Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Microencapsul ; 41(6): 403-418, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39007845

RESUMO

OBJECTIVE: The main purpose of the present study was to evaluate the therapeutic efficacy of Aloe vera-coated curcumin encapsulated nanoparticles in mitigating Alzheimer's disease progression in mice, by examining behavioural changes, biochemical markers, and histopathological alterations, thus elucidating its potential as a treatment strategy. METHODS: The green synthesis method was used to synthesise this nanoformulation, which was then characterised using a variety of techniques, including percentage encapsulation efficacy, UV-visible spectroscopy, DLS, FT-IR, FESEM, and EDX. Several in-vivo assessments, including behavioural evaluations, dose optimisation studies, oxidative stress marker estimation, and histological studies, were conducted to determine the potential therapeutic impact of nanoformulation on the Alzheimer-induced mice model. RESULTS: The synthesised nanoparticles show a mean diameter of 76.12 nm ±1.23, a PDI of 0.313 ± 0.02, a zeta potential of 6.27 ± 0.65 mV, and the percentage encapsulation efficiency between 90% and 95% indicating good stability of synthesised nanoformulation. With the help of Morris water maze, Y-maze, and novel object recognition assay, the learning capacity and memory were assessed, and the results show that the synthesised nanoformulation significantly decreased the transfer latency to reach baited arm or to the hidden platform within 7 days. CONCLUSION: The formulation demonstrated significant biochemical benefits and remarkable cognitive advantages, establishing it as a prospective therapeutic intervention option that is both safe and effective.


Assuntos
Aloe , Doença de Alzheimer , Curcumina , Modelos Animais de Doenças , Nanopartículas , Animais , Curcumina/farmacologia , Curcumina/administração & dosagem , Curcumina/química , Aloe/química , Doença de Alzheimer/tratamento farmacológico , Camundongos , Nanopartículas/química , Masculino , Comportamento Animal/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos
2.
Cutan Ocul Toxicol ; 43(3): 211-226, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39024063

RESUMO

The process of skin ageing is a natural biological phenomenon characterised by the emergence of wrinkles, age spots, sagging skin, and dryness over time. The increasing significance of skin in physical attractiveness has heightened skincare concerns. Anti-ageing cosmetics play a pivotal role in nurturing the skin, enhancing its quality, and promoting overall health. Today, cosmetics have evolved beyond mere aesthetics and are now integral to individual wellness. The contemporary quest for perpetual youth has intensified, prompting a deeper exploration into the skin ageing process. This comprehensive exploration delves into various elements involved in skin ageing, encompassing cells such as stem and endothelial cells, blood vessels, soft tissues, and signalling pathways. The molecular basis of skin ageing, including biochemical factors like reactive oxygen species, damaged DNA, free radicals, ions, and proteins (mRNA), is scrutinised alongside relevant animal models. The article critically analyzes the outcomes of utilising herbal components, emphasising their advantageous anti-ageing properties. The factors contributing to skin ageing, mechanistic perspectives, management approaches involving herbal cosmeceutical, and associated complications (especially cardiovascular diseases, Parkinson's, Alzheimer's, etc.) are succinctly addressed. In addition, the manuscript further summarises the recent patented innovations and toxicity of the herbal cosmeceuticals for anti-ageing and ageing associated disorders. Despite progress, further research is imperative to unlock the full potential of herbal components as anti-ageing agents.


Assuntos
Cosmecêuticos , Envelhecimento da Pele , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Cosmecêuticos/uso terapêutico , Animais , Cosméticos , Pele/efeitos dos fármacos , Pele/patologia , Pele/metabolismo , Preparações de Plantas/uso terapêutico , Preparações de Plantas/farmacologia
3.
Opt Lett ; 48(2): 307-310, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638444

RESUMO

Laser-driven hypervelocity impact experiments were used to study pressure-induced long-term effects on the crystal structure of undoped GaSb. X-ray diffraction and confocal micro-Raman spectra were collected on unshocked and shock-compressed samples, with corresponding pressures ranging between 8 and 23 GPa. GaSb retained bulk crystallinity at 8 GPa but showed localized site disordering, transformed into an amorphous state at 13 GPa, and stayed in that phase until 23 GPa.

