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1.
ACS Appl Mater Interfaces ; 16(8): 10417-10426, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38375798

RESUMO

Organic semiconducting materials are promising for the fabrication of flexible ionizing radiation detectors for imaging because of their tissue equivalence, simple large-scale processing, and mass production. However, it is challenging to achieve high-sensitivity detection for organic direct detectors prepared by low-cost solution processing because of the compromise between thickness and carrier transport. In this study, high-performance organic direct X-ray detectors were fabricated by building a micrometer-thick bulk heterojunction (BHJ) using poly(3-hexylthiophene-2,5-diyl) (P3HT):(6,6)-phenyl c71 butyric acid methyl ester. A 5 µm BHJ film was fabricated by drop-casting and enhanced crystallization of P3HT using binary solvents and high-boiling-point additives to improve the charge carrier mobility. Furthermore, this organic direct X-ray detector has a sensitivity of >654.26 µC Gyair s-1 and a self-powered response. Because of the architecture of the thick active layer and the energy cascade in this diode detector, it has a very low dark current of 46.26 pA at -2 V. A fast and efficient approach was developed for fabricating thick, highly mobile organic BHJ films for high-performance direct X-ray detectors. It has great potential for application in a new generation of flexible and portable large-area flat-panel detectors.

2.
Curr Eye Res ; 48(11): 1068-1077, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37555317

RESUMO

PURPOSE: This study aimed to automatically and quantitatively analyse the characteristics of the optic disc by applying artificial intelligence (AI) to fundus images. METHODS: A total of 1084 undergraduates were recruited in this cross-sectional study. The optic disc area, cup-to-disc ratio (C/D), optic disc tilt, and the area, width, and height of peripapillary atrophy (PPA) were automatically and quantitatively detected using AI. Based on axial length (AL), participants were divided into five groups: Group 1 (AL ≤ 23 mm); Group 2 (23 mm < AL≤ 24 mm); Group 3 (24 mm < AL≤ 25 mm); Group 4 (25 mm < AL< 26 mm) and Group 5 (AL ≥ 26 mm). Relationships between ocular parameters and optic disc characteristics were analysed. RESULT: A total of 999 undergraduates were included in the analysis. The prevalence of optic disc tilting and PPA were 47.1% and 92.5%, respectively, and increased with the severity of myopia. The mean optic disc area, PPA area, C/D, and optic disc tilt ratio were 1.97 ± 0.46 mm2, 0.84 ± 0.59 mm2, 0.18 ± 0.07, and 0.81 ± 0.08, respectively. In Group 5, the average optic disc area (1.84 ± 0.41 mm2) and optic disc tilt ratio (0.79 ± 0.08) were significantly smaller and the PPA area (1.12 ± 0.61 mm2) was significantly larger than those in the other groups. AL was negatively correlated with optic disc area and optic disc tilt ratio (r=-0.271, -0.219; both p < 0.001) and positively correlated with PPA area, width, and height (r = 0.421, 0.426, 0.345; all p < 0.01). A greater AL (ß = 0.284, p < 0.01) and a smaller optic disc tilt ratio (ß=-0.516, p < 0.01) were related to a larger PPA area. CONCLUSION: The characteristics of the optic disc can be feasibly and efficiently extracted using AI. The quantization of the optic disc might provide new indicators for clinicians to evaluate the degree of myopia.

3.
Eye Contact Lens ; 49(9): 404-410, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284749

RESUMO

OBJECTIVE: To conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) on the effects of orthokeratology for slowing myopia progression in children. METHODS: We performed a specific search on PubMed, Embase, Cochrane Library, Clinical Trials, CNKI, SinoMed, and Wanfang Data for RCTs conducted up to October 1, 2022. We pooled the weighted mean difference (WMD) between the orthokeratology and control groups for axial length (AL) elongation and the odds ratio (OR) for rates of adverse events and dropout. RESULTS: Seven RCTs involving 655 eyes were included. There were significant differences in the effects of orthokeratology versus control in slowing AL elongation with WMD of -0.11 mm (95% confidence interval (CI), -0.13 to -0.08; P <0.01) at 6 months, -0.16 mm (95% CI, -0.18 to -0.13; P <0.01) at 12 months, -0.23 mm (95% CI, -0.29 to -0.18; P <0.01) at 18 months, and -0.28 mm (95% CI, -0.38 to -0.19; P <0.01) at 24 months, respectively. Myopia control rate declined, with 64%, 53%, 50%, and 47% recorded for 6, 12, 18, and 24 months, respectively. There was no statistical significance for adverse events between orthokeratology and control groups (OR=2.63, 95% CI, 0.72-9.61; P =0.11). CONCLUSION: Orthokeratology can effectively slow myopia progression in children, and the efficacy of myopia control decreases with time.


