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1.
Korean J Ophthalmol ; 37(6): 453-461, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37899289

RESUMO

PURPOSE: This study aimed to investigate changes in cytokine levels after intravitreal bevacizumab injection in patients with chronic central serous chorioretinopathy (CSC). METHODS: In a prospective interventional trial, 12 eyes from 12 patients with chronic CSC and six eyes from six patients who underwent cataract surgery were included as controls. Patients diagnosed as with CSC received a single intravitreal injection of bevacizumab (1.25 mg/0.05 mL). Aqueous humor samples were collected from the patients and controls. Best-corrected visual acuity and foveal thickness were evaluated, and aqueous samples were obtained before and 4 weeks after injection. The aqueous concentrations of interleukin (IL)-6, IL-8, interferon-induced protein (IP)-10, monocyte chemotactic protein (MCP)-1, platelet-derived growth factor (PDGF)-AA, and vascular endothelial growth factor (VEGF) were measured using a multiplex bead assay. RESULTS: After injection, the foveal thickness decreased significantly from 328.08 µm (range, 210-477 µm) to 283.91 µm (range, 168-356 µm; p = 0.048), but the best-corrected visual acuity was not significantly different (p = 0.066). The aqueous levels of IL-8 increased significantly from 3.3 pg/mL (range, 1.5-8.3 pg/mL) to 4.7 pg/mL (range, 2.2-11.6 pg/mL) at 4 weeks after the injection (p = 0.046). The aqueous levels of VEGF decreased significantly from 31.4 pg/mL (range, 17.0-53.3 pg/mL) to 15.2 pg/mL (range, 7.7-21.5 pg/mL; p < 0.01). No significant changes in levels of IL-6 (p = 0.455), IP-10 (p = 0.055), MCP-1 (p = 0.076), and PDGF-AA (p = 0.339) were noted 4 weeks after injection. CONCLUSIONS: In this study we found intravitreal bevacizumab injection decreased VEGF and increased IL-8 in the eyes of patients with chronic CSC. This study suggests the possibility that the pathogenesis of CSC may be related to abnormal circulation of the choroidal blood vessels through VEGF and IL-8 cytokine level changes.


Assuntos
Coriorretinopatia Serosa Central , Citocinas , Humanos , Bevacizumab/uso terapêutico , Citocinas/metabolismo , Citocinas/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Injeções Intravítreas , Interleucina-8/metabolismo , Interleucina-8/uso terapêutico , Coriorretinopatia Serosa Central/diagnóstico , Coriorretinopatia Serosa Central/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Estudos Prospectivos , Anticorpos Monoclonais Humanizados/metabolismo , Anticorpos Monoclonais Humanizados/uso terapêutico , Interleucina-6 , Humor Aquoso
2.
BMC Ophthalmol ; 23(1): 236, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237351

RESUMO

BACKGROUND: To compare the intraoperative challenges, complications, and operation time of illuminated chopper-assisted cataract surgery between cataract surgery only and phacovitrectomy in eyes with diabetic retinopathy. METHODS: One university hospital, retrospective case series. Two hundred ninety-five eyes of 295 consecutive patients with diabetic retinopathy who underwent cataract surgery only or phacovitrectomy were retrospectively reviewed. Intraoperative challenges and complications of cataract surgery were thoroughly analyzed by 3D viewing of digitally recorded videos. The pupil diameter, operation time, and improved efficacy (100/operation time × pupil diameter) were compared between the cataract surgery only and phacovitrectomy groups. RESULTS: Of the 295 eyes, 211 underwent cataract surgery only, and 84 underwent phacovitrectomy. Intraoperative challenges such as small pupil, miosis, or poor red reflex occurred more frequently (46 [21.8%] vs. 28 [33.3%], p = 0.029); pupil diameter was smaller (7.34 ± 0.94 vs. 6.89 ± 0.88 mm, p < 0.001) in the phacovitrectomy group than in the cataract surgery only group; however, rates of posterior capsule rupture and operation time were not different between the two groups (0 [0%] vs. 1 [1.2%], p = 0.285; 16.54 ± 2.65 vs. 16.31 ± 4.30 min, p = 0.434). Improved efficacy was higher in the phacovitrectomy group (0.85 ± 0.18 vs. 0.97 ± 0.28, p = 0.002). CONCLUSIONS: The use of an illuminated chopper is a potential solution for diabetic cataract surgery, particularly in phacovitrectomy, by decreasing the use of supplemental devices, operation time, and posterior capsule rupture. TRIAL REGISTRATION: Retrospectively registered.


