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1.
BMC Public Health ; 24(1): 676, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439011

RESUMO

BACKGROUND: Reproductive span is the foundation of every woman's health in later life. India is currently facing a growing burden of multiple morbidities among the women in their reproductive age group which may further increase over the coming decades. The purpose of the present study aimed to identify different modifiable and non-modifiable risk factors affecting multimorbidity among the women in reproductive age group in Indian context. METHODS: Secondary data were obtained from the Demography and Health Survey (DHS), conducted in India during 2019-2021. A total of 671,967 women aged 15-49 years were selected for this present study. Descriptive, association studies and multinominal logistic regression analyses were performed to accomplish the objectives. RESULTS: Currently, 6.3% of total study participant's reproductive age group women suffered from multimorbidity in India. Never consuming protein, fruits, vegetables and milk increase the chances of developing multimorbidity. Consumption of fried foods, aerated drinks and addiction towards tobacco and alcohol also has a greater influence on the prevalence of multimorbidity. The prevalence of multimorbidity is sharply increased with increasing age and Body Mass Index (BMI). Regionally, the prevalence of multimorbidity was found more among the women hailed from eastern and north-eastern India. CONCLUSION: To reduce the risk of developing multimorbidity, targeted interventions are needed in the form of educating every woman concerning the importance of having minimum health-related knowledge, maintaining healthy lifestyle, weight management and having proper and balanced diet.


Assuntos
Comportamento Aditivo , Multimorbidade , Adulto , Feminino , Humanos , Povo Asiático , Frutas , Índia/epidemiologia , Adolescente , Adulto Jovem , Pessoa de Meia-Idade
2.
ACS Appl Mater Interfaces ; 16(3): 3654-3664, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38211324

RESUMO

The development of high-performance electrostatic energy storage dielectrics is essential for various applications such as pulsed-power technologies, electric vehicles (EVs), electronic devices, and the high-temperature aviation sector. However, the usage of lead as a crucial component in conventional high-performance dielectric materials has raised severe environmental concerns. As a result of this, there is an urgent need to explore lead-free alternatives. Ferroelectric ceramics offer high energy density but lack stability at high temperatures. Here we present a lead-free (1 - x)BiFeO3-xCaTiO3 (x = 0.6, 0.7, and 0.8; BFO-CTO) ceramic capacitor with low dielectric loss, high thermal stability, and high energy density up to ∼200 °C. The introduction of CTO (x = 0.7) to the BFO matrix triggers a transition from the normal ferroelectrics to the relaxor ferroelectrics state, resulting in a high recoverable energy density of 1.18 J cm-3 at 190 °C with an ultrafast dielectric relaxation time of 44 µs. These results offer a promising, environmentally friendly, high-capacity ceramic capacitor material for high-frequency and high-temperature applications.

3.
RSC Adv ; 12(48): 30936-30951, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36349019

RESUMO

The co-evaporation approach was used to examine the host-guest interaction and to explore the cytotoxic and antibacterial properties of an important anti-cancer medication, 6-mercaptopurine monohydrate (6-MP) with ß-cyclodextrin (ß-CD). The UV-Vis investigation confirmed the inclusion complex's (IC) 1 : 1 stoichiometry and was also utilized to oversee the viability of this inclusion process. FTIR, NMR, and XRD, among other spectrometric techniques, revealed the mechanism of molecular interactions between ß-CD and 6-MP which was further hypothesized by DFT to verify tentative outcomes. TGA and DSC studies revealed that 6-MP's thermal stability increased after encapsulation. Because of the protection of drug 6-MP by ß-CD, the formed IC was found to have higher photostability. This work also predicts the release behavior of 6-MP in the presence of CT-DNA without any chemical changes. An evaluation of the complex's antibacterial activity in vitro revealed that it was more effective than pure 6-MP. The in vitro cytotoxic activity against the human kidney cancer cell line (ACHN) was also found to be significant for the IC (IC50 = 4.18 µM) compared to that of pure 6-MP (IC50 = 5.49 µM). These findings suggest that 6-MP incorporation via ß-CD may result in 6-MP stability and effective presentation of its solubility, cytotoxic and antibacterial properties.

4.
Chemistry ; 28(5): e202103406, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34825743

RESUMO

Metallo-supramolecular self-assembly has yielded a plethora of discrete nanosystems, many of which show competence in capturing guests and catalyzing chemical reactions. However, the potential of low-molecular bottom-up self-assemblies in the development of structured inorganic materials has rarely been methodically explored so far. Herein, we present a new type of metallo-supramolecular surfactant with the ability to stabilize non-aqueous emulsions for a significant period. The molecular design of the surfactant is based on a heteroleptic coordination cage (CGA-3; CGA=Cage-based Gemini Amphiphile), assembled from two pairs of organic building blocks, grouped around two Pd(II) cations. Shape-complementarity between the differently functionalized components generates discrete amphiphiles with a tailor-made polarity profile, able to stabilize non-aqueous emulsions, such as hexadecane-in-DMSO. These emulsions were used as a medium for the synthesis of spherical metal oxide microcapsules (titanium oxide, zirconium oxide, and niobium oxide) from soluble, water-sensitive alkoxide precursors by allowing a controlled dosage of water to the liquid-liquid phase boundary. Synthesized materials were analyzed by a combination of electron microscopic techniques. In situ liquid cell transmission electron microscopy (LC-TEM) was utilized for the first time to visualize the dynamics of the emulsion-templated formation of hollow inorganic titanium oxide and zirconium oxide microspheres.


Assuntos
Óxidos , Tensoativos , Cápsulas , Emulsões , Microscopia Eletrônica de Transmissão
5.
J Mol Struct ; 1247: 131371, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34462609

RESUMO

Novel-Coronavirus (COVID-19) outburst has become a worldwide pandemic which threaten the scientific community to design and discover efficient and effective treatment strategies against this deadly virus (SARS-CoV-2). Still now, there is no antiviral therapy or drug available in the market which can efficiently combat the infection caused by this virus. In this respect, using available drugs by screening with molecular docking and molecular dynamics studies not only minimizes lengthy chemical trials but also reduces discovery cost for the pharmaceutical industry. During the COVID-19 pandemic situations hydroxychloroquine, chloroquine known as HCQ and CQ tablets have gained popularity as for the treatment coronavirus (COVID-19) but the main threatening effect of HCQ, CQ use lies on their side effects like blistering, peeling, loosening of the skin, blurred vision stomach pain, diarrhea, chest discomfort, pain, or tightness, cough or hoarseness which require immediate medical attention. Encapsulation of HCQ and CQ drugs by the cyclic macromolecules such as α and ß-Cyclodextrin, to form host-guest complexes is very effective strategy to mask the cytotoxicity of certain drugs and alleviating and modulating side effects of drug applications. In the present work, we have encapsulated the HCQ and CQ drugs α and ß-Cyclodextrin and made a comprehensive analysis of stability, optical properties. Details analysis verified that between QC and HCQ, HQC showed stronger affinity towards ß-Cyclodextrin. This strategy can reduce the side effect of HCQ and CQ thereby offers a new way to use these drugs. We hope the present study should help the researchers to develop potential therapeutics against the novel coronavirus.

6.
J Am Chem Soc ; 140(50): 17384-17388, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30516378

RESUMO

Self-assembled, porous coordination cages with a functional interior find application in controlled guest inclusion/release, drug delivery, separation processes, and catalysis. However, only few studies exist that describe their utilization for the development of self-assembled materials based on their 3-dimensional shape and external functionalization. Here, dodecyl chain-containing, acridone-based ligands (LA) and shape-complementary phenanthrene-derived ligands (LB) are shown to self-assemble to heteroleptic coordination cages cis-[Pd2(LA)2(LB)2]4+ acting as a gemini amphiphile (CGA-1; Cage-based Gemini Amphiphile-1). Owing to their anisotropic decoration with short polar and long nonpolar side chains, the cationic cages were found to assemble into vesicles with diameters larger than 100 nm in suitable polar solvents, visualized by cryo-TEM and Liquid-Cell Transmission Electron Microscopy (LC-TEM). LC-TEM reveals that these vesicles aggregate into chains and necklaces via long-range interactions. In addition, the cages show a rarely described ability to stabilize oil-in-oil emulsions.

7.
Sci Rep ; 8(1): 13031, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158645

RESUMO

Host-guest interaction of two significant drugs, phenylephrine hydrochloride and synephrine with α and ß-cyclodextrins were studied systematically. Initially two simple but reliable physicochemical techniques namely conductance and surface tension were employed to find out saturation concentration for the inclusion and its stoichiometry. The obtained 1:1 stoichiometry was further confirmed by two spectrometric methods, UV-Vis study and spectrofluorimetry. Significant shifts in IR stretching frequency also support the inclusion process. Relative stabilities of the inclusion complexes were established by the association constants obtained from UV-Vis spectroscopic measurements, program based mathematical calculation of conductivity data. Calculations of the thermodynamic parameters dictates thermodynamic feasibility of the inclusion process. Spectrofluorometric measurement scaffolds the UV-Vis spectroscopic measurement validating stability of the ICs once again. Mass spectroscopic measurement gives the molecular ion peaks corresponding to the inclusion complex of 1:1 molar ratio of host and guest molecules. The mechanism of inclusion was drawn by 1H-NMR and 2D ROESY spectroscopic analysis. Surface texture of the inclusion complexes was studied by SEM. Finally, the cytotoxic activities of the inclusion complexes were analyzed and found, Cell viability also balances for non-toxic behavior of the ICs. Moreover, all the studies reveal the formation of inclusion complexes of two ephedra free, alternatively emerging drugs (after their banned product having ephedra) SNP, PEH with α and ß-CD which enriches the drug delivery system with their regulatory release without any chemical modification.


Assuntos
Fármacos Antiobesidade/farmacologia , Ciclodextrinas/farmacologia , Fenilefrina/farmacologia , Sinefrina/farmacologia , alfa-Ciclodextrinas/farmacologia , beta-Ciclodextrinas/farmacologia , Fármacos Antiobesidade/síntese química , Fármacos Antiobesidade/química , Fármacos Antiobesidade/toxicidade , Ciclodextrinas/síntese química , Ciclodextrinas/química , Ciclodextrinas/toxicidade , Estabilidade de Medicamentos , Viabilidade Microbiana/efeitos dos fármacos , Fenilefrina/síntese química , Fenilefrina/química , Fenilefrina/toxicidade , Análise Espectral , Sinefrina/síntese química , Sinefrina/química , Sinefrina/toxicidade , alfa-Ciclodextrinas/síntese química , alfa-Ciclodextrinas/química , alfa-Ciclodextrinas/toxicidade , beta-Ciclodextrinas/síntese química , beta-Ciclodextrinas/química , beta-Ciclodextrinas/toxicidade
8.
Chem Sci ; 8(10): 6799-6803, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29147503

RESUMO

We report a new strategy for the synthesis of robust hierarchical micro- and mesoporous MOFs from water stable MOFs via a selective acid etching process. The process is controlled by the size-selective diffusion of acid molecules through the MOF windows. This method enables the fine-tuning of the porosity of hierarchical MOFs, allowing for the generation of well-defined mesopores with high mesopore volume. Because of the size-selective diffusion of acid molecules, the inherent crystallinity and external morphology of the resulting MOFs are well-maintained after acid treatment. This novel strategy may provide an alternative route towards the synthesis of diverse hierarchical MOFs.

9.
Sci Rep ; 6: 35764, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27762346

RESUMO

Host-guest inclusion complexes of ß-cyclodextrin with two vitamins viz., nicotinic acid and ascorbic acid in aqueous medium have been explored by reliable spectroscopic, physicochemical and calorimetric methods as stabilizer, carrier and regulatory releaser of the guest molecules. Job's plots have been drawn by UV-visible spectroscopy to confirm the 1:1 stoichiometry of the host-guest assembly. Stereo-chemical nature of the inclusion complexes has been explained by 2D NMR spectroscopy. Surface tension and conductivity studies further support the inclusion process. Association constants for the vitamin-ß-CD inclusion complexes have been calculated by UV-visible spectroscopy using both Benesi-Hildebrand method and non-linear programme, while the thermodynamic parameters have been estimated with the help of van't Hoff equation. Isothermal titration calorimetric studies have been performed to determine the stoichiometry, association constant and thermodynamic parameters with high accuracy. The outcomes reveal that there is a drop in ΔSo, which is overcome by higher negative value of ΔHo, making the overall inclusion process thermodynamically favorable. The association constant is found to be higher for ascorbic acid than that for nicotinic acid, which has been explained on the basis of their molecular structures.


Assuntos
Ácido Ascórbico/química , Fenômenos Químicos , Niacina/química , Vitaminas/química , beta-Ciclodextrinas/química , Calorimetria , Aditivos Alimentares/química , Sequestrantes/química , Análise Espectral
10.
Carbohydr Polym ; 151: 458-466, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474589

RESUMO

Formations of host-guest inclusion complexes of two natural amino acids, viz., l-Leucine and l-Isoleucine as guests with α and ß-cyclodextrins have been investigated which include diverse applications in modern science such as controlled delivery in the field of pharmaceuticals, food processing etc. Surface tension and conductivity studies establish the formation of inclusion complexes with 1:1 stoichiometry. The interactions of cyclodextrins with amino acids have been supported by density, viscosity, refractive index, hydration and solvation number measurements indicating higher degree of inclusion in case of α-cyclodextrin. l-Leucine interacts more with the hydrophobic cavity of cyclodextrin than its isomer. With the help of stability constant by NMR titration, hydrophobic effect, H-bonds and structural effects the formations of inclusion complexes have been explained.


Assuntos
Isoleucina/química , Leucina/química , alfa-Ciclodextrinas/química , beta-Ciclodextrinas/química , Concentração de Íons de Hidrogênio , Espectroscopia de Prótons por Ressonância Magnética , Propriedades de Superfície , Viscosidade
11.
Chem Sci ; 6(1): 603-607, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28706627

RESUMO

A proton conducting metallogel [FNPA; ferric nitrate (FN)-phytic acid (PA)] is synthesized by immobilizing a protogenic ligand (phytic acid) using iron(iii) nitrate in DMF. The xerogel shows high proton conductivity of 2.4 × 10-2 S cm-1 at 120 °C, the best value known among all metal organic materials (MOMs). Marking the first such attempt in MOMs, an electrode made using the xerogel showed a power density of 0.94 mW cm-2 at 0.6 V under dry fuel cell conditions.

12.
J Am Chem Soc ; 136(42): 14845-51, 2014 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-25279940

RESUMO

Cadmium sulfide (CdS) quantum dots (<10 nm in size) have been successfully synthesized in situ without any capping agent in a Zn(II)-based low-molecular-weight metallohydrogel (ZAVA). Pristine ZAVA hydrogel shows blue luminescence, but the emission can be tuned upon encapsulation of the CdS quantum dots. Time-dependent tunable emission (white to yellow to orange) of the CdS incubated gel (CdS@ZAVA gel) can be attributed to sluggish growth of the quantum dots inside the gel matrix. Once CdS quantum dots are entrapped, their augmentation can be stopped by converting the gel into xerogel, wherein the quantum dots remains embedded in the solid xerogel matrix. Similar size stabilization of CdS quantum dots can be achieved by means of a unique room-temperature conversion of the CdS incubated ZAVA gel to CdS incubated MOF (CdS@ZAVCl) crystals. This in turn arrests the tunability in emission owing to the restriction in the growth of CdS quantum dots inside xerogel and MOF. These CdS embedded MOFs have been utilized as a catalyst for water splitting under visible light.

13.
Chem Commun (Camb) ; 50(53): 7032-5, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24849945

RESUMO

Two metallohydrogels based on an amino acid-based ligand and Zn(II) salts were synthesized. These hydrogels show an uncommon, reversible, time-dependent transformation from the opaque to transparent state. These hydrogels also exhibit gradual dissolution in water (pH ≤ 7) over time. A water-soluble stimulant, caffeine, could be in situ loaded into the hydrogels and slowly released during dissolution.


Assuntos
Hidrogéis/química , Metais/química , Aminoácidos/química , Cafeína/administração & dosagem , Cafeína/química , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/química , Preparações de Ação Retardada , Estabilidade de Medicamentos , Cinética , Ligantes , Solubilidade , Zinco/química
14.
Chem Commun (Camb) ; 50(23): 3004-6, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24515099

RESUMO

A multiresponsive metallohydrogel based on an amino acid-derived low molecular weight (LMW) ligand and a Zn(II) salt was prepared. This hydrogel showed remarkable shape-persistent, self-standing, load-bearing and self-healing properties, which is uncommon in LMW hydrogels.


