Molecular identification of Cryptosporidium spp. from fecal samples of felines, canines and bovines in the state of São Paulo, Brazil

The objective of this study was to obtain information of epidemiological nature through genotypic characterization of Cryptosporidium isolates from dogs, cats and bovines from the state of São Paulo, Brazil. The extraction of DNA from oocysts was carried out and polymerase chain reaction was accomplished using specific primers to 18S rRNA gene. The amplicons were directed sequenced. Seven cat samples, nine dog samples and nine bovine samples were analysed. From the seven cat samples the genotypic analyses revealed Cryptosporidium felis in all. These were the first genotypic characterization of Cryptosporidium from domestic felines in Brazil. In nine sequenced samples from dogs, genotypic identities compatible with Cryptosporidium canis were revealed in all samples. The genotypic analyses in bovines revealed Cryptosporidium parvum in eight samples and Cryptosporidium bovis in another sample, the last one being a non-zoonotic species, not related to clinical symptoms and described for the first time in Brazil.     

Canine leishmaniosis. Modulation of macrophage/lymphocyte interactions by L. infantum

Canine leishmaniosis, caused by Leishmania infantum, is a systemic disease with variable clinical signs and a progressive evolution. This disease is characterized by impaired T cell-mediated immune response, which has been associated with disease chronicity and high mortality. Protective immunity against leishmaniosis is thought to be mediated by T cell and cytokine production. The T cell activation requires a primary signal delivered by the major histocompatibility complex (MHC) molecules present on the surface of antigen presenting cells, and a non-specific signal generated by co-stimulatory molecules. To characterize canine immune responses in the presence of L. infantum parasites or their antigens, in vitro cell cultures of canine macrophages and lymphocytes were established, and the macrophages presenting MHC class II molecules were evaluated as well as the expression of IL-12 and CD80-86 co-stimulatory molecules and nitric oxide production. The results showed for the first time the up-regulation of MHC class II molecules on the surface in canine peripheral blood monocyte-derived macrophages during L. infantum infection in the presence of lymphocytes. In addition, a lack of co-stimulatory expression and a reduced release of nitric oxide were observed, suggesting a loss of T cell function and consequently an inactivation of the macrophage oxidative burst which, in turn, favors the survival of Leishmania. These results constitute a new contribution for the understanding of the interactions between L. infantum and the canine immune system.     

Citrus juice extraction systems: effect on chemical composition and antioxidant activity of clementine juice

Clementines are especially appreciated for their delicious flavor, and recent years have seen a great increase in the consumption of clementine juice. In previous decades, antioxidant compounds have received particular attention because of widely demonstrated beneficial health effects. In this work, the organoleptic, volatile flavor, and antioxidant quality of clementine juice were studied with regard to the influence on them by different juice extraction systems: plug inside fruit and rotating cylinders. The results showed that juice extracted by the former method presented higher yields and hesperidin content, which was related to higher antioxidant activity, demonstrated by ORAC and LDL assays. The organoleptic quality was not affected by the processing technique, whereas there were significant differences in the chemical flavor profile. There are important differences in chemical and functional quality between juice extraction techniques, which must be taken into account when employing processing systems to produce high-quality products.     

Is invasion of deforested Amazonia by the earthworm Pontoscolex corethrurus driven by soil texture and chemical properties?

Pontoscolex corethurus (Müller, 1857) is the most common invasive earthworm in disturbed lands in the tropics. Conditions required for its successful colonization of new plots are still not understood since some areas can be invaded while others, sometimes in the vicinity, are not. We kept newly hatched P. corethrurus in a wide range of Amazonian soils where population densities had been previously evaluated. We identified soil conditions that best sustain survival, soil ingestion and growth of P. corethrurus in controlled laboratory conditions and checked if presence/absence in the field was consistent with laboratory observations. While pH and Ca influenced survival; Mg and C content were the greatest determinants for growth and C:P, Mg and clay contents determined soil ingestion rates. Soil ingestion and growth rate were correlated. There were no differences in earthworm soil ingestion rates between invaded and non-invaded soils. However, growth rate and survival were higher in soils from invaded sites than in soils from non invaded sites, indicating that soil quality may play a role in the invasion process. We identified two cases where P. corethrurus did not occur: (1) unfavourable soil texture and chemical properties, but also some areas with and (2) favourable soil texture and chemical properties but no invasion. Other parameters, like vegetation cover (grass or trees), soil structure and compaction, soil hydrologic processes or biotic resistance of native earthworm communities could potentially also be key elements for understanding why P. corethrurus populations occur in some sites and not in others.     

Elemental characterization of plants and soils in Panasqueira tungsten mining region

Purpose

Mining activities represent a current source of pollution due to the large release of trace elements from mineral particles into the soil, atmosphere, and ecosystems. In active or abandoned metal-mining areas, direct discharge from mining deposits is one of the most common processes of contamination.

Materials and methods

In this work, we calculated the elemental concentrations of plants, edible for cattle, which might contain high values of toxic elements, such as As, Cu, Zn, and W, originated from mining exploitation, especially wolframite. Several species of plants originating from the same contaminated place, close to the mine, were the subject of our study in order to compare the uptake of harmful elements, from the contaminated soils, in the different plants. We have used the energy-dispersive X-ray fluorescence technique to perform the analysis and quantification of the elements present in the collected samples. The quantification was based on the fundamental parameters method for plants and on the WinAxil compare mode using a standard reference material, for soils. Calibration against a series of standard samples has been carried out.

Results and discussion

A comparison between contaminated and control samples, within the same species, was performed. The contamination of the two mining wash sites is assessed by comparing the elemental concentration of several plants in these places. Elemental content in soils was investigated, and a comparison between elemental levels in plants was performed.

