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1.
Ocul Surf ; 34: 124-131, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033974

RESUMEN

Breast cancer is the most prevalent cancer worldwide. With advancements in breast cancer diagnosis and treatment, the prognosis of patients with early-stage cancer has significantly improved. Enhancing the long-term quality of life of patients after antineoplastic therapy, including visual quality, has become a crucial research focus. This review aims to comprehensively summarize dry eye disease adverse reaction resulting from pharmacotherapy for early-stage breast cancer. Through a review of the relevant literature, this study explored the etiology, clinical features, and potential therapeutic strategies for drug-induced dry eye disease in breast cancer treatment. A thorough understanding of the medication-induced dry eye disease adverse reaction aid clinicians in monitoring and managing patients' ocular health more effectively, facilitating early diagnosis and intervention, preventing complications, and ensuring optimal visual protection for patients undergoing breast cancer treatment.

2.
J Mol Histol ; 55(4): 455-464, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38877338

RESUMEN

The Omi/HtrA2 inhibitor 5-[5-(2-nitrophenyl) furfuryliodine]-1,3-diphenyl-2-thiobarbituric acid (Ucf-101) has shown neuroprotective effects in the central nervous system. However, whether Ucf-101 can protect retinal ganglion cells (RGCs) after retinal ischemia/reperfusion (IR) has not been investigated. We aimed to investigate the effects of Ucf-101 on RGCs apoptosis and inflammation after IR-induced retinal injury in mice. We injected Ucf-101 into the mouse vitreous body immediately after IR injury. After 7 days, hematoxylin and eosin staining was conducted to assess retinal tissue damage. Next, retrograde labeling with FluoroGold, counting of RGCs and TUNEL staining were conducted to evaluate apoptosis. Immunohistochemistry, immunofluorescence staining, and western blotting were conducted to analyze protein levels. IR injury-induced retinal tissue damage could be prevented by Ucf-101 treatment. The number of TUNEL-positive RGCs was reduced by Ucf-101 treatment in mice with IR injury. Ucf-101 treatment inhibited the upregulation of Bax, cleaved caspase-3 and cleaved caspase-9 and activated the JNK/ERK/P38 signaling pathway. Furthermore, Ucf-101 treatment inhibited the upregulation of glial fibrillary acidic protein (GFAP), vimentin, Iba1 and CD68 in mice with IR injury. Ucf-101 prevents retinal tissue damage, improves the survival of RGCs, and suppresses microglial overactivation after IR injury. Ucf-101 might be a potential target to prevent RGCs apoptosis and inflammation in neurodegenerative eye diseases.


Asunto(s)
Apoptosis , Estrés Oxidativo , Daño por Reperfusión , Células Ganglionares de la Retina , Animales , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Ratones , Estrés Oxidativo/efectos de los fármacos , Apoptosis/efectos de los fármacos , Masculino , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/efectos de los fármacos , Ratones Endogámicos C57BL , Inflamación/patología , Inflamación/metabolismo , Tiobarbitúricos/metabolismo , Retina/metabolismo , Retina/patología , Furanos/farmacología , Retinitis/etiología , Retinitis/patología , Retinitis/metabolismo , Modelos Animales de Enfermedad , Pirimidinonas , Tionas
3.
Case Rep Ophthalmol ; 15(1): 170-175, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38433780

RESUMEN

Introduction: Prolonged exposure to a complete button battery can cause severe tissue necrosis in the eye and permanent impairment of visual function. The main mechanism of injury is the current generated by the hydrolysis of tissue fluid at the negative electrode and the production of hydroxide ions. Case Presentation: A 3-year-old girl went to the local hospital because of swelling and pain in her right eye of 12-h duration. The local doctor performed an orbital CT (computed tomography) scan and found a foreign body between the right eyelid and the eyeball. The foreign body was removed immediately under general anesthesia. In addition, it was found that the foreign body was a button battery, but it prolonged 39 h from the onset of the child's symptoms. The child underwent a second operation in our hospital and received amniotic membrane transplantation combined with conjunctival flap coverage. Topical corticosteroid and antibiotic eye ointment were continued for 3 months after surgery. Local pigmentation was seen, there was no symblepharon, but the cornea was still opaque and the visual acuity was only FC (finger count). In this particular case, heavy metal testing conducted on the child's blood fortunately revealed that the levels were within the normal range. Conclusion: Early detection and urgent removal of button battery are crucial in order to minimize exposure time. We should also be concerned about heavy metals in the blood. Children should be kept away from button batteries as much as possible to avoid such injury.

