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1.
Br J Ophthalmol ; 94(5): 622-5, 2010 May.
Article in English | MEDLINE | ID: mdl-19726430

ABSTRACT

BACKGROUND/AIMS Skin autofluorescence (AF) is a non-invasive marker for advanced glycation endproducts (AGE) in tissues, making use of their characteristic AF pattern. The aim of this study was to investigate whether skin AF is increased in patients with neovascular age-related macular degeneration (AMD) compared with healthy controls. METHODS Skin AF was assessed in 73 consecutive patients with active and documented neovascular AMD without evidence for diabetic or hypertensive retinopathy and in 31 healthy age-matched controls. Exclusion criteria were: known renal disease, current inflammatory or malignant disease, or skin type V or VI. Skin AF was measured on the forearm and was calculated as a ratio of mean intensities detected from the skin between 420-600 and 300-420 nm. Student t test and chi(2) test were used to compare differences between groups. RESULTS Skin AF was increased in neovascular AMD compared with controls (2.57+/-0.68 vs 2.23+/-0.63 arbitrary units x 10(-2); p=0.018). In patients without vascular risk factors or cardiovascular disease, skin AF was not significantly higher than that of the controls. Skin AF correlated with age in both patients and controls. CONCLUSION Skin AF is increased in patients with neovascular AMD, suggesting that AMD is accompanied by enhanced systemic AGE accumulation, which may indicate a role in the pathophysiology of AMD.


Subject(s)
Macular Degeneration/metabolism , Skin/metabolism , Aged , Aged, 80 and over , Aging/metabolism , Case-Control Studies , Choroidal Neovascularization/metabolism , Cross-Sectional Studies , Female , Fluorescence , Glycation End Products, Advanced/metabolism , Humans , Male , Middle Aged
2.
Exp Eye Res ; 88(6): 1043-50, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19450456

ABSTRACT

The human vitreous body undergoes structural changes with aging. This can be followed by a posterior vitreous detachment, which can result in ocular pathology. As in many collagenous tissues, age-related changes in the vitreous could be caused by the formation of advanced glycation end products (AGEs). The goal of this study was to find out whether the AGE pentosidine accumulates in the human vitreous with aging. With this data we were able to estimate the half-life of vitreous collagen. Furthermore, we analyzed whether there was a gender difference in pentosidine accumulation, as this was seen in other tissues as well. Using high performance liquid chromatography, pentosidine contents were determined in whole vitreous bodies and in separate parts of vitreous bodies, which were all obtained from human donor eyes. Our results show that pentosidine accumulates in the human vitreous. From the rate of accumulation we could roughly estimate that vitreous collagen has as a similar or shorter half-life compared to skin collagen. This supports the concept of collagen turnover in the vitreous. In general, the female vitreous experiences a faster pentosidine accumulation than the male vitreous, and most of the pentosidine accumulation in the former occurs after 50 years of age.


Subject(s)
Aging/metabolism , Arginine/analogs & derivatives , Lysine/analogs & derivatives , Vitreous Body/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Arginine/metabolism , Child , Child, Preschool , Chromatography, High Pressure Liquid/methods , Ciliary Body/metabolism , Female , Glycation End Products, Advanced/metabolism , Humans , Lysine/metabolism , Male , Menopause/metabolism , Middle Aged , Sex Characteristics , Young Adult
4.
Biomaterials ; 27(32): 5554-60, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16872673

ABSTRACT

Cataract surgery is routinely performed to replace the clouded lens by a rigid polymeric intra-ocular lens unable to accommodate. By implanting a silicone gel into an intact capsular bag the accommodating properties of the natural lens can be maintained or enhanced. The implantation success of accommodating lenses is hampered by the occurrence of capsular opacification (PCO) due to lens epithelial cell (LEC) growth. In order to prevent LEC proliferation, a treatment regime using actinomycin D, cycloheximide and water was developed. The effectiveness of treatment was analyzed using an in vitro, MTT-based cell culture system and an ex vivo pig eye model in which the implanted lens-in-the-bag is cultured as a whole. LEC were exposed to treatment solutions for 5 min, then the cells were allowed to recover and to re-colonize the substratum. MTT conversion by cells was transiently inhibited by cycloheximide dissolved in water and by water alone. Exposure to actinomycin D resulted in a lasting inhibition of MTT conversion and consequently cell proliferation. These in vitro data could not be fully reproduced in the ex vivo pig eye model due to essential differences between both models. Treatment with actinomycin D containing solutions, however, resulted in a nearly complete absence of cells on the capsular wall. The pig eye model is a promising approach to further evaluate the effects of peri-surgical treatment during the accommodating intra-ocular lens implantation.


