25 research outputs found
Avaliação eletromiografica dos musculos masseter e temporal anterior de pacientes assintomaticos, sintomaticos e submetidos a tratamento das desordens temporomandibulares
Orientador: Wilkens Aurelio Buarque e SilvaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo desse trabalho foi comparar os valores da atividade eletromiográfica dos músculos masséter e temporal anterior com a mandíbula na posição de repouso, e em máxima intercuspidação habitual, e ainda determinar o coeficiente de simetria muscular em 44 mulheres na faixa etária entre 18 e 40 anos, com história negativa de bruxismo. As pacientes foram selecionadas de acordo com critérios pré-determinados e divididas por conveniência em três grupos: assintomáticas (G.CONT, n=14), com desordens temporomandibulares (G.DTM, n=16) e tratadas de desordens temporomandibulares (G.TRAT, n=14). As avaliações da atividade eletromiográfica foram realizadas com o sistema K6-1 (Myotronics-Noromed Inc. Tukwila, WA). Os resultados foram submetidos ao Teste não paramétrico de Mann-Whitney, com nível de significância de 5%. Durante a posição de repouso mandibular, a atividade do músculo masséter no G.CONT apresentou valores significativamente menores que os do G.DTM e do G.TRAT. No músculo temporal anterior, o G.DTM apresentou valores significativamente maiores que os do G.TRAT. Durante a máxima intercuspidação habitual no músculo masséter, os valores do G.CONT foram significativamente maiores que os do G.DTM, e no músculo temporal anterior, os valores do G.CONT foram significativamente maiores que os do G.DTM e do G.TRAT. A análise do coeficiente de simetria muscular em ambos os músculos, tanto na posição de repouso quanto na máxima intercuspidação habitual, não revelou diferenças entre os grupos. Pode-se concluir que: pacientes assintomáticos apresentam menor atividade eletromiográfica durante a posição de repouso e maior atividade durante a máxima intercuspidação habitual; pacientes com DTM apresentam maior atividade eletromiográfica durante a posição de repouso e menor atividade durante a máxima intercuspidação habitual; pacientes tratados de DTM apresentam valores da atividade eletromiográfica durante a posição de repouso e durante a máxima intercuspidação habitual, distintos dos indivíduos assintomáticos; pacientes assintomáticos, tratados e portadores de DTM apresentam coeficientes de simetria muscular semelhantes tanto na posição de repouso quanto na máxima intercuspidação habitualAbstract: This study was conducted to investigate the electromyographic activity values of the masseter and anterior temporalis muscles during rest and maximal intercuspal clenching, and the symmetry of the electromyographic activity of paired muscles, in 44 women, age range 18-40 years, with no history of bruxism. The patients were selected according pre-determined criteria, and were classified into three groups: asymptomatic (control group, n=14); TMD patients (TMD group, n=16); and TMD treated group (treated group, n=14). The electromyographic evaluations were performed using the K6-I/Emg Eight Channel Surface Electromyograph (Myotronics-Noromed Inc. Tukwila, WA). The data collected were compared using the Mann-Whitney U-test nonparametric analysis, and the results at rest showed EMG activity of masseter muscle in the control group significantly smaller than the TMD group and TMD-treated group; and EMG activity of anterior temporalis muscle at rest greater in the TMD compared to the TMD-treated group. The results of maximal clenching EMG activity of masseter muscle showed that the control group was significantly greater than the TMD group. The results at maximal intercuspal clenching showed EMG activity of masseter significantly greater in the control group than in the TMD group; and EMG activity of anterior temporalis muscle significantly greater in the control group than in the TMD group or TMD treated group. The symmetry of the electromyographic activity of paired muscles showed no differences among the groups nor at rest neither at maximal intercuspaI clenching. It was concluded that: asymptomatic subjects have the smallest electromyographic activity at rest and the greatest electromyographic activity at maximal intercuspal clenching; TMD patients have the greatest electromyographic activity at rest and the smallest electromyographic activity at maximal intercuspal clenching; TMD treated patients have different electromyographic pattems compared to asymptomatic subjects; The three groups have similar coefficient of symmetry in both masseter and anterior temporalis musclesDoutoradoProtese DentalDoutor em Clínica Odontológic
Estudo eletromiografico e eletrognatografico em pacientes com alterações funcionais do sistema estomatognatico, reabilitados com protese fixa
Orientador: Wilkens Aurelio Buarque e SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo desse trabalho foi analisar através da eletromiografia e eletrognatografia computadorizadas (K6-1 Oiagnostic System - Myo-tronics Research Inc. Seattle - WA), a atividade eletromiográfica em repouso e em máximo fechamento intercuspídico dos músculos masséter superficial e temporal anterior, e a amplitude dos movimentos mandibulares nos planos frontal e sagital, em pacientes com desordens temporomandibulares, idade média de 38 anos, reabilitados com prótese parcial fixa. Quatorze pacientes previamente tratados com aparelhos oclusais planos, foram classificados em grupo de origem muscular ou intrarticular, seguindo-se os critérios de LOBBEZOO-SCHOLTE et al. (1993), e reabilitados de acordo com WEINBERG (1983), WOOD (1988) e CLAYTON (1995). As avaliações eletromiográfica e eletrognatográfica foram padronizadas e realizadas antes, 120 e 180 dias após a cimentação das próteses. Os resultados foram submetidos ao Teste não paramétrico de Mann-Whitney, nível de significância de 5%, evidenciando não haver diferenças entre os grupos nos critérios máxima abertura vertical voluntária da mandíbula, desvios para a direita e esquerda durante a abertura da mandíbula, atividade eletromiográfica em repouso dos músculos masséter e temporal anterior, e atividade eletromiográfica em máximo fechamento intercuspídico do músculo temporal anterior, entretanto, uma maior atividade eletromiográfica em máximo fechamento intercuspídico no músculo masséter foi observada no grupo intrarticular. Os grupos muscular e intrarticular apresentaram atividade eletromiográfica simétrica entre os lados direito e esquerdo, tanto em repouso quanto em máximo fechamento intercuspídico nos músculos masséter e temporal anterior, contudo o grupo muscular apresentou a média da atividade eletromiográfica em repouso do músculo masséter maior no lado esquerdo. Os grupos de desordem muscular e intrarticular apresentaram desvio significante para esquerda durante a abertura mandibularAbstract: This study was conducted to investigate the range of mandibular movements in the frontal and sagittal planes, and the electromyographic activity (K6-1 Diagnostic System-Myo-tronics Research Inc., Seattle-WA) of the masseter and anterior temporalis muscles during rest and maximal intercuspal clenching in subjects with temporomandibular disorders. Fourteen patients, mean age of 38,7 years, were divided into two groups, one myogenous and other arthrogenous according to LOBBEZOO-SCHOLTE et al. (1993), and treated with flat occlusal splints. The both of them were rehabilitated with fixed partial prostheses according to WEINBERG (1983), WOOD (1988) e CLAYTON (1995). The electronic jaw tracking and the electromyographic evaluations were performed before, and 120 and 180 days after the cementation of the fixed prostheses. The data were compared using the Mann-Whitney U-test nonparametric analysis, and the results showed no differences between the groups in the criteria maximal vertical opening, left and right deviations, rest activity of the masseter and anterior temporalis muscles, and maximal intercuspal clenching activity of the anterior temporalis muscles, however, the arthrogenous group demonstrated greater maximal intercuspal clenching activity in the masseter muscle. Both the arthrogenous group and the myogenous group exhibited symmetric electromyographie activity between the left and right sides at rest and at maximal intercuspal elenching in the masseter and anterior temporalis muscles, though the myogenous group showed the mean rest activity greater in the left side. Both the arthrogenous group and the myogenous group displayed a significant left deviation during the maximal vertical opening of the jawMestradoProtese DentalMestre em Clínica Odontológic
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial
Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt
Effect of intrinsic pigmentation on the flexural strength of a microwave-cured acrylic resin
Efeito da pigmentação intrínseca na resistência à flexão de resina acrílica polimerizada por microondas
This study investigated the effect of intrinsic pigmentation on the transverse strength of a microwave-cured acrylic resin. Forty transverse strength specimens were fabricated according to ADA specification #12 and divided into 5 groups. No fibers were added to group I (GI, control group); acrylic stain (AS) was added to GII and GIII in concentrations of 0.5 and 1.5% w/w, respectively; acrylic fibers (AF) were added to groups GIV and GV in concentrations of 0.5 and 1.5% w/w, respectively. All specimens were irradiated in a microwave oven with a cycle of 3 min at 360 W, followed by 4 min resting, then 3 min at 810 W. Flasks were bench-cooled for 30 min at room temperature, followed by immersion in cold tap water for 30 min. After storage in distilled water at 37ºC for 48 h, all specimens were tested for flexural strength in a testing machine (EMIC-DL 500) at a crosshead speed of 0.5 cm/min. Mean and standard deviation (MPa) for the flexural strength test were: GI=86.0 ± 7.9; GII=86.0 ± 9.8; GIII=86.6 ± 7.7; GIV=84.9 ± 5.3; GV=84.9 ± 5.2. No statistical differences were detected among the groups (ANOVA, p>0.05). The addition of the acrylic fibers or the acrylic stain did not affect the transverse strength of the microwave-cured acrylic resin.Esse estudo avaliou o efeito da pigmentação intrínseca na resistência à flexão de uma resina acrílica polimerizada por microondas. Quarenta corpos de prova foram confeccionados (especificação no. 12 da ADA) e divididos em cinco grupos. O grupo I (GI) serviu como controle sem receber pigmentação. Pigmento acrílico foi adicionado aos grupos II (GII) e III (GIII) nas concentrações de 0,5 e 1,5%, respectivamente. Fibras acrílicas (FA) foram adicionadas à resina acrílica dos grupos IV (GIV) e V (GV) nas concentrações de 0,5 e 1,5% p/p, respectivamente. Todos os espécimes foram polimerizados em forno de microondas em um ciclo que consistia de 3 minutos a 360W, seguido por 4 minutos de pausa, e 3 minutos a 810W. As muflas foram resfriadas por 30 minutos em temperatura ambiente e imersas em água fria por 30 minutos. Após a armazenagem em água destilada por 48 h a 37ºC, todos os espécimes foram avaliados quanto à resistência a flexão (MPa), exibindo os seguintes valores (médias e desvios-padrão): GI=86,0 ± 7,9; GII=86,0 ± 9,8; GIII=86,6 ± 7,7; GIV=84,9 ± 5,3; GV=84,9 ± 5,2. Não foram detectadas diferenças estatísticas significantes entre os grupos (ANOVA, p>0,05). A adição de fibras acrílicas ou pigmento acrílico não afetou a resistência à flexão da resina acrílica polimerizada por microondas.20520