Aeração de dispositivos médicos esterilizados a óxido de etileno: considerações acerca da regulação brasileira / Aecization of medical devices sterilized to ethylene oxide: considerations about Brazilian regulation / Aireación de dispositivos médicos esterilizados con óxido de etileno: consideraciones sobre la regulación brasileña

Objetivos: Descrever níveis residuais aceitáveis de óxido de etileno em dispositivos médicos, analisar processos de aeração recomendados e compará-los com a regulação brasileira. Método: Revisão integrativa da literatura, com descritores específicos, sem restrição de ano de publicação. Busca dos dados entre outubro e novembro de 2019, que resultou em 34 estudos incluídos no estudo. Resultados: A regulação brasileira vigente está desatualizada em relação à classificação de produtos, à determinação de valores de resíduos tóxicos de óxido de etileno em dispositivos médicos e aos processos recomendados para a aeração desses produtos, podendo contribuir para riscos de eventos adversos para pacientes usuários de dispositivos inadequadamente aerados, e, consequentemente, urge sua atualização. Conclusão: As lacunas desse marco regulatório beneficiam indiretamente as empresas que terceirizam a esterilização a óxido de etileno ao omitir controles essenciais para a segurança do paciente exposto a possíveis resíduos tóxicos de óxido de etileno, favorecer práticas inseguras de esterilização de produtos para saúde, além de dificultar o controle de serviço de saúde pelas vigilâncias sanitárias do país.

Objectives: To describe acceptable residual levels of ethylene oxide in medical devices, analyze recommended aesther processes and compare them with the Brazilian regulation. Method: Integrative literature review, with specific descriptors, without year of publication restriction. Data search between October and November 2019, which resulted in 34 studies included in the study. Results: Current Brazilian regulation is outdated in relation to product classification, the determination of waste values ethylene oxide toxic in medical devices and the recommended processes for the aecization of these products, and may contribute to risks of adverse events for patients users of inappropriately aenated devices, and consequently urge their update. Conclusion: The shortcomings of this regulatory framework indirectly benefit companies that outsource ethylene oxide sterilization by omitting essential controls for safety of the patient exposed to possible toxic residues of ethylene oxide, unsafe practices of sterilization of health products, in addition to hindering the control of health service by the country's health surveillance.

Objetivos: Describir los niveles residuales aceptables de óxido de etileno (OE) en dispositivos médicos, analizar los procesos de aireación recomendados y compararlos con la normativa brasileña. Método: revisión integrativa de la literatura, con descriptores específicos, sin restricción de año de publicación. Búsqueda de datos entre octubre y noviembre de 2019, que resultó en 34 estudios incluidos en el estudio. Resultados: La normativa brasileña actual está desactualizada en cuanto a la clasificación de productos, determinación y valores de residuos tóxicos de OE en dispositivos médicos y procesos recomendados para la aireación de estos productos, lo que puede contribuir al riesgo de eventos adversos para los pacientes que utilizan una aireación inadecuada de dispositivos y, en consecuencia, se necesita urgentemente una actualización. Conclusión: Las brechas en este marco regulatorio benefician indirectamente a las empresas que externalizan la esterilización a OE, al omitir controles esenciales para la seguridad de los pacientes expuestos a posibles residuos tóxicos de OE, favoreciendo prácticas inseguras de esterilización de productos sanitarios, además de dificultar el control de servicio de salud por la Vigilancia Sanitaria del país.

Source Analysis of Ethylene Oxide Sterilization Residues in Medical Devices / 中国医疗器械杂志

At present, the most commonly used sterilization method for medical devices is ethylene oxide sterilization. The residue after sterilization is closely related to the health of the people who contacted with the medical devices. The study team analyzed the possible residues of medical devices after sterilization with ethyleneoxide. It is suggested that ethylene oxide, 2-chloroethanol and ethylene glycol should be evaluated comprehensively through the analysis of factors such as production links of medical devices, production process of ethylene oxide, sterilization process, sterilization environment and detection method.

