Cancer is a prominent cause of death globally. Currently, many drugs that are in clinical practice are having a high prevalence of side effect and multidrug resistance. Risk of tumors acquiring ...resistance to chemotherapy (multidrug resistance) remains a significant hurdle to the successful treatment of various types of cancer. Membrane-embedded drug transporters, generally overexpressed in cancer, are the leading cause among multiple mechanisms of multidrug resistance (MDR). P-glycoprotein (P-gp) also MDR1/ABCB1, multidrug resistance associated protein 1 (MRP1/ABCC1), MRP2 and breast cancer resistance protein (BCRP/ABCG2) are considered to be a prime factor for induction of MDR. To date, several chemical substances have been tested in a number of clinical trials for their MDR modulatory activity which are not having devoid of any side effects that necessitates to find newer and safer way to tackle the current problem of multidrug resistance in cancer. The present study systematically discusses the various classes of natural products i.e flavonoids, alkaloids, terpenoids, coumarins (from plants, marine, and microorganisms) as potential MDR modulators and/or as a source of promising lead compounds. Recently a bisbenzyl isoquinoline alkaloid namely tetrandrine, isolated from Chinese herb Stephania tetrandra (Han-Fang-Chi) is in clinical trials for its MDR reversal activity.
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•ABC transporters are major contributors to multidrug resistance in cancer.•Natural products from natural resources can be the fourth generation of MDR modulators.•Flavonoids, terpenoids, alkaloids can be used as MDR modulators.
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•Factors influencing the effective valorization of lignocellulose.•Classification of pretreatments with detailed description of various strategies.•Physical, Chemical, Biological and ...Physico-chemical pretreatment of lignocellulose.•Formation of inhibitory compounds post pre-treatment of lignocellulose.•Strategies for effective removal of inhibitory compounds.
Lignocellulose is a generic term used to describe plant biomass. It is the most abundant renewable carbon resource in the world and is mainly composed of lignin, cellulose and hemicelluloses. Most of the food and food processing industry waste are lignocellulosic in nature with a global estimate of up to 1.3billion tons/year. Lignocellulose, on hydrolysis, releases reducing sugars which is used for the production of bioethanol, biogas, organic acids, enzymes and biosorbents. However, structural conformation, high lignin content and crystalline cellulose hinder its use for value addition. Pre-treatment strategies facilitate the exposure of more cellulose and hemicelluloses for enzymatic hydrolysis. The present article confers about the structure of lignocellulose and how it influences enzymatic degradation emphasising the need for pre-treatments along with a comprehensive analysis and categorisation of the same. Finally, this article concludes with a detailed discussion on microbial/enzymatic inhibitors that arise post pre-treatment and strategies to eliminate them.
In the present review, the recent progress in describing the intricacies of mechanical and thermal properties of all types of graphene- and modified graphene-based polymer nanocomposites has been ...comprehensively examined. The effectiveness of microscopy bouquet for the intrinsic characterization of graphene family and their composites was clearly demonstrated in this research. Furthermore, the utility of the dynamic mechanical analysis and thermo-gravimetric analysis employed for thermal characterization that has been reported by various researchers was exhaustively analyzed in this paper. This research primarily focused on the analyses of several good articles concerned with hybrid graphene composites and the synergetic effect of graphene with other nanofiller to assess its effect on the mechanical properties of its corresponding composites. Such systematic analysis of previous literatures imparted a direction to the researchers about the solution of improved interfacial properties as well as the enhanced dispersion into the vicinity of the matrix. This current research has suggested that the presence of the graphene filler even at very low loadings has shown considerable improvement in the overall mechanical properties of graphene. Further studies to optimize the value of the filler need to be addressed in order to gain complete understanding of the properties of graphene. The potential applications, current challenges, and future perspectives pertaining to these nanocomposites were elaborately discussed in the current study with regard to the multi-scale capabilities and promising developments of the graphene-family-based nanocomposites materials.
As robotics technology evolves, we believe that personal social robots will be one of the next big expansions in the robotics sector. Based on the accelerated advances in this multidisciplinary ...domain and the growing number of use cases, we can posit that robots will play key roles in everyday life and will soon coexist with us, leading all people to a smarter, safer, healthier, and happier existence.
Exchange of patient record over network required a technique to guarantee security and privacy for tele-health services. This paper presents an improved watermarking technique capable of providing ...protection of patient data by embedding multi-watermarks in medical cover image using DWT-SVD domain. Prior to embedding, Hamming code is applied to text watermark in order to reduce channel noise distortion for the sensitive data. After embedding, the watermarked medical image is encrypted then compressed. Out of two encryption method and three compression scheme tested, combination of Chaotic-LZW shows the best performance. However, HyperChaotic-LZW combination is more robust against Gaussian, JPEG compression, speckle noise and histogram equalization attacks. We illustrate the good results in terms of objective and subjective evaluation, and verify its robustness for various attacks while maintaining imperceptibility, security and compression ratio. Experimental results demonstrate that the suggested technique archives high robustness against attacks in comparison to the other scheme for medical images.
To achieve good living standards, it is critical to make high-performance toxic gas sensing devices for public safety, environmental pollutant control, industrial operations, and other applications. ...For this purpose, we demonstrate CuO anchored SnO2 nanostructures for H2S gas sensors. The selectivity was improved by anchoring with CuO for a total 60 s duration at four equal consecutive cycles to achieve good selectivity towards H2S molecules. The pristine CuO shows instability and metallic behaviour when it is exposed to H2S for a longer time. Furthermore, the proposed gas sensor shows good selectivity toward H2S as compared to other gases H2, NO2, CO2, and NH3. The sensing response was measured at around 69 % at the optimal operating temperature of 150°C. It is observed that CuS formation has better selectivity as compared to pristine SnO2 and a slight improvement in sensitivity is observed. As a result, a promising strategy for designing and producing good-performance H2S gas sensors would be to CuO anchor on SnO2 nanostructures. The proposed sensors may be integrated with IoT platforms and used for the detection of H2S in the sewer line and leak detection in the petroleum industry.
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•SnO2 thin film was anchored with CuO at different time duration using RF sputtering for H2S gas sensing.•The sensor exhibits higher sensing response of 69 % at 150 ºC for 100 ppm of H2S with a LoD of 1 ppm.•Comparative analysis was performed for H2S gas detection for both SnO2 and CuO/SnO2 based sensors.•Excellent selectivity and slight improved sensitivity was observed with CuO/SnO2 based gas sensor.
Rheumatoid arthritis (RA) is a chronic systemic, autoimmune and inflammatory disease represented as synovitis, pannus formation, adjacent bone erosions, and joint destruction. The major cells ...involved in the perpetuation of RA pathogenesis are CD4+ T-cells (mainly Th1 cells and Th17 cells), fibroblasts like synoviocytes (FLS), macrophages and B cells. Other autoimmune cells such as dendritic cells, neutrophils, mast cells, and monocytes also contribute to RA pathogenesis. Monocytes are mainly bone marrow (BM) derived cells in the circulation. The chemokine receptors CCR2 and CX3CR1 expressed by monocytes interact with chemokine ligands CCL2 (MCP-1) and CX3CL1 (fractalkine) respectively produced by FLS and this interaction promotes their migration and recruitment into RA synovium. Activated monocytes on their surface exhibit upregulated antigenic expressions such as CD14, CD16, HLA-DR, toll-like receptors (TLRs), and adhesion molecules B1 and B2 integrins. RA monocytes interconnect with other cells in a positive loop manner in the propagation of the rheumatoid process. They skew towards mainly intermediate monocyte subsets (CD14++ CD16+) which produce proinflammatory cytokines such as TNF-α, IL-1β, and IL-6. Moreover, the predominant intermediate monocytes in RA differentiate into M1-macrophages which play a major role in synovial inflammation. Demonstrations suggest monocytes with CD14+ and CD16− expression (classical monocytes?) differentiate to osteoclasts which are the cells responsible for bone erosion in RA synovial joints. Th17 cells induce the production of RANKL by FLS which promotes osteoclastogenesis. Cytokines mainly TNF-α, IL-1β, and IL-6 amplify osteoclastogenesis. Hence, monocytes are the circulating precursors of macrophages and osteoclasts in RA.
