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1.
Artigo em Inglês | MEDLINE | ID: mdl-38184097

RESUMO

Endoscopic submucosal dissection (ESD) is a minimally invasive treatment for superficial gastrointestinal (GI) cancers.1,2 ESD practice is expanding significantly in the United States and Western countries. This is attributed to a shorter hospital stay, better quality of life, and fewer adverse events compared with surgery. In the United States, ESD usually is performed and managed in an outpatient setting (ambulatory ESD) or with an overnight hospital stay. This practice is in contrast to Eastern Asian countries, where 3 to 5 days of hospital stay is a routine process for observation after ESD. A Swedish study showed that patients with well-selected colorectal neoplasms (median tumor size, 37 mm) could be managed safely in an outpatient setting after ESD.3 A North American multicenter ESD study also reported that ambulatory ESD was safe and feasible in selected cases (noninvasive cancers, no adverse events, high-volume endoscopists with short procedure time).4 However, procedural and technical aspects that enable safe outpatient management of patients after ESD need to be investigated.

2.
Am J Gastroenterol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912697

RESUMO

BACKGROUND: Hybrid endoscopic submucosal dissection (H-ESD) which utilizes ESD knife along with snare-based resection, has been developed to overcome the technical complexity of conventional ESD (C-ESD). This study aimed to compare the therapeutic outcomes of H-ESD vs. C-ESD for non-pedunculated colorectal lesions ≥20 mm in size. METHODS: We conducted a multicenter randomized controlled trial to compare H-ESD and C-ESD (Short-ESD trial). Patients with colorectal lesions between 20-50 mm in size were randomly assigned (1:1) to H-ESD or C-ESD. Primary outcome was procedure time/speed. Secondary outcomes were en-bloc and complete (R0) resection rates and adverse event rates. RESULTS: A total of 89 patients (median age 63 years; 49.3% women) with median polyp size 30 mm underwent H-ESD (n=40) and C-ESD (n=49). The mean procedure time of H-ESD was significantly shorter than that of C-ESD (41.1±16.3 vs. 54.3±28.2 minutes; p=0.007). The en-bloc and R0 resection rates trended lower in the H-ESD vs C-ESD groups (77.5% vs. 87.8%; p=0.26 and 72.5% vs. 79.6%; p=0.46) without reaching statistical significance. Adverse event rate was similar between H-ESD and C-ESD (10% vs 8.2%; p=1.00). CONCLUSION: Both H-ESD and C-ESD were safe and effective for resection of large colorectal lesions. H-ESD was associated with a shorter procedure time. H-ESD may represent a viable alternative to C-ESD, with the main advantage being easy applicability of a snare-based technique for colorectal lesions. Future studies are needed to further define the most suitable lesions for H-ESD, as to optimize efficiency and safety without compromising resection outcomes. ClinicaTrials.gov NCT NCT05347446.

3.
Gastrointest Endosc ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38467200

RESUMO

BACKGROUND AND AIMS: Post-operative stricture is serious common adverse event following extensive endoscopic submucosal dissection (ESD) in the esophagus. The self-assembling peptide (SA) gel has been shown to promote tissue healing and re-epithelialization. We aimed to evaluate the effect of the SAP gel for esophageal stricture prevention after ESD. METHODS: Multicenter prospective study of patients who underwent esophageal ESD followed by SAP gel application between March 2022 to December 2023. Patients were included if ESD mucosal defect involved ≥ 50% of the circumference of the esophagus. High-risk cases were defined as mucosal defects ≥75% of the circumference. Stricture was defined as the inability to pass an endoscope ≥8.9 mm in diameter or a narrow-caliber lumen in a patient with symptoms. RESULTS: A total of 43 patients (median age 71 years; 81.4% men) underwent ESD (median resected specimen size 50 mm) during the study period. SAP gel (median 3 mL) was successfully applied in all cases (median time 4 minutes). In aggregate, stricture occurred in 20.9% (9/43) of the cases. Stricture developed in 30.8% of the high-risk cases: 80% (4/5) after circumferential ESD and 19% (4/21) in those with defects ≥75% but <100% of the circumference. All cases of stricture resolved with endoscopic treatment. Three cases (6.9%) of postoperative bleeding occurred and were adequately managed endoscopically. CONCLUSION: We demonstrate that SAP gel application was easy, quick, and associated with a relatively low stricture rate comparable to other prophylactic methods. Additional comparative studies are needed to corroborate these preliminary findings.

