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1.
Bioresour Technol ; 403: 130861, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38768663

RESUMEN

Developing an optimized and targeted design approach for metal-modified biochar based on water quality conditions and management is achievable through machine learning. This study leveraged machine learning to analyze experimental data on phosphate adsorption by metal-modified biochar from literature published in Web of Science. Using six machine learning models, the phosphate adsorption capacity of biochar and residual phosphate concentration were predicted. After hyperparameter optimization, the gradient boosting model exhibited superior training performance (R2 > 0.96). Metal load quantity, solid-liquid ratio, and pH were key factors influencing adsorption performance. Optimal preparation parameters indicated that Mg-modified biochar achieved the highest adsorption capacity (387-396 mg/g), while La-modified biochar displayed the lowest residual phosphate concentration (0 mg/L). The results of verification experiments based on optimized process parameters closely aligned with model predictions. This study introduces a new machine learning-based approach for tailoring biochar preparation processes considering different water quality management objectives.


Asunto(s)
Carbón Orgánico , Aprendizaje Automático , Fósforo , Purificación del Agua , Calidad del Agua , Carbón Orgánico/química , Adsorción , Purificación del Agua/métodos , Metales/química , Contaminantes Químicos del Agua , Concentración de Iones de Hidrógeno
2.
J Environ Manage ; 351: 119837, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154225

RESUMEN

Phosphate concentrations in eutrophic surface waters are usually low, and efficient removal of low concentration phosphate remains a challenge. In this study, Ca-doped LaMnO3 synthesized at doping ratios, designated as CaxLa1-xMnO3 (x = 0, 0.2, 0.4, 0.7), were compared. It was found that, the adsorption capacity of Ca0.4La0.6MnO3 material reached 63.01 mg/g at pH = 5, increased by 63.6% over the undoped LaMnO3 perovskite. For long-term adsorption, Ca0.4La0.6MnO3 could constantly adsorb phosphate to avoid phosphate accumulation (<0.05 mg/L). This proves that Ca0.4La0.6MnO3 has the ability to control dynamic water eutrophication. Characterization and density functional theory results confirmed that CaxLa1-xMnO3 can increase the content of mesopores and oxygen vacancies, providing additional active sites. This reduces the adsorption energy of the La site, promotes electron transfer, and increases its affinity. It provides a new method for removing low-concentration phosphates.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Fosfatos/química , Agua , Concentración de Iones de Hidrógeno , Cinética
3.
Chemosphere ; 336: 139251, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37331662

RESUMEN

Metal ions or metal (hydrogen) oxides are widely used as active sites in the construction of phosphate-adsorbing materials in water, but the removal of soluble organophosphorus from water remains technically difficult. Herein, synchronous organophosphorus oxidation and adsorption removal were achieved using electrochemically coupled metal-hydroxide nanomaterials. La-Ca/Fe-layered double hydroxide (LDH) composites prepared using the impregnation method removed both phytic acid (inositol hexaphosphate, IHP) and hydroxy ethylidene diphosphonic acid (HEDP) acid under an applied electric field. The solution properties and electrical parameters were optimized under the following conditions: organophosphorus solution pH = 7.0, organophosphorus concentration = 100 mg L-1, material dosage = 0.1 g, voltage = 15 V, and plate spacing = 0.3 cm. The electrochemically coupled LDH accelerates the removal of organophosphorus. The IHP and HEDP removal rates were 74.9% and 47%, respectively in only 20 min, 50% and 30% higher, respectively, than that of La-Ca/Fe-LDH alone. The removal rate in actual wastewater reached 98% in only 5 min. Meanwhile, the good magnetic properties of electrochemically coupled LDH allow easy separation. The LDH adsorbent was characterized using scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analysis. It exhibits a stable structure under electric field conditions, and its adsorption mechanism mainly includes ion exchange, electrostatic attraction, and ligand exchange. This new approach for enhancing the adsorption capacity of LDH has broad application prospects in organophosphorus removal from water.


