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BIOLOGY (1316 journals)            First | 1 2 3 4 5 6 7 8 | Last

Economics & Human Biology     Hybrid Journal  
Ecoprint : An International Journal of Ecology     Open Access  
Ecoscience     Full-text available via subscription   (Followers: 2)
Educational Technology Research and Development     Partially Free   (Followers: 132)
Egyptian Journal of Biology     Open Access  
Egyptian Journal of Histology     Partially Free   (Followers: 1)
Egyptian Journal of Natural History     Open Access  
EJNMMI Research     Open Access   (Followers: 1)
Electromagnetic Biology and Medicine     Hybrid Journal   (Followers: 1)
eLife     Open Access   (Followers: 14)
el–Hayah     Open Access   (Followers: 1)
Embo Molecular Medicine     Open Access   (Followers: 3)
EMBO reports     Full-text available via subscription   (Followers: 15)
Emotion Review     Hybrid Journal   (Followers: 10)
Endocrine Connections     Open Access   (Followers: 2)
Engineering & Technology     Hybrid Journal   (Followers: 15)
Engineering Economist, The     Hybrid Journal   (Followers: 3)
Engineering in Life Sciences     Hybrid Journal   (Followers: 3)
Engineering Optimization     Hybrid Journal   (Followers: 5)
Ensaios e Ciência: Ciências Biológicas, Agrárias e da Saúde     Open Access  
Environmental Biology of Fishes     Hybrid Journal   (Followers: 3)
Environmental Biosafety Research     Hybrid Journal   (Followers: 1)
Environmental Microbiology     Hybrid Journal   (Followers: 7)
Environmental Science & Technology     Full-text available via subscription   (Followers: 220)
Enzyme and Microbial Technology     Hybrid Journal   (Followers: 6)
Epidemiology & Infection     Hybrid Journal   (Followers: 12)
EPMA Journal     Open Access  
ESHRE Monographs     Hybrid Journal  
Ethiopian Journal of Biological Sciences     Open Access   (Followers: 2)
Ethnobiology and Conservation     Open Access   (Followers: 2)
Ethnobotany Research & Applications : a journal of plants, people and applied research     Open Access   (Followers: 5)
Ethology     Hybrid Journal   (Followers: 2)
Ethology Ecology & Evolution     Hybrid Journal   (Followers: 7)
Eukaryotic Cell     Full-text available via subscription   (Followers: 6)
EuPA Open Proteomics     Open Access   (Followers: 1)
EURASIP Journal on Bioinformatics and Systems Biology     Open Access   (Followers: 6)
European Journal of Cell Biology     Hybrid Journal   (Followers: 3)
European Journal of Neuroscience     Hybrid Journal   (Followers: 22)
European Journal of Phycology     Hybrid Journal   (Followers: 5)
European Journal of Protistology     Hybrid Journal   (Followers: 2)
European Journal of Soil Biology     Hybrid Journal   (Followers: 1)
European Online Journal of Natural and Social Sciences     Open Access   (Followers: 11)
European Scientific Journal     Open Access   (Followers: 2)
Evidência - Ciência e Biotecnologia - Interdisciplinar     Open Access  
EvoDevo     Open Access   (Followers: 1)
Evolução e Conservação da Biodiversidade     Open Access  
Evolution     Partially Free   (Followers: 50)
Evolution and Human Behavior     Hybrid Journal   (Followers: 8)
Evolutionary Applications     Open Access   (Followers: 2)
Evolutionary Bioinformatics     Open Access   (Followers: 14)
Evolutionary Biology     Hybrid Journal   (Followers: 15)
Evolutionary Computation     Hybrid Journal   (Followers: 9)
Experimental & Molecular Medicine     Open Access   (Followers: 2)
Experimental and Applied Acarology     Hybrid Journal   (Followers: 1)
Experimental Cell Research     Hybrid Journal   (Followers: 3)
Expert Opinion on Biological Therapy     Hybrid Journal   (Followers: 10)
Expert Opinion on Environmental Biology     Partially Free  
Expert Review of Proteomics     Full-text available via subscription   (Followers: 2)
Extreme Life, Biospeology & Astrobiology - International Journal of the Bioflux Society     Full-text available via subscription   (Followers: 2)
Extremophiles     Hybrid Journal  
F1000Research     Open Access   (Followers: 3)
Familial Cancer     Hybrid Journal   (Followers: 1)
Fatigue & Fracture of Engineering Materials and Structures     Hybrid Journal   (Followers: 12)
Fauna Norvegica     Open Access  
Febs Journal     Hybrid Journal   (Followers: 8)
Feddes Repertorium     Hybrid Journal  
Fems Yeast Research     Hybrid Journal   (Followers: 10)
Field Mycology     Full-text available via subscription   (Followers: 1)
Fish & Shellfish Immunology     Hybrid Journal   (Followers: 6)
Fitoterapia     Hybrid Journal   (Followers: 4)
Fly     Full-text available via subscription  
Folia Biologica     Full-text available via subscription  
Folia Biologica et Oecologica     Open Access   (Followers: 1)
Folia Histochemica et Cytobiologica     Open Access  
Folia Malacologica     Open Access  
Folia Microbiologica     Hybrid Journal   (Followers: 1)
Folia Primatologica     Full-text available via subscription   (Followers: 1)
Food and Bioproducts Processing     Hybrid Journal   (Followers: 1)
Forest Pathology     Hybrid Journal   (Followers: 1)
Forschung     Hybrid Journal  
Foundations of Physics     Hybrid Journal   (Followers: 1)
Free Radical Biology and Medicine     Hybrid Journal   (Followers: 5)
Free Radical Research     Hybrid Journal   (Followers: 2)
Freshwater Reviews     Full-text available via subscription   (Followers: 3)
Freshwater Science     Full-text available via subscription   (Followers: 6)
Frontiers in Ecology and Evolution     Open Access   (Followers: 2)
Frontiers in Evolutionary Neuroscience     Open Access   (Followers: 1)
Frontiers in Life Science     Hybrid Journal  
Frontiers in Marine Science     Open Access  
Frontiers in Neurogenesis     Open Access  
Frontiers in Neuroprosthetics     Open Access  
Frontiers of Biogeography     Open Access   (Followers: 1)
Frontiers of Biology     Hybrid Journal   (Followers: 1)
Frontiers of Environmental Science & Engineering     Hybrid Journal   (Followers: 3)
Fruits     Full-text available via subscription  
Functional & Integrative Genomics     Hybrid Journal   (Followers: 5)
Fundamental and Applied Limnology / Archiv für Hydrobiologie     Full-text available via subscription   (Followers: 1)
Fungal Biology     Hybrid Journal   (Followers: 4)
Fungal Biology Reviews     Full-text available via subscription   (Followers: 4)
Fungal Diversity     Hybrid Journal   (Followers: 2)

  First | 1 2 3 4 5 6 7 8 | Last

Journal Cover 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  [2563 journals]   [SJR: 0.828]   [H-I: 39]
  • Clostridium difficile infection among immunocompromised patients in Rio de
           Janeiro - Brazil and detection of moxifloxacin resistance in a ribotype
           014 strain
    • Abstract: Publication date: Available online 5 June 2014
      Author(s): Danielle Angst Secco , Ilana Teruszkin Balassiano , Renata Ferreira Boente , Karla Rodrigues Miranda , Jon Brazier , Val Hall , Joaquim dos Santos-Filho , Leandro Araujo Lobo , Simone Aranha Nouér , Regina Maria Cavalcanti Pilotto Domingues
      Clostridium difficile is a Gram-positive spore forming anaerobic bacterium, often associated with nosocomial diarrhea and pseudomembranous colitis. The acquisition of this organism occurs primarily in hospitals through accidental ingestion of spores, and its establishment and proliferation in the colon results from the removal of members of the normal intestinal flora during or after antibiotic therapy. In this study, stool samples from patients admitted to the University Hospital Clementino Fraga Filho (HUCCF / UFRJ) were screened for C. difficile toxins with an ELISA test and cultured with standard techniques for C. difficile isolation. A total of 74 stool samples were collected from patients undergoing antibiotic therapy between August 2009 and November 2010, only two (2,7%) were positive in the ELISA test and culture. A third isolate was obtained from a negative ELISA test sample. All cases of CDI were identified in patients with acute lymphoid or myeloid leukemia. Genotypic and phenotypic characterization showed that all strains carried toxins A and B genes, and belonged to PCR-ribotypes 014, 043 and 046. The isolated strains were sensitive to metronidazole and vancomycin, and resistant to ciprofloxacin and levofloxacin. Resistance to moxifloxacin, was present in the strain from PCR-ribotype 014, that showed an amino acid substitution in gyrB gene (Asp 426 → Asn). This is the first time that this mutation in a PCR-ribotype 014 strain has been described in Brazil.

      PubDate: 2014-06-06T14:44:06Z
  • Porphyromonas gingivalis stimulates IL-6 and IL-8 secretion in GMSM-K,
           HSC-3 and H413 oral epithelial cells
    • Abstract: Publication date: Available online 1 June 2014
      Author(s): Michael Yee , Shawn Kim , Pushpinder Sethi , Nejat Düzgüneş , Krystyna Konopka
      Introduction Infection of oral epithelial cells with periodontopathogenic bacteria results in the production of pro-inflammatory cytokines involved in the initiation and progression of periodontal disease. The purpose of this study was to examine the release of interleukin (IL)-6 and IL-8 by oral epithelial cells after exposure to Porphyromonas gingivalis. Methods Non-tumor-derived, immortalized human GMSM-K cells, and human oral squamous cell carcinoma, HSC-3 and H413 cells, were co-cultured with live and heat-inactivated P. gingivalis 2561 (ATCC 33277) and W83 (ATCC BAA-308™). IL-6 and IL-8 were quantified in the culture supernatants after 6 and 24 h. Results The basal levels of both cytokines and the responses to P. gingivalis were strongly dependent on cell type. GMSM-K cells produced less IL-8 than HSC-3 and H413 cells. Live P. gingivalis induced significant IL-6 and IL-8 secretion in GMSM-K and HSC-3 cells, and heat-inactivation of bacteria enhanced greatly IL-6 and IL-8 stimulation in these cells. Uninfected H413 cells produced high levels of IL-6 and IL-8, but were not responsive to live P. gingivalis; heat-inactivated P. gingivalis up-regulated IL-6 and IL-8 secretion in these cells. Conclusions Since base-line secretion of IL-6 and IL-8, and responses to P. gingivalis depend on the cell type, conclusions on the responses to P. gingivalis should not be based on studies with a single cell type.

      PubDate: 2014-06-06T14:44:06Z
  • Clostridium perfringens and Clostridium difficile in cooked beef sold in
           Côte d’Ivoire and their antimicrobial susceptibility
    • Abstract: Publication date: Available online 2 June 2014
      Author(s): Kra Athanase Kouassi , Adjéhi Thomas Dadie , Kouadio Florent N’Guessan , Koffi Marcellin Dje , Yao Guillaume Loukou
      The aim of this study was to evaluate the prevalence of Clostridium difficile and Clostridium perfringens in cooked beef sold in the streets in Côte d’Ivoire and their antimicrobial susceptibility. A total of 395 kidney and flesh samples of cooked beef were collected from vendors at Abidjan and subjected to C. difficile and C. perfringens isolation and identification by using biochemical tests, API 20A system and PCR detection. Subsequently, the antimicrobial susceptibility test was performed for confirmed isolates. Our results showed the prevalence of 12.4% for C. difficile (11.04% in kidney and 13.45% in flesh) and 5.06% for C. perfringens (2.32% in kidney and 7.17% in flesh). Metronidazole and vancomycin remained the most potent antimicrobial agents against C. difficile while metronidazole and penicillin G were the most potent agents against C. perfringens. The resistance rates to tetracycline, doxycycline, chloramphenicol and erythromycin against C. difficile and C. perfringens isolates ranged from 2.05% to 8.16% and from 20% to 50%, respectively. Among all antimicrobial agents tested against C. difficile, percentages of resistance to quinolones ciprofloxacin, norfloxacin and nalidixic acid as well as to gentamicin and cefotaxime were the highest. Eight resistant phenotypes were defined for C. difficile isolates and eleven resistant phenotypes for C. perfringens isolates. Clindamycin/gentamicin/cefotaxime/ciprofloxacin/norfloxacin/nalidixic acid resistance was the most common phenotype for C. difficile (55.10% of isolates) while norfloxacin/nalidixic acid resistance was the most common phenotype for C. perfringens (20% of isolates).

