WorldWideScience

Sample records for bacteroides fragilis group

  1. Multidrug-resistant Bacteroides fragilis group on the rise in Europe?

    DEFF Research Database (Denmark)

    Hartmeyer, G N; Sóki, J; Nagy, E;

    2012-01-01

    We report a case of multidrug-resistance (MDR) in a strain of Bacteroides fragilis from a blood culture and abdominal fluid in a Danish patient. The patient had not been travelling for several years and had not received antibiotics prior to the present case. We also summarize the cases that have...... been reported to date of MDR B. fragilis group in Europe. As far as we know, a case like this with MDR B. fragilis has not been described in Scandinavia before....

  2. Spinal epidural abscess caused by Bacteroides fragilis group after dilation and curettage for incomplete abortion

    Directory of Open Access Journals (Sweden)

    Masaki Ohyagi

    2012-01-01

    Full Text Available Spinal epidural abscess (SEA is a rare infection complicated in patients who have some risk factors such as injection-drug use, diabetes mellitus, and several illnesses. However, no case of SEA associated with abortion has been reported. Here we report a case of SEA in a 30-year-old woman after dilation and curettage for incomplete abortion. The diagnosis of SEA was done by MRI and pus was drained after the cervical discectomy. Bacteroides fragilis group was cultured from the aspirated pus sample. The patient responded to surgical drainage and antibiotics.

  3. Spinal epidural abscess caused by bacteroides fragilis group after dilation and curettage for incomplete abortion.

    Science.gov (United States)

    Ohyagi, Masaki; Ohkubo, Takuya; Taniyama, Takashi; Tomizawa, Shoji; Okawa, Atsushi; Yokota, Takanori; Mizusawa, Hidehiro

    2012-04-01

    Spinal epidural abscess (SEA) is a rare infection complicated in patients who have some risk factors such as injection-drug use, diabetes mellitus, and several illnesses. However, no case of SEA associated with abortion has been reported. Here we report a case of SEA in a 30-year-old woman after dilation and curettage for incomplete abortion. The diagnosis of SEA was done by MRI and pus was drained after the cervical discectomy. Bacteroides fragilis group was cultured from the aspirated pus sample. The patient responded to surgical drainage and antibiotics.

  4. An assessment of Bacteroides fragilis group organisms as indicators of human faecal pollution.

    Science.gov (United States)

    Allsop, K; Stickler, D J

    1985-01-01

    Membrane filtration techniques were used to enumerate Bacteroides fragilis group (BFG) organisms and Escherichia coli in a variety of natural waters, the influents and effluents from three types of sewage treatment plants and faeces of various animals. The results suggest that BFG organisms die off more rapidly than E. coli in water and that animal faeces are not a significant source of BFG. It is suggested that the ratio of BFG to E. coli in water may be used to indicate the proximity of a source of human faecal contamination.

  5. The enumeration of Bacteroides fragilis group organisms from sewage and natural waters.

    Science.gov (United States)

    Allsop, K; Stickler, D J

    1984-02-01

    A membrane filtration technique has been developed for the enumeration of Bacteroides fragilis group (BFG) organisms from sewage and natural waters. The method uses the agar medium of Wilkins and Chalgren supplemented with gentamicin, penicillin, aesculin and ferric ammonium citrate. Membrane filters with 0.22 micron pores were significantly more efficient than those with 0.45 micron pores in the isolation of BFG. A preliminary incubation period of 4 h at 30 degrees C prior to 44 h at 37 degrees C yielded significantly higher numbers of BFG than direct incubation at 37 degrees C for 48 h.

  6. Effect of clavulanic acid on the activities of ten beta-lactam agents against members of the Bacteroides fragilis group.

    Science.gov (United States)

    Lamothe, F; Auger, F; Lacroix, J M

    1984-01-01

    Clavulanic acid reduced the MICs of amoxicillin, carbencillin , cefamandole, cefotaxime, ceftazidime, ceftizoxime, cephalothin, and penicillin G, but not of cefoxitin or moxalactam, against 77 isolates of the Bacteroides fragilis group, all rapidly beta-lactamase positive by the nitrocefin slide test. It had no effect on the susceptibilities of eight Bacteroides distasonis strains that were slowly beta-lactamase positive (18 h of incubation). PMID:6732233

  7. First national survey of antibiotic susceptibility of the Bacteroides fragilis group: emerging resistance to carbapenems in Argentina.

    Science.gov (United States)

    Fernández-Canigia, Liliana; Litterio, Mirta; Legaria, María C; Castello, Liliana; Predari, Silvia C; Di Martino, Ana; Rossetti, Adelaida; Rollet, Raquel; Carloni, Graciela; Bianchini, Hebe; Cejas, Daniela; Radice, Marcela; Gutkind, Gabriel

    2012-03-01

    The antibiotic susceptibility rates of 363 clinical Bacteroides fragilis group isolates collected from 17 centers in Argentina during the period from 2006 to 2009 were as follows: piperacillin-tazobactam, 99%; ampicillin-sulbactam, 92%; cefoxitin, 72%; tigecycline, 100%; moxifloxacin, 91%; and clindamycin, 52%. No metronidazole resistance was detected in these isolates during this time period. Resistance to imipenem, doripenem, and ertapenem was observed in 1.1%, 1.6%, and 2.3% of B. fragilis group strains, respectively. B. fragilis species showed a resistance profile of 1.5% to imipenem, 1.9% to doripenem, and 2.4% to ertapenem. This is the first report of carbapenem resistance in Argentina. The cfiA gene was present in 8 out of 23 isolates, all of them belonging to the B. fragilis species and displaying reduced susceptibility or resistance to carbapenems (MICs ≥ 4 μg/ml). Three out of eight cfiA-positive isolates were fully resistant to carbapenems, while 5 out of 8 isolates showed low-level resistance (MICs, 4 to 8 μg/ml). The inhibition by EDTA was a good predictor of the presence of metallo-β-lactamases in the fully resistant B. fragilis strains, but discrepant results were observed for low-level resistant isolates. B. fragilis was more susceptible to antimicrobial agents than other Bacteroides species. Bacteroides vulgatus species was the most resistant to ampicillin-sulbactam and piperacillin-tazobactam, and B. thetaiotaomicron/ovatus strains showed the highest level of resistance to carbapenems, with an unknown resistance mechanism. B. vulgatus and the uncommon non-Bacteroides fragilis species were the most resistant to moxifloxacin, showing an overall resistance rate of 15.1%.

  8. Heterogeneity in resistant fecal Bacteroides fragilis group collected from healthy people.

    Science.gov (United States)

    Narimani, T; Douraghi, M; Owlia, P; Rastegar, A; Esghaei, M; Nasr, B; Talebi, M

    2016-06-01

    Normal nonpathogenic flora would represent a constant lake of resistance genes potentially transferable to human pathogens. To assess the prevalence of resistance genes and genetic variability of Bacteroides fragilis group (BFG) from normal flora, 177 Bacteroides isolates obtained from the fecal samples of healthy individuals. These isolates were subjected to antibiotic susceptibility testing and pulsed field gel electrophoresis (PFGE). The isolates were further tested for the presence of ermF, tetQ and bft genes by PCR. Our results indicated the presence of different clonal strains (1 common type and 57 single types) among the resistant isolates. The resistance rate for the six antibiotics in this study was between 1% and 95%. Most of the isolates (99%) were susceptible to metronidazole. ermF and tetQ were detected in all erythromycin and tetracycline resistant isolates. None of the isolates were carried bft gene. These data suggest dissemination of heterogenic clonal groups in healthy persons and resistance to 5 high commonly used antibiotics.

  9. Evaluation of a direct fluorescent antibody staining method for rapid identification of members of the bacteroides fragilis group.

    Science.gov (United States)

    DeGirolami, P C; Mepani, C P

    1981-07-01

    A direct fluorescent antibody test kit (Fluorotec-F, Pfizer Inc., New York, New York) designed for rapid identification of members of the Bacteroides fragilis group (BFG) was evaluated. Tested were 228 clinical specimens (144 direct smears of clinical material, 14 smears of positive blood cultures, and 70 smears of colonies isolated from clinical material) and 49 reference strains of anaerobic bacteria, including 23 members of the BFG. Fluorotec-F detected 68 of 69 (98.5%) members of the BFG, including 55 B. fragilis, 12 B. thetaiotaomicron, and two B. ovatus, identified by cultural methods in all clinical specimens. Three specimens that yielded B. uniformis also fluoresced. Three specimens fluoresced but failed to yield members of the BFG or B. uniformis on culture. Of the 49 reference strains tested, all strains of B. fragilis, B. thetaiotaomicron, nd B. uniformis tested were detected by Fluorotec-F, but only five of a total of 14B. vulgatus, B. distasonis, and B. ovatus tested fluoresced. Of the 25 reference strains of anaerobic bacteria not belonging to the BFG, none fluoresced except for two strains of B. eggerthii. Direct fluorescent antibody staining of smears of clinical specimens suitable for anaerobic culture is a valuable tool for rapid detection of B. fragilis infections.

  10. Survey of antimicrobial susceptibility patterns of the bacteria of the Bacteroides fragilis group isolated from the intestinal tract of children

    Directory of Open Access Journals (Sweden)

    Viviane Nakano

    2004-05-01

    Full Text Available The bacteria of the Bacteroides fragilis group are considered important clinical pathogens and they are the most common anaerobes isolated from human endogenous infections. In this study, the susceptibility patterns to antibiotics and metals of 114 species of the B. fragilis group isolated from children with and without diarrhea were determined. Susceptibility was assayed by using an agar dilution method with Wilkins-Chalgren agar. All B. fragilis strains were resistant to lead and nickel, but susceptible to metronidazole and imipenem. beta-lactamase production was detected by using biological and nitrocefin methods, respectively, in 50% and 90.6% of the isolates of children with diarrhea and in 60% and 90% of the isolates of children without diarrhea. Our results show an increase of antibiotics and metals resistance in this microbial group, and a periodic evaluation of the antimicrobial susceptibility is needed. In Brazil, the contamination for antibiotics or metal ions is often observed, and it is suggested an increase the antimicrobial resistance surveillance of this microbial group, mainly those isolated from children's diarrhea.

  11. Update on resistance of Bacteroides fragilis group and related species with special attention to carbapenems 2006-2009.

    Science.gov (United States)

    Snydman, D R; Jacobus, N V; McDermott, L A; Golan, Y; Goldstein, E J C; Harrell, L; Jenkins, S; Newton, D; Pierson, C; Rosenblatt, J; Venezia, R; Gorbach, S L; Queenan, A M; Hecht, D W

    2011-08-01

    The susceptibility trends for the species of the Bacteroides fragilis group against various antibiotics were determined using data from 4 years [2006-2009] on 1957 isolates referred by 8 medical centers participating in a National Survey for the Susceptibility of B. fragilis. The antibiotic test panel included doripenem, ertapenem, imipenem, meropenem, ampicillin:sulbactam, piperacillin:tazobactam, cefoxitin, clindamycin, moxifloxacin, tigecycline, chloramphenicol and metronidazole. MICs were determined using agar dilution methods following CLSI recommendations. Genetic analysis of isolates from 2008 with elevated MICs (>2 μg/mL) to one or more of the carbapenems to detect presence of the cfiA gene was performed using PCR methodology. The results showed an increase in the resistance rates to the β-lactam antibiotics. High resistance rates were seen for clindamycin and moxifloxacin (as high as 60% for clindamycin and >80% for moxifloxacin), with relatively stable low resistance (5.4%) for tigecycline. For carbapenems, resistance in B. fragilis was 1.1%-2.5% in 2008-9. One isolate resistant to metronidazole (MIC 32 μg/mL) was observed as well as isolates with elevated MICs to chloramphenicol (16 μg/mL). Genetic analysis indicated that the cfiA gene was present in some but not all of the isolates with high MICs to the carbapenems. These data indicate that there continue to be changes in susceptibility over time, and that resistance can be seen among the carbapenems. High antibiotic resistance rates tend to be associated with specific species.

  12. [Use of reactions with Limulus amoebocyte lysate (LAL) to determine biological activity of lipopolysaccharides from reference and clinical strains of the Bacteroides fragilis group].

    Science.gov (United States)

    Rokosz, Alicja; Fiejka, Maria; Górska, Paulina; Aleksandrowicz, Janina; Meisel-Mikołajczyk, Felicja; Łuczak, MirosŁaw

    2002-01-01

    The aim of this study was to determine and compare a biological activity of lipopolysaccharides (LPS) from reference and clinical strains of strictly anaerobic bacteria belonging to the Bacteroides fragilis group (BFG) by means of quantitative, photometric BET (LAL) method with Limulus polyphemus amoebocyte lysate and chromogenic substrate S-2423. Lipopolysaccharides of five BFG species were extracted by Westphal and Jann method (1965) from eight reference and two clinical strains of B. fragilis group. Crude LPS preparations were purified according to the procedure described by Gmeiner (1975) with ultracentrifugation and nuclease treatment. Biological activities of bacterial endotoxins were determined by quantitative BET method with chromogenic substrate S-2423 (ENDOCHROME kit, Charles River Endosafe Ltd., USA). Tests were performed according to the producer's recommendations. E. coli O55:B5 LPS was applied to compare its activity in reaction with LAL reagent with activities of LPS preparations from rods of the Bacteroides genus. Among examined bacterial compounds the most active in BET method was E. coli O55:B5 LPS. Activities of lipopolysaccharides from five species of BFG rods in reaction with Limulus amoebocyte lysate were differentiated. Greater ability to activate LAL proenzyme revealed lipopolysaccharides of these species of the Bacteroides genus, which are important from the clinical point of view--B. fragilis and B. thetaiotaomicron.

  13. [Selected properties of Bacteroides fragilis enterotoxigenic strains].

    Science.gov (United States)

    Rokosz, A; Meisel-Mikołajczyk, F

    1995-01-01

    Seven B. fragilis strains were examined. One strain was reference, non-enterotoxigenic, representing serotype E2 according to Beerens et al. (1971). Six strains produced enterotoxin (ETBF). Four of them were isolated from human feces and two of them from swine feces. All strains were investigated morphologically, biochemically (ATB Expression, France) and by means of direct immunofluorescence (Bacteroides--IF test, Poland). Their resistance to chemotherapeutics was tested (ATB Expression, France). The MIC values of clindamycin and metronidazole were determined using E test strips (AB Biodisk, Sweden). Each strain formed capsules. The percentage of encapsulated cells was high (80-100%). Some strains produced thick capsules. Biochemical patterns were similar and typical for B. fragilis rods. One enterotoxigenic strain produced gelatinase and three ETBF strains fermented trehalose. All strains reacted in direct immunofluorescence exclusively with conjugate against serotype E of BFG. Thus, each strain showed antigenic pattern E. Drug susceptibility of all strains was similar. One enterotoxigenic strain was resistant to clindamycin. All strains were susceptible to metronidazole. These studies indicate that on the basis of morphological, biochemical and serological features (IF), enterotoxigenic B. fragilis strains cannot be distinguished from the nonenterotoxigenic one. Also, the correlation between toxigenicity and drug sensitivity of the examined strains is not observed.

  14. Detection of Bacteroides fragilis endotoxin in amniotic fluid by counterimmunoelectrophoresis

    NARCIS (Netherlands)

    I. Beckmann (Ilse); K. de Graaff (K.); F. Meisel-Mikolajczyk; H.C.S. Wallenburg (Henk)

    1994-01-01

    textabstractThe ability of counter immunoelectrophoresis (CIE) to detectBacteroides fragilis endotoxin in amniotic fluid in small concentrations was evaluated. A method was developed which, in combination with ultrafiltration, permits detection ofB. fragilis endotoxin in amniotic fluid in a concentr

  15. Chromosomal DNA probes for the identification of Bacteroides tectum and Bacteroides fragilis from the oral cavity of cats.

    Science.gov (United States)

    Love, D N; Bailey, G D

    1993-01-01

    A dot-blot hybridisation assay using high molecular weight DNA as whole chromosomal probes was used to differentiate Bacteroides tectum from Bacteroides fragilis. 32P-labelled probes were compared with digoxigenin (DIG)-labelled probes. The whole chromosomal probes were specific--differentiating B. tectum from B. fragilis and both from a variety of other species (including other members of the genera Bacteroides, Fusobacterium, Eubacterium, and Prevotella) found in normal and abnormal mouths of cats and horses. However, even at very high stringencies, B. tectum homology groups I, II and III were not distinguishable from one another using either 32P-labelled or DIG-labelled probes. Thus, DIG-labelled whole chromosome probes directed against cellular DNA released directly onto nitrocellulose membranes is considered a useful method for diagnostic veterinary laboratories wishing to identify B. tectum and distinguish it from B. fragilis and other oral anaerobic flora of cats.

  16. Distribution, Detection of Enterotoxigenic Strains and Antimicrobial Drug Susceptibility Patterns of Bacteroides Fragilis Group in Diarrheic and Non-Diarrheic Feces from Brazilian Infants

    Science.gov (United States)

    Ferreira, Débora Paula; Silva, Vânia Lúcia; Guimarães, Danielle Aparecida; Coelho, Cíntia Marques; Zauli, Danielle Alves Gomes; Farias, Luiz Macêdo; Carvalho, Maria Auxiliadora Roque; Diniz, Claudio Galuppo

    2010-01-01

    Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0–5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic), and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children. PMID:24031535

  17. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of bacteroides fragilis group in diarrheic and non-diarrheic feces from brazilian infants.

    Science.gov (United States)

    Ferreira, Débora Paula; Silva, Vânia Lúcia; Guimarães, Danielle Aparecida; Coelho, Cíntia Marques; Zauli, Danielle Alves Gomes; Farias, Luiz Macêdo; Carvalho, Maria Auxiliadora Roque; Diniz, Claudio Galuppo

    2010-07-01

    Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic), and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

  18. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

    Directory of Open Access Journals (Sweden)

    Débora Paula Ferreira

    2010-10-01

    Full Text Available Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110 and non-diarrheic (n=65 fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic, and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

  19. [Possible role of enterotoxigenic Bacteroides fragilis in the etiology of infectious vaginitis].

    Science.gov (United States)

    Polanco, Nina; Manzi, Lorna; Carmona, Oswaldo

    2012-03-01

    Vaginitis is a common gynecologic disorder. It is due to several causes, some even unknown. Bacteroides fragilis is the most important anaerobe in clinical bacteriology, some strains of this group are notable for being enterotoxigenic and they have been associated with intestinal and extraintestinal syndromes. They have recently been isolated from patients with vaginitis. The purpose of this study was to investigate a possible association of enterotoxigenic B. fragilis with infectious vaginitis. 265 samples of vaginal exudate were processed, 202 from symptomatic patients and 63 healthy women. The identification of the microorganisms was carried out by conventional methods. In 31.2% of symptomatic patients were identified: Gardnerella vaginalis, Mobiluncus, Candida albicans, Mycoplasma hominis, Ureaplasma urealyticum and Streptococcus agalactiae. B. fragilis was identified in 27 symptomatic patients and 5 healthy women. These strains were cultivated in liquid medium and incubated during 48 h at 36 degrees C in anaerobe chambers. Supernatant activity was assayed in HT-29 cells. Eighteen B. fragilis strains isolated from symptomatic patients were enterotoxigenic, because induced alterations in target cell morphology. It was not identified in healthy women (P < 0.05). 77.7% of enterotoxigenic B. fragilis strains were not associated with other specific pathogens. This fact suggests that enterotoxigenic B. fragilis could be a cause for vaginitis. The effect of enterotoxin on E-cadherin of vaginal epithelium could facilitate invasion and its possible pathogenic role in the vagina. This is the first report that associates enterotoxigenic Bacteroides fragilis as a possible cause of infectious vaginitis.

  20. Early intestinal Bacteroides fragilis colonisation and development of asthma

    Directory of Open Access Journals (Sweden)

    Goossens Herman

    2008-09-01

    Full Text Available Abstract Background The 'hygiene hypothesis' suggests that early exposure to microbes can be protective against atopic disease. The intestinal microbial flora could operate as an important postnatal regulator of the Th1/Th2 balance. The aim of the study was to investigate the association between early intestinal colonisation and the development of asthma in the first 3 years of life. Methods In a prospective birth cohort, 117 children were classified according to the Asthma Predictive Index. A positive index included wheezing during the first three years of life combined with eczema in the child in the first years of life or with a parental history of asthma. A faecal sample was taken at the age of 3 weeks and cultured on selective media. Results Asthma Predictive Index was positive in 26/117 (22% of the children. The prevalence of colonisation with Bacteroides fragilis was higher at 3 weeks in index+ compared to index- children (64% vs. 34% p Bacteroides fragilis and Total Anaerobes counts at 3 weeks were significantly higher in children with a positive index as compared with those without. After adjusting for confounders a positive association was found between Bacteroides fragilis colonisation and Asthma Predictive Index (odds ratio: 4,4; confidence interval: 1,7 – 11,8. Conclusion Bacteroides fragilis colonisation at age 3 weeks is an early indicator of possible asthma later in life. This study could provide the means for more accurate targeting of treatment and prevention and thus more effective and better controlled modulation of the microbial milieu.

  1. Exploratory investigation of Bacteroides fragilis transcriptional response during in vitro exposure to subinhibitory concentration of metronidazole

    Directory of Open Access Journals (Sweden)

    Michele Cristine Ribeiro Freitas

    2016-09-01

    Full Text Available Bacteroides fragilis, member from commensal gut microbiota, is an important pathogen associated to endogenous infections and metronidazole remains a valuable antibiotic for the treatment of these infections, although bacterial resistance is widely reported. Considering the need of a better understanding on the global mechanisms by which B. fragilis survive upon metronidazole exposure, we performed a RNA-seq transcriptomic approach with validation of gene expression results by qPCR. Bacteria strains were selected after in vitro subcultures with subinhibitory concentration (SIC of the drug. From a wild type B. fragilis ATCC 43859 four derivative strains were selected: 1st and 4th subcultures under metronidazole exposure and 1st and 4th subcultures after drug removal. According to global gene expression analysis, 2,146 protein coding genes were identified, of which a total of 1,618 (77% were assigned to a Gene Ontology term (GO, indicating that most known cellular functions were taken. Among these 2,146 protein coding genes, 377 were shared among all strains, suggesting that they are critical for B. fragilis survival. In order to identify distinct expression patterns, we also performed a K-means clustering analysis set to 15 groups. This analysis allowed us to detect the major activated or repressed genes encoding for enzymes which act in several metabolic pathways involved in metronidazole response such as drug activation, defense mechanisms against superoxide ions, high expression level of multidrug efflux pumps, and DNA repair. The strains collected after metronidazole removal were functionally more similar to those cultured under drug pressure, reinforcing that drug-exposure lead to drastic persistent changes in the B. fragilis gene expression patterns. These results may help to elucidate B. fragilis response during metronidazole exposure, mainly at SIC, contributing with information about bacterial survival strategies under stress conditions

  2. Exploratory Investigation of Bacteroides fragilis Transcriptional Response during In vitro Exposure to Subinhibitory Concentration of Metronidazole

    Science.gov (United States)

    de Freitas, Michele C. R.; Resende, Juliana A.; Ferreira-Machado, Alessandra B.; Saji, Guadalupe D. R. Q.; de Vasconcelos, Ana T. R.; da Silva, Vânia L.; Nicolás, Marisa F.; Diniz, Cláudio G.

    2016-01-01

    Bacteroides fragilis, member from commensal gut microbiota, is an important pathogen associated to endogenous infections and metronidazole remains a valuable antibiotic for the treatment of these infections, although bacterial resistance is widely reported. Considering the need of a better understanding on the global mechanisms by which B. fragilis survive upon metronidazole exposure, we performed a RNA-seq transcriptomic approach with validation of gene expression results by qPCR. Bacteria strains were selected after in vitro subcultures with subinhibitory concentration (SIC) of the drug. From a wild type B. fragilis ATCC 43859 four derivative strains were selected: first and fourth subcultures under metronidazole exposure and first and fourth subcultures after drug removal. According to global gene expression analysis, 2,146 protein coding genes were identified, of which a total of 1,618 (77%) were assigned to a Gene Ontology term (GO), indicating that most known cellular functions were taken. Among these 2,146 protein coding genes, 377 were shared among all strains, suggesting that they are critical for B. fragilis survival. In order to identify distinct expression patterns, we also performed a K-means clustering analysis set to 15 groups. This analysis allowed us to detect the major activated or repressed genes encoding for enzymes which act in several metabolic pathways involved in metronidazole response such as drug activation, defense mechanisms against superoxide ions, high expression level of multidrug efflux pumps, and DNA repair. The strains collected after metronidazole removal were functionally more similar to those cultured under drug pressure, reinforcing that drug-exposure lead to drastic persistent changes in the B. fragilis gene expression patterns. These results may help to elucidate B. fragilis response during metronidazole exposure, mainly at SIC, contributing with information about bacterial survival strategies under stress conditions in their

  3. [Tigecycline: CMI 50/90 towards 1766 Gram-negative bacilli (3rd generation cephalosporins resistant enterobacteriaceae), Acinetobacter baumannii and Bacteroides fragilis group, University Hospital - Montpellier, 2008-2011].

    Science.gov (United States)

    Froment Gomis, P; Jean-Pierre, H; Rousseau-Didelot, M-N; Compan, B; Michon, A-L; Godreuil, S

    2013-12-01

    Tigecycline is a new glycylcyclin with a wide spectre including multi-resistant bacteria. Our laboratory tests in routine the in vitro activity of the TGC towards clinically significant isolates of 3rd generation cephalosporins resistant enterobacteriaceae (EC3R), Acinetobacter baumannii and Bacteroides fragilis group (BFG). The objective of this study is to describe the in vitro activity of TGC against these strains isolated between 2008 and 2011 in the university hospital of Montpellier. In this study period, 1070 isolates EC3R including 541 extended spectrum β-lactamase-producers (ESBL) strains, 47 isolates of A. baumannii including 40 multi-resistant isolates and 645 isolates of BFG were tested. Minimum inhibitory concentrations (MIC) were determined using the E-test method. TGC was active against 86.2% of EC3R with a MIC 90 less or equal to 1mg/L (Escherichia coli being the most sensitive species). A. baumannii and BFG were also inhibited at low concentrations of TGC with a MIC 90 less or equal to 2mg/L respectively for 47% and 84.2% of the isolates. Our study confirms the activity of TGC against the EC3R including ESBL-producers strains. The relevance of the therapeutic use of TGC on the BFG isolates with a MIC greater than 2mg/L should be better documented. Often prescribed in therapeutic impasse, the proper use of TGC would require: clarifying the threshold of sensitivity for some species (i.e., A. baumannii, Bacteroides fragilis group); a better understanding of correlation between in vitro and in vivo activity.

  4. Absence of Porphyromonas asaccharolytica, Bacteroides fragilis and Chlamydia pneumoniae in human subgingival plaque.

    Science.gov (United States)

    Tran, T; Flynn, M J; Chen, C; Slots, J

    1997-12-01

    Little is known about the presence of common medical pathogens in the human oral cavity. Using a 16S rRNA-based PCR identification method, this study determined the occurrence of Porphyromonas asaccharolytica, Bacteroides fragilis and Chlamydia pneumoniae in subgingival plaque from 50 adults with advanced periodontitis. Each patient contributed samples from 3 deep periodontal pockets collected by paper points. The PCR primers were for P. asaccharolytica 5'-CTC TAG CTA GAG TGT ACT GG-3' and 5'-ATA GGG TTT ATA GAT TAG CTC TCT-3', for B. fragilis 5'-AAT GAT TCC GCA TGG TTT CAT TA-3' and 5'-GCG GTG ATT GCT CAC TGA CA-3', and for C. pneumoniae 5'- TGA CAA CTG TAG AAA TAC AGC-3' and 5'-CGC CTC TCT CCT ATA AAT-3'. The primers yielded a single amplicon with the respective reference strains and produced no amplicon with colonies of 25 groups of oral organisms. None of the three test species were detected in any of the 50 pooled subgingival samples tested. P. asaccharyolytica, B. fragilis and C. pneumoniae do not seem to be part of the periodontopathic microbiota in humans.

  5. Augmentation of the in vitro activity of azlocillin against Bacteroides fragilis by clavulanic acid.

    Science.gov (United States)

    Bansal, M B; Chuah, S K; Thadepalli, H

    1984-01-01

    Azlocillin was active against 90% of 154 strains of Bacteroides fragilis at a concentration of 64 micrograms/ml. Twenty-eight strains of B. fragilis with an azlocillin MIC of greater than or equal to 8 micrograms/ml were retested with a combination of azlocillin plus clavulanic acid. Of these strains, 71% showed a 4- to 32-fold decrease in the MIC of azlocillin plus clavulanic acid. PMID:6517552

  6. Bacteroides fragilis in biopsies of patients with major abscesses and diabetic foot infections: direct molecular versus culture-based detection

    OpenAIRE

    Stappers, Mark H. T.; Hagen, Ferry; Reimnitz, Peter; Mouton, Johan W.; Meis, Jacques F.; Gyssens, Inge C

    2016-01-01

    Direct determination by pathogen-specific real-time PCR assay for Bacteroides fragilis was compared to culture in major abscess and diabetic foot infection biopsy samples. Real-time PCR resulted in an increased detection rate of 12% for B. fragilis and could improve the detection of B. fragilis in clinical samples. (C) 2016 Elsevier Inc. All rights reserved.

  7. Comparative antimicrobial efficacy of Metapex, Metronidazole, BioPure MTAD, Aztreonam on Bacteroides fragilis and Propionibacterium acne

    Directory of Open Access Journals (Sweden)

    Rajkumar Balakrishnan

    2013-01-01

    Full Text Available Aim: The purpose of this study was to evaluate the comparative antibacterial efficacy of Biopure MTAD, Metapex, Metronidazole, and Aztreonam against two obligate anerobic bacteria. Materials and Methods: Antimicrobial efficacy of selected medicaments against two obligate anaerobic bacteria Bacteroides fragilis and Propionibacterium acnes was done by Agar disc-diffusion method. Pre-sterilized Whatman paper discs, 6 mm in diameter and soaked with the test solution, were prepared and placed onto the previously seeded agar Petri plates. Each plate was incubated in anaerobic jar for anerobic environment at 37°C for 48 hours. A zone of inhibition was recorded for each plate and the results were analysed statistically. Saline and ethanol used as control group in this study. Results: Biopure MTAD, Metapex and Metronidazole were effective against all the selected microorganisms. Aztreonam was effective against Bacteroides fragilis. Saline and ethanol used as control were ineffective. Conclusions: Metronidazole showed the superior antibacterial property amongst the tested medicaments.

  8. Bacteroides fragilis induce necrosis on mice peritoneal macrophages: In vitro and in vivo assays

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, J.M.B.D., E-mail: jmanya@terra.com.br [Laboratorio de Tecnologia em Cultura de Celulas, UEZO, Rio de Janeiro (Brazil); Laboratorio de Biologia de Anaerobios, IMPPG, UFRJ, Rio de Janeiro (Brazil); Seabra, S.H. [Laboratorio de Tecnologia em Cultura de Celulas, UEZO, Rio de Janeiro (Brazil); Vallim, D.C. [Instituto Oswaldo Cruz, Rio de Janeiro (Brazil); Americo, M.A.; Fracallanza, S.E.L. [Laboratorio de Bacteriologia Medica, IMPPG, UFRJ, Rio de Janeiro (Brazil); Vommaro, R.C. [Laboratorio de Ultra-estrutura Celular Hertha Meyer, IBCCF, UFRJ (Brazil); Domingues, R.M.C.P. [Laboratorio de Biologia de Anaerobios, IMPPG, UFRJ, Rio de Janeiro (Brazil)

    2009-10-02

    Bacteroides fragilis is an anaerobic bacteria component of human intestinal microbiota and agent of infections. In the host B. fragilis interacts with macrophages, which produces toxic radicals like NO. The interaction of activated mice peritoneal macrophages with four strains of B. fragilis was evaluated on this study. Previously was shown that such strains could cause metabolic and morphologic alterations related to macrophage death. In this work propidium iodide staining showed the strains inducing macrophage necrosis in that the labeling was evident. Besides nitroblue tetrazolium test showed that B. fragilis stimulates macrophage to produce oxygen radicals. In vivo assays performed in BalbC mice have results similar to those for in vitro tests as well as scanning electron microscopy, which showed the same surface pore-like structures observed in vitro before. The results revealed that B. fragilis strains studied lead to macrophage death by a process similar to necrosis.

  9. Genome sequence of the Bacteroides fragilis phage ATCC 51477-B1

    Science.gov (United States)

    Hawkins, Shawn A; Layton, Alice C; Ripp, Steven; Williams, Dan; Sayler, Gary S

    2008-01-01

    The genome of a fecal pollution indicator phage, Bacteroides fragilis ATCC 51477-B1, was sequenced and consisted of 44,929 bases with a G+C content of 38.7%. Forty-six putative open reading frames were identified and genes were organized into functional clusters for host specificity, lysis, replication and regulation, and packaging and structural proteins. PMID:18710568

  10. Multidrug-Resistant Bacteroides fragilis Bacteremia in a US Resident: An Emerging Challenge

    Directory of Open Access Journals (Sweden)

    Cristian Merchan

    2016-01-01

    Full Text Available We describe a case of Bacteroides fragilis bacteremia associated with paraspinal and psoas abscesses in the United States. Resistance to b-lactam/b-lactamase inhibitors, carbapenems, and metronidazole was encountered despite having a recent travel history to India as the only possible risk factor for multidrug resistance. Microbiological cure was achieved with linezolid, moxifloxacin, and cefoxitin.

  11. Production of a Mouse Antiserum to Bacteroides fragilis Enterotoxin Using a Recombinant Enterotoxin Precursor

    OpenAIRE

    Sandini, Silvia; d'Abusco, Anna Scotto; La Valle, Roberto; Pantosti, Annalisa

    2001-01-01

    The precursor of the Bacteroides fragilis metalloprotease enterotoxin was cloned and expressed in Escherichia coli, which was not able to process the precursor into the biologically active enterotoxin. Mouse antiserum elicited to the recombinant precursor reacted with the purified enterotoxin and with a crude enterotoxin preparation from an enterotoxigenic strain. The antiserum neutralized the cytotoxic activity of the enterotoxin in HT-29 cells.

  12. Novel Approach for Evaluation of Bacteroides fragilis Protective Role against Bartonella henselae Liver Damage in Immunocompromised Murine Model

    Science.gov (United States)

    Pagliuca, Chiara; Cicatiello, Annunziata G.; Colicchio, Roberta; Greco, Adelaide; Cerciello, Raimondo; Auletta, Luigi; Albanese, Sandra; Scaglione, Elena; Pagliarulo, Caterina; Pastore, Gabiria; Mansueto, Gelsomina; Brunetti, Arturo; Avallone, Bice; Salvatore, Paola

    2016-01-01

    Bartonella henselae is a gram-negative facultative intracellular bacterium and is the causative agent of cat-scratch disease. Our previous data have established that Bacteroides fragilis colonization is able to prevent B. henselae damages through the polysaccharide A (PSA) in an experimental murine model. In order to determine whether the PSA is essential for the protection against pathogenic effects of B. henselae in immunocompromised hosts, SCID mice were co-infected with B. fragilis wild type or its mutant B. fragilis ΔPSA and the effects of infection on murine tissues have been observed by High-Frequency Ultrasound (HFUS), histopathological examination, and Transmission Electron Microscopy (TEM). For the first time, echostructure, hepatic lobes length, vascular alterations, and indirect signs of hepatic dysfunctions, routinely used as signs of disease in humans, have been analyzed in an immunocompromised murine model. Our findings showed echostructural alterations in all infected mice compared with the Phosphate Buffer Solution (PBS) control group; further, those infected with B. henselae and co-infected with B. henselae/B. fragilis ΔPSA presented the major echostructural alterations. Half of the mice infected with B. henselae and all those co-infected with B. henselae/B. fragilis ΔPSA have showed an altered hepatic echogenicity compared with the renal cortex. The echogenicity score of co-infected mice with B. henselae/B. fragilis ΔPSA differed significantly compared with the PBS control group (p < 0.05). Moreover the inflammation score of the histopathological evaluation was fairly concordant with ultrasound findings. Ultrastructural analysis performed by TEM revealed no significant alterations in liver samples of SCID mice infected with B. fragilis wild type while those infected with B. fragilis ΔPSA showed the presence of collagen around the main vessels compared with the PBS control group. The liver samples of mice infected with B. henselae showed

  13. Population structure and distribution of virulence-related genes of Bacteroides fragilis isolates from Korea and Japan.

    Science.gov (United States)

    Ko, Kwan Soo; Kuwahara, Tomomi; Lee, Kyungwon; Kook, Yoon-Hoh

    2009-07-01

    Sequences for rpoB, gyrB, pdiA, and ompA were determined from 63 Bacteroides fragilis isolates, which were from Korea and Japan and include 4 reference strains. All 4 gene sequences supported clear separation of the cfi(+) group from the cfi(-) group. Combined sequences of the 60 division I isolates (cfi(-)) produced 45 different clones. Apparent discordance of gene trees, index of association, maximum likelihood test, and homoplasy ratio all supported a high frequency of recombination. There was no association between the presence of virulence-related genes and phylogenetic clustering in any gene tree.

  14. Genome sequence of the Bacteroides fragilis phage ATCC 51477-B1

    Directory of Open Access Journals (Sweden)

    Hawkins Shawn A

    2008-08-01

    Full Text Available Abstract The genome of a fecal pollution indicator phage, Bacteroides fragilis ATCC 51477-B1, was sequenced and consisted of 44,929 bases with a G+C content of 38.7%. Forty-six putative open reading frames were identified and genes were organized into functional clusters for host specificity, lysis, replication and regulation, and packaging and structural proteins.

  15. Oxygen-independent killing of Bacteroides fragilis by granule extracts from human polymorphonuclear leukocytes.

    OpenAIRE

    Wetherall, B L; Pruul, H; McDonald, P J

    1984-01-01

    Granule proteins from human neutrophils were prepared by extraction with acetate, and their antibacterial activity against Bacteroides fragilis was determined. Activity was highly dependent on pH; greatest killing occurred at the most acid pH tested (pH 5.0). Optimum activity was observed at physiological ionic strength and low bacterial numbers. Killing was inhibited by incubation temperatures of less than 37 degrees C. Eight times more extract was required to kill 50% of stationary-phase ba...

  16. A novel strain of Bacteroides fragilis enhances phagocytosis and polarises M1 macrophages

    Science.gov (United States)

    Deng, Huimin; Li, Zhengchao; Tan, Yafang; Guo, Zhaobiao; Liu, Yangyang; Wang, Ye; Yuan, Yuan; Yang, Ruifu; Bi, Yujing; Bai, Yang; Zhi, Fachao

    2016-01-01

    Commensal Bacteroides fragilis possesses immune-regulatory characteristics. Consequently, it has been proposed as a potential novel probiotic because of its therapeutic effects on immune imbalance, mental disorders and inflammatory diseases. Macrophages play a central role in the immune response, developing either a classical-M1 or an alternative-M2 phenotype after stimulation with various signals. The interactions between macrophages and B. fragilis, however, remain to be defined. Here, a new isolate of B. fragilis, ZY-312, was shown to possess admirable properties, including tolerance to simulated gastric fluid, intestinal fluid and ox bile, and good safety (MOI = 100, 200) and adherent ability (MOI = 100) to LoVo cells. Isolate ZY-312 cell lysate promoted phagocytosis of fluorescent microspheres and pathogenic bacteria in bone marrow-derived macrophage (BMDM) cells. Gene expression of IL-12, iNOS and IL-1β in BMDM cells was increased after treatment with ZY-312, indicating the induction of M1 macrophages, consistent with enhanced secretion of NO. Cell surface expression of CD80 and CD86 was also increased. This study is the first to demonstrate that B. fragilis enhances the phagocytic functions of macrophages, polarising them to an M1 phenotype. Our findings provide insight into the close relationship between B. fragilis and the innate immune system. PMID:27381366

  17. Structural and functional diversity of metalloproteinases encoded by the Bacteroides fragilis pathogenicity island.

    Science.gov (United States)

    Shiryaev, Sergey A; Aleshin, Alexander E; Muranaka, Norihito; Kukreja, Muskan; Routenberg, David A; Remacle, Albert G; Liddington, Robert C; Cieplak, Piotr; Kozlov, Igor A; Strongin, Alex Y

    2014-06-01

    Bacteroides fragilis causes the majority of anaerobic infections in humans. The presence of a pathogenicity island in the genome discriminates pathogenic and commensal B. fragilis strains. The island encodes metalloproteinase II (MPII), a potential virulence protein, and one of three homologous fragilysin isozymes (FRA; also termed B. fragilis toxin or BFT). Here, we report biochemical data on the structural-functional characteristics of the B. fragilis pathogenicity island proteases by reporting the crystal structure of MPII at 2.13 Å resolution, combined with detailed characterization of the cleavage preferences of MPII and FRA3 (as a representative of the FRA isoforms), identified using a high-throughput peptide cleavage assay with 18 583 substrate peptides. We suggest that the evolution of the MPII catalytic domain can be traced to human and archaebacterial proteinases, whereas the prodomain fold is a feature specific to MPII and FRA. We conclude that the catalytic domain of both MPII and FRA3 evolved differently relative to the prodomain, and that the prodomain evolved specifically to fit the B. fragilis pathogenicity. Overall, our data provide insights into the evolution of cleavage specificity and activation mechanisms in the virulent metalloproteinases.

  18. The dissemination of C10 cysteine protease genes in Bacteroides fragilis by mobile genetic elements

    LENUS (Irish Health Repository)

    Thornton, Roibeard F

    2010-04-23

    Abstract Background The C10 family of cysteine proteases includes enzymes that contribute to the virulence of bacterial pathogens, such as SpeB in Streptococcus pyogenes. The presence of homologues of cysteine protease genes in human commensal organisms has not been examined. Bacteroides fragilis is a member of the dominant Bacteroidetes phylum of the human intestinal microbiota, and is a significant opportunistic pathogen. Results Four homologues of the streptococcal virulence factor SpeB were identified in the B. fragilis genome. These four protease genes, two were directly contiguous to open reading frames predicted to encode staphostatin-like inhibitors, with which the protease genes were co-transcribed. Two of these protease genes are unique to B. fragilis 638R and are associated with two large genomic insertions. Gene annotation indicated that one of these insertions was a conjugative Tn-like element and the other was a prophage-like element, which was shown to be capable of excision. Homologues of the B. fragilis C10 protease genes were present in a panel of clinical isolates, and in DNA extracted from normal human faecal microbiota. Conclusions This study suggests a mechanism for the evolution and dissemination of an important class of protease in major members of the normal human microbiota.

  19. Enterotoxigenic and non-enterotoxigenic Bacteroides fragilis from fecal microbiota of children

    Directory of Open Access Journals (Sweden)

    Aline Ignacio

    2015-01-01

    Full Text Available Enterotoxigenic Bacteroides fragilis (ETBF is an important part of the human and animal intestinal microbiota and is commonly associated with diarrhea. ETBF strains produce an enterotoxin encoded by the bft gene located in the B. fragilispathogenicity island (BfPAI. Non-enterotoxigenic B. fragilis(NTBF strains lack the BfPAI and usually show two different genetic patterns, II and III, based on the absence or presence of a BfPAI-flanking region, respectively. The incidence of ETBF and NTBF strains in fecal samples isolated from children without acute diarrhea or any other intestinal disorders was determined. All 84 fecal samples evaluated were B. fragilis-positive by PCR, four of them harbored the bft gene, 27 contained the NTBF pattern III DNA sequence, and 52 were considered to be NTBF pattern II samples. One sample was positive for both ETBF and NTBF pattern III DNA sequences. All 19 B. fragilis strains isolated by the culture method were bft-negative, 9 belonged to pattern III and 10 to pattern II. We present an updated overview of the ETBF and NTBF incidence in the fecal microbiota of children from Sao Paulo City, Brazil.

  20. The dissemination of C10 cysteine protease genes in Bacteroides fragilis by mobile genetic elements

    Directory of Open Access Journals (Sweden)

    Kagawa Todd F

    2010-04-01

    Full Text Available Abstract Background The C10 family of cysteine proteases includes enzymes that contribute to the virulence of bacterial pathogens, such as SpeB in Streptococcus pyogenes. The presence of homologues of cysteine protease genes in human commensal organisms has not been examined. Bacteroides fragilis is a member of the dominant Bacteroidetes phylum of the human intestinal microbiota, and is a significant opportunistic pathogen. Results Four homologues of the streptococcal virulence factor SpeB were identified in the B. fragilis genome. These four protease genes, two were directly contiguous to open reading frames predicted to encode staphostatin-like inhibitors, with which the protease genes were co-transcribed. Two of these protease genes are unique to B. fragilis 638R and are associated with two large genomic insertions. Gene annotation indicated that one of these insertions was a conjugative Tn-like element and the other was a prophage-like element, which was shown to be capable of excision. Homologues of the B. fragilis C10 protease genes were present in a panel of clinical isolates, and in DNA extracted from normal human faecal microbiota. Conclusions This study suggests a mechanism for the evolution and dissemination of an important class of protease in major members of the normal human microbiota.

  1. Differential proteomic analysis of outer membrane enriched extracts of Bacteroides fragilis grown under bile salts stress.

    Science.gov (United States)

    Boente, Renata F; Pauer, Heidi; Silva, Deborah N S; Filho, Joaquim Santos; Sandim, Vanessa; Antunes, Luis Caetano M; Ferreira, Rosana Barreto Rocha; Zingali, Russolina B; Domingues, Regina M C P; Lobo, Leandro A

    2016-06-01

    Bacteroides fragilis is the most commonly isolated anaerobic bacteria from infectious processes. Several virulence traits contribute to the pathogenic nature of this bacterium, including the ability to tolerate the high concentrations of bile found in the gastrointestinal tract (GIT). The activity of bile salts is similar to detergents and may lead to membrane permeabilization and cell death. Modulation of outer membrane proteins (OMPs) is considered a crucial event to bile salts resistance. The primary objective of the current work was to identify B. fragilis proteins associated with the stress induced by high concentration of bile salts. The outer membrane of B. fragilis strain 638R was isolated after growth either in the presence of 2% conjugated bile salts or without bile salts. The membrane fractions were separated on SDS-PAGE and analyzed by ESI-Q/TOF tandem mass spectrometry. A total of 37 proteins were identified; among them nine were found to be expressed exclusively in the absence of bile salts whereas eight proteins were expressed only in the presence of bile salts. These proteins are related to cellular functions such as transport through membrane, nutrient uptake, and protein-protein interactions. This study demonstrates the alteration of OMPs composition in B. fragilis during bile salts stress resistance and adaptation to environmental changes. Proteomics of OMPs was also shown to be a useful approach in the identification of new targets for functional analyses.

  2. Identification of antimicrobial resistance genes in multidrug-resistant clinical Bacteroides fragilis isolates by whole genome shotgun sequencing

    DEFF Research Database (Denmark)

    Sydenham, Thomas Vognbjerg; Sóki, József; Hasman, Henrik;

    2015-01-01

    Bacteroides fragilis constitutes the most frequent anaerobic bacterium causing bacteremia in humans. The genetic background for antimicrobial resistance in B. fragilis is diverse with some genes requiring insertion sequence (IS) elements inserted upstream for increased expression. To evaluate whole...... genetic data will most likely require complete or nearly complete genomes. Current approaches to this are laborious and/or costly. Emerging technologies such as nanopore based single DNA strand sensing could perhaps provide a solution in the future....

  3. Different metabolic features of Bacteroides fragilis growing in the presence of glucose and exopolysaccharides of bifidobacteria

    Directory of Open Access Journals (Sweden)

    David eRios-Covian

    2015-08-01

    Full Text Available Bacteroides is among the most abundant microorganism inhabiting the human intestine. They are saccharolytic bacteria able to use dietary or host-derived glycans as energy sources. Some Bacteroides fragilis strains contribute to the maturation of the immune system but it is also an opportunistic pathogen. The intestine is the habitat of most Bifidobacterium species, some of whose strains are considered probiotics. Bifidobacteria can synthesize exopolysaccharides (EPS, which are complex carbohydrates that may be available in the intestinal environment. We studied the metabolism of B. fragilis when an EPS preparation from bifidobacteria was added to the growth medium compared to its behavior with added glucose. 2D-DIGE coupled with the identification by MALDI-TOF/TOF evidenced proteins that were differentially produced when EPS was added. The results were supported by RT-qPCR gene expression analysis. The intracellular and extracellular pattern of certain amino acids, the redox balance and the α-glucosidase activity were differently affected in EPS with respect to glucose. These results allowed us to hypothesize that three general main events, namely the activation of amino acids catabolism, enhancement of the transketolase reaction from the pentose-phosphate cycle, and activation of the succinate-propionate pathway, promote a shift of bacterial metabolism rendering more reducing power and optimizing the

  4. Suppression of colorectal tumorigenesis by recombinant Bacteroides fragilis enterotoxin-2 in vivo

    Science.gov (United States)

    Lv, You; Ye, Tao; Wang, Hui-Peng; Zhao, Jia-Ying; Chen, Wen-Jie; Wang, Xin; Shen, Chen-Xia; Wu, Yi-Bin; Cai, Yuan-Kun

    2017-01-01

    AIM To evaluate the impact of recombinant Bacteroides fragilis enterotoxin-2 (BFT-2, or Fragilysin) on colorectal tumorigenesis in mice induced by azoxymethane/dextran sulfate sodium (AOM/DSS). METHODS Recombinant proBFT-2 was expressed in Escherichia coli strain Rosetta (DE3) and BFT-2 was obtained and tested for its biological activity via colorectal adenocarcinoma cell strains SW-480. Seventy C57BL/6J mice were randomly divided into a blank (BC; n = 10), model (AD; n = 20), model + low-dose toxin (ADLT; n = 20, 10 μg), and a model + high-dose toxin (ADHT; n = 20, 20 μg) group. Mice weight, tumor formation and pathology were analyzed. Immunohistochemistry determined Ki-67 and Caspase-3 expression in normal and tumor tissues of colorectal mucosa. RESULTS Recombinant BFT-2 was successfully obtained, along with its biological activity. The most obvious weight loss occurred in the AD group compared with the ADLT group (21.82 ± 0.68 vs 23.23 ± 0.91, P < 0.05) and the ADHT group (21.82 ± 0.68 vs 23.57 ± 1.06, P < 0.05). More tumors were found in the AD group than in the ADLT and ADHT groups (19.75 ± 3.30 vs 6.50 ± 1.73, P < 0.05; 19.75 ± 3.30 vs 6.00 ± 2.16, P < 0.05). Pathology showed that 12 mice had adenocarcinoma and 6 cases had adenoma in the AD group. Five mice had adenocarcinoma and 15 had adenoma in the ADLT group. Four mice had adenocarcinoma and 16 had adenoma in the ADHT group. The incidence of colorectal adenocarcinoma in both the ADHT group and the ADHT group was reduced compared to that in the AD group (P < 0.05, P < 0.05). The positive rate of Ki-67 in the ADLT group and the ADHT group was 50% and 40%, respectively, both of which were lower than that found in the AD group (94.44%, P < 0.05, P < 0.05). Caspase-3 expression in the ADLT group and the ADHT group was 45% and 55%, both of which were higher than that found in the BC group (16.67%, P < 0.05, P < 0.05). CONCLUSION Oral administration with lower-dose biologically active recombinant BFT-2

  5. Evaluation of Bacteroides fragilis GB-124 bacteriophages as novel human-associated faecal indicators in the United States

    Science.gov (United States)

    Phages infecting human-associated Bacteroides fragilis (GB-124 phages) have been employed in the European Union (EU) to identify human fecal pollution, but their utility for U.S. was unclear. Primary sewage effluent samples were collected seasonally from seven wastewater treatme...

  6. Structures of Bacteroides fragilis uridine 5'-diphosphate-N-acetylglucosamine (UDP-GlcNAc) acyltransferase (BfLpxA).

    Science.gov (United States)

    Ngo, Alice; Fong, Kai T; Cox, Daniel L; Chen, Xi; Fisher, Andrew J

    2015-05-01

    Uridine 5'-diphosphate-N-acetylglucosamine (UDP-GlcNAc) acyltransferase (LpxA) catalyzes a reversible reaction for adding an O-acyl group to the GlcNAc in UDP-GlcNAc in the first step of lipid A biosynthesis. Lipid A constitutes a major component of lipopolysaccharides, also referred to as endotoxins, which form the outer monolayer of the outer membrane of Gram-negative bacteria. Ligand-free and UDP-GlcNAc-bound crystal structures of LpxA from Bacteroides fragilis NCTC 9343, the most common pathogenic bacteria found in abdominal abscesses, have been determined and are presented here. The enzyme crystallizes in a cubic space group, with the crystallographic threefold axis generating the biological functional homotrimer and with each monomer forming a nine-rung left-handed β-helical (LβH) fold in the N-terminus followed by an α-helical motif in the C-terminus. The structure is highly similar to LpxA from other organisms. Yet, despite sharing a similar LβH structure with LpxAs from Escherichia coli and others, previously unseen calcium ions are observed on the threefold axis in B. fragilis LpxA to help stabilize the trimeric assembly.

  7. Polyamine catabolism contributes to enterotoxigenic Bacteroides fragilis-induced colon tumorigenesis.

    Science.gov (United States)

    Goodwin, Andrew C; Destefano Shields, Christina E; Wu, Shaoguang; Huso, David L; Wu, XinQun; Murray-Stewart, Tracy R; Hacker-Prietz, Amy; Rabizadeh, Shervin; Woster, Patrick M; Sears, Cynthia L; Casero, Robert A

    2011-09-13

    It is estimated that the etiology of 20-30% of epithelial cancers is directly associated with inflammation, although the direct molecular events linking inflammation and carcinogenesis are poorly defined. In the context of gastrointestinal disease, the bacterium enterotoxigenic Bacteroides fragilis (ETBF) is a significant source of chronic inflammation and has been implicated as a risk factor for colorectal cancer. Spermine oxidase (SMO) is a polyamine catabolic enzyme that is highly inducible by inflammatory stimuli resulting in increased reactive oxygen species (ROS) and DNA damage. We now demonstrate that purified B. fragilis toxin (BFT) up-regulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent generation of ROS and induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in C57BL/6 mice is associated with increased SMO expression and treatment of mice with an inhibitor of polyamine catabolism, N(1),N(4)-bis(2,3-butandienyl)-1,4-butanediamine (MDL 72527), significantly reduces ETBF-induced chronic inflammation and proliferation. Most importantly, in the multiple intestinal neoplasia (Min) mouse model, treatment with MDL 72527 reduces ETBF-induced colon tumorigenesis by 69% (P < 0.001). The results of these studies indicate that SMO is a source of bacteria-induced ROS directly associated with tumorigenesis and could serve as a unique target for chemoprevention.

  8. Polyamine catabolism contributes to enterotoxigenic Bacteroides fragilis-induced colon tumorigenesis

    Science.gov (United States)

    Goodwin, Andrew C.; Shields, Christina E. Destefano; Wu, Shaoguang; Huso, David L.; Wu, XinQun; Murray-Stewart, Tracy R.; Hacker-Prietz, Amy; Rabizadeh, Shervin; Woster, Patrick M.; Sears, Cynthia L.; Casero, Robert A.

    2011-01-01

    It is estimated that the etiology of 20–30% of epithelial cancers is directly associated with inflammation, although the direct molecular events linking inflammation and carcinogenesis are poorly defined. In the context of gastrointestinal disease, the bacterium enterotoxigenic Bacteroides fragilis (ETBF) is a significant source of chronic inflammation and has been implicated as a risk factor for colorectal cancer. Spermine oxidase (SMO) is a polyamine catabolic enzyme that is highly inducible by inflammatory stimuli resulting in increased reactive oxygen species (ROS) and DNA damage. We now demonstrate that purified B. fragilis toxin (BFT) up-regulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent generation of ROS and induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in C57BL/6 mice is associated with increased SMO expression and treatment of mice with an inhibitor of polyamine catabolism, N1,N4-bis(2,3-butandienyl)-1,4-butanediamine (MDL 72527), significantly reduces ETBF-induced chronic inflammation and proliferation. Most importantly, in the multiple intestinal neoplasia (Min) mouse model, treatment with MDL 72527 reduces ETBF-induced colon tumorigenesis by 69% (P < 0.001). The results of these studies indicate that SMO is a source of bacteria-induced ROS directly associated with tumorigenesis and could serve as a unique target for chemoprevention. PMID:21876161

  9. Oxygen-independent killing of Bacteroides fragilis by granule extracts from human polymorphonuclear leukocytes.

    Science.gov (United States)

    Wetherall, B L; Pruul, H; McDonald, P J

    1984-03-01

    Granule proteins from human neutrophils were prepared by extraction with acetate, and their antibacterial activity against Bacteroides fragilis was determined. Activity was highly dependent on pH; greatest killing occurred at the most acid pH tested (pH 5.0). Optimum activity was observed at physiological ionic strength and low bacterial numbers. Killing was inhibited by incubation temperatures of less than 37 degrees C. Eight times more extract was required to kill 50% of stationary-phase bacteria, compared with those growing in logarithmic phase. The antibacterial effect of granule extract was destroyed by boiling, but some activity was retained after heating to 56 degrees C and 80 degrees C. Granule extract activity was tested under conditions in which oxygen-dependent antibacterial systems were inhibited. The rate and extent of killing was not affected by anaerobiosis, sodium azide, or cysteine hydrochloride. These results suggest that the activity of granule extract is independent of oxidative antibacterial systems, and therefore, under conditions that occur in anaerobic infections, potent leukocyte granule-associated mechanisms exist for the destruction of B. fragilis.

  10. Characterization of the RokA and HexA broad-substrate-specificity hexokinases from Bacteroides fragilis and their role in hexose and N-acetylglucosamine utilization.

    Science.gov (United States)

    Brigham, Christopher J; Malamy, Michael H

    2005-02-01

    Bacteroides fragilis, a human gastrointestinal commensal and an opportunistic pathogen, utilizes simple and complex sugars and polysaccharides for growth in the large intestine and at sites of infection. Because B. fragilis lacks transport-linked sugar phosphorylation systems, cytoplasmic kinase(s) was expected to be required for the phosphorylation of hexoses and hexosamines. We have now identified two hexose kinases that are important for growth of B. fragilis on glucose, mannose, and other sugars. One kinase (RokA), a member of the ROK family of proteins, was found to be the sole kinase for activation of N-acetyl-D-glucosamine (NAG). The other kinase (HexA) is responsible for the majority of the glucose kinase activity in the cell, although a hexA deletion mutant strain was not defective for growth on any substrate tested. Deletion of both the rokA and hexA kinase genes resulted in inability of the cell to use glucose, mannose, NAG, and many other sugars. We purified RokA and determined its approximate molecular mass to be 36.5 kDa. The purified RokA protein was shown to phosphorylate several substrates, including glucose, NAG, and mannose, but not N-acetylmannosamine or N-acetylneuraminic acid. Phylogenetic analysis of RokA showed that it is most similar to kinases from the Cytophaga-Flavibacterium-Bacteroides group, while HexA was most similar to other bacterial hexokinases and eukaryotic hexokinases.

  11. Distinct interactions with cellular E-cadherin of the two virulent metalloproteinases encoded by a Bacteroides fragilis pathogenicity island.

