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Seasonal deformation of mountain rock slopes can be driven by groundwater infiltration and depletion. Such processes could explain our field observation in the Aletsch Valley, Switzerland, where GNSS‐derived 3D annual displacement amplitudes reach 3.4 cm. However, the physical mechanisms behind such groundwater‐driven surface displacements are not well understood. Here, we develop a fully coupled hydromechanical model to simulate the relevant processes in a valley slope embedded with numerous fractures of variable sizes. The magnitude and orientation of transient annual slope surface displacement obtained from our model are in overall agreement with the field observations. The key geological factors controlling the type and magnitude of reversible mountain slope deformations are fracture network geometry, fracture aperture, and regional stress field. We show that the heterogeneity and anisotropy of bedrock hydromechanical responses, originating from depth‐dependent variations of fracture properties, play a critical role in groundwater recharge and valley slope deformation. During recharge events, pore pressure perturbations migrate downward from the groundwater table and toward the receiving stream and the deep subsurface. This process driven by pressure diffusion and poroelastic stressing develops in the subsurface with a great reach of up to a few kilometers, called critical hydromechanical response zone, and controls surface deformation patterns. During groundwater recession, this hydromechanical response zone expands downward and ground surface displacement vectors rotate upwards. Our results suggest that slope surface deformation can inform about subsurface permeability structures and pore pressure fluctuations, which have important implications for understanding groundwater flow in fractured bedrock slopes. Plain Language Summary: Groundwater recharge in alpine valleys mainly occurs during snowmelt and/or rainstorm events. When recharge raises groundwater table in the slope, the bedrock can deform, and centimeter‐scale surface displacements can be observed. Here, we model this process in an alpine valley and investigate how bedrock fractures and regional stresses affect the surface displacement pattern. We show that slope surface deformation is controlled by a so‐called hydromechanical response zone reaching up to a few kilometers below the valley ridges. The shape and location of this zone change throughout the year. We compare our modeling results with long‐term deformation records from the lower Aletsch Valley, Switzerland, and show that they are in general agreement. The results of this work and insights obtained advance our fundamental understanding of the mechanisms of groundwater‐driven deformations in fractured rock slopes. Our research opens an avenue to use the information of surface deformation patterns to infer subsurface hydrogeological processes. Key Points: Coupled hydromechanical simulations are compared to surface displacement magnitude, orientation and hysteresis observed at Aletsch, SwitzerlandGroundwater recharge‐related pressure diffusion and poroelastic stressing in subsurface rock drive slope surface displacementCentimeter‐scale slope surface displacements occur in fractured crystalline rock with permeability in the narrow range of 10−16–10−14 m2 [ABSTRACT FROM AUTHOR]

Introduction: Osteoarthritis is a chronic pathology that involves multidisciplinary management. Self-management for patients is an essential element, present in all international guidelines. During the time of the spa therapy, the patient is receptive to take the advantage of self-management workshops. The aim of this study is to assess the effects of 18 days spa therapy associated with a self-management intervention in patients with knee osteoarthritis in comparison with spa therapy alone on a priority objective, personalized and determined with the patient, chosen in the list of 5 objectives determined during the self-management initial assessment. Methods and analysis: Two hundred fifty participants with knee osteoarthritis will participate to this multicenter, prospective, randomized, controlled study. All patients will benefit 18 days of spa therapy and patients randomized in the intervention group will participate to 6 self-management workshops. Randomization will be centralized. The allocation ratio will be 1:1. Data analysts and assessor will be blinded. The primary outcome is the effectiveness of the educational workshops associated with spa therapy in comparison with spa therapy alone on a priority objective, measured by Goal Attainment Scaling (GAS). The secondary outcomes are disability, health-related quality of life, and pain intensity. Ethics and dissemination: Ethics were approved by the CPP Sud-Méditerranée II. The results will be disseminated in a peer-reviewed journal and disseminated at PRM, rheumatology, and orthopedics conferences. The results will also be disseminated to patients. Trial registration: Trial registration number NCT03550547. Registered 8 June 2018. Date and version identifier of the protocol. Version N°6 of March 12, 2018. [ABSTRACT FROM AUTHOR]

