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1.
Nanomaterials (Basel) ; 13(23)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38063760

RESUMEN

Sulfide electrolyte all-solid-state lithium-ion batteries (ASSLBs) that have inherently nonflammable properties have improved greatly over the past decade. However, determining both the stable and functional electrode components to pair with these solid electrolytes requires significant investigation. Solid electrolyte comprises 20-40% of the composite cathode electrode, which improves the ionic conductivity. However, this results in thick electrolyte that blocks the electron pathways in the electrode, significantly lowering the electrochemical performance. The application of conductive carbon material is required to overcome this issue, and, hence, determining the carbon properties that result in the most stable performance in the sulfide solid electrolyte is vital. This study analyzes the effect of the cathode conductive additive's morphology on the electrochemical performance of sulfide electrolyte-based ASSLBs. Carbon black (CB) and carbon nanotubes (CNTs), which provide electron pathways at the nanoscale and sub-micron scale, and carbon nanofiber (CNF), which provides electron pathways at the tens-of-microns scale, are all tested individually as potential conductive additives. When the CNF, with its high crystallinity, is used as a conductive material, the electrochemical performance shows an excellent initial discharge capacity of 191.78 mAh/g and a 50-cycle capacity retention of 83.9%. Conversely, the CB and the CNTs, with their shorter pathways and significantly increased surface area, show a relatively low electrochemical performance. By using the CNF to provide excellent electrical conductivity to the electrode, the polarization is suppressed. Furthermore, the interfacial impedance across the charge transfer region is also reduced over 50 cycles compared with the CB and CNT composite cells. These findings stringently analyze and emphasize the importance of the morphology of the carbon conductive additives in the ASSLB cathode electrodes, with improvements in the electrochemical performance being realized through the application of long-form two-dimensional crystalline CNFs.

2.
Nanomaterials (Basel) ; 12(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36500894

RESUMEN

Lithium-ion batteries (LIBs) continue to dominate the battery market with their efficient energy storage abilities and their ongoing development. However, at high charge/discharge C-rates their electrochemical performance decreases significantly. To improve the power density properties of LIBs, it is important to form a uniform electron transfer network in the cathode electrode via the addition of conductive additives. Carbon nanotubes (CNTs) with high crystallinity, high electrical conductivity, and high aspect ratio properties have gathered significant interest as cathode electrode conductive additives. However, due to the high aggregational properties of CNTs, it is difficult to form a uniform network for electron transfer within the electrode. In this study, to help fabricate electrodes with well-dispersed CNTs, various electrodes were prepared by controlling (i) the mixing order of the conductive material, binder, and active material, and (ii) the sonication process of the CNTs/NMP solution before the electrode slurry preparation. When the binder was mixed with a well sonicated CNTs/NMP solution, the CNTs uniformly adsorbed to the then added cathode material of LiNi0.6Co0.2Mn0.2O2 and were well-dispersed to form a flowing uniform network. This electrode fabrication process achieved > 98.74% capacity retention after 50 cycles at 5C via suppressed polarization at high current densities and a more reversible H1-M phase transition of the active material. Our study presents a novel design benchmark for the fabricating of electrodes applying well-dispersed CNTs, which can facilitate the application of LIBs in high current density applications.

3.
Food Sci Biotechnol ; 29(9): 1187-1194, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32802557

RESUMEN

To improve the industrial use of health-functional materials based on edible insects, the objective of this study was to establish optimal conditions for improving the quality of Protaetia brevitarsis seulensis larval (PBSL) hydrolysates. PBSL was extracted using four methodologies: atmospheric pressure 50 °C-water extraction, atmospheric pressure 95 °C-water extraction, atmospheric pressure 50 °C-water enzymatic hydrolysis, and enzyme treatment under high pressure (HPE). The quality characteristics of soluble solid content, extraction yield, total protein content, protein yield, protein content with low molecular weight (LMW) (< 1kD), and the amino acid composition of hydrolysates were compared based on the different methods. All of the quality characteristics were found to be higher for HPE extracts than for the other extracts. Under optimized HPE conditions, extraction yield, protein yield, protein content with LMW, amino acid content and the content of essential amino acids increased by 3.4, 4.4 1.4 1.5, and 1.3 times respectively, compared to the other methods.

4.
Nutr Res Pract ; 14(3): 286-297, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32528635

RESUMEN

BACKGROUND/OBJECTIVES: This study compared the perception of customers from Korea and the U.S. on the attributes of different formats of menu labeling The specific objectives were 1) to compare the customers' perceived usefulness, ease-of-understanding, clarity, and attractiveness of different formats of menu labeling between Korea and the U.S.; and 2) to compare the customers' use intention to different formats of menu labeling between Korea and the U.S. SUBJECTS/METHODS: A survey was conducted in Korea and the U.S. The participants were allocated randomly to view 1 of the 7 restaurant menus that varied according to the following types of menu labeling formats: (type 1) kcal format, (type 2) traffic-light format, (type 3) percent daily intake (%DI) format, (type 4) kcal + traffic-light format, (type 5) kcal + %DI format, (type 6) traffic-light + %DI format, and (type 7) kcal + traffic-light + %DI format. A total of 279 Koreans and 347 Americans were entered in the analysis. An independent t-test and 1-way analysis of variance were performed. RESULTS: Koreans rated type 4 format (kcal + traffic light) the highest for usefulness and attractiveness. In contrast, Americans rated type 7 (kcal + traffic light + %DI) the highest for usefulness, ease-of-understanding, attractiveness, and clarity. Significant differences were found in the customers' perceived attributes to menu labeling between Korea and the U.S. Americans perceived higher for all the 4 attributes of menu labeling than Koreans. CONCLUSIONS: The study is unique in identifying the differences in the attributes of different formats of menu labeling between Korea and the U.S. Americans rated the most complicated type of menu labeling as the highest perception for the attributes, and showed a higher use intention of menu labeling than Koreans. This study contributes to academia and industry for practicing menu labeling in different countries using different formats.

5.
Environ Monit Assess ; 190(11): 677, 2018 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-30368600

RESUMEN

Although medicines are less toxic than other toxicants, increased production and usage of pharmaceuticals have led to many concerns regarding their toxic effects on human and non-target organisms. Additionally, reproductive toxicity after long-term exposure is difficult to anticipate. Tamoxifen (TAM), a selective estrogen receptor modulator, has been widely used as an anticancer drug for mammalian breast and endometrial cancers. With increased TAM usage, it has frequently been reported that TAM is a potential endocrine disruptor capable of interfering with reproduction in non-target organisms. However, the mode of action of TAM in the endocrine system is unknown. In this study, we performed a 21-day chronic toxicity test using the crustacean Daphnia magna and investigated the transcriptional modulation of major genes related to the endocrine system, molting, development, and reproduction (i.e., Dm-vtg2, vmo1, cyp314, usp, and ecrb) after TAM exposure for 3, 6, 12, and 24 h. Our results showed a concentration-dependent decrease in the total number of offspring per individual, except for the concentration 25 µg/L; additionally, the expression of oogenesis-related genes was induced early but was later inhibited by TAM exposure. Additionally, molting-related genes were also downregulated in a time-dependent manner. Our findings suggested that TAM regulates reproduction by interfering with the molecular mechanisms involved in oogenesis and molting. This study supports the hypothesis that D. magna are a useful model to rapidly evaluate the reproductive effects of pharmaceuticals.


Asunto(s)
Daphnia/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Reproducción/efectos de los fármacos , Tamoxifeno/toxicidad , Animales , Monitoreo del Ambiente/métodos , Femenino , Pruebas de Toxicidad Crónica , Contaminantes Químicos del Agua/toxicidad
6.
Aquat Toxicol ; 196: 35-42, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29328974

RESUMEN

Because of its widespread use, the pharmaceutical acetaminophen (APAP) is frequently detected in aquatic environments. APAP can have serious physiological effects, such as reduced reproduction, low growth rates, and abnormal behavior, in aquatic organisms. However, the methods available for evaluation of the aquatic toxicity of APAP are of limited usefulness. The present study aimed to develop reliable and sensitive markers for evaluation of APAP toxicity using Daphnia as a model organism. We focused on N-acetyl-p-benzoquinoneimine (NAPQI) production from APAP via cytochrome P450 metabolism because NAPQI causes APAP toxicity. Daphnia magna were exposed to APAP (0, 50, or 100 mg/L for 12 h or 24 h), and the total metabolites were extracted and analyzed for NAPQI. Direct detection of NAPQI was difficult because of its high reactivity, and its peak was close to that for APAP. Therefore, we tried to identify molecular and biochemical indicators associated with NAPQI generation, elimination, and its interactions with macromolecules. We identified changes in CYP370A13 gene expression, glutathione depletion, inhibition of thioredoxin reductase activity, and production of reactive oxygen species as indicators of D. magna exposure to APAP. These indicators could be used to develop sensitive and accurate techniques to evaluate the environmental toxicity of APAP.