4.
Opt Lett ; 47(8): 1953-1955, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427309

RESUMO

Using GaAs as a test material, we investigated the redshift between emission and the optical bandgap. The knowledge of the energy difference, referred to as the Stokes shift, is of considerable importance for solid-state light sources because its magnitude defines the centered monochromaticity of the emission. Employing Fan's theory, we reveal the basic parameters, which determine the Stokes shift, and provide an uncertainty analysis, considering both uncorrelated and correlated variables. We disclose that the considerable scatter of the dielectric constants in the literature causes uncertainties comparable to or even exceeding the mean. The work stresses that the high-frequency and static dielectric constants might be closer than the currently promoted numbers.

5.
Opt Lett ; 40(11): 2580-3, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26030562

RESUMO

The intrinsic photoluminescence Stokes shift, i.e., the energy difference between optical band gap and emission peak, of 350 µm thick semi-insulating GaAs wafers is found to be 4 meV at room temperature. The result is based on the determination of the optical bulk band gap from the transmission trend via modified Urbach rule whose result is confirmed with the transmission derivative method. The findings reveal the detailed balance of the optically evoked transitions and disclose the intrinsic link between Stokes shift and the Urbach tail slope parameter.

6.
Micromachines (Basel) ; 15(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38258230

RESUMO

A set of polymer-embedded, two-colored nanocomposites were prepared where the co-existing emission peaks (~578 nm and ~650 nm) had different ratios at their emission thresholds. The nanocomposite samples were simultaneously excited by a 405 nm laser, and the growth of photoluminescence intensities was studied as a function of excitation intensity. The two peaks showed different growth evolution mechanisms. The factors impacting this difference could be (1) energy transfer between the two sized nanoparticles; (2) relaxation mechanism of smaller nanoparticles; and (3) material properties of the polymer.

7.
Int J Biol Macromol ; 279(Pt 4): 135418, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245103

RESUMO

Diabetic wounds have become a serious global health concern, with a growing number of patients each year. Diabetic altered wound healing physiology, as well as resulting complications, make therapy difficult. Hence, diabetic wound healing necessitates a multidisciplinary strategy. This study focused on the formulation, statistical optimization, ex vivo, and in vitro evaluation of a diabetic wound healing by n-acetyl cysteine (NAC) loaded hydrogel. The objective of the study is to formulate n-acetyl loaded hydrogel with different ratio (1:1, 1:2, 1:3, 2:1) of sodium alginate and guar gum. The antibacterial and antifungal assessment against the viability of Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli), and Staphylococcus aureus (S.aureus) and Candida albicans (C. albicans) was conducted after determining the in vitro drug release profile. The results of the experiment demonstrated that the formulation F3 was an optimal formulation on triplicate measurement with a pH of 6.2 ± 0.168, and a density of 1.026 ± 0.21. In vitro cell line study exhibited F3 has potential role in cell adhesion and proliferation might be beneficial to tissue regeneration and wound healing. The results imply that F3 may be helpful for the quick healing of diabetic wounds by promoting angiogenesis and also by scavenging free oxygen radicals.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39005131

RESUMO

Drug delivery through the blood-brain barrier (BBB) is one of the key challenges in the modern era of medicine due to the highly semipermeable characteristics of BBB that restrict the entry of various drugs into the central nervous system (CNS) for the management of brain disorders. Drugs can be easily incorporated into carbon nanocarriers that can cross the bloodbrain barrier. Numerous nanocarriers have been developed, including polymeric nanoparticles, carbon nanoparticles, lipid-based nanoparticles, etc. Among these, carbon nanostructures could be superior due to their easier BBB penetration and strong biocompatibility. Several CDs (Carbon dots) and CD-ligand conjugates have explored effectively penetrating the BBB, which enables significant progress in using CD-based drug delivery systems (DDS) to manage CNS diseases. Despite the drug delivery applications, they might also be used as a central nervous system (CNS) drug; few of the carbon nanostructures show profound neurodegenerative activity. Further, their impact on neuronal growth and anti- amyloid action is quite interesting. The present study covers diverse carbon nanostructures for brain-targeted drug delivery, exploring a variety of CNS activities. Moreover, it emphasizes recent patents on carbon nanostructures for CNS disorders.

