Several reports have revealed the superior biological activity of metal ion-flavonoid complexes when compared with the parent flavonoid. Among the different metal ions explored, vanadium and its ...compounds are in the forefront because of their anticancer and antidiabetic properties. However, the toxicity of vanadium-based ions and their inorganic derivatives limits their therapeutic applications. Complexation of vanadium with flavonoids not only reduces its adverse effects but also augments its biological activity. This Review discusses the nature of coordination in vanadium–flavonoid complexes, their structure–activity correlations, with special emphasis on their therapeutic activities. Several investigations suggest that the superior biological activity of vanadium complexes arise because of their ability to regulate metabolic pathways distinct from those acted upon by vanadium alone. These studies serve to decipher the underlying molecular mechanism of vanadium–flavonoid complexes that can be explored further for generating a series of novel compounds with improved pharmacological and therapeutic performance.
Tissue engineering promises to be an effective strategy that can overcome the lacuna existing in the current pharmacological and interventional therapies and heart transplantation. Heart failure ...continues to be a major contributor to the morbidity and mortality across the globe. This may be attributed to the limited regeneration capacity after the adult cardiomyocytes are terminally differentiated or injured. Various strategies involving acellular scaffolds, stem cells, and combinations of stem cells, scaffolds and growth factors have been investigated for effective cardiac tissue regeneration. Recently, injectable hydrogels have emerged as a potential candidate among various categories of biomaterials for cardiac tissue regeneration due to improved patient compliance and facile administration via minimal invasive mode that treats complex infarction. This review discusses in detail on the advances made in the field of injectable materials for cardiac tissue engineering highlighting their merits over their preformed counterparts.
•Nanomaterial interface helps in developing highly sensitive biosensors.•Toxicity mechanism of heavy metal ions on cells is highlighted.•Metal ions inhibit enzymes and induce reactive oxygen species ...in cells.•Challenges on sensing various species of metals using nano-interface are discussed.•Detection of Ag, As, Cd, Cr, Cu, Hg, Pb, and Zn ions in water sources is reported.
Most of the metal ions are carcinogens and lead to serious health concerns by producing free radicals. Hence, fast and accurate detection of metal ions has become a critical issue. Among various metal ions arsenic, cadmium, lead, mercury and chromium are considered to be highly toxic. To detect these metal ions, electrochemical biosensors with interfaces such as microorganisms, enzymes, microspheres, nanomaterials like gold, silver nanoparticles, CNTs, and metal oxides have been developed. Among these, nanomaterials are considered to be most promising, owing to their strong adsorption, fast electron transfer kinetics, and biocompatibility, which are very apt for biosensing applications. The coupling of electrochemical techniques with nanomaterials has enhanced the sensitivity, limit of detection, and robustness of the sensors. In this review, toxicity mechanisms of various metal ions and their relationship towards the induction of oxidative stress have been summarized. Also, electrochemical biosensors employed in the detection of metal ions with various interfaces have been highlighted.
Biomechanical performance of functional cartilage is executed by the exclusive anisotropic composition and spatially varying intricate architecture in articulating ends of diarthrodial joint. ...Osteochondral tissue constituting the articulating ends comprise superfical soft cartilage over hard subchondral bone sandwiching interfacial soft–hard tissue. The shock-absorbent, lubricating property of cartilage and mechanical stability of subchondral bone regions are rendered by extended chemical structure of glycosaminoglycans and mineral deposition, respectively. Extracellular matrix glycosaminoglycans analogous polysaccharides are major class of hydrogels investigated for restoration of functional cartilage. Recently, injectable hydrogels have gained momentum as it offers patient compliance, tunable mechanical properties, cell deliverability, and facile administration at physiological condition with long-term functionality and hyaline cartilage construction. Interestingly, facile modifiable functional groups in carbohydrate polymers impart tailorability of desired physicochemical properties and versatile injectable chemistry for the development of highly potent biomimetic in situ forming scaffold. The scaffold design strategies have also evolved from single component to bi- or multilayered and graded constructs with osteogenic properties for deep subchondral regeneration. This review highlights the significance of polysaccharide structure-based functions in engineering cartilage tissue, injectable chemistries, strategies for combining analogous matrices with cells/stem cells and biomolecules and multicomponent approaches for osteochondral mimetic constructs. Further, the rheology and precise spatiotemporal positioning of cells in hydrogel bioink for rapid prototyping of complex three-dimensional anisotropic cartilage have also been discussed.
Cerebral ischemia is a deadly condition that arises due to blockage of the blood vessels in the brain leading to oxygen deficiency thereby arresting brain functions and resulting in death or ...permanent impairment. Though a myriad of factors has been proposed to cause cerebral ischemia, it has been generally regarded as an old age-associated malady. However, unhealthy diet, stressful lifestyle and deteriorating environment quality has dramatically reduced the age on onset as well as the number of victims in recent years. Hence, there exists a need for prompt and effective therapeutic strategies for immediate as well as long-term damage control and maintenance of the functions of the brain, as well as early and accurate diagnosis of the risk of stroke or extent of damage after stroke. The physiological barriers further complicate the development of therapeutic and diagnostic interventions for cerebral stroke. The advent of nanotechnology has initiated new vistas for more effective and superior therapeutic and imaging modalities for management of cerebral ischemia. This review provides an overview on the current knowledge on the mechanism and causative factors of cerebral ischemia, drawbacks of conventional therapy as well as molecular targets that are being explored for stroke therapy. The review also discusses in detail the advances made using nano-interventions for therapy and imaging of stroke-affected regions along with their pros and cons. Emergent multi-functional nanoparticles for stroke management have also been reviewed.
