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1.
Cell ; 183(3): 666-683.e17, 2020 10 29.
Article in English | MEDLINE | ID: mdl-32991841

ABSTRACT

A mysterious feature of Crohn's disease (CD) is the extra-intestinal manifestation of "creeping fat" (CrF), defined as expansion of mesenteric adipose tissue around the inflamed and fibrotic intestine. In the current study, we explore whether microbial translocation in CD serves as a central cue for CrF development. We discovered a subset of mucosal-associated gut bacteria that consistently translocated and remained viable in CrF in CD ileal surgical resections, and identified Clostridium innocuum as a signature of this consortium with strain variation between mucosal and adipose isolates, suggesting preference for lipid-rich environments. Single-cell RNA sequencing characterized CrF as both pro-fibrotic and pro-adipogenic with a rich milieu of activated immune cells responding to microbial stimuli, which we confirm in gnotobiotic mice colonized with C. innocuum. Ex vivo validation of expression patterns suggests C. innocuum stimulates tissue remodeling via M2 macrophages, leading to an adipose tissue barrier that serves to prevent systemic dissemination of bacteria.


Subject(s)
Adipose Tissue/microbiology , Bacterial Translocation , Gastrointestinal Microbiome , Mesentery/microbiology , Adipose Tissue/pathology , Animals , Biodiversity , Biomarkers/metabolism , Cell Polarity , Cells, Cultured , Colitis, Ulcerative/pathology , Crohn Disease/microbiology , Crohn Disease/pathology , Gastrointestinal Microbiome/genetics , Gene Expression Regulation , Germ-Free Life , Humans , Ileum/microbiology , Ileum/pathology , Lipopolysaccharides/metabolism , Macrophages/metabolism , Metagenome , Metagenomics , Mice , Mice, Inbred C57BL , Phenotype , RNA, Ribosomal, 16S/genetics , Stem Cells/metabolism
2.
Foodborne Pathog Dis ; 17(6): 411-417, 2020 06.
Article in English | MEDLINE | ID: mdl-31809191

ABSTRACT

Salmonellosis is one of the main foodborne diseases worldwide. Breeding sows asymptomatically infected with Salmonella can transmit the pathogen to piglets and humans. The isolation of Salmonella from mesenteric lymph nodes (MLNs) is considered a demonstration of asymptomatic infection in swine. As previous breeding sow studies have been performed using feces, the aim of this work was to study the occurrence of Salmonella infections by sampling MLNs, in comparison to their serological status. First, Salmonella fecal shedding was studied in 12/16 large breeding farms to establish the framework of study. Then, MLN (n = 264) and blood (n = 237) samples were obtained at an abattoir from sows of 15 of these 16 breeding farms. Additionally, risk factors associated with Salmonella MLN infection were analyzed. A total of 6.1% (16/264) sows, distributed in 40% (6/15) of the farms, had the pathogen in MLN. Salmonella Typhimurium was the most frequent serovar isolated. Interestingly, 43.8% (7/16) of MLN isolates were susceptible to all the antimicrobials tested and were found distributed throughout all farms with at least one sow positive. As well, one isolate of the emerging DT195 clone was detected and found to be resistant to six antibiotic families (ASSuTNx-Cfx). The serovars and the resistance profiles of the Salmonella isolates from feces were completely different to those obtained from MLNs. The seroprevalence (41.8% of sows and 100% of farms) was higher than that of MLN infections, showing no concordance (k = 0.15) between these two diagnostic tests in sows. Strategies directed to correct two risk factors (i.e., administration of dry food and old premises) would most likely help to reduce Salmonella infections in breeding sows.


Subject(s)
Feces/microbiology , Lymph Nodes/microbiology , Mesentery/microbiology , Salmonella Infections, Animal/epidemiology , Salmonella Infections, Animal/microbiology , Salmonella/classification , Animals , Anti-Bacterial Agents/pharmacology , Asymptomatic Infections , Bacterial Shedding , Female , Prevalence , Risk Factors , Salmonella/drug effects , Salmonella/isolation & purification , Seroepidemiologic Studies , Serotyping , Swine , Swine Diseases/epidemiology , Swine Diseases/microbiology
3.
Ann Surg Oncol ; 26(13): 4805-4813, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31407185

ABSTRACT

PURPOSE: This study investigated the correlation between the fecal profile and muscle mass, which has not been elucidated before. METHODS: This study included patients who underwent hepatectomy, pancreatoduodenectomy, or esophagectomy and had fecal samples collected preoperatively and mesenteric lymph nodes (MLNs) harvested intraoperatively to determine the fecal profile and presence of bacteria in the MLNs. Total psoas area (TPA) was measured at the third lumbar vertebra using preoperative computed tomography images. TPA was standardized by body surface area (BSA) using the following equation: standardized TPA (mm2/m2) (stTPA) = TPA (mm2)/BSA (m2). The fecal concentrations of representative microorganisms and organic acids also were measured. RESULTS: A total of 127 patients undergoing hepatectomy (n = 48), pancreatoduodenectomy (n = 44), and esophagectomy (n = 35) were included. The fecal levels of predominant obligate anaerobes showed a positive correlation with stTPA, whereas that of pathogenic microorganisms showed a negative correlation with stTPA. The fecal concentrations of total short chain fatty acids (the sum of acetic acid, propionic acid, and butyric acid) also showed a positive correlation with stTPA. The stTPA was significantly lower in patients with positive microorganisms in the MLNs (patients with bacterial translocation) compared to those without microorganisms in the MLNs (p = 0.047). CONCLUSIONS: This study was the first to demonstrate the association between muscle mass and the fecal profile, as well as their association with bacterial translocation.


Subject(s)
Bacteria/metabolism , Bacterial Infections/etiology , Bacterial Translocation , Esophagectomy/adverse effects , Hepatectomy/adverse effects , Pancreaticoduodenectomy/adverse effects , Sarcopenia/etiology , Aged , Bacteria/classification , Bacteria/isolation & purification , Bacterial Infections/diagnosis , Bile Duct Neoplasms/microbiology , Bile Duct Neoplasms/pathology , Bile Duct Neoplasms/surgery , Cross-Sectional Studies , Esophageal Neoplasms/microbiology , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Feces/microbiology , Female , Follow-Up Studies , Humans , Lymph Nodes/microbiology , Male , Mesentery/microbiology , Middle Aged , Pancreatic Neoplasms/microbiology , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Prognosis , Sarcopenia/diagnosis
4.
Infect Immun ; 85(12)2017 12.
Article in English | MEDLINE | ID: mdl-28923895

ABSTRACT

Mycobacterium canettii, which has a smooth colony morphology, is the tuberculous organism retaining the most genetic traits from the putative last common ancestor of the rough-morphology Mycobacterium tuberculosis complex. To explore whether M. canettii can infect individuals by the oral route, mice were fed phosphate-buffered saline or 106M. canettii mycobacteria and sacrificed over a 28-day experiment. While no M. canettii was detected in negative controls, M. canettii-infected mice yielded granuloma-like lesions for 4/4 lungs at days 14 and 28 postinoculation (p.i.) and positive PCR detection of M. canettii for 5/8 mesenteric lymph nodes at days 1 and 3 p.i. and 5/6 pooled stools collected from day 1 to day 28 p.i. Smooth M. canettii colonies grew from 68% of lungs and 36% of spleens and cervical lymph nodes but fewer than 20% of axillary lymph nodes, livers, brown fat samples, kidneys, or blood samples throughout the 28-day experiment. Ready translocation in mice after digestive tract challenge demonstrates the potential of ingested M. canettii organisms to relocate to distant organs and lungs. The demonstration of this relocation supports the possibility that populations may be infected by environmental M. canettii.


Subject(s)
Bacterial Translocation , Mycobacterium/physiology , Tuberculosis, Pulmonary/microbiology , Administration, Oral , Animals , Disease Models, Animal , Lung/microbiology , Lung/pathology , Lymph Nodes/microbiology , Mesentery/microbiology , Mesentery/pathology , Mice , Polymerase Chain Reaction , Spleen/microbiology
5.
PLoS Pathog ; 8(8): e1002828, 2012.
Article in English | MEDLINE | ID: mdl-22876175

ABSTRACT

A highly conserved virulence plasmid encoding a type III secretion system is shared by the three Yersinia species most pathogenic for mammals. Although factors encoded on this plasmid enhance the ability of Yersinia to thrive in their mammalian hosts, the loss of this virulence plasmid does not eliminate growth or survival in host organs. Most notably, yields of viable plasmid-deficient Yersinia pseudotuberculosis (Yptb) are indistinguishable from wild-type Yptb within mesenteric lymph nodes. To identify chromosomal virulence factors that allow for plasmid-independent survival during systemic infection of mice, we generated transposon insertions in plasmid-deficient Yptb, and screened a library having over 20,000 sequence-identified insertions. Among the previously uncharacterized loci, insertions in mrtAB, an operon encoding an ABC family transporter, had the most profound phenotype in a plasmid-deficient background. The absence of MrtAB, however, had no effect on growth in the liver and spleen of a wild type strain having an intact virulence plasmid, but caused a severe defect in colonization of the mesenteric lymph nodes. Although this result is consistent with lack of expression of the type III secretion system by Wt Yptb in the mesenteric lymph nodes, a reporter for YopE indicated that expression of the system was robust. We demonstrate that the ATPase activity of MrtB is required for growth in mice, indicating that transport activity is required for virulence. Indeed, MrtAB appears to function as an efflux pump, as the ATPase activity enhances resistance to ethidium bromide while increasing sensitivity to pyocyanin, consistent with export across the inner membrane.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Bacterial Proteins/metabolism , Lymph Nodes/microbiology , Mesentery/microbiology , RNA-Binding Proteins/metabolism , Transcription Factors/metabolism , Virulence Factors/metabolism , Yersinia pseudotuberculosis Infections/metabolism , Yersinia pseudotuberculosis/pathogenicity , ATP-Binding Cassette Transporters/genetics , Animals , Bacterial Proteins/genetics , Lymph Nodes/metabolism , Lymph Nodes/pathology , Mesentery/metabolism , Mesentery/pathology , Mice , Mice, Inbred BALB C , RNA-Binding Proteins/genetics , Transcription Factors/genetics , Virulence Factors/genetics , Yersinia pseudotuberculosis/genetics , Yersinia pseudotuberculosis/metabolism , Yersinia pseudotuberculosis Infections/genetics , Yersinia pseudotuberculosis Infections/pathology
6.
PLoS Pathog ; 8(11): e1003015, 2012.
Article in English | MEDLINE | ID: mdl-23166492

