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1.
Int J Mol Sci ; 25(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38892206

RESUMO

Sulfated marine polysaccharides, so-called fucoidans, have been shown to exhibit anti-inflammatory and immunomodulatory activities in retinal pigment epithelium (RPE). In this study, we tested the effects of different fucoidans (and of fucoidan-treated RPE cells) on retinal microglia to investigate whether its anti-inflammatory effect can be extrapolated to the innate immune cells of the retina. In addition, we tested whether fucoidan treatment influenced the anti-inflammatory effect of RPE cells on retinal microglia. Three fucoidans were tested (FVs from Fucus vesiculosus, Fuc1 and FucBB04 from Laminaria hyperborea) as well as the supernatant of primary porcine RPE treated with fucoidans for their effects on inflammatory activated (using lipopolysaccharide, LPS) microglia cell line SIM-A9 and primary porcine retinal microglia. Cell viability was detected with a tetrazolium assay (MTT), and morphology by Coomassie staining. Secretion of tumor necrosis factor alpha (TNFα), interleukin 1 beta (IL1ß) and interleukin 8 (IL8) was detected with ELISA, gene expression (NOS2 (Nitric oxide synthase 2), and CXCL8 (IL8)) with qPCR. Phagocytosis was detected with a fluorescence assay. FucBB04 and FVs slightly reduced the viability of SIM-A9 and primary microglia, respectively. Treatment with RPE supernatants increased the viability of LPS-treated primary microglia. FVs and FucBB04 reduced the size of LPS-activated primary microglia, indicating an anti-inflammatory phenotype. RPE supernatant reduced the size of LPS-activated SIM-A9 cells. Proinflammatory cytokine secretion and gene expression in SIM-A9, as well as primary microglia, were not significantly affected by fucoidans, but RPE supernatants reduced the secretion of LPS-induced proinflammatory cytokine secretion in SIM-A9 and primary microglia. The phagocytosis ability of primary microglia was reduced by FucBB04. In conclusion, fucoidans exhibited only modest effects on inflammatorily activated microglia by maintaining their cell size under stimulation, while the anti-inflammatory effect of RPE cells on microglia irrespective of fucoidan treatment could be confirmed, stressing the role of RPE in regulating innate immunity in the retina.


Assuntos
Sobrevivência Celular , Microglia , Polissacarídeos , Epitélio Pigmentado da Retina , Microglia/efeitos dos fármacos , Microglia/metabolismo , Animais , Polissacarídeos/farmacologia , Suínos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/citologia , Sobrevivência Celular/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Retina/efeitos dos fármacos , Retina/metabolismo , Retina/citologia , Linhagem Celular , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo
2.
Cornea ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38900711

RESUMO

PURPOSE: The treatment of patients with relapsed/refractory multiple myeloma (RRMM) with the antibody-drug conjugate belantamab mafodotin is affected by ocular adverse effects, most frequently keratopathy with corneal microcyst-like epithelial changes (MECs). To assess ocular side effects, the "Keratopathy and Visual Acuity (KVA) scale," based on the extent of keratopathy subjectively graded on slit-lamp examination and the change in best corrected visual acuity from baseline, was created. Advanced corneal imaging techniques have been explored to further characterize MECs and identify objective imaging biomarkers. We examined whether infrared reflectance imaging of the anterior segment (AS-IR) could contribute to the assessment, monitoring, and documentation of corneal toxicity in patients treated with belantamab mafodotin. METHODS: In addition to the KVA examination, AS-IR imaging was performed. AS-IR images were evaluated for presence of visible hyporeflective lesions and their spatial and temporal distribution between visits and compared with keratopathy identified on slit-lamp examination. To standardize the assessment, a scoring system for lesions on AS-IR was implemented for additional analysis. RESULTS: Nine patients undergoing treatment with belantamab mafodotin for up to 9 months were examined. All patients exhibited hyporeflective lesions on AS-IR imaging, indicative of corneal toxicity corresponding to MECs observed on slit-lamp examination. AS-IR lesions showed early occurrence, variable quantity and size, and distinct distribution patterns, correlating with clinical findings during treatment. CONCLUSIONS: As shown for belantamab mafodotin, AS-IR imaging represents a fast, noninvasive, supplemental method for documentation, monitoring, and assessment of corneal adverse effects during treatment with antibody-drug conjugates, which may enable more standardized analyses.

