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1.
Chem Biodivers ; 21(7): e202400313, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38467571

RESUMEN

The aim of this study involves the synthesis novel thiophene analogues that can be used as anticancer medications through a strategic multicomponent reaction connecting ethyl 4-chloroacetoacetate (1), phenyl isothiocyanate, and a series of active methylene reagents, including ethyl acetoacetate (2), malononitrile, ethyl cyanoacetate, cyanoacetamide 6a-c, N-phenyl cyanoacetamide derivatives 13a-c, and acetoacetanilide derivatives 18. This reaction was facilitated by dry dimethylformamide with a catalytic quantity of K2CO3. The resultant thiophene derivatives were identified as 4, 8a-b, 9, 12a-d, 15a-c, and 20a-b. Further reaction of compound 4 with hydrazine hydrate yielded derivative 5, respectively. When compound 1 was refluxed with ethyl 3-mercapto-3-(phenylamino)-2-(p-substituted phenyldiazenyl)acrylate 10a-e in the presence of sodium ethoxide, it produced thiophene derivatives 12a-d. Comprehensive structural elucidation of these newly synthesized thiophene-analogues was accomplished via elemental and spectral analysis data. Furthermore, the study delves into the cytotoxicity of the newly synthesized thiophenes was evaluated using the HepG2, A2780, and A2780CP cell lines. The amino-thiophene derivative 15b exhibited an increased growth inhibition of A2780, and A2780CP with IC50 values 12±0.17, and 10±0.15 µM, respectively compared to Sorafenib with IC50 values 7.5±0.54 and 9.4±0.14. This research opens new avenues for developing thiophene-based anticancer agents.


Asunto(s)
Antineoplásicos , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Tiofenos , Humanos , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Estructura Molecular , Relación Estructura-Actividad , Tiofenos/química , Tiofenos/farmacología , Tiofenos/síntesis química
2.
Int J Environ Health Res ; 34(9): 3136-3146, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38179961

RESUMEN

This study explores the association between phthalates and total vitamin D levels and the link between phthalates exposure and subclinical inflammation using monocyte percentage to high-density lipoprotein cholesterol ratio (MHR), utilizing three National Health and Nutrition Examination Survey (NHANES) survey cycles 2013-2018. This study is cross-sectional, utilizing one-time urine samples from randomly selected NHANES participants to assess phthalate metabolites. An inverse association between vitamin D and all Di(2-ethylhexyl) phthalate (DEHP) metabolites was found. The molar sum of DEHP metabolites was inversely associated with vitamin D (ß -2.329; 95% CI -3.937,-0.720). An inverse association was observed between monocarboxynonyl phthalate and vitamin D (ß -0.0278; 95% CI -0.0527,-0.00298). A similar relationship was found between monocarboxyoctyl phthalate and vitamin D (ß -0.0160; 95% CI -0.0242,-0.00775). There was no association between phthalate metabolites and MHR. Stratified analysis showed that the association between phthalate metabolites and MHR may vary according to vitamin D status.


Asunto(s)
Inflamación , Encuestas Nutricionales , Ácidos Ftálicos , Vitamina D , Humanos , Ácidos Ftálicos/orina , Vitamina D/sangre , Adulto , Masculino , Femenino , Estudios Transversales , Inflamación/inducido químicamente , Inflamación/sangre , Persona de Mediana Edad , Adulto Joven , Contaminantes Ambientales/orina , Contaminantes Ambientales/sangre , Exposición a Riesgos Ambientales , Estados Unidos/epidemiología , Anciano , Adolescente
3.
J Fluoresc ; 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37665513

RESUMEN

Interaction of diclofenac and indomethacin with lysozyme was studied using several spectroscopic and molecular docking methods. Difference UV-visible spectra showed that the absorption profile of lysozyme changed when both diclofenac and indomethacin were mixed with the former. The sequential addition of both drugs to the lysozyme solution caused the decrease of the intrinsic fluorescence of the latter, however, when the data were corrected for inner filter effect, an enhancement in the fluorescence of lysozyme was detected. Accordingly, the fluorescence enhancement data were analyzed using Benesi-Hildebrand equation. Both, diclofenac and indomethacin showed good interaction with lysozyme, although, the association constants of indomethacin were nearly two-fold higher as compared to that of diclofenac. The binding was slightly more spontaneous in case of indomethacin and the major forces involved in the binding of both drugs with lysozyme were hydrogen bonding and hydrophobic interactions. Secondary structural analysis revealed that both drugs partially unfolded lysozyme. Results obtained through molecular docking were also in good agreement with the experimental outcomes. Both, diclofenac and indomethacin, are bounded at the same site inside lysozyme which is located in the big hydrophobic cavity of the protein.

