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1.
Int J Ophthalmol ; 17(4): 607-609, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638252
2.
Artigo em Inglês | MEDLINE | ID: mdl-38466396

RESUMO

PURPOSE: This nationwide study aims to delineate the incidence and trends of rhegmatogenous retinal detachment (rRD) in Germany across 17 years (2005-2021). METHODS: We conducted a retrospective cohort study using data from the German Federal Statistics Office and the Institute for the Hospital Remuneration System (InEK). The dataset includes approximately 19 million annual inpatient admissions annually. Retinal detachment was identified through ICD-10 code H33.0. Adjusted incidence rates were estimated after excluding reoperation cases. We used R Statistical Software to calculate estimates to 2021, and Tableau for visualisation. RESULTS: From 2005 to 2021, Germany reported 332,650 rRD cases, with males consistently more affected. Adjusted incidence rose from 15.6 per 100,000 in 2005 to 24.8 in 2021. Variable annual percentage changes in incidence were noted, averaging 4.0% for males and 2.6% for females. The annual mean age of affected individuals ranged from 60.2 to 62 years, with a median age between 62 and 63, suggesting increasing diagnoses at younger ages. Hospital stays declined from 6 to 3.3 days, and higher management rates were observed in Saarland and Rhineland-Palatine. CONCLUSION: The study confirms an increasing incidence of rRD in Germany from 2005 to 2021, particularly among males. These findings call for further research to investigate the underlying causes. Collaboration among healthcare professionals, researchers, and policymakers is essential for effective management and improved visual outcomes.

3.
Bioelectromagnetics ; 45(4): 200-205, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38348555

RESUMO

A crucial aspect of IARC's evaluation of the relative carcinogenicity of agents is the communication of its conclusions. The present paper addressed the experimental risk perception literature pertaining to IARC's radiofrequency electromagnetic field evaluation communication, and derived specific recommendations for improving it.


Assuntos
Campos Eletromagnéticos , Neoplasias , Humanos , Campos Eletromagnéticos/efeitos adversos , Neoplasias/etiologia , Ondas de Rádio/efeitos adversos , Comunicação
4.
Retina ; 44(5): 764-773, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38181515

RESUMO

PURPOSE: Exploratory analysis associated with the prospective, multicenter, randomized PRIVENT trial. To characterize the associations between laser flare photometry and anatomical and epidemiological features of rhegmatogenous retinal detachment (RRD). METHODS: The authors measured laser flare values of all 3,048 prescreened patients excluding those with comorbidities. A mixed regression analysis evaluated the strength of the influencing factors like age, sex, lens status, and presence and extent of RRD on laser flare. RESULTS: Rhegmatogenous retinal detachment was more frequent in men (65.8%) than in women (34.2%, P < 0.001) and in right (52%) than in left eyes (48%, P = 0.045). Phakic RRD affected less quadrants and was less likely to be associated with macula-off status than pseudophakic RRD (48.4% vs. 58.0% macula off, 23% vs. 31% ≥3 quadrants, P < 0.001). Laser flare of affected eyes was significantly higher compared with fellow eyes (12.6 ± 15.2 vs. 8.3 ± 7.4 pc/ms, P < 0.001). The factors age, sex, lens status, presence of RRD, and the number of quadrants affected were independent influencing factors on laser flare. R 2 was 0.145 for phakic and 0.094 for pseudophakic eyes. CONCLUSION: The results indicate that there may be more factors affecting laser flare than previously assumed. This might limit flare as predictive value for PVR and retinal redetachment.


