RESUMO
OBJECTIVE: Exogenous natural surfactant (ENS) labeled with 99mTc shows an elevated lung specificity allowing the acquisition of high-quality images for ventilation scintigraphy. METHODS: The methods for 99mTc-ENS quality control (physical properties, pH determination, radiochemical studies, and biologic studies) were evaluated and validated. RESULTS: The physical properties of the nonradioactive precursor and of the radiopharmaceutical were analyzed as general descriptors of the product. The pH of the radiopharmaceutical was determined by using pH test papers, a method described and validated in the United States Pharmacopeia. Chromatographic studies performed using the acetone/Whatman-1 paper system were validated as a method to evaluate the radiochemical purity of the 99mTc-ENS. Biodistribution studies on rats after intratracheal administration were validated as a method to estimate the radiopharmaceutical biodistribution in humans. CONCLUSION: The proposed method for 99mTc-ENS quality control studies and stability studies was evaluated and validated following international standards.
Assuntos
Marcação por Isótopo/métodos , Pulmão/metabolismo , Surfactantes Pulmonares/farmacocinética , Tecnécio/farmacocinética , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Marcação por Isótopo/normas , Pulmão/diagnóstico por imagem , Taxa de Depuração Metabólica , Especificidade de Órgãos , Surfactantes Pulmonares/análise , Surfactantes Pulmonares/normas , Controle de Qualidade , Cintilografia , Compostos Radiofarmacêuticos/análise , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/normas , Ratos , Ratos Sprague-Dawley , Tecnécio/análise , Tecnécio/normas , Distribuição TecidualRESUMO
The iron bioavailability and acute oral toxicity in rats of a ferrous gluconate compound stabilized with glycine (SFG), designed for food fortification, was studied in this work by means of the prophylactic method and the Wilcoxon method, respectively. For the former studies, SFG was homogeneously added to a basal diet of low iron content, reaching a final iron concentration of 20.1 +/- 2.4 mg Fe/kg diet. A reference standard diet using ferrous sulfate as an iron-fortifying source (19.0 +/- 2.1 mg Fe/kg diet) and a control diet without iron additions (9.3 +/- 1.4 mg Fe/kg diet) were prepared in the laboratory in a similar way. These diets were administered to three different groups of weaning rats during 23 d as the only type of solid nourishment. The iron bioavailability of SFG was calculated as the relationship between the mass of iron incorporated into hemoglobin during the treatment and the total iron intake per animal. This parameter resulted in 36.6 +/- 6.2% for SFG, whereas a value of 35.4 +/- 8.0% was obtained for ferrous sulfate. The acute toxicological studies were performed in two groups of 70 female and 70 male Sprague-Dawley rats that were administered increasing doses of iron from SFG. The LD50 values of 1775 and 1831 mg SFG/kg body wt were obtained for female and male rats, respectively, evidencing that SFG can be considered as a safe compound from a toxicological point of view.
Assuntos
Compostos Ferrosos/metabolismo , Compostos Ferrosos/toxicidade , Alimentos Fortificados/toxicidade , Ferro/metabolismo , Animais , Disponibilidade Biológica , Feminino , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Microencapsulated ferrous sulfate (SFE-171) and ferric orthophosphate in Petit-Suisse cheese were examined for iron bioavailability by the prophylactic method. The iron sources were industrially added to different samples of Petit-Suisse cheese, which were mixed with other food components in our laboratory before use. A reference standard diet inclusive of nonmicroencapsulated ferrous sulfate and a control diet low in iron content were prepared in the laboratory. The final iron content in the fortified diets was approximately 15 mg Fe/kg diet. These diets were administered to weaning rats for 23 days. The iron bioavailability was evaluated as the ratio of iron incorporated into hemoglobin to oral iron intake, thereby being estimated as 62.6 +/- 8.8% for ferrous sulfate and 59.2 +/- 10.6% for SFE-171, which were significantly effective at p < 0.01 compared to 43.4 +/- 10.5% for ferric orthophosphate. It thus turned out that SFE-171 was stable through industrial processing with Petit-Suisse cheese as the food vehicle and served as an iron fortifier equal to ferrous sulfate in bioavailability.
Assuntos
Anemia Ferropriva/prevenção & controle , Queijo , Alimentos Fortificados , Hemoglobinas/química , Ferro da Dieta/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Queijo/análise , Composição de Medicamentos , Feminino , Compostos Férricos/farmacocinética , Compostos Ferrosos/farmacocinética , Fosfatidilcolinas/farmacocinética , Ratos , Ratos Sprague-Dawley , DesmameRESUMO
Gastrointestinal lesions have been extensively reported in wild and captive marine mammals. However, their etiology remains unclear. In humans and other animals, chronic gastritis and peptic ulcers have been associated with Helicobacter sp. Therefore, the aim of our study was to investigate the presence of Helicobacter sp. in the gastric juice, dental plaque, and saliva of marine mammals living in a controlled environment. Five dolphins (Tursiops gephyreus), one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), three sea lions (Otaria flavescens), two elephant seals (Mirounga leonina), and two fur seals (Arctocephalus australis) were studied. Saliva, dental plaque, and gastric juice samples were examined for Helicobacter sp. using polymerase chain reaction. None of the gastric juice or saliva samples were positive for Helicobacter sp. However, Helicobacter sp. DNA was detected in dental plaque from two dolphins, suggesting the oral cavity might be a reservoir of this bacterium.
