Efficacy of curcumin in the treatment of experimental vulvovaginal candidiasis

BackgroundCandida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported.AimsDue to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis.MethodsThe anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model.ResultsCurcumin showed minimum inhibitory concentration values of 125–1000 μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses.ConclusionsCurcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis.     

Titanium with nanotopography induces osteoblast differentiation through regulation of integrin αV

Topographical modifications of titanium (Ti) at the nanoscale level generate surfaces that regulate several signaling pathways and cellular functions, which may affect the process of osseointegration. Here, we investigated the participation of integrin αV in the osteogenic capacity of Ti with nanotopography. Machined titanium discs (untreated) were submitted to treatment with H₂SO₄/H₂O₂ to produce the nanotopography (nanostructured). First, the greater osteogenic capacity of the nanotopography that increased osteoblast differentiation of mesenchymal stem cells compared with untreated topography was shown. Also, the nanostructured surface increased (regulation ≥ 1.9-fold) the gene expression of 6 integrins from a custom array plate utilized to evaluate the gene expression of 84 genes correlated with cell adhesion signaling pathway, including integrin αV, which is involved in osteoblast differentiation. By silencing integrin αV in MC3T3-E1 cells cultured on nanotopography, the impairment of osteoblast differentiation induced by this surface was observed. In conclusion, it was shown that nanotopography regulates the expression of several components of the cell adhesion signaling pathway and its higher osteogenic potential is, at least in part, due to its ability to upregulate the expression of integrin αV. Together with previous data that showed the participation of integrins α1, β1, and β3 in the nanotopography osseoinduction activity, we have uncovered the pivotal role of this family of membrane receptors in the osteogenic potential of this surface.     

Characterization of Rhodnius neglectus from two regions of Brazil using isoenzymes, genitalia morphology and morphometry

Among the triatomines considered as secondary in the epidemiology of Chagas disease, Rhodnius neglectus is frequently captured in artificial ecotopes, especially peridomiciliary ones, rarely producing colonies indoors. Nevertheless, the presence of breeding colonies in houses was unquestionably demonstrated in some areas of the State of Goiás, Brazil. Previous isoenzyme comparisons of this species with morphologically close triatomines, such as R. prolixus, R. robustus or R. nasutus, did not produce definitive conclusions because of doubt about the geographical origin of the R. neglectus. We present here, for the first time, the isoenzyme profile of topotypes of R. neglectus. In addition, wild caught specimens from the type locality, Uberaba (Minas Gerais, Brazil), were compared to wild caught specimens from Jaraguá (Goiás, Brazil), where R. neglectus is more frequently reported invading houses. We used isoenzyme, morphology and morphometry analysis. Neither morphological nor enzymatic differences were found between areas, but metric, size-related divergence was evidenced between them.     

Agrobacterium tumefaciens-mediated genetic transformation of the entomopathogenic fungus Beauveria bassiana

Agrobacterium tumefaciens-mediated transformation (agro-transformation) was successfully applied to the entomogenous fungus Beauveria bassiana. Conidia of B. bassiana were transformed to hygromycin B resistance using the hph gene of Escherichia coli as the selective trait, under the control of a heterologous fungal promoter and the Aspergillus nidulans trpC terminator. The efficiency of transformation was up to 28 and 96 transformants per 10(4) and 10(5) target conidia, respectively, using three distinct vectors. High mitotic stability of the transformants (80-100%) was demonstrated after five successive transfers on a nonselective medium. Abortive transformants were observed for all the hph(r) vectors used. Putative transformants were analysed for the presence of the hph gene by PCR and Southern analysis. The latter analysis revealed the integration of two or more copies of the hph gene in the genome. The agro-transformation method was found to be effective for the isolation of B. bassiana hygromycin resistant transformants and may represent a useful tool for insertional mutagenesis studies in this fungus.     

Ketogenic Diet Increases Glutathione Peroxidase Activity in Rat Hippocampus

Ketogenic diets have been used in the treatment of refractory childhood epilepsy for almost 80 years; however, we know little about the underlying biochemical basis of their action. In this study, we evaluate oxidative stress in different brain regions from Wistar rats fed a ketogenic diet. Cerebral cortex appears to have not been affected by this diet, and cerebellum presented a decrease in antioxidant capacity measured by a luminol oxidation assay without changes in antioxidant enzyme activities—glutathione peroxidase, catalase, and superoxide dismutase. In the hippocampus, however, we observed an increase in antioxidant activity accompanied by an increase of glutathione peroxidase (about 4 times) and no changes in lipoperoxidation levels. We suggest that the higher activity of this enzyme induced by ketogenic diet in hippocampus might contribute to protect this structure from neurodegenerative sequelae of convulsive disorders.     

Molecular mapping in tropical maize (Zea mays L.) using microsatellite markers. 2. Quantitative trait loci (QTL) for grain yield, plant height, ear height and grain moisture

A previous genetic map containing 117 microsatellite loci and 400 F(2) plants was used for quantitative trait loci (QTL) mapping in tropical maize. QTL were characterized in a population of 400 F(2:3) lines, derived from selfing the F(2) plants, and were evaluated with two replications in five environments. QTL determinations were made from the mean of these five environments. Grain yield (GY), plant height (PH), ear height (EH) and grain moisture (GM) were measured. Variance components for genotypes (G), environments (E) and GxE interaction were highly significant for all traits. Heritability was 0.69 for GY, 0.66 for PH, 0.67 for EH and 0.23 for GM. Using composite interval mapping (CIM), a total of 13 distinct QTLs were identified: four for GY, four for PH and five for EH. No QTL was detected for GM. The QTL explained 32.73 % of the phenotypic variance of GY, 24.76 % of PH and 20.91 % of EH. The 13 QTLs displayed mostly partial dominance or overdominance gene action and mapped to chromosomes 1, 2, 7, 8 and 9. Most QTL alleles conferring high values for the traits came from line L-14-4B. Mapping analysis identified genomic regions associated with two or more traits in a manner that was consistent with correlation among traits, supporting either pleiotropy or tight linkage among QTL. The low number of QTLs found, can be due to the great variation that exists among tropical environments.