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1.
Optom Vis Sci ; 100(10): 702-707, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37855831

ABSTRACT

SIGNIFICANCE: The Global Myopia Prevalence and International Levels of Education study models national trends in educational performance with myopia prevalence in children; it examines the association of near work with myopia in the form of an ecologic analysis and also discusses how this may relate to educational frameworks. PURPOSE: This study aimed to investigate the relationship between myopia prevalence and national educational performance. METHODS: The prevalence of myopia in the 15- to 19-year age group in 35 regions was obtained from a meta-analysis by Holden et al. (Ophthalmology 2016;123:1036-1042) and matched with educational performance quantified by the Organisation for Economic Cooperation and Development Programme for International Student Assessment (PISA) testing from 2000 to 2018. A generalized estimating equation was used to describe the relationship between PISA scores and myopia prevalence. Clustering effects of country and chronological year were accounted for in the analysis. Linear and nonlinear terms of PISA scores using lines of best fit were further explored. RESULTS: There is a significant positive relationship between Organisation for Economic Cooperation and Development PISA educational performance and myopia prevalence in teenagers with higher PISA scores correlating with higher myopia prevalence, even after accounting for chronological year (generalized estimating equation model: P = .001, .008, and .005 for math, science, and reading, respectively). Scatterplots with cubic and logistic fits indicated that PISA math showed the strongest relationship with myopia prevalence ( r2 = 0.64), followed by science ( r2 = 0.41) and reading ( r2 = 0.31). CONCLUSIONS: These results strongly suggest that educational achievement at a national level is associated with higher myopia prevalence. Programme for International Student Assessment scores are a significant driver of many countries' education policies, and countries that have a balance between high PISA scores and lower myopia prevalence may be good models of educational policies to address the myopia public health issue.


Subject(s)
Myopia , Adolescent , Humans , Educational Status , Myopia/epidemiology , Prevalence , Reading , Young Adult , Meta-Analysis as Topic
2.
Org Biomol Chem ; 18(47): 9611-9622, 2020 12 21.
Article in English | MEDLINE | ID: mdl-33020797

ABSTRACT

The ruthenium(ii)-catalyzed cross-coupling reaction between 2-aryl quinazolinones and activated aldehydes is described. This method enables the site-selective hydroxyalkylation under redox-neutral conditions. Moreover, this protocol provides a facile access to various tetracyclic isoindoloquinazolinones by using Cu(OAc)2 as an external oxidant via C-H addition and subsequent intramolecular cyclization. A wide substrate scope and a high level of chemoselectivity as well as broad functional group tolerance are observed.

3.
J Org Chem ; 85(11): 7014-7023, 2020 06 05.
Article in English | MEDLINE | ID: mdl-32275431

ABSTRACT

The preparation of phthalazinone derivatives is pivotal for their utilization as pharmaceutical agents and other entities. Herein, we report the phthalazinone-assisted carbon-nitrogen bond forming reaction using dioxazolones as robust amidation sources under Rh(III) catalysis. The broad functional group tolerance and complete site-selectivity are observed. Notably, a series of transformations of synthesized compounds into biologically relevant N-heterocycles demonstrates the applicability of the developed methodology.

4.
J Org Chem ; 85(4): 2520-2531, 2020 02 21.
Article in English | MEDLINE | ID: mdl-31904238

ABSTRACT

Ruthenium(II)-catalyzed C(sp2)-H functionalization of N-aryl phthalazinones with a range of aldehydes and activated ketone is described. Initial formation of hydroxyalkylated phthalazinones and subsequent Mitsunobu cyclization provided facile access to biologically relevant indazolophthalazinones. The utility of this method is highlighted by synthetic transformations into a series of potentially bioactive scaffolds.

5.
J Org Chem ; 84(4): 2307-2315, 2019 02 15.
Article in English | MEDLINE | ID: mdl-30525635

ABSTRACT

The facile synthesis of hydroxymethylated indole derivatives is crucial for their further development as pharmaceutical compounds and other synthetic purposes. Herein, we describe the ruthenium(II)-catalyzed hydroxymethylation of indolines and other N-heterocycles using paraformaldehyde as an abundant C1 feedstock. A wide substrate scope range and high levels of site selectivity as well as functional group tolerance were observed.

6.
Restor Dent Endod ; 38(2): 85-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23741711

ABSTRACT

When a patient with a fractured anterior tooth visits the clinic, clinician has to restore the tooth esthetically and quickly. For esthetic resin restoration, clinician can use 'Natural Layering technique' and an index for palatal wall may be needed. In this case report, we introduce pre-restoration index technique on a Class IV defect, in which a temporary filling material is used for easy restoration. Chair-side index fabrication for Class IV restoration is convenient and makes a single-visit treatment possible.

7.
J Endod ; 39(6): 795-800, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23683281

ABSTRACT

INTRODUCTION: The purpose of this study was to investigate whether in vitro stimulation of pulp cells leads to increased secretion of matrix metalloproteinases (MMPs) and, if so, to identify which MMPs are affected. METHODS: Cells cultured from dental pulp were stimulated with tumor necrosis factor-α (TNF-α) (10 ng/mL) for 24 hours, and lysates were analyzed with an antibody array (Bio-Rad Laboratories, Hercules, CA). The mRNA and protein levels of MMP-3, -10, and -13 were measured by real-time polymerase chain reaction (real-time PCR), enzyme-linked immunosorbent assay (ELISA), Western blot analysis, and zymography. In addition, tumor necrosis factor receptors in the pulp cells were assayed by flow cytometry. The ELISA and real-time PCR results were analyzed by paired t tests. RESULTS: The expression of MMP-3, -10, and -13 was up-regulated in the pulp cells after 24 hours of stimulation with TNF-α (10 ng/mL) as seen in the antibody array, real-time PCR, and ELISA results, but MMP-10 was not detected by Western blotting or casein zymography. Flow cytometry analysis showed that the majority of the pulp cells expressed tumor necrosis factor receptor 1. CONCLUSIONS: In regions of inflammation, TNF-α may initiate the degradation of dental connective tissue by activating MMP-3 and MMP-13. These proteins may play an important pathologic role in the inflammation of dental pulp.


Subject(s)
Dental Pulp/enzymology , Matrix Metalloproteinases/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Cell Culture Techniques , Cells, Cultured , Dental Pulp/cytology , Dental Pulp/drug effects , Humans , Matrix Metalloproteinase 10/analysis , Matrix Metalloproteinase 10/drug effects , Matrix Metalloproteinase 13/analysis , Matrix Metalloproteinase 13/drug effects , Matrix Metalloproteinase 3/analysis , Matrix Metalloproteinase 3/drug effects , Matrix Metalloproteinases/analysis , Receptors, Tumor Necrosis Factor, Type I/analysis , Time Factors , Up-Regulation
8.
Article in English | MEDLINE | ID: mdl-18276547

ABSTRACT

This paper investigates the effect of K(1.94)Zn(1.06)Ta(5.19)O(15) (KZT) addition on the sintering behavior and piezoelectric properties in lead free piezoelectric ceramics of (K(0.5)Na(0.5))NbO(3) (KNN). The apparent density of sintered KNN ceramics was increased with KZT addition, and a relative density of above 96.3% was obtained with the doping of over 0.5 mol% KZT. The maximum dielectric and piezoelectric properties of epsilon(T)(3)/epsilon(0) = 590, d(33) = 126 pC/N, k(p) = 0.42, and P(r) = 18 microC/cm(2) were obtained from 0.5 mol% KZT-doped KNN ceramics. A small amount of KZT (about 0.5 mol%) was effective for improving the sintering behavior and piezoelectric properties, but KZT addition exceeding 1.0 mol% was effective only for densification. A small amount of KZT was effective for densification of KNN ceramics by promoting K(5.75)Nb(10.8)O(30) liquid phase formation. However, even though KNN with 1.0 to approximately -2.0 mol% KZT had a relative density of >98.5%, the piezoelectric properties were inferior to those of 0.5 mol% KZT-doped KNN, presumably due to the smaller grain size and excess liquid phase of the KNN ceramics doped with higher amounts of KZT. It is believed that a small amount of KZT could be one of the suitable sintering aids to obtain highly dense KNN based piezoelectric.


Subject(s)
Acoustics/instrumentation , Ceramics/chemistry , Crystallization/methods , Lead/chemistry , Titanium/chemistry , Transducers , Zirconium/chemistry , Electric Impedance , Electrochemistry/instrumentation , Electrochemistry/methods , Equipment Design , Equipment Failure Analysis , Hot Temperature , Reproducibility of Results , Sensitivity and Specificity
9.
J Comput Chem ; 25(2): 169-78, 2004 Jan 30.
Article in English | MEDLINE | ID: mdl-14648616

ABSTRACT

The effect of thioamide substitution on the conformational stability of an azaglycine-containing peptide, For-AzaGly-NH2 (1), was investigated for the sake of finding possible applications by using ab initio and DFT methods. As model compounds, For-[psiCSNH]-AzaGly-NH2 (2), For-AzaGly-[psiCSNH]-NH2 (3), and For-[psiCSNH]-AzaGly-[psiCSNH]-NH2 (4) were used. Two-dimensional phi-psi potential energy surfaces (PESs) for 2-4 were calculated at the B3LYP/6-31G*//HF/6-31G* level in gas (epsilon = 1.0) and in water (epsilon = 78.4) by applying the isodensity polarizable continuum model (IPCM) method. On the basis of these PESs, the minimum energy conformations for 2-4 were characterized at the B3LYP level with 6-31G*, 6-311G**, and 6-31+G** basis sets. The remarkable structural effect of thioamide substitution for 2-4 is that beta-strand structure is observed as a global or local minimum. The minima of 2-4 are also compared with those for glycine and thioamide-containing glycine peptides. Our theoretical results demonstrate that compounds 2-4 would be used to design controllable secondary structures.


Subject(s)
Glycine/analogs & derivatives , Glycine/chemistry , Peptides/chemistry , Thioamides/chemistry , Hydrogen Bonding , Models, Molecular , Molecular Conformation , Protein Conformation , Thermodynamics
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