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1.
J Biomol Struct Dyn ; 41(23): 13595-13604, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37010992

RESUMO

HDAC protein is associated with hepatocellular carcinoma. Different medicinal plants were selected for this study to analyze the inhibitory efficacy against the target protein, HDAC. Using virtual screening, we filtered out the best compounds, and molecular docking (XP) was carried out for the top compounds which filtered out. The molecular docking results showed that the title compound (2-methoxy-4-prop-2-enylphenyl) N-(2-methoxy-4-nitrophenyl) carbamate (MEMNC) has the highest docking score of about -7.7 kcal/mol against the targeted protein histone deacetylase (HDAC) compared with the other selected phytocompounds. From the molecular dynamics analysis, the RMSD and RMSF plots depicted the overall stability of the protein-ligand complex. Toxicity properties show the acceptable range of various kinds of toxicity that were predicted using the ProTox-II server. In addition, DFT quantum chemical and physicochemical properties of the MEMNC molecule were reported. Initially, the molecular structure of the MEMNC molecule was optimized and harmonic vibrational frequencies were calculated using DFT/B3LYP method with a cc-pVTZ basis set using Gaussian 09 program. The calculated vibrational wavenumber values were assigned based on Potential Energy Distribution calculations using the VEDA 4.0 program and correlated well with the previous literature values. The molecule has bioactivity as a result of intramolecular charge transfer interactions, as demonstrated by frontier molecular orbital analysis. Molecular electrostatic potential surface and Mulliken atomic charge distribution analyses validate the reactive sites of the molecule. Thus, the title compound can be used as a potential inhibitor of HDAC protein, which paves the way for designing novel drugs to treat Hepatocellular carcinoma.Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Carcinoma Hepatocelular/tratamento farmacológico , Carbamatos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Neoplasias Hepáticas/tratamento farmacológico , Teoria Quântica , Análise Espectral Raman
2.
Comput Intell Neurosci ; 2022: 6084044, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082342

RESUMO

In this paper, a deep learning algorithm was proposed to ensure the voice call quality of the cellular communication networks. This proposed model was consecutively monitoring the voice data packets and ensuring the proper message between the transmitter and receiver. The phone sends its unique identification code to the station. The telephone and station maintain a constant radio connection and exchange packets from time to time. The phone can communicate with the station via analog protocol (NMT-450) or digital (DAMPS, GSM). Cellular networks may have base stations of different standards, which allow you to improve network performance and improve its coverage. Cellular networks are different operators connected to each other, as well as a fixed telephone network that allows subscribers of one operator to another to make calls from mobile phones to landlines and from landlines to mobiles. The simulation is conducted in Matlab against different performance metrics, that is, related to the quality of service metric. The results of the simulation show that the proposed method has a higher QoS rate than the existing method over an average of 97.35%.


Assuntos
Telefone Celular , Aprendizado Profundo , Algoritmos
3.
J Colloid Interface Sci ; 579: 347-356, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32610207

RESUMO

Herein, we propose a new highly porous natural carbon material from renewable and inexpensive jujube fruits as a carbon source applied in supercapacitors. The combination of pre-carbonization and chemical activation approaches is employed to product hierarchical porous carbon from natural jujube fruits. The specific surface area of the prepared porous carbon is increased from 85.4 to 1135 m2 g-1 after the completion of NaOH activation at an optimized condition, which is beneficial to enhancing electrochemical performance of supercapacitors. A 3-electrode configuration was utilized to explore the electrochemical ability of porous carbon in 6 M KOH electrolyte. The acquired results demonstrate that porous carbon displays the specific capacitance of 587, 460 and 324 F g-1 at 0.1, 1 and 100 A g-1, respectively, which is confirmed by its admirable capacitance and rate behaviors. The porous carbon also shows a wonderful durability with a capacitance retention of 92.2% after 130,000 cycles at 50 A g-1. Moreover, the assembled symmetrical coin-like supercapacitors with wide potential window of 2.5 V in 1 M Et4NBF4/AN organic electrolyte offer a high energy density of 23.7 Wh kg-1 at 0.629 kW kg-1 with remaining 94% capacitance over 10,000 cycles at 30 A g-1, indicating its practical application prospect. As a result, the present study proves the natural jujube fruits is a promising sustainable carbon source for making more economical and efficient electrode material of high performance supercapacitors.


