Purpose.: Instability of the tear film with rapid break-up time is a common feature aqueous-deficient and evaporative dry eye diseases, suggesting that there may be shared structural abnormality responsible for instability. It change in normal meibum lipid composition conformation causes this abnormality. Principle component analyses infrared spectra human indicate collected from donors (Mn) less ordered than meibomian gland dysfunction (Md). In study Md was quantified to test finding....

Purpose: Meibomian gland dysfunction (MGD) is a common clinical problem that often associated with evaporative dry eye disease. Alterations of the lipids meibomian glands have been identified in several studies MGD. This prospective, observational, open-label trial documents improvement both signs and symptoms disease spectroscopic behavior after therapy topical azithromycin ophthalmic solution. Methods: Subjects symptomatic MGD were recruited. Signs evaluated slit lamp. Symptoms measured by...

Purpose: Meibomian gland dysfunction (MGD) is a common clinical problem that often associated with evaporative dry eye disease. Alterations of the lipids meibomian glands have been identified in several studies MGD. This prospective, observational, open-label trial documents improvement both signs and symptoms disease as well spectroscopic characteristics after therapy topical azithromycin ophthalmic solution oral doxycycline treatment. Methods: Subjects symptomatic MGD were recruited. Signs...

Perfluorohexyloctane (PFHO) MIEBOTM, formerly (NOV03) is a single component, water-free eye drop approved by the Food and Drug Administration in United States for treatment of dry disease. We evaluated vitro inhibitory effect PFHO on evaporation rate (Revap) saline. Evaporation rates were measured gravimetrically at 25°C or 35°C. The phosphate-buffered saline (PBS) was following application 11-200 µL 100 artificial tears (Soothe XP [Bausch + Lomb, Bridgewater, New Jersey], Systane Balance...

To determine the phospholipid changes responsible for increase in membrane lipid hydrocarbon chain order, or stiffness, with age and cataract human lens.Clear lenses were pooled into four groups, donors ranging from 15 to 29, 30 49, 50 64, 65 74 years. Whole cataractous obtained after extracapsular extraction. Cataractous grouped classifications: mature, mixed cortical nuclear, immature nuclear sclerotic, mature posterior subcapsular, nuclear. Lipids extracted quantified gravimetrically. The...

purpose. Human lens membranes contain unusually high levels of cholesterol and sphingolipids, lipids known to segregate into liquid-ordered domains. The current study was conducted pursue the determination characterization these domains in clear cataractous human lenses. methods. Cortical nuclear regions aged lenses were obtained. After lysis with Triton X-100 at 4°C sucrose linear-density centrifugation, sedimenting nonsedimenting fractions (when present) collected. Phospholipids analyzed...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTProteolytic activation of the canine cardiac sarcoplasmic reticulum calcium pumpMadeleine A. Kirchberger, Douglas Borchman, and Chinnaswamy KasinathanCite this: Biochemistry 1986, 25, 19, 5484–5492Publication Date (Print):September 23, 1986Publication History Published online1 May 2002Published inissue 23 September 1986https://pubs.acs.org/doi/10.1021/bi00367a021https://doi.org/10.1021/bi00367a021research-articleACS PublicationsRequest reuse...

With increasing age and in patients affected with dry-eye symptoms, the human tear film becomes more unstable exhibits shorter break-up times. We examined whether inclusion of proteins lipids to water evaporation rates measured vitro could account for lower reported previously from vivo measurements. The impact temperature, air flow, humidity on rate tears was vitro.Lipid-protein interactions were using fluorescence spectroscopy performed gravimetrically.Human reflex evaporated at a similar...

Nuclear magnetic resonance (NMR) spectroscopy has been used to quantify lipid wax, cholesterol ester terpenoid and glyceride composition, saturation, oxidation, CH₂ CH₃ moiety distribution. This tool was measure changes in human meibum composition with meibomian gland dysfunction (MGD).(1)H-NMR spectra of from 39 donors (Md) were compared 33 normal (Mn).Principal component analysis (PCA) applied the CH₂/CH₃ regions a set training NMR meibum. PCA discriminated between Mn Md an accuracy 86%....

This study represents a first step toward the evaluation of possible compositional differences in meibum from normal donors (Mn) and with meibomian gland dysfunction (Md) by (1)H-NMR spectroscopy. The results highlight applicability spectroscopy for quantitative analysis waxes, cholesteryl esters, glycerides lipid (ML).Meibum was obtained 41 51 (MGD). used to quantify amount glycerides, esters human meibum.The relative Mn increased age 40% (P < 0.05) lower Md. Interestingly, levels infant...

Purpose: Relationships between tear film lipid (TFL) layer composition, structure, and function could provide insight into the etiology of dry eye. The molar ratio cholesteryl ester (CE)/wax (WE) was measured in meibum from normal donors (Mn) compared with meibomian gland dysfunction (MMGD). Methods: CE/WE using nuclear magnetic resonance spectroscopy. Results: distributed two populations 81% near 0.55 19% 0.3. were higher 13 to 19 years old 1 12 20 88 old. for MMGD 30% lower, 0.34 ± 0.04,...

Calcium is elevated in most cataractous human lenses and may contribute to cataractogenesis. In this study, age-related changes were examined the total calcium content of clear binding lens lipids proteins.Total was determined by atomic absorption spectroscopy. measured light scattering measurement spectroscopy bound unbound fractions.The decreased between 18 55 years age increased 75 years, as well presence cataract. Total levels from subjects with insulin-dependent diabetes did not differ...

PURPOSE. Maintenance of calcium homeostasis is imperative for the clarity lens. Ca 2+ -ATPase essential removal cytosolic calcium, either across plasma membrane or through intracellular organelles such as endoplasmic reticulum. In this study, membranes prepared from clear lens epithelium were compared to cataractous epithelium. METHODS. Human by a protocol utilizing homogenization and centrifugation. activity was measured biochemically using Gamma- 32 P labeled ATP. Lipid order infrared...

Membrane lipid composition varies in different tissues and species. Since a defined is essential to the function of many membranes, relationship between membrane structure was determined using infrared Raman spectroscopy four membranes containing calcium pump: rabbit fast slow twitch muscle sarcoplasmic reticulum human bovine lens fiber cell membranes. We found that sphingolipid phosphatidylcholine content were correlated decrease increase, respectively, CH2 symmetric stretching band...