processing sensitivity were compared as susceptibility markers among kindergartners. Participating children (N = 264, 52.9% boys) were Dutch kindergartners (M[subscript age] = 4.77, SD = 0.60), followed across three waves, spaced seven months apart. Results show that…
Ostrowska, Zofia; Świętochowska, Elżbieta; Marek, Bogdan; Kajdaniuk, Dariusz; Tyrpień-Golder, Krystyna; Wołkowska-Pokrywa, Kinga; Damasiewicz-Bodzek, Aleksandra; Kos-Kudła, Beata
2014-01-01
It has been suggested that changes in the production of adipose tissue hormones in obese postmenopausal women might affect their bone status. The aim of this study was to determine whether obese postmenopausal women exhibited any relationship between serum levels of LP, ADIPO, RES, VISF, APE and bone metabolism markers (OC and CTx), OPG, sRANKL, the OPG/sRANKL ratio as well as BMD. 80 postmenopausal women (60 obese and 20 healthy) underwent BMD measurement using dual-energy X-ray absorptiometry (DXA) at lumbar spine L2-L4. Serum levels of selected adipose tissue hormones, OC, CTx, OPG and its soluble ligand, sRANKL, were assessed by ELISA. Obese postmenopausal women demonstrated a significant increase in body mass, BMI and WHR associated with significant increases in LP and RES levels, a decrease in ADIPO concentration, suppression of OC, CTx, OPG and sRANKL and an increase in the OPG/sRANKL ratio and BMD. BMI correlated positively with BMD, LP, RES, OPG and the OPG/sRANKL ratio, whereas in the case of ADIPO, OC, CTx, sRANKL the relationship was negative. WHR was positively correlated with the OPG/sRANKL ratio, and negatively with ADIPO and APE. A positive correlation was found between BMD and LP, APE and the OPG/sRANKL ratio, while the correlation between BMD and ADIPO, CTx, sRANKL was negative. Significant positive correlations were also revealed between OC, CTx and ADIPO; OPG and ADIPO; sRANKL and ADIPO, RES; the OPG/sRANKL ratio and LP. OC correlated negatively with LP, RES, VISF, APE; CTx with LP, VISF, APE; OPG with LP; sRANKL with LP and APE; the OPG/sRANKL ratio with VISF. ADIPO was an independent predictor of OC, OPG and sRANKL, while LP turned out to be an independent predictor of CTx, OPG, sRANKL and the OPG/sRANKL ratio. Obesity in postmenopausal women can lead to changes in BMD, circulating levels of bone markers, OPG, sRANKL and/or the OPG/sRANKL ratio; these changes are associated with alterations in the concentrations of adipose tissue hormones under investigation. The relationships between bone status indicators and adipose tissue hormones, especially LP and ADIPO, seem to suggest that changes in these hormones observed in obese postmenopausal women might have a protective effect on bone tissue, most probably via a shift in the OPG/sRANKL ratio towards a functional excess of OPG.
Tracing Asian Seabass Individuals to Single Fish Farms Using Microsatellites
Yue, Gen Hua; Xia, Jun Hong; Liu, Peng; Liu, Feng; Sun, Fei; Lin, Grace
2012-01-01
Traceability through physical labels is well established, but it is not highly reliable as physical labels can be easily changed or lost. Application of DNA markers to the traceability of food plays an increasingly important role for consumer protection and confidence building. In this study, we tested the efficiency of 16 polymorphic microsatellites and their combinations for tracing 368 fish to four populations where they originated. Using the maximum likelihood and Bayesian methods, three most efficient microsatellites were required to assign over 95% of fish to the correct populations. Selection of markers based on the assignment score estimated with the software WHICHLOCI was most effective in choosing markers for individual assignment, followed by the selection based on the allele number of individual markers. By combining rapid DNA extraction, and high-throughput genotyping of selected microsatellites, it is possible to conduct routine genetic traceability with high accuracy in Asian seabass. PMID:23285169
Szumilewicz, Anna; Worska, Aneta; Piernicka, Magdalena; Kuchta, Agnieszka; Kortas, Jakub; Jastrzębski, Zbigniew; Radzimiński, Łukasz; Jaworska, Joanna; Micielska, Katarzyna; Ziemann, Ewa
2017-01-01
Both exercise and pregnancy influence serum irisin concentration. To determine how the interaction of pregnancy and exercise affects irisin level and whether various patterns of exercise adherence had different effect on irisin concentration. It was a one-group pretest-posttest study among 9 Caucasian nulliparous healthy women in normal pregnancy (age 23 ± 3 years, 21 ± 2 weeks of gestation; mean ± SD) who participated in 8-week group fitness program. Before and after exercise intervention, we determined serum concentrations of irisin and selected parameters of lipid profile and glucose homeostasis markers. In active women, irisin slightly decreased with the development of pregnancy. After 8 weeks of exercising, irisin correlated negatively with fasting glucose ( R = -0.922; p = 0.001), glycated hemoglobin ( R = -0.784; p = 0.012), and insulin concentrations ( R = -0.845; p = 0.004). In women exercising below recommended level, we observed a significant drop in irisin concentration, whereas in women exercising at least three times a week this myokine slightly increased (31% difference; 90% confidence limits ±28; a large, clear effect). Irisin stimulated by prenatal exercise may improve glucose homeostasis markers in healthy women and compensate for metabolic changes induced by pregnancy. Moreover, the frequency of exercise may regulate the changes in exercise-induced irisin concentration.
Zhang, Shuai; Guo, Yuanming; Yan, Zhongyong; Sun, Xiumei; Zhang, Xiaojun
2015-12-01
Reliably detecting nitrofurazone (NFZ) residues in farmed crab and shrimp was previously hindered by lack of appropriately specific analytical methodology. Parent NFZ rapidly breaks down in meat, and the commonly used side-chain metabolite, semicarbazide (SEM), is non-specific as it occurs naturally in crustacean shell often leading to 'false positive' detections in meat. Using 5-nitro-2-furaldehyde (NF) as marker metabolite, following pre-column derivatization with 2,4-dinitrophenylhydrazine (DNPH), ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis in negative electrospray ionization mode enabled confirmation of NFZ residues in deliberately treated whole crab, crab meat and shrimp meat, with a limit of detection (LOD) and limit of quantification (LOQ) below 1 ng g(-1). Meanwhile, the derivatives of DNPH-NF were synthesized for the first time, purified by preparative liquid chromatography and structure characterized with nuclear magnetic resonance spectroscopy ((1)H-NMR). The purity of derivative was checked by ultra-performance liquid chromatography-tunable ultraviolet (UPLC-TUV), and the contents were beyond 99.9%. For comparison purposes, crustacean samples were analysed using both NF and SEM marker metabolites. NFZ treatment was revealed by both NF and SEM marker metabolites, but untreated crab also showed measurable levels of SEM which could potentially be misinterpreted as evidence of illegal NFZ use.
Zaki, Noorhariza Mohd; Singh, Rajinder; Rosli, Rozana; Ismail, Ismanizan
2012-01-01
Species-specific simple sequence repeat (SSR) markers are favored for genetic studies and marker-assisted selection (MAS) breeding for oil palm genetic improvement. This report characterizes 20 SSR markers from an Elaeis oleifera genomic library (gSSR). Characterization of the repeat type in 2000 sequences revealed a high percentage of di-nucleotides (63.6%), followed by tri-nucleotides (24.2%). Primer pairs were successfully designed for 394 of the E. oleifera gSSRs. Subsequent analysis showed the ability of the 20 selected E. oleifera gSSR markers to reveal genetic diversity in the genus Elaeis. The average Polymorphism Information Content (PIC) value for the SSRs was 0.402, with the tri-repeats showing the highest average PIC (0.626). Low values of observed heterozygosity (Ho) (0.164) and highly positive fixation indices (Fis) in the E. oleifera germplasm collection, compared to the E. guineensis, indicated an excess of homozygosity in E. oleifera. The transferability of the markers to closely related palms, Elaeis guineensis, Cocos nucifera and ornamental palms is also reported. Sequencing the amplicons of three selected E. oleifera gSSRs across both species and palm taxa revealed variations in the repeat-units. The study showed the potential of E. oleifera gSSR markers to reveal genetic diversity in the genus Elaeis. The markers are also a valuable genetic resource for studying E. oleifera and other genus in the Arecaceae family. PMID:22605966
Agrawal, Aneil F.; Hartfield, Matthew
2016-01-01
Uniparental reproduction in diploids, via asexual reproduction or selfing, reduces the independence with which separate loci are transmitted across generations. This is expected to increase the extent to which a neutral marker is affected by selection elsewhere in the genome. Such effects have previously been quantified in coalescent models involving selfing. Here we examine the effects of background selection and balancing selection in diploids capable of both sexual and asexual reproduction (i.e., partial asexuality). We find that the effect of background selection on reducing coalescent time (and effective population size) can be orders of magnitude greater when rates of sex are low than when sex is common. This is because asexuality enhances the effects of background selection through both a recombination effect and a segregation effect. We show that there are several reasons that the strength of background selection differs between systems with partial asexuality and those with comparable levels of uniparental reproduction via selfing. Expectations for reductions in Ne via background selection have been verified using stochastic simulations. In contrast to background selection, balancing selection increases the coalescence time for a linked neutral site. With partial asexuality, the effect of balancing selection is somewhat dependent upon the mode of selection (e.g., heterozygote advantage vs. negative frequency-dependent selection) in a manner that does not apply to selfing. This is because the frequency of heterozygotes, which are required for recombination onto alternative genetic backgrounds, is more dependent on the pattern of selection with partial asexuality than with selfing. PMID:26584901
Agrawal, Aneil F; Hartfield, Matthew
2016-01-01
Uniparental reproduction in diploids, via asexual reproduction or selfing, reduces the independence with which separate loci are transmitted across generations. This is expected to increase the extent to which a neutral marker is affected by selection elsewhere in the genome. Such effects have previously been quantified in coalescent models involving selfing. Here we examine the effects of background selection and balancing selection in diploids capable of both sexual and asexual reproduction (i.e., partial asexuality). We find that the effect of background selection on reducing coalescent time (and effective population size) can be orders of magnitude greater when rates of sex are low than when sex is common. This is because asexuality enhances the effects of background selection through both a recombination effect and a segregation effect. We show that there are several reasons that the strength of background selection differs between systems with partial asexuality and those with comparable levels of uniparental reproduction via selfing. Expectations for reductions in Ne via background selection have been verified using stochastic simulations. In contrast to background selection, balancing selection increases the coalescence time for a linked neutral site. With partial asexuality, the effect of balancing selection is somewhat dependent upon the mode of selection (e.g., heterozygote advantage vs. negative frequency-dependent selection) in a manner that does not apply to selfing. This is because the frequency of heterozygotes, which are required for recombination onto alternative genetic backgrounds, is more dependent on the pattern of selection with partial asexuality than with selfing. Copyright © 2016 by the Genetics Society of America.
Verification of STS markers for leaf rust resistance genes of wheat by seven European laboratories.
Błaszczyk, Lidia; Chełkowski, Jerzy; Korzun, Victor; Kraic, Jan; Ordon, Frank; Ovesná, Jaroslava; Purnhauser, Laszlo; Tar, Melinda; Vida, Gyula
2004-01-01
A set of Thatcher near-isogenic lines and two breeding lines were used to examine sequence tagged site (STS) markers linked to leaf rust resistance genes Lr9, Lr10, Lr19, Lr24, Lr28, Lr29, Lr35, and a simple sequenced repeat (SSR) marker for Lr39. The selected STS markers for resistance genes Lr9, Lr10, Lr19, Lr24 and Lr28 were identified in seven accessions by seven European laboratories. Near-isogenic lines of the spring wheat Thatcher were used as positive controls. Markers for resistance genes Lr9, Lr10, Lr19, Lr24 were identified in all seven laboratories as amplification products of 1100 bp, 310 bp, 130 bp and 310 bp, respectively. The STS markers linked to resistance genes Lr9, Lr10, Lr19, Lr24, Lr29, Lr35 and the SSR marker for Lr39 were robust and highly specific for these genes and will be useful in marker-assisted selection in wheat. However, the amplification product of 378 bp that corresponded with resistance gene Lr28 was detected in all accessions including genotypes lacking this gene in all seven laboratories. This marker needs to be improved.
Genome wide selection in Citrus breeding.
Gois, I B; Borém, A; Cristofani-Yaly, M; de Resende, M D V; Azevedo, C F; Bastianel, M; Novelli, V M; Machado, M A
2016-10-17
Genome wide selection (GWS) is essential for the genetic improvement of perennial species such as Citrus because of its ability to increase gain per unit time and to enable the efficient selection of characteristics with low heritability. This study assessed GWS efficiency in a population of Citrus and compared it with selection based on phenotypic data. A total of 180 individual trees from a cross between Pera sweet orange (Citrus sinensis Osbeck) and Murcott tangor (Citrus sinensis Osbeck x Citrus reticulata Blanco) were evaluated for 10 characteristics related to fruit quality. The hybrids were genotyped using 5287 DArT_seq TM (diversity arrays technology) molecular markers and their effects on phenotypes were predicted using the random regression - best linear unbiased predictor (rr-BLUP) method. The predictive ability, prediction bias, and accuracy of GWS were estimated to verify its effectiveness for phenotype prediction. The proportion of genetic variance explained by the markers was also computed. The heritability of the traits, as determined by markers, was 16-28%. The predictive ability of these markers ranged from 0.53 to 0.64, and the regression coefficients between predicted and observed phenotypes were close to unity. Over 35% of the genetic variance was accounted for by the markers. Accuracy estimates with GWS were lower than those obtained by phenotypic analysis; however, GWS was superior in terms of genetic gain per unit time. Thus, GWS may be useful for Citrus breeding as it can predict phenotypes early and accurately, and reduce the length of the selection cycle. This study demonstrates the feasibility of genomic selection in Citrus.
Integrative Analysis of High-throughput Cancer Studies with Contrasted Penalization
Shi, Xingjie; Liu, Jin; Huang, Jian; Zhou, Yong; Shia, BenChang; Ma, Shuangge
2015-01-01
In cancer studies with high-throughput genetic and genomic measurements, integrative analysis provides a way to effectively pool and analyze heterogeneous raw data from multiple independent studies and outperforms “classic” meta-analysis and single-dataset analysis. When marker selection is of interest, the genetic basis of multiple datasets can be described using the homogeneity model or the heterogeneity model. In this study, we consider marker selection under the heterogeneity model, which includes the homogeneity model as a special case and can be more flexible. Penalization methods have been developed in the literature for marker selection. This study advances from the published ones by introducing the contrast penalties, which can accommodate the within- and across-dataset structures of covariates/regression coefficients and, by doing so, further improve marker selection performance. Specifically, we develop a penalization method that accommodates the across-dataset structures by smoothing over regression coefficients. An effective iterative algorithm, which calls an inner coordinate descent iteration, is developed. Simulation shows that the proposed method outperforms the benchmark with more accurate marker identification. The analysis of breast cancer and lung cancer prognosis studies with gene expression measurements shows that the proposed method identifies genes different from those using the benchmark and has better prediction performance. PMID:24395534
Niklaus, Michael; Gruissem, Wilhelm; Vanderschuren, Hervé
2011-01-01
Cassava is one of the most important crops in the tropics. Its industrial use for starch and biofuel production is also increasing its importance for agricultural production in tropical countries. In the last decade cassava biotechnology has emerged as a valuable alternative to the breeding constraints of this highly heterozygous crop for improved trait development of cassava germplasm. Cassava transformation remains difficult and time-consuming because of limitations in selecting transgenic tissues and regeneration of transgenic plantlets. We have recently reported an efficient and robust cassava transformation protocol using the hygromycin phosphotransferase II (hptII) gene as selection marker and the aminoglycoside hygromycin at optimal concentrations to maximize the regeneration of transgenic plantlets. In the present work, we expanded the transformation protocol to the use of the neomycin phosphotransferase II (nptII) gene as selection marker. Several aminoglycosides compatible with the use of nptII were tested and optimal concentrations for cassava transformation were determined. Given its efficiency equivalent to hptII as selection marker with the described protocol, the use of nptII opens new possibilities to engineer transgenic cassava lines with multiple T-DNA insertions and to produce transgenic cassava with a resistance marker gene that is already deregulated in several commercial transgenic crops.
Cao, Li-Jun; Li, Ze-Min; Wang, Ze-Hua; Zhu, Liang; Gong, Ya-Jun; Chen, Min; Wei, Shu-Jun
2016-01-01
Recent improvements in next-generation sequencing technologies have enabled investigation of microsatellites on a genome-wide scale. Faced with a huge amount of candidates, the use of appropriate marker selection criteria is crucial. Here, we used the western flower thrips Frankliniella occidentalis for an empirical microsatellite survey and validation; 132,251 candidate microsatellites were identified, 92,102 of which were perfect. Dinucleotides were the most abundant category, while (AG)n was the most abundant motif. Sixty primer pairs were designed and validated in two natural populations, of which 30 loci were polymorphic, stable, and repeatable, but not all in Hardy–Weinberg equilibrium (HWE) and linkage equilibrium. Four marker panels were constructed to understand effect of marker selection on population genetic analyses: (i) only accept loci with single nucleotide insertions (SNI); (ii) only accept the most polymorphic loci (MP); (iii) only accept loci that did not deviate from HWE, did not show SNIs, and had unambiguous peaks (SS) and (iv) all developed markers (ALL). Although the MP panel resulted in microsatellites of highest genetic diversity followed by the SNI, the SS performed best in individual assignment. Our study proposes stringent criteria for selection of microsatellites from a large-scale number of genomic candidates for population genetic studies. PMID:27197749
Cao, Li-Jun; Li, Ze-Min; Wang, Ze-Hua; Zhu, Liang; Gong, Ya-Jun; Chen, Min; Wei, Shu-Jun
2016-05-20
Recent improvements in next-generation sequencing technologies have enabled investigation of microsatellites on a genome-wide scale. Faced with a huge amount of candidates, the use of appropriate marker selection criteria is crucial. Here, we used the western flower thrips Frankliniella occidentalis for an empirical microsatellite survey and validation; 132,251 candidate microsatellites were identified, 92,102 of which were perfect. Dinucleotides were the most abundant category, while (AG)n was the most abundant motif. Sixty primer pairs were designed and validated in two natural populations, of which 30 loci were polymorphic, stable, and repeatable, but not all in Hardy-Weinberg equilibrium (HWE) and linkage equilibrium. Four marker panels were constructed to understand effect of marker selection on population genetic analyses: (i) only accept loci with single nucleotide insertions (SNI); (ii) only accept the most polymorphic loci (MP); (iii) only accept loci that did not deviate from HWE, did not show SNIs, and had unambiguous peaks (SS) and (iv) all developed markers (ALL). Although the MP panel resulted in microsatellites of highest genetic diversity followed by the SNI, the SS performed best in individual assignment. Our study proposes stringent criteria for selection of microsatellites from a large-scale number of genomic candidates for population genetic studies.
Mueller, Jutta L; Hirotani, Masako; Friederici, Angela D
2007-01-01
Background The present experiments were designed to test how the linguistic feature of case is processed in Japanese by native and non-native listeners. We used a miniature version of Japanese as a model to compare sentence comprehension mechanisms in native speakers and non-native learners who had received training until they had mastered the system. In the first experiment we auditorily presented native Japanese speakers with sentences containing incorrect double nominatives and incorrect double accusatives, and with correct sentences. In the second experiment we tested trained non-natives with the same material. Based on previous research in German we expected an N400-P600 biphasic ERP response with specific modulations depending on the violated case and whether the listeners were native or non-native. Results For native Japanese participants the general ERP response to the case violations was an N400-P600 pattern. Double accusatives led to an additional enhancement of the P600 amplitude. For the learners a native-like P600 was present for double accusatives and for double nominatives. The additional negativity, however, was present in learners only for double nominative violations, and it was characterized by a different topographical distribution. Conclusion The results indicate that native listeners use case markers for thematic as well as syntactic structure building during incremental sentence interpretation. The modulation of the P600 component for double accusatives possibly reflects case specific syntactic restrictions in Japanese. For adult language learners later processes, as reflected in the P600, seem to be more native-like compared to earlier processes. The anterior distribution of the negativity and its selective emergence for canonical sentences were taken to suggest that the non-native learners resorted to a rather formal processing strategy whereby they relied to a large degree on the phonologically salient nominative case marker. PMID:17331265
Campbell, Nathan R.; LaPatra, Scott E.; Overturf, Ken; Towner, Richard; Narum, Shawn R.
2014-01-01
Recent advances in genotyping-by-sequencing have enabled genome-wide association studies in nonmodel species including those in aquaculture programs. As with other aquaculture species, rainbow trout and steelhead (Oncorhynchus mykiss) are susceptible to disease and outbreaks can lead to significant losses. Fish culturists have therefore been pursuing strategies to prevent losses to common pathogens such as Flavobacterium psychrophilum (the etiological agent for bacterial cold water disease [CWD]) and infectious hematopoietic necrosis virus (IHNV) by adjusting feed formulations, vaccine development, and selective breeding. However, discovery of genetic markers linked to disease resistance offers the potential to use marker-assisted selection to increase resistance and reduce outbreaks. For this study we sampled juvenile fish from 40 families from 2-yr classes that either survived or died after controlled exposure to either CWD or IHNV. Restriction site−associated DNA sequencing produced 4661 polymorphic single-nucleotide polymorphism loci after strict filtering. Genotypes from individual survivors and mortalities were then used to test for association between disease resistance and genotype at each locus using the program TASSEL. After we accounted for kinship and stratification of the samples, tests revealed 12 single-nucleotide polymorphism markers that were highly associated with resistance to CWD and 19 markers associated with resistance to IHNV. These markers are candidates for further investigation and are expected to be useful for marker assisted selection in future broodstock selection for various aquaculture programs. PMID:25354781
Cuenca, Jose; Aleza, Pablo; Garcia-Lor, Andres; Ollitrault, Patrick; Navarro, Luis
2016-01-01
Alternaria brown spot (ABS) is a serious disease affecting susceptible citrus genotypes, which is a strong concern regarding citrus breeding programs. Resistance is conferred by a recessive locus (ABSr) previously located by our group within a 3.3 Mb genome region near the centromere in chromosome III. This work addresses fine-linkage mapping of this region for identifying candidate resistance genes and develops new molecular markers for ABS-resistance effective marker-assisted selection (MAS). Markers closely linked to ABSr locus were used for fine mapping using a 268-segregating diploid progeny derived from a heterozygous susceptible × resistant cross. Fine mapping limited the genomic region containing the ABSr resistance gene to 366 kb, flanked by markers at 0.4 and 0.7 cM. This region contains nine genes related to pathogen resistance. Among them, eight are resistance (R) gene homologs, with two of them harboring a serine/threonine protein kinase domain. These two genes along with a gene encoding a S-adenosyl-L-methionine-dependent-methyltransferase protein, should be considered as strong candidates for ABS-resistance. Moreover, the closest SNP was genotyped in 40 citrus varieties, revealing very high association with the resistant/susceptible phenotype. This new marker is currently used in our citrus breeding program for ABS-resistant parent and cultivar selection, at diploid, triploid and tetraploid level. PMID:28066498
Bouchet, Sophie; Pot, David; Deu, Monique; Rami, Jean-François; Billot, Claire; Perrier, Xavier; Rivallan, Ronan; Gardes, Laëtitia; Xia, Ling; Wenzl, Peter; Kilian, Andrzej; Glaszmann, Jean-Christophe
2012-01-01
Population structure, extent of linkage disequilibrium (LD) as well as signatures of selection were investigated in sorghum using a core sample representative of worldwide diversity. A total of 177 accessions were genotyped with 1122 informative physically anchored DArT markers. The properties of DArTs to describe sorghum genetic structure were compared to those of SSRs and of previously published RFLP markers. Model-based (STRUCTURE software) and Neighbor-Joining diversity analyses led to the identification of 6 groups and confirmed previous evolutionary hypotheses. Results were globally consistent between the different marker systems. However, DArTs appeared more robust in terms of data resolution and bayesian group assignment. Whole genome linkage disequilibrium as measured by mean r2 decreased from 0.18 (between 0 to 10 kb) to 0.03 (between 100 kb to 1 Mb), stabilizing at 0.03 after 1 Mb. Effects on LD estimations of sample size and genetic structure were tested using i. random sampling, ii. the Maximum Length SubTree algorithm (MLST), and iii. structure groups. Optimizing population composition by the MLST reduced the biases in small samples and seemed to be an efficient way of selecting samples to make the best use of LD as a genome mapping approach in structured populations. These results also suggested that more than 100,000 markers may be required to perform genome-wide association studies in collections covering worldwide sorghum diversity. Analysis of DArT markers differentiation between the identified genetic groups pointed out outlier loci potentially linked to genes controlling traits of interest, including disease resistance genes for which evidence of selection had already been reported. In addition, evidence of selection near a homologous locus of FAR1 concurred with sorghum phenotypic diversity for sensitivity to photoperiod. PMID:22428056
Juliana, Philomin; Singh, Ravi P; Singh, Pawan K; Crossa, Jose; Rutkoski, Jessica E; Poland, Jesse A; Bergstrom, Gary C; Sorrells, Mark E
2017-07-01
The leaf spotting diseases in wheat that include Septoria tritici blotch (STB) caused by , Stagonospora nodorum blotch (SNB) caused by , and tan spot (TS) caused by pose challenges to breeding programs in selecting for resistance. A promising approach that could enable selection prior to phenotyping is genomic selection that uses genome-wide markers to estimate breeding values (BVs) for quantitative traits. To evaluate this approach for seedling and/or adult plant resistance (APR) to STB, SNB, and TS, we compared the predictive ability of least-squares (LS) approach with genomic-enabled prediction models including genomic best linear unbiased predictor (GBLUP), Bayesian ridge regression (BRR), Bayes A (BA), Bayes B (BB), Bayes Cπ (BC), Bayesian least absolute shrinkage and selection operator (BL), and reproducing kernel Hilbert spaces markers (RKHS-M), a pedigree-based model (RKHS-P) and RKHS markers and pedigree (RKHS-MP). We observed that LS gave the lowest prediction accuracies and RKHS-MP, the highest. The genomic-enabled prediction models and RKHS-P gave similar accuracies. The increase in accuracy using genomic prediction models over LS was 48%. The mean genomic prediction accuracies were 0.45 for STB (APR), 0.55 for SNB (seedling), 0.66 for TS (seedling) and 0.48 for TS (APR). We also compared markers from two whole-genome profiling approaches: genotyping by sequencing (GBS) and diversity arrays technology sequencing (DArTseq) for prediction. While, GBS markers performed slightly better than DArTseq, combining markers from the two approaches did not improve accuracies. We conclude that implementing GS in breeding for these diseases would help to achieve higher accuracies and rapid gains from selection. Copyright © 2017 Crop Science Society of America.
Bouchet, Sophie; Pot, David; Deu, Monique; Rami, Jean-François; Billot, Claire; Perrier, Xavier; Rivallan, Ronan; Gardes, Laëtitia; Xia, Ling; Wenzl, Peter; Kilian, Andrzej; Glaszmann, Jean-Christophe
2012-01-01
Population structure, extent of linkage disequilibrium (LD) as well as signatures of selection were investigated in sorghum using a core sample representative of worldwide diversity. A total of 177 accessions were genotyped with 1122 informative physically anchored DArT markers. The properties of DArTs to describe sorghum genetic structure were compared to those of SSRs and of previously published RFLP markers. Model-based (STRUCTURE software) and Neighbor-Joining diversity analyses led to the identification of 6 groups and confirmed previous evolutionary hypotheses. Results were globally consistent between the different marker systems. However, DArTs appeared more robust in terms of data resolution and bayesian group assignment. Whole genome linkage disequilibrium as measured by mean r(2) decreased from 0.18 (between 0 to 10 kb) to 0.03 (between 100 kb to 1 Mb), stabilizing at 0.03 after 1 Mb. Effects on LD estimations of sample size and genetic structure were tested using i. random sampling, ii. the Maximum Length SubTree algorithm (MLST), and iii. structure groups. Optimizing population composition by the MLST reduced the biases in small samples and seemed to be an efficient way of selecting samples to make the best use of LD as a genome mapping approach in structured populations. These results also suggested that more than 100,000 markers may be required to perform genome-wide association studies in collections covering worldwide sorghum diversity. Analysis of DArT markers differentiation between the identified genetic groups pointed out outlier loci potentially linked to genes controlling traits of interest, including disease resistance genes for which evidence of selection had already been reported. In addition, evidence of selection near a homologous locus of FAR1 concurred with sorghum phenotypic diversity for sensitivity to photoperiod.
RNA-Seq identifies SNP markers for growth traits in rainbow trout.
Salem, Mohamed; Vallejo, Roger L; Leeds, Timothy D; Palti, Yniv; Liu, Sixin; Sabbagh, Annas; Rexroad, Caird E; Yao, Jianbo
2012-01-01
Fast growth is an important and highly desired trait, which affects the profitability of food animal production, with feed costs accounting for the largest proportion of production costs. Traditional phenotype-based selection is typically used to select for growth traits; however, genetic improvement is slow over generations. Single nucleotide polymorphisms (SNPs) explain 90% of the genetic differences between individuals; therefore, they are most suitable for genetic evaluation and strategies that employ molecular genetics for selective breeding. SNPs found within or near a coding sequence are of particular interest because they are more likely to alter the biological function of a protein. We aimed to use SNPs to identify markers and genes associated with genetic variation in growth. RNA-Seq whole-transcriptome analysis of pooled cDNA samples from a population of rainbow trout selected for improved growth versus unselected genetic cohorts (10 fish from 1 full-sib family each) identified SNP markers associated with growth-rate. The allelic imbalances (the ratio between the allele frequencies of the fast growing sample and that of the slow growing sample) were considered at scores >5.0 as an amplification and <0.2 as loss of heterozygosity. A subset of SNPs (n = 54) were validated and evaluated for association with growth traits in 778 individuals of a three-generation parent/offspring panel representing 40 families. Twenty-two SNP markers and one mitochondrial haplotype were significantly associated with growth traits. Polymorphism of 48 of the markers was confirmed in other commercially important aquaculture stocks. Many markers were clustered into genes of metabolic energy production pathways and are suitable candidates for genetic selection. The study demonstrates that RNA-Seq at low sequence coverage of divergent populations is a fast and effective means of identifying SNPs, with allelic imbalances between phenotypes. This technique is suitable for marker development in non-model species lacking complete and well-annotated genome reference sequences.
USDA-ARS?s Scientific Manuscript database
The inheritance of foreground stripe pattern in rind of watermelon fruits [Citrullus lanatus (Thunb.) Matsum. & Nakai] was evaluated and the molecular markers for selecting the JT stripe pattern were developed based on bulked segregant analysis (BSA). Divergence in rind pattern among F2 progeny deri...
Advances and Challenges in Genomic Selection for Disease Resistance.
Poland, Jesse; Rutkoski, Jessica
2016-08-04
Breeding for disease resistance is a central focus of plant breeding programs, as any successful variety must have the complete package of high yield, disease resistance, agronomic performance, and end-use quality. With the need to accelerate the development of improved varieties, genomics-assisted breeding is becoming an important tool in breeding programs. With marker-assisted selection, there has been success in breeding for disease resistance; however, much of this work and research has focused on identifying, mapping, and selecting for major resistance genes that tend to be highly effective but vulnerable to breakdown with rapid changes in pathogen races. In contrast, breeding for minor-gene quantitative resistance tends to produce more durable varieties but is a more challenging breeding objective. As the genetic architecture of resistance shifts from single major R genes to a diffused architecture of many minor genes, the best approach for molecular breeding will shift from marker-assisted selection to genomic selection. Genomics-assisted breeding for quantitative resistance will therefore necessitate whole-genome prediction models and selection methodology as implemented for classical complex traits such as yield. Here, we examine multiple case studies testing whole-genome prediction models and genomic selection for disease resistance. In general, whole-genome models for disease resistance can produce prediction accuracy suitable for application in breeding. These models also largely outperform multiple linear regression as would be applied in marker-assisted selection. With the implementation of genomic selection for yield and other agronomic traits, whole-genome marker profiles will be available for the entire set of breeding lines, enabling genomic selection for disease at no additional direct cost. In this context, the scope of implementing genomics selection for disease resistance, and specifically for quantitative resistance and quarantined pathogens, becomes a tractable and powerful approach in breeding programs.
Lepri, O.; Bassie, L.; Thu-Hang, P.; Christou, P.; Capell, T.
2002-09-01
We used the polyamine biosynthetic pathway and rice as a relevant model to understand the genetic basis of variation in endogenous levels of metabolites and key enzymes involved in the pathway. Wild-type tissues and also tissues containing a commonly used selectable marker gene were employed. We detected a wide variation in levels of arginine decarboxylase activity and in the three polyamines, putrescine, spermidine and spermine, in different tissues and varieties, but this was not dependent on the presence of the selectable marker. A more-extensive profile of enzyme activities (ADC, ODC, SAMDC, DAO and PAO) and polyamine levels in different tissues was generated in two different varieties. Our results indicate that genetic background is important in terms of the basal levels of metabolites and enzyme activity, particularly in situations in which we aim to engineer metabolic pathways that are also encoded by homologous endogenous genes. We did not find any evidence that the presence of a selectable marker in any way influences enzyme activity or metabolite levels.
Association of RGA-SSCP markers with resistance to downy mildew and anthracnose in grapevines.
Tantasawat, P A; Poolsawat, O; Prajongjai, T; Chaowiset, W; Tharapreuksapong, A
2012-07-02
Downy mildew (Plasmopara viticola) and anthracnose (Sphaceloma ampelinum) are two major diseases that severely affect most grapevine (Vitis vinifera) cultivars grown commercially in Thailand. Progress of conventional breeding programs of grapevine for improved resistance to these diseases can be speeded up by selection of molecular markers associated with resistance traits. We evaluated the association between 13 resistance gene analog (RGA)-single-strand conformation polymorphism (SSCP) markers with resistance to downy mildew and anthracnose in 71 segregating progenies of seven cross combinations between susceptible cultivars and resistant lines. F(1) hybrids from each cross were assessed for resistance to downy mildew and anthracnose (isolates Nk4-1 and Rc2-1) under laboratory conditions. Association of resistance traits with RGA-SSCP markers was evaluated using simple linear regression analysis. Three RGA-SSCP markers were found to be significantly correlated with anthracnose resistance, whereas significant correlation with downy mildew resistance was observed for only one RGA-SSCP marker. These results demonstrate the usefulness of RGA-SSCP markers. Four candidate markers with significant associations to resistance to these two major diseases of grapevine were identified. However, these putative associations between markers and resistance need to be verified with larger segregating populations before they can be used for marker-assisted selection.
