The Experts below are selected from a list of 1719 Experts worldwide ranked by ideXlab platform
Sanjeev Narayanan - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Cell Based Drug Delivery:Micrococcus luteus Loaded Neutrophils as Chlorhexidine Delivery Vehicles in a Mouse Model of Liver Abscesses in Cattle
2016Co-Authors: Sebastian O Wendel, Sanjeev Narayanan, Sailesh Menon, Hamad Alshetaiwi, Tej B Shrestha, Lauren Chlebanowski, Weiwen Hsu, Stefan H Bossmann, L. TroyerAbstract:The recent WHO report on antibiotic resistances shows a dramatic increase of microbial re-sistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effec-tiveness of a cell based drug delivery system that utilizes the innate immune system as tar-geting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system tar-gets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105
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cell based drug delivery micrococcus luteus loaded neutrophils as chlorhexidine delivery vehicles in a mouse model of liver abscesses in cattle
PLOS ONE, 2015Co-Authors: Sebastian O Wendel, Sanjeev Narayanan, Sailesh Menon, Hamad Alshetaiwi, Tej B Shrestha, Lauren Chlebanowski, Weiwen Hsu, Stefan H Bossmann, Deryl L TroyerAbstract:The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.
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electrophoretic mobility anomalies associated with pcr amplification of the intergenic spacer region between 16s and 23s ribosomal rna genes of Fusobacterium necrophorum
Journal of Microbiological Methods, 2001Co-Authors: Sanjeev Narayanan, T G Nagaraja, M M Chengappa, George C. StewartAbstract:PCR amplification of the intergenic spacer region (ISR) between 16S and 23S rRNA genes among subspecies of the anaerobic bacterium Fusobacterium necrophorum gave identical patterns, with two forms of ISR identified. However, extra bands resulting from anomalous electrophoretic mobility of amplified DNA fragments with certain primer combinations were encountered. Therefore, PCR assays relying solely on banding patterns may be unreliable, and supporting sequence analysis is essential for correct culture identification.
Deryl L Troyer - One of the best experts on this subject based on the ideXlab platform.
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cell based drug delivery micrococcus luteus loaded neutrophils as chlorhexidine delivery vehicles in a mouse model of liver abscesses in cattle
PLOS ONE, 2015Co-Authors: Sebastian O Wendel, Sanjeev Narayanan, Sailesh Menon, Hamad Alshetaiwi, Tej B Shrestha, Lauren Chlebanowski, Weiwen Hsu, Stefan H Bossmann, Deryl L TroyerAbstract:The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.
Sebastian O Wendel - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Cell Based Drug Delivery:Micrococcus luteus Loaded Neutrophils as Chlorhexidine Delivery Vehicles in a Mouse Model of Liver Abscesses in Cattle
2016Co-Authors: Sebastian O Wendel, Sanjeev Narayanan, Sailesh Menon, Hamad Alshetaiwi, Tej B Shrestha, Lauren Chlebanowski, Weiwen Hsu, Stefan H Bossmann, L. TroyerAbstract:The recent WHO report on antibiotic resistances shows a dramatic increase of microbial re-sistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effec-tiveness of a cell based drug delivery system that utilizes the innate immune system as tar-geting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system tar-gets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105
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cell based drug delivery micrococcus luteus loaded neutrophils as chlorhexidine delivery vehicles in a mouse model of liver abscesses in cattle
PLOS ONE, 2015Co-Authors: Sebastian O Wendel, Sanjeev Narayanan, Sailesh Menon, Hamad Alshetaiwi, Tej B Shrestha, Lauren Chlebanowski, Weiwen Hsu, Stefan H Bossmann, Deryl L TroyerAbstract:The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.
Anders Bonde Jensen - One of the best experts on this subject based on the ideXlab platform.
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three variants of the leukotoxin gene in human isolates of Fusobacterium necrophorum subspecies funduliforme
Anaerobe, 2017Co-Authors: Karin Holm, Anders Bonde Jensen, Mattias Collin, Lena Hagelskjaerkristensen, Magnus RasmussenAbstract:Leukotoxin is a well-known virulence factor of animal isolates of Fusobacterium necrophorum subspecies necrophorum, and is also expressed by animal isolates of subspecies funduliforme, whereas its presence in isolates from humans has not been fully established. In this study we found that the leukotoxin gene was present in all tested F. necrophorum isolates from humans. Three sequence variants were found, two of which have not been described previously. The sequence types correlated to source of infection. Further studies are needed to examine the role of the leukotoxin in human infections.
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the role of Fusobacterium necrophorum in pharyngotonsillitis a review
Anaerobe, 2016Co-Authors: Karin Holm, Steffen Bank, L.h. Kristensen, J Prag, Hanne Merete Nielsen, Anders Bonde JensenAbstract:Fusobacterium necrophorum is a gram-negative anaerobic bacterium that is the causative agent of the invasive disease Lemierre's syndrome. In addition, it is also associated with peritonsillar abscess formation and otitis media in small children. Recent research has shown that F. necrophorum may be involved in pharyngotonsillitis especially in adolescent and young adults and that it may be the second most common bacterial cause of pharyngotonsillitis after Streptococcus pyogenes (Group A streptococci). Peritonsillar abscesses and Lemierre's syndrome due to F. necrophorum are also found in this age group, suggesting that they may be complications of F. necrophorum pharyngotonsillitis. In this review we present the present knowledge about the role of F. necrophorum in pharyngotonsillitis with special emphasis on the age distribution. We argue that F. necrophorum is an important pathogen involved in pharyngotonsillitis in the age group of 13–40 years of age and we urge clinical microbiology labs to set up the appropriate techniques to be able to detect F. necrophorum from throat swabs.
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Fusobacterium necrophorum tonsillitis an important cause of tonsillitis in adolescents and young adults
Clinical Microbiology and Infection, 2015Co-Authors: Anders Bonde Jensen, Thomas Michael Hansen, Steffen Bank, L.h. Kristensen, Jørgen PragAbstract:Abstract The role of Fusobacterium necrophorum in tonsillitis in adolescents and young adults was retrospectively investigated by culture examination. We compared the prevalence of F. necrophorum in 212 subjects with confirmed clinical tonsillitis and in 176 subjects with confirmed no clinical tonsillitis. The prevalence of F. necrophorum was significantly higher (p F. necrophorum in tonsillitis. By diagnosing and treating F. necrophorum tonsillitis with, for example, penicillin, metronidazole, or both, we might prevent some cases of Lemierre syndrome.
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minimum requirements for a rapid and reliable routine identification and antibiogram of Fusobacterium necrophorum
European Journal of Clinical Microbiology & Infectious Diseases, 2008Co-Authors: Anders Bonde Jensen, Hagelskjaer L Kristensen, Helle Hvilsted Nielsen, J PragAbstract:Three hundred fifty-seven isolates of Fusobacterium necrophorum from human infections in Denmark were consecutively collected over a 3 year period for the purpose of establishing the minimum requirements for rapid and reliable routine identification of Fusobacterium necrophorum using phenotypic characters. The first 40 isolates were fully characterized by the most common phenotypic tests mentioned in the literature, while the last 317 where identified solely by the established minimum requirements for rapid and reliable routine identification of Fusobacterium necrophorum. All but one isolate were identical in all phenotypic tests. The outlying strain differed in morphology and the ability to agglutinate erythrocytes. On the basis of our findings it should be possible within 3–4 days to identify and differentiate F. necrophorum from other species including other Fusobacterium spp. by the unique but subspecies specific colony morphology, susceptibility to kanamycin and metronidazole, the smell of butyric acid, chartreuse colour fluorescence, and β-haemolysis on horse blood agar. Three-hundred fifty-six isolates were identified as F. necrophorum subsp. funduliforme while one strain was F. necrophorum subsp. necrophorum. The species and subspecies level was confirmed for the first 40 isolates by real-time PCR. MIC in mg/l was determined for the 40 isolates. MIC90 was 0.047 for penicillin, 0.047 for clindamycin, 0.25 for metronidazole, 0.38 for cefuroxime, >32 for imipenem, 0.012 for meropenem, and 2 for erythromycin. All 357 isolates were susceptible to penicillin and metronidazole indicating that these antibiotics are still the drugs of choice in antibiotic therapy of F. necrophorum infections, but therapy with clindamycin may be an alternative. Erythromycin should be avoided.
