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1.
AAPS PharmSciTech ; 25(4): 85, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605158

RESUMO

Cervical cancer (CC) is the fourth leading cancer type in females globally. Being an ailment of the birth canal, primitive treatment strategies, including surgery, radiation, or laser therapy, bring along the risk of infertility, neonate mortality, premature parturition, etc. Systemic chemotherapy led to systemic toxicity. Therefore, delivering a smaller cargo of therapeutics to the local site is more beneficial in terms of efficacy as well as safety. Due to the regeneration of cervicovaginal mucus, conventional dosage forms come with the limitations of leaking, the requirement of repeated administration, and compromised vaginal retention. Therefore, these days novel strategies are being investigated with the ability to combat the limitations of conventional formulations. Novel carriers can be engineered to manipulate bioadhesive properties and sustained release patterns can be obtained thus leading to the maintenance of actives at therapeutic level locally for a longer period. Other than the purpose of CC treatment, these delivery systems also have been designed as postoperative care where a certain dose of antitumor agent will be maintained in the cervix postsurgical removal of the tumor. Herein, the most explored localized delivery systems for the treatment of CC, namely, nanofibers, nanoparticles, in situ gel, liposome, and hydrogel, have been discussed in detail. These carriers have exceptional properties that have been further modified with the aid of a wide range of polymers in order to serve the required purpose of therapeutic effect, safety, and stability. Further, the safety of these delivery systems toward vital organs has also been discussed.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias do Colo do Útero , Feminino , Recém-Nascido , Humanos , Neoplasias do Colo do Útero/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Lipossomos , Hidrogéis
2.
J Ethnopharmacol ; 328: 117991, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38460574

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Glinus oppositifolius (L.) Aug. DC. belongs to the family Molluginaceae, an annual prostrate herb traditionally used to treat inflammations, arthritis, malarial, wounds, fevers, diarrhoea, cancer, stomach discomfort, jaundice, and intestinal parasites. However, the anti-arthritic activity of the aerial part has still not been reported. AIM OF THE STUDY: To investigate the antioxidant and anti-arthritic activity of G. oppositifolius in Complete Freund's Adjuvant (CFA) induced rats. MATERIALS AND METHODS: The dried aerial parts of this plant material were defatted with n-hexane and extracted by methanol using a soxhlet apparatus. The in vitro anti-arthritic activity of methanolic extract of G. oppositifolius (MEGO) was evaluated in protein denaturation, membrane stabilization, and inhibition of proteinase assay at 25, 50, 100, 200, and 400 µg/ml concentrations. Female Wistar rats were immunized sub-dermally into the right hind paw with 0.1 ml of CFA. Rats were administered with MEGO at doses of 200 and 400 mg/kg once daily for fourteen days after arthritis induction. Assessment of arthritis was performed by measuring paw diameter, arthritic index, arthritic score, body weight, organ weight, and hematological and biochemical parameters, followed by the analysis of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin-1-beta (IL-1ß), cyclooxygenase-2 (COX-2), interleukin 13 (IL-13) and interleukin 10 (IL-10) and histopathological study. In vivo antioxidant effect was investigated in enzymatic assays. The presence of phytoconstituents was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) and Liquid Chromatography-Mass Spectrometry (LC-MS), respectively. In silico molecular docking study of the compounds was carried out against COX-2, IL-1ß, IL-6, and TNF-α using AutoDock 4.2 and BIOVIA-Discovery Studio Visualizer software. RESULTS: MEGO's in vitro anti-arthritic activity showed dose-dependent inhibition of protein denaturation, membrane stabilization, and proteinase inhibition, followed by significant in vivo anti-arthritic activity. The rats treated with MEGO showed tremendous potential in managing arthritis-like symptoms by restoring hematological, biochemical, and histological changes in CFA-induced rats. MEGO (200 and 400 mg/kg) showed a significant alleviation in the levels of hyper expressed inflammatory mediators (TNF-α, IL-1ß, and IL-6) and oxidative stress (SOD, CAT, GSH, and LPO) in CFA-induced rats. Spergulagenin-A as identified by LC-MS analysis, exhibited the highest binding affinity against COX-2 (-8.6), IL-1ß (7.2 kcal/mol), IL-6 (-7.4 kcal/mol), and TNF-α (-6.5 kcal/mol). CONCLUSIONS: Provided with the comprehensive investigation, methanolic extract of G. oppositifolius against arthritic-like condition is a proof of concept that revalidates its ethnic claim. The presence of Spergulagenin-A might be responsible for the anti-arthritic activity.


