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Purpose: To compare the endothelial coverage of different stents in porcine carotid arteries. Research problem: How effective are polyurethane stents (PU) and PU + rapamycin (PU + RAPA) compared to bare-metal stents on endothelial coverage by neointima in pigs after 28 days? Methods: The methodology had two phases for an interventional, experimental, prospective study, with three Moura pigs, 12 weeks old and weighing between 19 and 22.5 kg. In phase I, eight stents were implanted in carotid arteries; three stents coated with PU, three coated with PU + RAPA, and two without coating. After 28 days, phase II was carried out, consisting of euthanasia, removal of the stents, to evaluate the exposed area of the stent struts, and the percentage of endothelialization through optical microscopy and scanning electron microscopy. Results: The eight stents implanted with ultrasound sizing and post-dilation with a larger diameter balloon were analyzed by Doppler ultrasound, intravascular ultrasound, and angiography after 28 days. Conclusions: This study showed complete endothelial coverage by the endoluminal neointima of the stent struts, good integration and coverage with the arterial wall, with no exposed struts showing the presence of intimal hyperplasia (whitish tissue).

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Cleft palate is an oronasal communication that can affect the area comprehending the lips and the soft palate. Its clinical signs vary depending on the degree of the defect and the age of the animal, ranging from nasal secretion, coughing, sneezing, halitosis, respiratory difficulty, aspiration pneumonia, and loss of body condition. Its diagnosis is based on inspection of the oral cavity and imaging tests. Palatal defects must be surgically corrected as quickly as possible, using mucosal flaps, grafts, or implants. A desire to evolve alternative treatments for cleft palates drives the search for ways to manufacture customized pieces. 3D printing and biomaterials have enhanced in detail and applicability; combined with design tools and imaging exams, they allow for the making of precise implants and anatomical models for the planning and execution of surgical procedures. This report describes the case of a female, mixed-breed feline treated at a veterinary clinic; it was diagnosed with secondary cleft palate, had a history of falling, and underwent previous palatoplasties with recurrence. A surgical reintervention was performed to implant a 3D-printed TPU film to close its secondary cleft palate.(AU)

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The Brazilian Buriti oil presents low extraction costs and relevant antioxidant properties. Thus, this work aimed to analyze Buriti oil biomaterial (BB), within its physicochemical properties, biocompatibility and cellular integration, with the purpose to the use as a growth matrix for Goat Wharton's jelly mesenchymal stem cells. Biomaterials were produced from Buriti oil polymer (Mauritia flexuosa), for it's characterization were performed Infrared Region Spectroscopy (FTIR) and Thermogravimetric Analysis (TG and DTG). The biointegration was analyzed by Scanning Electron Microscopy (SEM) and histological techniques. In order to investigate biocompatibility, MTT (3-(4,5-dimetil-2-tiazolil)-2,5-difenil-2H-tetrazólio) test and hemolytic activity tests were performed. The activation capacity of immune system cellswas measured by phagocytic capacity assay and nitric oxide synthesis . The BB presented an amorphous composition, with high thermal stability and high water expansion capacity, a surface with micro and macropores, and good adhesion of Wharton's jelly mesenchymal stem cells (MSCWJ). We verified the absence of cytotoxicity and hemolytic activity, in addition, BB did not stimulate the activation of macrophages. Proving to be a safe material for direct cultivation and also for manufacturing of compounds used for in vivo applications.(AU)

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Objetivou-se relatar o emprego de uma tala externa confeccionada com material de poliuretano e cobertura interna de neopreme na reparação cirúrgica do pectus excavatum em um felino jovem. O felino apresentava deformidade anatômica congênita na região do externo e sinais clínicos respiratórios. Imagens avançadas de tomografia foram utilizadas para moldar a tala impressa com tecnologia tridimensional. Esta alternativa possibilitou melhor planejamento cirúrgico e, com isso, conforto para o paciente, além da qualidade própria do material de poliuretano que é levemente maleável, o que permitiu melhor moldagem e expansão torácica durante a respiração. A tala se provou resistente o suficiente para suportar a tração ocasionada pelos fios de sutura e possibilitou o reposicionamento adequado do osso esterno ao mesmo tempo que se mostrou confortável e acarretou mínimas lesões ao paciente.

