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1.
Int J Biol Macromol ; 253(Pt 5): 127182, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37793515

RESUMO

Encapsulation of DNA vaccines onto carriers enhances the immunogenicity of an antigen. Specifically, biodegradable polymers offer sustained release of vaccines which is crucial for any targeted delivery approach. Poly (lactic-co-glycolic) acid (PLGA) microspheres were used to load a DNA vaccine having a targeted gene of outer membrane protein (OMP) of Aeromonas hydrophila to clone and construct a DNA vaccine using a eukaryotic expression vector system (pVAX1-OMP DNA) and delivery in Carassius auratus against A. hydrophila infection. PLGA microspheres were prepared by emulsion technique oil-in-water and characterized by a High-Resolution Scanning Electron Microscope (HR-SEM). The results of PLGA-pVAX1-OMP DNA microspheres shows that average of 100-150 µm particle size and a loading efficiency (LE) of 68.8 %. Results indicate that C. auratus fed with PLGA-pVAX1-OMP DNA microspheres revealed a significant improvement in innate immune response, which includes, myeloperoxidase activity, respiratory burst and total immunoglobulin level compared with control group fish. The immune-related gene, IL1ß, IL10, TGF, c-type, and g-type lysozyme also showed significantly higher expression after immunization. Furthermore, dietary supplementation of the PLGA-pVAX1-OMP DNA (G III) group exhibited a significantly higher survival rate (78 %) than the control group of fish. These results help us to understand the of mechanism of DNA vaccine administrated feed through PLGA nanoparticles resistance to infection by regulating systemic and innate immunity in Carassius auratus.


Assuntos
Aeromonas hydrophila , Vacinas de DNA , Animais , Ácido Poliglicólico , Ácido Láctico , Glicóis , Microesferas , Carpa Dourada , DNA
2.
Micron ; 172: 103486, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37262930

RESUMO

Recent advancements in the field of nanotechnology have enabled targeted delivery of drug agents in vivo with minimal side effects. The use of nanoparticles for bio-imaging has revolutionized the field of nanomedicine by enabling non-invasive targeting and selective delivery of active drug moieties in vivo. Various inorganic nanomaterials like mesoporous silica nanoparticles, gold nanoparticles, magnetite nanoparticles graphene-based nanomaterials etc., have been created for multimodal therapies with varied multi-imaging modalities. These nanomaterials enable us to overcome the disadvantages of conventional imaging contrast agents (organic dyes) such as lack of stability in vitro and in vivo, high reactivity, low-quantum yield and poor photo stability. Inorganic nanomaterials can be easily fabricated, functionalised and modified as per requirements. Recently, advancements in synthesis techniques, such as the ability to generate molecules and construct supramolecular structures for specific functionalities, have boosted the usage of engineered nanomaterials. Their intrinsic physicochemical properties are unique and they possess excellent biocompatibility. Inorganic nanomaterial research has developed as the most actively booming research fields in biotechnology and biomedicine. Inorganic nanomaterials like gold nanoparticles, magnetic nanoparticles, mesoporous silica nanoparticles, graphene-based nanomaterials and quantum dots have shown excellent use in bioimaging, targeted drug delivery and cancer therapies. Biocompatibility of nanomaterials is an important aspect for the evolution of nanomaterials in the bench to bedside transition. The conduction of thorough and meticulous study for safety and efficacy in well-designed clinical trials is absolutely necessary to determine the functional and structural relationship between the engineered nanomaterial and its toxicity. In this article an attempt is made to throw some light on the current scenario and developments made in the field of nanomaterials in bioimaging.


