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1.
Angew Chem Int Ed Engl ; 63(17): e202316551, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38411372

RESUMO

Single-entity electrochemistry is a powerful tool that enables the study of electrochemical processes at interfaces and provides insights into the intrinsic chemical and structural heterogeneities of individual entities. Signal processing is a critical aspect of single-entity electrochemical measurements and can be used for data recognition, classification, and interpretation. In this review, we summarize the recent five-year advances in signal processing techniques for single-entity electrochemistry and highlight their importance in obtaining high-quality data and extracting effective features from electrochemical signals, which are generally applicable in single-entity electrochemistry. Moreover, we shed light on electrochemical noise analysis to obtain single-molecule frequency fingerprint spectra that can provide rich information about the ion networks at the interface. By incorporating advanced data analysis tools and artificial intelligence algorithms, single-entity electrochemical measurements would revolutionize the field of single-entity analysis, leading to new fundamental discoveries.

2.
Heliyon ; 9(6): e16866, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484294

RESUMO

Senescence is a natural phenomenon of growing old. It accelerates under certain conditions like diabetes mellitus resulting in early decline of bodily functions, which can be avoided by many claimed functional foods. The present study aims to investigate the anti-aging ability of Fenugreek seeds (Trigonellafoenum-graecum); a common ingredient of Indo-Pak cuisines. Briefly, the Fenugreek seeds extract (FgSE) in concentrationsof0.1, 0.5 and 1 mg/ml inhibited the formation of Advanced Glycation End products (AGEs) and fructosamine adducts in Bovine serum albumin (BSA)/fructose model in vitro. The BSA conformational analysis via Circular Dichorism and Congo red assays showed that it preserves secondary structure of BSA in aforementioned model. Although mechanistic studies revealed insignificant lysine blocking ability of Fenugreek by OPA assay, however carbonyl entrapping was found to be 24%, 34% and 42% at 0.1, 0.5 and 1 mg/ml, respectively. In vivo model of High Fructose diet (HFD) induced glycation, FgSE treatment in doses of 10, 25 & 50 mg/kg markedly improved Escape latency (p < 0.01) and preserved cognition in Morris Water Maze. Our data further exhibits significant decrease of CML (Nε-carboxymethyl lysine) levels in serum and hippocampus byFgSE treatment in comparison with HFD group. Therefore, we deduced that FgSE prevents glycation-induced memory decline via entrapping the reactive carbonyl intermediates, formed during production of AGEs. Hence, as a promising functional food it slows down the harmful process of glycation and aging associated morbidities.

3.
Technol Cancer Res Treat ; 21: 15330338221076669, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35229683

RESUMO

Cancer is the most complex and leading cause of fatality worldwide. Despite meritorious research in the field of cancer, it is still a substantial threat to human life. In this article, we address a question on the present strategies and manifest the importance of critical biomarkers for cancer screening and early diagnosis before the symptoms appear. However, this goal can only be achieved if scientists will focus on ultra-sensitive detection techniques such as "Nanopore." Nanopore sensing is a simple and rapid single-molecule detection technique that can detect multiple cancer biomarkers in femto-Molar concentrations in real time. Last but not least, we propose a systematic policy to win the war against cancer that is a big challenge to science.


Assuntos
Nanoporos , Neoplasias , Biomarcadores Tumorais , Humanos , Mycobacterium smegmatis , Nanotecnologia , Neoplasias/diagnóstico , Porinas
4.
RSC Adv ; 11(46): 28996-29014, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35478559

RESUMO

Biological nanopores are revolutionizing human health by the great myriad of detection and diagnostic skills. Their nano-confined area and ingenious shape are suitable to investigate a diverse range of molecules that were difficult to identify with the previous techniques. Additionally, high throughput and label-free detection of target analytes instigated the exploration of new bacterial channel proteins such as Fragaceatoxin C (FraC), Cytolysin A (ClyA), Ferric hydroxamate uptake component A (FhuA) and Curli specific gene G (CsgG) along with the former ones, like α-hemolysin (αHL), Mycobacterium smegmatis porin A (MspA), aerolysin, bacteriophage phi 29 and Outer membrane porin G (OmpG). Herein, we discuss some well-known biological nanopores but emphasize on MspA and compare the effects of site-directed mutagenesis on the detection ability of its mutants in view of the surface charge distribution, voltage threshold and pore-analyte interaction. We also discuss illustrious and latest advances in biological nanopores for past 2-3 years due to limited space. Last but not the least, we elucidate our perspective for selecting a biological nanopore and propose some future directions to design a customized nanopore that would be suitable for DNA sequencing and sensing of other nontrivial molecules in question.

