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1.
Int J Clin Pract ; 2023: 3880297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342617

RESUMO

Purpose: This study was carried out to evaluate the visual acuity (VA), complications, and prognosis of patients diagnosed with submacular hemorrhage (SMH) from polypoidal choroidal vasculopathy (PCV) and retinal arterial macroaneurysm (RAM) treated by pars plana vitrectomy (PPV), subretinal tissue plasminogen activator (tPA), and air tamponade in vitreous cavity. It facilitates the development of generic treatment methods that can be widely used to improve vision and treat potential complications in patients with SMH, regardless of the underlying pathophysiological condition, such as PCV or RAM. Methods: In this retrospective study, SMH patients were divided into two groups based on their diagnosis: (1) polypoidal choroidal vasculopathy (PCV) and (2) retinal arterial macroaneurysm (RAM). The visual recovery and complications of patients with PCV and RAM after PPV + tPA (subretinal) surgery were analyzed. Results: A total of 36 eyes of 36 patients were included: PCV (47.22%, 17/36) and RAM (52.78%, 19/36). The mean age of the patients was 64 years, and 63.89% of the patients (23/36) were female. The median VA was 1.85 logMAR before surgery, 0.93 and 0.98 logMAR at 1 and 3 months after surgery, respectively, indicating that most patients' vision improved after surgery. At the 1 and 3 months postoperative follow-up, each patient was diagnosed with rhegmatogenous retinal detachment at 1 month and 3 months postoperatively, and four patients had vitreous hemorrhage at 3 months postoperatively. Preoperatively, patients exhibited macular subretinal hemorrhage, retinal bulge, and exudation around the blood clot. Postoperatively, most patients showed dispersal of subretinal hemorrhage. Optical coherence tomography results revealed retinal hemorrhage involving the macula and hemorrhagic bulges under both the neuroepithelium and the pigment epithelium under the fovea preoperatively. After surgery, the air injected into the vitreous cavity was completely absorbed and the subretinal hemorrhage was dispersed. Conclusion: PPV combined with subretinal tPA injection and air tamponade in the vitreous cavity can facilitate modest visual recovery in patients with SMH due to PCV and RAM. However, some complications may occur, and their management remains challenging.


Assuntos
Macroaneurisma Arterial Retiniano , Ativador de Plasminogênio Tecidual , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Ativador de Plasminogênio Tecidual/uso terapêutico , Hemorragia Retiniana/etiologia , Hemorragia Retiniana/diagnóstico , Fibrinolíticos , Estudos Retrospectivos , Macroaneurisma Arterial Retiniano/complicações , Macroaneurisma Arterial Retiniano/tratamento farmacológico , Vasculopatia Polipoidal da Coroide , Prognóstico
2.
Sci Rep ; 12(1): 4258, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277581

RESUMO

To compare the efficacy of internal limiting membrane (ILM) flap covering to that of ILM flap insertion for the treatment of macular hole retinal detachment (MHRD) in highly myopic eyes with axial length (AL) ≥ 30 mm. We retrospectively analysed the medical records of 48 MHRD patients with high myopia (AL ≥ 30 mm). According to different surgical methods, the patients were divided into a covering group (23 eyes) and an insertion group (25 eyes). The rate of retinal reattachment and MH closure were compared between the two groups, and the related factors affecting the initial anatomical results were analysed. After primary vitrectomy and single silicone oil removal, there were 18 eyes (78.3%) in the covering group, and 20 eyes (80.0%) in the insertion group had retinal reattachment (P = 1.000). Moreover, 16 eyes (69.6%) in the covering group and 17 eyes (68.0%) in the insertion group had their MHs sealed (P = 0.907). The best-corrected visual acuity (BCVA) at 12 months and the improvement in BCVA postoperatively in the two groups were not statistically significant (P = 0.543, 0.955). Logistic regression analysis showed that elongated AL (OR = 1.844, 95% CI 1.037-3.280, P = 0.037) and higher choroidal atrophy (OR = 2.986, 95% CI 1.011-8.821, P = 0.048) were risk factors affecting initial anatomical success. For extremely high-myopia MHRD with AL ≥ 30 mm, ILM flap covering and insertion can both effectively seal the MH and promote retinal reattachment, but the visual function improvement may still be limited. The longer the AL and the higher the choroidal atrophy, the greater is the risk of initial anatomical failure.