Asunto(s)
Compuestos Organofosforados , Contaminantes Químicos del Agua , Adsorción , Ácido Etidrónico , Concentración de Iones de Hidrógeno , Hidróxidos/química , Cinética , Aguas Residuales , Agua , Contaminantes Químicos del Agua/química , Compuestos Organofosforados/química
4.
Environ Sci Pollut Res Int ; 30(25): 66638-66650, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37101212

RESUMEN

La-based adsorbents are widely used for controlling phosphate concentration in water bodies. In order to explore the effect of different B-site metals regulating La-based perovskites on phosphate adsorption, three La-based perovskites (LaBO3, B = Fe, Al, and Mn) were prepared using the citric acid sol-gel method. Adsorption experiments showed that LaFeO3 exhibited the highest adsorption capacity for phosphate, which was 2.7 and 5 times higher than those of LaAlO3 and LaMnO3, respectively. The characterization results demonstrated that LaFeO3 has dispersed particles exhibiting larger pore size and more pores than LaAlO3 and LaMnO3. Spectroscopy analysis and density functional theory calculation results showed that different B-positions cause a change in the type of perovskite crystals. Among them, the differences between lattice oxygen consumption ratio, zeta potential and adsorption energy are the main reasons for the differences in adsorption capacity. In addition, the adsorption of phosphate by La-based perovskites were well fitted with Langmuir isotherm and pursues the pseudo-second-order kinetic models. The maximum adsorption capacities were 33.51, 12.31 and 6.61 mg/g for LaFeO3, LaAlO3 and LaMnO3, respectively. The adsorption mechanism was mainly based on inner-sphere complexation and electrostatic attraction. This study provides an explanation for the influence of different B sites on phosphate adsorption by perovskite.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Fosfatos/química , Lantano/química , Óxidos , Cinética , Contaminantes Químicos del Agua/química
5.
ACS Appl Mater Interfaces ; 15(13): 16942-16952, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36961428

RESUMEN

La-based metal oxide materials are environmentally friendly and show promise for phosphate adsorption. A series of Al-doped perovskite oxides, such as LaFexAl1-xO3, were prepared using a facile citric acid-assisted sol-gel method. The characterization results demonstrated that with optimized Al doping, there was a significant increase in the specific surface area and increased defect content of perovskite oxide LaFexAl1-xO3. Adsorption experiments showed that the performance of phosphate removal by LaFexAl1-xO3 was largely enhanced due to the improved adsorption capacity, which is maximum eight times higher compared with control perovskites prepared under neutral conditions. The mass transfer rate for adsorption was considerably boosted with phosphate removal within the initial 15 min. Spectroscopy analysis and density functional theory calculation results showed that the process of phosphate removal by the Al-doped perovskite oxides LaFexAl1-xO3 involved electrostatic interactions, an inner-sphere complex, and surface oxygen vacancies, among which the creation of oxygen vacancies caused by the Al doping was the predominant mechanism for reducing the bonding barrier during adsorption and generating adsorption sites. The results enable the development of a green and efficient perovskite adsorbent with a La-based perovskite material for phosphorus removal.

6.
J Antibiot (Tokyo) ; 73(9): 646-649, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32269298

RESUMEN

Hericerin is an isoindolinone meroterpenoid alkaloid isolated from medicinal mushroom Hericium erinaceum with some bioactivities. Herein, a concise total synthesis of hericerin was described, with four steps and 30% overall yield starting from commercially available methyl 3-hydroxy-5-methoxybenzoate and geranyl bromide. A comprehensive effect of hericerin on HepG2 cell line was observed and confirmed by transcriptomic analysis. Furthermore, hericerin was found to be a new PPARγ agonist.


