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Objective Internet-based interventions may positively impact maternal symptoms of postnatal depression and anxiety. This study assessed the feasibility, acceptability, perceived usefulness, and preliminary effectiveness of an m-Health version of "What Were We Thinking?" (m-WWWT). Methods A mixed-methods with a 2-arm randomized parallel design was used. From a total of 477 women, 157 met the inclusion criteria. 128 first-time mothers of full-term infants, aged 4–10 weeks, who received health care at primary public health centers in Chile, were randomly assigned to the experimental (EG, n  = 65) or control (CG, n  = 63) groups; data of 104 of them (53 and 51, respectively) was analyzed. We used percentages and rates to measure feasibility outcomes and mixed analysis of variance (ANOVA) and latent class analyses (LCA) to assess preliminary effectiveness. Participants completed questionnaires on mental health, social support, and maternal self-efficacy upon recruitment and 3 months after completing the intervention. For the qualitative component, 12 women from the EG were interviewed. Results Quantitative results show good feasibility outcomes, such as high recruitment (82%), low attrition (EG = 12% and CG = 17%), and high follow-up (EG = 97% and CG = 91%) rates. Qualitative results indicate high acceptability and perceived usefulness of m-WWWT. Mixed ANOVA did not show significant differences between the groups (all p >.05). However, multinomial regression analysis in LCA showed that women with low baseline symptoms of depression and anxiety benefit from the intervention (B  = 0.43, 95% confidence interval 1.09–2.16). Conclusion m-WWWT is feasible to be implemented in Chile; future studies are needed to assess the intervention's effectiveness. [ABSTRACT FROM AUTHOR]

BackgroundGenome-wide association (GWA) is gaining popularity as a means to study the architecture of complex quantitative traits, partially due to the improvement of high-throughput low-cost genotyping and phenotyping technologies. Glucosinolate (GSL) secondary metabolites within Arabidopsis spp. can serve as a model system to understand the genomic architecture of adaptive quantitative traits. GSL are key anti-herbivory defenses that impart adaptive advantages within field trials. While little is known about how variation in the external or internal environment of an organism may influence the efficiency of GWA, GSL variation is known to be highly dependent upon the external stresses and developmental processes of the plant lending it to be an excellent model for studying conditional GWA.Methodology/principal findingsTo understand how development and environment can influence GWA, we conducted a study using 96 Arabidopsis thaliana accessions, >40 GSL phenotypes across three conditions (one developmental comparison and one environmental comparison) and ∼230,000 SNPs. Developmental stage had dramatic effects on the outcome of GWA, with each stage identifying different loci associated with GSL traits. Further, while the molecular bases of numerous quantitative trait loci (QTL) controlling GSL traits have been identified, there is currently no estimate of how many additional genes may control natural variation in these traits. We developed a novel co-expression network approach to prioritize the thousands of GWA candidates and successfully validated a large number of these genes as influencing GSL accumulation within A. thaliana using single gene isogenic lines.Conclusions/significanceTogether, these results suggest that complex traits imparting environmentally contingent adaptive advantages are likely influenced by up to thousands of loci that are sensitive to fluctuations in the environment or developmental state of the organism. Additionally, while GWA is highly conditional upon genetics, the use of additional genomic information can rapidly identify causal loci en masse.

Discovering links between the genotype of an organism and its metabolite levels can increase our understanding of metabolism, its controls, and the indirect effects of metabolism on other quantitative traits. Recent technological advances in both DNA sequencing and metabolite profiling allow the use of broad-spectrum, untargeted metabolite profiling to generate phenotypic data for genome-wide association studies that investigate quantitative genetic control of metabolism within species. We conducted a genome-wide association study of natural variation in plant metabolism using the results of untargeted metabolite analyses performed on a collection of wild Arabidopsis thaliana accessions. Testing 327 metabolites against >200,000 single nucleotide polymorphisms identified numerous genotype-metabolite associations distributed non-randomly within the genome. These clusters of genotype-metabolite associations (hotspots) included regions of the A. thaliana genome previously identified as subject to recent strong positive selection (selective sweeps) and regions showing trans-linkage to these putative sweeps, suggesting that these selective forces have impacted genome-wide control of A. thaliana metabolism. Comparing the metabolic variation detected within this collection of wild accessions to a laboratory-derived population of recombinant inbred lines (derived from two of the accessions used in this study) showed that the higher level of genetic variation present within the wild accessions did not correspond to higher variance in metabolic phenotypes, suggesting that evolutionary constraints limit metabolic variation. While a major goal of genome-wide association studies is to develop catalogues of intraspecific variation, the results of multiple independent experiments performed for this study showed that the genotype-metabolite associations identified are sensitive to environmental fluctuations. Thus, studies of intraspecific variation conducted via genome-wide association will require analyses of genotype by environment interaction. Interestingly, the network structure of metabolite linkages was also sensitive to environmental differences, suggesting that key aspects of network architecture are malleable.