The aim of this paper was to report the use of an external splint made of polyurethane material and internal neopreme covering in the surgical repair of a pectus excavatum in a young feline. The feline exhibited a congenital anatomical deformity in the external region and clinical respiratory signs. Advanced CT images were used to shape the 3D-printed splint. This alternative allowed better surgical planning and, therefore, comfort for the patient, this because to the quality of the polyurethane material, which is slightly malleable, and allowed for better molding and chest expansion during breathing. The splint proved to be strong enough to withstand the traction caused by the suture threads and allowed the proper repositioning of the sternum, at the same time it was comfortable and caused minimal injuries to the patient.

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Purpose: To analyze the influence of occlusive dressing on the healing of excisional skin wounds in mice. Methods: Pre-clinical, comparative, and translational study. Mice were divided into three experimental groups: wounds occluded with hydrocolloid (HD) dressings, transparent polyurethane film (TF) dressings, and without occlusion (WO), monitored at three, six and 14 days, with eight animals each. Closure rate, infiltration of neutrophils and macrophages, measurement of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) and, histologically, angiogenesis were evaluated. Results: Wound closure was accelerated in the occlusive groups. There was a decrease in TNF-α levels in the HD group when compared to the WO and TF groups. Neutrophils accumulation decreased in the HD group. Increased dosages of macrophages were evidenced in the HD group, compared to the WO and TF groups. Levels of VEGF were increased in the TF and HD groups. Conclusions: It is suggested that the occlusion of wounds modulates the inflammatory response.

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ABSTRACT Purpose The biomechanical properties of the polyurethanes implant material derived from castor oil plant (Ricinus communis) were evaluated in a noncritical bone defect model in rat tibia. Methods After three weeks of the implant application, the tibias were tested by means of the biomechanical three-point flexion test and resistance, rigidity, energy at maximum load and maximum energy were evaluated. Nonparametric statistical analysis was performed. Results It was found that the group that received the implant behaved the same as the intact control group and also showed a significant increase in maximum load compared to the spontaneous repair group. Conclusions Our results indicate that the tibias with the implant material in a noncritical bone defect recover normal biomechanical parameters in less time than spontaneously.

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Polymer coatings are used to control the rate of release of plant available nutrients from fertilizers as well as to reduce nutrient losses such as ammonia (NH3) volatilization. Although the literature presents several examples of materials used to coat urea, little is known about nitrogen (N) release properties such as the mechanism involved and phenomena (e.g., pore opening) in the polymer coating. Thus, this study investigated urea release from polyurethane (PU) derived from two renewable raw materials (castor oil and soybean oil), to explain how the oil structure and coating microstructure influence release and urea-N dynamics in soil. The results demonstrated that the profile of urea release and the urea-N mineralization in the soil could be controlled by altering the thickness of the coating on the urea granules. Coating by eco-friendly polymer was efficient in controlling urea release in soil to reduce volatilization of ammonia and increase the availability of N in the soil.

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ABSTRACT: We evaluated the influence of temperature on the ability of Salmonella Enteritidis (SE) to form biofilms on stainless steel, polyethylene, and polyurethane surfaces under different hygiene procedures. These materials were placed on SE culture and incubated at 42±1 ºC, 36±1 ºC, 25±1 ºC, 9±1 ºC, and 3±1 ºC for 4, 8, 12, and 24 h. Hot water at 45 ºC and 85 ºC, 0.5% peracetic acid solution, and 1% quaternary ammonia were used for hygienization. Biofilm formation occurred at all temperatures evaluated, highlighting at 3 ºC which has not been reported as an ideal temperature for the adhesion of SE to these materials. The SE adhered more often to polyethylene surfaces than to polyurethane and stainless steel surfaces (P<0.05). Peracetic acid and water at 85 ºC had similar hygienization efficiency (P<0.05) followed by quaternary ammonia whereas water at 45 ºC was not effective. SE adhered to these materials under low temperatures which to date have been deemed safe for food preservation.