Assuntos
Extração de Catarata , Catarata , Diabetes Mellitus , Retinopatia Diabética , Facoemulsificação , Humanos , Retinopatia Diabética/complicações , Retinopatia Diabética/cirurgia , Estudos Retrospectivos , Complicações Pós-Operatórias/cirurgia , Catarata/complicações , Complicações Intraoperatórias/cirurgia
3.
Retina ; 43(12): 2173-2176, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913622

RESUMO

PURPOSE: To introduce a new surgical technique with a beveled vitrectomy probe for the removal of peripheral vitreous cortex remnants (VCR) in primary rhegmatogenous retinal detachment (RRD). METHODS: This study was a retrospective case series. From September 2019 to June 2022, 54 patients with complete or partial posterior vitreous detachment who underwent vitrectomy for primary RRD by a single surgeon were enrolled. RESULTS: After staining the vitreous with triamcinolone acetonide, the presence of VCR was assessed in detail. If VCR were present, the macular VCR were removed using surgical forceps, and then, a free flap of peripheral VCR was used as a handle for removing peripheral VCR using the beveled vitrectomy probe. Of the total patients, the presence of VCR was confirmed in 16 patients (29.6%). There were no intraoperative or postoperative complications, except for retinal redetachment caused by proliferative vitreoretinopathy, that occurred in only one eye (1.9%). CONCLUSION: Using a beveled vitrectomy probe was a practical solution for removing VCR during RRD vitrectomy because additional instruments were not needed and risk of iatrogenic retinal damage was low.


Assuntos
Descolamento Retiniano , Doenças Retinianas , Humanos , Descolamento Retiniano/cirurgia , Descolamento Retiniano/etiologia , Vitrectomia/métodos , Estudos Retrospectivos , Doenças Retinianas/cirurgia , Triancinolona Acetonida
4.
J Ophthalmol ; 2019: 1594152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30755800

RESUMO

PURPOSE: To evaluate intraoperative complications and utilization of adjunctive devices between microscope and intracameral illuminations during cataract surgery in the elderly over 75 years. DESIGN: A retrospective, consecutive, interventional case series Participants. Two hundred eighty-six eyes of 184 patients older than 75 years who underwent cataract surgery using microscope and intracameral illuminations. METHODS: A chart review was performed on an advanced cataract surgery group of 141 consecutive cases in which the intracameral illumination was used and on a standard cataract surgery group of 145 consecutive cases in which the intracameral illumination was not used. MAIN OUTCOME MEASURES: Intraoperative complications (posterior capsule rupture, radial tear of the anterior capsule, dropped nucleus, or sulcus-implanted/sclera-fixated IOL) and utilization of adjunctive devices (pupil expansion device or anterior capsule staining). RESULTS: The frequency of use of the pupil expansion device was lower in the advanced cataract surgery group than that in the standard cataract surgery group (0.7% vs 6.9%; p=0.007). Furthermore, the rates of a posterior capsule rupture and at least one intraoperative complication were lower in the advanced cataract surgery group than those in the standard cataract surgery group (0.7% vs 4.8%; p=0.067) (0.7% vs 7.6%; p=0.004). CONCLUSIONS: In the current cohort of patients over 75 years, the rate of intraoperative complications was lower when using the intracameral illumination than that when using the conventional method. Cataract surgery using intracameral illumination would be good option for elderly people.

5.
Curr Eye Res ; 44(3): 334-340, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30311807

RESUMO

PURPOSE: To demonstrate the advantages and efficacy of an air-perfused membrane dissection to control intraoperative bleeding in 23-gauge sutureless vitrectomy for proliferative diabetic retinopathy with severe fibrovascular membranes. Meterials and Methods: A prospective, consecutive, interventional case series of 15 eyes that underwent air-perfused diabetic vitrectomy (air vitrectomy group) for removal of the membranes was compared with a retrospective, membrane-matched case series of 10 eyes that underwent conventional diabetic vitrectomy (conventional vitrectomy group). The main outcome measures were real vitrectomy time, intraoperative and postoperative complications, and anatomic and functional successes at the final examination. RESULTS: The incidence of intraoperative retinal tears was 30% (3/10 eyes) in the conventional vitrectomy group and 20% (3/15 eyes) in the air vitrectomy group (p > 0.05). The postoperative complications such as vitreous hemorrhage or tractional retinal detachment were not common in both groups during the 6-month follow-up (p > 0.05). In addition, the final anatomic and functional success rates did not differ significantly between the groups (p > 0.05). However, the vitrectomy time was significantly shorter in the air vitrectomy group (67.0 ± 21.8 min) than in the conventional group (84.6 ± 21.1 min) (p = 0.04). CONCLUSION: Air-perfused vitrectomy showed comparable anatomic and functional success rates and shorter surgical time, compared with conventional vitrectomy in diabetic eyes with severe fibrovascular membranes. We suppose that the shortened surgical time in the air vitrectomy group is related to less intraoperative bleeding and more efficient hemostasis.


