RESUMEN
The purpose of this investigation was to compare the efficiency of two different imaging protocols using two different clinically available 99mTc labelled myocardial perfusion tracers. One thousand one hundred and thirty-four imaging studies were performed prospectively, using either 99mTc-tetrofosmin or 99mTc-sestamibi, alternating the use of each tracer for a total period of 8 months. 99mTc-tetrofosmin rest studies were performed with injections of 259MBq-370MBq and imaging 30 min later. Exercise studies were performed with injections of 777MBq-1.11GBq and imaging 20 min later. 99mTc-sestamibi studies used doses similar to those in the 99mTc-tetrofosmin studies. Imaging followed a standard procedure, at 60 min after rest injection, and 30 min after exercise. For patients undergoing pharmacological stress testing99mTc-sestamibi was imaged 45 min after injection and 99mTc-tetrofosmin was imaged 30 min after injection. Variables analysed were (1) injection-to-imaging time for the procedure, and (2) the number of repeated scans because of extra cardiac activity. The completion time for the rest study was significantly shorter for 99mTc-tetrofosmin compared to 99mTc-sestamibi (47.7+/-21.7 min vs 74.3+/-25.8 min P<0.0001). Likewise, the total study time was shorter for 99mTc-tetrofosmin compared to 99mTc-sestamibi (90+/-32.7 min vs 124+/-37 min, P<0.0001). More importantly, the number of repeated scans was higher with 99mTc-sestamibi compared to 99mTc-tetrofosmin, 21.4% vs 10%, P=0.001 for rest studies and 16.4% vs 7.9% P=0.001 [corrected] for rest and stress. It was concluded that, using a same day rest/stress protocol, 99mTc-tetrofosmin provided higher patient throughput with fewer repeat scans. These factors may be considered for efficiency improvement in nuclear cardiology laboratories using 99mTc perfusion tracers.
Asunto(s)
Adenosina , Isquemia Miocárdica/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tecnecio Tc 99m Sestamibi , Prueba de Esfuerzo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/metabolismo , Compuestos Organofosforados/administración & dosificación , Compuestos Organofosforados/economía , Compuestos Organofosforados/farmacocinética , Compuestos de Organotecnecio/administración & dosificación , Compuestos de Organotecnecio/economía , Compuestos de Organotecnecio/farmacocinética , Estudios Prospectivos , Radiofármacos/administración & dosificación , Radiofármacos/economía , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tecnecio Tc 99m Sestamibi/administración & dosificación , Tecnecio Tc 99m Sestamibi/economía , Tecnecio Tc 99m Sestamibi/farmacocinética , Factores de Tiempo , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
RESUMO Este trabalho analisa o efeito larvicida do óleo Zingiber officinale Roscoe contra larvas em terceiro estágio do mosquito Aedes aegypti. Extraiu-se quantitativamente o óleo essencial por hidrodestilação e calculou-se a CL50 do óleo, a partir dos métodos de Reed-Muench e Pizzi, respectivamente. O óleo essencial obteve CL50 de 76,07 (±2,24) μg mL-1 e rendimento de 0,52% m/v. Os resultados indicam que o óleo essencial avaliado é composto por substâncias que propiciam efeito larvicida contra Aedes aegypti.
ABSTRACT This study analyzes the larvicidal effect of the oil of Zingiber officinale Roscoe against larvae in third stage of the mosquito Aedes aegypti (Linnaeus 1792). The essential oil was extracted quantitatively by hydrodistillation and we calculated the oil’s LC50 from Reed-Muench (1938) and Pizzi (1950) methods, respectively. The essential oil obtained LC50 of 76.07 (±2.24) ug mL-1, and yield of 0.52% m/v. The results indicate that the essential oil assessed has substances that provide larvicidal effect against Aedes aegypti.