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1.
Molecules ; 27(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36500251

RESUMO

This article reports the synthesis, characterization, geometrical optimization, and biological studies of new MBH-based organometallic compounds of medicinal significance. The ligand (MNHA) was prepared via the Morita-Baylis-Hillman (MBH) synthetic route, from aromatic aldehyde containing multiple functional groups. Metal complexes were prepared in an alkaline medium and under other suitable reaction conditions. Spectral and elemental analyses were used to identify the structural and molecular formulas of each compound. Optimized geometry was determined through density functional theory (DFT) B3LYP and 6-311++ G (d,p) basis set for the MBH adduct, whereas structures of novel complexes were optimized with the semi-empirical PM6 method. Powder XRD analysis furnished the crystal class of complexes, with Co3+, Cr3+, and Mn2+ being cubic, while Ni2+ was hexagonal, and Cu2+ was orthorhombic. Moreover, the ligand, along with Ni2+ and Co3+ complexes, showed profound antibacterial action against S. aureus, E. coli, B. pumilis, and S. typhi. Additionally, all of the complexes were shown to persist in the positive antioxidant potential of the ligand. Contrarily, not a single metal complex conserved the antifungal potentials of the ligand.


Assuntos
Complexos de Coordenação , Staphylococcus aureus , Ligantes , Simulação de Acoplamento Molecular , Testes de Sensibilidade Microbiana , Escherichia coli , Complexos de Coordenação/química , Bases de Schiff/química
2.
Materials (Basel) ; 15(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36363167

RESUMO

The excellent optical properties of gold nanoparticles (AuNPs) make them promising for numerous applications. Herein, we present a facile synthesis of both surfactant-free (SF-AuNPs) and non-toxic D-fructose (DF)-coated gold nanoparticles (DF-AuNPs) via the plasma-liquid interactions (PLIs) method. Moreover, we demonstrate that both SF-AuNPs and DF-AuNPs are potential candidates for trace detection via surface-enhanced Raman scattering (SERS) and catalytic degradation of toxic dyes. However, SF-AuNPs have superior SERS and catalytic performance compared to the DF-AuNPs due to their surfactant-free nature. Moreover, SF-AuNPs have also been shown to quench the fluorescence of analyte molecules, making their SERS-based trace detection more efficient. In particular, SERS enhancement of rhodamine 6G (R6G) and catalytic reduction of a toxic dye methylene blue (MB) have been explored.

3.
Materials (Basel) ; 15(20)2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36295279

RESUMO

This is the first investigation of yttrium (Y) and erbium (Er) co-doped hydroxyapatite (HAp) structures, conducted using theoretical and experimental procedures. By using a wet chemical method, the materials were synthesized by varying the concentration of Y amounts of 0.13, 0.26, 0.39, 0.52, 0.65, and 0.78 at.% every virtual 10 atoms of calcium, whereas Er was kept fixed at 0.39 at.%. Spectroscopic, thermal, and in vitro biocompatibility testing were performed on the generated samples. Theoretical calculations were carried out to compute the energy bandgap, density of states, and linear absorption coefficient. The effects of Y concentration on thermal, morphological, and structural parameters were investigated in detail. Raman and Infrared (FTIR) spectroscopies confirmed the formation of the HAp structure in the samples. Theoretical investigations indicated that the increasing amount of Y increased the density from 3.1724 g cm-3 to 3.1824 g cm-3 and decreased the bandgap energy from 4.196 eV to 4.156 eV, except for the sample containing 0.39 at. % of the dopant, which exhibited a decrease in the bandgap. The values of linear absorption appeared reduced with an increase in photon energy. The samples exhibited cell viability higher than 110%, which revealed excellent biocompatibility for biological applications of the prepared samples.

