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1.
Cell Biochem Biophys ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850406

RESUMO

Cancer, defined by the continuous, uncontrollable proliferation of cells in the human body, is a disease with a rapidly increasing incidence and mortality rate. Scientists are looking for novel ways to cure and prevent this sneaky disease because of the toxicity of contemporary chemotherapy and the cancer cells' resilience to anticancer drugs. Determining the effect of herbal medicines, which do not have as harmful side effects as synthetic drugs, on cancer cell lines is an essential preliminary study in the production of effective drugs against cancer. In this study, the phenolic acid profile, antioxidant capacity, and cytotoxicity of the medicinal plant Mespilus germanica (MG) leaf extract were determined, and its effects on the expression of some apoptotic, necrotic, and autophagic pathway genes of MCF7 (Human breast cancer line) and A549 (Human lung cancer line) and healthy HDF (Human Dermal Fibroblasts) cells were investigated for the first time. The LCMS device detected many important phenolic compounds previously reported to act against cancer cells in Mespilus germanica leaf extract. DPPH and total phenolic content showed high antioxidant capacity. The cytotoxicity of MG was determined by the MTT method. The levels of mRNA transcription for Atg5, Atg3, Ripk1, Bcl2, Bax, Apaf1, Caspase-8, Caspase-7, Caspase-3, and Caspase-9, as well as the expression patterns of the DNA damage markers P53 and Parp-1 genes, were assessed. MG leaf extract did not cause significant toxicity against healthy HDF cells. However, it had a cytotoxic effect on A549 and MCF7 cancer cell lines, increasing the transcription levels of essential genes involved in cell death mechanisms. This research is the first to analyze the phenolic components and antioxidant capabilities of leaf extracts from Mespilus germanica. Additionally, it investigates the impact of these extracts on crucial genes involved in cell death pathways of A549 lung cancer, MCF7 breast cancer, and non-cancerous HDF (Human Dermal Fibroblasts) cells.

2.
J Biomol Struct Dyn ; : 1-16, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982719

RESUMO

Two novel quinoline-anthracene conjugates comprising styrylquinoline and anthracene moieties linked by triazole bridges were designed and synthesized in good yields. These molecules were determined for some metabolic enzymes activities. Results indicated that the synthetic molecules exhibited powerful inhibitory actions against all aims as compared to the control molecules. Ki values of novel compound QA-1 for hCA I, hCA II, AChE, and α-glycosidase enzymes were obtained of 20.18 ± 2.46 µM, 14.63 ± 1.14 µM, 71.48 ± 7.76 nM, 401.35 ± 36.84 nM, respectively. Both compounds showed promising candidate complexes for drug development with considerable in vitro different enzymes inhibitory activities. The binding conformations patterns and interaction of QA-1 and QA-2 compounds with α-glucosidase, acetycholinesterase, carbonic anhydrase-I and carbonic anhydrase-II enzymes were investigated through molecular docking profiles. The docking outputs are consistent with the Ki and IC50 values of novel compounds. Three dimensional geometries and electronic properties of the title compounds were obtained by the applicational computational approach at B3LYP/6-31++G(d,p) level of theory.Communicated by Ramaswamy H. Sarma.

3.
ChemistryOpen ; 11(6): e202200033, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35642135

RESUMO

We report, for the first time, a detailed crystallographic study of the supramolecular arrangement for a set of zinc(II) Schiff base complexes containing the ligand 2,6-bis((E)-((2-(dimethylamino)ethyl)imino)methyl)-4-R-phenol], where R=methyl/tert-butyl/chloro. The supramolecular study acts as a pre-screening tool for selecting the compartmental ligand R of the Schiff base for effective binding with a targeted protein, bovine serum albumin (BSA). The most stable hexagonal arrangement of the complex [Zn-Me] (R=Me) stabilises the ligand with the highest FMO energy gap (ΔE=4.22 eV) and lowest number of conformations during binding with BSA. In contrast, formation of unstable 3D columnar vertebra for [Zn-Cl] (R=Cl) tend to activate the system with lowest FMO gap (3.75 eV) with highest spontaneity factor in molecular docking. Molecular docking analyses reported in terms of 2D LigPlot+ identified site A, a cleft of domains IB, IIIA and IIIB, as the most probable protein binding site of BSA. Arg144, Glu424, Ser428, Ile455 and Lys114 form the most probable interactions irrespective of the type of compartmental ligands R of the Schiff base whereas Arg185, Glu519, His145, Ile522 act as the differentiating residues with ΔG=-7.3 kcal mol-1 .