4.
Ann Med ; 55(2): 2258894, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37734409

RESUMEN

OBJECTIVE: To compare the postoperative binocular visual quality in six treatment protocols for bilateral age-related cataract surgery with presbyopia correction for clinical decisions. MATERIALS AND METHODS: In this prospective two-center single-blinded cohort study, participants from North or South China who underwent bilateral phacoemulsification and intraocular lens implantation were divided into six protocols: monovision, diffractive bifocal, mixed, refractive bifocal, trifocal, and micro-monovision extended range of vision (EROV). Binocular visual quality was evaluated at 3 months postoperatively, including binocular uncorrected full-range visual acuity, binocular defocus curves (depth of focus [DoF] and area under the curve [AUC]), binocular visual function (fusion function and stereopsis), binocular subjective spectacle independence rates, visual analog scale (VAS) of overall satisfaction, 25-item visual function questionnaire (VFQ-25), and binocular dysphotopsia symptoms. RESULTS: Of the 300 enrolled patients, 272 (90.7%; 544 eyes) were analyzed. The trifocal protocol showed excellent binocular full-range visual acuity and the best performance for most DoFs and AUCs. The monovision protocol presented the worst binocular visual quality in most perspectives, especially in convergence, distance, and near stereopsis (p < 0.001). The full-range subjective spectacle independence rates were sorted from highest to lowest as follows: trifocal (84.8%), refractive bifocal (80.9%), EROV (80.0%), mixed (73.3%), diffractive bifocal (65.2%), and monovision (32.6%) protocols, with no statistically significant differences between the former five protocols (p > 0.05). The EROV protocol achieved the highest VAS and VFQ-25 scores. The incidence of postoperative binocular dysphotopsia symptoms was comparable in all protocols. CONCLUSIONS: The trifocal protocol showed the best performance, and the monovision protocol presented the worst performance in most perspectives of binocular visual quality for presbyopia correction. The refractive bifocal, mixed, or EROV protocols can provide an approximate performance as a trifocal protocol. Ophthalmologists can customize therapies using different protocols.


Asunto(s)
Catarata , Presbiopía , Humanos , Presbiopía/cirugía , Estudios de Cohortes , Estudios Prospectivos , Catarata/complicaciones , Protocolos Clínicos , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
BMC Ophthalmol ; 23(1): 332, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474888

RESUMEN

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.


Asunto(s)
Astigmatismo , Lentes Intraoculares , Facoemulsificación , Humanos , Implantación de Lentes Intraoculares , Astigmatismo/cirugía , Astigmatismo/complicaciones , Coma/complicaciones , Coma/cirugía , Tecnología Háptica
6.
Biomed Pharmacother ; 165: 115052, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37399715

RESUMEN

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.


Asunto(s)
Glaucoma , Hipertensión Ocular , Enfermedades de la Retina , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , NADPH Oxidasa 4/metabolismo , Enfermedades de la Retina/tratamiento farmacológico , Glaucoma/complicaciones , Glaucoma/tratamiento farmacológico , Hipertensión Ocular/complicaciones , Hipertensión Ocular/tratamiento farmacológico , Oxidación-Reducción , Inflamación/tratamiento farmacológico , NADPH Oxidasas/metabolismo
7.
Transl Vis Sci Technol ; 12(4): 8, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-37026984

RESUMEN

Purpose: Accurate identification of corneal layers with in vivo confocal microscopy (IVCM) is essential for the correct assessment of corneal lesions. This project aims to obtain a reliable automated identification of corneal layers from IVCM images. Methods: A total of 7957 IVCM images were included for model training and testing. Scanning depth information and pixel information of IVCM images were used to build the classification system. Firstly, two base classifiers based on convolutional neural networks and K-nearest neighbors were constructed. Second, two hybrid strategies, namely weighted voting method and light gradient boosting machine (LightGBM) algorithm were used to fuse the results from the two base classifiers and obtain the final classification. Finally, the confidence of prediction results was stratified to help find out model errors. Results: Both two hybrid systems outperformed the two base classifiers. The weighted area under the curve, weighted precision, weighted recall, and weighted F1 score were 0.9841, 0.9096, 0.9145, and 0.9111 for weighted voting hybrid system, and were 0.9794, 0.9039, 0.9055, and 0.9034 for the light gradient boosting machine stacking hybrid system, respectively. More than one-half of the misclassified samples were found using the confidence stratification method. Conclusions: The proposed hybrid approach could effectively integrate the scanning depth and pixel information of IVCM images, allowing for the accurate identification of corneal layers for grossly normal IVCM images. The confidence stratification approach was useful to find out misclassification of the system. Translational Relevance: The proposed hybrid approach lays important groundwork for the automatic identification of the corneal layer for IVCM images.


Asunto(s)
Córnea , Trastornos de la Visión , Humanos , Córnea/diagnóstico por imagen , Trastornos de la Visión/patología , Algoritmos , Microscopía Confocal/métodos , Redes Neurales de la Computación
8.
Int Ophthalmol ; 43(7): 2203-2214, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36595127

RESUMEN

PURPOSE: Fungal keratitis is a common cause of blindness worldwide. Timely identification of the causative fungal genera is essential for clinical management. In vivo confocal microscopy (IVCM) provides useful information on pathogenic genera. This study attempted to apply deep learning (DL) to establish an automated method to identify pathogenic fungal genera using IVCM images. METHODS: Deep learning networks were trained, validated, and tested using a data set of 3364 IVCM images that collected from 100 eyes of 100 patients with culture-proven filamentous fungal keratitis. Two transfer learning approaches were investigated: one was a combined framework that extracted features by a DL network and adopted decision tree (DT) as a classifier; another was a complete supervised DL model which used DL-based fully connected layers to implement the classification. RESULTS: The DL classifier model revealed better performance compared with the DT classifier model in an independent testing set. The DL classifier model showed an area under the receiver operating characteristic curves (AUC) of 0.887 with an accuracy of 0.817, sensitivity of 0.791, specificity of 0.831, G-mean of 0.811, and F1 score of 0.749 in identifying Fusarium, and achieved an AUC of 0.827 with an accuracy of 0.757, sensitivity of 0.756, specificity of 0.759, G-mean of 0.757, and F1 score of 0.716 in identifying Aspergillus. CONCLUSION: The DL model can classify Fusarium and Aspergillus by learning effective features in IVCM images automatically. The automated IVCM image analysis suggests a noninvasive identification of Fusarium and Aspergillus with clear potential application in early diagnosis and management of fungal keratitis.


Asunto(s)
Úlcera de la Córnea , Infecciones Fúngicas del Ojo , Queratitis , Humanos , Inteligencia Artificial , Úlcera de la Córnea/diagnóstico , Queratitis/diagnóstico , Queratitis/microbiología , Hongos , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Microscopía Confocal/métodos
9.
NanoImpact ; 29: 100449, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36610662

RESUMEN

Macro- or micro-nutrients are essential for crop yield and nutritional quality. In this work, selenium engineering nanomaterials (Se ENMs, 0.5 mg‧kg-1) significantly increased the yield and nutritional quality of lettuce, which was better than that of selenite (Na2SeO3). Under the treatment of Se ENMs, macro-nutrients including nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were increased by 15.8%, 98.5%, 42.8%, 146.9%, and 62.5%, respectively, and micro-nutrients including manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn) were also increased by 87.4%, 78.0%, 61.1%, and 56.1%, respectively. As a result, the improved nutritional status of lettuce leaves increased photosynthesis (59.2%) and yield (37.6%). Root diameters and root tips of lettuce were increased by 23.9% and 18.6%, respectively, upon exposure to Se ENMs, which may be responsible for facilitating the absorption of macro and micro nutrients from the soil. These effects were significantly better than SeO32- treated group. Metabolome results indicated that Se ENMs could improve the shikimic acid, phenylalanine, and tyrosine pathway, resulting in an enhancement of the beneficial compounds, including quercetin, rutin, and coumarin, by 2.9, 2.7, and 2.4-fold, respectively. Besides, pyruvic acid and TCA cycle were also improved by Se ENMs. These results provide new insight into the positive effect of Se ENMs on crop yield and nutritional quality, which demonstrate that the Se ENMs-enabled agriculture practices have a promising prospect as a sustainable crop strategy.


Asunto(s)
Nanoestructuras , Selenio , Selenio/metabolismo , Lactuca , Fotosíntesis , Nutrientes
10.
Angew Chem Int Ed Engl ; 62(6): e202210485, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36329001

RESUMEN

Conventional methods for fabricating multilayered ceramic membranes with ion conducting dense thin layers are often cumbersome, costly, and limited by poor adhesion between layers. Inspired by the architectural structure of the rooted grasses in soil, here, we report an interface-reaction-induced reassembly approach for the direct fabrication of Ce0.9 Gd0.1 O2-δ (CGO) thin layers rooted in the parent multilayered ceramic membranes by only one firing step. The CGO dense layers are very thin, and adhered strongly to the parent support layer, ensuring low ionic transport resistance and structural integrity of the multilayered membranes. When using as an oxygen permeable membrane for upgrading fossil-fuel-derived hydrogen, it shows very long durability in harsh conditions containing H2 O, CH4 , H2 , CO2 and H2 S. Furthermore, our approach is highly scalable and applicable to a wide variety of ion conducting thin layers, including Y0.08 Zr0.92 O2-δ , Ce0.9 Sm0.1 O2-δ and Ce0.9 Pr0.1 O2-δ .

11.
BMC Ophthalmol ; 22(1): 407, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36266642

RESUMEN

BACKGROUND: To assess and compare the efficacy, safety, accuracy, predictability and visual quality of a diffractive trifocal intraocular lens (IOL) and a refractive rotationally asymmetric bifocal IOL in eyes with axial myopia. METHODS: This prospective cohort study enrolled patients with implantation of the diffractive trifocal IOL or the refractive bifocal IOL. Eyes were divided into four groups according to the IOL implanted and axial length. Manifest refraction, uncorrected and corrected visual acuity at far, intermediate and near distances, prediction error of spherical equivalent (SE), contrast sensitivity and aberrations were evaluated three months after surgery. RESULTS: In total, 80 eyes of 80 patients were included: 20 eyes in each group. Three months postoperatively, the corrected distance visual acuity of two trifocal groups were significantly better than the axial myopia bifocal group (P = 0.007 and 0.043). There was no significant difference of postoperative SE (P = 0.478), but the SE predictability of the trifocal IOL was better, whether in axial myopia groups (P = 0.015) or in control groups (P = 0.027). The contrast sensitivity was similar among four groups. The total aberration, higher order aberration and trefoil aberration of bifocal groups were significantly higher (all P < 0.001). CONCLUSIONS: The diffractive trifocal IOL and the refractive bifocal IOL both provided good efficacy, accuracy, predictability and safety for eyes with axial myopia. By contrast, the trifocal IOL had a better performance in corrected distance visual acuity and visual quality. TRIAL REGISTRATION: The study was retrospectively registered and posted on clinicaltrials.gov at 12/02/2020 (NCT04265846).


Asunto(s)
Lentes Intraoculares , Miopía , Facoemulsificación , Humanos , Implantación de Lentes Intraoculares , Estudios Prospectivos , Refracción Ocular , Diseño de Prótesis , Miopía/cirugía , Satisfacción del Paciente
12.
Front Med (Lausanne) ; 9: 980110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36117984

RESUMEN

Purpose: To compare the presbyopia-correcting performance, visual quality, satisfaction and life quality after implantation of a diffractive trifocal intraocular lens (IOL) in eyes with different axial lengths (AL). Methods: This prospective cohort study enrolled patients with implantation of a trifocal IOL. Manifest refraction, uncorrected and distance-corrected visual acuity at different distances, contrast sensitivity, aberrations and IOL decentration were measured 3 months after surgery. Spectacle independence, adverse photic phenomena, overall satisfaction and life quality were assessed with a questionnaire. Results: This study included 61 eyes of 61 patients: 16 eyes in the short AL group, 28 eyes in the control group and 17 eyes in the long AL group. Postoperatively, the prediction error (PE) of spherical equivalent showed a difference (P = 0.002). The uncorrected near visual acuity in the long AL group was higher (P = 0.047). Although a higher IOL decentration was obtained in the long AL group (P = 0.034), no significant difference was found in contrast sensitivity and aberrations (all P > 0.05). In the questionnaire, patients in the long AL group showed a relatively lower spectacle independence at near distance (P = 0.060) and had difficulties in near activities, mental health and role in daily life (P = 0.003, 0.021, and 0.033). However, no significant difference was observed in overall satisfaction (P = 0.124). Conclusion: With detailed preoperative evaluation, the trifocal IOL provided satisfactory visual outcomes for patients with different AL. AL had a certain influence on predictability and IOL decentration. And for patients with long AL, the inadaptability to the near focal point might become an important problem.

13.
Ophthalmol Ther ; 11(6): 2067-2082, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36071311

RESUMEN

INTRODUCTION: The aim of this study was to explore a method to rank the cost-effectiveness of presbyopia correction in diverse strategies of bilateral cataract surgery to provide references for healthcare policymakers in rationalizing resource utilization and surgeons in customizing patient management. METHODS: The cost-effectiveness analysis based on a prospective single-blind two-center clinical trial included seven strategies in bilateral cataract surgery: monofocal, monovision, diffractive bifocal, blended, refractive bifocal, trifocal, and extended depth of focus (EDOF) strategies. The effectiveness according to the objective spectacle independence rate (hereafter "rate", a novel indicator defined as the proportion of patients with binocular uncorrected distance, intermediate and near visual acuity all better than 0.1 logMAR, logarithm of the minimum angle of resolution), costs, average cost-effectiveness ratios (ACERs, $/1% rate), and incremental cost-effectiveness ratios (ICERs, $/1% incremental rate) were estimated. RESULTS: In 194 participants (388 eyes), the trifocal strategy achieved the highest rate [93.10% (95% confidence interval (CI) 83.8-102.35%)]. The refractive bifocal strategy had the minimum ACER [$45.54/1% rate (95% CI 34.57-56.50)], followed by the blended [$59.10/1% rate (95% CI 31.72-86.48)], diffractive bifocal [$69.06/1% rate (95% CI 30.89-107.21)], EDOF [$72.85/1% rate (95% CI 52.02-93.70)], trifocal [$93.01/1% rate (95% CI 83.23-102.79)], monovision [$136.83/1% rate (95% CI - 55.40 to 329.14)], and monofocal [$264.45/1% rate (95% CI - 97.45 to 626.55)] strategies. Compared with the refractive bifocal strategy, the probabilities that the trifocal strategy (ICER $289.74/1% incremental rate) is very cost-effective and cost-effective were 81.7% and 93.2%, respectively, at the wiliness-to-pay threshold of one and three times China's annual disposable income per capita in 2021 per 10% incremental rates. CONCLUSIONS: Cost-effectiveness analysis with ACER and ICER according to objective spectacle independence rate is a helpful tool to identify highly cost-effective presbyopia-correcting strategies in cataract surgery for clinical and policy decisions. TRIAL REGISTRATION: Clinicaltrials.gov (NCT04265846).

14.
Nano Lett ; 22(17): 6936-6941, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36041122

RESUMEN

Metal oxide nanoparticles exhibit outstanding catalytic properties, believed to be related to the presence of oxygen vacancies at the particle's surface. However, little quantitative information is known about concentrations of point defects inside and at surfaces of these nanoparticles, due to the challenges in achieving an atomically resolved experimental access. By employing off-axis electron holography, we demonstrate, using MgO nanoparticles as an example, a methodology that discriminates between mobile charge induced by electron beam irradiation and immobile charge associated with deep traps induced by point defects as well as distinguishes between bulk and surface point defects. Counting the immobile charge provides a quantification of the concentration of F2+ centers induced by oxygen vacancies at the MgO nanocube surfaces.


Asunto(s)
Holografía , Nanopartículas del Metal , Electrones , Holografía/métodos , Óxido de Magnesio , Óxidos , Oxígeno
15.
Phys Rev Lett ; 129(5): 057201, 2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35960587

RESUMEN

We report a magnetic transition region in La_{0.7}Sr_{0.3}MnO_{3} with gradually changing magnitude of magnetization, but no rotation, stable at all temperatures below T_{C}. Spatially resolved magnetization, composition and Mn valence data reveal that the magnetic transition region is induced by a subtle Mn composition change, leading to charge transfer at the interface due to carrier diffusion and drift. The electrostatic shaping of the magnetic transition region is mediated by the Mn valence, which affects both magnetization by Mn^{3+}-Mn^{4+} double exchange interaction and free carrier concentration.


Asunto(s)
Magnetismo , Electricidad Estática , Temperatura
16.
iScience ; 25(4): 104047, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35359811

RESUMEN

Magnetic high-entropy alloys (HEAs) are a new category of high-performance magnetic materials, with multicomponent concentrated compositions and complex multi-phase structures. Although there have been numerous reports of their interesting magnetic properties, there is very limited understanding about the interplay between their hierarchical multi-phase structures and the resulting magnetic behavior. We reveal for the first time the influence of a hierarchically decomposed B2 + A2 structure in an AlCo0.5Cr0.5FeNi HEA on the formation of magnetic vortex states within individual A2 (disordered BCC) precipitates, which are distributed in an ordered B2 matrix that is weakly ferromagnetic. Non-magnetic or weakly ferromagnetic B2 precipitates in large magnetic domains of the A2 phase, and strongly magnetic Fe-Co-rich interphase A2 regions, are also observed. These results provide important insight into the origin of coercivity in this HEA, which can be attributed to a complex magnetization process that includes the successive reversal of magnetic vortices.

17.
Inflamm Res ; 71(4): 397-407, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35275225

RESUMEN

PURPOSE: Our study aimed to investigate the function of Cavin-1 and SOCS3 in macrophages/microglia M2 polarization and further explored the relevant mechanism. METHODS: Expression levels of Cavin-1 and SOCS3 in macrophages/microglia were measured by western blotting and RT-PCR, respectively. Then, Cavin-1 or SOCS3 was gene silenced by a siRNA approach, and gene silencing efficiency was determined by western blotting. Next, co-immunoprecipitation (Co-IP) was employed to further analyze the interaction between Cavin-1 and SOCS3. Finally, the activation of STAT6/PPAR-γ signaling was evaluated using western blotting, and the M2 macrophages/microglia polarization was validated by measuring the mRNA expression of M2 markers by RT-PCR. RESULTS: In the polarization process of macrophages/microglia to M2 phenotype, both Cavin-1 and SOCS3 increased synchronously at protein and mRNA level, reached the peak at the 6 h, and then decreased. After Cavin-1 or SOCS3 silencing, the expression of Cavin-1 and SOCS3 declined. These results suggested that Cavin-1 and SOCS3 were positively correlated in macrophages/microglia, and this conjecture was verified by Co-IP. Besides, Cavin-1 silencing not only suppressed the activation of STAT6/PPAR-γ pathway, but also suppressed the release of anti-inflammatory factors. Finally, we found that SOCS3 overexpression reversed the inhibitory effect of Cavin-1 silencing on the release of anti-inflammatory factors in M2 macrophages/microglia. CONCLUSIONS: Cavin-1 and SOCS3 are actively involved in the process of M2 macrophages/microglia polarization. As a SOCS3 interacting protein, Cavin-1 can promote M2 macrophages/microglia polarization via SOCS3.


Asunto(s)
Microglía , Receptores Activados del Proliferador del Peroxisoma , Antiinflamatorios/farmacología , Macrófagos , Microglía/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , ARN Mensajero/metabolismo
18.
ACS Appl Mater Interfaces ; 14(6): 8297-8310, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35130700

RESUMEN

Designing and fabricating high-performance microwave absorption materials with efficient electromagnetic absorption and corrosion resistance becomes a serious and urgent concern. Herein, novel corrosion-resistant graphene-based carbon-coated iron (Fe@C) magnetic composite foam is fabricated via self-assembly of iron phthalocyanine/Fe3O4 (FePc hybrid) on the graphene skeletons under solvothermal conditions and then annealing at high temperature. As a result, the rational construction of a hierarchical impedance gradient between graphene skeletons and Fe@C particles can facilitate the optimization in impedance matching and attenuation characteristic of the foam, realizing the efficient dissipation for incident electromagnetic waves. Additionally, the performance of electromagnetic absorption can be controllably regulated by optimizing annealing temperature and/or time. More importantly, the formation of a carbon-coated iron structure substantially improves the corrosion resistance of magnetic particles, endowing the composite foam with excellent stability and durability in microwave absorption performance.

19.
Graefes Arch Clin Exp Ophthalmol ; 260(4): 1205-1213, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34825956

RESUMEN

PURPOSE: To evaluate binocular visual function after unilateral and bilateral implantation of segmented refractive multifocal intraocular lenses (MIOLs). METHODS: This prospective comparative pilot study included patients who underwent SBL-3 (Lenstec; + 3.00 D) implantation at Peking University Third Hospital. Patients were divided into two groups (monocular or binocular surgery). Thirty-two patients with emmetropic presbyopic contralateral eyes and 49 patients with bilateral SBL-3 implantation within a week between eyes were included in the unilateral SBL-3 and bilateral groups, respectively. At 3-month follow-up, the main outcomes were binocular uncorrected distant, intermediate, and near visual acuity (UDVA, UIVA, and UNVA). Secondary outcomes included binocular best-corrected visual acuity at all distances, defocus curve, contrast sensitivity, photic phenomena, spectacle independence, patient satisfaction, and National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) score. The essential perceptual phenomena constituting binocular vision, simultaneous perception, fusion, and stereopsis were also evaluated. RESULTS: Both groups showed similar binocular UDVA and UIVA, but UNVA was significantly better in the bilateral group (0.07 ± 0.07 versus 0.12 ± 0.07, P = 0.008). Better binocular defocus curve at intermediate to near focal points, higher percentage of spectacle independence at near distance, and NEI-VFQ-25 near activity scores were observed in the bilateral group. No significant differences in contrast sensitivity, photic phenomena, overall satisfaction, other NEI-VFQ-25 subscales, fusional amplitude, and stereoacuity were found between groups. CONCLUSION: Unilateral implantation of segmented refractive MIOL provided desirable distant visual acuity and high patient satisfaction, but inferior intermediate and near visual outcomes compared with bilateral implantation.


Asunto(s)
Lentes Intraoculares , Lentes Intraoculares Multifocales , Facoemulsificación , Humanos , Implantación de Lentes Intraoculares , Satisfacción del Paciente , Proyectos Piloto , Estudios Prospectivos , Diseño de Prótesis , Seudofaquia , Visión Binocular
20.
Nano Lett ; 21(19): 8236-8243, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34597051

RESUMEN

Graphene oxide (GO) is receiving tremendous attention in membrane separation; however, its desalination performances remain suboptimal because of excessive swelling and tortuous transport pathways. Herein, we chemically joint GO nanosheets and phenolic nanomeshes together to form laminated membranes comprising through-plane nanopores and stabilized nanochannels. GO and phenolic/polyether nanosheets are mixed to form stacked structures and then treated in H2SO4 to remove polyether to produce nanomeshes and to chemically joint GO with phenolic nanomeshes. Thus-synthesized laminated membranes possess enhanced interlayer interactions and narrowed interlayer spacings down to 6.4 Å. They exhibit water permeance up to 165.6 L/(m2 h bar) and Na2SO4 rejection of 97%, outperforming most GO-based membranes reported so far. Moreover, the membranes are exceptionally stable in water because the chemically jointed laminates suppress the swelling of GO. This work reports hybrid laminated structures of GO and phenolic nanomeshes, which are highly desired in desalination and other applications.


Asunto(s)
Grafito , Nanoporos , Membranas Artificiales , Agua
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