Nádia R. Barbosa

Antioxidant and cytotoxic activities of Centella asiatica (L) Urb.

In the present study, the phenolic (Folin-Dennis) and flavonoid (colorimetric assay) constituents, antioxidant [2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) assay] and cytotoxic activities of an aqueous extract (AE) of Centella asiatica leaves were investigated. The aqueous extract (50 g/L) was obtained by infusion followed by cold maceration for 24 h. The levels of phenolic and flavonoid compounds were 2.86 g/100 g and 0.361 g/100 g, respectively. The AE showed elevated DPPH scavenging activity, with an IC50 value of 31.25 μg/mL. The AE had a promising activity against mouse melanoma (B16F1), human breast cancer (MDA MB-231) and rat glioma (C6) cell lines, with IC50 values of 698.0, 648.0 and 1000.0 μg/mL, respectively. A positive correlation was established between the level of flavonoids, antioxidant and antitumor activities.

Antiulcerogenic and anti-inflammatory activities of the essential oil from Pterodon emarginatus seeds

Objectives The objective of this work was to investigate the antiulcerogenic and anti‐inflammatory activities of the essential oil from Pterodon emarginatus seeds.

Atividades antimicrobiana e leishmanicida das sementes de Pterodon emarginatus Vogel

The present work investigated the antimicrobial and leishmanicidal activities of seeds of Pterodon emarginatus. The tests of diffusion in agar (10, 25 and 50 mg) and determination of minimum inhibitory concentration (MIC) were performed using essential oil (EO) obtained from seeds using the standard microorganisms: Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 90271, Escherichia coli ATCC 10530 and Candida albicans ATCC 10231. Leishmanicidal activity of the EO and fractions (6.25 - 100 µg/ml) obtained of seeds of P. emarginatus was evaluated in vitro using L. amazonensis and L. chagasi promastigote forms. The EO inhibited the growth of S. aureus (MIC = 2.5 mg/ml). The hexane (IC50 = 50.06 µg/ ml) and butanol (IC50 = 46.65 µg/ml) fractions showed activity against L. amazonensis promastigote forms, but did not against L. chagasi promastigote forms. The results indicate that the bioactive molecules present in the seeds of P. emarginatus can be used as prototype for the development of drug and/or as source pharmaceutical material.

Análise retrospectiva das intoxicações admitidas no hospital universitário da UFJF no período 2000-2004

Poisonings may have their consequences minimized by the acquisition of knowledge concerning its etiologies, evolutions and means of prevention. In Brazil, the progressive increase of toxic emergencies justifies the acquisition and analysis of regional and decentralized data concerning toxic emergencies. The aim of this retrospective and descriptive study was to evaluate data on the toxicology occurrence registered at the University Hospital/UFJF from 2000 to 2004. Data were collected using a structured instrument which comprised: age range, gender, profession, average hospitalization time, etiology and possible reasons for the intoxication, drug categories, where the patients live and the most important exposure route to the poisonous agent. The possible relationship among the data was also examined. The profile found for poisoning in the 50 cases analyzed, was that accidents are more common from 0 to 5 years old (24%) and male gender (68%), the majority of the cases happened in the city of Juiz de Fora (78%) and oral exposure. The most important poisonous agents were found to be the psychotropics (60%). Definition of a profile helps promoting educative activities and expands poisoning prevention campaigns by public health agencies. Therefore, these facts strengthen the importance of an Information Service net to prevent and reduce intoxications and the irrational use of drugs.

Synthesis and antimicrobial activity of amphiphilic carbohydrate derivatives

N-monoalkylated diamines were synthesised and treated with D-ribonolactone or D-gluconolactone. The resulting aldonamides were evaluated for their antimicrobial activity against S. aureus, E. coli, M. tuberculosis and C. albicans. Two hydrazides were also prepared from ribonohydrazide and their biological activity was compared to their amide analogues. All the ribono-derivatives displayed moderated antitubercular activity, and some of them were also active against S. aureus.

Leishmania amazonensis : Xylitol as inhibitor of macrophage infection and stimulator of macrophage nitric oxide production

Xylitol is a sugar alcohol being explored for clinical uses. The aim was to evaluate the effects of xylitol on Leishmania amazonensis-infected J774A.1 macrophages. Macrophages were infected with L. amazonensis for 3h, washed and incubated with 2.5 or 5.0% xylitol for 24, 48, and 72 h at 37 degrees C. Infection indexes for macrophages incubated only in medium were compared to those treated with xylitol. Cell viability and nitric oxide production were determined each time. Xylitol did not affect L. amazonensis or J774A.1 cell viabilities. Xylitol at 5.0% stimulated nitric oxide production by macrophages at 72 h (p<0.01). At 2.5 and 5.0%, xylitol inhibited nitric oxide production by L. amazonensis at 48 h (p<0.05) when compared to control. Infection indexes were significantly lower at 72 h (p<0.05), (16.9% and 9.6%) in cells cultivated with 2.5 and 5.0% xylitol, respectively, compared to control (38.4%). Results suggest a potential leishmanicidal action of the xylitol on infected macrophages.