Adaptation and Validation of a Methodology for the Measurement of Calcium Fractions in Fruits

Calcium (Ca) content of fruit is related to fruit quality. However, total content alone is insufficient to judge fruit quality; calcium partitioning and chemical form are also important. There are multiple validated methods for determining total calcium content. However, methodologies to measure calcium fractions are not widely known and tend to be complex, affecting their accuracy. Here, based on previous work, we aim to adapt and validate a method for the extraction of the various forms of calcium in fruits. The main modification was freezing samples to minimize the loss of sample material in the procedure, reducing the centrifugation time and speed, and the addition of nitric acid (HNO₃) to improve digestion and eliminate interference from the matrix. An experiment with table grape berries cv. Thompson seedless in harvest and Postharvest (35 days) was carried out. The results of the total calcium were compared with the conventional methodology of calcination and inductively coupled plasma (ICP) measurement. We detected no and no significant differences between the two tested methods. Electron Microscope - Energy-dispersive X-ray spectroscopy analysis (SEM-EDS) and the presence of calcium oxalates were verified.     

Pea detection in food and feed samples by a real-time PCR method based on a specific legumin gene that allows diversity analysis

Real-time polymerase chain reaction is currently being used for the identification and quantification of plant and animal species as well as microorganisms in food or feed samples based on the amplification of specific sequences of low copy genes. We report here the development of a new real-time PCR method for the detection and quantification of the pea (Pisum sativum) based on the amplification of a specific region of the legS gene. The specificity was evaluated in a wide range of plant species (51 varieties of Pisum sp., and 32 other plant species and varieties taxonomically related or nonrelated). The method allows the detection and quantification of as low as 21.6 pg of DNA, which corresponds to 5 haploid genome copies. The system has been shown to be sensitive, reproducible and 100% specific for the rapid detection and quantification of pea DNA in processed food and feed samples, being therefore suitable for high-throughput analysis.     

Copper and lead adsorption as influenced by organic matter in soils from a tropical toposequence with different chemical and mineralogical attributes

The aim of this work was to investigate the influence of the organic matter on copper and lead adsorption in soils with different physiochemical and mineralogical attributes. Suspensions (pH 6.0) of a Latosol, a Neosol and a Vertisol containing increasing amounts of copper or lead were used to obtain sorption isotherms while identical experiments were carried out with the soils previously treated with H₂O₂ to remove organic matter (OM). For the undisturbed soils, L-type and H-type isotherms were predominant for copper and lead respectively, showing that lead interacts more strongly with adsorption sites. For both metals, the non-linear Freundlich adsorption model revealed higher concentration of adsorption sites for Vertisol due to 2:1 clays. For the OM-removed soils, C-type isotherms were observed for copper with the permanence of less stable and more homogeneous sites. For this metal, a high correlation (R² = 0.997) was observed between the decrease of adsorbent sites and the loss of organic carbon, evidencing the central role of organic matter on copper complexation, while lead may be able to interact efficiently with both organic matter and soil minerals.     

Efficacy of 2,6-dichlorophenol lure to control Dermacentor nitens

This study was carried out with the objective of evaluating the efficacy of a 2,6-dichlorophenol (2,6-DCP) lure to control Dermacentor nitens (Acari: Ixodidae). Slow-release formulations of the pheromone formulated with and without cypermethrin were prepared. Olfactometer bioassays were used to define the best dose of the pheromone and to evaluate the effect of cypermethrin with 2,6-DCP attractiveness. Sexually active males were released 15 cm from 2 cmx1 cm pieces of polypropylene treated with different odors: 2,6-DCP in a liposphere system (1.5, 30 and 300 microg--without cypermethrin and 30 microg--with cypermethrin) and 2,6-DCP in hexane (30 microg). The tests were conducted 7 and 15 days after the preparation of the odor sources. The percentages of males that oriented, or showed directional movement toward the stimulus, and their tracks were recorded. Lures (10 cmx2 cm pieces of polypropylene) treated with the best dose of the liposphere formulation (30 microg) were prepared. The lures were evaluated in horses that had been artificially infested with D. nitens. The horses' ears were infested with 3000 D. nitens larvae per ear, once weekly for 4 weeks. The animals were divided into three groups: control, 2,6-DCP and 2,6-DCP+cypermethrin. On day 0, the lures of their respective treatments were attached to the horses' napes. From days 6 to 20 after attachment, female ticks of 4 mm or over in length were counted on the ears, every 2 or 3 days. Olfactometer analysis showed higher orientation to 30 microg dose and more prolonged release of the pheromone in the liposphere formulation than in hexane; cypermethrin did not interfere with the attractive effect of the pheromone. The lures were efficient in the first 10 days after attachment, when the mean number of females was higher in the control group (24.9) than in 2,6-DCP and cypermethrin (5.4), and 2,6-DCP (9.2) groups. After that period the number of females was similar in the control and treated groups. These results indicate that 2,6-DCP lures used in a liposphere formulation can control D. nitens for at least 10 days by preventing its copulation. However, further evaluation of longer-term pheromone release under natural conditions is needed in order to validate this kind of control. In addition, the use of extra lures on the horse's tail may help to control populations on the hindquarters.     

Excretory-secretory products from Fasciola hepatica induce eosinophil apoptosis by a caspase-dependent mechanism

Eosinophils (Eo) are known to be important effector cells in the host defense against helminth parasites. Excretory-secretory products (ESP) released by helminths have shown wide immunomodulatory properties, such as the induction of cellular apoptosis. We investigated the ability of ESP from Fasciola hepatica to induce Eo apoptosis. In this work, we observed that ESP induced an early apoptosis of rat peritoneal eosinophils and that this phenomenon was time- and concentration-dependent. Furthermore, we demonstrated that activation of protein tyrosine kinases (TyrK) and caspases were necessary to mediate the Eo apoptosis induced by the ESP, and that carbohydrate components present in these antigens were involved in this effect. We have described for the first time the ability of ESP from F. hepatica to modify the viability of Eo by apoptosis induction. Besides that, we have observed Eo apoptosis in the liver of rats 21 days after F. hepatica infection. The diminution in Eo survival in early infection could be a parasite strategy in order to prevent a host immune response.     

Leukocyte subsets and specific antibodies in pigs vaccinated with a classical swine fever subunit (E2) vaccine and the attenuated ORF virus strain D1701

Total white blood cell (WBC) counts and percentages of CD4a+, CD8a+, CD5a+, CD45RA+, CD45RC+, wCD21+ and SWC3a+ cells in the peripheral blood of pigs were analysed in this study. Blood samples were collected before and on days 4, 10, 21 and 28 after vaccination. Group 1 pigs were vaccinated with a subunit E2 vaccine (gp E2 32 microg/dose), and Group 2 received a subunit vaccine combined with an attenuated ORF virus strain D1701 10(6.45) TCID50/dose. Control pigs received a placebo. The total WBC count and percentage of particular cell types were within the normal range in vaccinated and control pigs. Although the mechanism of attenuated ORF virus activity is not clear, changes were observed in CD4a+, CD5a+, CD8a+, CD45RA+ and CD45RC+ cells in pigs that received the combination of a subunit vaccine and ORF virus. However, the percentage of wCD21+ and SWC3a+ did not differ significantly from that recorded in pigs given only the subunit vaccine. At days 4 and 10 the number of pigs positive to E2 antibodies was higher in the group that received the subunit vaccine and ORF virus than in pigs vaccinated with the subunit vaccine only. A higher percentage of memory cells (CD45RC+) as well as Th and Tc lymphocytes in pigs that received the ORF virus and the subunit vaccine could be ascribed to a nonspecific influence of the ORF virus on the development (through cognate interactions between T and B cells) and the duration (presumed according to the finding of the clonal expression of memory cells) of humoral immunity (assessed by a higher number of seropositive pigs in this group). This seems likely since the proportion of these cells was found to be lower in the pigs that received E2 vaccine only.     

Prey Selectivity and Trophic Behavior of the Patagonian Seahorse,Hippocampus patagonicus,in Captivity

This study aims at evaluating the Patagonian seahorse, Hippocampus patagonicus, feeding behavior in captivity with regard to type and size of prey selectivity and time‐investment‐related activities for searching and capture. Experiments in aquaria were carried out under two different treatments, with and without refuge for prey. Different diets composed of amphipods (Melita palmata and Ampithoe valida), juvenile decapods (Neohelice granulata) from natural environments, and artificially cultured Artemia salina. The eaten prey’s size was analyzed and experiments with size‐controlled prey were carried out. There were neither significant differences in the prey quantity ingested between males and females nor between treatments (with or without refuge). However, significant differences were found between the quantities of each prey consumed. Amphipods and A. salina were consumed in greater quantity (P < 0.05) when compared with juvenile decapods. Experiments with A. salina of different sizes did not show significant differences on seahorses’ preference. N. granulata was highly avoided and seahorses had lower capture efficiency over this prey. Behavioral observations showed that more than 50% of the times seahorses were resting and ambushing their prey. In captivity, with optimal conditions for predation, the Patagonian seahorse modifies its opportunistic behavior, feeding selectively, and bases its food preferences on prey size and shape .     

TRANSVENOUS COIL EMBOLIZATION OF AN INTRAHEPATIC PORTOSYSTEMIC SHUNT IN A DOG

To treat an intrahepatic portosystemic shunt in a young dog, thrombogenic material was placed into the vessel lumen (transvenous coil embolization) under fluoroscopic control. One coil was placed into the shunt, followed one month later by two additional coils. Transvenous embolization may become a useful method in the treatment of some portosystemic shunts.     

Ray Liver Oils Obtained by Different Methodologies: Characterization and Refining

Currently, the use of by-products generated from fish processing is a relevant issue for the sustainable development of the fisheries. Fins are the main commercialized product of cartilaginous species. However, the livers contain a high content of polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids have been exhaustively studied due to their remarkable benefits to human health. In the present work, different methodologies were investigated to extract oil from the livers of Zearaja flavirostris and Atlantoraja castelnaui. Enzyme-assisted processes, cold extractions, and high temperatures were studied. The extraction with enzymes was the most efficient in both species. The oils obtained presented physicochemical and quality parameters suitable for its refinement and commercialization. Palmitic (C16:0) and oleic acid (C18:1) were the most abundant saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs), respectively. Both species showed similar content of DHA; however, the oil of Z. flavirostris had twice as much EPA than A. castelnaui. The results suggest that the livers of the species studied can be used as a source of valuable oils, rich in PUFAs, as a viable alternative for the integral use of these resources.