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1.
Laterality ; : 1-13, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39442003

RESUMEN

This study aimed to compare the dominant and non-dominant eyes of healthy individuals in terms of CT and CVI values to assess the effect of ocular dominance on choroidal morphology. Three hundred eyes of 150 individuals were included in this study. All patients underwent routine ophthalmological examinations and hole-in-the-card tests to determine the dominant eye. EDI-OCT was used to obtain choroidal images. Choroidal thickness (CT) was measured at three points on the choroid including the subfoveal region (subfoveal choroidal thickness (SFCT)), 1500 µm nasal (NCT) and temporal (TCT) to the fovea. Choroidal vascularity index (CVI), total choroidal area (TCA), luminal area (LA), and stromal area (SA) were measured at fovea-centered choroidal area by image binarization via Image J software. While 93(%62) participants were right-eyed, 57(%38) participants were left-eyed. We could not detect any difference in SFCT, NCT, TCT, TCA, LA, SA, and CVI measurements between the dominant and the non-dominant eyes. (p > 0.05 for all). We could not detect any effect of ocular dominance on choroidal structures. These results also support the use of randomized ocular data regardless of which eye is dominant when investigating CVI and CT in scientific research.

2.
Eye Contact Lens ; 49(11): 508-510, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37625153

RESUMEN

PURPOSE: To investigate the effects of coronavirus disease 2019 (COVID-19) infection on the corneal endothelium in children. METHODS: This retrospective study included 46 pediatric patients with COVID-19 infection and 38 healthy controls. Specular microscopy measurements were analyzed, and measurements were obtained from images showing at least 100 cells with clear borders. Mean endothelial cell density, mean hexagonal cell percentage (HEX), mean coefficient of variation (CV), central corneal thickness, and mean cell area were evaluated. RESULTS: Specular microscopy data showed that the CV values were 2.442±6.517 in the healthy control group (HCG) and 2.659±5.119 in the COVID-19-affected group (CAG) ( P =0.003). The hexagonality of the HCG and CAG were 6.916±8.271 and 6.683±5.885, respectively ( P =0.011). CONCLUSION: A decrease in the HEX and an increase in the CV were observed in the corneal specular microscopic examination of children with COVID-19 infection. These results are important in demonstrating the corneal effects of COVID-19 infection in children.


Asunto(s)
COVID-19 , Endotelio Corneal , Humanos , Niño , Estudios Retrospectivos , Estudios Prospectivos , Córnea , Recuento de Células
3.
Eye Contact Lens ; 49(7): 296-300, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37171496

RESUMEN

PURPOSE: To compare the effects of cooled and room temperature irrigation on the preoperative and early postoperative corneal endothelial parameter values in posterior vitrectomy. MATERIALS AND METHODS: In this prospective, randomized, comparative study, 68 patients underwent a standard 3-port, 23-G posterior vitrectomy operation by a single surgeon. Cooled irrigation solution was applied to 36 patients during surgery (group 1), and room temperature irrigation solution was applied to 32 patients (group 2). The patients were also divided into four groups according to their history of noncomplicated cataract surgery (phakic or pseudophakic) and the types of tamponade used (silicone or gas). The central corneal thickness (CCT), endothelial cell density (ECD), mean cell area (MCA), hexagonal cell percent, and coefficient of variation of cell area (CV) parameter values of the groups at preoperative and postoperative 1 month were compared. RESULTS: There were no statistically significant differences between the preoperative and postoperative corneal parameter values in groups 1 and 2 ( P >0.05). However, it was remarkable that the percentage of preoperative-postoperative change in all the corneal parameter values was higher in group 2. When the results of the subgroup analyses of the patients who were pseudophakic and used gas tamponade (Group D) in group 2 were examined, it was determined that the negative effects were significantly higher in the postoperative values for the ECD, MCA, CV, and CCT parameters compared with the preoperative values ( P <0.05). CONCLUSION: In patients with pseudophakia and gas tamponade, cooled irrigation was found to be more advantageous for corneal parameters.


