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1.
Adv Mater ; 36(18): e2310938, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38245860

RESUMO

The development of metal-free bifunctional electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER) is significant but rarely demonstrated. Porous organic polymers (POPs) with well-defined electroactive functionalities show superior performance in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Precise control of the active sites' local environment requires careful modulation of linkers through the judicious selection of building units. Here, a systematic strategy is introduced for modulating functionality to design and synthesize a series of thianthrene-based bifunctional sp2 C═C bonded POPs with hollow spherical morphologies exhibiting superior electrocatalytic activity. This precise structural tuning allowed to gain insight into the effects of heteroatom incorporation, hydrophilicity, and variations in linker length on electrocatalytic activity. The most efficient bifunctional electrocatalyst THT-PyDAN achieves a current density of 10 mA cm─2 at an overpotential (η10) of ≈65 mV (in 0.5 m H2SO4) and ≈283 mV (in 1 m KOH) for HER and OER, respectively. THT-PyDAN exhibits superior activity to all previously reported metal-free bifunctional electrocatalysts in the literature. Furthermore, these investigations demonstrate that THT-PyDAN maintains its performance even after 36 h of chronoamperometry and 1000 CV cycling. Post-catalytic characterization using FT-IR, XPS, and microscopic imaging techniques underscores the long-term durability of THT-PyDAN.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36734898

RESUMO

Dilated cardiomyopathy (DCM) is distinguished by ventricular chamber expansion, systolic dysfunction, and normal left ventricular (LV) wall thickness, and is mainly caused due to genetic or environmental factors; however, its aetiology is undetermined in the majority of patients. The focus of this work is on pathogenesis, small animal models, as well as the herbal medicinal approach, and the most recent advances in imaging modalities for patients with dilated cardiomyopathy. Several small animal models have been proposed over the last few years to mimic various pathomechanisms that contribute to dilated cardiomyopathy. Surgical procedures, gene mutations, and drug therapies are all characteristic features of these models. The pros and cons, including heart failure stimulation of extensively established small animal models for dilated cardiomyopathy, are illustrated, as these models tend to procure key insights and contribute to the development of innovative treatment techniques for patients. Traditional medicinal plants used as treatment in these models are also discussed, along with contemporary developments in herbal therapies. In the last few decades, accurate diagnosis, proper recognition of the underlying disease, specific risk stratification, and forecasting of clinical outcome, have indeed improved the health of DCM patients. Cardiac magnetic resonance (CMR) is the bullion criterion for assessing ventricular volume and ejection fraction in a reliable and consistent direction. Other technologies, like strain analysis and 3D echocardiography, have enhanced this technique's predictive and therapeutic potential. Nuclear imaging potentially helps doctors pinpoint the causative factors of left ventricular dysfunction, as with cardiac sarcoidosis and amyloidosis.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/etiologia , Volume Sistólico , Coração , Insuficiência Cardíaca/complicações , Imagem Multimodal/efeitos adversos
3.
Acta Pharm ; 73(1): 29-42, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36692461

RESUMO

This century's most serious catastrophe, COVID-19, has been dubbed "the most life-threatening disaster ever". Asthmatic persons are even more prone to COVID-19's complex interplay with the underlying inflammatory condition. In order to protect themselves against COVID-19, asthmatic patients must be very vigilant in their usage of therapeutic techniques and drugs (e.g., bronchodilators, 5-lipoxygenase inhibitors), which may be accessed to deal with mild, moderate, and severe COVID-19 indications. People with asthma may have more severe COVID-19 symptoms, which may lead to a worsening of their condition. Several cytokines were found to be elevated in the bronchial tracts of patients with acute instances of COVID-19, suggesting that this ailment may aggravate asthma episodes by increasing inflammation. The intensity of COVID-19 symptoms is lessened in patients with asthma who have superior levels of T-cells. Several antibiotics, antivirals, antipyretics, and anti-inflammatory drugs have been suggested to suppress COVID-19 symptoms in asthmatic persons. Furthermore, smokers are more likely to have aggravated repercussions in COVID-19 infection. Being hospitalized to critical care due to COVID-19, needing mechanical breathing, and suffering from serious health repercussions, are all possible outcomes for someone who has previously smoked. Smoking damages airways and alveoli, which significantly raises the risk of COVID-19-related health complications. Patients with a previous record of smoking are predisposed to severe COVID-19 disease symptoms that essentially require a combination of bronchodilators, mucolytics, antivirals, and antimuscarinic drugs, to cope with the situation. The present review discusses the care and management of asthmatic and smoker patients in COVID-19 infection.


Assuntos
Asma , COVID-19 , Humanos , COVID-19/complicações , Fumantes , Broncodilatadores/uso terapêutico , Asma/tratamento farmacológico , Asma/epidemiologia , Asma/diagnóstico , Cuidados Críticos
5.
Artigo em Inglês | MEDLINE | ID: mdl-36051494

RESUMO

Cassia fistula Linn, generally recognized as Indian laburnum, is one of the ancient trees in the Indian subcontinent used for its ornamental and diverse medicinal properties. It is known for its ethnic medicinal uses in inflammatory and infectious pathologies such as antihelmintic, purgative, carminative, antipyretic, expectorant, analgesic, laxative, antiseptic, and antidote against snake poison. The Cassia bark is rich in anthraquinones, flavanols glycosides, and sitosterols, which renders it cardioprotective properties. The existing experiments were designed to assess the potential of Cassia fistula bark against isoproterenol (ISP)-induced cardiotoxicity in rats, which has not been validated yet. The bark was successively extracted with five different solvents, and each extract was subjected to in vitro antioxidant studies. Further acute oral toxicity assays were carried out preceding in vivo myocardial studies. Cardiotoxicity-inducing agent, ISP, was administrated to the rats for two consecutive days (8th and 9th). Based on in vitro studies, the Cassia fistula methanolic extract (CFME) was administered in two doses: CFME-LD (lower dose 250 mg/kg) and CFME-HD (high dose 500 mg/kg) separately. It was found that CFME produced a substantial decrease in lipid peroxidation and an increase in antioxidants in myocardial tissues. CFME abrogated the levels of triglyceride and total cholesterol with a decrease in alanine transaminase (ALT) and aspartate transaminase (AST) activity in serum at both doses. 2,3,5-Triphenyltetrazolium chloride (TTC) staining and histopathology also revealed the protective effects of CFME against ISP-induced myocardial infarction. The study showed the significant role of the CFME as a strong antioxidant and cardioprotective action in ISP-induced toxicity.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36034950

RESUMO

Phytochemicals have been shown to possess multiple bioactives and have been reported to showcase many medicinal effects. A similar kind of evaluation of phytoconstituents for their antimicrobial action has been reported, based on in vitro and in silico data. The goal of the research was to explore bioactive phytoconstituents of Eclipta alba leaf for antimicrobial activity. The antimicrobial activity was validated by both molecular docking and antimicrobial assay. Bioactive metabolites were identified using GC-MS. The antimicrobial and antimycobacterial activity of Eclipta alba leaves was investigated using the Kirby-Bauer well diffusion method and the rapid culture-MGIT™ DST method against a variety of human pathogens, as well as Mycobacterium tuberculosis (H37Rv) and Mycobacterium tuberculosis bacteria resistant to isoniazid and rifampicin. Eclipta alba's GC-MS studies confirmed the detection of 17 bioactive constituents. The extract demonstrates the highest antibacterial activity against Escherichia coli (sensitive), Pseudomonas aeruginosa (sensitive) and methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa susceptible and MRSA (sensitive) with zone of inhibition of 27 mm, 24 mm, and 32 mm respectively. The extract showed no effect on Mycobacterium tuberculosis (H37Rv) and Mycobacterium tuberculosis bacteria resistant to isoniazid and rifampicin in antimycobacterial activity testing. Molecular docking investigation revealed that three compounds (phthalic acid, isobutyl octadecyl ester, hexadecanoic acid, 1(hydroxymethyl)1,2-ethanediylester, and 2,myristynoyl pantetheine) have generated the best results in terms of binding energies and significant interactions with key residues of target protein 3-hydroxydecanoyl-acyl carrier protein dehydratase (FabA) and confirm its activity as antimicrobial inhibitors. These two-dimensional plots show significant protein-ligand binding interactions (van der Waals interactions, hydrogen bond, alkyl, and Pi-alkyl interactions). ADMET (absorption, distribution, metabolism, excretion, and toxicity) results additionally support the drug-likeness characteristics of concluded potential compounds. The experimental and computational results demonstrated that methanolic extract of Eclipta alba leaves had antimicrobial effects for specific infections due to the presence of phytochemical compounds.

8.
ACS Omega ; 7(20): 16906-16916, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35647428

RESUMO

Graphene oxide-based nanocomposites (NCMs) exhibit diverse photonic and biophotonic applications. Innovative nanoengineering using a task-specific ionic liquid (IL), namely, 1-butyl-3-methyl tetrafluoroborate [C4mim][BF4], allows one to access a unique class of luminescent nanocomposites formed between lanthanide-doped binary fluorides and graphene oxide (GO). Here the IL is used as a solvent, templating agent, and as a reaction partner for the nanocomposite synthesis, that is, "all three in one". Our study shows that GO controls the size of the NCMs; however, it can tune the luminescence properties too. For example, the excitation spectrum of Ce3+ is higher-energy shifted when GO is attached. In addition, magnetic properties of GdF3:Tb3+ nanoparticles (NPs) and GdF3:Tb3+-GO NCMs are also studied at room temperature (300 K) and very low temperature (2 K). High magnetization results for the NPs (e.g., 6.676 emu g-1 at 300 K and 184.449 emu g-1 at 2 K in the applied magnetic field from +50 to -50 kOe) and NCMs promises their uses in many photonic and biphotonic applications including magnetic resonance imaging, etc.

9.
Front Chem ; 9: 715531, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513795

RESUMO

Lanthanide (Ln3+) ion(s)-doped or rare-earth ion(s)-doped nanomaterials have been considered a very important class of nanophosphors for various photonic and biophotonic applications. Unlike semiconductors and organic-based luminescent particles, the optical properties of Ln3+-doped nanophosphors are independent of the size of the nanoparticles. However, by varying the crystal phase, morphology, and lattice strain of the host materials along with making core-shell structure, the relaxation dynamics of dopant Ln3+ ions can be effectively tuned. Interestingly, a judicious choice of dopant ions leads to unparallel photophysical dynamics, such as quantum cutting, upconversion, and energy transfer. Recently, ionic liquids (ILs) have drawn tremendous attention in the field of nanomaterials synthesis due to their unique properties like negligible vapor pressure, nonflammability, and, most importantly, tunability; thus, they are often called "green" and "designer" solvents. This review article provides a critical overview of the latest developments in the ILs-assisted synthesis of rare-earth-doped nanomaterials and their subsequent photonic/biophotonic applications, such as energy-efficient lighting and solar cell applications, photodynamic therapy, and in vivo and in vitro bioimaging. This article will emphasize how luminescence dynamics of dopant rare-earth ions can be tuned by changing the basic properties of the host materials like crystal phase, morphology, and lattice strain, which can be eventually tuned by various properties of ILs such as cation/anion combination, alkyl chain length, and viscosity. Last but not least, different aspects of ILs like their ability to act as templating agents, solvents, and reaction partners and sometimes their "three-in-one" use in nanomaterials synthesis are highlighted along with various photoluminescence mechanisms of Ln3+ ion like up- and downconversion (UC and DC).

10.
Biomater Sci ; 8(23): 6730-6740, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33111724

RESUMO

Nanoparticles with biomedical applications should be evaluated for their biocompatibility. Rare-earth doped nanoparticles with unique spectral properties are superior in vivo optical probes in comparison with quantum dots and organic dyes, however, studies describing their nano-bio interactions are still limited. Here, we have evaluated the nano-bio interactions of green-synthesized, phase-pure BaF2 nanoparticles doped with rare-earth (RE3+ = Ce3+/Tb3+) ions using larval zebrafish. We found that zebrafish can tolerate a wide concentration range of these nanoparticles, as the maximal lethality was observed at very high concentrations (more than 200 mg L-1) upon five days of continuous exposure. At a concentration of 10 mg L-1, at which Zn2+, Ti4+ and Ag+ nanoparticles are reported to be lethal to developing zebrafish, continuous exposure to our nanoparticles for four days produced no developmental anomalies, craniofacial defects, cardiac toxicity or behavioural abnormalities in the developing zebrafish larvae. We have also found that the doping of rare-earth ions has no major effect on these biomarkers. Interestingly, the function of acetylcholinesterase (AChE) and the cellular metabolic activity of whole zebrafish larvae remained unchanged, even during continuous exposure to these nanoparticles at 150 mg L-1 for four days; however, severe developmental toxicities were evident at this high concentration. Based on these results, we can conclude that the biocompatibility of rare-earth doped nanoparticles is concentration dependent. Not all biomarkers are sensitive to these nanoparticles. The high concentration-dependent toxicity occurs through a mechanism distinct from changes in the metabolic or AChE activity. The significance of these findings lies in using these nanoparticles for bioimaging applications and biomarker studies, especially for prolonged exposure times.


