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Antimicrobial Agents and Chemotherapy Sep 1999Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory... (Comparative Study)
Comparative Study
Gemifloxacin mesylate (SB 265805), a new fluoronaphthyridone, was tested against 359 recent clinical anaerobic isolates by the National Committee for Clinical Laboratory Standards reference agar dilution method with supplemented brucella blood agar and an inoculum of 10(5) CFU/spot. Comparative antimicrobials tested included trovafloxacin, levofloxacin, grepafloxacin, sparfloxacin, sitafloxacin (DU-6859a), penicillin G, amoxicillin clavulanate, imipenem, cefoxitin, clindamycin, and metronidazole. The MIC(50) and MIC(90) (MICs at which 50 and 90% of the isolates were inhibited) of gemifloxacin against various organisms (with the number of strains tested in parentheses) were as follows (in micrograms per milliliter): for Bacteroides fragilis (28), 0.5 and 2; for Bacteroides thetaiotaomicron (24), 1 and 16; for Bacteroides caccae (12), 1 and 16; for Bacteroides distasonis (12), 8 and >16; for Bacteroides ovatus (12), 4 and >16; for Bacteroides stercoris (12), 0.5 and 0.5; for Bacteroides uniformis (12), 1 and 4; for Bacteroides vulgatus (11), 4 and 4; for Clostridium clostridioforme (15), 0.5 and 0.5; for Clostridium difficile (15), 1 and >16; for Clostridium innocuum (13), 0.125 and 2; for Clostridium perfringens (13), 0.06 and 0.06; for Clostridium ramosum (14), 0.25 and 8; for Fusobacterium nucleatum (12), 0.125 and 0.25; for Fusobacterium necrophorum (11), 0.25 and 0.5; for Fusobacterium varium (13), 0.5 and 1; for Fusobacterium spp. (12), 1 and 2; for Peptostreptococcus anaerobius (13), 0.06 and 0.06; for Peptostreptococcus asaccharolyticus (13), 0.125 and 0.125; for Peptostreptococcus magnus (14), 0.03 and 0.03; for Peptostreptococcus micros (12), 0.06 and 0.06; for Peptostreptococcus prevotii (14), 0.06 and 0.25; for Porphyromonas asaccharolytica (11), 0.125 and 0.125; for Prevotella bivia (10), 8 and 16; for Prevotella buccae (10), 2 and 2; for Prevotella intermedia (10), 0.5 and 0.5; and for Prevotella melaninogenica (11), 1 and 1. Gemifloxacin mesylate (SB 265805) was 1 to 4 dilutions more active than trovafloxacin against fusobacteria and peptostreptococci, and the two drugs were equivalent against clostridia and P. asaccharolytica. Gemifloxacin was equivalent to sitafloxacin (DU 6859a) against peptostreptococci, C. perfringens, and C. ramosum, and sitafloxacin was 2 to 3 dilutions more active against fusobacteria. Sparfloxacin, grepafloxacin, and levofloxacin were generally less active than gemifloxacin against all anaerobes.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Bacteria, Anaerobic; Fluoroquinolones; Gemifloxacin; Microbial Sensitivity Tests; Naphthyridines; Therapeutic Equivalency
PubMed: 10471570
DOI: 10.1128/AAC.43.9.2231 -
Gut Jan 2003Bacteria are implicated in certain forms of model chronic colitis but the identity and role of bacteria in human ulcerative colitis (UC) are uncertain.
BACKGROUND
Bacteria are implicated in certain forms of model chronic colitis but the identity and role of bacteria in human ulcerative colitis (UC) are uncertain.
AIMS
To isolate pathogenic bacteria from inflamed mucosa of patients with UC, to examine whether the bacteria have a toxin to Vero cells, and to determine whether the toxin induces UC-like lesions in animals.
METHODS
Bacteria were isolated from UC patients and supernatants from cultures were filtered and tested for cytotoxicity to Vero cells. Bacterial cells producing the cytotoxic supernatants were examined by polymerase chain reaction for verotoxin genes. Culture supernatants of cytotoxic strains were examined by high performance liquid chromatography for organic acid concentrations. Mice were given enemas containing organic acid at the mean concentration in the supernatants of cytotoxic strains to ascertain whether colonic lesions appear in UC.
RESULTS
Only supernatants from cultures of Fusobacterium varium killed Vero cells. Bacterial cells lacked verotoxin genes. Bacterial culture supernatants contained high concentrations of n-butyric acid and the mean concentration (32 mmol/l) was cytotoxic to Vero cells. Twenty four hours after mice were given enemas containing either butyric acid or F varium culture supernatants, colonic ulcers with crypt abscesses, inflammatory cell infiltration, and apoptotic changes were observed.
CONCLUSIONS
Butyric acid in culture supernatants from cultures of F varium caused UC-like lesions in mice. This study indicates that F varium may be one of the elusive pathogenic factors in UC.
Topics: Adult; Animals; Bacteriological Techniques; Butyric Acid; Colitis, Ulcerative; Colon; Female; Fusobacterium; Fusobacterium Infections; Humans; Intestinal Mucosa; Male; Mice; Mice, Inbred CBA; RNA, Messenger; Shiga Toxins; Statistics, Nonparametric
PubMed: 12477765
DOI: 10.1136/gut.52.1.79 -
Genes Nov 2020The microbiota is the community of microorganisms that colonizes the oral cavity, respiratory tract, and gut of multicellular organisms. The microbiota exerts manifold...
The microbiota is the community of microorganisms that colonizes the oral cavity, respiratory tract, and gut of multicellular organisms. The microbiota exerts manifold physiological and pathological impacts on the organism it inhabits. A growing body of attention is being paid to host-microbiota interplay, which is highly relevant to the development of carcinogenesis. Adenomatous polyps are considered a common hallmark of colorectal cancer, the second leading cause of carcinogenesis-mediated death worldwide. In this study, we examined the relevance between targeted operational taxonomic units and colonic polyps using short- and long-read sequencing platforms. The gut microbiota was assessed in 132 clinical subjects, including 53 healthy participants, 36 patients with occult blood in the gut, and 43 cases with adenomatous polyps. An elevation in the relative abundance of , , and was identified in patients with adenomatous polyps compared with the other groups using long-read sequencing workflow. In contrast, the relatively high abundances of , , and were characterized in the healthy groups. The diversities in gut microbiota communities were similar in all recruited samples. These results indicated that alterations in gut microbiota were characteristic of participants with adenomatous polyps, which might be relevant to the further development of CRC. These findings provide a potential contribution to the early prediction and interception of CRC occurrence.
Topics: Adenomatous Polyps; Adult; Aged; Bacteroides; Clostridiales; Colonic Polyps; Colorectal Neoplasms; Feces; Female; Fusobacterium; Gastrointestinal Microbiome; High-Throughput Nucleotide Sequencing; Humans; Klebsiella pneumoniae; Male; Middle Aged; Occult Blood; Prevotella
PubMed: 33233735
DOI: 10.3390/genes11111374 -
Antimicrobial Agents and Chemotherapy Nov 1999The activities of gemifloxacin (SB 265805, LB20304) and comparator agents were determined by an agar dilution method against 419 clinical strains of less-commonly... (Comparative Study)
Comparative Study
The activities of gemifloxacin (SB 265805, LB20304) and comparator agents were determined by an agar dilution method against 419 clinical strains of less-commonly identified species of anaerobes. Gemifloxacin was generally more active than trovafloxacin against gram-positive strains by one to two dilutions. Peptostreptococci (Peptostreptococcus asaccharolyticus, Peptostreptococcus magnus, Peptostreptococcus micros, and Peptostreptococcus prevotii) and Porphyromonas spp. (Porphyromonas asaccharolytica, Porphyromonas canoris, Porphyromonas gingivalis, and Porphyromonas macacae) were all susceptible to =0.25 microgram of gemifloxacin per ml. The MICs of gemifloxacin at which 90% of the following strains were inhibited (MIC(90)s) were =2 microgram/ml: Actinomyces israelii, Actinomyces odontolyticus, Clostridium innocuum, Clostridium clostridioforme, Anaerobiospirillum spp., Bacteroides tectum, Bacteroides ureolyticus, Bacteroides gracilis (now Campylobacter gracilis), Prevotella intermedia, Prevotella heparinolytica, and the Prevotella oris-buccae group. Fusobacterium naviforme and Fusobacterium necrophorum were also susceptible to =2 microgram of gemifloxacin per ml, while Fusobacterium varium strains exhibited a bimodal pattern; the other Fusobacterium species, such as Fusobacterium ulcerans and Fusobacterium russii, as well as Veillonella spp., the Prevotella melaninogenica group, Prevotella bivia, Clostridium difficile, and Bilophila wadsworthia were relatively resistant to gemifloxacin (MIC(90)s, >/=4 microgram/ml).
Topics: Anti-Infective Agents; Bacteria, Anaerobic; Bacterial Infections; Colony Count, Microbial; Fluoroquinolones; Gemifloxacin; Humans; Microbial Sensitivity Tests; Naphthyridines
PubMed: 10543754
DOI: 10.1128/AAC.43.11.2726 -
World Journal of Gastroenterology Oct 2014To examine whether commensal bacteria are a contributing cause of stress-related mucosal inflammation.