Subject(s)
Epithelial Cells/cytology , Lens Capsule, Crystalline/cytology , Lens Implantation, Intraocular/methods , Lenses, Intraocular , Animals , Cell Proliferation/drug effects , Cells, Cultured , Cycloheximide/toxicity , Dactinomycin/toxicity , Epithelial Cells/drug effects , Lens Capsule, Crystalline/drug effects , Rabbits , Swine
5.
Hum Gene Ther ; 17(6): 683-91, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16776576

ABSTRACT

Despite advances in revascularization techniques, limb salvage and relief of pain cannot be achieved in many diabetic patients with diffuse peripheral vascular disease. Our objective was to determine the effect of intramuscular administration of phVEGF165 (vascular endothelial growth factor gene-carrying plasmid) on critical limb ischemia (CLI) compared with placebo (0.9% NaCl). A double-blind, placebo-controlled study was performed in 54 adult diabetic patients with CLI. The primary end point was the amputation rate at 100 days. Secondary end points were a 15% increase in pressure indices (ankle-to-brachial index and toe-to-brachial index), clinical improvement (skin, pain, and Quality of Life score), and safety. In patients (n=27) treated with placebo versus phVEGF165-treated patients (n=27) the following results were found: 6 amputations versus 3 (p=not significant [NS]); hemodynamic improvement in 1 versus 7 (p=0.05); improvement in skin ulcers, 0 versus 7 (p=0.01); decrease in pain, 2 versus 5 (p=NS); and overall, 3 versus 14 responding patients (p=0.003). No grade 3 or 4 adverse effects were seen in these patients. We conclude that this small, randomized gene therapy study failed to meet the primary objective of significant amputation reduction. However, significant and meaningful improvement was found in patients treated with a VEGF165-containing plasmid. There were no substantial adverse events.


Subject(s)
Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 2/complications , Genetic Therapy , Ischemia/therapy , Peripheral Vascular Diseases/therapy , Vascular Endothelial Growth Factor A/genetics , Adult , Aged , Aged, 80 and over , Amputation, Surgical , Female , Humans , Injections, Intramuscular , Ischemia/etiology , Ischemia/surgery , Leg/blood supply , Middle Aged , Peripheral Vascular Diseases/etiology , Peripheral Vascular Diseases/surgery , Placebos/administration & dosage , Quality of Life , Skin Ulcer/etiology , Skin Ulcer/surgery , Skin Ulcer/therapy , Treatment Outcome , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor A/therapeutic use
6.
Graefes Arch Clin Exp Ophthalmol ; 243(7): 727-30, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15702328

ABSTRACT

PURPOSE: To report the treatment outcome of photodynamic therapy with verteporfin (PDT) for exudative retinal detachment associated with diffuse choroidal haemangioma in Sturge-Weber syndrome. METHODS: An interventional case report of a 12-year-old girl with Sturge-Weber syndrome who developed an exudative retinal detachment (visual acuity 20/400) that was treated with PDT under general anaesthesia. PDT was performed according to the standard (macular degeneration) protocol, using three nonoverlapping spots of 4,000 microm. RESULTS: Subretinal fluid resolved completely over a period of 5 months and visual acuity increased to 20/50. No side effects of the PDT treatment were encountered during 9 months' follow-up. CONCLUSION: In our patient PDT with verteporfin effectively resolved the exudative retinal detachment associated with a diffuse choroidal haemangioma. Resolution of subretinal fluid occurred over several months without retreatment. We noted no side effects of the combination PDT and general anaesthesia, nor did we encounter ocular side effects of the treatment.


Subject(s)
Anesthesia, General/methods , Choroid Neoplasms/drug therapy , Hemangioma/drug therapy , Photochemotherapy , Retinal Detachment/drug therapy , Sturge-Weber Syndrome/drug therapy , Child , Choroid Neoplasms/complications , Choroid Neoplasms/diagnostic imaging , Exudates and Transudates , Female , Hemangioma/complications , Hemangioma/diagnostic imaging , Humans , Photosensitizing Agents/therapeutic use , Porphyrins/therapeutic use , Sturge-Weber Syndrome/complications , Tomography, Optical Coherence , Treatment Outcome , Ultrasonography , Verteporfin
8.
Biomaterials ; 24(9): 1663-70, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12559826

ABSTRACT

The aim of this study is to determine rigid gas permeable (RGP) lens surface properties prior to and after wear that are influential on adhesion of Pseudomonas aeruginosa. After 10 and 50 days of wear and after end-stage use, lenses were collected for determination of physico-chemical surface properties and bacterial adhesion in a parallel plate flow chamber. Water contact angles on unused RGP lenses amounted 47+/-13 degrees and were affected by wear. In addition, %O at the lens surfaces, as determined by X-ray photoelectron spectroscopy increased after use for 10 and 50 days, but decreased after end-stage wear. The %N hardly increased after wear and, in line, SDS-PAGE did not indicate adsorbed proteins. The surface roughness of the lenses, as measured by atomic force microscopy amounted 9 nm after 10 and 50 days of use, but end-stage lenses were significantly rougher (48+/-23 nm). Moreover, initial deposition of P. aeruginosa #3 increased with increasing roughness for end-stage lenses. Multiple regression analysis, however, revealed that both physical and chemical surface properties were predictive for initial bacterial deposition to lens surfaces. After 10 days of wear, bacterial deposition was governed by the water contact angle, surface roughness, %O, %N, and %Si, while after 50 days of wear the surface roughness, %N, and %Si were found predictive for bacterial deposition. Initial bacterial deposition to end-stage lenses was solely dependent on the surface roughness. Summarizing, physico-chemical surface properties of RGP lenses change slightly during the first 10-50 days of wear, but end-stage lenses all had increased surface roughness, concurrent with increased bacterial adhesion.


Subject(s)
Bacterial Adhesion/physiology , Contact Lenses, Hydrophilic , Pseudomonas aeruginosa/physiology , Humans , Pseudomonas aeruginosa/isolation & purification , Regression Analysis
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