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The pathological levels of reactive oxygen species (ROS) and oxidative stress has been recognized as a critical driver for inflammatory disorders. Apoptosis signal-regulating kinase 1 (ASK1) has been reported to be activated by intracellular ROS and its inhibition leads to a down regulation of p38-and JNK-dependent signaling. ASK1 inhibitors are reported to have the potential to treat clinically important inflammatory pathologies including liver, pulmonary and renal disorders. In view of its biological and pathological significance, inhibition of ASK1 with small molecules has been pursued as an attractive strategy to combat human diseases such as non-alcoholic steatohepatitis (NASH). Despite several ASK1 inhibitors being developed, the failure in Phase 3 clinical trials of most advanced candidate selonsertib's, underscores to discover therapeutic agents with diverse chemical moiety. Here, by using structural pharmacophore and enumeration strategy on mining co-crystals of ASK1, different scaffolds were generated to enhance the chemical diversity keeping the critical molecular interaction in the catalytic site intact. A total of 15,772 compounds were generated from diverse chemical scaffolds and were evaluated using a virtual screening pipeline. Based on docking and MM-GBSA scores, a lead candidate, S3C-1-D424 was identified from top hits. A comparative molecular dynamics simulations (MD) of APO, Selonsertib and shortlisted potential candidates combined with pharmacokinetics profiling and thermodynamic analysis, demonstrating their suitability as potential ASK1 inhibitors to explore further for establishment towards hit-to-lead campaign.Communicated by Ramaswamy H. Sarma.

In situ modification of glycans requires extraordinary molecular recognition of highly complex and subtly different carbohydrates, followed by reactions at precise locations on the substrate. We here report synthetic catalysts that under physiological conditions cleave a predetermined oligosaccharide block such as a branched trimannose or the entire N -glycan of a glycoprotein, while nontargeted glycoproteins stay intact. The method also allows α2-6-sialylated galactosides to be removed preferentially over the α2-3-linked ones from cell surfaces, highlighting the potential of these synthetic glycosidases for glycan editing.

Background: Metachromatic leukodystrophy (MLD) is a rare lysosomal storage disorder caused by a deficiency of Arylsulfatase A (ARSA) enzyme activity. Its clinical manifestations include progressive motor and cognitive decline. ARSA gene mutations are frequent in MLD., Methods and Results: In the present study, whole exome sequencing (WES) was employed to decipher the genetic cause of motor and cognitive decline in proband's of two consanguineous families from J&K (India). Clinical investigations using radiological and biochemical analysis revealed MLD-like features. WES confirmed a pathogenic variant in the ARSA gene. Molecular simulation dynamics was applied for structural characterization of the variant., Conclusion: We report the identification of a pathogenic missense variant (c.1174 C > T; p.Arg390Trp) in the ARSA gene in two cases of late infantile MLD from consanguineous families in Jammu and Kashmir, India. Our study utilized genetic analysis and molecular dynamics simulations to identify and investigate the structural consequences of this mutation. The molecular dynamics simulations revealed significant alterations in the structural dynamics, residue interactions, and stability of the ARSA protein harbouring the p.Arg390Trp mutation. These findings provide valuable insights into the molecular mechanisms underlying the pathogenicity of this variant in MLD., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Multiple processes exist in a cell to ensure continuous production of essential proteins either through cap-dependent or cap-independent translation processes. Viruses depend on the host translation machinery for viral protein synthesis. Therefore, viruses have evolved clever strategies to use the host translation machinery. Earlier studies have shown that genotype 1 hepatitis E virus (g1-HEV) uses both cap-dependent and cap-independent translation machineries for its translation and proliferation. Cap-independent translation in g1-HEV is driven by an 87-nucleotide-long RNA element that acts as a noncanonical, internal ribosome entry site-like (IRESl) element. Here, we have identified the RNA-protein interactome of the HEV IRESl element and characterized the functional significance of some of its components. Our study identifies the association of HEV IRESl with several host ribosomal proteins, demonstrates indispensable roles of ribosomal protein RPL5 and DHX9 (RNA helicase A) in mediating HEV IRESl activity, and establishes the latter as a bona fide internal translation initiation site. IMPORTANCE Protein synthesis is a fundamental process for survival and proliferation of all living organisms. The majority of cellular proteins are produced through cap-dependent translation. Cells also use a variety of cap-independent translation processes to synthesize essential proteins during stress. Viruses depend on the host cell translation machinery to synthesize their own proteins. Hepatitis E virus (HEV) is a major cause of hepatitis worldwide and has a capped positive-strand RNA genome. Viral nonstructural and structural proteins are synthesized through a cap-dependent translation process. An earlier study from our laboratory reported the presence of a fourth open reading frame (ORF) in genotype 1 HEV, which produces the ORF4 protein using a cap-independent internal ribosome entry site-like (IRESl) element. In the current study, we identified the host proteins that associate with the HEV-IRESl RNA and generated the RNA-protein interactome. Through a variety of experimental approaches, our data prove that HEV-IRESl is a bona fide internal translation initiation site., Competing Interests: The authors declare no conflict of interest.

