Screening African rice (Oryza glaberrima) for tolerance to abiotic stresses: I. Fe toxicity.

Iron (Fe) toxicity is recognized as one of the most widely spread soil constraints for rice production especially in West Africa. Oryza glaberrima the cultivated rice species that originated from West Africa is well-adapted to its growing ecologies. The aim of this study was to identify the promising O. glaberrima accessions tolerant to Fe toxicity from the 2106 accessions held at the AfricaRice gene bank. The screenings were conducted over a four-year period and involved evaluating the entries under Fe-toxic field conditions in West Africa, selecting good yielding accessions and repeating the testing with newly selected lines. Three accessions (TOG 7206, TOG 6218-B and TOG 7250-A) were higher yielding than O. sativa checks under stress but with similar yields under control conditions. These accessions yielded over 300 g/m2 under both Fe toxicity and control conditions. In conclusion, these materials could be used as donors in breeding programs for developing high yielding rice varieties suited to Fe toxicity affected areas in West Africa.

[Correlation of the manifestations of tuberculosis and the degree of immunosuppression in patients with HIV]. / Corrélations des manifestations de la tuberculose pulmonaire avec le degré d'immunodépression au VIH.

CONTEXT: Correlation of the manifestations of tuberculosis and the degree of immunosuppression in patients with HIV. BACKGROUND: The advent of HIV has contributed to the increase in the number of people with tuberculosis. The clinical and paraclinical of TB/HIV co-infected are polymorphic and function of immune status. OBJECTIVES: To determines the clinical and paraclinical characteristics of TB related to different levels of CD4 lymphocytes. METHODOLOGY: A retrospective case series based on analysis of 450 patients with both TB/HIV co-infections. It focused on the records of patients with pulmonary smear-positive (TPM +) with a positive HIV status. The effect of immunosuppression was analyzed in groups based on the CD4 count (<200/mm(3), of 200-350/mm(3) and>350/mm(3)), in a chronological fashion from April to September 2010 until there were 150 patients in each CD4 group. RESULTS: Among the 450 patients, 71.1% were between 25 and 45years old. The clinical signs were more significant as the level of CD4 fell. The clinical signs were predominantly fever (93%) and weight loss (62.7%). Pulmonary cavitation (59.3%), infiltrates (38.7%) and the location of the lesions at the lung apex (72%) were more common in the third group patients. By contrast, extra pulmonary lesions (mediastinal lymphadenopathy, pleurisy) and normal x-ray (9.3%) were more frequent in patients of the first group. The scarcity of cavitations (22.3% compared to 59.3% CD4>350) and the increase in associated lesions became more marked if patients were immunocompromised. Hematologic, hepatic, renal disorders were more frequent and severe in the most immunocompromised patient group. CONCLUSION: HIV-associated tuberculosis has an atypical clinical, radiological, biological presentation and is more severe when there is significant immunosuppression.

Evaluation of the Bronchorelaxant, Genotoxic, and Antigenotoxic Effects of Cassia alata L.

Aqueous-ethanolic extract of Cassia alata (AECal) and its derived fractions obtained through liquid-liquid fractionation were evaluated for their bronchorelaxant, genotoxic, and antigenotoxic effects. Contractile activity of rats' tracheas in the presence of tested materials, as well as its modifications with different inhibitors and blockers, was isometrically recorded. The antigenotoxic potential of AECal was evaluated on cyclophosphamide- (CP-) induced genotoxicity in the rat. Animals were pretreated with the extract, then liver comet assay was performed. AECal and its chloroformic fractions (CF-AECal) relaxed the contraction induced by Ach, but both were significantly less potent in inhibiting contraction induced by KCl (30 mM; 80 mM). Propranolol, indomethacin, L-NAME, methylene blue, and glibenclamide did not modify the relaxant effect of CF-AECal. TEA altered the response of trachea to CF-AECal. CF-AECal caused a rightward shift without affecting the E max in cumulative concentration-response curves of Ach only at low concentrations. In animals pretreated with the extract, the percentage of CP-induced DNA damage decreased. Our results suggest that (1) muscarinic receptors contribute at least in part to the relaxant effects of CF-AECal; (2) CF-AECal interferes with membrane polarization; and (3) AECal is not genotoxic in vivo and contains chemopreventive phytoconstituents offering protection against CP-induced genotoxicity.

In vitro antioxidant, lipoxygenase and xanthine oxidase inhibitory activities of fractions from Cienfuegosia digitata Cav., Sida alba L. and Sida acuta Burn f. (Malvaceae).

In this study polyphenol content, antioxidant activity, lipoxygenase (LOX) and Xanthine Oxidase (XO) inhibitory effects of n-hexane, dichloromethane, ethyl acetate and n-butanol fractions of aqueous acetone extracts from S. alba L., S. acuta Burn f and Cienfuegosia digitata Cav. were investigated. The total phenolics, flavonoids, flavonols and total tannins were determined by spectrophotometric methods using Folin-ciocalteu, AlCl3 reagents and tannic acid, respectively. The antioxidant potential was evaluated using three methods: inhibition of free radical 2,2-diphenyl-1-picrylhydramzyl (DPPH), ABTS radical cation decolorization assay and Iron (III) to iron (II) reduction activity (FRAP). For enzymatic activity, lipoxygenase and xanthine oxidase inhibitory activities were used. This study shows a relationship between polyphenol contents, antioxidant and enzymatic activities. Present results showed that ethyl acetate and dichloromethane fractions elicit the highest polyphenol content, antioxidant and enzymatic activities.