for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> BIOLOGY (Total: 2541 journals)
    - BIOCHEMISTRY (188 journals)
    - BIOENGINEERING (55 journals)
    - BIOLOGY (1298 journals)
    - BIOPHYSICS (41 journals)
    - BIOTECHNOLOGY (144 journals)
    - BOTANY (188 journals)
    - CYTOLOGY AND HISTOLOGY (25 journals)
    - ENTOMOLOGY (50 journals)
    - GENETICS (136 journals)
    - MICROBIOLOGY (200 journals)
    - MICROSCOPY (9 journals)
    - ORNITHOLOGY (23 journals)
    - PHYSIOLOGY (66 journals)
    - ZOOLOGY (118 journals)

BIOLOGY (1298 journals)            First | 1 2 3 4 5 6 7 8 | Last

EJNMMI Research     Open Access   (1 follower)
Electromagnetic Biology and Medicine     Hybrid Journal   (2 followers)
eLife     Open Access   (10 followers)
el–Hayah     Open Access   (1 follower)
Embo Molecular Medicine     Open Access   (3 followers)
EMBO reports     Full-text available via subscription   (13 followers)
Emotion Review     Hybrid Journal   (9 followers)
Endocrine Connections     Open Access   (2 followers)
Engineering & Technology     Hybrid Journal   (15 followers)
Engineering Economist, The     Hybrid Journal   (3 followers)
Engineering in Life Sciences     Hybrid Journal   (3 followers)
Engineering Optimization     Hybrid Journal   (5 followers)
Ensaios e Ciência: Ciências Biológicas, Agrárias e da Saúde     Open Access  
Environmental Biology of Fishes     Hybrid Journal   (3 followers)
Environmental Biosafety Research     Hybrid Journal   (1 follower)
Environmental Microbiology     Hybrid Journal   (5 followers)
Environmental Science & Technology     Full-text available via subscription   (156 followers)
Enzyme and Microbial Technology     Hybrid Journal   (5 followers)
Epidemiology & Infection     Hybrid Journal   (11 followers)
ESHRE Monographs     Hybrid Journal  
Ethiopian Journal of Biological Sciences     Open Access   (1 follower)
Ethnobiology and Conservation     Open Access   (2 followers)
Ethnobotany Research & Applications : a journal of plants, people and applied research     Open Access   (5 followers)
Ethology     Hybrid Journal   (2 followers)
Ethology Ecology & Evolution     Hybrid Journal   (7 followers)
Eukaryotic Cell     Full-text available via subscription   (6 followers)
EuPA Open Proteomics     Open Access   (1 follower)
EURASIP Journal on Bioinformatics and Systems Biology     Open Access   (6 followers)
European Journal of Cell Biology     Hybrid Journal   (3 followers)
European Journal of Neuroscience     Hybrid Journal   (19 followers)
European Journal of Phycology     Hybrid Journal   (5 followers)
European Journal of Protistology     Hybrid Journal   (2 followers)
European Journal of Soil Biology     Hybrid Journal   (1 follower)
European Journal of Wood and Wood Products     Hybrid Journal   (3 followers)
European Online Journal of Natural and Social Sciences     Open Access   (10 followers)
European Scientific Journal     Open Access   (1 follower)
Evidência - Ciência e Biotecnologia - Interdisciplinar     Open Access  
EvoDevo     Open Access   (1 follower)
Evolução e Conservação da Biodiversidade     Open Access  
Evolution     Partially Free   (48 followers)
Evolution and Human Behavior     Hybrid Journal   (8 followers)
Evolutionary Applications     Open Access   (2 followers)
Evolutionary Bioinformatics     Open Access   (14 followers)
Evolutionary Biology     Hybrid Journal   (13 followers)
Evolutionary Computation     Hybrid Journal   (9 followers)
Experimental & Molecular Medicine     Open Access   (2 followers)
Experimental and Applied Acarology     Hybrid Journal   (1 follower)
Experimental Cell Research     Hybrid Journal   (3 followers)
Expert Opinion on Biological Therapy     Hybrid Journal   (10 followers)
Expert Opinion on Environmental Biology     Partially Free  
Expert Review of Proteomics     Full-text available via subscription   (2 followers)
Extreme Life, Biospeology & Astrobiology - International Journal of the Bioflux Society     Full-text available via subscription   (2 followers)
Extremophiles     Hybrid Journal  
F1000Research     Open Access   (3 followers)
Familial Cancer     Hybrid Journal   (1 follower)
Fatigue & Fracture of Engineering Materials and Structures     Hybrid Journal   (12 followers)
Fauna Norvegica     Open Access  
Febs Journal     Hybrid Journal   (8 followers)
Feddes Repertorium     Hybrid Journal  
Fems Yeast Research     Hybrid Journal   (8 followers)
Field Mycology     Full-text available via subscription   (1 follower)
Fish & Shellfish Immunology     Hybrid Journal   (5 followers)
Fitoterapia     Hybrid Journal   (4 followers)
Fly     Full-text available via subscription  
Folia Biologica     Full-text available via subscription  
Folia Biologica et Oecologica     Open Access   (1 follower)
Folia Malacologica     Open Access  
Folia Microbiologica     Hybrid Journal   (1 follower)
Folia Primatologica     Full-text available via subscription   (1 follower)
Food and Bioproducts Processing     Hybrid Journal   (1 follower)
Forest Pathology     Hybrid Journal   (1 follower)
Forschung     Hybrid Journal  
Foundations of Physics     Hybrid Journal   (1 follower)
Free Radical Biology and Medicine     Hybrid Journal   (4 followers)
Free Radical Research     Hybrid Journal   (2 followers)
Freshwater Reviews     Full-text available via subscription   (3 followers)
Freshwater Science     Full-text available via subscription   (6 followers)
Frontiers in Ecology and Evolution     Open Access   (2 followers)
Frontiers in Life Science     Hybrid Journal  
Frontiers in Marine Science     Open Access  
Frontiers of Biogeography     Open Access   (1 follower)
Frontiers of Biology     Hybrid Journal   (1 follower)
Frontiers of Environmental Science & Engineering     Hybrid Journal   (3 followers)
Fruits     Full-text available via subscription  
Functional & Integrative Genomics     Hybrid Journal   (5 followers)
Fundamental and Applied Limnology / Archiv für Hydrobiologie     Full-text available via subscription   (1 follower)
Fungal Biology     Hybrid Journal   (4 followers)
Fungal Biology Reviews     Full-text available via subscription   (4 followers)
Fungal Diversity     Hybrid Journal   (2 followers)
Fungal Ecology     Hybrid Journal   (4 followers)
Galemys : Spanish Journal of Mammalogy     Open Access  
Gayana (Concepcion)     Open Access  
Gcb Bioenergy     Hybrid Journal   (1 follower)
Gene     Hybrid Journal   (7 followers)
Genes To Cells     Hybrid Journal   (1 follower)
Genetic Resources and Crop Evolution     Hybrid Journal   (8 followers)
Genome     Full-text available via subscription   (3 followers)
Genome Biology     Full-text available via subscription   (14 followers)
Genome Biology and Evolution     Open Access   (7 followers)
Genome Research     Full-text available via subscription   (22 followers)

  First | 1 2 3 4 5 6 7 8 | Last

Anaerobe    [6 followers]  Follow    
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1075-9964 - ISSN (Online) 1095-8274
     Published by Elsevier Homepage  [2556 journals]   [SJR: 0.828]   [H-I: 39]
  • The role of the humoral immune response to Clostridium difficile toxins A
           and B in susceptibility to Clostridium difficile Infection: a case-control
           study
    • Abstract: Publication date: Available online 5 April 2014
      Source:Anaerobe
      Author(s): J. Islam , A.L. Taylor , K. .Rao , G. Huffnagle , V.B. Young , C. Rajkumar , J. Cohen , P. Papatheodorou , D.M. Aronoff , M.J. Llewelyn
      Antibody levels to Clostridium difficile toxin A (TcdA), but not toxin B (TcdB), have been found to determine risk of C. difficile infection (CDI). Historically, TcdA was thought to be the key virulence factor; however the importance of TcdB in disease is now established. We re-evaluated the role of antibodies to TcdA and TcdB in determining patient susceptibility to CDI in two separate patient cohorts. In contrast to earlier studies, we find that CDI patients have lower pre-existing IgA titres to TcdB, but not TcdA, when compared to control patients. Our findings suggest that mucosal immunity to TcdB may be important in the early stages of infection and identifies a possible target for preventing CDI progression.


      PubDate: 2014-04-09T03:13:57Z
       
  • Antimicrobial and anti-inflammatory properties of nostocionone isolated
           from Nostoc commune Vauch and its derivatives against Propionibacterium
           acnes
    • Abstract: Publication date: Available online 1 April 2014
      Source:Anaerobe
      Author(s): Tomohiro Itoh , Akihiro Tsuchida , Yuji Muramatsu , Masayuki Ninomiya , Masashi Ando , Yasuyuki Tsukamasa , Mamoru Koketsu
      Propionibacterium acnes is the primary pathogenic agent responsible for acne vulgaris on the skin and hair follicles. Overgrowth of this bacterium inhibits growth and promotes follicular inflammation, with an associated increase in pro-inflammatory cytokine production. P. acnes has therefore been considered the main target for the prevention and medical treatment of acne vulgaris. The aim of this study was to evaluate the in vitro anti-P. acnes and anti-inflammatory properties of 6 compounds isolated from Nostoc commune. One of these compounds, nostocionone (Nost), and one of its derivatives, NostD3 [(1E,4E)-1-(3,4-dihydroxyphenyl)-5-(2,6,6-trimethylcyclohex-1-enyl)penta-1,4-dien-3-one], significantly inhibited P. acnes growth. Furthermore, we investigated the effects of Nost and NostD3 on heat-killed (hk) P. acnes-induced inflammation in macrophages. Both Nost and NostD3 suppressed hk P. acnes-induced nitric oxide (NO) production through the suppression of inducible NO synthase expression, following inactivation of nuclear factor kappa B. Taken together, our findings suggested that both Nost and NostD3 were promising agents for the treatment of acne vulgaris, and that NostD3 showed higher efficacy than Nost.
      Graphical abstract image

      PubDate: 2014-04-04T11:05:49Z
       
  • Early infection of hip joint prosthesis by Clostridium difficile in an
           HIV-1 infected patient
    • Abstract: Publication date: Available online 4 April 2014
      Source:Anaerobe
      Author(s): L. Brassinne , H. Rodriguez-Villalobos , S. Jonckheere , J.E. Dubuc , J.C. Yombi
      Anaerobes are less frequently described as causative pathogen of prosthetic joint infection (PJI). We report the first case of early PJI after hip arthroplasty due to Clostridium difficile in a diabetic and HIV-1 infected patient with bacteremia. Our patient was successfully treated through surgical debridement and prosthesis retention combined with targeted antibiotic therapy.


