Les récepteurs à l’acétylcholine (AChRs) des nématodes parasites sont des cibles pharmacologiques majeures pour les anthelminthiques utilisés en médecine vétérinaire. Cependant, face à l’émergence d’isolats résistants, l’optimisation des stratégies de lutte nécessite une meilleure connaissance du mode d’action des anthelminthiques et du répertoire d’AChRs pour l’identification de nouvelles cibles thérapeutiques. Les nématodes parasites possèdent potentiellement une grande diversité d’AChR dont un nombre très restreint a été caractérisé fonctionnellement à ce jour. Dans ce contexte, nous avons identifié deux sous-unités d’AChR : ACR-26 et ACR-27 spécifiquement retrouvées chez les nématodes parasites. En exprimant ces sous-unités en œuf de Xénope et dans le nématode modèle Caenorhabditis elegans, nous avons mis en évidence un nouveau sous-type d’AChR musculaire sensible au morantel : le M-AChR. De plus, nous avons réalisé une étude moléculaire et fonctionnelle comparative des sous-unités d’AChR du groupe ACR-16 chez différentes espèces de nématodes. L’identification de ces nouveaux récepteurs constitue une base solide pour le développement de nouveaux anthelminthiques. / Acetylcholine receptors (AChRs) of parasitic nematodes are the major pharmacological targets for anthelmintics used in veterinary medicine. However, with the emergence of resistant isolates, the optimization of control strategies requires a better knowledge of the mode of action of anthelmintics and of the AChR repertoire for the identification of new therapeutic targets. Indeed, parasitic nematodes possess a large diversity of AChR subunits. In this context, we identified two AChR subunits: ACR-26 and ACR-27, specifically found in parasitic nematodes. By expressing these subunits in Xenopus oocytes and in the model nematode Caenorhabditis elegans, we identified a novel muscular AChR subtype sensitive to morantel: the M-AChR. Moreover, we performed a molecular and functional comparative study of the AChR subunits from ACR-16 group in different nematode species. The identification of these new receptors paves the way for the development of new anthelmintic drugs.

Made available in DSpace on 2015-04-14T13:29:38Z (GMT). No. of bitstreams: 1 423388.pdf: 875648 bytes, checksum: 6fa78c7588ba9b868b083818569e93a7 (MD5) Previous issue date: 2010-01-12 / A obten??o da passividade da estrutura met?lica ? resultado de um processo meticuloso que inclui procedimentos cl?nicos e laboratoriais. Um dos principais procedimentos laboratoriais causadores de distor??es ? a aplica??o do revestimento est?tico. Este estudo teve como objetivo avaliar, com utiliza??o de extens?metros, a distribui??o das tens?es geradas nos pilares prot?ticos de pr?teses totais fixas implantossuportadas, em fun??o do tipo de revestimento est?tico (resina acr?lica termopolimeriz?vel) e do n?mero de pilares (cinco e quatro pilares). Quatro barras met?licas em liga Prata-Pal?dio simularam pr?teses fixas tipo Protocolo Br?nemark sobre cinco implantes. Extens?metros foram colados nos pilares prot?ticos do modelo-mestre para medir a deforma??o antes (n=4 barras sem revestimento) e ap?s a aplica??o da resina acr?lica termopolimeriz?vel (Artigos Odontol?gicos Cl?ssico, S?o Paulo, Brasil) (n=4 barras com resina). Os valores de tens?o foram medidos com arranjo de cinco e de quatro pilares prot?ticos no modelo-mestre. Os dados de tens?o seguiram uma distribui??o normal. As m?dias de tens?o foram submetidas ? An?lise de Vari?ncia de Dois Fatores. N?o foi encontrada diferen?a estatisticamente significativa entre os fatores de varia??o (aplica??o do revestimento P=0,172; e n?mero de pilar P=0,523) e a intera??o entre os fatores (P=0,604). Os resultados deste estudo sugerem que, nesta simula??o de pr?teses do tipo protocolo Br?nemark, a aplica??o do revestimento de resina acr?lica termopolimeriz?vel n?o gerou varia??o significativa de tens?o nos pilares. Neste modelo experimental, o n?mero de pilares (quatro ou cinco) n?o afetou a tens?o no sistema, com ou sem revestimento de resina acr?lica.