IDENTIFICATION OF POTENTIAL NOVEL EGFR INHIBITORS USING A COMBINATION OF PHARMACOPHORE AND DOCKING METHODS

Objective: Identifying new inhibitors of Epidermal Growth Factor Receptor (EGFR) by virtual screening using a pharmacophore model followed by docking. Methods: A pharmacophore model was developed using a dataset of 77 chemically diverse EGFR inhibitors using PHASE. Statistically valid Three Dimensional Quantitative Structure Activity Relationship (3D-QSAR) equations were generated for the pharmacophore model. This was followed by database screening to obtain probable hits. Docking of the probable hits into the crystal structure of EGFR was used as a second filter. Docking studies were carried out using GLIDE. Calculation of ADME properties of the probable hits arising out of docking further reduced the number of hits. Results: A five-point pharmacophore was generated for EGFR inhibitors reported in literature. The pharmacophore indicated that the presence of two aromatic ring features (R), one acceptor feature (A), one donor feature (D) and one hydrophobic feature (H) is necessary for potent inhibitory activity. The generated pharmacophore yielded statistically significant 3D-QSAR model, with a correlation coefficient r2 of 0.9905 and q2 of 0.8764. Virtual screening using the best pharmacophore model resulted in 372 hits. Docking studies as a second filter reduced the hits to 8. Application of drug-likeness as a third filter gave 6 leads.Conclusion: 6 leads with satisfactory pharmacokinetics properties were identified as potential EGFR inhibitors. This study may facilitate development of some new potential EGFR inhibitors. Â

Studies on Adsorption of Organic Compounds at Mercury-Solution Interface: Individual & Simultaneous Adsorption of p-Aminobenzoic Acid & Sulphanilamide

749-75

LOCALIZATION AND ORIENTATION OF METHOXY FLAVONOIDS IN DPPC BILAYERS: EFFECT ON THEIR ANTI-PROLIFERATIVE ACTIVITY

Objective: Flavones and flavonols are an important class of naturally occurring flavonoids. They are well known for their pharmacological activity. This activity is associated with the ability of flavones and flavonols to influence membrane–dependent processes. In this paper, we have reported localization, orientation and interaction, of four synthesized flavone/flavonols with 1, 2–dipalmitoyl–sn–glycero–3–phosphocholine (DPPC) bilayers. These are compared with standard flavone; chrysin (CHY) and flavonol Quercetin (QUE).Methods: The molecules studied are 4ʹ–methoxy flavone (MF), 3ʹ,4ʹ–dimethoxyflavone (DMF), 4ʹ–methoxyflavonol (MF–ol) and 3ʹ,4ʹ–dimethoxyflavonol (DMF–ol). The techniques used are Differential Scanning Calorimetry (DSC) and multi–nuclear NMR.Results: Highest binding to lipid bilayers is shown by DMF, followed by QUE. Based on DSC studies it is seen, that maximum interaction of MF and DMF, takes place with the hydrophobic core of lipid bilayers. DMF–ol shows formation of a heterogeneous system at higher concentrations. The 1H NMR spectra of unilamellar vesicles of DPPC, incorporated with MF, DMF and MF–ol shows significant interaction of these compounds with the alkyl chain of the hydrophobic core. MF, DMF and MF–ol acquire parallel orientation in bilayers with the B–ring pointing towards hydrophobic core, while DMF–ol acquire mixed orientation. This may be ascribed to the presence of two methoxy and one hydroxyl group on the B–ring of DMF–ol which hinders its partitioning inside the hydrophobic core of lipid bilayer. Multi–lamellar vesicles (MLV) of DPPC incorporated with flavones, show maximum increase in Chemical Shift Anisotropy in 31P spectrum of DMF. This is followed by MF. DSC.Conclusion: NMR and binding studies indicate that DMF is partitioned deeply inside the hydrophobic core, while MF, MF–ol and DMF–ol are mostly located in the vicinity of sn–glycero region. Therefore, we conclude that DMF which penetrates deepest inside the hydrophobic core also shows the highest anti–proliferative activity against K562 and MCF–7 cancer cell lines. Its activity is also better than CHY

EFFECT OF METHYL SUBSTITUTION IN FLAVONES ON ITS LOCALIZATION AND INTERACTION WITH DPPC MODEL MEMBRANE: IMPLICATIONS FOR ANTI-PROLIFERATIVE ACTIVITY

Objective: Flavones are an important class of naturally occurring molecules possessing multiple pharmacological activities. The anti-proliferative activity is associated with the ability of flavones to influence membrane–dependent processes. We have investigated the localization and interaction of the synthesized flavones: 4΄–methylflavone (4MF) and 4΄–methyl–7–hydroxy flavone (4M7HF) with 1,2–dipalmitoyl–sn–glycero–3–phosphocholine (DPPC) model membrane. Methods: Diferential Scanning Calorimetry (DSC) and multi nuclear NMR were used to study the interactions with DPPC model membrane. The extent of interaction of these compounds has been compared with the parent molecules: flavone (FLV) and 7–hydroxy flavone (7HF). Results: Results of DSC and NMR indicate that FLV partitions deepest inside the hydrophobic core and 7HF is localized mostly at the lipid/water interface. 4MF and 4M7HF lying in between the hydrophilic and hydrophobic core. All four molecules assume a mixed orientation with respect to the bilayer normal as indicated by chemical shifts of the lipid protons in NMR. Interaction with the membrane follows the order FLV>4MF>4M7HF>7HF. Radical scavenging activity parallels the presence of hydroxyl groups. Although FLV interacts highest with the membrane, it does not show highest antiproliferative activity. Interaction of the compounds with protons 3, 5a and 7 of DPPC is improved by the methyl substitution on the B-ring, so is the antiproliferative activity. Conclusion: That's antiproliferative activity of the compounds is at least partially related to the interaction of these molecules with the lipid water interface region

Curation of viral genomes: challenges, applications and the way forward

BACKGROUND: Whole genome sequence data is a step towards generating the 'parts list' of life to understand the underlying principles of Biocomplexity. Genome sequencing initiatives of human and model organisms are targeted efforts towards understanding principles of evolution with an application envisaged to improve human health. These efforts culminated in the development of dedicated resources. Whereas a large number of viral genomes have been sequenced by groups or individuals with an interest to study antigenic variation amongst strains and species. These independent efforts enabled viruses to attain the status of 'best-represented taxa' with the highest number of genomes. However, due to lack of concerted efforts, viral genomic sequences merely remained as entries in the public repositories until recently. RESULTS: VirGen is a curated resource of viral genomes and their analyses. Since its first release, it has grown both in terms of coverage of viral families and development of new modules for annotation and analysis. The current release (2.0) includes data for twenty-five families with broad host range as against eight in the first release. The taxonomic description of viruses in VirGen is in accordance with the ICTV nomenclature. A well-characterised strain is identified as a 'representative entry' for every viral species. This non-redundant dataset is used for subsequent annotation and analyses using sequenced-based Bioinformatics approaches. VirGen archives precomputed data on genome and proteome comparisons. A new data module that provides structures of viral proteins available in PDB has been incorporated recently. One of the unique features of VirGen is predicted conformational and sequential epitopes of known antigenic proteins using in-house developed algorithms, a step towards reverse vaccinology. CONCLUSION: Structured organization of genomic data facilitates use of data mining tools, which provides opportunities for knowledge discovery. One of the approaches to achieve this goal is to carry out functional annotations using comparative genomics. VirGen, a comprehensive viral genome resource that serves as an annotation and analysis pipeline has been developed for the curation of public domain viral genome data . Various steps in the curation and annotation of the genomic data and applications of the value-added derived data are substantiated with case studies

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden