Prevalence of Bartonella species DNA and antibodies in cats (Felis catus) submitted to a spay/neuter program in Rio de Janeiro, Brazil

The prevalence of Bartonella species DNA and antibodies for Bartonella henselae were studied in 40 clinically healthy cats (Felis catus, Linnaeus 1758) submitted to a spay/neuter program in Rio de Janeiro, Brazil. Additionally, the prevalence of Bartonella species DNA was investigated in the fleas found parasitizing the subject cats. For this purpose, blood samples were obtained from all cats, and DNA extraction was performed on the blood, and blood clotted samples, as well as on pools of fleas obtained from them. Antibodies for B henselae were detected on serum samples. Bartonella species DNA was detected in 17 cats, whereas serum reactivity for B henselae was found in 19. A total of 20 cats were flea-infested and nine of these 20 had Bartonella species DNA in their blood. In four of the 20 flea-infested cats, Bartonella species DNA was detected in the fleas obtained from those cats, but only one of these four cats had Bartonella species DNA in its blood.     

Low dose γ-irradiation as a suitable solution for chestnut (Castanea sativa Miller) conservation: effects on sugars, fatty acids, and tocopherols

Along with dehydration, the development of insects and microorganisms is the major drawback in chestnut conservation. Irradiation has been regaining interest as an alternative technology to increase food product shelf life. In the present work, the effects of low dose gamma irradiation on the sugar, fatty acid, and tocopherol composition of chestnuts stored at 4 °C for different storage periods (0, 30, and 60 days) was evaluated. The irradiations were performed in a 60Co experimental equipment, for 1 h (0.27±0.04 kGy) and 2 h (0.54±0.04 kGy). Changes in sugars and tocopherols were determined by high performance liquid chromatography coupled to refraction index and fluorescence detections, respectively, while changes in fatty acids were analyzed by gas-chromatography coupled to flame ionization detection. Regarding sugar composition, storage time proved to have a higher effect than irradiation treatment. Fructose and glucose increased after storage, with the corresponding decrease of sucrose. Otherwise, the tocopherol content was lower in nonirradiated samples, without a significant influence of storage. Saturated, monounsaturated, and polyunsaturated fatty acids levels were not affected, either by storage or irradiation. Nevertheless, some individual fatty acid concentrations were influenced by one of two factors, such as the increase of palmitic acid in irradiated samples or the decrease of oleic acid after 60 days of storage. Overall, the assayed irradiation doses seem to be a promising alternative treatment to increase chestnut shelf life, without affecting the profile and composition in important nutrients.     

Anti-Hepatocellular Carcinoma (HepG2) Activities of Monoterpene Hydroxy Lactones Isolated from the Marine Microalga Tisochrysis Lutea

Tisochrysis lutea is a marine haptophyte rich in omega-3 polyunsaturated fatty acids (e.g., docosahexaenoic acid (DHA)) and carotenoids (e.g., fucoxanthin). Because of the nutraceutical applications of these compounds, this microalga is being used in aquaculture to feed oyster and shrimp larvae. In our earlier report, T. lutea organic crude extracts exhibited in vitro cytotoxic activity against human hepatocarcinoma (HepG2) cells. However, so far, the compound(s) accountable for the observed bioactivity have not been identified. Therefore, the aim of this study was to isolate and identify the chemical component(s) responsible for the bioactivity observed. Bioassay-guided fractionation through a combination of silica-gel column chromatography, followed by preparative thin layer chromatography (PTLC), led to the isolation of two diastereomers of a monoterpenoid lactone, namely, loliolide (1) and epi-loliolide (2), isolated for the first time in this species. The structural elucidation of both compounds was carried out by GC-MS and 1D (¹H and ¹³C APT) and 2D (COSY, HMBC, HSQC-ed, and NOESY) NMR analysis. Both compounds significantly reduced the viability of HepG2 cells and were considerably less toxic towards a non-tumoral murine stromal (S17) cell line, although epi-loliolide was found to be more active than loliolide.     

The main proteinases in Dermatobia hominis second and third instars larvae are serine-proteinases

We performed a combination of proteinase assay, either in solution or immobilized in sodium dodecyl sulfate-polyacrylamide gel copolymerized with gelatin, to detect and quantify proteinases of Dermatobia hominis second (L2) and third (L3) instar larvae. In the quantitative assay, we examined proteinase activity by hydrolysis of a panel of peptide bonds specific for the main proteinase classes. We verified that the pGlu-Phe-Leu p-nitroanilide substrate was hydrolyzed by crude extracts of L2 (3.0+/-0.2 nmol h(-1)mg of protein(-1)) and L3 (7.7+/-0.1 nmol h(-1)mg of protein(-1)) and that both activities were partially inhibited by trans-epoxysuccinyl-l-leucylamido-(4-guanidino)butane, 15% and 3%, respectively. Also, we demonstrated that the Nalpha-p-Tosyl-l-Arg methyl ester substrate was hydrolyzed by crude extracts of L2 (117+/-24 nmol h(-1)mg of protein(-1)) and L3 (111+/-10 nmol h(-1)mg of protein(-1)), suggesting a predominance of esterase activity in the crude larval preparation. Interestingly, the specific activity of serine-proteinases was totally inhibited by phenylmethylsulphonyl fluoride in the L3 crude extract, while only 10% of this enzyme class activity was inhibited in the L2 crude extract. The results of the qualitative assays with substrate gels suggested that L2 and L3 larvae express serine-proteinases with similar (13 and 22 kDa) and distinct (50 kDa in L2 and 30 kDa in L3) relative molecular masses. These findings contribute to the biochemical characterization of D. hominis L2 and L3 larvae.     

Initial growth and survival of Eucalyptus spp. and Mimosa caesalpiniifolia Benth. in silvopastoral systems and their impact on herbage accumulation of Urochloa decumbens Stapf R. D. Webster

Agroforestry Systems - Silvopastoral systems (SPS) combine tree, herbaceous, and animal components, and may contribute to improve productivity and diversification of activities over time. This...     

Bursatella leachii from Mar Menor as a Source of Bioactive Molecules: Preliminary Evaluation of the Nutritional Profile,In Vitro Biological Activities,and Fatty Acids Contents

Marine invertebrates contain nutritionally important elements that make them suitable to be included in the human diet, and they are considered an outstanding source of secondary metabolites with multiple biotechnological uses. The sea hare Bursatella leachii is an invasive species in Mar Menor that can be managed through the control of its reproduction and/or by massive biomass removal. In this context, this work evaluated the possible use of biomass from B. leachii in the food and cosmetics industries. Biomass was appraised for nutritional properties, and extracts were prepared and evaluated in vitro for antioxidant and anti-inflammatory capacity, cholinesterase and tyrosinase inhibition, and for total contents in different phenolic groups. It had a moderate moisture level, low ash and fat levels, and an adequate protein amount and protein/lipid ratio. The fatty acids (FA) profile was mainly saturated, dominated by palmitic acid. The methanol extract had the highest acetylcholinesterase inhibition. The acetone extract had the strongest capacity to scavenge 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical, reduce iron, inhibit tyrosinase, decrease nitric oxide production in lipopolysaccharide (LPS)-stimulated microglia cells, and the upmost levels of total phenolics, flavonoids, and tannins. Our results suggest multiple biotechnological applications for B. leachii biomass in different economic areas.