A nod to the bond between NOD2 and mycobacteria.

Mycobacteria are responsible for several human and animal diseases. NOD2 is a pattern recognition receptor that has an important role in mycobacterial recognition. However, the mechanisms by which mutations in NOD2 alter the course of mycobacterial infection remain unclear. Herein, we aimed to review the totality of studies directly addressing the relationship between NOD2 and mycobacteria as a foundation for moving the field forward. NOD2 was linked to mycobacterial infection at 3 levels: (1) genetic, through association with mycobacterial diseases of humans; (2) chemical, through the distinct NOD2 ligand in the mycobacterial cell wall; and (3) immunologic, through heightened NOD2 signaling caused by the unique modification of the NOD2 ligand. The immune response to mycobacteria is shaped by NOD2 signaling, responsible for NF-κB and MAPK activation, and the production of various immune effectors like cytokines and nitric oxide, with some evidence linking this to bacteriologic control. Absence of NOD2 during mycobacterial infection of mice can be detrimental, but the mechanism remains unknown. Conversely, the success of immunization with mycobacteria has been linked to NOD2 signaling and NOD2 has been targeted as an avenue of immunotherapy for diseases even beyond mycobacteria. The mycobacteria-NOD2 interaction remains an important area of study, which may shed light on immune mechanisms in disease.

Determinants of pain assessment documentation in intensive care units.

PURPOSE: The underassessment of pain is a major barrier to effective pain management, and the lack of pain assessment documentation has been associated with negative patient outcomes. This study aimed to 1) describe the contextual factors related to pain assessment and management in five Québec intensive care units (ICUs); 2) describe their pain assessment documentation practices; and 3) identify sociodemographic and clinical determinants related to pain assessment documentation. METHODS: A descriptive-correlational retrospective design was used. Sociodemographic data (i.e., age, sex), clinical data (i.e., diagnosis, mechanical ventilation, level of consciousness, severity of illness, opioids, sedatives), and pain assessments were extracted from 345 medical charts of ICU admissions from five teaching hospitals between 2017 and 2019. Descriptive statistics and multiple linear regression were performed. RESULTS: All sites reported using the 0-10 numeric rating scale, but the implementation of a behavioural pain scale was variable across sites. A median of three documented pain assessments were performed per 24 hr, which is below the minimal recommendation of eight to 12 pain assessments per 24 hr. Overall, pain assessment was present in 70% of charts, but only 20% of opioid doses were followed by documented pain reassessment within one hour post-administration. Higher level of consciousness (ß = 0.37), using only breakthrough doses (ß = 0.24), and lower opioid doses (ß = -0.21) were significant determinants of pain assessment documentation (adjusted R2 = 0.25). CONCLUSION: Pain assessment documentation is suboptimal in ICUs, especially for patients unable to self-report or those receiving higher opioid doses. Study findings highlight the need to implement tools to optimize pain assessment and documentation.

