Dual template (epitope) imprinted electrode for sensing bacterial protein with high selectivity.

Epitope imprinting has shown better prospects to synthesize synthetic receptors for proteins. Here, dual epitope imprinted polymer electrode (DEIP) matrix was fabricated on gold surface of electrochemical quartz crystal microbalance (EQCM) for recognition of target epitope sequence in blood samples of patients suffering from brain fever. Epitope sequences from outer membrane protein Por B of Neisseria meningitidis (MC58) bacteria predicted through immunoinformatic tools were chosen for imprinting. Self-assembled monolayers (SAM) of cysteine appended epitope sequences on gold nanoparticles were subjected to polymerization prior to electrodeposition on gold coated EQCM electrode. The polymeric matrix was woven around the cysteine appended epitope SAMs through multiple monomers (3-sulfo propyl methacrylate potassium salt (3-SPMAP), benzyl methacrylate (BMA)) and crosslinker (N, N'-methylene-bis-acrylamide). On extraction of the peptide sequences, imprinted cavities were able to selectively and specifically bind targeted epitope sequences in laboratory samples as well as 'real' samples of patients. Selectivity of sensor was examined through mismatched peptide sequences and certain plasma proteins also. The sensor was able to show specific binding towards the blood samples of infected patients, even in the presence of 'matrix' and other plasma proteins such as albumin and globulin. Even other peptide sequences, similar to epitope sequences only with one or two amino acid mismatches were also unable to show any binding. The analytical performance of DEIP-EQCM sensor was tested through selectivity, specificity, matrix effect, detection limit (0.68-1.01 nM), quantification limit (2.05-3.05 nM) and reproducibility (RSD ~ 5%). Hence, a diagnostic tool for bacterium causing meningitis is successfully fabricated in a facile manner which will broaden the clinical access and make efficient population screening feasible.

One-pot Synthesis of 2-Aminoindole through SET Oxidative Cyclization: Concise Synthesis of Tryptanthrin and Phaitanthrin E.

An efficient domino approach for the synthesis of biologically important 2-aminoindole derivatives has been developed using CuBr2 -mediated SET oxidative cyclization as a key step. This one-pot multicomponent strategy utilizes readily available ethyl propiolate, tosyl azide, and substituted aryl amines as starting materials. The generality and scope of this mild method are demonstrated with a wide variety of substrates to furnish functionalized 2-aminoindoles in good yields. The synthetic power of this strategy is further exemplified in the concise synthesis of biologically important alkaloids, Phaitanthrin E and Tryptanthrin.

Toxin-antitoxin systems and their medical applications: current status and future perspective.

Almost all bacteria synthesize two types of toxins-one for its survival by regulating different cellular processes and another as a strategy to interact with host cells for pathogenesis. Usually, "bacterial toxins" are contemplated as virulence factors that harm the host organism. However, toxins produced by bacteria, as a survival strategy against the host, also hamper its cellular processes. To overcome this, the bacteria have evolved with the production of a molecule, referred to as antitoxin, to negate the deleterious effect of the toxin against itself. The toxin and antitoxins are encoded by a two-component toxin-antitoxin (TA) system. The antitoxin, a protein or RNA, sequesters the toxins of the TA system for neutralization within the bacterial cell. In this review, we have described different TA systems of bacteria and their potential medical and biotechnological applications. It is of interest to note that while bacterial toxin-antitoxin systems have been well studied, the TA system in unicellular eukaryotes, though predicted by the investigators, have never been paid the desired attention. In the present review, we have also touched upon the TA system of eukaryotes identified to date. KEY POINTS: Bacterial toxins harm the host and also affect the bacterial cellular processes. The antitoxin produced by bacteria protect it from the toxin's harmful effects. The toxin-antitoxin systems can be targeted for various medical applications.

Integrative natural medicine inspired graphene nanovehicle-benzoxazine derivatives as potent therapy for cancer.

