Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Heliyon ; 10(3): e25438, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322891

RESUMO

This study investigates the potential of utilizing Aloe vera-assisted green synthesis with transition metal dopants of Ag and Cu for greater efficiency and sustainability in advanced scientific applications utilizing ZnO nanoparticles. Samples were prepared using the co-precipitation method, maintaining a basic pH media of 10. Aloe vera gel extract was chosen for its acclaimed role as a stabilizing and reducing agent and its proven antioxidant, antibacterial, and anticancer properties. The XRD report revealed the hexagonal Wurtzite crystal structure of nanoparticles, exhibiting a crystallite size range of 17-23 nm with substantial alterations in lattice parameters, dislocation density, and bond lengths when dopants were added. Additionally, EDX analysis confirmed the perfect doping of Ag and Cu in ZnO without any impurities. SEM analysis indicated a reduction in agglomeration, accompanied by a transition in particle morphology from columnar to globular. Additionally, the optical study showed a band gap range of 3.18-3.27 eV, confirming it to be a wide band gap semiconductor. The effect of dopants resulted in an increase in transparency and band gap, while a decrease in absorption coefficient in the visible wavelength region. With increasing temperature, a decline in electrical resistivity was noted, with co-doped nanoparticles consistently exhibiting the lowest resistivity, affirming semiconductor characteristics. Most importantly, A remarkable antibacterial efficacy was noticed at low concentrations against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The zone of inhibition produced by nanoparticles exhibited values akin to the antibiotic control, even at substantially lower doses. This research offers a comprehensive analysis of the effects of Ag and Cu in Aloe vera-assisted green-synthesized ZnO nanoparticles, concurrently addressing their potential applications in biomedical, energy storage, and optoelectronic devices.

2.
Appl Organomet Chem ; 35(1): e6067, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33173252

RESUMO

Symmetrical bis-Schiff bases (LH 2) have been synthesized by the condensation of 1,6-hexanediamine (hn) and carbonyl or dicarbonyl. One of the synthesized Schiff bases has been subjected to the molecular docking for the prediction of their potentiality against coronavirus (SARS-CoV-2). Molecular docking revealed that tested Schiff base possessed high binding affinity with the receptor protein of SARS CoV-2 compared with hydroxychloroquine (HCQ). The ADMET analysis showed that ligand is non-carcinogenic and less toxic than standard HCQ. Schiff bases acting as dibasic tetra-dentate ligands formed titanium (IV) complexes of the type [TiL(H2O)2Cl2] or [TiL(H2O)2]Cl2 being coordinated through ONNO donor atoms. Ligands and complexes were characterized by the elemental analysis and physicochemical and spectroscopic data including FTIR, 1H NMR, mass spectra, UV-Visible spectra, molar conductance, and magnetic measurement. Optimized structures obtained from quantum chemical calculations supported the formation of complexes. Antibacterial, antifungal, and anti-oxidant activity assessments have been studied for synthesized ligands and complexes.

3.
Food Chem ; 239: 502-510, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28873597

RESUMO

A novel antioxidant peptide YD1 (∼1.0kDa), purified from the strain Bacillus amyloliquefaciens CBSYD1, displayed activity in several in vitro assays and was also efficient against Gram-positive, Gram-negative as well as multidrug-resistant (MDR) bacteria. Strain growth was adapted to bile-salt conditions where a clear halos-zone was observed in a bile-salt plate assay and was viable in different digestive track conditions. YD1 treatment on RAW 264.7 cells increased the transcriptional and translational activities of NF-E2-related factor-2 (Nrf-2) through the enhanced levels of heme oxygenase-1 (HO-1). Furthermore, the YD1-treated group showed higher levels of antioxidant enzymes compared to the oxidative stress group. YD1 demonstrated a strong antioxidant activity by decreasing nitric oxide (NO) and reactive oxygen species (ROS) in RAW 264.7 cells. This study suggests that YD1 and the strain could be a natural antioxidant and a probiotic candidate respectively.


Assuntos
Bacillus amyloliquefaciens , Antioxidantes , Heme Oxigenase-1 , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Peptídeos , Espécies Reativas de Oxigênio
5.
Inflammation ; 40(2): 688-696, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28214973

RESUMO

The purified BCP61 was reported to be a unique low-molecular-weight (MW) anti-microbial peptide because of its non-identical alanine-rich N-terminal sequence. In this study, we investigated the anti-inflammatory effects of BCP61 on induction of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), pro-inflammatory cytokines, nuclear factor-kappa B (NF-κB), and mitogen-activated protein kinases (MAPKs) in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. The treatment with BCP61, with varying concentrations of 10, 50, and 100 µg/mL, inhibited levels of expression of LPS-induced NF-κB and MAPKs (extracellular signal-related kinases (ERKs), c-Jun NH2-terminal kinase (JNK), and mitogen-activated protein (p38)) as well as production of pro-inflammatory mediators, such as nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). The results suggested that BCP61 prevents inhibitor of kappa B (IκBα) phosphorylation and degradation, thereby inhibiting the nuclear translocation of the p65 protein. We do report that the use of BCP61 in the treatment of inflammation as well as microbial infection could be a potent therapeutic candidate.


Assuntos
Anti-Inflamatórios/farmacologia , Proteínas de Bactérias/farmacocinética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator de Transcrição RelA/antagonistas & inibidores , Alanina , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/uso terapêutico , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Proteínas I-kappa B/metabolismo , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Camundongos , Peptídeos , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo
6.
Int J STD AIDS ; 25(2): 138-44, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23970638

RESUMO

To evaluate a leucocyte esterase test as a predictor of gonorrhoea or chlamydia in asymptomatic Aboriginal males at the Central Australian Aboriginal Congress Male Clinic (Ingkintja), first-void urine samples and clinical information were collected from consecutive asymptomatic males presenting to the Ingkintja in Alice Springs between March 2008 and December 2009. Urine was tested immediately with a leucocyte esterase test dipstick and then by polymerase chain reaction for gonorrhoea and chlamydia. Among the 292 specimens from asymptomatic males, 15.4% were positive for gonorrhoea or chlamydia. In this group, compared with polymerase chain reaction result for gonorrhoea or chlamydia, leucocyte esterase test alone and in combination with age ≤35 years showed sensitivities of 66.7% and 60%, specificities of 90.7% and 94.7%, positive predictive values of 56.6% and 67.5%, negative predictive values of 93.7% and 92.8% and the area under receiver operating characteristics curve values of 0.79 and 0.85, respectively. Leucocyte esterase tests can reasonably be used as a basis for immediate empirical treatment for gonorrhoea or chlamydia in asymptomatic central Australian Aboriginal men under 35 years of age.


Assuntos
Hidrolases de Éster Carboxílico/urina , Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Gonorreia/diagnóstico , Neisseria gonorrhoeae/isolamento & purificação , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Infecções por Chlamydia/etnologia , Infecções por Chlamydia/urina , Gonorreia/urina , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Atenção Primária à Saúde , Fitas Reagentes , Serviços de Saúde Rural , Sensibilidade e Especificidade , Fatores Socioeconômicos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA