Rationally designed curcumin laden glycopolymeric nanoparticles: Implications on cellular uptake and anticancer efficacy

Overexpression of glucose transport proteins (GLUTs) plays a pivotal role in the survival of cancer cells. Hence, targeting GLUTs receptors using glucose-based polymers can fill up the lacuna of cancer treatment by confining the dissemination and accumulation of chemotherapeutic drugs on cancer cells. The present study addressed the preparation of glycohomopolymer (PMG), PEG-based di- (PEG-b-PMG) and tri-block (PMG-b-PEG-b-PMG) polymers using atom transfer radical polymerization and their potential in the development of novel nanoparticulate drug delivery system. Curcumin-loaded glycopolymer nanoparticles were fabricated by nanoprecipitation method and investigated for various physicochemical parameters such as particle size, zeta potential, polydispersity index, drug loading, morphology, and dissolution profile. Homoglycopolymer nanoparticles exhibited lower average particle size (240.16 ± 21.41 nm), higher zeta potential (−28.72 ± 4.25 mV), and entrapment efficiency (74.61 ± 5.03%) compared to their block copolymer counterparts. Optimized formulation exhibited diffusion and dissolution-controlled drug release behavior. In vitro cell line studies demonstrated significantly superior cytotoxicity, clonogenic inhibitory and cellular uptake potential in MCF-7 cells besides receptor recognizing property of optimized curcumin nanoparticulate formulation compared to free curcumin. These findings elucidate that curcumin homoglucopyranoside nanocarriers can be a promising drug delivery option for effective management of breast cancer. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48954.     

Combining evidences from excitation source and vocal tract system features for Indian language identification using deep neural networks

In this paper, a combination of excitation source information and vocal tract system information is explored for the task of language identification (LID). The excitation source information is represented by features extracted from linear prediction (LP) residual signal called the residual cepstral coefficients (RCC). Vocal tract system information is represented by the mel frequency cepstral coefficients (MFCC). In order to incorporate additional temporal information, shifted delta cepstra (SDC) are computed. An LID system is built using SDC over both MFCC and RCC features individually and evaluated based on their equal error rate (EER). Experiments have been performed on a dataset consisting of 13 Indian languages with about 115 h for training and 30 h for testing using a deep neural network (DNN), DNN with attention (DNN-WA) and a state-of-the-art i-vector system. DNN-WA outperforms the baseline i-vector system. An EER of 9.93 and 6.25% are achieved using RCC and MFCC features respectively. By combining evidence from both features using a late fusion mechanism, an EER of 5.76% is obtained. This result indicates the complementary nature of the excitation source information to that of the widely used vocal tract system information for the task of LID.     

Temperature-induced strain mediated magnetization changes in NiFe2O4/BaTiO3 heterostructure

Herein, we report the temperature-induced magnetization changes of NiFe₂O₄ thin film, which is coated over a ferroelectric BaTiO₃ ceramic substrate. The solid-state reaction method was adopted for the preparation of ferroelectric BaTiO₃ (BT) substrate, whereas NiFe₂O₄ (NFO) film was deposited by spin-coating method. Rietveld refinement revealed that BT substrate has a tetragonal (P4mm) crystal system along with a minor orthorhombic phase (Amm2) at room temperature. The GIXRD analysis confirms the phase purity of NFO/BT heterostructure. Polarization hysteresis with respect to electric field (P-E loop) and the temperature-dependent dielectric measurement of BT substrate demonstrate its typical ferroelectric and phase transition behavior, respectively. Magnetization hysteresis loops were recorded for the NFO/BT heterostructure at 150, 240 and 300?K. A significant increase in the remnant magnetization (M_R) and coercive field (H_C) of NFO film are noticed while cooling the heterostructure below 300?K. Variation in the magnetization of NFO film corresponds to the change in the structural phase transition (Amm2 at 240?K and R3c at 150?K) of BT while cooling below RT. The interfacial strain mediated coupling is the primary mechanism attributed to the temperature-induced changes in the magnetization of NFO/BT heterostructure.     

Dehydration of 1,4-dioxane by pervaporation using crosslinked calcium alginate-chitosan blend membranes

Summary  Sodium alginate (SA) and chitosan (CS) blended membranes were crosslinked with maleic anhydride (MA) for the separation of 1,4-dioxane/water mixtures at 30 °C by pervaporation (PV). The membranes were characterized by Fourier transform infrared (FTIR) analysis and Ion Exchange Capacity (IEC) to verify the crosslinking. Thermogravimetric analysis (TGA) and X-ray diffraction (XRD) pattern were used to observe the thermal degradation and crystalline nature of the membrane respectively. The membrane performance was studied by calculating flux, selectivity, and pervaporation separation index. Sorption studies were carried out to evaluate the extent of interaction and degree of swelling of the membranes in pure liquids as well as in binary mixtures. The effects of experimental parameters such as feed composition, membrane thickness, and permeate pressure on separation performance of the crosslinked membranes were determined. The experimental result suggested that the membrane has a good potential for breaking the aqueous azeotrope 1,4-dioxane.     