Physicochemical and Tissue Response of PLA Nanofiber Scaffolds Sterilized by Different Techniques / Evaluación fisicoquímica y respuesta tisular de andamios nanofibrilares de PLA esterilizados por diferentes técnicas

ABSTRACT In recent years, tissue engineering has evolved considerably, due to the problems in the biomedical area concerning tissue regeneration therapies. Currently, work has been focused on the synthesis and physicochemical characterization of poly lactic acid scaffolds, a synthetic polyester that has been extensively study for its excellent biocompatibility and biodegradability. Moreover, sterilization strategies of scaffold are a crucial step for its application in tissue regeneration, however, the sterilization process have to maintain the structural and biochemical properties of the scaffold. Therefore, it is very important to carry out studies on the sterilization methods of the sample's material, since translational medicine is intended for in vivo applications. The aim of the present study was designed to analyze the effects of different sterilization techniques, i.e. ethylene oxide (ETO), gamma radiation (GR) and hydrogen peroxide- based plasma (H2O2) in biodegradable PLA scaffolds, and to determine the best sterilization technique to render a sterile product with minimal degradation and deformation, and good tissue response. Analysis of surface morphology showed that ETO and GR modified the PLA scaffolds without any change in its chemical composition. Moreover, the histological response showed that the scaffolds are biocompatible and those sterilized by GR showed a more severe inflammatory response, accompanied with the presence of giant foreign body cells. In conclusion, the results show that among sterilization techniques used in the preset study, the best results were observed with H2O2 sterilization, since it did not significantly modify the surface structure of the PLA fibers and their in vivo response did not cause an unfavorable tissue reaction.

RESUMEN En los últimos años, la ingeniería de tejidos ha evolucionado considerablemente, debido a las incógnitas en las terapias de regeneración en el área biomédica. Actualmente, se ha trabajado en la síntesis y caracterización fisicoquímica de andamios de poliácido láctico, el cual es un polímero sintético que se ha estudiado para aplicaciones en ingeniería de tejidos, debido a su biocompatibilidad y biodegradabilidad. El proceso de esterilización es un paso crucial en la aplicación de andamios en terapias de regeneración, sin embargo, la técnica de esterilización debe mantener las propiedades estructurales y bioquímicas del andamio. Por lo tanto, es muy importante realizar estudios sobre los métodos de esterilización de dichos andamios, ya que la medicina traslacional está diseñada para aplicaciones in vivo. El objetivo del presente estudio fue analizar los efectos de diferentes técnicas de esterilización como óxido de etileno (ETO), radiación gamma (GR) y plasma a base de peróxido de hidrógeno (H2O2) en andamios biodegradables de PLA, y determinar la mejor técnica de esterilización con mínima degradación y deformación, así como una respuesta tisular favorable. La estructura de la superficie de los andamios de PLA se modificó principalmente con las técnicas de óxido de etileno y radiación gamma, sin embargo, ninguna técnica modificó su composición química. Con la respuesta histológica se demostró que los andamios de PLA son biocompatibles y que los esterilizados por radiación gamma desencadenan una mayor respuesta inflamatoria y la formación de células gigantes de cuerpo extraño. En conclusión, los resultados muestran que las técnicas de esterilización utilizadas pueden modificar la morfología del andamio, sin embargo; los mejores resultados se observaron con la esterilización por plasma a base de peróxido de hidrógeno, ya que no modificó significativamente la estructura de la superficie de las fibras de PLA y su respuesta in vivo no provocó una reacción desfavorable en el tejido.

In Vitro Study Evaluating the Antimicrobial Activity of Vancomycin-Impregnated Cement Stored at Room Temperature in Methicillin-Resistant Staphylococcus aureus / 대한족부족관절학회지

PURPOSE: Treatment of diabetic foot infection due to methicillin-resistant Staphylococcus aureus (MRSA) remains challenging. Applying vancomycin-impregnated cement is one of the best methods of treatment. Vancomycin-impregnated cement has been used worldwide; however, to date, there is a limited number of studies regarding its use. We evaluated the duration of antimicrobial activity of vancomycin-impregnated cement stored at room temperature after manufacturing. MATERIALS AND METHODS: The vancomycin-impregnated cement was manufactured by mixing 1 g of vancomycin with 40 g of polymer and adding 17.90 g of liquid monomer. The cement dough was shaped into flat cylinders with diameter and height of 6 mm and 2 mm, respectively. Another cement of the same shape without mixing vancomycin was prepared as the negative control. All manufactured cements were sterilized with ethylene oxide gas and stored at room temperature. Each cement was placed on Mueller Hinton agar plate lawned with standard MRSA strain. Standard vancomycin disk and gentamicin disk were placed together. After 24 hours, the diameter of inhibition zone was measured, and if the diameter was less than 15 mm, vancomycin-impregnated cement was regarded as a loss of antimicrobial activity. The study was repeated every 2 weeks until vancomycin-impregnated cements lost their antimicrobial activity. RESULTS: Vancomycin-impregnated cement stored for a duration of 16 weeks created a 14 mm inhibition zone, while vancomycin disk created a 15 mm inhibition zone. Vancomycin-impregnated cement stored for a duration of 17 weeks created 7 mm and 9 mm inhibition zones, while vancomycin disk created 16 mm and 15 mm inhibition zones, respectively. CONCLUSION: We found a decrease of antimicrobial activity in vancomycin-impregnated cements after 16 weeks. After 17 weeks, they showed definite loss of antimicrobial activity. Therefore, we recommend not using vancomycin-impregnated cement spacers that has been stored for more than 16 weeks at room temperature.

