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101.
Karen Melina Trichês Jacy Simi Júnior João Batista Calixto Ricardo Machado Tiago Pereira Rosa Emmanuel João Nogueira Leal Silva Luiz Pascoal Vansan 《Microscopy research and technique》2013,76(12):1292-1296
The aim of this study was to evaluate the biocompatibility in rat subcutaneous connective tissue of a new zinc oxide endodontic sealer (Endomethasone N) compared to those provided by Endofill and Sealer 26. Polyethylene tubes containing the test materials were implanted into dorsal subcutaneous connective tissue of Wistar albino rats. After 7 and 42 days, the implants with the surrounding tissue were collected, fixed, and processed for histologic evaluation. Sections were evaluated for the presence of inflammatory cells (poly or monomorfonuclear), blood vessels, necrosis area, and thickness of fibrous capsule. Comparisons between groups and time‐periods were performed with Kruskal–Wallis and Mann–Whitney U non‐parametric tests for 5% significance level. No differences in the biocompatibility patterns among the materials for the 2 experimental periods were observed. Independently of the sealer, the tissue behavior showed a tendency to decrease the irritation effect over time. It can be concluded that all sealers are irritant, but its toxicity decreased with time. Endomethásone N showed biocompatible characteristics comparable with those provided by Endofill and Sealer 26. Microsc. Res. Tech. 76:1292–1296, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
102.
Kleiton de Morais Sousa Angelo A. Hafner Emerson Giovani Carati Hypolito José Kalinowski Jean Carlos Cardozo da Silva 《Measurement》2013
This works presents the simulation and validation of the thermal, electrical and mechanical models of a three-phase induction motor (TIM). Fiber Bragg grating (FBG) sensors are used to measure stator temperature and validate the thermal model. The knowledge of the relationship between losses and temperature variation in the TIM makes a simulation of the motor possible. To determine losses in the TIM an equivalent electrical circuit in arbitrary reference frame is used, which combines a traditional model with the more usual modeling of losses in the stator iron. The thermal study of the motor is performed using an equivalent thermal circuit formed by thermal capacitances and thermal conductivities that are separately considered for the stator and rotor. The losses calculated with the electrical and mechanical models are the input parameters for the thermal model. The simulation of the electrical model produces an error of approximately 4.2% when determining the Joule effect losses in the motor when compared to the experimentally obtained results. The simulation of the mechanical model presents an error of 0.2% for the losses due to friction and ventilation. The stator and rotor temperature, obtained with the thermal model, presented a high correlation with the measured values. The thermal model presents a maximum error of 0.75 °C when one compares them to the average experimental values of temperature in the stator during the temperature transient behavior. When the temperature in the stator reaches steady state, the experimental and simulated results converge to the same values. The use of FBGs to measure temperature in the machine allowed a thermal model to be developed, which also uses the mechanical losses of the machine and is the main contribution of this work. 相似文献
103.
104.
Camila Morais Melo Thiago Vidotto Luiz Paulo Chaves William Lautert-Dutra Rodolfo Borges dos Reis Jeremy Andrew Squire 《International journal of molecular sciences》2021,22(17)
Immunotherapy has improved patient survival in many types of cancer, but for prostate cancer, initial results with immunotherapy have been disappointing. Prostate cancer is considered an immunologically excluded or cold tumor, unable to generate an effective T-cell response against cancer cells. However, a small but significant percentage of patients do respond to immunotherapy, suggesting that some specific molecular subtypes of this tumor may have a better response to checkpoint inhibitors. Recent findings suggest that, in addition to their function as cancer genes, somatic mutations of PTEN, TP53, RB1, CDK12, and DNA repair, or specific activation of regulatory pathways, such as ETS or MYC, may also facilitate immune evasion of the host response against cancer. This review presents an update of recent discoveries about the role that the common somatic mutations can play in changing the tumor microenvironment and immune response against prostate cancer. We describe how detailed molecular genetic analyses of the tumor microenvironment of prostate cancer using mouse models and human tumors are providing new insights into the cell types and pathways mediating immune responses. These analyses are helping researchers to design drug combinations that are more likely to target the molecular and immunological pathways that underlie treatment failure. 相似文献
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106.
Santos MP França SA Santos JT Buzelle SL Bertolini GL Garófalo MA Kettelhut IC Frasson D Chaves VE Kawashita NH 《Lipids》2012,47(3):279-289
A low-protein, high-carbohydrate (LPHC) diet for 15 days increased the lipid content in the carcass and adipose tissues of
rats. The aim of this work was to investigate the mechanisms of this lipid increase in the retroperitoneal white adipose tissue
(RWAT) of these animals. The LPHC diet induced an approximately two- and tenfold increase in serum corticosterone and TNF-α,
respectively. The rate of de novo fatty acid (FA) synthesis in vivo was reduced (50%) in LPHC rats, and the lipoprotein lipase
activity increased (100%). In addition, glycerokinase activity increased (60%), and the phosphoenolpyruvate carboxykinase
content decreased (27%). Basal [U-14C]-glucose incorporation into glycerol-triacylglycerol did not differ between the groups; however, in the presence of insulin,
[U-14C]-glucose incorporation increased by 124% in adipocytes from only control rats. The reductions in IRS1 and AKT content as
well as AKT phosphorylation in the RWAT from LPHC rats and the absence of an insulin response suggest that these adipocytes
have reduced insulin sensitivity. The increase in NE turnover by 45% and the lack of a lipolytic response to NE in adipocytes
from LPHC rats imply catecholamine resistance. The data reveal that the increase in fat storage in the RWAT of LPHC rats results
from an increase in FA uptake from circulating lipoproteins and glycerol phosphorylation, which is accompanied by an impaired
lipolysis that is activated by NE. 相似文献
107.
Tiago Simões João Carvalho Ana Sousa Marco F.L. Lemos Maria M. Gil Rui Pedrosa Carla Tecelão 《Journal of food science》2013,78(5):C691-C695
Proximate composition (ash, moisture, total protein, and fat contents) and fatty acid profile of Balistes capriscus (grey triggerfish) were assessed over a 6‐months period (April to September, 2011) in animals captured along the coast of Peniche (Portugal). High protein (18.9% to 21.4%) and low lipid (0.5% to 0.8%) contents were determined. The highest lipid level was found in June‐captured animals. High proportions of n‐3 polyunsaturated fatty acids (n‐3 PUFA) were observed (53.87 ± 2.00%) together with substantial quantities of oleic acid (27.58 ± 1.09%) and palmitic acid (16.52 ± 0.93%). Docosahexaenoic acid accounted for 77% of the total PUFA and was 7 times more abundant than eicosapentaenoic acid, and the n‐3/n‐6 ratio was 7.2. Gender did not influence lipid levels and the fatty acid profile, but seasonal variations were observed for PUFA and monounsaturated fatty acid contents. Overall, the nutritional properties of this underexploited species may be comparable to those of other lean fish species with higher economic value. 相似文献
108.
André Rodrigues Tiago Camilo Jorge Sá Silva Fernando Boavida 《Journal of Network and Systems Management》2013,21(3):408-452
The availability of tools to diagnose Wireless Sensor Network (WSN) failures is a key success factor for this type of networks as already demonstrated by several long-running deployments. By nature, WSNs are resource-constrained, fragile, complex to analyse, and failure-prone. Naturally, with the growing number of installations, it is becoming fundamental to efficiently diagnose failures as soon as possible, in order to deal with the underlying causes. In accordance with this, from 2005 onwards, the offer of diagnostic tools has been increasing, as the other base technologies (e.g. networking, operating system, localisation, synchronisation) become reasonably stable. The purpose of this survey is to provide an overview of existing post-deployment WSN diagnostic tools, by briefly presenting their functionality, architecture and constraints, in order to enable a basic understating of each tool. The survey also includes a multi-dimensional comparative analysis of the various tools, based on a proposed classification scheme and evaluation criteria, as well as an identification of the main open research issues. Although the number of diagnostic tools is high and considerable work has been done in this area, we conclude that there are still several challenges concerning post-deployment WSN diagnostic tools, regarding scope, flexibility, generality, mobility and security. Moreover, there is a need for mature, native diagnostic-oriented functionality in WSN platforms and operating systems. 相似文献
109.
Effects of maturation and aging on the pressure‐bearing region of the plantaris longus tendon of the bullfrog (Lithobates catesbeianus) 下载免费PDF全文
Valdenilson José Zorel Jymenez De Morais Andrea Aparecida de Aro Laurecir Gomes Marcelo Augusto Marretto Esquisatto 《Microscopy research and technique》2014,77(10):797-805
The plantaris longus tendon (PLT) in bullfrog develops a fibrocartilage‐like tissue in the area that is functionally subject to compressive forces. The aim of this study was to analyze the modifications of the pressure‐bearing region in bullfrog PLT with different ages (7, 180, and 1,080 days after the end of metamorphosis) using histomorphometric, ultrastructural and biochemical methods. Weak basophilia and cells with a fibroblastic phenotype were observed in the compression region at 7 days of age. On the other hand, a large area of intense tissue basophilia associated with a chondroblast‐like cell population was noted at the other ages. Collagen fibers exhibited a three‐dimensional network‐like arrangement at all ages. The number of connective tissue cells increased between 7 and 180 days of age and was reduced in older animals. The 180‐day‐old animals presented a well‐developed pericellular matrix rich in proteoglycans. The mean diameter of collagen fibrils increased from 7 to 180 days and was the same at 1,080 days. Glycosaminoglycan content was higher in 7‐day‐old animals. A higher amount of hydroxyproline was observed at 180 and 1,080 days. The swelling test showed a significant increase of wet weight in 7‐day‐old animals. In conclusion, the alterations that occur in the pressure‐bearing of bullfrog PLT are the result of physiological alterations of the animal with the maturation and aging. Microsc. Res. Tech. 77:797–805, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
110.