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1.
Int Ophthalmol ; 43(7): 2433-2445, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36877316

RESUMEN

PURPOSE: To assess the effectiveness of combined use of stereoscopic 3D video movies and part-time patching in treating older amblyopic children with poor response or compliance to traditional patching treatments and comparing this combined treatment with patching alone. METHODS: Thirty-two children aged 5-12 years with amblyopia associated with anisometropia, strabismus, or both were recruited in a randomized clinical trial. Eligible participants were assigned randomly to the combined and patching groups. Here, binocular treatment refers to using the Bangerter filter to blur the fellow eye and subsequently watching a close-up 3D movie with large parallax. The primary outcome was amblyopic eye (AE) best-corrected visual acuity (BCVA) improvement at six weeks. In addition, secondary outcomes included BCVA of AE improvement at three weeks and change of stereoacuity. RESULTS: Of 32 participants, mean (SD) age was 6.63 (1.46) years, and 19 (59%) were female. At 6 weeks, mean (SD) amblyopic eye VA improved by 0.17 ± 0.08 logMAR (2-sided 95% CI, 0.13 to 0.22; F = 57.2, p < 0.01) and 0.05 ± 0.04 logMAR (2-sided 95% CI, 0.05 to 0.09; F = 8.73, p = 0.01) in the combined and patching groups, respectively. The difference was statistically significant (mean difference, 0.13 logMAR [1.3 line]; 95% CI, 0.08-0.17 logMAR [0.8-1.7 lines]; t25 = 5.65, p < 0 .01). After treatment, only the combined group had significantly improved stereoacuity, such as binocular function score (median [interquartile range], 2.30 [2.23 to 2.68] vs. 1.69 [1.60 to 2.30] log arcsec; paired, z = -3.53, p < 0.01), and mean stereoacuity gain was 0.47 log arcsec (± 0.22). Changes in other types of stereoacuity were similar. CONCLUSION: Our laboratory-based binocular treatment strategy engaged a high level of compliance that led to a substantial gain in visual function after a short period of treatment for older amblyopic children having poor response or compliance to traditional patching treatments. Notably, the improving stereoacuity showed a greater advantage.


Asunto(s)
Ambliopía , Juegos de Video , Humanos , Niño , Femenino , Anciano , Masculino , Ambliopía/terapia , Resultado del Tratamiento , Estudios de Seguimiento , Visión Binocular/fisiología , Computadoras de Mano , Anteojos , Privación Sensorial
2.
Mol Med Rep ; 24(5)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34490478

RESUMEN

Age­related macular degeneration (AMD) is a global health problem. Lycium barbarum polysaccharide (LBP), a traditional Chinese herbal medicine, has been proven to be effective against several eye diseases. However, only a few studies have investigated the effectiveness of LBP for AMD. In the present study, the human retinal epithelial cell line, ARPE­19, was pretreated with LBP for 24 h before exposure to H2O2 (500 µM). Cell viability was assessed, and a series of oxidative and antioxidant indicators were evaluated to determine the influence of LBP on H2O2­triggered oxidative stress. The present study also determined the apoptosis status, as well as the expression levels of apoptotic proteins and nuclear factor erythroid 2­related factor 2 (Nrf2)/heme oxygenase­1 (HO­1) pathway proteins. The present study aimed to determine the protective role for LBP pretreatment and its underlying molecular mechanism. The results of the present study suggest that pretreatment of ARPE­19 cells with LBP exhibit high efficacy at reducing oxidative damage and inhibiting cell apoptosis. Furthermore, LBP may modulate the expression of proteins involved in the apoptotic pathway and activate the Nrf2 signaling pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Degeneración Macular/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Línea Celular , Hemo-Oxigenasa 1/metabolismo , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo
3.
Plant Cell Environ ; 41(1): 176-186, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28963730

RESUMEN

Volatile terpenoids produced in tea plants (Camellia sinensis) are airborne signals interacting against other ecosystem members, but also pleasant odorants of tea products. Transcription regulation (including transcript processing) is pivotal for plant volatile terpenoid production. In this study, a terpene synthase gene CsLIS/NES was recovered from tea plants (C. sinensis cv. "Long-Men Xiang"). CsLIS/NES transcription regulation resulted in 2 splicing forms: CsLIS/NES-1 and CsLIS/NES-2 lacking a 305 bp-fragment at N-terminus, both producing (E)-nerolidol and linalool in vitro. Transgenic tobacco studies and a gene-specific antisense oligo-deoxynucleotide suppression applied in tea leaves indicated that CsLIS/NES-1, localized in chloroplasts, acted as linalool synthase, whereas CsLIS/NES-2 localized in cytosol, functioned as a potential nerolidol synthase, but not linalool synthase. Expression patterns of the 2 transcript isoforms in tea were distinctly different and responded differentially to the application of stress signal molecule methyl jasmonate. Leaf expression of CsLIS/NES-1, but not CsLIS/NES-2, was significantly induced by methyl jasmonate. Our data indicated that distinct transcript splicing regulation patterns, together with subcellular compartmentation of CsLIS/NE-1 and CsLIS/NE-2 implemented the linalool biosynthesis regulation in tea plants in responding to endogenous and exogenous regulatory factors.