      PubDate: 2014-06-06T14:44:06Z
  • Antifungal activity and identification of Lactobacilli, isolated from
           traditional dairy product “katak”
    • Abstract: Publication date: Available online 1 June 2014
      Author(s): Rositsa Tropcheva , Dilyana Nikolova , Yana Evstatieva , Svetla Danova
      Filamentous moulds are the main spoilage microorganisms, responsible for significant economic losses and several healthy risks in human food chain. The lactic acid bacteria (LAB), especially lactobacilli could be a natural antagonist of these dangerous organisms. In Bulgaria, a very limited data exists on the antifungal activity of LAB microbiota of fermented dairy products. In the present study, four active strains were isolated from traditional fermented curd/yogurt-like product “katak”, produced in Bulgaria from centuries. The new isolates KR3, KR4, KR51 and KR53 were identified by API 50 CH biochemical test and different molecular methods (species-specific PCR, RAPD-PCR and 16S rDNA sequence analysis) as Lactobacillus brevis. According to our knowledge, this is the first data on the molecular characterization of the Lactobacillus microbiota of “katak”. A broad spectrum of antifungal activity of the four L. brevis KR strains against test-cultures representatives of carcinogenic, toxigenic, deteriorative and allergenic fungi from the genera Aspergillus, Fusarium, Penicillium and Trichoderma was estimated. Strains L. brevis KR3, KR4 and KR51 completely suppress the growth of Penicillium claviforme, Aspergillus awamori and Aspergillus niger. With regard to Aspergillus flavus and Trichoderma viride, a lower and strain-specific inhibitory activity was observed. The antifungal activity of our new L. brevis isolates seems to be a promising advantage of these four strains, suggesting their potential applications in different food technologies as bio-preservative agents against moulds.

      PubDate: 2014-06-06T14:44:06Z
  • A combined metabolomic and phylogenetic study reveals putatively prebiotic
           effects of high molecular weight arabino-oligosaccharides when assessed by
           in vitro fermentation in bacterial communities derived from humans
    • Abstract: Publication date: Available online 4 June 2014
      Author(s): Karolina Sulek , Louise Kristine Vigsnaes , Line Rieck Schmidt , Jesper Holck , Henrik Lauritz Frandsen , Jørn Smedsgaard , Thomas Hjort Skov , Anne S. Meyer , Tine Rask Licht
      Prebiotic oligosaccharides are defined by their selective stimulation of growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial for health. However, apart from the short chain fatty acids, little is known about bacterial metabolites created by fermentation of prebiotics, and the significance of the size of the oligosaccharides remains largely unstudied. By in vitro fermentations in human fecal microbial communities (derived from six different individuals), we studied the effects of high-mass (HA, >1 kDa), low-mass (LA, <1 kDa) and mixed (BA) sugar beet arabino-oligosaccharides (AOS) as carbohydrate sources. Fructo-oligosaccharides (FOS) were included as reference. The changes in bacterial communities and the metabolites produced in response to incubation with the different carbohydrates were analyzed by quantitative PCR (qPCR) and Liquid Chromatography–Mass Spectrometry (LC–MS), respectively. All tested carbohydrate sources resulted in a significant increase of Bifidobacterium spp. between 1.79 fold (HA) and 1.64 fold (FOS) in the microbial populations after fermentation, and LC–MS analysis suggested that the bifidobacteria contributed to decomposition of the arabino-oligosaccharide structures, most pronounced in the HA fraction, resulting in release of the essential amino acid phenylalanine. Abundance of Lactobacillus spp. correlated with the presence of a compound, most likely a flavonoid, indicating that lactobacilli contribute to release of such health-promoting substances from plant structures. Additionally, the combination of qPCR and LC–MS revealed a number of other putative interactions between intestinal microbes and the oligosaccharides, which contributes to the understanding of the mechanisms behind prebiotic impact on human health.

      PubDate: 2014-06-06T14:44:06Z
  • Flux analysis of the human proximal colon using Anaerobic Digestion Model
    • Abstract: Publication date: Available online 28 May 2014
      Author(s): Anne Marieke Motelica-Wagenaar , Arjen Nauta , Ellen G.H.M. van den Heuvel , Robbert Kleerebezem
      The colon can be regarded as an anaerobic digestive compartment within the gastro intestinal tract (GIT). An in silico model simulating the fluxes in the human proximal colon was developed on basis of the anaerobic digestion model 1 (ADM1), which is traditionally used to model waste conversion to biogas. Model calibration was conducted using data from in vitro fermentation of the proximal colon (TIM-2), and, amongst others, supplemented with the bio kinetics of prebiotic galactooligosaccharides (GOS) fermentation. The impact of water and solutes absorption by the host was also included. Hydrolysis constants of carbohydrates and proteins were estimated based on total short chain fatty acids (SCFA) and ammonia production in vitro. Model validation was established using an independent dataset of a different in vitro model: an in vitro three-stage continuous culture system. The in silico model was shown to provide quantitative insight in the microbial community structure in terms of functional groups, and the substrate and product fluxes between these groups as well as the host, as a function of the substrate composition, pH and the solids residence time (SRT). The model confirms the experimental observation that methanogens are washed out at low pH or low SRT-values. The in silico model is proposed as useful tool in the design of experimental setups for in vitro experiments by giving insight in fermentation processes in the proximal human colon.

      PubDate: 2014-05-30T20:38:09Z
  • Development and evaluation of new primers for PCR-based identification of
           Prevotella intermedia
    • Abstract: Publication date: Available online 26 May 2014
      Author(s): Yanbin Zhou , Dali Liu , Yiwei Wang , Cailian Zhu , Jingping Liang , Rong Shu
      The aim of this study was to develop new Prevotella intermedia-specific PCR primers based on the 16S rRNA. The new primer set, Pi-192 and Pi-468, increased the accuracy of PCR-based P. intermedia identification and could be useful in the detection of P. intermedia as well as epidemiological studies on periodontal disease.

