Determination of insulin-like growth factor-I reference values using an immunoradiometric assay in a Brazilian adult population.

Background: Serum levels of total insulin-like growth factor I (IGF-I) reflect endogenous growth hormone (GH) secretion in healthy adults, which makes it a good diagnostic marker for screening of GH-related disorders. Studies also have supported a possible relation between IGF-I levels and the risk and prognostic for some malignancies, besides a relation between IGF-I levels and mortality. Objective: As the determination of the IGF-I normal values for local populations is strongly desired, the aim of this investigation was to determine reference values for IGF-I using an immunoradiometric assay (IRMA) in an adult Brazilian population of Rio de Janeiro city, since there is no other study using this methodology in Brazilian population, and that this method is widely used in Brazil and worldwide. Materials and Methods: The study included samples of blood taken from 484 healthy subjects (251 men and 233 women) aged 18-70. The subjects agreed with this study, approved by the Ethical Committee of the Instituto Estadual de Hematologia Arthur de Siqueira Cavalcanti, Rio de Janeiro, Brazil. The samples were analyzed using a Diagnostic System Laboratories kit. For data analysis, age- and sex-specific figures were fitted after transformation of IGF-I values. Results: In adulthood, a slow age-dependent decrease was found. There was no significant difference in IGF-I values between men and women. Conclusion: This study established age-specific IGF-I reference values, for a healthy Brazilian adult population, determined by a widely IGF-I, IRMA used currently in Brazil.

Biological effects of an aqueous extract of Salix alba on the survival of Escherichia coli AB1157 cultures submitted to the action of stannous chloride

Stannous chloride (SnC12) is used in nuclear medicine as a reducing agent to obtain technetium-99m-radiopharmaceuticals. It have been reported that natural products might reduce the genotoxic and cytotoxic effects related to SnC12. This work evaluated the biological effects of an aqueous extract of Salix alba on the survival of Escherichia coli (E. coli) AB1157 (wild type) cultures submitted to the action of SnC12. E. coli AB1157 cultures (exponential growth phase) were collected by centrifugation, washed and resuspended in 0.9 percentNaCl. Samples were incubated in water bath shaker with: (a) SnC12 (25mg/ml), (b)Salix alba extract(11.6mg/ml) and (c)SnC12(25mg/ml) + Salix alba extract (11.6mg/ml). Incubation with 0.9 percent NaCl was also carried out (control). At 60 min intervals, aliquots were withdrawn, diluted, spread onto Petri dishes with solid LB medium and incubated overnight. The colonies formed were counted and the survival fractions calculated. The extract was not able to protect the E. coli cultures against the lesive action of SnC12. The extract also did not interfere with the survival of the cultures. It suggested that the substances present in the Salix alba aqueous extract did not interfere strongly with cellular metabolism and did not alter the survival fractions of E. coli AB 1157. It is speculated that this extract cannot interfere with the generation of free radicals, the possible main agent responsible for SnC12 lesive action.

Influence of an aqueous extract of Hypericum perforatum (Hypericin) on the survival of Escherichia coli AB1157 and on the electrophoretic mobility of pBSK plasmid DNA / Influência de um extrato aquoso de Hypericum perforatum (Hipericina) na sobreviência de Escherichia coli AB1157 e na mobilidade eletroforética de DNA plasmidial pBSK

Hiperico (Hypericum perforatum or St John's worth) has been widely used as an herbal medicine to treat depression. Hypericin is the main chemical compound of hiperico. Stannous chloride (SnCl2) is the most used reducing agent in nuclear medicine. The aim of this work was to verify the effect of a hiperico extract on the survival of Escherichia coli AB1157 and on the plasmid DNA topology. Exponentially E. coli AB1157 cultures were incubated with SnCl2 in the presence or absence of hypericin. Aliquots were spread onto Petri dishes containing solidified rich medium, the colonies units were counted after overnight and the survival fraction was calculated. Plasmid DNA samples were incubated with SnCl2 in presence or absence of hypericin extract during 40 minutes, 0.8 percent agarose gel electrophoresis was performed, the gel was stained with ethidium bromide and the plasmid topological forms (bands) were visualized. The results revealed that hiperico extract is neither capable of altering the survival of E. coli cells nor the plasmid DNA topology but it may have protected these cells against the SnCl2 action. The data suggest absence of cytotoxic and genotoxic effects of the aqueous hiperico extract and a protective effect on E. coli cells against the action of SnCl2.

Hipérico (Hypericum perforatum or St John's worth) tem sido usado como uma planta medicinal para tratar a depressão. Hipericina é o principal componente do hipérico. O cloreto estanoso (SnCl2) é o agente redutor mais utilizado em medicina nuclear. O objetivo desse trabalho foi verificar o efeito de um extrato de hipérico na sobrevivência de Escherichia coli AB1157 e na topologia do DNA plasmidial. Culturas de E. coli AB1157, em fase exponencial, foram incubadas com SnCl2 na presença ou ausência de hipericina. Alíquotas foram espalhadas em placas de Petri contendo meio sólido, as unidades formadoras de colônias foram contadas após incubação e as frações de sobrevivência calculadas. DNA plasmidial foi incubado com SnCl2 na presença ou ausência de hipericina durante 40 minutos, eletroforese em gel de agarose a 0,8 por cento foi realizada, o gel foi corado com brometo de etídio e as formas (bandas) topológicas do plasmídeo visualizadas. Os resultados revelaram que o extrato de hipérico não foi capaz de alterar a sobrevivência da cultura de E. coli e a topologia do DNA plasmidial, mas protegeu as bactérias contra a ação do SnCl2. Os resultados sugerem ausência de efeitos citotóxicos e genotóxicos do extrato aquoso do hipérico e um efeito protetor nas células de E. coli contra a ação do SnCl2.

