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1.
Asia Pac J Ophthalmol (Phila) ; 12(4): 370-376, 2023.
Article in English | MEDLINE | ID: mdl-37523428

ABSTRACT

PURPOSE: The purpose of this study was to assess the dose-response effects of low-dose atropine on myopia progression and safety in pediatric subjects with mild-to-moderate myopia. METHODS: This phase II, randomized, double-masked, placebo-controlled study compared the efficacy and safety of atropine 0.0025%, 0.005%, and 0.01% with placebo in 99 children, aged 6-11 years, with mild-to-moderate myopia. Subjects received 1 drop in each eye at bedtime. The primary efficacy endpoint was change in spherical equivalent (SE), while secondary endpoints included changes in axial length (AL) and near logMAR (logarithm of the minimum angle of resolution) visual acuity and adverse effects. RESULTS: The mean±SD changes in SE from baseline to 12 months in the placebo and atropine 0.0025%, 0.005%, and 0.01% groups were -0.55±0.471, -0.55±0.337, -0.33±0.473, and -0.39±0.519 D, respectively. The least squares mean differences (atropine-placebo) in the atropine 0.0025%, 0.005%, and 0.01% groups were 0.11 D ( P =0.246), 0.23 D ( P =0.009), and 0.25 D ( P =0.006), respectively. Compared with placebo, the mean change in AL was significantly greater for atropine 0.005% (-0.09 mm, P =0.012) and 0.01% (-0.10 mm, P =0.003). There were no significant changes in near visual acuity in any of the treatment groups. The most common ocular adverse events were pruritus and blurred vision, each occurring in 4 (5.5%) atropine-treated children. Changes in mean pupil size and amplitude of accommodation were minimal. CONCLUSIONS: Atropine doses of 0.005% and 0.01% effectively reduced myopia progression in children but no effect was noted with 0.0025%. All doses of atropine were safe and well tolerated.


Subject(s)
Atropine , Myopia , Humans , Child , Administration, Topical , Ophthalmic Solutions/adverse effects , Atropine/therapeutic use , Myopia/drug therapy , Refraction, Ocular , Axial Length, Eye , Disease Progression
2.
J Chromatogr A ; 1151(1-2): 74-81, 2007 Jun 01.
Article in English | MEDLINE | ID: mdl-17399729

ABSTRACT

High-speed counter-current chromatography (HSCCC) using the three-phase solvent system n-hexane-methyl acetate-acetonitrile-water at a volume ratio of 4:4:3:4 was applied to the comprehensive separation of secondary metabolites in several natural product extracts. A wide variety of secondary metabolites in each natural product was effectively extracted with the three-phase solvent system, and the filtered extract was directly submitted to the HSCCC separation using the same three-phase system. In the HSCCC profiles of crude natural drugs listed in the Japanese Pharmacopoeia, several physiologically active compounds were clearly separated from other components in the extracts. The HSCCC profiles of several tea products, each manufactured by a different process, clearly showed their compositional difference in main compounds such as catechins, caffeine, and pigments. These HSCCC profiles also provide useful information about hydrophobic diversity of whole components present in each natural product.


Subject(s)
Countercurrent Distribution/methods , Plant Extracts/chemistry , Solvents/chemistry , Caffeine/analysis , Capsicum/chemistry , Catechin/analysis , Zingiber officinale/chemistry , Plant Extracts/isolation & purification , Reproducibility of Results , Tea/chemistry
3.
J Chromatogr A ; 1143(1-2): 153-61, 2007 Mar 02.
Article in English | MEDLINE | ID: mdl-17223120

ABSTRACT

A novel method was developed for the separation of proanthocyanidins (PAs; oligomeric flavan-3-ols) by hydrophilic interaction chromatography (HILIC) using an amide-silica column eluting with an aqueous acetonitrile mobile phase. The best separation was achieved with a linear gradient elution of acetonitrile-water at ratios of 9:1 to 5:5 (v/v) for 60 min at a flow rate of 1.0 ml/min. Under these HPLC conditions, a mixture of natural oligomeric PAs (from apple) was separated according to degree of polymerization (DP) up to decamers. The DP of each separated oligomer was confirmed by LC/electrospray ionization MS. In further HILIC separation studies of 15 different flavan-3-ol and oligomeric PA (up to pentamer) standards with an isocratic elution of acetonitrile-water (84:16), a high correlation was observed between the logarithm of retention factors (log k) and the number of hydroxyl groups in their structures. The coefficient of this correlation (r2=0.9501) was larger than the coefficient (r2=0.7949) obtained from the correlation between log k and log P(o/w) values. These data reveal that two effects, i.e. hydrogen bonding between the carbamoyl terminal on the column and the hydroxyl group of solute oligomer and hydrophilicity based on the high-order structure of oligomeric PAs, corporately contribute to the separation, but the hydrogen bonding effect is predominant in our HILIC separation mode.


Subject(s)
Chromatography, High Pressure Liquid/methods , Proanthocyanidins/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
4.
J Chromatogr A ; 1133(1-2): 119-25, 2006 Nov 10.
Article in English | MEDLINE | ID: mdl-16920128

ABSTRACT

Three-phase solvent systems were efficiently utilized for high-speed counter-current chromatography (HSCCC) to separate multiple components with a wide range of hydrophobicity. The compositions of three-phase systems were optimized according to their physical parameters such as volume ratio, viscosity and specific gravity of upper (UP), middle (MP) and lower (LP) phases. The three-phase systems composed of n-hexane-methyl acetate-acetonitrile-water (4:4:3:4, v/v/v/v) was selected for HSCCC separation of a mixture of 15 standard compounds with a wide range in hydrophobicity from beta-carotene to tryptophan. The separation was initiated by filling the column with a mixture of MP and LP both as a stationary phase followed by elution with UP to separate the hydrophobic compounds. Then the mobile phase was switched to MP to elute the moderately hydrophobic compounds, and finally the polar compounds still retained in the column were fractionated by eluting the column with LP. The system successfully resolved all 15 compounds in one-step operation in 70 min.


Subject(s)
Chromatography, Liquid/methods , Countercurrent Distribution/methods , Organic Chemicals/analysis , Solvents/chemistry , Molecular Structure , Organic Chemicals/chemistry
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