4.
Gastrointest Endosc ; 99(1): 83-90.e1, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37481003

RESUMO

BACKGROUND AND AIMS: Complete closure after endoscopic resection of large nonpedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual-action tissue (DAT) clip has clip arms that open and close independently of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after endoscopic resection of LNPCLs. METHODS: This was a multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip after EMR or endoscopic submucosal dissection (ESD) of LNPCLs ≥20 mm from July 2022 to May 2023. Delayed bleeding was defined as a bleeding event requiring hospitalization, blood transfusion, or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas <3 mm along the closure line. RESULTS: One hundred seven patients (median age, 64 years; 42.5% women) underwent EMR (n = 63) or ESD (n = 44) of LNPCLs (median size, 40 mm; 74.8% right-sided colon) followed by defect closure. Complete closure was achieved in 96.3% (n = 103) with a mean of 1.4 ± .6 DAT clips and 2.9 ± 1.8 TTS clips. Delayed bleeding occurred in 1 patient (.9%) without requiring additional interventions. CONCLUSIONS: The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after endoscopic resection of large LNPCLs and was associated with a .9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings. (Clinical trial registration number: NCT05852457.).


Assuntos
Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Prospectivos , Hemorragia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Instrumentos Cirúrgicos , Mucosa Intestinal/cirurgia , Mucosa Intestinal/patologia , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Resultado do Tratamento , Estudos Retrospectivos
5.
Gastrointest Endosc ; 99(6): 924-930, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184116

RESUMO

BACKGROUND AND AIMS: Opioid-induced esophageal dysfunction (OIED) often presents as spastic esophageal disorders (SEDs) and esophagogastric junction outflow obstruction (EGJOO). The aim of this study was to evaluate and compare clinical outcomes of peroral endoscopic myotomy (POEM) for SEDs and EGJOO among opioid users and nonusers. METHODS: This propensity score (PS) matching study included consecutive opioid users and nonusers who underwent POEM for SEDs and EGJOO between January 2018 and September 2022. The following covariates were used for the PS calculation: age, sex, duration of symptoms, Eckardt score, type of motility disorder, and length of myotomy during POEM. Clinical response was defined as a post-POEM Eckardt score ≤3. RESULTS: A total of 277 consecutive patients underwent POEM during the study period. PS matching resulted in the selection of 64 pairs of patients strictly matched 1:1 (n = 128) with no statistically significant differences in demographic, baseline, or procedural characteristics or in the parameters considered for the PS between the 2 groups. Clinical response to POEM was significantly lower among opioid users (51 of 64 [79.7%]) versus nonusers (60 of 64 [93.8%]) (P = .03) at a median follow-up of 18 months. Among opioid users, higher opioid dose (>60 morphine milligram equivalents per day) was associated with a higher likelihood of failure to respond to POEM (odds ratio, 4.59; 95% confidence interval, 1.31-3.98; P = .02). CONCLUSIONS: Clinical response to POEM for SEDs and EGJOO is significantly lower among opioid users versus nonusers. There was a dose-relationship between opioids and response to POEM, with higher daily opioid usage associated with a higher likelihood of treatment failure.


