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Stadler S, Mohr A, Wagner A, Bäßler A, Fischer M, Putz FJ, Strack C, Li J, Arzt M. Weight loss induced alleviation of sleep-disordered breathing is associated with improvement of non-alcoholic fatty liver disease. Sleep Med 2023; 112:159-164. [PMID: 37866211 DOI: 10.1016/j.sleep.2023.10.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 10/04/2023] [Accepted: 10/16/2023] [Indexed: 10/24/2023]
Abstract
INTRODUCTION Sleep-disordered breathing (SDB) and non-alcoholic fatty liver disease (NAFLD) are both common comorbidities in obese patients. Structured weight loss programs are effective and can reduce the incidence and severity of obesity-related comorbidities. The objective of the present analysis is to test whether weight loss induced alleviation of SDB is a predictor for improvement of NAFLD. METHODS Obese participants underwent a standardized non-surgical 3 months weight reduction program (800 kilocalories per day with low carbohydrate and fat content). Abdominal sonography for NAFLD (grade 0 to 3) and monitoring for SDB (defined as apnea-hypopnea index [AHI] ≥ 15/h) were performed at baseline and after 3 months. Alleviation of SDB was defined as a shift from AHI≥ 15/h to <15/h. RESULTS 48 patients (48% female, age 42 ± 12 years, body-mass index 40.3 ± 8.1 kg/m2, AHI 14 ± 17/h, 85% NAFLD grade ≥1) participated in the weight loss program. In contrast to the no SDB group, in patients with SDB weight loss of 27.1 ±0 .9 kg (8.4 ± 2.8 kg/m2) after three months was paralleled by a reduction in AHI (-22 ± 17/h), prevalence of SDB (from 31% to 13%), and oxidized low-density lipoprotein (-13 ± 11 U/l). In individuals with preexisting SDB NAFLD grade improved more (2 versus 1, p<0.001) and was at a lower degree at 3 months than in those without SDB (0 versus 1, p = 0.015). In multivariable analysis models, SDB at baseline was associated with improvement of NAFLD grade (B 0.908; 95% CI 0.125, 1.691; p = 0.024), independently of age, sex, and BMI (each p>0.05, respectively). Decreasing BMI (B 0.16 [95%-CI 0.08; 0.23], p<0.001) and alleviation of SDB (B 0.90 [95%-CI 0.21; 1.58], p = 0.012) were independently associated with improvement of NAFLD grade. CONCLUSION Preexisting SDB and weight loss induced alleviation of SDB are predictors for improvement in NAFLD grade, independent of the extent of weight loss. SDB may contribute to the pathogenesis of NAFLD via SDB-induced oxidative stress and inflammation, but the causal mechanism remains unclear.
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Affiliation(s)
- S Stadler
- Department of Internal Medicine II, University Hospital Regensburg, Germany.
| | - A Mohr
- Department of Pneumology, Clinic Donaustauf, Germany
| | - A Wagner
- Department of Internal Medicine II, University Hospital Regensburg, Germany
| | - A Bäßler
- Department of Internal Medicine II, University Hospital Regensburg, Germany
| | - M Fischer
- Department of Internal Medicine II, University Hospital Regensburg, Germany; Department of Internal Medicine II, Clinic Kelheim, Germany
| | - F J Putz
- Department of Nephrology, University Hospital Regensburg, Germany
| | - C Strack
- Department of Internal Medicine II, University Hospital Regensburg, Germany
| | - J Li
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Germany
| | - M Arzt
- Department of Internal Medicine II, University Hospital Regensburg, Germany
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Al-Nawaiseh S, Krötz C, Rickmann A, Strack C, Germann A, von Briesen H, Szurman P, Schulz A, Stanzel BV. A rabbit model for outer retinal atrophy caused by surgical RPE removal. Graefes Arch Clin Exp Ophthalmol 2023; 261:2265-2280. [PMID: 36976356 PMCID: PMC10368565 DOI: 10.1007/s00417-023-06014-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 01/12/2023] [Accepted: 02/10/2023] [Indexed: 03/29/2023] Open
Abstract
PURPOSE We aimed to establish a rabbit model with retinal atrophy induced by an iatrogenic retinal pigment epithelium (RPE) removal, for future testing of the efficacy and safety of cell therapy strategies. METHODS A localized detachment of the retina from the RPE/choroid layer was created in 18 pigmented rabbits. The RPE was removed by scraping with a custom-made extendable loop instrument. The resulting RPE wound was observed over a time course of 12 weeks with optical coherence tomography and angiography. After 4 days (group 1) and 12 weeks (group 2), histology was done and staining with hematoxylin and eosin, as well as immunofluorescence performed to further investigate the effects of debridement on the RPE and the overlying retina. RESULTS Already after 4 days, we observed a closure of the RPE wound by proliferating RPE and microglia/macrophage cells forming a multilayered clump. This pattern continued over the observation time course of 12 weeks, whereby the inner and outer nuclear layer of the retina became atrophic. No neovascularization was observed in the angiograms or histology. The observed changes were limited to the site of the former RPE wound. CONCLUSIONS Localized surgical RPE removal induced an adjacent progressive retinal atrophy. Altering the natural course of this model may serve as a basis to test RPE cell therapeutics.