Assuntos
Carbono , Ziziphus , Capacitância Elétrica , Frutas , Porosidade
4.
3 Biotech ; 6(1): 92, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28330162

RESUMO

The present investigation demonstrates Couroupita guianensis flower buds extract mediated synthesis of stable silver nanoparticles (AgNPs). Instant formation of AgNPs was primarily confirmed by the appearance of yellowish brown colour and characteristic silver SPR band in the UV-visible spectrum. Elemental and crystalline natures of the AgNPs were identified from EDX and XRD pattern, respectively. Spherical morphology and the mono-disparity were revealed from TEM and AFM images. The particle size ranged from 5 to 30 nm and average size of 17 nm was consistent in XRD, TEM and AFM measurements. Possible reduction and stabilizing agents, viz., phenolics, flavonoids and proteins were identified from the characteristic FTIR peaks representing their functional groups. The strong antibacterial activity of synthesized AgNPs against Gram-positive and Gram-negative bacteria exhibited the potential for the formulation of synergistic bactericides by combining antibacterial properties of Couroupita flower buds extract and silver salts for biomedical applications.

5.
Artigo em Inglês | MEDLINE | ID: mdl-22546474

RESUMO

Single crystals of novel organic nonlinear optical material, L-phenylalaninium maleate (LPM) having dimensions up to 10 × 6 × 6 mm(3) were grown by slow evaporation solution growth technique at room temperature. The grown crystals were confirmed by single crystal X-ray diffraction studies and the various functional groups were identified by FT-IR spectroscopic analysis. The optical properties were studied by optical absorption, second harmonic generation (SHG), photoconductivity and photoluminescence (PL) studies and reported for the first time. The optical band gap energy and SHG efficiency were found to be 4.85 eV and 1.5 times higher than KDP crystals. Negative photoconducting nature was confirmed by photoconductivity studies. Photoluminescence studies confirm the suitability of the sample for blue and green radiations. The title compound was also subjected to TG/DTA analysis and dielectric studies. Layer like growth pattern was analyzed by SEM micrograph.


Assuntos
Fenômenos Químicos , Maleatos/química , Dinâmica não Linear , Fenômenos Ópticos , Fenilalanina/análogos & derivados , Absorção , Cristalização , Análise Diferencial Térmica , Condutividade Elétrica , Luminescência , Microscopia Eletrônica de Varredura , Fenilalanina/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
6.
Toxicol In Vitro ; 16(6): 675-82, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12423650

RESUMO

Understanding the effects of prooxidants on mammalian testis either in vitro or in vivo is important, since recent evidence shows that oxidative stress can play a vital role in the etiology of male infertility. In this investigation, we have examined the oxidative stress response of adult rat testis in vitro as induced by model prooxidants (tert-butyl hydroperoxide (t-bHP) and cumene hydroperoxide (cHP) deploying two models-testicular cell suspensions (TCS) and testicular explants (TE). Significant induction of oxidative stress was observed in both models as evidenced by increased thiobarbituric acid reactive substances (TBARS) levels on incubation with hydroperoxides. The response was both concentration and time dependent. At the highest concentration (200 microM), both hydroperoxides induced a 100% increase in the TE model, compared with a dramatic (380-560%) increase in the TCS model during a 30-min incubation. Further evidence of oxidative stress such as reduction in the GSH levels and alterations in the activity of antioxidant enzymes (catalase and glutathione peroxidase) were also obtained in the TE model. In the TE model, radical scavengers, namely thiourea, urea and mannitol, as well as antioxidants such as glutathione and catalase inhibited the t-bHP-induced lipid peroxidation response to varying degree. A similar degree of protection was also evident with known antioxidants such as ascorbic acid, butylated hydroxyanisole and butylated hydroxytoluene in the TE model. Further co-incubation of TE either with mercaptosuccinate (a potent glutathione peroxidase inhibitor) or 3-aminotriazole (an irreversible catalase inhibitor) resulted in a marked increase in t-bHP-induced lipid peroxidation, clearly suggesting the importance of both of these enzymic antioxidants in rat testis in vitro. These data suggest that the TE model may be further utilized to screen antioxidants in vitro and also investigate the prooxidant potency of xenobiotics in testicular cells.