    Science.gov (United States)

    Remacle, Albert G; Shiryaev, Sergey A; Strongin, Alex Y

    2014-01-01

    Bacteroides fragilis causes the majority of Gram-negative anaerobic infections in the humans. The presence of a short, 6-kb, pathogenicity island in the genome is linked to enterotoxigenic B. fragilis (ETBF). The role of the enterotoxin in B. fragilis virulence, however, remains to be determined, as the majority of clinical isolates lack ETBF genes and healthy individuals carry enterotoxin-positive B. fragilis. The island encodes secretory metalloproteinase II (MPII) and one of three homologous enterotoxigenic fragilysin isoenzymes (FRA; also termed B. fragilis toxin or BFT). The secretory metalloproteinases expressed from the genes on the B. fragilis pathogenicity island may have pathological importance within the gut, not linked to diarrhea. MPII and FRA are counter-transcribed in the bacterial genome, implying that regardless of their structural similarity and overlapping cleavage preferences these proteases perform distinct and highly specialized functions in the course of B. fragilis infection. The earlier data by us and others have demonstrated that FRA cleaves cellular E-cadherin, an important adherens junction protein, and weakens cell-to-cell contacts. Using E-cadherin-positive and E-cadherin-deficient cancer cells, and the immunostaining, direct cell binding and pull-down approaches, we, however, demonstrated that MPII via its catalytic domain efficiently binds, rather than cleaves, E-cadherin. According to our results, E-cadherin is an adherens junction cellular receptor, rather than a proteolytic target, of the B. fragilis secretory MPII enzyme. As a result of the combined FRA and MPII proteolysis, cell-to-cell contacts and adherens junctions are likely to weaken further.

  12. An orthologue of Bacteroides fragilis NanH is the principal sialidase in Tannerella forsythia.

    Science.gov (United States)

    Thompson, Hayley; Homer, Karen A; Rao, Susmitha; Booth, Veronica; Hosie, Arthur H F

    2009-06-01

    Sialidase activity is a putative virulence factor of the anaerobic periodontal pathogen Tannerella forsythia, but it is uncertain which genes encode this activity. Characterization of a putative sialidase, SiaHI, by others, indicated that this protein alone may not be responsible for all of the sialidase activity. We describe a second sialidase in T. forsythia (TF0035), an orthologue of Bacteroides fragilis NanH, and its expression in Escherichia coli. Sialidase activity of the expressed NanH was confirmed by using 2'-(4-methylumbelliferyl)-alpha-D-N-acetylneuraminic acid as a substrate. Biochemical characterization of the recombinant T. forsythia NanH indicated that it was active over a broad pH range, with optimum activity at pH 5.5. This enzyme has high affinity for 2'-(4-methylumbelliferyl)-alpha-D-N-acetylneuraminic acid (K(m) of 32.9 +/- 10.3 microM) and rapidly releases 4-methylumbelliferone (V(max) of 170.8 +/- 11.8 nmol of 4-methylumbelliferone min(-1) mg of protein(-1)). E. coli lysates containing recombinant T. forsythia NanH cleave sialic acid from a range of substrates, with a preference for alpha2-3 glycosidic linkages. The genes adjacent to nanH encode proteins apparently involved in the metabolism of sialic acid, indicating that the NanH sialidase is likely to be involved in nutrient acquisition.

  13. Bacteroides fragilis lipopolysaccharide and inflammatory signaling in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Walter J. Lukiw

    2016-09-01

    Full Text Available The human microbiome consists of ~3.8x1013 symbiotic microorganisms that form a highly complex and dynamic ecosystem: the gastrointestinal (GI tract constitutes the largest repository of the human microbiome by far, and its impact on human neurological health and disease is becoming increasingly appreciated. Bacteroidetes, the largest phylum of gram-negative bacteria in the GI tract microbiome, while generally beneficial to the host when confined to the GI tract, have potential to secrete a remarkably complex array of pro-inflammatory neurotoxins that include surface lipopolysaccharides (LPSs and toxic proteolytic species. The deleterious effects of these bacterial exudates appear to become more important as GI tract and blood-brain barriers alter or increase their permeability with aging and disease. For example, presence of the unique LPSs of the abundant Bacteroidetes species Bacteroides fragilis (BF-LPS in the serum represents a major contributing factor to systemic inflammation. BF-LPS is further recognized by TLR2, TLR4 and/or CD14 microglial cell receptors as are the pro-inflammatory 42 amino acid amyloid-beta (Aβ42 peptides that characterize Alzheimer’s disease (AD brain. Here we provide the first evidence that BF-LPS exposure to human primary brain cells is an exceptionally potent inducer of the pro-inflammatory transcription factor NF-kB (p50/p65 complex, a known trigger in the expression of pathogenic pathways involved in inflammatory neurodegeneration. This ‘Perspectives communication’ will in addition highlight work from recent studies that advance novel and emerging concepts on the potential contribution of microbiome-generated factors, such as BF-LPS, in driving pro-inflammatory degenerative neuropathology in the AD brain.

  14. Effect of the oral intake of yogurt containing Bifidobacterium longum BB536 on the cell numbers of enterotoxigenic Bacteroides fragilis in microbiota.

    Science.gov (United States)

    Odamaki, Toshitaka; Sugahara, Hirosuke; Yonezawa, Sumiko; Yaeshima, Tomoko; Iwatsuki, Keiji; Tanabe, Soichi; Tominaga, Tomoya; Togashi, Hideo; Benno, Yoshimi; Xiao, Jin-zhong

    2012-02-01

    Enterotoxigenic Bacteroides fragilis (ETBF) strains have been suggested to be associated with acute and persistent diarrheal disease, inflammatory bowel disease and colorectal cancer, although further epidemiological studies are needed for clarification. Here, a pilot study was performed to examine the effect of the oral administration of yogurt supplemented with a probiotic strain on the cell numbers of fecal ETBF in a healthy population. Among 420 healthy adults, 38 subjects were found to be ETBF carriers, giving a prevalence of approximately 9%. Among them, 32 subjects were enrolled in an open, randomized, parallel-group study to ingest yogurt supplemented with a probiotic strain, Bifidobacterium longum BB536 (BB536Y group), for 8 weeks, with milk provided to the control group (milk group). The cell numbers of ETBF and the dominant species of the B. fragilis group were measured by a quantitative PCR method. Compared with the baseline values, there was a significant decrease in the cell number of ETBF at week 8 in the BB536Y group but not in the milk group. Linear mixed models analysis for longitudinal data revealed a significant difference in the changes of ETBF cell number between the two groups during the intervention phase. These results imply the potential of probiotic yogurt for eliminating ETBF in the microbiota, but its clinical significance needs to be evaluated in the future. This is the first report of a possible effect of probiotic intake on ETBF in the microbiota.

  15. Analysis of the outer membrane proteome and secretome of Bacteroides fragilis reveals a multiplicity of secretion mechanisms.

    Directory of Open Access Journals (Sweden)

    Marlena M Wilson

    Full Text Available Bacteroides fragilis is a widely distributed member of the human gut microbiome and an opportunistic pathogen. Cell surface molecules produced by this organism likely play important roles in colonization, communication with other microbes, and pathogenicity, but the protein composition of the outer membrane (OM and the mechanisms used to transport polypeptides into the extracellular space are poorly characterized. Here we used LC-MS/MS to analyze the OM proteome and secretome of B. fragilis NCTC 9343 grown under laboratory conditions. Of the 229 OM proteins that we identified, 108 are predicted to be lipoproteins, and 61 are predicted to be TonB-dependent transporters. Based on their proximity to genes encoding TonB-dependent transporters, many of the lipoprotein genes likely encode proteins involved in nutrient or small molecule uptake. Interestingly, protease accessibility and biotinylation experiments indicated that an unusually large fraction of the lipoproteins are cell-surface exposed. We also identified three proteins that are members of a novel family of autotransporters, multiple potential type I protein secretion systems, and proteins that appear to be components of a type VI secretion apparatus. The secretome consisted of lipoproteins and other proteins that might be substrates of the putative type I or type VI secretion systems. Our proteomic studies show that B. fragilis differs considerably from well-studied Gram-negative bacteria such as Escherichia coli in both the spectrum of OM proteins that it produces and the range of secretion strategies that it utilizes.

  16. Monoclonal antibodies specific for Bacteroides fragilis enterotoxins BFT1 and BFT2 and their use in immunoassays

    Science.gov (United States)

    Kaplan, Paul M.

    2017-01-01

    We have developed 22 mouse IgG1 monoclonal antibodies (mAbs) against Bacteroides fragilis zinc metalloprotease toxins 1 and 2 (BFT1 and BFT2). Mice were immunized with recombinant BFT1 or BFT2 proteins with metalloprotease activity. Eight of the mAbs bind specifically to BFT1. One mAb, 2H6, binds specifically to BFT2. The remaining 13 mAbs bind to both BFT1 and BFT2. The eight BFT1-specific mAbs recognize at least five different epitopes on the toxin. Four of the BFT1-specific mAbs neutralized rBFT1 metalloprotease activity. Only one of these four mAbs, 1D9, neutralizes the cytotoxic effect of BFT1. Here, we describe the development of enzyme-linked immunosorbent assays (ELISAs) to detect BFT1 or BFT2 toxin in an isotype-specific manner. The sandwich ELISAs have a detection limit of 20 to 40 ng/ml when purified recombinant BFT protein is diluted into PBS. The sandwich ELISA can be used to distinguish and quantify levels of rBFT1 and rBFT2 in stool. This ELISA can be an important tool to investigate the association between BFT expression by enterotoxigenic B. fragilis and diseases such as diarrhea, inflammatory bowel disease and colorectal cancer. PMID:28257448

  17. Bacteroides Fragilis OmpA: Utility as a Live Vaccine Vector for Biodefense Agents

    Science.gov (United States)

    2008-01-01

    described extensively [25]. We have recently described these loops in monomeric porins from Acinetobacter baumannii [26], B. fragilis [14], and P...heat-modifiable proteins from the outer membrane of Porphyromonas asaccharolytica and Acinetobacter baumannii . Anaerobe 5, 43-50. 2 Jousimies-Somer...encoding a pore- forming protein from a clinical isolate of Acinetobacter baumannii . Curr. Microbiol. 47, 434-443. Table 1. Primers used for the

  18. Bacteroides Fragilis OmpA: Utility as a Live Vaccine Vector for Biodefense Agents

    Science.gov (United States)

    2009-01-01

    same results as the porin alone (data not shown). The supernatants containing the OmpA proteins were subjected to sodium dodecyl sulfate polyacrylamide ...thetaiotaomicron outer membrane protein that is essential for utilization of maltooligosaccharides and starch . J Bacteriol 178, 823-830. Reeves, A. R., Wang, G. R...Salyers, A. A. (1997).Characterization of four outer membrane proteins that play a role in utilization of starch by Bacteroides thetaiotaomicron

  19. Levofloxacin plus metronidazole administered once daily versus moxifloxacin monotherapy against a mixed infection of Escherichia coli and Bacteroides fragilis in an in vitro pharmacodynamic model.

    Science.gov (United States)

    Hermsen, Elizabeth D; Hovde, Laurie B; Sprandel, Kelly A; Rodvold, Keith A; Rotschafer, John C

    2005-02-01

    Moxifloxacin has been suggested as an option for monotherapy of intra-abdominal infections. Recent data support the use of a once-daily metronidazole regimen. The purpose of this study was to investigate the activity of levofloxacin (750 mg every 24 h [q24h]) plus metronidazole (1,500 mg q24h) compared with that of moxifloxacin (400 mg q24h) monotherapy in a mixed-infection model. By using an in vitro pharmacodynamic model in duplicate, Escherichia coli and Bacteroides fragilis were exposed to peak concentrations of 8.5 mg of levofloxacin/liter q24h, 32 mg of metronidazole/liter q24h, and 2 mg for moxifloxacin/liter q24h for 24 h. The activities of levofloxacin, metronidazole, moxifloxacin, and levofloxacin plus metronidazole were evaluated against E. coli, B. fragilis, and E. coli plus B. fragilis. The targeted half-lives of levofloxacin, metronidazole, and moxifloxacin were 8, 8, and 12 h, respectively. Time-kill curves were analyzed for time to 3-log killing, slope, and regrowth. Pre- and postexposure MICs were determined. The preexposure levofloxacin, metronidazole, and moxifloxacin MICs for E. coli and B. fragilis were 0.5 and 1, >64 and 0.5, and 1 and 0.25 mg/liter, respectively. Levofloxacin and moxifloxacin achieved a 3-log killing against E. coli and B. fragilis in all experiments, as did metronidazole against B. fragilis. Metronidazole did not decrease the starting inoculum of E. coli. The area under the concentration-time curve/MIC ratios for E. coli and B. fragilis were 171.7 and 85.9, respectively, for levofloxacin and 26 and 103.9, respectively, for moxifloxacin. Levofloxacin plus metronidazole exhibited the fastest rates of killing. The levofloxacin and moxifloxacin MICs for B. fragilis increased 8- to 16-fold after the organism was exposed to moxifloxacin. No other changes in the postexposure MICs were found. Levofloxacin plus metronidazole administered once daily exhibited activity similar to that of moxifloxacin against the mixed E. coli and B

  20. Determination of thermodynamic parameters of benzylpenicillin hydrolysis by metallo-β-lactamase CcrA from Bacteroides fragilis

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Le; Zhou, Li-Sheng; Liu, Cheng-Cheng; Shi, Ying; Zhou, Ya-Jun [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Yang, Ke-Wu, E-mail: kwyang@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China)

    2013-03-20

    Highlights: ► First report the thermokinetic parameters of benzylpenicillin hydrolysis with CcrA. ► The hydrolysis is a spontaneous and exothermic reaction with order of 1.4. ► Summarized that CcrA prefer to hydrolyze penicillins among β-lactam antibiotics. - Abstract: One of the most common way that bacteria become resistant to antibiotics is by the production of metallo-β-lactamases (MβLs) to hydrolyze the β-lactam-containing antibiotics. In this paper, the thermodynamic parameters of benzylpenicillin hydrolysis with B1 subclasses MβL CcrA (carbapenem and cephamycin resistance) from Bacteroides fragilis were determined by microcalorimetry. The activation free energy ΔG{sub ≠}{sup θ} is 87.90 ± 0.03, 88.99 ± 0.01, 89.93 ± 0.04 and 90.93 ± 0.05 kJ mol{sup −1} at 293.15, 298.15, 303.15 and 308.15 K, activation enthalpy ΔH{sub ≠}{sup θ} is 29.21 ± 0.03 kJ mol{sup −1}, activation entropy ΔS{sub ≠}{sup θ} is −200.34 ± 0.08 J mol{sup −1} K{sup −1}, the reaction order is 1.4, and the apparent activation energy E is 31.71 kJ mol{sup −1}. The thermodynamic characterization indicated that CcrA prefer to hydrolyze penicillins among three kinds of β-lactam-containing antibiotics.

  1. The symbiotic bacterial surface factor polysaccharide A on Bacteroides fragilis inhibits IL-1β-induced inflammation in human fetal enterocytes via toll receptors 2 and 4

    Science.gov (United States)

    Jiang, Fei; Meng, Di; Weng, Meiqian; Zhu, Weishu; Wu, Wenxue; Kasper, Dennis; Walker, W. Allan

    2017-01-01

    Colonizing bacteria interacting with the immature, unlike the mature, human intestine favors inflammation over immune homeostasis. As a result, ten percent of premature infants under 1500 grams weight develop an inflammatory necrosis of the intestine after birth, e.g., necrotizing enterocolitis (NEC). NEC is a major health problem in this population causing extensive morbidity and mortality and an enormous expenditure of health care dollars. NEC can be prevented by giving preterm infants their mother’s expressed breast milk or ingesting selective probiotic organisms. Vaginally delivered, breast fed newborns develop health promoting bacteria (“pioneer” bacteria) which preferentially stimulate intestinal host defense and anti-inflammation. One such “pioneer” organism is Bacteroides fragilis with a polysaccharide (PSA) on its capsule. B. fragilis has been shown developmentally in intestinal lymphocytes and dendritic cells to produce a balanced T-helper cell (TH1/TH2) response and to reduce intestinal inflammation by activity through the TLR2 receptor stimulating IL-10 which inhibits IL-17 causing inflammation. No studies have been done on the role of B. fragilis PSA on fetal enterocytes and its increased inflammation. Accordingly, using human and mouse fetal intestinal models, we have shown that B. fragilis with PSA and PSA alone inhibits IL-1β-induced IL-8 inflammation in fetal and NEC intestine. We have also begun to define the mechanism for this unique inflammation noted in fetal intestine. We have shown that B. fragilis PSA anti-inflammation requires both the TLR2 and TLR4 receptor and is in part mediated by the AP1 transcription factor (TLR2) which is developmentally regulated. These observations may help to devise future preventative treatments of premature infants against NEC. PMID:28278201

  2. In vitro activity of trovafloxacin against Bacteroides fragilis in mixed culture with either Escherichia coli or a vancomycin- resistant strain of Enterococcus faecium determined by an anaerobic time-kill technique.

    NARCIS (Netherlands)

    L.E.T. Stearne (Lorna); C. Kooi; W.H.F. Goessens (Wil); I.A.J.M. Bakker-Woudenberg (Irma); I.C. Gyssens (Inge)

    2001-01-01

    textabstractTo determine the efficacy of trovafloxacin as a possible treatment for intra-abdominal abscesses, we have developed an anaerobic time-kill technique using different inocula to study the in vitro killing of Bacteroides fragilis in pure culture or in mixed cul

  3. Demonstration of bacteroides capsules by light microscopy and ultrastructural cytochemistry.

    Science.gov (United States)

    Strohm, H; Payne, C M; Ryan, K J

    1983-05-01

    Forty-six anaerobic gram-negative bacilli, including 26 members of the Bacteroides fragilis group (BFG), were examined for capsules by the India ink technic. Thirty-five were encapsulated, including all the BFG strains. As a follow-up, seven of these isolates and two previously studied reference strains (B. fragilis ATCC 23745 and Bacteroides vulgatus ATCC 8482) were examined for capsules by ultrastructural cytochemistry. Using the periodic acid thiocarbohydrazide silver proteinate (PATCSP) method of Thiéry, all the BFG examined were encapsulated. In addition to the reference strains, this included one strain of B. fragilis and four of Bacteroides thetaiotaomicron. One non-BFG strain showed no capsular material. Differences between these results and those reported previously with the ruthenium red technic may reflect species differences in the chemical composition of Bacteroides capsules.

  4. Phenotypic detection of the cfiA metallo-β-lactamase in Bacteroides fragilis with the meropenem-EDTA double-ended Etest and the ROSCO KPC/MBL Confirm Kit

    DEFF Research Database (Denmark)

    Schwensen, Simon A; Acar, Ziyap; Sydenham, Thomas V

    2016-01-01

    OBJECTIVES: To investigate the performance of the meropenem and imipenem double-ended Etest ± EDTA and the tablet-based (meropenem and meropenem + dipicolinic acid) KPC/MBL Confirm Kit to detect cfiA metallo-β-lactamase (MBL) in Bacteroides fragilis. METHODS: Well-characterized B. fragilis isolates......-ended Etest gave an MIC ratio ≥8 (positive test) with all the isolates. All isolates that were meropenem intermediate or resistant had a zone diameter difference ≥6 mm with the KPC/MBL Confirm Kit. CONCLUSIONS: The meropenem double-ended Etest and not imipenem should be preferred for phenotypic detection...... of MBLs in B. fragilis. The KPC/MBL Confirm Kit could be an alternative with isolates that are meropenem intermediate or resistant (MIC >2 mg/L)....

  5. The Dysregulation of Polyamine Metabolism in Colorectal Cancer Is Associated with Overexpression of c-Myc and C/EBPβ rather than Enterotoxigenic Bacteroides fragilis Infection

    Directory of Open Access Journals (Sweden)

    Anastasiya V. Snezhkina

    2016-01-01

    Full Text Available Colorectal cancer is one of the most common cancers in the world. It is well known that the chronic inflammation can promote the progression of colorectal cancer (CRC. Recently, a number of studies revealed a potential association between colorectal inflammation, cancer progression, and infection caused by enterotoxigenic Bacteroides fragilis (ETBF. Bacterial enterotoxin activates spermine oxidase (SMO, which produces spermidine and H2O2 as byproducts of polyamine catabolism, which, in turn, enhances inflammation and tissue injury. Using qPCR analysis, we estimated the expression of SMOX gene and ETBF colonization in CRC patients. We found no statistically significant associations between them. Then we selected genes involved in polyamine metabolism, metabolic reprogramming, and inflammation regulation and estimated their expression in CRC. We observed overexpression of SMOX, ODC1, SRM, SMS, MTAP, c-Myc, C/EBPβ (CREBP, and other genes. We found that two mediators of metabolic reprogramming, inflammation, and cell proliferation c-Myc and C/EBPβ may serve as regulators of polyamine metabolism genes (SMOX, AZIN1, MTAP, SRM, ODC1, AMD1, and AGMAT as they are overexpressed in tumors, have binding site according to ENCODE ChIP-Seq data, and demonstrate strong coexpression with their targets. Thus, increased polyamine metabolism in CRC could be driven by c-Myc and C/EBPβ rather than ETBF infection.

  6. In Vivo Efficacy of Trovafloxacin against Bacteroides fragilis in Mixed Infection with either Escherichia coli or a Vancomycin-Resistant Strain of Enterococcus faecium in an Established-Abscess Murine Model

    OpenAIRE

    2001-01-01

    The pharmacodynamic and pharmacokinetic properties of trovafloxacin were studied in a standardized murine model of established subcutaneous abscesses. Daily dosing regimens of 37.5 to 300 mg/kg every 8 h (q8h) or every 24 h (q24h) were started 3 days after inoculation with mixtures containing either Bacteroides fragilis-Escherichia coli-autoclaved cecal contents (ACC) or B. fragilis–vancomycin-resistant Enterococcus faecium (VREF)–ACC. Treatment was continued for 3 or 5 days. The efficacy of ...

  7. In vivo efficacy of trovafloxacin against Bacteroides fragilis in mixed infection with either Escherichia coli or a vancomycin-resistant strain of Enterococcus faecium in an established-abscess murine model.

    Science.gov (United States)

    Stearne, L E; Gyssens, I C; Goessens, W H; Mouton, J W; Oyen, W J; van der Meer, J W; Verbrugh, H A

    2001-05-01

    The pharmacodynamic and pharmacokinetic properties of trovafloxacin were studied in a standardized murine model of established subcutaneous abscesses. Daily dosing regimens of 37.5 to 300 mg/kg every 8 h (q8h) or every 24 h (q24h) were started 3 days after inoculation with mixtures containing either Bacteroides fragilis-Escherichia coli-autoclaved cecal contents (ACC) or B. fragilis-vancomycin-resistant Enterococcus faecium (VREF)-ACC. Treatment was continued for 3 or 5 days. The efficacy of treatment was determined by the decrease in abscess bacterial counts and abscess weights, as well as by the reduction in inflammation (biodistribution of (99m)Tc-HYNIC immunoglobulin G) compared to saline-treated controls. Trovafloxacin showed a significant dose-response effect on the bacterial counts, weight, and inflammation of B. fragilis-E. coli abscesses after 3 and/or 5 days of treatment. A maximum 3.4 and 3.1 log(10) reduction in CFU/abscess in the respective B. fragilis and E. coli bacterial counts was attained after 5 days of treatment with daily doses of 300 mg/kg. The peak serum concentration was more predictive for effect than the area under the concentration-time curve. The C(max) was the pharmacodynamic index most predictive for success, and the efficacy of the q24h regimens was significantly better than the q8h regimens. The antibiotic was ineffective against the VREF in mixed infection with B. fragilis, while the killing of the anaerobe in the same combination was significantly less than in the E. coli combination (P abscesses. In addition, we have shown for the first time that a decrease in bacterial numbers also leads to a reduction in both abscess weight and inflammation.

  8. Preparation and Identification of Polyclonal Antibody Against a Nov-el α-Galactosidase from Bacteroides fragilis%新型α-半乳糖苷酶多克隆抗体的制备及特异性鉴定

    Institute of Scientific and Technical Information of China (English)

    李素波; 高红伟; 张雪; 鲍国强; 檀英霞; 王颖丽; 季守平; 宫锋

    2013-01-01

    目的:制备高效价、高特异性的新型α-半乳糖苷酶的兔多抗,并鉴定该抗体的特异性。方法:用脆弱类杆菌来源的基因重组α-半乳糖苷酶(纯度大于90%)免疫新西兰大白兔,获得α-半乳糖苷酶的兔抗血清,并经HiTrap rProtein A柱纯化获得高纯度的抗体;用间接ELISA法检测抗体效价,Western印迹评价抗体的特异性。结果:通过免疫法得到了α-半乳糖苷酶的兔多克隆抗体血清,抗体效价达1∶1×106,经rProtein A柱纯化后获得了高效价、高纯度的抗体,Western印迹显示该抗体特异性地与新型α-半乳糖苷酶结合。结论:获得了新型α-半乳糖苷酶的高效价、高特异性的兔多克隆抗体,可用于血型转变过程中残留α-半乳糖苷酶含量的特异性检测。%Objective: To prepare high titer and high specific rabbit polyclonal antibody against a novel α-galac-tosidase from Bacteroides fragilis. Methods: The New Zealand rabbits were immunized with purified recombinant bacteria α-galactosidase(the purity>90%). Rabbit sera were purified by HiTrap rProtein A column, and its titer and specificity were detected by ELISA and Western blotting respectively Results: The purity of antibody protein was about 95%. And the titer of rabbit sera were 1∶1 × 106. Western blotting showed that the antibody reacted with α-galactosidase only. Conclusion: We had obtained high titer and high purity rabbit polyclonal antibody ofα-galactosidase. The antibody can be used in detecting the minimal amount of residual α-galactosidase involved in conversion of blood type B to O.

  9. Epidemiology and antimicrobial resistance of B. fragilis group organisms isolated from clinical specimen and human intestinal microbiota Epidemiologia e resistência a antimicrobianos de microorganismos do grupo B. fragilis isolados de espécime clínico e microbiota intestinal humana

    Directory of Open Access Journals (Sweden)

    Cibele Barreto Mano de Carvalho

    1996-10-01

    Full Text Available Epidemiological aspects and the antimicrobial susceptibility profile of the Bacteroides fragilis group isolated from clinical and human intestinal specimens were examined in this study. B. fragilis group strains were isolated from 46 (37% of 124 clinical specimens and the source of the samples was: Blood culture (3, intraabdominal infection (27, brain abscess (2, soft tissue infection (17, respiratory sinus (3, pleural aspirate (9, breast abscess (3, surgical infected wound (22, pelvic inflammatory disease (22, chronic otitis media (9 and miscellaneous (7. Intraabdominal and soft tissue infections were responsible for more than half of the clinical isolates. Susceptibility to penicillin, cefoxitin, tetracycline, metronidazole, chloramphenicol and clindamycin was examined. All isolates were susceptible to metronidazole and chloramphenicol. For clindamycin and cefoxitin the resistance rates observed were 21.7% and 10.9% respectively. Susceptibility profiles varied among the different species tested. A total of 37 species of B. fragilis group isolated from intestinal microbiota of individuals who had no antimicrobial therapy for at least 1 month before the sampling was also examined. All strains were also susceptible to chloramphenicol and motronidazole and the resistance rates to clindamycin and cefoxitin were 19.4% and 5.4% respectively. A few institutions, in Brazil, have monitored the antimicrobial susceptibility of B. fragilis group strains isolated from anaerobic infections. The resistance rates to cefoxitin and clindamycin and the variation in susceptibility patterns among the species isolated in this study emphasize the need for monitoring of susceptibility patterns of B. fragilis group organisms isolated, especially at our University Hospitals.Alguns aspectos epidemiológicos e o perfil de sensibilidade a antimicrobianos de amostras do grupo B. fragilis isoladas de espécime clínico e microbiota intestinal humana foram delineados neste

  10. Development of EUCAST disk diffusion method for susceptibility testing of the Bacteroides fragilis group isolates

    DEFF Research Database (Denmark)

    Nagy, Elisabeth; Justesen, Ulrik Stenz; Eitel, Zsuzsa

    2015-01-01

    -clavulanic acid, cefoxitin, clindamycin, imipenem, metronidazole, moxifloxacin, piperacillin/tazobactam, tigecycline by agar dilution method previously. The inhibition zones of the same antibiotics including meropenem disc were determined by the disc diffusion on Brucella blood agar supplemented with haemin...

  11. In Vitro Kinetic Analysis of Oligofructose Consumption by Bacteroides and Bifidobacterium spp. Indicates Different Degradation Mechanisms

    OpenAIRE

    Van der Meulen, Roel; Makras, Lefteris; Verbrugghe, Kristof; Adriany, Tom; De Vuyst, Luc

    2006-01-01

    The growth of pure cultures of Bacteroides thetaiotaomicron LMG 11262 and Bacteroides fragilis LMG 10263 on fructose and oligofructose was examined and compared to that of Bifidobacterium longum BB536 through in vitro laboratory fermentations. Gas chromatography (GC) analysis was used to determine the different fractions of oligofructose and their degradation during the fermentation process. Both B. thetaiotaomicron LMG 11262 and B. fragilis LMG 10263 were able to grow on oligofructose as fas...

  12. Bacteroides species from the oral cavity and oral-associated diseases of cats.

    Science.gov (United States)

    Love, D N; Johnson, J L; Moore, L V

    1989-03-01

    One hundred and sixty-seven strains of Bacteroides were isolated from 71 subcutaneous fight-wound abscesses of cats, 21 cases of feline pyothorax, normal gingival margins from 10 cats and 6 cases of feline gingivitis. Bacteroides species constituted (as a proportion of all anaerobic isolates examined) 44.5% from subcutaneous abscesses, 33.7% from pyothoraxes, 37.5% from normal gingiva and 27.7% from diseased gingiva. Bacteroides tectum comprised 43.7% or 73 of 167 strains, followed by the black- or brown-pigmented asaccharolytic feline species of B. gingivalis, B. salivosus and Group B, comprising 32.3% or 54 of 167 strains. B. heparinolyticus (some 10% or 17 of 167 strains) was the next most common species described. The remainder consisted of two strains of B. fragilis and 21 unspeciated strains. Bacteroides tectum was frequently isolated from subcutaneous abscesses (43.7%) and pyothoraxes (46.6%), and it constituted some 33% of anaerobic isolated from normal gingiva. Bacteroides heparinolyticus was more commonly encountered in purulent lesions (abscesses and pyothoraxes) than in the oral cavity.

  13. 抗脆弱类杆菌和产气荚膜杆菌McAb池在外科感染快速诊断中的应用%Application of monoclonal antibody pool against Bacteroides fragilis and Clostridium perfringens in rapid diagnosis in surgical infection

    Institute of Scientific and Technical Information of China (English)

    张雅萍; 甘露; 常山

    2001-01-01

    目的 制备抗脆弱类杆菌和抗产气荚膜杆菌单克隆抗体池,并用于快速诊断及时指导临床治疗。方法 采用间接免疫荧光抗体染色法(IFA)和免疫酶标抗体染色法(ELA)对我院1998~1999年191例外科感染患者的标本进行细菌学检测,并与常规培养法进行比较。结果 3种方法从191份标本中分别检出脆弱类杆菌53株(27.7%)和55株(28.8%)以及25株(13.1%);检出产气荚膜杆菌12株(6.3%)和11株(5.8%)以及6株(3.1%)。IFA和ELA法2种厌氧菌检出率明显高于CM法。但IFA和ELA法之间检出率差异无显著性。结论 自制抗脆弱类杆菌和抗产气荚膜杆菌的McAb池,检测平时常见的脆弱类杆菌和战时常见的产气荚膜杆菌,敏感性高,特异性强,简便,快速,便于推广。%Objective To prepare monoclonal antibody (McAb) pool against Bacteroides fragilis and Clostridium perfringens and evaluated its effect in rapid diagnosis in surgical infection. Methods After the preparation of monoclonal antibodies against B. fragilis and C. perfringens, 191 specimens collected from infectious patients was detected with indirect immunofluorescent antibody (IFA) and enzyme labeled antibody (ELA). The results were compared with routine cultural method (CM). Results Among the 191 specimens, 53 (27.7%), 55 (28.8%) and 25 (13.1%)strains of B. fragilis were detected with IFA, ELA and CM respectively, and for C.perfringens, 12(6.3%), 11(5.8%), and 6(3.1%) strains were found. The detectable rate of anaerobic bacteria by IFA and ELA was higher than by CM, but no difference was found between these 2. Conclusion The self-made McAb pool against B.fagilis and C.perfringens might be a rapid, specific, sensitive and simple McAb pool for detecting B.fragilis in surgical infection and C.perfringens in wartime.

  14. Talking of... Dientamoeba fragilis

    OpenAIRE

    Giulia Zorzi; Ettore De Canale; Lucia Rossi; Valeria Besutti

    2013-01-01

    Introduction: Dientamoeba fragilis is a protozoan parasite of human gastrointestinal tract with worldwide distribution and a controversial pathogenic role. Data on prevalence and geographical distribution are underestimated for difficult microscopic recognition and “fragility” of the protozoan. Generally to perform the O & P exam for identification of D. fragilis it is necessary to recur to a permanent stain and to an expert microscopist. Methods: we analyzed fecal samples of 3907 patient...

  15. Pigment production by Bacteroides species with reference to sub-classification.

    Science.gov (United States)

    Duerden, B I

    1975-02-01

    All six reference strains of Bacteroides species, 36 laboratory isolates conforming to this group, and individual strains of Escherichia coli, Proteus mirabilis, Salmonella typhimurium and Clostridum welchii produced a dense black pigment, identified as ferrus sulphide, when grown in cooked-meat media containing cystine and ferrous sulphate. This was an indicator effect resulting from the production of H2S by the bacteria in the presence of ferrous ions and was unrelated to the characteristic pigment produced by strains of B. melaninogenicus when grown on blood agar. A pigment was extracted by ultrasonic disintegration of washed cells of three reference strains of B. melanino-genicus grown for 1 week in horse-blood broth and on human-blood agar. It was intracellular or cell-associated, soluble in water and had the spectrophotometric characteristics of a derivative of haemoglobin. No such pigment was extracted from strains of B. fragilis or B. necrophorus by similar procedures. Pigment production is a stable characteristic of those strains of Bacteroides called B. melaninogenicus and it is a significant property in the classification of the Bacteroides group. However, the pigment-producing strains are not a homogenous species, and there were considerable differences between the results of biochemical tests and antibograms obtained with the three strains of B. melaninogenicus.

  16. Plasmidos R en especies de "bacteroides"

    OpenAIRE

    Jiménez Díaz, Rufino

    1982-01-01

    Se han aislado 60 estirpes de bacteroides del grupo fragilis de muestras clínicas procedentes del hospital Universitario de Sevilla que se clasificaron mediante pruebas bioquímicas y cromatografía liquido gas. Se ha estudiado su patr&oac ute;n de resistencia a antibióticos fundamentalmente del grupo b-lactámicos y su correlación con la producción de b-cactamasa. Se estudia la localización de los genes implicados en ambos caracteres; de los experimentos realizados puede deducirse que dichos g...

  17. Talking of... Dientamoeba fragilis

    Directory of Open Access Journals (Sweden)

    Giulia Zorzi

    2013-08-01

    Full Text Available Introduction: Dientamoeba fragilis is a protozoan parasite of human gastrointestinal tract with worldwide distribution and a controversial pathogenic role. Data on prevalence and geographical distribution are underestimated for difficult microscopic recognition and “fragility” of the protozoan. Generally to perform the O & P exam for identification of D. fragilis it is necessary to recur to a permanent stain and to an expert microscopist. Methods: we analyzed fecal samples of 3907 patients enrolled among the patients referred to the Service of Microbiology of Padova University Hospital for routine parassitology examinations from June 2011 to June 2012. The aim of this study was to document the prevalence and the clinical features of D. fragilis infection. The laboratory detection rate of the organism is greatly enhanced by use of preservative to fix stool specimens immediately after passage. As previously described for a rapid identification of D. fragilis, in unstained fixed fecal material by direct microscopy (400X, the demonstration of the characteristic “golf-club” and “acanthopodia-like” structures are suitable. Results: in this study the prevalence was found to be 6.8%, higher than our previous reports. Out of the 267 patients in which we detected D. fragilis, 26.0% presented with extra-intestinal symptoms, 19.8% reported gastrointestinal complaints and 17.0% referred abdominal pain. Conclusions: D. fragilis, even if considered a neglected parasite, is not rare and the presence of this fecal agent is associated to various intestinal and probably systemic clinical symptoms, even though asymptomatic carriers have been reported. D. fragilis infects in high rates among close household contacts; so the Authors stress the importance of screening close contacts to prevent re-infections after treatment.

  18. Dientamoeba fragilis, One of the Neglected Intestinal Protozoa.

    Science.gov (United States)

    Garcia, Lynne S

    2016-09-01

    Dientamoeba fragilis is a single-celled protozoan, closely related to the trichomonads. Reported worldwide as causing human gastrointestinal symptoms, D. fragilis is very common and is second only to Blastocystis spp. Dientamoebiasis equals or exceeds the incidence of giardiasis. This minireview includes diagnostic options, clinical relevance, therapy, an animal model, the confirmed cyst stage, and sequencing data. The development of a rodent model, fulfilling Koch's postulates, and the confirmation of a cyst stage have clarified transmission routes, including fecal-oral transmission. The prevalence of D. fragilis varies between 0% to over 82%; results depend on the geographic location, group studied, and diagnostic methods used.

  19. Analysis of Romanian Bacteroides isolates for antibiotic resistance levels and the corresponding antibiotic resistance genes.

    Science.gov (United States)

    Székely, Edit; Eitel, Zsuzsa; Molnár, Szabolcs; Szász, Izabella Éva; Bilca, Doina; Sóki, József

    2015-02-01

    As part of an ESCMID Study Group on Anaerobic Infections (ESGAI) project, a study was conducted to measure the antibiotic susceptibilities and corresponding gene contents of 53 Bacteroides fragilis group strains isolated in Romania. The antibiotic resistance data was comparable with the data found for other East-European countries. Here, no resistant isolate was found for imipenem, metronidazole and tigecycline. An increasing role of the cepA, cfxA and cfiA genes was observed in their corresponding antibiotic resistances. Moreover, no isolate was found that harbored the cfiA gene with a possible activating IS element. Clindamycin resistance was low, similarly to that the rate for the ermF gene. However, we did find some isolates with nimB, ermB, msrSA, linA, satG, tetX, tetM and bexA genes. This study was the first to provide antibiotic resistance data for clinical Bacteroides strains from Romania.

  20. Adhesion molecule expression stimulated by Bacteroides thetaiotaomicron cell-surface antigens.

    Science.gov (United States)

    Rokosz, A; Meisel-Mikołajczyk, F; Malchar, C; Nowaczyk, M; Górski, A

    1999-01-01

    Bacteroides thetaiotaomicron, a Gram-negative anaerobic rod belonging to the Bacteroides fragilis group (BFG), is involved in many systemic and local, most frequently suppurative infections in man. The cell envelope of these rods is composed of two carbohydrate-containing antigens: lipopolysaccharide (LPS) and capsular polysaccharide (CPS). Adhesion molecules ICAM-1, VCAM-1 and E-selectin (ELAM-1) are induced on the endothelial cells by mediators of inflammation. The aim of this study was to assay the ability of B. thetaiotaomicron surface antigens to induce adhesion molecule expression on the endothelial cells. The influence of LPS and CPS on the expression of adhesion molecules on HMEC-1 cell line was examined in an ELISA test. ELISA was performed with monoclonal mouse anti-human: ICAM-1, VCAM-1 and E-selectin antibodies of the IgG class. B. thetaiotaomicron lipopolysaccharides revealed the ability to induce ICAM-1, VCAM-1 and E-selectin expression on the endothelial cells. Their activities were similar, but lower than the activity of Eschericha coli LPS. ICAM-1 was the most stimulated adhesion molecule. The strongest activation by LPS was achieved at the concentrations of 10.0 and 1.0 micrograms/ml. The ability of capsular polysaccharide to induce the expression of adhesion molecules was considerably weaker.

  1. Metronidazole and spiramycin therapy of mixed Bacteroides spp. and Neisseria gonorrhoeae infection in mice.

    Science.gov (United States)

    Brook, I

    1989-01-01

    The in vitro and in vivo activity of metronidazole and spiramycin, used singly or in combination, was tested in the eradication of infection caused by Bacteroides spp. and Neisseria gonorrhoeae alone or in combination. The in vitro tests consisted of determinations of the minimal inhibitory concentrations (MIC), carried out with or without the addition of a constant amount of the other antimicrobials. The MIC of both Bacteroides bivius and Bacteroides fragilis for metronidazole were significantly reduced by the addition of spiramycin (from 0.5 to 0.125 micrograms/ml). The in vivo tests were carried out in mice and consisted of measurements of the effects of the antimicrobial agents on the bacterial contents of abscesses induced by subcutaneous injection of bacterial suspension. Synergism between metronidazole and spiramycin was noted against Bacteroides spp. in abscesses caused by either Bacteroides spp. alone, or in combination with N. gonorrhoeae. Furthermore, an additional reduction in the number of N gonorrhoeae was noted in mixed infection with Bacteroides that was treated with metronidazole alone. This study demonstrates the in vitro and in vivo efficacy of the combination of metronidazole and spiramycin in the treatment of infections caused by either Bacteroides spp. alone or in combination with N. gonorrhoeae.

  2. In vitro kinetic analysis of oligofructose consumption by Bacteroides and Bifidobacterium spp. indicates different degradation mechanisms.

    Science.gov (United States)

    Van der Meulen, Roel; Makras, Lefteris; Verbrugghe, Kristof; Adriany, Tom; De Vuyst, Luc

    2006-02-01

    The growth of pure cultures of Bacteroides thetaiotaomicron LMG 11262 and Bacteroides fragilis LMG 10263 on fructose and oligofructose was examined and compared to that of Bifidobacterium longum BB536 through in vitro laboratory fermentations. Gas chromatography (GC) analysis was used to determine the different fractions of oligofructose and their degradation during the fermentation process. Both B. thetaiotaomicron LMG 11262 and B. fragilis LMG 10263 were able to grow on oligofructose as fast as on fructose, succinic acid being the major metabolite produced by both strains. B. longum BB536 grew slower on oligofructose than on fructose. Acetic acid and lactic acid were the main metabolites produced when fructose was used as the sole energy source. Increased amounts of formic acid and ethanol were produced when oligofructose was used as an energy source at the cost of lactic acid. Detailed kinetic analysis revealed a preferential metabolism of the short oligofructose fractions (e.g., F2 and F3) for B. longum BB536. After depletion of the short fractions, the larger oligofructose fractions (e.g., F4, GF4, F5, GF5, and F6) were metabolized, too. Both Bacteroides strains did not display such a preferential metabolism and degraded all oligofructose fractions simultaneously, transiently increasing the fructose concentration in the medium. This suggests a different mechanism for oligofructose breakdown between the strain of Bifidobacterium and both strains of Bacteroides, which helps to explain the bifidogenic nature of inulin-type fructans.

  3. Molybdate transport by Bradyrhizobium japonicum bacteroids.

    OpenAIRE

    Maier, R J; Graham, L.

    1988-01-01

    Bacteroid suspensions of Bradyrhizobium japonicum USDA 136 isolated from soybeans grown in Mo-deficient conditions were able to transport molybdate at a nearly constant rate for up to 1 min. The apparent Km for molybdate was 0.1 microM, and the Vmax was about 5 pmol/min per mg (dry weight) of bacteroid. Supplementation of bacteroid suspensions with oxidizable carbon sources did not markedly increase molybdate uptake rates. Anaerobically isolated bacteroids accumulated twice as much Mo in 1 h ...

  4. Occurrence of bacteriophages infecting Bacteroides host strains (ARABA 84 and GB-124) in fecal samples of human and animal origin.

    Science.gov (United States)

    Diston, David; Wicki, Melanie

    2015-09-01

    Bacteriophage-based microbial source-tracking studies are an economical and simple way of identifying fecal sources in polluted water systems. Recently isolated Bacteroides spp. strains ARABA 84, and GB-124 have been shown to detect bacteriophages exclusively in aquatic systems impacted by human fecal material. To date, limited examination of the occurrence or concentration of phages capable of infecting Bacteroides fragilis strain GB-124 or B. thetaiotaomicron strain ARABA 84 in human and animal feces has been carried out. This study reports the prevalence rates and concentrations of phages infecting ARABA 84 and GB-124 host strains in human and a range of animal feces. Discrete human fecal samples (n=55) and pooled animal samples (n=46, representing the feces of over 230 animals) were examined for phages infecting the host strains ARABA 84, GB-124, and E. coli strain WG5. Both human Bacteroides host strains were highly specific (95% and 100% for ARABA 84 and GB-124, respectively), challenging results from previous studies. This study supports the use of Bacteroides strains GB-124 and ARABA 84 in fecal source tracking studies for the detection of human fecal contamination.

  5. Species differentiation of Bacteroides dorei from Bacteroides vulgatus and Bacteroides ovatus from Bacteroides xylanisolvens - Back to basics

    DEFF Research Database (Denmark)

    Micha Pedersen, Rune; Marmolin, Ea Sofie; Justesen, Ulrik S

    2013-01-01

    We present the results from 16S sequencing and phenotypic tests for differentiation of Bacteroides dorei from Bacteroides vulgatus and Bacteroides ovatus from Bacteroides xylanisolvens, which was not possible with MALDI-TOF MS. Testing with β-glucosidase could differentiate B. dorei from B. vulga....... vulgatus and a negative catalase reaction could identify B. xylanisolvens....

  6. Lower Level of Bacteroides in the Gut Microbiota Is Associated with Inflammatory Bowel Disease: A Meta-Analysis

    Science.gov (United States)

    Zhou, Yingting

    2016-01-01

    Background and Aims. Multiple studies have reported associations between inflammatory bowel disease (IBD) and the flora disequilibrium of Bacteroides. We performed a meta-analysis of the available data to provide a more precise estimate of the association between Bacteroides level in the gut and IBD. Methods. We searched PubMed/MEDLINE, EMBASE, Cochrane Library, Wiley Library, BIOSIS previews, Web of Science, CNKI, and ScienceDirect databases for published literature on IBD and gut microbiota from 1990 to 2016. Quality of all eligible studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS). We compared the level of Bacteroides in IBD patients with that in a control group without IBD, different types of IBD patients, and IBD patients with active phase and in remission. Results. We identified 63 articles, 9 of which contained sufficient data for evaluation. The mean level of Bacteroides was significantly lower in Crohn's disease (CD) and ulcerative colitis (UC) patients in active phase than in normal controls. The level of Bacteroides in remission CD and UC patients was much lower than patients in the control group. Bacteroides level was even lower in patients with CD and UC in active phase than in remission. Conclusions. This analysis suggests that lower levels of Bacteroides are associated with IBD, especially in active phase. PMID:27999802

  7. Lower Level of Bacteroides in the Gut Microbiota Is Associated with Inflammatory Bowel Disease: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Yingting Zhou

    2016-01-01

    Full Text Available Background and Aims. Multiple studies have reported associations between inflammatory bowel disease (IBD and the flora disequilibrium of Bacteroides. We performed a meta-analysis of the available data to provide a more precise estimate of the association between Bacteroides level in the gut and IBD. Methods. We searched PubMed/MEDLINE, EMBASE, Cochrane Library, Wiley Library, BIOSIS previews, Web of Science, CNKI, and ScienceDirect databases for published literature on IBD and gut microbiota from 1990 to 2016. Quality of all eligible studies was assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS. We compared the level of Bacteroides in IBD patients with that in a control group without IBD, different types of IBD patients, and IBD patients with active phase and in remission. Results. We identified 63 articles, 9 of which contained sufficient data for evaluation. The mean level of Bacteroides was significantly lower in Crohn’s disease (CD and ulcerative colitis (UC patients in active phase than in normal controls. The level of Bacteroides in remission CD and UC patients was much lower than patients in the control group. Bacteroides level was even lower in patients with CD and UC in active phase than in remission. Conclusions. This analysis suggests that lower levels of Bacteroides are associated with IBD, especially in active phase.

  8. Polaribacter gen. nov., with three new species, P. irgensii sp. nov., P. franzmannii sp. nov. and P. filamentus sp. nov., gas vacuolate polar marine bacteria of the Cytophaga-Flavobacterium-Bacteroides group and reclassification of 'Flectobacillus glomeratus' as Polaribacter glomeratus comb. nov

    Science.gov (United States)

    Gosink, J. J.; Woese, C. R.; Staley, J. T.

    1998-01-01

    Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobacterium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic. The closest taxonomically defined species by 16S rRNA sequence analysis is 'Flectobacillus glomeratus'. However, 'Flc. glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc. major. On the basis of phenotypic, genotypic and 16S rRNA sequence analyses we propose a new genus, Polaribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and Polaribacter filamentus strain 215 (ATCC 700397). P. filamentus is the type species of the genus. None of these species exhibits a cosmopolitan or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group. Additionally, we propose that 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. glomeratus, comb. nov.

  9. Repeated Dientamoeba fragilis infections: a case report of two families from Sydney, Australia

    Directory of Open Access Journals (Sweden)

    Damien Stark

    2009-11-01

    Full Text Available We report cases of two unrelated families who both presented with recurrent Dienta-moeba fragilis infections. Subsequent antimicrobial therapy resulted in the clearance of D. fragilis and total resolution of gastrointestinal symptoms in both families. This report highlights the potentially recurrent nature of D. fragilis infections and the need for laboratories to routinely test for this organism.

  10. Molecular Investigations of Bacteroides as Microbial Source Tracking Tools in Southeast Louisiana Watersheds

    Science.gov (United States)

    Schulz, C. J.; Childers, G. W.; Engel, A. S.

    2006-12-01

    Microbial Source Tracking (MST) is a developing field that is gaining increased attention. MST refers to a host of techniques that discriminates among the origins of fecal material found in natural waters from different sources (e.g. human, livestock, and wildlife) by using microbial indicator species with specificity to only certain host organisms. The development of species-specific molecular markers would allow for better evaluation of public health risks and tracking of nutrient sources impacting a watershed. Although several MST methods have been reported with varying levels of success, few offer general applicability for natural waters due to spatial and temporal constraints associated with these methods. One group of molecular MST markers that show promise for broad environmental applications are molecular 16S rDNA probes for Bacteroides. This method is based on 16S rDNA detection directly from environmental samples without the need for a preliminary cultivation step. In this study we have expanded previous sampling efforts to compile a database of over 1000 partial 16S rRNA Bacteroides genes retrieved from the fecal material of 15 different host species (human, cat, dog, pig, kangaroo). To characterize survival of Bacteroides outside of the host, survival time of the Bacteroides marker was compared to that of E.coli under varying natural environmental conditions (temperature and salinity). Bacteroides displayed a survival curve with shouldering and tailing similar to that of E.coli, but log reduction times differed with treatment. In summary, MST marker stability was identified within host species and the overall Bacteroides community structure correlated to host diet, suggesting that detection of a Bacteroides community could confidently identify fecal contamination point sources. Natural water samples from southeast Louisiana were collected for MST including the Tangipahoa River watershed where the source of fecal contamination has been hotly debated. The

  11. PREVALENCE OF DIENTAMOEBA FRAGILIS AMONG AN ORANG ASLI POPULATION IN RURAL MALAYSIA.

    Science.gov (United States)

    Anuar, Tengku Shahrul; Hasim, Liyana; Moktar, Norhayati; Salleh, Fatmah Md; Al-Mekhlafi, Hesham M

    2015-09-01

    Dientamoeba fragilis is a trichomonad parasite that can infect the gastrointestinal tract of humans causing gastrointestinal disease. Little is known about its epidemiology. We evaluated the prevalence of D. fragilis by conducting a cross sectional study of an Orang Asli population in rural Malaysia. We examined stool samples from 150 participants for D. fragilis using Wheatley's trichrome stain and collected demographic data from each participant using a structured questionnaire. Five participants (3.3%) had D. fragilis in their stool; four of these were aged population. Further studies are needed to determine the virulence, pathogenicity and mode of transmission of D. fragilis in the study population.

  12. DNA of Dientamoeba fragilis detected within surface-sterilized eggs of Enterobius vermicularis

    DEFF Research Database (Denmark)

    Röser, Dennis; Nejsum, Peter; Carlsgart, Anne Josefine;

    2013-01-01

    With no evidence of a cyst stage, the mode of transmission of Dientamoeba fragilis, an intestinal protozoon of common occurrence and suggested pathogenicity, is incompletely known. Numerous studies have suggested that eggs of intestinal nematodes, primarily Enterobius vermicularis (pinworm), can...... serve as vectors for D. fragilis, although attempts to culture D. fragilis from pinworm eggs have been unsuccessful and data from epidemiological studies on D. fragilis/pinworm co-infection have been conflicting. The aim of this study was to investigate whether we could detect D. fragilis DNA from...... pinworm eggs collected from routine diagnostic samples (cellophane tape) and surface-sterilised by hypochlorite. DNA was extracted from individual eggs and tested by PCR using D. fragilis- and E. vermicularis-specific primers; amplicons were sequenced for confirmation. In cellophane tape samples from 64...

  13. Linkage mapping in tetraploid willows: segregation of molecular markers and estimation of linkage phases support an allotetraploid structure for Salix alba x Salix fragilis interspecific hybrids.

    Science.gov (United States)

    Barcaccia, G; Meneghetti, S; Albertini, E; Triest, L; Lucchin, M

    2003-02-01

    Salix alba-Salix fragilis complex includes closely related dioecious polyploid species, which are obligate outcrossers. Natural populations of these willows and their hybrids are represented by a mixture of highly heterozygous genotypes sharing a common gene pool. Since nothing is known about their genomic constitution, tetraploidy (2n=4x=76) in willow species makes basic and applied genetic studies difficult. We have used a two-way pseudotestcross strategy and single-dose markers (SDMs) to construct the first linkage maps for both pistillate and staminate willows. A total of 242 amplified fragment length polymorphisms (AFLPs) and 50 selective amplifications of microsatellite polymorphic loci (SAMPL) markers, which showed 1:1 segregation in the F(1) mapping populations, were used in linkage analysis. In S. alba, 73 maternal and 48 paternal SDMs were mapped to 19 and 16 linkage groups covering 708 and 339 cM, respectively. In S. fragilis, 13 maternal and 33 paternal SDMs were mapped in six and 14 linkage groups covering 98 and 321 cM, respectively. For most cosegregation groups, a comparable number of markers linked in coupling and repulsion was identified. This finding suggests that most of chromosomes pair preferentially as occurs in allotetraploid species exhibiting disomic inheritance. The detection of 10 pairs of marker alleles from single parents showing codominant inheritance strengthens this hypothesis. The fact that, of the 1122 marker loci identified in the two male and female parents, the vast majority (77.5%) were polymorphic and as few as 22.5% were shared between parental species highlight that S. alba and S. fragilis genotypes are differentiated. The highly difference between S. alba- and S. fragilis-specific markers found in both parental combinations (on average, 65.3 vs 34.7%, respectively) supports the (phylogenetic) hypothesis that S. fragilis is derived from S. alba-like progenitors.

  14. Viability of Rhizobium bacteroids isolated from soybean nodule protoplasts.

    Science.gov (United States)

    Gresshoff, P M; Rolfe, B G

    1978-01-01

    Bacteriods isolated from protoplasts taken from Rhizobium japonicum induced root nodule of Glycine max L. showed complete viability when plated onto a conventional rhizobial growth medium supplemented with 0.2 M Mannitol. The same medium but without extra mannitol resulted in the absence of colony formation. The protoplast isolation method eliminated the possibility of contaminant bacteria from infection threads to be scored. The redifferentiated bacteroid clones have the same genetical characteristics as the orginal inoculum strain. This and other recent findings of bacteroid viability are discussed in the light of the existing belief that bacteroids are non-viable.

  15. [The first metronidazole-resistant Bacteroides species isolated at Marmara University Hospital: Bacteroides thetaiotaomicron].

    Science.gov (United States)

    Toprak Ülger, Nurver; Sayın, Elvan; Soyad, Ad; Dane, Faysal; Söyletir, Güner

    2013-10-01

    Bacteroides species, the predominant constituents of the human intestinal microbiota can cause serious intraabdominal and postoperative wound infections and bacteremia. Moreover, these bacteria are more resistant to antimicrobial agents than the other anaerobes. The limited number of the antimicrobials, such as carbapenems, beta-lactam/beta-lactamase inhibitors and nitroimidazoles are highly effective in eliminating Bacteroides. However, a few metronidazole-resistant isolates have been reported from several countries recently. The nim genes (nim A-G) are suggested to be responsible for the majority of the metronidazole resistance. Here, we describe a metronidazole-resistant Bacteroides thetaiotaomicron isolated from a blood culture. A gram-negative obligate anaerobic rod was isolated from the postoperative 5th day blood culture of a 62-year-old male patient with adenocarcinoma of the pancreas head. The strain was identified as B.thetaiotaomicron by using a combination of conventional tests and commercially available biochemical kits. Antimicrobial susceptibility testing was performed by agar dilution method. The resistance genes were investigated by means of PCR using specific primer pairs for nim gene. The purified PCR product was sequenced and analyzed by comparison of the consensus sequences with GenBank sequences. The MIC for metronidazole was 16 mg/L. Although the strain was intermediate according the CLSI criteria, it was resistant (> 4 mg/L) according to EUCAST criteria. The isolate was nim gene positive, and nucleotide sequencing of the PCR product shared 100% similarity with nimE gene (emb |AM042593.1 |). On the other hand the isolate was susceptible to carbapenems and sulbactam-ampicillin. Following administration of ampicillin-sulbactam, the patient's fever disappeared after 24 hours. The clinical condition improved considerably and he was discharged at day 8. The patient was followed up at the medical oncology clinic; however he died due to disease

  16. Bacteremia with Bacteroides pyogenes after a cat bite

    DEFF Research Database (Denmark)

    Madsen, Ida Ringsborg; Justesen, Ulrik Stenz

    2011-01-01

    Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite.......Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite....

  17. Bacteroides gingivalis and Bacteroides intermedius recognize different sites on human fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, M.S.; Allen, R.D.; Bounelis, P.; Switalski, L.M.; Hook, M. (Univ. of Alabama, Birmingham (USA))

    1990-02-01

    Bacteroides (Porphyromonas) gingivalis and Bacteroides (Porphyromonas) intermedius have been implicated in the etiology of human periodontal diseases. These organisms are able to bind and degrade human fibrinogen, and these interactions may play a role in the pathogenesis of periodontal disease. In attempts to map the bacterial binding sites along the fibrinogen molecule, we have found that strains of B. gingivalis and B. intermedius, respectively, recognize spatially distant and distinct sites on the fibrinogen molecule. Isolated reduced and alkylated alpha-, beta-, and gamma-fibrinogen chains inhibited binding of 125I-fibrinogen to both Bacteroides species in a concentration-dependent manner. Plasmin fragments D and to some extent fragment E, however, produced a concentration-dependent inhibition of 125I-fibrinogen binding to B. intermedius strains but did not affect binding of 125I-fibrinogen to B. gingivalis strains. Radiolabeled fibrinogen chains and fragments were compared with 125I-fibrinogen with respect to specificity and reversibility of binding to bacteria. According to these criteria, gamma chain most closely resembled the native fibrinogen molecule in behavior toward B. gingivalis strains and fragments D most closely resembled fibrinogen in behavior toward B. intermedius strains. The ability of anti-human fibrinogen immunoglobulin G (IgG) to inhibit binding of 125I-fibrinogen to B. intermedius strains was greatly reduced by absorbing the IgG with fragments D. Absorbing the IgG with fragments D had no effect on the ability of the antibody to inhibit binding of 125I-fibrinogen to B. gingivalis strains. A purified staphylococcal fibrinogen-binding protein blocked binding of 125I-fibrinogen to B. intermedius strains but not to B. gingivalis strains.