RéSUMé: OBJECTIF: La sous-évaluation de la douleur constitue un obstacle majeur à une gestion efficace de la douleur, et le manque de documentation de l'évaluation de la douleur a été associé à des conséquences défavorables pour les patients. Cette étude visait à : 1) décrire les facteurs contextuels liés à l'évaluation et à la gestion de la douleur dans cinq unités de soins intensifs (USI) du Québec; 2) décrire leurs pratiques de documentation de l'évaluation de la douleur; et 3) identifier les déterminants sociodémographiques et cliniques liés à la documentation de l'évaluation de la douleur. MéTHODE: Un devis de recherche rétrospectif descriptif-corrélationnel a été utilisé. Les données sociodémographiques (c.-à-d. l'âge, le sexe), les données cliniques (c.-à-d. le diagnostic, la ventilation mécanique, le niveau de conscience, la gravité de la maladie, les opioïdes, les sédatifs) et les évaluations de la douleur ont été extraites de 345 dossiers médicaux avec admissions à l'USI de cinq hôpitaux universitaires entre 2017 et 2019. Des statistiques descriptives et une régression linéaire multiple ont été effectuées. RéSULTATS: Tous les sites ont déclaré utiliser l'échelle d'évaluation numérique de 0 à 10, mais l'implantation d'une échelle de douleur comportementale variait d'un site à un autre. Une médiane de trois évaluations de douleur étaient documentées par 24 heures, ce qui est inférieur à la recommandation minimale de huit à 12 évaluations de douleur par 24 heures. Dans l'ensemble, l'évaluation de la douleur était présente dans 70 % des dossiers, mais seulement 20 % des doses d'opioïdes étaient suivies d'une réévaluation documentée de la douleur dans l'heure suivant leur'administration. Un niveau de conscience plus élevé (ß = 0,37), l'utilisation exclusive d'entredoses d'opioïdes pour les percées de douleur (ß = 0,24) et des doses d'opioïdes plus faibles (ß = -0,21) ont constitué les déterminants significatifs dans la documentation de l'évaluation de la douleur (R2 ajusté = 0,25). CONCLUSION: La documentation de l'évaluation de la douleur est sous-optimale dans les USI, en particulier pour les patients incapables de s'exprimer ou ceux qui reçoivent des doses plus élevées d'opioïdes. Les résultats de cette étude soulignent l'importance d'implanter des outils pour optimiser l'évaluation et la documentation de la douleur.

Analysis of implementation outcomes of quality improvement initiatives in Haiti: the fingerprint initiative.

OBJECTIVE: To assess the process and outcomes of the implementation of an electronic fingerprint initiative as part of quality improvement in three health facilities in the Northern Department of Haiti, in terms of its acceptability, adoption, feasibility, fidelity, and sustainability. In Haiti, poor attendance of the healthcare workforce is a nationwide problem, closely related to the quality of care. Three health institutions have tried to implement an electronic fingerprint system to monitor and improve attendance. METHODS: An exploratory and qualitative descriptive study of the implementation outcomes of the fingerprint initiative. It was based on semi-structured interviews and one group discussion using purposeful sampling techniques to recruit participants, and an open coding system and deductive approach to analyze the data using ATLAS.ti 8. RESULTS: The fingerprint initiative was successfully implemented in a non-governmental organization supported health facility but, despite some planning, it was never implemented in the public health facilities. The acceptability of the implementation was high in the not-for-profit organization and low in the public settings, mostly in relation to the presence of champions and the leadership at each health facility. CONCLUSIONS: We recommend more involvement of the leadership of health facilities in the different phases of the implementation process in order to guarantee acceptability, adoption, fidelity and sustainabiliy. More research is needed to articulate this technology-driven initiative in the Haitian health system.

The influence of blood on the human gut microbiome.

BACKGROUND: Colorectal cancer (CRC) is one of the prevailing causes of cancer mortality in the world. A common screening test for CRC is based on the human hemoglobin immunochemical based fecal occult blood test (iFOBT), which consists in the detection of blood in the patient's stool. In addition to iFOBT, recent studies support the use of the gut microbiome as a biomarker for CRC prediction. However, these studies did not take into account the effect of blood itself on the microbiome composition, independently of CRC. Therefore, we investigated the microbiome of patients undergoing the iFOBT screening in order to determine the effect of blood alone. Our cohort consisted of patients who had no blood in their stools (n = 265) or did have blood but no underlying precancerous or cancerous lesions (n = 235). We also identified bacterial taxa specifically associated with the presence of blood in stools. RESULTS: We observed significant differences in the intestinal bacterial composition that could be solely caused by the presence of blood in stools. More precisely, we identified 12 bacterial species showing significant differences in abundance between both our study groups. These species, Bacteroides uniformis, Collinsella aerofaciens, Eggerthella lenta and Clostridium symbiosum demonstrated increased abundance in the presence of blood. In contrast, the species Prevotella copri, Coprococcus eutactus and catus, Faecalibacterium prausnitzii, Roseburia faecis, Blautia obeum, Gemmiger formicilis and Clostridium celatum showed decreased abundance in patients with blood in their stools. Notably, we found multiple taxa that were reported in previous studies linking microbiome composition and diseases. CONCLUSIONS: We show that, in the absence of disease, blood in the stools has a major influence on the composition of the microbiome. Our data suggest that blood itself should be taken into consideration when investigating the microbiome signatures of intestinal diseases.