      PubDate: 2014-04-04T11:05:49Z
       
  • An in vitro study of the effect of probiotics, prebiotics and synbiotics
           on the elderly faecal microbiota
    • Abstract: Publication date: Available online 28 March 2014
      Source:Anaerobe
      Author(s): Eleni Likotrafiti , Kieran M. Tuohy , Glenn R. Gibson , Robert A. Rastall
      The use of dietary intervention in the elderly in order to beneficially modulate their gut microbiota has not been extensively studied. The influence of two probiotics (Bifidobacterium longum and Lactobacillus fermentum) and two prebiotics [isomaltooligosaccharides (IMO) and short-chain fructooligosaccharides (FOS)], individually and in synbiotic combinations (B. longum with IMO, L. fermentum with FOS) on the gut microbiota of elderly individuals was investigated using faecal batch cultures and three-stage continuous culture systems. Population changes of major bacterial groups were enumerated using fluorescent in situ hybridisation (FISH). B. longum and IMO alone significantly increased the Bifidobacterium count after 5 and 10 h of fermentation and their synbiotic combination significantly decreased the Bacteroides count after 5 h of fermentation. L. fermentum and FOS alone significantly increased the Bifidobacterium count after 10 h and 5, 10 and 24 h of fermentation respectively. B. longum with IMO as well as B. longum and IMO alone significantly increased acetic acid concentration during the fermentation in batch cultures. In the three stage continuous culture systems, both synbiotic combinations increased the Bifidobacterium and Lactobacillus count in the third vessel representing the distal colon. In addition, the synbiotic combination of L. fermentum with scFOS resulted in a significant increase in the concentration of acetic acid. The results show that the elderly gut microbiota can be modulated in vitro with the appropriate pro-, pre- and synbiotics.


      PubDate: 2014-03-29T12:00:22Z
       
  • pH and bacterial profile of dental plaque in children and adults of a low
           caries population
    • Abstract: Publication date: Available online 28 March 2014
      Source:Anaerobe
      Author(s): Elisabeth Raner , Lina Lindqvist , Sofia Johansson , Haidar Hassan , Anette Carlén , Narong Suksu-art , Gunnar Dahlén
      Objective This study compares pH and microbiological profile of dental plaque in children and adults of a low caries population. Material and Methods Thirty-nine children, 12-14 years of age and 45 adults between 20-39 years of age in 5 Karen villages of the Tak province, Northern Thailand were examined for plaque, calculus, caries (DMFT) and pH measurements in resting plaque and after a sucrose rinse. Information on dietary and oral hygiene habits was obtained through interviews using a fixed questionnaire. Microbiological profile of plaque samples was analyzed with DNA-DNA checkerboard technique. Results Mean DMFT was 0.77 +/- 1.56 and 87% of the adults and 67% of the children were caries free (p<0.05). The mean resting pH was for both age groups in the range of 7.0-7.1 and significantly higher than a Swedish caries free reference group. Karen adult men had significantly lower pH minimum than females and children (p<0.05). Supragingival plaque samples showed high levels of low acidogenic and anaerobic species, which dominated over strong acid producers such as streptococci. Conclusion The study indicates that the Karen children and adults has a plaque physiology and microbiology predominating by low acidogenic anaerobes, which in addition to the low sucrose intake explains the low caries prevalence in this population.


      PubDate: 2014-03-29T12:00:22Z
       
  • Identification of pili on the surface of Finegoldia magna – a
           Gram-positive anaerobic cocci
    • Abstract: Publication date: Available online 29 March 2014
      Source:Anaerobe
      Author(s): Elizabeth C. Murphy , Robert Janulczyk , Christofer Karlsson , Matthias Mörgelin , Inga-Maria Frick
      Pili have only been discovered in the major Gram-positive pathogens in the past decade and they have been found to play an important role in colonisation and virulence. Pili have been shown to have many important functions including attachment to host tissues, mediating bacterial aggregation, biofilm formation and binding to proteins in the extracellular matrix. In this study, sortase-dependent pili have been found to be expressed on the surface of Finegoldia magna ALB8. F. magna is a Gram-positive anaerobic coccus that, primarily, is a commensal of the skin and mucous membranes, but has also been isolated from various clinical infection sites and is associated with soft-tissue abscesses, wound infections and bone and prosthetic joint infections. In this study, F. magna ALB8 was found to harbor three sortases at the pilus locus, two of which bear high similarity to class C sortases in Streptococcus pneumoniae. Two putative sortase-dependent pili proteins were found in the locus, with one being identified as the major pilus subunit, Fmp1 (F. magna pilus subunit 1), due to its high similarity to other major pilus proteins in prominent Gram-positive pathogens. The presence of sortase-dependent pili was confirmed experimentally through recombinant production of Fmp1 and production of antiserum. The Fmp1 antiserum was used in Western blot to show the presence of a high molecular weight protein ladder, characteristic of the presence of pili, in trypsin released cell wall surface proteins from F. magna. The presence of sortase-dependent pili was visually confirmed by transmission electron microscopy, which showed the binding of gold labelled anti-Fmp1 to individual pilus proteins along the pilus. Furthermore, pili could also be found to bind and interact with keratinocytes in the epidermal layer of human skin, suggesting an adhesive role for pili on F. magna. Our work represents the first description of pilus structures in F. magna. This discovery further elucidates F. magna physiology and allows for additional analysis of host-bacterial interactions in future studies.


      PubDate: 2014-03-29T12:00:22Z
       
  • Validation of candidate reference genes in Bifidobacterium adolescentis
           for gene expression normalization
    • Abstract: Publication date: Available online 19 March 2014
      Source:Anaerobe
      Author(s): Verena Stenico , Loredana Baffoni , Francesca Gaggìa , Bruno Biavati
      Normalization is an essential prerequisite for producing accurate real-time PCR expression analyses. The objective of this study is the selection of a set of optimal reference genes in Bifidobacterium adolescentis gene expression studies under bile exposure. Bifidobacterium adolescentis is a particularly abundant species in the human adults gut microbiota, exerting relevant probiotic activities. In the gastrointestinal tract, bile represents a hard challenge for bacterial survival, because of its toxic effect. The natural exposure to bile in the colonic environment induces cells adaptation and tolerance mechanisms in bifidobacteria, which determines changes in gene expression profile, influencing the expression levels of housekeeping genes. In this context, the stability of 9 putative reference genes (cysS, purB, recA, rpoB-L, GADPH-R, 16S rRNA, glnA1, gyrA2, sdhA) was examined in B. adolescentis exposed to bile extract, using two different software (BestKeeper and NormFinder). Both algorithms identified gyrA2 and sdhA as the most stable genes under our experimental conditions, while 16S rRNA is the least reliable HKGs. To our best knowledge, this is the first attempt to validate reference genes in Bifidobacterium spp. and the results offer an appropriate set of reference genes suitable for qRT-PCR studies on Bifidobacterium adolescentis strains under bile stress.


      PubDate: 2014-03-19T21:25:44Z
       
  • Investigation of potentially pathogenic Clostridium difficile
           contamination in household environs
    • Abstract: Publication date: Available online 19 March 2014
      Source:Anaerobe
      Author(s): M. Jahangir Alam , Ananna Anu , Seth T. Walk , Kevin W. Garey
      As Clostridium difficile spores are resistant to many household cleaning products, the potential for community household contamination is high. The purpose of this study was to assess the prevalence of toxigenic C. difficile from environmental sources from a large urban area.Three to 5 household items or environmental dust was collected from 30 houses in Houston, Texas. A total of 127 environmental samples were collected from shoe bottoms (n=63), bathroom surfaces (n=15), house floor dusts(n=12), or other household surfaces (n=37). Forty one of 127 samples (32.3%) grew C. difficile. All 41 isolates were positive for toxin A and B genes and no isolate was positive for binary toxin genes. Shoe bottom swab samples had the highest percent of positive samples (25/63; 39.7%) followed by bathroom/toilet surfaces (5/15; 33.3%), house floor dust (4/12; 33.3%), and other surface swabs (7/37; 18.9%). Strains were grouped into 25 different ribotypes, the most prevalent type was 001 (5 strains). In conclusion, a high rate of environmental contamination of C. difficile was observed from community households from a large urban area.


