[Visualization of deep lung lymphatic network using radioliposomes]. / Visualização da rede linfática pulmonar profunda usando radioliposomas.

Deep lymphatic drainage plays an important role in the lung, as it removes foreign materials laying on the airways surface, such as pathogenic microorganisms. This drainage is also associated with lung tumour dissemination route. Liposomes with a specially tailored membrane were used as foreign particles to be removed by the lung lymphatics. We aim to obtain images of deep lung lymphatics in baboons using liposomes encapsulating (99m)Tc-HMPAO, as aerosols. Axillary lymph nodes were visualized 30 min post-inhalation, becoming more evident 1 hour after, when abdominal aortic and inguinal lymph nodes were also observed. Late images added no additional information. ROI's and their time-activity curves were drawn to obtain biokinetic information. In conclusion, we can say that the proposed technique enables visualization of the deep lymphatic lung network and lymph nodes. This methodology may be an important tool for targeted lung delivery of cytotoxic drugs.

[A new method for quantification of hepatobiliary scintigraphy using 99mTc-mebrofenin. A comparative study]. / Un nuevo método para la cuantificación de grammagrafía hepatobiliar utilizando 99mTcmebrofenina. Un estudio de comparación.

A method based upon the application of mathematical techniques of deconvolution on the classical compartmental model for the quantitative study of liver function from hepatobiliary scintigraphy using 99mTc-mebrofenin data is proposed. The theory in which the method is based upon is presented and a comparison with a published methodology of obtaining the hepatic extraction after scintigraphic sudies has been performed using the results on 36 rats studies obtained with the two methods. A highly significant correlation between the two techniques was verified. The characteristics of the two methodologies, the proposed one based upon a theoretical approach and the other one on an empirical approximation are discussed. Comments are made on the interest and limitations of the presented technique that may be an useful tool for the evaluation of hepatic insufficiency.

Un nuevo método para la cuantificación de grammagrafía hepatobiliar utilizando 99mtc-mebrofenina. Un estudio de comparación / A new method for quantification of hepatobiliary scintigraphy using 99mTc-mebrofenin. A comparative study

Se propone un método basado en la aplicación de técnicas matemáticas de deconvolución sobre el modelo compartimental clásico para el estudio cuantitativo de la función hepática con datos de gammagrafía hepatobiliar con 99mTc-mebrofenina. Se presenta la teoría sobre la cual se basa el método y se hace una comparación con una metodología publicada para la obtención de la extracción hepática después de hacer estudios grammagráficos utilizando los resultados de 36 estudios en ratas, obtenidos con los dos métodos. Se comprobó una correlación altamente significativa entre las dos técnicas. Se discuten las características de las dos metodologías, la propuesta basada en un enfoque teórico y la otra en un enfoque empírico. Se comenta el interés y limitaciones de la técnica presentada que puede ser una herramienta útil para la evaluación de la insuficiencia hepática. (AU)

(153)Sm(3+) and (111)In(3+) DTPA derivatives with high hepatic specificity: in vivo and in vitro studies.

Two DTPA derivatives, a mono-amide derivative containing an iodinated synthon, DTPA-IOPsp (L(1)) and the ligand DTPA(BOM)(3) (BOM=benzyloxymethyl) (L(2)), radiolabelled with (153)Sm(3+) and (111)In(3+), were studied as potential hepatospecific gamma scintigraphic agents. In vivo studies with Wistar rats show that the main excretory pathway for all the chelates studied is the hepatobiliary system. The complexes of L(2) show even greater hepatobiliary specificity than L(1), perhaps as a consequence of longer blood circulation times due to their strong affinity towards HSA. The (153)Sm(3+) chelates are also more hepatospecific than the corresponding (111)In(3+) chelates. The La(3+) and In(3+) chelates of L(1) and L(2) show some structural and dynamic differences in aqueous solution, as studied by (1)H NMR spectroscopy. While only two nona-coordinated isomers were observed for the La(3+) complexes with both ligands, its number is much larger in the In(3+) complexes, with both octa- and hepta-coordinated species (with unbound side arms), as well as structural isomers for each coordination number.