Assuntos
Artrite Experimental , Molluginaceae , Ratos , Animais , Fator de Necrose Tumoral alfa , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Interleucina-6 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ratos Wistar , Ciclo-Oxigenase 2 , Simulação de Acoplamento Molecular , Quimiometria , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Metanol/química , Antioxidantes/uso terapêutico , Interleucina-13 , Peptídeo Hidrolases , Componentes Aéreos da Planta
3.
AAPS PharmSciTech ; 25(3): 57, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472545

RESUMO

Psoriasis is a complex and persistent autoimmune skin disease. The present research focused on the therapeutic evaluation of betulin-loaded nanostructured lipid carriers (BE-NLCs) towards managing psoriasis. The BE-NLCs were synthesized using the emulsification cum solidification method, exhibiting a spherical shape with a particle size of 183.5±1.82nm and a narrow size distribution window (PDI: 0.142±0.05). A high zeta potential -38.64±0.05mV signifies the relative stability of the nano-dispersion system. BE-NLCs show a drug loading and entrapment efficiency of 47.35±3.25% and 87.8±7.86%, respectively. In vitro release study, BE NLCs show a cumulative percentage release of 90.667±5.507% over BE-sol (57.334±5.03%) and BD-oint (42±4.58%) for 720min. In an ex vivo 24-h permeation study, % cumulative amount permeated per cm2 was found to be 55.667±3.33% from BE-NLCs and 32.012±3.26% from BE-sol, demonstrating a better permeability of 21.66% when compared to the standard formulation BD-oint. The in vivo anti-psoriatic activity in the IMQ-induced model shows topical application of BE-sol, BE-NLCs, and BD-oint resulted in recovery rates of 56%, 82%, and 65%, respectively, based on PASI (Psoriasis Area and Severity Index) score. Notably, BE-NLCs demonstrated a more significant reduction in spleen mass, indicating attenuation of the local innate immune system in psoriatic mice. Reductions in TNF-α, IL-6, and IL-17 levels were observed in both BE-sol and BE-NLCs groups compared to the disease control (DC) group, with BE-NLCs exhibiting superior outcomes (74.05%, 44.76%, and 49.26% reduction, respectively). Soy lecithin and squalene-based NLCs could be better carrier system for the improvement of the therapeutic potential of BE towards management of psoriasis.


Assuntos
Ácido Betulínico , Nanoestruturas , Psoríase , Camundongos , Animais , Imiquimode/efeitos adversos , Portadores de Fármacos/uso terapêutico , Psoríase/tratamento farmacológico , Lipídeos , Tamanho da Partícula
4.
AAPS PharmSciTech ; 25(2): 31, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326518

RESUMO

Drug delivery to the buccal mucosa is one of the most convenient ways to treat common mouth problems. Here, we propose a spray-dried re-dispersible mucoadhesive controlled release gargle formulation to improve the efficacy of chlorhexidine. The present investigation portrays an approach to get stable and free-flowing spray-dried porous aggregates of chlorhexidine-loaded sodium alginate nanoparticles. The ionic gelation technique aided with the chlorhexidine's positive surface charge-based crosslinking, followed by spray drying of the nanoparticle's dispersion in the presence of lactose- and leucine-yielded nano-aggregates with good flow properties and with a size range of about 120-350 nm. Provided with the high entrapment efficiency (87%), the particles showed sustained drug release behaviors over a duration of 10 h, where 87% of the released drug got permeated within 12 h. The antimicrobial activity of the prepared formulation was tested on S. aureus, provided with a higher zone of growth inhibition than the marketed formulation. Aided with an appropriate mucoadhesive strength, this product exhibited extended retention of nanoparticles in the throat region, as shown by in vivo imaging results. In conclusion, the technology, provided with high drug retention and extended effect, could be a potential candidate for treating several types of throat infections.