      PubDate: 2014-03-19T21:25:44Z
       
  • Peritonitis caused by Bifidobacterium longum: case report and literature
           review
    • Abstract: Publication date: Available online 19 March 2014
      Source:Anaerobe
      Author(s): Daniel Tena , Cristina Losa , María José Medina , Juan Antonio Sáez-Nieto
      Bifidobacterium spp. rarely causes human infections. We report a case of a 42-year-old man with a history of pancolonic diverticulosis, who suffered a purulent peritonitis caused by Bifidobacterium longum secondary to intestinal perforation. Clinical outcome was good after urgent surgery and antibiotic treatment with imipenem and amoxicillin/clavulanic acid. Our case shows that Bifidobacterium spp. should be considered as a cause of peritonitis, especially in patients with risk of intestinal perforation. The review of the literature shows that these organisms can cause a wide spectrum of severe infections, especially in patients with underlying diseases. Infections caused by Bifidobacterium spp. may be overlooked or underreported since it may be considered normal microbiota


      PubDate: 2014-03-19T21:25:44Z
       
  • Purification and characterization of bacteriocin produced by oral
           Lactobacillus paracasei SD1
    • Abstract: Publication date: Available online 15 March 2014
      Source:Anaerobe
      Author(s): P. Wannun , S. Piwat , R. Teanpaisan
      The present study aimed to purify and characterize the antimicrobial protein from Lactobacillus paracasei SD1, which is a strain from the human oral cavity. Antimicrobial activity was obtained from purifying the culture supernatant of L. paracasei SD1. Purification of the active compound was achieved with ammonium sulfate precipitation followed by chloroform and gel filtration chromatography. As revealed by SDS-PAGE, the active fraction was homogeneous, showing a protein with an approximate molecular weight of 25,000 Da. It was confirmed as having a molecular mass of 24,028.8 Da by mass spectrometry. The antimicrobial compound, named “paracasin SD1”, exhibited a broad spectrum against oral pathogens. Paracasin SD1 was stable in a pH range between 3.0 and 8.0 at 100 °C for 5 min, and showed resistance to α-amylase, catalase, lysozyme and whole saliva. However, its activity was lost after proteinase K and trypsin treatment. The results obtained suggest the possibility of using paracasin SD1 for application in prevention/treatment of oral diseases.


      PubDate: 2014-03-19T21:25:44Z
       
  • Lactobacillus pentosus var. plantarum C29 ameliorates memory impairment
           and inflammaging in a d-galactose-induced accelerated aging mouse model
    • Abstract: Publication date: Available online 19 March 2014
      Source:Anaerobe
      Author(s): Jae-Yeon Woo , Wan Gu , Kyung-Ah Kim , Se-Eun Jang , Myung Joo Han , Dong-Hyun Kim
      Aging is associated with Alzheimer’s disease (AD), cardiovascular disease and cancer. Oxidative stress is considered a major factor that accelerates the aging process. To understand the ability of lactic acid bacteria to ameliorate memory impairment caused by aging, we investigated the effect of Lactobacillus pentosus var. plantarum (C29), which is known to protect against scopolamine-induced memory impairment, on oxidative stress ( d -galactose)-induced memory impairment in mice. d -Galactose was subcutaneously injected to 20-week old male C57BL/6J mice for 10 weeks, with oral administration of C29 for the final 5 weeks. Excessive intake of d -galactose not only impaired memory, which was indicated by passive avoidance, Y-maze, and Morris water-maze tasks, but also reduced the expression of brain-derived neurotrophic factor (BDNF) and hippocampal doublecortin (DCX) and the activation of cAMP response element-binding protein (CREB). C29 treatment ameliorated d -galactose-induced memory impairment and reversed the suppression of BDNF and DCX expression and CREB activation. Moreover, C29 decreased the expression of a senescence marker p16 and inflammation markers p-p65, p-FOXO3a, cyclooxygenase (COX)-2, and inducible NO synthase (iNOS). C29 treatment inhibited d -galactose-induced expression of M1 polarization markers tumor necrosis factor-α and arginase 2, and attenuated the d -galactose-suppressed expression of M2 markers IL-10, arginase 1 and CD206. Taken together, these findings suggest that C29 may ameliorate memory impairment and M1 macrophage-polarized inflammation caused by aging.


      PubDate: 2014-03-19T21:25:44Z
       
  • Fournier´s gangrene caused by Actinomyces funkei, Fusobacterium
           gonidiaformans and Clostridium hathewayi
    • Abstract: Publication date: Available online 13 March 2014
      Source:Anaerobe
      Author(s): Daniel Tena , Cristina Losa , María José Medina-Pascual , Juan Antonio Sáez-Nieto
      We report the first case of Fournier´s gangrene caused by three unusual anaerobic organisms: Actinomyces funkei, Fusobacterium gonidiaformans and Clostridium hathewayi. The infection occurred in a 73-year-old man without typical risk factors for the development of Fournier´s gangrene. Clinical outcome was good after prolonged antibiotic treatment and extensive debridement of the perineum. The case suggests that A. funkei, F. gonidiaformans and C. hathewayi should be considered as potential pathogens of Fournier´s gangrene. Human infections caused by these organisms are very rare but can be underestimated because correct identification is very difficult, especially in polymicrobial infections such as Fournier´s gangrene.


      PubDate: 2014-03-14T21:12:16Z
       
  • Editorial board
    • Abstract: Publication date: April 2014
      Source:Anaerobe, Volume 26




      PubDate: 2014-03-05T00:43:08Z
       
  • Effect Of Estradiol On Planktonic Growth, Coaggregation, And Biofilm
           Formation Of The Prevotella Intermedia Group Bacteria
    • Abstract: Publication date: Available online 1 March 2014
      Source:Anaerobe
      Author(s): Dareen Fteita , Eija Könönen , Eva Söderling , Ulvi Kahraman Gürsoy
      Alterations in the quantity and quality of biofilms at gingival margin are considered to play a role in the initiation and development of pregnancy-related gingivitis. Prevotella intermedia sensu lato is able to consume estradiol, the major sex hormone secreted during pregnancy, in the absence of vitamin K. The aim of the study was to examine the effect of estradiol on the planktonic growth, coaggregation, polysaccharide production, and biofilm formation of the P. intermedia group bacteria, namely P. intermedia, Prevotella nigrescens, and Prevotella pallens. In all experiments, the type strain (ATCC) and a clinical strain (AHN) of P. intermedia, P. nigrescens, and P. pallens were incubated with the concentrations of 0, 30, 90, and 120 nmol/L of estradiol. Planktonic growth was assessed by means of the colony forming unit method, while coaggregation and biofilm formation were assessed by spectrophotometric methods. In the determination of protein and polysaccharide levels, the Bradford and phenol-sulfuric acid methods were used, respectively. P. pallens AHN 9283 and P. nigrescens ATCC 33263 increased their numbers at planktonic stage with increasing estradiol concentrations. In 48-hour biofilm tests, elevated protein levels were found for both strains of P. intermedia, and the strains P. nigrescens ATCC 33263 and P. pallens AHN 9283 in the presence of estradiol. The P. intermedia strains also increased the levels of polysaccharide formation in the biofilm. Coaggregation of the P. intermedia group organisms with Fusobacterium nucleatum was enhanced only in P. intermedia AHN 8290. In conclusion, our in vitro experiments indicate that estradiol regulates planktonic growth, coaggregation, polysaccharide production, and biofilm formation characteristics of P. intermedia, P. nigrescens, and P. pallens differently. These results may, at least partly, explain the differences seen in their contribution to the pathogenesis of pregnancy-related gingivitis.


      PubDate: 2014-03-05T00:43:08Z
       
  • An antilisterial bacteriocin BacFL31 produced by Enterococcus faecium FL31
           with a novel structure containing hydroxyproline residues
    • Abstract: Publication date: Available online 25 February 2014
      Source:Anaerobe
      Author(s): Ahlem Chakchouk-Mtibaa , Lobna Elleuch , Slim Smaoui , Soumaya Najah , Imen Sellem , Slim Abdelkafi , Lotfi Mellouli
      A new bacterium called FL31, which was selected for its antimicrobial activity against the pathogenic bacterium Listeria monocytogenes, was identified as Enterococcus faecium and noted to produce an antibacterial proteinaceous substance (BacFL31). The active peptide from the cell-free supernatant of Enterococcus faecium FL31 was purified in four steps and the results revealed a single band with an estimated molecular mass of approximately 3.5 kDa. The N-terminal amino acid sequence of the purified BacFL31 “GLEESXGHXGQXGPXGPXGAXGP” (X = hydroxyproline) showed the presence of six hydorxyproline residues. It displayed a bactericidal mode of action against L. Monocytogenes. Its application at 400 AU/g was also noted to constitute an effective approach for preventing the contamination and growth of the pathogenic bacterium Listeria monocytogenes during the storage of minced beef meat at 4 °C.


      PubDate: 2014-02-28T00:06:40Z
       
  • Effects of single- and multi-strain probiotics on biofilm formation and in
           vitro adhesion to bladder cells by urinary tract pathogens
    • Abstract: Publication date: Available online 25 February 2014
      Source:Anaerobe
      Author(s): C.M.C. Chapman , G.R. Gibson , I. Rowland
      Purpose There is increasing evidence that probiotic bacteria can inhibit and/or prevent urinary tract infections. Possible mechanisms include prevention of adhesion of pathogens to the bladder epithelium and inhibition of biofilm formation. Currently there is interest in the comparative efficacy of single probiotics vs. strain mixtures. We have therefore tested the inhibitory activity of four single probiotics and four probiotic mixtures towards the urinary tract pathogens Escherichia coli NCTC 9001 and Enterococcus faecalis NCTC 00775 Methods Inhibition of biofilm formation by cell-free supernatants was tested using the Crystal Violet assay, while prevention of pathogen adhesion to host cells was tested by using bladder cancer cells as a model for the human urinary tract. Results Under pH-controlled conditions, there was no significant inhibition of biofilm formation by any treatment. Without pH control, 5/8 treatments significantly inhibited biofilm production by E. coli, while 5/8 treatments inhibited production by Ent. faecalis. Using data from all crystal violet assays, there was no significant difference in the ability of single- and multi-strain probiotics to inhibit biofilm formation. In the cell culture assays, all treatments were able to significantly reduce numbers of pathogenic cells adhering to host cells by 2.5.-3.5 logs. No significant difference was observed between the displacement caused by single strains and mixtures for either pathogen. Conclusions Inhibition of biofilm seems to be a major mechanism of urinary tract pathogen exclusion, related to, and possibly dependent upon, the probiotic ability to reduce environmental pH. Exclusion via competition of binding sites is a possible in vivo mechanism for these probiotics. If an additive or synergistic effect exists between strains within a mixture, it does not manifest itself in a greater effect through these two inhibitory mechanisms.