Assuntos
Aminoácidos/química , Complexos de Coordenação/química , Hidrogéis/química , Zinco/química , Transição de Fase , Sais/química , Suporte de Carga
15.
Chemistry ; 19(29): 9562-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23749647

RESUMO

Oxalic acid has been proven to be the lowest molecular weight organic ligand able to form robust supramolecular metallogel networks in the presence of metal salts. In particular, two novel multifunctional metallogels were readily prepared at room temperature by simple mixing of stock solutions of Cu(II) acetate monohydrate or Cu(II) perchlorate hexahydrate and oxalic acid dihydrate. Formation of different polymorphs and unprecedented proton conduction under anhydrous conditions were also demonstrated with some of these materials.

16.
Chem Commun (Camb) ; 49(46): 5262-4, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23636534

RESUMO

Eight Zn-based porous (1.2 nm) homochiral MOFs (ValZnX, AlaZnX, X = Cl(-), Br(-), HCO2(-) and CH3CO2(-)) were synthesized which possess extremely rare zeolitic (unh) topology. These MOFs show an unprecedented hydrolytic regenerability. Salt metathesis reaction performed on these 3D MOFs in water resulted in 2D coordination polymers (CPs).

17.
Org Biomol Chem ; 11(18): 3057-63, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23536201

RESUMO

We have designed and synthesized a novel fluorescent molecular probe using the Cu(i)-catalyzed Huisgen cycloaddition of 1,3-diethynyl-6-fluoroisoquinoline with 1-(2-azidoethyl)pyrrolidine. This water soluble "click" fluorescent chemosensor displays good sensitivity towards heavy and transition metal ions. It shows pronounced fluorescence enhancement and high selectivity for Zn(2+) over other biologically relevant metal ions in water at pH 7.0. The fluorescence response of the bis-triazole derivative in the presence of Zn(2+) is switchable and reversible as a function of pH. The chemosensor also exhibits fluorescence quenching with Fe(2+) and Cu(2+) in water at pH 7.0. A modified YES logic gate property has been proposed using the "turn-on" and "turn-off" behavior of the bis-triazole with Zn(2+) and Fe(2+). The sensor is cell membrane permeable and applicable for intracellular Zn(2+) imaging.


Assuntos
Corantes Fluorescentes/síntese química , Metais Pesados/química , Elementos de Transição/análise , Linhagem Celular Tumoral , Cobre/química , Corantes Fluorescentes/química , Humanos , Concentração de Íons de Hidrogênio , Ferro/análise , Microscopia Confocal , Água/química , Zinco/análise
18.
Inorg Chem ; 50(4): 1392-401, 2011 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-21192733

RESUMO

A new three-dimensional magnesium formate polymorph, namely, γ-[Mg(3)(O(2)CH)(6)] has been synthesized via in situ formate anion generation method. γ-Mg-formate crystallizes in space group Pbcn, and structural determination by X-ray single crystal diffraction reveals a three-dimensional network of Mg(2+) linked by formate anions. All formate anions possess similar binding mode to the metal center with one oxygen of a particular formate anion binds to one metal center (µ(1) oxygen) and other oxygen binds to two metal centers (µ(2) oxygen). N(2) adsorption studies indicate that the framework displays permanent porosity. The specific surface area of γ-Mg-formate (BET, 120 m(2) gm(-1)) is lower than the α- polymorph (BET, 150 m(2) gm(-1)). However, the initial hydrogen uptake of γ-Mg-formate reached almost 1.0 wt % when the adsorbate pressure approached 760 Torr at 77 K. This is higher than the hydrogen uptake of α-Mg-formate (0.6 wt %). γ-Mg-formate, shows a moderate affinity and capacity for CO(2) (3.4 Å kinetic diameter) at 298 K. The CO(2) uptake at 760 Torr is 2.01 mmol gm(-1) (47.0 cc gm(-1)). Although this CO(2) uptake is somewhat modest, it compares well with the CO(2) uptake of several Mg-MOFs and ZIFs reported in the literature.


Assuntos
Formiatos/química , Gases/química , Magnésio/química , Compostos Organometálicos/química , Adsorção , Dióxido de Carbono/química , Cátions Bivalentes , Cristalografia por Raios X , Nitrogênio/química , Compostos Organometálicos/síntese química , Oxigênio/química , Porosidade , Temperatura
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