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1.
Int J Ophthalmol ; 15(11): 1736-1742, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36404978

RESUMEN

AIM: To assess alterations in growth factors, inflammatory mediators, and cytokines associated with vitreous-retinal diseases in vitreous humor from patients with proliferative diabetic retinopathy (PDR), and to identify potential new treatment targets and strategies. METHODS: Control vitreous samples were collected from patients with macular hole, epiretinal membranes, or rhegmatogenous retinal detachments, and PDR samples from patients with complications of PDR, who required pars plana vitrectomy. Specimens were stored at -80°C and then investigated by Luminex multi-factor assay. Parametric and nonparametric analyses of demographic characteristics and cytokine expression levels were conducted using SPSS. RESULTS: There were no significant differences in demographic characteristics between patients with and without PDR. Expression levels of growth factors [platelet-derived growth factor (PDGF)-AA, glial cell line-derived neurotrophic factor (GDNF), and vascular endothelial growth factor A (VEGFA)], inflammatory mediators [interleukin (IL)-8, IL-11, and tumor necrosis factor-α (TNF-α)] and cytokines [chemokine C-X-C ligand (CXCL)10, interferon-γ (IFN-γ), and granulocyte macrophage-colony stimulating factor (GM-CSF)] were significantly elevated in vitreous humor from patients with PDR compared with those in the control group (all P<0.05). Further, VEGFA levels were lower in patients with PDR treated with anti-VEGF injection than those who were not (P<0.05), and there was no difference between the PDR group treated with anti-VEGF and controls (P>0.05). CONCLUSION: This proof-of-concept study demonstrates the potential for combinational therapeutic strategies to ameliorate diabetic retinopathy progression by targeting growth factors, inflammatory factors, and cytokines, in addition to VEGFA.

2.
Int J Ophthalmol ; 14(7): 1025-1033, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34282387

RESUMEN

AIM: To quantitatively analyze the retinal intermediate and deep capillary plexus (ICP and DCP) in patients with retinal deep vascular complex ischemia (RDVCI), using 3D projection artifacts removal (3D PAR) optical coherence tomography angiography (OCTA). METHODS: RDVCI patients and gender- and age-matched healthy controls were assessed and underwent OCTA examinations. The parafoveal vessel density (PFVD) of retinal deep vascular complex (DVC), ICP, and DCP were analyzed, and the percentage of reduction (PR) of PFVD was calculated. RESULTS: Twenty-four eyes in 22 RDVCI patients (20 in acute phase and 4 in chronic phase) and 24 eyes of 22 healthy subjects were enrolled as the control group. Significant reduction of PFVD in DVC, ICP, and DCP was observed in comparison with the controls (DVC: acute: 43.59%±6.58% vs 49.92%±5.49%, PR=12.69%; chronic: 43.50%±3.33% vs 51.20%±3.80%, PR=15.04%. ICP: acute: 40.28%±7.91% vs 46.97%±7.14%, PR=14.23%; chronic: 41.48%±2.87% vs 46.43%±3.29%, PR=10.66%. DCP: acute: 45.44%±8.27% vs 51.51%±9.97%, PR=11.79%; chronic: 37.78%±3.48% vs 51.73%±5.17%, PR=26.97%; all P<0.05). No significant PR difference was found among DVC, ICP, and DCP of RDVCI in acute phase (P=0.812), but significant difference in chronic phase (P=0.006, DVC vs DCP, ICP vs DCP). No significant difference in PR between acute and chronic phases in the DVC (P=0.735) or ICP (P=0.681) was found, but significant difference in the DCP (P=0.041). CONCLUSION: The PFVD of DVC, ICP, and DCP in RDVCI is significantly decreased in both acute and chronic phases. ICP impairment is stabilized from acute to chronic phase in RDVCI, whereas subsequent DCP impairment is uncovered and can be explained by ischemia-reperfusion damage.

