Journals
2012 EN
Rastelli Alessandra N.S. · Jacomassi Denis P. · Faloni Ana Paula S.
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The purpose of this study was to compare the inorganic content and morphology of one nanofilled and one nanohybrid composite with one universal microhybrid composite. The Vickers hardness, degree of conversion and scanning electron microscope of the materials light‐cured using LED unit were also investigated. One nanofilled (Filtek™ Supreme XT), one nanohybrid (TPH® 3 ) and one universal microhybrid (Filtek™ Z‐250) composite resins at color A 2 were used in this study. The samples were made in a metallic mould (4 mm in diameter and 2 mm in thickness). Their filler weight content was measured by thermogravimetric analysis (TG). The morphology of the filler particles was determined using scanning electron microscope equipped with a field emission gun (SEM‐FEG). Vickers hardness and degree of conversion using FT‐IR spectroscopy were measured. Filtek™ Z‐250 (microhybrid) composite resin shows higher degree of conversion and hardness than those of Filtek™ Supreme XT (nanofilled) and TPH® 3 (nanohybrid) composites, respectively. The TPH 3 ® (nanohybrid) composite exhibits by far the lowest mechanical property. Nanofilled composite resins show mechanical properties at least as good as those of universal hybrids and could thus be used for the same clinical indications as well as for anterior restorations due to their high aesthetic properties. Microsc. Res. Tech. 75:758–765, 2012. © 2011 Wiley Periodicals, Inc
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2012 EN
Branco Érika · Cabral Rosa · Gomes Bruno Duarte
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Bone marrow is a source of stem cells for greater and easier access, which is widely studied as a provider of hematopoietic and mesenchymal cells for various purposes, mainly therapeutic by the advances in research involving cell therapy. The swine is an animal species commonly used in the pursuit of development of experimental models. Thus, this study aimed to standardize protocol for collection and separation of bone marrow in swines, since this species is widely used as experimental models for various diseases. Twelve animals were used, which underwent bone marrow puncture with access from the iliac crest and cell separation by density gradient followed by a viability test with an average of 98% of viable cells. Given our results, we can ensure the swine as an excellent model for obtaining and isolation of mononuclear cells from bone marrow, stimulating several studies addressing the field of cell therapy. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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2012 EN
Kuga Milton Carlos · Só Marcus Vinicius Reis · De Fariajúnior Norberto Batista
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The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol‐based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin‐based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1—95% ethanol, G2—70% ethanol, G3—70% isopropyl alcohol, or G4—eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at ×500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal–Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups ( P > 0.05), except between the eucalyptol and 70% ethanol groups ( P < 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
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2012 EN
Biguetti Claudia Cristina · Filho Emílio José Marquardt · de Andrade Holgado Leandro
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The aim of this study was to evaluate the healing process of intramembranous (IM) and endochondral (EC) bone grafts under low‐level laser therapy (LLLT). Male rabbits underwent onlay autogenous bone grafts (1 cm in diameter) retrieved from the calvaria and iliac crest and fixed on parietal bones, divided into four groups: Calvaria (C), Iliac (I), Calvaria + LLLT (C+L), and Iliac + LLLT (I+L). Animals from C+L and I+L Groups had their grafts exposed to LLLT (AlGaAs–808 nm, CW, 30 mW, 0.028 cm 2 average laser beam area), 15 s irradiation time (16 J/cm 2 per point–total of 64 J/cm 2 per session). After 7, 14, 30, and 60 days, grafts were retrieved and resorption pattern analyzed by means of morphometry and TRAP‐positive osteoclasts detection. Differences in the resorption levels of iliac grafts were observed, presenting 40% in I group against 8% in I+L grafts at the 14th day of evaluation ( P < 0.05). After 30 days, resorption was maintained at 41% in I group, whereas I+L presented 15% in the same period ( P = 0.0591). No significant differences were noted in the rates of calvaria grafts resorption in all periods. A significant higher number of osteoclasts on the grafts' surface was observed in C+L Group at day 30, in comparison with C group. In I+L Group, prevalence of osteoclasts was marked at day 7 ( P < 0.05) in comparison to I Group. In general, it was concluded that biomodulative effects of LLLT did not significantly affect healing and resorption processes of autogenous bone grafts from EC and IM origins. Microsc. Res. Tech. 75:1237–1244, 2012. © 2012 Wiley Periodicals, Inc.
