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Abstract The zoonotic enterohemorrhagic Escherichia coli (EHEC) O157: H7 bacterium causes diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS) in humans. Cattle are primary reservoirs and EHEC O157: H7; the bacteria predominately inhabit the colon and recto-anal junctions (RAJ). The early innate immune reactions in the infected gut are critical in the pathogenesis of EHEC O157: H7. In this study, calves orally inoculated with EHEC O157: H7 showed infiltration of neutrophils in the lamina propria of ileum and RAJ at 7 and 14 days post-infection. Infected calves had altered mucin layer and mast cell populations across small and large intestines. There were differential transcription expressions of key bovine β defensins, tracheal antimicrobial peptide (TAP) in the ileum, and lingual antimicrobial peptide (LAP) in RAJ. The main Gram-negative bacterial/LPS signaling Toll-Like receptor 4 (TLR4) was downregulated in RAJ. Intestinal infection with EHEC O157: H7 impacted the gut bacterial communities and influenced the relative abundance of Negativibacillus and Erysipelotrichaceae in mucosa-associated bacteria in the rectum. Thus, innate immunity in the gut of calves showed unique characteristics during infection with EHEC O157: H7, which occurred in the absence of major clinical manifestations but denoted an active immunological niche.

Neospora caninum is recognised for causing cattle abortion, provoking severe economic losses in the livestock industry worldwide. The aim of the present study was to evaluate the reactivation and foetal infection in pregnant heifers inoculated with live N. caninum tachyzoites before puberty. A total of 15 30-month-old pregnant heifers were allocated into four groups: animals inoculated with live tachyzoites of NC-Argentina LP1 isolate before puberty and challenged with live tachyzoites of NC-1 strain at 210 days of gestation (DG) (Group A); animals mock inoculated before puberty and challenged with NC-1 strain at 210 DG (Group B), animals inoculated before puberty but not subsequently challenged (Group C); and noninfected and nonchallenged animals (Group D). The results of this study showed that 100% of animals infected before puberty (Groups A and C) suffered reactivation of the infection at the seventh month of gestation. In addition, in three and two calves from Groups A and C, respectively, congenital infection was confirmed. Interestingly, we provide evidence that the use of live N. caninum tachyzoites in young animals as a strategy to induce protection is neither safe nor effective.

Tuberculosis (TB) is one of the most potent infectious diseases in the world, causing more deaths than any other single infectious agent. TB infection is caused by inhalation of Mycobacterium tuberculosis (Mtb) and subsequent phagocytosis and migration into the lung tissue by innate immune cells (e.g., alveolar macrophages, neutrophils, and dendritic cells), resulting in the formation of a fused mass of immune cells known as the granuloma. Considered the pathological hallmark of TB, the granuloma is a complex microenvironment that is crucial for pathogen containment as well as pathogen survival. Disruption of the delicate granuloma microenvironment via numerous stimuli, such as variations in cytokine secretions, nutrient availability, and the makeup of immune cell population, can lead to an active infection. Herein, we present a novel in vitro model to examine the soluble factor signaling between a mycobacterial infection and its surrounding environment. Adapting a newly developed suspended microfluidic platform, known as Stacks, we established a modular microscale infection model containing human immune cells and a model mycobacterial strain that can easily integrate with different microenvironmental cues through simple spatial and temporal “stacking” of each module of the platform. We validate the establishment of suspended microscale (4 μL) infection cultures that secrete increased levels of proinflammatory factors IL-6, VEGF, and TNFα upon infection and form 3D aggregates (granuloma model) encapsulating the mycobacteria. As a proof of concept to demonstrate the capability of our platform to examine soluble factor signaling, we cocultured an in vitro angiogenesis model with the granuloma model and quantified morphology changes in endothelial structures as a result of culture conditions (P < 0.05 when comparing infected vs. uninfected coculture systems). We envision our modular in vitro granuloma model can be further expanded and adapted for studies focusing on the complex interplay between granulomatous structures and their surrounding microenvironment, as well as a complementary tool to augment in vivo signaling and mechanistic studies.

Bovine Herpesvirus type 5 (BoHV-5) has not been conclusively demonstrated to cause bovine abortion. Brain lesions produced by Neospora caninum and Bovine Herpesvirus type 1 (BoHV-1) exhibit common features. Therefore, careful microscopic evaluation and additional diagnostic procedures are required to achieve an accurate final etiological diagnosis. The aim of the present work was to investigate the occurrence of infections due to BoHV-1, BoHV-5 and N. caninum in 68 cases of spontaneous bovine abortions which showed microscopic lesions in the fetal central nervous system. This study allowed the identification of 4 (5.9%) fetuses with dual infection by BoHV-5 and N. caninum and 33 (48.5%) cases in which N. caninum was the sole pathogen identified. All cases were negative to BoHV-1. The results of this study provide evidence that dual infection by BoHV-5 and N. caninum occur during pregnancy in cattle; however, the role of BoHV-5 as a primary cause of bovine abortion needs further research. Molecular diagnosis of BoHV-5 and N. caninum confirmed the importance of applying complementary assays to improve the sensitivity of diagnosing bovine abortion.

To the Editor: Blood transcriptional profiling is a powerful tool to evaluate immune responses to infection; however, blood collection via traditional phlebotomy remains a barrier to precise characterization of the [...]

