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1.
Artigo em Inglês | MEDLINE | ID: mdl-38591546

RESUMO

PURPOSE: The composition and properties of resin-based composite materials could affect tooth wear and lead to clinical problems. Therefore, the study objective was to characterize human tooth wear behavior against a bulk-fill restorative (BF) compared to a conventional resin composite (RC) and a CAD/CAM resin nano ceramic (RN). METHODS: Square-shaped specimens of each material were prepared and sub-divided according to the number of testing cycles (n=8): 100,000, 250,000, and 500,000 cycles. An occlusal wear test was performed using a chewing machine with 49 N, 2 Hz, in 37°C distilled water. Human premolar cusps were used as antagonists. Micro-CT and laser scanner were used to scan antagonists and specimens, respectively. Wear volume was assessed using a software and the wear pattern was examined with SEM. Softening in solvent analysis was performed by measuring the materials' Knoop microhardness (KHN) before and after immersion in ethanol. Wear volume data were analyzed with two-way ANOVA and Student-Neuman-Keuls test (α=0.05). RESULTS: For tooth and specimen wear volume, there was statistical significance for material and number of cycles, but not for the interaction between factors. BF resulted in less tooth (p=0.008) and specimen (p=0.030) wear than RN and RC, which were similar (p⟩0.05). Volume loss increased from 100,000 to 500,000 cycles. BF showed the lowest microhardness (KHN1); and %ΔKHN similar to RC, but greater than RN. CONCLUSION: BF induced less volume loss to the tooth than RC and RN, while presenting greater wear resistance. The tooth wear pattern and damage progression were mild for all materials. CLINICAL SIGNIFICANCE: Resin composites show favorable wear behavior, leading to low volume loss and mild structural damage of the tooth. Regular bulk-fill resin composite stands out for its efficient restorative technique, low wear susceptibility and reduced capacity to wear down the tooth.

2.
Braz J Biol ; 84: e279536, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597531

RESUMO

Planting with higher density in sugarcane is one of the practices used to overcome low productivity. However, this planting material is equivalent to 25% of the total cost of production, being one of the main expenses for cultivation. In this sense, the present work aims to evaluate the productivity and economic viability of sugarcane as a function of planting density. The experiment was carried out at Usina Monte Alegre in the municipality of Mamanguape, Paraíba, Brazil, from March 2021 to January 2022 with the variety RB92579. Seven planting density were studied: T1: 7 gems m-1, T2: 10 gems m-1, T3: 12 gems m-1, T4: 11 gems m-1, T5: 15 gems m-1, T6: 17 gems m-1, T7: 24 gems m-1, in randomized blocks with four replications. Growth, productivity and economic viability were evaluated. The highest productivity of cane and sugar, 77.69 ton ha-1 and 10.390 ton ha-1, respectively, was with planting density of 17 and 24 gems-1. While the minimum productivity of cane (61.313 ton ha-1) and sugar (7.924 ton ha-1) was recorded at sowing density of 7 and 11 gems-1. However, cultivation density with 7 and 10 gems m-1 were the ones that provided the highest profitability around 50%, followed by density of 12, 15 and 17 gems m-1 with an average of 45% profit and 11 and 24 gems m-1 with the lowest proportion of profit on average 38%. The cultivation with 17 gems m-1 of cane provides in cane-plant, variety RB92579, greater productivity with a profit rate of 45%, being the most suitable.


Assuntos
Saccharum , Açúcares , Brasil
3.
J Dent Res ; 98(4): 437-442, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30744472