3.
Ophthalmologie ; 121(5): 391-396, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38446196

RESUMO

BACKGROUND: Neoplasms of the conjunctiva include many different entities with a broad variety of clinical presentations. This can make a precise clinical diagnosis difficult. R0 resection is the gold standard treatment for most malignant conjunctival neoplasms, but not every benign lesions must treated by excision. In clinical practice it is important to make an accurate clinical diagnosis to enable the best possible management of conjunctival neoplasms. OBJECTIVE: The aim of this study was to determine the accuracy of clinical diagnosis of neoplasms of the conjunctiva. MATERIALS AND METHODS: Within a retrospective design, the data from all patients with excision of a conjunctival lesion between 2011 and 2020 in the Department of Ophthalmology of the UKSH Campus Kiel were extracted and analyzed. The specificity, sensitivity, and positive and negative predictive value for the preoperative clinical rating of dignity and diagnosis were evaluated based on the histological diagnostic findings. RESULTS: Of 220 included cases, 75% were benign and 25% malignant. The most frequent neoplasm of the conjunctiva was benign conjunctival nevus. The sensitivity for clinical prediction of a benign lesion was 0.86 (95% confidence interval [CI] 0.59-0.92), the specificity 0.95 (CI 0.85-0.99), and the positive predictive value 0.98 (CI 0.94-1.0). The sensitivity for clinical prediction of malign dignity was 0.95 (CI 0.85-0.99), the specificity 0.88 (CI 0.83-0.93), and the positive predictive value 0.73 (CI 0.61-0.83). CONCLUSION: The derived values for clinical diagnosis of conjunctival neoplasms can be rated as good. However, in clinical practice, untypical lesions can be hard to diagnose correctly, and the clinical diagnosis should be carefully reviewed; if in doubt, excision should be preferred.


Assuntos
Neoplasias da Túnica Conjuntiva , Sensibilidade e Especificidade , Humanos , Neoplasias da Túnica Conjuntiva/patologia , Neoplasias da Túnica Conjuntiva/cirurgia , Neoplasias da Túnica Conjuntiva/diagnóstico , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Adulto Jovem , Adolescente , Idoso de 80 Anos ou mais , Túnica Conjuntiva/patologia , Túnica Conjuntiva/cirurgia , Criança , Valor Preditivo dos Testes
5.
Heliyon ; 9(4): e15202, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37123974

RESUMO

Age-related macular degeneration (AMD) is a multifactorial disease in which angiogenesis, oxidative stress and inflammation are important contributing factors. In this study, we investigated the anti-inflammatory effects of a fucoidan from the brown algae Fucus vesiculosus (FV) in primary porcine RPE cells. Inflammation was induced by lipopolysaccharide (LPS), polyinosinic:polycytidylic acid (Poly I:C), Pam2CSK4 (Pam), or tumor necrosis factor alpha (TNF-α). Cell viability was tested with thiazolyl blue tetrazolium bromide (MTT) test, barrier function by measuring transepithelial electric resistance (TEER), interleukin 6 (IL-6) and interleukin 8 (IL-8) secretion in ELISA, retinal pigment epithelium-specific 65 kDa protein (RPE65) and protectin (CD59) expression in Western blot, gene expression with quantitative polymerase chain reaction (qPCR) (IL6, IL8, MERTK, PIK3CA), and phagocytotic activity in a microscopic assay. FV fucoidan did not influence RPE cell viability. FV fucoidan reduced the Poly I:C proinflammatory cytokine secretion of IL-6 and IL-8. In addition, it decreased the expression of IL-6 and IL-8 in RT-PCR. LPS and TNF-α reduced the expression of CD59 in Western blot, this reduction was lost under FV fucoidan treatment. Also, LPS and TNF-α reduced the expression of visual cycle protein RPE65, this reduction was again lost under FV fucoidan treatment. Furthermore, the significant reduction of barrier function after Poly I:C stimulation is ameliorated by FV fucoidan. Concerning phagocytosis, however, the inflammation-induced reduction was not improved by FV fucoidan. FV and proinflammatory milieu did not relevantly influence phagocytosis relevant gene expression either. In conclusion, we show that fucoidan from FV can reduce proinflammatory stimulation in RPE induced by toll-like receptor 3 (TLR-3) activation and is of high interest as a potential compound for early AMD treatment.

