Project description:Lower urinary tract malformations are among the most common congenital anomalies in humans. The urethral plate epithelium is an endodermal signaling region that plays an essential role in external genital development; however, little is known about the molecular identity of this cell population or the genes that regulate its activity. We aim to characterize differences in gene expression between the urethral plate epithelium and surrounding mouse genital tubercles during a crucial developmental period.
Project description:Recent national surgical quality guidelines (Surgical Care Improvement Project, National Hospital Inpatient Quality Measures)state that removal of urinary catheters should occur by post-operative day two for all surgical patients. These guidelines exclude neither patients who have undergone rectal surgery nor those with epidural analgesic catheters. The common practice among most colorectal surgeons is to leave urinary catheters in for three to five days for patients who have undergone rectal operations, due to concern for urinary retention. This study aims to explore the outcomes of following the national surgical guidelines for early urinary catheter removal, especially with regards to urinary retention and urinary tract infection.
Project description:Both Aerococcus urinae (Au) and Globicatella sanguinis (Gs) colonize the human urinary tract and are in the Aerococcaceae family. These rarely pathogenic Gram-positive bacteria were identified in polymicrobial urethral catheter biofilms (CBs) using 16S rDNA and proteomic analyses in this study. For confirming the identities, Au and Gs strains were isolated from small blood agar colonies derived from the CB extracts. Longitudinal surveys of clinical urine specimens revealed their persistence in the urinary tract and recolonization of newly replaced catheters. Dominant CB cohabitating organisms were Enterobacteriaceae, especially Proteus mirabilis and Escherichia coli. The proteomes of Gs and Au profiled from the in vivo milieu suggest that their energy metabolisms rely on glycolytic, heterolactic fermentation and peptide catabolic pathways. Several PTS sugar uptake and oligopeptide ABC transport systems were also highly abundant in the in vivo proteomes of Au and Gs, indicative to adaptations to nutrients available in urine and exfoliated urothelial cells (protein and proteoglycan breakdown products). Differences in Au and Gs metabolisms pertained to citrate lyase and glycogen (only in the Gs proteome), use of Xfp to degrade D-xylulose-5’-phosphate, and synthesis pathways for enzyme cofactors pyridoxal 6’-phosphate and 4’-phosphopantothenate (the latter only in the Au proteome). Interestingly, predicted metal ion (ZnuA-like) uptake systems were abundant in Gs but not in Au in vivo. Au expressed two LPXTG-anchored surface proteins, one predicted to have a pilin D adhesion motif. We describe how two microorganisms not previously characterized metabolically adapt to the milieu in the catheterized human urinary tract. Whether they are true pathogens or bystanders in CBs needs further investigation.
Project description:Interventions: Early group: The urethral catheter is removed on postoperative day 2 or 3, before removing the epidural anesthesia catheter.
Late group: Urethral catheter removed after 2-24 hours of epidural catheter removal
Primary outcome(s): Incidence of postoperative urinary retention (POUR)
Study Design: Parallel Randomized
Project description:Proteus mirabilis is a leading cause of catheter-associated urinary tract infections (UTIs) and urolithiasis. The transcriptional regulator MrpJ inversely modulates two critical aspects of P. mirabilis UTI progression: fimbria-mediated attachment to the urinary tract, and flagella-mediated motility. Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) was used for the first time in a CAUTI pathogen to probe for in vivo direct targets of MrpJ. ChIP-seq revealed 81 78 direct MrpJ targets, including genes for motility, fimbriae and a type VI secretion system (T6SS), and the putative MrpJ binding sequence ACnCnnnnnnnGnGT.
