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1.
J Phys Chem Lett ; 15(32): 8211-8217, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39101701

RESUMO

We leveraged strong light-matter coupling, a quantum process generating hybridized states, to prepare phototransistors using donor-acceptor pairs that transfer energy via Rabi oscillations. In a prototype experiment, we used a cyanine J-aggregate (TDBC; donor) and MoS2 monolayer (acceptor) in a field effect transistor cavity to study photoresponsivity. Energy migrates through the newly formed polaritonic ladder, with enhanced device efficiency when the cavity is resonant with donors. A theoretical model based on the time-dependent Schrödinger equation helped interpret results, with polaritonic states acting as a strong energy funnel to the MoS2 monolayer. These findings suggest novel applications of strong light-matter coupling in quantum materials.

2.
Mol Divers ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709459

RESUMO

Malaria caused by P. falciparum, has been recognized as one of the major infectious diseases causing the death of several patients as per the reports from the World Health Organization. In search of effective therapeutic agents against malaria, several research groups have started working on the design and development of novel heterocycles as anti-malarial agents. Heterocycles have been recognized as the pharmacophoric features for the different types of medicinally important activities. Among all these heterocycles, nitrogen containing aza-heterocycles should not be underestimated owing to their wide therapeutic window. Amongst the aza-heterocycles, indoles and fused indoles such as marinoquinolines, isocryptolepines and their regioisomers, manzamines, neocryptolenines, and indolones have been recognized as anti-malarial agents active against P. falciparum. The present work unleashes the synthetic attempts of anti-malarial indoles and fused indoles through cyclocondensation, Fischer-indole synthesis, etc. along with the brief discussions on structure-activity relationships, in vitro or in vivo studies for the broader interest of these medicinal chemists, working on their design and development as potential anti-malarial agents.

3.
Animals (Basel) ; 14(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38791681

RESUMO

This paper presents the demographics, dynamics, and attitudes of dog ownership across three states in India. The background of this research is set against the increasing significance of pet ownership in urban Indian contexts, with a particular focus on understanding the variations in dog-ownership patterns and their implications for public health and animal welfare. We employed a survey-based approach, gathering quantitative survey data from dog owners (n = 563) and non-dog-owners (n = 9282) across different socioeconomic and geographic backgrounds in seven Indian settlements. The results reveal notable differences in dog-ownership patterns, influenced by regional state. In particular, settlements in Gujarat were found to have significantly fewer dog-owning households than those in Tamil Nadu, with no differences found according to settlement size. Dog ownership was found to be more common in households of higher socioeconomic standing, and settlements in Uttarakhand were found more frequently to possess dogs for reasons other than companionship. Data from Ahmedabad and Vadodara, specifically, also indicate rapidly increasing rates of pet ownership. Sterilisation and rabies vaccination proportions were typically low and high, respectively, across all settlements, with few significant differences found among settlements. Confinement of owned dogs at night was significantly lower in Nainital than all other settlements. Differences in attitudes towards roaming dogs between dog owners and non-dog-owners were also examined, with the results indicating both positive and negative trends accordingly. Our results emphasise the need for region-specific strategies in public health and animal welfare policies, acknowledging the diverse nature of pet ownership in India. This research provides valuable insight for policymakers and animal welfare organisations, underlining the importance of tailored approaches to address the unique challenges and opportunities in the Indian context.

4.
Phytochem Anal ; 35(5): 1207-1220, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38634333

RESUMO

INTRODUCTION: Rhododendron arboreum Sm. flowers grow in the Himalayan region and have traditionally been used in beverages and food. These wild edible Himalayan flowers are known for their sweet-sour flavor and beautiful scarlet red color. The primary pigments responsible for the scarlet red color of these flowers are anthocyanins. OBJECTIVE: In the present study, we conducted chemo-profiling and elucidated the chromatic characteristics of R. arboreum flower petals growing in the wild in different altitudinal areas. METHODOLOGY: The content of anthocyanins, phenolics, and other flavonoids was determined in R. arboreum flower petals collected from 38 different locations in two provinces in India (Himachal Pradesh and Uttarakhand) to obtain a distinguishable chemical index. A UHPLC method has also been developed and validated for the quantitative analysis. Besides, the color characteristics of each collected floral sample were also analyzed. RESULTS: Chemometric analysis (principal component analysis [PCA] and heatmap analysis) revealed that floral samples collected from different altitudes exhibited similar chemical diversity, whereas statistical analysis (bivariate linear correlation) revealed a positive correlation between the color parameter a*/b* and cyanidin glycosides. Besides, non-targeted metabolomics analysis was carried out, which resulted in the tentative identification of 150 metabolites. CONCLUSION: The results revealed that there is a direct influence of accumulated anthocyanins to color parameter a*/b* values in the floral samples irrespective of altitude.