ABSTRACT

Intestinal Listeria monocytogenes infection is not efficient in mice and this has been attributed to a low affinity interaction between the bacterial surface protein InlA and E-cadherin on murine intestinal epithelial cells. Previous studies using either transgenic mice expressing human E-cadherin or mouse-adapted L. monocytogenes expressing a modified InlA protein (InlA(m)) with high affinity for murine E-cadherin showed increased efficiency of intragastric infection. However, the large inocula used in these studies disseminated to the spleen and liver rapidly, resulting in a lethal systemic infection that made it difficult to define the natural course of intestinal infection. We describe here a novel mouse model of oral listeriosis that closely mimics all phases of human disease: (1) ingestion of contaminated food, (2) a distinct period of time during which L. monocytogenes colonize only the intestines, (3) varying degrees of systemic spread in susceptible vs. resistant mice, and (4) late stage spread to the brain. Using this natural feeding model, we showed that the type of food, the time of day when feeding occurred, and mouse gender each affected susceptibility to L. monocytogenes infection. Co-infection studies using L. monocytogenes strains that expressed either a high affinity ligand for E-cadherin (InlA(m)), a low affinity ligand (wild type InlA from Lm EGDe), or no InlA (ΔinlA) showed that InlA was not required to establish intestinal infection in mice. However, expression of InlA(m) significantly increased bacterial persistence in the underlying lamina propria and greatly enhanced dissemination to the mesenteric lymph nodes. Thus, these studies revealed a previously uncharacterized role for InlA in facilitating systemic spread via the lymphatic system after invasion of the gut mucosa.


Subject(s)
Bacterial Proteins/immunology , Bacterial Translocation/immunology , Foodborne Diseases/immunology , Intestinal Diseases/immunology , Listeria monocytogenes/physiology , Listeriosis/immunology , Lymph Nodes/immunology , Mesentery/immunology , Animals , Bacterial Proteins/genetics , Cadherins/genetics , Cadherins/immunology , Epithelial Cells/immunology , Epithelial Cells/microbiology , Foodborne Diseases/genetics , Foodborne Diseases/microbiology , Foodborne Diseases/pathology , Humans , Intestinal Diseases/genetics , Intestinal Diseases/microbiology , Intestinal Diseases/pathology , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Listeriosis/genetics , Listeriosis/pathology , Lymph Nodes/microbiology , Lymph Nodes/pathology , Mesentery/microbiology , Mesentery/physiology , Mice , Mice, Inbred BALB C
7.
Br J Surg ; 101(3): 189-99, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24402842

ABSTRACT

BACKGROUND: The impact of perioperative synbiotics on bacterial translocation and subsequent bacteraemia after oesophagectomy is unclear. This study investigated the effect of perioperative synbiotic administration on the incidence of bacterial translocation to mesenteric lymph nodes (MLNs) and the occurrence of postoperative bacteraemia. METHODS: Patients with oesophageal cancer were randomized to receive perioperative synbiotics or no synbiotics (control group). MLNs were harvested from the jejunal mesentery before dissection (MLN-1) and after the restoration of digestive tract continuity (MLN-2). Blood and faeces samples were taken before and after operation. Microorganisms in each sample were detected using a bacterium-specific ribosomal RNA-targeted reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) method. RESULTS: Some 42 patients were included. There was a significant difference between the two groups in detection levels of microorganisms in the MLN-1 samples. Microorganisms were more frequently detected in MLN-2 samples in the control group than in the synbiotics group (10 of 18 versus 3 of 18; P = 0·035). In addition, bacteraemia detected using RT-qPCR 1 day after surgery was more prevalent in the control group than in the synbiotics group (12 of 21 versus 4 of 21; P = 0·025). Neutrophil counts on postoperative days 1, 2 and 7 after surgery were all significantly higher in the control group than in the synbiotics group. CONCLUSION: Perioperative use of synbiotics reduces the incidence of bacteria in the MLNs and blood. These beneficial effects probably contribute to a reduction in the inflammatory response after oesophagectomy. REGISTRATION NUMBER: ID 000003262 (University Hospital Medical Information Network, http://www.umin.ac.jp).


Subject(s)
Bacteremia/prevention & control , Bacterial Translocation/physiology , Esophageal Neoplasms/surgery , Esophagectomy/adverse effects , Lymphatic Diseases/prevention & control , Synbiotics , Adult , Aged , C-Reactive Protein/metabolism , Feces/chemistry , Female , Humans , Hydrogen-Ion Concentration , Length of Stay , Leukocyte Count , Lymph Nodes/microbiology , Lymphatic Diseases/microbiology , Male , Mesentery/microbiology , Middle Aged , Perioperative Care/methods
8.
BMC Vet Res ; 10: 59, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24606823

ABSTRACT

BACKGROUND: Salmonellosis is a major worldwide zoonosis, and Salmonella-infected finishing pigs are considered one of the major sources of human infections in developed countries. Baseline studies on salmonellosis prevalence in fattening pigs in Europe are based on direct pathogen isolation from mesenteric lymph nodes (MLN). This procedure is considered the most reliable for diagnosing salmonellosis in apparently healthy pigs. The presence of simultaneous infections by different Salmonella strains in the same animal has never been reported and could have important epidemiological implications. RESULTS: Fourteen finishing pigs belonging to 14 farms that showed high salmonellosis prevalence and a variety of circulating Salmonella strains, were found infected by Salmonella spp, and 7 of them were simultaneously infected with strains of 2 or 3 different serotypes. Typhimurium isolates showing resistance to several antimicrobials and carrying mobile integrons were the most frequently identified in the colonized MLN. Four animals were found infected by Salmonella spp. of a single serotype (Rissen or Derby) but showing 2 or 3 different antimicrobial resistance profiles, without evidence of mobile genetic element exchange in vivo. CONCLUSION: This is the first report clearly demonstrating that pigs naturally infected by Salmonella may harbour different Salmonella strains simultaneously. This may have implications in the interpretation of results from baseline studies, and also help to better understand human salmonellosis outbreaks and the horizontal transmission of antimicrobial resistance genes.