Assuntos
Clorexidina , Faringe , Staphylococcus aureus , Sistemas de Liberação de Medicamentos/métodos , Preparações de Ação Retardada , Antissépticos Bucais , Tamanho da Partícula
5.
Pharm Nanotechnol ; 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38173065

RESUMO

BACKGROUND: Dutasteride is approximately three times more potent than finasteride in treating alopecia. For reducing systemic exposure to dihydrotestosterone (DHT), researchers have shown special interest in developing topical formulations for treating androgenic alopecia. Dutasteride emulsification may lead to good skin penetration and improved availability in different lipophilic skin environments. OBJECTIVES: This study aimed to encapsulate the drug into the lipidic carrier system for better local availability in the scalp skin, develop and evaluate nanoemulgel of dutasteride to ensure efficient topical administration, and perform the in-vivo activity of the developed gel for improved efficacy against alopecia. METHODS: Dutasteride-loaded nanoemulsion was prepared by a high-speed homogenizer, followed by thickening of the dispersion using Carbopol 934. Skin permeation and accumulation were investigated in the excised skin of male Swiss albino mice. The nanoemulgel was characterized based on pH, stress stability, viscosity, and hardness. RESULTS: The optimized dutasteride-loaded nanoemulsion had a size of 252.33 ± 8.59 nm, PDI of 0.205 ± 0.60, and drug content of 98.65 ± 1.78%. Stress stability was performed was well observed in nanoemulsion formulation. Nanoemulgel evaluation results were as follows: pH 5-6 was desirable for topical application, hardness was 43 gm, and spreadability was 79 gm with in vitro release of nanoemulgel at 91.98% and permeation study at 13.67%. CONCLUSION: The in vivo studies demonstrated the growth of newer hair follicles and increased hair diameter and length in dutasteride-loaded nanoemulgel-treated alopecia animals compared to the marketed sample and testosterone-treated group. Provided with the same and long-term storage stability, the developed formulation is supposed to offer a good option for the topical administration of dutasteride in treating androgenic alopecia.

6.
Nanoscale ; 16(5): 2169-2184, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206133

RESUMO

Stimuli-responsive materials have gained significant recent interest owing to their versatility and wide applications in fields ranging from materials science to biology. In the majority of examples, external stimuli, including light, act as a remote source of energy to depolymerize/deconstruct certain nanostructures or provide energy for exploring their functional features. However, there is little emphasis on the creation and precise control of these materials. Although significant progress has been made in the last few decades in understanding the pros and cons of various directional non-covalent interactions and their specific molecular recognition ability, it is only in the recent past that the focus has shifted toward controlling the dimension, dispersity, and other macroscopic properties of supramolecular assemblies. Control over the morphology of supramolecular polymers is extremely crucial not only for material properties they manifest but also for effective interactions with biological systems for their potential application in the field of biomedicine. This could effectively be achieved using photoirradiation which has been demonstrated by some recent reports. The concept as such offers a broad scope for designing versatile stimuli-responsive supramolecular materials with precise structure-property control. However, there has not yet been a compilation that focuses on the present subject of employing light to impact and regulate the morphology of supramolecular polymers or categorize the functional motif for easy understanding. In this review, we have collated recent examples of how light irradiation can tune the morphology and nanostructures of supramolecular polymers and categorized them based on their chemical transformation such as cis-trans isomerization, cycloaddition, and photo-cleavage. We have also established a direct correlation among the structures of the building blocks, mesoscopic properties and functional behavior of such materials and suggested future directions.

7.
J Biomol Struct Dyn ; 42(1): 528-549, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37087726

RESUMO

Multidrug resistance episodes in malaria increased from 3.9% to 20% from 2015 to 2019. Synchronizing the clinical manifestation in chronological sequence led to a unique impression on glucose demand (increased up to 100-fold) by the parasite-infected RBCs. Hence, restriction in the glucose uptake to parasite-infected RBCs could be an alternative approach to conquer the global burden of malaria to a greater extent. A C28 steroidal lactone Withaferin A (WS-3) isolated from Withania somnifera leave extract shows better thermodynamically stable interactions with the glucose transporters (GLUT-1 and PfHT) to standard drugs metformin and lopinavir. MD simulations for a trajectory period of 100 ns reflect stable interactions with the interactive amino acid residues such as Pro141, Gln161, Gln282, Gln283, Trp388, Phe389, and Phe40, Asn48, Phe85, His168, Gln169, Asn311 which potentiating inhibitory activity of WS-3 against GLUT-1 and PfHT respectively. WS-3 was non-hemotoxic (%hemolysis <5%) for a high concentration of up to 1 mg/ml in the physiological milieu. However, the %hemolysis significantly increased up to 30.55 ± 0.929% in a parasitophorous simulated environment (pH 5.0). Increased hemolysis of WS-3 could be due to the production of ROS in an acidic environment. Further, the inhibitory activity of WS-3 against both glucose transporters was supported with flow cytometry-based analysis of parasite-infected RBCs. Results show that WS-3 has low mean fluorescence intensities for both target proteins compared to conventional drugs, suggesting a potential sugar transporter inhibitor against GLUT-1 and PfHT for managing malaria. Communicated by Ramaswamy H. Sarma.


Assuntos
Malária , Withania , Withania/química , Hemólise , Citometria de Fluxo , Malária/tratamento farmacológico , Extratos Vegetais/farmacologia , Glucose/metabolismo
8.
Int J Biol Macromol ; 255: 128212, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989434

RESUMO

Bacterial vaginosis (BV) is a recurring infection that is difficult to treat due to the limited bioavailability of antimicrobials. In this study, Metronidazole (MTZ)-loaded chitosan nanoparticles (MCSNP) were synthesized employing phytic acid (PA) as a crosslinking agent for treating bacterial vaginosis. The prepared MCSNPs were characterized for size, shape, surface charge, compatibility, cytotoxicity, biofilm inhibition, and in-vitro/in-vivo antimicrobial activities. Morphological examination revealed that nanoparticles generated from 0.535 % w/v chitosan and 0.112 % w/v PA were non-spherical, discontinuous, and irregular, with zeta potential ranging from 25.00 ± 0.45 to 39 ± 0.7. The results of DSC and XRD demonstrated no change in the physical state of the drug in the finished formulation. The optimized formulation demonstrates a cumulative drug release of about 98 ± 1.5 % within 8 h. Antimicrobial studies demonstrated that the optimized formulation had enhanced efficacy against acid-adapted BV pathogens, with a MIC value of 0.9 ± 0.1 µg/mL. Compared to the MTZ alone, the in-vivo antibacterial results of in the case of developed nanoparticles showed a four-fold reduction in bacterial count in female Swiss albino mice. Based on the experimental findings, it was concluded that MCSNPs, due to their excellent physiochemical and antibacterial properties, could serve as a potential topical alternative for treating BV.


Assuntos
Quitosana , Nanopartículas , Vaginose Bacteriana , Animais , Feminino , Camundongos , Antibacterianos/química , Quitosana/química , Portadores de Fármacos/química , Metronidazol/farmacologia , Nanopartículas/química , Ácido Fítico , Polieletrólitos , Vaginose Bacteriana/tratamento farmacológico
9.
Microb Pathog ; 186: 106494, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38065294

RESUMO

Bacterial vaginosis (BV) is a recurring, chronic infection that is difficult to treat due to the limited bioavailability of antimicrobials within vaginal epithelial cells. Vaginal administration, because of lower dosing and systemic exposure offers a viable option for treating vaginal infections. In this study, Metronidazole-loaded chitosan nanoparticles were synthesised employing borax (BX) or tannic acid (TA) as an antimicrobial crosslinking agent for treating BV. The prepared NPs were characterized for various physical, physicochemical, pharmaceutical, thermal and antibacterial properties. Morphological investigation revealed that nanoparticles prepared from 0.5 % w/v chitosan, 1.2 % w/v BX, and 0.4 % w/v metronidazole (MTZ) were non-spherical, with particle sizes of 377.4 ± 37.3 nm and a zeta potential of 34 ± 2.1 mV. The optimised formulation has MIC values of 24 ± 0.5 and 59 ± 0.5 µg/mL, against Escherichia coli (E.coli) and Candida albicans (C.albicans) respectively. The results of DSC and XRD demonstrated no change in the physical state of the drug in the finished formulation. Under simulated vaginal fluid, the optimised formulation demonstrates a cumulative drug release of about 90 % within 6h. The prepared borax crosslinked NPs exhibit anti-fungal activities by inhibiting ergosterol synthesis. The in-vivo antibacterial data indicated a comparable reduction in bacterial count compared to the marketed formulation in female Swiss albino mice treated with optimised nanoparticles. According to histopathological findings, the prepared nanoparticle was safe for vaginal use. Based on the experimental findings, it was concluded that MBCSNPs, due to their good physiochemical and antimicrobial properties, could serve as a potential topical alternative for treating BV and reducing fungal infection.