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Affiliation(s)
- Sami Al-Nawaiseh
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
| | - Christina Krötz
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | | | - Claudine Strack
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Anja Germann
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
| | - Peter Szurman
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany
| | - André Schulz
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany
| | - Boris V Stanzel
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany.
- Fraunhofer Institute for Biomedical Engineering, Sulzbach/Saar, Germany.
- Department of Ophthalmology, University of Bonn, Bonn, Germany.
- Klaus Heimann Eye Research Institute (KHERI), Sulzbach/Saar, Germany.
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Meyer JH, Marx J, Strack C, Holz FG, Schmitz-Valckenberg S. Imaging of Therapeutic Effects of Anti-Vascular Endothelial Growth Factor Inhibitors by Optical Coherence Tomography Angiography in a Rat Model. Transl Vis Sci Technol 2020; 9:29. [PMID: 32832234 PMCID: PMC7414645 DOI: 10.1167/tvst.9.7.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 04/24/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose The aim of the study was to investigate optical coherence tomography angiography (OCTA) as a high-resolution in vivo imaging modality for monitoring therapeutic response to different vascular endothelial growth factor inhibitors in the rat model of laser-induced choroidal neovascularization (CNV). Further, OCTA findings were compared with fluorescein angiography (FA) and fluorescence microscopy. Methods Laser treatment at day (D)0 was followed by intravitreal injection of aflibercept, AF564, and NaCl in dark agouti rats. Imaging with OCTA and FA was performed at D2, D7, D14, and D21. OCTA was compared to FA as well as confocal imaged flat mounts and analysis included quantification of CNV area, pixel intensity, vessel density, and number of vessel junctions. Results Within laser lesions, neovascularization were visible especially in deeper retinal layers on OCTA, but not on FA images. Using OCTA, mean CNV area (D21) at the level of the outer nuclear layer (ONL) was 0.017 mm² following aflibercept administration, 0.016 mm² following AF564 and 0.026 mm² following NaCl injection (P = 0.04 and P = 0.03). Similar differences between treatment groups were determined by FA and histology, although the overall CNV area was always larger on FA due to dye leakage (P ≤ 0.0001, all layers). Conclusions Compared to FA, OCTA imaging allows for a more precise and quantitative analysis of new blood vessel formation and therapeutic response to vascular endothelial growth factor (VEGF)-inhibitors, whereas it does not permit assessment of leakage. Translational Relevance These findings suggest that OCTA may be particularly useful for the investigation of new treatment targets in the animal model.
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Affiliation(s)
- Johanna H Meyer
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Janine Marx
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Claudine Strack
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Frank G Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Steffen Schmitz-Valckenberg
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA
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Schober AD, Strack C, Bauer S, Hubauer U, Schober AL, Uecer E, Maier LS, Luchner A, Jungbauer CG. P5453Cardiorenal biomarker N-acteyl-beta-D-glucosaminidase (NAG) potentially predicts mortality in chronic heart failure - A 10 year follow up. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
The strong relation between chronic heart failure (CHF) and chronic kidney disease (CKD) is well known as cardiorenal syndrome (CRS). The current study focused on the impact of novel markers of kidney injury next to the established cardiac marker NT-proBNP as predictors for mortality in patients with CHF in a long term follow up.
