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1.
Ophthalmic Physiol Opt ; 44(1): 219-228, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37811684

RESUMO

PURPOSE: This study used three-dimensional (3D) modelling to investigate scleral profiles in myopic eyes and compare them with emmetropic eyes. METHODS: In this prospective observational study, the eyes of 151 participants were analysed using the corneoscleral profile module (CSP) of the Pentacam HR. Non-rotationally symmetrical ellipsoids were fitted to the anterior scleral sagittal height. Three radii were analysed, namely the nasal-temporal (Rx), superior-inferior (Ry) and anterior-posterior (Rz) orientations. Additionally, the area index (AI) and aspherical parameters (Qxy, Qxz and Qyz) of the anterior sclera-fitted ellipsoid (ASFE) were quantified. RESULTS: The findings showed an increase in Rx (-0.349 mm/D), Ry (-0.373 mm/D), Rz (-1.232 mm/D) and AI (-36.165 mm2 /D) with increasing myopia. From emmetropia to high myopia, the vertical and horizontal planes of the anterior sclera became increasingly prolate (emmetropia, Qxz: 0.02, Qyz: 0.01; low myopia, Qxz: -0.28, Qyz: -0.28; high myopia, Qxz: -0.41, Qyz: -0.43). There were no significant differences in the coronal plane across the three groups (H = 2.65, p = 0.27). The anterior scleral shape of high myopes in the horizontal and vertical planes was more prolate than that of emmetropes and low myopes (Qxz, high myopes vs. low myopes: p = 0.03, high myopes vs. emmetropes: p < 0.001; Qyz, high myopes vs. low myopes: p = 0.04, high myopes vs. emmetropes: p < 0.001). CONCLUSIONS: As the degree of myopia increased, non-uniform anterior scleral enlargement was observed. These findings provide a better understanding of the anterior segment with varying degrees of myopia.


Assuntos
Miopia , Fosmet , Humanos , Esclera , Miopia/diagnóstico , Emetropia , Estudos Prospectivos
2.
Ophthalmology ; 130(3): 286-296, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36240954

RESUMO

PURPOSE: To evaluate longitudinal changes in macular choroidal thickness (mCT) in myopic children treated for 1 year with repeated low-level red-light (RLRL) therapy and their predictive value for treatment efficacy on myopia control. DESIGN: A secondary analysis of data from a multicenter, randomized controlled trial (RCT; NCT04073238). PARTICIPANTS: Myopic children aged 8-13 years who participated in the RCT at 2 of 5 sites where mCT measurements were available. METHODS: Repeated low-level red-light therapy was delivered using a home-use desktop light device that emitted red-light at 650 nm. Choroidal thickness was measured by SS-OCT at baseline and 1-, 3-, 6-, and 12-month follow-ups. Visual acuity, axial length (AL), cycloplegic spherical equivalent refraction (SER), and treatment compliance were measured. MAIN OUTCOME MEASURES: Changes in mCT at 1, 3, 6, and 12 months relative to baseline, and their associations with myopia control. RESULTS: A total of 120 children were included in the analysis (RLRL group: n = 60; single-vision spectacle [SVS] group: n = 60). Baseline characteristics were well balanced between the 2 groups. In the RLRL group, changes in mCT from baseline remained positive over 1 year, with a maximal increase of 14.755 µm at 1 month and gradually decreasing from 5.286 µm at 3 months to 1.543 µm at 6 months, finally reaching 9.089 µm at 12 months. In the SVS group, mCT thinning was observed, with changes from baseline of -1.111, -8.212, -10.190, and -10.407 µm at 1, 3, 6, and 12 months, respectively. Satisfactory myopia control was defined as annual progression rates of less than 0, 0.05, or 0.10 mm for AL and less than 0, 0.25, or 0.50 diopters for SER. Models that included mCT changes at 3 months alone had acceptable predictive discrimination of satisfactory myopia control over 12 months, with areas under the curve of 0.710-0.786. The predictive performance of the models did not significantly improve after adding age, gender, and baseline AL or SER. CONCLUSIONS: This analysis from a multicenter RCT found RLRL induced sustained choroidal thickening over the full course of treatment. Macular choroidal thickness changes at 3 months alone can predict 12-month myopia control efficacy with reasonable accuracy. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Assuntos
Miopia , Tomografia de Coerência Óptica , Criança , Humanos , Miopia/complicações , Refração Ocular , Acuidade Visual , Corioide , Fototerapia , Comprimento Axial do Olho
3.
Optom Vis Sci ; 100(1): 111-116, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36705721