Asunto(s)
Hericium/metabolismo , Lactamas/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Agaricales/metabolismo , Línea Celular Tumoral , Células Hep G2 , Humanos , Lactamas/farmacología , Transcriptoma/efectos de los fármacos
7.
J Antibiot (Tokyo) ; 73(3): 189-193, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31827255

RESUMEN

A new p-terphenyl derivative aspergicandidusin A (1), a new cleistanthane diterpenoid 6-deoxyaspergiloid C (13), and 12 known compounds (2-12, and 14) were isolated from the mold Aspergillus candidus. The structures of the new compounds were elucidated by spectral analysis of NMR and MS data. The absolute configuration of C-1 in 13 was determined via the circular dichroism data of the [Rh2(OCOCF3)4] complex. Compounds 2-8 and 11 showed moderate inhibitory activity against K562 cell lines with the IC50 value in the range from 17.9 to 46.3 µM. Compound 13 exhibited moderate cytotoxicity against HepG2 cells with the IC50 value of 47.7 µM. Compounds 11 and 12 exhibited moderate activity against the growth of S. aureus with MIC value of 6.25 µM, respectively.


Asunto(s)
Aspergillus/metabolismo , Terpenos/metabolismo , Compuestos de Terfenilo/metabolismo , Triticum/microbiología , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Aspergillus/clasificación , Células Hep G2 , Humanos , Células K562 , Modelos Moleculares , Estructura Molecular , Terpenos/química , Terpenos/farmacología , Compuestos de Terfenilo/química , Compuestos de Terfenilo/farmacología
8.
Eur J Med Chem ; 123: 309-316, 2016 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-27484516

RESUMEN

In our previous work, novel 2,4,5-trisubstituted thiazole derivatives (TSTs) were synthesized, and their activities were evaluated against HIV-1 reverse transcriptase. Some interesting results were obtained, which led us to a new discovery regarding these TSTs. In the present study, 21 new 2,4,5-trisubstituted thiazole derivatives were rationally designed and synthesized as HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) in accordance with our previous study. Among the synthesized target compounds, compounds 14, 16, 17, and 19 showed more potent inhibitory activities against HIV-1 with an IC50 value of 0.010 µM. Compounds 4, 9, 10, 11, 13 and 16 were further tested on nine NNRTI-resistant HIV-1 strains, and all of these compounds exhibited inhibitory effects. A molecular docking study was conducted, and the results showed a consistent and stable binding mode for the typical compounds. These results have provided deeper insights and SAR of these types of NNRTIs.


Asunto(s)
Transcriptasa Inversa del VIH/antagonistas & inhibidores , VIH-1/enzimología , Mutación , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología , Tiazoles/química , Tiazoles/farmacología , Diseño de Fármacos , Células HEK293 , Transcriptasa Inversa del VIH/química , Transcriptasa Inversa del VIH/genética , Transcriptasa Inversa del VIH/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Conformación Proteica , Inhibidores de la Transcriptasa Inversa/metabolismo , Relación Estructura-Actividad , Tiazoles/metabolismo
9.
Eur J Med Chem ; 85: 27-42, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-25072874

RESUMEN

Novel 2,4,5-trisubstituted thiazole derivatives (TSTs) were designed and synthesized as HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs). Among the thirty-eight synthesized target compounds, thirty TSTs showed potent inhibition against HIV-1 replication in wild type HIV-1 at submicromolar concentrations (from 0.046 to 9.59 µM). Compounds 21, 23 and 24 were also tested on seven NNRTI-resistant HIV-1 strains, and all exhibited inhibitory effects with fold changes in IC50 ranging from 2.6 to 111, which were better than those of nevirapine (15.6-fold-371-fold). Docking simulations of compound 24 revealed a reasonable mechanism for the binding mode, and three-dimensional quantitative structure activity relationship (3-DQSAR) studies on this novel series of TST further elucidated the structure-activity relationship (SAR). The results suggested the great potential of TSTs as a novel class of NNRTIs with antiviral efficacy and a good resistance profile.


Asunto(s)
Diseño de Fármacos , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Transcriptasa Inversa del VIH/genética , VIH-1/enzimología , Mutación , Tiazoles/química , Tiazoles/farmacología , Farmacorresistencia Viral/efectos de los fármacos , Células HEK293 , Transcriptasa Inversa del VIH/química , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Concentración 50 Inhibidora , Modelos Moleculares , Conformación Proteica , Relación Estructura-Actividad Cuantitativa , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología
10.
Bioorg Med Chem Lett ; 23(21): 5850-4, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24055046

RESUMEN

A series of 2-(6-methylpyridin-2-yl)-1H-imidazoles were synthesized and evaluated for ALK5 inhibitory activity in cell-based luciferase reporter assays. The compound 4-(((1-(benzo[d][1,3]dioxol-5-yl)-2-(6-methylpyridin-2-yl)-1H-imidazol-4-yl)methyl)amino)benzenesulfonamide (27a) exhibited slightly higher inhibition (IC50=0.24µM) than SB431542 (IC50=0.35µM), a well known potent ALK5 inhibitor. The binding mode of 27a generated by flexible docking study shows that it fits well into the site cavity of ALK5 by forming several tight interactions.


Asunto(s)
Imidazoles/química , Imidazoles/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Benzamidas/química , Benzamidas/farmacología , Dioxoles/química , Dioxoles/farmacología , Humanos , Imidazoles/síntesis química , Simulación del Acoplamiento Molecular , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/química , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Relación Estructura-Actividad
11.
Spine J ; 12(10): 902-11, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23098615

RESUMEN

BACKGROUND CONTEXT: Readmissions within 30 days of hospital discharge are undesirable and costly. Little is known about reasons for and predictors of readmissions after elective spine surgery to help plan preventative strategies. PURPOSE: To examine readmissions within 30 days of hospital discharge, reasons for readmission, and predictors of readmission among patients undergoing elective cervical and lumbar spine surgery for degenerative conditions. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Patient sample includes 343,068 Medicare beneficiaries who underwent cervical and lumbar spine surgery for degenerative conditions from 2003 to 2007. OUTCOME MEASURES: Readmissions within 30 days of discharge, excluding readmissions for rehabilitation. METHODS: Patients were identified in Medicare claims data using validated algorithms. Reasons for readmission were classified into clinically meaningful categories using a standardized coding system (Clinical Classification Software). RESULTS: Thirty-day readmissions were 7.9% after cervical surgery and 7.3% after lumbar surgery. There was no dominant reason for readmissions. The most common reasons for readmissions were complications of surgery (26%-33%) and musculoskeletal conditions in the same area of the operation (15%). Significant predictors of readmission for both operations included older age, greater comorbidity, dual eligibility for Medicare/Medicaid, and greater number of fused levels. For cervical spine readmissions, additional risk factors were male sex, a diagnosis of myelopathy, and a posterior or combined anterior/posterior surgical approach; for lumbar spine readmissions, additional risk factors were black race, Middle Atlantic geographic region, fusion surgery, and an anterior surgical approach. Our model explained more than 60% of the variability in readmissions. CONCLUSIONS: Among Medicare beneficiaries, 30-day readmissions after elective spine surgery for degenerative conditions represent a target for improvement. Both patient factors and operative techniques are associated with readmissions. Interventions to minimize readmissions should be specific to surgical site and focus on high-risk subgroups where clinical trials of interventions may be of greatest benefit.


Asunto(s)
Procedimientos Quirúrgicos Electivos , Medicare Part A , Readmisión del Paciente/estadística & datos numéricos , Enfermedades de la Columna Vertebral/cirugía , Anciano , Anciano de 80 o más Años , Vértebras Cervicales/patología , Vértebras Cervicales/cirugía , Procedimientos Quirúrgicos Electivos/efectos adversos , Femenino , Humanos , Vértebras Lumbares/patología , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Factores de Riesgo , Enfermedades de la Columna Vertebral/epidemiología , Estados Unidos/epidemiología
12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2205, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22798867

RESUMEN

In the title compound, C(33)H(38)N(4)O(3), the mean planes of the 9H-xanthene unit and spiro-lactam (nine-atom) core are almost mutually perpendicular at 87.26 (6)°. Intra-molecular N-H⋯O and C-H⋯N inter-actions influence the 4-oxo-pent-2-en-2-yl-amino conformation. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into chains along [001].

