Abstract The aim of this study was to incorporate tucuma oil (Astrocaryum vulgare) into PolyCaprolactone (PCL) electrospun fibers and evaluate its physicochemical properties and cell viability. FTIR and DRX confirmed that tucuma oil (TO) does not affect the chemical properties of PCL and that the oil was loaded into the PCL microstructure, while TGA analysis showed that the oil increased the thermal stability of the polymeric fibers. SEM showed that the addition of the oil modified fibers structure by reducing the average fiber size from 5.5 μm to 1.7 μm for TO loaded samples. Cell viability assay demonstrated an increment on cell proliferation from 80% of pure PCL to 100% for samples containing TO. Therefore, it can be concluded that tucuma oil can be incorporated into PCL to form fibers by electrospinning, without meaningful changes in its physicochemical properties and increasing its biocompatibility.

Resumo Introdução A quantidade e qualidade óssea na implantodontia é um fator de alta relevância quando se tem por objetivo instalar implantes e reabilitar pacientes. No entanto, essa disponibilidade é comprometida na maioria dos casos, havendo a necessidade da busca de novos biomateriais, membranas e substâncias para uma regeneração mais favorável. Objetivo: O objetivo deste estudo foi avaliar a resposta da neoformação óssea em defeitos críticos em calvárias de ratos utilizando scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico) e poli-isopreno (Cellprene®). O projeto foi aprovado pelo Comitê de Ética em Experimentação Animal. Material e método Neste estudo, foram utilizados 36 ratos (Rattus Norvegicus), variação albinus, Holtzman, adultos. Os animais foram submetidos à tricotomia na região da calota craniana e à confecção de defeitos ósseos circulares bilaterais com 5 mm de diâmetro. Os animais foram divididos em três grupos: GC – defeito sem colocação de biomaterial; GCol – scaffolds de colágeno (Bio-Gide, da empresa Geistlich Pharma Ag – Biomaterials); GPoli – scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico - Cellprene®). Cada grupo foi avaliado em quatro períodos experimentais (7, 15, 30 e 60 dias). Após esses períodos, os animais foram sacrificados, e as peças passaram por tramitação laboratorial de rotina e inclusão em parafina. Foram obtidos cortes semisseriados e corados pela técnica de hematoxilina e eosina para análise histométrica e histológica. Foi executada análise histométrica para avaliar a composição do tecido ósseo reparado (% osso). Os dados obtidos foram analisados estatisticamente com nível de significância de 95%. Resultado Foi verificado que o GCol apresentou maior preenchimento do defeito nos períodos de 30 e 60 dias em comparação aos GC e GPoli. Conclusão Os scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico) e poli-isopreno (Cellprene®) não apresentaram vantagens quando utilizados em defeitos críticos.

Abstract Introduction The bone quantity and quality in implant dentistry is a highly relevant factor when it aims the use of implants and rehabilitation in patients. However, this availability is compromised in most cases, with the need to research new biomaterials, membranes and substances for more favorable regeneration. Objective: The aim of this study was to evaluate the response of bone neoformation in critical defects in rat calvaries using polymeric blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid) and Polyisoprene (Cellprene®). The project was approved by the Animal Experimentation Ethics Committee. Material and method In this study 36 rats (Rattus Norvegicus), variation albinus, Holtzman, adults were used. The animals had trichotomy in the region of the skull and the confection of bilateral circular bone defects with a diameter of 5 mm. The animals were divided into 3 groups: Group GC - defect without biomaterial placement, Group GCol - collagen scaffolds (Bio-Gide, from Geistlich Pharma Ag - Biomaterials), Group GPoli - polymeric blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid)-Polyisoprene. Each group was evaluated in 4 experimental periods (7, 15, 30 and 60 days). After these periods the animals were sacrificed and the pieces underwent routine laboratory procedures and paraffin embedding. Semi-serial sections were obtained and stained by hematoxylin and eosin technique for histometric and histological analysis. Histometric analysis was performed to evaluate the composition of repaired bone tissue (% Bone). The data obtained were statistically analyzed with a significance level of 95%. Result It was found that the GCol group presented greater defect filling in the 30 and 60 days periods compared to the GC and GPoli groups. Conclusion Polymer blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid) and Polyisoprene (Cellprene®) did not have advantages when used in critical defects.