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detection of Fusobacterium necrophorum subsp funduliforme in tonsillitis in young adults by real time pcr
Clinical Microbiology and Infection, 2007Co-Authors: Anders Bonde Jensen, Hagelskjaer L Kristensen, J PragAbstract:Throat swabs from 61 patients, aged 18-32 years, with non-streptococcal tonsillitis (NST) and 92 healthy controls were examined for the presence of Fusobacterium necrophorum DNA using a novel TaqMan-based real-time quantitative PCR assay for F. necrophorum subspecies. The assay was based on the gyrB subunit gene, and detected F. necrophorum DNA in 48% of patients with NST and in 21% of controls (p <0.001). F. necrophorum subsp. funduliforme was the only subspecies found in both patients and controls. The load of F. necrophorum DNA on swabs from patients with NST was significantly higher than that on swabs from controls (p <0.001). Furthermore, patients with recurrent NST had a significantly higher load of F. necrophorum DNA compared to patients with acute NST (p 0.04). In addition, 26 patients with tonsillitis and group C streptococci (GCS) had a significantly higher load of F. necrophorum DNA compared to the NST group (p <0.001). It was concluded that F. necrophorum subsp. funduliforme is present in small numbers as part of the normal human throat flora, and that F. necrophorum in large quantities may cause tonsillitis, especially recurrent tonsillitis. In addition, the study suggests that the concomitant presence of GCS may aggravate F. necrophorum tonsillitis.
R D Murray - One of the best experts on this subject based on the ideXlab platform.
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high level association of bovine digital dermatitis treponema spp with contagious ovine digital dermatitis lesions and presence of Fusobacterium necrophorum and dichelobacter nodosus
Journal of Clinical Microbiology, 2015Co-Authors: L E Sullivan, S R Clegg, J W Angell, Roger Blowey, J S Duncan, Jennifer Bell, Dai Grovewhite, S D Carter, Kerry Newbrook, R D MurrayAbstract:ABSTRACT Contagious ovine digital dermatitis (CODD) is an important foot disease in sheep, with significant animal welfare and economic implications. It is thought that CODD emerged from bovine digital dermatitis (BDD) via treponemal bacteria. With wildlife species such as elk now suffering a CODD-like disease, it is imperative to clarify these disease etiologies. A large investigation into treponemal association with CODD is warranted. CODD lesions ( n = 58) and healthy sheep foot tissues ( n = 56) were analyzed by PCR for the three BDD-associated Treponema phylogroups and two other lameness-associated bacteria, Dichelobacter nodosus and Fusobacterium necrophorum. Spirochete culture was also attempted on CODD lesions. “Treponema medium/Treponema vincentii-like,” “Treponema phagedenis-like,” and Treponema pedis spirochetes were identified in 39/58 (67%), 49/58 (85%), and 41/58 (71%) of CODD lesions, respectively. One or more BDD-associated Treponema phylogroups were detected in 100% of CODD lesions. Healthy foot tissues did not amplify BDD-associated Treponema phylogroup DNA. D. nodosus and F. necrophorum were present in 34/58 (59%) and 41/58 (71%) of CODD lesions and 22/56 (39%) and 5/56 (9%) of healthy foot tissues, respectively. Thirty-two spirochetes were isolated from CODD lesions, with representatives clustering with, and indistinguishable from, each of the three BDD-associated Treponema phylogroups based on 16S rRNA gene comparisons. This study for the first time demonstrates a high-level association for BDD treponeme phylogroups in CODD and their absence from healthy tissues, supporting the hypothesis that BDD treponemes play a primary causative role in CODD and confirming that the specific PCR assays are an effective differential diagnostic tool for CODD.
