456 results on '"Enteric pathogen"'
Search Results
52. Construction of a Dose–Illness Relationship via Modeling Morbidity and Application to Risk Assessment of Wastewater Reuse.
- Author
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Gao, Tingting, Chen, Rong, Liu, Yanzheng, Wang, Xiaochang C., and Li, Yuyou
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PATHOGENIC microorganisms ,WASTEWATER treatment ,WATER reuse ,DISEASES ,ENTEROVIRUSES ,STANDARDS - Abstract
Abstract: A disease burden (DB) evaluation for environmental pathogens is generally performed using disability‐adjusted life years with the aim of providing a quantitative assessment of the health hazard caused by pathogens. A critical step in the preparation for this evaluation is the estimation of morbidity between exposure and disease occurrence. In this study, the method of a traditional dose–response analysis was first reviewed, and then a combination of the theoretical basis of a “single‐hit” and an “infection‐illness” model was performed by incorporating two critical factors: the “infective coefficient” and “infection duration.” This allowed a dose–morbidity model to be built for direct use in DB calculations. In addition, human experimental data for typical intestinal pathogens were obtained for model validation, and the results indicated that the model was well fitted and could be further used for morbidity estimation. On this basis, a real case of a water reuse project was selected for model application, and the morbidity as well as the DB caused by intestinal pathogens during water reuse was evaluated. The results show that the DB attributed to Enteroviruses was significant, while that for enteric bacteria was negligible. Therefore, water treatment technology should be further improved to reduce the exposure risk of Enteroviruses. Since road flushing was identified as the major exposure route, human contact with reclaimed water through this pathway should be limited. The methodology proposed for model construction not only makes up for missing data of morbidity during risk evaluation, but is also necessary to quantify the maximum possible DB. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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53. Risk factors for sporadic Giardia infection in the USA: a case-control study in Colorado and Minnesota.
- Author
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Reses, H. E., Gargano, J. W., Liang, J. L., Cronquist, A., Smith, K., Collier, S. A., Roy, S. L., Vanden Eng, J., Bogard, A., Lee, B., Hlavsa, M. C., Rosenberg, E. S., Fullerton, K. E., Beach, M. J., and Yoder, J. S.
- Abstract
Giardia duodenalis is the most common intestinal parasite of humans in the USA, but the risk factors for sporadic (non-outbreak) giardiasis are not well described. The Centers for Disease Control and Prevention and the Colorado and Minnesota public health departments conducted a case-control study to assess risk factors for sporadic giardiasis in the USA. Cases (N = 199) were patients with non-outbreak-associated laboratory-confirmed Giardia infection in Colorado and Minnesota, and controls (N = 381) were matched by age and site. Identified risk factors included international travel (aOR = 13.9; 95% CI 4.9-39.8), drinking water from a river, lake, stream, or spring (aOR = 6.5; 95% CI 2.0-20.6), swimming in a natural body of water (aOR = 3.3; 95% CI 1.5-7.0), male-male sexual behaviour (aOR = 45.7; 95% CI 5.8-362.0), having contact with children in diapers (aOR = 1.6; 95% CI 1.01-2.6), taking antibiotics (aOR = 2.5; 95% CI 1.2-5.0) and having a chronic gastrointestinal condition (aOR = 1.8; 95% CI 1.1-3.0). Eating raw produce was inversely associated with infection (aOR = 0.2; 95% CI 0.1-0.7). Our results highlight the diversity of risk factors for sporadic giardiasis and the importance of non-international-travel-associated risk factors, particularly those involving person-to-person transmission. Prevention measures should focus on reducing risks associated with diaper handling, sexual contact, swimming in untreated water, and drinking untreated water. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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54. A Role for Salivary Peptides in the Innate Defense Against Enterotoxigenic Escherichia coli.
- Author
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Brown, Jeffrey W., Badahdah, Arwa, Iticovici, Micah, Vickers, Tim J., Alvarado, David M., Helmerhorst, Eva J., Oppenheim, Frank G., Mills, Jason C., Ciorba, Matthew A., Fleckenstein, James M., and Bullitt, Esther
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PEPTIDES , *ESCHERICHIA coli , *DIARRHEA , *ANTI-infective agents , *OROPHARYNX - Abstract
Background: Diarrheal disease from enterotoxigenic Escherichia coli (ETEC) causes significant worldwide morbidity and mortality in young children residing in endemic countries and is the leading cause of traveler's diarrhea. As ETEC enters the body through the oral cavity and cotransits the digestive tract with salivary components, we hypothesized that the antimicrobial activity of salivary proteins might extend beyond the oropharynx into the proximal digestive tract.Results: Here, we show that the salivary peptide histatin-5 binds colonization factor antigen I pili, thereby blocking adhesion of ETEC to intestinal epithelial cells. Mechanistically, we demonstrate that histatin-5 stiffens the typically dynamic pili, abolishing their ability to function as spring-like shock absorbers, thereby inhibiting colonization within the turbulent vortices of chyme in the gastrointestinal tract.Conclusions: Our data represent the first report of a salivary component exerting specific antimicrobial activity against an enteric pathogen and suggest that histatin-5 and related peptides might be exploited for prophylactic and/or therapeutic uses. Numerous viruses, bacteria, and fungi traverse the oropharynx to cause disease, so there is considerable opportunity for various salivary components to neutralize these pathogens prior to arrival at their target organ. Identification of additional salivary components with unexpectedly broad antimicrobial spectra should be a priority. [ABSTRACT FROM AUTHOR]- Published
- 2018
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55. Giardia secretome highlights secreted tenascins as a key component of pathogenesis.
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CATHEPSIN B , *GIARDIA , *CYSTEINE proteinases , *MEMBRANE proteins , *PROTEIN expression - Abstract
Background: Giardia is a protozoan parasite of public health relevance that causes gastroenteritis in a wide range of hosts. Two genetically distinct lineages (assemblages A and B) are responsible for the human disease. Although it is clear that differences in virulence occur, the pathogenesis and virulence of Giardia remain poorly understood. Results: The genome of Giardia is believed to contain open reading frames that could encode as many as 6000 proteins. By successfully applying quantitative proteomic analyses to the whole parasite and to the supernatants derived from parasite culture of assemblages A and B, we confirm expression of ∼1600 proteins from each assemblage, the vast majority of which are common to both lineages. To look for signature enrichment of secreted proteins, we considered the ratio of proteins in the supernatant compared with the pellet, which defined a small group of enriched proteins, putatively secreted at a steady state by cultured growing trophozoites of both assemblages. This secretome is enriched with proteins annotated to have N-terminal signal peptide. The most abundant secreted proteins include known virulence factors such as cathepsin B cysteine proteases and members of a Giardia superfamily of cysteine-rich proteins that comprise variant surface proteins, high-cysteine membrane proteins, and a new class of virulence factors, the Giardia tenascins. We demonstrate that physiological function of human enteric epithelial cells is disrupted by such soluble factors even in the absence of the trophozoites. Conclusions: We are able to propose a straightforward model of Giardia pathogenesis incorporating key roles for the major Giardia-derived soluble mediators. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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56. Disruption of the Gut Ecosystem by Antibiotics.