Assuntos
Miopia , Descolamento Retiniano , Perfurações Retinianas , Atrofia/complicações , Membrana Basal , Humanos , Miopia/complicações , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Vitrectomia/métodos
3.
Med Sci Monit ; 28: e932996, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35001073

RESUMO

BACKGROUND The aim of this study was to assess use of lncRNAs as biomarkers in serum and aqueous humor of patients with diabetic macular edema (DME). MATERIAL AND METHODS Optical coherence tomography and fundus photography were used to analyze the retinal features of the patients. RT-qPCR was used to analyze the differential expression of lncRNA snhg5 in patients who have idiopathic macular hole (MH), DME, or refractory DME. The relationship between SNHG5 and the clinical characteristics of the patients was analyzed. The effect of SNHG5 on the hyperplasia and apoptosis of human retino-microvascular endothelial cells (HRMECs) and its mechanism were analyzed in vitro. RESULTS Patients with idiopathic MH developed retinal nerve epithelium rupture and retinal fundus thickening, and patients with DME or refractory DME showed significant macular edema with hemorrhaging. The refractory DME patients improved after treatment but still showed significant macular edema and multiple laser scarring. SNHG5 expression was not only low in the atrial fluid and plasma in DME patients, but also lower in the refractory DME group compared to the idiopathic MH patients. SNHG5 expression in the aqueous humor and plasma was negatively correlated with disease duration, body mass index, and levels of fasting blood glucose, glycated hemoglobin, proteinuria, and glycosuria. In the in vitro experiments, SNHG5 expression was significantly downregulated in high glucose-induced HMECs. After SNHG5 overexpression, cell proliferation, angiogenesis, and VEGF-A protein levels were distinctly downregulated. CONCLUSIONS SNHG5 correlates with the development of DME and is a potential target for therapy.


Assuntos
Humor Aquoso/metabolismo , Retinopatia Diabética , Células Endoteliais/metabolismo , Edema Macular/metabolismo , RNA Longo não Codificante , Fator A de Crescimento do Endotélio Vascular/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Retinopatia Diabética/sangue , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/fisiopatologia , Feminino , Angiofluoresceinografia/métodos , Perfilação da Expressão Gênica/métodos , Humanos , Edema Macular/diagnóstico , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/sangue , RNA Longo não Codificante/metabolismo , Retina/diagnóstico por imagem , Retina/patologia , Neovascularização Retiniana/diagnóstico por imagem , Neovascularização Retiniana/etiologia , Vasos Retinianos/patologia , Vasos Retinianos/fisiopatologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual
5.
Exp Ther Med ; 22(3): 975, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34335917

RESUMO

Diabetic macular edema (DME) is the main cause of visual impairment in diabetic patients, but its pathogenesis remains unclear. The purpose of the present study was to analyze the expression of microRNA (miR)-155-5p in patients with DME and its regulatory mechanism. A total of 72 patients diagnosed with DME and 17 with idiopathic macular hole (MH) were recruited. Among samples from patients with DME, 45 were DME and 27 were refractory DME, whereas patients with idiopathic MH served as the control group. Optical coherence tomography and fundus photograph analysis revealed that part of the retina in the fundus of patients with DME was thickened, with macular edema occurring simultaneously. In refractory patients with DME, macular edema was associated with bleeding and a dark cavity between retinal layers. Through reverse transcription-quantitative PCR analysis, miR-155-5p was highly expressed in the aqueous humor (AH) and plasma of patients with DME compared with that in patients with MH, and this was even higher in the refractory DME group. Upon analyzing patient clinical data, the difference in miR-155-5p expression in the AH and plasma was positively associated with disease course, body mass index, fasting blood-glucose, glycated hemoglobin, proteinuria and glycosuria. The expression of miR-155-5p was not significantly different based on hemoglobin, intraocular pressure and sex. The aforementioned results indicate that miR-155-5p might promote the development of DME. To further study the molecular mechanism, human retinal microvascular endothelial cells (HRMECs) were cultured and treated with high glucose in vitro. The results showed that miR-155-5p expression was significantly upregulated in HRMECs induced by high glucose. After inhibiting the expression of miR-155-5p, cell proliferation, angiogenesis and VEGF protein levels were significantly downregulated, whereas miR-155-5p mimics had the opposite effect. In summary, miR-155-5p is closely associated with DME and is a potential target for refractory DME treatment.