4.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37834259

RESUMEN

The coexistence of ceftazidime, which is a popular third-generation of cephalosporin antibiotic, with ubiquitous paracetamol or acetaminophen, is very likely because the latter is given to the patients to reduce fever due to bacterial infection along with an antibiotic such as the former. Therefore, in this study, we investigated the detailed binding of ceftazidime with plasma protein, human serum albumin (HSA), in the absence and presence of paracetamol using spectroscopic techniques such as fluorescence, UV-visible, and circular dichroism, along with in silico methods such as molecular docking, molecular dynamics simulations, and MM/PBSA-based binding free energy analysis. The basic idea of the interaction was attained by using UV-visible spectroscopy. Further, fluorescence spectroscopy revealed that there was a fair interaction between ceftazidime and HSA, and the mechanism of the quenching was a dynamic one, i.e., the quenching constant increased with increasing temperature. The interaction was, primarily, reinforced by hydrophobic forces, which resulted in the partial unfolding of the protein. Low concentrations of paracetamol were ineffective in affecting the binding of ceftazidime with has; although, a decrease in the quenching and binding constants was observed in the presence of high concentrations of the former. Competitive binding site experiments using warfarin and ibuprofen as site markers revealed that ceftazidime neither binds at drug site 1 or at drug site 2, articulating another binding site, which was confirmed by molecular docking simulations.


Asunto(s)
Acetaminofén , Ceftazidima , Humanos , Ceftazidima/farmacología , Simulación del Acoplamiento Molecular , Unión Proteica , Acetaminofén/farmacología , Termodinámica , Antibacterianos/farmacología , Antibacterianos/química , Sitios de Unión , Albúmina Sérica Humana/química , Espectrometría de Fluorescencia , Dicroismo Circular , Antiinflamatorios no Esteroideos
5.
Molecules ; 28(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37049745

RESUMEN

The interaction of indomethacin with human serum albumin (HSA) has been studied here considering the primary and secondary binding sites. The Stern-Volmer plots were linear in the lower concentration range of indomethacin while a downward curvature was observed in the higher concentration range, suggesting the presence of more than one binding site for indomethacin inside HSA due to which the microenvironment of the fluorophore changed slightly and some of its fraction was not accessible to the quencher. The Stern-Volmer quenching constants (KSV) for the primary and secondary sites were calculated from the two linear portions of the Stern-Volmer plots. There was around a two-fold decrease in the quenching constants for the low-affinity site as compared to the primary binding site. The interaction takes place via a static quenching mechanism and the KSV decreases at both primary and secondary sites upon increasing the temperature. The binding constants were also evaluated, which show strong binding at the primary site and fair binding at the secondary site. The binding was thermodynamically favorable with the liberation of heat and the ordering of the system. In principle, hydrogen bonding and Van der Waals forces were involved in the binding at the primary site while the low-affinity site interacted through hydrophobic forces only. The competitive binding was also evaluated using warfarin, ibuprofen, hemin, and a warfarin + hemin combination as site markers. The binding profile remained unchanged in the presence of ibuprofen, whereas it decreased in the presence of both warfarin and hemin with a straight line in the Stern-Volmer plots. The reduction in the binding was at a maximum when both warfarin and hemin were present simultaneously with the downward curvature in the Stern-Volmer plots at higher concentrations of indomethacin. The secondary structure of HSA also changes slightly in the presence of higher concentrations of indomethacin. Molecular dynamics simulations were performed at the primary and secondary binding sites of HSA which are drug site 1 (located in the subdomain IIA of the protein) and the hemin binding site (located in subdomain IB), respectively. From the results obtained from molecular docking and MD simulation, the indomethacin molecule showed more binding affinity towards drug site 1 followed by the other two sites.