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Mi Young Yoon and Sang Sun Yoon
- Abstract
The intestinal microbiota is a complex ecosystem consisting of various microorganisms that expands human genetic repertoire and therefore affects human health and disease. The metabolic processes and signal transduction pathways of the host and intestinal microorganisms are intimately linked, and abnormal progression of each process leads to changes in the intestinal environment. Alterations in microbial communities lead to changes in functional structures based on the metabolites produced in the gut, and these environmental changes result in various bacterial infections and chronic enteric inflammatory diseases. Here, we illustrate how antibiotics are associated with an increased risk of antibiotic-associated diseases by driving intestinal environment changes that favor the proliferation and virulence of pathogens. Understanding the pathogenesis caused by antibiotics would be a crucial key to the treatment of antibiotic-associated diseases by mitigating changes in the intestinal environment and restoring it to its original state. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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57. Infectious Diarrhea
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Beheshti, Manie, George, W. Lance, Norman, Dean, editor, and Yoshikawa, Thomas, editor
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- 2009
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58. Campylobacter Infections
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Allos, Ban Mishu, Brachman, Philip S., editor, and Abrutyn, Elias, editor
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- 2009
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59. Antimicrobial Resistance among Enteric Pathogens
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Pickering, Larry K., Finn, Adam, editor, and Pollard, Andrew J., editor
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- 2008
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60. Selected commensals educate the intestinal vascular and immune system for immunocompetence
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Romero, R., Zarzycka, A., Preussner, M., Fischer, Florence, Hain, T., Herrmann, J.-P., Roth, K., Keber, C.U., Suryamohan, K., Raifer, H., Luu, M., Leister, H., Bertrams, W., Klein, M., Shams-Eldin, H., Jacob, R., Mollenkopf, H.-J., Rajalingam, K., Visekruna, A., Steinhoff, U., Romero, R., Zarzycka, A., Preussner, M., Fischer, Florence, Hain, T., Herrmann, J.-P., Roth, K., Keber, C.U., Suryamohan, K., Raifer, H., Luu, M., Leister, H., Bertrams, W., Klein, M., Shams-Eldin, H., Jacob, R., Mollenkopf, H.-J., Rajalingam, K., Visekruna, A., and Steinhoff, U.
- Abstract
Background The intestinal microbiota fundamentally guides the development of a normal intestinal physiology, the education, and functioning of the mucosal immune system. The Citrobacter rodentium-carrier model in germ-free (GF) mice is suitable to study the influence of selected microbes on an otherwise blunted immune response in the absence of intestinal commensals. Results Here, we describe that colonization of adult carrier mice with 14 selected commensal microbes (OMM12 + MC2) was sufficient to reestablish the host immune response to enteric pathogens; this conversion was facilitated by maturation and activation of the intestinal blood vessel system and the step- and timewise stimulation of innate and adaptive immunity. While the immature colon of C. rodentium-infected GF mice did not allow sufficient extravasation of neutrophils into the gut lumen, colonization with OMM12 + MC2 commensals initiated the expansion and activation of the visceral vascular system enabling granulocyte transmigration into the gut lumen for effective pathogen elimination. Conclusions Consortium modeling revealed that the addition of two facultative anaerobes to the OMM12 community was essential to further progress the intestinal development. Moreover, this study demonstrates the therapeutic value of a defined consortium to promote intestinal maturation and immunity even in adult organisms.
- Published
- 2022
61. Alternatives to Antimicrobials
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Poole, Toni L., Callaway, Todd R., Nisbet, David J., Georgiev, Vassil St., editor, and Simjee, Shabbir, editor
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- 2007
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62. Gastrointestinal Infections in the Immunocompromised Host
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Georgiev, Vassil St. and Georgiev, Vassil St., editor
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- 2003
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63. Sources of Enteric Disease in Canada
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Guan, Tiffany T. Y., Holley, Richard A., Guan, Tiffany T. Y., and Holley, Richard A.
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- 2003
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64. An Oral Vaccine in Maize Protects Against Transmissible Gastroenteritis Virus in Swine
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Jilka, J., Erickson, L., editor, Yu, W.-J., editor, Brandle, J., editor, and Rymerson, R., editor
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- 2002
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65. Single-stage decompression of C1–D9 anterior epidural abscess by a gas-producing enteric pathogen
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Vetri Nallathambi and M Atharsh Chander
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Orthopedic surgery ,medicine.medical_specialty ,Epidural abscess ,Decompression ,business.industry ,Single stage ,epidural abscess ,Enteric pathogen ,medicine.disease ,Surgery ,Sepsis ,medicine ,Orthopedics and Sports Medicine ,Neurology (clinical) ,Presentation (obstetrics) ,escherichia coli ,Abscess ,business ,epidural abscess with gas ,Neurological impairment ,RD701-811 ,cervicothoracic epidural abscess ,e. coli epidural abscess - Abstract
Multilevel pyogenic spinal epidural abscess is a rare presentation, and there are only a few documented cases. This is a case report of a cervicothoracic epidural abscess (C1–D9) presenting with sepsis and neurological impairment due to a gas-producing enteric organism that was managed by surgical decompression. The abscess was drained in a single-stage multilevel procedure. The patient recovered gradually in the postoperative period clinically and neurologically and is on follow-up for two years. The peculiarity of this case is the absence of any vertebral or disc involvement in the presence of such an extensive anterior epidural abscess.
- Published
- 2021
66. CqsA/LuxS-HapR Quorum sensing circuit modulates type VI secretion system VflT6SS2 in Vibrio fluvialis
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He Gao, Anran Zhang, Yu Han, Xiaoshu Liu, Ping Liu, Biao Kan, Jingjing Pan, Weili Liang, and Yuanming Huang
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0301 basic medicine ,Epidemiology ,030106 microbiology ,Immunology ,General Medicine ,Enteric pathogen ,Biology ,biology.organism_classification ,Microbiology ,03 medical and health sciences ,Quorum sensing ,030104 developmental biology ,Infectious Diseases ,Vibrio fluvialis ,Virology ,Drug Discovery ,Parasitology ,Secretion ,Type VI secretion system - Abstract
Vibrio fluvialis is an emerging enteric pathogen of increasing public health threat. Two quorum sensing (QS) systems, VfqI-VfqR and CqsA/LuxS-HapR, and two type VI secretion systems (T6SSs), VflT6S...
