25 resultados para Response Surface


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Introduction Reconstitution of peripheral blood (PB) B cells after therapeutic depletion with the chimeric anti-CD20 antibody rituximab (RTX) mimics lymphatic ontogeny. In this situation, the repletion kinetics and migratory properties of distinct developmental B-cell stages and their correlation to disease activity might facilitate our understanding of innate and adaptive B-cell functions in rheumatoid arthritis (RA). Methods Thirty-five 'RTX-naïve' RA patients with active arthritis were treated after failure of tumour necrosis factor blockade in an open-label study with two infusions of 1,000 mg RTX. Prednisone dose was tapered according to clinical improvement from a median of 10 mg at baseline to 5 mg at 9 and 12 months. Conventional disease-modifying antirheumatic drugs were kept stable. Subsets of CD19+ B cells were assessed by flow cytometry according to their IgD and CD27 surface expression. Their absolute number and relative frequency in PB were followed every 3 months and were determined in parallel in synovial tissue (n = 3) or synovial fluid (n = 3) in the case of florid arthritis. Results Six of 35 patients fulfilled the European League Against Rheumatism criteria for moderate clinical response, and 19 others for good clinical response. All PB B-cell fractions decreased significantly in number (P < 0.001) after the first infusion. Disease activity developed independently of the total B-cell number. B-cell repopulation was dominated in quantity by CD27-IgD+ 'naïve' B cells. The low number of CD27+IgD- class-switched memory B cells (MemB) in the blood, together with sustained reduction of rheumatoid factor serum concentrations, correlated with good clinical response. Class-switched MemB were found accumulated in flaring joints. Conclusions The present data support the hypothesis that control of adaptive immune processes involving germinal centre-derived, antigen, and T-cell-dependently matured B cells is essential for successful RTX treatment.

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The responses of carbon dioxide (CO2) and other climate variables to an emission pulse of CO2 into the atmosphere are often used to compute the Global Warming Potential (GWP) and Global Temperature change Potential (GTP), to characterize the response timescales of Earth System models, and to build reduced-form models. In this carbon cycle-climate model intercomparison project, which spans the full model hierarchy, we quantify responses to emission pulses of different magnitudes injected under different conditions. The CO2 response shows the known rapid decline in the first few decades followed by a millennium-scale tail. For a 100 Gt-C emission pulse added to a constant CO2 concentration of 389 ppm, 25 ± 9% is still found in the atmosphere after 1000 yr; the ocean has absorbed 59 ± 12% and the land the remainder (16 ± 14%). The response in global mean surface air temperature is an increase by 0.20 ± 0.12 °C within the first twenty years; thereafter and until year 1000, temperature decreases only slightly, whereas ocean heat content and sea level continue to rise. Our best estimate for the Absolute Global Warming Potential, given by the time-integrated response in CO2 at year 100 multiplied by its radiative efficiency, is 92.5 × 10−15 yr W m−2 per kg-CO2. This value very likely (5 to 95% confidence) lies within the range of (68 to 117) × 10−15 yr W m−2 per kg-CO2. Estimates for time-integrated response in CO2 published in the IPCC First, Second, and Fourth Assessment and our multi-model best estimate all agree within 15% during the first 100 yr. The integrated CO2 response, normalized by the pulse size, is lower for pre-industrial conditions, compared to present day, and lower for smaller pulses than larger pulses. In contrast, the response in temperature, sea level and ocean heat content is less sensitive to these choices. Although, choices in pulse size, background concentration, and model lead to uncertainties, the most important and subjective choice to determine AGWP of CO2 and GWP is the time horizon.

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In this study, we use IP and alkenone biomarker proxies to document the subdecadal variations of sea ice and sea surface temperature in the subpolar North Atlantic induced by the decadally paced explosive tropical volcanic eruptions of the second half of the thirteenth century. The short- and long-term evolutions of both variables were investigated by cross analysis with a simulation of the IPSL-CM5A LR model. Our results show short-term ocean cooling and sea ice expansion in response to each volcanic eruption. They also highlight that the long response time of the ocean leads to cumulative surface cooling and subsurface heat buildup due to sea ice capping. As volcanic forcing relaxes, the surface ocean rapidly warms, likely amplified by subsurface heat, and remains almost ice free for several decades

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Engineering nanoparticles (NPs) for immune modulation require a thorough understanding of their interaction(s) with cells. Gold NPs (AuNPs) were coated with polyethylene glycol (PEG), polyvinyl alcohol (PVA) or a mixture of both with either positive or negative surface charge to investigate uptake and cell response in monocyte-derived dendritic cells (MDDCs). Inductively coupled plasma optical emission spectrometry and transmission electron microscopy were used to confirm the presence of Au inside MDDCs. Cell viability, (pro-)inflammatory responses, MDDC phenotype, activation markers, antigen uptake and processing were analyzed. Cell death was only observed for PVA-NH2 AuNPs at the highest concentration. MDDCs internalize AuNPs, however, surface modification influenced uptake. Though limited uptake was observed for PEG-COOH AuNPs, a significant tumor necrosis factor-alpha release was induced. In contrast, (PEG+PVA)-NH2 and PVA-NH2 AuNPs were internalized to a higher extent and caused interleukin-1beta secretion. None of the AuNPs caused changes in MDDC phenotype, activation or immunological properties.

