In vivo Model Experiment Using Laying Hens Treated with Enterococcus faecium EM41 from Ostrich Faeces and its Enterocin EM41

AbstractEnterococcus faecium EM41 is an isolate from ostrich faeces. It produces a thermo-stable proteinaceous substance, bacteriocin (enterocin) EM41 with the highest inhibition activity in late logarithmic phase of growth (25 600 AU/ml). This strain and its enterocin have not been previously tested in animals. Lohmann Brown laying hens (aged 45 weeks) were involved in this model/pilot experiment, divided into 3 groups 6 birds in each. E. faecium EM41 applied was a variant treated with rifampicin (109 cfu/ml, dose 400 μl/animal/day) to differentiate it from the other enterococci. Partially-purified enterocin EM41 (Ent EM41, dose 40 μl/animal/day) and its producer were applied to water for 21 days. The experiment lasted 35 days. Sampling was performed at days 0-1, 21 (3 weeks of additive application), 35 (2 weeks after cessation of additive application) from every bird. E. faecium EM41 sufficiently colonized the intestinal tract of laying hens from the initial concentration 109 cfu/g, its count reached 4.30 log cfu/g at day 21. PCR genotypization confirmed the identity of the EM41 strain with the species Enterococcus faecium. E. faecium EM41 and its enterocin EM41 showed antimicrobial effects demonstrated by reduction of coagulase-positive and coagulase-negative staphylococci, coliforms, Pseudomonas spp., Aeromonas spp. and Campylobacter spp. The hens were Salmonella spp. free. After administration of both additives, phagocytic activity was stimulated with a significant increase. The additives did not negatively influence biochemical and haematological parameters or weight gains.

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From formulation to in vivo model: A comprehensive study of a synergistic relationship between vancomycin, carvacrol, and cuminaldehyde against Enterococcus faecium

Phytotherapy Research ◽

10.1002/ptr.6631 ◽

2020 ◽

Vol 34 (7) ◽

pp. 1638-1649 ◽

Cited By ~ 1

Author(s):

Lucy Owen ◽

Joseph P. Webb ◽

Jeffrey Green ◽

Laura J. Smith ◽

Katie Laird

Keyword(s):

Enterococcus Faecium ◽

In Vivo Model ◽

Synergistic Relationship ◽

Comprehensive Study

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The role of Tir, EspA, and NleB in the colonization of cattle by Shiga toxin producingEscherichia coliO26:H11

Canadian Journal of Microbiology ◽

10.1139/w10-059 ◽

2010 ◽

Vol 56 (9) ◽

pp. 739-747 ◽

Cited By ~ 13

Author(s):

Olga Misyurina ◽

David J. Asper ◽

Wanyin Deng ◽

B. Brett Finlay ◽

Dragan Rogan ◽

...

Keyword(s):

Epithelial Cells ◽

Shiga Toxin ◽

Intestinal Tract ◽

In Vivo Model ◽

Intestinal Epithelial ◽

Fecal Shedding ◽

Human Intestinal Epithelial Cells ◽

Uremic Syndrome

Shiga toxin producing Escherichia coli (STEC) O26:H11 is an enteric pathogen capable of causing severe hemorrhagic colitis that can lead to hemolytic uremic syndrome. This organism is able to colonize cattle and human intestinal epithelial cells by secreting effectors via a type III secretion system (T3SS). In this investigation, we examined the role of 2 effectors, Tir and NleB, and the structural translocator component EspA in the adherence of STEC to epithelial cells and in the colonization of cattle. Isogenic deletion mutants were constructed and using microscopy and flow cytometry compared to the wild-type strain in their ability to adhere to HEp-2 cells. A competitive assay was also used to measure the capacity of the mutants to colonize the intestinal tract of cattle, where both the mutant and the parental strains were introduced orally at the same time. Genomic DNA was extracted from enriched fecal samples collected at various time points, and quantitative real-time PCR was used to quantify bacteria. A significant reduction in fecal shedding was observed, and adherence to HEp-2 cells was decreased for the tir and espA mutants. Deletion of the nleB gene did not have a significant effect on the adherence of HEp-2 cells; however, in an in vivo model, it strongly reduced the ability of STEC O26:H11 to colonize the bovine intestinal tract.

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The Cell Wall-Anchored Streptomyces reticuli Avicel-Binding Protein (AbpS) and Its Gene

Journal of Bacteriology ◽

10.1128/jb.180.7.1647-1654.1998 ◽

1998 ◽

Vol 180 (7) ◽

pp. 1647-1654 ◽

Cited By ~ 10

Author(s):

Stefan Walter ◽

Egbert Wellmann ◽

Hildgund Schrempf

Keyword(s):

Reverse Genetics ◽

Binding Protein ◽

Fluorescein Isothiocyanate ◽

Proteinase K ◽

Logarithmic Phase ◽

C Terminus ◽

Late Logarithmic Phase ◽

In Vivo Labelling ◽

Α Helix

ABSTRACT Streptomyces reticuli produces a 35-kDa cellulose-binding protein (AbpS) which interacts strongly with crystalline forms of cellulose (Avicel, bacterial microcrystalline cellulose, and tunicin cellulose); other polysaccharides are recognized on weakly (chitin and Valonia cellulose) or not at all (xylan, starch, and agar). The protein could be purified to homogeneity due to its affinity to Avicel. After we sequenced internal peptides, the corresponding gene was identified by reverse genetics. In vivo labelling experiments with fluorescein isothiocyanate (FITC), FITC-labelled secondary antibodies, or proteinase K treatment revealed that the anchored AbpS protrudes from the surfaces of the hyphae. When we investigated the hydrophobicity of the deduced AbpS, one putative transmembrane segment was predicted at the C terminus. By analysis of the secondary structure, a large centrally located α-helix which has weak homology to the tropomyosin protein family was found. Physiological studies showed that AbpS is synthesized during the late logarithmic phase, independently of the carbon source.

