Salmonella re-engineers the intestinal environment to break colonization resistance in the presence of a compositionally intact microbiota.

The gut microbiota prevents harmful microbes from entering the body, a function known as colonization resistance. The enteric pathogen Salmonella enterica serovar (S.) Typhimurium uses its virulence factors to break colonization resistance through unknown mechanisms.

Gut epithelial electrical cues drive differential localization of enterobacteria.

Salmonella translocate to the gut epithelium via microfold cells lining the follicle-associated epithelium (FAE). How Salmonella localize to the FAE is not well characterized. Here we use live imaging and competitive assays between wild-type and chemotaxis-deficient mutants to show that Salmonella enterica serotype Typhimurium (S.

The Relationship between Microbial Communities in Coffee Fermentation and Aroma with Metabolite Attributes of Finished Products.

Coffee is a critical agricultural commodity and is used to produce premium beverages enjoyed by people worldwide. The microbiome of coffee beans has proven to be an essential tool that improves the flavor profile of coffee by creating aromatic flavor compounds through natural fermentation. This study investigated the natural microbial consortium during the wet process fermentation of coffee onsite in Thailand in order to identify the correlation between microbial diversity and biochemical characteristics including flavor, aroma, and metabolic attributes.

The IRE1α-XBP1 Signaling Axis Promotes Glycolytic Reprogramming in Response to Inflammatory Stimuli.

Immune cells must be able to adjust their metabolic programs to effectively carry out their effector functions. Here, we show that the endoplasmic reticulum (ER) stress sensor Inositol-requiring enzyme 1 alpha (IRE1α) and its downstream transcription factor X box binding protein 1 (XBP1) enhance the upregulation of glycolysis in classically activated macrophages (CAMs). The IRE1α-XBP1 signaling axis supports this glycolytic switch in macrophages when activated by lipopolysaccharide (LPS) stimulation or infection with the intracellular bacterial pathogen Brucella abortus.

Development of Bioactive Edible Films Containing Probiotics as a Coating for Fresh-Cut Fruit.

Bioactive edible films have received more attention in recent years as a method for food preservation with value-added functions. The aim of this study was to develop a bioactive edible film containing mucilage of cactus () and incorporating the probiotic strain FM11-2 as an active component to promote consumer health benefits. is rich in nutritional and bioactive compounds and the abundance of this cactus makes it attractive for food applications.

The Vi Capsular Polysaccharide of Salmonella Typhi Promotes Macrophage Phagocytosis by Binding the Human C-Type Lectin DC-SIGN.

Capsular polysaccharides are common virulence factors of extracellular, but not intracellular bacterial pathogens, due to the antiphagocytic properties of these surface structures. It is therefore paradoxical that Salmonella enterica subspecies serovar Typhi, an intracellular pathogen, synthesizes a virulence-associated (Vi) capsule, which exhibits antiphagocytic properties. Here, we show that the Vi capsular polysaccharide has different functions when S.

Active Thermoplastic Starch Film with Watermelon Rind Extract for Future Biodegradable Food Packaging.

Petrochemical plastic wastes generate serious environmental problems because they are resistant to natural decomposition. The aim of this study was to develop a biodegradable active thermoplastic film composed of polyvinyl alcohol (PVA), corn starch (ST), glycerol, and the active compounds from watermelon rind extract (WMRE), or PVA/ST/WMRE, using the casting technique. The film was examined for its mechanical, antioxidant, and functional properties against selected foodborne pathogens.

Tumor Necrosis Factor Alpha Contributes to Inflammatory Pathology in the Placenta during Brucella abortus Infection.

Research on Brucella pathogenesis has focused primarily on its ability to cause persistent intracellular infection of the mononuclear phagocyte system. At these sites, Brucella abortus evades innate immunity, which results in low-level inflammation and chronic infection of phagocytes. In contrast, the host response in the placenta during infection is characterized by severe inflammation and extensive extracellular replication of B.

