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91.
92.
Selene Elizabeth Herrera-Vzquez Octavio Dubln-García Daniel Arizmendi-Cotero Leobardo Manuel Gmez-Olivn Hariz Islas-Flores María Dolores Hernndez-Navarro Ninfa Ramírez-Durn 《Molecules (Basel, Switzerland)》2022,27(3)
The aim of this work was to evaluate the effect of the concentration of gelatin (G) (3–6 g), whey protein (W) (2.5–7.5 g) and chitosan (C) (0.5–2.5 g) on the physical, optical and mechanical properties of composite edible films (CEFs) using the response surface methodology (RSM), as well as optimizing the formulation for the packaging of foods. The results of the study were evaluated via first- and second-order multiple regression analysis to obtain the determination coefficient values with a good fit (R ˃ 0.90) for each of the response variables, except for the values of solubility and b*. The individual linear effect of the independent variables (the concentrations of gelatin, whey protein and chitosan) significantly affected (p ≤ 0.05) the water vapor permeability (WVP), strength and solubility of the edible films. The WVP of the edible films varied from 0.90 to 1.62 × 10−11 g.m/Pa.s.m2, the resistance to traction varied from 0.47 MPa to 3.03 MPa and the solubility varied from 51.06% to 87%. The optimized values indicated that the CEF prepared with a quantity of 4 g, 5 g and 3 g of gelatin, whey protein and chitosan, respectively, provided the CEF with a smooth, continuous and transparent surface, with L values that resulted in a light-yellow hue, a lower WVP, a maximum strength (resistance to traction) and a lower solubility. The results revealed that the optimized formulation of the CEF of G–W–C allowed a good validation of the prediction model and could be applied, in an effective manner, to the food packaging industry, which could help in mitigating the environmental issues associated with synthetic packaging materials. 相似文献
93.
Mariana Pazos Estefania Dibello Juan Manuel Mesa Dalibor Sames Marcelo Alberto Comini Gustavo Seoane Ignacio Carrera 《Molecules (Basel, Switzerland)》2022,27(3)
The first stage of the drug discovery process involves the identification of small compounds with biological activity. Iboga alkaloids are monoterpene indole alkaloids (MIAs) containing a fused isoquinuclidine-tetrahydroazepine ring. Both the natural products and the iboga-inspired synthetic analogs have shown a wide variety of biological activities. Herein, we describe the chemoenzymatic preparation of a small library of novel N-indolylethyl-substituted isoquinuclidines as iboga-inspired compounds, using toluene as a starting material and an imine Diels–Alder reaction as the key step in the synthesis. The new iboga series was investigated for its potential to promote the release of glial cell line-derived neurotrophic factor (GDNF) by C6 glioma cells, and to inhibit the growth of infective trypanosomes. GDNF is a neurotrophic factor widely recognized by its crucial role in development, survival, maintenance, and protection of dopaminergic neuronal circuitries affected in several neurological and psychiatric pathologies. Four compounds of the series showed promising activity as GDNF releasers, and a leading structure (compound 11) was identified for further studies. The same four compounds impaired the growth of bloodstream Trypanosoma brucei brucei (EC50 1–8 μM) and two of them (compounds 6 and 14) showed a good selectivity index. 相似文献
94.
Pedro L. R. Guedes Carolina P. F. Carvalho Adriana A. F. Carbonel Manuel J. Simes Marcelo Y. Icimoto Jair A. K. Aguiar Maria Kouyoumdjian Marcos L. Gazarini Marcia R. Nagaoka 《Molecules (Basel, Switzerland)》2022,27(3)
During liver fibrogenesis, there is an imbalance between regeneration and wound healing. The current treatment is the withdrawal of the causing agent; thus, investigation of new and effective treatments is important. Studies have highlighted the action of chondroitin sulfate (CS) in different cells; thus, our aim was to analyze its effect on an experimental model of bile duct ligation (BDL). Adult Wistar rats were subjected to BDL and treated with CS for 7, 14, 21, or 28 days intraperitoneally. We performed histomorphometric analyses on Picrosirius-stained liver sections. Cell death was analyzed according to caspase-3 and cathepsin B activity and using a TUNEL assay. Regeneration was evaluated using PCNA immunohistochemistry. BDL led to increased collagen content with corresponding decreased liver parenchyma. CS treatment reduced total collagen and increased parenchyma content after 21 and 28 days. The treatment also promoted changes in the hepatic collagen type III/I ratio. Furthermore, it was observed that CS treatment reduced caspase-3 activity and the percentage of TUNEL-positive cells after 14 days and cathepsin B activity only after 28 days. The regeneration increased after 14, 21, and 28 days of CS treatment. In conclusion, our study showed a promising hepatoprotective action of CS in fibrogenesis induced by BDL. 相似文献
95.