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This work presents a characterization of the surface wind climatology over the Iberian Peninsula (IP). For this objective, an unprecedented observational database has been developed. The database covers a period of 6years (2002–2007) and consists of hourly wind speed and wind direction data recorded at 514 automatic weather stations. Theoriginal observations underwent a quality control process to remove rough errors from the data set. In the first step, the annual and seasonal mean behaviour of the wind field are presented. This analysis shows the high spatial variability of the wind as a result of its interaction with the main orographic features of the IP. In order to simplify the characterization of the wind, a clustering procedure was applied to group the observational sites with similar temporal wind variability. A total of 20 regions are identified. These regions are strongly related to the main landforms of the IP. The wind behaviour of each region, characterized by the wind rose (WR), annual cycle (AC) and wind speed histogram, is explained as the response of each region to the main circulation types (CTs) affecting the IP. Results indicate that the seasonal variability of the synoptic scale is related with intra-annual variability and modulated by local features in the WRs variability. The wind speed distribution not always fit to a unimodal Weibull distribution consequence of interactions at different atmospheric scales. This work contributes to a deeper understanding of the temporal and spatial variability of surface winds. Taken together, the wind database created, the methodology used and the conclusion extracted are a benchmark for future works based on the wind behaviour.

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BACKGROUND A recombinant, replication-competent vesicular stomatitis virus-based vaccine expressing a surface glycoprotein of Zaire Ebolavirus (rVSV-ZEBOV) is a promising Ebola vaccine candidate. We report the results of an interim analysis of a trial of rVSV-ZEBOV in Guinea, west Africa. METHODS For this open-label, cluster-randomised ring vaccination trial, suspected cases of Ebola virus disease in Basse-Guinée (Guinea, west Africa) were independently ascertained by Ebola response teams as part of a national surveillance system. After laboratory confirmation of a new case, clusters of all contacts and contacts of contacts were defined and randomly allocated 1:1 to immediate vaccination or delayed (21 days later) vaccination with rVSV-ZEBOV (one dose of 2 × 10(7) plaque-forming units, administered intramuscularly in the deltoid muscle). Adults (age ≥18 years) who were not pregnant or breastfeeding were eligible for vaccination. Block randomisation was used, with randomly varying blocks, stratified by location (urban vs rural) and size of rings (≤20 vs >20 individuals). The study is open label and masking of participants and field teams to the time of vaccination is not possible, but Ebola response teams and laboratory workers were unaware of allocation to immediate or delayed vaccination. Taking into account the incubation period of the virus of about 10 days, the prespecified primary outcome was laboratory-confirmed Ebola virus disease with onset of symptoms at least 10 days after randomisation. The primary analysis was per protocol and compared the incidence of Ebola virus disease in eligible and vaccinated individuals in immediate vaccination clusters with the incidence in eligible individuals in delayed vaccination clusters. This trial is registered with the Pan African Clinical Trials Registry, number PACTR201503001057193. FINDINGS Between April 1, 2015, and July 20, 2015, 90 clusters, with a total population of 7651 people were included in the planned interim analysis. 48 of these clusters (4123 people) were randomly assigned to immediate vaccination with rVSV-ZEBOV, and 42 clusters (3528 people) were randomly assigned to delayed vaccination with rVSV-ZEBOV. In the immediate vaccination group, there were no cases of Ebola virus disease with symptom onset at least 10 days after randomisation, whereas in the delayed vaccination group there were 16 cases of Ebola virus disease from seven clusters, showing a vaccine efficacy of 100% (95% CI 74·7-100·0; p=0·0036). No new cases of Ebola virus disease were diagnosed in vaccinees from the immediate or delayed groups from 6 days post-vaccination. At the cluster level, with the inclusion of all eligible adults, vaccine effectiveness was 75·1% (95% CI -7·1 to 94·2; p=0·1791), and 76·3% (95% CI -15·5 to 95·1; p=0·3351) with the inclusion of everyone (eligible or not eligible for vaccination). 43 serious adverse events were reported; one serious adverse event was judged to be causally related to vaccination (a febrile episode in a vaccinated participant, which resolved without sequelae). Assessment of serious adverse events is ongoing. INTERPRETATION The results of this interim analysis indicate that rVSV-ZEBOV might be highly efficacious and safe in preventing Ebola virus disease, and is most likely effective at the population level when delivered during an Ebola virus disease outbreak via a ring vaccination strategy. FUNDING WHO, with support from the Wellcome Trust (UK); Médecins Sans Frontières; the Norwegian Ministry of Foreign Affairs through the Research Council of Norway; and the Canadian Government through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre, and Department of Foreign Affairs, Trade and Development.