- Published
- 2021
67. Porcine rotavirus B as primary causative agent of diarrhea outbreaks in newborn piglets
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Admilton Gonçalves de Oliveira, Thalita Evani Silva de Oliveira, Flavia Megumi Miyabe, Selwyn Arlington Headley, Thiago Fernandes, Amauri Alcindo Alfieri, Alais Maria Dall Agnol, Alice Fernandes Alfieri, and Raquel Arruda Leme
- Subjects
Rotavirus ,Diarrhea ,0301 basic medicine ,Molecular biology ,Swine ,040301 veterinary sciences ,Science ,Enteric pathogen ,Biology ,medicine.disease_cause ,Microbiology ,Article ,Rotavirus Infections ,Disease Outbreaks ,0403 veterinary science ,Viral Proteins ,03 medical and health sciences ,Virology ,Genotype ,medicine ,Animals ,Phylogeny ,Swine Diseases ,Multidisciplinary ,Base Sequence ,Porcine rotavirus ,Outbreak ,04 agricultural and veterinary sciences ,030104 developmental biology ,Animals, Newborn ,Herd ,Medicine ,medicine.symptom ,Vp7 gene - Abstract
Rotavirus (RV) is considered a major cause of acute viral gastroenteritis in young animals. RV is classified into nine species, five of which have been identified in pigs. Most studies worldwide have highlighted diarrhoea outbreaks caused by RVA, which is considered the most important RV species. In the present study, we described the detection and characterization of porcine RVB as a primary causative agent of diarrhoea outbreaks in pig herds in Brazil. The study showed a high frequency (64/90; 71.1%) of RVB diagnosis in newborn piglets associated with marked histopathological lesions in the small intestines. Phylogenetic analysis of the VP7 gene of wild-type RVB strains revealed a high diversity of G genotypes circulating in one geographic region of Brazil. Our findings suggest that RVB may be considered an important primary enteric pathogen in piglets and should be included in the routine differential diagnosis of enteric diseases in piglets.
- Published
- 2020
68. 'Omics' of Food-Borne Gastroenteritis: Global Proteomic and Mutagenic Analysis of Salmonella enterica Serovar Enteritidis.
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Arunima, Aryashree, Yelamanchi, Soujanya D., Padhi, Chandrashekhar, Jaiswal, Sangeeta, Ryan, Daniel, Gupta, Bhawna, Sathe, Gajanan, Advani, Jayshree, Gowda, Harsha, Prasad, T.S. Keshava, and Suar, Mrutyunjay
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FOODBORNE diseases , *GASTROENTERITIS , *ENTEROBACTERIACEAE , *MASS spectrometers , *IMMUNITY , *MEMBRANE proteins - Abstract
Salmonella Enteritidis causes food-borne gastroenteritis by the two type three secretion systems (TTSS). TTSS-1 mediates invasion through intestinal lining, and TTSS-2 facilitates phagocytic survival. The pathogens' ability to infect effectively under TTSS-1-deficient background in host's phagocytes is poorly understood. Therefore, pathobiological understanding of TTSS-1-defective nontyphoidal Salmonellosis is highly important. We performed a comparative global proteomic analysis of the isogenic TTSS-1 mutant of Salmonella Enteritidis (M1511) and its wild-type isolate P125109. Our results showed 43 proteins were differentially expressed. Functional annotation further revealed that differentially expressed proteins belong to pathogenesis, tRNA and ncRNA metabolic processes. Three proteins, tryptophan subunit alpha chain, citrate lyase subunit alpha, and hypothetical protein 3202, were selected for in vitro analysis based on their functional annotations. Deletion mutants generated for the above proteins in the M1511 strain showed reduced intracellular survival inside macrophages in vitro. In sum, this study provides mass spectrometry-based evidence for seven hypothetical proteins, which will be subject of future investigations. Our study identifies proteins influencing virulence of Salmonella in the host. The study complements and further strengthens previously published research on proteins involved in enteropathogenesis of Salmonella and extends their role in noninvasive Salmonellosis. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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69. Surface hypothermia predicts murine mortality in the intragastric Vibrio vulnificus infection model.
- Author
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Gavin, Hannah E. and Satchell, Karla J. F.
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HYPOTHERMIA , *ANIMAL mortality , *VIBRIO vulnificus , *SEAFOOD contamination , *LABORATORY mice , *DIAGNOSIS - Abstract
Background: The Gram-negative bacterium Vibrio vulnificus can cause severe disease in humans who consume undercooked, contaminated seafood. To study food-borne V. vulnificus disease in the laboratory, mouse virulence studies predominantly use death as the primary experimental endpoint because behaviorally based moribund status does not consistently predict lethality. This study assessed ventral surface temperature (VST) and its association with mouse survival during V. vulnificus virulence studies as an efficacious, humane alternative. Methods: VST of mice intragastrically inoculated with V. vulnificus was measured every 2-h for 24 h and data for minimal VST analyzed for prediction of lethal outcome. Results: In contrast to the relatively stable VST of mock-infected control animals, mice infected with V. vulnificus exhibited hypothermia with minima occurring 8 to 12 h post-inoculation. The minimum VST of mice that proceeded to death was significantly lower than that of surviving mice. VST ≤ 23.5 °C was predictive of subsequent death with a sensitivity of 68% and specificity of 95%. Conclusions: Use of VST ≤ 23.5 °C as an experimental endpoint during V. vulnificus infection has potential to reduce suffering of nearly 70% of mice for a mean of 10 h per mouse, without compromising experimental efficacy. Temperature cutoff of 23.5 °C exhibited 93% positive and 77% negative predictive value. For future V. vulnificus virulence studies requiring only binary comparison (e.g., LD50 assays), we find that VST can be applied as a humane endpoint. However, use of VST is not recommended when detailed survival kinetics are desired. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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70. Report of the first clinical case of intestinal trichomoniasis caused by Tritrichomonas foetus in a cat with chronic diarrhoea in Brazil.
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Hora, Aline S., Miyashiro, Samantha I., Cassiano, Fabiana C., Brandão, Paulo E., Reche-Junior, Archivaldo, and Pena, Hilda F. J.
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TRICHOMONIASIS , *TRICHOMONAS foetus , *DIARRHEA in animals , *FECAL incontinence - Abstract
Background: Tritrichomonas foetus is an emergent and important enteric pathogen of cats, which causes prolonged diarrhoea in cats. Case presentation: This study describes a T. foetus infection in a seven-month-old, entire male domestic shorthair kitten with a six-month history of persistent large intestinal diarrhoea, faecal incontinence, prostration, apathy and weight loss. Parasites were microscopically observed and confirmed by PCR and DNA sequencing. Molecular analyses were carried out comparing the sequence obtained in this study with T. foetus and T. suis. Retrieved from GenBank. After treatment with ronidazole, the cat showed resolution of clinical signs. Conclusions: This is the first clinical case of T. foetus infection in a chronic diarrheic cat in Brazil and South America, confirming the presence of this pathogen in this part of the world and highlighting the importance of this protozoa being considered in the differential diagnosis of cats presenting diarrhoea of the large intestine. Our case report enriches our knowledge on the geographical distribution of T. foetus in cats in Brazil and provides further understanding of the clinical significance of feline intestinal trichomoniasis in this country. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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71. Salmonella-liberated dietary L-arabinose promotes expansion in superspreaders.
- Author
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Ruddle, Sarah J., Massis, Liliana M., Cutter, Alyssa C., and Monack, Denise M.
- Abstract
The molecular understanding of host-pathogen interactions in the gastrointestinal (GI) tract of superspreader hosts is incomplete. In a mouse model of chronic, asymptomatic Salmonella enterica serovar Typhimurium (S. Tm) infection, we performed untargeted metabolomics on the feces of mice and found that superspreader hosts possess distinct metabolic signatures compared with non-superspreaders, including differential levels of L-arabinose. RNA-seq on S. Tm from superspreader fecal samples showed increased expression of the L-arabinose catabolism pathway in vivo. By combining bacterial genetics and diet manipulation, we demonstrate that diet-derived L-arabinose provides S. Tm a competitive advantage in the GI tract, and expansion of S. Tm in the GI tract requires an alpha- N -arabinofuranosidase that liberates L-arabinose from dietary polysaccharides. Ultimately, our work shows that pathogen-liberated L-arabinose from the diet provides a competitive advantage to S. Tm in vivo. These findings propose L-arabinose as a critical driver of S. Tm expansion in the GI tracts of superspreader hosts. [Display omitted] • S. Tm superspreader mice have distinct gut metabolomes compared with non-superspreaders • S. Tm uses L-arabinose to expand in the GI tract • S. Tm acquires dietary L-arabinose through an alpha- N- arabinofuranosidase (STM0148) • Acquisition of L-arabinose is important for the emergence of S. Tm superspreader mice Ruddle et al. combine metabolomics and transcriptomics to show that the pathogen Salmonella Typhimurium catabolizes L-arabinose in the GI tracts of superspreader mice. They demonstrate that S. Tm uses an alpha- N -arabinofuranosidase to acquire dietary L-arabinose and find this process critical for the emergence of superspreaders. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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72. Neutrophil—epithelial interactions, and efforts to down-regulate them, in inflammatory bowel disease
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Gewirtz, A. T., Madara, J. L., Williams, C. N., editor, Bursey, R. F., editor, Gall, D. G., editor, Martin, F., editor, McLeod, R. S., editor, Sutherland, L. R., editor, and Wallace, J. L., editor
- Published
- 2000
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73. Mechanisms and Impact of Enteric Infections
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Guerrant, Richard L., Lima, Aldo A. M., Barboza, Manuel, Young, Sharon, Silva, Terezinha, Barrett, Leah, Bao, Yongde, Fox, Jay, Moore, Sean, Paul, Prem S., editor, and Francis, David H., editor
- Published
- 1999
- Full Text
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74. Anti-Giardia Drug Discovery: Current Status and Gut Feelings
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Tina S. Skinner-Adams, Christopher J.S. Hart, Katharine R. Trenholme, and Andrew G. Riches
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0303 health sciences ,medicine.medical_specialty ,biology ,Chemistry ,Drug discovery ,Giardia ,Enteric pathogen ,Drug resistance ,biology.organism_classification ,Antimicrobial ,01 natural sciences ,Giardia Infections ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,03 medical and health sciences ,Pharmacotherapy ,parasitic diseases ,Drug Discovery ,medicine ,Molecular Medicine ,Health education ,Intensive care medicine ,030304 developmental biology - Abstract
Giardia parasites are ubiquitous protozoans of global importance that impact a wide range of animals including humans. They are the most common enteric pathogen of cats and dogs in developed countries and infect ∼1 billion people worldwide. While Giardia infections can be asymptomatic, they often result in severe and chronic diseases. There is also mounting evidence that they are linked to postinfection disorders. Despite growing evidence of the widespread morbidity associated with Giardia infections, current treatment options are limited to compound classes with broad antimicrobial activity. Frontline anti-Giardia drugs are also associated with increasing drug resistance and treatment failures. To improve the health and well-being of millions, new selective anti-Giardia drugs are needed alongside improved health education initiatives. Here we discuss current treatment options together with recent advances and gaps in drug discovery. We also propose criteria to guide the discovery of new anti-Giardia compounds.
- Published
- 2020
75. Measuring Environmental Exposure to Enteric Pathogens in Low-Income Settings: Review and Recommendations of an Interdisciplinary Working Group
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Stephen P. Luby, Jill R. Stewart, Thomas Clasen, Frederick G. B. Goddard, John M. Colford, Mami Taniuchi, Matthew C. Freeman, Amy J. Pickering, Karen Levy, Ayse Ercumen, Jeremy A. Sarnat, Radu Ban, Evan A. Thomas, Joseph N. S. Eisenberg, Jennifer L. Cannon, Christine L. Moe, Joe Brown, Helen H. Petach, and Dana B. Barr
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Low income ,Sanitation ,media_common.quotation_subject ,Psychological intervention ,Environmental media ,Enteric pathogen ,010501 environmental sciences ,01 natural sciences ,Feces ,Hygiene ,Environmental health ,Humans ,2.2 Factors relating to the physical environment ,Environmental Chemistry ,Medicine ,Aetiology ,Child ,Preschool ,Poverty ,Disease burden ,0105 earth and related environmental sciences ,media_common ,Pediatric ,business.industry ,Prevention ,Critical Review ,Environmental Exposure ,General Chemistry ,Environmental exposure ,Foodborne Illness ,Infectious Diseases ,Good Health and Well Being ,Clean Water and Sanitation ,Child, Preschool ,Infection ,business ,Environmental Sciences - Abstract
Infections with enteric pathogens impose a heavy disease burden, especially among young children in low-income countries. Recent findings from randomized controlled trials of water, sanitation, and hygiene interventions have raised questions about current methods for assessing environmental exposure to enteric pathogens. Approaches for estimating sources and doses of exposure suffer from a number of shortcomings, including reliance on imperfect indicators of fecal contamination instead of actual pathogens and estimating exposure indirectly from imprecise measurements of pathogens in the environment and human interaction therewith. These shortcomings limit the potential for effective surveillance of exposures, identification of important sources and modes of transmission, and evaluation of the effectiveness of interventions. In this review, we summarize current and emerging approaches used to characterize enteric pathogen hazards in different environmental media as well as human interaction with those media (external measures of exposure), and review methods that measure human infection with enteric pathogens as a proxy for past exposure (internal measures of exposure). We draw from lessons learned in other areas of environmental health to highlight how external and internal measures of exposure can be used to more comprehensively assess exposure. We conclude by recommending strategies for advancing enteric pathogen exposure assessments.