Nova proposta para o tratamento da Leishmaniose tegumentar usando antimoniato de meglumina e oxiranos em associação / New proposal for the treatment of cutaneous leishmaniasis using meglumine antimoniate and oxirans in combination

Esta tese porpõe uma nova abordagem para o tratamento da leishmaniose tegumentar com o antimoniato de N-metilglucamina (antimoniato de meglumina - AM) associado a dois derivados oxiranos. O estudo foi conduzido em modelo murino de infecção in vitro e in vivo por Leishmania (Leishmania) amazonensis. Na primeira etapa do estudo foram descritas alterações histológicas causadas por epoxi-α-lapachona, epoximetil-lausona e AM em camundongos BALB/c não infectados, bem como a predição de algumas de suas propriedades farmacocinéticas. Os resultados indicaram que tanto os oxiranos quanto o antimoniato de meglumina induzem alterações histopatológicas nos órgãos analisados. O epoximetil-lausona foi o mais tóxico para o tecido pulmonar, enquanto os danos mais graves no coração foram causados pelo epoxi-α-lapachona. O AM causou alterações leves a moderadas nos tecidos cardíacos e pulmonares, mas sem qualquer efeito detectado nos tecidos cerebrais. Na segunda etapa foi necessário avaliar a eficácia do epoximetil-lausona sobre a infecção de macrófagos e camundongos BALB/c infectados por L.(L.) amazonensis. Em amastigotas intracelulares, o IC50 do epoximetil-lausona foi ligeiramente superior ao do AM (7,41 ± 0,2 e 4,43 ± 0,25 µM, respectivamente), sendo o efeito mais evidente após 48 horas de exposição (18 vezes e 7,4 vezes inferiores, respectivamente).

Os promastigotas também foram afetados pelo composto, porém o IC50 foi seis vezes maior (45,45 ± 5,0µM), indicando sua especificidade sobre os amastigotas intracelulares. A análise de citotoxicidade revelou que o epoximetil-lausona tem um efeito menor (1,7 ×) comparado ao AM (40,05 ± 3,0 e 24,14 ± 2,6 µM). O tratamento com três doses do epoximetil-lausona reduziu a lesão da pata dos animais infectados em 27 %, enquanto a redução obtida com o AM chegou a 31% nas doses baixa e intermediária, e 64% com a dose mais alta, comparado ao grupo controle. Alterações ultraestruturais detectadas nos amastigotas da lesão constataram comprometimento da integridade dos parasitos. Na etapa final deste estudo foi demonstrado o efeito do tratamento com o AM associado aos oxiranos epoxi-α-lapachona e epoximetil-lausona sobre a infecção experimental in vitro e in vivo. Os compostos foram testados individualmente e em combinações, seguindo as razões: 3:1; 1:1 e 1:3 (p/v) sobre macrófagos infectados. Todos os compostos, assim como suas combinações mostraram índices endocíticos muito inferiores ao grupo controle, sendo as maiores reduções obtidas nas razões de 3:1. O tratamento de camundongos BALB/c com os compostos individualmente e combinados nas mesmas razões levou a reduções significativas das lesões. O melhor efeito das combinações foi observado nas razões de 3:1. Os resultados indicaram que a associação do AM com os oxiranos produz um incremento no efeito leishmanicida, e pode ser considerada uma nova abordagem para o tratamento da leishmaniose cutânea. (AU)

Comparison of apical extrusion of intracanal bacteria by various glide-path establishing systems: an in vitro study