Asunto(s)
Acetaminofén/toxicidad , Sistema Enzimático del Citocromo P-450/metabolismo , Daphnia/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Acetaminofén/análisis , Acetaminofén/metabolismo , Animales , Benzoquinonas/análisis , Benzoquinonas/toxicidad , Cromatografía Líquida de Alta Presión , Sistema Enzimático del Citocromo P-450/genética , Daphnia/metabolismo , Expresión Génica/efectos de los fármacos , Glutatión/metabolismo , Iminas/análisis , Iminas/toxicidad , Inactivación Metabólica , Masculino , Especies Reactivas de Oxígeno/metabolismo , Reductasa de Tiorredoxina-Disulfuro/metabolismo
7.
Endocr J ; 64(3): 303-314, 2017 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-28049882

RESUMEN

Circulating neutrophil gelatinase-associated lipocalin (NGAL) is associated with obesity-related metabolic disorders. This study investigated the relationship between serum NGAL and early alteration of metabolic parameters in non-diabetic Korean women, particularly with respect to saturated fat (SFA) intake. Anthropometric parameters, fasting glycemic status, and levels of lipids, oxidative stress/inflammatory markers, and NGAL were measured in 82 non-diabetic Korean women [Super-healthy group (n=57) with 0 metabolic syndrome risk factor (MetS RF) and MetS-risk group (n=25) with MetS RF≥1]. Age, weight, waist circumference, blood pressure, fasting glucose, HbA1C, triglyceride, LDL and total-cholesterol, and NGAL levels were higher, and HDL-cholesterol was lower in the MetS-risk group than in the Super-healthy group. Age-adjusted serum NGAL levels were higher in the MetS-risk group than in the Super-healthy group. NGAL increased proportionally with increase in MetS RFs (p=0.038) and correlated positively with BMI, triglycerides, LDL- and total-cholesterol, interleukin-6, white blood cell count, and neutrophil%, and negatively with HDL-cholesterol and superoxide dismutase activity. Serum NGAL levels positively correlated with SFA intake before and after adjustment (age and BMI). Serum NGAL levels were higher in high-SFA consumers [≥7g/day, ≥7% of total calorie intake (TCI)] than in low-SFA consumers (<7g/day, <7% of TCI). Serum NGAL levels were highest in the MetS-risk group consuming higher SFA and lowest in the Super-healthy group consuming lower SFA. However, serum NGAL did not significantly differ between the low-SFA consuming MetS-risk and Super-healthy groups. The relationship between circulating NGAL and early alteration of metabolic parameters is associated with dietary SFA intake in non-diabetic Korean women.


Asunto(s)
Grasas de la Dieta/efectos adversos , Lipocalina 2/sangre , Síndrome Metabólico/etiología , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Regulación hacia Arriba , Adulto , Biomarcadores/sangre , Índice de Masa Corporal , Estudios Transversales , Diagnóstico Precoz , Femenino , Humanos , Interleucina-6/sangre , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , Obesidad/sangre , Obesidad/inmunología , Sobrepeso/sangre , Sobrepeso/inmunología , Estrés Oxidativo , República de Corea/epidemiología , Factores de Riesgo , Factor de Necrosis Tumoral alfa/sangre , Circunferencia de la Cintura
8.
Food Chem ; 135(4): 2350-8, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22980812

