Bone defects created after curettage of benign bone tumors are customarily filled with solid poly(methyl methacrylate) (PMMA) or other bone substitutes. In this study, we depicted a porous PMMA-based cement (produced by mixing sodium bicarbonate and citric acid) and evaluated the prospect of its clinic application. Cement samples were characterized by high-performance liquid chromatography (HPLC) coupled to mass spectrometry and its cytotoxicity evaluated in fibroblast cultures. Implantation in rabbits allowed the histologic analysis of bone, kidneys, and liver for toxicity and coagulation tests, and MRI images for hemostasis evaluation. Osseointegration was analyzed through radiography, microtomography (micro-CT), SEM, and histology of sheep specimens. Rabbit specimens were analyzed 1, 4, and 7 days after implantation of porous or solid bone cement in 6.0 mm femoral defects. Sheep specimens were analyzed 3 and 6 months after implantation or not of porous or solid cement in 15.0 mm subchondral tibial defects. The production process did not release any detectable toxic substance but slightly reduced fibroblast proliferation in vitro. Until 7 days after surgery, no local or systemic alterations could be detected in histology, or hematoma formation in histology or MRI. Sheep implants showed 6 mm linear ingrowth from the bone-cement interface and 20% bone ingrowth considering the whole defect area. Radiography, micro-CT, SEM, and histology confirmed these findings. We conclude that our porous PMMA-based cement is an attractive alternative treatment for bone defect filling that combines osseointegration and early weight bearing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 649-658, 2018.

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Biomaterials’ structural characteristics and the addition of osteoinductors influence the osteointegration capacity of bone substitutes. This study aims to identify the characteristics of porous and resorbable bone substitutes that influence new bone formation. An Internet search for studies reporting new bone formation rates in bone defects filled with porous and resorbable substitutes was performed in duplicate using the PubMed, Web of Science, Scielo, and University of São Paulo Digital Library databases. Metaphyseal or calvarial bone defects 4 to 10 mm in diameter from various animal models were selected. New bone formation rates were collected from the histomorphometry or micro-CT data. The following variables were analyzed: animal model, bone region, defect diameter, follow-up time after implantation, basic substitute material, osteoinductor addition, pore size and porosity. Of 3,266 initially identified articles, 15 articles describing 32 experimental groups met the inclusion criteria. There were no differences between the groups in the experimental model characteristics, except for the follow-up time, which showed a very weak to moderate correlation with the rate of new bone formation. In terms of the biomaterial and structural characteristics, only porosity showed a significant influence on the rate of new bone formation. Higher porosity is related to higher new bone formation rates. The influence of other characteristics could not be identified, possibly due to the large variety of experimental models and methodologies used to estimate new bone formation rates. We suggest the inclusion of standard control groups in future experimental studies to compare biomaterials.

Despite the small sample size included in the present study, it seems that microlaparoscopic pyloromyotomy is safe and feasible with the lowest rate of complications and the shortest operative time. The Bianchi approach is a good alternative to achieve a small scar without laparoscopy.

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RESUMOAs náuseas e ou vômitos no pós-operatório são as principais complicações após procedimentos anestésicocirúrgicos, ocorrendo em cerca de 20 a 30% dos pacientes, contribuindo para a demora do retorno às funções normais, a elevação dos custos hospitalares e o menor grau de satisfação do paciente. O objetivo desta pesquisa foi caracterizar pacientes com sintomas de náuseas e vômitos nas primeiras 24 horas de pósoperatório. Estudo descritivo, desenvolvido em Enfermarias Cirúrgicas e A coleta de dados no pré-operatório foi realizada por meio de entrevista estruturada e exame físico e os dados relacionados aos períodos intra e pós-operatórios foram coletados por meio de análise de prontuário. Dos 100 participantes do estudo, sete apresentaram náuseas e vômitos. Esses sintomas foram mais frequentes nos sujeitos do sexo feminino, que não fumavam, com idade superior a 46 anos e obesos ou sobrepesos. O número reduzido de pacientes que apresentaram náuseas e vômitos no pós-operatório pode estar relacionado à prevenção desses sintomas no pós-operatório ou ao não registro das náuseas e vômitos pelos profissionais.Palavras-chave: Náusea. Vômito. Náusea e Vômito Pós-operatório. Cuidados Pós-operatórios. Enfermagem. ABSTRACTThe postoperative nausea and vomiting are the main complications after anesthetic-surgical procedures, occurring in about 20 to 30% of patients, helping to delay the return to normal function, the rise in hospital costs and lower degree of patient satisfaction. The aim of this study was to characterize patients with symptoms of nausea and vomiting in the first 24 hours postoperatively. A descriptive study developed in Surgical Wards and Anesthetic Recovery Unit, Hospital das Clinicas, Faculty of Medicine of Ribeirão Preto, University of São Paulo. Data collection preoperatively was conducted by structured interview and physical examination and data related to the intra and post-operative data were collected through review of medical records. Of the 100 study participants, seven had nausea and vomiting. These symptoms were more common in female subjects, who did not smoke, older than 46 years and classified as obese or overweight. The small number of patients who experienced postoperative nausea and vomiting may be related to prevention of these symptoms postoperatively or no record of nausea and vomiting by professionals.