An EMR-Based Alert with Brief Provider-Led ART Adherence Counseling: Promising Results of the InfoPlus Adherence Pilot Study Among Haitian Adults with HIV Initiating ART.

To promote HIV antiretroviral therapy (ART) outcomes in Haiti, we developed a culturally relevant intervention (InfoPlus Adherence) that combines an electronic medical record alert identifying patients at elevated risk of treatment failure and provider-delivered brief problem-solving counseling. We conducted a quasi-experimental mixed-methods study among 146 patients at two large ART clinics in Haiti with 728 historical controls. We conducted quantitative assessments of patients at baseline and intervention completion (6 months) as well as focus groups with health workers and exit interviews with patients. The primary quantitative outcome measures were HIV viral suppression according to medical record and ART adherence in terms of ≥ 90% for "proportion of days covered" (PDC) according to pharmacy dispensing data. Results indicated that the proportion of intervention patients with suppressed VL during the study/historical periods was 80.0%/86.0% and 76.8%/87.4% for controls. In a difference-in-differences (DID) analytic model, the adjusted relative risk for viral suppression with the intervention was 1.15 (95% CI 0.92-1.45, p = 0.21), representing favorable but non-significant association between the intervention and the trajectory of VL outcomes. PDC ≥ 90% during the study/historical periods was 30.9%/11.0% among intervention participants and 16.9%/19.4% among controls. In the adjusted DID model, the relative risk for of PDC ≥ 90% with the intervention was 4.00 (95% CI 1.91-8.38, p < 0.001), representing a highly favorable association between the intervention and the trajectory of PDC outcomes. Qualitative data affirmed acceptability of the intervention, although providers reported some challenges consistently implementing it. Future research is needed to demonstrate efficacy and explore optimal implementation strategies.

Albumin/Creatinine Ratio for the Detection of Significant Proteinuria of Preeclampsia in Hospitalized Hypertensive Women.

OBJECTIVE: Preeclampsia is a hypertensive disorder of pregnancy associated with proteinuria detected by 24-hour urine collection (≥0.3 g/24 h) or protein/creatinine ratio (≥30 mg/mmol). The albumin/creatinine ratio (ACR) is used outside pregnancy to detect abnormal amounts of albumin in the urine, but there is little data on its value in pregnancy. Our objective was to determine the diagnostic threshold for ACR to detect significant proteinuria in women investigated for preeclampsia. METHODS: A prospective observational study involving 99 hypertensive women (≥140/90 mm Hg) over 20 weeks gestation who were hospitalized at 2 Canadian tertiary centres. A 24-hour urine collection and a morning urine sample were collected. The optimal ACR threshold was determined by a receiver operating characteristic (ROC) curve using the 24-hour collection as the reference test; sensitivity and specificity analyses were performed. Maternal and perinatal characteristics were extracted from medical records. RESULTS: Of the 87 women who had completed urine collection, 74 (85%) had an initial diagnosis of preeclampsia and 63 (72%) had significant proteinuria confirmed by 24-hour collection. The area under the morning ROC curve was 0.92 (95% CI 0.86-0.98) and the optimal threshold obtained for the ACR was 9 mg/mmol, with a sensitivity and specificity of 84% (95% CI 73-92) and 88% (95% CI 68-97), respectively. CONCLUSION: Our results suggest that an ACR threshold of 9 mg/mmol on a morning urine sample can be used to detect significant proteinuria of preeclampsia in hospitalized hypertensive women.

Examining perceptions from in situ simulation-based training on interprofessional collaboration during crisis event management in post-anesthesia care.