A preclinical hybrid curriculum and its impact on dental student learning outcomes.

Objectives: The purpose of this study is to measure how the implementation of an online, preclinical hybrid curriculum impacts dental student clinic readiness, the outcomes of grades, critical thinking skills, and student and faculty perceptions respectively.

Methods: This longitudinal comparative and descriptive study used objective data and subjective (survey) data for 4 dental class cohorts. Groups A and B experienced a traditional lecture-based curriculum, while Groups C and D experienced a hybrid curriculum that was lecture-free and implemented active learning.

Helping may be Harming: unintended negative consequences of providing social support.

While social support is generally considered a helpful resource for employees, it can also serve as a job stressor. Unhelpful workplace social support (UWSS) is any action taken by a supervisor and/or colleague that the recipient believes was intended to benefit him or her but is perceived as unhelpful or harmful. Two studies, one qualitative and one quantitative, identified types of UWSS and demonstrated that unhelpful support can operate as a job stressor in relating to strains.

High-Fat Diet and Antibiotics Cooperatively Impair Mitochondrial Bioenergetics to Trigger Dysbiosis that Exacerbates Pre-inflammatory Bowel Disease.

The clinical spectra of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) intersect to form a scantily defined overlap syndrome, termed pre-IBD. We show that increased Enterobacteriaceae and reduced Clostridia abundance distinguish the fecal microbiota of pre-IBD patients from IBS patients. A history of antibiotics in individuals consuming a high-fat diet was associated with the greatest risk for pre-IBD.

Brucella abortus Infection of Placental Trophoblasts Triggers Endoplasmic Reticulum Stress-Mediated Cell Death and Fetal Loss via Type IV Secretion System-Dependent Activation of CHOP.

Subversion of endoplasmic reticulum (ER) function is a feature shared by multiple intracellular bacteria and viruses, and in many cases this disruption of cellular function activates pathways of the unfolded protein response (UPR). In the case of infection with , the etiologic agent of brucellosis, the unfolded protein response in the infected placenta contributes to placentitis and abortion, leading to pathogen transmission. Here we show that infection of pregnant mice led to death of infected placental trophoblasts in a manner that depended on the VirB type IV secretion system (T4SS) and its effector VceC.

Utilization of Host Polyamines in Alternatively Activated Macrophages Promotes Chronic Infection by Brucella abortus.

Treatment of intracellular bacterial pathogens with antibiotic therapy often requires a long course of multiple drugs. A barrier to developing strategies that enhance antibiotic efficacy against these pathogens is our poor understanding of the intracellular nutritional environment that maintains bacterial persistence. The intracellular pathogen survives and replicates preferentially in alternatively activated macrophages (AAMs); however, knowledge of the metabolic adaptations promoting exploitation of this niche is limited.

NOD1 and NOD2 signalling links ER stress with inflammation.

Endoplasmic reticulum (ER) stress is a major contributor to inflammatory diseases, such as Crohn disease and type 2 diabetes. ER stress induces the unfolded protein response, which involves activation of three transmembrane receptors, ATF6, PERK and IRE1α. Once activated, IRE1α recruits TRAF2 to the ER membrane to initiate inflammatory responses via the NF-κB pathway.

Phospholipase A1 modulates the cell envelope phospholipid content of Brucella melitensis, contributing to polymyxin resistance and pathogenicity.

A subset of bacterial pathogens, including the zoonotic Brucella species, are highly resistant against polymyxin antibiotics. Bacterial polymyxin resistance has been attributed primarily to the modification of lipopolysaccharide; however, it is unknown what additional mechanisms mediate high-level resistance against this class of drugs. This work identified a role for the Brucella melitensis gene bveA (BMEII0681), encoding a predicted esterase, in the resistance of B.

Alteration of NCoR corepressor splicing in mice causes increased body weight and hepatosteatosis without glucose intolerance.

