Porifera Lectins: Diversity,Physiological Roles and Biotechnological Potential

An overview on the diversity of 39 lectins from the phylum Porifera is presented, including 38 lectins, which were identified from the class of demosponges, and one lectin from the class of hexactinellida. Their purification from crude extracts was mainly performed by using affinity chromatography and gel filtration techniques. Other protocols were also developed in order to collect and study sponge lectins, including screening of sponge genomes and expression in heterologous bacterial systems. The characterization of the lectins was performed by Edman degradation or mass spectrometry. Regarding their physiological roles, sponge lectins showed to be involved in morphogenesis and cell interaction, biomineralization and spiculogenesis, as well as host defense mechanisms and potentially in the association between the sponge and its microorganisms. In addition, these lectins exhibited a broad range of bioactivities, including modulation of inflammatory response, antimicrobial and cytotoxic activities, as well as anticancer and neuromodulatory activity. In view of their potential pharmacological applications, sponge lectins constitute promising molecules of biotechnological interest.     

Primary cutaneous undifferentiated round cell tumor with concurrent polymyositis in a dog

A cutaneous poorly differentiated round cell tumor with concurrent, non-suppurative, polymyositis was diagnosed in a hovawart dog. Histochemical staining, immunohistochemistry, and transmission electron microscopy findings suggested that the tumors cells were of myeloid, or possibly natural killer cell origin. The possibility that the concurrent polymyositis may represent a pre-neoplastic or paraneoplastic process is discussed.     

HEV infection in swine from Eastern Brazilian Amazon: evidence of co-infection by different subtypes

Hepatitis E virus (HEV) is a fecal-orally transmitted member of the genus Hepevirus that causes acute hepatitis in humans and is widely distributed throughout the world. Pigs have been reported as the main source of genotypes 3 and 4 infection to humans in non-endemic areas. To investigate HEV infection in pigs from different regions of Pará state (Eastern Brazilian Amazon), we performed serological and molecular analyses of serum, fecal and liver samples from 151 adult pigs slaughtered between April and October 2010 in slaughterhouses in the metropolitan region of Belém, Pará. Among the animals tested, 8.6% (13/151) were positive for anti-HEV IgG but not for anti-HEV IgM. HEV RNA was detected in 4.8% (22/453) of the samples analyzed and 9.9% (15/151) of the animals had at least one positive sample. Phylogenetic analysis showed that all sequences belonged to genotype 3 that were related to human isolates from other non-endemic regions, suggesting that the isolates had zoonotic potential. Subtypes 3c and 3f were simultaneously detected in some pigs, suggesting co-infection by more than one strain and/or the presence of a recombinant virus. These results constitute the first molecular and serologic evidence of swine HEV circulation in the Eastern Brazilian Amazon.     

Can roads be used as transects for primate population surveys?

Line transect distance sampling (LTDS) can be applied to either trails or roads. However, it is likely that sampling along roads might result in biased density estimates. In this paper, we compared the results obtained with LTDS applied on trails and roads for two primate species (Callithrix penicillata and Callicebus nigrifrons) to clarify whether roads are appropriate transects to estimate densities. We performed standard LTDS surveys in two nature reserves in south-eastern Brazil. Effective strip width and population density were different between trails and roads for C. penicillata, but not for C. nigrifrons. The results suggest that roads are not appropriate for use as transects in primate surveys, at least for some species. Further work is required to fully understand this issue, but in the meantime we recommend that researchers avoid using roads as transects or treat roads and trails as covariates when sampling on roads is unavoidable.     

Physiological and biochemical responses of <Emphasis Type="Italic">Dolichos lablab</Emphasis> L. to cadmium support its potential as a cadmium phytoremediator

Purpose

This study aims to investigate the response of a high biomass producer non-hyperaccumulator legume plant species, Dolichos lablab L., to cadmium (Cd) stress for phytoremediation process.