- Published
- 2020
76. Activity of fructose-1,6-bisphosphatase fromCampylobacter jejuni
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Prof.Dr. Peter C. E. Moody and Adnan Ayna
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0303 health sciences ,biology ,Chemistry ,Fructose 1,6-bisphosphatase ,Cell Biology ,Enteric pathogen ,010402 general chemistry ,biology.organism_classification ,01 natural sciences ,Biochemistry ,Campylobacter jejuni ,0104 chemical sciences ,03 medical and health sciences ,Gluconeogenesis ,Metabolic control analysis ,biology.protein ,Glycolysis ,Molecular Biology ,030304 developmental biology ,Phosphofructokinase - Abstract
The glycolytic pathway of the enteric pathogen Campylobacter jejuni is incomplete; the absence of phosphofructokinase means that the suppression of futile cycling at this point in the glycolytic–gluconeogenic pathway might not be required, and therefore the mechanism for controlling pathway flux is likely to be quite different or absent. In this study, the characteristics of fructose-1,6-bisphosphatase (FBPase) of C. jejuni are described and the regulation of this enzyme is compared with the equivalent enzymes from organisms capable of glycolysis. The enzyme is insensitive to AMP inhibition, unlike other type I FBPases. Campylobacter jejuni FBPase also shows limited sensitivity to other glycolytic and gluconeogenic intermediates. The allosteric cooperative control of the enzyme’s activity found in type I FBPases appears to have been lost.
- Published
- 2020
77. Clostridium difficile and One Health
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Daniel R. Knight, Thomas V. Riley, and Su Chen Lim
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0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Web of science ,030106 microbiology ,Enteric pathogen ,03 medical and health sciences ,0302 clinical medicine ,Epidemiology ,Environmental Microbiology ,medicine ,Animals ,Humans ,One Health ,030212 general & internal medicine ,Intensive care medicine ,Cross Infection ,Whole Genome Sequencing ,Clostridioides difficile ,business.industry ,Transmission (medicine) ,Genomic sequencing ,General Medicine ,Clostridium difficile ,Community-Acquired Infections ,Infectious Diseases ,Carrier State ,Clostridium Infections ,Food Microbiology ,business ,Asymptomatic carrier ,Genome, Bacterial - Abstract
Background For over four decades, Clostridium difficile has been a significant enteric pathogen of humans. It is associated with the use of antimicrobials that generally disrupt the microbiota of the gastrointestinal tract. Previously, it was thought that C. difficile was primarily a hospital-acquired infection; however, with the emergence of community-associated cases, and whole-genome sequencing suggesting the majority of the hospital C. difficile infection (CDI) cases are genetically distinct from one another, there is compelling evidence that sources/reservoirs of C. difficile outside hospitals play a significant role in the transmission of CDI. Objectives To review the ‘One Health' aspects of CDI, focusing on how community sources/reservoirs might be acting as a conduit in the transfer of C. difficile between animals and humans. The importance of a One Health approach in managing CDI is discussed. Sources A literature search was performed on PubMed and Web of Science for relevant papers published from 1 January 2000 to 10 July 2019. Content We present evidence that demonstrates transmission of C. difficile in hospitals from asymptomatic carriers to symptomatic CDI patients. The source of colonization is most probably community reservoirs, such as foods and the environment, where toxigenic C. difficile strains have frequently been isolated. With high-resolution genomic sequencing, the transmission of C. difficile between animals and humans can be demonstrated, despite a clear epidemiological link often being absent. The ways in which C. difficile from animals and humans can disseminate through foods and the environment are discussed, and an interconnected transmission pathway for C. difficile involving food animals, humans and the environment is presented. Implications Clostridium difficile is a well-established pathogen of both humans and animals that contaminates foods and the environment. To manage CDI, a One Health approach with the collaboration of clinicians, veterinarians, environmentalists and policy-makers is paramount.
- Published
- 2020
78. Cryptosporidiumspp surveillance and epidemiology in Ireland: a longitudinal cohort study employing duplex real-time PCR based speciation of clinical cases
- Author
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Liam Blake, Jennifer K. O'Leary, Rachel M. Chalmers, Brigid Lucey, Roy D. Sleator, Dan Corcoran, and Kristin Elwin
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Longitudinal study ,biology ,business.industry ,030231 tropical medicine ,030106 microbiology ,Cryptosporidium ,General Medicine ,Enteric pathogen ,biology.organism_classification ,Protozoan parasite ,Pathology and Forensic Medicine ,03 medical and health sciences ,0302 clinical medicine ,Environmental health ,Epidemiology ,medicine ,Epidemiological surveillance ,Longitudinal cohort ,business - Abstract
Cryptosporidiumis a leading cause of gastroenteritis (cryptosporidiosis), with significant morbidity and mortality worldwide. Irish cryptosporidiosis incidence rates are consistently the highest reported in Europe. A retrospective, longitudinal study of clinicalCryptosporidiumisolates was conducted from 2015 to 2018 in Cork, southern Ireland. Overall, 86.5% of cases were attributed toC. parvum, while the remaining 13.5% were caused byC. hominis. Despite the widespread implications of this protozoan parasite in sporadic and outbreak-related illness in Ireland, the current dearth of species-level epidemiological surveillance and clinical studies needs to be addressed in order to elucidate the national impact of this enteric pathogen.
