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1.
Inorg Chem ; 57(14): 8299-8306, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-29952559

RESUMO

The electrochemical reduction of trivalent samarium in a LiCl-KCl eutectic melt produced highly stable divalent samarium, whose electrochemical properties and electronic structure in the molten salt were investigated using cyclic voltammetry, UV-vis absorption spectroscopy, laser-induced emission spectroscopy, and density functional theory (DFT) calculations. Diffusion coefficients of Sm2+ and Sm3+ were electrochemically measured to be 0.92 × 10-5 and 1.10 × 10-5 cm2/s, respectively, and the standard apparent potential of the Sm2+/3+ couple was estimated to be -0.82 V vs Ag|Ag+ at 450 °C. The spectroelectrochemical study demonstrated that the redox behavior of the samarium cations obeys the Nernst equation ( E°' = -0.83 V, n = 1) and the trivalent samarium cation was successfully converted to the divalent cation having characteristic absorption bands at 380 and 530 nm with molar absorptivity values of 1470 and 810 M-1 cm-1, respectively. Density function theory calculations for the divalent samarium complex revealed that the absorption signals originated from the 4f6 to 4f55d1 transitions. Additionally, laser-induced emission measurements for the Sm cations in the LiCl-KCl matrix showed that the Sm3+ ion in the LiCl-KCl melt at 450 °C emitted an orange color of fluorescence, whereas a red colored emission was observed from the Sm2+ ion in the solidified LCl-KCl salt at room temperature.

2.
BMC Complement Altern Med ; 16: 239, 2016 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-27456850

RESUMO

BACKGROUND: Liver steatosis was caused by lipid accumulation in the liver. Alisma orientale (AO) is recognized as a promising candidate with therapeutic efficacy for the treatment of nonalcoholic fatty liver disease (NAFLD). HepG2 hepatocyte cell line is commonly used for liver disease cell model. METHOD: The HepG2 cells were cultured with the NEFAs mixture (oleic and palmitic acids, 2:1 ratio) for 24 h to induce hepatic steatosis. Then different doses of Alisma orientale extract (AOE) was treated to HepG2 for 24 h. Incubated cells were used for further experiments. RESULTS: The AOE showed inhibitory effects on lipid accumulation in the Oil Red O staining and Nile red staining tests with no cytotoxicity at a concentration of 300 µg/mL. Fatty acid synthase (FASN) and acetyl-CoA carboxylase 1 (ACC1) mRNA and protein expression level were down-regulated after AOE treatment. Bcl-2 associated X protein (Bax) and c-Jun N-terminal kinase (JNK) mRNA expression level were decreased as well as p-JNK (activated form of JNK), Bax, cleaved caspase-9, caspase-3 protein expression level. Anti-apopototic B-cell lymphoma 2 (Bcl-2) protein level increased after AOE treatment. In addition, inflammatory protein expression including p-p65, p65, COX-2 and iNOS were inhibited by AOE treatment. CONCLUSION: The results suggest that AOE has anti-steatosis effects that involve lipogenesis, anti-lipoapoptosis, and anti-inflammation in the NEFA-induced NAFLD pathological cell model.


Assuntos
Alisma/química , Apoptose/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Lipogênese/genética , Extratos Vegetais/química
3.
Chemosphere ; 353: 141429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38364917

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) comprise a group of compounds resulting from the incomplete combustion of organic matter. Firefighters engaged in fire suppression are highly exposed to PAHs. This study centered on evaluating the exposure levels and health risks of PAHs in South Korean firefighters involved in firefighting activities. The concentrations of 10 PAH metabolites in the urine of firefighters were measured immediately after, and two weeks post their engagement in extinguishing a large tire factory fire. The levels of OH-PAHs in urine samples immediately after fire suppression were elevated by a factor of 1.01-1.84 compared to urine samples from non-exposed period. The median concentration of total PAH metabolites (OH-PAHs) was higher in urine samples immediately after fire suppression (5910 ng/g creatinine) than in urine samples from non-exposed periods (5020 ng/g creatinine). However, the ∑OH-PAH levels in firefighters' urine were related to personal habits such as smoking. The concentrations of all individual OH-PAHs in the urine samples of nonsmokers exhibited a substantial increase, ranging from 1.37 to 2.3 times, clearly demonstrating that firefighting activities were a substantial source of PAH exposure. The calculated values associated with the health risks stemming from exposure to PAHs, including carcinogenic risk, total estimated daily intake (TEDI), and hazard quotients/index (HQs/HI), all fell within acceptable limits, indicating negligible risk. However, the HQ/HI values and TEDI for individual and total PAH exposures, except those for naphthalene, were 1.36-2.00 times higher in firefighters' samples taken after firefighting operations compared to those during regular duty. This underscores the need for more comprehensive investigations to comprehend the singular impact of firefighting activities due to the diverse sources of PAH emissions in the environment.


