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1.
Dalton Trans ; 53(12): 5616-5623, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38439632

RESUMO

The chemokine receptor CXCR4 is implicated in multiple diseases including inflammatory disorders, cancer growth and metastasis, and HIV/AIDS. CXCR4 targeting has been evaluated in treating cancer metastasis and therapy resistance. Cyclam derivatives, most notably AMD3100 (Plerixafor™), are a common motif in small molecule CXCR4 antagonists. However, AMD3100 has not been shown to be effective in cancer treatment as an individual agent. Configurational restriction and transition metal complex formation increases receptor binding affinity and residence time. In the present study, we have synthesized novel trans-IV locked cyclam-based CXCR4 inhibitors, a previously unexploited configuration, and demonstrated their higher affinity for CXCR4 binding and CXCL12-mediated signaling inhibition compared to AMD3100. These results pave the way for even more potent CXCR4 inhibitors that may provide significant efficacy in cancer therapy.


Assuntos
Complexos de Coordenação , Ciclamos , Compostos Heterocíclicos , Benzilaminas , Complexos de Coordenação/farmacologia , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/química , Receptores CXCR4/antagonistas & inibidores
2.
Luminescence ; 37(9): 1482-1491, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35859299

RESUMO

Nacre structure has aragonite polygonal tablets, tessellated to generate separate layers, and exhibits adjacent layers and tablets within a layer bonded by a biopolymer. Here, we report the development of a nacre-like organic/inorganic hybrid nanocomposite coating consisting of epoxy tablets as well as rare-earth-activated aluminate and graphene oxide tablet/tablet interfaces. The lanthanide-activated aluminate was prepared using a high temperature solid-state approach followed by top-down technology to provide the phosphor nanoparticles (PNPs). Graphene oxide nanosheets were prepared from graphite. The prepared epoxy/graphene/phosphor nanocomposites were applied onto mild steel. Covalent bonds were formed between epoxy polymer chains resin and the graphene oxide nanosheets. These interface interactions resulted in a tough surface, high tensile strength, and excellent durability. The use of phosphor in the nanoparticle form guaranteed that no agglomerations were produced throughout the hardening procedure by allowing better distribution of PNPs in the nacre-like matrix. The generated nacre-like substrates displayed reversible fluorescence. The excitation of the white coloured nacre-like coats at 367 nm resulted in a green emission band at 518 nm as designated by the Commission Internationale de l'éclairage (CIE) Laboratory and photoluminescence spectra. Various analysis methods were utilized to inspect the surface structure and elemental composition of the nacre-like coats. An improved hydrophobicity and mechanical characteristics were detected when increasing the phosphor concentration. Due to the astonishing characteristics of the prepared nacre-like composite paint, both ceramics and metals can benefit from the current simple strategy.


Assuntos
Grafite , Elementos da Série dos Lantanídeos , Nácar , Nanocompostos , Nanopartículas , Resinas Epóxi , Grafite/química , Nácar/química , Nanocompostos/química
3.
Comput Biol Chem ; 97: 107643, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35189479

RESUMO

The current research focuses on the treatment of Cr(III), Fe(III) and Cu(II) metal ions with aryl hydrazone ligand named (E)-4-(((diphenylmethylene)hydrazono)methyl)benzene-1,3-diol (DPHB) to afford four novel solid complexes with high yields. Different characterization approaches, including infrared, UV-visible, and NMR spectroscopies, elemental analyses, and thermal gravimetric analysis (TGA), revealed that all mononuclear crystalline metal chelates with good thermal stability had a six-coordination with octahedral geometry. Density Functional Theory (DFT) computations were used and provided a reasonable explanation for these metal chelates' electrical and structural features. Furthermore, investigations of electronic absorption spectroscopy, hydrodynamics, and electrophoresis demonstrated that these new compounds interact with calf thymus deoxyribonucleic acid (CT-DNA) in a variety of ways. As a result, the Kb and ∆Gb≠ values of such interactions were in the following order: DPHBCu > DPHBCr > DPHBFe complex. Additionally, the novel metal chelates have been studied anti-bathogenically and found to be significantly effective compared to the comparable DPHB hydrazone ligand. The anti-proliferative activities of the investigated compounds were also evaluated against different lines of cancer cells and exhibited significant cytotoxic activity. In addition, observations of antioxidant activity suggest that antioxidant activity relative to ordinary ascorbic acid was demonstrated in the molecule.


