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1.
Cont Lens Anterior Eye ; 47(2): 102106, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38105172

RESUMEN

PURPOSE: RigidCare is an electrolysis-based device that recently obtained approval from the US's FDA to sterilise microorganisms and remove proteins for orthokeratology (O-K) lenses. The study was conducted to investigate the device's performance in varied clinical circumstances. METHODS: Trial lenses and private lenses were employed by O-K lens wearers from five hospitals for an evaluation of disinfection and sterilisation and an assessment of protein removal, respectively. Menicon multipurpose solution and protein remover were selected for use with the control group. Following the instructions, pre-cleaning lens samples, post-cleaning lens samples and residual solution samples of trial lenses of the experimental and control groups were collected for microorganism examinations by an experienced third-party testing organisation. The levels of protein deposition for these two approaches were rated by senior O-K experts. Categorical variables were analysed using statistical tests, such as the chi-squared test and Fisher's exact test. RESULTS: The microbial positive rate detected from the pre-cleaning and post-cleaning lens samples and the residual solution of the trial lenses for the experimental and control group was 4/76 vs 1/74 (P = 0.37), 1/76 vs 0/74 (P = 1.00) and 0/76 vs 8/74 (P = 0.006), respectively. Following protein removal, the experimental group exhibited a significantly higher overall proportion of lenses rated as 'clean' or with a 'mild deposit' (96.4 %, 79/82) compared to the control group (85.7 %, 66/77), with a significant difference (P < 0.05). CONCLUSION: This multi-center study demonstrated that RigidCare exhibited superior efficacy in disinfection, sterilisation and protein removal as compared to Menicon multipurpose solution and protein remover.


Asunto(s)
Lentes de Contacto Hidrofílicos , Cristalino , Humanos , Desinfección , Soluciones para Lentes de Contacto/farmacología
2.
Nano Lett ; 21(6): 2347-2355, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33705149

RESUMEN

Graphene-based one-dimensional macroscopic assemblies (GBOMAs) have attracted great attention and extensive efforts have been devoted to enabling great progress. However, their applications are still restricted to less functionalized electronics, and the superior potentials remain scarce. Herein, inspired by natural scallion structure, a novel strategy was introduced to effectively improve battery performances through the mesoscale scallion-like wrapping of graphene. The obtained RGO/Ag-Li anodes demonstrated an ultralow overpotential of ∼11.3 mV for 1800 h at 1 mA cm-2 in carbonate electrolytes, which is superior to those of the most previous reports. Besides, this strategy can also be further expanded to the high mass loading of various cathode nanomaterials, and the resulting RGO/LiFePO4 cathodes exhibited remarkable rate performance and cycle stability. This work opens a new avenue to explore and broaden the applications of GBOMAs as scaffolds in fabricating full lithium batteries via maximizing their advantages derived from the unique structure and properties.

3.
BMC Ophthalmol ; 15: 73, 2015 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-26152123

RESUMEN

BACKGROUND: Due to its high prevalence and associated sight-threatening pathologies, myopia has emerged as a major health issue in East Asia. The purpose was to test the impact on myopia development of a school-based intervention program aimed at increasing the time student spent outdoors. METHODS: A total of 3051 students of two primary (grades 1-5, aged 6-11) and two junior high schools (grades 7-8, aged 12-14) in both urban and rural Northeast China were enrolled. The intervention group (n = 1735) unlike the control group (n = 1316) was allowed two additional 20-min recess programs outside the classroom. A detailed questionnaire was administered to parents and children. Uncorrected visual acuity (UCVA) was measured using an E Standard Logarithm Vision Acuity Chart (GB11533-2011) at baseline, 6-month and 1-year intervals. A random subsample (n = 391) participated in the clinic visits and underwent cycloplegia at the beginning and after 1 year. RESULTS: The mean UCVA for the entire intervention group was significantly better than the entire control group after 1 year (P < 0.001). In the subgroup study, new onset of myopia and changes in refractive error towards myopia were direction during the study period was significantly lower in the intervention group than in the control group (3.70 % vs. 8.50 %, P = 0.048; -0.10 ± 0.65 D/year vs. -0.27 ± 0.52 D/year, P = 0.005). Changes in axial length and IOP were also significantly lower following the intervention group (0.16 ± 0.30 mm/year vs. 0.21 ± 0.21 mm/year, P = 0.034; -0.05 ± 2.78 mmHg/year vs. 0.67 ± 2.21 mmHg/year, P = 0.006). CONCLUSIONS: Increasing outdoor activities prevented myopia onset and development, as well as axial growth and elevated IOP in children. TRIAL REGISTRATION: Current controlled trials NCT02271373.


