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Test Period (test + period)
Selected AbstractsThreshold electrical stimulation (TES) in ambulant children with CP: a randomized double-blind placebo-controlled clinical trialDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2002Christineí Dali MD A randomized double-blind placebo-controlled clinical trial was carried out to determine whether a group of stable children with cerebral palsy (36 males, 21 females; mean age 10 years 11 months, range 5 to 18 years) would improve their motor skills after 12 months of threshold electrical stimulation (TES). Two thirds received active and one third received inactive stimulators. For the primary outcome we constructed a set of plausible motor function tests and studied the change in summary indices of the performance measurements. Tests were videotaped and assessed blindly to record qualitative changes that might not be reflected in performance measurements. We also judged range of motion, degree of spasticity, and muscle growth measured by CT. Fifty seven of 82 outpatients who were able to walk at least with a walker, completed all 12 months of treatment (hemiplegia n=25, diplegia n=32). There was no significant difference between active and placebo treatment in any of the tested groups, nor combined. Visual and subjective assessments favoured TES (ns), whereas objective indices showed the opposite trend. We conclude that TES in these patients did not have any significant clinical effect during the test period. [source] Evaluation of dietary effects of transgenic corn pollen expressing Cry3Bb1 protein on a non-target ladybird beetle, Coleomegilla maculataENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2-3 2002Jian J. Duan Abstract A transgenic corn event (MON 863) has been recently developed by Monsanto Company for control of corn rootworms, Diabrotica spp. (Coleoptera: Chrysomelidae). This transgenic corn event expresses the cry3Bb1 gene derived from Bacillus thuringiensis (Berliner), which encodes the insecticidal Cry3Bb1 protein for corn rootworm control. A continuous feeding study was conducted in the laboratory to evaluate the dietary effect of MON 863 pollen expressing the Cry3Bb1 protein on the survival, larval development, and reproductive capacity of the non-target species, Coleomegilla maculata DeGeer (Coleoptera: Coccinellidae). First instar C. maculata (less than 24 h old) and newly emerging adults (less than 72 h old) were fed individually on a diet mixture containing 50% of MON 863 pollen, non-transgenic (control) corn pollen, bee pollen (a component of normal rearing diet), or potassium arsenate-treated control corn pollen. In the larval tests, 96.7%, 90.0%, and 93.3% of C. maculata larvae successfully pupated and then emerged as adults when fed on MON 863 pollen, non-transgenic corn pollen, and bee pollen (normal rearing) diets, respectively. Among the larvae completing their development, there were no significant differences in the developmental time to pupation and adult emergence among the transgenic corn pollen, non-transgenic corn pollen, and bee pollen diet treatments. All larvae fed on arsenate treated corn pollen diet died as larvae. For tests with adults, 83.3%, 80.0%, and 100% of adult C. maculata survived for the 30 days of the test period when reared on diets containing 50% of MON 863 pollen, non-transgenic corn pollen, and bee pollen respectively. While the adult survival rate on MON 863 pollen diet was significantly less than that on the bee pollen diet, there was no significant difference between the MON 863 and non-transgenic corn pollen treatments. During the period of adult testing, an average of 77, 80, and 89 eggs per female were laid by females fed on the MON 863 pollen, control corn pollen, and bee pollen, respectively; no significant differences were detected in the number of eggs laid among these treatments. These results demonstrate that when offered at 50% by weight of the dietary component, transgenic corn (MON 863) pollen expressing Cry3Bb1 protein had no measurable negative effect on the survival and development of C. maculata larvae to pupation and adulthood nor any adverse effect on adult survival and reproductive capacity. Relevance of these findings to ecological impacts of transgenic Bt crops on non-target beneficial insects is discussed. [source] Uptake kinetics and subcellular compartmentalization of cadmium in acclimated and unacclimated earthworms (Eisenia andrei)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2010Shuo Yu Abstract Acclimation to cadmium (Cd) levels exceeding background concentrations may influence the ability of earthworms to accumulate Cd with minimum adverse effects. In the present study, earthworms (Eisenia andrei) were acclimated by exposure to 20,mg/kg Cd (dry wt) in Webster soil for 28 d. A 224-d bioaccumulation test was subsequently conducted with both acclimated and unacclimated worms exposed in Webster soils spiked with 20,mg/kg and 100,mg/kg Cd (dry wt). Uptake kinetics and subcellular compartmentalization of Cd were examined. Results suggest that acclimated earthworms accumulated more Cd and required a longer time to reach steady state than unacclimated worms. Most of the Cd was present in the metallothionein (MT) fraction. Cadmium in the MT fraction increased approximately linearly with time and required a relatively longer time to reach steady state than Cd in cell debris and granule fractions, which quickly reached steady state. Cadmium in the cell debris fraction is considered potentially toxic, but low steady state concentrations observed in the present study would not suggest the potential for adverse effects. Future use of earthworms in ecological risk assessment should take into consideration pre-exposure histories of the test organisms. A prolonged test period may be required for a comprehensive understanding of Cd uptake kinetics and compartmentalization. Environ. Toxicol. Chem. 2010;29:1568,1574. © 2010 SETAC [source] Aquatic toxicity of triclosanENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002David R. Orvos Abstract The aquatic toxicity of triclosan (TCS), a chlorinated biphenyl ether used as an antimicrobial in consumer products, was studied with activated-sludge microorganisms, algae, invertebrates, and fish. Triclosan, a compound used for inhibiting microbial growth, was not toxic to wastewater microorganisms at concentrations less than aqueous solubility. The 48-h Daphnia magna median effective concentration (EC50) was 390 ,g/L and the 96-h median lethal concentration values for Pimephales promelas and Lepomis macrochirus were 260 and 370 ,g/L, respectively. A no-observed-effect concentration (NOEC) and lowest-observed-effect concentration of 34.1 ,g/L and 71.3 ,g/L, respectively, were determined with an early life-stage toxicity test with Onco-rhynchus mykiss. During a 96-h Scenedesmus study, the 96-h biomass EC50 was 1.4 ,g/L and the 96-h NOEC was 0.69 ,g/L. Other algae and Lemna also were investigated. Bioconcentration was assessed with Danio rerio. The average TCS accumulation factor over the five-week test period was 4,157 at 3 ,g/L and 2,532 at 30 ,g/L. Algae were determined to be the most susceptible organisms. Toxicity of a TCS-containing wastewater secondary effluent to P. promelas and Ceriodaphnia was evaluated and no observed differences in toxicity between control and TCS-treated laboratory units were detected. The neutral form of TCS was determined to be associated with toxic effects. Ionization and sorption will mitigate those effects in the aquatic compartment. [source] Effect of varying