      PubDate: 2014-02-28T00:06:40Z
       
  • Methanogenic archaea diversity in Hanwoo (Bos taurus coreanae) rumen
           fluid, rectal dung, and barn floor manure using a culture-independent
           method based on mcrA gene sequences
    • Abstract: Publication date: Available online 7 February 2014
      Source:Anaerobe
      Author(s): Aileen Rose P. Daquiado , Kye Man Cho , Tae Young Kim , Sam Churl Kim , Hong-Hee Chang , Yong Bok Lee
      The diversity of methanogenic archaea associated with Korean Hanwoo cattle was analyzed using mcrA gene sequences from samples of rumen fluid (RF), rectal dung (RD), and barn floor manure (BFM). The predominant species were Methanobrevibacter ruminantium in RF and BFM(63.6% and 62.4%, respectively) and Methanocorpusculum labreanum in RD (53.2%).


      PubDate: 2014-02-09T03:55:44Z
       
  • Detection of carbapenemase activities of Bacteroides fragilis strains with
           matrix-assisted laser desorption ionization – Time of flight mass
           spectrometry (MALDI-TOF MS)
    • Abstract: Publication date: Available online 27 January 2014
      Source:Anaerobe
      Author(s): Åsa Johansson , Elisabeth Nagy , József Sóki
      Today resistance against carbapenems is considered an emerging problem in Bacteroides fragilis. Carbapenemase activities produced by aerobic bacteria have been detected by looking at hydrolysis of carbapenems with MALDI-TOF MS, but this technique was never used for anaerobic bacteria. We have developed a protocol for detection and verification of carbapenemase production in B. fragilis within 2.5 h. Twenty-eight strains of B. fragilis were tested. Of the sixteen cfiA-positive strains all showed hydrolysis of ertapenem, whereas the twelve cfiA-negative strains showed no hydrolysis. Ertapenem hydrolysis could be inhibited with 2,6-Pyridinecarboxylic acid (DPA) in all cfiA-positive strains, verifying the presence of the metallo-beta-lactamase. Here we show a rapid way to detect carbapenemase activities of B. fragilis strains.


      PubDate: 2014-01-31T17:06:03Z
       
  • A rare case of histopathological bladder necrosis associated with
           Actinobaculum schaalii: the incremental value of an accurate
           microbiological diagnosis using 16S rDNA sequencing
    • Abstract: Publication date: Available online 29 January 2014
      Source:Anaerobe
      Author(s): Romain Lotte , Matthieu Durand , Aurélie Mbeutcha , Damien Ambrosetti , Céline Pulcini , Nicolas Degand , Joyce Loeffler , Raymond Ruimy , Jean Amiel
      We describe here a rare case of bladder wall necrosis associated with Actinobaculum schaalii in a 72-year-old patient with non-muscle-invasive bladder cancer (NMIBC). A. schaalii microbiological diagnosis requires high index of suspicion and accurate identification methods such as 16S rDNA sequencing or MALDI-TOF Mass spectrometry.


      PubDate: 2014-01-31T17:06:03Z
       
  • In vitro growth characteristics and volatile sulfur compound production of
           Solobacterium moorei
    • Abstract: Publication date: Available online 31 January 2014
      Source:Anaerobe
      Author(s): Abish S. Stephen , Declan P. Naughton , Robert L. Pizzey , David J. Bradshaw , Gary R. Burnett
      Solobacterium moorei has recently been implicated as a causative agent of halitosis. In vitro experiments to evaluate the role of S. moorei in halitosis have, however, been complicated by a paucity of information on the ideal conditions for culturing this organism. This work aimed to optimize a liquid culture medium for S. moorei, and to determine the growth-curve of the organism. Further, the ability of S. moorei to generate volatile sulfur compounds was investigated and compared quantitatively to other oral anaerobes by an optimized head-space gas chromatography method. Serum-supplementation of standard liquid growth media gave greater growth of S. moorei than non-supplemented broths, with the best medium found to be serum-supplemented tryptone soya broth. S. moorei was able to metabolize cysteine directly to hydrogen sulfide, but was unable to produce methanethiol from methionine. S. moorei produced 2-3 times more hydrogen sulfide (normalized for colony forming units) than Porphyromonas gingivalis and Veillonella dispar, but considerably less than Fusobacterium nucleatum. The study has identified reliable growth conditions for culture of S. moorei, which were employed to show that S. moorei has the requisite biochemistry consistent with a potential role in halitosis.


      PubDate: 2014-01-31T17:06:03Z
       
  • Detection and partial characterization of a bacteriocin-like substance
           produced by Lactobacillus fermentum CS57 isolated from human vaginal
           secretions
    • Abstract: Publication date: Available online 21 January 2014
      Source:Anaerobe
      Author(s): Carla Sabia , Immacolata Anacarso , Alberto Bergonzini , Raffaele Gargiulo , Mario Sarti , Carla Condò , Patrizia Messi , Simona de Niederhausern , Ramona Iseppi , Moreno Bondi
      Lactobacilli (150) from human vaginal secretions were tested for the production of antimicrobial substances which can provide a physiological defense against the pathogenic microorganisms in the vaginal area. Sixteen of the isolates (10.6%) showed antibacterial activity against one or several closely related microorganisms used as indicators. Lactobacillus fermentum CS57 was the best producer and secretes a bacteriocin-like substance (BLS) with antagonistic activity against Streptococcus agalactiae and Candida albicans. The compound was susceptible to the proteolytic enzymes and was heat labile. The mode of action was identified as bactericidal. The crude activity of the L. fermentum CS57 BLS was linked to a substance with a molecular weight larger than 30 kDa. Plasmid analysis of L. fermentum CS57 revealed the presence of a plasmid band with molecular weight of 54.7 kb. All L. fermentum CS57 non-producer variants (BLS-), obtained by curing experiments, showed loss of plasmid band and were susceptible to the BLS of the original strain. Therefore antimicrobial activity and immunity production seem to be linked to genes located on that same plasmid. Taking into account our results, L. fermentum CS57 could be considered a candidate for potential use as probiotic for the prophylaxis of vaginal human infections.


      PubDate: 2014-01-23T02:41:36Z
       
  • Profile of anaerobic bacteriology of middle ear aspirates in a developing
           country: Does immunocompromise play a role?
    • Abstract: Publication date: Available online 17 January 2014
      Source:Anaerobe
      Author(s): Adebola Stephen Oluwatosin , Ologe Foluwasayo Emmanuel , Alabi Biodun Sulyman , Nwabuisi Charles , Fowotade Adeola
      Objectives The study intends to report the profiles of anaerobic bacteria isolated and attempts to evaluate the impact of immunocompromised status of patients on the disease. Study Design A cross-sectional prospective study Setting ENT clinic, University of Ilorin Teaching Hospital, Nigeria; a 450-bed tertiary health facility Subjects 104 consecutive consenting participants with clinical evidence of CSOM ≥ 12 weeks Methods A hospital-based study conducted over a seven (7) month period. The middle ear aspirate was obtained with the aid of a micropipette and sent immediately for Microscopy, Culture and Sensitivity of both anaerobic and aerobic bacterial isolates. Results A total of 11 patients with chronically discharging ears, of the 104 studied had anaerobic bacteria cultured from their middle ear aspirates. Age ranged from 4 to 50 years with a Male: Female ratio of 1:1.8. A total of 32 isolates (11 anaerobic and 21 aerobic) were recovered. All anaerobic organisms were mixed and included both Peptostreptococcus and Bacteroides. Metronidazole had 100% sensitivity to gram negative and 62.5% to gram positive anaerobic organisms tested. Five (5) patients had immunocompromised states of 11 patients with anaerobic bacteria isolated in middle ear aspirates (group I), while 13 immunocompromised patients of the remaining 93 patients with no anaerobic bacteria isolated (group II). The proportion of anaerobic isolates in group I is higher (p<0.05) than in group II. Conclusion Immunocompromised state and age appear to play key role in presence of the anaerobic organisms recovered from the middle ear of the patients studied.


      PubDate: 2014-01-19T03:09:24Z
       
  • Exopolysaccharide-producing Bifidobacterium animalis subsp. lactis strains
           and their polymers elicit different responses on immune cells from blood
           and gut associated lymphoid tissue
    • Abstract: Publication date: Available online 18 January 2014
      Source:Anaerobe
      Author(s): Claudio Hidalgo-Cantabrana , Milica Nikolic , Patricia López , Ana Suárez , MarijaMiljkovic , Milan Kojic , Abelardo Margolles , Natasa Golic , Patricia Ruas-Madiedo
      The effect of exopolysaccharide (EPS) producing bifidobacteria, and the EPS derived thereof, on the modulation of immune response was evaluated. Cells isolated from gut associated lymphoid tissue (GALT) and from peripheral blood mononuclear cells (PBMC) of naïve rats were used. The proliferation and cytokine production of these immune cells in the presence of the three isogenic Bifidobacterium animalis subsp. lactis strains (A1, A1dOx and A1dOxR), as well as their purified polymers, were in vitro analysed. The cytokine pattern produced by immune cells isolated from GALT showed that most levels remained stable in the presence of the three strains or their corresponding polymers. However, in PBMC the UV-inactivated bacteria induced higher levels of the ratios IFNγ/IL-17, TNFα/IL-10 and TNFα/TGFβ, and no variation in the ratio IFNγ/IL-4. Thus, B. animalis subsp. lactis strains were able to activate blood monocytes as well as T lymphocytes towards a mild inflammatory Th1 response. Furthermore, only the EPS-A1dOxR was able to stimulate a response in a similar way than its EPS-producing bacterium. Our work supports the notion that some bifidobacterial EPS could play a role in mediating the dialog of these microorganisms with the immune system. In addition, this study emphasizes the effect that the origin of the immune cells has in results obtained; this could explain the great amount of contradiction found in literature about the immunomodulation capability of EPS from probiotic bacteria.
      Graphical abstract image

      PubDate: 2014-01-19T03:09:24Z
       
  • The same clade of Clostridium botulinum strains is causing avian botulism
           in southern and northern Europe
    • Abstract: Publication date: Available online 11 January 2014
      Source:Anaerobe
      Author(s): Ibone Anza , Hanna Skarin , Dolors Vidal , Anna Lindberg , Viveca Båverud , Rafael Mateo
      Avian botulism is a paralytic disease caused by Clostridium botulinum-produced botulinum neurotoxins (BoNTs), most commonly of type C/D. It is a serious disease of waterbirds and poultry flocks in many countries in Europe. The objective of this study was to compare the genetic relatedness of avian C. botulinum strains isolated in Spain with strains isolated in Sweden using pulsed-field gel electrophoresis (PFGE). Fifteen strains were isolated from Spanish waterbirds using an immunomagnetic separation technique. Isolates were characterized by PCR, and all were identified as the genospecies Clostridium novyi sensu lato and eight harbored the gene coding for the BoNT type C/D. PFGE analysis of the strains revealed four highly similar pulsotypes, out of which two contained strains from both countries. It also showed that outbreaks in wild and domestic birds can be caused by the same strains. These results support a clonal spreading of the mosaic C. botulinum type C/D through Europe and give relevant information for future epidemiological studies.


