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1.
Neurotox Res ; 41(6): 698-707, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37847429

RESUMO

Alzheimer's disease contributes to 60-70% of all dementia cases in the general population. Belonging to the BIN1/amphiphysin/RVS167 (BAR) superfamily, the bridging integrator (BIN1) has been identified to impact two major pathological hallmarks in Alzheimer's disease (AD), i.e., amyloid beta (Aß) and tau accumulation. Aß accumulation is found to increase by BIN1 knockdown in cortical neurons in late-onset AD, due to BACE1 accumulation at enlarged early endosomes. Two BIN1 mutants, KR and PL, were identified to exhibit Aß accumulation. Furthermore, BIN1 deficiency by BIN1-related polymorphisms impairs the interaction with tau, thus elevating tau phosphorylation, altering synapse structure and tau function. Even though the precise role of BIN1 in the neuronal tissue needs further investigation, the authors aim to throw light on the potential of BIN1 and unfold its implications on tau and Aß pathology, to aid AD researchers across the globe to examine BIN1, as an appropriate target gene for disease management.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Proteínas tau/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
2.
iScience ; 25(9): 104831, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36039304

RESUMO

Range anxiety is a primary concern among present-day electric vehicle (EV) owners, which could be curtailed by maximizing the driving range per charge or reducing the charging time of the lithium-ion battery (LIB) pack. Maximizing the driving range is a multifaceted task as charging-discharging the LIB up to 100% of its nominal capacity is limited by the cell chemistry (voltage window) and cell operating conditions. Our studies on commercial LiFePO4/graphite cells show that a cycle life of 4320 is achieved at 4C rate with 80% SOC-100% DOD combination (12 min charging time), which is the highest among the works reported with this cell chemistry. Complete utilization of electrodes' lithium during cycling resulted in the lowest cycle life of 956. This study demonstrates LIB charging-discharging protocol enabling longer driving range with quicker charging times. Besides, it might endow promising possibilities of future EV LIB packs with reduced size/weight and high safety.

3.
J Mol Struct ; 1266: 133483, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35692554

RESUMO

A novel drug to treat SARS-CoV-2 infections and hydroxyl chloroquine analogue, (E)-2,6-bis(4-chlorophenyl)-3-methyl-4-(2-(2,4,6-trichlorophenyl)hydrazono)piperidine (BCMTP) compound has been synthesized in one pot reaction. The novel compound BCMTP has been characterized by FT-IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction patterns. Crystal packing is stabilized by C8-H8A•••Cl10i, C41-H41•••Cl1ii and N1-H1A•••Cl6iii intermolecular hydrogen bonds. From the geometrical parameters, it is observed that the piperidine ring adopts chair conformation. Hirshfeld surface analysis was carried out to quantify the interactions and an interaction energy analysis was done to study the interactions between pairs of molecules. The geometrical structure was optimized by density functional theory (DFT) method at B3LYP/6-31G (d, p) as the basic set. The smaller binding energy value provides the higher reactivity of BCMTP compound than hydroxyl chloroquine and was corrected by high electrophilic and low nucleophilic reactions. The stability and charge delocalization of the molecule were also considered by natural bond orbital (NBO) analysis. The HOMO-LUMO energies describe the charge transfer which takes place within the molecule. Molecular electrostatic potential has also been analysed. Molecular docking studies are implemented to analyse the binding energy of the BCMTP compound against standard drugs such as the crystal structure of ADP ribose phosphatase of NSP3 from SARS-CoV-2 in complex with MES and SARS-CoV-2 main protease with an unliganded active site (2019-nCoV, corona virus disease 2019, COVID-19) and found to be considered having better antiviral agents. Molecular dynamics simulation was performed for COVID-19 main protease (Mpro: 6WCF/6Y84) to understand the elements governing the inhibitory effect and the stability of interaction under dynamic conditions.

4.
Mater Today Proc ; 55: 327-329, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34381695

RESUMO

Recently, the outbreak of COVID-19 caused serious global health issues and the world is facing a crisis of antiviral resistance. To overcome the crisis, we reviewed the existing therapies that could be an alternative and effective treatment for COVID-19. Therapies such as ozone, laser, UV radiation and radiation therapy are discussed and the mechanism of killing is elaborated. In conclusion, the ozone, laser and radiation therapy could be considered as an alternative therapy in extirpating the coronavirus from bloodstreams and the challenges in bringing these therapies to clinical trials.