Geffroy, V; Creusot, F; Falquet, J; Sévignac, M; Adam-Blondon, A F; Bannerot, H; Gepts, P; Dron, M
1998-03-01
Molecular markers offer new opportunities for breeding for disease resistance. Resistance gene pyramiding in a single cultivar, as a strategy for durable resistance, can be facilitated by marker-assisted selection (MAS). A RAPD marker, ROH20(450), linked to the Mesoamerican Co-2 anthracnose resistance gene, was previously transformed into a SCAR marker, SCH20. In the present paper we have further characterized the relevance of the SCH20 SCAR marker in different genetic backgrounds. Since this SCAR marker was found to be useful mainly in the Andean gene pool, we identified a new PCR-based marker (SCAreoli) for indirect scoring of the presence of the Co-2 gene. The SCAreoli SCAR marker is polymorphic in the Mesoamerican as well as in the Andean gene pool and should be useful in MAS. We also report that PvH20, the cloned sequence corresponding to the 450-bp RAPD marker ROH20(450), contains six imperfect leucine-rich repeats, and reveals a family of related sequences in the vicinity of the Co-2 locus. These results are discussed in the context of the recent cloning of some plant resistance genes.
USDA-ARS?s Scientific Manuscript database
Genomic Selection (GS) is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its ef...
Devis, Laura; Martinez-Garcia, Elena; Moiola, Cristian P.; Quiles, Maria Teresa; Arbos, Maria Antonia; Stirbat, Tomita Vasilica; Brochard-Wyart, Françoise; García, Ángel; Alonso-Alconada, Lorena; Abal, Miguel; Diaz-Feijoo, Berta; Thomas, William; Dufour, Sylvie; Mancebo, Gemma; Alameda, Francesc
2018-01-01
Endometrial cancer (EC) is the sixth deadliest cancer in women. The depth of myometrial invasion is one of the most important prognostic factors, being directly associated with tumor recurrence and mortality. In this study, ALCAM, a previously described marker of EC recurrence, was studied by immunohistochemistry at the superficial and the invasive tumor areas from 116 EC patients with different degree of myometrial invasion and related to a set of relevant epithelial and mesenchymal markers. ALCAM expression presented a heterogeneous functionality depending on its localization, it correlated with epithelial markers (E-cadherin/β-catenin) at the superficial area, and with mesenchymal markers at the invasive front (COX-2, SNAIL, ETV5, and MMP-9). At the invasive front, ALCAM-negativity was an independent marker of myometrial invasion. This negativity, together with an increase of soluble ALCAM in uterine aspirates from patients with an invasive EC, and its positive correlation with MMP-9 levels, suggested that ALCAM shedding by MMP-9 occurs at the invasive front. In vivo and in vitro models of invasive EC were generated by ETV5-overexpression. In those, we demonstrated that ALCAM shedding was related to a more invasive pattern and that full-ALCAM recovery reverted most of the ETV5-cells mesenchymal abilities, partially through a p-ERK dependent-manner. PMID:29682175
USDA-ARS?s Scientific Manuscript database
Genetic marker effects and type of inheritance are estimated with poor precision when minor marker allele frequencies are low. An Angus population was subjected to marker assisted selection for multiple years to equalize CAPN1 haplotypes, CAST, and GHR genetic marker frequencies. The objective was t...
21 CFR 500.86 - Marker residue and target tissue.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Marker residue and target tissue. 500.86 Section...-Producing Animals § 500.86 Marker residue and target tissue. (a) For each edible tissue, the sponsor shall...) From these data, FDA will select a target tissue and a marker residue and designate the concentration...
21 CFR 500.86 - Marker residue and target tissue.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Marker residue and target tissue. 500.86 Section...-Producing Animals § 500.86 Marker residue and target tissue. (a) For each edible tissue, the sponsor shall...) From these data, FDA will select a target tissue and a marker residue and designate the concentration...
A framework linkage map of perennial ryegrass based on SSR markers
G.P. Gill; P.L. Wilcox; D.J. Whittaker; R.A. Winz; P. Bickerstaff; Craig E. Echt; J. Kent; M.O. Humphreys; K.M. Elborough; R.C. Gardner
2006-01-01
A moderate-density linkage map for Lolium perenne L. has been constructed based on 376 simple sequence repeat (SSR) markers. Approximately one third ( 124) of the SSR markers were developed from GeneThresher libraries that preferentially select genomic DNA clones from the gene-rich unmethylated portion of the genome. The remaining SSR marker loci...
Dong, Lin-Lin; Chen, Zhong-Jian; Wang, Yong; Wei, Fu-Gang; Zhang, Lian-Juan; Xu, Jiang; Wei, Guang-Fei; Wang, Rui; Yang, Juan; Liu, Wei-Lin; Li, Xi-Wen; Yu, Yu-Qi; Chen, Shi-Lin
2017-01-01
DNA marker-assisted selection of medicinal plants is based on the DNA polymorphism, selects the DNA sequences related to the phenotypes such as high yields, superior quality, stress-resistance and so on according to the technologies of molecular hybridization, polymerase chain reaction and high-throughput sequencing, and assists the breeding of new cultivars. This study bred the first disease-resistant cultivar of notoginseng "Miaoxiang Kangqi 1" using the technology of DNA marker-assisted selection of medicinal plants and systematic breeding. The disease-resistant cultivar of notoginseng contained 12 special SNPs based on the analysis of Restriction-site Associated DNA Sequencing (RAD-Seq). Among the SNP (record_519688) was related to the root rot-resistant characteristics, which indicated this SNP could serve as genetic markers of disease-resistant cultivars and assist the systematic breeding. Compared to the conventional cultivated cultivars, the incidence rate of root-rot and rust-rot in notoginseng seedlings decreased by 83.6% and 71.8%, respectively. The incidence rate of root-rot respectively declined by 43.6% and 62.9% in notoginseng cultivation for 2 and 3 years compared with those of the conventional cultivated cultivars. Additionally, the potential disease-resistant groups were screened based on the relative SNP, and this model enlarged the target groups and advanced the breeding efficiency. DNA marker-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry. Copyright© by the Chinese Pharmaceutical Association.
Zhu, Huaping; Liu, Zhigang; Lu, Maixin; Gao, Fengying; Ke, Xiaoli; Ma, Dongmei; Huang, Zhanghan; Cao, Jianmeng; Wang, Miao
2016-06-01
In this study, primer pairs of 15 microsatellite markers associated with sex determination of tilapia were selected and amplified in Wami tilapia, Oreochromis urolepis hornorum. While one marker, UNH168, on linkage group 3 (LG3) was associated (P <0.001) with the phenotypic sex in the experimental population, nine genotypes were detected in both sexes. Only 99-bp allele was detected in the female samples, while 141, 149 and 157-bp alleles were present in both male and female samples. UNH168 was localized by fluorescence in situ hybridization (FISH) on the long arm of the largest tilapia chromosome pair (chromosome 1, equivalent to LG3). This sex-linked microsatellite marker could potentially be used for marker-assisted selection in tilapia breeding programmes to produce monosex male tilapia.
Tian, Ying; Arai, Eri; Gotoh, Masahiro; Komiyama, Motokiyo; Fujimoto, Hiroyuki; Kanai, Yae
2014-10-20
The CpG island methylator phenotype (CIMP) of clear cell renal cell carcinomas (ccRCCs) is characterized by accumulation of DNA methylation at CpG islands and poorer patient outcome. The aim of this study was to establish criteria for prognostication of patients with ccRCCs using the ccRCC-specific CIMP marker genes. DNA methylation levels at 299 CpG sites in the 14 CIMP marker genes were evaluated quantitatively in tissue specimens of 88 CIMP-negative and 14 CIMP-positive ccRCCs in a learning cohort using the MassARRAY system. An additional 100 ccRCCs were also analyzed as a validation cohort. Receiver operating characteristic curve analysis showed that area under the curve values for the 23 CpG units including the 32 CpG sites in the 7 CIMP-marker genes, i.e. FAM150A, ZNF540, ZNF671, ZNF154, PRAC, TRH and SLC13A5, for discrimination of CIMP-positive from CIMP-negative ccRCCs were larger than 0.95. Criteria combining the 23 CpG units discriminated CIMP-positive from CIMP-negative ccRCCs with 100% sensitivity and specificity in the learning cohort. Cancer-free and overall survival rates of patients with CIMP-positive ccRCCs diagnosed using the criteria combining the 23 CpG units in a validation cohort were significantly lower than those of patients with CIMP-negative ccRCCs (P = 1.41 × 10-5 and 2.43 × 10-13, respectively). Patients with CIMP-positive ccRCCs in the validation cohort had a higher likelihood of disease-related death (hazard ratio, 75.8; 95% confidence interval, 7.81 to 735; P = 1.89 × 10-4) than those with CIMP-negative ccRCCs. The established criteria are able to reproducibly diagnose CIMP-positive ccRCCs and may be useful for personalized medicine for patients with ccRCCs.
Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun
2016-06-04
Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to "Gopoong" and "K-1" were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information.
Gans, Sarah L; Atema, Jasper J; van Dieren, Susan; Groot Koerkamp, Bas; Boermeester, Marja A
2015-07-01
Infectious complications occur frequently after major abdominal surgery and have a major influence on patient outcome and hospital costs. A marker that can rule out postoperative infectious complications (PICs) could aid patient selection for safe and early hospital discharge. C-reactive protein (CRP) is a widely available, fast, and cheap marker that might be of value in detecting PIC. Present meta-analysis evaluates the diagnostic value of CRP to rule out PIC following major abdominal surgery, aiding patient selection for early discharge. A systematic literature search of Medline, PubMed, and Cochrane was performed identifying all prospective studies evaluating the diagnostic value of CRP after abdominal surgery. Meta-analysis was performed according to the PRISMA statement. Twenty-two studies were included for qualitative analysis of which 16 studies were eligible for meta-analysis, representing 2215 patients. Most studies analyzed the value of CRP in colorectal surgery (eight studies). The pooled negative predictive value (NPV) improved each day after surgery up to 90% at postoperative day (POD) 3 for a pooled CRP cutoff of 159 mg/L (range 92-200). Maximum predictive values for PICs were reached on POD 5 for a pooled CRP cutoff of 114 mg/L (range 48-150): a pooled sensitivity of 86% (95% confidence interval (CI) 79-91%), specificity of 86% (95% CI 75-92%), and a positive predictive value of 64% (95% CI 49-77%). The pooled sensitivity and specificity were significantly higher on POD 5 than on other PODs (p < 0.001). Infectious complications after major abdominal surgery are very unlikely in patients with a CRP below 159 mg/L on POD 3. This can aid patient selection for safe and early hospital discharge and prevent overuse of imaging.
[A Method for Selecting Self-Adoptive Chromaticity of the Projected Markers].
Zhao, Shou-bo; Zhang, Fu-min; Qu, Xing-hua; Zheng, Shi-wei; Chen, Zhe
2015-04-01
The authors designed a self-adaptive projection system which is composed of color camera, projector and PC. In detail, digital micro-mirror device (DMD) as a spatial light modulator for the projector was introduced in the optical path to modulate the illuminant spectrum based on red, green and blue light emitting diodes (LED). However, the color visibility of active markers is affected by the screen which has unknown reflective spectrum as well. Here active markers are projected spot array. And chromaticity feature of markers is sometimes submerged in similar spectral screen. In order to enhance the color visibility of active markers relative to screen, a method for selecting self-adaptive chromaticity of the projected markers in 3D scanning metrology is described. Color camera with 3 channels limits the accuracy of device characterization. For achieving interconversion of device-independent color space and device-dependent color space, high-dimensional linear model of reflective spectrum was built. Prior training samples provide additional constraints to yield high-dimensional linear model with more than three degrees of freedom. Meanwhile, spectral power distribution of ambient light was estimated. Subsequently, markers' chromaticity in CIE color spaces was selected via maximization principle of Euclidean distance. The setting values of RGB were easily estimated via inverse transform. Finally, we implemented a typical experiment to show the performance of the proposed approach. An 24 Munsell Color Checker was used as projective screen. Color difference in the chromaticity coordinates between the active marker and the color patch was utilized to evaluate the color visibility of active markers relative to the screen. The result comparison between self-adaptive projection system and traditional diode-laser light projector was listed and discussed to highlight advantage of our proposed method.
Zhang, Hong; Zhang, Lu; Wang, Changyou; Wang, Yajuan; Zhou, Xinli; Lv, Shikai; Liu, Xinlun; Kang, Zhensheng; Ji, Wanquan
2016-02-01
YrSM139-1B maybe a new gene for effective resistance to stripe rust and useful flanking markers for marker-assisted selection were developed. Stripe rust, caused by Puccinia striiformis f. sp. tritici, is an important foliar disease of wheat. Two dominant stripe rust resistant genes YrSM139-1B and YrSM139-2D were pyramided in bread wheat cultivar Shaanmai 139; one from wild emmer and the other from Thinopyrum intermedium. Three near-isogenic F7:8 line pairs (contrasting RILs), N122-1013R/S, N122-185R/S, and N122-1812R/S, independently derived from different F2 plants and differing at the YrSM139-1B locus were generated from the cross Shaanmai 139 × Hu 901-19 through marker-assisted selection. A large F2:3 population from cross N122-1013R × N122-1013S tested for stripe rust response and subjected to analysis with markers in the 1BS10-0.5 bin region using SSR expressed sequence tags (EST) and site-specific sequence markers developed from the 90 K Illumina iSelect SNP array. Five EST-STS markers and four allele-specific PCR markers were mapped to the YrSM139-1B region. The 30.5 cM genetic map for YrSM139-1B consisted of nine markers, two of which were closer to YrSM139-1B than Xgwm273, which was used in producing the contrasting RIL pairs. Race response data and allelism tests showed that YrSM139-1B is different from Yr10, Yr15, and Yr24/26/CH42.
Damsgaard, Camilla T.; Eidner, Maj B.; Stark, Ken D.; Hjorth, Mads F.; Sjödin, Anders; Andersen, Malene R.; Andersen, Rikke; Tetens, Inge; Astrup, Arne; Michaelsen, Kim F.; Lauritzen, Lotte
2014-01-01
n-3 long-chain polyunsaturated fatty acids improve cardiovascular risk markers in adults. These effects may differ between eicosapentaenoic acid (EPA, 20∶5n-3) and docosahexaenoic acid (DHA, 22∶6n-3), but we lack evidence in children. Using baseline data from the OPUS School Meal Study we 1) investigated associations between EPA and DHA in whole blood and early cardiometabolic risk markers in 713 children aged 8–11 years and 2) explored potential mediation through waist circumference and physical activity and potential dietary confounding. We collected data on parental education, pubertal stage, 7-day dietary records, physical activity by accelerometry and measured anthropometry, blood pressure, and heart rate. Blood samples were analyzed for whole blood fatty acid composition, cholesterols, triacylglycerol, insulin resistance by the homeostatic model of assessment (HOMA-IR), and inflammatory markers. Whole blood EPA was associated with a 2.7 mmHg (95% CI 0.4; 5.1) higher diastolic blood pressure per weight% EPA, but only in boys. Heart rate was negatively associated with both EPA and DHA status (P = 0.02 and P = 0.002, respectively). Whole blood EPA was negatively associated with triacylglycerol (P = 0.003) and positively with total cholesterol, low density and high density lipoprotein (HDL) cholesterol and HDL:triacylglycerol (all P<0.01) whereas DHA was negatively associated with insulin and HOMA-IR (P = 0.003) and tended to be negatively associated with a metabolic syndrome-score (P = 0.05). Adjustment for waist circumference and physical activity did not change the associations. The association between DHA and HOMA-IR was attenuated but remained after adjustment for fiber intake and none of the other associations were confounded by dietary fat, protein, fiber or energy intake. This study showed that EPA status was negatively associated with triacylglycerol and positively with cholesterols whereas DHA was negatively associated with insulin resistance, and both were inversely associated with heart rate in children. The sex-specific associations with blood pressure confirm our previous findings and warrant further investigation. PMID:25330302
Shan, Naing Lin; Wahler, Joseph; Lee, Hong Jin; Bak, Min Ji; Gupta, Soumyasri Das; Maehr, Hubert; Suh, Nanjoo
2017-10-01
Triple-negative breast cancer is one of the least responsive breast cancer subtypes to available targeted therapies due to the absence of hormonal receptors, aggressive phenotypes, and the high rate of relapse. Early breast cancer prevention may therefore play an important role in delaying the progression of triple-negative breast cancer. Cancer stem cells are a subset of cancer cells that are thought to be responsible for tumor progression, treatment resistance, and metastasis. We have previously shown that vitamin D compounds, including a Gemini vitamin D analog BXL0124, suppress progression of ductal carcinoma in situ in vivo and inhibit cancer stem-like cells in MCF10DCIS mammosphere cultures. In the present study, the effects of vitamin D compounds in regulating breast cancer stem-like cells and differentiation in triple-negative breast cancer were assessed. Mammosphere cultures, which enriches for breast cancer cells with stem-like properties, were used to assess the effects of 1α,25(OH) 2 D 3 and BXL0124 on cancer stem cell markers in the triple-negative breast cancer cell line, SUM159. Vitamin D compounds significantly reduced the mammosphere forming efficiency in primary, secondary and tertiary passages of mammospheres compared to control groups. Key markers of cancer stem-like phenotype and pluripotency were analyzed in mammospheres treated with 1α,25(OH) 2 D 3 and BXL0124. As a result, OCT4, CD44 and LAMA5 levels were decreased. The vitamin D compounds also down-regulated the Notch signaling molecules, Notch1, Notch2, Notch3, JAG1, JAG2, HES1 and NFκB, which are involved in breast cancer stem cell maintenance. In addition, the vitamin D compounds up-regulated myoepithelial differentiating markers, cytokeratin 14 and smooth muscle actin, and down-regulated the luminal marker, cytokeratin 18. Cytokeratin 5, a biomarker associated with basal-like breast cancer, was found to be significantly down-regulated by the vitamin D compounds. These results suggest that vitamin D compounds may serve as potential preventive agents to inhibit triple negative breast cancer by regulating cancer stem cells and differentiation. Copyright © 2016 Elsevier Ltd. All rights reserved.
Duris, Joseph W.; Reif, Andrew G.; Olson, Leif E.; Johnson, Heather E.
2011-01-01
The City of Wilmington, Delaware, is in the downstream part of the Brandywine Creek Basin, on the main stem of Brandywine Creek. Wilmington uses this stream, which drains a mixed-land-use area upstream, for its main drinking-water supply. Because the stream is used for drinking water, Wilmington is in need of information about the occurrence and distribution of specific fecally derived pathogenic bacteria (disease-causing bacteria) and their relations to commonly measured fecal-indicator bacteria (FIB), as well as information regarding the potential sources of the fecal pollution and pathogens in the basin. This study focused on five routinely sampled sites within the basin, one each on the West Branch and the East Branch of Brandywine Creek and at three on the main stem below the confluence of the West and East Branches. These sites were sampled monthly for 1 year. Targeted event samples were collected on two occasions during high flow and two occasions during normal flow. On the basis of this study, high flows in the Brandywine Creek Basin were related to increases in FIB densities, and in the frequency of selected pathogen and source markers, in the West Branch and main stem of Brandywine Creek, but not in the East Branch. Water exceeding the moderate fullbody-contact single-sample recreational water-quality criteria (RWQC) for Escherichia coli (E. coli) was more likely to contain selected markers for pathogenic E. coli (eaeA,stx1, and rfbO157 gene markers) and bovine fecal sources (E. hirae and LTIIa gene markers), whereas samples exceeding the enterococci RWQC were more likely to contain the same pathogenic markers but also were more likely to carry a marker indicative of human source (esp gene marker). On four sample dates, during high flow between October and March, the West Branch was the only observed potential contributor of selected pathogen and bovine source markers to the main stem of Brandywine Creek. Indeed, the stx2 marker, which indicates a highly virulent type of pathogenic E. coli, was found only in the West Branch and main stem at high flow but was not found in the East Branch under similar conditions. However, it must be noted that throughout the entire year of sampling there were occasions, during both high and normal flows, when both the East and West Branches were potential contributors of pathogen and microbial-source tracking markers to the main stem. Therefore, this study indicates that under selected conditions (high flow, October through March), West Branch Brandywine Creek Basin was the most likely source of elevated FIB densities in the main stem. These elevated densities are associated with more frequent detection of selected pathogenic E. coli markers (rfbO157 stx1) and are associated with MST markers of bovine source. However, during other times of the year, both the West Branch and East Branch Basins are acting as potential sources of FIB and fecally derived pathogens.
A 48 SNP set for grapevine cultivar identification
2011-01-01
Background Rapid and consistent genotyping is an important requirement for cultivar identification in many crop species. Among them grapevine cultivars have been the subject of multiple studies given the large number of synonyms and homonyms generated during many centuries of vegetative multiplication and exchange. Simple sequence repeat (SSR) markers have been preferred until now because of their high level of polymorphism, their codominant nature and their high profile repeatability. However, the rapid application of partial or complete genome sequencing approaches is identifying thousands of single nucleotide polymorphisms (SNP) that can be very useful for such purposes. Although SNP markers are bi-allelic, and therefore not as polymorphic as microsatellites, the high number of loci that can be multiplexed and the possibilities of automation as well as their highly repeatable results under any analytical procedure make them the future markers of choice for any type of genetic identification. Results We analyzed over 300 SNP in the genome of grapevine using a re-sequencing strategy in a selection of 11 genotypes. Among the identified polymorphisms, we selected 48 SNP spread across all grapevine chromosomes with allele frequencies balanced enough as to provide sufficient information content for genetic identification in grapevine allowing for good genotyping success rate. Marker stability was tested in repeated analyses of a selected group of cultivars obtained worldwide to demonstrate their usefulness in genetic identification. Conclusions We have selected a set of 48 stable SNP markers with a high discrimination power and a uniform genome distribution (2-3 markers/chromosome), which is proposed as a standard set for grapevine (Vitis vinifera L.) genotyping. Any previous problems derived from microsatellite allele confusion between labs or the need to run reference cultivars to identify allele sizes disappear using this type of marker. Furthermore, because SNP markers are bi-allelic, allele identification and genotype naming are extremely simple and genotypes obtained with different equipments and by different laboratories are always fully comparable. PMID:22060012
Small serine recombination systems ParA-MRS and CinH-RS2 perform precise excision of plastid DNA
USDA-ARS?s Scientific Manuscript database
Selectable marker genes (SMGs) are necessary for selection of transgenic plants. However, once stable transformants have been identified, the marker gene is no longer needed. In this study, we demonstrate the use of the small serine recombination systems, ParA-MRS and CinH-RS2, to precisely excise ...
USDA-ARS?s Scientific Manuscript database
Generation Inter-Cross (MAGIC) and Marker-Assisted Recurrent Selection (MARS) have been proposed and used in many crops to dissect complex traits or QTL. MAGIC allows for dissecting genomic structure, and for improving breeding populations by integrating multiple alleles from different parents. MAR...
Accuracy and training population design for genomic selection in elite north american oats
USDA-ARS?s Scientific Manuscript database
Genomic selection (GS) is a method to estimate the breeding values of individuals by using markers throughout the genome. We evaluated the accuracies of GS using data from five traits on 446 oat lines genotyped with 1005 Diversity Array Technology (DArT) markers and two GS methods (RR-BLUP and Bayes...
Lima, L S; Gramacho, K P; Carels, N; Novais, R; Gaiotto, F A; Lopes, U V; Gesteira, A S; Zaidan, H A; Cascardo, J C M; Pires, J L; Micheli, F
2009-07-14
In order to increase the efficiency of cacao tree resistance to witches' broom disease, which is caused by Moniliophthora perniciosa (Tricholomataceae), we looked for molecular markers that could help in the selection of resistant cacao genotypes. Among the different markers useful for developing marker-assisted selection, single nucleotide polymorphisms (SNPs) constitute the most common type of sequence difference between alleles and can be easily detected by in silico analysis from expressed sequence tag libraries. We report the first detection and analysis of SNPs from cacao-M. perniciosa interaction expressed sequence tags, using bioinformatics. Selection based on analysis of these SNPs should be useful for developing cacao varieties resistant to this devastating disease.
NASA Astrophysics Data System (ADS)
Klinger, E.; Sargsyan, A.; Leroy, C.; Sarkisyan, D.
2017-10-01
We studied selective reflection (SR) of laser radiation from a window of a nanocell with thickness L λ 1,2/2 filled with Rb and Cs atoms, where λ 1 = 780 nm and λ 2 = 852 nm are the wavelengths resonant with the D 2 laser lines for Rb and Cs, respectively. It is demonstrated that the negative derivative of the SR signal profile for L > λ/2 changes to the positive one for L < λ/2. It is shown that the real-time formation of the SR signal profile derivative (SRD) with the spectral width 30-40 MHz and located at the atomic transition is, in particular, a convenient frequency marker of D 2 transitions in Rb and Cs. The amplitudes of SRD signals are proportional to the atomic transition probabilities. A comparison with the known saturated absorption (SA) method demonstrated a number of advantages, such as the absence of cross-over resonances in the SRD spectrum, the simplicity of realization, a low required power, etc. An SRD frequency marker also operates in the presence of the Ne buffer gas at a pressure of 6 Torr, which allowed us to determine the Ne-Rb collisional broadening, whereas the SA method is already inapplicable at buffer gas pressures above 0.1 Torr. The realization simplicity makes the SRD method a convenient tool for atomic spectroscopy. Our theoretical model well describes the SRD signal.
Lee, Sang Mi; Kim, Ji Woo; Jeong, Young-Hee; Kim, Se Eun; Kim, Yeong Ji; Moon, Seung Ju; Lee, Ji-Hye; Kim, Keun-Jung; Kim, Min-Kyu; Kang, Man-Jong
2014-11-01
Transgenic animals have become important tools for the production of therapeutic proteins in the domestic animal. Production efficiencies of transgenic animals by conventional methods as microinjection and retrovirus vector methods are low, and the foreign gene expression levels are also low because of their random integration in the host genome. In this study, we investigated the homologous recombination on the porcine β-casein gene locus using a knock-in vector for the β-casein gene locus. We developed the knock-in vector on the porcine β-casein gene locus and isolated knock-in fibroblast for nuclear transfer. The knock-in vector consisted of the neomycin resistance gene (neo) as a positive selectable marker gene, diphtheria toxin-A gene as negative selection marker, and 5' arm and 3' arm from the porcine β-casein gene. The secretion of enhanced green fluorescent protein (EGFP) was more easily detected in the cell culture media than it was by western blot analysis of cell extract of the HC11 mouse mammary epithelial cells transfected with EGFP knock-in vector. These results indicated that a knock-in system using β-casein gene induced high expression of transgene by the gene regulatory sequence of endogenous β-casein gene. These fibroblasts may be used to produce transgenic pigs for the production of therapeutic proteins via the mammary glands.
Lee, Sang Mi; Kim, Ji Woo; Jeong, Young-Hee; Kim, Se Eun; Kim, Yeong Ji; Moon, Seung Ju; Lee, Ji-Hye; Kim, Keun-Jung; Kim, Min-Kyu; Kang, Man-Jong
2014-01-01
Transgenic animals have become important tools for the production of therapeutic proteins in the domestic animal. Production efficiencies of transgenic animals by conventional methods as microinjection and retrovirus vector methods are low, and the foreign gene expression levels are also low because of their random integration in the host genome. In this study, we investigated the homologous recombination on the porcine β-casein gene locus using a knock-in vector for the β-casein gene locus. We developed the knock-in vector on the porcine β-casein gene locus and isolated knock-in fibroblast for nuclear transfer. The knock-in vector consisted of the neomycin resistance gene (neo) as a positive selectable marker gene, diphtheria toxin-A gene as negative selection marker, and 5′ arm and 3′ arm from the porcine β-casein gene. The secretion of enhanced green fluorescent protein (EGFP) was more easily detected in the cell culture media than it was by western blot analysis of cell extract of the HC11 mouse mammary epithelial cells transfected with EGFP knock-in vector. These results indicated that a knock-in system using β-casein gene induced high expression of transgene by the gene regulatory sequence of endogenous β-casein gene. These fibroblasts may be used to produce transgenic pigs for the production of therapeutic proteins via the mammary glands. PMID:25358326
Tandoi, Francesco; Caviglia, Gian Paolo; Pittaluga, Fabrizia; Abate, Maria Lorena; Smedile, Antonina; Romagnoli, Renato; Salizzoni, Mauro
2014-11-01
Occult hepatitis B virus infection is defined as detectable HBV-DNA in liver of HBsAg-negative individuals, with or without detectable serum HBV-DNA. In deceased liver donors, results of tissue analysis cannot be obtained prior to allocation for liver transplantation. we investigated prevalence and predictability of occult hepatitis B using blood markers of viral exposure/infection in deceased liver donors. In 50 consecutive HBsAg-negative/anti-HBc-positive and 20 age-matched HBsAg-negative/anti-HBc-negative donors, a nested-PCR assay was employed in liver biopsies for diagnosis of occult hepatitis B according to Taormina criteria. All donors were characterized for plasma HBV-DNA and serum anti-HBs/anti-HBe. In liver tissue, occult hepatitis B was present in 30/50 anti-HBc-positive (60%) and in 0/20 anti-HBc-negative donors (p<0.0001). All anti-HBc-positive donors with detectable HBV-DNA in plasma (n=5) or anti-HBs>1,000 mIU/mL (n=5) eventually showed occult infection, i.e, 10/30 occult hepatitis B-positive donors which could have been identified prior to transplantation. In the remaining 40 anti-HBc-positive donors, probability of occult infection was 62% for anti-HBe-positive and/or anti-HBs ≥ 58 mIU/mL; 29% for anti-HBe-negative and anti-HBs<58 mIU/mL. In deceased donors, combining anti-HBc with other blood markers of hepatitis B exposure/infection allows to predict occult hepatitis B with certainty and speed in one third of cases. These findings might help refine the allocation of livers from anti-HBc-positive donors. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Novel Adult Stem Cells for Peripheral Nerve Regeneration
2012-09-01
were also positive for MSC surface marker CD29 and CD44 (Fig. 1F-G). However, CD29 and CD44 are also expressed in SMCs, so we will not use these non...tubulin. In addition, MVSCs were negative for perivascular MSC marker CD146 (Fig. 1H) and SMC progenitor marker Sca-1 (Fig. 1I). MVSCs were also...University of California, Berkeley, California 94720, USA. 2 UC Berkeley-UCSF Graduate Program in Bioengineering, Berkeley, California 94720, USA. 3
Molad, Jeremy; Kliper, Efrat; Korczyn, Amos D; Ben Assayag, Einor; Ben Bashat, Dafna; Shenhar-Tsarfaty, Shani; Aizenstein, Orna; Shopin, Ludmila; Bornstein, Natan M; Auriel, Eitan
2017-01-01
White matter hyperintensities (WMH) were shown to predict cognitive decline following stroke or transient ischemic attack (TIA). However, WMH are only one among other radiological markers of cerebral small vessel disease (SVD). The aim of this study was to determine whether adding other SVD markers to WMH improves prediction of post-stroke cognitive performances. Consecutive first-ever stroke or TIA patients (n = 266) from the Tel Aviv Acute Brain Stroke Cohort (TABASCO) study were enrolled. MRI scans were performed within seven days of stroke onset. We evaluated the relationship between cognitive performances one year following stroke, and previously suggested total SVD burden score including WMH, lacunes, cerebral microbleeds (CMB), and perivascular spaces (PVS). Significant negative associations were found between WMH and cognition (p < 0.05). Adding other SVD markers (lacunes, CMB, PVS) to WMH did not improve predication of post-stroke cognitive performances. Negative correlations between SVD burden score and cognitive scores were observed for global cognitive, memory, and visual spatial scores (all p < 0.05). However, following an adjustment for confounders, no associations remained significant. WMH score was associated with poor post-stroke cognitive performance. Adding other SVD markers or SVD burden score, however, did not improve prediction.
Maximization of Markers Linked in Coupling for Tetraploid Potatoes via Monoparental Haploids
Bartkiewicz, Annette M.; Chilla, Friederike; Terefe-Ayana, Diro; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhard; Linde, Marcus; Debener, Thomas
2018-01-01
Haploid potato populations derived from a single tetraploid donor constitute an efficient strategy to analyze markers segregating from a single donor genotype. Analysis of marker segregation in populations derived from crosses between polysomic tetraploids is complicated by a maximum of eight segregating alleles, multiple dosages of the markers and problems related to linkage analysis of marker segregation in repulsion. Here, we present data on two monoparental haploid populations generated by prickle pollination of two tetraploid cultivars with Solanum phureja and genotyped with the 12.8 k SolCAP single nucleotide polymorphism (SNP) array. We show that in a population of monoparental haploids, the number of biallelic SNP markers segregating in linkage to loci from the tetraploid donor genotype is much larger than in putative crosses of this genotype to a diverse selection of 125 tetraploid cultivars. Although this strategy is more laborious than conventional breeding, the generation of haploid progeny for efficient marker analysis is straightforward if morphological markers and flow cytometry are utilized to select true haploid progeny. The level of introgressed fragments from S. phureja, the haploid inducer, is very low, supporting its suitability for genetic analysis. Mapping with single-dose markers allowed the analysis of quantitative trait loci (QTL) for four phenotypic traits. PMID:29868076
[Production of marker-free plants expressing the gene of the hepatitis B virus surface antigen].
Rukavtsova, E B; Gaiazova, A R; Chebotareva, E N; Bur'ianova, Ia I
2009-08-01
The pBM plasmid, carrying the gene of hepatitis B virus surface antigen (HBsAg) and free of any selection markers of antibiotic or herbicide resistance, was constructed for genetic transformation of plants. A method for screening transformed plant seedlings on nonselective media was developed. Enzyme immunoassay was used for selecting transgenic plants with HBsAg gene among the produced regenerants; this method provides for a high sensitivity detection of HBsAg in plant extracts. Tobacco and tomato transgenic lines synthesizing this antigen at a level of 0.01-0.05% of the total soluble protein were obtained. The achieved level of HBsAg synthesis is sufficient for preclinical trials of the produced plants as a new generation safe edible vaccine. The developed method for selecting transformants can be used for producing safe plants free of selection markers.
Li, Y. H.; Chu, H. P.; Jiang, Y. N.; Lin, C. Y.; Li, S. H.; Li, K. T.; Weng, G. J.; Cheng, C. C.; Lu, D. J.; Ju, Y. T.