Assuntos
Grafite , Nanopartículas de Magnetita , Nanopartículas , Grafite/química , Ouro/química , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Dióxido de Silício/química
3.
Adv Protein Chem Struct Biol ; 135: 57-96, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37061341

RESUMO

The regulatory proteins, cyclins, and cyclin-dependent kinases (CDKs) control the cell cycle progression. CDK4 gene mutations are associated with certain cancers such as melanoma, breast cancer, and rhabdomyosarcoma. Therefore, understanding the mechanisms of cell cycle control and cell proliferation is essential in developing cancer treatment regimens. In this study, we obtained cancer-causing CDK4 mutations from the COSMIC database and subjected them to a series of in silico analyses to identify the most significant mutations. An overall of 238 mutations (119 missense mutations) retrieved from the COSMIC database were investigated for the pathogenic and destabilizing properties using the PredictSNP and iStable algorithms. Further, the amino acid position of the most pathogenic and destabilizing mutations were analyzed to understand the nature of amino acid conservation across the species during the evolution. We observed that the missense mutations G201R and G201D were more significant and the Glycine at position 201 was found to highly conserved. These significant mutations were subjected to molecular dynamics simulation analysis to understand the protein's structural changes. The results from molecular dynamics simulations revealed that both G201R and G201D of CDK4 are capable of altering the protein's native form. On comparison among the most significant mutations, G201R disrupted the protein structure higher than the protein with G201D.


Assuntos
Mutação de Sentido Incorreto , Neoplasias , Humanos , Quinase 4 Dependente de Ciclina/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Aminoácidos
4.
Nanomedicine ; 47: 102613, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36252911

RESUMO

The current challenges in cancer treatment using conventional therapies have made the emergence of nanotechnology with more advancements. The exponential growth of nanoscience has drawn to develop nanomaterials (NMs) with therapeutic activities. NMs have enormous potential in cancer treatment by altering the drug toxicity profile. Nanoparticles (NPs) with enhanced surface characteristics can diffuse more easily inside tumor cells, thus delivering an optimal concentration of drugs at tumor site while reducing the toxicity. Cancer cells can be targeted with greater affinity by utilizing NMs with tumor specific constituents. Furthermore, it bypasses the bottlenecks of indiscriminate biodistribution of the antitumor agent and high administration dosage. Here, we focus on the recent advances on the use of various nanomaterials for cancer treatment, including targeting cancer cell surfaces, tumor microenvironment (TME), organelles, and their mechanism of action. The paradigm shift in cancer management is achieved through the implementation of anticancer drug delivery using nano routes.


Assuntos
Nanotecnologia , Distribuição Tecidual
5.
Nanoscale ; 14(30): 10630-10647, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35842941

RESUMO

Nanoarchitectonics relies on the fabrication of materials at the atomic/molecular level to achieve the desired shape and function. Significant advances have been made in understanding the characteristics and spatial assemblies that contribute to material performance. Biomaterials undergo several changes when presented with various environmental cues. The ability to overcome such challenges, maintaining the integrity and effective functioning of native properties, can be regarded as a characteristic of a successful biomaterial. Control over the shape and efficacy of target materials can be tailored via various processes, like self-assembly, supramolecular chemistry, atomic/molecular manipulation, etc. Interplay between the physicochemical properties of materials and biomolecule recognition sites defines the structural rigidity in hierarchical structures. Materials including polymers, metal nanoparticles, nucleic acid systems, metal-organic frameworks, and carbon-based nanostructures can be viewed as promising prospects for developing biocompatible systems. This review discusses recent advances relating to such biomaterials for life science applications, where nanoarchitectonics plays a decisive role either directly or indirectly.


Assuntos
Disciplinas das Ciências Biológicas , Estruturas Metalorgânicas , Nanoestruturas , Materiais Biocompatíveis/química , Nanoestruturas/química , Polímeros/química
6.
Environ Res ; 212(Pt B): 113202, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35398077

RESUMO

The presence and longevity of nanomaterials in the ecosystem, as well as their properties, account for environmental toxicity. When nanomaterials in terrestrial and aquatic systems are exposed to the prevailing environmental conditions, they undergo various transformations such as dissociation, dissolution, and aggregation, which affects the food chain. The toxicity of nanomaterials is influenced by a variety of factors, including environmental factors and its physico-chemical characteristics. Bioaccumulation, biotransformation, and biomagnification are the mechanisms that have been identified for determining the fate of nanomaterials. The route taken by nanomaterials to reach living cells provides us with information about their toxicity profile. This review discusses the recent advances in the transport, transformation, and fate of nanomaterials after they are released into the environment. The review also discusses how nanoparticles affect lower trophic organisms through direct contact, the impact of nanoparticles on higher trophic organisms, and the possible options for remediation.