3.
Int J Ophthalmol ; 12(6): 1012-1020, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31236362

RESUMEN

AIM: To explore a segmentation algorithm based on deep learning to achieve accurate diagnosis and treatment of patients with retinal fluid. METHODS: A two-dimensional (2D) fully convolutional network for retinal segmentation was employed. In order to solve the category imbalance in retinal optical coherence tomography (OCT) images, the network parameters and loss function based on the 2D fully convolutional network were modified. For this network, the correlations of corresponding positions among adjacent images in space are ignored. Thus, we proposed a three-dimensional (3D) fully convolutional network for segmentation in the retinal OCT images. RESULTS: The algorithm was evaluated according to segmentation accuracy, Kappa coefficient, and F1 score. For the 3D fully convolutional network proposed in this paper, the overall segmentation accuracy rate is 99.56%, Kappa coefficient is 98.47%, and F1 score of retinal fluid is 95.50%. CONCLUSION: The OCT image segmentation algorithm based on deep learning is primarily founded on the 2D convolutional network. The 3D network architecture proposed in this paper reduces the influence of category imbalance, realizes end-to-end segmentation of volume images, and achieves optimal segmentation results. The segmentation maps are practically the same as the manual annotations of doctors, and can provide doctors with more accurate diagnostic data.

4.
Ying Yong Sheng Tai Xue Bao ; 29(12): 3927-3933, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30584718

RESUMEN

We examined fine root distribution dynamics at the depth of 0-40 cm soil profile for five varieties of Camellia oleifera, including "Ganwu 1", "Ganyong 5", "Changlin 4", "Changlin 40" and "Gan 447", in one year using minirhizotron technique. The temporal and spatial distribution characteristics of total root tip number (TRT), average root length density (ARLD) and average root diameter (ARD) were analyzed. The results showed that the TRT and ARLD changes of each variety were relatively stable in the second half of 2016, while there was a significant monthly fluctuation in the first half of 2017, especially for "Ganwu 1" and "Changlin 40". The TRT and ARLD of "Ganwu 1" peaked in May 2017, while the ARD of "Changlin 4" peaked in March 2017. The TRT and ARLD values of "Ganwu 1" and the ARD value of "Changlin 4" were significantly greater than those of other varieties during the whole observation period. The spatial distribution and monthly dynamics of fine roots varied significantly among different varieties of Camellia oleifera. The fine roots were mainly distributed at the soil layer of 0-20 cm for "Ganwu 1" and" Gan 447 ", but at 20-40 cm for " Changlin 4 "and " Changlin 40 ". The latter two varieties had relatively stable spatial distribution and monthly dynamics of fine roots when compared to others. In contrast, the root biomass of "Ganyong 5" was not significantly different between both soil layers despite a large spatial variation. The ARD of "Changlin 4" was significantly larger at the soil layer of 20-40 cm than that of 0-20 cm. There was no significant difference in ARD between both soil layers for other varieties. In conclusion, within the five varieties, "Ganwu 1" had the greatest biomass of fine roots, which were mainly distributed in the upper soil layer, while "Changlin 4" had the largest diameter of fine roots, which were mainly distributed in the lower soil layer.


Asunto(s)
Camellia/fisiología , Raíces de Plantas , Biomasa , Camellia/clasificación , Suelo
5.
Int J Ophthalmol ; 11(11): 1784-1795, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30450309