Assuntos
Transtornos da Motilidade Esofágica , Miotomia , Pontuação de Propensão , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Transtornos da Motilidade Esofágica/cirurgia , Miotomia/métodos , Miotomia/efeitos adversos , Analgésicos Opioides/uso terapêutico , Cirurgia Endoscópica por Orifício Natural/métodos , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Esofagoscopia/métodos
6.
Luminescence ; 39(5): e4753, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38698700

RESUMO

A simple and environmentally friendly method was developed for smart and efficient waterborne polyurethane (PUR) paint. Sugarcane bagasse was recycled into reduced graphene oxide nanosheets (rGONSs). Both lanthanide-doped aluminate nanoparticles (LAN; photoluminescent agent, 7-9 nm) and rGONSs (reinforcement agent) were integrated into a waterborne polyurethane to produce a novel photoluminescent, hydrophobic, and anticorrosive nanocomposite coating. Using ferrocene-based oxidation under masked circumstances, graphene oxide nanosheets were produced from sugarcane bagasse. The oxidized semicarbazide (SCB) nanostructures were integrated into polyurethane coatings as a drying, anticorrosion, and crosslinking agent. Polyurethane coatings with varying amounts of phosphor pigment were prepared and subsequently applied to mild steel. The produced paints (LAN/rGONSs@PUR) were tested for their hydrophobicity, hardness, and scratch resistance. Commission Internationale de l'éclairage (CIE) Laboratory parameters and photoluminescence analysis established the opacity and colourimetric properties of the nanocomposite coatings. When excited at 365 nm, the luminescent transparent paints emitted a strong greenish light at 517 nm. The anticorrosion characteristics of the coated steel were investigated. The phosphor-containing (11% w/w) polyurethane coatings displayed the most pronounced anticorrosion capability and long-persistent luminosity. The prepared waterborne polyurethane paints were very photostable and durable.


Assuntos
Grafite , Interações Hidrofóbicas e Hidrofílicas , Nanocompostos , Pintura , Poliuretanos , Poliuretanos/química , Grafite/química , Nanocompostos/química , Luminescência , Corrosão , Química Verde
7.
Chem Biodivers ; : e202400948, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899798

RESUMO

Due to its severe damage, Spodoptera frugiperda is receiving attention as one of the biggest dangers to world food security. Although there are numerous insecticides that are widely and successfully used to control S. frugiperda, they do not have an immediate effect. In our work focusing for synthesized twelve novel benzamide derivatives and examined their insecticidal effectiveness against S. frugiperda larvae in their second & fourth larvae instars, with the aim of further improving the insecticidal activity based on combination principles. Several spectroscopic methods, including elemental analysis, NMR & infrared spectroscopy, were employed for confirming the structure of the newly designed products. It has been discovered that most compounds show good of promising efficacy. With an LC50 of 24.8 mg/L for larvae in the second instar & 56.2 mg/L for larvae in the fourth instar, compound 23 was the most active. Among all compounds 11, 22 and 20 exhibited excellent results. Furthermore, a number of biological and histopathological properties of the demonstration compounds of the produced goods under laboratory conditions were also examined. This work further demonstrates the anti-proliferation of S. frugiperda and offers fresh ideas for the manufacture of benzamide derivatives.

8.
Chem Biodivers ; 21(4): e202400218, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38381590

RESUMO

Certain 2-amino-6-alkoxy-4-arylpyridine-3,5-dicyanide 1a-e were prepared via a straightforward process using microwave technology rather than conventional methods. This involved reaction of arylidenemalononitrile thru propanedinitrile in the occurrence of sodium alkoxide under MW. While, their positional isomer 4-amino-6-alkoxy-2-arylpyridine-3,5-dicyanide 3a-j have been separated from the reaction of aryl aldehydes with 2-aminoprop-1-ene-1,1,3-tricarbonitrile 2 in the presence of sodium alkoxide using microwave technic. Furthermore, the insecticidal properties of all synthesized compounds were observed with respect to Cotton aphid nymphs and adults. Neonicotinoid pesticides are indicated as the most effective pesticides toward aphids and many other pests. Many insecticides are discovered as novelties. As a result, several pyridine compounds were chemical method synthesized to serve as equivalents of neonicotinoids, a broad class of insecticides. With LC50 value of 0.03 mg/L, components 3g exhibit the highest insecticidal bioactivity. This work discusses how to find new chemicals that could be used as insecticidal agents in the future.