Abstract Objectives This study aimed to evaluate the potential of adipose-derived stem cells (ASCs) combined with a modified α-tricalcium phosphate (α-TCP) or gelatin sponge (GS) scaffolds for bone healing in a rat model. Material and Methods Bone defects were surgically created in the femur of adult SHR rats and filled with the scaffolds, empty or combined with ASCs. The results were analyzed by histology and histomorphometry on days seven, 14, 30, and 60. Results Significantly increased bone repair was observed on days seven and 60 in animals treated with α-TCP/ASCs, and on day 14 in the group treated with GS/ASCs, when compared with the groups treated with the biomaterials alone. Intense fibroplasia was observed in the group treated with GS alone, on days 14 and 30. Conclusions Our results showed that the use of ASCs combined with α-TCP or GS scaffolds resulted in increased bone repair. The higher efficacy of the α-TCP scaffold suggests osteoconductive property that results in a biological support to the cells, whereas the GS scaffold functions just as a carrier. These results confirm the potential of ASCs in accelerating bone repair in in vivo experimental rat models. These results suggest a new alternative for treating bone defects.

Abstract One of the most important characteristics of calcium phosphate cements is their resorbability when implanted in the body. However, the in vivo resorption rate is slow due to the lack of intrinsic open porosity. In this study, macroporous structures were obtained by mixing alpha-tricalcium phosphate (α-TCP) cement with a foamed liquid phase containing different concentrations of sodium hydrogen phosphate and non-ionic (Lutensol) or anionic (Sodium Lauryl Sulfate) surfactant. The cement paste was prepared by hand mixing in a system of two syringes connected by a polyvinyl chloride (PVC) valve, an environmentally friendly method. Solutions with Lutensol (L110) showed greater foamability than solutions with Sodium Lauryl Sulfate (SLS). Scanning Electron Microscopy characterization helped verify that the prepared samples showed a macroporous interconnected structure, and X-ray diffraction analysis evidenced the transformation of α-TCP into calcium deficient hydroxyapatite (CDHA). This study suggests that the calcium phosphate cement samples foamed with Lutensol may be further evaluated as suitable materials for bone filling.

Current treatments of craniosynostosis rely on the application of metal springs for cranial bone deviation. However, those metal springs demand a second surgical procedure for their removal. An attractive alternative would be the substitution of metal for bioresorbable polymers in the composition of the springs. The addition of poly(isoprene), PI, to poly(lactic-co-glycolic acid), PLGA, produces a polymeric blend with partial miscibility and distinct mechanical behavior that may benefit the patient recover. It is necessary to compare the histotoxicity of PLGA/PI to that presented by PLGA. In order to verify the histological behavior of the blend, 46 male Wistar rats (Rattus norvegicus, albino strain) underwent implantation of PLGA or PLGA/PI in the skull and were allocated into subgroups by timing of euthanasia (15, 30, 60, or 90 days). After euthanasia, the skull was removed and the histotoxicity was assessed histopathologically. The PLGA/PI blend showed greater histotoxicity in animals euthanized at 60 days, although in this period the histotoxicity of the PLGA/PI blend was similar to that of the PLGA copolymer at 15 days. Despite the instability of histological response, presented in different periods of observation, the results obtained in long-term show that the material has high potential for studies in craniosynostosis treatment.

