Synthesis, crystal structure and biological activity of beta-carboline based selective CDK4-cyclin D1 inhibitors

The design, synthesis and biological activity of a series of non-planar dihydro-beta-carboline and beta-carboline-based derivatives of the toxic anticancer agent fascaplysin is presented. We show these compounds to be selective inhibitors of CDK4 over CDK2 with an IC50 (CDK4-cyclin D1) = 11 micromol for the best compound in the series 4d. The crystallographic analysis of some of the compounds synthesised (3b/d and 4a-d) was carried out, in an effort to estimate the structural similarities between the designed inhibitors and the model compound fascaplysin.     

Surface-enhanced Raman spectroscopic study of 1,4-phenylene diisocyanide adsorbed on gold and platinum-group transition metal electrodes

Self-assembled monolayers of 1, 4-phenylene diisocyanide (PDI) were formed on Au and Pt-group transition metals and examined by surface-enhanced Raman spectroscopy under controlled applied potential. On all of the metals examined, PDI adsorbs in an edge-on manner, with one NC group bound to the surface and the other pointing away from the surface. The N-C stretching frequency (nu(NC)) suggests that depending on the metal, PDI adsorbs on different binding sites: terminal sites on Au, both terminal and bridging on Rh and Pt, and predominantly 3-fold hollow sites for Pd. This binding site preference can be understood in terms of the difference in d-band center energy and d-orbital filling among the metals. The applied potential affects the N-C bonding differently as inferred from the potential dependence of nu(NC). On Au, Rh, and Pd, the nu(NC) increases linearly with the applied potential, yielding a Stark tuning slope, dnu(NC)/dE, of 25, 12, and 10 cm(-1)/V, respectively. On Pt, the nu(NC) is nearly independent of the applied potential. On all of the metals studied, the frequencies of benzene ring vibration modes are not dependent on the applied potential, consistent with the edge-on orientation in which the ring does not directly interact with the surface. Several ring vibrations are, however, sensitive to the nature of metal substrate due to different binding sites involved. The ability of the free NC group to function as an anchoring point is demonstrated by the attachment of gold nanoparticles on PDI-covered Au and Pd. The study provides useful NC-metal bonding information for isocyanide-based molecular electronic developments.     

Arrays of lipid bilayers and liposomes on patterned polyelectrolyte templates

This paper presents novel methods to produce arrays of lipid bilayers and liposomes on patterned polyelectrolyte multilayers. We created the arrays by exposing patterns of poly(dimethyldiallylammonium chloride) (PDAC), polyethylene glycol (m-dPEG) acid, and poly(allylamine hydrochloride) (PAH) on polyelectrolyte multilayers (PEMs) to liposomes of various compositions. The resulting interfaces were characterized by total internal reflection fluorescence microscopy (TIRFM), fluorescence recovery after pattern photobleaching (FRAPP), quartz crystal microbalance (QCM), and fluorescence microscopy. Liposomes composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dioleoyl-sn-glycero-3-phosphate (monosodium salt) (DOPA) were found to preferentially adsorb on PDAC and PAH surfaces. On the other hand, liposome adsorption on sulfonated poly(styrene) (SPS) surfaces was minimal, due to electrostatic repulsion between the negatively charged liposomes and the SPS-coated surface. Surfaces coated with m-dPEG acid were also found to resist liposome adsorption. We exploited these results to create arrays of lipid bilayers by exposing PDAC, PAH and m-dPEG patterned substrates to DOPA/DOPC vesicles of various compositions. The patterned substrates were created by stamping PDAC (or PAH) on SPS-topped multilayers, and m-dPEG acid on PDAC-topped multilayers, respectively. This technique can be used to produce functional biomimetic interfaces for potential applications in biosensors and biocatalysis, for creating arrays that could be used for high-throughput screening of compounds that interact with cell membranes, and for probing, and possibly controlling, interactions between living cells and synthetic membranes.     

Monodisperse and highly active PtNi nanoparticles for O2 reduction

Monodisperse PtNi nanoparticles with various compositions were synthesized by a wet-chemical approach. After electrochemical dissolution of Ni on the particle surface, these particles exhibit a 20–30-fold enhancement in O₂ reduction activity as compared to the commercial Pt/C catalysts.     