RESUMO

SIGNIFICANCE: These data demonstrate that defocus incorporated multiple segment (DIMS) lens reduces myopia progression in children during the first year of use. PURPOSE: This study aimed to investigate the efficacy of DIMS myopia control spectacle lens in Chinese myopic children aged 6 to 15 years. METHODS: This is a retrospective study of 1-year longitudinal data. A total of 180 Chinese myopic children were selected from patients at Zhongshan Ophthalmic Center, Sun Yat-sen University, from February 2018 to January 2021. One group consisted of 90 children aged 6 to 15 years, with spherical equivalent refraction -0.50 to -7.75 D (-3.82 ± 1.57 D) and fitted with the DIMS lens. The other group consisted of 90 children fitted with single-vision spectacle lenses and matched with the DIMS group for age, sex, refraction, and progression of myopia in the previous year. One-year myopia progression was measured retrospectively in two groups. Unpaired t test was used to compare the myopia progression between the DIMS group and the control group. Pearson correlation was used to explore the relationship between myopia progression, age, and baseline refraction. RESULTS: After 1 year of DIMS lens wear, myopia progression was significantly lower in the DIMS group (-0.51 ± 0.50 vs. -0.85 ± 0.51 D, P < .001). Myopia progression was positively correlated with age in both groups. The difference between the DIMS and control groups was more pronounced for children aged 10 to 15 years than for children aged 6 to 9 years. CONCLUSIONS: This study confirms that the DIMS lens reduces myopia progression during the first year of use. Efficacy seems to increase with age.


Assuntos
População do Leste Asiático , Miopia , Humanos , Criança , Estudos Retrospectivos , Miopia/diagnóstico , Miopia/terapia , Olho , Refração Ocular , Progressão da Doença
4.
Ophthalmic Physiol Opt ; 43(6): 1427-1437, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37431143

RESUMO

OBJECTIVE: To investigate the effect of repeated low-level red-light therapy (RLRLT) on retinal and choroidal blood perfusion in myopic children. METHODS: Forty-seven myopic children (mean spherical equivalent refractive error [SE]: -2.31 ± 1.26 D; age range: 8.0-11.0 years) were enrolled and received RLRLT (power 2 mW, wavelength 650 nm) for 3 min twice a day, while 20 myopic children (SE: -2.75 ± 0.84 D; age range: 7.0-10.0 years) were included as a control group. All participants wore single-vision distance glasses. Refractive error, axial length (AL) and other biometric parameters were measured at baseline and during follow-up visits in the first, second and fourth weeks after initiation of treatment. Retinal thickness, subfoveal choroidal thickness (SFCT), total choroidal area (TCA), luminal area (LA), stromal area (SA) and choroidal vascularity index (CVI) were obtained using optical coherence tomography (OCT). The percentage retinal vascular density (VD%) and choriocapillaris flow voids (FV%) were measured using en-face OCT angiography. RESULTS: After 4 weeks of treatment, a significant increase in SFCT was observed in the RLRLT group, with an average increase of 14.5 µm (95% confidence interval [CI]: 9.6-19.5 µm), compared with a decrease of -1.7 µm (95% CI: -9.1 to 5.7 µm) in the control group (p < 0.0001). However, no significant changes in retinal thickness or VD% were observed in either group (all p > 0.05). In the OCT images from the RLRLT group, no abnormal retinal morphology related to photodamage was observed. The horizontal scans revealed an increase in TCA, LA and CVI over time (all p < 0.05), while SA and FV% remained unchanged (both p > 0.05). CONCLUSIONS: These findings indicate that RLRLT can enhance choroidal blood perfusion in myopic children, demonstrating a cumulative effect over time.

5.
Eye Contact Lens ; 49(6): 234-240, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36989487

RESUMO

OBJECTIVES: To determine and compare the repeatability and reproducibility of anterior scleral parameters measured by the corneoscleral profile (CSP) module of Pentacam in keratoconus (KC) and control eyes. METHODS: This is a prospective observational study. Thirty KC participants (30 eyes) and 24 control participants (24 eyes) were examined three times using the CSP. Sagittal height mean (SHM), sagittal height astigmatism (SHA), and mean bulbar slope (BSM) were measured in 12 mm and 16 mm chord lengths. The repeatability and reproducibility of these measurements were also assessed. Coefficients of variation (CoV), intraclass correlation coefficient (ICC), coefficient of repeatability (CoR1), and coefficient of reproducibility (CoR2) were adopted to assess the reliability. RESULTS: In the KC and control groups, SHM showed high repeatability and reproducibility (coefficients of variation [CoVs]≤0.96%, intraclass correlation coefficient [ICCs]≥0.97), and SHM of control eyes showed higher repeatability and reproducibility than that of KC eyes at 12 mm chord length (KC group, CoRs ranged from 35.56 µm to 43.52 µm, control group, ranged from 23.50 µm to 30.31 µm) and 16 mm chord length (KC group, CoRs ranged from 79.54 µm to 81.58 µm, control group, ranged from 48.25 µm to 66.10 µm). Mean bulbar slope also showed high repeatability and reproducibility (CoVs≤3.65%, CoRs≤2.64). Furthermore, the SHA of control eyes showed higher repeatability and reproducibility when compared with KC eyes (control group: CoVs≤29.95%, KC group: CoVs≥32.67%). CONCLUSIONS: Keratoconus and control eyes demonstrated high repeatability and reproducibility when using CSP measurements, which may prove helpful in fitting contact lenses.


Assuntos
Astigmatismo , Ceratocone , Humanos , Ceratocone/diagnóstico , Reprodutibilidade dos Testes , Topografia da Córnea/métodos , Córnea
6.
Ophthalmology ; 129(5): 509-519, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34863776

RESUMO

PURPOSE: To assess the efficacy and safety of repeated low-level red-light (RLRL) therapy in myopia control in children. DESIGN: Multicenter, randomized, parallel-group, single-blind clinical trial. PARTICIPANTS: Two hundred sixty-four eligible children 8 to 13 years of age with myopia of cycloplegic spherical equivalent refraction (SER) of -1.00 to -5.00 diopters (D), astigmatism of 2.50 D or less, anisometropia of 1.50 D or less, and best-corrected visual acuity (BCVA) of 0.0 logarithm of the minimum angle of resolution or more were enrolled in July and August 2019. Follow-up was completed in September 2020. METHODS: Children were assigned randomly to the intervention group (RLRL treatment plus single-vision spectacle [SVS]) and the control group (SVS). The RLRL treatment was provided by a desktop light therapy device that emits red light of 650-nm wavelength at an illuminance level of approximately 1600 lux and a power of 0.29 mW for a 4-mm pupil (class I classification) and was administered at home under supervision of parents for 3 minutes per session, twice daily with a minimum interval of 4 hours, 5 days per week. MAIN OUTCOME MEASURES: The primary outcome and a key secondary outcome were changes in axial length and SER measured at baseline and the 1-, 3-, 6-, and 12-month follow-up visits. Participants who had at least 1 postrandomization follow-up visit were analyzed for treatment efficacy based on a longitudinal mixed model. RESULTS: Among 264 randomized participants, 246 children (93.2%) were included in the analysis (117 in the RLRL group and 129 in the SVS group). Adjusted 12-month axial elongation and SER progression were 0.13 mm (95% confidence interval [CI], 0.09-0.17mm) and -0.20 D (95% CI, -0.29 to -0.11D) for RLRL treatment and 0.38 mm (95% CI, 0.34-0.42 mm) and -0.79 D (95% CI, -0.88 to -0.69 D) for SVS treatment. The differences in axial elongation and SER progression were 0.26 mm (95% CI, 0.20-0.31 mm) and -0.59D (95% CI, -0.72 to -0.46 D) between the RLRL and SVS groups. No severe adverse events (sudden vision loss ≥2 lines or scotoma), functional visual loss indicated by BCVA, or structural damage seen on OCT scans were observed. CONCLUSIONS: Repeated low-level red-light therapy is a promising alternative treatment for myopia control in children with good user acceptability and no documented functional or structural damage.


Assuntos
Miopia , Criança , Progressão da Doença , Óculos , Humanos , Fototerapia , Refração Ocular , Método Simples-Cego
7.
Clin Exp Ophthalmol ; 50(9): 1013-1024, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36054314

