Denture-related stomatitis, which has been described clinically in the literature, is either localized or generalized inflammation of the oral mucosa in connection with a removable prosthesis. During this inflammatory process, the mycobacterial biofilm and the host's immune response play an essential role. Among microorganisms of this mixed biofilm, the species proliferates easily and changes from a commensal to an opportunistic pathogen.
View Article and Find Full Text PDFMany studies show that the human microbiome plays a critical role in the chronic pathologies of obesity, inflammatory bowel diseases, and diabetes. More recently, the interaction between cancer and the microbiome has been highlighted. Most studies have focused on the gut microbiota because it represents the most extensive bacterial community, and the body of evidence correlating it with gut syndromes is increasing.
View Article and Find Full Text PDFBackground: Bacteremia, or bloodstream infection (BSI), is a leading cause of death among patients with certain types of cancer. A previous study reported that intestinal domination, defined as occupation of at least 30 % of the microbiota by a single bacterial taxon, is associated with BSI in patients undergoing allo-HSCT. However, the impact of the intestinal microbiome before treatment initiation on the risk of subsequent BSI remains unclear.
View Article and Find Full Text PDFGastrointestinal disturbances are a side-effect frequently associated with haematological malignancies due to the intensive cytotoxic treatment given in connection with bone marrow transplantation (BMT). However, intestinal microbiota changes during chemotherapy remain poorly described, probably due to the use of culture-based and low-resolution molecular methods in previous studies. The objective of our study was to apply a next generation DNA sequencing technology to analyse chemotherapy-induced changes in faecal microbiota.
View Article and Find Full Text PDFTuberculosis (TB) is responsible for a high mortality rate (2.5%) worldwide, mainly in developing countries with a high prevalence of human immunodeficiency virus (HIV). The emergence of multiresistant strains of TB poses an extreme risk for TB outbreaks and highlights the need for global TB control strategies.
View Article and Find Full Text PDFSpondylarthritis is still viewed as a reaction to infectious agents, as opposed to an infection by persistent bacteria, for several reasons: (a) an infection is considered proven only when the organism can be cultured; (b) no studies have identified dormant bacteria in the tissues targeted by spondylarthritis; (c) the bacterial persistence hypothesis has no therapeutic implications at the time being, since antibiotics are effective neither on dormant bacteria nor on the manifestations of spondylarthritis; and (d) the high prevalence of borderline disorders combining features of spondylarthritis and of psoriatic arthritis, or even rheumatoid arthritis (RA), would indicate a role for dormant bacteria in these last two diseases. However, recent data on dormant bacteria have rekindled interest in the bacterial persistence hypothesis. Dormant bacteria cannot be cultured, because they express only a small group of genes, known as the regulon, which includes genes for transcription factors that block the expression of the usual bacterial genes.
View Article and Find Full Text PDFThroughout the human lifetime, the intestinal microbiota performs vital functions, such as barrier function, metabolic reactions, trophic effects, and maturation of the host's innate and adaptive immune responses. Development of the intestinal microbiota in infants is characterized by rapid and large changes in microbial abundance, diversity, and composition. These changes are influenced by medical, cultural, and environmental factors such as mode of delivery, diet, familial environment, diseases, and therapies used.
View Article and Find Full Text PDFThe diffusion of antibiotics in endocarditis vegetation bacterial masses has not been described, although it may influence the efficacy of antibiotic therapy in endocarditis. The objective of this work was to assess the diffusion of ofloxacin in experimental endocarditis vegetation bacterial masses using synchrotron-radiation UV fluorescence microspectroscopy. Streptococcal endocarditis was induced in 5 rabbits.
View Article and Find Full Text PDFBackground: Fecal calprotectin has been proposed as a non-invasive marker of intestinal inflammation in inflammatory bowel disease in adults and children. Fecal calprotectin levels have been reported to be much higher in both healthy full-term and preterm infants than in children and adults.
Objective: To determine the time course of fecal calprotectin (f-calprotectin) excretion in preterm infants from birth until hospital discharge and to identify factors influencing f-calprotectin levels in the first weeks of life, including bacterial establishment in the gut.
Modifications in microbial colonization of the human gut are believed to affect intestinal homeostasis and increase the risk of gastrointestinal diseases. The present study examined different methods for investigating the dynamic characterization of the intestinal microbiota in preterm infants. Fecal samples were collected weekly from ten preterm infants during their stay in a neonatal intensive care unit.
View Article and Find Full Text PDFAntibiotic-associated diarrhea (AAD) is associated with altered intestinal microflora and other symptoms that may lead to possibly death. In critically ill patients, diarrhea increases rates of morbimortality. Assessing diarrhea risks is thus important for clinicians.
View Article and Find Full Text PDFAims: Neonatal microbiota development seems to play a key role in the early origins of health and disease. However, the analysis of this complex ecosystem is still difficult. The aim of this work was to investigate the feasibility of a new technique, denaturing high-performance liquid chromatography (dHPLC), to analyze newborn intestinal microbiota using genomic approaches.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
April 2008
A method was developed by using gas chromatography-mass spectrometry in the electron impact ionization mode to quantify citrulline in plasma, red blood cells (RBC) and urine. For all three fluids, citrulline was extracted on ion exchange resins, before derivatization to its propyl-heptaflorobutyryl-ester. Assay precision (coefficient of variation, CV) was <5%, recovery% was >90% and the within- and between-day CV were <10% on 200 microL of plasma and RBC, and 400 microL of urine.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
November 2007
To determine whether circulating citrulline can be manipulated in vivo in humans, and, if so, whether citrulline availability affects the levels of related amino acids, nitric oxide, urinary citrulline, and urea nitrogen, 10 healthy volunteers were studied on 3 separate days: 1) under baseline conditions; 2) after a 24-h treatment with phenylbutyrate (0.36 g.kg(-1).
View Article and Find Full Text PDFThe mucosa-associated microbiota lining the gut epithelium might play a central role in the activation and/or perpetuation of mucosal inflammation in Crohn's disease (CD). We sought for localized dysbiosis by comparing the biodiversity and composition of the microbiotas in ulcerated and nonulcerated mucosal samples from patients with CD. Biopsy samples (n = 75) of ulcerated and adjacent nonulcerated mucosa were collected during colonoscopy from 15 patients, from the ileum, right colon, left colon, and rectum.
View Article and Find Full Text PDFBackground: The mucosa-associated microbiota, being very close to the inflammatory process associated with inflammatory bowel disease (IBD), may have a pathogenic role. We used a culture-independent method to analyze the mucosa-associated microbiota in IBD patients at various points of the distal digestive tract.
Methods: Thirty-five patients (20 with Crohn's disease, 11 with ulcerative colitis, and 4 controls) underwent colonoscopy.
Necrotizing enterocolitis (NEC) is among the most severe conditions that can affect preterm infants. Although the etiology of NEC remains unknown, initial bacterial colonization could play a pivotal role in the development of NEC. To further explore the putative relationship between pathogen microorganisms and NEC, we conducted a prospective case-control study in 12 preterm infants with a new approach based on molecular techniques.
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