Methods
We conducted a prospective longitudinal study. The novel renal biomarkers kidney injury molecule-1 (KIM-1), N-acteyl-β-D-glucosaminidase (NAG) and Neutrophil Gelatinase-Associated Lipocalin (NGAL) were assessed from urine samples. Additionally, blood levels of NT-proBNP were determined. The primary endpoint all-cause mortality was evaluated after a median follow-up of 104 months (interquartile range 42–117 months).
Results
149 adolescents (mean age 62±12 years) with CHF (mean ejection fraction 32±9%) were enrolled. 79 (53%) patients died. The secondary endpoint was reached by 104 patients (70%).
The renal marker NAG (HR 1.02, p=0.002) was a significant and independent predictor for all-cause mortality next to the established cardiac biomarker NTproBNP (HR 1.0, p<0,001) using Cox regression analysis, opposite to KIM-1 as well as NGAL (each p=n.s.). Similar results were obtained for the combined endpoint of all-cause mortality and hospitalization for heart failure.
In a multivariate analysis model with biomarkers and clinical parameters NAG (HR 1.02, p=0.036) remained a significant predictor for all-cause mortality next to NT-proBNP (HR 1.0, p=0.027, older age (HR 1.04, p=0.004), the lack of diabetes mellitus (HR 0.39, p<0.001), reduced EF (HR 0.97, p=0.034) and creatinine (HR 1.45, p=0.026). Again similar results were obtained for the secondary endpoint.
Patients were stratified into groups with markers above and below Youden Index to calculate Kaplan-Meier analysis. A combined analysis of NT-proBNP (< and ≥1906 pg/mL) and NAG (< and ≥10 U/gUCr) revealed an increase of the predictive value of each marker: patients with all three markers above Youden index had the highest mortality rate (79%) compared to patients with one (43%) or none (26%) marker above Youden Index.
All-cause Mortality
Conclusion
The current 10-years long-term follow-up suggests that the tubular biomarker NAG as cardiorenal biomarker in combination with NT-proBNP may allow to discriminate a high-risk collective of chronic heart failure patients. These findings emphasize the close relationship of kidney injury and renal function in patients with CHF.
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Affiliation(s)
- A D Schober
- University Hospital Regensburg, Regensburg, Germany
| | - C Strack
- University Hospital Regensburg, Regensburg, Germany
| | - S Bauer
- University Hospital Regensburg, Regensburg, Germany
| | - U Hubauer
- University Hospital Regensburg, Regensburg, Germany
| | - A L Schober
- University Hospital Regensburg, Regensburg, Germany
| | - E Uecer
- University Hospital Regensburg, Regensburg, Germany
| | - L S Maier
- University Hospital Regensburg, Regensburg, Germany
| | - A Luchner
- Hospital Barmherzige Bruder, Cardiology, Regensburg, Germany
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Meyer JH, Larsen PP, Strack C, Harmening WM, Krohne TU, Holz FG, Schmitz-Valckenberg S. Optical coherence tomography angiography (OCT-A) in an animal model of laser-induced choroidal neovascularization. Exp Eye Res 2019; 184:162-171. [PMID: 31002822 DOI: 10.1016/j.exer.2019.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 03/18/2019] [Accepted: 04/04/2019] [Indexed: 12/17/2022]
Abstract
Aim of the study was to compare optical coherence tomography angiography (OCT-A) and conventional fluorescein angiography (FA) for quantitative analysis of the retinal and choroidal vasculature in the animal model of laser-induced choroidal neovascularization (CNV). Therefore, Dark Agouti rats underwent argon laser photocoagulation to induce CNV at D0. In vivo imaging using combined confocal scanner laser ophthalmoscopy (cSLO)-based FA and OCT-A (Heidelberg Engineering GmbH, Heidelberg, Germany) was performed before and immediately after laser treatment as well as at day 2, 7, 14 and 21. OCT-A en-face images were compared to cSLO images obtained by conventional FA topographic uptake recorded using a series of different pre-defined focus settings. For a quantitative comparison of CNV imaging by OCT-A and FA, CNV area, vessel density, number of vessel junctions, total vessel length and number of vessel end points were analyzed. Subsequent ex vivo analyses of the CNV included immunofluorescence staining of vessels in retinal and RPE/choroidal/scleral flatmount preparations. We found, that OCT-A allowed for high-resolution non-invasive imaging of the superficial, intermediate and deep retinal capillary plexus as well as the choroidal blood vessels in rats. Compared with OCT-A, visualization of CNV progression by invasive FA was less accurate, in particular the deep vascular plexus was visualized in more detail by OCT-A. The area of neovascularization was mainly detected in the deep retinal vascular plexus, outer nuclear layer (ONL), ellipsoid zone (EZ) and the choroid. Within the laser lesions, signs of CNV formation occurred at day 7 with progression in size and number of small vessels until day 21. Due to leakage and staining effects, CNV areas appeared significantly larger in FA compared to OCT-A images (p ≤ 0.0001 for all tested layers). Vessel density, number of vessel junctions, total vessel length and number of vessel end points were significantly higher in intermediate vascular plexus (IVP) and deep vascular plexus (DVP) in OCT-A compared to FA images. Overall, CNV area in flatmounts was similar to OCT-A results and much smaller compared to the area of dye leakage by FA. This study demonstrates that in vivo OCT-A imaging in small animals is feasible and allows for precise analysis of the formation of new blood vessel formation in the animal model of laser-induced CNV. Given its superior axial resolution, sensitivity and non-invasiveness compared to conventional FA imaging, OCT-A opens the door for a more detailed evaluation of CNV development in such a model and, thus, enables the analysis of the response to novel therapeutic interventions in longitudinal in vivo studies.