6.
Front Immunol ; 12: 659150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995378

RESUMO

Previous studies have established that disturbed lymphocytes are involved in the pathogenesis of Vogt-Koyanagi-Harada (VKH) syndrome. Accordingly, glucocorticoids (GCs), with their well-recognized immune-suppressive function, have been widely used for treatment of VKH patients with acute relapses. However, the systemic response of diverse immune cells to GC therapy in VKH is poorly characterized. To address this issue, we analyzed immune cell subpopulations and their phenotype, as well as cytokine profiles in peripheral blood from VKH patients (n=25) and health controls (HCs, n=21) by flow cytometry and luminex technique, respectively. For 16 patients underwent GC therapy (methylprednisolone, MP), the aforementioned measurements as well as the transcriptome data from patients before and after one-week's GC therapy were also compared to interrogate the systemic immune response to GC therapy. Lymphocyte composition in the blood was different in VKH patients and HCs. VKH patients had significantly higher numbers of T cells with more activated, polarized and differentiated phenotype, more unswitched memory B cells and monocytes, as compared to HCs. MP treatment resulted in decreased frequencies of T cells and NK cells, inhibited NK cell activation and T cell differentiation, and more profoundly, a marked shift in the distribution of monocyte subsets. Collectively, our findings suggest that advanced activation and differentiation, as well as dysregulated numbers of peripheral lymphocytes are the major immunological features of VKH, and GC therapy with MP not only inhibits T cell activation directly, but also affects monocyte subsets, which might combinatorically result in the inhibition of the pathogenic immune response.


Assuntos
Biomarcadores , Glucocorticoides/uso terapêutico , Imunofenotipagem , Imunossupressores/uso terapêutico , Síndrome Uveomeningoencefálica/diagnóstico , Síndrome Uveomeningoencefálica/tratamento farmacológico , Adulto , Autoimunidade , Estudos de Casos e Controles , Citocinas/metabolismo , Feminino , Glucocorticoides/administração & dosagem , Humanos , Imunossupressores/administração & dosagem , Leucócitos/imunologia , Leucócitos/metabolismo , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Resultado do Tratamento , Síndrome Uveomeningoencefálica/etiologia
7.
J Ophthalmol ; 2020: 6707239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32454991

RESUMO

BACKGROUND: Rhegmatogenous retinal detachment associated with choroidal detachment (RRDCD) is rare and the prognosis is poor. This retrospective study evaluated the effect of preoperative steroid on the clinical outcome of patients with RRDCD receiving 23-gauge pars plana vitrectomy (PPV). METHODS: Sixty-six patients (67 eyes) with diagnosed RRDCD underwent 23-gauge PPV. The patients assigned to receive systemic or subtenon injection of preoperative steroids were considered Group A (35 eyes) and did not receive are considered Control Group B (32 eyes). Most patients in Group A received subtenon injection of glucocorticoids. The cyclodialysis angle was measured with ultrasound biomicroscopy. Preoperative, intraoperative, and postoperative data were compared. RESULTS: The rates of retinal reattachment in Group A after the first and second operations were 68.8% (24/35 eyes) and 91.43% (32/35 eyes), respectively, which were not significantly different from that of Group B (78.1%, 25/32 eyes; 96.6%, 31/32 eyes). The logMAR (logarithm of the minimum angle of resolution) visual acuity in Group A (1.63 ± 0.75) was similar to that of Group B (1.34 ± 0.74). Postoperative intraocular pressure and ocular hypertension in Group A (17.94 ± 9.82 mmHg and 37.1%, respectively; 13/35 eyes) were comparable to that of Group B (20.93 ± 10.21 mmHg and 56.3%; 18/32 eyes). Logistic regression analysis showed that postoperative reattachment was negatively associated with preoperative cyclodialysis angle as measured with ultrasound biomicroscopy (P=0.048) but was not significantly associated with preoperative steroid use (P=0.907). CONCLUSIONS: Preoperative steroid use does not improve retinal reattachment and visual acuity in patients with RRDCD after 23-gauge PPV. Preoperative measurement of the cyclodialysis angle with ultrasound biomicroscopy may be useful for predicting clinical outcomes.

8.
Sci Rep ; 8(1): 14907, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297843

RESUMO

Concentrator photovoltaic (CPV) systems, where incident direct solar radiation is tightly concentrated onto high-efficiency multi-junction solar cells by geometric optical elements, exhibit the highest efficiencies in converting the sun's energy into electric power. Their energy conversion efficiencies are greatly limited, however, due to Fresnel reflection losses occurring at three air/optics interfaces in the most sophisticated dual-stage CPV platforms. This paper describes a facile one-step wet-etching process to create a nanoporous surface with a graded-index profile on both flat and curved glasses, with capabilities of achieving ~99% average transmission efficiency in a wide wavelength range from 380 nm to 1.3 µm and for a wide range of incident angles up to ±40° regardless of the polarization state of incident sunlight. The simplicity of the etching process remarkably increases their versatility in various optical elements that require unconventional form factors such as Fresnel lenses and microlens arrays, and/or demanding curvatures along with much reduced dimensions such as ball lenses. Etched glass surfaces on two-stage optical concentrating systems yield enhancements in total optical transmission efficiencies by 13.8% and in the photocurrent by 14.3%, as experimentally determined by measurements on microscale triple-junction solar cells. The presented strategy can be widely adapted in a variety of applications such as image sensors, display systems, and other optoelectronic devices.

