Efficacy of Infection Control Interventions in Reducing the Spread of Multidrug-Resistant Organisms in the Hospital Setting

Multidrug-resistant organisms (MDRO) continue to spread in hospitals globally, but the population-level impact of recommended preventive strategies and the relative benefit of individual strategies targeting all MDRO in the hospital setting are unclear. To explore the dynamics of MDRO transmission in the hospital, we develop a model extending data from clinical individual-level studies to quantify the impact of hand hygiene, contact precautions, reducing antimicrobial exposure and screening surveillance cultures in decreasing the prevalence of MDRO colonization and infection. The effect of an ongoing increase in the influx of patients colonized with MDRO into the hospital setting is also quantified. We find that most recommended strategies have substantial effect in decreasing the prevalence of MDRO over time. However, screening for asymptomatic MDRO colonization among patients who are not receiving antimicrobials is of minimal value in reducing the spread of MDRO

Image based machine learning for identification of macrophage subsets

Macrophages play a crucial rule in orchestrating immune responses against pathogens and foreign materials. Macrophages have remarkable plasticity in response to environmental cues and are able to acquire a spectrum of activation status, best exemplified by pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes at the two ends of the spectrum. Characterisation of M1 and M2 subsets is usually carried out by quantification of multiple cell surface markers, transcription factors and cytokine profiles. These approaches are time consuming, require large numbers of cells and are resource intensive. In this study, we used machine learning algorithms to develop a simple and fast imaging-based approach that enables automated identification of different macrophage functional phenotypes using their cell size and morphology. Fluorescent microscopy was used to assess cell morphology of different cell types which were stained for nucleus and actin distribution using DAPI and phalloidin respectively. By only analysing their morphology we were able to identify M1 and M2 phenotypes effectively and could distinguish them from naïve macrophages and monocytes with an average accuracy of 90%. Thus we suggest high-content and automated image analysis can be used for fast phenotyping of functionally diverse cell populations with reasonable accuracy and without the need for using multiple markers

Staphylococcal Enterotoxins

Staphylococcus aureus (S. aureus) is a Gram positive bacterium that is carried by about one third of the general population and is responsible for common and serious diseases. These diseases include food poisoning and toxic shock syndrome, which are caused by exotoxins produced by S. aureus. Of the more than 20 Staphylococcal enterotoxins, SEA and SEB are the best characterized and are also regarded as superantigens because of their ability to bind to class II MHC molecules on antigen presenting cells and stimulate large populations of T cells that share variable regions on the β chain of the T cell receptor. The result of this massive T cell activation is a cytokine bolus leading to an acute toxic shock. These proteins are highly resistant to denaturation, which allows them to remain intact in contaminated food and trigger disease outbreaks. A recognized problem is the emergence of multi-drug resistant strains of S. aureus and these are a concern in the clinical setting as they are a common cause of antibiotic-associated diarrhea in hospitalized patients. In this review, we provide an overview of the current understanding of these proteins

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Transcriptome-Based Network Analysis Reveals a Spectrum Model of Human Macrophage Activation

SummaryMacrophage activation is associated with profound transcriptional reprogramming. Although much progress has been made in the understanding of macrophage activation, polarization, and function, the transcriptional programs regulating these processes remain poorly characterized. We stimulated human macrophages with diverse activation signals, acquiring a data set of 299 macrophage transcriptomes. Analysis of this data set revealed a spectrum of macrophage activation states extending the current M1 versus M2-polarization model. Network analyses identified central transcriptional regulators associated with all macrophage activation complemented by regulators related to stimulus-specific programs. Applying these transcriptional programs to human alveolar macrophages from smokers and patients with chronic obstructive pulmonary disease (COPD) revealed an unexpected loss of inflammatory signatures in COPD patients. Finally, by integrating murine data from the ImmGen project we propose a refined, activation-independent core signature for human and murine macrophages. This resource serves as a framework for future research into regulation of macrophage activation in health and disease