Assuntos
Quitosana , Nanopartículas , Vaginose Bacteriana , Feminino , Humanos , Animais , Camundongos , Metronidazol/farmacologia , Vaginose Bacteriana/tratamento farmacológico , Quitosana/química , Portadores de Fármacos/química , Antibacterianos/química , Nanopartículas/química , Tamanho da Partícula
10.
Assay Drug Dev Technol ; 22(1): 28-39, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38150225

RESUMO

Glycyrrhizin (GL) is the principal constituent of Glycyrrhiza glabra, having antiallergic, anticancer, anti-inflammatory, and antimicrobial action. The reverse-phase high-performance liquid chromatography (RP-HPLC) analytical method was used to quantitatively estimate GL in a nanoformulation and validated as per International Conference on Harmonization Q2 (R1) standards. A stationary phase of the C18-HL reversed-phase column and a mobile phase of acetonitrile and water were used for effective elution. The chromatographic conditions of RP-HPLC were optimized utilizing a quality-by-design approach to accomplish the required chromatographic separation of GL from its nanoformulation with minimal experimental runs. Optimized RP-HPLC conditions for the assay method consist of acetonitrile (41%) and water, pH 1.8, balanced with phosphoric acid (0.1%) as a mobile phase with a flow rate of 1 mL/min. The retention time was found at 7.25 min, and method validation confirmed its sensitivity, preciseness, accuracy, and robustness.


Assuntos
Cromatografia de Fase Reversa , Ácido Glicirrízico , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Acetonitrilas/química , Água
11.
AAPS PharmSciTech ; 24(7): 196, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783948

RESUMO

Despite having a wide range of therapeutic advantages, glycyrrhizin (GL) has few commercial applications due to its poor aqueous solubility. In this study, we combined the benefits of hydroxypropyl ß-cyclodextrin (HP-ßCD) supramolecular inclusion complexes and electrospun nanofibers to improve the solubility and therapeutic potential of GL. A molecular inclusion complex containing GL and HP-ßCD was prepared by lyophilization at a 1:2 molar ratio. GL and hydroxypropyl ß-cyclodextrin inclusion complexes were also incorporated into hyaluronic acid (HA) nanofibers. Prepared NF was analyzed for physical, chemical, thermal, and pharmaceutical properties. Additionally, a rat model of carrageenan-induced hind paw edema and macrophage cell lines was used to evaluate the anti-inflammatory activity of GL-HP-ßCD NF. The DSC and XRD analyses clearly showed the amorphous state of GL in nanofibers. In comparison to pure GL, GL-HP-ßCD NF displayed improved release (46.6 ± 2.16% in 5 min) and dissolution profiles (water dissolvability ≤ 6 s). Phase solubility results showed a four-fold increase in GL solubility in GL-HP-ßCD NF. In vitro experiments on cell lines showed that inflammatory markers like IL-1ß, TNF-α, and IL-6 were significantly lower in GL-HP-ßCD NF compared to pure GL (p < 0.01 and p < 0.05). According to in vivo results, the prepared nanofiber exhibits a better anti-inflammatory effect than pure GL (63.4% inhibition vs 53.7% inhibition). The findings presented here suggested that GL-HP-ßCD NF could serve as a useful strategy for improving the therapeutic effects of GL.


Assuntos
Ácido Glicirrízico , Nanofibras , Ratos , Animais , 2-Hidroxipropil-beta-Ciclodextrina/química , Solubilidade , Ácido Glicirrízico/farmacologia , Nanofibras/química , Anti-Inflamatórios/farmacologia
12.
ACS Appl Mater Interfaces ; 15(43): 50083-50094, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862708