RESUMEN

AIM: To compare the clinical performance of 4 spectral-domain (SD) optical coherence tomography angiography (OCTA) systems: AngioVue™, AngioPlex™, Spectralis® OCTA, AngioScan, and 1 swept-source (SS) OCTA SS OCT Angio™. METHODS: Twenty-seven undilated right eyes of 27 participants underwent OCTA examination using five different systems respectively for both 3×3 and 6×6 mm2 scan pattern (Spectralis OCTA for 3×3 mm2 scan only). Image quality, including vessel valid visibility and the number of motion artifacts, and acquisition time were evaluated. Repeated measures analysis of variance (ANOVA) with Bonferroni's post-test and Friedman test with Dunn's post-test were used to compare measurements. RESULTS: The age of the subjects was 28.19±5.55y (range, 23-49y). The spherical equivalent refraction was -2.55±1.84 D (range, 0.00 to -5.25 D). Significant difference was observed in the evaluation of vessel valid visibility (AngioVue the highest: 0.111±0.031 for 3×3 mm2 scan and 0.128±0.020 for 6×6 mm2 scan), number of motion artifacts (AngioVue the fewest: 0.778±1.086 for 3×3 mm2 scan and 0.333±0.620 for 6×6 mm2 scan) and acquisition time (AngioPlex the shortest: 8.537±1.921s for 3×3 mm2 scan and 8.298±1.741s for 6×6 mm2 scan; all P<0.001). CONCLUSION: There is poor agreement of measurements among systems. AngioVue provides images with the highest vessel valid visibility and the fewest motion artifacts. AngioPlex achieves the shortest acquisition.

7.
Lasers Surg Med ; 49(3): 225-232, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28168812

RESUMEN

OBJECTIVE: The present study aimed to investigate the characteristics of macular telangiectasia type 1 (Mac tel type 1) using spectral-domain optical coherence tomography angiography (OCTA) and compare them with the characteristics of mild diabetic macular edema (DME), to provide a new objective method for quick clinical diagnosis and treatment. METHODS: A retrospective comparative analysis of 9 Mac tel type 1, 15 DME, and 15 normal eyes was performed using fluorescein angiography, spectral-domain optical coherence tomography, and OCTA. The morphological changes, retinal vessel density, and nonperfused areas were evaluated using split-spectrum amplitude-decorrelation angiography algorithm. RESULTS: OCTA revealed obvious saccular capillary telangiectasia and loss of parafoveal vascular density of Mac tel type 1. However, a number of line segment hyperreflective signals around the macula and more distinct nonperfusion in DME were observed. The quantitative foveal avascular zone mean area in Mac tel type 1 was larger than that in the normal eyes (0.40 ± 0.06 mm2 vs. 0.88 ± 0.19 mm2 , P < 0.001). However, the area in DME (1.52 ± 0.38 mm2 ) was larger than that in Mac tel type 1 (P < 0.001), and the foveal zone area in DME (1.127 ± 0.05 mm2 ) was also lager than it in Mac tel (P < 0.05). The vascular density of the superficial layer reduced in both Mac tel type 1 and DME (compared with normal eyes). The difference between Mac tel type 1 (49.56 ± 5.23)% and DME(44.58 ± 3.82)% was significant in the superficial capillary layer (P < 0.01). The vascular density of the retinal deep layer also reduced in both Mac tel type 1 and DME (compared with normal eyes). The difference between Mac tel type 1 (53.78 ± 7.36)% and DME (53.64 ± 4.96)% was no significant in this layer (P > 0.05). CONCLUSION: Morphological differences between Mac tel 1 and DME can be observed on OCTA. Superficial vascular density and non-perfusion area may serve as a quantitative method to identify them. Lasers Surg. Med. 49:225-232, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Angiografía con Fluoresceína/métodos , Edema Macular/diagnóstico , Telangiectasia Retiniana/diagnóstico , Tomografía de Coherencia Óptica/métodos , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/diagnóstico por imagen , Retinopatía Diabética/patología , Diagnóstico Diferencial , Femenino , Humanos , Edema Macular/diagnóstico por imagen , Edema Macular/patología , Masculino , Persona de Mediana Edad , Telangiectasia Retiniana/diagnóstico por imagen , Telangiectasia Retiniana/patología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Agudeza Visual
8.
J Ophthalmol ; 2016: 2989086, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27478633