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The use of hindcast climatic data is quite extended for multiple applications. However, this approach needs the support of a validation process to allow its drawbacks and, therefore, confidence levels to be assessed. In this work, the strategy relies on an hourly wind database resulting from a dynamical downscaling experiment, with a spatial resolution of 10 km, covering the Iberian Peninsula (IP), driven by the ERA40 reanalysis (1959–2001) extended by European Centre for Medium-Range Weather Forecast (ECMWF) analysis (2002–2007) and comprising two main steps. Initially, the skill of the simulation is evaluated comparing the quality-tested observational database (Lorente-Plazas et al., 2014) at local and regional scales. The results show that the model is able to portray the main features of the wind over the IP: annual cycles, wind roses, spatial and temporal variability, as well as the response to different circulation types. In addition, there is a significant added value of the simulation with respect to driving conditions, especially in regions with a complex orography. However, some problems are evident, the major drawback being the systematic overestimation of the wind speed, which is mainly attributed to a missrepresentation of frictional forces. The model skill is also lower along the Mediterranean coast and for the Pyrenees. In a second phase, the high spatio-temporal resolution of the pseudo-real wind database is used to explore the limitations of the observational database. It is shown that missing values do not affect the characterisation of the wind climate over the IP, while the length of the observational period (6 years) is sufficient for most regions, with only a few exceptions. The spatial distribution of the observational sampling schemes should be enhanced to improve the correct assessment of all IP wind regimes, particularly in some mountainous areas.

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PURPOSE Whole saliva comprises components of the salivary pellicle that spontaneously forms on surfaces of implants and teeth. However, there are no studies that functionally link the salivary pellicle with a possible change in gene expression. MATERIALS AND METHODS This study examined the genetic response of oral fibroblasts exposed to the salivary pellicle and whole saliva. Oral fibroblasts were seeded onto a salivary pellicle and the respective untreated surface. Oral fibroblasts were also exposed to freshly harvested sterile-filtered whole saliva. A genome-wide microarray of oral fibroblasts was performed, followed by gene ontology screening with DAVID functional annotation clustering, KEGG pathway analysis, and the STRING functional protein association network. RESULTS Exposure of oral fibroblasts to saliva caused 61 genes to be differentially expressed (P < .05). Gene ontology screening assigned the respective genes into 262 biologic processes, 3 cellular components, 13 molecular functions, and 7 pathways. Most remarkable was the enrichment in the inflammatory response. None of the genes regulated by whole saliva was significantly changed when cells were placed onto a salivary pellicle. CONCLUSION The salivary pellicle per se does not provoke a significant inflammatory response of oral fibroblasts in vitro, whereas sterile-filtered whole saliva does produce a strong inflammatory response.

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Insulin is an important regulator of renal salt and water excretion, and hyperinsulinemia has been implicated to play a role in hypertension. One of the target proteins of insulin action in the kidney is Na(+)/H(+) exchanger 3 (NHE3), a principal Na(+) transporter responsible for salt absorption in the mammalian proximal tubule. The molecular mechanisms involved in activation of NHE3 by insulin have not been studied so far. In opossum kidney (OK) cells, insulin increased Na(+)/H(+) exchange activity in a time- and concentration-dependent manner. This effect is due to activation of NHE3 as it persisted after pharmacological inhibition of NHE1 and NHE2. In the early phase of stimulation (2-12 h), NHE3 activity was increased without changes in NHE3 protein and mRNA. At 24 h, enhanced NHE3 activity was accompanied by an increase in total and cell surface NHE3 protein and NHE3 mRNA abundance. All the effects of insulin on NHE3 activity, protein, and mRNA were amplified in the presence of hydrocortisone. These results suggest that insulin stimulates renal tubular NHE3 activity via a biphasic mechanism involving posttranslational factors and an increase in NHE3 gene expression and the effects are dependent on the permissive action of hydrocortisone.

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Biodegradable magnesium plate/screw osteosynthesis systems were implanted on the frontal bone of adult miniature pigs. The chosen implant geometries were based on existing titanium systems used for the treatment of facial fractures. The aim of this study was to evaluate the in vivo degradation and tissue response of the magnesium alloy WE43 with and without a plasma electrolytic surface coating. Of 14 animals, 6 received magnesium implants with surface modification (coated), 6 without surface modification (uncoated), and 2 titanium implants. Radiological examination of the skull was performed at 1, 4, and 8 weeks post-implantation. After euthanasia at 12 and 24 weeks, X-ray, computed tomography, and microfocus computed tomography analyses and histological and histomorphological examinations of the bone/implant blocks were performed. The results showed a good tolerance of the plate/screw system without wound healing disturbance. In the radiological examination, gas pocket formation was found mainly around the uncoated plates 4 weeks after surgery. The micro-CT and histological analyses showed significantly lower corrosion rates and increased bone density and bone implant contact area around the coated screws compared to the uncoated screws at both endpoints. This study shows promising results for the further development of coated magnesium implants for the osteosynthesis of the facial skeleton.