      PubDate: 2014-05-30T20:38:09Z
  • Recent evolution of antibiotic resistance in the anaerobes as compared to
           previous decades
    • Abstract: Publication date: Available online 26 May 2014
      Author(s): Lyudmila Boyanova , Rossen Kolarov , Ivan Mitov
      Evolution of antibiotic resistance in the anaerobes was reviewed using recent data covering 2000-2013 as compared to previous years. All studies reported growing moxifloxacin resistance in Bacteroides/Parabacteroides spp. in Europe and USA and in Clostridium difficile in Europe. In half or more studies, the resistance rates in Bacteroides/Parabacteroides spp. to amoxicillin-clavulanate or ampicillin-sulbactam and clindamycin rose. In some studies, an increase in resistance was found in Bacteroides/Parabacteroides spp. to cefoxitin/cefotetan and carbapenems, in Prevotella spp. to penicillins, in anaerobic cocci to clindamycin and in Bacteroides/Parabacteroides spp. and C. difficile to metronidazole. Decreasing resistance was also observed, e.g. in Bacteroides/Parabacteroides spp. to cephalosporins, in Prevotella spp. and C. difficile to tetracyclines and in C. difficile to rifampin. No resistance changes were found to tigecycline, in Bacteroides/Parabacteroides spp. to chloramphenicol and in C. difficile to vancomycin. Factors influencing the resistance were the species, ribotype, country, hospital centre, antibiotic consumption and specimen type. In conclusion, the antibiotic resistance changes in the anaerobes are diverse and dynamic. Regular national surveys of resistance and both anaerobic microbiology and susceptibility testing of the isolates become more and more valuable.

      PubDate: 2014-05-30T20:38:09Z
  • The relationship between bifidobacteria and allergic asthma and/or
           allergic dermatitis: A prospective study of 0-3 years-old children in
    • Abstract: Publication date: Available online 28 May 2014
      Author(s): Hatice Kubra Akay , Hrisi Bahar Tokman , Nevin Hatipoglu , Huseyin Hatipoglu , Rengin Siraneci , Mehmet Demirci , Baris Ata Borsa , Pelin Yuksel , Asiye Karakullukcu , Achille Aime Kangaba , Serhat Sirekbasan , Sibel Aka , Muzeyyen Mamal Torun , Bekir S. Kocazeybek
      Bifidobacteria are beneficial bacteria for humans. These bacteria are particularly effective at protecting against infectious diseases and modulating the immune response. It was shown that in newborns, the fecal distribution of the colonizing Bifidobacterium species influences the prevalence of allergic diseases. This study aimed to compare the faecal Bifidobacterium species of allergic children to those of healthy children to detect species level differences in faecal distribution. Stool samples were obtained from 99 children between 0 and 3 years of age whose clinical symptoms and laboratory reports were compatible with atopic dermatitis and allergic asthma. Samples were also obtained from 102 healthy children who were similar to the case group with respect to age and sex. Bifidobacteria were isolated by culture and identified at the genus level by API 20 A. In addition, 7 unique species-specific primers were used for the molecular characterization of bifidobacteria. The McNemar test was used for statistical analyses, and p < 0.05 was accepted as significant. Bifidobacterium longum was detected in 11 (11.1%) of the allergic children and in 31 (30.3%) of the healthy children. Statistical analysis revealed a significant difference in the prevalence of Bifidobacterium longum between these two groups (X2: 11.2, p< 0.001). However, no significant differences in the prevalence of other Bifidobacterium species were found between faecal samples from healthy and allergic children. (p> 0.05). The significant difference in the isolation of B. longum from our study groups suggests that this species favours the host by preventing the development of asthma and allergic dermatitis. Based on these results, we propose that the production of probiotics in accordance with country-specific Bifidobacterium species densities would improve public health. Thus, country-specific prospective case-control studies that collect broad data sets are needed.

      PubDate: 2014-05-30T20:38:09Z
  • The influence of oral Veillonella species on biofilms formed by
           Streptococcus species
    • Abstract: Publication date: Available online 23 May 2014
      Author(s): Izumi Mashima , Futoshi Nakazawa
      Oral Veillonella, V. atypica, V. denticariosi, V. dispar, V. parvula, V. rogosae, and V. tobetsuensis are known as early colonizers in oral biofilm formation. To investigate the role of oral Veillonella, biofilms formed by the co-culture of Streptococcus gordonii, S. mutans, S. salivarius, or S. sanguinis, with oral Veillonella were examined at the species level. The amount of biofilm formed by S. mutans, S. gordonii, and S. salivarius in the presence of the six Veillonella species was greater than that formed in the control experiments, with the exception of S. mutans with V. dispar. In contrast, in the case of biofilm formation by S. sanguinis, the presence of Veillonella species reduced the amount of the biofilm, with the exception of V. parvula and V. dispar. The time-dependent changes in the amount of biofilm and the number of planktonic cells were grouped into four patterns over the 24 combinations. Only that of S. gordonii with V. tobetsuensis showed a unique pattern. These results indicate that the mode of action of this combination differed from that of the other combinations with respect to biofilm formation. It is possible that there may be several factors involved in the interaction between Streptococcus and Veillonella species.

      PubDate: 2014-05-24T12:53:22Z
  • Antagonistic mechanisms of synbiosis between Lactobacillus plantarum
           CIF17AN2 and green banana starch in the proximal colon model challenged
           with Salmonella Typhimurium
    • Abstract: Publication date: Available online 21 May 2014
      Author(s): Supansa Uraipan , Patrizia Brigidi , Tipparat Hongpattarakere
      Antagonistic mechanisms of Lactobacillus plantarum CIF17AN2 (an infant isolate), saba starch, and their synbiotic combination against Salmonella Typhimurium SA2093 were evaluated. The anti-Salmonella activity was investigated under the competitive niche of fecal microbiota using the simulated proximal colon model. The alterations of the dominant fecal microbiota and beneficial bacteria were also displayed using FISH and PCR-DGGE techniques. Lactobacillus plantarum CIF17AN2 exhibited anti-Salmonella mechanisms through secretion of antimicrobial compounds, adhesion ability and competitive adhesion to mucin and HT-29 cell line. However, the Salmonella inhibition was significantly reduced in the presence of human fecal microflora. The combination of saba starch with L. plantarum CIF17AN2 showed the greatest inhibition against Sal. Typhimurium SA2093 in the simulated colon model. The enhancement of anti-Salmonella activity due to the addition of saba starch corresponded to a significant decrease in pH and an increase of lactic acid and short chain fatty acids. According to PCR-DGGE analysis, L. plantarum CIF17AN2 was able to survive and effectively compete with fecal microflora. Saba starch supplement modified bifidobacterial profile but had a slight impact on the profile of lactic acid bacteria. This prebiotic approach alleviated the nutrient limitation in the proximal colon model leading to the selective stimulation of beneficial lactobacilli and bifidobacteria, hence the enhancement of anti-Salmonella activity.