  18. Cloning and expression of Kluyveromyces fragilis LAC4 gene

    Institute of Scientific and Technical Information of China (English)

    霍克克; 李育阳

    1995-01-01

    The genomic library of Kluyveromyces fragilis was constructed in E.coli TG1,and 5β-galactosidase gene(LAC4)clones have been obtained from the library by complementation of theKluyveromyces lactis lac4-8 mutation.The studies on the structure and the function of the LAC4 gene revealedthat(i)the gene can also complement E.coli lacZ mutation;(ii)the physical map of the K.fragilis LAC4gene was very similar to that of K.lactis;(iii)the β-galactosidase levels expressed by the clone strains weremuch higher than that expressed by the original strain;(iv)the variation of the β-galactosidase level of differ-ent clone strains induced by lactose or galactose was related to the retained degree of the 5’ flanking region ofLAC4 gene,suggesting that there migth he a lactose specific transcription activating element in the region.

  19. Haploid Barley from the Intergeneric Cross Hordeum vulgare x Psathyrostachys fragilis

    DEFF Research Database (Denmark)

    Bothmer, Roland; Jacobsen, Niels; Bagger Jørgensen, Rikke;

    1984-01-01

    The intergeneric hybrid Hordeum vulgare x Psathyrostachys fragilis was fairly easily obtained. During each growing season the intermediate, perennial hybrid yielded haploid tillers of H. vulgare. Late in one season few, hybrid tillers headed. The morphology, cytology and enzymatic patterns...

  20. Is the treatment of Enterobius vermicularis co-infection necessary to eradicate Dientamoeba fragilis infection?

    Directory of Open Access Journals (Sweden)

    José A. Boga

    2016-08-01

    Conclusions: Co-infection with E. vermicularis may act as a factor favoring D. fragilis infection by preventing eradication measures. This suggests that both parasites should be treated simultaneously.

  1. Genome Sequence of Youngiibacter fragilis, the Type Strain of the Genus Youngiibacter

    OpenAIRE

    Wawrik, Colin B.; Callaghan, Amy V.; Stamps, Blake W.; Wawrik, Boris

    2014-01-01

    The genome of Youngiibacter fragilis, the type strain of the newly described genus Youngiibacter, was sequenced. The genome consists of 3.996 Mb, with a G+C content of 46.6 mol%. Y. fragilis originates from coal-bed methane-produced water and may provide insight into the microbiological basis of biogas production in coal beds.

  2. Genome Sequence of Youngiibacter fragilis, the Type Strain of the Genus Youngiibacter.

    Science.gov (United States)

    Wawrik, Colin B; Callaghan, Amy V; Stamps, Blake W; Wawrik, Boris

    2014-01-23

    The genome of Youngiibacter fragilis, the type strain of the newly described genus Youngiibacter, was sequenced. The genome consists of 3.996 Mb, with a G+C content of 46.6 mol%. Y. fragilis originates from coal-bed methane-produced water and may provide insight into the microbiological basis of biogas production in coal beds.

  3. Cytologic and Genetic Characteristics of Endobiotic Bacteria and Kleptoplasts of Virgulinella fragilis (Foraminifera).

    Science.gov (United States)

    Tsuchiya, Masashi; Toyofuku, Takashi; Uematsu, Katsuyuki; Brüchert, Volker; Collen, John; Yamamoto, Hiroyuki; Kitazato, Hiroshi

    2015-01-01

    The benthic foraminifer Virgulinella fragilis Grindell and Collen 1976 has multiple putative symbioses with both bacterial and kleptoplast endobionts, possibly aiding its survival in environments from dysoxia (5-45 μmol-O2 /L) to microxia (0-5 μmol-O2 /L) and in the dark. To clarify the origin and function of V. fragilis endobionts, we used genetic analyses and transmission electron microscope observations. Virgulinella fragilis retained δ-proteobacteria concentrated at its cell periphery just beneath the cell membranes. Unlike another foraminifer Stainforthia spp., which retains many bacterial species, V. fragilis has a less variable bacterial community. This suggests that V. fragilis maintains a specific intracellular bacterial flora. Unlike the endobiotic bacteria, V. fragilis klepto-plasts originated from various diatom species and are found in the interior cytoplasm. We found evidence of both retention and digestion of kleptoplasts, and of fragmentation of the kleptoplastid outer membrane that likely facilitates transport of kleptoplastid products to the host. Accumulations of mitochondria were observed encircling endobiotic bacteria. It is likely that the bacteria use host organic material for carbon oxidation. The mitochondria may use oxygen available around the δ-proteobacteria and synthesize adenosine triphosphate, perhaps for sulfide oxidation.

  4. Organic Acid Metabolism by Isolated Rhizobium japonicum Bacteroids

    Science.gov (United States)

    Stovall, Iris; Cole, Michael

    1978-01-01

    Rhizobium japonicum bacteroids isolated from soybean (Glycine max L.) nodules oxidized 14C-labeled succinate, pyruvate, and acetate in a manner consistent with operation of the tricarboxylic acid cycle and a partial glyoxylate cycle. Substrate carbon was incorporated into all major cellular components (cell wall + membrane, nucleic acids, and protein). PMID:16660386

  5. Characteristics of bacteroids in indeterminate nodules of the leguminous tree Leucaena glauca.

    Science.gov (United States)

    Ishihara, Hironobu; Koriyama, Hiroki; Osawa, Atsushi; Zehirov, Grigor; Yamaura, Masatoshi; Kucho, Ken-ichi; Abe, Mikiko; Higashi, Shiro; Kondorosi, Eva; Mergaert, Peter; Uchiumi, Toshiki

    2011-01-01

    Rhizobia establish symbiosis with legumes. Bacteroids in indeterminate nodules of Inverted Repeat Lacking Clade (IRLC) legumes undergo terminal differentiation caused by Nodule-specific Cysteine-Rich peptides (NCRs). Microscopic observations of bacteroids and the detection of NCRs in indeterminate nodules of the non-IRLC legume Leucaena glauca were performed. A portion of the bacteroids showed moderate cell elongation, loss of membrane integrity, and multiple nucleoids. The symbiosome contained multiple bacteroids and NCR-like peptides were not detectable. These results indicate that bacteroid differentiation in L. glauca is different from that in IRLC legumes although both hosts form indeterminate nodules.

  6. Effect of the corn silage to grass silage ratio and feed particle size of diets for ruminants on the ruminal Bacteroides-Prevotella community in vitro.

    Science.gov (United States)

    Witzig, M; Boguhn, J; Kleinsteuber, S; Fetzer, I; Rodehutscord, M

    2010-08-01

    This study examined whether different corn silage to grass silage ratios in ruminant rations and different grinding levels of the feed affect the composition of the ruminal Bacteroides-Prevotella community in vitro. Three diets, composed of 10% soybean meal as well as of different corn silage and grass silage proportions, were ground through 1mm or 4mm screened sieves and incubated in a semi-continuous rumen simulation system. On day 14 of the incubation microbes were harvested by centrifugation from the liquid effluent of fermenter vessels. Microbial DNA was extracted for single strand conformation polymorphism (SSCP) analysis of 16S rRNA genes followed by sequencing of single SSCP bands. Fluorescence in situ hybridization (FISH) and real-time quantitative (q) PCR were used to quantify differences in the relative abundance of Bacteroides-Prevotella and Prevotella bryantii. SSCP profiles revealed a significant influence of the forage source as well as of the feed particle size on the community structure of the Bacteroides-Prevotella group. Different, phylogenetically distinct, so far uncultured Prevotella species were detected by sequence analysis of several treatment-dependent occurring SSCP bands indicating different nutritional requirements of these organisms for growth. No quantitative differences in the occurrence of Bacteroides-Prevotella-related species were detected between diets by FISH with probe BAC303. However, real-time qPCR data revealed a higher abundance of P. bryantii with increasing grass silage to corn silage ratio, thus again indicating changes within the community composition of the Bacteroides-Prevotella group. As P. bryantii possesses high proteolytic activity its higher abundance may have been caused by the higher contents of crude protein in the grass silage containing diets. To conclude, results of this study show an influence of the forage source on the ruminal community of Bacteroides-Prevotella. Furthermore, they suggest an effect of

  7. Lichens promote flowering Opuntia fragilis in west-central Wisconsin

    Science.gov (United States)

    Bennett, J.P.; Bornar, C.R.; Harrington, C.A.

    2003-01-01

    Clumps of the cactus Opuntia fragilis growing in association with mats of the lichens Cladina mitis, Cladina rangiferina and a spikemoss, Selaginella rupestris, were discovered in an agricultural field in Pepin County, Wisconsin, that had been abandoned for over 50 y. The association appeared to be beneficial to the cactus, which flowered almost exclusively in the presence of lichens. Of 294 cactus clumps examined in 2001, 127 grew in the presence of lichen mats and, of these, 24 flowered, producing 91 flowers, while none of the cacti growing in the absence of lichens flowered. In 2002, 19 out of 265 cactus clumps flowered, all but one in the presence of lichens. All sizes of cacti in the presence of lichens flowered and the probability of flowering increased with cactus size. In addition, the cacti that flowered had cladodes that were on average 19% heavier than those of cacti that did not flower. The presence of lichens lowered summer soil temperatures 2a??4 C compared to soil temperatures in the absence of lichens. Cooler soil temperatures conserve soil moisture better, which may enhance flowering in these cacti.

  8. Identification of feces by detection of Bacteroides genes.

    Science.gov (United States)

    Nakanishi, Hiroaki; Shojo, Hideki; Ohmori, Takeshi; Hara, Masaaki; Takada, Aya; Adachi, Noboru; Saito, Kazuyuki

    2013-01-01

    In forensic science, the identification of feces is very important in a variety of crime investigations. However, no sensitive and simple fecal identification method using molecular biological techniques has been reported. Here, we focused on the fecal bacteria, Bacteroides uniformis, Bacteroides vulgatus and Bacteroides thetaiotaomicron, and developed a novel fecal identification method by detection of the gene sequences specific to these bacteria in various body (feces, blood, saliva, semen, urine, vaginal fluids and skin surfaces) and forensic (anal adhesions) specimens. Bacterial gene detection was performed by real-time PCR using a minor groove binding probe to amplify the RNA polymerase β-subunit gene of B. uniformis and B. vulgatus, and the α-1-6 mannanase gene of B. thetaiotaomicron. At least one of these bacteria was detected in the feces of 20 donors; the proportions of B. uniformis, B. vulgatus and B. thetaiotaomicron were 95, 85 and 60%, respectively. Bacteroides vulgatus was also detected in one of six vaginal fluid samples, but B. thetaiotaomicron and B. uniformis were not detected in body samples other than feces. Further, we applied this method to forensic specimens from 18 donors. Eighteen anal adhesions also contained at least one of three bacteria; B. uniformis, B. vulgatus and B. thetaiotaomicron were detected in 89, 78 and 56%, respectively, of the specimens. Thus, these bacteria were present at a high frequency in the fecal and forensic specimens, while either B. uniformis or B. vulgatus was detected in all samples. Therefore, B. uniformis and B. vulgatus represent more appropriate target species than B. thetaiotaomicron for the identification of fecal material. If B. vulgatus and/or B. uniformis are detected, it is likely that the sample contains feces. Taken together, our results suggest that the use of molecular biological techniques will aid the detection of feces in forensic practice, although it is possible that the samples contained

  9. Production of a fecal mutagen by Bacteroides spp.

    OpenAIRE

    Van Tassel, R L; MacDonald, D K; Wilkins, T D

    1982-01-01

    Forty species of anaerobes were screened for the ability to produce an ether-extractable mutagen which is present in the feces of 15 to 20% of individuals in populations at high risk for colon cancer. This mutagen can be produced in vitro by incubating the feces of these individuals anaerobically or by supplementing anaerobic broths with methanol extracts of the feces and incubating them with a dilute fecal inoculum. Of the anaerobes screened, strains of five species of Bacteroides (B. thetai...

  10. Could be the swine responsible of transmission to the humans of Dientamoeba fragilis infection?

    Directory of Open Access Journals (Sweden)

    Daniele Crotti

    2011-03-01

    Full Text Available Dientamoeba fragilis, atypical protozoon because “flagellate without flagella” but amoeba-like, of whom we know only the trophozoitic stage (an so its brittleness outside intestinal tract, is a frequent responsible of intestinal human infections, worldwide, and some authors relate that D. fragilis is the most frequent protozoon and parasite that can infects humans. Actually we don’t know a sure potential “reservoir” in animals who are strictly in contact with humans, and it is difficult to understand its epidemiological chain, otherwise the transmissions to humans and from humans to humans. For all these reasons we performed another study on subjects of swine breedings, and among people who work in these breedings, that are in direct contact or not with pigs. Using standardized methodologies, we analyzed 224 faecal specimens of swine and 15 human specimens.We use for identification of D. fragilis the Giemsa stain.These were the results: D. fragilis was observed in 50.9% of pigs and 20% among humans (30% in workers strictly in contact with breedings and pigs, 0% in familiars or other without a closed contact with swines. Other commensal protozoa were observed with variable associations, but in this article we want to analyze the possible transmission from this pigs to humans (and for us this protozoon is undoubtedly a “reservoir” of D. fragilis for humans, and underline two aspects: for the research of this protozoon, standard procedures area mandatory, with a permanent stain, as Giemsa stain, is necessary, and in all humans with various intestinal infections or troubles, particularly “irritable bowel syndrome” (or similar ones, the specimens must be analyzed for D. fragilis. At least we think that in the near future molecular studies are important for confirming this our observations, and for verifying eventual and probable differences inside genotypes of this very suggestive protozoon, that until now present not rarely

  11. Dientamoeba fragilis: initial evidence of pathogenicity in the western lowland gorilla (Gorilla gorilla gorilla).

    Science.gov (United States)

    Lankester, Felix; Kiyang, John Anyam; Bailey, Wendi; Unwin, Steve

    2010-06-01

    A 7-yr-old female western lowland gorilla (Gorilla gorilla gorilla) shared an enclosure with 10 other gorillas at the Limbe Wildlife Centre (LWC), a wildlife rehabilitation centre in Cameroon. The gorilla had been living at the LWC for more than 6 yr prior to the exhibition of irritable bowel syndrome (IBS)-like clinical signs. The gorilla improved dramatically after metronidazole therapy. The report suggests that metronidazole was effective because it eliminated the protozoa, Dientamoeba fragilis. Dientamoeba fragilis should be considered on the differential diagnosis list of any captive gorilla with IBS-like symptoms.

  12. Dientamoeba fragilis - a Commensal in Children in Danish Day Care Centers

    DEFF Research Database (Denmark)

    Jokelainen, Pikka; Hebbelstrup Jensen, Betina; Andreassen, Bente Utoft

    2017-01-01

    Dientamoeba fragilis is an intestinal protozoan of debated clinical significance. Here, we present cross-sectional and longitudinal observations on D. fragilis in children aged 0-6 years from a 1-year multi-day-care-center cohort study set in Copenhagen, Denmark. The inclusion period for the cohort...... factors (age, gender, having siblings, having domestic animals at home, having had infant colic, recent history of intake of antibiotics, and recent history of travel abroad) as well as six reported symptoms (lack of appetite, nausea, vomiting, abdominal pain, weight loss, and diarrhea) and testing...

  13. Study of physiological properties of Kluyveromyces fragilis: consequences on the production of SCP from whey

    Energy Technology Data Exchange (ETDEWEB)

    Moulin, G.; Malige, B.; Galzy, P.

    The production of single cell proteins (SCP) from whey, is performed with continuous culture of Kluyveromyces fragilis. This strain, does not show any crabtree effect, but the Pasteur effect is very strong; the fermentative activity is never absent even when strong aeration is present. So in all cases, alcohol is present in the medium. This observation can explain why the yield in an industrial production with an appropriate mixture culture is always higher than the yield in pure culture of Kluyveromyces fragilis. (Refs. 10).

  14. Comparison of the Giemsa C-banded karyotypes of the three subspecies of Psathyrostachys fragilis, subspp. villosus (2x), secaliformis (2x, 4x), and fragilis (2x) (Poaceae), with notes on chromosome pairing

    DEFF Research Database (Denmark)

    Linde-Laursen, I.; Baden, C.

    1994-01-01

    The karyotypes of diploid P. fragilis subsp. villosus (2n = 2x = 14) and tetraploid subsp. secaliformis (2n = 4x = 28) were studied by Giemsa C- and N-banding, and AgNO3 staining and compared with the karyotype of subsp. fragilis (2x). The complements of subsp. villosus and subsp. fragilis were...... in chromosome morphology and C-banding patterns identified homology of all chromosomes of subsp. villosus, but for 12 pairs only in subsp. secaliformis. Between plants, reliable identification of homology and homoeology (subsp. secaliformis) was possible only for the SAT-chromosomes and the shortest...

  15. Draft Genome Sequence of the Probiotic Yeast Kluyveromyces marxianus fragilis B0399.

    Science.gov (United States)

    Quarella, Sara; Lovrovich, Paola; Scalabrin, Simone; Campedelli, Ilenia; Backovic, Ana; Gatto, Veronica; Cattonaro, Federica; Turello, Alessandro; Torriani, Sandra; Felis, Giovanna E

    2016-09-01

    Here, we report the draft genome sequence of Kluyveromyces marxianus fragilis B0399, the first yeast approved as a probiotic for human consumption not belonging to the genus Saccharomyces The genome is composed of 8 chromosomes, with a total size of 11.44 Mb, including mitochondrial DNA.

  16. Is paromomycin the drug of choice for eradication of Dientamoeba fragilis in adults?

    NARCIS (Netherlands)

    J.J. van Hellemond (Jaap); N. Molhoek (Nicky); R. Koelewijn (Rob); P.J. Wismans (Pieter); P.J.J. van Genderen (Perry)

    2012-01-01

    textabstractDientamoeba fragilis is a debated protozoan parasite that is often detected in stools of patients with chronic gastro-intestinal complaints. A retrospective follow-up study of a large cohort of patients was performed to better understand the natural course of the infection and possible t

  17. Phylogeographic structure and northward range expansion in the barnacle Chthamalus fragilis

    Directory of Open Access Journals (Sweden)

    Annette F. Govindarajan

    2015-04-01

    Full Text Available The barnacle Chthamalus fragilis is found along the US Atlantic seaboard historically from the Chesapeake Bay southward, and in the Gulf of Mexico. It appeared in New England circa 1900 coincident with warming temperatures, and is now a conspicuous member of rocky intertidal communities extending through the northern shore of Cape Cod, Massachusetts. The origin of northern C. fragilis is debated. It may have spread to New England from the northern end of its historic range through larval transport by ocean currents, possibly mediated by the construction of piers, marinas, and other anthropogenic structures that provided new hard substrate habitat. Alternatively, it may have been introduced by fouling on ships originating farther south in its historic distribution. Here we examine mitochondrial cytochrome c oxidase I sequence diversity and the distribution of mitochondrial haplotypes of C. fragilis from 11 localities ranging from Cape Cod, to Tampa Bay, Florida. We found significant genetic structure between northern and southern populations. Phylogenetic analysis revealed three well-supported reciprocally monophyletic haplogroups, including one haplogroup that is restricted to New England and Virginia populations. While the distances between clades do not suggest cryptic speciation, selection and dispersal barriers may be driving the observed structure. Our data are consistent with an expansion of C. fragilis from the northern end of its mid-19th century range into Massachusetts.

  18. Symptoms and treatment of Dientamoeba fragilis infection in children, a retrospective study

    NARCIS (Netherlands)

    Schure, Janna M A Ter; de Vries, Marrit; Weel, Jan F L; van Roon, Eric N; Faber, Tina E

    2013-01-01

    INTRODUCTION: Dientamoeba fragilis infection in children is common, and its incidence has increased since the introduction of more sensitive molecular techniques. There is no consensus on the optimal treatment. Current medical practice in the Netherlands is to treat symptomatic children with clioqui

  19. Bacteroides isolated from four mammalian hosts lack host-specific 16S rRNA gene phylogeny and carbon and nitrogen utilization patterns.

    Science.gov (United States)

    Atherly, Todd; Ziemer, Cherie J

    2014-04-01

    One-hundred-and-three isolates of Bacteroides ovatus, B. thetaiotaomicron, and B. xylanisolvens were recovered from cow, goat, human, and pig fecal enrichments with cellulose or xylan/pectin. Isolates were compared using 16S rRNA gene sequencing, repetitive sequence-based polymerase chain reaction (rep-PCR), and phenotypic microarrays. Analysis of 16S rRNA gene sequences revealed high sequence identity in these Bacteroides; with distinct phylogenetic groupings by bacterial species but not host origin. Phenotypic microarray analysis demonstrated these Bacteroides shared the ability to utilize many of the same carbon substrates, without differences due to species or host origin, indicative of their broad carbohydrate fermentation abilities. Limited nitrogen substrates were utilized; in addition to ammonia, guanine, and xanthine, purine derivatives were utilized by most isolates followed by a few amino sugars. Only rep-PCR analysis demonstrated host-specific patterns, indicating that genomic changes due to coevolution with host did not occur by mutation in the 16S rRNA gene or by a gain or loss of carbohydrate utilization genes within these Bacteroides. This is the first report to indicate that host-associated genomic differences are outside of 16S rRNA gene and carbohydrate utilization genes and suggest conservation of specific bacterial species with the same functionality across mammalian hosts for this Bacteroidetes clade.

  20. Bacteriophages infecting Bacteroides as a marker for microbial source tracking.

    Science.gov (United States)

    Jofre, Joan; Blanch, Anicet R; Lucena, Francisco; Muniesa, Maite

    2014-05-15

    Bacteriophages infecting certain strains of Bacteroides are amid the numerous procedures proposed for tracking the source of faecal pollution. These bacteriophages fulfil reasonably well most of the requirements identified as appropriate for a suitable marker of faecal sources. Thus, different host strains are available that detect bacteriophages preferably in water contaminated with faecal wastes corresponding to different animal species. For phages found preferably in human faecal wastes, which are the ones that have been more extensively studied, the amounts of phages found in waters contaminated with human fecal samples is reasonably high; these amounts are invariable through the time; their resistance to natural and anthropogenic stressors is comparable to that of other relatively resistant indicator of faecal pollution such us coliphages; the abundance ratios of somatic coliphages and bacteriophages infecting Bacteroides thetaiotaomicron GA17 are unvarying in recent and aged contamination; and standardised detection methods exist. These methods are easy, cost effective and provide data susceptible of numerical analysis. In contrast, there are some uncertainties regarding their geographical stability, and consequently suitable hosts need to be isolated for different geographical areas. However, a feasible method has been described to isolate suitable hosts in a given geographical area. In summary, phages infecting Bacteroides are a marker of faecal sources that in our opinion merits being included in the "toolbox" for microbial source tracking. However, further research is still needed in order to make clear some uncertainties regarding some of their characteristics and behaviour, to compare their suitability to the one of emerging methods such us targeting Bacteroidetes by qPCR assays; or settling molecular methods for their determination.

  1. Dientamoeba fragilis detection in suid populations: an emerging zoonosis hypothesized in Central Italy

    Directory of Open Access Journals (Sweden)

    Daniele Crotti

    2012-09-01

    Full Text Available Dientamoeba fragilis (D. fragilis is a worldwide distributed protozoan parasite; it is pathogenic for humans. A wide spectrum of gastrointestinal symptoms has been described in infected patients: diarrhoea, flatulence, abdominal pains, colic and weight loss. However, asymptomatic infection has been also described. D. fragilis is still not well known; no cystic stage has been demonstrated and only the trophozoites are detected in stool samples. For identifying this typically more often binucleate protozoan, is necessary to perform permanent stain (eg. Giemsa on fresh stool specimens. This protozoan is extremely difficult to cultivate but molecular techniques such as the Polymerase Chain Reaction offer promise as a means of diagnosing infection. In five years time (2006-2010, faecal samples were collected from pigs housed in farrow-to-finish herds (494 samples, splitted in three different categories: sows, growers, finishing pigs and from hunted or slaughtered wild boars (87 samples. Simultaneously, the study was undertaken on human faeces (17 samples to evaluate the presence of D. fragilis in pig breeders. All samples were collected directly from the rectum, cooled and sent to the laboratory where they were examined for D. fragilis by direct microscopic examination. The fresh faecal smears were stained with a 10% Giemsa solution in distilled water for 30 min. Biomolecular investigations (TaqMan real-time PCR which targets the 5.8S rRNA, nested PCR for the 18S rRNA, nested PCR for the internal transcribed spacer 1 region were carried out on 38 pigs and 17 pig breeders specimens. The microscopic examination of the fresh fecal smears revealed positivity in 277 domestic pigs, corresponding to 56.07%. In particular higher positivity was observed on youngest animal (76.57%, while oldest or mature pigs recorded an important decreasing of positivity according the age (Table 1. Concerning wild boars, we revealed positivity in 35 animals (40.22%. Among

  2. Purification of microbial b-galactosidase from Kluyveromyces fragilis by bioaffinity partitioning

    Directory of Open Access Journals (Sweden)

    Silva Maria Estela da

    1999-01-01

    Full Text Available This work investigated the partitioning of b-galactosidase from Kluyveromyces fragilis in aqueous two-phase systems (ATPS by bioaffinity. PEG 4000 was chemically activated with thresyl chloride, and the biospecific ligand p-aminophenyl 1-thio-b-D-galactopyranoside (APGP was attached to the activated PEG 4000. A new two-step method for extraction and purification of the enzyme b-galactosidase from Kluyveromyces fragilis was developed. In the first step, a system composed of 6% PEG 4000-APGP and 8% dextran 505 was used, where b-galactosidase was strongly partitioned to the top phase (K = 2,330. In the second step, a system formed of 13% PEG-APGP and 9% phosphate salt was used to revert the value of the partition coefficient of b-galactosidase (K = 2 x 10-5 in order to provide the purification and recovery of 39% of the enzyme in the bottom salt-rich phase.

  3. Physiological and proteomic responses of different willow clones (Salix fragilis x alba) exposed to dredged sediment contaminated by heavy metals.

    Science.gov (United States)

    Evlard, Aricia; Sergeant, Kjell; Ferrandis, Salvador; Printz, Bruno; Renaut, Jenny; Guignard, Cedric; Paul, Roger; Hausman, Jean-Francois; Campanella, Bruno

    2014-01-01

    High biomass producing species are considered as tools for remediation of contaminated soils. Willows (Salix spp.) are prominent study subjects in this regard. In this study, different willow clones (Salix fragilis x alba) were planted on heavy-metal polluted dredging sludge. A first objective was assessment of the biomass production for these clones. Using a Gupta statistic, four clones were identified as high biomass producers (HBP). For comparison, a group of four clones with lowest biomass production were selected (LBP). A second objective was to compare metal uptake as well as the physiological and proteomic responses of these two groups. All these complementary data's allow us to have a better picture of the health of the clones that would be used in phytoremediation programs. Cd, Zn, and Ni total uptake was higher in the HBPs but Pb total uptake was higher in LBPs. Our proteomic and physiological results showed that the LBPs were able to maintain cellular activity as much as the HBPs although the oxidative stress response was more pronounced in the LBPs. This could be due to the high Pb content found in this group although a combined effect of the other metals cannot be excluded.

  4. Susceptibility of Bacteroides nodosus to various antimicrobial agents.

    Science.gov (United States)

    Gradin, J L; Schmitz, J A

    1983-08-15

    The susceptibility of 18 strains of Bacteroides nodosus to 21 antimicrobial agents was tested in vitro. Penicillin was the most effective antibiotic tested. Other antibiotics tested, in order of relative efficacy, were cefamandole, clindamycin, tetracycline, chloramphenicol, erythromycin, sodium cefoxitin, tylosin tartrate, nitrofurazone, tinidazole, and dihydrostreptomycin sulfate. Tests of solutions of 4 antibiotics in 70% ethanol indicated that ethanol served primarily as a diluent and did not contribute substantially to the curative effect of such topical medications on foot rot lesions in sheep. Of the chemicals commonly used in foot baths for treatment of ovine foot rot, copper sulfate was most effective, followed by zinc sulfate, then formalin. Several commercial disinfectants and iodine were quite effective against B nodosus, whereas 5.25% sodium hypochlorite and 70% ethanol alone were relatively ineffective.

  5. Persistence of Bacteroides ovatus under simulated sunlight irradiation

    KAUST Repository

    Dong, Shengkun

    2014-07-04

    Background: Bacteroides ovatus, a member of the genus Bacteroides, is considered for use in molecular-based methods as a general fecal indicator. However, knowledge on its fate and persistence after a fecal contamination event remains limited. In this study, the persistence of B. ovatus was evaluated under simulated sunlight exposure and in conditions similar to freshwater and seawater. By combining propidium monoazide (PMA) treatment and quantitative polymerase chain reaction (qPCR) detection, the decay rates of B. ovatus were determined in the presence and absence of exogenous photosensitizers and in salinity up to 39.5 parts per thousand at 27°C. Results: UVB was found to be important for B. ovatus decay, averaging a 4 log10 of decay over 6 h of exposure without the presence of extracellular photosensitizers. The addition of NaNO2, an exogenous sensitizer producing hydroxyl radicals, did not significantly change the decay rate of B. ovatus in both low and high salinity water, while the exogenous sensitizer algae organic matter (AOM) slowed down the decay of B. ovatus in low salinity water. At seawater salinity, the decay rate of B. ovatus was slower than that in low salinity water, except when both NaNO2 and AOM were present. Conclusion: The results of laboratory experiments suggest that if B. ovatus is released into either freshwater or seawater environment in the evening, 50% of it may be intact by the next morning; if it is released at noon, only 50% may be intact after a mere 5 min of full spectrum irradiation on a clear day. This study provides a mechanistic understanding to some of the important environmental relevant factors that influenced the inactivation kinetics of B. ovatus in the presence of sunlight irradiation, and would facilitate the use of B. ovatus to indicate the occurrence of fecal contamination.

  6. Pyruvate Is Synthesized by Two Pathways in Pea Bacteroids with Different Efficiencies for Nitrogen Fixation▿

    OpenAIRE

    Mulley, Geraldine; Lopez-Gomez, Miguel; Zhang, Ye; Terpolilli, Jason; Prell, Jurgen; Finan, Turlough; Poole, Philip

    2010-01-01

    Nitrogen fixation in legume bacteroids is energized by the metabolism of dicarboxylic acids, which requires their oxidation to both oxaloacetate and pyruvate. In alfalfa bacteroids, production of pyruvate requires NAD+ malic enzyme (Dme) but not NADP+ malic enzyme (Tme). However, we show that Rhizobium leguminosarum has two pathways for pyruvate formation from dicarboxylates catalyzed by Dme and by the combined activities of phosphoenolpyruvate (PEP) carboxykinase (PckA) and pyruvate kinase (...

  7. Clinical and microbiological features of dientamoebiasis in patients suspected of suffering from a parasitic gastrointestinal illness: A comparison of Dientamoeba fragilis and Giardia lamblia infections

    NARCIS (Netherlands)

    O. Vandenberg; R. Peek; H. Souayah; A. Dediste; M. Buset; R. Scheen; P. Retore; G. Zissis; T. van Gool

    2006-01-01

    Objectives: To describe the clinical and microbiological features of Dientomoeba fragilis and Giordia lamblia infected patients, and to analyze the genetic variation of D. fragilis strains. Methods: For a period of two years, all stool samples collected from patients suspected of having a parasitic

  8. Microbial enterotypes, inferred by the prevotella-to-bacteroides ratio, remained stable during a 6-month randomized controlled diet intervention with the new nordic diet

    DEFF Research Database (Denmark)

    Roager, Henrik Munch; Licht, Tine Rask; Poulsen, Sanne;

    2014-01-01

    with central obesity and components of metabolic syndrome could be grouped into two discrete groups simply by their relative abundance of Prevotella spp. divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis. Furthermore, we showed that these groups remained stable during a 6-month......, controlled dietary intervention, where the effect of consuming a diet in accord with the new Nordic diet (NND) recommendations as opposed to consuming the average Danish diet (ADD) on the gut microbiota was investigated. In this study, subjects (with and without stratification according to P/B ratio) did...

  9. Bacteroides dorei dominates gut microbiome prior to autoimmunity in Finnish children at high risk for type 1 diabetes.

    Directory of Open Access Journals (Sweden)

    Austin G Davis-Richardson

    2014-12-01

    Full Text Available The incidence of the autoimmune disease, type 1 diabetes (T1D, has increased dramatically over the last half century in many developed countries and is particularly high in Finland and other Nordic countries. Along with genetic predisposition, environmental factors are thought to play a critical role in this increase. As with other autoimmune diseases, the gut microbiome is thought to play a potential role in controlling progression to T1D in children with high genetic risk, but we know little about how the gut microbiome develops in children with high genetic risk for T1D. In this study, the early development of the gut microbiomes of 76 children at high genetic risk for T1D was determined using high-throughput 16S rRNA gene sequencing. Stool samples from children born in the same hospital in Turku, Finland were collected at monthly intervals beginning at 4-6 months after birth until 2.2 years of age. Of those 76 children, 29 seroconverted to T1D-related autoimmunity (cases including 22 who later developed T1D, the remaining 47 subjects remained healthy (controls. While several significant compositional differences in low abundant species prior to seroconversion were found, one highly abundant group composed of two closely related species, Bacteroides dorei and Bacteroides vulgatus, was significantly higher in cases compared to controls prior to seroconversion. Metagenomic sequencing of samples high in the abundance of the B. dorei/vulgatus group before seroconversion, as well as longer 16S rRNA sequencing identified this group as Bacteroides dorei. The abundance of B. dorei peaked at 7.6 months in cases, over eight months prior to the appearance of the first islet autoantibody, suggesting that early changes in the microbiome may be useful for predicting T1D autoimmunity in genetically susceptible infants. The cause of increased B. dorei abundance in cases is not known but its timing appears to coincide with the introduction of solid food.

  10. A perforated gastrovascular cavity in the symbiotic deep-water coral Leptoseris fragilis: A new strategy to optimize heterotrophic nutrition

    Science.gov (United States)

    Schlichter, Dietrich

    1991-12-01

    The organization of the zooxanthellate scleractinian coral Leptoseris fragilis was studied. The architecture of the corallite and the histology of the polyparium were analysed for adaptations that enable efficient capture and retention of suspended particles which would increase energy supply. The data indicate that the gastrovascular system of L. fragilis is not a blind but a flowthrough system. Water entering the coelenteron through the mouth leaves the body not only through the mouth but also through microscopic pores (≂ 1 2 μm) which are located near the crests of the sclerosepta in the oral epithelia. Irrigation is achieved by flagellar and probably also by muscular activity. This type of filtration enables L. fragilis, which lacks tentacles, to utilize suspended organic material including bacteria. The supposed suspension feeding in combination with effective photoadaptations (presented in former communications) seems to be the basis for the survival of L. fragilis in an extreme habitat (between-95 and-145 m) and for its, successful competion with other scleractinian species provided with larger catching surfaces, and with other invertebrates depending on filter feeding.

  11. Qualidade protéica do soro de leite fermentado pela levedura Kluyveromyces fragilis Protein quality of whey fermented by Kluyveromyces fragilis yeast

    Directory of Open Access Journals (Sweden)

    Caio Abércio da Silva

    2000-06-01

    Full Text Available O soro de leite fermentado pela levedura Kluyveromyces fragilis, após secagem em spray drier, foi submetido à avaliação da qualidade protéica através de uma análise aminoacídica e de um estudo biológico pelos métodos: Relação da Eficiência Protéica (PER, Relação da Eficiência Líquida da Proteína (NPR e Utilização Líquida da Proteína (NPU. Na análise aminoacídica, foram utilizadas como comparativo a composição de aminoácidos das proteínas padrão do ovo e da FAO. Os resultados indicaram um alto nível de lisina (65,60mg/g de proteína e baixos níveis de metionina e valina, respectivamente, 14,90mg e 45,80mg/g de proteína. A avaliação biológica foi conduzida durante 4 semanas, sendo utilizados 24 ratos desmamados aos 23 dias de idade. Os resultados para PER, NPR e NPU foram respectivamente, 19,75%, 46,33% e 26,54%, comparados com os valores obtidos com a proteína padrão caseína. A qualidade da proteína do soro seco fermentado apresentou-se inferior à proteína da caseína.Kluyveromyces fragilis fermented whey was spray dried and the protein quality of dried product was assayed by aminoacid analysis and three biological methods: Protein Efficiency Ratio (PER, Net Protein Ratio (NPR and Net Protein Utilization (NPU. Aminoacid analysis using casein and FAO protein as standards had a high level of lysine (65.6mg/g protein and low levels of methionine (14.9mg/g protein and valine (45.8mg/g protein. Biological evaluation of dried fermented whey protein, using 24 weaned rats, 23 days of age, during four weeks, using casein as standard protein, resulted in PER, NPR and NPU, 19.75%, 46.33% and 26.54%. Nutritional quality of the dried fermented whey protein was lower than the casein protein.

  12. Novel Bacteroides host strains for detection of human- and animal-specific bacteriophages in water.

    Science.gov (United States)

    Wicki, Melanie; Auckenthaler, Adrian; Felleisen, Richard; Tanner, Marcel; Baumgartner, Andreas

    2011-03-01

    Bacteriophages active against specific Bacteroides host strains were shown to be suitable for detection of human faecal pollution. However, the practical application of this finding is limited because some specific host strains were restricted to certain geographic regions. In this study, novel Bacteroides host strains were isolated that discriminate human and animal faecal pollution in Switzerland. Two strains specific for bacteriophages present in human faecal contamination and three strains specific for bacteriophages indicating animal faecal contamination were evaluated. Bacteriophages infecting human strains were exclusively found in human wastewater, whereas animal strains detected bacteriophages only in animal waste. The newly isolated host strains could be used to determine the source of surface and spring water faecal contamination in field situations. Applying the newly isolated host Bacteroides thetaiotaomicron ARABA 84 for detection of bacteriophages allowed the detection of human faecal contamination in spring water.

  13. Complete genome sequence of Bacteroides salanitronis type strain (BL78T)

    Energy Technology Data Exchange (ETDEWEB)

    Gronow, Sabine [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Held, Brittany [Los Alamos National Laboratory (LANL); Lucas, Susan [Joint Genome Institute, Walnut Creek, California; Lapidus, Alla L. [Joint Genome Institute, Walnut Creek, California; Glavina Del Rio, Tijana [Joint Genome Institute, Walnut Creek, California; Nolan, Matt [Joint Genome Institute, Walnut Creek, California; Tice, Hope [Joint Genome Institute, Walnut Creek, California; Deshpande, Shweta [Joint Genome Institute, Walnut Creek, California; Cheng, Jan-Fang [Joint Genome Institute, Walnut Creek, California; Pitluck, Sam [Joint Genome Institute, Walnut Creek, California; Liolios, Konstantinos [Joint Genome Institute, Walnut Creek, California; Pagani, Ioanna [Joint Genome Institute, Walnut Creek, California; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Pati, Amrita [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Chen, Amy [Joint Genome Institute, Walnut Creek, California; Palaniappan, Krishna [Joint Genome Institute, Walnut Creek, California; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Chang, Yun-Juan [ORNL; Jeffries, Cynthia [Oak Ridge National Laboratory (ORNL); Brambilla, Evelyne-Marie [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Rohde, Manfred [HZI - Helmholtz Centre for Infection Research, Braunschweig, Germany; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Detter, J. Chris [Joint Genome Institute, Walnut Creek, California; Woyke, Tanja [Joint Genome Institute, Walnut Creek, California; Bristow, James [Joint Genome Institute, Walnut Creek, California; Markowitz, Victor [Joint Genome Institute, Walnut Creek, California; Hugenholtz, Philip [U.S. Department of Energy, Joint Genome Institute; Kyrpides, Nikos C [Joint Genome Institute, Walnut Creek, California; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Eisen, Jonathan [Joint Genome Institute, Walnut Creek, California

    2011-01-01

    Bacteroides salanitronis Lan et al. 2006 is a species of the genus Bacteroides, which belongs to the family Bacteroidaceae. The species is of interest because it was isolated from the gut of a chicken and the growing awareness that the anaerobic microflora of the cecum is of benefit for the host and may impact poultry farming. The 4,308,663 bp long genome consists of a 4.24 Mbp chromosome and three plasmids (6 kbp, 19 kbp, 40 kbp) containing 3,737 protein-coding and 101 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  14. The gut bacterial communities associated with lab-raised and field-collected ants of Camponotus fragilis (Formicidae: Formicinae).

    Science.gov (United States)

    He, Hong; Wei, Cong; Wheeler, Diana E

    2014-09-01

    Camponotus is the second largest ant genus and known to harbor the primary endosymbiotic bacteria of the genus Blochmannia. However, little is known about the effect of diet and environment changes on the gut bacterial communities of these ants. We investigated the intestinal bacterial communities in the lab-raised and field-collected ants of Camponotus fragilis which is found in the southwestern United States and northern reaches of Mexico. We determined the difference of gut bacterial composition and distribution among the crop, midgut, and hindgut of the two types of colonies. Number of bacterial species varied with the methods of detection and the source of the ants. Lab-raised ants yielded 12 and 11 species using classical microbial culture methods and small-subunit rRNA genes (16S rRNAs) polymerase chain reaction-restriction fragment-length polymorphism analysis, respectively. Field-collected ants yielded just 4 and 1-3 species using the same methods. Most gut bacterial species from the lab-raised ants were unevenly distributed among the crop, midgut, and hindgut, and each section had its own dominant bacterial species. Acetobacter was the prominent bacteria group in crop, accounting for about 55 % of the crop clone library. Blochmannia was the dominant species in midgut, nearly reaching 90 % of the midgut clone library. Pseudomonas aeruginosa dominated the hindgut, accounting for over 98 % of the hindgut clone library. P. aeruginosa was the only species common to all three sections. A comparison between lab-raised and field-collected ants, and comparison with other species, shows that gut bacterial communities vary with local environment and diet. The bacterial species identified here were most likely commensals with little effect on their hosts or mild pathogens deleterious to colony health.

  15. Current Status of Marker Genes of Bacteroides and Related Taxa for Identifying Sewage Pollution in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Warish Ahmed

    2016-05-01

    Full Text Available Microbial source tracking (MST endeavors to determine sources of fecal pollution in environmental waters by capitalizing on the association of certain microorganisms with the gastrointestinal tract and feces of specific animal groups. Several decades of research have shown that bacteria belonging to the gut-associated order Bacteroidales, and particularly the genus Bacteroides, tend to co-evolve with the host, and are, therefore, particularly suitable candidates for MST applications. This review summarizes the current research on MST methods that employ genes belonging to Bacteroidales/Bacteroides as tracers or “markers” of sewage pollution, including known advantages and deficiencies of the many polymerase chain reaction (PCR-based methods that have been published since 2000. Host specificity is a paramount criterion for confidence that detection of a marker is a true indicator of the target host. Host sensitivity, or the prevalence of the marker in feces/waste from the target host, is necessary for confidence that absence of the marker is indicative of the absence of the pollution source. Each of these parameters can vary widely depending on the type of waste assessed and the geographic location. Differential decay characteristics of bacterial targets and their associated DNA contribute to challenges in interpreting MST results in the context of human health risks. The HF183 marker, derived from the 16S rRNA gene of Bacteroides dorei and closely related taxa, has been used for almost two decades in MST studies, and is well characterized regarding host sensitivity and specificity, and in prevalence and concentration in sewage in many countries. Other markers such as HumM2 and HumM3 show promise, but require further performance testing to demonstrate their widespread utility. An important limitation of the one-marker-one-assay approach commonly used for MST is that given the complexities of microbial persistence in environmental waters, and

  16. Effects of Ephedrine and Ephedra fragilis Crude Extracts on Human Peripheral Lymphocytes

    Directory of Open Access Journals (Sweden)

    E Attard

    2009-01-01

    Full Text Available Ephedra fragilis Desf. (Ephedraceae, a locally cultivated medicinal plant, is a source of ephedrine and pseudoephedrine, two important alkaloids, which have long played an important pharmacological role. The present study investigated the in vitro effects of ephedrine and the Ephedra branch extract on unstimulated lymphocytes. Ephedra alkaloids were extracted from various plant parts and after phytochemical analysis, the brine shrimp lethality test was used to determine the activity of the extracts. The LC 50 of the branch extract was 581.395 μg/ml, showing no statistical difference from that of ephedrine (208.203 μg/ml. The ephedrine and extract did not show toxic effects on lymphocytes but exhibited immunostimulant activity. Although ephedrine cannot be used as an immune booster, it can be used as a lead drug for further immunological research.

  17. Fragilisinins A–L, new briarane-type diterpenoids from gorgonian Junceella fragilis

    KAUST Repository

    Lei, Hui

    2014-01-01

    Our continuous study on the South China Sea gorgonian Junceella fragilis led to the isolation of twelve new briarane type diterpenoids, fragilisinins A-L (1-12), along with seven known analogues (13-19), including four naturally produced organoiodides (9-12), they are the first four iodine-containing briarane diterpenoids from this gorgonian species. Their structures were determined by MS, 1D and 2D NMR spectra analyses and by comparison with those reported in the literature. The configuration of 1 was confirmed by single-crystal X-ray diffraction data. The antifouling test showed that compounds 5, 6, 10, 13, and 15 had potent antifouling activities at nontoxic concentrations with EC50 values of 14.0, 12.6, 11.9, 5.6, and 10.0 μM, respectively. © 2014 The Royal Society of Chemistry.

  18. Growth inhibitory effects of endotoxins from Bacteroides gingivalis and intermedius on human gingival fibroblasts in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Layman, D.L.; Diedrich, D.L.

    1987-06-01

    Purified endotoxin or lipopolysaccharide from Bacteroides gingivalis and Bacteroides intermedius caused a similar dose-dependent inhibition of growth of cultured human gingival fibroblasts as determined by /sup 3/H-thymidine incorporation and direct cell count. Approximately 200 micrograms/ml endotoxin caused a 50% reduction in /sup 3/H-thymidine uptake of logarithmically growing cells. Inhibition of growth was similar in cultures of fibroblasts derived from either healthy or diseased human gingiva. When examining the change in cell number with time of exposure in culture, the rate of proliferation was significantly suppressed during the logarithmic phase of growth. However, the cells recovered so that the rate of proliferation, although reduced, was sufficient to produce a cell density similar to the control cells with prolonged culture. The endotoxins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The profiles of the Bacteroides endotoxins were different. B. gingivalis endotoxin showed a wide range of distinct bands indicating a heterogeneous distribution of molecular species. Endotoxin from B. intermedius exhibited a few discrete low molecular weight bands, but the majority of the lipopolysaccharides electrophoresed as a diffuse band of high molecular weight material. The apparent heterogeneity of the two Bacteroides endotoxins and the similarity in growth inhibitory capacity suggest that growth inhibitory effects of these substances cannot be attributed to any polysaccharide species of endotoxin.

  19. Extensive Mobilome-Driven Genome Diversification in Mouse Gut-Associated Bacteroides vulgatus mpk.

    Science.gov (United States)

    Lange, Anna; Beier, Sina; Steimle, Alex; Autenrieth, Ingo B; Huson, Daniel H; Frick, Julia-Stefanie

    2016-01-01

    Like many other Bacteroides species, Bacteroides vulgatus strain mpk, a mouse fecal isolate which was shown to promote intestinal homeostasis, utilizes a variety of mobile elements for genome evolution. Based on sequences collected by Pacific Biosciences SMRT sequencing technology, we discuss the challenges of assembling and studying a bacterial genome of high plasticity. Additionally, we conducted comparative genomics comparing this commensal strain with the B. vulgatus type strain ATCC 8482 as well as multiple other Bacteroides and Parabacteroides strains to reveal the most important differences and identify the unique features of B. vulgatus mpk. The genome of B. vulgatus mpk harbors a large and diverse set of mobile element proteins compared with other sequenced Bacteroides strains. We found evidence of a number of different horizontal gene transfer events and a genome landscape that has been extensively altered by different mobilization events. A CRISPR/Cas system could be identified that provides a possible mechanism for preventing the integration of invading external DNA. We propose that the high genome plasticity and the introduced genome instabilities of B. vulgatus mpk arising from the various mobilization events might play an important role not only in its adaptation to the challenging intestinal environment in general, but also in its ability to interact with the gut microbiota.

  20. Neuraminidase-enhanced attachment of Bacteroides intermedius to human erythrocytes and buccal epithelial cells.

    OpenAIRE

    Okuda, K; Ono, M.; Kato, T.

    1989-01-01

    Bacteroides intermedius strains strongly agglutinated only neuraminidase-treated erythrocytes. The neuraminidase-dependent hemagglutinating activity of B. intermedius was abolished by heating or treating with protease. The adherence of these microorganisms to human buccal epithelial cells was enhanced by neuraminidase pretreatment of the cells (P less than 0.01).

  1. Energy supply for dinitrogen fixation by Azotobacter vinelandii and by bacteroids of Rhizobium leguminosarum

    NARCIS (Netherlands)

    Laane, N.C.M.

    1980-01-01

    The central issue of this thesis is how obligate aerobes, such as Rhizobium leguminosarum bacteroids and Azotobacter vinelandii, generate and regulate the energy supply (in the form of ATP and reducing equivalents) for nitrogenase.In an effective Rhizobium -legume symbiosis, the actual reduction of

  2. Silting up and development of anoxic conditions enhanced by high abundance of the geoengineer species Ophiothrix fragilis

    Science.gov (United States)

    Murat, A.; Méar, Y.; Poizot, E.; Dauvin, J. C.; Beryouni, K.

    2016-04-01

    In the English Channel, the brittle-star Ophiothrix fragilis is a common epifaunal species typically found on pebbles in habitats with strong tidal currents. This species forms dense aggregations on the seafloor, supporting populations that can reach up to 7500 ind m-2 in the eastern part of the Baie de Seine, offshore from Antifer harbour. Here, O. fragilis occurs in an area with unexpected amounts of fine-grained sediment. Some of these mud deposits are made up of unusually compact black muds, an indication of the development of anoxic conditions in surficial sediments. To highlight a potential link between silting up and dense O. fragilis populations, and identify the interactions between environmental conditions and the population dynamics of this species, we analyse the data from three surveys corresponding to exceptional situations: (1) just after a Seine flood; (2) just after a storm and (3) after a period of ten months without any flood or storm. Four parameters are taken into account: number of brittle stars per 0.25 m2, Fine Fraction percentage, Total Organic Carbon and Total Sulphur. The main environmental forcings appear to be Seine river inflow, regional circulation dependent on tidal currents and the occurrence of storms. O. fragilis is able to geoengineer its environment in various ways and at different rates. Silting up is enhanced by increasing abundance of O. fragilis and takes place at a very fast rate. As a result, floods and storms reflecting instantaneous events give rise to a steady-state situation established between the abundance of this species and the fine fraction percentage. Anoxic conditions are dependent on the degradation of organic matter and require more time to be established. After many months in the absence of any disturbing events, anoxic conditions are developed in non-compacted muddy sediments (stability situation) and represent the normal surficial situation when the sediment becomes compacted (compact black muds). The

  3. Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

    Energy Technology Data Exchange (ETDEWEB)

    Patters, M.R.; Landsberg, R.L.; Johansson, L.A.; Trummel, C.L.; Robertson, P.R. (Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington, Connecticut, U.S.A.)

    1982-01-01

    Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated /sup 45/Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.

  4. Activity of benzimidazoles against Dientamoeba fragilis (Trichomonadida, Monocercomonadidae in vitro and correlation of beta-tubulin sequences as an indicator of resistance

    Directory of Open Access Journals (Sweden)

    Stark Damien

    2014-01-01

    Full Text Available Recently, Dientamoeba fragilis has emerged as a significant and common enteropathogen. The majority of patients with dientamoebiasis present with gastrointestinal complaints and chronic symptoms are common. Numerous studies have successfully demonstrated parasite clearance, coupled with complete resolution of clinical symptoms following treatment with various antiparasitic compounds. Despite this, there is very little in vitro susceptibility data available for the organism. Benzimidazoles are a class of antiparasitic drugs that are commonly used for the treatment of protozoan and helminthic infections. Susceptibility testing was undertaken on four D. fragilis clinical isolates against the following benzimidazoles: albendazole, flubendazole, mebendazole, nocodazole, triclabendazole and thiabendazole. The activities of the antiprotozoal compounds at concentrations ranging from 2 μg/mL to 500 μg/mL were determined via cell counts of D. fragilis grown in xenic culture. All tested drugs showed no efficacy. The beta-tubulin transcript was sequenced from two of the D. fragilis isolates and amino acid sequences predicted a susceptibility to benzimidazoles. This is the first study to report susceptibility profiles for benzimidazoles against D. fragilis, all of which were not active against the organism. This study also found that beta-tubulin sequences cannot be used as a reliable marker for resistance of benzimidazoles in D. fragilis.

  5. Pyruvate is synthesized by two pathways in pea bacteroids with different efficiencies for nitrogen fixation.

    Science.gov (United States)

    Mulley, Geraldine; Lopez-Gomez, Miguel; Zhang, Ye; Terpolilli, Jason; Prell, Jurgen; Finan, Turlough; Poole, Philip

    2010-10-01

    Nitrogen fixation in legume bacteroids is energized by the metabolism of dicarboxylic acids, which requires their oxidation to both oxaloacetate and pyruvate. In alfalfa bacteroids, production of pyruvate requires NAD+ malic enzyme (Dme) but not NADP+ malic enzyme (Tme). However, we show that Rhizobium leguminosarum has two pathways for pyruvate formation from dicarboxylates catalyzed by Dme and by the combined activities of phosphoenolpyruvate (PEP) carboxykinase (PckA) and pyruvate kinase (PykA). Both pathways enable N2 fixation, but the PckA/PykA pathway supports N2 fixation at only 60% of that for Dme. Double mutants of dme and pckA/pykA did not fix N2. Furthermore, dme pykA double mutants did not grow on dicarboxylates, showing that they are the only pathways for the production of pyruvate from dicarboxylates normally expressed. PckA is not expressed in alfalfa bacteroids, resulting in an obligate requirement for Dme for pyruvate formation and N2 fixation. When PckA was expressed from a constitutive nptII promoter in alfalfa dme bacteroids, acetylene was reduced at 30% of the wild-type rate, although this level was insufficient to prevent nitrogen starvation. Dme has N-terminal, malic enzyme (Me), and C-terminal phosphotransacetylase (Pta) domains. Deleting the Pta domain increased the peak acetylene reduction rate in 4-week-old pea plants to 140 to 150% of the wild-type rate, and this was accompanied by increased nodule mass. Plants infected with Pta deletion mutants did not have increased dry weight, demonstrating that there is not a sustained change in nitrogen fixation throughout growth. This indicates a complex relationship between pyruvate synthesis in bacteroids, nitrogen fixation, and plant growth.

  6. Detection of Dientamoeba fragilis in patients with HIV/AIDS by using a simplified iron hematoxylin technique

    Directory of Open Access Journals (Sweden)

    Juliana Alves Garcia

    2012-04-01

    Full Text Available INTRODUCTION: Studies strongly indicate Dientamoeba fragilis as one of the causes of diarrhea in human immunodeficiency virus (HIV patients. METHODS: The objective of the present study was to evaluate the prevalence of D. fragilis associated with the causes of diarrhea in 82 HIV/ AIDS patients hospitalized at the Instituto de Infectologia Emílio Ribas from September 2006 to November 2008. RESULTS: In total, 105 samples were collected from 82 patients. Unprotected sex was the most frequent cause of HIV infection (46.3%, followed by the use of injectable or non-injectable drugs (14.6%. Patients presented with viral loads of 49-750,000 copies/ mL (average: 73,849 ± 124,850 copies/mL and CD4 counts ranging of 2-1,306 cells/mm³ (average: 159 ± 250 cells/mm³. On an average, the odds of obtaining a positive result by using the other techniques (Hoffman, Pons and Janer or Lutz; Ritchie were 2.7 times higher than the chance of obtaining a positive result by using the simplified iron hematoxylin method. Significant differences were found between the methods (p = 0.003. CONCLUSIONS: The other techniques can detect a significantly greater amount of parasites than the simplified iron hematoxylin method, especially with respect to Isospora belli, Cryptosporidium sp., Schistosoma mansoni, and Strongyloides stercoralis, which were not detected using hematoxylin. Endolimax nana and D. fragilis were detected more frequently on using hematoxylin, and the only parasite not found by the other methods was D. fragilis.

  7. Analysis of proteins associated with growth of Bacteroides ovatus on the branched galactomannan guar gum.

    OpenAIRE

    Valentine, P J; Salyers, A A

    1992-01-01

    Bacteroides ovatus, a gram-negative obligate anaerobe from the human colon, can ferment the branched galactomannan guar gum. Previously, three enzymes involved in guar gum breakdown were characterized. The expression of these enzymes appeared to be regulated; i.e., specific activities were higher in extracts from bacteria grown on guar gum than in extracts from bacteria grown on the monosaccharide constituents of guar gum, mannose and galactose. In the present study, we used two-dimensional g...

  8. Two Sinorhizobium meliloti glutaredoxins regulate iron metabolism and symbiotic bacteroid differentiation.

    Science.gov (United States)

    Benyamina, Sofiane M; Baldacci-Cresp, Fabien; Couturier, Jérémy; Chibani, Kamel; Hopkins, Julie; Bekki, Abdelkader; de Lajudie, Philippe; Rouhier, Nicolas; Jacquot, Jean-Pierre; Alloing, Geneviève; Puppo, Alain; Frendo, Pierre

    2013-03-01

    Legumes interact symbiotically with bacteria of the Rhizobiaceae to form nitrogen-fixing root nodules. We investigated the contribution of the three glutaredoxin (Grx)-encoding genes present in the Sinorhizobium meliloti genome to this symbiosis. SmGRX1 (CGYC active site) and SmGRX3 (CPYG) recombinant proteins displayed deglutathionylation activity in the 2-hydroethyldisulfide assay, whereas SmGRX2 (CGFS) did not. Mutation of SmGRX3 did not affect S. meliloti growth or symbiotic capacities. In contrast, SmGRX1 and SmGRX2 mutations decreased the growth of free-living bacteria and the nitrogen fixation capacity of bacteroids. Mutation of SmGRX1 led to nodule abortion and an absence of bacteroid differentiation, whereas SmGRX2 mutation decreased nodule development without modifying bacteroid development. The higher sensitivity of the Smgrx1 mutant strain as compared with wild-type strain to oxidative stress was associated with larger amounts of glutathionylated proteins. The Smgrx2 mutant strain displayed significantly lower levels of activity than the wild type for two iron-sulfur-containing enzymes, aconitase and succinate dehydrogenase. This lower level of activity could be associated with deregulation of the transcriptional activity of the RirA iron regulator and higher intracellular iron content. Thus, two S. meliloti Grx proteins are essential for symbiotic nitrogen fixation, playing independent roles in bacterial differentiation and the regulation of iron metabolism.

  9. In vivo efficacy of trovafloxacin against Bacteroides fragilis in mixed infection with either Escherichia coli or a vancomycin-resistant strain of Enterococcus faecium in an established-abscess murine model.