The application of renewable raw materials encourages research in the biopolymers area. The Poly(Lactic-co-Glycolic Acid)/Poly(Isoprene) (PLGA/IR) blend combines biocompatibility for application in the health field with excellent mechanical properties. The blend was obtained by solubilization of polymers in organic solvents. To investigate the polymer thermochemical properties, FTIR and DSC were applied. To investigate the composition's influence over polymer mechanical properties, tensile and hardness test were applied. To analyze the blends response in the cell environment, a stent was produced by injection molding process, and Cell Viability Test and Previous Implantability were used. The Infrared spectra show that chemical composition is related only with polymers proportion in the blend. The calorimetry shows a partial miscibility in the blend. The tensile test shows that adding Poly(Isoprene) to Poly(Lactic-co-Glycolic Acid) induced a relevant reduction in the Young modulus, tensile stress and tenacity of the material, which was altered from the fragile raw PLGA to a ductile material. The composition did not affect the blend hardness. The cell viability test shows that the blend has potential application as biomaterial, while the first results of implantability indicate that the polymeric stent kept its original position and caused low fibrosis.

OBJETIVO: Este estudo avaliou o desempenho hemodinâmico e as alterações miocárdicas decorrentes do emprego de dispositivos de assistência ventricular esquerda (DAVE), associado ou não à descompressão do ventrículo direito por meio de derivação cavo-pulmonar, sendo esses achados comparados ao emprego de assistência circulatória biventricular. MÉTODOS: Vinte e um suínos foram submetidos à indução de insuficiência cardíaca através de fibrilação ventricular, sendo a atividade circulatória mantida por DAVE durante 180 minutos. No grupo controle, foi apenas implantado o DAVE. No grupo derivação, além do DAVE foi realizada cirurgia de derivação cavo-pulmonar. No grupo biventricular, foi instituída assistência biventricular. Foram monitoradas as pressões intracavitárias por 3 horas de assistência e amostras do endocárdio dos dois ventrículos foram coletadas e analisadas à microscopia óptica e eletrônica. RESULTADOS: O lactato sérico foi significativamente menor no grupo biventricular (P=0,014). A diferença observada entre o fluxo do DAVE nos grupos derivação e controle (+55±14 ml/kg/min, P=0,072) não foi significativa, enquanto que o fluxo no grupo biventricular foi significativamente maior (+93±17 ml/kg/min, P=0,012) e se manteve estável durante o experimento. A pressão arterial média (PAM) se manteve constante apenas no grupo biventricular (P<0,001), que também apresentou diminuição significativa das pressões em câmaras direitas. Na análise ultraestrutural, notou-se menor presença edema miocárdico no ventrículo direito no grupo biventricular (P=0,017). CONCLUSÃO: Os resultados apresentados demonstram que o desempenho hemodinâmico da assistência ventricular esquerda associada à derivação cavo-pulmonar, neste modelo experimental, não foi superior ao observado com a assistência de ventrículo esquerdo isolada e não substituiu a assistência biventricular de maneira efetiva.

OBJECTIVE: Right ventricular (RV) failure during left ventricular assist device (LVAD) support can result in severe hemodynamic compromise with high mortality. This study investigated the acute effects of cavo-pulmonary anastomosis on LVAD performance and RV myocardial compromise in comparison with biventricular circulatory support, in a model of biventricular failure. METHODS: LVAD support was performed by centrifugal pump in 21 pigs with severe biventricular failure obtained by FV induction. Animals were randomized to be submitted to cavo-pulmonary anastomosis, to biventricular circulatory support or to control group. They were maintained under circulatory support and hemodynamic monitoring for 3h. Venous lactate and cytokines serum levels were also obtained. Endocardium samples were analyzed by electronic microscopy. RESULTS: FV maintenance was responsible for acute LVAD impairment after 180 min in the control group. cavo-pulmonary anastomosis resulted in non-significant improvement of LVAD pump flow in relation to control group (+55±14 ml/kg/min, P=0.072), while animals under biventricular support maintained higher LVAD flow (+93±17 ml/kg/min, P=0.012). Mean arterial pressure remained constant only in biventricular group (P<0.001), which also presented decrease of right atrial and ventricular pressures. Similar increases in lactate and cytokines levels were observed in the three groups. Ultra-structural analysis documented low levels of myocardial swelling in the biventricular group (P=0.017). CONCLUSION: The concomitant use of cavo-pulmonary anastomosis during LVAD support in a pig model of severe biventricular failure resulted in non-significant improvement of hemodynamic performance and it did not effectively replace the use of biventricular support.

The addition of tricalcium silicate (C3S) to apatite cements results in an increase of bioactivity and improvement in the mechanical properties. However, adding large amounts raises the local pH at early stages, which retards the precipitation of hydroxyapatite and produces a loss of mechanical strength. The introduction of Pozzolanic materials in cement pastes could be an effective way to reduces basicity and enhance their mechanical resistance; thus, the effect of adding silica on the chemical, mechanical and biological properties of α-tricalcium phosphate/C3S cement was studied. Adding silica produces a reduction in the early pH and a decrease in setting times; nevertheless, the presence of more calcium silicate hydrate (C-S-H) delays the growth of hydroxyapatite crystals and consequently, reduces early compressive strength. The new formulations show a good bioactivity, but higher cytotoxicity than traditional cements and additions higher than 2.5% of SiO2 cause a lack of mechanical strength and an elevated degradability.

OBJETIVO: Avaliar a capacidade da mistura de α-TCP e osso autógeno (OA) Vs somente α-TCP e somente OA em promover a neoformação óssea e reparo tecidual em defeitos ósseos. MÉTODOS: Foram criados cirurgicamente defeitos ósseos em 15 ratos Wistar machos, distribuídos em quatro grupos: Grupo I (OA), Grupo II (α-TCP), Grupo III (α-TCP + OA avaliado por microscopia de luz) e Grupo IV (α-TCP + OA avaliado por microscopia eletrônica de varredura). Os resultados da reparação óssea foram avaliados em 30, 60 e 120 dias. RESULTADOS:os achados histológicos obtidos nos grupos I (p = 0,459), II (p = 0,368) e III (p = 0,459) e aos 30 dias (p = 0,717), 60 dias (p = 0,717), e 120 dias (p = 0,779) não apresentaram diferenças estatisticamente significativas. A análise por microscopia eletrônica de varredura revelou contacto direto entre o implante de α-TCP + AO e o tecido ósseo aos 120 dias. CONCLUSÃO: O implante de α-TCP é alternativa eficaz como substitutos ósseos para o tratamento de defeitos ósseos de tamanho crítico.

PURPOSE: To evaluate the ability of a mixture of α-TCP and autogenous bone (AB) vs. α-TCP alone and AB alone to promote new bone formation and tissue repair in bone defects. METHODS: Bone defects surgically created in 15 male Wistar rats were divided into four groups: Group I (AB), Group II (α-TCP), Group III (α-TCP+AB assessed by light microscopy), and Group IV (α-TCP+AB assessed by scanning electron microscopy). Bone repair findings were assessed at 30, 60, and 120 days postoperatively. RESULTS: The histological findings obtained in Groups I (p=0.459), II (p=0.368), and III (p=0.459) and at 30 days (p=0.717), 60 days (p=0.717), and 120 days (p=0.779) did not show statistically significant differences. Scanning electron microscopy revealed direct contact between the α-TCP+AB implant and the bone tissue at 120 days. CONCLUSION: The α-TCP implant is effective alternative bone substitutes for the treatment of critical size bone defects.

Objetivo: Avaliar a capacidade de suportes tridimensionais macroporosos de cimento de fosfato de cálcio (CFC), de permitir a adesão, proliferação e diferenciação de células-tronco mesenquimais derivadas da medula óssea humana. Métodos: células obtidas da crista ilíaca de um doador humano adulto foram processadas e cultivadas sobre suportes de CFC, macroporosos, que tiveram como corpo gerador de poros, microesferas de parafina, com tamanho entre 100 e 250µm. Os períodos de cultura estabelecidos foram de cinco, 10 e 15 dias. Após estes períodos, o comportamento e a morfologia das células junto ao biomaterial foram avaliados por meio de Microscopia Eletrônica de Varredura. Os níveis de expressão dos genes BGLA e SSP1 bem como a atividade da Fosfatase Alcalina (ALP) foram quantificados pela técnica de PCR em Tempo Real (QT-PCR) utilizando o fluoróforo SYBR Green®. Resultados: O QT-PCR detectou a expressão dos genes BGLA e SSP1 e a atividade da fosfatase alcalina nos períodos de 10 e 15 dias de cultura. No período de cinco dias, não foi observada a expressão de nenhum dos genes investigados. Conclusão: O CFC, macroporoso, com tamanho de poros entre 100 e 250µm, criados por meio da utilização de microesferas de parafina, permite a adesão, proliferação e diferenciação de células-tronco mesenquimais em células osteogênicas, podendo ser utilizado como arcabouço para engenharia de tecido ósseo.

Purpose: To evaluate the ability of macroporous tricalcium phosphate cement (CPC) scaffolds to enable the adhesion, proliferation, and differentiation of mesenchymal stem cells derived from human bone marrow. Methods: Cells from the iliac crest of an adult human donor were processed and cultured on macroporous CPC discs. Paraffin spheres sized between 100 and 250µm were used as porogens. Cells were cultured for 5, 10, and 15 days. Next, we assessed cells' behavior and morphology on the biomaterial by scanning electron microscopy. The expression levels of the BGLA and SSP1 genes and the alkaline phosphatase (ALP) activity were quantified by the quantitative real-time polymerase chain reaction technique (QT-PCR) using the fluorophore SYBR GREEN®. Results: QT-PCR detected the expression of the BGLA and SSP1 genes and the ALP activity in the periods of 10 and 15 days of culture. Thus, we found out that there was cell proliferation and differentiation in osteogenic cells. Conclusion: Macroporous CPC, with pore sized between 100 and 250µm and developed using paraffin spheres, enables adhesion, proliferation, and differentiation of mesenchymal stem cells in osteogenic cells and can be used as a scaffold for bone tissue engineering.

Os cimentos de fosfatos de cálcio são biomateriais formados pela mistura de um pó de fosfato de cálcio com água ou com solução aquosa de sais orgânicos ou inorgânicos formando uma pasta que reage à temperatura ambiente ou corpórea, endurecendo como resultado da reação de precipitação. Cimentos de fosfato de cálcio são usados comumente em cirurgias de preenchimento ósseo na odontologia e ortopedia, que requerem procedimentos extremamente invasivos. A inovação consiste em formular uma pasta injetável pela incorporação de aditivos. Neste estudo, três aditivos (carboxi-metil-celulose, polímero de agar e alginato de sódio) foram incorporados a fosfato tricálcico-alfa, nas concentrações de 0,4%; 0,8%; 1,6%; 3,2%; 6,4% em massa. Os resultados demonstraram que foi possível obter composições de cimento de fosfato tricálcico injetáveis. Verificou-se que a injetabilidade, medida por um método inédito proposto, depende do comportamento reológico das pastas. Neste estudo, as formulações com 1,6% de carboxi-metil-celulose, 1,6% de agar e 0,8% de alginato de sódio, permitiram a obtenção de uma viscosidade suficiente para uma boa homogeneização e injeção do cimento.

Calcium phosphate cements are biomaterials made of a mixture of calcium phosphate powder with water or with aqueous solutions of inorganic or organic salts, forming a paste that reacts at room or body temperature and hardens as a result of precipitation reactions. Calcium phosphate cements are commonly used in both dentistry and orthopedic bone filling surgeries, which require extremely invasive procedures. The innovation consists in formulate an injectable paste by incorporation of additives. In this work, three different additives (carboxymethylcellulose, agar polymer and calcium alginate) were incorporated in alpha-tricalcium phosphate (alpha-TCP), in concentrations of 0.4%; 0.8%; 1.6%; 3.2% and 6.4% wt%. Results showed that it was possible to obtain injectable compositions of tricalcium phosphate cement. It was verified that the injectability, measured by a novel method, depends on the rheological behavior of the pastes and injection time. In this study, pastes with sufficient viscosity for good homogenization and injection were obtained. In this study, pastes with 1.6% carboxymethylcellulose, 1.6% agar and 0.8% sodium alginate present sufficient viscosity for good homogenization for cement injection.

