Sphingosines Derived from Marine Sponge as Potential Multi-Target Drug Related to Disorders in Cancer Development

Haliclona tubifera, marine sponge species abundant in Brazilian coastline, presents only a few papers published in the literature. Recently, we have reported the isolation of two modified C18 sphingoid bases: (2R,3R,6R,7Z)-2-aminooctadec-7-ene-1,3,6-triol and and (2R,3R,6R)-2-aminooctadec-1,3,6-triol. In order to continue our research, in this work aimed at the biological investigation of fractions that led to the isolation of these compounds. We evaluated the cytotoxic effect of marine sponge H. tubifera fractions in glioma (U87) and neuroblastoma (SH-SY5Y) human cell lines. In addition, considering the link between cancer, imbalance of reactive oxygen species and coagulation disorders, we also investigated the in vitro effects on blood coagulation and their redox properties. We showed that the ethyl acetate (EtOAc) fraction, rich in sphingoid bases, had important cytotoxic effects in both cancer cell lines with an IC₅₀ < 15 μg/mL and also can inhibit the production of peroxyl radicals. Interestingly, this fraction increased the recalcification time of human blood, showing anticoagulant properties. The present study indicates the sphingosines fraction as a promising source of chemical prototypes, especially multifunctional drugs in cancer therapy.     

Maintaining post‐grazing sward height of Panicum maximum (cv. Mombaça) at 50 cm led to higher animal performance compared with post‐grazing height of 30 cm

In swards of tall, tufted, tropical grasses like Mombaça guinea grass (Panicum maximum (Jacq.)), post‐grazing heights promote changes in sward structure, which influence animal performance. This study evaluated changes in sward structure in response to grazing management at two post‐grazing heights (30 and 50 cm), associated with 90 cm pre‐grazing height. Each treatment was allocated to experimental unit (1.5 ha) in three replicated blocks. Pastures were evaluated pre‐ and post‐grazing to estimate herbage mass, percentages of leaf (LP), stem (SP) and dead material (DP), and nutritive value (VN). Stocking rate was adjusted twice a week “using the put‐and‐take approach,” and animals were weighed every 28 days. Forage accumulation rate was greater for pasture managed at 30 cm (64.8 vs. 55.1 kg ha^?1 day^?1) than 50 cm. A greater number of days were required after grazing 30‐cm residual pasture to achieve the pre‐grazing target height, resulting in 25% decrease in number of grazing cycles compared with pastures managed at 50 cm. Regardless of post‐grazing height targets, SP and DP decreased, whereas LP and NV increased from soil level to top of canopy. Stocking rate was greater in pastures managed to 30 cm than in those managed to 50 cm residual height (4.7 vs. 3.4 AU ha^?1). However, average daily gain was greater for 50 cm than for 30 cm post‐grazing height (795 vs. 590 g steer^?1 day^?1), resulting in a greater animal production per area (917 vs. 794 kg/ha of live weight). Thus, Mombaça guinea grass subject to intermittent grazing should be managed at 50 cm residual height.     

Soil compaction caused by harvesting,skidding and wood processing in eucalyptus forests on coarse‐textured tropical soils

Eucalyptus forests play a major role in the world economy, providing raw materials for different purposes. In planted forests, harvest operations performed by heavy machinery may cause severe soil compaction. This study aimed to evaluate the impact of a full‐tree harvesting system in planted eucalyptus forests from Northeastern Brazil. Different soils were evaluated (two Hapludults and one Haplorthod) in two horizons (BA and Bt). We tested different equipment, namely feller buncher, skidder (with traffic intensities of 3, 6, 12 and 16 passes), flail (at different ground‐contact points), grapple saw and loader. The soil physical attributes reflected not only the impact of equipment traffic but also the intrinsic differences between the soils. Bulk density (ranging from 1.36 to 1.80 t m^?3 after trafficking) related well to soil class and horizon. Precompression stress (ranging from 203 to 430 kPa) and degree of compaction (76%–94%) following trafficking were well correlated, while increase in bulk density (reaching a maximum of 20%) related more strongly to soil moisture. A contingency table was constructed with the number of compacted samples and further examined by correspondence analysis. Compaction varied according to soil, horizon and equipment, indicating that machine–soil interactions are very specific and demand detailed research under different conditions. The Haplorthod experienced the greatest amount of compaction, whereas the Hapludult‐2 was more resistant (60% and 25% of compacted samples, respectively). The grapple saw and the skidder at higher traffic intensities (12 and 16 passes) exerted the highest mechanical impacts (81% and 67% of compacted samples, respectively).     

Effect of melatonin on DNA damage of bovine cumulus cells during in vitro maturation (IVM) and on in vitro embryo development

The effect of melatonin during in vitro maturation (IVM) on DNA damage of cumulus cells (CCs) from bovine cumulus-oocyte complexes (COCs) and embryo development was evaluated. COCs from abattoir ovaries were cultured in maturation medium (MM) with 0.5μg/ml FSH and 5.0μg/ml LH (FSH-LH); 10(-9)M melatonin (MEL) or FSH-LH+MEL (FSH-LH-MEL). After 24h of in vitro maturation, the CCs surrounding the oocyte were subjected to DNA analysis by Comet assay. After in vitro fertilization and in vitro embryo culture, the embryo development rates were evaluated on day 2 post insemination (cleavage) and days 7-8 (blastocyst). The percentage of CCs with no DNA damage was significantly superior in MEL group (37.6±2.4) than in FSH-LH-MEL (28.0±2.4) and FSH-LH (17.8±2.41) groups. Cleavage and blastocysts rates were similar among groups. Melatonin during IVM protects the CCs from DNA damage but this effect did not influence embryo development in vitro.     

Intake and ingestive behavior of lambs fed diets containing ammoniated buffel grass hay

This study aimed to evaluate the effect of diets with ammoniated buffel grass hay on the ingestive behavior of feedlot lambs. Thirty-two sheep of no defined breed with an average body weight of 17.7?±?1.8 kg were used. A completely randomized design with four treatments (0, 18, 36, and 54 g/kg dry matter (DM) basis) and eight repetitions was used. Ingestive behavior, rumination, and idle time were similar (P?>?0.05) among the diets containing ammoniated buffel grass hay, with mean values of 294.5, 554.44, and 594.25 min per day, respectively. Regarding the chews, all of the variables resulted in similar behavior (P?>?0.05). The quadratic effect (P?<?0.05) observed for daily intake can be explained based on the amount of DM and neutral detergent fiber (NDF) per meal per rumination. There was no effect of urea levels from the ammoniation (P?>?0.05) on the efficiency of DM and NDF consumption. However, the rumination efficiency of DM and NDF showed a quadratic effect (P?<?0.05). Thus, the use of ammoniated buffel grass hay with urea in lamb diet affects the ingestive behavior by increasing the rumination efficiency, increased intake, and feed utilization.