936 resultados para short-2
Resumo:
The fatality risk caused by avalanches on road networks can be analysed using a long-term approach, resulting in a mean value of risk, and with emphasis on short-term fluctuations due to the temporal variability of both, the hazard potential and the damage potential. In this study, the approach for analysing the long-term fatality risk has been adapted by modelling the highly variable short-term risk. The emphasis was on the temporal variability of the damage potential and the related risk peaks. For defined hazard scenarios resulting from classified amounts of snow accumulation, the fatality risk was calculated by modelling the hazard potential and observing the traffic volume. The avalanche occurrence probability was calculated using a statistical relationship between new snow height and observed avalanche releases. The number of persons at risk was determined from the recorded traffic density. The method resulted in a value for the fatality risk within the observed time frame for the studied road segment. The long-term fatality risk due to snow avalanches as well as the short-term fatality risk was compared to the average fatality risk due to traffic accidents. The application of the method had shown that the long-term avalanche risk is lower than the fatality risk due to traffic accidents. The analyses of short-term avalanche-induced fatality risk provided risk peaks that were 50 times higher than the statistical accident risk. Apart from situations with high hazard level and high traffic density, risk peaks result from both, a high hazard level combined with a low traffic density and a high traffic density combined with a low hazard level. This provided evidence for the importance of the temporal variability of the damage potential for risk simulations on road networks. The assumed dependence of the risk calculation on the sum of precipitation within three days is a simplified model. Thus, further research is needed for an improved determination of the diurnal avalanche probability. Nevertheless, the presented approach may contribute as a conceptual step towards a risk-based decision-making in risk management.
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A bitopic ligand, 4-(3,5-dimethylpyrazol-4-yl)-1,2,4-triazole (Hpz-tr) (1), containing two different heterocyclic moieties was employed for the design of copper(II)–molybdate solids under hydrothermal conditions. In the multicomponent CuII/Hpz-tr/MoVI system, a diverse set of coordination hybrids, [Cu(Hpz-tr)2SO4]·3H2O (2), [Cu(Hpz-tr)Mo3O10] (3), [Cu4(OH)4(Hpz-tr)4Mo8O26]·6H2O (4), [Cu(Hpz-tr)2Mo4O13] (5), and [Mo2O6(Hpz-tr)]·H2O (6), was prepared and characterized. A systematic investigation of these systems in the form of a ternary crystallization diagram approach was utilized to show the influence of the molar ratios of starting reagents, the metal (CuII and MoVI) sources, the temperature, etc., on the reaction products outcome. Complexes 2–4 dominate throughout a wide crystallization range of the composition triangle, while the other two compounds 5 and 6 crystallize as minor phases in a narrow concentration range. In the crystal structures of 2–6, the organic ligand behaves as a short [N–N]-triazole linker between metal centers Cu···Cu in 2–4, Cu···Mo in 5, and Mo···Mo in 6, while the pyrazolyl function remains uncoordinated. This is the reason for the exceptional formation of low-dimensional coordination motifs: 1D for 2, 4, and 6 and 2D for 3 and 5. In all cases, the pyrazolyl group is involved in H bonding (H-donor/H-acceptor) and is responsible for π–π stacking, thus connecting the chain and layer structures in more complicated H-bonding architectures. These compounds possess moderate thermal stability up to 250–300 °C. The magnetic measurements were performed for 2–4, revealing in all three cases antiferromagnetic exchange interactions between neighboring CuII centers and long-range order with a net moment below Tc of 13 K for compound 4.
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BACKGROUND The discrepancy between the extensive impact of musculoskeletal complaints and the common deficiencies in musculoskeletal examination skills lead to increased emphasis on structured teaching and assessment. However, studies of single interventions are scarce and little is known about the time-dependent effect of assisted learning in addition to a standard curriculum. We therefore evaluated the immediate and long-term impact of a small group course on musculoskeletal examination skills. METHODS All 48 Year 4 medical students of a 6 year curriculum, attending their 8 week clerkship of internal medicine at one University department in Berne, participated in this controlled study. Twenty-seven students were assigned to the intervention of a 6×1 h practical course (4-7 students, interactive hands-on examination of real patients; systematic, detailed feedback to each student by teacher, peers and patients). Twenty-one students took part in the regular clerkship activities only and served as controls. In all students clinical skills (CS, 9 items) were assessed in an Objective Structured Clinical Examination (OSCE) station, including specific musculoskeletal examination skills (MSES, 7 items) and interpersonal skills (IPS, 2 items). Two raters assessed the skills on a 4-point Likert scale at the beginning (T0), the end (T1) and 4-12 months after (T2) the clerkship. Statistical analyses included Friedman test, Wilcoxon rank sum test and Mann-Whitney U test. RESULTS At T0 there were no significant differences between the intervention and control group. At T1 and T2 the control group showed no significant changes of CS, MSES and IPS compared to T0. In contrast, the intervention group significantly improved CS, MSES and IPS at T1 (p < 0.001). This enhancement was sustained for CS and MSES (p < 0.05), but not for IPS at T2. CONCLUSIONS Year 4 medical students were incapable of improving their musculoskeletal examination skills during regular clinical clerkship activities. However, an additional small group, interactive clinical skills course with feedback from various sources, improved these essential examination skills immediately after the teaching and several months later. We conclude that supplementary specific teaching activities are needed. Even a single, short-lasting targeted module can have a long lasting effect and is worth the additional effort.
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Placement of a single-tooth implant should be performed when a patient's facial growth has ceased. In this retrospective observational study, we evaluated if there was a difference in the timing of cessation of craniofacial growth in short, average, and long facial types. Based on the value of the angle between cranial base and mandibular plane (SN/MP angle), three groups comprising 48 subjects with short facial type (SF; SN/MP ≤28°), 77 with average facial type (AF; SN/MP ≥31.5° and ≤34.5°), and 44 with long facial type (LF; SN/MP ≥38°) were selected. Facial growth was assessed on lateral cephalograms taken at 15.4 years of age, and 2, 5, and 10 years later. Variables were considered to be stable when the difference between two successive measurements was less than 1 mm or 1°. We found no difference between facial types in the timing of cessation of facial growth. Depending on the variable, the mean age when variables became stable ranged from 18.0 years (Is-Pal in LF group) to 22.0 years (SN/MP in LF group). However, facial growth continued at the last follow-up in approximately 20% subjects. This study demonstrates that facial type is not associated with the timing of cessation of facial growth.
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BACKGROUND Implant-overdentures supported by rigid bars provide stability in the edentulous atrophic mandible. However, fractures of solder joints and matrices, and loosening of screws and matrices were observed with soldered gold bars (G-bars). Computer-aided designed/computer-assisted manufactured (CAD/CAM) titanium bars (Ti-bars) may reduce technical complications due to enhanced material quality. PURPOSE To compare prosthetic-technical maintenance service of mandibular implant-overdentures supported by CAD/CAM Ti-bar and soldered G-bar. MATERIALS AND METHODS Edentulous patients were consecutively admitted for implant-prosthodontic treatment with a maxillary complete denture and a mandibular implant-overdenture connected to a rigid G-bar or Ti-bar. Maintenance service and problems with the implant-retention device complex and the prosthesis were recorded during minimally 3-4 years. Annual peri-implant crestal bone level changes (ΔBIC) were radiographically assessed. RESULTS Data of 213 edentulous patients (mean age 68 ± 10 years), who had received a total of 477 tapered implants, were available. Ti-bar and G-bar comprised 101 and 112 patients with 231 and 246 implants, respectively. Ti-bar mostly exhibited distal bar extensions (96%) compared to 34% of G-bar (p < .001). Fracture rate of bars extensions (4.7% vs 14.8%, p < .001) and matrices (1% vs 13%, p < .001) was lower for Ti-bar. Matrices activation was required 2.4× less often in Ti-bar. ΔBIC remained stable for both groups. CONCLUSIONS Implant overdentures supported by soldered gold bars or milled CAD/CAM Ti-bars are a successful treatment modality but require regular maintenance service. These short-term observations support the hypothesis that CAD/CAM Ti-bars reduce technical complications. Fracture location indicated that the titanium thickness around the screw-access hole should be increased.