Assuntos
Álcoois , Afídeos , Inseticidas , Animais , Inseticidas/química , Micro-Ondas , Neonicotinoides/farmacologia , Sódio/farmacologia
9.
Biochem Biophys Res Commun ; 649: 118-124, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764114

RESUMO

Natural chitosan-based films (CS) were fabricated by changing ingredient corporations between gold nanoparticles (AuNPs), lithium oxide (Li2O), and graphene oxide (GO). A Series of films with different components were obtained. The structural examination is executed by XRD, FTIR, and EDX to analyze crystal structure, chemical bonding, and chemical contents, respectively. The findings illustrated that, the Li2O@CS exhibited the lowest contact angle with 70 ± 4.6°. Scanning Electron Microscopy (SEM) displayd rod-shaped AuNPs with an average length of 0.3 µm and an average width of 90 nm. The refractive index of CS recorded 2.142, while AuNPs/Li2O/GO@CS slightly declined to 2.085. Concerning AuNPs/Li2O/GO@CS, the detected cell viability percentage of normal lung cells among the usage of 156.25 µg/mL is 98.91%, while 9.77 µg/mL achieved 125.78%. Therefore, combining AuNPs, GO and Li2O within the CS matrix results in films of boosted biocompatibility and can be suggested for medical applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Quitosana/química , Ouro/química , Óxidos , Lítio , Sobrevivência Celular , Nanopartículas Metálicas/química
10.
Gastrointest Endosc ; 98(3): 381-391, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37061137

RESUMO

BACKGROUND AND AIMS: Endoscopic suturing enables full closure of large defects after endoscopic submucosal dissection (ESD). However, its use is limited by the need for a double-channel endoscope. A novel closure system, the OverStitch Sx (Apollo Endosurgery, Austin, Tex, USA), compatible with any single-channel endoscope, was introduced to address these shortcomings. The aim of this study was to assess the safety and feasibility of OverStitch Sx for the closure of large defects after ESD. METHODS: This is a prospective single-center feasibility study of patients who underwent closure of large defects after ESD using the OverStitch Sx system. Main outcomes of the study are technical and clinical success, same-day discharge rate, and adverse event rate. RESULTS: Thirty-three patients were enrolled. The mean diameter of included lesions was 5.38 ± 2.52 cm. The defect occupied ≥50% of the lumen circumference in 70% of the cases. En-bloc resection, R0 resection, and curative resection were achieved in 97%, 87.5%, and 78.8% of patients, respectively. Technical success and clinical success were seen in 93.9% and 90.9% of the cases, respectively. Same-day hospital discharge was achieved in 77.4% of patients. Total adverse event rate was 35.7%, including delayed bleeding in 1 patient after rectal ESD that was managed conservatively, self-resolving rectal pain in 7 patients, rectal stricture requiring dilation in 1 patient, and temporary dysphagia in 1 patient. No immediate or delayed perforation was reported. CONCLUSIONS: OverStitch Sx enabled safe and effective closure of large defects after ESD. Future trials are needed to determine its superiority over OverStitch for the closure of defects in challenging locations. (Clinical trial registration number: NCT04361227.).


Assuntos
Ressecção Endoscópica de Mucosa , Humanos , Ressecção Endoscópica de Mucosa/efeitos adversos , Estudos Prospectivos , Reto , Resultado do Tratamento , Estudos Retrospectivos
11.
Chem Biodivers ; 20(11): e202301018, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37695826

