53 resultados para Method Evaluation


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BACKGROUND: Only about 15% of donor lungs are considered suitable for transplantation (LTx). Ex vivo lung perfusion (EVLP) has been developed as a method to reassess and repair damaged lungs. We report our experience with EVLP in non-acceptable donor lungs and evaluate its ability to recondition these lungs. METHODS: We studied lungs from 16 brain-dead donors rejected for LTx. After harvesting, the lungs were stored at 4 degrees C for 10 hours and subjected to normothermic EVLP with Steen Solution (Vitro life, Goteborg, Sweden) for 60 minutes. For functional evaluation, the following variables were assessed: partial pressure of arterial oxygen (Pao(2)), pulmonary vascular resistance (PVR), and lung compliance (LC). For histologic assessment, lung biopsy was done before harvest and after EVLP. Tissue samples were examined under light microscopy. To detect and quantify apoptosis, terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling assay was used. RESULTS: Thirteen lima donors were refused for having impaired lung function. The mean Pao(2) obtained in the organ donor at the referring hospital was 193.7 mm Hg and rose to 489 mm Hg after EVLP. During EVLP, the mean PVR was 652.5 dynes/sec/cm(5) and the mean LC was 48 ml/cm H2O. There was no significant difference between the mean Lung Injury Score before harvest and after EVLP. There was a trend toward a reduction in the median number of apoptotic cells after EVLP. CONCLUSIONS: EVLP improved lung function (oxygenation capacity) of organs considered unsuitable for transplantation. Lung tissue structure did not deteriorate even after 1 hour of normothermic perfusion. J Heart Lung Transplant 2012;31:305-9 (C) 2012 International Society for Heart and Lung Transplantation. All rights reserved.

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The objective of this study was to evaluate the effects of adding alkalis on the fermentative pattern, aerobic stability and nutritive value of the sugarcane silage. A completely randomized design with 6 additives in two concentrations (1 or 2%), plus a control group, totalizing 13 treatments [(6x2)+1] with four replications, was used. The additives were sodium hydroxide (NaOH), limestone (CaCO3), urea (CO(NH2)(2)), sodium bicarbonate (NaHCO3), quicklime (CaO) and hydrated lime (Ca(OH)(2)). The material was ensiled in 52 laboratory silos using plastic buckets with 12 L of capacity. Silos were opened 60 days after ensiling, when organic acids concentration, aerobic stability and chemical composition were determined. The Relative Biological Efficiency (RBE) was calculated by the slope ratio method, using the data obtained from ratio between desirable and undesirable silage products, according to the equation: D/U ratio = [lactic/(ethanol + acetic + butyric)]. All additives affected dry matter, crude protein, acid detergent fiber, neutral detergent fiber contents and buffering capacity. Except for urea and quicklime, all additives increased the in vitro dry matter digestibility. In general, these additives altered the fermentative pattern of sugarcane silage, inhibiting alcoholic fermentation and improving lactic acid production. The additive that showed the best RBE in relation to sodium hydroxide (100%) was limestone (89.4%). The RBE values of urea, sodium bicarbonate and hydrated lime were 49.2%, 47.7% and 34.3%, respectively.

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Purpose: Few reports have evaluated cumulative survival rates of extraoral rehabilitation and peri-implant soft tissue reaction at long-term follow-up. The objective of this study was to evaluate implant and prosthesis survival rates and the soft tissue reactions around the extraoral implants used to support craniofacial prostheses. Materials and Methods: A retrospective study was performed of patients who received implants for craniofacial rehabilitation from 2003 to 2010. Two outcome variables were considered: implant and prosthetic success. The following predictor variables were recorded: gender, age, implant placement location, number and size of implants, irradiation status in the treated field, date of prosthesis delivery, soft tissue response, and date of last follow-up. A statistical model was used to estimate survival rates and associated confidence intervals. We randomly selected 1 implant per patient for analysis. Data were analyzed using the Kaplan-Meier method and log-rank test to compare survival curves. Results: A total of 150 titanium implants were placed in 56 patients. The 2-year overall implant survival rates were 94.1% for auricular implants, 90.9% for nasal implants, 100% for orbital implants, and 100% for complex midfacial implants (P = .585). The implant survival rates were 100% for implants placed in irradiated patients and 94.4% for those placed in nonirradiated patients (P = .324). The 2-year overall prosthesis survival rates were 100% for auricular implants, 90.0% for nasal implants, 92.3% for orbital implants, and 100% for complex midfacial implants (P = .363). The evaluation of the peri-implant soft tissue response showed that 15 patients (26.7%) had a grade 0 soft tissue reaction, 30 (53.5%) had grade 1, 6 (10.7%) had grade 2, and 5 (8.9%) had grade 3. Conclusions: From this study, it was concluded that craniofacial rehabilitation with extraoral implants is a safe, reliable, and predictable method to restore the patient's normal appearance. (C) 2012 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 70:1551-1557, 2012