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OBJECTIVE To compare the precision of fit of long-span vs. short-span implant-supported screw-retained fixed dental prostheses (FDPs) made from computer-aided-design/computer-aided-manufactured (CAD/CAM) titanium and veneered with ceramic. The null hypothesis was that there is no difference in the vertical microgap between long-span and short-span FDPs. MATERIALS AND METHODS CAD/CAM titanium frameworks for an implant-supported maxillary FDP on implants with a flat platform were fabricated on one single master cast. Group A consisted of six 10-unit FDPs connected to six implants (FDI positions 15, 13, 11, 21, 23, 25) and group B of six 5-unit FDPs (three implants, FDI positions 21, 23, 25). The CAD/CAM system from Biodenta Swiss AG (Berneck, Switzerland) was used for digitizing (laser scanner) the master cast and anatomical CAD of each framework separately. The frameworks were milled (CAM) from a titanium grade V monobloc and veneered with porcelain. Median vertical distance between implant and FDP platforms from the non-tightened implants (one-screw test on implant 25) was calculated from mesial, buccal, and distal scanning electron microscope measurements. RESULTS All measurements showed values <40 μm. Total median vertical microgaps were 23 μm (range 2-38 μm) for group A and 7 μm (4-24 μm) for group B. The difference between the groups was statistically significant at implant 21 (P = 0.002; 97.5% CI -27.3 to -4.9) and insignificant at implant 23 (P = 0.093; -3.9 to 1.0). CONCLUSIONS CAD/CAM fabrication including laboratory scanning and porcelain firing was highly precise and reproducible for all long- and short-span FDPs. While all FDPs showed clinically acceptable values, the short-span FDPs were statistically more precise at the 5-unit span distance.
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BACKGROUND Multiple scores have been proposed to stratify bleeding risk, but their value to guide dual antiplatelet therapy duration has never been appraised. We compared the performance of the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the ACC/AHA Guidelines), ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy), and HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) scores in 1946 patients recruited in the Prolonging Dual Antiplatelet Treatment After Grading Stent-Induced Intimal Hyperplasia Study (PRODIGY) and assessed hemorrhagic and ischemic events in the 24- and 6-month dual antiplatelet therapy groups. METHODS AND RESULTS Bleeding score performance was assessed with a Cox regression model and C statistics. Discriminative and reclassification power was assessed with net reclassification improvement and integrated discrimination improvement. The C statistic was similar between the CRUSADE score (area under the curve 0.71) and ACUITY (area under the curve 0.68), and higher than HAS-BLED (area under the curve 0.63). CRUSADE, but not ACUITY, improved reclassification (net reclassification index 0.39, P=0.005) and discrimination (integrated discrimination improvement index 0.0083, P=0.021) of major bleeding compared with HAS-BLED. Major bleeding and transfusions were higher in the 24- versus 6-month dual antiplatelet therapy groups in patients with a CRUSADE score >40 (hazard ratio for bleeding 2.69, P=0.035; hazard ratio for transfusions 4.65, P=0.009) but not in those with CRUSADE score ≤40 (hazard ratio for bleeding 1.50, P=0.25; hazard ratio for transfusions 1.37, P=0.44), with positive interaction (Pint=0.05 and Pint=0.01, respectively). The number of patients with high CRUSADE scores needed to treat for harm for major bleeding and transfusion were 17 and 15, respectively, with 24-month rather than 6-month dual antiplatelet therapy; corresponding figures in the overall population were 67 and 71, respectively. CONCLUSIONS Our analysis suggests that the CRUSADE score predicts major bleeding similarly to ACUITY and better than HAS BLED in an all-comer population with percutaneous coronary intervention and potentially identifies patients at higher risk of hemorrhagic complications when treated with a long-term dual antiplatelet therapy regimen. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov. Unique identifier: NCT00611286.
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OBJECTIVE In Europe, growth hormone (GH) treatment for children born small for gestational age (SGA) can only be initiated after 4 years of age. However, younger age at treatment initiation is a predictor of favourable response. To assess the effect of GH treatment on early growth and cognitive functioning in very young (<30 months), short-stature children born SGA. DESIGN A 2-year, randomized controlled, multicentre study (NCT00627523; EGN study), in which patients received either GH treatment or no treatment for 24 months. PATIENTS Children aged 19-29 months diagnosed as SGA at birth, and for whom sufficient early growth data were available, were eligible. Patients were randomized (1:1) to GH treatment (Genotropin(®) , Pfizer Inc.) at a dose of 0·035 mg/kg/day by subcutaneous injection, or no treatment. MEASUREMENTS The primary objective was to assess the change from baseline in height standard deviation score (SDS) after 24 months of GH treatment. RESULTS Change from baseline in height SDS was significantly greater in the GH treatment vs control group at both month 12 (1·03 vs 0·14) and month 24 (1·63 vs 0·43; both P < 0·001). Growth velocity SDS was significantly higher in the GH treatment vs control group at 12 months (P < 0·001), but not at 24 months. There was no significant difference in mental or psychomotor development indices between the two groups. CONCLUSIONS GH treatment for 24 months in very young short-stature children born SGA resulted in a significant increase in height SDS compared with no treatment.