Natural products from medicinal plants have always attracted a lot of attention due to their diverse and interesting therapeutic properties. We have employed the principles of green chemistry involving isomerization, coupling and condensation reaction to synthesize a class of compounds derived from eugenol, a naturally occurring bioactive phytophenol. The compounds were characterized structurally by 1H-, 13C-NMR, FT-IR spectroscopy and mass spectrometry analysis. The purity of compounds was detected by HPLC. The synthesized compounds exhibited anti-cancer activity. A 10-12-fold enhancement in efficiency of drug molecules (~ 1 µM) was observed when delivered with graphene oxide (GO) as a nanovehicle. Our data suggest cell death via apoptosis in a dose-dependent manner due to increase in calcium levels in specific cancer cell lines. Interestingly, the benzoxazine derivatives of eugenol with GO nanoparticle exhibited enhanced therapeutic potential in cancer cells. In addition to anti-cancer effect, we also observed significant role of these derivatives on parasite suggesting its multi-pharmacological capability.

Endoplasmic Reticulum Stress Induced Synthesis of a Novel Viral Factor Mediates Efficient Replication of Genotype-1 Hepatitis E Virus.

Hepatitis E virus (HEV) causes acute hepatitis in many parts of the world including Asia, Africa and Latin America. Though self-limiting in normal individuals, it results in ~30% mortality in infected pregnant women. It has also been reported to cause acute and chronic hepatitis in organ transplant patients. Of the seven viral genotypes, genotype-1 virus infects humans and is a major public health concern in South Asian countries. Sporadic cases of genotype-3 and 4 infection in human and animals such as pigs, deer, mongeese have been reported primarily from industrialized countries. Genotype-5, 6 and 7 viruses are known to infect animals such as wild boar and camel, respectively. Genotype-3 and 4 viruses have been successfully propagated in the laboratory in mammalian cell culture. However, genotype-1 virus replicates poorly in mammalian cell culture and no other efficient model exists to study its life cycle. Here, we report that endoplasmic reticulum (ER) stress promotes genotype-1 HEV replication by inducing cap-independent, internal initiation mediated translation of a novel viral protein (named ORF4). Importantly, ORF4 expression and stimulatory effect of ER stress inducers on viral replication is specific to genotype-1. ORF4 protein sequence is mostly conserved among genotype-1 HEV isolates and ORF4 specific antibodies were detected in genotype-1 HEV patient serum. ORF4 interacted with multiple viral and host proteins and assembled a protein complex consisting of viral helicase, RNA dependent RNA polymerase (RdRp), X, host eEF1α1 (eukaryotic elongation factor 1 isoform-1) and tubulinß. In association with eEF1α1, ORF4 stimulated viral RdRp activity. Furthermore, human hepatoma cells that stably express ORF4 or engineered proteasome resistant ORF4 mutant genome permitted enhanced viral replication. These findings reveal a positive role of ER stress in promoting genotype-1 HEV replication and pave the way towards development of an efficient model of the virus.

Neurotrophic factor mediated neuronal differentiation of human cord blood mesenchymal stem cells and their applicability to assess the developmental neurotoxicity.

Plasticity and developmental capacity of stem cells have now been established as a promising tool to restore the degenerative disorders. The linearity differentiation of human mesenchymal stem cells (hMSCs) into adipogenic, chondrogenic, osteogenic and even in neuronal subtypes has been demonstrated. The number of xenobiotics such as dexamethasone, insulin, isobutyl 1-methyle xanthine and retinoic acid has been reported for the potential to differentiate hMSCs into neuronal subtypes. But, the applicability of indigenous neurotrophic factor-nerve growth factor (NGF) has not been explored for the purpose. Thus, the present investigations were carried out to study the NGF induced neuronal differentiation of hMSCs. Following the isolation, purification and characterization of hMSCs were allowed to differentiate into neuronal subtypes under the influence of NGF (50 ng/mL). At various concentrations of NGF, the neuronal makers were analysed at both mRNA and protein levels. Cells, exposed with NGF were showing the significant and gradual increase in the neuronal markers in differentiating cells. The magnitude of expression of markers was maximum at day 4 of differentiation. NGF at 50 ng/mL concentration was found to induce neuronal differentiation of hMSCs into neuronal subtypes.

