Scan Science and Technology
Contact Leading Edge Experts & Companies
The Experts below are selected from a list of 27399 Experts worldwide ranked by ideXlab platform
Abhijith K. Anil – One of the best experts on this subject based on the ideXlab platform.
Proteomics of human Aqueous Humor.Omics : a journal of integrative biology, 2015Co-Authors: Krishna R Murthy, Pavithra Rajagopalan, Sneha M. Pinto, Jayshree Advani, Praveen R. Murthy, Renu Goel, Yashwanth Subbannayya, Lavanya Balakrishnan, Mahashweta Dash, Abhijith K. AnilAbstract:
The Aqueous Humor is a colorless, transparent fluid that fills the anterior chamber of the eye. It plays an important role in maintaining the intraocular pressure and providing nourishment to the lens and cornea. The constitution of the Aqueous Humor is controlled by the blood-Aqueous barrier. Though this ocular fluid has been extensively studied, its role in ocular physiology is still not completely understood. In this study, Aqueous Humor samples were collected from 250 patients undergoing cataract surgery, subjected to multiple fractionation strategies and analyzed on a Fourier transform LTQ-Orbitrap Velos mass spectrometer. In all, we identified 763 proteins, of which 386 have been identified for the first time in this study. Sorbitol dehydrogenase (SORD), filensin (BFSP1), and phakinin (BFSP2) are some of the proteins that have not been previously reported in the Aqueous Humor. Gene Ontology analysis revealed 35% of the identified proteins to be extracellular, with a majority of them involved in cell communication and signal transduction. This study comprehensively reports 386 novel proteins that have important potential as biomarker candidates for future research into personalized medicine and diagnostics aimed towards improving visual health.
Otto Closs – One of the best experts on this subject based on the ideXlab platform.
Quantitation of alpha crystallin in human Aqueous Humor by radioimmunoassay.Acta Ophthalmologica, 2009Co-Authors: Hans Otto Sandberg, Ivar Folling, Otto ClossAbstract:
A method for quantitation of alpha crystallin in individual samples of human Aqueous Humor by radioimmunoassay is described. The concentration of alpha crystallin in Aqueous Humor from 48 eyes with cataract and three eyes with clear lenses was at or below 0.006 μg/ml. Two samples from eyes with heterochromic cataract contained 0.011 and 0.012 μg/ml, respectively. Alpha crystallin is probably not among those lens proteins described earlier in normal human Aqueous Humor.
Robert N Weinreb – One of the best experts on this subject based on the ideXlab platform.
Aqueous Humor dynamics in miceInvestigative Ophthalmology & Visual Science, 2003Co-Authors: Makoto Aihara, James D Lindsey, Robert N WeinrebAbstract:
PURPOSE: To assess Aqueous Humor dynamics in mouse eyes. METHODS: Aqueous Humor dynamics of NIH Swiss White mouse were assessed with an injection and aspiration system, using fine glass microneedles. Intraocular pressure (IOP) was measured by a microneedle connected to a pressure transducer. Episcleral venous pressure (EVP) was measured by gradually lowering intracameral pressure until blood reflux into Schlemm’s canal was observed. Outflow facility (C) was determined based on constant pressure perfusion measurements obtained at two different IOPs. Aqueous volume (V(a)) was determined by direct measurement of aspirated Aqueous Humor. Aqueous Humor production (F(a)) was measured by the dilution method with rhodamine-dextran. Conventional and uveoscleral outflow (F(c) and F(u), respectively), as well as the turnover rate of Aqueous Humor, were also calculated. RESULTS: IOP and EVP were 15.7 +/- 2.0 and 9.5 +/- 1.2 mm Hg, respectively (n = 20). F(a) was 0.18 +/- 0.05 microL/min (mean +/- SD; n = 8). C was 0.0051 +/- 0.0006 microL/min per mm Hg (n = 8). Estimated F(c) and F(u) were 0.032 and 0.148 microL/min, respectively. F(c) was 18% of F(a). F(u) was 82% of F(a). V(a) was 5.9 +/- 0.5 microL (n = 8). The calculated turnover rate of Aqueous Humor was 2.5%. CONCLUSIONS: The mouse eye has similar Aqueous production and Aqueous Humor turnover rate as the human eye. The presence of both conventional and uveoscleral outflow suggests that the mouse is a useful model system for further investigations of the biology of Aqueous dynamics.