Synthesis and Biological Evaluation of (−) and (+)-Spiroleucettadine and Analogues

A second-generation enantiospecific synthesis of spiroleucettadine is described. The original reported antibacterial activity was not observed when the experiment was repeated on the synthetic samples; however, significant anti-proliferative activity was uncovered for both enantiomers of spiroleucettadine. Comparison of the optical rotational data and ORD-CD spectra of both enantiomers and the reported spectrum from the natural source have not provided a definitive answer regarding the absolute stereochemistry of naturally occurring spiroleucettadine. Efforts then focussed on alteration at the C-4 and C-5 positions of the slightly more active (−)-spiroleucettadine. Ten analogues were synthesised, with three analogues found to possess similar anti-proliferative profiles to spiroleucettadine against the H522 lung cancer cell line.     

Hall effects on MHD chemically reacting flow of second grade fluid past a vertical porous plate

The scrutiny of the consequences of radiation-absorption, chemical reaction impacts on unsteady magnetohydrodynamics heat and mass transportation laminar flow of a gelatinous, electrical conducting by the heat generation or absorption second grade fluid embedded past a half-unlimited porous surface within a gyratory structure taking Hall effects into account have been discussed. The plate is assumed to as in the motion by the invariable velocity contained by the direction of fluid movement. A uniform magnetic field performed at perpendicular to the porous plate; this is engrossing the fluid with the suction velocity changing with definite instants of time. The corresponding dimensionless governing equations of current configuration are solved by making use of perturbation technique with reference to harmonic and nonharmonic idioms. The velocity, temperature, and concentration profiles are discussed and examined with references to various governing parameters in detail. The results are verified with the published work. The velocity components are increased with increasing permeability and Hall parameters. It is noticed that practical application of Hall effects is as, washing machine dial to select the type of washing moves very smoothly. This problem has also applications in biomedical and aerospace engineering.     

Investigation on the corrosion resistance of bagasse-rice husk-wood ash blended cement concrete by impressed voltage

In this study, the compressive strength, the durability to chloride penetration and the corrosion of concrete containing bagasse-rice husk-wood ash (BRWA) were tested. Normal strength concrete with water to binder ratio (w/b) of 0.45 and 0.60 were used. The Portland cement was partially replaced with BRWA at the dosage of 10% and 20% by weight of binder. For concrete with w/b of 0.60, the replacement level of 40% was also tested. The chloride penetration resistance of the concretes was evaluated using the measurement of non-steady state chloride diffusion coefficient by accelerated salt ponding. The accelerated corrosion test by impressed voltage (ACTIV) was also performed to verify the findings and to investigate the characteristics of corrosion in terms of the initial current, the time of initial crack, and the weight loss of embedded steel.From the experiment, it was found that the concrete with 20% BRWA had the highest gain of compressive strength at the ages ranging from 7 to 180 days. The results of the experiments of accelerated salt ponding were in good agreement and conformed with ACTIV. The increase of the incorporation of the BRWA reduced the chloride penetration. The diffusion coefficient was reduced by 30–40% and 65–70% for concrete containing 10% BRWA and 20% BRWA compared to control concrete. The results of ACTIV also indicated that the initial current and the weight loss of embedded steel reduced and the time of initial crack increased with the increase in the replacement level of BRWA.     

Antibiofilm and quorum sensing inhibitory potential of Cuminum cyminum and its secondary metabolite methyl eugenol against Gram negative bacterial pathogens

Quorum sensing inhibitory (QSI) activity of common South Indian spices and vegetables were evaluated using the bacterial model Chromobacterium violaceum. Among the 22 samples tested the QSI compound present in the methanolic extract of Cuminum cyminum at 2 mg/ml inhibited violacein production in C. violaceum. Further, the outcome of the present investigation reveals that C. cyminum extract strongly interferes with acyl homoserine lactone (AHL) regulated physiological functions coupled with biofilm formation such as flagellar motility and exopolysaccharides (EPS) production. It promotes the loosening of biofilm architecture and powerfully inhibits in vitro biofilm formation in Pseudomonas aeruginosa PAO1, Proteus mirabilis and Serratia marcescens at sub-MIC levels. The result of molecular docking analysis attributes the QSI activity exhibited by C. cyminum to methyl eugenol (ME). The ability of ME to interfere with quorum sensing (QS) systems of various Gram-negative bacterial pathogens comprising diverse AHL molecules was also assessed and ME was found to reduce the AHL dependent production of violacein, bioluminescence and biofilm formation.     

Removal of hexavalent chromium from wastewater using a new composite chitosan biosorbent

A new composite chitosan biosorbent was prepared by coating chitosan, a glucosamine biopolymer, onto ceramic alumina. The composite bioadsorbent was characterized by high-temperature pyrolysis, porosimetry, scanning electron microscopy, and X-ray photoelectron spectroscopy. Batch isothermal equilibrium and continuous column adsorption experiments were conducted at 25 degrees C to evaluate the biosorbent for the removal of hexavalent chromium from synthetic as well as field samples obtained from chrome plating facilities. The effect of pH, sulfate, and chloride ion on adsorption was also investigated. The biosorbent loaded with Cr(VI) was regenerated using 0.1 M sodium hydroxide solution. A comparison of the results of the present investigation with those reported in the literature showed that chitosan coated on alumina exhibits greater adsorption capacity for chromium(VI). Further, experimental equilibrium data were fitted to Langmuir and Freundlich adsorption isotherms, and values of the parameters of the isotherms are reported. The ultimate capacity obtained from the Langmuir model is 153.85 mg/g chitosan.