Introduction: Oral health is often viewed as a significant component for an indication of good general health or for good well-being together with a decent quality of life. Health literacy is considered a crucial factor in improvising a good life or excellent health. Oral health literacy (OHL) is the ability necessary for people to identify the factors that lead to poor oral health, learn and put into practice the essentials of effective oral self-care behaviors, and communicate with oral healthcare professionals in order to schedule appointments, put their names on waiting lists for dental care, and locate the dentist's office., Aim and Objectives: To evaluate students' oral health, their OHL, to determine the relationship between their oral health status and OHL, and finally to suggest preventive measures for the benefit of public health., Materials and Method: At Teerthanker Mahaveer University, a cross-sectional study involving 1500 participants, ages 18 to 25, was conducted on students studying nursing, physiotherapy, paramedicine, engineering, and law. Their informed consent was obtained. The Rapid Estimate of Adult Literacy in Dentistry (REALD-99) was used to gauge OHL levels, and the WHO's 1997 Oral Health Survey was used for their clinical evaluation., Results: The mean REALD score was significantly higher in nursing students (88.32±6.46), followed by physiotherapy college (82.46±9.11), paramedical college (70.54±10.95), law college (46.52±7.74), and least in engineering college (38.80±10.65). The difference in the REALD score based on college was statistically significant. Along with this, the REALD score showed a correlation with gender and location too. Except for fluorosis, all the clinical parameters of dental caries, gingival bleeding, and pockets, loss of attachment, dental fluorosis, and dental enamel were associated with OHL., Conclusion: The results of the current study showed a relationship between educational attainment, clinical parameters examined, and OHL, leading to the conclusion that higher OHL is related to better oral health. So, we can conclude that maintaining good oral health requires OHL., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Agarahari et al.)

To imbibe the aim of synthesizing water-soluble and biocompatible motif, a click-inspired piperazine glycoconjugate has been devised up. In this report, we present a focused approach to design and synthesis of versatile sugar-appended triazoles through 'Click Chemistry' along with their pharmacological studies on cyclin-dependent kinases (CDKs) and cell cytotoxicity on cancer cells using in silico and in vitro approaches, respectively. The study has inclusively recognized the galactose- and mannose-derived piperazine conjugates as the promising motifs. The findings suggested that the galactosyl bis-triazolyl piperazine analogue 10b is the most CDK interactive derivative and also possess significant anticancer activity., Competing Interests: Declaration of competing interest The authors declare no competing financial interests or personal relationship that could have appeared to influence the work reported in this manuscript (Ms. No.: CARB-D-23-00017-R1). In summary, the authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Mutations in homodimeric isocitrate dehydrogenase (IDH) enzymes at specific arginine residues result in the abnormal activity to overproduce D -2 hydroxyglutarate ( D -2HG), which is often projected as solid oncometabolite in cancers and other disorders. As a result, depicting the potential inhibitor for D -2HG formation in mutant IDH enzymes is a challenging task in cancer research. The mutation in the cytosolic IDH1 enzyme at R132H, especially, may be associated with higher frequency of all types of cancers. So, the present work specifically focuses on the design and screening of allosteric site binders to the cytosolic mutant IDH1 enzyme. The 62 reported drug molecules were screened along with biological activity to identify the small molecular inhibitors using computer-aided drug design strategies. The designed molecules proposed in this work show better binding affinity, biological activity, bioavailability, and potency toward the inhibition of D -2HG formation compare to the reported drugs in the in silico approach.

Interface mimicry, achieved by recognition of host-pathogen interactions, is the basis by which pathogen proteins can hijack the host machinery. The envelope (E) protein of SARS-CoV-2 is reported to mimic the histones at the BRD4 surface via establishing the structural mimicry; however, the underlying mechanism of E protein mimicking the histones is still elusive. To explore the mimics at dynamic and structural residual network level an extensive docking, and MD simulations were carried out in a comparative manner between complexes of H3-, H4-, E-, and apo-BRD4. We identified that E peptide is able to attain an 'interaction network mimicry', as its acetylated lysine (Kac) achieves orientation and residual fingerprint similar to histones, including water-mediated interactions for both the Kac positions. We identified Y59 of E, playing an anchor role to escort lysine positioning inside the binding site. Furthermore, the binding site analysis confirms that E peptide needs a higher volume, similar to the H4-BRD4 where both the lysine's (Kac5 and Kac8) can accommodate nicely, however, the position of Kac8 is mimicked by two additional water molecules other than four water-mediated bridging's, strengthening the possibility that E peptide could hijack host BRD4 surface. These molecular insights seem pivotal for mechanistic understanding and BRD4-specific therapeutic intervention. KEY POINTSMolecular mimicry is reported in hijacking and then outcompeting the host counterparts so that pathogens can rewire their cellular function by overcoming the host defense mechanism.The molecular recognition process is the basis of molecular mimicry. The E peptide of SARS-CoV-2 is reported to mimic host histone at the BRD4 surface by utilizing its C-terminally placed acetylated lysine (K ac 63) to mimic the N-terminally placed acetylated lysine K ac 5GGK ac 8 histone (H4) by interaction network mimicry identified through microsecond molecular dynamics (MD) simulations and post-processing extensive analysis.There are two steps to mimic: firstly, tyrosine residues help E to anchor at the BRD4 surface to position K ac and increase the volume of the pocket. Secondary, after positioning of K ac, a common durable interaction network N140:K ac 5; K ac 5:W1; W1:Y97; W1:W2; W2:W3; W3:W4; W4:P82 is established between K ac 5, with key residues P82, Y97, N140, and four water molecules through water mediate bridge. Furthermore, the second acetylated lysine K ac 8 position and its interaction as polar contact with K ac 5 were also mimicked by E peptide through interaction network P82:W5; W5:K ac 63; W5:W6; W6:K ac 63.The binding event at BRD4/BD1 seems an induced-fit mechanism as a bigger binding site volume was identified at H4-BRD4 on which E peptide attains its better stability than H3-BRD4.We identified the tyrosine residue Y59 of E that acts like an anchor on the BRD4 surface to position K ac inside the pocket and attain the interaction network by using aromatic residues of the BRD4 surface.Communicated by Ramaswamy H. Sarma.

The complexity and duration of tuberculosis (TB) treatment contributes to the emergence of drug resistant tuberculosis (DR-TB) and drug-associated side effects. Alternate chemotherapeutic agents are needed to shorten the time and improve efficacy of current treatment. In this study, we have assessed the antitubercular activity of NSC19723, a benzaldehyde thiosemicarbazone molecule. NSC19723 is structurally similar to thiacetazone (TAC), a second-line anti-TB drug used to treat individuals with DR-TB. NSC19723 displayed better MIC values than TAC against Mycobacterium tuberculosis and Mycobacterium bovis BCG. In our checkerboard experiments, NSC19723 displayed better profiles than TAC in combination with known first-line and recently approved drugs. Mechanistic studies revealed that NSC19723 inhibits mycolic acid biosynthesis by targeting the HadABC complex. Computational studies revealed that the binding pocket of HadAB is similarly occupied by NSC19723 and TAC. NSC19723 also improved the efficacy of isoniazid in macrophages and mouse models of infection. Cumulatively, we have identified a benzaldehyde thiosemicarbazone scaffold that improved the activity of TB drugs in liquid cultures, macrophages, and mice. IMPORTANCE Mycobacterium tuberculosis, the causative agent of TB is among the leading causes of death among infectious diseases in humans. This situation has worsened due to the failure of BCG vaccines and the increased number of cases with HIV-TB coinfections and drug-resistant strains. Another challenge in the field is the lengthy duration of therapy for drug-sensitive and -resistant TB. Here, we have deciphered the mechanism of action of NSC19723, benzaldehyde thiosemicarbazone. We show that NSC19723 targets HadABC complex and inhibits mycolic acid biosynthesis. We also show that NSC19723 enhances the activity of known drugs in liquid cultures, macrophages, and mice. We have also performed molecular docking studies to identify the interacting residues of HadAB with NSC19723. Taken together, we demonstrate that NSC19723, a benzaldehyde thiosemicarbazone, has better antitubercular activity than thiacetazone.

The ability to predict the intricate mechanistic behavior of ligands and associated structural determinants during protein-ligand (un)binding is of great practical importance in drug discovery. Ubiquitin specific protease-7 (USP7) is a newly emerging attractive cancer therapeutic target with bound allosteric inhibitors. However, none of the inhibitors have reached clinical trials, allowing opportunities to examine every aspect of allosteric modulation. The crystallographic insights reveal that these inhibitors have common properties such as chemical scaffolds, binding site and interaction fingerprinting. However, they still possess a broader range of binding potencies, ranging from 22 nM to 1,300 nM. Hence, it becomes more critical to decipher the structural determinants guiding the enhanced binding potency of the inhibitors. In this regard, we elucidated the atomic-level insights from both interacting partners, that is, protein-ligand perspective, and established the structure-activity link between USP7 inhibitors by using classical and advanced molecular dynamics simulations combined with linear interaction energy and molecular mechanics-Poisson Boltzmann surface area. We revealed the inhibitor potency differences by examining the contributions of chemical moieties and USP7 residues, the involvement of water-mediated interactions, and the thermodynamic landscape alterations. Additionally, the dissociation profiles aided in the establishment of a correlation between experimental potencies and structural determinants. Our study demonstrates the critical role of blocking loop 1 in allosteric inhibition and enhanced binding affinity. Comprehensively, our findings provide a constructive expansion of experimental outcomes and show the basis for varying binding potency using in-silico approaches. We expect this atomistic approach to be useful for effective drug design., (© 2022 The Protein Society.)

Tuberculosis, a disease of poverty is a communicable infection with a reasonably high mortality rate worldwide. 10 Million new cases of TB were reported with approx 1.4 million deaths in the year 2019. Due to the growing number of drug-sensitive and drug-resistant tuberculosis cases, there is a vital need to develop new and effective candidates useful to combat this deadly disease. Despite tremendous efforts to identify a mechanism-based novel antitubercular agent, only a few have entered into clinical trials in the last six decades. In recent years, triazoles have been well explored as the most valuable scaffolds in drug discovery and development. Triazole framework possesses favorable properties like hydrogen bonding, moderate dipole moment, enhanced water solubility, and also the ability to bind effectively with biomolecular targets of M. tuberculosis and therefore this scaffold displayed excellent potency against TB. This review is an endeavor to summarize an up-to-date innovation of triazole-appended hybrids during the last 10 years having potential in vitro and in vivo antitubercular activity with structure activity relationship analysis. This review may help medicinal chemists to explore the triazole scaffolds for the rational design of potent drug candidates having better efficacy, improved selectivity and minimal toxicity so that these hybrid NCEs can effectively be explored as potential lead to fight against M. tuberculosis., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

Protein seldom performs biological activities in isolation. Understanding the protein-protein interactions' physical rewiring in response to pathological conditions or pathogen infection can help advance our comprehension of disease etiology, progression, and pathogenesis, which allow us to explore the alternate route to control the regulation of key target interactions, timely and effectively. Nonalcoholic steatohepatitis (NASH) is now a global public health problem exacerbated due to the lack of appropriate treatments. The most advanced anti-NASH lead compound (selonsertib) is withdrawn, though it is able to inhibit its target Apoptosis signal-regulating kinase 1 (ASK1) completely, indicating the necessity to explore alternate routes rather than complete inhibition. Understanding the interaction fingerprints of endogenous regulators at the molecular level that underpin disease formation and progression may spur the rationale of designing therapeutic strategies. Based on our analysis and thorough literature survey of the various key regulators and PTMs, the current review emphasizes PPI-based drug discovery's relevance for NASH conditions. The lack of structural detail (interface sites) of ASK1 and its regulators makes it challenging to characterize the PPI interfaces. This review summarizes key regulators interaction fingerprinting of ASK1, which can be explored further to restore the homeostasis from its hyperactive states for therapeutics intervention against NASH., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier B.V. on behalf of Research Network of Computational and Structural Biotechnology.)

The COVID-19 pandemic caused by SARS-CoV-2 has a significant burden on the economy and healthcare around the world. Vaccines are the most effective tools to fight infectious diseases by containing the spread of the disease. The current vaccines against SARS-CoV-2 are mostly based on the spike protein of SARS-CoV-2, which is large and has many immune-dominant non-neutralizing epitopes that may effectively skew the antibody response towards non-neutralizing antibodies. Here, we have explored the possibility of immune-focusing the receptor binding motif (RBM) of the spike protein of SARS-CoV-2 that induces mostly neutralizing antibodies in natural infection or in vacinees. The result shows that the scaffolded RBM can bind to Angiotensin Converting Enzyme 2 (ACE2) although with low affinity and induces a strong antibody response in mice. The immunized sera can bind both, the receptor binding domain (RBD) and the spike protein, which holds the RBM in its natural context. Sera from the immunized mice showed robust interferon γ response but poor neutralization of SARS-CoV-2 suggesting presence of a predominant T cell epitope on scaffolded RBM. Together, we provide a strategy for inducing strong antigenic T cell response which could be exploited further for future vaccine designing and development against SARS-CoV-2 infection., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In the last few years, technological advancement has led to the use of wearable body sensors for gathering patient information. Wireless body area networks played an essential role in the modern medical era. Through wearable body sensors, patient data are sent to medical professionals in real-time without any hindrance. This information moves through the public channel, and thus proper security and protection are needed because of its sensitiveness. Many authentication protocols proposed for solving these issues were neither secure nor cost-effective. This paper proposed an authentication protocol using certificateless cryptography for wireless body area networks to resolve the associated security concerns. A formal security analysis is done using the Burrows-Abadi-Needham logic shows that the proposed protocol is resilient against prevailing attacks. Additionally, we employ the Real-or-Random model for mathematical proof and Automated Verification Security Protocol and Analysis simulation tool for security analysis. A detailed comprehensive comparison with the existing protocols indicates that the proposed protocol is cost-effective with improved functionality., (© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022.)

Glycosyl triazoles have been introduced as efficient ligands for the Cu-catalyzed Sonogashira reaction to overcome the challenges of sideways homocoupling reactions in Cu catalysis in this reaction. The atmospheric oxygen in a sealed tube did not affect the coupling, and no need of complete exclusion of oxygen was experienced in the presence of glycohybrid triazole ligand L3. High product yields were obtained at 130 °C for a variety of substrates including aliphatic and aromatic terminal alkynes and differently substituted aromatic halides including 9-bromo noscapine. In contrast, at room temperature, a very low loading of the L3- Cu catalytic system could produce excellent yields in Glaser coupling including homocoupling and heterocoupling of a variety of aliphatic and aromatic alkynes.

Glycodendrimers are receiving considerable attention to mimic a number of imperative features of cell surface glycoconjugate and acquired excellent relevance to a wide domain of investigations including medicine, pharmaceutics, catalysis, nanotechnology, carbohydrate-protein interaction, and moreover in drug delivery systems. Toward this end, an expeditious, modular, and regioselective triazole-forming CuAAC click approach along with double stage convergent synthetic method was chosen to develop a variety of novel chlorine-containing cyclen cored glycodendrimers of high sugar tethers at low generation of promising therapeutic potential. We developed a novel chlorine-containing hypercore unit with 12 alkynyl functionality originated from cyclen scaffold which was confirmed by its single crystal X-ray data analysis. Further, the modular CuAAC technique was utilized to produce a variety of novel 12-sugar coated (G 0 ) glycodendrimers 12-15 adorn with β-Glc-, β-Man-, β-Gal-, β-Lac, along with 36-galactose coated (G 1 ) glycodendrimer 18 in good-to-high yield. The structures of the developed glycodendrimer architectures have been well elucidated by extensive spectral analysis including NMR ( 1 H & 13 CNMR), HRMS, MALDI-TOF MS, UV-Vis, IR, and SEC (Size Exclusion Chromatogram) data., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

d-Glucosamine, a natural, inexpensive, and conveniently accessible sugar, has been explored as an efficient ligand for the Cu(I)-catalyzed regio- and stereoselective synthesis of an array of ( Z )-3-methyleneisoindoline-1-ones and ( E )- N -aryl-4 H -thiochromen-4-imines in good-to-excellent yield in a tandem fashion via the reaction of 2-halobenzamide and 2-halobenzothioamide with terminal alkynes, respectively. The water solubility and biocompatible nature of the ligand offer easy separation of the catalytic system toward the aqueous phase as well as change in the reaction path in terms of the product also demonstrated the variation of the reaction temperature. The domino reaction proceeds by the Sonogashira and Ullmann type cross-coupling reaction, followed by Cu(I)-promoted additive cyclization of heteroatom to the triple bond. In addition, d-glucosamine causes successful Glaser-Hay coupling of terminal alkynes under Cu catalysis to produce a high yield of respective 1,3-diynes., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Copper(I)-catalyzed 1,3-dipolar cycloaddition between organic azides and terminal alkynes, commonly known as CuAAC or click chemistry, has been identified as one of the most successful, versatile, reliable, and modular strategies for the rapid and regioselective construction of 1,4-disubstituted 1,2,3-triazoles as diversely functionalized molecules. Carbohydrates, an integral part of living cells, have several fascinating features, including their structural diversity, biocompatibility, bioavailability, hydrophilicity, and superior ADME properties with minimal toxicity, which support increased demand to explore them as versatile scaffolds for easy access to diverse glycohybrids and well-defined glycoconjugates for complete chemical, biochemical, and pharmacological investigations. This review highlights the successful development of CuAAC or click chemistry in emerging areas of glycoscience, including the synthesis of triazole appended carbohydrate-containing molecular architectures (mainly glycohybrids, glycoconjugates, glycopolymers, glycopeptides, glycoproteins, glycolipids, glycoclusters, and glycodendrimers through regioselective triazole forming modular and bio-orthogonal coupling protocols). It discusses the widespread applications of these glycoproducts as enzyme inhibitors in drug discovery and development, sensing, gelation, chelation, glycosylation, and catalysis. This review also covers the impact of click chemistry and provides future perspectives on its role in various emerging disciplines of science and technology.

In over eighty years, despite successive antibiotics discoveries, the rapid advent of multidrug resistance among bacterial pathogens has jolted our misapprehension of success over them. Resistance is spreading faster than the discovery of new antibiotics/antimicrobials. Therefore, the search for better antimicrobials/additives becomes prudent. A water-soluble curcumin derivative (Cur aq ) was synthesised, employing a Cu (I) catalysed 1, 3-cyclo addition reaction; it has been evaluated as a potential treatment for multidrug-resistant isolates and as an antibiotic adjuvant for meropenem against hypervirulent multidrug-resistant Klebsiella pneumoniae isolates. We also investigated its solubility and effect over carbapenemase activity. Additionally, we investigated its impact on the AcrAB-TolC system. We found that Cur aq inhibited bacterial growth at a minimal concentration of 16 µg/mL; at a 32 µg/mL concentration, it killed bacterial growth completely. Only nine (9.4%) Klebsiella isolates were sensitive to meropenem; however, after synergising with Cur aq (8 µg/mL), 85 (88.54%) hvKP isolates became sensitive to the drug. The Cur aq also inhibited the AcrAB-TolC efflux system at 1 µg/mL concentration by disrupting the membrane potential and causing depolarisation. The kinetic parameters obtained also indicated its promise as a carbapenemase inhibitor. These results suggest that Cur aq can be an excellent drug candidate as a broad-spectrum antibacterial and anti-efflux agent.

The upsurge of multidrug resistant bacterial infections with declining pipeline of newer antibiotics has made it imperative to develop newer molecules or tailor the existing molecules for more effective antimicrobial therapies. Since antiquity, the use of curcumin, in the form of Curcuma longa paste, to treat infectious lesions is unperturbed despite its grave limitations like instability and aqueous insolubility. Here, we utilized "click" chemistry to address both the issues along with improvisation of its antibacterial and antibiofilm profile. We show that soluble curcumin disrupts several bacterial cellular processes leading to the Fenton's chemistry mediated increased production of reactive oxygen species and increased membrane permeability of both Gram-positive and Gram-negative bacteria. We here report that its ability to induce oxidative stress can be harnessed to potentiate activities of ciprofloxacin, meropenem, and vancomycin. In addition, we demonstrated that the soluble curcumin reported herein even sensitizes resistant Gram-negative clinical isolates to the Gram-positive specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. This work shows that the soluble curcumin can be used to enhance the action of existing antimicrobials against both Gram-positive and Gram-negative bacteria thus strengthening the antibiotic arsenal for fighting resistant bacterial infections for many years to come.

The primary motive behind this article is to bring to the forefront a unique kind of dendrimer which has remained a dark horse since its discovery, namely dentromer. We herein report the synthesis of glycodendrimers and glycodentromers crowned with galactose units by harnessing an expeditious synthesis of dendrimer core 18 and dentromer core 19, divergently with branching directionality (1 → 2) and (1 → 3), respectively. A competent, double stage convergent synthetic path was chosen to facilitate ease of refining and spectroscopic elucidations. By exploiting a Cu(i)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction strategy, we successfully developed a new series of galactosylated dendrimers 20, 21, 22, and 24 containing 6, 12, 18, and 18 peripheral galactose units, respectively. We are first to report the practical synthesis of 9-peripheral galactose coated glycodentromer 23 (0 th generation) and 27-peripheral galactose coated glycodentromer 25 (1 st generation). These synthesized scaffolds were characterized by spectral studies such as 1 H, 13 C NMR, FT-IR, MALDI-TOF MS, HRMS and SEC analysis. Additionally, gel permeation chromatography depicted the regular progression in size from 6 to 27-peripheral galactose coated glycodendrimers along with glycodentromers, with their high monodispersity. Also, the glyco-dendrimers and dentromers synthesized from two different hypercore units i.e. dendrimers core (18) and dentromer core (19), have been supported by their UV-visible absorbance and emission spectroscopy., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Among all the malaria parasites, P. falciparum is the most predominant species which has developed drug resistance against most of the commercial anti-malarial drugs. Thus, finding a new molecule for the inhibition of enzymes of P. falciparum is the pharmacological challenge in present era. Herein, ten novel molecules have been designed with an amalgamation of cinchonidine, carbohydrate moiety and triazole ring by utilizing copper-catalyzed click reaction of cinchonidine-derived azide and clickable glycosyl alkynes. The molecular docking of developed molecules showed promising results for plasmepsin inhibition in the form of effective binding with target proteins.