5.
Nat Prod Res ; 35(22): 4286-4294, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31872778

RESUMO

The methanolic extract of aerial parts of Tithonia tubaeformis showed significant antioxidant activity in DPPH assay. It was subjected to bioassay guided fractionation affording more active ethyl acetate fraction which on further purification led to the isolation and identification of a series of bioactive phenolic compounds having important biosynthetic relationship. Of these, 4-hydroxyphenethyl henicosanoate (tithonoid) is a new compound. Moreover, in the carrageenan induced paw edema test, significant attenuation of inflammation was also produced by the extract at 50-200 mg/kg. The structures of all the constituents were determined through spectroscopic methods. It is the first systematic biological and chemical investigation on T. tubaeformis, which showed that phenolics may play an important role in the antioxidant and anti-inflammatory activity of the plant, probably through synergism.


Assuntos
Antioxidantes , Tithonia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Carragenina , Edema/tratamento farmacológico , Fenóis/farmacologia , Fenóis/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Tirosina/uso terapêutico
6.
Pak J Pharm Sci ; 31(2): 385-392, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29618425

RESUMO

The study was aimed at evaluating various biological actions of widely consumed Areca catechu nut. The nut's ethanolic extract exhibited cytotoxicity (lung cancer cell line), embryotoxicity (chick embryo), phytotoxicity (Lemna minor), insecticidal (Rhyzopertha dominica), anti-bacterial (Pseudomonas aeruginosa), anti-fungal (Microsporum canis) and mitogenic (human blood lymphocytes) actions. The standardization results revealed presence of 1.7 µ g arecoline per mg of extract. In conclusion, the Areca nut is endowed with both harmful and beneficial biological actions. Keeping in view its wide consumption and ease of availability, the aforesaid information should be channelized for health and agricultural benefits.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Areca/química , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos Fitogênicos/química , Araceae/efeitos dos fármacos , Arecolina/análise , Artemia/efeitos dos fármacos , Linhagem Celular Tumoral , Embrião de Galinha/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Etanol/química , Humanos , Inseticidas/química , Índice Mitótico , Nozes/química , Extratos Vegetais/química , Extratos Vegetais/normas
7.
Bioorg Chem ; 78: 141-148, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29567428

RESUMO

Alzheimer is a neurodegenerative disease and requires the development of new scaffold to treat it. In this regard, thiazoles derivative are playing their significant role. In the current research paper we have focused our attention for the development of tetrasubstituted thiazole (3a-h) derivatives using domino synthesis by mixing the thiourea as a precursor, with acetophenone in the presence of iodine and tosic acid in DMSO and refluxed for 12-22 h. The structures of the newly synthesized compounds were confirmed by FTIR, 1H NMR, 13C NMR and EIMS analysis. Thiazole derivatives were analyzed for their biological significances against acetyl and butylcholinesterase enzymes and compound 3b and 3d were found more active against these enzyme, respectively. The mode of inhibition was determined for the potent compounds against both the enzymes. Moreover, the molecular docking studies were carried out to explore the interactive behavior of the compounds within the active pocket of enzymes. Furthermore, the derivatives (3a-h) were evaluated for their anticancer potential against HeLa cancer cell lines. Most potent inhibition was observed by compound 3b.