Asunto(s)
Actividades Recreativas , Miopía/diagnóstico , Miopía/prevención & control , Adolescente , Longitud Axial del Ojo/fisiopatología , Niño , China/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Miopía/epidemiología , Población Rural/estadística & datos numéricos , Encuestas y Cuestionarios , Población Urbana/estadística & datos numéricos , Agudeza Visual/fisiología
4.
Ophthalmic Physiol Opt ; 35(3): 252-62, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25913873

RESUMEN

PURPOSE: To determine whether elevated light levels in classrooms in rural areas can protect school-age children from myopia onset or myopia progression. METHODS: A total of 317 subjects from 1713 eligible students aged six to 14 in four schools located in northeast China participated in the study. Students received a comprehensive eye examination including cycloplegic refraction and ocular biometry, which included axial length (AL), anterior chamber depth (ACD), and corneal curvature (CC) measurement, and completed a questionnaire. The intervention arm included 178 students in two schools with rebuilt elevated lighting systems and the control arm included 139 students in which lighting systems were unchanged. Results for the two arms were compared with a Wilcoxon rank sum test, a chi-squared test or a t-test, as appropriate. Factors that might help explain any differences were explored with multivariate linear regression analysis. RESULTS: The median average illuminance of blackboards and desks and uniformity of desk lighting were significantly improved, however, the uniformity of blackboard lighting declined after intervention. At baseline, the mean refraction, AL, CC, ACD and myopia prevalence between the two arms were not significantly different. After 1 year, compared with the control arm the intervention arm had a lower incidence of new myopia onset (4% vs 10%; p = 0.029), a smaller decrease in refractive error among no myopic subjects (-0.25 dioptre [D] vs -0.47 D; p = 0.001), and shorter axial growth for both non-myopic (0.13 vs 0.18 mm; p = 0.023) and myopic subjects (0.20 vs 0.27 mm; p = 0.0001). Multivariate linear regression analysis showed the intervention program, lower hyperopic baseline refraction, lower father's education level, longer time sleeping and less time in screen-viewing activities were associated with less refractive shift in the direction of myopia in non-myopic children. For myopic subjects, myopia progression was significantly associated with family income only. The intervention program and older age had a protective effect on axial growth for both myopic and non-myopic subjects. The father's education level and sleep duration were significantly associated with axial growth in non-myopic children. CONCLUSIONS: Elevated light levels in classrooms have a significant effect on myopia onset, decreases in refraction, and axial growth; if the findings of lighting intervention are reproduced in future studies, the ambient light levels in schools should be improved.


Asunto(s)
Iluminación/métodos , Miopía/prevención & control , Instituciones Académicas , Adolescente , Biometría/métodos , Niño , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Miopía/patología , Miopía/fisiopatología , Estudios Prospectivos , Refracción Ocular/fisiología , Salud Rural , Factores Socioeconómicos , Agudeza Visual/fisiología
5.
Int J Ophthalmol ; 3(4): 299-303, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22553578

RESUMEN

AIM: To investigate 5-hydroxytryptamine (5-HT) function and 5-HT receptor 2A (5-HT2A) mRNA expression in the formation of lens-induced myopia (LIM). METHODS: Lens-induced myopia construction method was applied to generate myopia on guinea pig right eye (LIM eye). RESULTS: LIM eyes formed significant myopia with longer axial length. 5-HT level in retina, choroids and sclera from LIM eyes was significantly higher than that in control group. 5-HT2A mRNA expression was also significantly up-regulated. CONCLUSION: Refraction lens could induce myopia in guinea pig and 5-HT may play an important role in the formation of myopia by binding with 5-HT2A receptor.

6.
Dev Dyn ; 237(3): 640-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18265023

RESUMEN

The interspecies somatic cell nuclear transfer (iSCNT) technique for therapeutic cloning gives great promise for treatment of many human diseases. However, the incomplete nuclear reprogramming and the low blastocyst rate of iSCNT are still big problems. Herein, we observed the effect of TSA on the development of rabbit-rabbit intraspecies and rabbit-human interspecies cloned embryos. After treatment with TSA for 6 hr during activation, we found that the blastocyst rate of rabbit-rabbit cloned embryos was more than two times higher than that of untreated embryos; however, the blastocyst rate of TSA-treated rabbit-human interspecies cloned embryos decreased. We also found evident time-dependent histone deacetylation-reacetylation changes in rabbit-rabbit cloned embryos, but not in rabbit-human cloned embryos from fusion to 6 hr after activation. Our results suggest that TSA-treatment does not improve blastocyst development of rabbit-human iSCNT embryos and that abnormal histone deacetylation-reacetylation changes in iSCNT embryos may account for their poor blastocyst development.