      PubDate: 2014-05-24T12:53:22Z
  • Effect of Bifidobacterium animalis B/12 administration in healthy dogs
    • Abstract: Publication date: Available online 15 May 2014
      Author(s): Viola Strompfová , Monika Pogány Simonová , Soňa Gancarčíková , Dagmar Mudroňová , Jana Farbáková , Aladár Maďari , Andrea Lauková
      Bifidobacterium species constitute the most frequently used health-enhancing bacteria in functional foods or probiotic products, and most of their health benefits have been demonstrated in human or mice studies. However, knowledge of the effects of these bacteria in the canine organism is very limited. In this study, the canine-derived strain B. animalis B/12 (109 CFU) was tested for its effects on faecal microbiota, faecal characteristics, faecal organic acid concentrations, blood biochemistry, haematological and immunological parameters in healthy dogs (C-control, BA- B.animalis B/12 group, 10 dogs in each). The experiment lasted for 49 days with a 14-day treatment period (sample collection at days 0, 7, 14, 21, 28, and 49). A significantly higher population of lactic acid bacteria was detected (day 7) while the counts of coliform bacteria were lower in faeces of the BA group (days 14, 21, 28, 49) compared to control group C. Faecal concentrations of acetic (day 7, 21, 28, 49), acetoacetic (7-49) and valeric acid (14) were higher in contrast to formic acid (day 7-21), which was decreased after the treatment. In blood serum, significantly lower concentrations of triglyceride (day 14) and albumin (day 14, 28, 49) and significantly higher levels of alanine aminotrasferase (day 14) and alkaline phosphatase (day 14, 28) were observed in the BA dogs. The phagocytic activity of leukocytes (especially of neutrophils) was higher in dogs after 14-day consumption of B/12 strain (day 14). The results show that many of these effects could also still be recorded several weeks after the treatment period.

      PubDate: 2014-05-19T06:02:24Z
  • Editorial board
    • Abstract: Publication date: June 2014
      Source:Anaerobe, Volume 27

      PubDate: 2014-05-14T03:51:14Z
  • Probiotic potential and biotherapeutic effects of newly isolated vaginal
           Lactobacillus acidophilus 36YL strain on cancer cells
    • Abstract: Publication date: Available online 10 May 2014
      Author(s): Yousef Nami , Norhafizah Abdullah , Babak Haghshenas , Dayang Radiah , Rozita Rosli , Ahmad Yari Khosroushahi
      Lactobacillus acidophilus is categorized as a probiotic strain because of its beneficial effects in human health and prevention of disease transmission.This study is aimed to characterize the probiotic potential of L. acidophilus 36YL originally isolated from the vagina of healthy and fertile Iranian women. The L. acidophilus 36YL strain was identified using 16S rDNA gene sequencing and characterized by biochemical methodologies, such as antibiotics susceptibility, antimicrobial activity, and acid and bile resistance. The bioactivity of the secretion of this strain on four human cancer cell lines (AGS, HeLa, MCF-7, and HT-29) and one normal cell line (HUVEC) was evaluated by cytotoxicity assay and apoptosis analysis. This newly isolated strain was found to exhibit notable probiotic properties, such as admirable antibiotic susceptibility, good antimicrobial activity, and favorable resistance to acid and bile salt. The results of bioactivity assessment demonstrated acceptable anticancer effects on the four tested cancer cell lines and negligible side effects on the assayed normal cell line. Our findings revealed that the anticancer effect of L. acidophilus 36YL strain secretions depends on the induction of apoptosis in cancer cells. L. acidophilus 36YL strain is considered as a nutraceutical alternative or a topical medication with a potential therapeutic index because of the absence of cytotoxicity to normal cells, but effective toxicity to cancer cell lines.

      PubDate: 2014-05-14T03:51:14Z
  • In vitro effect of antibiotics on biofilm formation by B. fragilis group
           strains isolated from intestinal microbiota of dogs and their
           antimicrobial susceptibility
    • Abstract: Publication date: Available online 4 May 2014
      Author(s): Janice Oliveira Silva , Ana Catarina Martins Reis , Carlos Quesada-Gómez , Adriana Queiroz Pinheiro , Rosemary Souza Freire , Reinaldo Barreto Oriá , Cibele Barreto Mano de Carvalho
      The Bacteroides fragilis group strains colonize the intestinal tract of dogs as commensal bacteria. Nevertheless, they can be opportunistic pathogens responsible of significant morbidity and mortality rates in dogs, like in oral infections, abscesses and wound infections. The purpose of this study was to evaluate antimicrobial susceptibility in B. fragilis strains isolated from dogs intestinal microbiota and to evaluate the effect of subinhibitory concentrations of some antimicrobials on biofilm formation. A total of 30 B. fragilis group strains were tested for susceptibility to ten antimicrobial agents by broth microdilution method. Thirteen B. fragilis strains were tested for biofilm formation and the biofilm producer strains were chosen to evaluate the effect of subinhibitory concentrations of six antimicrobials on biofilm formation. The isolates were susceptible to amoxicillin-clavulanic acid, metronidazole, imipenem and chloramphenicol. Tetracycline and clindamycin were active against 50% and 33% of the strains, respectively. When biofilm-forming strains were grown in the presence of sub-MICs of imipenem and metronidazole, the inhibition of biofilm formation was observed. In contrast, enrofloxacin at ½ MIC caused a significant increase in biofilm formation in two of four strains examined. In conclusion, the B. fragilis group strains isolated were susceptible to most of the antimicrobials tested and the sub-MIC concentrations of imipenem, metronidazole and clindamycin were able to inhibit the biofilm formation.

