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1.
ACS Omega ; 9(9): 10090-10098, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463304

RESUMO

In this study, we report the successful synthesis of a phenol-formaldehyde-pyrazole (PF-PYZ) compound through the surface functionalization of phenol-formaldehyde (PF) with pyrazole (PYZ). The resulting mixture was subjected to comprehensive characterization using a range of analytical techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The newly synthesized PF-PYZ material effectively removes Cr(VI) ions. Notably, a substantial elimination efficiency of 96% was achieved after just 60 min of contact time. The strategic incorporation of pyrazole (PYZ) as the principal functionalizing agent contributed to this exceptional performance. Notably, the functionalized PYZ sites were strategically positioned on the surface of PF, rendering them readily accessible to metal ions. Through rigorous testing, the optimal sorption capacity of PF-PYZ for Cr(VI) ions was quantified at 0.872 mmol Cr(VI)/g, highlighting the material's superior adsorption capabilities. The practical utility of PF-PYZ was further established through a reusability test, which demonstrated that the chromate capacity remained remarkably stable at 0.724 mequiv Cr(VI)/g over 20 consecutive cycles. This resilience underscores the robustness of the resin, indicating its potential for repeated regeneration and reuse without a significant capacity loss. Our work presents a novel approach to functionalizing phenol-formaldehyde with pyrazole, creating PF-PYZ, a highly efficient material for removing Cr(VI) ions. The compound's facile synthesis, exceptional removal performance, and excellent reusability collectively underscore its promising potential for various water treatments, especially oil field and environmental remediation applications.

2.
ACS Omega ; 9(6): 6403-6422, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38375499

RESUMO

Nonfullerene-based organic solar cells can be utilized as favorable photovoltaic and optoelectronic devices due to their enhanced life span and efficiency. In this research, seven new molecules were designed to improve the working efficiency of organic solar cells by utilizing a terminal acceptor modification approach. The perceived A2-D-A1-D-A2 configuration-based molecules possess a lower band gap ranging from 1.95 to 2.21 eV compared to the pre-existing reference molecule (RW), which has a band gap of 2.23 eV. The modified molecules also exhibit higher λmax values ranging from 672 to 768 nm in the gaseous and 715-839 nm in solvent phases, respectively, as compared to the (RW) molecule, which has λmax values at 673 and 719 nm in gas and chloroform medium, respectively. The ground state geometries, molecular planarity parameter, and span of deviation from the plane were analyzed to study the planarity of all of the molecules. The natural transition orbitals, the density of state, molecular electrostatic potential, noncovalent interactions, frontier molecular orbitals, and transition density matrix analysis of all studied molecules were executed to validate the optoelectronic properties of these molecules. Improved charge mobilities and dipole moments were observed, as newly designed molecules possessed lower internal reorganization energies. The open circuit voltage (Voc) of W4, W5, W6, and W7 among newly designed molecules was improved as compared to the reference molecule. These results elaborate on the superiority of these novel-designed molecules over the pre-existing (RW) molecule as potential blocks for better organic solar cell applications.

3.
J Biomol Struct Dyn ; 42(1): 244-260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37096830

RESUMO

In the present study, a series of 2-amino-4,6-diarylpyrimidine derivatives was designed, synthesized, characterized and evaluated for their in vitro α-glucosidase and α-amylase enzyme inhibition assays. The outcomes proved that this class of compounds exhibit considerable inhibitory activity against both enzymes. Among the target compounds, compounds 4p and 6p demonstrated the most potent dual inhibition with IC50 = 0.087 ± 0.01 µM for α-glucosidase; 0.189 ± 0.02 µM for α-amylase and IC50 = 0.095 ± 0.03 µM for α-glucosidase; 0.214 ± 0.03 µM for α-amylase, respectively as compared to the standard rutin (IC50 = 0.192 ± 0.02 µM for α-glucosidase and 0.224 ± 0.02 µM for α-amylase). Remarkably, the enzyme inhibition results indicate that test compounds have stronger inhibitory effect on the target enzymes than the positive control, with a significantly lower IC50 value. Moreover, these series of compounds were found to inhibit α-glucosidase activity in a reversible mixed-type manner with IC50 between 0.087 ± 0.01 µM to 1.952 ± 0.26 µM. Furthermore, molecular docking studies were performed to affirm the binding interactions of this scaffold to the active sites of α-glucosidase and α-amylase enzymes. The quantitative structure-activity relationship (QSAR) investigations showed a strong association between 1p-15p structures and their inhibitory actions (IC50) with a correlation value (R2) of 0.999916. Finally, molecular dynamic (MD) simulations were carried out to assess the dynamic behavior, stability of the protein-ligand complex, and binding affinity of the most active inhibitor 4p. The experimental and theoretical results therefore exposed a very good compatibility. Additionally, the drug-likeness assay revealed that some compounds exhibit a linear association with Lipinski's rule of five, indicating good drug-likeness and bioactivity scores for pharmacological targets.Communicated by Ramaswamy H. Sarma.