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BACKGROUND Recombinant bone morphogenetic protein two (rhBMP2) has been utilised for a variety of clinical applications in orthopaedic surgery and dental procedures. Despite its widespread use, concerns have been raised regarding its short half-life and transient bioactivity in vivo. Recent investigation aimed at developing rhBMP2 synthesized from a shorter polypeptide chain (108 amino acids) has been undertaken. METHODS The osteopromotive properties of BMP2 were investigated on cell behaviour. Five concentrations of rhBMP2_108 including 10, 50, 100, 200 and 500 ng/ml were compared to a commercially available rhBMP2 (100 ng/ml). Each of the working concentrations of rhBMP2_108 were investigated on MC3T3-E1 osteoblasts for their ability to induce osteoblast recruitment, proliferation and differentiation as assessed by alkaline phosphatase (ALP) staining, alizarin red staining, and real-time PCR for genes encoding ALP, osteocalcin (OCN), collagen-1 (COL-1) and Runx2. RESULTS The results demonstrate that all concentrations of rhBMP2_108 significantly improved cell recruitment and proliferation of osteoblasts at 5 days post seeding. Furthermore, rhBMP2_108 had the most pronounced effects on osteoblast differentiation. It was found that rhBMP2_108 had over a four fold significant increase in ALP activity at seven and 14 days post-seeding and the concentrations ranging from 50 to 200 ng/ml demonstrated the most pronounced effects. Analysis of real-time PCR for genes encoding ALP, OCN, COL-1 and Runx2 further confirmed dose-dependant increases at 14 days post-seeding. Furthermore, alizarin red staining demonstrated a concentration dependant increase in staining at 14 days. CONCLUSION The results from the present study demonstrate that this shorter polypeptide chain of rhBMP2_108 is equally as bioactive as commercially available rhBMP2 for the recruitment of progenitor cells by facilitating their differentiation towards the osteoblast lineage. Future in vivo study are necessary to investigate its bioactivity.
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5-aza-2'-deoxycytidine (DAC) is a cytidine analogue that strongly inhibits DNA methylation, and was recently approved for the treatment of myelodysplastic syndromes (MDS). To maximize clinical results with DAC, we investigated its use as an anti-cancer drug. We also investigated mechanisms of resistance to DAC in vitro in cancer cell lines and in vivo in MDS patients after relapse. We found DAC sensitized cells to the effect of 1-β-D-Arabinofuranosylcytosine (Ara-C). The combination of DAC and Ara-C or Ara-C following DAC showed additive or synergistic effects on cell death in four human leukemia cell lines in vitro, but antagonism in terms of global methylation. RIL gene activation and H3 lys-9 acetylation of short interspersed elements (Alu). One possible explanation is that hypomethylated cells are sensitized to cell killing by Ara-C. Turning to resistance, we found that the IC50 of DAC differed 1000 fold among and was correlated with the dose of DAC that induced peak hypomethylation of long interspersed nuclear elements (LINE) (r=0.94, P<0.001), but not with LINE methylation at baseline (r=0.05, P=0.97). Sensitivity to DAC did not significantly correlate with sensitivity to another hypomethylating agent 5-azacytidine (AZA) (r=0.44, P=0.11). The cell lines most resistant to DAC had low dCK, hENT1, and hENT2 transporters and high cytosine deaminase (CDA). In an HL60 leukemia cell line, resistance to DAC could be rapidly induced by drug exposure, and was related to a switch from monoallelic to biallelic mutation of dCK or a loss of wild type DCK allele. Furthermore, we showed that DAC induced DNA breaks evidenced by histone H2AX phosphorylation and increased homologous recombination rates 7-10 folds. Finally, we found there were no dCK mutations in MDS patients after relapse. Cytogenetics showed that three of the patients acquired new abnormalities at relapse. These data suggest that in vitro spontaneous and acquired resistance to DAC can be explained by insufficient incorporation of drug into DNA. In vivo resistance to DAC is likely due to methylation-independent pathways such as chromosome changes. The lack of cross resistance between DAC and AZA is of potential clinical relevance, as is the combination of DAC and Ara-C. ^