2014-01-01
The Lanyu is a miniature pig breed indigenous to Lanyu Island, Taiwan. It is distantly related to Asian and European pig breeds. It has been inbred to generate two breeds and crossed with Landrace and Duroc to produce two hybrids for laboratory use. Selecting sets of informative genetic markers to track the genetic qualities of laboratory animals and stud stock is an important function of genetic databases. For more than two decades, Lanyu derived breeds of common ancestry and crossbreeds have been used to examine the effectiveness of genetic marker selection and optimal approaches for individual assignment. In this paper, these pigs and the following breeds: Berkshire, Duroc, Landrace and Yorkshire, Meishan and Taoyuan, TLRI Black Pig No. 1, and Kaohsiung Animal Propagation Station Black pig are studied to build a genetic reference database. Nineteen microsatellite markers (loci) provide information on genetic variation and differentiation among studied breeds. High differentiation index (FST) and Cavalli-Sforza chord distances give genetic differentiation among breeds, including Lanyu’s inbred populations. Inbreeding values (FIS) show that Lanyu and its derived inbred breeds have significant loss of heterozygosity. Individual assignment testing of 352 animals was done with different numbers of microsatellite markers in this study. The testing assigned 99% of the animals successfully into their correct reference populations based on 9 to 14 markers ranking D-scores, allelic number, expected heterozygosity (HE) or FST, respectively. All miss-assigned individuals came from close lineage Lanyu breeds. To improve individual assignment among close lineage breeds, microsatellite markers selected from Lanyu populations with high polymorphic, heterozygosity, FST and D-scores were used. Only 6 to 8 markers ranking HE, FST or allelic number were required to obtain 99% assignment accuracy. This result suggests empirical examination of assignment-error rates is required if discernible levels of co-ancestry exist. In the reference group, optimum assignment accuracy was achievable achieved through a combination of different markers by ranking the heterozygosity, FST and allelic number of close lineage populations. PMID:25049996
Shahera, Umme; Munshi, Saifullah; Jahan, Munira; Nessa, Afzalun; Alam, Shahinul; Tabassum, Shahina
2016-01-01
Elucidating differences in gene expression may be useful in understanding the molecular pathogenesis and for developing specific markers for the outcome of hepatitis B virus (HBV) infection. In the present study, expressions of host gene interferon gamma-inducible protein (IP-10), p53, and Foxp3 were studied in hepatocytes of patients with chronic HBV infection to determine a possible link between selected host gene expression and the outcome of HBV infection. The study was conducted in 60 patients with chronic HBV infection and they were divided into four groups: HBV-positive cirrhosis (n = 15), HBV-negative cirrhosis (n = 15), HBV-positive hepatocellular carcinoma (HCC) (n = 15) and HBV-negative HCC (n = 15). Total messenger ribonucleic acid (mRNA) extraction was done followed by complementary deoxyribonucleic acid (cDNA) synthesis, and finally gene expression was performed using real-time polymerase chain reaction (PCR) technique. IP-10 and p53 gene expressions were lower in HBV-positive cirrhosis, and Foxp3 gene expression was upregulated in HBV-positive cirrhosis in comparison to HBV-negative cirrhosis. The expressions of all the three genes were upregulated among HBV-positive HCC in comparison to HBV-negative HCC. The expression of IP-10, p53, and Foxp3 genes was upregulated in HBV-positive HCC in comparison to HBV-positive cirrhosis. This study indicates that there are variations in the expression of the selected genes among cirrhosis and HCC patients with or without HBV. All the three selected genes were more or less upregulated in HBV-positive HCC patients, but only Foxp3 expression was upregulated in HBV-positive cirrhosis. These three particular genes may have a role in the molecular pathogenesis and clinical outcome of HBV-positive cirrhosis and HCC patients. These aspects need further evaluation by studies with larger numbers of cirrhosis and HCC patients. Shahera U, Munshi S, Jahan M, Nessa A, Alam S, Tabassum S. IP-10, p53, and Foxp3 Expression in Hepatocytes of Chronic Hepatitis B Patients with Cirrhosis and Hepatocellular Carcinoma. Euroasian J Hepato-Gastroenterol 2016;6(2):149-153.
Krak, Karol; Alvarez, Inés; Caklová, Petra; Costa, Andrea; Chrtek, Jindrich; Fehrer, Judith
2012-02-01
The development of three low-copy nuclear markers for low taxonomic level phylogenies in Asteraceae with emphasis on the subtribe Hieraciinae is reported. Marker candidates were selected by comparing a Lactuca complementary DNA (cDNA) library with public DNA sequence databases. Interspecific variation and phylogenetic signal of the selected genes were investigated for diploid taxa from the subtribe Hieraciinae and compared to a reference phylogeny. Their ability to cross-amplify was assessed for other Asteraceae tribes. All three markers had higher variation (2.1-4.5 times) than the internal transcribed spacer (ITS) in Hieraciinae. Cross-amplification was successful in at least seven other tribes of the Asteraceae. Only three cases indicating the presence of paralogs or pseudogenes were detected. The results demonstrate the potential of these markers for phylogeny reconstruction in the Hieraciinae as well as in other Asteraceae tribes, especially for very closely related species.
Salivary biomarkers of neural hypervigilance in trauma-exposed women.
Yoon, Seungyeon A; Weierich, Mariann R
2016-01-01
More than half of all adults will be exposed to a traumatic event at some point in their lives, yet we do not yet have reliable biomarkers to help predict who experiences trauma-related symptoms in response to exposure. We tested the utility of salivary cortisol and salivary alpha amylase as markers of (1) neural reactivity to negative affective information and (2) neural hypervigilance in the absence of threat. 20 women (mean age 23.6 +/- 5.8 years) with a history of trauma exposure. Salivary cortisol and alpha amylase reactivity were measured in response to a trauma reminder during a clinical interview. Neural reactivity to novel and familiar affective scenes was measured in a later session using functional magnetic resonance imaging. Salivary alpha amylase, but not cortisol, increased in response to the trauma reminder. Salivary alpha amylase reactivity was associated with neural reactivity in the salience network in response to novel negative scenes and neural hypervigilance as indexed by reactivity to novel neutral scenes. Salivary alpha amylase might serve as a more reliable marker of trauma-related reactivity to negative affective information, and also as a marker of hypervigilance in the absence of threatening information. Copyright © 2015 Elsevier Ltd. All rights reserved.
Robarts, Daniel W H; Wolfe, Andrea D
2014-07-01
In the past few decades, many investigations in the field of plant biology have employed selectively neutral, multilocus, dominant markers such as inter-simple sequence repeat (ISSR), random-amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP) to address hypotheses at lower taxonomic levels. More recently, sequence-related amplified polymorphism (SRAP) markers have been developed, which are used to amplify coding regions of DNA with primers targeting open reading frames. These markers have proven to be robust and highly variable, on par with AFLP, and are attained through a significantly less technically demanding process. SRAP markers have been used primarily for agronomic and horticultural purposes, developing quantitative trait loci in advanced hybrids and assessing genetic diversity of large germplasm collections. Here, we suggest that SRAP markers should be employed for research addressing hypotheses in plant systematics, biogeography, conservation, ecology, and beyond. We provide an overview of the SRAP literature to date, review descriptive statistics of SRAP markers in a subset of 171 publications, and present relevant case studies to demonstrate the applicability of SRAP markers to the diverse field of plant biology. Results of these selected works indicate that SRAP markers have the potential to enhance the current suite of molecular tools in a diversity of fields by providing an easy-to-use, highly variable marker with inherent biological significance.
Robarts, Daniel W. H.; Wolfe, Andrea D.
2014-01-01
In the past few decades, many investigations in the field of plant biology have employed selectively neutral, multilocus, dominant markers such as inter-simple sequence repeat (ISSR), random-amplified polymorphic DNA (RAPD), and amplified fragment length polymorphism (AFLP) to address hypotheses at lower taxonomic levels. More recently, sequence-related amplified polymorphism (SRAP) markers have been developed, which are used to amplify coding regions of DNA with primers targeting open reading frames. These markers have proven to be robust and highly variable, on par with AFLP, and are attained through a significantly less technically demanding process. SRAP markers have been used primarily for agronomic and horticultural purposes, developing quantitative trait loci in advanced hybrids and assessing genetic diversity of large germplasm collections. Here, we suggest that SRAP markers should be employed for research addressing hypotheses in plant systematics, biogeography, conservation, ecology, and beyond. We provide an overview of the SRAP literature to date, review descriptive statistics of SRAP markers in a subset of 171 publications, and present relevant case studies to demonstrate the applicability of SRAP markers to the diverse field of plant biology. Results of these selected works indicate that SRAP markers have the potential to enhance the current suite of molecular tools in a diversity of fields by providing an easy-to-use, highly variable marker with inherent biological significance. PMID:25202637
Li, Chao-Ran; Li, Meng-Ning; Yang, Hua; Li, Ping; Gao, Wen
2018-06-01
Processing of herbal medicines is a characteristic pharmaceutical technique in Traditional Chinese Medicine, which can reduce toxicity and side effect, improve the flavor and efficacy, and even change the pharmacological action entirely. It is significant and crucial to perform a method to find chemical markers for differentiating herbal medicines in different processed degrees. The aim of this study was to perform a rapid and reasonable method to discriminate Moutan Cortex and its processed products, and to reveal the characteristics of chemical components depend on chemical markers. Thirty batches of Moutan Cortex and its processed products, including 11 batches of Raw Moutan Cortex (RMC), 9 batches of Moutan Cortex Tostus (MCT) and 10 batches of Moutan Cortex Carbonisatus (MCC), were directly injected in electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOF MS) for rapid analysis in positive and negative mode. Without chromatographic separation, each run was completed within 3 min. The raw MS data were automatically extracted by background deduction and molecular feature (MF) extraction algorithm. In negative mode, a total of 452 MFs were obtained and then pretreated by data filtration and differential analysis. After that, the filtered 85 MFs were treated by principal component analysis (PCA) to reduce the dimensions. Subsequently, a partial least squares discrimination analysis (PLS-DA) model was constructed for differentiation and chemical markers detection of Moutan Cortex in different processed degrees. The positive mode data were treated as same as those in negative mode. RMC, MCT and MCC were successfully classified. Moreover, 14 and 3 chemical markers from negative and positive mode respectively, were screened by the combination of their relative peak areas and the parameter variable importance in the projection (VIP) values in PLS-DA model. The content changes of these chemical markers were employed in order to illustrate chemical changes of Moutan Cortex after processed. These results showed that the proposed method which combined non-targeted metabolomics analysis with multivariate statistics analysis is reasonable and effective. It could not only be applied to discriminate herbal medicines and their processing products, but also to reveal the characteristics of chemical components during processing. Copyright © 2018. Published by Elsevier GmbH.
Springer, Mark S; Gatesy, John
2017-04-01
Various toothed whales (Odontoceti) are unique among mammals in lacking olfactory bulbs as adults and are thought to be anosmic (lacking the olfactory sense). At the molecular level, toothed whales have high percentages of pseudogenic olfactory receptor genes, but species that have been investigated to date retain an intact copy of the olfactory marker protein gene (OMP), which is highly expressed in olfactory receptor neurons and may regulate the temporal resolution of olfactory responses. One hypothesis for the retention of intact OMP in diverse odontocete lineages is that this gene is pleiotropic with additional functions that are unrelated to olfaction. Recent expression studies provide some support for this hypothesis. Here, we report OMP sequences for representatives of all extant cetacean families and provide the first molecular evidence for inactivation of this gene in vertebrates. Specifically, OMP exhibits independent inactivating mutations in six different odontocete lineages: four river dolphin genera (Platanista, Lipotes, Pontoporia, Inia), sperm whale (Physeter), and harbor porpoise (Phocoena). These results suggest that the only essential role of OMP that is maintained by natural selection is in olfaction, although a non-olfactory role for OMP cannot be ruled out for lineages that retain an intact copy of this gene. Available genome sequences from cetaceans and close outgroups provide evidence of inactivating mutations in two additional genes (CNGA2, CNGA4), which imply further pseudogenization events in the olfactory cascade of odontocetes. Selection analyses demonstrate that evolutionary constraints on all three genes (OMP, CNGA2, CNGA4) have been greatly reduced in Odontoceti, but retain a signature of purifying selection on the stem Cetacea branch and in Mysticeti (baleen whales). This pattern is compatible with the 'echolocation-priority' hypothesis for the evolution of OMP, which posits that negative selection was maintained in the common ancestor of Cetacea and was not relaxed significantly until the evolution of echolocation in Odontoceti. Copyright © 2017 Elsevier Inc. All rights reserved.
Clevenger, Josh; Chu, Ye; Chavarro, Carolina; Botton, Stephanie; Culbreath, Albert; Isleib, Thomas G; Holbrook, C C; Ozias-Akins, Peggy
2018-01-01
Late leaf spot (LLS; Cercosporidium personatum ) is a major fungal disease of cultivated peanut ( Arachis hypogaea ). A recombinant inbred line population segregating for quantitative field resistance was used to identify quantitative trait loci (QTL) using QTL-seq. High rates of false positive SNP calls using established methods in this allotetraploid crop obscured significant QTLs. To resolve this problem, robust parental SNPs were first identified using polyploid-specific SNP identification pipelines, leading to discovery of significant QTLs for LLS resistance. These QTLs were confirmed over 4 years of field data. Selection with markers linked to these QTLs resulted in a significant increase in resistance, showing that these markers can be immediately applied in breeding programs. This study demonstrates that QTL-seq can be used to rapidly identify QTLs controlling highly quantitative traits in polyploid crops with complex genomes. Markers identified can then be deployed in breeding programs, increasing the efficiency of selection using molecular tools. Key Message: Field resistance to late leaf spot is a quantitative trait controlled by many QTLs. Using polyploid-specific methods, QTL-seq is faster and more cost effective than QTL mapping.
Clevenger, Josh; Chu, Ye; Chavarro, Carolina; Botton, Stephanie; Culbreath, Albert; Isleib, Thomas G.; Holbrook, C. C.; Ozias-Akins, Peggy
2018-01-01
Late leaf spot (LLS; Cercosporidium personatum) is a major fungal disease of cultivated peanut (Arachis hypogaea). A recombinant inbred line population segregating for quantitative field resistance was used to identify quantitative trait loci (QTL) using QTL-seq. High rates of false positive SNP calls using established methods in this allotetraploid crop obscured significant QTLs. To resolve this problem, robust parental SNPs were first identified using polyploid-specific SNP identification pipelines, leading to discovery of significant QTLs for LLS resistance. These QTLs were confirmed over 4 years of field data. Selection with markers linked to these QTLs resulted in a significant increase in resistance, showing that these markers can be immediately applied in breeding programs. This study demonstrates that QTL-seq can be used to rapidly identify QTLs controlling highly quantitative traits in polyploid crops with complex genomes. Markers identified can then be deployed in breeding programs, increasing the efficiency of selection using molecular tools. Key Message: Field resistance to late leaf spot is a quantitative trait controlled by many QTLs. Using polyploid-specific methods, QTL-seq is faster and more cost effective than QTL mapping. PMID:29459876
On prediction of genetic values in marker-assisted selection.
Lange, C; Whittaker, J C
2001-01-01
We suggest a new approximation for the prediction of genetic values in marker-assisted selection. The new approximation is compared to the standard approach. It is shown that the new approach will often provide substantially better prediction of genetic values; furthermore the new approximation avoids some of the known statistical problems of the standard approach. The advantages of the new approach are illustrated by a simulation study in which the new approximation outperforms both the standard approach and phenotypic selection. PMID:11729177
Selection of recombinant MVA by rescue of the essential D4R gene.
Ricci, Patricia S; Schäfer, Birgit; Kreil, Thomas R; Falkner, Falko G; Holzer, Georg W
2011-12-12
Modified vaccinia virus Ankara (MVA) has become a promising vaccine vector due to its immunogenicity and its proven safety in humans. As a general approach for stringent and rapid selection of recombinant MVA, we assessed marker rescue of the essential viral D4R gene in an engineered deletion mutant that is fully replication defective in wild-type cells. Recombinant, replicating virus was obtained by re-introduction of the deleted viral gene as a dominant selection marker into the deletion mutant.
Fonseca-Alves, Carlos Eduardo; Kobayashi, Priscila Emiko; Rivera Calderón, Luis Gabriel; Felisbino, Sérgio Luis; Rinaldi, Jaqueline de Carvalho; Drigo, Sandra Aparecida; Rogatto, Silvia Regina; Laufer-Amorim, Renée
2018-01-01
An unusual variant of prostate adenocarcinoma (PC) expressing nuclear p63 in secretory cells instead of the typical basal expression has been reported in men. Nevertheless, the biological behavior and clinical significance of this phenomenon is unknown. In dogs, this unusual PC subtype has not been described. In this study, p63 immunoexpression was investigated in 90 canine PCs and 20 normal prostate tissues (NT). The p63 expression pattern in luminal or basal cells was confirmed in a selected group of 26 PCs and 20 NT by immunohistochemistry and/or Western blotting assays. Eleven canine PC samples aberrantly expressing p63 (p63+) in secretory cells were compared with 15 p63 negative (p63-) cases in the context of several molecular markers (high molecular weight cytokeratin-HMWC, CK8/18, CK5, AR, PSA, chromogranin, NKX3.1, PTEN, AKT and C-MYC). P63+ samples were positive for CK5, HMWC and CK8/18 and negative for PSA, NKX3.1, PTEN and chromogranin. Five p63+ PCs were negative for AR, and the remaining six samples had low AR expression. In contrast, p63- PC showed AR and PSA positive expression in all 15 samples. Only five p63- PCs were positive for CK5. Both p63+ and p63- PC samples showed higher cytoplasmic AKT expression and nuclear C-MYC staining in comparison with normal tissues. Metastatic (N = 12) and non-metastatic (N = 14) PCs showed similar immunoexpression for all markers tested. In contrast to human PC, canine PC aberrantly expressing p63 showed higher expression levels of HMWC and CK5 and lower levels of NKX3.1. Canine p63+ PC is a very rare PC group showing a distinct phenotype compared to typical canine PC, including AR and PSA negative expression. Although in a limited number of cases, p63 expression was not associated with metastasis in canine PC, and cytoplasmic p63 expression was observed in animals with shorter survival time, similar to human PC cases.
Circulating Tumor Cells as an Independent Predictor of Survival in Advanced Gastric Cancer.
Okabe, H; Tsunoda, S; Hosogi, H; Hisamori, S; Tanaka, E; Tanaka, S; Sakai, Y
2015-11-01
When the indication for surgery of highly advanced gastric cancer is considered, careful selection of the patients is important. In addition to tumor-node-metastasis factors and peritoneal lavage cytology (CY), which are important predictors of prognosis, detection of circulating tumor cells (CTCs) could be another potential marker. This study prospectively evaluated CTCs using a semi-automated immunomagnetic separation system (CellSearch) for 136 patients with advanced gastric cancer to determine the frequency of CTC positivity. For 123 patients who also had their CY evaluated, the significance of both CTC and CY, was investigated as a potential biomarker to predict progression-free survival (PFS) or to monitor the therapeutic effect. In 25 patients (18.4 %), CTCs were positive. Positive CTC counts were more common for tumors with diffuse histologic type and distant metastasis. The PFS of CTC-positive patients was significantly shorter than that of CTC-negative patients (hazard ratio 2.03; P = 0.016). A multivariate analysis of 123 patients showed that CTC and CY as well as performance status and macroscopic distant metastasis were independent factors for PFS. When both CTC and CY were converted to negative values by therapeutic interventions, long-term PFS was achieved. Detection of CTCs was an independent predictor of a shorter PFS in advanced gastric cancer. For selecting patients who require intensive treatment, CTCs could be a valuable biomarker. The combined status of CTC and CY would be useful in selecting patients for radical surgery. Further investigation with a larger number of patients is necessary to establish the importance of CTCs.
2013-08-01
cancers that are ‘‘triple-negative’’ for the clinical markers ESR1 , PGR, and HER2 typically belong to the Basal-like molecular subtype. Defective Rb, p53...triple- negative’’ by clinical diagnostic markers ( ESR1 , PGR, and HER2 negative) are heterogeneous in their clinical behavior, morphology, and
Human Myocardial Pericytes: Multipotent Mesodermal Precursors Exhibiting Cardiac Specificity
Chen, William C.W.; Baily, James E.; Corselli, Mirko; Diaz, Mary; Sun, Bin; Xiang, Guosheng; Gray, Gillian A.; Huard, Johnny; Péault, Bruno
2015-01-01
Perivascular mesenchymal precursor cells (i.e. pericytes) reside in skeletal muscle where they contribute to myofiber regeneration; however, the existence of similar microvessel-associated regenerative precursor cells in cardiac muscle has not yet been documented. We tested whether microvascular pericytes within human myocardium exhibit phenotypes and multipotency similar to their anatomically and developmentally distinct counterparts. Fetal and adult human heart pericytes (hHPs) express canonical pericyte markers in situ, including CD146, NG2, PDGFRβ, PDGFRα, αSMA, and SM-MHC, but not CD117, CD133 and desmin, nor endothelial cell (EC) markers. hHPs were prospectively purified to homogeneity from ventricular myocardium by flow cytometry, based on a combination of positive- (CD146) and negative-selection (CD34, CD45, CD56, and CD117) cell lineage markers. Purified hHPs expanded in vitro were phenotypically similar to human skeletal muscle-derived pericytes (hSkMPs). hHPs express MSC markers in situ and exhibited osteo- chondro-, and adipogenic potentials but, importantly, no ability for skeletal myogenesis, diverging from pericytes of all other origins. hHPs supported network formation with/without ECs in Matrigel cultures; hHPs further stimulated angiogenic responses under hypoxia, markedly different from hSkMPs. The cardiomyogenic potential of hHPs was examined following 5-azacytidine treatment and neonatal cardiomyocyte co-culture in vitro, and intramyocardial transplantation in vivo. Results indicated cardiomyocytic differentiation in a small fraction of hHPs. In conclusion, human myocardial pericytes share certain phenotypic and developmental similarities with their skeletal muscle homologs, yet exhibit different antigenic, myogenic, and angiogenic properties. This is the first example of an anatomical restriction in the developmental potential of pericytes as native mesenchymal stem cells. PMID:25336400
Rodríguez-Iglesias, Beatriz; Novella-Maestre, Edurne; Herraiz, Sonia; Díaz-García, César; Pellicer, Nuria; Pellicer, Antonio
2015-12-01
To develop a novel molecular panel of markers to detect breast cancer (BC) disseminated malignant cells in ovarian tissue, and to improve the safety of ovarian tissue transplantation. Experimental study. University hospital. Ten ovarian biopsies from healthy patients, 13 biopsies with diagnosed BC metastasis, and 4 biopsies from primary BC tumor for designing a diagnostic panel of BC cell contamination; 60 ovarian biopsies from BC patients undergoing fertility preservation for validating the panel. Female nude mice. A novel panel for BC malignant cell detection by reverse-transcription polymerase chain reaction (RT-PCR), inmmunohistochemical analysis, in vitro invasion assay and xenotransplantation assayed in ovarian tissue from BC patients. Expression of GCDFP15, MGB1, SBEM, MUC1, WT-1, and NY-BR-01, selected as markers, assessed by quantitative RT-PCR in samples with confirmed BC metastasis. The most sensitive markers were confirmed by immunohistochemistry, and tested in vitro and in vivo. GCDFP15, MGB1, and SBEM were the most sensitive and specific markers to detect BC metastatic cells when at least one was expressed by quantitative RT-PCR. The panel was validated in 60 patients and confirmed in an in vitro invasion assay, where no invasive cells were observed. Samples negative for BC cells cannot develop disease when xenografted. GCDFP15, MGB1, and SBEM were the most sensitive molecules to create a diagnostic panel for BC malignant cell contamination, which may make ovarian tissue cryopreservation and transplantation a safe technique for fertility preservation in BC patients. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Galeano, Carlos H.; Fernandez, Andrea C.; Franco-Herrera, Natalia; Cichy, Karen A.; McClean, Phillip E.; Vanderleyden, Jos; Blair, Matthew W.
2011-01-01
Map-based cloning and fine mapping to find genes of interest and marker assisted selection (MAS) requires good genetic maps with reproducible markers. In this study, we saturated the linkage map of the intra-gene pool population of common bean DOR364×BAT477 (DB) by evaluating 2,706 molecular markers including SSR, SNP, and gene-based markers. On average the polymorphism rate was 7.7% due to the narrow genetic base between the parents. The DB linkage map consisted of 291 markers with a total map length of 1,788 cM. A consensus map was built using the core mapping populations derived from inter-gene pool crosses: DOR364×G19833 (DG) and BAT93×JALO EEP558 (BJ). The consensus map consisted of a total of 1,010 markers mapped, with a total map length of 2,041 cM across 11 linkage groups. On average, each linkage group on the consensus map contained 91 markers of which 83% were single copy markers. Finally, a synteny analysis was carried out using our highly saturated consensus maps compared with the soybean pseudo-chromosome assembly. A total of 772 marker sequences were compared with the soybean genome. A total of 44 syntenic blocks were identified. The linkage group Pv6 presented the most diverse pattern of synteny with seven syntenic blocks, and Pv9 showed the most consistent relations with soybean with just two syntenic blocks. Additionally, a co-linear analysis using common bean transcript map information against soybean coding sequences (CDS) revealed the relationship with 787 soybean genes. The common bean consensus map has allowed us to map a larger number of markers, to obtain a more complete coverage of the common bean genome. Our results, combined with synteny relationships provide tools to increase marker density in selected genomic regions to identify closely linked polymorphic markers for indirect selection, fine mapping or for positional cloning. PMID:22174773
Li, Si-Fa; Tang, Shou-Jie; Cai, Wan-Qi
2010-04-01
The NEW GIFT Nile tilapia (Oreochromis niloticus niloticus L.) is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new variety has been extended in most of areas of China. The management of genetically improved strains, including the genetic markers for identification is needed urgently. RAPD analysis was conducted and their conversion to SCAR markers was developed. From NEW GIFT Nile tilapia, two strain-specific RAPD bands, S(304 )(624 bp ) and S(36 )(568 bp ) were identified. The strain-specific RAPD bands were gel-purified, cloned, and sequenced. Locus-specific primers were then designed to amplify the strain-specific bands. PCR amplification was conducted to test the variations in allele frequencies of two converted SCAR markers among the NEW GIFT Nile tilapia and its base strains, as well as 7 additional farmed strains worldwide. The frequency of SCAR marker I (553 bp) was 85.7% in NEW GIFT Nile tilapia, but 16.7% in the base strain. The frequency of SCAR marker II (558 bp) was 91.4% in NEW GIFT Nile tilapia, but 0% - 70% in the 7 other strains. In order to confirm the utility of these two markers, an examination was conducted for a wild population from Egypt, resulted the frequency of SCAR I and II was 10% and 70%, respectively, much lower than that of New GIFT strain. The increase in allele frequency of these two SCAR markers suggests that these markers might be genetically linked to the quantitative trait loci (QTL) underlining the performance traits by long term selection, and indicate the bright potential of SCAR marker technology for tracking generations during selection progress and for distinguishing among genetically improved strain and other strains.
Mourad, Amira M I; Sallam, Ahmed; Belamkar, Vikas; Wegulo, Stephen; Bowden, Robert; Jin, Yue; Mahdy, Ezzat; Bakheit, Bahy; El-Wafaa, Atif A; Poland, Jesse; Baenziger, Peter S
2018-01-01
Stem rust (caused by Puccinia graminis f. sp. tritici Erikss. & E. Henn.), is a major disease in wheat ( Triticum aestivium L.). However, in recent years it occurs rarely in Nebraska due to weather and the effective selection and gene pyramiding of resistance genes. To understand the genetic basis of stem rust resistance in Nebraska winter wheat, we applied genome-wide association study (GWAS) on a set of 270 winter wheat genotypes (A-set). Genotyping was carried out using genotyping-by-sequencing and ∼35,000 high-quality SNPs were identified. The tested genotypes were evaluated for their resistance to the common stem rust race in Nebraska (QFCSC) in two replications. Marker-trait association identified 32 SNP markers, which were significantly (Bonferroni corrected P < 0.05) associated with the resistance on chromosome 2D. The chromosomal location of the significant SNPs (chromosome 2D) matched the location of Sr6 gene which was expected in these genotypes based on pedigree information. A highly significant linkage disequilibrium (LD, r 2 ) was found between the significant SNPs and the specific SSR marker for the Sr6 gene ( Xcfd43 ). This suggests the significant SNP markers are tagging Sr6 gene. Out of the 32 significant SNPs, eight SNPs were in six genes that are annotated as being linked to disease resistance in the IWGSC RefSeq v1.0. The 32 significant SNP markers were located in nine haplotype blocks. All the 32 significant SNPs were validated in a set of 60 different genotypes (V-set) using single marker analysis. SNP markers identified in this study can be used in marker-assisted selection, genomic selection, and to develop KASP (Kompetitive Allele Specific PCR) marker for the Sr6 gene. Novel SNPs for Sr6 gene, an important stem rust resistant gene, were identified and validated in this study. These SNPs can be used to improve stem rust resistance in wheat.
Cha, Young-Soon; Ji, Hyeonso; Yun, Doh-Won; Ahn, Byoung-Ohg; Lee, Myung Chul; Suh, Seok-Cheol; Lee, Chun Seok; Ahn, Eok Keun; Jeon, Yong-Hee; Jin, Il-Doo; Sohn, Jae-Keun; Koh, Hee-Jong; Eun, Moo-Young
2008-08-31
The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.
Ower, G D; Hunt, J; Sakaluk, S K
2017-02-01
Although the strength and form of sexual selection on song in male crickets have been studied extensively, few studies have examined selection on the morphological structures that underlie variation in males' song, particularly in wild populations. Geometric morphometric techniques were used to measure sexual selection on the shape, size and symmetry of both top and bottom tegmina in wild populations of sagebrush crickets, a species in which nuptial feeding by females imposes an unambiguous phenotypic marker on males. The size of the tegmina negatively covaried with song dominant frequency and positively covaried with song pulse duration. Sexual selection was more intense on the bottom tegmen, conceivably because it interacts more freely with the subtegminal airspace, which may play a role in song amplification. An expanded coastal/subcostal region was one of the phenotypes strongly favoured by disruptive selection on the bottom tegmen, an adaptation that may form a more effective seal with the thorax to prevent noise cancellation. Directional selection also favoured increased symmetry in tegminal shape. Assuming more symmetrical males are better able to buffer against developmental noise, the song produced by these males may make them more attractive to females. Despite the strong stabilizing selection documented previously on the dominant frequency of the song, stabilizing selection on the resonator that regulates dominant frequency was surprisingly absent. Nonetheless, wing morphology had an important influence on song structure and appears to be subject to significant linear and nonlinear sexual selection through female mate choice. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.
USDA-ARS?s Scientific Manuscript database
Expressed sequence tag (EST) simple sequence repeats (SSRs) in Prunus were mined, and flanking primers designed and used for genome-wide characterization and selection of primers to optimize marker distribution and reliability. A total of 12,618 contigs were assembled from 84,727 ESTs, along with 34...
Andrew D. Bower; Bryce A. Richardson; Valerie Hipkins; Regina Rochefort; Carol Aubry
2011-01-01
Analysis of "neutral" molecular markers and "adaptive" quantitative traits are common methods of assessing genetic diversity and population structure. Molecular markers typically reflect the effects of demographic and stochastic processes but are generally assumed to not reflect natural selection. Conversely, quantitative (or "adaptive")...
Bim-mediated apoptosis is not necessary for thymic negative selection to ubiquitous self-antigens.
Hu, Qian; Sader, Alyssa; Parkman, Julia C; Baldwin, Troy A
2009-12-15
T cell education in the thymus is critical for establishing a functional, yet self-tolerant, T cell repertoire. Negative selection is a key process in enforcing self-tolerance. There are many questions that surround the mechanism of negative selection, but it is currently held that apoptosis initiated by Bim and/or Nur77 is critical for negative selection. Recent studies, however, have questioned the necessity of Bim in maintaining both central and peripheral T cell tolerance. To reconcile these apparently contradictory findings, we examined the role of Bim in negative selection in the well-characterized, physiological HY(cd4) mouse model. We found that while Bim expression was required for CD4(+)CD8(+) double-positive thymocyte apoptosis, it was not required for negative selection. Furthermore, Bim deficiency did not alter the frequency or affinity of male reactive cells that escape negative selection in an oligoclonal repertoire. Collectively, these studies indicate that negative selection occurs efficiently in the absence of apoptosis and suggest that the current paradigm of negative selection requiring apoptosis be revisited.
Baseline series fragrance markers fail to predict contact allergy.
Mann, Jack; McFadden, John P; White, Jonathan M L; White, Ian R; Banerjee, Piu
2014-05-01
Negative patch test results with fragrance allergy markers in the European baseline series do not always predict a negative reaction to individual fragrance substances. To determine the frequencies of positive test reactions to the 26 fragrance substances for which labelling is mandatory in the EU, and how effectively reactions to fragrance markers in the baseline series predict positive reactions to the fragrance substances that are labelled. The records of 1951 eczema patients, routinely tested with the labelled fragrance substances and with an extended European baseline series in 2011 and 2012, were retrospectively reviewed. Two hundred and eighty-one (14.4%) (71.2% females) reacted to one or more allergens from the labelled-fragrance substance series and/or a fragrance marker from the European baseline series. The allergens that were positive with the greatest frequencies were cinnamyl alcohol (48; 2.46%), Evernia furfuracea (44; 2.26%), and isoeugenol (40; 2.05%). Of the 203 patients who reacted to any of the 26 fragrances in the labelled-fragrance substance series, only 117 (57.6%) also reacted to a fragrance marker in the baseline series. One hundred and seven (52.7%) reacted to either fragrance mix I or fragrance mix II, 28 (13.8%) reacted to Myroxylon pereirae, and 13 (6.4%) reacted to hydroxyisohexyl 3-cyclohexene carboxaldehyde. These findings confirm that the standard fragrance markers fail to identify patients with contact allergies to the 26 fragrances. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Kyongo, Jordan K; Crucitti, Tania; Menten, Joris; Hardy, Liselotte; Cools, Piet; Michiels, Johan; Delany-Moretlwe, Sinead; Mwaura, Mary; Ndayisaba, Gilles; Joseph, Sarah; Fichorova, Raina; van de Wijgert, Janneke; Vanham, Guido; Ariën, Kevin K; Jespers, Vicky
2015-05-01
Data on immune mediators in the genital tract and the factors that modulate them in sub-Saharan women are limited. Cervicovaginal lavage (CVL) samples from 430 sexually active women from Kenya, South Africa, and Rwanda were analyzed for 12 soluble immune mediators using Bio-Plex and Meso Scale Discovery multiplex platforms, as well as single enzyme-linked immunosorbent assays. Ten bacterial species were quantified in vaginal swab samples. Bacterial vaginosis (BV) was defined by Nugent scoring. CVL samples from HIV-infected women showed a clear-cut proinflammatory profile. Pregnant women, adolescents, and women engaging in traditional vaginal practices differed in specific soluble markers compared to reference groups of adult HIV-negative women. Cervical mucus, cervical ectopy, abnormal vaginal discharge, and having multiple sex partners were each associated with an increase in inflammatory mediators. The levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12(p70), and IL-8 were elevated, whereas the IL-1RA/IL-1(α+β) ratio decreased in women with BV. The level of gamma interferon-induced protein 10 was lower in BV-positive than in BV-negative women, suggesting its suppression as a potential immune evasion mechanism by BV-associated bacteria. Lactobacillus crispatus and Lactobacillus vaginalis were associated with decreased proinflammatory cytokines and each BV-associated species with increased proinflammatory cytokines. Remarkably, the in vitro anti-HIV activity of CVL samples from BV-positive women was stronger than that of BV-negative women. In conclusion, we found significant associations of factors, including vaginal microbiota, which can influence immune mediators in the vaginal environment in sexually active women. These factors need to be considered when establishing normative levels or pathogenic cutoffs of biomarkers of inflammation and associated risks in African women. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Kyongo, Jordan K.; Crucitti, Tania; Menten, Joris; Hardy, Liselotte; Cools, Piet; Michiels, Johan; Delany-Moretlwe, Sinead; Mwaura, Mary; Ndayisaba, Gilles; Joseph, Sarah; Fichorova, Raina; van de Wijgert, Janneke; Vanham, Guido; Ariën, Kevin K.