RESUMO

Monolithic zirconia crowns have become very popular; their surface finish is considered a key factor for restoration longevity. While polishing has shown excellent results in vivo, the surface glass infiltration of zirconia may offer superior damage resistance and aesthetic advantages by using tooth-colored glasses. Thus, the purpose of this study is to evaluate the efficacy of polishing and glass infiltration on the wear behavior of monolithic zirconia crowns. The wear behavior of intact natural molar teeth was investigated as a reference. Zirconia crowns were divided into 3 groups: PolZ-sintered then polished; PolGZ-polished in the presintered state and then glass infiltrated and sintered; NoPolGZ-as machined, glass infiltrated and sintered. Crowns were adhesively bonded to a dentin-like abutment. Zirconia crowns and molar teeth ( n = 15) were subjected to contact-slide-liftoff cyclic loading (200 N, 1.25 million cycles) with a steatite sphere ( r = 3 mm) as an antagonist in water. Surface and subsurface damages were investigated with optical and scanning electron microscopies. Wear depth and volume loss were determined with micro-computed tomography. PolGZ and NoPolGZ crowns exhibited shallow wear scars, where material loss remained within the glass/zirconia layer with no visible cracks. Meanwhile, PolZ crowns presented no visible wear damage. Volume loss (mm3) in the steatite antagonist was as follows (mean ± SD): PolZ = 0.022 ± 0.007, PolGZ = 0.011 ± 0.004, and NoPolGZ = 0.014 ± 0.006. Molar teeth yielded no measurable wear on the antagonist, while the wear scar on the teeth was greater than that on zirconia crowns, ranging from 0.07 to 0.35 mm3. The combination of polishing and glass infiltration on the occlusal surface of monolithic zirconia crowns yielded reduced wear on both crown and antagonist.


Assuntos
Porcelana Dentária , Desgaste de Restauração Dentária , Coroas , Esmalte Dentário , Estética Dentária , Teste de Materiais , Propriedades de Superfície , Microtomografia por Raio-X , Zircônio
4.
Transbound Emerg Dis ; 65(1): e113-e120, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28758367

RESUMO

The ruminant pestiviral species BVDV-1, BVDV-2 and BDV, along with the putative species HoBi-like, may cause substantial economic losses in cattle, sheep and goats. Brazil's large size, variable biomes and wide range of ruminant animal production within different geographic regions suggest that the presence and prevalence of ruminant pestivirus may differ by regions within Brazil. This study investigated the genetic diversity of ruminant pestiviruses and determined the frequency of active infections within two states of the Northeast Region of Brazil, Maranhão and Rio Grande do Norte. Serum samples from 16,621 cattle and 2,672 small ruminants from 569 different herds residing in this region were tested by RT-PCR followed by DNA sequencing. Seventeen positive cattle were detected (0.1%) from fifteen different herds (2.64%). All isolates were classified as HoBi-like pestiviruses based on phylogenetic analysis. All small ruminant samples tested negative. The findings presented herein suggest that the Northeast Region of Brazil has a uniquely high prevalence of HoBi-like viruses. The increasing reports of HoBi-like viruses detected in cattle in the field suggest that natural infection with these viruses may be more widespread than previously thought. The identification of HoBi-like viruses as the most prevalent type of ruminant pestivirus circulating in the Northeast Region of Brazil indicates the need for both continued monitoring and determination of the extent of economic losses associated with HoBi-like virus infections. In addition, it must be taken into account in the choice of diagnostic tests and in vaccine formulations.


Assuntos
Doenças dos Bovinos/virologia , Vírus da Diarreia Viral Bovina/genética , Variação Genética , Infecções por Pestivirus/veterinária , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Vírus da Diarreia Viral Bovina Tipo 1/classificação , Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 1/isolamento & purificação , Vírus da Diarreia Viral Bovina Tipo 2/classificação , Vírus da Diarreia Viral Bovina Tipo 2/genética , Vírus da Diarreia Viral Bovina Tipo 2/isolamento & purificação , Vírus da Diarreia Viral Bovina/classificação , Vírus da Diarreia Viral Bovina/isolamento & purificação , Infecções por Pestivirus/epidemiologia , Infecções por Pestivirus/virologia , Filogenia , Prevalência , Ruminantes , Análise de Sequência de DNA/veterinária
5.
Genet Mol Res ; 16(2)2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-28653741

RESUMO

Water stress can affect the yield in tomato crops and, despite this, there are few types of research aiming to select tomato genotypes resistant to the water stress using physiological parameters. This experiment aimed to study the variables that are related to the gas exchanges and the efficiency in water use, in the selection of tomato genotypes tolerant to water stress. It was done in a greenhouse, measuring 7 x 21 m, in a randomized complete block design, with four replications (blocks), being five genotypes in the F2BC1 generation, which were previously obtained from an interspecific cross between Solanum pennellii versus S. lycopersicum and three check treatments, two susceptible [UFU-22 (pre-commercial line) and cultivar Santa Clara] and one resistant (S. pennellii). At the beginning of flowering, the plants were submitted to a water stress condition, through irrigation suspension. After that CO2 assimilation, internal CO2, stomatal conductance, transpiration, leaf temperature, instantaneous water use efficiency, intrinsic efficiency of water use, instantaneous carboxylation efficiency, chlorophyll a and b, and the potential leaf water (Ψf) were observed. Almost all variables that were analyzed, except CO2 assimilation and instantaneous carboxylation efficiency, demonstrated the superiority of the wild accession, S. pennellii, concerning the susceptible check treatments. The high photosynthetic rate and the low stomatal conductance and transpiration, presented by the UFU22/F2BC1#2 population, allowed a better water use efficiency. Because of that, these physiological characteristics are promising in the selection of tomato genotypes tolerant to water stress.


Assuntos
Cruzamentos Genéticos , Desidratação/genética , Genótipo , Solanum lycopersicum/fisiologia , Estresse Fisiológico/genética , Água , Produção Agrícola , Solanum lycopersicum/genética , Transpiração Vegetal/genética
6.
Int Endod J ; 50(8): 729-739, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27520405

RESUMO

AIM: To determine the prevalence of preoperative endodontic pain (PREP) and the incidence of postoperative endodontic pain (POEP), identifying the predictors of PREP and POEP in a southern Brazilian subpopulation, using clinical data from an electronic chart database (ECD). METHODOLOGY: This retrospective observational study included 563 consecutive individuals presenting for root canal treatment (RCT). Patients were treated by undergraduate and graduate students, following standard RCT protocols. Demographic, medical and dental variables were extracted from a pre-structured and standardized ECD. The main outcomes PREP and incident POEP were collected through a 0-10 numeric rating scale, dichotomized as none/mild (<4) or moderate/severe (≥4) pain. Predictive models calculating the prevalence ratios (PR) of PREP and the relative risks (RR) of incident POEP were carried out with Poisson regression analysis, estimating the relationship between clinical factors, PREP and incident POEP. RESULTS: Mean age at baseline was 49.2 ± 17.1 years, with 68.4% women. The prevalence and incidence of moderate/severe PREP and POEP were 44.4% and 3.8%, respectively. RCT intervention significantly reduced PREP (P < 0.001). Multivariate analysis revealed that group of teeth, location (mandibular teeth), pulpitis, necrotic pulp, preoperative swelling and periapical radiolucency were independently associated with moderate/severe PREP, whilst age ≥60 years and root canal retreatments were independent protective factors to PREP (P < 0.05). No demographic, medical or dental variables were associated with POEP, although molar teeth (RR = 4.23, 95%CI = 0.93-19.2, P = 0.056) had a borderline nonsignificant association. CONCLUSIONS: Moderate/severe PREP was independently associated with age, group of teeth, location, preoperative swelling, retreatments and pulp and periapical status. No demographic, medical or dental variable predicted moderate/severe POEP following RCT amongst this subpopulation.


Assuntos
Doenças da Polpa Dentária/fisiopatologia , Doenças da Polpa Dentária/cirurgia , Polpa Dentária/fisiopatologia , Dor Facial/etiologia , Dor Pós-Operatória/etiologia , Tratamento do Canal Radicular/efeitos adversos , Brasil/epidemiologia , Registros Eletrônicos de Saúde , Dor Facial/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/epidemiologia , Prevalência , Estudos Retrospectivos
7.
Dent Mater ; 32(12): e382-e388, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27707502

RESUMO

OBJECTIVE: This study investigated the influence of the cooling protocol on the mechanical behavior of Y-TZP veneered with porcelain with different compositions. The tested hypotheses were: (1) Y-TZP infrastructures veneered with porcelain containing leucite in its composition presents higher flexural strength (σ) and reliability (m), and (2) slow cooling protocol results in greater σ and m. METHODS: A total of 120 bilayer porcelain-Y-TZP bar-shaped specimens were prepared with the dimensions of 1.8mm (0.8mm Y-TZP±1.0mm porcelain)×4.0mm×16.0mm. Specimens were divided into four groups (n=30) according to the porcelain composition (containing or not leucite) and cooling protocol. Fast cooling was performed by opening the furnace chamber at sintering temperature. For the slow cooling, the chamber was maintained closed until it reached the room temperature. Specimens were tested in three-point bending with the porcelain surface under tension using a universal testing machine, in 37°C water, at 0.5mm/min crosshead speed. Data were analyzed by two-way ANOVA, Tukey post-hoc test (α=0.05) and Weibull. RESULTS: Y-TZP veneered with porcelains with different microstructural composition presented similar σ and m values (p=0.718). The cooling protocol had no influence on the σ and m values of the experimental groups (p=0.718). Cracking represented 95% of failures, whereas the initial flaw propagated from the porcelain surface towards the interface. SIGNIFICANCE: Y-TZP veneered with porcelain containing or not leucite present similar mechanical behavior and, at 1-mm thickness, is not sensitive to the cooling protocol.


Assuntos
Facetas Dentárias , Zircônio , Silicatos de Alumínio , Porcelana Dentária , Teste de Materiais , Reprodutibilidade dos Testes , Propriedades de Superfície
8.
Dent Mater ; 32(5): 624-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26897479

RESUMO

OBJECTIVES: To estimate the reliability and failure behavior of fixed partial dentures (FPDs) fabricated using the CAD-on technique. METHODS: FPDs (n=25) were fabricated using a CAD/CAM system: IPS e.max ZirCAD - Crystall./Connect and IPS e.max CAD (Ivoclar). The restoration type ("three-unit bridge") and design method ("multilayer") based on Biogenerics were used. Framework and porcelain structures were united using a fusion ceramic (Crystall./Connect, Ivoclar). Mechanical fatigue was tested in a servohydraulic load frame machine at a cyclic loading (frequency: 2Hz; load ratio: 0.1). Based on previous data from specimens tested in fast fracture, three different stress profiles were used. The lifetime data were analyzed using an inverse power law-Weibull cumulative damage model (ALTA PRO, Reliasoft). All failed specimens were examined under a field emission scanning electron microscope. RESULTS: Porcelain chipping was the predominant (60%) mode of failure for FPDs tested in fast fracture and connector failure was predominant (67%) under fatigue. For fast fracture data, the Weibull modulus (ß) of FPDs was 7.8 combining the two failure modes. When chipping and connector fracture data were analyzed separately, ß values were 7.9 and 2.9. For the step stress fatigue test, ß values were lower than estimated using fast fracture, being 1.6 for connector fracture and 1.3 for porcelain chipping. SIGNIFICANCE: The test method (fast fracture or fatigue) significantly influenced the reliability of FPDs fabricated using the CAD-on technique, but it did not influence their failure behavior.


Assuntos
Falha de Restauração Dentária , Prótese Parcial Fixa , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Reprodutibilidade dos Testes , Estresse Mecânico , Zircônio
9.
Braz J Biol ; 75(4 Suppl 1): S239-44, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26602350

RESUMO

Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.


Assuntos
Composição Corporal , Peixes-Gato/fisiologia , Impedância Elétrica , Animais , Aquicultura
10.
Braz. j. biol ; 75(4)Nov. 2015.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468345

RESUMO

Abstract Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.


Resumo A análise da impedância bioelétrica (BIA) é considerada uma importante ferramenta para avaliar a composição corporal de diferentes animais de uma maneira rápida, não-destrutiva e de baixo custo. A espécie Sul-americana Steindachneridion scriptum, popularmente conhecida como suruvi, foi selecionada para este estudo. Foi utilizado um protocolo para produzir peixes com distintas composições corporais, permitindo a validação da BIA para análise adequada da composição corporal do suruvi. Os peixes foram alimentados duas vezes ao dia com duas dietas diferentes: uma de baixo teor lipídico (8,90%) e outra de alto teor lipídico (18,68%). Essa diferença nas dietas possibilitou a produção de indivíduos com diferentes composições corporais. As leituras da BIA foram determinadas utilizando-se o equipamento Quantum X Bioelectrical Body Composition Analyzer. Duas leituras (dorsal e ventral) foram obtidas para cada peixe. Após as leituras, para cada peixe individualmente, a composição proximal dos peixes foi determinada. Todos os dados obtidos foram utilizados para estabelecer as equações de correlação entre as análises proximais e os valores da BIA. Fortes correlações foram encontradas para S. scriptum. As maiores correlações foram obtidas para as análises dorsais a seguir: umidade e resistência em série (R2 = 0,87); proteína e resistência em série (R2 = 0,87); cinzas e reactância em paralelo (R2 = 0,82). Pode-se concluir que o método BIA é eficiente em determinar a composição corporal do suruvi S. scriptum sem sacrificar o animal. No entanto, para expandir o uso desta nova tecnologia é necessário definir protocolos rigorosos para garantir estimativas precisas.

11.
Braz. j. biol ; 75(4,supl.1): 239-244, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768245

RESUMO

Abstract Bioelectrical impedance analysis (BIA) is regarded as an important tool for evaluating the body composition of different animals in a rapid, non-destructive, and low-cost manner. A South American fish species, Steindachneridion scriptum, known as suruvi, was selected for study in this investigation. A protocol to produce fish with different body composition was used to allow BIA to adequately predict the body composition of suruvi. The fish were fed twice each day with two different diets; a low lipid diet (8.90%), and a high lipid diet (18.68%). These dietary differences allowed suruvi specimens with different body compositions to be produced. The BIA readings were determined using a Quantum X Bioelectrical Body Composition Analyzer. Two readings (dorsal and ventral) were obtained for each fish. After BIA readings were obtained, the proximate composition of the fish bodies for each individual was determined. All of the study data were used to establish correlation equations between proximate analyses and BIA values. Strong correlations were found for S. scriptum. The highest correlations were obtained for the following pairs of quantities, using BIA data from dorsal readings: moisture and resistance in series (R2 = 0.87); protein and resistance in series (R2 = 0.87); and ash and reactance in parallel (R2 = 0.82). We conclude that BIA is an effective method in determining the body composition of S. scriptum without sacrificing the fish. However, to expand the use of this new technology it is important to define strict BIA protocols to guarantee accurate estimates.


Resumo A análise da impedância bioelétrica (BIA) é considerada uma importante ferramenta para avaliar a composição corporal de diferentes animais de uma maneira rápida, não-destrutiva e de baixo custo. A espécie Sul-americana Steindachneridion scriptum, popularmente conhecida como suruvi, foi selecionada para este estudo. Foi utilizado um protocolo para produzir peixes com distintas composições corporais, permitindo a validação da BIA para análise adequada da composição corporal do suruvi. Os peixes foram alimentados duas vezes ao dia com duas dietas diferentes: uma de baixo teor lipídico (8,90%) e outra de alto teor lipídico (18,68%). Essa diferença nas dietas possibilitou a produção de indivíduos com diferentes composições corporais. As leituras da BIA foram determinadas utilizando-se o equipamento Quantum X Bioelectrical Body Composition Analyzer. Duas leituras (dorsal e ventral) foram obtidas para cada peixe. Após as leituras, para cada peixe individualmente, a composição proximal dos peixes foi determinada. Todos os dados obtidos foram utilizados para estabelecer as equações de correlação entre as análises proximais e os valores da BIA. Fortes correlações foram encontradas para S. scriptum. As maiores correlações foram obtidas para as análises dorsais a seguir: umidade e resistência em série (R2 = 0,87); proteína e resistência em série (R2 = 0,87); cinzas e reactância em paralelo (R2 = 0,82). Pode-se concluir que o método BIA é eficiente em determinar a composição corporal do suruvi S. scriptum sem sacrificar o animal. No entanto, para expandir o uso desta nova tecnologia é necessário definir protocolos rigorosos para garantir estimativas precisas.


Assuntos
Animais , Composição Corporal , Peixes-Gato/fisiologia , Impedância Elétrica , Aquicultura
12.
Dent Mater ; 31(12): 1453-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26472742

RESUMO

OBJECTIVE: To evaluate the flexural strength, Weibull modulus, fracture toughness, and failure behavior of ceramic structures obtained by the CAD-on technique, testing the null hypothesis that trilayer structures show similar properties to monolithic structures. METHODS: Bar-shaped (1.8mm×4mm×16mm) monolithic specimens of zirconia (IPS e.max ZirCAD - Ivoclar Vivadent) and trilayer specimens of zirconia/fusion ceramic/lithium dissilicate (IPS e.max ZirCAD/IPS e.max CAD Crystall./Connect/IPS e.max CAD, Ivoclar Vivadent) were fabricated (n=30). Specimens were tested in flexure in 37°C deionized water using a universal testing machine at a crosshead speed of 0.5mm/min. Failure loads were recorded, and the flexural strength values were calculated. Fractography principles were used to examine the fracture surfaces under optical and scanning electron microscopy. Data were statistically analyzed using Student's t-test and Weibull statistics (α=0.05). RESULTS: Monolithic and trilayer specimens showed similar mean flexural strengths, characteristic strengths, and Weibull moduli. Trilayer structures showed greater mean critical flaw and fracture toughness values than monolithic specimens (p<0.001). Most critical flaws in the trilayer groups were located on the Y-TZP surface subjected to tension and propagated catastrophically. Trilayer structures showed no flaw deflection at the interface. SIGNIFICANCE: Considering the CAD-on technique, the trilayer structures showed greater fracture toughness than the monolithic zirconia specimens.