Due to the potentially life-threatening conditions and risk of severe complications, post-anesthesia care units (PACU) require prompt team interventions. Miscommunication among professionals during crisis event management may directly affect patient safety. Therefore, developing strategies to enhance interprofessional collaboration (IPC) among critical care teams should be prioritized. In situ simulation (ISS) can be valuable in improving patient safety because it allows the practice of care team dynamics within a real clinical environment. However, its impact on IPC has yet to be demonstrated. The aim of this study was to evaluate the effect of in situ simulation-based training on interprofessional collaboration and satisfaction toward co-workers during crisis event management in post-anesthesia care. A quasi-experimental study, pretest and post-test design with a paired control group was performed. A convenience sample (N = 69) was recruited from the healthcare professionals of the regular PACU team. The intervention group (N = 33) underwent a 6-hour ISS-based interprofessional training session. Three scenarios of deteriorating cases encountered in critical care settings were used, each followed by a debriefing period. The measured outcomes were evaluated by the Collaborative Work Questionnaire and the Satisfaction Towards Coworkers Questionnaire. Questionnaires were answered by the two groups before the intervention (T1), immediately after (T2) and six to eight weeks later (T3). We found that the change from baseline (T1) was different between the groups for global IPC (F = 3.88; p = 0.025) and for communication (F = 4.09; p = 0.021). Regarding global IPC, we observed a significant group effect from T1 to T2 (F = 5.65; p = 0.021) and from T1 to T3 (F = 5.34; p = 0.024). Furthermore, we observed a significant time effect for the experimental group (F = 4.06; p = 0.027). Regarding communication, we observed a significant group effect from T1 to T2 (F = 7.5; p = 0.001). In conclusion, ISS-based training had a slight impact on self-assessed IPC and communication during crisis event management in the PACU. The use of ISS should be promoted among critical care teams to enhance IPC and contribute to patient safety.

Imaging of Post Transthoracic Needle Biopsy Complications.

When faced with characterization of a suspicious lung lesion, transthoracic needle biopsy (TTNB) is the standard technique used to retrieve a pathological specimen. Usual complications reported for this intervention are pneumothorax, hemorrhage, air embolism, and tumor seeding. This pictorial essay illustrates imaging of these complications.

Lovastatin corrects ERK pathway hyperactivation in fragile X syndrome: potential of platelet's signaling cascades as new outcome measures in clinical trials.

AIM: To establish whether platelets from fragile X syndrome (FXS) individuals recapitulate FXS mouse neurons' defects in ERK and Akt pathways, and to evaluate the effect of lovastatin on these pathways. METHODS: ERK and Akt phosphorylation (pERK, pAkt) statuses were assessed with quantitative Western blotting before and after a 12-week lovastatin trial. RESULTS: Levels of pERK and pAkt were increased in FXS platelets, and lovastatin specifically normalized ERK activity. Changes in ERK phosphorylation were correlated with clinical response to lovastatin. CONCLUSIONS: Platelets' signaling pathways provide biomarkers that can be used as treatment outcome measures in FXS clinical trials.

Informational role self-efficacy: a validation in interprofessional collaboration contexts involving healthcare service and project teams.

BACKGROUND: Healthcare professionals perform knowledge-intensive work in very specialized disciplines. Across the professional divide, collaboration becomes increasingly difficult. For effective teamwork and collaboration to occur, it is considered necessary for individuals to believe in their ability to draw on their expertise and provide what others need to perform their job well. To date, however, no instruments exist to measure such a construct. METHODS: A two-study design is used to test the psychometric properties, factor structure and incremental validity of a five-item questionnaire measuring informational role self-efficacy. RESULTS: Based on parallel analysis and exploratory factor analysis, Study 1 shows a robust and reliable one-dimensional construct. Study 2 cross-validates this factor structure using confirmatory factor analysis. Study 2 also shows that informational role self-efficacy predicts proactive teamwork behaviors over and above goal similarity, interdependence, coordination and intra-team trust. CONCLUSIONS: The instrument can be used in research to assess an individual's capability beliefs in communicating his/her informational characteristics that are pertinent to the task performance of others. The construct is also shown to have value in team-building exercises.

