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1.
Radiologia (Engl Ed) ; 65(1): 12-21, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36842781

RESUMO

OBJECTIVE: To contribute our results to increase the scientific evidence about the use of radioembolization in the management of patients with hepatocellular carcinoma. MATERIAL AND METHODS: This retrospective review included 53 patients with hepatocellular carcinoma treated with radioembolization at our center. Patients were classified according to the BCLC algorithm in detail according to their Child-Pugh functional status. We analyzed survival using the Kaplan-Meier method. We used Cox regression analysis to determine clinically significant parameters, including the doses administered in the parameters studied. RESULTS: Patients ranged in age from 28 to 86 years (mean, 60 years). A total of 61 procedures were done. The mean activity administered was 2.8GBq (0.7-6.4GBq), with a mean dose of 229.9Gy (74-425.9Gy) administered in the tumor. Progression-free survival was 6.7 months and overall survival was 12.8 months. Differences in disease-free survival according to BCLC and Child-Pugh classification were not significant (p=0.848 and p=0.252, respectively). The clinical parameters that were significantly different with respect to overall survival were bilirubin levels (p<0.001), pretreatment transaminase levels (AST) (p=0.022), Child-Pugh subclassification (p=0.003), and dose administered in the tumor (p=0.001). Only one patient had a severe adverse reaction, developing posttreatment liver failure resulting in death. CONCLUSIONS: Radioembolization is safe and efficacious in the treatment of patients with hepatocellular carcinoma. Liver function and the doses received by the tumor are key parameters for the efficacy of treatment. The increase in the scientific evidence supports the inclusion of this technique in treatment guidelines.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Intervalo Livre de Doença , Estudos Retrospectivos , Embolização Terapêutica/métodos
2.
Radiología (Madr., Ed. impr.) ; 65(1): 12-21, ene.-feb. 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-215019

RESUMO

Objetivo Contribuir con la presentación de los resultados de nuestro estudio a ampliar la evidencia científica sobre el empleo de la radioembolización en el manejo de pacientes con hepatocarcinoma. Material y método Se trata de una revisión retrospectiva realizada en nuestro centro que incluye a 53 pacientes con hepatocarcinoma tratados con radioembolización. Los pacientes fueron clasificados según el algoritmo del BCLC (Barcelona Clinic Liver Cancer) y de forma pormenorizada por su estado funcional siguiendo la clasificación de Child-Pugh. Se realizó un estudio de supervivencia siguiendo la metodología de Kaplan-Meier. Se empleó el método de regresión de Cox para la determinación de parámetros clínicos significativos, incluyendo dosis administradas en los parámetros estudiados. Resultados La serie evaluada comprende a pacientes con una media de edad de 60 años (rango 28-86). Se llevaron a cabo un total de 61 procedimientos. La actividad media administrada fue de 2,8 GBq (0,7-6,4 GBq), administrando una dosis media en tumor de 229,9 Gy (74-425,9 Gy). El tiempo libre de progresión fue de 6,7 meses desde el momento del tratamiento y la supervivencia global fue de 12,8 meses. La clasificación de los pacientes según BCLC (p=0,848) y Child-Pugh (p=0,252) no resultó significativa respecto al tiempo libre de enfermedad. Los parámetros clínicos que resultaron con diferencias significativas en cuanto a supervivencia global fueron los niveles de bilirrubina (p<0.001) y las cifras de transaminasas (GOT) pretratamiento (p=0.022), la subclasificación Child-Pugh (p=0.003) y la dosis recibida por el tumor (p=0,001). Tan solo uno de los pacientes tratados presentó un efecto adverso grave, con fallo hepático posterapia y resultado de muerte... (AU)