13.
Yao Xue Xue Bao ; 47(4): 427-33, 2012 Apr.
Artículo en Chino | MEDLINE | ID: mdl-22799022

RESUMEN

Liver X receptor (LXR), a member of the superfamily of nuclear receptors, plays an important role in the activation of transcription factors involved in cholesterol metabolism, glucose homeostasis inflammation and lipogenesis. It is shown that LXR agnoists have the potentiality to be used as drugs for the prevention and treatment of atherosclerosis, which is its best investigated therapeutic indication. There are many compounds being studied in preclinical evaluation and biological assay. This paper will review briefly the LXR agonists in recent years.


Asunto(s)
Aminas/síntesis química , Bencimidazoles/síntesis química , Receptores Nucleares Huérfanos/agonistas , Quinolinas/síntesis química , Transportadoras de Casetes de Unión a ATP/metabolismo , Aminas/química , Aminas/farmacología , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Bencimidazoles/química , Bencimidazoles/farmacología , Colesterol/análogos & derivados , Colesterol/farmacología , Glucosa/análogos & derivados , Glucosa/farmacología , Humanos , Metabolismo de los Lípidos , Lipogénesis , Receptores X del Hígado , Receptores Nucleares Huérfanos/fisiología , Quinolinas/química , Quinolinas/farmacología , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo
14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): o361, 2011 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-21523040

RESUMEN

In the title compound, C(22)H(23)FN(2)OS, the piperidine ring shows chair confirmation and the two benzene rings make a dihedral angle of 17.0 (6)°. The thia-zole fragment is essentially planar with an r.m.s. deviation of 0.004 (2) Šand a maximum deviation of 0.006 (2) Å.. In the crystal, inter-molecular C-H⋯π inter-actions lead to the formation of a layer structure.

15.
Cancer ; 117(2): 398-405, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20824718

RESUMEN

BACKGROUND: The authors sought to identify socioeconomic (SES) factors associated with adjuvant hormone therapy (HT) use among a contemporary population of older breast cancer survivors. METHODS: Telephone surveys were conducted among women (ages 65-89 years) residing in 4 states (California, Florida, Illinois, and New York) who underwent initial breast cancer surgery in 2003. Demographic, SES, and treatment information was collected. RESULTS: Of 2191 women, 67% received adjuvant HT with either tamoxifen or an aromatase inhibitor (AI); 71% of those women were on an AI. When adjusting for multiple demographic and SES factors, predictors of HT use were better education (high school degree or higher), better informational/emotional support, and younger age (ages 65-79 years). Race/ethnicity, income, and insurance coverage for medication costs were not associated with receiving HT. For those on HT, when adjusting for all other factors, women were more likely to receive an AI if they had insurance coverage for some or all medication costs, if they were wealthier, if they had better informational/emotional support, and if they were younger (ages 65-69 years). CONCLUSIONS: The majority of older women in this population-based cohort received adjuvant HT, and the adoption of AIs was early. The results indicted that providers should be aware that a woman's education level and support system influence her decision to take HT. Given the high cost of AIs, their benefits in postmenopausal women with hormone receptor-positive breast cancer, and the current finding that women with no insurance coverage for medication costs were significantly less likely to receive an AI, we recommend that policymakers address this issue.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Factores Socioeconómicos , Sobrevivientes , Tamoxifeno/uso terapéutico , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Escolaridad , Femenino , Humanos , Apoyo Social
18.
Bioorg Med Chem ; 11(24): 5539-44, 2003 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-14642598

RESUMEN

2-Sulfonylphenyl-3-phenyl-indole derivatives have been reported to be highly potent and selective COX-2 inhibitors previously. In this paper, the regio-isomeric analogues-2-phenyl-3-sulfonylphenyl-indoles were identified as potent and selective COX-2 inhibitors. This work led to the discovery of compounds 4a and 8a possessing higher activity than Celecoxib on cellular assay.


Asunto(s)
Inhibidores de la Ciclooxigenasa/síntesis química , Inhibidores de la Ciclooxigenasa/farmacología , Indoles/síntesis química , Indoles/farmacología , Isoenzimas/antagonistas & inhibidores , Animales , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/clasificación , Indoles/clasificación , Macrófagos Peritoneales/enzimología , Masculino , Proteínas de la Membrana , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Prostaglandina-Endoperóxido Sintasas
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