Chronic Suppurative Otitis Media: A Prospective Descriptive Study of the Microbiology and Antimicrobial Susceptibility Patterns.

Objective: This study aims to identify dominant causative pathogens of chronic suppurative otitis media (CSOM) and their antimicrobial susceptibility patterns. The secondary objective is to assess the cholesteatoma concurrence among this population.

Study Design: A prospective descriptive study.

E-cigarette use and respiratory symptoms in adults: A systematic review and meta-analysis.

Introduction: Electronic cigarette (e-cigarette) use is gaining popularity among adults. Monitoring e-cigarette-induced respiratory symptoms is crucial for both clinical and regulatory purposes. We systematically reviewed the current literature to understand the prevalence of respiratory symptoms among exclusive e-cigarette users, dual users, and former smokers.

Vibrational coherences in manganese single-molecule magnets after ultrafast photoexcitation.

Magnetic recording using femtosecond laser pulses has recently been achieved in some dielectric media, showing potential for ultrafast data storage applications. Single-molecule magnets (SMMs) are metal complexes with two degenerate magnetic ground states and are promising for increasing storage density, but remain unexplored using ultrafast techniques. Here we have explored the dynamics occurring after photoexcitation of a trinuclear µ-oxo-bridged Mn(III)-based SMM, whose magnetic anisotropy is closely related to the Jahn-Teller distortion.

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics.

Xenarthrans-anteaters, sloths, and armadillos-have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths.

Tetradecanuclearity in 3d-4f chemistry: relaxation and magnetocaloric effects in [NiLn] species.

The employment of 2-amino-isobutyric acid, Haib, and 2-hydroxy-1-naphthaldehyde, Hnaphth, in Ni/Ln chemistry has led to the isolation and characterization of two new isostructural 3d-4f tetradecanuclear [NiLn] clusters (Ln = Gd, Dy), with the Dy analogue displaying temperature and frequency dependent out-of-phase signals, and the Gd analogue showing interesting magnetocaloric properties.

Using certified timber extraction to benefit jaguar and ecosystem conservation.

The jaguar Panthera onca requires large areas of relatively intact habitats containing adequate amounts of prey to survive. Since a substantial portion of jaguar range occurs outside of strict protected areas, there is a need for economic incentives for habitat conservation, which carefully managed selective logging can provide. Forest Stewardship Council and Pan European Forest Council certifications intended to regulate wood extraction to maintain the ecological functions of forests require evidence of biodiversity and ecosystem conservation.

Averting biodiversity collapse in tropical forest protected areas.

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses.

Topographic distribution of bacteria associated with oral malodour on the tongue.

Objective: To investigate the topographic distribution of bacterial types and loads associated with mid-morning oral malodour on the tongue surface.

Design: Fifty subjects with good oral health and at least 20 natural uncrowned teeth were included. Samples were taken with sterile brushes from the dorsal anterior (DA), dorsal middle (DM), dorsal posterior (DP), dorsal posterior to the circumvallate papillae (DPCP), lateral posterior (LP) and ventral posterior (VP) tongue surfaces.

Removal of oral debris and bacteria during supervised tooth brushing.

Objective: To investigate foam generation during brushing, and the oral debris and bacteria removal efficacy of an experimental gel-to-foam dentifrice compared to a commercially-available dentifrice after brushing.

Methods: Thirty-four subjects participated in this blinded, crossover study. After a wash-out period prior to each session of product use, subjects reported to the site having abstained from oral hygiene, eating and drinking from 22:00 h on the evening prior to treatment visits.

Impact of different tongue cleaning methods on the bacterial load of the tongue dorsum.

Objective: To assess the extent and duration of the effect of tongue cleaning procedures on bacterial load on the dorsal surface of the tongue.

Methods: 19 subjects participated in this blinded crossover study. Subjects abstained from oral hygiene, eating and drinking from 22:00 h the previous evening.

Oral malodour--a review.

Halitosis is a very common condition which may affect up to 30% of the population. In most cases the aetiology of the condition is from local oral causes (oral malodour). Oral malodour is the result of the action of anaerobic bacteria in producing a range of malodorous molecular species including volatile sulphur compounds.

Control of brushing variables for the in vitro assessment of toothpaste abrasivity using a novel laboratory model.

Objectives: Design and construct a tooth-brushing simulator incorporating control of brushing variables including brushing force, speed and temperature, thereby facilitating greater understanding of their importance in toothpaste abrasion testing methodologies.

Methods: A thermostable orbital shaker was selected as a base unit and 16- and 24-specimen brushing rigs were constructed to fit inside, consisting of: a square bath partitioned horizontally to provide brushing channels, specimen holders for 25 mm diameter mounted specimens to fit the brushing channels and individually weighted brushing arms, able to support four toothbrush holders suspended over the brushing channels. Brush head holders consisted of individually weighted blocks of Delrin, or PTFE onto which toothbrush heads were fixed.

