Use of the jabuticaba (Myrciaria cauliflora) depulping residue to produce a natural pigment powder with functional properties

The aim of this study was to produce a natural pigment powder with functional properties. To optimise the spray-drying process, a central composite design with 17 treatments was used, in which the independent variables were the inlet drying air temperature (138–202 °C), the feed flow rate (20–67 mL/min), and the concentration of the carrier (maltodextrin, 100–300 g/kg of extract). The dependent variables were the moisture content, hygroscopicity, and anthocyanin retention. The samples were analysed by: anthocyanin and phenolic content; antioxidant properties based on the ORAC and DPPH assays; antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Salmonella enteritidis, and Escherichia coli; and inhibitory activity against arginase, an enzyme produced by Leishmania amazonensis. The experimental design was not significant or predictive in the ranges studied. The selected samples contained high concentrations of anthocyanins and phenolics, and high antioxidant capacities. In addition, they exhibited antimicrobial activity against three of the four microorganisms tested, and some of the samples also exhibited a bactericidal effect. Moreover, the powders exerted inhibitory activity (64–69%) against arginase. The results obtained in this study suggest that the jabuticaba depulping residue could be used to produce a natural pigment with functional properties.     

HeLa cell transfection using a novel sonoporation system

Sonoporation has been shown to have an important role in biotechnology for gene therapy and drug delivery. This paper presents a novel microfluidic sonoporation system that achieves high rates of cell transfection and cell viability by operating the sonoporation chamber at resonance. The paper presents a theoretical analysis of the resonant sonoporation chamber design, which achieves sonoporation by forming an ultrasonic standing wave across the chamber. A piezoelectric transducer (PZT 26) is used to generate the ultrasound and the different material thicknesses have been identified to give a chamber resonance at 980 kHz. The efficiency of the sonoporation system was determined experimentally under a range of sonoporation conditions and different exposures time (5, 10, 15, and 20 s, respectively) using HeLa cells and plasmid (peGFP-N1). The experimental results achieve a cell transfection efficiency of 68.9% (analysis of variance, ANOVA, p < 0.05) at the resonant frequency of 980 kHz at 100 V(p-p) (19.5 MPa) with a cell viability of 77% after 10 s of insonication.     

Physical Properties of Gelatin Films Plasticized by Blends of Glycerol and Sorbitol

ABSTRACT: The addition of plasticizers increases the flexibility and workability of films based on biopolymers. However, the use of some plasticizers cause undesirable results, such as the migration of these additives out the film or crystallization during shelf life. Thus, the aim of this study was to evaluate the effect of blends with different ratios of sorbitol and glycerol, at 2 plasticizer concentrations, on mechanical, viscoelastic, and water vapor barrier properties of films based on gelatin. The films were prepared with 2 g gelatin/100 mL of water and with 25 or 55 g plasticizer/100 g gelatin. The ratio, glycerol to sorbitol, was studied as 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0. The increase of plasticizer concentration from 25 to 55 g plasticizer/100 g gelatin caused an increase of flexibility and reduction of resistance and water vapor barrier as expected. In relation to the effect of the mixture, the increase in the proportion of glycerol caused a reduction of the puncture force, tensile strength, modulus of elasticity, and an increase of the puncture deformation, elongation at break, and water vapor permeability due to the higher plasticizing effect of glycerol. This behavior was explained in terms of molecular weight of the plasticizers, which demonstrated that the studied properties could be considered as functions of the number of molecules of plasticizers in the films.     

Performance in planning: Processes, requirements, and errors.

Planning is not only an aspect of our day-to-day lives, it represents a critical aspect of performance on many high-level tasks. Although few of us would dispute the need for planning, the psychology of planning remains relatively undeveloped. With this point in mind, the intent in the present article was to review the available literature on planning. The authors begin by examining alternative models of planning and delineating their implications for performance. Subsequently, the findings obtained in various studies of planning are reviewed with respect to 8 key questions ranging from when planning is useful to how errors in planning should be minimized. The implications of current answers to these questions are discussed in terms of research needs and development of a more comprehensive theoretical understanding of performance in planning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The paradox of normal neuropsychological function in schizophrenia.

Mounting evidence suggests that compromised neurocognitive function is a core feature of schizophrenia. However, some studies have found neuropsychologically normal schizophrenia patients. To address this apparent contradiction, we blindly rated individual neuropsychological profiles of 75 schizophrenia patients and 91 control participants on the basis of methods developed by L. J. Seidman, S. V. Faraone, W. S. Kremen, J. R. Pepple, M. J. Lyons, and M. T. Tsuang (1993). Almost one-quarter of the patients were classified as neuropsychologically within normal limits (WNL). Despite significantly worse neuropsychological performance, WNL patients had higher estimated premorbid ability than did controls. Compared to a subset of controls matched on overall neuropsychological function, WNL patients had higher estimated premorbid ability and current IQs. Our results favor the view that even neuropsychologically normal schizophrenia patients have compromised cognitive function relative to their presumed expected or premorbid level of intellectual ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of films based on blends of gelatin and poly(vinyl alcohol) cross linked with glutaraldehyde

Both gelatin and poly(vinyl alcohol) (PVA) can be cross linked with glutaraldehyde (GLU). In the case of gelatin, the GLU reacts with each ε-NH2 functional group of adjacent lysine residues, while for PVA, the GLU reacts with two adjacent hydroxyl groups, forming acetal bridges. Thus it can be considered possible to cross link adjacent macromolecules of gelatin and PVA using GLU. In this context, the aims of this work were the development of biodegradable films based on blends of gelatin and poly(vinyl alcohol) cross linked with GLU, and the characterization of some of their main physical and functional properties. All the films were produced from film-forming solutions (FFS) containing 2 g macromolecules (PVA + gelatin)/100 g FFS, 25 g glycerol/100 g macromolecules, and 4 g GLU (25% solution)/100 g FFS. The FFS were prepared with two concentrations of PVA (20 or 50 g PVA/100 g macromolecules) and two reaction temperatures: 90 or 55 °C, applied for 30 min. The films were obtained after drying (30 °C/24 h) and conditioning at 25 °C and 58% of relative humidity for 7 days, and were then characterized. The results for the color parameters, mechanical properties, phase transitions and infrared spectra showed that some chemical modifications occurred, principally for the gelatin. However, in general, all the characteristics of the films were either typical of films based on blends of these macromolecules without cross linking, or slightly higher. A greater improvement in the properties of this material was probably not observed due to the crystallinity of the PVA, which has a melting point above 90 °C. The presence of microcrystals in the polymer chain probably reduced macromolecular mobility, hindering the reaction. Thus more research is necessary to produce biodegradable films with improved properties.     

Binding Mode and Structure–Activity Relationships around Direct Inhibitors of the Nrf2–Keap1 Complex

An X‐ray crystal structure of Kelch‐like ECH‐associated protein (Keap1) co‐crystallised with (1S,2R)‐2‐[(1S)‐1‐[(1,3‐dioxo‐2,3‐dihydro‐1H‐isoindol‐2‐yl)methyl]‐1,2,3,4‐tetrahydroisoquinolin‐2‐carbonyl]cyclohexane‐1‐carboxylic acid (compound (S,R,S)‐ 1 a ) was obtained. This X‐ray crystal structure provides breakthrough experimental evidence for the true binding mode of the hit compound (S,R,S)‐ 1 a , as the ligand orientation was found to differ from that of the initial docking model, which was available at the start of the project. Crystallographic elucidation of this binding mode helped to focus and drive the drug design process more effectively and efficiently.     

Effects of dietary oils and methyl ethyl ketone peroxide onin vivo lipid peroxidation and antioxidants in rat heart and liver

Weanling male Sprague-Dawley rats were fed diets for four weeks which differed in their content of n−6 (corn oil; CO) and n−3 fatty acids (fish oil; FO), but were similar in their content of saturated and monounsaturated fatty acids and vitamin E. At the end of the four-week feeding period, each dietary group was subdivided into two groups. One group received a single placebo injection of α-tocopherol-stripped corn oil (TSCO); the other group received a single injection of the free radical generator, methyl ethyl ketone peroxide (MEKP), in TSCO. Twenty-four hours after injection, the effect of dietary oil and MEKP treatment on endogenous lipid peroxide (LPO) production (measured as methylene blue formed by the “Determiner LPO” assay), glutathione (GSH) and vitamin E content, and fatty acid composition of phosphatidylcholine and phosphatidylethanolamine in heart and liver from unfasted animals were measured. FO-fed rats had significantly heavier hearts and livers, increased levels of n−3 fatty acids in membrane phospholipids, and higher liver LPO levels than CO-fed rats. MEKP treatment resulted in significantly lower body weights and liver GSH levels. The data indicate that dietary n−3 fatty acids increase lipid peroxidation in liver somewhat more than in heart. The study also demonstrates that the effect of induced oxidative stress due to a single dose of MEKP on lipid peroxide formation and antioxidant status in tissues from unfasted animals was independent of the dietary oils.