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991.
Lauren L Hulsman Hanna James O Sanders David G Riley Colette A Abbey Clare A Gill 《遗传、选种与进化》2014,46(1):4
Background
In cattle, base color is assumed to depend on the enzymatic activity specified by the MC1R locus, i.e. the extension locus, with alleles coding for black (E D ), red (e), and wild-type (E + ). In most mammals, these alleles are presumed to follow the dominance model of E D > E + > e, although exceptions are found. In Bos indicus x Bos taurus F2 cattle, some E D E + heterozygotes are discordant with the dominance series for MC1R and display various degrees of red pigmentation on an otherwise predicted black background. The objective of this study was to identify loci that modify black coat color in these individuals.Results
Reddening was classified with a subjective scoring system. Interval analyses identified chromosome-wide suggestive (P < 0.05) and significant (P < 0.01) QTL on bovine chromosomes (BTA) 4 and 5, although these were not confirmed using single-marker association or Bayesian methods. Evidence of a major locus (F = 114.61) that affects reddening was detected between 60 and 73 Mb on BTA 6 (Btau4.0 build), and at 72 Mb by single-marker association and Bayesian methods. The posterior mean of the genetic variance for this region accounted for 43.75% of the genetic variation in reddening. This region coincided with a cluster of tyrosine kinase receptor genes (PDGFRA, KIT and KDR). Fitting SNP haplotypes for a 1 Mb interval that contained all three genes and centered on KIT accounted for the majority of the variation attributed to this major locus, which suggests that one of these genes or associated regulatory elements, is responsible for the majority of variation in degree of reddening.Conclusions
Recombinants in a 5 Mb region surrounding the cluster of tyrosine kinase receptor genes implicated PDGFRA as the strongest positional candidate gene. A higher density marker panel and functional analyses will be required to validate the role of PDGFRA or other regulatory variants and their interaction with MC1R for the modification of black coat color in Bos indicus influenced cattle. 相似文献992.
Lauren L. Hulsman Hanna Dorian J. Garrick Clare A. Gill Andy D. Herring James O. Sanders David G. Riley 《Genetics and molecular biology》2014,37(4):631-637
The objectives of this study were to 1) compare four models for breeding value prediction using genomic or pedigree information and 2) evaluate the impact of fixed effects that account for family structure. Comparisons were made in a Nellore-Angus population comprising F2, F3 and half-siblings to embryo transfer F2 calves with records for overall temperament at weaning (TEMP; n = 769) and Warner-Bratzler shear force (WBSF; n = 387). After quality control, there were 34,913 whole genome SNP markers remaining. Bayesian methods employed were BayesB ( = 0.995 or 0.997 for WBSF or TEMP, respectively) and BayesC (π = 0 and ), where is the ideal proportion of markers not included. Direct genomic values (DGV) from single trait Bayesian analyses were compared to conventional pedigree-based animal model breeding values. Numerically, BayesC procedures (using ) had the highest accuracy of all models for WBSF and TEMP (gĝ = 0.843 and 0.923, respectively), but BayesB had the least bias (regression of performance on prediction closest to 1, y,x = 2.886 and 1.755, respectively). Accounting for family structure decreased accuracy and increased bias in prediction of DGV indicating a detrimental impact when used in these prediction methods that simultaneously fit many markers. 相似文献
993.
Mary Leamy Eleanor Clarke Clair Le Boutillier Victoria Bird Monika Janosik Kai Sabas Genevieve Riley Julie Williams Mike Slade 《PloS one》2014,9(5)
Objective
To investigate staff and trainer perspectives on the barriers and facilitators to implementing a complex intervention to help staff support the recovery of service users with a primary diagnosis of psychosis in community mental health teams.Design
Process evaluation nested within a cluster randomised controlled trial (RCT).Participants
28 interviews with mental health care staff, 3 interviews with trainers, 4 focus groups with intervention teams and 28 written trainer reports.Setting
14 community-based mental health teams in two UK sites (one urban, one semi-rural) who received the intervention.Results
The factors influencing the implementation of the intervention can be organised under two over-arching themes: Organisational readiness for change and Training effectiveness. Organisational readiness for change comprised three sub-themes: NHS Trust readiness; Team readiness; and Practitioner readiness. Training effectiveness comprised three sub-themes: Engagement strategies; Delivery style and Modelling recovery principles.Conclusions
Three findings can inform future implementation and evaluation of complex interventions. First, the underlying intervention model predicted that three areas would be important for changing practice: staff skill development; intention to implement; and actual implementation behaviour. This study highlighted the importance of targeting the transition from practitioners'' intent to implement to actual implementation behaviour, using experiential learning and target setting. Second, practitioners make inferences about organisational commitment by observing the allocation of resources, Knowledge Performance Indicators and service evaluation outcome measures. These need to be aligned with recovery values, principles and practice. Finally, we recommend the use of organisational readiness tools as an inclusion criteria for selecting both organisations and teams in cluster RCTs. We believe this would maximise the likelihood of adequate implementation and hence reduce waste in research expenditure.Trial Registration
Controlled-Trials.com ISRCTN02507940 相似文献994.