Assuntos
Metais Terras Raras , Nanopartículas , Animais , Larva , Metais Terras Raras/toxicidade , Nanopartículas/toxicidade , Titânio , Peixe-Zebra
13.
Front Chem ; 6: 548, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519555

RESUMO

Water hyacinth (WH) is a troublesome aquatic weed of natural and artificial water bodies of India and other tropical countries and causing severe ecological problems. The WH biomass is low in lignin content and contains high amount of cellulose and hemicellulose, making it suitable material for conversion into liquid fuels for energy production. This study highlighted that, how different imidazolium based ionic liquids (ILs) [1-alkyl-3-methylimidazolium bromide, [Cnmim]Br (n = 2, 4, 6, 8, and 10)] with tunable properties can be employed for the degradation of WH biomass. Different characterizations techniques, such as XRD, FT-IR, SEM, and DSC are used to unravel the interplay between ILs and the biomass. In this study, it is observed that [Emim][Br] pretreated samples have maximum crystalline value (Crl = 26.38%) as compared to other ionic liquids pretreatments. FTIR data showed the removal of lignin from WH biomass by 12.77% for [Emim][Br] and 10.74% for [Edmim][Br]. SEM images have proven that [Emim][Br] pretreatment have altered the structure of biomass the most. Our results proved that IL pretreatment is a promising approach for effective treatment of WH biomass and causes high levels disruption of cellulose structure.

14.
Lung India ; 35(1): 70-72, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29319040

RESUMO

Pulmonary mucormycosis is a life-threatening opportunistic fungal infection. It is considered as a disease of immunocompromised state and is rarely seen in immunocompetent patients. We here report a case of refractory bronchovascular pleuropulmonary mucormycosis, who despite early detection, optimal management with liposomal amphotericin B, and posaconazole therapy followed by surgery, progressed further and led to a fatal outcome. Dual antifungal therapy combined with surgery is the only definitive treatment option available in the literature. Many new therapeutic options for mucormycosis treatment have become available but none have shown promising results, and larger studies are required to assess their efficacy.

15.
Sarcoidosis Vasc Diffuse Lung Dis ; 35(3): 285-288, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32476914

RESUMO

Sarcoidosis is an inflammatory multisystem disease which rarely may coexist in patients with other autoimmune disease like ankylosing spondylitis (AS). The presence of such as association causes diagnostic and management dilemmas as sarcoidosis has been reported to develop in patients of AS treated with tumour necrosis factor alpha (TNF-α) inhibitors. We describe a 49-year-old male with ankylosing spondylitis and histologically proven sarcoidosis who was treated with infliximab and improved. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 285-288).

16.
Indian J Med Res ; 145(5): 629-634, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28948953

RESUMO

BACKGROUND & OBJECTIVES: Glanzmann thrombasthenia (GT) is a rare, inherited autosomal recessive disorder characterized by qualitative or quantitative deficiency of integrin αIIbß3 [glycoprotein IIb (GPIIb)/IIIa, CD41/CD61] diagnosed by absent or reduced platelet aggregation to physiological agonists, namely, collagen, adenosine-di-phosphate, epinephrine and arachidonic acid. The objective of this study was to quantitate platelet surface GPs, classify GT patients and relate the results with the severity of bleeding and platelet aggregation studies. METHODS: Fifty one patients of GT diagnosed by platelet aggregation studies were evaluated for the expression of CD41, CD61, CD42a and CD42b on platelet surface by flow cytometry. The association between the clinical phenotype based on bleeding score and GT subtype on flow cytometric evaluation was assessed. RESULTS: Twenty four (47%) patients of GT were classified as type I (as CD41/CD61 were virtually absent, <5%), six (11.8%) patients as type II (5-20% CD41/CD61) and 21 (41.2%) as type III or GT variants as they had near normal levels of CD41 and CD61. Type III GT patients had significantly lower numbers of severe bleeders (P=0.034), but the severity of bleeding did not vary significantly in type I and II GT patients. In all GT patients, mean CD41 expression was found to be lower than mean CD61 expression (P=0.002). INTERPRETATION & CONCLUSIONS: Type I GT was found most common in our patients and with lowered mean CD41 expression in comparison with CD61. Type III GT patients had significantly lower numbers of severe bleeders, but the severity of bleeding did not vary significantly in type I and II GT patients.


Assuntos
Hemorragia/sangue , Integrina beta3/genética , Glicoproteína IIb da Membrana de Plaquetas/genética , Trombastenia/genética , Adulto , Plaquetas/metabolismo , Plaquetas/patologia , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Glicoproteínas/sangue , Hemorragia/genética , Hemorragia/patologia , Humanos , Integrina beta3/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Agregação Plaquetária/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Glicoproteína IIb da Membrana de Plaquetas/sangue , Trombastenia/sangue , Trombastenia/patologia
17.
Lung India ; 34(4): 368-371, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28671169

RESUMO

Hemoptysis is considered as a medical emergency which requires urgent stabilization with identification and correction of underlying etiology. Diagnosis of the cause of hemoptysis is not always readily identified after bronchoscopy and conventional computed tomography (CT) chest. Arteriovenous malformation (AVM) is a rare but important cause of massive hemoptysis which can be easily picked up by the use of double turn contrast CT chest. We here report a rare congenital AVM anomaly called Klippel-Trenaunay-Parks-Weber syndrome as a cause of massive hemoptysis and utility of double turn CT in diagnosing AVM as a cause of hemoptysis.

18.
Lung India ; 34(2): 179-181, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28360470

RESUMO

Pulmonary mucormycosis is an opportunistic fungal infection in immunocompromised individuals. It is difficult to diagnose as it requires tissue biopsy, and generally these patients are unfit to undergo invasive lung biopsies. We describe a novel technique in a case with uncontrolled diabetes mellitus with nonresolving pulmonary cavitary disease where convex probe endobronchial ultrasound (EBUS)-guided aspiration of lung cavity wall showed classical histopathological picture establishing the diagnosis of mucorale infection. EBUS being real-time, minimally invasive technique with minimal risk of complications, led to early diagnosis, and prompt treatment. This appears to be a novel diagnostic modality in pulmonary mucormycosis with minimal complications as compared with other biopsy methods with very high complication risk.

19.
ACS Appl Mater Interfaces ; 9(13): 11651-11661, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28290651

RESUMO

Phase tuned quantum confined In2S3 nanocrystals are accessible solvothermally using task-specific ionic liquids (ILs) as structure directing agents. Selective tuning of size, shape, morphology, and, most importantly, crystal phase of In2S3 is achieved by changing the alkyl side chain length, the H-bonding, and aromatic π-stacking ability of the 1-alkyl-3- methylimidazolium bromide ILs, [Cnmim]Br (n = 2, 4, 6, 8, and 10). It is observed that crystallite size is significantly less when ILs are used compared to the synthesis without ILs keeping the other reaction parameters the same. At 150 °C, when no IL is used, pure tetragonal form of ß-In2S3 appears however in the presence of [Cnmim]Br [n = 2,4], at the same reaction condition, a pure cubic phase crystallizes. However, in case of methylimidazolium bromides with longer pendant alkyl chains such as hexyl (C6), octyl (C8) or decyl (C10), nanoparticles of the tetragonal polymorph form. Likewise, judicious choice of reaction temperature and precursors has a profound effect to obtain phase pure and morphology controlled nanocrystals. Furthermore, the adsorption driven catalytic and photocatalytic activity of as-prepared nanosized indium sulfide is confirmed by studying the degradation of crystal violet (CV) dye in the presence of dark and visible light. A maximum of 94.8% catalytic efficiency is obtained for the In2S3 nanocrystals using tetramethylammonium bromide (TMAB) ionic liquid.

20.
Lung India ; 34(1): 88-91, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28144070

RESUMO

Congenital cystic adenomatoid malformations (CCAMs) are rare congenital, nonhereditary developmental anomalies of the lung with unknown etiology. CCAM is predominantly a disorder of infancy with the majority of the cases being diagnosed within the first 2 years of life. When CCAM presents in adults, it represents a diagnostic dilemma and requires careful evaluation. We here report a case of large solitary congenital pulmonary cystic adenomatoid malformation with infection and hemorrhage, which was diagnosed as encysted hydropneumothorax on computerized tomography scans but turned out to be infected pulmonary cystic adenomatoid malformation after surgical excision.

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