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The electromagnetic interference between electronic systems or between their components influences the overall performance. It is important thus to model these interferences in order to optimize the position of the components of an electronic system. In this paper, a methodology to construct the equivalent model of magnetic field sources is proposed. It is based on the multipole expansion, and it represents the radiated emission of generic structures in a spherical reference frame. Experimental results for different kinds of sources are presented illustrating our method.

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This paper discusses the influence of fat type in the structure of ice cream, during its production by means of rheo-optical analysis. Fat plays an important part in the ice cream structure formation. It's responsible for the air stabilization, flavor release, texture and melting properties. The objective of this study was to use a rheological method to predict the fat network formation in ice cream with three types of fats (hydrogenated, low trans and palm fat). The three formulations were produced using the same methodology and ratio of ingredients. Rheo-optical measurements were taken before and after the ageing process, and the maximum compression force, overrun and melting profile were calculated in the finished product. The rheological analysis showed a better response from the ageing process from the hydrogenated fat, followed by the low trans fat. The formulation with palm fat showed greater differences between the three, where through the rheological tests a weaker destabilization of the fat globule membrane by the emulsifier was suggested. The overrun, texture measurements and meltdown profile has shown the distinction on the structure formation by the hydrogenated fat from the other fats.

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Purpose: This study aimed to investigate (1) the influence of complete denture quality and years of denture use on masticatory efficiency and (2) the relationship between complete denture quality and years of use. Materials and Methods: A cross-sectional study was conducted with 93 edentulous patients (mean age: 65.6 years) wearing both mandibular and maxillary dentures. Patients were classified into two categories according to years of denture use: <= 2 years and >= 5 years. Masticatory efficiency was evaluated via the colorimetric method with beads as the artificial test food. A reproducible method for objective evaluation of the technical quality of complete dentures was employed. The association between denture quality and years of denture use was analyzed using chi-square and Fisher exact tests. The results of masticatory efficiency testing were analyzed using two-way analysis of variance (with the Tukey post hoc test) in terms of years of denture use <= 2 years, >= 5 years) and denture quality (poor, average, good). Results: A significant relationship was found between denture quality and years of denture use (P < .05). Masticatory efficiency differed significantly (P < .05) between patients with <= 2 years of denture use (0.101 +/- 0.076 absorbance) and >= 5 years of use (0.068 +/- 0.076 absorbance). Masticatory efficiency was not influenced by denture quality. Conclusions: Complete denture quality and masticatory efficiency significantly decreased over time. However, complete denture quality did not influence masticatory efficiency. Int J Prosthodont 2012;25:625-630.

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Complexity in time series is an intriguing feature of living dynamical systems, with potential use for identification of system state. Although various methods have been proposed for measuring physiologic complexity, uncorrelated time series are often assigned high values of complexity, errouneously classifying them as a complex physiological signals. Here, we propose and discuss a method for complex system analysis based on generalized statistical formalism and surrogate time series. Sample entropy (SampEn) was rewritten inspired in Tsallis generalized entropy, as function of q parameter (qSampEn). qSDiff curves were calculated, which consist of differences between original and surrogate series qSampEn. We evaluated qSDiff for 125 real heart rate variability (HRV) dynamics, divided into groups of 70 healthy, 44 congestive heart failure (CHF), and 11 atrial fibrillation (AF) subjects, and for simulated series of stochastic and chaotic process. The evaluations showed that, for nonperiodic signals, qSDiff curves have a maximum point (qSDiff(max)) for q not equal 1. Values of q where the maximum point occurs and where qSDiff is zero were also evaluated. Only qSDiff(max) values were capable of distinguish HRV groups (p-values 5.10 x 10(-3); 1.11 x 10(-7), and 5.50 x 10(-7) for healthy vs. CHF, healthy vs. AF, and CHF vs. AF, respectively), consistently with the concept of physiologic complexity, and suggests a potential use for chaotic system analysis. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758815]