Assuntos
Ar , Retinopatia Diabética/cirurgia , Tamponamento Interno , Membrana Epirretiniana/cirurgia , Complicações Intraoperatórias , Vitrectomia/métodos , Hemorragia Vítrea/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos
6.
Graefes Arch Clin Exp Ophthalmol ; 256(1): 39-47, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29030692

RESUMO

PURPOSE: The purpose of this study was to compare the changes in the aqueous cytokine levels after intravitreal bevacizumab with those after combined intravitreal bevacizumab and subtenon triamcinolone injection in diabetic macular edema (DME). METHODS: This study examined 24 eyes of 23 patients with DME. Each patient with DME received randomly either an intravitreal injection of bevacizumab (IVBe) or IVBe with a subtenon triamcinolone injection (IVBe + STTA). Best corrected visual acuity and foveal thickness were evaluated and aqueous samples were obtained before and 4 weeks after the injection. The aqueous concentrations of interleukin (IL)-6, IL-8, interferon-induced protein (IP)-10, monocyte chemotactic protein (MCP)-1, platelet-derived growth factor (PDGF)-AA, and vascular endothelial growth factor (VEGF) were measured using a multiplex bead assay. RESULTS: After the injection, the foveal thickness decreased more in the IVBe + STTA group than in the IVBe group (P = 0.042). The MCP-1, PDGF-AA, and VEGF levels decreased significantly in the IVBe + STTA group (p = 0.013, p = 0.004 and p = 0.018 respectively), but only the VEGF level decreased in the IVBe group (p = 0.001). IL-8 was significantly increased in the IVBe + STTA group (p = 0.003) but the changes in the VEGF levels were smaller than in the IVBe group (p = 0.025). CONCLUSION: Intravitreal bevacizumab and subtenon triamcinolone injection reduces the VEGF, MCP-1 and PDGF-AA levels and increases the IL-8 level in the plural cytokine profiles of patients with DME, which might explain the limited therapeutic effect of combination therapy.


Assuntos
Humor Aquoso/metabolismo , Bevacizumab/administração & dosagem , Citocinas/metabolismo , Retinopatia Diabética/complicações , Edema Macular/metabolismo , Triancinolona Acetonida/administração & dosagem , Adulto , Idoso , Inibidores da Angiogênese/administração & dosagem , Retinopatia Diabética/diagnóstico por imagem , Retinopatia Diabética/metabolismo , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Injeções Intraoculares , Injeções Intravítreas , Macula Lutea/patologia , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cápsula de Tenon , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual
7.
J Neurosci ; 37(17): 4635-4644, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28373392

RESUMO

Upon degeneration of photoreceptors in the adult retina, interneurons, including bipolar cells, exhibit a plastic response leading to their aberrant rewiring. Photoreceptor reintroduction has been suggested as a potential approach to sight restoration, but the ability of deafferented bipolar cells to establish functional synapses with photoreceptors is poorly understood. Here we use photocoagulation to selectively destroy photoreceptors in adult rabbits while preserving the inner retina. We find that rods and cones shift into the ablation zone over several weeks, reducing the blind spot at scotopic and photopic luminances. During recovery, rod and cone bipolar cells exhibit markedly different responses to deafferentation. Rod bipolar cells extend their dendrites to form new synapses with healthy photoreceptors outside the lesion, thereby restoring visual function in the deafferented retina. Secretagogin-positive cone bipolar cells did not exhibit such obvious dendritic restructuring. These findings are encouraging to the idea of photoreceptor reintroduction for vision restoration in patients blinded by retinal degeneration. At the same time, they draw attention to the postsynaptic side of photoreceptor reintroduction; various bipolar cell types, representing different visual pathways, vary in their response to the photoreceptor loss and in their consequent dendritic restructuring.SIGNIFICANCE STATEMENT Loss of photoreceptors during retinal degeneration results in permanent visual impairment. Strategies for vision restoration based on the reintroduction of photoreceptors inherently rely on the ability of the remaining retinal neurons to correctly synapse with new photoreceptors. We show that deafferented bipolar cells in the adult mammalian retina can reconnect to rods and cones and restore retinal sensitivity at scotopic and photopic luminances. Rod bipolar cells extend their dendrites to form new synapses with healthy rod photoreceptors. These findings support the idea that bipolar cells might be able to synapse with reintroduced photoreceptors, thereby restoring vision in patients blinded by retinal degeneration.


Assuntos
Células Bipolares da Retina/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Sinapses/fisiologia , Visão Ocular/fisiologia , Animais , Dendritos/fisiologia , Denervação , Processamento de Imagem Assistida por Computador , Plasticidade Neuronal , Neurônios Aferentes/fisiologia , Coelhos , Células Fotorreceptoras Retinianas Cones/fisiologia , Vias Visuais
8.
Int J Ophthalmol ; 9(5): 717-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27275428

RESUMO

AIM: To evaluate the axial length (AXL) in unilateral idiopathic central serous chorioretinopathy (CSC). METHODS: This retrospective case-control study was comprised of a consecutive case series of 35 patients with acute unilateral idiopathic CSC, and age- and sex-matched 50 control eyes. AXL of both eyes of unilateral CSC patients and the control eyes were investigated. AXL was measured by ultrasonic biometry, and the adjusted AXL was calculated for CSC eyes as measured AXL plus differences of foveal thickness between CSC and normal fellow eyes in millimeters. The main outcome measures were comparison of AXL between CSC, fellow and control eyes. RESULTS: The mean age of 35 CSC patients was 45.5y, and 31 males were included. The adjusted AXL of CSC eyes was 23.52 mm, and the AXL of fellow eyes was 23.46 mm, and of control eyes 23.94 mm. The AXL of both CSC and fellow eyes were significantly shorter than control eyes (CSC vs control, P=0.044; fellow vs control, P=0.026). There was no statistically significant difference in AXL between CSC and fellow eyes. CONCLUSION: In unilateral idiopathic CSC, the AXL of CSC and fellow eyes are shorter than that of control eyes. Short AXL may be related with choroidal circulation abnormality in CSC.

9.
Invest Ophthalmol Vis Sci ; 57(6): 2488-500, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27159441

RESUMO

PURPOSE: Retinal photocoagulation and nondamaging laser therapy are used for treatment of macular disorders, without understanding of the response mechanism and with no rationale for dosimetry. To establish a proper titration algorithm, we measured the range of tissue response and damage threshold. We then evaluated safety and efficacy of nondamaging retinal therapy (NRT) based on this algorithm for chronic central serous chorioretinopathy (CSCR) and macular telangiectasia (MacTel). METHODS: Retinal response to laser treatment below damage threshold was assessed in pigmented rabbits by expression of the heat shock protein HSP70 and glial fibrillary acidic protein (GFAP). Energy was adjusted relative to visible titration using the Endpoint Management (EpM) algorithm. In clinical studies, 21 eyes with CSCR and 10 eyes with MacTel were treated at 30% EpM energy with high spot density (0.25-diameter spacing). Visual acuity, retinal and choroidal thickness, and subretinal fluid were monitored for 1 year. RESULTS: At 25% EpM energy and higher, HSP70 was expressed acutely in RPE, and GFAP upregulation in Müller cells was observed at 1 month. Damage appeared starting at 40% setting. Subretinal fluid resolved completely in 81% and partially in 19% of the CSCR patients, and visual acuity improved by 12 ± 3 letters. Lacunae in the majority of MacTel patients decreased while preserving the retinal thickness, and vision improved by 10 letters. CONCLUSIONS: Heat shock protein expression in response to hyperthermia helps define the therapeutic window for NRT. Lack of tissue damage enables high-density treatment to boost clinical efficacy, therapy in the fovea, and retreatments to manage chronic diseases.


