The Experts below are selected from a list of 1671 Experts worldwide ranked by ideXlab platform
Ellie J C Goldstein - One of the best experts on this subject based on the ideXlab platform.
-
Comparative in vitro activity of REP3123 against Clostridium difficile and other anaerobic intestinal bacteria
The Journal of antimicrobial chemotherapy, 2009Co-Authors: Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, Vreni Merriam, Ellie J C GoldsteinAbstract:Objectives: The aim of this study was to determine the anaerobic spectrum of activity of REP3123, a novel diaryldiamine that inhibits bacterial methionyl-tRNA synthetases in Gram-positive bacteria. Methods: Fifty recent clinical isolates of Clostridium difficile from patients diagnosed with C. difficile infection and 223 other intestinal normal flora anaerobes were tested for their susceptibility to REP3123 and four or five comparator agents by the agar dilution method using supplemented Brucella agar with 5% laked sheep blood. Results: All strains of C. difficile were inhibited by 0.5―1 mg/L REP3123, including those resistant to moxifloxacin and clindamycin. REP3123 lacked activity against many normal flora anaerobes in the gut, including Clostridium ramosum, bifidobacteria, lactobacilli of the Lactobacillus casei― rhamnosus―plantarum group and Gram-negative anaerobes. Conclusions: REP3123 demonstrated good potency against C. difficile, but limited activity against many other intestinal anaerobic species, thus, in theory, maintaining the colonization resistance barrier.
-
In Vitro Activities of Daptomycin, Vancomycin, Quinupristin- Dalfopristin, Linezolid, and Five Other Antimicrobials against 307 Gram-Positive Anaerobic and 31 Corynebacterium Clinical Isolates
Antimicrobial agents and chemotherapy, 2003Co-Authors: Ellie J C Goldstein, Diane M. Citron, C. Vreni Merriam, Yumi A. Warren, Kerrin L. Tyrrell, Helen T. FernandezAbstract:The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented Brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) Brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, 8 microg/ml were inhibited by or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by
-
Characterization of Bacteroides forsythus Strains from Cat and Dog Bite Wounds in Humans and Comparison with Monkey and Human Oral Strains
Journal of Clinical Microbiology, 1999Co-Authors: Marie K Hudspeth, D M Citron, S. Hunt Gerardo, M. F. J. Maiden, Ellie J C GoldsteinAbstract:Bacteroides forsythus strains recovered from cat and dog bite wound infections in humans (n = 3), monkey oral strains (n = 3), and the human oral ATCC 43037 type strain were characterized by using phenotypic characteristics, enzymatic tests, whole cell fatty acid analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PCR fingerprinting, and 16S rDNA (genes coding for rRNA) sequencing. All three bite wound isolates grew on Brucella agar supplemented with 5% sheep blood, vitamin K1, and hemin. These strains, unlike the ATCC strain and previously described monkey oral and human clinical strains, did not require N-acetylmuramic acid supplementation for growth as pure cultures. However, their phenotypic characteristics, except for catalase production, were similar to those of previously identified strains. PCR fingerprinting analysis showed differences in band patterns from the ATCC strain. Also, SDS-PAGE and whole cell fatty acid analysis indicated that the dog and cat bite wound strains were similar but not identical to the human B. forsythus ATCC 43037 type strain and the monkey oral strains. The rDNA sequence analysis indicated that the three bite wound isolates had 99.93% homology with each other and 98.9 and 99.22% homology with the human ATCC 43037 and monkey oral strains, respectively. These results suggest that there are host-specific variations within each group.
Diane M. Citron - One of the best experts on this subject based on the ideXlab platform.
-
Comparative in vitro activity of REP3123 against Clostridium difficile and other anaerobic intestinal bacteria
The Journal of antimicrobial chemotherapy, 2009Co-Authors: Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, Vreni Merriam, Ellie J C GoldsteinAbstract:Objectives: The aim of this study was to determine the anaerobic spectrum of activity of REP3123, a novel diaryldiamine that inhibits bacterial methionyl-tRNA synthetases in Gram-positive bacteria. Methods: Fifty recent clinical isolates of Clostridium difficile from patients diagnosed with C. difficile infection and 223 other intestinal normal flora anaerobes were tested for their susceptibility to REP3123 and four or five comparator agents by the agar dilution method using supplemented Brucella agar with 5% laked sheep blood. Results: All strains of C. difficile were inhibited by 0.5―1 mg/L REP3123, including those resistant to moxifloxacin and clindamycin. REP3123 lacked activity against many normal flora anaerobes in the gut, including Clostridium ramosum, bifidobacteria, lactobacilli of the Lactobacillus casei― rhamnosus―plantarum group and Gram-negative anaerobes. Conclusions: REP3123 demonstrated good potency against C. difficile, but limited activity against many other intestinal anaerobic species, thus, in theory, maintaining the colonization resistance barrier.