2015-01-01
Data on immune mediators in the genital tract and the factors that modulate them in sub-Saharan women are limited. Cervicovaginal lavage (CVL) samples from 430 sexually active women from Kenya, South Africa, and Rwanda were analyzed for 12 soluble immune mediators using Bio-Plex and Meso Scale Discovery multiplex platforms, as well as single enzyme-linked immunosorbent assays. Ten bacterial species were quantified in vaginal swab samples. Bacterial vaginosis (BV) was defined by Nugent scoring. CVL samples from HIV-infected women showed a clear-cut proinflammatory profile. Pregnant women, adolescents, and women engaging in traditional vaginal practices differed in specific soluble markers compared to reference groups of adult HIV-negative women. Cervical mucus, cervical ectopy, abnormal vaginal discharge, and having multiple sex partners were each associated with an increase in inflammatory mediators. The levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12(p70), and IL-8 were elevated, whereas the IL-1RA/IL-1(α+β) ratio decreased in women with BV. The level of gamma interferon-induced protein 10 was lower in BV-positive than in BV-negative women, suggesting its suppression as a potential immune evasion mechanism by BV-associated bacteria. Lactobacillus crispatus and Lactobacillus vaginalis were associated with decreased proinflammatory cytokines and each BV-associated species with increased proinflammatory cytokines. Remarkably, the in vitro anti-HIV activity of CVL samples from BV-positive women was stronger than that of BV-negative women. In conclusion, we found significant associations of factors, including vaginal microbiota, which can influence immune mediators in the vaginal environment in sexually active women. These factors need to be considered when establishing normative levels or pathogenic cutoffs of biomarkers of inflammation and associated risks in African women. PMID:25761460
Adamec, Robert; Toth, Mate; Haller, Jozsef; Halasz, Jozsef; Blundell, Jacqueline
2012-02-01
This study had two purposes. First: to compare predator and water submersion stress cFos activation in medial prefrontal cortices (mPFC) and the medial amygdala (MeA). Second: to identify markers of vulnerability to stressors within these areas. Rats were either predator or submersion stressed and tested 1.75 h later for anxiety. Immediately thereafter, rats were sacrificed and cFos expression was examined. Predator and submersion stress equally increased anxiety-like behavior in the elevated plus maze (EPM) and hole board. To examine vulnerability, rats which were less anxious (LA) and more (highly) anxious (MA) in the EPM were selected from among handled control and stressed animals. LA stressed rats were considered stress non-responsive while MA stressed rats were considered stress responsive. Predator stress, but not submersion stress, activated MeA cFos. CFos expression of mPFC cells was elevated in LA rats and reduced in MA rats in predator stressed animals only, correlating negatively with anxiety. These findings are consistent with data implicating greater mPFC excitability in protection against the effects on affect of traumatic stress. The findings also suggest that this conclusion is stressor specific, applying to predator stress but not submersion stress. Both stressors have been suggested to model hyperarousal and comorbid anxiety aspects of PTSD in humans. Hence the use of these paradigms to identify brain bases of vulnerability and resilience to traumatic stress in PTSD has translation potential. On the other hand, our evidence of stressor specificity of vulnerability/resilience markers raises a caution. The data suggest that preclinical markers of vulnerability/resilience in a given stress paradigm are at best suggestive, and translational value must ultimately be confirmed in humans. Copyright © 2011 Elsevier Inc. All rights reserved.
Jia, Dongjie; Shen, Fei; Wang, Yi; Wu, Ting; Xu, Xuefeng; Zhang, Xinzhong; Han, Zhenhai
2018-05-11
Many efforts have been made to map quantitative trait loci (QTLs) to facilitate practical marker-assisted selection (MAS) in plants. In the present study, we identified four genome-wide major QTLs responsible for apple fruit acidity by MapQTL and BSA-seq analyses using two independent pedigree-based populations. Candidate genes were screened in major QTL regions, and three functional gene markers, including a non-synonymous A/G single nucleotide polymorphism (SNP) in the coding region of MdPP2CH, a 36-bp insertion in the promoter of MdSAUR37, and a previously reported SNP in MdALMTII, were validated to influence the malate content of apple fruits. In addition, MdPP2CH inactivated three vacuolar H + -ATPases (MdVHA-A3, MdVHA-B2 and MdVHA-D2) and one aluminium-activated malate transporter (MdALMTII) via dephosphorylation and negatively influenced fruit malate accumulation. The dephosphotase activity of MdPP2CH was suppressed by MdSAUR37, which implied a higher hierarchy of genetic interaction. Therefore, the MdSAUR37/MdPP2CH/MdALMTII chain cascaded hierarchical epistatic genetic effects to precisely determine apple fruit malate content. An A/G SNP (-1010) on MdMYB44 promoter region from a major QTL (qtl08.1) was closely associated with fruit malate content. The predicted phenotype values (PPVs) were estimated using the tentative genotype values of the gene markers, and the PPVs were significantly correlated with the observed phenotype values. Our findings provide an insight into plant genome-based selection in apples and will aid in conducting research to understand the physiological fundamentals of quantitative genetics. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Vidal, Newton Medeiros; Grazziotin, Ana Laura; Ramos, Helaine Christine Cancela; Pereira, Messias Gonzaga; Venancio, Thiago Motta
2014-01-01
Carica papaya (papaya) is an economically important tropical fruit. Molecular marker-assisted selection is an inexpensive and reliable tool that has been widely used to improve fruit quality traits and resistance against diseases. In the present study we report the development and validation of an atlas of papaya simple sequence repeat (SSR) markers. We integrated gene predictions and functional annotations to provide a gene-centered perspective for marker-assisted selection studies. Our atlas comprises 160,318 SSRs, from which 21,231 were located in genic regions (i.e. inside exons, exon-intron junctions or introns). A total of 116,453 (72.6%) of all identified repeats were successfully mapped to one of the nine papaya linkage groups. Primer pairs were designed for markers from 9,594 genes (34.5% of the papaya gene complement). Using papaya-tomato orthology assessments, we assembled a list of 300 genes (comprising 785 SSRs) potentially involved in fruit ripening. We validated our atlas by screening 73 SSR markers (including 25 fruit ripening genes), achieving 100% amplification rate and uncovering 26% polymorphism rate between the parental genotypes (Sekati and JS12). The SSR atlas presented here is the first comprehensive gene-centered collection of annotated and genome positioned papaya SSRs. These features combined with thousands of high-quality primer pairs make the atlas an important resource for the papaya research community.
Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun
2016-01-01
Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to “Gopoong” and “K-1” were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information. PMID:27271615
Pode-Shakked, Naomi; Pleniceanu, Oren; Gershon, Rotem; Shukrun, Rachel; Kanter, Itamar; Bucris, Efrat; Pode-Shakked, Ben; Tam, Gal; Tam, Hadar; Caspi, Revital; Pri-Chen, Sara; Vax, Einav; Katz, Guy; Omer, Dorit; Harari-Steinberg, Orit; Kalisky, Tomer; Dekel, Benjamin
2016-03-29
When assembling a nephron during development a multipotent stem cell pool becomes restricted as differentiation ensues. A faulty differentiation arrest in this process leads to transformation and initiation of a Wilms' tumor. Mapping these transitions with respective surface markers affords accessibility to specific cell subpopulations. NCAM1 and CD133 have been previously suggested to mark human renal progenitor populations. Herein, using cell sorting, RNA sequencing, in vitro studies with serum-free media and in vivo xenotransplantation we demonstrate a sequential map that links human kidney development and tumorigenesis; In nephrogenesis, NCAM1(+)CD133(-) marks SIX2(+) multipotent renal stem cells transiting to NCAM1(+)CD133(+) differentiating segment-specific SIX2(-) epithelial progenitors and NCAM1(-)CD133(+) differentiated nephron cells. In tumorigenesis, NCAM1(+)CD133(-) marks SIX2(+) blastema that includes the ALDH1(+) WT cancer stem/initiating cells, while NCAM1(+)CD133(+) and NCAM1(-)CD133(+) specifying early and late epithelial differentiation, are severely restricted in tumor initiation capacity and tumor self-renewal. Thus, negative selection for CD133 is required for defining NCAM1(+) nephron stem cells in normal and malignant nephrogenesis.
HURTLE CELLS IMMUNOHISTOCHEMICAL ACTIVITIES IN HASHIMOTO THYROIDITIS PARENCHYMA.
Tsagareli, Z; Kvachadze, T; Melikadze, E; Metreveli, L; Nikobadze, E; Gogiashvili, L
2016-11-01
The present study was designed to evaluate the participation and utility of Hǘrtle cells morphological requirment and transformation under Hashimoto autoimmune thyroiditis versus Riedel´s struma. Several markers have been evaluated to detect induced activities of Hǘrtle cells. Study subject - specimens (tissue fragments) collected from TG surgery (thyroidectomy) for mollecular (receptor) diagnosis of Hǘrtle cells activities using routine histological and immunohistochemical samples. 89 cases were selected in Hashimoto thyroiditis diagnosis with Hǘrtle cells history (adenoma and adenomatous grouth of oncocytes). Markers as: TSH receptors, TTF-1, S-100 protein, also anti-TPO and anti-TG levels in blood plasm were detected. It was shown that solid cell claster-nests like agregation of oncocytes and adenomatous growth foci in parafollicular areas with anti-TPO and anti-TG antibodies levels arising while Riedel´s struma shown only large intra- and extra glandular inflammatory proliferative fibrosing process. Large positive expression of TTF-1 and S-100 protein and the negative reaction of TSH receptor factor suggest that Thyroid parenchyma disorganization and mollecular biological atypia with Hǘrtle cells are proceses due to hypothyreoidismus, as well as neuroectodermal cells prominent activities in 70% of Hashimoto cases.
Age differences in gain- and loss-motivated attention.
Williams, Ryan S; Biel, Anna Lena; Dyson, Benjamin J; Spaniol, Julia
2017-02-01
Adaptive gain theory (Aston-Jones & Cohen, 2005) suggests that the phasic release of norepinephrine (NE) to cortical areas reflects changes in the utility of ongoing tasks. In the context of aging, this theory raises interesting questions, given that the motivations of older adults differ from those of younger adults. According to socioemotional selectivity theory (Carstensen, Isaacowitz, & Charles, 1999), aging is associated with greater emphasis on emotion-regulation goals, leading older adults to prioritize positive over negative information. This suggests that the phasic release of NE in response to threatening stimuli may be diminished in older adults. In the present study, younger adults (aged 18-34years) and older adults (60-82years) completed the Attention Network Test (ANT), modified to include an incentive manipulation. A behavioral index of attentional alerting served as a marker of phasic arousal. For younger adults, this marker correlated with the effect of both gain and loss incentives on performance. For older adults, in contrast, the correlation between phasic arousal and incentive sensitivity held for gain incentives only. These findings suggest that the enlistment of phasic NE activity may be specific to approach-oriented motivation in older adults. Copyright © 2016. Published by Elsevier Inc.
NASA Astrophysics Data System (ADS)
Sun, Yanhong; Li, Qing; Wang, Guiying; Zhu, Dongmei; Chen, Jian; Li, Pei; Tong, Jingou
2017-05-01
Myostatin ( MSTN) is a member of the transforming growth factor-β gene superfamily that negatively regulates skeletal muscle development and growth. In the present study, partial genomic fragments of Myostatin-1 ( MSTN-1) in two commercial hatchery populations of Ancherythroculter nigrocauda, an economically important freshwater fish, were screened for single nucleotide polymorphisms (SNPs) and then genotyped by direct sequencing of PCR products. Five SNPs were identified in intron 1 and exon 2, including a non-synonymous mutation causing an amino acid change (Val to Ile) at position 180. Association analyses based on 300 individuals revealed that the g.1129T>C SNP locus was significantly associated with total length (TL), body length (BL), body height (BH) and body weight (BW) in 6- and 18-month-old populations, while the g.1289G>A locus was significantly associated with BH and BW in the 6-month-old population. Haplotype analyses revealed that fish with the genotype combinations TC/TC or TC/GA showed better growth performance. Our results suggest that g.1129T>C and g.1289G>A have positive effects on growth traits and may be candidate gene markers for marker-assisted selection in A. nigrocauda.
Ultrasound internal tattooing.
Couture, Olivier; Faivre, Magalie; Pannacci, Nicolas; Babataheri, Avin; Servois, Vincent; Tabeling, Patrick; Tanter, Mickael
2011-02-01
The ability of remotely tagging tissues in a controlled and three-dimensional manner during preoperative imaging could greatly help surgeons to identify targets for resection. The authors' objective is to selectively and noninvasively deposit markers under image guidance for such internal tattooing. This study describes the production of new ultrasound-inducible droplets carrying large payloads of fluorescent markers and the in vivo proof of concept of their remote and controlled deposition via focused ultrasound. The droplets are monodispersed multiple emulsions produced in a microfluidic system, consisting of aqueous fluorescein in perfluorocarbon in water. Their conversion (either by vaporization or cavitation) is performed remotely using a clinical ultrasonic imaging probe. When submitted to 5 MHz imaging pulses, the droplets vaporize in vitro at 1.4 MPa peak-negative pressure and eject their content. After several seconds, a brightly fluorescent spot (0.5 mm diameter) is observed at the focus of the transducer. Experiments in the chorioallantoique membrane of chicken eggs and chicken embryo demonstrate that the spot is stable and is easily seen by naked eye. These ultrasound-inducible multiple emulsions could be used to deliver large amounts of contrast agents, chemotherapy, and genetic materials in vivo using a conventional ultrasound scanner.
Ma, G J; Song, Q J; Markell, S G; Qi, L L
2018-07-01
A novel rust resistance gene, R 15 , derived from the cultivated sunflower HA-R8 was assigned to linkage group 8 of the sunflower genome using a genotyping-by-sequencing approach. SNP markers closely linked to R 15 were identified, facilitating marker-assisted selection of resistance genes. The rust virulence gene is co-evolving with the resistance gene in sunflower, leading to the emergence of new physiologic pathotypes. This presents a continuous threat to the sunflower crop necessitating the development of resistant sunflower hybrids providing a more efficient, durable, and environmentally friendly host plant resistance. The inbred line HA-R8 carries a gene conferring resistance to all known races of the rust pathogen in North America and can be used as a broad-spectrum resistance resource. Based on phenotypic assessments of 140 F 2 individuals derived from a cross of HA 89 with HA-R8, rust resistance in the population was found to be conferred by a single dominant gene (R 15 ) originating from HA-R8. Genotypic analysis with the currently available SSR markers failed to find any association between rust resistance and any markers. Therefore, we used genotyping-by-sequencing (GBS) analysis to achieve better genomic coverage. The GBS data showed that R 15 was located at the top end of linkage group (LG) 8. Saturation with 71 previously mapped SNP markers selected within this region further showed that it was located in a resistance gene cluster on LG8, and mapped to a 1.0-cM region between three co-segregating SNP makers SFW01920, SFW00128, and SFW05824 as well as the NSA_008457 SNP marker. These closely linked markers will facilitate marker-assisted selection and breeding in sunflower.
Specialized sperm function tests in varicocele and the future of andrology laboratory
Majzoub, Ahmad; Esteves, Sandro C; Gosálvez, Jaime; Agarwal, Ashok
2016-01-01
Varicocele is a common medical condition entangled with many controversies. Though it is highly prevalent in men with infertility, still it marks its presence in males who do have normal fertility. Determining which patients are negatively affected by varicocele would enable clinicians to better select those men who benefitted the most from surgery. Since conventional semen analysis has been limited in its ability to evaluate the negative effects of varicocele on fertility, a multitude of specialized laboratory tests have emerged. In this review, we examine the role and significance of specialized sperm function tests with regards to varicocele. Among the various tests, analysis of sperm DNA fragmentation and measurements of oxidative stress markers provide an independent measure of fertility in men with varicocele. These diagnostic modalities have both diagnostic and prognostic information complementary to, but distinct from conventional sperm parameters. Test results can guide management and aid in monitoring intervention outcomes. Proteomics, metabolomics, and genomics are areas; though still developing, holding promise to revolutionize our understanding of reproductive physiology, including varicocele. PMID:26780873
Ren, Jing; Chen, Liang; Jin, Xiaoli; Zhang, Miaomiao; You, Frank M; Wang, Jirui; Frenkel, Vladimir; Yin, Xuegui; Nevo, Eviatar; Sun, Dongfa; Luo, Ming-Cheng; Peng, Junhua
2017-01-01
Whole-genome scans with large number of genetic markers provide the opportunity to investigate local adaptation in natural populations and identify candidate genes under positive selection. In the present study, adaptation genetic differentiation associated with solar radiation was investigated using 695 polymorphic SNP markers in wild emmer wheat originated in a micro-site at Yehudiyya, Israel. The test involved two solar radiation niches: (1) sun, in-between trees; and (2) shade, under tree canopy, separated apart by a distance of 2-4 m. Analysis of molecular variance showed a small (0.53%) but significant portion of overall variation between the sun and shade micro-niches, indicating a non-ignorable genetic differentiation between sun and shade habitats. Fifty SNP markers showed a medium (0.05 ≤ F ST ≤ 0.15) or high genetic differentiation ( F ST > 0.15). A total of 21 outlier loci under positive selection were identified by using four different F ST -outlier testing algorithms. The markers and genome locations under positive selection are consistent with the known patterns of selection. These results suggested that genetic differentiation between sun and shade habitats is substantial, radiation-associated, and therefore ecologically determined. Hence, the results of this study reflected effects of natural selection through solar radiation on EST-related SNP genetic diversity, resulting presumably in different adaptive complexes at a micro-scale divergence. The present work highlights the evolutionary theory and application significance of solar radiation-driven natural selection in wheat improvement.
Hanevik, Kurt; Kristoffersen, Einar K; Sørnes, Steinar; Mørch, Kristine; Næss, Halvor; Rivenes, Ann C; Bødtker, Jørn E; Hausken, Trygve; Langeland, Nina
2012-10-14
A Giardia outbreak was associated with development of post-infectious functional gastrointestinal disorders (PI-FGID) and chronic fatigue syndrome (PI-CFS). Markers of immune dysfunction have given conflicting results in CFS and FGID patient populations. The aim of this study was to evaluate a wide selection of markers of immune dysfunction in these two co-occurring post-infectious syndromes. 48 patients, reporting chronic fatigue in a questionnaire study, were clinically evaluated five years after the outbreak and grouped according to Fukuda criteria for CFS (n=19) and idiopathic chronic fatigue (n=5) and Rome II criteria for FGIDs (n=54). 22 Giardia exposed non-fatigued individuals and 10 healthy unexposed individuals were recruited as controls. Peripheral blood lymphocyte subsets were analyzed by flow cytometry. In peripheral blood we found significantly higher CD8 T-cell levels in PI-FGID, and significantly lower NK-cell levels in PI-CFS patients. Severity of abdominal and fatigue symptoms correlated negatively with NK-cell levels. A tendency towards lower T-cell CD26 expression in FGID was seen. Patients with PI-CFS and/or PI-FGID 5 years after Giardia lamblia infection showed alterations in NK-cell and CD8-cell populations suggesting a possible immunological abnormality in these conditions. We found no significant changes in other markers examined in this well-defined group of PI-CFS and PI-FGID elicited by a gastrointestinal infection. Controlling for co-morbid conditions is important in evaluation of CFS-biomarkers.
Worska, Aneta; Piernicka, Magdalena; Kortas, Jakub; Jastrzębski, Zbigniew; Radzimiński, Łukasz; Jaworska, Joanna; Micielska, Katarzyna
2017-01-01
Background Both exercise and pregnancy influence serum irisin concentration. Aim To determine how the interaction of pregnancy and exercise affects irisin level and whether various patterns of exercise adherence had different effect on irisin concentration. Methods It was a one-group pretest-posttest study among 9 Caucasian nulliparous healthy women in normal pregnancy (age 23 ± 3 years, 21 ± 2 weeks of gestation; mean ± SD) who participated in 8-week group fitness program. Before and after exercise intervention, we determined serum concentrations of irisin and selected parameters of lipid profile and glucose homeostasis markers. Results In active women, irisin slightly decreased with the development of pregnancy. After 8 weeks of exercising, irisin correlated negatively with fasting glucose (R = −0.922; p = 0.001), glycated hemoglobin (R = −0.784; p = 0.012), and insulin concentrations (R = −0.845; p = 0.004). In women exercising below recommended level, we observed a significant drop in irisin concentration, whereas in women exercising at least three times a week this myokine slightly increased (31% difference; 90% confidence limits ±28; a large, clear effect). Conclusions Irisin stimulated by prenatal exercise may improve glucose homeostasis markers in healthy women and compensate for metabolic changes induced by pregnancy. Moreover, the frequency of exercise may regulate the changes in exercise-induced irisin concentration. PMID:29226153
Balancing Selection and Its Effects on Sequences in Nearby Genome Regions
Charlesworth, Deborah
2006-01-01
Our understanding of balancing selection is currently becoming greatly clarified by new sequence data being gathered from genes in which polymorphisms are known to be maintained by selection. The data can be interpreted in conjunction with results from population genetics models that include recombination between selected sites and nearby neutral marker variants. This understanding is making possible tests for balancing selection using molecular evolutionary approaches. Such tests do not necessarily require knowledge of the functional types of the different alleles at a locus, but such information, as well as information about the geographic distribution of alleles and markers near the genes, can potentially help towards understanding what form of balancing selection is acting, and how long alleles have been maintained. PMID:16683038
Elkot, Ahmed Fawzy Abdelnaby; Chhuneja, Parveen; Kaur, Satinder; Saluja, Manny; Keller, Beat; Singh, Kuldeep
2015-01-01
Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici, is one of the important wheat diseases, worldwide. Two PM resistance genes, designated as PmTb7A.1 and PmTb7A.2, were identified in T. boeoticum acc. pau5088 and mapped on chromosome 7AL approximately 48cM apart. Two resistance gene analogue (RGA)-STS markers Ta7AL-4556232 and 7AL-4426363 were identified to be linked to the PmTb7A.1 and PmTb7A.2, at a distance of 0.6cM and 6.0cM, respectively. In the present study, following marker assisted selection (MAS), the two genes were transferred to T. aestivum using T. durum as bridging species. As many as 12,317 florets of F1 of the cross T. durum /T. boeoticum were pollinated with T. aestivum lines PBW343-IL and PBW621 to produce 61 and 65 seeds, respectively, of three-way F1. The resulting F1s of the cross T. durum/T. boeoticum//T. aestivum were screened with marker flanking both the PM resistance genes PmTb7A.1 and PmTb7A.2 (foreground selection) and the selected plants were backcrossed to generate BC1F1. Marker assisted selection was carried both in BC1F1 and the BC2F1 generations. Introgression of alien chromatin in BC2F1 plants varied from 15.4-62.9 percent. Out of more than 110 BC2F1 plants showing introgression for markers linked to the two PM resistance genes, 40 agronomically desirable plants were selected for background selection for the carrier chromosome to identify the plants with minimum of the alien introgression. Cytological analysis showed that most plants have chromosome number ranging from 40-42. The BC2F2 plants homozygous for the two genes have been identified. These will be crossed to generate lines combining both the PM resistance genes but with minimal of the alien introgression. The PM resistance gene PmTb7A.1 maps in a region very close to Sr22, a stem rust resistance gene effective against the race Ug99. Analysis of selected plants with markers linked to Sr22 showed introgression of Sr22 from T. boeoticum in several BC2F1 plants. Thus, in addition to PM resistance, these progeny might also carry resistance to stem rust race Ug99.
Green, Sophie; Lambon Ralph, Matthew A; Moll, Jorge; Deakin, John F W; Zahn, Roland
2012-10-01
Proneness to overgeneralization of self-blame is a core part of cognitive vulnerability to major depressive disorder (MDD) and remains dormant after remission of symptoms. Current neuroanatomical models of MDD, however, assume general increases of negative emotions and are unable to explain biases toward emotions entailing self-blame (eg, guilt) relative to those associated with blaming others (eg, indignation). Recent functional magnetic resonance imaging (fMRI) studies in healthy participants have shown that moral feelings such as guilt activate representations of social meaning within the right superior anterior temporal lobe (ATL). Furthermore, this area was selectively coupled with the subgenual cingulate cortex and adjacent septal region (SCSR) during the experience of guilt compared with indignation. Despite its psychopathological importance, the functional neuroanatomy of guilt in MDD is unknown. To use fMRI to test the hypothesis that, in comparison with control individuals, participants with remitted MDD exhibit guilt-selective SCSR-ATL decoupling as a marker of deficient functional integration. Case-control study from May 1, 2008, to June 1, 2010. Clinical research facility. Twenty-five patients with remitted MDD (no medication in 16 patients) with no current comorbid Axis I disorders and 22 controls with no personal or family history of MDD. Between-group difference of ATL coupling with a priori SCSR region of interest for guilt vs indignation. We corroborated the prediction of a guilt-selective reduction in ATL-SCSR coupling in MDD vs controls (familywise error-corrected P=.001 over the region of interest) and revealed additional medial frontopolar, right hippocampal, and lateral hypothalamic areas of decoupling while controlling for medication status and intensity of negative emotions. Lower levels of ATL-SCSR coupling were associated with higher scores on a validated measure of overgeneralized self-blame (67-item Interpersonal Guilt Questionnaire). Vulnerability to MDD is associated with temporofrontolimbic decoupling that is selective for self-blaming feelings. This provides the first neural mechanism ofMDD vulnerability that accounts for self-blaming biases.
NASA Astrophysics Data System (ADS)
Karfa, Paramita; Madhuri, Rashmi; Sharma, Prashant K.
2017-05-01
In this work, a sensitive and selective fluorescent molecularly imprinted polymer (MIP) was developed for detection of hepatocellular carcinoma (HCC) biomarker i.e. alpha feto protein (AFP) using Ag/AgCl as platform. Here, the carbon dots and Ag/AgCl nanoparticles were functionalized with vinyl groups and used as functional monomer for synthesis of AFP-imprinted polymer. The imprinted polymer shows a linear range of 3.96 ng mL-1 to 80.0 ng mL-1 with detection limit of 0.42 ng mL-1.The adsorption property of the MIP@Ag/AgCl was studied and shows the high affinity binding towards their target analyte without any cross-reactivity and false-positive or false-negative results.
The GCP molecular marker toolkit, an instrument for use in breeding food security crops.
Van Damme, Veerle; Gómez-Paniagua, Humberto; de Vicente, M Carmen
2011-12-01
Crop genetic resources carry variation useful for overcoming the challenges of modern agriculture. Molecular markers can facilitate the selection of agronomically important traits. The pervasiveness of genomics research has led to an overwhelming number of publications and databases, which are, nevertheless, scattered and hence often difficult for plant breeders to access, particularly those in developing countries. This situation separates them from developed countries, which have better endowed programs for developing varieties. To close this growing knowledge gap, we conducted an intensive literature review and consulted with more than 150 crop experts on the use of molecular markers in the breeding program of 19 food security crops. The result was a list of effectively used and highly reproducible sequence tagged site (STS), simple sequence repeat (SSR), single nucleotide polymorphism (SNP), and sequence characterized amplified region (SCAR) markers. However, only 12 food crops had molecular markers suitable for improvement. That is, marker-assisted selection is not yet used for Musa spp., coconut, lentils, millets, pigeonpea, sweet potato, and yam. For the other 12 crops, 214 molecular markers were found to be effectively used in association with 74 different traits. Results were compiled as the GCP Molecular Marker Toolkit, a free online tool that aims to promote the adoption of molecular approaches in breeding activities.
[Prognostic and predictive molecular markers for urologic cancers].
Hartmann, A; Schlomm, T; Bertz, S; Heinzelmann, J; Hölters, S; Simon, R; Stoehr, R; Junker, K
2014-04-01
Molecular prognostic factors and genetic alterations as predictive markers for cancer-specific targeted therapies are used today in the clinic for many malignancies. In recent years, many molecular markers for urogenital cancers have also been identified. However, these markers are not clinically used yet. In prostate cancer, novel next-generation sequencing methods revealed a detailed picture of the molecular changes. There is growing evidence that a combination of classical histopathological and validated molecular markers could lead to a more precise estimation of prognosis, thus, resulting in an increasing number of patients with active surveillance as a possible treatment option. In patients with urothelial carcinoma, histopathological factors but also the proliferation of the tumor, mutations in oncogenes leading to an increasing proliferation rate and changes in genes responsible for invasion and metastasis are important. In addition, gene expression profiles which could distinguish aggressive tumors with high risk of metastasis from nonmetastasizing tumors have been recently identified. In the future, this could potentially allow better selection of patients needing systemic perioperative treatment. In renal cell carcinoma, many molecular markers that are associated with metastasis and survival have been identified. Some of these markers were also validated as independent prognostic markers. Selection of patients with primarily organ-confined tumors and increased risk of metastasis for adjuvant systemic therapy could be clinically relevant in the future.
Bhawna; Chaduvula, Pavan K; Bonthala, Venkata S; Manjusha, Verma; Siddiq, Ebrahimali A; Polumetla, Ananda K; Prasad, Gajula M N V
2015-01-01
Cucumis melo L. that belongs to Cucurbitaceae family ranks among one of the highest valued horticulture crops being cultivated across the globe. Besides its economical and medicinal importance, Cucumis melo L. is a valuable resource and model system for the evolutionary studies of cucurbit family. However, very limited numbers of molecular markers were reported for Cucumis melo L. so far that limits the pace of functional genomic research in melon and other similar horticulture crops. We developed the first whole genome based microsatellite DNA marker database of Cucumis melo L. and comprehensive web resource that aids in variety identification and physical mapping of Cucurbitaceae family. The Cucumis melo L. microsatellite database (CmMDb: http://65.181.125.102/cmmdb2/index.html) encompasses 39,072 SSR markers along with its motif repeat, motif length, motif sequence, marker ID, motif type and chromosomal locations. The database is featured with novel automated primer designing facility to meet the needs of wet lab researchers. CmMDb is a freely available web resource that facilitates the researchers to select the most appropriate markers for marker-assisted selection in melons and to improve breeding strategies.
Liabeuf, Debora; Sim, Sung-Chur; Francis, David M
2018-03-01
Bacterial spot affects tomato crops (Solanum lycopersicum) grown under humid conditions. Major genes and quantitative trait loci (QTL) for resistance have been described, and multiple loci from diverse sources need to be combined to improve disease control. We investigated genomic selection (GS) prediction models for resistance to Xanthomonas euvesicatoria and experimentally evaluated the accuracy of these models. The training population consisted of 109 families combining resistance from four sources and directionally selected from a population of 1,100 individuals. The families were evaluated on a plot basis in replicated inoculated trials and genotyped with single nucleotide polymorphisms (SNP). We compared the prediction ability of models developed with 14 to 387 SNP. Genomic estimated breeding values (GEBV) were derived using Bayesian least absolute shrinkage and selection operator regression (BL) and ridge regression (RR). Evaluations were based on leave-one-out cross validation and on empirical observations in replicated field trials using the next generation of inbred progeny and a hybrid population resulting from selections in the training population. Prediction ability was evaluated based on correlations between GEBV and phenotypes (r g ), percentage of coselection between genomic and phenotypic selection, and relative efficiency of selection (r g /r p ). Results were similar with BL and RR models. Models using only markers previously identified as significantly associated with resistance but weighted based on GEBV and mixed models with markers associated with resistance treated as fixed effects and markers distributed in the genome treated as random effects offered greater accuracy and a high percentage of coselection. The accuracy of these models to predict the performance of progeny and hybrids exceeded the accuracy of phenotypic selection.
Negative Emotions and Behaviors are Markers of Breakup Distress
ERIC Educational Resources Information Center
Field, Tiffany; Diego, Miguel; Pelaez, Martha; Deeds, Osvelia; Delgado, Jeanette
2013-01-01
Method: University students who experienced a recent romantic breakup were given several self-report measures and were then divided into high versus low breakup distress groups. Results: The high breakup distress versus the low breakup distress groups had higher scores on negative emotions scales including depression, anxiety and anger and…
Zapata, Luis; Pich, Oriol; Serrano, Luis; Kondrashov, Fyodor A; Ossowski, Stephan; Schaefer, Martin H
2018-05-31
Natural selection shapes cancer genomes. Previous studies used signatures of positive selection to identify genes driving malignant transformation. However, the contribution of negative selection against somatic mutations that affect essential tumor functions or specific domains remains a controversial topic. Here, we analyze 7546 individual exomes from 26 tumor types from TCGA data to explore the portion of the cancer exome under negative selection. Although we find most of the genes neutrally evolving in a pan-cancer framework, we identify essential cancer genes and immune-exposed protein regions under significant negative selection. Moreover, our simulations suggest that the amount of negative selection is underestimated. We therefore choose an empirical approach to identify genes, functions, and protein regions under negative selection. We find that expression and mutation status of negatively selected genes is indicative of patient survival. Processes that are most strongly conserved are those that play fundamental cellular roles such as protein synthesis, glucose metabolism, and molecular transport. Intriguingly, we observe strong signals of selection in the immunopeptidome and proteins controlling peptide exposition, highlighting the importance of immune surveillance evasion. Additionally, tumor type-specific immune activity correlates with the strength of negative selection on human epitopes. In summary, our results show that negative selection is a hallmark of cell essentiality and immune response in cancer. The functional domains identified could be exploited therapeutically, ultimately allowing for the development of novel cancer treatments.