6.
Int J Mol Sci ; 24(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175646

RESUMO

Fucoidans from brown algae are described as anti-inflammatory, antioxidative, and antiangiogenic. We tested two Saccharina latissima fucoidans (SL-FRO and SL-NOR) regarding their potential biological effects against age-related macular degeneration (AMD). Primary porcine retinal pigment epithelium (RPE), human RPE cell line ARPE-19, and human uveal melanoma cell line OMM-1 were used. Cell survival was assessed in tetrazolium assay (MTT). Oxidative stress assays were induced with erastin or H2O2. Supernatants were harvested to assess secreted vascular endothelial growth factor A (VEGF-A) in ELISA. Barrier function was assessed by measurement of trans-epithelial electrical resistance (TEER). Protectin (CD59) and retinal pigment epithelium-specific 65 kDa protein (RPE65) were evaluated in western blot. Polymorphonuclear elastase and complement inhibition assays were performed. Phagocytosis of photoreceptor outer segments was tested in a fluorescence assay. Secretion and expression of proinflammatory cytokines were assessed with ELISA and real-time PCR. Fucoidans were chemically analyzed. Neither toxic nor antioxidative effects were detected in ARPE-19 or OMM-1. Interleukin 8 gene expression was slightly reduced by SL-NOR but induced by SL-FRO in RPE. VEGF secretion was reduced in ARPE-19 by SL-FRO and in RPE by both fucoidans. Polyinosinic:polycytidylic acid induced interleukin 6 and interleukin 8 secretion was reduced by both fucoidans in RPE. CD59 expression was positively influenced by fucoidans, and they exhibited a complement and elastase inhibitory effect in cell-free assay. RPE65 expression was reduced by SL-NOR in RPE. Barrier function of RPE was transiently reduced. Phagocytosis ability was slightly reduced by both fucoidans in primary RPE but not in ARPE-19. Fucoidans from Saccharina latissima, especially SL-FRO, are promising agents against AMD, as they reduce angiogenic cytokines and show anti-inflammatory and complement inhibiting properties; however, potential effects on gene expression and RPE functions need to be considered for further research.


Assuntos
Laminaria , Degeneração Macular , Humanos , Animais , Suínos , Epitélio Pigmentado da Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Laminaria/metabolismo , Peróxido de Hidrogênio/metabolismo , Interleucina-8/metabolismo , Degeneração Macular/tratamento farmacológico , Degeneração Macular/metabolismo
7.
Exp Eye Res ; 231: 109469, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37037364

RESUMO

PURPOSE: Age-related macular degeneration (AMD) is the leading cause of severe vision loss in industrialized nations. Important factors in pathogenesis are oxidative stress, inflammation, and, in the wet form of AMD, angiogenesis. Fucoidans, sulfated polysaccharides from brown algae, may have antioxidant, anti-inflammatory, and antiangiogenic effects. In this study, we established specific gene expression panels for inflammation, oxidative stress and angiogenesis in porcine retinal pigment epithelium (RPE), and investigated the effect of fucoidans on gene expression under different noxious agents. METHODS: Primary porcine RPE cells cultured for at least 14 days were used. Using viability assays with tetrazolium bromide and real-time polymerase chain reaction of marker genes, positive controls were established for appropriate concentrations and exposure times of selected noxious agents (lipopolysaccharide (LPS), H2O2, CoCl2). Three different AMD relevant gene panels specific for porcine RPE for inflammation, oxidative stress, and angiogenesis were established, and the influence of fucoidans (mainly Fucus vesiculosus; FV) on gene expression was investigated. RESULTS: The following was shown by gene expression analyses: (1) Inflammation panel: Expression of 18 genes was affected under LPS (three days). Among them, LPS increased genes for interleukin 1 receptor 2, interleukin 8, cyclooxygenase-2 and vascular cell adhesion protein 1 expression which were diminished when FV was present. (2) Oxidative stress panel: Under stimulation of H2O2 (one day) and LPS (one day), expression of a total of 15 genes was affected. LPS induced increase in genes for superoxide dismutase-1, C-X-C motif chemokine 10, and CC chemokine ligand-5 expression was not detected when FV was present. (3) Angiogenesis panel: Under stimulation with CoCl2 (three days) expression of six genes was affected, with the increase of genes for angiopoietin 2, vascular endothelial growth factor receptor-1, and follistatin being diminished when FV was present. CONCLUSION: Three specific gene expression panels for porcine RPE that map genes for three of the major pathological factors of AMD, inflammation, oxidative stress, and angiogenesis, were established. Further, we demonstrated that fucoidans can reduce stress related gene activation in all of these three major pathogenic pathways. This study is another indication that fucoidans can act on different pathomechanisms of AMD simultaneously, which provides further evidence for fucoidans as a possible drug for treatment and prevention of AMD.


Assuntos
Degeneração Macular , Epitélio Pigmentado da Retina , Animais , Suínos , Epitélio Pigmentado da Retina/metabolismo , Lipopolissacarídeos/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Peróxido de Hidrogênio/metabolismo , Degeneração Macular/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Polissacarídeos/uso terapêutico , Estresse Oxidativo , Inflamação/metabolismo , Expressão Gênica
8.
Int J Mol Sci ; 24(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36768552

RESUMO

Fucoidans are polysaccharides and constituents of cell walls of brown algae such as Laminaria hyperborea (LH). They exhibit promising effects regarding age-related macular degeneration (AMD). However, the safety of this compound needs to be assured. The focus of this study lies on influences of an LH fucoidan on the retinal pigment epithelium (RPE). The high-molecular weight LH fucoidan Fuc1 was applied to primary porcine RPE cells, and a tetrazolium (MTT) cell viability assay was conducted. Further tests included a scratch assay to measure wound healing, Western blotting to measure expression of retinal pigment epithelium-specific 65 kDa protein (RPE65), as well as immunofluorescence to measure uptake of opsonized fluorescence beads into RPE cells. Lipopolysaccharide was used to proinflammatorily activate the RPE, and interleukin 6 (IL-6) and interleukin 8 (IL-8) secretion was measured. RPE/choroid cultures were used to assess vascular endothelial growth factor (VEGF) secretion. Real-time polymerase chain reaction (real-time PCR) was performed to detect the gene expression of 91 different genes in a specific porcine RPE gene array. Fuc1 slightly reduced wound healing, but did not influence cell viability, phagocytosis or RPE65 expression. Fuc1 lowered IL-6, IL-8 and VEGF secretion. Furthermore, Fuc1 did not change tested RPE genes. In conclusion, Fuc1 does not impair RPE cellular functions and shows antiangiogenic and anti-inflammatory activities, which indicates its safety and strengthens its suitability concerning ocular diseases.


Assuntos
Laminaria , Epitélio Pigmentado da Retina , Suínos , Animais , Epitélio Pigmentado da Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Laminaria/metabolismo , Interleucina-8/metabolismo , Peso Molecular , Interleucina-6/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Células Cultivadas
9.
Antioxidants (Basel) ; 11(8)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36009293

RESUMO

Ommochromes are pigments of invertebrates that exhibit oxidative stress protection. The aim of this study was to investigate ommochromes extracted from cephalopod's skin for their ability to inhibit age-related-macular degeneration (AMD)-related factors such as H2O2-induced and iron-dependent oxidative stress (ferroptosis and erastin), accumulation of advanced glycation end-products (AGEs), as well as vascular endothelial growth factor (VEGF), and inflammatory cytokines (interleukin 6 and interleukin 8) secretion. As cell systems, we used primary porcine retinal pigment epithelium (RPE), human retinal pigment epithelium cell line ARPE-19 and uveal melanoma cell line OMM-1. In vitro, ommochromes produced an antiglycation effect by the inhibition of fructosylation reaction. The ommochromes showed protective effects against erastin- induced cell death in ARPE-19. In addition, in long-term stimulation (7 days) ommochromes decreased constitutively secreted VEGF, as well as interleukin 6 and interleukin 8 induced by Poly I:C in primary RPE. No relevant effects were detected in OMM-1 cells. The effects are dependent on the cell system, time of exposition, and concentration. This substance is of interest for further research concerning age-related macular degeneration.

10.
Ophthalmology ; 129(10): 1129-1141, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35680097

RESUMO

PURPOSE: Proliferative vitreoretinopathy (PVR) is the major cause for surgical failure after primary rhegmatogenous retinal detachment (RRD). So far, no therapy has been proven to prevent PVR. Promising results for 5-fluorouracil (5-FU) and low-molecular weight heparin (LMWH) in high-risk eyes have been reported previously. The objective of this trial was to examine the effect of adjuvant intravitreal therapy with 5-FU and LMWH compared with placebo on incidence of PVR in high-risk patients with primary RRD. DESIGN: Randomized, double-blind, controlled, multicenter, interventional trial with 1 interim analysis. PARTICIPANTS: Patients with RRD who were considered to be at high risk for PVR were included. Risk of PVR was assessed by noninvasive aqueous flare measurement using laser flare photometry. METHODS: Patients were randomized 1:1 to verum (200 mg/ml 5-FU and 5 IU/ml dalteparin) and placebo (balanced salt solution) intravitreally applied during routine pars plana vitrectomy. MAIN OUTCOME MEASURES: Primary end point was the development of PVR grade CP (full-thickness retinal folds or subretinal strands in clock hours located posterior to equator) 1 or higher within 12 weeks after surgery. For grading, an end point committee assessed fundus photographs. Secondary end points included best-corrected visual acuity and redetachment rate. A group sequential design with 1 interim analysis was applied using the O'Brien and Fleming boundaries. Proliferative vitreoretinopathy grade CP incidence was compared using a Mantel-Haenszel test stratified by surgeon. RESULTS: A total of 325 patients in 13 German trial sites had been randomized (verum, n = 163; placebo, n = 162). In study eyes, mean laser flare was 31 ± 26 pc/ms. No significant difference was found in PVR rate. Primary analysis in the modified intention-to-treat population results were: verum 28% vs. placebo 23% (including not assessable cases as failures); odds ratio [OR], 1.25; 95% confidence interval [CI], 0.76-2.08; P = 0.77. Those in the per-protocol population were: 12% vs. 12%; OR, 1.05; 95% CI, 0.47-2.34; P = 0.47. None of the secondary end points showed any significant difference between treatment groups. During the study period, no relevant safety risks were identified. CONCLUSIONS: Rate of PVR did not differ between adjuvant therapy with 5-FU and LMWH and placebo treatment in eyes with RRD.


Assuntos
Descolamento Retiniano , Vitreorretinopatia Proliferativa , Dalteparina/uso terapêutico , Método Duplo-Cego , Fluoruracila , Heparina/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Descolamento Retiniano/cirurgia , Vitrectomia/efeitos adversos , Vitreorretinopatia Proliferativa/tratamento farmacológico , Vitreorretinopatia Proliferativa/etiologia , Vitreorretinopatia Proliferativa/prevenção & controle
11.
Exp Eye Res ; 219: 109063, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35385758

RESUMO

Properties of retinal pigment epithelium (RPE) are relevant for the development of cell culture models concerning an exact reproduction of the ocular cell biology. Here, we want to investigate how different carrier materials and coatings influence proliferation, differentiation and functions of RPE in regard to development of a three-dimensional cell culture model based on primary porcine RPE. Human RPE cell line ARPE-19 and primary porcine RPE were used. Cells were cultivated on plates which were coated with collagen I, collagen IV, laminin or fibronectin, respectively, and cell numbers were assessed after different time periods via trypan blue staining. Also, the ARPE-19 were cultivated on polydimethylsiloxane (PDMS), alginate, gelatin methacrylate (GelMA), poly-N-isopropylacrylamide (PNIPAM) and cells number were assessed. Primary RPE were cultured on PDMS material. Supernatants were collected and analyzed via ELISA for their vascular endothelial growth factor (VEGF) and transforming growth factor ß (TGF-ß) content. After day 14 cells were lysed and retinal pigment epithelium-specific 65 kDa protein (RPE65) and bestrophin-1 (BEST1) expression was investigated via Western blot. Cellular functions were tested on collagen I, collagen IV, laminin and fibronectin with and without PDMS. Scratch assay was performed to detect wound healing 24 and 48 h after scratch application. Immunolabeling was used to highlight tight junctions in concert with Hoechst staining and phalloidin to label cell nuclei and actin filaments, respectively. Phagocytosis of fluorescently labeled latex beads opsonized with photoreceptor outer segments (POS) was assessed via fluorescence microscopy. Transepithelial electrical resistance was measured for detection of cellular barrier. Gene expression of RDH11 (retinol dehydrogenase 11), BEST1 (bestrophin 1) and TGFB1 (transforming growth factor beta 1) was investigated via real-time PCR. Only PDMS carrier material was appropriate for primary RPE and ARPE-19 cell cultivation. Coating of PDMS with laminin led to increased proliferation. In primary RPE, VEGF secretion was increased if PDMS was coated with laminin or fibronectin compared to uncoated PDMS. No significant changes in phagocytic ability and generation of tight junctions were detected between different coatings, but RPE65 expression was reduced on fibronectin coated PDMS. Laminin coating decreased TGF-ß and increased BEST1 protein expression. Also, RPE on collagen IV showed highest TEER on transwell plates. The genes RDH11 and TGFB1 were decreased when coated with collagen IV without PDMS as well as coated PDMS. Laminin and collagen IV coating led to an increased wound healing. Cultivation of RPE and ARPE-1 on PDMS is a possible alternative for cell culture models whereas alginate, GelMA and PNIPAM were not suitable. Coating with laminin increased the proliferation, wound healing and VEGF secretion of the cells. The results suggest that laminin coated PDMS as carrier material is suitable for the development of 3D culture model systems.


Assuntos
Epitélio Pigmentado da Retina , Fator A de Crescimento do Endotélio Vascular , Alginatos , Animais , Células Cultivadas , Colágeno/metabolismo , Fibronectinas/metabolismo , Laminina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Suínos , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Int J Comput Assist Radiol Surg ; 17(4): 699-710, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35239133

RESUMO

PURPOSE: The registration of medical images often suffers from missing correspondences due to inter-patient variations, pathologies and their progression leading to implausible deformations that cause misregistrations and might eliminate valuable information. Detecting non-corresponding regions simultaneously with the registration process helps generating better deformations and has been investigated thoroughly with classical iterative frameworks but rarely with deep learning-based methods. METHODS: We present the joint non-correspondence segmentation and image registration network (NCR-Net), a convolutional neural network (CNN) trained on a Mumford-Shah-like functional, transferring the classical approach to the field of deep learning. NCR-Net consists of one encoding and two decoding parts allowing the network to simultaneously generate diffeomorphic deformations and segment non-correspondences. The loss function is composed of a masked image distance measure and regularization of deformation field and segmentation output. Additionally, anatomical labels are used for weak supervision of the registration task. No manual segmentations of non-correspondences are required. RESULTS: The proposed network is evaluated on the publicly available LPBA40 dataset with artificially added stroke lesions and a longitudinal optical coherence tomography (OCT) dataset of patients with age-related macular degeneration. The LPBA40 data are used to quantitatively assess the segmentation performance of the network, and it is shown qualitatively that NCR-Net can be used for the unsupervised segmentation of pathologies in OCT images. Furthermore, NCR-Net is compared to a registration-only network and state-of-the-art registration algorithms showing that NCR-Net achieves competitive performance and superior robustness to non-correspondences. CONCLUSION: NCR-Net, a CNN for simultaneous image registration and unsupervised non-correspondence segmentation, is presented. Experimental results show the network's ability to segment non-correspondence regions in an unsupervised manner and its robust registration performance even in the presence of large pathologies.


Assuntos
Aprendizado Profundo , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Tomografia de Coerência Óptica
14.
Curr Eye Res ; 47(1): 127-134, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33998943

RESUMO

PURPOSE/AIM OF THE STUDY: Vascular endothelial growth factor (VEGF)-antagonists are given over long time periods in the clinic, but the long-term effects on retinal pigment epithelium (RPE) cells are not fully investigated. This study aims to investigate these effects with two clinical relevant VEGF antagonists, bevacizumab and aflibercept, on the function of primary RPE cells. MATERIALS AND METHODS: All tests were conducted with primary porcine RPE. Cells were stimulated with bevacizumab or aflibercept (both 250 µg/ml) for 1 day, 7 days or 4 weeks. Cell viability was tested in MTT Assay. Secretion of TGF-ß was tested in ELISA, phagocytosis in a microscopic assay, migration in a scratch assay, and expression of RPE65 in Western blot. Barrier function was tested for bevacizumab in transwell-cultured cells by measuring transepithelial electrical resistance for up to 3 days. RESULTS: Viability was reduced by both antagonists at all time points tested. TGF-ß secretion was not altered by any treatment. Phagocytosis was not significantly reduced by any treatment. Wound healing ability was not significantly altered by any treatment. The expression of RPE65 was reduced by bevacizumab but not aflibercept after 4 weeks. Transepithelial electrical resistance was not altered. CONCLUSIONS: Long-term treatment with anti VEGF may affect viability of RPE cells, and treatment with bevacizumab may have effects on RPE function in long-term treatment.


Assuntos
Bevacizumab/administração & dosagem , Epitélio Pigmentado da Retina/patologia , Degeneração Macular Exsudativa/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Animais , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Injeções Intravítreas , Fagocitose/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Suínos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/metabolismo
15.
Graefes Arch Clin Exp Ophthalmol ; 260(3): 857-872, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34643794

RESUMO

PURPOSE: Bevacizumab is taken up and transported through the retinal pigment epithelium. Inflammatory signaling may influence this interaction. In the present study, we have investigated the effect of pro-inflammatory stimuli on the uptake, intracellular localization, and transepithelial transport of bevacizumab. METHODS: ARPE-19 cell line or primary porcine RPE cells were treated with clinical relevant concentrations of bevacizumab (250 µg/ml). Pro-inflammatory signaling was induced by TLR-3 agonist polyinosinic:polycytidylic acid (Poly I:C). Viability was investigated with MTT and trypan-blue exclusion assay, and cell number, uptake, and intracellular localization were investigated with immunofluorescence, investigating also actin filaments, the motor protein myosin 7a and lysosomes. Immunofluorescence signals were quantified. Intracellular bevacizumab was additionally detected in Western blot. Barrier function was investigated with transepithelial resistant measurements (TER). The transepithelial transport of bevacizumab and its influence on cytokine (IL-6, IL-8, IL-1ß, TNFα) secretion was investigated with ELISA. RESULTS: Poly I:C in combination with bevacizumab reduced the viability of the cells. Treatment with Poly I:C reduced the uptake of bevacizumab, changed the intensity of the actin filaments, and reduced the colocalization with myosin 7a. In addition, Poly I:C reduced the capacity of RPE cells to transport bevacizumab over the barrier. In addition, bevacizumab reduced the secretion of IL-8 and TNFα after Poly I:C stimulation at selected time points. CONCLUSIONS: Pro-inflammatory activation of RPE cells with TLR-3 agonist Poly I:C changes the interaction of RPE cells with the anti-VEGF compound bevacizumab, reducing its uptake and transport. On the other hand, bevacizumab might influence pro-inflammatory cytokine release. Our data indicate that inflammation may influence the pharmacokinetic of bevacizumab in the retina.


Assuntos
Inibidores da Angiogênese , Epitélio Pigmentado da Retina , Inibidores da Angiogênese/farmacologia , Animais , Bevacizumab/farmacologia , Western Blotting , Células Cultivadas , Epitélio Pigmentado da Retina/metabolismo , Suínos
16.
Mar Drugs ; 19(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34677456

RESUMO

Fucoidans are algal polysaccharides that exhibit protective properties against oxidative stress. The aim of this study was to investigate different fucoidans from brown seaweeds for their ability to protect against iron-dependent oxidative stress (ferroptosis), a main hallmark of retinal and brain diseases, including hemorrhage. We investigated five new high-molecular weight fucoidan extracts from Fucus vesiculosus, F. serratus, and F. distichus subsp. evanescens, a previously published Laminaria hyperborean extract, and commercially available extracts from F. vesiculosus and Undaria pinnatifida. We induced oxidative stress by glutathione depletion (erastin) and H2O2 in four retinal and neuronal cell lines as well as primary cortical neurons. Only extracts from F. serratus, F. distichus subsp. evanescens, and Laminaria hyperborea were partially protective against erastin-induced cell death in ARPE-19 and OMM-1 cells, while none of the extracts showed beneficial effects in neuronal cells. Protective fucoidans also attenuated the decrease in protein levels of the antioxidant enzyme GPX4, a key regulator of ferroptosis. This comprehensive analysis demonstrates that the antioxidant abilities of fucoidans may be cell type-specific, besides depending on the algal species and extraction method. Future studies are needed to further characterize the health-benefiting effects of fucoidans and to determine the exact mechanism underlying their antioxidative abilities.


Assuntos
Antioxidantes/farmacologia , Fucus , Laminaria , Polissacarídeos/farmacologia , Organismos Aquáticos , Morte Celular/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio , Ferro , Neurônios , Estresse Oxidativo/efeitos dos fármacos , Retina
17.
J Glaucoma ; 30(3): e108-e113, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33750749

RESUMO

PRECIS: In eyes with intractable glaucoma, drainage devices provide long-term control of intraocular pressure also after penetrating keratoplasty (PK). There is a high incidence of corneal graft failure. PURPOSE: To compare very long-term results of eyes with glaucoma drainage device (GDD) after PK. METHODS: We retrospectively reviewed medical records of all patients who underwent GDD placement after PK at our institution between 2001 and 2017. Forty eyes of 40 patients were studied. Glaucoma outcome was assessed by postoperative intraocular pressure (IOP), number of medications, and need for further glaucoma surgery. Corneal outcome was assessed by graft rejection, failure, and visual acuity. Surgical procedures before and during the study period, and their complications were evaluated. RESULTS: The mean follow-up was 125.0±52.3 (median, 116.5) months. Twenty of 40 eyes had a follow-up of at least 10 years. The mean preoperative IOP was 34.0±8.3 (median, 32.0) mm Hg with 3.2±1.3 (median, 3.5) glaucoma medications. At last postoperative follow-up, the mean IOP decreased to 12.7±4.9 (median, 14.0) mm Hg with 1.0±1.2 (median, 0.0) glaucoma medications. GDD implantation successfully controlled glaucoma in 88%, 88%, 85%, 80%, 78%, 75%, and 70% of eyes, at 1, 2, 3, 4, 5, 7, and 10 years, respectively. At last follow-up 68% showed glaucoma success. The corneal grafts remained clear in 74%, 63%, 45%, 45%, 37%, 32%, and 26% of eyes at 1, 2, 3, 4, 5, 7, and 10 years, respectively. Only 7 corneal grafts (17.5%) remained clear at last follow-up. CONCLUSIONS: A GDD can successfully control intractable glaucoma even after a very long period of time also after PK. However, the survival of the corneal grafts is low.


Assuntos
Implantes para Drenagem de Glaucoma , Ceratoplastia Penetrante , Córnea , Seguimentos , Humanos , Pressão Intraocular , Estudos Retrospectivos , Resultado do Tratamento
18.
Biomolecules ; 11(1)2021 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467052

RESUMO

(1) Background: Retinal pigment epithelial cells (RPE) cells constitutively secrete vascular endothelial growth factor (VEGF) in the retina, protecting the neuronal cells and the choroid. Increased VEGF secretion, however, can result in neovascularization and edema. Many factors regulate VEGF secretion. In this study, we investigated the effect of external stimuli in relation to diurnal rhythm on constitutive VEGF secretion. (2) Methods: Single-eye RPE cell culture was prepared from porcine eyes. RPE cells were cultured in darkness, treated with daylight or room light, and treated with melatonin at different time frames, either respectively or in combination. Supernatants were collected and VEGF content evaluated using ELISA. Expression of the clock protein BMAL1 was evaluated with Western blot. (3) Results: VEGF secretion of the RPE shows a diurnal rhythm. While the rhythm is not influenced by either light or melatonin, the amount of secreted VEGF can be increased by nocturnal melatonin, especially in combination with morning daylight. These findings disclose another layer of VEGF regulation in the retina.


