Ausência de mutagenicidade e antimutagenicidade do extrato obtido das flores do ipê roxo [Tabebuia impetiginosa (Mart. ex DC.) Standl.] / Absence of mutagenicity and antimutagenicity of the extract obtained from the flowers of "ipê roxo" Tabebuia impetiginosa (Mart. ex DC.) Standl

A Tabebuia impetiginosa, conhecida popularmente como ipê-roxo, é uma planta nativa das florestas tropicais chuvosas da América do Sul e Central. Componentes químicos obtidos da casca têm mostrado efeito terapêutico, como antiinflamatório, antifúngico e antibacteriano. Porém, pela falta de dados na literatura, pouco se sabe sobre os efeitos do extrato das flores. Assim, o objetivo do presente trabalho foi avaliar o potencial mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa, em três diferentes concentrações (100, 300 e 500 mg kg-1 p.c.) pelo teste do micronúcleo. Para o teste de mutagenicidade, a doxorrubicina (DXR, 90 mg kg-1 p.c.) foi utilizada como indutor de danos no DNA e para o teste de antimutagenicidade, os tratamentos com o extrato foram realizados simultaneamente com este agente químico. O sangue periférico dos animais foi coletado 24 horas após os tratamentos. A comparação da frequência de eritrócitos policromáticos (PCEs) em 400 eritrócitos/animal entre os diferentes grupos não demonstrou qualquer citotoxicidade do extrato. Em relação às frequências de micronúcleos em PCEs (PCEMNs), não foram observadas diferenças significativas entre os grupos tratados com as diferentes concentrações de extrato e o controle negativo. Da mesma forma, todos os grupos de animais que receberam os tratamentos simultâneo do extrato (100, 300 ou 500 mg kg-1 p.c.) com a DXR, apresentaram valores de PCEMNs muito próximos quando comparados com os dados observados no grupo de animais que recebeu somente a DXR. Esses resultados apresentados indicam ausência de efeito mutagênico e antimutagênico do extrato obtido das flores da T. impetiginosa em sistema teste in vivo.

T. impetiginosa, known as "ipê-roxo", is a plant native to tropical rain forests of Central and South Americas. Chemical compounds obtained from its bark have shown anti-inflammatory, antifungal and antibacterial therapeutic effect. However, due to the lack of data in the literature, little is known about the effects of its flower extract. Thus, the aim of this study was to evaluate the mutagenic and antimutagenic potential of the extract obtained from T. impetiginosa flowers at three different concentrations (100, 300 and 500 mg kg-1 p.c.) by the micronucleus test. For the mutagenicity test, doxorubicin (DXR, 90 mg kg-1 p.c.) was used as DNA-damage inducer, while for the antimutagenicity test, treatments with the extract were performed simultaneously with this chemical agent. The peripheral blood of animals was collected 24 hours after the treatments. The frequency of polychromatic erythrocytes (PCEs) in 400 erythrocytes/animal was compared among the different groups and showed no extract cytotoxicity. As regards the frequency of micronuclei in PCEs (PCEMNs), there were no significant differences between the groups treated with different concentrations of extract and the negative control. Similarly, all groups of animals that received the simultaneous extract treatments (100, 300 or 500 mg kg-1 p.c.) with DXR showed very similar values of PCEMNs when compared with the data observed for the group of animals that received DXR alone. These results indicate no mutagenic and antimutagenic effect of the extract obtained from T. impetiginosa flowers in the testing system in vivo.

Comparative study of the effects of vitamin C and bleomycin on smokers' and non-smokers' lymphocytes in clastogenicity assays.

Free radicals are products of metabolic reactions and of external factors that can injure different biological molecules. However, different antioxidant agents can prevent the action of these reactive species and the damage they cause. Vitamin C (VC) is an important micronutrient found in the diet, which presents defense mechanisms against the free radicals that challenge the cells of the organism. The objective of the present study was to investigate the effect of VC as a modulator of the damage induced in DNA by bleomycin (BLM) in lymphocytes from smokers and non-smokers. The difference in response to the mutagenic potential of BLM between smokers and non-smokers was also investigated. Peripheral blood lymphocyte cultures were treated simultaneously with BLM (20 microg/ml) and/or VC (100, 200, and 400 microg/ml) in the G2 phase of the cell cycle. The results obtained did not demonstrate a statistically significant difference in the response to the antitumor agent BLM between smokers and non-smokers. The data also showed that VC had no significant modulating effect on the frequency of chromosome aberrations induced by BLM in the cells of smokers and non-smokers under the experimental conditions used.

[Collection of autologous blood during pregnancy and fetal safety. Computer analysis of fetal heart rate]. / Predonazione di sangue autologo in corso di gravidanza e sicurezza fetale. Analisi computerizzata dell'attività cardiaca fetale.

BACKGROUND: This study aims at objectively evaluating the impact on the fetus of a sudden maternal blood withdrawal, through a computer analysis of the various aspects of the cardiotocographic pattern before and after one autologous blood unit predonation from near term pregnant women. METHODS: For the collection of cardiotocographic data, a Sonicaid Team fetal monitor was used; it is a monitoring system which uses Doppler ultrasound impulses and autocorrelates the received Doppler signals with varied signals of frequency, connected to Sonicaid System 8000, a program for "objective" cardiotocographic analysis according to the so-called Dawes-Redman criteria. RESULTS: From the statistic comparison of Non Stress Tests preceeding and following predonation, some statistically significant differences have sometimes emerged on the level of specific parameters. CONCLUSIONS: In particular, the general variation of fetal heart frequency and fetal reactivity resulted higher after predonation, even though they were within absolute normality, justifying the suspicion that the stress of autologous predonation practice might produce some indefinite disturbance to fetal activity/rest rhythm.

[Autologous blood collection in pregnancy. Prospective study]. / Predeposito di sangue autologo in gravidanza. Studio prospettico.

Autologous blood predonation during pregnancy, with the aim of autotransfusion after delivery, has gained increasing consensus over the last few years. However, there are still some controversial aspects. In particular, the cost/benefit ratio of institutionalizing the above mentioned practice would appear altogether unfavourable (too many women would be really in need of transfusion after delivery). The aim of the present study is to assess the results of our experience using autotransfusion in obstetrics. This longitudinal and prospective study was carried out on a sample of 29 pregnant women who donated 1 unit of blood during the last month of their pregnancy. Phlebotomy was preceded by a verification of the permitting conditions (Hb > or = 11 g/dl; Ht > or = 33%). Before, during and after phlebotomy, the patients underwent cardiotocographic monitoring and periodic observation of vital parameters. The hematologic parameters registered during the various test (before predeposit, before delivery, in puerpery) were statistically analysed. The hemochromo values appeared satisfactory in all cases at the time of admittance for labour. As a consequence of a hematic loss higher than usual at the moment of delivery, in many cases the hemoglobin values during puerpery did not enable us to exclude a priori the advisability of a transfusion. From the study we see how the cost/benefit ratio of the predeposit practice in obstetrics is less unfavourable than commonly thought.

[Autologous transfusion in obstetrics and fetal safety]. / Trasfusione autologia in ostetricia e sicurezza fetale.

It is common knowledge that for modern medicine transfusion therapy represents a precious resource and an often mandatory option. It is equally known that autohemotransfusion (or autologous transfusion) provides further advantages: certainty of blood availability when necessary, absence of transfusion reactions, elimination of the risk of infections that is still associated with the traditional homologous transfusions. In its most widespread application, autotransfusion provides for the donation of one or more units of autologous blood, mostly before elective surgery. Even in obstetrics the practice of autologous blood donation with the aim of autotransfusion is finding increasing employment. However, there are still controversial aspects and the need is pointed out for more authoritative verifications as refers to the alleged innocuity to the fetus of acute maternal blood loss. The present study was performed to contribute personal experience to a better definition of the possible interactions between autologous blood donation during pregnancy and unborn child welfare. To this end, 80 term pregnant women underwent fetal heart rate electronic monitoring before, during and after the donation of one unit of autologous blood. Both during and after the phlebotomy there were no cardiotocographic signs of fetal hypo-oxygenation. Even the non stress tests performed at a distance of 24 hours and those that were periodically repeated afterwards were normal, confirming the safety of autologous predonation during pregnancy. However, the authors think that in obstetrics it is still premature to consider the experimental phase of autotransfusion as definitively exhausted.