pesticide exposure duration and concentration on the toxicity of carbaryl to two field-collected stream invertebrates, Calineuria californica (Plecoptera: Perlidae) and Cinygma sp. (Ephemeroptera: Heptageniidae)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2001Jennifer L. Peterson Abstract The effect of exposure duration on the toxicity of a forest insecticide (carbaryl) was assessed under environmentally realistic exposure regimes against two stream invertebrates indigenous to the United States Pacific Northwest, Calineuria californica (Plecoptera: Perlidae) and Cinygma sp. (Ephemeroptera: Heptageniidae). Laboratory bioassays were conducted to evaluate the relationship between pulsed exposures of 15, 30, and 60 min and toxicity for a range of chemical concentrations (10.2,1,730 ,g/L). For Cinygma sp., the 50% lethal concentration (LC50) values were calculated as 848 ,g/L (15 min), 220 ,g/L (30 min), and 165 ,g/L (60 min). The C. californica consistently had lower mortality at a given concentration compared with Cinygma sp. Fifteen- and 30-min exposures did not elicit 50% mortality with C. californica, and it had a 60-min LC50 of 1,139 ,g/L. Time to 50% mortality over 96 h after a 15-, 30-, or 60-min exposure, with the rest of the test period in freshwater (PLT50), was a function of exposure duration and concentration. Analysis of symptomology throughout the test period for C. californica gave evidence of recovery from the knockdown and moribund states, but this was not the case for Cinygma sp. The pulse duration resulting in 50% mortality was calculated as 43 min for Cinygma sp. exposed at 204 ,g/L and 16 min at 408 ,g/L. A three-dimensional probit plane model [Y = , 10.86 + 4.83(In C) + 3.0(In T)], where Y is probit mortality, C is concentration in ,g/L and T is time in hours, was used to explain the interaction between concentration (,g/L) and duration of exposure (hours) for Cinygma sp. [source] A test of the community conditioning hypothesis: Persistence of effects in model ecological structures dosed with the jet fuel jp-8ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2000Wayne G. Landis Abstract The foundation of the community conditioning hypothesis, the persistence of effects, was tested in a series of microcosm experiments. Experiments were conducted with the water-soluble fraction of the turbine fuel JP-8 using the standard protocols for the standardized aquatic microcosm (SAM). A repeat trial was conducted using the SAM protocol but with a 126-d test period, twice the standard duration. The results were examined using a variety of conventional univariate, multivariate, and graphical techniques. The principal conclusions were as follows. Effects are persistent in these model ecological systems long after the degradation of the toxicant. Patterns of impacts are detectable at concentrations 15 times lower than an experimentally derived single-species EC50. The replicate experiments are not replicable in the specific, but the broad pattern of the disruption of algal- herbivore dynamics followed by more subtle effects are consistently repeated. The durability of the indirect effects and therefore the information about historical events appears to be a consistent feature of these microcosm systems. The identity of the treatment groups persists. The critical features of the community conditioning hypothesis,persistence of information within ecologicalsystems and the reappearance of patterns and therefore the nonequilibrium dynamics,are again confirmed. The implications of these findings for environmental toxicology, monitoring, and ecological risk assessment are discussed. [source] MDMA self-administration in rats: acquisition, progressive ratio responding and serotonin transporter bindingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2007Susan Schenk Abstract 3,4-Methylenedioxymethamphetamine (MDMA) self-administration has been shown in animals with extensive drug histories, but only a small number of studies have examined high rates of responding maintained by MDMA in previously drug-naïve animals. In the present study, influence of dose (0.25 or 1.0 mg/kg/infusion) on the acquisition of MDMA self-administration was measured during daily 6-h sessions. Dose,effect data were obtained for MDMA (0.25,1.0 mg/kg/infusion) self-administration under a progressive ratio (PR) schedule of reinforcement. The effect of experimenter- or self-administered MDMA on [3H] paroxetine binding in several brain regions was measured. Acquisition of MDMA self-administration was highly variable and not different for 0.25 or 1.0 mg/kg/infusion progressed with approximately 60% of the rats acquiring reliable self-administration during the 15-day test period. The percentage of rats that acquired MDMA self-administration was lower than the percentage of rats that acquired cocaine (0.5 mg/kg/infusion) self-administration, and cocaine self-administration was acquired with a shorter latency. Responding maintained by MDMA was dose dependent, and breakpoints under a PR schedule increased with dose. Radioligand binding and autoradiography demonstrated lower densities of serotonin transporter sites (SERT) in MDMA self-administering rats as compared with controls across brain regions. The reduction in SERT densities was comparable in magnitude to rats treated with experimenter-administered doses of MDMA. These data support the idea that MDMA is a drug with high abuse liability, and long-term self-administration may lead to long-lasting deficits in serotonin neurotransmission. [source] Small-scale fluid motion mediates growth and nutrient uptake of Selenastrum capricornutumFRESHWATER BIOLOGY, Issue 6 2006T. A. WARNAARS Summary 1. A fluid-flow reactor using submersible speakers was constructed to generate small-scale fluid motion similar to conditions measured in open water environments; flow was quantified by particle image velocimetry. Additionally a Couette-type rotating cylinder was used to generate shear flows; flow was quantified using an optical hotwire probe and torque measurements. Growth rates of the green alga Selenastrum capricornutum were determined from changes in cell counts and viability was tested using the fluorogenic probe fluoresceine diacetate. 2. Evidence that fluid motion directly affects growth rates was obtained as a significant difference between growth in a moving versus non-moving fluid. A near 2-fold increase in growth rate was achieved for an energy dissipation rate of , = 10,7 m2 s,3; a rate common in lakes and oceans. The onset of the viability equilibrium, identified as the day of the test period when the number of active cells equalled non-active cells, was delayed by 2 days for moving fluid conditions as compared with a non-moving fluid. 