RESUMO
Potassium-40 constitutes the main natural source of potassium present in the body, which influences the effective dose received by people. With the aim of assessing the contribution of this component to the doses received by the Cuban population, a study intended to assess the doses was developed. For this purpose, a representative sample of the Cuban population was selected according to age and sex. The measurements were made using the whole-body counter (WBC) of the Center for Radiation Protection and Hygiene (CPHR). For dose estimations, a uniform distribution of potassium for the whole body was assumed. The methodology used was the one recommended by the ICRP. The values of annual effective dose range between 93 and 209 microSv for females and between 123 and 212 microSv for males. The annual average effective dose for members of the public was estimated as 150 +/- 40 microSv, taking into account the experimental data and the specific features of the Cuban population. With the dose values obtained, it was possible to model dose estimates by means of a neural network, which was trained with the results obtained and using as starting data the sex, age, height and corporal weight of people studied. The modelobtained allows consideration of the anatomical features of each person in the estimation of doses.
Assuntos
Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Modelos Biológicos , Redes Neurais de Computação , Radioisótopos de Potássio/análise , Radioisótopos de Potássio/farmacocinética , Medição de Risco/métodos , Contagem Corporal Total/métodos , Adolescente , Adulto , Distribuição por Idade , Idoso , Algoritmos , Carga Corporal (Radioterapia) , Criança , Pré-Escolar , Simulação por Computador , Cuba/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Doses de Radiação , Eficiência Biológica Relativa , Tamanho da Amostra , Distribuição por SexoRESUMO
Osteosarcoma is a rare cancer, which metastasizes to the lung in up to 80% of cases. Thrombin is involved in metastasis and is present in the lungs of patients with pulmonary metastases (PM). To identify its role in PM and osteosarcoma, we measured thrombin levels in the bronchoalveolar lavage fluid (BALF) of 15 patients. BALF was collected at different stages of the disease and correlated with the diagnosis of PM. We also assessed fibrinogen overexpression in the tumors. We found that 11/15 (73%) patients with high thrombin levels in the lungs developed PM within the first 12 months from primary surgery. The median thrombin concentration in the BALF of these patients increased up to 8x10(-9) M (range, 3x10(-9)M-15x10(-9)M), which represents a more than 100-fold increase compared to patients without PM (p<0.0001). Eight of 15 (53%) primary and 11/15 (73%) metastatic samples showed fibrinogen overexpression. A significant difference between high thrombin levels, fibrinogen overexpression and PM was found compared to patients without PM (p=0.00073 and p=0.025). These results show that thrombin levels are increased in the lungs of patients with primary osteosarcoma and a high risk of developing PM. They suggest that thrombin may be involved in the development of PM.
Assuntos
Neoplasias Ósseas/patologia , Neoplasias Pulmonares/secundário , Pulmão/química , Osteossarcoma/secundário , Trombina/análise , Líquido da Lavagem Broncoalveolar/química , Extremidades , Fibrinogênio/biossíntese , Humanos , Neoplasias Pulmonares/química , Osteossarcoma/patologiaRESUMO
Alterations in Ki-67 activity have been associated with tumor progression and poor outcome in cancer patients. This study was undertaken to identify the potential of this proliferative marker as a predictor of pulmonary metastases (PM) and mortality in osteosarcoma patients. In 38 patients with tissue available for immunohistochemical analysis, overexpression of Ki-67 was assessed. Chi-square and log rank tests were used to determine differences between proportions of the marker with PM and mortality and survival distributions respectively. P values equal or less than .05 were considered statistically significant. The median follow up of this case series was 28 months. Eighteen (47.4%) of 38 patients developed PM, and 17 (44%) overexpressed Ki-67. We found a high frequency of PM (15 of 17) among those cases that overexpressed Ki-67. This relationship was significant (P = .000006) when compared to the rest of the group. We also found a statistically significant correlation between patients with positive and negative Ki-67 scores and higher and lower mortality (P = .000962). These findings suggest that Ki-67 overexpression could be used as a prognostic molecular marker for the development of PM in osteosarcoma patients.
