0000000000261600

AUTHOR

Albert J. Augustin

Oxidative tissue damage after phacoemulsification: influence of ophthalmic viscosurgical devices.

To quantify the oxidative tissue damage after phacoemulsification, correlate the damage to the energy applied, and investigate the influence of ophthalmic viscosurgical devices (OVDs).Department of Ophthalmology, University of Mainz, Mainz, Germany.The study comprised 130 eyes operated on by 1 surgeon using the same phacoemulsification machine. Some eyes received an OVD before phacoemulsification and some did not. Energy values were expressed as phaco time; that is, ultrasound (US) time (seconds) after conversion to 100% phaco power. Patients were grouped as follows: Group 1, phaco time less than 20 seconds and no OVD; Group 2, phaco time 20 to 40 seconds and no OVD; Group 3, phaco time mor…

research product

Allopurinol has Immunomodulating Activity following Topical and Systemic Application in Experimental Autoimmune Uveitis

PurposeAllopurinol has beneficial effects in the systemic treatment of lens-induced uveitis and experimental autoimmune uveitis (EAU). This is believed to be due to a reduction of oxidative tissue damage through its dose-dependent free radical scavenging ability, and to an immunomodulating effect. The purpose of this study was to demonstrate the immunological effects on the IgG-antibody repertoire in EAU after topical and systemic allopurinol and steroids.MethodsWe assigned 43 male Lewis rats to 6 different groups: healthy rats (BASE, n=3), EAU without therapy (CTRL, n=9); systemic treatment with allopurinol (ALSYS, n=9, 50 mg/kg body wt.i.v., given every three days for two weeks), topical …

research product

Topical allopurinol or corticosteroids and acetylcysteine in the early treatment of experimental corneal alkali burns: a pilot study.

PURPOSE. To investigate the effect of topical allopurinol on experimental corneal burns and to compare this to established treatment modalities such as topical prednisolone and acetylcysteine. METHODS. Twenty Wistar rats were randomly assigned to four groups (n=5 each). The groups were controls (normal saline), allopurinol 0.4% eye drops, prednisolone acetate 1% eye drops and acetylcysteine 8% eyedrops. Corneal burn was induced using a 3 mm paper disc soaked in 1N NaOH for 60 seconds. Drops were instilled 6 times per day. In addition, one drop/day ofloxacine was given to prevent secondary infections. Eyes were enucleated 50 hours later and fixed in 4.5% formaldehyde. Three histological leve…

research product

Analysis of tear protein patterns by a neural network as a diagnostical tool for the detection of dry eyes

The electrophoretic patterns of tears from patients with dry-eye disease (n = 43) and from healthy subjects (n = 17) were analyzed by means of multivariate statistical methods and an artificial neural network (ANN), following sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). From each electrophoretic pattern a data set was created, randomly divided into test (unknown samples) and training patterns (known samples), with ANN training by one of these sets. After training, the performance of the ANN was checked by presenting the test data set to the ANN. Furthermore, the data was classified using multivariate analysis of discriminance. The groups were significantly different…

research product

Abstract of the 68th Meeting (Spring Meeting) 6–9 March 1990, Heidelberg

research product

Immunological Effects of Allopurinol in the Treatment of Experimental Autoimmune Uveitis (EAU) after Onset of the Disease

Purpose Allopurinol reduces oxidative tissue damage and exerts immunomodulating effects in the treatment of experimental autoimmune uveitis (EAU). However, the mechanism of the immunologic pathway remains unclear. In previous studies, treatment was started at the time of immunization. Therefore, whether allopurinol prevents the onset of the disease (i.e., acts in a protective manner) is not known. Methods Sixteen male Lewis rats were used: 6 EAU without therapy [control]; 4 EAU with allopurinol treatment starting 7 days after immunization [AL7]; and 6 EAU with allopurinol treatment starting 11 days after immunization [AL11]. Their sera were tested against Western blots of sodium dodecyl sul…

research product

Healon5 viscoadaptive formulation: Comparison to Healon and Healon GV

Abstract Purpose To compare the rheological characteristics of a viscoadaptive viscoelastic formulation with those of 2 standard ophthalmic viscosurgical devices (OVDs). Setting Department of Ophthalmology, Johannes Gutenberg-University, and Max Planck-Institute for Polymer Research, Mainz, Germany. Methods An independent comparative study of 3 OVDs of sodium hyaluronate (Healon®, Healon GV®, and Healon®5) was performed using the Advanced Rheometric Expansion System to analyze rheologic behavior (eg, dynamic frequency dependence of the complex viscosity) as well as rheological parameters (eg, viscosity at zero shear rate, pseudoplasticity, relaxation time, elastic and viscous modulus). Resu…

research product

Analysis of Tear Protein Patterns for the Diagnosis of Dry Eye

Dry eye syndrome occurs very frequently in the industrial world. In the United States, one of five people, 59 millions patients, suffer from symptoms of this disease (Eagle Vision, Yankelovich and Partners, 1997), and the number of patients has doubled in the last 10 years. 1-4 Diagnosis and treatment of dry eye syndrome are challenging. In fact, a curative therapy of this disease does not exist. Dry eye is a disease with various symptoms resulting from aqueous, mucin or lipid deficiency. Different diseases, among them Sjogren’s syndrome, can cause this deficiency, but most patients do not have accompanying disorders.

research product

Physicochemical Surface Properties of Various Intraocular Lenses

<i>Purpose:</i> It is of major interest to understand how intraocular lens (IOL) surfaces interact with aqueous humor or tissues after implantation. Important parameters to describe the physicochemical surface properties are the contact angle and critical surface tension. Therefore, we performed measurements of the contact angle and critical surface tension of several commercially available IOLs. <i>Setting:</i> Department of Ophthalmology, Johannes Gutenberg University, Mainz, University Eye Hospital, Tübingen, and Max Planck Institute for Polymer Research, Mainz, Germany. <i>Methods:</i> A total of 17 commercially available standard quality IOL types (6…

research product

Endotoxins in ophthalmic viscosurgical devices.

Purpose To measure the endotoxin concentration (EC) of 25 commercially available, hyaluronic acid- and hydroxypropylmethylcellulose-based (HPMC) ophthalmic viscosurgical devices (OVDs). Methods The in vitro Limulus amebocyte lysate (LAL) assay, which indicates the presence of endotoxins originating from gram-negative bacteria, was used to determine the EC. The procedure was performed according to the European Pharmacopoeia/USP. EC including duplicate determinations, negative controls, dilution series with control standard endotoxin, dilution series with sample extract and positive sample control. Results 16 OVDs (Amvisc®, Amvisc® Plus, Biolon®, Coatel®, Healon®, Healon® GV, Healon®5, HPMC O…

research product

Solvent for removing silicone oil from intraocular lenses: experimental study comparing various biomaterials.

Abstract Purpose To evaluate the effectiveness of a perfluorocarbon—perfluorohexyloctane (PFHO)—in removing silicone oil from different intraocular lenses (IOLs) and determine whether any removal technique enhances the removal of silicone oil. Methods Six IOL materials were analyzed: standard poly(methyl methacrylate) (PMMA), heparin-surface-modified (HSM) PMMA, AcrySof, 2 polyHEMAs with different water contents, and a second-generation SLM-2 silicone. One or 2 μL of a highly viscous silicone oil (5700 cs) was applied to the center of each IOL optic. Perfluorohexyloctane (2 mL) was then used to remove the silicone oil by 1 of 3 techniques: immersion of the IOL in PFHO; irrigation of the sil…

research product

Retina Summit Karlsruhe 2009

During the this year´s Retina Summit Karlsruhe, an international expert faculty of 20 highly renowned retina specialists and more than 300 participants found their way to Karlsruhe to share their knowledge of the latest trends in surgical technology and pharmacology. After an angiography course on Friday, the 1-day symposium of almost 40 short lectures covered recent developments in age-related macular degeneration and diabetic macular edema, and the implications and challenges associated with microincision vitrectomy surgery, new devices and advances in imaging technologies.

research product

Osmolality of various viscoelastic substances: comparative study.

Abstract Purpose To determine the osmolality of various viscoelastic substances. Setting Department of Ophthalmology, Johannes Gutenberg-University, Mainz, and Institute for Medical Device Testing, Memmingen, Germany. Methods The analysis was carried out according to the European Pharmacopoeia by means of a calibrated osmometer using the freezing-point depression method. Each syringe was analyzed as a duplicate analysis. Results Mean osmolalities (mOsmol/kg) of the sodium hyaluronate viscoelastic substances were Allervisc® 299; Allervisc® Plus 307; Amvisc® Plus 335; AMO Vitrax® 284; Biolon® 279; Dispasan® 311; Dispasan® Plus 314; Healon® 295; Healon GV® 312; Healon®5 322; HYA-Ophtal® 376; M…

research product

Two-dimensional analysis of tear protein patterns of diabetic patients

In diabetic patients, dry eye and other ocular surface diseases occur more often than in healthy subjects. The aim of this study was to analyze the tear protein patterns of patients suffering from diabetes mellitus type II (dia) and to compare them to the patterns of healthy volunteers (ctrl). Tear proteins of nonstimulated tears of 20 patients (ctrl n=10, dia n=10) were separated using two-dimensional electrophoretic techniques. The protein patterns of each group were analyzed by a multivariate analysis of discriminance. Furthermore, for all spots of each gel, a 50 x 50 variables pH/Mr (molecular weight) array was generated and subsequently analyzed by a multivariate analysis of discrimina…

research product

CHANGES IN THE TEAR PROTEIN PATTERNS OF DIABETIC PATIENTS USING TWO-DIMENSIONAL ELECTROPHORESIS.

Four to five million Germans suffer from diabetes mellitus, and worldwide there are about 100 million people that suffer with the disease. In diabetic patients, dry eye and other ocular surface diseases occur more often than in healthy subjects. Very little is known about the alterations in tears caused by diabetes mellitus, or its influence on the pathogenesis of e.g., the dry eye disease. Recent studies from our group showed that there are differences in the one-dimensional electrophoretic tear protein separations between diabetic patients and healthy volunteers.1,2 The aim of this study is to analyze the tear protein patterns of patients suffering from diabetes (DIA) (Fig.l), and to comp…

research product

Changes in the Tear Protein Patterns of Diabetic Patients Using Two-Dimensional Electrophoresis

Four to five million Germans suffer from diabetes mellitus, and worldwide there are about 100 million people that suffer with the disease. In diabetic patients, dry eye and other ocular surface diseases occur more often than in healthy subjects. Very little is known about the alterations in tears caused by diabetes mellitus, or its influence on the pathogenesis of e.g., the dry eye disease. Recent studies from our group showed that there are differences in the one-dimensional electrophoretic tear protein separations between diabetic patients and healthy volunteers.1,2 The aim of this study is to analyze the tear protein patterns of patients suffering from diabetes (DIA) (Fig.l), and to comp…

research product

Analysis of tear proteins by one- and two-dimensional thin-layer iosoelectric focusing, sodium dodecyl sulfate electrophoresis and lectin blotting. Detection of a new component: cystatin C.

· Background: Isoelectric focusing (IEF) of tear proteins has not yet been carried out in a satisfactory way. Two-dimensional (2D) electrophoresis, especially in the combination of IEF with SDS, is able to differentiate between proteins in detail. The purpose of this study was therefore to analyze tear proteins by 1D IEF alone and in combination with a 2D pattern, and by IEF followed by lectin staining. · Methods: Ampholines, covering a broad range from pH 3 to pH 10, were applied. After IEF, semi-dry blotting and incubation with a group II lectin and two group V lectins was performed. · Results: Tear proteins could be separated into 31 single bands. Tear-specific pre-albumin (TSPA), lactof…

research product