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Bacterial chemoreceptors control the activity of the associated CheA kinase in response to chemical gradients and, consequently, regulate the swimming behavior of the cell. However, such control is not direct but requires the participation of the essential coupling protein CheW, which is structurally homologous to the carboxy-terminal domain of the kinase. The actual role of this small coupling protein is somehow intriguing. It has been demonstrated that it is absolutely essential for chemoreceptor control of the kinase, in spite of the occurrence of direct contacts between chemoreceptors and CheA. In addition, CheW plays an essential role in the assembly of the large macromolecular arrays that combine chemoreceptors of different specificities, and it is therefore responsible for molecular interactions that provide such arrays with remarkable signaling properties. In this work, we analyze truncated CheW derivatives that are still able to control the kinase but have lost the ability to connect signaling units. We demonstrate that these two activities can work separately and speculate about the significance of the roles of these two different activities in the context of the chemoreceptor cluster.

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Objetivo: Objetivou-se avaliar o desempenho de próteses totais (PT) com dentes anatômicos e não anatômicos em pacientes idosos desdentados totais, quanto ao impacto na qualidade de vida relacionada à saúde bucal (OHQoL), satisfação, performance mastigatória (PM), necessidade de ajuste após a instalação das PTs e preferência do paciente quanto ao tipo oclusal. Materiais e métodos: Em um ensaio clínico randomizado do tipo crossover, 50 idosos desdentados totais foram divididos em duas sequências de tratamento: DA-DN (reabilitados inicialmente com dentes anatômicos e, após, 3 meses, com dentes não anatômicos) e DN-DA (reabilitados inicialmente com dentes não anatômicos e, após 3 meses, com dentes anatômicos). O OHQoL foi analisado através do OHIP-EDENT e um questionário de satisfação foi aplicado. A PM foi por análise granulométrica, após a mastigação de um alimento artificial. O alimento-teste triturado foi submetido a um sistema de tamises e o peso das partículas em cada peneira foi utilizado para determinar o tamanho mediano das partículas (X50). A quantidade de ajustes na base da prótese foi avaliada quantativamente. Para a análise dos dados, foram utilizados os testes não-paramétricos de Mann-Whitney e correlação de Spearman. Resultados: A amostra final foi composta por 34 idosos, com idade média de 69 anos. Não houve diferença entre usuários de prótese total com dentes anatômicos e não anatômicos, tanto para o OHIP-EDENT (p=0,674) e satisfação (0,725) como para a PM (p = 0,849) e nem com relação ao número de ajustes na base das próteses totais após a instalação (p=0,135). Conclusão: Dentes com superfícies oclusais planas, quando comparados a dentes anatômicos não mostraram-se vantajosos no que concerne ao impacto da saúde oral na qualidade de vida, a satisfação do usuário, a performance mastigatória, ao números de ajustes após a instalação da prótese e a preferência em relação ao tipo de superfície oclusal (AU).

Objective: The objective of this study was to remove pressure (PT) with anatomical and nonanatomical teeth in edentulous elderly patients, with impact on oral health related quality of life (OHQoL), satisfaction, masticatory performance (PM) the installation of hands and preference of the patient to the occlusal type. Materials and methods: In a crossover randomized clinical trial, 50 edentulous elderly patients were divided into two treatment stages: AD-ND (rehabilitated in the past with anatomical teeth and, after 3 months, with nonanatomical teeth) and DN-DA (initially rehabilitated with non-anatomical teeth and, after 3 months, with anatomical teeth). The OHQoL was analyzed through OHIP-EDENT and for satisfaction through a questionnaire. PM was evaluated by the granulometric analysis method, after mastication of an artificial food. The shredded test food was subjected to a sieve system and the weight of the particles in each sieve was used to determine the mean particle size (X 50). The amount of data at the base of the prosthesis was evaluated numerically. Data analysis, on the other hand, was not tested by Mann-Whitney and Spearman. Results: A final sample was made by 34 elderly, with a mean age of 69 years. OHIP-EDENT (p = 0.674) and satisfaction (p=0.725) as well as PM (p = 0.849), and for the number of total prosthesis care after installation (total dentures) with anatomical and non-anatomical teeth. p = 0.135). Conclusion: The occlusal alterations of the plane, when compared with the anatomical teeth, did not prove to be advantageous with respect to the impact of oral health on quality of life, user satisfaction, masticatory performance and conditioning graphics after the installation of prosthesis (AU).