RESUMO

Limited options exist for treatment of periodontitis; scaling and root planing (SRP) are not sufficient to eradicate P. gingivalis and the resulting inflammatory disease. Chlorhexidine (CHX), used as an adjuvant to SRP, may reduce bacterial loads but leads to pain and staining, while evidence for its efficacy is lacking. Antibiotics are effective but can lead to drug-resistance. The rising concern of antibiotic resistance limits the future use of this treatment approach. This study evaluates the efficacy of a novel superhydrophobic (SH) antimicrobial photodynamic therapy (aPDT) device as an adjuvant to SRP for the treatment of periodontitis induced in a Wistar rat in vivo model relative to CHX. The SH-aPDT device comprises an SH silicone rubber strip coated with verteporfin photosensitizer (PS), sterilized, and secured onto a tapered plastic optical fiber tip connected to a red diode laser. The superhydrophobic polydimethylsiloxane (PDMS) strips were fabricated by using a novel soluble template method that creates a medical-grade elastomer with hierarchical surface roughness without the use of nanoparticles. Superhydrophobicity minimizes direct contact of the PS-coated surface with bacterial biofilms. Upon insertion of the device tip into the pocket and energizing the laser, the device generates singlet oxygen that effectively targets and eliminates bacteria within the periodontal pocket. SH-aPDT treatment using 125 J/cm2 of red light on three consecutive days reduced P. gingivalis significantly more than SRP-CHX controls (p < 0.05). Clinical parameters significantly improved (p < 0.05), and histology and stereometry results demonstrated SH-aPDT to be the most effective treatment for improving healing and reducing inflammation, with an increase in fibroblast cells and extracellular matrix and a reduction in vascularization, inflammatory cells, and COX-2 expression. The SH-aPDT approach resulted in complete disease clearance assessed 30 days after treatment initiation with significant reduction of the periodontal pocket and re-formation of the junctional epithelium at the enamel-cementum junction. PS isolation on a SH strip minimizes the potential for bacteria to develop resistance, where the treatment may be aided by the oxygen supply retained within the SH surface.


Assuntos
Anti-Infecciosos , Periodontite , Fotoquimioterapia , Ratos , Animais , Ratos Wistar , Bolsa Periodontal/tratamento farmacológico , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Fotoquimioterapia/métodos , Anti-Infecciosos/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Terapia Combinada , Clorexidina , Interações Hidrofóbicas e Hidrofílicas
13.
ACS Phys Chem Au ; 3(4): 348-357, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37520319

RESUMO

Lead halide perovskite nanocrystals have received significant attention as an absorber material for designing efficient optoelectronic devices. The fundamental understanding of the hot carrier (HC) dynamics as well as its extraction in hybrid systems is essential to further boost the performance of solar cells. Herein, we have explored the electron transfer dynamics in the CsPbBr3-Au144 cluster hybrid using ultrafast transient absorption spectroscopy. Our analysis reveals faster HC cooling time (from 515 to 334 fs) and a significant drop in HC temperature from 1055 to 860 K in hybrid, suggesting the hot electron transfer from CsPbBr3 nanocrystals to the Au nanoclusters (NCs). Eventually, we observe a much faster hot electron transfer compared to the band-edge electron transfer, and 45% hot-electron transfer efficiency was achieved at 0.64 eV, above band-edge photoexcitation. Furthermore, the significant enhancement of the photocurrent to the dark current ratio in this hybrid system confirms the charge separation via the electron transfer from CsPbBr3 nanocrystals to Au144 NCs. These findings on HC dynamics could be beneficial for optoelectronic devices.

14.
Langmuir ; 39(31): 11134-11144, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37497839

RESUMO

Although silica surfaces have been used in organic oxidations for the production of peroxides, studies of airborne singlet oxygen at interfaces are limited and have not found widespread advantages. Here, with prenyl phenol-coated silica and delivery of singlet oxygen (1O2) through the gas phase, we uncover significant selectivity for dihydrofuran formation over allylic hydroperoxide formation. The hydrophobic particle causes prenyl phenol to produce an iso-hydroperoxide intermediate with an internally protonated oxygen atom, which leads to dihydrofuran formation as well as O atom transfer. In contrast, hydrophilic particles cause prenyl phenol to produce allylic hydroperoxide, due to phenol OH hydrogen bonding with SiOH surface groups. Mechanistic insight is provided by air/nanoparticle interfaces coated with the prenyl phenol, in which product yield was 6-fold greater on the hydrophobic nanoparticles compared to the hydrophilic nanoparticles and total rate constants (ASI-kT) of 1O2 were 13-fold greater on the hydrophobic vs hydrophilic nanoparticles. A slope intersection method was also developed that uses the airborne 1O2 lifetime (τairborne) and surface-associated 1O2 lifetime (τsurf) to quantitate 1O2 transitioning from volatile to non-volatile and surface boundary (surface···1O2). Further mechanistic insights on the selectivity of the reaction of prenyl phenol with 1O2 was provided by density functional theory calculations.