Assuntos
Compostos Férricos , Hidrazonas , DNA/química , Teoria da Densidade Funcional , Hidrazonas/farmacologia , Ligantes , Testes de Sensibilidade Microbiana
4.
Saudi J Biol Sci ; 28(8): 4461-4471, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34354431

RESUMO

Fusarium species threaten wheat crops around the world and cause global losses. The global trend is toward using biological materials such as selenium (Se) in nano form to control these fungi. Bulk selenium is toxic and harmful at high doses; however, selenium nanoparticles are safe; therefore, the aim of this study to employ the biological selenium nanoparticles (BioSeNPs) synthesized by Lactobacillus acidophilus ML14 in controlling wheat crown and root rot diseases (CRDs) induced by Fusarium spp., especially Fusarium culmorum and Fusarium graminearum, and their reflection on the growth and productivity of wheat. The ability of BioSeNPs to suppress the development and propagation of F. culmorum and F. graminearum and the CRDs incidence were also investigated. The obtained BioSeNPs were spherical with a size of 46 nm and a net charge of -23.48. The BioSeNPs significantly scavenged 88 and 92% of DPPH and ABTS radicals and successfully inhibited the fungal growth in the range of 20-40 µg/mL; these biological activities were related to the small size of BioSeNPs and the phenolic content in their suspension. Under greenhouse conditions, the wheat supplemented with BioSeNPs (100 µg/mL) was significantly reduced the incidence of CRDs by 75% and considerably enhanced plant growth, grain quantity and quality by 5-40%. Also, photosynthetic pigments and gas exchange parameters were significantly increased as compared to chemical selenium nanoparticles (Che-SeNPs) and control. This study results could be recommended the use of BioSeNPs (100 µg/mL) in reducing CRDs incidence and severity in wheat plants, enhancing their tolerance with drought and heat stress, and increasing their growth and productivity as compared to control and Che-SeNPs.

5.
Saudi J Biol Sci ; 28(8): 4592-4604, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34354445

RESUMO

This work aims to evaluate the antibacterial activity of biological zinc nanoparticles (BIO-ZnONPs) against pathogenic fish bacteria and assess the effect of BIO-ZnONPs on the performance, behavior, and immune response in Nile tilapia (Oreochromis niloticus) as compared to chemical zinc nanoparticles (CH- ZnONPs). Aspergillus niger TS16 fabricated the BIO-ZnONPs were spherical shape with the average size of 45 nm and net charge of -27.23 mV. Generally, the results indicate that BIO-ZnONPs were more effective than CH- ZnONPs in enhancing the performance properties of Nile tilapia. Five experimental groups of Nile tilapia (initial body weight of 20.2 g) were treated with two concentrations of 0.5 and 1 mg L-1 from biological and chemical ZnONPs, while the fifth group was served as a control. After ten weeks of treated water with ZnONPs, the performance, feed efficiency parameters, feeding, and swimming behaviors significantly improved in BIO-ZnONPs treated groups (P < 0.05). The liver function, LYZ activity, and NBT values were significantly enhanced in the 0.5 mg L-1 BIO-ZnONPS group compared to CH- ZnONPs group and control (P < 0.05). Furthermore, the lowest cortisol and the highest testosterone and growth hormone levels were recorded in 1 mg L-1 BIO-ZnONPs group. Regarding the antibacterial effects, BIO-ZnONPs displayed the lower total bacterial loads in water and fish tissues (intestine, gills, skin, and muscle) and the maximum antibacterial properties against pathogenic bacteria (Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Aeromonas hydrophila). Our study exemplifies novel findings of BIO-ZnONPs in the promotion of fish health and production and its antibacterial properties in Nile tilapia.

6.
Molecules ; 26(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671247

RESUMO

In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, 1H- and 13C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition.