RESUMO

BACKGROUND: To evaluate the long-term efficacy and safety of continued repeated low-level red-light (RLRL) therapy on myopia control over 2 years, and the potential rebound effect after treatment cessation. METHODS: The Chinese myopic children who originally completed the one-year randomised controlled trial were enrolled. Children continued RLRL-therapy were defined as RLRL-RLRL group, while those who stopped and switched to single-vision spectacle (SVS) in the second year were RLRL-SVS group. Likewise, those who continued to merely wear SVS or received additional RLRL-therapy were SVS-SVS and SVS-RLRL groups, respectively. RLRL-therapy was provided by an at-home desktop light device emitting red-light of 650 nm and was administered for 3 min at a time, twice a day and 5 days per week. Changes in axial length (AL) and cycloplegic spherical equivalence refraction (SER) were measured. RESULTS: Among the 199 children who were eligible, 138 (69.3%) children attended the examination and 114 (57.3%) were analysed (SVS-SVS: n = 41; SVS-RLRL: n = 10; RLRL-SVS: n = 52; RLRL-RLRL: n = 11). The baseline characteristics were balanced among four groups. In the second year, the mean changes in AL were 0.28 ± 0.14 mm, 0.05 ± 0.24 mm, 0.42 ± 0.20 mm and 0.12 ± 0.16 mm in SVS-SVS, SVS-RLRL, RLRL-SVS and RLRL-RLRL group, respectively (p < 0.001). The respective mean SER changes were -0.54 ± 0.39D, -0.09 ± 0.55D, -0.91 ± 0.48D, and -0.20 ± 0.56D (p < 0.001). Over the 2-year period, axial elongation and SER progression were smallest in RLRL-RLRL group (AL: 0.16 ± 0.37 mm; SER: -0.31 ± 0.79D), followed by SVS-RLRL (AL: 0.44 ± 0.37 mm; SER: -0.96 ± 0.70D), RLRL-SVS (AL: 0.50 ± 0.28 mm; SER: -1.07 ± 0.69D) and SVS-SVS group (AL: 0.64 ± 0.29 mm; SER: -1.24 ± 0.63D). No self-reported adverse events, functional or structural damages were noted. CONCLUSIONS: Continued RLRL therapy sustained promising efficacy and safety in slowing myopia progression over 2 years. A modest rebound effect was noted after treatment cessation.


Assuntos
Miopia , Criança , Humanos , Comprimento Axial do Olho , Progressão da Doença , Óculos , Seguimentos , Fototerapia , Refração Ocular
8.
Ophthalmic Physiol Opt ; 40(5): 567-576, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32839973

RESUMO

PURPOSE: To investigate the inhibitory effect of bendazol on form-deprivation myopia (FDM) in rabbits as well as the underlying biochemical processes. METHODS: Forty-eight 3-week-old New Zealand white rabbits were randomly assigned to three groups: a control group, a form-deprivation (FD) group and an FD + bendazol group (treated with 1% bendazol in the FD eyes). Refraction, corneal curvature, vitreous chamber depth (VCD) and axial length (AL) were assessed using streak retinoscopy, keratometry, and A-scan ultrasonography, respectively. Eyeballs were enucleated for histological analysis, and ocular tissues were homogenized to determine the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and muscarinic acetylcholine receptors (mAChRs). RESULTS: Bendazol inhibited the progression of FDM and suppressed the upregulation of HIF-1α. At week 6, in the control, FD and FD + bendazol groups, the refraction values were 1.38 ± 0.43, 0.03 ± 0.47 and 1.25 ± 0.35 D, respectively (p < 0.001); the ALs were 13.91 ± 0.11, 14.15 ± 0.06 and 13.97 ± 0.10 mm, respectively (p < 0.001) and the VCDs were 6.56 ± 0.06, 6.69 ± 0.07 and 6.61 ± 0.06 mm, respectively (p < 0.001). HIF-1α was upregulated in FD eyes but downregulated in FD + bendazol eyes, while the mAChRs were the opposite. CONCLUSIONS: In the FD rabbit model, bendazol significantly inhibits the development of myopia and downregulates HIF-1α expression, which may provide a novel therapeutic approach for myopia control.


Assuntos
Segmento Anterior do Olho , Benzimidazóis , Subunidade alfa do Fator 1 Induzível por Hipóxia , Miopia Degenerativa , Animais , Coelhos , Segmento Anterior do Olho/metabolismo , Anti-Hipertensivos/administração & dosagem , Benzimidazóis/administração & dosagem , Biomarcadores/metabolismo , Córnea/metabolismo , Córnea/patologia , Modelos Animais de Doenças , Progressão da Doença , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Miopia Degenerativa/diagnóstico , Miopia Degenerativa/tratamento farmacológico , Miopia Degenerativa/metabolismo , Soluções Oftálmicas
9.
Eye Contact Lens ; 46(6): 381-384, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31517738

RESUMO

PURPOSE: To provide fitting guidelines with suggested powers and base curves (BCs) and diameters for initial rigid gas-permeable (RGP) contact lenses (CLs) selection for unilateral aphakic infants based on age. METHODS: Records of 52 children (52 eyes) with RGP CLs to unilateral aphakia between 2014 and 2019 were evaluated. Refractive status was assessed by standard retinoscopy. The original BC and diameter were determined by keratometric readings and fluorescein pattern under sedation. Correlation analysis was performed between age and CLs parameters. Linear regression analysis was used to develop a model for estimating power with the help of infant's age. Subgroup analysis was performed by grouping the eyes into four groups according to age. Lens adjustments and adverse events were also evaluated. RESULTS: The median age was 9.0 months (interquartile range [IQR], 5.25-13.0 months). The mean power and BC and diameter of the initial RGP CLs were 25.46±4.83 diopters, 7.57±0.40 mm, and 9.48±0.23 mm, respectively. All these parameters showed correlations with infant's age (Pearson r=-0.676, 0.367, and 0.497, respectively; P=0.000, 0.008, and 0.000, respectively). Regression analysis revealed that CL power =31.66 to 0.62×age (P<0.001). The median follow-up was 7.50 months (IQR, 3.0-11.0 months). Lens adjustments took about every 3 months before 1 year of age and every 5 months afterward (F=3.442; P=0.024). The RGP CLs provided ideal fit characteristics, and no severe lens-related adverse event occurred except only one patient had mild conjunctivitis. CONCLUSIONS: Our empirical RGP CLs fitting philosophy presented that aphakic infant's age can be used to determine the initial lens if accurate biometry cannot be obtained initially.


