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BackgroundToxoplasmosis is a zoonosis caused by an obligate intracellular parasite, Toxoplasma gondii, which affects warm-blooded animals including humans. Its prevalence rates usually vary in different regions of the planet.MethodsIn this study, an analysis of the seroprevalence of toxoplasmosis among Brazilian students was proposed by means of IgG specific antibodies detection. The presence of anti-Toxoplasma gondii antibodies by indirect fluorescent antibody test (IFAT) was also evaluated in order to compare it with enzyme-linked immunosorbent assay (ELISA) and to assess the use of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and o-phenylenediamine dihydrochloride chromogens.ResultsThe IFAT method showed a seroprevalence of 22.3%. These results were similar to those obtained by ELISA (24.1%). The seroprevalence was directly estimated from the IgG avidity, which showed that in a sample of 112 students, three of them had acute infection, an incidence of 1.6% in the studied population.ConclusionIn this study, the use of different chromogenic substrates in immunoenzymatic ELISA assays did not display different sensitivity in the detection of T. gondii-reagent serum. The extrapolation of results to this population must be carefully considered, since the investigation was conducted on a reduced sample. However, it allows us to emphasize the importance of careful and well prepared studies to identify risk factors for toxoplasmosis, to adopt preventive measures and to offer guidance to at-risk populations about the disease.

Intrusion's profile in DT and PT are different. PT showed more HC than DT, however the level of intrusion and crown direction were not associated with the presence of HC.

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Background:Pyrostegia venusta (Ker. Gawl.) Miers (Bignoniacea) is a medicinal plant from the Brazilian Cerrado used to treat leucoderma and common diseases of the respiratory system.Objective:To investigate the antitumor activity of P.venusta extracts against melanoma.Materials and Methods:The cytotoxic activity and tumor induced cell death of heptane extract (HE) from P. venusta flowers was evaluated against murine melanoma B16F10-Nex2 cells in vitro and in a syngeneic model in vivo.Results:We found that HE induced apoptosis in melanoma cells by disruption of the mitochondrial membrane potential, induction of reactive oxygen species and late apoptosis evidenced by plasma membrane blebbing, cell shrinkage, chromatin condensation and DNA fragmentation, exposure of phosphatidylserine on the cell surface and activation of caspase-2,-3,-8,-9. HE was also protective against singeneyc subcutaneous melanoma HE compounds were also able to induce cell cycle arrest at G2/M phases on tumor cells. On fractionation of HE in silica gel we isolated a cytotoxic fraction that contained a mixture of saturated hydrocarbons identified by 1H NMR and GC-MS analyses. Predominant species were octacosane (C28H58-36%) and triacontane (C30H62-13%), which individually showed significant cytotoxic activity against murine melanoma B16F10-Nex2 cells in vitro and a very promising antitumor protection against subcutaneous melanoma in vivo.Conclusion:The results suggest that the components of the heptane extract, mainly octasane and triacontane, which showed antitumor properties in experimental melanoma upon regional administration, might also be therapeutic in human cancer, such as in the mostly epidermal and slowly invasive melanomas, such as acral lentiginous melanoma, as an adjuvant treatment to surgical excision.

Kielmeyera coriacea Mart. (Clusiaceae), popularly known as "pau-santo", is a typical Brazilian cerrado tree known due to its varied secondary metabolites. This study aimed to determine the allelopathic potential of the hydroalcoholic extract of leaves of K. coriacea through bioassays of seed germination, seedling growth and mitotic index of Lactuca sativa L. (lettuce). In addition it was done the tetrazolium assay and a phytochemical screening. The extract concentrations caused alterations in germination parameters, in root growth and in the mitotic index. The phytochemical screening showed the presence of triterpenes, coumarins, steroids, flavonoids and condensed tannins, compounds known to confer allelopathic characteristics upon other species. These data indicate that K. coriacea presents an allelopathic potential because its leaf extracts interfere with germination and growth without any interference of pH and osmotic potential in the results.

Neurocysticercosis, the most common parasitic disease of the central nervous system, is caused by cysticerci of the helminth Taenia solium, which is prevalent in developing countries and is reemerging in affluent societies. This helminth is associated with brain tumors and hematological malignancies in humans. In the present study, we analyzed the genotoxicity of vesicular fluid (VF) and a saline extract (SE) of T. solium metacestodes in the Drosophila melanogaster wing somatic mutation and recombination test (SMART). Third-instar larvae derived from standard and high bioactivation crosses were treated for approximately 48 hr with 12.5, 25.0, and 50.0 microg/ml of VF and SE of T. solium metacestodes. Negative (phosphate buffered saline) and positive (10 mM urethane) controls were also included. The results showed that the two test compounds were genotoxic in both crosses of Drosophila. Nevertheless, further research is needed to determine the genotoxic potential of specific compounds present in VF and SE and their role in the development of cancer.

Edited by L VerschaeveKeywords: Phytotoxic Allelopathy Allelochemicals HPLC -PAD Allium cepa DPPH Among the numerous plant species occurring in the Cerrado, Ouratea spectabilis stands out because of the lack of species that grow beneath its canopy. Therefore, this study aimed to evaluate the phytotoxic potential of different extracts and fractions of the hydroethanolic extract from leaves of O. spectabilis through laboratory bioassays of the pre-and post-emergence of seeds of Lactuca sativa L., determination of the mitotic index in root cells of Allium cepa L., antioxidant activity and phytochemical screening of different classes present in extracts and ethyl acetate fractions. It was possible to verify that different extracts and ethyl acetate fractions of O. spectabilis interfered with germination rates, as reduced germination was observed when compared with the control. Similarly, growth and development was affected in lettuce seedlings, as shown by the reduced length of primary roots and hypocotyls compared with the control. In addition, the mitotic index was reduced in treated groups compared with the negative control. HPLC-PAD analysis for both the hydroethanolic extract and its ethyl acetate fraction, showed a predominance of flavonoid compounds belonging to the groups of isoflavones and catechins in ethyl acetate fractions of hydroethanolic extracts. Thus, it was concluded that this species synthesizes phytotoxic compounds capable of interfering in the stabilization and development of other species.