Smith, Nathaniel E; Illei, Peter B; Allaf, Mohamed; Gonzalez, Nilda; Morris, Kerry; Hicks, Jessica; Demarzo, Angelo; Reuter, Victor E; Amin, Mahul B; Epstein, Jonathan I; Netto, George J; Argani, Pedram
2014-05-01
Renal cell carcinomas (RCCs) harboring the t(6;11)(p21;q12) translocation were first described in 2001 and recently recognized by the 2013 International Society of Urological Pathology Vancouver Classification of Renal Neoplasia. Although these RCCs are known to label for melanocytic markers HMB45 and Melan A and the cysteine protease cathepsin K by immunohistochemistry (IHC), a comprehensive IHC profile has not been reported. We report 10 new t(6;11) RCCs, all confirmed by break-apart TFEB fluorescence in situ hybridization. A tissue microarray containing 6 of these cases and 7 other previously reported t(6;11) RCCs was constructed and immunolabeled for 21 different antigens. Additional whole sections of t(6;11) RCC were labeled with selected IHC markers. t(6;11) RCC labeled diffusely and consistently for cathepsin K and Melan A (13 of 13 cases) and almost always at least focally for HMB45 (12 of 13 cases). They labeled frequently for PAX8 (14 of 23 cases), CD117 (10 of 14 cases), and vimentin (9 of 13 cases). A majority of cases labeled at least focally for cytokeratin Cam5.2 (8 of 13 cases) and CD10 and RCC marker antigen (10 of 14 cases each). In contrast to a prior study's findings, only a minority of cases labeled for Ksp-cadherin (3 of 19 cases). The median H score (product of intensity score and percentage labeling) for phosphorylated S6, a marker of mTOR pathway activation, was 101, which is high relative to most other RCC subtypes. In summary, IHC labeling for PAX8, Cam5.2, CD10, and RCC marker antigen supports classification of the t(6;11) RCC as carcinomas despite frequent negativity for broad-spectrum cytokeratins and EMA. Labeling for PAX8 distinguishes the t(6;11) RCC from epithelioid angiomyolipoma, which otherwise shares a similar immunoprofile. CD117 labeling is more frequent in the t(6;11) RCC compared with the related Xp11 translocation RCC. Increased pS6 expression suggests a possible molecular target for the uncommon t(6;11) RCCs that metastasize.
USDA-ARS?s Scientific Manuscript database
Selection of the composite MARC III population for markers allowed better estimates of effects and inheritance of markers for targeted carcass quality traits (n=254) and nontargeted traits and an evaluation of SNP specific residual variance models for tenderness. Genotypic effects of CAPN1 haplotyp...
Rajter, Ľubomír; Vďačný, Peter
2018-05-12
The class Litostomatea represents a highly diverse but monophyletic group, uniting both free-living and endosymbiotic ciliates. Ribosomal RNA genes and ITS-region sequences helped to recognize and define the main litostomatean lineages, but did not provide enough phylogenetic signal to unambiguously resolve their interrelationships. In this study, we attempted to improve the resolution among main free-living predatory lineages by adding the gene coding for alpha-tubulin. However, our phylogenetic analyses challenged the performance of alpha-tubulin in reconstruction of evolutionary history of free-living litostomateans. We identified several mutually interconnected problems associated with the ciliate alpha-tubulin gene: the paucity of phylogenetic signal, molecular homoplasies and non-neutral evolution. Positive selection may generate molecular homoplasies (parallel evolution), while negative selection may cause a small number of changes and hence little phylogenetic informativness. Both problems were encountered in nucleotide and amino acid alpha-tubulin alignments, indicating an action of various selective pressures. Taking into account the involvement of alpha-tubulin in many essential biological processes, this protein could be so strongly affected by purifying selection that it even might have become an inappropriate molecular marker for reconstruction of phylogenetic relationships. Therefore, a great caution should be paid when tubulin genes are included in phylogenetic and/or phylogenomic analyses. Copyright © 2018 Elsevier Inc. All rights reserved.
Identification of body fluid-specific DNA methylation markers for use in forensic science.
Park, Jong-Lyul; Kwon, Oh-Hyung; Kim, Jong Hwan; Yoo, Hyang-Sook; Lee, Han-Chul; Woo, Kwang-Man; Kim, Seon-Young; Lee, Seung-Hwan; Kim, Yong Sung
2014-11-01
DNA methylation, which occurs at the 5'-position of the cytosine in CpG dinucleotides, has great potential for forensic identification of body fluids, because tissue-specific patterns of DNA methylation have been demonstrated, and DNA is less prone to degradation than proteins or RNA. Previous studies have reported several body fluid-specific DNA methylation markers, but DNA methylation differences are sometimes low in saliva and vaginal secretions. Moreover, specific DNA methylation markers in four types of body fluids (blood, saliva, semen, and vaginal secretions) have not been investigated with genome-wide profiling. Here, we investigated novel DNA methylation markers for identification of body fluids for use in forensic science using the Illumina HumanMethylation 450K bead array, which contains over 450,000 CpG sites. Using methylome data from 16 samples of blood, saliva, semen, and vaginal secretions, we first selected 2986 hypermethylated or hypomethylated regions that were specific for each type of body fluid. We then selected eight CpG sites as novel, forensically relevant DNA methylation markers: cg06379435 and cg08792630 for blood, cg26107890 and cg20691722 for saliva, cg23521140 and cg17610929 for semen, and cg01774894 and cg14991487 for vaginal secretions. These eight selected markers were evaluated in 80 body fluid samples using pyrosequencing, and all showed high sensitivity and specificity for identification of the target body fluid. We suggest that these eight DNA methylation markers may be good candidates for developing an effective molecular assay for identification of body fluids in forensic science. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
2012-01-01
Background In the last 30 years, a number of DNA fingerprinting methods such as RFLP, RAPD, AFLP, SSR, DArT, have been extensively used in marker development for molecular plant breeding. However, it remains a daunting task to identify highly polymorphic and closely linked molecular markers for a target trait for molecular marker-assisted selection. The next-generation sequencing (NGS) technology is far more powerful than any existing generic DNA fingerprinting methods in generating DNA markers. In this study, we employed a grain legume crop Lupinus angustifolius (lupin) as a test case, and examined the utility of an NGS-based method of RAD (restriction-site associated DNA) sequencing as DNA fingerprinting for rapid, cost-effective marker development tagging a disease resistance gene for molecular breeding. Results Twenty informative plants from a cross of RxS (disease resistant x susceptible) in lupin were subjected to RAD single-end sequencing by multiplex identifiers. The entire RAD sequencing products were resolved in two lanes of the 16-lanes per run sequencing platform Solexa HiSeq2000. A total of 185 million raw reads, approximately 17 Gb of sequencing data, were collected. Sequence comparison among the 20 test plants discovered 8207 SNP markers. Filtration of DNA sequencing data with marker identification parameters resulted in the discovery of 38 molecular markers linked to the disease resistance gene Lanr1. Five randomly selected markers were converted into cost-effective, simple PCR-based markers. Linkage analysis using marker genotyping data and disease resistance phenotyping data on a F8 population consisting of 186 individual plants confirmed that all these five markers were linked to the R gene. Two of these newly developed sequence-specific PCR markers, AnSeq3 and AnSeq4, flanked the target R gene at a genetic distance of 0.9 centiMorgan (cM), and are now replacing the markers previously developed by a traditional DNA fingerprinting method for marker-assisted selection in the Australian national lupin breeding program. Conclusions We demonstrated that more than 30 molecular markers linked to a target gene of agronomic trait of interest can be identified from a small portion (1/8) of one sequencing run on HiSeq2000 by applying NGS based RAD sequencing in marker development. The markers developed by the strategy described in this study are all co-dominant SNP markers, which can readily be converted into high throughput multiplex format or low-cost, simple PCR-based markers desirable for large scale marker implementation in plant breeding programs. The high density and closely linked molecular markers associated with a target trait help to overcome a major bottleneck for implementation of molecular markers on a wide range of germplasm in breeding programs. We conclude that application of NGS based RAD sequencing as DNA fingerprinting is a very rapid and cost-effective strategy for marker development in molecular plant breeding. The strategy does not require any prior genome knowledge or molecular information for the species under investigation, and it is applicable to other plant species. PMID:22805587
Yang, Huaan; Tao, Ye; Zheng, Zequn; Li, Chengdao; Sweetingham, Mark W; Howieson, John G
2012-07-17
In the last 30 years, a number of DNA fingerprinting methods such as RFLP, RAPD, AFLP, SSR, DArT, have been extensively used in marker development for molecular plant breeding. However, it remains a daunting task to identify highly polymorphic and closely linked molecular markers for a target trait for molecular marker-assisted selection. The next-generation sequencing (NGS) technology is far more powerful than any existing generic DNA fingerprinting methods in generating DNA markers. In this study, we employed a grain legume crop Lupinus angustifolius (lupin) as a test case, and examined the utility of an NGS-based method of RAD (restriction-site associated DNA) sequencing as DNA fingerprinting for rapid, cost-effective marker development tagging a disease resistance gene for molecular breeding. Twenty informative plants from a cross of RxS (disease resistant x susceptible) in lupin were subjected to RAD single-end sequencing by multiplex identifiers. The entire RAD sequencing products were resolved in two lanes of the 16-lanes per run sequencing platform Solexa HiSeq2000. A total of 185 million raw reads, approximately 17 Gb of sequencing data, were collected. Sequence comparison among the 20 test plants discovered 8207 SNP markers. Filtration of DNA sequencing data with marker identification parameters resulted in the discovery of 38 molecular markers linked to the disease resistance gene Lanr1. Five randomly selected markers were converted into cost-effective, simple PCR-based markers. Linkage analysis using marker genotyping data and disease resistance phenotyping data on a F8 population consisting of 186 individual plants confirmed that all these five markers were linked to the R gene. Two of these newly developed sequence-specific PCR markers, AnSeq3 and AnSeq4, flanked the target R gene at a genetic distance of 0.9 centiMorgan (cM), and are now replacing the markers previously developed by a traditional DNA fingerprinting method for marker-assisted selection in the Australian national lupin breeding program. We demonstrated that more than 30 molecular markers linked to a target gene of agronomic trait of interest can be identified from a small portion (1/8) of one sequencing run on HiSeq2000 by applying NGS based RAD sequencing in marker development. The markers developed by the strategy described in this study are all co-dominant SNP markers, which can readily be converted into high throughput multiplex format or low-cost, simple PCR-based markers desirable for large scale marker implementation in plant breeding programs. The high density and closely linked molecular markers associated with a target trait help to overcome a major bottleneck for implementation of molecular markers on a wide range of germplasm in breeding programs. We conclude that application of NGS based RAD sequencing as DNA fingerprinting is a very rapid and cost-effective strategy for marker development in molecular plant breeding. The strategy does not require any prior genome knowledge or molecular information for the species under investigation, and it is applicable to other plant species.
ERIC Educational Resources Information Center
Wispe, Lauren G.
This paper describes a study of the relationship between terminology in psychological studies and prevailing social conditions at the time of the studies. It is proposed that researchers reflect societal concerns by their choice of semantic markers (terminology). Over 3,000 psychological studies from 1900-72 were analyzed in terms of their…
USDA-ARS?s Scientific Manuscript database
Molecular markers are useful for the identification of critical genes controlling agricultural traits of interest in crop germplasm and for the utilization of these genes in crop improvement using marker assisted selection (MAS). The improvement of blast disease resistance of rice varieties is one o...
Annette M. Kretzer; Susie Dunham; Randy Molina; Joseph W. Spatafora
2003-01-01
We have developed microsatellite markers for two sister species of Rhizopogon, R. vesiculosus and R. vinicolor (Boletales, Basidiomycota), and used selected markers to investigate genet size and distribution from ectomycorrhizal samples. Both species form ectomycorrhizas with tuberculate morphology on Douglas-fir (...
Genome wide association study (GWAS) for grain yield in rice cultivated under water deficit.
Pantalião, Gabriel Feresin; Narciso, Marcelo; Guimarães, Cléber; Castro, Adriano; Colombari, José Manoel; Breseghello, Flavio; Rodrigues, Luana; Vianello, Rosana Pereira; Borba, Tereza Oliveira; Brondani, Claudio
2016-12-01
The identification of rice drought tolerant materials is crucial for the development of best performing cultivars for the upland cultivation system. This study aimed to identify markers and candidate genes associated with drought tolerance by Genome Wide Association Study analysis, in order to develop tools for use in rice breeding programs. This analysis was made with 175 upland rice accessions (Oryza sativa), evaluated in experiments with and without water restriction, and 150,325 SNPs. Thirteen SNP markers associated with yield under drought conditions were identified. Through stepwise regression analysis, eight SNP markers were selected and validated in silico, and when tested by PCR, two out of the eight SNP markers were able to identify a group of rice genotypes with higher productivity under drought. These results are encouraging for deriving markers for the routine analysis of marker assisted selection. From the drought experiment, including the genes inherited in linkage blocks, 50 genes were identified, from which 30 were annotated, and 10 were previously related to drought and/or abiotic stress tolerance, such as the transcription factors WRKY and Apetala2, and protein kinases.
Guillaume, François; Fritz, Sébastien; Boichard, Didier; Druet, Tom
2008-01-01
The efficiency of the French marker-assisted selection (MAS) was estimated by a simulation study. The data files of two different time periods were used: April 2004 and 2006. The simulation method used the structure of the existing French MAS: same pedigree, same marker genotypes and same animals with records. The program simulated breeding values and new records based on this existing structure and knowledge on the QTL used in MAS (variance and frequency). Reliabilities of genetic values of young animals (less than one year old) obtained with and without marker information were compared to assess the efficiency of MAS for evaluation of milk, fat and protein yields and fat and protein contents. Mean gains of reliability ranged from 0.015 to 0.094 and from 0.038 to 0.114 in 2004 and 2006, respectively. The larger number of animals genotyped and the use of a new set of genetic markers can explain the improvement of MAS reliability from 2004 to 2006. This improvement was also observed by analysis of information content for young candidates. The gain of MAS reliability with respect to classical selection was larger for sons of sires with genotyped progeny daughters with records. Finally, it was shown that when superiority of MAS over classical selection was estimated with daughter yield deviations obtained after progeny test instead of true breeding values, the gain was underestimated. PMID:18096117
Biological markers of melancholia and reclassification of depressive disorders.
Greden, J F
1982-01-01
Pathophysiological markers of melancholia are being developed in four major areas: 1) neuroendocrine; 2) sleep; 3) psychomotor and 4) biochemical. Neuroendocrine markers include a failure of suppress plasma cortisol secretion in the dexamethasone suppression test (DST), diminished thyrotrophin (TSH) response to thyrotrophin releasing hormone (TRH stimulation test), and blunted growth hormone response to a variety of stimulating agents such as d-amphetamine, methylamphetamine, clonidine, L-dopa and insulin (growth hormone test). Of these, the DST is the best standardized. It is a highly specific laboratory marker with documented value in diagnosis, assessing prognosis and monitoring treatment progress. Sleep EEG abnormalities include reduced REM latency, increased REM density, reduction in delta sleep and impaired sleep efficiency. Sleep EEGs are pragmatically difficult, but results are quite specific. Elongated speech pause time (SPT) during "automatic speech" is a promising marker of psychomotor regulation. This simple, non-invasive measure may have special value in reducing clinical subjectivity and in monitoring treatment progress. Biochemical markers include: 1) platelet monoamine oxidase (MAO) activity; 2) in vitro lithium RBC transport and 3) urinary MHPG levels. Standardizations of biochemical tests are still lacking. Most biological tests for melancholia operate by indirectly "marking" CNS limbic system dysfunction. For wide acceptance, a test must be safe, moderately sensitive, highly specific, practical, relatively inexpensive and not significantly altered by common anti-depressant treatments. The DST best meets these criteria at this time. Proper utilization of test results requires knowledge of baseline prevalence rates and of the concepts of sensitivity (true-positive rate), specificity (true negative rate) and positive and negative predictive values (diagnostic confidence). No single marker will meet all clinical needs. Combinations or serial use of tests will hopefully enhance their already considerable usefulness.
Bekele, Berhanu D; Naveen, G K; Rakhi, S; Shashidhar, H E
2013-12-01
The objectives of the present study were to evaluate genetic variability parameters, correlations that exist for grain Zn concentration and yield related traits and identification of SSR markers linked to these traits in rice. One hundred seventy six Recombinant Inbred Lines (RILs) of Azucena X Moromutant were grown at University of Agricultural Sciences, Bangalore in augmented experimental design during wet seasons of 2010 and 2011. The study revealed significant genetic variability for all the traits. Grain yield per plant and grain zinc concentration showed higher phenotypic and genotypic co-efficient of variation. Significant positive correlation was observed for grain yield per plant with number of productive tillers per plant (r = 0.5) and number of tillers per plant (r = 0.4). Grain zinc concentration showed negative correlation with grain yield per plant (r = - 0.27). The path-coefficient analysis indicated the positive direct effect of number of productive tillers per plant on grain yield per plant (0.514). Grain zinc concentration showed negative direct effect on grain yield per plant (-0.186). Single-marker analysis using 26 SSR markers on RILs mapping population showed that RM212, RM263, RM6832, RM152, RM21, RM234 and RM3331 had association with grain zinc concentration and other yield related traits. But validation of these markers on fifty two rice genotypes showed that only three markers RM263, RM152 and RM21 had association with grain zinc concentration. Therefore, the genetic information generated and molecular markers identified from this study could be used for zinc biofortification programmes in rice.
Garnache-Ottou, Francine; Chaperot, Laurence; Biichle, Sabeha; Ferrand, Christophe; Remy-Martin, Jean-Paul; Deconinck, Eric; de Tailly, Patrick Darodes; Bulabois, Bénédicte; Poulet, Jacqueline; Kuhlein, Emilienne; Jacob, Marie-Christine; Salaun, Véronique; Arock, Michel; Drenou, Bernard; Schillinger, Françoise; Seilles, Estelle; Tiberghien, Pierre; Bensa, Jean-Claude; Plumas, Joel; Saas, Philippe
2005-02-01
A new entity of acute leukemia coexpressing CD4(+)CD56(+) markers without any other lineage-specific markers has been identified recently as arising from lymphoid-related plasmacytoid dendritic cells (pDCs). In our laboratory, cells from a patient with such CD4(+)CD56(+) lineage-negative leukemia were unexpectedly found to also express the myeloid marker CD33. To confirm the diagnosis of pDC leukemia despite the CD33 expression, we demonstrated that the leukemic cells indeed exhibited pDC phenotypic and functional properties. In 7 of 8 other patients with CD4(+)CD56(+) pDC malignancies, we were able to confirm that the tumor cells expressed CD33 although with variable expression levels. CD33 expression was shown by flow cytometry, reverse transcriptase-polymerase chain reaction, and immunoblot analysis. Furthermore, CD33 monoclonal antibody stimulation of purified CD4(+)CD56(+) leukemic cells led to cytokine secretion, thus confirming the presence of a functional CD33 on these leukemic cells. Moreover, we found that circulating pDCs in healthy individuals also weakly express CD33. Overall, our results demonstrate that the expression of CD33 on CD4(+)CD56(+) lineage-negative cells should not exclude the diagnosis of pDC leukemia and underline that pDC-specific markers should be used at diagnosis for CD4(+)CD56(+) malignancies.
Neural correlates of uncertain decision making: ERP evidence from the Iowa Gambling Task
Cui, Ji-fang; Chen, Ying-he; Wang, Ya; Shum, David H. K.; Chan, Raymond C. K.
2013-01-01
In our daily life, it is very common to make decisions in uncertain situations. The Iowa Gambling Task (IGT) has been widely used in laboratory studies because of its good simulation of uncertainty in real life activities. The present study aimed to examine the neural correlates of uncertain decision making with the IGT. Twenty-six university students completed this study. An adapted IGT was administered to them, and the EEG data were recorded. The adapted IGT we used allowed us to analyze the choice evaluation, response selection, and feedback evaluation stages of uncertain decision making within the same paradigm. In the choice evaluation stage, the advantageous decks evoked larger P3 amplitude in the left hemisphere, while the disadvantageous decks evoked larger P3 in the right hemisphere. In the response selection stage, the response of “pass” (the card was not turned over; the participants neither won nor lost money) evoked larger negativity preceding the response compared to that of “play” (the card was turned over; the participant either won or lost money). In the feedback evaluation stage, feedback-related negativity (FRN) was only sensitive to the valence (win/loss) but not the magnitude (large/small) of the outcome, and P3 was sensitive to both the valence and the magnitude of the outcome. These results were consistent with the notion that a positive somatic state was represented in the left hemisphere and a negative somatic state was represented in the right hemisphere. There were also anticipatory ERP effects that guided the participants' responses and provided evidence for the somatic marker hypothesis with more precise timing. PMID:24298248
Stochastic dynamics of adaptive trait and neutral marker driven by eco-evolutionary feedbacks.
Billiard, Sylvain; Ferrière, Régis; Méléard, Sylvie; Tran, Viet Chi
2015-11-01
How the neutral diversity is affected by selection and adaptation is investigated in an eco-evolutionary framework. In our model, we study a finite population in continuous time, where each individual is characterized by a trait under selection and a completely linked neutral marker. Population dynamics are driven by births and deaths, mutations at birth, and competition between individuals. Trait values influence ecological processes (demographic events, competition), and competition generates selection on trait variation, thus closing the eco-evolutionary feedback loop. The demographic effects of the trait are also expected to influence the generation and maintenance of neutral variation. We consider a large population limit with rare mutation, under the assumption that the neutral marker mutates faster than the trait under selection. We prove the convergence of the stochastic individual-based process to a new measure-valued diffusive process with jumps that we call Substitution Fleming-Viot Process (SFVP). When restricted to the trait space this process is the Trait Substitution Sequence first introduced by Metz et al. (1996). During the invasion of a favorable mutation, a genetical bottleneck occurs and the marker associated with this favorable mutant is hitchhiked. By rigorously analysing the hitchhiking effect and how the neutral diversity is restored afterwards, we obtain the condition for a time-scale separation; under this condition, we show that the marker distribution is approximated by a Fleming-Viot distribution between two trait substitutions. We discuss the implications of the SFVP for our understanding of the dynamics of neutral variation under eco-evolutionary feedbacks and illustrate the main phenomena with simulations. Our results highlight the joint importance of mutations, ecological parameters, and trait values in the restoration of neutral diversity after a selective sweep.
Kavakiotis, Ioannis; Samaras, Patroklos; Triantafyllidis, Alexandros; Vlahavas, Ioannis
2017-11-01
Single Nucleotide Polymorphism (SNPs) are, nowadays, becoming the marker of choice for biological analyses involving a wide range of applications with great medical, biological, economic and environmental interest. Classification tasks i.e. the assignment of individuals to groups of origin based on their (multi-locus) genotypes, are performed in many fields such as forensic investigations, discrimination between wild and/or farmed populations and others. Τhese tasks, should be performed with a small number of loci, for computational as well as biological reasons. Thus, feature selection should precede classification tasks, especially for Single Nucleotide Polymorphism (SNP) datasets, where the number of features can amount to hundreds of thousands or millions. In this paper, we present a novel data mining approach, called FIFS - Frequent Item Feature Selection, based on the use of frequent items for selection of the most informative markers from population genomic data. It is a modular method, consisting of two main components. The first one identifies the most frequent and unique genotypes for each sampled population. The second one selects the most appropriate among them, in order to create the informative SNP subsets to be returned. The proposed method (FIFS) was tested on a real dataset, which comprised of a comprehensive coverage of pig breed types present in Britain. This dataset consisted of 446 individuals divided in 14 sub-populations, genotyped at 59,436 SNPs. Our method outperforms the state-of-the-art and baseline methods in every case. More specifically, our method surpassed the assignment accuracy threshold of 95% needing only half the number of SNPs selected by other methods (FIFS: 28 SNPs, Delta: 70 SNPs Pairwise FST: 70 SNPs, In: 100 SNPs.) CONCLUSION: Our approach successfully deals with the problem of informative marker selection in high dimensional genomic datasets. It offers better results compared to existing approaches and can aid biologists in selecting the most informative markers with maximum discrimination power for optimization of cost-effective panels with applications related to e.g. species identification, wildlife management, and forensics. Copyright © 2017 Elsevier Ltd. All rights reserved.
Yu, Guotai; Zhang, Qijun; Friesen, Timothy L; Rouse, Matthew N; Jin, Yue; Zhong, Shaobin; Rasmussen, Jack B; Lagudah, Evans S; Xu, Steven S
2015-03-01
Mapping studies confirm that resistance to Ug99 race of stem rust pathogen in Aegilops tauschii accession Clae 25 is conditioned by Sr46 and markers linked to the gene were developed for marker-assisted selection. The race TTKSK (Ug99) of Puccinia graminis f. sp. tritici, the causal pathogen for wheat stem rust, is considered as a major threat to global wheat production. To address this threat, researchers across the world have been devoted to identifying TTKSK-resistant genes. Here, we report the identification and mapping of a stem rust resistance gene in Aegilops tauschii accession CIae 25 that confers resistance to TTKSK and the development of molecular markers for the gene. An F2 population of 710 plants from an Ae. tauschii cross CIae 25 × AL8/78 were first evaluated against race TPMKC. A set of 14 resistant and 116 susceptible F2:3 families from the F2 plants were then evaluated for their reactions to TTKSK. Based on the tests, 179 homozygous susceptible F2 plants were selected as the mapping population to identify the simple sequence repeat (SSR) and sequence tagged site (STS) markers linked to the gene by bulk segregant analysis. A dominant stem rust resistance gene was identified and mapped with 16 SSR and five new STS markers to the deletion bin 2DS5-0.47-1.00 of chromosome arm 2DS in which Sr46 was located. Molecular marker and stem rust tests on CIae 25 and two Ae. tauschii accessions carrying Sr46 confirmed that the gene in CIae 25 is Sr46. This study also demonstrated that Sr46 is temperature-sensitive being less effective at low temperatures. The marker validation indicated that two closely linked markers Xgwm210 and Xwmc111 can be used for marker-assisted selection of Sr46 in wheat breeding programs.
Urrestarazu, Jorge; Royo, José B.; Santesteban, Luis G.; Miranda, Carlos
2015-01-01
Fingerprinting information can be used to elucidate in a robust manner the genetic structure of germplasm collections, allowing a more rational and fine assessment of genetic resources. Bayesian model-based approaches are nowadays majorly preferred to infer genetic structure, but it is still largely unresolved how marker sets should be built in order to obtain a robust inference. The objective was to evaluate, in Pyrus germplasm collections, the influence of the SSR marker set size on the genetic structure inferred, also evaluating the influence of the criterion used to select those markers. Inferences were performed considering an increasing number of SSR markers that ranged from just two up to 25, incorporated one at a time into the analysis. The influence of the number of SSR markers used was evaluated comparing the number of populations and the strength of the signal detected, and also the similarity of the genotype assignments to populations between analyses. In order to test if those results were influenced by the criterion used to select the SSRs, several choosing scenarios based on the discrimination power or the fixation index values of the SSRs were tested. Our results indicate that population structure could be inferred accurately once a certain SSR number threshold was reached, which depended on the underlying structure within the genotypes, but the method used to select the markers included on each set appeared not to be very relevant. The minimum number of SSRs required to provide robust structure inferences and adequate measurements of the differentiation, even when low differentiation levels exist within populations, was proved similar to that of the complete list of recommended markers for fingerprinting. When a SSR set size similar to the minimum marker sets recommended for fingerprinting it is used, only major divisions or moderate (F ST>0.05) differentiation of the germplasm are detected. PMID:26382618
Hayford, Maria B.; Medford, June I.; Hoffman, Nancy L.; Rogers, Stephen G.; Klee, Harry J.
1988-01-01
The development of selectable markers for transformation has been a major factor in the successful genetic manipulation of plants. A new selectable marker system has been developed based on bacterial gentamicin-3-N-acetyltransferases [AAC(3)]. These enzymes inactivate aminoglycoside antibiotics by acetylation. Two examples of AAC(3) enzymes have been manipulated to be expressed in plants. Chimeric AAC(3)-III and AAC(3)-IV genes were assembled using the constitutively expressed cauliflower mosaic virus 35S promoter and the nopaline synthase 3′ nontranslated region. These chimeric genes were engineered into vectors for Agrobacterium-mediated plant transformation. Petunia hybrida and Arabidopsis thaliana tissue transformed with these vectors grew in the presence of normally lethal levels of gentamicin. The transformed nature of regenerated Arabidopsis plants was confirmed by DNA hybridization analysis and inheritance of the selectable phenotype in progeny. The chimeric AAC(3)-IV gene has also been used to select transformants in several additional plant species. These results show that the bacterial AAC(3) genes will serve as useful selectable markers in plant tissue culture. Images Fig. 3 Fig. 4 Fig. 5 PMID:16666057
NASA Astrophysics Data System (ADS)
Li, Yane; Fan, Ming; Cheng, Hu; Zhang, Peng; Zheng, Bin; Li, Lihua
2018-01-01
This study aims to develop and test a new imaging marker-based short-term breast cancer risk prediction model. An age-matched dataset of 566 screening mammography cases was used. All ‘prior’ images acquired in the two screening series were negative, while in the ‘current’ screening images, 283 cases were positive for cancer and 283 cases remained negative. For each case, two bilateral cranio-caudal view mammograms acquired from the ‘prior’ negative screenings were selected and processed by a computer-aided image processing scheme, which segmented the entire breast area into nine strip-based local regions, extracted the element regions using difference of Gaussian filters, and computed both global- and local-based bilateral asymmetrical image features. An initial feature pool included 190 features related to the spatial distribution and structural similarity of grayscale values, as well as of the magnitude and phase responses of multidirectional Gabor filters. Next, a short-term breast cancer risk prediction model based on a generalized linear model was built using an embedded stepwise regression analysis method to select features and a leave-one-case-out cross-validation method to predict the likelihood of each woman having image-detectable cancer in the next sequential mammography screening. The area under the receiver operating characteristic curve (AUC) values significantly increased from 0.5863 ± 0.0237 to 0.6870 ± 0.0220 when the model trained by the image features extracted from the global regions and by the features extracted from both the global and the matched local regions (p = 0.0001). The odds ratio values monotonically increased from 1.00-8.11 with a significantly increasing trend in slope (p = 0.0028) as the model-generated risk score increased. In addition, the AUC values were 0.6555 ± 0.0437, 0.6958 ± 0.0290, and 0.7054 ± 0.0529 for the three age groups of 37-49, 50-65, and 66-87 years old, respectively. AUC values of 0.6529 ± 0.1100, 0.6820 ± 0.0353, 0.6836 ± 0.0302 and 0.8043 ± 0.1067 were yielded for the four mammography density sub-groups (BIRADS from 1-4), respectively. This study demonstrated that bilateral asymmetry features extracted from local regions combined with the global region in bilateral negative mammograms could be used as a new imaging marker to assist in the prediction of short-term breast cancer risk.
Introduction of new genetic markers on human chromosomes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Satoh, Hitoshi; Barrett, J.C.; Oshimura, Mitsuo
1991-03-01
The purpose of this study was to use DNA transfection and microcell chromosome transfer techniques to engineer a human chromosome containing multiple biochemical markers for which selectable growth conditions exist. The starting chromosome was a t(X;3)(3pter{yields}3p12::Xq26{yields}Xpter) chromosome from a reciprocal translocation in the normal human fibroblast cell line GM0439. This chromosome was transferred to a HPRT (hypoxanthine phosphoribosyltransferase)-deficient mouse A9 cell line by microcell fusion and selected under growth conditions for the HPRT gene on the human t(X;3) chromosome. A resultant HAT-resistant cell line (A9(GM0439)-1) contained a single human t(X;3) chromosome. These results demonstrate that microcell chromosome transfer can bemore » used to select chromosomes containing multiple markers.« less
Du, Juan; Zhou, Nannan; Liu, Hongxia; Jiang, Fei; Wang, Yubang; Hu, Chunyan; Qi, Hong; Zhong, Caiyun; Wang, Xinru; Li, Zhong
2012-01-01
Estrogen receptor α (ERα) is a marker predictive for response of breast cancers to endocrine therapy. About 30% of breast cancers, however, are hormone- independent because of lack of ERα expression. New strategies are needed for re-expression of ERα and sensitization of ER-negative breast cancer cells to selective ER modulators. The present report shows that arsenic trioxide induces reactivated ERα, providing a target for therapy with ER antagonists. Exposure of ER-negative breast cancer cells to arsenic trioxide leads to re-expression of ERα mRNA and functional ERα protein in in vitro and in vivo. Luciferase reporter gene assays and 3-(4,5-dimethylthiazol-2-yl)- 5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assays show that, upon exposure to arsenic trioxide, formerly unresponsive, ER-negative MDA-MB-231 breast cancer cells become responsive to ER antagonists, 4-hydroxytamoxifen and ICI 182,780. Furthermore, methylation- specific PCR and bisulfite-sequencing PCR assays show that arsenic trioxide induces partial demethylation of the ERα promoter. A methyl donor, S-adenosylmethionine (SAM), reduces the degree of arsenic trioxide-induced re-expression of ERα and demethylation. Moreover, Western blot and ChIP assays show that arsenic trioxide represses expression of DNMT1 and DNMT3a along with partial dissociation of DNMT1 from the ERα promoter. Thus, arsenic trioxide exhibits a previously undefined function which induces re-expression ERα in ER-negative breast cancer cells through demethylation of the ERα promoter. These findings could provide important information regarding the application of therapeutic agents targeting epigenetic changes in breast cancers and potential implication of arsenic trioxide as a new drug for the treatment of ER-negative human breast cancer.
Sørensen, M S; Duch, M; Paludan, K; Jørgensen, P; Pedersen, F S
1992-03-15
Hygromycin B (Hy) resistance, encoded by the prokaryotic gene hph, is commonly used as a dominant selectable marker for gene transfer experiments in mammalian cells. We describe a simple, quantitative dot-blot assay for measuring the activity in crude mammalian cell extracts of Hy phosphotransferase, the product of the hph gene. The assay shows no cross interference with substrates for neomycin phosphotransferase II, the product of the commonly used marker gene neo; hph and neo may thus be useful as a set of two non-interfering selectable marker and reporter genes for gene transfer experiments in mammalian cells.
Marking Embryonic Stem Cells with a 2A Self-Cleaving Peptide: A NKX2-5 Emerald GFP BAC Reporter
Hsiao, Edward C.; Yoshinaga, Yuko; Nguyen, Trieu D.; Musone, Stacy L.; Kim, Judy E.; Swinton, Paul; Espineda, Isidro; Manalac, Carlota; deJong, Pieter J.; Conklin, Bruce R.
2008-01-01
Background Fluorescent reporters are useful for assaying gene expression in living cells and for identifying and isolating pure cell populations from heterogeneous cultures, including embryonic stem (ES) cells. Multiple fluorophores and genetic selection markers exist; however, a system for creating reporter constructs that preserve the regulatory sequences near a gene's native ATG start site has not been widely available. Methodology Here, we describe a series of modular marker plasmids containing independent reporter, bacterial selection, and eukaryotic selection components, compatible with both Gateway recombination and lambda prophage bacterial artificial chromosome (BAC) recombineering techniques. A 2A self-cleaving peptide links the reporter to the native open reading frame. We use an emerald GFP marker cassette to create a human BAC reporter and ES cell reporter line for the early cardiac marker NKX2-5. NKX2-5 expression was detected in differentiating mouse ES cells and ES cell-derived mice. Conclusions Our results describe a NKX2-5 ES cell reporter line for studying early events in cardiomyocyte formation. The results also demonstrate that our modular marker plasmids could be used for generating reporters from unmodified BACs, potentially as part of an ES cell reporter library. PMID:18596956
Power analysis of QTL detection in half-sib families using selective DNA pooling
Baro, Jesús Á; Carleos, Carlos; Corral, Norberto; López, Teresa; Cañón, Javier
2001-01-01
Individual loci of economic importance (QTL) can be detected by comparing the inheritance of a trait and the inheritance of loci with alleles readily identifiable by laboratory methods (genetic markers). Data on allele segregation at the individual level are costly and alternatives have been proposed that make use of allele frequencies among progeny, rather than individual genotypes. Among the factors that may affect the power of the set up, the most important are those intrinsic to the QTL: the additive effect of the QTL, and its dominance, and distance between markers and QTL. Other factors are relative to the choice of animals and markers, such as the frequency of the QTL and marker alleles among dams and sires. Data collection may affect the detection power through the size of half-sib families, selection rate within families, and the technical error incurred when estimating genetic frequencies. We present results for a sensitivity analysis for QTL detection using pools of DNA from selected half-sibs. Simulations showed that conclusive detection may be achieved with families of at least 500 half-sibs if sires are chosen on the criteria that most of their marker alleles are either both missing, or one is fixed, among dams. PMID:11403746
Association Between Molecular Subtypes of Colorectal Cancer and Patient Survival
Phipps, Amanda I.; Limburg, Paul J.; Baron, John A.; Burnett-Hartman, Andrea N.; Weisenberger, Daniel J.; Laird, Peter W.; Sinicrope, Frank A.; Rosty, Christophe; Buchanan, Daniel D.; Potter, John D.; Newcomb, Polly A.
2014-01-01
Background and Aims. Colorectal cancer (CRC) is a heterogeneous disease that can develop via several pathways. Different CRC subtypes, identified based on tumor markers, have been proposed to reflect these pathways. We evaluated the significance of these previously proposed classifications to survival. Methods. Participants in the population-based Seattle Colon Cancer Family Registry were diagnosed with invasive CRC from 1998 through 2007 in western Washington State (n=2706), and followed for survival through 2012. Tumor samples were collected from 2050 participants and classified into 5 subtypes based on combinations of tumor markers: type 1 (microsatellite instability [MSI] high, CpG island methylator phenotype [CIMP] positive, positive for BRAF mutation, negative for KRAS mutation); type 2 (microsatellite stable [MSS] or MSI-low, CIMP-positive, positive for BRAF mutation, negative for KRAS mutation); type 3 (MSS or MSI-low, non-CIMP, negative for BRAF mutation, positive for KRAS mutation); type 4 (MSS or MSI-low, non-CIMP, negative for mutations in BRAF and KRAS); and type 5 (MSI-high, non-CIMP, negative for mutations in BRAF and KRAS). Multiple imputation was used to impute tumor markers for those missing data on 1-3 markers. We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for associations of subtypes with disease-specific and overall mortality, adjusting for age, sex, body mass, diagnosis year, and smoking history. Results. Compared to participants with type 4 tumors (the most predominant), participants with type 2 tumors had the highest disease-specific mortality (HR=2.20, 95% CI: 1.47-3.31); subjects with type 3 tumors also had higher disease-specific mortality (HR=1.32, 95% CI: 1.07-1.63). Subjects with type 5 tumors had the lowest disease-specific mortality (HR=0.30, 95% CI: 0.14-0.66). Associations with overall mortality were similar to those with disease-specific mortality. Conclusions. Based on a large, population-based study, CRC subtypes, defined by proposed etiologic pathways, are associated with marked differences in survival. These findings indicate the clinical importance of studies into the molecular heterogeneity of CRC. PMID:25280443
Association between molecular subtypes of colorectal cancer and patient survival.
Phipps, Amanda I; Limburg, Paul J; Baron, John A; Burnett-Hartman, Andrea N; Weisenberger, Daniel J; Laird, Peter W; Sinicrope, Frank A; Rosty, Christophe; Buchanan, Daniel D; Potter, John D; Newcomb, Polly A
2015-01-01
Colorectal cancer (CRC) is a heterogeneous disease that can develop via several pathways. Different CRC subtypes, identified based on tumor markers, have been proposed to reflect these pathways. We evaluated the significance of these previously proposed classifications to survival. Participants in the population-based Seattle Colon Cancer Family Registry were diagnosed with invasive CRC from 1998 through 2007 in western Washington State (N = 2706), and followed for survival through 2012. Tumor samples were collected from 2050 participants and classified into 5 subtypes based on combinations of tumor markers: type 1 (microsatellite instability [MSI]-high, CpG island methylator phenotype [CIMP] -positive, positive for BRAF mutation, negative for KRAS mutation); type 2 (microsatellite stable [MSS] or MSI-low, CIMP-positive, positive for BRAF mutation, negative for KRAS mutation); type 3 (MSS or MSI low, non-CIMP, negative for BRAF mutation, positive for KRAS mutation); type 4 (MSS or MSI-low, non-CIMP, negative for mutations in BRAF and KRAS); and type 5 (MSI-high, non-CIMP, negative for mutations in BRAF and KRAS). Multiple imputation was used to impute tumor markers for those missing data on 1-3 markers. We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for associations of subtypes with disease-specific and overall mortality, adjusting for age, sex, body mass, diagnosis year, and smoking history. Compared with participants with type 4 tumors (the most predominant), participants with type 2 tumors had the highest disease-specific mortality (HR = 2.20, 95% CI: 1.47-3.31); subjects with type 3 tumors also had higher disease-specific mortality (HR = 1.32, 95% CI: 1.07-1.63). Subjects with type 5 tumors had the lowest disease-specific mortality (HR = 0.30, 95% CI: 0.14-0.66). Associations with overall mortality were similar to those with disease-specific mortality. Based on a large, population-based study, CRC subtypes, defined by proposed etiologic pathways, are associated with marked differences in survival. These findings indicate the clinical importance of studies into the molecular heterogeneity of CRC. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
Marker-assisted combination of major genes for pathogen resistance in potato.
Gebhardt, C; Bellin, D; Henselewski, H; Lehmann, W; Schwarzfischer, J; Valkonen, J P T
2006-05-01
Closely linked PCR-based markers facilitate the tracing and combining of resistance factors that have been introgressed previously into cultivated potato from different sources. Crosses were performed to combine the Ry ( adg ) gene for extreme resistance to Potato virus Y (PVY) with the Gro1 gene for resistance to the root cyst nematode Globodera rostochiensis and the Rx1 gene for extreme resistance to Potato virus X (PVX), or with resistance to potato wart (Synchytrium endobioticum). Marker-assisted selection (MAS) using four PCR-based diagnostic assays was applied to 110 F1 hybrids resulting from four 2x by 4x cross-combinations. Thirty tetraploid plants having the appropriate marker combinations were selected and tested for presence of the corresponding resistance traits. All plants tested showed the expected resistant phenotype. Unexpectedly, the plants segregated for additional resistance to pathotypes 1, 2 and 6 of S. endobioticum, which was subsequently shown to be inherited from the PVY resistant parents of the crosses. The selected plants can be used as sources of multiple resistance traits in pedigree breeding and are available from a potato germplasm bank.
Additive Genetic Variability and the Bayesian Alphabet
Gianola, Daniel; de los Campos, Gustavo; Hill, William G.; Manfredi, Eduardo; Fernando, Rohan
2009-01-01
The use of all available molecular markers in statistical models for prediction of quantitative traits has led to what could be termed a genomic-assisted selection paradigm in animal and plant breeding. This article provides a critical review of some theoretical and statistical concepts in the context of genomic-assisted genetic evaluation of animals and crops. First, relationships between the (Bayesian) variance of marker effects in some regression models and additive genetic variance are examined under standard assumptions. Second, the connection between marker genotypes and resemblance between relatives is explored, and linkages between a marker-based model and the infinitesimal model are reviewed. Third, issues associated with the use of Bayesian models for marker-assisted selection, with a focus on the role of the priors, are examined from a theoretical angle. The sensitivity of a Bayesian specification that has been proposed (called “Bayes A”) with respect to priors is illustrated with a simulation. Methods that can solve potential shortcomings of some of these Bayesian regression procedures are discussed briefly. PMID:19620397
Rouam, Sigrid; Broët, Philippe
2013-08-01
To identify genomic markers with consistent effect on tumor dynamics across multiple cancer series, discrimination indices based on proportional hazards models can be used since they do not depend heavily on the sample size. However, the underlying assumption of proportionality of the hazards does not always hold, especially when the studied population is a mixture of cured and uncured patients, like in early-stage cancers. We propose a novel index that quantifies the capability of a genomic marker to separate uncured patients, according to their time-to-event outcomes. It allows to identify genomic markers characterizing tumor growth dynamic across multiple studies. Simulation results show that our index performs better than classical indices based on the Cox model. It is neither affected by the sample size nor the cure rate fraction. In a cross-study of early-stage breast cancers, the index allows to select genomic markers with a potential consistent effect on tumor growth dynamics. Copyright © 2013 Elsevier Inc. All rights reserved.
Hu, Zhan; Ding, Xuezhi; Hu, Shengbiao; Sun, Yunjun; Xia, Liqiu
2013-12-01
Marker-free, genetically-modified rice was created by the tissue-specifically regulated Cre/loxP system, in which the Cre recombinase gene and hygromycin phosphotransferase gene (hpt) were flanked by two directly oriented loxP sites. Cre expression was activated by the tissue-specific promoter OsMADS45 in flower or napin in seed, resulting in simultaneous excision of the recombinase and marker genes. Segregation of T1 progeny was performed to select recombined plants. The excision was confirmed by PCR, Southern blot and sequence analyses indicating that efficiency varied from 10 to 53 % for OsMADS45 and from 12 to 36 % for napin. The expression of cry1Ac and vip3A was detected by RT-PCR analysis in marker-free transgenic rice. These results suggested that our tissue-specifically regulated Cre/loxP system could auto-excise marker genes from transgenic rice and alleviate public concerns about the security of GM crops.
Markers of the denormalisation of smoking and the tobacco industry.
Chapman, S; Freeman, B
2008-02-01
In nations with histories of declining smoking prevalence and comprehensive tobacco control policies, smoking-positive cultures have been severely eroded. Smoking, smokers and the tobacco industry are today routinely depicted in everyday discourse and media representations in a variety of overwhelmingly negative ways. Several authors have invoked Erving Goffman's notions of stigmatization to describe the process and impact of this radical transformation, which importantly includes motivating smoking cessation. Efforts to describe nations' progress toward comprehensive tobacco control have hitherto taken little account of the role of cultural change to the meaning of smoking and the many ways in which it has become denormalised. This paper identifies a diversity of generally undocumented yet pervasive markers of the "spoiled identity" of smoking, smokers and the tobacco industry, illustrated with examples from Australia, a nation with advanced tobacco control. We caution about some important negative consequences arising from the stigmatization of smokers. We recommend that schemes rating the comprehensiveness of national tobacco control should be supplemented by documentation of markers of this denormalisation.
Diagnostic/prognostic molecular cytogenetic follow-up applied in satellited marker cases
DOE Office of Scientific and Technical Information (OSTI.GOV)
Papenhausen, P.R.; Anderson, S.
1994-09-01
Special caution needs to be exercised in offering a good prognosis in Prader-Willi probe negative 15-derived marker cases, since it is clear that phenotypic effects can still be associated with the apparent presence of proximal sequences. We have had two postnatal cases in this category, one which was inherited from an unaffected paternal (non-mosaic) carrier, possibly demonstrating imprinting effects. Familial studies are continuing in this case. Although the D22/S9 locus appears diagnostic of cateye syndrome (CES), the dual specificity of the 14/22 centromeric probe leaves the possibility of a poor prognosis 14 derivation when the CES probe is negative. Therefore,more » it is imperative that proximal long arm 13, 14, 21 and more proximal 15 FISH probes be implemented so that a phenotypically correlated database may indicate the proper FISH probes necessary for accurate prognosis. Bisatellited markers is which a bipartite centromeric probe signal was found were considered to be higher risk than those with the single signal in counseling.« less
Role of immune activation in CD4+ T-cell depletion in HIV-1 infected Indian patients.
Vajpayee, M; Kaushik, S; Sreenivas, V; Mojumdar, K; Mendiratta, S; Chauhan, N K
2009-01-01
The correlation of immune activation with CD4(+) depletion and HIV-1 disease progression has been evidenced by several studies involving mainly clade B virus. However, this needs to be investigated in developing countries such as India predominately infected with clade C virus. In a cross-sectional study of 68 antiretroviral treatment naïve, HIV-1 infected Indian patients, we studied the association between CD4(+) T cells, plasma HIV-1 RNA levels, and immune activation markers using unadjusted and adjusted correlative analyses. Significant negative correlations of higher magnitude were observed between the CD4(+) T cell percentages and plasma HIV-1 RNA levels in the study population when adjusted for the effects of immune activation markers. However, the negative association of CD4(+) T cells with immune activation markers remained unaffected when controlled for the effects of plasma HIV-1 RNA levels. Our results support the important role of immune activation in CD4(+) T cell depletion and disease progression during untreated HIV-1 infection.
Sudheer Pamidimarri, D V N; Singh, Sweta; Mastan, Shaik G; Patel, Jalpa; Reddy, Muppala P
2009-07-01
Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD, 238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed, seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS).
Blochlinger, K; Diggelmann, H
1984-12-01
The DNA coding sequence for the hygromycin B phosphotransferase gene was placed under the control of the regulatory sequences of a cloned long terminal repeat of Moloney sarcoma virus. This construction allowed direct selection for hygromycin B resistance after transfection of eucaryotic cell lines not naturally resistant to this antibiotic, thus providing another dominant marker for DNA transfer in eucaryotic cells.
Blochlinger, K; Diggelmann, H
1984-01-01
The DNA coding sequence for the hygromycin B phosphotransferase gene was placed under the control of the regulatory sequences of a cloned long terminal repeat of Moloney sarcoma virus. This construction allowed direct selection for hygromycin B resistance after transfection of eucaryotic cell lines not naturally resistant to this antibiotic, thus providing another dominant marker for DNA transfer in eucaryotic cells. Images PMID:6098829
Elliot, Ari J.; Chapman, Benjamin P.
2016-01-01
Objective To investigate interactions of psychological resources and socioeconomic status in predicting markers of systemic inflammation, as well as potential gender differences and the explanatory role of childhood and adult stress exposures, health behaviors, and negative and positive affect. Method We utilized a sample of adults from the Midlife in the United States Survey (MIDUS) who provided biomarker data (N=1,152). SES was operationalized as a composite of education, income, and occupational prestige, and psychological resources as a latent factor measured with optimism, perceived control, and self-esteem. Linear regression models examined these two factors and their interaction in predicting interleukin-6 (IL-6) and C-reactive protein (CRP) measured on average 2 years later, as well as three-way interactions involving gender and the impact of covariate adjustment. Results Psychological resources interacted with SES in men (for IL-6: p<.001; for CRP: p=.04) but not in women. In men, greater psychological resources were associated with lower concentrations of IL-6 at lower levels of SES, but higher concentrations of both markers at higher levels of SES. The inverse association between resources and IL-6 at low SES was moderately attenuated upon adjustment for negative affect. Conclusion Socioeconomic status might modulate the linkage between psychological resources and systemic inflammation in men. At lower levels of SES, resources may be related to lower inflammation in part through lower negative affect. Associations with higher inflammation at higher SES add to growing evidence suggesting that adaptive psychological characteristics may be associated with markers of poorer physiological function under certain conditions. PMID:27280368
mazF, a novel counter-selectable marker for unmarked chromosomal manipulation in Bacillus subtilis.
Zhang, Xiao-Zhou; Yan, Xin; Cui, Zhong-Li; Hong, Qing; Li, Shun-Peng
2006-05-19
Here, we present a novel method for the directed genetic manipulation of the Bacillus subtilis chromosome free of any selection marker. Our new approach employed the Escherichia coli toxin gene mazF as a counter-selectable marker. The mazF gene was placed under the control of an isopropyl-beta-D-thiogalactopyranoside (IPTG)-inducible expression system and associated with a spectomycin-resistance gene to form the MazF cassette, which was flanked by two directly-repeated (DR) sequences. A double-crossover event between the linearized delivery vector and the chromosome integrated the MazF cassette into a target locus and yielded an IPTG-sensitive strain with spectomycin-resistance, in which the wild-type chromosome copy had been replaced by the modified copy at the targeted locus. Another single-crossover event between the two DR sequences led to the excision of the MazF cassette and generated a strain with IPTG resistance, thereby realizing the desired alteration to the chromosome without introducing any unwanted selection markers. We used this method repeatedly and successfully to inactivate a specific gene, to introduce a gene of interest and to realize the in-frame deletion of a target gene in the same strain. As there is no prerequisite strain for this method, it will be a powerful and universal tool.
Vidal, Newton Medeiros; Grazziotin, Ana Laura; Ramos, Helaine Christine Cancela; Pereira, Messias Gonzaga; Venancio, Thiago Motta
2014-01-01
Carica papaya (papaya) is an economically important tropical fruit. Molecular marker-assisted selection is an inexpensive and reliable tool that has been widely used to improve fruit quality traits and resistance against diseases. In the present study we report the development and validation of an atlas of papaya simple sequence repeat (SSR) markers. We integrated gene predictions and functional annotations to provide a gene-centered perspective for marker-assisted selection studies. Our atlas comprises 160,318 SSRs, from which 21,231 were located in genic regions (i.e. inside exons, exon-intron junctions or introns). A total of 116,453 (72.6%) of all identified repeats were successfully mapped to one of the nine papaya linkage groups. Primer pairs were designed for markers from 9,594 genes (34.5% of the papaya gene complement). Using papaya-tomato orthology assessments, we assembled a list of 300 genes (comprising 785 SSRs) potentially involved in fruit ripening. We validated our atlas by screening 73 SSR markers (including 25 fruit ripening genes), achieving 100% amplification rate and uncovering 26% polymorphism rate between the parental genotypes (Sekati and JS12). The SSR atlas presented here is the first comprehensive gene-centered collection of annotated and genome positioned papaya SSRs. These features combined with thousands of high-quality primer pairs make the atlas an important resource for the papaya research community. PMID:25393538
Genomic selection for slaughter age in pigs using the Cox frailty model.
Santos, V S; Martins Filho, S; Resende, M D V; Azevedo, C F; Lopes, P S; Guimarães, S E F; Glória, L S; Silva, F F
2015-10-19
The aim of this study was to compare genomic selection methodologies using a linear mixed model and the Cox survival model. We used data from an F2 population of pigs, in which the response variable was the time in days from birth to the culling of the animal and the covariates were 238 markers [237 single nucleotide polymorphism (SNP) plus the halothane gene]. The data were corrected for fixed effects, and the accuracy of the method was determined based on the correlation of the ranks of predicted genomic breeding values (GBVs) in both models with the corrected phenotypic values. The analysis was repeated with a subset of SNP markers with largest absolute effects. The results were in agreement with the GBV prediction and the estimation of marker effects for both models for uncensored data and for normality. However, when considering censored data, the Cox model with a normal random effect (S1) was more appropriate. Since there was no agreement between the linear mixed model and the imputed data (L2) for the prediction of genomic values and the estimation of marker effects, the model S1 was considered superior as it took into account the latent variable and the censored data. Marker selection increased correlations between the ranks of predicted GBVs by the linear and Cox frailty models and the corrected phenotypic values, and 120 markers were required to increase the predictive ability for the characteristic analyzed.
Li, Zhucui; Lu, Yan; Guo, Yufeng; Cao, Haijie; Wang, Qinhong; Shui, Wenqing
2018-10-31
Data analysis represents a key challenge for untargeted metabolomics studies and it commonly requires extensive processing of more than thousands of metabolite peaks included in raw high-resolution MS data. Although a number of software packages have been developed to facilitate untargeted data processing, they have not been comprehensively scrutinized in the capability of feature detection, quantification and marker selection using a well-defined benchmark sample set. In this study, we acquired a benchmark dataset from standard mixtures consisting of 1100 compounds with specified concentration ratios including 130 compounds with significant variation of concentrations. Five software evaluated here (MS-Dial, MZmine 2, XCMS, MarkerView, and Compound Discoverer) showed similar performance in detection of true features derived from compounds in the mixtures. However, significant differences between untargeted metabolomics software were observed in relative quantification of true features in the benchmark dataset. MZmine 2 outperformed the other software in terms of quantification accuracy and it reported the most true discriminating markers together with the fewest false markers. Furthermore, we assessed selection of discriminating markers by different software using both the benchmark dataset and a real-case metabolomics dataset to propose combined usage of two software for increasing confidence of biomarker identification. Our findings from comprehensive evaluation of untargeted metabolomics software would help guide future improvements of these widely used bioinformatics tools and enable users to properly interpret their metabolomics results. Copyright © 2018 Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
To date, nearly 10,000 SSR-based markers have been identified by various research groups around the world, but less than 14.5% showed polymorphism in peanut and only 6.4% were mapped. Low levels of polymorphism limit the application of marker assisted selection (MAS) in peanut breeding programs. I...
USDA-ARS?s Scientific Manuscript database
Genetic markers in casein (CSN1S1) and thyroglobulin (TG) genes have previously been associated with fat distribution in cattle. Determining the nature of these genetic associations (additive, recessive, or dominant) has been difficult because both markers have small minor allele frequencies in mos...
Wada, Yoshihiro; Maeda, Yoshihiro; Kubo, Tatsuko; Kikuchi, Ken; Eto, Masatoshi; Imamura, Takahisa
2016-11-01
Patients with aggressive urothelial cell carcinoma (UCC) that undergo radical cystectomy or nephroureterectomy exhibit markedly high rates of disease recurrence and mortality. To select appropriate adjuvant thxerapies in addition to radical surgery, the identification of predictive prognostic markers for UCC patients is required. The aim of the present study was to identify such markers, by evaluating the association of UCC complement component 5 (C5) fragment a (C5a)receptor (C5aR) expression, detected using immunohistochemistry, with clinicopathological parameters and survival outcomes of UCC patients. The results revealed that C5aR was expressed in cancer cells, particularly at the invasive front, but not in noncancerous urothelial cells or adjacent cells. The UCC C5aR-positive rate of patients treated with radical surgeries was 73% (38/52) and the rate was 83% (20/24) at stages I-II of disease. No correlation between C5aR expression and any of clinicopathological parameters, which included gender, tumor location, World Health Organization grade, T stage, vessel invasion and stage of disease, was identified. However, univariate and multivariate analyses revealed that C5aR-positive UCC patients exhibited significantly lower overall survival rates [hazard ratio (HR), 3.14; 95% confidence interval (CI), 1.03-9.60; P=0.035 and HR, 3.92; 95% CI, 1.15-13.4; P=0.029, respectively] and 5-year survival rates (0.42 vs. 0.83) compared with C5aR-negative UCC patients. Furthermore, 5-year survival and disease-specific survival rates were lower in patients with C5aR-positive UCC (0.51; 95% CI, 0.30-0.71) than patients with C5aR-negative UCC (0.83; 95% CI, 0.62-1.00). These results indicate that UCC C5aR expression is predictive of poor patient outcomes and thus may lead to the appropriate selection of adjuvant therapies at earlier UCC stages, which could improve patient prognosis.
Wada, Yoshihiro; Maeda, Yoshihiro; Kubo, Tatsuko; Kikuchi, Ken; Eto, Masatoshi; Imamura, Takahisa
2016-01-01
Patients with aggressive urothelial cell carcinoma (UCC) that undergo radical cystectomy or nephroureterectomy exhibit markedly high rates of disease recurrence and mortality. To select appropriate adjuvant thxerapies in addition to radical surgery, the identification of predictive prognostic markers for UCC patients is required. The aim of the present study was to identify such markers, by evaluating the association of UCC complement component 5 (C5) fragment a (C5a)receptor (C5aR) expression, detected using immunohistochemistry, with clinicopathological parameters and survival outcomes of UCC patients. The results revealed that C5aR was expressed in cancer cells, particularly at the invasive front, but not in noncancerous urothelial cells or adjacent cells. The UCC C5aR-positive rate of patients treated with radical surgeries was 73% (38/52) and the rate was 83% (20/24) at stages I–II of disease. No correlation between C5aR expression and any of clinicopathological parameters, which included gender, tumor location, World Health Organization grade, T stage, vessel invasion and stage of disease, was identified. However, univariate and multivariate analyses revealed that C5aR-positive UCC patients exhibited significantly lower overall survival rates [hazard ratio (HR), 3.14; 95% confidence interval (CI), 1.03–9.60; P=0.035 and HR, 3.92; 95% CI, 1.15–13.4; P=0.029, respectively] and 5-year survival rates (0.42 vs. 0.83) compared with C5aR-negative UCC patients. Furthermore, 5-year survival and disease-specific survival rates were lower in patients with C5aR-positive UCC (0.51; 95% CI, 0.30–0.71) than patients with C5aR-negative UCC (0.83; 95% CI, 0.62–1.00). These results indicate that UCC C5aR expression is predictive of poor patient outcomes and thus may lead to the appropriate selection of adjuvant therapies at earlier UCC stages, which could improve patient prognosis. PMID:27895761
On the Early Left-Anterior Negativity (ELAN) in Syntax Studies
ERIC Educational Resources Information Center
Steinhauer, Karsten; Drury, John E.
2012-01-01
Within the framework of Friederici's (2002) neurocognitive model of sentence processing, the early left anterior negativity (ELAN) in event-related potentials (ERPs) has been claimed to be a brain marker of syntactic first-pass parsing. As ELAN components seem to be exclusively elicited by word category violations (phrase structure violations),…
Does genomic selection have a future in plant breeding?
Jonas, Elisabeth; de Koning, Dirk-Jan
2013-09-01
Plant breeding largely depends on phenotypic selection in plots and only for some, often disease-resistance-related traits, uses genetic markers. The more recently developed concept of genomic selection, using a black box approach with no need of prior knowledge about the effect or function of individual markers, has also been proposed as a great opportunity for plant breeding. Several empirical and theoretical studies have focused on the possibility to implement this as a novel molecular method across various species. Although we do not question the potential of genomic selection in general, in this Opinion, we emphasize that genomic selection approaches from dairy cattle breeding cannot be easily applied to complex plant breeding. Copyright © 2013 Elsevier Ltd. All rights reserved.
Genetic Markers of Human Evolution Are Enriched in Schizophrenia.
Srinivasan, Saurabh; Bettella, Francesco; Mattingsdal, Morten; Wang, Yunpeng; Witoelar, Aree; Schork, Andrew J; Thompson, Wesley K; Zuber, Verena; Winsvold, Bendik S; Zwart, John-Anker; Collier, David A; Desikan, Rahul S; Melle, Ingrid; Werge, Thomas; Dale, Anders M; Djurovic, Srdjan; Andreassen, Ole A
2016-08-15
Why schizophrenia has accompanied humans throughout our history despite its negative effect on fitness remains an evolutionary enigma. It is proposed that schizophrenia is a by-product of the complex evolution of the human brain and a compromise for humans' language, creative thinking, and cognitive abilities. We analyzed recent large genome-wide association studies of schizophrenia and a range of other human phenotypes (anthropometric measures, cardiovascular disease risk factors, immune-mediated diseases) using a statistical framework that draws on polygenic architecture and ancillary information on genetic variants. We used information from the evolutionary proxy measure called the Neanderthal selective sweep (NSS) score. Gene loci associated with schizophrenia are significantly (p = 7.30 × 10(-9)) more prevalent in genomic regions that are likely to have undergone recent positive selection in humans (i.e., with a low NSS score). Variants in brain-related genes with a low NSS score confer significantly higher susceptibility than variants in other brain-related genes. The enrichment is strongest for schizophrenia, but we cannot rule out enrichment for other phenotypes. The false discovery rate conditional on the evolutionary proxy points to 27 candidate schizophrenia susceptibility loci, 12 of which are associated with schizophrenia and other psychiatric disorders or linked to brain development. Our results suggest that there is a polygenic overlap between schizophrenia and NSS score, a marker of human evolution, which is in line with the hypothesis that the persistence of schizophrenia is related to the evolutionary process of becoming human. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
DDX4 (DEAD box polypeptide 4) colocalizes with cancer stem cell marker CD133 in ovarian cancers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Ki Hyung; Biomedical Research Institute and Pusan Cancer Center, Pusan National University Hospital, Busan; Kang, Yun-Jeong
Highlights: • Germ cell marker DDX4 was significantly increased in ovarian cancer. • Ovarian cancer stem cell marker CD133 was significantly increased in ovarian cancer. • DDX4 and CD133 were mostly colocalized in various types of ovarian cancer tissues. • CD133 positive ovarian cancer cells also express DDX4 whereas CD133-negative cells did not possess DDX4. • Germ cell marker DDX4 has the potential of ovarian cancer stem cell marker. - Abstract: DDX4 (DEAD box polypeptide 4), characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), is an RNA helicase which is implicated in various cellular processes involving the alteration of RNA secondarymore » structure, such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. DDX4 is known to be a germ cell-specific protein and is used as a sorting marker of germline stem cells for the production of oocytes. A recent report about DDX4 in ovarian cancer showed that DDX4 is overexpressed in epithelial ovarian cancer and disrupts a DNA damage-induced G2 checkpoint. We investigated the relationship between DDX4 and ovarian cancer stem cells by analyzing the expression patterns of DDX4 and the cancer stem cell marker CD133 in ovarian cancers via tissue microarray. Both DDX4 and CD133 were significantly increased in ovarian cancer compared to benign tumors, and showed similar patterns of expression. In addition, DDX4 and CD133 were mostly colocalized in various types of ovarian cancer tissues. Furthermore, almost all CD133 positive ovarian cancer cells also express DDX4 whereas CD133-negative cells did not possess DDX4, suggesting a strong possibility that DDX4 plays an important role in cancer stem cells, and/or can be used as an ovarian cancer stem cell marker.« less
Ipek, M; Seker, M; Ipek, A; Gul, M K
2015-03-31
The purpose of this study was to characterize olive core collection with amplified fragment length polymorphism (AFLP) markers and fruit traits and to determine AFLP markers significantly associated with these fruit characters in olive. A total of 168 polymorphic AFLP markers generated by five primer combinations and nine fruit traits were used to characterize relationships between 18 olive cultivars. Although all olive cultivars were discriminated from each other by either AFLP markers (<0.75 similarity level) or fruit traits, clustering based on the AFLP markers and fruit traits was not significantly correlated (r = 0.13). Partial clustering of olive cultivars by AFLP markers according to their geographical origin was observed. Associations of AFLP markers with fruits were determined using a multiple-regression analysis with stepwise addition of AFLP markers. Significant associations between eight AFLP markers and fruit traits were identified. While five AFLP markers demonstrated significant negative correlation with fruit and stone weight, width and length and total polyphenols (P < 0.05), three AFLP markers displayed significant positive correlation with α-tocopherol and γ-tocopherol (P < 0.01). This is the first report on the association of molecular markers with fruit traits in olive. Molecular markers associated with morphological and agronomic traits could be utilized for the breeding of olive cultivars. However, the association power of these markers needs to be confirmed in larger populations, and highly correlated markers should then be converted to PCR-based DNA markers such as sequence-characterized amplified region markers for better utilization.
1990-09-01
expanded in a specific direction if movement is indicated. Controlled dumping at precise coordinates or at marker buoys may reduce the required survey area...of the meters or theft of the marker buoys. Subsurface markers using acoustic releases prevent vandalism and loss of marker buoys, but they...data from field studies such as impact investigations ’Underwood 1981; Heck and Horowitz 1984; Hurlbert 1984; Millard and Lettenmaier 1986; Stewart
Fast internal marker tracking algorithm for onboard MV and kV imaging systems
Mao, W.; Wiersma, R. D.; Xing, L.
2008-01-01
Intrafraction organ motion can limit the advantage of highly conformal dose techniques such as intensity modulated radiation therapy (IMRT) due to target position uncertainty. To ensure high accuracy in beam targeting, real-time knowledge of the target location is highly desired throughout the beam delivery process. This knowledge can be gained through imaging of internally implanted radio-opaque markers with fluoroscopic or electronic portal imaging devices (EPID). In the case of MV based images, marker detection can be problematic due to the significantly lower contrast between different materials in comparison to their kV-based counterparts. This work presents a fully automated algorithm capable of detecting implanted metallic markers in both kV and MV images with high consistency. Using prior CT information, the algorithm predefines the volumetric search space without manual region-of-interest (ROI) selection by the user. Depending on the template selected, both spherical and cylindrical markers can be detected. Multiple markers can be simultaneously tracked without indexing confusion. Phantom studies show detection success rates of 100% for both kV and MV image data. In addition, application of the algorithm to real patient image data results in successful detection of all implanted markers for MV images. Near real-time operational speeds of ∼10 frames∕sec for the detection of five markers in a 1024×768 image are accomplished using an ordinary PC workstation. PMID:18561670
Risk Classification with an Adaptive Naive Bayes Kernel Machine Model.
