927 resultados para Comparison between methods of analysis


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The fragile X syndrome (FXS), the most common cause of hereditary mental retardation, is caused by expansions of CGG repeats in the FMR1 gene. The gold-standard method to diagnose FXS is the Southern blot (SB). Because SB is laborious and costly, some adaptations in the polymerase chain reaction (PCR) method have been utilized for FXS screening. A previous PCR-based screening method for FXS identification utilizing small amounts of DNA was reported as simple and efficient. The aim of this study was to reproduce the mentioned PCR-based screening method for identification of expanded alleles of the FMR1 gene in Brazilian individuals and to investigate the efficiency of this method in comparison with SB. Utilizing the enzyme Expand Long Template PCR System, 78 individuals were investigated by that PCR-based screening method for FXS identification. Conclusive results were obtained for 75 samples. Considering all the allelic forms of FXS (normal [NL], premutation [PM], and full-mutation [FM]), the comparison of the PCR-based screening method with SB demonstrated 100% of accuracy, sensitivity, and specificity. However, when the PM and the FM were analyzed separately from each other, but together with the NL allele, the accuracy, sensitivity, and specificity decreased (to 42.9%-97.4%). We concluded that the PCR-based screening method was reproducible and capable of identifying all different FXS alleles, but because the differentiation between the PM and the FM alleles was not accurate, SB is still the gold-standard method for the molecular diagnosis of FXS.

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Aims: To compare the efficacy of histochemical and immunohistochemical methods in detecting forms of Sporothrix schenckii in tissue. Methods: Thirty five cutaneous biopsy specimens from 27 patients with sporotrichosis were stained by histochemical haemotoxylin and eosin, periodic acid Schiff, and Gomori's methenamine silver methods and an immunohistochemical (avidin-biotin complex immunoperoxidase) (ABC) technique associated with a newly produced rabbit polyclonal antibody anti-Sporothrix schenckii. Results: A total of 29 (83%) cases were positive by the ABC method used in association with anti-Sporothrix schenckii rabbit polyclonal antibodies. Histochemical methods, using silver staining, periodic acid Schiff, and conventional haematoxylin and eosin detected 37%, 23%, and 23% of forms of S schenckii, respectively. The ABC technique was significantly more reliable than periodic acid Schiff and silver staining techniques. Conclusions: It is concluded that immunostaining is an easy and rapid method which can efficiently increase the accuracy of the diagnosis of sporotrichosis in human tissue.

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Aim. The purpose of this study was to compare the anaerobic threshold speed (AT) obtained from fixed lactate blood concentrations (AT 4 mM and AT 3.5 mM), lactate minimum speed (LM) and critical speed (CS), determined from different distances in fifteen Brazilian national level swimmers (10 boys = 14.8 ± 0.6 years old and 5 girls = 14.6 ±0.8 year-old). Methods. The tests to determine the AT 4 mM, AT 3.5 mM, LM and CS were performed in a 25 m swimming pool and consisted of 7 or 8 evaluations separated by 24-48 h intervals. Data were submitted to analysis of variance (ANOVA) for repeated measures, followed by the post hoc Scheffé test and Pearson correlation coefficients. Significance was set at P<0.01. Results. There were no significant differences among the values for AT 4 mM and CS1 (1.34 ± 0.05 vs. 1.33 ± 0.05 m.s -1, respectively). However, AT 4 mM and CS1 were significantly higher than AT 3.5 mM (1.28 ± 0.04 m.s -1), LM (1.27 ± 0.05 m.s -1), CS2 (1.26 ± 0.06 m.s -1), CS3 (1.27 ± 0.06 m.s -1) and CS4 (1.25 ± 0.07 m.s -1). There were no significant differences among the values for AT 3.5 mM, LM, CS2, CS3 and CS4. Conclusion. The results obtained in this study suggest that the anaerobic threshold determined by a fixed lactate concentration of 3.5 mM, as well as the LM and the CS methods determined by different distances, seem to be the most appropriate indexes for the evaluation of aerobic capacity in adolescent swimmers.

