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1.
Chem Commun (Camb) ; 59(18): 2604-2607, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36756797

RESUMEN

Conventional distillation methods cannot separate compounds with similar boiling points, molecular sizes, and volumes, such as cyclohexane and benzene or methylcyclohexane and toluene, effectively. The corresponding cyclic aliphatic and aromatic hydrocarbons cannot be separated effectively using the same type of sorption material. We report that crystalline thiacalixarene assemblies featuring preorganized channel-like adsorption sites are capable of both separations.

2.
ACS Omega ; 4(6): 9763-9768, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31460067

RESUMEN

A delafossite-type Ag-Mn oxide was successfully synthesized using the precipitation method at room temperature. The delafossite is Ag+-deficient and has a chemical composition of Ag0.9MnO2. Thermogravimetry of the Ag0.9MnO2 delafossite revealed that on heating to 900 °C, it decomposed to Ag and Mn2O3 in air and to Ag and Mn3O4 under N2. While cooling to room temperature in air, the delafossite phase reformed from Ag and Mn3O4. The reversibility of the decomposition/reformation process is related to the similarity between the delafossite and spinel-type structures, both of which contain an octahedral layer. The reformation process could be used as a new synthetic route to Ag+-containing delafossite-type oxides.

3.
J Diabetes Investig ; 7(3): 386-95, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27330726

RESUMEN

AIMS/INTRODUCTION: We carried out an observational cohort study to examine the relationship between the efficacy of oral antidiabetic drugs and clinical features in type 2 diabetics. MATERIALS AND METHODS: We analyzed the CoDiC(®) database of the Japan Diabetes Data Management Study Group across 67 institutions in Japan. In a total of 3,698 drug-naïve patients who were initiated with metformin, dipeptidyl peptidase-4 inhibitor (DPP-4i) or sulfonylurea (SU) from 2007 to 2012, we evaluated body mass index (BMI) and hemoglobin A1c (HbA1c). The patients were stratified according to their clinical features, and matched using a propensity score to adjust for baseline factors. RESULTS: HbA1c was reduced with all drugs, with the largest effect elicited by DPP-4i and the smallest by SU (P = 0.00). HbA1c increased with SU after 6 months in the patients stratified by an age-of-onset of <50 years (P = 0.00). BMI increased with SU in the patients stratified by a BMI of <25 (P = 0.00), and decreased with metformin in the patients with a BMI >25 (P = 0.00). The reduction in HbA1c was larger in patients with HbA1c of ≥8%, compared with that in patients with HbA1c of <8% (P = 0.00). HbA1c during the study period was higher in patients who were added to or swapped with other drug(s), than in patients continued on the original drug (P = 0.00). CONCLUSIONS: The effect on bodyweight and glycemic control differed among metformin, DPP-4i and SU, and the difference was associated with clinical features.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Compuestos de Sulfonilurea/uso terapéutico , Administración Oral , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Diabetes Mellitus Tipo 2/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/administración & dosificación , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/administración & dosificación , Masculino , Metformina/administración & dosificación , Persona de Mediana Edad , Puntaje de Propensión , Compuestos de Sulfonilurea/administración & dosificación , Resultado del Tratamiento
4.
Anal Chem ; 78(22): 7850-6, 2006 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-17105179

RESUMEN

Gibbs monolayers of lipophilic tetraphenylporphyrinatomanganese(III) and hydrophilic diacid of meso-tetrakis(4-sulfonatopheny)porphyrin adsorbed at the liquid-liquid interface have been analyzed by UV-visible external reflection (ER) and partial internal reflection (PIR) spectra measured at different angles of incidence. The angle-dependent ER and PIR spectra over the Brewster angles (thetaERB and thetaIRB) have readily been measured at the toluene/water interface. As preliminarily expected in our previous study, the present study has first proved that the reflection-absorbance of UV-visible PIR spectra quantitatively agrees with the theoretical calculations for the Gibbs monolayer over thetaIRB. In addition, it has also been proved that the absorbance of the PIR spectra is greatly enhanced in comparison to that of the ATR spectra. The enhancement is caused by an optical effect in the monolayer sandwiched between two phases of toluene and water that have different but refractive indices close to each other. This optical enhancement requires an optically perfect contact between the phases, which is difficult to prepare for a solid-solid contact. At the liquid/liquid interface, however, an ideal optical contact is easily realized, which makes the enhancement as much as the theoretical expectation. The PIR spectrometry will be recognized to be a new high-sensitive analytical tool to study Gibbs monolayer at the liquid/liquid interface.


Asunto(s)
Manganeso/química , Membranas Artificiales , Compuestos Organometálicos/química , Porfirinas/química , Tolueno/química , Agua/química , Ácidos/química , Adsorción , Cationes , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Análisis Espectral/métodos , Propiedades de Superficie , Factores de Tiempo
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