Asunto(s)
Blastocisto/fisiología , Clonación de Organismos , Ácidos Hidroxámicos/farmacología , Acetilación , Animales , Desarrollo Embrionario , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Histonas/metabolismo , Humanos , Técnicas de Transferencia Nuclear , Oocitos/citología , Oocitos/metabolismo , Conejos
7.
Zygote ; 16(1): 21-7, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18221578

RESUMEN

Early studies have shown that some mouse cumulus-oocyte complexes (COCs) stored at room temperature for 24 h still retained full developmental potential. In this study, we stored denuded mouse oocytes (DOs) at room temperature (25 degrees C) for 24 h and activated these oocytes with 10 mM SrCl2 or fertilized the oocytes by IVF. We found that nearly half of the DOs stored at room temperature for 1 day can be fertilized normally by IVF and that two foster mothers gave birth to seven pups. Embryos from stored oocytes were cultured in CZB medium with or without 1 microg/ml 17beta-estradiol (E2). The numbers of embryo that developed to morula/blastocyst stage after parthenogenetic activation and IVF were significantly increased when E2 was added to the culture (p<0.05). These results suggest that E2 might improve mouse embryo development in vitro. The birth of seven agouti pups and their healthy growth indicated that the storage of DOs at room temperature for 1 day may be a practical procedure for mammalian reproduction.


Asunto(s)
Fertilización In Vitro , Oocitos/fisiología , Folículo Ovárico/fisiología , Animales , Blastocisto/fisiología , Técnicas de Cultivo de Embriones , Transferencia de Embrión , Femenino , Cuidados en el Hogar de Adopción , Masculino , Ratones , Ratones Endogámicos C57BL , Partenogénesis/fisiología , Embarazo , Espermatozoides/fisiología
8.
Reproduction ; 134(6): 731-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18042630

RESUMEN

This study was carried out to investigate the contributions of chromosomes to spindle assembly in mouse oocytes. We generated two groups of cytoplasts (holo- and hemi-cytoplasts) by enucleation of germinal vesicle (GV), metaphase I (MI), and metaphase II (MII) oocytes using micromanipulation technology. After in vitro culture for 18 h, spindles with different shapes (bi-, mono-, or multipolar) formed in most of these cytoplasts except in hemi-GV cytoplasts. Two or more spindles were observed in most of holo-GV, holo-MI, and holo-MII cytoplasts (76.1, 77.0, and 83.7% respectively). However, the proportions of hemi-MI and hemi-MII cytoplasts with multiple sets of spindles decreased to 17.6 and 20.7% respectively. A single bipolar spindle was observed in each sham-operated oocyte generated by removing different volumes of cytoplasm from the oocytes and keeping nuclei intact. Localization of gamma-tubulin showed that microtubule organizing centers (MTOCs) were dispersed at each pole of the multiple sets of spindles formed in holo-cytoplasts. However, most of the MTOCs aggregated at the two poles of the bipolar spindle in sham-operated oocytes. Our results demonstrate that chromosomes are not essential for initiating spindle assembly but for directing distinct MTOCs to aggregate to form a bipolar spindle. Some factors of undetermined nature may pre-exist in an inactive form in GV-stage ooplasm, serving as initiators of spindle assembly upon their activation. Moreover, GV materials released into the cytoplasm may facilitate spindle assembly in normal meiotic maturation.


Asunto(s)
Meiosis/fisiología , Oocitos/citología , Huso Acromático/fisiología , Animales , Biomarcadores/análisis , Núcleo Celular , Cromosomas de los Mamíferos/fisiología , Citoplasma/química , Citoplasma/ultraestructura , Femenino , Metafase , Ratones , Micromanipulación , Centro Organizador de los Microtúbulos/ultraestructura , Oocitos/química , Huso Acromático/ultraestructura , Coloración y Etiquetado , Tubulina (Proteína)/análisis
9.
Biol Reprod ; 77(4): 666-70, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17582009

RESUMEN

Because some animals and human beings potentially engage in sexual activity at any day of the menstrual cycle, this may cause fertilization of postovulatory aged oocytes, which result in decreased potential of embryo development and longevity of offspring. To investigate the involvement of histone acetylation in the function of postovulatory aging, we examined the changes of histone acetylation by immunostaining with specific antibodies against various acetylated lysines on histones H3 and H4. We found that the acetylation levels of lysine 14 on histone H3 and lysines 8 and 12 on histone H4 in mouse oocytes were gradually increased during in vivo and in vitro postovulatory aging. Furthermore, the acetylation levels on these sites were markedly decreased or increased when the process of postovulatory aging was artificially delayed or accelerated, respectively. These results indicated that the gradual acetylation on some lysines of histones H3 and H4 is one of the phenomena in the process of postovulatory aging. Moreover, raising the level of histone acetylation by trichostatin A can accelerate the progression of postovulatory aging, suggesting that alteration of the acetylation on histones H3 and H4 can affect the progression of postovulatory aging in mouse oocytes.


