Tamiko Ichikawa Ikeda

Teste in vitro de citotoxicidade: estudo comparativo entre duas metodologias

A avaliacao in vitro da biocompatibilidade de diferentes tipos de biomateriais foi realizada pelo teste de citotoxicidade em cultivo de celulas de tecido conectivo de camundongos, NCTC Clone 929 da American Type Culture Collection. O estudo comparativo do ensaio de citotoxicidade foi realizado com duas metodologias: 1) ensaio de difusao em agar e 2) ensaio de incorporacao do vermelho neutro. Os resultados obtidos demonstraram que ambas as metodologias podem ser utilizadas, de acordo com o tipo de amostra a ser analisada.

Cellulose acetate propionate coated titanium: characterization and biotechnological application

Surfaces of pure titanium and Ti coated with cellulose acetate propionate (CAP) have been characterized by means of scanning electron microscopy X ray coupled with elemental microanalysis (SEM-EDS), ellipsometry, atomic force microscopy (AFM) and contact angle measurements. Coating Ti surfaces with CAP ultrathin films reduced original surface roughness. Surface energy and wettability of CAP covered Ti surfaces pure Ti surfaces were similar. The adsorption of lysozyme (LYZ), an antibacterial protein, onto Ti and CAP-coated Ti surfaces has been studied by means of ellipsometry and atomic force microscopy (AFM). The adsorption of LYZ was mainly driven by hydrophobic interaction between protein hydrophobic residues and CAP propyl groups. Pure Ti and CAP coated Ti surfaces presented no cytotoxicity effect and proved to be adequate substrates for cell adhesion. The biocompatibility of CAP coated Ti surfaces was attributed to the surface enrichment in glucopyranosyl residues and short alkyl side groups.

O impacto do último enxágue na citotoxicidade de produtos críticos passíveis de processamento

Objective: To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method: This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results: No cytoxicity was detected in the sample extracts. Conclusion: The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.Objective To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results No cytoxicity was detected in the sample extracts. Conclusion The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.

Comparação de métodos para testar a citotoxicidade "in vitro" de materiais biocompatíveis

OBJECTIVE A comparison of the sensitivity of the agar diffusion method with that of extraction using cell-lines RC-IAL (fibroblastic of rabbit kidney) and HeLa (epithelial carcinoma cells from the cervix uteri of the human uterus), in the in vitro evaluation of materials of medical and hospital. MATERIALS AND METHODS Fifteen samples chosen at random, from among the already known positives and negatives in our stock, were tested and identified as cotton, form, latex, cellulose and acrylic. Besides the samples mentioned, many SDS (GIbco) concentrations were tested experimentally in RC-IAL and HeLa cell cultures. RESULTS Of the 50 samples tested, 44(88%) were positive by both methods. However, when the SDS were compared by using the two methods, positive results were noted in the concentrations of from 0.5 to 0.05 microgram/ml in the agar diffusion ans extraction methods. A cytotoxic effect was only noted in the concentrations of up to 0.25 microgram/ml. CONCLUSION When the SDS was used, differences favorable to the agar diffusion method were observed in the two cell lines, in two concentrations; that is, the sensitivity of this method was quantitatively greater on inspection than that of the extraction method, as well as being the simpler method to use.

Corrosion Performance and Cytotoxicity of Sintered Nd-Fe-B Magnets

In this investigation, the corrosion performance of a commercial sintered Nd-Fe-B magnet in a cell culture medium, and the cytotoxic response due to the magnet corrosion products leached into the cell culture medium, have been studied. Localized corrosion was observed and the corrosion products leached into cell culture medium were analyzed by ICP-OES. The magnet showed no toxicity in the neutral red uptake assay used in this investigation contradicting results from literature obtained by another method of cytotoxicity assay.

Impacto del último enjuague en la citotoxicidad de productos críticos pasibles de procesamiento

Objective: To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method: This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results: No cytoxicity was detected in the sample extracts. Conclusion: The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.Objective To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results No cytoxicity was detected in the sample extracts. Conclusion The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.

The impact of the final rinse on the cytoxicity of critical products submitted for processing

Objective: To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method: This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results: No cytoxicity was detected in the sample extracts. Conclusion: The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.Objective To assess the cytotoxicity of products subsequent to a cleaning process based on a validated standard operating procedure (SOP), and a final rinse with different types of water: tap, deionized, distilled, treated by reverse osmosis and ultra-purified. Method This was an experimental and laboratory study. The sample consisted of 130 hydrodissection cannulas, 26 per experimental group, characterized according to type of water used in the final rinse. The samples were submitted to internal and external contamination challenge with a solution containing 20% defibrinated sheep blood and 80% of sodium chloride 0.9%. Next, the lumens were filled with a ophthalmic viscosurgical device, remaining exposed for 50 minutes, and then were processed according to the validated SOP. Cytotoxicity was assessed using neutral red uptake assay. Results No cytoxicity was detected in the sample extracts. Conclusion The samples did not display signs of cytotoxicity, regardless of final rinse quality. The results obtained were reached by using only a validated cleaning operating procedure, based on the scientific literature, and on official recommendations and related regulation.

Cytotoxicity of PVC tubes sterilized in ethylene oxide after gamma radiation exposure

Los materiales esterilizados con rayos gama, al ser re-esterilizados en oxido de etileno (EO), ?forman substancias toxicas? Esta pregunta oriento el objetivo del presente estudio, que fue investigar el potencial efecto citotoxico del PVC esterilizado en radiacion gamma y re-esterilizado en EO por el metodo de difusion en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilizacion por radiacion gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de analisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyo en que los materiales de PVC esterilizados con Radiacion Gamma y, posteriormente, con EO, no son citotoxicos.Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to represent the internal and external surfaces and mass of each tube. It was concluded that the PVC materials sterilized in gamma radiation and re-sterilized in EO are not cytotoxic.

Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama

Los materiales esterilizados con rayos gama, al ser re-esterilizados en oxido de etileno (EO), ?forman substancias toxicas? Esta pregunta oriento el objetivo del presente estudio, que fue investigar el potencial efecto citotoxico del PVC esterilizado en radiacion gamma y re-esterilizado en EO por el metodo de difusion en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilizacion por radiacion gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de analisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyo en que los materiales de PVC esterilizados con Radiacion Gamma y, posteriormente, con EO, no son citotoxicos.Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to represent the internal and external surfaces and mass of each tube. It was concluded that the PVC materials sterilized in gamma radiation and re-sterilized in EO are not cytotoxic.

Citotoxicidad de tubos de PVC esterilizados en óxido de etileno luego de exposición a la radiación gamma

Los materiales esterilizados con rayos gama, al ser re-esterilizados en oxido de etileno (EO), ?forman substancias toxicas? Esta pregunta oriento el objetivo del presente estudio, que fue investigar el potencial efecto citotoxico del PVC esterilizado en radiacion gamma y re-esterilizado en EO por el metodo de difusion en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilizacion por radiacion gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de analisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyo en que los materiales de PVC esterilizados con Radiacion Gamma y, posteriormente, con EO, no son citotoxicos.Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to represent the internal and external surfaces and mass of each tube. It was concluded that the PVC materials sterilized in gamma radiation and re-sterilized in EO are not cytotoxic.