RESUMEN

Objective. To observe the fellow eye in patients undergoing surgery on one eye for treating myopic traction maculopathy. Methods. 99 fellow eyes of consecutive patients who underwent unilateral surgery to treat MTM were retrospectively evaluated. All patients underwent thorough ophthalmologic examinations, including age, gender, duration of follow-up, refraction, axial length, intraocular pressure, lens status, presence/absence of a staphyloma, and best-corrected visual acuity (BCVA). Fundus photographs and SD-OCT images were obtained. When feasible, MP-1 microperimetry was performed to evaluate macular sensitivity and fixation stability. Results. At an average follow-up time of 24.7 months, 7% fellow eyes exhibited partial or complete MTM resolution, 68% stabilized, and 25% exhibited progression of MTM. Of the 38 eyes with "normal" macular structure on initial examination, 11% exhibited disease progression. The difference in progression rates in Groups 2, 3, and 4 was statistically significant. Refraction, axial length, the frequency of a posterior staphyloma, chorioretinal atrophy, initial BCVA, final BCVA, and retinal sensitivity all differed significantly among Groups 1-4. Conclusions. Long axial length, chorioretinal atrophy, a posterior staphyloma, and anterior traction contribute to MTM development. Patients with high myopia and unilateral MTM require regular OCT monitoring of the fellow eye to assess progression to myopic pre-MTM. For cases exhibiting one or more potential risk factors, early surgical intervention may maximize the visual outcomes.

9.
Ying Yong Sheng Tai Xue Bao ; 26(1): 1-8, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25985647

RESUMEN

Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition, however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear. A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5, pH 3.5, pH 2.5 and control. Rhizosihere and bulk soils were collected in the third year from the simulated acid deposition experiment. Soil mineral N, available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods, and N and P mineralization rates were estimated using the indoor aerobic incubation methods. Our results showed that compared to the control, the treatments of pH 4.5, pH 3.5 and pH 2.5, respectively decreased 7.1%, 42.1% and 49.9% NO3(-)-N, 6.4%, 35.9% and 40.3% mineral N, 10.5%, 41.1% and 46.9% available P, 18.7%, 30.1% and 44.7% ammonification rate, 3.6%, 12.7% and 38.8% net N-mineralization rate, and 31.5%, 41.8% and 63.0% P mineralization rate in rhizosphere soils; however, among the 4 treatments, rhizosphere soil nitrification rate was not significantly different, the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P<0.05). In bulk soil, compared with the control, the treatments of pH 4.5, pH 3.5 and pH 2.5 did not cause significant changes in NO3(-)-N, mineral N, available P as well as in the rates of nitrification, ammonification, net N-mineralization and P mineralization. With increasing the acid intensity, the rhizosphere effects of NH4+-N, NO3(-)-N, mineral N, ammonification and net N-mineralization rates were altered from positive to negative effects, those of urease and acid phosphatease showed the opposite trends, those of available P and P mineralization were negative and that of nitrification was positive. In sum, prolonged elevated acid rain could reduce N and P transformation rates, decrease their availability, alter their rhizosphere effects, and have impact on nutrient cycling in tea plantation.


Asunto(s)
Lluvia Ácida , Nitrógeno/química , Fósforo/química , Rizosfera , Suelo/química , Camellia sinensis , Nitrificación , Microbiología del Suelo , Ureasa/análisis
10.
BMC Ophthalmol ; 14: 98, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-25117955

RESUMEN

BACKGROUND: Valsalva retinopathy and traumatic macular hole are common conditions, but macular hole secondary to Valsalva retinopathy is rarely reported. CASE PRESENTATION: A 34-year-old healthy man suffered Valsalva retinopathy after doing push-up exercise. During his follow-up visits, the best-corrected visual acuity (BCVA) measurements, fundus examinations and spectral-domain optical coherence tomography (SD-OCT) tests were performed. Three months later, the premacular hemorrhage was noticeably absorbed with an improvement of visual acuity. SD-OCT showed a lamellar macular hole with intact but thickened internal limiting membrane (ILM) with vitreal tractions on surface of the macular. Nine months after the first visit, his vision acuity was 20/25. The fundus examination showed a complete absorption of the macular hemorrhage. SD-OCT showed that the lamellar macular hole has enlarged, with thickened ILM on the surface. Seventeen months after the onset, the BCVA, fundus examination results and OCT findings were stable. CONCLUSIONS: Macular hole secondary to Valsalva retinopathy had been rarely reported and its mechanism needs further understanding. SD-OCT can be used to observe the evolvement of Valsalva retinopathy.