Assuntos
Fotometria , Descolamento Retiniano , Humanos , Descolamento Retiniano/diagnóstico , Masculino , Feminino , Estudos Prospectivos , Fotometria/métodos , Pessoa de Meia-Idade , Idoso , Acuidade Visual/fisiologia , Adulto , Lasers
5.
Adv Ophthalmol Pract Res ; 3(2): 63-66, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37846379
6.
Int J Ophthalmol ; 16(9): 1357-1360, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37724277
8.
Acta Ophthalmol ; 101(2): e215-e225, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36178238

RESUMO

PURPOSE: Descemet membrane endothelial keratoplasty (DMEK) accounts for >50% of all corneal transplants in Germany. So far, no data from such a large multicenter study have been published. METHODS: This retrospective study included 3200 DMEKs at seven departments performed for Fuchs endothelial corneal dystrophy (FECD) or bullous keratopathy (BK). We evaluated best corrected visual acuity (BCVA, logMAR), endothelial cell density (ECD, cells/mm2 ), minimal corneal thickness (CT, µm), rebubbling-, primary transplant failure- and immune reaction-rate. Changes over time were evaluated by linear mixed models for repeated measures and correlation with case number by center by weighted linear regression. RESULTS: For patients without vision-limiting comorbidities (74% of all analysed eyes, n = 2270), mean BCVA improved from 0.6 ± 0.4 logMAR to 0.2 ± 0.2 logMAR 6 months (p < 0.001, n = 1441) and 0.1 ± 0.2 logMAR 12 months (p = 0.001, n = 1402) postoperatively. BK- had a worse BCVA compared to FECD-patients (0.3 ± 0.5 vs. 0.1 ± 0.2 logMAR [p < 0.001] at 1 year). ECD declined from 2465 ± 259 cells/mm2 (n = 2876 preoperatively) to 1587 ± 433 cells/mm2 after 12 months (p < 0.001, n = 1237). Mean rebubbling rate was 0.4 ± 0.7/eye. 784 eyes (25%) received at least one rebubbling. More rebubblings correlated with a lower ECD, a worse BCVA, a higher CT, and higher transplant failure and rejection rates (p < 0.001, p = 0.013 for BCVA at 12 months). A single rebubbling did not influence the BCVA (p = 0.785). Graft failure rate was 3% (n = 67), rejection rate 1.5% (n = 48). CONCLUSION: Descemet membrane endothelial keratoplasty increases visual acuity with low transplant failure- and rejection-rates. FECD has a better outcome than BK. Since a quarter of all patients need a rebubbling, this should be included in the informed consent. Remarkably, one rebubbling has no influence on the outcome.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Distrofia Endotelial de Fuchs , Humanos , Endotélio Corneano/transplante , Estudos Retrospectivos , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Contagem de Células , Distrofia Endotelial de Fuchs/cirurgia , Lâmina Limitante Posterior/cirurgia , Alemanha/epidemiologia , Resultado do Tratamento
9.
Regul Toxicol Pharmacol ; 136: 105282, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36328135

RESUMO

BACKGROUND: The difference between hazard and risk is crucial in risk assessment but rather unknown by non-experts. Hyper-partisan activists could use this knowledge gap to amplify risk perception by framing hazards as as-if risks, i.e., describing hazards as if their exposure is critical. Thus, using this as-if risk framing can trigger impressions that a risk is present. Until now, this framing technique and its rebuttal was not empirically analyzed. METHOD: An experimental 2 × 2 factorial online study (N = 404) with repeated measures after intervention was conducted to investigate how framing (hazard vs. as-if risk) and stigmatization (stigmatized vs. non-stigmatized chemical agent) affects affective and cognitive risk perception using an example of exposure to drifting pesticides. RESULTS: As-if risk framing increased risk perception, effects of stigmatization were not observed. However, the a-priori risk perception influences the recorded risk perceptions after the experimental treatment. Rebuttal was successful, i.e., subjects with elevated risk perceptions due to as-if risk framing reduced their risk perception after receiving corrective information. CONCLUSIONS: As-if risk framing investigated here is not a sequestered case. Accordingly, the present study may offer general insights into correcting biased information that neglects the difference between hazard and risk. Risk communicators can benefit from these insights.