9.
Proc Natl Acad Sci U S A ; 113(51): E8210-E8218, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27930331

RESUMO

Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme ("+" denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

10.
Int J Ophthalmol ; 8(4): 812-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26309884

RESUMO

AIM: To describe the distribution and determinants of ocular biometric parameters and to ascertain the relative importance of these determinants in a large population of adults in rural central China. METHODS: A population-based, cross-sectional study performed in rural central China included 1721 participants aged 40 or more years. Ocular biometrical parameters including axial length (AL), anterior chamber depth (ACD), radius of corneal curvature (K) and horizontal corneal diameter [white-to-white (WTW) distance] were measured using non-contact partial coherence interferometry [intraocular lens (IOL)-Master]. RESULTS: Ocular biometric data on 1721 participants with a average age of 57.0±8.7y were analyzed at last. The general mean AL, ACD, mean corneal curvature radius (MCR), WTW were 22.80±1.12, 2.96±0.36, 7.56±0.26 and 11.75±0.40 mm, respectively. The mean values of each parameter in 40 to 49, 50 to 59, 60 to 69, and 70 to 91 years age groups were as follows: AL, 22.77±0.87, 22.76±1.06, 22.89±1.41, 22.92±0.80 mm; ACD, 3.10±0.32, 2.98±0.34, 2.86±0.36, 2.77±0.35 mm; MCR, 7.58±0.25, 7.54±0.26, 7.55±0.26, 7.49±0.28 mm; WTW, 11.79±0.38, 11.75±0.40, 11.72±0.41, 11.67±0.41 mm. The AL, ACD, MCR and WTW were correlated with age and the AL was correlated with height and weight. CONCLUSION: Our findings can serve as an important normative reference for multiple purposes and may help to improve the quality of rural eye care.

11.
Phys Chem Chem Phys ; 15(47): 20434-7, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24113691

RESUMO

Layers of poly(methyl methacrylate) doped with the Eu complex Eu(DPEPO)(hfac)3 (EuDH) provide a means for down-shifting incident ultraviolet (UV) light into the visible range, with beneficial effects on the performance of solar cells, as demonstrated with thin-film InGaP devices formed by epitaxial liftoff. Experimental and computational results establish important aspects of gain and loss mechanisms in the UV range. Measurements show that InGaP cells with coatings of EuDH doped PMMA exhibit enhanced currents (8.68 mA cm(-2)) and power conversion efficiencies (9.48%), both due to increased responses at wavelengths between 300-360 nm.

12.
Environ Sci Technol ; 46(6): 3155-62, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22309044

RESUMO

Foods produced on soils impacted by antimony (Sb) mining activities are a potential health risk due to plant uptake of the contaminant metalloids (Sb) and arsenic (As). Here we report for the first time the chemical speciation of Sb in soil and porewater of flooded paddy soil, impacted by active Sb mining, and its effect on uptake and speciation in rice plants (Oryza sativa L. cv Jiahua). Results are compared with behavior and uptake of As. Pot experiments were conducted under controlled conditions in a climate chamber over a period of 50 days. In pots without rice plants, flooding increased both the concentration of dissolved Sb (up to ca. 2000 µg L(-1)) and As (up to ca. 1500 µg L(-1)). When rice was present, Fe plaque developing on rice roots acted as a scavenger for both As and Sb, whereby the concentration of As, but not Sb, in porewater decreased substantially. Dissolved Sb in porewater, which occurred mainly as Sb(V), correlated with Ca, indicating a solubility governed by Ca antimonate. No significant differences in bioaccumulation factor and translocation factor between Sb and As were observed. Greater relative concentration of Sb(V) was found in rice shoots compared to rice root and porewater, indicating either a preferred uptake of Sb(V) or possibly an oxidation of Sb(III) to Sb(V) in shoots. Adding soil amendments (olivine, hematite) to the paddy soil had no effect on Sb and As concentrations in porewater.


Assuntos
Antimônio/análise , Arsênio/análise , Oryza/metabolismo , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Adsorção , Antimônio/metabolismo , Arsênio/metabolismo , China , Monitoramento Ambiental , Ferro/química , Mineração , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo
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