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Introduction: The ankle sprain is one of the most common injuries in athletes. Direct evaluation of the ligament laxity can be obtained through the objective measurement of extreme passive inversion and eversion movements, but there are few studies on the use of the evaluation of the passive resistive torque of the ankle to assess the capsule and ligaments resistance. Objective: The aim of this study was to compare the inversion and eversion passive torque in athletes with and without ankle sprains history. Method: 32 female basketball and volleyball athletes (16.06 +/- 0.8 years old; 67.63 +/- 8.17 kg; 177.8 +/- 6.47 cm) participated in this study. Their ankles were divided into two groups: control group (29), composed of symptom-free ankles, and ankle sprain group, composed of ankles which have suffered injury (29). The resistive torque at maximum passive ankle movement was measured by the isokinetic dynamometer and the muscular activity by electromyography system. The athletes performed 2 repetitions of inversion and eversion movement at 5, 10 and 20 degrees/s and the same protocol only at maximum inversion movement. Results: The resistive passive torque during the inversion and eversion was lower in the ankle sprain group. This group also showed lower torques at the maximum inversion movement. No differences were observed between inversion and eversion movement. Conclusions: Ankle sprain leads to lower passive torque, indicating reduction of the resistance of the lateral ankle ligaments and mechanical laxity.

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The assessment of adenoids by x-ray imaging has been the topic of heated debate, but few studies have looked into the reliability of most existing radiographic parameters. Objective: This study aims to verify the intra-examiner and inter-examiner reproducibility of the adenoid radiographic assessment methods. Materials and Methods: This is a cross-sectional case series study. Forty children of both genders aged between 4 and 14 were enrolled. They were selected based on complaints of nasal obstruction or mouth breathing and suspicion of pharyngeal tonsil hypertrophy. Cavum x-rays and orthodontic teleradiographs were assessed by two examiners in quantitative and categorical terms. Results: All quantitative parameters in both x-ray modes showed excellent intra and inter-examiner reproducibility. Relatively better performance was observed in categorical parameters used in cavum x-ray assessment by C-Kurien, C-Wang, C-Fujioka, and C-Elwany over C-Cohen and C-Ysunza. As for orthodontic teleradiograph grading systems, C-McNamara has been proven to be more reliable than C-Holmberg. Conclusion: Most instruments showed adequate reproducibility levels. However, more research is needed to properly determine the accuracy and viability of each method.

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Objective: To evaluate the Vickers hardness of different acrylic resins for denture bases with and without the addition of glass fibres. Background: It has been suggested that different polymerisation methods, as well as the addition of glass fibre (FV) might improve the hardness of acrylic. Materials and methods: Five types of acrylic resin were tested: Vipi Wave (VW), microwave polymerisation; Vipi Flash (VF), auto-polymerisation; Lucitone (LT), QC20 (QC) and Vipi Cril (VC), conventional heat-polymerisation, all with or without glass fibre reinforcement (GFR) and distributed into 10 groups (n = 12). Specimens were then submitted to Vickers hardness testing with a 25-g load for 30 s. All data were submitted to ANOVA and Tukey's HSD test. Results: A significant statistical difference was observed with regard to the polymerisation method and the GFR (p < 0.05). Without the GFR, the acrylic resin VC presented the highest hardness values, and VF and LT presented the lowest. In the presence of GFR, VC resin still presented the highest Vickers hardness values, and VF and QC presented the lowest. Conclusions: The acrylic resin VC and VW presented higher hardness values than VF and QC resins. Moreover, GFR increased the Vickers hardness of resins VW, VC and LT.

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Objective: to characterize the profiles of families in the area covered by a Primary Health Center and to identify those in a vulnerable situation. Method: this is an epidemiological, observational, cross-sectional and quantitative study. 320 home visits were made, defined by a random sample of the areas covered by the Urban Center 1 in the city of Sao Sebastiao, in Brazil's Federal District. A structured questionnaire was used for data collection, elaborated based on the Family Development Index (FDI). Results: there was a predominance of young families, women, and low levels of schooling. The FDI permitted the identification of families in situations of "high" and "very high" vulnerability. The most critical dimensions were: "access to knowledge" and "access to work". Conclusion: the study indicated the importance of greater investments in the areas of education, work and income, and highlighted the need for the use of a wider concept of vulnerability by the health services.