Assuntos
Placa Dentária/veterinária , Golfinhos , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Animais , Animais de Zoológico , DNA Bacteriano/análise , Placa Dentária/microbiologia , Feminino , Suco Gástrico/química , Suco Gástrico/microbiologia , Gastrite/microbiologia , Gastrite/veterinária , Helicobacter/genética , Infecções por Helicobacter/microbiologia , Masculino , Reação em Cadeia da Polimerase/veterinária , Saliva/microbiologia , Focas VerdadeirasRESUMO
This review concerns the importance of zinc in growth, development, and cognitive function in children and the deleterious consequences of its deficiency on children's health. Possible strategies to overcome zinc deficiency and the results of some supplementation trials are discussed.
Assuntos
Desenvolvimento Infantil/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Crescimento/efeitos dos fármacos , Zinco/farmacologia , Zinco/fisiologia , Estatura/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Cognição/efeitos dos fármacos , Cognição/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Feminino , Crescimento/fisiologia , Humanos , Lactente , Lactação/metabolismo , Masculino , Gravidez , Zinco/deficiênciaRESUMO
OBJECTIVE: We investigated the iron bioavailability of microencapsulated ferrous sulfate (SFE-171) in a diet based on powdered milk by using the prophylactic method in rats. METHODS: The SFE-171 was added into fluid milk and industrially processed into powdered milk, which was then mixed in our laboratory with a normalized diet (17.2 +/- 2.1 mg Fe/kg). A reference standard diet using ferrous sulfate as iron-fortifying source (19.8 p+/- 2.9 mg Fe/kg) and a control diet without added iron (4.6 +/- 0.8 mg Fe/kg) were prepared in the laboratory in a similar way. These diets were administered to different groups of weaning rats for 28 d as the only solid nourishment. The iron bioavailability of the different sources was calculated as the relation between the mass of iron incorporated into hemoglobin during the treatment and the total iron intake per animal. RESULTS: The iron bioavailability values of SFE-171 and ferrous sulfate in the fortified diets were 41.6 +/- 6.6% and 42.6 +/- 4.2%, respectively; these results were significantly higher (P < 0.01) than the iron bioavailability of the control diet (28.8 +/- 8.1%). CONCLUSION: These results showed that iron-fortified powdered milk can be produced from fluid milk fortified with SFE-171. The bioavailability of SFE-171 in this rat model was not altered by the manufacturing process.
Assuntos
Anemia Ferropriva/prevenção & controle , Compostos Ferrosos/farmacocinética , Alimentos Fortificados/normas , Ferro da Dieta/sangue , Leite/química , Animais , Disponibilidade Biológica , Composição de Medicamentos , Feminino , Leite/metabolismo , Ratos , Ratos Sprague-Dawley , DesmameRESUMO
Iron deficiency is one of the most important nutritional problems in the world. The best method to overcome this problem is the fortification of foods with highly bioavailable iron. Fluid milk is a massive consumption food with an easy access and which is generally the only food intake during the first months of life. Therefore the fortification of fluid milk with highly biovalable iron and no detectable alterations of its sensorial characteristics was studied in the present work. This procedure was made possible using a new type of ferrous sulfate, stabilized and microencapsulated with soy lecithin (SFE-171). The iron concentration of the fortified milk is 12 mg per liter. In order study the iron absorption from milk fortifield with this product, SFE-171 was labeled with59 Fe and given to 29 volunteers with a normal iron status, each of which received an iron quantily of 3 mg in 250 ml of fluid milk. The average iron absorption was (10.2+4.7) per cent. This result shows that the iron given in this physiocochemical form has the advantage of a high biovailability and it is possible that this product will be the first attempt for an adequate solution of iron deficiency.
Assuntos
Adulto , Humanos , Masculino , Disponibilidade Biológica , Sulfato Ferroso , Ferro da Dieta/sangue , Leite Humano/química , Leite/química , Ciências da Nutrição , Anemia Ferropriva/prevenção & controleRESUMO
Iron deficiency is one of the most important nutritional problems in the world. The best method to overcome this problem is the fortification of foods with highly bioavailable iron. Fluid milk is a massive consumption food with an easy access and which is generally the only food intake during the first months of life. Therefore the fortification of fluid milk with highly biovalable iron and no detectable alterations of its sensorial characteristics was studied in the present work. This procedure was made possible using a new type of ferrous sulfate, stabilized and microencapsulated with soy lecithin (SFE-171). The iron concentration of the fortified milk is 12 mg per liter. In order study the iron absorption from milk fortifield with this product, SFE-171 was labeled with59 Fe and given to 29 volunteers with a normal iron status, each of which received an iron quantily of 3 mg in 250 ml of fluid milk. The average iron absorption was (10.2+4.7) per cent. This result shows that the iron given in this physiocochemical form has the advantage of a high biovailability and it is possible that this product will be the first attempt for an adequate solution of iron deficiency. (AU)