3. Nutrient uptake was determined by a decrease in the bulk fluid concentration and cellular phosphorus concentration was also estimated. The thickness of the diffusive sublayer surrounding a cell, a zone dominated by molecular diffusion, was estimated. Increasing fluid motion was found to decrease the thickness of this layer. The Sherwood number (ratio of total mass flux to molecular mass flux) showed that advective flux surrounding cells dominated molecular diffusion flux with regard to Péclet numbers (ratio of advective transport to molecular diffusion transport). Fluid motion facilitated uptake rates and resulted in increased growth rates, compared with no-flow conditions. The rate-of-rotation and the rate-of-strain in a moving fluid equally mediated the diffusive sublayer thickness surrounding the cells. Our study demonstrates that small-scale fluid motion mediates algal growth kinetics and therefore should be included in predictive models for algal blooms. [source] How to model shallow water-table depth variations: the case of the Kervidy-Naizin catchment, FranceHYDROLOGICAL PROCESSES, Issue 4 2005Jérôme Molénat Abstract The aim of this work is threefold: (1) to identify the main characteristics of water-table variations from observations in the Kervidy-Naizin catchment, a small catchment located in western France; (2) to confront these characteristics with the assumptions of the Topmodel concepts; and (3) to analyse how relaxation of the assumptions could improve the simulation of distributed water-table depth. A network of piezometers was installed in the Kervidy-Naizin catchment and the water-table depth was recorded every 15 min in each piezometer from 1997 to 2000. From these observations, the Kervidy-Naizin groundwater appears to be characteristic of shallow groundwaters of catchments underlain by crystalline bedrock, in view of the strong relation between water distribution and topography in the bottom land of the hillslopes. However, from midslope to summit, the water table can attain a depth of many metres, it does not parallel the topographic surface and it remains very responsive to rainfall. In particular, hydraulic gradients vary with time and are not equivalent to the soil surface slope. These characteristics call into question some assumptions that are used to model shallow lateral subsurface flow in saturated conditions. We investigate the performance of three models (Topmodel, a kinematic model and a diffusive model) in simulating the hourly distributed water-table depths along one of the hillslope transects, as well as the hourly stream discharge. For each model, two sets of parameters are identified following a Monte Carlo procedure applied to a simulation period of 2649 h. The performance of each model with each of the two parameter sets is evaluated over a test period of 2158 h. All three models, and hence their underlying assumptions, appear to reproduce adequately the stream discharge variations and water-table depths in bottom lands at the foot of the hillslope. To simulate the groundwater depth distribution over the whole hillslope, the steady-state assumption (Topmodel) is quite constraining and leads to unacceptable water-table depths in midslope and summit areas. Once this assumption is relaxed (kinematic model), the water-table simulation is improved. A subsequent relaxation of the hydraulic gradient (diffusive model) further improves water-table simulations in the summit area, while still yielding realistic water-table depths in the bottom land. Copyright © 2004 John Wiley & Sons, Ltd. [source] Performance comparison of some dynamical and empirical downscaling methods for South Africa from a seasonal climate modelling perspectiveINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2009Willem A. Landman Abstract The ability of advanced state-of-the-art methods of downscaling large-scale climate predictions to regional and local scale as seasonal rainfall forecasting tools for South Africa is assessed. Various downscaling techniques and raw general circulation model (GCM) output are compared to one another over 10 December-January-February (DJF) seasons from 1991/1992 to 2000/2001 and also to a baseline prediction technique that uses only global sea-surface temperature (SST) anomalies as predictors. The various downscaling techniques described in this study include both an empirical technique called model output statistics (MOS) and a dynamical technique where a finer resolution regional climate model (RCM) is nested into the large-scale fields of a coarser GCM. The study addresses the performance of a number of simulation systems (no forecast lead-time) of varying complexity. These systems' performance is tested for both homogeneous regions and for 963 stations over South Africa, and compared with each other over the 10-year test period. For the most part, the simulations method outscores the baseline method that uses SST anomalies to simulate rainfall, therefore providing evidence that current approaches in seasonal forecasting are outscoring earlier ones. Current operational forecasting approaches involve the use of GCMs, which are considered to be the main tool whereby seasonal forecasting efforts will improve in the future. Advantages in statistically post-processing output from GCMs as well as output from RCMs are demonstrated. Evidence is provided that skill should further improve with an increased number of ensemble members. The demonstrated importance of statistical models in operation capacities is a major contribution to the science of seasonal forecasting. Although RCMs are preferable due to physical consistency, statistical models are still providing similar or even better skill and should still be applied. Copyright © 2008 Royal Meteorological Society [source] Recalibration of general circulation model output to austral summer rainfall over southern AfricaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2003A. G. Bartman Abstract Empirical techniques are developed to adjust dynamic model forecasts on the seasonal time scale for southern African summer rainfall. The techniques, perfect prognosis and model output statistics (MOS), are utilized to ,recalibrate' the CSIRO 9 general circulation model (GCM) large-scale fields statistically to three equi-probable rainfall categories for December to February. The recalibration is applied to a GCM experiment where simultaneously observed sea-surface temperature fields serve as the lower boundary forcing. An optimal canonical correlation analysis model is designed for MOS and perfect prognosis and the 700 hPa geopotential height field is selected as the single predictor field in the two sets of statistical equations that are subsequently used to produce recalibrated rainfall simulations over a 10 year independent test period. MOS produced the higher forecast skill for southern Africa over the independent test period. Copyright © 2003 Royal Meteorological Society [source] Skin moisturization by hydrogenated polyisobutene,Quantitative and visual evaluationINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2010N. Dayan J. Cosmet. Sci., 60, 15,24 (January/February 2009) Synopsis Hydrogenated polyisobutene (HP) is used in topically applied cosmetic/personal care formulations as an emollient that leaves a pleasing skin feel when applied, and rubbed in after application. This effect, although distinguishable to the user, is difficult to define and quantify. Recognizing that some of the physical properties of HP such as film formation and wear resistance may contribute, in certain mechanisms, to skin moisturization, we designed a short-term pilot study to follow changes in skin moisturization. HP's incorporation into an o/w emulsion at 8% yielded increased viscosity and reduced emulsion droplet size as compared to the emollient ester CCT (capric/caprylic triglyceride) or a control formulation. Quantitative data indicate that application of the o/w emulsion formulation containing either HP or CCT significantly elevated skin moisture content and thus reduced transepidermal water loss (TEWL) by a maximal ,33% against the control formulation within 3 h and maintained this up to 6 h. Visual observation of skin treated with the HP-containing formulation showed fine texture and clear contrast as compared to the control or the CCT formulation, confirming this effect. As a result of increased hydration, skin conductivity, as measured in terms of corneometer values, was also elevated significantly by about tenfold as early as 20 min after HP or CCT application and was maintained throughout the test period. Throughout the test period the HP formulation was 5,10% more effective than the CCT formulation both in reduction of TEWL as well as in increased skin conductivity. Thus, compared to the emollient ester (CCT), HP showed a unique capability for long-lasting effect in retaining moisture and improving skin texture. [source] Optimized management of genetic variability in selected pig populationsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 5 2008J.J. Colleau Summary Controlling the increase of coancestry and inbreeding coefficients in selected populations is made possible through calculation of the optimal contributions allowed to breeding animals, given the current situation with regard to genetic diversity, and further, through optimal design of matings. The potential of such an approach for pig breeding was tested by retrospective optimization on the French Landrace population in reference to the matings actually carried out during a 21-week test period. The major constraint was that the average overall estimated breeding value (EBV) should be the same as the observed one, for not decreasing short-term genetic gain. Optimizing breeding allocations to boars would have led one to decrease coancestry and inbreeding coefficients by approximately 20%. This decrease would have even increased to approximately 30%, would have replacements and disposals been optimized after accounting for genetic variability, keeping the same constraint of genetic level identical to the observed one. These results showed the potential value, in the future, of completing each periodical calculation of EBVs by optimizations considering genetic variability and of releasing corresponding information to breeders, in order to enhance maintenance of genetic variability. [source] Variance components due to direct genetic, maternal genetic and permanent environmental effect for growth and feed-efficiency traits in young male Japanese Black cattleJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 3 2007M. A. Hoque Summary Variance components and genetic parameters were estimated using data recorded on 740 young male Japanese Black cattle during the period from 1971 to 2003. Traits studied were feed intake (FI), feed-conversion ratio (FCR), residual feed intake (RFI), average daily gain (ADG), metabolic body weight (MWT) at the mid-point of the test period and body weight (BWT) at the finish of the test (345 days). Data were analysed using three alternative animal models (direct, direct + maternal environmental, and direct + maternal genetic effects). Comparison of the log likelihood values has shown that the direct genetic effect was significant (p < 0.05) for all traits and that the maternal environmental effects were significant (p < 0.05) for MWT and BWT. The heritability estimates were 0.20 ± 0.12 for FI, 0.14 ± 0.10 for FCR, 0.33 ± 0.14 for RFI, 0.19 ± 0.12 for ADG, 0.30 ± 0.14 for MWT and 0.30 ± 0.13 for BWT. The maternal effects (maternal genetic and maternal environmental) were not important in feed-efficiency traits. The genetic correlation between RFI and ADG was stronger than the corresponding correlation between FCR and ADG. These results provide evidence that RFI should be included for genetic improvement in feed efficiency in Japanese Black breeding programmes. [source] Influence of a SLS-containing dentifrice on the anti-plaque efficacy of a chlorhexidine mouthrinseJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2004D. A. C. Van Strydonck Abstract Background: Chlorhexidine (CHX) and sodium lauryl sulphate (SLS), the most widely used detergent in dentifrice, may counteract. Consequently, studies about this interaction suggested that care is required when combining both these compounds, even when they are introduced separately into the oral cavity. The purpose of the present study was to investigate the effect of toothbrushing with a SLS-containing dentifrice in one jaw, on the plaque inhibition of a CHX mouthrinse in the opposite jaw during a 4-day study period. Methods: The study was an examiner-blind, randomised two-cell, crossover design. It used a 4-day plaque accumulation model to compare two different oral hygiene regimens with a washout period of 17 days. Sixteen healthy volunteers were enrolled in the study and received a thorough dental prophylaxis at the beginning of each 4-day test period. One jaw (upper or lower) was randomly assigned as the "study" jaw. The opposite jaw was assigned as the "dentifrice" jaw and served only to introduce the effect of brushing with a dentifrice in the study model. Two oral hygiene regimens were evaluated. During one randomly assigned test period, the "dentifrice" jaw was treated by toothbrushing with a 1.5% SLS-containing dentifrice and rinsed together with the "study" jaw with 0.2% CHX, thus forming regimen 1. As a control during the other test period, both the "dentifrice" jaw and "study" jaw were only rinsed with 0.2% CHX, forming regimen 2. No other oral hygiene methods were allowed. After 4 days of undisturbed plaque accumulation, the amount of plaque was evaluated (Silness & Löe 1964). The "study" jaw was used to study the effect of the two regimens on the level of plaque accumulation at the end of the 4-day period. Results: The overall plaque index was 0.36 for regimen 1 and 0.34 for regimen 2. There was no significant difference in plaque accumulation between the two regimens. Conclusions: Within the limitations of the present study design, it can be concluded that ordinary brushing with a 1.5% SLS-containing dentifrice (Colgate Bi-Fluor), followed by rinsing with water does not appear to reduce the level of plaque inhibition offered by a post-brushing CHX rinse. [source] Some soft tissue characteristics at implant abutments with different surface topographyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2003A study in humans Abstract Background: If an implant with a rough surface is exposed to the oral cavity, it may accumulate greater amounts of plaque than a smooth surface, which may lead to severe problems with mucositis and peri-implantitis. The purpose of the present paper was to investigate the early inflammatory response to mucosa-penetrating abutments prepared with varying surface roughness. Methods: Nine patients had all five of their original abutments exchanged to test abutments for a 4-week period. The test abutments were prepared with five different roughnesses. The surface roughness was measured with an optical profilometer. At the end of the test period, clinical evaluation was performed; the health of the surrounding mucosa, the amount of accumulated plaque and marginal bleeding were registered. One biopsy was taken from each test abutment. Qualitative and quantitative histological evaluations were performed. Results: There was a statistically significant difference between patients regarding the amount of accumulated plaque on the abutment surfaces and inflammatory cells, but no difference between the surface modifications in relation to plaque accumulation or number of inflammatory cells. Conclusion: No relation was found between inflammatory response and abutment surface roughness after an evaluation time of 4 weeks in a human test model. Zusammenfassung Hintergrund: Wenn ein Implantat mit einer rauhen Oberfläche der Mundhöhle ausgesetzt wird, kann es zu stärkerer Plaqueakkumulation kommen als bei glatten Oberflächen, was zu ernsthaften Problemen mit Mukositis und Periimplantitis führen kann. Zielsetzung: Untersuchung der frühen