OBJECTIVES: This study compared the amount of apically extruded bacteria during the glide-path preparation by using multi-file and single-file glide-path establishing nickel-titanium (NiTi) rotary systems. MATERIALS AND METHODS: Sixty mandibular first molar teeth were used to prepare the test apparatus. They were decoronated, blocked into glass vials, sterilized in ethylene oxide gas, infected with a pure culture of Enterococcus faecalis, randomly assigned to 5 experimental groups, and then prepared using manual stainless-steel files (group KF) and glide-path establishing NiTi rotary files (group PF with PathFiles, group GF with G-Files, group PG with ProGlider, and group OG with One G). At the end of canal preparation, 0.01 mL NaCl solution was taken from the experimental vials. The suspension was plated on brain heart infusion agar and colonies of bacteria were counted, and the results were given as number of colony-forming units (CFU). RESULTS: The manual instrumentation technique tested in group KF extruded the highest number of bacteria compared to the other 4 groups (p < 0.05). The 4 groups using rotary glide-path establishing instruments extruded similar amounts of bacteria. CONCLUSIONS: All glide-path establishment instrument systems tested caused a measurable apical extrusion of bacteria. The manual glide-path preparation showed the highest number of bacteria extruded compared to the other NiTi glide-path establishing instruments.

Reversible Cerebral Vasoconstriction Syndrome Complicated with Cerebral Infarct after Inhaling Ethylene Oxide Gas

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by thunderclap headache and multiple reversible intracranial vasoconstrictions. Here we report a case of RCVS after exposure to ethylene oxide (EO) gas, which is a widely used sterilant. A 34-year-old woman presented with aphasia, right-arm weakness, and severe headache after inhaling EO gas. Brain imaging revealed multiple infarcts and multiple intracranial stenoses. The stenotic lesions completely regressed on follow-up CT angiography. This is the first report of RCVS after exposure to EO gas.

A Study on Expiration Date on Ethylene Oxide Gas Sterilization Products: Related to Storage Environment / 기본간호학회지

PURPOSE: This was a study on the expiration date of Ethylene Oxide (EO) gas sterilization and effects of the environmental factors of temperature, humidity and type of cabinet in sterile goods storage area on the expiration date. METHODS: Sterile goods storage areas from 13 departments in one hospital were selected and 455 EO gas sterilization samples were prepared and kept in those areas over the 14 months of the study. Each sample was tested with a microbiological culture in the laboratory every week. If the result was positive, the sample was regarded as contaminated. The researcher visited once a month to check the temperature, humidity and type of cabinet. RESULTS: With the exception of 1 sample which was positive at 56th week. 454 samples were confirmed as negative. The environment of the samples storage area was measured monthly. The annual average temperature was 24.2+/-1.6degrees C, and the mean relative humidity 34.7+/-15.2%. The types of cabinet were 7 open and 6 closed. CONCLUSION: The results of the microbiological culture at 13 months showed that none of the samples were contaminated. Therefore the hospital's existing Expiration Date can be extended from 6 months to 13~14 months.

Discussion about the sampling positions of the bag-type infusion sets for single use in the ethylene oxide residues detection / 中国医疗器械杂志

This paper selects the bag-type infusion sets for single use as samples, which are produced by different manufacturers and based on the ethylene oxide sterilization. The ethylene oxide sterilization residues in different parts of samples are detected by colorimetric analysis. Combined the comparison of the ethylene oxide residues testing results in the different parts of the same sample with the actual situation in clinical use, more reasonable sampling positions are found to detect the ethylene oxide sterilization residues. The result of this experiment will play a guiding role in the detection of the actual samples.

Effects of reprocessing on chemical and morphological properties of guide wires used in angioplasty / Efeitos do reprocessamento nas propriedades químicas e morfológicas de fios-guia usados em angioplastia

OBJECTIVE: To investigate the influence of the reprocessing technique of enzymatic bath with ultrasonic cleaning and ethylene oxide sterilization on the chemical properties and morphological structure of polymeric coatings of guide wire for regular guiding catheter. METHODS: These techniques simulated the routine of guide wire reprocessing in many hemodynamic services in Brazil and other countries. Samples from three different manufacturers were verified by scanning electron microscopy and X-ray photoelectron spectroscopy. RESULTS: A single or double sterilization of the catheters with ethylene oxide was not associated with morphological or chemical changes. However, scanning electron microscopy images showed that the washing method was associated with rough morphological changes, including superficial holes and bubbles, in addition to chemical changes of external atomic layers of polymeric coating surfaces, as detected by the X-ray photoelectron spectroscopy method, which is compatible with extended chemical changes on catheter surfaces. CONCLUSION: The reprocessing of the catheters with ethylene oxide was not associated with morphological or chemical changes, and it seemed appropriate to maintain guide wire coating integrity. However, the method combining chemical cleaning with mechanical vibration resulted in rough anatomical and chemical surface deterioration, suggesting that this reprocessing method should be discouraged.