Assuntos
Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade , Simulação de Acoplamento Molecular , alfa-Glucosidases/química , Relação Estrutura-Atividade , alfa-Amilases , Estrutura Molecular
4.
RSC Adv ; 13(36): 24887-24898, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37614786

RESUMO

Sugar beet crown (SBC) waste was employed to produce sustainable activated carbon (AC) by a thermo-chemical activation procedure using a fixed ratio of H3PO4/SBC (1 : 1 w/w ratio) at 550 °C/2 h. An activated carbon/polyamide nano-composite (AC/PA) was also prepared through the polymerization of the fabricated AC (90%) with polyamide (PA, 10%) synthetic textile waste using a proper dissolving agent at a specified w/w ratio with the employed polymer (formic acid/PA = 82/18%). Both AC and its derivative AC/PA were employed in the remediation of dyes from industrial wastewater in column systems, and their efficiencies were compared at various applied experimental conditions. The adsorption of the industrial dye waste (IDW) was a pH-, flow rate-, and bed thickness-controlled process by the regarded adsorbents. Kinetic studies confirmed the suitability of the Thomas equation over the Yoon and Nelson model in predicting the dynamic adsorption process of IDW by AC and AC/PA as was assured by the close agreement among the calculated and experimental uptake capacities of both adsorbents at the same applied flow rates, suggesting the chemisorption nature of IDW adsorption. Additionally, electrostatic attraction was the leading mechanism of IDW adsorption by AC and AC/PA composite with some advantages of the former over the latter.

5.
Results Phys ; 27: 104509, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34307005

RESUMO

COVID-19 was declared a global pandemic by the World Health Organization in March 2020, and has infected more than 4 million people worldwide with over 300,000 deaths by early May 2020. Many researchers around the world incorporated various prediction techniques such as Susceptible-Infected-Recovered model, Susceptible-Exposed-Infected-Recovered model, and Auto Regressive Integrated Moving Average model (ARIMA) to forecast the spread of this pandemic. The ARIMA technique was not heavily used in forecasting COVID-19 by researchers due to the claim that it is not suitable for use in complex and dynamic contexts. The aim of this study is to test how accurate the ARIMA best-fit model predictions were with the actual values reported after the entire time of the prediction had elapsed. We investigate and validate the accuracy of an ARIMA model over a relatively long period of time using Kuwait as a case study. We started by optimizing the parameters of our model to find a best-fit through examining auto-correlation function and partial auto correlation function charts, as well as different accuracy measures. We then used the best-fit model to forecast confirmed and recovered cases of COVID-19 throughout the different phases of Kuwait's gradual preventive plan. The results show that despite the dynamic nature of the disease and constant revisions made by the Kuwaiti government, the actual values for most of the time period observed were well within bounds of our selected ARIMA model prediction at 95% confidence interval. Pearson's correlation coefficient for the forecast points with the actual recorded data was found to be 0.996. This indicates that the two sets are highly correlated. The accuracy of the prediction provided by our ARIMA model is both appropriate and satisfactory.