Asunto(s)
Endotelio Corneal , Vitrectomía , Humanos , Temperatura , Estudios Prospectivos , Córnea/cirugía , Recuento de Células
4.
Int Ophthalmol ; 43(7): 2301-2306, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36595126

RESUMEN

PURPOSE: To evaluate the ocular findings and the relationship between these findings and the disease severity of patients with Fabry disease (FD) in South-East Anatolia. METHODS: We enrolled the 24 eyes of 24 patients with FD and the disease severity scores were obtained with FD severity scoring system (DS3). The relationship between the presence of any ocular findings and DS3 scores was evaluated. RESULTS: The mean age of the patients was 35.2 ± 8.6 years. The mean DS3 score and α-galactosidase A enzyme activity of the patients was 7.04 ± 3.71 and 1.93 ± 0.84 µmol/l/h, respectively. Of the 24 patients, 20 (83.3%) had cornea verticillate (CV), 18 (75%) had tortuous conjunctival vessels, 15 (62.5%) had tortuous retinal vessels and 3 (12.5%) had lens opacities. The ocular vascular abnormalities were associated with disease severity (p < 0.05); however, the presence of CV did not affect the DS3 scores (p > 0.05). CONCLUSIONS: According to our study, the patients with ocular vascular abnormalities associated with FD had more severe disease than those who did not have an abnormality. CV was the most common ocular finding in FD, but it has no association with disease severity.


Asunto(s)
Catarata , Enfermedad de Fabry , Humanos , Adulto , Enfermedad de Fabry/complicaciones , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/epidemiología , Turquía/epidemiología , alfa-Galactosidasa , Catarata/complicaciones , Gravedad del Paciente
5.
Retina ; 42(10): 1931-1938, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36129266

RESUMEN

PURPOSE: To investigate the changes in the microvascular structure of the retina and optic disk by comparing the optical coherence tomography angiography findings in preeclamptic patients with those in healthy pregnant women and healthy nonpregnant women and also to evaluate the preeclamptic patients after delivery by showing whether the changes are permanent or not. METHODS: Fifty preeclamptic, 50 healthy pregnant, and 50 healthy nonpregnant women enrolled in three groups (preeclamptic pregnant women group, healthy pregnant women group, and nonpregnant women group; respectively). Patients in the preeclamptic pregnant women group were evaluated at three different time points including up to 3 hours before delivery (Group 1), 2, or 3 days after delivery (Group 2), and 6 weeks after delivery (Group 3), and compared with each other. All patients underwent a comprehensive ophthalmologic examination including optical coherence tomography angiography. RESULTS: Choriocapillaris blood flow area, deep foveal density, deep temporal density, deep nasal density, and radial peripapillary capillary inside disk density values were significantly lower in the preeclamptic pregnant women group than in the healthy pregnant women group. Deep foveal density and deep nasal density values were significantly higher in Group 3 than in Group 1 and 2, and deep temporal density was significantly higher in Group 3 than in Group 1. CONCLUSION: Optical coherence tomography angiography diagnosed decreased deep retinal capillary density values in the macula of patients with preeclampsia, but these results improved after delivery.


Asunto(s)
Mácula Lútea , Disco Óptico , Preeclampsia , Femenino , Angiografía con Fluoresceína/métodos , Humanos , Mácula Lútea/irrigación sanguínea , Disco Óptico/irrigación sanguínea , Preeclampsia/diagnóstico , Embarazo , Vasos Retinianos/fisiología , Tomografía de Coherencia Óptica/métodos
6.
Nano Lett ; 19(7): 4297-4305, 2019 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-31185570

RESUMEN

We proposed and showed strongly orientation-controlled Förster resonance energy transfer (FRET) to highly anisotropic CdSe nanoplatelets (NPLs). For this purpose, we developed a liquid-air interface self-assembly technique specific to depositing a complete monolayer of NPLs only in a single desired orientation, either fully stacked (edge-up) or fully nonstacked (face-down), with near-unity surface coverage and across large areas over 20 cm2. These NPL monolayers were employed as acceptors in an energy transfer working model system to pair with CdZnS/ZnS core/shell quantum dots (QDs) as donors. We found the resulting energy transfer from the QDs to be significantly accelerated (by up to 50%) to the edge-up NPL monolayer compared to the face-down one. We revealed that this acceleration of FRET is accounted for by the enhancement of the dipole-dipole interaction factor between a QD-NPL pair (increased from 1/3 to 5/6) as well as the closer packing of NPLs with stacking. Also systematically studying the distance-dependence of FRET between QDs and NPL monolayers via varying their separation (d) with a dielectric spacer, we found out that the FRET rate scales with d-4 regardless of the specific NPL orientation. Our FRET model, which is based on the original Förster theory, computes the FRET efficiencies in excellent agreement with our experimental results and explains well the enhancement of FRET to NPLs with stacking. These findings indicate that the geometrical orientation of NPLs and thereby their dipole interaction strength can be exploited as an additional degree of freedom to control and tune the energy transfer rate.

7.
Small ; 15(8): e1804854, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30701687

RESUMEN

Colloidal semiconductor nanoplatelets (NPLs) offer important benefits in nanocrystal optoelectronics with their unique excitonic properties. For NPLs, colloidal atomic layer deposition (c-ALD) provides the ability to produce their core/shell heterostructures. However, as c-ALD takes place at room temperature, this technique allows for only limited stability and low quantum yield. Here, highly stable, near-unity efficiency CdSe/ZnS NPLs are shown using hot-injection (HI) shell growth performed at 573 K, enabling routinely reproducible quantum yields up to 98%. These CdSe/ZnS HI-shell hetero-NPLs fully recover their initial photoluminescence (PL) intensity in solution after a heating cycle from 300 to 525 K under inert gas atmosphere, and their solid films exhibit 100% recovery of their initial PL intensity after a heating cycle up to 400 K under ambient atmosphere, by far outperforming the control group of c-ALD shell-coated CdSe/ZnS NPLs, which can sustain only 20% of their PL. In optical gain measurements, these core/HI-shell NPLs exhibit ultralow gain thresholds reaching ≈7 µJ cm-2 . Despite being annealed at 500 K, these ZnS-HI-shell NPLs possess low gain thresholds as small as 25 µJ cm-2 . These findings indicate that the proposed 573 K HI-shell-grown CdSe/ZnS NPLs hold great promise for extraordinarily high performance in nanocrystal optoelectronics.

8.
J Neural Transm (Vienna) ; 124(1): 25-32, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-26645377

RESUMEN

No field in science and medicine today remains untouched by Big Data, and psychiatry is no exception. Proteomics is a Big Data technology and a next generation biomarker, supporting novel system diagnostics and therapeutics in psychiatry. Proteomics technology is, in fact, much older than genomics and dates to the 1970s, well before the launch of the international Human Genome Project. While the genome has long been framed as the master or "elite" executive molecule in cell biology, the proteome by contrast is humble. Yet the proteome is critical for life-it ensures the daily functioning of cells and whole organisms. In short, proteins are the blue-collar workers of biology, the down-to-earth molecules that we cannot live without. Since 2010, proteomics has found renewed meaning and international attention with the launch of the Human Proteome Project and the growing interest in Big Data technologies such as proteomics. This article presents an interdisciplinary technology foresight analysis and conceptualizes the terms "environtome" and "social proteome". We define "environtome" as the entire complement of elements external to the human host, from microbiome, ambient temperature and weather conditions to government innovation policies, stock market dynamics, human values, political power and social norms that collectively shape the human host spatially and temporally. The "social proteome" is the subset of the environtome that influences the transition of proteomics technology to innovative applications in society. The social proteome encompasses, for example, new reimbursement schemes and business innovation models for proteomics diagnostics that depart from the "once-a-life-time" genotypic tests and the anticipated hype attendant to context and time sensitive proteomics tests. Building on the "nesting principle" for governance of complex systems as discussed by Elinor Ostrom, we propose here a 3-tiered organizational architecture for Big Data science such as proteomics. The proposed nested governance structure is comprised of (a) scientists, (b) ethicists, and (c) scholars in the nascent field of "ethics-of-ethics", and aims to cultivate a robust social proteome for personalized medicine. Ostrom often noted that such nested governance designs offer assurance that political power embedded in innovation processes is distributed evenly and is not concentrated disproportionately in a single overbearing stakeholder or person. We agree with this assessment and conclude by underscoring the synergistic value of social and biological proteomes to realize the full potentials of proteomics science for personalized medicine in psychiatry in the present era of Big Data.


Asunto(s)
Medicina de Precisión , Proteoma , Humanos , Trastornos Mentales/diagnóstico , Trastornos Mentales/metabolismo , Trastornos Mentales/terapia , Proteómica/instrumentación , Proteómica/métodos , Psiquiatría/instrumentación , Psiquiatría/métodos
9.
Int Ophthalmol ; 37(4): 1057-1063, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27614461

RESUMEN

PURPOSE: We report the outcomes of three consecutive patients with optic disc pit-associated maculopathy who were treated with 25-gauge pars plana vitrectomy, internal limiting membrane (ILM) peeling, fluid-air exchange, barrage endolaser, and sulfur hexafluoride (SF6) gas tamponade. CASE REPORT: Patients with optic disc pit-associated maculopathy were treated with 25-gauge pars plana vitrectomy followed by ILM peeling, fluid-air exchange, barrage endolaser, and gas tamponade with 20 % SF6. All patients were asked to maintain a facedown position for 3 days postoperatively. This technique resulted in complete retinal reattachment after 25-gauge vitrectomy, ILM peeling, fluid-air exchange, barrage endolaser, and 20 % SF6 gas injection. The best-corrected visual acuity (BCVA) improved in all three patients and successful anatomical results were achieved. There wasn't any macular detachment in all cases at 20th week follow-up. CONCLUSIONS: Our outcomes suggest that 25-gauge vitrectomy with ILM peeling, fluid-air exchange, barrage endolaser, and SF6 gas tamponade appears to be an effective treatment option for optic disc pit-associated maculopathy.


Asunto(s)
Disco Óptico/anomalías , Enfermedades del Nervio Óptico/cirugía , Enfermedades de la Retina/cirugía , Cirugía Vitreorretiniana/métodos , Adolescente , Endotaponamiento , Femenino , Humanos , Masculino , Enfermedades del Nervio Óptico/complicaciones , Enfermedades del Nervio Óptico/congénito , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/etiología , Tomografía de Coherencia Óptica , Adulto Joven
10.
Int Ophthalmol ; 37(2): 349-356, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27334604

RESUMEN

The objective of this study is to compare pain and discomfort scores of patients during 23-G vitreoretinal surgery under topical and retrobulbar anesthesia without using sedation. A total of 157 patients with various vitreoretinal disorders were included in this study. Patients were randomly divided into two groups: topical (group 1, n = 76) and retrobulbar anesthesia (group 2, n = 81). Patients underwent 23-G vitreoretinal surgery without using sedation. All patients rated the level of experienced pain during the surgical procedure using a visual analogue pain scale. Pain and discomfort scores while performing anesthesia were significantly higher in group 2 than group 1 (p < 0.001). Patients in group 1 experienced more pain than group 2 during trocar insertion, endolaser photocoagulation, and scleral indentation steps of surgery (for all; p < 0.001). There was no significant difference in overall pain and discomfort scores and surgeon comfort scores between groups (p = 0.163, p = 0.097; respectively). None of the patients required additional anesthesia or sedation during or after the procedure. Topical anesthesia without using sedation is a safe and effective, alternative method for 23-G vitreoretinal surgeries in selected patients with various vitreoretinal pathologies.


Asunto(s)
Anestesia Local/métodos , Lidocaína/administración & dosificación , Dolor Postoperatorio/prevención & control , Satisfacción del Paciente , Cirugía Vitreorretiniana/métodos , Adulto , Anciano , Anciano de 80 o más Años , Anestésicos Locales/administración & dosificación , Femenino , Humanos , Inyecciones , Periodo Intraoperatorio , Masculino , Persona de Mediana Edad , Órbita , Dimensión del Dolor , Dolor Postoperatorio/diagnóstico , Adulto Joven
11.
Indian J Ophthalmol ; 72(Suppl 2): S293-S297, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271426

RESUMEN

PURPOSE: To evaluate the effect of age-related macular degeneration (AMD) on vision-related quality of life (VRQOL) and depression levels. METHODS: This cross-sectional study included 143 patients who are being followed up with a diagnosis of AMD. The Turkish versions of the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) and Geriatric Depression Scale-15 (GDS-15) were directed to the patients. The questionnaire results were analyzed based on the severity, treatment procedures for AMD, and sociodemographic characteristics of patients. RESULTS: The subscale scores obtained from the NEI VFQ-25 ranged from 47.54 for "near activities" to 84.02 for "color vision." Of the patients, 59.4% (85/143) were compatible with depression according to the GDS-15 questionnaire. There was no significant difference in the NEI VFQ-25 subscale scores between the gender groups (P > 0.05), whereas females were statistically significantly more depressive than males (P < 0.05). There were no significant differences between the injection (anti-vascular endothelial growth factors [anti-VEGF]) group and the non-injection group in terms of subscales of the NEI VFQ-25 questionnaire (P > 0.05). The depression ratio in the non-injected group was statistically significantly higher (P < 0.05). CONCLUSION: According to the present study, the association between depression and AMD is a fact that should be highlighted. Patients with depression had lower scores on the quality of life (QOL) test. Previous intravitreal injection did not affect NEI VFQ-25 scores. Female patients with AMD had higher rates of depression and lower visual acuity levels.