Asunto(s)
Ejercicio Físico , Retina/patología , Perforaciones de la Retina/etiología , Maniobra de Valsalva , Adulto , Humanos , Masculino , Retina/cirugía , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía
11.
Heart ; 97(6): 479-84, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21296780

RESUMEN

BACKGROUND: Anti-angiotensin II receptor subtype 1 (AT1 receptor) autoantibodies have previously been shown in sera of hypertensive patients. This study assessed whether anti-AT1-receptor autoantibody in serum is correlated with the efficacy of an AT1-receptor blocker (ARB; candesartan)-based regimen in hypertensive patients after 8 weeks of treatment. DESIGN: The Study of Optimal Treatment in Hypertensive Patients with Anti-AT1-Receptor Autoantibodies is a multicentre, randomised, blinded endpoint, open-label, parallel-group comparison clinical trial conducted in five centres in Wuhan, China. Treatment is designed as stepwise added-on therapy to reduce blood pressure (BP) < 140/90 mm Hg. 512 patients with moderate to severe primary hypertension were randomly assigned to an 8-week treatment with either ARB (candesartan)-based regimen (n=257) or ACE inhibitor (imidapril)-based regimen (n=255). RESULTS: Systolic and diastolic BP was reduced significantly in both treatment groups. The candesartan-based regimen achieved a significantly greater systolic BP reduction than imdapril (30.8 ± 10.3 vs 28.8 ± 10.3 mm Hg, p = 0.023). In those anti-AT1 receptor autoantibody-positive hypertensive patients, the mean systolic BP at baseline was higher than in the anti-AT1 receptor autoantibody-negative group (160.5 ± 16.5 vs 156.2 ± 17.7 mm Hg; p = 0.006). The mean BP reduction was greater in the candesartan-based regimen than the imidapril-based regimen (-35.4 ± 9.8/16.9 ± 6.9 vs -29.4 ± 9.8/14.2 ± 6.9 mm Hg; p = 0.000 and 0.002, respectively), and more patients on imidapril required add-on medications to achieve BP control (94% vs 86%; p=0.03). No correlation was observed between the titre of anti-AT1 receptor autoantibody and the efficacy of candesartan-based therapy. In those anti-AT1 receptor autoantibody-negative patients similar BP lowering was reached in the candesartan and the imidapril-based regimens. CONCLUSIONS: An ARB-based regimen is more effective in BP lowering than an ACE inhibitor-based regimen in the presence of anti-AT1 receptor autoantibodies. Trial registration number This trial has been registered at http://www.register.clinicaltrials.gov/ (identifier: NCT00360763).


Asunto(s)
Antihipertensivos/uso terapéutico , Autoanticuerpos/sangre , Bencimidazoles/uso terapéutico , Hipertensión/tratamiento farmacológico , Imidazolidinas/uso terapéutico , Receptor de Angiotensina Tipo 1/inmunología , Tetrazoles/uso terapéutico , Adulto , Anciano , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antihipertensivos/efectos adversos , Bencimidazoles/efectos adversos , Compuestos de Bifenilo , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Femenino , Humanos , Hipertensión/inmunología , Hipertensión/fisiopatología , Imidazolidinas/efectos adversos , Masculino , Persona de Mediana Edad , Tetrazoles/efectos adversos , Resultado del Tratamiento
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