Modification of Oxalis tuberosa starch with OSA, characterization and application in food-grade Pickering emulsions

The emulsifying properties of Oxalis tuberosa starch (native and chemically modified) were evaluated in Pickering emulsions based on the emulsification index, emulsion stability over time and emulsion morphology. The best conditions of chemical modification were found by esterification of starch with octenyl succinic anhydride (OSA) at a concentration of 3% and a reaction time of 2 h, achieving a degree of substitution of 0.033 ± 0.001. The results obtained using Fourier-transform infrared spectroscopy, a Rapid Visco Analyzer, and differential scanning calorimetry, indicated that the starch underwent a change in its structure and that the insertion of the OSA groups was achieved. The amphipathic characteristics of OSA starch were evaluated by forming oil-in-water emulsions. Various concentrations of OSA-starch granules (1, 2.5 and 5 wt%) were used. A higher concentration of particles produced a smaller droplet size of emulsions (76.5 ± 0.9 μm) compared to those formed at a lower concentration of 1% (92.5 ± 1.0 μm). Therefore, the starch modified with OSA displayed the necessary characteristics to be adsorbed at the oil-water interface, achieving Pickering emulsion stabilization.

[Granulocyte colony-stimulating factor in the treatment of febrile neutropenia]

PURPOSE

To determine whether granulocyte colony-stimulating factor (G-CSF) used in addition to antibiotic therapy, in patients with chemotherapy-induced febrile neutropenia shortens the period of fever, neutropenia and hospitalization.

PATIENTS AND METHODS

The study was prospective. Patients with lymphoblastic acute leukemia (LAL) were included. They received intensive chemotherapy of induction, intensification, or consolidation. At random, a group received amikacin-ceftriaxone; if no had response after 3 days, we added vancomicin and, after 7 days, amphotericin. The other group received in addition these antibiotics, granulocyte colony-stimulating factor.

RESULTS

The groups were comparable in the magnitude of the initial neutropenia (< 0.5 x 10(9)/L), site of the infection, chemotherapy received germs isolated, age, and sex. The patients of the group that received FEC-G were cured in the course of 3.1 days; in the group without FEC-G, this occurred in 7.2 days (p = 0.0001). At the end of the infectious episode, the number of neutrophils, in the group with FEC-G, was of 1.9 x 10(9)/L versus 0.7 x 10(9)/L (p = 0.0009). The mortality was of one and two cases (p = 0.46). The global mortality was 7.5%.

CONCLUSIONS

The addition of FEC-G to the treatment with antibiotics, in febrile neutropenia, decreases duration of days with fever, hospitalization and neutropenia. However, the frequency of cure is not augmented.