RESUMO: Avaliou-se o efeito da temperatura na capacidade de Salmonella Enteritidis (SE) formar biofilme em superfícies de aço inoxidável, polietileno e poliuretano e diferentes processos de higienização. Corpos de prova destes materiais foram postos frente a culturas de SE e incubados a 42±1 ºC, 36±1 ºC, 25±1 ºC, 9±1 ºC e 3±1 ºC por 4, 8, 12 e 24 horas. Para a higienização foram testados água aquecida a 45ºC e 85 ºC e soluções de ácido peracético 0,5% e amônia quaternária 1%. Verificou-se a formação de biofilmes em todas as temperaturas avaliadas, ressaltando-se a 3 ºC, ainda não citada como propícia para adesão de SE. Houve maior adesão ao polietileno do que ao poliuretano e ao aço inoxidável (P<0.05). Para higienização, o ácido peracético e a água a 85 ºC tiveram ação semelhante (P<0.05), seguidos por amônia quaternária, enquanto que a água a 45 ºC não foi eficaz. Todos os materiais avaliados propiciaram a aderência de SE, mesmo sob temperaturas baixas, consideradas até então seguras para a conservação dos alimentos.

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Afecções do trato gastrointestinal de equinos podem causar distúrbios de coagulação devido à concentração elevada de mediadores inflamatórios que estimulam a hemostasia e inibem a fibrinólise, gerando um estado de hipercoagulação. Equinos submetidos à laparotomia no tratamento da síndrome cólica permanecem com cateter venoso durante vários dias para a administração de fluidos e fármacos no período pós-operatório e, a veia jugular é o principal local para a implantação de cateteres. Assim, o trauma vascular persistente causado pelo cateter, associado ao ambiente pró-trombótico induzido pela afecção gastrointestinal, aumenta o risco para o desenvolvimento de tromboflebite jugular. Objetivou-se avaliar as características físicas e ultrassonográficas da veia jugular canulada com cateter de poliuretano durante o período pós-operatório de equinos submetidos à laparotomia. O cateter foi inserido de forma asséptica à admissão e permaneceu por sete dias. A avaliação ultrassonográfica revelou o desenvolvimento de tromboflebite em um equino, 48 após o procedimento cirúrgico. Os demais equinos demonstraram espessamento da parede vascular no local de punção e pequenos trombos junto ao cateter. A monitoração ultrassonográfica demonstrou que a cateterização prolongada em equinos submetidos à laparotomia, seguindo o protocolo proposto, minimiza a lesão vascular e pode prevenir a tromboflebite jugular.(AU)

Coagulation abnormalities are usually associated with equine gastrointestinal disease due to the increased levels of inflammatory mediators, which promotes hemostasis and inhibit fibrinolysis, creating a hypercoagulable state. Horses underwent laparotomy to treat colic usually require a venous catheter for several days to administrate fluids and drugs during the postoperative period, and the jugular vein is the most frequent site for catheterization. Therefore, the persistent vascular trauma caused by an implanted catheter, associated with the prothrombotic environment induced by the gastrointestinal disorder, increases the risk for the development of jugular thrombophlebitis. The purpose of the present investigation was to evaluate physical and ultrassonographic features of the jugular vein cannulated with a polyurethane catheter during the postoperative period of horses underwent colic surgery. The catheter was inserted aseptically on admission and dwell time was seven days. Upon ultrasound examination, one horse developed thrombophlebitis 48 hours after surgery and the other horses showed thickened venous wall at puncture site and small clots associated to the catheter. Ultrasound monitoration showed that long-term catheterization in horses underwent colic surgery following the present protocol minimizes vascular trauma and could prevent jugular thrombophlebitis.(AU)

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The objective of this study was to evaluate the thermal comfort and performance of broilers in their initial stage of development utilizing two different heating systems. The experiment was conducted in two sheds placed on a commercial farm. The heating systems were: indirect heating furnace and radiation heating drums. At the beginning of the heating phase the birds were confined in an area corresponding to 360 m² in shed 1 and 180 m² in shed 2, delimited by polyurethane curtains, allowing a density of 58.8 birds m-². The variables: dry bulb temperature (Tdb), relative humidity (RH%) and temperature and humidity index (THI) were calculated. Measurements were performed using continuous reading data loggers at 15-minute intervals throughout the experimental period, which was a complete productive cycle for males. Differences were detected in the environmental variables during the period evaluated, as well as differences in performance were found as a function of the two heating systems. The heating system of the furnace presented UR ranging from 47-59% in relation to the drum system (51-57%), besides providing a more constant temperature and providing a greater distribution of heating. On the other hand, the drum system provided greater weight gain in the animals.

