scholarly journals Interaction of Clostridium difficile and Escherichia coli with microfloras in continuous-flow cultures and gnotobiotic mice.

1986 ◽  
Vol 54 (2) ◽  
pp. 354-358 ◽  
Author(s):  
K H Wilson ◽  
R Freter
1980 ◽  
Vol 29 (3) ◽  
pp. 1073-1081
Author(s):  
Rodney D. Berg

Escherichia coli C25 maintained population levels of 10 9 to 10 10 per g of cecum and translocated to 100% of the middle mesenteric lymph nodes in gnotobiotic mice monoassociated with E. coli C25. Intragastric inoculation of these mice with the cecal contents from specific-pathogen-free mice reduced the population levels of E. coli C25 to 10 6 per g of cecum and completely inhibited translocation to the mesenteric lymph nodes. Intragastric inoculation with heat-treated, Formalintreated, or filtered cecal contents did not reduce the population levels of E. coli C25 or reduce the incidence of translocation of E. coli C25 to the mesenteric lymph nodes. Thus, viable bacteria apparently are required in the cecal contents inocula to reduce the population levels and the incidence of translocation of E. coli C25. Treatment with streptomycin plus bacitracin decreased the anaerobic bacterial levels in these gnotobiotic mice, allowing increased population levels of E. coli C25 and increased translocation to the mesenteric lymph nodes. E. coli C25 also translocated to the mesenteric lymph nodes of specific-pathogen-free mice treated with streptomycin and bacitracin before colonization with E. coli C25. The high cecal population levels of E. coli C25 in these antibiotic-decontaminated specific-pathogen-free mice apparently overwhelm any barrier to translocation exerted by the immunologically developed lamina propria of the specific-pathogen-free mice. Inoculation of gnotobiotic mice with a cecal flora also reduced the population levels of an indigenous strain of E. coli with a concomitant inhibition of translocation of the indigenous E. coli to the mesenteric lymph nodes. Thus, bacterial antagonism of the gastrointestinal population levels of certain indigenous bacteria, such as E. coli , by other members of the normal bacterial flora appears to be an important defense mechanism confining bacteria to the gastrointestinal tract.


2013 ◽  
Vol 33 (8) ◽  
pp. 963-969 ◽  
Author(s):  
Eduardo C. Cruz Junior ◽  
Felipe M. Salvarani ◽  
Rodrigo O.S. Silva ◽  
Marcos X. Silva ◽  
Francisco C.F. Lobato ◽  
...  

The purpose of the study was to evaluate the real importance of anaerobic enteropathogens and rotavirus in contrast to more common agents as cause of diarrhea in piglets within the first week of life. Sixty 1- to 7-day-old piglets, 30 diarrheic and 30 non-diarrheic (control), from 15 different herds were selected, euthanized and necropsied. Samples of the jejunum, ileum, colon, cecum and feces were collected from the piglets and analyzed to determine the presence of the following enteropathogens: enterotoxigenic Escherichia coli (ETEC), Clostridium perfringens types A and C, Clostridium difficile, rotavirus and Isospora suis. Among diarrheic piglets, 23.3% were positive for C. difficile, 70% for C. perfringens type A cpb2+, 14.3% for rotavirus and 10% for ETEC. Among non-diarrheic control piglets, 10% were positive for C. difficile, 76.7% for C. perfringens type A cpb2+, 0% for rotavirus, 3.3% for ETEC and 3.3% for I. suis. C. perfringens type C was not detected in any of the animals. Histological lesions characteristic of C. difficile, E. coli and rotavirus were observed. However, no C. perfringens type A suggestive lesions were detected. There was a positive correlation between mesocolon edema and the presence of C. difficile toxins. Although C. perfringens type A cpb2+ was the most frequently detected enteropathogen, there was no association between its presence and diarrhea or macro or microscopic changes. C. difficile and Rotavirus were the most relevant pathogens involved with neonatal diarrhea in this study, and histopathology associated with microbiological test proved to be the key to reach a final diagnosis.


2021 ◽  
Vol 11 ◽  
Author(s):  
Priya J. Sarate ◽  
Dagmar Srutkova ◽  
Nora Geissler ◽  
Martin Schwarzer ◽  
Irma Schabussova ◽  
...  

A steady rise in the number of poly-sensitized patients has increased the demand for effective prophylactic strategies against multi-sensitivities. Probiotic bacteria have been successfully used in clinics and experimental models to prevent allergic mono-sensitization. In the present study, we have investigated whether probiotic bacteria could prevent poly-sensitization by imprinting on the immune system early in life. We used two recombinant variants of probiotic Escherichia coli Nissle 1917 (EcN): i) EcN expressing birch and grass pollen, poly-allergen chimera construct (EcN-Chim), and ii) an “empty” EcN without allergen expression (EcN-Ctrl). Conventional mice (CV) were treated with either EcN-Chim or EcN-Ctrl in the last week of the gestation and lactation period. Gnotobiotic mice received one oral dose of either EcN-Chim or EcN-Ctrl before mating. The offspring from both models underwent systemic allergic poly-sensitization and intranasal challenge with recombinant birch and grass pollen allergens (rBet v 1, rPhl p 1, and rPhl p 5). In the CV setting, the colonization of offspring via treatment of mothers reduced allergic airway inflammation (AAI) in offspring compared to poly-sensitized controls. Similarly, in a gnotobiotic model, AAI was reduced in EcN-Chim and EcN-Ctrl mono-colonized offspring. However, allergy prevention was more pronounced in the EcN-Ctrl mono-colonized offspring as compared to EcN-Chim. Mono-colonization with EcN-Ctrl was associated with a shift toward mixed Th1/Treg immune responses, increased expression of TLR2 and TLR4 in the lung, and maintained levels of zonulin-1 in lung epithelial cells as compared to GF poly-sensitized and EcN-Chim mono-colonized mice. This study is the first one to establish the model of allergic poly-sensitization in gnotobiotic mice. Using two different settings, gnotobiotic and conventional mice, we demonstrated that an early life intervention with the EcN without expressing an allergen is a powerful strategy to prevent poly-sensitization later in life.


2019 ◽  
Vol 35 (12) ◽  
pp. 1008-1013
Author(s):  
Guillaume Desoubeaux ◽  
Mireia Pelegrin

Le développement des anticorps thérapeutiques en infectiologie est beaucoup plus récent qu’en cancérologie, à l’exception d’un anticorps anti-virus respiratoire syncytial (VRS), mais il est désormais un domaine en pleine expansion. À l’échelle mondiale, sept de ces anticorps ont déjà été approuvés par des autorités de santé, dont seulement cinq en France. À ce jour, les indications sont restreintes à la prévention de la bronchiolite liée au VRS, au traitement de la maladie VIH/Sida en échec thérapeutique, à l’exposition au virus de la rage et à la maladie du charbon, à la colite post-antibiotique à Clostridium difficile, et au syndrome hémolytique et urémique atypique à Escherichia coli entéro-hémorragique. Dans un futur proche, l’essor des nouvelles technologies devrait permettre d’accélérer le développement d’anticorps monoclonaux anti-infectieux afin d’étoffer l’arsenal antibiotique et antibactérien déjà à disposition. 


1986 ◽  
Vol 7 (12) ◽  
pp. 607-609 ◽  
Author(s):  
Peter H. Gilligan

In the past 15 years, our knowledge of the pathogenesis and etiologic agents of diarrheal disease has expanded rapidly. No longer is it scientifically appropriate or cost effective for the laboratory simply to culture a stool for Salmonella and Shigella and to do a wet mount for amebae. Today we have a plethora of agents including, but not limited to, Campylobacter, Yersinia, Clostridium difficile, Escherichia coli, Aeromonas, Plesiomonas, vibrios, rotavirus, Norwalk agent, Giardia, and Cryptosporidium, which have all been suggested to be agents of diarrheal disease. Given such a wide range of possibilities, what approaches should be taken to determine the etiologic agent of diarrheal disease in the hospitalized patient in an era of cost containment?


2011 ◽  
Vol 31 (6) ◽  
pp. 505-510 ◽  
Author(s):  
Ricardo T. Lippke ◽  
Sandra M. Borowski ◽  
Sandra M.T. Marques ◽  
Suelen O. Paesi ◽  
Laura L. Almeida ◽  
...  

A case-control study was carried out in litters of 1 to 7-day-old piglets to identify the main infectious agents involved with neonatal diarrhea in pigs. Fecal samples (n=276) from piglets were collected on pig farms in the State of Rio Grande do Sul, Brazil, from May to September 2007. Litters with diarrhea were considered cases (n=129) and normal litters (n=147) controls. The samples were examined by latex agglutination test, PAGE, conventional isolating techniques, ELISA, PCR, and microscopic methods in order to detect rotavirus, bacterial pathogens (Escherichia coli, Clostridium perfringens type A and C, and Clostridium difficile), and parasites (Coccidian and Cryptosporidium spp.). Outbreaks of diarrhea were not observed during sampling. At least one agent was detected in fecal samples on 25 out of 28 farms (89.3%) and in 16 farms (57.1%) more than one agent was found. The main agents diagnosed were Coccidia (42.86%) and rotavirus (39.29%). The main agents identified in litters with diarrhea were Clostridium difficile (10.6%), Clostridium perfringens type A (8.8%) and rotavirus (7.5%); in control litters, Clostridium difficile (16.6%) and Coccidian (8.5%). Beta hemolytic Escherichia coli and Clostridium perfringens type C were not detected. When compared with controls, no agent was significantly associated with diarrhea in case litters. These findings stress the need for caution in the interpretation of laboratorial diagnosis of mild diarrhea in neonatal pigs, as the sole detection of an agent does not necessarily indicate that it is the cause of the problem.


Sign in / Sign up

Export Citation Format

Share Document