Contribution of environmental determinants to the risk of developing type 2 diabetes mellitus in a life-course perspective: a systematic review protocol.

BACKGROUND: Prevention policies against type 2 diabetes mellitus (T2DM) focus solely on individual healthy lifestyle behaviours, while an increasing body of research recognises the involvement of environmental determinants (ED) (cultural norms of land management and planning, local foodscape, built environment, pollution, and neighbourhood deprivation). Precise knowledge of this relationship is essential to proposing a prevention strategy integrating public health and spatial planning. Unfortunately, issues related to the consistency and synthesis of methods, and results in this field of research limit the development of preventive strategies. This systematic review aims to improve knowledge about the relationship between the risk of developing T2DM in adulthood and long-term exposure to its ED during childhood or teenage years. METHODS: This protocol is presented according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) tools. PubMed, Embase, CINAHL, Web of Science, EBSCO, and grey literature from the Laval University Libraries databases will be used for data collection on main concepts such as 'type 2 diabetes mellitus', 'zoning' or 'regional, urban, or rural areas land uses', 'local food landscape', 'built environment', 'pollution', and 'deprivation'. The Covidence application will store the collected data for selection and extraction based on the Population Exposure Comparator Outcome and Study design approach (PECOS). Studies published until December 31, 2023, in English or French, used quantitative data about individuals aged 18 and over that report on T2DM, ED (cultural norms of land management and planning, local foodscape, built environment, and neighbourhood deprivation), and their association (involving only risk estimators) will be included. Then, study quality and risk of bias will be conducted according to the combined criteria and ratings from the ROBINS-E (Risk of Bias in Non-randomised Studies-of Exposures) tools and the 'Effective Public Health Practice Project' (EPHPP). Finally, the analytical synthesis will be produced using the 'Synthesis Without Meta-analysis' (SWiM) guidelines. DISCUSSION: This systematic review will summarise available evidence on ED associated with T2DM. The results will contribute to improving current knowledge and developing more efficient cross-sectoral interventions in land management and public health in this field of research. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023392073.

Optimizing Fecal Occult Blood Test (FOBT) Colorectal Cancer Screening Using Gut Bacteriome as a Biomarker.

BACKGROUND: Colorectal cancer (CRC) is a major cause of cancer mortality in the world. One of the most widely used screening tests for CRC is the immunochemical fecal occult blood test (iFOBT), which detects human hemoglobin from patient's stool sample. Although it is highly efficient in detecting blood from patients with gastro-intestinal lesions, such as polyps and cancers, the iFOBT has a high rate of false positive discovery. Recent studies suggested gut bacteria as a promising noninvasive biomarker for improving the diagnosis of CRC. In this study, we examined the composition of gut bacteria using iFOBT leftover from patients undergoing screening test along with a colonoscopy. METHODS: After collecting data from more than 800 patients, we considered 4 groups for this study. The first and second groups were respectively "healthy" in which the patients had either no blood in their stool or had blood but no lesions. The third and fourth groups of patients had both blood in their stools with precancerous and cancerous lesions and considered either as low-grade and high-grade lesion groups, respectively. An amplification of 16S rRNA (V4 region) gene was performed, followed by sequencing along with various statistical and bioinformatic analysis. RESULTS: We analyzed the composition of the gut bacteriome at phylum, class, genus, and species levels. Although members of the Firmicute phylum increased in the 3 groups compared to healthy patients, the phylum Actinobacteriota was found to decrease. Moreover, Blautia obeum and Anaerostipes hadrus from the phylum Firmicutes were increased and Collinsella aerofaciens from phylum Actinobacteriota was found decreased when healthy group is compared to the patients with high-grade lesions. Finally, among the 5 machine learning algorithms used to perform our analysis, both elastic net (AUC > 0.7) and random forest (AUC > 0.8) performs well in differentiating healthy patients from 3 other patient groups having blood in their stool. CONCLUSION: Our study integrates the iFOBT screening tool with gut bacterial composition to improve the prediction of CRC lesions.