Assuntos
Percepção , Humanos , Medição de Risco
10.
Int J Ophthalmol ; 15(10): 1567-1568, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262860
12.
Biomolecules ; 12(6)2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35740973

RESUMO

Dedifferentiation and proliferation of retinal pigment epithelial (RPE) cells are characteristics of retinal diseases. Dedifferentiation is likely associated with changes of inwardly rectifying potassium (Kir) channels. The roles of Kir4.2 channels in viability, and proliferation of cultured RPE cells were investigated. Gene expression levels were determined using qRT-PCR. RPE cells expressed Kir2.1, 2.2, 2.4, 3.2, 4.1, 4.2, 6.1, and 7.1 mRNA. Kir4.2 protein was verified by immunocytochemistry and Western blotting. Kir4.2 mRNA in cultured cells was upregulated by hypoxia (hypoxia mimetic CoCl2 or 0.2% O2) and extracellular hyperosmolarity (addition of high NaCl or sucrose). Kir4.2 mRNA was suppressed by vascular endothelial growth factor (VEGF), blood serum, and thrombin whereas platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), and transforming growth factor-ß1 (TGF-ß1) increased it. Hyperosmotic Kir4.2 gene expression was mediated by TGF-ß1 receptor signaling while hypoxic gene transcription was dependent on PDGF receptor signaling. VEGF receptor-2 blockade increased Kir4.2 mRNA level under control, hyperosmotic, and hypoxic conditions. SiRNA-mediated knockdown of Kir4.2 decreased the cell viability and proliferation under control and hyperosmotic conditions. Kir4.2 channels play functional roles in maintaining the viability and proliferation of RPE cells. Downregulation of Kir4.2 by VEGF, via activation of VEGF receptor-2 and induction of blood-retinal barrier breakdown, may contribute to decreased viability of RPE cells under pathological conditions.


Assuntos
Células Epiteliais , Canais de Potássio Corretores do Fluxo de Internalização , Epitélio Pigmentado da Retina , Fator de Crescimento Transformador beta1 , Fator A de Crescimento do Endotélio Vascular , Hipóxia Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Regulação para Baixo , Células Epiteliais/metabolismo , Humanos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , RNA Mensageiro/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Epitélio Pigmentado da Retina/citologia , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
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
14.
PLoS One ; 17(6): e0269457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35671286

RESUMO

Little was known about the relationship between carrying mobile phone handsets by men and their risk perception of radiofrequency-electromagnetic field (RF-EMF) exposure due to carrying handsets close to the body. This study aimed to determine where men usually carried their handsets and to assess the relationship to risk perception of RF-EMF. Participants completed a self-administered questionnaire about mobile phone use, handset carrying locations, and levels of risk perception to RF-EMF. Data were analysed using linear regression models to examine if risk perception differed by mobile phone carrying location. The participants were 356 men, aged 18-72 years. They owned a mobile phone for 2-29 years, with over three quarters (78.7%) having a mobile phone for over 20 years. The most common locations that men kept their handsets when they were 'indoors' were: on a table/desk (54.0%) or in close contact with the body (34.7%). When outside, 54.0% of men kept the handset in the front trouser pocket. While making or receiving calls, 85.0% of men held their mobile phone handset against the head and 15.0% either used earphones or loudspeaker. Men who carried their handset in close contact with the body perceived higher risks from RF-EMF exposure compared to those who kept it away from the body (p<0.01). A substantial proportion of men carried their mobile phone handsets in close proximity to reproductive organs i.e. front pocket of trousers (46.5%). Men who kept their handset with the hand (p < .05), and those who placed it in the T-shirt pocket (p < .05), while the phone was not in use, were more likely to perceive health risks from their behaviour, compared to those who kept it away from the body. However, whether this indicates a causal relationship, remains open.


Assuntos
Telefone Celular , Estudos Transversais , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/análise , Humanos , Masculino , Percepção , Ondas de Rádio/efeitos adversos
15.
Exp Eye Res ; 219: 109038, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35305984

RESUMO

Alterations of the visual function during life are associated with changes in the morphological parameters of the outer retinal layers of the fovea. We evaluated age- and sex-related variations of the mean thicknesses of the different retinal layers at the central foveola which provides the maximal visual acuity. The vertical expansions of the following structures were measured on spectral-domain optical coherence tomographic images of 2944 healthy eyes of 1990 subjects with ages between 5 and 85 years: the total thickness of the retinal tissue, the thickness of the retinal pigment epithelium, the lengths of photoreceptors (receptor segments), photoreceptor outer segments (POS), and photoreceptor inner segments (PIS), and the thicknesses of the ellipsoid zone (EZ), myoid zone (MZ), external limiting membrane, outer nuclear layer, Henle fiber layer, and the horizontal layer of the Müller cell cone. We found diverse morphologies of the central photoreceptor layer with different thicknesses of the EZ and interdigitation zone lines. The mean total thickness of the retinal tissue at the central foveola showed three periods: it increased between 5 and about 41 years of age, displayed a plateau until about 52 years, and decreased continuously thereafter. Photoreceptors, POS, and PIS displayed their maximal mean lengths between 5 and about 36 years of age; the lengths decreased continuously between 36 and 85 years of age. Whereas the mean thickness of the EZ did not alter across the life span, the mean thickness of MZ displayed three periods: it increased between 5 and about 21 years of age, showed a plateau until about 36 years, and decreased considerably thereafter. Sex differences were observed for five parameters in eyes of subjects aging between 55 and 85 years. We suggest that the MZ thickness reflects the level of the metabolic activity of photoreceptors. The increase in the MZ thickness, likely reflecting increasing metabolic activity of photoreceptors, might contribute to the improvement of visual function in young subjects. The decrease of the MZ thickness in the fovea of elderly might reflect a decrease of the metabolic activity perhaps resulting from mitochondrial dysfunction which is known to occur in photoreceptors of aged eyes.


Assuntos
Fóvea Central , Retina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/anatomia & histologia , Epitélio Pigmentado da Retina , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Adulto Jovem
16.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1723-1731, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34605956

RESUMO

PURPOSE: To calculate the overall incidence of uveal melanoma in Germany and to compare incidences in different German states. In addition, we computed the overall and cancer-specific survival rates nationwide. METHODS: Incidence data for the period between 2009 and 2015, covering the entire German population, was collected through the German Center for Cancer Registry. ICD-O-3 topography codes C69.3-C69.4 and histology codes for melanoma subtypes were used to collect the incidence data. Confidence Intervals with a level of 95% (95% CI) were calculated for rates. Survival was calculated using the Kaplan-Meier. The log-rank test was used for survival comparisons. RESULTS: This study comprised 3654 patients with uveal melanomas, including 467 (12.8%) with iridial and ciliary body tumors. The overall age-standardized incidence rate (ASIR) was 6.41 person per million. Generally, the ASIR was higher in males than females (6.67 (95% CI 6.37-6.98) vs. 6.16 (95% CI 5.88-6.45 per million). Higher crude incidence rates were noted in the northeastern states (12.5 per million (95% CI 10.5-14.7) in Mecklenburg-Vorpommern) compared with the southwestern states (2.1 per million (95% CI 1.7-2.6) in Hessen). The 5-year overall survival stood at 47%, while the cancer-specific survival stood at 84%. Multivariate analysis showed that women, younger patients, and patients living in Berlin achieved significantly higher overall survival. CONCLUSION: Overall ASIR of uveal melanoma in Germany indicates that the disease is more common in males and that it follows the same geographical distribution previously noted in central European countries, with the highest incidence in northern parts of Germany.