RESUMO -Como a cor é um importante atributo relacionado ao apelo visual e à qualidade de produtos alimentícios, a redução das perdas de pigmento durante o processamento dos alimentos é uma preocupação básica para a indústria. Nesse contexto, o conhecimento de modelos cinéticos de destruição térmica é essencial no desenvolvimento de novos processos que forneçam a máxima retenção dos fatores de qualidade. Somando a isso a atual tendência mundial em usar pigmentos naturais, estudou-se a cinética de degradação térmica de betalaínas (na forma de betaninas) extraídas por processo alcoólico de Beta vulgaris L. (beterraba) entre 50 e 80 °C, para pH 3,0. As constantes cinéticas de degradação (Kd) e os tempos de meia-vida (t ½) foram obtidos para 50, 60, 70 e 80°C. O modelo cinético foi assumido como de primeira ordem e os t ½ diminuíram à medida que a temperatura do tratamento foi aumentada, assim como o esperado. Através da equação de Arrhenius, a energia de ativação e o fator de frequência para as betaninas foram determinados como sendo de 20,72 kcal/gmol e 3,09 s -1 , nessa ordem. INTRODUÇÃOAs preferências instintivas levam a prática do consumo de alimentos coloridos naturalmente além de que as alterações nos hábitos alimentares de consumo têm levado à evolução desses produtos alimentares (Reyes et al., 2007;Volp et al., 2009). Minimizar as perdas de pigmento durante o processamento é a preocupação primária para a indústria processadora -no processo industrial se faz necessário o monitoramento contínuo dessa troca de cor de forma a garantir a qualidade do produto (Shao-qian et al., 2011).A cinética de degradação da cor em alimentos é complexa. Modelos seguros que predizem corretamente o processo da reação química ocorrendo em líquidos homogêneos ou fases semi-sólidas durante os processos térmicos e armazenamento são proveitosos em muitas aplicações da engenharia incluindo processos de otimização. Portanto, estudos experimentais e aplicação de modelos para predizer e interpretar parâmetros cinéticos como a ordem de reação, a taxa de reação e a energia de ativação são necessários (Ahmed et al., 2002b). Além disso, modelos cinéticos de destruição térmica são essenciais para desenvolver novos processos, assumindo um produto alimentício seguro e fornecendo a máxima retenção dos fatores de qualidade (Ávila e Silva, 1999). Steet & Tong (1996), Weemaes et al. (1999), Guunawan e Barringer (2000), Ahmed et al. (2002 a, b), Antelo et al., 2008 e Patras et al. (2010 tem considerado a cinética de degradação da cor como seguindo uma reação de primeira ordem.Frente à atual tendência mundial em usar pigmentos naturais como corantes para alimentos, ênfase tem sido dada à busca de fontes economicamente viáveis (Lima et al., 2005). Neste contexto, destacamse as betalaínas, pigmentos naturais responsáveis pela coloração da beterraba vermelha e incluem duas Área temática: Engenharia e Tecnologia de Alimentos 1

Large metaphyseal bone defects created after benign bone tumor curettage are usually treated by solid bone cement (PMMA) implantation. Porous and absorbable cements are expected to improve clinical results by lowering incidence of aseptic loosening, heat promoted bone necrosis, bone/cement mechanical discrepancies and absence of bone integration. Effervescent components like sodium bicarbonate and citric acid can be mixed to PMMA producing porous cement that fits intraoperative requirements. Furthermore, castor oil polyurethane is a well-known absorbable cement that can be mixed to effervescent components to produce porous and absorbable bone cement. In vivo and in vitro toxicity of both products have never been tested to support its clinical use. The spurious production of toxic elements and the effect of citrate, an anticoagulant byproduct of the effervescent components reaction, were analyzed. In vitro experiments: The three experimental groups consisted of PMMA or one of the commercially available castor oil polyurethane cements (Poliquil ® or Bioosteo ®) mixed to the effervescent components specimens. These groups were compared to classic PMMA solid cement specimens. All the elements produced during preparation and incubation of the cements were analyzed by High Efficiency Liquid Chromatography coupled to Mass Spectrometry and by Resazurine microplate assay of NIH/3T3 and MRC-5 fibroblasts strains culture. In vivo experiments: Femoral defects were created in six rabbits per group and filled with PMMA or Poliquil ® porous cements or left empty. Magnetic resonance of the limb, histology of the limb, kidneys and liver, and coagulation parameters of blood samples collected immediately after and 1, 4 and 7 days after surgery were analyzed. Castor oil polyurethane of both brands (Bioósteo ® and Poliquil ®) released 4,4'-diaminodiphenylmethane. The Poliquil ® brand released 4,4'-diphenylmethane diisocyanate too. Both compounds are considered toxic. The MRC-5 and NIH3T3 cell strains proliferation was decreased in less than 80% in contact with polyurethane cements and less than 65% with PMMA, compared to the control group. Dilution of the medium diminished this effect. We believe that the acidity of the medium due to incomplete reaction of the effervescent components may be the cause of this finding. Liver and kidneys histology showed some slight changes in the same proportion as the control group. We infer that the cements do not cause acute systemic toxicity. In all groups, histologic analysis of the operated area showed small hematomas and a slight foreign body reaction. Significant 12 inflammatory reaction could not be found in any of the study groups. Citrate formation from the effervescent components reaction seems to not interfere with coagulation. Inflammatory reaction around porous cements is similar to that of classic solid PMMA cement. The cytotoxic effect observed in vitro, could not be detected in vivo. Coagulation parameters did not changed at any time after surgery. Magnetic resonance imaging evaluatio...