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The wrist and hand region has been the most commonly used for estimating age and osseous development due to the great number of ossification centers. The aim was to determine which method, Tanner & Whitehouse's (TW3), Greulich & Pyle's (GP) or Eklof & Ringertz's, more closely relates to the chronological age in subjects with Down syndrome with chronological ages between 61 and 180 months, using wrist and hand radiographs. The sample consisted of 85 radiographs, 52 of males and 33 of females. Eklof & Ringertz's method was computerized (Radiomemory). Greulich & Pyle's atlas was used and compared with the wrist and hand radiographs. For the TW3 method, 13 ossification centers were evaluated; for each one of them, there are seven or eight development stages to which scores are assigned; these scores are then added and the results are transformed into osseous age values. No statistically significant differences were observed between the male and female genders for methods TW3 and GP, contrasting with the observed differences for the Eklof & Ringertz method. Correlation (r2) between osseous and chronological ages was 0.8262 for TW3 and 0.7965 for GP, while for the method of Eklof & Ringertz, it was 0.7656 for females and 0.8353 for males. The author concluded that the osseous age assessment method that better related to the chronological age was the TW3, followed by Greulich & Pyle's and Eklof & Ringertz's.

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Cogeneration may be defined as the simultaneous production of electric power and useful heat from the burning of a single fuel. This technique of combined heat and power production has been applied in both the industrial and tertiary sectors. It has been mainly used because of its overall efficiency, and the guarantee of electricity with a low level of environmental impact. The compact cogeneration systems using internal combustion engine as prime movers are thoroughly applied because of the good relationship among cost and benefit obtained in such devices. The cogeneration system of this study consists of an internal combustion engine using natural gas or biogas as fuel, combined with two heat exchangers and an absorption chiller utilising water-ammonia as working mixture. This work presents an energetic and economic comparison between natural gas and biogas as fuel used for the system proposed. The results are useful to identify the feasible applications for this system, such as residential sector in isolated areas, hotels, universities etc. (C) 2014 Elsevier Ltd. All rights reserved.

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The objective of this paper is compare the common traffic lights (CTL) to three different types of traffic lights with countdown displays (SCD) and assess their effects on road safety and capacity. This comparison is required because the results found in the literature are divergent among countries and cities, and one of the SCD analyzed in our study is different from the SCD used worldwide. An observational before-after study was conducted to evaluate the safety and capacity in a period of one year before and one year after the implementation of the SCD in three Brazilian cities. The results indicate that the SCD models 1 and 3 had around 35%±14% reduction in the total number of accidents; the model 2, does not have significant reduction. In order to perform the capacity analysis a framework for data collection and an adaptation for estimation of initial lost time in each phase were developed. Considering the capacity analysis there was a reduction around 11% in the lost time in SCD model 1, 7% in SCD model 2 and 3% in SCD model 3. However the implications of this on capacity are trifle due to a small increase in the average headways for all SCD models compare to CTL.

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OBJECTIVE: To compare the classical neurosurgical technique with a new simplified technique for prenatal repair of a myelomeningocelelike defect in sheep. METHODS: A myelomeningocele-like defect (laminectomy and dural excision) was created in the lumbar region on day 90 of gestation in 9 pregnant sheep. Correction technique was randomized. In Group 1 the defect was corrected using the classic neurosurgical technique of three-layer suture (dura mater, muscle and skin closure) performed by a neurosurgeon. In Group 2, a fetal medicine specialist used a biosynthetic cellulose patch to protect the spinal cord and only the skin was sutured above it. Near term (day 132 of gestation) fetuses were sacrificed for pathological analysis. RESULTS: There were two miscarriages and one maternal death. In total, six cases were available for pathological analysis, three in each group. In Group 1, there were adherence of the spinal cord to the scar (meningo-neural adhesion) and spinal cord architecture loss with posterior funiculus destruction and no visualization of grey matter. In Group 2, we observed in all cases formation of a neo-dura mater, separating the nervous tissue from adjacent muscles, and preserving the posterior funiculus and grey matter. CONCLUSION: The new simplified technique was better than the classic neurosurgical technique. It preserved the nervous tissue and prevented the adherence of the spinal cord to the scar. This suggests the current technique used for the correction of spina bifida in humans may need to be reassessed.

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Der Haupt-Lichtsammenkomplex II (LHCII) höherer Pflanzen ist das häufigsternMembranprotein der Welt und in die chloroplastidäre Thylakoidmembran integriert. DerrnLHCII kann als Modellsystem genutzt werden, um die Funktionsweise vonrnMembranproteinen besser zu verstehen, da 96 % seiner Struktur kristallografisch aufgelöstrnist und er in rekombinanter Form in vitro rückgefaltet werden kann. Hierbei entsteht einrnvoll funktionaler Protein-Pigment.Komplex, der nahezu identisch mit der in vivo Varianternist.rnElektronenparamagnetischen Resonanz (EPR) Spektroskopie ist eine hoch sensitive undrnideal geeignete Methode, um die Strukturdynamik von Proteinen zu untersuchen. Hierzurnist eine ortsspezifische Markierung mit Spinsonden notwendig, die kovalent an Cysteinernbinden. Möglich wird dies, indem sorgfältig ausgewählte Aminosäuren gegen Cysteinerngetauscht werden, ohne dass die Funktionsweise des LHCII beeinträchtigt wird.rnIm Rahmen dieser Arbeit wurden die Stabilität des verwendeten Spinmarkers und diernProbenqualität verbessert, indem alle Schritte der Probenpräparation untersucht wurden.rnMithilfe dieser Erkenntnisse konnte sowohl die Gefahr einer Proteinaggregation als auchrnein Verlust des EPR Signals deutlich vermindert werden. In Kombination mit derrngleichzeitigen Etablierung des Q-Band EPR können nun deutlich geringer konzentrierternProben zuverlässig vermessen werden. Darüber hinaus wurde eine reproduzierbarernMethode entwickelt, um heterogene Trimere herzustellen. Diese bestehen aus einemrndoppelt markierten Monomer und zwei unmarkierten Monomeren und erlauben es, diernkristallografisch unvollständig aufgelöste N-terminale Domäne im monomeren undrntrimeren Assemblierungsgrad zu untersuchen. Die Ergebnisse konnten einerseits diernVermutung bestätigen, dass diese Domäne im Vergleich zum starren Proteinkern sehrrnflexibel ist und andererseits, dass sie in Monomeren noch mobiler ist als in Trimeren.rnZudem wurde die lumenale Schleifenregion bei unterschiedlichen pH Werten undrnvariierender Pigmentzusammensetzung untersucht, da dieser Bereich sehr kontroversrndiskutiert wird. Die Messergebnisse offenbarten, dass diese Region starre und flexiblerernSektionen aufweist. Während der pH Wert keinen Einfluss auf die Konformation hatte,rnzeigte sich, dass die Abwesenheit von Neoxanthin zu einer Änderung der Konformationrnführt. Weiterführende Analysen der strukturellen Dynamik des LHCII in einerrnLipidmembran konnten hingegen nicht durchgeführt werden, da dies eine gerichteternInsertion des rückgefalteten Proteins in Liposomen erfordert, was trotz intensiverrnVersuche nicht zum Erfolg führte.

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With the outlook of improving seismic vulnerability assessment for the city of Bishkek (Kyrgyzstan), the global dynamic behaviour of four nine-storey r.c. large-panel buildings in elastic regime is studied. The four buildings were built during the Soviet era within a serial production system. Since they all belong to the same series, they have very similar geometries both in plan and in height. Firstly, ambient vibration measurements are performed in the four buildings. The data analysis composed of discrete Fourier transform, modal analysis (frequency domain decomposition) and deconvolution interferometry, yields the modal characteristics and an estimate of the linear impulse response function for the structures of the four buildings. Then, finite element models are set up for all four buildings and the results of the numerical modal analysis are compared with the experimental ones. The numerical models are finally calibrated considering the first three global modes and their results match the experimental ones with an error of less then 20%.

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The aim of our study was to evaluate the quality of histo- and cytomorphological features of PAXgene-fixed specimens and their suitability for histomorphological classification in comparison to standard formalin fixation. Fifteen colon cancer tissues were collected, divided into two mirrored samples and either formalin fixed (FFPE) or PAXgene fixed (PFPE) before paraffin embedding. HE- and PAS-stained sections were scanned and evaluated in a blinded, randomised ring trial by 20 pathologists from Europe and the USA using virtual microscopy. The pathologists evaluated histological grading, histological subtype, presence of adenoma, presence of lymphovascular invasion, quality of histomorphology and quality of nuclear features. Statistical analysis revealed that the reproducibility with regard to grading between both fixation methods was rather satisfactory (weighted kappa statistic (k w) = 0.73 (95 % confidence interval (CI), 0.41-0.94)), with a higher agreement between the reference evaluation and the PFPE samples (k w = 0.86 (95 % CI, 0.67-1.00)). Independent from preservation method, inter-observer reproducibility was not completely satisfactory (k w = 0.60). Histomorphological quality parameters were scored equal or better for PFPE than for FFPE samples. For example, overall quality and nuclear features, especially the detection of mitosis, were judged significantly better for PFPE cases. By contrast, significant retraction artefacts were observed more frequently in PFPE samples. In conclusion, our findings suggest that the PAXgene Tissue System leads to excellent preservation of histomorphology and nuclear features of colon cancer tissue and allows routine morphological diagnosis.