-
In Vitro Activities of Daptomycin, Vancomycin, Quinupristin- Dalfopristin, Linezolid, and Five Other Antimicrobials against 307 Gram-Positive Anaerobic and 31 Corynebacterium Clinical Isolates
Antimicrobial agents and chemotherapy, 2003Co-Authors: Ellie J C Goldstein, Diane M. Citron, C. Vreni Merriam, Yumi A. Warren, Kerrin L. Tyrrell, Helen T. FernandezAbstract:The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented Brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) Brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, 8 microg/ml were inhibited by or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by
-
Multilaboratory Comparison of Growth Characteristics for Anaerobes, Using 5 Different agar Media
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2002Co-Authors: D. E. Roe, Sydney M. Finegold, E. J. C. Goldstein, Diane M. Citron, Hannah M. Wexler, Jon E. Rosenblatt, M. E. Cox, Stephen G. Jenkins, David W. HechtAbstract:A multilaboratory study compared the growth of 30 fastidious anaerobes, using 5 different agar media: Wilkins-Chalgren (WC), WC with either whole or laked sheep blood, and Brucella supplemented with vitamin K 1 and hemin and either laked or whole sheep blood. The media were compared for quality and quantity of growth. Experiments were conducted either entirely in an anaerobic chamber or inoculated in ambient air with anaerobic incubation. The results showed that (1) any medium plus whole or laked blood was better than unsupplemented WC, (2) whole blood and laked blood additives gave similar results, (3) supplemented Brucella with whole or laked blood was superior to WC and WC with whole or laked blood, and (4) anaerobic and aerobic inoculation with anaerobic incubation gave similar results. Brucella agar supplemented with whole or laked blood supports the growth of fastidious anaerobic species better than the WC agars do.
Kwok-yung Yuen - One of the best experts on this subject based on the ideXlab platform.
-
Leptotrichia hongkongensis sp. nov., a novel Leptotrichia species with the oral cavity as its natural reservoir.
Journal of Zhejiang University. Science. B, 2010Co-Authors: Patrick C. Y. Woo, Samson S. Y. Wong, Jade L. L. Teng, Kit-wah Leung, Antonio H. Y. Ngan, Dong-qing Zhao, Herman Tse, Susanna K. P. Lau, Kwok-yung YuenAbstract:A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BACTEC Plus Anaerobic/F blood culture broth, HKU24T grew on Brucella agar as non-hemolytic, pinpoint colonies after 96 h of incubation at 37 °C in an anaerobic environment and aerobic environment with 5% CO2. Growth was enhanced with a streak of Staphylococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hydrolyzed phenylphosphonate and reduced resazurin. 16S rRNA, groEL, gyrB, recA, and rpoB sequencing showed that HKU24T occupies a distinct phylogenetic position among the Leptotrichia species, being most closely related to Leptotrichia trevisanii. Using HKU24T groEL, gyrB, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenotypic and genotypic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium.
-
Bacteremia in a patient with colonic carcinoma caused by a novel Sedimentibacter species: Sedimentibacter hongkongensis sp. nov.
Diagnostic microbiology and infectious disease, 2004Co-Authors: Patrick C. Y. Woo, Jade L. L. Teng, Kit-wah Leung, Susanna K. P. Lau, Michelle K.m. Wong, Kwok-yung YuenAbstract:A bacterium was isolated from the blood culture of a 91-year-old patient with colonic carcinoma. The cells were strict anaerobic, motile, Gram-negative, sporulating, straight, or slightly curved rods. The bacterium grew on agar using the BACTEC anaerobic blood culture broth or buffered charcoal yeast extract agar as pinpoint colonies after 72 h of incubation at 37 degrees C in anaerobic conditions. It did not grow on blood agar, chocolate agar, MacConkey agar, nutrient agar or broth, brain heart infusion agar or broth, Brucella agar, or cooked meat medium. It produces catalase but not cytochrome oxidase. 16S rRNA gene sequencing and phylogenetic analysis showed that it is closely related to Sedimentibacter hydroxybenzoicus and Sedimentibacter saalensis, with 10.5% and 11.9% differences between the 16S rRNA gene sequence of the bacterium and those of S. hydroxybenzoicus and S. saalensis respectively. A new species, Sedimentibacter hongkongenesis sp. nov., is proposed, for which HKU2(T) is the type strain.
Jamith Basha - One of the best experts on this subject based on the ideXlab platform.
