Molecular Epidemiology of Methicillin-Resistant Staphyloccocus aureus at a Low-Incidence Hospital over a 4-Year Period

Abstract Objective: To study the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) over a prolonged period of time with the aid of a molecular typing method (ribotyping). Setting: A 1,000-bed tertiary university medical center. Patients and Methods: Defined epidemiological data were recorded for all patients culture-positive for MRSA between 1989 and 1992. Ribotyping of MRSA strains was performed using three restriction enzymes: EcoRv, HindHI, and KpnI. Results: From 1989 to 1992, MRSA was isolated from clinical specimens in 98 patients and from surveillance cultures in 27 patients. Among the 122 isolates available for typing, 26 different ribotypes were identified. In 20% of the cases, MRSA was community-acquired, and a third of these patients never had been hospitalized previously. Nine ribotypes were responsible for more than one case (2 to 64 patients); 17 appeared only once. Epidemiological data correlated with ribotyping results revealed 14 epidemiologic clusters involving six different ribotypes, whereas only three outbreaks were suspected initially. The median follow-up after the last isolation of a given ribotype was 14 months (range, 1 to 42) for clusters and 25 months (range, 1 to 46) for ribotypes that appeared only once. During clusters, only 16% of the cases occurred after the implementation of control measures in the ward (breakthrough cases). Conclusions: The high diversity of MRSA strains observed over 4 years suggested that new strains were introduced continuously in our hospital. Furthermore, that 17 ribotypes were isolated only once, that breakthrough cases represented only 16% of the cases in clusters, and that the follow-up duration after the last isolation of a given ribotype was more than 14 months suggest that infection control measures were effective in limiting the nosocomial spread of MRSA over a prolonged period of tim

Diffusion Of Indigo Molecules Inside The Palygorskite Clay Channels

The search for durable dyes led several past civilizations to develop artificial pigments. Maya Blue (MB), manufactured in pre-Columbian Mesoamerica, is one of the best known examples of an organic-inorganic hybrid material. Its durability is due to the unique association of indigo molecule and palygorskite, a particular fibrous clay occurring in Yucatan. Despite 50 years of sustained interest, the microscopic structure of MB and its relation to the durability remain open questions. Combining new thermogravimetric and synchrotron X-ray diffraction analyses, we show that indigo molecules can diffuse into the channel of the palygorskite during the heating process, replacing zeolitic water and stabilizing the room temperature phases of the clay

Environmental impact for offshore wind farms: Geolocalized Life Cycle Assessment (LCA) approach

International audienceThis paper presents an approach for Environmental Impact Assessment through the use of geolocalized LCA approach, for fixed and floating offshore wind farms. This work was undertaken within the EU-sponsored EnerGEO project, aiming at providing a versatile modeling platform for stakeholders allowing calculation, forecasting and monitoring of environmental impacts of different sources of energy. This paper described the geolocalized LCA approach, and its use for the evaluation of environmental impacts of wind energy. The effects of offshore wind farms on global environnemental impacts are evaluated though the LCA approach. It takes into account the type of wind farm, the construction phase, all technical aspects, the operation and maintenance scheme and the decommissioning. It also includes geolocalized information such as wind resources, bathymetry, accessibility ... Environmental impact parameters are accessible through a web service helping the decision makers in assessing the environnemental impacts

Web tool for energy policy decision-making through geo-localized LCA models: A focus on offshore wind farms in Northern Europe

International audienceEnvironmental performances of electricity generation, expressed as environmental impacts per kWh of electricity produced, depend strongly on technical, methodological and geographical parameters. When considering the global environmental performances of renewable energies, a geo-dependent life cycle assessment (LCA) taking into account geographical issues is of high interest. To illustrate this issue, a web map service enabling "geolocalized life cycle assessment" of offshore wind farms for different configurations has been developed. Based on a modular LCA model and on collaborative works made within the framework of the FP7 co-funded project EnerGEO, the developed tool should help decision makers in assessing the global environmental impacts caused by an offshore wind farm in Northern Europe

Environmental data for the planning of off-shore wind parks from the EnerGEO Platform of Integrated Assessment (PIA)

International audienceThe EU-sponsored EnerGEO project aims at providing decision makers with a modelling platform to assess the environmental impacts of different sources of renewable energy. One of the pillars of the project is the Wind Energy Pilot, addressing the effects of offshore wind parks on air pollution and energy use. The methods used in the pilot and the underlying environmental databases are integrated into a WebGIS client tool and made available to the public. This paper is dedicated to describing the environmental databases and supporting data incorporated in the client tool. A 27-km resolution, 11-year wind database is created using the WRF model. The wind database is used to assess the wind climate in the north-west Atlantic region and to derive the potential power output from offshore wind parks. Auxiliary data concerning water depth, distance to shore and distance to the nearest suitable port are created to aid the planning and maintenance phases. Seasonal workability conditions are assessed using a 20-year wave database. The distance at which future wind parks should be placed to exhibit different wind climates is investigated

Pain perception after colorectal surgery: A propensity score matched prospective cohort study.

The purpose of this prospective cohort study was to compare multimodal pain management and pain perception after open vs. laparoscopic colorectal surgery within enhanced recovery care. Pain scores at rest and at mobilization were prospectively assessed in consecutive patients using Visual Analog Scales (VAS 0-10) and consumption of different analgesics was recorded daily until 96 hours postoperatively. Uni- and multivariate risk factors for pain peaks (≥ 4/10) were identified by logistic regression and compared between two propensity score matched groups (open vs. laparoscopic). 156 open and 176 laparoscopic procedures were included. Mean VAS scores were consistently < 3 until 96 hours at rest and at mobilization. Patients operated by laparoscopy experienced more pain peaks (≥ 4) within 24 hours (p < 0.05), while patients operated by open approach experienced more pain peaks (≥ 4) during mobilization at 72 hours (p < 0.05). Independent risk factors for insufficient pain control (≥ 4) within 24 hours from surgery were duration of the procedure (OR 3.37, 95%CI 2.03-5.59), emergency surgery (OR 3.01, 95%CI 1.72-5.31), wound infiltration (OR 3.23, 95%CI 0.97-10.70), age < 70 years (OR 2.03, 95% CI 1.18-3.48) and ASA I-II score (OR 2.06, 95% CI 1.19-3.56). The perioperative adding of lidocaine ± ketamine to opioids did not improve postoperative pain perception nor decrease morphine equivalents. In conclusion, overall pain scores were low after colorectal surgery. However, pain peaks remained a concern early after minimally invasive surgery and after epidural removal for open surgery. Multimodal strategies were not superior to opioids alone

Reductive Genome Evolution from the Mother of Rickettsia

The Rickettsia genus is a group of obligate intracellular α-proteobacteria representing a paradigm of reductive evolution. Here, we investigate the evolutionary processes that shaped the genomes of the genus. The reconstruction of ancestral genomes indicates that their last common ancestor contained more genes, but already possessed most traits associated with cellular parasitism. The differences in gene repertoires across modern Rickettsia are mainly the result of differential gene losses from the ancestor. We demonstrate using computer simulation that the propensity of loss was variable across genes during this process. We also analyzed the ratio of nonsynonymous to synonymous changes (Ka/Ks) calculated as an average over large sets of genes to assay the strength of selection acting on the genomes of Rickettsia, Anaplasmataceae, and free-living γ-proteobacteria. As a general trend, Ka/Ks were found to decrease with increasing divergence between genomes. The high Ka/Ks for closely related genomes are probably due to a lag in the removal of slightly deleterious nonsynonymous mutations by natural selection. Interestingly, we also observed a decrease of the rate of gene loss with increasing divergence, suggesting a similar lag in the removal of slightly deleterious pseudogene alleles. For larger divergence (Ks > 0.2), Ka/Ks converge toward similar values indicating that the levels of selection are roughly equivalent between intracellular α-proteobacteria and their free-living relatives. This contrasts with the view that obligate endocellular microorganisms tend to evolve faster as a consequence of reduced effectiveness of selection, and suggests a major role of enhanced background mutation rates on the fast protein divergence in the obligate intracellular α-proteobacteria