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OBJECTIVES To evaluate the diagnostic performance of seven non-invasive tests (NITs) of liver fibrosis and to assess fibrosis progression over time in HIV/HCV co-infected patients. METHODS Transient elastography (TE) and six blood tests were compared to histopathological fibrosis stage (METAVIR). Participants were followed over three years with NITs at yearly intervals. RESULTS Area under the receiver operating characteristic curve (AUROC) for significant fibrosis (> = F2) in 105 participants was highest for TE (0.85), followed by FIB-4 (0.77), ELF-Test (0.77), APRI (0.76), Fibrotest (0.75), hyaluronic acid (0.70), and Hepascore (0.68). AUROC for cirrhosis (F4) was 0.97 for TE followed by FIB-4 (0.91), APRI (0.89), Fibrotest (0.84), Hepascore (0.82), ELF-Test (0.82), and hyaluronic acid (0.79). A three year follow-up was completed by 87 participants, all on antiretroviral therapy and in 20 patients who completed HCV treatment (9 with sustained virologic response). TE, APRI and Fibrotest did not significantly change during follow-up. There was weak evidence for an increase of FIB-4 (mean increase: 0.22, p = 0.07). 42 participants had a second liver biopsy: Among 38 participants with F0-F3 at baseline, 10 were progessors (1-stage increase in fibrosis, 8 participants; 2-stage, 1; 3-stage, 1). Among progressors, mean increase in TE was 3.35 kPa, in APRI 0.36, and in FIB-4 0.75. Fibrotest results did not change over 3 years. CONCLUSION TE was the best NIT for liver fibrosis staging in HIV/HCV co-infected patients. APRI-Score, FIB-4 Index, Fibrotest, and ELF-Test were less reliable. Routinely available APRI and FIB-4 performed as good as more expensive tests. NITs did not change significantly during a follow-up of three years, suggesting slow liver disease progression in a majority of HIV/HCV co-infected persons on antiretroviral therapy.

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INTRODUCTION The aim of this study was to evaluate the concordance of 2- and 3-dimensional radiography and histopathology in the diagnosis of periapical lesions. METHODS Patients were consecutively enrolled in this study provided that preoperative periapical radiography (PR) and cone-beam computed tomographic imaging of the tooth to be treated with apical surgery were performed. The periapical lesional tissue was histologically analyzed by 2 blinded examiners. The final histologic diagnosis was compared with the radiographic assessments of 4 blinded observers. The initial study material included 62 teeth in the same number of patients. RESULTS Four lesions had to be excluded during processing, resulting in a final number of 58 evaluated cases (31 women and 27 men, mean age = 55 years). The final histologic diagnosis of the periapical lesions included 55 granulomas (94.8%) and 3 cysts (5.2%). Histologic analysis of the tissue samples from the apical lesions exhibited an almost perfect agreement between the 2 experienced investigators with an overall agreement of 94.83% (kappa = 0.8011). Radiographic assessment overestimated cysts by 28.4% (cone-beam computed tomographic imaging) and 20.7% (periapical radiography), respectively. Comparing the correlation of the radiographic diagnosis of 4 observers with the final histologic diagnosis, 2-dimensional (kappa = 0.104) and 3-dimensional imaging (kappa = 0.111) provided only minimum agreement. CONCLUSIONS To establish a final diagnosis of an apical radiolucency, the tissue specimen should be evaluated histologically and specified as a granuloma (with/without epithelium) or a cyst. Analysis of 2-dimensional and 3-dimensional radiographic images alike results only in a tentative diagnosis that should be confirmed with biopsy.

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The pattern of the births during the week has been reported by many studies. The births occurred in weekends are found consistently less then births occurred in weekdays. This study employed two statistical methods, two-way ANOVA and two-way Friedman's test to analyse the daily variations in amount of births of 222,735 births from 2005-2007 in Harris County, Texas. The two methods were compared on their assumptions, procedures and results. Both of the tests showed a significant result which indicated that the births through the week are not uniformly distributed. The result of multiple comparison demonstrated the births occurring on weekends were significantly different than the births occurring on weekdays with least amount on Sundays.^

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Finite element hp-adaptivity is a technology that allows for very accurate numerical solutions. When applied to open region problems such as radar cross section prediction or antenna analysis, a mesh truncation method needs to be used. This paper compares the following mesh truncation methods in the context of hp-adaptive methods: Infinite Elements, Perfectly Matched Layers and an iterative boundary element based methodology. These methods have been selected because they are exact at the continuous level (a desirable feature required by the extreme accuracy delivered by the hp-adaptive strategy) and they are easy to integrate with the logic of hp-adaptivity. The comparison is mainly based on the number of degrees of freedom needed for each method to achieve a given level of accuracy. Computational times are also included. Two-dimensional examples are used, but the conclusions directly extrapolated to the three dimensional case.