Structure and mechanical properties of spider silk films at the air-water interface.

The kinetics of adsorption of solubilized spider major ampullate (MA) silk fibers at the air-water interface and the molecular structure and mechanical properties of the interfacial films formed have been studied using various physical techniques. The data show that Nephila clavipes MA proteins progressively adsorb at the interface and ultimately form a highly cohesive thin film. In situ infrared spectroscopy shows that as soon as they reach the interface the proteins predominantly form ß sheets. The protein secondary structure does not change significantly as the film grows, and the amount of ß sheet is the same as that of the natural fiber. This suggests that the final ß-sheet content is mainly dictated by the primary structure and not by the underlying formation process. The measure of the shear elastic constant at low strain reveals a very strong, viscous, cohesive assembly. The ß sheets seem to form cross-links dispersed within an intermolecular network, thus probably playing a major role in the film strength. More importantly, the molecular weight seems to be a crucial factor because interfacial films made from the natural proteins are ~7 times stronger and ~3 times more viscous than those obtained previously with shorter recombinant proteins. Brewster angle microscopy at the air-water interface and transmission electron microscopy of transferred films have revealed a homogeneous organization on the micrometer scale. The images suggest that the structural assembly at the air-water interface leads to the formation of macroscopically solid and highly cohesive networks. Overall, the results suggest that natural spider silk proteins, although sharing similarities with recombinant proteins, have the particular ability to self-assemble into ordered materials with exceptional mechanical properties.

Human keratinocytes respond to direct current stimulation by increasing intracellular calcium: preferential response of poorly differentiated cells.

A direct current (DC) endogenous electric field (EF) is induced in the wound following skin injury. It is potentially implicated in the wound healing process by attracting cells and altering their phenotypes as indicated by the response to an EF of keratinocytes cultured as individual cells. To better define the signalization induced by a direct current electric field (DCEF) in human keratinocytes, we took advantage of an in vitro model more representative of the in vivo situation since it promotes cell-cell interactions and stratification. Human keratinocytes were grown into colonies. Their exposure to a DCEF of physiological intensity induced an increase of intracellular calcium. This variation of intracellular calcium resulted from an extracellular calcium influx and was mediated, at least in part, by the L-type voltage-gated calcium channel. The increase in intracellular calcium in response to a DCEF was however not observed in all the cells composing the colonies. The intracellular calcium increase was only detected in keratinocytes that didn't express involucrin, a marker of differentiated cells. These results indicate that DCEF is able to induce a specific calcium response in poorly differentiated keratinocytes. This study brings a new perspective for the understanding of the signaling mechanism of endogenous EF in reepithelialization, a critical process during skin wound healing.

Regional variation in the modeling of donation frequency: the case of Héma-Québec, Canada.

BACKGROUND: Many studies on factors that can affect the frequency of blood donation have shown the influence of several individual characteristics. However, few studies have analyzed regional variations in blood donation frequency. The objective of this article is to verify to what extent individual and geographic variables influence blood donation in the Province of Québec, Canada. STUDY DESIGN AND METHODS: This article used a database provided by Héma-Québec (the organization in charge of blood collection in Québec), which included 426,247 donors, who made 1.4 million donations over a period of 5 years. Using the donors' residential postal codes and those of the blood collection sites, we created two geographic variables: the distance between the donor's place of residence and his or her collection site and each donor's region of residence. We subsequently modeled the frequency of blood donation and the different donor categories (based on the number of blood donations) using both a negative binomial regression model and an ordinal logistic regression model. RESULTS: The results indicate that, once the individual characteristics have been taken into account, the geographic variables, including proximity to the collection site, have a significant impact on the frequency of blood donation. Likewise, according to the results of the negative binomial model, among the 17 regions in the Province of Québec, there are five regions where blood donation incidence rate ratios (IRRs) are very high, that is, Abitibi-Témiscamingue (IRR, 1.77; 95% confidence interval [CI], 1.61-1.95); Bas-Saint-Laurent (IRR, 1.75; 95% CI, 1.59-1.93); Saguenay-Lac-Saint-Jean (IRR, 1.68; 95% CI, 1.53-1.84); Centre-du-Québec (IRR, 1.66; 95% CI, 1.51-1.83); and Chaudière-Appalaches (IRR, 1.62; 95% CI, 1.48-1.78). CONCLUSION: Such knowledge of the geography of blood donations makes it possible to better target certain regions when planning new blood drives, to ensure a constant blood supply.