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal blood disorder that manifests with hemolytic anemia, thrombosis, and peripheral blood cytopenias. The disease is caused by the deficiency of two glycosylphosphatidylinositols (GPI)-anchored proteins (CD55 and CD59) in the hemopoietic stem cells. The deficiency of GPI-anchored proteins has been associated with the somatic mutations in phosphatidylinositol glycan class A ( PIGA ). However, the mutations that do not cause PNH is associated with the multiple congenital anomalies-hypotonia-seizures syndrome 2 (MCAHS2). To best of our knowledge, no computational study has been performed to explore at an atomistic level the impact of PIGA missense mutations on the structure and dynamics of the protein. Therefore, we focused our study to provide molecular insights into the changes in protein structural dynamics upon mutation. In the initial step, screening for the most pathogenic mutations from the pool of publicly available mutations was performed. Further, to get a better understanding, pathogenic mutations were mapped to the modeled structure and the resulting protein was subjected to 100 ns molecular dynamics simulation. The residues close to C- and N-terminal regions of the protein were found to exhibit greater flexibility upon mutation. Our study suggests that four mutations are highly effective in altering the structural conformation and stability of the PIGA protein. Among them, mutant G48D was found to alter protein's structural dynamics to the greatest extent, both on a local and a global scale., (© 2019 The Authors. Published by Elsevier Ltd.)

The aim of this analytical study was to assess the reduction in intra- and post-operative complications of parotid surgeries for benign lesions following simple surgical steps and to compare the outcome with the literature. A retrospective study of 77 patients requiring parotidectomy surgery for benign parotid lesions was conducted in Department of Otorhinolaryngology, Sri Guru Ram Rai Institute of Medical and Health Sciences, Dehradun from the period of January 2011 to January 2016. Patients were followed up for 1-5 years and serial evaluation was done for all cases who developed any of intra- or post-operative complications in their disease course. The ages of presentation varied from 1.5 to 70 years. There were 51 males and 26 female patients. Majority cases were of pleomorphic adenoma followed by warthins tumor. Superficial parotidectomy was done in 69 patients; 4 cases required near total parotidectomy while total conservative parotidectomy was done in 4 cases. The commonest complication was altered sensations around the ear which was seen in 10 cases followed by temporary facial nerve paresis and sialocele formation which occurred in 3 cases each. This study advocates the importance of detailed anatomical knowledge, behavior of various benign pathologies, experience of surgeon and his fine dissection techniques to ensure minimum risks of injury to important structures in surgical field., (© Association of Otolaryngologists of India 2018.)

Neutrophils play important role in immunity and inflammation through diverse mechanisms. Reports from this lab and others have demonstrated involvement of NO in neutrophil adhesion, chemotaxis, bacterial killing, reactive oxygen species generation, neutrophil extracellular traps' formation, and apoptosis. Constitutive expression of iNOS in human neutrophils has also been documented. The role of NO-iNOS in neutrophil differentiation however remains ill-defined. The present study was undertaken to understand the role of NO generated from iNOS in the neutrophil differentiation by using iNOS-overexpressing K562 cells (K562 iNOS ) and iNOS-deficient murine progenitor cells (lineage negative cells; lin -ve ). We observed that iNOS overexpression led to increased neutrophilic differentiation in K562 cells; more specifically an early and accelerated neutrophilic differentiation was spotted in K562 iNOS . These observations were further validated using iNOS knockout lin -ve cells or hematopoietic progenitor cells that exhibited delayed neutrophil differentiation in comparison to its wild-type counterpart. In addition, a significant increase in the gene expression of iNOS during neutrophilic differentiation of CD34 + hematopoietic stem and progenitor cells derived from human bone marrow further substantiates importance of iNOS in neutrophil differentiation. Moreover, a significant increase in NO generation during neutrophil differentiation was observed and enhanced neutrophil differentiation with NO donor was also observed, implying the importance of NO in neutrophil differentiation. Collectively, using alternative approaches, we demonstrated that neutrophil differentiation is significantly influenced by iNOS or NO, suggesting the possibility of exploiting this novel link for therapeutic aspects of NO generated from iNOS and neutrophil differentiation in hematopoiesis-related disorders., (©2019 Society for Leukocyte Biology.)

Background: Complete lesion after spinal cord injury (SCI) remains irreversible with little hope of neurological recovery. Newer interventions such as re-stimulation of damaged neurons using artificial agents and the use of stem cells for neuronal regeneration have shown promising results., Aim: This study was undertaken for evaluating the neurological status of acute SCI participants after stem cell augmentation and comparing them with other treatment methods., Setting and Design: Randomized controlled trial in the northern Indian population., Materials and Methods: A total 193 SCI participants of complete paraplegia with unstable T4-L2 injury having thoracolumbar injury severity score ≥4 were enrolled in this study. Participants were randomly allocated for three different treatment modalities, namely, conventional with stem cell augmentation (Group-1), conventional (Group-2), and conservative (Group-3). Neurological recovery after 1 year was evaluated through the ASIA Impairment Scale (AIS)-grading, sensory, and motor scores., Statistical Analysis: T -test for sensory-motor score analysis of each group and analysis of variance for comparison of same variables between the groups., Results: After 1-year significant difference was observed in the AIS-grade, sensory and motor scores in-Group 1 ( P < 0.001). In Group-1 versus 2, the mean difference at 1 year for AIS grade, sensory and motor scores were 0.40 ( P = 0.010, 95% confidence interval [CI] 0.075-0.727), 8.52 ( P = 0.030, 95% CI 0.619-16.419), and 4.55( P = 0.003, 95% CI 1.282-7.815), respectively. In Group-1 versus 3, 1.03, 19.02 and 7.22 ( P < 0.001 for each of the parameters) and in Group-2 versus 3, 0.63 ( P < 0.001), 10.49 ( P = 0.009), and 2.68 ( P = 0.019), respectively., Conclusions: Significant motor neurological recovery and AIS-grade promotion was observed in Group-1 as compared to Group-2 and 3., Competing Interests: There are no conflicts of interest., (Copyright: © 2019 Asian Journal of Transfusion Science.)

The G2019S substitution in the Leucine-rich repeat kinase 2 (LRRK2) is significantly associated with Parkinson's disease (PD). This substitution was identified in both familial and sporadic forms of PD with a higher frequency. Few computational studies have reported the impact of G2019S substitution on inhibitors of the kinase domain of LRRK2. However, no computational study deeply investigated the possible impact of the G2019S substitution on the kinase domain in its Apo conformation. Therefore, in this study, we used 200 ns molecular dynamic simulation using the GROMACS 5.1.4 package software to investigate the impact of the G2019S substitution on the structure of the kinase domain of LRRK2. Our results indicate that the G2019S substitution affects the dynamics and stability of LRRK2 by decreasing the flexibility and increasing the compactness of the kinase domain and showing its tendency to be in an active conformation for long time interval because of the high energy barrier between active and inactive conformation. This study predicts the molecular pathogenicity mechanism of the G2019S on patients with PD and provides a potential platform for developing therapeutics for patients with PD that harbor this amino acid substitution., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Glycosyl triazoles are conveniently accessible and contain multiple metal-binding units that may assist in metal-mediated catalysis. Azide derivatives of d-glucose have been converted to their respective aryltriazoles and screened as ligands for the synthesis of 2-substituted benz-fused azoles and benzimidazoquinazolinones by Cu-catalyzed intramolecular Ullmann type C-heteroatom coupling. Good to excellent yields for a variety of benz-fused heterocyles were obtained for this readily accessible catalytic system.

A green modification has been introduced to the synthesis of benzothiazoles by using polymethylhydrosiloxane (PMHS) for successive steps of benzotriazole ring cleavage and cyclization, an approach which was previously developed in our lab by the use of n -Bu 3 SnH. The use of the silicone industry byproduct PMHS makes this protocol a cost-effective and nontoxic one and thus may be considered for the industrial importance., Competing Interests: The authors declare no competing financial interest.

The nucleotide salvage pathway is used to recycle degraded nucleotides (purines and pyrimidines); one of the enzymes that helps to recycle purines is hypoxanthine guanine phosphoribosyl transferase 1 (HGPRT1). Therefore, defects in this enzyme lead to the accumulation of DNA and nucleotide lesions and hence replication errors and genetic disorders. Missense mutations in hypoxanthine phosphoribosyl transferase 1 (HPRT1) are associated with deficiencies such as Lesch-Nyhan disease and chronic gout, which have manifestations such as arthritis, neurodegeneration, and cognitive disorders. In the present study, we collected 88 non-synonymous single nucleotide polymorphisms (nsSNPs) from the UniProt, dbSNP, ExAC, and ClinVar databases. We used a series of sequence-based and structure-based in silico tools to prioritize and characterize the most pathogenic and stabilizing or destabilizing nsSNPs. Moreover, to obtain the structural impact of the pathogenic mutations, we mapped the mutations to the crystal structure of the HPRT protein. We further subjected these mutant proteins to a 50 ns molecular dynamics simulation (MDS). The MDS trajectory showed that all mutant proteins altered the structural conformation and dynamic behavior of the HPRT protein and corroborated its association with LND and gout. This study provides essential information regarding the use of HPRT protein mutants as potential targets for therapeutic development., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Benzotriazole has been established as an efficient ligand in Cu-catalyzed cross-coupling of terminal alkynes to form 1,3-dialkynes using CuI as the catalyst and K 2 CO 3 as the base at room temperature in an open round-bottom flask. The established protocol has the following notable advantages: simple to handle, easy work-up, mild reaction condition, high substrate scope, requirement of less quantity of ligand and also Cu-catalyst, less expensive, and high reaction yield., Competing Interests: The authors declare no competing financial interest.

The NF1 gene encodes for neurofibromin protein, which is ubiquitously expressed, but most highly in the central nervous system. Non-synonymous SNPs (nsSNPs) in the NF1 gene were found to be associated with Neurofibromatosis Type 1 disease, which is characterized by the growth of tumors along nerves in the skin, brain, and other parts of the body. In this study, we used several in silico predictions tools to analyze 16 nsSNPs in the RAS-GAP domain of neurofibromin, the K1444N (K1423N) mutation was predicted as the most pathogenic. The comparative molecular dynamic simulation (MDS; 50 ns) between the wild type and the K1444N (K1423N) mutant suggested a significant change in the electrostatic potential. In addition, the RMSD, RMSF, Rg, hydrogen bonds, and PCA analysis confirmed the loss of flexibility and increase in compactness of the mutant protein. Further, SASA analysis revealed exchange between hydrophobic and hydrophilic residues from the core of the RAS-GAP domain to the surface of the mutant domain, consistent with the secondary structure analysis that showed significant alteration in the mutant protein conformation. Our data concludes that the K1444N (K1423N) mutant lead to increasing the rigidity and compactness of the protein. This study provides evidence of the benefits of the computational tools in predicting the pathogenicity of genetic mutations and suggests the application of MDS and different in silico prediction tools for variant assessment and classification in genetic clinics.