Project description:This series of microarrays compares gene expression by the bacterial pathogen Proteus mirabilis when the transcriptional regulator mrpJ is deleted or induced to levels found during experimental urinary tract infection. The enteric bacterium Proteus mirabilis is associated with a significant number of catheter-associated urinary tract infections. Strict regulation of the antagonistic processes of adhesion and motility, mediated by fimbriae and flagella, respectively, is essential for successful disease progression. Previously, the transcriptional regulator MrpJ, which is encoded by the mrp fimbrial operon, has been shown to repress both swimming and swarming motility. Here we show that MrpJ affects a wide array of cellular processes beyond adherence and motility. Microarray analysis found that expression of mrpJ mimicking expression levels that occur during UTI leads to differential expression of 217 genes related to, among others, bacterial virulence, type VI secretion and metabolism. We probed the molecular mechanism of transcriptional regulation through MrpJ using reporter assays and chromatin immunoprecipitation (ChIP). Two virulence-associated target genes, the flagellar master regulator flhDC and mrp itself, appear to be regulated through a binding site proximal to the transcriptional start, complemented by a more distantly situated enhancer site. Furthermore, an mrpJ deletion mutant colonized the bladders of mice at significantly lower levels in a transurethral model of infection. Additionally, we observe that mrpJ is widely conserved in a collection of recent clinical isolates, leading us to conclude that our results elucidate an unanticipated role of MrpJ as a global regulator of P. mirabilis virulence. Four biological replicates were analyzed for each set of arrays (P. mirabilis HI4320 wild type vs. ΔmrpJ, and vector pLX3607 vs. mrpJ plasmid pLX3805).
Project description:Urinary tract infections (UTIs) constitute a highly relevant model of microbial adaptation, in which the contrasting effects of pathogens and commensals on host tissues are clearly displayed. While virulent Escherichia coli cause severe, potentially life-threatening disease by breaking the inertia of the mucosal barrier and infecting the kidneys, the most common outcome of bacteriuria is an asymptomatic carrier state resembling commensalism at other mucosal sites. It remains unclear if the lack of destructive inflammation merely reflects low virulence or if carrier strains actively inhibit disease associated responses in the host. To address this question, we examined the effects of asymptomatic bacterial carriage on host gene expression. Therapeutic urinary tract inoculation with the prototype ABU strain E. coli 83972 is a safe alternative approach in patients with therapy-resistant recurrent UTI. The strain establishes persistent bacteriuria, protecting patients against super-infection with more virulent strains. Using this protocol, we examined if the establishment of asymptomatic bacterial carriage alters host gene expression. After antibiotic treatment to remove prior infection, patients were inoculated with E. coli 83972 through a catheter. Blood samples were obtained before and 24 h after inoculation.
Project description:Long term-catheterization leads inevitably to a catheter-associated bacteriuria caused by multispecies bacterial biofilms growing on and in the catheters. The overall goal of the presented study was (I) to unravel bacterial community structure and function of such an uropathogenic biofilm and (II) to elucidate the interplay between bacterial virulence and the human immune system within the urine. To this end, a metaproteomics approach combined with in vitro proteomics analyses was employed to investigate both, the pro- and eukaryotic protein inventory. Our proteome analyses demonstrated that the biofilm of the investigated catheter is dominated by three bacterial species, i.e. Pseudomonas aeruginosa, Morganella morganii and Bacteroides sp., and identified iron limitation as one of the major challenges in the bladder environment. In vitro proteome analysis of P. aeruginosa and M. morganii isolated from the biofilm revealed that those opportunistic pathogens are able to overcome iron restriction via the production of siderophores and high expression of corresponding receptors. Notably, a comparison of in vivo and in vitro protein profiles of P. aeruginosa and M. morganii also indicated that the bacteria employ different strategies to adapt to the urinary tract. Whilst P. aeruginosa seems to express secreted and surface-exposed proteases to escape the human innate immune system and metabolizes amino acids, M. morganii is able to take up sugars and to degrade urea. Most interestingly, a comparison of urine protein profiles of three long-term catheterized