Subject(s)
Lymphatic Diseases/microbiology , Salmonella Infections, Animal/microbiology , Swine Diseases/microbiology , Animals , Disk Diffusion Antimicrobial Tests/veterinary , Drug Resistance, Bacterial , Lymph Nodes/microbiology , Mesentery/microbiology , Salmonella/drug effects , Salmonella typhimurium/drug effects , Serotyping/veterinary , Swine/microbiology
9.
Gut ; 61(1): 78-85, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21940721

ABSTRACT

OBJECTIVE: Mesenteric fat hyperplasia is a hallmark of Crohn's disease (CD), and C reactive protein (CRP) is correlated with disease activity. The authors investigated whether mesenteric adipocytes may be a source of CRP in CD and whether inflammatory and bacterial triggers may stimulate its production by adipocytes. DESIGN: CRP expression in the mesenteric and subcutaneous fats of patients with CD and the correlation between CRP plasma concentrations and mesenteric messenger RNA (mRNA) levels were assessed. The impact of inflammatory and bacterial challenges on CRP synthesis was tested using an adipocyte cell line. Bacterial translocation to mesenteric fat was studied in experimental models of colitis and ileitis and in patients with CD. RESULTS: CRP expression was increased in the mesenteric fat of patients with CD, with mRNA levels being 80 ± 40 (p<0.05) and 140 ± 65 (p=0.04) times higher than in the mesenteric fat of patients with ulcerative colitis and in the subcutaneous fat of the same CD subjects, respectively, and correlated with plasma levels. Escherichia coli (1230 ± 175-fold, p<0.01), lipopolysaccharide (26 ± 0.5-fold, p<0.01), tumour necrosis factor α (15 ± 0.3-fold, p<0.01) and interleukin-6 (10 ± 0.7-fold, p<0.05) increased CRP mRNA levels in adipocyte 3T3-L1 cells. Bacterial translocation to mesenteric fat occurred in 13% and 27% of healthy and CD subjects, respectively, and was increased in experimental colitis and ileitis. Human mesenteric adipocytes constitutively expressed mRNA for TLR2, TLR4, NOD1 and NOD2. CONCLUSION: Mesenteric fat is an important source of CRP in CD. CRP production by mesenteric adipocytes may be triggered by local inflammation and bacterial translocation to mesenteric fat, providing a mechanism whereby mesenteric fat hyperplasia may contribute to inflammatory response in CD.


Subject(s)
Abdominal Fat/metabolism , Bacterial Translocation , C-Reactive Protein/metabolism , Crohn Disease/metabolism , Escherichia coli/physiology , Mesentery/metabolism , Abdominal Fat/microbiology , Adult , Animals , Cell Line , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/microbiology , Crohn Disease/microbiology , Escherichia coli/metabolism , Female , Humans , Ileitis/metabolism , Ileitis/microbiology , Interleukin-6/metabolism , Lipopolysaccharides/metabolism , Lymph Nodes/microbiology , Male , Mesentery/microbiology , Mice , Prospective Studies , Tumor Necrosis Factor-alpha/metabolism
10.
Klin Khir ; (9): 50-4, 2012 Sep.
Article in Ukrainian | MEDLINE | ID: mdl-23285654

ABSTRACT

A chronic intestinal infiltrate model, aiming at a typical inflammatory process simulation, was elaborated in experiment. As a result of experiment on 30 rabbits the quantity of colonies of various causative agents was established, which did not cause the abscess and peritonitis formation. While doing the operation in 60 rabbits chronic infiltrate was formed between abducting and adducting small intestine loops, its mesentery and big omentum; between abducting and adducting large intestine loops, its mesentery and big omentum. The infiltrate formation process was studied up on the 3, 7, 14th and 28th day. Dynamics of changes in microorganisms species and quantity were studied, using microbiological investigations data. The stages of chronic intestinal infiltrate formation were followed up, using histological investigations. Application of the method proposed have permitted to form a chronic infiltrate owing predicted course to reduce the experiment duration and the investigated animals quantity.


Subject(s)
Intestine, Large/pathology , Intestine, Small/pathology , Mesentery/pathology , Omentum/pathology , Peritonitis , Animals , Chronic Disease , Disease Models, Animal , Enterococcus faecalis/growth & development , Escherichia coli/growth & development , Female , Histocytochemistry , Intestine, Large/microbiology , Intestine, Small/microbiology , Male , Mesentery/microbiology , Omentum/microbiology , Peritonitis/microbiology , Peritonitis/pathology , Proteus mirabilis/growth & development , Rabbits , Staphylococcus aureus/growth & development
11.
Infect Immun ; 79(4): 1479-88, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21263018

ABSTRACT

Enteric pathogens can cause relapsing infections in a proportion of treated patients, but greater understanding of this phenomenon is hindered by the lack of appropriate animal models. We report here a robust animal model of relapsing primary typhoid that initiates after apparently successful antibiotic treatment of susceptible mice. Four days of enrofloxacin treatment were sufficient to reduce bacterial loads below detectable levels in all major organs, and mice appeared otherwise healthy. However, any interruption of further antibiotic therapy allowed renewed fecal shedding and renewed bacterial growth in systemic tissues to occur, and mice eventually succumbed to relapsing infection. In vivo imaging of luminescent Salmonella identified the mesenteric lymph nodes (MLNs) as a major reservoir of relapsing infection. A magnetic-bead enrichment strategy isolated MLN-resident CD11b(+) Gr-1(-) monocytes associated with low numbers of persistent Salmonella. However, the removal of MLNs increased the severity of typhoid relapse, demonstrating that this organ serves as a protective filter to restrain the dissemination of bacteria during antibiotic therapy. Together, these data describe a robust animal model of typhoid relapse and identify an important intestinal phagocyte subset involved in protection against the systemic spread of enteric infection.


Subject(s)
Lymph Nodes/microbiology , Monocytes/microbiology , Salmonella Infections, Animal/microbiology , Animals , Anti-Bacterial Agents/therapeutic use , Cell Separation , Disease Models, Animal , Enrofloxacin , Flow Cytometry , Fluoroquinolones/therapeutic use , Intestine, Small/microbiology , Mesentery/immunology , Mesentery/microbiology , Mice , Mice, Inbred C57BL , Monocytes/immunology , Recurrence , Salmonella Infections, Animal/immunology , Salmonella Infections, Animal/pathology , Salmonella typhi/immunology
12.
Appl Environ Microbiol ; 77(22): 8080-7, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21948822

ABSTRACT

The aims of this study were to determine the ability of amplified fragment length polymorphism (AFLP) to differentiate Salmonella isolates from different units of swine production and to demonstrate the relatedness of Salmonella between farms and abattoirs by AFLP. Twenty-four farms in the midwestern United States were visited four times from 2006 to 2009. At each farm or abattoir visit, 30 fecal samples or 30 mesenteric lymph nodes were collected, respectively. A total of 220 Salmonella isolates were obtained, serotyped, and genotyped by multilocus sequence typing (MLST) and AFLP. These 220 isolates clustered into 21 serotypes, 18 MLST types, and 14 predominant AFLP clusters based on a genetic similarity threshold level of 60%. To assess genetic differentiation between farms, harvest cohorts, and pigs, analysis of molecular variance was conducted using AFLP data. The results showed 65.62% of overall genetic variation was attributed to variance among pigs, 27.21% to farms, and 7.17% to harvest cohorts. Variance components at the farm (P = 0.003) and pig (P = 0.001) levels were significant, but not at the harvest cohort level (P = 0.079). A second analysis, a permutation test using AFLP data, indicated that on-farm and at-abattoir Salmonella from pigs of the same farms were more related than from different farms. Therefore, among the three subtyping methods, serotyping, MLST, and AFLP, AFLP was the method that was able to differentiate among Salmonella isolates from different farms and link contamination at the abattoir to the farm of origin.


Subject(s)
Amplified Fragment Length Polymorphism Analysis/methods , Salmonella Infections, Animal/epidemiology , Salmonella enterica/classification , Salmonella enterica/genetics , Swine Diseases/epidemiology , Animals , Cluster Analysis , Feces/microbiology , Genotype , Lymph Nodes/microbiology , Mesentery/microbiology , Midwestern United States/epidemiology , Molecular Epidemiology/methods , Multilocus Sequence Typing , Salmonella Infections, Animal/microbiology , Salmonella enterica/isolation & purification , Serotyping , Swine , Swine Diseases/microbiology
13.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 22(4): 206-9, 2010 Apr.
Article in Zh | MEDLINE | ID: mdl-20398463

ABSTRACT

OBJECTIVE: To observe the effect of mesenteric lymph duct ligation (MLDL) on systemic inflammatory response syndrome (SIRS) and systemic complications in severe acute pancreatitis (SAP) in rats. METHODS: Twenty-four Sprague-Dawley (SD) male rats were randomly divided into sham operation group, SAP group, and SAP+MLDL group, with 8 rats in each group. Sham operation group underwent laparotomy only. SAP complicated with multiple organ injury model was reproduced by retrograde injection of sodium taurocholate into the pancreatic duct in SD rats. In SAP+MLDL group MLDL was performed before reproduction of SAP. Rats were sacrificed at 24 hours after operation. The terminal ileum were collected for examination under light microscope. The samples of pancreas, lung and liver were collected for measuring the level of myeloperoxidase (MPO). The mesenteric lymph nodes were harvested for standard bacteriologic culture. The blood levels of diamine oxidase (DAO), D-lactate, endotoxin, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were also measured. RESULTS: The blood levels of DAO [(0.64 + or - 0.17) kU/L vs. (0.37 + or - 0.07) kU/L], D-lactate [(8.16 + or - 1.79) ng/L vs. (3.24 + or - 1.00) ng/L], endotoxin [(0.068 + or - 0.019) kEU/L vs. (0.033 + or - 0.009) kEU/L], TNF-alpha [(65.21 + or - 13.38) ng/L vs. (22.16 + or - 5.04) ng/L] and IL-6 [(7.95 + or - 1.83) ng/L vs. (4.26 + or - 1.23) ng/L] in SAP group were increased significantly comparing with those in sham operation group (all P<0.01). The contents of pulmonary tissue [(9.07 + or - 2.52) U/g vs. (4.38 + or - 1.29) U/g], pancreatic [(5.14 + or - 1.24) U/g vs. (2.88 + or - 0.75) U/g] and liver [(6.36 + or - 1.63) U/g vs. (3.19 + or - 0.96) U/g] MPO were increased significantly in SAP group comparing with those in sham operation group (all P<0.01). The rate of bacterial translocation to mesenteric lymph nodes in SAP group was significantly higher than that of the sham operation group (75.0% vs. 0, P< 0.01). Compared to SAP group, the contents of DAO [(0.50 + or - 0.13) kU/L], D-lactate [(6.23 + or - 1.25) ng/L] , endotoxin [(0.048 + or - 0.014) kEU/L], TNF-alpha [(48.50 + or - 13.23) ng/L] and IL-6 [(6.06 + or - 1.64) ng/L] were significantly decreased in SAP+MLDL group (P<0.05 or P<0.01). The levels of pulmonary [(6.58 + or - 1.96) U/g], pancreatic [(4.01 + or - 1.05) U/g] and liver [(4.64 + or - 1.34) U/g] MPO, as well as the rate of bacterial translocation to mesenteric lymph nodes (12.5%) were significantly lower in SAP+MLDL group than those in SAP group (all P<0.05). CONCLUSION: MLDL decreases bacteria/ endotoxin translocation and reduces the systemic inflammatory response by interrupting the lymph flow from the injured gut into the bloodstream. This procedure may protect the small intestine mucosal barrier function and other organs by reducing the neutrophil aggregation and the release of cytokines.


Subject(s)
Lymphatic Vessels/surgery , Pancreatitis/complications , Systemic Inflammatory Response Syndrome/prevention & control , Animals , Disease Models, Animal , Interleukin-6/blood , Intestine, Small/pathology , Ligation , Lymph Nodes/microbiology , Male , Mesentery/microbiology , Pancreatitis/pathology , Rats , Rats, Sprague-Dawley , Systemic Inflammatory Response Syndrome/etiology , Tumor Necrosis Factor-alpha/blood
14.
Hepatogastroenterology ; 55(84): 879-82, 2008.
Article in English | MEDLINE | ID: mdl-18705287

ABSTRACT

BACKGROUND/AIMS: Severe hemorrhage may induce bacterial translocation (BT) from the bowel. Presence of hemoperitoneum is supposed to further increase the incidence of BT. METHODOLOGY: Blood was drawn from the femoral artery of rats and hemoperitoneum was created by replacing the drawn blood. Rats were randomly segregated into 5 groups. Control group rats received a sham operation. Rats in groups 1 and 2 received mild hemorrhage (15mL blood/kg body weight withdrawn) with and without hemoperitoneum respectively. Rats in groups 3 and 4 received severe hemorrhage (25mL blood/kg body withdrawn) with and without hemoperitoneum respectively. Twenty-four hours after the above manipulation, mesentery lymph nodes, livers, spleens, and finally cecums were removed for bacterial cultures. RESULTS: Rats that received severe hemorrhage had a significantly higher incidence of BT, both in tissues and in individuals, than rats that received mild hemorrhage did. group 1 rats had a higher incidence of BT in tissues compared with group 2, although the difference in individuals was not significant. On the other hand, group 3 had a higher incidence of BT either in tissues or in individuals compared with group 4. Cecal populations of bacteria assessment showed that groups with hemoperitoneum had higher levels of bacteria in comparison with groups without hemoperitoneum. CONCLUSIONS: Severe hemorrhage in rats increases the incidence of BT and the incidence is even greater in the presence of hemoperitoneum.


Subject(s)
Bacterial Translocation/physiology , Hemoperitoneum/microbiology , Animals , Bacteriological Techniques , Blood Volume/physiology , Cecum/microbiology , Cecum/pathology , Colony Count, Microbial , Enterococcus/physiology , Escherichia coli/physiology , Hemoperitoneum/pathology , Liver/microbiology , Liver/pathology , Lymph Nodes/microbiology , Lymph Nodes/pathology , Male , Mesentery/microbiology , Mesentery/pathology , Proteus/physiology , Pseudomonas/physiology , Rats , Rats, Sprague-Dawley , Spleen/microbiology , Spleen/pathology , Staphylococcus/physiology
15.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 19(5): 266-9, 2007 May.
Article in Zh | MEDLINE | ID: mdl-17490562

ABSTRACT

OBJECTIVE: To observe the changes of toxic substances in mesenteric lymph and portal vein blood of rats in hemorrhagic shock, and the influence of mesenteric lymph duct ligation on level of endotoxin (ET) in organs and bacterial contents in mesenteric lymph nodes (MLN) and spleen in rats with hemorrhagic shock, and to evaluate the role of lymphatic pathway in pathogenesis of intestine-derived bacteria/endotoxin translocation (BET) in rats with shock. METHODS: Twenty-four male Wistar rats were randomly divided into the shock group and control group. A model of serious hemorrhagic shock was reproduced by blood shedding to maintain the blood pressure at 40 mm Hg (1 mm Hg=0.133 kPa) for 90 minutes under aseptic condition, and MLN and portal vein blood were harvested. The specimens were also obtained in control group. The contents of ET, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were determined in them. Thirty male Wistar rats were randomly divided into the sham operation group, shock group and lymphatic duct ligation group. Mesenteric lymph ducts were ligated after resuscitation. All rats were sacrificed, and lung, liver, heart and kidney were removed and homogenized for determination of the content of ET. MLN and spleen homogenates were subjected to bacterial culture. RESULTS: The contents of ET, TNF-alpha and IL-6 in lymph were significantly higher than those of plasma in shock group, and also higher than that in normal plasma and normal lymph (all P<0.01). In shock group the contents of ET in lung, liver, heart and renal homogenate 3 and 6 hours after transfusion and resuscitation were significantly higher than those of sham operation group and ligation group (P<0.05 or P<0.01). Bacterial culture of MLN and spleen in shock group rats 3 and 6 hours after transfusion and resuscitation was positive, but it was not in ligation group. CONCLUSION: The results demonstrate that the intestinal lymphatic pathway plays an important role after compromise of gut barrier function in carrying out BET after hemorrhagic shock.