Asunto(s)
Indometacina , Albúmina Sérica Humana , Humanos , Albúmina Sérica Humana/química , Simulación del Acoplamiento Molecular , Unión Proteica , Ibuprofeno , Warfarina , Hemina/metabolismo , Sitios de Unión , Termodinámica , Espectrometría de Fluorescencia , Dicroismo Circular
6.
J Environ Manage ; 316: 115194, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35537267

RESUMEN

The oil spill represents one of the most important pollution sources for marine environments, that occurs due to tanker collisions, ship accidents, and platforms. Several techniques are used for treating oil spill disasters including chemical, physical, and biochemical. The use of chemicals, magnetite nanomaterials (MNMs) in particular, is one of the most applied techniques used for oil spill remediation due to their low cost, fast remediation, and reusability. This work aims to synthesize and use new ionic liquids (ILs) for the modification of MNMs surfaces to enhance their performance for crude oil uptake. For that, octadecylamine (OA) was reacted with epichlorohydrin (EH), followed by reaction with either diethylenetriamine (DT), or tetraethylenepentamine (TP) to obtain corresponding amines, OADT, and OATP, respectively. The produced amines were quaternized using acetic acid (AA) forming corresponding ILs, OADT-IL, and OATP-IL. The obtained ILs, OADT-IL, and OATP-IL were applied for modification of magnetite nanomaterials (MNMs) surface to obtain the surface-modified MNMs, DT-MNMs, and TP-MNMs, respectively. The surface-modified MNMs were characterized using different techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and contact angle. The efficacy of DT-MNMs, and TP-MNMs for heavy crude oil uptake (EMU) was evaluated. Further, the factors affecting on the crude oil uptake including MNMs: heavy crude oil ratio, and contact time were also evaluated. The data exhibited that, the EMU relatively declined as the ratio of DT-MNMs, and TP-MNMs decreased. Even at low MNMs:crude oil ratio (1:50), DT-MNMs, and TP-MNMs displayed EMU 87%, and 90%, respectively, which means 1 g of either DT-MNMs, or TP-MNMs can uptake 45 g, or 43.5 g, respectively. These values are high as compared with other studies that reported the use of MNMs for oil spill cleanup. Furthermore, the data indicated that the EMU increased as the contact time increased, and reached maximum EMU of 98% for both MNMs samples after 10 min.


Asunto(s)
Líquidos Iónicos , Nanoestructuras , Transportadores de Anión Orgánico , Contaminación por Petróleo , Petróleo , Aminas , Óxido Ferrosoférrico , Contaminación por Petróleo/análisis
7.
Molecules ; 27(5)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35268736

RESUMEN

The interaction of common anticancer drug gemcitabine with human serum albumin (HSA) has been studied in detail. The effect of an omnipresent nonsteroidal anti-inflammatory drug ibuprofen was also seen on the binding of HSA and gemcitabine. A slight hyperchromic shift in the difference UV-visible absorption spectra of HSA on the addition of gemcitabine gave a primary idea of the possible complex formation between them. The inner filter effect, which happens due to the significant absorbance of the ligand at the excitation and/or emission wavelengths, played an important role in the observed fluorescence quenching of HSA by gemcitabine that can be understood by comparing the observed and corrected fluorescence intensities obtained at λex = 280 nm and 295 nm. Gemcitabine showed weak interaction with HSA, which took place via a dynamic quenching mechanism with 1:1 cooperative binding between them. Secondary structural analysis, based on circular dichroism (CD) spectroscopy, showed that low concentrations of gemcitabine did not affect the native structure of protein; however, higher concentrations affected it slightly with partial unfolding. For understanding the binding site of gemcitabine within HSA, both experimental (using site markers, warfarin and ibuprofen) as well as computational methods were employed, which revealed that the gemcitabine binding site is located between the interface of subdomain IIA and IIB within the close proximity of the warfarin site (drug site 1). The effect of ibuprofen on the binding was further elaborated because of the possibility of its coexistence with gemcitabine in the prescription given to the cancer patients, and it was noticed that, ibuprofen, even present in high amounts, did not affect the binding efficacy of gemcitabine with HSA. DFT analyses of various conformers of gemcitabine obtained from its docking with various structures of HSA (free and bounded with site markers), show that the stability of the gemcitabine molecule increased slightly after binding with ibuprofen-complexed HSA. Both experimental as well as computational results were in good agreement with each other.