4.
Materials (Basel) ; 15(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35806623

RESUMO

It is of great significance to design electrochemical energy conversion and storage materials with excellent performance to fulfill the growing energy demand. Bimetallic cobalt/nickel-based electrode materials exhibit excellent electrical conductivity compared to mono oxides. However, their potential as electrode materials for high-performance supercapacitors (SCs) is limited because of their poor cycling stability and high-capacity fading. This work demonstrates the synthesis of binder-free bimetallic NiCo2O4 nano-needles supported on CC (NCO@CC) via a facile and scalable hydrothermal process. Excellent electrical conductivity and interconnected nanostructure of NCO@CC nano-needles provide the fast transfer of electrons with numerous channels for ion diffusion. Owing to such features, the binder-free NCO@CC electrode for SC discloses excellent specific capacitance (1476 Fg-1 at 1.5 Ag-1) with 94.25% capacitance retention even after 5000 cycles. From these outstanding electrochemical performances, it can be inferred that NCO@CC nano-needle array-structured electrodes may be potential candidates for SC applications.

5.
Nanomaterials (Basel) ; 12(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35808009

RESUMO

This study aims to determine the heat transfer properties of a magnetohydrodynamic Prandtl hybrid nanofluid over a stretched surface in the presence of bioconvection and chemical reaction effects. This article investigates the bio-convection, inclined magnetohydrodynamic, thermal linear radiations, and chemical reaction of hybrid nanofluid across stretching sheets. Also, the results are compared with the nanofluid flow. Moreover, the non-Newtonian fluid named Prandtl fluid is considered. Microfluidics, industry, transportation, the military, and medicine are just a few of the real-world applications of hybrid nanofluids. Due to the nonlinear and convoluted nature of the governing equations for the problem, similarity transformations are used to develop a simplified mathematical model with all differential equations being ordinary and asymmetric. The reduced mathematical model is computationally analyzed using the MATLAB software package's boundary value problem solver, Runge-Kutta-fourth-fifth Fehlberg's order method. When compared to previously published studies, it is observed that the acquired results exhibited a high degree of symmetry and accuracy. The velocity profiles of basic nanofluid and hybrid nanofluid are increased by increasing the Prandtl parameters' values, which is consistent with prior observations. Additionally, the concentration and temperature of simple and hybrid nanofluids increase with the magnetic parameter values.

6.
Polymers (Basel) ; 14(10)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35631859

RESUMO

The electrochemical deposition of the composites polyaniline (PANI):polypyrrole (PPy)/activated carbon (AC) and polyaniline (PANI): 3, 4-polyethylenedioxythiophene (PEDOT)/AC films is carried out in this work. The electrochemical character of the fabricated samples is investigated via cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) using a three-electrode setup. The values of the specific capacitance of the composites PANI:PPy/AC and PANI:PEDOT/AC at a current density of 1 Ag-1 are evaluated as 586 Fg-1 and 611 Fg-1, respectively. The values of energy density are 40 Whkg-1 and 2094 Wkg-1, whereas power density is recorded as 44 Whkg-1 and 2160 Wkg-1 for respective composites PANI:PPy/AC and PANI:PEDOT/AC. Moreover, the respective composites appeared to retain cyclic stabilities of 92% and 90%. This study points to the potential of the prepared composites for application as electrodes in supercapacitors.