Despite the described central role of jasmonate signaling in plant defense against necrotrophic pathogens, the existence of intraspecific variation in pathogen capacity to activate or evade plant jasmonate-mediated defenses is rarely considered. Experimental infection of jasmonate-deficient and jasmonate-insensitive Arabidopsis thaliana with diverse isolates of the necrotrophic fungal pathogen Botrytis cinerea revealed pathogen variation for virulence inhibition by jasmonate-mediated plant defenses and induction of plant defense metabolites. Comparison of the transcriptional effects of infection by two distinct B. cinerea isolates showed only minor differences in transcriptional responses of wild-type plants, but notable isolate-specific transcript differences in jasmonate-insensitive plants. These transcriptional differences suggest B. cinerea activation of plant defenses that require plant jasmonate signaling for activity in response to only one of the two B. cinerea isolates tested. Thus, similar infection phenotypes observed in wild-type plants result from different signaling interactions with the plant that are likely integrated by jasmonate signaling.

Organisms are continuously exposed to a myriad of environmental stresses. Central to an organism's survival is the ability to mount a robust transcriptional response to the imposed stress. An emerging mechanism of transcriptional control involves dynamic changes in chromatin structure. Alterations in chromatin structure are brought about by a number of different mechanisms, including chromatin modifications, which covalently modify histone proteins; incorporation of histone variants; and chromatin remodeling, which utilizes ATP hydrolysis to alter histone-DNA contacts. While considerable insight into the mechanisms of chromatin remodeling has been gained, the biological role of chromatin remodeling complexes beyond their function as regulators of cellular differentiation and development has remained poorly understood. Here, we provide genetic, biochemical, and biological evidence for the critical role of chromatin remodeling in mediating plant defense against specific biotic stresses. We found that the Arabidopsis SWI/SNF class chromatin remodeling ATPase SPLAYED (SYD) is required for the expression of selected genes downstream of the jasmonate (JA) and ethylene (ET) signaling pathways. SYD is also directly recruited to the promoters of several of these genes. Furthermore, we show that SYD is required for resistance against the necrotrophic pathogen Botrytis cinerea but not the biotrophic pathogen Pseudomonas syringae. These findings demonstrate not only that chromatin remodeling is required for selective pathogen resistance, but also that chromatin remodelers such as SYD can regulate specific pathways within biotic stress signaling networks.

BackgroundMany inducible plant-defense responses are activated by jasmonates (JAs), C(6)-aldehydes, and their corresponding derivatives, produced by the two main competing branches of the oxylipin pathway, the allene oxide synthase (AOS) and hydroperoxide lyase (HPL) branches, respectively. In addition to competition for substrates, these branch-pathway-derived metabolites have substantial overlap in regulation of gene expression. Past experiments to define the role of C(6)-aldehydes in plant defense responses were biased towards the exogenous application of the synthetic metabolites or the use of genetic manipulation of HPL expression levels in plant genotypes with intact ability to produce the competing AOS-derived metabolites. To uncouple the roles of the C(6)-aldehydes and jasmonates in mediating direct and indirect plant-defense responses, we generated Arabidopsis genotypes lacking either one or both of these metabolites. These genotypes were subsequently challenged with a phloem-feeding insect (aphids: Myzus persicae), an insect herbivore (leafminers: Liriomyza trifolii), and two different necrotrophic fungal pathogens (Botrytis cinerea and Alternaria brassicicola). We also characterized the volatiles emitted by these plants upon aphid infestation or mechanical wounding and identified hexenyl acetate as the predominant compound in these volatile blends. Subsequently, we examined the signaling role of this compound in attracting the parasitoid wasp (Aphidius colemani), a natural enemy of aphids.Principal findingsThis study conclusively establishes that jasmonates and C(6)-aldehydes play distinct roles in plant defense responses. The jasmonates are indispensable metabolites in mediating the activation of direct plant-defense responses, whereas the C(6)-aldehyes are not. On the other hand, hexenyl acetate, an acetylated C(6)-aldehyde, is the predominant wound-inducible volatile signal that mediates indirect defense responses by directing tritrophic (plant-herbivore-natural enemy) interactions.SignificanceThe data suggest that jasmonates and hexenyl acetate play distinct roles in mediating direct and indirect plant-defense responses. The potential advantage of this "division of labor" is to ensure the most effective defense strategy that minimizes incurred damages at a reduced metabolic cost.