Asunto(s)
Ibuprofeno
8.
Molecules ; 27(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35056754

RESUMEN

In this work, new crosslinked pyridinium poly ionic liquid and its magnetite hybrid structured composite were prepared and applied to remove the toxic dye Coomassie Brilliant Blue (CBB-R250) from aqueous solutions. In this respect, vinyl pyridine, maleic anhydride, and dibromo nonane were used to prepare crosslinked quaternized vinyl pyridinium/maleic anhydride ionic liquid (CQVP-MA). Furthermore, a linear copolymer was prepared by the reaction of vinyl pyridine with bromo nonane followed by its copolymerization with maleic anhydride in order to use it as a capping agent for magnetite nanoparticles. The monodisperse MNPs were incorporated into the crosslinked PIL (CQVP-MA) by ultrasonication to prepare CQVP-MA/Fe3O4 composite to facilitate its recovery using an external magnetic field and enhance its adsorption capacity. The chemical structures, thermal stabilities, zeta potential, particle size, EDS, and SEM of the prepared CQVP-MA and CQVP-MA/Fe3O4 were investigated. Adsorption kinetics, isotherms, and mechanisms of CB-R250 elimination from aqueous solutions using CQVP-MA and CQVP-MA/Fe3O4 were also studied, and the results revealed that the pseudo second-order kinetic model and the Langmuir isotherm model were the most suitable to describe the CBB adsorption from an aqueous solution. The adsorption capacities of CQVP-MA and CQVP-MA/Fe3O4 were found to be 1040 and 1198, respectively, which are more than those for previously reported material in the literature with reasonable stability for five cycles.

9.
Molecules ; 27(10)2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35630715

RESUMEN

This work aimed to use abietic acid (AA), as a widely available natural product, as a precursor for the synthesis of two new amphiphilic ionic liquids (AILs) and apply them as effective demulsifiers for water-in-crude oil (W/O) emulsions. AA was esterified using tetraethylene glycol (TEG) in the presence of p-toluene sulfonic acid (PTSA) as a catalyst obtaining the corresponding ester (AATG). AATG was reacted with 1-vinylimidazole (VIM) throughout the Diels-Alder reaction, forming the corresponding adduct (ATI). Following this, ATI was quaternized using alkyl iodides, ethyl iodide (EI), and hexyl iodide (HI) to obtain the corresponding AILs, ATEI-IL, and ATHI-IL, respectively. The chemical structure, surface activity, thermal stability, and relative solubility number (RSN) were investigated using different techniques. The efficiency of ATEI-IL and ATHI-IL to demulsify W/O emulsions in different crude oil: brine volumetric ratios were evaluated. ATEI-IL and ATHI-IL achieved promising results as demulsifiers. Their demulsification efficiency increased as the brine ratios decreased where their efficiency reached 100% at the crude oil: brine ratio (90:10), even at low concentrations.


Asunto(s)
Líquidos Iónicos , Petróleo , Emulsiones/química , Yoduros , Líquidos Iónicos/química , Petróleo/análisis , Agua/química
10.
Osteoporos Int ; 32(4): 681-688, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32935168

RESUMEN

We investigated the association of objectively ascertained sibling fracture history with major osteoporotic fracture (hip, forearm, humerus, or clinical spine) risk in a population-based cohort using administrative databases. Sibling fracture history is associated with increased major osteoporotic fracture risk, which has implications for fracture risk prediction. INTRODUCTION: We aimed to determine whether objectively ascertained sibling fracture history is associated with major osteoporotic fracture (MOF; hip, forearm, humerus, or clinical spine) risk. METHODS: This retrospective cohort study used administrative databases from the province of Manitoba, Canada, which has a universal healthcare system. The cohort included men and women 40+ years between 1997 and 2015 with linkage to at least one sibling. The exposure was sibling MOF diagnosis occurring after age 40 years and prior to the outcome. The outcome was incident MOF identified in hospital and physician records using established case definitions. A multivariable Cox proportional hazards regression model was used to estimate the risk of MOF after adjustment for known fracture risk factors. RESULTS: The cohort included 217,527 individuals; 91.9% were linked to full siblings (siblings having the same father and mother) and 49.0% were females. By the end of the study period, 6255 (2.9%) of the siblings had a MOF. During a median follow-up of 11 years (IQR 5-15), 5235 (2.4%) incident MOF were identified in the study cohort, including 234 hip fractures. Sibling MOF history was associated with an increased risk of MOF (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.44-1.92). The risk was elevated in both men (HR 1.57, 95% CI 1.24-1.98) and women (HR 1.74, 95% CI 1.45-2.08). The highest risk was associated with a sibling diagnosis of forearm fracture (HR 1.81, 95% CI 1.53-2.15). CONCLUSION: Sibling fracture history is associated with increased MOF risk and should be considered as a candidate risk factor for improving fracture risk prediction.


