Non-target-site resistance (NTSR) to herbicides that disrupts agricultural weed control is a worldwide concern for food security. NTSR is considered a polygenic adaptive trait driven by differential ...gene regulation in resistant plants. Little is known about its genetic determinism, which precludes NTSR diagnosis and evolutionary studies. We used Illumina RNA-sequencing to investigate transcriptomic differences between plants from the global major weed rye-grass sensitive or resistant to the acetolactate-synthase (ALS) inhibiting herbicide pyroxsulam. Plants were collected before and along a time-course after herbicide application. De novo transcriptome assembly yielded a resource (LOLbase) including 92,381 contigs representing potentially active transcripts that were assigned putative annotations. Early effects of ALS inhibition consistent with the literature were observed in resistant and sensitive plants, proving LOLbase data were relevant to study herbicide response. Comparison of resistant and sensitive plants identified 30 candidate NTSR contigs. Further validation using 212 plants resistant or sensitive to pyroxsulam and/or to the ALS inhibitors iodosulfuron + mesosulfuron confirmed four contigs (two cytochromes P450, one glycosyl-transferase and one glutathione-
S
-transferase) were NTSR markers which combined expression levels could reliably identify resistant plants. This work confirmed that NTSR is driven by differential gene expression and involves different mechanisms. It provided tools and foundation for subsequent NTSR investigations.
Variation in the expression of numerous genes is at the basis of plant response to environmental stresses. Non-target-site-based resistance to herbicides (NTSR), the major threat to grass weed ...chemical control, is governed by a subset of the genes involved in herbicide stress response. Quantitative PCR assays allowing reliable comparison of gene expression are thus key to identify genes governing NTSR. This work aimed at identifying a set of reference genes with a stable expression to be used as an internal standard for the normalisation of quantitative PCR data in studies investigating NTSR to herbicides inhibiting acetolactate synthase (ALS) in the major grass weed Lolium sp. Gene expression stability was assessed in plants resistant or sensitive to two ALS inhibitors, subjected or not to herbicide stress. Using three complementary approaches implemented in the programs BestKeeper, NormFinder and geNorm, cap-binding protein, glyceraldehyde-3-phosphate-dehydrogenase and ubiquitin were identified as the most suitable reference genes. This reference gene set can probably be used to study herbicide response in other weed species. It was used to compare the expression of the genes encoding two herbicide target enzymes (ALS and acetyl-coenzyme A carboxylase) and five cytochromes P450 (CYP) with potential herbicide-degrading activity between plants resistant or sensitive to ALS inhibitors. Overall, herbicide application enhanced CYP gene expression. Constitutive up-regulation of all CYP genes observed in resistant plants compared to sensitive plants suggested enhanced secondary metabolism in the resistant plants. Comprehensive transcriptome studies associated to gene expression analyses using the reference gene set validated here are required to unravel NTSR genetic determinants.
This article discusses the nature and structure of scientific collaboration as well as the association between academic collaboration networks and scientific productivity. Based on empirical data ...gathered from the CVs of 73 researchers affiliated with an academic research network in Canada, this study used social network analysis (SNA) to examine the association between researchers' structural position in the network and their scientific performance. With reference to Granovetter's and Burt's theories on weak ties and structural holes, we argue it is the bridging position a researcher holds in a scientific network that matters most to improve scientific performance. The results of correlation scores between network centrality and two different indicators of scientific performance indicate there is a robust association between researchers' structural position in collaboration networks and their scientific performance. We believe this finding, and the method we have developed, could have implications for the way research networks are managed and researchers are supported.
There is a gap between clinical practice guidelines for social anxiety disorder and clinical practice that needs to be addressed to ensure the delivery of evidence-based treatments. The objectives of ...this study were: 1) to describe mental health service utilization in a cohort of primary care patients with social anxiety disorder; 2) to examine treatment adequacy for pharmacotherapy and psychotherapy according to indicators based on clinical practice guidelines; and 3) to explore correlates of treatment adequacy.
The "Dialogue" project (Quebec, Canada) is a large study conducted in 67 primary care clinics. After a mental health screening in primary care (n = 14 833), participants with anxiety or depressive symptoms took part in a telephone/web structured interview on mental health symptoms and service utilization (n = 1956). This study included 289 participants meeting DSM-IV criteria for social anxiety disorder.
Overall, 86.2% of participants reported consulting for mental health reasons over the past 12 months. Only 23.6% of our sample reported the detection of social anxiety disorder by a healthcare professional in the past 12 months. Approximately 2 in 5 respondents with social anxiety disorder reported receiving pharmacotherapy or psychotherapy meeting our treatment adequacy indicators. Antidepressant medication was the most common treatment. Logistic regression models showed that the detection of major depression (OR = 4.651; 95% CI: 2.559-8.453) or other anxiety disorder(s) (OR = 2.957; 95% CI: 1.555-5.625) were associated with receiving any adequate treatment, but the detection of social anxiety disorder itself was not (OR = 1.420; 95% CI: 0.696-2.899).
Low rates of detection and treatment adequacy based on our indicators demonstrate that efforts must be made to ensure the quality of care for individuals with social anxiety disorder in primary care.