OBJETIVO: A artéria radial (AR) tem sido largamente empregada na revascularização do miocárdio (RM), porém a diferença da anastomose proximal na aorta ou em enxerto composto com a artéria torácica interna esquerda (ATIE) ainda é controversa. Avaliamos os resultados clínicos imediatos do uso da artéria radial (AR) anastomosada proximalmente na aorta ou como enxerto composto em "Y" com a ATIE. MÉTODO: Cem pacientes foram randomizados e submetidos à RM no Hospital Beneficência Portuguesa de São Paulo, no período de novembro de 1999 a março de 2001. Nos pacientes do Grupo I (GI), a AR foi anastomosada proximalmente na aorta e, nos pacientes do Grupo II (GII), a AR foi anastomosada na ATIE. A veia safena (VS) autógena foi usada quando necessário. RESULTADOS: Os grupos I e II mostraram-se homogêneos quanto às características pré-operatórias. A mortalidade imediata total foi de 1,0% (GI 2,0% e GII 0,0%) - p =1,00. O número de artérias coronárias anastomosadas por paciente foi de 3,0+0,12, no GI e de 2,82+0,12, no GII (p=0,29). Os pacientes do GII apresentaram tempo de circulação extracorpórea (CEC) menor do que do GI (p=0,0001). Não houve diferença significativa entre as outras variáveis peri-operatórias estudadas. CONCLUSÃO: Os pacientes apresentaram resultados clínicos semelhantes quando a AR foi anastomosada proximalmente na aorta ou como enxerto composto em "Y" na ATIE, e a anastomose proximal na ATIE não aumenta os riscos de complicações imediatas.

OBJECTIVE: The clinical results of the radial artery when proximally anastomosed to the aorta or to the left internal thoracic artery (LITA) as a composite Y-graft were comparatively evaluated. METHODS: From November 1999 to March 2001, 100 patients who underwent coronary artery bypass grafting using the RA, the LITA and, when required, the saphenous vein, were divided in two groups with 50 patients each in a prospective randomized study. Group I (GI) with radial artery proximally anastomosed to the aorta and Group II (GII) as a composite graft (Y-graft) with the LITA. RESULTS: Early mortality was 1.0 % (GI 2.0% and GII 0.0%) (p=1.00). A mean of 3.0+0.12 (GI) versus 2.82+0.12 (GII) (p=0.29) coronary vessels were grafted per patient. Patients in composite Y-graft group had shorter bypass time (p=0.0001). There were no differences in terms of perioperative outcomes. CONCLUSIONS: The RA provides similar clinical results as aorto-coronary grafts and ascomposite Y-grafts with the LITA, except in respect to the bypass time.

O espasmo de artéria coronária (EAC) pode ocorrer como uma grave complicação na revascularização do miocárdio (RM), no período intra e pós-operatório imediato. O pequeno número de casos relatados na literatura dificulta o tratamento adequado e reconhecimento dos fatores que possam desencadear essa complicação. O EAC tem caráter multifatorial, aparecimento súbito e deve entrar no diagnóstico diferencial como causa de infarto agudo do miocárdio (IAM) e síndrome de baixo débito em pacientes submetidos às cirurgias cardíacas. Apresentamos o caso de um paciente submetido à cirurgia de RM com circulação extracorpórea que apresentou alteração eletrocardiográfica sugestiva de IAM, no pós-operatório imediato, quando foi realizado cateterismo cardíaco que demonstrou EAC. O paciente foi tratado com sucesso com vasodilatadores intracoronarianos e teve boa evolução a curto e médio prazo.