Subject(s)
Bacterial Translocation , Endotoxins/metabolism , Lymphatic Vessels/physiopathology , Shock, Hemorrhagic/physiopathology , Animals , Disease Models, Animal , Interleukin-6/metabolism , Ligation , Lymph Nodes/microbiology , Lymphatic Vessels/surgery , Male , Mesentery/microbiology , Random Allocation , Rats , Rats, Wistar , Shock, Hemorrhagic/metabolism , Shock, Hemorrhagic/microbiology , Spleen/microbiology , Tumor Necrosis Factor-alpha/metabolism
16.
Chin J Dig Dis ; 7(1): 33-8, 2006.
Article in English | MEDLINE | ID: mdl-16412035

ABSTRACT

OBJECTIVE: The aim of the present study was to test the hypothesis that protein-calorie malnutrition aggravates the gut translocation of Candida albicans triggered by mesenteric ischemia-reperfusion (IR) injury in an experimental model while testing a natural product containing the antifungal anethole/polygodial mixture (Kolorex). METHODS: MFI strain white mice (n = 90) were randomly allocated to a 4-week dietary regimen: (1) standard pellet diet containing 25% casein; (2) low-protein (2.5%) casein diet; (3) as group 2 plus oral supplementation with 20 microL of a 5% solution of Kolorex during the last 4 days. Twenty rats from each of these groups (termed 1a, 2a and 3a) were orally inoculated with Candida suspension 6 h prior to mesenteric IR injury. Animals of each group but without Candida inoculation (termed 1b, 2b and 3b) served as control. A colon permeability study was carried out as well. Rats were killed prior to the IR injury and 3 h afterwards. Control rats were killed at the same time. RESULTS: Over 60% of the mesenteric lymph nodes and 30% of kidney samples were positive for C. albicans in the low-protein-fed rats after IR injury. Kolorex significantly decreased that rate of positivity and also significantly reduced the concentration of C. albicans per gram of each positive tissue sample examined. Protein-calorie malnourished animals showed a statistically significant increase in colon permeability and this phenomenon further increased after IR injury. The groups of rats treated with Kolorex compound showed a partial, although significant, improvement of this parameter. CONCLUSIONS: These results suggest that Kolorex might exert a competitive effect against with C. albicans colonization. The present study represents the first experimental in vivo investigation of the anethole/polygodial-containing compound under the specific conditions of calorie-protein malnutrition and the results have potential clinical interest.


Subject(s)
Antifungal Agents/administration & dosage , Bacterial Translocation/drug effects , Candidiasis/prevention & control , Intestinal Diseases/prevention & control , Protein-Energy Malnutrition/complications , Reperfusion Injury/complications , Allylbenzene Derivatives , Animals , Anisoles/administration & dosage , Candida albicans/physiology , Candidiasis/etiology , Disease Models, Animal , Drug Therapy, Combination , Intestinal Diseases/etiology , Kidney/microbiology , Lymph Nodes/microbiology , Mesentery/microbiology , Rats , Rats, Sprague-Dawley , Sesquiterpenes/administration & dosage
17.
Southeast Asian J Trop Med Public Health ; 37(6): 1237-41, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17333783

ABSTRACT

A cross-sectional study was conducted to determine microbial contamination of pig carcasses at a slaughterhouse in Vientiane, capital of Lao People Democratic Republic (Lao PDR). Between November 2004 and April 2005, 62 pig carcasses were randomly selected. From each carcass, pooled swabs (from "1" prior to and "2" after evisceration) and 25 g of tissue of mesenteric lymph nodes (MLN) were collected. The swab samples were examined for Aerobic Plate Count (APC) and Enterobacteriaceae Counts (EBC) and cultured for Salmonella. The lymph nodes were cultured for Salmonella only. Swabs1 and 2 had mean APC of 4.70 and 4.85 log10CFU/cm2, respectively. These two means were significantly (p = 0.0001) different. The means of EBC were 2.81 log10CFU/cm2 for Swab 1, and 2.98 log10CFU/cm2 for Swab 2. The difference were also statistical significant (p = 0.0001). The frequency of Salmonella isolation from Swab 1 was 46.8%, for Swab 2 was 66.1%, and from mesenteric lymphnodes was 53.2%. Eight different Salmonella serotypes were identified. The most frequent (29.1%) serotype was S. Rissen, followed by S. Anatum (26.2%), S. Derby (18.4%), and S. Elisabethville (8.7%). The other serotypes identified were S. Amsterdam (7.8%), S. Typhimurium (4.9%), S. Agona (2.9%), and S. Enteritidis (1.9%). Results of this study showed the levels of contamination with aerobic bacteria and Enterobacteriaceae were higher than recommended standards, and the carcasses were contaminated with Salmonella.


Subject(s)
Abattoirs/standards , Bacteria, Aerobic/isolation & purification , Food Contamination/analysis , Swine/microbiology , Animals , Bacteria, Aerobic/classification , Cadaver , Colony Count, Microbial/methods , Cross-Sectional Studies , Laos , Lymph Nodes/microbiology , Meat/microbiology , Mesentery/microbiology , Prevalence , Salmonella/isolation & purification , Serotyping
18.
Mucosal Immunol ; 9(2): 492-502, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26349660

