Evaluation of proanthocyanidin-crosslinked sericin/alginate blend for ketoprofen extended release

Sericin and alginate blend has shown good results for obtaining sustained release dosage forms. In the case of ketoprofen, it was necessary to resort to the use of the proanthocyanidin (PA) as crosslinking agent in order to achieve this same goal. Thus, various formulations were developed by adding different initial amounts of PA to the sericin and alginate blend with incorporated ketoprofen. The best results for drug loading, entrapment efficiency and release prolongation were obtained for the particle with the lowest amount of PA (0.5%). Mathematical modeling has indicated that different mechanisms may be involved in drug release, especially a complex release mechanism, with polymer dissolution and polymer chain relaxation allowing drug release. Particles characterization confirmed the incorporation of ketoprofen into the sericin, alginate and proanthocyanidin blend. It was verified that there was no interaction between them and there were no major changes in the physicochemical properties of the drug.     

Nutritional composition,fatty acid profile,phytochemistry and evaluation of the effects of Carya illinoinensis on diabetes

The increase in chronic diseases has arisen interest to search for alternative treatments so that people can improve their quality of life. Thus, Carya illinoinensis is the subject of the present work which aims at determining whether it has antidiabetic activity. The plant was collected and its nuts were separated from their peels, dried and grinded and incorporated into the feed, in concentration of 6% and 10%, for the treatment of animals. The centesimal composition of this diet was also determined. From the nut was also obtained the fixed oil, for the profile of fatty acids, and the 70% hydroethanolic extract for the phytochemical analysis. The results have shown that species presents hypoglycaemic effect, high fat composition of unsaturated fatty acids and the presence of some phenolic compounds, directly related to the antidiabetic activity. Therefore, the specie presente benefits that can contribute to the binomial diet/health.     

Biocompatibility studies of natural rubber latex from different tree clones and collection methods

Natural rubber latex (NRL) has several features that make it an excellent biomaterial to promote the growth and repair of tissues, skin and bones. Most of the research with NRL membranes uses a mixture of different clones and chemical preservatives in the collection process. In this study, we compared five clones that produce NRL, seeking to identify their differences in biocompatibility. The clones studied were RRIM 600, PB 235, GT1, PR 255 and IAN 873 commonly found in plantations in Brazil. We did also study the effect of ammonia used during latex collection. NRL membranes were prepared aseptically and sterilized. In the in vitro tests, the membranes remained in direct contact with mouse fibroblasts cells for three periods, 24, 48 and 72 h. In the in vivo tests, the membranes were implanted subcutaneously in rabbits. The results indicated the biocompatibility of the membranes obtained from all clones. Membranes from the clones RRIM 600 and IAN 873 induced greater cell proliferation, suggesting greater bioactivity. It was found that the membranes made from latex that was in contact with ammonia during collection, showed cytotoxic and genotoxic effects in cultures, as well as necrosis, and increased inflammatory cells in the rabbit’s tissues close to the implant.     

The economic cost of metritis in dairy herds

The objective of this study was to estimate the cost of metritis in dairy herds. Data from 11,733 dairy cows from 16 different farms located in 4 different regions of the United States were compiled for up to 305 d in milk, and 11,581 cows (2,907 with and 8,674 without metritis) were used for this study. Metritis was defined as fetid, watery, red-brownish vaginal discharge that occurs ≤21 d in milk. Continuous outcomes such as 305-d milk production, milk sales ($/cow), cow sales ($/cow), metritis treatment costs ($/cow), replacement costs ($/cow), reproduction costs ($/cow), feeding costs ($/cow), and gross profit per cow ($/cow) were analyzed using mixed effect models using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). Gross profit was also compared using the Kruskal–Wallis test. Dichotomous outcomes such as pregnant and culling by 305 d in milk were analyzed using the GLIMMIX procedure of SAS. Time to pregnancy and culling were analyzed using the PHREG procedure of SAS. Models included the fixed effects of metritis, parity, and the interaction between metritis and parity, and farm as the random effect. Variables were considered significant when P ≤ 0.05. Metritis cost was calculated by subtracting the gross profit of cows with metritis from the gross profit of cows without metritis. A stochastic analysis was performed with 10,000 iterations using the observed results from each group. Milk yield and proportion of cows pregnant were lesser for cows with metritis than for cows without metritis, whereas the proportion of cows leaving the herd was greater for cows with metritis than for cows without metritis. Milk sales, feeding costs, residual cow value, and gross profit were lesser for cows with metritis than for cows without metritis. Cow sales and replacement costs were greater for cows with metritis than for cows without metritis. The mean cost of metritis from the study herds was $511 and the median was $398. The stochastic analysis showed that the mean cost of a case of metritis was $513, with 95% of the scenarios ranging from $240 to $884, and that milk price, treatment cost, replacement cost, and feed cost explained 59%, 19%, 12%, and 7%, respectively, of the total variation in cash flow differences. In conclusion, metritis caused large economic losses to dairy herds by decreasing milk production, reproduction, and survival in the herd.     

Maximum suction lift of water jet pumps

This paper describes an experimental study on water jet pumps with different diameters and nozzle-to-throat area ratios. The results revealed that the area ratio was an important parameter to characterize the maximum suction lift of the jet pumps, while their diameters had a negligible effect. All jet pumps reached the cavitation regime at a suction lift of about 8 mH₂O. In the non-cavitating region, it was found that the higher the area ratio, the higher the maximum suction lift for the same motive pressure head. However, the lower the area ratio, the higher the resistance to enter the cavitation regime. A dimensionless correlation was obtained for the non-cavitating region to describe the maximum suction lift as a function of a modified Thoma number and the area ratio. Curve fitting of experimental data also provided a dimensionless correlation to predict the onset of cavitation. Finally, applications of the results are presented.     

Redox-active electrolyte for carbon nanotube-based electric double layer capacitors

The specific capacitance of the MWCNTs was improved by the addition of an electrochemically active compound (indigo carmine) to an electrolyte generally used in electric double layer capacitors. The pseudocapacitive contribution of the IC trebled the specific capacitance values of the MWCNTs at low current densities (from 17 Fg⁻¹ to 50 Fg⁻¹). The good resistance obtained for the MWCNT-based capacitor was not modified with the use of this novel redox-active electrolyte. A reversible process associated to the redox reaction of IC was found to be responsible for the capacitance increase observed. Therefore, a combined effect of double layer formation and pseudocapacitive phenomena is presented. Long-term cycling experiments performed showed good stability with a reduction of the initial capacitance values of 30% after 10,000 galvanostatic cycles at 360 mAg⁻¹. The efficiency of the cell was close to 100% throughout the experiment.