Assuntos
Miopia , Procedimentos Ortoceratológicos , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Miopia/terapia , Comprimento Axial do Olho , Razão de Chances , Refração Ocular
4.
BMC Oral Health ; 23(1): 333, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37244990

RESUMO

BACKGROUND: Tooth loss may be a surrogate for systemic health and aging. However, no previous studies have systematically assessed multiple outcomes relevant to aging trajectory in this area, and many important confounders were not adjusted in most previous studies. This study aims to prospectively evaluate the associations of complete tooth loss (edentulism) with broad markers of sarcopenia, cognitive impairment and mortality. METHODS: Data were derived from the China Health and Retirement Longitudinal Study, a nationally representative household study of the Chinese population aged 45 years and older. Multivariate Weibull proportional hazards regression was used to assess the association between edentulism with sarcopenia and all-cause mortality. Average changes in cognitive function by edentulism was estimated by mixed-effects linear regression models. RESULTS: During the 5-year follow-up, the prevalence of edentulism among adults aged 45 and over was 15.4%. Participants with edentulism had a greater decline in cognitive function compared to those without (ß=-0.70, 95%CI:-1.09, -0.31, P < 0.001). The association of edentulism and all-cause mortality for 45-64 age group (HR = 7.50, 95%CI: 1.99, 28.23, P = 0.003), but not statistically significant for the ≥ 65 age group (HR = 2.37, 95%CI: 0.97, 5.80, P = 0.057). Effects of edentulism on sarcopenia are statistically significant for all age groups (45-64 age group: HR = 2.15, 95%CI: 1.27, 3.66, P = 0.005; ≥65 age group: HR = 2.15, 95%CI: 1.27, 3.66, P = 0.002). CONCLUSIONS: These findings could have important clinical and public health implications, as tooth loss is a quick and reproducible measurement that could be used in clinical practice for identifying persons at risk of accelerated aging and shortened longevity, and who may benefit most from intervention if causality is established.


Assuntos
Disfunção Cognitiva , Mortalidade , Sarcopenia , Perda de Dente , Idoso , Humanos , Pessoa de Meia-Idade , Disfunção Cognitiva/complicações , Disfunção Cognitiva/epidemiologia , População do Leste Asiático , Estudos Longitudinais , Sarcopenia/complicações , Sarcopenia/epidemiologia , Perda de Dente/complicações , Perda de Dente/epidemiologia
5.
Ophthalmic Res ; 66(1): 706-716, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36854278

RESUMO

INTRODUCTION: The aim of this study was to quantitatively assess fundus tessellated density (FTD) and associated factors by artificial intelligence (AI) in young adults. METHODS: A total of 1,084 undergraduates (age, 17-23 years old) were enrolled in November 2021. The students were divided into three groups according to axial length (AL): group 1 (AL <24.0 mm, n = 155), group 2 (24 mm ≤ AL <26 mm, n = 578), and group 3 (AL ≥26 mm, n = 269). FTD was calculated by extracting the fundus tessellations as the regions of interest (circle 1, diameter of 3.0 mm; circle 2, diameter of 6.0 mm) and then calculating the average exposed choroid area per unit area of fundus. RESULTS: Among 1,084 students, 1,002 (92.5%) students' FTDs were extracted. The mean FTD was 0.06 ± 0.06 (range, 0-0.40). In multivariate analysis, FTD was significantly associated with male sex, longer AL, thinner subfoveal choroid thickness (SFCT), increased choriocapillaris vessel density (VD), and decreased deeper choroidal VD (all p < 0.05). In circle 1 (diameter of 3.0 mm) and circle 2 (diameter of 6.0 mm), analysis of variance showed that the FTD of the nasal region (p < 0.05) was significantly larger than that of the superior, inferior, and temporal regions. CONCLUSION: AI-based imaging processing could improve the accuracy of fundus tessellation diagnosis. FTD was significantly associated with a longer AL, thinner SFCT, increased choriocapillaris VD, and decreased deeper choroidal VD.


Assuntos
Inteligência Artificial , Demência Frontotemporal , Humanos , Masculino , Adulto Jovem , Adolescente , Adulto , Fundo de Olho , Corioide , Tomografia de Coerência Óptica
6.
Invest Ophthalmol Vis Sci ; 62(7): 20, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34137807

RESUMO

Purpose: Synaptosomal actin dynamics are essential for synaptic structural stability. Whether actin dynamics are involved in structural and functional synaptic plasticity within the primary visual cortex (V1) or behavioral visual acuity in rats has still not been thoroughly investigated. Methods: Synaptosome preparation and western blot analysis were used to analyze synaptosomal actin dynamics. Transmission electron microscopy was used to detect synaptic density and mitochondrial area alterations. A visual water maze task was applied to assess behavioral visual acuity. Microinjection of the actin polymerization inhibitor or stabilizer detected the effect of actin dynamics on visual function. Results: Actin dynamics, the mitochondrial area, and synaptic density within the area of V1 are increased during the critical period for the development of binocularity. Microinjection of the actin polymerization inhibitor cytochalasin D into the V1 decreased the mitochondrial area, synaptic density, and behavioral visual acuity. Long-term monocular deprivation reduced actin dynamics, the mitochondrial area, and synaptic density within the V1 contralateral to the deprived eye compared with those ipsilateral to the deprived eye and impaired visual acuity in the amblyopic eye. In addition, the mitochondrial area, synaptic density, and behavioral visual acuity were improved by stabilization of actin polymerization by jasplakinolide microinjection. Conclusions: During the critical period of visual development of binocularity, synaptosomal actin dynamics regulate synaptic structure and function and play roles in behavioral visual acuity in rats.


Assuntos
Actinas , Plasticidade Neuronal/fisiologia , Sinaptossomos/metabolismo , Acuidade Visual/fisiologia , Córtex Visual/fisiologia , Actinas/química , Actinas/metabolismo , Ambliopia/metabolismo , Ambliopia/fisiopatologia , Animais , Antineoplásicos/farmacologia , Comportamento Animal/fisiologia , Depsipeptídeos/farmacologia , Aprendizagem em Labirinto , Polimerização/efeitos dos fármacos , Ratos , Visão Ocular/fisiologia
7.
Cutan Ocul Toxicol ; 40(3): 187-197, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33487044

RESUMO

OBJECTIVE: Oxidative stress has been recognised as an important mediator of apoptosis in lens epithelial cells. It also plays an important role in the pathogenesis of cataracts. It is reported that (-)-Epigallocatechin gallate (EGCG), the most abundant component in green tea, exhibits potent antioxidant activity against oxidative stress. This study aimed to investigate the protective effect of EGCG against Ultraviolet B (UVB) induced apoptotic death and the underlying mechanism in human lens epithelial cells (HLECs). METHODS: HLECs were exposed to various concentrations of EGCG under UVB (30 mJ/cm2), and cell viability was monitored by the MTT assay. Next, mitochondrial membrane potential (Δψm), reactive oxygen species (ROS) and apoptosis were detected by flow cytometry. Meanwhile, the total antioxigenic capacity (T-AOC) was determined by enzyme standard instrument, and the expression of apoptosis inducing factor (AIF) and endonuclease G (Endo G) was measured by quantitative PCR (Q-PCR) and western blotting, respectively. Moreover, the localisation of AIF and Endo G within cells was further detected by confocal optical microscopy. RESULTS: The results indicated that EGCG could enhance the cell viability and protect against cell apoptosis caused by UVB irradiation in HLECs. EGCG could also decrease the UVB-induced generation of ROS and collapse of Δψm, increase the T-AOC level. In addition, EGCG could also inhibit the UVB-stimulated increase of AIF and Endo G expression at mRNA and protein levels and ameliorate the UVB-induced mitochondria-nuclear translocation of AIF and Endo G. CONCLUSIONS: UVB irradiation could damage HLECs viability, while EGCG exhibits antioxidant effect and inhibits UVB-induced apoptosis in HLECs through AIF/Endo G signalling pathways. Our findings reveal the underlying mechanism of EGCG against UVB-induced oxidative stress in HLECs.


Assuntos
Catarata/tratamento farmacológico , Catequina/análogos & derivados , Cristalino/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Fator de Indução de Apoptose/metabolismo , Catarata/etiologia , Catarata/patologia , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Endodesoxirribonucleases/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/efeitos da radiação , Humanos , Cristalino/citologia , Cristalino/patologia , Cristalino/efeitos da radiação , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos
8.
J Neurophysiol ; 120(3): 1307-1317, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29790836

RESUMO

Intracerebral hemorrhage (ICH) is a devastating disease worldwide with increasing mortality. The present study investigated whether minocycline was neuroprotective and induced M2 microglial polarization via upregulation of the TrkB/BDNF pathway after ICH. ICH was induced via injection of autologous blood into 150 Sprague-Dawley rats. A selective TrkB antagonist [N2-2-2-oxoazepan-3-yl amino] carbonyl phenyl benzo (b) thiophene-2-carboxamide (ANA 12)] and agonist [ N-[2-(5-hydroxy-1H-indol-3-yl) ethyl]-2-oxopiperidine-3-carboxamide (HIOC)] were used to investigate the mechanism of minocycline-induced neuroprotection. Minocycline improved ICH-induced neurological deficits and reduced M1 microglia marker protein (CD68, CD16) expression as well as M2 microglial polarization (CD206 and arginase 1 protein). Minocycline administration enhanced microglia-neuron cross talk and promoted the proliferation of neuronal progenitor cells, such as DCX- and Tuj-1-positive cells, 24 h after ICH. Minocycline also increased M2 microglia-derived brain-derived neurotrophic factors (BDNF) and the upstream TrkB pathway. ANA 12 reversed the neuroprotective effects of minocycline. HIOC exhibited the same effects as minocycline and accelerated neurogenesis after ICH. This study demonstrated for the first time that minocycline promoted M2 microglia polarization via upregulation of the TrkB/BDNF pathway and promoted neurogenesis after ICH. This study contributes to our understanding of the therapeutic potential of minocycline in ICH. NEW & NOTEWORTHY The present study gives several novel points: 1) Minocycline promotes neurogenesis after intracerebral hemorrhage in rats. 2) Minocycline induces activated M1 microglia into M2 neurotrophic phenotype. 3) M2 microglia secreting BDNF remodel the damaged neurocircuit.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hemorragia Cerebral/prevenção & controle , Microglia/efeitos dos fármacos , Minociclina/administração & dosagem , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Receptor trkB/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Hemorragia Cerebral/fisiopatologia , Proteína Duplacortina , Aprendizagem em Labirinto/efeitos dos fármacos , Microglia/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
9.
Biomed Mater ; 10(1): 015019, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25668049

RESUMO

To investigate the potential application of graphene oxide (GO) in bone repair, this study is focused on the preparation, characterization and cell behavior of graphene oxide coatings on quartz substrata. GO coatings were prepared on the substrata using a modified dip-coating procedure. Atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman spectroscopy results demonstrated that the as-prepared coatings in this study were homogeneous and had an average thickness of ~67 nm. The rapid formation of a hydroxyapatite (HA) layer in the simulated body fluid (SBF) on GO coated substrata at day 14, as proved by SEM and x-ray diffraction (XRD), strongly indicated the bioactivity of coated substrata. In addition, MC3T3-E1 cells were cultured on the coated substrata to evaluate cellular activities. Compared with the non-coated substrata and tissue culture plates, no significant difference was observed on the coated substrata in terms of cytotoxicity, viability, proliferation and apoptosis. However, interestingly, higher levels of alkaline phosphatase (ALP) activity and osteocalcin (OC) secretion were observed on the coated substrata, indicating that GO coatings enhanced cell differentiation compared with non-coated substrata and tissue culture plates. This study suggests that GO coatings had excellent biocompatibility and more importantly promoted MC3T3-E1 cell differentiation and might be a good candidate as a coating material for orthopedic implants.


Assuntos
Materiais Biocompatíveis/química , Durapatita/química , Grafite/química , Ortopedia , Óxidos/química , Células 3T3 , Fosfatase Alcalina/química , Animais , Apoptose , Líquidos Corporais/química , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Meios de Cultura/química , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Osteocalcina/química , Quartzo , Sincalida/química , Análise Espectral Raman , Propriedades de Superfície , Difração de Raios X
10.
Eur J Ophthalmol ; 20(4): 719-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20099237

RESUMO

PURPOSE: Accumulating evidence indicates that oxidative stress may play an important role in the pathogenesis of type 2 diabetes and its complications. Lycopene, a very potent antioxidant of carotenoids, has received considerable scientific interest in recent years for its potential role in the prevention of oxidative stress-related chronic diseases. This study was undertaken to investigate whether the serum levels of lycopene are altered between type 2 diabetic patients with and without diabetic retinopathy. METHODS: A total of 71 patients with type 2 diabetes were analyzed and compared with 23 nondiabetic healthy controls. Serum lycopene concentrations were assayed using high-performance liquid chromatography. RESULTS: Lycopene level was found to be significantly lower in diabetic patients than in controls (p = 0.021). In the diabetic group, subjects with proliferative diabetic retinopathy had significantly lower lycopene levels than subjects without diabetic retinopathy or with nonproliferative diabetic retinopathy. In the analysis of correlations, hemoglobin A1c were negatively correlated with lycopene (r = -0.345, p = 0.007) after multivariate adjustment. A stepwise linear multiple regression model revealed that age and hemoglobin A1c were significant determinants of lycopene. CONCLUSIONS: Our findings show that measuring serum lycopene is a novel convenient method for evaluating oxidative damage. Diabetic patients, especially those with advanced diabetic retinopathy, had significantly lower serum lycopene levels; this suggests that lycopene may be helpful for the diagnosis, severity, and therapeutic evaluation of diabetic retinopathy.


Assuntos
Carotenoides/sangue , Retinopatia Diabética/sangue , Estresse Oxidativo/fisiologia , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Tipo 2/sangue , Progressão da Doença , Feminino , Humanos , Licopeno , Masculino , Pessoa de Meia-Idade , Prognóstico
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