7.
J Neuroradiol ; 49(4): 311-316, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397949

RESUMO

BACKGROUND: Distal vessel occlusions represent about 25-40% of acute ischemic stroke (AIS), either as primary occlusion or secondary occlusion complicating mechanical thrombectomy (MT) for large vessel occlusion. OBJECTIVE: Our aim was to evaluate safety and effectiveness of MT associated with the best medical treatment (BMT) in the management of AIS patients with distal vessel occlusion in comparison with the BMT alone. METHODS: Retrospective analysis was conducted on AIS patients treated by MT+BMT for primary distal vessel occlusion between 2015 and 2020, and were compared with a historic cohort managed by BMT alone between 2006 and 2015 selected based on the same inclusion criteria. A secondary analysis was conducted using propensity score matching (PSM) including the following: NIHSS, age and treatment with intravenous thrombolysis (IVT) as covariates. RESULTS: Of 650 patients screened, 44 patients with distal vessel occlusions treated by MT+BMT were selected and compared with 36 patients who received BMT alone. After PSM, 28 patients in each group were matched without significant difference. Good clinical outcome defined as mRS≤2 was achieved by 53.6% of the MT+BMT group and 57% of the BMT group (OR, 0.87; 95%CI, 0.3-2.4; p = 1.00). The mortality rate was comparable in both groups (7% vs. 10.7% in MT+BMT and BMT patients, respectively; OR=0.64; 95%CI, 0.1-4; p = 1.00). Symptomatic intracranial hemorrhage (ICH) was seen in only one patient treated by MT+BMT (3.6%). CONCLUSION: Mechanical thrombectomy seems to be comparable with the best medical treatment regarding the effectiveness and safety in the management of patients with distal vessel occlusions.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Trombectomia/efeitos adversos , Resultado do Tratamento
8.
Molecules ; 28(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36615478

RESUMO

To satisfy the ever-increasing energy demands, it is of the utmost importance to develop electrochemical materials capable of producing and storing energy in a highly efficient manner. Titanium dioxide (TiO2) has recently emerged as a promising choice in this field due to its non-toxicity, low cost, and eco-friendliness, in addition to its porosity, large surface area, good mechanical strength, and remarkable transport properties. Here, we present titanium dioxide nanoplates/polyvinylidene fluoride (TiO2/PVDF) membranes prepared by a straightforward hydrothermal strategy and vacuum filtration process. The as-synthesized TiO2/PVDF membrane was applied for energy storage applications. The fabricated TiO2/PVDF membrane served as the negative electrode for supercapacitors (SCs). The electrochemical properties of a TiO2/PVDF membrane were explored in an aqueous 6 M KOH electrolyte that exhibited good energy storage performance. Precisely, the TiO2/PVDF membrane delivered a high specific capacitance of 283.74 F/g at 1 A/g and maintained capacitance retention of 91% after 8000 cycles. Thanks to the synergistic effect of TiO2 and PVDF, the TiO2/PVDF membrane provided superior electrochemical performance as an electrode for a supercapacitor. These superior properties will likely be used in next-generation energy storage technologies.


Assuntos
Polivinil , Titânio , Polivinil/química , Titânio/química , Água
9.
Eur J Pharmacol ; 897: 173920, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33571535

RESUMO

Hepatic ischemia-reperfusion (HIR) injury is a common pathophysiological process in many clinical settings. This study was designed to compare the protective role of octreotide (somatostatin analogue, OCT) and melatonin (N-acetyl-5-methoxytryptamine, MLT) through the modulation of autophagy against HIR injury in rats. Male albino rats were divided into sham, HIR, OCT at three doses (50, 75, and 100 µg/kg), MLT, MLT + OCT75, compound C (AMPK inhibitor, CC), and CC + OCT75 groups. Ischemia was induced for 30 min followed by 24 h reperfusion. Biochemical, histopathological, immunohistochemical, lipid peroxidation, ELISA, qPCR, and western blot techniques were performed in our study. Liver autophagy was restored by OCT at doses (50 or 75 µg/kg) as indicated by elevating the expressions of Beclin-1, ATG7, and LC3 accompanied by the reduction of p62 expression through induction of AMPK/S317-ULK1 and inhibition of PI3K/AKT/mTOR/S757-ULK1 signaling pathways. As well, OCT maintained the integrity of the Keap1-Nrf2 system for the normal hepatic functions via controlling the Keap1 turnover through autophagy in a p62-dependent manner, resulting in upholding a series of anti-oxidant and anti-inflammatory cascades. These effects were abolished by compound C. On the other hand, MLT showed a decrease in the autophagy markers via inhibiting AMPK/pS317-ULK1 and activating PI3K/AKT/mTOR/pS757-ULK1 pathways. Autophagy inhibition with MLT markedly reversed the hepatoprotective effects of OCT75 after HIR injury. Finally, our results proved for the first time that OCT75 was more effective than MLT as it was sufficient to induce protective autophagy in our HIR model, which led to the induction of Nrf2-dependent AMPK/autophagy pathways.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Melatonina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Octreotida/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Modelos Animais de Doenças , Fígado/enzimologia , Fígado/patologia , Hepatopatias/enzimologia , Hepatopatias/genética , Hepatopatias/patologia , Masculino , Fator 2 Relacionado a NF-E2/genética , Fosfatidilinositol 3-Quinase/genética , Ratos , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Serina-Treonina Quinases TOR/genética
10.
Toxicol Appl Pharmacol ; 410: 115340, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33264646

