Read by QxMD icon Read


Vincent Poot, Maaike Hoekstra, Mitchell A A Geleijnse, Mark C M van Loosdrecht, Julio Pérez
Partial nitritation was stably achieved in a bench-scale airlift reactor (1.5L) containing granular sludge. Continuous operation at 20 °C treating low-strength synthetic wastewater (50 mg N-NH4(+)/L and no COD) achieved nitrogen loading rates of 0.8 g N-NH4(+)/(L·d) during partial nitritation. The switch between nitrite-oxidizing bacteria (NOB) repression and NOB proliferation was observed when ammonium concentrations in the reactor were below 2-5 mg N-NH4(+)/L for DO concentrations lower than 4 mg O2/L at 20 °C...
October 11, 2016: Water Research
Campana Raffaella, Luca Casettari, Laura Fagioli, Marco Cespi, Giulia Bonacucina, Wally Baffone
Food safety is a fundamental concern for both consumers and the food industry, especially as the numbers of reported cases of food-associated infections continue to increase. Industrial surfaces can provide a suitable substrate for the development and persistence of bacterial organized in biofilms that represent a potential source of food contamination. The negative consumer perception of chemical disinfectants has shifted the attention to natural substances, such as plant extracts. The aim of this study was to investigate the possibility of using the essential oils (EOs) in the fight against S...
October 17, 2016: International Journal of Food Microbiology
Katsuhiko Hirota, Hiromichi Yumoto, Bayarmagnai Sapaar, Takashi Matsuo, Tetsuo Ichikawa, Yoichiro Miyake
Candida albicans is commonly found as a member of the human microflora and a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various microorganisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm-related infectious diseases...
October 21, 2016: Journal of Applied Microbiology
N Rostami, R C Shields, S A Yassin, A R Hawkins, L Bowen, T L Luo, A H Rickard, R Holliday, P M Preshaw, N S Jakubovics
Extracellular DNA (eDNA) has been identified in the matrix of many different monospecies biofilms in vitro, including some of those produced by oral bacteria. In many cases, eDNA stabilizes the structure of monospecies biofilms. Here, the authors aimed to determine whether eDNA is an important component of natural, mixed-species oral biofilms, such as plaque on natural teeth or dental implants. To visualize eDNA in oral biofilms, approaches for fluorescently stained eDNA with either anti-DNA antibodies or an ultrasensitive cell-impermeant dye, YOYO-1, were first developed using Enterococcus faecalis, an organism that has previously been shown to produce extensive eDNA structures within biofilms...
October 21, 2016: Journal of Dental Research
Leili Beytollahi, Maryam Pourhajibagher, Nasim Chiniforush, Roghayeh Ghorbanzadeh, Reza Raoofian, Babak Pourakbari, Bahador Abbas
BACKGROUND: The alternative antibacterial treatments of photodynamic therapy (PDT) and photothermal therapy (PTT) significantly affect microbiota inactivation. The aim of the present research was the assessment of the antimicrobial and anti-biofilm effects of PDT with toluidine blue O (TBO) and PTT with indocyanine green (ICG) on Streptococcus mutans as a cariogenic bacterium. MATERIALS AND METHODS: The S. mutans ATCC 35668 strain was treated with final concentrations of 0...
October 18, 2016: Photodiagnosis and Photodynamic Therapy
Lars Bjørndal, Catharina Amaloo, Merete Markvart, Vibe Rud, Klaus Qvortrup, Camilla Stavnsbjerg, Thomas Bjarnsholt
INTRODUCTION: The aim was to present a case report of a full-length extrusion of an obturator's core carrier into the maxillary sinus, causing clinical symptoms from the nose region with differential diagnostics aspects, which, in turn, led to several surgical treatments of the nostrils before diagnosis and correct endodontic retreatment of a maxillary right first molar. A 36-year-old man presented in 2012 with complaints from the right nostril region. Medical treatment with antibiotics and surgical procedures because of nasal stenosis resulted only in partial improvement...
October 18, 2016: Journal of Endodontics
A Reum Kim, Ki Bum Ahn, Hyun Young Kim, Ho Seong Seo, Cheol-Heui Yun, Seung Hyun Han
INTRODUCTION: Streptococcus gordonii is a predominant member of the oral microflora and has been isolated from root canals of teeth with refractory apical periodontitis. Biofilm formation is important for various dental diseases, and S. gordonii is involved in dental biofilm formation as an early colonizer. Although serine-rich repeat (SRR) adhesins of S. gordonii such as gordonii surface protein B (GspB) are associated with bacterial colonization, the role of GspB in biofilm formation is not clearly understood...