A comprehensive surface displacement monitoring system installed in the recently deglaciated bedrock slopes of the Aletsch Valley shows systematic reversible motions at the annual scale. We explore potential drivers for this deformation signal and demonstrate that the main driver is pore pressure changes of groundwater in fractured granitic mountain slopes. The spatial pattern of these reversible annual deformations shows similar magnitudes and orientations for adjacent monitoring points, leading to the hypothesis that the annually reversible deformation is caused by slope‐scale groundwater elevation changes and rock mass properties. Conversely, we show that the ground reaction to infiltration from snowmelt and summer rainstorms can be highly heterogeneous at local scale, and that brittle‐ductile fault zones are key features for the groundwater pressure‐related rock mass deformations. We also observe irreversible long‐term trends (over the 6.5 years data set) of deformation in the Aletsch valley composed of a larger uplift than observed at our reference GNSS station in the Rhone valley, and horizontal displacements of the slopes towards the valley. These observations can be attributed respectively to the elastic bedrock rebound in response to current glacier mass downwasting of the Great Aletsch Glacier and gravitational slope deformations enabled by cyclic groundwater pressure‐related rock mass fatigue in the fractured rock slopes. Plain Language Summary: Mountain ranges are subject to deformation due to tectonic forces, orogenesis, erosion, and gravity. Other factors can deform the slopes, such as atmospheric‐driven thermal expansion and contraction, freeze‐thaw in open fractures, and pore pressure variations. Close to retreating glaciers, the mechanical unloading of the ice body, and rapidly changing thermal and hydrologic conditions lead to deformation of the slopes. The difficulty resides in identifying the different factors contributing to the total deformation. We track surface displacements of fractured crystalline rock slopes adjacent to the Great Aletsch Glacier (Switzerland) tongue for more than six years at unprecedentedly high spatial and temporal resolutions. Our results demonstrate that groundwater is a critical driver of deformation. Centimetric reversible outward displacements are observed after the snowmelt season each year, followed by a seasonal recession to which are superimposed displacements caused by heavy rainfall‐recharge events. Fault zones can be key features where most of the hydromechanical deformation occurs, and their geometry can control the direction of deformation. Glacier melting induces long‐term trends of deformation. In addition, annual pore‐pressure cycles lead to hydromechanical fatigue processes. This work opens a new vision on the spatial and temporal variability of processes responsible for bedrock deformation in paraglacial mountain slopes. Key Points: Seasonal pore pressure variations in fractured crystalline hillslope induce correlated reversible surface deformationsDecameter‐scale brittle‐ductile faults control local spatial variations of deformation patternsCyclic groundwater pressure‐related rock mass fatigue induces irreversible gravitationally driven displacements in valley slopes [ABSTRACT FROM AUTHOR]

Recession analysis is widely used for characterizing aquifer and basin properties based on the falling limb of the hydrograph. However, recession analysis using streamflow discharge requires a relationship (the rating curve) between simultaneous measurements of water height, h, and discharge, Q, across a wide range of flows, which is expensive to obtain, and changes in time. We leverage the relationship between h and Q (typical power law) to perform recession analysis using h directly, thus permitting identification of transient flow regimes, where only h is available. Recession analysis evaluates the rate of change in discharge, −dQ/dt, as a function of discharge, Q, in a bilogarithmic plot where the slope, b, contains information about aquifer characteristics. While values of b are not conserved when replacing Q with h, we find that the variability in values of b within and between events is captured in recession analysis for both Q and h. For example, when considering individual recessions from a large number of watersheds, a change from a smaller b at high discharge/stage to a larger b at lower discharge/stage occurs in most watersheds and suggests a transition to a more long‐lasting, and less drought‐sensitive, baseflow regime. With the advent of low‐cost reliable pressure loggers, as well as satellites that provide global reporting of river stage, recession analysis using water height expands the number of river systems where recession analysis can be conducted and provides the potential for insights into the variability of watershed drainage characteristics without the need for a discharge record. Key Points: Using water height in place of discharge for recession analysis preserves general characteristics of the recession curveAn analytical expression equating the power law exponents of water height and discharge is given when the rating curve is a power lawThe ratio of power law exponents for individual recessions at high and low water heights can identify a transition in streamflow regimes [ABSTRACT FROM AUTHOR]

Cross‐hole fluid injection tests were performed on shallow (0.5 km depth) crustal fault zones to characterize their internal flow structures on scales of 3–30 m. The data were acquired at the Grimsel Rock Laboratory, Switzerland, after the zonal isolation of damage zones in boreholes equipped with multipacker systems. We show that 80% of the pressure responses detected evolved as a power function of time due to fracture‐controlled flow and were best described by a fractional model with a flow dimension (n) in the range of [1.3,1.5]. The scaling of characteristic times (tc) and intermediate transitions in the flow dimension is shown to be inconsistent with the trend expected for normal diffusion, indicating a diffusion slowdown process caused by the spatial integration of structurally different damage zones. An analysis of the entire data set points to a subdiffusive regime where the mean squared displacement of pressure fronts, ⟨r2(t)⟩, scales as ⟨r2(t)⟩∝t0.59, similar to an anomalous diffusion process on synthetic fractal systems. We characterize this diffusion slowdown by calculating a network connectivity exponent (θ) of 1.4, from which we estimate a fractal dimension of df=2.23 for the tested fault zones. Such a value close to 2.0 supports the view of fault damage zones as hierarchical systems promoting flow channeling. Our results provide further support to theoretical models of fractional flow and their application to fractured media in nature. Key Points: We report direct, high‐resolution observations of pressure diffusion from fluid injection tests in shallow crustal fault zonesFractional flow regimes systematically emerge in response to spatial integration of structurally different damage zones during injectionThe fractal structure of damage zones may explain the emergence of anomalously slow pressure diffusion around faults [ABSTRACT FROM AUTHOR]