    NARCIS (Netherlands)

    L.E.T. Stearne (Lorna); I.C. Gyssens (Inge); W.H.F. Goessens (Wil); J.W. Mouton (Johan); W.J. Oyen (Wim); J.W. van der Meer; H.A. Verbrugh (Henri)

    2001-01-01

    textabstractThe pharmacodynamic and pharmacokinetic properties of trovafloxacin were studied in a standardized murine model of established subcutaneous abscesses. Daily dosing regimens of 37.5 to 300 mg/kg every 8 h (q8h) or every 24 h (q24h) were started 3 days after i

  10. Inactivation of murine norovirus 1, coliphage phiX174, and Bacteroides [corrected] fragilis phage B40-8 on surfaces and fresh-cut iceberg lettuce by hydrogen peroxide and UV light.

    Science.gov (United States)

    Li, Dan; Baert, Leen; De Jonghe, Maarten; Van Coillie, Els; Ryckeboer, Jaak; Devlieghere, Frank; Uyttendaele, Mieke

    2011-02-01

    In this study, the inactivating properties of liquid hydrogen peroxide (L-H(2)O(2)), vaporized hydrogen peroxide (V-H(2)O(2)), UV light, and a combination of V-H(2)O(2) and UV light were tested on murine norovirus 1 (MNV-1) and bacteriophages (φX174 and B40-8) as models for human noroviruses. Disinfection of surfaces was examined on stainless steel discs based on European Standard EN 13697 (2001). For fresh-produce decontamination, a mixture of the viruses was inoculated onto shredded iceberg lettuce and treated after overnight incubation at 2°C. According to our results, L-H(2)O(2) (2.1%) was able to inactivate MNV-1 and φX174 on stainless steel discs by approximately 4 log(10) units within 10 min of exposure, whereas for B40-8, 15% of L-H(2)O(2) was needed to obtain a similar reduction in 10 min. Only a marginal reduction (≤1 log(10) unit after 5 min of exposure) by V-H(2)O(2) (2.52%) was achieved for the tested model viruses, although in combination with UV light, a 4-log(10)-unit decrease within 5 min of treatment was observed on stainless steel discs. Similar trends were observed for the decontamination of shredded iceberg lettuce, but the viral decline was reduced. These results demonstrated that both L-H(2)O(2) and a combination of V-H(2)O(2) and UV light can be used for norovirus inactivation on surfaces; V-H(2)O(2) (2.52%) in combination with UV light is promising for decontamination of fresh produce with much less consumption of water and disinfectant.

  11. Inactivation of murine Norovirus-1, coliphage φX174 and Bacteroides fragilis phage B40-8 on surfaces and fresh cut iceberg lettuce by hydrogen peroxide and UV light

    OpenAIRE

    2011-01-01

    In this study, the inactivating properties of liquid hydrogen peroxide (L-H2O2), vaporized hydrogen peroxide (V-H2O2), UV light, and a combination of V-H2O2 and UV light were tested on murine norovirus 1 (MNV-1) and bacteriophages (φX174 and B40-8) as models for human noroviruses. Disinfection of surfaces was examined on stainless steel discs based on European Standard EN 13697 (2001). For fresh-produce decontamination, a mixture of the viruses was inoculated onto shredded iceberg lettuce and...

  12. An electron microscope survey of the surface structures and hydrophobicity of oral and non-oral species of the bacterial genus Bacteroides.

    Science.gov (United States)

    Handley, P S; Tipler, L S

    1986-01-01

    Seventeen strains of Bacteroides representing 10 species were examined by negative staining; the majority were from the mouth but a few non-oral strains were included. Seven species had peritrichously-arranged, non-flagellar appendages which could be divided by morphology and ultrastructure into two subgroups, fibrils and fimbriae. Bacteroides asaccharolyticus strains B536 and B537 and Bacteroides gingivalis strains W50, W83, WPH15 and WPH35 had fimbriae with mean width of 4.4 nm and 0.5 to 6.0 microns long depending on the strain. The fimbrial length within each strain also varied. Fibrils were present on two fresh oral isolates of Bacteroides melaninogenicus, Bacteroides intermedius strains T588 and W09, Bacteroides corporis ATCC 33547, Bacteroides oralis ATCC 33269 and Bacteroides buccae ATCC 33574. Fibrils consistently clumped into bundles of variable thickness and formed a fringe around the cell periphery, ranging from 0.27 to 1.2 microns long depending on the strain. Fibril lengths of each strain were uniform. Fibrils had no measurable width and the clumps tapered towards the free ends. Bacteroides loeschii VPI 9085, Bacteroides pentosaceus strains NP333 and J1 and Bacteroides capillosus 29799 had no detectable surface appendages. Fimbriate strains had a layer outside the outer membrane, with a mean thickness of between 17.8 and 28.6 nm. Both fibrillar and fimbriate strains produced many small membranous vesicles budding from the outer membrane. There were two morphological forms of vesicles, ones with either fimbriae or fibrils (species-dependent) and ones with no attached appendages. Of eleven strains tested for cell-surface hydrophobicity by partitioning between hexadecane and buffer, all but one was non-hydrophobic.

  13. Impact of probiotics on colonic microflora in patients with colitis

    DEFF Research Database (Denmark)

    Reddy, B. S.; Ahmed, J.; Macfie, J.;

    2010-01-01

    years (IQR 50–65). An average of 22 T-RF’s was identified in each patient. Dice cluster analysis showed that each patient had a unique microbial spectrum and did not change significantly at different points in the study in both groups. T-RF 102bp potential representing Bacteroides fragilis was the only...

  14. High quality draft genome sequence of Bacteroides barnesiae type strain BL2(T) (DSM 18169(T)) from chicken caecum.

    Science.gov (United States)

    Sakamoto, Mitsuo; Lapidus, Alla L; Han, James; Trong, Stephan; Haynes, Matthew; Reddy, T B K; Mikhailova, Natalia; Huntemann, Marcel; Pati, Amrita; Ivanova, Natalia N; Pukall, Rüdiger; Markowitz, Victor M; Woyke, Tanja; Klenk, Hans-Peter; Kyrpides, Nikos C; Ohkuma, Moriya

    2015-01-01

    Bacteroides barnesiae Lan et al. 2006 is a species of the genus Bacteroides, which belongs to the family Bacteroidaceae. Strain BL2(T) is of interest because it was isolated from the gut of a chicken and the growing awareness that the anaerobic microbiota of the caecum is of benefit for the host and may impact poultry farming. The 3,621,509 bp long genome with its 3,059 protein-coding and 97 RNA genes is a part of the Genomic Encyclopedia of Type Strains, Phase I: the one thousand microbial genomes (KMG) project.

  15. Medicago truncatula root nodule proteome analysis reveals differential plant and bacteroid responses to drought stress.

    Science.gov (United States)

    Larrainzar, Estíbaliz; Wienkoop, Stefanie; Weckwerth, Wolfram; Ladrera, Rubén; Arrese-Igor, Cesar; González, Esther M

    2007-07-01

    Drought is one of the environmental factors most affecting crop production. Under drought, symbiotic nitrogen fixation is one of the physiological processes to first show stress responses in nodulated legumes. This inhibition process involves a number of factors whose interactions are not yet understood. This work aims to further understand changes occurring in nodules under drought stress from a proteomic perspective. Drought was imposed on Medicago truncatula 'Jemalong A17' plants grown in symbiosis with Sinorhizobium meliloti strain 2011. Changes at the protein level were analyzed using a nongel approach based on liquid chromatography coupled to tandem mass spectrometry. Due to the complexity of nodule tissue, the separation of plant and bacteroid fractions in M. truncatula root nodules was first checked with the aim of minimizing cross contamination between the fractions. Second, the protein plant fraction of M. truncatula nodules was profiled, leading to the identification of 377 plant proteins, the largest description of the plant nodule proteome so far. Third, both symbiotic partners were independently analyzed for quantitative differences at the protein level during drought stress. Multivariate data mining allowed for the classification of proteins sets that were involved in drought stress responses. The isolation of the nodule plant and bacteroid protein fractions enabled the independent analysis of the response of both counterparts, gaining further understanding of how each symbiotic member is distinctly affected at the protein level under a water-deficit situation.

  16. Modulation of endogenous indole-3-acetic acid biosynthesis in bacteroids within Medicago sativa nodules.

    Science.gov (United States)

    Bianco, C; Senatore, B; Arbucci, S; Pieraccini, G; Defez, R

    2014-07-01

    To evaluate the dose-response effects of endogenous indole-3-acetic acid (IAA) on Medicago plant growth and dry weight production, we increased the synthesis of IAA in both free-living and symbiosis-stage rhizobial bacteroids during Rhizobium-legume symbiosis. For this purpose, site-directed mutagenesis was applied to modify an 85-bp promoter sequence, driving the expression of iaaM and tms2 genes for IAA biosynthesis. A positive correlation was found between the higher expression of IAA biosynthetic genes in free-living bacteria and the increased production of IAA under both free-living and symbiotic conditions. Plants nodulated by RD65 and RD66 strains, synthetizing the highest IAA concentration, showed a significant (up to 73%) increase in the shoot fresh weight and upregulation of nitrogenase gene, nifH, compared to plants nodulated by the wild-type strain. When these plants were analyzed by confocal microscopy, using an anti-IAA antibody, the strongest signal was observed in bacteroids of Medicago sativa RD66 (Ms-RD66) plants, even when they were located in the senescent nodule zone. We show here a simple system to modulate endogenous IAA biosynthesis in bacteria nodulating legumes suitable to investigate which is the maximum level of IAA biosynthesis, resulting in the maximal increase of plant growth.

  17. The methylome of the gut microbiome: disparate Dam methylation patterns in intestinal Bacteroides dorei

    Directory of Open Access Journals (Sweden)

    Michael T. Leonard

    2014-07-01

    Full Text Available Despite the large interest in the human microbiome in recent years, there are no reports of bacterial DNA methylation in the microbiome. Here metagenomic sequencing using the Pacific Biosciences platform allowed for rapid identification of bacterial GATC methylation status of a bacterial species in human stool samples. For this work, two stool samples were chosen that were dominated by a single species, Bacteroides dorei. Based on 16S rRNA analysis, this species represented over 45% of the bacteria present in these two samples. The B. dorei genome sequence from these samples was determined and the GATC methylation sites mapped. The Bacteroides dorei genome from one subject lacked any GATC methylation and lacked the DNA adenine methyltransferase genes. In contrast, B. dorei from another subject contained 20,551 methylated GATC sites. Of the 4,970 open reading frames identified in the GATC methylated B. dorei genome, 3,184 genes were methylated as well as 1,735 GATC methylations in intergenic regions. These results suggest that DNA methylation patterns are important to consider in multi-omic analyses of microbiome samples seeking to discover the diversity of bacterial functions and may differ between disease states.

  18. Terminal Bacteroid Differentiation Is Associated With Variable Morphological Changes in Legume Species Belonging to the Inverted Repeat-Lacking Clade.

    Science.gov (United States)

    Montiel, Jesús; Szűcs, Attila; Boboescu, Iulian Z; Gherman, Vasile D; Kondorosi, Éva; Kereszt, Attila

    2016-03-01

    Medicago and closely related legume species from the inverted repeat-lacking clade (IRLC) impose terminal differentiation onto their bacterial endosymbionts, manifested in genome endoreduplication, cell enlargement, and loss of cell-division capacity. Nodule-specific cysteine-rich (NCR) secreted host peptides are plant effectors of this process. As bacteroids in other IRLC legumes, such as Cicer arietinum and Glycyrrhiza lepidota, were reported not to display features of terminal differentiation, we investigated the fate of bacteroids in species from these genera as well as in four other species representing distinct genera of the phylogenetic tree for this clade. Bacteroids in all tested legumes proved to be larger in size and DNA content than cultured cells; however, the degree of cell elongation was rather variable in the different species. In addition, the reproductive ability of the bacteroids isolated from these legumes was remarkably reduced. In all IRLC species with available sequence data, the existence of NCR genes was found. These results indicate that IRLC legumes provoke terminal differentiation of their endosymbionts with different morphotypes, probably with the help of NCR peptides.

  19. Levan Enhances Associated Growth of Bacteroides, Escherichia, Streptococcus and Faecalibacterium in Fecal Microbiota

    DEFF Research Database (Denmark)

    Adamberg, Kaarel; Tomson, Katrin; Talve, Tiina

    2015-01-01

    were determined. The composition of fecal microbiota and profile of metabolites changed in response to substrate (levan and amino acids) availability. The main products of levan metabolism were acetic, lactic, butyric, propionic and succinic acids and carbon dioxide. Associated growth of levan....... Eleven fecal samples from healthy donors were incubated in phosphate-buffered defined medium with or without levan supplementation and varying presence of amino acids. The generation of heat, changes in pH and microbiota composition, concentrations of produced and consumed metabolites during the growth......-degrading (e.g. Bacteroides) and butyric acid-producing (e.g. Faecalibacterium) taxa was observed in levan-supplemented media. The study shows that the capacity of levan and possibly also other dietary fibers/prebiotics to modulate the composition and function of colon microbiota can be predicted by using...

  20. Prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica/dispar, and Cryptosporidium spp in Da Nang, Vietnam, detected by a multiplex real-time PCR.

    Science.gov (United States)

    Ögren, Jessica; Van Nguyen, Song; Nguyen, Minh Khac; Dimberg, Jan; Matussek, Andreas

    2016-06-01

    We surveyed the prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica, Entamoeba dispar, and Cryptosporidium spp in individuals with and without gastrointestinal (GI) symptoms residing in and around Da Nang city, Vietnam. Fecal samples were collected from children (n = 100) and adults (n = 80) with GI symptoms and from healthy individuals (n = 88) reporting no GI symptoms. Parasite detection was performed by multiplex real-time PCR. Overall, except for G. duodenalis, we found a low prevalence (histolytica and C. spp in all participants with GI symptoms. Specifically for D. fragilis this contrasts with findings in European populations of children with GI symptoms showing prevalence up to 73%. Moreover, our results indicate that the prevalence of G. duodenalis is higher in patients with GI symptoms compared to asymptomatic individuals and this difference is most obvious in young patients.

  1. Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels

    Science.gov (United States)

    Nichols, S. Jerrine; Amberg, Jon

    1999-01-01

    In 1996, thousands of live Leptodea fragilis were collected from a marsh located in the western basin of Lake Erie that was infested with zebra mussels (Dreissena polymorpha). Despite the presence of zebra mussels at this site for a number of years, this L. fragilis population showed no signs of competition-induced changes in population dynamics. Biofouling was limited: fewer than 1% of the L. fragilis showed evidence of recent or past zebra mussel colonization. Successful recruitment occurred yearly, with multiple year classes collected that ranged in age from 1 to 12 years. However, age and shell length were not well correlated. Seventy-one percent of the individuals collected were 51-80 mm long, but ranged in age from 2 to 4.5 years. Three different patterns of growth or shell deposition were found. Some individuals grew rapidly, reaching 105 mm in 3.5 years, while others grew only 4.5 mm over the same time period. A few grew poorly during some years but very rapidly in others. Individuals with a shell length of 41 mm or more were sexually mature and females were more common than males. The strong recruitment and steady growth of this population showed no change between the years before and after the zebra mussel invasion, indicating that this marsh is functioning as a natural refugium from potential problems caused by zebra mussels.

  2. A Closer Look at Bacteroides: Phylogenetic Relationship and Genomic Implications of a Life in the Human Gut

    DEFF Research Database (Denmark)

    Karlsson, Fredrik H.; Ussery, David; Nielsen, Jens;

    2011-01-01

    The human gut is extremely densely inhabited by bacteria mainly from two phyla, Bacteroidetes and Firmicutes, and there is a great interest in analyzing whole-genome sequences for these species because of their relation to human health and disease. Here, we do whole-genome comparison of 105 Bacte...... of members of the Bacteroidetes/Chlorobi phylum by whole genome comparison. Gut living Bacteroides have an enriched set of glycan, vitamin, and cofactor enzymes important for diet digestion.......The human gut is extremely densely inhabited by bacteria mainly from two phyla, Bacteroidetes and Firmicutes, and there is a great interest in analyzing whole-genome sequences for these species because of their relation to human health and disease. Here, we do whole-genome comparison of 105...... Bacteroidetes/Chlorobi genomes to elucidate their phylogenetic relationship and to gain insight into what is separating the gut living Bacteroides and Parabacteroides genera from other Bacteroidetes/Chlorobi species. A comprehensive analysis shows that Bacteroides species have a higher number...

  3. Decrease in anaerobe-related bacteraemias and increase in Bacteroides species isolation rate from 1998 to 2007: a retrospective study.

    Science.gov (United States)

    Lazarovitch, Tsilia; Freimann, Sarit; Shapira, Galina; Blank, Helena

    2010-06-01

    Conflicting data have accumulated in recent years regarding the incidence of anaerobic bacteraemias. The aim of this study was to determine the prevalence of bacteraemias due to anaerobic bacteria and evaluate the importance of anaerobic blood cultures in a university hospital in Israel. A retrospective survey which focused on anaerobic blood culture bottles was performed on blood cultures received in our laboratory during the decade from January 1998 to December 2007. Anaerobic-related bacteraemias decreased during that period, whereas a significant increase was observed in Bacteroides species isolated from the blood cultures (from 18% during 1998-2002 to 43% during 2003-2007). Comparison of the medical records of 54 patients with Bacteroides-related bacteraemia during the two end periods (1998-1999 and 2006-2007) revealed a marked increase in complex underlying diseases. Hypertension and diabetes mellitus type II were found in 29% of the patients in 1998-1999 and increased to 43-45% of the patients in 2006-2007. Ischemic heart disease also increased from 14% of the patients in 1998-1999 to 43% in 2006-2007. We conclude that although positive anaerobic blood cultures account for a small percentage of positive blood samples, the growing involvement of Bacteroides species-related bacteraemias together with an increase in complex underlying diseases in these patients emphasize the importance of anaerobic blood cultures, particularly in patients with co-morbidities.

  4. Two New Xylanases with Different Substrate Specificities from the Human Gut Bacterium Bacteroides intestinalis DSM 17393

    KAUST Repository

    Hong, Pei-Ying

    2014-01-24

    Xylan is an abundant plant cell wall polysaccharide and is a dominant component of dietary fiber. Bacteria in the distal human gastrointestinal tract produce xylanase enzymes to initiate the degradation of this complex heteropolymer. These xylanases typically derive from glycoside hydrolase (GH) families 10 and 11; however, analysis of the genome sequence of the xylan-degrading human gut bacterium Bacteroides intestinalis DSM 17393 revealed the presence of two putative GH8 xylanases. In the current study, we demonstrate that the two genes encode enzymes that differ in activity. The xyn8A gene encodes an endoxylanase (Xyn8A), and rex8A encodes a reducing-end xylose-releasing exo-oligoxylanase (Rex8A). Xyn8A hydrolyzed both xylopentaose (X5) and xylohexaose (X6) to a mixture of xylobiose (X2) and xylotriose (X3), while Rex8A hydrolyzed X3 through X6 to a mixture of xylose (X1) and X2. Moreover, rex8A is located downstream of a GH3 gene (xyl3A) that was demonstrated to exhibit β-xylosidase activity and would be able to further hydrolyze X2 to X1. Mutational analyses of putative active site residues of both Xyn8A and Rex8A confirm their importance in catalysis by these enzymes. Recent genome sequences of gut bacteria reveal an increase in GH8 Rex enzymes, especially among the Bacteroidetes, indicating that these genes contribute to xylan utilization in the human gut.

  5. Prebiotic galactooligosaccharides activate mucin and pectic galactan utilization pathways in the human gut symbiont Bacteroides thetaiotaomicron

    Science.gov (United States)

    Lammerts van Bueren, Alicia; Mulder, Marieke; Leeuwen, Sander van; Dijkhuizen, Lubbert

    2017-01-01

    Galactooligosaccharides (GOS) are prebiotic carbohydrates that impart changes in the gut bacterial composition of formula-fed infants to more closely resemble that of breast-fed infants. Consuming human milk oligosaccharides (HMOs) provides specific bacterial strains with an advantage for colonizing the infant intestine. These same effects are seen in infants after GOS consumption, however GOS are very complex mixtures and the underlying molecular mechanisms of how GOS mimic HMOs are relatively unknown. Here we studied the effects of GOS utilization on a prominent gut symbiont, Bacteroides thetaiotaomicron, which has been previously shown to consume HMOs via mucin O-glycan degradation pathways. We show that several pathways for targeting O-mucin glycans are activated in B. thetaiotaomicron by GOS, as well as the galactan utilization sytem. Characterization of the endo-galactanase from this system identified activity on various longer GOS substrates while a subset of GOS compounds were identified as potential activators of mucin glycan metabolism in B. thetaiotaomicron. Our results show that GOS functions as an inducer of mucin-glycan pathways while providing a nutrient source in the form of β-(1 → 4)-galactan. These metabolic features of GOS mixtures may serve to explain the beneficial effects that are seen for GOS supplemented infant formula. PMID:28091546

  6. Characterization of certain proteinase isoenzymes produced by benign and virulent strains of Bacteroides nodosus.

    Science.gov (United States)

    Green, R S

    1985-11-01

    Three proteinase isoenzymes from one benign strain of Bacteroides nodosus and five proteinase isoenzymes from each of two virulent strains of B. nodosus were purified by horizontal slab polyacrylamide gel electrophoresis. The purified isoenzymes hydrolysed casein, collagen I, collagen III, elastin, alpha-elastin, fibrinogen, gelatin, haemoglobin and alpha-keratin. The pH optima of all the isoenzymes lay between 7.25 and 9.5, the range of 8.75-9.25 being common to all. The isoenzymes were inhibited by phenylmethylsulphonyl fluoride, diphenylcarbamyl chloride, L-(1-tosylamide-2-phenyl)ethyl chloromethyl ketone, EGTA and EDTA, indicating that they were chymotrypsin-like serine proteinases that require a metal ion for stability or activity. EDTA inhibition was not reversed by addition of Ca2+ or Mg2+. Some isoenzymes were activated by Mg2+, Ca2+, Cr3+ and Se4+ and all were inhibited by Fe2+, Co2+, Cu2+, Zn2+, Cd2+ and Hg2+. Isoenzymes from benign strains had a lower temperature stability, losing all activity at 55 degrees C, whereas those from virulent strains lost all activity at 60 degrees C.

  7. Study of Dientamoeba Fragilis by Iron Hematoxylin Staining and Nested-PCR Methods in Chalous Healthcare Refers

    Directory of Open Access Journals (Sweden)

    Alizadeh Shargh SH

    2011-01-01

    Full Text Available Bachground and objectives: Dientamoeba fragilis is a habitant protozoa inhuman colon causing clinical symptoms, such as local stomach pain, weightloss, lack of appetite and flatulence. It is important to diagnose this infectioncorrectly and differentiate it from other Protozoa. In this study PCR and IronHematoxylin methods were used to detection of this protozoa in ChalousMedical centers refers in 2010.Material and Methods: The stool samples (n=302 of this cross-sectionalstudy were selected via cluster random sampling. After wet mount study thesamples were preserved in PVA (for staining and Ethanol (for molecular.The samples were studied both Staining and Molecular methods. Sensitivityand specificity were assessed.Results: Of 302 samples, six of them are positive via staining method (1.99%and five by molecular method. All negative results with staining method arealso negative with PCR. Contamination with E.coli in 2 samples and withBalstocystis homonis were seen in one sample. Sensitivity and specificity ofPCR was 85% and 100% respectively.Conclusion: The discrepancy between two methods maybe caused byobserver errors in staining method and unsynchronized molecular andmicroscopic studies.Key words: Dientamoeba, Polymerase Chain Reaction, Hematoxylin, Chalousregion

  8. Epitope identification for a panel of anti-Sinorhizobium meliloti monoclonal antibodies and application to the analysis of K antigens and lipopolysaccharides from bacteroids

    Energy Technology Data Exchange (ETDEWEB)

    Reuhs, B.L.; Stephens, S.B.; Geller, D.P.; Kim, J.S.; Glenn, J.; Przytycki, J.; Ojanen-Reuhs, T.

    1999-11-01

    In two published reports using monoclonal antibodies (MAbs) generated against whole cells, Olsen et al. showed that strain-specific antigens on the surface of cultured cells of Sinorhyzobium meliloti were diminished or absent in the endophytic cells (bacteroids) recovered from alfalfa nodules, whereas two common antigens were not affected by bacterial differentiation. The nature of the antigens, however, were not determined in those studies. For this report, the epitopes for five of the anti-S. meliloti MAbs were identified by polyacrylamide gel electrophoresis-immunoblot analyses of the polysaccharides extracted from S. meliloti and Sinorhizobium fridii. This showed that the strain-specific MAbs recognized K antigens, whereas the strain-cross-reactive MAbs recognized the lipopolysaccharide (LPS) core. The MAbs were then used in the analysis of the LPS and K antigens extracted from S. meliloti bacteroids, which had been recovered from the root nodules of alfalfa, and the results supported the findings of Olsen et al. The size range of the K antigens from bacteroids of S. meliloti NRG247 on polyacrylamide gels was altered, and the epitope was greatly diminished in abundance compared to those from the cultured cells, and no K antigens were detected in the S. meliloti NRG185 bacteroid extract. In contrast to the K antigens, the LPS core appeared to be similar in both cultured cells and bacteroids, although a higher proportion of the LPS fractionated into the organic phase during the phenol-water extraction of the bacteroid polysaccharides. Importantly, immunoblot analysis with an anti-LPS MAb showed that smooth LPS production was modified in the bacteroids.

  9. Coculture fermentations of Bifidobacterium species and Bacteroides thetaiotaomicron reveal a mechanistic insight into the prebiotic effect of inulin-type fructans.

    Science.gov (United States)

    Falony, Gwen; Calmeyn, Thomas; Leroy, Frédéric; De Vuyst, Luc

    2009-04-01

    Four bifidobacteria, each representing a cluster of strains with specific inulin-type-fructan degradation capacities, were grown in coculture fermentations with Bacteroides thetaiotaomicron LMG 11262, a strain able to metabolize both oligofructose and inulin. In a medium for colon bacteria with inulin as the sole added energy source, the ability of the bifidobacteria to compete for this substrate reflected phenotypical variation. Bifidobacterium breve Yakult, a strain that was not able to degrade oligofructose or inulin, was outcompeted by B. thetaiotaomicron LMG 11262. Bifidobacterium adolescentis LMG 10734, a strain that could degrade oligofructose (displaying a preferential breakdown mechanism) but that did not grow on inulin, managed to become competitive when oligofructose and short fractions of inulin started to accumulate in the fermentation medium. Bifidobacterium angulatum LMG 11039(T), a strain that was previously shown to degrade all oligofructose fractions simultaneously and to be able to partially break down inulin, was competitive from the beginning of the fermentation, consuming short fractions of inulin from the moment they appeared. Bifidobacterium longum LMG 11047, representing a cluster of bifidobacteria that shared both high fructose consumption and oligofructose degradation rates and were able to perform partial breakdown of inulin, was the dominating strain in a coculture with B. thetaiotaomicron LMG 11262. These observations indicate that distinct subgroups within the large-intestinal Bifidobacterium population will be stimulated by different groups of prebiotic inulin-type fructans, a variation that could be reflected in differences concerning their health-promoting effects.

  10. Loss of NHE3 alters gut microbiota composition and influences Bacteroides thetaiotaomicron growth.

    Science.gov (United States)

    Engevik, Melinda A; Aihara, Eitaro; Montrose, Marshall H; Shull, Gary E; Hassett, Daniel J; Worrell, Roger T

    2013-11-15

    Changes in the intestinal microbiota have been linked to diabetes, obesity, inflammatory bowel disease, and Clostridium difficile (C. difficile)-associated disease. Despite this, it remains unclear how the intestinal environment, set by ion transport, affects luminal and mucosa-associated bacterial composition. Na(+)/H(+)-exchanger isoform 3 (NHE3), a target of C. difficile toxin B, plays an integral role in intestinal Na(+) absorption. Thus the NHE3-deficient mouse model was chosen to examine the effect of pH and ion composition on bacterial growth. We hypothesized that ion transport-induced change in the intestinal environment would lead to alteration of the microbiota. Region-specific changes in ion composition and pH correlated with region-specific alteration of luminal and mucosal-associated bacteria with general decreases in Firmicutes and increases in Bacteroidetes members. Bacteroides thetaiotaomicron (B. thetaiotaomicron) increased in NHE3(-/-) terminal ileum and was examined in vitro to determine whether altered Na(+) was sufficient to affect growth. Increased in vitro growth of B. thetaiotaomicron occurred in 43 mM Na(+) correlating with the NHE3(-/-) mouse terminal ileum [Na(+)]. NHE3(-/-) terminal ileum displayed increased fut2 mRNA and fucosylation correlating with B. thetaiotaomicron growth. Inoculation of B. thetaiotaomicron in wild-type and NHE3(-/-) terminal ileum organoids displayed increased fut2 and fucosylation, indicating that B. thetaiotaomicron alone is sufficient for the increased fucosylation seen in vivo. These data demonstrate that loss of NHE3 alters the intestinal environment, leading to region-specific changes in bacteria, and shed light on the growth requirements of some gut microbiota members, which is vital for creating better treatments of complex diseases with an altered gut microbiota.

  11. Estabishment of techniques for gene replacement in Kluyveromyces fragilis%脆壁克鲁维酵母基因置换技术的建立

    Institute of Scientific and Technical Information of China (English)

    李杰; 曹宇婷; 徐欣; 张旭; 李璐; 吕洋; 卢松冲

    2013-01-01

    To estibish the homologous recombination and electroporation system in Kluyverom-yces fragilis, we constructed the plasmid pPkan was coustucted which with Homologous arms of the UAS of lactase gene from lactase product strain. Paper studied the effects of growth phase of cel s, electric para-meters, cultured time after electroporation on transformation efficiency. At the same time, we studied the relation that combined the electroporation with REMI. The result indicated that an efficient and stable system of electroporation in Kluyveromyces fragilis had been developed, providing a powerful tool for the transgenic research of Kluyveromyces fragilis. The results showed that a high transformation efficiency was achieved in Kluyveromyces fragilis cels at mid-log growth phase electroporated with voltage, electric intensity 7.5 kV·cm-1 and cultured time after electroporation was 90 min. However, when restriction enzyme was added to electroporation system at 10 μL, the transformation efficiency was not increased. And 87.5% of positive transformants was homologous recombination.%  以中性乳糖酶生产菌脆壁克鲁维酵母为材料,构建以kan基因为筛选标记、以脆壁克鲁维酵母乳糖酶基因上游调控区为同源臂的质粒pPkan.将质粒pPkan电击转化脆壁克鲁维酵母,对受体菌生长时期、电场强度、电击后培养时间等条件进行优化.结果表明,以OD600为0.8的脆壁克鲁维酵母为受体、电压1.5 kV、电场强度为7.5 kV·cm-1、电击后培养时间为90 min,可获得较高的转化率,最高转化效率为2.37×102转化子·μgDNA.在电击转化的同时加入限制性内切酶10μL,对电击转化的转化率无显著影响.经PCR筛选证实87.5%的转化子为同源重组,从而建立一套有效的脆壁克鲁维酵母基因置换技术.

  12. A method of obtaining dietary data for slow worms (Anguis fragilis) by means of non-harmful cooling and results from a Danish population

    DEFF Research Database (Denmark)

    Pedersen, Iben; Jensen, Jan Kjærgaard; Toft, Søren

    2009-01-01

    Diet composition of slow worms (Anguis fragilis) from a Danish population was recorded from May to September 2006. Slow worms were maintained in cool conditions (at 8°C) for a maximum of 126 h, which made approximately half of the animals regurgitate. The method worked equally well on juveniles...... and adults. The regurgitations revealed that the slow worms preyed on small snails, slugs, pill millipedes (Glomeris marginata), earthworms and Lepidoptera larvae. There were seasonal changes in taxon composition of the diet but no ontogenetic or sex-related differences. The food quality of selected prey...

  13. The structure of BVU2987 from Bacteroides vulgatus reveals a superfamily of bacterial periplasmic proteins with possible inhibitory function

    OpenAIRE

    2010-01-01

    Proteins that contain the DUF2874 domain constitute a new Pfam family PF11396. Members of this family have predominantly been identified in microbes found in the human gut and oral cavity. The crystal structure of one member of this family, BVU2987 from Bacteroides vulgatus, has been determined, revealing a β-lactamase inhibitor protein-like structure with a tandem repeat of domains. Sequence analysis and structural comparisons reveal that BVU2987 and other DUF2874 proteins are related to β-l...

  14. The structure of BVU2987 from Bacteroides vulgatus reveals a superfamily of bacterial periplasmic proteins with possible inhibitory function.

    Science.gov (United States)

    Das, Debanu; Finn, Robert D; Carlton, Dennis; Miller, Mitchell D; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L; Bakolitsa, Constantina; Chen, Connie; Chiu, Hsiu Ju; Chiu, Michelle; Clayton, Thomas; Deller, Marc C; Duan, Lian; Ellrott, Kyle; Ernst, Dustin; Farr, Carol L; Feuerhelm, Julie; Grant, Joanna C; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K; Klock, Heath E; Knuth, Mark W; Kozbial, Piotr; Krishna, S Sri; Kumar, Abhinav; Marciano, David; McMullan, Daniel; Morse, Andrew T; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Rife, Christopher L; Sefcovic, Natasha; Tien, Henry J; Trame, Christine B; van den Bedem, Henry; Weekes, Dana; Wooten, Tiffany; Xu, Qingping; Hodgson, Keith O; Wooley, John; Elsliger, Marc André; Deacon, Ashley M; Godzik, Adam; Lesley, Scott A; Wilson, Ian A

    2010-10-01

    Proteins that contain the DUF2874 domain constitute a new Pfam family PF11396. Members of this family have predominantly been identified in microbes found in the human gut and oral cavity. The crystal structure of one member of this family, BVU2987 from Bacteroides vulgatus, has been determined, revealing a β-lactamase inhibitor protein-like structure with a tandem repeat of domains. Sequence analysis and structural comparisons reveal that BVU2987 and other DUF2874 proteins are related to β-lactamase inhibitor protein, PepSY and SmpA_OmlA proteins and hence are likely to function as inhibitory proteins.

  15. Overexpression of BetS, a Sinorhizobium meliloti high-affinity betaine transporter, in bacteroids from Medicago sativa nodules sustains nitrogen fixation during early salt stress adaptation.

    Science.gov (United States)

    Boscari, Alexandre; Van de Sype, Ghislaine; Le Rudulier, Daniel; Mandon, Karine

    2006-08-01

    Sinorhizobium meliloti possesses several betaine transporters to cope with salt stress, and BetS represents a crucial high-affinity glycine and proline betaine uptake system involved in the rapid acquisition of betaines by cells subjected to osmotic upshock. Using a transcriptional lacZ (beta-galactosidase) fusion, we showed that betS is expressed during the establishment of the symbiosis and in mature nitrogen-fixing nodules. However, neither Nod nor Fix phenotypes were impaired in a betS mutant. BetS is functional in isolated bacteroids, and its activity is strongly activated by high osmolarity. In bacteroids from a betS mutant, glycine betaine and proline betaine uptake was reduced by 85 to 65%, indicating that BetS is a major component of the overall betaine uptake activity in bacteroids in response to osmotic stress. Upon betS overexpression (strain UNA349) in free-living cells, glycine betaine transport was 2.3-fold higher than in the wild-type strain. Interestingly, the accumulation of proline betaine, the endogenous betaine synthesized by alfalfa plants, was 41% higher in UNA349 bacteroids from alfalfa plants subjected to 1 week of salinization (0.3 M NaCl) than in wild-type bacteroids. In parallel, a much better maintenance of nitrogen fixation activity was observed in 7-day-salinized plants nodulated with the overexpressing strain than in wild-type nodulated plants. Taken altogether, these results are consistent with the major role of BetS as an emergency system involved in the rapid uptake of betaines in isolated and in planta osmotically stressed bacteroids of S. meliloti.

  16. Novel Probiotic Therapies for Autism

    Science.gov (United States)

    2013-09-01

    commensal Bacteroides fragilis corrects gut permeability and ameliorates defects in communicative, stereotypic, anxiety-like and sensorimotor behaviors...2010; Hooper et al., 2012). In particular, the human commensal Bacteroides fragilis exhibits therapeutic properties in mouse models of both...colitis and multiple sclerosis (MS) (Ochoa-Reparaz et al., 2010; Round et al., 2010). Therefore, we are exploring the utility of commensal bacteria in

  17. Bacteroides intestinalis DSM 17393, a member of the human colonic microbiome, upregulates multiple endoxylanases during growth on xylan

    Science.gov (United States)

    Wang, Kui; Pereira, Gabriel V.; Cavalcante, Janaina J. V.; Zhang, Meiling; Mackie, Roderick; Cann, Isaac

    2016-01-01

    Many human diets contain arabinoxylan, and the ease of genome sequencing coupled with reduced cost have led to unraveling the arsenal of genes utilized by the colonic Bacteroidetes to depolymerize this polysaccharide. The colonic Bacteroidetes with potential to ferment arabinoxylans include Bacteroides intestinalis. In this study, we analyzed the hydrolytic activities of members of a xylan degradation cluster encoded on the genome of Bacteroides intestinalis DSM 17393. Here, it is demonstrated that a cocktail of the xylanolytic enzymes completely hydrolyze arabinoxylans found in human diets. We show that this bacterium and relatives have evolved and secrete a unique bifunctional endoxylanase/arabinofuranosidase in the same polypeptide. The bifunctional enzyme and other secreted enzymes attack the polysaccharides extracellularly to remove the side-chains, exposing the xylan backbone for cleavage to xylo-oligosaccharides and xylose. These end products are transported into the cell where a β-xylosidase cleaves the oligosaccharides to fermentable sugars. While our experiments focused on B. intestinalis, it is likely that the extracellular enzymes also release nutrients to members of the colonic microbial community that practice cross-feeding. The presence of the genes characterized in this study in other colonic Bacteroidetes suggests a conserved strategy for energy acquisition from arabinoxylan, a component of human diets. PMID:27681607

  18. Structures of complexes of a metal-independent glycosyltransferase GT6 from Bacteroides ovatus with UDP-N-acetylgalactosamine (UDP-GalNAc) and its hydrolysis products.

    Science.gov (United States)

    Pham, Tram T K; Stinson, Brittany; Thiyagarajan, Nethaji; Lizotte-Waniewski, Michelle; Brew, Keith; Acharya, K Ravi

    2014-03-21

    Mammalian members of glycosyltransferase family 6 (GT6) of the CAZy database have a GT-A fold containing a conserved Asp-X-Asp (DXD) sequence that binds an essential metal cofactor. Bacteroides ovatus GT6a represents a GT6 clade found in more than 30 Gram-negative bacteria that is similar in sequence to the catalytic domains of mammalian GT6, but has an Asn(95)-Ala-Asn(97) (NXN) sequence substituted for the DXD motif and metal-independent catalytic activity. Co-crystals of a low activity mutant of BoGT6a (E192Q) with UDP-GalNAc contained protein complexes with intact UDP-GalNAc and two forms with hydrolysis products (UDP plus GalNAc) representing an initial closed complex and later open form primed for product release. Two cationic residues near the C terminus of BoGT6a, Lys(231) and Arg(243), interact with the diphosphate moiety of UDP-GalNAc, but only Lys(231) interacts with the UDP product and may function in leaving group stabilization. The amide group of Asn(95), the first Asn of the NXN motif, interacts with the ribose moiety of the substrate. This metal-independent GT6 resembles its metal-dependent homologs in undergoing conformational changes on binding UDP-GalNAc that arise from structuring the C terminus to cover this substrate. It appears that in the GT6 family, the metal cofactor functions specifically in binding the UDP moiety in the donor substrate and transition state, actions that can be efficiently performed by components of the polypeptide chain.

  19. Probabilistic analysis showing that a combination of bacteroides and methanobrevibacter source tracking markers is effective for identifying waters contaminated by human fecal pollution

    Science.gov (United States)

    Johnston, Christopher; Byappanahalli, Muruleedhara N.; Gibson, Jacqueline MacDonald; Ufnar, Jennifer A.; Whitman, Richard L.; Stewart, Jill R.

    2013-01-01

    Microbial source tracking assays to identify sources of waterborne contamination typically target genetic markers of host-specific microorganisms. However, no bacterial marker has been shown to be 100% host-specific, and cross-reactivity has been noted in studies evaluating known source samples. Using 485 challenge samples from 20 different human and animal fecal sources, this study evaluated microbial source tracking markers including the Bacteroides HF183 16S rRNA, M. smithii nifH, and Enterococcus esp gene targets that have been proposed as potential indicators of human fecal contamination. Bayes' Theorem was used to calculate the conditional probability that these markers or a combination of markers can correctly identify human sources of fecal pollution. All three human-associated markers were detected in 100% of the sewage samples analyzed. Bacteroides HF183 was the most effective marker for determining whether contamination was specifically from a human source, and greater than 98% certainty that contamination was from a human source was shown when both Bacteroides HF183 and M. smithii nifH markers were present. A high degree of certainty was attained even in cases where the prior probability of human fecal contamination was as low as 8.5%. The combination of Bacteroides HF183 and M. smithii nifH source tracking markers can help identify surface waters impacted by human fecal contamination, information useful for prioritizing restoration activities or assessing health risks from exposure to contaminated waters.

  20. Nitrogen Fixation (C(2)H(2) Reduction) by Broad Bean (Vicia faba L.) Nodules and Bacteroids under Water-Restricted Conditions.

    Science.gov (United States)

    Guerin, V; Trinchant, J C; Rigaud, J

    1990-03-01

    Water potentials of leaves and nodules of broad bean (Vicia faba L.) cultivated on a sandy mixture were linearly and highly (r(2) = 0.99) correlated throughout a water deprivation of plants. A decrease of 0.2 megapascal of the nodule water potential (Psi(nod)) induced an immediate 25% inhibition of the highest level of acetylene reduction of broad bean nodules attached to roots. This activity continued to be depressed when water stress increased, but the effect was less pronounced. Partial recovery of optimal C(2)H(2) reduction capacity of mildly water stressed nodules (Psi(nod) = -1.2 megapascals) was possible by increasing the external O(2) partial pressure up to 60 kilopascals. The dense packing of the cortical cells of nodules may be responsible for the limitation of O(2) diffusion to the central tissue. Bacteroids isolated from broad bean nodules exhibited higher N(2) fixation activity with glucose than with succinate as an energy-yielding substrate. Bacteroids from stressed nodules appeared more sensitive to O(2), and their optimal activity declined with increasing nodule water deprivation. This effect could be partly due to decreased bacteroid respiration capacity with water stress. Water stress was also responsible for a decrease of the cytosolic protein content of the nodule and more specifically of leghemoglobin. The alteration of the bacteroid environment appears to contribute to the decline in N(2) fixation under water restricted conditions.

  1. High-resolution transcriptomic analyses of Sinorhizobium sp. NGR234 bacteroids in determinate nodules of Vigna unguiculata and indeterminate nodules of Leucaena leucocephala.

    Science.gov (United States)

    Li, Yan; Tian, Chang Fu; Chen, Wen Feng; Wang, Lei; Sui, Xin Hua; Chen, Wen Xin

    2013-01-01

    The rhizobium-legume symbiosis is a model system for studying mutualistic interactions between bacteria and eukaryotes. Sinorhizobium sp. NGR234 is distinguished by its ability to form either indeterminate nodules or determinate nodules with diverse legumes. Here, we presented a high-resolution RNA-seq transcriptomic analysis of NGR234 bacteroids in indeterminate nodules of Leucaena leucocephala and determinate nodules of Vigna unguiculata. In contrast to exponentially growing free-living bacteria, non-growing bacteroids from both legumes recruited several common cellular functions such as cbb3 oxidase, thiamine biosynthesis, nitrate reduction pathway (NO-producing), succinate metabolism, PHB (poly-3-hydroxybutyrate) biosynthesis and phosphate/phosphonate transporters. However, different transcription profiles between bacteroids from two legumes were also uncovered for genes involved in the biosynthesis of exopolysaccharides, lipopolysaccharides, T3SS (type three secretion system) and effector proteins, cytochrome bd ubiquinol oxidase, PQQ (pyrroloquinoline quinone), cytochrome c550, pseudoazurin, biotin, phasins and glycolate oxidase, and in the metabolism of glutamate and phenylalanine. Noteworthy were the distinct expression patterns of genes encoding phasins, which are thought to be involved in regulating the surface/volume ratio of PHB granules. These patterns are in good agreement with the observed granule size difference between bacteroids from L. leucocephala and V. unguiculata.

  2. De Novo Alanine Synthesis by Bacteroids of Mesorhizobium loti Is Not Required for Nitrogen Transfer in the Determinate Nodules of Lotus corniculatus

    OpenAIRE

    Kumar, Shalini; Bourdès, Alexandre; Poole, Philip

    2005-01-01

    Deletion of both alanine dehydrogenase genes (aldA) in Mesorhizobium loti resulted in the loss of AldA enzyme activity from cultured bacteria and bacteroids but had no effect on the symbiotic performance of Lotus corniculatus plants. Thus, neither indeterminate pea nodules nor determinate L. corniculatus nodules export alanine as the sole nitrogen secretion product.

  3. De novo alanine synthesis by bacteroids of Mesorhizobium loti is not required for nitrogen transfer in the determinate nodules of Lotus corniculatus.

    Science.gov (United States)

    Kumar, Shalini; Bourdès, Alexandre; Poole, Philip

    2005-08-01

    Deletion of both alanine dehydrogenase genes (aldA) in Mesorhizobium loti resulted in the loss of AldA enzyme activity from cultured bacteria and bacteroids but had no effect on the symbiotic performance of Lotus corniculatus plants. Thus, neither indeterminate pea nodules nor determinate L. corniculatus nodules export alanine as the sole nitrogen secretion product.

  4. Improved Multiplex PCR Using Conserved and Species-Specific 16S rRNA Gene Primers for Simultaneous Detection of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, and Porphyromonas gingivalis

    OpenAIRE

    Tran, Simon Dangtuan; Rudney, Joel. D.

    1999-01-01

    Among putative periodontal pathogens, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, and Porphyromonas gingivalis are most convincingly implicated as etiological agents in periodontitis. Therefore, techniques for detection of those three species would be of value. We previously published a description of a multiplex PCR that detects A. actinomycetemcomitans and P. gingivalis. The present paper presents an improvement on that technique, which now allows more sensitive detection o...

  5. The type 4 pilin of Moraxella nonliquefaciens exhibits unique similarities with the pilins of Neisseria gonorrhoeae and Dichelobacter (Bacteroides) nodosus.

    Science.gov (United States)

    Tønjum, T; Marrs, C F; Rozsa, F; Bøvre, K

    1991-10-01

    Moraxella nonliquefaciens is a bacterium which is part of the normal flora of the human upper respiratory tract and is an occasional cause of disease. Using a previously cloned type 4 pilin gene (tfpQ) from Moraxella bovis as a hybridization probe, we have cloned an 826 bp Sau3 AI fragment which contains an M. nonliquefaciens type 4 pilin gene (tfpA) from strain NCTC 7784. The pilin gene is expressed in Escherichia coli. We have examined NCTC 7784 and nine other M. nonliquefaciens strains by genomic Southern hybridization using tfpA as a probe, and they all appeared to have more than one pilin gene. While the predicted amino acid sequence of the M. nonliquefaciens tfpA pilin has conserved regions as compared to pilins of M. bovis and M. lacunata, it also shows similarities to both the type 4 pilin of Neisseria gonorrhoeae and the type 4 pilin of Dichelobacter nodosus (formerly Bacteroides nodosus).

  6. Fluorescence studies with malate dehydrogenase from rhizobium japonicum 3I1B-143 bacteroids: a two-tryptophan containing protein

    Science.gov (United States)

    Ghiron, Camillo A.; Eftink, Maurice R.; Waters, James K.; Emerich, David W.

    1990-05-01

    A number of fluorescence studies, both of trp residues and bound NADH, have been reported for porcine MDH. The large number of trp residues (6) complicates the interpretation of some studies. To circumvent this we have performed studies with a two tryptophan (per subunit) MDH from Rhizobium japonicum 311B-143 bacteroids. We have performed phase/modulation fluorescence lifetime measurements, as a function of temperature and added quencher KI, in order to resolved the 1.3 ns (blue) and 6.6 ns (red) contributions from the two classes of trp residues. Anisotropy decay studies have also been performed. The binding of NADH dynamically quenches the fluorescence of both tip residues, but, unlike mammalian cytoplasmic and mitochondrial MDH, there is not a large enhancement in fluorescence of bound NADH upon forming a ternary complex with either tartronic acid or D-malonate.

  7. Bacteroides uniformis is a putative bacterial species associated with the degradation of the isoflavone genistein in human feces.

    Science.gov (United States)

    Renouf, Mathieu; Hendrich, Suzanne

    2011-06-01

    Inter-individual variation in isoflavone absorption depends on gut microbial degradation and affects the efficacy of these compounds. We hypothesized that inter-individual variation in fecal isoflavone disappearance coincided with variation in bacterial species. In vitro anaerobic fecal disappearance of isoflavones was measured from 33 participants by HPLC. Fecal microbial 16S rRNA variable region PCR products were obtained from 4 participants with the greatest and least genistein or glycitein degradation and were subjected to denaturing gradient gel electrophoresis. DNA bands with a homology of 90-95% to Bacteroides uniformis and Faecalibacterium prausnitzii were present in greater intensities in fecal samples showing a genistein disappearance rate constant of 1.47 ± 0.14 h(-1) compared with those with a genistein disappearance rate constant of 0.15 ± 0.03 h(-1) (P < 0.05). Human fecal bacterial species with DNA sequences 90-100% homologous to Tannerella forsythensis and 4 other species were present in greater intensities in fecal samples showing a glycitein disappearance rate constant of 0.57 ± 0.30 h(-1) compared with fecal samples with a glycitein disappearance rate constant of 0.08 ± 0.03 h(-1) (P < 0.05). In high degraders, B. uniformis may be a candidate for genistein degradation and T. forsythensis for glycitein degradation, based on fecal isoflavone degradation in the presence of these species. Bacteroides acidifaciens increased isoflavone disappearance in anaerobic human fecal incubations under nutrient-rich and -depleted conditions, suggesting this species as one responsible for the generally high degradation of isoflavones by humans. These fecal microbes are candidate biomarkers for interindividual variation in isoflavone uptake and efficacy.

  8. Could gut microbiota serve as prognostic biomarker associated with colorectal cancer patients' survival? A pilot study on relevant mechanism

    Science.gov (United States)

    Wei, Zhiliang; Cao, Shougen; Liu, Shanglong; Yao, Zengwu; Sun, Teng; Li, Yi; Li, Jiante; Zhang, Dongfeng; Zhou, Yanbing

    2016-01-01

    Evidences have shown that dysbiosis could promote the progression of colorectal cancer (CRC). However, the association of dysbiosis and prognosis of CRC is barely investigated. Therefore, we used 16S rRNA gene sequencing approach to determine differences in microbiota among tumor tissues of different prognosis and found that Fusobacterium nucleatum and Bacteroides fragilis were more abundant in worse prognosis groups, while Faecalibacterium prausnitzii displayed higher abundance in survival group. To further explore the prognostic value of the found bacteria, Kaplan–Meier and Cox proportional regression analyses were used and the results exhibited that high abundance of F. nucleatum and B. fragilis were independent indicators of poor patient's survival. Besides, the expression of major inflammatory mediator were analyzed using PCR and western blot methods, and it turned out that high abundance of F. nucleatum was associated with increased expression of TNF-α, β-catenin and NF-κB, while COX-2, MMP-9 and NF-κB were positively related with high B. fragilis level, and high level of F. prausnitzii showed lower expression of β-catenin, MMP-9 and NF-κB. Moreover, immunohistochemical analysis indicated that KRAS and BRAF expression were prominent in F. nucleatum and B. fragilis high abundance group, while MLH1 showed lower expression. In conclusion, F. nucleatum, B. fragilis and F. prausnitzii can be identified as useful prognostic biomarkers for CRC, and dysbiosis might worsen the patients' prognosis by up-regulating gut inflammation level. PMID:27323816

  9. The Selection of Optimal Medium and Condition for the Production of Lac tase by Yeast Kluyvermyces fragilis%产乳糖酶酵母Kluyveromyces fragilis株培养 产酶发酵条件的优化

    Institute of Scientific and Technical Information of China (English)

    丁倩; 蒋燕灵; 邵靖宇

    2001-01-01

    目的:为进一步提高产乳糖酶酵母Kluyveromyces fragilis(K.fragilis)株的酶产量,对该菌株的培养产酶发酵条件进行优化试验。方法:采用增殖和诱导二步培养法培养酵母K.fragilis株,并采用单因素试验方法分析碳源、氮源对酵母诱导产酶的影响。结果:确定了K.fragilis酵母株诱导培养的较佳配方,当乳糖浓度为120g/L,醋酸铵浓度为5g/L,pH为6.7时,单位酶产量达122.4IU/ml培养液。结论:该菌株生长产酶情况良好,具有较高的应用价值。%Objective: To study the optimal condition on lactase production by yeast Kluyveromyces fragilis(K.fragilis) to increase the enzyme productivity.Methods: With separated proliferation and induction culture,the effe cts of carbon source and nitrogen source on yeast proliferation and lactase indu ction were studied by the method of monofactorial analysis.Results: The optimum medium for the productivity of lactase by K.f ragilis was determined.Maximal enzyme activity (122.4 IU/ml) was reached when the concentration of lactose was 12%,ammonium acetate was 0.5% and pH 6.7.Conclusion: The results of this experiment demonstrate that this str ain will be good for industrial production.

  10. Suppurative otitis and ascending meningoencephalitis associated with Bacteroides tectus and Porphyromonas gulae in a captive Parma wallaby (Macropus parma) with toxoplasmosis.

    Science.gov (United States)

    Giannitti, Federico; Schapira, Andrea; Anderson, Mark; Clothier, Kristin

    2014-09-01

    A 6-year-old female Parma wallaby (Macropus parma) at a zoo in California developed acute ataxia and left-sided circling. Despite intensive care, clinical signs progressed to incoordination and prostration, and the animal was euthanized. At necropsy, the left tympanic cavity was filled with homogeneous suppurative exudate that extended into the cranium expanding the meninges and neuroparenchyma in the lateral and ventral aspect of the caudal ipsilateral brainstem and medulla oblongata. Microscopically, the brainstem showed regional severe suppurative meningoencephalitis with large numbers of neutrophils, fewer macrophages, and lymphocytes admixed with fibrin, necrotic cellular debris, hemorrhage, and mineralization, with numerous intralesional Gram-negative bacilli. Bacteroides spp. and Porphyromonas spp. were isolated on anaerobic culture from the meninges, and the bacteria were further characterized by partial 16S ribosomal RNA gene sequencing as Bacteroides tectus and Porphyromonas gulae. Bacterial aerobic culture from the meninges yielded very low numbers of mixed flora and Proteus spp., which were considered contaminants. Culture of Mycoplasma spp. from middle ear and meninges was negative. Additionally, Toxoplasma gondii cysts were detected by immunohistochemistry in the heart and brain, and anti-Toxoplasma antibodies were detected in serum. The genera Bacteroides and Porphyromonas have been associated with oral disease in marsupials; but not with otitis and meningoencephalitis. The results of the present work highlight the importance of performing anaerobic cultures in the diagnostic investigation of cases of suppurative otitis and meningoencephalitis in macropods.

  11. BacS: an abundant bacteroid protein in Rhizobium etli whose expression ex planta requires nifA.

    Science.gov (United States)

    Jahn, Olivia J; Davila, Guillermo; Romero, David; Noel, K Dale

    2003-01-01

    Rhizobium etli CFN42 bacteroids from bean nodules possessed an abundant 16-kDa protein (BacS) that was found in the membrane pellet after cell disruption. This protein was not detected in bacteria cultured in tryptone-yeast extract. In minimal media, it was produced at low oxygen concentration but not in a mutant whose nifA was disrupted. N-terminal sequencing of the protein led to isolation of a bacS DNA fragment. DNA hybridization and nucleotide sequencing revealed three copies of the bacS gene, all residing on the main symbiotic plasmid of strain CFN42. A stretch of 304 nucleotides, exactly conserved upstream of all three bacS open reading frames, had very close matches with the NifA and sigma 54 consensus binding sequences. The only bacS homology in the genetic sequence databases was to three hypothetical proteins of unknown function, all from rhizobial species. Mutation and genetic complementation indicated that each of the bacS genes gives rise to a BacS polypeptide. Mutants disrupted or deleted in all three genes did not produce the BacS polypeptide but were Nod+ and Fix+ on Phaseolus vulgaris.

  12. The reduction of murine norovirus 1, B. fragilis HSP40 infecting phage B40-8 and E. coli after a mild thermal pasteurization process of raspberry puree.

    Science.gov (United States)

    Baert, L; Uyttendaele, M; Van Coillie, E; Debevere, J

    2008-10-01

    Pasteurization processes of raspberry puree are nowadays limited to short times and rather low temperatures to maintain flavor and nutritional quality. Norovirus (NoV) outbreaks associated with raspberries highlight the need to determine the survival of NoV on this type of soft fruit. Therefore, resistance of murine norovirus 1 (MNV-1), a surrogate for human NoV, B. fragilis HSP40 infecting phage B40-8, and E. coli towards mild pasteurization was tested. Raspberry puree heat treated at 65 degrees C for 30s showed a 1.86, 2.77, and 3.89 log reduction of, respectively, MNV-1, E. coli, and B40-8. Heating at 75 degrees C for 15s established a 2.81 log reduction of MNV-1 while a 3.44 and 3.61 log reduction of B40-8 and E. coli was observed. No supplementary lethal effect of holding the heat-treated raspberry puree at 4 degrees C overnight was noticed. B40-8 failed to be useful as a tool to monitor NoV inactivation during mild pasteurization processes. Moreover, pasteurized raspberry puree.

  13. Cloacal aerobic bacterial flora and absence of viruses in free-living slow worms (Anguis fragilis), grass snakes (Natrix natrix) and European Adders (Vipera berus) from Germany.

    Science.gov (United States)

    Schmidt, Volker; Mock, Ronja; Burgkhardt, Eileen; Junghanns, Anja; Ortlieb, Falk; Szabo, Istvan; Marschang, Rachel; Blindow, Irmgard; Krautwald-Junghanns, Maria-Elisabeth

    2014-12-01

    Disease problems caused by viral or bacterial pathogens are common in reptiles kept in captivity. There is no information available on the incidence of viral pathogens or the physiological cloacal bacterial flora of common free-living reptiles in Germany. Therefore, 56 free-living reptiles including 23 European adders (Vipera berus), 12 grass snakes (Natrix natrix) and 21 slow worms (Anguis fragilis) were investigated on the island Hiddensee in northeastern Germany. Pharyngeal and cloacal swabs were taken immediately after capture. Bacteriological examination was performed from the cloacal swabs to study the aerobic cloacal flora. Molecular biological examination included amplification of DNA or RNA from adeno-, rana- and ferlaviruses as well as culturing on Russell's viper heart cells for virus isolation. Salmonella spp. were isolated from European adders but not from the other reptiles examined. The minimal inhibitory concentration was determined from the isolated Salmonella spp. However, some potentially human pathogenic bacteria, such as Proteus vulgaris, Aeromonas hydrophila, Klebsiella pneumoniae and Escherichia coli were isolated. Viruses were not detected in any of the examined reptiles. To the authors' best knowledge, the present study is the first survey of viral pathogens in free-living snakes and slow worms in Germany and the first survey of cloacal aerobic bacterial flora of slow worms.