15.
Curr Pharm Des ; 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37246329

RESUMO

BACKGROUND: Viral disease is a well-known cause of a significant impact on economic losses and threatens developed and developing societies. High mutation rates and the lack of ability of conventional formulations to target specific cells pose substantial hurdles to the successful treatment of viral diseases.

Methods: We conducted a preliminary search by a standard procedure. With hand searching, we conducted an advanced search across several electronic databases. After defining the selection criteria, two writers independently reviewed and evaluated the first 500 abstracts before screening the remaining 300. Since there was 97% agreement on the screening decisions, only one reviewer conducted the screening. The pre-planned data extraction process was accomplished, and the thoroughness of the description of participation techniques was assessed. Additional data extraction was carried out for articles with the most detailed illustrations. Four stakeholder representatives co-authored this systematic review.

Results: Incorporating selective carbohydrate polymers into the antiviral pharmaceutical compositions could help to manage biological complications associated with viral infections. We included 172 papers in which authors were involved in a systematic review. The present review explains the role of carbohydrate polymers (chitosan, carrageenan, alginate, cyclodextrin, dextran, and heparin) in the prevention and treatment of viral infections in terms of their source, molecular weight, surface charge, chemical composition, and structure. Additionally, the review describes the primary mechanism of drug delivery performance of carbohydrate polymers to improve the antiviral properties and pharmacokinetic behaviour of lamivudine, zidovudine, acyclovir, etc.

Conclusion: The article discussed the role of carbohydrate polymers in mitigating virus-induced associated complications like bacterial infection, cardiovascular disorder, oxidative stress, and metabolic disorder. As a result, this work will provide valuable information to scientists, researchers, and clinicians for suitable carbohydrate polymer-based pharmaceutical development.

16.
Angew Chem Int Ed Engl ; 62(17): e202218555, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36828774

RESUMO

After more than three decades of extensive investigations on supramolecular polymers, strategies for self-limiting growth still remain challenging. Herein, we exploit a new V-shaped monomer design to achieve anticooperatively formed oligomers with superior robustness and high luminescence. In toluene, the monomer-oligomer equilibrium is shifted to the monomer side, enabling the elucidation of the molecular packing modes and the resulting (weak) anticooperativity. Steric effects associated with an antiparallel staircase organization of the dyes are proposed to outcompete aromatic and unconventional B-F⋅⋅⋅H-N/C interactions, restricting the growth at the stage of oligomers. In methylcyclohexane (MCH), the packing modes and the anticooperativity are preserved; however, pronounced solvophobic and chain-enwrapping effects lead to thermally ultrastable oligomers. Our results shed light on understanding anticooperative effects and restricted growth in self-assembly.

17.
Clin Case Rep ; 11(2): e6926, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36789296

RESUMO

Atypical presentations may be presented with the common symptoms in Dengue. We, hereby, present a case of Dengue who was admitted in our hospital with the complaints of fever, upper abdominal pain, and vomiting, literally diagnosed as a case of acute pancreatitis.

18.
Biomed Chromatogr ; 37(4): e5588, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36698254

RESUMO

Dextromethorphan (DM) and its metabolite dextrorphan (DX) continue to draw the attention of researchers owing to their diverse pharmacodynamics. Thus, there are possibilities for repurposing DM. Most of the pharmacodynamics of DM needs further validation in different preclinical models. Also, it is necessary to correlate the pharmacodynamics with relevant pharmacokinetics data. Multiple bioanalytical techniques developed for this purpose primarily use a high sample processing volume. Since sample volume is a limiting factor for many preclinical models, an effort was taken to develop an alternative method suitable for handling low sample processing volumes. An efficient solid-phase extraction technique, robust liquid chromatographic (LC) separation and highly sensitive tandem mass spectrometric detection (MS/MS) showed suitability for use of a 30 µl sample processing volume. This led to the development of a highly specific, selective, accurate and precise-bio-analytical method for simultaneous quantification of DM and DX in rat plasma. The validated method was linear in the range of 0.196-403.356 ng/ml for DM and 0.102-209.017 ng/ml for DX. The application of the method was demonstrated through the estimation of pharmacokinetic parameters that showed good congruence with earlier studies.


