Explore the vast range of titles available.

Nucleotide-binding oligomerization domain 2 (NOD2) is an intracellular pattern recognition receptor that senses bacterial peptidoglycan (PGN)-conserved motifs in cytosol and stimulates host immune response. The association of NOD2 mutations with a number of inflammatory pathologies, including Crohn disease (CD), Graft-versus-host disease (GVHD), and Blau syndrome, highlights its pivotal role in host-pathogen interactions and inflammatory response. Stimulation of NOD2 by its ligand (muramyl dipeptide) activates pro-inflammatory pathways such as nuclear factor-κB (NF-κB), mitogen-activated protein kinases (MAPKs), and Caspase-1. A loss of NOD2 function may result in a failure in the control of microbial infection, thereby initiating systemic responses and aberrant inflammation. Because the ligand of Nod2 is conserved in both gram-positive and gram-negative bacteria, NOD2 detects a wide variety of microorganisms. Furthermore, current literature evidences that NOD2 is also able to control viruses' and parasites' infections. In this review, we present and discuss recent developments about the role of NOD2 in shaping the gut commensal microbiota and pathogens, including bacteria, viruses, and parasites, and the mechanisms by which Nod2 mutations participate in disease occurrence.

Background Rodents are recognized as hosts for at least 60 zoonotic diseases and may represent a serious threat for human health. In the context of global environmental changes and increasing mobility of humans and animals, contacts between pathogens and potential animal hosts and vectors are modified, amplifying the risk of disease emergence. An accurate identification of each rodent at a specific level is needed in order to understand their implications in the transmission of diseases. Among the Muridae, the Rattini tribe encompasses 167 species inhabiting South East Asia, a hotspot of both biodiversity and emerging and re-emerging diseases. The region faces growing economical development that affects habitats, biodiversity and health. Rat species have been demonstrated as significant hosts of pathogens but are still difficult to recognize at a specific level using morphological criteria. DNA-barcoding methods appear as accurate tools for rat species identification but their use is hampered by the need of reliable identification of reference specimens. In this study, we explore and highlight the limits of the current taxonomy of the Rattini tribe. Results We used the DNA sequence information itself as the primary information source to establish group membership and estimate putative species boundaries. We sequenced two mitochondrial and one nuclear genes from 122 rat samples to perform phylogenetic reconstructions. The method of Pons and colleagues (2006) that determines, with no prior expectations, the locations of ancestral nodes defining putative species was then applied to our dataset. To give an appropriate name to each cluster recognized as a putative species, we reviewed information from the literature and obtained sequences from a museum holotype specimen following the ancient DNA criteria. Conclusions Using a recently developed methodology, this study succeeds in refining the taxonomy of one of the most difficult groups of mammals. Most of the species expected within the area were retrieved but new putative species limits were also indicated, in particular within Berylmys and Rattus genera, where future taxonomic studies should be directed. Our study lays the foundations to better investigate rodent-born diseases in South East Asia and illustrates the relevance of evolutionary studies for health and medical sciences.

Background Hirschsprung’s disease (HSCR) is a serious congenital bowel disorder with a prevalence of 1/5000. Currently, there is a lack of systematically developed guidelines to assist clinical decision-making regarding diagnostics and management. Aims This guideline aims to cover the diagnostics and management of rectosigmoid HSCR up to adulthood. It aims to describe the preferred approach of ERNICA, the European Reference Network for rare inherited and congenital digestive disorders. Methods Recommendations within key topics covering the care pathway for rectosigmoid HSCR were developed by an international workgroup of experts from 8 European countries within ERNICA European Reference Network from the disciplines of surgery, medicine, histopathology, microbiology, genetics, and patient organization representatives. Recommendation statements were based on a comprehensive review of the available literature and expert consensus. AGREE II and GRADE approaches were used during development. Evidence levels and levels of agreement are noted. Results Thirty-three statements within 9 key areas were generated. Most recommendations were based on expert opinion. Conclusion In rare or low-prevalence diseases such as HSCR, there remains limited availability of high-quality clinical evidence. Consensus-based guidelines for care are presented.