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The industrial and technological advancements in the world have also contributed to the rapid deterioration in the environment quality through introduction of obnoxious pollutants ...that threaten to destroy the subtle balance in the ecosystem. The environment contaminants cause severe adverse effects to humans, flora and fauna that are mostly irreversible. Chief among these toxicants is arsenic, a metalloid, which is considered among the most dangerous environmental toxins that leads to various diseases which affect the quality of life even when present in small quantities. Treatment of arsenic-mediated disorders still remains a challenge due to lack of effective options. Chelation therapy has been the most widely used method to detoxify arsenic. But this method is associated with deleterious effects leading various toxicities such as hepatotoxicity, neurotoxicity and other adverse effects. It has been discovered that indigenous drugs of plant origin display effective and progressive relief from arsenic-mediated toxicity without any side-effects. Further, these phytochemicals have also been found to aid the elimination of arsenic from the biological system and therefore can be more effective than conventional therapeutic agents in ameliorating arsenic-mediated toxicity. This review presents an overview of the toxic effects of arsenic and the therapeutic strategies that are available to mitigate the toxic effects with emphasis on chelation as well as protective and detoxifying activities of different phytochemicals and herbal drugs against arsenic. This information may serve as a primer in identifying novel prophylactic as well as therapeutic formulations against arsenic-induced toxicity.
The consumption of carbosulfan-contaminated rice affects the immune and lymphocyte response, germinal centers in the spleen, plasma cells in popliteal lymphoid nodes, bone marrow cells and ...granulocyte-macrophage progenitor cells. Towards this, a highly sensitive acetylcholinesterase (AChE) cyclic voltammetric biosensor based on zinc oxide (ZnO) nanocuboids modified platinum (Pt) electrode has been successfully developed. The Pt/ZnO/AChE/Chitosan bio-electrode was employed for the electrochemical detection of carbosulfan in rice sample. Under optimum conditions, the Pt/ZnO/AChE/Chitosan bio-electrode detected carbosulfan ranging from 5 to 30nM with a detection limit (LOD) of 0.24nM. The developed Pt/ZnO/AChE/Chitosan bio-electrode showed good recovery (99.06–100.96%), thus providing a promising tool for analysis of carbosulfan in rice sample.
•Pt/ZnO/AChE/Chitosan bioelectrode was used as effective sensing platform.•Electrochemical properties of developed bioelectrode were deeply characterized.•The calibration method depicted appreciable precision, accuracy and recovery.•The developed biosensor was applied to determinate carbosulfan in rice sample.•Correlation between predicted and added carbosulfan was very good.
Tissue engineering scaffolds produced by electrospinning feature a structural similarity to the natural extracellular matrix. Polymer blending is one of the effective methods to provide new and ...desirable biocomposites for tissue engineering applications. In this study chitosan was blended with gelatin and the effect of processing parameters of electrospinning and the solution properties of the polymer on the morphology of the fibers obtained were investigated. The morphology of the electrospun chitosan, gelatin and the chitosan-gelatin blend were characterized using a scanning electron microscope (SEM). The miscibility of the blend was determined using a SEM, and differential scanning calorimetry (DSC) Fourier transform Infrared spectrometer (FTIR). Further the tensile properties of the blend nanofibers were studied and compared with chitosan and gelatin fibers. In this study we have been able to electrospin defect-free chitosan, gelatin and chitosan-gelatin blend nanofibers with smooth morphology and diameter ranging from 120 to 200 nm, 100 to 150 nm, and 120-220 nm, respectively by optimizing the process and solution parameters. Chitosan and gelatin formed completely miscible blends as evidenced from DSC and FTIR measurements. The tensile strength of the chitosan-gelatin blend nanofibers (37.91 +/- 4.42 MPa) was significantly higher than the gelatin nanofibers (7.23 +/- 1.15 MPa) (p < 0.05) and comparable with that of normal human skin. Thus the novel chitosan-gelatin blend nanofiber system has potential application in skin regeneration.
Simultaneous determination of Cd(II), Pb(II), As(III) and Hg(II) metal ions was carried out based on the synergistic effect of graphene oxide (GO) textured with redox active ruthenium(II) bipyridine ...complex (Ru(bpy)32+). Ru(bpy)32+-GO nanocomposite on the modified gold (Au) electrode acts as an electrocatalyst and favours the sensitive and selective detection of metal ions. Also, it exhibited an enhanced electron transfer rate with a low solution resistance examined by cyclic voltammetry and impedance analysis. The inherent electrochemical and electrocatalytic behaviours of Ru(bpy)32+-GO on gold electrode were demonstrated for simultaneous detection of heavy metal ions in water matrix. The proposed sensor exhibited a higher sensitivity towards Cd(II), Pb(II), As(III) and Hg(II) metal ions with a lowest detection limit of 2.8, 1.41, 2.3 and 1.6nM respectively. The observed detection limits were less than the World Health Organization standards and hence the developed sensor can be deployed for detecting heavy metal ions in water bodies. Simultaneous electrochemical detection of heavy metal ions in river and tap water was carried out using the developed sensor and the observed results were validated with atomic absorption spectroscopy.
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•GO and Ru(bpy)32+-GO nanocomposite were synthesized and characterized.•Ru(bpy)32+-GO modified Au electrode provides a better electron transfer process.•Catalytic activity of Ru(bpy)32+-GO was utilized to detect heavy metal ions.•Simultaneous detection of heavy metal ions in water matrix was achieved.•Developed sensor was validated using AAS.
Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to ...regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves.
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