OBJETIVO: Investigar a influência das técnicas de reprocessamento de banho enzimático com limpeza ultrassônica e a esterilização com óxido de etileno nas propriedades químicas e estruturas morfológicas de revestimentos poliméricos de fios-guia usados como guias em cateteres regulares. MÉTODOS: Estas técnicas simulam a rotina de processamento de fios-guia em muitos serviços de hemodinâmica do Brasil e de outros países. Amostras de três diferentes fabricantes foram verificadas por microscopia eletrônica de varredura e espectroscopia de fotoelétrons de raios-X. RESULTADOS: Uma única ou dupla esterilização dos cateteres com óxido de etileno não foi associada a mudanças químicas ou morfológicas. Contudo, imagens de microscopia eletrônica de varredura mostraram que o método de lavagem foi associado a intensas modificações morfológicas, incluindo bolhas e buracos superficiais, assim como mudanças nas ligações químicas das camadas atômicas externas do revestimento polimérico, conforme demonstrado por resultados de espectroscopia de fotoelétrons de raios-X, compatível com extensas modificações químicas induzidas por esse processo de lavagem. CONCLUSÃO: O reprocessamento dos fios-guia de cateteres com óxido de etileno não está associado a mudanças químicas e morfológicas dos mesmos e pode ser considerado adequado para manter a integridade destes materiais. Entretanto, o método que combina lavagem química com vibração mecânica resulta em intensas deteriorações anatômicas e químicas, sugerindo que esse método de processamento deve ser desencorajado.

Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama / Cytotoxicity of PVC tubes sterilized in ethylene oxide after gamma radiation exposure / Citotoxicidad de tubos de PVC esterilizados en óxido de etileno luego de exposición a la radiación gamma

Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO), formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos.

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.

Los materiales esterilizados con rayos gama, al ser re-esterilizados en óxido de etileno (EO), ¿forman substancias tóxicas? Esta pregunta orientó el objetivo del presente estudio, que fue investigar el potencial efecto citotóxico del PVC esterilizado en radiación gamma y re-esterilizado en EO por el método de difusión en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilización por radiación gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de análisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyó en que los materiales de PVC esterilizados con Radiación Gamma y, posteriormente, con EO, no son citotóxicos.

The importance of protecting surgical instrument tables from intraoperative contamination in clean surgeries / Importância da proteção da mesa de instrumentais cirúrgicos na contaminação intraoperatória de cirurgias limpas / Importancia de la protección de la mesa de instrumentos quirúrgicos en la contaminación intraoperatoria de cirugías limpias

OBJECTIVE: to compare the degree of bacterial contamination of surgical instrument tables used in clean surgical procedures, either protected with plastic fields, sterilized with ethylene oxide, or disinfected with 70% alcohol and 1% iodine solutions. This is a randomized clinical trial in which samples were collected from the surfaces of surgical instrument tables before and after each procedure. Microbiological analysis was performed to identify microorganisms and their respective antimicrobial resistance. RESULTS: Bacterial growth in the surgeries using sterilized plastic was 5.71% before and 28.6% after surgery and, 2.9% and 45.7% respectively in surgeries using disinfection with 70% alcohol and 1% iodine solutions; no statistical difference was found between the methods. CONCLUSION: both methods present similar protection, however, 70% alcohol and 1% iodine do not generate solid waste.

OBJETIVO: analisar o grau de contaminação bacteriana da mesa de instrumentais cirúrgicos, após o uso de campo plástico esterilizado por óxido de etileno ou a desinfecção com solução de álcool a 70% e iodo a 1%, em procedimentos cirúrgicos limpos. MÉTODOS: Trata-se de experimento clínico randomizado, com coletas de amostras das superfícies das mesas de instrumentais cirúrgicos, antes e depois de cada procedimento, com posterior análise microbiológica para identificação dos microrganismos e sua resistência antimicrobiana. RESULTADOS: nas cirurgias em que o plástico esterilizado foi utilizado, o crescimento bacteriano foi de 5,71% antes e 28,6% após a cirurgia, enquanto que nas desinfecções com solução de álcool a 70% e iodo a 1%, o crescimento foi de 2,9% antes e 45,7% após, sem diferença significativa entre os métodos empregados. CONCLUSÕES: os dois métodos têm poder de proteção semelhante, considerando que o álcool a 70% e iodo a 1% não geram resíduos sólidos.

El objetivo del estudio fue analizar el grado de contaminación bacteriana de la mesa de instrumentos quirúrgicos en dos casos, después del uso: cubierta protectora plástico de la mesa quirúrgica esterilizada con óxido de etileno o desinfección con solución de alcohol a 70% y yodo a 1%, en procedimientos quirúrgicos limpios. Se trata de un experimento clínico aleatorio, con recolección de muestras de las superficies de las mesas de instrumentos quirúrgicos, antes y después de cada procedimiento, con posterior análisis microbiológica para identificar los microorganismos y la resistencia antimicrobiana. En las cirugías en que el plástico esterilizado fue utilizado, el crecimiento bacteriano fue de 5,71% antes y 28,6% después de la cirugía, en cuanto que en las desinfecciones con solución de alcohol a 70% y yodo a 1%, el crecimiento fue de 2,9% antes y 45,7% después, lo que indica que no hubo diferencia significativa entre los métodos empleados. Los dos métodos tienen poder de protección semejante, considerando que el alcohol a 70% y yodo a 1% no generan residuos sólidos.

Comparative study and histomorphometric analysis of bone allografts lyophilized and sterilized by autoclaving, gamma irradiation and ethylene oxide in rats

PURPOSE: To compare three sterilization methods (autoclave, gamma irradiation and ethylene oxide) over non demineralized lyophilized bone allografts. METHODS: Bone allografts were implanted on paravertebral muscles of 21 rats. After 30 days animals were sacrificed and grafts underwent comparative analysis regarding histomorphometric and macroscopic parameters. RESULTS: Allografts that underwent the three sterilization methods presents similar weight gain, cortical thickness similar to control group, and less fibrosis than the control group. Grafts that underwent sterilization in autoclave presented less presence of multinucleated giant cells, although not statistically significant. There was also no statistically significant difference regarding mineralization on the three groups. CONCLUSION: The three sterilization methods cause similar effects on bone allografts regarding macroscopic and histomorphometric parameters.

Feasibility study on EO/EG wastewater treatment using pilot scale SBR

The sequencing batch reactors were developed to treat the actual wastewater from ethylene glycol/ethylene oxide producing industry. Four identical reactors with total and effective liquid volumes of 9 and 7 L were operated respectively in parallel. Laboratory experiments were conducted with different organic loadings of 500, 1000, 1500 and 3000 g-COD/m[3]. day and the performance of the reactors was studied under different sludge ages of 10, 20 and 30 days, the kinetic constants at optimal operational conditions were also determined. According to the results, the efficient removal of COD was 79.5 and 83.5% [SRT = 20 days] and 86% [SRT = 30 days] for SBR 1 and 2 respectively [OLR = 0.5 to 1 kg-COD/m[3]. day] with required reaction time of about 17 h. In order to reach the COD removal efficiencies over 86% at higher OLR values, the researchers required longer reaction periods about 34.5 h for SBR 3 and 4. However, the SRT values have no significant effects on the performance of SBR 1 and 2 at the aeration times greater than 22.5 h while in the case of reactors 3 and 4, with an increase on SRT at all aeration times, the COD removal efficiency increased. It is concluded that the system used in the present study could show an acceptable stability and performance in the treatment of the wastewater containing high concentrations of organic matters especially from EO/EG industries

Tejido óseo esponjoso esterilizado con gas óxido de etileno / Spongy bone tissue sterilized with ethylene oxide gas / Tissu osseux spongieux stérilisé à l'oxyde d'éthylène gazeux

Objetivo: comprobar las propiedades esterilizantes del gas óxido de etileno sobre el hueso esponjoso empleado como implante en la clínica médica, fundamentalmente su eficacia para determinados microorganismos y el tiempo necesario de su uso en autoclave industrial. Métodos: se prepararon 54 porciones de tejido óseo esponjoso en forma de cubo separados en 3 grupos de 18 porciones cada uno. El primer grupo se empleó para evaluar un método de contaminación bacteriológica con cepas de microorganismos conocidos. El segundo y tercer grupo una vez contaminados con los microorganismos conocidos se sometieron a la acción del gas óxido de etileno en subgrupos de 6, durante 60, 90 y 120 min. Resultados: en el primer grupo el 100 % de las muestras contaminadas se presentaron positivas. En los grupos segundo y tercero la efectividad del gas óxido de etileno resultó de 100 % a los 120 min. Conclusión: este método es seguro, por lo que es apropiado para el empleo en la clínica médica.

