MIN 14C UBT: a combination of gastric basal transit and 14C-urea breath test for the detection of Helicobacter pylori infection in human beings.

The purpose of this work is to demonstrate that the 14C-urea breath test (UBT) performed at different times combined with the study of the gastric basal transit, which evaluates the intragastric displacement of a labeled solution under fasting conditions, has the advantage of being representative of the whole stomach surface and constitutes a non-aggressive test for the detection of H. pylori. This test, which has been called MIN 14C UBT, is a modification of the conventional 14C UBT in which low volumes of a solution of 14C-urea together with 99mTc-sulfur colloid are administered. The 99mTc-sulfur colloid is not absorbed in the gastrointestinal tract and has the great advantage of allowing the "visualization" of the transit of the 14C-urea within the gastrointestinal tract. This modification allows the simultaneous determination of the production of the 14CO2 and the place where this process occurs. The results show that there is a good correlation between the images obtained and the breath samples collected. We found that this test has a sensitivity of 98% and a specificity of 96% for H. pylori detection.

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 125I-L-3 Iodo-a-Methyl Tyrosine (125I-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 125I-IMT in order to be used in a Nuclear Medicine Service. The L-alpha-Methyl Tyrosine was labeled with 125I using I-/I03 and afterwards purified by an anionic exchange resin. The labeling yield obtained was (96.0 +/- 0.5)% 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)% 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 125I-IMT can be used as a diagnostic agent for pancreatic diseases. Since 123I was not available at the moment, this new methodology was developed with 125I.

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.

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. (AU)

Marcación, control y estudios de estabilidad y distribución biológica del Acido Condroitin Sulfato.Tc-99m / Labelling, control, stability and biological distribution of condroitin

Se ajustó a la técnica de preparación del ACS.Tc-99m descrita por Dupuy y col., encontrándose el pH óptimo para su estabilidad. Se estudió la distribución biológica en ratones, determinando el porcentaje de dosis inyectada en distintos órganos, a diferentes tiempos

Marcación, control y estudios de estabilidad y distribución biológica del Acido Condroitin Sulfato.Tc-99m / Labelling, control, stability and biological distribution of condroitin

Se ajustó a la técnica de preparación del ACS.Tc-99m descrita por Dupuy y col., encontrándose el pH óptimo para su estabilidad. Se estudió la distribución biológica en ratones, determinando el porcentaje de dosis inyectada en distintos órganos, a diferentes tiempos

Síntesis y control del MAG3 99mTc. Estudios comparativos con el hipurán 131I en seres humanos / Syntesis and control of Tc99m MAG3: comparative study with 131I hippuran in humans

La benzoilmercaptoacetiltriglicina (MAG,) se sintetizó de acuerdo con el método de A.R.Fritzberg y colaboradores. Se comprobó su pureza por punto de fusión, composición centesimal, cromatografía líquida de alta presión y resonancia magnética nuclear. Se realizaron estudios farmacológicos, esterilidad, apirogenicidad, toxicidad aguda y distribución biológica en animales. El producto (MAG,) marcado con tecnecio 99m, según la técnica de J.R.Coveney y M.S.Roblins, se controló por cromatografía en papel. Posteriormente, se inyectó en seres humanos (2,5-3 ,Ci) en normales y con patología renal (39 casos totales) realizándose el estudio comparativo con hipurán

Síntesis y control del MAG3 99mTc. Estudios comparativos con el hipurán 131I en seres humanos / Syntesis and control of Tc99m MAG3: comparative study with 131I hippuran in humans

La benzoilmercaptoacetiltriglicina (MAG,) se sintetizó de acuerdo con el método de A.R.Fritzberg y colaboradores. Se comprobó su pureza por punto de fusión, composición centesimal, cromatografía líquida de alta presión y resonancia magnética nuclear. Se realizaron estudios farmacológicos, esterilidad, apirogenicidad, toxicidad aguda y distribución biológica en animales. El producto (MAG,) marcado con tecnecio 99m, según la técnica de J.R.Coveney y M.S.Roblins, se controló por cromatografía en papel. Posteriormente, se inyectó en seres humanos (2,5-3 ,Ci) en normales y con patología renal (39 casos totales) realizándose el estudio comparativo con hipurán

Simultaneous measurement of ventricular function and myocardial perfusion using the technetium-99m isonitriles.

To assess both ventricular function and myocardial perfusion, five normal volunteers, 19 patients with coronary artery disease, and two patients with cardiomyopathy and normal coronary arteries were injected with 20 mCi of Tc-99m isonitrile (either methoxyisobutyl isonitrile or carbomethoxyisopropyl isonitrile) at peak bicycle exercise and again at rest. A standard Tl-201 stress test was performed in all patients at the same level of exercise within one month of the isonitrile study. In all normal subjects, myocardial perfusion was normal at stress levels and the left ventricular ejection fraction increased 5% or more with exercise. In the 19 patients with coronary artery disease, the ejection fraction response to exercise was abnormal in 14 patients. Perfusion images with the Tc-99m isonitriles correlated well with Tl-201 images during exercise and at rest, with 89% concordance in areas of ischemia or infarction and 93% in normal segments. A simultaneous study of myocardial perfusion and ventricular function can be performed using a single Tc-99m labeled myocardial agent. Tc-99m isonitriles, particularly Tc-99m MIBI, result in sufficiently high photon flux that ventricular performance can be studied at peak exercise and again during rest using the first pass method.