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Affiliation(s)
- Johanna H Meyer
- Department of Ophthalmology, University of Bonn, Bonn, Germany.
| | - Petra P Larsen
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Claudine Strack
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | | | - Tim U Krohne
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Frank G Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany
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Zeller J, Krueger C, Lamounier-Zepter V, Fenk S, Strack C, Mohr M, Loew T, Schmitz G, Maier L, Fischer M, Baessler A. 108The adipo-fibrokine Activin A is associated with metabolic abnormalities and left ventricular diastolic dysfunction. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy564.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- J Zeller
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - C Krueger
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | | | - S Fenk
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - C Strack
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - M Mohr
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - T Loew
- University Hospital Regensburg, Department of Psychosomatics, Regensburg, Germany
| | - G Schmitz
- University Hospital Regensburg, Central Institute for Clinical Chemistry and Laboratory Medicine, Regensburg, Germany
| | - L Maier
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - M Fischer
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
| | - A Baessler
- University Hospital Regensburg, Internal Medicine II, Regensburg, Germany
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Fenk S, Mueller S, Wallner S, Strack C, Hubauer U, Mohr M, Zeller J, Rehli M, Loew T, Maier LS, Fischer M, Baessler A. 111The cardiometabolic consequences of obesity susceptibility gene variants in severe obesity. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy564.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- S Fenk
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - S Mueller
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - S Wallner
- University Hospital Regensburg, Institute of Clinical Chemistry and Laboratory Medicine, Regensburg, Germany
| | - C Strack
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - U Hubauer
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - M Mohr
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - J Zeller
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - M Rehli
- University Hospital Regensburg, Department of Internal Medicine III, Regensburg, Germany
| | - T Loew
- University Hospital Regensburg, Department of Psychosomatic Medicine, Regensburg, Germany
| | - L S Maier
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - M Fischer
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - A Baessler
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
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Mohr M, Zeller J, Fenk S, Strack C, Loew T, Maier LS, Fischer M, Baessler A. 5218Epicardial adipose tissue is related to left ventricular diastolic dysfunction in healthy obese and metabolic syndrome obese. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.5218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- M Mohr
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - J Zeller
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - S Fenk
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - C Strack
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - T Loew
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - L S Maier
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - M Fischer
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
| | - A Baessler
- University of Regensburg, Department of Internal Medicine II, Regensburg, Germany
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Herwig-Carl MC, Sharma A, Moulin A, Strack C, Loeffler KU. BAP1 Immunostaining in Uveal Melanoma: Potentials and Pitfalls. Ocul Oncol Pathol 2018; 4:297. [PMID: 30320100 DOI: 10.1159/000486370] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 12/11/2017] [Indexed: 11/19/2022] Open
Affiliation(s)
- Martina C Herwig-Carl
- Division of Ophthalmic Pathology, Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Amit Sharma
- Division of Ophthalmic Pathology, Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Alexandre Moulin
- Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland
| | - Claudine Strack
- Division of Ophthalmic Pathology, Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Karin U Loeffler
- Division of Ophthalmic Pathology, Department of Ophthalmology, University of Bonn, Bonn, Germany
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Al-Nawaiseh S, Thieltges F, Liu Z, Strack C, Brinken R, Braun N, Wolschendorf M, Maminishkis A, Eter N, Stanzel BV. A Step by Step Protocol for Subretinal Surgery in Rabbits. J Vis Exp 2016. [PMID: 27684952 PMCID: PMC5092014 DOI: 10.3791/53927] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models.