Coronary artery spasms may occur as a serious complication during the trans-operative and immediate postoperative periods of coronary artery bypass surgery (CABS). The small number of cases reported is responsible for making it difficult not only to choose an adequate treatment but also to determine risk factors that might be responsible for its incidence. Coronary artery spasms have a multifactorial character, sudden appearance and must be part of the differential diagnosis of acute myocardial infarction and low output syndrome among patients submitted to heart surgery. We describe a case of a patient submitted to CABS with extracorporeal circulation who presented electrocardiographic alterations suggesting acute myocardial infarction during the immediate postoperative period but was diagnosed as having coronary artery spasms evidenced by a coronary catheterism performed afterwards. The patient was successfully treated with intracoronary vasodilators with good evolution over the short and medium terms.

Aneurisma de arco aórtico com fístula aorto-pulmonar aguda é uma afecção rara e, geralmente, diagnosticada postmortem. Poucos relatos de sucesso cirúrgico foram realizados e persiste uma alta taxa de mortalidade. Os autores relatam o caso de um paciente de 78 anos, com comunicação aguda entre aneurisma de arco aórtico e artéria pulmonar com precordialgia, instabilidade hemodinâmica e congestão pulmonar. A operação foi realizada com sucesso, sendo realizada a substituição da porção proximal da aorta descendente, do arco aórtico e da porção distal da aorta ascendente, além do fechamento da fístula.

Aortic arch aneurysm associated with an acute aorto-pulmonary fistula is rare and usually diagnosis is made during the postmortem. Few reports of successful surgical management have been reported and a high mortality rate remains. The authors report on a 78-year-old male patient with an acute aortic arch aneurysm communicating with the main pulmonary artery suffering from cardiac chest pain, hemodynamic instability and lung congestion. The patient underwent surgery to replace the distal ascending aorta, transverse aortic arch and proximal descending aorta as well as fistula closure. The operation was successful.

OBJETIVO: Avaliar a biocompatibilidade do cimento de fosfato de cálcio, para verificar sua eficácia como possível substituto ósseo. MÉTODOS: No presente trabalho, foi utilizado cimento de fosfato de cálcio em rádio de 8 coelhos, separados em dois grupos (GI e GII), referentes aos tempos de observação de 12 e 26 semanas pós-operatórias, a fim de se observar as reações entre este biomaterial e o tecido ósseo do animal. Foram feitas análises radiográficas e de densitometria óptica, além de microscopia óptica e eletrônica de varredura. RESULTADOS: Observou-se, ao final do experimento, que o cimento à base de fosfato de cálcio foi parcialmente reabsorvido durante o tempo de observação de 26 semanas, apresentando biocompatibilidade, com ausência de reações indesejáveis que pudessem ser atribuídas aos implantes. CONCLUSÕES: O cimento à base de fosfato de cálcio foi biocompatível e parcialmente reabsorvido no período de 26 semanas de observação. Tempos maiores de observação são necessários para a avaliação da reabsorção.

PURPOSE: The objective of this paper was to evaluate the biocompatibility of calcium phosphate cement in radius of rabbits. METHODS: For this experiment, calcium phosphate were implanted in the radius of 16 rabbits, divided in two groups (GI and GII), according to postoperative follow-up of 12 and 26 weeks, respectively. Reactions of these biomaterials on animal bone tissue were observed. X-ray, optical densitometry, optical microscopy and scanning electron microscopy analyses were performed. RESULTS: It was observed that calcium phosphate cement were partially resorbed during the 26-week follow-up, showing biocompatibility, with absence of inflammatory or other undesirable reactions due to the implants. CONCLUSIONS: Calcium phosphate-based cements did not cause inflammatory reactions when in contact with the osseous tissue, and were therefore biocompatible. Follow-up periods longer than 26 weeks are necessary to better evaluate the behavior of calcium phosphate-based cement.