Assuntos
Altitude , Antocianinas , Flores , Polifenóis , Análise de Componente Principal , Rhododendron , Rhododendron/química , Flores/química , Polifenóis/análise , Cromatografia Líquida de Alta Pressão , Antocianinas/análise , Cor , Flavonoides/análise
5.
Nano Lett ; 23(11): 5004-5011, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37235844

RESUMO

Strong light-matter coupling offers a way to tailor the optoelectronic properties of materials. Energy transfer between strongly coupled donor-acceptor pairs shows remarkable efficiency beyond the Förster distance via coupling through a confined photon. This long-range energy transfer is facilitated through the collective nature of polaritonic states. Here, the cooperative, strong coupling of a donor (MoS2 monolayer) and an acceptor (BRK) generates mixed polaritonic states. The photocurrent spectrum of the MoS2 monolayer is measured in a field effect transistor while coupling the two oscillators to the confined cavity mode. The strongly coupled system shows efficient energy transfer, which is observed through the photoresponsivity even the donor and acceptor are physically separated by 500 Å. These studies are further correlated with the Hopfield coefficients and the overlap integral of the lower polaritonic and uncoupled/dark states. Cavity detuning and distance-dependent studies support the above evidence. These observations open new avenues for using long-range interaction of polaritonic states in optoelectronic devices.

6.
J Ethnopharmacol ; 300: 115714, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36113678

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Swertia chirayita (Roxb.) H. Karst. is a traditionally used, well-recognized medicinal plant of the family Gentianaceae with significant therapeutic potential. It has been traditionally used to cure various ailments such as fever, vomiting, jaundice, digestive disorders, heart diseases, diabetes, malaria, scorpion bite, and skin diseases. AIM OF REVIEW: The present review emphasized the traditional uses, phytochemistry, pharmacology, toxicology, chemical profiling, and structural identification of isolated compounds by analytical and spectroscopic techniques. This review demonstrates the possibility of advanced ethnopharmacological research. MATERIALS AND METHODS: The literature on S. chirayita was obtained from bibliographic databases like Web of Science, PubMed, Science-Direct, American Chemical Society (ACS), Google Scholar, and SciFinder. The compiled review is covered up until March 2022. RESULTS: Approximately, 123 specialized metabolites including xanthones, seco-iridoids, terpenoids, alkaloids, and flavonoids have been isolated and characterized from S. chirayita. The extract and isolated compounds exhibited a wide spectrum of pharmacological effects such as anti-inflammatory, antioxidant, antitumor, hepatoprotective, antiviral, antimalarial, and antibacterial offering scientific evidence for traditional claims of this medicinal plant. In addition, various analytical methods using HPTLC, UPLC, HPLC, LC-MS, and GC-MS have also been documented to determine the phytochemicals of S. chirayita. CONCLUSION: The current article provides information on traditional usage, phytochemistry, chemical profiling, structure elucidation, pharmacological efficacy, toxicity, and future prospects of S. chirayita. This plant has long been traditionally used in a variety of ways by indigenous people. Numerous phytoconstituents and several pharmacological activities have been reported in S. chirayita. However, there are still some scientific gaps such as identification of bioactive compounds, structure-activity relationship and mechanistic action of isolated bioactive compounds, development of effective analytical methods for comprehensive quality control, and safety profiles that need to be addressed.


Assuntos
Antimaláricos , Plantas Medicinais , Swertia , Xantonas , Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , Antioxidantes , Antivirais , Etnofarmacologia , Flavonoides , Humanos , Iridoides , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Terpenos
7.
ACS Nano ; 15(8): 13616-13622, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34347448

RESUMO

Strong light-matter interaction of functional materials is emerging as a promising area of research. Recent experiments suggest that material properties like charge transport can be controlled by coupling to a vacuum electromagnetic field. Here, we explored the design of a Fabry-Perot cavity in a field-effect transistor configuration and studied the charge transport in two-dimensional materials. The optical and electrical measurements of strongly coupled WS2 suggest an enhancement of electron transport at room temperature. Electron mobility is enhanced more than 50 times at ON resonance conditions. Similarly, Ion/Ioff ratio of the device increased by 2 orders of magnitude without chemical modification of the active layer. Cavity tuning and coupling strength-dependent studies support the evidence of modifying the electronic properties of the coupled system. A clear correlation in the effective mass of the polaritonic state and Schottky barrier height indicates a collective nature of light-matter interaction.

