Chitosan Coatings Modified with Nanostructured ZnO for the Preservation of Strawberries.

Strawberries are highly consumed around the world; however, the post-harvest shelf life is a market challenge to mitigate. It is necessary to guarantee the taste, color, and nutritional value of the fruit for a prolonged period of time. In this work, a nanocoating based on chitosan and ZnO nanoparticles for the preservation of strawberries was developed and examined. The chitosan was obtained from residual shrimp skeletons using the chemical method, and the ZnO nanoparticles were synthesized by the close-spaced sublimation method. X-ray diffraction, scanning electron microscopy, electron dispersion analysis, transmission electron microscopy, and infrared spectroscopy were used to characterize the hybrid coating. The spaghetti-like ZnO nanoparticles presented the typical wurtzite structure, which was uniformly distributed into the chitosan matrix, as observed by the elemental mapping. Measurements of color, texture, pH, titratable acidity, humidity content, and microbiological tests were performed for the strawberries coated with the Chitosan/ZnO hybrid coating, which was uniformly impregnated on the strawberries' surface. After eight days of storage, the fruit maintained a fresh appearance. The microbial load was reduced because of the synergistic effect between chitosan and ZnO nanoparticles. Global results confirm that coated strawberries are suitable for human consumption.

Development of Anxiolytic and Depression-like Behavior in Mice Infected with Mycobacterium lepraemurium.

Murine leprosy is a systemic infectious disease of mice caused by Mycobacterium lepraemurium (MLM) in which the central nervous system (CNS) is not infected; nevertheless, diseased animals show measurable cognitive alterations. For this reason, in this study, we explored the neurobehavioral changes in mice chronically infected with MLM. BALB/c mice were infected with MLM, and 120 days later, the alterations in mice were evaluated based on immunologic, histologic, endocrine, neurochemical, and behavioral traits. We found increases in the levels of IL-4 and IL-10 associated with high bacillary loads. We also found increase in the serum levels of corticosterone, epinephrine, and norepinephrine in the adrenal gland, suggesting neuroendocrine deregulation. Mice exhibited depression-like behavior in the tail suspension and forced swimming tests and anxiolytic behavior in the open field and elevated plus maze tests. The neurobehavioral alterations of mice were correlated with the histologic damage in the prefrontal cortex, ventral hippocampus, and amygdala, as well as with a blood-brain barrier disruption in the hippocampus. These results reveal an interrelated response of the neuroimmune--endocrinological axis in unresolved chronic infections that result in neurocognitive deterioration.

Study of the Thermal Annealing on Structural and Morphological Properties of High-Porosity A-WO3 Films Synthesized by HFCVD.

High-porosity nanostructured amorphous tungsten OXIDE (a-WO3) films were synthesized by a Hot Filament Chemical Vapor Deposition technique (HFCVD) and then transformed into a crystalline WO3 by simple thermal annealing. The a-WO3 films were annealed at 100, 300, and 500 °C for 10 min in an air environment. The films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), micro-Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and UV-vis spectroscopy. Results revealed that the a-WO3 films were highly porous, composed of cauliflower-like structures made of nanoparticles with average sizes of 12 nm. It was shown that the effect of annealing on the morphology of the a-WO3 films leads to a sintering process. However, the morphology is conserved. It was found that at annealing temperatures of 100 °C, the a-WO3 films are of an amorphous nature, while at 300 °C, the films crystallize in the monoclinic phase of WO3. The calculated bandgap for the a-WO3 was 3.09 eV, and 2.53 eV for the film annealed at 500 °C. Finally, the results show that porous WO3 films preserve the morphology and maintain the porosity, even after the annealing at 500 °C.

Gas1 is present in germinal niches of developing dentate gyrus and cortex.

Gas1 is a pleiotropic protein that inhibits cell growth when overexpressed in tumors but during development, it acts as a co-receptor for sonic hedgehog to promote the proliferation and survival of various growing organs and systems. This protein has been extensively studied during development in the cerebellum. However, in other structures of the central nervous system, information concerning Gas1 is limited to in situ hybridization studies. We investigate the pattern of Gas1 expression during various developmental stages of the cortex and dentate gyrus of the mouse brain. The levels of Gas1 decrease in the developing brain and the protein is mainly found in progenitor cells during the development of the cortex and dentate gyrus.

Interferon-alpha 2b quantification in inclusion bodies using reversed phase-ultra performance liquid chromatography (RP-UPLC).

Interferon-alpha 2b (IFN-alpha 2b) is a recombinant therapeutic cytokine produced as inclusion bodies using a strain of Escherichia coli as expression system. After fermentation and recovery, it is necessary to know the amount of recombinant IFN-alpha 2b, in order to determine the yield and the load for solubilization, and chromatographic protein purification steps. The present work details the validation of a new short run-time and fast sample-preparation method to quantify IFN-alpha 2b in inclusion bodies using Reversed Phase-Ultra Performance Liquid Chromatography (RP-UPLC). The developed method demonstrated an accuracy of 100.28%; the relative standard deviations for method precision, repeatability and inter-day precision tests were found to be 0.57%, 1.54% and 1.83%, respectively. Linearity of the method was assessed in the range of concentrations from 0.05 mg/mL to 0.5 mg/mL, the curve obtained had a determination coefficient (r(2)) of 0.9989. Detection and quantification limits were found to be 0.008 mg/mL and 0.025 mg/mL, respectively. The method also demonstrated robustness for changes in column temperature, and specificity against host proteins and other recombinant protein expressed in the same E. coli strain.