Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; 239: 124243, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37011746

RESUMO

In chronic liver diseases, liver fibrosis occurs due to excessive extracellular matrix (ECM) protein accumulation. Approximately 2 million deaths occur yearly due to liver disease, while cirrhosis is the 11th most common cause of death. Therefore, newer compounds or biomolecules must be synthesized to treat chronic liver diseases. In this aspect, the present study focuses on the assessment of the anti-inflammatory and antioxidant impact of Bacterial Protease (BP) produced by a new mutant strain of bacteria (Bacillus cereus S6-3/UM90) and 4,4'-(2,5-dimethoxy-1,4-phenylene) bis (1-(3-ethoxy phenyl)-1H-1,2,3-triazole) (DPET) in the treatment of early stage of liver fibrosis induced by thioacetamide (TAA). Sixty male rats were divided into six groups, ten rats each as follows: (1) Control group, (2) BP group, (3) TAA group, (4) TAA-Silymarin (S) group, (5) TAA-BP group, and (6) TAA-DPET group. Liver fibrosis significantly elevated liver function ALT, AST, and ALP, as well as anti-inflammatory interleukin 6 (IL-6) and VEGF. The oxidative stress parameters (MDA, SOD, and NO) were significantly increased with a marked reduction in GSH. Expression of MAPK and MCP-1 was unregulated in the TAA group, with downregulation of Nrf2 was observed. TAA caused histopathological alterations associated with hepatic vacuolation and fibrosis, increasing collagen fibers and high immuno-expression of VEGF. On the other hand, treatment with BP successfully improved the severe effects of TAA on the liver and restored histological architecture. Our study concluded the protective potentials of BP for attenuating liver fibrosis and could be used as adjuvant therapy for treating hepatic fibrosis.


Assuntos
Células Estreladas do Fígado , Tioacetamida , Masculino , Ratos , Animais , Tioacetamida/toxicidade , Peptídeo Hidrolases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fígado , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Fibrose , Estresse Oxidativo , Endopeptidases/metabolismo , Anti-Inflamatórios/farmacologia
2.
Molecules ; 25(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059480

RESUMO

Bacterial resistance remains a significant threat and a leading cause of death worldwide, despite massive attempts to control infections. In an effort to develop biologically active antibacterial and antifungal agents, six novel aryl-substituted-1,2,3-triazoles linked to carbohydrate units were synthesized through the Cu(I)-catalyzed azide-alkyne cycloaddition CuAAC of substituted-arylazides with a selection of alkyne-functionalized sugars. The chemical structures of the new derivatives were verified using different spectroscopic techniques. The novel clicked 1,2,3-triazoles were evaluated for in vitro antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, and the obtained results were compared with the activity of the reference antibiotic "Ampicillin". Likewise, in vitro antifungal activity of the new 1,2,3-triazoles was investigated against Candida albicans and Aspergillus niger using "Nystatin" as a reference drug. The results of the biological evaluation pointed out that Staphylococcus aureus was more susceptible to all of the tested compounds than other examined microbes. In addition, some tested compounds exhibited promising antifungal activity.


Assuntos
Anti-Infecciosos/farmacologia , Química Click , Glicosídeos/farmacologia , Triazóis/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/patogenicidade , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Glicosídeos/síntese química , Glicosídeos/química , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química
3.
Environ Sci Pollut Res Int ; 24(28): 22284-22293, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28799143

RESUMO

In this work, the adsorption of chemical oxygen demand (COD) and biological oxygen demand (BOD) from treated sewage with low-cost activated carbon prepared from date palm shell waste by chemical activation method was studied. Different parameters affecting the adsorption process such as carbon dose, pH, contact time, agitation rate, and temperature were studied. Adsorption equilibrium was attained after 150 min at pH 6.0 with agitation rate of 400 rpm at 25 °C. The results showed that COD removal percentage of 95.4 and 92.8% for BOD was obtained with carbon dosage of 0.1 g/100 ml of solution. The experimental batch equilibrium results follow linear, Langmuir, and Freundlich isotherm models. The experimental data was fitted to a pseudo-second-order kinetics model controlled by pore diffusion. Thermodynamic parameter values of ΔH 0, ΔG 0, and ΔS 0 were calculated. The obtained data indicated that the adsorption was spontaneous, endothermic nature and reflects an increased randomness and degree of disorderliness at the activated carbon/sewage interface during the adsorption process investigated in this study. Concentrations of different impurities were reduced to very small value by investigated adsorption process.