Asunto(s)
Senescencia Celular , Histonas/metabolismo , Fase Luteínica/metabolismo , Oocitos/metabolismo , Ovulación , Acetilación/efectos de los fármacos , Adenina/análogos & derivados , Adenina/farmacología , Animales , Cafeína/farmacología , Femenino , Ácidos Hidroxámicos/farmacología , Ratones , Ratones Endogámicos , Oocitos/efectos de los fármacos , Inhibidores de Fosfodiesterasa/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología
10.
Theriogenology ; 68(4): 640-5, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17576000

RESUMEN

The objective was to investigate, using a mouse model, the effects of caffeine on the number of ovulated oocytes, the rate of oocyte maturation, the susceptibility of oocytes to activating stimuli, spindle morphology, and distribution of cortical granules (CGs). Mice were given caffeine (150 mg/kg body weight ip) at various times relative to hCG (-2, 0, and +2h); in an in vitro study, 1, 5 or 10 mM caffeine was added to the maturation culture. Caffeine had no effect on the quality of oocytes in vivo maturation, but caffeine was detrimental to the quality of oocytes matured in vitro. Further studies are needed to determine caffeine concentration in follicles relative to that in culture medium.


Asunto(s)
Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Oocitos/efectos de los fármacos , Superovulación/efectos de los fármacos , Animales , Femenino , Fluoresceína-5-Isotiocianato/química , Colorantes Fluorescentes/química , Ratones , Microscopía Confocal , Oocitos/crecimiento & desarrollo , Oocitos/ultraestructura , Propidio/química , Huso Acromático/efectos de los fármacos , Huso Acromático/fisiología , Huso Acromático/ultraestructura , Superovulación/fisiología
11.
Biochem Biophys Res Commun ; 354(1): 77-83, 2007 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-17210126

RESUMEN

Histone modifications are thought to play important roles in various cellular functions. In this article, the distribution patterns of acetylation on histone H4, methylation on histone H3 lysine 9, and phosphorylation on histone H3 serine 10 were examined in in vivo and in vitro fertilization (IVF) preimplantation mouse embryos by using indirect immunofluorescence and scanning confocal microscopy. We desired to know whether the IVF, which has been widely used as a routine assisted reproductive technology in animal and human, was safe at the epigenetic level. As results, we found that there was no difference in these histone modification patterns in in vivo and IVF mouse embryos from zygote to blastocyst stage. Moreover, these histone modifications had different distributions at all examined stages, but they were consistent with the mouse embryo developmental stages.


Asunto(s)
Metilación de ADN , Embrión de Mamíferos/metabolismo , Fertilización/fisiología , Histonas/metabolismo , Acetilación , Animales , Epigénesis Genética/fisiología , Femenino , Fertilización In Vitro , Ratones , Fosforilación , Embarazo , Distribución Tisular
12.
Wei Sheng Yan Jiu ; 34(2): 191-3, 2005 Mar.
Artículo en Chino | MEDLINE | ID: mdl-15952661

RESUMEN

OBJECTIVE: To observe the effects of Icariin on ovariectomized osteoporotic rats. METHODS: Female Wistar rats were ovariectomized and administered different dosage of Icariin and 17beta-estradiol for eight weeks. Bone mineral density (BMD), indexes of biomechanics and bone metabolism-associated biochemical markers were measured. RESULTS: Icariin increased the BMD, maximum load and flexural rigidity in the osteoporotic rats. The activities of serum tartrate-resistant acid phosphatase (TRACP) and bone alkaline phosphatase (BALP) were decreased in the Icraiin-fed ovariectomized rats. CONCLUSION: Icariin 225mg/kg per day could increase the BMD and improve indexes of bone biomechanics in ovariectomized osteoporotic rats. It was effective in preventing bone loss induced by ovariectomy.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Flavonoides/farmacología , Osteoporosis/tratamiento farmacológico , Fosfatasa Ácida/sangre , Fosfatasa Alcalina/sangre , Animales , Fenómenos Biomecánicos , Relación Dosis-Respuesta a Droga , Femenino , Isoenzimas/sangre , Osteoporosis/fisiopatología , Ovariectomía , Ratas , Ratas Wistar , Fosfatasa Ácida Tartratorresistente
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