5.
Artigo em Inglês | MEDLINE | ID: mdl-26151437

RESUMO

(E)-(4-(2-(benzo[d]thiazol-2-yl)hydrazono)-3-methyl-2,6-diphenylpiperidin-1-yl)(phenyl)methanone [EPHDPM] and its derivatives were synthesized and characterized by FT-IR, (1)H NMR, (13)C NMR and elemental analysis. The target compound [EPHDPM] was computed using density functional theory (DFT) method. The ground-state molecular geometry and vibrational frequencies were calculated by using B3LYP/6-31G (d,p) level of theory. The experimentally observed FT-IR and FT-Raman bands were assigned to different normal modes of the molecule. The stability and charge delocalization of the molecule were also studied by natural bond orbital (NBO) analysis. The HOMO-LUMO energies describe the charge transfer takes place within the molecule. Molecular electrostatic potential has been analyzed. The reported EPHDPM molecule used as a potential NLO material since it has high µß0 value. Thermodynamic parameter like entropy and enthalpy are calculated and these values are increased with increasing the temperature due to the enhancement of vibrational intensities.


Assuntos
Piperidinas/química , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman/métodos , Tiazóis/química , Entropia , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Eletricidade Estática , Termodinâmica , Vibração
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 108-18, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25554959

RESUMO

A new series of 2,6-diaryl-1-(prop-2-yn-1-yl)piperidin-4-one oximes (17-24) were designed and synthesized from 2,6-diarylpiperidin-4-one oximes (9-16) with propargyl bromide. Unambiguous structural elucidation has been carried out by investigating IR, NMR ((1)H, (13)C, (1)H-(1)H COSY and HSQC), mass spectral techniques and theoretical (DFT) calculations. Further, crystal structure of compound 17 was evaluated by single crystal X-ray diffraction analysis. Single crystal X-ray structural analysis of compound 17 evidenced that the configuration about CN double bond is syn to C-5 carbon (E-form). The existence of chair conformation was further confirmed by theoretical DFT calculation. All the synthesized compounds were screened for in vitro antimicrobial activity against a panel of selected bacterial and fungal strains using Ciprofloxacin and Ketoconazole as standards. The minimum inhibition concentration (MIC) results revealed that most of the 2,6-diaryl-1-(prop-2-yn-1-yl)piperidin-4-one oximes (17, 19, 20 and 23) exhibited better activity against the selected bacterial and fungal strains.


Assuntos
Modelos Moleculares , Oximas/síntese química , Oximas/farmacologia , Piperidonas/síntese química , Piperidonas/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalografia por Raios X , Elétrons , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Oximas/química , Piperidonas/química , Espectroscopia de Prótons por Ressonância Magnética , Teoria Quântica , Eletricidade Estática
7.
Sci Rep ; 4: 4049, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24514043

RESUMO

Graphene has proved its significant role as a reinforcement material in improving the strength of polymers as well as metal matrix composites due to its excellent mechanical properties. In addition, graphene is also shown to block dislocation motion in a nanolayered metal-graphene composites resulting in ultra high strength. In the present paper, we demonstrate the synthesis of very hard Cu-Graphene composite foils by a simple, scalable and economical pulse reverse electrodeposition method with a well designed pulse profile. Optimization of pulse parameters and current density resulted in composite foils with well dispersed graphene, exhibiting a high hardness of ~2.5 GPa and an increased elastic modulus of ~137 GPa while exhibiting an electrical conductivity comparable to that of pure Cu. The pulse parameters are designed in such a way to have finer grain size of Cu matrix as well as uniform dispersion of graphene throughout the matrix, contributing to high hardness and modulus. Annealing of these nanocomposite foils at 300°C, neither causes grain growth of the Cu matrix nor deteriorates the mechanical properties, indicating the role of graphene as an excellent reinforcement material as well as a grain growth inhibitor.