Objective: verify the sterilizing properties of ethylene oxide gas over the spongy bone used for implants in medical practice, mainly its efficacy against certain microorganisms and the time required for sterilization in industrial autoclaves. Methods: 54 cube-shaped spongy bone tissue samples were prepared and distributed into 3 groups, each with 18 samples. The first group was used to evaluate a bacteriological contamination method with strains of known microorganisms. Upon contamination with the known microorganisms, the second and third groups were subjected to the effect of ethylene oxide gas in subgroups of 6 samples during 60, 90 and 120 minutes. Results: in the first group 100 % of the samples contaminated were positive. In the second and third groups, the effectiveness of ethylene oxide gas was 100 % at 120 minutes. Conclusion: this is a safe method appropriate for use in medical practice.

Objectif: confirmer les propriétés stérilisantes de l'oxyde d'éthylène gazeux sur l'os spongieux utilisé comme implant dans la clinique médicale, notamment son efficacité contre certains microorganismes, et le temps nécessaire pour l'utiliser dans un autoclave industriel. Méthodes: cinquante-et-quatre portions de tissu osseux spongieux ont été préparées sous forme de cube, et séparées en 3 groupes de dix-huit portions chacun. Le premier groupe a été utilisé pour évaluer une méthode de contamination bactériologique à souches de microorganismes connus. Une fois contaminés par des microorganismes connus, les deuxième et troisième groupes ont été soumis à l'action de l'oxyde d'éthylène gazeux en sous-groupes de 6 au cours de 60, 90 et 120 minutes. Résultats: dans le premier groupe, 100 % des échantillons contaminés ont été positifs. Dans les deuxième et troisième groupes, l'efficacité de ce gaz a réussi 100 % à 120 minutes. Conclusion: cette méthode est sure, donc appropriée, pour la clinique médicale.

Apósito biológico esterilizado con gas óxido de etileno / A biological dressing sterilized using ethylene oxide gas

Objetivo: se presentó el resultado de una investigación preclínica dirigida a comprobar el poder esterilizante del gas óxido de etileno sobre la piel porcina empleada como apósito biológico. Métodos: se contaminaron 2 grupos de 60 muestras cada uno, de piel porcina liofilizada con una cepa de estafilococo coagulasa positivo y Pseudomona aeruginosa, respectivamente. El 25 por ciento de las muestras de cada grupo se envió al laboratorio de microbiología para comprobar la efectividad del método de contaminación. El 75 por ciento restante se trató durante diferentes períodos en una cámara de gas óxido de etileno y, posteriormente, se enviaron al laboratorio de microbiología para comprobar el grado de esterilidad. Resultados: se demostró la alta efectividad del gas óxido de etileno para esterilizar la piel porcina que es empleada como apósito biológico. Conclusiones: este método es seguro, por lo que es apropiado para el empleo en la clínica médica

Objective: to present the result from a preclinical research aimed to verify the sterilizing power of ethylene oxide gas on the porcine skin used as a biological dressing. Methods: two groups of 60 samples each of lyophilized porcine skin were contaminated with a strain of positive-coagulase staphylococcus and Pseudomona aeruginosa, respectively. The 25 percent of samples of each group was sent to microbiology laboratory to verify the effectiveness of contamination method. The remainder 75 percent was treated in different periods in a chamber of ethylene oxide gas and later, was sent to the above laboratory to verify the sterility degree. Results: it was demonstrated the effectiveness of the ethylene oxide gas to sterilize the porcine skin, which is used as a biological dressing. Conclusions: this method is safe, therefore it is appropriate to use in the medical clinic

Risk Factors for Breast Cancer, Including Occupational Exposures

The knowledge on the etiology of breast cancer has advanced substantially in recent years, and several etiological factors are now firmly established. However, very few new discoveries have been made in relation to occupational risk factors. The International Agency for Research on Cancer has evaluated over 900 different exposures or agents to-date to determine whether they are carcinogenic to humans. These evaluations are published as a series of Monographs (www.iarc.fr). For breast cancer the following substances have been classified as "carcinogenic to humans" (Group 1): alcoholic beverages, exposure to diethylstilbestrol, estrogen-progestogen contraceptives, estrogen-progestogen hormone replacement therapy and exposure to X-radiation and gamma-radiation (in special populations such as atomic bomb survivors, medical patients, and in-utero exposure). Ethylene oxide is also classified as a Group 1 carcinogen, although the evidence for carcinogenicity in epidemiologic studies, and specifically for the human breast, is limited. The classification "probably carcinogenic to humans" (Group 2A) includes estrogen hormone replacement therapy, tobacco smoking, and shift work involving circadian disruption, including work as a flight attendant. If the association between shift work and breast cancer, the most common female cancer, is confirmed, shift work could become the leading cause of occupational cancer in women.