Assuntos
Dextrometorfano , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Dextrometorfano/farmacocinética , Cromatografia Líquida , Dextrorfano/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Manejo de Espécimes , Reprodutibilidade dos Testes
19.
J Drug Target ; 31(4): 354-368, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36604804

RESUMO

Malaria is a life-threatening parasitic disease transmitted by the infected female Anopheles mosquito. The development of drug tolerance and challenges related to the drugs' pharmacodynamic and pharmacokinetic parameters limits the antimalarial therapeutics response. Currently, nanotechnology-based drug delivery system provides an integrative platform for antimalarial therapy by improving the drug physicochemical properties, combating multidrug resistance, and lowering antimalarial drug-related toxicity. In addition, surface engineered nanocarrier systems offer a variety of alternatives for site-specific/targeted delivery of antimalarial therapeutics, anticipating better clinical outcomes at low drug concentrations and low toxicity profiles, as well as reducing the likelihood of the emergence of drug resistance. So, constructing nano carrier-based approaches for drug delivery has been considered the foremost strategy to combat malaria. This review focuses on the numerous nanotherapeutic strategies utilised to treat malaria as well as the benefits of nanotechnology as a potentially effective therapeutic.


Assuntos
Antimaláricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Malária , Animais , Feminino , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Nanomedicina , Malária/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Resistência a Medicamentos
20.
J Biomol Struct Dyn ; 41(11): 4993-5006, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35585777

RESUMO

According to the 2021 Malaria report, 241 million clinical episodes with 627000 deaths penalty was estimated across the worldwide. However, mutation in the propeller domain of Plasmodium falciparum kelch 13 protein resulted in longer parasite clearance time following an artemisinin-based treatment and had a greater survival rate of ring-stage parasites even after a brief exposure to a high dose of artesunate. Clinical manifestations become more complex and worse with the emerging trend of drug resistance against artemisinin derivatives and the poor effectiveness of malaria vaccination drive. Steroidal lactone (withanolide) moiety (C-28) isolated from methanolic leaf extract Withania somnifera show a greater affinity towards Pfkelch 13 protein in comparison to the artemisinin derivatives (artesunate, artemether). The isolated compound was characterized to be withaferin A with a percentage yield of 29.01% w/w in chloroform fraction, 1.75% w/w in methanolic extract, and 0.29% w/w in raw leaf powder. Structure-based analysis shows that withaferin A (docking score -8.253, -9.802) has a higher affinity for two distinct binding pockets I and II of the Plasmodium falciparum kelch 13 protein than artesunate (docking score -4.470, -3.656). Further, Gibbs binding free energy signifies thermodynamic stability of the docked complex of withaferin A (-43.25, -43.76 Kcal/mol) in comparison to artesunate docked complex (-8.49, -5.75 Kcal/mol). The pharmacokinetic profile of withaferin A shows more drug-likeness characteristics without violating Jorgensen's rule of three, and Lipinski's rule of five. Hence above experimental findings suggest withaferin A could be a suitable therapeutic adjunct for preclinical evaluation of antimalarial potentiality in artemisinin-resistant malaria. HIGHLIGHTsMalaria is a life-threatening parasitic disease caused by Plasmodium species.The emerging trend of artemisinin resistance and severe side effects (CNS and cardiotoxicity) are the potential challenges faced by antimalarial therapeutics.Artemisinin-mimic potentiality (ROS-mediated antiparasitic activity) of withaferin A shows a strong affinity towards artemisinin resistance Plasmodium falciparum kelch 13 protein.The pharmacokinetic profiling of the withaferin A signifies its drug-likeness characteristics without violating Jorgensen's rule of three, and Lipinski's rule of five.Based on molecular docking and pharmacokinetic profiling, withaferin A could be a suitable therapeutic adjunct for preclinical investigation of antimalarial potentiality in artemisinin-resistant malaria.Communicated by Ramaswamy H. Sarma.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Withania , Antimaláricos/farmacologia , Plasmodium falciparum , Artesunato/farmacologia , Artesunato/uso terapêutico , Simulação de Acoplamento Molecular , Malária Falciparum/tratamento farmacológico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Malária/tratamento farmacológico
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