New in situ measurements to constrain the range, distribution, and spatial (meter‐scale) variations of permeability in shallow crustal fault zones are reported based on systematic downhole tests at 0.5‐km depth in crystalline rock. Single and cross‐hole hydraulic packer tests were performed at a new dedicated test facility hosted in the Grimsel Test Site, in the Swiss Alps, following the technical instrumentation and isolation of discrete fault zones accessed by an array of boreholes. Single‐hole test results are presented in this paper, while cross‐hole experiments are reported in the companion paper. Our results reveal a sharp spatial falloff in permeability, from 10‐13 to 10‐21 m2, with off‐fault distances of 1–5 m and characterized by a power‐law relation with fracture density. Fractures linking subparallel faults were detected as high‐permeability discrete spots several meters away from off‐fault damage. Due to the narrow (centimeter‐wide) thickness of fault cores, the hydraulic tests presented in this study do not characterize the permeability of fault core materials. The transmissivity of single fractures spans six orders of magnitude (10‐12 to 10‐6 m2/s) and is systematically higher in damage zones. In situ stresses appear to have a minor effect on natural, present‐day fracture transmissivity at the borehole scale. We suggest that the geometrical and topological properties of fracture systems instead tend to control the permeability of the shallow crustal faults studied. Key Points: We mapped permeability variations across shallow crustal fault zones through systematic downhole pressure pulse testsA sharp permeability decay up to eight orders of magnitude with off‐fault distance is observedGeometry and topology exert a dominant control on the permeability of fracture systems in shallow crustal settings [ABSTRACT FROM AUTHOR]

Abstract: Aims: To investigate the potent control of microbial surface contamination of an innovative process which consists in incorporating metal oxide microspheres homogeneously into materials. Methods and Results: Spherical microspheres containing zinc and magnesium oxides synthesized via a one‐step manufacturing process (Pyrolyse Pulvérisée®) and incorporated into different plastic matrices were evaluated for their antimicrobial activity according to JIS Z 2801 standard. A significant activity was observed for microsphere‐added polyethylene coupons with a reduction of all tested bacteria populations, including Gram negative and Gram positive even expressing acquired antibiotic resistance (Escherichia coli ESBL, Staphylococcus aureus metiR). An antiviral activity higher than 2 log of reduction was also observed on H1N1 and HSV‐1 viruses. This antimicrobial effect was dose‐dependent and time‐dependent for both polyethylene and polypropylene matrices. Antimicrobial activity was maintained after exposition to disinfectants and totally preserved 50 months after the preparation of the coupons. Conclusions: Incorporated into plastic matrices, metal oxide microspheres showed significant antibacterial and antiviral activities. Significance and Impact of Study: This is, to our knowledge, the first report on an original process incorporating metal oxide microspheres, which have specific physico‐chemical and antimicrobial properties, into materials that could be used for surface contamination prevention. [ABSTRACT FROM AUTHOR]

Abstract: While the commensal bacterium Propionibacterium acnes (P. acnes) is involved in the maintenance of a healthy skin, it can also act as an opportunistic pathogen in acne vulgaris. The latest findings on P. acnes shed light on the critical role of a tight equilibrium between members of its phylotypes and within the skin microbiota in the development of this skin disease. Indeed, contrary to what was previously thought, proliferation of P. acnes is not the trigger of acne as patients with acne do not harbour more P. acnes in follicles than normal individuals. Instead, the loss of the skin microbial diversity together with the activation of the innate immunity might lead to this chronic inflammatory condition. This review provides results of the most recent biochemical and genomic investigations that led to the new taxonomic classification of P. acnes renamed Cutibacterium acnes (C. acnes), and to the better characterisation of its phylogenetic cluster groups. Moreover, the latest data on the role of C. acnes and its different phylotypes in acne are presented, providing an overview of the factors that could participate in the virulence and in the antimicrobial resistance of acne‐associated strains. Overall, this emerging key information offers new perspectives in the treatment of acne, with future innovative strategies focusing on C. acnes biofilms and/or on its acne‐associated phylotypes. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Our main objective was to compare Cutibacterium acnes (C. acnes) skin colonisation in patients with mild to moderate acne versus healthy controls and secondly, to evaluate a Myrtacine®‐based cream on C. acnes total population and antibioresistant Cutibacteria in patients with acne. Methods: In 60 acne patients (Global Acne Severity Scale, GEA grades 2–3), of mean age 20 [15–30] years and in 24 age‐ and sex‐ matched healthy controls, forehead strips samplings were performed for microbiological analysis of comedones by colony forming unit (CFU) counts of global C. acnes and erythromycin (EryR) or clindamycin‐resistant (ClnR) populations of Cutibacterium and determination of phylotypes by MALTI‐TOF. Clinical evaluations of acne patients (GEA, lesion count, porphyrin fluorescence) were performed at baseline and after 56 days of twice‐daily application of a Myrtacine®‐based cream. Results: We first showed (i) high and similar levels of C. acnes colonisation in superficial pilosebaceous follicles and detection of EryR and ClnR strains in both acne and control groups; (ii) different repartition of phylotypes in acne patients versus healthy control, with a predominance of phylotype IA in acne patients and a link between phylotype IA and erythromycin resistance. Besides, after treatment with the Myrtacine®‐based cream in acne patients, there was no change in C. acnes total load, but a significant decrease of EryR Cutibacteria, reduced porphyrin production by C. acnes, a decrease in acne severity (GEA), associated with reduced retentional and inflammatory lesions. Conclusion: Cutibacterium acnes colonisation was not significantly different in acne versus control groups. Phylotype IA was predominant in acne patient and in EryR C. acnes. A Myrtacine®‐based cream significantly reduced the level of EryR Cutibacteria in vivo and improved acne lesions. [ABSTRACT FROM AUTHOR]

Rivers are known to be major contributors to eutrophication in marine coastal waters, but little is known on the short-term impact of freshwater surges on the structure and functioning of the marine plankton community. The effect of adding river water, reducing the salinity by 15 and 30%, on an autumn plankton community in a Mediterranean coastal lagoon (Thau Lagoon, France) was determined during a 6-day mesocosm experiment. Adding river water brought not only nutrients but also chlorophyceans that did not survive in the brackish mesocosm waters. The addition of water led to initial increases (days 1-2) in bacterial production as well as increases in the abundances of bacterioplankton and picoeukaryotes. After day 3, the increases were more significant for diatoms and dinoflagellates that were already present in the Thau Lagoon water (mainly Pseudo-nitzschia spp. group delicatissima and Prorocentrum triestinum) and other larger organisms (tintinnids, rotifers). At the same time, the abundances of bacterioplankton, cyanobacteria, and picoeukaryote fell, some nutrients (NH , SiO ) returned to pre-input levels, and the plankton structure moved from a trophic food web based on secondary production to the accumulation of primary producers in the mesocosms with added river water. Our results also show that, after freshwater inputs, there is rapid emergence of plankton species that are potentially harmful to living organisms. This suggests that flash flood events may lead to sanitary issues, other than pathogens, in exploited marine areas. [ABSTRACT FROM AUTHOR]

Copyright of Phytothérapie is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To investigate the effect of tizanidine (an alpha(2) noradrenergic agonist) on transmission in the interneuronal pathway coactivated by group I and group II afferents in post-stroke patients with spastic hemiplegia.Methods: Early and late facilitation of the quadriceps H reflex elicited in the common peroneal nerve--attributed to non-monosynaptic group I and group II excitation, respectively--was investigated in 14 spastic hemiplegic patients. All received a single dose of tizanidine (150 microg/kg) or placebo in randomised order at 10 day intervals. Repeated measurements were made at baseline (T0), 45-90 min, and 120 min after drug intake. Spasticity was assessed by modified Ashworth score in the quadriceps muscle and by a leg tone score calculated by the sum of the modified Ashworth score in five muscle groups.Results: On the spastic side a decrease in late group II and, to a lesser extent, early group I common peroneal nerve induced quadriceps H reflex facilitation occurred with tizanidine (group II, mean (SEM) difference T0-T90: 34.3 (10.2)%, p<0.001; group I, T0-T120: 19.8 (9)%, p<0.05), but not with placebo (group II, difference T0-T90: 12.5 (8)%, NS; group I, T0-T120: 3.2 (7)%, NS). Tizanidine but not placebo decreased the quadriceps muscle and global lower limb Ashworth scores (2.9 (0.2) to 1.9 (0.3), p<0.001; and 12 (0.7) to 9.5 (0.8), p<0.0001, respectively).Conclusions: Enhancement of group II-group I facilitation of the quadriceps motor neurones on the spastic side of hemiplegic patients is modulated by alpha(2) noradrenergic agonists. This strengthens the view that late facilitation of quadriceps motor neurones is mediated by group II afferents and suggests that group II pathways may be involved in lower limb spasticity. [ABSTRACT FROM AUTHOR]

Size fractionation was performed using water from the Great Reef of Toliara (Madagascar) taken from two different habitats (ocean and lagoon) during the dry and wet seasons, to study the growth and mortality rates of bacterioplankton. Experiments were conducted with 1 and 100% of heterotrophic nanoflagellate (HNF) concentrations and virus-free water was obtained by tangential filtration (10 kDa). During the dry season, in both environments, bacterial abundance and production were significantly lower than values recorded during the wet season. Bacterial growth rates without grazers were 0.88 day-1 in the lagoon and 0.58 day-1 in the ocean. However, growth rates were statistically higher without grazers and viruses (1.58 day-1 and 1.27 day-1). An estimate of virus-induced bacterial mortality revealed the important role played by viruses in the lagoon (0.70 day-1) and the ocean (0.69 day-1). During the wet season, bacterial growth rates without grazers were significantly higher in both environments than were values obtained in the dry season. However, the bacterial growth rates were paradoxally lower in the absence of viruses than with viruses in both environments. Our results suggest that changes in nutrient concentrations can play an important role in the balance between viral lysis and HNF grazing in the bacterial mortality. However, virus-mediated bacterial mortality is likely to act simultaneously with nanoflagellates pressure in their effects on bacterial communities. [ABSTRACT FROM AUTHOR]

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims To investigate the preventive effects of an original combination of a grape seed extract ( GSE) with an amine fluoride ( Fluorinol®) on dental plaque formation and oxidative damage caused by oral bacteria. Methods and Results The antibacterial activity of the compounds was assessed using the broth macrodilution method, and their antiplaque activity was evaluated on a multispecies biofilm grown on saliva-coated hydroxyapatite discs. The effect on glucosyltransferases activity was analysed through reductions in the overall reaction and the quantity of insoluble glucan synthesized. The combination of 2000 μg ml−1 of GSE with 10·2 mg ml−1 of Fluorinol® significantly decreased the biofilm formation (up to 4·76 log10 of reduction) and inhibited by 97·4% the insoluble glucan synthesis by glucosyltransferases. The antioxidant activity of this combination, alone or incorporated into a formulated mouthwash (Eludril daily®), was determined using the Trolox equivalent antioxidant capacity assay ( TEAC), and both showed significantly greater antioxidant capacity than vitamin C. Conclusions The GSE/ Fluorinol® combination showed both a significant antiplaque activity and an important antioxidant capacity in vitro, without any bactericidal effects. Significance and Impact of the Study This is, to our knowledge, the first report on the properties of an original combination of a polyphenolic extract with amine fluoride that could be used for the prevention of oral diseases and oxidative damage associated. [ABSTRACT FROM AUTHOR]

The way in which bacterial communities colonize flow in porous media is of importance, but basic knowledge on the dynamic of these phenomena is still missing. The aim of this work is to develop microfluidic experiments in order to progress in the understanding of bacteria capture in filters and membranes. PDMS microfluidic devices mimicking filtration processes have been developed to allow a direct dynamic observation of bacteria across 10 or 20 µm width microchannels. When filtered in such devices, bacteria behave surprisingly: Escherichia coli, Pseudomonas aeruginosa or Staphylococcus aureus accumulate in the downstream zone of the filter and form large streamers which oscillate in the flow. In this study, streamer formation is put in evidence for bacteria suspension in non nutritive conditions in less than 1 h. This result is totally different from the one observed in same system with "inert" particles or dead bacteria which are captured in the bottleneck zone and are accumulated in the upstream zone. Observations within different flow geometries (straight channels, connected channels, and staggered row pillars) show that the bacteria streamer development is influenced by the flow configuration and, particularly by the presence of tortuosity within the microchannels zone. These results are discussed at the light of 3D flow simulations. In confined systems and in laminar flow, there is secondary flow (z-velocities) superimposed to the streamwise motion (in xy plane). The presence of the secondary flow in the microsystems has an effect on the bacterial adhesion. A scenario in three steps is established to describe the formation of the streamers and to explain the positive effect of tortuous flow on the development kinetics. [ABSTRACT FROM AUTHOR]

Luminescent silica nanoparticles are frequently employed for biotechnology applications mainly because of their easy functionalization, photo-stability, and biocompatibility. Bifunctional silica nanoparticles (BSNPs) are described here as new efficient tools for investigating complex biological systems such as biofilms. Photoluminescence is brought about by the incorporation of a silylated ruthenium(II) complex. The surface properties of the silica particles were designed by reaction with amino-organosilanes, quaternary ammonium-organosilanes, carboxylate-organosilanes and hexamethyldisilazane. BSNPs were characterized extensively by DRIFT,13C and29Si solid state NMR, XPS, and photoluminescence. Zeta potential and contact angle measurements exhibited various surface properties (hydrophilic/hydrophobic balance and electric charge) according to the functional groups. Confocal laser scanning microscopy (CLSM) measurements showed that the spatial distribution of these nanoparticles inside a biofilm ofPseudomonas aeruginosaPAO1 depends more on their hydrophilic/hydrophobic characteristics than on their size. CLSM observations using two nanosized particles (25 and 68 nm) suggest that narrow diffusion paths exist through the extracellular polymeric substances matrix. [ABSTRACT FROM AUTHOR]

Currently, models for studying Legionella pneumophila biofilm formation rely on multi-species biofilms with low reproducibility or on growth in rich medium, where planktonic growth is unavoidable. The present study describes a new medium adapted to the growth of L. pneumophila monospecies biofilms in vitro. A microplate model was used to test several media. After incubation for 6 days in a specific biofilm broth not supporting planktonic growth, biofilms consisted of 5.36 ± 0.40 log (cfu cm-2) or 5.34 ± 0.33 log (gu cm-2). The adhered population remained stable for up to 3 weeks after initial inoculation. In situ confocal microscope observations revealed a typical biofilm structure, comprising cell clusters ranging up to ∼300 μm in height. This model is adapted to growing monospecies L. pneumophila biofilms that are structurally different from biofilms formed in a rich medium. High reproducibility and the absence of other microbial species make this model useful for studying genes involved in biofilm formation. [ABSTRACT FROM AUTHOR]

Objective To determine whether spa therapy, plus home exercises and usual medical treatment provides any benefit over exercises and usual treatment, in the management of knee osteoarthritis. Methods Large multicentre randomised prospective clinical trial of patients with knee osteoarthritis according to the American College of Rheumatology criteria, attending French spa resorts as outpatients between June 2006 and April 2007. Zelen randomisation was used so patients were ignorant of the other group and spa personnel were not told which patients were participating. The main endpoint criteria were patient self-assessed. All patients continued usual treatments and performed daily standardised home exercises. The spa therapy group also received 18 days of spa therapy (massages, showers, mud and pool sessions). Main Endpoint The number of patients achieving minimal clinically important improvement (MCII) at 6 months, defined as ≥19.9 mm on the visual analogue pain scale and/or ≥9.1 points in a normalised Western Ontario and McMaster Universities osteoarthritis index function score and no knee surgery. Results The intention to treat analysis included 187 controls and 195 spa therapy patients. At 6 months, 99/195 (50.8%) spa group patients had MCII and 68/187 (36.4%) controls (χ=8.05; df=1; p=0.005). However, no improvement in quality of life (Short Form 36) or patient acceptable symptom state was observed at 6 months. Conclusion For patients with knee osteoarthritis a 3-week course of spa therapy together with home exercises and usual pharmacological treatments offers benefit after 6 months compared with exercises and usual treatment alone, and is well tolerated. NCT00348777. [ABSTRACT FROM PUBLISHER]

According to the latest forecasts of the INSEE (1) - Institut National de la Statistique et des Etudes Economiques (National Statistics and Economic Studies Institute), ageing of the French population will increase between 2005 and 2050: whereas 20.8% of the population living in continental France reached the age of 60 years or more in 2005, this proportion would be of 30.6% in 2035 and 31.9% in 2050. In 2050, 22.3 million persons will have reached the age of 60 years or more compared to 12.6 million in 2005, increasing by 80; in a 45-year period. In line with the actual age pyramid, ageing is unavoidable, as those who will reach 60 years of age in 2050 are already born (in 1989 or before). This expansion will be most important between 2006 and 2035, when the numerous "baby-boom" generations born between 1946 and 1975, will reach these ages. In future years, lifespan improvement will only emphasize this increase. Even if life expectancy stabilizes at the 2005 level, the number of seniors reaching 60 years or more would still increase to 50% between 2005 and 2050. This issue is identical in all countries of the European Union. Ageing is a major risk factor for dementia that will considerably worsen in the next years, if no curative therapies are found. Today, 25 million persons in the world suffer from Alzheimer's disease (AD). In France, it is estimated that 860 000 persons are affected and that 225 000 news cases are annually diagnosed. After 75 years of age, more than 20% of women and 13% of men are concerned. Forecasts for the coming years are frightening. Considering ageing of the population, the number of Alzheimer's disease cases should raise to 1.3 million in 2020 (20 patients for 1000 inhabitants) ant 2.1 million in 2040 (30 patients for 1000 inhabitants) (2). [ABSTRACT FROM AUTHOR]

