Stability tests and action limits setting for central frequency and transmitter gain of MRI scanners / 中国医学影像技术

Objective To test the central frequency (CF) and transmitter gain(TG) of MRI scanners,and set up their action limits.Methods Three different MRI devices (GE 3.0T HD,GE 1.5T HDi and GE 3.0T 750W) were tested by scanning American College of Radiology (ACR) phantom with the axial T1WI series.In the pre-scanning of T1WI series for the ACR phantom,the CF and TG were recorded.It was tested for eight times when MRI scanners were in good condition.The action limits of CF and TG were calculated based on mean values and standard deviations.Results The mean values of CF for three devices were (127 725 772.38±39.68)Hz,(63 875 740.13± 34.15)Hz,and (127 771 958.38±12.19)Hz,respectively.Their action limits were ≤119.04 Hz,≤68.30 Hz,and ≤36.57 Hz,respectively.The mean values of TG for three devices were (125.25±1.28)dB,(101.75±1.98)dB,and (113.25±0.89)dB,respectively.Their action limits were (125.25±2.56)dB,(101.75±3.96)dB,and (113.25±1.78)dB,respectively.Conclusion The CF and TG for three MRI scanners are all consistent with the action limits in this study.The CF and TG action limits will provide criterions for the clinical quality control.

Establecimiento de límites microbiológicos internos para áreas clasificadas Grado D / Establishing internal microbiological limits for D grade-classified areas

Objetivo: contribuir al aseguramiento de la calidad microbiológica de una planta de producción de vacunas, a través del establecimiento de límites internos de alerta y de acción para sus áreas clasificadas Grado D. Métodos: se estudió la microbiota residente de cada área clasificada Grado D. Se analizaron muestras de aire tomadas por el método volumétrico. Las superficies e indumentaria del personal fueron evaluadas por el método de contacto. Los recuentos de microorganismos fueron analizados estadísticamente para la determinación de los límites de alerta y de acción. Resultados: se establecieron los límites de alerta y de acción microbiológicos para cada área clasificada Grado D de la planta de producción del Instituto Nacional de Enfermedades Virales Humanas basados en la determinación de los rangos habituales de trabajo. Se establecieron límites, como en el caso de guantes pos trabajo para un área Grado D, donde la norma no los define. Conclusiones: se mostró concordancia con los límites recomendados por la autoridad regulatoria nacional ANMAT y proporcionó información sobre la carga microbiológica de los ambientes clasificados Grado D, que será de utilidad tanto para la comprensión del ingreso y circulación de microorganismos como para la implementación de medidas para prevenir la contaminación microbiana, aspectos críticos en la fabricación de vacunas seguras, puras y eficaces(AU)

Objective: to contribute to ensuring the microbiological quality of a vaccine manufacturing plant through the establishment of internal microbiological alert and action limits for their grade D classified areas. Methods: the resident microbiota of each grade D classified area was studied. Air samples taken by the volumetric method were analyzed. The surfaces and the staff's gowning were evaluated by the contact method. The microorganism counts were statistically analyzed to determine the alert and action limits. Results: the microbiological alert and action limits have been established for each Grade D classified area of the production plant of the National Institute of Human Viral Diseases, based on the determination of the usual working ranges. Limits were set, as in the case of gloves after work for a Grade D area, where the standard does not define them. Conclusions: the results generally agreed with the limits recommended by the national regulatory authority ANMAT, and additionally, this study provided information on the microbiological flora of grade D classified environments, which will be useful for both understanding the entrance and circulation of microorganisms and implementing measures to prevent biocontamination, which are critical aspects in the manufacture of effective, pure and safe vaccines(AU)

Microbiological monitoring of clean rooms in development of vaccines

The aim of the present work was to evaluate an environmental monitoring program for clean rooms, or classified environments, involved in the filling and quality control of biological products produced by Butantan Institute, São Paulo, Brazil. This monitoring established the quantification, characterization and seasonality of the microorganisms in air and operators and, moreover, determined the alert and action limits. The total detectable microbial number showed some contrasts in installed air purification systems and in the operational impact on adopted procedures. The typical microbial population consisted of Staphylococcus sp, Micrococcus sp, Bacillus sp and Penicillium sp. The highest microorganism concentration occurred during summer and springtime. The established internal alert and action limits supported the operational procedures. Therefore, the environmental monitoring program is recommended for other laboratories involved in the production of vaccines, hyperimmune sera and biopharmaceuticals.

O presente trabalho teve por objetivo avaliar um programa de monitoramento microbiológico ambiental para áreas limpas, ou ambientes classificados, envolvidas na produção, envasamento e controle dos imunobiológicos produzidos pelo Instituto Butantan. Este monitoramento permitiu a quantificação, a caracterização e a sazonalidade da população microbiana presente no ar e nos operadores, e a determinação dos limites de alerta e ação. O número total de bactérias detectáveis revelou diferenças nos sistemas de purificação de ar instalados e o impacto operacional ocasionado pelos procedimentos realizados. A população microbiana característica foi composta por bactérias dos gêneros Staphylococcus sp, Micrococcus sp, Bacillus sp e por fungos filamentosos do gênero Penicillium sp. A maior concentração de microrganismos ocorreu nos períodos de verão e primavera. Os limites internos de alerta e ação estabelecidos asseguram os procedimentos operacionais, recomendando o monitoramento microbiológico ambiental a outros laboratórios envolvidos na produção de vacinas, soros hiperimunes e imunobiológicos.