Assuntos
Melanoma , Neoplasias Uveais , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Melanoma/epidemiologia , Taxa de Sobrevida , Neoplasias Uveais/epidemiologia
17.
Prog Retin Eye Res ; 86: 100977, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102317

RESUMO

Tractional deformations of the fovea mainly arise from an anomalous posterior vitreous detachment and contraction of epiretinal membranes, and also occur in eyes with cystoid macular edema or high myopia. Traction to the fovea may cause partial- and full-thickness macular defects. Partial-thickness defects are foveal pseudocysts, macular pseudoholes, and tractional, degenerative, and outer lamellar holes. The morphology of the foveal defects can be partly explained by the shape of Müller cells and the location of tissue layer interfaces of low mechanical stability. Because Müller cells and astrocytes provide the structural scaffold of the fovea, they are active players in mediating tractional alterations of the fovea, in protecting the fovea from such alterations, and in the regeneration of the foveal structure. Tractional and degenerative lamellar holes are characterized by a disruption of the Müller cell cone in the foveola. After detachment or disruption of the cone, Müller cells of the foveal walls support the structural stability of the foveal center. After tractional elevation of the inner layers of the foveal walls, possibly resulting in foveoschisis, Müller cells transmit tractional forces from the inner to the outer retina leading to central photoreceptor layer defects and a detachment of the neuroretina from the retinal pigment epithelium. This mechanism plays a role in the widening of outer lameller and full-thickness macular holes, and contributes to visual impairment in eyes with macular disorders caused by conractile epiretinal membranes. Müller cells of the foveal walls may seal holes in the outer fovea and mediate the regeneration of the fovea after closure of full-thickness holes. The latter is mediated by the formation of temporary glial scars whereas persistent glial scars impede regular foveal regeneration. Further research is required to improve our understanding of the roles of glial cells in the pathogenesis and healing of tractional macular disorders.


Assuntos
Células Ependimogliais , Tração , Astrócitos , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual
18.
Exp Eye Res ; 211: 108741, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34425102

RESUMO

Retinal pigment epithelial (RPE) cells express different subtypes of inwardly rectifying potassium (Kir) channels. We investigated whether human and rat RPE cells express genes of strongly rectifying Kir2 channels. We also determined the hypoxic and hyperosmotic regulation of Kir2.1 gene expression in cultured human RPE cells and the effects of siRNA-mediated knockdown of Kir2.1 on VEGFA expression, VEGF secretion, proliferation, and viability of the cells. Extracellular hyperosmolarity was induced by addition of NaCl or sucrose. Hypoxia and chemical hypoxia were produced by cell culture in 0.25% O2 and addition of CoCl2, respectively. Gene expression levels were evaluated by real-time RT-PCR. Rat RPE cells contained Kir2.1, Kir2.2, Kir2.3, and Kir2.4 gene transcripts while human RPE cells contained Kir2.1, Kir2.2, and Kir2.4 transcripts. Immunocytochemical data may suggest that Kir2.1 protein in cultured human cells is expressed in both perinuclear and plasma membranes. Kir2.1 gene expression and Kir2.1 protein level in human cells increased under hypoxic and hyperosmotic conditions. The expression of the Kir2.1 gene was mediated in part by diverse intracellular signal transduction pathways and transcription factor activities under both conditions; the hyperosmotic, but not the CoCl2-induced Kir2.1 gene expression was dependent on intracellular calcium signaling. Autocrine/paracrine activation of purinergic receptors contributed to Kir2.1 gene expression under hyperosmotic (P2Y1, P2Y2, P2X7) and CoCl2-induced conditions (P2Y2, P2X7). Exogenous VEGF, TGF-ß1, and blood serum decreased Kir2.1 gene expression. Inhibition of VEGF receptor-2 increased the Kir2.1 gene expression under control conditions and in CoCl2-simulated hypoxia, and decreased it under high NaCl conditions. Knockdown of Kir2.1 by siRNA inhibited the CoCl2-induced and hyperosmotic transcription of the VEGFA gene and caused a delayed decrease of the constitutive VEGFA gene expression while VEGF protein secretion was not altered. Kir2.1 knockdown stimulated RPE cell proliferation under control and hyperosmotic conditions without affecting cell viability. The data indicate that Kir2.1 channel activity is required for the expression of the VEGFA gene and inhibits the proliferation of RPE cells. Under control and hypoxic conditions, the extracellular VEGF level may regulate the production of VEGF via its inhibitory effect on the Kir2.1 gene transcription; this feedback loop may prevent overproduction of VEGF.