Osmotic and morphological effects on red blood cell membrane: action of an aqueous extract of Lantana camara / Efeitos osmótico e morfológico na membrana de hemácias: ação de um extrato aquoso de Lantana camara

The Lantana camara ("cambara de espinho") leaves infusions are used popularly in some countries to treat gastrointestinal diseases. Osmotic fragility assay and morphometric analysis have been used to verify the interaction of drugs with the membrane of red blood cells (RBC). The aim of this work was to evaluate the effects of an aqueous extract of Lantana camara on the osmotic fragility and on the morphology of RBC. Blood samples were treated with extract of Lantana camara (10 mg/mL), osmotic fragility assay and morphological analysis were carried out. In the presence of the extract, the data obtained indicated (i) a significant (p < 0.05) increase of hemolysis and (ii) modifications on the morphology of RBC. These effects of the Lantana camara may be associated with some pharmacological properties of the chemical compounds of this studied extract.

As infusões de folhas de Lantana camara (cambara-de-espinho) são usadas popularmente em alguns países para tratar doenças gastrointestinais. O experimento de fragilidade osmótica e a análise morfométrica têm sido usados para verificar a interação de drogas com a membrana de hemácias. O objetivo deste trabalho foi avaliar os efeitos de um extrato aquoso de Lantana camara na fragilidade osmótica e na morfologia de hemácias. Amostras de sangue foram tratadas com extrato de Lantana camara (10 mg/mL), o ensaio de fragilidade osmótica e a análise morfológica foram realizadas. Na presença do extrato, os dados obtidos indicaram (i) um aumento significativo (p < 0,05) da hemólise e (ii) modificações na morfologia das hemácias. Estes efeitos da Lantana camara poderiam estar associados com algumas propriedades farmacológicas de compostos químicos do extrato estudado.

Assessment of effects of a formula used in the traditional Chinese medicine (Buzhong Yi Qi Wan) on the morphologic and osmotic fragility of red blood cells

Buzhong Yi Qi Wan (BYQW) is a combination of some medicinal herbs widely used in traditional Chinese medicine to treat blood, spleen and stomach disorders. Morphometric analysis and osmotic fragility assay have been used to evaluate changes on membrane integrity of red blood cells. The aim of this work was to evaluate the effect of an aqueous BYQW extract on the morphology and osmotic fragility of red blood cells. Blood samples were treated with BYQW extract, quantitative/qualitative morphological analysis and osmotic fragility assay were carried out against control groups treated with saline. The data obtained indicated no modification on morphology but osmotic fragility assay suggested a significant (p<0.05) increasing of hemolysis in red blood cells isolated from blood treated with aqueous BYQW extract. In conclusion, the aqueous BYQW extract could affect the membrane integrity decreasing the osmotic resistance but without altering the shape of red blood cells.

Buzhong Yi Qi Wan (BYQW) é uma combinação de algumas ervas medicinais amplamente usada na medicina tradicional chinesa para tratar o sangue, baço e desordens do estômago. A análise morfométrica e o ensaio de fragilidade osmótica têm sido usados para avaliar alterações na integridade da membrana de hemácias. O objetivo deste trabalho foi avaliar os efeitos de um extrato aquoso de BYQW na morfologia e na fragilidade osmótica de hemácias. Amostras sangüíneas foram tratadas com o extrato de BYQW, análise morfológica quantitativa/qualitativa e o ensaio de fragilidade osmótica foram realizados e comparados com grupo controle tratado com salina. Os dados obtidos indicaram ausência de modificações na morfologia, mas o ensaio de fragilidade osmótica sugeriu um aumento significativo (p<0,05) da hemólise em hemácias isoladas de sangue tratado com extrato aquoso de BYQW. Em conclusão, o extrato aquoso de BYQW poderia afetar a integridade da membrana diminuindo a resistência osmótica sem alterar a forma das hemácias.

An aqueous extract of Pfaffia sp. does not alter the labeling of blood constituents with technetium-99m and the morphology of the red blood cells

Plants have been used for the human beings as food, as additives and/or as medicines. There are controversies about the biological effects of several natural products and, it is worthwhile to try to develop experimental assays to evaluate properties of extracts of plants. Pfaffia sp. is utilized in popular medicine and various properties have been attributed to its extract. Red blood cells (RBC) and plasma proteins are labeled with technetium-99m (Tc-99m) and this labeling procedure depends on a reducing agent and stannous ion is usually used. There are reports that drugs can alter the labeling of blood elements with Tc-99m. We have evaluated the influence of a Pfaffia sp. extract on the labeling of blood constituents with Tc-99m and on the morphology of RBC. Blood was incubated with an aqueous extract of Pfaffia sp., stannous chloride and Tc-99m. Samples were centrifuged and plasma and blood cells were separated and also precipitated with trichloroacetic acid. Soluble and insoluble fractions were separated. The results did not show alteration in the uptake of radioactivity and no modifications on the shape of the RBC in presence of Pfaffia sp. Once this labeling process depends on a reducing agent, probably, this extract has compounds with anti-oxidant properties as already described elsewhere, that could protect the stannous ions against the oxidation process. This fact would aid the labeling process of blood elements with Tc-99m.