- Published
- 2020
79. Enteric Pathogen Profile and Knowledge, Attitude and Behavior about Food Hygiene among Food Handlers in a Tertiary Health Care Center
- Author
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Dinoop Korol Ponnambath, Rani Rose Mathew, Gautam Roy, and Jharna Mandal
- Subjects
Food hygiene ,Food handlers ,business.industry ,Environmental health ,Health care ,Medicine ,Center (algebra and category theory) ,Enteric pathogen ,business - Published
- 2019
80. Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets
- Author
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Lorena Castillejos, Agustina Rodríguez-Sorrento, Juan José Mallo, Paola López-Colom, Mónica Puyalto, and Susana M. Martín-Orúe
- Subjects
Salmonella ,medicine.drug_class ,Antibiotics ,Microbiota intestinal ,Ileum ,Gut microbiota ,Gut flora ,medicine.disease_cause ,Biochemistry ,Microbiology ,chemistry.chemical_compound ,Cecum ,Enterotoxigenic Escherichia coli ,medicine ,Weaning pig ,lcsh:SF1-1100 ,Enteric pathogen ,Garrins -- Malalties ,lcsh:Veterinary medicine ,biology ,Research ,Medium-chain fatty acids ,biology.organism_classification ,Lauric acid ,Enterobacteriàcies ,Diarrhea ,Garrins -- Alimentació ,medicine.anatomical_structure ,chemistry ,lcsh:SF600-1100 ,Animal Science and Zoology ,Intestinal immunity ,lcsh:Animal culture ,medicine.symptom ,Food Science ,Biotechnology - Abstract
Background The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties, such as medium-chain fatty acids (MCFA) as in-feed additives. This study evaluated the potential of a novel blend of MCFA salts (DIC) from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning. Two experimental disease models were implemented in early-weaned piglets, consisting of two oral challenges: Salmonella Typhimurium (1.2 × 108 CFU) or enterotoxigenic Escherichia coli (ETEC) F4 (1.5 × 109 CFU). The parameters assessed were: animal performance, clinical signs, pathogen excretion, intestinal fermentation, immune-inflammatory response, and intestinal morphology. Results The Salmonella challenge promoted an acute course of diarrhea, with most of the parameters responding to the challenge, whereas the ETEC F4 challenge promoted a mild clinical course. A consistent antipathogenic effect of DIC was observed in both trials in the hindgut, with reductions in Salmonella spp. plate counts in the cecum (P = 0.03) on d 8 post-inoculation (PI) (Salmonella trial), and of enterobacteria and total coliform counts in the ileum and colon (P < 0.10) on d 8 PI (ETEC F4 trial). When analyzing the entire colonic microbiota (16S rRNA gene sequencing), this additive tended (P = 0.13) to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge. In the ETEC F4 challenge, DIC prompted structural changes in the ecosystem with increases in Dialister, and a trend (P = 0.14) to increase the Veillonellaceae family. Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation, nor were the histological parameters. Only the intraepithelial lymphocyte (IEL) counts were lowered by DIC in animals challenged with Salmonella (P = 0.07). With ETEC F4, the IEL counts were higher with DIC on d 8 PI (P = 0.08). Conclusions This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E. coli and its ability to modulate colonic microbiota. These changes could explain to some extent the local immune cell response at the ileal level.
- Published
- 2019
81. Seasonality, shelf life and storage atmosphere are main drivers of the microbiome and E. coli O157:H7 colonization of post-harvest lettuce cultivated in a major production area in California
- Author
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Susan R. Leonard, Ivan Simko, Mark K. Mammel, Taylor K. S. Richter, and Maria T. Brandl
- Subjects
Enteric pathogen ,Microbiota ,Decay ,Applied Microbiology and Biotechnology ,Microbiology ,QR1-502 ,Leafy greens ,Produce ,Environmental sciences ,STEC ,Genetics ,MAP ,GE1-350 ,Cultivar ,Season ,Deterioration ,Research Article - Abstract
Background Lettuce is linked to recurrent outbreaks of Shiga toxin-producing Escherichia coli (STEC) infections, the seasonality of which remains unresolved. Infections have occurred largely from processed lettuce, which undergoes substantial physiological changes during storage. We investigated the microbiome and STEC O157:H7 (EcO157) colonization of fresh-cut lettuce of two cultivars with long and short shelf life harvested in the spring and fall in California and stored in modified atmosphere packaging (MAP) at cold and warm temperatures. Results Inoculated EcO157 declined significantly less on the cold-stored cultivar with short shelf life, while multiplying rapidly at 24 °C independently of cultivar. Metagenomic sequencing of the lettuce microbiome revealed that the pre-storage bacterial community was variable but dominated by species in the Erwiniaceae and Pseudomonadaceae. After cold storage, the microbiome composition differed between cultivars, with a greater relative abundance (RA) of Erwiniaceae and Yersiniaceae on the cultivar with short shelf life. Storage at 24 °C shifted the microbiome to higher RAs of Erwiniaceae and Enterobacteriaceae and lower RA of Pseudomonadaceae compared with 6 °C. Fall harvest followed by lettuce deterioration were identified by recursive partitioning as important factors associated with high EcO157 survival at 6 °C, whereas elevated package CO2 levels correlated with high EcO157 multiplication at 24 °C. EcO157 population change correlated with the lettuce microbiome during 6 °C storage, with fall microbiomes supporting the greatest EcO157 survival on both cultivars. Fall and spring microbiomes differed before and during storage at both temperatures. High representation of Pantoea agglomerans was a predictor of fall microbiomes, lettuce deterioration, and enhanced EcO157 survival at 6 °C. In contrast, higher RAs of Erwinia persicina, Rahnella aquatilis, and Serratia liquefaciens were biomarkers of spring microbiomes and lower EcO157 survival. Conclusions The microbiome of processed MAP lettuce evolves extensively during storage. Under temperature abuse, high CO2 promotes a lettuce microbiome enriched in taxa with anaerobic capability and EcO157 multiplication. In cold storage, our results strongly support a role for season and lettuce deterioration in EcO157 survival and microbiome composition, suggesting that the physiology and microbiomes of fall- and spring-harvested lettuce may contribute to the seasonality of STEC outbreaks associated with lettuce grown in coastal California.
- Published
- 2021
82. Plant Bioactive Compounds as an Intrinsic and Sustainable Tool to Enhance the Microbial Safety of Crops
- Author
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Maria T. Brandl and Andree Sherlon George
- Subjects
Microbiology (medical) ,QH301-705.5 ,enteric pathogen ,Review ,phytochemical ,medicine.disease_cause ,Microbiology ,mitigation ,stress ,Listeria monocytogenes ,Virology ,medicine ,vegetable ,Plant breeding ,Biology (General) ,Abiotic component ,Innate immune system ,biology ,business.industry ,Host (biology) ,fungi ,food and beverages ,fruit ,Antimicrobial ,biology.organism_classification ,foodborne disease ,antagonism ,Biotechnology ,Phytochemical ,Salmonella enterica ,phenolic ,business ,control - Abstract
Outbreaks of produce-associated foodborne illness continue to pose a threat to human health worldwide. New approaches are necessary to improve produce safety. Plant innate immunity has potential as a host-based strategy for the deactivation of enteric pathogens. In response to various biotic and abiotic threats, plants mount defense responses that are governed by signaling pathways. Once activated, these result in the release of reactive oxygen and nitrogen species in addition to secondary metabolites that aim at tempering microbial infection and pest attack. These phytochemicals have been investigated as alternatives to chemical sanitization, as many are effective antimicrobial compounds in vitro. Their antagonistic activity toward enteric pathogens may also provide an intrinsic hurdle to their viability and multiplication in planta. Plants can detect and mount basal defenses against enteric pathogens. Evidence supports the role of plant bioactive compounds in the physiology of Salmonella enterica, Escherichia coli, and Listeria monocytogenes as well as their fitness on plants. Here, we review the current state of knowledge of the effect of phytochemicals on enteric pathogens and their colonization of plants. Further understanding of the interplay between foodborne pathogens and the chemical environment on/in host plants may have lasting impacts on crop management for enhanced microbial safety through translational applications in plant breeding, editing technologies, and defense priming.