Asunto(s)
Fracturas de Cadera , Fracturas Osteoporóticas , Adulto , Densidad Ósea , Canadá , Estudios de Cohortes , Femenino , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Humanos , Masculino , Manitoba/epidemiología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Hermanos
11.
Artif Organs ; 45(12): 1501-1512, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34309044

RESUMEN

The primary role of bone tissue engineering is to reconcile the damaged bones and facilitate the speedy recovery of the injured bones. However, some of the investigated metallic implants suffer from stress-shielding, palpability, biocompatibility, etc. Consequently, the biodegradable scaffolds fabricated from polymers have gathered much attention from researchers and thus helped the tissue engineering sector by providing many alternative materials whose functionality is similar to that of natural bones. Herein, we present the fabrication and testing of a novel composite, magnesium (Mg)-doped hydroxyapatite (HAp) glazed onto polylactic acid (PLA) scaffolds where polyvinyl alcohol (PVA) used as a binder. For the composite formation, Creality Ender-3 pro High Precision 3D Printer with Shape tool 3D Technology on an FSD machine operated by Catia design software was employed. The composite has been characterized for the crystallinity (XRD), surface functionality (FTIR), morphology (FESEM), biocompatibility (hemolytic and protein absorption), and mechanical properties (stress-strain and maximum compressive strength). The powder XRD analysis confirmed the semicrystalline nature and intact structure of HAp even after doping with Mg, while FTIR studies for the successful formation of Mg-HAp/PVA@PLA composite. The FESEM provided analysis indicated for the 3D porous architecture and well-defined morphology to efficiently transport the nutrients, and the biocompatibility studies are supporting that the composite for blood compatible with the surface being suitable enough for the protein absorption. Finally, the composite's antibacterial activity (against Staphylococcus aureus and Escherichia coli) and the test of mechanical properties supported for the enhanced inhibition of active growth of microorganisms and maximum compressive strength, respectively. Based on the research outcomes of biocompatibility, antibacterial activity, and mechanical resistance, the fabricated Mg-HAp/PVA@PLA composite suits well as a promising biomaterial platform for orthopedic applications by functioning towards the open reduction internal fixation of bone fractures and internal repairs.


Asunto(s)
Huesos , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido , Durapatita/química , Escherichia coli/efectos de los fármacos , Hemólisis , Humanos , Magnesio/química , Ensayo de Materiales , Impresión Tridimensional , Staphylococcus aureus/efectos de los fármacos
12.
Molecules ; 26(20)2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34684699

RESUMEN

In the last few decades, there has been an increasing trend for the usage of natural products and their derivatives as green and renewable oil-filed chemicals. Use of these compounds or their derivatives contributes to reducing the use of traditional chemicals, and enhances green chemistry principles. Curcumin (CRC) is one of the most popular natural products and is widely available. The green character, antioxidant action, and low cost of CRC prompt its use in several applications. In the present study, Curcumin was used to synthesize two new amphiphilic ionic liquids (AILs) by reacting with 1,3-propanesultone or bromoacetic acid to produce corresponding sulfonic and carboxylic acids, CRC-PS and CRC-BA, respectively. Following this, the formed CRC-PS and CRC-BA were allowed to react with 12-(2-hydroxyethyl)-15-(4-nonylphenoxy)-3,6,9-trioxa-12-azapentadecane-1,14-diol (HNTA) to form corresponding AILs, GCP-IL and GRB-IL, respectively. The chemical structures, surface tension, interfacial tension, and relative solubility number (RSN) of the synthesized AILs were investigated. The efficiency of GCP-IL and GRB-IL to demulsify water in heavy crude oil (W/O) emulsions was also investigated, where we observed that both GCP-IL and GRB-IL served as high-efficiency demulsifiers and the efficiency increased with a decreased ratio of water in W/O emulsion. Moreover, the data showed an increased efficiency of these AILs with an increased concentration. Among the two AILs, under testing conditions, GCP-IL exhibited a higher efficiency, shorter demulsification time, and cleaner demulsified water.


Asunto(s)
Curcumina/análogos & derivados , Emulsionantes/síntesis química , Emulsiones/química , Líquidos Iónicos/química , Aceites/química , Purificación del Agua/métodos , Curcumina/síntesis química , Interacciones Hidrofóbicas e Hidrofílicas , Tensoactivos
13.
Molecules ; 26(21)2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34771048

RESUMEN

Lysozyme is often used as a model protein to study interaction with drug molecules and to understand biological processes which help in illuminating the therapeutic effectiveness of the drug. In the present work, in vitro interaction studies of 1-{(2-hydroxyethyl)amino}-2-amino-1,2-dideoxy-d-glucose triphenyl tin (IV) (GATPT) complex with lysozyme were carried out by employing various biophysical methods such as absorption, fluorescence, and circular dichroism (CD) spectroscopies. The experimental results revealed efficient binding affinity of GATPT with lysozyme with intrinsic binding (Kb) and binding constant (K) values in the order of 105 M-1. The number of binding sites and thermodynamic parameters ΔG, ΔH, and ΔS at four different temperatures were also calculated and the interaction of GATPT with lysozyme was found to be enthalpy and entropy driven. The CD spectra revealed alterations in the population of α-helical content within the secondary structure of lysozyme in presence of GATPT complex. The morphological analysis of the complex with lysozyme and lysozyme-DNA condensates was carried out by employing confocal and SEM studies. Furthermore, the molecular docking studies confirmed the interaction of GATPT within the larger hydrophobic pocket of the lysozyme via several non-covalent interactions.


Asunto(s)
Aminoglicósidos/química , Proteínas Portadoras/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Compuestos Organometálicos/química , Compuestos Orgánicos de Estaño/química , Análisis Espectral , Sitios de Unión , ADN/química , Cinética , Conformación Molecular , Muramidasa/química , Unión Proteica , Termodinámica
14.
Molecules ; 26(3)2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33499387

RESUMEN

Two novel amphiphilic polyethylene amine terephthalate have been prepared via the glycolsis of polyethylene terephthalate (PET). The product, bis (2-hydroxyethyl terephthalate) (BHET), was converted to the corresponding dialkyl halide, bis(2-chloroethyl) terephthalate (BCET), using thionyl chloride (TC). This dialkyl compound was used for alkylation of dodecyl amine (DOA) and tetraethylenepentamine (TEPA) or pentaethylenehexamine (PEHA) to form the corresponding polyethylene amine terephthalate, i.e., DOAT and DOAP, respectively. Their chemical structure, surface tension, interfacial tension (IFT), and dynamic light scattering (DLS) were determined using different techniques. The efficiency of the prepared polyethylene amine terephthalate to demulsify water in heavy crude (W/O) emulsions was also determined and found to increase as their concentrations increased. Moreover, DOAT showed faster and higher efficiency, and cleaner separation than DOAP.


Asunto(s)
Petróleo/análisis , Tereftalatos Polietilenos/química , Aminas/síntesis química , Aminas/química , Dispersión Dinámica de Luz , Emulsiones/química , Espectroscopía de Resonancia Magnética , Micelas , Estructura Molecular , Tereftalatos Polietilenos/síntesis química , Eliminación de Residuos/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Tensión Superficial , Tensoactivos/síntesis química , Tensoactivos/química , Aguas Residuales/química
15.
J Contemp Dent Pract ; 22(1): 51-55, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34002709

RESUMEN

AIM: To investigate risk factors associated with halitosis in children using OralChroma™. MATERIALS AND METHODS: Sixty-seven children between the ages of 3 and 8 who attended a pre-general anesthesia assessment at the Dental University Hospital at King Saud University, Riyadh, Saudi Arabia, were enrolled in this study after satisfying the inclusion criteria. Demographic data, medical history, and oral hygiene practices were obtained by a standardized questionnaire completed by the parents of each child. Clinical dental examination was conducted to record the following: caries index (dmft/DMFT), simplified debris index (DI-S), modified gingival index (MGI), and Winkel tongue coating index (WTCI). Clinical halitosis was assessed using the OralChroma™ device that measures the concentration of volatile sulfur compounds (VSCs) including hydrogen sulfide (H2S), methyl mercaptan (CH3SH), and dimethyl sulfide (CH3SCH3). Statistics were completed using Spearman's correlation coefficient and Mann-Whitney U-test to assess the association with the VSC scores with continuous and binary variables, respectively. Then, multivariate linear regression analysis was performed to detect the degree of association. RESULTS: High VSC measures were detected in 58 children (87%). The dmft/DMFT was significantly associated with H2S level (ß = 26.84, p = 0.034) and CH3SH level (ß = 19.96, p = 0.016) after controlling possible confounders. There was no significant association of DI-S, MGI, and WTCI with the VSC measures. CONCLUSION: The result suggested that dmft/DMFT score (children's caries experience) is associated significantly with high levels of H2S and CH3SH in the sample studied. CLINICAL SIGNIFICANCE: Caries experience in children is a significant risk factor for halitosis and should be considered during the management of halitosis.