[Simultaneous test of ventricular function and myocardial perfusion, during exercise, using a new agent labeled with Tc99m]. / Test simultáneo de función ventricular y perfusión miocárdica, durante el ejercicio, mediante un nuevo agente marcado con Tc99m.

One a tribute of a Tc 99m labeled myocardial agent is the possibility to measure both ventricular function and myocardial perfusion with a single injection. To assess this, normal volunteers, 14 patients with coronary artery disease (CAD) and two suffering from cardiomyopathy with normal coronaries, were injected with 8-10 mci carbomethoxy-isopropyl-isonitrile or 20 mci Rp-30 Tc 99m at peak semi-recumbent bicycle exercise and again at rest. Thirty msec per frame first pass data, and 5 min static anterior, 40(0-) and 70(0-) left anterior oblique images were obtained. Standard Thallium 201 stress test were also done, within one month, and were at the same level of exercise. The left ventricular ejection fraction (EF) increased with exercise (69%-76%) in normal patients. All studies showed normal myocardial perfusion on exercise. In CAD patients the EF increased in some patients who had ischemia. Perfusion images with Tc 99m during exercise and at rest had an identical correlation with Thallium 201. The results support the concept of dual ventricular function and perfusion studies using a single Tc 99m labelled myocardial agent, and suggest that this could become the standard radionuclide stress tests in the future.

Myocardial imaging with technetium-99m CPI: initial experience in the human.

The hexakis(isonitrile)technetium(I) analog [99mTc]carbomethoxyisopropyl isonitrile (CPI) has high myocardial uptake and rapid lung and liver clearance in most animal species. To evaluate [99mTc]CPI as a myocardial imaging agent in the human, we evaluated this tracer in three normals and in six patients with coronary artery disease (CAD). In normals, [99mTc]CPI cleared quickly from the lungs and accumulated in the liver and heart. The liver activity peaked at 10-15 min and cleared through the hepatobiliary system. Planar images were of excellent technical quality with high myocardial to background ratios as early as 10 min after injection. Myocardial activity fell gradually to 76.1 +/- 2.9 (s.d.)% of initial activity by 60 min after injection. In six patients with CAD, myocardial defects were present on planar images up to 2 hr after exercise and injection. In one out of six patients, the defect was not seen 3 hr after injection. In five of the six patients, normal perfusion patterns were observed 1 hr after reinjection of CPI at rest (4 hr after the initial injection). In one patient who developed spontaneous angina prior to reinjection, the perfusion defects persisted. The repeat study 3 days later with injection of [99mTc]CPI at rest was normal. Technetium-99m CPI appears to have excellent physical and biologic properties for use in association with myocardial imaging with exercise.

The utilization of Tc-99m-TBI as a myocardial perfusion agent in exercise studies: comparison with Tl-201 thallous chloride and examination of its biodistribution in humans.

Twenty-four patients were studied with both 201Tl-thallous chloride and 99mTc-TBI scintigraphy following exercise. Comparison of the two agents in detecting segmental myocardial ischemia and scar was made in 18 patients with evidence of coronary artery disease on 201Tl-thallous chloride scintigraphy. Agreement between the two studies was observed in 77% (125 of 162) of left ventricular segments, suggesting that 99mTc-TBI can be used as a myocardial perfusion agent. Limitations were related to early high background activity from lungs and liver. The high lung activity and early myocardial redistribution within the 1st hour contributed to the failure of 99mTc-TBI to detect 16 segmental defects seen in the immediate post-exercise thallous chloride scan. Persistently high liver activity additionally affected accurate interpretation in the left ventricular segments close to the diaphragm. Improvement in the accuracy of 99mTc-TBI stress studies might be achieved with tomographic imaging to reduce the problem of background activity or by the development of 99mTc-labeled isonitrile analogues with rapid lung and liver clearance.

Pharmacokinetic study of 2-(2'-methyl-3'-chloro-anilino)-lysine nicotinate (L-104).

The pharmacokinetic study of a new analgesic-antiinflammatory agent, 2-(2'-methyl-3'-chloro-anilino)lysine nicotinate (L-104), was preformed in the rat and the dog. When administered p.o. in rats at a dose of 40 mg/kg, the serum peak was 131.3 microgram/ml +/- 10.3 at 15 min post application, and the elimination t 1/2 was 1.20 h. For the same dose, given i.v., the biological t 1/2 was 1.38 h, the AUC 337.18 microgram/ml/h and the Vdss 0.232 l/kg. When administered i.v. in dogs of 10 mg/kg, the biological t 1/2 was 0.96 h +/- 0.14, the AUC 73,066 microgram/ml/h and the Vdss 0.178 l/kg. In the rat, for a dose of 40 mg/kg given p.o., 79.1% of tritium-labelled L-104 were excreted within 72 h, 56.0% of them through the kidneys. In the dog, at an i.v. dose of 10 mg/kg, the whole of the drug was excreted at the end of 72 h, corresponding 52.6% urinary excretion. The main metabolite in the rat was 2-(2'-methyl-3'-chloro-4'-hydroxy-anilino)-nicotinic acid (72.2%), whereas in the dog it was 2-(2'-methyl-3'-chloro-anilino)-5-hydroxy-nicotinic acid (35.2%).