Peripheral MC1R activation modulates immune responses and is neuroprotective in a mouse model of Parkinson's disease.

Background: Melanocortin 1 receptor (MC1R) is a key pigmentation gene, and loss-of-function of MC1R variants that produce red hair may be associated with Parkinson's disease (PD). We previously reported compromised dopaminergic neuron survival in Mc1r mutant mice and dopaminergic neuroprotective effects of local injection of a MC1R agonist to the brain or a systemically administered MC1R agonist with appreciable CNS permeability. Beyond melanocytes and dopaminergic neurons, MC1R is expressed in other peripheral tissues and cell types, including immune cells. The present study investigates the impact of NDP-MSH, a synthetic melanocortin receptor (MCR) agonist that does not cross BBB, on the immune system and the nigrostriatal dopaminergic system in mouse model of PD. Methods: C57BL/6 mice were treated systemically with MPTP.HCl (20 mg/kg) and LPS (1 mg/kg) from day 1 to day 4 and NDP-MSH (400 µg/kg) or vehicle from day 1 to day 12 following which the mice were sacrificed. Peripheral and CNS immune cells were phenotyped and inflammatory markers were measured. The nigrostriatal dopaminergic system was assessed behaviorally, chemically, immunologically, and pathologically. To understand the role of regulatory T cells (Tregs) in this model, CD25 monoclonal antibody was used to deplete CD25+ Tregs. Results: Systemic NDP-MSH administration significantly attenuated striatal dopamine depletion and nigral dopaminergic neuron loss induced by MPTP+LPS. It improved the behavioral outcomes in the pole test. Mc1r mutant mice injected with NDP-MSH in the MPTP and LPS paradigm showed no changes in striatal dopamine levels suggesting that the NDP-MSH acts through the MC1R pathway. Although no NDP-MSH was detected in the brain, peripheral, NDP-MSH attenuated neuroinflammation as observed by diminished microglial activation in the nigral region, along with reduced TNF-α and IL1ß levels in the ventral midbrain. Depletion of Tregs limited the neuroprotective effects of NDP-MSH. Conclusions: Our study demonstrates that peripherally acting NDP-MSH confers protection on dopaminergic nigrostriatal neurons and reduces hyperactivated microglia. NDP-MSH modulates peripheral immune responses, and Tregs may be involved in the neuroprotective effect of NDP-MSH.

Peripheral MC1R Activation Modulates Immune Responses and is Neuroprotective in a Mouse Model of Parkinson's Disease.