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Accurate measurement of herbage intake rate is critical to advance knowledge of the ecology of grazing ruminants. This experiment tested the integration of behavioral and acoustic measurements of chewing and biting to estimate herbage dry matter intake (DMI) in dairy cows offered micro-swards of contrasting plant structure. Micro-swards constructed with plastic pots were offered to three lactating Holstein cows (608±24.9 kg of BW) in individual grazing sessions (n=48). Treatments were a factorial combination of two forage species (alfalfa and fescue) and two plant heights (tall=25±3.8 cm and short=12±1.9 cm) and were offered on a gradient of increasing herbage mass (10 to 30 pots) and number of bites (~10 to 40 bites). During each grazing session, sounds of biting and chewing were recorded with a wireless microphone placed on the cows' foreheads and a digital video camera to allow synchronized audio and video recordings. Dry matter intake rate was higher in tall alfalfa than in the other three treatments (32±1.6 v. 19±1.2 g/min). A high proportion of jaw movements in every grazing session (23 to 36%) were compound jaw movements (chew-bites) that appeared to be a key component of chewing and biting efficiency and of the ability of cows to regulate intake rate. Dry matter intake was accurately predicted based on easily observable behavioral and acoustic variables. Chewing sound energy measured as energy flux density (EFD) was linearly related to DMI, with 74% of EFD variation explained by DMI. Total chewing EFD, number of chew-bites and plant height (tall v. short) were the most important predictors of DMI. The best model explained 91% of the variation in DMI with a coefficient of variation of 17%. Ingestive sounds integrate valuable information to remotely monitor feeding behavior and predict DMI in grazing cows.

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Objetivo: Relatar a taxa de sobrevivência de implantes imediatos suportando overdentures mandibulares, em carga imediata, e o índice de sucesso dos tratamentos acompanhados por 36 meses. Métodos: Os implantes foram instalados em um projeto de extensão universitária que se propõe a reabilitar pacientes de baixa renda, com dentição seriamente comprometida. Quarenta e dois pacientes foram selecionados para o estudo. Em três casos, não se alcançou travamento primário compatível com o procedimento de carga imediata sobre implantes. Nesses pacientes, as próteses foram capturadas de forma convencional, após o período de osseointegração. Trinta e nove pacientes receberam o tratamento proposto. Três deles sofreram perda precoce de um dos implantes, todos ainda no primeiro mês após os procedimentos. Os implantes perdidos foram, posteriormente, substituídos e recapturados após três meses. Trinta e seis pacientes completaram o período de osseointegração sem apresentar perdas. Os pacientes passaram, então, a ser avaliados semestralmente, sendo que 25 completaram o estudo. Onze pacientes não compareceram às consultas de reavaliação por motivos variados. Resultados: A taxa de sobrevivência, até o final do período de osseointegração foi de 96,15%, isso é, 3 implantes perdidos em 78 imediatamente carregados. O índice de sucesso dos tratamentos acompanhados por 36 meses foi de 100%, uma vez que não foi observada nenhuma perda adicional de implantes. Conclusão: A reabilitação oral de pacientes que perderam todos os seus dentes mandibulares, por meio de overdentures sobre implantes imediatos não esplintados, em carga imediata, utilizando-se o sistema bola, mostrou-se muito satisfatório, com alta taxa de sobrevivência dos implantes, e alto índice de sucesso dos tratamentos acompanhados por 36 meses. O projeto de extensão tem observado resultados clínicos, tanto estéticos quanto funcionais, altamente satisfatórios, proporcionando uma melhora acentuada na autoestima e na qualidade de vida da população assistida.

Aim:This study aimed to report the survival rate of immediate implants supporting mandibular overdentures, which have been immediately loaded, and the success rate of the treatments followed up for 36 months. Methods: The implants were installed in a university extension project that seeks to rehabilitate low-income patients with seriously compromised dentitions. Forty-two patients were selected for the study. In three cases, the primary stability proved to be incompatible with the immediate loading procedure on implants. Thus, in these cases prostheses were captured conventionally after the period of osseointegration. Thirtynine patients received the proposed treatment. Three of them suffered an early loss of one of the implants, all in the first month after the procedures. The lost implants were replaced and recaptured after three months. Thirty-six patients completed the period of osseointegration without implant loss. The patients were evaluated every six months, and twenty-five patients completed the study. Eleven patients did not take part in the follow-up sessions for various reasons. Results: The survival rate until the end of the period of osseointegration was 96.15%, in other words, within the 78 immediately loaded implants, three were lost. The success rate of treatments followed up for 36 months was 100%, without additional loss of implants. Conclusion: The oral rehabilitation of patients using overdentures on immediate implants with immediate loading, using the ball system, proved to be very satisfactory, with a high survival rate of the implants, and high success rates of treatments followed up for 36 months.

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The objective of this study was to evaluate the intake and apparent digestibility of nutrients, as well as the feeding behavior of sheep fed an exclusively corn silage diet (0%); this diet incorporated wet corn gluten feed (WCGF) in increments of 30%, 50%, 60%, and 90%, together with the profile of the particles of these silages. Five crossbreed sheep were used with an average weight of 40 kg; they were housed in metabolic cages and were arranged in a Latin square 5×5 experimental design. There was a quadratic effect on dry matter (DM) intake, with a maximum consumption of 1.75 kg/day­1 to an inclusion of 39.09% of WCGF. The crude protein (CP) consumption exhibited an ascending linear effect with the inclusion of the co-product, and fiber consumption in neutral detergent fiber (NDF) and acid detergent fiber decreased linearly with the inclusion of WCGF. The apparent digestibility of DM, CP, and NDF increased linearly with the increasing inclusion of co-product in corn silage. Rumination time, total chewing, and idleness were influenced by increases in the inclusion of WCGF in corn silage, and there was a decreasing linear effect on the amount of time spent ruminating and total chewing, as well as an increasing linear effect for idleness duration. The chewing time for bolus, the number of chews for bolus, and the number of chews per day were influenced by the inclusion of WCGF. Through the obtained results, especially the equation of DM intake, which estimated a maximum point of 39.09%, as well as the presence of diarrhea at levels up to 50%, it was concluded that the addition of up to 40% of WCGF in corn silage can be recommended as it improves nutrient intake and features good digestibility without negatively altering the normal behavior of sheep.

Objetivou-se com este estudo avaliar o consumo, a digestibilidade aparente dos nutrientes, e o comportamento ingestivo de ovinos alimentados com dieta exclusiva de silagem de milho (0%), e acrescidas de 30, 50, 60 e 90% de farelo úmido de glúten de milho (FUGM), na matéria natural, juntamente com o perfil das partículas dessas silagens. Foram utilizadas cinco ovelhas sem raça definida com peso vivo médio de 40 kg, alojadas em gaiolas metabólicas, arranjadas no delineamento experimental em quadrado latino 5x5. Houve efeito quadrático para o consumo de matéria seca, com consumo máximo de 1,75kg/dia aos 39,09% de inclusão de FUGM. O consumo de proteína bruta sofreu efeito linear ascendente a com a inclusão do coproduto, e os consumos de fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA) diminuíram linearmente com a inclusão de FUGM. A digestibilidade aparente da MS, PB e FDN aumentaram linearmente com o aumento na inclusão do coproduto na silagem de milho. Os tempos de ruminação, mastigação total, e ócio foram influenciados pelo aumento na inclusão de FUGM na silagem de milho, houve efeito linear decrescente para o tempo em ruminação, e mastigação total, e efeito linear crescente para o tempo em ócio. O tempo de mastigação por bolo, número de mastigações por bolo, e o número de mastigações por dia, sofreram influencia da inclusão de FUGM. Através dos resultados obtidos, especialmente da equação de consumo de matéria seca, que estimou ponto de máximo de 39,09% e pela presença de diarreia em animais que consumiam níveis de inclusão acima de 50%, conclui-se que adições de até 40% de FUGM na silagem de milho são recomendadas devido ao fato do mesmo melhorar o consumo de nutrientes, tendo boa digestibilidade sem alterar negativamente o comportamento normal dos ovinos.