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-21T21:14:12Z No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-22T21:03:15Z (GMT) No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) / Made available in DSpace on 2018-02-22T21:03:15Z (GMT). No. of bitstreams: 1 JucikleciaDaSilvaReinaldo_TESE.pdf: 5032340 bytes, checksum: b1beaa4ac0c047c8890f7084d295b5df (MD5) Previous issue date: 2017-11-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho foi realizado um estudo para investigar a influ?ncia da estrutura qu?mica no comportamento reol?gico na regi?o da viscoelasticidade linear das blendas polim?ricas constitu?das de pol?meros acr?licos (poli(metacrilato de metila) homopol?mero (PMMAh), poli(metacrilato de metila) com elast?mero (PMMAe)) e estir?nicos (poliestireno (PS), copol?mero estireno-acrilonitrila (SAN), copol?mero acrilonitrila-butadieno-estireno (ABS) e copol?mero metacrilato de metila-butadieno-estireno (MBS)). A espectroscopia de infravermelho por transformada de Fourier (FTIR) mostrou diferentes bandas caracter?sticas das estruturas qu?mica e a calorimetria explorat?ria diferencial (DSC) identificou as temperaturas de transi??o v?trea (Tg) relacionadas aos acr?licos, estir?nicos e fase elastom?rica do PMMAe, ABS e MBS. Os resultados da composi??o qu?mica do SAN e ABS mostraram que a porcentagem de AN encontravam-se dentro da janela de miscibilidade para as misturas com o PMMA, isto ?, de 25 e 21%, respectivamente. Os resultados reol?gicos a baixas frequ?ncias na regi?o de viscoelasticidade linear mostraram que houve uma mudan?a significativa no comportamento reol?gico em rela??o ao uso do PMMAh, quando comparado ao uso do PMMAe e, mostraram tamb?m, a miscibilidade e imiscibilidade das blendas polim?ricas com varia??o estrutural dos componentes minorit?rios. A microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de transmiss?o (MET) mostraram a imiscibilidade nas blendas polim?ricas com PS e miscibilidade da blenda PMMAh/SAN, e tamb?m a miscibilidade entre o PMMAh com SAN livre do ABS na blenda PMMAh/ABS, corroborando com os resultados reol?gicos. Entretanto, as blendas polim?ricas com PMMAe apresentaram resultados microrreol?gicos complexos, devido a presen?a da fase elastom?rica. As fotomicrografias mostraram a miscibilidade entre o PMMA e o SAN nas blendas PMMAe/SAN e PMMAe/ABS, onde o PMMAe apresentou part?culas do tipo casca-n?cleo (core-shell) e o ABS apresentou dom?nios de fase dispersa de polibutadieno. / The aim of this work was to investigate the influence of the effect of the chemical structure on the rheological behavior in the linear viscoelastic region of polymer blends consisting of acrylic polymers (poly (methyl methacrylate) homopolymer (PMMAh), poly (methyl methacrylate) with elastomeric particles (PMMAe)) and styrenic polymers (polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS) and methyl methacrylate-butadiene-styrene copolymer (MBS)). Fourier transform infrared spectroscopy (FTIR) showed a different bands characteristic of the chemical structures and tje differential scanning calorimetry (DSC) identified the glass transition temperatures (Tg) related to acrylics, styrenics and elastomeric phases of PMMAe, ABS and MBS. The results of the chemical compositions of the SAN and ABS showed that the percentage of AN were within the miscibility window for mixtures with PMMA, ie 25 and 21 wt%, respectively. The rheological results obtained at low frequency in the region of linear viscoelasticity showed that there was a significant change in the rheological behavior in relation to the use of PMMAh when compared to the use of PMMAe and also showed the miscibility and immiscibility of the polymer blends with structural variation of the minority components. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the immiscibility in polymer blends with PS and miscibility in PMMAh/SAN blend, as well as the miscibility between PMMAh and free SAN of the ABS in the PMMAh/ABS blend, corroborating with the rheological results. However, the polymer blends with PMMAe presented complex microrreological results due to the presence of the elastomeric phase. Photomicrographs showed the miscibility between PMMA and SAN in the PMMAe/SAN and PMMAe/ABS blends, where PMMAe presented core-shell particles and ABS showed dispersed phase domains of the polybutadiene.