Mice Dually Disrupted for Nod2 and Mincle Manifest Early Bacteriological Control but Late Susceptibility During Mycobacterium tuberculosis Infection.

Pattern recognition receptors Mincle and NOD2 have been implicated in mycobacterial immunity. However, knockout (KO) animal infection studies with Mycobacterium tuberculosis (Mtb) have had mild/delayed phenotypes. Given that genetic susceptibility to infectious diseases can be polygenic, we hypothesized that murine double knockout (DKO) of Mincle and Nod2 would result in exacerbation of altered immunity to mycobacterial infection leading to a more extreme phenotype than either KO alone. To test this hypothesis, we monitored bacterial burden, immune responses and survival following in vivo infections with Mtb in DKO mice for comparison to wildtype (WT) and single KOs. Bacterial burden and immune responses were not significantly affected at 3 and 6 weeks after infection in all mutant mice. At later timepoints, Nod2-KO mice had reduced survival compared to wildtype mice, and Mincle-KO survival was intermediate. Unexpectedly, dual disruption had no further effect; rather, DKO mice phenocopied Nod2-KO mice. We observed that Mtb-related death, exclusively in mice with disrupted Nod2, was accompanied by greater pulmonary cell death and distinct large necrotic foci. Therefore, determining how these receptors contribute to mycobacterial resistance will require analysis of immunophenotypes and their consequences on host pathology.

Revisiting Pierre Gy's formula (TOS) - A return to size-density classes for applications to contaminated soils, coated particular aggregates and mixed material systems.

For some real-world material systems, estimations of the incompressible sampling variance based on Gy's classical s2(FSE) formula from the Theory of Sampling (TOS) show a significant discrepancy with empirical estimates of sampling variance. In instances concerning contaminated soils, coated particular aggregates and mixed material systems, theoretical estimates of sampling variance are larger than empirical estimates, a situation which does not have physical meaning in TOS. This has led us to revisit the development of estimates of s2(FSE) from this famous constitutional heterogeneity equation and explore the use of size-density classes for mixed material systems (mixtures of both analyte-enriched and coated particles), an approach which has been mostly unused since Gy's original derivation. This approach makes it possible to avoid taking into account the granulometric and liberation factors from Gy's classical treatment, and present grounds for criticising the use of 'standard' input values of critical parameters such as f: = 0.5, and g: = 0.25. But, as always, the "liberation factor" (l) issue still plays an important role, which is paid due attention. The constitutional heterogeneity formula based on size-density classes is presented in a form that allows for easy implementation in practice, within specified limitations. We present extensive experimental results from real-world systems. Using the "SDCD model" with published data reproduced the relative sampling variances calculated for the standard "mineral-like matrices", but more importantly corrected the relative sampling variance calculated for real contaminants by several orders of magnitudes. In all cases, the recalculated relative sampling variances were decreased to below their corresponding experimental measurements, now fully as expected from TOS, substantiating our development.

Paving the way for invasive species: road type and the spread of common ragweed (Ambrosia artemisiifolia).

Roads function as prime habitats and corridors for invasive plant species. Yet despite the diversity of road types, there is little research on the influence of these types on the spread of invaders. Common ragweed (Ambrosia artemisiifolia), a plant producing large amounts of allergenic pollen, was selected as a species model for examining the impact of road type on the spread of invasive plants. We examined this relationship in an agricultural region of Quebec, Canada. We mapped plant distribution along different road types, and constructed a model of species presence. Common ragweed was found in almost all sampling sites located along regional (97%) and local paved (81%) roads. However, verges of unpaved local roads were rarely (13%) colonized by the plant. A model (53% of variance explained), constructed with only four variables (paved regional roads, paved local roads, recently mown road verges, forest cover), correctly predicted (success rate: 89%) the spatial distribution of common ragweed. Results support the hypothesis that attributes associated with paved roads strongly favour the spread of an opportunistic invasive plant species. Specifically, larger verges and greater disturbance associated with higher traffic volume create propitious conditions for common ragweed. To date, emphasis has been placed on controlling the plant in agricultural fields, even though roadsides are probably a much larger seed source. Strategies for controlling the weed along roads have only focused on major highways, even though the considerable populations along local roads also contribute to the production of pollen. Management prioritizations developed to control common ragweed are thus questionable.

Sampling particulate matter for analysis - Controlling uncertainty and bias using the theory of sampling.

Sampling particulate matter for measuring the content of an analyte is a routine operation in many fields of engineering and science. However, sampling can lead to important bias and variance in concentration estimation because of sampling errors stemming from particulate matter heterogeneity. The goal of this study was to quantify bias, reproducibility and the degree of representativeness of a probabilistic sampling (PS) technique following principles from the Theory of sampling (TOS) and grab sampling (GS). PS was designed to control sampling errors, while GS did not exert any control over them. GS also included a step of sieve screening, which is common during sampling in some fields (e.g. soil sampling). Both techniques were used with two different analytes, namely steel microspheres and copper sulfate, at two different concentrations, in order to assess sampling errors and sampling performance. The sampling method had the most significant effect on sampling bias and relative variance, and therefore, on the degree of sampling representativeness. The most important result is the demonstration that probabilistic sampling improves the degree of representativeness of concentrations measurements by more than two orders of magnitudes by significantly decreasing bias and relative variance. The lot containing the physical analyte lead to larger bias and relative variance compared to the lot containing the chemical analyte. GS resulted in largely biased results and a poor degree of representativeness. The results have also highlighted a significant problem associated with the screening of larger particles as performed in GS. This alteration of the primary sample decreased the variability of the resulting concentration measurements, but it also biased them significantly.

Underwhelming or Misunderstood? Genetic Variability of Pattern Recognition Receptors in Immune Responses and Resistance to Mycobacterium tuberculosis.

Human genetic control is thought to affect a considerable part of the outcome of infection with Mycobacterium tuberculosis (Mtb). Most of us deal with the pathogen by containment (associated with clinical "latency") or sterilization, but tragically millions each year do not. After decades of studies on host genetic susceptibility to Mtb infection, genetic variation has been discovered to play a role in tuberculous immunoreactivity and tuberculosis (TB) disease. Genes encoding pattern recognition receptors (PRRs) enable a consistent, molecularly direct interaction between humans and Mtb which suggests the potential for co-evolution. In this review, we explore the roles ascribed to PRRs during Mtb infection and ask whether such a longstanding and intimate interface between our immune system and this pathogen plays a critical role in determining the outcome of Mtb infection. The scientific evidence to date suggests that PRR variation is clearly implicated in altered immunity to Mtb but has a more subtle role in limiting the pathogen and pathogenesis. In contrast to 'effectors' like IFN-γ, IL-12, Nitric Oxide and TNF that are critical for Mtb control, 'sensors' like PRRs are less critical for the outcome of Mtb infection. This is potentially due to redundancy of the numerous PRRs in the innate arsenal, such that Mtb rarely goes unnoticed. Genetic association studies investigating PRRs during Mtb infection should therefore be designed to investigate endophenotypes of infection - such as immunological or clinical variation - rather than just TB disease, if we hope to understand the molecular interface between innate immunity and Mtb.