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Access status: Open Access ,
Evaluation of Physical Strategies for Kochia (Bassia scoparia) Patch Management and Soil Remediation
(Canadian Science Publishing, 2025-12-16) Sharpe, Shaun M.; Rosvold, Kyle; Chester, Leonard; St. Jacques, Shaelyn; Town, Jennifer; Gill, Krista; Chan, Wan Anastasia; Gowera, Grace Tariro; Asgedom, Haben; Leeson, Julia Y.
Kochia is a problematic tumbleweed which infests Prairie annual cropping systems. Due to herbicide resistance adaptation by kochia, additional nonchemical management methods are required. The study objective was to evaluate the efficacy of physical management strategies on kochia stand densities and soil characteristics including microbiome, chemistry, and allelochemical buildup within established kochia patches on the Prairie. Unmanaged infestations reached a maximum stand density of 10,000 plants m-2 in 2022. Black plastic mulch completely suppressed kochia while mowing reduced densities to 2 to 7% of the untreated control in 2021 and 2023, respectively. The chaff treatment was effective over the three-year term, with one application reducing stand densities to 5 to 14% of the untreated control in 2021, 5 to 22% in 2022, and 22 to 56% in 2023. Mowing may be suitable where total crop failure may occur to prevent kochia reproduction. Field chaff was a promising option to limit stand densities but additional study is required for compatibility within annual cropping systems. Soil allelochemicals were rarely detected above thresholds, a promising result for soil remediation post-infestation. Neither the diversity, nor the composition of the soil bacterial and fungal communities were impacted by mechanical treatments, however kochia patches were associated with specific microorganisms compared to the cropped soil, including Thanatephorus and Neocamaosporium . The soil EC in the patch declined each year and soil electrical conductivity, NO3-N, and SO4-S were the most important characteristics to explain kochia density using machine learning.
Access status: Open Access ,
Current Clinical Application of Incretin Therapy for Obesity Management
(Canadian Science Publishing, 2025-09-17) Skinner, Karlie; Clements, Jennifer Nicole
Incretin therapy, utilizing glucagon-like peptide-1 (GLP-1) receptor agonists and dual receptor agonists, is a cornerstone of obesity management due to effects on appetite suppression, weight loss, and metabolic improvement. Liraglutide, semaglutide, and tirzepatide promote weight reduction by modulating incretin hormone pathways, leading to decreased caloric intake. Recent studies with semaglutide and tirzepatide have demonstrated substantial weight loss outcomes beyond glucose-lowering benefits, shifting the paradigm of obesity treatment toward pharmacological interventions. While effective in weight loss, challenges remain regarding long-term efficacy, tolerability, and accessibility. Future directions include optimizing combination therapies and exploring novel incretin-based molecules with dual or triple receptor activity. This review focuses on the clinical application of incretin therapy in obesity, emphasizing practical considerations and highlighting therapeutic benefits for obesity to improve outcomes and public health.