      PubDate: 2014-05-09T06:25:21Z
  • Occurrence of Clostridium difficile PCR-ribotype 027 and it’s
           closely related PCR-ribotype 176 in hospitals in Poland in 2008-2010
    • Abstract: Publication date: Available online 2 May 2014
      Author(s): Piotr Obuch-Woszczatyński , Dominika Lachowicz , Anna Schneider , Anna Mól , Jolanta Pawłowska , Ewa Ożdżeńska-Milke , Piotr Pruszczyk , Dorota Wultańska , Grażyna Młynarczyk , Celine Harmanus , Ed J. Kuijper , Alex van Belkum , Hanna Pituch
      Since 2003, a rising incidence of Clostridium difficile infection (CDI) in North America and Europe has coincided with outbreaks of C. difficile PCR ribotype 027. This ribotype was not observed in Poland until 2008. In the period 2008–2010, outbreaks of antibiotic-associated diarrhoea occurred in three different hospitals in Poland. Of 30 C. difficile isolates available for microbiological characterisation, 17 (56%) were positive for binary toxin genes and belonged to PCR ribotype 027 (n = 7) and its closely related PCR ribotype 176 (n = 10). All 17 binary toxin–positive C. difficile strains demonstrated high-level resistance to fluoroquinolones (minimum inhibitory concentration (MIC) ≥ 32 mg/L), including ciprofloxacin, gatifloxacin, and moxifloxacin, as well as erythromycin and clindamycin (MIC ≥ 256 mg/L for both). Of 14 patients from whom clinical information was available, 50% had a severe form of CDI, defined by fever (>38.5°C), decreased kidney function, and high leukocyte count. We conclude that outbreaks of CDI associated with hypervirulent strains belonging to PCR ribotypes 027 and 176 occurred in hospitals in Poland. Further studies evaluating the clinical impact of type 176 are urgently needed.

      PubDate: 2014-05-04T07:20:37Z
  • Dynamics of microbial communities in untreated and autoclaved food waste
           anaerobic digesters
    • Abstract: Publication date: Available online 1 May 2014
      Author(s): Lucia Blasco , Minna Kahala , Elina Tampio , Satu Ervasti , Teija Paavola , Jukka Rintala , Vesa Joutsjoki
      This study describes the microbial community richness and dynamics of two semi-continuously stirred biogas reactors during a time-course study of 120 days. The reactors were fed with untreated and autoclaved (160°C, 6.2 bar) food waste. The microbial community was analyzed using a bacteria- and archaea-targeting 16S rRNA gene-based Terminal-Restriction Fragment Length Polymorphism (T-RFLP) approach. Compared with the archaeal community, the structures and functions of the bacterial community were found to be more complex and diverse. With the principal coordinates analysis it was possible to separate both microbial communities with 75 and 50% difference for bacteria and archaea, respectively, in the two reactors fed with the same waste but with different pretreatment. Despite the use of the same feeding material, anaerobic reactors showed a distinct community profile which could explain the differences in methane yield (2-17%). The community composition was highly dynamic for bacteria and archaea during the entire studied period. This study illustrates that microbial communities are dependent on feeding material and that correlations among specific bacterial and archaeal T-RFs can be established.

      PubDate: 2014-05-04T07:20:37Z
  • Potential of goat probiotic to bind mutagens
    • Abstract: Publication date: Available online 29 April 2014
      Author(s): Ana Lidia Apás , Silvia Nelina González , Mario Eduardo Arena
      The mutagen binding ability of the goat probiotics (Lactobacillus reuteri DDL 19, Lactobacillus alimentarius DDL 48, Enterococcus faecium DDE 39, and Bifidobacterium bifidum DDBA) was evaluated. The oral administration of these probiotics reduced fecal mutagens and intestinal cancer markers in goats. Secondly, the effects of probiotics against the mutagenesis induced by sodium azide (SA), and Benzopyrene (B[α]P) by performing the modified Ames test using Salmonella typhimurium TA 100 was investigated. The capacity to bind benzopyrene and the stability of the bacterial-mutagen complex was analyzed by HPLC. The dismutagenic potential against both mutagens was proportional to probiotic concentration. Results showed that probiotic antimutagenic capacity against SA was ranging from 13 to 78%. The mixture of four goat probiotics (MGP) displayed higher antimutagenic activity against SA than any individual strains at the same cell concentration. This study shows that the highest diminution of mutagenicity in presence of B[α]P (74%) was observed in presence of MGP. The antimutagenic activity of nearly all the individual probiotic and the MGP were in concordance with the B[α]P binding determined by HPLC. According to our results, the B[α]P binding to probiotic was irreversible still after being washed with DMSO solution. The stability of the toxic compounds-bacterial cell binding is a key consideration when probiotic antimutagenic property is evaluated. MGP exhibits the ability to bind and detoxify potent mutagens, and this property can be useful in supplemented foods for goats since it can lead to the removal of potent mutagens and protect and enhance ruminal health and hence food safety of consumers.

      PubDate: 2014-04-29T06:44:24Z
  • Towards molecular biomarkers for biogas production from
           lignocellulose-rich substrates
    • Abstract: Publication date: Available online 28 April 2014
      Author(s): Michael Lebuhn , Angelika Hanreich , Michael Klocke , Andreas Schlüter , Christoph Bauer , Carmen Marín Pérez
      Biogas production from lignocellulose-rich agricultural residues is gaining increasingly importance in sustainable energy production. Hydrolysis/acidogenesis (H/A) of lignocellulose as the initial rate limiting step deserves particular optimization. A mixture of straw/hay was methanized applying two-phase digester systems with an initial H/A reactor and a one-stage system at different, meso- and thermophilic temperatures. H/A was intensified with increasing pH-values and increasing temperature. H/A fermenters, however, were prone to switch to methanogenic systems at these conditions. Substrate turnover was accelerated in the bi-phasic process but did not reach the methanation efficiency of the single-stage digestion. There was no indication that 2 different cellulolytic inocula could establish in the given process. Bacterial communities were analyzed applying conventional amplicon clone sequencing targeting the hypervariable 16S rRNA gene region V6 – V8 and by metagenome analyses applying direct DNA pyrosequencing without a PCR step. Corresponding results suggested that PCR did not introduce a bias but offered better phylogenetic resolution. Certain Clostridium IV and Prevotella members were most abundant in the H/A system operated at 38°C, certain Clostridium III and Lachnospiraceae bacteria in the 45°C, and certain Clostridium IV and Thermohydrogenium/Thermoanaerobacterium members in the 55°C H/A system. Clostridium III representatives, Lachnospiraceae and Thermotogae dominated in the thermophilic single-stage system, in which also a higher portion of known syntrophic acetate oxidizers was found. Specific (RT-)qPCR systems were designed and applied for the most significant and abundant populations to assess their activity in the different digestion systems. The RT-qPCR results agreed with the DNA based community profiles obtained at the different temperatures. Up to 1012 16S rRNA copies * mL-1 were determined in H/A fermenters with prevalence of rRNA of a Ruminococcaceae subgroup. Besides, Thermohydrogenium/Thermoanaerobacterium rRNA prevailed at thermophilic and Prevotellaceae rRNA at mesophilic conditions. The developed (RT)-qPCR systems can be used as biomarkers to optimize biogas production from straw/hay and possibly other lignocellulosic substrates.