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2012 EN
Sugita Reiji · Furuta Akemi · Horaguchi Jun
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Purpose: To visualize the movement of pancreatic juice noninvasively by using an unenhanced magnetic resonance (MR) imaging technique. Materials and Methods: Institutional review board approval and informed consent were obtained for this study. A flow‐out technique of time‐spatial labeling inversion pulse (SLIP) technique was applied using both nonselective and selective inversion pulses to label, or tag, pancreatic juice to move out of the region. Ten normal (eight men, two women; age range, 22–61 years; mean age, 35 years) and two pathologic conditions were examined on a commercially available 1.5 Tesla MR imager with quadrature‐detected phased‐array coils. All images were evaluated by two radiologists to assess depiction of the pancreatic juice movement or pancreatic juice reflux as compared to the pancreatic duct or the common bile duct on MRCP obtained before time‐SLIP examination. Results: The tagged pancreatic juice was satisfactory visualized after applying the pulse labeling. Noninvasive visualization of pancreatic juice movement, including normal pancreatic juice movement and reflux from the main pancreatic duct into the common bile duct, was possible by using the unenhanced time‐SLIP technique. Conclusion: Noninvasive visualization of pancreatic juice movement is possible by using the unenhanced MR imaging time‐SLIP technique. J. Magn. Reson. Imaging 2012;35:1019‐1124. © 2011 Wiley Periodicals, Inc.
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2012 EN
Kirsten Thiago B. · ChavesKirsten Gabriela P. · Chaible Lucas M.
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The aim of the present study was to evaluate the behavioral patterns associated with autism and the prevalence of these behaviors in males and females, to verify whether our model of lipopolysaccharide (LPS) administration represents an experimental model of autism. For this, we prenatally exposed Wistar rats to LPS (100 μg/kg, intraperitoneally, on gestational day 9.5), which mimics infection by gram‐negative bacteria. Furthermore, because the exact mechanisms by which autism develops are still unknown, we investigated the neurological mechanisms that might underlie the behavioral alterations that were observed. Because we previously had demonstrated that prenatal LPS decreases striatal dopamine (DA) and metabolite levels, the striatal dopaminergic system (tyrosine hydroxylase [TH] and DA receptors D1a and D2) and glial cells (astrocytes and microglia) were analyzed by using immunohistochemistry, immunoblotting, and real‐time PCR. Our results show that prenatal LPS exposure impaired communication (ultrasonic vocalizations) in male pups and learning and memory (T‐maze spontaneous alternation) in male adults, as well as inducing repetitive/restricted behavior, but did not change social interactions in either infancy (play behavior) or adulthood in females. Moreover, although the expression of DA receptors was unchanged, the experimental animals exhibited reduced striatal TH levels, indicating that reduced DA synthesis impaired the striatal dopaminergic system. The expression of glial cell markers was not increased, which suggests that prenatal LPS did not induce permanent neuroinflammation in the striatum. Together with our previous finding of social impairments in males, the present findings demonstrate that prenatal LPS induced autism‐like effects and also a hypoactivation of the dopaminergic system. © 2012 Wiley Periodicals, Inc.