BACKGROUND: Melanocortin 1 receptor (MC1R) is a key pigmentation gene, and loss-of-function of MC1R variants that produce red hair may be associated with Parkinson's disease (PD). We previously reported compromised dopaminergic neuron survival in Mc1r mutant mice and dopaminergic neuroprotective effects of local injection of a MC1R agonist to the brain or a systemically administered MC1R agonist with appreciable central nervous system (CNS) permeability. Beyond melanocytes and dopaminergic neurons, MC1R is expressed in other peripheral tissues and cell types, including immune cells. The present study investigates the impact of NDP-MSH, a synthetic melanocortin receptor (MCR) agonist that does not cross BBB, on the immune system and the nigrostriatal dopaminergic system in mouse model of PD. METHODS: C57BL/6 mice were treated systemically with MPTP.HCl (20 mg/kg) and LPS (1 mg/kg) from day 1 to day 4 and NDP-MSH (400 µg/kg) or vehicle from day 1 to day 12 following which the mice were sacrificed. Peripheral and CNS immune cells were phenotyped and inflammatory markers were measured. The nigrostriatal dopaminergic system was assessed behaviorally, chemically, immunologically, and pathologically. To understand the role of regulatory T cells (Tregs) in this model, CD25 monoclonal antibody was used to deplete CD25 + Tregs. RESULTS: Systemic NDP-MSH administration significantly attenuated striatal dopamine depletion and nigral dopaminergic neuron loss induced by MPTP + LPS. It improved the behavioral outcomes in the pole test. Mc1r mutant mice injected with NDP-MSH in the MPTP and LPS paradigm showed no changes in striatal dopamine levels suggesting that the NDP-MSH acts through the MC1R pathway. Although no NDP-MSH was detected in the brain, peripheral, NDP-MSH attenuated neuroinflammation as observed by diminished microglial activation in the nigral region, along with reduced TNF-α and IL1ß levels in the ventral midbrain. Depletion of Tregs was associated with diminished neuroprotective effects of NDP-MSH. CONCLUSIONS: Our study demonstrates that peripherally acting NDP-MSH confers protection on dopaminergic nigrostriatal neurons and reduces hyperactivated microglia. NDP-MSH modulates peripheral immune responses, and Tregs may be involved in the neuroprotective effect of NDP-MSH.

Nonlinear dynamics of a SIRI model incorporating the impact of information and saturated treatment with optimal control.

In this article, we propose and analyze an infectious disease model with reinfection and investigate disease dynamics by incorporating saturated treatment and information effect. In the model, we consider the case where an individual's immunity deteriorates and they become infected again after recovering. According to our findings, multiple steady states and backward bifurcation may occur as a result of treatment saturation. Further, if treatment is available for all, the disease will be eradicated provided R 0 < 1 ; however, because limited medical resources caused saturation in treatment, the disease may persist even if R 0 < 1 . The global stability of the unique endemic steady state is established using a geometric approach. We also establish certain conditions on the transmission rate for the occurrence of periodic oscillations in the model system. Among nonlinear dynamics, we show supercritical Hopf bifurcation, bi-stability, backward Hopf bifurcation, and double Hopf bifurcation. To illustrate and validate our theoretical results, we present numerical examples. We found that when disease information coverage is high, infection cases fall considerably, and the disease persists when the reinfection rate is high. We then extend our model by incorporating two time-dependent controls, namely inhibitory interventions and treatment. Using Pontryagin's maximum principle, we prove the existence of optimal control paths and find the optimal pair of controls. According to our numerical simulations, the second control is less effective than the first. Furthermore, while implementing a single intervention at a time may be effective, combining both interventions is most effective in reducing disease burden and cost.

Plasmodium falciparum Antigen Expression in Leishmania Parasite: A Way Forward for Live Attenuated Vaccine Development.

Live attenuated vaccines (LAVs) are among the most critical interventions in modern medicine and have already proven their potential to save millions of lives. LAVs are always explored as potential vaccine candidates since they induce an immune response, which is as good as the wild type pathogen. For parasitic diseases, the efficacy of LAVs is still under investigation and needs extensive research to mark their presence in the field. In malaria, live attenuated sporozoites have been evaluated for a vaccine against the liver stage. This vaccine approach is limited due to the highly cumbersome technique of sporozoite isolation and related relapse issues. We have developed a novel vaccine against malaria by expressing Plasmodium falciparum antigens in Leishmania donovani promastigotes. These hybrid, recombinant L. donovani parasites mimicking P. falciparum parasite antigens were analyzed for their anti-malarial efficacy in preclinical studies. We demonstrate the potential of Leishmania spp. parasites in developing an important live vector vaccine against malaria for the induction of protective immune responses. Herein, we describe a method to express malaria parasite antigens in L. donovani promastigotes and analyze its potential for a vaccine against malaria. This methodology can be extended to live, attenuated Leishmania promastigotes parasites to develop LAV against malaria.

Pathogenic Pore Forming Proteins of Plasmodium Triggers the Necrosis of Endothelial Cells Attributed to Malaria Severity.

Severe malaria caused by Plasmodium falciparum poses a major global health problem with high morbidity and mortality. P. falciparum harbors a family of pore-forming proteins (PFPs), known as perforin like proteins (PLPs), which are structurally equivalent to prokaryotic PFPs. These PLPs are secreted from the parasites and, they contribute to disease pathogenesis by interacting with host cells. The severe malaria pathogenesis is associated with the dysfunction of various barrier cells, including endothelial cells (EC). Several factors, including PLPs secreted by parasites, contribute to the host cell dysfunction. Herein, we have tested the hypothesis that PLPs mediate dysfunction of barrier cells and might have a role in disease pathogenesis. We analyzed various dysfunctions in barrier cells following rPLP2 exposure and demonstrate that it causes an increase in intracellular Ca2+ levels. Additionally, rPLP2 exposed barrier cells displayed features of cell death, including Annexin/PI positivity, depolarized the mitochondrial membrane potential, and ROS generation. We have further performed the time-lapse video microscopy of barrier cells and found that the treatment of rPLP2 triggers their membrane blebbing. The cytoplasmic localization of HMGB1, a marker of necrosis, further confirmed the necrotic type of cell death. This study highlights the role of parasite factor PLP in endothelial dysfunction and provides a rationale for the design of adjunct therapies against severe malaria.

Metabotropic Glutamate Receptors in Alzheimer's Disease Synaptic Dysfunction: Therapeutic Opportunities and Hope for the Future.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the presence of neuritic plaques and neurofibrillary tangles. The impaired synaptic plasticity and dendritic loss at the synaptic level is an early event associated with the AD pathogenesis. The abnormal accumulation of soluble oligomeric amyloid-ß (Aß), the major toxic component in amyloid plaques, is viewed to trigger synaptic dysfunctions through binding to several presynaptic and postsynaptic partners and thus to disrupt synaptic transmission. Over time, the abnormalities in neural transmission will result in cognitive deficits, which are commonly manifested as memory loss in AD patients. Synaptic plasticity is regulated through glutamate transmission, which is mediated by various glutamate receptors. Here we review recent progresses in the study of metabotropic glutamate receptors (mGluRs) in AD cognition. We will discuss the role of mGluRs in synaptic plasticity and their modulation as a possible strategy for AD cognitive improvement.

Author Correction: Molecular Mechanism of Switching of TrkA/p75NTR Signaling in Monocrotophos Induced Neurotoxicity.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Expression, Purification and Characterization of the Hepatitis E Virus Like-Particles in the Pichia pastoris.

Hepatitis E virus (HEV) is associated with acute hepatitis disease, which may lead to chronic disease in immunocompromised individuals. The disease is particularly severe among pregnant women (20-30% mortality). The only licensed vaccine against HEV, which is available in China, is the Escherichia coli purified recombinant virus-like particles (VLPs) encompassing the 368-660 amino acids (aa) of the viral ORF2 protein. The viral capsid is formed by the ORF2 protein, which harbors three glycosylation sites. Baculo virus expression system has been employed to generate a glycosylated VLP, which encompasses 112-608aa of the ORF2 protein. Here, we sought to produce a recombinant VLP containing 112-608aa of the ORF2 protein in Pichia pastoris (P. pastoris) expression system. The cDNA sequence encoding 112-608aa of the ORF2 protein was fused with the α-mating factor secretion signal coding sequence (for release of the fusion protein to the culture medium) and cloned into the yeast vector pPICZα. Optimum expression of recombinant protein was obtained at 72 h induction in 1.5% methanol using inoculum density (A600) of 80 and at pH-3.0 of the culture medium. Identity of the purified protein was confirmed by mass spectrometry analysis. Further studies revealed the glycosylation pattern and VLP nature of the purified protein. Immunization of BALB/c mice with these VLPs induced potent immune response as evidenced by the high ORF2 specific IgG titer and augmented splenocyte proliferation in a dose dependent manner. 112-608aa ORF2 VLPs produced in P. pastoris appears to be a suitable candidate for development of diagnostic and prophylactic reagents against the hepatitis E.

Role of bone marrow-derived macrophages (BMDMs) in neurovascular interactions during stroke.

Stroke is a leading cause of disability worldwide and hence remains a major medical concern. Besides several pathological features, such as excitotoxicity, peri-infarct depolarization, acidosis, reactive oxygen species generation, apoptosis, and necrosis, dysregulation of the immune system severely affects stroke outcomes. After stroke onset, microglia - the brain-resident macrophage immune cells - and peripheral immune cells affect stoke injury/recovery by releasing pro-inflammatory and/or anti-inflammatory cytokines depending on their microenvironment. These pro- or anti-inflammatory cytokines further affect integrity of the blood brain barrier (BBB) and modulate immune infiltration after stroke. Among peripheral immune cells, bone marrow-derived macrophages (BMDMs) play a critical role in stroke pathology which peaks between three and seven days post-stroke. BMDMs have been extensively studied for their role in exacerbation of stroke injury, however they have rarely been studied for their role in tissue repair. Nonetheless, these reparative roles are gaining attention since recent studies have shown either failure or worsening of long-term post-stroke recovery after blockade of peripheral immune infiltration. These diverse but paradoxical effects of infiltrating monocytes/macrophages encouraged us to summarize the latest findings in neuro-immune and immune-vascular interactions. This review highlights the multifaceted role of BMDMs in stroke onset and resolution, and emphasizes the significance of tapping the potential of these cells to gain better insight into disease progression and therapy.

Identification and functional characterization of a bacterial homologue of Zeta toxin in Leishmania donovani.

Zeta-toxin is a cognate toxin of epsilon antitoxin of prokaryotic Type II toxin-antitoxin system (TA) and play an important role in cell death. An orthologue of bacterial-zeta-toxin (BzT) was identified in Leishmania donovani with similar structural and functional features. Leishmania zeta-toxin (named Ld_ζ1) harboring similar UNAG and ATP-binding pockets showed UNAG kinase and ATP-binding activity. An active Ld_ζ1 was found to express in infective extracellular promastigotes stage of L. donovani and episomal overexpression of an active Ld_ζ1domain-triggered cell death. This study demonstrates the presence of prokaryotic-like-zeta-toxin in eukaryotic parasite Leishmania and its association with cell death. Conceivably, phosphorylated UNAG or analogues, the biochemical mimics of zeta-toxin function mediating cell death can act as a novel anti-leishmanial chemotherapeutics.

Host-Virus Protein Interaction Network Reveals the Involvement of Multiple Host Processes in the Life Cycle of Hepatitis E Virus.

Comprehensive knowledge of host-pathogen interactions is central to understand the life cycle of a pathogen and devise specific therapeutic strategies. Protein-protein interactions (PPIs) are key mediators of host-pathogen interactions. Hepatitis E virus (HEV) is a major cause of viral hepatitis in humans. Recent reports also demonstrate its extrahepatic manifestations in the brain. Toward understanding the molecular details of HEV life cycle, we screened human liver and fetal brain cDNA libraries to identify the host interaction partners of proteins encoded by genotype 1 HEV and constructed the virus-host PPI network. Analysis of the network indicated a role of HEV proteins in modulating multiple host biological processes such as stress and immune responses, the ubiquitin-proteasome system, energy and iron metabolism, and protein translation. Further investigations revealed the presence of multiple host translation regulatory factors in the viral translation/replication complex. Depletion of host translation factors such as eIF4A2, eIF3A, and RACK1 significantly reduced the viral replication, whereas eIF2AK4 depletion had no effect. These findings highlight the ingenuity of the pathogen in manipulating the host machinery to its own benefit, a clear understanding of which is essential for the identification of strategic targets and development of specific antivirals against HEV. IMPORTANCE Hepatitis E virus (HEV) is a pathogen that is transmitted by the fecal-oral route. Owing to the lack of an efficient laboratory model, the life cycle of the virus is poorly understood. During the course of infection, interactions between the viral and host proteins play essential roles, a clear understanding of which is essential to decode the life cycle of the virus. In this study, we identified the direct host interaction partners of all HEV proteins and generated a PPI network. Our functional analysis of the HEV-human PPI network reveals a role of HEV proteins in modulating multiple host biological processes such as stress and immune responses, the ubiquitin-proteasome system, energy and iron metabolism, and protein translation. Further investigations revealed an essential role of several host factors in HEV replication. Collectively, the results from our study provide a vast resource of PPI data from HEV and its human host and identify the molecular components of the viral translation/replication machinery.