Assuntos
Carvão Vegetal/química , Modelos Teóricos , Phoeniceae/química , Esgotos/química , Resíduos Sólidos , Poluentes Químicos da Água/análise , Adsorção , Análise da Demanda Biológica de Oxigênio , Difusão , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica
4.
Artigo em Inglês | MEDLINE | ID: mdl-28713784

RESUMO

Influenza A virus is a negative RNA stranded virus of the family Orthomyxoviridae, and represents a major public health threat, compounding existing disease conditions. Influenza A virus replicates rapidly within its host and the segmented nature of its genome facilitates re-assortment, whereby whole genes are exchanged between influenza virus subtypes during replication. Antiviral medications are important pharmacological tools in influenza virus prophylaxis and therapy. However, the use of currently available antiviral is impeded by sometimes high levels of resistance in circulating virus strains. Here, we identified novel anti-influenza compounds through screening of chemical compounds synthesized de novo on human lung epithelial cells. Computational and experimental screening of extensive and water soluble compounds identified novel influenza virus inhibitors that can reduce influenza virus infection without detectable toxic effects on host cells. Interestingly, the indicated active compounds inhibit viral replication most likely via interaction with cell receptors and disturb influenza virus entry into host cells. Collectively, screening of new synthesis chemical compounds on influenza A virus replication provides a novel and efficacious anti-influenza compounds that can inhibit viral replication via disturbing virus entry and indicates that these compounds are attractive candidates for evaluation as potential anti-influenza drugs.


Assuntos
Antivirais/antagonistas & inibidores , Vírus da Influenza A/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Internalização do Vírus/efeitos dos fármacos , Células A549 , Animais , Antivirais/síntese química , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Células Epiteliais/virologia , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/tratamento farmacológico , Pulmão/virologia , Simulação de Acoplamento Molecular , Infecções por Orthomyxoviridae/virologia , Replicação Viral
5.
Chemistry ; 18(19): 5837-42, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22461207

RESUMO

Folded dendrimers with peripheral ether side chains show a thermally induced hierarchical aggregation process, in which the transition temperature and the dimensions of the aggregates can readily be tuned via the generation number (see figure).

6.
Nanoscale ; 4(2): 467-72, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-22139437

RESUMO

Efficient Cu-catalyzed 1,3-dipolar cycloaddition reactions have been used to prepare two series of three regioisomers of G-1 and G-2 poly(triazole-pyridine) dendrons. The G-1 and G-2 dendrons consist of branched yet conformationally pre-organized 2,6-bis(phenyl/pyridyl-1,2,3-triazol-4-yl)pyridine (BPTP) monomeric and trimeric cores, respectively, carrying one focal and either two or four peripheral alkyl side chains. In the solid state, the conformation and supramolecular organization were studied by means of a single crystal X-ray structure analysis of one derivative. At the liquid-solid interface, the self-assembly behavior was investigated by scanning tunneling microscopy (STM) on graphite surfaces. Based on the observed supramolecular organization, it appears that the subtle balance between conformational preferences inherent in the dendritic backbone on the one side and the adsorption and packing of the alkyl side chains on the graphite substrate on the other side dictate the overall structure formation in 2D.


Assuntos
Cristalização/métodos , Dendrímeros/síntese química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Pós , Soluções , Propriedades de Superfície
7.
Chem Commun (Camb) ; 47(38): 10578-80, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21869953

RESUMO

First generation poly(triazole-phenylene) dendrimers equipped with peripheral alkyl or carboxylic acid groups to engage in van der Waals and hydrogen-bonding interactions, respectively, assemble into distinct two-dimensional nano-structures at the solid-liquid interface as revealed by high resolution STM investigations.


Assuntos
Dendrímeros/química , Química Click , Grafite/química , Ligação de Hidrogênio , Microscopia Eletrônica de Transmissão e Varredura , Nanoestruturas/química , Polímeros/química , Triazóis/química
8.
Chemistry ; 17(5): 1473-84, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21268150

RESUMO

Noncovalent interactions, especially hydrogen-bonding interactions as well as electrostatic forces, confined within one macromolecule are the key to designing foldamers that adopt well-defined conformations in solution. In the context of significant recent activities in the area of triazole-connected foldamers, so-called clickamers, we present a fundamental study that compares various model compounds that bear adjacent N-, O-, or F-heteroatom substituents. The interplay of attractive and repulsive interactions leads to rotational constraints around the single bonds attached to both the 1- and 4-positions of the 1,2,3-triazole moiety and should therefore be able to induce well-defined conformational preferences in higher oligomers and polymers, that is, foldamers. Various compounds were synthesized and characterized with regard to their preferred conformations in all three aggregation states--that is, in the gas phase, in solution as well as in the solid state--by employing DFT calculations, NMR spectroscopic experiments, and X-ray crystallography, respectively. On the basis of the thus-obtained general understanding of the conformational behavior of the individual connection motifs, heterostructures were prepared from different motifs without affecting their distinct folding characteristics. Therefore, this work provides a kind of foldamer construction kit, which should enable the design of various clickamers with specific shape and incorporated functionality.

9.
Chemistry ; 15(19): 4788-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19322772

RESUMO

Dynamic surfaces: The conformational transition of 2,6-bis(1-aryl-1,2,3-triazol-4-yl)pyridine (BTP) derivatives, triggered by a change in pH, has been observed with a sub-nm resolution by STM at the solid-liquid interface. Upon addition of trifluoroacetic acid two different BTP molecules, each forming a highly ordered physisorbed monolayer, underwent significant conformational changes from their "rosette" to their "tetragon" forms, as reflected in dramatically altered 2D self-assembly over large areas extending over hundreds of nanometers (see graphic).

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...