RESUMEN

Saffron (Crocus sativus Linn.) has been an important subject of research in the past two decades because of its various biological properties, including anti-cancer, anti-inflammatory, and anti-atherosclerotic activities. On the other hand, the molecular bases of its actions have been scarcely understood. Here, we elucidated the mechanism of the hypoglycemic actions of saffron through investigating its signaling pathways associated with glucose metabolism in C(2)C(12) skeletal muscle cells. Saffron strongly enhanced glucose uptake and the phosphorylation of AMPK (AMP-activated protein kinase)/ACC (acetyl-CoA carboxylase) and MAPKs (mitogen-activated protein kinases), but not PI 3-kinase (Phosphatidylinositol 3-kinase)/Akt. Interestingly, the co-treatment of saffron and insulin further improved the insulin sensitivity via both insulin-independent (AMPK/ACC and MAPKs) and insulin-dependent (PI 3-kinase/Akt and mTOR) pathways. It also suggested that there is a crosstalk between the two signaling pathways of glucose metabolism in skeletal muscle cells. These results could be confirmed from the findings of GLUT4 translocation. Taken together, AMPK plays a major role in the effects of saffron on glucose uptake and insulin sensitivity in skeletal muscle cells. Our study provides important insights for the possible mechanism of action of saffron and its potential as a therapeutic agent in diabetic patients.


Asunto(s)
Crocus/química , Glucosa/metabolismo , Resistencia a la Insulina , Células Musculares/metabolismo , Extractos Vegetales/farmacología , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Línea Celular , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Células Musculares/efectos de los fármacos , Músculo Esquelético/citología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Regulación hacia Arriba/efectos de los fármacos
9.
Bioorg Med Chem Lett ; 22(7): 2522-6, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22374216

RESUMEN

Following the previous SAR of a novel dihydropyrimidinone scaffold as HIV-1 replication inhibitors a detailed study directed towards optimizing the metabolic stability of the ester functional group in the dihydropyrimidinone (DHPM) scaffold is described. Replacement of the ester moiety by thiazole ring significantly improved the metabolic stability while retaining antiviral activity against HIV-1 replication. These novel and potent DHPMs with bioisosteres could serve as advanced leads for further optimization.


Asunto(s)
Transcriptasa Inversa del VIH/antagonistas & inhibidores , VIH-1/efectos de los fármacos , Pirimidinonas/síntesis química , Inhibidores de la Transcriptasa Inversa/síntesis química , Replicación Viral/efectos de los fármacos , Animales , Línea Celular Tumoral , Estabilidad de Medicamentos , VIH-1/fisiología , Humanos , Microsomas Hepáticos/metabolismo , Modelos Moleculares , Nevirapina/farmacología , Pirimidinonas/farmacología , Ratas , Inhibidores de la Transcriptasa Inversa/farmacología , Relación Estructura-Actividad , Tiazoles/química
10.
Bioorg Med Chem Lett ; 22(5): 2119-24, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22305583

RESUMEN

3,4-Dihydropyrimidin-2(1H)-ones (DHPMs) were selected and derivatized through a HIV-1 replication assay based on GFP reporter cells. Compounds 14, 25, 31, and 36 exhibited significant inhibition of HIV-1 replication with a good safety profile. Chiral separation of each enantiomer by fractional crystallization showed that only the S enantiomer retained anti-HIV activity. Compound (S)-40, a novel and potent DHPM analog, could serve as an advanced lead for further development and the determination of the mechanism of action.


Asunto(s)
Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Pirimidinonas/química , Pirimidinonas/farmacología , Replicación Viral/efectos de los fármacos , Diseño de Fármacos , Infecciones por VIH/tratamiento farmacológico , Humanos , Estereoisomerismo , Relación Estructura-Actividad
11.
ACS Med Chem Lett ; 3(8): 678-82, 2012 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-24900529

RESUMEN

We identified a novel class of aryl-substituted triazine compounds as potent non-nucleoside reverse transcriptase inhibitors (NNRTIs) during a high-throughput screening campaign that evaluated more than 200000 compounds for antihuman immunodeficiency virus (HIV) activity using a cell-based full replication assay. Herein, we disclose the optimization of the antiviral activity in a cell-based assay system leading to the discovery of compound 27, which possessed excellent potency against wild-type HIV-1 (EC50 = 0.2 nM) as well as viruses bearing Y181C and K103N resistance mutations in the reverse transcriptase gene. The X-ray crystal structure of compound 27 complexed with wild-type reverse transcriptase confirmed the mode of action of this novel class of NNRTIs. Introduction of a chloro functional group in the pyrazole moiety dramatically improved hERG and CYP inhibition profiles, yielding highly promising leads for further development.

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