Asunto(s)
Degeneración Macular , Calidad de Vida , Masculino , Humanos , Femenino , Anciano , Estudios Transversales , Depresión/diagnóstico , Depresión/epidemiología , Depresión/etiología , Degeneración Macular/complicaciones , Degeneración Macular/diagnóstico , Degeneración Macular/epidemiología , Agudeza Visual , Encuestas y Cuestionarios
12.
Eur J Ophthalmol ; 34(1): 175-180, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37424261

RESUMEN

PURPOSE: To investigate the relationship between serum iron status indicators (ferritin) levels and POAG. METHODS: The files of all glaucoma patients who applied to the ophthalmology clinic between January 2018 and January 2022 were reviewed retrospectively. Laboratory data from fasting blood tests, internal medicine outpatient clinic reports, and extensive ophthalmologic examination data, including fundus photographs showing the optic disc, were collected from the files. A control group was formed from individuals with adequate general and eye health, age- and gender-matched individuals who had undergone examination in the ophthalmology clinic within the same date range. Serum iron status indicators and some laboratory data of POAG patients and healthy controls were compared. RESULT: Of our participants, consisting of 65 patients with POAG and 72 healthy controls, 84 (61.32%) were female and 53 (38.68%) were male. It was observed that serum ferritin level was significantly higher in POAG patients compared to healthy controls, and the total iron binding capacity was significantly lower (respectively (p = 0.022), (p = 0.002). In logistic regression analysis, it was found that the risk of POAG increased in cases with high serum ferritin levels (OR = 0.982; p = 0.012). In addition, the risk of POAG was found to increase in cases where MCV was lower (OR = 1.121; p = 0.039). CONCLUSION: This study shows that higher serum ferritin levels are associated with a higher risk of POAG.


Asunto(s)
Glaucoma de Ángulo Abierto , Disco Óptico , Humanos , Masculino , Femenino , Glaucoma de Ángulo Abierto/diagnóstico , Estudios Retrospectivos , Ferritinas , Hierro , Presión Intraocular
13.
Acta Neurol Belg ; 124(3): 987-993, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38546932

RESUMEN

We aimed to investigate the diagnostic value of Optical coherence tomography (OCT) in Alzheimer's disease (AD) and to assess the correlation between OCT and fluorodeoxyglucose (FDG)-positron emission tomography (PET) which shows high diagnostic agreement with findings from postmortem histopathology-the gold standard method. Patients who were diagnosed with AD-related dementia were selected for the study. Patients with a mini mental test (MMT) score between 18 and 23 were included in the study (n = 31). Volunteers with MMT ≥ 28 and no cognitive impairment were included in the study as the control group (n = 31). OCT imaging was performed in the patient and control groups after detailed ophthalmological examinations including visual acuity and intraocular pressure measurements. Brain glucose metabolism measurement was performed using 18 F-FDG PET/computed tomography. When adjusted for age and sex, mean retinal nerve fiber layer thickness (RNFL) thickness showed a significant difference between groups and the RNFL thickness in the superior temporal and superior nasal quadrants in AD-related mild dementia group showed a significant difference (p < 0.05). Furthermore, only the RNFL thickness in the inferior nasal quadrant of the right eye showed a significant difference between the groups (p = 0.016). It is thought that OCT is a promising imaging method in the elderly population due to its low-cost, non-invasive and easily applicability, and therefore, it may contribute in the future as a tool in the periodic follow-up of patients diagnosed with AD.