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This study evaluates the effect of a specially designed, physician-oriented handbook of antimicrobial use on the prescribing patterns of a group of fifty doctors at a university hospital. Data were evaluated over a peroid of one-and-one-half years, before and after the distribution of the handbook. For the purposes of this study, antimicrobial therapy was classified: (1) inappropriate if it violated one of a number of recognized principles of antimicrobial therapy, (2) appropriate if it agreed with specific recommendations or alternatives given in the distributed reference handbook, and (3) acceptable if it was neither inappropriate nor appropriate as defined by the handbook. An initial survey of antimicrobial prescribing patterns was made. Five months later the handbook was distributed and a two-week orientation program, consisting of the distribution and promotion of the problem-oriented, pocket-size handbook of appropriate antimicrobial therapy, was conducted. The handbook, which was developed by the authors and reviewed and approved by a panel of infectious disease specialists, presented guidelines for appropriate and efficacious usage of antimicrobial agents as most currently accepted in common clinical infections. Subsequent surveys were then conducted two weeks, three months, and six months after distribution of the handbook. A statistically significant difference (p < 0.01) in antimicrobial prescribing patterns was noted between the survey conducted two weeks after the introduction of the handbook and the other surveys. In this survey, while therapy classified inappropriate decreased from 44% to 28%, therapy appropriate as recommended increased from 31% to 53%. The findings of this study demonstrate that the introduction and promotion of the handbook decreases abuse and increases proper use of antimicrobial therapy, although the effect is sustainable for only a short duration--no longer than three months. These results indicate the need for a vigorous, updated program to achieve and maintain current appropriate antibotic therapy in clinical medicine. ^
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Entire issue (large pdf file) Articles include: Applying the Strengths Perspective to Increase Safety and Well-Being: Views from Families and Providers. Diane DePanfilis, Joshua Okundaye, Esta Glazer-Semmel, Lisa Kelly, and Joy Swanson Ernst Changing Tides and Changing Focus: Mapping the Challenges and Successes of One State's Implementation Of the Adoption and Safe Families Act of 1997. Scottye J. Cash, Scott D. Ryan, and Alison Glover Promising Practices to Engage Families and Support Family Preservation. Marianne Berry Implementing Intensive Family Preservation Services: A Case of lnfidelity. Raymond S. Kirk, Kellie Reed-Ashcrafi, and Peter J. Pecora Supporting Families through Short-Term Foster Care: An Essay Review. Anthony Maluccio Failed Child Welfare Policy: An Essay Review. Anthony Maluccio
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The pattern of expression of the pro$\alpha$2(I) collagen gene is highly tissue-specific in adult mice and shows its strongest expression in bones, tendons, and skin. Transgenic mice were generated harboring promoter fragments of the mouse pro$\alpha$2(I) collagen gene linked to the Escherichia coli $\beta$-galactosidase or firefly luciferase genes to examine the activity of these promoters during development. A region of the mouse pro$\alpha$2(I) collagen promoter between $-$2000 and +54 exhibited a pattern of $\beta$-galactosidase activity during embryonic development that corresponded to the expression pattern of the endogenous pro$\alpha$2(I) collagen gene as determined by in situ hybridization. A similar pattern of activity was also observed with much smaller promoter fragments containing either 500 or 350 bp of upstream sequence relative to the start of transcription. Embryonic regions expressing high levels of $\beta$-galactosidase activity included the valves of the developing heart, sclerotomes, meninges, limb buds, connective tissue fascia between muscle fibers, osteoblasts, tendon, periosteum, dermis, and peritoneal membranes. The pattern of $\beta$-galactosidase activity was similar to the extracellular immunohistochemical localization of transforming growth factor-$\beta$1 (TGF-$\beta$1). The $-$315 to $-$284 region of the pro$\alpha$2(I) collagen promoter was previously shown to mediate the stimulatory effects of TGF-$\beta$1 on the pro$\alpha$2(I) collagen promoter in DNA transfection experiments with cultured fibroblasts. A construct containing this sequence tandemly repeated 5$\sp\prime$ to both a very short $\alpha$2(I) collagen promoter ($-$40 to +54) and a heterologous minimal promoter showed preferential activity in tail and skin of 4-week old transgenic mice. The pattern of expression mimics that of the $-$350 to +54 pro$\alpha$2(I) collagen promoter linked to a luciferase reporter gene in transgenic mice. ^