AIM
To examine whether commensal bacteria are a contributing cause of stress-related mucosal inflammation.
METHODS
Human peripheral blood monocyte-derived dendritic cells (MoDCs) were stimulated by commensal bacterial strains, including Escherichia coli, Clostridium clostridioforme, Bacteroides vulgatus (B. vulgatus), Fusobacterium varium (F. varium), and Lactobacillus delbrueckii subsp. bulgaricus. After incubation, corticotropin-releasing factor (CRF) and urocortin 1 (UCN1) mRNA in the cells was examined by real-time reverse transcription polymerase chain reaction. Supernatants from the cells were tested for CRF and UCN1 using an enzyme-linked immunosorbent assay.
RESULTS
Both CRF and UCN1 were significantly augmented by B. vulgatus and F. varium at both the mRNA and protein levels. In particular, B. vulgatus stimulated human MoDCs, resulting in extremely high levels of CRF and UCN1.
CONCLUSION
Stimulation of MoDCs by B. vulgatus and F. varium may be associated with CRF/UCN1-related intestinal disorders, such as irritable bowel syndrome and inflammatory bowel disease.
Topics: Adult; Corticotropin-Releasing Hormone; Dendritic Cells; Host-Pathogen Interactions; Humans; Intestines; Male; Middle Aged; Phenotype; RNA, Messenger; Symbiosis; Up-Regulation; Urocortins
PubMed: 25339828
DOI: 10.3748/wjg.v20.i39.14420 -
Infection and Immunity Jan 1976Intra-abdominal sepsis was studied in Wistar rats by using four microbial species: Escherichia coli, enterococci, Bacteroides fragilis, and Fusobacterium varium. These...
Intra-abdominal sepsis was studied in Wistar rats by using four microbial species: Escherichia coli, enterococci, Bacteroides fragilis, and Fusobacterium varium. These organisms were implanted into the peritoneal cavity singly and in all possible dual combinations. Results were evaluated by mortality rates and the incidence of intra-abdominal abscesses on autopsy following sacrifice after 7 days. Mortality was restricted to recipients of E. coli, thus implicating coliforms in the acute lethality associated with this experimental model. Intra-abdominal abscesses were produced in 61 of 95 (94%) animals that received the combination of an anaerobe and a facultative organism. Abscesses failed to form with any single strain or with E. coli plus enterococci, and they were detected in one 1 of 19 animals receiving B. fragilis plus F. varium. These results suggest that intra-abdominal abscess formation is related to synergy between anaerobes and facultative bacteria.
Topics: Abdomen; Abscess; Animals; Bacteroides fragilis; Enterococcus faecalis; Escherichia coli; Fusobacterium; Male; Rats
PubMed: 814099
DOI: 10.1128/iai.13.1.22-26.1976 -
Antimicrobial Agents and Chemotherapy Jan 2001The activity of ABT-773, a novel ketolide antibiotic, against clinical isolates of anaerobic bacteria was determined and compared to the activities of other... (Comparative Study)
Comparative Study
The activity of ABT-773, a novel ketolide antibiotic, against clinical isolates of anaerobic bacteria was determined and compared to the activities of other antimicrobial agents. MICs at which 90% of isolates were inhibited (MIC(90)s) were =0.06 microg/ml for Actinomyces spp., Clostridium perfringens, Peptostreptococcus spp., Propionibacterium spp., and Porphyromonas spp. The MIC(50)s and MIC(90)s were =0.06 and >32 microg/ml, respectively, for Eubacterium spp., Lactobacillus spp., Clostridium difficile, and Clostridium ramosum. The MIC(90) for Bilophila wadsworthia, Bacteroides ureolyticus, and Campylobacter gracilis was 1 microg/ml, and that for Prevotella bivia and other Prevotella spp. was 0.5 microg/ml. The MIC(90) for Fusobacterium nucleatum was 8 microg/ml, and that for Fusobacterium mortiferum and Fusobacterium varium was >32 microg/ml. The MIC(90)s for the Bacteroides fragilis group were as follows: for B. fragilis, 8 microg/ml; for Bacteroides thetaiotaomicron, Bacteroides ovatus, Bacteroides distasonis, and Bacteroides uniformis, >32 microg/ml; and for Bacteroides vulgatus, 4 microg/ml. Telithromycin MICs for the B. fragilis group were usually 1 to 2 dilutions higher than ABT-773 MICs. For all strains, ABT-773 was more active than erythromycin by 4 or more dilutions, and for some strains this drug was more active than clindamycin.