October 18, 2016: Journal of Endodontics
Xiaoxue Tong, Tania Triscari Barberi, Catherine H Botting, Sunil V Sharma, Mark J H Simmons, Tim W Overton, Rebecca J M Goss
BACKGROUND: Engineering of single-species biofilms for enzymatic generation of fine chemicals is attractive. We have recently demonstrated the utility of an engineered Escherichia coli biofilm as a platform for synthesis of 5-halotryptophan. E. coli PHL644, expressing a recombinant tryptophan synthase, was employed to generate a biofilm. Its rapid deposition, and instigation of biofilm formation, was enforced by employing a spin-down method. The biofilm presents a large three-dimensional surface area, excellent for biocatalysis...
October 21, 2016: Microbial Cell Factories
Siyao Wang, Yuewu Pu, Cheng Wei
The aim of this study was to characterize the pollutant removal efficiency and the microbial communities that arose in a newly designed waterfall biofilm reactor (WFBR) at different chemical oxygen demand/total nitrogen (COD/TN) ratios. The reactor was operated continuously for 28 days at different COD/TN ratios, and its efficiency was evaluated. Results showed that as the thickness of the biofilm increased, the structure of the biofilm encouraged anaerobic-aerobic, anoxic-anaerobic, and fully anaerobic conditions in one reactor...
October 21, 2016: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Rui Seixas, Tânia Raquel Santos, Jorge Machado, Luís Tavares, Fernando Bernardo, Teresa Semedo-Lemsaddek, Manuela Oliveira
The increase in prevalence of Salmonella 1,4,[5],12:i:- related infections over the last few years has been considered a public health issue in many European countries, especially as this serovar may be associated with tetraresistance to ampicillin, streptomycin, sulfonamides, and tetracyclines (R-type ASSuT). Salmonella 1,4,[5],12:i:- isolates (n = 187) obtained by the Portuguese National Laboratory from different sources, including human clinical cases (n = 170), veterinary (n = 10), environmental (n = 6), and food samples (n = 1), were collected from 15 districts between 2006 and 2011...
October 21, 2016: Foodborne Pathogens and Disease
Tabitha Bucher, Elena Kartvelishvily, Ilana Kolodkin-Gal
This work assesses different methodologies to study the impact of small molecule biofilm inhibitors, such as D-amino acids, on the development and resilience of Bacillus subtilis biofilms. First, methods are presented that select for small molecule inhibitors with biofilm-specific targets in order to separate the effect of the small molecule inhibitors on planktonic growth from their effect on biofilm formation. Next, we focus on how inoculation conditions affect the sensitivity of multicellular, floating B...
October 9, 2016: Journal of Visualized Experiments: JoVE
Ivana Nedeljkovic, Kumiko Yoshihara, Jan De Munck, Wim Teughels, Bart Van Meerbeek, Kirsten L Van Landuyt
BACKGROUND: In spite of contradicting results, the high susceptibility of composites for secondary caries is still often associated with the bacterial growth-stimulating effect of released methacrylate monomers. However, most studies that showed this effect were performed with techniques having inherent limitations (spectrophotometry). OBJECTIVES: Therefore, our objective was to determine the effect of four methacrylate monomers (2-Hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA), ethylene glycol dimethacrylate (EGDMA), diethylene glycol dimethacrylate (DEGDMA)) on the growth of two caries-associated bacteria, Streptococcus mutans and sobrinus, and one non-cariogenic species, Streptococcus sanguinis, using TaqMan quantitative polymerase chain reaction (qPCR) to quantify bacterial DNA...
October 20, 2016: Clinical Oral Investigations
Karolina Niska, Narcyz Knap, Anna Kędzia, Maciej Jaskiewicz, Wojciech Kamysz, Iwona Inkielewicz-Stepniak
Objectives: In dentistry, silver nanoparticles (AgNPs) have drawn particular attention because of their wide antimicrobial activity spectrum. However, controversial information on AgNPs toxicity limited their use in oral infections. Therefore, the aim of the present study was to evaluate the antibacterial activities against a panel of oral pathogenic bacteria and bacterial biofilms together with potential cytotoxic effects on human gingival fibroblasts of 10 nm AgNPs: non-functionalized - uncapped (AgNPs-UC) as well as surface-functionalized with capping agent: lipoic acid (AgNPs-LA), polyethylene glycol (AgNPs-PEG) or tannic acid (AgNPs-TA) using silver nitrate (AgNO3) as control...
2016: International Journal of Medical Sciences
Ranjith Rajendran, Ali May, Leighann Sherry, Ryan Kean, Craig Williams, Brian L Jones, Karl V Burgess, Jaap Heringa, Sanne Abeln, Bernd W Brandt, Carol A Munro, Gordon Ramage
Candida albicans biofilm formation is an important virulence factor in the pathogenesis of disease, a characteristic which has been shown to be heterogeneous in clinical isolates. Using an unbiased computational approach we investigated the central metabolic pathways driving biofilm heterogeneity. Transcripts from high (HBF) and low (LBF) biofilm forming isolates were analysed by RNA sequencing, with 6312 genes identified to be expressed in these two phenotypes. With a dedicated computational approach we identified and validated a significantly differentially expressed subnetwork of genes associated with these biofilm phenotypes...
October 21, 2016: Scientific Reports
A Tofiño-Rivera, M Ortega-Cuadros, D Galvis-Pareja, H Jiménez-Rios, L J Merini, M C Martínez-Pabón
BACKGROUND: Caries is a public health problem, given that it prevails in 60 to 90% of the school-age global population. Multiple factors interact in its etiology, among them dental plaque is necessary to have lactic acid producing microorganisms like Streptococcus from he Mutans group. Existing prevention and treatment measures are not totally effective and generate adverse effects, which is why it is necessary to search for complementary strategies for their management. AIM: The study sought to evaluate the eradication capacity of Streptococcus mutans biofilms and the toxicity on eukaryotic cells of Lippia alba and Cymbopogon citratus essential oils METHODOLOGY: Essential oils were extracted from plant material through steam distillation and then its chemical composition was determined...
October 17, 2016: Journal of Ethnopharmacology
Juliana Marioni, María Angel da Silva, José Luis Cabrera, Susana C Núñez Montoya, María Gabriela Paraje
BACKGROUND: Candida tropicalis is increasingly becoming among the most commonly isolated pathogens causing fungal infections with an important biofilm-forming capacity. PURPOSE: This study addresses the antifungal effect of rubiadin (AQ1) and rubiadin 1-methyl ether (AQ2), two photosensitizing anthraquinones (AQs) isolated from Heterophyllaea pustulata, against C. tropicalis biofilms, by studying the cellular stress and antioxidant response in two experimental conditions: darkness and irradiation...
November 15, 2016: Phytomedicine: International Journal of Phytotherapy and Phytopharmacology
Ahmed Abdel Megeed, M Ali Hayssam, Mohamed Z M Salem, Mohamed S El-Shikh, Ibrahim Ahmed Talea, Yahya A Alogaibi
Multidrug-resistant (MDR) Acinetobacter baumannii infections are a great public health concern and demand continuous surveillance and antibiotic stewardship. Virulence traits and the pathogenicity of Acinetobacter are less studied compared with the molecular epidemiological and antibiotic resistance profile of this organism. In our present study, we investigated the primary characteristics contributing to the virulence of MDR A. baumannii isolates and compared them with avirulent isolates. A total of 32 well-characterized MDR A...
October 19, 2016: Journal of AOAC International
Aksone Nouvong, Aaron M Ambrus, Ellen R Zhang, Lucas Hultman, Hilary Ann Coller
Chronic wounds are a common and debilitating complication for the diabetic population. It is challenging to study the development of chronic wounds in hu-man patients; by the time it is clear that a wound is chronic, the early phases of wound healing have passed and can no longer be studied. Because of this limita-tion, mouse models have been employed to better understand the early phases of chronic wound formation. In the past few years, a series of reports have high-lighted the importance of reactive oxygen species and bacterial biofilms in the development of chronic wounds in diabetics...
October 7, 2016: Physiological Genomics
Wei Qiu, Biao Ren, Huanqin Dai, Lixin Zhang, Qiong Zhang, Xuedong Zhou, Yuqing Li
OBJECTIVE: The aim of this study was to determine the inhibitory effect of eight antifungal drugs on S. mutans growth, biofilm formation and virulence factors. METHODS: The actions of antifungal drugs on S. mutans were determined by recovery plates and survival kinetic curves. Biofilms were observed by scanning electron microscopy and the viable cells were recovered on BHI plates, meanwhile biofilms were stained by BacLight live/dead kit to investigate the biofilm viability...
October 13, 2016: Archives of Oral Biology
Julia I Tandberg, Leidy X Lagos, Petter Langlete, Eva Berger, Anne-Lise Rishovd, Norbert Roos, Deepa Varkey, Ian T Paulsen, Hanne C Winther-Larsen
Membrane vesicles (MVs) are spherical particles naturally released from the membrane of Gram-negative bacteria. Bacterial MV production is associated with a range of phenotypes including biofilm formation, horizontal gene transfer, toxin delivery, modulation of host immune responses and virulence. This study reports comparative profiling of MVs from bacterial strains isolated from three widely disperse geographical areas. Mass spectrometry identified 119, 159 and 142 proteins in MVs from three different strains of Piscirickettsia salmonis isolated from salmonids in Chile (LF-89), Norway (NVI 5692) and Canada (NVI 5892), respectively...
2016: PloS One
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"