Biodistribution of 99m technetium- labeled creatinine in healthy rats

The distribution of creatinine, one of the toxic guanidine compounds, in various tissues has not been studied in detail by using radiolabeled creatinine. Our objective was to investigate the biodistribution of creatinine labeled with 99m technetium (99mTc) by the stannous (II) chloride method in healthy male Wistar rats. Quality controls were carried out by radio thin layer chromatography, high-performance liquid chromatography, and paper electrophoresis. The labeling yield was 85 ± 2 percent under optimum conditions (pH 7 and 100 æg stannous chloride). Rats (N = 12) were injected intravenously with 99mTc-creatinine and their blood and visceral organs were evaluated for 99mTc-creatinine uptake as percent of the injected dose per gram wet weight of each tissue ( percentID/g). The lowest amount of uptake was detected in the brain and testis. When the rate of uptake was evaluated, only the kidney showed increasing rates of uptake of 99mTc-creatinine throughout the study. Kidneys showed the highest amount of uptake throughout the study (P < 0.001 compared to all other organs), followed by liver, spleen and lung tissue.

New methodology for pancreatic scintiscanning imaging using 125I-L-3 iodo-alpha-methyl tyrosine

The difficulty of a reliable diagnosis of pancreatic diseases by scintiscanning, is mainly derived from the lack of adequate radiopharmaceuticals. With this purpose (125) I-L(-3) Iodo-a-Methyl Tyrosine ((125) I-IMT) has been studied, which has also been used for the diagnosis of different kind of brain tumors. The purpose of this work is the development of a quick and easy method for the synthesis and purification of the (125) I-IMT in order to be used in a Nuclear Medicine Service. The L-(-Methly Tyrosine was labeled with (125) I using I-/I03 and afterwards purified by an aniomic exchange resin. The labeling yield obtained was (96.0+0.5) per cent when the incubation time was 15 minutes. No significant statistical differences were observed when the incubation time was extended to 1 hour. Biodistribution studies in mice show that the percentage of activity concentration in pancreas is (34.24+14.03) per cent at 15 minutes post injection, remaining constant for 30 minutes. The pancreas/liver ratio 15 minutes after the injection of the labeled product was (12.22+3.59) and it remained constant for 45 minutes more. These results show that (125) I-IMT cab be used as a diagnostic agent for pancreatic diseases. Since (123) I was not avilable at the moment, this new methodology was developed with (125) I.

Aminoacidos urinarios: electroforesis por alto voltaje y acetato de celulosa gelatinizado / Urinary amino acids: electrophoresis for high voltage and in gelatinized cellulose acetate

El estudio de las alteraciones del metabolismo de los aminoacidos urinarios ha motivado el desarrollo de dos tecnicas simples, rapidas y economicas, para el uso en Quimica clinica. Se describe la celda electroforetica disenada, asi como todas las operaciones requeridas para lograr dicho objetivo (tratamiento de los soportes usados y de las muestras, buffers, condiciones de corrida, distintos metodos y reactivos de revelado, desintometria). Se comparan los resultados obtenidos para los soportes empleados, papel y acetato de celulosa gelatinizado, usando para ambos igual sistema de refrigeracion y los resultados obtenidos en comparacion con otra forma de enfriamiento del sistema, utilizada previamente. Tambien se discute la aplicacion de mayores voltajes y la importancia de la estandarizacion en la coloracion. Trabajando con acetato de celulosa gelatinizado se pueden valorar por densitometria las corridas, lo cual brinda una util herramienta a los laboratorios clinicos

Separaçäo de vitaminas pela eletroforese em papel / Separation of vitamins by paper electrophoresis

As vitaminas A (retino), B1 (tiamina), B6 (piridoxina), B12 (cianocobalamina), C (ácidoo ascórbico) e E (alfa-tocoferol), foram analisadas por eletroforese inidimensional em papel (qualitativo Klabin), usando como eletrólito soluçöes aquosas de carbonato de amônio 0,050, 0,075 e 0,100 M, sob um gradiente de potencial de 12,6V/cm. As melhores separaçöes ocorreram com o eletrólito nas concentraçöes 0,050 M (30 e 45 minutos) e 0,100 (45 e 60 minutos), quando 05 (cinco) vitaminas foram perfeitamente separadas: A (ou B6)-B1-B12-C e E

Separaçäo de antibióticos pela eletroforese em papel / Separation of antibiotics by papel electrophoresis

Os antibióticos fosfomicina, rifamicina, dicloxacilina penicilina G benzatina e gentamicina foram analisados por eletroforese unidimensional em papel (qualitativo Klabin), usando como eletrólito soluçöes aquosas de carbonato de amônio de concentraçöes 0,08, 0,10, 0,30 e 0,50 M, sob um gradiente de potencial de 12,6 V/cm. Todos os antibióticos citados apresentaram-se bem separados, utilizando o eletrólito nas concentraçöes 0,19 M (25 minutos) e 0,50 M (15 minutos)