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Affiliation(s)
| | | | - Zengping Liu
- Department of Ophthalmology, University of Bonn; Department of Ophthalmology, National University of Singapore
| | | | | | | | | | - Arvydas Maminishkis
- Section on Epithelial and Retinal Physiology and Disease, National Eye Institute/National Institutes of Health
| | - Nicole Eter
- Department of Ophthalmology, University of Münster
| | - Boris V Stanzel
- Department of Ophthalmology, University of Bonn; Surgical Retina Department, Singapore National Eye Centre;
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Laser H, Hockwin O, Müller-Breitenkamp U, Dobbs R, Bates S, Strack C. Risk factor diabetes: long-term follow-up Scheimpflug slit image analysis of lens transparency of diabetic patients. Dev Ophthalmol 2015; 21:70-7. [PMID: 1868953 DOI: 10.1159/000419938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- H Laser
- Department of Experimental Ophthalmology, University of Bonn, FRG
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Strack C, Fessmann D, Fenk S, Waldmann K, Kempinger S, Loew T, Riegger G, Schmitz G, Fischer M, Baessler A. QT prolongation is frequently observed in obesity with and without the metabolic syndrome and can be reversed by long term weight reduction. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p4287] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Fenk S, Baessler A, Rousseva E, Strack C, Manka M, Schmitz G, Riegger G, Loew T, Lahmann C, Fischer M. Successful long-term weight reduction improves left ventricular diastolic function and physical performance in severe obesity. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht307.p730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Strack C. ML03 WORK INJURIES ? NOT ALWAYS WHAT THEY SEEM. ANZ J Surg 2007. [DOI: 10.1111/j.1445-2197.2007.04123_3.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Some years ago, Nidek developed a new imaging system for the anterior eye segment, which offers the possibility of recording Scheimpflug and retroillumination images. The system consists of 2 different technical units, a camera unit for image recording and a computer unit for storage, system operation and image analysis. To evaluate the clinical use of the system and its reproducibility, a study with 31 volunteers/patients was performed that were photographed with the Nidek EAS 1000 at the meridians 0 degree, 45 degrees and 180 degrees. Two examinations with a 1-week interval were performed. In addition, a direct comparison of the EAS 1000 with the Topcon SL-45 was carried out with 32 volunteers that were photographed at 0 degree and 45 degrees; a retroillumination photo was additionally recorded. The video images were evaluated with the computer software, the SL-45 negatives were standardly measured with a Joyce-Loebl densitometer. The handling of the EAS 1000 in clinical use was found to be easy and comfortable for the patient, as the alignment is done with infrared light. Difficulties occur only with the retroillumination photography in that the infrared light for imaging may outshine the red fixation light during exposure. However, shadowing problems due to the eyelashes occur in oblique slit positions, especially in those patients with a pronounced front head. In studying the reproducibility, the mean values of the individual coefficients of variation for light scattering (density) were in a range between 3.6 and 5.06%, but more than 35% of the single values show a variation coefficient above 5% (maximum 20.3%).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A Wegener
- Department of Experimental Ophthalmology, University of Bonn, FRG
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Abstract
Decompression sickness (DCS) is usually categorised as type I (mild; peripheral pain, non-neurological) or type II (serious; neurological). Type II is regarded as predominantly a spinal cord disease with infrequent cerebral involvement. Cerebral perfusion was studied by injection of 99Tcm-hexamethylpropyleneamine oxime and single photon emission tomography in 28 divers with confirmed incidents of DCS and cerebral arterial gas embolism (CAGE). Cerebral perfusion deficits were present in all 23 cases of type II DCS and in all 4 cases of CAGE. No deficits were present in the single case of type I DCS. Type II DCS should be recognised as a diffuse, multifocal, central nervous system disease.
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