Objective To contribute our results to increase the scientific evidence about the use of radioembolization in the management of patients with hepatocellular carcinoma. Material and methods This retrospective review included 53 patients with hepatocellular carcinoma treated with radioembolization at our center. Patients were classified according to the BCLC algorithm in detail according to their Child-Pugh functional status. We analyzed survival using the Kaplan-Meier method. We used Cox regression analysis to determine clinically significant parameters, including the doses administered in the parameters studied. Results Patients ranged in age from 28 to 86 years (mean, 60 years). A total of 61 procedures were done. The mean activity administered was 2.8 GBq (0.7-6.4 GBq), with a mean dose of 229.9Gy (74-425.9Gy) administered in the tumor. Progression-free survival was 6.7 months and overall survival was 12.8 months. Differences in disease-free survival according to BCLC and Child-Pugh classification were not significant (p=0.848 and p=0.252, respectively). The clinical parameters that were significantly different with respect to overall survival were bilirubin levels (p<0.001), pretreatment transaminase levels (AST) (p=0.022), Child-Pugh subclassification (p=0.003), and dose administered in the tumor (p=0.001). Only one patient had a severe adverse reaction, developing posttreatment liver failure resulting in death. Conclusions Radioembolization is safe and efficacious in the treatment of patients with hepatocellular carcinoma. Liver function and the doses received by the tumor are key parameters for the efficacy of treatment. The increase in the scientific evidence supports the inclusion of this technique in treatment guidelines. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Braquiterapia/métodos , Radioisótopos de Ítrio/uso terapêutico , Estimativa de Kaplan-Meier , Resultado do Tratamento , Estudos Retrospectivos
3.
Radiologia (Engl Ed) ; 2020 Nov 27.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33257052

RESUMO

OBJECTIVE: To contribute our results to increase the scientific evidence about the use of radioembolization in the management of patients with hepatocellular carcinoma. MATERIAL AND METHODS: This retrospective review included 53 patients with hepatocellular carcinoma treated with radioembolization at our center. Patients were classified according to the BCLC algorithm in detail according to their Child-Pugh functional status. We analyzed survival using the Kaplan-Meier method. We used Cox regression analysis to determine clinically significant parameters, including the doses administered in the parameters studied. RESULTS: Patients ranged in age from 28 to 86 years (mean, 60 years). A total of 61 procedures were done. The mean activity administered was 2.8 GBq (0.7-6.4 GBq), with a mean dose of 229.9Gy (74-425.9Gy) administered in the tumor. Progression-free survival was 6.7 months and overall survival was 12.8 months. Differences in disease-free survival according to BCLC and Child-Pugh classification were not significant (p=0.848 and p=0.252, respectively). The clinical parameters that were significantly different with respect to overall survival were bilirubin levels (p<0.001), pretreatment transaminase levels (AST) (p=0.022), Child-Pugh subclassification (p=0.003), and dose administered in the tumor (p=0.001). Only one patient had a severe adverse reaction, developing posttreatment liver failure resulting in death. CONCLUSIONS: Radioembolization is safe and efficacious in the treatment of patients with hepatocellular carcinoma. Liver function and the doses received by the tumor are key parameters for the efficacy of treatment. The increase in the scientific evidence supports the inclusion of this technique in treatment guidelines.

4.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 36(2): 116-119, mar.-abr. 2017. ilus
Artigo em Inglês | IBECS | ID: ibc-160785

RESUMO

Ante un paciente con cáncer diferenciado de tiroides, el protocolo de tratamiento estándar a seguir es cirugía, ablación con 131Iodo (131I) de restos tiroideos y supresión de TSH. Pero en algunos casos, el tratamiento con 131I no es efectivo y deja de ser una opción terapéutica debido a la desdiferenciación celular con pérdida de la captación de 131I. Como otras opciones, se puede recurrir a tratamiento sistémico, si bien los pacientes no siempre son respondedores, pudiendo progresar la enfermedad y quedando sin opciones terapéuticas. Los tumores endocrinos pueden expresar receptores de la somatostatina, lo que se ha utilizado tanto para el diagnóstico como para su tratamiento mediante el marcaje de los análogos de la somatostatina con isótopos radiactivos. Presentamos el caso de una paciente con carcinoma folicular de tiroides yodorrefractario, con expresión de receptores de la somatostatina, tratada con 177Lu-DOTATATE, con excelente respuesta clínica y analítica (AU)


In a patient with a differentiated thyroid cancer the standard treatment protocol to be followed is surgery, ablation of thyroid remnants with 131Iodine (131I), and TSH suppression. However, the treatment with 131I is not effective in some cases, and it no longer becomes a therapeutic option due to cell de-differentiation with loss of 131I uptake. Systemic treatment can be used as other options, although patients are not always responsive; thus, the disease may progress and therapeutic options may run out. Endocrine tumours may express somatostatin receptors,and this characteristic has been used, not only for diagnosis, but also for their treatment through somatostatin analogue labelling with radioactive isotopes. This was the case of a patient suffering from iodine-refractory follicular thyroid carcinoma, with somatostatin receptors expression, treated with 177Lu-DOTATATE, showing an excellent clinical and analytical response (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma/diagnóstico , Carcinoma , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide , Compostos Radiofarmacêuticos/uso terapêutico , Oligoelementos/uso terapêutico , Somatostatina/análogos & derivados , Iodo/uso terapêutico , Compostos Radiofarmacêuticos/análise , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos , Qualidade de Vida , Medicina Nuclear/métodos
5.
Rev Esp Med Nucl Imagen Mol ; 36(2): 116-119, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27793633

RESUMO

In a patient with a differentiated thyroid cancer the standard treatment protocol to be followed is surgery, ablation of thyroid remnants with 131Iodine (131I), and TSH suppression. However, the treatment with 131I is not effective in some cases, and it no longer becomes a therapeutic option due to cell de-differentiation with loss of 131I uptake. Systemic treatment can be used as other options, although patients are not always responsive; thus, the disease may progress and therapeutic options may run out. Endocrine tumours may express somatostatin receptors,and this characteristic has been used, not only for diagnosis, but also for their treatment through somatostatin analogue labelling with radioactive isotopes. This was the case of a patient suffering from iodine-refractory follicular thyroid carcinoma, with somatostatin receptors expression, treated with 177Lu-DOTATATE, showing an excellent clinical and analytical response.


Assuntos
Adenocarcinoma Folicular/radioterapia , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Lutécio/uso terapêutico , Octreotida/análogos & derivados , Compostos Organometálicos/uso terapêutico , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Adenocarcinoma Folicular/sangue , Adenocarcinoma Folicular/tratamento farmacológico , Adenocarcinoma Folicular/cirurgia , Idoso , Antibióticos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Terapia Combinada , Doxorrubicina/uso terapêutico , Everolimo/uso terapêutico , Feminino , Bócio Nodular/complicações , Bócio Nodular/cirurgia , Humanos , Indazóis , Radioisótopos do Iodo/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Octreotida/uso terapêutico , Cuidados Paliativos , Compostos de Fenilureia/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Pirimidinas/uso terapêutico , Sorafenibe , Sulfonamidas/uso terapêutico , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
6.
Radiología (Madr., Ed. impr.) ; 58(6): 468-480, nov.-dic. 2016. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-158680

RESUMO

La tomografía por emisión de positrones (PET) es una técnica de imagen que en los últimos años ha experimentado un gran crecimiento y se considera una herramienta básica de gran utilidad en el campo de la oncología, sin olvidar sus indicaciones en otras áreas como la neurología y la cardiología. Aunque la 18F-fluorodeoxyglucose (18F-FDG) es el radiofármaco más ampliamente utilizado en PET, disponer de nuevos radiotrazadores ha sido un elemento clave en la expansión de esta técnica porque han permitido estudiar diferentes dianas biológicas esenciales para un mayor conocimiento y una mejor caracterización de diferentes patologías, contribuyendo de esta forma a la investigación y el desarrollo de nuevos agentes terapéuticos. En este trabajo se hace una descripción de varios radiofármacos para PET, estructurada según su área de aplicación. Algunos de ellos ya están disponibles comercialmente, mientras que otros todavía están en fase de investigación o pendientes de autorización (AU)


Positron emission tomography (PET) is an imaging technique that has grown greatly in recent years. PET is considered a fundamental tool in oncology, and it also has indications in other fields such as neurology and cardiology. Although 18F-fluorodeoxyglucose (18F-FDG) is the radiopharmaceutical most widely used in PET, the availability of new radiotracers has been a key element in the expansion of the use of PET. These new radiopharmaceuticals have made it possible to study different biological targets that are essential for obtaining greater knowledge and better characterization of different diseases and have thus contributed to the research and development of different therapeutic agents. This article provides a description of different PET radiopharmaceutical, structured according to their areas of application. Some of these radiotracers are already commercially available, whereas others are still under research or pending approval by regulatory bodies (AU)


Assuntos
Humanos , Masculino , Feminino , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/efeitos da radiação , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão/métodos , 34944 , Neoplasias , Compostos Radiofarmacêuticos/química , Imageamento por Ressonância Magnética/métodos
7.
Radiologia ; 58(6): 468-480, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27592111