Chemical staining methods, while reliable, are time consuming and can be resource-intensive, involving costly chemical reagents and raising environmental concerns. This underscores the compelling need for alternative solutions such as virtual staining, which not only accelerates the diagnostic process but also enhances the flexibility of stain applications without the associated physical and chemical costs. Generative artificial intelligence technologies prove to be immensely useful in addressing these challenges. However, in healthcare, particularly within computational pathology, the high-stakes nature of decisions complicates the adoption of these tools due to their often opaque processes. Our work introduces an innovative approach that harnesses generative models for virtual stain transformations, improving performance, trustworthiness, scalability, and adaptability within computational pathology. The core of the proposed methodology involves a singular Hematoxylin and Eosin (H&E) encoder that supports multiple stain decoders. This design prioritizes critical regions in the latent space of H&E tissues, leading to a richer representation that enables precise synthetic stain generation by the decoders. Tested to simultaneously generate eight different stains from a single H&E slide, our method also offers significant scalability benefits for routine use by loading only necessary model components during production. We integrate label-free knowledge during training, using loss functions and regularization to minimize artifacts, thereby enhancing the accuracy of virtual staining in both paired and unpaired settings. To build trust in these synthetic stains, we employ a real-time self-inspection methodology using trained discriminators for each stain type, providing pathologists with confidence heatmaps to aid in their evaluations. In addition, we perform automatic quality checks on new H&E slides to ensure that they conform to the trained H&E distribution, guaranteeing the generation of high-quality synthetic stained slides. Recognizing the challenges pathologists face in adopting new technologies, we have encapsulated our method in an open-source, cloud-based proof-of-concept system. This system enables users to easily and virtually stain their H&E slides through a browser, eliminating the need for specialized technical knowledge and addressing common hardware and software challenges. It also facilitates real-time user feedback integration. Lastly, we have curated a novel dataset comprising eight different paired H&E/stains related to pediatric Crohn’s disease at diagnosis, providing 30 whole slide images (WSIs) for each stain set (total of 480 WSIs) to stimulate further research in computational pathology.

Crohn disease (CD) is a multifactorial disease in which an abnormal immune response in the gastrointestinal (GI) tract leads to chronic inflammation. The small intestine, particularly the ileum, of patients with CD is colonized by adherent-invasive E. coli (AIEC)--a pathogenic group of E. coli able to adhere to and invade intestinal epithelial cells. As the earliest inflammatory lesions are microscopic erosions of the epithelium lining the Peyer's patches (PPs), we investigated the ability of AIEC bacteria to interact with PPs and the virulence factors involved. We found that AIEC bacteria could interact with mouse and human PPs via long polar fimbriae (LPF). An LPF-negative AIEC mutant was highly impaired in its ability to interact with mouse and human PPs and to translocate across monolayers of M cells, specialized epithelial cells at the surface of PPs. The prevalence of AIEC strains harboring the lpf operon was markedly higher in CD patients compared with controls. In addition, increased numbers of AIEC, but not LPF-deficient AIEC, bacteria were found interacting with PPs from Nod2(-/-) mice compared with WT mice. In conclusion, we have identified LPF as a key factor for AIEC to target PPs. This could be the missing link between AIEC colonization and the presence of early lesions in the PPs of CD patients.

Tracheal cytotoxin (TCT) was originally described as the minimal effector that was able to reproduce the cytotoxic response of Bordetella pertussis on ciliated epithelial cells. This molecule triggers pleiotropic effects such as immune stimulation or slow‐wave sleep modulation. Further characterization identified TCT as a specific diaminopimelic acid (DAP)‐containing muropeptide, GlcNAc‐(anhydro)MurNAc‐ L ‐Ala‐ D ‐Glu‐ meso DAP‐ D ‐Ala. Here, we show that the biological activity of TCT depends on Nod1, an intracellular sensor of bacterial peptidoglycan. However, Nod1‐dependent detection of TCT was found to be host specific, as human Nod1 (hNod1) poorly detected TCT, whereas mouse Nod1 (mNod1) did so efficiently. More generally, hNod1 required a tripeptide ( L ‐Ala‐ D ‐Glu‐ meso DAP) for efficient sensing of peptidoglycan, whereas mNod1 detected a tetrapeptide structure ( L ‐Ala‐ D ‐Glu‐ meso DAP‐ D ‐Ala). In murine macrophages, TCT stimulated cytokine secretion and NO production through Nod1. Finally, in vivo , injection of the tetrapeptide structure in mice triggered a transient yet strong release of cytokines into the bloodstream and the maturation of macrophages, in a Nod1‐dependent manner. This study thereby identifies Nod1 as the long sought after sensor of TCT in mammals.