Assuntos
Bases de Schiff , Zinco , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Bases de Schiff/química , Bases de Schiff/metabolismo , Soroalbumina Bovina/química
4.
Turk J Chem ; 44(4): 1200-1215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488222

RESUMO

Schiff base derivatives with anthracene- and pyrene-based units, A1-A6 and P1-P6 were synthesized (89%-99% yields). Schiff base derivatives were designed to possess an heterocyclic moiety on one side to enhance the coordination ability towards metals. To investigate the biological assay of the newly synthesized compounds, their DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, metal chelating, reducing power, antibacterial and DNA binding activities were tested. A6 (63.1%) showed the maximum free radical scavenging activity among all. However, compound P3 at concentration of 200 µg/mL possessed the highest metal chelating (45.8%) activity and power of reduction. In addition, P3 and A6 showed antibacterial activity against all bacteria tested and both compounds were very well bound to CT-DNA. Density functional theory method with B3LYP/6-311++G(d,p) basis set was performed to get information about the structural and electronic properties of the present compounds. In addition, the metal coordination properties of the dimers of the parent Schiff bases were investigated through interactions with Zn2+.

5.
Phys Chem Chem Phys ; 17(38): 25572-82, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26372605

RESUMO

A novel series of donor-acceptor-donor (D-A-D) structured pyridine derivatives were synthesised and detailed photo-physical investigations were made using mainly steady-state and time-resolved spectroscopy techniques at varying temperatures. The investigations showed that the molecules have solvent polarity and temperature dependent excited-state configurations, confirmed in two different polarity solvents (295-90 K), i.e. methyl cyclohexane (MCH) and 2-methyltetrahdrofurane (2-MeTHF). In MCH, the investigations revealed dual fluorescence over the temperature range of 295-90 K. At 295 K, the ground-state configuration of the molecules has a partially twisted geometry as determined by DFT calculation, yet the emission originates totally from a locally excited (LE) state, however once the temperature is lowered to 90 K, the twisted molecular configuration is stabilised, and the emission originates from a fully-relaxed intramolecular charge transfer state (ICT), this is contrary to the systems where structural reorganisation stabilises ICT and this is frozen out at low temperatures. The DFT calculations revealed different ground state molecular configurations due to the presence of different electron-donating groups, e.g. the molecule including anthracene groups has a near 90° twisted geometry whereas the triphenylamine including molecule has a pyramidal geometrical folding, therefore, the decrease in temperature restricts the donor degree of rotational freedom. In 2-MeTHF solution, the fluorescence spectrum of both molecules is always of ICT character, but gradually red-shifts through the fluid to glass transition temperature (∼135 K), in this case, the fluorescence occurs after structural and solvent-shell relaxations, however, upon cooling below 135 K, the spectra dramatically shift back to blue giving rise to strong emission from an ICT excited-state (but not the LE state) where the molecules have unrelaxed geometries. This significant change in the nature of the emitting species was explained with specific solvent-solute dynamic interactions in the vicinity of the solvation shell and the effect of thermal excitation of molecular vibrational modes of the C-C bond linking donor and acceptor units. Finally, we confirmed that the molecules have ICT ground-state geometry in the solid-state phase (spin-coated films), and the time-resolved decay dynamics were investigated comparing the spin-coated films (at RT and 25 K) and MCH solutions (at 295 K and 90 K).

6.
J Environ Biol ; 31(1-2): 213-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20648835

RESUMO

This investigation evaluates two primary forest transportation systems, consecutive skyline yarding system integrated with two different types of skyline yarding systems and the gravity skidding system, considering technical, economical and environmental aspects. The results indicated that the productivity of consecutive skyline yarding system was 4.97 m3 hr(-1), while the productivity of the gravity skidding system was 0.74 m3 hr(-1). The unit costs of these primary transportation systems were found to be $5.98 and $51.28 m3, respectively. Besides, the gravity skidding system caused more damages on skidded logs, residual trees, and forest soil than that of consecutive skyline yarding system. It was also indicated that two different skyline yarding systems produced definite and different average yarding distances and technical capacities, which negatively affected the overall performance of the consecutive skyline yarding system. Therefore, different types of skyline yarding systems should not be integrated into the consecutive yarding systems.


Assuntos
Agricultura Florestal/métodos , Árvores/fisiologia , Animais , Ecossistema , Meios de Transporte
7.
J Hazard Mater ; 167(1-3): 440-8, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19195778

RESUMO

In this study, all possible mono-, di- and tri-nitro-substituted triazine compounds have been considered as potential candidates for high-energy density materials (HEDMs) by using quantum chemical treatment. Geometric and electronic structures, thermodynamic properties and detonation performances of these nitro-substituted triazines have been systematically studied using density functional theory (DFT, B3LYP) at the level of 6-31G(d,p), 6-31+G(d,p), 6-311G(d,p), 6-311+G(d,p) and cc-pVDZ basis sets. Moreover, thermal stabilities have been evaluated from the homolytic bond dissociation energies (BDEs). Detailed molecular orbital (MO) investigation has been performed on these potential HEDMs. According to the results of the calculations, mono-, di- and tri-nitro-substituted derivatives of symmetric 1,3,5-triazine have been found to be more stable than their 1,2,3 and 1,2,4 counterparts.


Assuntos
Substâncias Explosivas/química , Modelos Moleculares , Nitrocompostos/química , Triazinas/química , Teoria Quântica , Termodinâmica
8.
J Hazard Mater ; 163(1): 285-94, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18657904

RESUMO

In the present work, the structural and electronic properties of vomitoxin (deoxynivalenol, a mycotoxin) and all of its possible tautomers have been investigated by the application of B3LYP/6-31G(d,p) type quantum chemical calculations. According to the results of the calculations, tautomer V(4) has been found to be the most stable one among all the structures both in the gas and aqueous phases. The calculations also indicated that, vomitoxin and V(2) possess the deepest and the highest lying HOMO levels, respectively. Hence, V(2) is to be more susceptible to oxidations than the others. On the other hand, V(5)(S) and vomitoxin have the lowest and the next lowest LUMO energies, respectively. Whereas, V(1) and V(2) possess quite highly lying (within the group) LUMO energy levels which result in comparatively unfavorable reduction potentials. Some important geometrical and physicochemical properties and the calculated IR spectra of the systems have also been reported in the study.


Assuntos
Modelos Químicos , Tricotecenos/química , Isomerismo , Modelos Moleculares , Estrutura Molecular , Espectrofotometria Infravermelho
9.
J Hazard Mater ; 153(1-2): 329-39, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17904283

RESUMO

Nivalenol, a highly poisonous mycotoxin, and its possible tautomers have been considered theoretically by RHF/6-31G/d,p) and B3LYP/6-31G(d,p) calculations together with a semi-empirical PM3 method. The calculations revealed that some of the tautomers are more stable and exothermic than nivalenol. The calculated IR spectra as well as some geometrical and physicochemical properties of the structures considered have been presented.


Assuntos
Poluentes Ambientais/química , Micotoxinas/química , Tricotecenos/química , Isomerismo , Modelos Químicos
10.
Environ Monit Assess ; 142(1-3): 109-16, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17874200

RESUMO

Forest management today has to meet a number of objectives. Planning of multi-functional forest road networks is one essential for meeting the aims of the sustainable forest concept. Road construction damages the natural environment unless it is carefully thought out. As forest engineers we have to consider the protection of nature when designing forest roads. With this aim in mind, a new network planning approach was developed for wood-harvesting. A geographical information system (GIS) was used to evaluate the data and planning process. The new forest road network plan for Catak Forest District constituted the addition of a new 16-road segment, total length 59.067 km, to the existing road network plan, for the purpose of wood-harvesting operations. Forest road density value was determined as 22.8 m/ha: the opening-up rate of the area was increased to 77.8% and the opening-up rate of the existing stand value was increased to 94.3% after close examination. 90.2% of roads were planned for the forest areas where there is likely to be minimal negative environmental impact.


Assuntos
Conservação dos Recursos Naturais/métodos , Meios de Transporte , Árvores , Bases de Dados Factuais , Ecossistema , Monitoramento Ambiental , Arquitetura de Instituições de Saúde , Agricultura Florestal , Mapas como Assunto , Veículos Automotores , Formulação de Políticas , Turquia
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