PI3K/Akt/GSK3ß induced CREB activation ameliorates arsenic mediated alterations in NMDA receptors and associated signaling in rat hippocampus: Neuroprotective role of curcumin.

Protective efficacy of curcumin in arsenic induced NMDA receptor dysfunctions and PI3K/Akt/ GSK3ß signalling in hippocampus has been investigated in vivo and in vitro. Exposure to sodium arsenite (in vivo - 20 mg/kg, body weight p.o. for 28 days; in vitro - 10 µM for 24 h) and curcumin (in vivo - 100 mg/kg body weight p.o. for 28 days; in vitro - 20 µM for 24 h) was carried out alone or simultaneously. Treatment with curcumin ameliorated sodium arsenite induced alterations in the levels of NMDA receptors, its receptor subunits and synaptic proteins - pCaMKIIα, PSD-95 and SynGAP both in vivo and in vitro. Decreased levels of BDNF, pAkt, pERK1/2, pGSK3ß and pCREB on sodium arsenite exposure were also protected by curcumin. Curcumin was found to decrease sodium arsenite induced changes in hippocampus by modulating PI3K/Akt/GSK3ß neuronal survival pathway, known to regulate various cellular events. Treatment of hippocampal cultures with pharmacological inhibitors for ERK1/2, GSK3ß and Akt individually inhibited levels of CREB and proteins associated with PI3K/Akt/GSK3ß pathway. Simultaneous treatment with curcumin was found to improve sodium arsenite induced learning and memory deficits in rats assessed by water maze and Y-maze. The results provide evidence that curcumin exercises its neuroprotective effect involving PI3K/Akt pathway which may affect NMDA receptors and downstream signalling through TrKß and BDNF in arsenic induced cognitive deficits in hippocampus.

Iminosugar C-Nitromethyl Glycosides and Divergent Synthesis of Bicyclic Iminosugars.

An efficient one-pot method for the stereoselective synthesis of novel iminosugar C-nitromethyl glycosides is described. This new class of iminosugar glycosides has versatile nitromethyl functionality whose utility was further demonstrated in the single-step synthesis of bicyclic iminosugars. Under reagent-free conditions, the N-allyl-C-nitromethyl glycosides resulted in intramolecular cyclization to iminosugar-oximes, whereas under SET oxidation, they furnished cyclopropane-fused iminosugars. The N-propargyl-C-nitromethyl glycosides underwent an unprecedented ketenimine-acrylamidine-Michael addition cascade reaction to give bicyclic amidines.

RNA-dependent RNA Polymerase Assay for Hepatitis E Virus.

RNA-dependent RNA polymerase (RdRp) is essential for the replication of viral RNA for RNA viruses. It synthesizes the complementary strand of viral genomic RNA, which is used subsequently as a template to generate more copies of viral genome. This assay measures activity of the hepatitis E virus (HEV) RdRp. In contrast to protocols available to assay the RdRp activity of many other viruses, this assay utilizes DIG-11-UTP as a nonradioactive alternative to 32P-UTP, thereby increasing the convenience of performing the assay.