Conclusions

High concentrations of tungsten were found near the new wash site. Arsenic was found throughout the area in concentrations many times higher than those recommended by the World Health Organization.     

Short-term exposure to carbaryl and UV radiation increases the reproduction output of the collembolan Folsomia candida

Purpose

Ecotoxicological risk assessment of chemical compounds is considered more accurate when mixtures of chemicals and/or interactions between chemicals and natural stressors are considered. To further simulate natural conditions, under which organisms are often exposed to combinations of natural and anthropogenic stressors, the combined exposure of a widely used insecticide, carbaryl, under UV radiation was evaluated. It is more than likely that soil organisms are confronted with a combination of chemical exposure and increasing UV irradiance on the terrestrial habitat. Considering the heterogeneity of contamination in field soils and the probability of collembolan to avoid contaminated soil (less time under exposure), combined effects of carbaryl and ultraviolet radiation were evaluated, by using a short exposure to Folsomia candida.

Materials and methods

Single exposures to carbaryl and UV radiation were performed, and adult mortality and number of laid and hatched eggs were reported. Following the results, a combined exposure was carried out, using the same conditions performed previously in the single tests. Organisms were exposed simultaneously to carbaryl (from 1 to 7 mg kg^?1) and UV doses (from 1,121.29 to 3,795.26 J m^?2), the last corresponds to 1 to 4 h of exposure. Mortality was reported, and organisms were left to lay eggs in culture boxes.

Results and discussion

Both ultraviolet radiation and high concentrations of carbaryl as single stressors increased the number of produced eggs of F. candida, with significant differences at higher concentrations (4, 5.5, and 7 mg kg^?1) of carbaryl and an EC50 of 5.93 mg kg^?1. In the case of UV radiation, statistical differences were found at all concentrations compared with control, with an EC50 of 1,248.24 J m^?2. In both cases, no significant mortality was observed. When combined, both stressors acted independently on egg production, showing additivity of effects (independent action (IA) model to data on laid eggs; SS?=?0.00056; r2?=?0.75; p?Conclusions This study highlights the importance of taking UV exposure conditions into account when assessing the impact of pesticides to soil biota and looking for more realistic scenarios while showing that soil sheltering occurs only up to a certain extent and that indirect effects can be observed. The opposite trends on responses obtained under standardized tests and short exposures to carbaryl provided some insight on the possible effects of carbaryl during collembolan life cycle.     

First report of anthracnose on Spigelia anthelmia caused by Colletotrichum karstii and Colletotrichum siamense in Brazil

Journal of Plant Diseases and Protection - In Brazil, Spigelia anthelmia is an herbaceous weedy plant normally used for the treatment of helminths in humans and animals. Leaves and stems of S....     

Whose right to (farm) the city? Race and food justice activism in post-Katrina New Orleans

Among critical responses to the perceived perils of the industrial food system, the food sovereignty movement offers a vision of radical transformation by demanding the democratic right of peoples “to define their own agriculture and food policies.” At least conceptually, the movement offers a visionary and holistic response to challenges related to human and environmental health and to social and economic well-being. What is still unclear, however, is the extent to which food sovereignty discourses and activism interact with and affect the material and social realities of the frequently low-income communities of color in which they are situated, and whether they help or hinder pre-existing efforts to alleviate hunger, overcome racism, and promote social justice. This research and corresponding paper addresses those questions by examining food justice and food sovereignty activism in the city of New Orleans since Hurricane Katrina as understood by both activists and community members. I argue, using post-Katrina New Orleans as a case study, that food projects initiated and maintained by white exogenous groups on behalf of communities of color risk exacerbating the very systems of privilege and inequality they seek to ameliorate. This paper argues for a re-positioning of food justice activism, which focuses on systemic change through power analyses and the strategic nurturing of interracial alliances directed by people residing in the communities in which projects are situated.     

Evaluation of the Antioxidant Activity of Cell Extracts from Microalgae

A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae) and 23 species of (eukaryotic) microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation) ABTS method. For complementary characterization of cell extracts, a deoxyribose assay was carried out, as well as a bacteriophage P22/Salmonella-mediated approach. The microalga Scenedesmus obliquus strain M2-1 exhibited the highest (p > 0.05) total antioxidant capacity (149 ± 47 AAU) of intracellular extracts. Its scavenger activity correlated well with its protective effects against DNA oxidative damage induced by copper(II)-ascorbic acid; and against decay in bacteriophage infection capacity induced by H₂O₂. Finally, performance of an Ames test revealed no mutagenic effects of the said extract.     

Echocardiographic evaluation including tissue Doppler imaging in New Zealand white rabbits sedated with ketamine and midazolam

Limited data are available on the use of more recent echocardiographic parameters in the rabbit. Echocardiographic examination, including conventional echocardiography and tissue Doppler imaging (TDI), was performed on 26 male New Zealand white rabbits under ketamine–midazolam sedation. Particular emphasis was placed on the more recent systolic and diastolic parameters, such as myocardial performance index (Tei index) and mitral annular motion (from septal and lateral sides of the left ventricle) obtained using pulsed TDI.Parameters that assessed systolic and diastolic function (fractional shortening, Tei index, and maximal mitral E- and A-wave velocities) were comparable to those reported in the literature for rabbits in the awake state. The less cardiodepressive anaesthetic protocol could offer a good alternative in performing echocardiographic evaluation whenever such caution is necessary. TDI is feasible in healthy rabbits and potentially suitable for the investigation of left ventricle systolic and diastolic function.