Objetivou-se comeste estudo avaliar o conforto térmico e desempenho zootécnico de frangos de corte em seu estágio inicial de desenvolvimento em função utilizando dois sistemas de aquecimento distintos. O experimento foi conduzido em dois galpões localizados numa propriedade comercial. Os sistemas de aquecimento foram: fornalha de aquecimento indireto e tambores de aquecimento por radiação. No início da fase de aquecimento as aves foram confinadas numa área correspondente a 360 m2 no galpão 1 e 180 m2 no galpão 2, delimitada por cortinas de poliuretano, possibilitando uma densidade de 58,8 aves m-2. Foram avaliadas as variáveis Temperatura de bulbo seco (Tbs), umidade relativa do ar (UR%) e calculado o índice de temperatura e umidade (ITU). As medições foram realizadas com o uso de dataloggers de leitura contínua da marca Hobbo em intervalos de 15 minutos, durante todo o período experimental, que foi de um ciclo produtivo completo para machos. Foram detectadas diferenças nas variáveis ambientais durante o período avaliado como também foram encontradas diferenças no desempenho zootécnico em função dos dois sistemas de aquecimento. O sistema de aquecimento por fornalha apresentou UR variando de 47-59% em relação ao sistema de tambores (51-57%), além de proporcionar temperatura mais constante e proporcionar maior distribuição de aquecimento. Por outro lado, o sistema de tambores proporcionou maior ganho de peso nos animais.

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Background: The hygiene procedures in poultry slaughterhouses consist in the use of hot water, detergent and sanitizing, configuring Sanitation Standard Operating Procedure (SSOP). These actions control contamination in food processing environments, especially by pathogenic microorganisms, which cause diseases with impact on public health and economic losses. The microbiological control of aerobic mesophiles, Staphylococcus aureus and Escherichia coli, are used as indicators of contamination. The hygienic-sanitary conditions on the surfaces of the poultry slaughterhouse cuttting room were evaluated, before and after cleaning and sanitizing procedures.Materials, Methods & Results: Conventional microbiology (Rodac plates and sponge for quantification of aerobic mesophiles, Staphylococcus aureus and Escherichia coli) and ATP-Bioluminescence were used to analyze the action of hot water and the active principles peracetic acid, quaternary ammonia and biguanide in the standard pre-operational hygiene procedure in the cutting room of the poultry slaughterhouse under Federal Inspection with slaughter capacity of more than 20.000 birds/h. The evaluations were performed on three lines of chicken thigh cuts at the same time and in a completely randomized manner on stainless steel surfaces, polyurethane belts and polyethylene boards. Samples were made in four replicates at the three surface totaling 108 assay for each microorganism. The samples were collected at the end of the cutting process, before and after washing the surfaces with hot water (between 45 and 50ºC) and after sanitization with 0.5% peracetic acid, 2% quaternary ammonia and 1% biguanide. The ATP-Bioluminescence method detected organic matter at all collected points and Rodac plates allowed a better recovery of microorganisms than sponges for quantification of aerobic mesophiles, E. coli and S. aureus.[...]

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Introduction: Wound healing is a progressive, essential and complex physiological process that occurs as a restorative response after a tissue injury. It involves three phases: inflammation, proliferation and maturation. Exogenous, endogenous and pathological factors may interfere in the cicatricial process in humans and animals by altering the balance between the synthesis, degradation and remodelling of collagen and elastic fibres. Diabetes mellitus is a progressive metabolic disease that alters elastogenesis and collagenesis and induces delays in the healing process. Scientific evidence suggests that mesenchymal stem cells modulate the cicatricial response. Thus the objective of this work was to perform stereological and morphometric analysis to determine the formation of dermal fibres in cutaneous fragments of a murine model of diabetes mellitus.Materials, Methods & Results: Histological sections were obtained from the cutaneous wounds of diabetic mice. The cutaneous wounds were previously treated with autogenous mesenchymal stem cells, physiological solution or polyurethane membrane. The histological sections were subsequently processed and stained for type 1 and 3 collagen fibres and elastic fibres using Picrosirius Red and Weigert staining, respectively. Histological sections stained with Picrosirius Red presented three types of birefringence under polarised light microscopy that corresponded to red colours for type 1 collagen and green and yellow colours for type 3 collagen. Weigert staining presented three colours for histological structures under white light microscopy that corresponded to black colours for elastic fibres, variations in colour from pink to purple for other structures and dermal attachments. The elastic fibres, represented by a black colour, presented in a heterogeneous form and were either identified as thin, punctiform or rectangular fibres or as elastic agglomerates.[....]

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This study aimed to develop a locking T-plate and to evaluate its mechanical properties in synthetic models. A titanium 2.7mm T-plate was designed with a shaft containing three locked screw holes and one dynamic compression hole, and a head with two locked screw holes. Forty T-shaped polyurethane blocks, and 20 T-plates were used for mechanical testing. Six bone-plate constructs were tested to failure, three in axial compression and three in cantilever bending. Fourteen bone-plate constructs were tested for failure in fatigue, seven in axial compression and seven in cantilever bending. In static testing higher values of axial compression test than cantilever bending test were observed for all variables. In axial compression fatigue testing all bone-plate constructs withstood 1,000,000 cycles. Four bone-plate constructs failure occurred before 1,000,000 cycles in cantilever bending fatigue testing. In conclusion, the locking T-plate tested has mechanical properties that offer greatest resistance to fracture under axial loading than bending forces.(AU)

O objetivo deste estudo foi desenvolver uma placa bloqueada em formato de T e avaliar as propriedades mecânicas em um modelo sintético. Uma placa-T em liga de titânio 2,7mm foi desenhada com uma haste contendo três orifícios para parafusos bloqueados e um orifício para realização de compressão dinâmica. 40 blocos de poliuretano em formato de T e 20 placas-T foram utilizados para os ensaios mecânicos. Seis montagens osso-placa foram testados até a falha, sendo três em força de compressão axial e três em flexão engastada. 14 montagens osso-placa foram testadas até a falha em fatiga, sendo 7 em força de compressão axial e 7 em flexão engastada. No teste estático, os valores mais altos foram observados em todas as variáveis no teste de compressão axial quando comparado à flexão engastada. Já nos testes de fadiga na força de compressão axial, todas as montagens osso-placa resistiram à 1000000 de ciclos. No teste de fadiga em flexão engastada, quatro montagens osso-placa falharam antes de alcançarem 1000000 de ciclos. Em conclusão, a placa-T estudada apresenta propriedades mecânicas que oferecem uma melhor resistência em estabilizar as fraturas na atuação das forças de compressão axial que nas forças de flexão.(AU)

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Os efeitos da esterilização por óxido de etileno sobre as propriedades físico-químicas da Poliureia permanecem desconhecidos, embora haja evidências de que o gás altera a funcionalidade de elastômeros de Poliuretano. Estabelecer esses efeitos é necessário, uma vez que eventuais alterações em propriedades físico-químicas, incitadas pelo método de esterilização, podem comprometer o desempenho funcional do polímero. Objetivou-se, com o presente estudo, avaliar se membranas de Poliureia esterilizadas por óxido de etileno diferem de membranas não esterilizadas, quanto aos parâmetros físico-químicos de intumescimento, degradação e porosidade e à morfologia de superfície analisada por microscopia eletrônica de varredura. As membranas de Poliureia foram sintetizadas usando uma química de sol-gel bem estabelecida na literatura científica. Comportamentos de intumescimento foram estudados usando método gravimétrico, com as amostras imersas em água deionizada, solução salina tamponada com fosfato de sódio e solução de ácido acético. A degradação foi estudada por imersão das amostras em tampão fosfato contendo tripsina pancreática suína, enquanto a porosidade foi avaliada por um método de imersão em etanol puro PA. A técnica de microscopia eletrônica de varredura utilizada envolveu elétrons secundários e análise de imagens pelo software ImageJÒ. Diferenças estatísticas entre as membranas esterilizadas e não esterilizadas por óxido de etileno foram consideradas significativas quando P < 0,05. Os resultados mostraram que as membranas esterilizadas e as não esterilizadas intumesceram, sem diferenças significativas (P < 0,05), em todos os meios de imersão. As taxas de imersão foram de 140-142% em água deionizada, 150-151% em solução salina tamponada com fosfato de sódio e de 30-35% em solução de ácido acético. O ensaio enzimático mostrou que as membranas analisadas (P > 0,05) e o método de imersão em etanol revelou porosidade de 20%. A microscopia eletrônica de varredura revelou que as superfícies das membranas nãoesterilizadas apresentam maiores contrastes topográficos, quando comparadas às membranas esterilizadas. Os valores médios ± desvios padrão de contrastes topográficos, em pixels, foram de 139,82 ± 58,64 para membranas não-esterilizadas e de 61,78 ± 32,35 para membranas esterilizadas (P < 0,05). Como conclusões, o presente estudo mostrou que a esterilização por óxido de etileno não alterou as propriedades físico-químicas da membrana de Poliureia. No entanto, a topografia de superfície foi alterada pelo método de esterilização, o que pode influenciar o desempenho funcional e as aplicações clínico-cirúrgicas do material.

The effects of ethylene oxide sterilization on the physicochemical properties of Polyurea remain unknown, although there is evidence that the gas alters the functionality of Polyurethane elastomers. Establishing these effects is necessary, since any changes in physicochemical properties, incited by the sterilization method, can compromise the functional performance of the polymer. The objective of the present study was to evaluate whether Polyurea membranes sterilized by ethylene oxide differ from non-sterilized membranes, in terms of the physicalchemical parameters of swelling, degradation, porosity, and the surface morphology analyzed by scanning electron microscopy (SEM). Polyurea membranes were synthesized using wellestablished sol-gel chemistry in the scientific literature. Swelling behaviors were studied using a gravimetric method, with samples immersed in deionized water, phosphate-buffered saline, and acetic acid solution. Degradation was studied by immersion of samples in phosphate buffer containing porcine pancreatic trypsin, while porosity was evaluated by an immersion method in pure ethanol PA. The SEM technique used involved secondary electrons and image analysis by the ImageJÒ software. Statistical differences between ethylene oxide sterilized and nonsterilized membranes were considered significant when P < 0.05. The results showed that sterile and non-sterile membranes swelled, without significant differences (P < 0.05), in all immersion media. Immersion rates were 140-142% in deionized water, 150-151% in s phosphate-buffered saline, and 30-35% in acetic acid solution. The enzymatic assay showed that trypsin did not degrade the analyzed membranes (P > 0.05) and the ethanol immersion method revealed a porosity of 20%. SEM revealed that the surfaces of non-sterilized membranes have greater topographical contrasts when compared to sterilized membranes. The mean values ± standard deviations of topographical contrasts, in pixels, were 139.82 ± 58.64 for unsterilized membranes and 61.78 ± 32.35 for sterilized membranes (P < 0.05). In conclusion, the present study showed that ethylene oxide sterilization did not change the physicochemical properties of the Polyurea membrane. However, the surface topography was altered by the sterilization method, which may influence the functional performance and clinical-surgical applications of the material.

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Pelvic fractures correspond to 20 to 30 % of the fractures observed in dogs. Complete fractures, especially with bone axis deviation should be surgically treated. The mechanical study of surgical techniques is of utmost importance to assess the best way of treating these injuries. This study compared, biomechanically, the use of a dynamic compression plate (DCP) and screws (group 1) or screws and polymethylmethacrylate (PMMA) (group 2) to stabilize an iliac fracture using a static test. Sixteen canine synthetic hemi-pelvises (test specimens) with a transverse iliac osteotomy were used. After fixation with implants, a load was applied to the acetabulum until failure. Group 1 maximal compressive load was 133.9±18.60 N, displacement at yield 21.10±3.59mm and stiffness 125.22±12.25N/mm. Group 2 maximal compressive load was 183.50±27.38N, displacement at yield 16.66±5.42mm and stiffness 215.68±33.34N/mm. The stabilization with polymethylmethacrylate was stronger than dynamic compression plate since it resisted a greater load in all test specimens.(AU)

As fraturas da pelve são frequentes em cães, correspondendo a 20-30% das fraturas encontradas na espécie. A grande maioria delas é tratada cirurgicamente, principalmente aquelas que apresentam desvio ósseo. O estudo mecânico das técnicas cirúrgicas é de extrema importância para avaliação da melhor maneira de tratamento destas lesões. O objetivo deste estudo foi comparar, do ponto de vista biomecânico, a fixação das fraturas do ílio utilizando uma placa de compressão dinâmica ou parafusos associados ao polimetilmetacrilato, por meio de um teste estático. Foram utilizadas 16 hemipelves caninas de origem sintética, nas quais uma osteotomia transversa foi realizada no corpo do ílio. As fixações foram divididas em dois grupos: fixação com placa de compressão dinâmica e parafusos (grupo1) ou parafusos associados ao polimetilmetacrilato (grupo 2). Posteriormente à fixação dos implantes foi aplicada uma carga no acetábulo de cada corpo de prova até a falha. O grupo 2 apresentou força máxima de aplicação de carga a média de 133.9±18.60N, deflexão 21.10±3.59mm e rigidez 125.22±12.25N/mm. O grupo 2 apresentou força máxima de aplicação de carga a média de 183.50±27.38N, deflexão 16.66±5.42mm e rigidez 215.68±33.34N/mm. A estabilização com o polimetilmetacrilato mostrou ser mais resistente, pois resistiu a uma maior quantidade de carga em relação à placa de compressão dinâmica, em todos os corpos de prova.(AU)

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ABSTRACT PURPOSE: To assess the capsules formed by silicone implants coated with polyurethane foam and with a textured surface. METHODS: Sixty-four Wistar albinus rats were divided into two groups of 32 each using polyurethane foam and textured surface. The capsules around the implants were analyzed for 30, 50, 70 and 90 days. Were analyzed the following parameters: foreign body reaction, granulation tissue, presence of myofibroblasts, neoangiogenesis, presence of synovial metaplasia, capsular thickness, total area and collagen percentage of type I and III, in capsules formed around silicone implants in both groups. RESULTS: The foreign body reaction was only present in the four polyurethane subgroups. The formation of granulation tissue and the presence of myofibroblasts were higher in the four polyurethane subgroups. Regarding to neoangiogenesis and synovial metaplasia, there was no statistical difference between the groups. Polyurethane group presented (all subgroups) a greater capsule thickness, a smaller total area and collagen percentage of type I and a higher percentage area of type III, with statistical difference. CONCLUSION: The use of polyurethane-coated implants should be stimulated by the long-term results in a more stable capsule and a lower incidence of capsular contracture, despite developing a more intense and delayed inflammatory reaction in relation to implants with textured surface.

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ABSTRACT: Often fractures of long bones in horses are comminuted and form bone gaps, which represent a major challenge for the fixation of these fractures by loss of contact between the fragments. Bone grafts help in treating this kind of fracture and synthetic materials have been gaining ground because of the limitations of autologous and heterologous grafts. In this study were performed compressive non destructive test in 10 bones with complete cross-bone gap in mid-diaphyseal of the third metacarpal bone of horses. Using a mechanism of "crossing" the 10 bones were used in the three groups (control, castor oil poliuretane and chitosan) according to the filling material. After the test with maximum load of 1000N bone had a gap filled by another material and the test was repeated. Deformations caused on the whole bone, plate and bone tissue near and distant of gap were evaluated, using strain gauges adhered to the surface at these locations. There was a reduction in bone deformation from 14% (control) to 3,5% and 4,8% by filling the gap with Chitosan and castor oil respectively, and a reduction of strain on the plate of 96% and 85% by filling gap with chitosan and castor respectively. An increase in intensity and direction of deformations occurred in bone near to gap after its filling; however, there was no difference in bone deformations occurring far the gap.

