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1.
J Clin Med ; 11(13)2022 Jul 04.
Article in English | MEDLINE | ID: mdl-35807188

ABSTRACT

This study's goal is to determine the accuracy of a linear classifier that predicts the prognosis of patients with macular edema (ME) due to a branch retinal vein occlusion during the maintenance phase of antivascular endothelial growth factor (anti-VEGF) therapy. The classifier was created using the clinical information and optical coherence tomographic (OCT) findings obtained up to the time of the first resolution of ME. In total, 66 eyes of 66 patients received an initial intravitreal injection of anti-VEGF followed by repeated injections with the pro re nata (PRN) regimen for 12 months. The patients were divided into two groups: those with and those without good vision during the PRN phase. The mean AUC of the classifier was 0.93, and the coefficients of the explanatory variables were: best-corrected visual acuity (BCVA) at baseline was 0.66, BCVA at first resolution of ME was 0.51, age was 0.21, the average brightness of the ellipsoid zone (EZ) was -0.12, the intactness of the external limiting membrane (ELM) was -0.14, the average brightness of the ELM was -0.17, the brightness value of EZ was -0.17, the area of the outer segments of the photoreceptors was -0.20, and the intactness of the EZ was -0.24. This algorithm predicted the prognosis over time for individual patients during the PRN phase.

3.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1501-1508, 2022 May.
Article in English | MEDLINE | ID: mdl-34773490

ABSTRACT

PURPOSE: To identify the eyes with macular edema (ME) due to a branch retinal vein occlusion (BRVO) that have good visual acuity during the continuous anti-vascular endothelial growth factor (anti-VEGF) treatment based on the patients' clinical information and optical coherence tomography (OCT) images by using machine learning. METHODS: Sixty-six eyes of 66 patients received 1 anti-VEGF injection followed by repeated injections in the pro re nata (PRN) regimen for 12 months. The patients were divided into two groups: those with and those without good vision during the 1-year experimental period. Handcraft features were defined from the OCT images at the time of the first resolution of the ME. Variables with a significant difference between the groups were used as explanatory variables. A classifier was created with handcrafted features based on a support vector machine (SVM) that adjusted parameters for increasing maximal precision. RESULTS: The age, best-corrected visual acuity (BCVA) at the baseline, BCVA at the first resolution of the ME, integrity and reflectivity of the external limiting membrane (ELM), the ellipsoid zone (EZ), and area of the outer segments of the photoreceptors were selected as explanatory variables. The classification performance was 0.806 for accuracy, 0.768 for precision, 0.772 for recall, and 0.752 for the F-measure. CONCLUSION: The use of the SVM of the patient's clinical information and OCT images can be helpful for determining the prognosis of the BCVA during continued pro re nata anti-VEGF treatment in eyes with ME associated with BRVO.


Subject(s)
Macular Edema , Retinal Vein Occlusion , Angiogenesis Inhibitors , Humans , Intravitreal Injections , Macular Edema/diagnosis , Macular Edema/drug therapy , Macular Edema/etiology , Retinal Vein Occlusion/complications , Retinal Vein Occlusion/diagnosis , Retinal Vein Occlusion/drug therapy , Retrospective Studies , Support Vector Machine , Tomography, Optical Coherence/methods , Treatment Outcome , Visual Acuity
4.
Nanomaterials (Basel) ; 11(3)2021 Mar 08.
Article in English | MEDLINE | ID: mdl-33800336

ABSTRACT

Hydroxyapatite is known to have excellent catalytic properties for ethanol conversion and lactic acid conversion, and their properties are influenced by the elemental composition, such as Ca/P ratio and sodium content. However, few reports have been examined for the surface acid-base nature of hydroxyapatites containing sodium ions. We prepared nanocrystalline hydroxyapatite (Ca-HAP) catalysts with various Ca/P ratios and sodium contents by the hydrothermal method. The adsorption and desorption experiments using NH3 and CO2 molecules and the catalytic reactions for 2-propenol conversion revealed that the surface acid-base natures changed continuously with the bulk Ca/P ratios. Furthermore, the new catalytic properties of hydroxyapatite were exhibited for 1,6-hexanediol conversion. The non-stoichiometric Ca-HAP(1.54) catalyst with sodium ions of 2.3 wt% and a Ca/P molar ratio of 1.54 gave a high 5-hexen-1-ol yield of 68%. In contrast, the Ca-HAP(1.72) catalyst, with a Ca/P molar ratio of 1.72, gave a high cyclopentanemethanol yield of 42%. Both yields were the highest ever reported in the relevant literature. It was shown that hydroxyapatite also has excellent catalytic properties for alkanediol conversion because the surface acid-base properties can be continuously controlled by the elemental compositions, such as bulk Ca/P ratios and sodium contents.

5.
RSC Adv ; 11(51): 32300-32304, 2021 Sep 27.
Article in English | MEDLINE | ID: mdl-35495519

ABSTRACT

Bare TiO2 photocatalyst almost quantitatively converted nitrobenzene to aniline with various saccharides without the use of hydrogen gas. Although aniline was formed when any saccharide was used, the use of disaccharides (lactose, maltose, and sucrose) decreased the reaction rate. The rate of photocatalytic hydrogenation of nitrobenzene using saccharides is determined by the degradation rate of saccharides at positive holes. When glucose was used, formic acid, arabinose, glyceraldehyde and lactic acid were obtained, which are products that are consistent with the product of the photocatalytic oxidation of glucose.

6.
ACS Omega ; 5(38): 24964-24972, 2020 Sep 29.
Article in English | MEDLINE | ID: mdl-33015516

ABSTRACT

Sulfonated solid acid materials, such as sulfonated carbon catalysts, are promising materials as heterogeneous catalysts for the hydrolysis of esters and polysaccharides in water solvents. The catalytic active site is a sulfonic acid functional group. Compared to conventional strong acidic ion-exchange resin catalysts, sulfonated carbon materials have less sulfonic acid functional groups but higher catalytic activity for hydrolysis of polysaccharides per catalyst weight. However, the details of catalytic properties and the substrate suitability of both catalysts are unclear. In this study, the hydrolytic activities and the adsorption properties of both catalysts were investigated for various oligosaccharides and polysaccharides with varying degrees of polymerization (DP). The catalytic activities for the hydrolysis with increase of the DP of saccharides were found to increase over the sulfonated carbon catalyst but decrease over strong acidic ion-exchange resin catalyst. The inverse catalytic properties attribute to the dependence of the amounts of adsorption and/or penetration of saccharides on the DP. Moreover, the catalytic activity per acidic sites of strong acidic ion-exchange resin is in good agreement with the value obtained by multiplying the catalytic activity of a dilute sulfuric acid by the penetration degrees.

7.
Chem Commun (Camb) ; 54(53): 7298-7301, 2018 Jun 28.
Article in English | MEDLINE | ID: mdl-29789832

ABSTRACT

In the presence of a palladium-loaded TiO2 photocatalyst, the cleavage of benzyl phenyl ether in low-molecular-weight alcohol solvents under de-aerated conditions afforded toluene and phenol simultaneously in a 1 : 1 molar ratio.

8.
Phys Chem Chem Phys ; 20(29): 19321-19325, 2018 Jul 25.
Article in English | MEDLINE | ID: mdl-29808859

ABSTRACT

A copper-loaded titanium(iv) oxide photocatalyst exhibited perfect selectivity in hydrogenation of alkynes to alkenes in an alcohol solution at 298 K under hydrogen-free and poison-free conditions. A slight elevation in the reaction temperature to 323 K greatly increased the reaction rate with the selectivity being preserved and the formation of an H2 by-product being suppressed. The apparent activation energy of 4-octyne semihydrogenation was determined to be 54 kJ mol-1, indicating that the rate determining step of this photocatalytic reaction was not an electron production process but a thermocatalytic hydrogenation process under light irradiation.

9.
Sci Adv ; 3(4): e1602747, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28508046

ABSTRACT

Ammonia has been suggested as a carbon-free hydrogen source, but a convenient method for producing hydrogen from ammonia with rapid initiation has not been developed. Ideally, this method would require no external energy input. We demonstrate hydrogen production by exposing ammonia and O2 at room temperature to an acidic RuO2/γ-Al2O3 catalyst. Because adsorption of ammonia onto the catalyst is exothermic, the catalyst bed is rapidly heated to the catalytic ammonia autoignition temperature, and subsequent oxidative decomposition of ammonia produces hydrogen. A differential calorimeter combined with a volumetric gas adsorption analyzer revealed a large quantity of heat evolved both with chemisorption of ammonia onto RuO2 and acidic sites on the γ-Al2O3 and with physisorption of multiple ammonia molecules.

10.
Chem Sci ; 8(1): 674-679, 2017 Jan 01.
Article in English | MEDLINE | ID: mdl-28451216

ABSTRACT

Ammonia is a crucial chemical feedstock for fertilizer production and is a potential energy carrier. However, the current method of synthesizing ammonia, the Haber-Bosch process, consumes a great deal of energy. To reduce energy consumption, a process and a substance that can catalyze ammonia synthesis under mild conditions (low temperature and low pressure) are strongly needed. Here we show that Ru/Pr2O3 without any dopant catalyzes ammonia synthesis under mild conditions at 1.8 times the rates reported with other highly active catalysts. Scanning transmission electron micrograph observations and energy dispersive X-ray analyses revealed the formation of low-crystalline nano-layers of ruthenium on the surface of Pr2O3. Furthermore, CO2 temperature-programmed desorption revealed that the catalyst was strongly basic. These unique structural and electronic characteristics are considered to synergistically accelerate the rate-determining step of NH3 synthesis, cleavage of the N[triple bond, length as m-dash]N bond. We expect that the use of this catalyst will be a starting point for achieving efficient ammonia synthesis.

11.
Phys Chem Chem Phys ; 18(24): 16076-9, 2016 Jun 28.
Article in English | MEDLINE | ID: mdl-27198824

ABSTRACT

Organically modified titania having a metal catalyst (OMTC), 2,3-dihydroxynaphthalene-modified titania having palladium metal, successfully worked as a hydrogen-transfer (C[double bond, length as m-dash]C hydrogenation) photocatalyst in the presence of triethanolamine as the hydrogen source under visible light irradiation and hydrogen-free conditions.

12.
Chem Commun (Camb) ; 50(35): 4558-60, 2014 May 07.
Article in English | MEDLINE | ID: mdl-24668000

ABSTRACT

(2,3-Epoxypropyl)benzene was chemoselectively reduced to allylbenzene along with formation of ketones in alcoholic suspensions of a silver-loaded titanium(iv) oxide photocatalyst at room temperature under atmospheric pressure without the use of reducing gases, and various epoxides were also reduced to the corresponding alkenes.

13.
Chem Commun (Camb) ; 49(93): 10911-3, 2013 Dec 04.
Article in English | MEDLINE | ID: mdl-24129580

ABSTRACT

Benzonitrile (PhCN) was successfully reduced to benzyl amine in acidic aqueous suspensions of a palladium (Pd)-loaded titanium(IV) oxide (TiO2) photocatalyst in the presence of oxalic acid as a hole scavenger, although the reduction potential of PhCN is believed to be much higher than the potential of the conduction band (CB) of TiO2, indicating that a Pd co-catalyst strongly contributes to PhCN reduction and that the applicability of photocatalytic reduction is not limited by the CB position of semiconductor photocatalysts.

14.
Chem Commun (Camb) ; 49(25): 2551-3, 2013 Mar 28.
Article in English | MEDLINE | ID: mdl-23422929

ABSTRACT

A functionalized plasmonic Au/TiO2 photocatalyst with an Ag co-catalyst was successfully prepared by the combination of two types of photodeposition methods, and it quantitatively converted nitrobenzene and 2-propanol to aniline and acetone under irradiation of visible light.

15.
Chem Commun (Camb) ; 48(36): 4356-8, 2012 May 07.
Article in English | MEDLINE | ID: mdl-22451072

ABSTRACT

m-Nitrovinylbenzene was chemoselectively reduced to m-aminovinylbenzene in a suspension of a TiO(2) photocatalyst in the presence of a hole scavenger at room temperature under atmospheric pressure without the use of a precious metal or reducing gas, and nitrobenzenes having other reducible groups were also chemoselectively reduced to corresponding aminobenzenes.

16.
Phys Chem Chem Phys ; 13(11): 5114-9, 2011 Mar 21.
Article in English | MEDLINE | ID: mdl-21298128

ABSTRACT

Photocatalytic reduction of nitrobenzenes to corresponding aminobenzenes in aqueous suspensions of titanium(IV) oxide (TiO(2)) containing hole scavengers under various conditions was examined. In photocatalytic reduction of m-nitrobenzenesulfonic acid (m-NBS) in the presence of formic acid (FA) under deaerated conditions, m-aminobenzenesulfonic acid (m-ABS) was produced almost quantitatively in acidic suspensions and high efficiency (>99%) in FA utilization as a hole scavenger was achieved. No re-oxidation of m-ABS occurred in acidic conditions both in the presence and absence of FA. The high yield of m-ABS was explained by strong ability of FA as a hole scavenger and possible repulsion of the reduced functional group (ammonium group, -NH(3)(+)) from the protonated, i.e., positively charged TiO(2) surface in acidic suspensions avoiding re-oxidation of m-ABS. Using TiO(2) samples of various physical properties, which had been synthesized by a solvothermal method and post-calcination at various temperatures, effects of physical properties of the TiO(2) samples on m-ABS yield were also investigated. A linear correlation between the amount of m-NBS adsorbed and the m-ABS yield was observed, suggesting that ability of TiO(2) for m-NBS adsorption is one of the key factors for effective photocatalytic reduction of m-NBS to m-ABS. This photocatalytic system can be applied for reduction of aminonitrobenzenes to corresponding diaminobenzenes (DAB) in the presence of oxalic acid as a hole scavenger. High yields of m-ABS and DAB were achieved even when the reactions were performed in the presence of oxygen.

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