Staphylococcus aureus is a major cause of community-acquired and nosocomial infections including the life-threatening conditions endocarditis, necrotizing pneumonia, necrotizing fasciitis, and septicemia. Toll-like receptor (TLR)-2, a membrane-bound microbial sensor, detects staphylococcal components, but macrophages lacking TLR2 or both TLR2 and TLR4 remain S. aureus responsive, suggesting that an alternative microbial recognition receptor might be involved. The cytoplasmic sensor nucleotide-binding oligomerization domain containing (NOD) 2/caspase recruitment domain (CARD) 15 detects muramyl dipeptide from bacterial peptidoglycans and mediates cytokine responses to S. aureus in vitro, but the physiological significance of these observations is not well defined. Here we show that NOD2-deficient mice exhibit a delayed but ultimately exacerbated ulcerative response and impaired bacterial clearance after s.c. infection with S. aureus. NOD2-dependent recognition of S. aureus and muramyl dipeptide is facilitated by α-toxin (α-hemolysin), a pore-forming toxin and virulence factor of the pathogen. The action of NOD2 is dependent on IL-1β-amplified production of IL-6, which promotes rapid bacterial killing by neutrophils. These results significantly broaden the physiological importance of NOD2 in innate immunity from the recognition of bacteria that primarily enter the cytoplasm to the detection of bacteria that typically reside extracellularly and demonstrate that this microbial sensor contributes to the discrimination between commensal bacteria and bacterial pathogens that elaborate pore-forming toxins.

The recent detection of both Nova virus (NVAV) and Bruges virus (BRGV) in European moles (Talpa europaea) in Belgium and Germany prompted a search for related hantaviruses in the Iberian mole (Talpa occidentalis). RNAlater®-preserved lung tissue from 106 Iberian moles, collected during January 2011 to June 2014 in Asturias, Spain, were analyzed for hantavirus RNA by nested/hemi-nested RT-PCR. Pairwise alignment and comparison of partial L-segment sequences, detected in 11 Iberian moles from four parishes, indicated the circulation of genetically distinct hantaviruses. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, demonstrated three distinct hantaviruses in Iberian moles: NVAV, BRGV, and a new hantavirus, designated Asturias virus (ASTV). Of the cDNA from seven infected moles processed for next generation sequencing using Illumina HiSeq1500, one produced viable contigs, spanning the S, M and L segments of ASTV. The original view that each hantavirus species is harbored by a single small-mammal host species is now known to be invalid. Host-switching or cross-species transmission events, as well as reassortment, have shaped the complex evolutionary history and phylogeography of hantaviruses such that some hantavirus species are hosted by multiple reservoir species, and conversely, some host species harbor more than one hantavirus species.

ObjectiveInflammatory bowel diseases (IBDs) are chronic relapsing remitting diseases which potentially result in hospitalisation, requiring long-term outpatient follow-up, ideally by a dedicated, multidisciplinary team. In this team, the IBD nurse is the key point of access for education, advice and support.The aim of this study was to assess the impact of introduction of an IBD nurse position on healthcare use and costs in a tertiary IBD centre.MethodsAn IBD nurse was instituted in September 2017 in our multidisciplinary IBD team. We compared differences in healthcare use 1 year before and 1 year after the introduction of an IBD nurse position for all the patients with a confirmed diagnosis of IBD attending the Robert Debre Hospital via two information sources: Programme de Médicalisation des Systèmes d’Information and Centre des Maladies Rares.Results252 patients (78.5% of patients with IBD followed up in our centre) were included in the patient education programme. After the introduction of an IBD nurse position, fewer patients were hospitalised for a flare, with less hospital stays: 56 before vs 28 after (p=0.002). An estimated saving of €35 070 was achieved through the decrease of hospitalisations for flare.More patients were also hospitalised for diagnosis: 32 hospitalisations before vs 54 hospitalisations after (p=0.001). All other hospitalisation categories were comparable, and the same reasons for hospitalisation were found before and after.ConclusionThis study demonstrates that the IBD nurse position reduces hospital admissions. Instead of the traditional model, the IBD nurse provides accessible advice and allows patients to be outpatients.