6.
Int J Pharm ; 593: 120143, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33279712

RESUMO

The development of a scaffold matrix that can inhibit bacterial infection and promote wound healing simultaneously is an essential demand to improve the health care system. Hydroxyapatite (HAP) doped with different concentrations of silver ions (Ag+) were incorporated into electrospun nanofibrous scaffolds of polycaprolactone (PCL) using the electrospinning technique. The formed phase was identified using XRD, while the morphological and roughness behavior were investigated using FESEM. It was shown that scaffolds were configured in randomly distributed nanofibers with diameters around of 0.19-0.40, 0.31-0.54, 1.36, 0.122-0.429 µm for 0.0Ag-HAP@PCL, 0.2Ag-HAP@PCL, 0.6Ag-HAP@PCL, and 0.8Ag-HAP@PCL, respectively. Moreover, the maximum roughness peak height increased significantly from 179 to 284 nm, with the lowest and highest contributions of Ag. The mechanical properties were examined and displayed that the tensile strength increased from 3.11 ± 0.21 MPa to its highest value at 3.57 ± 0.31 MPa for 0.4Ag-HAP@PCL. On the other hand, the cell viability also was enhanced with the addition of Ag and improved from 97.1 ± 4.6% to be around 102.3 ± 3.1% at the highest contribution of Ag. The antibacterial activity was determined, and the highest imbibition zones were achieved at the highest Ag dopant to be 12.5 ± 1.1 mm and 11.4 ± 1.5 mm against E. coli and S. aureus. The in vitro cell proliferation was observed through human fibroblasts cell lone (HFB4) and illustrated that cells were able to grow and spread not only on the fibers' surface but also, they were spreading and adhered through the deep pores.


Assuntos
Durapatita , Nanofibras , Antibacterianos/farmacologia , Bandagens , Adesão Celular , Escherichia coli , Humanos , Poliésteres , Prata , Staphylococcus aureus , Alicerces Teciduais
7.
J Diet Suppl ; 14(1): 54-64, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27494173

RESUMO

The objective of this work was to evaluate the beneficial effect of α-lipoic acid (ALA) and L-carnitine (CAR) on insulin sensitivity and anti-inflammatory markers in animal model of metabolic syndrome (MS), high fructose (HF)-fed rats. Forty male rats were randomly divided into four groups (n = 10). Group 1(control rats, G1), animals were allowed to drink 0.2% gum acacia (GA, p.o) and were fed a modified diet containing 65% cornstarch. The remaining rats were induced MS by feeding the same diet + free access to 10% fructose (w/v) in 0.2% GA (HF, MS) for 4 weeks. After 4 weeks of HF feeding, the rats were further divided into three subgroups; G2: HF (MS) in 0.2% GA, G3: HF (MS)+CAR (200 mg/kg/day) in 0.2% GA and G4: HF (MS)+ALA (200 mg/kg/day) in 0.2% GA, respectively. All ingredients were administered orally by guava daily for four weeks. A significant increase in serum glucose, insulin and Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) levels was observed after four weeks of HF feeding compared to control rats. Administration of ALA and CAR reversed the increase of the mentioned parameters. In HF rats, the increase of serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels were significantly lowered, while the reduction of the serum high-density lipoprotein cholesterol (HDL-C) was alleviated after administration of CAR and ALA. The reduction of the serum adiponectin level was significantly increased after administration of CAR and ALA. These data suggested that CAR and/or ALA had a beneficial role in the prevention of MS associated with development of type 2 diabetes.

8.
Neurosciences (Riyadh) ; 8(4): 233-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23648886

RESUMO

OBJECTIVE: Topiramate (TPM) is a new antiepileptic drug, which has a wide spectrum of activities suggesting a potentially valuable therapeutic profile. Our objective is to report our experience in treating children with intractable epilepsy. METHODS: Prospective, open label, add on trial of TPM in treating consecutive children with intractable epilepsy (defined as recurrent seizures after at least 3 antiepileptic medication trials) seen between May 1, 1999 and April 28, 2002 at King Faisal Specialist Hospital and Research Centre and King Abdulaziz University Hospital in Jeddah, Kingdom of Saudi Arabia. Follow up by 2 pediatric neurologists was performed. Therapeutic response was recorded as complete (no seizures), good (>50% seizure reduction), fair (<50% seizure reduction), or none. RESULTS: Sixty-two children (36 males and 26 females) aged between 2 months and 16 years (mean 6 years) were treated with TPM and followed for up to 3 years (mean 15 months). Most children (55%) had daily seizures and were tried on multiple antiepileptic drugs (mean 4.6). Nineteen (31%) children had Lennox-Gastaut syndrome. After the introduction of TPM, 21 (34%) became completely seizure free and 24 (39%) had >50% seizure reduction. Children with daily seizures were reduced from 55% before TPM to 13% on TPM (p=0.0007). Side effects were reported in 21 (34%) children in the form of decreased appetite, weight loss, and sedation. The majority was transient; however, TPM had to be withdrawn in 7 (11%) children because of progressive weight loss or seizure worsening. Follow up renal ultrasound was performed on 34 (55%) children and was always normal. CONCLUSION: Topiramate is a very effective antiepileptic drug with a broad spectrum of antiepileptic activities. Most side effects were transient, however, careful monitoring of body weight is recommended.

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