Topics: Anti-Bacterial Agents; Bacteria, Anaerobic; Bacterial Infections; Erythromycin; Humans; Ketolides; Microbial Sensitivity Tests
PubMed: 11120995
DOI: 10.1128/AAC.45.1.345-348.2001 -
Journal of Agricultural and Food... Sep 2020Interaction of tea phenolics with gut microbiota may play an integral role in the health benefits of these bioactive compounds, yet this interaction is not fully...
Interaction of tea phenolics with gut microbiota may play an integral role in the health benefits of these bioactive compounds, yet this interaction is not fully understood. Here, the metabolic fate of epigallocatechin-3-gallate (EGCG) and its impact on gut microbiota were integrally investigated fermentation. As revealed by ultrahigh performance liquid chromatography hybrid quadrupole Orbitrap mass spectrometry (UHPLC-Q-Orbitrap-MS), EGCG was promptly degraded into a series of metabolites, including 4-phenylbutyric acid, 3-(3',4'-dihydroxyphenyl)propionic acid, and 3-(4'-hydroxyphenyl)propionic acid, through consecutive ester hydrolysis, C-ring opening, A-ring fission, dehydroxylation, and aliphatic chain shortening. Microbiome profiling indicated that, compared to the blank, EGCG treatment resulted in stimulation of the beneficial bacteria , , and . Additionally, the pathogenic bacteria , , and were inhibited. Furthermore, changes in concentrations of metabolites, including 4-phenylbutyric acid and phenylacetic acid, were strongly correlated with changes in the abundance of specific gut microbiota. These reciprocal interactions between EGCG and gut microbiota may collectively contribute to the health benefits of EGCG.
Topics: Adult; Bacteria; Catechin; Female; Fermentation; Gastrointestinal Microbiome; Humans; Male; Mass Spectrometry; Propionates; Young Adult
PubMed: 32808768
DOI: 10.1021/acs.jafc.0c03587 -
Journal of Medical Microbiology May 2009Interleukin 2 (IL-2)- and IL-10-knockout mice develop spontaneous colitis under conventional but not germ-free conditions, suggesting that commensal bacteria play an...
Interleukin 2 (IL-2)- and IL-10-knockout mice develop spontaneous colitis under conventional but not germ-free conditions, suggesting that commensal bacteria play an important role in the pathogenesis of colitis. However, interactions between commensal bacteria and colonic epithelial cells have not been fully investigated. We therefore assessed the ability of various commensal bacteria and probiotics to adhere to and invade colonic epithelial cells. Effects of the bacteria on production of proinflammatory cytokines were also measured. Commensal bacteria, including mucosal organisms isolated from ulcerative colitis (UC) patients, such as Fusobacterium varium, reported as a possible pathogen in UC, Bacteroides vulgatus, Escherichia coli and Clostridium clostridioforme, as well as their type strains and probiotics, were assessed for their ability to adhere to and invade colonic epithelial cells using two cell lines, SW-480 and HT-29. Our experiments employed co-incubation, a combination of scanning and transmission electron microscopy and recovery of bacteria from infected-cell lysates. F. varium and several other commensal bacteria, but not probiotics, adhered to colonic epithelial cells and invaded their cytoplasm. ELISA and real-time PCR revealed that the host cells, particularly those invaded by F. varium, showed significant increases in IL-8 and TNF-alpha concentrations in supernatants, with elevation of IL-8, TNF-alpha, MCP-1 and IL-6 mRNAs. Furthermore, IL-8 and TNF-alpha expression and nuclear phosphorylated NF-kappaB p65 expression could be immunohistochemically confirmed in inflamed epithelium with cryptitis or crypt abscess in UC patients. Certain commensal bacteria can invade colonic epithelial cells, activating early intracellular signalling systems to trigger host inflammatory reactions.
Topics: Adenocarcinoma; Animals; Bacterial Adhesion; Cell Line, Tumor; Colitis, Ulcerative; Colon; Colonic Neoplasms; Cytokines; DNA Primers; Humans; Inflammation; Interleukin-10; Interleukin-2; Interleukin-8; Intestinal Mucosa; Mice; Mice, Knockout
PubMed: 19369513
DOI: 10.1099/jmm.0.005801-0 -
Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model.Applied and Environmental Microbiology Feb 2016The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions...
The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success.
Topics: Aerobiosis; Anaerobiosis; Animals; Cockroaches; Enterobacteriaceae; Fusobacterium; Gastrointestinal Microbiome; Gastrointestinal Tract; Germ-Free Life; Oxygen
PubMed: 26637604
DOI: 10.1128/AEM.03130-15