Asunto(s)
Camellia sinensis/genética , Monoterpenos/metabolismo , Proteínas de Plantas/metabolismo , Empalme del ARN/genética , Acetatos/farmacología , Monoterpenos Acíclicos , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Secuencia de Bases , Camellia sinensis/efectos de los fármacos , Camellia sinensis/metabolismo , Ciclopentanos/farmacología , Flores/efectos de los fármacos , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Oxilipinas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Empalme del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Sesquiterpenos/metabolismo , Fracciones Subcelulares/metabolismo , Terpenos/metabolismo , Nicotiana/genética
4.
Sci Rep ; 7: 45062, 2017 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-28332598

RESUMEN

In this study, shade-induced conversion from a young pale/yellow leaf phenotype to a green leaf phenotype was studied using metabolic and transcriptomic profiling and the albino cultivar 'Yu-Jin-Xiang' ('YJX') of Camellia sinensis for a better understanding of mechanisms underlying the phenotype shift and the altered catechin and theanine production. Shaded leaf greening resulted from an increase in leaf chlorophyll and carotenoid abundance and chloroplast development. A total of 1,196 differentially expressed genes (DEGs) were identified between the 'YJX' pale and shaded green leaves, and these DEGs affected 'chloroplast organization' and 'response to high light' besides many other biological processes and pathways. Metabolic flux redirection and transcriptomic reprogramming were found in flavonoid and carotenoid pathways of the 'YJX' pale leaves and shaded green leaves to different extents compared to the green cultivar 'Shu-Cha-Zao'. Enhanced production of the antioxidant quercetin rather than catechin biosynthesis was correlated positively with the enhanced transcription of FLAVONOL SYNTHASE and FLAVANONE/FLAVONOL HYDROXYLASES leading to quercetin accumulation and negatively correlated to suppressed LEUCOANTHOCYANIDIN REDUCTASE, ANTHOCYANIDIN REDUCTASE and SYNTHASE leading to catechin biosynthesis. The altered levels of quercetin and catechins in 'YJX' will impact on its tea flavor and health benefits.


Asunto(s)
Camellia sinensis/genética , Camellia sinensis/metabolismo , Catequina/biosíntesis , Metabolismo Energético/genética , Transcriptoma , Camellia sinensis/ultraestructura , Reprogramación Celular , Cloroplastos/genética , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Biología Computacional/métodos , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Glutamatos/biosíntesis , Redes y Vías Metabólicas , Anotación de Secuencia Molecular , Fenotipo , Pigmentación , Hojas de la Planta , Reproducibilidad de los Resultados
5.
Food Chem ; 212: 739-48, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27374591

RESUMEN

Flavour determinants in tea infusions and their changes during manufacturing processes were studied using Camellia sinensis cultivars 'Bai-Sang Cha' ('BAS') possessing significant floral scents and 'Fuding-Dabai Cha' ('FUD') with common green tea odour. Metabolite profiling based on odour activity threshold revealed that 'BAS' contained higher levels of the active odorants ß-ionone, linalool and its two oxides, geraniol, epoxylinalool, decanal and taste determinant catechins than 'FUD' (p<0.05). Enhanced transcription of some terpenoid and catechin biosynthetic genes in 'BAS' suggested genetically enhanced production of those flavour compounds. Due to manufacturing processes, the levels of linalool and geraniol decreased whereas those of ß-ionone, linalool oxides, indole and cis-jasmone increased. Compared with pan-fire treatment, steam treatment reduced the levels of catechins and proportion of geraniol, linalool and its derivatives, consequently, reducing catechin-related astringency and monoterpenol-related floral scent. Our study suggests that flavour determinant targeted modulation could be made through genotype and manufacturing improvements.


Asunto(s)
Camellia sinensis/química , Catequina/metabolismo , Aromatizantes/química , Monoterpenos/metabolismo , Odorantes/análisis , Extractos Vegetales/química , Té/química , Monoterpenos Acíclicos , Química Farmacéutica , Gusto
6.
Food Chem ; 155: 98-104, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24594160

RESUMEN

Albino tea has received increased attention due to its brisk flavour. To identify changes in the key chemical constituents conveying important qualities to albino tea, the metabolite profiles of four albino cultivars and one green tea cultivar were analysed. Compared to the green tea control, significantly decreased contents of chlorophyll (Chl) (p<0.01), total carotenoids (p<0.05), caffeine (p<0.01), and total catechins (p<0.05) were found in albino tea leaves with a few exceptions, whereas increases were noted in the Chl a/b ratio and the contents of both zeaxanthin and free amino acids, including theanine. Multivariate analysis identified catechins and carotenoids as the most important contributors to the metabolic profile variance between the albino and green tea cultivars. High levels of amino acids, along with low levels of chlorophylls, catechins and caffeine, contribute to the qualities of albino tea, which include reduced astringency and bitterness, along with a strong umami taste.


Asunto(s)
Camellia sinensis/química , Extractos Vegetales/análisis , Hojas de la Planta/química , Aminoácidos/análisis , Aminoácidos/metabolismo , Cafeína/análisis , Cafeína/metabolismo , Camellia sinensis/clasificación , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Catequina/análisis , Catequina/metabolismo , Clorofila/análisis , Clorofila/metabolismo , Clorofila A , Análisis Discriminante , Humanos , Extractos Vegetales/metabolismo , Hojas de la Planta/clasificación , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Control de Calidad , Gusto , Té/química , Xantófilas/análisis , Xantófilas/metabolismo , Zeaxantinas
7.
BMC Plant Biol ; 12: 169, 2012 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-22989211

RESUMEN

BACKGROUND: The Arabidopsis microRNA156 (miR156) regulates 11 members of the SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL) family by base pairing to complementary target mRNAs. Each SPL gene further regulates a set of other genes; thus, miR156 controls numerous genes through a complex gene regulation network. Increased axillary branching occurs in transgenic Arabidopsis overexpressing miR156b, similar to that observed in loss-of-function max3 and max4 mutants with lesions in carotenoid cleavage dioxygenases. Arabidopsis miR156b was found to enhance carotenoid levels and reproductive shoot branching when expressed in Brassica napus, suggesting a link between miR156b expression and carotenoid metabolism. However, details of the miR156 regulatory network of SPL genes related to carotenoid metabolism are not known. RESULTS: In this study, an Arabidopsis T-DNA enhancer mutant, sk156, was identified due to its altered branching and trichome morphology and increased seed carotenoid levels compared to wild type (WT) ecovar Columbia. Enhanced miR156b expression due to the 35S enhancers present on the T-DNA insert was responsible for these phenotypes. Constitutive and leaf primodium-specific expression of a miR156-insensitive (mutated) SPL15 (SPL15m) largely restored WT seed carotenoid levels and plant morphology when expressed in sk156. The Arabidopsis native miR156-sensitive SPL15 (SPL15n) and SPL15m driven by a native SPL15 promoter did not restore the WT phenotype in sk156. Our findings suggest that SPL15 function is somewhat redundant with other SPL family members, which collectively affect plant phenotypes. Moreover, substantially decreased miR156b transcript levels in sk156 expressing SPL15m, together with the presence of multiple repeats of SPL-binding GTAC core sequence close to the miR156b transcription start site, suggested feedback regulation of miR156b expression by SPL15. This was supported by the demonstration of specific in vitro interaction between DNA-binding SBP domain of SPL15 and the proximal promoter sequence of miR156b. CONCLUSIONS: Enhanced miR156b expression in sk156 leads to the mutant phenotype including carotenoid levels in the seed through suppression of SPL15 and other SPL target genes. Moreover, SPL15 has a regulatory role not only for downstream components, but also for its own upstream regulator miR156b.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes/genética , MicroARNs/metabolismo , Mutación/genética , Factores de Transcripción/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Secuencia de Bases , Carotenoides/metabolismo , ADN Bacteriano/genética , Regulación hacia Abajo/genética , Genes de Plantas/genética , Datos de Secuencia Molecular , Mutagénesis Insercional/genética , Motivos de Nucleótidos/genética , Fenotipo , Tallos de la Planta/anatomía & histología , Tallos de la Planta/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Estructura Terciaria de Proteína , Reproducibilidad de los Resultados , Supresión Genética , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Transcripción Genética , Transgenes
8.
Planta Med ; 77(7): 765-70, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21104608

RESUMEN

Flavonoids belong to a group of plant natural products with variable phenolic structures and play important roles in protection against biotic and abiotic stress. Fenugreek (Trigonella foenum-graecum L.) seeds and stems contain flavonol glycosides and isoflavone derivatives. Up to now, the molecular features of fenugreek flavonoid biosynthesis have not been characterized. Here we present cloning of a cDNA encoding a chalcone isomerase (namely TFGCHI-1) from the leaves of T. foenum-graecum which convert chalcones to flavanones in vitro. Transformation of Arabidopsis loss-of-function TT5 (CHI) mutant with a TFGCHI-1 cDNA complemented TT5 and produced higher levels of flavonol glycosides than wild-type Col-0.


Asunto(s)
Liasas Intramoleculares/genética , Proteínas de Plantas/genética , Trigonella/enzimología , Secuencia de Aminoácidos , Arabidopsis/genética , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Flavonoides/biosíntesis , Vectores Genéticos/genética , Glicósidos/biosíntesis , Liasas Intramoleculares/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/metabolismo , Semillas/química , Trigonella/genética
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