patients and three healthy control persons demonstrated the elevated level of proteins associated to neutrophils, macrophages and complement system in the patient urine, which might point to a specific activation of the innate immune system in response to biofilm-associated urinary tract infections. We thus hypothesize that the often asymptomatic nature of CAUTI´s might be based on a fine-tuned balance between the expression of bacterial virulence factors and the human immune system. Long term-catheterization leads inevitably to a catheter-associated bacteriuria caused by multispecies bacterial biofilms growing on and in the catheters. The overall goal of the presented study was (I) to unravel bacterial community structure and function of such an uropathogenic biofilm and (II) to elucidate the interplay between bacterial virulence and the human immune system within the urine. To this end, a metaproteomics approach combined with in vitro proteomics analyses was employed to investigate both, the pro- and eukaryotic protein inventory. Our proteome analyses demonstrated that the biofilm of the investigated catheter is dominated by three bacterial species, i.e. Pseudomonas aeruginosa, Morganella morganii and Bacteroides sp., and identified iron limitation as one of the major challenges in the bladder environment. In vitro proteome analysis of P. aeruginosa and M. morganii isolated from the biofilm revealed that those opportunistic pathogens are able to overcome iron restriction via the production of siderophores and high expression of corresponding receptors. Notably, a comparison of in vivo and in vitro protein profiles of P. aeruginosa and M. morganii also indicated that the bacteria employ different strategies to adapt to the urinary tract. Whilst P. aeruginosa seems to express secreted and surface-exposed proteases to escape the human innate immune system and metabolizes amino acids, M. morganii is able to take up sugars and to degrade urea. Most interestingly, a comparison of urine protein profiles of three long-term catheterized patients and three healthy control persons demonstrated the elevated level of proteins associated to neutrophils, macrophages and complement system in the patient urine, which might point to a specific activation of the innate immune system in response to biofilm-associated urinary tract infections. We thus hypothesize that the often asymptomatic nature of CAUTI´s might be based on a fine-tuned balance between the expression of bacterial virulence factors and the human immune system.
Project description:RIVUR Trial participants had Agilent 1M probe and or Nimblegen 2.1M probe aCGH performed on genomic DNA. The study was designed to discover DNA copy number variations in genes critical in kidney/urinary tract development and urinary tract infection susceptibility. Reference DNA used is a single male sample
Project description:The analysis of catheter biofilms (CBs) from patients with neurogenic bladder disorders revealed persistent colonization by polymicrobial communities. The recurrence of bacterial species in the CBs of sequentially replaced catheters suggests urothelial reservoirs responsible for recolonization of the catheter surface. Proteomic data for CB samples were indicative of chronic inflammation in the patients’ urinary tracts via neutrophil and eosinophil infiltration and epithelial cell exfoliation. These host defense pathways, effective in killing pathogens during uncomplicated urinary tract infection, failed to eliminate CBs. Intermittent antibiotic drug treatment had different outcomes: either replacement of drug-susceptible by drug-tolerant bacteria or transient microbial biomass reduction followed by resurgence of the previously colonizing bacteria. Proteins that sequester iron and zinc such as lactotransferrin, lipocalin-2 and calprotectin were abundant in the patient’s CBs and urine sediments. Indicative of a host-pathogen battle for bivalent metal ions, acquisition and transport systems for such ions were highly expressed by many organisms residing in CBs. Species part of the Enterococcaceae and Aerococcaceae families, generally not well-characterized in their ability to synthesize siderophores, frequently cohabitated biofilms dominated by siderophore-producing Enterobacteriaceae. In support of metal acquisition cooperativity, we noticed positive abundance correlations for a Proteus mirabilis yersiniabactin-type siderophore system and two Enterococcus faecalis ABC transporters. Distinct bacterial strains highly expressed known or putative cytotoxins that appeared to compromise the survival of co-resident bacteria, e.g. a P. mirabilis hemolysin and Pseudomonas aeruginosa type 6 secretion and pyoverdin biosynthesis systems. In conclusion, there is support for cooperative and competitive behaviors among bacteria cohabitating CBs.