Assuntos
Acetilcolinesterase/metabolismo , Antineoplásicos/farmacologia , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Tiazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Electrophorus , Células HeLa , Cavalos , Humanos , Cinética , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
8.
Bioorg Chem ; 75: 62-70, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28917123

RESUMO

Recent efforts to develop cure for chronic diabetic complications have led to the discovery of potent inhibitors against aldose reductase (AKR1B1, EC 1.1.1.21) whose role in diabetes is well-evident. In the present work, two new natural products were isolated from the ariel part of Ocimum basilicum; 7-(3-hydroxypropyl)-3-methyl-8-ß-O-d-glucoside-2H-chromen-2-one (1) and E-4-(6'-hydroxyhex-3'-en-1-yl)phenyl propionate (2) and confirmed their structures with different spectroscopic techniques including NMR spectroscopy etc. The isolated compounds (1, 2) were evaluated for in vitro inhibitory activity against aldose reductase (AKR1B1) and aldehyde reductase (AKR1A1). The natural product (1) showed better inhibitory activity for AKR1B1 with IC50 value of 2.095±0.77µM compare to standard sorbinil (IC50=3.14±0.02µM). Moreover, the compound (1) also showed multifolds higher activity (IC50=0.783±0.07µM) against AKR1A1 as compared to standard valproic acid (IC50=57.4±0.89µM). However, the natural product (2) showed slightly lower activity for AKR1B1 (IC50=4.324±1.25µM). Moreover, the molecular docking studies of the potent inhibitors were also performed to identify the putative binding modes within the active site of aldose/aldehyde reductases.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Benzopiranos/química , Inibidores Enzimáticos/química , Glucosídeos/química , Ocimum basilicum/química , Fenilpropionatos/química , Aldeído Redutase/metabolismo , Benzopiranos/isolamento & purificação , Benzopiranos/metabolismo , Benzopiranos/farmacologia , Sítios de Ligação , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glucosídeos/isolamento & purificação , Glucosídeos/metabolismo , Glucosídeos/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , Ocimum basilicum/metabolismo , Fenilpropionatos/isolamento & purificação , Fenilpropionatos/metabolismo , Fenilpropionatos/farmacologia , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estrutura Terciária de Proteína
9.
Bioorg Chem ; 71: 10-18, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28139246

RESUMO

Owing to the biological importance of cyclic sulfonamides (sultams), herein we report a new, facile and cost-effective method for the synthesis of sultams that makes use of a reaction between dansyl amide and easily accessible benzaldehydes under mildly acidic conditions. All compounds were obtained in good yields (69-96%). Consequently a series of cyclic sulfonamides (7a-7n) was synthesized and characterized using FTIR, MS and NMR spectroscopy, crystal structure of compound 7b has also been determined. All compounds were evaluated for their potential to inhibit alkaline phosphatase (bTNAP and bIAP). All compounds were found to be excellent inhibitors of bTNAP with IC50 values in lower micro-molar range (0.11-6.63µM). Most of the compounds were selective inhibitors of bTNAP over bIAP. Only six compounds were found to be active against bIAP (IC50 values in the range 0.38-3.48µM). Molecular docking studies were carried out to identify and rationalize the structural elements necessary for efficient AP inhibition.


Assuntos
Fosfatase Alcalina/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Fosfatase Alcalina/química , Fosfatase Alcalina/metabolismo , Animais , Bovinos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
10.
Nat Prod Res ; 30(10): 1212-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26134381

RESUMO

The aim of the study was to explore the traditional use of Cinnamomum cassia against depression. The standardised methanolic extract of the bark of C. cassia was evaluated for antidepressant activity using various behavioural tests, i.e. tail suspension test (TST), forced swim test (FST) and locomotor activity test. The serotonergic and noradrenergic modulation was assessed using 5-hydroxytryptophan (5-HTP)-induced head twitches and yohimbine potentiation tests, respectively. The fluoxetine and phenelzine were used as positive controls in the study. The C. cassia extract significantly decreased the immobility time in TST (maximum effective dose tested was 50 mg/kg) while no effect was observed in FST and locomotor activity test. The extract significantly increased the 5-HTP-induced head twitches while yohimbine-induced lethality remained unaltered. The aforementioned results are similar to that caused by fluoxetine. The standardised methanolic extract of C. cassia demonstrated antidepressant activity that can be attributed to rise in serotonin levels.