Pablo R. Beltrán Juan Miguel Gil Rafael Rodríguez Guadalupe Espinosa Manuel D. Barriga-Carrasco 《X射线光谱测定》2020,49(1):173-176
The purpose of this work is to study the interaction between an ion beam and a doped deuterium-tritium (DT) plasma in a fast ignition nuclear fusion context. In order to analyze the influence of the dopants in the interaction process, we present a physical model to carry out spatial-temporal simulations of the stopping of an ion beam interacting with a doped plasma target, the plasma heating processes, and the formation of the ignition regions. We perform a set of numerical experiments where different concentrations of dopants are added to a fully ionized DT plasma. These simulations allow us to characterize the increase in the stopping power and the maximum temperatures achieved with the presence of impurities, as well as the reduction of the heated and ignition regions. This reduction in the ignition region indicates difficulties for the formation of an efficient hot spot when there are dopants in the DT plasma. 相似文献
96.
Jos Mahía Miguel A. Maestro Miguel Vzquez Manuel R. Bermejo Ana M. Gonzlez Marcelino Maneiro 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):347-348
The structure of the title compound, C30H30N4O4S2, is highly conditioned in the solid state by two strong N—H?N interactions. The values of the distances between the aminic N atoms [5.865 (3) Å] and the iminic N atoms [2.930 (4) Å], in conjunction with the long distance between the S atoms of the two tosyl groups [7.673 (1) Å], suggest that when the molecule acts as a ligand it will provide a single cavity for N4 coordination to the metal centre. 相似文献
97.
Borja Vargas David Cuesta-Frau Paula Gonzlez-Lpez María-Jos Fernndez-Cotarelo
scar Vzquez-Gmez Ana Cols Manuel Varela 《Entropy (Basel, Switzerland)》2022,24(4)
Body temperature is usually employed in clinical practice by strict binary thresholding, aiming to classify patients as having fever or not. In the last years, other approaches based on the continuous analysis of body temperature time series have emerged. These are not only based on absolute thresholds but also on patterns and temporal dynamics of these time series, thus providing promising tools for early diagnosis. The present study applies three time series entropy calculation methods (Slope Entropy, Approximate Entropy, and Sample Entropy) to body temperature records of patients with bacterial infections and other causes of fever in search of possible differences that could be exploited for automatic classification. In the comparative analysis, Slope Entropy proved to be a stable and robust method that could bring higher sensitivity to the realm of entropy tools applied in this context of clinical thermometry. This method was able to find statistically significant differences between the two classes analyzed in all experiments, with sensitivity and specificity above 70% in most cases. 相似文献
98.
Illanes A Wilson L Caballero E Fernández-Lafuente R Guisán JM 《Applied biochemistry and biotechnology》2006,133(3):189-202
Crosslinked enzyme aggregates (CLEAs) of a partially purified penicillin acylase from a recombinant Escherichia coli strain have been produced as a novel type of biocatalysts well endowed to perform in organic media. Different protein precipitants
were studied and glutaraldehyde was used as the crosslinking agent. Precipitation curves were obtained for all precipitants
to determine the concentrations at which all the protein precipitated out of the solution. The effect of the glutaraldehyde-to-protein
ratio was studied with respect to process recovery and the specific activity and stability of the biocatalyst. Recovery of
penicillin acylase activity was moderately high, about 50%; major losses of enzyme activity were produced at the precipitation
step. Specific activities of all CLEAs were very high, which is one of the advantages of using nonsupported biocatalysts.
Ammonium sulfate and tert-butyl alcohol were the best precipitants at a glutaraldehyde-protein mass ratio of 2 and were selected to perform the kinetically
controlled synthesis of ampicillin in 60% (v/v) ethylene glycol medium. At comparable conversion yields, volumetric and specific
antibiotic productivity were much higher for CLEAs than for carrier-bound penicillin acylases. 相似文献
99.
The behavior of the polarization in a microscopic statistical model for a thin film relaxor placed between two metallic electrodes is studied by numerical simulations. Depolarization fields different from zero, due to a non-perfect compensation of surface charges at the metallic electrodes, are taken into account. Different thicknesses and different values of the compositional charge disorder density for the relaxor are considered. Depolarization field is found to be extremely attenuated for large values of the number density of charge carriers in the relaxor. In such a case, field attenuation allows for the existence of a homogeneous ferroelectric ground state. 相似文献
100.