Assuntos
Oxidantes/farmacologia , Estresse Oxidativo , terc-Butil Hidroperóxido/farmacologia , Animais , Técnicas de Cultura de Células , Avaliação Pré-Clínica de Medicamentos , Masculino , Ratos , Ratos Wistar , Testículo/citologia
7.
Toxicol Lett ; 132(1): 27-36, 2002 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-12084617

RESUMO

Acrolein, an alpha,beta-unsaturated aldehyde, is by far the strongest electrophile present in cigarette smoke which is involved in several lung pathophysiological conditions. Acrolein depletes glutathione and creates thiol imbalance. Acrolein due to thiol imbalance as well as covalent modification of cysteine is known to inhibit the activity of redox sensitive transcription factors such as NF-kappaB and AP-1. Exposure of human type II lung epithelial (A549) cells to non-lethal dose of acrolein (150 fmol/cell for 1 h) depletes 80% of intracellular glutathione and increases the transcription of gamma-glutamylcysteine synthetase (gamma-GCS) at 6-12 h post-treatment, which helps in replenishing the glutathione to normal level. Acrolein treatment activates transcription of phase II genes in general, as indicated by an increase in mRNA for NAD (P) H:quinone oxidoreductase (NQO1). Western blot analysis revealed the increased level of the transcription factor, Nrf2 in the nuclear extract from acrolein treated cells. Electrophoretic mobility shift assay shows increased binding of nuclear proteins to human antioxidant response element (ARE) consensus sequence after treatment with acrolein. The involvement of Nrf2 in ARE mediated transcriptional activation in response to acrolein exposure has been confirmed by human NQO1-ARE reporter assay. The ability of acrolein to transcriptionaly activate genes responsible for phase II enzymes may form the basis of resistance against cell death and can have implications in cigarette smoke related lung carcinogenesis.


Assuntos
Acroleína/farmacologia , Proteínas de Ligação a DNA/genética , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Pulmão/metabolismo , Transativadores/genética , Antioxidantes/farmacologia , Western Blotting , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Hibridização In Situ , Luciferases/genética , Fator 2 Relacionado a NF-E2 , Elementos de Resposta/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/efeitos dos fármacos
8.
Mutat Res ; 513(1-2): 103-11, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719095

RESUMO

Our previous work has shown that prooxidant treatment has the propensity to induce male-mediated dominant lethal (DL) type mutations in mice. The present investigation is aimed to understand the effect of oxidative stress (OS) on DNA damage in testis, epididymal sperms and its propensity to induce sperm head abnormalities as well as its implications on male fertility in mice. Initially, employing two organic hydroperoxides, (t-butyl hydroperoxide, t-bHP and cumene hydroperoxide, cHP) as model prooxidants, induction of oxidative stress was ascertained following single/multiple sublethal doses. Further, the multiple exposure model was utilized to characterize effects on testicular weights, histoarchitecture, caudal sperm counts, lipid peroxidation, DNA damage and frequency of abnormal sperms. Single sublethal doses (1/20, 1/10 and 1/5 LD(50)) of t-bHP and cHP administered (i.p.) to adult mice resulted in only a marginal increase (20% at the highest dosage) in testicular MDA levels. However, multiple doses (1/10 and 1/5 LD(50) per day for 5 days) induced marked OS in testis and epididymal sperms as evidenced by a marked increase in lipid peroxidation at 24h after the last dose. This was associated with significant increase in the DNA damage (FADU assay) in the testicular tissue. While caudal sperm counts determined at all sampling weeks showed no treatment related alterations, analysis for head abnormalities revealed nearly 2-3-fold increase in the percent abnormal sperms among the hydroperoxide treated mice during the first 3 weeks. Furthermore, mating of prooxidant treated males sequentially for a period of 5 weeks with untreated females resulted in a significant reduction in average pup number per litter during the first 3 weeks. These results suggest that oxidative stress in testicular milieu is associated with DNA damage and produces higher frequency of abnormal sperms with significant effect on male fertility.


Assuntos
Dano ao DNA , Infertilidade Masculina/etiologia , Estresse Oxidativo , Espermatozoides/patologia , Testículo/metabolismo , Animais , Feminino , Peroxidação de Lipídeos , Masculino , Camundongos , Contagem de Espermatozoides
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