Search results for "Tears"

Human tear metabolome

2016

The utility of measuring tear film break-up time for prescribing contact lenses.

2017

Abstract Purpose To evaluate the clinical value of non-invasive keratograph tear film breakup time (NIKBUT) in the assessment of pre-corneal and pre-lens tear film quality for prescribing contact lenses (CLs). Methods Forty-six subjects aged 25.5 ± 4.3 (mean ± standard deviation) years were recruited. Visual acuity (VA), anterior eye health checks and NIKBUT were evaluated. On the following day, subjects were fitted with a daily Silicon Hydrogel (SiHy) CL in one eye and a Hydrogel (Hy) CL in the other. After four hours one material for both eyes was chosen based on a qualitative analysis which included VA, CL fitting and comfort. Information about the first and the mean NIKBUT was then cont…

Effect of contact lens surface properties on comfort, tear stability and ocular physiology.

2018

Aim: Retrospective analysis of different contact lens wearing groups suggests lens surface lubricity is the main factor influencing contact lens comfort. However, the examined commercially available contact lenses differ in material and design as well as surface properties. Hence this study isolates the contribution of lens surface properties using an ultra-thin coating technology. Methods: Nineteen habitual contact lens wearers (21.6. ±. 1.7years) wore formofilcon B soft monthly disposable contact lenses with and without coating technology modified surface properties for a month each in a randomised double-masked cross-over study. Objective non-invasive: breakup time (NIKBUT), NIKBUT avera…

2016

AbstractDespite the high global prevalence of dry eye syndrome (DES), the fundamental processes underlying this pathology remain largely unexplored. Therefore, this study endeavoured to investigate in-depth the tear proteome of DES patients employing the mass spectrometry (MS)-based proteomic strategies. Eighty patients were recruited and subdivided into three major DES subgroups, which are the aqueous-deficient (DRYaq), evaporative (DRYlip) and a combination of the two (DRYaqlip), as well as healthy subjects (CTRL). Discovery proteomics strategy was employed to identify large number of significantly differentially expressed tear proteins in DRYlip vs. CTRL, DRYaq vs. CTRL and DRYaqlip vs. …

The tear turnover and tear clearance tests – a review

2018

Introduction. The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered. Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on t…

Does endogenous serum oestrogen play a role in meibomian gland dysfunction in postmenopausal women with dry eye?

2016

Aim To explore the relationship between serum concentration of sex hormones and dry eye symptoms and signs in postmenopausal women. Methods A cross-sectional analysis was undertaken. Subjects were 46 postmenopausal women with dry eye (mean age 64.4±5.2 years, 13.7±6.4 years since menopause; not undergoing hormone replacement therapy). Ocular symptoms (Ocular Surface Disease Index (OSDI) and Ocular Comfort Index (OCI)), tear function (tear osmolarity, non-invasive tear break-up time, tear secretion), corneal and conjunctival staining, and meibomian gland (MG) appearance, were recorded. Venous blood was collected and serum concentrations of 17β-oestradiol (E2), 3-α-androstanediol-glucuronide …

Determination of inmune response and inflammation mediators in tears: Changes in dry eye and glaucoma as compared to healthy controls

2017

Objective To determine the expression profile of immune response and inflammation (IRI) mediator molecules in tears from patients with dry eye (DE), and those suspected of having or have primary open-angle glaucoma (POAG) under treatment and compare them with healthy controls. Methods A prospective observational cohort study including 107 participants sub-divided into: healthy controls (CG; n = 30), patients with DE (DEG; n = 41) and patients suspected of having or have POAG and on hypotensive treatment (POAG-G; n = 36). Tear samples were collected by capillary to be processed using a multi-immunoassay system based on flow cytometry (Luminex R-200®), in order to determine the interleukins (…

The contribution of tear osmolarity measurement to ocular surface assessment in contact lens wearers

2012

Purpose: To determine whether tear osmolarity using the TearLabTM Osmolarity System contributes to the assessment of the ocular surface in contact lens (CL) wearers.Methods: Data were collected from 44 CL wearers (28 tolerant and 16 intolerant) and 34 healthy subjects. Every patient underwent a thorough ophthalmic examination and tear osmolarity test, conjunctival impression cytology and meibomian lipid sampling. Symptoms, break-up time (BUT), tear osmolarity, conjunctival expression of HLA-DR and meibomian fatty acid composition were evaluated.Results: Tear osmolarity was significantly higher in the controls compared to tolerant and intolerant CL wearers (p=0.0007). Flow cytometry results …

Analysis of tear proteins by one- and two-dimensional thin-layer iosoelectric focusing, sodium dodecyl sulfate electrophoresis and lectin blotting. D…

1998

· 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…

A metabolomic approach to dry eye disorders. The role of oral supplements with antioxidants and omega 3 fatty acids.

2014

Purpose We used nuclear magnetic resonance spectroscopy of hydrogen-1 nuclei (1H NMR S) to analyze the metabolic profile of reflex tears from patients with dry eye disorders. Methods We performed a prospective case-control study involving 90 participants: 55 patients diagnosed with dry eye syndrome (DESG) and 35 healthy subjects (control group, CG). From the DESG, two subgroups were formed: mild DES (n=22) and moderate DES (n=33). Participants were prescribed an oral nutraceutic supplementation containing antioxidants and essential polyunsaturated fatty acids to be taken as three capsules per day for 3 months. Reflex tears (20–30 µl) were collected from the tear meniscus of both eyes of eac…