Alternative mRNA splicing is an important means of diversifying function in higher eukaryotes. Notably, both NCoR and SMRT corepressors are subject to alternative mRNA splicing, yielding a series of distinct corepressor variants with highly divergent functions. Normal adipogenesis is associated with a switch in corepressor splicing from NCoRω to NCoRδ, which appears to help regulate this differentiation process.

A protein-conjugate approach to develop a monoclonal antibody-based antigen detection test for the diagnosis of human brucellosis.

Human brucellosis is most commonly diagnosed by serology based on agglutination of fixed Brucella abortus as antigen. Nucleic acid amplification techniques have not proven capable of reproducibly and sensitively demonstrating the presence of Brucella DNA in clinical specimens. We sought to optimize a monoclonal antibody-based assay to detect Brucella melitensis lipopolysaccharide in blood by conjugating B.

The ability of thyroid hormone receptors to sense t4 as an agonist depends on receptor isoform and on cellular cofactors.

T4 (3,5,3',5'-tetraiodo-l-thyronine) is classically viewed as a prohormone that must be converted to the T3 (3,5,3'-triiodo-l-thyronine) form for biological activity. We first determined that the ability of reporter genes to respond to T4 and to T3 differed for the different thyroid hormone receptor (TR) isoforms, with TRα1 generally more responsive to T4 than was TRβ1. The response to T4 vs T3 also differed dramatically in different cell types in a manner that could not be attributed to differences in deiodinase activity or in hormone affinity, leading us to examine the role of TR coregulators in this phenomenon.

A mechanism for pituitary-resistance to thyroid hormone (PRTH) syndrome: a loss in cooperative coactivator contacts by thyroid hormone receptor (TR)beta2.

Thyroid hormone receptors (TR) are hormone-modulated transcription factors that regulate overall metabolic rate, lipid utilization, heart rate, and development. TR are expressed as a mix of interrelated receptor isoforms. The TRβ2 isoform is expressed in the hypothalamus and pituitary, where it plays an important role in the feedback regulation of thyroid hormone levels.

The p160 coactivator PAS-B motif stabilizes nuclear receptor binding and contributes to isoform-specific regulation by thyroid hormone receptors.

Thyroid hormone receptors (TRs) are hormone-regulated transcription factors that play multiple roles in vertebrate endocrinology and development. TRs are expressed as a series of distinct receptor isoforms that mediate different biological functions. The TRbeta2 isoform is expressed primarily in the hypothalamus, pituitary, cochlea, and retina, and displays an enhanced response to hormone agonist relative to the other TR isoforms.

Construction of a reporter system to study Burkholderia mallei type III secretion and identification of the BopA effector protein function in intracellular survival.

Burkholderia mallei, the aetiological agent of glanders disease, is a Gram-negative facultative intracellular bacterium. Despite numerous studies, the detailed mechanism of its pathogenesis is almost unknown. The presence of a type III secretion system (TTSS) is one of the known mechanisms associated with virulence.

Effect of flagellar mutations on Yersinia enterocolitica biofilm formation.

Yersinia enterocolitica biovar 1B is one of a number of strains pathogenic to humans in the genus Yersinia. It has three different type III secretion systems, Ysc, Ysa, and the flagella. In this study, the effect of flagella on biofilm formation was evaluated.

The structure of xylem vessels in grapevine (Vitaceae) and a possible passive mechanism for the systemic spread of bacterial disease.

Xylem-dwelling pathogens become systemic, suggesting that microorganisms move efficiently in the xylem. To better understand xylem pathways and how bacteria move within the xylem, vessel connectivity between stems and leaves of Vitis vinifera cv. Chardonnay and Muscadinia rotundifolia cv.

YmoA negatively regulates expression of invasin from Yersinia enterocolitica.

inv encodes invasin, which is the primary invasion factor of Yersinia enterocolitica. inv expression in vitro is regulated in response to temperature, pH, and growth phase. In vitro, inv is maximally expressed at 26 degrees C and repressed at 37 degrees C at neutral pH but, when the pH of the media is adjusted to 5.