Comparative study of disk diffusion and microdilution methods for evaluation of antifungal activity of natural compounds against medical yeasts Candida spp and Cryptococcus sp

Antifungal activity of natural products has been tested by adapting methods designed for synthetic drugs. In this study, two methods for the determination of antifungal activity of natural products, agar diffusion and broth microdilution, the CLSI reference methods for synthetic drugs, are compared and discussed. The microdilution method was more sensitive. The minimal inhibitory concentrations (MIC) of crude extracts, fractions and pure substances from different species of the plant families Piperaceae, Rubiaceae, Clusiaceae, Fabaceae and Lauraceae, from the Biota project, were determined. Antifungal activities against Candida albicans, C.krusei, C.parapsilosis and Cryptococcus neoformans were produced by several samples.

Evaluation of micronuclei frequency in Tradescantia pallida pollen mother cells treated with ethanolic extracts isolated from Cryptocarya mandioccana, Cryptocarya moschata and Pterogyne nitens

Although herbal extracts contain several classes of compounds with pharmacological activity, they also present toxic substances with mutagenic effects. The aim of the present study was to verify the mutagenicity of Cryptocarya moschata, Cryptocarya mandioccana and Pterogyne nitens using micronucleus assay in pollen mother cells (tetrads) in Tradescantia pallida (Trad-MCN). T. pallida inflorescences were treated with different concentrations of ethanolic extracts from the selected plant species. For C. mandioccana C. moschata and P. nitens, Trad-MCN assays were carried out simultaneoulsly, followed by positive control (formaldehyde 10000 ppm), negative control (Hoagland's solution), and vehicle control (Tween 20 20% or DMSO 3%). MCN present in tetrads were quantified in 300 tetrads/inflorescence and the mean (%) and standard error (SE) were established for at least 10 inflorescences per treatment. The extracts demonstrated dose response mutagenicity (clastogenic/aneugenic effects), respectively, C. mandioccana (0.5, 1.0 and 2.0 mg/mL) and P. nitens (1.0 and 2.0 mg/mL) However, no mutagenic effect was observed to C. moschata at the concentrations evaluated in the present study. We can conclude that the C. mandioccana and P. nitens extracts demonstrated clastogenic/aneugenic effects in highest concentrations whereas C. moschata extract did not demonstrate the same effect. © 2006 Sociedade Brasileira de Toxicologia.

Myeloperoxidase inhibitory and radical scavenging activities of flavones from Pterogyne nitens

Two new flavone glucosides, nitensosides A and B (1, 2), together with four known compounds, sorbifolin (3), sorbifolin 6-O-β-glucopyranoside (4), pedalitin (5), and pedalitin 6-O-β-glucopyranoside (6) were isolated from Pterogyne nitens. Their structures were elucidated from 1D and 2D NMR analysis, as well as by high resolution mass spectrometry. All the isolated flavones were evaluated for their myeloperoxidase (MPO) inhibitory activity. The most active compound, pedalitin, exhibited IC 50 value of 3.75 nM on MPO. Additionally, the radical-scavenging capacity of flavones 1-6 was evaluated towards ABTS and DPPH radicals and compared to standard compounds quercetin and Trolox®. © 2008 Pharmaceutical Society of Japan.

Perspectivas de la agricultura y el desarrollo rural en las Américas: una mirada hacia América Latina y el Caribe, 2009

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Situación actual y política de apoyo a las pequeñas y medianas empresas industriales en Costa Rica

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Brazilian network for the surveillance of maternal potentially life threatening morbidity and maternal near-miss and a multidimensional evaluation of their long term consequences

Background. It has been suggested that the study of women who survive life-threatening complications related to pregnancy (maternal near-miss cases) may represent a practical alternative to surveillance of maternal morbidity/mortality since the number of cases is higher and the woman herself is able to provide information on the difficulties she faced and the long-term repercussions of the event. These repercussions, which may include sexual dysfunction, postpartum depression and posttraumatic stress disorder, may persist for prolonged periods of time, affecting women's quality of life and resulting in adverse effects to them and their babies. Objective. The aims of the present study are to create a nationwide network of scientific cooperation to carry out surveillance and estimate the frequency of maternal near-miss cases, to perform a multicenter investigation into the quality of care for women with severe complications of pregnancy, and to carry out a multidimensional evaluation of these women up to six months. Methods/Design. This project has two components: a multicenter, cross-sectional study to be implemented in 27 referral obstetric units in different geographical regions of Brazil, and a concurrent cohort study of multidimensional analysis. Over 12 months, investigators will perform prospective surveillance to identify all maternal complications. The population of the cross-sectional component will consist of all women surviving potentially life-threatening conditions (severe maternal complications) or life-threatening conditions (the maternal near miss criteria) and maternal deaths according to the new WHO definition and criteria. Data analysis will be performed in case subgroups according to the moment of occurrence and determining cause. Frequencies of near-miss and other severe maternal morbidity and the association between organ dysfunction and maternal death will be estimated. A proportion of cases identified in the cross-sectional study will comprise the cohort of women for the multidimensional analysis. Various aspects of the lives of women surviving severe maternal complications will be evaluated 3 and 6 months after the event and compared to a group of women who suffered no severe complications in pregnancy. Previously validated questionnaires will be used in the interviews to assess reproductive function, posttraumatic stress, functional capacity, quality of life, sexual function, postpartum depression and infant development. © 2009 Cecatti et al.

