Medicinal species with gastroprotective activity found in the Brazilian Cerrado

Peptic and/or duodenal ulcers are characterized by diverse acute and chronic ulcerative lesions that commonly arise in any portion of the gastric mucosa that is exposed to the aggressive action of gastric acid. The pathophysiology of peptic ulcers has been attributed to an imbalance between aggressive and protective factors. In Brazil, medicinal plants are commonly used to treat this ailment. A country with great biodiversity, Brazil is considered a rich source of therapeutic products. There have been popular and pharmacological reports on the medicinal relevance of the Brazilian cerrado plant species, including Ananas ananassoides, Celtis iguanaea, Encholirium spectabile, Hymenaea stigonocarpa, Lafoensia pacari, Qualea grandiflora, Qualea parvifora, Mouriri pusa, Solanum lycocarpum, Solanum paniculatum, Serjania erecta, and Vochysia tucanorum, in the treatment of stomach disorders. The aim of the present review was to report on some of the Brazilian cerrado plants that are used in folk medicine because of their gastroprotective potential and to encourage novel studies in the search and preservation of plants with this therapeutic potential.     

Ultrasound-Assist Extrusion Methods for the Fabrication of Polymer Nanocomposites Based on Polypropylene/Multi-Wall Carbon Nanotubes

Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 10¹³ to 10⁵ Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods.     

Evaluation of environmental genotoxicity by comet assay in Columba livia

The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as “sentinels,” as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection–fluorescence in situ hybridization (DBD–FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD–FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants.