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1.
Microb Pathog ; 181: 106184, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37286112

RESUMO

Copper oxide nanoparticles are modern kinds of antimicrobials, which may get a lot of interest in the clinical application. This study aimed to detect the anti-capsular activity of CuO nanoparticles against Acinetobacter baumannii produce efflux pump. Thirty-four different clinical A. baumannii isolates were collected and identified by the phenotypic and genetic methods by the recA gene as housekeeping. Antibiotic sensitivity and biofilm-forming ability, capsular formation were carried out. The effect of CuO nanoparticles on capsular isolates was detected, the synergistic effects of a combination CuO nanoparticles and gentamicin against A. baumannii were determined by micro broth checkerboard method, and the effect of CuO nanoparticles on the expression of ptk, espA and mexX genes was analyzed. Results demonstrated that CuO nanoparticles with gentamicin revealed a synergistic effect. Gene expression results show reducing the expression of these capsular genes by CuO nanoparticles is major conduct over reducing A. baumannii capsular action. Furthermore, results proved that there was a relationship between the capsule-forming ability and the absence of biofilm-forming ability. As bacterial isolates which were negative biofilm formation were positive in capsule formation and vice versa. In conclusion, CuO nanoparticles have the potential to be used as an anti-capsular agent against A. baumannii, and their combination with gentamicin can enhance their antimicrobial effect. The study also suggests that the absence of biofilm formation may be associated with the presence of capsule formation in A. baumannii. These findings provide a basis for further research on the use of CuO nanoparticles as a novel antimicrobial agent against A. baumannii and other bacterial pathogens, also to investigate the potential of CuO nanoparticles to inhibit the production of efflux pumps in A. baumannii, which are a major mechanism of antibiotic resistance.


Assuntos
Acinetobacter baumannii , Nanopartículas , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Gentamicinas/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética , Proteínas de Bactérias/metabolismo
2.
Mol Biol Rep ; 50(7): 5969-5976, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37269387

RESUMO

BACKGROUND AND AIM: Binary copper-cobalt oxide nanoparticles (CuO\CoO NPs) are modern kinds of antimicrobials, which may get a lot of interest in clinical application. This study aimed to detect the effect of the binary CuO\CoO NPs on the expression of papC and fimH genes in multidrug-resistant (MDR) isolates of Klebsiella oxytoca to reduce medication time and improve outcomes. METHODS: Ten isolates of K. oxytoca were collected and identified by different conventional tests besides PCR. Antibiotic sensitivity and biofilm-forming ability were carried out. The harboring of papC and fimH genes was also detected. The effect of binary CuO\CoO nanoparticles on the expression of papC and fimH genes was investigated. RESULTS: Bacterial resistance against cefotaxime and gentamicin was the highest (100%), while the lowest percentage of resistance was to amikacin (30%). Nine of the ten bacterial isolates had the ability to form a biofilm with different capacities. MIC for binary CuO\CoO NPs was 2.5 µg/mL. Gene expression of papC and fimH was 8.5- and 9-fold lower using the NPs. CONCLUSION: Binary CuO\CoO NPs have a potential therapeutic effect against infections triggered by MDR K. oxytoca strains due to the NPs-related downregulation ability on the virulence genes of K. oxytoca.


Assuntos
Klebsiella oxytoca , Nanopartículas , Klebsiella oxytoca/genética , Antibacterianos/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
3.
J Mol Model ; 29(5): 129, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37016077

RESUMO

CONTEXT: By utilizing first-principles calculations, we studied the electronic properties of graphdiyne nanosheet (GDY) and its Si-doped counterpart, Si-GDY. Both GDY and Si-GDY sheet surfaces were examined for the drug cisplatin (CP) adsorption using adsorption energy, charge transfer, and changes in electrical conductivity as indicators. Pure GDY has little affinity for CP, according to this study. Only 7.83% of the GDY surface's bandwidth energy changed after CP adsorption. CP on Si-GDY has a gaseous energy value of -18.75 kcal/mol and an aqueous energy value of - 49.39 kcal/mol. METHODS: The prescribed medications' water-phase solubility is determined by their solvation energy value. These charges are transferred between CP and the Si-GDY sheet, which is extremely positively charged, and this gives CP the necessary binding energy. After CP adsorption, electrical conductivity of Si-GDY increased by approximately 19.01%.


Assuntos
Cisplatino , Eletrônica , Adsorção , Condutividade Elétrica
4.
J Mol Model ; 29(5): 162, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118157

RESUMO

CONTEXT: The inhibitory effect of asparagine (Asn) and its derivatives on iron (Fe) corrosion was studied by performing density functional theory (DFT) calculations. In this paper, the global and local reactivity descriptors of Asn in the protonated and neutral forms were evaluated. Also, the changes in reactivity were investigated when dipeptides were combined with Asn. Due to the increase in the reaction centers within their molecular structure, there was an enhancement in the inhibitory effect of these dipeptides. Moreover, the adsorption energies (Eads) and the adsorption configurations of Asn and small peptides (SPs) with most stability were determined on the surface of Fe(111). It was found that dipeptides had a chemical adsorption on these substrates. In the protonated forms, there was an enhancement in the absolute values of Eads between the inhibitors and the Fe(111) surfaces. Peptides were more likely to be adsorbed on the Fe surfaces, showing the great inhibitory effect of these moieties. The results of the current research demonstrate the possibility of utilizing SPs as efficient "green" corrosion inhibitors. METHODS: DFT computations were undertaken by employing the BIOVIA Material Studio with B3LYP-D3 functional and 6-31 + G* basis set. The theoretical evaluation of the inhibitory effect of asparagine (Asn) dipeptides, and the potential analysis of small peptides to protect against the corrosion of Fe, was done.


Assuntos
Aminoácidos , Dipeptídeos , Dipeptídeos/química , Asparagina/química , Adsorção , Peptídeos
5.
J Mol Model ; 29(5): 139, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37055601

RESUMO

CONTEXT: In recent years, undivided attention has been given to the unique properties of layered nitrogenated holey graphene (C2N) monolayers (C2NMLs), which have widespread applications (e.g., in catalysis and metal-ion batteries). Nevertheless, the scarcity and impurity of C2NMLs in experiments and the ineffective technique of adsorbing a single atom on the surface of C2NMLs have significantly limited their investigation and thus their development. Within this research study, we proposed a novel model, i.e., atom pair adsorption, to inspect the potential use of a C2NML anode material for KIBs through first-principles (DFT) computations. The maximum theoretical capacity of K ions reached 2397 mA h g-1, which was greater in contrast with that of graphite. The results of Bader charge analysis and charge density difference revealed the creation of channels between K atoms and the C2NML for electron transport, which increased the interactions between them. The fast process of charge and discharge in the battery was due to the metallicity of the complex of C2NML/K ions and because the diffusion barrier of K ions on the C2NML was low. Moreover, the C2NML has the advantages of great cycling stability and low open-circuit voltage (approximately 0.423 V). The current work can provide useful insights into the design of energy storage materials with high efficiency. METHODS: In this research, we used B3LYP-D3 functional and 6-31 + G* basis with GAMESS program to calculate adsorption energy, open-circuit voltage, and maximum theoretical capacity of K ions on the C2NML.

6.
RSC Adv ; 13(4): 2487-2500, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36741187

RESUMO

Lung cancer is nowadays among the most prevalent diseases worldwide and features the highest mortality rate among various cancers, indicating that early diagnosis of the disease is of paramount importance. Given that the conventional methods of cancer detection are expensive and time-consuming, special attention has been paid to the provision of less expensive and faster techniques. In recent years, the dramatic advances in nanotechnology and the development of various nanomaterials have led to activities in this context. Recent studies indicate that the graphene oxide (GO) nanomaterial has high potential in the design of nano biosensors for lung cancer detection owing to its unique properties. In the current article, a nano biosensor based on a DNA-GO nanohybrid is introduced to detect deletion mutations causing lung cancer. In this method, mutations were detected using a FAM-labeled DNA probe with fluorescence spectrometry. GO was synthesized according to Hummers' method and examined and confirmed using Fourier Transform Infrared (FT-IR) Spectrometry and UV-vis spectrometry methods and Transmission Electron Microscopy (TEM) images.

7.
Appl Biochem Biotechnol ; 195(7): 4164-4176, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36656537

RESUMO

Because nanomaterials are highly reactive and electronically sensitive towards a variety of drug molecules, they are thought of as efficient drug sensors. In the present research study, an aluminum carbide (C3Al) monolayer is employed and its interaction is examined with cyclophosphamide (CP) by performing DFT computations. The C3Al monolayer is highly reactive and sensitive towards CP according to the computations. CP interacts with the C3Al monolayer with the adsorption energy of -31.39 kcal/mol. A considerable charge transfer (CT) indicates an enhancement in the conductivity. Also, the charge density is explained based on the electron density differences (EDD). The decrease in CP/C3Al energy gap (Eg) by approximately 52.91% is due to the remarkable effect of adsorption on the LUMO and the HOMO levels. Therefore, due to the decrease in Eg which can generate an electrical signal, the electrical conductivity is considerably increased. These results suggest that the C3Al monolayer can be employed as a proper electronic drug sensor for CP. Also, the recovery time for the desorption process of CP form the surface of C3Al is 351 s at 598 K.


Assuntos
Eletricidade , Adsorção , Ciclofosfamida , Condutividade Elétrica
8.
J Mol Model ; 29(1): 27, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585505

RESUMO

Since the human body is one of the highly aggressive environments, the materials utilized for an implant should have high resistance to degradation and corrosion. One of the commonly used biomaterials in medicine is copper (Cu). The Cu corrosion can result in the release of ions in the body with high toxicity, thereby causing inflammatory diseases. Based on the literature, as biomolecules, amino acids act as a corrosion inhibitor in aggressive solutions. The current work aims at scrutinizing the inhibition impact of L-arginine (L-Arg) and L-Valine (L-Val), which have been rarely investigated, upon the corrosion process of Cu. We undertook density functional theory computations to scrutinize the inhibitory impact of L-Arg and L-Val as well as their conformers upon Cu corrosion. Also, we scrutinized the computed parameters according to the back donation of electrons between Cu and the inhibitors, transported electron fraction, energy gap, softness, hardness, EHOMO, and ELUMO. According to the theoretical indices of L-Arg, it prefers adsorption. We examined the inhibitory efficiency of L-Arg against corrosion and found that it is a promising inhibitor.


Assuntos
Materiais Biocompatíveis , Cobre , Humanos , Cobre/química , Corrosão , Materiais Biocompatíveis/química , Aminoácidos , Adsorção
9.
J Mol Model ; 28(11): 357, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36222931

RESUMO

Within this work, we scrutinized the use of BeO nanotube (BeONT) as a nanocarrier for the anticancer drug hydroxyurea (HU) through density functional theory (DFT) calculations. We utilized the functional ꞷB97XD and the basis set 6-31G**. Based on a detailed surface analysis, HU was adsorbed on the surface of the nanotube through 4 different orientations. Also, no vibrational spectra exhibited imaginary frequencies, showing the minimum energy of the relaxed structures. The maximum adsorption energy and the minimum adsorption energy are in strong physical adsorption. The BeONT exhibited p-type semiconducting characteristics in all orientations since it received electronic charge from HU. The results demonstrate the possibility of using the BeONT as a promising carrier for HU drugs.


Assuntos
Antineoplásicos , Nanotubos , Antineoplásicos/química , Berílio , Hidroxiureia/química , Modelos Moleculares , Nanotubos/química
10.
J Oleo Sci ; 71(10): 1551-1561, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36184463

RESUMO

Sorbitol accumulation in the tissue is known to cause diabetic complications. Nanotechnology-enabled biosensor methods have high sensitivity, selectivity, and more rapid detection of an analytic for sorbitol which is used as a biomarker of diabetic complications. The biosensor used aldose reductase from serum blood to oxidize the NADPH by the enzymatic reaction and reduce glucose to sorbitol. Biosensors can be developed for diagnostic testing. Developing a simple, sensitive, and rapid method for sorbitol detection is significant for efficient monitoring of diabetic complications like neuropathy at the initial stages. This project synthesized quantum dots of copper sulfide (CuS QDs) to fabricate an Electrochemical sensor for the detection of sorbitol by the UV-irradiation technique. The crystal structure of CuS QDs was characterized using X-ray diffraction (XRD), which confirmed the synthesized sample's hexagonal shape. The structure of the manufactured product was examined using energy-dispersive X-ray spectroscopy (EDX), and the result revealed just copper (Cu) and sulfide (S) elements, indicating that the synthetic material was pure. The morphology, optical properties, and particle size were investigated by scanning electron microscope (SEM), photoluminescence spectroscopy (PL), and transmission electron spectroscopy (TEM), respectively. The particle sizes of the CuS QDs were found to range between 5.4 to 9.1 nm. The CuS QDs will be dedicated to the conventional methods to synthesize the modified electrode functionalized with NADPH and covered with CuS QD (Ti-TiO2/CuS/NADPH) demonstrated switchable interfacial properties. The electrochemical process was characterized by cyclic voltammetry (CV). The developed sensor was successfully tested to detect sorbitol in human serum samples. The high catalytic activity and the redox behavior of CuS QD make it an efficient matrix for the realization of sorbitol. These results indicate that CuS QD is a suitable candidate material for developing enzyme-based sorbitol biosensors.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Aldeído Redutase , Técnicas Biossensoriais/métodos , Cobre/química , Técnicas Eletroquímicas , Eletrodos , Glucose , Humanos , NADP , Sorbitol , Sulfetos/química , Titânio
11.
Arch Microbiol ; 204(1): 51, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34935077

RESUMO

Despite the studies worldwide, the prevalence of ESßL E. coli in the Iraq is still unknown. Realization of the demographic characterization of ESßL E. coli infections will assist the prevention efforts. This study aimed to isolate clinical E. coli, determine their antimicrobial susceptibility, phenotypic and genotypic detection of ESßL-producing ability, detection of some virulence-related genes, estimate the impact of graphene nano-sheets as antibacterial, and study the adherence-related gene expressions in E. coli isolates. Graphene nano-sheets were synthesized and characterized using XRD, UV, TEM, and SEM. E. coli isolates were identified using 16S rRNA. Antibiotic resistance was detected, virulence genes (blaTEM, blaSHV, BlaCTX-M-15, papC, and fimH) were screened using PCR. The antibacterial activity of graphene nano-sheets was screened using well-diffusion assay and MIC. The gene expression of adherence genes after treatment with graphene nano-sheets was evaluated using QRT-PCR. From a total of 512 identified using 16S rRNA, 359 (69.9%) were ESßL-producing E. coli. The ESßL genotypes positive were 83.56% (300/359) of E. coli isolates with the frequencies: 85% for blaCTX-M gene, 26% for blaSHV gene, and 28% for blaTEM gene. Graphene nano-sheets showed effective antibacterial activity with MIC 25 µg/ml. Furthermore, graphene nano-sheets reduced the expression of papC, and fimH genes. This study has helped us to better understand the characteristics of ESßL E. coli, their adherence gene harboring, and the potential ability of graphene nano-sheets to reduce bacterial growth, and the expression of adherence genes. Furthermore, the current study showed further step to understand the mechanisms by which graphene nano-sheets can conflict bacterial virulence and resistance.


Assuntos
Infecções por Escherichia coli , Grafite , Antibacterianos/farmacologia , Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Virulência , beta-Lactamases/genética
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