      PubDate: 2014-01-15T04:08:11Z
       
  • Identification of Bifidobacterium spp. using hsp60 PCR-RFLP analysis: An
           update
    • Abstract: Publication date: Available online 4 January 2014
      Source:Anaerobe
      Author(s): Verena Stenico , Samanta Michelini , Monica Modesto , Loredana Baffoni , Paola Mattarelli , Bruno Biavati
      A PCR-RFLP technique has been applied on 13 species of Bifidobacterium in order to update a previous study carried out by Baffoni et al.[1]. This method is based on the restriction endonuclease activity of HaeIII on the PCR-amplified hsp60 partial gene sequence, and allow a rapid and efficient identification of Bifidobacterium spp. strains at species and subspecies level.


      PubDate: 2014-01-07T04:35:57Z
       
  • Finding a robust strain for biomethanation: anaerobic fungi
           (Neocallimastigomycota) from the Alpine ibex (Capra ibex) and their
           associated methanogens
    • Abstract: Publication date: Available online 30 December 2013
      Source:Anaerobe
      Author(s): Stefanie Leis , Philipp Dresch , Ursula Peintner , Katerina Fliegerová , Adolf Michael Sandbichler , Heribert Insam , Sabine Marie Podmirseg
      Anaerobic fungi occupy the rumen and digestive tract of herbivores, where they play an important role in enzymatic digestion of lignocellulosic and cellulosic substrates, i.e. organic material that their hosts are unable to decompose on their own. In this study we isolated anaerobic fungi from a typical alpine herbivore, the Alpine ibex (Capra ibex). Three fungal strains, either as pure culture (ST2) or syntrophic co-culture with methanogens (ST3, ST4) were successfully obtained and morphologically characterised by different microscopy- and staining-techniques and by rDNA ITS gene sequencing. The isolated fungi were identified as Neocallimastix frontalis (ST2) and Caecomyces communis (ST3 and ST4). We introduce a novel field of application for lactofuchsin-staining, combined with confocal laser scanning microscopy. This approach proved as an effective method to visualize fungal structures, especially in the presence of plant biomass, generally exhibiting high autofluorescence. Moreover, we could demonstrate that fungal morphology is subject to changes depending on the carbon source used for cultivation. Oxygen tolerance was confirmed for both, C. communis-cultures for up to three, and for the N. frontalis-isolate for up to twelve hours, respectively. With PCR, FISH and an oligonucleotide microarray we found associated methanogens (mainly Methanobacteriales) for Caecomyces communis, but not for Neocallimastix frontalis.


      PubDate: 2014-01-03T19:36:22Z
       
  • Editorial board
    • Abstract: Publication date: February 2014
      Source:Anaerobe, Volume 25




      PubDate: 2014-01-03T19:36:22Z
       
  • Evaluation of normalization reference genes for RT-qPCR analysis of spo0A
           and four sporulation sigma factor genes in Clostridium botulinum Group I
           strain ATCC 3502
    • Abstract: Publication date: Available online 2 January 2014
      Source:Anaerobe
      Author(s): David G. Kirk , Eveliina Palonen , Hannu Korkeala , Miia Lindström
      Heat-resistant spores of Clostridium botulinum can withstand the pasteurization processes in modern food processing. This poses a risk to food safety as spores may germinate into botulinum neurotoxin-producing vegetative cells. Sporulation in Bacillus subtilis, the model organism for sporulation, is regulated by the transcription factor Spo0A and four alternative sigma factors, SigF, SigE, SigG, and SigK. While the corresponding regulators are found in available genomes of C. botulinum, little is known about their expression. To accurately measure the expression of these genes using quantitative reverse-transcriptase PCR (RT-qPCR) during the exponential and stationary growth phases, a suitable normalization reference gene is required. 16S rrn, adK, alaS, era, gluD, gyrA, rpoC, and rpsJ were selected as the candidate reference genes. The most stable candidate reference gene was 16S ribosomal RNA gene (rrn), based on its low coefficient of variation (1.81%) measured during the 18-hour study time. Using 16S rrn as the normalization reference gene, the relative expression levels of spo0A, sigE, sigF, sigG, and sigK were measured over 18 hours. The pattern of expression showed spo0A expression during the logarithmic growth phase, followed by a drop in expression upon entry to the stationary phase. Expression levels of sigF, sigE, and sigG peaked simultaneously at the end of the exponential growth phase. Peak expression of sigK occurred at 18 hours, however low levels of expression were detected during the exponential phase. These findings suggest these sigma factors play a role in C. botulinum sporulation that is similar, but not equal, to their role in the B. subtilis model.


      PubDate: 2014-01-03T19:36:22Z
       
  • Characterization of bovine ruminal and equine cecal microbial populations
           enriched for enhanced nitro-toxin metabolizing activity
    • Abstract: Publication date: Available online 26 December 2013
      Source:Anaerobe
      Author(s): Ying Zhang , Ruijun Long , Christine M. Warzecha , Josie A. Coverdale , Elizabeth A. Latham , Michael E. Hume , Todd R. Callaway , Mathew R. O'Neil , Ross C. Beier , Robin C. Anderson , David J. Nisbet
      The nitrotoxins 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) are produced by a wide variety of leguminous plants, including over 150 different species and varieties of Astragalus potentially grazed by livestock. These toxins are known to be detoxified by at least one ruminal bacterium but detoxification by bacteria from other gut habitats is not known. In the present study, mixed populations of bovine ruminal and equine cecal microbes were enriched for NPA-metabolizing bacteria via consecutive 24–72 h culture in a basal minimal rumen fluid-based medium supplemented with 4.2 mM NPA and H2 as the energy source. Rates of NPA metabolism by the respective populations increased from 58.4 ± 4.8 and 8.6 ± 11.6 nmol NPA/mL per h during initial culture to 88.9 ± 30.6 and 50.2 ± 30.9 nmol NPA/mL per h following enrichment. Results from 3-tube most probable number tests indicated that numbers of NPA-degrading microbes increased 2.1 and 1.8 log10 units during enrichment from numbers measured pre-enrichment (3.9 × 103 and 4.3 × 101 cells/mL for ruminal and equine cecal populations, respectively). Hydrogen, formate, and to a lesser extent, dl-lactic acid, served as electron donors to the enriched populations and CO2 or formate were needed to maintain high rates of NPA-metabolism. The NPA-enriched populations were able to metabolize nitrate which, being a preferred electron acceptor, was antagonistic to NPA metabolism. Supplemental NPA was inhibitory to methanogenesis. Fermentation balance estimates indicated that only 47.6% of carbon available in potential substrates was recovered in headspace CO2, volatile fatty acids or unmetabolized NPA after 72 h incubation of NPA-enriched populations that had metabolized 98% of 8.4 mM added NPA. Overall, these results reveal low level carriage of NPA-metabolizing, CO2 or formate-requiring bacterial populations in the equine cecum yet support the concept that Denitrobacterium detoxificans-like organisms may well be the functional agents of NPA and NPOH detoxification in the populations studied here.


      PubDate: 2013-12-31T06:42:59Z
       
  • Dynamics of biofilm formation during anaerobic digestion of organic waste
    • Abstract: Publication date: Available online 14 December 2013
      Source:Anaerobe
      Author(s): Susanne Langer , Daniel Schropp , Frank R. Bengelsdorf , Maazuza Othman , Marian Kazda
      Biofilm-based reactors are effectively used for wastewater treatment but are not common in biogas production. This study investigated biofilm dynamics on biofilm carriers incubated in batch biogas reactors at high and low organic loading rates for sludge from meat industry dissolved air flotation units. Biofilm formation and dynamics were studied using various microscopic techniques. Resulting micrographs were analysed for total cell numbers, thickness of biofilms, biofilm-covered surface area, and the area covered by extracellular polymeric substances (EPS). Cell numbers within biofilms (1011 cells ml-1) were up to one order of magnitude higher compared to the numbers of cells in the fluid reactor content. Further, biofilm formation and structure mainly correlated with the numbers of microorganisms present in the fluid reactor content and the organic loading. At high organic loading (45 kg VS m-3), the thickness of the continuous biofilm layer ranged from 5 to 160 μm with an average of 51 μm and a median of 26 μm. Conversely, at lower organic loading (15 kg VS m-3), only microcolonies were detectable. Those microcolonies increased in their frequency of occurrence during ongoing fermentation. Independently from the organic loading rate, biofilms were embedded completely in EPS within seven days. The maturation and maintenance of biofilms changed during the batch fermentation due to decreasing substrate availability. Concomitant, detachment of microorganisms within biofilms was observed simultaneously with the decrease of biogas formation. This study demonstrates that biofilms of high cell densities can enhance digestion of organic waste and have positive effects on biogas production.


      PubDate: 2013-12-16T12:11:41Z
       
  • Molecular comparative assessment of the microbial ecosystem in rumen and
           faeces of goats fed alfalfa hay alone or combined with oats
    • Abstract: Publication date: Available online 11 December 2013
      Source:Anaerobe
      Author(s): Hamid Mohammadzadeh , David R. Yáñez-Ruiz , Gonzalo Martínez-Fernandez , Leticia Abecia
      The objective of this work was to compare the biomass and community structure of bacteria, protozoa and archaea communities in samples of rumen and faeces of goats and to what extent the diet (alfalfa hay with or without supplemented oats) offered to them exert an influence. Four cannulated adult goats fistulated in the rumen were used in a cross over design experiment in two experimental periods of 26 days, consisting in 14 days of adaptation, 7 days of sampling rumen contents and 5 days of digestibility measurement. Bacterial, protozoa and archaeal biomass and the communities’ structure was assessed by real time PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE), respectively. The numbers of archaea and bacteria in both rumen and faeces were higher and lower, respectively, in animals fed AH diet (P < 0.005). Contrary, protozoal numbers were not affected by the diet but were lower (P < 0.001) in faeces than in rumen. The analysis of the community structure revealed a consistently different population in structure in rumen and faeces for the three studied microbial groups and that supplementing alfalfa hay with oats led to a decrease in the similarity between sites in the rumen and faeces: similarity indexes for bacteria (57 and 27%), archaea (26 and 9%) and protozoa (62 and 22%) in animals fed AH and AHO diets, respectively.


      PubDate: 2013-12-12T22:26:00Z
       
  • Molecular monitoring of the bacterial community structure in foal feces
           pre- and post-weaning
    • Abstract: Publication date: Available online 4 December 2013
      Source:Anaerobe
      Author(s): Céline Faubladier , Sophie Sadet-Bourgeteau , Christelle Philippeau , Emmanuel Jacotot , Véronique Julliand
      This study assessed the time-scale variability of bacterial community structure in foal feces from birth to 365 days of age using Automated Ribosomal Intergenic Spacer Analysis (ARISA). Fecal samples were collected from five foals two hours after birth (meconium) and in the morning at days 1, 2, 5, 10, 30, 60, 120, 179, 183, 194 and 365. The ARISA profiles were compared using an analysis of similarity (ANOSIM). Although both the age effect and the foal effect were highly significant (P < 0.010), the R-ANOSIM value for the foal effect was very low (R-ANOSIM = 0.089), while that of the age effect was much higher (R-ANOSIM = 0.309). Significant age-related changes were detected between days 0 and 2 (R-ANOSIM = 0.500), days 2 and 10 (R-ANOSIM=0.475) and days 10 and 30 (R-ANOSIM=0.519). No further shifts between consecutive times of sampling were detected in the bacterial community after day 30 and no changes were observed at weaning (day 180). These results show that the establishment of the intestinal bacterial community in foals is a sequential process, which reaches its climax state at around one month of age. Further studies using new generation sequencing based methods could be conducted to identify which bacterial genera are establishing in foals during the first month of life.


      PubDate: 2013-12-05T21:23:58Z
       
  • Editorial board
    • Abstract: Publication date: December 2013
      Source:Anaerobe, Volume 24




      PubDate: 2013-12-05T21:23:58Z
       
  • Toxigenic genes, spoilage potential, and antimicrobial resistance of
           Bacillus cereus group strains from ice cream
    • Abstract: Publication date: Available online 3 December 2013
      Source:Anaerobe
      Author(s): Seza Arslan , Ayla Eyi , Rümeysa Küçüksarı
      Bacillus spp. can be recovered from almost every environment. It is also found readily in foods, where it may cause food spoilage and/or food poisoning due to its toxigenic and pathogenic nature, and extracellular enzymes. In this study, 29 B. cereus group strains from ice cream were examined for the presence of following virulence genes hblC, nheA, cytK and ces genes, and tested for a range of the extracellular enzymes, and antimicrobial susceptibility. The strains were found to produce extracellular enzymes: proteolytic and lipolytic activity, gelatin hydrolysis and lecithinase production (100%), DNase production (93.1%) and amylase activity (93.1%). Of 29 strains examined, 24 (82.8%) showed hemolytic activity on blood agar. Beta-lactamase enzyme was only produced by 20.7% of B. cereus group. Among 29 B. cereus group from ice cream, nheA was the most common virulence gene detected in 44.8% of the strains, followed by hblC gene with 17.2%. Four (13.8%) of the 29 strains were positive for both hblC gene and nheA gene. Contrarily, cytK and cesgenes were not detected in any of the strains. Antimicrobial susceptibility of ice cream isolates was tested to 14 different antimicrobial agents using the disc diffusion method. We detected resistance to penicillin and ampicillin with the same rate of 89.7%. Thirty-one percent of the strains were multiresistant to three or more antibiotics. This study emphasizes that the presence of natural isolates of Bacillus spp. harboring one or more enterotoxin genes, producing extracellular enzymes which may cause spoilage and acquiring antibiotic resistance might hold crucial importance in the food safety and quality.


      PubDate: 2013-12-05T21:23:58Z
       
  • Prebiotic effects of almonds and almond skins on intestinal microbiota in
           healthy adult humans
    • Abstract: Publication date: Available online 3 December 2013
      Source:Anaerobe
      Author(s): Zhibin Liu , Xiuchun Lin , Guangwei Huang , Wen Zhang , Pingfan Rao , Li Ni
      Almonds and almond skins are rich in fiber and other components that have potential prebiotic properties. In this study we investigated the prebiotic effects of almond and almond skin intake in healthy humans. A total of 48 healthy adult volunteers consumed a daily dose of roasted almonds (56 g), almond skins (10 g), or commercial fructooligosaccharides (8 g) (as positive control) for 6 weeks. Fecal samples were collected at defined time points and analyzed for microbiota composition and selected indicators of microbial activity. Different strains of intestinal bacteria had varying degrees of growth sensitivity to almonds or almond skins. Significant increases in the populations of Bifidobacterium spp. and Lactobacillus spp. were observed in fecal samples as a consequence of almond or almond skin supplementation. However, the populations of Escherichia coli did not change significantly, while the growth of the pathogen Clostridum perfringens was significantly repressed. Modification of the intestinal microbiota composition induced changes in bacterial enzyme activities, specifically a significant increase in fecal β-galactosidase activity and decreases in fecal β-glucuronidase, nitroreductase and azoreductase activities. Our observations suggest that almond and almond skin ingestion may lead to an improvement in the intestinal microbiota profile and a modification of the intestinal bacterial activities, which would induce the promotion of health beneficial factors and the inhibition of harmful factors. Thus we believe that almonds and almond skins possess potential prebiotic properties.


      PubDate: 2013-12-05T21:23:58Z
       
  • Sample prefractionation with liquid isoelectric focussing enables in depth
           microbial metaproteome analysis of mesophilic and thermophilic biogas
           plants
    • Abstract: Publication date: Available online 3 December 2013
      Source:Anaerobe
      Author(s): F. Kohrs , R. Heyer , A. Magnussen , D. Benndorf , T. Muth , A. Behne , E. Rapp , R. Kausmann , M. Heiermann , M. Klocke , U. Reichl
      Biogas production from energy crops and biodegradable waste is one of the major sources for renewable energies in Germany. Within a biogas plant (BGP) a complex microbial community converts biomass to biogas. Unfortunately, disturbances of the biogas process occur occasionally and cause economic losses of varying extent. Besides technical failures the microbial community itself is commonly assumed as a reason for process instability. To improve the performance and efficiency of BGP, a deeper knowledge of the composition and the metabolic state of the microbial community is required and biomarkers for monitoring of process deviations or even the prediction of process failures have to be identified. Previous work based on 2D-electrophoresis demonstrated that the analysis of the metaproteome is well suited to provide insights into the apparent metabolism of the microbial communities. Using SDS-PAGE with subsequent mass spectrometry, stable protein patterns were evaluated for a number of anaerobic digesters. Furthermore, it was shown that severe changes in process parameters such as acidification resulted in significant modifications of the metaproteome. Monitoring of changing protein patterns derived from anaerobic digesters, however, is still a challenge due to the high complexity of the metaproteome. In this study, different combinations of separation techniques to reduce the complexity of proteomic BGP samples were compared with respect to the subsequent identification of proteins by tandem mass spectrometry (MS/MS): (i) 1D: proteins were tryptically digested and the resulting peptides were separated by reversed phase chromatography prior to MS/MS. (ii) 2D: proteins were separated by GeLC-MS/MS according to proteins molecular weights before tryptic digestion (iii) 3D: proteins were separated by gel-free fractionation using isoelectric focusing (IEF) conducted before GeLC-MS/MS. For this study, a comparison of two anaerobic digesters operated at mesophilic and at thermophilic conditions was conducted. The addition of further separation dimensions before protein identification increased the number of identified proteins. On the other hand additional fractionation steps increased the experimental work load and the time required for LC-MS/MS measurement. The high resolution of the 3D-approach enabled the detection of approximately 750 to 1,650 proteins covering the main pathways of hydrolysis, acidogenesis, acetogenesis and methanogenesis. Methanosarcinales dominated in the mesophilic BGP, whereas Methanomicrobiales were highly abundant in the thermophilic BGP. Pathway analysis confirmed the taxonomic results and revealed that the acetoclastic methanogenesis occurred preferentially at mesophilic conditions, whereas exclusively hydrogenotrophic methanogenesis was detected in thermophilic BGP. However, for the identification of process biomarkers by comprehensive screening of BGP it will be indispensable to find a balance between the experimental efforts and analytical resolution.


      PubDate: 2013-12-05T21:23:58Z
       
  • Bacterial Diversity Associated with Feeding Dry Forage at Different
           Dietary Concentrations in the Rumen Contents of Mehshana Buffalo (Bubalus
           bubalis) using 16S Pyrotags
    • Abstract: Publication date: Available online 3 December 2013
      Source:Anaerobe
      Author(s): D.W. Pitta , S. Kumar , B. Veiccharelli , N. Parmar , B. Reddy , C.G. Joshi
      Pyrosequencing of 16S rRNA gene targeting bacteria was applied to identify diet-induced shifts in the microbiome of both solid and liquid ruminal fractions retrieved from water buffalo fed different diets. The depth of coverage of metabolically active bacteriain a community using different primer pairs was also investigated. To assess reproducibility, animal to animal variation was considered in all phylogenetic and community comparisons. The experiment included four non-lactating water buffaloes fed three different diets for six weeks each; diets were M1 (50% concentrate: 50% dry roughage), M2 (25% concentrate: 75% dry roughage) and M3 (100% dry roughage). A total of 333, 851 pyrotags were analysed in this study. Phylogenetic analysis revealed significant differences in the rumen microbiome mediated by primer and diet (P<0.05). Differences in community composition due to primer, diet, fraction and animal were compared using unweighted and weighted UniFrac analysis. Clustering of communities was largely explained by primer differences in both weighted and unweighted UniFrac analyses (P<0.001). In the weighted analysis, communities clustered by diets (P<0.05) and fractions (P<0.08) while no inter-animal variation was observed. The identified repertoire of bacterial populations was dependent on the primer pair, as targeting the V4-V5 region resulted in greater diversity profiles of the microbiome. Within each primer pair, dietary changes altered the community composition with noticeable shifts at genus level. Genera such as Ruminococcus and Fibrobacter (P<0.05) were higher in abundance on M3 diet while Prevotella dominated (P<0.05) on M1 diet.


      PubDate: 2013-12-05T21:23:58Z
       
  • Lactulose promotes equol production and changes the microbial community
           during in vitro fermentation of daidzein by fecal inocula of sows
    • Abstract: Publication date: Available online 4 December 2013
      Source:Anaerobe
      Author(s): Wei-jiang Zheng , Yan-Jun Hou , Yong Su , Wen Yao
      Equol has higher biological effects than other isoflavones. However, only about 30-50% of humans possess a microbiota capable of producing equol from dietary daidzein. In recent years, interest has grown in dietary applications to improve equol production in human and other animals. In this study, lactulose was used as a potential equol-promoting prebiotic in vitro. The effect of lactulose on transformation of daidzein into equol by sows’ fecal microbiota was investigated. Results showed that lactulose treatment improved bacteria growth parameters, changing the kinetics of fermentation in vitro. Lactulose significantly increased total gas production, T1/2, Tmax, and Rmax. Furthermore, lactulose altered the microflora composition, increased equol production associated with a reduction in the population of methanogen and increased the sulfate-reducing bacteria population during 24 hours of incubation. Here, we report for the first time that in a certain condition (sealing or high pressure), via a dihydrodaidzein (DHD) pathway equol might be able to reform to daidzein by further metabolism using lactulose as a substrate. This study proposes that “hydrogen-producing prebiotic” might be a novel way to promote equol production in vivo or in vitro.


      PubDate: 2013-12-05T21:23:58Z
       
  • Characterization of the collagen-like exosporium protein, BclA1, of
           Clostridium difficile Spores
    • Abstract: Publication date: Available online 21 November 2013
      Source:Anaerobe
      Author(s): Marjorie Pizarro-Guajardo , Valeria Olguín-Araneda , Jonathan Barra-Carrasco , Christian Brito-Silva , Mahfuzur R. Sarker , Daniel Paredes-Sabja
      Spores of Clostridium difficile are essential for infection, persistence and transmission of C. difficile infections (CDI). Proteins of the surface of C. difficile spores are thought to be essential for initiation and persistence of CDI. In this work, we demonstrate that three Clostridium difficile collagen-like exosporium proteins (BclA) encoded in the C. difficile 630 genome are expressed during sporulation and localize to the spore via their N-terminal domains. Using polyclonal antibodies against the N- and C-terminal domains and full length BclA1 we demonstrate that BclA1 is likely to be localized to the exosporium layer, presumably undergoes post-translational cleavages and might be cross-linked with other exosporium proteins. The collagen-like region of recombinant BclA1 and BclA2 was susceptible to collagenase degradation. Collagenase digestion assay of C. difficile spores suggests that, similarly as in B. anthracis BclA, the N-terminal domain and the C-terminal domain of BclA1 might be buried in the basal layer and oriented to the exosporium surface, respectively. We also demonstrate that the collagen-like BclAs proteins do not contribute to the spore hydrophobicity and its absence slightly increased the adherence of spores to Caco-2 cells. BclA1 was also shown to have poor immunogenic properties. These results provide the first study on the BclA1 collagen-like proteins of C. difficile spores.


      PubDate: 2013-11-23T11:41:27Z
       
  • Variability of S-layer proteins in Lactobacillus helveticus strains
    • Abstract: Publication date: Available online 21 November 2013
      Source:Anaerobe
      Author(s): Adam Waśko , Magdalena Polak-Berecka , Adam Kuzdraliński , Tomasz Skrzypek
      The presence of S-layer proteins in the cell envelope of Lactobacillus helveticus may be technologically important. S-layer proteins are the adhesion site for cell envelope proteinase, which forms the proteolytic pathway in bacteria. Eleven strains of L. helveticus were examined for the presence of S-layer proteins and slpH genes. S-layer proteins from six strains were identified and sequenced. Multiple alignments of the deduced amino acid sequences demonstrated a strong sequence conservation of all Slp studied. Transmission Electron Microscopy analysis of the cells revealed the typical cell wall architecture of the S-layer. This is the first report on characterisation of glycosylated S-layer proteins from different strains of L. helveticus. The amino acid composition, the secondary structure, and the physical properties of these proteins were found to be quite similar to those of S-layer proteins from other lactobacilli. However, PCR analysis revealed that five of the examined strains of L. helveticus did not have slpH genes. This finding suggests that S-layer protein genes cannot be considered as housekeeping genes and cannot be used as molecular markers for L. helveticus.


      PubDate: 2013-11-23T11:41:27Z
       
  • In vitro fermentation of prebiotic oligosaccharides by Bifidobacterium
           lactis HN019 and Lactobacillus spp.
    • Abstract: Publication date: Available online 14 November 2013
      Source:Anaerobe
      Author(s): Ian M. Sims , Jason L.J. Ryan , Sang H. Kim
      The utilisation of various prebiotic oligosaccharides by probiotic strains of Bifidobacterium lactis, Lactobacillus rhamnosus and L. acidophilus was investigated in order to determine the synbiotic potential of various prebiotic/probiotic combinations. Analysis by HPLC and high-performance anion-exchange chromatography of the cell-free medium taken during growth of the three probiotic bacteria showed differences in the consumption of the various oligosaccharides. Analysis of galactooligosaccharides showed that both L. rhamnosus and B. lactis consumed mostly mono- and di-saccharide, while L. acidophilus consumed oligosaccharides up to trisaccharide. Both B. lactis and L. acidophilus utilised fructooligosaccharides and inulin, but showed different patterns of oligosaccharide consumption. Only L. rhamnosus grew on β-glucan oligosaccharides and preferentially consumed the trisaccharide. The results indicate the synbiotic potential of the various probiotic/prebiotic combinations, particularly L. acidophilus/galactooligosaccharides, L. acidophilus/fructooligosaccharides or inulin and L. rhamnosus/β-glucan oligosaccharides.


      PubDate: 2013-11-16T01:33:46Z
       
  • Adhesive properties of Clostridium perfringens to extracellular matrix
           proteins collagens and fibronectin
    • Abstract: Publication date: Available online 15 November 2013
      Source:Anaerobe
      Author(s): Yasuo Hitsumoto , Naomi Morita , Ryosuke Yamazoe , Mika Tagomori , Tsutomu Yamasaki , Seiichi Katayama
      The adhesive properties of Clostridium perfringens to collagens, gelatin, fibronectin (Fn), Fn-prebound collagens, and Fn-prebound gelatin were investigated. C. perfringens could bind to Fn-prebound collagen type II, type III, and gelatin, but not to gelatin or collagens except for collagen type I directly. Recombinant Fn-binding proteins of C. perfringens, rFbpA and rFbpB, were used to examine Fn-mediated bacterial adherence to collagen type I. In the presence of rFbps, C. perfringens adherence to Fn-prebound collagen type I was inhibited in a dose-dependent manner. Fn was not released from the coated collagen type I by the presence of rFbps, and rFbps did not bind to collagen type I. Thus, the inhibition of C. perfringens binding to Fn-prebound collagen type I by rFbps could not be explained by the removal of Fn from collagen or by the competitive binding of rFbps to collagen. Instead, both rFbps were found to bind to C. perfringens. These results suggest the possibility that rFbps may bind to the putative Fn receptor expressed on C. perfringens and competitively inhibit Fn binding to C. perfringens.


      PubDate: 2013-11-16T01:33:46Z
       
  • Incidence and Mortality Associated with Clostridium difficile Infection at
           a Japanese Tertiary Care Center
    • Abstract: Publication date: Available online 1 November 2013
      Source:Anaerobe
      Author(s): Hitoshi Honda , Akinori Yamazaki , Yumiko Sato , Erik R. Dubberke
      Background Although increases in Clostridium difficile infection (CDI) incidence and severity have been observed in numerous countries, the incidence of CDI in Japan remains unclear. The goal of this study was to determine the incidence and outcomes of CDI at a Japanese tertiary care center. Materials and Methods Retrospective cohort study in patients with CDI was conducted at a 550-bed, tertiary care, academic center in Sapporo, Japan from September 2010 through August 2012. CDI cases diagnosed by enzyme immunoassays were categorized per internationally recognized surveillance definitions. Data on demographic characteristics, medication exposures, CDI presentation, and CDI treatment were collected on all CDI cases. Factors associated with 30-day all-cause mortality after the completion of CDI treatment were also investigated. Results There were 32,296 admissions and 350,074 patient-days from 22,863 patients during the study period; 126 patients were diagnosed with CDI. The median age of CDI case patients was 78 years. Healthcare facility-onset (HO) CDI accounted for 86.5% of CDI cases, with a HO-CDI incidence of 3.11 cases per 10,000 patient-days. Three patients underwent surgery for CDI (2.4%) and 19 patients (15%) died within a 30 days of completing CDI treatment. Factors independently associated with mortality were diabetes mellitus and shock at time of CDI diagnosis. Conclusions The CDI incidence was lower than that typically reported from North American hospitals, but the proportion of patients requiring surgical therapy and dying within 30 days of CDI in non-outbreak settings was higher. More study is needed to determine why CDI incidence is low relative to CDI-associated outcomes in Japan.


      PubDate: 2013-11-04T03:00:36Z
       
  • Bacterial counts from five over-the-counter probiotics: are you getting
           what you paid for?
    • Abstract: Publication date: Available online 1 November 2013
      Source:Anaerobe
      Author(s): Ellie J.C. Goldstein , Diane M. Citron , Marina C. Claros , Kerin L. Tyrrell
      There is concern that the bacterial colony counts present at the time of manufacture and listed on the probiotic package may not be reflective of the numbers viable colonies at the time of purchase and patient consumption thereby diminishing efficacy. We performed a colony count study of three separate samples of five different probiotics purchased from three different stores: Bifidobacterium infantis (Align®); Lactobacillus acidophilus CL1285® and L. casei LBC80R® (Bio-K+®); L. rhamnosus GG (Culturelle®); Saccharomyces boulardii (Florastor®) and “L. acidophilus” and “L. helveticus” (Lactinex®). Approximately 1 gram of powder of each (Lactinex® tablets were crushed before testing) was reconstituted in sterile distilled water, serial 10-fold dilutions were prepared and plated in duplicate onto blood agar plates, with incubation for 48 hours in an anaerobic chamber (except the Saccharomyces which was incubated aerobically) after which colony counts were performed. The Florastor® packaging did not state an expected concentration and was found to have 9.2 x 109–1.3 x 1010 CFU/g. Lactinex®, Align®, Bio-K+®, and Culturelle® had viable colony counts that were similar to those stated on the package.


      PubDate: 2013-11-04T03:00:36Z
       
  • Effect of dietary protein supply originating from soybean meal or casein
           on the intestinal microbiota of piglets
    • Abstract: Publication date: Available online 29 October 2013
      Source:Anaerobe
      Author(s): Vanessa T.S. Rist , Eva Weiss , Nadja Sauer , Rainer Mosenthin , Meike Eklund
      Dietary composition is a major factor influencing the intestinal microbial ecosystem of pigs. To alleviate weaning-associated disorders, variations in dietary protein supply may beneficially affect microbial composition in the gastrointestinal tract of piglets. A total of 48 piglets, fitted with simple ileal T-cannulas, was used to examine the effect of protein supply of either highly digestible casein or less digestible, fiber-rich soybean meal (SBM) on the composition of the intestinal microbiota. Gene copies of 7 bacteria groups were determined by real-time PCR in ileal digesta and feces. Ileal counts of total eubacteria, the Bacteroides group, Enterobacteriaceae and Clostridium Cluster XIVa were higher (P < 0.001) in the casein-based diets. Fecal counts of all analyzed bacterial groups were higher for the SBM-based diets (P < 0.001), except for Enterobacteriaceae (P < 0.05) which were higher in the casein-based diets. Ileal counts of lactobacilli linearly increased as the crude protein level was increased up to 335 g/kg (P < 0.01). The Bacteroides-Prevotella-Porphyromonas group linearly decreased in ileal samples (P < 0.01) and increased in fecal samples (P < 0.05) as the crude protein level in the SBM-based diet was increased. Both, protein level and protein source may affect intestinal microbial balance. Higher dietary protein levels in combination with diets low in fiber contents eventually stimulate proliferation of protein fermenting bacteria in piglet’s large intestine, which may result in intestinal disturbances.


      PubDate: 2013-10-31T02:14:14Z
       
  • The impact of cefepime as first line therapy for neutropenic fever on
           Clostridium difficile rates among hematology and oncology patients
    • Abstract: Publication date: Available online 15 October 2013
      Source:Anaerobe
      Author(s): Eavan G. Muldoon , Lauren Epstein , Tanya Logvinenko , Susan Murray , Shira I. Doron , David R. Snydman
      After changing empiric treatment of febrile neutropenia from meropenem to cefepime, the effect on Clostridium difficile infection (CDI) was investigated. The change was assessed using an autoregressive model. A significant increase in CDI rates occurred following the introduction of cefepime. There may be an association between increased cefepime usage and CDI.


      PubDate: 2013-10-19T05:41:15Z
       
  • Starch structure modulates metabolic activity and gut microbiota profile
    • Abstract: Publication date: Available online 7 October 2013
      Source:Anaerobe
      Author(s): Zhongkai Zhou , Yan Zhang , Paiyun Zheng , Xiaoshan Chen , Yan Yang
      Normal maize starch and high amylose maize starch (HAS) either in native or thermally treated forms were used to investigate the effect of starch structure on the production of metabolites and gut microbiota profile using an anaerobic in vitro system. The changes in starch structure during fermentation were investigated using scanning electron microscopy (SEM), high-performance liquid chromatography (HPLC) and Fourier transform infra-red spectroscopy (FTIR). The native normal starch showed a porous structure during fermentation, indicating it was quickly metabolized by gut bacteria, whereas the HAS showed a smooth structure, suggesting it was utilized gradually. HPLC chromatography showed that amylose fraction with low molecular weight (MW) had a higher resistance to be fermented by gut bacteria than other starch molecular fractions. Thermal treatment enhanced starch fermentation kinetics, especially for amylopectin and high MW amylose fractions. FTIR analysis suggests that the structure of the normal starch, either in native or thermally treated, was less organized compared to HAS, and this structural character led to the normal starch to be utilised more quickly by gut bacteria with a faster increase in the IR ratio 1047/1022cm-1 (P<0.01) during fermentation. The measurement of metabolic activity indicates that the normal starch with a less organized structure was utilised faster and generated more acetate and lactate during fermentation; HAS with a highly organized structure was more likely to produce butyrate, corresponding the significant increase (P<0.001) in the populations of butyrate-producing strains (Faecalibacterium prausnitzii and Eubacterium hallii) in the cultures. This study reveals that fermentation kinetics of starch substrate is one of important characteristics for manipulating gut microbiota fermentation behaviours.


      PubDate: 2013-10-07T21:29:19Z
       
  • The effects of stress hormones on growth of selected periodontitis related
           bacteria
    • Abstract: Publication date: Available online 13 September 2013
      Source:Anaerobe
      Author(s): H.F.R. Jentsch , D. März , Monika Krüger
      The focus of this study was to examine in vitro the effects of stress hormones (catecholamines: epinephrine, norepinephrine, dopamine and hydrocortisone: cortisol) on the growth of four anaerobic species of periodontitis-related bacteria (Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia and Tannerella forsythia) and one facultative anaerobic species (Eikenella corrodens). Bacterial growth was determined by two different methods: fluorescence in situ hybridization (FISH), and the viable count by culture method. To simulate stress, each single strain was grown in a special growth medium with three different concentrations of each hormone, using an anaerobic chamber at 37°C. Growth of F. nucleatum increased in the presence of all stress hormones. Growth of P. gingivalis was not significantly influenced by any hormone. Growth of P. intermedia and E. corrodens was inhibited by almost all stress hormones tested. Both methods of analysis revealed that the highest concentrations of norepinephrine and cortisol increased the growth of T. forsythia. Different hormones have a different effect on the growth of periodontitis-related bacteria in vitro. It appears that bacterial viability is more strongly influenced than is bacterial metabolic activity. The growth of F. nucleatum particularly and partially of T. forsythia is increased by several stress hormones and may have an additional negative impact on periodontal disease.


      PubDate: 2013-09-14T03:31:43Z
       
  • Treatment approaches including fecal microbiota transplantation for
           recurrent Clostridium difficile infection (RCDI) among infectious disease
           physicians
    • Abstract: Publication date: Available online 4 September 2013
      Source:Anaerobe
      Author(s): Johan S. Bakken , Philip M. Polgreen , Susan E. Beekmann , Francis X. Riedo , Judy A. Streit
      Background Clostridium difficile infection (CDI) was the most common nosocomial infection in the U.S. in 2010. Most cases of CDI respond to a standard course of antibiotics, but recurrent C. difficile infections (RCDI) are increasingly common. Given the lack of randomized clinical trials, it is important to understand how infectious disease physicians are managing RCDI to inform future clinical research. Methods An electronic survey was conducted among members of the Emerging Infections Network (EIN) in October 2012. Respondents were asked to answer specific questions about their treatment approaches toward patients with CDI, including fecal microbiota transplantation (FMT). Results The overall response rate was 621/1212 (51%). The vast majority of respondents had cared for small to moderate numbers of patients with CDI over the prior 6 months, and reported recurrence rates were consistent with published data. Preferred treatment regimens for RCDI showed significant variance from recommendations published in national guidelines. Eighty percent (424/527) of the respondents would consider FMT for patients with RCDI, and of 149 who had FMT available at their institution, 107 (72%) had actually treated >1 patient with FMT in the preceding year. However, significant barriers to institutional adoption of FMT remain for many respondents, despite very good success rates with its use. Conclusions Physicians who regularly care for patients with CDI use a variety of treatment approaches for treating severe or recurrent CDI cases. The results of our survey demonstrate that FMT is used by a growing number of infectious disease providers as an effective and safe treatment alternative for patients with multiple recurrences of C. difficile infection.


      PubDate: 2013-09-06T21:22:36Z
       
  • Lactobacillus plantarum TN627 significantly reduces complications of
           alloxan-induced diabetes in rats
    • Abstract: Publication date: Available online 30 August 2013
      Source:Anaerobe
      Author(s): Wacim Bejar , Khaled Hamden , Riadh Ben Salah , Hichem Chouayekh
      This study aimed to assess the potential of the probiotic strain Lactobacillus plantarum TN627 for preventing alloxan-induced diabetes in rats. The oral administration of this probiotic was noted to significantly improve the immunological parameters, protect the pancreatic tissues, and reduce the pancreatic and plasmatic α-amylase activities and level of plasma glucose in the treated as compared to the control group of rats. Furthermore, this probiotic treatment was observed to markedly reduce pancreatic and plasmatic lipase activities and serum triglyceride and LDL-cholesterol rates and to increase the level of HDL-Cholesterol. It also exerted efficient protective effects on the liver and kidney functions evidenced by significant decreases in serum aspartate transaminase, alanine transaminase, lactate dehydrogenase, and gamma-glutamyl transpeptidase activities, as well as creatinine and urea contents. Taken together, the findings indicate that Lactobacillus plantarum TN627 exhibits attractive in vivo antidiabetic effects that may be helpful in preventing diabetic complications in adult rats.


      PubDate: 2013-09-03T06:15:04Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2014