  14. Willow (Salix fragilis Linn.): A multipurpose tree species under pest attack in the cold desert of Lahaul valley, northwestern Himalaya, India.

    Science.gov (United States)

    Rawat, Yashwant S; Oinam, Santaram S; Vishvakarma, Subhash C R; Kuniyal, Chandra P; Kuniyal, Jagdish C

    2006-02-01

    Salix fragilis is the most common willow species grown extensively under the indigenous agroforestry system in the cold desert of Lahaul valley located in the northwestern Himalayas, India. Presently, this tree is under severe pest attack, and other infections have made its survival in the area questionable. This deciduous multipurpose tree species provides vegetation cover to the barren landscape of Lahaul and is a significant contributor of fuel and fodder to the region. This study is a detailed profile of the plant in three villages within this region: Khoksar, Jahlma, and Hinsa. The willow provided 69.5%, 29%, and 42% of the total fuelwood requirements of Jahlma, Khoksar, and Hinsa respectively. A striking observation was that only 30.0 +/- 20.1% trees were healthy: 55.2 +/- 16.1% of the willows have dried up and 14.8 +/- 6.1% were in drying condition due to a combination of pest infestation and infection. To sustain this cultivation of willow under the existing agroforestry system in the region, we recommend that locally available wild species and other established varieties of willow growing in similar regions of the Himalayas be introduced on a trial basis.

  15. Identification of Human Intestinal Bacteria that Promote or Inhibit Inflammation

    Science.gov (United States)

    2012-11-01

    Vibrio " cholerae " Proteus"sp." Bacteroides"thetaiotaomicron" Escherichea"coli"(EH)" Escherichea"coli"(HMC)" Bacteroidetes"fragilis...equally  inflammatory  species   Escherichia   coli,   Vibrio   colerae   and   Bacteroides   fragilis.   Similarly,   the...the   equally   inflammatory  species   Vibrio  colerae  and  Bacteroides  fragilis.  These   findings   are  

  16. Degradation of Fructans and Production of Propionic Acid by Bacteroides thetaiotaomicron are Enhanced by the Shortage of Amino Acids.

    Science.gov (United States)

    Adamberg, Signe; Tomson, Katrin; Vija, Heiki; Puurand, Marju; Kabanova, Natalja; Visnapuu, Triinu; Jõgi, Eerik; Alamäe, Tiina; Adamberg, Kaarel

    2014-01-01

    Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory) and levan (synthesized using levansucrase from Pseudomonas syringae), two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (degree of polymerization > 3). Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h), followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of d-lactate (82 ± 33 mmol/gDW) occurred in parallel with extensive consumption (up to 17 mmol/gDW) of amino acids, especially Ser, Thr, and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will

  17. Degradation of fructans and production of propionic acid by Bacteroides thetaiotaomicron are enhanced by shortage of amino acids

    Directory of Open Access Journals (Sweden)

    Signe eAdamberg

    2014-12-01

    Full Text Available Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by the catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory and levan (synthesized using levansucrase from Pseudomonas syringae, two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (DP > 3. Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h, followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of D-lactate (82 ± 33 mmol/gDW occurred in parallel with extensive consumption (up to 17 mmol/gDW of amino acids, especially Ser, Thr and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will be studied in

  18. The colitis-associated transcriptional profile of commensal Bacteroides thetaiotaomicron enhances adaptive immune responses to a bacterial antigen.

    Directory of Open Access Journals (Sweden)

    Jonathan J Hansen

    Full Text Available BACKGROUND: Inflammatory bowel diseases (IBD may be caused in part by aberrant immune responses to commensal intestinal microbes including the well-characterized anaerobic gut commensal Bacteroides thetaiotaomicron (B. theta. Healthy, germ-free HLA-B27 transgenic (Tg rats develop chronic colitis when colonized with complex gut commensal bacteria whereas non-transgenic (nTg rats remain disease-free. However, the role of B. theta in causing disease in Tg rats is unknown nor is much known about how gut microbes respond to host inflammation. METHODS: Tg and nTg rats were monoassociated with a human isolate of B. theta. Colonic inflammation was assessed by histologic scoring and tissue pro-inflammatory cytokine measurement. Whole genome transcriptional profiling of B. theta recovered from ceca was performed using custom GeneChips and data analyzed using dChip, Significance Analysis of Microarrays, and Gene Set Enrichment Analysis (GSEA software. Western Blots were used to determine adaptive immune responses to a differentially expressed B. theta gene. RESULTS: B. theta monoassociated Tg rats, but not nTg or germ-free controls, developed chronic colitis. Transcriptional profiles of cecal B. theta were significantly different in Tg vs. nTg rats. GSEA revealed that genes in KEGG canonical pathways involved in bacterial growth and metabolism were downregulated in B. theta from Tg rats with colitis though luminal bacterial concentrations were unaffected. Bacterial genes in the Gene Ontology molecular function "receptor activity", most of which encode nutrient binding proteins, were significantly upregulated in B. theta from Tg rats and include a SusC homolog that induces adaptive immune responses in Tg rats. CONCLUSIONS: B. theta induces colitis in HLA-B27 Tg rats, which is associated with regulation of bacterial genes in metabolic and nutrient binding pathways that may affect host immune responses. These studies of the host-microbial dialogue may lead to

  19. Bacteroides uniformis CECT 7771 ameliorates metabolic and immunological dysfunction in mice with high-fat-diet induced obesity.

    Directory of Open Access Journals (Sweden)

    Paola Gauffin Cano

    Full Text Available BACKGROUND: Associations have been made between obesity and reduced intestinal numbers of members of the phylum Bacteroidetes, but there is no direct evidence of the role these bacteria play in obesity. Herein, the effects of Bacteroides uniformis CECT 7771 on obesity-related metabolic and immune alterations have been evaluated. METHODS AND FINDINGS: Adult (6-8 week male wild-type C57BL-6 mice were fed a standard diet or a high-fat-diet HFD to induce obesity, supplemented or not with B. uniformis CECT 7771 for seven weeks. Animal weight was monitored and histologic, biochemical, immunocompetent cell functions, and features of the faecal microbiota were analysed after intervention. The oral administration of B. uniformis CECT 7771 reduced body weight gain, liver steatosis and liver cholesterol and triglyceride concentrations and increased small adipocyte numbers in HFD-fed mice. The strain also reduced serum cholesterol, triglyceride, glucose, insulin and leptin levels, and improved oral tolerance to glucose in HFD fed mice. The bacterial strain also reduced dietary fat absorption, as indicated by the reduced number of fat micelles detected in enterocytes. Moreover, B. uniformis CECT 7771 improved immune defence mechanisms, impaired in obesity. HFD-induced obesity led to a decrease in TNF-α production by peritoneal macrophages stimulated with LPS, conversely, the administration of B. uniformis CECT 7771 increased TNF-α production and phagocytosis. Administering this strain also increased TNF-α production by dendritic cells (DCs in response to LPS stimulation, which was significantly reduced by HFD. B. uniformis CECT 7771 also restored the capacity of DCs to induce a T-cell proliferation response, which was impaired in obese mice. HFD induced marked changes in gut microbiota composition, which were partially restored by the intervention. CONCLUSIONS: Altogether, the findings indicate that administration of B. uniformis CECT 7771 ameliorates HFD

  20. Structure of the GH76 α-mannanase homolog, BT2949, from the gut symbiont Bacteroides thetaiotaomicron

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Andrew J. [University of York, Heslington, York YO10 5DD (United Kingdom); Cuskin, Fiona [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Spears, Richard J.; Dabin, Jerome; Turkenburg, Johan P. [University of York, Heslington, York YO10 5DD (United Kingdom); Gilbert, Harry J., E-mail: harry.gilbert@newcastle.ac.uk [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Davies, Gideon J., E-mail: harry.gilbert@newcastle.ac.uk [University of York, Heslington, York YO10 5DD (United Kingdom)

    2015-02-01

    A high-resolution structure of a noncanonical α-mannanase relevant to human health and nutrition has been solved via heavy-atom phasing of a selenomethionine derivative. The large bowel microbiota, a complex ecosystem resident within the gastrointestinal tract of all human beings and large mammals, functions as an essential, nonsomatic metabolic organ, hydrolysing complex dietary polysaccharides and modulating the host immune system to adequately tolerate ingested antigens. A significant member of this community, Bacteroides thetaiotaomicron, has evolved a complex system for sensing and processing a wide variety of natural glycoproducts in such a way as to provide maximum benefit to itself, the wider microbial community and the host. The immense ability of B. thetaiotaomicron as a ‘glycan specialist’ resides in its enormous array of carbohydrate-active enzymes, many of which are arranged into polysaccharide-utilization loci (PULs) that are able to degrade sugar polymers that are often inaccessible to other gut residents, notably α-mannan. The B. thetaiotaomicron genome encodes ten putative α-mannanases spread across various PULs; however, little is known about the activity of these enzymes or the wider implications of α-mannan metabolism for the health of both the microbiota and the host. In this study, SAD phasing of a selenomethionine derivative has been used to investigate the structure of one such B. thetaiotaomicron enzyme, BT2949, which belongs to the GH76 family of α-mannanases. BT2949 presents a classical (α/α){sub 6}-barrel structure comprising a large extended surface cleft common to other GH76 family members. Analysis of the structure in conjunction with sequence alignments reveals the likely location of the catalytic active site of this noncanonical GH76.

  1. Pglyrp-Regulated Gut Microflora Prevotella falsenii, Parabacteroides distasonis and Bacteroides eggerthii Enhance and Alistipes finegoldii Attenuates Colitis in Mice.

    Science.gov (United States)

    Dziarski, Roman; Park, Shin Yong; Kashyap, Des Raj; Dowd, Scot E; Gupta, Dipika

    2016-01-01

    Dysbiosis is a hallmark of inflammatory bowel disease (IBD), but it is unclear which specific intestinal bacteria predispose to and which protect from IBD and how they are regulated. Peptidoglycan recognition proteins (Pglyrps) are antibacterial, participate in maintaining intestinal microflora, and modulate inflammatory responses. Mice deficient in any one of the four Pglyrp genes are more sensitive to dextran sulfate sodium (DSS)-induced colitis, and stools from Pglyrp-deficient mice transferred to wild type (WT) germ-free mice predispose them to much more severe colitis than stools from WT mice. However, the identities of these Pglyrp-regulated bacteria that predispose Pglyrp-deficient mice to colitis or protect WT mice from colitis are not known. Here we identified significant changes in β-diversity of stool bacteria in Pglyrp-deficient mice compared with WT mice. The most consistent changes in microbiome in all Pglyrp-deficient mice were in Bacteroidales, from which we selected four species, two with increased abundance (Prevotella falsenii and Parabacteroides distasonis) and two with decreased abundance (Bacteroides eggerthii and Alistipes finegoldii). We then gavaged WT mice with stock type strains of these species to test the hypothesis that they predispose to or protect from DSS-induced colitis. P. falsenii, P. distasonis, and B. eggerthii all enhanced DSS-induced colitis in both WT mice with otherwise undisturbed intestinal microflora and in WT mice with antibiotic-depleted intestinal microflora. By contrast, A. finegoldii (which is the most abundant species in WT mice) attenuated DSS-induced colitis both in WT mice with otherwise undisturbed intestinal microflora and in WT mice with antibiotic-depleted intestinal microflora, similar to the colitis protective effect of the entire normal microflora. These results identify P. falsenii, P. distasonis, and B. eggerthii as colitis-promoting species and A. finegoldii as colitis-protective species.

  2. Antianaerobe activity of ceftobiprole, a new broad-spectrum cephalosporin.

    Science.gov (United States)

    Ednie, Lois; Shapiro, Stuart; Appelbaum, Peter C

    2007-05-01

    Agar dilution testing of 463 anaerobes showed most Gram-positive beta-lactamase-negative strains (other than some Clostridium difficile and Peptostreptococcus anaerobius), as well as both beta-lactamase-positive and beta-lactamase-negative strains of Fusobacterium nucleatum, to have ceftobiprole MIC values of Ceftobiprole was less active against beta-lactamase-positive Gram-negative bacilli, especially the members of the Bacteroides fragilis group. Like ceftobiprole, piperacillin was active mainly against beta-lactamase-negative strains, though MIC values for piperacillin were often 1 to 2 dilutions higher than for ceftobiprole. Carbapenems had MIC values < or =4 microg/L against all except some C. difficile and 2 strains of B. fragilis. All strains were susceptible to metronidazole, and all bacteria, except C. difficile and a single Bacteroides distasonis strain, were susceptible to chloramphenicol. Clindamycin resistance was seen in most anaerobe groups, whereas high moxifloxacin MICs were found mainly among the B. fragilis and Prevotella groups, and a few C. difficile and F. nucleatum strains.

  3. Trichoderma harzianum Rifai 1295-22 mediates growth promotion of crack willow (Salix fragilis) saplings in both clean and metal-contaminated soil.

    Science.gov (United States)

    Adams, P; De-Leij, F A A M; Lynch, J M

    2007-08-01

    We investigated if the plant growth promoting fungus Trichoderma harzianum Rifai 1295-22 (also known as "T22") could be used to enhance the establishment and growth of crack willow (Salix fragilis) in a soil containing no organic or metal pollutants and in a metal-contaminated soil by comparing this fungus with noninoculated controls and an ectomycorrhizal formulation commercially used to enhance the establishment of tree saplings. Crack willow saplings were grown in a temperature-controlled growth room over a period of 5 weeks' in a garden center topsoil and over 12 weeks in a soil which had been used for disposal of building materials and sewage sludge containing elevated levels of heavy metals including cadmium (30 mg kg(-1)), lead (350 mg kg(-1)), manganese (210 mg kg(-1)), nickel (210 mg kg(-1)), and zinc (1,100 mg kg(-1)). After 5 weeks' growth in clean soil, saplings grown with T. harzianum T22 produced shoots and roots that were 40% longer than those of the controls and shoots that were 20% longer than those of saplings grown with ectomycorrhiza (ECM). T. harzianum T22 saplings produced more than double the dry biomass of controls and more than 50% extra biomass than the ECM-treated saplings. After 12 weeks' growth, saplings grown with T. harzianum T22 in the metal-contaminated soil produced 39% more dry weight biomass and were 16% taller than the noninoculated controls. This is the first report of tree growth stimulation by application of Trichoderma to roots, and is especially important as willow is a major source of wood fuel in the quest for renewable energy. These results also suggest willow trees inoculated with T. harzianum T22 could be used to increase the rate of revegetation and phytostabilization of metal-contaminated sites, a property of the fungus never previously demonstrated.

  4. Infection with bacteroides thetaiotaomicron during posterior decompression and dynamic stabilization of the lumbar spine: a case report and review of the literature.

    Science.gov (United States)

    Agarwal, Nitin; Hansberry, David R; Goldstein, Ira M

    2014-08-01

    Patient and surgical risk factors have often been implicated for postoperative posterior spinal wound infection. A 56-year-old male with widely disseminated multiple myeloma presented with severe back pain and lower extremity weakness as a result of fracture and collapse of the L4 vertebral body. Posterior decompression involving bilateral pedicle resection and partial L4 corpectomy was performed. Stabilization was performed by Dynesys instrumentation of L3-5, screw supplementation with polymethylmethacrylate, and posterolateral fusion was performed. Postoperatively, the patient suffered from multiple infections, including Bacteroides thetaiotaomicron, which were eventually resolved with antibiotic as well as incision and debridement treatment regimens. In cases with numerous perioperative risk factors for infections, the best therapeutic approach may be a preventative one. An understanding of the relevant risk factors may enable the physician to facilitate a perioperative condition best suited for optimal treatment. A case report of infection with Bacteroides thetaiotaomicron during lumbar decompression and dynamic stabilization as well as a review of the literature regarding infection risk factors are presented.

  5. A Highly Active Endo-Levanase BT1760 of a Dominant Mammalian Gut Commensal Bacteroides thetaiotaomicron Cleaves Not Only Various Bacterial Levans, but Also Levan of Timothy Grass

    Science.gov (United States)

    Vija, Heiki; Aasamets, Anneli; Viigand, Katrin

    2017-01-01

    Bacteroides thetaiotaomicron, an abundant commensal of the human gut, degrades numerous complex carbohydrates. Recently, it was reported to grow on a β-2,6-linked polyfructan levan produced by Zymomonas mobilis degrading the polymer into fructooligosaccharides (FOS) with a cell surface bound endo-levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3 of Pseudomonas syringae pv. tomato, its mutant Asp300Asn, levansucrases of Zymomonas mobilis, Erwinia herbicola, Halomonas smyrnensis as well as on levan isolated from timothy grass. For the first time a plant levan is shown as a perfect substrate for an endo-fructanase of a human gut bacterium. BT1760 degraded levans to FOS with degree of polymerization from 2 to 13. At optimal reaction conditions up to 1 g of FOS were produced per 1 mg of BT1760 protein. Low molecular weight (prebiotic fiber for B. thetaiotaomicron and contribute to short-chain fatty acids synthesis by gut microbiota. In the genome of Bacteroides xylanisolvens of human origin a putative levan degradation locus was disclosed. PMID:28103254

  6. Scientific Opinion on the safety of ‘heat-treated milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food

    DEFF Research Database (Denmark)

    Tetens, Inge

    Following a request from the European Commission, the EFSA NDA Panel was asked to carry out the additional assessment for ‘pasteurised milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food (NF) in the context of Regulation (EC) No 258/97. Pasteurised or ultra-high-temp......Following a request from the European Commission, the EFSA NDA Panel was asked to carry out the additional assessment for ‘pasteurised milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food (NF) in the context of Regulation (EC) No 258/97. Pasteurised or ultra......-high-temperature-treated milk is used for the fermentation process with B. xylanisolvens DSM 23964. After fermentation the product is heat treated for one hour at 75 °C to ensure the absence of viable B. xylanisolvens DSM 23964. The Panel considers the information provided on the identity and characterisation of B....... xylanisolvens DSM 23964 to be sufficient. The production process encompasses standard techniques used by the dairy industry, is sufficiently described by the applicant and does not give rise to safety concerns. The Panel considers that the information provided on the production process and on the content...

  7. Effects of selected non-digestible dietary carbohydrates on the composition of the large intestinal microbiota and susceptibility to salmonella infections

    DEFF Research Database (Denmark)

    Petersen, Anne

    in the faecal microbiota including an increase in the Bacteroidetes phylum, the Bacteroides fragilis group and in Bifidobacterium spp., while reductions were observed in the Firmicutes phylum and the Clostridium coccoides group. The findings thus suggest that some microbial changes in the large intestine may...... in the C. coccoides group. Other microbial changes observed, including a reduction in Bifidobacterium spp. and sulphate-reducing bacteria, suggest that quantities of some bacterial species are related to changes in faecal water genotoxicity. Conclusively, the studies contribute to our knowledge...

  8. [Tracing the Fecal Contamination Sources Based on Bacteroides 16S rRNA PCR- DGGE in Karst Groundwater: Taking Laolongdong Underground River System, Nanshan, Chongqing as an Example].

    Science.gov (United States)

    Zhang, Hong; Jiang, Yong-jun; Zhang, Yuan-zhu; Duan, Yi-fan; Lü, Xian-fu; He, Qiu-fang

    2016-05-15

    Microbial contamination in karst groundwater continually increases and tracing the source researches has become a hot topic for international researchers. In this study, Laolongdong underground river at Nanshan, Chongqing was chosen as an example to adopt filter membrane methods to monitor the fecal microbial contaminations including the total bacterial concentration (TB), the total E. coli concentration (TE), the total fecal coliform (FC) and the total fecal Streptocoocci (FS). Bacteriodes was used as an indicator and PCR-DGGE analysis was used to trace fecal contamination sources in karst groundwater. The results suggested that groundwater in this area was seriously polluted by microbes from feces. The concentrations of microbial parameters exceeded limited levels greatly and the total bacterial amounts ranged 10-2.9 x 10⁷ CFU · mL⁻¹, the concentrations of E. coli were between 4.3-4.0 x 10⁵ CFU · mL⁻¹, the max concentration of FC was 1.1 x 10⁶ CFU · (100 mL)⁻¹ and the max concentration of FS was 1.1 x 10⁵ CFU · (100 mL)⁻¹. The FC/FS ratios were mostly over 2 which suggested that the main fecal source in groundwater was human feces. In addition, PCR-DGGE contrastive analysis of Bacteroides communities showed that the similarities between groundwater samples and human feces were in range of 7. 1% -69. 1% , and the similarity of the groundwater sample from Laolongdong underground river outlet was 69.1% . Bacteroides community similarities between groundwater samples and swine feces were in range of 1.1%-53.4%, and the similarity of Laolongdong underground river outlet was merely 1.5%. The similarity data implied that groundwater contamination resulted mainly from human feces, swine feces contamination composed part of animals' fecal contamination, and other animals' feces participated too. Furthermore, sequencing results of PCR-DGGE products revealed that most Bacteroides in groundwater originated from human intestinal tract and human feces.

  9. Molecular analysis of the carbapenem and metronidazole resistance mechanisms of Bacteroides strains reported in a Europe-wide antibiotic resistance survey.

    Science.gov (United States)

    Sóki, József; Eitel, Zsuzsa; Urbán, Edit; Nagy, Elisabeth

    2013-02-01

    Here we examine the carbapenem and metronidazole resistance mechanisms of 640 Bacteroides strains reported in the 2008-2009 European antibiotic susceptibility survey. Of the 22 strains with elevated imipenem minimum inhibitory concentrations (≥4 μg/mL), 10 were cfiA-positive and out of these 5 carried activating insertion sequence (IS) elements in the upstream regions of the cfiA genes. However, resistant strains with cfiA genes but with no activating IS elements were found (n=2) as well as a resistant strain with no cfiA gene. In the former the resistance phenotypes by Etest were heterogeneous, whilst in the latter no carbapenemase production was seen; both mechanisms have been rarely observed, examined and characterised. Interestingly, few (n=3) nim-positive strains were found, including one metronidazole-resistant strain harbouring nimE activated by ISBf6, and two susceptible strains harbouring chromosomally located nim genes.

  10. Characterization of the first alginolytic operons in a marine bacterium: from their emergence in marine Flavobacteriia to their independent transfers to marine Proteobacteria and human gut Bacteroides.

    Science.gov (United States)

    Thomas, François; Barbeyron, Tristan; Tonon, Thierry; Génicot, Sabine; Czjzek, Mirjam; Michel, Gurvan

    2012-09-01

    Alginate constitutes a significant part of seaweed biomass and thus a crucial nutrient for numerous marine heterotrophic bacteria. However, the mechanisms for alginate assimilation remain largely unknown in marine microorganisms. We show here that the genome of the marine flavobacterium Zobellia galactanivorans contains seven putative alginate lyase genes, five of them localized within two clusters comprising additional carbohydrate-related genes. The transcription of these genes and the alginolytic activity were strongly induced when Z. galactanivorans used alginate as sole carbon source. These clusters were shown to be transcribed as polycistronic mRNAs and thus to constitute operons. Several candidate enzymes were successfully overexpressed in Escherichia coli, purified and their activity tested. Particularly, AlyA1, AlyA4, AlyA5 and AlyA7 are confirmed as active alginate lyases. Zg2622 and Zg2614 are a dehydrogenase and a kinase, respectively, further converting the terminal unsaturated monosaccharides released by alginate lyases into 2-keto-3-deoxy-6-phosphogluconate. In-depth phylogenomic analyses reveal that such alginolytic operons originated from an ancestral marine flavobacterium and were independently transferred to marine proteobacteria and Japanese gut Bacteroides. These bacteria thus gained the capacity to assimilate the main polysaccharide of brown algae, an adaptive advantage in coastal environments but also in the gut microbiota of specific human population.

  11. Scientific Opinion on the safety of ?heat-treated milk products fermented with Bacteroides xylanisolvens DSM 23964? as a novel food

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA

    2015-01-01

    Full Text Available Following a request from the European Commission, the EFSA NDA Panel was asked to carry out the additional assessment for ‘pasteurised milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food (NF in the context of Regulation (EC No 258/97. Pasteurised or ultra-high-temperature-treated milk is used for the fermentation process with B. xylanisolvens DSM 23964. After fermentation the product is heat treated for one hour at 75 °C to ensure the absence of viable B. xylanisolvens DSM 23964. The Panel considers the information provided on the identity and characterisation of B. xylanisolvens DSM 23964 to be sufficient. The production process encompasses standard techniques used by the dairy industry, is sufficiently described by the applicant and does not give rise to safety concerns. The Panel considers that the information provided on the production process and on the content of vitamins B2 and B12 and furosine in heat-treated fermented milk products does not give rise to concerns regarding disadvantageous nutritional effects. The Panel considers that the microbiological data provided do not give rise to safety concerns. The Panel also notes that a pilot study and a RCT over six weeks with 140 volunteers receiving daily doses of a spray-dried heat-treated fermented milk product containing intakes of up to 1 ´ 1012 inactivated bacterial cells of B. xylanisolvens DSM 23964 were provided. No clinical effects related to the treatment were observed in the two studies. Although no information has been provided to conclude on the risk of allergic reactions caused by the NF, the Panel considers that it is unlikely that its allergenic potential is dissimilar to that of other fermented dairy products. The Panel concludes that the NF ‘heat-treated milk products fermented with B. xylanisolvens DSM 23964’ is safe for the proposed uses and at the proposed use levels.

  12. Effects of Diet on Resource Utilization by a Model Human Gut Microbiota Containing Bacteroides cellulosilyticus WH2, a Symbiont with an Extensive Glycobiome

    Energy Technology Data Exchange (ETDEWEB)

    McNulty, Nathan [Washington University, St. Louis; Wu, Meng [Washington University, St. Louis; Erickson, Alison L [ORNL; Pan, Chongle [ORNL; Erickson, Brian K [ORNL; Martens, Eric C [University of Michigan; Pudlo, Nicholas A [University of Michigan; Muegge, Brian [Washington University, St. Louis; Henrissat, Bernard [Universite d' Aix-Marseille I & II; Hettich, Robert {Bob} L [ORNL; Gordon, Jeffrey [Washington University, St. Louis

    2013-01-01

    The human gut microbiota is an important metabolic organ, yet little is known about how its individual species interact, establish dominant positions, and respond to changes in environmental factors such as diet. In this study, gnotobiotic mice were colonized with an artificial microbiota comprising 12 sequenced human gut bacterial species and fed oscillating diets of disparate composition. Rapid, reproducible, and reversible changes in the structure of this assemblage were observed. Time-series microbial RNA-Seq analyses revealed staggered functional responses to diet shifts throughout the assemblage that were heavily focused on carbohydrate and amino acid metabolism. High-resolution shotgun metaproteomics confirmed many of these responses at a protein level. One member, Bacteroides cellulosilyticus WH2, proved exceptionally fit regardless of diet. Its genome encoded more carbohydrate active enzymes than any previously sequenced member of the Bacteroidetes. Transcriptional profiling indicated that B. cellulosilyticus WH2 is an adaptive forager that tailors its versatile carbohydrate utilization strategy to available dietary polysaccharides, with a strong emphasis on plant-derived xylans abundant in dietary staples like cereal grains. Two highly expressed, diet-specific polysaccharide utilization loci (PULs) in B. cellulosilyticus WH2 were identified, one with characteristics of xylan utilization systems. Introduction of a B. cellulosilyticus WH2 library comprising .90,000 isogenic transposon mutants into gnotobiotic mice, along with the other artificial community members, confirmed that these loci represent critical diet-specific fitness determinants. Carbohydrates that trigger dramatic increases in expression of these two loci and many of the organism s 111 other predicted PULs were identified by RNA-Seq during in vitro growth on 31 distinct carbohydrate substrates, allowing us to better interpret in vivo RNA-Seq and proteomics data. These results offer insight

  13. Development of Bacteroides 16S rRNA Gene TaqMan-Based Real-Time PCR Assays for Estimation of Total, Human, and Bovine Fecal Pollution in Water

    Science.gov (United States)

    Layton, Alice; McKay, Larry; Williams, Dan; Garrett, Victoria; Gentry, Randall; Sayler, Gary

    2006-01-01

    Bacteroides species are promising indicators for differentiating livestock and human fecal contamination in water because of their high concentration in feces and potential host specificity. In this study, a real-time PCR assay was designed to target Bacteroides species (AllBac) present in human, cattle, and equine feces. Direct PCR amplification (without DNA extraction) using the AllBac assay was tested on feces diluted in water. Fecal concentrations and threshold cycle were linearly correlated, indicating that the AllBac assay can be used to estimate the total amount of fecal contamination in water. Real-time PCR assays were also designed for bovine-associated (BoBac) and human-associated (HuBac) Bacteroides 16S rRNA genes. Assay specificities were tested using human, bovine, swine, canine, and equine fecal samples. The BoBac assay was specific for bovine fecal samples (100% true-positive identification; 0% false-positive identification). The HuBac assay had a 100% true-positive identification, but it also had a 32% false-positive rate with potential for cross-amplification with swine feces. The assays were tested using creek water samples from three different watersheds. Creek water did not inhibit PCR, and results from the AllBac assay were correlated with those from Escherichia coli concentrations (r2 = 0.85). The percentage of feces attributable to bovine and human sources was determined for each sample by comparing the values obtained from the BoBac and HuBac assays with that from the AllBac assay. These results suggest that real-time PCR assays without DNA extraction can be used to quantify fecal concentrations and provide preliminary fecal source identification in watersheds. PMID:16751534

  14. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  15. Group morphology

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.

    2000-01-01

    In its original form, mathematical morphology is a theory of binary image transformations which are invariant under the group of Euclidean translations. This paper surveys and extends constructions of morphological operators which are invariant under a more general group TT, such as the motion group

  16. Group devaluation and group identification

    NARCIS (Netherlands)

    Leach, C.W.; Rodriguez Mosquera, P.M.; Vliek, M.L.W.; Hirt, E.

    2010-01-01

    In three studies, we showed that increased in-group identification after (perceived or actual) group devaluation is an assertion of a (preexisting) positive social identity that counters the negative social identity implied in societal devaluation. Two studies with real-world groups used order manip

  17. The gut microbial community in metabolic syndrome patients is modified by diet.

    Science.gov (United States)

    Haro, Carmen; Garcia-Carpintero, Sonia; Alcala-Diaz, Juan F; Gomez-Delgado, Francisco; Delgado-Lista, Javier; Perez-Martinez, Pablo; Rangel Zuñiga, Oriol A; Quintana-Navarro, Gracia M; Landa, Blanca B; Clemente, Jose C; Lopez-Miranda, Jose; Camargo, Antonio; Perez-Jimenez, Francisco

    2016-01-01

    Intestinal microbiota changes may be involved in the development of metabolic syndrome (MetS), which is a multicomponent disorder frequently associated with obesity. The aim of this study was to test the effect of consuming two healthy diets: a Mediterranean diet and a low-fat high-carbohydrate diet, for 2years in the gut microbiota of MetS patients and those in the control group. We analyzed the differences in the bacterial community structure between the groups after 2years of dietary intervention (Mediterranean or low-fat diet) through quantitative polymerase chain reaction using primers, targeting specific bacterial taxa. We observed, at basal time, that the abundance of Bacteroides, Eubacterium and Lactobacillus genera is lower in the control group than in MetS patients, while Bacteroides fragilis group, Parabacteroides distasonis, Bacteroides thetaiotaomicron, Faecalibacterium prausnitzii, Fusobacterium nucleatum, Bifidobacterium longum, Bifidobacterium adolescentis, Ruminococcus flavefaciens subgroup and Eubacterium rectale are depleted in MetS patients (all P values diet partially restores the population of P. distasonis, B. thetaiotaomicron, F. prausnitzii, B. adolescentis and B. longum in MetS patients (all P values diet could be a useful tool to restore potentially beneficial members of the gut microbiota, although the stability of these changes over time still remains to be assessed.

  18. Gut Dysbiosis in Patients with Anorexia Nervosa.

    Science.gov (United States)

    Morita, Chihiro; Tsuji, Hirokazu; Hata, Tomokazu; Gondo, Motoharu; Takakura, Shu; Kawai, Keisuke; Yoshihara, Kazufumi; Ogata, Kiyohito; Nomoto, Koji; Miyazaki, Kouji; Sudo, Nobuyuki

    2015-01-01

    Anorexia nervosa (AN) is a psychological illness with devastating physical consequences; however, its pathophysiological mechanism remains unclear. Because numerous reports have indicated the importance of gut microbiota in the regulation of weight gain, it is reasonable to speculate that AN patients might have a microbial imbalance, i.e. dysbiosis, in their gut. In this study, we compared the fecal microbiota of female patients with AN (n = 25), including restrictive (ANR, n = 14) and binge-eating (ANBP, n = 11) subtypes, with those of age-matched healthy female controls (n = 21) using the Yakult Intestinal Flora-SCAN based on 16S or 23S rRNA-targeted RT-quantitative PCR technology. AN patients had significantly lower amounts of total bacteria and obligate anaerobes including those from the Clostridium coccoides group, Clostridium leptum subgroup, and Bacteroides fragilis group than the age-matched healthy women. Lower numbers of Streptococcus were also found in the AN group than in the control group. In the analysis based on AN subtypes, the counts of the Bacteroides fragilis group in the ANR and ANBP groups and the counts of the Clostridium coccoides group in the ANR group were significantly lower than those in the control group. The detection rate of the Lactobacillus plantarum subgroup was significantly lower in the AN group than in the control group. The AN group had significantly lower acetic and propionic acid concentrations in the feces than the control group. Moreover, the subtype analysis showed that the fecal concentrations of acetic acid were lower in the ANR group than in the control group. Principal component analysis confirmed a clear difference in the bacterial components between the AN patients and healthy women. Collectively, these results clearly indicate the existence of dysbiosis in the gut of AN patients.

  19. Gut Dysbiosis in Patients with Anorexia Nervosa.

    Directory of Open Access Journals (Sweden)

    Chihiro Morita

    Full Text Available Anorexia nervosa (AN is a psychological illness with devastating physical consequences; however, its pathophysiological mechanism remains unclear. Because numerous reports have indicated the importance of gut microbiota in the regulation of weight gain, it is reasonable to speculate that AN patients might have a microbial imbalance, i.e. dysbiosis, in their gut. In this study, we compared the fecal microbiota of female patients with AN (n = 25, including restrictive (ANR, n = 14 and binge-eating (ANBP, n = 11 subtypes, with those of age-matched healthy female controls (n = 21 using the Yakult Intestinal Flora-SCAN based on 16S or 23S rRNA-targeted RT-quantitative PCR technology. AN patients had significantly lower amounts of total bacteria and obligate anaerobes including those from the Clostridium coccoides group, Clostridium leptum subgroup, and Bacteroides fragilis group than the age-matched healthy women. Lower numbers of Streptococcus were also found in the AN group than in the control group. In the analysis based on AN subtypes, the counts of the Bacteroides fragilis group in the ANR and ANBP groups and the counts of the Clostridium coccoides group in the ANR group were significantly lower than those in the control group. The detection rate of the Lactobacillus plantarum subgroup was significantly lower in the AN group than in the control group. The AN group had significantly lower acetic and propionic acid concentrations in the feces than the control group. Moreover, the subtype analysis showed that the fecal concentrations of acetic acid were lower in the ANR group than in the control group. Principal component analysis confirmed a clear difference in the bacterial components between the AN patients and healthy women. Collectively, these results clearly indicate the existence of dysbiosis in the gut of AN patients.

  20. Group Grammar

    Science.gov (United States)

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  1. MUYANG GROUP

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ With its headquarters in the historic city of Yangzhou,Jiangsu Muyang Group Co.,Ltd has since its founding in 1967 grown into a well-known group corporation whose activities cover research&development.project design,manufacturing,installation and services in a multitude of industries including feed machinery and engineering,storage engineering,grain machinery and engineering,environmental protection,conveying equipment and automatic control systems.

  2. Abelian groups

    CERN Document Server

    Fuchs, László

    2015-01-01

    Written by one of the subject’s foremost experts, this book focuses on the central developments and modern methods of the advanced theory of abelian groups, while remaining accessible, as an introduction and reference, to the non-specialist. It provides a coherent source for results scattered throughout the research literature with lots of new proofs. The presentation highlights major trends that have radically changed the modern character of the subject, in particular, the use of homological methods in the structure theory of various classes of abelian groups, and the use of advanced set-theoretical methods in the study of undecidability problems. The treatment of the latter trend includes Shelah’s seminal work on the undecidability in ZFC of Whitehead’s Problem; while the treatment of the former trend includes an extensive (but non-exhaustive) study of p-groups, torsion-free groups, mixed groups, and important classes of groups arising from ring theory. To prepare the reader to tackle these topics, th...

  3. A metapopulation of the lizard Anguis fragilis (Squamata: Anguidae on a local scale in Dorset, Great Britain, as indicated by spatial distribution and movement

    Directory of Open Access Journals (Sweden)

    Thomas Haley

    2014-12-01

    Full Text Available A metapopulation is a group of spatially structured populations, consisting of distinct units (subpopulations that are separated by space or barriers, and connected by dispersal movements. Evidence derived from Gaussian finite-mixture models and dispersal events suggests that slow-worms may exist in a metapopulation. The Gaussian finite-mixture models showed that slow-worms are aggregated into individual subpopulations; the movement data revealed that males are more likely to migrate than females and that they have the ability to travel sufficiently far to bridge subpopulations. Therefore, the evidence supports the metapopulation theory and that slow-worms exist in multiple small subpopulations instead of one large homogenous population.

  4. Algebraic Groups

    DEFF Research Database (Denmark)

    2007-01-01

    of algebraic groups (in a broad sense) has seen important developments in several directions, also related to representation theory and algebraic geometry. The workshop aimed at presenting some of these developments in order to make them accessible to a "general audience" of algebraic group......-theorists, and to stimulate contacts between participants. Each of the first four days was dedicated to one area of research that has recently seen decisive progress: \\begin{itemize} \\item structure and classification of wonderful varieties, \\item finite reductive groups and character sheaves, \\item quantum cohomology...... of homogeneous varieties, \\item representation categories and their connections to orbits and flag varieties. \\end{itemize} The first three days started with survey talks that will help to make the subject accessible to the next generation. The talks on the last day introduced to several recent advances...

  5. Group Anonymity

    CERN Document Server

    Chertov, Oleg; 10.1007/978-3-642-14058-7_61

    2010-01-01

    In recent years the amount of digital data in the world has risen immensely. But, the more information exists, the greater is the possibility of its unwanted disclosure. Thus, the data privacy protection has become a pressing problem of the present time. The task of individual privacy-preserving is being thoroughly studied nowadays. At the same time, the problem of statistical disclosure control for collective (or group) data is still open. In this paper we propose an effective and relatively simple (wavelet-based) way to provide group anonymity in collective data. We also provide a real-life example to illustrate the method.

  6. Influence of Bifidobacterium longum BB536 intake on faecal microbiota in individuals with Japanese cedar pollinosis during the pollen season.

    Science.gov (United States)

    Odamaki, Toshitaka; Xiao, Jin-Zhong; Iwabuchi, Noriyuki; Sakamoto, Mitsuo; Takahashi, Noritoshi; Kondo, Shizuki; Miyaji, Kazuhiro; Iwatsuki, Keiji; Togashi, Hideo; Enomoto, Tadao; Benno, Yoshimi

    2007-10-01

    It has been reported that intake of yogurt or powder supplemented with the Bifidobacterium longum BB536 probiotic strain alleviated subjective symptoms and affected blood markers of allergy in individuals with Japanese cedar pollinosis (JCPsis) during the pollen seasons of 2004 and 2005, based on randomized, double-blind, placebo-controlled trials. Furthermore, the 2004 study found that intestinal bacteria such as the Bacteroides fragilis group significantly fluctuated during the pollen season in JCPsis individuals and intake of BB536 yogurt tended to suppress these fluctuations. The present study investigated faecal microbiota to examine whether any changes occurred during the pollen season and whether any influence was exerted by intake of BB536 powder in the 2005 pollen season, which happened to be a heavy season, to confirm the 2004 findings and to evaluate the relationship of microbiota with symptom development. In a randomized, double-blind, placebo-controlled trial, 44 JCPsis subjects received BB536 or a placebo for 13 weeks during the pollen season. Another 14 Japanese cedar pollen (JCP)-specific IgE negative healthy subjects received placebo for the same period. Faecal samples were collected before (week 0), during (weeks 4, 8 and 13) and after (week 17) intervention, and out of JCP season (week 28). Faecal microbiota were analysed using terminal-RFLP (T-RFLP) and real-time PCR methods. Principal component analysis based on T-RFLP indicated distinct patterns of microbiota between healthy subjects and JCPsis subjects in the placebo group, but an intermediate pattern in the BB536 group at week 13, the last stage of the pollen season. The coordinate of principal component 1 at week 13 correlated with composite scores of JCPsis symptoms recorded during the pollen season. Faecalibacterium prausnitzii and the Bacteroides fragilis group were identified as the main contributors to microbiotal fluctuations. Real-time PCR indicated that BB536 intake suppressed

  7. Informal groups

    NARCIS (Netherlands)

    E. van den Berg; P. van Houwelingen; J. de Hart

    2011-01-01

    Original title: Informele groepen Going out running with a group of friends, rather than joining an official sports club. Individuals who decide to take action themselves rather than giving money to good causes. Maintaining contact with others not as a member of an association, but through an Inter

  8. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group, established at the start of 2010, has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure There are now 55 CMS Centres worldwide that are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS offline and computing operations, hosting dedicated analysis efforts such as during the CMS Heavy Ion lead-lead running. With a majority of CMS sub-detectors now operating in a “shifterless” mode, many monitoring operations are now routinely performed from there, rather than in the main Control Room at P5. The CMS Communications Group, CERN IT and the EVO team are providing excellent videoconferencing support for the rapidly-increasing number of CMS meetings. In parallel, CERN IT and ...

  9. Group play

    DEFF Research Database (Denmark)

    Tychsen, Anders; Hitchens, Michael; Brolund, Thea

    2008-01-01

    of group dynamics, the influence of the fictional game characters and the comparative play experience between the two formats. The results indicate that group dynamics and the relationship between the players and their digital characters, are integral to the quality of the gaming experience in multiplayer......Role-playing games (RPGs) are a well-known game form, existing in a number of formats, including tabletop, live action, and various digital forms. Despite their popularity, empirical studies of these games are relatively rare. In particular there have been few examinations of the effects...... of the various formats used by RPGs on the gaming experience. This article presents the results of an empirical study, examining how multi-player tabletop RPGs are affected as they are ported to the digital medium. Issues examined include the use of disposition assessments to predict play experience, the effect...

  10. Lego Group

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Pedersen, Torben; Slepniov, Dmitrij

    2010-01-01

    The last years’ rather adventurous journey from 2004 to 2009 had taught the fifth-largest toy-maker in the world - the LEGO Group - the importance of managing the global supply chain effectively. In order to survive the largest internal financial crisis in its roughly 70 years of existence......, the management had, among many initiatives, decided to offshore and outsource a major chunk of its production to Flextronics. In this pursuit of rapid cost-cutting sourcing advantages, the LEGO Group planned to license out as much as 80 per cent of its production besides closing down major parts...... of the production in high cost countries. Confident with the prospects of the new partnership, the company signed a long-term contract with Flextronics. This decision eventually proved itself to have been too hasty, however. Merely three years after the contracts were signed, LEGO management announced that it would...

  11. Group Connections: Whole Group Teaching.

    Science.gov (United States)

    Griffiths, Dorothy

    2002-01-01

    A learner-centered approach to adult group instruction involved learners in investigating 20th-century events. The approach allowed learners to concentrate on different activities according to their abilities and gave them opportunities to develop basic skills and practice teamwork. (SK)

  12. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The CMS Communications Group, established at the start of 2010, has been strengthening the activities in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The Communications Group has invested a lot of effort to support the operations needs of CMS. Hence, the CMS Centres where physicists work on remote CMS shifts, Data Quality Monitoring, and Data Analysis are running very smoothly. There are now 55 CMS Centres worldwide, up from just 16 at the start of CMS data-taking. The latest to join are Imperial College London, the University of Iowa, and the Università di Napoli. The CMS Centre@CERN in Meyrin, which is now full repaired after the major flooding at the beginning of the year, has been at the centre of CMS offline and computing operations, most recently hosting a large fraction of the CMS Heavy Ion community during the lead-lead run. A number of sub-detector shifts can now take pla...

  13. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS Offline and Computing operations, and a number of subdetector shifts can now take place there, rather than in the main Control Room at P5. A new CMS meeting room has been equipped for videoconferencing in building 42, next to building 40. Our building 28 meeting room and the facilities at P5 will be refurbished soon and plans are underway to steadily upgrade the ageing equipment in all 15 CMS meeting rooms at CERN. The CMS evaluation of the Vidyo tool indicates that it is not yet ready to be considered as a potential replacement for EVO. The Communications Group provides the CMS-TV (web) cha...

  14. Studies on the pathogenicity of anaerobes, especially Prevotella bivia, in a rat pyometra model.

    Science.gov (United States)

    Mikamo, H; Kawazoe, K; Izumi, K; Watanabe, K; Ueno, K; Tamaya, T

    1998-01-01

    OBJECTIVE: Prevotella bivia is one of the anaerobic bacteria that resides in the flora of the female genital tract. We studied the pathogenicity of P. bivia in a rat pyometra model. METHODS: The experimental animal (rat) model of pyometra was developed to investigate the pathogenicity of P. bivia in a rat pyometra model. RESULTS: In the groups inoculated with aerobes alone, the infection rate was 10% (1/10) in the Staphylococcus aureus- or Staphylococcus agalactiae-inoculated group and 20% (2/10) in the Escherichia coli-inoculated group. Infection was not established in the groups inoculated with anaerobes alone. High infection rates were observed in all the mixed-infection groups. In the S. agalactiae- and Bacteroides fragilis-, S. agalactiae- and P. bivia-, F. coli- and B. fragilis-, and E. coli- and P. bivia-inoculated groups, an infection rate of 100% (10/10) was demonstrated. The efficacy of antibiotics such as flomoxef (FMOX) could be determined using a rat pyometra model. In relation to the alteration of vaginal microbial flora during the menstrual cycle, estrogen increased the growth of P. bivia. CONCLUSION: Mixture of aerobic bacteria and P. bivia increased the pathogenicity of P. bivia. Estrogen would be useful for raising up the inflammatory change of the uterus in experimental models of genital tract infection due to P. bivia. PMID:9702587

  15. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2012-01-01

      Outreach and Education We are fortunate that our research has captured the public imagination, even though this inevitably puts us under the global media spotlight, as we saw with the Higgs seminar at CERN in December, which had 110,000 distinct webcast viewers. The media interest was huge with 71 media organisations registering to come to CERN to cover the Higgs seminar, which was followed by a press briefing with the DG and Spokespersons. This event resulted in about 2,000 generally positive stories in the global media. For this seminar, the CMS Communications Group prepared up-to-date news and public material, including links to the CMS results, animations and event displays [http://cern.ch/go/Ch8thttp://cern.ch/go/Ch8t]. There were 44,000 page-views on the CMS public website, with the Higgs news article being by far the most popular item. CMS event displays from iSpy are fast becoming the iconic media images, featuring on numerous major news outlets (BBC, CNN, MSN...) as well as in the sci...

  16. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The recently established CMS Communications Group, led by Lucas Taylor, has been busy in all three of its main are areas of responsibility: Communications Infrastructure, Information Systems, and Outreach and Education Communications Infrastructure The damage caused by the flooding of the CMS Centre@CERN on 21st December has been completely repaired and all systems are back in operation. Major repairs were made to the roofs, ceilings and one third of the floor had to be completely replaced. Throughout these works, the CMS Centre was kept operating and even hosted a major press event for first 7 TeV collisions, as described below. Incremental work behind the scenes is steadily improving the quality of the CMS communications infrastructure, particularly Webcasting, video conferencing, and meeting rooms at CERN. CERN/IT is also deploying a pilot service of a new videoconference tool called Vidyo, to assess whether it might provide an enhanced service at a lower cost, compared to the EVO tool currently in w...

  17. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin is particularly busy at the moment, hosting about 50 physicists taking part in the heavy-ion data-taking and analysis. Three new CMS meeting room will be equipped for videoconferencing in early 2012: 40/5B-08, 42/R-031, and 28/S-029. The CMS-TV service showing LHC Page 1, CMS Page 1, etc. (http://cmsdoc.cern.ch/cmscc/projector/index.jsp) is now also available for mobile devices: http://cern.ch/mcmstv. Figure 12: Screenshots of CMS-TV for mobile devices Information Systems CMS has a new web site: (http://cern.ch/cms) using a modern web Content Management System to ensure content and links are managed and updated easily and coherently. It covers all CMS sub-projects and groups, replacing the iCMS internal pages. It also incorporates the existing CMS public web site (http:/...

  18. THE PCR DETECTION AND CLINIC SIGNIFICANCE ABOUT BACTEROIDES FORSYTHUS IN THE PATIENTS WITH PERI-IMPLANTITIS%种植体周围袋中福赛类杆菌的PCR检测及临床意义

    Institute of Scientific and Technical Information of China (English)

    王海涛; 隋素琴; 白燕; 张晓敏; 杨慧; 曹庆堂

    2012-01-01

    Objective: we can provide the basis for evaluation in peri - implantitis diagnosis and treatment through exploring the peri - implant pathogenesis and analysing the distribution prevalance and content of Bacteroides forsythus (B. f) in peri - implantitis patients . chronic periodontitis patients and periodontally healthy adults. Method: Subgingival plaque samples were collected from 56 peri -implantitis patients,60 chronic periodontitis patients and 58 periodontally healthy adults. Bacteroides forsythus were detected by 16S rRNA polymerase chain reaction. Results:The prevalance of B. f differed significantly in patients with peri - implantitis, patients with chronic periodontitis and periodontally healthy adults( P 0.05). Ct of B. f in peri - im-plantitis is higher than chronic periodontitis (P <0.05). Conclusion: These results indicate a possible association between chronical periodontal disease,chronical peri -implantitis disease and content of B. f, Implant denture need more special maintenance.%目的:探讨福赛类杆菌在牙周健康者龈沟液中、慢性牙周炎病人牙周袋内、种植体周围炎病人种植周围袋内的含量及其与感染发生的关系.方法:收集58名牙周健康者、60例慢性牙周炎病人、56例慢性种植体周围炎病人龈下菌斑,采用免疫荧光定量16S RNA PCR方法检测福赛类杆菌的含量与分布.结果 牙周健康者龈沟内福赛类杆菌的检出率为8.62%,平均Ct值为0.0122±0.0000;慢性牙周炎病人龈下菌斑福赛类杆菌的检出率为81.67%,平均Ct值为0.0356±0.0018;慢性种植体周围炎病人龈下菌斑赛类杆菌的检出率为85.71%,平均Ct值为0.0563±0.0021.结论:种植体周围炎、慢性牙周炎的发生与福赛类杆菌的感染有相关性,种植体周围炎、慢性牙周炎的发病机理可能相一致.

  19. 肉桂水提物对大鼠肠道梭菌属IV簇细菌和拟杆菌的影响%Effect of aqueous Cinnamomum cassia extracts on gastrointestinal Clostridium cluster IV and Bacteroides in rats

    Institute of Scientific and Technical Information of China (English)

    黄丽珠; 詹宏林; 王聪; 彭喜春; 张宁; 刘柳

    2012-01-01

    目的:肉桂水提物对大鼠结肠和直肠梭菌属IV簇和拟杆菌的影响。方法:给SD大鼠灌胃一个月后分别取结肠和直肠内容物,针对肠道梭菌属IV簇和拟杆菌的16SrRNA基因应用末端限制性片段多态性分析技术对这两类菌的多样性及分布进行分析。结果:研究发现肉桂水提物能降低梭菌属IV簇细菌在结肠和直肠中的数量,增加拟杆菌属细菌在结肠和直肠中的数量;该水提物对结肠和直肠的结构均产生影响,但影响并不相同,其中对直肠的影响更大。结论:肉桂水提物对大鼠肠道菌群的这种影响可能与肉桂治疗肥胖和糖尿病有功效有关。%Objective:To explore the impact of aqueous Cinnamomum cassia(C.cassia) extracts on gut microbiota.Methods:The colon and rectal contents were sampled after rats had been orally administrated the aqueous extracts for one month.Clostridium cluster IV and Bacteroides in the samples were analyzed by the terminal restriction fragment length polymorphism(tRFLP) method based on the bacterial 16S rRNA gene and nucleotide sequencing.Result:The aqueous C.cassia extracts could down-regulate the amount of microbiota of Clostridium cluster IV in rat gut,along with the increase of microbiota of Bacteroides.Various effects were exerted by the extracts on microbiota in colon and rectum,and the impact presented heavier in rectum.Conclusion:These variations of rat gut microbiota induced by the aqueous C.cassia extracts may reflect the functions of anti-obese and anti-dyspepsia of C.cassia.

  20. From mapping class groups to automorphism groups of free groups

    DEFF Research Database (Denmark)

    Wahl, Nathalie

    2005-01-01

    We show that the natural map from the mapping class groups of surfaces to the automorphism groups of free groups, induces an infinite loop map on the classifying spaces of the stable groups after plus construction. The proof uses automorphisms of free groups with boundaries which play the role...... of mapping class groups of surfaces with several boundary components....

  1. Experimental peritonitis in horses: peritoneal fluid composition Peritonite experimental em eqüinos: composição do líquido peritoneal

    Directory of Open Access Journals (Sweden)

    L.C.N. Mendes

    1999-06-01

    Full Text Available Sixteen adult horses were randomly divided into four equal groups of four animals and each group was injected intraperitoneally with one of the following suspension: Group I, 100×10(7 colony-forming units (CFU of E. coli diluted in 500ml of 0.9% saline; Group II, 100×10(7 CFU of Bacteroides fragilis in 500ml of 0.9% saline; Group III, 100×10(7 CFU of E. coli in combination with 100×10(7 CFU of B. fragilis in 500ml of 0.9% saline; Group IV, 500ml of 0.9% saline. A significant increase in leukocyte number was observed in the peritoneal fluid by four hours after the inoculations in animals of Group I and II, and by eight hours in animals of Group III. The highest cell count observed was 516×10³ leukocytes/mm³. Significant increases in peritoneal fluid fibrinogen (1g/dl and total protein (9.1% concentrations were also observed. Horses inoculated with pure cultures of either E. coli or B. fragilis demonstrated mild and self-limiting peritonitis, while those inoculated with a combination of both bacteria demonstrated laboratory findings of higher intensity and duration.Dezesseis eqüinos adultos foram aleatoriamente divididos em quatro grupos de quatro animais que receberam inoculação intraperitoneal das seguintes suspenções: grupo I, 100×10(7 unidades formadoras de colônias (CFU de E. coli diluídas em 500ml de solução salina a 0,9%; grupo II, 100×10(7 CFU de Bacteroides fragilis em 500ml de solução salina a 0,9%; grupo III, 100×10(7 CFU de E. coli combinados com 100×10(7 CFU de B. fragilis em 500ml de solução salina a 0,9%; grupo IV, 500ml de solução salina a 0,9%. Observou-se aumento significativo do número de leucócitos no líquido peritoneal quatro horas após as inoculações dos animais dos grupos I e II, e oito horas após as inoculações dos animais do grupo III. A contagem mais elevada foi de 516×10³ leucócitos/mm³. Aumentos significativos nas concentrações de fibrinogênio (1g/dl e proteína total (9

  2. Tissue-associated bacterial alterations in rectal carcinoma patients revealed by 16S rRNA community profiling

    Directory of Open Access Journals (Sweden)

    Andrew Maltez Thomas

    2016-12-01

    Full Text Available Sporadic and inflammatory forms of colorectal cancer (CRC account for more than 80% of cases. Recent publications have shown mechanistic evidence for the involvement of gut bacteria in the development of both CRC-forms. Whereas colon and rectal cancer have been routinely studied together as CRC, increasing evidence show these to be distinct diseases. Also, the common use of fecal samples to study microbial communities may reflect disease state but possibly not the tumor microenvironment. We performed this study to evaluate differences in bacterial communities found in tissue samples of 18 rectal-cancer subjects when compared to 18 non-cancer controls. Samples were collected during exploratory colonoscopy (non-cancer group or during surgery for tumor excision (rectal-cancer group. High throughput 16S rRNA amplicon sequencing of the V4-V5 region was conducted on the Ion PGM platform, reads were filtered using Qiime and clustered using UPARSE. We observed significant increases in species richness and diversity in rectal cancer samples, evidenced by the total number of OTUs and the Shannon and Simpson indexes. Enterotyping analysis divided our cohort into two groups, with the majority of rectal cancer samples clustering into one enterotype, characterized by a greater abundance of Bacteroides and Dorea. At the phylum level, rectal-cancer samples had increased abundance of candidate phylum OD1 (also known as Parcubacteria whilst non-cancer samples had increased abundance of Planctomycetes. At the genera level, rectal-cancer samples had higher abundances of Bacteroides, Phascolarctobacterium, Parabacteroides, Desulfovibrio and Odoribacter whereas non-cancer samples had higher abundances of Pseudomonas, Escherichia, Acinetobacter, Lactobacillus and Bacillus. Two Bacteroides fragilis OTUs were more abundant among rectal-cancer patients seen through 16S rRNA amplicon sequencing, whose presence was confirmed by immunohistochemistry and enrichment verified

  3. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    Science.gov (United States)

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

  4. GenBank blastx search result: AK104703 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104703 001-037-D02 AF129406.1 Bacteroides fragilis alkyl hydroperoxide reductase subunit C (ahp...C) and alkyl hydroperoxide reductase subunit F (ahpF) genes, complete cds.|BCT BCT 8e-36 +3 ...

  5. GenBank blastx search result: AK104317 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104317 001-024-C03 AF129406.1 Bacteroides fragilis alkyl hydroperoxide reductase subunit C (ahp...C) and alkyl hydroperoxide reductase subunit F (ahpF) genes, complete cds.|BCT BCT 8e-19 +3 ...

  6. GenBank blastx search result: AK058859 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058859 001-005-E08 AF129406.1 Bacteroides fragilis alkyl hydroperoxide reductase subunit C (ahp...C) and alkyl hydroperoxide reductase subunit F (ahpF) genes, complete cds.|BCT BCT 4e-11 +1 ...

  7. Pomegranate ellagitannins stimulate growth of gut bacteria in vitro: Implications for prebiotic and metabolic effects.

    Science.gov (United States)

    Li, Zhaoping; Summanen, Paula H; Komoriya, Tomoe; Henning, Susanne M; Lee, Ru-Po; Carlson, Eliisa; Heber, David; Finegold, Sydney M

    2015-08-01

    The present study investigated the effect of pomegranate extract (POMx) and pomegranate juice (POM juice) on the growth of major groups of intestinal bacteria: Enterobacteriaceae, Bacteroides fragilis group, clostridia, bifidobacteria, and lactobacilli, and the utilization of pomegranate polyphenols by Bifidobacterium and Lactobacillus. The total phenolic content of the pomegranate extract and juice was determined using the Folin-Ciocalteau colorimetric method and reported as gallic acid equivalent (GAE). The polyphenol composition was determined by HPLC. Stool specimens were incubated with 400, 100, and 25 μg/ml GAE POMx and POM juice and subjected to selective culture. Bifidobacterium and Lactobacillus strains were incubated with 400 μg/ml GAE POMx and POM juice and metabolites were analyzed. POMx and POM juice increased the mean counts of Bifidobacterium and Lactobacillus and significantly inhibited the growth of B. fragilis group, clostridia, and Enterobacteriaceae in a dose-response manner. Bifidobacterium and Lactobacillus utilized ellagic acid and glycosyl ellagic acid but little or no punicalin was utilized. Neither POMx nor POM juice was converted to urolithins by the test bacteria or the in vitro stool cultures. The effect of pomegranate on the gut bacteria considered to be beneficial (Bifidobacterium and Lactobacillus) suggests that pomegranate may potentially work as a prebiotic. The concept that polyphenols such as those in pomegranate impact gut microbiota populations may establish a new role for polyphenols in human health.