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A multiwall carbon nanotube/silicone rubber (MWCNT/SR) composite electrode has been used for the determination of hydrochlorothiazide (HCTZ) in pharmaceutical formulations by differential pulse voltammetry (DPV). The electro-oxidation process was evaluated by cyclic voltammetry, from which it was observed that HCTZ presents an irreversible oxidation peak at 0.82 V vs. saturated calomel electrode (SCE) in the potential range from 0.5 to 1.1 V, in Britton-Robinson buffer pH 7.0 at MWCNT/SR. HCTZ was determined by DPV using a MWCNT/SR 70% (MWCNT, m/m) composite electrode after the optimization of the experimental parameters. The linear range was from 5.0 to 70.0 mu mol L-1, with a limit of detection (LOD) of 2.6 mu mol L-1. The HCTZ was determined in pharmaceutical formulations using the proposed composite electrode and the results agreed with those from the official high performance liquid chromatography (HPLC) method within 95% confidence level, according to the t-Student test.

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The present study developed an experimental metronidazole-based gel and evaluated its efficacy for the adjuvant treatment of chronic periodontitis. Sixteen patients were randomly allocated into two groups of eight subjects according to the following proposed treatments: (1) scaling and root planing (active control) or (2) scaling and root planing and direct periodontal intrapocket application of 15% metronidazole-based gel in two sites (a parts per thousand yen5 mm in depth) (experimental group). Potential changes in the subgingival microbiota were assessed using a DNA Checkerboard method at three proposed times: baseline and following 7 or 30 days of drug administration. High-performance liquid chromatography (HPLC) monitored metronidazole concentrations in the crevicular fluid during treatment. The metronidazole experimental group presented lower bacterial counts than the control group at the three evaluated times (p < 0.01 for baseline, p < 0.001 for 7 or 30 days) when the target species were analyzed as a pool of bacteria. Samples revealed significantly lower counts 7 days after drug administration compared with baseline or after 30 days (p < 0.05). HPLC analysis detected gel 1 h after application. The metronidazole-based gel significantly decreased the total bacterial count at the three evaluated times. Periodontopathogenic species were not different after gel administration.

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Diclofenac sodium (DS) is a non-steroidal anti-inflammatory drug that is widely prescribed for the treatment of rheumatoid arthritis and post-surgery analgesia. The active pharmaceutical ingredient is the anhydrous form; however, it can also exist in hydrate form. In this context, knowing the properties of the solid state is important and relevant in the pharmaceutical area because they have a significant impact on the solubility, bioavailability, and chemical stability of the drugs. In the present study, data from XRPD, FTIR spectroscopy, and thermal analysis were used for the identification and characterization of DS forms (anhydrous and hydrate). An HPLC method was optimized to evaluate the plasma concentration of DS in rabbits. The optimized method exhibited good linearity over the range 0.1-60 mu g/mL with correlation coefficients of >0.9991. The mean recovery was 100%. Precision and accuracy were determined within acceptable limits. Finally, to compare the pharmacological properties of anhydrous and hydrate DS forms, we investigated their effects in the febrile response induced by lipopolysaccharide from E. coli in rabbits. The results show that the antipyretic effect of anhydrous and hydrate DS forms are similar.

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In this work, the reduction reaction of paraquat herbicide was used to obtain analytical signals using electrochemical techniques of differential pulse voltammetry, square wave voltammetry and multiple square wave voltammetry. Analytes were prepared with laboratory purified water and natural water samples (from Mogi-Guacu River, SP). The electrochemical techniques were applied to 1.0 mol L-1 Na2SO4 solutions, at pH 5.5, and containing different concentrations of paraquat, in the range of 1 to 10 mu mol L-1, using a gold ultramicroelectrode. 5 replicate experiments were conducted and in each the mean value for peak currents obtained -0.70 V vs. Ag/AgCl yielded excellent linear relationships with pesticide concentrations. The slope values for the calibration plots (method sensitivity) were 4.06 x 10(-3), 1.07 x 10(-2) and 2.95 x 10(-2) A mol(-1) L for purified water by differential pulse voltammetry, square wave voltammetry and multiple square wave voltammetry, respectively. For river water samples, the slope values were 2.60 x 10(-3), 1.06 x 10(-2) and 3.35 x 10(-2) A mol(-1) L, respectively, showing a small interference from the natural matrix components in paraquat determinations. The detection limits for paraquat determinations were calculated by two distinct methodologies, i.e., as proposed by IUPAC and a statistical method. The values obtained with multiple square waves voltammetry were 0.002 and 0.12 mu mol L-1, respectively, for pure water electrolytes. The detection limit from IUPAC recommendations, when inserted in the calibration curve equation, an analytical signal (oxidation current) is smaller than the one experimentally observed for the blank solution under the same experimental conditions. This is inconsistent with the definition of detection limit, thus the IUPAC methodology requires further discussion. The same conclusion can be drawn by the analyses of detection limits obtained with the other techniques studied.