RESUMO

Bacterial infections that cause chronic wounds provide a challenge to healthcare worldwide because they frequently impede healing and cause a variety of problems. In this study, loaded with tungsten oxide (WO3 ), Magnesium oxide (MgO), and graphene oxide (GO) on chitosan (CS) membrane, an inexpensive polymer casting method was successfully prepared for wound healing applications. All fabricated composites were characterized by X-ray powder diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). A scanning electron microscope (SEM) was used to study the synthesized film samples' morphology as well as their microstructure. The formed WO3/MgO@CS shows a great enhancement in the UV/VIS analysis with a highly intense peak at 401 nm and a narrow band gap (3.69 eV) compared to pure CS. The enhanced electron-hole pair separation rate is responsible for the WO3/MgO/GO@CS scaffold's antibacterial activity. Additionally, human lung cells were used to determine the average cell viability of nanocomposite scaffolds and reached 121 % of WO3 /MgO/GO@CS nanocomposite, and the IC50 value was found to be 1654 µg/mL. The ability of the scaffold to inhibit the bacteria has been tested against both E. coli and S. aureus. The 4th sample showed an inhibition zone of 11.5±0.5 mm and 13.5±0.5 mm, respectively. These findings demonstrate the enormous potential for WO3 /MgO/GO@CS membrane as wound dressings in the clinical management of bacterially infected wounds.


Assuntos
Quitosana , Grafite , Humanos , Quitosana/química , Tungstênio/química , Grafite/química , Óxido de Magnésio , Magnésio , Staphylococcus aureus , Espectroscopia de Infravermelho com Transformada de Fourier , Escherichia coli , Óxidos/química , Antibacterianos/farmacologia , Antibacterianos/química
12.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677536

RESUMO

A new series of Schiff-benzimidazole hybrids 3a-o has been designed and synthesized. The structure of the target compounds was proved by different spectroscopic and elemental analysis tools. The target compounds were evaluated for their in vitro cytotoxic activity against 60 cancer cell lines according to NCI single- and five-dose protocols. Consequently, four compounds were further examined against the most sensitive lung cancer A549 and NCI-H460 cell lines. Compounds 3e and 3g were the most active, achieving 3.58 ± 0.53, 1.71 ± 0.17 and 1.88 ± 0.35, 0.85 ± 0.24 against A549 and NCI-H460 cell lines, respectively. Moreover, they showed remarkable inhibitory activity on the VEGFR-2 TK with 86.23 and 89.89%, respectively, as compared with Sorafenib (88.17%). Moreover, cell cycle analysis of NCI-H460 cells treated with 3e and 3g showed cellular cycle arrest at both G1 and S phases (supported by caspases-9 study) with significant pro-apoptotic activity, as indicated by annexin V-FITC staining. The binding interactions of these compounds were confirmed through molecular docking studies; the most active compounds displayed complete overlay with, and a similar binding mode and pose to, Sorafenib, a reference VEGFR-2 inhibitor.


Assuntos
Antineoplásicos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Antineoplásicos/química , Apoptose , Benzimidazóis/química , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Simulação de Acoplamento Molecular , Estrutura Molecular , Bases de Schiff/farmacologia , Sorafenibe/farmacologia , Relação Estrutura-Atividade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
13.
Int J Mol Sci ; 23(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35742870

RESUMO

Coronavirus disease (SARS-CoV-2) is a global epidemic. This pandemic, which has been linked to high rates of death, has forced some countries throughout the world to implement complete lockdowns in order to contain the spread of infection. Because of the advent of new coronavirus variants, it is critical to find effective treatments and vaccines to prevent the virus's rapid spread over the world. In this regard, metal complexes have attained immense interest as antibody modifiers and antiviral therapies, and they have a lot of promise towards SARS-CoV-2 and their suggested mechanisms of action are discussed, i.e., a new series of metal complexes' medicinal vital role in treatment of specific proteins or SARS-CoV-2 are described. The structures of the obtained metal complexes were fully elucidated by different analytical and spectroscopic techniques also. Molecular docking and pharmacophore studies presented that most of complexes studied influenced good binding affinity to the main protease SARS-CoV-2, which also was attained as from the RCSB pdb (Protein Data Bank) data PDB ID: 6 W41, to expect the action of metal complexes in contradiction of COVID-19. Experimental research is required to determine the pharmacokinetics of most of the complexes analyzed for the treatment of SARS-CoV-2-related disease. Finally, the toxicity of a metal-containing inorganic complex will thus be discussed by its capability to transfer metals which may bind with targeted site.


Assuntos
Tratamento Farmacológico da COVID-19 , Complexos de Coordenação , Antivirais/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Controle de Doenças Transmissíveis , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , SARS-CoV-2
14.
Int J Mol Sci ; 23(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35269858

RESUMO

N-(4-((3-Methyl-1,4-dioxo-1,4-dihydronaphthalen-2-yl)selanyl)phenyl)acetamide (5), C19H15NO3Se, was prepared in two steps from 4,4'-diselanediyldianiline (3) via reduction and subsequent nucleophilic reaction with 2-methyl-3-bromo-1,4-naphthalenedione, followed by acetylation with acetic anhydride. The cytotoxicity was estimated against 158N and 158JP oligodendrocytes and the redox profile was also evaluated using different in vitro assays. The technique of single-crystal X-ray diffraction is used to confirm the structure of compound 5. The enantiopure 5 crystallizes in space group P21 with Flack parameter 0.017 (8), exhibiting a chiral layered absolute structure. Molecular structural studies showed that the crystal structure is foremost stabilized by N-H···O and relatively weak C-H···O contacts between molecules, and additionally stabilized by weak C-H···π and Se···N interactions. Hirshfeld surface analysis is used to quantitatively investigate the noncovalent interactions that stabilize crystal packing. Framework energy diagrams were used to graphically represent the stabilizing interaction energies for crystal packing. The analysis of the energy framework shows that the interactions energies of and C-H···π and C-O···π are primarily dispersive and are the crystal's main important forces. Density functional theory (DFT) calculations were used to determine the compound's stability, chemical reactivity, and other parameters by determining the HOMO-LUMO energy differences. The determination of its optimized surface of the molecular electrostatic potential (MEP) was also carried out. This study was conducted to demonstrate both the electron-rich and electron-poor sites.


Assuntos
Halogênios , Hidrogênio , Acetamidas , Cristalografia por Raios X , Teoria da Densidade Funcional , Ligação de Hidrogênio
15.
Int J Mol Sci ; 23(7)2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35409353

RESUMO

Two tetradentate dibasic chelating Schiff base iron (III) chelates were prepared from the reaction of 2,2'-((1E,1'E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene))bis(4-bromophenol) (PDBS) and 2,2'-((1E,1'E)-((4-chloro-1,2-phenylene)bis(azanylylidene))-bis(methanylylidene))bis(4-bromophenol) (CPBS) with Fe3+ ions. The prepared complexes were fully characterized with spectral and physicochemical tools such as IR, NMR, CHN analysis, TGA, UV-visible spectra, and magnetic moment measurements. Moreover, geometry optimizations for the synthesized ligands and complexes were conducted using the Gaussian09 program through the DFT approach, to find the best structures and key parameters. The prepared compounds were tested as antimicrobial agents against selected strains of bacteria and fungi. The results suggests that the CPBSFe complex has the highest activity, which is close to the reference. An MTT assay was used to screen the newly synthesized compounds against a variety of cell lines, including colon cancer cells, hepatic cellular carcinoma cells, and breast carcinoma cells. The results are expressed by IC50 value, in which the 48 µg/mL value of the CPBSFe complex indicates its success as a potential anticancer agent. The antioxidant behavior of the two imine chelates was studied by DPPH assay. All the tested imine complexes show potent antioxidant activity compared to the standard Vitamin C. Furthermore, the in vitro assay and the mechanism of binding and interaction efficiency of the tested samples with the receptor of COVID-19 core protease viral protein (PDB ID: 6lu7) and the receptor of Gram-negative bacteria (Escherichia coli, PDB ID: 1fj4) were investigated using molecular docking experiments.