8.
ScientificWorldJournal ; 2012: 127326, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22619580

RESUMO

Different amounts of Ni-doped TiO(2) (Ni = 0.1 to 10%) powders and thin films were prepared by following a conventional coprecipitation and sol-gel dip coating techniques, respectively, at 400 to 800°C, and were thoroughly characterized by means of XRD, FT-IR, FT-Raman, DRS, UV-visible, BET surface area, zeta potential, flat band potential, and photocurrent measurement techniques. Photocatalytic abilities of Ni-doped TiO(2) powders were evaluated by means of methylene blue (MB) degradation reaction under simulated solar light. Characterization results suggest that as a dopant, Ni stabilizes TiO(2) in the form of anatase phase, reduces its bandgap energy, and adjusts its flat band potentials such that this material can be employed for photoelectrochemical (PEC) oxidation of water reaction. The photocatalytic activity and photocurrent ability of TiO(2) have been enhanced by doping of Ni in TiO(2). The kinetic studies revealed that the MB degradation reaction follows the Langmuir-Hinshelwood first-order reaction relationship.


Assuntos
Níquel/química , Titânio/química , Catálise , Técnicas Eletroquímicas , Processos Fotoquímicos , Difração de Raios X
9.
Org Lett ; 8(4): 605-8, 2006 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-16468722

RESUMO

[reaction: see text] Synthesis, characterization, and electrochemistry of linear and tribranched polyphenylacetylenes having redox-active ferrocene and/or (arene)chromiumtricarbonyl as end groups are reported in this study. The methodology adopts polymerization of phenylacetylene by a metathesis pathway, initiated by W(CO)(6) when photolyzed. A distance-dependent electronic communication between the metal centers is demonstrated in these polymers by means of cyclic voltammetry.

10.
J Environ Biol ; 22(1): 11-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11480344

RESUMO

Aqueous leaf extracts of two plants namely Gnidia glauca Gilg. and Toddalia asiatica Lam., have been screened for their antifeedant activity against the sixth instar larvae of Helicoverpa armigera (Hbn) by applying the aqueous leaf extracts at various concentrations viz., 0.2, 0.4, 0.6, 0.8 and 1.0 percent on young tomato leaves. The larval mortality of more than 50 percent at higher concentrations (0.8 and 1.0 percent) was observed in the aqueous extracts. Among the two aqueous leaf extracts tested, T. asiatica was found to show higher rate of mortality (86.1%) at 1.0 percent concentration. A reduction in the rate of food consumption and growth was observed in the larvae of H. armigera after 48 hours of treatments in both the aqueous extracts. Since this insect pest species have developed resistance and resurgence to synthetic insecticides, the only alternate is the usage of bio-pesticides for they are eco-friendly, pollution free and easily degradable.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Rosales , Animais , Larva/efeitos dos fármacos , Solanum lycopersicum , Extratos Vegetais/farmacologia , Folhas de Planta
11.
Org Lett ; 3(3): 389-92, 2001 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-11428021

RESUMO

[figure: see text] Monomer (R,R)-3-aza-3-(p-vinylbenzyl)-1,5-diphenyl-1,5-dihydroxypentane (2) when polymerized with styrene and divinylbenzene affords polymers, onto which lithium and aluminum are incorporated via reaction with lithium aluminum hydride. The resulting insoluble polymers containing chiral lithium and aluminum active centers are quite effective for asymmetric Michael addition of nitro compounds, thiols, and amines. The optimized reaction conditions yield Michael adducts in good yield with high enantiomeric excesses.

12.
Org Lett ; 3(13): 1973-6, 2001 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-11418027

RESUMO

[reaction: see text] (R,R)-3-Aza-3-benzyl-1,5-dihydroxy-1,5-diphenylpentane (1) ligated Ti(IV) complex (1-TiCl(2)) is used as a chiral Lewis acid catalyst for promoting asymmetric IED Diels-Alder reaction between electron-rich dienophiles and electron-poor dienes. Here we introduce a facile route for the synthesis of asymmetric tetrahydroquinoline derivatives using the above-mentioned chiral catalyst reagent in the presence of 4 A molecular sieves. The reactions proceed with moderate yields and at times high enantioselectivty.


Assuntos
Quinolinas/síntese química , Conformação Molecular , Quinolinas/química , Difração de Raios X
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