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"This book about first-principles-based multiscale, multiparadigm molecular mechanics and dynamics methods for describing complex chemical processes, dynamic QM/MM : a hybrid approach to simulating gas–liquid interactions, multiscale modelling in computational heterogeneous catalysis, real-world predictions from Ab initio molecular dynamics simulations, nanoscale wetting under electric field from molecular simulations, molecular simulations of retention in chromatographic systems : use of biased Monte Carlo techniques to access multiple time and length scales, thermodynamic properties for applications in chemical industry via classical force fields, multiscale approaches and perspectives to modeling aqueous electrolytes and polyelectrolytes, and coarse-grained modeling for macromolecular chemistry."

"Sebagai upaya dalam memahami netralisasi virus H5N1 oleh antibodi manusia, simulasi dinamika molekuler dua kompleks antibodi-antigen dilakukan. Tiga struktur molekul yang membentuk dua kompleks tersbeut dibentuk termasuk antigen hemagglutinin Vietnam 2IBX, hemagglutinin Indonesia CDC, dan fragmen variabel dari antibodi 8H5 atau 8H5Fv.Dalam penelitian ini komplesks 8H5Fv-2IBX dan 8H5Fv-CDC diproduksi melalui pemodelan struktur molekul, homology modeling, dan molecular docking. Dua kompleks tersebut lalu melewati simulasi dinamika molekuler selama 2 nanosekon untuk menginvestigasi kestabilan struktur kompleks dan aktivitas netralisasi yang dapat diamati dengan berfokus pada epitope netralisasi masing ? masing hemagglutinin yang didapatkan hasil molecular docking.Didapatkan bahwa sifat dinamis atom ? atom pembentuk molekul tidak menihilkan aktivitas netralisasi. Dengan mengamati epitope netralisasi masing ? masing hemagglutinin juga didapatkan bahwa aktivitas netralisasi lebih efektif pada hemagglutinin 2IBX (Vietnam) dibandingkan dengan hemagglutinin Indonesia (CDC) berdasarkan kalkulasi solvent accessible surface (SAS), energi, root mean square displacement (RMSD), dan analisis okupansi ikatan hidrogen.

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In an effort to study the H5N1 virus neutralisation by a human antibody, molecular dynamics simulations on two antibody-antigen complexes were conducted. Three molecular structures were formed in this study including the Vietnamese hemagglutinin 2IBX, the Indonesian hemagglutinin CDC, and a variable fragment of the 8H5 antibody or 8H5Fv.

In this study the complexes 8H5Fv-2IBX and 8H5Fv-CDC, that were produced by molecular modeling, homology modeling and molecular docking, was subjected to a 2 nanosecond molecular dynamics simulation each to investigate the stability of such complexes and the maintenance of the neutralising activity that was observed by focusing on the neutralising epitopes that were predicted by molecular docking.

It is was found that the dynamic nature of the molecules in study did not negate the steric hindrance occuring from the antibody variable fragment 8H5Fv with the hemagglutinins, therefore suggesting that the 8H5 antibody should be able to neutralise these two hemagglutinins. By solvent accessible surface (SAS) calculations, energy analysis, root mean square displacement (RMSD) analysis, and also hydrogen bond occupance it was also found that the the 8H5Fv seem to be more effective against the 2IBX (Vietnamese) hemagglutinin than against the CDC (Indonesian) hemagglutinin."

"Penyakit yang disebabkan oleh infeksi virus dengue telah menjadi salah satu masalah kesehatan yang utama di dunia, terutama Asia, Afrika, dan Amerika. Infeksi ini telah menjadi endemik di lebih dari 100 negara. World Health Organization memperkirakan terjadi 100 juta kasus tiap tahun dan sebanyak 2,5 miliar orang atau 40% dari populasi dunia berisiko terjangkit infeksi virus ini. Oleh karena itu, dibutuhkan suatu pengobatan yang bersifat antiviral yang dapat menghambat aktivitas enzim yang berperan dalam replikasi di dalam tubuh. Akhir-akhir ini peptida telah dikembangkan dalam drug design. Dalam penelitian ini digunakan peptida yang sudah dipasarkan secara komersial. Tujuan penelitian ini adalah untuk penapisan peptida siklis komersial yang dapat digunakan sebagai inhibitor protein NS2B-NS3 DENV melalui metode penambatan molekul dan simulasi dinamika molekul. Inhibisi terhadap enzim NS3 protease dapat menyebabkan terhambatnya aktivitas enzimatiknya sehingga poliprotein yang terbentuk dari translasi RNA menjadi tidak dapat dipotong-potong dan poliprotein tetap berada dalam bentuk satu untai panjang yang utuh. Akibatnya protein protein lain yang vital bagi keberlangsungan replikasi virus dengue tidak dapat terbentuk. Penelitian ini menghasilkan ligan Atrial Natriuretic Factor (3-28) (human) sebagai kandidat obat terbaik. Simulasi dinamika molekul menunjukkan bahwa senyawa ini tetap stabil pada kenaikan suhu tubuh menjadi 312 K.

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A disease caused by dengue virus infection has become one of the major health problems in the world, especially Asia, Africa, and America. This infection has become endemic in more than 100 countries. The World Health Organization estimates that 100 million cases occur each year and as many as 2.5 billion people or 40% of the world population at risk of contracting this virus infection. Therefore, we need an antiviral that can inhibit the activity of enzymes involved in the replication in the body. Lately peptide drug design has been developed. This study uses peptides that has been marketed commercially.

The purpose of this study was to screen the commercial cyclic peptides that can be used as an inhibitor of NS3 protein NS2B DENV-through molecular docking and molecular dynamics simulations. Inhibition of NS3 protease enzyme can lead to inhibition of enzymatic activity so polyprotein formed from the translation of RNA can not be cut into pieces and polyprotein remain in the form of a long strand. Proteins that consequently vital for the sustainability of dengue virus replication can not be formed.

This research resulted Atrial natriuretic factor (3-28) (human) as the best drug candidate. Molecular dynamics simulations indicate that this compound remains stable at body temperature of 312 K."

"Demam berdarah merupakan penyakit yang disebarkan melalui virus DEN-V dengan perantara nyamuk. Penyakit ini berbahaya karena belum ada obat, vaksin, ataupun antiviral khusus terhadap virus DEN-V, sehingga perlu dilakukan penemuan obat untuk demam berdarah. Enzim RNA dependent RNA polymerase (Rdrp) pada DEN-V dapat dijadikan target obat karena berperan penting pada proses replikasi virus. Pada penelitian ini dilakukan simulasi in silico terhadap tiga senyawa bioflavonoid, sub-kelas flavanon, yaitu Hesperetin, Hesperidin, dan Naringenin. Simulasi penambatan molekuler dan dinamika molekuler dilakukan untuk mengetahui kebolehjadian senyawa tersebut sebagai inhibitor target Rdrp. Hasil simulasi senyawa flavanon dibandingkan dengan Quercetin, dengan parameter penilaian penambatan molekuler, energi ikatan, RMSD, RMSF, dan kontak ligan-target. Hasil nilai penambatan molekuler untuk masing-masing ligan terendah yaitu Hesperidin, Quercetin, Hesperetin, dan Naringenin dengan nilai berturut-turut yaitu -9,842 kcal/mol, -8,513 kcal/mol, -7,761 kcal/mol, dan -5,634 kcal/mol. Hasil MM-GBSA energi ikatan terbaik adalah ligan Hesperidin, Naringenin, Hesperetin, dan Quercetin dengan nilai ikatan energi bebas secara berturut-turut yaitu -69,31 kcal/mol, -64,90 kcal/mol, -60,93 kcal/mol, dan -57,83 kcal/mol. Hasil dari studi ini memprediksi bahwa Hesperidin dapat menjadi inhibitor terhadap target Rdrp yang lebih baik dibandingkan Quercetin, sementara Hesperetin dan Naringenin juga memiliki aktivitas inhibisi tetapi tidak sebaik Quercetin.

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Dengue fever is a disease spread by the DEN-V virus through mosquitoes. This disease is dangerous because there is no specific drug, vaccine, or antiviral against the DEN-V virus, insisting the need of drug discovery for dengue fever. RNA dependent RNA polymerase (Rdrp) enzyme in DEN-V can be a drug target because it has an important role in the virus replication process. In this research, in silico simulations were carried out on bioflavonoid compounds, flavanone sub-class, namely Hesperetin, Hesperidin, and Naringenin. Molecular docking simulations and molecular dynamics were carried out to determine the probability of these compounds to be inhibitors of Rdrp targets. The results obtained from the simulation of the flavanones was compared with quercetin, which are docking score, energy binding, RMSD, RMSF, and ligand-target contact. The molecular docking results, docking score, for each of all ligands from the lowest were Hesperidin, Quercetin, Hesperetin, and Naringenin with values of -9.842 kcal/mol, -8.513 kcal/mol, -7.761 kcal/mol, and -5.634 kcal/mol, respectively. The best bond energy MM-GBSA results were Hesperidin, Naringenin, Hesperetin, and Quercetin with the value of free energy bonding respectively, namely -69.31 kcal/mol, -64.90 kcal/mol, -60.93 kcal/mol , and -57.83 kcal/mol. The results of this study predict that Hesperidin can be a better inhibitor to target Rdrp than Quercetin, while Hesperetin and Naringenin also have inhibitory activity but not as well as Quercetin."

"Molecular modeling and multiscaling issues for electronic material applications provides a snapshot on the progression of molecular modeling in the electronics industry and how molecular modeling is currently being used to understand material performance to solve relevant issues in this field. This book is intended to introduce the reader to the evolving role of molecular modeling, especially seen through the eyes of the IEEE community involved in material modeling for electronic applications. Part I presents the role that quantum mechanics can play in performance prediction, such as properties dependent upon electronic structure, but also shows examples how molecular models may be used in performance diagnostics, especially when chemistry is part of the performance issue. Part II gives examples of large-scale atomistic methods in material failure and shows several examples of transitioning between grain boundary simulations (on the atomistic level)and large-scale models including an example of the use of quasi-continuum methods that are being used to address multiscaling issues. Part III is a more specific look at molecular dynamics in the determination of the thermal conductivity of carbon-nanotubes. Part IV covers the many aspects of molecular modeling needed to understand the relationship between the molecular structure and mechanical performance of materials. Finally, part V discusses the transitional topic of multiscale modeling and recent developments to reach the submicronscale using mesoscale models, including examples of direct scaling and parameterization from the atomistic to the coarse-grained particle level."

"Applied nanotechnology takes an integrated approach to the scientific, commercial and social aspects of nanotechnology, exploring :

- The relationship between nanotechnology and innovation

- The changing economics and business models required to commercialize innovations in nanotechnology

- Product design case studies

- Applications in various sectors, including information technology, composite materials, energy, and agriculture

- The role of government in promoting nanotechnology

- The potential future of molecular self-assembly in industrial production

In this 2e, new chapters have been added on energy applications and the role of nanotechnology in sustainability. The section on the safety of nanoproducts has also been updated, and material on funding and commercialization has been updated and expanded, with new case studies illustrating the experience of new startups in a challenging economic environment."

"Rem GTPase is a member ofRGK subfamily (Rad, Rem, Rem2, Gem and Kir) found recently. Rem is highly expressed at cardiac muscle.[l] Crystal structure of Rem (2NZJ) unveiled disordered structures of switch I (residue 102-110) and switch II (residue 135-145). These both regions have been acknowledged to be involved in nucleotide binding and GTP hydrolysis . The purpose of this study is to construct Rem GTPase model by using homology modeling method and to analyze the movements of Rem by performing molecular dynamics (MD) simulation. The selected Rem model, model_Rem_6.pdb, was constructed from multiple templates composed of 421P _A (Ras), 2A78_A (RalA), and 2NZJ_A. Furthermore Rem model was used for ten nanoseconds MD simulation provided for GDP, GTP and without ligand system by using GROMACS 3.3.2. The result was observed from visualization point of view, potential energy, RMSD and RMSF factors. MD simulation revealed that switch regions moved more flexible than other regions in the structure and tended to move away from nucleotide binding site, distinct from the movements of Ras switches which had shown interactions occurred within y­phosphate and both switches."