RESUMO: Frequentemente, as fraturas de ossos longos nos equinos são cominutivas, formando falhas ósseas, que representam um grande desafio no momento de sua fixação, devido à perda de contato entre os fragmentos. Os substitutos ósseos sintéticos auxiliam no tratamento desse tipo de fratura. Neste estudo, foram realizados ensaios compressivos não destrutivos em 10 ossos com falha óssea transversal completa em diáfise do terceiro metacarpiano de equinos. Utilizando um mecanismo de "crossing", os 10 ossos foram utilizados nos três grupos (controle, mamona e quitosana) de acordo com o material de preenchimento da falha. Para cada peça, realizaram-se ensaios referentes aos três grupos, com carga máxima de 1000N, por não se tratarem de ensaios destrutivos. Foram avaliadas as deformações causadas no osso, na placa e no tecido ósseo próximo e distante da falha, por meio de extensômetros. Observou-se que houve redução da deformação do osso de 14% (controle) para 3,5% e 4,8%, com o preenchimento da falha com quitosana e mamona, respectivamente. Houve redução da deformação na placa de 96% e 85% com o preenchimento da falha com quitosana e mamona, respectivamente. Houve aumento em intensidade e direção das deformações ocorridas no osso próximas à falha após seu preenchimento, contudo não se observaram diferenças nas deformações ocorridas no osso distantes a falha. Dessa forma, conclui-se que o preenchimento das falhas com quitosana e poliuretana de mamona trouxe benefícios quanto à redução das deformações no foco da fratura, alívio das cargas na placa, contudo elevou as cargas no tecido ósseo próximo à falha.

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ABSTRACT Unraveling the microbial diversity and its complexity in petroleum reservoir environments has been a challenge throughout the years. Despite the techniques developed in order to improve methodologies involving DNA extraction from crude oil, microbial enrichments using different culture conditions can be applied as a way to increase the recovery of DNA from environments with low cellular density for further microbiological analyses. This work aimed at the evaluation of different matrices (arenite, shale and polyurethane foam) as support materials for microbial growth and biofilm formation in enrichments using a biodegraded petroleum sample as inoculum in sulfate reducing condition. Subsequent microbial diversity characterization was carried out using Scanning Electronic Microscopy (SEM), Denaturing Gradient Gel Electrophoresis (DGGE) and 16S rRNA gene libraries in order to compare the microbial biomass yield, DNA recovery efficiency and diversity among the enrichments. The DNA from microbial communities in petroleum enrichments was purified according to a protocol established in this work and used for 16S rRNA amplification with bacterial generic primers. The PCR products were cloned, and positive clones were screened by Amplified Ribosomal DNA Restriction Analysis (ARDRA). Sequencing and phylogenetic analyses revealed that the bacterial community was mostly represented by members of the genera Petrotoga, Bacillus, Pseudomonas, Geobacillus and Rahnella. The use of different support materials in the enrichments yielded an increase in microbial biomass and biofilm formation, indicating that these materials may be employed for efficient biomass recovery from petroleum reservoir samples. Nonetheless, the most diverse microbiota were recovered from the biodegraded petroleum sample using polyurethane foam cubes as support material.

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Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

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Background: Thermography is a diagnostic imaging modality employed to estimate the degree of activity of some bodytissues. In theory, thermography would be expected to provide a graphical representation of inflammation and could therefore be used for early detection and monitoring of the inflammatory process. Given increased local temperature is one ofthe cardinal signs of inflammation, thermography could be an invaluable diagnostic method for musculoskeletal inflammatory conditions. The aim of this study was to investigate the ability of thermography to detect inflammation followingimplantation of ricin polyurethane polymer into experimental third metacarpal bone defects in horses.Materials, Methods & Results: A bone defect was produced in the proximal third of the metacarpal bone in 6 horses.Clinical examination of all horses was performed prior to surgery (control assessment; D0). A bone defect measuring13 mm in diameter was created in the proximal aspect of the left and right third metacarpal bones using a trephine saw.Bone defects in each horse were either filled with ricin polyurethane polymer and calcium carbonate (polymer limb) orleft untreated (control limb). Thermographic images were acquired 7, 15, 30, 60, 90 and 120 days following surgery. Athermal camera (Thermacam T400®) with 0.05°C thermal sensitivity was employed for infrared thermal image acquisitionand Rainbow High Contrast palette was selected. The distance between the camera and the subjects was adjusted so thatall images included the front limb from carpus to toe. Bandages were removed 30 min before data collection. Followingdemarcation of the proximal third metacarpal area on thermographic images, temperature readings were performed using built-in software and compared between polymer and control limbs. Mean temperatures were used in the analysis forincreased reliability. The Freidman test was employed to assess the progression of the variables studied along the experimental...