-
An active principle of Nigella sativa L, thymoquinone, showed significant antimicrobial activity against anaerobic bacteria
SAGEYA, 2017Co-Authors: Mohammad A. Randhawa, Awwad Khalaf Alenazy, Majed Alrowaili, Jamith BashaAbstract:Aim/Background: Thymoquinone (TQ) is the major active principle of Nigella sativa seed (Black seed) and is known to control many fungi, bacteria and some viruses. However, the activity of TQ against anaerobic bacteria is not well demonstrated. Anaerobic bacteria can cause severe infections, including diarrhea, aspiration pneumonia and brain abscess, particularly in immune deficient individuals. The present study aimed to investigate the in vitro antimicrobial activity of TQ against some anaerobic pathogens in comparison to metronidazole. Methods: Standard, ATCC, strains of four anaerobic bacteria (Clostridium difficile, Clostridium perfringens, Bacteroides fragilis, and Bacteroides thetaiotaomicron), were initially isolated on special Brucella agar base (With haemin and vitamin K). Then, minimum inhibitory concentrations (MICs) of TQ and metronidazole were determined against these anaerobes when grown in Brucella agar, using serial agar dilution method according to the recommended guidelines for anaerobic organisms instructed by the Clinical and Laboratory Standards Institute (CLSI). Results: TQ showed a significant antimicrobial activity against anaerobic bacteria, although much weaker than metronidazole. MICs of TQ and metronidazole against various anaerobic human pathogens tested were found to be between10-160mg/L and 0.19 to 6.25mg/L, respectively. Conclusions: TQ controlled the anaerobic human pathogenic bacteria, which supports the use of N. sativa in the treatment of diarrhea in folk medicine. Further investigations are in need for determination of the synergistic effect of TQ in combination with metronidazole and the activity of derivatives of TQ against anaerobic infections. [J Complement Med Res 2017; 6(1.000): 97-101
-
An active principle of Nigella sativa L, thymoquinone, showed significant antimicrobial activity against anaerobic bacteria
Journal of intercultural ethnopharmacology, 2016Co-Authors: Mohammad A. Randhawa, Awwad Khalaf Alenazy, Majed Alrowaili, Jamith BashaAbstract:Aim/Background: Thymoquinone (TQ) is the major active principle of Nigella sativa seed (Black seed) and is known to control many fungi, bacteria and some viruses. However, the activity of TQ against anaerobic bacteria is not well demonstrated. Anaerobic bacteria can cause severe infections, including diarrhea, aspiration pneumonia and brain abscess, particularly in immune deficient individuals. The present study aimed to investigate the in vitro antimicrobial activity of TQ against some anaerobic pathogens in comparison to metronidazole. Methods: Standard, ATCC, strains of four anaerobic bacteria (Clostridium difficile, Clostridium perfringens, Bacteroides fragilis, and Bacteroides thetaiotaomicron), were initially isolated on special Brucella agar base (With haemin and vitamin K). Then, minimum inhibitory concentrations (MICs) of TQ and metronidazole were determined against these anaerobes when grown in Brucella agar, using serial agar dilution method according to the recommended guidelines for anaerobic organisms instructed by the Clinical and Laboratory Standards Institute (CLSI). Results: TQ showed a significant antimicrobial activity against anaerobic bacteria, although much weaker than metronidazole. MICs of TQ and metronidazole against various anaerobic human pathogens tested were found to be between10-160mg/L and 0.19 to 6.25mg/L, respectively. Conclusions: TQ controlled the anaerobic human pathogenic bacteria, which supports the use of N. sativa in the treatment of diarrhea in folk medicine. Further investigations are in need for determination of the synergistic effect of TQ in combination with metronidazole and the activity of derivatives of TQ against anaerobic infections.
Yumi A. Warren - One of the best experts on this subject based on the ideXlab platform.
-
Comparative in vitro activity of REP3123 against Clostridium difficile and other anaerobic intestinal bacteria
The Journal of antimicrobial chemotherapy, 2009Co-Authors: Diane M. Citron, Yumi A. Warren, Kerin L. Tyrrell, Vreni Merriam, Ellie J C GoldsteinAbstract:Objectives: The aim of this study was to determine the anaerobic spectrum of activity of REP3123, a novel diaryldiamine that inhibits bacterial methionyl-tRNA synthetases in Gram-positive bacteria. Methods: Fifty recent clinical isolates of Clostridium difficile from patients diagnosed with C. difficile infection and 223 other intestinal normal flora anaerobes were tested for their susceptibility to REP3123 and four or five comparator agents by the agar dilution method using supplemented Brucella agar with 5% laked sheep blood. Results: All strains of C. difficile were inhibited by 0.5―1 mg/L REP3123, including those resistant to moxifloxacin and clindamycin. REP3123 lacked activity against many normal flora anaerobes in the gut, including Clostridium ramosum, bifidobacteria, lactobacilli of the Lactobacillus casei― rhamnosus―plantarum group and Gram-negative anaerobes. Conclusions: REP3123 demonstrated good potency against C. difficile, but limited activity against many other intestinal anaerobic species, thus, in theory, maintaining the colonization resistance barrier.
-
In Vitro Activities of Daptomycin, Vancomycin, Quinupristin- Dalfopristin, Linezolid, and Five Other Antimicrobials against 307 Gram-Positive Anaerobic and 31 Corynebacterium Clinical Isolates
Antimicrobial agents and chemotherapy, 2003Co-Authors: Ellie J C Goldstein, Diane M. Citron, C. Vreni Merriam, Yumi A. Warren, Kerrin L. Tyrrell, Helen T. FernandezAbstract:The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented Brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) Brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, 8 microg/ml were inhibited by or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by