Assuntos
Tratamento Farmacológico da COVID-19 , Iminas , Quelantes/química , Quelantes/farmacologia , DNA/química , Teoria da Densidade Funcional , Compostos Férricos , Humanos , Iminas/química , Iminas/farmacologia , Simulação de Acoplamento Molecular , Preparações Farmacêuticas
16.
Int J Mol Sci ; 23(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36012623

RESUMO

The corrosion inhibition of transition metal chelates derived from Schiff base ligands was tested for (mild, copper, stainless, aluminum and carbon) steel in various concentrations of (HCl, HNO3 and H2SO4) acidic medium at 25 °C through (weight loss, potentiodynamic polarization, polarization curves, electrochemical impedance spectroscopy (EIS) and open circuit potential measurements (OCP)) techniques. The studied compounds were identified with various spectral, analytical and physico-chemical techniques. It was observed that the investigated compounds had a significant inhibitory impact on the corrosion of diverse steels in the medium investigated. The analysis shows that increasing the dose of the studied complexes improves the corresponding inhibitory efficiency values. Negative results of Gibb's free adsorption energy (ΔGads0) prove the suppression process's spontaneous and physical adsorption, which contradicts the Langmuir adsorption isotherm. As a result of this insight, a novel bridge between nuclearity driven coordinated inorganic chemistry and materials, as well as corrosion control, has been built. This review provides an overview of the use of Schiff bases and associated transition metals as potential corrosion inhibitors, including the factors that influence their application.


Assuntos
Iminas , Aço , Adsorção , Quelantes , Corrosão , Bases de Schiff/química , Aço/química
17.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555272

RESUMO

Novelmanganese(II), iron(III), cobalt(II), nickel(II), and copper(II) chelates were synthesized and studied using elemental analysis (EA), infrared spectroscopy, mass spectrometry, ultraviolet-visible spectroscopy, and conductivity, as well as magnetic measurements and thermogravimetric analysis (TG). The azo-ligand 1-[(4-nitrophenyl)diazenyl]-2-naphthol (HL) chelates to the metal ions via the nitrogen and oxygen centers of the azo group and the hydroxyl, respectively. The amounts of H2O present and its precise position were identified by thermal analysis. Density functional theory (DFT) was employed to theoretically elucidate the molecular structures of the ligand and the metal complexes. Furthermore, the quantum chemical parameters were also evaluated. The antimicrobial properties were evaluated against a group of fungal and bacterial microbes. Interestingly, the bioactivity of the complexes is enhanced compared to free ligands. Within this context, the CuL complex manifested the lowest activity, whereas the FeL complex had the greatest. Molecular docking was used to foretell the drugs' binding affinity for the structure of Escherichia coli (PDB ID: 1hnj). Protein-substrate interactions were resolved, and binding energies were accordingly calculated.


Assuntos
Complexos de Coordenação , Cobre , Cobre/química , Níquel/química , Ferro/química , Manganês/química , Cobalto/química , Simulação de Acoplamento Molecular , Ligantes , Espectrofotometria Infravermelho , Quelantes , Complexos de Coordenação/química
18.
Molecules ; 27(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35458747