Políticas para el perfeccionamiento de la institucionalidad laboral en Costa Rica

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Implicaciones de la política macroeconómica, los choques externos y los sistemas de protección social en la pobreza, la desigualdad y la vulnerabilidad en América Latina y el Caribe: Costa Rica

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Entidades de gestión del agua a nivel de cuencas: experiencia de Argentina

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Indices of body fat distribution for assessment of lipodysthrophy in people living with HIV/AIDS

Background: Metabolic and morphological changes associated with excessive abdominal fat, after the introduction of Antiretroviral Therapy, increase the risk of cardiovascular disease in people living with HIV/AIDS(PLWHA). Accurate methods for body composition analysis are expensive and the use of anthropometric indices is an alternative. However the investigations about this subject in PLWHA are rare, making this research very important for clinical purpose and to advance scientific knowledge. The aim of this study is to correlate results of anthropometric indices of evaluation of body fat distribution with the results obtained by Dual-energy X-Ray Absorptiometry(DEXA) , in people living with HIV/AIDS. Methods. The sample was of 67 PLWHA(39 male and 28 female), aged 43.6+7.9 years. Body mass index, conicity index, waist/hip ratio, waist/height ratio and waist/thigh were calculated. Separated by sex, each index/ratio was plotted in a scatter chart with linear regression fit and their respective Pearson correlation coefficients. Analyses were performed using Prism statistical program and significance was set at 5%. Results: The waist/height ratio presented the highest correlation coefficient, for both male (r=0.80, p<0.001) and female (r=0.87, p <001), while the lowest were in the waist/thigh also for both: male group (r=0.58, p<0.001) and female group (r=0.03, p=0.86). The other indices also showed significant positive correlation with DEXA. Conclusion: Anthropometric indices, especially waist/height ratio may be a good alternative way to be used for evaluating the distribution of fat in the abdominal region of adults living with HIV/ADIS. © 2012 Segatto et al.; licensee BioMed Central Ltd.

Antibacterial activity of alkyl gallates against Xanthomonas citri subsp. citri

The plant-pathogenic bacterium Xanthomonas citri subsp. citri is the causal agent of Asiatic citrus canker, a seriousdisease that affects all the cultivars of citrus in subtropical citrus-producing areas worldwide. There is no curative treatment for citrus canker; thus, the eradication of infected plants constitutes the only effective control of the spread ofX. citri subsp. citri. Since the eradication program in the state of São Paulo, Brazil, is under threat, there is a clear risk of X. citri subsp. citri becoming endemic in the main orange-producing area in the world. Here we evaluated the potential use of alkyl gallates to prevent X. citri subsp. citri growth. These esters displayed a potent anti-X. citri subsp. citri activity similar to that of kanamycin (positive control), as evaluated by the resazurin microtiter assay (REMA). Thetreatment of X. citri subsp. citri cells with these compounds induced altered cell morphology, and investigations of the possible intracellular targets using X. citri subsp. citri strains labeled for the septum and centromere pointed to a commontarget involved in chromosome segregation and cell division. Finally, the artificial inoculation of citrus with X. citri subsp. citri cells pretreated with alkyl gallates showed that the bacterium loses the ability to colonize its host, which indicates the potential of these esters to protect citrus plants against X. citri subsp. citri infection. © 2013, American Society for Microbiology.

Free radical scavenging activity of Kielmeyera variabilis (Clusiaceae)

As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH (2,2-diphenyl-1- picrylhydrazyl-hydrate) and ABTS+ [2,2'-azinobis(3- ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL -1 for DPPH and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL -1 for ABTS+, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O- glucoside (3), and quercetin-3-O-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported. © 2013 by the authors.

Manejo integrado del recurso agua, con la perspectiva de los Principios de Dublín

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Assessment of the chemopreventive effect of casearin B, a clerodane diterpene extracted from Casearia sylvestris (Salicaceae)

Studies have shown that Casearia sylvestris compounds protect DNA from damage both in vitro and in vivo. Complementarily, the aim of the present study was to assess the chemopreventive effect of casearin B (CASB) against DNA damage using the Ames test, the comet assay and the DCFDA antioxidant assay. The genotoxicity was assessed by the comet assay in HepG2 cells. CASB was genotoxic at concentrations higher than 0.30μM when incubated with the FPG (formamidopyrimidine-DNA glycosylase) enzyme. For the antigenotoxicity comet assay, CASB protected the DNA from damage caused by H2O2 in the HepG2 cell line in concentrations above 0.04μM with post-treatment, and above 0.08μM with pre-treatment. CASB was not mutagenic (Ames test) in TA 98 and TA 102. In the antimutagenicity assays, the compound was a strong inhibitor against aflatoxin B1 (AFB) in TA 98 (>88.8%), whereas it was moderate (42.7-59.4%) inhibitor against mytomicin C (MMC) in TA 102. Additionally, in the antioxidant assay using DCFDA, CASB reduced reactive oxygen species (ROS) generated by H2O2. In conclusion, CASB was genotoxic to HepG2 cells at high concentrations; was protective of DNA at low concentrations, as shown by the Ames test and comet assay; and was also antioxidant. © 2012 Elsevier Ltd.

7-Hydroxycassine: A new 2,6-dialkylpiperidin-3-ol alkaloid and other constituents isolated from flowers and fruits of senna spectabilis (Fabaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)