Cytotoxicity, inflammation, biomineralization, and immunoexpression of IL-1β and TNF-α promoted by a new bioceramic cement

Abstract Aim To evaluate the cytotoxicity, biocompatibility and mineralization capacity of BIO-C PULPO, and MTA. Methodology L929 fibroblasts were cultured and MTT assay was used to determine the material cytotoxicity on 6, 24, and 48 h. A total of 30 male rats (Wistar) aged between 4 and 6 months, weighing between 250 and 300 g were used. Polyethylene tubes containing BIO-C PULPO, MTA, and empty tubes were implanted into dorsal connective tissue. After the experimental periods (7, 15, 30, 60, and 90 days) the tubes were histologically analyzed using hematoxylin-eosin (H&E), immunolabeling of IL-1β and TNF-α, and von Kossa staining, or without staining for polarized light analysis. The average number of inflammatory cells was quantified; the mineralization assessment was determined by the area marked in μm2 and semiquantitative immunolabeling analyses of IL-1β and TNF-α were performed. Then, data underwent statistical analysis with a 5% significance level. Results It was observed that BIO-C PULPO and MTA presented cytocompatibility at 6, 24, and 48 similar or higher than control for all evaluated period. On periods 7 and 15 days, BIO-C PULPO was the material with the highest number of inflammatory cells (p<0.05). On periods 30, 60, and 90 days, BIO-C PULPO and MTA presented similar inflammatory reactions (p>0.05). No statistical differences were found between Control, BIO-C PULPO, and MTA for immunolabeling of IL-1β and TNF-α in the different periods of analysis (p<0.05). Positive von Kossa staining and birefringent structures under polarized light were observed in all analyzed periods in contact with both materials, but larger mineralization area was found with BIO-C PULPO on day 90 (p<0.05). Conclusion BIO-C PULPO was biocompatible and induced mineralization similar to MTA.

Evaluation of the level of knowledge and compliance with standart precautions and the safety standard (NR-32) amongst physicians from a public university hospital, Brazil / Avaliacao do nivel de conhecimento e adesao as precaucoes-padrao e da Norma Regulamentadora (NR-32) entre os medicos de um hospital publico universitario, Brasil

Brazil is the first country in the world to have broad coverage standard (NR-32) focused on protecting health workers exposed to biological risks. This study evaluated the degree of knowledge of the NR-32 Standard and the level of knowledge and compliance with the standard precautions. A cross-sectional study was conducted with 208 randomly selected health professionals; 93 of them were residents and 115 were physicians at a Brazilian Clinical Hospital. To collect information, the participants were interviewed and/or they completed semi-structured questionnaires divided into three domains: knowledge of the standard, knowledge of biosafety, and compliance with standard precautions. Cronbach's alpha was used to assess internal consistency of the scales of knowledge and compliance with values above +0.75 indicating excellent agreement. Multivariate linear regression was used to evaluate the predictors for compliance with NR-32, biosafety, and standard precautions. Mean knowledge of the NR-32 Standard was 2.2 (± 2.02) points (minimum 0 and maximum 7 points). The minimum expected mean was 5.25 points. The mean knowledge of biosafety was 12.31 (± 2.10) points (minimum 4 and maximum16 points). The minimum expected mean was 12.75 points. The mean compliance with standard precautions was 12.79 (± 2.6) points (minimum 6 and maximum 18 points). The minimum expected mean was 13.5 points. The individual means for using gloves, masks and goggles during procedures and for not recapping needles were 2.69, 2.27, 1.20 and 2.14, respectively. The factors associated with knowledge of the NR-32 were: greater knowledge amongst those who studied at a public university and who had knowledge of biosafety. The knowledge of the NR-32 Standard was low, but there was a good level of knowledge of biosafety issues. The compliance with standard precautions was acceptable in general, but was low for some of the evaluated precautions.

O Brasil é o primeiro país do mundo a ter uma norma de ampla abrangência (NR-32) que enfatiza a proteção dos trabalhadores de saúde expostos a riscos biológicos. Este estudo avaliou o grau de conhecimento da Norma NR-32, o nível de conhecimento e adesão às precauções padrão. Estudo transversal foi realizado com 208 profissionais selecionados aleatoriamente, sendo 93 médicos residentes e 115 médicos, em um Hospital Universitario brasileiro. As informações foram coletadas mediante entrevista e/ou preenchimento de questionário semiestruturado dividido em três domínios: conhecimentos da norma, conhecimentos em biossegurança e adesão às precauções padrão. Para avaliar a consistência interna das escalas de conhecimento e adesão, utilizou-se o alfa de Cronbach, considerando-se concordância excelente para valores maiores que +0,75. Regressão linear multivariada foi utilizada para avaliar os fatores preditores da adesão à NR-32, biossegurança e precauções padrão. A média de conhecimento sobre a Norma NR-32 foi 2,2 (± 2,02) pontos (mínimo 0 e máximo 7 pontos,). A média mínima esperada foi de 5,25 pontos. A média de conhecimento em biossegurança foi de 12,31 (± 2,10) (mínimo 4 e máximo 16 pontos). Foi esperada uma média mínima de 12,75 pontos. A média de adesão às precauções padrão foi de 12,79 (± 2,6) pontos (mínimo 6 e máximo 18). A média mínima esperada foi de 13,5 pontos. A média individual para o uso de luvas, máscara e óculos durante procedimentos e o não reecape de objetos perfurocortantes foi de 2,69, 2,27, 1,20 e 2,14, respectivamente. Os fatores associados ao conhecimento da NR-32 foram: maior conhecimento para quem estudou em universidade pública e quem tem conhecimento sobre biossegurança. O conhecimento da Norma NR-32 foi baixo, mas o nível de conhecimento em temas de biossegurança foi bom. A adesão às precauções-padrão em geral foi aceitável, mas foi baixa para algumas precauções avaliadas.