Asunto(s)
Halitosis , Niño , Preescolar , Estudios Transversales , Halitosis/epidemiología , Halitosis/etiología , Humanos , Factores de Riesgo , Arabia Saudita/epidemiología , Compuestos de Azufre/análisis , Lengua
16.
Molecules ; 25(11)2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32526838

RESUMEN

Early diagnosis of bone metastases is crucial to prevent skeletal-related events, and for that, the non-invasive techniques to diagnose bone metastases that make use of image-guided radiopharmaceuticals are being employed as an alternative to traditional biopsies. Hence, in the present work, we tested the efficacy of a gallium-68 (68Ga)-based compound as a radiopharmaceutical agent towards the bone imaging in positron emitting tomography (PET). For that, we prepared, thoroughly characterized, and radiolabeled [68Ga]Ga-NODAGA-pamidronic acid radiopharmaceutical, a 68Ga precursor for PET bone cancer imaging applications. The preparation of NODAGA-pamidronic acid was performed via the N-Hydroxysuccinimide (NHS) ester strategy and was characterized using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (MSn). The unreacted NODAGA chelator was separated using the ion-suppression reverse phase-high performance liquid chromatography (RP-HPLC) method, and the freeze-dried NODAGA-pamidronic acid was radiolabeled with 68Ga. The radiolabeling condition was found to be most optimum at a pH ranging from 4 to 4.5 and a temperature of above 60 °C. From previous work, we found that the pamidronic acid itself has a good bone binding affinity. Moreover, from the analysis of the results, the ionic structure of radiolabeled [68Ga]Ga-NODAGA-pamidronic acid has the ability to improve the blood clearance and may exert good renal excretion, enhance the bone-to-background ratio, and consequently the final image quality. This was reflected by both the in vitro bone binding assay and in vivo animal biodistribution presented in this research.


Asunto(s)
Acetatos/farmacocinética , Huesos/diagnóstico por imagen , Huesos/metabolismo , Radioisótopos de Galio/farmacocinética , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Pamidronato/farmacocinética , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Acetatos/química , Animales , Cromatografía Líquida de Alta Presión , Radioisótopos de Galio/química , Compuestos Heterocíclicos con 1 Anillo/química , Masculino , Espectrometría de Masas , Pamidronato/química , Radiofármacos/química , Ratas , Ratas Sprague-Dawley , Distribución Tisular
17.
J Nanosci Nanotechnol ; 19(5): 2590-2598, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30501755

RESUMEN

Cobalt oxide nanorods were successfully synthesized by a hot plate combustion method using the plant extract of Vitis vinifera. The plant extract as an alternative to toxic chemicals can be used generally as reducing and capping agents. The obtained nanorods were characterized by XRD, FT-IR, Raman, TEM, SAED, EDX, DRS, PL and VSM techniques for the structural, morphological, optical and magnetic properties. The XRD, FT-IR, Raman, EDX analysis confirmed the high purity of the sample. The TEM and SAED results showed the rod shape morphology of the sample. DRS and PL showed the band gap energy and emission at visible region. VSM showed the antiferromagnetic nature of the sample. The photocatalytic activities of the as-prepared cobalt oxide nanorods were investigated for the degradation of textile dying waste water. As per the standards of Indian pollution control board for industrial waste water let out into river bodies, the degradation reactions of waste water was found to be 250 mg/L at 150 min. Also, the same catalyst is used for the reduction of 4-nitrophenol and 4-nitroaniline using sodium borohydride as a reducing agent and it exhibits excellent reduction reaction, because of the high active surface sites. The time taken for the reduction reaction was 300 sec and 210 sec for 4-nitrophenol and 4-nitroaniline respectively. Also, the antibacterial activities towards the bacterial strains were studied and reported.