      PubDate: 2014-04-29T06:44:24Z
  • Anti stress proteins produced by Bacteroides thetaiotaomicron after
           nutrient starvation
    • Abstract: Publication date: Available online 28 April 2014
      Author(s): Anne-Cécile Hochart-Behra , Hervé Drobecq , Mélissa Tourret , Luc Dubreuil , Josette Behra-Miellet
      Bacteroides thetaiotaomicron may be one of the most adaptable intestinal bacteria due to its complex genome. Known to be an opportunistic pathogenic anaerobe, B. thetaiotaomicron has recently been described as a symbiont with anti-inflammatory properties. In this study, peptide mass finger printing technique was used to identify the stress proteins (maybe anti stress proteins for the host) extracted from B. thetataiotaomicron grown under nutrient starvation (without heme, blood or bile) prior to be placed in an aerobic solution containing a mild non-ionic detergent derived from cholic acid. We focus here on proteins related to stress, knowing that superoxide dismutase was previously identified in the extract. In parallel, the morphology of the bacterial cells was observed using electronic microscopy before and after the extraction process. The effective antioxidant effect of the extract was evaluated in vitro against hydrogen peroxide. This work highlights the B. thetaiotaomicron ability to produce a large amount of stress proteins and to remain viable during the extraction. Budding vesicles were observed on its cell wall. The extraction process did not exceed 20 h in order to preserve the bacterial viability that decreased significantly after 24 h in preliminary studies. In our experimental conditions, an inhibitory effect of the extract was found against hydrogen peroxide. Animal models of inflammation will later check in vivo if this extract of anti stress proteins is able to counter the respiratory burst beginning an inflammation process.
      Graphical abstract image

      PubDate: 2014-04-29T06:44:24Z
  • 8th International Symposium on Anaerobic Microbiology (ISAM 8): No oxygen
           - still vigorous Innsbruck, Austria, June 12-15, 2013
    • Abstract: Publication date: Available online 29 April 2014
      Author(s): Heribert Insam , Sabine Marie Podmirseg , Andreas Otto Wagner , Jiri Simunek

      PubDate: 2014-04-29T06:44:24Z
  • Ventriculoperitoneal shunt infection caused by Bifidobacterium breve
    • Abstract: Publication date: Available online 19 April 2014
      Author(s): Nuntra Suwantarat , Mark Romagnoli , Teresa Wakefield , Karen C. Carroll
      Bifidobacterium breve is a rare cause of human infections. Previously, bacteremia and meningitis caused by this organism linked to probiotic use have been reported in a neonate. We report the first case of a ventriculoperitoneal shunt infection caused by B. breve in an adult without a history of probiotic use.

      PubDate: 2014-04-24T05:14:44Z
  • International Typing Study of Clostridium difficile
    • Abstract: Publication date: Available online 21 April 2014
      Author(s): Carl E. Manzo , Michelle M. Merrigan , Stuart Johnson , Dale N. Gerding , Thomas V. Riley , Joseph Silva Jr. , Jon S. Brazier
      We report the results of an international Clostridium difficile typing study to cross reference strain designations for seven typing methodologies and facilitate inter-laboratory communication. Four genotypic and three phenotypic methods were used to type 100 isolates and compare the results to 39 PCR ribotypes identified among the collection.

      PubDate: 2014-04-24T05:14:44Z
  • Antimicrobial potential of bacteriocin producing Lysinibacillus jx416856
           against foodborne bacterial and fungal pathogens, isolated from fruits and
           vegetable waste
    • Abstract: Publication date: Available online 13 April 2014
      Author(s): Varish Ahmad , A.N. Muhammad Zafar Iqbal , Mohd Haseeb , Mohd Sajid Khan
      In this study, antimicrobial potential, some probiotics properties and bacteriocin nature of Lysinibacillus, isolated from fruits and vegetable waste were evaluated. For this, 125 Lactobacillus isolates were tested against foodborne bacterial and fungal pathogens. Among these, an isolated Bacillus spp. showed significant aggregation-co-aggregation probiotics properties and potentially inhibits the foodborne gram positive microbial pathogens such as Staphylococcus aureus, (22 mm ZOI), Staphylococcus epedermidis and Bacillus cereus (18 mm). Phenotypically and molecularly it was identified as Lysinibacillus (NCBI accession no. JX416856) and it was found closest to Lysinibacillus fusiformis, Lysinibacillus sphaericus and Lysinibacillus xylanilyticus. Physico-biochemically, it was found to be negative for amylase, protease, gelatinase, nitrate reductase and urease while positive for catalase. The diagnostic fatty acid was 22;2 (3.51). The growth conditions and bacteriocin activity were found to be optimum with MRS media at pH 7–10, Temperature 35–40 °C and salt tolerance at 1–3%. Eventually its production was optimized with MRS broth at pH 7.6, 37 °C, for 36 h in shaking conditions at the rate of 100 rpm. Active bacteriocin was isolated at 60% ammonium sulfate precipitation. The molecular weight of given bacteriocin was found to be nearly 25–35 kDa by SDS-PAGE. Based on physico- biochemical properties, the isolated bacteriocin was to be categories in class II bacteriocin. The bacteriocin was found to be stable in the range of 4–80 °C temperature, 6–10 pH and even in the presence of surfactant (such as SDS and Tween 80). However, proteases like pepsin and trypsin were found to degrade the bacteriocin. Collectively, the broad spectrum inhibitory potential and physical stability offered the antimicrobial potential to Lysinibacillus, and its relevant bacteriocin might be used as an alternative food preservative or therapeutic agent to control spoilage of different food products.

      PubDate: 2014-04-18T16:03:31Z
  • Reactor performance of a 750 m3 anaerobic digestion plant: Varied
           substrate input conditions impacting methanogenic community
    • Abstract: Publication date: Available online 13 April 2014
      Author(s): Andreas Otto Wagner , Cornelia Malin , Philipp Lins , Gudrun Gstraunthaler , Paul Illmer
      A 750 m3 anaerobic digester was studied over a half year period including a shift from good reactor performance to a reduced one. Various abiotic parameters like volatile fatty acids (VFA) (formic-, acetic-, propionic-, (iso-)butyric-, (iso-)valeric-, lactic acid), total C, total N, NH4 -N, and total proteins, as well as the organic matter content and dry mass were determined. In addition several process parameters such as temperature, pH, retention time and input of substrate and the concentrations of CH4, H2, CO2 and H2S within the reactor were monitored continuously. The present study aimed at the investigation of the abundance of acetogens and total cell numbers and the microbial methanogenic community as derived from PCR-dHPLC analysis in order to put it into context with the determined abiotic parameters. An influence of substrate quantity on the efficiency of the anaerobic digestion process was found as well as a shift from a hydrogenotrophic in times of good reactor performance towards an acetoclastic dominated methanogenic community in times of reduced reactor performance. After the change in substrate conditions it took the methano-archaeal community about 5–6 weeks to be affected but then changes occurred quickly.

      PubDate: 2014-04-18T16:03:31Z
  • Relationship between gastrointestinal dysbiosis and Clostridium botulinum
           in dairy cows
    • Abstract: Publication date: Available online 16 April 2014
      Author(s): Monika Krüger , Awad A. Shehata , Anke Grosse-Herrenthey , Norman Ständer , Wieland Schrödl
      The gastrointestinal tract is a balanced ecosystem that can get out of balance and predisposed to clostridial diseases or other pathological conditions. The objective of the present study was to evaluate the gut microbiota in dairy cows suffering from chronic botulism. Cows were investigated for Clostridium (C.) botulinum in faeces and rumen fluids. In order to study the relationship between botulism and gastrointestinal microbiota, faeces and rumen fluid were tested for bacterial composition using conventional microbiological culture techniques and fluorescence in situ hybridization (FISH). Protozoa were analyzed in rumen fluid microscopically. The presence of C. botulinum was associated with specific changes in the faecal microbiota, especially a significant reduction of total aerobic bacteria, total anaerobic bacteria, enterococci, Clostridium perfringens and yeast and fungi. Also C. botulinum positive rumen fluid had significantly more Bacteroides spp., C. histolyticum group, Alfa- proteobacteria, Gammaproteobacteria, and sulfate-reducing bacteria; as well as significantly fewer Euryaracheota, and the protozoa Epidinium spp. Dasytricha spp., Diplodiniinae spp. and Ophryoscolex spp. In conclusion, C. botulinum is common in dairy cows in Germany but the incidence of botulism is associated with microbial changes and composition in the gastrointestinal tract. Bacteria, yeast and protozoa appear to be crucial in the colonization process; however, the chronology of these events and role of each microbial group needs further evaluation.

      PubDate: 2014-04-18T16:03:31Z
  • Process diagnosis using methanogenic Archaea in maize-fed, trace element
           depleted fermenters
    • Abstract: Publication date: Available online 18 April 2014
      Author(s): Bernhard Munk , Michael Lebuhn
      A mesophilic maize-fed pilot-scale fermenter was severely acidified due to trace element (TE) deficiency. Mainly cobalt (0.07 mg * kg-1 fresh mass (FM)), selenium (0.007 mg * kg-1 FM) and sodium (13 mg * kg-1 FM) were depleted. From this inoculum, three lab-scale flow-through fermenters were operated to analyse micronutrient deficiencies and population dynamics in more detail. One fermenter was supplemented with selenium, one with cobalt, and one served as control. After starvation and recovery of the fermenters, the organic loading rate (OLR) was increased. In parallel, the concentration (Real-Time PCR) of methanogens and their population composition (amplicon sequencing) was determined at the DNA and mRNA level. The parameters Metabolic Quotient (MQ) and cDNA/DNA were calculated to assess the activity of the methanogens. The control without TE supplementation acidified first at an OLR of 4.0 kg volatile solids (VS) * m-3 * d-1 while the singular addition of selenium and of cobalt positively influenced the fermenter stability up to an OLR of 4.5 or 5.0 kg VS * m-3 * d-1, respectively. In the stable process, the methanogenic populations were dominated by probably residual hydrogenotrophic Methanoculleus sp. (DNA-level), but representatives of versatile Methanosarcina sp. were most active (cDNA-level). When the TE supplemented fermenters began to acidify, Methanosarcina spp. were dominant in the whole (DNA-level) and the active (cDNA-level) community. The acidified control fermenter was dominated by Methanobacteriaceae genus IV. Until acidification, the concentration of methanogens increased with higher OLRs. The MQ indicated stress metabolism approximately one month before the TVA/TIC ratio reached a critical level of 0.7, demonstrating its suitability as early warning parameter of process acidification. The development of the cDNA/DNA ratio also reflected the increasing methanogenic activity with higher OLRs. Highest cDNA/DNA values (ca. 2) were obtained at metabolic strain of the methanogens, at the onset of acidification.

      PubDate: 2014-04-18T16:03:31Z
  • The role of the humoral immune response to Clostridium difficile toxins A
           and B in susceptibility to Clostridium difficile Infection: a case-control
    • Abstract: Publication date: Available online 5 April 2014
      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
    • Abstract: Publication date: Available online 1 April 2014
      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
      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
      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
      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
      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
      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
      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
    • Abstract: Publication date: Available online 19 March 2014
      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
      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
      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
      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
      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
      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
      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
      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
      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
  • Detection and partial characterization of a bacteriocin-like substance
           produced by Lactobacillus fermentum CS57 isolated from human vaginal
    • Abstract: Publication date: Available online 21 January 2014
      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
      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
      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
      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
  • Prebiotic effects of almonds and almond skins on intestinal microbiota in
           healthy adult humans
    • Abstract: Publication date: Available online 3 December 2013
      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
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