RESUMO

BACKGROUND AND AIM: The Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB)/NLRP3 inflammasome signaling pathway is essential in the pathogenesis of hepatic ischemia/ reperfusion (HIR) injury. Pyroptosis is a proinflammatory programmed cell death that is related to several diseases. Thus, the purpose of this study was to examine whether pretreatment with octreotide (somatostatin analogue, OCT) at different doses or OCT at 75µg/kg combined with melatonin (N-acetyl-5-methoxytryptamine, MLT) can alleviate HIR injury via targeting NLRP3 inflammasome-induced pyroptosis in a TLR4/MyD88/NF-κB dependent manner. METHODS: Rats were randomized into sham, HIR, OCT (50, 75, and 100 µg/kg), MLT, and MLT + OCT75 groups. Ischemia was induced via occlusion of the portal triad for 30 min followed by 24 h reperfusion. RESULTS: OCT pretreatment at doses (50 or 75 µg/kg), MLT alone, and MLT + OCT75 significantly ameliorated the biochemical with histopathological changes, oxidative stress, inflammation, apoptosis, then augmented anti-oxidant and anti-apoptotic markers through downregulation of HMGB1, TLR4, MyD88, TRAF-6, p-IκBα (S32), p-NF-κBp65 (S536), NLRP3, ASC, caspase-1(p20), and GSDMD-N expressions compared with HIR group. CONCLUSION: OCT at doses (50 or 75 µg/kg) showed for the first time a hepatoprotective effect against HIR injury via inhibiting TLR4-NLRP3-mediated pyroptosis in rats. As well, OCT75 was more effective than OCT50 or MLT alone, and its effect was not enhanced after the addition of MLT, through downregulation of TLR4/MyD88/NF-κB/NLRP3 inflammasome pathway.


Assuntos
Melatonina/administração & dosagem , NF-kappa B/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Octreotida/administração & dosagem , Piroptose/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Antioxidantes/administração & dosagem , Quimioterapia Combinada , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/fisiologia , Distribuição Aleatória , Ratos , Traumatismo por Reperfusão/metabolismo , Receptor 4 Toll-Like/metabolismo
11.
J Neuroradiol ; 47(6): 404-409, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32910987

RESUMO

BACKGROUND: Tandem basilar artery occlusions (tBAO) are defined as concomitant basilar artery and extracranial dominant vertebral artery occlusions. The prognosis of such tBAO treated by mechanical thrombectomy (MT) has been scantly reported. The purpose of our study was to compare the safety and effectiveness of MT for patients with tBAO compared to those with non-tandem basilar artery occlusions (ntBAO). PATIENTS AND METHODS: Retrospective analysis of a database of patients who underwent MT at two academic centres. All patients treated for BAO were retrieved. Patients with tBAO, defined as a concomitant BAO and extracranial vertebral artery (VA) occlusion or severe stenosis ≥70% (V1 or proximal V2 segment) were compared with patients with ntBAO. RESULTS: A total of 15 patients with tBAO and 74 patients with ntBAO were enrolled. Successful reperfusion (modified thrombolysis in cerebral infarction score ≥2b) was obtained in 73.3% versus 90.5% (OR = 0.29, 95%CI: 0.07-1.15), good clinical outcome (3-months modified Rankin scale ≤2) was reached by 26.7% versus 32.4% (OR = 0.76; 95% CI: 0.24-2.63) and mortality at 3-months was 46.7% versus 31% (OR = 1.94; 95%CI: 0.63-6) of patients with tBAO versus ntBAO, respectively. Two patients (13.3%) with tBAO and three (4%) with ntBAO had symptomatic intracranial haemorrhage (OR = 3.64; 95% CI: 0.55-24). CONCLUSION: Mechanical thrombectomy for patients with tandem basilar artery occlusion tends to be associated with lower rates of successful reperfusion and good clinical outcome, and higher rate of mortality. Larger multicentre studies are warranted to better precise the proper selection and management of such patients.