Painlevé analysis, Lie symmetries and exact solutions for (2+1)-dimensional variable coefficients Broer-Kaup equations

A (2+1) dimensional Broer-Kaup system which is obtained from the constraints of the KP equation is of importance in mathematical physics field. In this paper, the Painlevé analysis of (2+1)-variable coefficients Broer-Kaup (VCBK) equation is performed by the Weiss-Kruskal approach to check the Painlevé property. Similarity reductions of the VCBK equation to one-dimensional partial differential equations including Burger’s equation are investigated by the Lie classical method. The Lie group formalism is applied again on one of the investigated partial differential equation to derive symmetries, and the ordinary differential equations deduced from the optimal system of subalgebras are further studied and some exact solutions are obtained.     

Rediscovering the Therapeutic Potential of Agarwood in the Management of Chronic Inflammatory Diseases

The inflammatory response is a central aspect of the human immune system that acts as a defense mechanism to protect the body against infections and injuries. A dysregulated inflammatory response is a major health concern, as it can disrupt homeostasis and lead to a plethora of chronic inflammatory conditions. These chronic inflammatory diseases are one of the major causes of morbidity and mortality worldwide and the need for them to be managed in the long term has become a crucial task to alleviate symptoms and improve patients’ overall quality of life. Although various synthetic anti-inflammatory agents have been developed to date, these medications are associated with several adverse effects that have led to poor therapeutic outcomes. The hunt for novel alternatives to modulate underlying chronic inflammatory processes has unveiled nature to be a plentiful source. One such example is agarwood, which is a valuable resinous wood from the trees of Aquilaria spp. Agarwood has been widely utilized for medicinal purposes since ancient times due to its ability to relieve pain, asthmatic symptoms, and arrest vomiting. In terms of inflammation, the major constituent of agarwood, agarwood oil, has been shown to possess multiple bioactive compounds that can regulate molecular mechanisms of chronic inflammation, thereby producing a multitude of pharmacological functions for treating various inflammatory disorders. As such, agarwood oil presents great potential to be developed as a novel anti-inflammatory therapeutic to overcome the drawbacks of existing therapies and improve treatment outcomes. In this review, we have summarized the current literature on agarwood and its bioactive components and have highlighted the potential roles of agarwood oil in treating various chronic inflammatory diseases.     

One-pot hydrothermal preparation of hierarchical manganese oxide nanorods for high-performance symmetric supercapacitors

An eco-friendly, new, and controllable approach for the preparation of manganese oxide(a-MnO₂) nanorods has been introduced using hydrothermal reaction for supercapacitor application. The in-depth crystal structure analysis of α-MnO₂ is analyzed by X-ray Rietveld refinement by using Full Prof program with the help of pseudo-Voigt profile function. The developed a-MnO₂ electrode attains a remarkable capacitance of 577.7 F/g recorded at a current density value of 1...     

In Vitro Anticancer Screening,Molecular Docking and Antimicrobial Studies of Triazole-Based Nickel(II) Metal Complexes

Herein we describe the synthesis of a series of nickel(II) complexes (C1–C3) with Schiff bases (HL1–HL3) derived from 4-amino-5-mercapto-3-methyl-1,2,4-triazole and ortho/meta/para-nitrobenzaldehyde having composition [Ni(L)₂(H₂O)₂]. The obtained ligands and their complexes were characterized using physico-chemical techniques viz., elemental analysis, magnetic moment study, spectral (electronic, FT-IR, 1H-NMR) and thermal analysis. The elemental analysis and spectral analysis revealed that Schiff bases behave as monoanionic bidentate ligands towards the Ni(II) ion. Whereas, the magnetic moment study suggested the octahedral geometry of all the Ni(II) complexes. The thermal behavior of the complexes has been studied by thermogravimetric analysis and agrees well with the composition of complexes. Further, the biological activities such as antimicrobial and antifungal studies of the Schiff bases and Ni(II) complexes have been screened against bacterial species (Staphylococcus aureus and Pseudomonas aeruginosa) and fungal species (Aspergillus niger and Candida albicans) activity by MIC method, the results of which revealed that metal complexes exhibited significant antimicrobial activities than their respective ligands against the tested microbial species. Furthermore, the molecular docking technique was employed to investigate the active sites of the selected protein, which indeed helped us to screen the potential anticancer agents among the synthesized ligand and complexes. Further, these compounds have been screened for their in vitro anticancer activity using OVCAR-3 cell line. The results revealed that the complexes are more active than the ligands.     

Synthesis of 1D β-MnO2 for high-performance supercapacitor application

Journal of Solid State Electrochemistry - Electrochemical supercapacitors (ESs) still need to overcome development obstacles in order to realize their full potential while being acknowledged as a...