Standardization of pest monitoring practices and materials to maximize sensitivity to pest populations in the field is a foundation of effective integrated pest management (IPM). In response to changes in the availability of commercial bait material for navel orangeworm (NOW) egg traps, we evaluated potential alternative bait materials for use in monitoring this key pest of almonds, pistachios, walnuts and figs. Navel orangeworm egg traps baited with uninfested nutmeats were as effective as almond meal plus 10% crude almond oil, whereas traps baited with freeze-killed, navel orangeworm–infested nutmeats were less effective. The use of nut mummies (culled during winter orchard sanitation) as trap bait may not produce consistent results since the level of navel orangeworm infestation of these nuts is typically unknown. Three seasons of field tests showed that egg traps baited with almond meal plus 3% or 10% crude almond oil received similar numbers of navel orangeworm eggs, and these traps were equally effective for at least 10 weeks.

Phenotypic variation between individuals of a species is often under quantitative genetic control. Genomic analysis of gene expression polymorphisms between individuals is rapidly gaining popularity as a way to query the underlying mechanistic causes of variation between individuals. However, there is little direct evidence of a linkage between global gene expression polymorphisms and phenotypic consequences. In this report, we have mapped quantitative trait loci (QTLs)-controlling glucosinolate content in a population of 403 Arabidopsis Bay x Sha recombinant inbred lines, 211 of which were previously used to identify expression QTLs controlling the transcript levels of biosynthetic genes. In a comparative study, we have directly tested two plant biosynthetic pathways for association between polymorphisms controlling biosynthetic gene transcripts and the resulting metabolites within the Arabidopsis Bay x Sha recombinant inbred line population. In this analysis, all loci controlling expression variation also affected the accumulation of the resulting metabolites. In addition, epistasis was detected more frequently for metabolic traits compared to transcript traits, even when both traits showed similar distributions. An analysis of candidate genes for QTL-controlling networks of transcripts and metabolites suggested that the controlling factors are a mix of enzymes and regulatory factors. This analysis showed that regulatory connections can feedback from metabolism to transcripts. Surprisingly, the most likely major regulator of both transcript level for nearly the entire pathway and aliphatic glucosinolate accumulation is variation in the last enzyme in the biosynthetic pathway, AOP2. This suggests that natural variation in transcripts may significantly impact phenotypic variation, but that natural variation in metabolites or their enzymatic loci can feed back to affect the transcripts.

Introduction Despite the considerable and increasing proportion of women of reproductive age with a chronic non-communicable disease (NCD) and the potential adverse implications of many NCDs for childbearing, little is known about the fertility management experiences of women with an NCD, including their contraceptive use, pregnancy experiences and outcomes, and reproductive health care utilisation. The aim of this study was to investigate the fertility management experiences of women with an NCD and draw comparisons with women without an NCD. Method A sample of 18-50 year-old women (n = 1543) was randomly recruited from the Australian electoral roll in 2013. Of these women, 172 women reported a physical, chronic non-communicable disease: diabetes, arthritis, asthma, hypertension, heart disease, thyroid disorders, and cystic fibrosis. Respondents completed an anonymous, self-administered questionnaire. Factors associated with fertility management were identified in multivariable analyses. Results Women who reported having an NCD were significantly more likely than women who did not report an NCD to have ever been pregnant (75.9 vs. 67.5%, p = 0.034), have had an unintended pregnancy (33.47 vs. 25.5%, p = 0.026), and have had an abortion (20.3 vs. 14.2%, p = 0.044); they were less likely to consult a healthcare provider about fertility management (45.0 vs. 54.4%, p = 0.024). Similar proportions were using contraception (48.8 vs. 54.5%, p = 0.138). Conclusion The findings have implications for healthcare providers and women with an NCD and highlight the importance of addressing possible assumptions about the inability of women with an NCD to become pregnant, and ensuring women receive information about suitable methods of contraception and pre-pregnancy care., Author(s): Sara Holton [sup.1] , Aberaami Thananjeyan [sup.1] , Heather Rowe [sup.1] , Maggie Kirkman [sup.1] , Lynne Jordan [sup.2] , Kathleen McNamee [sup.2] , Christine Bayly [sup.3] , John [...]

While infant behaviour is influenced by maternal care, infant crying and dysregulated sleep can reciprocally affect maternal mood. The temperament and behaviour of two 4-12-months-old infant cohorts admitted with their mothers to a residential parenting program were examined using behaviour charts and the Short Infant Temperament Questionnaire (SITQ). One group was re-assessed one and six months later. Infant temperament was significantly more difficult than population norms and most had dysregulated sleep. One month after treatment, total infant crying and fussing, frequency of night-time waking, and sleep and feeding dysregulation were significantly (p less than 0.001) reduced, with change sustained at six months. Easy-Difficult scores (SITQ) were stable and significantly worse than population norms. The contribution of a "difficult" infant temperament to maternal mood disorder warrants further investigation. (Contains 5 tables.)