Physiological factors in the circadian rhythm of protein concentration in Aqueous Humor.Investigative ophthalmology & visual science, 1998Co-Authors: John H.k. Liu, James D Lindsey, Robert N WeinrebAbstract:
PURPOSE. The authors addressed three questions concerning the circadian rhythm of Aqueous Humor protein concentration in rabbits. First, is there an endogenous oscillator for this circadian rhythm? Second, does a circadian rhythm occur for individual Aqueous Humor protein components? Third, what is the role of ocular sympathetic nerves, which are more active in the dark phase, in this circadian rhythm? METHODS. Adult New Zealand albino rabbits were entrained to a daily 12-hour light/12-hour dark cycle. Under a constant dark environment for 24 hours, rabbits were killed at 4-hour intervals, beginning at 2 hours before the onset of the subjective light phase. Eight rabbits were used for each of the six time points. Aqueous Humor and vitreous Humor were collected, and their protein concentrations were determined. Major Aqueous Humor protein components were resolved by polyacrylamide gel electrophoresis (PAGE), stained with silver reagent, and analyzed using densitometry. Another group of eight light-dark- entrained rabbits underwent unilateral transection of the cervical sympathetic trunk. Three weeks after the operation, the circadian elevation of intraocular pressure (IOP) at 2 hours into the dark phase was determined for both eyes. Rabbits were later killed at this time point, and total protein concentrations in Aqueous Humor and vitreous Humor were determined in both eyes. Major Aqueous Humor protein components in both eyes were resolved by PAGE and were compared. REsuLTs. In light-dark-entrained rabbits, a circadian rhythm of protein concentration appeared in the Aqueous Humor under a constant dark environment. Total protein concentration in Aqueous Humor increased sharply in the early subjective light phase, remained relatively high during the remainder of the subjective light phase, and decreased in the subjective dark phase. Analyses of albumin and other abundant proteins in the Aqueous Humor showed that all of them varied similarly in a circadian pattern. In contrast, total protein concentration in the vitreous Humor remained unchanged. In rabbits with unilaterally decentralized ocular sympathetic nerves, total protein concentrations in the Aqueous Humor and the vitreous Humor in the early dark phase showed no difference between the two eyes. In addition, there was no difference in individual Aqueous Humor protein concentration between the two eyes. However, the nocturnal IOP elevation in the decentralized eye was less than that in the contralateral, intact eye. CoNcLUsioNs. The circadian rhythm of Aqueous Humor protein concentration in rabbits can continue without an external signal of dark-light change, indicating the existence of an endogenous oscillator. A similar circadian rhythm occurs for various major Aqueous Humor protein components. The nocturnal increase in ocular sympathetic activities plays a limited role in the circadian rhythm of Aqueous Humor protein concentration.
Lysosomal enzyme activity in human Aqueous HumorClinica chimica acta; international journal of clinical chemistry, 1991Co-Authors: Robert N Weinreb, Shyun Jeng, Arnold L. MillerAbstract:
Abstract Activity of the lysosomal enzymes N-acetyl-β-D-hexosaminidase, α-D-mannosidase, β-D-glucuronidase, and β-D-galactosidase was detected in Aqueous Humor from eyes undergoing intraocular surgery. There was no correlation between lysosomal enzyme activity and age. Lysosomal enzyme activity in human Aqueous Humor most likely reflects the total amount of lysosomal enzyme activity released by ocular tissues surrounding the anterior chamber including the cornea, trabecular meshwork, ciliary body, iris, and lens. Their release into Aqueous Humor may have a role in regulating Aqueous outflow in normal and glaucomatous eyes.