RESUMO

Drinking water containing nitrate ions at a higher concentration level of more than 10 mg/L, according to the World Health Organization (WHO), poses a considerable peril to humans. This danger lies in its reduction of nitrite ions. These ions cause methemoglobinemia during the oxidation of hemoglobin into methemoglobin. Many protocols can be applied to the remediation of nitrate ions from hydra solutions such as Zn metal and amino sulfonic acid. Furthermore, the electrochemical process is a potent protocol that is useful for this purpose. Designing varying parameters, such as the type of cathodic electrode (Sn, Al, Fe, Cu), the type of electrolyte, and its concentration, temperature, pH, and current density, can give the best conditions to eliminate the nitrate as a pollutant. Moreover, the use of accessible, functional, and inexpensive adsorbents such as granular ferric hydroxide, modified zeolite, rice chaff, chitosan, perlite, red mud, and activated carbon are considered a possible approach for nitrate removal. Additionally, biological denitrification is considered one of the most promising methodologies attributable to its outstanding performance. Among these powerful methods and materials exist zero-valent iron (ZVI), which is used effectively in the deletion process of nitrate ions. Non-precious synthesis pathways are utilized to reduce the Fe2+ or Fe3+ ions by borohydride to obtain ZVI. The structural and morphological characteristics of ZVI are elucidated using UV-Vis spectroscopy, zeta potential, XRD, FE-SEM, and TEM. The adsorptive properties are estimated through batch experiments, which are achieved to control the feasibility of ZVI as an adsorbent under the effects of Fe0 dose, concentration of NO3- ions, and pH. The obtained literature findings recommend that ZVI is an appropriate applicant adsorbent for the remediation of nitrate ions.


Assuntos
Água Potável , Poluentes Químicos da Água , Humanos , Ferro/química , Nitratos/análise , Óxidos de Nitrogênio , Poluentes Químicos da Água/análise
19.
Molecules ; 27(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36144781

RESUMO

In this study, pumice is used as a novel natural heterogeneous catalyst for the synthesis of 3,4-dihydropyrimidine-2-(1H)-ones/thiones via the one-pot multi-component condensation of aromatic aldehydes, urea/thiourea, and ethyl acetoacetate or acetylacetone in excellent yields (up to 98%). The physical and chemical properties of the catalyst were studied. Their geochemical analysis revealed a basaltic composition. Furthermore, X-ray diffraction showed that it is composed of amorphous materials with clinoptilolite and heulandites zeolite minerals in its pores. Moreover, pumice has a porosity range from 78.2-83.9% (by volume) and is characterized by a mesoporous structure (pore size range from 21.1 to 64.5 nm). Additionally, it has a pore volume between 0.00531 and 0.00781 m2/g and a surface area between 0.053 and 1.47 m2/g. The latter facilitated the reaction to proceed in a short time frame as well as in excellent yields. It is worth noting that our strategy tolerates the use of readily available, cheap, non-toxic, and thermally stable pumice catalyst. The reactions proceeded smoothly under solvent-free conditions, and products were isolated without tedious workup procedures in good yields and high purity. Indeed, pumice can be reused for at least five reuse cycles without affecting its activity.


Assuntos
Tionas , Zeolitas , Aldeídos/química , Catálise , Silicatos , Solventes , Tionas/química , Tioureia/química , Ureia/química
20.
Eur J Dent Educ ; 26(1): 66-75, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33512771

RESUMO

OBJECTIVES: An insight into students' motivation and confidence in the choice of entering and remaining in dental education is essential. The understanding of how choices are made can help universities in the planning of admission policies. This study aimed to evaluate the career choice influences, motivation and confidence in the choices made into dental education. METHODS: A mixed-method design was employed, using both quantitative and qualitative data. One hundred seventy-three questionnaires were distributed to all registered dental students, with a response rate of 85%. The questionnaire explored students' demographics and factors that influenced their career choice. Seven focus groups were facilitated with related data recorded and transcribed verbatim. RESULTS: The quantitative data revealed the desire to help others, and socioeconomic factors were influential, whilst for parents' influence, the mother's influence was statistically significant. Qualitatively, results converged and complemented quantitative data; there was a balance between helping others and socioeconomic and familial influences. There was an increase in confidence in the choice made as students advanced in their dental education. The results indicate that informed awareness of the dental programme structure is essential before embarking on a dental career. CONCLUSIONS: The factors that impacted on choice were helping others, socioeconomic factors and the influence on choice from family. They were generally satisfied with their choice and were confident in the choice they made. This confidence, however, was not reflected until the more advanced clinical stages of their dental education.


Assuntos
Motivação , Estudantes de Odontologia , Escolha da Profissão , Odontologia , Educação em Odontologia , Humanos , Inquéritos e Questionários
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