Asunto(s)
Enfermedad de Alzheimer , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones , Retina , Tomografía de Coherencia Óptica , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Femenino , Masculino , Anciano , Tomografía de Coherencia Óptica/métodos , Retina/diagnóstico por imagen , Retina/patología , Retina/metabolismo , Tomografía de Emisión de Positrones/métodos , Persona de Mediana Edad , Anciano de 80 o más Años , Radiofármacos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos
14.
Nanoscale Horiz ; 9(10): 1756-1765, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39045702

RESUMEN

Colloidal quantum dots (QDs) offer high color purity essential to high-quality liquid crystal displays (LCDs), which enables unprecedented levels of color enrichment in LCD-TVs today. However, for LCDs requiring polarized backplane illumination in operation, highly polarized light generation using inherently isotropic QDs remains a fundamental challenge. Here, we show strongly polarized color conversion of isotropic QDs coupled to Fano resonances of v-grooved surfaces compatible with surface-normal LED illumination for next-generation QD-TVs. This architecture overcomes the critically oblique excitation of surface plasmon coupled emission by using v-shapes imprinted on the backlight unit (BLU). With isotropic QDs coated on the proposed v-BLU surface, we experimentally measured a far-field polarization contrast ratio of ∼10. Full electromagnetic solution shows Fano line-shape transmission in transverse magnetic polarization allowing for high transmission as an indication for forward-scattering configuration. Of these QDs coupled to the surface plasmon-polariton modes, we observed strong modifications in their emission kinetics revealed by time-resolved photoluminescence spectroscopy and via dipole orientations identified by back focal plane imaging. This collection of findings indicates conclusively that these isotropic QDs are forced to radiate in a linearly polarized state from the patterned planar surface under surface-normal excitation. For next-generation QD-TVs, the proposed polarized color-converting isotropic QDs on such v-BLUs can be deployed in bendable electronic displays.

15.
Opt Express ; 21(20): 23097-106, 2013 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-24104225

RESUMEN

Conventional two-dimensional (2D) plasmonic arrays provide electric field intensity enhancement in the plane, typically with a surface coverage around 50% in the plan-view. Here, we show nanoplasmonic three-dimensional (3D) surfaces with 100% surface coverage enabling strong surface-normal field enhancement. Experimental measurements are found to agree well with the full electromagnetic solution. Along with the surface-normal localization when using the plasmonic 3D-surface, observed maximum field enhancement is 7.2-fold stronger in the 3D-surface than that of the 2D counterpart structure. 3D-plasmonic nonplanar surfaces provide the ability to generate volumetric field enhancement, possibly useful for enhanced plasmonic coupling and interactions.

16.
Nanotechnology ; 24(15): 155201, 2013 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-23519189

RESUMEN

We report plasmonically coupled light-sensitive skins of nanocrystal monolayers that exhibit sensitivity enhancement and spectral range extension with plasmonic nanostructures embedded in their photosensitive nanocrystal platforms. The deposited plasmonic silver nanoparticles of the device increase the optical absorption of a CdTe nanocrystal monolayer incorporated in the device. Controlled separation of these metallic nanoparticles in the vicinity of semiconductor nanocrystals enables optimization of the photovoltage buildup in the proposed nanostructure platform. The enhancement factor was found to depend on the excitation wavelength. We observed broadband sensitivity improvement (across 400-650 nm), with a 2.6-fold enhancement factor around the localized plasmon resonance peak. The simulation results were found to agree well with the experimental data. Such plasmonically enhanced nanocrystal skins hold great promise for large-area UV/visible sensing applications.

17.
Adv Mater ; 35(9): e2206613, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36528387

RESUMEN

Laser diodes based on solution-processable materials can benefit numerous technologies including integrated electronics and photonics, telecommunications, and medical diagnostics. An attractive system for implementing these devices is colloidal semiconductor quantum dots (QDs). The progress towards a QD laser diode has been hampered by rapid nonradiative Auger decay of optical-gain-active multicarrier states, fast device degradation at high current densities required for laser action, and unfavorable competition between optical gain and optical losses in a multicomponent device stack. Here we resolve some of these challenges and demonstrate optically excited lasing from fully functional high-current density electroluminescent (EL) devices with an integrated optical resonator. This advance has become possible due to excellent optical gain properties of continuously graded QDs and a refined device architecture, which allows for highly efficient light amplification in a thin, EL-active QD layer.

18.
Turk J Ophthalmol ; 53(6): 343-348, 2023 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-38014881

RESUMEN

Objectives: To determine the roles of small GTP-binding proteins Rac1, Rac2, and Rac3 expression in pterygial tissue and to compare these expressions with normal conjunctival tissue. Materials and Methods: Seventy-eight patients with primary pterygium were enrolled. Healthy conjunctival graft specimens obtained during pterygium surgery were used as control tissue. The real-time polymerase chain reaction method on the BioMark HD dynamic array system was utilized in genomic mRNA for the gene expression analysis. Protein expressions were analyzed using western blot and immunohistochemical methods. Results: RAC1, RAC2, and RAC3 gene expressions in pterygial tissues were not markedly elevated when compared to the control specimens (p>0.05). As a very low level of RAC1 gene expression was observed, further protein expression analysis was performed for the Rac2 and Rac3 proteins. Western blot and immunohistochemical analysis of Rac2 and Rac3 protein expression revealed no significant differences between pterygial and healthy tissues (p>0.05). Conclusion: This is the first study to identify the contribution of Rac proteins in pterygium. Our results indicate that the small GTP-binding protein Rac may not be involved in pterygium pathogenesis.