8.
Brain Sci ; 9(11)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31717715

RESUMO

OBJECTIVE: Brain damage, long-term disability and death are the dreadful consequences of ischemic stroke. It causes imbalance in the biochemical constituents that distorts the brain dynamics. Understanding the sub-cellular alterations associated with the stroke will contribute to deeper molecular understanding of brain plasticity and recovery. Current routine approaches examining lipid and protein biochemical changes post stoke can be difficult. Fourier Transform Infrared (FTIR) imaging spectroscopy can play a vital role in detecting these molecular alterations on a sub-cellular level due to its high spatial resolution, accuracy and sensitivity. This study investigates the biochemical and molecular changes in peri-infract zone (PIZ) (contiguous area not completely damaged by stroke) and ipsi-lesional white matter (WM) (right below the stroke and PIZ regions) nine weeks post photothrombotic ischemic stroke in rats. MATERIALS AND METHODS: FTIR imaging spectroscopy and transmission electron microscopy (TEM) techniques were applied to investigate brain tissue samples while hematoxylin and eosin (H&E) stained images of adjacent sections were prepared for comparison and examination the morphological changes post stroke. RESULTS: TEM results revealed shearing of myelin sheaths and loss of cell membrane, structure and integrity after ischemic stroke. FTIR results showed that ipsi-lesional PIZ and WM experienced reduction in total protein and total lipid content compared to contra-lesional hemisphere. The lipid/protein ratio reduced in PIZ and adjacent WM indicated lipid peroxidation, which results in lipid chain fragmentation and an increase in olefinic content. Protein structural change is observed in PIZ due to the shift from random coli and α-helical structures to ß-sheet conformation. CONCLUSION: FTIR imaging bio-spectroscopy provide novel biochemical information at sub-cellular levels that be difficult to be obtained by routine approaches. The results suggest that successful therapeutic strategy that is based on administration of anti-oxidant therapy, which could reduce and prevent neurotoxicity by scavenging the lipid peroxidation products. This approach will mitigate tissue damage in chronic ischemic period. FTIR imaging bio-spectroscopy can be used as a powerful tool and offer new approach in stroke and neurodegenerative diseases research.

9.
Am J Physiol Cell Physiol ; 317(6): C1289-C1303, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553649

RESUMO

Glycogen synthase kinase-3 (GSK-3) is a multitasking protein kinase that regulates numerous critical cellular functions. Not surprisingly, elevated GSK-3 activity has been implicated in a host of diseases including pathological inflammation, diabetes, cancer, arthritis, asthma, bipolar disorder, and Alzheimer's. Therefore, reagents that inhibit GSK-3 activity provide a means to investigate the role of GSK-3 in cellular physiology and pathophysiology and could become valuable therapeutics. Finding a potent inhibitor of GSK-3 that can selectively target this kinase, among over 500 protein kinases in the human genome, is a significant challenge. Thus there remains a critical need for the identification of selective inhibitors of GSK-3. In this work, we introduce a novel small organic compound, namely COB-187, which exhibits potent and highly selective inhibition of GSK-3. Specifically, this study 1) utilized a molecular screen of 414 kinase assays, representing 404 unique kinases, to reveal that COB-187 is a highly potent and selective inhibitor of GSK-3; 2) utilized a cellular assay to reveal that COB-187 decreases the phosphorylation of canonical GSK-3 substrates indicating that COB-187 inhibits cellular GSK-3 activity; and 3) reveals that a close isomer of COB-187 is also a selective and potent inhibitor of GSK-3. Taken together, these results demonstrate that we have discovered a region of chemical design space that contains novel GSK-3 inhibitors. These inhibitors will help to elucidate the intricate function of GSK-3 and can serve as a starting point for the development of potential therapeutics for diseases that involve aberrant GSK-3 activity.


Assuntos
Compostos de Bifenilo/farmacologia , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Animais , Compostos de Bifenilo/síntese química , Desenho de Fármacos , Ensaios Enzimáticos , Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Fosforilação , Inibidores de Proteínas Quinases/síntese química , Proteínas Quinases/genética , Células RAW 264.7 , Relação Estrutura-Atividade , Especificidade por Substrato , Células THP-1 , Acetato de Tetradecanoilforbol/farmacologia , Tiadiazóis/química , Tiadiazóis/farmacologia
10.
Natl J Maxillofac Surg ; 10(1): 27-32, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31205385

RESUMO

BACKGROUND AND OBJECTIVE: Oral submucous fibrosis (OSMF) is a precancerous condition. It is widespread in the Asian subcontinent, with India bearing most of the burden. It is characterized by mucosal rigidity of varying intensity due to the fibroelastic changes of the juxta epithelial layer, resulting in a progressive inability to open the mouth. Early recognition with accurate staging of the disease and appropriate treatment planning is of utmost importance to prevent the malignant transformation and to improve the quality of life of the patient. In the present study, an attempt is made to clinically evaluate the condition and correlate it with the histopathological findings according to standard criteria. MATERIALS AND METHODS: A hospital-based study was conducted on sixty OSMF patients. Detailed history was recorded, and functional staging was given depending on mouth opening. Punch biopsy was performed, and histological stages were given based on standard criteria. The data so received were mathematically evaluated to determine whether any correlation exists between the stages using Chi-square test. RESULTS: The sixty patients were in the age range of 16-50 years. Male-to-female ratio was that of 97:3. The statistical analysis using Chi-square test showed statistically significant association (P < 0.001) between the functional and histologic stages. CONCLUSION: There is a definite correlation between functional and histological stages of OSMF which suggests that clinically advanced OSMF has extensive fibrosis histologically.

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