Assuntos
Nanopartículas , Nanoestruturas , Poluentes Químicos da Água , Bioacumulação , Ecossistema , Cadeia Alimentar , Nanopartículas/toxicidade , Nanoestruturas/química , Nanoestruturas/toxicidade , Poluentes Químicos da Água/análise
7.
Enzyme Microb Technol ; 95: 100-106, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27866603

RESUMO

Biosynthesis of gold nanoparticles (AuNPs) using Sargassum swartzii and its anti-diabetic effect were studied using male wistar Albino rats. Formation of AuNPs were confirmed by UV-vis spectroscopy, Fourier transformed infrared (FTIR) spectroscopy, High-Resolution transmission electron microscopy (HR-TEM) and X-ray diffraction (XRD). Fasting blood glucose levels, serum insulin, hemoglobin and glycosylated hemoglobin levels in diabetic treated rats with AuNPs were significantly decreased compared to the control group. The results of the blood glucose level and serum insulin levels indicated that AuNPs could significantly improve the insulin resistance and glucose level in diabetic rats. AuNPs also shows reduction in anti-inflammation, tumor necrosis factor-alpha, interleukin-6 and high-sensitive C-reactive protein in diabetic rats. The data showed that AuNPs synthesized using S. swartzii exerted antidiabetic effect, accordingly improve pancreas, liver and kidney damage caused by alloxan induced diabetic rats.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Sargassum/metabolismo , Animais , Biotecnologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Química Verde , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Masculino , Nanotecnologia , Ratos , Ratos Wistar
8.
Int J Biol Macromol ; 93(Pt A): 1030-1040, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27637452

RESUMO

Pectin and its several modified forms have shown remarkable impact in therapeutic use against various cancers. In the present study, pectin, an anionic polysaccharide isolated from Musa paradisiaca is employed for the synthesis of gold nanoparticles at ambient temperature conditions. The synthesized nanoparticles were characterized using microscopic and spectroscopic studies and its anti-cancer potential was evaluated in mammary adenocarcinoma cell lines MCF-7 and MDA-MB-231. Apoptosis induction was evident from increase in sub-G1 population studied using flow cytometry analysis. DNA damage followed by cell death in pectin mediated gold nanoparticles (p-GNPs) treated cells was confirmed by Comet assay. Uptake of p-GNPs by cancer cells (MCF-7 and MDA-MB-231) was analyzed using FE-SEM which revealed the presence of p-GNPs as aggregates over the surface of cells with loss in cellular integrity compared to control cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Nanopartículas Metálicas/química , Pectinas/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Ouro/química , Humanos , Células MCF-7 , Tamanho da Partícula , Propriedades de Superfície
9.
Infect Dis Poverty ; 5: 12, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26888469

RESUMO

BACKGROUND: The Ebola virus is highly pathogenic and destructive to humans and other primates. The Ebola virus encodes viral protein 40 (VP40), which is highly expressed and regulates the assembly and release of viral particles in the host cell. Because VP40 plays a prominent role in the life cycle of the Ebola virus, it is considered as a key target for antiviral treatment. However, there is currently no FDA-approved drug for treating Ebola virus infection, resulting in an urgent need to develop effective antiviral inhibitors that display good safety profiles in a short duration. METHODS: This study aimed to screen the effective lead candidate against Ebola infection. First, the lead molecules were filtered based on the docking score. Second, Lipinski rule of five and the other drug likeliness properties are predicted to assess the safety profile of the lead candidates. Finally, molecular dynamics simulations was performed to validate the lead compound. RESULTS: Our results revealed that emodin-8-beta-D-glucoside from the Traditional Chinese Medicine Database (TCMD) represents an active lead candidate that targets the Ebola virus by inhibiting the activity of VP40, and displays good pharmacokinetic properties. CONCLUSION: This report will considerably assist in the development of the competitive and robust antiviral agents against Ebola infection.


Assuntos
Antivirais/farmacologia , Ebolavirus/efeitos dos fármacos , Proteínas Virais/antagonistas & inibidores , Antivirais/química , Avaliação Pré-Clínica de Medicamentos , Ebolavirus/química , Ebolavirus/genética , Ebolavirus/metabolismo , Células HEK293 , Doença pelo Vírus Ebola , Humanos , Simulação de Acoplamento Molecular , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
10.
J Nanosci Nanotechnol ; 15(6): 4052-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26369012

RESUMO

In the present study, gold nanoparticles (AuNPs) were synthesized using leaf extract of Syzygium jambolanum and capping agent has been explored. The synthesized AuNPs have been characterized using UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), high resolution transmission electron microscopy (HRTEM) and atomic force microscopic (AFM) analysis. The AuNPs show intense surface plasmon resonance (SPR) band at 528 nm and were found to be spherical and hexagonal in shape with particle size ranging from 20-30 nm. Transmission electron microscopy and atomic force microscopy were used to analyze the surface morphology of synthesized AuNPs. The capping ligand has been evaluated using matrix assisted laser desorption ionization-mass spectrometry (MALDI-MS) and gas chromatography-mass spectrometry (GC-MS) analysis.


Assuntos
Biotecnologia/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Extratos Vegetais/metabolismo , Syzygium/química , Cromatografia Gasosa-Espectrometria de Massas , Ouro/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 144: 266-72, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25769122

RESUMO

Silver nanoparticles (AgNPs) are synthesized using biological sources due to its high specificity in biomedical applications. Herein, we report the size and shape controlled synthesis of AgNPs using the aqueous extract of blue green alga, Spirulina platensis. Size, shape and elemental composition of AgNPs were characterized using UV-vis spectroscopy, Fluorescence spectroscopy, FT-IR (Fourier Transform-Infrared Spectroscopy), FT-RS (Fourier Transform-Raman Spectroscopy), SEM-EDAX (Scanning Electron Microscopy-Energy Dispersive X-ray analysis) and HR-TEM (High Resolution Transmission Electron Microscopy). AgNPs were stable, well defined and monodispersed (spherical) with an average size of 6 nm. The synthesized AgNPs were tested for its antibacterial potency against isolates obtained from HIV patients.


Assuntos
Antibacterianos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Nanopartículas Metálicas/química , Tamanho da Partícula , Prata/farmacologia , Spirulina/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Análise de Sequência de RNA , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
12.
Mater Sci Eng C Mater Biol Appl ; 47: 351-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25492207

RESUMO

Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet-visible (UV-vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of ~ 5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Cianobactérias/química , Ouro/química , Ouro/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão/métodos , Espectrofotometria Ultravioleta/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos
13.
Colloids Surf B Biointerfaces ; 122: 505-511, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25092583

RESUMO

Development of novel antidiabetic agents using various organic compounds and biomolecules has been in practice for a long time. Recently, nanomaterials are also being used in antidiabetic studies for their unique properties such as small size, biocompatibility and ability to penetrate cell membrane for carrying drugs. Herein, in vivo antidiabetic activity of gold nanoparticles (AuNPs) synthesized using the antidiabetic potent plant Gymnema sylvestre R. Br on wistar albino rats has been evaluated. The formation of AuNPs and their morphology were confirmed using spectroscopic and microscopic analyses, respectively. The treatment of AuNPs has shown significant reduction in blood glucose level on diabetic rats. AuNPs were also tested for its anti-inflammatory effect by estimating the serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and high-sensitive C-reactive protein (CRP).