Assuntos
Cerâmica/química , Desenho Assistido por Computador , Porcelana Dentária/química , Zircônio/química , Análise do Estresse Dentário , Módulo de Elasticidade , Teste de Materiais , Microscopia Eletrônica de Varredura , Maleabilidade , Reprodutibilidade dos Testes , Estresse Mecânico , Propriedades de Superfície
13.
Prev Vet Med ; 110(2): 169-76, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23218657

RESUMO

Between 2007 and 2009, a cross-sectional survey was carried out in Maranhão State, Brazil to estimate the seroprevalence of and risk factors for bovine brucellosis. In total, 749 herds and 6779 cows greater than two years of age were blood sampled. At the time of sampling a questionnaire to collect details on possible risk factors for bovine brucellosis was administered to the participating herd manager. A logistic regression model was developed to quantify the association between herd demographic and management characteristics and the herd-level brucellosis status. Spatial analyses were carried out to identify areas of the state where the presence of brucellosis was unaccounted-for by the explanatory variables in the logistic regression model. The estimated herd-level prevalence of brucellosis in Maranhão was 11.4% (95% CI 9.2-14) and the individual animal-level prevalence was 2.5% (95% CI 1.7-3.6). Herds with more than 54 cows older than two years of age, herds that used rented pasture to feed cattle, and the presence of wetlands on the home farm increased the risk of a herd being brucellosis positive. Infected farms were identified throughout the state, particularly in the central region and on the northwestern border. Spatial analyses of the Pearson residuals from the logistic regression model identified an area in the center of the state where brucellosis risk was not well explained by the predictors included in the final logistic regression model. Targeted investigations should be carried out in this area to determine more precisely the reasons for the unexplained disease excess. This process might uncover previously unrecognized risk factors for brucellosis in Maranhão.


Assuntos
Brucella/isolamento & purificação , Brucelose Bovina/epidemiologia , Brucelose Bovina/microbiologia , Animais , Brasil/epidemiologia , Brucelose Bovina/sangue , Bovinos , Estudos Transversais , Feminino , Mapeamento Geográfico , Modelos Logísticos , Mercaptoetanol , Modelos Biológicos , Prevalência , Fatores de Risco , Rosa Bengala , Estudos Soroepidemiológicos , Inquéritos e Questionários
14.
Int Endod J ; 45(2): 198-208, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21978185

RESUMO

AIM: To present the case of a maxillary left lateral incisor with Oehlers' type III dens invaginatus in which cone beam computed tomography (CBCT) was used as an adjunctive resource in the diagnosis as well as in the planning and 2-year follow-up of the nonsurgical/surgical treatment. SUMMARY: The tooth had two root canals: a primary (main) canal with vital pulp that appeared to be closed apically and an invaginated canal that was necrotic, wide-open at the portal of exit and associated with a large chronic periapical lesion extending to the apex of the maxillary left central incisor. Radiographic tracking of a sinus tract in the labial gingiva of the affected tooth with a gutta-percha point revealed its origin to be the invagination. The CBCT scans revealed that the periapical radiolucency was significantly larger than seen radiographically as well as an increased thickness of the buccal cortical plate. Conventional root canal treatment of the primary canal was undertaken. As nonsurgical access to the invaginated canal was not possible, endodontic surgery was performed for curettage of the lesion, root-end cavity preparation using ultrasonic tips and root canal filling with white mineral trioxide aggregate (MTA). CBCT scanning after 17 months and clinical and radiographic follow-up after 24 months revealed complete periapical repair and absence of symptoms. KEY LEARNING POINTS: The combination of nonsurgical and surgical treatments produced periapical repair in a tooth with type III dens invaginatus with two root canals. CBCT may aid the diagnosis as well as the management plan and follow-up of teeth with this developmental anomaly.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dens in Dente/diagnóstico por imagem , Incisivo/anormalidades , Planejamento de Assistência ao Paciente , Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Criança , Dens in Dente/terapia , Fístula Dentária/diagnóstico por imagem , Fístula Dentária/terapia , Cavidade Pulpar/anormalidades , Cavidade Pulpar/diagnóstico por imagem , Necrose da Polpa Dentária/diagnóstico por imagem , Necrose da Polpa Dentária/terapia , Combinação de Medicamentos , Seguimentos , Humanos , Incisivo/diagnóstico por imagem , Masculino , Óxidos/uso terapêutico , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/terapia , Obturação Retrógrada/métodos , Materiais Restauradores do Canal Radicular/uso terapêutico , Preparo de Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Silicatos/uso terapêutico
15.
Arq. bras. med. vet. zootec ; 63(5): 1154-1159, out. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-605841

RESUMO

The Pneumocystis genus is comprised of pathogens dwelling in the lungs of terrestrial, aerial, and aquatic mammals. Occasionally they induce severe pneumonitis, particularly in hosts with severe impairment of the immune system and progressively may fill pulmonary alveolar cavities causing respiratory failure. Molecular genetic studies revealed that Pneumocystis gene sequences present a marked divergence with the host species concerned. In the present study, the genetic diversity of Pneumocystis obtained from lungs of swines was examined by analyzing mitochondrial large subunit (mtLSU) and small subunit (mtSSU) rRNA sequences. The samples were obtained from two slaughterhouses located in two Brazilian states. Phylogenetic analysis demonstrated that genetic groupings within Pneumocystis organisms were in accordance with those of the corresponding hosts and that two clusters were formed. In conclusion, these data show that there are genetically distinct porcine Pneumocystis genotypes with at least two separate clusters in Brazil.


O gênero Pneumocystis compreende patógenos que residem em pulmões de animais terrestres, aéreos e aquáticos. Pode ocasionar uma grave pneumonia, particularmente em hospedeiros com o sistema imunológico seriamente comprometido, o que ocorre por meio de uma progressiva disseminação nas cavidades alveolares, causando insuficiência respiratória. Estudos genéticos, baseados em métodos moleculares, revelaram que as sequências dos genes de Pneumocystis apresentam marcante divergência de acordo com a espécie de hospedeiro. Neste estudo, a diversidade genética das amostras obtidas a partir de pulmões de suínos, provenientes de dois abatedouros localizados em dois estados brasileiros, foi examinada por análise das sequencias dos nucleotídeos dos produtos de PCR dos genes mtLSU e mtSSU do rRNA do Pneumocystis. O resultado confirma a tendência registrada em pesquisas com amostras de outros animais e permite concluir que existem, pelo menos, dois grupos filogenéticos distintos de Pneumocystis de suínos no Brasil.


Assuntos
Animais , Variação Genética , Infecções por Pneumocystis/veterinária , Suínos/virologia , Interações Hospedeiro-Patógeno/imunologia , Nucleotídeos/análise , Pulmão/fisiopatologia
16.
Psychooncology ; 20(11): 1242-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20818599

RESUMO

OBJECTIVE: Anxiety disorders have been shown to undermine the quality of life of cancer patients. Unfortunately, medical professionals often neglect to screen for anxiety in their patients. The aim of the present study was to describe the prevalence of anxiety in patients awaiting diagnostic procedures in an oncology center waiting room, and to investigate possible relationships between anxiety and demographic and clinical variables. METHODS: A cross-sectional study was performed with 398 patients who completed a self-administered questionnaire containing the Hospital Anxiety and Depression Scale (HADS) and the State-Trait Anxiety Inventory (STAI). RESULTS: Results of the HADS indicated that 38% of participants had anxiety, while data from the STAI showed that 46% had either high state or trait anxiety. The most frequently cited source of anxiety was concern over test results. Age, gender, employment status, and education level were correlated with anxiety. CONCLUSIONS: The prevalence of anxiety is high among patients awaiting diagnostic procedures. Patients in the waiting room should be routinely screened for anxiety. Careful assessment and treatment of anxiety are important components in the care of patients with cancer.