Entzündungsreaktion auf durch die Schleimhaut tretende Implantatpfeiler mit unterschiedlicher Oberflächenrauhigkeit. Methoden: Bei jedem von 9 Patienten wurden alle 5 ursprünglichen Implantatpfeiler für einen Zeitraum von 4 Wochen gegen Testpfeiler ausgetauscht. Die Testpfeiler waren jeweils mit unterschiedlichen Oberflächenrauhigkeiten präpariert. Die Rauhigkeiten waren mit einem Profilometer gemessen worden. Am Ende des Untersuchungszeitraumes wurden klinische Parameter bestimmt: der Zustand der periimplantären Mukosa, die Menge der akkumulierten Plaque und marginales Bluten. An jedem Pfeiler wurde eine Biopsie entnommen, die jeweils qualitativ und quantitativ histologisch ausgewertet wurde. Ergebnisse: Es bestanden statistisch signifikante interindividuelle Unterschiede zwischen den Patienten hinsichtlich abgelagerter Plaque und Zahl der Entzündungszellen an den Implantatpfeilern, aber keine diesbezüglichen intraindividuellen Unterschiede zwischen den verschiedenen Oberflächenrauhigkeiten. Schlussfolgerung: In einem menschlichen Versuchsmodell wurden über einen Zeitraum von 4 Wochen keine Beziehungen zwischen Entzündungsreaktion und Implantatpfeileroberflächenrauhigkeit beobachtet. Résumé Origine: Lorsqu'un implant à surface rugueuse est exposé dans la cavité buccale, il peut accumuler davantage de plaque qu'une surface lisse, ce qui peut conduire à des problèmes graves associés à une mucite ou une péri-implantite. Le but de cette étude était d'examiner la réponse inflammatoire précoce aux implants pénétrant la muqueuse et ayant une rugosité de surface variable. Méthodes: Les cinq implants d'origine de chacun des neuf patients ont été remplacés par des implants expérimentaux pour une période de quatre semaines. Ces implants expérimentaux ont été conçus avec cinq rugosités différentes. La rugosité de surface a été mesurée à l'aide d'un profilomètre optique. A l'issue de la période expérimentale, une évaluation clinique a été réalisée: l'état de la muqueuse environnante, la quantité de plaque accumulée et le saignement marginal ont été relevés. Une biopsie a été prélevée sur chaque implant expérimental et des évaluations histologiques qualitatives et quantitatives ont été faites. Résultats: Il y avait une différence statistiquement significative entre les patients en ce qui concerne la quantité de plaque accumulée à la surface des implants et les cellules inflammatoires, mais aucune différence entre les modifications de surface en rapport avec l'accumulation de plaque ou le nombre de cellules inflammatoires. Conclusion: Aucune relation n'a étéétablie entre la réponse inflammatoire et la rugosité de surface des implants au bout de quatre semaines d'évaluation dans un modèle expérimental humain. Mots clés: Pilier d'implant; réponse des tissus mous; étude clinique; histologie. [source] Active Packaging of Fresh Chicken Breast, with Allyl Isothiocyanate (AITC) in Combination with Modified Atmosphere Packaging (MAP) to Control the Growth of PathogensJOURNAL OF FOOD SCIENCE, Issue 2 2010Joongmin Shin ABSTRACT:,Listeria monocytogenes,and,Salmonella typhimurium,are major bacterial pathogens associated with poultry products. Ally isothiocyanate (AITC), a natural antimicrobial compound, is reportedly effective against these pathogenic organisms. A device was designed for the controlled release of AITC with modified atmosphere packaging (MAP), and then evaluated for its ability to control the growth of,L. monocytogenes,and,S. typhimurium,on raw chicken breast during refrigerated storage. In order to obtain controlled release during the test period, a glass vial was filled with AITC and triglyceride. It was then sealed using high-density polyethylene film. The release of AITC was controlled by the concentration (mole fraction) of AITC in the triglyceride and by the AITC vapor permeability through the film. The fresh chicken samples were inoculated with one or the other of the pathogens at 104 CFU/g, and the packages (with and without AITC-controlled release device) were flushed with ambient air or 30% CO2/70% N2 before sealing, and then stored at 4 °C for up to 21 d. The maximum reduction in MAP plus AITC (compared to MAP alone) was 0.77 log CFU/g for,L.,monocytogenes,and 1.3 log CFU/g for,S.,typhimurium. The color of the chicken breast meat was affected by the concentration of AITC. Overall, a release rate of 0.6 ,g/h of AITC was found to not affect the color, whereas at 1.2 ,g/h of AITC the surface of the chicken was discolored. [source] Effect of an antifungal denture liner on the saliva yeast count in patients with denture stomatitis: a pilot studyJOURNAL OF ORAL REHABILITATION, Issue 9 2008G. A. V. M. GEERTS Summary, Although in vitro studies on the release of antifungal agents from tissue conditioners have been done, no in vivo research on the topic could be found. The purpose of this study was to determine the in vivo effect of an antifungal agent released from a tissue conditioner on the salivary yeast count. Forty edentulous patients with denture stomatitis caused by Candida albicans were divided in two groups. Group 1 (control) was treated with a tissue conditioner only. Group 2 was treated with a tissue conditioner incorporating 500 000 U nystatin. Oral rinses were performed by both groups before treatment and every second day during treatment for a period of 14 days. Total yeast counts of the oral rinses were performed and the averages and standard deviations for both groups calculated and logarithm-transformed data of the counts over time were statistically analysed using the Wilcoxon signed-rank test. The average oral rinse yeast count of the control group decreased up to day 4. Thereafter, the count increased till the end of the test period. At day 14, the oral rinse yeast level was higher than the pre-treatment level. The average yeast count of the test group decreased up to day 7. Thereafter, the count increased but remained significantly lower (P = 0·01) than the control group and did not return to its pre-treatment level. A nystatin-containing short-term denture liner significantly decreases the salivary yeast count of patients with denture stomatitis compared with a liner without nystatin. [source] Leaf Disc Inoculation, a Fast and Precise Test for the Screening of Metalaxyl Tolerance in Sunflower Downy MildewJOURNAL OF PHYTOPATHOLOGY, Issue 6 2001B. Rozynek A new method, based on leaf disc inoculation, was developed for the screening of metalaxyl tolerance in field isolates of Plasmopara halstedii. High-pressure liquid chromatography (HPLC) was used to determine the fungicide concentration in the inoculation medium and in the incubated leaf tissue over the test period. These measurements revealed that the fungicide concentration inside the leaf tissue within 24 h had adjusted to the concentration in the outer medium and remained constant for the time of cultivation over a period of more than 11 days. In contrast to whole seedling tests with application of the fungicide via seed dressing, the leaf disc method allows precise quantification of the effective fungicide concentration at the site of infection and is less space and time consuming. Metalaxyl tolerance of P. halstedii isolates was gradually determined according to the sporulation of the pathogen on sunflower leaf discs in the presence of increasing fungicide concentrations. Isolates collected in South Germany showed no tolerance and sporulation was prohibited when tests were carried out at 0.02 ,g (a.i.)/ml of metalaxyl or more. In contrast, a tolerant French isolate developed sporangia on leaf discs incubated in a metalaxyl solution of 100 ,g (a.i.)/ml. [source] Long-Lasting Resistance to Extinction of Response Reinstatement Induced by Ethanol-Related Stimuli: Role of Genetic Ethanol PreferenceALCOHOLISM, Issue 10 2001Roberto Ciccocioppo Background: The conditioning of ethanol's reinforcing effects with specific environmental stimuli is thought to be a critical factor in long-lasting relapse risk associated with alcoholism. To study the significance of such learning factors in the addictive potential of ethanol, this experiment was designed (1) to characterize the effects of stimuli associated with alcohol availability on the reinstatement of responding at a previously ethanol-paired lever in rats with genetically determined ethanol preference versus nonpreference and (2) to examine the persistence of the motivating effects of these stimuli over time. Methods: Male alcohol-preferring (P) and alcohol-nonpreferring (NP) rats were trained to operantly self-administer ethanol (10% w/v) or water on a fixed-ratio 1 schedule in a 30-min daily session. Ethanol and water sessions were scheduled in random sequence across training days. Ethanol availability was signaled by an olfactory discriminative stimulus (banana extract, S+), and each lever press was paired with brief presentation of the conditioning chamber's house light (CS+). The discriminative stimulus signaling water availability (i.e., nonreward) consisted of anise odor (S,), and lever-responses during water sessions were paired with a brief white noise generation (CS,). The rats then were placed on extinction conditions during which ethanol and water, as well as the corresponding stimuli, were withheld. The effects of noncontingent exposure to the S+ versus S, paired with response-contingent presentation of the CS+ versus CS, on responding at the previously active lever were then determined in 30-min reinstatement sessions. To study the resistance to extinction of the effects of the ethanol-associated stimuli, additional tests were conducted at 3-day intervals for a total of 50 days. Results: The number of ethanol-reinforced responses during self-administration training was significantly greater in P than in NP rats (p < 0.01). After extinction, a significant recovery of responding was observed in both groups of rats under the stimulus conditions associated with ethanol (S+/CS+) but not those associated with water (S,/CS,). However, the response reinstatement was significantly greater in P than NP rats (p < 0.01). In addition, the results revealed a considerable resistance to extinction to the effects of the ethanol-associated stimuli. Throughout the 50-day test period, responding remained significantly above extinction levels in both P and NP rats (p < 0.01), but with an overall greater number of responses in P than NP rats (p < 0.05). Conclusions: The results support the hypothesis that conditioning factors contribute importantly to compulsive ethanol seeking and long-lasting vulnerability to relapse. In addition, the results suggest that genetic predisposition toward heightened ethanol intake extends to greater susceptibility to the motivating effects of ethanol-related environmental stimuli. [source] Fermentation of soybean by Rhizopus promotes the calcium absorption ratio in ratsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2008Nakamichi Watanabe Abstract BACKGROUND: Soy foods are generally considered to be an unfavourable source of calcium because soybean is rich in phytate, which retards the absorption of calcium. The objective of this study was to assess the effect of dietary fermented soybean, such as tempeh, on calcium absorption in rats. The rats were grouped into three dietary groups and fed the experimental diets for 4 weeks. Soybean, conventional tempeh prepared by aerobic fermentation with Rhizopus (tempeh), and novel tempeh prepared by aerobic and successive anaerobic fermentations (anaerobic tempeh) were used as the protein sources of the experimental diets. RESULTS: The order of the calcium absorption ratio for the 3 days before the end of the test period was as follows: tempeh group > anaerobic tempeh group > soybean group. CONCLUSION: The calcium absorption ratio of the tempeh group in particular was significantly higher than those of the other two groups. The high calcium absorption ratio of the tempeh group might be caused by both low phytate contents and peptides that are produced during the fermentation of soybean by Rhizopus. Copyright © 2008 Society of Chemical Industry [source] Assimilating humidity pseudo-observations derived from the cloud profiling radar aboard CloudSat in ALADIN 3D-VarMETEOROLOGICAL APPLICATIONS, Issue 4 2009Andrea Storto Abstract This paper describes an experimental procedure for assimilating CloudSat Cloud Profiling Radar (CPR) observations in ALADIN 3D-Var through the use of humidity pseudo-observations derived from a one-dimensional Bayesian analysis. Cloud data are considered as binary occurrences (,cloud' vs ,no-cloud'), which makes the approach feasible to be extended to other cloudiness observations, and to any other binary observation in general. A simple large-scale condensation scheme is used for projecting the prior information from a Numerical Weather Prediction model into cloud fraction space. Verification over a 1 month assimilation test period indicates a clear benefit of the pseudo-observation assimilation scheme for the limited CloudSat CPR data set, especially in terms of improved skill scores for dynamical parameters such as geopotential and wind. Copyright © 2008 Royal Meteorological Society [source] Psychosomatic tendency for suicide among the elderly in Mie Prefecture, JapanPSYCHOGERIATRICS, Issue 2 2007Ken INOUE Abstract Background:, The aim of the present study is to show the causative factors of suicide among the elderly (over 65) in Mie Prefecture, Japan, and to discuss the prevention of the suicidal influences in elderly patients. Methods:, We investigated all inquest records during the 14-year period 1989,2002 in cooperation with the First Department of Criminal Investigation of Mie Prefectural Police Headquarters. From all cases classified as suicides, we extracted data on age, sex and background, and we focused on suicide in the elderly group. Results:, During the test period, there were 5048 suicides (3276 male and 1772 female suicides) of which 1513 (691 male and 822 female) were in the elderly group. The rate of suicide in the elderly group was approximately 30% of the total in all age groups. The rate of female suicides in the elderly group was approximately 46.3%. The major causative factors of suicide among the elderly were ,suffering from physical illness', and ,psychiatric disorders'. ,Physical diseases' were not negligible backgrounds in middle and elderly groups. Among physical diseases, the number of malignant neoplasm was clearly less than the other diseases. Notably, ,cardiovascular disease' and ,orthopedic disorders' were most frequent causative factors of suicide other than malignant neoplasm. Conclusion:, It is consequently concluded that improvements in the system of home nursing and health care should be involved in the suicidal prevention of the elderly who ,suffer from physical illness'. The patients who ,suffer from physical illness' should be given physical and mental support. In order to prevent suicide, not only psychiatrists but also general practitioners as well as medical staff and general public should be provided with education regarding depression among ,psychiatric disorders'. [source] Comparative Study on Five Different Commercial Extenders for Boar SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2004P