Determination experimentale des principales caracteristiques physiques et mecaniques du bois du rônier (borassus aethiopum Mart.) d’origine beninoise

Le rônier (Borassus aethiopum Mart.) est un palmier dont le bois est assez utilisé pour sa résistance mécanique et sa tenue aux intempéries dans les constructions traditionnelles et même modernes en Afrique. Cependant, au Bénin et ailleurs, les connaissances sur les caractéristiques physiques et mécaniques de l’espèce restent empiriques et non maîtrisées. Dans le présent travail, les caractéristiques physiques et mécaniques usuelles du rônier originaire du sud-Bénin, sont déterminées. Il s’agit de la masse volumique basale, des taux de retraits totaux linéaire et volumique, du module d’Young dans la direction du fil du bois en flexion quatre points ainsi que la contrainte de rupture en traction simple, en compression simple, au cisaillement simple et enflexion quatre points. Borassus aethiopum is a palm tree of which the wood is used enough for its mechanical resistance as well as for its resistance to natural harsh conditions, in old construction of housing in Benin. But unfortunately, it is almost unknown as far as its scientific characteristics are concerned. Through the present research work, usual scientific parameters and characteristics of Borassus palm wood from Benin, are determined. Specifically, infradensity, shrinkage coefficient and behaviour, breaking stress in the direction of the fibbers at pulling, compression and bending, are known as well as Young modulus at bending. This knowledge will help for better use of Borassus palm wood in the construction of housing.xion quatre points.

Cartographie des directions dominantes des vents au Benin : Outil de conception et de dimensionnement des ouvrages

La présente étude a pour objet de déterminer les directions dominantes du vent et d'établir une carte région-vent du Bénin. Pour ce faire, nous avons, après la collecte des informations météorologiques, procédé : - à l’analyse des données (directions) des six stations météorologiques principales conformément aux méthodes statistiques. Ces données couvrent une période de 23 ans ; - au moyen des techniques numériques, à l’analyse des variations des directions ; - à l’analyse selon la norme AFNOR de l’influence du relief et de la végétation sur les directions. A l’issue de cette étude, nous avons établi des cartes régions appropriées. The present study aims to determine dominant directions of the wind and to establish a wind-region map of Benin. In order to do that, we have after the collection of meteorological information carried out: - the analysis of data (directions) of the six main meteorological stations in accordance with statistical methods. These data cover a period of 23 years; - the analysis of the variations of directions by means of numerical techniques; - the analysis of the influence of the relief and the vegetation on directions according to AFNOR norms. At the end of this study, we established appropriate regions maps

Analysis of pressure stabilizer elliptic chambers on the deformed state by numerical method

The question of pressure and flow rate stabilization is particularly relevant to short pipelines systems, which have high requirements for flow rate consistency of the working fluid. At medium and high pressures (up to 100 atmospheres and higher) the pressure stabilizer with elliptical elastic chambers provides conditions for normal operation of the corresponding equipment. For proper design of the stabilizer, especially deciding question of the liquid volume which the stabilizer can accommodate, it is necessary to carry out the calculation of the elliptical shell in the deformed state. The article provides the calculation of the elliptical shell in the deformed state by step by step loading method and checking the strength conditions at each step of loading. One of the main questions of the study is the question of what maximum load can withstand elliptical chambers. In this paper, we investigate the dependence of the maximum pressure at which the unit operates in the elastic area of deformation on the of the elliptical pipe wall thickness. If harmful oscillating discharge is known we should know the liquid volume which the camera can take. The dependence of the cross-sectional area increase coefficient on the thickness of the pipe wall is built. The article discusses some questions of pressure stabilizer designing

Vers des planches légers à partir d'entrevous en composites ciment-bois

No Abstract Available J. Rech. Sci. Univ. Lomé (Togo) 2002, 6(2) : 121-12