Materials and methods

Three individual experiments were carried out to assess physiological and biochemical parameters to support the use of this plant species as a phytoremediator. The first experiment was carried out in Cd-contaminated soil while the second and third experiments were conducted in sand in which Cd was applied to study biochemical responses. Analysis of mineral nutrition, phytoremediation parameters, antioxidant response, and protein identification by gel-based proteomics were performed.

Results and discussion

Good tolerance to Cd under moderate level of contamination was observed. Mineral nutrition was little affected, and phytoremediation index was satisfactory. Additionally, biochemical responses based on antioxidant enzyme analysis were well responsive in roots, reflecting the capacity of Cd stress attenuation in this organ. A proteomic analysis revealed positive regulation of root proteins involved in carbohydrate, amino acids, nitrogen metabolism, and abiotic/biotic stress response, which together may contribute to create a scenario to overcome Cd-induced stress.

Conclusions

Based on the physiological and biochemical results, we concluded that D. lablab L. is suitable for phytoremediation/phytostabilization purposes.

     

Low Concentrations of Glyphosate-Based Herbicide Affects the Development of <Emphasis Type="Italic">Chironomus xanthus</Emphasis>

Glyphosate is an herbicide commonly used worldwide for weed control and generally applied as part of a formulated product, such as Roundup. Contamination of surface water by glyphosate-based herbicides can cause deleterious effects in organisms, mainly in aquatic systems near to intensive agricultural areas (e.g., transgenic soybean crops). Given the lack of toxicological information concerning effects of glyphosate-based herbicides on tropical aquatic ecosystems, we aimed to evaluate the lethal and sub-lethal effects of Roundup Original® on the dipteran Chironomus xanthus. The endpoints evaluated included survival, growth, and emergence. The results showed that the 48 h LC₅₀ for glyphosate to C. xanthus was 251.5 mg a.e./L. Larval growth of C. xanthus was reduced under glyphosate exposure (LOEC for body length = 12.06 mg/L; LOEC for head capsule width = 0.49 mg/L). No effects were observed in terms of cumulative percentage of imagoes emergence. However, low concentrations of glyphosate caused delayed emergence of females (at 1.53 mg/L) and induced fast emergence of males (at 0.49 mg/L), compared to control treatment. The deleterious effects of environmental relevant concentrations of glyphosate (0.7 mg/L) observed in terms of C. xanthus growth and development suggest that glyphosate-based herbicides can have negative consequences for aquatic non-target invertebrates such as Chironomus. Multigerational assays are needed to assess the long term effects of glyphosate on C. xanthus populations. Finally, our study adds ecotoxicological data on the effects of glyphosate-based herbicides on tropical freshwater invertebrates.     

NDVI variation according to the time of measurement,sampling size,positioning of sensor and water regime in different soybean cultivars

Although the information on the Normalized Difference Vegetation Index (NDVI) in plants under water deficit is often obtained from sensors attached to satellites, the increasing data acquisition with portable sensors has wide applicability in agricultural production because it is a fast, nondestructive method, and is less prone to interference problems. Thus, we carried out a set of experiments to investigate the influence of time, spatial plant arrangements, sampling size, height of the sensor and water regimes on NDVI readings in different soybean cultivars in greenhouse and field trials during the crop seasons 2011/12, 2012/13 and 2013/14. In experiments where plants were always evaluated under well-watered conditions, we observed that 9 a.m. was the most suitable time for NDVI readings regardless of the soybean cultivar, spatial arrangement or environment. Furthermore, there was no difference among NDVI readings in relation to the sampling size, regardless of the date or cultivar. We also observed that NDVI tended to decrease according to the higher height of the sensor in relation to the canopy top, with higher values tending to be at 0.8 m, but with no significant difference relative to 1.0 m—the height we adopted in our experiments. When different water regimes were induced under field conditions, NDVI readings measured at 9 a.m. by using a portable sensor were successful to differentiate soybean cultivars with contrasting responses to drought.