Assuntos
Ouro/química , Nanopartículas Metálicas , Aloxano , Animais , Diabetes Mellitus Experimental/terapia , Microscopia de Força Atômica , Ratos , Ratos Wistar , Espectrofotometria Ultravioleta
14.
Artigo em Inglês | MEDLINE | ID: mdl-24934968

RESUMO

In this investigation, biological synthesis of gold nanoparticles (AuNPs) using Sargassum swartzii and its cytotoxicity against human cervical carcinoma (HeLa) cells is reported. The biological synthesis involved the reduction of chloroauric acid led to the formation of AuNPs within 5min at 60°C and the formation of AuNPs was confirmed using UV-vis spectrophotometer. The AuNPs were stable; spherical in shape with well-defined dimensions, and the average size of the particle is 35nm. A zeta potential value of -27.6mV revealed synthesized AuNPs were highly stable. The synthesized AuNPs exhibited a dose-dependent cytotoxicity against human cervical carcinoma (HeLa) cells. Furthermore, induction of apoptosis was measured by DAPI (4',6-Diamidino-2-phenylindole dihydrochloride) staining.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ouro/química , Ouro/farmacologia , Nanopartículas/química , Sargassum/química , Neoplasias do Colo do Útero/tratamento farmacológico , Apoptose/efeitos dos fármacos , Colo do Útero/efeitos dos fármacos , Colo do Útero/patologia , Feminino , Química Verde , Células HeLa , Humanos , Nanopartículas/ultraestrutura , Neoplasias do Colo do Útero/patologia
15.
Cell Biochem Biophys ; 70(2): 975-82, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24807842

RESUMO

M2 proton channel is the target for treating the patients who ere suffering from influenza A infection, which facilitates the spread of virions. Amantadine and rimantadine are adamantadine-based drugs, which target M2 proton channel and inhibit the viral replication. Preferably, rimantadine drug is used more than amantadine because of its fewer side effects. However, S31N mutation in the M2 proton channel was highly resistant to the rimantadine drug. Therefore, in the present study, we focused to understand the drug-resistance mechanism of S31N mutation with the aid of molecular docking and dynamics approach. The docking analysis undoubtedly indicates that affinity for rimantadine with mutant-type M2 proton channel is significantly lesser than the native-type M2 proton channel. In addition, RMSD, RMSF, and principal component analysis suggested that the mutation shows increased flexibility. Furthermore, the intermolecular hydrogen bonds analysis showed that there is a complete loss of hydrogen bonds in the mutant complex. On the whole, we conclude that the intermolecular contact was maintained by D-44, a key residue for stable binding of rimantadine. These findings are certainly helpful for better understanding of drug-resistance mechanism and also helpful for designing new drugs for treating influenza infection against drug-resistance target.


Assuntos
Farmacorresistência Viral/genética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutação , Bombas de Próton/genética , Rimantadina/metabolismo , Rimantadina/farmacologia , Antivirais/metabolismo , Antivirais/farmacologia , Cristalografia por Raios X , Conformação Proteica , Estabilidade Proteica , Bombas de Próton/química , Bombas de Próton/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-24211624

RESUMO

Exploitation of advancements in antimicrobial agent synthesis assisted by nanomaterials has received considerable attention in the recent years. Based on this, an eco-friendly approach for the synthesis of silver chloride nanoparticles (AgClNPs) using aqueous extract of Sargassum plagiophyllum is emphasized. UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), high resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FESEM) were used to characterize the formation of AgClNPs. X-ray diffraction (XRD) patterns clearly illustrate the presence of AgClNPs. The synthesized AgClNPs were tested for its antibacterial activity and it was found to cause considerable amount of deterioration to bacterial cells, when examined using electron microscope and cell viability analysis.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas/química , Sargassum/química , Compostos de Prata/química , Compostos de Prata/farmacologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Nanopartículas/ultraestrutura , Nanotecnologia
17.
Mol Inform ; 33(8): 559-65, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27486041

RESUMO

Influenza infection continues to be a major problem in many parts of the world. Rimantadine is a first-line drug used to treat the influenza infection by targeting M2 proton channel. However, S31N mutation in M2 proton channel diminishes the efficiency of rimantadine and creates resistance. To address this issue, the present study was aimed to screen the effective lead candidate against drug resistance strain of influenza from DrugBank database. Initially, the lead molecules were filtered using Lipinski rule of five and the drug likeliness property. Subsequently, the data reduction was carried out by employing molecular docking study. Finally, molecular dynamics simulations techniques were performed to validate the lead compound. Most importantly, the -p LD50 of the screened lead molecule was calculated using CORAL software to estimate the Rat oral toxicity. Accordingly, memantine may possibly become a promising lead compound of rimantadine-resistant influenza virus strain.