Assuntos
Afacia , Lentes de Contato , Criança , Córnea , Humanos , Lactente , Filosofia , Ajuste de Prótese
10.
Exp Eye Res ; 187: 107780, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31469983

RESUMO

Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults, which has a high rate of metastases and can induce vision loss and even death to the patients. To identify suitable prognostic markers of UM for the early detection or prognosis prediction would be an essential step toward successful management of the disease. Herein, we extracted the mRNA expression data along with the clinical information from The Cancer Genome Atlas (TCGA) database. A total of eight co-expression modules were constructed by 5,000 genes based on the weighted gene co-expression network analysis (WGCNA). We found the blue and yellow modules were significantly associated with clinical stage. The Cox regression analyses found the blue, yellow, green and brown modules were significantly associated with overall survival (OS), while the blue, yellow, brown, green and pink modules were significantly associated with recurrence-free survival (RFS). Furthermore, the hallmark pathway enrichment analyses found the genes encompassed in the blue, yellow, and brown modules were significantly enriched in critical pathways involved in tumorigenesis and progression process, such as EMT and KRAS pathways. The hub-genes in these three modules were visualized by Cytoscape software and further validated by an external Gene Expression Omnibus (GEO) dataset. Besides, the OS and RFS predicting signatures were constructed based on the validated hub-genes according to the LASSO Cox regression model. The UM patients were assigned to low-/high-risk population. The survival analyses indicated high-risk patients mostly had bad OS/RFS rate compared with the low-risk population. The receiver operating characteristic (ROC) curve proved the stability and superiority of the two signatures. To sum up, our findings provide a framework of co-expression network of UM and identify a series of biomarkers, which will benefit from improving the prognosis prediction of UM patients.


Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Melanoma/genética , Proteínas de Neoplasias/genética , Neoplasias Uveais/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , RNA Mensageiro/genética , Curva ROC , Transcriptoma , Células Tumorais Cultivadas
11.
Nano Lett ; 18(12): 7962-7968, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30403355

RESUMO

Due to the nontrivial topological band structure in type II Weyl semi-metal tungsten ditelluride (WTe2), unconventional properties may emerge in its superconducting phase. While realizing intrinsic superconductivity has been challenging in the type II Weyl semi-metal WTe2, the proximity effect may open an avenue for the realization of superconductivity. Here, we report the observation of proximity-induced superconductivity with a long coherence length along the c axis in WTe2 thin flakes based on a WTe2/NbSe2 van der Waals heterostructure. Interestingly, we also observe anomalous oscillations of the differential resistance during the transition from the superconducting to the normal state. Theoretical calculations show excellent agreement with experimental results, revealing that such a subgap anomaly is the intrinsic property of WTe2 in superconducting state induced by the proximity effect. Our findings enrich the understanding of the superconducting phase of type II Weyl semi-metals and pave the way for their future applications in topological quantum computing.

12.
Nano Lett ; 18(12): 7538-7545, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30480455

RESUMO

Nanostructuring is an extremely promising path to high-performance thermoelectrics. Favorable improvements in thermal conductivity are attainable in many material systems, and theoretical work points to large improvements in electronic properties. However, realization of the electronic benefits in practical materials has been elusive experimentally. A key challenge is that experimental identification of the quantum confinement length, below which the thermoelectric power factor is significantly enhanced, remains elusive due to lack of simultaneous control of size and carrier density. Here we investigate gate-tunable and temperature-dependent thermoelectric transport in γ-phase indium selenide (γ-InSe, n-type semiconductor) samples with thickness varying from 7 to 29 nm. This allows us to properly map out dimension and doping space. Combining theoretical and experimental studies, we reveal that the sharper pre-edge of the conduction-band density of states arising from quantum confinement gives rise to an enhancement of the Seebeck coefficient and the power factor in the thinner InSe samples. Most importantly, we experimentally identify the role of the competition between quantum confinement length and thermal de Broglie wavelength in the enhancement of power factor. Our results provide an important and general experimental guideline for optimizing the power factor and improving the thermoelectric performance of two-dimensional layered semiconductors.

