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Age, gender, IOP, refraction and optic disc topography in normal eyes. A cross-sectional study using raster and scanning laser tomography

Purpose: To study the influeuce of age, gender, intraocular pressure and refraction on optic disc topography in normal subjects. Methods: We studied both eyes of 225 healthy subjects between 20 and 80 years of age using raster tomography (Glaucoma-Scope®, Ophthalmic Imaging Systems, Sacramento CA, USA) and scanning laser tomography (Heidelberg Engineering, Heidelberg, Germany). We chose to study c

A comparison of dorzolamide and timolol in patients with pseudoexfoliation and glaucoma or ocular hypertension

Purpose: The purpose of the study is to compare the efficacy and safety profile of 2.0% dorzolamide (three times daily) and 0.5% timolol (twice daily) for up to 6 months in patients with glaucoma or ocular hypertension associated with pseudoexfoliation. The additive effects of dorzolamide and timolol in patients requiring add-on therapy also was evaluated. Methods: This was a double-masked, random

Prevalence of diabetic retinopathy in relation to age at onset of the diabetes, treatment, duration and glycemic control

To study the frequency of diabetic retinopathy in relation to age at diagnosis, treatment, duration of diabetes and glycemic control as measured by means of HbA(1c) levels, we performed a cross-sectional, register-based study in the Helsingborg area of southern Sweden, comprising 2232 diabetic patients. Of the known diabetic population < 75 years old, approximately 70% were estimated to be include

Progression of retinopathy is related to glycaemic control even in patients with mild diabetes mellitus

To study the progression of retinopathy in patients with mild diabetes mellitus, we examined, in a cohort study, 347 patients treated with diet alone at baseline. The patients participated in an ophthalmological screening and control programme, and diet-treated patients who were examined between January 1990 and July 1992 were included in the study and followed until October 1995. Mean follow-up t

Incidence of blindness and visual impairment in diabetic patients participating in an ophthalmological control and screening programme

We studied the incidence of blindness and visual impairment in patients who were enrolled in a photographic control- and screening program for diabetic retinopathy. The study cohort consisted of 2133 patients examined between January 1990 and December 1992 and followed until October 1st 1995. The occurrence of blindness (visual acuity ≤ 0.1) and moderate visual impairment (visual acuity 0.2-0.4) w

Sensitivity and specificity of structural optic disc parameters in chronic glaucoma

We studied different structural optic disc parameters and their ability to discriminate between normal and glaucoma eyes using computerized raster tomography. Two hundred and seventy-six eyes of 138 normal subjects and 146 eyes of 102 glaucoma patients were examined with a raster tomographic imaging system (The Glaucoma-Scope®, Ophthalmic Imaging Systems, Sacramento, CA). Glaucoma eyes were classi

Pitfalls of automated perimetry in glaucoma diagnosis

Perimetry is a cornerstone in glaucoma management. The detection of glaucomatous visual field loss is of crucial importance for diagnosing the disease. Automated threshold perimetry makes thorough testing of the central visual field very possible and high-quality data are often achieved. Certain factors, however, may hamper the visual field examination or visual field interpretation. Many diseases

Diffuse visual field loss and glaucoma

Abstract. It is often claimed that general reduction, or diffuse loss, of perimetric sensitivity is an early sign of glaucoma. Our clinical experience and the results of a few other studies led us to believe otherwise. To investigate factors associated with diffuse field loss we reviewed 4222 Humphrey 30–2 threshold tests from 1582 eyes of 862 patients followed at our department. Most of these pat

Latanoprost administered once daily caused a maintained reduction of intraocular pressure in glaucoma patients treated concomitantly with timolol

The long term effects of two dose regimens of latanoprost (PhXA41) administered to eyes concomitantly treated with timolol which had not adequately been controlled by timolol alone were compared. A total of 50 patients, 17 with primary open angle glaucoma and 33 with capsular glaucoma, were recruited from five clinics. All had glaucomatous visual field defects and an intraocular pressure (IOP) of

Shape Synthesis Based on Topology Sensitivity

A method evaluating the sensitivity of a given parameter to topological changes is proposed within the method of moments paradigm. The basis functions are used as degrees of freedom which, when compared to the classical pixeling technique, provide important advantages, one of them being impedance matrix inversion free evaluation of the sensitivity. The devised procedure utilizes port modes and the

Stress induced biofilm formation in Propionibacterium acidipropionici and use in propionic acid production.

Propionibacterium acidipropionici produces propionic acid from different sugars and glycerol; the production can be improved by high cell density fermentations using immobilized cells that help to overcome the limitations of the non-productive lag phase and product inhibition. In this study, the use of stress factors to induce P. acidipropionici to form biofilm and its use as an immobilization pro

Response surface methodology and artificial neural network modeling of an aqueous two-phase system for purification of a recombinant alkaline active xylanase

A two-stage polyethylene glycol (PEG)-phosphate aqueous two-phase system was used for purification of a highly thermostable and alkaline active recombinant xylanase. Response surface methodology (RSM) and artificial neural network (ANN) have been used to develop predictive models for simulation and optimization of purification process. Effects of pH, PEG molecular weight, concentrations of phospha

Chemical relationships of ambers using attenuated total reflectance Fourier transform infrared spectroscopy

Amber is known for its remarkably well-preserved fossils, but the chemical complexity of amber and its history are less well known. Amber is highly variable in both its physical and chemical properties, which are dependent on factors such as the source tree and the diagenetic history. Amber from a given locality therefore has a unique chemical composition. Fourier transform infrared (FTIR) spectro

Small angle neutron scattering of native and reconstituted silk fibroin

Silks spun by spiders and insects are independently evolved proteinaceous biomaterials with fascinating physical properties attracting scientists from a wide range of disciplines using a wide range of analytical tools. Here we demonstrate the suitability of neutron small angle scattering (SANS) to investigate the morphology and structure of native silk fibroin at near in vivo conditions. Comparing

Structural disorder in silk proteins reveals the emergence of elastomericity

Spider silks combine basic amino acids into strong and versatile fibers where the quality of the elastomer is attributed to the interaction of highly adapted protein motifs with a complex spinning process. The evaluation, however, of the interaction has remained elusive. Here, we present a novel analysis to study silk formation by examining the secondary structures of silk proteins in solution. Us

Conformational polymorphism, stability and aggregation in spider dragline silks proteins

Spider silk is spun in a complex and unique process, thought to depend on a hydrophobic conversion of a predominantly disordered to a β-sheet rich protein structures. To test this hypothesis we monitored the effect of cationic (DOTAC) and anionic (alkyl sulfate) detergents and of (ii) solvent polarity using a series of alcohols on the secondary structure transition in dilute solutions of native sp

Secondary structures and conformational changes in flagelliform, cylindrical, major, and minor ampullate silk proteins. Temperature and concentration effects

Orb weaver spiders use exceptionally complex spinning processes to transform soluble silk proteins into solid fibers with specific functions and mechanical properties. In this study, to understand the nature of this transformation we investigated the structural changes of the soluble silk proteins from the major ampullate gland (web radial threads and spider safety line); flagelliform gland (web s

Transition to a β-sheet-rich structure in spidroin in vitro : The effects of pH and cations

Unlike man-made fibers, the silks of spiders are spun from aqueous solutions and at atmospheric pressure in a process still poorly understood. The molecular mechanism of this process involves the conversion of a highly concentrated, predominantly disordered silk protein (spidroin) into β-sheet-rich structures. To help store and transport the spidroins in solution, as well as probably control their

Spider silk protein refolding is controlled by changing pH

Spidroins, the major silk proteins making up the spider's dragline silk, originate in two distinct tissue layers (A and B) in the spider's major ampullate gland. Formation of the complex thread from spidroins occurs in the lumen of the duct connected to the gland. Using pH-sensitive microelectrode probes, we showed that the spidroins traveling through the gland and duct experience a monotonic decr