Assuntos
Poluentes Ocupacionais do Ar , Bombeiros , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Poluentes Ocupacionais do Ar/análise , Exposição Ocupacional/análise , Creatinina , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
J Neurogastroenterol Motil ; 24(2): 307-316, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29433301

RESUMO

BACKGROUND/AIMS: Fructose malabsorption (FM) mimics symptoms of irritable bowel syndrome (IBS), and its prevalence has increased. Diagnosing FM in IBS is challenging because of its overlap with small intestinal bacterial overgrowth (SIBO). We assessed the prevalence of FM by comparing patients with IBS with asymptomatic control individuals after excluding SIBO using the glucose hydrogen breath test (HBT). METHODS: Patients diagnosed with IBS and asymptomatic control individuals were enrolled prospectively. Dietary habits were assessed with the Food Frequency Questionnaire. After excluding SIBO, participants underwent HBTs with both 15 g and 25 g of fructose. RESULTS: Thirty-five patients with IBS and 35 age- and sex-matched asymptomatic control individuals were enrolled. The 15-g fructose HBT yielded positive results in 7 of the 35 (20.0%) patients with IBS and in 2 of 35 (5.7%) controls (P = 0.070). The 25-g fructose HBT was positive in 16 of the 35 (45.7%) patients with IBS and in 8 of the 35 (22.9%) controls (P = 0.040). Analysis of the Food Frequency Questionnaire responses showed no significant differences between the 2 groups in dietary intake, although patients with IBS showed a significantly higher mean fiber intake than controls (21.24 ± 11.35 g vs 15.87 ± 7.07 g, respectively, P = 0.040). CONCLUSIONS: The 25-g fructose HBT identified FM in a significantly higher percentage of SIBO-negative patients with IBS than in asymptomatic control individuals, suggesting that FM may correlate with IBS. Education regarding dietary control of foods containing fructose may be useful for the management of patients with IBS.

5.
Phytomedicine ; 22(13): 1201-5, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26598920

RESUMO

BACKGROUND: Although herbal medicines (HMs) are widely used in Asian and Western countries, medicinal information concerning their hepatic toxicity or interaction with conventional medicines (CMs) is sparse. PURPOSE: The aim of our study was to estimate the prevalence of drug-induced liver injury (DILI) among total inpatients prescribed HMs or CMs. Furthermore, we noted all medications suspected to be associated with hepatotoxicity in the liver injury group during the period of hospitalization. STUDY DESIGN: We retrospectively observed medical records of 1169 inpatients in a single medical center from January 2012 to July 2014. METHODS: Based on a database of the 1169 inpatients at a single medical center, we researched the occurrence rate and type of liver injury according to the criteria of the Council for International Organization of Medical Science (CIOMS). We also utilized a simplified Roussel Uclaf Causality Assessment Method (RUCAM) score for probable causality assessment between drugs and liver injury. RESULTS: Among a total of 1169 inpatients, 13 cases whose baseline LFTs had been in the normal range at admission had abnormal liver parameters at the time of follow-up, and 11 of them (0.94%) were attributed to drugs: 0.43% (5 of 1169) to HMs, 0.43% (5 of 1169) to CMs, and 0.09% (1 of 1169) to combined drug classes. Two of them were found to have liver injury because of pneumonia and sepsis. As for liver injury type, 8 cases were hepatocellular, 2 were cholestatic, and 1 was of mixed pattern. The common causative HMs for hepatotoxicity were Ephedrae Herba and Scutellariae Radix, while CMs included antidepressants, antihistamines, and antibacterials. CONCLUSIONS: We investigated approximate incidence rates and analyzed suspicious drugs associated with liver damage, which revealed a low frequency of liver injury induced by HMs. However, further study, based on a well-designed, long-term, multicenter prospective study, will be required to determine the safety of HMs.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Preparações de Plantas/efeitos adversos , Adulto , Idoso , Antibacterianos/efeitos adversos , Antidepressivos/efeitos adversos , Ephedra/efeitos adversos , Feminino , Antagonistas dos Receptores Histamínicos/efeitos adversos , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Estudos Retrospectivos , Scutellaria/efeitos adversos
6.
J Colloid Interface Sci ; 257(2): 179-87, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16256470

RESUMO

The nature of the interaction among Cu(II), adsorbed water, and quartz surface was studied using electron paramagnetic resonance (EPR) spectroscopy. The EPR lineshape gave information concerning the motional status of sorbed Cu(II) that revealed its binding strength at the surface. Two distinct absorption lines of sorbed Cu(II), namely, the liquid-type and the solid-type signal, were simultaneously observed at the fully hydrated surface at room temperature. The absorption lines and the variation of their intensity with experimental and measurement conditions such as degree of hydration, pH, ionic strength, and surface coverage indicated that there exist three kinds of Cu(II) entities, the inner-sphere surface complex, the outer-sphere surface complex, and the surface precipitate on the quartz surface, and that their concentrations change with experimental conditions. The reversible conversion of the liquid-type signal to the solid-type one during the drying-wetting or freezing-melting of the surface suggested the development of multiple layers of adsorbed water molecules on the quartz surface. It is assumed that the innermost layer of the water layers contains the inner-sphere Cu(II) surface complexes, while the outer layers contain the outer-sphere complexes whose binding strength decreases outward with increasing distance from the surface. The result of this work suggests that the sorption mechanism of a metal cation on a given mineral surface; hence its mobility in the environment may change significantly with the solution pH, the ionic strength, and the surface coverage.

7.
Anal Chim Acta ; 787: 111-7, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23830428

RESUMO

A sensitive gas chromatographic mass spectrometric (GC-MS) method has been established for the simultaneous determination of acetamide (AA), propanamide (PA), and butyramide (BA) in surface and drinking water based on derivatization with 9-xanthydrol. Deuterated acrylamide was chosen as the internal standard for analyzing the water sample. The derivatization of AA, PA, and BA was performed directly in water and the reaction conditions (10.0-mM 9-xanthydrol, 0.5-M HCl, 20-min reaction time, and ambient temperature) were established. Under these conditions, the detection limit of the analytes was 0.03 µg L(-1), and the interday relative standard deviation was less than 16% at concentrations of 1.0, 5.0 and 10.0 µg L(-1). The proposed GC-MS method enables the reliable analysis of trace AA, PA, and BA in environmental water.


Assuntos
Acetamidas/análise , Amidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Propionatos/análise , Poluentes Químicos da Água/análise , Xantenos/química
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