ABSTRACT

Dectin-1 is an innate antifungal C-type lectin receptor necessary for protective antifungal immunity. We recently discovered that Dectin-1 is involved in controlling fungal infections of the gastrointestinal (GI) tract, but how this C-type lectin receptor mediates these activities is unknown. Here, we show that Dectin-1 is essential for driving fungal-specific CD4(+) T-cell responses in the GI tract. Loss of Dectin-1 resulted in abrogated dendritic cell responses in the mesenteric lymph nodes (mLNs) and defective T-cell co-stimulation, causing substantial increases in CD4(+) T-cell apoptosis and reductions in the cellularity of GI-associated lymphoid tissues. CD8(+) T-cell responses were unaffected by Dectin-1 deficiency. These functions of Dectin-1 have significant implications for our understanding of intestinal immunity and susceptibility to fungal infections.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Candida albicans/immunology , Candidiasis/immunology , Gastrointestinal Tract/immunology , Lectins, C-Type/immunology , Adoptive Transfer , Animals , Apoptosis/immunology , CD4-Positive T-Lymphocytes/microbiology , CD4-Positive T-Lymphocytes/pathology , CD4-Positive T-Lymphocytes/transplantation , CD8-Positive T-Lymphocytes/microbiology , CD8-Positive T-Lymphocytes/pathology , Candidiasis/genetics , Candidiasis/microbiology , Candidiasis/pathology , Cell Survival/immunology , Female , Gastrointestinal Tract/microbiology , Gastrointestinal Tract/pathology , Gene Expression , Lectins, C-Type/deficiency , Lectins, C-Type/genetics , Lymph Nodes/immunology , Lymph Nodes/microbiology , Lymph Nodes/pathology , Lymphocyte Activation , Mesentery/immunology , Mesentery/microbiology , Mesentery/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout
19.
Hepatogastroenterology ; 52(61): 111-4, 2005.
Article in English | MEDLINE | ID: mdl-15783008

ABSTRACT

BACKGROUND/AIMS: Intraperitoneal hyperthermic perfusion (IPHP) has been used widely in oncologic practice. Hyperthermia is known to decrease the interstitial pressure. Also intraperitoneal hyperthermia may alter the intestinal mucosal barrier and the intestinal bacterial flora. These changes may lead to bacterial translocation (BT). To the best of our knowledge, there is no data about the possible role of IPHP on BT. METHODOLOGY: Fifty-one rats were divided into two groups. Group I (n=36) received IPHP by heated isotonic salt solution at a temperature of of 43.0 degrees C and group II (n=15) received intraperitoneal normothermic lavage by isotonic salt solution at 37.0 degrees C. Each group was divided into three subgroups which were sacrificed at 1st (Ia, IIa), 3rd (Ib, IIb) and 7th (Ic, IIc) days. Mesenteric lymph nodes (MLN), spleen and liver were sampled and cecal aspirates were obtained. The presence of viable bacteria in samples was noted. Cecal bacterial population levels (CBPL) were reported as colony forming units (CFU). Groups were compared in terms of BT and CBPL. RESULTS: BT was not detected in the Ia (IPHP, 1st day) and IIa,b,c (all control groups). However, statistically significant BT was observed in group Ib and Ic (83.3% and 66.6%, respectively) in comparison to control group (p<0.01). Also there was positive correlation between CBPL and BT. CONCLUSIONS: Intraperitoneal hyperthermia causes remarkable BT. This may explain septic complications after IPHP. Further studies are necessary to better understand the effects of IPHP on the pathophysiology of BT.


Subject(s)
Bacterial Translocation , Chemotherapy, Cancer, Regional Perfusion/adverse effects , Escherichia coli/physiology , Hyperthermia, Induced/adverse effects , Isotonic Solutions/administration & dosage , Animals , Escherichia coli/isolation & purification , Infusions, Parenteral , Liver/microbiology , Lymph Nodes/microbiology , Male , Mesentery/microbiology , Rats , Rats, Wistar , Spleen/microbiology
20.
Ulus Travma Acil Cerrahi Derg ; 11(3): 201-5, 2005 Jul.
Article in Turkish | MEDLINE | ID: mdl-16100664

ABSTRACT

BACKGROUND: The objective of our study is to evaluate the preventive effects of selective digestive decontamination (SDD) and mechanical bowel preparation in rats with experimentally induced bacterial translocation. METHODS: Fourty adult male Sprague Dowley rats weighing 250-300 g. were divided equally into four groups as Group 1 (sham [control]), Group 2 (experimentally induced IAH at 19 mmHg), Group 3 ( SDD group) and Group 4 (SDD and mechanical bowel preparation with 19 mmHg intraabdominal pressure). Group 3 and 4 were treated at 12 hours intervals with oral gentamycine 5 mg/kg and IM sefotaxime 100mg/kg Mechanical bowel preparation was performed by oral administration of sodium phosphate. After 24 hours all rats were sacrified; mesenteric lymph nodes, spleen and liver biopsy specimens were harvested aseptically. Specimens were diluted and cultured in McConkey medium and the colony-forming units (CFU/gr ) were calculated. RESULTS: In Kruskal Wallis tests there were no significant differences between Group 1 and 3 or 4, and also Group 3 and 4 (p>0.05, p=0.872 respectively), while differences between Group 1 and 2, and also Group 3 and 4 were statistically significant (p<0.001) with respect to CFU/g estimates. CONCLUSION: These data indicate that selective intestinal decontamination and mechanical bowel preparation prevent bacterial translocation due to intraabdominal hypertension.


Subject(s)
Compartment Syndromes/prevention & control , Gastrointestinal Agents/pharmacology , Gentamicins/pharmacology , Mesentery/drug effects , Sucralfate/pharmacology , Acinetobacter/physiology , Animals , Bacterial Translocation , Colony Count, Microbial , Escherichia coli/physiology , Gastrointestinal Agents/therapeutic use , Gentamicins/therapeutic use , Liver/drug effects , Liver/microbiology , Lymph Nodes/drug effects , Lymph Nodes/microbiology , Male , Mesentery/microbiology , Proteus/physiology , Rats , Rats, Wistar , Spleen/drug effects , Spleen/microbiology , Staphylococcus aureus/physiology , Sucralfate/therapeutic use
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