Asunto(s)
Antibacterianos , Nanotubos , Antibacterianos/farmacología , Catálisis , Cobalto , Óxidos , Espectroscopía Infrarroja por Transformada de Fourier
18.
Dis Esophagus ; 32(6)2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30828713

RESUMEN

The aim of this study is to investigate management and outcome in esophageal atresia (EA) and to identify early predictive factors of morbidity and mortality in a developing country. Charts of neonates with repaired EA from 2007 to 2016 were reviewed. Patients' characteristics, operative details, and postoperative outcomes were collected. Statistical analyses were performed to identify predictors of complicated evolution. Forty-two cases were collected. There were 14 girls and 28 boys. Only one patient had antenatal diagnosis (2.3%). The mean gestational age was 38 weeks. Nine patients (21.4%) weighed less than 2.5 kg. Seventeen (40.4%) patients had associated malformations most commonly cardiac (9/17). Thirteen patients had delayed diagnosis (30.9%). Thirty-nine (92.8%) patients underwent primary esophageal anastomosis. Overall survival was 76.2%. Nineteen patients (57% of survivals) had complicated evolution before the age of one year and 15 patients (46.8% of survivals) developed complications after the age of one year. Perinatal variables associated with mortality were prematurity (p = 0.004, OR = 5.4, IC95% = [1.13-25.80]), low birth weight (p = 0.023, OR = 7, IC95% = [1.38-35.47]), cardiac malformations (p = 0.006, OR = 10.5, IC95% = [2.03-54.27]) and delayed diagnosis (p = 0.005, OR = 10.11, IC95% = [2.005-50.980]). Variables associated with short-term and middle-term complications were duration of intubation (p = 0.019, OR = 0.118, IC95% = [0.019-0.713]) and the presence of short-term complications (p = 0.016, OR = 7.33, IC95% = [1.467-36.664]) respectively. These factors may be used to identify patients who will benefit from more intensive follow-up program.


Asunto(s)
Países en Desarrollo/estadística & datos numéricos , Atresia Esofágica/mortalidad , Atresia Esofágica/cirugía , Fístula Esofágica/etiología , Esófago/cirugía , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/etiología , Atresia Esofágica/diagnóstico , Estenosis Esofágica/etiología , Femenino , Humanos , Lactante , Recién Nacido , Intubación Intratraqueal/efectos adversos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Túnez/epidemiología
19.
Ophthalmic Plast Reconstr Surg ; 35(6): e134-e136, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31593047

RESUMEN

Orbital subperiosteal hemorrhages are usually due to trauma. However, nontraumatic subperiosteal hemorrhages have also been rarely reported. Here, the authors present a 13-year-old boy with Bernard-Soulier syndrome who presented with right orbital subperiosteal hemorrhage causing optic neuropathy which was surgically drained with full visual recovery.The authors describe a case of rare coagulopathy (Bernard-Soulier syndrome) and pansinusitis presenting with nontraumatic subperiosteal hemorrhage.


Asunto(s)
Síndrome de Bernard-Soulier/complicaciones , Hemorragia Retrobulbar/etiología , Sinusitis/complicaciones , Adolescente , Humanos , Masculino , Enfermedades del Nervio Óptico/etiología
20.
Mikrochim Acta ; 186(7): 420, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31187268

RESUMEN

A sensitive electrochemical (voltammetric; DPV) sensor has been developed for the determination of coccidiostat drug (roxarsone) based on the use of an SPCE (screen-printed carbon electrode) modified with tungsten disulfide nanosheets (WS2 NSs). The electrochemical detection of roxarsone on the WS2-modified SPCE was examined by electrochemical strategies. XPS, XRD, Raman, SEM, TEM, EDS and EIS were used to characterize the nanosheets. The effects of scan rate, pH values (phosphate buffer) and buffer concentration were optimized. A selective roxarsone sensor was developed that works best at -0.64 V (vs. Ag/AgCl) and performs much better than the bare SPCE. Features include (a) a wider linear range (0.05 to 490 µM), (b) a nanomolar detection limit (0.03 µM) and (c) high sensitivity (29 µA·µM-1·cm-2). The modified SPCEs have been successfully applied to the determination of roxarsone in spiked meat samples where they gave high accuracy and good recoveries. Graphical abstract Synthesis of WS2 nanosheets and electrochemical detection of roxarsone.


Asunto(s)
Coccidiostáticos/análisis , Nanoestructuras/química , Roxarsona/análisis , Sulfuros/química , Compuestos de Tungsteno/química , Catálisis , Coccidiostáticos/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Contaminación de Alimentos/análisis , Límite de Detección , Carne/análisis , Oxidación-Reducción , Reproducibilidad de los Resultados , Roxarsona/química
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