Minnier, Jessica; Yuan, Ming; Liu, Jun S; Cai, Tianxi
2015-04-22
Genetic studies of complex traits have uncovered only a small number of risk markers explaining a small fraction of heritability and adding little improvement to disease risk prediction. Standard single marker methods may lack power in selecting informative markers or estimating effects. Most existing methods also typically do not account for non-linearity. Identifying markers with weak signals and estimating their joint effects among many non-informative markers remains challenging. One potential approach is to group markers based on biological knowledge such as gene structure. If markers in a group tend to have similar effects, proper usage of the group structure could improve power and efficiency in estimation. We propose a two-stage method relating markers to disease risk by taking advantage of known gene-set structures. Imposing a naive bayes kernel machine (KM) model, we estimate gene-set specific risk models that relate each gene-set to the outcome in stage I. The KM framework efficiently models potentially non-linear effects of predictors without requiring explicit specification of functional forms. In stage II, we aggregate information across gene-sets via a regularization procedure. Estimation and computational efficiency is further improved with kernel principle component analysis. Asymptotic results for model estimation and gene set selection are derived and numerical studies suggest that the proposed procedure could outperform existing procedures for constructing genetic risk models.
Labouesse, Marie A; Gertz, Erik R; Piccolo, Brian D; Souza, Elaine C; Schuster, Gertrud U; Witbracht, Megan G; Woodhouse, Leslie R; Adams, Sean H; Keim, Nancy L; Van Loan, Marta D
2014-07-01
Weight loss reduces co-morbidities of obesity, but decreases bone mass. Our aims were to (1) determine if adequate dairy intake attenuates weight loss-induced bone loss; (2) evaluate the associations of endocrine, inflammatory and bone markers, anthropometric and other parameters to bone mineral density and content (BMD, BMC) pre- and post-weight loss; and (3) model the contribution of these variables to post weight-loss BMD and BMC. Overweight/obese women (BMI: 28-37 kg/m2) were enrolled in an energy reduced (-500 kcal/d; -2092 kJ/d) diet with adequate dairy (AD: 3-4 servings/d; n=25, 32.2±8.8 years) or low dairy (LD: ≤1 serving/d; n=26, 31.7±8.4 years). BMD, BMC and body composition were measured by DXA. Bone markers (CTX, PYD, BAP, OC), endocrine (PTH, vitamin D, leptin, adiponectin, ghrelin, amylin, insulin, GLP-1, PAI-1, HOMA) and inflammatory markers (CRP, IL1-β, IL-6, IL-8, TNF-α, cortisol) were measured in serum or plasma. PA was assessed by accelerometry. Following weight loss, AD intake resulted in significantly greater (p=0.004) lumbar spine BMD and serum osteocalcin (p=0.004) concentration compared to LD. Pre- and post-body fat was negatively associated with hip and lumbar spine BMC (r=-0.28, p=0.04 to -0.45, p=0.001). Of note were the significant negative associations among bone markers and IL-1β, TNFα and CRP ranging from r = -0.29 (p=0.04) to r = -0.34 (p=0.01); magnitude of associations did not change with weight loss. Adiponectin was negatively related to change in osteocalcin. Factor analysis resulted in 8 pre- and post-weight loss factors. Pre-weight loss factors accounted for 13.7% of the total variance in pre-weight loss hip BMD; post-weight loss factors explained 19.6% of the total variance in post-weight loss hip BMD. None of the factors contributed to the variance in lumbar spine BMD. AD during weight loss resulted in higher lumbar spine BMD and osteocalcin compared to LD. Significant negative associations were observed between bone and inflammatory markers suggesting that inflammation suppresses bone metabolism. Using factor analysis, 19.6% of total variance in post-weight loss hip BMD could be explained by endocrine, immune, and anthropometric variables, but not lumbar spine BMD. Published by Elsevier Inc.
Labouesse, Marie A.; Gertz, Erik R.; Piccolo, Brian D.; Souza, Elaine C.; Schuster, Gertrud U.; Witbracht, Megan G.; Woodhouse, Leslie R.; Adams, Sean H.; Keim, Nancy L.; Van Loan, Marta D.
2015-01-01
INTRODUCTION Weight loss reduces co-morbidities of obesity, but decreases bone mass. PURPOSE Our aims were to 1) determine if adequate dairy intake attenuates weight loss-induced bone loss; 2) evaluate the associations of endocrine, inflammatory and bone markers, anthropometric and other parameters to bone mineral density and content (BMD, BMC) pre- and post-weight loss; 3) model the contribution of these variables to post weight-loss BMD and BMC METHODS Overweight/obese women (BMI: 28–37 kg/m2) were enrolled in an energy reduced (−500 kcal/d; −2092 kJ/d) diet with adequate dairy (AD: 3–4 servings/d; n=25, 32.2 ± 8.8y) or low dairy (LD: ≤ 1 serving/d; n=26, 31.7 ± 8.4 y). BMD, BMC and body composition were measured by DXA. Bone markers (CTX, PYD, BAP, OC), endocrine (PTH, vitamin D, leptin, adiponectin, ghrelin, amylin, insulin, GLP-1, PAI-1, HOMA) and inflammatory markers (CRP, IL1-β, IL-6, IL-8, TNF-α, cortisol) were measured in serum or plasma. PA was assessed by accelerometry. RESULTS Following weight loss, AD intake resulted in significantly greater (p= 0.004) lumbar spine BMD and serum osteocalcin (p=0.004) concentration compared to LD. Pre- and post- body fat were negatively associated with hip and lumbar spine BMC (r= −0.28, p=0.04 to −0.45, p=0.001). Of note were the significant negative associations among bone markers and IL-1β, TNFα and CRP ranging from r = −0.29 (p=0.04) to r = −0.34 (p=0.01); magnitude of associations did not change with weight loss. Adiponectin was negatively related to change in osteocalcin. Factor analysis resulted in 8 pre- and post-weight loss Factors. Pre-weight loss Factors accounted for 13.7% of the total variance in pre-weight loss hip BMD; post-weight loss Factors explained 19.6% of the total variance in post-weight loss hip BMD. None of the Factors contributed to the variance in lumbar spine BMD. CONCLUSION AD during weight loss resulted in higher lumbar spine BMD and osteocalcin compared to LD. Significant negative associations were observed between bone and inflammatory markers suggesting inflammation suppresses bone metabolism. Using Factor Analysis, 19.6% of total variance in post-weight loss hip BMD could be explained by endocrine, immune, and anthropometric variables, but not lumbar spine BMD. PMID:24709689
Massa, Alicia N; Manrique-Carpintero, Norma C; Coombs, Joseph J; Zarka, Daniel G; Boone, Anne E; Kirk, William W; Hackett, Christine A; Bryan, Glenn J; Douches, David S
2015-09-14
The objective of this study was to construct a single nucleotide polymorphism (SNP)-based genetic map at the cultivated tetraploid level to locate quantitative trait loci (QTL) contributing to economically important traits in potato (Solanum tuberosum L.). The 156 F1 progeny and parents of a cross (MSL603) between "Jacqueline Lee" and "MSG227-2" were genotyped using the Infinium 8303 Potato Array. Furthermore, the progeny and parents were evaluated for foliar late blight reaction to isolates of the US-8 genotype of Phytophthora infestans (Mont.) de Bary and vine maturity. Linkage analyses and QTL mapping were performed using a novel approach that incorporates allele dosage information. The resulting genetic maps contained 1972 SNP markers with an average density of 1.36 marker per cM. QTL mapping identified the major source of late blight resistance in "Jacqueline Lee." The best SNP marker mapped ~0.54 Mb from a resistance hotspot on the long arm of chromosome 9. For vine maturity, the major-effect QTL was located on chromosome 5 with allelic effects from both parents. A candidate SNP marker for this trait mapped ~0.25 Mb from the StCDF1 gene, which is a candidate gene for the maturity trait. The identification of markers for P. infestans resistance will enable the introgression of multiple sources of resistance through marker-assisted selection. Moreover, the discovery of a QTL for late blight resistance not linked to the QTL for vine maturity provides the opportunity to use marker-assisted selection for resistance independent of the selection for vine maturity classifications. Copyright © 2015 Massa et al.
Massa, Alicia N.; Manrique-Carpintero, Norma C.; Coombs, Joseph J.; Zarka, Daniel G.; Boone, Anne E.; Kirk, William W.; Hackett, Christine A.; Bryan, Glenn J.; Douches, David S.
2015-01-01
The objective of this study was to construct a single nucleotide polymorphism (SNP)-based genetic map at the cultivated tetraploid level to locate quantitative trait loci (QTL) contributing to economically important traits in potato (Solanum tuberosum L.). The 156 F1 progeny and parents of a cross (MSL603) between “Jacqueline Lee” and “MSG227-2” were genotyped using the Infinium 8303 Potato Array. Furthermore, the progeny and parents were evaluated for foliar late blight reaction to isolates of the US-8 genotype of Phytophthora infestans (Mont.) de Bary and vine maturity. Linkage analyses and QTL mapping were performed using a novel approach that incorporates allele dosage information. The resulting genetic maps contained 1972 SNP markers with an average density of 1.36 marker per cM. QTL mapping identified the major source of late blight resistance in “Jacqueline Lee.” The best SNP marker mapped ∼0.54 Mb from a resistance hotspot on the long arm of chromosome 9. For vine maturity, the major-effect QTL was located on chromosome 5 with allelic effects from both parents. A candidate SNP marker for this trait mapped ∼0.25 Mb from the StCDF1 gene, which is a candidate gene for the maturity trait. The identification of markers for P. infestans resistance will enable the introgression of multiple sources of resistance through marker-assisted selection. Moreover, the discovery of a QTL for late blight resistance not linked to the QTL for vine maturity provides the opportunity to use marker-assisted selection for resistance independent of the selection for vine maturity classifications. PMID:26374597
Shimizu, Tokurou; Kitajima, Akira; Nonaka, Keisuke; Yoshioka, Terutaka; Ohta, Satoshi; Goto, Shingo; Toyoda, Atsushi; Fujiyama, Asao; Mochizuki, Takako; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu
2016-01-01
Most indigenous citrus varieties are assumed to be natural hybrids, but their parentage has so far been determined in only a few cases because of their wide genetic diversity and the low transferability of DNA markers. Here we infer the parentage of indigenous citrus varieties using simple sequence repeat and indel markers developed from various citrus genome sequence resources. Parentage tests with 122 known hybrids using the selected DNA markers certify their transferability among those hybrids. Identity tests confirm that most variant strains are selected mutants, but we find four types of kunenbo (Citrus nobilis) and three types of tachibana (Citrus tachibana) for which we suggest different origins. Structure analysis with DNA markers that are in Hardy-Weinberg equilibrium deduce three basic taxa coinciding with the current understanding of citrus ancestors. Genotyping analysis of 101 indigenous citrus varieties with 123 selected DNA markers infers the parentages of 22 indigenous citrus varieties including Satsuma, Temple, and iyo, and single parents of 45 indigenous citrus varieties, including kunenbo, C. ichangensis, and Ichang lemon by allele-sharing and parentage tests. Genotyping analysis of chloroplast and mitochondrial genomes using 11 DNA markers classifies their cytoplasmic genotypes into 18 categories and deduces the combination of seed and pollen parents. Likelihood ratio analysis verifies the inferred parentages with significant scores. The reconstructed genealogy identifies 12 types of varieties consisting of Kishu, kunenbo, yuzu, koji, sour orange, dancy, kobeni mikan, sweet orange, tachibana, Cleopatra, willowleaf mandarin, and pummelo, which have played pivotal roles in the occurrence of these indigenous varieties. The inferred parentage of the indigenous varieties confirms their hybrid origins, as found by recent studies.
Kitajima, Akira; Nonaka, Keisuke; Yoshioka, Terutaka; Ohta, Satoshi; Goto, Shingo; Toyoda, Atsushi; Fujiyama, Asao; Mochizuki, Takako; Nagasaki, Hideki; Kaminuma, Eli; Nakamura, Yasukazu
2016-01-01
Most indigenous citrus varieties are assumed to be natural hybrids, but their parentage has so far been determined in only a few cases because of their wide genetic diversity and the low transferability of DNA markers. Here we infer the parentage of indigenous citrus varieties using simple sequence repeat and indel markers developed from various citrus genome sequence resources. Parentage tests with 122 known hybrids using the selected DNA markers certify their transferability among those hybrids. Identity tests confirm that most variant strains are selected mutants, but we find four types of kunenbo (Citrus nobilis) and three types of tachibana (Citrus tachibana) for which we suggest different origins. Structure analysis with DNA markers that are in Hardy–Weinberg equilibrium deduce three basic taxa coinciding with the current understanding of citrus ancestors. Genotyping analysis of 101 indigenous citrus varieties with 123 selected DNA markers infers the parentages of 22 indigenous citrus varieties including Satsuma, Temple, and iyo, and single parents of 45 indigenous citrus varieties, including kunenbo, C. ichangensis, and Ichang lemon by allele-sharing and parentage tests. Genotyping analysis of chloroplast and mitochondrial genomes using 11 DNA markers classifies their cytoplasmic genotypes into 18 categories and deduces the combination of seed and pollen parents. Likelihood ratio analysis verifies the inferred parentages with significant scores. The reconstructed genealogy identifies 12 types of varieties consisting of Kishu, kunenbo, yuzu, koji, sour orange, dancy, kobeni mikan, sweet orange, tachibana, Cleopatra, willowleaf mandarin, and pummelo, which have played pivotal roles in the occurrence of these indigenous varieties. The inferred parentage of the indigenous varieties confirms their hybrid origins, as found by recent studies. PMID:27902727
Ruan, Cheng-Jiang; Xu, Xue-Xuan; Shao, Hong-Bo; Jaleel, Cheruth Abdul
2010-09-01
In the past 20 years, the major effort in plant breeding has changed from quantitative to molecular genetics with emphasis on quantitative trait loci (QTL) identification and marker assisted selection (MAS). However, results have been modest. This has been due to several factors including absence of tight linkage QTL, non-availability of mapping populations, and substantial time needed to develop such populations. To overcome these limitations, and as an alternative to planned populations, molecular marker-trait associations have been identified by the combination between germplasm and the regression technique. In the present preview, the authors (1) survey the successful applications of germplasm-regression-combined (GRC) molecular marker-trait association identification in plants; (2) describe how to do the GRC analysis and its differences from mapping QTL based on a linkage map reconstructed from the planned populations; (3) consider the factors that affect the GRC association identification, including selections of optimal germplasm and molecular markers and testing of identification efficiency of markers associated with traits; and (4) finally discuss the future prospects of GRC marker-trait association analysis used in plant MAS/QTL breeding programs, especially in long-juvenile woody plants when no other genetic information such as linkage maps and QTL are available.
Automatic rice crop height measurement using a field server and digital image processing.
Sritarapipat, Tanakorn; Rakwatin, Preesan; Kasetkasem, Teerasit
2014-01-07
Rice crop height is an important agronomic trait linked to plant type and yield potential. This research developed an automatic image processing technique to detect rice crop height based on images taken by a digital camera attached to a field server. The camera acquires rice paddy images daily at a consistent time of day. The images include the rice plants and a marker bar used to provide a height reference. The rice crop height can be indirectly measured from the images by measuring the height of the marker bar compared to the height of the initial marker bar. Four digital image processing steps are employed to automatically measure the rice crop height: band selection, filtering, thresholding, and height measurement. Band selection is used to remove redundant features. Filtering extracts significant features of the marker bar. The thresholding method is applied to separate objects and boundaries of the marker bar versus other areas. The marker bar is detected and compared with the initial marker bar to measure the rice crop height. Our experiment used a field server with a digital camera to continuously monitor a rice field located in Suphanburi Province, Thailand. The experimental results show that the proposed method measures rice crop height effectively, with no human intervention required.
Identification of molecular markers associated with mite resistance in coconut (Cocos nucifera L.).
Shalini, K V; Manjunatha, S; Lebrun, P; Berger, A; Baudouin, L; Pirany, N; Ranganath, R M; Prasad, D Theertha
2007-01-01
Coconut mite (Aceria guerreronis 'Keifer') has become a major threat to Indian coconut (Coçcos nucifera L.) cultivators and the processing industry. Chemical and biological control measures have proved to be costly, ineffective, and ecologically undesirable. Planting mite-resistant coconut cultivars is the most effective method of preventing yield loss and should form a major component of any integrated pest management stratagem. Coconut genotypes, and mite-resistant and -susceptible accessions were collected from different parts of South India. Thirty-two simple sequence repeat (SSR) and 7 RAPD primers were used for molecular analyses. In single-marker analysis, 9 SSR and 4 RAPD markers associated with mite resistance were identified. In stepwise multiple regression analysis of SSRs, a combination of 6 markers showed 100% association with mite infestation. Stepwise multiple regression analysis for RAPD data revealed that a combination of 3 markers accounted for 83.86% of mite resistance in the selected materials. Combined stepwise multiple regression analysis of RAPD and SSR data showed that a combination of 5 markers explained 100% of the association with mite resistance in coconut. Markers associated with mite resistance are important in coconut breeding programs and will facilitate the selection of mite-resistant plants at an early stage as well as mother plants for breeding programs.
Petoumenos, Kathy; Huang, Robin; Hoy, Jennifer; Bloch, Mark; Templeton, David J; Baker, David; Giles, Michelle; Law, Matthew G; Cooper, David A
2017-01-01
In Australia, almost half of HIV-positive people are now aged over 50 and are predominately gay and bisexual men (GBM). Compared to the general HIV-negative population, GBM engage more in behaviours that may increase the risk of age-related comorbidities, including smoking, high alcohol consumption and recreational drug use. The objective of APPLES was to compare comorbidities and risk factors in HIV-positive older GBM with an appropriate control group of HIV-negative GBM. We undertook a prospectively recruited cross-sectional sample of HIV-positive and HIV-negative GBM ≥ 55 years. Detailed data collection included clinic data, a health and lifestyle survey, and blood sample collection. We report key demographic, laboratory markers and self-reported comorbidities by HIV status. For selected comorbidities we also adjust HIV status a priori for age, smoking and body mass index. Over 16 months 228 HIV-positive and 218 HIV-negative men were recruited. Median age was 63 years (IQR: 59-67). Although more HIV-positive men reported having ever smoked, smoking status was not statistically different between HIV positive and HIV negative men (p = 0.081). Greater alcohol use was reported by HIV-negative men (p = 0.002), and recreational drug use reported more often by HIV-positive men (p<0.001). After adjustment, HIV-positive men had significantly increased odds of diabetes (adjusted Odds ratio (aOR): 1.97, p = 0.038), thrombosis (aOR: 3.08, p = 0.007), neuropathy (aOR: 34.6, P<0.001), and non-significantly increased odds for heart-disease (aOR: 1.71, p = 0.077). In conclusion, HIV-positive GBM have significantly increased odds for key self-reported comorbidities. This study underscores the importance of an appropriate HIV-negative control group for more accurate evaluation of the risk and attribution of age-related comorbidities in HIV-positive people.
Uddowla, Sabena; Hollister, Jason; Pacheco, Juan M.; Rodriguez, Luis L.
2012-01-01
Vaccination of domestic animals with chemically inactivated foot-and-mouth disease virus (FMDV) is widely practiced to control FMD. Currently, FMD vaccine manufacturing requires the growth of large volumes of virulent FMDV in biocontainment-level facilities. Here, two marker FMDV vaccine candidates (A24LL3DYR and A24LL3BPVKV3DYR) featuring the deletion of the leader coding region (Lpro) and one of the 3B proteins were constructed and evaluated. These vaccine candidates also contain either one or two sets of mutations to create negative antigenic markers in the 3D polymerase (3Dpol) and 3B nonstructural proteins. Two mutations in 3Dpol, H27Y and N31R, as well as RQKP9-12→PVKV substitutions, in 3B2 abolish reactivity with monoclonal antibodies targeting the respective sequences in 3Dpol and 3B. Infectious cDNA clones encoding the marker viruses also contain unique restriction endonuclease sites flanking the capsid-coding region that allow for easy derivation of custom designed vaccine candidates. In contrast to the parental A24WT virus, single A24LL3DYR and double A24LL3BPVKV3DYR mutant viruses were markedly attenuated upon inoculation of cattle using the natural aerosol or direct tongue inoculation. Likewise, pigs inoculated with live A24LL3DYR virus in the heel bulbs showed no clinical signs of disease, no fever, and no FMD transmission to in-contact animals. Immunization of cattle with chemically inactivated A24LL3DYR and A24LL3BPVKV3DYR vaccines provided 100% protection from challenge with parental wild-type virus. These attenuated, antigenically marked viruses provide a safe alternative to virulent strains for FMD vaccine manufacturing. In addition, a competitive enzyme-linked immunosorbent assay targeted to the negative markers provides a suitable companion test for differentiating infected from vaccinated animals. PMID:22915802
High degree of genetic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus).
Defaveri, Jacquelin; Shikano, Takahito; Shimada, Yukinori; Merilä, Juha
2013-09-01
Populations of widespread marine organisms are typically characterized by a low degree of genetic differentiation in neutral genetic markers, but much less is known about differentiation in genes whose functional roles are associated with specific selection regimes. To uncover possible adaptive population divergence and heterogeneous genomic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus), we used a candidate gene-based genome-scan approach to analyse variability in 138 microsatellite loci located within/close to (<6 kb) functionally important genes in samples collected from ten geographic locations. The degree of genetic differentiation in markers classified as neutral or under balancing selection-as determined with several outlier detection methods-was low (F(ST) = 0.033 or 0.011, respectively), whereas average FST for directionally selected markers was significantly higher (F(ST) = 0.097). Clustering analyses provided support for genomic and geographic heterogeneity in selection: six genetic clusters were identified based on allele frequency differences in the directionally selected loci, whereas four were identified with the neutral loci. Allelic variation in several loci exhibited significant associations with environmental variables, supporting the conjecture that temperature and salinity, but not optic conditions, are important drivers of adaptive divergence among populations. In general, these results suggest that in spite of the high degree of physical connectivity and gene flow as inferred from neutral marker genes, marine stickleback populations are strongly genetically structured in loci associated with functionally relevant genes. © 2013 John Wiley & Sons Ltd.
Castaneto, Marisol S.; Scheidweiler, Karl B.; Gandhi, Adarsh; Wohlfarth, Ariane; Klette, Kevin L.; Martin, Thomas M.; Huestis, Marilyn A.
2014-01-01
Synthetic cannabinoid intake is an ongoing health issue worldwide, with new compounds continually emerging, making drug testing complex. Parent synthetic cannabinoids are rarely detected in urine, the most common matrix employed in workplace drug testing. Optimal identification of synthetic cannabinoid markers in authentic urine specimens and correlation of metabolite concentrations and toxicities would improve synthetic cannabinoid result interpretation. We screened 20,017 randomly collected US military urine specimens between July 2011 and June 2012 with a synthetic cannabinoid immunoassay yielding 1,432 presumptive positive specimens. We analyzed all presumptive positive and 1,069 negative specimens with our qualitative synthetic cannabinoid LC-MS/MS method, which confirmed 290 positive specimens. All 290 positive and 487 randomly-selected negative specimens were quantified with the most comprehensive urine quantitative LC-MS/MS method published to date. 290 specimens confirmed positive for 22 metabolites from 11 parent synthetic cannabinoids. The five most predominant metabolites were JWH-018 pentanoic acid (93%), JWH-018 N-hydroxypentyl (84%), AM2201 N-hydroxypentyl (69%), JWH-073 butanoic acid (69%), and JWH-122 N-hydroxypentyl (45%) with 11.1 (0.1–2434), 5.1 (0.1–1239), 2.0 (0.1–321), 1.1 (0.1–48.6), and 1.1 (0.1–250) μg/L median (range) concentrations, respectively. Alkyl hydroxy and carboxy metabolites provided suitable biomarkers for 11 parent synthetic cannabinoids; although, hydroxyindoles also were observed. This is by far the largest data set of synthetic cannabinoid metabolites urine concentrations from randomly collected workplace drug testing specimens rather than acute intoxications or driving under the influence of drugs. These data improve the interpretation of synthetic cannabinoid urine test results and suggest suitable urine markers of synthetic cannabinoid intake. PMID:25231213
Effects of neck bands on survival of greater snow geese
Menu, S.; Hestbeck, J.B.; Gauthier, G.; Reed, A.
2000-01-01
Neck bands are a widely used marker in goose research. However, few studies have investigated a possible negative effect of this marker on survival. We tested the effect of neck bands on the survival of adult female greater snow geese (Chen caerulescens atlantica) by marking birds with either a neck band and a metal leg band or a leg band only on Bylot Island (Nunavut, formerly included in the Northwest Territories, Canada) from 1990 to 1996. Annual survival was estimated using leg-band recoveries in fall and winter and using neck-band sightings in spring and fall. Recapture rates were estimated using summer recaptures. Using recovery data, the selected model yielded a survival similar for the neck-banded and leg-banded only birds (S = 0.845 ?? 0.070 vs. S = 0.811 ?? 0.107). The hypothesis of equality of survival between the 2 groups was easily accepted under most constraints imposed on survival or recovery rates. However, failure to account for a different direct recovery rate for neck-banded birds would lead us to incorrectly conclude a possible negative effect of neck bands on survival. Using sighting data, mean annual survival of neck-banded birds was independently estimated at 0.833 ?? 0.057, a value very similar to that estimated with band-recovery analysis. Raw recapture rates during summer were significantly lower for neck-banded birds compared to those marked with leg bands only (4.6% vs. 12.1%), but in this analysis, survival, site fidelity, reproductive status, and recapture rates were confounded. We conclude that neck bands did not affect survival of greater snow geese, but could possibly affect other demographic traits such as breeding propensity and emigration.
2010-01-01
Background Discrimination between clinical and environmental strains within many bacterial species is currently underexplored. Genomic analyses have clearly shown the enormous variability in genome composition between different strains of a bacterial species. In this study we have used Legionella pneumophila, the causative agent of Legionnaire's disease, to search for genomic markers related to pathogenicity. During a large surveillance study in The Netherlands well-characterized patient-derived strains and environmental strains were collected. We have used a mixed-genome microarray to perform comparative-genome analysis of 257 strains from this collection. Results Microarray analysis indicated that 480 DNA markers (out of in total 3360 markers) showed clear variation in presence between individual strains and these were therefore selected for further analysis. Unsupervised statistical analysis of these markers showed the enormous genomic variation within the species but did not show any correlation with a pathogenic phenotype. We therefore used supervised statistical analysis to identify discriminating markers. Genetic programming was used both to identify predictive markers and to define their interrelationships. A model consisting of five markers was developed that together correctly predicted 100% of the clinical strains and 69% of the environmental strains. Conclusions A novel approach for identifying predictive markers enabling discrimination between clinical and environmental isolates of L. pneumophila is presented. Out of over 3000 possible markers, five were selected that together enabled correct prediction of all the clinical strains included in this study. This novel approach for identifying predictive markers can be applied to all bacterial species, allowing for better discrimination between strains well equipped to cause human disease and relatively harmless strains. PMID:20630115
Stem Cell Therapy for Healing Wounded Skin and Soft Tissues
2012-07-01
changes of ASC surface markers due to repetitive in vitro sub-culturing. ASCs were harvested, washed in PBS to remove cell culture medium, and resuspended...Our in vitro and in vivo studies suggest that ASC and BM-MSC are not identical, though they have similar surface markers . We found that topically...ofpolybrene. Transduced cells were selected by treating 10 J.!g/rnl ofblasticidin. GFP expressing cells were further selected by flow cytometry using
Elkot, Ahmed Fawzy Abdelnaby; Chhuneja, Parveen; Kaur, Satinder; Saluja, Manny; Keller, Beat; Singh, Kuldeep
2015-01-01
Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici, is one of the important wheat diseases, worldwide. Two PM resistance genes, designated as PmTb7A.1 and PmTb7A.2, were identified in T. boeoticum acc. pau5088 and mapped on chromosome 7AL approximately 48cM apart. Two resistance gene analogue (RGA)-STS markers Ta7AL-4556232 and 7AL-4426363 were identified to be linked to the PmTb7A.1 and PmTb7A.2, at a distance of 0.6cM and 6.0cM, respectively. In the present study, following marker assisted selection (MAS), the two genes were transferred to T. aestivum using T. durum as bridging species. As many as 12,317 florets of F1 of the cross T. durum /T. boeoticum were pollinated with T. aestivum lines PBW343-IL and PBW621 to produce 61 and 65 seeds, respectively, of three-way F1. The resulting F1s of the cross T. durum/T. boeoticum//T. aestivum were screened with marker flanking both the PM resistance genes PmTb7A.1 and PmTb7A.2 (foreground selection) and the selected plants were backcrossed to generate BC1F1. Marker assisted selection was carried both in BC1F1 and the BC2F1 generations. Introgression of alien chromatin in BC2F1 plants varied from 15.4 - 62.9 percent. Out of more than 110 BC2F1 plants showing introgression for markers linked to the two PM resistance genes, 40 agronomically desirable plants were selected for background selection for the carrier chromosome to identify the plants with minimum of the alien introgression. Cytological analysis showed that most plants have chromosome number ranging from 40-42. The BC2F2 plants homozygous for the two genes have been identified. These will be crossed to generate lines combining both the PM resistance genes but with minimal of the alien introgression. The PM resistance gene PmTb7A.1 maps in a region very close to Sr22, a stem rust resistance gene effective against the race Ug99. Analysis of selected plants with markers linked to Sr22 showed introgression of Sr22 from T. boeoticum in several BC2F1 plants. Thus, in addition to PM resistance, these progeny might also carry resistance to stem rust race Ug99. PMID:26066332
Sequencing consolidates molecular markers with plant breeding practice.
Yang, Huaan; Li, Chengdao; Lam, Hon-Ming; Clements, Jonathan; Yan, Guijun; Zhao, Shancen
2015-05-01
Plenty of molecular markers have been developed by contemporary sequencing technologies, whereas few of them are successfully applied in breeding, thus we present a review on how sequencing can facilitate marker-assisted selection in plant breeding. The growing global population and shrinking arable land area require efficient plant breeding. Novel strategies assisted by certain markers have proven effective for genetic gains. Fortunately, cutting-edge sequencing technologies bring us a deluge of genomes and genetic variations, enlightening the potential of marker development. However, a large gap still exists between the potential of molecular markers and actual plant breeding practices. In this review, we discuss marker-assisted breeding from a historical perspective, describe the road from crop sequencing to breeding, and highlight how sequencing facilitates the application of markers in breeding practice.
Effect of promoter driving selectable marker on corn transformation.
Prakash, N Shiva; Prasad, V; Chidambram, Thillai P; Cherian, Shoba; Jayaprakash, T L; Dasgupta, Santanu; Wang, Qi; Mann, Michael T; Spencer, T Michael; Boddupalli, Raghava S
2008-08-01
Identification of an appropriate selection agent and its corresponding selectable marker gene is one of the first steps in establishing a transformation protocol for a given plant species. As the promoter controls expression level of the genes, the promoter driving the selectable marker gene can affect transformation. However, investigations into the direct effect of promoters driving selectable marker on transformation are lacking in the literature though many reports of relative strengths of promoters driving reporter genes like GUS or CAT or GFP are available. In the present study, we have compared rice Actin1 and CaMV.35S (commonly used promoters in monocotyledonous plant transformation) promoters driving nptII for their effectiveness in paromomycin selection of transgenic corn events. To enable statistically meaningful analysis of the results, a large sample size of nearly 5,000 immature embryos (explants) was employed producing approximately 1,250 independent events from each of the two constructs in four independent experiments. The rate of appearance of resistant calli and percentage of resistant calli recovered was higher with P-Os.Actin1/nptII/nos3' as compared to P-CaMV.35S/nptII/nos3' in all four experiments. There was no appreciable difference either in the frequency of plant regeneration or in the morphological characteristics of plants recovered from the two constructs. Although the escape rate trended lower with P-Os.Actin1 as compared to P-CaMV.35S, the recovery of low copy events was significantly higher with P-CaMV.35S. The higher transformation frequency with P-Os.Actin1 could be related to the strength of this promoter as compared to P-CaMV.35S in the explants and/or calli. Based on these results, we infer that the promoter driving the selectable marker is an important factor to be considered while establishing a high throughput transformation protocol as it could not only influence the transformation frequency but also the copy number of the transgene in the recovered transgenics.
2015-01-01
Background Selection of the best oocyte for subsequent steps of fertilization and embryo transfer was shown to be the crucial step in human infertility treatment procedure. Oocyte selection using morphological criteria mainly Zona pellucida (ZP) has been the gold standard method in assisted reproductive technologies (ART) clinics, but this selection approach has limitations in terms of accuracy, objectivity and constancy. Recent studies using OMICs-based approaches have allowed the identification of key molecular markers that quantitatively and non-invasively predict the oocyte quality for higher pregnancy rates and efficient infertility treatment. These biomarkers are a valuable reinforcement of the morphological selection criteria widely used in in vitro fertilization (IVF) clinics. In this context, this study was designed to investigate the relationship between transcriptomic predictors of oocyte quality found by our group and the conventional morphological parameters of oocyte quality mainly the ZP birefringence. Results Microarray data revealed that 48 and 27 differentially expressed candidate genes in cumulus cells (CCs) were respectively overexpressed and underexpressed in the ZGP (Zona Good Pregnant) versus ZBNP (Zona Bad Non Pregnant) groups. More than 70% of previously reported transcriptomic biomarkers of oocyte developmental competence were confirmed in this study. The analysis of possible association between ZP birefringence versus molecular markers approach showed an absence of correlation between them using the current set of markers. Conclusions This study suggested a new integrative approach that matches morphological and molecular approaches used to select developmentally competent oocytes able to lead to successful pregnancy and the delivery of healthy baby. For each ZP birefringence score, oocytes displayed a particular CCs' gene expression pattern. However, no correlations were found between the 7 gene biomarkers of oocyte developmental potential and the ZP birefringence score. Further studies using larger lists of candidate markers are required to identify suitable genes that are highly correlated with the morphological criteria, and therefore able to reinforce the accuracy of oocyte selection and the effectiveness of infertility treatment. PMID:25923296
Saturation of an intra-gene pool linkage map: toward unified consensus linkage map in common bean
USDA-ARS?s Scientific Manuscript database
Map-based cloning to find genes of interest and marker assisted selection (MAS) requires good genetic maps with high reproducible markers. In this study, we saturated the linkage map of the intra-gene pool population of common bean DOR364×BAT477 (DB) by evaluating 2,706 molecular markers in includin...