Access status: Open Access ,
Quantitative trait loci underlying resistance to the soybean cyst nematode in PI 507354
(Canadian Science Publishing, 2025-11-18) Boucher St-Amour, Vincent Thomas; Gélinas Bélanger, Jérôme; Mimee, Benjamin; Fortier, Éric; Belzile, François; O'Donoughue, Louise
Due to the current prevalence and shift in virulence of Heterodera glycines, the soybean cyst nematode (SCN), there is a pressing need to find sustainable alternatives or complements to the commonly found Rhg1 and Rhg4 resistance loci. The objective of this study was to find novel QTL to expand the toolbox for SCN resistance. To do so, a population of recombinant inbred lines named QS13073 was generated from a biparental cross between a SCN susceptible cultivar (S12-A5) and a SCN resistant accession (PI 507354, also named Tokei 421). Using four mapping algorithms (SMA, ICIM, GCIM and R/qtl2), seven loci, including rhg1a and Rhg4-a, involved in the resistance to SCN Hg type 5.7 were identified. To the best of our knowledge, two QTL (QTL-10 and QTL-19) were novel while three others (QTL-07, QTL-14 and QTL-20) were previously identified by other researchers. Based on statistical analyses, two loci, QTL-10 and QTL-20, seemed to be partial viable alternatives to the rhg1a and Rhg4-a loci as they were demonstrated to be effective in the Rhg1 and/or Rhg4 susceptible backgrounds. Using a four-step prediction pipeline, seven candidate genes (Glyma.07G196800, Glyma.07G199700, Glyma.07G203300, Glyma.07G206200, Glyma.14G019600, Glyma.14G025800, and Glyma.20G197600) were identified in the narrow regions of QTL-07, QTL-14 and QTL-20. Based on these predictions and a thorough literature review, we consider that Glyma.07G196800, Glyma.07G203300, and Glyma.07G206200 are the best candidates for QTL-07. In conclusion, our study strengthens our understanding of the genetic loci underlying SCN resistance and diversify the single nucleotide polymorphism marker catalog currently available to breeders.
Access status: Open Access ,
Evaluation of transmission metrics in a slow-spreading highly pathogenic avian influenza (HPAI) outbreak in a commercial upland game bird system
(Canadian Science Publishing, 2025-12-10) St. Charles, Kaitlyn M.; Ssematimba, Amos; Bonney, Peter; Cardona, Carol
In 2022, highly pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b was detected in United States (US) poultry, quickly escalating into an outbreak that surpassed the 2014/15 HPAI US event in scale and impact. Unlike in 2014/15, the 2022/3/4/5 outbreak has included numerous HPAI detections in previously infrequently affected commodities such as broilers and commercially-raised upland game birds. Here, we describe H5 HPAIV detections that occurred between December 2023 and January 2024 in a multi-premises upland game bird system located in the Midwestern US. We used an approximate Bayesian computation algorithm and stochastic within-flock HPAI transmission model to estimate the following: 1) times of HPAI introduction onto each affected premises, 2) number of days between estimate time of introduction and time of detection, and 3) the adequate contact rates and basic reproduction numbers within individual barns. Clinical signs and mortality observed in the infected pheasant flocks were largely consistent with other pheasant H5 clade 2.3.4.4b outbreaks. Across the system, the estimated transmission metrics were noticeably lower than those calculated from outbreaks in other poultry species. However, time to detection was similar to HPAI outbreaks that have occurred in other commodities.
Access status: Open Access ,
In vitro and in vivo anticancer efficacy of the combination of Actinomycin D and resveratrol
(Canadian Science Publishing, 2025-12-30) Raji, Lukmon M; Afrin, Rejina; Amin, Jihan Ferdaus; Lamichhane, Rajan; Denning, Krista L; AMIN, ARM
Actinomycin D (Act D) was the first FDA-approved anticancer antibiotic. However, its widespread application was hindered by dose-limiting toxicities. In the current study, we investigated the in vitro and in vivo anticancer efficacy of the combination of Act D with resveratrol. We found that the combination of Act D and resveratrol has better in vitro efficacy than any of the single agent. We also explored the underlying mechanism by investigating the activation of the p53 pathway. Consistent with the cell growth inhibition, Act D, resveratrol and their combination activated p53 and induced the expression of p21, PUMA and GDF15 mRNA and proteins. The combination had better effects than any of the single agents alone. Ablation of p53 significantly protected cells and confirmed p53-dependent expression of these genes. Finally, we investigated the in vivo efficacy of these agents and their combination using xenograft model. Act D, resveratrol and their combination significantly inhibited the growth of xenografts. The in vivo efficacy was further supported by Ki-67 expression in tumor tissues. Taken together, our findings demonstrated that although the combination of Act D and resveratrol showed better efficacy in vitro than any of the single agent, the in vivo efficacy was not improved.