RESUMO

Positron emission tomography (PET) is an imaging technique that has grown greatly in recent years. PET is considered a fundamental tool in oncology, and it also has indications in other fields such as neurology and cardiology. Although 18F-fluorodeoxyglucose (18F-FDG) is the radiopharmaceutical most widely used in PET, the availability of new radiotracers has been a key element in the expansion of the use of PET. These new radiopharmaceuticals have made it possible to study different biological targets that are essential for obtaining greater knowledge and better characterization of different diseases and have thus contributed to the research and development of different therapeutic agents. This article provides a description of different PET radiopharmaceutical, structured according to their areas of application. Some of these radiotracers are already commercially available, whereas others are still under research or pending approval by regulatory bodies.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Previsões , Cardiopatias/diagnóstico por imagem , Humanos , Neoplasias/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/tendências
8.
Rev. esp. med. nucl. (Ed. impr.) ; 29(3): 114-121, mayo-jun. 2010. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-79410

RESUMO

ObjetivoRevaluar la dosis efectiva (E) de las exploraciones típicas en Medicina Nuclear teniendo en cuenta los nuevos factores de ponderación de la Comisión Internacional de Protección Radiológica (ICRP) 103 y los datos más actualizados en cuanto a la dosimetría, y relacionar la E con el tiempo equivalente de radiación natural (TERN).Material y métodosSe ha calculado la E asociada a los radiofármacos y a las exploraciones habituales en Medicina Nuclear para las edades: adulto, 15, 10, 5 y 1 año. Se han empleado los datos dosimétricos de ICRP-106, ICRP-80, ICRP-53 y/o prospecto del fabricante.ResultadosSe muestra una relación de datos de E asociada a radiofármacos y exploraciones. Los nuevos factores de ponderación de tejidos dan como resultado un valor disminuido de la E, excepto en aquellos casos que afectan especialmente a la mama, para los que aumenta. La E asociada a las exploraciones de Medicina Nuclear está en el rango de 0,1–60mSv. El TERN va desde unos pocos días a una veintena de años. La E asociada a exploraciones que se realizan en niños es, en general, superior a la E correspondiente en adulto.ConclusionesLos resultados mostrados en este trabajo constituyen una colección actualizada de valores de E para los radiofármacos de uso habitual en Medicina Nuclear. Expresar la E en unidades de TERN ayuda a explicar a los pacientes y al personal sanitario cuestiones relacionadas con la exposición a la radiación asociada a una exploración(AU)


ObjectiveRe-evaluate the effective dose (E) of typical nuclear medicine procedures using the new ICRP-103 weighting factors and the latest dosimetry data and relate E with Background Equivalent Radiation Time (BERT).Material and MethodsEffective dose associated with radiopharmaceuticals and nuclear medicine procedures has been calculated for the following ages: adult, 15, 10, 5 and 1 year. Dosimetry data have been extracted from ICRP-106, ICRP-80, ICRP-53 and/or manufacturer's brochure.ResultsThe relationship of the data of effective dose associated with radiopharmaceuticals and explorations is shown. The new tissue weighting factors result in a decreased value of the effective dose, except in cases that particularly affect the breast, in which it increases. The effective dose associated with nuclear medicine procedures is in the range 0.1–60mSv. BERT ranges from a few days to 20 years. The effective dose associated to tests in children is generally higher than the effective dose for an adult.ConclusionsThe results shown in this paper are an updated collection of effective dose values for commonly used radiopharmaceuticals in nuclear medicine. Expressing the effective dose equivalent time in units of natural radiation helps to explain issues associated with radiation exposure to patients and healthcare personnel(AU)


Assuntos
Humanos , Doses de Radiação , Medicina Nuclear/normas , Radioisótopos/administração & dosagem , Radiometria , Relação Dose-Resposta à Radiação
9.
Rev Esp Med Nucl ; 29(3): 114-21, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20399539

RESUMO

OBJECTIVE: Re-evaluate the effective dose (E) of typical nuclear medicine procedures using the new ICRP-103 weighting factors and the latest dosimetry data and relate E with Background Equivalent Radiation Time (BERT). MATERIAL AND METHODS: Effective dose associated with radiopharmaceuticals and nuclear medicine procedures has been calculated for the following ages: adult, 15, 10, 5 and 1 year. Dosimetry data have been extracted from ICRP-106, ICRP-80, ICRP-53 and/or manufacturer's brochure. RESULTS: The relationship of the data of effective dose associated with radiopharmaceuticals and explorations is shown. The new tissue weighting factors result in a decreased value of the effective dose, except in cases that particularly affect the breast, in which it increases. The effective dose associated with nuclear medicine procedures is in the range 0.1-60 mSv. BERT ranges from a few days to 20 years. The effective dose associated to tests in children is generally higher than the effective dose for an adult. CONCLUSIONS: The results shown in this paper are an updated collection of effective dose values for commonly used radiopharmaceuticals in nuclear medicine. Expressing the effective dose equivalent time in units of natural radiation helps to explain issues associated with radiation exposure to patients and healthcare personnel.


Assuntos
Algoritmos , Relação Dose-Resposta à Radiação , Medicina Nuclear/estatística & dados numéricos , Radiometria/estatística & dados numéricos , Adulto , Fatores Etários , Criança , Humanos , Especificidade de Órgãos , Doses de Radiação , Radioisótopos/administração & dosagem , Padrões de Referência
10.
Ars pharm ; 50(4): 224-234, oct.-dic. 2009. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-81364

RESUMO

Se ha elaborado un modelo para el estudio de la cinética y equilibrio de las reacciones antígeno-anticuerpo implicadas en el radioinmunoanálisis (RIA) de doble anticuerpo correspondiente al Péptido C. Se pretende caracterizar la influencia de las concentraciones iniciales de antígeno marcado (M) y no marcado (Q) sobre la formación del inmunocomplejo (PM) al segundo anticuerpo (J) inmovilizado sobre una bola. Se realizan 30 experiencias para el estudio del efecto de las variables antes mencionadas. Los resultados obtenidos son concordantes con el modelo propuesto(AU)


A model has been produced for the kinetic and equilibrium study of antigen-antibody reactions in the radioimmunoassay (RIA) of C-Peptide double antibody. The aim is (1) to characterise the influence of initial concentrations of labelled (M) and unlabelled (Q) antigen and that of the initial concentration of the antibody in solution (P), and (2) to study the binding of the immunocomplex (PM) to the second antibody (J) immobilised on a bead, and the replacement of M by Q in the PMJ immunocomplex. In order to study the effect of such variables, 44 experiments were conducted. The results are in line with the model proposed(AU)


Assuntos
Complexo Antígeno-Anticorpo , Radioimunoensaio , Peptídeo C , Análise por Ativação , Farmacocinética
11.
Ars pharm ; 50(4): 235-247, oct.-dic. 2009. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-81365

RESUMO

Se ha elaborado un modelo para el estudio de la cinética y equilibrio de las reacciones antígeno-anticuerpo implicadas en el radioinmunoanálisis (RIA) de doble anticuerpo correspondiente al Péptido C. Se pretende caracterizar la influencia de las concentraciones iniciales de antígeno marcado (M) y no marcado (Q) sobre la formación del inmunocomplejo (PM) al segundo anticuerpo (J) inmovilizado sobre una bola. Se realizan 30 experiencias para el estudio del efecto de las variables antes mencionadas. Los resultados obtenidos son concordantes con el modelo propuesto(AU)


A model has been produced for the kinetic and equilibrium study of antigen-antibody reactions in the radioimmunoassay (RIA) of C-Peptide double antibody. The aim is (1) to characterise the influence of initial concentrations of labelled (M) and unlabelled (Q) antigen and that of the initial concentration of the antibody in solution (P), and (2) to study the binding of the immunocomplex (PM) to the second antibody (J) immobilised on a bead, and the replacement of M by Q in the PMJ immunocomplex. In order to study the effect of such variables, 44 experiments were conducted. The results are in line with the model proposed(AU)


Assuntos
Complexo Antígeno-Anticorpo , Radioimunoensaio , Peptídeo C , Análise por Ativação , Farmacocinética
12.
Transplant Proc ; 40(9): 3020-2, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010178

RESUMO

BACKGROUND: The incidence and prevalence of heart failure (HF) are constantly increasing. Heart failure depends on pump failure, inflammatory tracers, and the neurohormonal system. At advanced stages, the only treatment is heart transplantation (HT). We studied myocardial innervation in patients before HT. MATERIALS AND METHODS: The study included 15 patients (11 men and 4 women; age range, 18-69 years) with a diagnosis of New York Heart Association class III-IV or IV HF. Planar thoracic images were obtained, at 15 minutes and 4 hours after injection of 10 mCi of iodine 123-metaiodobenzylguanidine ((123)I-MIBG). Adrenal activity was measured quantitatively using a heart-to-mediastinum count ratio and a myocardial washout rate. Pathologic results were considered if heart-to-mediastinum count ratio was less than 1.8 and washout rate was more than 35%. RESULTS: The qualitative analysis revealed decreased (123)I-MIBG myocardial uptake in all patients. Using the quantitative scale, patients were classified into four groups, as follows: group 1, physiologic innervation, no patients; group 2, mild myocardial adrenergic involvement, one patient (6.7%); group 3, moderate myocardial adrenergic involvement, five patients (33.3%); and group 4, severe myocardial adrenergic involvement, 9 patients (60%). The washout rate was pathologic in 11 of the 15 patients (73.3%). CONCLUSIONS: Scintigraphy using (123)I-MIBG is a useful method to evaluate prognosis in patients with advanced HF and can be used to assess transplantation priorities. It will be necessary to study a larger number of patients to confirm these findings.


Assuntos
3-Iodobenzilguanidina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/cirurgia , Transplante de Coração/métodos , Coração/inervação , 3-Iodobenzilguanidina/farmacocinética , Adolescente , Adulto , Idoso , Transporte Biológico , Criança , Feminino , Coração/efeitos dos fármacos , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Pré-Medicação/métodos , Prognóstico , Tomografia Computadorizada de Emissão , Adulto Jovem
13.
J Immunoassay Immunochem ; 23(4): 407-28, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12458725

RESUMO

The kinetics of insulin reaction has been studied with its specific antibody immobilized on the inner wall of the reaction tube; the radioimmunoanalytical determination of such a substance is based on the reaction. Independent variables were labelled and unlabelled insulin concentrations, temperature, viscosity, and the medium's ionic strength. Biexponential kinetics was found to be dependent on the concentrations fitted to the models discussed in the paper. The effect of temperature shows activation parameters similar to the viscous flow energy of water, which suggests that the reaction is diffusion-controlled. The results of the viscosity analysis points at the clearly negative influence of viscosity upon the direct reaction rate. Ionic strength has a noticeable, though not relevant, effect which seems to indicate that the variation resulting from the glycerol addition is not due to the influence of the dielectric constant in the solutions used.


Assuntos
Insulina/química , Radioimunoensaio/métodos , Bioquímica/métodos , Humanos , Cinética , Temperatura
14.
J Pharm Biomed Anal ; 26(4): 547-62, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11516905

RESUMO

This paper analyses the influence of viscosity and ionic strength on the kinetics and equilibrium of the reactions of (125)I labelled androstendione and aldosterone with their specific antibodies used in the radioactive immunoassay determination of such hormones. Bi-exponential and irreversible kinetics is found for androstendione, and single-exponential and reversible ones for aldosterone. The results of the viscosity analysis reflect clear negative influence on direct reaction rate. Ionic strength excerpts some influence but not in a significant way, which suggests that the variation resulting from the effect of the glycerol addition is not due to the influence of the dielectric constant of the solutions used. The apparent product of the electrical charges is 0.228 for aldosterone, and 0.230 and -0.230 for androstendione. Results show diffusive control for both cases.


Assuntos
Aldosterona/química , Androstenodiona/química , Modelos Químicos , Aldosterona/imunologia , Androstenodiona/imunologia , Reações Antígeno-Anticorpo , Cinética , Concentração Osmolar , Radioimunoensaio , Viscosidade
15.
Ars pharm ; 41(2): 189-202, abr. 2000. tab
Artigo em Es | IBECS | ID: ibc-23467

RESUMO

Se ha estudiado la cinética de la reacción entre la androstendiona marcada con 125I y su anticuerpo específico utilizado en la determinación radioinmunoanalítica de dicha sustancia, encontrándose resultados ajustables a un modelo michaeliano. La presencia de androstendiona no marcada afecta a la reacción de un modo competitivo. Se encuentran cinéticas biexponenciales que sugieren reacciones con epítopos distintos. La influencia de la temperatura indica un control por difusión. Los resultados de equilibrio se ajustan al modelo de unión de dos ligandos sobre sitios independientes. Se desarrollan modelos teóricos compatibles con los resultados experimentales (AU)


Assuntos
Humanos , Androstenodiona/farmacocinética , Radioimunodetecção/métodos , Modelos Teóricos , Traçadores Radioativos , Reações Antígeno-Anticorpo/imunologia
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