Establishing an Experimental Infection Model for Peritoneal Dialysis: Effect of Inoculum and Volume

The effect of the number of bacteria and the volume of the inoculum was studied in an experimental infection model to establish a peritoneal dialysis model in the rat. Staphylococcus aureus was used in all experiments, and Staphylococcus epidermidis only in the volume experiments. A bacterial number between 108 and 109 colony forming units (cfu) resulted in a time-dependent decrease of bacteria collected from the peritoneal cavity. Higher concentrations resulted in the death of animals, while lower concentrations were rapidly cleared. There was a positive correlation between the volume in which 3 x 108 cfu were dissolved and the number of bacteria isolated from the peritoneal cavity 24 hours after infection. The results of this study led to an experimental dialysis model using 10 mL of dialysis fluid and 0.5 mL of a suspension containing 3 x 108 cfu of Staphylococcus aureus.

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A pasture-based experimental infection model for footrot in sheep

Small Ruminant Research ◽

10.1016/j.smallrumres.2020.106305 ◽

2020 ◽

pp. 106305

Author(s):

Andrew S. McPherson ◽

Richard J. Whittington ◽

Ruth M. Kennan ◽

Julian I. Rood ◽

Om P. Dhungyel

Keyword(s):

Experimental Infection ◽

Infection Model ◽

Experimental Infection Model

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Whip-LAMP: a novel LAMP assay for the detection of Trichuris muris-derived DNA in stool and urine samples in a murine experimental infection model

Parasites & Vectors ◽

10.1186/s13071-020-04435-1 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Pedro Fernández-Soto ◽

Carlos Fernández-Medina ◽

Susana Cruz-Fernández ◽

Beatriz Crego-Vicente ◽

Begoña Febrer-Sendra ◽

...

Keyword(s):

Molecular Diagnosis ◽

Experimental Infection ◽

Lamp Assay ◽

Diagnostic Methods ◽

Urine Samples ◽

Infection Model ◽

Trichuris Muris ◽

Stool Samples ◽

First Time ◽

Experimental Infection Model

Abstract Background Trichuris trichiura (human whipworm) infects an estimated 477 million individuals worldwide. In addition to T. trichiura, other Trichuris species can cause an uncommon zoonosis and a number of human cases have been reported. The diagnosis of trichuriasis has relied traditionally on microscopy. Recently, there is an effort to use molecular diagnostic methods, mainly qPCR. LAMP technology could be an alternative for qPCR especially in low-income endemic areas. Trichuris muris, the causative agent of trichuriasis in mice, is of great importance as a model for human trichuriasis. Here, we evaluate the diagnostic utility of a new LAMP assay in an active experimental mouse trichuriasis in parallel with parasitological method by using stool and, for the first time, urine samples. Methods Stool and urine samples were collected from mice infected with eggs of T. muris. The dynamics of infection was determined by counting the number of eggs per gram of faeces. A LAMP based on the 18S rRNA gene from T. muris was designed. Sensitivity and specificity of LAMP was tested and compared with PCR. Stool and urine samples were analysed by both LAMP and PCR techniques. Results Trichuris muris eggs were detected for the first time in faeces 35 days post-infection. LAMP resulted specific and no cross-reactions were found when using 18 DNA samples from different parasites. The detection limit of the LAMP assay was 2 pg of T. muris DNA. When testing stool samples by LAMP we obtained positive results on day 35 p.i. and urine samples showed amplification results on day 20 p.i., i.e. 15 days before the onset of T. muris eggs in faeces. Conclusions To the best of our knowledge, we report, for the first time, a novel LAMP assay (Whip-LAMP) for sensitive detection of T. muris DNA in both stool and urine samples in a well-established mice experimental infection model. Considering the advantages of urine in molecular diagnosis in comparison to stool samples, should make us consider the possibility of starting the use urine specimens in molecular diagnosis and for field-based studies of human trichuriasis where possible. Further studies with clinical samples are still needed.

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Development of a Human Experimental Infection Model of Respiratory Syncytial Virus (RSV) and Evaluation of an RNA Interference (RNAi) Therapeutic for Safety and Anti-Viral Efficacy in Man

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2007.12.1064 ◽

2008 ◽

Vol 121 (2) ◽

pp. S268-S268

Author(s):

J DEVINCENZO ◽

R LAMBKINWILLIAMS ◽

J CEHELSKY ◽

T WILKINSON ◽

O OBUTE ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Rna Interference ◽

Experimental Infection ◽

Infection Model ◽

Syncytial Virus ◽

Experimental Infection Model

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Experimental infection model for Sin Nombre hantavirus in the deer mouse (Peromyscus maniculatus)

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.180197197 ◽

2000 ◽

Vol 97 (19) ◽

pp. 10578-10583 ◽

Cited By ~ 126

Author(s):

J. Botten ◽

K. Mirowsky ◽

D. Kusewitt ◽

M. Bharadwaj ◽

J. Yee ◽

...