ObjectiveThis study aims to evaluate the impact of a primary care nurse practitioner (NP)-led clinic model piloted in British Columbia (Canada) on patients’ health and care experience.DesignThe study ...relies on a quasi-experimental longitudinal design based on a pre-and-post survey of patients receiving care in NP-led clinics. The prerostering survey (T0) was focused on patients’ health status and care experiences preceding being rostered to the NP clinic. One year later, patients were asked to complete a similar survey (T1) focused on the care experiences with the NP clinic.SettingTo solve recurring problems related to poor primary care accessibility, British Columbia opened four pilot NP-led clinics in 2020. Each clinic has the equivalent of approximately six full-time NPs, four other clinicians plus support staff. Clinics are located in four cities ranging from urban to suburban.ParticipantsRecruitment was conducted by the clinic’s clerical staff or by their care provider. A total of 437 usable T0 surveys and 254 matched and usable T1 surveys were collected.Primary outcome measuresThe survey instrument was focused on five core dimensions of patients’ primary care experience (accessibility, continuity, comprehensiveness, responsiveness and outcomes of care) as well as on the SF-12 Short-form Health Survey.ResultsScores for all dimensions of patients’ primary care experience increased significantly: accessibility (T0=5.9, T1=7.9, p<0.001), continuity (T0=5.5, T1=8.8, p<0.001), comprehensiveness (T0=5.6, T1=8.4, p<0.001), responsiveness (T0=7.2, T1=9.5, p<0.001), outcomes of care (T0=5.0, T1=8.3, p<0.001). SF-12 Physical health T-scores also rose significantly (T0=44.8, T1=47.6, p<0.001) but no changes we found in the mental health T scores (T0=45.8, T1=46.3 p=0.709).ConclusionsOur results suggest that the NP-led primary care model studied here likely constitutes an effective approach to improve primary care accessibility and quality.
Abstract Background In 2021, the National Institute of Public Health (INSPQ) (Quebec, Canada), published an update of the palliative and end-of-life care (PEoLC) indicators. Using these updated ...indicators, this qualitative study aimed to explore the point of view of PEoLC experts on how to improve access and quality of care as well as policies surrounding end-of-life care. Methods Semi-directed interviews were conducted with palliative care and policy experts, who were asked to share their interpretations on the updated indicators and their recommendations to improve PEoLC. A thematic analysis method was used. Results The results highlight two categories of interpretations and recommendations pertaining to: (1) data and indicators and (2) clinical and organizational practice. Participants highlight the lack of reliability and quality of the data and indicators used by political and clinical stakeholders in evaluating PEoLC. To improve data and indicators, they recommend: improving the rigour and quality of collected data, assessing death percentages in all healthcare settings, promoting research on quality of care, comparing data to EOL care directives, assessing use of services in EOL, and creating an observatory on PEoLC. Participants also identified barriers and disparities in accessing PEoLC as well as inconsistency in quality of care. To improve PEoLC, they recommend: early identification of palliative care patients, improving training for all healthcare professionals, optimizing professional practice, integrating interdisciplinary teams, and developing awareness on access disparities. Conclusions Results show that PEoLC is an important aspect of public health. Recommendations issued are relevant to improve PEoLC in and outside Quebec.
Herbicides are currently pivotal to control weeds and sustain food security. Herbicides must efficiently kill weeds while being as harmless as possible for crops, even crops taxonomically close to ...weeds. To increase their selectivity toward crops, some herbicides are sprayed in association with safeners that are bioactive compounds exacerbating herbicide-degrading pathways reputedly specifically in crops. However, exacerbated herbicide metabolism is also a key mechanism underlying evolved non-target-site-based resistance to herbicides (NTSR) in weeds. This raised the issue of a possible role of safeners on NTSR evolution in weeds. We investigated a possible effect of the respective field rates of the two broadly used safeners cloquintocet-mexyl and mefenpyr-diethyl on the sensitivity of the troublesome global weed
sp. (rye-grass) to the major herbicides inhibiting acetolactate-synthase (ALS) pyroxsulam and iodosulfuron + mesosulfuron, respectively. Three
sp. populations were studied in three series of experiments. The first experiment series compared the frequencies of plants surviving application of each herbicide alone or in association with its safener. Safener co-application caused a net increase ranging from 5.0 to 46.5% in the frequency of plants surviving the field rate of their associated herbicide. In a second series of experiments, safener effect was assessed on individual plant sensitivity using vegetative propagation. A reduction in sensitivity to pyroxsulam and to iodosulfuron + mesosulfuron was observed for 44.4 and 11.1% of the plants in co-treatment with cloquintocet-mexyl and mefenpyr-diethyl, respectively. A third series of experiments investigated safener effect on the expression level of 19
sp. NTSR marker genes. Safeners showed an enhancing effect on the expression level of 10 genes. Overall, we demonstrated that cloquintocet-mexyl and mefenpyr-diethyl both reduced the sensitivity of
sp. to their associated ALS-inhibiting herbicide and most likely exacerbated herbicide-degrading secondary metabolism pathways. This suggests that genetic variation for safener response is present in
sp. Thus, a possible, uninvestigated way to NTSR evolution could be selection for increased responsiveness to safener action. Delivering safeners exclusively to the crop could mitigate the risk for NTSR evolution in weeds.
Resistance to herbicides occurs in weeds as the result of evolutionary adaptation (Jasieniuk et al. 1996). Basically, two types of mechanisms are involved in resistance (Beckie and Tardif 2012; Délye ...2013). Target-site resistance (TSR) is caused by changes in the tridimensional structure of the herbicide target protein that decrease herbicide binding, or by increased activity (e.g., due to increased expression or increased intrinsic activity) of the target protein. Nontarget-site resistance (NTSR) is endowed by any mechanism not belonging to TSR, e.g., reduction in herbicide uptake or translocation in the plant, or enhanced herbicide detoxification (reviewed in Délye 2013; Yuan et al. 2007).
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