Determination of the genetic support for tet(W) in oral bacteria.

The DNA sequence flanking a tet(W) gene in an oral Rothia sp. was determined. The gene was linked to two different transposases, and these were flanked by two almost identical mef (macrolide efflux) genes.

Determining the antibiotic resistance potential of the indigenous oral microbiota of humans using a metagenomic approach.

Studies of the prevalence and identity of genes encoding resistance to antibiotics in a microbial community are usually carried out on only the cultivable members of the community. However, it is possible to include the as-yet-uncultivable organisms present by adopting a metagenomic approach to such studies. In this investigation, four metagenomic libraries of the oral microbiota were prepared from three groups of 20 adult humans and screened for antibiotic-resistant clones.

Genetic basis of erythromycin resistance in oral bacteria.

We determined the prevalence of erythromycin-resistant bacteria in the oral cavity and identified mef and erm(B) as the most common resistance determinants. In addition, we demonstrate the genetic linkage, on various Tn1545-like conjugative transposons, between erythromycin and tetracycline resistance in a number of isolates.

Biofilm-specific surface properties and protein expression in oral Streptococcus sanguis.

Objective: Oral streptococci are primary colonisers of the tooth surface and are abundant in dental plaque biofilms. Bacteria growing in these relatively dense, surface-associated communities are phenotypically quite distinct from their planktonic counterparts. The purpose of the present study was to develop a method to investigate biofilm-specific surface protein expression by Streptococcus sanguis to help provide a better understanding of the critical events in plaque development.

Microbial dinner-party conversations: the role of LuxS in interspecies communication.

Bacteria have a tendency to be gregarious by nature. Whether on abiotic surfaces in the environment or on the mucosal surfaces of humans, bacteria accumulate in complex multi-species communities. In these dynamic accretions, bacteria can be densely packed and often depend on each other for the provision of metabolic substrates.

Novel tetracycline resistance determinant from the oral metagenome.

A major drawback of most studies on how bacteria become resistant to antibiotics is that they concentrate mainly on bacteria that can be cultivated in the laboratory. In the present study, we cloned part of the oral metagenome and isolated a novel tetracycline resistance gene, tet(37), which inactivates tetracycline.

Prevalence of Csh-like fibrillar surface proteins among mitis group oral streptococci.

The prevalence of Csh-like fibrillar surface proteins among oral streptococci was investigated by ELISA and by immunoelectron microscopy using antiserum raised to recombinant fragments of CshA of Streptococcus gordonii DL1. The majority of S. gordonii, Streptococcus sanguis and Streptococcus oralis strains tested elaborated short (ca.

Prevalence of tetracycline resistance genes in oral bacteria.

Tetracycline is a broad-spectrum antibiotic used in humans, animals, and aquaculture; therefore, many bacteria from different ecosystems are exposed to this antibiotic. In order to determine the genetic basis for resistance to tetracycline in bacteria from the oral cavity, saliva and dental plaque samples were obtained from 20 healthy adults who had not taken antibiotics during the previous 3 months. The samples were screened for the presence of bacteria resistant to tetracycline, and the tetracycline resistance genes in these isolates were identified by multiplex PCR and DNA sequencing.

LuxS-based signaling in Streptococcus gordonii: autoinducer 2 controls carbohydrate metabolism and biofilm formation with Porphyromonas gingivalis.

Communication based on autoinducer 2 (AI-2) is widespread among gram-negative and gram-positive bacteria, and the AI-2 pathway can control the expression of genes involved in a variety of metabolic pathways and pathogenic mechanisms. In the present study, we identified luxS, a gene responsible for the synthesis of AI-2, in Streptococcus gordonii, a major component of the dental plaque biofilm. S.

Expression of fibronectin-binding protein FbpA modulates adhesion in Streptococcus gordonii.

Fibronectin binding is considered to be an important virulence factor in streptococcal infections. Adhesion of the oral bacterium Streptococcus gordonii to immobilized forms of fibronectin is mediated, in part, by a high molecular mass wall-anchored protein designated CshA. In this study, a second fibronectin-binding protein of S.

Streptococcus sanguis secretes CD14-binding proteins that stimulate cytokine synthesis: a clue to the pathogenesis of infective (bacterial) endocarditis?

Streptococcus sanguis is the major causative organism of infective (bacterial) endocarditis but, surprisingly, almost nothing is known about how it induces endocardial inflammation. In earlier studies we have shown that many bacteria secrete potent cytokine-inducing or -inhibiting proteins. We have therefore isolated the material secreted by S.