Assuntos
Anti-Infecciosos/farmacologia , Complexos de Coordenação/síntese química , DNA/metabolismo , Hidrazonas/síntese química , Hidrazonas/farmacologia , Metais/química , Micelas , Neoplasias/patologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Sobrevivência Celular/efeitos dos fármacos , Condutividade Elétrica , Células HeLa , Humanos , Hidrazonas/química , Ligantes , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química
7.
Inorg Chem Commun ; 126: 108472, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33531865

RESUMO

The salt of Aurintricarboxylic acid (ATA) was utilized in this study to synthesize new alkaline earth metal ion complexes. The analytical results proposed the isolation of mononuclear (Sr+2&Ba+2) and binuclear complexes (Mg+2&Ca+2). These complexes were analyzed by available analytical and spectral techniques. The tetrahedral geometry was suggested for all complexes (SP3) through bidentate binding mode of ligand with each central atom. UV-Vis spectra reveal the influence of L â†’ M charge transfer and the estimated optical band gap mostly appeared close to that for known semiconductors. XRD, SEM and TEM studies were executed for new complexes and reflects the nano-crystallinity and homogeneous morphology. The structural forms of ATA and its complexes were optimized by DFT/B3LYP under 6-31G and LANL2DZ basis sets. The output files (log, chk &fchk) were visualized on program screen and according to numbering scheme, many physical features were obtained. It is worthy to note that, a virtual simulation for the inhibition affinity towards COVID-19 proteins as proactive study before the actual application, was done for ATA and its complexes. This was done in addition to drugs currently applied in curing (Hydroxychloroquine & Lopinavir), for comparison and recommendation. Drug-likeness parameters were obtained to evaluate the optimal pharmacokinetics to ensure efficacy. Furthermore, simulated inhibition for COVID-19 cell-growth, was conducted by MOE-docking module. The negative allosteric binding mode represents good inhibitory behavior of ATA, Ba(II)-ATA complex and Lopinavir only. All interaction outcomes of Hydroxychloroquine drug reflect unsuitability of this drug in treating COVID-19. On the other hand, there is optimism for ATA and Lopinvir behaviors in controlling COVID-19 proliferation.

8.
Materials (Basel) ; 13(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352979

RESUMO

Fe-Pd magnetic shape-memory alloys are of major importance for microsystem applications due to their magnetically driven large reversible strains under moderate stresses. In this context, we focus on the synthesis of nanostructured Fe70Pd30 shape-memory alloy antidot array thin films with different layer thicknesses in the range from 20 nm to 80 nm, deposited onto nanostructured alumina membranes. A significant change in the magnetization process of nanostructured samples was detected by varying the layer thickness. The in-plane coercivity for the antidot array samples increased with decreasing layer thickness, whereas for non-patterned films the coercive field decreased. Anomalous coercivity dependence with temperature was detected for thinner antidot array samples, observing a critical temperature at which the in-plane coercivity behavior changed. A significant reduction in the Curie temperature for antidot samples with thinner layer thicknesses was observed. We attribute these effects to complex magnetization reversal processes and the three-dimensional magnetization profile induced by the nanoholes. These findings could be of major interest in the development of novel magnetic sensors and thermo-magnetic recording patterned media based on template-assisted deposition techniques.

9.
J Anim Physiol Anim Nutr (Berl) ; 104(6): 1851-1866, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32969538

RESUMO

In the last two decades, poultry and animal industries became increasingly interested in using plant-based feed supplements, herbs and their derivatives to retain or enhance their health and productivity. These health benefits for the host mainly attributed to the secondary plant metabolites, namely polyphenols. Polyphenols are renowned for their antioxidant, immunomodulatory, anti-mutagenic and anti-inflammatory properties. However, despite these advantages of polyphenols, they have been characterized by poor absorption in the gut and low concentration in target cells that compromise their role as effective antioxidants. The low bioavailability of polyphenols necessitates the need for further investigations to harness their full potential in poultry farms. This review is existing evidence about the bioavailability of polyphenols and their antioxidant, immunomodulatory, antimicrobial, detoxification properties and their impacts on poultry performance.


Assuntos
Ciências da Nutrição Animal , Polifenóis , Aves Domésticas , Animais , Anti-Inflamatórios , Antioxidantes , Extratos Vegetais , Polifenóis/farmacologia
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