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For many vertebrate species, bite force plays an important functional role. Ecological characteristics of a species' niche, such as diet, are often associated with bite force. Previous evidence suggests a biomechanical trade-off between rodents specialized for gnawing, which feed mainly on seeds, and those specialized for chewing, which feed mainly on green vegetation. We tested the hypothesis that gnawers are stronger biters than chewers. We estimated bite force and measured skull and mandible shape and size in 63 genera of a major rodent radiation (the myomorph sigmodontines). Analysis of the influence of diet on bite force and morphology was made in a comparative framework. We then used phylogenetic path analysis to uncover the most probable causal relationships linking diet and bite force. Both granivores (gnawers) and herbivores (chewers) have a similar high bite force, leading us to reject the initial hypothesis. Path analysis reveals that bite force is more likely influenced by diet than the reverse causality. The absence of a trade-off between herbivores and granivores may be associated with the generalist nature of the myomorph condition seen in sigmodontine rodents. Both gnawing and chewing sigmodontines exhibit similar, intermediate phenotypes, at least compared to extreme gnawers (squirrels) and chewers (chinchillas). Only insectivorous rodents appear to be moving towards a different direction in the shape space, through some notable changes in morphology. In terms of diet, natural selection alters bite force through changes in size and shape, indicating that organisms adjust their bite force in tandem with changes in food items.

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Objetivo: Discutir a literatura a respeito dos temas:características dos alimentos utilizados e as tendências tecnológicas para a avaliação clínica da mastigação. Material e Métodos: A pesquisa foi realizada por três pesquisadores.Foram incluídos artigos gratuitos, completos, com seres humanos, de ambos os sexos, de qualquer idade, saudáveis ou não. A busca foi realizada no período entre setembro e dezembro de 2012, não havendo restrição quanto ao ano da publicação. Os descritores foram selecionados de acordo com os DeCS: “Fonoaudiologia”, “Tecnologia em Fonoaudiologia” e “Mastigação”. Outros descritores não catalogados na referida lista foram utilizados para ampliar a busca. Resultados: Foram encontrados 25 artigos na base de dados Scielo e 15 artigos na base de dados LILACS, totalizando 40 artigos. Tem-se o pão francês como o alimento mais sugerido, podendo ser oferecido com tamanho de aproximadamente de 2cm ou solicita-se ao paciente fazer a apreensão para avaliar o padrão mastigatório. Contudo para avaliar a mastigação de idosos com dentes naturais utilizam se pão e amendoim; e para avaliar a mastigação de idosos edêntulos totais utilizam-se bolo e salsicha. Conclusão: Não há padronização na avaliação da mastigação quanto ao tipo,tamanho e peso do alimento utilizado, nem tampouco explicação científica para os alimentos escolhidos e utilizados na clínica. Em relação aos equipamentos tecnológicos ainda há uma busca por padronização de métodos e protocolos para manuseio e compreensão dos resultados para atuação clínica.

Objective: To discuss the literature about the clinical assessment of chewing with regard to food features and technological trends. Material and Methods: This study included free complete articles, with humans, males and females, at any age, healthy or unhealthy. The searches were performed by three examiners in the period between September and December 2012, with no restriction of publication year, using the following DeCS descriptors:“Speech”, “Speech Technology” and “Chew”. Other descriptors not cataloged on the list were also used to expand the searches. Results: 25 articles were found in the SciELO database and 15 articles in the LILACS database, totaling 40 articles. Rolls have been the most commonly suggested food which can be used in small pieces (2 cm) or, alternatively, the patient can be asked to grasp them in order to be checked for chewing pattern. Bread and peanuts are commonly used to assess chewing in elderly patients with natural teeth,where as cake and sausage are indicated for edentulous elderlies. Conclusion: There is no standardization in the chewing assessment as to the food type, size and weight, nor a scientific explanation for the items chosen and used in the clinics. As to the technological equipment, there still is a search for standardization of methods and protocols to manage and understand the results under a clinical perspective.