Assuntos
Terapia a Laser/métodos , Macula Lutea/cirurgia , Degeneração Macular/cirurgia , Acuidade Visual , Animais , Modelos Animais de Doenças , Análise de Elementos Finitos , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Proteínas de Choque Térmico HSP72/biossíntese , Humanos , Imuno-Histoquímica , Macula Lutea/metabolismo , Macula Lutea/patologia , Degeneração Macular/diagnóstico , Degeneração Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Coelhos , Fatores de Tempo , Tomografia de Coerência Óptica , Resultado do Tratamento
10.
Ophthalmic Surg Lasers Imaging Retina ; 47(2): 171-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26878451

RESUMO

BACKGROUND AND OBJECTIVE: Establish the surgical procedure for subretinal implantation of multiple photovoltaic arrays for the restoration of sight. MATERIALS AND METHODS: Multiple silicon photovoltaic arrays of 1 mm in diameter and 30 µm in thickness were implanted subretinally via single retinotomy in rabbits. Ophthalmoscopic imaging and optical coherence tomography (OCT) were used to validate the implants' placement. RESULTS: Vitrectomy, followed by subretinal fluid injection for retinal detachment and retinotomy, allowed accurate placement of seven modules in the bleb, covering approximately a 3.5-mm diameter area on the retina via a single 1.5-mm retinotomy. OCT confirmed complete reattachment of the retina over the implants. CONCLUSION: Subretinal implantation of multiple photovoltaic arrays via a single retinotomy, followed by their tiling, minimizes the scleral and retinal incisions and provides better fit to the spherical shape of the eye ball, compared to a single, larger module. Such minimally traumatic procedure can be performed with 20-gauge intraocular instruments.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Implantação de Prótese/métodos , Retina/cirurgia , Próteses Visuais , Animais , Microeletrodos , Coelhos , Retina/patologia , Descolamento Retiniano/patologia , Descolamento Retiniano/cirurgia , Tomografia de Coerência Óptica , Vitrectomia
11.
J Ophthalmol ; 2015: 486832, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25694824

RESUMO

Purpose. To compare the changes in corneal endothelial cells after pars plana Ahmed glaucoma valve (AGV) implantation with those after the anterior chamber AGV implantation for refractory glaucoma. Methods. The medical records of 18 eyes with pars plana implantation of AGV (ppAGV) were reviewed retrospectively and were compared with 18 eyes with the anterior chamber AGV (acAGV) implant. The preoperative and postoperative endothelial cells, intraocular pressure (IOP), and postoperative complications during the follow-up in both groups were compared. Results. The average follow-up was 18 months. The postoperative endothelial cells in the ppAGV and acAGV groups were 2044 ± 303 and 1904 ± 324, respectively (P = 0.25). The average percentage decrease in the endothelial cells in the ppAGV and acAGV groups at 18 months was 12.5% and 18.4%, respectively, and showed significant difference between the 2 groups (P = 0.01). No difference in IOP control and the number of postoperative glaucoma medications was observed between the 2 groups. Conclusions. Endothelial cell damage in the ppAGV group for refractory glaucoma appeared to be lower than that in the acAGV group. Therefore, pars plana implantation of AGV may be preferred as it may have lower level of endothelial cell damage while maintaining similar level of IOP control.

12.
Artigo em Inglês | MEDLINE | ID: mdl-25559513

RESUMO

BACKGROUND AND OBJECTIVE: The authors propose a novel trimanual vitreous surgery using assistant-adjusted endoillumination during 23-gauge sutureless vitrectomy for severe diabetic tractional retinal detachment (TRD) under noncontact wide-angle viewing system. MATERIALS AND METHODS: The trimanual sutureless vitrectomy under a wide-angle viewing system consisted of (1) a fourth-port microcannula in the inferior 6-o'clock position; (2) dynamic and specular illumination by an assistant-controlled light probe inserted through the fourth port; and (3) membrane dissection and bleeding control using two intraocular instruments. RESULTS: Six eyes of four patients who underwent trimanual diabetic vitrectomy were evaluated. Recurrent TRD was detected in one eye, and a second operation was performed. There were no intraoperative sclerotomy-related complications or postoperative hypotony, increased IOP, or endophthalmitis. Final anatomic and functional success was achieved in all six eyes. CONCLUSION: The trimanual technique is valuable for membrane dissection in severe diabetic TRD. The optimal and dynamic illumination provided a high-quality stereoscopic view under a wide-angle viewing system. Careful coordination between a surgeon and an assistant facilitates this technique.


Assuntos
Retinopatia Diabética/cirurgia , Iluminação/métodos , Microcirurgia/métodos , Descolamento Retiniano/cirurgia , Técnicas de Sutura , Vitrectomia/métodos , Adulto , Tamponamento Interno , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerostomia , Óleos de Silicone , Sucção
13.
Sci Rep ; 4: 4041, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24509565

RESUMO

A gate-controlled metal-semiconductor barrier modulation and its effect on carrier transport were investigated in two-dimensional (2D) transition metal dichalcogenide (TMDC) field effect transistors (FETs). A strong photoresponse was observed in both unipolar MoS2 and ambipolar WSe2 FETs (i) at the high drain voltage due to a high electric field along the channel for separating photo-excited charge carriers and (ii) at the certain gate voltage due to the optimized barriers for the collection of photo-excited charge carriers at metal contacts. The effective barrier height between Ti/Au and TMDCs was estimated by a low temperature measurement. An ohmic contact behavior and drain-induced barrier lowering (DIBL) were clearly observed in MoS2 FET. In contrast, a Schottky-to-ohmic contact transition was observed in WSe2 FET as the gate voltage increases, due to the change of majority carrier transport from holes to electrons. The gate-dependent barrier modulation effectively controls the carrier transport, demonstrating its great potential in 2D TMDCs for electronic and optoelectronic applications.

14.
Adv Mater ; 26(5): 765-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24167082

RESUMO

A highly stretchable hybrid nanogenerator has been developed using a micro-patterned piezoelectric polymer P(VDF-TrFE), PDMS-CNT composite, and graphene nanosheets. Mechanical and thermal energies are simultaneously harvested from a single cell of the device. The hybrid nanogenerator exhibits high robustness behavior even after 30% stretching and generates very stable piezoelectric and pyroelectric power outputs due to micro-pattern designing.

15.
Acta Ophthalmol ; 92(3): e217-24, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23889803

RESUMO

PURPOSE: To investigate the changes in the aqueous levels of various cytokines after intravitreal triamcinolone or bevacizumab for branch retinal vein occlusion (BRVO). METHODS: Twenty-four eyes with macular oedema associated with BRVO and six eyes of six patients undergoing cataract surgery participated in this study. Each patient with BRVO randomly received an intravitreal injection of either 4 mg triamcinolone or 1.25 mg bevacizumab. Aqueous samples were obtained before and 4 weeks after the intravitreal injection in the BRVO group and before surgery in the control group. Aqueous concentrations of 16 cytokines were measured via multiplex bead assay. RESULTS: Prior to the administration of the drugs, aqueous levels of interleukin (IL)-6, IL-8, IL-17 and vascular endothelial growth factor (VEGF) were significantly higher in the BRVO group than in the control group (p=0.044, p=0.013, p<0.001, and p=0.008, respectively). Between the control group and the BRVO group, no significant differences were noted between pre- and postinjection best-corrected visual acuity (p=0.60, p=0.54) and central foveal thickness (p=0.47, p=0.82). In the triamcinolone group, levels of IL-6, IL-17, IP-10, platelet-derived growth factor (PDGF)-AA and VEGF were reduced significantly (p=0.012, p<0.001, p<0.001, p=0.015, and p<0.001, respectively). But in bevacizumab group, only VEGF was significantly reduced (p<0.001). Between the IVTA group and the IVBe group, no significant differences in the changes in VEGF levels were noted (p=0.06). CONCLUSION: Triamcinolone injection reduces plural inflammatory cytokines in BRVO, while bevacizumab has no influence on other cytokines as selective anti-VEGF therapy. No differences in the therapeutic effect were noted between an inhibition of plural inflammatory cytokines and an inhibition of VEGF only.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Humor Aquoso/química , Citocinas/metabolismo , Edema Macular/tratamento farmacológico , Oclusão da Veia Retiniana/complicações , Triancinolona Acetonida/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Bevacizumab , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Injeções Intravítreas , Edema Macular/etiologia , Edema Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Retina/patologia , Oclusão da Veia Retiniana/tratamento farmacológico , Oclusão da Veia Retiniana/metabolismo , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual
16.
ACS Nano ; 7(9): 7931-6, 2013 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23924287

RESUMO

Atomically thin forms of layered materials, such as conducting graphene, insulating hexagonal boron nitride (hBN), and semiconducting molybdenum disulfide (MoS2), have generated great interests recently due to the possibility of combining diverse atomic layers by mechanical "stacking" to create novel materials and devices. In this work, we demonstrate field-effect transistors (FETs) with MoS2 channels, hBN dielectric, and graphene gate electrodes. These devices show field-effect mobilities of up to 45 cm(2)/Vs and operating gate voltage below 10 V, with greatly reduced hysteresis. Taking advantage of the mechanical strength and flexibility of these materials, we demonstrate integration onto a polymer substrate to create flexible and transparent FETs that show unchanged performance up to 1.5% strain. These heterostructure devices consisting of ultrathin two-dimensional (2D) materials open up a new route toward high-performance flexible and transparent electronics.

18.
Nanotechnology ; 24(17): 175402, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23558434

RESUMO

A tandem device which integrates a PVDF nanogenerator and silicon (Si) nanopillar solar cell is fabricated. The Si nanopillar solar cell was fabricated using a mask-free plasma etching technique and annealing process. The PVDF nanogenerator was stacked on top of the Si nanopillar solar cell using a spinning method. The optical properties and the device performance of nanowire solar cells have been characterized, and the dependence of device performance versus annealing time or method has been investigated. Furthermore, the PVDF nanogenerator was operated with a 100 dB sound wave and a 0.8 V peak to peak output voltage was generated. This tandem device can successfully harvest energy from both sound vibration and solar light, demonstrating its strong potential as a future ubiquitous energy harvester.

19.
Nat Commun ; 4: 1624, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23535645

RESUMO

Atomically thin two-dimensional materials have emerged as promising candidates for flexible and transparent electronic applications. Here we show non-volatile memory devices, based on field-effect transistors with large hysteresis, consisting entirely of stacked two-dimensional materials. Graphene and molybdenum disulphide were employed as both channel and charge-trapping layers, whereas hexagonal boron nitride was used as a tunnel barrier. In these ultrathin heterostructured memory devices, the atomically thin molybdenum disulphide or graphene-trapping layer stores charge tunnelled through hexagonal boron nitride, serving as a floating gate to control the charge transport in the graphene or molybdenum disulphide channel. By varying the thicknesses of two-dimensional materials and modifying the stacking order, the hysteresis and conductance polarity of the field-effect transistor can be controlled. These devices show high mobility, high on/off current ratio, large memory window and stable retention, providing a promising route towards flexible and transparent memory devices utilizing atomically thin two-dimensional materials.

20.
Retina ; 32(9): 1767-74, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22481480

RESUMO

PURPOSE: To compare rates of early postoperative hypotony and intraocular pressure (IOP) elevation between 23-gauge sutureless vitrectomies with and without phacoemulsification and intraocular lens implantation in patients with proliferative diabetic retinopathy. METHODS: This study reviewed the medical records of 302 eyes of patients who underwent primary 23-gauge sutureless vitrectomy for the complications of proliferative diabetic retinopathy. A case series of 207 eyes that underwent combined vitrectomy and cataract surgery (combined group) was compared with that of 95 eyes that underwent vitrectomy only (vitrectomy group): The eyes that remained phakic after the vitrectomy were excluded from this study. The main outcome measures were postoperative hypotony (IOP < 6 mmHg or IOP < 10 mmHg with choroidal detachment) and IOP elevation (>30 mmHg). RESULTS: Postoperative hypotony was identified in 4 (1.9%) of 207 eyes in combined group, but in 7 (7.4%) of 95 eyes in vitrectomy group (P = 0.048). Rate of IOP elevation was very low and not different between the two groups. The multivariate analysis showed that vitrectomy without cataract surgery was associated with the postoperative hypotony (odds ratio = 4.6, P = 0.045). CONCLUSION: The incidence of early postoperative hypotony was lower in combined sutureless vitrectomy and cataract surgery than in sutureless vitrectomy alone and that of IOP elevation was very low in both groups. The maintenance of a stable IOP with a low risk of IOP fluctuation may be an additional advantage of sutureless diabetic vitrectomy combined with cataract surgery.


Assuntos
Retinopatia Diabética/cirurgia , Pressão Intraocular/fisiologia , Implante de Lente Intraocular , Facoemulsificação , Complicações Pós-Operatórias , Vitrectomia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Hipotensão Ocular/etiologia , Hipotensão Ocular/fisiopatologia , Estudos Retrospectivos , Técnicas de Sutura , Tonometria Ocular , Acuidade Visual/fisiologia
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