Assuntos
Ansiedade/epidemiologia , Neoplasias/psicologia , Ansiedade/etiologia , Ansiedade/psicologia , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Inventário de Personalidade , Prevalência , Escalas de Graduação Psiquiátrica , Fatores Socioeconômicos , Inquéritos e Questionários
17.
Artigo em Inglês | MEDLINE | ID: mdl-20847581

RESUMO

OBJECTIVES: To evaluate p63 expression in laryngeal squamous cell carcinoma and its prognostic significance. METHODS: p63 expression was examined by immunohistochemistry and scored in 127 patients with laryngeal squamous cell carcinomas. RESULTS: Sixty-two cases had scored 3, sixty had scored 2, four had scored 1 and one case did not show any expression (48.8, 47.2, 3.1 and 0.8%, respectively). Overall survival was 73.9% at 24 months and 59.5% at 60 months. The disease-free survival was 77.2 and 75.1%, and the disease-specific survival was 79 and 67% at 24 and 60 months, respectively. Uni- and multivariate analysis identified that decreased immunoexpression of protein p63 was a statistically significant factor for the risk of recurrence and death by cancer. CONCLUSIONS: p63 expression was highly prevalent in laryngeal squamous cell carcinomas, and its underexpression was correlated with a worse prognosis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , Transativadores/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Laringectomia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Fatores de Transcrição
18.
Med Mycol ; 45(5): 395-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17654265

RESUMO

The genus Pneumocystis is composed of opportunistic fungi currently considered as specific pulmonary pathogens in humans and other mammals. In pigs, Pneumocystis pneumonia (PcP) could create significant economical losses due to its detrimental effects on growth, food conversion, and carcass/viscera condemnation. This study revealed that Pneumocystis organisms could be detected by Grocott's staining or immunohistochemistry in 36.9% of 564 slaughtered pigs from two geographic regions of Brazil. The prevalence of positive cases was 39.9% and 33.9% in pigs slaughtered in Rio Grande do Sul (RS) and Mato Grosso (MT) states, respectively. Among the positive cases in RS, Pneumocystis organisms were observed in 41.9% of 33 histologically normal lungs, and in 58.0% of lungs presenting with histological lesions. In contrast, the prevalence in MT in normal and abnormal lungs was 36.3% and 63.5%, respectively. Major histopathological findings in lungs of infected animals were bronchointerstitial pneumonia (47.6%), suggestive of enzootic pneumonia, and interstitial pneumonia (37.9%), compatible with PcP. The results of this survey strengthened the interest of detecting fungal pathogens, in addition to other infectious agents, and evaluating their financial impact on Brazilian pig industry. Preventive and/or therapeutic strategies should be developed in order to minimize the incidence of respiratory fungal infections in pigs and associated economic losses.


Assuntos
Pulmão/microbiologia , Pneumocystis/classificação , Pneumocystis/isolamento & purificação , Pneumonia por Pneumocystis/veterinária , Doenças dos Suínos/epidemiologia , Matadouros , Animais , Brasil/epidemiologia , Pneumonia por Pneumocystis/epidemiologia , Pneumonia por Pneumocystis/microbiologia , Prevalência , Suínos , Doenças dos Suínos/microbiologia
19.
Arq Gastroenterol ; 36(2): 72-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10511885

RESUMO

Colonoscopy is employed in prevention, diagnosis, follow-up and treatment of colorectal diseases. The technological advancement of colonoscopes and supplementary equipment, has broadened indications for colonoscopy. However, since it is an invasive method with potential complications and hazards it should be performed by specialists capable of preventing, recognizing and treating them. The authors report their personal experience with 1,234 colonoscopies. The most frequent indications were changes in bowel habits and rectal bleeding in 35.1% and 30.5% cases respectively. The patients were given 10% mannitol for bowel cleansing and inadequate bowel cleansing in only 15 (1.2%) so that the colonoscopy could not be completed. The overall incidence of perforation was 0.16%. Three hundred and one polypectomies were performed and two cases (0.75%) of bleeding were noted.


Assuntos
Colonoscopia , Enteropatias/diagnóstico , Adolescente , Adulto , Idoso , Criança , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Arq Gastroenterol ; 36(3): 133-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10751900

RESUMO

The authors present their experience with 924 colonoscopic polypectomies in 549 patients. Postpolypectomy bleeding was 0.36% without perforations. Complications associated with the procedure are analyzed; evaluating the risk, diagnosis and treatment based on a survey of the literature and personal experience.


Assuntos
Pólipos do Colo/cirurgia , Adolescente , Adulto , Idoso , Criança , Colonoscopia/métodos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Cirurgia Vídeoassistida
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