Maristela G. Cunha Eliane S. Silva Nuno Sepúlveda Sheyla P. T. Costa Tiago C. Saboia Jo?o F. Guerreiro Marinete M. Póvoa Patrick H. Corran Eleanor Riley Chris J. Drakeley 《PloS one》2014,9(11)
Background
Measurement of malaria endemicity is typically based on vector or parasite measures. A complementary approach is the detection of parasite specific IgG antibodies. We determined the antibody levels and seroconversion rates to both P. vivax and P. falciparum merozoite antigens in individuals living in areas of varying P. vivax endemicity in Pará state, Brazilian Amazon region.Methodology/Principal Findings
The prevalence of antibodies to recombinant antigens from P. vivax and P. falciparum was determined in 1,330 individuals. Cross sectional surveys were conducted in the north of Brazil in Anajás, Belém, Goianésia do Pará, Jacareacanga, Itaituba, Trairão, all in the Pará state, and Sucuriju, a free-malaria site in the neighboring state Amapá. Seroprevalence to any P. vivax antigens (MSP1 or AMA-1) was 52.5%, whereas 24.7% of the individuals were seropositive to any P. falciparum antigens (MSP1 or AMA-1). For P. vivax antigens, the seroconversion rates (SCR) ranged from 0.005 (Sucuriju) to 0.201 (Goianésia do Pará), and are strongly correlated to the corresponding Annual Parasite Index (API). We detected two sites with distinct characteristics: Goianésia do Pará where seroprevalence curve does not change with age, and Sucuriju where seroprevalence curve is better described by a model with two SCRs compatible with a decrease in force of infection occurred 14 years ago (from 0.069 to 0.005). For P. falciparum antigens, current SCR estimates varied from 0.002 (Belém) to 0.018 (Goianésia do Pará). We also detected a putative decrease in disease transmission occurred ∼29 years ago in Anajás, Goianésia do Pará, Itaituba, Jacareacanga, and Trairão.Conclusions
We observed heterogeneity of serological indices across study sites with different endemicity levels and temporal changes in the force of infection in some of the sites. Our study provides further evidence that serology can be used to measure and monitor transmission of both major species of malaria parasite. 相似文献995.
Lucius K. Caldwell Andrew L. Pierce Larry G. Riley Christine A. Duncan James J. Nagler 《PloS one》2014,9(1)
The metabolic peptide hormone nesfatin-1 has been linked to the reproductive axis in fishes. The purpose of this study was to determine how energy availability after spawning affects plasma levels of nesfatin-1, the metabolic peptide hormone ghrelin, and sex steroid hormones in rematuring female rainbow trout (Oncorhynchus mykiss). To limit reproductive maturation, a group of female trout was food-restricted after spawning and compared with a control group that was fed a standard broodstock ration. The experiment was conducted twice, once using two-year-old trout (second-time spawners) and once using three-year-old trout (third-time spawners). During monthly sampling, blood was collected from all fish, and a subset of fish from each treatment was sacrificed for pituitaries. Pituitary follicle-stimulating hormone-beta (fsh-β) mRNA expression was analyzed with q-RT-PCR; plasma hormone levels were quantified by radioimmunoassay (17β-estradiol and ghrelin) and enzyme-linked immunosorbent assay (11-keto-testosterone and nesfatin-1). Although plasma nesfatin-1 levels increased significantly in the months immediately after spawning within both feeding treatments, plasma nesfatin-1 did not differ significantly between the two treatments at any point. Similarly, plasma ghrelin levels did not differ significantly between the two treatments at any point. Food restriction arrested ovarian development by 15–20 weeks after spawning, shown by significantly lower plasma E2 levels among restricted-ration fish. Pituitary fsh-β mRNA levels were higher among control-ration fish than restricted-ration fish starting at 20 weeks, but did not differ significantly between treatment groups until 30 weeks after spawning. Within both treatment groups, plasma 11-KT was elevated immediately after spawning and rapidly decreased to and persisted at low levels; starting between 20 and 25 weeks after spawning, plasma 11-KT was higher among control-ration fish than restricted-ration fish. The results from these experiments do not provide support for plasma nesfatin-1 as a signal for the initiation of reproductive development in rematuring female rainbow trout. 相似文献
996.
997.
Jessica E. Marsh Rasmus B. Lauridsen William D. Riley Olivia M. Simmons Céline Artero Luke J. Scott William R. C. Beaumont William A. Beaumont John Davy-Bowker Thomas Lecointre Dylan E. Roberts Stephen D. Gregory 《Journal of fish biology》2021,99(3):1125-1129
Previous work suggests that juvenile salmon recruitment in rain-fed rivers is negatively influenced by warm and wet winters and cool springs. We tested whether this is generally applicable to a southern England chalk stream characterized by comparatively stable discharges and temperatures. We found that warm spawning and cool emergence temperatures negatively influenced juvenile recruitment between 2015 and 2020. Together these findings suggest an ability to predict juvenile productivity from water temperature records around spawning and fry emergence, thereby allowing time for management interventions in years of unfavourable temperatures. 相似文献
998.
999.
Riley Erin P. Shaffer Christopher A. Trinidad Joshua S. Morrow Kristen S. Sagnotti Cristina Carosi Monica Ngakan Putu Oka 《Primates; journal of primatology》2021,62(3):477-489
Primates - A growing body of research focuses on how anthropogenic factors affect the behavior and ecology of primates and their ecosystems. Infrastructural development, such as roads, is an... 相似文献
1000.