Assuntos
Células Epiteliais/metabolismo , Luz , Melatonina/farmacologia , Epitélio Pigmentado da Retina/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fatores de Transcrição ARNTL/metabolismo , Animais , Células Cultivadas , Ritmo Circadiano/fisiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/efeitos da radiação , Suínos
19.
Graefes Arch Clin Exp Ophthalmol ; 259(6): 1503-1511, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33346888

RESUMO

PURPOSE: The treatment guidelines for many macular diseases rely on frequent monitoring with optical coherence tomography (OCT). However, the burden of frequent disease control leads to low therapy adherence in real life. OCT home monitoring would address this issue but requires an inexpensive and self-operable device. With self-examination low-cost full-field OCT (SELFF-OCT), our group has introduced a novel technology that may fulfill both requirements. In this pilot study, we report the initial experiences with a clinical prototype. METHODS: Fifty-one patients with different macular diseases were recruited in a cross-sectional study. The most common diseases were age-related macular degeneration (AMD; 39/51), diabetic macular edema (DME; 6/51), and retinal vein occlusion (RVO; 3/51). Patients received a short training in device usage and then performed multiple self-scans with the SELFF-OCT device. For comparison, scans with a standard clinical spectral domain (SD-)OCT were taken. RESULTS: After a brief training, 77% of the patients were able to successfully acquire images that were clinically gradable. No significant influence on success could be found for age (p = 0.08) or BCVA (p = 0.97). Relevant disease biomarkers in the most common retinal diseases could be detected. CONCLUSIONS: SELFF-OCT was used successfully for retinal self-examination and in the future could be used for retinal home monitoring. Future improvements in technology are expected to improve success rates and image quality. TRIAL REGISTRATION: The Trial was registered in the German Trial Register under the number DRKS00013755 on 14.03.2018.


Assuntos
Retinopatia Diabética , Edema Macular , Doenças Retinianas , Estudos Transversais , Humanos , Edema Macular/diagnóstico , Projetos Piloto , Autoexame , Tomografia de Coerência Óptica
20.
Lasers Surg Med ; 53(3): 359-369, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32567146

RESUMO

BACKGROUND AND OBJECTIVES: The thermal stimulation therapy of the retinal pigment epithelium (TSR) is a sublethal laser technique for thermal stimulation of the retinal pigment epithelium (RPE)-Bruch's membrane (BrM)-complex. The aim of this study was to investigate the influence of TSR on the release of age-related macular degeneration (AMD)-relevant cell mediators. STUDY DESIGN/MATERIALS AND METHODS: Porcine RPE-BrM-choroid explants were irradiated with a 532 nm continuous wave laser using different spot sizes (100-300 µm, duration 100 milliseconds, 15-100 mW). Cell death was investigated by calcein staining. Explants were treated with grids of sublethal spots and cultivated in modified Ussing chambers. The effect on matrix metalloproteinase-2 (MMP-2) and -9 was investigated by zymography and quantitative reverse transcription polymerase chain reaction. Secretion of vascular endothelial growth factor (VEGF), pigment epithelium derived factor (PEDF), and transforming growth factor-ß (TGF-ß) was analyzed by enzyme-linked immunosorbent assay and expression of HSP70 was examined by western blot. Integrity of the RPE/BrM-complex was analyzed by scanning electron microscopy. RESULTS: Laser powers of 15 mW (100 µm) and 45 mW (300 µm) did not induce RPE cell death. The integrity of the RPE/BrM-complex was not impaired after TSR. After TSR with 300 µm spot size, we observed a significant increase of active MMP-2 in the basal compartments. The content of PEDF significantly increased in treated explants in both compartments with 100 and 300 µm spot sizes. VEGF and TGF-ß secretion was not triggered by TSR. CONCLUSIONS: TSR represents a possible RPE stimulating treatment for dry AMD. TSR increases the basal release of active MMP-2, which might reverse age-related thickening of BrM. VEGF secretion was not triggered by TSR while anti-angiogenic PEDF was increased, indicating an induction of an anti-angiogenic and neuroprotective environment. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.


Assuntos
Degeneração Macular , Epitélio Pigmentado da Retina , Animais , Células Cultivadas , Corioide , Degeneração Macular/terapia , Metaloproteinase 2 da Matriz , Suínos , Fator A de Crescimento do Endotélio Vascular
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