- Published
- 2021
83. Attaching and Effacing E. Coli : Microscopic and Ultrastructural Observations of Intestinal Infections in Pigs
- Author
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Higgins, R. J., Pearson, G. R., Wray, C., Paul, Prem S., editor, Francis, David H., editor, and Benfield, David A., editor
- Published
- 1997
- Full Text
- View/download PDF
84. Interactions of Enteric Pathogens with Human Epithelial Cells : Bacterial Exploitation of Host Processes
- Author
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Finlay, B. Brett, Paul, Prem S., editor, Francis, David H., editor, and Benfield, David A., editor
- Published
- 1997
- Full Text
- View/download PDF
85. Interactions between the Enteric Pathogen and the Host : An Assortment of Bacterial Lectins and a Set of Glycoconjugate Receptors
- Author
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Mouricout, Michèle, Paul, Prem S., editor, Francis, David H., editor, and Benfield, David A., editor
- Published
- 1997
- Full Text
- View/download PDF
86. Probiotics of Lactic Acid Bacteria: Science or Myth?
- Author
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Ray, Bibek, Faruk Bozoğlu, T., editor, and Ray, Bibek, editor
- Published
- 1996
- Full Text
- View/download PDF
87. Serological Response to Campylobacter Concisus Infection
- Author
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Zhi, Ning, Revets, H., Van Zeebroek, A., Lauwers, S., Newell, Diane G., editor, Ketley, Julian M., editor, and Feldman, Roger A., editor
- Published
- 1996
- Full Text
- View/download PDF
88. Campylobacter species and Other Enteric Pathogens in HIV-Infected Patients
- Author
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Payen, M.-C., Vlaes, L., Denis, O., Devaster, J.-M., Lior, H., Clumeck, N., Butzler, J.-P., Newell, Diane G., editor, Ketley, Julian M., editor, and Feldman, Roger A., editor
- Published
- 1996
- Full Text
- View/download PDF
89. What's metal got to do with it? Transition metals in Clostridioides difficile infection
- Author
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Christopher A. Lopez, Jay Patel, and Suzanna Y Gomez
- Subjects
Microbiology (medical) ,Multiple stages ,Clostridioides difficile ,Microbiota ,digestive, oral, and skin physiology ,Enteric pathogen ,Nutrients ,Biology ,Microbiology ,Trace Nutrients ,Infectious Diseases ,Immune system ,Clostridium Infections ,Transition Elements ,Humans ,Colonization ,Clostridioides - Abstract
The enteric pathogen Clostridioides difficile overcomes barriers to colonization imposed by the microbiota and host immune response to induce disease. To navigate the dynamic gut environment, C. difficile must respond to dietary and host-mediated fluctuations in transition metal availability. Transition metals are required trace nutrients that foster inter-microbial competition when limited, inhibit bacterial growth through host sequestration, or induce toxicity in excess. This review highlights recent evidence that transition metals influence multiple stages of C. difficile colonization and that C. difficile initiates a coordinated response to maintain metal-dependent homeostasis. Further exploration of the mechanisms of C. difficile metal sensing and nutrient competition with the microbiota will be necessary for the therapeutic manipulation of the gut environment during C. difficile infection.
- Published
- 2021
90. The Problem of Multiresistant Salmonella typhi — use of Molecular Markers in Epidemiology
- Author
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Rowe, Bernard, Threlfall, E. John, Ward, Linda R., Cabello, Felipe, editor, Hormaeche, Carlos, editor, Mastroeni, Pasquale, editor, and Bonina, Letterio, editor
- Published
- 1993
- Full Text
- View/download PDF
91. Changing Trends in Antibiotic Resistance in Salmonella Isolated from Humans in England and Wales
- Author
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Threlfall, E. John, Rowe, Bernard, Ward, Linda R., Cabello, Felipe, editor, Hormaeche, Carlos, editor, Mastroeni, Pasquale, editor, and Bonina, Letterio, editor
- Published
- 1993
- Full Text
- View/download PDF
92. Newly Recognized Bacteria Associated with Gastrointestinal Illness in Humans : Vero Cytotoxin-Producing Escherichia Coli
- Author
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Sherman, Philip, Spiro, Howard M., editor, Thomson, Alan B. R., editor, and Shaffer, Eldon, editor
- Published
- 1992
- Full Text
- View/download PDF
93. Gut flora and disease resistance
- Author
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Hentges, David J. and Fuller, Roy
- Published
- 1992
- Full Text
- View/download PDF
94. The Effect of Human Milk on the Adherence of Enterohemorrhagic E. Coli to Rabbit Intestinal Cells
- Author
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Ashkenazi, Shai, Newburg, David S., Cleary, Thomas G., Mestecky, Jiri, editor, Blair, Claudia, editor, and Ogra, Pearay L., editor
- Published
- 1991
- Full Text
- View/download PDF
95. Campylobacter Infections
- Author
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Taylor, David N., Blaser, Martin J., Evans, Alfred S., editor, and Brachman, Philip S., editor
- Published
- 1991
- Full Text
- View/download PDF
96. Resource Competition and Host Feedbacks Underlie Regime Shifts in Gut Microbiota
- Author
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Christopher A. Klausmeier, Elena Litchman, Ashley Shade, Thomas Koffel, and John Guittar
- Subjects
Resource (biology) ,biology ,Host (biology) ,media_common.quotation_subject ,Microbiota ,Zoology ,Enteric pathogen ,Gut flora ,biology.organism_classification ,Competition (biology) ,Diet ,Feedback ,Gastrointestinal Microbiome ,Chronic infection ,Human gut ,Dysbiosis ,Humans ,Pathogen ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
The spread of an enteric pathogen in the human gut depends on many interacting factors, including pathogen exposure, diet, host gut environment, and host microbiota, but how these factors jointly influence infection outcomes remains poorly characterized. Here we develop a model of host-mediated resource competition between mutualistic and pathogenic taxa in the gut that aims to explain why similar hosts, exposed to the same pathogen, can have such different infection outcomes. Our model successfully reproduces several empirically observed phenomena related to transitions between healthy and infected states, including (1) the nonlinear relationship between pathogen inoculum size and infection persistence, (2) the elevated risk of chronic infection during or after treatment with broad-spectrum antibiotics, (3) the resolution of gut dysbiosis with fecal microbiota transplants, and (4) the potential protection from infection conferred by probiotics. We then use the model to explore how host-mediated interventions-namely, shifts in the supply rates of electron donors (e.g., dietary fiber) and respiratory electron acceptors (e.g., oxygen)-can potentially be used to direct gut community assembly. Our study demonstrates how resource competition and ecological feedbacks between the host and the gut microbiota can be critical determinants of human health outcomes. We identify several testable model predictions ready for experimental validation.