COVID-19 has affected healthcare in profound and unprecedented ways, distorting the experiences of patients and healthcare professionals (HCPs) alike. One area that has received little attention is how COVID-19 affected HCPs caring for dying patients. The goal of this study was to examine the experiences of HCPs working with dying patients during the COVID-19 pandemic. Between July 2020–July 2021, we recruited HCPs (N = 25) across Canada. We conducted semi-structured interviews, using a qualitative study design rooted in constructivist grounded theory methodology. The core themes identified were the impact of the pandemic on care utilization, the impact of infection control measures on provision of care, moral distress in the workplace, impact on psychological wellbeing, and adaptive strategies to help HCPs manage emotions and navigate pandemic imposed changes. This is the first Canadian study to qualitatively examine the experiences of HCPs providing care to dying patients during the COVID-19 pandemic. Implications include informing supportive strategies and shaping policies for HCPs providing palliative care. [ABSTRACT FROM AUTHOR]

Purpose The interplay between critical illness and mental disorders is poorly understood. The purpose of this study is to measure both the treated prevalence of mental disorders and psychotropic medication use before and after hospitalization and the impact of intensive care unit (ICU) admission on these outcomes. Methods Using a population-based administrative database in Manitoba, Canada, 49,439 ICU patients admitted between 2000 and 2012 were compared to two matched comparison groups (hospitalized; n = 146,968 and general population; n = 141,937). Treated prevalence of mental disorders and psychotropic medication prescriptions were measured in the 5-year periods before and after the hospitalization. Multivariable models compared adjusted prevalence ratios (APRs) between populations. Results The 5-year treated mental disorder prevalence in the ICU population increased from 41.5% pre-hospitalization to 55.6% post-hospitalization. Compared to non-ICU hospitalized patients, the adjusted treated mental disorder prevalence in ICU patients was lower prior to hospitalization (1-year APR 0.94, 95% CI 0.92-0.97, p < 0.0001; 5-year APR 0.99, 95% CI 0.98-1.00, p = 0.1), but higher following discharge (1-year APR 1.08, 95% CI 1.05-1.11, p < 0.0001, 5-year APR 1.03, 95% CI 1.01-1.05, p < 0.0001). A high proportion of ICU patients received antidepressant, anxiolytic and sedative-hypnotic prescriptions before and after their hospitalization. In multivariable analyses, ICU exposure was associated with an increase in mood, anxiety and psychotic disorders, and sedative-hypnotics use (p < 0.0001 for all Time x Group interactions). Conclusions During the 5 years after admission to ICU, there is a significant increase in treated prevalence of mental disorders and psychotropic medication use compared to the 5 years prior to ICU and compared to general population and hospital cohorts. Prevention and intervention programs that identify and treat mental disorders among survivors of critical illness warrant further study., Author(s): Kendiss Olafson [sup.1], Ruth Ann Marrie [sup.1] [sup.2], James M. Bolton [sup.2] [sup.3] [sup.4], Charles N. Bernstein [sup.1], O. Joseph Bienvenu [sup.5], Maia S. Kredentser [sup.6], Sarvesh Logsetty [sup.3] [...]

Sablefish (Anoplopoma fimbria) of the Northeast Pacific support a highly mobile, valuable fishery resource currently managed as three separate populations. Recent work has shown sablefish to be genetically mixed; have high movement rates; and have synchronous biomass trends, including recent declines. A management strategy evaluation was developed with stakeholders and scientists from three regions to investigate whether spatially structured management paradigms might result in better conservation and economic outcomes. The management strategy evaluation includes a transboundary operating model to represent spatial population dynamics including movement and a delay–difference estimation method with varying spatial complexities and potential stratifications, and harvest control rules. Mismatches in the spatial scale of management and the underlying biological units pose a crucial risk of localized depletion in the southern U.S. West Coast. This study presents one of the first transboundary, spatially-explicit management strategy evaluations conditioned to actual data. These results underscore the importance of spatial management strategy evaluation tools and implications when regional management is conducted in isolation. Future work should incorporate additional spatial hypotheses and investigate the drivers of recruitment patterns range-wide. [ABSTRACT FROM AUTHOR]

Deciding whether to forego immediate rewards or explore new opportunities is a key component of flexible behavior and is critical for the survival of the species. Although previous studies have shown that different cortical and subcortical areas, including the amygdala and ventral striatum (VS), are implicated in representing the immediate (exploitative) and future (explorative) value of choices, the effect of the motor system used to make choices has not been examined. Here, we tested male rhesus macaques with amygdala or VS lesions on two versions of a three-arm bandit task where choices were registered with either a saccade or an arm movement. In both tasks we presented the monkeys with explore-exploit tradeoffs by periodically replacing familiar options with novel options that had unknown reward probabilities. We found that monkeys explored more with saccades but showed better learning with arm movements. VS lesions caused the monkeys to be more explorative with arm movements and less explorative with saccades, although this may have been due to an overall decrease in performance. VS lesions affected the monkeys' ability to learn novel stimulus-reward associations in both tasks, while after amygdala lesions this effect was stronger when choices were made with saccades. Further, on average, VS and amygdala lesions reduced the monkeys' ability to choose better options only when choices were made with a saccade. These results show that learning reward value associations to manage explore-exploit behaviors is motor system dependent and they further define the contributions of amygdala and VS to reinforcement learning. [ABSTRACT FROM AUTHOR]