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Avaliou-se o efeito de dietas distintas sobre o comportamento ingestivo (alimentação, ruminação e ócio) em ovinos. Dezesseis carneiros, castrados, confinados em gaiolas de metabolismo, com peso médio de 45,1kg, foram distribuídos aleatoriamente em quatro tratamentos: T1- silagem de cana + concentrado; T2- silagem de cana + concentrado + 15% de caroço de algodão; T3- silagem de cana e T4- feno de Tifton 85. Os animais foram submetidos à observação visual durante 24 horas a intervalos de 10 minutos. Houve diferença entre os tratamentos com relação aos tempos despendidos com alimentação e ócio, sendo que o tratamento com feno de Tifton 85 apresentou os mais altos valores, 6,04 h/dia, para o tempo de alimentação, e os mais baixos valores para o tempo de ócio, 7,50 h/dia.

The effects of different diets on the ingestive feeding behavior in wethers (feeding, ruminating and idle) were evaluated. Sixteen wethers with an average weight of 45.1kg were housed in metabolic cages and were randomly assigned to four treatments (T1- sugarcane silage + concentrate; T2- sugarcane silage + concentrate + 15% whole cottonseed; T3- sugarcane and T4- hay Tifton 85). The ingestive behavior was assessed by visual observation at 10 minute intervals for 24 hours. There were differences between treatments for time spent feeding and idle, and the treatment with Tifton 85 hay showed the highest values for feeding time, 6.04 h/day, and lower values for idle time, 7.50h/day.

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Avaliou-se o efeito de dietas distintas sobre o comportamento ingestivo (alimentação, ruminação e ócio) em ovinos. Dezesseis carneiros, castrados, confinados em gaiolas de metabolismo, com peso médio de 45,1kg, foram distribuídos aleatoriamente em quatro tratamentos: T1- silagem de cana + concentrado; T2- silagem de cana + concentrado + 15% de caroço de algodão; T3- silagem de cana e T4- feno de Tifton 85. Os animais foram submetidos à observação visual durante 24 horas a intervalos de 10 minutos. Houve diferença entre os tratamentos com relação aos tempos despendidos com alimentação e ócio, sendo que o tratamento com feno de Tifton 85 apresentou os mais altos valores, 6,04 h/dia, para o tempo de alimentação, e os mais baixos valores para o tempo de ócio, 7,50 h/dia.(AU)

The effects of different diets on the ingestive feeding behavior in wethers (feeding, ruminating and idle) were evaluated. Sixteen wethers with an average weight of 45.1kg were housed in metabolic cages and were randomly assigned to four treatments (T1- sugarcane silage + concentrate; T2- sugarcane silage + concentrate + 15% whole cottonseed; T3- sugarcane and T4- hay Tifton 85). The ingestive behavior was assessed by visual observation at 10 minute intervals for 24 hours. There were differences between treatments for time spent feeding and idle, and the treatment with Tifton 85 hay showed the highest values for feeding time, 6.04 h/day, and lower values for idle time, 7.50h/day.(AU)

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OBJECTIVES: The aim of this study was to observe the tooth loss over age in a sample of Brazilian patients and analyze their ability to chew, relating it to how much is the loss of oral function impact over the quality of life (QoL). MATERIALS AND METHODS: This is a single center, observational study and the data were collected through clinical examination followed of questionnaires to obtain sociodemographic information, the ability to chew (through the index of chewing ability [ICA]) and QoL (through Oral Health Impact Profile, OHIP-14). RESULTS: The sample was composed by 171 random volunteers with mean age of 47 (SD 15.2). Low number of natural teeth was associated with an increase of age (Spearman's rho correlation coefficient-0.7, P < 0.001, 2-tailed) and chew disability (ICA: chew's ability vs. disability) (Mann-Whitney U-Test, P < 0.001). Chew disability showed a negative impact over the QoL (overall OHIP; Mann-Whitney U Test P < 0.001) and in five of seven OHIP domains (Functional Limitation, Physical Pain, Psychological Discomfort, Physical Disability, Psychological Disability). Age over than 40 years, was also associated with chewing disability (Pearson Chi-Square P < 0.001) and poorer QoL (Mann-Whitney U test P = 0.01). CONCLUSION: This study observed that the chewing disability produces a significant and negative impact over oral-health related QoL and both, poor QoL and chewing disability are related with the decrease of the number of natural teeth.