Assuntos
Trombectomia/métodos , Insuficiência Vertebrobasilar/cirurgia , Idoso , Angiografia Digital , Artéria Basilar , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artéria Vertebral , Insuficiência Vertebrobasilar/diagnóstico por imagem , Insuficiência Vertebrobasilar/mortalidade
12.
Biomed Pharmacother ; 89: 1196-1206, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28320086

RESUMO

Chronic alcohol consumption leads to extracellular matrix hyperplasia and liver fibrosis with a great role of hepatic stellate cell (HSC) activation in this process. The present study was designed to investigate the possible protective effects of diethylcarbamazine (DEC) (50mg/kg, acting as an anti-inflammatory drug, interferes with the arachidonic acid metabolism) when administrated in combination with hesperidin (HDN) (200mg/kg, a flavanone glycoside with potent antioxidant and anti-inflammatory activities) against alcoholic liver fibrosis in wistar rats compared to silymarin (Sil) (100mg/kg). Liver fibrosis was induced in rats using ethanol (EtOH) (1ml/100g/day, p.o.) twice a week for seven weeks. Then, tissue and blood samples were collected to assess the protective effect of DEC+HDN combination. Our results indicated that DEC when combined with HDN blunted EtOH-induced necroinflammation and elevation of liver injury parameters in serum. Besides, attenuated EtOH- induced liver fibrosis, as demonstrated by hepatic histopathology scoring and 4-hydroxyproline content. The mechanisms behind these beneficial effects of both DEC and HDN were also elucidated. These include (1) counteracting hepatic oxidative stress and augmenting hepatic antioxidants; (2) inhibiting the activation of NF-κB as indicated by preventing release of hepatic IL6; (3) preventing the activation of hepatic stellate cells (HSCs), as denoted by reducing a-smooth muscle actin (a-SMA) expression in the liver; and (4) inhibiting the fibrogenesis response of HSCs, as indicated by inhibiting serum transforming growth factor-b1 (TGF-b1). Our study indicates a novel hepatoprotective effect when DEC was co-administered with HDN against liver fibrosis.


Assuntos
Dietilcarbamazina/farmacologia , Etanol/farmacologia , Hesperidina/farmacologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Animais , Antioxidantes/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hidroxiprolina/metabolismo , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Silimarina/farmacologia
13.
Int Sch Res Notices ; 2014: 184278, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27350986

RESUMO

A double-blinded parallel randomized controlled clinical trial was conducted on two groups of colorectal cancer patients to study the therapeutic benefit of orally administered bovine lactoferrin (bLF) on colorectal cancer patients having age ranges from 20 to 71 years and who received 5-fluorouracil and leucovorin calcium. Test group (15 patients) received oral bLF 250 mg/day beside chemotherapy for three months. Control group (15 patients) received chemotherapy only. Serum lactoferrin (LF), serum glutathione-s-transferase enzyme (GST), interferon gamma (INF-γ), tumor marker carcinoembryonic antigen (CEA), renal function tests, hepatic function tests, and complete blood count were measured for both groups before and at the end of the trial. Although, there was a significant effect of oral bLF (250 mg/day) that indicated a significant improvement in mean percent of change of all parameters 3 months after treatment, there was no significant difference between results of patients in the test group and patients in the control group after treatment. This result suggests that oral bLF has significant therapeutic effect on colorectal cancer patients. Our study suggests that daily administration of bLF showed a clinically beneficial effect to colorectal cancer patients with better disease prognosis but that needs further looking into.

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