Assuntos
Neoplasias Ósseas/patologia , Antígeno Ki-67/metabolismo , Neoplasias Pulmonares/secundário , Osteossarcoma/secundário , Adulto , Anticorpos Monoclonais/imunologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/mortalidade , Feminino , Seguimentos , Humanos , Imunofenotipagem , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Osteossarcoma/metabolismo , Osteossarcoma/mortalidade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Early cellular events in the lung which may lead to the development of pulmonary metastases (PM) are still poorly understood. Thrombin, a key component of the coagulation cascade, may be involved in the development of PM as it has been shown to be an enhancer of platelet-tumor interaction in vitro and metastasis in vivo, and because it has been found in high levels in lungs from patients with PM. In this study, we assessed the potential role of thrombin in promoting PM by inducing an enhancement of tumor cell adhesion to platelets and tumor cell chemoinvasion and proliferation. We used bronchoalveolar lavage fluid (BALF) from 20 patients with PM. Results were compared with those from healthy controls. We found an enhancement of adhesion of PM-BALF-treated tumor cells to untreated platelets. BALF from patients with PM significantly increased chemoinvasion and proliferation in three human tumor cell lines. These activities were attenuated significantly by a thrombin inhibitor: hirudin. These results indicate that the thrombin present in the lungs of patients with PM is, at least in part, responsible for their adhesive, invasive and mitogenic activity on three different tumor cell lines. They also suggest that thrombin may be involved in the development of PM.
Assuntos
Neoplasias Pulmonares/fisiopatologia , Metástase Neoplásica/fisiopatologia , Trombina/fisiologia , Adesividade , Antitrombinas/farmacologia , Líquido da Lavagem Broncoalveolar/química , Hirudinas/farmacologia , Humanos , Técnicas In Vitro , Pulmão/química , Neoplasias Pulmonares/secundário , Processos Neoplásicos , Trombina/análise , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
Antecedentes. Los sarcomas óseos son poco frecuentes, pero inducen hasta 80 por ciento de metástasis pulmonar. En población mexicana esta información se desconoce, por lo que describimos su frecuencia en el Instituto Nacional de Cancerología. Métodos. Se revisaron los expedientes de pacientes con sarcoma, registrados entre 1986-1996. Se recabo información demográfica, la histología del tumor y el tiempo de desarrollo de la metástasis. Resultados. Se incluyeron en el estudio 173 casos. De éstos, 74 (43 por ciento) desarrollaron metástasis pulmonar; 102 (60 por ciento) fueron hombres y 71 (40 por ciento) mujeres. Se observó una mediana de edad de 21 años. Se registraron 120 (70 por ciento) casos con diagnóstico de osteosarcoma, 54 (45 por ciento) de los cuales presentaron metástasis; 35 (20 por ciento) casos de condrosarcoma, en 10 (29 por ciento) de los cuales se confirmó metástasis a pulmón y 18 (10 por ciento) casos con sarcoma de Ewing, 10 (56 por ciento) de éstos con metástasis. Considerando la fecha de ingreso, se observaron medianas de tiempo de desarrollo de metástasis pulmonar de hasta 15 meses. A 50 meses, en los pacientes con sarcoma de Ewing, se calculó una supervivencia del 60 por ciento, significativamente menor a la observada en los otros grupos (p=0.0368). Los pacientes con osteosarcoma y metástasis presentaron una supervivencia del 70 por ciento a 50 meses, significativamente menor a la registrada de los osteosarcomas sin metástasis (p=0.0319). Conclusiones. Se encontró una frecuencia del 43 por ciento de metástasis pulmonar. El osteosarcoma y el sarcoma de Ewing fueron los principales inductores de este tipo de metástasis y los grupos en los que se registraron los menores tiempos de supervivencia en presencia o no de metástasis, respectivamente
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Condrossarcoma/complicações , Neoplasias Pulmonares/etiologia , Invasividade Neoplásica , Metástase Neoplásica , Osteossarcoma/complicações , Osteossarcoma/epidemiologia , Sarcoma de Ewing/complicações , Prognóstico , SobreviventesRESUMO
The presence of specific IgE antibodies directed against common microorganisms was analyzed in a population of children. These antibodies included Escherichia coli, Proteus spp., Pseudomonas spp., Klebsiella spp., Streptococcus spp. and Staphylococcus spp. The determination of these antibodies was done by radioimmunoassay. Comparisons were made according to the parameters of age and total IgE levels. These antibodies were found in a high proportion of the cases. Statistical analysis demonstrated that the different specific IgE antibodies were present in all children, none showing special relevance. All of the antibodies studied were found to be present in a higher number of cases in the groups of older children, and in the group of children with increased total IgE levels, a significantly higher number of cases with antibacterial specific IgE antibodies was observed. The presence and the variety of the antibodies might be conditioned by individual as well as environmental factors. The role of antibodies is not well known. Although they are frequently found in allergic children, there have not been enough cases studied to establish their involvement in allergy. Understanding the role of antibodies might be of interest in the study of allergic processes exacerbated by bacterial infections.
Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulina E/sangue , Fatores Etários , Argentina , Criança , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
Lung disease caused by nonoccupational exposures to inorganic particles from the soil has been reported in several areas of the world. We tested the toxic potential of dust samples from a Mexican city (Mexicali) that is frequently affected by dust storms and is geographically related to the area of San Diego, CA, where constituents of the soil have been reported to be fibrogenic. We found that samples of Mexicali dust are a mixture of approximately 75% potassium aluminum silicates (illite) and approximately 20% silica. Respirable size particles were highly hemolytic and induced lactic dehydrogenase release from alveolar macrophages exposed in vitro. Animals instilled intratracheally with the dust developed a multifocal interstitial lung disease associated with deposits of the aluminum silicates, which were identified by X-ray microanalysis. Inhalation studies in rats demonstrated that the majority of particles were deposited preferentially at the first alveolar duct bifurcations. Twenty-four hours later, numerous particles had been ingested by alveolar macrophages that had migrated to those sites of deposition. It is proposed that alveolar macrophages are attracted to the deposited particles by complement fragments since Mexicali dust is capable of activating complement proteins from both serum and bronchoalveolar lavage. Activation resulted in alveolar macrophage chemotaxis. Mexicali dust induced biological activities and lung changes similar to those of asbestos and silica, suggesting that this material could be an etiologic agent of pulmonary fibrosis in exposed individuals.
Assuntos
Compostos de Alumínio , Silicatos de Alumínio/efeitos adversos , Poeira/efeitos adversos , Exposição Ambiental , Pulmão/citologia , Macrófagos Alveolares/citologia , Compostos de Potássio , Silicatos , Dióxido de Silício/efeitos adversos , Silicatos de Alumínio/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Sobrevivência Celular , Células Cultivadas , Quimiotaxia , Ativação do Complemento , Microanálise por Sonda Eletrônica , Hemólise , Macrófagos/imunologia , Macrófagos/fisiologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/fisiologia , Masculino , México , Ratos , Ratos Endogâmicos , Dióxido de Silício/imunologia , Difração de Raios XRESUMO
Se realizó un estudio de eosinófilos en secreción nasal y de eosinófilos, basófilos y mastocitos en membrana de mucosa nasal, en 57 pacientes. A todos se le diagnosticó alergia respiratoria por la historia clínica, número de eosinófilos en sangre periférica, IgE sérica total, pruebas cutáneas y eventualmente por la dieta de eliminación y provocación. Diez niños sanos sirvieron como controles. Las muestras del moco se obtuvieron por barrido del piso de la nariz y del meato inferior. El material fue extendido en porta-objetos, fijado y coloreado por el método de Hansel. Las muestras de mucosa nasal fueron obtenidas del cornete inferior por medio de una cureta plástica descatable (Rhino-probe), extendidas sobre un porta-objetos, fijados y coloreados con Wright-Giemsa. La eficiencia del diagnóstico de la citología de las secreciones nasales, fue similar al de la mucosa, excepto en pacientes menores de un año de edad. Fue mejor la correlación entre atopía y citología nasal cuando ésta fue positiva tanto en las secreciones como en la mucosa
Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Estudo Comparativo , Hipersensibilidade Respiratória/diagnóstico , Rinite Alérgica Perene/diagnóstico , Mucosa Nasal/citologia , Muco/análise , Mucosa Nasal/metabolismo , Muco/citologia , Citodiagnóstico/métodosRESUMO
Se realizó un estudio de eosinófilos en secreción nasal y de eosinófilos, basófilos y mastocitos en membrana de mucosa nasal, en 57 pacientes. A todos se le diagnosticó alergia respiratoria por la historia clínica, número de eosinófilos en sangre periférica, IgE sérica total, pruebas cutáneas y eventualmente por la dieta de eliminación y provocación. Diez niños sanos sirvieron como controles. Las muestras del moco se obtuvieron por barrido del piso de la nariz y del meato inferior. El material fue extendido en porta-objetos, fijado y coloreado por el método de Hansel. Las muestras de mucosa nasal fueron obtenidas del cornete inferior por medio de una cureta plástica descatable (Rhino-probe), extendidas sobre un porta-objetos, fijados y coloreados con Wright-Giemsa. La eficiencia del diagnóstico de la citología de las secreciones nasales, fue similar al de la mucosa, excepto en pacientes menores de un año de edad. Fue mejor la correlación entre atopía y citología nasal cuando ésta fue positiva tanto en las secreciones como en la mucosa