The structure of the secretory tissues and the essential oil of the leaves of Croton campestris St Hil. were studied. The oil isolated by hydrodistillation was analyzed by CC and CC/MS and was found to contain 75 components accounting for 92.9% of the total oil, with the major components being caiyophyllene oxide (29.9%) and humulene oxide 11(8.0%). Growth inhibitory activity of the active compounds in solution was evaluated by measuring Minimal Inhibitory Concentration using a broth micro-method. The Minimal Inhibitory Concentration of the leaf oil was 1.56 μg/mL for Staphylococcus aureus, 6.25 μg/mL for Enterrococcus hirae and 6.25 μg/mL for Candida albicans. [ABSTRACT FROM AUTHOR]

Copyright of Pelvi-Perineologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Postoperative endophthalmitis following intraocular lens (IOL) implantation is still one of the most feared complications of cataract surgery. Bacterial adhesion to IOLs during their insertion is a prominent etiological factor. Polypropylene was the first biomaterial that allowed this relation of cause and effect to be proven. Following adhesion, bacteria replicate, congregate and form multiple layers of microcolonies which actually represent the basic structural unit of the biofilm. The bacteria are embedded in a slime layer. Personal photographs illustrate the different steps of biofilm formation. This slime matrix is not only an adhesive medium; it also affects virulence. Adhesion to IOLs has been studied by several in vitro studies and discrepancies can be found between them which are due to variations of experimental conditions. The strains, the incubation times and the methods all varied. Adhesion is affected by the nature of the IOLs, the isolates and the surrounding medium. Since this medium is very difficult to model because of its complexity, in vivo studies seemed essential. We have recently determined in vivo evolution of the amount of attached bacteria to five types of IOLs. Crystalline lenses from 90 domestic pigs were removed aseptically and replaced with previously infected IOLs. There have been few epidemiological studies published to determine the relationship between endophthalmitis and the IOL type. However, the perfect biomaterial that could prevent postoperative endophthalmitis does not yet exist. Globally, hydrophilic materials and hydrophobic acrylic seem to be less sticky than silicone or PMMA, but this remains to be proven clinically. [ABSTRACT FROM AUTHOR]

Persons with dementia when transferred between care settings are at risk for their condition to deteriorate. Maintaining continuity across the continuum of care is essential for the well being of these individuals. To enhance the continuity of care for Copper Ridge residents hospitalized for psychiatric symptoms, Copper Ridge and Johns Hopkins Hospital developed a Tele-medicine program to link clinical teams at each facility. Positive findings after one year included a reduction in the number of hospital stays, a reduction in the length of hospital stays, and improved care planning. The Tele-medicine program was under the leadership of the social work staff. [ABSTRACT FROM AUTHOR]

Objective: A potent heteronymous group II excitation of quadriceps motor neurons has been recently demonstrated in normal subjects. The present study was undertaken to investigate whether this heteronymous group II excitation also contributes to spasticity in hemiplegic patients.Method: The early and late facilitations of the quadriceps H reflex elicited by a conditioning volley to the common peroneal nerve at three times motor threshold, attributed to non-monosynaptic group I and group II excitations respectively, were investigated. The comparison was drawn between results obtained in 20 patients after stroke, with hemiplegia due to a vascular lesion in the territory of the middle cerebral artery, and 20 age and sex matched normal subjects.Results: A significant increase in the group I as well as in the group II common peroneal nerve induced facilitation of the quadriceps H reflex was seen on the spastic side of the patients (group I: 159 (SEM 10)% of control H reflex; group II: 165 (SEM 8)%) compared with their unaffected side (group I: 126 (SEM 4)%; group II: 128 (SEM 5)%) (Wilcoxon signed rank test, p<0. 01), or to the right (group I: 132 (SEM 4)%; group II: 131 (SEM 5)%) or left (group I: 130 (SEM 3)%; group II: 135 (SEM 6)%) side of controls (Mann-Whitney U test, p<0.01). No significant correlation (Spearman rank test) was found between the degree of group I and group II induced facilitations on the spastic side of the patients and the degree of clinically assessed spasticity (Ashworth scale).Conclusion: These results reflect a facilitation of the transmission in the interneuronal pathway coactivated by group I and group II afferents, probably resulting from a change in their descending control in spastic hemiplegic patients. [ABSTRACT FROM AUTHOR]

The activity of 19 antibiotics and four antiseptics and/or disinfectants was studied against 138 non-redundant strains of Aeromonas spp. (104 Aeromonas caviae, 22 Aeromonas sobria and 12 Aeromonas hydrophila) isolated from two European rivers. Antibiotic resistance frequencies were: nalidixic acid, 59%; tetracycline, 14%; fosfomycin, 8%; tobramycin and cotrimoxazole, 7%; cefotaxime, 4%; chloramphenicol, 2%; gentamicin, 1%. Most of the nalidixic acid-resistant strains were susceptible to fluoroquinolones (54–98%). Antibiotic resistance rates varied according to the source of the strains. All Aeromonas spp. strains were killed by 50 ppm of chlorine, cetylpyridinium chloride and peracetic acid, and by 1600 ppm of glutaraldehyde. [ABSTRACT FROM PUBLISHER]

Objective: To evaluate variables associated with quality of life (QOL) in dementia residents in a long-term care facility using a recently standardized and validated dementia-specific QOL scale (ADRQL).Method: A cross-sectional, case-control design was employed using validated scales to assess dementia-related symptomatology. Thirty-two facility staff members were interviewed to assess the QOL of 120 patients meeting DSM-IV for dementia criteria residing in long-term care.Results: ADRQL scores were higher in assisted living residents than in skilled nursing facility residents. In univariate analyses, worse orientation, greater physical dependency, depression, and treatment with anxiolytics were associated with lower ADRQL scores. In multivariate analyses, lower scores were associated with worse orientation, greater physical dependency, depression, and anxiolytic treatment.Conclusions: Residents exhibited better QOL than expected. Future longitudinal studies should address if reorientation, activity therapy, treatment of depression, and avoidance of benzodiazepines might improve QOL in this population. Interventions that might improve orientation and physical abilities, such as cholinomimetic therapies, psychosocial interventions, or behavioral strategies, should also be studied in future research on QOL. [ABSTRACT FROM AUTHOR]

The bactericidal activity of a pulsed fibre-optic Nd-YAP laser on various strains of oral bacteria: Prevotella nigrescens, Streptococcus sanguis, Actinomyces viscosus (i), Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans and Peptostreptococcus micros (i) was evaluated. A 200-μm optical fibre was placed in Eppendorf tubes containing the different bacterial suspensions. At an energy of 170 mJ/30 Hz, 351 pulses of 150 μs were sufficient to kill the most resistant bacteria (i). The exposure time was 28 s. The temperature rise caused by the shots were measured in vitro at the surface of the roots of two groups of 10 single-rooted teeth. One group received 350 pulses; for the other the preparation time was fixed at 28 s. The temperature rose by 25.66°C for the first group and 25.25°C for the second. [ABSTRACT FROM AUTHOR]

Objective: To assess the motor function of the left, supposedly unaffected, limbs of patients with an acute right vascular hemiplegia.Methods: Fifteen patients with an acute vascular right hemiplegia and 16 matched healthy controls were studied. Motor function of the left limbs of each patient was evaluated on days 20 and 90 after their stroke using four validated tools (hand dynamometer, isokinetic dynamometer, finger tapping, and nine hole peg test).Results: There was a significant impairment of motor function of the left limbs of patients at day 20 compared with controls. The impairment had recovered almost completely at day 90 after the stroke.Conclusion: These results show the bilateral cerebral representation of the human motor system and suggest the participation of ipsilateral motor pathways in recovery after a stroke. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii specific IgA and IgM antibodies were quantitated by an antibody capture agglutination assay in 260 patients with acquired toxoplasmosis and from 94 fetuses suspected of congenital toxoplasmosis and 30 infected children. In acquired toxoplasmosis, IgA antibodies to T gondii were found in 95% of the cases. In congenital toxoplasmosis IgA antibodies were more frequently detected (75%) in cord blood than IgM antibodies (61%). They persisted after birth, in some cases for up to 24 months. IgA antibodies were also detected in fetuses whose mothers had toxoplasmosis during their pregnancy. In infected fetuses IgM and IgA antibodies were detected in fetal blood as early as week 24 of pregnancy. Detection of IgA T gondii antibodies may be useful for the diagnosis of some recently acquired infection and for the diagnosis and follow up of the infection in the fetus and neonate. [ABSTRACT FROM PUBLISHER]

We screened about a hundred microorganisms (including unidentified yeasts, fungi, and bacteria) for their ability to produce xylanolytic enzymes. About 40 of them were hemicellulolytic; among these, we selected Penicillium canescens 10- 10c for detailed study because of its ability to produce an interesting enzymatic complex in quantity. The xylanase complex was cellulase-free, and had an optimal activity at pH 4.6–5.0 and 55–60‡C on birchwood xylan. The best production was on soya meal and wheat straw; expression of the xylanase was repressed by glucose, xylose, and lactose. The optimization of culture medium and mode (fed-batch) enabled us to improve the production three to four times. The importance of the mixing conditions on the biomass and xylanase production is also reported. [ABSTRACT FROM AUTHOR]

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