Assuntos
Antidepressivos/farmacologia , Cinnamomum aromaticum/química , Depressão/tratamento farmacológico , Extratos Vegetais/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Antidepressivos/isolamento & purificação , Modelos Animais de Doenças , Fluoxetina/farmacologia , Elevação dos Membros Posteriores , Masculino , Camundongos Endogâmicos BALB C , Atividade Motora/efeitos dos fármacos , Casca de Planta/química , Ratos , Ratos Sprague-Dawley , Serotonina/análise , Inibidores Seletivos de Recaptação de Serotonina/isolamento & purificação , Natação , Ioimbina/farmacologia
11.
J Ethnopharmacol ; 144(1): 220-2, 2012 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-22982011

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ocimum basilicum belongs to the genus Ocimum (Lamiaceae). Many species of this genus including O. basilicum have been traditionally used for the treatment of a variety of diseases including respiratory diseases and symptoms of tuberculosis. AIM OF STUDY: The aim of the study was to evaluate the activity of pure constituents of O. basilicum, a plant used in traditional medicine to treat respiratory diseases including symptoms of tuberculosis, against Mycobacterium tuberculosis H37Rv. MATERIALS AND METHODS: The crude methanolic extract from the aerial parts (leaves, fruits and flowers) of the plant was separated into EtOAc and water subextracts and the EtOAc subextract was further divided into acidic and neutral fractions. Each of these was subjected to fractionation through column chromatography followed by prep. TLC. Several pure compounds were thus isolated and their activity was determined against M. tuberculosis H37Rv using MABA assay. RESULTS: Nine compounds were assayed for antituberculosis activity which exhibited upto 49% inhibition of M. tuberculosis H37Rv at 6.25 µg/mL. These include one new compound bacilicin, the structure of which was elucidated based on 2D-NMR (HSQC, HMBC, COSY and NOESY) and Ms spectral analysis. The known compounds were identified on the basis of comparison of their spectral data with those reported earlier. CONCLUSIONS: Inhibition of M. tuberculosis by pure compounds from O. basilicum supports the use of this plant in ethnomedicine as a remedy for symptoms of tuberculosis. The results also suggest that the activity of the plant may be due to a synergistic effect of active compounds including those investigated in the present studies, and hence this plant is a potential candidate for obtaining further new antituberculosis natural products.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Ocimum basilicum , Extratos Vegetais/farmacologia , Antituberculosos/química , Testes de Sensibilidade Microbiana , Componentes Aéreos da Planta , Extratos Vegetais/química
12.
Phytochemistry ; 77: 238-44, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22281382

RESUMO

A pentacyclic triterpene, oleanderocioic acid, two flavonoidal glycosides, quercetin-5-O-[α-L-rhamnopyranosyl-(1→6)]-ß-D-glucopyranoside and kaempferol-5-O-[α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranoside, and a cardenolide, oleandigoside, together with 11 known compounds, were isolated from the leaves of Nerium oleander. Their structures were elucidated on the basis of spectroscopic analysis. The growth inhibitory and cytotoxic activities of eight compounds were evaluated against the MCF-7 human breast cancer cell line using a sulforhodamine B assay. Three compounds, oleandrin, odoroside A and B were further assayed using a panel of 57 human cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Cardenolídeos/química , Flavonoides/química , Glicosídeos/química , Nerium/química , Triterpenos Pentacíclicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Cardenolídeos/isolamento & purificação , Cardenolídeos/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flavonoides/isolamento & purificação , Flavonoides/toxicidade , Glicosídeos/isolamento & purificação , Glicosídeos/toxicidade , Humanos , Células MCF-7 , Nerium/metabolismo , Ressonância Magnética Nuclear Biomolecular , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/toxicidade , Extratos Vegetais/química , Folhas de Planta/química
13.
Org Biomol Chem ; 8(1): 107-13, 2010 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20024140

RESUMO

Structural revision of lawsonicin, a natural product of Lawsonia alba, is reported based upon comparison of its spectral data with that of the naturally occurring dihydrobenzo[b]furan neolignan (rac)-trans-dihydrodehydrodiconiferyl alcohol, which is found to be identical. A concise synthesis of dihydrodehydrodiconiferyl alcohol, via Rh(2)[S-DOSP](4)-catalysed intramolecular C-H insertion, is described.


Assuntos
Lawsonia (Planta)/química , Lignina/análogos & derivados , Lignina/síntese química , Lignina/química , Estrutura Molecular
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