13.
Nano Lett ; 18(2): 1410-1415, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29385803

RESUMO

Layered metal chalcogenide materials provide a versatile platform to investigate emergent phenomena and two-dimensional (2D) superconductivity at/near the atomically thin limit. In particular, gate-induced interfacial superconductivity realized by the use of an electric-double-layer transistor (EDLT) has greatly extended the capability to electrically induce superconductivity in oxides, nitrides, and transition metal chalcogenides and enable one to explore new physics, such as the Ising pairing mechanism. Exploiting gate-induced superconductivity in various materials can provide us with additional platforms to understand emergent interfacial superconductivity. Here, we report the discovery of gate-induced 2D superconductivity in layered 1T-SnSe2, a typical member of the main-group metal dichalcogenide (MDC) family, using an EDLT gating geometry. A superconducting transition temperature Tc ≈ 3.9 K was demonstrated at the EDL interface. The 2D nature of the superconductivity therein was further confirmed based on (1) a 2D Tinkham description of the angle-dependent upper critical field Bc2, (2) the existence of a quantum creep state as well as a large ratio of the coherence length to the thickness of superconductivity. Interestingly, the in-plane Bc2 approaching zero temperature was found to be 2-3 times higher than the Pauli limit, which might be related to an electric field-modulated spin-orbit interaction. Such results provide a new perspective to expand the material matrix available for gate-induced 2D superconductivity and the fundamental understanding of interfacial superconductivity.

14.
Mol Vis ; 23: 1006-1014, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29386874

RESUMO

Purpose: To evaluate the effects of 7-methylxanthine (7-MX) on the growth of human retinal pigment epithelium (RPE) cells and to observe the changes in the expression of adenosine receptors (ADORs) in RPE cells upon 7-MX treatment. Methods: Human RPE cells (monolayer at about 80% confluence) were cultured in vitro in the presence or absence of 7-MX. Cell proliferation was evaluated with 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The cell cycle distribution and apoptosis level were analyzed with flow cytometry. Quantitative PCR and immunofluorescence assay were used to examine the mRNA and protein expression of ADORs. Results: 7-MX at low concentrations had no effect on the proliferation of RPE cells, whereas 100 µmol/l 7-MX slightly decreased cell proliferation at 48 h but without a statistically significant difference. The 7-MX treatment was performed at the low concentration of 10 µmol/l in the following experiments. The proportion of RPE cells in the G1 stage was slightly increased at 24 h (p=0.035) but decreased at 48 h (p=0.0045) upon 7-MX treatment; and the proportion was restored to normal at 72 h. No statistically significant change in apoptosis levels was found in RPE cells cultured with 7-MX. The expression of ADORA1, ADORA2A, and ADORA2B in RPE cells was inhibited by 7-MX treatment at 48 h, while the expression levels appeared to rebound at 72 h. Conclusions: 7-MX has little effect on the proliferation or apoptosis level of human RPE cells; however, in short-term treatment, 7-MX disturbs the proportion of cells in the G1 stage and inhibits the expression of ADORA1, ADORA2A, and ADORA2B.


Assuntos
Epitélio Pigmentado da Retina/efeitos dos fármacos , Xantinas/farmacologia , Adulto , Apoptose/efeitos dos fármacos , Ciclo Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Humanos , Masculino , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Purinérgicos P1/metabolismo , Epitélio Pigmentado da Retina/metabolismo
15.
Nano Lett ; 16(4): 2254-9, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-26886761

RESUMO

van der Waals junctions of two-dimensional materials with an atomically sharp interface open up unprecedented opportunities to design and study functional heterostructures. Semiconducting transition metal dichalcogenides have shown tremendous potential for future applications due to their unique electronic properties and strong light-matter interaction. However, many important optoelectronic applications, such as broadband photodetection, are severely hindered by their limited spectral range and reduced light absorption. Here, we present a p-g-n heterostructure formed by sandwiching graphene with a gapless band structure and wide absorption spectrum in an atomically thin p-n junction to overcome these major limitations. We have successfully demonstrated a MoS2-graphene-WSe2 heterostructure for broadband photodetection in the visible to short-wavelength infrared range at room temperature that exhibits competitive device performance, including a specific detectivity of up to 10(11) Jones in the near-infrared region. Our results pave the way toward the implementation of atomically thin heterostructures for broadband and sensitive optoelectronic applications.

16.
Br J Ophthalmol ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38527770

RESUMO

AIMS: To examine differences between the eyes in choriocapillaris perfusion and choroidal thickness in children with myopic anisometropia. METHODS: In this observational and prospective study, 46 children with myopic anisometropia were enrolled. Choriocapillaris perfusion parameters, including the percentage of flow voids, the total number of flow voids and the average flow void area were obtained by optical coherence tomography angiography (OCTA). The OCTA image was divided into a 1 mm-diameter central circle (C1) and a 2.5 mm-diameter annulus (without the inner central 1 mm circle, C1-2.5). Both C1 and C1-2.5 are centred on the foveola. The C1-2.5 was divided into nasal (N1-2.5), temporal (T1-2.5), inferior (I1-2.5) and superior (S1-2.5) areas. Differences in these parameters in different regions between eyes were analysed. RESULTS: There were no significant differences in the percentage of flow voids and the average flow void area between the fellow eyes. The total number of signal voids was significantly higher in the less myopic eyes in C1-2.5 (p=0.032), S1-2.5 (p=0.008) and N1-2.5 (p=0.019). Changes in spherical equivalent refraction and axial length were both correlated with the changes in the total number of flow voids in N1-2.5 (R=-0.431, p=0.03; R=-0.297, p=0.047). CONCLUSIONS: The choroid in the macular region becomes thinner and the total number of flow voids in the nasal macular region decreased with the amplitude of myopia. This suggests that a decrease in total number of flow voids may indicate an early change in myopia.

17.
Mol Vis ; 19: 1795-803, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23946634

RESUMO

PURPOSE: All-trans retinoic acid (ATRA) is known to inhibit the proliferation of human scleral fibroblasts (HSFs) and to modulate the scleral intercellular matrix composition, and may therefore serve as a mediator for controlling eye growth. Cell proliferation is regulated by the mitogen-activated protein kinase (MAPK) pathway. The aim of the current study was to investigate whether changed activation of the MAPK pathway could be involved in the response of HSFs exposed to ATRA. METHODS: HSFs were cultured in Dulbecco Modified Eagle's Medium/F12 (DMEM/F12) and exposed to 1 µmol/l ATRA for 10 min, 30 min, 1 h, 8 h, or 24 h. The activation of extracellular signal-regulated kinase (ERK 1/2), p38, and c-Jun N-terminal kinase (JNK) in HSFs was assessed with western blot analysis and immunocytofluorescence. RESULTS: After exposure to ATRA for 24 h, the HSFs appeared shrunken and thinner than the control cells. The intercellular spaces were wider, and the HSFs appeared less numerous than in the control culture. Western blot showed decreased activation of ERK 1/2 in the HSFs from 30 min (p=0.01) to 24 h (p<0.01) after the start of exposure to ATRA, and increased activation of the JNK protein from 10 to 30 min (p<0.01) after the start of exposure to ATRA. Indirect immunofluorescence confirmed changes in activation of ERK 1/2 and JNK in HSFs exposed to ATRA. No change in activation of p38 in HSFs was observed after exposure to ATRA. Pretreatment of the HSFs with LE135, an antagonist of retinoic acid receptor beta (RARß), abolished the ATRA-induced changes inactivation of ERK 1/2 and JNK. CONCLUSIONS: ATRA inhibits HSF proliferation by a mechanism associated with modulation of ERK 1/2 and JNK activation and depends on stimulation of retinoic acid receptor beta.


Assuntos
Fibroblastos/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores do Ácido Retinoico/metabolismo , Esclera/citologia , Tretinoína/farmacologia , Forma Celular/efeitos dos fármacos , Células Cultivadas , Dibenzazepinas/farmacologia , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Eye (Lond) ; 37(6): 1264-1270, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35610360

RESUMO

PURPOSE: Increasing evidence suggests myopia is not a simple refractive error, many other factors might also be involved. Here, we assessed myopic and normal corneas' gene expression profiles to identify possible diagnostic and therapeutic biomarkers for myopia. MATERIALS AND METHODS: We obtained the expression profile of ten patients and seven normal control samples from the GSE112155 and GSE151631 datasets based on the Gene Expression Omnibus (GEO) database. We used the "limma" R package to determine the differentially expressed genes (DEGs) between myopic and normal corneas. Weighted gene co-expression network analysis (WGCNA) was used to identify critical co-expressed modules related to myopia, and enrichment analyses were used to annotate the function of genes encompassed in the compulsory module. We also validated these findings in two external datasets (GSE24641 and GSE136701). RESULTS: We identified that the DEGs were significantly enriched in ultraviolet (UV) response, TNF-α signaling via NFκB, Angiogenesis, Myogenesis pathways, etc. We used 2095 genes to construct the co-expression gene modules and found five interesting modules because the eigengene expression of these modules was significantly differentially expressed between myopic and normal corneas. Notably, the enrichment analysis found that the genes encompassed in lightgreen module were significantly enriched in immune-related pathways. These findings were proved by subsequent analysis based on Xcell software. We found the component of B cells, CD4+ memory T cells, CD8+ central memory T cells, plasmacytoid dendritic cells, T helper 2 (Th2) cells, regulatory T cells (Tregs), etc. were significantly increased in myopic corneas, while CD8+ T cells, CD4+ T central memory cells, natural killer T (NKT) cells, and T helper 1 (Th1) cells were significantly decreased. CONCLUSION: Our findings identified some markers that might detect diagnosis and treatment for myopia from cornea aspect. Future studies are warranted to verify the functional role of immune-related pathways in cornea during the pathogenesis or progression of myopia.


Assuntos
Miopia , Erros de Refração , Humanos , Transcriptoma , Miopia/diagnóstico , Miopia/genética , Perfilação da Expressão Gênica , Biomarcadores
19.
PeerJ ; 11: e16425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025747

RESUMO

Purpose: Bright light conditions are supposed to curb eye growth in animals with experimental myopia. Here we investigated the effects of temporal bright light at very low frequencies exposures on lens-induced myopia (LIM) progression. Methods: Myopia was induced by application of -6.00 D lenses over the right eye of guinea pigs. They were randomly divided into four groups based on exposure to different lighting conditions: constant low illumination (CLI; 300 lux), constant high illumination (CHI; 8,000 lux), very low frequency light (vLFL; 300/8,000 lux, 10 min/c), and low frequency light (LFL; 300/8,000 lux, 20 s/c). Refraction and ocular dimensions were measured per week. Changes in ocular dimensions and refractions were analyzed by paired t-tests, and differences among the groups were analyzed by one-way ANOVA. Results: Significant myopic shifts in refractive error were induced in lens-treated eyes compared with contralateral eyes in all groups after 3 weeks (all P < 0.05). Both CHI and LFL conditions exhibited a significantly less refractive shift of LIM eyes than CLI and vLFL conditions (P < 0.05). However, only LFL conditions showed significantly less overall myopic shift and axial elongation than CLI and vLFL conditions (both P < 0.05). The decrease in refractive error of both eyes correlated significantly with axial elongation in all groups (P < 0.001), except contralateral eyes in the CHI group (P = 0.231). LFL condition significantly slacked lens thickening in the contralateral eyes. Conclusions: Temporal bright light at low temporal frequency (0.05 Hz) appears to effectively inhibit LIM progression. Further research is needed to determine the safety and the potential mechanism of temporal bright light in myopic progression.


Assuntos
Iluminação , Miopia , Animais , Cobaias , Olho , Miopia/prevenção & controle , Refração Ocular , Erros de Refração
20.
Asia Pac J Ophthalmol (Phila) ; 12(4): 377-383, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37523429

RESUMO

PURPOSE: Repeated low-level red-light (RLRL) therapy has been confirmed as a novel intervention for myopia control in children. This study aims to investigate longitudinal changes in choroidal structure in myopic children following 12-month RLRL treatment. MATERIALS AND METHODS: The current study is a secondary analysis from a multicenter, randomized controlled trial (NCT04073238). Choroidal parameters were derived from baseline and follow-up swept-source optical coherence tomography scans taken at 1, 3, 6, and 12 months. These parameters included the luminal area (LA), stromal area (SA), total choroidal area (TCA; a combination of LA and SA), and choroidal vascularity index (CVI; ratio of LA to TCA), which were automatically measured by a validated custom choroidal structure assessment tool. RESULTS: A total of 143 children (88.3% of all participants) with sufficient image quality were included in the analysis (n=67 in the RLRL and n=76 in the control groups). At the 12-month visit, all choroidal parameters increased in the RLRL group, with changes from baseline of 11.70×10 3  µm 2 (95% CI: 4.14-19.26×10 3  µm 2 ), 3.92×10 3  µm 2 (95% CI: 0.56-7.27×10 3  µm 2 ), 15.61×10 3  µm 2 (95% CI: 5.02-26.20×10 3  µm 2 ), and 0.21% (95% CI: -0.09% to 0.51%) for LA, SA, TCA, and CVI, respectively, whereas these parameters reduced in the control group. CONCLUSIONS: Following RLRL therapy, the choroidal thickening was found to be accompanied by increases in both the vessel LA and SA, with the increase in LA being greater than that of SA. In the control group, with myopia progression, both the LA and SA decreased over time.


Assuntos
Corioide , Miopia , Criança , Humanos , Luz , Miopia/terapia , Tomografia de Coerência Óptica , Fototerapia
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