Vyt Contents Increasing interest in a longer preservation of diluted boar sperm raises questions in the field concerning the choice of the extender. The aim of this study was to evaluate the longevity of boar sperm extended in currently used commercial semen extenders. Three long-term extenders and two short-term extenders were compared for different semen quality parameters that can be assessed under routine laboratory conditions. Sperm morphology, motility, pH and bacteriological contamination were investigated during a 7-day period. The number of dead spermatozoa did not differ significantly among the extenders (p > 0.05). Sperm motility was not only related with storage period but most of all with pH, especially in long-term extenders. Differences between the different extenders were prominent (p < 0.05); the sperm preserved in only one long-term extender showed good motility during the whole test period. In all cases, the pH of the extended semen increased by 0.3,0.5 in the first days of storage and was significantly correlated with a decrease in motility. Bacteriological quality had no significant influence on motility or pH of the semen. In conclusion, we can state that in both short-term extenders and in only one long-term extender, sperm longevity, as evaluated by the parameters used in this study, was sufficient during the preservation period. To preserve the quality of diluted boar semen during long-term storage, the choice of the long-term extender is important. In addition, the monitoring of the pH of extended boar semen in our study emphasizes the importance of the buffering capacity of semen extenders. [source] An insertion/deletion variant of a thymine base in exon 2 of the porcine beta 3-adrenergic receptor gene associated with loin eye muscle areaANIMAL SCIENCE JOURNAL, Issue 6 2009Kensuke HIROSE ABSTRACT An insertion/deletion variant of a thymine base (T5 and T6) in exon 2 of porcine beta 3-adrenergic receptor (ADRB3) gene has been described. In the current study, we made an association study between the ADRB3 polymorphisms and production traits in 735 Duroc pigs. The allele frequencies for the T5 and T6 alleles in our study population were 0.433 and 0.567, respectively. Any associations between ADRB3 genotype and average daily weight gain during test period, or backfat thickness and intramuscular fat content were not detected in either sex. However the size of the loin eye muscle area (EMA) was significantly associated with ADRB3 genotypes in gilts. T6-homozygous gilts had a higher mean of EMA (40.6 ± 0.6 cm2) than T5-homozygous (38.1 ± 0.4 cm2, P = 0.002) and heterozygous (38.8 ± 0.3 cm2, P = 0.034) gilts. This association was not detected in males. In addition, a multiple traits animal model best linear unbiased predictor (BLUP) analysis revealed that the T6-homozygous genotype had positive effects on breeding value of EMA. Accordingly, we suggest that ADRB3 polymorphism has the potential to be an important genetic marker for prediction of EMA in Duroc pigs. [source] Detection of environmental androgens: A novel method based on enzyme-linked immunosorbent assay of spiggin, the stickleback (Gasterosteus aculeatus) glue proteinENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2002Ioanna Katsiadaki Abstract We report the development and validation of a novel in vivo biomarker test for waterborne androgens. During breeding, male sticklebacks (Gasterosteus aculeatus) manufacture a glue protein, spiggin, in their kidneys that they use to build their nests. Spiggin production is under the control of androgens. Until now, however, it has only been possible to quantify its production by measurement of the height of kidney epithelial cells. In the present study, we report the development of an enzyme-linked immunosorbent assay (ELISA) for spiggin and demonstrate its application to the measurement of spiggin in the kidneys of female sticklebacks that have been exposed to androgens in water. Results from the ELISA procedure revealed a strong correlation with measurement of kidney epithelial cell height (r2 = 0.93). However, the ELISA was much quicker and had a considerably higher response range (100,000-fold vs fourfold). Clear, graded responses in spiggin production were obtained by exposing intact females to increasing concentrations of 17,-methyltestosterone and 5,-dihydrotestosterone over three-week test periods. The lowest effective concentrations for these two steroids were 100 ng/L and 3 ,g/L, respectively. Female sticklebacks that were exposed to pulp mill effluent also produced spiggin in their kidneys. Possession of an androgen-regulated protein by the female stickleback makes it a unique bioassay organism for detecting androgenic contamination in the aquatic environment. [source] Histological evaluation of the osteoinduction capability of human dentineINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2006M. E. L. Machado Abstract Aim, To assess whether human dentine has the potential to promote the development of calcified tissues when implanted in the muscle tissue of mice. Methodology, Root canals in extracted human teeth were instrumented to produce dentine fragments. The dentine fragments produced were divided into two. In group 1, fragments were demineralized and sterilized. In group 2, the fragments were not submitted to any additional treatment. The dentine fragments were then implanted in the muscle of mice. In group 3, the muscles were implanted with rehydrated lyophilized human bone powder. Animals were killed following test periods of 7, 15, 30, 60, 120 and 180 days, the fragments were removed together with adjacent muscle and examined under light microscopy to assess calcification. Results, Areas of calcification were observed in groups 1 and 3 after a period of 180 days. In group 2, the surrounding tissues displayed only chronic inflammatory infiltration. Conclusions, On the basis of the experimental model adopted in this study, fibroblast-rich connective tissue formed in groups 1 and 3, which could reflect an osteoinductive process. Further studies are suggested to identify which dentinal factors are capable of inducing the formation of a calcified matrix. [source] Smoking cessation advice provided in 53 Norwegian pharmaciesINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 4 2004Dr. Anne G. Granas Director of research Objective To investigate the quality of the smoking cessation advice on over-the-counter (OTC) nicotine replacement treatment (NRT) provided by community and hospital pharmacies in Norway and to assess any change in customer services and pharmaceutical smoking cessation advice after a change in legislation deregulating NRT from pharmacy-only to general sale. Method A mystery shopper made 106 visits to 53 pharmacies in Oslo, Norway. The first visit was when NRT was a pharmacy-only medicine and the second when it had become available from any outlet as a general sales product. The pharmacies were scored on 12 observation parameters regarding customer service and pharmaceutical advice (score 0,4, total possible score was 48). Key findings There was considerable inter- and intra-pharmacy variation in scores. The pharmacies' total score ranged from 3 to 45. On only 14.2% of the visits was the service categorised as ,Good'. There was no statistically significant difference in total score between the two test periods (P = 0.56), and hence no measurable difference in customer services and pharmaceutical advice as a result of increased competition after the switch to general sale. A scatter plot showed no relationship between the individual pharmacies' total score at the two visits. Conclusions Pharmacies' scores for the quality of their smoking cessation advice were generally low. There was no measurable change in pharmacies' customer service and pharmaceutical advice following the deregulation of NRT. There was little consistency in the total score between the first and the second visit to the same pharmacy. Improvement is needed in the smoking cessation advice provided by Norwegian pharmacies. [source] Dichloroacetate- and trichloroacetate-induced oxidative stress in the hepatic tissues of mice after long-term exposureJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2010Ezdihar A. Hassoun Abstract Dichoroacetate (DCA) and trichloroacetate (TCA) were found to be hepatotoxic and hepatocarcinogenic in rodents. To investigate the role of oxidative stress in the long-term hepatotoxicity of the compounds, groups of mice were administered 7.7, 77, 154 and 410,mg,kg,1 per day, of either DCA or TCA, by gavage, for 4 weeks (4-W) and 13 weeks (13-W), and superoxide anion (SA), lipid peroxidation (LP) and DNA-single strand breaks (SSBs) were determined in the hepatic tissues. Significant increases in all of the biomarkers were observed in response to the tested doses of both compounds in the two test periods, with significantly greater increases observed in the 13-W, as compared with the 4-W, period. Hepatomegaly was only observed with a DCA dose of 410,mg,kg,1 per day in the 13-W treatment period, and that was associated with significant declines in the biomarkers, when compared with the immediately lower dose. With the exception of LP production in the 13-W treatment period that was similarly induced by the two compounds, the DCA-induced increases in all of the biomarkers were significantly greater than those of TCA. Since those biomarkers were significantly induced by the compounds' doses that were shown to be carcinogenic but at earlier periods than those demonstrating hepatotoxicity/haptocarcinogencity, they can be considered as initial events that may lead to later production of those long-term effects. The results also suggest LP to be a more significant contributing mechanism than SA and DNA damage to the long-term hepatotoxicity of TCA. Copyright © 2010 John Wiley & Sons, Ltd. [source] Relative effectiveness of powered and manual toothbrushes in elderly patients with implant-supported mandibular overdenturesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2002A. Tawse-Smith Abstract Aim: The aim of this study was to compare the clinical effectiveness of a powered toothbrush (Braun Oral-B Plaque Remover 3-D) and a manual soft toothbrush (Oral-B Squish-grip brush) for the control of supragingival plaque and soft tissue inflammation around implants supporting mandibular overdentures. Material and methods: The study sample involved 40 edentulous subjects, aged 55,80 years, having 2 unsplinted mandibular implants supporting a complete removable overdenture opposed by a maxillary complete denture. In this single-blinded, randomised, cross-over clinical trial, two 6-week experimental phases were separated by a 2-week wash-out period. 2 weeks prior to each experimental phase (pre-entry visits), implant abutments were polished to remove all plaque and a standardised instruction in the use of the toothbrush was given. Modified plaque and bleeding indices were recorded at the start and end of each experimental period. Mean index scores at each phase were analysed using paired t -test, and the mean number of sites showing a change in plaque or mucositis were compared using the Mann-Whitney U -test. Combined data from 2 different implant systems were considered after controlling for implant type. Results: Only minor changes in plaque and bleeding scores were observed following the two test periods. There were no statistically significant differences between the manual and powered toothbrushes. Conclusion: Manual and powered brushes were found to be of comparable efficacy with regard to improvement in peri-implant bleeding and plaque indices. Zusammenfassung Zielsetzung: Untersuchung der klinischen Effektivität einer elektrischen Zahnbürste (Braun Oral-B Plaque Remover 3-D) im Vergleich zu einer weichen Handzahnbürste (Oral-B Squish-grip brush) zur Kontrolle supragingivaler Plaque und Weichgewebsentzündung an Implantaten, die Unterkiefer-Totalprothesen tragen. Material und Methoden: Das Untersuchungskollektiv bestand aus 40 zahnlosen Patienten im Alter zwischen 55 und 80 Jahren, die 2 unverblockte Unterkiefer-Implantate zur Unterstützung einer Totalprothese aufwiesen. Der Oberkiefer war jeweils mit einer total schleimhautgetragenen Prothese versorgt. In dieser einfach verblindeten, randomisierten klinischen Cross-over-Studie wurden 2 6-wöchige experimentelle Phasen von einer 2-wöchigen Auswaschperiode unterbrochen. 2 Wochen vor jeder experimentellen Phase wurden die supragingivalen Implantatflächen von sämtlicher Plaque gereinigt und die Patienten erhielten eine Instruktion im Gebrauch der Zahnbürsten. Modifizierte Plaque- und Blutungsindizes wurden zu Beginn und am Ende jeder experimentellen Phase erhoben. Die Mittelwerte für die Indizes wurden mittels des paarigen t -Tests und die Zahl der Stellen, die eine Veränderung in Plaque und Mucositis aufwiesen, wurden durch den Mann-Whitney U -Test verglichen. Die Daten für 2 Implantatsysteme wurden zusammengefasst, nachdem der Einfluss des Implantatsystems überprüft worden war. Ergebnisse: Es wurden nur geringe Veränderungen der Plaque- und Blutungsindizes am Ende beider Testphasen beobachtet. Ein statistisch signifikanter Unterschied zwischen elektrischer und Handzahnbürste konnte nicht gezeigt werden. Schlussfolgerungen: Hand- und elektrische Zahnbürsten erwiesen sich als gleich effektiv für die Verbesserung periimplantärer Plaque- und Blutungsindizes. Résumé But: Le but de cette étude était de comparer l'efficacité clinique d'une brosse à dent électrique (Plaque remover 3D de Braun Oral B) et une brosse souple manuelle (squish grip d'oral B) pour le contrôle de la plaque supra-gingivale et l'inflammation des tissus mous autour d'implants supportant des overdentures mandibulaires. Matériaux et méthodes: L'échantillon étudié comprenait 40 sujets édentés, âgés de 55 à 80 ans, ayant 2 implants mandibulaires non reliés supportant une overdenture amovible complète et une prothèse maxillaire antagoniste complète. Dans cet essai clinique croisé en aveugle simple, randomisée, 2 phases expérimentales de 6 semaines encadraient une période d'arrêt de 2 semaines. 2 semaines avant chaque phase expérimentale, (visite de pré-entrée), les piliers implantaires étaient polis afin d'éliminer toute la plaque et des instructions standardisées d'utilisation de la brosse étaient données. On notait les indices, de saignement et de plaque modifié, au début et à la fin de chaque période expérimentale. Les notes d'indices moyens à chaque phase étaient analysées par le test t apparié et le nombre moyen de sites présentant une modification de la plaque ou de la mucosite était comparé par le test U de Mann Whitney. Les données combinées des 2 systèmes implantaires étaient considérées après cotrôle pour chaque type d'implant Résultats: De minimes modifications des notes de plaque et de saignement étaient observées après les deux périodes de test. Il n'y avait pas de différences statistiques significatives entre les brosses manuelles et électriques. Conclusion: Les brosses manuelles et électriques ont une efficacité comparable du point de vue de l'amélioration des indices de saignement et de plaque peri-implantaires. [source] | |||||||||||||||||||