Esterilización por baja temperatura y sus aplicabilidades / Low temperature sterilization and its applicabilities

Los métodos de esterilización a baja temperatura son muy utilizados, actualmente, para la esterilización de los materiales termosensibles. Este articulo es una revisión bibliográfica que tiene el objetivo de identificar, en la literatura científica, las evidencias de la actividad antimicrobiana, toxicidad, eventos adversos y laaplicabilidad de las tecnologias de esterilización a baja temperatura. La búsqueda de los articulos, fue realizada por medio de la consulta a la base de datos Medline y Google Académico, desde el año 2006 hata octubre de 2009. Para la búsqueda de los articulos, se utilizaron palabras controladas en el idioma inglés y el operador AND para la especificidad del tema que se queria consultar. Fueron leídos y analizados quince articulos en sus totalidades, cuyos los resultados son: (1) El proceso de esterelización por plasma presentó resultados positivos mediante el proceso de esterilización por óxido de etileno; (2) Hay pérdidas en las propriedades en reprocesamiento de catéter de hemodinámica; (3) Falta de reglamentación y seguridad para el reprocesamiento de los materiales de un solo uso; (4) El óxido de etileno no es eficiente en la esterilización de superficies óseas

The Clinical Significance of Reuse Disposable Instruments for Laparoscopic Surgery / 대한내시경복강경외과학회지

PURPOSE: Laparoscopic instruments have been remarkably developed through many trials. Various studies and experiments on laparoscopic instruments are underway in other countries. Laparoscopic surgery is also very actively applied in Korea. However, research on the use and safety of the instruments is stagnant. Furthermore, reuse of some disposable laparoscopic instruments is frequently observed, but there are only rare studies on the safety of this. Thus, we tried to provide study cases on the safety of repeated use of disposable laparoscopic instruments. METHODS: To investigate the effectiveness of sterilization and a re-package procedure, we divided the laparoscopic instruments that are commonly used in our institution into 10 types. Among all the available instruments, 32 instruments were selected for the simulation experiment. Each instrument was sterilized using ethylene oxide gas or glutaraldehyde 2%, and then packaged. Then, each was observed grossly and microscopically under aseptic conditions and we looked for any remnant foreign body or contaminant. When remnant foreign body or contaminant was found, they were collected and separately cultured. RESULTS: Residual contaminants were found in 15 instruments (46.9%) out of a total of 32 and microorganisms, including coagulase-negative staphylococcus and gamma-hemolytic streptococcus, were cultured from (9.38%), and each had different types of microorganisms. CONCLUSION: It is remarkable that the bacteria were cultured from recycled laparoscopic instruments after sterilization. The reuse of laparoscopic instruments might be cost-effective, but further studies on its safety are required. Moreover, careful inspection on the method of surgical instrument sterilization in each institution will be necessary.

Cases Series of Malignant Lymphohematopoietic Disorder in Korean Semiconductor Industry

OBJECTIVES: Seven cases of malignant lymphohematopoietic (LHP) disorder were claimed to have developed from occupational exposure at two plants of a semiconductor company from 2007 to 2010. This study evaluated the possibility of exposure to carcinogenic agents for the cases. METHODS: Clinical courses were reviewed with assessing possible exposure to carcinogenic agents related to LHP cancers. Chemicals used at six major semiconductor companies in Korea were reviewed. Airborne monitoring for chemicals, including benzene, was conducted and the ionizing radiation dose was measured from 2008 to 2010. RESULTS: The latency of seven cases (five leukemiae, a Non-Hodgkin's lymphoma, and an aplastic anemia) ranged from 16 months to 15 years and 5 months. Most chemical measurements were at levels of less than 10% of the Korean Occupational Exposure Limit value. No carcinogens related to LHP cancers were used or detected. Complete-shielded radiation-generating devices were used, but the ionizing radiation doses were 0.20-0.22 uSv/hr (background level: 0.21 microSv/hr). Airborne benzene was detected at 0.31 ppb when the detection limit was lowered as low as possible. Ethylene oxide and formaldehyde were not found in the cases' processes, while these two were determined to be among the 263 chemicals in the list that was used at the six semiconductor companies at levels lower than 0.1%. Exposures occurring before 2002 could not be assessed because of the lack of information. CONCLUSION: Considering the possibility of exposure to carcinogenic agents, we could not find any convincing evidence for occupational exposure in all investigated cases. However, further study is needed because the semiconductor industry is a newly developing one.