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Activation of isolated heterophils from chicks stimulated in vivo with salmonella enteritidis-immune lymphokines

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166269 ◽

1996 ◽

Vol 54 ◽

pp. 760-761

Author(s):

R. B. Moyes ◽

R. E. Droleskey ◽

M. H. Kogut ◽

J. R. DeLoach

Keyword(s):

Lamina Propria ◽

Intestinal Mucosa ◽

Salmonella Enteritidis ◽

Intestinal Tract ◽

Polymorphonuclear Cells ◽

Subclinical Infection ◽

Egg Products ◽

Immune Lymphokines ◽

Organ Invasion

Salmonella enteritidis (SE) is of great concern to the poultry industry due to the organism's ability to penetrate the intestinal mucosa of the laying hen and subsequently colonize the ovaries and yolk membrane. The resultant subclinical infection can lead to SE infection of raw eggs and egg products. Interference with the ability of the organism to invade has been linked to the activation and recruitment of inflammatory polymorphonuclear cells, heterophils, to the lamina propria of the intestinal tract.Recently it has been established that heterophil activation and increased resistance to SE organ invasion can be accomplished by the administration of SE-immune lymphokines (SE-ILK) obtained from supernatants of concanavalin-A stimulated SE immune T lymphocytes from SE hyperimmunized hens. Invasion of SE into the lamina propria provides a secondary signal for directing activated heterophils to the site of SE invasion.

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Panel Discussion II: Usefulness of in vitro and in vivo Model Systems for Predicting the Adverse Public Health Outcome for Antimicrobial Drug Residues in Food

Microbial Ecology in Health and Disease ◽

10.1080/08910600050216174 ◽

2000 ◽

Vol 12 (3) ◽

pp. 45-53

Author(s):

Andrew Beaulieu ◽

Jacques Boisseau ◽

Carl Cerniglia ◽

Denis Corpet ◽

A. Haydée Fernández ◽

...

Keyword(s):

Public Health ◽

Health Outcome ◽

Panel Discussion ◽

Antimicrobial Drug ◽

Model Systems ◽

In Vivo Model ◽

Drug Residues ◽

Public Health Outcome

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P1735 Arginine supplementation and oxidative processes: in vivo model

European Heart Journal ◽

10.1016/s0195-668x(03)94873-1 ◽

2003 ◽

Vol 24 (5) ◽

pp. 330

Author(s):

A KOPFF

Keyword(s):

In Vivo Model ◽

Oxidative Processes ◽

Arginine Supplementation

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Establishment of an in vivo model for KCNJ5 dependent hyperaldosteronism

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-0035-1547718 ◽

2015 ◽

Vol 122 (03) ◽

Cited By ~ 2

Author(s):

U Lichtenauer ◽

PL Schmid ◽

A Oßwald ◽

I Renner-Müller ◽

M Reincke ◽

...

Keyword(s):

In Vivo Model

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An in vivo Model for the Assessment of Acute Fibrinolytic Capacity of the Endothelium

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657722 ◽

1997 ◽

Vol 78 (04) ◽

pp. 1242-1248 ◽

Cited By ~ 68

Author(s):

David E Newby ◽

Robert A Wright ◽

Christopher A Ludlam ◽

Keith A A Fox ◽

Nicholas A Boon ◽

...

Keyword(s):

Blood Flow ◽

Substance P ◽

Sodium Nitroprusside ◽

Plasma Concentrations ◽

In Vivo Model ◽

Forearm Circulation ◽

Von Willebrand ◽

Local Release ◽

Willebrand Factor

SummaryThe effects on blood flow and plasma fibrinolytic and coagulation parameters of intraarterial substance P, an endothelium dependent vasodilator, and sodium nitroprusside, a control endothelium independent vasodilator, were studied in the human forearm circulation. At subsystemic locally active doses, both substance P (2-8 pmol/min) and sodium nitroprusside (2-8 μg/min) caused dose-dependent vasodilatation (p <0.001 for both) without affecting plasma concentrations of PAI-1, von Willebrand factor antigen or factor VIII:C activity. Substance P caused local increases in t-PA antigen and activity (p <0.001) in the infused arm while sodium nitroprusside did not. At higher doses, substance P increased blood flow and t-PA concentrations in the noninfused arm. We conclude that brief, locally active and subsystemic infusions of intraarterial substance P cause a rapid and substantial local release of t-PA which appear to act via a flow and nitric oxide independent mechanism. This model should provide a useful and selective method of assessing the in vivo capacity of the forearm endothelium to release t-PA acutely.

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