Keyword(s):

Experimental Infection ◽

Peromyscus Maniculatus ◽

Deer Mouse ◽

Infection Model ◽

Experimental Infection Model

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Bacterial survival and biofilm formation on conventional and antibacterial toothbrushes

Biofilms ◽

10.1017/s1479050504001334 ◽

2004 ◽

Vol 1 (2) ◽

pp. 123-130 ◽

Cited By ~ 8

Author(s):

R. L. Sammons ◽

D. Kaur ◽

P. Neal

Keyword(s):

Pseudomonas Aeruginosa ◽

Staphylococcus Epidermidis ◽

Biofilm Formation ◽

Bacterial Survival ◽

Opportunistic Pathogens ◽

Mechanical Agitation ◽

Gram Staining ◽

Colony Forming Units ◽

Significant Difference ◽

Number Of Bacteria

The aim of this study was to investigate bacterial survival and biofilm formation on toothbrushes. Fifteen healthy volunteers each used a normal toothbrush and an antibacterial toothbrush of the same design for two separate 5 week periods. Bacteria were removed from the brush head by swabbing and mechanical agitation in 10ml of tryptone soya broth, cultured aerobically on selective and non-selective media, and classified by Gram staining, catalase and oxidase tests. Survival of Staphylococcus epidermidis and Pseudomonas aeruginosa was monitored in the laboratory on both types of brush over 8 days. Scanning electron microscopy was used to observe biofilm formation on antibacterial and conventional brushes used for various times. Numbers of bacteria isolated from conventional and antibacterial brushes from different individuals ranged from 8.3×103 to 4.7×106 and from 1×102 to 1.2×106 colony-forming units/ml, respectively. A larger number of bacteria were isolated from conventional brushes than from antibacterial brushes used by the same individuals but no statistically significant difference was demonstrated. No differences in the relative proportions of Gram-negative and Gram-positive rods or cocci were seen. Staphylococci, presumptive coliforms and pseudomonads were isolated from 48%, 28% and 16% of brushes, respectively. Pseudomonas aeruginosa was viable for at least 4 days on conventional, and 2–3 days on antibacterial, brushes, whilst S. epidermidis survived for 6–8 days on antibacterial and more than 8 days on conventional brushes. Biofilms formed on the heads and bristles of both conventional and antibacterial brushes. Extensive, mixed community biofilms developed after several months of use. We conclude that toothbrushes may be a reservoir of opportunistic pathogens including staphylococci and pseudomonad-like organisms and must be considered as a potential source of haematogenous infections and cross-infection.

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Establishment of a novel tick-Babesia experimental infection model

Scientific Reports ◽

10.1038/srep37039 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 6

Author(s):

Hiroki Maeda ◽

Takeshi Hatta ◽

M Abdul Alim ◽

Daigo Tsubokawa ◽

Fusako Mikami ◽

...

Keyword(s):

Experimental Infection ◽

Infection Model ◽

Experimental Infection Model

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Cynomolgus Monkeys (Macaca fascicularis) as an Experimental Infection Model for Human Group A Rotavirus

Viruses ◽

10.3390/v10070355 ◽

2018 ◽

Vol 10 (7) ◽

pp. 355 ◽

Cited By ~ 2

Author(s):

Gentil Bentes ◽

Juliana Guimarães ◽

Eduardo Volotão ◽

Alexandre Fialho ◽

Cleber Hooper ◽

...

Keyword(s):

Experimental Infection ◽

Macaca Fascicularis ◽

Infection Model ◽

Human Group ◽

Cynomolgus Monkeys ◽

Group A Rotavirus ◽

Group A ◽

Experimental Infection Model

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Large-Scale Screening and Identification of Novel Pathogenic Staphylococcus aureus Genes Using a Silkworm Infection Model

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa004 ◽

2020 ◽

Vol 221 (11) ◽

pp. 1795-1804 ◽

Cited By ~ 3

Author(s):

Atmika Paudel ◽

Hiroshi Hamamoto ◽

Suresh Panthee ◽

Yasuhiko Matsumoto ◽

Kazuhisa Sekimizu

Keyword(s):

Staphylococcus Aureus ◽

Large Scale ◽

Opportunistic Pathogen ◽

Infection Model ◽

Colony Forming Units ◽

Screening And Identification ◽

Transposon Mutants ◽

Pathogenicity Tests ◽

Large Scale Screening

Abstract The regulatory network of virulence factors produced by the opportunistic pathogen Staphylococcus aureus is unclear and the functions of many uncharacterized genes in its genome remain to be elucidated. In this study, we screened 380 genes whose function was unassigned, utilizing gene-disrupted transposon mutants of the community-acquired methicillin-resistant S. aureus USA300 for pathogenicity in silkworms. We identified 10 strains with reduced silkworm killing ability. Among them, 8 displayed reduced virulence in a mouse model as evidenced by reduced colony-forming units in organs of infected mice. The role of each gene in pathogenicity was further confirmed by complementation and pathogenicity tests in silkworms, where we found that the phenotype was not restored in 1 strain. Additionally, some of the mutants displayed reduced hemolysis, proteolysis, pigment production, and survival in murine RAW 264.7 monocyte-macrophage cells. These newly identified genes involved in virulence will enhance our understanding of the pathogenicity of S. aureus.

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