  8. [Postoperative necrotizing fasciitis: a rare and fatal complication].

    Science.gov (United States)

    Ghezala, Hassen Ben; Feriani, Najla

    2016-01-01

    Postoperative parietal complications can be exceptionally severe and serious threatening vital prognosis. Necrotizing fasciitis is a rare infection of the skin and deep subcutaneous tissues, spreading along fascia and adipose tissue. It is mainly caused by group A streptococcus (streptococcus pyogenes) but also by other bacteria such as Vibrio vulnificus, Clostridium perfringens or Bacteroides fragilis. Necrotizing fasciitis is a real surgical and medical emergency. We report, in this study, a very rare case of abdominal parietal gangrene occurring in a 75-year-old woman on the fifth day after surgery for an ovarian cyst. Evolution was marked by occurrence of a refractory septic shock with a rapidly fatal course on the third day of management.

  9. Normal luminal bacteria, especially Bacteroides species, mediate chronic colitis, gastritis, and arthritis in HLA-B27/human beta2 microglobulin transgenic rats.

    OpenAIRE

    Rath, H. C.; Herfarth, H H; Ikeda, J S; Grenther, W B; Hamm, T. E.; Balish, E.; Taurog, J D; Hammer, R. E.; Wilson, K. H.; Sartor, R B

    1996-01-01

    Genetic and environmental factors are important in the pathogenesis of clinical and experimental chronic intestinal inflammation. We investigated the influence of normal luminal bacteria and several groups of selected bacterial strains on spontaneous gastrointestinal and systemic inflammation in HLA-B27 transgenic rats. Rats maintained germfree for 3-9 mo were compared with littermates conventionalized with specific pathogen-free bacteria. Subsequently, germfree transgenic rats were colonized...

  10. Integrated Groups and Smooth Distribution Groups

    Institute of Scientific and Technical Information of China (English)

    Pedro J. MIANA

    2007-01-01

    In this paper, we prove directly that α-times integrated groups define algebra homo-morphisms. We also give a theorem of equivalence between smooth distribution groups and α-times integrated groups.

  11. Group typicality, group loyalty and cognitive development.

    Science.gov (United States)

    Patterson, Meagan M

    2014-09-01

    Over the course of childhood, children's thinking about social groups changes in a variety of ways. Developmental Subjective Group Dynamics (DSGD) theory emphasizes children's understanding of the importance of conforming to group norms. Abrams et al.'s study, which uses DSGD theory as a framework, demonstrates the social cognitive skills underlying young elementary school children's thinking about group norms. Future research on children's thinking about groups and group norms should explore additional elements of this topic, including aspects of typicality beyond loyalty.

  12. Which finite simple groups are unit groups?

    DEFF Research Database (Denmark)

    Davis, Christopher James; Occhipinti, Tommy

    2014-01-01

    We prove that if G is a finite simple group which is the unit group of a ring, then G is isomorphic to either (a) a cyclic group of order 2; (b) a cyclic group of prime order 2^k −1 for some k; or (c) a projective special linear group PSLn(F2) for some n ≥ 3. Moreover, these groups do all occur a...

  13. Group Cohesion in Experiential Growth Groups

    Science.gov (United States)

    Steen, Sam; Vasserman-Stokes, Elaina; Vannatta, Rachel

    2014-01-01

    This article explores the effect of web-based journaling on changes in group cohesion within experiential growth groups. Master's students were divided into 2 groups. Both used a web-based platform to journal after each session; however, only 1 of the groups was able to read each other's journals. Quantitative data collected before and…

  14. Group Work Publication-1991.

    Science.gov (United States)

    Zimpfer, David G.

    1992-01-01

    Lists 21 new publications in group work, of which 9 are reviewed. Those discussed include publications on group counseling and psychotherapy, structured groups, support groups, psychodrama, and social group work. (Author/NB)

  15. Group theories: relevance to group safety studies.

    Science.gov (United States)

    Benevento, A L

    1998-01-01

    Promoting safety in the workplace has been attempted in a variety of ways. Increasingly, industries are using groups such as safety teams and quality circles to promote worker safety. Group influences on individual behavior and attitudes have long been studied in the social psychology literature, but the theories have not been commonly found outside the psychology arena. This paper describes the group theories of group polarization, risky shift, social loafing, groupthink and team think and attempts to apply these theories to existing studies that examine work group influences on safety. Interesting parallels were found but only one study examined group influences as their primary focus of research. Since groups are increasingly used for safety promotion, future research on safety that studies group influences with respect to current group theories is recommended.

  16. Interagency mechanical operations group numerical systems group

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    This report consists of the minutes of the May 20-21, 1971 meeting of the Interagency Mechanical Operations Group (IMOG) Numerical Systems Group. This group looks at issues related to numerical control in the machining industry. Items discussed related to the use of CAD and CAM, EIA standards, data links, and numerical control.

  17. AREVA group overview; Presentation du groupe AREVA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-02-08

    This document presents the Group Areva, a world nuclear industry leader, from a financial holding company to an industrial group, operating in two businesses: the nuclear energy and the components. The structure and the market of the group are discussed, as the financial assets. (A.L.B.)

  18. Introduction to Sporadic Groups

    Directory of Open Access Journals (Sweden)

    Luis J. Boya

    2011-01-01

    Full Text Available This is an introduction to finite simple groups, in particular sporadic groups, intended for physicists. After a short review of group theory, we enumerate the 1+1+16=18 families of finite simple groups, as an introduction to the sporadic groups. These are described next, in three levels of increasing complexity, plus the six isolated ''pariah'' groups. The (old five Mathieu groups make up the first, smallest order level. The seven groups related to the Leech lattice, including the three Conway groups, constitute the second level. The third and highest level contains the Monster group M, plus seven other related groups. Next a brief mention is made of the remaining six pariah groups, thus completing the 5+7+8+6=26 sporadic groups. The review ends up with a brief discussion of a few of physical applications of finite groups in physics, including a couple of recent examples which use sporadic groups.

  19. Tissue-Associated Bacterial Alterations in Rectal Carcinoma Patients Revealed by 16S rRNA Community Profiling

    Science.gov (United States)

    Thomas, Andrew M.; Jesus, Eliane C.; Lopes, Ademar; Aguiar, Samuel; Begnami, Maria D.; Rocha, Rafael M.; Carpinetti, Paola Avelar; Camargo, Anamaria A.; Hoffmann, Christian; Freitas, Helano C.; Silva, Israel T.; Nunes, Diana N.; Setubal, João C.; Dias-Neto, Emmanuel

    2016-01-01

    Sporadic and inflammatory forms of colorectal cancer (CRC) account for more than 80% of cases. Recent publications have shown mechanistic evidence for the involvement of gut bacteria in the development of both CRC-forms. Whereas, colon and rectal cancer have been routinely studied together as CRC, increasing evidence show these to be distinct diseases. Also, the common use of fecal samples to study microbial communities may reflect disease state but possibly not the tumor microenvironment. We performed this study to evaluate differences in bacterial communities found in tissue samples of 18 rectal-cancer subjects when compared to 18 non-cancer controls. Samples were collected during exploratory colonoscopy (non-cancer group) or during surgery for tumor excision (rectal-cancer group). High throughput 16S rRNA amplicon sequencing of the V4–V5 region was conducted on the Ion PGM platform, reads were filtered using Qiime and clustered using UPARSE. We observed significant increases in species richness and diversity in rectal cancer samples, evidenced by the total number of OTUs and the Shannon and Simpson indexes. Enterotyping analysis divided our cohort into two groups, with the majority of rectal cancer samples clustering into one enterotype, characterized by a greater abundance of Bacteroides and Dorea. At the phylum level, rectal-cancer samples had increased abundance of candidate phylum OD1 (also known as Parcubacteria) whilst non-cancer samples had increased abundance of Planctomycetes. At the genera level, rectal-cancer samples had higher abundances of Bacteroides, Phascolarctobacterium, Parabacteroides, Desulfovibrio, and Odoribacter whereas non-cancer samples had higher abundances of Pseudomonas, Escherichia, Acinetobacter, Lactobacillus, and Bacillus. Two Bacteroides fragilis OTUs were more abundant among rectal-cancer patients seen through 16S rRNA amplicon sequencing, whose presence was confirmed by immunohistochemistry and enrichment verified by digital

  20. Interplay between weight loss and gut microbiota composition in overweight adolescents.

    Science.gov (United States)

    Santacruz, Arlette; Marcos, Ascensión; Wärnberg, Julia; Martí, Amelia; Martin-Matillas, Miguel; Campoy, Cristina; Moreno, Luis A; Veiga, Oscar; Redondo-Figuero, Carlos; Garagorri, Jesús M; Azcona, Cristina; Delgado, Manuel; García-Fuentes, Miguel; Collado, Maria C; Sanz, Yolanda

    2009-10-01

    The aim of this study was to determine the influence of an obesity treatment program on the gut microbiota and body weight of overweight adolescents. Thirty-six adolescents (13-15 years), classified as overweight according to the International Obesity Task Force BMI criteria, were submitted to a calorie-restricted diet (10-40%) and increased physical activity (15-23 kcal/kg body weight/week) program over 10 weeks. Gut bacterial groups were analyzed by quantitative real-time PCR before and after the intervention. A group of subjects (n=23) experienced >4.0 kg weight loss and showed significant BMI (P=0.030) and BMI z-score (P=0.035) reductions after the intervention, while the other group (n=13) showed <2.0 kg weight loss. No significant differences in dietary intake were found between both groups. In the whole adolescent population, the intervention led to increased Bacteroides fragilis group (P=0.001) and Lactobacillus group (P=0.030) counts, and to decreased Clostridium coccoides group (P=0.028), Bifidobacterium longum (P=0.031), and Bifidobacterium adolescentis (P=0.044) counts. In the high weight-loss group, B. fragilis group and Lactobacillus group counts also increased (P=0.001 and P=0.007, respectively), whereas C. coccoides group and B. longum counts decreased (P=0.001 and P=0.044, respectively) after the intervention. Total bacteria, B. fragilis group and Clostridium leptum group, and Bifidobacterium catenulatum group counts were significantly higher (P<0.001-0.036) while levels of C. coccoides group, Lactobacillus group, Bifidobacterium, Bifidobacterium breve, and Bifidobacterium bifidum were significantly lower (P<0.001-0.008) in the high weight-loss group than in the low weight-loss group before and after the intervention. These findings indicate that calorie restriction and physical activity have an impact on gut microbiota composition related to body weight loss, which also seem to be influenced by the individual's microbiota.

  1. Free Boolean Topological Groups

    Directory of Open Access Journals (Sweden)

    Ol’ga Sipacheva

    2015-11-01

    Full Text Available Known and new results on free Boolean topological groups are collected. An account of the properties that these groups share with free or free Abelian topological groups and properties specific to free Boolean groups is given. Special emphasis is placed on the application of set-theoretic methods to the study of Boolean topological groups.

  2. Group Work: How to Use Groups Effectively

    Science.gov (United States)

    Burke, Alison

    2011-01-01

    Many students cringe and groan when told that they will need to work in a group. However, group work has been found to be good for students and good for teachers. Employers want college graduates to have developed teamwork skills. Additionally, students who participate in collaborative learning get better grades, are more satisfied with their…

  3. Homomorphisms of quantum groups

    CERN Document Server

    Meyer, Ralf; Woronowicz, Stanisław Lech

    2010-01-01

    We introduce some equivalent notions of homomorphisms between quantum groups that behave well with respect to duality of quantum groups. Our equivalent definitions are based on bicharacters, coactions, and universal quantum groups, respectively.

  4. MSUD Family Support Group

    Science.gov (United States)

    ... Group The MSUD Family Support Group is a non-profit 501 (c)(3) organization for those with MSUD ... Family Support Group is a 501(c)(3) non-profit organization with no paid staff. Funds are needed ...

  5. Effects of low levels of ciprofloxacin on a chemostat model of the human colonic microflora.

    Science.gov (United States)

    Carman, R J; Woodburn, M A

    2001-06-01

    To study the utility of an in vitro model system for assessing the effect of low concentrations of a fluoroquinolone (FQ) drug on the ecology of the human intestinal microflora, chemostats containing human fecal flora were exposed to 0.43, 4.3, and 43microg of ciprofloxacin (CI) per milliliter. Prior to and during drug exposure, we assayed short-chain fatty acids (SCFA), bacterial populations, and the relative levels of susceptibility of these populations to CI and trovafloxacin (TV), a newer related FQ with increased activity against anaerobes. The degree to which CI affected the chemostat ecology was measured statistically by comparing observed data with the corresponding predicted "no effect" level. No changes in total SCFA were observed; only butyrate was significantly higher at the intermediate and high-dose levels. Enterococci counts and the levels of susceptibility to CI among enterococci were also unaffected. Escherichia coli counts decreased in a dose-dependent manner. Susceptibility levels in E. coli followed no interpretable pattern. Bacteroides fragilis group (BfG) counts decreased significantly following exposure to 43 and 4.3microg/mL CI. Ciprofloxacin susceptibility among the BfG in these chemostats was not determined because the BfG counts were too low (less than 30 colonies per plate) when undiluted chemostat samples were plated. However, within 2 days of exposure to 0.43microg/mL CI, the percentage of BfG resistant to 4microg/mL CI increased to over 95%. Before exposure, all BfG were susceptible to both CI (2microg/mL) and TV (0.25microg/mL). All BfG isolated during exposure were resistant to both CI (4microg/mL) and TV (2microg/mL). Resistance selection in the BfG was unexpected as the MIC(90) of CI for B. fragilis is 8microg/mL. Since the average colon flora is about 20% B. fragilis and other bacteroides, CI may impact the human gut flora even at subtherapeutic levels.

  6. Food Groups Recipes

    OpenAIRE

    2012-01-01

    15 pages In 2011, My Plate replaced the Food Pyramid as a visual representation for the USDA Dietary Guidelines. This publication, a group of recipes based on this new division of food groups, reflects the effort of the USDA and other groups to translate science-based research into everyday practice for Americans. Fifteen recipes (3 from each food group) show ways to use foods from each food group. They are complete with basic nutritional analyses and food group amounts.

  7. Locally minimal topological groups

    OpenAIRE

    Außenhofer, Lydia; Chasco, María Jesús; Dikranjan, Dikran; Domínguez, Xabier

    2009-01-01

    A Hausdorff topological group $(G,\\tau)$ is called locally minimal if there exists a neighborhood $U$ of 0 in $\\tau$ such that $U$ fails to be a neighborhood of zero in any Hausdorff group topology on $G$ which is strictly coarser than $\\tau.$ Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all minimal groups. Motivated by the fact that locally compact NSS groups are Lie groups, we study the connection between local minimality and the ...

  8. The correlation between Clostridium-difficile infection and human gut concentrations of Bacteroidetes phylum and clostridial species.

    Science.gov (United States)

    Goldberg, E; Amir, I; Zafran, M; Gophna, U; Samra, Z; Pitlik, S; Bishara, J

    2014-03-01

    We aimed to assess differences in bacterial intensities of Bacteroidetes phylum and different clostridial species in the human intestines with respect to C. difficile infection. Patients with a stool assay for C. difficile toxin were identified via the microbiology laboratory in our institute. Bacterial populations were quantified from stool samples of four groups of patients: Group I-patients with C. difficile associated diarrhea (CDAD); Group II-asymptomatic C. difficile carriers; Group III-patients with non-C. difficile diarrhea; Group IV-patients with no diarrhea and negative stool samples for the C. difficile toxin (control group). Stool was examined for three genes-C. difficile toxin A gene, 16S rRNA gene from Clostridium thermocellum representing other clostridial species, and 16S rRNA gene from Bacteroides fragilis representing the Bacteroidetes phylum. Fifty-nine patients underwent analysis of the stool (CDAD group 14, carriers group 14, non-C. difficile diarrhea group 16, control group 15). C. difficile concentration was highest in the CDAD group, followed by the carriers group. Higher concentrations of both clostridial species and Bacteriodetes were observed in the control and non-C. difficile diarrhea groups compared to the CDAD and carriers groups. We demonstrated an inverse association between infection with C. difficile and the abundance of Bacteroidetes phylum and other clostridial species in human intestines. Studies with larger samples and broader diagnostic procedures are needed in order to better explore and understand this association.

  9. Ordered groups and infinite permutation groups

    CERN Document Server

    1996-01-01

    The subjects of ordered groups and of infinite permutation groups have long en­ joyed a symbiotic relationship. Although the two subjects come from very different sources, they have in certain ways come together, and each has derived considerable benefit from the other. My own personal contact with this interaction began in 1961. I had done Ph. D. work on sequence convergence in totally ordered groups under the direction of Paul Conrad. In the process, I had encountered "pseudo-convergent" sequences in an ordered group G, which are like Cauchy sequences, except that the differences be­ tween terms of large index approach not 0 but a convex subgroup G of G. If G is normal, then such sequences are conveniently described as Cauchy sequences in the quotient ordered group GIG. If G is not normal, of course GIG has no group structure, though it is still a totally ordered set. The best that can be said is that the elements of G permute GIG in an order-preserving fashion. In independent investigations around that t...

  10. Communication in Organizational Groups

    OpenAIRE

    Monica RADU

    2007-01-01

    Organizational group can be defined as some persons between who exist interactive connections (functional, communication, affective, normative type). Classification of these groups can reflect the dimension, type of relationship or type of rules included. Organizational groups and their influence over the individual efficiency and the efficiency of the entire group are interconnected. Spontaneous roles in these groups sustain the structure of the relationship, and the personality of each indi...

  11. Group Psychotherapy in Iceland.

    Science.gov (United States)

    Ívarsson, Ómar

    2015-10-01

    In this overview of group psychotherapy in Iceland, an attempt will be made to describe how it is practiced today, give some glimpses into its earlier history, and clarify seven issues: (1) the standing of group psychotherapy in Iceland, its previous history, and the theoretical orientation of dynamic group therapy in the country; (2) the role of group therapy in the health care system; (3) how training in group therapy is organized; (4) the relationship between group psychotherapy research and clinical practice; (5) which issues/processes can be identified as unique to therapy groups in Iceland; and (6) how important are group-related issues within the social background of the country; and (7) what group work holds for the future.

  12. Toleration, Groups, and Multiculturalism

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    . The chapter relates the different possible meanings of groups toleration to widespread criticisms of multiculturalism for being excessively 'groupist' (e.g. to essentialise or reify groups), to promote group rights over individual rights, or to deny or ignore the internal heterogeneity of groups...... or the multiple identity affiliations of individuals. The chapter suggests that some of these standard criticisms of multiculturalism for being overly tolerant of minority groups, or being so in a way elevating groups over individuals, are less pressing on some understandings of the meaning of 'group......' as an object of policies of multicultural toleration than on others. So the chapter both contributes to the conceptual understanding of toleration and groups and to the normative debates about multiculturalism insofar as these turn on the toleration of groups....

  13. Locally minimal topological groups

    CERN Document Server

    enhofer, Lydia Au\\ss; Dikranjan, Dikran; Domínguez, Xabier

    2009-01-01

    A Hausdorff topological group $(G,\\tau)$ is called locally minimal if there exists a neighborhood $U$ of 0 in $\\tau$ such that $U$ fails to be a neighborhood of zero in any Hausdorff group topology on $G$ which is strictly coarser than $\\tau.$ Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all minimal groups. Motivated by the fact that locally compact NSS groups are Lie groups, we study the connection between local minimality and the NSS property, establishing that under certain conditions, locally minimal NSS groups are metrizable. A symmetric subset of an abelian group containing zero is said to be a GTG set if it generates a group topology in an analogous way as convex and symmetric subsets are unit balls for pseudonorms on a vector space. We consider topological groups which have a neighborhood basis at zero consisting of GTG sets. Examples of these locally GTG groups are: locally pseudo--convex spaces, groups uniformly free from small subgroups (...

  14. Higher arithmetic Chow groups

    CERN Document Server

    Gil, J I Burgos

    2009-01-01

    We give a new construction of higher arithmetic Chow groups for quasi-projective arithmetic varieties over a field. Our definition agrees with the higher arithmetic Chow groups defined by Goncharov for projective arithmetic varieties over a field. These groups are the analogue, in the Arakelov context, of the higher algebraic Chow groups defined by Bloch. The degree zero group agrees with the arithmetic Chow groups of Burgos. Our new construction is shown to be a contravariant functor and is endowed with a product structure, which is commutative and associative.

  15. Group Decision Process Support

    DEFF Research Database (Denmark)

    Gøtze, John; Hijikata, Masao

    1997-01-01

    Introducing the notion of Group Decision Process Support Systems (GDPSS) to traditional decision-support theorists.......Introducing the notion of Group Decision Process Support Systems (GDPSS) to traditional decision-support theorists....

  16. About group digital signatures

    Directory of Open Access Journals (Sweden)

    Adriana Cristina Enache

    2012-09-01

    Full Text Available

    Group signatures try to combine security (no framing, no cheating and privacy(anonymity, unlinkability.A group digital signature is a digital signature with enhanced privacy features that allows members of a given group to anonymously sign messages on behalf of the group, producing a group signature. However, in the case of dispute the identity of the signature's originator can be revealed by a designated entity (group manager. The present paper describes the main concepts about group signatures, along with a brief state of the art and shows a personal cryptographic library implemented in Java that includes two group signatures.

  17. Working with Groups.

    Science.gov (United States)

    Morris, Joan, Ed.

    1984-01-01

    Describes nine Canadian programs for counseling groups of students. Topics include introducing computer-assisted guidance, future challenges for counselors, sociometry, sexuality, parent counseling, reluctant students, shyness, peer groups, education for living, and guidance advisory committees. (JAC)

  18. Group B streptococcus - pregnancy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000511.htm Group B streptococcus - pregnancy To use the sharing features on this page, please enable JavaScript. Group B streptococcus (GBS) is a type of bacteria that ...

  19. Gestalt Interactional Groups

    Science.gov (United States)

    Harman, Robert L.; Franklin, Richard W.

    1975-01-01

    Gestalt therapy in groups is not limited to individual work in the presence of an audience. Describes several ways to involve gestalt groups interactionally. Interactions described focus on learning by doing and discovering, and are noninterpretive. (Author/EJT)

  20. Fast Overlapping Group Lasso

    CERN Document Server

    Liu, Jun

    2010-01-01

    The group Lasso is an extension of the Lasso for feature selection on (predefined) non-overlapping groups of features. The non-overlapping group structure limits its applicability in practice. There have been several recent attempts to study a more general formulation, where groups of features are given, potentially with overlaps between the groups. The resulting optimization is, however, much more challenging to solve due to the group overlaps. In this paper, we consider the efficient optimization of the overlapping group Lasso penalized problem. We reveal several key properties of the proximal operator associated with the overlapping group Lasso, and compute the proximal operator by solving the smooth and convex dual problem, which allows the use of the gradient descent type of algorithms for the optimization. We have performed empirical evaluations using the breast cancer gene expression data set, which consists of 8,141 genes organized into (overlapping) gene sets. Experimental results demonstrate the eff...

  1. Multicultural group work

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    2014-01-01

    Motivation for the activity I use this strategy for forming groups to ensure diverse/multicultural groups that combine a variety of different strengths and resources based on student's academic, disciplinary, linguistic, national, personal and work backgrounds.......Motivation for the activity I use this strategy for forming groups to ensure diverse/multicultural groups that combine a variety of different strengths and resources based on student's academic, disciplinary, linguistic, national, personal and work backgrounds....

  2. Generalized Group Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The concept of generalized group signature scheme will bepresent. Based on the generalized secret sharing scheme proposed by Lin and Ha rn, a non-interactive approach is designed for realizing such generalized group signature scheme. Using the new scheme, the authorized subsets of the group in w hich the group member can cooperate to produce the valid signature for any messa ge can be randomly specified

  3. Characterization of the gut microbiota of Papua New Guineans using reverse transcription quantitative PCR.

    Directory of Open Access Journals (Sweden)

    Andrew R Greenhill

    Full Text Available There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet.

  4. Characterization of the gut microbiota of Papua New Guineans using reverse transcription quantitative PCR.

    Science.gov (United States)

    Greenhill, Andrew R; Tsuji, Hirokazu; Ogata, Kiyohito; Natsuhara, Kazumi; Morita, Ayako; Soli, Kevin; Larkins, Jo-Ann; Tadokoro, Kiyoshi; Odani, Shingo; Baba, Jun; Naito, Yuichi; Tomitsuka, Eriko; Nomoto, Koji; Siba, Peter M; Horwood, Paul F; Umezaki, Masahiro

    2015-01-01

    There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA) revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet.

  5. Groups, combinatorics and geometry

    CERN Document Server

    Ivanov, A A; Saxl, J

    2003-01-01

    Over the past 20 years, the theory of groups in particular simplegroups, finite and algebraic has influenced a number of diverseareas of mathematics. Such areas include topics where groups have beentraditionally applied, such as algebraic combinatorics, finitegeometries, Galois theory and permutation groups, as well as severalmore recent developments.

  6. Asymmetry within social groups

    DEFF Research Database (Denmark)

    Barker, Jessie; Loope, Kevin J.; Reeve, H. Kern

    2016-01-01

    Social animals vary in their ability to compete with group members over shared resources and also vary in their cooperative efforts to produce these resources. Competition among groups can promote within-group cooperation, but many existing models of intergroup cooperation do not explicitly account...

  7. Isotropy in group cohomology

    DEFF Research Database (Denmark)

    Ben David, Nir; Ginosar, Yuval; Meir, Ehud

    2014-01-01

    groups of central type from such quotients, known as Involutive Yang–Baxter groups. Another motivation for the search of normal Lagrangians comes from a non-commutative generalization of Heisenberg liftings that require normality. Although it is true that symplectic forms over finite nilpotent groups...

  8. Higher arithmetic Chow groups

    DEFF Research Database (Denmark)

    Gil, J. I. Burgos; Feliu, Elisenda

    2012-01-01

    We give a new construction of higher arithmetic Chow groups for quasi-projective arithmetic varieties over a field. Our definition agrees with the higher arithmetic Chow groups defined by Goncharov for projective arithmetic varieties over a field. These groups are the analogue, in the Arakelov co...

  9. CHAOTIC GROUP ACTIONS

    Institute of Scientific and Technical Information of China (English)

    ShiEnhui; ZhouLizhen; ZhouYoucheng

    2003-01-01

    It is proved that there is no chaotic group actions on any topological space with free arc.In this paper the chaotic actions of the group like G×F,where F is a finite group,are studied.In particular,under a suitable assumption ,if F is a cyclic group,then the topological space which admits a chaotic action of Z×F must admit a chatotic homeomorphism.A topological space which admits a chaotic group action but admits no chaotic horneomorphism is constructed.

  10. Grouped exposed metal heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J [Bellaire, TX; Coit, William George [Bellaire, TX; Griffin, Peter Terry [Brixham, GB; Hamilton, Paul Taylor [Houston, TX; Hsu, Chia-Fu [Granada Hills, CA; Mason, Stanley Leroy [Allen, TX; Samuel, Allan James [Kular Lumpar, ML; Watkins, Ronnie Wade [Cypress, TX

    2012-07-31

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  11. Grouped exposed metal heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Coit, William George (Bellaire, TX); Griffin, Peter Terry (Brixham, GB); Hamilton, Paul Taylor (Houston, TX); Hsu, Chia-Fu (Granada Hills, CA); Mason, Stanley Leroy (Allen, TX); Samuel, Allan James (Kular Lumpar, MY); Watkins, Ronnie Wade (Cypress, TX)

    2010-11-09

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  12. On -nilpotent abelian groups

    Indian Academy of Sciences (India)

    Mohammad Mehdi Nasrabadi; Ali Gholamian

    2014-11-01

    Let be a group and $A = \\text{Aut}(G)$ be the group of automorphisms of . Then, the element $[g, ] = g^{-1}(g)$ is an autocommutator of $g \\in G$ and $ \\in A$. Hence, for any natural number the -th autocommutator subgroup of is defined as $K_{m}(G)=\\langle [g,_{1},\\ldots,_{m}]|g\\in G,_{1},\\ldots,_{m}\\in A\\rangle$, where $[g, _{1}, _{2},\\ldots, _{m}] = [[g,_{1},\\ldots,_{m−1}], _{m}]$. In this paper, we introduce the new notion of -nilpotent groups and classify all abelian groups which are -nilpotent groups.

  13. Group I intron ribozymes

    DEFF Research Database (Denmark)

    Nielsen, Henrik

    2012-01-01

    Group I intron ribozymes constitute one of the main classes of ribozymes and have been a particularly important model in the discovery of key concepts in RNA biology as well as in the development of new methods. Compared to other ribozyme classes, group I intron ribozymes display considerable......, the intronic products of these pathways have the potential to integrate into targets and to form various types of circular RNA molecules. Thus, group I intron ribozymes and associated elements found within group I introns is a rich source of biological phenomena. This chapter provides a strategy and protocols...... for initial characterization of new group I intron ribozymes....

  14. Group theory I essentials

    CERN Document Server

    Milewski, Emil G

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Group Theory I includes sets and mapping, groupoids and semi-groups, groups, isomorphisms and homomorphisms, cyclic groups, the Sylow theorems, and finite p-groups.

  15. E-groups training

    CERN Multimedia

    HR Department

    2012-01-01

    There will be an e-groups training course on 16 March 2012 which will cover the main e-groups functionalities i.e.: creating and managing e-groups, difference between static and dynamic e-groups, configuring posting restrictions and archives, examples of where e-groups can be used in daily work. Even if you have already worked with e-groups, this may be a good opportunity to learn about the best practices and security related recommendations when using e-groups. You can find more details as well as enrolment form for the training (it’s free) here. The number of places is limited, so enrolling early is recommended.   Technical Training Tel. 72844

  16. Group Psychotherapy in Italy.

    Science.gov (United States)

    Giannone, Francesca; Giordano, Cecilia; Di Blasi, Maria

    2015-10-01

    This article describes the history and the prevailing orientations of group psychotherapy in Italy (psychoanalytically oriented, psychodrama, CBT groups) and particularly group analysis. Provided free of charge by the Italian health system, group psychotherapy is growing, but its expansion is patchy. The main pathways of Italian training in the different group psychotherapy orientations are also presented. Clinical-theoretical elaboration on self development, psychopathology related to group experiences, and the methodological attention paid to objectives and methods in different clinical groups are issues related to group therapy in Italy. Difficulties in the relationship between research and clinical practice are discussed, as well as the empirical research network that tries to bridge the gap between research and clinical work in group psychotherapy. The economic crisis in Italy has led to massive cuts in health care and to an increasing demand for some forms of psychological treatment. For these reasons, and because of its positive cost-benefit ratio, group psychotherapy is now considered an important tool in the national health care system to expand the clinical response to different forms of psychological distress.

  17. Stochastic Lie group integrators

    CERN Document Server

    Malham, Simon J A

    2007-01-01

    We present Lie group integrators for nonlinear stochastic differential equations with non-commutative vector fields whose solution evolves on a smooth finite dimensional manifold. Given a Lie group action that generates transport along the manifold, we pull back the stochastic flow on the manifold to the Lie group via the action, and subsequently pull back the flow to the corresponding Lie algebra via the exponential map. We construct an approximation to the stochastic flow in the Lie algebra via closed operations and then push back to the Lie group and then to the manifold, thus ensuring our approximation lies in the manifold. We call such schemes stochastic Munthe-Kaas methods after their deterministic counterparts. We also present stochastic Lie group integration schemes based on Castell--Gaines methods. These involve using an underlying ordinary differential integrator to approximate the flow generated by a truncated stochastic exponential Lie series. They become stochastic Lie group integrator schemes if...

  18. Blood groups systems

    Directory of Open Access Journals (Sweden)

    Ranadhir Mitra

    2014-01-01

    Full Text Available International Society of Blood Transfusion has recently recognized 33 blood group systems. Apart from ABO and Rhesus system, many other types of antigens have been noticed on the red cell membranes. Blood grouping and cross-matching is one of the few important tests that the anaesthesiologist orders during perioperative period. Hence, a proper understanding of the blood group system, their clinical significance, typing and cross-matching tests, and current perspective are of paramount importance to prevent transfusion-related complications. Nonetheless, the knowledge on blood group system is necessary to approach blood group-linked diseases which are still at the stage of research. This review addresses all these aspects of the blood groups system.

  19. Quantum isometry groups

    CERN Document Server

    Goswami, Debashish

    2016-01-01

    This book offers an up-to-date overview of the recently proposed theory of quantum isometry groups. Written by the founders, it is the first book to present the research on the “quantum isometry group”, highlighting the interaction of noncommutative geometry and quantum groups, which is a noncommutative generalization of the notion of group of isometry of a classical Riemannian manifold. The motivation for this generalization is the importance of isometry groups in both mathematics and physics. The framework consists of Alain Connes’ “noncommutative geometry” and the operator-algebraic theory of “quantum groups”. The authors prove the existence of quantum isometry group for noncommutative manifolds given by spectral triples under mild conditions and discuss a number of methods for computing them. One of the most striking and profound findings is the non-existence of non-classical quantum isometry groups for arbitrary classical connected compact manifolds and, by using this, the authors explicitl...

  20. Group Problem Solving

    CERN Document Server

    Laughlin, Patrick R

    2011-01-01

    Experimental research by social and cognitive psychologists has established that cooperative groups solve a wide range of problems better than individuals. Cooperative problem solving groups of scientific researchers, auditors, financial analysts, air crash investigators, and forensic art experts are increasingly important in our complex and interdependent society. This comprehensive textbook--the first of its kind in decades--presents important theories and experimental research about group problem solving. The book focuses on tasks that have demonstrably correct solutions within mathematical

  1. Definably amenable NIP groups

    OpenAIRE

    Chernikov, Artem; Simon, Pierre

    2015-01-01

    We study definably amenable NIP groups. We develop a theory of generics, showing that various definitions considered previously coincide, and study invariant measures. Applications include: characterization of regular ergodic measures, a proof of the conjecture of Petrykowski connecting existence of bounded orbits with definable amenability in the NIP case, and the Ellis group conjecture of Newelski and Pillay connecting the model-theoretic connected component of an NIP group with the ideal s...

  2. Semisimple Metacyclic Group Algebras

    Indian Academy of Sciences (India)

    Gurmeet K Bakshi; Shalini Gupta; Inder Bir S Passi

    2011-11-01

    Given a group of order $p_1p_2$, where $p_1,p_2$ are primes, and $\\mathbb{F}_q$, a finite field of order coprime to $p_1p_2$, the object of this paper is to compute a complete set of primitive central idempotents of the semisimple group algebra $\\mathbb{F}_q[G]$. As a consequence, we obtain the structure of $\\mathbb{F}_q[G]$ and its group of automorphisms.

  3. Presentations of groups

    CERN Document Server

    Johnson, D L

    1997-01-01

    The aim of this book is to provide an introduction to combinatorial group theory. Any reader who has completed first courses in linear algebra, group theory and ring theory will find this book accessible. The emphasis is on computational techniques but rigorous proofs of all theorems are supplied. This new edition has been revised throughout, including new exercises and an additional chapter on proving that certain groups are infinite.

  4. E-Group Arrangements

    Science.gov (United States)

    Aylesworth, Grant R.

    Group E at Uaxactún has long been considered an ancient Maya observatory in which an observer could see the sun rise along architectural alignments at the solstices and equinoxes. E-Groups named for the architectural complex list identified in Group E at Uaxactún, typically consist of a large radial pyramid on their west side and three temples on a raised platform on their east side.

  5. CLASSIFICATION OF CRIMINAL GROUPS

    Directory of Open Access Journals (Sweden)

    Natalia Romanova

    2013-06-01

    Full Text Available New types of criminal groups are emerging in modern society.  These types have their special criminal subculture. The research objective is to develop new parameters of classification of modern criminal groups, create a new typology of criminal groups and identify some features of their subculture. Research methodology is based on the system approach that includes using the method of analysis of documentary sources (materials of a criminal case, method of conversations with themembers of the criminal group, method of testing the members of the criminal group and method of observation. As a result of the conducted research, we have created a new classification of criminal groups. The first type is a lawful group in its form and criminal according to its content (i.e., its target is criminal enrichment. The second type is a criminal organization which is run by so-called "white-collars" that "remain in the shadow". The third type is traditional criminal groups.  The fourth type is the criminal group, which openly demonstrates its criminal activity.

  6. Explosive Technology Group

    Data.gov (United States)

    Federal Laboratory Consortium — The Explosive Technology Group (ETG) provides diverse technical expertise and an agile, integrated approach to solve complex challenges for all classes of energetic...

  7. CHINA INTERNATIONAL PUBLISHING GROUP

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The China International Publishing Group (CIPG) specializes in international communications. Its operationsencompass reporting, editing, translation, publishing, printing, distribution, and the Internet. It incorporates sevenpublishing companies, five magazines and 19 periodicals, published in over 20 languages. The ChinaInternational Book Trading Corporation, another group facet, distributes all of these to over 180 countries and

  8. Group Work. Research Brief

    Science.gov (United States)

    Walker, Karen

    2010-01-01

    According to Johnson and Johnson, group work helps increase student retention and satisfaction, develops strong oral communication and social skills, as well as higher self-esteem (University of Minnesota, n.d.). Group work, when planned and implemented deliberately and thoughtfully helps students develop cognitive and leadership skills as well as…

  9. Small Group Inquiry.

    Science.gov (United States)

    Koller, Martin M.

    Learning in small groups is a practical way to bring about behavior change. The inquiry learning process is perceived to be the most natural and scientific way of learning. Skills developed include those of problem-solving task analysis, decision-making, value formation and adaptability. The art of small group interaction is developed. Factual…

  10. Democratic Group Work

    Science.gov (United States)

    Laursen, Erik K.; Tate, Thomas F.

    2012-01-01

    For a century, democratic values have called for abandoning coercive approaches and teaching children and youth to be responsible citizens. The authors explore strategies for creating respectful environments and positive group cultures with challenging youth. They offer suggestions to adult group facilitators to support youth in developing…

  11. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  12. Fairness and Ability Grouping.

    Science.gov (United States)

    Strike, Kenneth A.

    1983-01-01

    A recent controversy regarding ability grouping is that it is often perceived as a means whereby racial or class bias can be subtly transformed into mechanisms of discrimination which exhibit the appearance of fairness and objectivity. This article addresses the question of fairness in ability grouping. (CJB)

  13. Automorphism groups of Quandles

    CERN Document Server

    Elhamdadi, M; Restrepo, R

    2010-01-01

    We prove that the automorphism group of the dihedral quandle with n elements is isomorphic to the affine group of the integers mod n, and also obtain the inner automorphism group of this quandle. In [9], automorphism groups of quandles (up to isomorphisms) of order less than or equal to 5 were given. With the help of the software Maple, we compute the inner and automorphism groups of all seventy three quandles of order six listed in the appendix of [4]. Since computations of automorphisms of quandles relates to the problem of classification of quandles, we also describe an algorithm implemented in C for computing all quandles (up to isomorphism) of order less than or equal to nine.

  14. Perceiving persons and groups.

    Science.gov (United States)

    Hamilton, D L; Sherman, S J

    1996-04-01

    This article analyzes the similarities and differences in forming impressions of individuals and in developing conceptions of groups. In both cases, the perceiver develops a mental conception of the target (individual or group) on the basis of available information and uses that information to make judgments about that person or group. However, a review of existing evidence reveals differences in the outcomes of impressions formed of individual and group targets, even when those impressions are based on the very same behavioral information. A model is proposed to account for these differences. The model emphasizes the role of differing expectancies of unity and coherence in individual and group targets, which in turn engage different mechanisms for processing information and making judgments. Implications of the model are discussed.

  15. Supervision and group dynamics

    DEFF Research Database (Denmark)

    Hansen, Søren; Jensen, Lars Peter

    2004-01-01

    as well as at Aalborg University. The first visible result has been participating supervisors telling us that the course has inspired them to try supervising group dynamics in the future. This paper will explore some aspects of supervising group dynamics as well as, how to develop the Aalborg model...... An important aspect of the problem based and project organized study at Aalborg University is the supervision of the project groups. At the basic education (first year) it is stated in the curriculum that part of the supervisors' job is to deal with group dynamics. This is due to the experience...... that many students are having difficulties with practical issues such as collaboration, communication, and project management. Most supervisors either ignore this demand, because they do not find it important or they find it frustrating, because they do not know, how to supervise group dynamics...

  16. Differential interleukin-10 (IL-10) and IL-23 production by human blood monocytes and dendritic cells in response to commensal enteric bacteria.

    Science.gov (United States)

    Manuzak, Jennifer; Dillon, Stephanie; Wilson, Cara

    2012-08-01

    Human peripheral blood contains antigen-presenting cells (APC), including dendritic cells (DC) and monocytes, that may encounter microbes that have translocated from the intestine to the periphery in disease states like HIV-1 infection and inflammatory bowel disease. We investigated the response of DC and monocytes in peripheral blood mononuclear cells (PBMC) to a panel of representative commensal enteric bacteria, including Escherichia coli, Enterococcus sp., and Bacteroides fragilis. All three bacteria induced significant upregulation of the maturation and activation markers CD40 and CD83 on myeloid dendritic cells (mDC) and plasmacytoid dendritic cells (pDC). However, only mDC produced cytokines, including interleukin-10 (IL-10), IL-12p40/70, and tumor necrosis factor alpha (TNF-α), in response to bacterial stimulation. Cytokine profiles in whole PBMC differed depending on the stimulating bacterial species: B. fragilis induced production of IL-23, IL-12p70, and IL-10, whereas E. coli and Enterococcus induced an IL-10-predominant response. mDC and monocyte depletion experiments indicated that these cell types differentially produced IL-10 and IL-23 in response to E. coli and B. fragilis. Bacteroides thetaiotaomicron did not induce levels of IL-23 similar to those of B. fragilis, suggesting that B. fragilis may have unique proinflammatory properties among Bacteroides species. The addition of recombinant human IL-10 to PBMC cultures stimulated with commensal bacteria abrogated the IL-23 response, whereas blocking IL-10 significantly enhanced IL-23 production, suggesting that IL-10 controls the levels of IL-23 produced. These results indicate that blood mDC and monocytes respond differentially to innate stimulation with whole commensal bacteria and that IL-10 may play a role in controlling the proinflammatory response to translocated microbes.

  17. Impedance group summary

    Science.gov (United States)

    Blaskiewicz, M.; Dooling, J.; Dyachkov, M.; Fedotov, A.; Gluckstern, R.; Hahn, H.; Huang, H.; Kurennoy, S.; Linnecar, T.; Shaposhnikova, E.; Stupakov, G.; Toyama, T.; Wang, J. G.; Weng, W. T.; Zhang, S. Y.; Zotter, B.

    1999-12-01

    The impedance working group was charged to reply to the following 8 questions relevant to the design of high-intensity proton machines such as the SNS or the FNAL driver. These questions were first discussed one by one in the whole group, then each ne of them assigned to one member to summarize. On the lst morning these contributions were publicly read, re-discussed and re-written where required—hence they are not the opinion of a particular person, but rather the averaged opinion of all members of the working group. (AIP)

  18. Building Bunk Group Buddies.

    Science.gov (United States)

    Nelson, Denise Cabrero

    2000-01-01

    Describes how camp counselors can foster camaraderie among campers through participative decision making, name games, listening, adventure courses, storytelling, spending time in nature, decorating cabins, avoiding favoritism, setting rules, admitting faults, setting group goals, and praising sincere efforts. (TD)

  19. Homogenous finitary symmetric groups

    Directory of Open Access Journals (Sweden)

    Otto‎. ‎H‎. Kegel

    2015-03-01

    Full Text Available We characterize strictly diagonal type of embeddings of finitary symmetric groups in terms of cardinality and the characteristic. Namely, we prove the following. Let kappa be an infinite cardinal. If G=underseti=1stackrelinftybigcupG i , where G i =FSym(kappan i , (H=underseti=1stackrelinftybigcupH i , where H i =Alt(kappan i , is a group of strictly diagonal type and xi=(p 1 ,p 2 ,ldots is an infinite sequence of primes, then G is isomorphic to the homogenous finitary symmetric group FSym(kappa(xi (H is isomorphic to the homogenous alternating group Alt(kappa(xi , where n 0 =1,n i =p 1 p 2 ldotsp i .

  20. Groups – Additive Notation

    Directory of Open Access Journals (Sweden)

    Coghetto Roland

    2015-06-01

    Full Text Available We translate the articles covering group theory already available in the Mizar Mathematical Library from multiplicative into additive notation. We adapt the works of Wojciech A. Trybulec [41, 42, 43] and Artur Korniłowicz [25].

  1. Homogeneous group, research, institution

    Directory of Open Access Journals (Sweden)

    Francesca Natascia Vasta

    2014-09-01

    Full Text Available The work outlines the complex connection among empiric research, therapeutic programs and host institution. It is considered the current research state in Italy. Italian research field is analyzed and critic data are outlined: lack of results regarding both the therapeutic processes and the effectiveness of eating disorders group analytic treatment. The work investigates on an eating disorders homogeneous group, led into an eating disorder outpatient service. First we present the methodological steps the research is based on including the strong connection among theory and clinical tools. Secondly clinical tools are described and the results commented. Finally, our results suggest the necessity of validating some more specifical hypothesis: verifying the relationship between clinical improvement (sense of exclusion and painful emotions reduction and specific group therapeutic processes; verifying the relationship between depressive feelings, relapses and transition trough a more differentiated groupal field.Keywords: Homogeneous group; Eating disorders; Institutional field; Therapeutic outcome

  2. Language and Group Identity.

    Science.gov (United States)

    Milroy, Leslie

    1982-01-01

    Explores the tension between the manner in which intergroup language differences are used to symbolize group membership and the manner in which they mirror and reinforce social class and power distinctions. (EKN)

  3. Radiation Protection Group

    CERN Multimedia

    2006-01-01

    The Radioactive Waste Section of the Radiation Protection Group wishes to inform you that the Radioactive Waste Treatment Centre will be closed on the afternoon of Tuesday 19 December 2006. Thank-you for your understanding.

  4. Parton Distributions Working Group

    Energy Technology Data Exchange (ETDEWEB)

    de Barbaro, L.; Keller, S. A.; Kuhlmann, S.; Schellman, H.; Tung, W.-K.

    2000-07-20

    This report summarizes the activities of the Parton Distributions Working Group of the QCD and Weak Boson Physics workshop held in preparation for Run II at the Fermilab Tevatron. The main focus of this working group was to investigate the different issues associated with the development of quantitative tools to estimate parton distribution functions uncertainties. In the conclusion, the authors introduce a Manifesto that describes an optimal method for reporting data.

  5. Networks and Small Groups

    OpenAIRE

    Kadushin, Charles

    2005-01-01

    Homans' insights that interaction and sentiment are in a feedback loop that includes clique formation, social ranking and leadership are formalized and derived from a set of limited assumptions and propositions. Freeman's model of groups is used to detect pure informal groups, those that are not consequential upon anything else than sheer hanging around. It produces a system of cliques and rankings based purely on the rates of transitive triads that may include a third who is only weakly conn...

  6. Fuzzy Soft Topological Groups

    Directory of Open Access Journals (Sweden)

    S. Nazmul

    2014-03-01

    Full Text Available Notions of Lowen type fuzzy soft topological space are introduced and some of their properties are established in the present paper. Besides this, a combined structure of a fuzzy soft topological space and a fuzzy soft group, which is termed here as fuzzy soft topological group is introduced. Homomorphic images and preimages are also examined. Finally, some definitions and results on fuzzy soft set are studied.

  7. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  8. N-ary Groups

    CERN Document Server

    Gal'mak, Alexander M

    2011-01-01

    The book "N-ary Groups" (in Russian) consists of two Parts. It is intended on the one hand as an initial introduction to the theory of n-ary groups, and on the other hand it contains the published results by the author on this subject. At present, the theory of n-ary groups developing but slowly from group theory. Nonetheless, ternary and n-ary structures have recently been applied to modern models of elementary particle physics. One of the author's goals in this book is to draw the attention of mathematicians and theoretical physicists to the theory of n-ary groups, to some of its distinguishing features, and to details relevant to its further development and application. Part I: Theorems of Post and Gluskin-Hosszu. 1.1. Classical definitions of n-ary groups. Examples. 1.2. Analogies of identity and inverse elements. 1.3. Equivalent sequences. 1.4. Post's coset theorem. 1.5. Theorem of Gluskin-Hosszu. 1.6. Connection between the Post's coset theorem and theorem of Gluskin-Hosszu. Addition and comments. Part ...

  9. Coordinating Group report

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    In December 1992, western governors and four federal agencies established a Federal Advisory Committee to Develop On-site Innovative Technologies for Environmental Restoration and Waste Management (the DOIT Committee). The purpose of the Committee is to advise the federal government on ways to improve waste cleanup technology development and the cleanup of federal sites in the West. The Committee directed in January 1993 that information be collected from a wide range of potential stakeholders and that innovative technology candidate projects be identified, organized, set in motion, and evaluated to test new partnerships, regulatory approaches, and technologies which will lead to improve site cleanup. Five working groups were organized, one to develop broad project selection and evaluation criteria and four to focus on specific contaminant problems. A Coordinating Group comprised of working group spokesmen and federal and state representatives, was set up to plan and organize the routine functioning of these working groups. The working groups were charged with defining particular contaminant problems; identifying shortcomings in technology development, stakeholder involvement, regulatory review, and commercialization which impede the resolution of these problems; and identifying candidate sites or technologies which could serve as regional innovative demonstration projects to test new approaches to overcome the shortcomings. This report from the Coordinating Group to the DOIT Committee highlights the key findings and opportunities uncovered by these fact-finding working groups. It provides a basis from which recommendations from the DOIT Committee to the federal government can be made. It also includes observations from two public roundtables, one on commercialization and another on regulatory and institutional barriers impeding technology development and cleanup.

  10. Facilities removal working group

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This working group`s first objective is to identify major economic, technical, and regulatory constraints on operator practices and decisions relevant to offshore facilities removal. Then, the group will try to make recommendations as to regulatory and policy adjustments, additional research, or process improvements and/or technological advances, that may be needed to improve the efficiency and effectiveness of the removal process. The working group will focus primarily on issues dealing with Gulf of Mexico platform abandonments. In order to make the working group sessions as productive as possible, the Facilities Removal Working Group will focus on three topics that address a majority of the concerns and/or constraints relevant to facilities removal. The three areas are: (1) Explosive Severing and its Impact on Marine Life, (2) Pile and Conductor Severing, and (3) Deep Water Abandonments This paper will outline the current state of practice in the offshore industry, identifying current regulations and specific issues encountered when addressing each of the three main topics above. The intent of the paper is to highlight potential issues for panel discussion, not to provide a detailed review of all data relevant to the topic. Before each panel discussion, key speakers will review data and information to facilitate development and discussion of the main issues of each topic. Please refer to the attached agenda for the workshop format, key speakers, presentation topics, and panel participants. The goal of the panel discussions is to identify key issues for each of the three topics above. The working group will also make recommendations on how to proceed on these key issues.

  11. Linear algebraic groups

    CERN Document Server

    Springer, T A

    1998-01-01

    "[The first] ten chapters...are an efficient, accessible, and self-contained introduction to affine algebraic groups over an algebraically closed field. The author includes exercises and the book is certainly usable by graduate students as a text or for self-study...the author [has a] student-friendly style… [The following] seven chapters... would also be a good introduction to rationality issues for algebraic groups. A number of results from the literature…appear for the first time in a text." –Mathematical Reviews (Review of the Second Edition) "This book is a completely new version of the first edition. The aim of the old book was to present the theory of linear algebraic groups over an algebraically closed field. Reading that book, many people entered the research field of linear algebraic groups. The present book has a wider scope. Its aim is to treat the theory of linear algebraic groups over arbitrary fields. Again, the author keeps the treatment of prerequisites self-contained. The material of t...

  12. The Multiplication Group of an AG-group

    OpenAIRE

    Shah, Muhammad; Ali, Asif; Ahmad, Imtiaz; Sorge, Volker

    2014-01-01

    We investigate the multiplication group of a special class of quasigroup called AG-group. We prove some interesting results such as: the multiplication group of an AG-group of order n is non-abelian group of order 2n and its left section is an abelian group of order n. The inner mapping group of an AG-group of any order is a cyclic group of order 2.

  13. Illinois Wind Workers Group

    Energy Technology Data Exchange (ETDEWEB)

    David G. Loomis

    2012-05-28

    The Illinois Wind Working Group (IWWG) was founded in 2006 with about 15 members. It has grown to over 200 members today representing all aspects of the wind industry across the State of Illinois. In 2008, the IWWG developed a strategic plan to give direction to the group and its activities. The strategic plan identifies ways to address critical market barriers to the further penetration of wind. The key to addressing these market barriers is public education and outreach. Since Illinois has a restructured electricity market, utilities no longer have a strong control over the addition of new capacity within the state. Instead, market acceptance depends on willing landowners to lease land and willing county officials to site wind farms. Many times these groups are uninformed about the benefits of wind energy and unfamiliar with the process. Therefore, many of the project objectives focus on conferences, forum, databases and research that will allow these stakeholders to make well-educated decisions.

  14. Doing focus group research

    DEFF Research Database (Denmark)

    Lindegaard, Laura Bang

    2014-01-01

    , not as something that pre-exists or goes beyond the situated interaction. This article, however, challenges not only the first, but also the second position and suggests that it is, after all, possible to do committedly ethnomethodological studies of focus group data that demonstrate how members of a focus group......Scholars of ethnomethodologically informed discourse studies are often sceptical of the use of interview data such as focus group data. Some scholars quite simply reject interview data with reference to a general preference for so-called naturally occurring data. Other scholars acknowledge...... of interview interaction, but inadequate as data for studying phenomena that go beyond the phenomenon of interview interaction. Neither of these more and less sceptical positions are, on the face of it, surprising due to the ethnomethodological commitment to study social order as accomplished in situ...

  15. Quantum threshold group signature

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

  16. Transitive conformal holonomy groups

    CERN Document Server

    Alt, Jesse

    2011-01-01

    For $(M,[g])$ a conformal manifold of signature $(p,q)$ and dimension at least three, the conformal holonomy group $\\mathrm{Hol}(M,[g]) \\subset O(p+1,q+1)$ is an invariant induced by the canonical Cartan geometry of $(M,[g])$. We give a description of all possible connected conformal holonomy groups which act transitively on the M\\"obius sphere $S^{p,q}$, the homogeneous model space for conformal structures of signature $(p,q)$. The main part of this description is a list of all such groups which also act irreducibly on $\\R^{p+1,q+1}$. For the rest, we show that they must be compact and act decomposably on $\\R^{p+1,q+1}$, in particular, by known facts about conformal holonomy the conformal class $[g]$ must contain a metric which is locally isometric to a so-called special Einstein product.

  17. Focus group discussions

    CERN Document Server

    Hennink, Monique M

    2014-01-01

    The Understanding Research series focuses on the process of writing up social research. The series is broken down into three categories: Understanding Statistics, Understanding Measurement, and Understanding Qualitative Research. The books provide researchers with guides to understanding, writing, and evaluating social research. Each volume demonstrates how research should be represented, including how to write up the methodology as well as the research findings. Each volume also reviews how to appropriately evaluate published research. Focus Group Discussions addresses the challenges associated with conducting and writing focus group research. It provides detailed guidance on the practical and theoretical considerations in conducting focus group discussions including: designing the discussion guide, recruiting participants, training a field team, moderating techniques and ethical considerations. Monique Hennink describes how a methodology section is read and evaluated by others, such as journal reviewers or ...

  18. Characterization of adherent bacteroidales from intestinal biopsies of children and young adults with inflammatory bowel disease.

    Directory of Open Access Journals (Sweden)

    Naamah L Zitomersky

    Full Text Available There is extensive evidence implicating the intestinal microbiota in inflammatory bowel disease [IBD], but no microbial agent has been identified as a sole causative agent. Bacteroidales are numerically dominant intestinal organisms that associate with the mucosal surface and have properties that both positively and negatively affect the host. To determine precise numbers and species of Bacteroidales adherent to the mucosal surface in IBD patients, we performed a comprehensive culture based analysis of intestinal biopsies from pediatric Crohn's disease [CD], ulcerative colitis [UC], and control subjects. We obtained biopsies from 94 patients and used multiplex PCR or 16S rDNA sequencing of Bacteroidales isolates for species identification. Eighteen different Bacteroidales species were identified in the study group, with up to ten different species per biopsy, a number higher than demonstrated using 16S rRNA gene sequencing methods. Species diversity was decreased in IBD compared to controls and with increasingly inflamed tissue. There were significant differences in predominant Bacteroidales species between biopsies from the three groups and from inflamed and uninflamed sites. Parabacteroides distasonis significantly decreased in inflamed tissue. All 373 Bacteroidales isolates collected in this study grew with mucin as the only utilizable carbon source suggesting this is a non-pathogenic feature of this bacterial order. Bacteroides fragilis isolates with the enterotoxin gene [bft], previously associated with flares of colitis, were not found more often at inflamed colonic sites or within IBD subjects. B. fragilis isolates with the ability to synthesize the immunomodulatory polysaccharide A [PSA], previously shown to be protective in murine models of colitis, were not detected more often from healthy versus inflamed tissue.

  19. GroupFinder

    DEFF Research Database (Denmark)

    Bøgh, Kenneth Sejdenfaden; Skovsgaard, Anders; Jensen, Christian S.

    2013-01-01

    of PoIs relevant to a user's intent has became a problem of automated spatio-textual information retrieval. Over the last several years, substantial research has gone into the invention of functionality and efficient implementations for retrieving nearby PoIs. However, with a couple of exceptions....... Such groups are relevant to users who wish to conveniently explore several options before making a decision such as to purchase a specific product. Specifically, we demonstrate a practical proposal for finding top-k PoI groups in response to a query. We show how problem parameter settings can be mapped...

  20. Group theory and chemistry

    CERN Document Server

    Bishop, David M

    1993-01-01

    Group theoretical principles are an integral part of modern chemistry. Not only do they help account for a wide variety of chemical phenomena, they simplify quantum chemical calculations. Indeed, knowledge of their application to chemical problems is essential for students of chemistry. This complete, self-contained study, written for advanced undergraduate-level and graduate-level chemistry students, clearly and concisely introduces the subject of group theory and demonstrates its application to chemical problems.To assist chemistry students with the mathematics involved, Professor Bishop ha

  1. Homomorphisms between Kaehler groups

    CERN Document Server

    Arapura, Donu

    2009-01-01

    This is partly a survey and partly a research article. Some known results and open problems about Kaehler groups (fundamental groups of compact Kaehler manifolds) are discussed. A new notion of Kaehler homomorphism is introduced. This is a homomorphism induced by a holomorphic map between these types of manifolds. Some obstructions for a homomorphism to be Kaehler are discussed. Among these is the main result on the vanishing of a certain cohomology class associated to such map. This is reduced to the decomposition theorem for perverse sheaves suitably extended to Kaehler orbifolds.

  2. Fourier Analysis on Groups

    CERN Document Server

    Rudin, Walter

    2011-01-01

    In the late 1950s, many of the more refined aspects of Fourier analysis were transferred from their original settings (the unit circle, the integers, the real line) to arbitrary locally compact abelian (LCA) groups. Rudin's book, published in 1962, was the first to give a systematic account of these developments and has come to be regarded as a classic in the field. The basic facts concerning Fourier analysis and the structure of LCA groups are proved in the opening chapters, in order to make the treatment relatively self-contained.

  3. Group Based Interference Alignment

    CERN Document Server

    Ma, Yanjun; Chen, Rui; Yao, Junliang

    2010-01-01

    in $K$-user single-input single-output (SISO) frequency selective fading interference channels, it is shown that the achievable multiplexing gain is almost surely $K/2$ by using interference alignment (IA). However when the signaling dimensions is limited, allocating all the resource to all the users simultaneously is not optimal. According to this problem, a group based interference alignment (GIA) scheme is proposed and a search algorithm is designed to get the group patterns and the resource allocation among them. Analysis results show that our proposed scheme achieves a higher multiplexing gain when the resource is limited.

  4. Upgraded Coal Interest Group

    Energy Technology Data Exchange (ETDEWEB)

    Evan Hughes

    2009-01-08

    The Upgraded Coal Interest Group (UCIG) is an EPRI 'users group' that focuses on clean, low-cost options for coal-based power generation. The UCIG covers topics that involve (1) pre-combustion processes, (2) co-firing systems and fuels, and (3) reburn using coal-derived or biomass-derived fuels. The UCIG mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired.

  5. FAW Group Gorporation

    Institute of Scientific and Technical Information of China (English)

    Yan Feng

    2007-01-01

    @@ As the founder of China's automobile industry, FAW Group Corporation (FAW) has maintained a dominant position in the automotive industry since its founding in 1953 in terms of its total assets, Production capacity, domestic and international sales, market share, and brand recognition.

  6. Group theory in physics

    CERN Document Server

    Cornwell, J F

    1989-01-01

    Recent devopments, particularly in high-energy physics, have projected group theory and symmetry consideration into a central position in theoretical physics. These developments have taken physicists increasingly deeper into the fascinating world of pure mathematics. This work presents important mathematical developments of the last fifteen years in a form that is easy to comprehend and appreciate.

  7. Leukosis/Sarcoma Group

    Science.gov (United States)

    The leukosis/sarcoma (L/S) group of diseases designates a variety of transmissible benign and malignant neoplasms of chickens caused by members that belong to the family Retroviridae. Because the expansion of the literature on this disease, it is no longer feasible to cite all relevant publications ...

  8. Dimensions of Group Interaction

    Science.gov (United States)

    Dawidowicz, Paula

    2008-01-01

    The correlation between positive and negative group interactions and one or another of individuals' attitudes or characteristics--moral development, critical thinking, resilience, and self efficacy--has been examined previously. However, no systemic examination of individuals' development of patterns of these characteristics and those patterns'…

  9. Working Group Report: Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    de Gouvea, A.; Pitts, K.; Scholberg, K.; Zeller, G. P. [et al.

    2013-10-16

    This document represents the response of the Intensity Frontier Neutrino Working Group to the Snowmass charge. We summarize the current status of neutrino physics and identify many exciting future opportunities for studying the properties of neutrinos and for addressing important physics and astrophysics questions with neutrinos.

  10. Grouping Illumination Frameworks

    Science.gov (United States)

    Zdravkovic, Suncica; Economou, Elias; Gilchrist, Alan

    2012-01-01

    According to Koffka (1935), the lightness of a target surface is determined by the relationship between the target and the illumination frame of reference to which it belongs. However, each scene contains numerous illumination frames, and judging each one separately would lead to an enormous amount of computing. Grouping those frames that are in…

  11. Convolution Operators on Groups

    CERN Document Server

    Derighetti, Antoine

    2011-01-01

    This volume is devoted to a systematic study of the Banach algebra of the convolution operators of a locally compact group. Inspired by classical Fourier analysis we consider operators on Lp spaces, arriving at a description of these operators and Lp versions of the theorems of Wiener and Kaplansky-Helson.

  12. With the Radiobiology Group

    CERN Multimedia

    1980-01-01

    The Radiobiology Group carries out experiments to study the effect of radiation on living cells. The photo shows the apparatus for growing broad beans which have been irradiated by 250 GeV protons. The roots are immersed in a tank of running water (CERN Weekly Bulletin 26 January 1981 and Annual Report 1980 p. 160). Karen Panman, Marilena Streit-Bianchi, Roger Paris.

  13. Group B Streptococcus

    Directory of Open Access Journals (Sweden)

    Albert H. Adriaanse

    1995-01-01

    Full Text Available Objective: Group B streptococcus (GBS, Streptococcus agalactiae is an important cause of neonatal sepsis. Prevention is possible by intrapartum screening for maternal GBS carriership and antimicrobial treatment of colonized women with risk factors during labor. The conflicting results of diagnostic performance are reported both for the newly developed rapid GBS antigen tests and Gram's stain.

  14. Abandoning wells working group

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The primary objective of this working group is to identify major technical, regulatory, and environmental issues that are relevant to the abandonment of offshore wellbores. Once the issues have been identified, the working group also has the objective of making recommendations or providing potential solutions for consideration. Areas for process improvement will be identified and {open_quotes}best practices{close_quotes} will be discussed and compared to {open_quotes}minimum standards.{close_quotes} The working group will primarily focus on wellbore abandonment in the Gulf of Mexico. However, workshop participants are encouraged to discuss international issues which may be relevant to wellbore abandonment practices in the Gulf of Mexico. The Abandoning Wells Group has identified several major areas for discussion that have concerns related to both operators and service companies performing wellbore abandonments in the Gulf of Mexico. The following broad topics were selected for the agenda: (1) MMS minimum requirements and state regulations. (2) Co-existence of best practices, new technology, and P & A economics. (3) Liability and environmental issues relating to wellbore abandonment.

  15. The Ombudperson Initiative Group

    CERN Multimedia

    Laura Stewart

    Following many discussions that took place at some of the ATLAS Women's Network lunch gatherings, a few ATLAS women joined forces with similarly concerned CERN staff women to form a small group last Fall to discuss the need for a CERN-wide Ombudsperson. This has since evolved into the Ombudsperson Initiative Group (OIG) currently composed of the following members: Barbro Asman, Stockholm University; Pierre Charrue, CERN AB; Anna Cook, CERN IT; Catherine Delamare, CERN and IT Ombudsperson; Paula Eerola, Lund University; Pauline Gagnon, Indiana University; Eugenia Hatziangeli, CERN AB; Doreen Klem, CERN IT; Bertrand Nicquevert, CERN TS and Laura Stewart, CERN AT. On June 12, members of the OIG met with representatives of Human Resources (HR) and the Equal Opportunity Advisory Panel (EOAP) to discuss the proposal drafted by the OIG. The meeting was very positive. Everybody agreed that the current procedures at CERN applicable in the event of conflict required a thorough review, and that a professionnally trai...

  16. Gravitation Gauge Group

    CERN Document Server

    Ter-Kazarian, G T

    1997-01-01

    Suggested theory involves a drastic revision of a role of local internal symmetries in physical concept of curved geometry. Under the reflection of fields and their dynamics from Minkowski to Riemannian space a standard gauge principle of local internal symmetries is generalized. The gravitation gauge group is proposed, which is generated by hidden local internal symmetries. The developed mechanism enables one to infer Einstein's equation of gravitation, but only with strong difference from Einstein's theory at the vital point of well-defined energy-momentum tensor of gravitational field and conservation laws. The gravitational interaction as well as general distortion of manifold G(2.2.3) with hidden group U(1) was considered.

  17. Group and representation theory

    CERN Document Server

    Vergados, J D

    2017-01-01

    This volume goes beyond the understanding of symmetries and exploits them in the study of the behavior of both classical and quantum physical systems. Thus it is important to study the symmetries described by continuous (Lie) groups of transformations. We then discuss how we get operators that form a Lie algebra. Of particular interest to physics is the representation of the elements of the algebra and the group in terms of matrices and, in particular, the irreducible representations. These representations can be identified with physical observables. This leads to the study of the classical Lie algebras, associated with unitary, unimodular, orthogonal and symplectic transformations. We also discuss some special algebras in some detail. The discussion proceeds along the lines of the Cartan-Weyl theory via the root vectors and root diagrams and, in particular, the Dynkin representation of the roots. Thus the representations are expressed in terms of weights, which are generated by the application of the elemen...

  18. Group Leaders Optimization Algorithm

    CERN Document Server

    Daskin, Anmer

    2010-01-01

    Complexity of global optimization algorithms makes implementation of the algorithms difficult and leads the algorithms to require more computer resources for the optimization process. The ability to explore the whole solution space without increasing the complexity of algorithms has a great importance to not only get reliable results but so also make the implementation of these algorithms more convenient for higher dimensional and complex-real world problems in science and engineering. In this paper, we present a new global optimization algorithm in which the influence of the leaders in social groups is used as an inspiration for the evolutionary technique that is designed into a group architecture similar to the architecture of Cooperative Coevolutionary Algorithms. Therefore, we present the implementation method and the experimental results for the single and multidimensional optimization test problems and a scientific real world problem, the energies and the geometric structures of Lennard-Jones clusters.

  19. Mindfulness for group facilitation

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine; Krohn, Simon

    2014-01-01

    In this paper, we argue that mindfulness techniques can be used for enhancing the outcome of group performance. The word mindfulness has different connotations in the academic literature. Broadly speaking there is ‘mindfulness without meditation’ or ‘Western’ mindfulness which involves active...... thinking and ‘Eastern’ mindfulness which refers to an open, accepting state of mind, as intended with Buddhist-inspired techniques such as meditation. In this paper, we are interested in the latter type of mindfulness and demonstrate how Eastern mindfulness techniques can be used as a tool for facilitation....... A brief introduction to the physiology and philosophy of Eastern mindfulness constitutes the basis for the arguments of the effect of mindfulness techniques. The use of mindfulness techniques for group facilitation is novel as it changes the focus from individuals’ mindfulness practice...

  20. Communication from ST Group

    CERN Multimedia

    TS Department

    2008-01-01

    Please note that owing the preparations for the Open Days, the FM Group will not able to handle specific requests for waste collection from 2nd to 6th of April, nor removal or PC transport requests between the 31 March and 11 April. We kindly ask you to plan the collection of all types of waste and any urgent transport of office furniture or PCs before 31 March. Waste collection requests must be made by contacting FM Support on 77777 or at the e-mail address mailto:Fm.Support@cern.ch; removal of office furniture or PC transport requests must be made using the EDH ‘Transport request’ form (select "Removals" or "PC transport" from the drop-down menu). For any question concerning the sorting of waste, please consult the following web site: http://dechets-waste.web.cern.ch/dechets-waste/ Thank you for your understanding and collaboration. TS/FM Group

  1. Combinatorial group theory

    CERN Document Server

    Lyndon, Roger C

    2001-01-01

    From the reviews: "This book (...) defines the boundaries of the subject now called combinatorial group theory. (...)it is a considerable achievement to have concentrated a survey of the subject into 339 pages. This includes a substantial and useful bibliography; (over 1100 ÄitemsÜ). ...the book is a valuable and welcome addition to the literature, containing many results not previously available in a book. It will undoubtedly become a standard reference." Mathematical Reviews, AMS, 1979.

  2. Group Variables and Gaming Success.

    Science.gov (United States)

    Norris, Dwight R.; Niebuhr, Robert E.

    1980-01-01

    Describes a study designed to determine the effects of group cohesiveness on group performance in a management game and, to examine the effects voluntary v assigned group membership has on the cohesiveness of the group. (Author/LLS)

  3. Finite groups with transitive semipermutability

    Institute of Scientific and Technical Information of China (English)

    Lifang WANG; Yanming WANG

    2008-01-01

    A group G is said to be a T-group (resp. PT-group, PST-group), if normality (resp. permutability, S-permutability) is a transitive relation. In this paper, we get the characterization of finite solvable PST-groups. We also give a new characterization of finite solvable PT-groups.

  4. Statistical Group Comparison

    CERN Document Server

    Liao, Tim Futing

    2011-01-01

    An incomparably useful examination of statistical methods for comparisonThe nature of doing science, be it natural or social, inevitably calls for comparison. Statistical methods are at the heart of such comparison, for they not only help us gain understanding of the world around us but often define how our research is to be carried out. The need to compare between groups is best exemplified by experiments, which have clearly defined statistical methods. However, true experiments are not always possible. What complicates the matter more is a great deal of diversity in factors that are not inde

  5. Social group utility maximization

    CERN Document Server

    Gong, Xiaowen; Yang, Lei; Zhang, Junshan

    2014-01-01

    This SpringerBrief explains how to leverage mobile users' social relationships to improve the interactions of mobile devices in mobile networks. It develops a social group utility maximization (SGUM) framework that captures diverse social ties of mobile users and diverse physical coupling of mobile devices. Key topics include random access control, power control, spectrum access, and location privacy.This brief also investigates SGUM-based power control game and random access control game, for which it establishes the socially-aware Nash equilibrium (SNE). It then examines the critical SGUM-b

  6. Notes on quantum groups

    Energy Technology Data Exchange (ETDEWEB)

    Pressley, A.; Chari, V. (King' s Coll., London (UK). Dept. of Mathematics Tata Inst. of Fundamental Research, Bombay (India). School of Mathematics)

    1990-12-01

    The authors presents an introduction to quantum groups defined as a deformation of the universal enveloping algebra of a Lie algebra. After the description of Hopf algebras with some examples the approach of Drinfel'd and Jimbo is described, where the quantization of a Lie algebra represents a Hopf algebra, defined over the algebra of formal power series in an indetermined h. The authors show that this approach arises from a r-matrix, which satisfies the classical Yang-Baxter equation. As example quantum sl{sub 2} is considered. Furthermore the approaches of Manin and Woroniwicz and the R-matrix approach are described. (HSI).

  7. Groups and symmetry

    CERN Document Server

    Farmer, David W

    1995-01-01

    In most mathematics textbooks, the most exciting part of mathematics-the process of invention and discovery-is completely hidden from the reader. The aim of Groups and Symmetry is to change all that. By means of a series of carefully selected tasks, this book leads readers to discover some real mathematics. There are no formulas to memorize; no procedures to follow. The book is a guide: Its job is to start you in the right direction and to bring you back if you stray too far. Discovery is left to you. Suitable for a one-semester course at the beginning undergraduate level, there are no prerequ

  8. STEAM GENERATOR GROUP PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Clark, R. A.; Lewis, M

    1985-09-01

    This report is a summary of progress in the Surry Steam Generator Group Project for 1984. Information is presented on the analysis of two baseline eddy current inspections of the generator. Round robin series of tests using standard in-service inspection techniques are described along with some preliminary results. Observations are reported of degradation found on tubing specimens removed from the generator, and on support plates characterized in-situ. Residual stresses measured on a tubing specimen are reported. Two steam generator repair demonstrations are described; one for antivibration bar replacement, and one on tube repair methods. Chemical analyses are shown for sludge samples removed from above the tube sheet.

  9. Applications of Quantum Groups

    Science.gov (United States)

    Chryssomalakos, Chryssomalis

    The main theme of this thesis is the search for applications of Quantum Group and Hopf algebraic concepts and techniques in Physics. We investigate in particular the possibilities that exist in deforming, in a self consistent way, the symmetry structure of physical theories with the hope that the resulting scheme will be of relevance in the description of physical reality. Our choice of topics reflects this motivation: we discuss deformations of rotations and Lorentz boosts, search for integrals on the quantum plane and attempt to Fourier transform functions of non -commuting coordinates. Along the way, more formal considerations prompt us to revisit integration on finite dimensional Hopf algebras, explore the interconnections between various descriptions of the quantum double and derive the algebraic structure of the quantum plane from that of the underlying deformed symmetry group. The material is structured as follows. Chapter 1 introduces the language, basic concepts and notation employed throughout this thesis. Chapter 2 focuses on Hopf algebras viewed as universal envelopes of deformed Lie algebras and their duals. Bicovariant generators enter the discussion as analogues of the classical Lie algebra generators and some of their properties are given. We comment on the geometrical interpretation of the algebraic formulation and introduce computational tools. In chapter 3 we take a close look at the quantum Lorentz Hopf algebra. The basics of complex quantum groups are presented and applied in the derivation of the algebra of the quantum Lorentz generators and its Hopf and involutive structures. We point also to isomorphisms with previous related constructions. The subject of quantum integration is explored in chapter 4. We derive a formula for the integral on a finite dimensional Hopf algebra and show its equivalence to the formulation in terms of the trace of the square of the antipode. Integration on the quantum plane is also examined and a Fourier transform

  10. Finite Symplectic Matrix Groups

    OpenAIRE

    2011-01-01

    The finite subgroups of GL(m, Q) are those subgroups that fix a full lattice in Q^m together with some positive definite symmetric form. A subgroup of GL(m, Q) is called symplectic, if it fixes a nondegenerate skewsymmetric form. Such groups only exist if m is even. A symplectic subgroup of GL(2n, Q) is called maximal finite symplectic if it is not properly contained in some finite symplectic subgroup of GL(2n, Q). This thesis classifies all conjugacy classes of maximal finite symplectic subg...

  11. Outer automorphism groups of certain 1-relator groups

    Institute of Scientific and Technical Information of China (English)

    KIM; Goansu

    2010-01-01

    Grossman first showed that outer automorphism groups of 1-relator groups given by orientable surface groups are residually finite,whence mapping class groups of orientable surfaces are residually finite.Allenby,Kim and Tang showed that outer automorphism groups of cyclically pinched 1-relator groups are residually finite,whence mapping class groups of orientable and non-orientable surfaces are residually finite.In this paper we show that outer automorphism groups of certain conjugacy separable 1-relator groups are residually finite.

  12. Gravitation gauge group

    Energy Technology Data Exchange (ETDEWEB)

    Ter-Kazarian, G. T. [Byurakan Astrophysical Observatory (Armenia)

    1997-06-01

    The suggested theory involves a drastic revision of the role of local internal symmetries in the physical concept of curved geometry. Under the reflection of fields and their dynamics from Minkowski to Riemannian space a standard gauge principle of local internal symmetries has been generalized. A gravitation gauge group is proposed, which is generated by hidden local internal symmetries. In all circumstances, it seemed to be of the greatest importance for the understanding of the physical nature of gravity. The most promising aspect in their approach so far is the fact that the energy-momentum conservation laws of gravitational interacting fields are formulated quite naturally by exploiting all the advantages of auxiliary shadow fields on flat shadow space. The mechanism developed here enables one to infer Einstein`s equation of gravitation, but only with a strong difference from Einstein`s theory at the vital point of well-defined energy-momentum tensor of gravitational field and conservation laws. The gravitational interaction as well as the general distortion of the manifold G(2.2.3) with hidden group U{sup loc} (1) has been considered.

  13. Social group and mobbing

    Directory of Open Access Journals (Sweden)

    Baltezarević Vesna

    2009-01-01

    Full Text Available Our reality, having been subject to the numerous social crises during the last decades of the 20th century, is characterized by frequent incidences of powerlessness and alienation. The man is more frequently a subject to loneliness and overcomes the feeling of worthlessness, no matter whether he considers himself an individual or a part of a whole larger social. Such an environment leads to development of aggression in all fields of ones life. This paper has as an objective the pointing out of the mental harassment that is manifested in the working environment. There is a prevalence of mobbing cases, as a mode of pathological communication. The result of this is that a person, subjected to this kind of abuse, is soon faced with social isolation. This research also aspires to initiate the need for social groups self-organization of which victims are part of. The reaction modality of a social group directly conditions the outcome of the deliberate social drama, one is subjected to it as a result of mobbing.

  14. AO Group Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Olivier, S

    2005-10-04

    The Adaptive Optics (AO) Group in I Division develops and tests a broad range of advanced wavefront control technologies. Current applications focus on: Remote sensing, High power lasers, Astronomy, and Human vision. In the area of remote sensing, the AO Group leads a collaborative effort with LLNL's Nonproliferation, Arms Control & International Security (NAI) Directorate on Enhanced Surveillance Imaging. The ability to detect and identify individual people or vehicles from long-range is an important requirement for proliferation detection and homeland security. High-resolution imaging along horizontal paths through the atmosphere is limited by turbulence, which blurs and distorts the image. For ranges over {approx}one km, visible image resolution can be reduced by over an order of magnitude. We have developed an approach based on speckle imaging that can correct the turbulence-induced blurring and provide high resolution imagery. The system records a series of short exposure images which freeze the atmospheric effects. We can then estimate the image magnitude and phase using a bispectral estimation algorithm which cancels the atmospheric effects while maintaining object information at the diffraction limit of the imaging system.

  15. Communication from ST Group

    CERN Multimedia

    TS Department

    2008-01-01

    In order to prepare the organization of the Open Days, please note that FM Group will not able to take into account either specific requests for waste collection from 2nd to 6th of April, either removal or PC transport requests between the 31st and the 11th of March. We kindly ask you to plan the collection of any type of waste and the urgent transport of office furniture or PC before the 31st of March. Waste collection requests shall be formulated contacting FM Support at 77777 or at the email address mailto:Fm.Support@cern.ch; removal of office furniture or PC transport requests must be made using the EDH ‘Transport request’ form selecting the "Removals" or the "PC transport" category from the drop-down menu. For any question concerning the waste sorting, please consult the following web address: http://dechets-waste.web.cern.ch/dechets-waste/. Thank you for your understanding and collaboration. TS/FM Group

  16. ATLAS Detector Interface Group

    CERN Multimedia

    Mapelli, L

    Originally organised as a sub-system in the DAQ/EF-1 Prototype Project, the Detector Interface Group (DIG) was an information exchange channel between the Detector systems and the Data Acquisition to provide critical detector information for prototype design and detector integration. After the reorganisation of the Trigger/DAQ Project and of Technical Coordination, the necessity to provide an adequate context for integration of detectors with the Trigger and DAQ lead to organisation of the DIG as one of the activities of Technical Coordination. Such an organisation emphasises the ATLAS wide coordination of the Trigger and DAQ exploitation aspects, which go beyond the domain of the Trigger/DAQ project itself. As part of Technical Coordination, the DIG provides the natural environment for the common work of Trigger/DAQ and detector experts. A DIG forum for a wide discussion of all the detector and Trigger/DAQ integration issues. A more restricted DIG group for the practical organisation and implementation o...

  17. Group Life Insurance

    CERN Multimedia

    2013-01-01

    The CERN Administration would like to remind you that staff members and fellows have the possibility to take out a life insurance contract on favourable terms through a Group Life Insurance.   This insurance is provided by the company Helvetia and is available to you on a voluntary basis. The premium, which varies depending on the age and gender of the person insured, is calculated on the basis of the amount of the death benefit chosen by the staff member/fellow and can be purchased in slices of 10,000 CHF.    The contract normally ends at the retirement age (65/67 years) or when the staff member/fellow leaves the Organization. The premium is deducted monthly from the payroll.   Upon retirement, the staff member can opt to maintain his membership under certain conditions.   More information about Group Life Insurance can be found at: Regulations (in French) Table of premiums The Pension Fund Benefit Service &...

  18. Emotional collectives : How groups shape emotions and emotions shape groups

    NARCIS (Netherlands)

    van Kleef, G.A.; Fischer, A.H.

    2016-01-01

    Group settings are epicentres of emotional activity. Yet, the role of emotions in groups is poorly understood. How do group-level phenomena shape group members’ emotional experience and expression? How are emotional expressions recognised, interpreted and shared in group settings? And how do such ex

  19. Representation Theory of Algebraic Groups and Quantum Groups

    CERN Document Server

    Gyoja, A; Shinoda, K-I; Shoji, T; Tanisaki, Toshiyuki

    2010-01-01

    Invited articles by top notch expertsFocus is on topics in representation theory of algebraic groups and quantum groupsOf interest to graduate students and researchers in representation theory, group theory, algebraic geometry, quantum theory and math physics

  20. Graphs, groups and surfaces

    CERN Document Server

    White, AT

    1985-01-01

    The field of topological graph theory has expanded greatly in the ten years since the first edition of this book appeared. The original nine chapters of this classic work have therefore been revised and updated. Six new chapters have been added, dealing with: voltage graphs, non-orientable imbeddings, block designs associated with graph imbeddings, hypergraph imbeddings, map automorphism groups and change ringing.Thirty-two new problems have been added to this new edition, so that there are now 181 in all; 22 of these have been designated as ``difficult'''' and 9 as ``unsolved''''. Three of the four unsolved problems from the first edition have been solved in the ten years between editions; they are now marked as ``difficult''''.

  1. Working Group Report: Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Artuso, M.; et al.,

    2013-10-18

    Sensors play a key role in detecting both charged particles and photons for all three frontiers in Particle Physics. The signals from an individual sensor that can be used include ionization deposited, phonons created, or light emitted from excitations of the material. The individual sensors are then typically arrayed for detection of individual particles or groups of particles. Mounting of new, ever higher performance experiments, often depend on advances in sensors in a range of performance characteristics. These performance metrics can include position resolution for passing particles, time resolution on particles impacting the sensor, and overall rate capabilities. In addition the feasible detector area and cost frequently provides a limit to what can be built and therefore is often another area where improvements are important. Finally, radiation tolerance is becoming a requirement in a broad array of devices. We present a status report on a broad category of sensors, including challenges for the future and work in progress to solve those challenges.

  2. Grouping Notes Through Nodes

    DEFF Research Database (Denmark)

    Dove, Graham; Abildgaard, Sille Julie Jøhnk; Biskjær, Michael Mose

    The Post-ItTM note is a frequently used, and yet seldom studied, design material. We investigate the functions Post-ItTM notes serve when providing cognitive support for creative design team practice. Our investigation considers the ways in which Post-ItTM notes function as design externalisations......, both individually and when grouped, and their role in categorisation in semantic long-term memory. To do this, we adopt a multimodal analytical approach focusing on interaction between humans, and between humans and artefacts, alongside language. We discuss in detail examples of four different...... externalisation functions served by Post-ItTM notes, and show how these functions are present in complex overlapping combinations rather than being discrete. We then show how the temporal development of Post-ItTM note interactions supports categorisation qualities of semantic long-term memory....

  3. Grouping Synonyms by Definitions

    CERN Document Server

    Falk, Ingrid; Jacquey, Evelyne; Venant, Fabienne

    2009-01-01

    We present a method for grouping the synonyms of a lemma according to its dictionary senses. The senses are defined by a large machine readable dictionary for French, the TLFi (Tr\\'esor de la langue fran\\c{c}aise informatis\\'e) and the synonyms are given by 5 synonym dictionaries (also for French). To evaluate the proposed method, we manually constructed a gold standard where for each (word, definition) pair and given the set of synonyms defined for that word by the 5 synonym dictionaries, 4 lexicographers specified the set of synonyms they judge adequate. While inter-annotator agreement ranges on that task from 67% to at best 88% depending on the annotator pair and on the synonym dictionary being considered, the automatic procedure we propose scores a precision of 67% and a recall of 71%. The proposed method is compared with related work namely, word sense disambiguation, synonym lexicon acquisition and WordNet construction.

  4. Renormalization Group Therapy

    CERN Document Server

    Tomboulis, E T

    2007-01-01

    We point out a general problem with the procedures commonly used to obtain improved actions from MCRG decimated configurations. Straightforward measurement of the couplings from the decimated configurations, by one of the known methods, can result into actions that do not correctly reproduce the physics on the undecimated lattice. This is because the decimated configurations are generally not representative of the equilibrium configurations of the assumed form of the effective action at the measured couplings. Curing this involves fine-tuning of the chosen MCRG decimation procedure, which is also dependent on the form assumed for the effective action. We illustrate this in decimation studies of the SU(2) LGT using Swendsen and Double Smeared Blocking decimation procedures. A single-plaquette improved action involving five group representations and free of this pathology is given.

  5. Gutzwiller renormalization group

    Science.gov (United States)

    Lanatà, Nicola; Yao, Yong-Xin; Deng, Xiaoyu; Wang, Cai-Zhuang; Ho, Kai-Ming; Kotliar, Gabriel

    2016-01-01

    We develop a variational scheme called the "Gutzwiller renormalization group" (GRG), which enables us to calculate the ground state of Anderson impurity models (AIM) with arbitrary numerical precision. Our method exploits the low-entanglement property of the ground state of local Hamiltonians in combination with the framework of the Gutzwiller wave function and indicates that the ground state of the AIM has a very simple structure, which can be represented very accurately in terms of a surprisingly small number of variational parameters. We perform benchmark calculations of the single-band AIM that validate our theory and suggest that the GRG might enable us to study complex systems beyond the reach of the other methods presently available and pave the way to interesting generalizations, e.g., to nonequilibrium transport in nanostructures.

  6. NOSS science working group

    Science.gov (United States)

    The members of the NOSS Science Working Group are John Apel, Pacific Marine Environmental Laboratories/NOAA; Tim Barnett, Scripps Institution of Oceanography; Francis Bretherton (chairman), National Center for Atmospheric Research; Otis Brown, University of Miami; Joost Businger, University of Washington; Garrett Campbell, NCAR; Mark Cane, Massachusetts Institute of Technology; Robert Edwards, National Marine Fisheries Service/NOAA; James Mueller, Naval Postgraduate School; Peter Niiler, Oregon State University; James J. O'Brien, Florida State University; Norman Phillips, National Meteorological Center/NOAA; Owen Phillips, The Johns Hopkins University; Stephen Piacsek, NSTL Station, NORDA; Trevor Platt, Bedford Institute of Oceanography; Stephen Pond, University of British Columbia; Stanley Ruttenberg (executive secretary), NCAR; William Schmitz, Woods Hole Oceanographic Institution; Jerry Schubel, State University of New York; Robert Stewart, Scripps; Norbert Untersteiner, NOAA; and Alan Weinstein, Naval Environmental Prediction Research Facility.

  7. Group life insurance

    CERN Multimedia

    2013-01-01

    The CERN Administration wishes to inform staff members and fellows having taken out optional life insurance under the group contract signed by CERN that the following changes to the rules and regulations entered into force on 1 January 2013:   The maximum age for an active member has been extended from 65 to 67 years. The beneficiary clause now allows insured persons to designate one or more persons of their choice to be their beneficiary(-ies), either at the time of taking out the insurance or at a later date, in which case the membership/modification form must be updated accordingly. Beneficiaries must be clearly identified (name, first name, date of birth, address).   The membership/modification form is available on the FP website: http://fp.web.cern.ch/helvetia-life-insurance For further information, please contact: Valentina Clavel (Tel. 73904) Peggy Pithioud (Tel. 72736)

  8. Taxonomic revision of the Malagasy members of the Nesomyrmex angulatus species group using the automated morphological species delineation protocol NC-PART-clustering

    Directory of Open Access Journals (Sweden)

    Sándor Csősz

    2016-03-01

    Full Text Available Background. Applying quantitative morphological approaches in systematics research is a promising way to discover cryptic biological diversity. Information obtained through twenty-first century science poses new challenges to taxonomy by offering the possibility of increased objectivity in independent and automated hypothesis formation. In recent years a number of promising new algorithmic approaches have been developed to recognize morphological diversity among insects based on multivariate morphometric analyses. These algorithms objectively delimit components in the data by automatically assigning objects into clusters. Method. In this paper, hypotheses on the diversity of the Malagasy Nesomyrmex angulatus group are formulated via a highly automated protocol involving a fusion of two algorithms, (1 Nest Centroid clustering (NC clustering and (2 Partitioning Algorithm based on Recursive Thresholding (PART. Both algorithms assign samples into clusters, making the class assignment results of different algorithms readily inferable. The results were tested by confirmatory cross-validated Linear Discriminant Analysis (LOOCV-LDA. Results. Here we reveal the diversity of a unique and largely unexplored fragment of the Malagasy ant fauna using NC-PART-clustering on continuous morphological data, an approach that brings increased objectivity to taxonomy. We describe eight morphologically distinct species, including seven new species: Nesomyrmex angulatus (Mayr, 1862, N. bidentatus sp. n., N. clypeatus sp. n., N. devius sp. n., N. exiguus sp. n., N. fragilis sp. n., N. gracilis sp. n., and N. hirtellus sp. n.. An identification key for their worker castes using morphometric data is provided. Conclusions. Combining the dimensionality reduction feature of NC clustering with the assignment of samples into clusters by PART advances the automatization of morphometry-based alpha taxonomy.

  9. Taxonomic revision of the Malagasy members of the Nesomyrmex angulatus species group using the automated morphological species delineation protocol NC-PART-clustering

    Science.gov (United States)

    Fisher, Brian L.

    2016-01-01

    Background. Applying quantitative morphological approaches in systematics research is a promising way to discover cryptic biological diversity. Information obtained through twenty-first century science poses new challenges to taxonomy by offering the possibility of increased objectivity in independent and automated hypothesis formation. In recent years a number of promising new algorithmic approaches have been developed to recognize morphological diversity among insects based on multivariate morphometric analyses. These algorithms objectively delimit components in the data by automatically assigning objects into clusters. Method. In this paper, hypotheses on the diversity of the Malagasy Nesomyrmex angulatus group are formulated via a highly automated protocol involving a fusion of two algorithms, (1) Nest Centroid clustering (NC clustering) and (2) Partitioning Algorithm based on Recursive Thresholding (PART). Both algorithms assign samples into clusters, making the class assignment results of different algorithms readily inferable. The results were tested by confirmatory cross-validated Linear Discriminant Analysis (LOOCV-LDA). Results. Here we reveal the diversity of a unique and largely unexplored fragment of the Malagasy ant fauna using NC-PART-clustering on continuous morphological data, an approach that brings increased objectivity to taxonomy. We describe eight morphologically distinct species, including seven new species: Nesomyrmex angulatus (Mayr, 1862), N. bidentatus sp. n., N. clypeatus sp. n., N. devius sp. n., N. exiguus sp. n., N. fragilis sp. n., N. gracilis sp. n., and N. hirtellus sp. n.. An identification key for their worker castes using morphometric data is provided. Conclusions. Combining the dimensionality reduction feature of NC clustering with the assignment of samples into clusters by PART advances the automatization of morphometry-based alpha taxonomy. PMID:26989630

  10. The Automorphism Groups of the Groups of Order 32p

    CERN Document Server

    Becker, Elaine W

    2009-01-01

    The results of computer computations determining the automorphism groups of the groups of order 32$p$ for $p \\geq 3$ are given in several tables. Presentations for the automorphism groups of the groups of order 32, which in many cases appear as direct product factors in the automorphism groups of order $32p$, are also presented for completeness. Many of the groups of order 32$p$ with a normal sylow $p$-subgroup have automorphism groups of the form: Hol($C_p$)$ \\times $Invariant Factor. A suggestion is made as to how one might determine this invariant factor using only information on the automorphism group of the 2-group associated with the group of order 32$p$, and the normal subgroup of the 2-group associated with the extension of the group of order $32p$. Some general comments on the groups of order $32p^2$ and their automorphism groups are made. A few explicit calculations for the groups of order $32p^2$ are reported here. Knowing the automorphism groups for the groups of order $32p$ enables us to explicit...

  11. Effect of Bifidobacterium breve on the Intestinal Microbiota of Coeliac Children on a Gluten Free Diet: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Andrea Quagliariello

    2016-10-01

    Full Text Available Coeliac disease (CD is associated with alterations of the intestinal microbiota. Although several Bifidobacterium strains showed anti-inflammatory activity and prevention of toxic gliadin peptides generation in vitro, few data are available on their efficacy when administered to CD subjects. This study evaluated the effect of administration for three months of a food supplement based on two Bifidobacterium breve strains (B632 and BR03 to restore the gut microbial balance in coeliac children on a gluten free diet (GFD. Microbial DNA was extracted from faeces of 40 coeliac children before and after probiotic or placebo administration and 16 healthy children (Control group. Sequencing of the amplified V3-V4 hypervariable region of 16S rRNA gene as well as qPCR of Bidobacterium spp., Lactobacillus spp., Bacteroides fragilis group Clostridium sensu stricto and enterobacteria were performed. The comparison between CD subjects and Control group revealed an alteration in the intestinal microbial composition of coeliacs mainly characterized by a reduction of the Firmicutes/Bacteroidetes ratio, of Actinobacteria and Euryarchaeota. Regarding the effects of the probiotic, an increase of Actinobacteria was found as well as a re-establishment of the physiological Firmicutes/Bacteroidetes ratio. Therefore, a three-month administration of B. breve strains helps in restoring the healthy percentage of main microbial components.

  12. Microbiology of infected poison ivy dermatitis.

    Science.gov (United States)

    Brook, I; Frazier, E H; Yeager, J K

    2000-05-01

    We report the aerobic and anaerobic microbiology of secondarily infected poison ivy dermatitis. The study involved retrospective review of clinical and microbiology laboratory records of patients with secondarily infected poison ivy lesions. Bacterial growth was noted in 33 specimens. Aerobic or facultative anaerobic bacteria only were present in 18 (55%) patients, anaerobic bacteria only in seven (21%), and mixed anaerobic-aerobic bacteria in eight (24%). Forty-five isolates were recovered (1.4 per specimen): 27 aerobic or facultative anaerobic bacteria, and 18 strict anaerobes. The predominant aerobic and facultative anaerobic bacteria were Staphylococcus aureus (13 isolates) and group A beta-haemolytic streptococci (six). The predominant anaerobes were Peptostreptococcus spp. (seven isolates), pigmented Prevotella and Porphyromonas spp. (four) and Fusobacterium spp. (two). Single bacterial isolates were recovered in 18 (55%) patients, eight of which were S. aureus. Nineteen of the organisms isolated from 16 (48%) patients produced the enzyme beta-lactamase. Organisms that resided in the mucous membranes close to the lesions predominated in those infections. Enteric gram-negative rods and Bacteroides fragilis group predominated in leg and buttock lesions. Group A beta-haemolytic streptococci, pigmented Prevotella and Porphyromonas and Fusobacterium spp. were most frequently recovered from lesions of the finger, face and neck. The polymicrobial aetiology of secondarily infected poison ivy lesions, and the association of bacterial flora with the anatomical site of the lesions, are demonstrated.

  13. Structural characterization and MHCII-dependent immunological properties of the zwitterionic O-chain antigen of Morganella morganii.

    Science.gov (United States)

    Young, N Martin; Kreisman, Lori S C; Stupak, Jacek; MacLean, Leann L; Cobb, Brian A; Richards, James C

    2011-10-01

    Morganella morganii is a commensal Gram-negative bacterium that has long been known to produce an antigen bearing phosphocholine groups. We determined the structure of this O-chain antigen and found that its repeating unit also contains a free amino group and a second phosphate: This alternating charge character places the M. morganii O-chain polysaccharide into a small family of zwitterionic polysaccharides (ZPSs) known to induce T-cell-dependent immune responses via presentation by class II major histocompatibility complex (MHCII) molecules. In vitro binding assays demonstrate that this O-chain interacts with MHCII in a manner that competes with binding of the prototypical ZPS antigen PSA from Bacteroides fragilis, despite its lack of a helical structure. Cellular studies also showed that the M. morganii polysaccharide induces activation of CD4(+) T-cells. Antibody binding experiments using acid hydrolyzed fragments representing the monomer and higher oligomers of the repeating unit showed that the phosphocholine group was the dominant element of the epitope with an overall affinity (K(D)) of about 5 × 10(-5) M, a typical value for an IgM anti-carbohydrate antibody but much lower than the affinity for phosphocholine itself. These data show that the structure of the M. morganii polysaccharide contains a unique zwitterionic repeating unit which allows for immune recognition by T-cells, making it the first identified T-cell-dependent O-chain antigen.

  14. Group B Streptococcus and Pregnancy

    Science.gov (United States)

    ... B Strep and Pregnancy • What is group B streptococcus (GBS)? • What does it mean to be colonized ... planned cesarean birth? •Glossary What is group B streptococcus (GBS)? Group B streptococcus is one of the ...

  15. The analytic renormalization group

    Science.gov (United States)

    Ferrari, Frank

    2016-08-01

    Finite temperature Euclidean two-point functions in quantum mechanics or quantum field theory are characterized by a discrete set of Fourier coefficients Gk, k ∈ Z, associated with the Matsubara frequencies νk = 2 πk / β. We show that analyticity implies that the coefficients Gk must satisfy an infinite number of model-independent linear equations that we write down explicitly. In particular, we construct "Analytic Renormalization Group" linear maps Aμ which, for any choice of cut-off μ, allow to express the low energy Fourier coefficients for |νk | < μ (with the possible exception of the zero mode G0), together with the real-time correlators and spectral functions, in terms of the high energy Fourier coefficients for |νk | ≥ μ. Operating a simple numerical algorithm, we show that the exact universal linear constraints on Gk can be used to systematically improve any random approximate data set obtained, for example, from Monte-Carlo simulations. Our results are illustrated on several explicit examples.

  16. Cluster functional renormalization group

    Science.gov (United States)

    Reuther, Johannes; Thomale, Ronny

    2014-01-01

    Functional renormalization group (FRG) has become a diverse and powerful tool to derive effective low-energy scattering vertices of interacting many-body systems. Starting from a free expansion point of the action, the flow of the RG parameter Λ allows us to trace the evolution of the effective one- and two-particle vertices towards low energies by taking into account the vertex corrections between all parquet channels in an unbiased fashion. In this work, we generalize the expansion point at which the diagrammatic resummation procedure is initiated from a free UV limit to a cluster product state. We formulate a cluster FRG scheme where the noninteracting building blocks (i.e., decoupled spin clusters) are treated exactly, and the intercluster couplings are addressed via RG. As a benchmark study, we apply our cluster FRG scheme to the spin-1/2 bilayer Heisenberg model (BHM) on a square lattice where the neighboring sites in the two layers form the individual two-site clusters. Comparing with existing numerical evidence for the BHM, we obtain reasonable findings for the spin susceptibility, the spin-triplet excitation energy, and quasiparticle weight even in coupling regimes close to antiferromagnetic order. The concept of cluster FRG promises applications to a large class of interacting electron systems.

  17. Harmonic Analysis and Group Representation

    CERN Document Server

    Figa-Talamanca, Alessandro

    2011-01-01

    This title includes: Lectures - A. Auslander, R. Tolimeri - Nilpotent groups and abelian varieties, M Cowling - Unitary and uniformly bounded representations of some simple Lie groups, M. Duflo - Construction de representations unitaires d'un groupe de Lie, R. Howe - On a notion of rank for unitary representations of the classical groups, V.S. Varadarajan - Eigenfunction expansions of semisimple Lie groups, and R. Zimmer - Ergodic theory, group representations and rigidity; and, Seminars - A. Koranyi - Some applications of Gelfand pairs in classical analysis.

  18. Group Leader Development: Effects of Personal Growth and Psychoeducational Groups

    Science.gov (United States)

    Ohrt, Jonathan H.; Robinson, E. H., III; Hagedorn, W. Bryce

    2013-01-01

    The purpose of this quasi-experimental study was to compare the effects of personal growth groups and psychoeducational groups on counselor education students' (n = 74) empathy and group leader self-efficacy. Additionally, we compared the degree to which participants in each group valued: (a) cohesion, (b) catharsis, and (c) insight. There were no…

  19. Interagency Advanced Power Group -- Steering group meeting minutes

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-18

    This document contains the draft meeting minutes of the Steering Group of the Interagency Advanced Power Group. Included are the discussions resulting from the presentation of working group reports and the results of a discussion of IAPG policies and procedures. In the appendix are the reports of the following working groups: Electrical, Mechanical, Solar, and Systems.

  20. On the Central Automorphism Groups of Finite p-Groups

    Institute of Scientific and Technical Information of China (English)

    Ali-Reza Jamali; Hamid Mousavi

    2002-01-01

    Using the concept of isoclinism, we study closely the center of the group Autc(G) of central automorphisms for a certain class of finite p-groups G.We also give some necessary and sufficient conditions on a finite purely non-abelian p-group G of class 2 (p odd) for the group Autc(G) to be elementary abelian.

  1. Post-Disaster Social Justice Group Work and Group Supervision

    Science.gov (United States)

    Bemak, Fred; Chung, Rita Chi-Ying

    2011-01-01

    This article discusses post-disaster group counseling and group supervision using a social justice orientation for working with post-disaster survivors from underserved populations. The Disaster Cross-Cultural Counseling model is a culturally responsive group counseling model that infuses social justice into post-disaster group counseling and…

  2. Abstract Lie groups and locally compact topological groups

    Directory of Open Access Journals (Sweden)

    Jacek Lech

    2004-05-01

    Full Text Available We introduce a notion of abstract Lie group by means of the mapping which plays the role of the evolution operator. We show some basic properties of such groups very similar to the fundamentals of the infinite dimensional Lie theory. Next we give remarkable examples of abstract Lie groups which are not necessarily usual Lie groups. In particular, by making use of Yamabe theorem we prove that any locally compact topological group admits the structure of abstract Lie group and that the Lie algebra and the exponential mapping of it coincide with those determined by the Lie group structure.

  3. Emotional collectives: How groups shape emotions and emotions shape groups.

    Science.gov (United States)

    van Kleef, Gerben A; Fischer, Agneta H

    2016-01-01

    Group settings are epicentres of emotional activity. Yet, the role of emotions in groups is poorly understood. How do group-level phenomena shape group members' emotional experience and expression? How are emotional expressions recognised, interpreted and shared in group settings? And how do such expressions influence the emotions, cognitions and behaviours of fellow group members and outside observers? To answer these and other questions, we draw on relevant theoretical perspectives (e.g., intergroup emotions theory, social appraisal theory and emotions as social information theory) and recent empirical findings regarding the role of emotions in groups. We organise our review according to two overarching themes: how groups shape emotions and how emotions shape groups. We show how novel empirical approaches break important new ground in uncovering the role of emotions in groups. Research on emotional collectives is thriving and constitutes a key to understanding the social nature of emotions.

  4. Fermilab Steering Group Report

    Energy Technology Data Exchange (ETDEWEB)

    Steering Group, Fermilab; /Fermilab

    2007-12-01

    The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOvA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building an intense proton facility, Project X, consisting of a linear accelerator with the currently planned characteristics of the ILC combined with Fermilab's existing Recycler Ring and the Main Injector accelerator. The major component of Project X is the linac. Cryomodules, radio-frequency distribution, cryogenics and instrumentation for the linac are the same as or similar to those used in the ILC at a scale of about one percent of a full ILC linac. Project X's intense proton beams would open a path to discovery in neutrino science and in precision physics with charged leptons and quarks. World-leading experiments would allow physicists to address key questions of the Quantum Universe: How did the universe come to be? Are there undiscovered principles of nature: new symmetries, new physical laws? Do all the particles and forces become one? What happened to the antimatter? Building Project X's ILC-like linac would offer substantial support for ILC development by accelerating the

  5. Fermilab Steering Group Report

    Energy Technology Data Exchange (ETDEWEB)

    Beier, Eugene; /Pennsylvania U.; Butler, Joel; /Fermilab; Dawson, Sally; /Brookhaven; Edwards, Helen; /Fermilab; Himel, Thomas; /SLAC; Holmes, Stephen; /Fermilab; Kim, Young-Kee; /Fermilab /Chicago U.; Lankford, Andrew; /UC, Irvine; McGinnis, David; /Fermilab; Nagaitsev, Sergei; /Fermilab; Raubenheimer, Tor; /SLAC /Fermilab

    2007-01-01

    The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOVA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building an intense proton facility, Project X, consisting of a linear accelerator with the currently planned characteristics of the ILC combined with Fermilab's existing Recycler Ring and the Main Injector accelerator. The major component of Project X is the linac. Cryomodules, radio-frequency distribution, cryogenics and instrumentation for the linac are the same as or similar to those used in the ILC at a scale of about one percent of a full ILC linac. Project X's intense proton beams would open a path to discovery in neutrino science and in precision physics with charged leptons and quarks. World-leading experiments would allow physicists to address key questions of the Quantum Universe: How did the universe come to be? Are there undiscovered principles of nature: new symmetries, new physical laws? Do all the particles and forces become one? What happened to the antimatter? Building Project X's ILC-like linac would offer substantial support for ILC development by accelerating the

  6. ON COLEMAN OUTER AUTOMORPHISM GROUPS OF FINITE GROUPS

    Institute of Scientific and Technical Information of China (English)

    海进科; 李正兴

    2014-01-01

    Let G be a finite group and OutCol(G) the Coleman outer automorphism group of G(for the definition, see below). The question whether OutCol(G) is a p′-group naturally arises from the study of the normalizer problem for integral group rings, where p is a prime. In this article, some sufficient conditions for OutCol(G) to be a p′-group are obtained. Our results generalize some well-known theorems.

  7. IgA production in the large intestine is modulated by a different mechanism than in the small intestine: Bacteroides acidifaciens promotes IgA production in the large intestine by inducing germinal center formation and increasing the number of IgA+ B cells.

    Science.gov (United States)

    Yanagibashi, Tsutomu; Hosono, Akira; Oyama, Akihito; Tsuda, Masato; Suzuki, Ami; Hachimura, Satoshi; Takahashi, Yoshimasa; Momose, Yoshika; Itoh, Kikuji; Hirayama, Kazuhiro; Takahashi, Kyoko; Kaminogawa, Shuichi

    2013-04-01

    It has been demonstrated that intestinal commensal bacteria induce immunoglobulin (Ig) A production by promoting the development of gut-associated lymphoid tissues in the small intestine. However, the precise mechanism whereby these bacteria modulate IgA production in the large intestine, which harbors the majority of intestinal commensals, is poorly understood. In addition, it is not known which commensal bacteria induce IgA production in the small intestine and which induce production in the large intestine. To address these issues, we generated gnotobiotic mice mono-associated with different murine commensal bacteria by inoculating germ-free (GF) mice with Lactobacillus johnsonii or Bacteroides acidifaciens. In GF mice, IgA production was barely detectable in the small intestine and was not detected in the large intestine. Interestingly, total IgA secretion in the large intestinal mucosa of B. acidifaciens mono-associated (BA) mice was significantly greater than that of GF and L. johnsonii mono-associated (LJ) mice. However, there was no difference in total IgA production in the small intestine of GF, LJ and BA mice. In addition, in the large intestine of BA mice, the expression of IgA(+) cells and germinal center formation were more remarkable than in GF and LJ mice. Furthermore, B. acidifaciens-specific IgA was detected in the large intestine of BA mice. These results suggest that the production of IgA in the large intestine may be modulated by a different mechanism than that in the small intestine, and that B. acidifaciens is one of the predominant bacteria responsible for promoting IgA production in the large intestine.

  8. Propionibacterium acidipropionici CRL1198 influences the production of acids and the growth of bacterial genera stimulated by inulin in a murine model of cecal slurries.

    Science.gov (United States)

    Lorenzo-Pisarello, M J; Gultemirian, M L; Nieto-Peñalver, C; Perez Chaia, A

    2010-08-01

    Different attempts have been made to improve the health status of humans and animals by increasing the intestinal production of short-chain fatty acids (SCFA) derived from non-digestible carbohydrates fermentation. In this paper we investigate the in vitro production of short-chain fatty acids (SCFA) after addition of inulin, propionibacteria or a combination of both in an experimental model of mice cecal slurries. The development of bacterial genera which are usually stimulated by inulin addition was also investigated. According to our experimental data, acetic acid and butyric acids concentrations increased after incubation in slurries that had no supplements. By contrast, butyric acid concentrations remained in the basal value when supplements were used. Fermentation of only inulin did not increase the concentration of total SCFA. Propionibacterium acidipropionici CRL1198 improved the production of propionic acid in cecal slurries when it was added alone, but the effect was more noticeable in the combination with inulin. A modulation of the global fermentative activity of the cecal microbiota was evidenced by the increase on the ratio propionic acid/SCFA in supplementations with propionibacteria. Statistical analysis of data demonstrated that samples from homogenates with propionibacteria alone or combined with inulin belong to the same cluster. The presence of propionibacteria limited the growth of Bacteroides fragilis and Clostridium hystoliticum groups in slurries with and without inulin. The growth of Bifidobacterium was not modified and the stimulating effect of inulin on lactobacilli disappeared in the presence of propionibacteria. In conclusion, dairy propionibacteria are potential candidates to develop new functional foods helpful to ensure the intestinal production of SCFA during inulin supplementation and to control the overgrowth of bacteria belonging to Bacteroides and Clostridium genera.

  9. Anomaly-safe discrete groups

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Mu-Chun, E-mail: muchunc@uci.edu [Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575 (United States); Fallbacher, Maximilian, E-mail: m.fallbacher@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Ratz, Michael, E-mail: michael.ratz@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Trautner, Andreas, E-mail: andreas.trautner@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Excellence Cluster Universe, Boltzmannstraße 2, 85748 Garching (Germany); Vaudrevange, Patrick K.S., E-mail: patrick.vaudrevange@tum.de [Excellence Cluster Universe, Boltzmannstraße 2, 85748 Garching (Germany); TUM Institute for Advanced Study, Lichtenbergstraße 2a, 85748 Garching (Germany); Arnold Sommerfeld Center for Theoretical Physics, Ludwig–Maximilians–Universität München, Theresienstraße 37, 80333 München (Germany)

    2015-07-30

    We show that there is a class of finite groups, the so-called perfect groups, which cannot exhibit anomalies. This implies that all non-Abelian finite simple groups are anomaly-free. On the other hand, non-perfect groups generically suffer from anomalies. We present two different ways that allow one to understand these statements.

  10. Anomaly-safe discrete groups

    Directory of Open Access Journals (Sweden)

    Mu-Chun Chen

    2015-07-01

    Full Text Available We show that there is a class of finite groups, the so-called perfect groups, which cannot exhibit anomalies. This implies that all non-Abelian finite simple groups are anomaly-free. On the other hand, non-perfect groups generically suffer from anomalies. We present two different ways that allow one to understand these statements.

  11. 2010 Chemical Working Group Status

    Science.gov (United States)

    Reid, Concha M.

    2010-01-01

    The Steering Group for the Interagency Advanced Power Group (IAPG) held their business meeting on November 30-December 1st in McLean, Virginia. Status reports were presented from each of the IAPG's Working Groups. These charts contain a brief summary of the IAPG Chemical Working Group's activities during 2010 and its plans for 2011.

  12. About Hebei Jianxin Construction Group

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Hebei Jianxin Construction (Group) Ltd. was incorporated in August 1984. As the holding company, Hebei Jianxin Construction (Group)Ltd. along with five companies under its holding, such as Baoding New Generation Real Estate Development Co., Ltd. and Baoding New Generation Property Management Co., Ltd., formed Hebei Jianxin Architectural Group (hereafter, the Group).

  13. Maximal subgroups of finite groups

    Directory of Open Access Journals (Sweden)

    S. Srinivasan

    1990-01-01

    Full Text Available In finite groups maximal subgroups play a very important role. Results in the literature show that if the maximal subgroup has a very small index in the whole group then it influences the structure of the group itself. In this paper we study the case when the index of the maximal subgroups of the groups have a special type of relation with the Fitting subgroup of the group.

  14. Interrelation of group, micro-group and interpersonal identities of employees in production groups

    Directory of Open Access Journals (Sweden)

    Sidorenkov A.V.

    2016-12-01

    Full Text Available The article represents the results of mathematical and statistical analysis of the links between the levels of the identity of employees (group, micro-group and interpersonal by three components (cognitive, affective and behavioral in 37 industrial groups with expertise in different fields. The significant linear relationship between micro-group and interpersonal identity (for all components, high linear relationship between group identity and micro-group identity (only for affective component and the lack of linear relationship between the components of inter- personal and group identity are revealed. Higher influence of group identity on micro-group (for all components and interpersonal identity (for cognitive and behavioral components is found out in the totality of intercorrelation between group, micro-group and interpersonal identities. Non-linear relationship between group and micro-group identity for all components is revealed. This non-linear relation indicates that increase in expressiveness of one of the components of group iden- tity leads to decrease in expressiveness of the respective component of micro-group identity. This effect occurs until definite moment, after which, on the contrary, further reinforcement of the components of group identity leads to the increase in expressiveness of micro-group identity. These established consistent patterns are interpreted in the article.

  15. High occurrence of Fusobacterium nucleatum and Clostridium difficile in the intestinal microbiota of colorectal carcinoma patients

    Directory of Open Access Journals (Sweden)

    Márcia H. Fukugaiti

    2015-01-01

    Full Text Available AbstractColorectal carcinoma is considered the fourth leading cause of cancer deaths worldwide. Several microorganisms have been associated with carcinogenesis, including Enterococcus spp., Helicobacter pylori, enterotoxigenic Bacteroides fragilis, pathogenic E. coli strains and oral Fusobacterium. Here we qualitatively and quantitatively evaluated the presence of oral and intestinal microorganisms in the fecal microbiota of colorectal cancer patients and healthy controls. Seventeen patients (between 49 and 70 years-old visiting the Cancer Institute of the Sao Paulo State were selected, 7 of whom were diagnosed with colorectal carcinoma. Bacterial detection was performed by qRT-PCR. Although all of the tested bacteria were detected in the majority of the fecal samples, quantitative differences between the Cancer Group and healthy controls were detected only for F. nucleatum and C. difficile. The three tested oral microorganisms were frequently observed, suggesting a need for furthers studies into a potential role for these bacteria during colorectal carcinoma pathogenesis. Despite the small number of patients included in this study, we were able to detect significantly more F. nucleatumand C. difficile in the Cancer Group patients compared to healthy controls, suggesting a possible role of these bacteria in colon carcinogenesis. This finding should be considered when screening for colorectal cancer.

  16. Role of anaerobes in acute pelvic inflammatory disease

    Directory of Open Access Journals (Sweden)

    Saini S

    2003-01-01

    Full Text Available Pouch of Douglas aspirates were collected from 50 women with history and examination suggestive of acute pelvic inflammatory disease (PID and 20 healthy women admitted for tubal ligation served as control. A total of 57 microorganisms were isolated from 37 patients out of 50 in study group. Of 37 positive cultures 21(56.7% were monomicrobial and 16(43.2% were polymicrobial. Most common symptom in study group was lower abdominal pain (90%, vaginal discharge (70% and irregular bleeding (40% and 30% patients had history of intrauterine contraceptive device (IUCD implantation. The predominant aerobic isolates were Escherichia coli, Coagulase Negative Staphylococcus (CONS, Staphylococcus aureus, Klebsiella pneumoniae while common anaerobes were Bacteroides fragilis, Prevotella melaninogenica, Fusobacterium nucleatum and Peptostreptococcus spp. Our study shows that cefotaxime, cefuroxime and gentamicin may be used for gram negative aerobic bacilli; cloxacillin, cephaloridine and erythromycin for aerobic gram positive cocci and amikacin and ceftazidime for Pseudomonas aeruginosa. Thus for optimum therapy of acute PID it is beneficial to keep in mind major conceptual changes and therapeutic realities that have influenced current understanding of acute PID and have affected the choice of therapy.