- Published
- 2021
97. Evaluating whole-genome sequencing quality metrics for enteric pathogen outbreaks
- Author
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Eija Trees, Lee S. Katz, Darlene Wagner, and Heather A. Carleton
- Subjects
Whole genome sequencing ,Bioinformatics ,General Neuroscience ,media_common.quotation_subject ,Multiheal ,Assembly ,Outbreak ,SNP ,General Medicine ,Enteric pathogen ,Computational biology ,Genomics ,Read healing ,Biology ,Microbiology ,General Biochemistry, Genetics and Molecular Biology ,Read cleaning ,Medicine ,Quality (business) ,General Agricultural and Biological Sciences ,media_common - Abstract
Background Whole genome sequencing (WGS) has gained increasing importance in responses to enteric bacterial outbreaks. Common analysis procedures for WGS, single nucleotide polymorphisms (SNPs) and genome assembly, are highly dependent upon WGS data quality. Methods Raw, unprocessed WGS reads from Escherichia coli, Salmonella enterica, and Shigella sonnei outbreak clusters were characterized for four quality metrics: PHRED score, read length, library insert size, and ambiguous nucleotide composition. PHRED scores were strongly correlated with improved SNPs analysis results in E. coli and S. enterica clusters. Results Assembly quality showed only moderate correlations with PHRED scores and library insert size, and then only for Salmonella. To improve SNP analyses and assemblies, we compared seven read-healing pipelines to improve these four quality metrics and to see how well they improved SNP analysis and genome assembly. The most effective read healing pipelines for SNPs analysis incorporated quality-based trimming, fixed-width trimming, or both. The Lyve-SET SNPs pipeline showed a more marked improvement than the CFSAN SNP Pipeline, but the latter performed better on raw, unhealed reads. For genome assembly, SPAdes enabled significant improvements in healed E. coli reads only, while Skesa yielded no significant improvements on healed reads. Conclusions PHRED scores will continue to be a crucial quality metric albeit not of equal impact across all types of analyses for all enteric bacteria. While trimming-based read healing performed well for SNPs analyses, different read healing approaches are likely needed for genome assembly or other, emerging WGS analysis methodologies.
- Published
- 2021
98. Clostridioides difficile in bat guano
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Modest Vengust, Petra Bandelj, Primož Presetnik, J. Scott Weese, Joyce Rousseau, Tea Knapič, and Monika Podgorelec
- Subjects
Immunology ,Population ,Zoology ,Enteric pathogen ,Biology ,Ribotyping ,Microbiology ,Feces ,03 medical and health sciences ,Chiroptera ,Prevalence ,medicine ,Animals ,Immunology and Allergy ,education ,030304 developmental biology ,0303 health sciences ,education.field_of_study ,General Veterinary ,Clostridioides difficile ,030306 microbiology ,Transmission (medicine) ,Zoonosis ,General Medicine ,medicine.disease ,3. Good health ,Europe ,Infectious Diseases ,Clostridium Infections ,Clostridioides - Abstract
Bats are associated with the emergence of several mammalian diseases. Their sessional migration, and tendency to form large colonies in close proximity to human habitats enables effective intra- and inter-species transmission of pathogens. Clostridioides difficile is an important enteric pathogen in humans and animals; however, the source of its dissemination in the population is unknown. The purpose of this study was to determine the prevalence of C. difficile in bats, and to characterize C. difficile isolates. Feces (n = 93) was sampled from bats during their migration across Europe. Eighteen samples (19.4%) were positive for C. difficile; ribotypes 078, 056, and a new ribotype CDB3 were identified. Clostridioides difficile ribotypes 078 and 056 are associated with human and animal diseases. The C. difficile prevalence and ribotypes in this study do not necessarily identify bats as a significant source, but more likely as an indicator of C. difficile perpetuation in the environment.
- Published
- 2019
99. Drinking Water Microbiology
- Author
-
Yates, Marylynn V.
- Subjects
Enteric pathogen ,Fecal material ,Indicator organism ,Wastewater ,Coliform bacteria ,Article - Abstract
Every year, on a global basis, billions of cases of illness result from ingestion of microorganisms in drinking water. The majority of these illnesses are caused by fecal contamination, resulting in diarrhea. In places where access to medical care is not readily available, diarrhea can lead to death from dehydration; unfortunately, 1.5 million people, many of whom are children, die annually as a result. There are hundreds of pathogens that may be present in fecal material, making it not feasible to analyze water for all of them. Thus, the microbiological quality of water is monitored using indicator organisms, such as coliform bacteria, enterococci, and/or bacteriophages, which are much simpler and less expensive to detect. The use of indicators, while not perfect, has resulted in a decrease in the incidence of waterborne disease.
- Published
- 2019
100. Confirming the need for virus disinfection in municipal subsurface drinking water supplies
- Author
-
Monica B. Emelko, Philip J. Schmidt, and Mark A. Borchardt
- Subjects
Environmental Engineering ,viruses ,0208 environmental biotechnology ,02 engineering and technology ,Treatment goals ,Enteric pathogen ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,Virus ,Water Supply ,Environmental health ,medicine ,Humans ,Subsurface flow ,Groundwater ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Water Science and Technology ,Civil and Structural Engineering ,Drinking Water ,Ecological Modeling ,Contamination ,Pollution ,6. Clean water ,3. Good health ,020801 environmental engineering ,Disinfection ,Norovirus Genogroup I ,Viruses ,Norovirus ,Environmental science ,Water Microbiology ,Risk assessment - Abstract
Enteric viruses pose the greatest acute human health risks associated with subsurface drinking water supplies, yet quantitative risk assessment tools have rarely been used to develop health-based targets for virus treatment in drinking water sourced from these supplies. Such efforts have previously been hampered by a lack of consensus concerning a suitable viral reference pathogen and dose-response model as well as difficulties in quantifying pathogenic viruses in water. A reverse quantitative microbial risk assessment (QMRA) framework and quantitative polymerase chain reaction data for norovirus genogroup I in subsurface drinking water supplies were used herein to evaluate treatment needs for such water supplies. Norovirus was not detected in over 90% of samples, which emphasizes the need to consider the spatially and/or temporally intermittent patterns of enteric pathogen contamination in subsurface water supplies. Collectively, this analysis reinforces existing recommendations that a minimum 4-log treatment goal is needed for enteric viruses in groundwater in absence of well-specific monitoring information. This result is sensitive to the virus dose-response model used as there is approximately a 3-log discrepancy among virus dose-response models in the existing literature. This emphasizes the need to address the uncertainties and lack of consensus related to various QMRA modelling approaches and the analytical limitations that preclude more accurate description of virus risks.
- Published
- 2019
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