Asunto(s)
Pterigion , Humanos , Pterigion/cirugía , Pterigion/genética , Pterigion/metabolismo , Conjuntiva/metabolismo , Proteínas de Unión al GTP rac/genética , Proteínas de Unión al GTP rac/metabolismo , Western Blotting
19.
Photodiagnosis Photodyn Ther ; 42: 103549, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37028691

RESUMEN

PURPOSE: To evaluate the changes in the retinal and optic disc (OD) microcirculation in patients with Wilson's disease (WD) using optical coherence tomography angiography (OCTA). MATERIALS AND METHODS: This cross-sectional comparative study included 35 eyes of 35 WD patients (study group) and 36 eyes of 36 healthy participants (control group). The patients with WD were divided into subgroups based on the presence of Kayser-Fleischer rings. All the participants underwent a comprehensive ophthalmological examination, including OCTA. RESULTS: The inferior perifoveal deep capillary plexus vessel density (DCP-VD), inferior radial peripapillary capillary vessel density (RPC-VD), and inferior peripapillary retinal nerve fiber layer (PPRNFL) thickness were significantly lower in the WD group than in the healthy participants (p=0.041, p=0.043, and p=0.045, respectively). In addition, in the subgroup analysis, the superior RPC-VD and inferior PPRNFL were significantly lower in the subgroup with Kayser-Fleischer rings (p=0.013 and p=0.041, respectively). CONCLUSION: We showed there to be changes in certain OCTA parameters in WD patients when compared with healthy controls. Thus, we hypothesized that OCTA could detect any retinal microvascular changes in WD patients without clinical evidence of retinal or OD involvement.


Asunto(s)
Degeneración Hepatolenticular , Disco Óptico , Fotoquimioterapia , Humanos , Disco Óptico/diagnóstico por imagen , Disco Óptico/irrigación sanguínea , Angiografía con Fluoresceína/métodos , Vasos Retinianos/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Estudios Transversales , Degeneración Hepatolenticular/diagnóstico por imagen , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Coroides , Cobre
20.
Eur J Ophthalmol ; 33(1): 398-407, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35924358

RESUMEN

PURPOSE: To provide consensus on the clinical use of intravitreal dexamethasone (DEX) implant for the treatment of diabetic macular edema (DME) in Turkey. METHODS: A panel of 22 retina experts prepared 77 statements of recommendation, and 80 retinal specialists practicing in Turkey were chosen to vote either in support or against each one. A Delphi-based method was used through which the ophthalmologists were able to view all of the results anonymously after two rounds and modify their subsequent answers. The survey was conducted via a mini website, and statements without consensus were resent to the specialists with the latest vote results a week later. RESULTS: A total of 72 ophthalmologists answered the first and second round questions. After the first stage, consensus was achieved on 55 of the statements, leaving 22 without agreement. After the second stage, consensus was reached on 11 of the remaining statements. Strong consensus was achieved on statements regarding the etiopathogenesis of DME and the first-line indications and safety of the DEX implant procedure. The panel recommended the use of DEX implant for patients with an arterial thromboembolic event in the last three months and also agreed that pro re nata DEX implant treatment not only provides better outcomes for DME patients but also reduces the treatment burden for those who could not receive an adequate number of anti-vascular endothelial growth factor (VEGF) injections. CONCLUSION: This study provides clinical consensus and recommendations about the use of DEX implant in the clinical practice of DME management in Turkey.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Edema Macular/etiología , Dexametasona , Inhibidores de la Angiogénesis/uso terapéutico , Técnica Delphi , Turquía , Factor A de Crecimiento Endotelial Vascular , Implantes de Medicamentos/uso terapéutico , Inyecciones Intravítreas , Glucocorticoides , Resultado del Tratamiento , Diabetes Mellitus/tratamiento farmacológico
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