18.
Cell Biochem Biophys ; 68(2): 291-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23794010

RESUMO

H5N1 is a subtype of the influenza A virus that can cause disease in humans and many other animal species. Oseltamivir (Tamiflu) is a potent and selective antiviral drug employed to fight the flu virus in infected individuals by inhibiting neuraminidase (NA), a flu protein responsible for the release and spread of the progeny virions. However, oseltamivir resistance has become a critical problem. In particular, influenza strains with a R292K NA mutation are highly resistant to the oseltamivir. Though the biological functions of the mutations have previously been characterized, the structural basis behind the reduced catalytic activity and reduced protein level is not clear. In this study, molecular docking and molecular dynamics (MD) approach were employed to investigate the structural and dynamical effects throughout the protein structure and specifically, at the drug-binding pocket. Furthermore, potential of mean force was analyzed using explicit solvent MD simulations with the umbrella sampling method to explore the free energy of binding. It is believed that this study provides valuable guidance for the resistance management of oseltamivir and designing of more potent antiviral inhibitor.


Assuntos
Antivirais/química , Farmacorresistência Viral/genética , Virus da Influenza A Subtipo H5N1/genética , Simulação de Acoplamento Molecular , Neuraminidase/química , Oseltamivir/química , Antivirais/metabolismo , Antivirais/farmacologia , Sítios de Ligação , Virus da Influenza A Subtipo H5N1/metabolismo , Mutação , Neuraminidase/genética , Neuraminidase/metabolismo , Oseltamivir/metabolismo , Oseltamivir/farmacologia , Estrutura Terciária de Proteína , Termodinâmica
19.
Colloids Surf B Biointerfaces ; 111: 764-8, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23871522

RESUMO

Materials with enhanced physical and biological properties have been used for biomedical applications and can be developed by functionalizing them using various components. Hydroxyapatite (HAP), among other available synthetic material, serves as one of the best tools in orthopaedics and ceramic coatings. The porous structure of HAP helps in bone cell regeneration, chemical integration of bone and also favours the interaction between bone and tissues. Herein, we have demonstrated a simple procedure for the synthesis of HAP using low molecular weight heparin (LMWH), a structural analogue of bone heparan sulphate proteoglycan. The presence of small sized HAP plates with well-defined structures was revealed using electron microscopic analysis. The phase purity of the synthesized HAP was evaluated using X-ray diffraction pattern obtained before and after immersion in simulated body fluid (SBF).


Assuntos
Durapatita/síntese química , Heparina de Baixo Peso Molecular/química , Temperatura , Água/química , Durapatita/química , Pós , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
20.
Cell Biochem Biophys ; 66(3): 657-69, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23306969

RESUMO

The neuraminidase (NA) of the influenza virus is the target of antiviral drug, oseltamivir. Recently, cases were reported that influenza virus becoming resistant to oseltamivir, necessitating the development of new long-acting antiviral compounds. In this report, a novel class of lead molecule with potential NA inhibitory activity was identified using a combination of virtual screening (VS), molecular docking, and molecular dynamic approach. The PubChem database was used to perform the VS analysis by employing oseltamivir as query. Subsequently, the data reduction was carried out by employing molecular docking study. Furthermore, the screened lead molecules were analyzed with respect to the Lipinski rule of five, drug-likeness, toxicity profiles, and other physico-chemical properties of drugs by suitable software program. Final screening was carried out by normal mode analysis and molecular dynamic simulation approach. The result indicates that CID 25145634, deuterium-enriched oseltamivir, become a promising lead compound and be effective in treating oseltamivir sensitive as well as resistant influenza virus strains.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/enzimologia , Neuraminidase/antagonistas & inibidores , Interface Usuário-Computador , Antivirais/metabolismo , Antivirais/toxicidade , Disponibilidade Biológica , Fenômenos Químicos , Bases de Dados de Produtos Farmacêuticos , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/toxicidade , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neuraminidase/química , Neuraminidase/metabolismo , Conformação Proteica
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