Assuntos
Regulação da Expressão Gênica/fisiologia , Soluções Hipertônicas/farmacologia , Hipóxia/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Epitélio Pigmentado da Retina/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Western Blotting , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Diabetes Mellitus Experimental , Retinopatia Diabética/metabolismo , Endotélio Vascular , Ensaio de Imunoadsorção Enzimática , Inativação Gênica , Masculino , Concentração Osmolar , RNA Interferente Pequeno/genética , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , Epitélio Pigmentado da Retina/metabolismo , Cloreto de Sódio/farmacologia , Sacarose/farmacologia
19.
Exp Eye Res ; 209: 108689, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34216615

RESUMO

Progressive retinal ganglion cell (RGC) loss underlies a number of retinal neurodegenerative disorders, which may lead to permanent vision loss. However, secreted neuroprotective factors, such as PEDF, VEGF and IL-6, which are produced by Müller cells, have been shown to promote RGC survival. Assuming that the communication of RGCs with Müller cells involves a release of glioactive substances we sought to determine whether retinal neurons are able to modulate expression levels of Müller cell-derived PEDF, VEGF and IL-6. We demonstrate elevated mRNA levels of these factors in Müller cells in co-cultures with RGCs or R28 cells when compared to homotypic Müller cell cultures. Furthermore, R28 cells were more protected from apoptosis when co-cultured with Müller cells. IL-6 and VEGF were upregulated in Müller cells under hypoxia. Both cytokines, as well as PEDF, induced an altered neuronal expression of members of the Bcl-2 family, which are central molecules in the regulation of apoptosis. These results suggest that in retinal ischemia, via own secreted mediators, RGCs can resist a potential demise by stimulating Müller cells to increase production of neuroprotective factors, which counteract RGC apoptosis.


Assuntos
Apoptose , Neuroproteção/fisiologia , Fármacos Neuroprotetores/farmacologia , Células Ganglionares da Retina/metabolismo , Neurônios Retinianos/metabolismo , Animais , Células Cultivadas , Ratos , Ratos Long-Evans , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/efeitos dos fármacos , Neurônios Retinianos/citologia , Neurônios Retinianos/efeitos dos fármacos
20.
PLoS One ; 16(7): e0253762, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34255777

RESUMO

Uncertainty is a crucial issue for any risk assessment. Consequently, it also poses crucial challenges for risk communications. Many guidebooks advise reporting uncertainties in risk assessments, expecting that the audience will appreciate this disclosure. However, the empirical evidence about the effects of uncertainty reporting is sparse and inconclusive. Therefore, based on examples of potential health risks of electromagnetic fields (EMF), three experiments were conducted analysing the effects of communicating uncertainties separately for hazard identification, risk characterisation and risk protection. The setups aimed to explore how reporting and how explaining of uncertainty affects dependent variables such as risk perception, perceived competence of the risk assessors, and trust in risk management. Each of the three experiments used a 2x2 design with a first factor presenting uncertainty descriptions (as used in public controversies on EMF related health effects) or describing a certainty conditions; and a second factor explaining the causes of uncertainties (by pointing at knowledge gaps) or not explaining them. The study results indicate that qualitative uncertainty descriptions regarding hazard identification reduce the confidence in the professional competencies of the assessors. In contrast, a quantitative uncertainty description in risk characterisation-regarding the magnitude of the risk-does not affect any of the dependent variables. Concerning risk protection, trust in exposure limit values is not affected by qualitative uncertainty information. However, the qualitative description of uncertainty regarding the adequacy of protection amplifies fears. Furthermore, explaining this uncertainty results in lower text understandability.


Assuntos
Comunicação , Campos Eletromagnéticos/efeitos adversos , Medição de Risco/normas , Humanos , Competência Profissional , Política Pública , Confiança , Incerteza
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