  17. Role of anaerobes in acute pelvic inflammatory disease.

    Science.gov (United States)

    Saini, S; Gupta, N; Batra, G; Arora, D R

    2003-01-01

    Pouch of Douglas aspirates were collected from 50 women with history and examination suggestive of acute pelvic inflammatory disease (PID) and 20 healthy women admitted for tubal ligation served as control. A total of 57 microorganisms were isolated from 37 patients out of 50 in study group. Of 37 positive cultures 21(56.7%) were monomicrobial and 16(43.2%) were polymicrobial. Most common symptom in study group was lower abdominal pain (90%), vaginal discharge (70%) and irregular bleeding (40%) and 30% patients had history of intrauterine contraceptive device (IUCD) implantation. The predominant aerobic isolates were Escherichia coli, Coagulase Negative Staphylococcus (CONS), Staphylococcus aureus, Klebsiella pneumoniae while common anaerobes were Bacteroides fragilis, Prevotella melaninogenica, Fusobacterium nucleatum and Peptostreptococcus spp. Our study shows that cefotaxime, cefuroxime and gentamicin may be used for gram negative aerobic bacilli; cloxacillin, cephaloridine and erythromycin for aerobic gram positive cocci and amikacin and ceftazidime for Pseudomonas aeruginosa. Thus for optimum therapy of acute PID it is beneficial to keep in mind major conceptual changes and therapeutic realities that have influenced current understanding of acute PID and have affected the choice of therapy.

  18. Does group efficacy increase group identification? Resolving their paradoxical relationship

    NARCIS (Netherlands)

    van Zomeren, Martijn; Leach, Colin Wayne; Spears, Russell

    2010-01-01

    Although group identification and group efficacy are both important predictors of collective action against collective disadvantage, there is mixed evidence for their (causal) relationship. Meta-analytic and correlational evidence suggests an overall positive relationship that has been interpreted a

  19. Groups possessing extensive hierarchical decompositions

    CERN Document Server

    Januszkiewicz, T; Leary, I J

    2009-01-01

    Kropholler's class of groups is the smallest class of groups which contains all finite groups and is closed under the following operator: whenever $G$ admits a finite-dimensional contractible $G$-CW-complex in which all stabilizer groups are in the class, then $G$ is itself in the class. Kropholler's class admits a hierarchical structure, i.e., a natural filtration indexed by the ordinals. For example, stage 0 of the hierarchy is the class of all finite groups, and stage 1 contains all groups of finite virtual cohomological dimension. We show that for each countable ordinal $\\alpha$, there is a countable group that is in Kropholler's class which does not appear until the $\\alpha+1$st stage of the hierarchy. Previously this was known only for $\\alpha= 0$, 1 and 2. The groups that we construct contain torsion. We also review the construction of a torsion-free group that lies in the third stage of the hierarchy.

  20. Secure Group Communications for Large Dynamic Multicast Group

    Institute of Scientific and Technical Information of China (English)

    Liu Jing; Zhou Mingtian

    2003-01-01

    As the major problem in multicast security, the group key management has been the focus of research But few results are satisfactory. In this paper, the problems of group key management and access control for large dynamic multicast group have been researched and a solution based on SubGroup Secure Controllers (SGSCs) is presented, which solves many problems in IOLUS system and WGL scheme.

  1. Growth of Automorphism Groups of Relatively Free Groups

    Institute of Scientific and Technical Information of China (English)

    V. Drensky; A.I. Papistas

    2001-01-01

    We introduce a new growth function for automorphism groups of residually nilpotent relatively free groups Fn(V) and study its behavior. We prove that, under some natural restrictions, the growth of the group of tame automorphisms of Fn(V) is equal to the growth of the automorphism group of Fn(V), and coincides with the growth of the Lie algebra over Q associated with Fn (V). Applications of our techniques are given.

  2. Group Milieu in systemic and psychodynamic group therapy

    DEFF Research Database (Denmark)

    Lau, Marianne Engelbrecht

    group was characterized by statistically significant highest scores on Relationship (ES = 1.27) and System Maintenance / Change Dimension (ES= 1.28), while the scores for Personal Growth Dimension were comparable in the two groups. Group S had statistically significant higher scores on the following...... subscales: Cohesion (pLeader support (p=0.001), Expressiveness (p

  3. Re-Examining Group Development in Adventure Therapy Groups.

    Science.gov (United States)

    DeGraaf, Don; Ashby, Jeff

    1998-01-01

    Small-group development is an important aspect of adventure therapy. Supplementing knowledge of sequential stages of group development with knowledge concerning within-stage nonsequential development yields a richer understanding of groups. Integrating elements of the individual counseling relationship (working alliance, transference, and real…

  4. How Much "Group" Is There in Online Group Work?

    Science.gov (United States)

    Lowes, Susan

    2014-01-01

    The ability to work in groups across time and space has become a frequent requirement for the workplace and is increasingly common in higher education, but there is a surprising lack of research on how online groups work. This research applies analytic approaches used in studies of face-to-face classroom "talk" to multiple groups in two…

  5. Intensifying the Group Member's Experience Using the Group Log.

    Science.gov (United States)

    Valine, Warren J.

    1983-01-01

    Presents the use of a group log in which members analyze the content and process of each session using a suggested format. The log promotes dialogue between the leader and each group member and involves members more fully in the group process. Feedback indicates the log is valuable. (JAC)

  6. An Exploration of Group and Member Development in Experiential Groups

    Science.gov (United States)

    Ohrt, Jonathan H.; Prochenko, Yulia; Stulmaker, Hayley; Huffman, David; Fernando, Delini; Swan, Karrie

    2014-01-01

    In this phenomenological study, we explored 52 group members' development in experiential groups. Specifically, participants completed 10 weekly journal reflections about their experiences as members and also reflected on the group's overall development. Four overall themes--exploration, transition, working, closure--as well as multiple subthemes…

  7. Quantization on nilpotent Lie groups

    CERN Document Server

    Fischer, Veronique

    2016-01-01

    This book presents a consistent development of the Kohn-Nirenberg type global quantization theory in the setting of graded nilpotent Lie groups in terms of their representations. It contains a detailed exposition of related background topics on homogeneous Lie groups, nilpotent Lie groups, and the analysis of Rockland operators on graded Lie groups together with their associated Sobolev spaces. For the specific example of the Heisenberg group the theory is illustrated in detail. In addition, the book features a brief account of the corresponding quantization theory in the setting of compact Lie groups. The monograph is the winner of the 2014 Ferran Sunyer i Balaguer Prize.

  8. Group analysis of differential equations

    CERN Document Server

    Ovsiannikov, L V

    1982-01-01

    Group Analysis of Differential Equations provides a systematic exposition of the theory of Lie groups and Lie algebras and its application to creating algorithms for solving the problems of the group analysis of differential equations.This text is organized into eight chapters. Chapters I to III describe the one-parameter group with its tangential field of vectors. The nonstandard treatment of the Banach Lie groups is reviewed in Chapter IV, including a discussion of the complete theory of Lie group transformations. Chapters V and VI cover the construction of partial solution classes for the g

  9. Saving Face and Group Identity

    DEFF Research Database (Denmark)

    Eriksson, Tor; Mao, Lei; Villeval, Marie-Claire

    2015-01-01

    their self- but also other group members' image. This behavior is frequent even in the absence of group identity. When group identity is more salient, individuals help regardless of whether the least performer is an in-group or an out-group. This suggests that saving others' face is a strong social norm.......Are people willing to sacrifice resources to save one's and others' face? In a laboratory experiment, we study whether individuals forego resources to avoid the public exposure of the least performer in their group. We show that a majority of individuals are willing to pay to preserve not only...

  10. Group Lasso with Overlaps: the Latent Group Lasso approach

    CERN Document Server

    Obozinski, Guillaume; Vert, Jean-Philippe

    2011-01-01

    We study a norm for structured sparsity which leads to sparse linear predictors whose supports are unions of prede ned overlapping groups of variables. We call the obtained formulation latent group Lasso, since it is based on applying the usual group Lasso penalty on a set of latent variables. A detailed analysis of the norm and its properties is presented and we characterize conditions under which the set of groups associated with latent variables are correctly identi ed. We motivate and discuss the delicate choice of weights associated to each group, and illustrate this approach on simulated data and on the problem of breast cancer prognosis from gene expression data.

  11. Moxibustion inhibits interleukin-12 and tumor necrosis factor alpha and modulates intestinal flora in rat with ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Xiao-Mei Wang; Yuan Lu; Lu-Yi Wu; Shu-Guang Yu; Bai-Xiao Zhao; Hong-Yi Hu; Huan-Gan Wu

    2012-01-01

    AIM:To investigate the effect of moxibustion on intestinal flora and release of interleukin-12 (IL-12) and tumor necrosis factor-α (TNF-α) from the colon in rat with ulcerative colitis (UC).METHODS:A rat model of UC was established by local stimulation of the intestine with supernatant from colonic contents harvested from human UC patients.A total of 40 male Sprague-Dawley rats were randomly divided into the following groups:normal (sham),model (UC),herb-partition moxibustion (HPM-treated),and positive control sulfasalazine (SA-treated).Rats treated with HPM received HPM at acupuncture points ST25 and RN6,once a day for 15 min,for a total of 8 d.Rats in the SA group were perfused with SA twice a day for 8 d.The colonic histopathology was observed by hematoxylin-eosin.The levels of intestinal flora,including Bifidobacterium,Lactobacillus,Escherichia coli (E.coli),and Bacteroides fragilis (B.fragilis),were tested by real-time quantitative polymerase chain reaction to detect bacterial 16S rRNA/DNA in order to determine DNA copy numbers of each specific species.Immunohistochemical assays were used to observe the expression of TNF-α and IL-12 in the rat colons.RESULTS:HPM treatment inhibited immunopathology in colonic tissues of UC rats; the general morphological score and the immunopathological score were significantly decreased in the HPM and SA groups compared with the model group [3.5 (2.0-4.0),3.0 (1.5-3.5) vs 6.0 (5.5-7.0),P < 0.05 for the general morphological score,and 3.00 (2.00-3.50),3.00 (2.50-3.50) vs 5.00 (4.50-5.50),P < 0.01 for the immunopathological score].As measured by DNA copy number,we found that Bilidobacterium and Lactobacillus,which are associated with a healthy colon,were significantly higher in the HPM and SA groups than in the model group (1.395± 1.339,1.461 ± 1.152 vs 0.045 ± 0.036,P < 0.01 for Bifidobacterium,and 0.395 ± 0.325,0.851 ± 0.651 vs 0.0015 ± 0.0014,P < 0.01 for Lactobacillus).On the other hand,E.coli and B.fragilis

  12. Riemannian means on special euclidean group and unipotent matrices group.

    Science.gov (United States)

    Duan, Xiaomin; Sun, Huafei; Peng, Linyu

    2013-01-01

    Among the noncompact matrix Lie groups, the special Euclidean group and the unipotent matrix group play important roles in both theoretic and applied studies. The Riemannian means of a finite set of the given points on the two matrix groups are investigated, respectively. Based on the left invariant metric on the matrix Lie groups, the geodesic between any two points is gotten. And the sum of the geodesic distances is taken as the cost function, whose minimizer is the Riemannian mean. Moreover, a Riemannian gradient algorithm for computing the Riemannian mean on the special Euclidean group and an iterative formula for that on the unipotent matrix group are proposed, respectively. Finally, several numerical simulations in the 3-dimensional case are given to illustrate our results.

  13. Neutral Hydrogen in Galaxy Groups

    CERN Document Server

    McKay, N P F; Brough, S; Forbes, D A; Barnes, D G

    2002-01-01

    We present preliminary results from a study of the neutral hydrogen (HI) properties of an X-ray selected sample of nearby loose galaxy groups. This forms part of a multi-wavelength investigation (X-ray, optical and radio) of the formation and evolution of galaxies within a group environment. Some initial findings of an ATNF Parkes Multibeam wide-area neutral hydrogen imaging survey of 17 nearby galaxy groups include two new, potentially isolated clouds of HI in the NGC 1052 and NGC 5044 groups and significant amounts of HI within the group virial radii of groups NGC 3557 and IC 1459 - two groups with complex X-ray structures that suggest they may still be in the act of virialisation. Here we present ATCA high-resolution synthesis-imaging follow-up observations of the distribution and kinematics of HI in these four groups.

  14. Group performance and decision making.

    Science.gov (United States)

    Kerr, Norbert L; Tindale, R Scott

    2004-01-01

    Theory and research on small group performance and decision making is reviewed. Recent trends in group performance research have found that process gains as well as losses are possible, and both are frequently explained by situational and procedural contexts that differentially affect motivation and resource coordination. Research has continued on classic topics (e.g., brainstorming, group goal setting, stress, and group performance) and relatively new areas (e.g., collective induction). Group decision making research has focused on preference combination for continuous response distributions and group information processing. New approaches (e.g., group-level signal detection) and traditional topics (e.g., groupthink) are discussed. New directions, such as nonlinear dynamic systems, evolutionary adaptation, and technological advances, should keep small group research vigorous well into the future.

  15. On -supersolvability of finite groups

    Indian Academy of Sciences (India)

    Izabela Agata Malinowska

    2015-05-01

    A number of authors have studied the structure of a group under the assumption that some subgroups of are well located in . We will obtain some new criteria of -supersolvability and -nilpotency of groups.

  16. PRICE DISCRIMINATION THROUGH GROUP BUYING

    OpenAIRE

    2016-01-01

    This paper argues that when consumers are heterogeneous in group-buying costs, a monopolist seller may practice price discrimination through inducing certain consumers to participate in group buying. In contrast to the standard model, the optimal quantity/quality level for low valuation consumers without group buying is further distorted downward, whereas the levels for other consumers are socially optimal. Inducing group buying is more favorable when the proportion of high valuation consumer...

  17. Internal communication in corporate groups

    OpenAIRE

    Grzesik, Katarzyna

    2015-01-01

    This chapter is dedicated to internal communication in corporate groups. It discusses internal communication systems operating in the explored corporate groups and their significance for effective human resources management in those organisations. The chapter presents both the theoretical analysis based on the results of literature studies, and empirical research carried out in the explored groups. Narodowe Centrum Nauki Katarzyna Grzesik

  18. Group Cooperation in Outdoor Education

    Science.gov (United States)

    Matthews, Bruce E.

    1978-01-01

    Utilizing the Beatles' Yellow Submarine fantasy (e.g., the Blue Meanies), this outdoor education program is designed for sixth graders and special education students. Activities developed at the Cortland Resident Outdoor Education Camp include a series of group stress/challenge activities to be accomplished by everyone in the group, as a group.…

  19. On The Harmonic Oscillator Group

    CERN Document Server

    Lopez, Raquel M; Vega-Guzman, Jose M

    2011-01-01

    We discuss the maximum kinematical invariance group of the quantum harmonic oscillator from a view point of the Ermakov-type system. The invariance group of generalized driven harmonic oscillator is shown to be isomorphic to the corresponding Schroedinger group of the free particle.

  20. Group Assessment and Structured Learning.

    Science.gov (United States)

    Lambert, Warren; And Others

    1980-01-01

    Two new techniques that were used with a group of seven blind, multiply handicapped young adults in a half-way house are described. Structured learning therapy is a social skills training technique and group assessment is a method of averaging psychological data on a group of clients to facilitate program planning based on client needs.…

  1. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive...

  2. The Variety of Group Learning

    Institute of Scientific and Technical Information of China (English)

    HaoYanyan; YuZhihao

    2004-01-01

    With the rapid enrollment expansion in the recent years,the author feels it urgent to reform the traditional group work,and therefore to form a new and more effective pattern of group learning. The new of group word is based on the principles of cooperation and that of the task with the more flexible marking system.

  3. Empowering Groups that Enable Play

    Science.gov (United States)

    Wilson, David Sloan; Marshall, Danielle; Iserhott, Hindi

    2011-01-01

    Creating play environments for children usually requires groups of adults working together. An extensive scientific literature describes how groups function to achieve shared goals in general terms, and groups attempting to empower play may find this literature useful. Design principles for managing natural resources, identified by Elinor Ostrom…

  4. Stereotypes of Norwegian social groups.

    Science.gov (United States)

    Bye, Hege H; Herrebrøden, Henrik; Hjetland, Gunnhild J; Røyset, Guro Ø; Westby, Linda L

    2014-10-01

    We present a pilot study and two main studies that address the nature of stereotypes of social groups in Norway within the framework of the Stereotype Content Model (SCM). The first study focused on stereotypes of a wide range of groups across categories such as gender, age, religious conviction, socioeconomic and health status. The second study focused on stereotypes of immigrant groups. Participants (n = 244 and n = 63, respectively) rated the groups on perceived warmth, competence, status, and competition. Results from both studies support the applicability of the SCM in Norway and provides a unique insight into stereotypes of Norwegian social groups.

  5. Defining and Classifying Interest Groups

    DEFF Research Database (Denmark)

    Baroni, Laura; Carroll, Brendan; Chalmers, Adam;

    2014-01-01

    The interest group concept is defined in many different ways in the existing literature and a range of different classification schemes are employed. This complicates comparisons between different studies and their findings. One of the important tasks faced by interest group scholars engaged...... in large-N studies is therefore to define the concept of an interest group and to determine which classification scheme to use for different group types. After reviewing the existing literature, this article sets out to compare different approaches to defining and classifying interest groups with a sample...

  6. Locally minimal topological groups 1

    OpenAIRE

    Chasco, María Jesús; Dikranjan, Dikran N.; Außenhofer, Lydia; Domínguez, Xabier

    2015-01-01

    The aim of this paper is to go deeper into the study of local minimality and its connection to some naturally related properties. A Hausdorff topological group ▫$(G,tau)$▫ is called locally minimal if there exists a neighborhood ▫$U$▫ of 0 in ▫$tau$▫ such that ▫$U$▫ fails to be a neighborhood of zero in any Hausdorff group topology on ▫$G$▫ which is strictly coarser than ▫$tau$▫. Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all mini...

  7. The "group" in obstetric psychoprophylaxis.

    Science.gov (United States)

    Volpe, B; Tenaglia, F; Fede, T; Cerutti, R

    1983-01-01

    In the practice of obstetric psychoprophylaxis every method employed considered always the group both from a psychological and a pedagogic point of view. Today the group of pregnant women (or couples) is considered under various aspects: - psychological: the group as a support for members with regard to maternal and parental emotional feelings; - anthropological: the group fills up an empty vital space and becomes a "rite de passage" from a state of social identity to another one; - social: the group is a significative cultural intermediary between health services and the women-patient. The knowledge of these aspects becomes an important methodological support for group conductors. We present an analysis of our experience with groups and how this has affected the Psychoprophylaxis in the last years.

  8. Little Groups of Preon Branes

    CERN Document Server

    Mkrtchyan, H G

    2003-01-01

    Little groups for preon branes (i.e. configurations of branes with maximal (n-1)/n fraction of survived supersymmetry) for dimensions d=2,3,...,11 are calculated for all massless, and partially for massive orbits. For massless orbits little groups are semidirect product of d-2 translational group $T_{d-2}$ on a subgroup of (SO(d-2) $\\times$ R-invariance) group. E.g. at d=9 the subgroup is exceptional $G_2$ group. It is also argued, that 11d Majorana spinor invariants, which distinguish orbits, are actually invariant under d=2+10 Lorentz group. Possible applications of these results include construction of field theories in generalized space-times with brane charges coordinates, different problems of group's representations decompositions, spin-statistics issues.

  9. Little Groups of Preon Branes

    Science.gov (United States)

    MKRTCHYAN, H.; MKRTCHYAN, R.

    Little groups for preon branes (i.e. configurations of branes with maximal (n-1)/n fraction of survived supersymmetry) for dimensions d=2,3,…,11 are calculated for all massless, and partially for massive orbits. For massless orbits little groups are semidirect product of d-2 translational group Td-2 on a subgroup of (SO(d-2) × R-invariance) group. E.g. at d=9 the subgroup is exceptional G2 group. It is also argued, that 11D Majorana spinor invariants, which distinguish orbits, are actually invariant under d=2+10 Lorentz group. Possible applications of these results include construction of field theories in generalized spacetimes with brane charges coordinates, different problems of group's representations decompositions, spin-statistics issues.

  10. Ethnic group identification and group evaluation among minority and majority groups: testing the multiculturalism hypothesis.

    Science.gov (United States)

    Verkuyten, Maykel

    2005-01-01

    Following social identity theory, the author hypothesized that members of minority groups are more likely than majority group members to endorse multiculturalism more strongly and assimilationist thinking less strongly. In addition, the multiculturalism hypothesis proposes that the more minority groups endorse the ideology of multiculturalism (or assimilationism), the more (or less) likely they will be to identify with their ethnic in-group and to show positive in-group evaluation. In contrast, the more majority group members endorse multiculturalism (or assimilationism), the less (or more) likely they are to identify with their ethnic group and to show negative out-group evaluation. Results from 4 studies (correlational and experimental) provide support for this hypothesis among Dutch and Turkish participants living in the Netherlands.

  11. La fasciite nécrosante post opératoire: une complication rare et mortelle

    Science.gov (United States)

    Ghezala, Hassen Ben; Feriani, Najla

    2016-01-01

    Les complications pariétales post opératoire peuvent être exceptionnellement majeures et graves menaçant le pronostic vital. La fasciite nécrosante est une infection rare de la peau et des tissus sous-cutanés profonds, se propageant le long des fascias et du tissu adipeux. Elle est surtout causée par le streptocoque du groupe A Streptococcus pyogènes mais également par d'autres bactéries telles que Vibrio vulnificus, clostridium perfringens ou Bacteroides fragilis. La fasciite nécrosante est une véritable urgence médicochirurgicale. Nous rapportons dans ce travail une observation très rare d'une gangrène pariétale abdominale survenant chez une patiente de 75 ans au cinquième jour post-opératoire d'un kyste de l'ovaire. L’évolution était marquée par l'installation d'un état de choc septique réfractaire rapidement fatal à J3 de la prise en charge. PMID:27279950

  12. Associations among Human-Associated Fecal Contamination, Microcystis aeruginosa, and Microcystin at Lake Erie Beaches.

    Science.gov (United States)

    Lee, Cheonghoon; Marion, Jason W; Cheung, Melissa; Lee, Chang Soo; Lee, Jiyoung

    2015-09-11

    Lake Erie beaches exhibit impaired water quality due to fecal contamination and cyanobacterial blooms, though few studies address potential relationships between these two public health hazards. Using quantitative polymerase chain reaction (qPCR), Microcystis aeruginosa was monitored in conjunction with a human-associated fecal marker (Bacteroides fragilis group; g-Bfra), microcystin, and water quality parameters at two beaches to evaluate their potential associations. During the summer of 2010, water samples were collected 32 times from both Euclid and Villa Angela beaches. The phycocyanin intergenic spacer (PC-IGS) and the microcystin-producing (mcyA) gene in M. aeruginosa were quantified with qPCR. PC-IGS and mcyA were detected in 50.0% and 39.1% of samples, respectively, and showed increased occurrences after mid-August. Correlation and regression analyses showed that water temperature was negatively correlated with M. aeruginosa markers and microcystin. The densities of mcyA and the g-Bfra were predicted by nitrate, implicating fecal contamination as contributing to the growth of M. aeruginosa by nitrate loading. Microcystin was correlated with mcyA (r = 0.413, p microcystin production. Additionally, microcystin was correlated with total phosphorus (r = 0.628, p microcystin concentrations at Euclid.

  13. Expanded therapeutic potential in activity space of next-generation 5-nitroimidazole antimicrobials with broad structural diversity.

    Science.gov (United States)

    Miyamoto, Yukiko; Kalisiak, Jaroslaw; Korthals, Keith; Lauwaet, Tineke; Cheung, Dae Young; Lozano, Ricardo; Cobo, Eduardo R; Upcroft, Peter; Upcroft, Jacqueline A; Berg, Douglas E; Gillin, Frances D; Fokin, Valery V; Sharpless, K Barry; Eckmann, Lars

    2013-10-22

    Metronidazole and other 5-nitroimidazoles (5-NI) are among the most effective antimicrobials available against many important anaerobic pathogens, but evolving resistance is threatening their long-term clinical utility. The common 5-NIs were developed decades ago, yet little 5-NI drug development has since taken place, leaving the true potential of this important drug class unexplored. Here we report on a unique approach to the modular synthesis of diversified 5-NIs for broad exploration of their antimicrobial potential. Many of the more than 650 synthesized compounds, carrying structurally diverse functional groups, have vastly improved activity against a range of microbes, including the pathogenic protozoa Giardia lamblia and Trichomonas vaginalis, and the bacterial pathogens Helicobacter pylori, Clostridium difficile, and Bacteroides fragilis. Furthermore, they can overcome different forms of drug resistance, and are active and nontoxic in animal infection models. These findings provide impetus to the development of structurally diverse, next-generation 5-NI drugs as agents in the antimicrobial armamentarium, thus ensuring their future viability as primary therapeutic agents against many clinically important infections.

  14. Use of antibiotics in the management of postirradiation wound infection and sepsis

    Energy Technology Data Exchange (ETDEWEB)

    Brook, I.

    1988-07-01

    Ionizing gamma irradiation depresses the host defenses and enhances the susceptibility of the immunocompromised host to local and systemic infection due to endogenous or exogenous microorganisms. Trauma and wounding act synergistically and decrease the survival after exposure to irradiation. The current antimicrobial agents suitable for controlling serious infections and their use in post irradiation local and systemic infection with and without trauma are discussed. The experience gained in managing immunocompromised patients following chemotherapy is reviewed. Empiric single agent or combination agent therapy should be directed at the eradication of potential gram-negative as well as gram-positive pathogens. The most important organisms known to cause these infections are Pseudomonas sp. and Enterobacteriaceae. Management of intra-abdominal infections following trauma should include early surgical correlation and antimicrobials directed against the Bacteroides fragilis group and Enterobacteriaceae. Staphylococcus aureus and Streptococcus pyogenes cause most skin and soft tissue infections following trauma. Chemoprophylaxis of enteric sources of systemic infection can be achieved by antimicrobials that selectively inhibit the Enterobacteriaceae sp. and preserve the anaerobic flora. The management of infection in the injured and irradiated host includes supportive and restorative therapy. Supportive therapy includes debridement and cleansing of wounds, fluids, immunoglobulin, and antimicrobials. Restorative therapy includes definite surgery repair and replenishment of the immune system by use of immunomodulators, growth factors, and bone marrow transplantation. Further studies are needed to examine the usefulness of presently available drugs and experimental agents in the irradiated and traumatized host. 111 references.

  15. In-Group Versus Out-Group Source Memory.

    Science.gov (United States)

    Greenstein, Michael; Franklin, Nancy; Klug, Jessica

    2016-06-01

    A common finding in the source monitoring literature is that greater similarity impairs source discriminability. Experiments traditionally manipulate similarity overtly by describing or showing sources with explicitly differentiable features. However, people may also infer source characteristics themselves, which should also affect discriminability. Two studies examined inferred source characteristics by capitalizing on the out-group homogeneity effect, whereby in-group members are conceptualized as more diverse than out-group members. Participants learned about two sources who were described only as members of an in-group or an out-group and whose actions did not have higher a priori association with either group. Source memory was superior when participants believed the sources to be in-group members. This demonstrates that people spontaneously include inferred features with source representations and can capitalize on these features during source monitoring. Interestingly, information suggesting membership in one's in-group improved performance even for sources who had previously been considered out-group members (Experiment 2).

  16. Finite Groups with Its Power Automorphism Groups Having Small Indices

    Institute of Scientific and Technical Information of China (English)

    Jun Xin WANG; Xiu Yun GUO

    2009-01-01

    In this paper,a finite group G with|Aut(G) : P(G)| = p or pq is determined,where P(G)is the power automorphism group of G,and p,q are distinct primes.Especially,we prove that a finite group G satisfies |Aut(G) : P(G)| = pq if and only if Aut(G)/P(G) (≈)S3.Also,some other classes of finite groups are investigated and classified,which are necessary for the proof of our main results.

  17. [Group cohesion: a concept analysis].

    Science.gov (United States)

    Lin, Yen-Ru; Chen, Yu-Jung; Tzeng, Wen-Chii; Chou, Kuei-Ru

    2007-10-01

    Group cohesion is considered an essential condition for achieving a successful treatment team. High cohesion groups more readily reach their goals, with group members also feeling more secure about their functions and contributions. In clinical practice, nurses use group teaching and group therapy to help patient and family members gain knowledge and skills related to illness treatment and recuperation. Effective group leadership helps minimize non-productive time and manpower and enhance interpersonal interaction. A further advantage of group cohesion is that the more effective administration of nursing programs that results can raise the profession level of staffs and reduce turnover. Walker and Avant (1995) employ concept analysis to use defining attributes in order to apply the same definition and communication to the same profession. The purpose of this paper was to apply this methodology to an analysis of group cohesion. Steps used include a review of the literature on conceptual definitions of group cohesion, a determination of defining attributes, model construction, identification of borderline, contrary, and related cases, and identification of antecedents and consequences and empirical tools. It is hoped that this analysis can help nursing staff to gain a better understanding of the concept of group cohesion and to apply such to clinical practice and nursing administration.

  18. Duality group actions on fermions

    CERN Document Server

    Pantev, T

    2016-01-01

    In this short paper we look at the action of T-duality and string duality groups on fermions, in maximally-supersymmetric theories and related theories. Briefly, we argue that typical duality groups such as SL(2,Z) have sign ambiguities in their actions on fermions, and propose that pertinent duality groups be extended by Z_2, to groups such as the metaplectic group. Specifically, we look at duality groups arising from mapping class groups of tori in M theory compactifications, T-duality, ten-dimensional type IIB S-duality, and (briefly) four-dimensional N=4 super Yang-Mills, and in each case, propose that the full duality group is a nontrivial Z_2 extension of the duality group acting on bosonic degrees of freedom, to more accurately describe possible actions on fermions. We also walk through U-duality groups for toroidal compactifications to nine, eight, and seven dimensions, which enables us to perform cross-consistency tests of these proposals.

  19. Duality group actions on fermions

    Science.gov (United States)

    Pantev, Tony; Sharpe, Eric

    2016-11-01

    In this short paper we look at the action of T-duality and string duality groups on fermions, in maximally-supersymmetric theories and related theories. Briefly, we argue that typical duality groups such as SL(2 , ℤ) have sign ambiguities in their actions on fermions, and propose that pertinent duality groups be extended by ℤ2, to groups such as the metaplectic group. Specifically, we look at duality groups arising from mapping class groups of tori in M theory compactifications, T-duality, ten-dimensional type IIB S-duality, and (briefly) four-dimensional N = 4 super Yang-Mills, and in each case, propose that the full duality group is a nontrivial ℤ2 extension of the duality group acting on bosonic degrees of freedom, to more accurately describe possible actions on fermions. We also walk through U-duality groups for toroidal compactifications to nine, eight, and seven dimensions, which enables us to perform cross-consistency tests of these proposals.

  20. The Local Group and other neighboring galaxy groups

    CERN Document Server

    Karachentsev, I D

    2004-01-01

    Over the last few years, rapid progress has been made in distance measurements for nearby galaxies based on the magnitude of the tip of red giant branch stars. Current CCD surveys with HST and large ground- based telescopes bring $\\sim$10%-accurate distances for roughly a hundred galaxies within 5 Mpc. The new data on distances to galaxies situated in (and around) the nearest groups: the Local Group, M81 group, CenA/M83 group, IC342/Maffei group, Sculptor filament, and Canes Venatici cloud allowed us to determine their total mass from the radius of the zero- velocity surface, $R_0$, which separates a group as bound against the homogeneous cosmic expansion. The values of $R_0$ for the virialized groups turn out to be close each other, in the range of 0.9 -- 1.3 Mpc. As a result, the total masses of the groups are close to each other, too, yielding total mass-to-blue luminosity ratios of 10 -- 40 $M_{\\sun}/L_{\\sun}$. The new total mass estimates are 3 -- 5 times lower than old virial mass estimates of these gro...

  1. Good for the group? Explaining apparent group-level selection

    NARCIS (Netherlands)

    Smallegange, I.M.; Egas, M.

    2015-01-01

    The idea that group selection can explain adaptive trait evolution is still controversial. Recent empirical work proposes evidence for group-level adaptation in a social spider, but the findings can also be explained from an individual-level perspective. The challenge remains to identify situations

  2. Group lending and the role of the group leader

    NARCIS (Netherlands)

    van Eijkel, R.; Hermes, C.L.M.; Lensink, B.W.

    2011-01-01

    This paper investigates strategic monitoring behavior within group lending. We show that monitoring efforts of group members differ in equilibrium due to the asymmetry between members in terms of future profits. In particular, we show that the entrepreneur with the highest future profits also puts i

  3. Logspace Computations in Coxeter Groups and Graph Groups

    CERN Document Server

    Diekert, Volker; Lohrey, Markus

    2012-01-01

    Computing normal forms in groups (or monoids) is in general harder than solving the word problem (equality testing). However, normal form computation has a much wider range of applications. It is therefore interesting to investigate the complexity of computing normal forms for important classes of groups. For Coxeter groups we show that the following algorithmic tasks can be solved by a deterministic Turing machine using logarithmic work space, only: 1. Compute the length of any geodesic normal form. 2. Compute the set of letters occurring in any geodesic normal form. 3. Compute the Parikh-image of any geodesic normal form in case that all defining relations have even length (i.e., in even Coxeter groups.) 4. For right-angled Coxeter groups we can do actually compute the short length normal form in logspace. (Note that short length normal forms are geodesic.) Next, we apply the results to right-angled Artin groups. They are also known as free partially commutative groups or as graph groups. As a consequence o...

  4. Group Journaling: A Tool for Reflection, Fun and Group Development

    Science.gov (United States)

    Asfeldt, Morten

    2012-01-01

    Personal journaling is common practice in outdoor programs and is an important means of reflection and meaning-making. For over 20 years the author has used group journals to promote reflection and understanding, raise important questions, explore difficult issues, develop writing and speaking skills, and enhance group development. In this…

  5. Countably determined compact abelian groups

    CERN Document Server

    Dikranjan, Dikran

    2008-01-01

    For an abelian topological group G let G^* be the dual group of all continuous characters endowed with the compact open topology. A subgroup D of G determines G if the restriction homomorphism G^* --> D^* of the dual groups is a topological isomorphism. Given a scattered compact subset X of an infinite compact abelian group G such that |X|group, we show that the set of all characters which send X into U has the same size as G^*. (Here w(G) denotes the weight of G.) As an application, we prove that a compact abelian group determined by its countable subgroup must be metrizable. This gives a negative answer to questions of Comfort, Hernandez, Macario, Raczkowski and Trigos-Arrieta, as well as provides short proofs of main results established in three manuscripts by these authors.

  6. Groups, graphs and random walks

    CERN Document Server

    Salvatori, Maura; Sava-Huss, Ecaterina

    2017-01-01

    An accessible and panoramic account of the theory of random walks on groups and graphs, stressing the strong connections of the theory with other branches of mathematics, including geometric and combinatorial group theory, potential analysis, and theoretical computer science. This volume brings together original surveys and research-expository papers from renowned and leading experts, many of whom spoke at the workshop 'Groups, Graphs and Random Walks' celebrating the sixtieth birthday of Wolfgang Woess in Cortona, Italy. Topics include: growth and amenability of groups; Schrödinger operators and symbolic dynamics; ergodic theorems; Thompson's group F; Poisson boundaries; probability theory on buildings and groups of Lie type; structure trees for edge cuts in networks; and mathematical crystallography. In what is currently a fast-growing area of mathematics, this book provides an up-to-date and valuable reference for both researchers and graduate students, from which future research activities will undoubted...

  7. Group theory and its applications

    CERN Document Server

    Thapa, Ram Kumar

    2019-01-01

    Every molecule possesses symmetry and hence has symmetry operations and symmetry elements. From symmetry properties of a system we can deduce its significant physical results. Consequently it is essential to operations of a system forms a group. Group theory is an abstract mathematical tool that underlies the study of symmetry and invariance. By using the concepts of symmetry and group theory, it is possible to obtain the members of complete set of known basis functions of the various irreducible representations of the group. I practice this is achieved by applying the projection operators to linear combinations of atomic orbital (LCAO) when the valence electrons are tightly bound to the ions, to orthogonalized plane waves (OPW) when valence electrons are nearly free and to the other given functions that are judged to the particular system under consideration. In solid state physics the group theory is indispensable in the context of finding the energy bands of electrons in solids. Group theory can be applied...

  8. Group supervision for general practitioners

    DEFF Research Database (Denmark)

    Galina Nielsen, Helena; Sofie Davidsen, Annette; Dalsted, Rikke;

    2013-01-01

    AIM: Group supervision is a sparsely researched method for professional development in general practice. The aim of this study was to explore general practitioners' (GPs') experiences of the benefits of group supervision for improving the treatment of mental disorders. METHODS: One long...... considered important prerequisites for disclosing and discussing professional problems. CONCLUSION: The results of this study indicate that participation in a supervision group can be beneficial for maintaining and developing GPs' skills in dealing with patients with mental health problems. Group supervision......-established supervision group was studied closely for six months by observing the group sessions, and by interviewing GPs and their supervisors, individually and collectively. The interviews were recorded digitally and transcribed verbatim. The data were analysed using systematic text condensation. RESULTS: The GPs found...

  9. Peritonite infecciosa com quantitativos e qualitativos bacterianos conhecidos: estudo experimental em ratos Infectious peritonitis with known bacterial concentration: experimental study in rats

    Directory of Open Access Journals (Sweden)

    Gilton Ângelo Guilgen

    1998-02-01

    altas concentrações bacterianas mostraram maior perda de peso, alterações clínicas de sepsis, peritonite difusa aguda, derrame pleural e óbito precoce.This study reveals development of difuse peritonitis model in rats with a known bacterial concentration. We analised 150 rats, adults, mate, Wistar race with medium weight of 150 grams. Solutions of Escherichia coli and Bacteroides fragilis in diferent concentrations were percutaneous inoculated into the peritoneal cavity in the following proportion: 1 ml of each suspension to each 100 grams of the total weight of the rato the animals were allocated in five groups of thirty rats. On - group I (control a solution of sodium cloride 0.9%. On the following groups the proportions were as follows: group II - 10(9; group III - 10(8; group 1V -10(7 and group V - 10(6. After a rat death, a necropsy was performed in order to evaluate macroscopic effects on peritoneal cavity as well collect samples of secretions for culture. The survival rats ofeach group were subdivided with no choice in two subgroups. The animals for subgroup A were sacrificed 24 hours after inoculation and the ones of subgroup B, 120 hours after inoculation. We observed that the rats of group 1 did not acquire peritonitis. On group II and III, 100% of subgroup A and 95.03% of subgroup B, developed acute peritonitis. On group II only 4.17% developed peritonitis and died 72 hours and on group V neither peritonitis or death developed. The animals which died on group II and III on an average of 96.67% showed macroscopic alterations with difused peritoneum exudate, adherences and no abscesses. The animals which developed peritonitis exhibited bilateral pleural effusion. On animals of group II and III which died, also were found the presence of Eschirichia coli and Bacteroides fragilis responsible for peritonitis and pleural effusion. This model shows that the animal which received the highest bacterial concentrations showed loss of weight, clinical alterations

  10. Cascade Product of Permutation Groups

    OpenAIRE

    Egri-Nagy, Attila; Nehaniv, Chrystopher L.

    2013-01-01

    We define the cascade product of permutation groups as an external product, an explicit construction of substructures of the iterated wreath product that are much smaller than the full wreath product. This construction is essential for computational implementations of algebraic hierarchical decompositions of finite automata. We show how direct, semidirect, and wreath products and group extensions can all be expressed as cascade products, and analyse examples of groups that can be constructed ...

  11. Taxonomy Working Group Final Report

    Science.gov (United States)

    Parsons, Vickie S.; Beil, Robert J.; Terrone, Mark; Barth, Timothy S.; Panontin, Tina L.; Wales, Roxana; Rackley, Michael W.; Milne, James S.; McPherson, John W.; Dutra, Jayne E.; Shaw, Larry C.

    2009-01-01

    The purpose of the Taxonomy Working Group was to develop a proposal for a common taxonomy to be used by all NASA projects in the classifying of nonconformances, anomalies, and problems. Specifically, the group developed a recommended list of data elements along with general suggestions for the development of a problem reporting system to better serve NASA's need for managing, reporting, and trending project aberrant events. The Group's recommendations are reported in this document.

  12. Group Connectivity and Group Colorings of Graphs - A Survey

    Institute of Scientific and Technical Information of China (English)

    Hong-Jian LAI; Xiangwen LI; Yehong SHAO; Mingquan ZHAN

    2011-01-01

    In 1950s, Tutte introduced the theory of nowhere-zero flows as a tool to investigate the coloring problem of maps, together with his most fascinating conjectures on nowhere-zero flows. These have been extended by Jaeger et al. In 1992 to group connectivity, the nonhomogeneous form of nowhere-zero flows. Let G be a 2-edge-connected undirected graph, A be an (additive) abelian group and A* = A - {0}. The graph G is A-connected if G has an orientation D(G) such that for every each vertex v ∈ V(G), the total amount of f-values on the edges directed out from v minus the total amount of f-values on the edges directed into v is equal to b(v). The group coloring of a graph arises from the dual concept of group connectivity. There have been lots of investigations on these subjects.This survey provides a summary of researches on group connectivity and group colorings of graphs. It contains the following sections.1. Nowhere-zero Flows and Group Connectivity of Graphs 2. Complete Families and A-reductions 3. Reductions with Edge-deletions, Vertex-deletions and Vertex-splitting 4. Group Colorings as a Dual Concept of Group Connectivity 5. Brooks Theorem, Its Variations and Dual Forms 6. Planar Graphs 7. Group Connectivity of Graphs 7.1 Highly Connected Graphs and Collapsible Graphs 7.2 Degrees Conditions 7.3 Complementary Graphs 7.4 Products of Graphs 7.5 Graphs with Diameter at Most 2 7.6 Line Graphs and Claw-Free Graphs 7.7 Triangular Graphs 7.8 Claw-decompositions and All Tutte-orientations

  13. Group decision-making: Factors that affect group effectiveness

    Directory of Open Access Journals (Sweden)

    Juliana Osmani

    2016-03-01

    Full Text Available Organizations are operating in a dynamic and turbulent environment. In these conditions, they have to make decisions for new problems or situations. Most of decisions are therefore non-programmed and unstructured, accompanied by risk and uncertainty. Moreover, the problems and situations are complex. All organizations are oriented towards group decisionmaking processes, as useful tools to cope with uncertainty and complexity. Apart from the necessity, companies are turning towards participatory processes also to benefit from the important advantages that these processes offer. Organizations have realized the importance of group decision-making processes to contribute to the creation of sustainable competitive advantages. Main objective of this paper is to show that group decision-making processes do not offer guarantee for good decisions, because the effectiveness of group is affected by many factors. So, the first thing done in this paper is discussing about the benefits and limitations that accompany the use of groups with decision-making purpose. Afterwards, we stop on the different factors that influence the group’s ability to make good decisions. The aim is to emphasize that regardless of the many advantages of groups, some factors as group size, type of communication within the group, leadership style, the norms, the differentiation of roles and statuses, cohesion and compliance degree should be the main elements to keep into consideration because they affect the effectiveness of group. In this regard, is discussed how such factors influence the quality of decision and then we try to draw some conclusions that can improve and make better and easier group decision-making processes.

  14. Automorphism groups of some algebras

    Institute of Scientific and Technical Information of China (English)

    PARK; Hong; Goo; LEE; Jeongsig; CHOI; Seul; Hee; NAM; Ki-Bong

    2009-01-01

    The automorphism groups of algebras are found in many papers. Using auto-invariance, we find the automorphism groups of the Laurent extension of the polynomial ring and the quantum n-plane (respectively, twisting polynomial ring) in this work. As an application of the results of this work, we can find the automorphism group of a twisting algebra. We define a generalized Weyl algebra and show that the generalized Weyl algebra is simple. We also find the automorphism group of a generalized Weyl algebra. We show that the generalized Weyl algebra Am,m+n is the universal enveloping algebra of the generalized Witt algebra W(m,m + n).

  15. The Nearest Group of Galaxies

    CERN Document Server

    Van den Bergh, S

    1999-01-01

    The small Antlia-Sextans clustering of galaxies is located at a distance of only 1.36 Mpc from the Sun, and 1.72 Mpc from the adopted barycenter of the Local Group. The latter value is significantly greater than the radius of the zero- velocity surface of the Local Group which, for an assumed age of 14 Gyr, has Ro = 1.18 " 0.15 Mpc. This, together with the observation that the members of the Ant-Sex group have a mean redshift of +114 " 12 km s-1 relative to the centroid of the Local Group, suggests that the Antlia-Sextans group is not bound to our Local Group, and that it is expanding with the Hubble flow. If this conclusion is correct, then Antlia-Sextans may be the nearest external clustering of galaxies. The total galaxian population of the Ant-Sex group is ~ 1/5 that of the Local Group. However, the integrated luminosity of Ant-Sex is two orders of magnitude lower than that of the Local Group. Subject headings: Galaxies - clusters: individual (Antlia-Sextans)

  16. Abstract commensurators of braid groups

    OpenAIRE

    Leininger, Christopher J; Margalit, Dan

    2005-01-01

    Let B_n be the braid group on n strands, with n at least 4, and let Mod(S) be the extended mapping class group of the sphere with n+1 punctures. We show that the abstract commensurator of B_n is isomorphic to a semidirect product of Mod(S) with a group we refer to as the transvection subgroup, Tv(B_n). We also show that Tv(B_n) is itself isomorphic to a semidirect product of an infinite dimensional rational vector space with the multiplicative group of nonzero rational numbers.

  17. Automorphism groups of some algebras

    Institute of Scientific and Technical Information of China (English)

    PARK Hong Goo; LEE Jeongsig; CHOI Seul Hee; CHEN XueQing; NAM Ki-Bong

    2009-01-01

    The automorphism groups of algebras are found in many papers. Using auto-invariance, we find the automorphism groups of the Laurent extension of the polynomial ring and the quantum n-plane (respectively, twisting polynomial ring) in this work. As an application of the results of this work, we can find the automorphism group of a twisting algebra. We define a generalized Weyl algebra and show that the generalized Weyl algebra is simple. We also find the automorphism group of a generalized Weyl algebra. We show that the generalized Weyl algebra Am,m+n is the universal enveloping algebra of the generalized Witt algebra W(m, m+n).

  18. Strategic Groups and Banks’ Performance

    Directory of Open Access Journals (Sweden)

    Gregorz Halaj

    2009-06-01

    Full Text Available The theory of strategic groups predicts the existence of stable groups of companies that adopt similar business strategies. The theory also predicts that groups will differ in performance and in their reaction to external shocks. We use cluster analysis to identify strategic groups in the Polish banking sector. We find stable groups in the Polish banking sector constituted after the year 2000 following the major privatisation and ownership changes connected with transition to the mostly-privately-owned banking sector in the late 90s. Using panel regression methods we show that the allocation of banks to groups is statistically significant in explaining the profitability of banks. Thus, breaking down the banks into strategic groups and allowing for the different reaction of the groups to external shocks helps in a more accurate explanation of profits of the banking sector as a whole.Therefore, a more precise ex ante assessment of the loss absorption capabilities of banks is possible, which is crucial for an analysis of banking sector stability. However, we did not find evidence of the usefulness of strategic groups in explaining the quality of bank portfolios as measured by irregular loans over total loans, which is a more direct way to assess risks to financial stability.

  19. Twisted conjugacy in braid groups

    CERN Document Server

    González-Meneses, Juan

    2011-01-01

    In this note we solve the twisted conjugacy problem for braid groups, i.e. we propose an algorithm which, given two braids $u,v\\in B_n$ and an automorphism $\\phi \\in Aut (B_n)$, decides whether $v=(\\phi (x))^{-1}ux$ for some $x\\in B_n$. As a corollary, we deduce that each group of the form $B_n \\rtimes H$, a semidirect product of the braid group $B_n$ by a torsion-free hyperbolic group $H$, has solvable conjugacy problem.

  20. Visual Grouping by Neural Oscillators

    CERN Document Server

    Yu, Guoshen

    2008-01-01

    Distributed synchronization is known to occur at several scales in the brain, and has been suggested as playing a key functional role in perceptual grouping. State-of-the-art visual grouping algorithms, however, seem to give comparatively little attention to neural synchronization analogies. Based on the framework of concurrent synchronization of dynamic systems, simple networks of neural oscillators coupled with diffusive connections are proposed to solve visual grouping problems. Multi-layer algorithms and feedback mechanisms are also studied. The same algorithm is shown to achieve promising results on several classical visual grouping problems, including point clustering, contour integration and image segmentation.

  1. Membership Rules - LHCRRB Scrutiny Group

    CERN Document Server

    2017-01-01

    The LHC Resources Scrutiny Group was created in 2001 to review and scrutinize the M&O cost estimates of the LHC Collaborations. The Scrutiny Group first met on 23 August 2001 and reported to the RRBs at its 13th Plenary meeting, in October 2001 (RRB-D-2001-8). The Scrutiny Group operates according to the procedures set out in Annex 12 of the MoUs for the M&O of the LHC experiments. This document lists the Rules of Procedure that apply to the M&O Scrutiny Group

  2. Stick with your group: young children's attitudes about group loyalty.

    Science.gov (United States)

    Misch, Antonia; Over, Harriet; Carpenter, Malinda

    2014-10-01

    For adults, loyalty to the group is highly valued, yet little is known about how children evaluate loyalty. We investigated children's attitudes about loyalty in a third-party context. In the first experiment, 4- and 5-year-olds watched a video of two groups competing. Two members of the losing group then spoke. The disloyal individual said she wanted to win and therefore would join the other group. The loyal individual said she also wanted to win but would stay with her group. Children were then asked five forced-choice questions about these two individuals' niceness, trustworthiness, morality, and deservingness of a reward. The 5-year-olds preferred the loyal person across all questions; results for the 4-year-olds were considerably weaker but in the same direction. The second experiment investigated the direction of the effect in 5-year-olds. In this experiment, children answered questions about either a loyal individual, a disloyal individual, or a neutral individual. Children rated both the loyal and neutral individuals more positively than the disloyal individual across a number of measures. Thus, whereas disloyal behavior is evaluated unfavorably by children, loyal behavior is the expected norm. These results suggest that, at least from 5 years of age, children understand that belonging to a group entails certain commitments. This marks an important step in their own ability to negotiate belonging and become trustworthy and reliable members of their social groups.

  3. Commensal Bacteria-Induced Inflammasome Activation in Mouse and Human Macrophages Is Dependent on Potassium Efflux but Does Not Require Phagocytosis or Bacterial Viability

    Science.gov (United States)

    Chen, Kejie; Shanmugam, Nanda Kumar N.; Pazos, Michael A.; Hurley, Bryan P.; Cherayil, Bobby J.

    2016-01-01

    Gut commensal bacteria contribute to the pathogenesis of inflammatory bowel disease, in part by activating the inflammasome and inducing secretion of interleukin-1ß (IL-1ß). Although much has been learned about inflammasome activation by bacterial pathogens, little is known about how commensals carry out this process. Accordingly, we investigated the mechanism of inflammasome activation by representative commensal bacteria, the Gram-positive Bifidobacterium longum subspecies infantis and the Gram-negative Bacteroides fragilis. B. infantis and B. fragilis induced IL-1ß secretion by primary mouse bone marrow-derived macrophages after overnight incubation. IL-1ß secretion also occurred in response to heat-killed bacteria and was only partly reduced when phagocytosis was inhibited with cytochalasin D. Similar results were obtained with a wild-type immortalized mouse macrophage cell line but neither B. infantis nor B. fragilis induced IL-1ß secretion in a mouse macrophage line lacking the nucleotide-binding/leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome. IL-1ß secretion in response to B. infantis and B. fragilis was significantly reduced when the wild-type macrophage line was treated with inhibitors of potassium efflux, either increased extracellular potassium concentrations or the channel blocker ruthenium red. Both live and heat-killed B. infantis and B. fragilis also induced IL-1ß secretion by human macrophages (differentiated THP-1 cells or primary monocyte-derived macrophages) after 4 hours of infection, and the secretion was inhibited by raised extracellular potassium and ruthenium red but not by cytochalasin D. Taken together, our findings indicate that the commensal bacteria B. infantis and B. fragilis activate the NLRP3 inflammasome in both mouse and human macrophages by a mechanism that involves potassium efflux and that does not require bacterial viability or phagocytosis. PMID:27505062

  4. Energy Innovation. IVO group`s research and development report

    Energy Technology Data Exchange (ETDEWEB)

    Salminen, P.; Laiho, Y.; Kaikkonen, H.; Leisio, C.; Hinkkanen, S.; Fletcher, R. [eds.

    1997-11-01

    This annual booklet of the IVO Group`s research and development activities presents a number of articles, written by experts from IVO. The products described are examples of the environmentally-oriented selection made available by the IVO Group. In fact, the entire energy technology developed in Finland is environmentally oriented, if seen from the international perspective. The new business potential of environmental technology is great, and it is believed that in the year 2000, exportation of Finnish know-how in the field of energy-saving and efficiency will exceed the value of out energy imports

  5. 2002 annual report EDF group; 2002 rapport annuel groupe EDF

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document is the 2002 annual report of Electricite de France (EdF) group, the French electric utility. Content: Introductory section (EDF at a glance, Chairman's message, 2002 Highlights); Corporate governance and Group strategy (Corporate governance, sustainable growth strategy, EDF branches); Financial performance (Reaching critical mass, Margins holding up well, Balance sheet); Human resources (Launching Group-wide synergies, Optimising human resources); Customers (Major customers, SMEs and professional customers, Local authorities, Residential customers, Ensuring quality access to electricity); Generation (A balanced energy mix, Nuclear generation, Fossil-fuelled generation, Renewable energies); Corporate social responsibility (Global and local partnerships, Promoting community development)

  6. Energy Innovation. IVO Group`s Research and Development Report

    Energy Technology Data Exchange (ETDEWEB)

    Salminen, P.; Laiho, Y.; Kaikkonen, H.; Leisio, C.; Hinkkanen, S. [eds.

    1996-11-01

    This annual booklet of the IVO Group`s research and development activities presents a number of articles, written by experts from IVO. The products described are examples of the environmentally-oriented selection made available by the IVO Group. In fact, the entire energy technology developed in Finland is environmentally oriented, if seen from the international perspective. The new business potential of environmental technology is great, and it is believed that in the year 2000, exportation of Finnish know-how in the field of energy-saving and efficiency will exceed the value of out energy imports

  7. Working group report: Quantum chromodynamics

    Indian Academy of Sciences (India)

    V Ravindra; Pankaj Agrawal; Rahul Basu; Satyaki Bhattacharya; J Blümlein; V Del Duca; R Harlander; D Kosower; Prakash Mathews; Anurag Tripathi

    2006-11-01

    This is the report of the subgroup QCD of Working Group-4 at WHEPP-9. We present the activities that had taken place in the subgroup and report some of the partial results arrived at following the discussion at the working group meetings.

  8. Group theoretical methods in Physics

    Energy Technology Data Exchange (ETDEWEB)

    Olmo, M.A. del; Santander, M.; Mateos Guilarte, J.M. (eds.) (Universidad de Valladolid. Facultad de Ciencias. Valladolid (Spain))

    1993-01-01

    The meeting had 102 papers. These was distributed in following areas: -Quantum groups,-Integrable systems,-Physical Applications of Group Theory,-Mathematical Results,-Geometry, Topology and Quantum Field Theory,-Super physics,-Super mathematics,-Atomic, Molecular and Condensed Matter Physics. Nuclear and Particle Physics,-Symmetry and Foundations of classical and Quantum mechanics.

  9. Measuring group climate in prison

    NARCIS (Netherlands)

    van der Helm, P.; Stams, G.J.; van der Laan, P.

    2011-01-01

    The present study examines the construct validity and reliability of the Prison Group Climate Instrument (PGCI) in a sample of 77 adolescents placed in a Dutch youth prison and 49 adult prisoners living in a Dutch psychiatric prison with a therapeutic living group structure. Confirmatory factor anal

  10. Group Work in Science Classrooms

    Science.gov (United States)

    McGregor, Debbie; Tolmie, Andrew

    2009-01-01

    This article considers how students might work together in small groups, from two to eight, in either a primary or secondary science classroom. The nature of group work can vary widely and could include, for example, a pair carrying out an illustrative experiment, a trio or quad debating climate change, or six or seven rehearsing how they will…

  11. Exploring Interpersonal Compatibility in Groups.

    Science.gov (United States)

    Keyton, Joann

    This study investigated William Schutz's three-dimensional theory of interpersonal behavior and compatibility (FIRO) to determine its validity as a group measure of compatibility. Data were collected from 248 students enrolled in a multi-section course in small group communications at a large midwestern university. Subjects self-selected…

  12. Group Intervention in Pediatric Rehabilitation

    Science.gov (United States)

    LaForme Fiss, Alyssa

    2012-01-01

    Group intervention in pediatric physical and occupational therapy is an alternative to individual intervention allowing the therapist to meet the needs of multiple children at one time. Survey research indicates that approximately 40% to 60% of pediatric physical and occupational therapists use group intervention at least occasionally in practice,…

  13. The Globalization of Cooperative Groups.

    Science.gov (United States)

    Valdivieso, Manuel; Corn, Benjamin W; Dancey, Janet E; Wickerham, D Lawrence; Horvath, L Elise; Perez, Edith A; Urton, Alison; Cronin, Walter M; Field, Erica; Lackey, Evonne; Blanke, Charles D

    2015-10-01

    The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future.

  14. Modeling Interactions in Small Groups

    Science.gov (United States)

    Heise, David R.

    2013-01-01

    A new theory of interaction within small groups posits that group members initiate actions when tension mounts between the affective meanings of their situational identities and impressions produced by recent events. Actors choose partners and behaviors so as to reduce the tensions. A computer model based on this theory, incorporating reciprocal…

  15. Topological dynamics and definable groups

    CERN Document Server

    Pillay, Anand

    2012-01-01

    Following the works of Newelski we continue the study of the relations between abstract topological dynamics and generalized stable group theory. We show that the Ellis theory, applied to the action of G(M) on its type space, for G an fsg group in a NIP theory, and M any model, yields the quotient G/G^00.

  16. Second Anthropocene Working Group meeting

    OpenAIRE

    2016-01-01

    The second meeting of the Anthropocene Working Group (AWG) was held at the McDonald Institute for Archaeological Research, University of Cambridge, on 24th and 25th November 2015. It took the form of a workshop with 12 members of the working group and numerous archaeologists from the Institute in lively conversation with each other. Dis...

  17. Social Disaffection Among Deprived Groups

    Science.gov (United States)

    Katz, Daniel; And Others

    1977-01-01

    Examines groups of individuals of differing income, education, occupation, age and sex and investigates the extent of differences between these groups on three levels: nationalism, support for the political system and satisfaction with aspects of every day living. Available from: International Journal of Intercultural Relations, Transaction…

  18. Loop groups and noncommutative geometry

    CERN Document Server

    Carpi, Sebastiano

    2015-01-01

    We describe the representation theory of loop groups in terms of K-theory and noncommutative geometry. This is done by constructing suitable spectral triples associated with the level l projective unitary positive-energy representations of any given loop group LG. The construction is based on certain supersymmetric conformal field theory models associated with LG.

  19. Working Group VII: Food Products

    OpenAIRE

    Midtvedt, Tore

    2011-01-01

    The working group recognised that many international and national organisations had developed strategies for evaluating the safety of new food products produced by the application of genetic modification. These strategies were necessarily fairly general and the group agreed that it should focus its attention on the pathogenicity and toxicity of live microorganisms used in food.

  20. Challenges Facing Group Work Online

    Science.gov (United States)

    Chang, Bo; Kang, Haijun

    2016-01-01

    Online group work can be complicated because of its asynchronous characteristics and lack of physical presence, and its requirements for skills in handling technology, human relationships, and content-related tasks. This study focuses on the administrative, logistical and relationship-related challenges in online group work. Challenges in areas…