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2012 EN
Ospitali Francesca · Chiavari Cristina · Martini Carla
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The characterization of corrosion patinas on bronzes is preliminarily connected to the determination of proper conservation strategies. Moreover, it also provides an essential contribution to the comprehension of the mechanisms of formation of patinas. Concerning the last aspect, several studies highlighted that bronze corrosion behaviour cannot be assimilated to that of pure copper. In particular, decuprification and relative enrichment of tin in the corrosion layers were observed. Tin therefore, together with its insoluble salts, plays an important role in the mechanism of formation of bronze patinas. Thus, the characterization of Sn‐based corrosion products becomes fundamental, although remaining quite problematic. This work reports several case studies where Sn‐based corrosion products grown in bronzes have been identified, thanks to the hyphenated system scanning electron microscopy–energy dispersive spectrometry–Raman structural and chemical analyser. Combining the main characteristics of these techniques, different Sn‐containing compounds, mainly crystalline and nano‐sized tin dioxides, were detected in bronze patinas exposed to different environments (to the atmosphere, in both natural and accelerated ageing conditions, and to the soil). The main issues regarding the interpretation of Raman spectra of these compounds are presented and discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Journals
2012 EN
Cai Zhiqiang · Zhang Shun
For elliptic interface problems with flux jumps, this article studies robust residual‐ and recovery‐based a posteriori error estimators for the conforming finite element approximation. The residual estimator is a natural extension of that developed in [Bernardi and Verfürth, Numer Math 85 (2000), 579–608; Petzoldt, Adv Comp Math 16 (2002), 47–75], and the recovery estimator is a nontrivial extension of our method developed in Cai and Zhang, SIAM J Numer Anal 47 (2009) 2132–2156. It is shown theoretically that reliability and efficiency bounds of these error estimators are independent of the jumps provided that the distribution of the coefficients is locally monotone. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28:476–491, 2012
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2012 EN
Cordelli Duccio Maria · Masetti Riccardo · Bernardi Bruno
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Background Posterior reversible encephalopathy syndrome (PRES) is a severe neurological complication after pediatric allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Seizures are a common manifestation of PRES. Status epilepticus (SE) is a potentially life‐threatening event rarely described in this condition. The aim of this study was to describe the clinical and electroencephalographic features of SE as a manifestation of PRES in children after allo‐HSCT. Procedure We retrospectively identified episodes of SE as a consequence of PRES out of 211 children who received allo‐HSCT in the period January 2000 to June 2008. Results PRES was diagnosed in 11 patients. We identified 12 episodes of SE associated to PRES in 10 patients. Nonconvulsive SE (NCSE) involving posterior regions of the brain (confirmed by EEG monitoring) was observed in four cases; convulsive SE (CSE) was observed in eight cases. Gaze deviation, oculoclonic movements, nystagmus, and altered mental status were the main clinical signs during NCSE and preceded CSE in 5/8 cases. Most patients needed intensive care management. A complete normalization of neurological examination and EEG pattern was observed in all patients after SE and withdrawal of causative agent. Follow‐up MRI showed complete resolution of brain edema in all patients. Conclusions Our experience shows that SE is more frequent than previously reported and is often the main manifestation of PRES after pediatric allo‐HSCT. Looking for suggestive clinical signs as well as routine use of EEG monitoring may allow prompt recognition of SE and therapy of both SE and PRES. Pediatr Blood Cancer 2012; 58: 785–790. © 2011 Wiley Periodicals, Inc.
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Journals
2012 EN
Melo Marcelo C. R. · Bernardi Rafael C. · Fernandes Tácio V. A.
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The folding process defines three‐dimensional protein structures from their amino acid chains. A protein's structure determines its activity and properties; thus knowing such conformation on an atomic level is essential for both basic and applied studies of protein function and dynamics. However, the acquisition of such structures by experimental methods is slow and expensive, and current computational methods mostly depend on previously known structures to determine new ones. Here we present a new software called GSAFold that applies the generalized simulated annealing (GSA) algorithm on ab initio protein structure prediction. The GSA is a stochastic search algorithm employed in energy minimization and used in global optimization problems, especially those that depend on long‐range interactions, such as gravity models and conformation optimization of small molecules. This new implementation applies, for the first time in ab initio protein structure prediction, an analytical inverse for the Visitation function of GSA. It also employs the broadly used NAMD Molecular Dynamics package to carry out energy calculations, allowing the user to select different force fields and parameterizations. Moreover, the software also allows the execution of several simulations simultaneously. Applications that depend on protein structures include rational drug design and structure‐based protein function prediction. Applying GSAFold in a test peptide, it was possible to predict the structure of mastoparan‐X to a root mean square deviation of 3.00 Å. Proteins 2012; © 2012 Wiley Periodicals, Inc.
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