Background: Research suggests that cervical spine CT examination is over used for potential injury due to blunt trauma. Education of emergency providers regarding evidence-based guidelines can help reduce the over-use of CT examination, and the development of an evidence-based protocol for the management of patients with suspected cervical spine trauma may help promote more appropriate clinical use of radiologic imaging for cervical spine clearance. Purpose: The ultimate goal of this project is to develop a best-practice, evidence-based protocol for the management of patients with suspected cervical spine injury, in order to promote safe and efficient clinical clearance, as well as promote judicious and appropriate use of diagnostic imaging for suspected cervical spine injury. Methods: A retrospective chart review of emergency radiographic imaging studies obtained over a three-month timeframe for suspected cervical spine injury at a 300-bed hospital in Tucson, Arizona was performed to compare ordering practices with the ACR-AC. Descriptive statistics were used for data analysis. A web-based survey was conducted of facility stakeholders including emergency physicians, nurse practitioners and physician assistants regarding their views about clinical guidelines and protocols for radiographic and clinical clearance of cervical spine injury. Descriptive statistics and thematic analysis was used for survey responses. Results: Analysis of 263 imaging studies over a three-month timeframe demonstrated that 24.3% of cervical spine imaging studies obtained in three-month timeframe would be considered not appropriate based on the ACR-AC. The survey of emergency clinicians revealed that none of those who responded have a preference for referring to the ACR appropriateness criteria, and the majority of respondents did not support the implementation of a hospital protocol for the management of patients with suspected cervical spine trauma. Recommendations: An institutional protocol for suspected cervical spine injury developed from the ACR-AC with incorporation of clinical clearance criteria is recommended. To promote clinician acceptance, overcome resistance to implementation, and promote individualized patient care, the protocol should also include provider education and should allow for variance based on individual patient circumstances.

From its discovery, crack closure was recognized as a key aspect in understanding the fatigue crack growth process. Considering the condition of plane stress, a vast amount of research has been conducted experimentally, analytically, and numerically to understand the complex process of fatigue crack growth and crack closure. Nonzero crack opening stress values are routinely observed, and it seems that there is a general agreement regarding the incidence of the phenomenon under plane stress. However, investigations regarding crack closure under plane strain conditions are less abundant. Moreover, the existence of crack closure under the plane strain state of the stress has been questioned. The importance of accurate measurements of closure to predict adequately fatigue crack growth rates should not be underestimated. Models employed to predict fatigue crack growth rates rely on plasticity-induced crack closure concepts, and the validity of plasticity-induced crack closure depends on crack closure measurements. Crack closure measurements can be performed with Elber’s Method, the ASTM standard(Compliance offset method), or it may be done alternatively by the compliance ratio (CR) or the adjusted compliance ratio method (ACR). In this research, a small scale yielding two-parameter modified boundary layer analysis is performed to study the occurrence of plasticity-induced fatigue crack closure under constant amplitude loading and plane strain conditions. A wide range of T-stresses and KI levels are considered in the finite element analysis with the purpose of exploring the behavior of the crack opening stress. Crack closure was observed for some values of T-stress. Other values of T-stress resulted in an absence of closure under steady state conditions. In addition, an elastic-plastic finite element model was used to simulate a growing fatigue crack with WARP3D software. The computed displacements were used to determine the effective stress intensity factor range ΔKeff with the ASTM standard compliance offset approach, the (CR) method, and the (ACR) method. Finally, measurement location effects on ACR and the ability of ACR method to remove residuals stresses were investigated.

No description available.

Rheumatoid arthritis (RA) is an autoimmune disease, which causes joint inflammation. Different environmental and genetic factors such as smoking, anti-citrullinated protein antibody, rheumatoid factor, and certain MHC-alleles cause RA. It affects mostly women and it is characterised by joint swelling, pain, tiredness, and stiffness. Untreated RA can lead to disability and complications in different organs (brain, lung, heart,). The body develops tolerance against self-antigens using different mechanisms, including Tregs mediated, by increasing the expression of inhibitory receptors and through receptor modification/destruction of self-reactive cells.  Failure in the resistance development mechanism leads to autoimmune diseases. The most important cellular components of RA dependent inflammation are macrophages, T-cells, and B-cells. These cells contribute to the inflammations process by producing antibodies, cytokines, and through antigen presentation or immune cell activation. One of the cytokines, which are released by macrophages and T-cells is Tumour necrosis factor (TNF). It stimulates angiogenesis, activation of osteoclasts and the production of different cytokines by increasing the expression of NF-kB.  The diagnostic process of RA consists of serological, physical, and radiological examinations. These examinations together with other factors are utilized for calculating score (0-10), in order to decide if a patient have RA or not. The treatment of RA depends on disease activity and it is composed of NSAID, steroids, DMARDs, biological DMARDs and non-pharmacological treatment. The interventions can be given as a monotherapy or in combination. The disease activity of RA or the efficacy of a drug which is used to treat RA can be studied by ACR response, DAS-28, HAQ-DI score using joint progression score. The aim of the study was to investigate the efficacy and safety of adalimumab, as well as to compare it with other treatments, which are used to in RA. 5 scientific articles which were obtained from PubMed were used to perform the study. The keywords used to get the materials was” adalimumab rheumatoid arthritis”. It gave 172 results and 5 of the first 20 were selected. ACR 20 response and change in DAS-28 were studied as a primary efficacy endpoint. The result of the studies demonstrated that adalimumab had a moderate-god effect against RA according to the ACR/ EULAR criteria. However, adalimumab was less effective comparing to barcitinib, tocilizumab, sirukumab but it had a similar efficacy as ABP 501 as well as abatacept.   ACR response, change in DAS-28 and remission rate showed better results in patients who treated by sirukumab, tocilizumab or barcitinib. The studies have also proved that adalimumab leads to better outcomes when it is used in combination with methotrexate instead of monotherapy. Regarding safety, all the drugs showed similar patterns and nasopharyngitis as well as lung infections were the most common adverse events. More studies are required in order to find the perfect target molecule and combination therapy so that RA can be treated efficiently and at a lower cost.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-06-04T14:42:13Z No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-11T14:34:47Z (GMT) No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) / Made available in DSpace on 2018-06-11T14:46:48Z (GMT). No. of bitstreams: 1 DISSERTA??O FINAL - ANGELO ABEL.pdf: 2908441 bytes, checksum: 7b4f57513c25b05da3fbcc36003b7939 (MD5) Previous issue date: 2017-09-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, the sample-flame propagation indexes were simulated in laboratory, in detriment and in comparison to the generalized burning during the fires in internal environments. The respective chemical and physical properties of the paints, the emanated gases, were compared; evidencing its toxicities, toxicological thresholds and using the tests of horizontal burning and vertical burning. In the experimental part, the paint films were produced for later burning in a quartz chamber with the use of the electric furnace, from which the gases were collected, according to each thermal degradation orientation obtained by the TGA pallet, in order to analyze the toxicities in gas chromatography. In the results the different firing behaviors for each paint can be compared by virtue of its physico-chemical composition, together with its gas release rates in each temperature range. / Neste trabalho produziu-se a partir das tintas acr?licas ? base d??gua, os ?ndices de propaga??o de chama amostral e simulada em laborat?rio, em detrimento e em comparativo ? queima generalizada durante os inc?ndios em ambientes internos. Foram comparadas as respectivas propriedades qu?micas e f?sicas das tintas, dos gases emanados; evidenciando as suas toxicidades, limiares toxicol?gicos e empregando os testes de queima horizontal e queima vertical. Na parte experimental foram produzidos os filmes de tintas, para posterior queima em c?mara de quartzo com o uso do forno el?trico, onde a partir deste, coletou-se os gases, segundo cada orienta??o de degrada??o t?rmica obtida pala TGA, para ent?o serem analisadas as toxicidades em cromatografia gasosa. Nos resultados podem ser comparados os diferentes comportamentos de queima para cada tinta em virtude de sua composi??o f?sico-qu?mica, juntamente com suas taxas de libera??es de gases em cada faixa de temperatura.

Made available in DSpace on 2016-04-28T20:18:30Z (GMT). No. of bitstreams: 1 2008 - Vinicius Villas Boas de Brito.pdf: 2268646 bytes, checksum: e949027c863bdba33b474d06d53aaebc (MD5) Previous issue date: 2008-08-29 / Six different frames of low cost external skeletal fixators used in veterinary orthopedics were submitted to mechanical evaluation of the axial compression. The apparatuses were separated in two different models, one with wooden connection bars (Pinnus ellioti) and another with PMMA (polymethylmethacrylate) connection bars. Tubes of polyvynil chloride (PVC) were used to simulate the bone model. Each model were respresented by frames elaborated in typo Ib configuration, with eight insertion pins (four per fragment/ two per connection bar in each fragment), 12 insertion pins (six per fragment/ three per connections in each fragment) and 16 insertion pins (eight per fragment/ four per connection bar in each fragment). We have employed a universal essay machine, model 4204, Instron, at a two cm/min speed to submit the models to axial compression force tests and thus calculate their stiffness, safety load and yield point. Within the results, stiffness increase with a higher number of insertion pins; significant difference between the two models of connection bars is not detected. Otherwise the strength necessary to promote a one milimeter displacement at the fracture gap (safety load) is higher at the wooden connection bars apparatuses; this value also increases if the number of fixation pins is elevated, except if we compare frames with 12 insertion pins (six per fragment/ three per connections in each fragment) and 16 insertion pins (eight per fragment/ four per connection bar in each fragment). The strength necessary to promote a permanent deformation at the apparatuses (yield point) do not show significant statistic difference. / Foram submetidos ? avalia??o mec?nica de compress?o axial seis diferentes conforma??es de fixadores esquel?ticos externos de baixo custo para aplica??o em ortopedia veterin?ria. Os aparelhos se diferenciavam em dois modelos, um com barras de conex?o de madeira (Pinnus ellioti) e outro com barras de conex?o de resina acr?lica autopolimeriz?vel. Foram utilizados tubos de policloreto de vinila (PVC) para simular os fragmentos ?sseos. Cada modelo possu?a aparelhos montados na configura??o tipo Ib, com oito pinos de inser??o (quatro por fragmento/ dois por barra de conex?o em cada fragmento), 12 pinos de inser??o (seis por fragmento/ tr?s por barra estabilizadora em cada fragmento) e 16 pinos de inser??o (oito por fragmento/ quatro por barra de conex?o em cada fragmento). Os corpos de prova foram submetidos ? for?a de compress?o axial pela m?quina de ensaio universal, modelo 4204, Instron, a velocidade de dois cm/min. Sendo mensurados a rigidez, carga m?xima de seguran?a e o ponto de escoamento. De acordo com os resultados, a rigidez aumenta de forma diretamente proporcional ao incremento no n?mero de pinos de inser??o; n?o ? observada diferen?a significativa entre os dois tipos de barras de conex?o. Por?m o valor de for?a necess?ria para causar um deslocamento de um mil?metro no foco de fratura (carga m?xima de seguran?a) ? mais elevado nos aparelhos com barras de conex?o de madeira; esse valor aumenta tamb?m com o incremento do n?mero de pinos de inser??o, excetuando-se quando se compara aparelhos com 12 pinos de inser??o (seis por fragmento/ tr?s por barra estabilizadora em cada fragmento) e 16 pinos de inser??o (oito por fragmento/ quatro por barra de conex?o em cada fragmento). J? os valores da for?a necess?ria para causar uma deforma??o permanente nos aparelhos (ponto de escoamento) n?o apresentaram diferen?a estatisticamente significativa.