To enlighten the identity of monocytes, the antigenic expression on monocyte surface and their cytokines role in RA. We also emphasize about the chemokine receptors expressed by monocytes subsets and chemotaxis of circulating monocytes into RA synovium. Additionally, we review monocytes as the circulating precursors of macrophages and osteoclasts in RA joints and their heterogeneity and plasticity role in RA.
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•The interaction of CCR2,CX3CR1 with CCL2 and fractalkine respectively induces circulating monocytes recruit into RA synovium.•Intermediate monocyte subsets (CD14++CD16+) in peripheral blood and synovium in RA patients produce TNF-α, 1L-1β, IL-6.•Intermediate monocytes differentiate into inflammatory macrophages (M1).•Monocytes subsets with CD14+ and CD16− expression differentiate into osteoclasts and cause bone erosions in RA synovial joints.
Aspergillus nidulans is a filamentous fungus that is a potential resource for industrial enzymes. It is a versatile fungal cell factory that can synthesize various industrial enzymes such as ...cellulases, β-glucosidases, hemicellulases, laccases, lipases, proteases, β-galactosidases, tannases, keratinase, cutinases, and aryl alcohol oxidase. A. nidulans has shown the potential to utilize low-cost substrates such as wheat bran, rice straw, sugarcane bagasse, rice bran, coir pith, black gram residue, and chicken feathers to produce enzymes cost-effectively. A. nidulans has also been known as a model organism for the production of heterologous enzymes. Several studies reported genetically engineered strains of A. nidulans for the production of different enzymes. Native as well as heterologous enzymes of A. nidulans have been employed for various industrial processes.
Due to the scarcity of fossil fuels and to population increases, there is an urgent need for renewable energy sources that can replace petroleum-derived fuels. Lignocellulosic biomass, a renewable ...resource, can be converted to bio-oil by fast pyrolysis and further upgraded to renewable diesel through hydroprocessing. The upgrading of oil by fast pyrolysis is the main focus of this paper. Bio-oil has a higher energy density and heating value than biomass, but it cannot be used in place of petro-diesel as it is highly unstable, polar, and immiscible with hydrocarbons. Thus upgrading is necessary as it removes oxygen-containing compounds from bio-oil. Hydroprocessing was chosen for this review paper as the method of upgrading bio-oil because there are hydrotreating units in place in refineries. To upgrade bio-oil, hydrodeoxygenation (HDO) in the presence of both a catalyst and hydrogen can replace hydrodesulfurization (the removal of sulfur compounds from crude oil). A sulfided NiMo/CoMo catalyst supported on gamma alumina is used as a benchmark catalyst for a hydrodesulfurization reaction in refineries and is considered the reference catalyst for HDO in the production of renewable diesel. The properties of renewable diesel made through hydroprocessing are similar to those of petro-diesel. Catalyst deactivation and techno-economic assessments of the whole pathway are areas that need more attention before renewable diesel can be commercialized. This review paper concentrates on the reaction mechanism in bio-oil upgrading, process parameters, and the limitations of hydroprocessing technology. This paper will be helpful for further modeling of techno-economic analysis in renewable diesel production from lignocellulosic biomass.
Compared to carbon nanotubes (CNTs), graphene possesses high strength due to wrinkled surface texture caused by a high density of surface defects which benefits more contact with the polymer material ...than a rolled-up CNT. In the present review, we have discussed and compared the various properties of CNTs (1-D) and graphene (2-D) obtained in experimental results. The effects of covalent and non-covalent functionalization of CNTs and graphene on the properties of its composites have also been reviewed and compared. A comparative analysis has been carried out between CNTs and graphene-reinforced polymer composites. Furthermore, the synergetic effects of CNTs and graphene hybrid nanofiller on the mechanical properties of polymer composites have also been briefly discussed. Finally, this review concludes with the potential application and future challenges are discussed with regards to filler and their polymer composites.
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