Charcot-Marie-Tooth disease (CMT) is one of the most commonly inherited congenital neurological disorders, affecting approximately 1 in 2500 in the US. About 80 genes were found to be in association with CMT. The phosphoribosyl pyrophosphate synthetase 1 (PRPS1) is an essential enzyme in the primary stage of de novo and salvage nucleotide synthesis. The mutations in the PRPS1 gene leads to X-linked Charcot-Marie-Tooth neuropathy type 5 (CMTX5), PRS super activity, Arts syndrome, X-linked deafness-1, breast cancer, and colorectal cancer. In the present study, we obtained 20 missense mutations from UniProt and dbSNP databases and applied series of comprehensive in silico prediction methods to assess the degree of pathogenicity and stability. In silico tools predicted four missense mutations (D52H, M115 T, L152P, and D203H) to be potential disease causing mutations. We further subjected the four mutations along with native protein to 50 ns molecular dynamics simulation (MDS) using Gromacs package. The resulting trajectory files were analyzed to understand the stability differences caused by the mutations. We used the Root Mean Square Deviation (RMSD), Radius of Gyration (Rg), solvent accessibility surface area (SASA), Covariance matrix, Principal Component Analysis (PCA), Free Energy Landscape (FEL), and secondary structure analysis to assess the structural changes in the protein upon mutation. Our study suggests that the four mutations might affect the PRPS1 protein function and stability of the structure. The proposed study may serve as a platform for drug repositioning and personalized medicine for diseases that are caused by the PRPS1 deficiency.

X-linked Charcot-Marie-Tooth type 1 X (CMTX1) disease is a subtype of Charcot-Marie-Tooth (CMT), which is mainly caused by mutations in the GJB1 gene. It is also known as connexin 32 (Cx32) that leads to Schwann cell abnormalities and peripheral neuropathy. CMTX1 is considered as the second most common form of CMT disease. The aim of this study is to computationally predict the potential impact of different single amino acid substitutions at position 75 of Cx32, from arginine (R) to proline (P), glutamine (Q) and tryptophan (W). This position is known to be highly conserved among the family of connexin. To understand the structural and functional changes due to these single amino acid substitutions, we employed a homology-modeling technique to build the three-dimensional structure models for the native and mutant proteins. The protein structures were further embedded into a POPC lipid bilayer, inserted into a water box, and subjected to molecular dynamics simulation for 50 ns. Our results show that the mutants R75P, R75Q and R75W display variable structural conformation and dynamic behavior compared to the native protein. Our data proves useful in predicting the potential pathogenicity of the mutant proteins and is expected to serve as a platform for drug discovery for patients with CMT., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Mutations in the Peripheral Myelin Protein 22 (PMP22) leads to Charcot Marie Tooth type 1A (CMT1A, a subtype of CMT1) disease which is the most common inherited neuropathy of peripheral nervous system. In the present study, we used series of in silico prediction methods to screen and identify the most deleterious non-synonymous SNPs (nsSNPs) in PMP22 gene. Out of 48 nsSNPs, five nsSNPs (L16P, L19P, T23R, W28R, and L147R) associated with PMP22 were predicted to be highly deleterious and destabilizing the protein. To explore the possible structure-function relationship, we employed abinitio modeling strategy using the CABS-fold server to predict the three-dimensional structure models in the absence of crystallized structures in PMP22 protein. We used Cytoscape 3.4.0 plugin Integrated Complex Traits Networks interface (iCTNet) to identify the probable drug-gene interactions in PMP22 gene. A total of 22 chemical compounds yielded from the aforementioned tool was subjected to Molinspiration and OSIRIS program to screen and identify the potent drug molecules for further analysis. Five chemical compounds with excellent bioavailability and drug relevant property were selected for molecular docking simulation study. We modeled five mutant structures at their corresponding positions and performed molecular docking simulation analysis using AutoDock Tools (ADT) version 1.5.6 and ArgusLab 4.0.1 tools to analyze their interaction patterns and binding efficacy. Based on the results obtained from the computational study, we predict that estradiol could be a potential drug of choice for treating patients with CMT1A which needs larger attention from biologists in the near future. J. Cell. Biochem. 118: 3730-3743, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

A controlled and facile synthesis of various glycosyl 1,3-oxazolidine-2-thiones and 1,3- thiozolidine-2-thiones has been accomplished from corresponding sugar azido alcohols utilizing Staudinger reaction (PPh 3 and CS 2 ) via isothiocynate route. A series of reactions were performed to investigate the effects of CS 2 and PPh 3 on the selectivity of product formed. The excessive addition of CS 2 with PPh 3 (1.2 equiv) afforded oxazolidine-2-thione alone, while the solitary addition of PPh 3 for 30 min followed by addition of CS 2 to the reaction mixture resulted both the products in different ratios, which were successfully isolated using column chromatography (SiO 2 ). Furthermore, synthesis of 1,3-oxathiolan-2-imine from glycosyl epoxide has also been attempted. Structures of all the developed compounds have been elucidated using extensive spectroscopic techniques including IR, NMR and MS analysis., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objectives: The study aimed at finding prevalence, mode of transmission, and pattern of CD4 cell count among hepatitis C virus (HCV) coinfected human immunodeficiency virus (HIV)-positive individuals in Nepal., Methods: This was a descriptive cross-sectional study carried out in three Volunteer Counseling and Testing clinics, one from Dharan and two from Kathmandu, Nepal. Three hundred and thirteen individuals were recruited., Results: Forty-two percent of HIV-infected persons had HCV coinfection. Significant associations with HIV and HCV coinfection were male gender (p <0.001) and injection drug use (IDU) (p <0.001). The mean CD4 cell count was significantly lower in HCV coinfected individuals, compared to those without coinfection, after 1.5 years (p =0.017), 2 years (p =0.0457), 3 years (p =0.011), and 3.5 years (p <0.001) of antiretroviral therapy., Conclusion: HCV coinfection was common in HIV-infected individuals in Nepal and was associated with male gender, IDU, and lower CD4 counts.