Resumo
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.
Assuntos
Animais , Gatos , Poliuretanos/uso terapêutico , Contenções/veterinária , Cirurgia Torácica/métodos , Anormalidades Congênitas/veterinária , Gatos/anormalidades , Tórax em Funil/veterinária , Impressão TridimensionalResumo
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.
Assuntos
Animais , Camundongos , Cicatrização , Ferimentos e Lesões , Inflamação/prevenção & controle , Animais de Laboratório , Curativos OclusivosResumo
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.(AU)
Assuntos
Animais , Ratos , Ricinus , Fenômenos Biomecânicos , Doenças Ósseas/veterinária , Próteses e Implantes/veterinária , PoliuretanosResumo
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.
Assuntos
Fertilizantes , Poliuretanos , Biodegradação Ambiental , Óleos de PlantasResumo
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.(AU)
Assuntos
Fertilizantes , Poliuretanos , Óleos de Plantas , Biodegradação AmbientalResumo
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.(AU)
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.(AU)
Assuntos
Salmonella enteritidis , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Biofilmes , Fatores Bióticos/análise , Temperatura BaixaResumo
ABSTRACT: 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.
RESUMO: 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.
Resumo
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.[....]
Assuntos
Masculino , Animais , Camundongos , Cicatrização , Colágeno Tipo III , Diabetes Mellitus , Pele/lesões , Transplante de Células-Tronco Mesenquimais , Interpretação Estatística de Dados , Modelos Animais de DoençasResumo
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.[....](AU)
Assuntos
Animais , Masculino , Camundongos , Transplante de Células-Tronco Mesenquimais , Colágeno Tipo III , Cicatrização , Pele/lesões , Diabetes Mellitus , Modelos Animais de Doenças , Interpretação Estatística de DadosResumo
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.(AU)
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.(AU)
Assuntos
Animais , Galinhas/anormalidades , Galinhas/crescimento & desenvolvimento , Sensação Térmica , Bem-Estar do AnimalResumo
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)
Assuntos
Tromboflebite/classificação , Gastroenteropatias/veterinária , Cavalos/anormalidades , Laparotomia/veterináriaResumo
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)
Assuntos
Tromboflebite/classificação , Gastroenteropatias/veterinária , Cavalos/anormalidades , Laparotomia/veterináriaResumo
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.[...]
Assuntos
Animais , Contaminação de Alimentos/prevenção & controle , Inspeção Sanitária , Matadouros , Saneamento/métodos , Escherichia coli , Galinhas , Staphylococcus aureusResumo
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.[...](AU)
Assuntos
Animais , Saneamento/métodos , Matadouros , Contaminação de Alimentos/prevenção & controle , Inspeção Sanitária , Galinhas , Escherichia coli , Staphylococcus aureusResumo
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.
Assuntos
Animais , Galinhas/anormalidades , Galinhas/crescimento & desenvolvimento , Sensação Térmica , Bem-Estar do AnimalResumo
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)
Assuntos
Titânio , Placas Ósseas , Suporte de Carga , Fenômenos Mecânicos , Próteses e ImplantesResumo
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)
Assuntos
Animais , Cães , Fenômenos Biomecânicos , Fixação Interna de Fraturas/veterinária , Fixadores Internos/veterinária , Pelve/lesões , Polimetil Metacrilato/uso terapêutico , Poliuretanos , Fraturas Ósseas/cirurgiaResumo
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)
Assuntos
Animais , Fixadores Internos/veterinária , Fixação Interna de Fraturas/veterinária , Pelve/lesões , Fenômenos Biomecânicos , Polimetil Metacrilato/uso terapêutico , Poliuretanos , Fraturas Ósseas/cirurgiaResumo
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)
Assuntos
Placas Ósseas/tendências , Fraturas Ósseas/terapia , Fenômenos MecânicosResumo
Purpose: To evaluate the polymer doped rods behavior with bioactive glass and hydroxyapatite for possible application as a fracture fixing method. Methods Twenty eight Rattus norvegicus Wistar underwent bone defect for access to the femoral medullary canal and distributed into three experimental groups: group A - doped castor bean polymer with bioactive glass; group B - castor bean polymer and; group C - castor bean polymer doped with bioactive glass and hydroxyapatite. After 15 and 60 evaluation days, the femurs were removed and sent for histology and scanning electron microscopy. Results Initially mild and moderate inflammatory infiltrate is observed that decreases as time goes by, and the presence of connective tissue capsule around the graft in all groups. Regarding the biomaterials resorption little was observed. The implanted rods did not favor the osteoconductive process in the femoral medullary canal which was observed only in the C15 group. Conclusions The association of castor bean polymer, bioactive glass and hydroxyapatite was biocompatible and osteointegrable. The osteoconductive only occurred in the presence of hydroxyapatite and bioactive glass (C15 Group) and little biodegradation was observed.(AU)