Liston, Adrian; Hardy, Kristine; Pittelkow, Yvonne; Wilson, Susan R; Makaroff, Lydia E; Fahrer, Aude M; Goodnow, Christopher C
2007-01-01
T cells in the thymus undergo opposing positive and negative selection processes so that the only T cells entering circulation are those bearing a T cell receptor (TCR) with a low affinity for self. The mechanism differentiating negative from positive selection is poorly understood, despite the fact that inherited defects in negative selection underlie organ-specific autoimmune disease in AIRE-deficient people and the non-obese diabetic (NOD) mouse strain Here we use homogeneous populations of T cells undergoing either positive or negative selection in vivo together with genome-wide transcription profiling on microarrays to identify the gene expression differences underlying negative selection to an Aire-dependent organ-specific antigen, including the upregulation of a genomic cluster in the cytogenetic band 2F. Analysis of defective negative selection in the autoimmune-prone NOD strain demonstrates a global impairment in the induction of the negative selection response gene set, but little difference in positive selection response genes. Combining expression differences with genetic linkage data, we identify differentially expressed candidate genes, including Bim, Bnip3, Smox, Pdrg1, Id1, Pdcd1, Ly6c, Pdia3, Trim30 and Trim12. The data provide a molecular map of the negative selection response in vivo and, by analysis of deviations from this pathway in the autoimmune susceptible NOD strain, suggest that susceptibility arises from small expression differences in genes acting at multiple points in the pathway between the TCR and cell death.
Liston, Adrian; Hardy, Kristine; Pittelkow, Yvonne; Wilson, Susan R; Makaroff, Lydia E; Fahrer, Aude M; Goodnow, Christopher C
2007-01-01
Background T cells in the thymus undergo opposing positive and negative selection processes so that the only T cells entering circulation are those bearing a T cell receptor (TCR) with a low affinity for self. The mechanism differentiating negative from positive selection is poorly understood, despite the fact that inherited defects in negative selection underlie organ-specific autoimmune disease in AIRE-deficient people and the non-obese diabetic (NOD) mouse strain Results Here we use homogeneous populations of T cells undergoing either positive or negative selection in vivo together with genome-wide transcription profiling on microarrays to identify the gene expression differences underlying negative selection to an Aire-dependent organ-specific antigen, including the upregulation of a genomic cluster in the cytogenetic band 2F. Analysis of defective negative selection in the autoimmune-prone NOD strain demonstrates a global impairment in the induction of the negative selection response gene set, but little difference in positive selection response genes. Combining expression differences with genetic linkage data, we identify differentially expressed candidate genes, including Bim, Bnip3, Smox, Pdrg1, Id1, Pdcd1, Ly6c, Pdia3, Trim30 and Trim12. Conclusion The data provide a molecular map of the negative selection response in vivo and, by analysis of deviations from this pathway in the autoimmune susceptible NOD strain, suggest that susceptibility arises from small expression differences in genes acting at multiple points in the pathway between the TCR and cell death. PMID:17239257
Investigating a memory-based account of negative priming: support for selection-feature mismatch.
MacDonald, P A; Joordens, S
2000-08-01
Using typical and modified negative priming tasks, the selection-feature mismatch account of negative priming was tested. In the modified task, participants performed selections on the basis of a semantic feature (e.g., referent size). This procedure has been shown to enhance negative priming (P. A. MacDonald, S. Joordens, & K. N. Seergobin, 1999). Across 3 experiments, negative priming occurred only when the repeated item mismatched in terms of the feature used as the basis for selections. When the repeated item was congruent on the selection feature across the prime and probe displays, positive priming arose. This pattern of results appeared in both the ignored- and the attended-repetition conditions. Negative priming does not result from previously ignoring an item. These findings strongly support the selection-feature mismatch account of negative priming and refute both the distractor inhibition and the episodic-retrieval explanations.
Xu, Shuhua
2015-01-01
Noncoding DNA sequences (NCS) have attracted much attention recently due to their functional potentials. Here we attempted to reveal the functional roles of noncoding sequences from the point of view of natural selection that typically indicates the functional potentials of certain genomic elements. We analyzed nearly 37 million single nucleotide polymorphisms (SNPs) of Phase I data of the 1000 Genomes Project. We estimated a series of key parameters of population genetics and molecular evolution to characterize sequence variations of the noncoding genome within and between populations, and identified the natural selection footprints in NCS in worldwide human populations. Our results showed that purifying selection is prevalent and there is substantial constraint of variations in NCS, while positive selectionis more likely to be specific to some particular genomic regions and regional populations. Intriguingly, we observed larger fraction of non-conserved NCS variants with lower derived allele frequency in the genome, indicating possible functional gain of non-conserved NCS. Notably, NCS elements are enriched for potentially functional markers such as eQTLs, TF motif, and DNase I footprints in the genome. More interestingly, some NCS variants associated with diseases such as Alzheimer's disease, Type 1 diabetes, and immune-related bowel disorder (IBD) showed signatures of positive selection, although the majority of NCS variants, reported as risk alleles by genome-wide association studies, showed signatures of negative selection. Our analyses provided compelling evidence of natural selection forces on noncoding sequences in the human genome and advanced our understanding of their functional potentials that play important roles in disease etiology and human evolution. PMID:26053627
Genome-wide DNA polymorphisms in two cultivars of mei (Prunus mume sieb. et zucc.).
Sun, Lidan; Zhang, Qixiang; Xu, Zongda; Yang, Weiru; Guo, Yu; Lu, Jiuxing; Pan, Huitang; Cheng, Tangren; Cai, Ming
2013-10-06
Mei (Prunus mume Sieb. et Zucc.) is a famous ornamental plant and fruit crop grown in East Asian countries. Limited genetic resources, especially molecular markers, have hindered the progress of mei breeding projects. Here, we performed low-depth whole-genome sequencing of Prunus mume 'Fenban' and Prunus mume 'Kouzi Yudie' to identify high-quality polymorphic markers between the two cultivars on a large scale. A total of 1464.1 Mb and 1422.1 Mb of 'Fenban' and 'Kouzi Yudie' sequencing data were uniquely mapped to the mei reference genome with about 6-fold coverage, respectively. We detected a large number of putative polymorphic markers from the 196.9 Mb of sequencing data shared by the two cultivars, which together contained 200,627 SNPs, 4,900 InDels, and 7,063 SSRs. Among these markers, 38,773 SNPs, 174 InDels, and 418 SSRs were distributed in the 22.4 Mb CDS region, and 63.0% of these marker-containing CDS sequences were assigned to GO terms. Subsequently, 670 selected SNPs were validated using an Agilent's SureSelect solution phase hybridization assay. A subset of 599 SNPs was used to assess the genetic similarity of a panel of mei germplasm samples and a plum (P. salicina) cultivar, producing a set of informative diversity data. We also analyzed the frequency and distribution of detected InDels and SSRs in mei genome and validated their usefulness as DNA markers. These markers were successfully amplified in the cultivars and in their segregating progeny. A large set of high-quality polymorphic SNPs, InDels, and SSRs were identified in parallel between 'Fenban' and 'Kouzi Yudie' using low-depth whole-genome sequencing. The study presents extensive data on these polymorphic markers, which can be useful for constructing high-resolution genetic maps, performing genome-wide association studies, and designing genomic selection strategies in mei.
Even-Desrumeaux, Klervi; Nevoltris, Damien; Lavaut, Marie Noelle; Alim, Karima; Borg, Jean-Paul; Audebert, Stéphane; Kerfelec, Brigitte; Baty, Daniel; Chames, Patrick
2014-01-01
Phage display is a well-established procedure to isolate binders against a wide variety of antigens that can be performed on purified antigens, but also on intact cells. As selection steps are performed in vitro, it is possible to focus the outcome of the selection on relevant epitopes by performing some additional steps, such as depletion or competitive elutions. However in practice, the efficiency of these steps is often limited and can lead to inconsistent results. We have designed a new selection method named masked selection, based on the blockade of unwanted epitopes to favor the targeting of relevant ones. We demonstrate the efficiency and flexibility of this method by selecting single-domain antibodies against a specific portion of a fusion protein, by selecting binders against several members of the seven transmembrane receptor family using transfected HEK cells, or by selecting binders against unknown breast cancer markers not expressed on normal samples. The relevance of this approach for antibody-based therapies was further validated by the identification of four of these markers, Epithelial cell adhesion molecule, Transferrin receptor 1, Metastasis cell adhesion molecule, and Sushi containing domain 2, using immunoprecipitation and mass spectrometry. This new phage display strategy can be applied to any type of antibody fragments or alternative scaffolds, and is especially suited for the rapid discovery and identification of cell surface markers. PMID:24361863
Liu, Huidi; Yan, Yan; Wen, Haixia; Jiang, Xueli; Cao, Xuefeng; Zhang, Guangmei; Liu, Guoyi
2014-05-01
G protein-coupled estrogen receptor (GPER) is recently identified as a membrane-associated estrogen receptor that mediates non-genomic effects of estrogen. Our previous immunohistochemistry study found an association between GPER and the proliferation of epithelial ovarian cancer. However, the contributions and mechanisms of GPER in the proliferation of ovarian cancers are not clear. We have examined the role of GPER in estrogen receptor α (ERα)-negative/GPER positive OVCAR5 ovarian cancer cell line. MTT assay was used to detect cell proliferation. BrdU incorporation assay was used to measure the cells in S-phase. Protein expression of marker genes of proliferation, cell cycle and apoptosis were examined by Western blot. The results showed that 17β-estradiol and selective GPER agonist G-1 stimulated the proliferation of OVCAR5 cells and increased the cells in S-phase. Both ligands upregulated the protein levels of c-fos and cyclin D1. Small interfering RNA targeting GPER or G protein inhibitor pertussin toxin (PTX) inhibited basal cell proliferation and attenuated 17β-estradiol- or G-1-induced cell proliferation. GPER mediated cell growth was also associated with the apoptosis of OVCAR5 cells. These findings suggest that GPER has an important function in the proliferation of ovarian cancer cells lacking ERα. GPER might be a promising therapeutic target in ovarian cancer. © 2014 International Federation for Cell Biology.
Togo, Shinsaku; Katagiri, Nobuyoshi; Namba, Yukiko; Tulafu, Miniwan; Nagahama, Kumi; Kadoya, Kotarou; Takamochi, Kazuya; Oh, Siaki; Suzuki, Kenji; Sakurai, Fuminori; Mizuguchi, Hiroyuki; Urata, Yasuo; Takahashi, Kazuhisa
2017-01-01
Circulating tumor cells (CTCs) have a crucial role in the clinical outcome of cancer patients. Detection of non-small cell lung cancer (NSCLC) using an antibody against epithelial cell adhesion molecule (EpCAM) in captured CTCs has low sensitivity; the loss of epithelial markers leads to underestimation of CTCs with mesenchymal phenotype. We propose a new approach for detection of viable CTCs, including those with epithelial-mesenchymal transition status (EMT-CTCs), using the new telomerase-specific replication-selective adenovirus (OBP-1101), TelomeScan F35. Peripheral venous blood samples and clinicopathological data were collected from 123 NSCLC patients. The sensitivity of CTC detection was 69.1%, and for patients with stage I, II, III and IV, it was 59.6%, 40.0%, 85.7%, and 75.0%, respectively. Among the EMT-CTC samples, 46% were vimentin positive and 39.0% of non-EMT-CTC samples were EpCAM positive. Patients testing positive for EMT-CTCs at baseline had poor response to chemotherapy (P = 0.025) and decreased progression-free survival (EMT-CTC positive vs. negative: 193 ± 47 days vs. 388 ± 47. days, P = 0.040) in comparison to those testing negative. TelomeScan F35 is a highly sensitive CTC detection system and will be a useful screening tool for early diagnosis of NSCLC patients. Mesenchymal-phenotype CTCs are crucial indicators of chemotherapeutic efficacy in NSCLC patients. PMID:28432274
Human papillomavirus-associated oropharynx cancer (HPV-OPC): treatment options.
Chau, Nicole G; Rabinowits, Guilherme; Haddad, Robert I
2014-12-01
Human papillomavirus-associated oropharynx cancer (HPV-OPC) is growing in incidence and has distinct clinical, pathologic, molecular, and epidemiologic features. However, the management of HPV-OPC does not presently differ from HPV-negative OPC based on the current evidence and requires complex multidisciplinary approaches. The superior prognosis of HPV-OPC and the toxicities of current multimodality treatment in a young population serve as the impetus to evaluate de-intensification treatment regimens aimed at reducing toxicity while maintaining therapeutic efficacy. Clinical trials are underway to evaluate reduced doses of radiation or less toxic systemic therapy regimens in HPV-OPC. Minimally invasive surgical approaches in the HPV-OPC population with early tumor stage also are being investigated. De-intensification strategies should only be employed in the context of clinical trials, and HPV-OPC patients should be offered clinical trials' participation. Appropriate patient selection is critical to the development of de-intensification regimens, and this requires greater understanding of risk factors within the HPV-OPC population, HPV-OPC biology, and how HPV modulates response to specific therapies. Smoking history and bulky nodal disease have been shown to impact negatively the favorable prognosis of HPV association. Validated biomarkers within the HPV-OPC population are lacking, although alterations in the PI3K pathway and markers of immune response may emerge as important considerations in the future. Novel therapeutic strategies are desperately needed particularly for HPV-OPC patients who fail definitive therapy, and select patients with recurrent or metastatic disease may benefit from aggressive approaches.
Togo, Shinsaku; Katagiri, Nobuyoshi; Namba, Yukiko; Tulafu, Miniwan; Nagahama, Kumi; Kadoya, Kotarou; Takamochi, Kazuya; Oh, Siaki; Suzuki, Kenji; Sakurai, Fuminori; Mizuguchi, Hiroyuki; Urata, Yasuo; Takahashi, Kazuhisa
2017-05-23
Circulating tumor cells (CTCs) have a crucial role in the clinical outcome of cancer patients. Detection of non-small cell lung cancer (NSCLC) using an antibody against epithelial cell adhesion molecule (EpCAM) in captured CTCs has low sensitivity; the loss of epithelial markers leads to underestimation of CTCs with mesenchymal phenotype. We propose a new approach for detection of viable CTCs, including those with epithelial-mesenchymal transition status (EMT-CTCs), using the new telomerase-specific replication-selective adenovirus (OBP-1101), TelomeScan F35. Peripheral venous blood samples and clinicopathological data were collected from 123 NSCLC patients. The sensitivity of CTC detection was 69.1%, and for patients with stage I, II, III and IV, it was 59.6%, 40.0%, 85.7%, and 75.0%, respectively. Among the EMT-CTC samples, 46% were vimentin positive and 39.0% of non-EMT-CTC samples were EpCAM positive. Patients testing positive for EMT-CTCs at baseline had poor response to chemotherapy (P = 0.025) and decreased progression-free survival (EMT-CTC positive vs. negative: 193 ± 47 days vs. 388 ± 47. days, P = 0.040) in comparison to those testing negative. TelomeScan F35 is a highly sensitive CTC detection system and will be a useful screening tool for early diagnosis of NSCLC patients. Mesenchymal-phenotype CTCs are crucial indicators of chemotherapeutic efficacy in NSCLC patients.
The contribution of diet and genotype to iron status in women: a classical twin study.
Fairweather-Tait, Susan J; Guile, Geoffrey R; Valdes, Ana M; Wawer, Anna A; Hurst, Rachel; Skinner, Jane; Macgregor, Alexander J
2013-01-01
This is the first published report examining the combined effect of diet and genotype on body iron content using a classical twin study design. The aim of this study was to determine the relative contribution of genetic and environmental factors in determining iron status. The population was comprised of 200 BMI- and age-matched pairs of MZ and DZ healthy twins, characterised for habitual diet and 15 iron-related candidate genetic markers. Variance components analysis demonstrated that the heritability of serum ferritin (SF) and soluble transferrin receptor was 44% and 54% respectively. Measured single nucleotide polymorphisms explained 5% and selected dietary factors 6% of the variance in iron status; there was a negative association between calcium intake and body iron (p = 0.02) and SF (p = 0.04).
Clinical uses of brain natriuretic peptide in diagnosing and managing heart failure.
Anderson, Kelley M
2008-06-01
To review current issues in the diagnosis, prognosis, and management of heart failure (HF), focusing on the clinical use of brain natriuretic peptide (BNP) as a diagnostic marker. Selective review of scientific literature and clinical practice guidelines. BNP is a useful clinical tool for the diagnosis, prognosis, and management of HF patients. Studies have consistently demonstrated high sensitivity, specificity, and negative predictive value of BNP levels in diagnostic situations. BNP cannot differentiate between systolic and diastolic HF. BNP can be used to assist in diagnosing HF in emergency and outpatient situations, particularly when the presenting symptom is dyspnea; determining HF prognosis, including predicting death and cardiac events; and potentially managing individuals with HF by determining safe discharge levels from acute care to avoid readmissions. BNP levels can vary depending on multiple confounders; therefore, clinical interpretation can be difficult.
Ion-exchange chromatography purification of extracellular vesicles.
Kosanović, Maja; Milutinović, Bojana; Goč, Sanja; Mitić, Ninoslav; Janković, Miroslava
2017-08-01
Despite numerous studies, isolating pure preparations of extracellular vesicles (EVs) has proven challenging. Here, we compared ion-exchange chromatography (IEC) to the widely used sucrose density gradient (SDG) centrifugation method for the purification of EVs. EVs in bulk were isolated from pooled normal human amniotic fluid (AF) by differential centrifugation followed by IEC or sucrose density gradient separation. The purity of the isolated EVs was evaluated by electrophoresis and lectin blotting/immuno blotting to monitor the distribution of total proteins, different EVs markers, and selected N-glycans. Our data showed efficient separation of negatively charged EVs from other differently charged molecules, while comparative profiling of EVs using SDG centrifugation confirmed anion-exchange chromatography is advantageous for EV purification. Finally, although this IEC-based method was validated using AF, the approach should be readily applicable to isolation of EVs from other sources as well.
Bennett, G L; Shackelford, S D; Wheeler, T L; King, D A; Casas, E; Smith, T P L
2013-02-01
Genetic markers in casein (CSN1S1) and thyroglobulin (TG) genes have previously been associated with fat distribution in cattle. Determining the nature of these genetic associations (additive, recessive, or dominant) has been difficult, because both markers have small minor allele frequencies in most beef cattle populations. This results in few animals homozygous for the minor alleles. selection to increase the frequencies of the minor alleles for 2 SNP markers in these genes was undertaken in a composite population. The objective was to obtain better estimates of genetic effects associated with these markers and determine if there were epistatic interactions. Selection increased the frequencies of minor alleles for both SNP from <0.30 to 0.45. Bulls (n = 24) heterozygous for both SNP were used in 3 yr to produce 204 steer progeny harvested at an average age of 474 d. The combined effect of the 9 CSN1S1 × TG genotypes was associated with carcass-adjusted fat thickness (P < 0.06) and meat tenderness predicted at the abattoir by visible and near-infrared reflectance spectroscopy (P < 0.04). Genotype did not affect BW from birth through harvest, ribeye area, marbling score, slice shear force, or image-based yield grade (P > 0.10). Additive, dominance, and epistatic SNP association effects were estimated from genotypic effects for adjusted fat thickness and predicted meat tenderness. Adjusted fat thickness showed a dominance association with TG SNP (P < 0.06) and an epistatic additive CSN1S1 × additive TG association (P < 0.03). For predicted meat tenderness, heterozygous TG meat was more tender than meat from either homozygote (P < 0.002). Dominance and epistatic associations can result in different SNP allele substitution effects in populations where SNP have the same linkage disequilibrium with causal mutations but have different frequencies. Although the complex associations estimated in this study would contribute little to within-population selection response, they could be important for marker-assisted management or reciprocal selection schemes.
ERIC Educational Resources Information Center
Thorne, John C.
2017-01-01
Purpose: The purpose of this study was to examine (a) whether increased grammatical error rates during a standardized narrative task are a more clinically useful marker of central nervous system abnormality in Fetal Alcohol Spectrum Disorders (FASD) than common measures of productivity or grammatical complexity and (b) whether combining the rate…
Parwani, Anil V; Marlow, Cameron; Demarzo, Angelo M; Mikolajczyk, Stephen D; Rittenhouse, Harry G; Veltri, Robert W; Chan, Theresa Y
2006-10-01
Precursors of prostate-specific antigen (proPSA) have been previously shown to be more concentrated in prostate cancer tissue. This study characterizes the immunohistochemical staining (IHS) of proPSA forms in metastatic prostate cancer compared with prostate specific antigen (PSA) and prostatic acid phosphatase (PAP). A tissue microarray, consisting of 74 cases of metastatic prostate carcinoma and control tissues, was used. IHS, using monoclonal antibodies against proPSA with a truncated proleader peptide containing 2 amino acids ([-2]pPSA), native ([-5/-7]pPSA), PSA, and PAP, was analyzed. The monoclonal antibodies were specific for both benign and malignant prostatic glandular tissue. IHS with [-5/-7]pPSA showed the least number of cases with negative staining (3%), and the most number of cases with moderate or strong staining (76%). In the 60 cases where all 4 stains could be evaluated, none of them were negative for proPSA and positive for PSA or PAP, and all 7 cases that were negative for both PSA and PAP showed IHS to proPSA. [-5/-7]pPSA (native proPSA) may be a better marker than PSA and PAP in characterizing metastatic prostate adenocarcinoma, with most of the cases showing positivity for the marker. Even cases that were negative for PSA and PAP, were reactive for proPSA. Such enhanced detection is particularly important in poorly differentiated carcinomas involving metastatic sites where prostate carcinoma is a consideration. A panel of markers, including proPSA, should be performed when metastatic prostate carcinoma is in the differential diagnosis.
Prognostic relevance of miR-137 in patients with hepatocellular carcinoma.
Sakabe, Tomohiko; Azumi, Junya; Umekita, Yoshihisa; Toriguchi, Kan; Hatano, Etsuro; Hirooka, Yasuaki; Shiota, Goshi
2017-02-01
Cancer stem cells (CSCs) play a pivotal role in progression, metastasis and recurrence of cancer. Therefore, it is clinically useful to identify the relevant CSC marker that is associated with prognosis of hepatocellular carcinoma (HCC) and clarify its genetic and biological characteristics. Expression of four CSC markers, CD13, EpCAM, CD44 and CD44v9, was examined in 99 HCC patients. Biological and cDNA/miRNA microarray data were compared among CD44-positive/-negative HCC cells and normal hepatic cells. The significance of the representative miRNAs was examined with regard to prognosis of additional 110 HCC patients. CD44-positive HuH7 cells proliferated faster and showed a greater sphere forming ability than CD44-negative HuH7 cells. CD44-positive HuH7 cells exhibited higher expression of specific genes involved in resistance to reactive oxygen species, anticancer drugs and tumour invasion than CD44-negative HCC cells. Higher expression of six miRNAs was observed in CD44-positive HuH7 cells, CD44-negative HuH7 cells, and human normal hepatic cells in that order. Of the six miRNAs, miR-137 was closely associated with overall and cancer-specific survivals, as well as with invasion of hepatic vein, hepatic artery, portal vein and bile duct, and alpha-foetoprotein in additional 110 HCC patients. miR-137 may serve as a prognostic marker in patients with HCC and may be a potential target for the elimination of liver CSCs. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Kwong, Qi Bin; Ong, Ai Ling; Teh, Chee Keng; Chew, Fook Tim; Tammi, Martti; Mayes, Sean; Kulaveerasingam, Harikrishna; Yeoh, Suat Hui; Harikrishna, Jennifer Ann; Appleton, David Ross
2017-06-06
Genomic selection (GS) uses genome-wide markers to select individuals with the desired overall combination of breeding traits. A total of 1,218 individuals from a commercial population of Ulu Remis x AVROS (UR x AVROS) were genotyped using the OP200K array. The traits of interest included: shell-to-fruit ratio (S/F, %), mesocarp-to-fruit ratio (M/F, %), kernel-to-fruit ratio (K/F, %), fruit per bunch (F/B, %), oil per bunch (O/B, %) and oil per palm (O/P, kg/palm/year). Genomic heritabilities of these traits were estimated to be in the range of 0.40 to 0.80. GS methods assessed were RR-BLUP, Bayes A (BA), Cπ (BC), Lasso (BL) and Ridge Regression (BRR). All methods resulted in almost equal prediction accuracy. The accuracy achieved ranged from 0.40 to 0.70, correlating with the heritability of traits. By selecting the most important markers, RR-BLUP B has the potential to outperform other methods. The marker density for certain traits can be further reduced based on the linkage disequilibrium (LD). Together with in silico breeding, GS is now being used in oil palm breeding programs to hasten parental palm selection.
P21, COX-2, and E-cadherin are potential prognostic factors for esophageal squamous cell carcinoma.
Lin, Yao; Shen, Lu-Yan; Fu, Hao; Dong, Bin; Yang, He-Li; Yan, Wan-Pu; Kang, Xiao-Zheng; Dai, Liang; Zhou, Hai-Tao; Yang, Yong-Bo; Liang, Zhen; Chen, Ke-Neng
2017-02-01
Much research effort has been devoted to identifying prognostic factors for esophageal squamous cell carcinoma (ESCC) by immunohistochemistry; however, no conclusive findings have been reached thus far. We hypothesized that certain molecules identified in previous studies might serve as useful prognostic markers for ESCC. Therefore, the aim of the current study was to validate the most relevant markers showing potential for ESCC prognosis in our prospective esophageal cancer database. A literature search was performed using the PubMed database for papers published between 1980 and 2015 using the following key words: 'esophageal cancer,' 'prognosis,' and 'immunohistochemistry.' Literature selection criteria were established to identify the most widely studied markers, and we further validated the selected markers in a cohort from our single-surgeon team, including 153 esophageal cancer patients treated from 2000 to 2010. A total of 1799 articles were identified, 82 of which met the selection criteria. Twelve markers were found to be the most widely studied, and the validation results indicated that only P21, COX-2, and E-cadherin were independent prognostic factors for ESCC patients in this series. The systemic review and cohort validation suggest that P21, COX-2, and E-cadherin are potential prognostic factors for ESCC, paving the way for more targeted prospective validation in the future. © 2016 International Society for Diseases of the Esophagus.
McElroy, Michel S; Navarro, Alberto J R; Mustiga, Guiliana; Stack, Conrad; Gezan, Salvador; Peña, Geover; Sarabia, Widem; Saquicela, Diego; Sotomayor, Ignacio; Douglas, Gavin M; Migicovsky, Zoë; Amores, Freddy; Tarqui, Omar; Myles, Sean; Motamayor, Juan C
2018-01-01
Cacao ( Theobroma cacao ) is a globally important crop, and its yield is severely restricted by disease. Two of the most damaging diseases, witches' broom disease (WBD) and frosty pod rot disease (FPRD), are caused by a pair of related fungi: Moniliophthora perniciosa and Moniliophthora roreri , respectively. Resistant cultivars are the most effective long-term strategy to address Moniliophthora diseases, but efficiently generating resistant and productive new cultivars will require robust methods for screening germplasm before field testing. Marker-assisted selection (MAS) and genomic selection (GS) provide two potential avenues for predicting the performance of new genotypes, potentially increasing the selection gain per unit time. To test the effectiveness of these two approaches, we performed a genome-wide association study (GWAS) and GS on three related populations of cacao in Ecuador genotyped with a 15K single nucleotide polymorphism (SNP) microarray for three measures of WBD infection (vegetative broom, cushion broom, and chirimoya pod), one of FPRD (monilia pod) and two productivity traits (total fresh weight of pods and % healthy pods produced). GWAS yielded several SNPs associated with disease resistance in each population, but none were significantly correlated with the same trait in other populations. Genomic selection, using one population as a training set to estimate the phenotypes of the remaining two (composed of different families), varied among traits, from a mean prediction accuracy of 0.46 (vegetative broom) to 0.15 (monilia pod), and varied between training populations. Simulations demonstrated that selecting seedlings using GWAS markers alone generates no improvement over selecting at random, but that GS improves the selection process significantly. Our results suggest that the GWAS markers discovered here are not sufficiently predictive across diverse germplasm to be useful for MAS, but that using all markers in a GS framework holds substantial promise in accelerating disease-resistance in cacao.
Marker-assisted breeding for introgression of opaque-2 allele into elite maize inbred line BML-7.
Krishna, M S R; Sokka Reddy, S; Satyanarayana, Sadam D V
2017-07-01
Improvement of quality protein maize (QPM) along with high content of lysine and tryptophan had foremost importance in maize breeding program. The efficient and easiest way of developing QPM hybrids was by backcross breeding in marker aided selection. Hence, the present investigation aimed at conversion of elite maize inbred line BML-7 into QPM line. CML-186 was identified to be a donor variety as it revealed high-quality polymorphism with BML-7 for opaque-2 gene specific marker umc1066. Non-QPM inbred line BML-7 was crossed with QPM donor CML-186 and produced F 1 followed by the development of BC 1 F 1 and BC 2 F 1 population. Foreground selection was carried out with umc1066 in F 1 , and selected plants were used for BC 1 F 1 and BC 2 F 1 populations. Two hundred plants were screened in both BC 1 F 1 and BC 2 F 1 population with umc1066 for foreground selection amino acid modifiers. Foreground selected plants for both opaque-2 and amino acid modifiers were screened for background selection for BML-7 genome. Recurrent parent genome (RPG) was calculated for BC 2 F 1 population plants. Two plants have shown with RPG 90-93% in two generation with back cross population. Two BC 2 F 2 populations resulted from marker recognized BC 2 F 1 individuals subjected toward foreground selection followed by tryptophan estimation. The tryptophan and lysine concentration was improved in all the plants. BC 2 F 2 lines developed from hard endosperm kernels were selfed for BC 2 F 2 lines and finest line was selected to illustrate the QPM version of BML-7, with 0.97% of tryptophan and 4.04% of lysine concentration in protein. Therefore, the QPM version of BML-7 line can be used for the development of single cross hybrid QPM maize version.
Steele, Katherine A; Quinton-Tulloch, Mark J; Amgai, Resham B; Dhakal, Rajeev; Khatiwada, Shambhu P; Vyas, Darshna; Heine, Martin; Witcombe, John R
2018-01-01
Few public sector rice breeders have the capacity to use NGS-derived markers in their breeding programmes despite rapidly expanding repositories of rice genome sequence data. They rely on > 18,000 mapped microsatellites (SSRs) for marker-assisted selection (MAS) using gel analysis. Lack of knowledge about target SNP and InDel variant loci has hampered the uptake by many breeders of Kompetitive allele-specific PCR (KASP), a proprietary technology of LGC genomics that can distinguish alleles at variant loci. KASP is a cost-effective single-step genotyping technology, cheaper than SSRs and more flexible than genotyping by sequencing (GBS) or array-based genotyping when used in selection programmes. Before this study, there were 2015 rice KASP marker loci in the public domain, mainly identified by array-based screening, leaving large proportions of the rice genome with no KASP coverage. Here we have addressed the urgent need for a wide choice of appropriate rice KASP assays and demonstrated that NGS can detect many more KASP to give full genome coverage. Through re-sequencing of nine indica rice breeding lines or released varieties, this study has identified 2.5 million variant sites. Stringent filtering of variants generated 1.3 million potential KASP assay designs, including 92,500 potential functional markers. This strategy delivers a 650-fold increase in potential selectable KASP markers at a density of 3.1 per 1 kb in the indica crosses analysed and 377,178 polymorphic KASP design sites on average per cross. This knowledge is available to breeders and has been utilised to improve the efficiency of public sector breeding in Nepal, enabling identification of polymorphic KASP at any region or quantitative trait loci in relevant crosses. Validation of 39 new KASP was carried out by genotyping progeny from a range of crosses to show that they detected segregating alleles. The new KASP have replaced SSRs to aid trait selection during marker-assisted backcrossing in these crosses, where target traits include rice blast and BLB resistance loci. Furthermore, we provide the software for plant breeders to generate KASP designs from their own datasets.
Peimani, Zeinab; Banihashemi, Mohammad Amin; Namazi, Niloofar; Monabati, Ahmad; Mojallal, Mehra; Borhani-Haghighi, Afshin
2014-01-01
Background Myasthenia gravis (MG) is an autoimmune disorder characterized by weakness and fatigability of skeletal muscles. The aim of this study was to determine if pathological characteristics in non-thymomatous patients of MG would correlate with prognosis in a three year follow up. Methods Patients who had had their thymectomy at least three years prior to the study were selected from three hospitals and were followed for 3 years. Prognosis was assessed via a devised prognostic scoring system. A pathological exam of the specimen from the thymus was done using the following immunohistochemical markers: Bcl2, CD 3, CD 4, CD 5, CD 7, CD 10, CD 20cy, CD 23, CD 43, and Ki67. Results Fifteen patients fulfilled the inclusion criteria and had a complete follow-up. This included 3 males and 12 females with a mean age of 36.6 years at the start of the study. The dominant cell population was T lymphocytes. All T cells expressed CD 3, CD 43, CD 5, and Bcl-2. In 2 patients, CD 10 marker was positive in T cells. B cells were negative for activation marker CD 23, except for germinal center dendritic cells. Due to the limited number of patients in the study, the power of the study would not allow for an analysis to assess correlation between histopathological data and prognosis. Conclusion This pilot study was an attempt to discover any prognostic indices from the histopathological examination of the resected thymic tissue in the patients with myasthenia gravis. PMID:24800046
Fungal Infection Increases the Rate of Somatic Mutation in Scots Pine (Pinus sylvestris L.).
Ranade, Sonali Sachin; Ganea, Laura-Stefana; Razzak, Abdur M; García Gil, M R
2015-01-01
Somatic mutations are transmitted during mitosis in developing somatic tissue. Somatic cells bearing the mutations can develop into reproductive (germ) cells and the somatic mutations are then passed on to the next generation of plants. Somatic mutations are a source of variation essential to evolve new defense strategies and adapt to the environment. Stem rust disease in Scots pine has a negative effect on wood quality, and thus adversely affects the economy. It is caused by the 2 most destructive fungal species in Scandinavia: Peridermium pini and Cronartium flaccidum. We studied nuclear genome stability in Scots pine under biotic stress (fungus-infected, 22 trees) compared to a control population (plantation, 20 trees). Stability was assessed as accumulation of new somatic mutations in 10 microsatellite loci selected for genotyping. Microsatellites are widely used as molecular markers in population genetics studies of plants, and are particularly used for detection of somatic mutations as their rate of mutation is of a much higher magnitude when compared with other DNA markers. We report double the rate of somatic mutation per locus in the fungus-infected trees (4.8×10(-3) mutations per locus), as compared to the controls (2.0×10(-3) mutations per locus) when individual samples were analyzed at 10 different microsatellite markers. Pearson's chi-squared test indicated a significant effect of the fungal infection which increased the number of mutations in the fungus-infected trees (χ(2) = 12.9883, df = 1, P = 0.0003134). © The American Genetic Association 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.