Tripanocide and antibacterial activity ofAlvaradoa subovata Cronquist extracts / Actividad tripanocida y antibacteriana de extractos de Alvaradoa subovata Cronquist

We studied antioxidant, antibacterial and tripanocide activities of Alvaradoa subovata extracts. The ethanolic extracts showed the greatest DPPH radical scavenging capacity, especially that of bark with an IC50 = 4.7 +/- 0.18 ug/mL. Wood dichloromethane extract displayed growth inhibition of the phytopathogenic bacteria Xanthomona axonopodis in the disk diffusion assay and showed a MIC value of 100 ug/ml. It also showed growth inhibition of Trypanosoma cruzi (IC50 = 0.063 +/- 0.003 mg/mL). A fraction of this extract, which has emodin as the main component, showed tripanocide activity (60 percent of growth inhibition at 100 ug/mL). The main compounds in wood dichloromethane extract were anthraquinones, identified as chrysophanol and emodin, and coumarins, of which scopoletin was identified. These three compound s could serve as analytical markers of the extract. The results of this study show that wood extract of A. subovata constitute a source of bioactive compounds such as antiparasitic and pesticides agents.

En el presente trabajo se estudió la actividad antioxidante, antibacteriana y tripanocida de extractos de Alvaradoa subovata. La mayor actividad depuradora de radicales libres se observó en el extracto etanólico de corteza (CI50 = 4.7 +/- 0.18 ug/mL). El extracto en diclorometano de madera inhibió el crecimiento de la bacteria fitopatógena Xanthomona axonopodis con una CIM = 100 ug/mL. El mismo extracto mostró inhibición del crecimiento de Trypanosoma cruzi (CI50 = 0.063 +/- 0.003 mg/mL). Una fracción de este extracto (100 ug/mL), cuyo componente mayoritario es emodina, inhibió en un 60 por ciento el crecimiento del parásito. Los compuestos mayoritarios detectados en el extracto de madera fueron antraquinonas, entre las cuales se identificaron emodina y crisofanol, y la cumarina escopoletina. Estos tres compuestos podrían servir como marcadores analíticos del extracto. Los resultados de este trabajo muestran que los extractos de A. subovata constituyen una fuente de compuestos bioactivos con potencial como antiparasitarios y plaguicidas.

Tolerance to a rice hydrolysate formula in children allergic to cow's milk and soy.

BACKGROUND: Even hydrolysed cow's milk formulae may retain residual allergens and there are few nutritional options for children with cow's milk allergy (CMA) who also react to soy. OBJECTIVE: To assess clinical tolerance to a rice-based hydrolysate in children with such a clinical presentation. PATIENTS AND METHODS: Eighteen children (six girls and 12 boys; median age 5 years; range 1-9 years) with CMA, who developed clinical reactions to a soy-based formula after 2-18 months' treatment, were recruited between January 1998 and June 1999. Clinical evaluation was by skin prick test (SPT) with cow's milk, casein, lactalbumin, soy and rice allergen extracts, fresh cow's milk, soy and hydrolysated rice formula (HRF). Serology was investigated by CAP system technology and immunoblotting. Assessment of the rice formula was carried out by double-blind, placebo-controlled food challenge with rice hydrolysate. RESULTS: Thirteen children had positive SPT to casein, 10 to lactalbumin, eight to rice and two to rice hydrolysate. Positive serology was found in all patients' sera tested with cow's milk, with soy in 13 sera and with rice in seven. Double-blinded, placebo-controlled challenge with an HRF was negative in all cases. CONCLUSIONS: Children allergic to cow's milk and soy tolerate an HRF clinically. This suggests that rice hydrolysate may be used as a protein source for children with multiple food-induced reactions.

Severe anaphylaxis induced by latex as a contaminant of plastic balls in play pits.

BACKGROUND: Latex causes anaphylaxis in specific contexts among children. We present 2 cases that show that severe reactions may occur in everyday circumstances with latex as a contaminant. OBJECTIVE: Because 2 cases of severe reactions to latex suggested similar circumstances of exposure, we investigated the immediate environment in which episodes occurred. METHODS: A 5-year-old girl presented to our casualty department with anaphylaxis after playing in a ball pit filled with approximately 10-cm diameter plastic balls in an American-style fast-food outlet. Two months later, a 9-year-old boy had severe anaphylaxis followed by an asthma attack with loss of consciousness while playing in the playpen of a different outlet belonging to the same company. Latex sensitization was confirmed in both cases by means of skin prick testing, latex glove skin prick testing, and 1-glove finger testing. Immunoblotting of elutions from a ball, the natural rubber latex foam pit lining, and its polyvinyl chloride sheet were performed. RESULTS: In the girl's immunoblot high levels of IgE specific to Hev b 4, Hev b 7, and Hev b 2 were found. The boy's immunoblot showed positivity to Hev b 7. The polyvinyl chloride ball sample showed a high concentration of specific Hevea species allergen similar to that of the foam layer sample. CONCLUSION: Severe anaphylaxis can result from contact with latex proteins as a contaminant, rather than as a component, of play area ball pits and therefore outside the reported settings. Emergency health care workers should be aware of this kind of risk. A latex-reduced environment might prevent potentially severe reactions in young customers of fast-food outlets.

Carob is not allergenic in peanut-allergic subjects.

BACKGROUND: The antigenic potential of proteins from the carob bean, a member of the legume family used as a food additive, have not so far been investigated and legumes share antigenic proteins with peanut, a potent trigger of anaphylaxis. OBJECTIVE: To assess the carob protein determinants of sensitization in peanut-allergic children. METHODS: In a prospective, double-blind, placebo-controlled study 12 patients (median age 9.5 years) with a history of hyperreactivity to peanut (anaphylaxis) were assessed. Skin prick tests with a commercial peanut allergen, raw carob pulp, raw and cooked carob cotyledon formula were used to confirm the history. RAST for peanuts and cooked carob were used to evaluate sensitization to these proteins. Carob-specific IgE were identified by immunoblotting analyses. Allergic reactivity was evaluated during double-blind placebo-controlled food challenges (DBPCFC; 5.5 g carob extract and cooked carob cotyledon formula). RESULTS: Peanut allergen-induced skin prick test positivity in all children (confirmed during double-blinded challenge in 6/12 patients), carob pulp in 3/12 patients, raw carob bean in 6/12, and cooked carob cotyledon formula in none. RAST were positive for peanut in all cases but negative for carob beans in 9/12 cases. Immunoblot analyses found peanut-specific IgE in all cases and raw carob bean-specific IgE in eight cases. Carob allergens were identified in the 17.5, 48, and 66 kDa MW bands. The least allergenic density was found for cooked carob proteins. There was no clinical reactivity with either raw or cooked carob during DBPCFC. CONCLUSIONS: These data suggest that carob-specific sensitization, apparent both in vitro and in SPTs, can be concordant with peanut allergy and that cooked carob can be ingested by children who are allergic to peanuts. That heat-processing deactivates carob protein allergenicity has dietary implications for polyallergic children.