9.
Eur J Pharmacol ; 981: 176906, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39154829

RESUMO

Silymarin, a bioflavonoid derived from the Silybum marianum plant, was discovered in 1960. It contains C25 and has been extensively used as a therapeutic agent against liver-related diseases caused by alcohol addiction, acute viral hepatitis, and toxins-inducing liver failure. Its efficacy stems from its role as a potent anti-oxidant and scavenger of free radicals, employed through various mechanisms. Additionally, silymarin or silybin possesses immunomodulatory characteristics, impacting immune-enhancing and immune-suppressive functions. Recently, silymarin has been recognized as a potential neuroprotective therapy for various neurological conditions, including Parkinson's and Alzheimer's diseases, along with conditions related to cerebral ischemia. Its hepatoprotective qualities, primarily due to its anti-oxidant and tissue-regenerating properties, are well-established. Silymarin also enhances health by modifying processes such as inflammation, ß-amyloid accumulation, cellular estrogenic receptor mediation, and apoptotic machinery. While believed to reduce oxidative stress and support neuroprotective mechanisms, these effects represent just one aspect of the compound's multifaceted protective action. This review article further delves into the possibilities of potential therapeutic advancement of silymarin and silibinin for the management of neurodegenerative disorders via mechanics modules.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Silibina , Silimarina , Humanos , Silibina/farmacologia , Silibina/uso terapêutico , Silimarina/uso terapêutico , Silimarina/farmacologia , Animais , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos
10.
Nanomaterials (Basel) ; 13(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36903749

RESUMO

Saturable absorption in perovskite quantum dot (PQD) films, leading to saturation in photoluminescence (PL), is reported. PL of drop-casting films was used to probe how excitation intensity and host-substrate influence the growth of PL intensity. The PQD films were deposited on single-crystal GaAs, InP, Si wafers and glass. Saturable absorption was confirmed through PL saturation in all films, with different excitation intensity thresholds, suggesting strong substrate-dependent optical properties, resulting from absorption nonlinearities in the system. The observations extend our former studies (Appl. Phys. Lett., 2021, 119, 19, 192103), wherein we pointed out that the PL saturation in QDs can be used to create all-optical switches in combination with a bulk semiconductor host.

11.
Biomed Res Int ; 2022: 6336700, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909482

RESUMO

An algorithm framework based on CycleGAN and an upgraded dual-path network (DPN) is suggested to address the difficulties of uneven staining in pathological pictures and difficulty of discriminating benign from malignant cells. CycleGAN is used for color normalization in pathological pictures to tackle the problem of uneven staining. However, the resultant detection model is ineffective. By overlapping the images, the DPN uses the addition of small convolution, deconvolution, and attention mechanisms to enhance the model's ability to classify the texture features of pathological images on the BreaKHis dataset. The parameters that are taken into consideration for measuring the accuracy of the proposed model are false-positive rate, false-negative rate, recall, precision, and F1 score. Several experiments are carried out over the selected parameters, such as making comparisons between benign and malignant classification accuracy under different normalization methods, comparison of accuracy of image level and patient level using different CNN models, correlating the correctness of DPN68-A network with different deep learning models and other classification algorithms at all magnifications. The results thus obtained have proved that the proposed model DPN68-A network can effectively classify the benign and malignant breast cancer pathological images at various magnifications. The proposed model also is able to better assist the pathologists in diagnosing the patients by synthesizing the images of different magnifications in the clinical stage.


Assuntos
Neoplasias da Mama , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Atenção à Saúde , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos
12.
Curr Pediatr Rev ; 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443973

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a disorder that causes stomach pain in children and adolescents. It may also impact one's quality of life. IBS is linked to gastrointestinal issues such as diarrhoea and constipation. Despite the identification of several potential pathophysiological pathways, the aetiology of IBS remained unknown. OBJECTIVE: The aim of this paper is to discuss the diagnosis, pathogenesis, case studies and treatment of Irritable bowel syndrome in children and adolescents. METHOD: This systematic review covered relevant papers from the previous ten years that were accessible in Science Direct, Elsevier, NCBI, and Web of Science related to the pathophysiology and function of pharmacological drugs such as antidepressants, antispasmodics, prokinetics, and antibiotics in children with irritable bowel syndrome. RESULT: Only a few prospective therapy techniques have been investigated in children, and even fewer of those have been demonstrated to be effective. This article presents case studies including 50-59 children, which demonstrate a favourable acceptable impact that is more effective than a placebo in terms of reducing symptoms and improving the overall quality of life in children who have irritable bowel syndrome. Furthermore, the majority of the pathophysiological explanations and treatment options discussed are based on adult studies. These major issues arose when treating paediatric IBS, and they must be addressed in order to properly treat children with IBS. Trials that focus on many combinations of pharmacological and non-pharmacological therapies seem to be more helpful. DISCUSSION: In recent years, a number of systematic reviews have been conducted to evaluate the efficacy of medication treatments in children for IBS; however, the dependability of these systematic reviews needs to be further investigated owing to the various experimental designs and levels of evidence used. This article highlights paediatric therapy options, including pharmaceutical medications such as antidepressants, antispasmodics, prokinetics, and antibiotics. The goal is to alleviate IBS symptoms while also enhancing the quality of life for children with this illness.

13.
Materials (Basel) ; 14(7)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801574

RESUMO

We are reporting an esoteric method to determine the optical bandgap of direct gap materials by employing Urbach's rule. The latter, which describes the slope of the band tail absorption in semiconductors, in its original version, cannot be employed to pinpoint the optical bandgap. Herein, however, we show that a modified form of Urbach's rule defines the optical bandgap, and therefore, enables the accurate determination of the optical bandgap energy, which turns out to be identical with the threshold energy for the band tail absorption. The model further produces an explicit expression for the absorption coefficient at the optical bandgap energy.

14.
J Phys Chem B ; 125(29): 8185-8192, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34270252

RESUMO

Adding amines to liquid nitromethane (NM) is known to lower the threshold for the shock-to-detonation transition because amines catalyze proton transfer reactions that are the initial steps in the energy release process. We studied NM with 1 wt % ethylenediamine (NM/EDA) with 4 ns input shocks using time and space resolved diagnostics: photon Doppler velocimetry (PDV), optical pyrometry, and nanosecond video imaging. The 4 ns shocks are fast enough to time-resolve the reaction kinetics and the shock-to-detonation transition. We find that it is possible to shock ignite the NM/EDA without producing a detonation, so there is more to amine sensitization of the shock-to-detonation process than simply lowering the barrier to initial reactions. We find that although 1 wt % EDA has little effect on the ambient properties of NM, it dramatically alters the Hugoniot. The shock speed in NM/EDA is reduced, indicating that shocked NM/EDA is significantly more compressible than NM. Higher compressibility is associated with greater adiabatic heating, so EDA both lowers the barrier to proton transfer reactions and increases shock energy absorption. To explain the enhanced compressibility, we propose that shocking NM/EDA produces a reactive flow that has a much higher ionic strength than in NM. The sudden transformation from a molecular liquid to an ionic liquid with stronger intermolecular interactions is responsible for enhanced compressibility and shock heating.


Assuntos
Metano , Nitroparafinas , Etilenodiaminas , Cinética , Metano/análogos & derivados
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa