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1.
Am J Ophthalmol ; 262: 237-245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38452920

RESUMO

PURPOSE: To investigate the relationship between effective lens position (ELP) and patient characteristics, and to further develop a new intraocular lens (IOL) calculation formula for cataract patients with previous pars plana vitrectomy (PPV). DESIGN: Cross-sectional study. METHODS: A total of 2793 age-related cataract patients (group 1) and 915 post-PPV cataract patients (group 2) who underwent phacoemulsification with IOL implantation were included. The ELP of 2 groups was compared and the association between ELP and patient characteristics was further evaluated using standardized multivariate regression coefficients. An ensemble artificial intelligence-based ELP prediction model was developed using a training set of 810 vitrectomized eyes, and a thick-lens IOL formula (LISA-PPV) was constructed and compared with 7 existing formulas on an external multi-center testing set of 105 eyes. RESULTS: Compared to eyes with age-related cataract, vitrectomized eyes showed a similar ELP distribution (P = .19), but different standardized coefficients of preoperative biometry for ELP. The standardized coefficients also varied with the type of vitreous tamponade, history of scleral buckling, and ciliary sulcus IOL implantation. The LISA-PPV formula showed the lowest mean and median absolute prediction error (MAE: 0.63 D; MedAE: 0.44 D), and the highest percentages of eyes within ±0.5 D of prediction error (57.14%) in the testing dataset. CONCLUSIONS: The ELP prediction required optimization specifically for vitrectomized eyes based on their biometric and surgical characteristics. The LISA-PPV formula is a useful and accurate tool for determining IOL power in cataract patients with previous PPV (available at http://ppv-iolcalculator.com/).


Assuntos
Inteligência Artificial , Biometria , Implante de Lente Intraocular , Lentes Intraoculares , Óptica e Fotônica , Facoemulsificação , Vitrectomia , Humanos , Estudos Transversais , Masculino , Feminino , Idoso , Vitrectomia/métodos , Biometria/métodos , Pessoa de Meia-Idade , Acuidade Visual/fisiologia , Idoso de 80 Anos ou mais , Refração Ocular/fisiologia , Catarata/fisiopatologia , Catarata/complicações , Estudos Retrospectivos
2.
BMC Ophthalmol ; 23(1): 332, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474888

RESUMO

BACKGROUND: To evaluate the influence of decentration of plate-haptic toric intraocular lens (IOLs) on visual quality. METHODS: This study enrolled 78 eyes of 78 patients. Patients in group A were implanted with toric IOLs, and patients in group B were implanted with monofocal IOLs. All patients were divided into group A1 and B1 (decentration below 0.3 mm) and group A2 and B2 (decentration above 0.3 mm). The uncorrected distance visual acuity (UDVA), best corrected visual acuity (BCVA), modulation transfer function cutoff (MTF cutoff), objective scatter index (OSI), strehl ratio (SR), optical interference and patients' satisfaction were measured in different pupils at three months postoperatively. The associations between decentration and visual quality were analyzed by Spearman correlation. RESULTS: There were no significant differences in UDVA, BCVA, MTF cutoff, OSI, SR, optical interference and patients' satisfaction among subgroups. The differences in decentration between groups A and B were not statistically significant. In group A2, the total higher order aberrations (tHOAs) at pupil sizes of 3 mm (P = 0.046), 5 mm (P = 0.014), spherical aberrations at pupil sizes of 3 mm (P = 0.011), 4 mm (P = 0.014), 5 mm (P = 0.000), secondary astigmatism at pupil sizes of 3 mm (P = 0.002), 4 mm (P = 0.005) were higher than in group B2. Compared to group A1, group A2 had higher spherical aberrations at pupil sizes of 4 mm (P = 0.042), 5 mm (P = 0.001), 6 mm (P = 0.038), secondary astigmatism at pupil sizes of 3 mm (P = 0.013), 4 mm (P = 0.005), 6 mm (P = 0.013). Group B2 has higher coma and secondary astigmatism than group B1 at 6-mm pupil (P = 0.014, P = 0.045). Significant positive correlations were found between spherical aberrations and the decentration of group A1 and A2 at 6-mm pupils. CONCLUSION: The decentration above 0.3 mm negatively affected visual quality due to increased tHOAs, spherical aberrations, coma and secondary astigmatism aberrations, the influence become larger with increasing pupil diameter. And toric IOLs are more affected by decentration than monofocal IOLs.


Assuntos
Astigmatismo , Lentes Intraoculares , Facoemulsificação , Humanos , Implante de Lente Intraocular , Astigmatismo/cirurgia , Astigmatismo/complicações , Coma/complicações , Coma/cirurgia , Tecnologia Háptica
3.
Biomed Pharmacother ; 165: 115052, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37399715

RESUMO

Reactive oxygen species (ROS) overproduction plays an essential role in the etiology of ischemic/hypoxic retinopathy caused by acute glaucoma. NADPH oxidase (NOX) 4 was discovered as one of the main sources of ROS in glaucoma. However, the role and potential mechanisms of NOX4 in acute glaucoma have not been fully elucidated. Therefore, the current study aims to investigate the NOX4 inhibitor GLX351322 that targets NOX4 inhibition in acute ocular hypertension (AOH)-induced retinal ischemia/hypoxia injury in mice. Herein, NOX4 was highly expressed in AOH retinas, particularly the retinal ganglion cell layer (GCL). Importantly, the NOX4 inhibitor GLX351322 reduced ROS overproduction, inhibited inflammatory factor release, suppressed glial cell activation and hyperplasia, inhibited leukocyte infiltration, reduced retinal cell senescence and apoptosis in damaged areas, reduced retinal degeneration and improved retinal function. This neuroprotective effect is at least partially associated with mediated redox-sensitive factor (HIF-1α, NF-κB, and MAPKs) pathways by NOX4-derived ROS overproduction. These results suggest that inhibition of NOX4 with GLX351322 attenuated AOH-induced retinal inflammation, cellular senescence, and apoptosis by inhibiting the activation of the redox-sensitive factor pathway mediated by ROS overproduction, thereby protecting retinal structure and function. Targeted inhibition of NOX4 is expected to be a new idea in the treatment of acute glaucoma.


Assuntos
Glaucoma , Hipertensão Ocular , Doenças Retinianas , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , NADPH Oxidase 4/metabolismo , Doenças Retinianas/tratamento farmacológico , Glaucoma/complicações , Glaucoma/tratamento farmacológico , Hipertensão Ocular/complicações , Hipertensão Ocular/tratamento farmacológico , Oxirredução , Inflamação/tratamento farmacológico , NADPH Oxidases/metabolismo
4.
ACS Appl Mater Interfaces ; 14(49): 55130-55142, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36448296

RESUMO

Polymer-based dielectric nanocomposites have attracted great attention due to the advantages of high-power density and stability. However, due to the limited breakdown strength (Eb) of the dielectrics, the unsatisfactory energy density becomes the bottleneck that restricts their applications. Here, newly designed sandwich-structured nanocomposites are proposed, which includes the introduction of low-loading 0.4BiFeO3-0.6SrTiO3 (BFSTO) nanofibers into the poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) matrix as the polarization layer (B-layer) to offer high permittivity and the selection of poly(methylmethacrylate) (PMMA)/P(VDF-HFP) all-organic blend film as the insulation layer (P-layer) to improve Eb of the nanocomposites. The optimized sandwich-structured PBP nanocomposite exhibits significant enhancement in Eb (668.6 MV/m), generating a discharged energy density of 17.2 J/cm3. The dielectric and Kelvin probe force microscope results corroborate that the outer P-layer has a low surface charge density, which can markedly impede the charge injection from the electrode/dielectric interface and thereby suppress the leakage current inside the nanocomposite. Furthermore, both the finite element simulations and capacitive series models demonstrate that the homogenized distribution of electric field in the PBP sandwich-structured nanocomposite favors the improvement of energy storage performance. This work not only provides insightful guidance into the in-depth understanding of the dielectric breakdown mechanism in sandwich-structured nanocomposites but also offers a novel paradigm for the development of polymer-based nanocomposites with high Eb and discharged energy density.

5.
PLoS One ; 16(6): e0252653, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34081736

RESUMO

PURPOSE: Infiltration of activated dendritic cells and inflammatory cells in cornea represents an important marker for defining corneal inflammation. Deep transfer learning has presented a promising potential and is gaining more importance in computer assisted diagnosis. This study aimed to develop deep transfer learning models for automatic detection of activated dendritic cells and inflammatory cells using in vivo confocal microscopy images. METHODS: A total of 3453 images was used to train the models. External validation was performed on an independent test set of 558 images. A ground-truth label was assigned to each image by a panel of cornea specialists. We constructed a deep transfer learning network that consisted of a pre-trained network and an adaptation layer. In this work, five pre-trained networks were considered, namely VGG-16, ResNet-101, Inception V3, Xception, and Inception-ResNet V2. The performance of each transfer network was evaluated by calculating the area under the curve (AUC) of receiver operating characteristic, accuracy, sensitivity, specificity, and G mean. RESULTS: The best performance was achieved by Inception-ResNet V2 transfer model. In the validation set, the best transfer system achieved an AUC of 0.9646 (P<0.001) in identifying activated dendritic cells (accuracy, 0.9319; sensitivity, 0.8171; specificity, 0.9517; and G mean, 0.8872), and 0.9901 (P<0.001) in identifying inflammatory cells (accuracy, 0.9767; sensitivity, 0.9174; specificity, 0.9931; and G mean, 0.9545). CONCLUSIONS: The deep transfer learning models provide a completely automated analysis of corneal inflammatory cellular components with high accuracy. The implementation of such models would greatly benefit the management of corneal diseases and reduce workloads for ophthalmologists.


Assuntos
Córnea/diagnóstico por imagem , Aprendizado Profundo , Microscopia Confocal/métodos , Área Sob a Curva , Células Dendríticas/citologia , Células Dendríticas/imunologia , Diagnóstico por Computador , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/diagnóstico por imagem , Humanos , Ceratite/diagnóstico , Ceratite/diagnóstico por imagem , Modelos Teóricos , Oftalmologistas/psicologia , Pterígio/diagnóstico , Pterígio/diagnóstico por imagem , Curva ROC , Sensibilidade e Especificidade
6.
ACS Nano ; 14(8): 10723-10732, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32806032

RESUMO

Ferroelectric materials have drawn widespread attention due to their switchable spontaneous polarization and anomalous photovoltaic effect. The coupling between ferroelectricity and the piezo-phototronic effect may lead to the design of distinctive photoelectric devices with multifunctional features. Here, we report an enhancement of the photovoltaic performances in the ferroelectric p-type La-doped bismuth ferrite film (BLFO)/n-type zinc oxide (ZnO) nanowire array heterojunction by rationally coupling the strain-induced piezoelectricity in ZnO nanowires and the ferroelectricity in BLFO. Under a compressive strain of -2.3% and a 10 V upward poling of the BLFO, the open-circuit voltage (VOC) and short-circuit current density (JSC) of the device increase by 8.4% and 54.7%, respectively. Meanwhile, the rise (/decay) time is modulated from 153.7 (/108.8) to 61.28 (/74.86) ms. Systematical band diagram analysis reveals that the promotion of photogenerated carriers and boost of the photovoltaic performances of the device can be attributed to the modulated carrier transport behaviors at the BLFO/ZnO interface and the superposed driving forces arising from the adding up of the piezoelectric potential and ferroelectric polarization. In addition, COMSOL simulation results of piezopotential distribution in ZnO nanowire arrays and the energy band structure change of the heterojunction further confirm the mechanisms. This work not only presents an approach to design high-performance ferroelectric photovoltaic devices but also further broadens the research scope of piezo-phototronics.

7.
Materials (Basel) ; 11(11)2018 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-30373246

RESUMO

The electrochemical behaviors of Al(III) deposits on Ni substrates were investigated in LiCl-KCl-AlCl3 (2 wt.%) molten salts. Various electrochemical methods, including cyclic voltammetry (CV), square wave voltammetry (SWV), and open circuit chronopotentiometry (OCP) were used to explore the deposition processes of Al(III) on Ni substrates. Five kinds of Al-Ni alloys phase were firstly electrodeposited by the regulation of deposition potential form LiCl-KCl-AlCl3 (2 wt.%) molten salts at 753 K. The formation of Al-Ni alloys, such as AlNi3, Ni5Al3, AlNi, Al3Ni2, and Al3Ni were confirmed by X-ray diffractometer (XRD) and the cross-section morphologies were investigated by scanning electron microscope (SEM). Meanwhile, it was found that the temperature of molten salt was another key parameter for the controlling of alloys phase. No Al-Ni alloys phase other than AlNi3 and Ni5Al3 could be deposited at 703 K.

8.
Nanoscale Res Lett ; 11(1): 295, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27299650

RESUMO

SnO2 nanosheet-structured films were prepared on a fluorine-doped tin oxide (FTO) substrate using ZnO nanosheet as template. The as-prepared SnO2 nanosheets contained plenty of nano-voids and were generally vertical to the substrate. TiO2 nanoparticles were homogeneously deposited into the intervals between the SnO2 nanosheets to prepare a hierarchically structured SnO2/TiO2 hybrid film. The hybrid films were co-sensitized with CdS and CdSe quantum dots. The sensitized solar cells assembled with the SnO2/TiO2 hybrid film showed much higher photoelectricity conversion efficiency than the cells assembled with pure TiO2 films. The lifetime of photoinduced electron was also investigated through electrochemical impedance spectroscopy, which showed that the SnO2/TiO2 hybrid film electrode is as long as the TiO2 film electrode.

9.
Phys Chem Chem Phys ; 14(23): 8376-81, 2012 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-22588092

RESUMO

BiFeO(3) (BFO) microspheres were synthesized by a facile hydrothermal method. The optical absorption spectrum indicates that on site Fe(3+) crystal-field transitions and the charge transfer excitations can be observed. Magnetic measurements show a spin-glass behavior and room temperature weak ferromagnetism. The surface photovoltage spectroscopy of the BFO shows two response peaks centered at about 370 and 400 nm, respectively. Under an ambient atmosphere, the maximum surface photovoltage of the BFO reaches 180 µV with the bias (+2 V) and is three times larger than that with zero bias. It is found that the surface photovoltage response intensity increases with an increase in applied bias, regardless of positive or negative bias. It is suggested that the surface photovoltaic properties are related to both the depolarization field owing to ferroelectric polarization and the build-in electric field due to the Schottky barrier. The micro-process and the physical mechanism of the separation of photogenerated charges for BFO are fully explained.

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