Abstract:
PURPOSE:To synthesize and characterize hydrogels with viscoelastic properties comparable to those of the natural lens. METHODS:Hydrogels were synthesized in water by free-radical polymerization of the monomer poly(ethyleneglycol)-monomethacrylate. Three different molecular weights of poly(ethyleneglycol)-dimethacrylates were used as crosslinkers. For each crosslinker used, five different monomer-to-crosslinker weight ratios were utilized while the total mass of the reactants was kept constant. In another series, the concentration of the reactants was varied while the weight ratio of monomer to crosslinker was kept constant at 95 : 5. The percent optical transmission, equilibrium water content, moduli (elastic, shear, storage, and loss), and retardation time constant of the hydrogels were determined. In addition, endocapsular polymerization was performed in the capsular bag of porcine eyes. RESULTS:The hydrogels examined exhibited the following ranges for viscoelastic properties: elastic modulus, 1.33-2.37 x 10(4) Pa; shear modulus, 3.35-6.72 x 10(3) Pa; storage modulus, 1.65-6.24 x 10(4) Pa. For any given hydrogel, raising its crosslinker's weight ratio increased its moduli and decreased its equilibrium water content and optical transmission. For any given monomer-to-crosslinker weight ratio, increasing the molecular weight of the crosslinker reversed these trends. Reactant concentrations increased the elastic modulus and decreased the equilibrium water content. The hydrogels formed ex vivo (in the evacuated capsular bag of porcine eyes) allowed for the clear and undistorted viewing of objects. CONCLUSIONS:Hydrogels that exhibit physical and mechanical properties comparable to those of the natural lens were successfully identified, synthesized, and characterized, and the feasibility of endocapsular polymerization was demonstrated.
journal_name
Curr Eye Resjournal_title
Current eye researchauthors
Murthy SK,Ravi Ndoi
10.1076/ceyr.22.5.384.5493subject
Has Abstractpub_date
2001-05-01 00:00:00pages
384-93issue
5eissn
0271-3683issn
1460-2202journal_volume
22pub_type
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1080/02713683.2017.1370118
更新日期:2018-01-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713683.2010.512114
更新日期:2010-12-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689008999599
更新日期:1990-06-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689309024629
更新日期:1993-05-01 00:00:00
abstract:PURPOSE:To examine the morphological changes in the meibomian glands of eyes of patients with dry eye disease using the non-contact infrared meibography system and to assess their relationship with meibomian dropout, signs, and tear-film function. METHODS:Subjects included 264 randomly selected patients (528 eyes) suf...
journal_title:Current eye research
pub_type: 杂志文章
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更新日期:2014-10-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1076/ceyr.16.4.320.10697
更新日期:1997-04-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689609017650
更新日期:1996-10-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713683.2010.483312
更新日期:2010-08-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688408997233
更新日期:1984-03-01 00:00:00
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pub_type: 杂志文章
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更新日期:2001-10-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713683.2011.573899
更新日期:2011-07-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1076/ceyr.16.10.1061.9020
更新日期:1997-10-01 00:00:00
abstract::Calmodulin has been shown to perform several important functions in the lens including regulation of the plasma membrane Ca(2+)-ATPase. This study investigated the effects of a variety of different CaM antagonists on rat lens membrane potential, membrane resistance, intracellular Na+ and Ca2+ content and transparency,...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689408995780
更新日期:1994-03-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713683.2014.997887
更新日期:2016-01-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:
更新日期:1998-08-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688508999972
更新日期:1985-02-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1076/ceyr.16.6.600.5084
更新日期:1997-06-01 00:00:00
abstract::VIP markedly stimulates intracellular cAMP accumulation in the human retinoblastoma Y-79 cell line. cAMP increased about 5-fold above the basal level with 10(-8)M VIP and reached a maximum level (about 70-fold increase) with 2 X 10(-6)M VIP. Glucagon at 6 X 10(-8)M significantly increased cAMP accumulation with a maxi...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688408997218
更新日期:1984-02-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688108998358
更新日期:1981-01-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688609015101
更新日期:1986-02-01 00:00:00
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更新日期:2020-09-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688608995161
更新日期:1986-01-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1080/02713680902964892
更新日期:2009-07-01 00:00:00
abstract::The initial rapid fall in tear film fluorescence after instilling a 1 microliter drop of fluorophore could be a result of stimulated tear flow or of distribution of the dye throughout the tear fluid present in the conjunctival sac. An attempt was made to decide this by comparing the fall in fluorescence of two differe...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689509033526
更新日期:1995-04-01 00:00:00
abstract::The effects of transforming growth factor-beta (TGF beta) and epidermal growth factor (EGF) on the synthesis of collagen and fibronectin, and on the proliferation of human corneal stromal fibroblasts in vitro, were evaluated. Human corneal stromal fibroblasts in culture were incubated for 48 hours with TGF beta or EGF...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713689308995765
更新日期:1993-08-01 00:00:00
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journal_title:Current eye research
pub_type: 杂志文章
doi:10.1080/02713680802245772
更新日期:2008-08-01 00:00:00
abstract:BACKGROUND:To compare the intensity of posterior capsule opacification (PCO) between two intraocular lenses (IOLs) of the same optic material, but with different haptic design (1-piece vs. 3-piece). METHODS:This prospective intraindividual controlled cohort study comprised eighty eyes of 40 patients with bilateral age...
journal_title:Current eye research
pub_type: 杂志文章,随机对照试验
doi:10.3109/02713683.2012.717242
更新日期:2013-01-01 00:00:00
abstract:PURPOSE:Current standard of care for neovascular eye diseases require repeated intravitreal bolus injections of anti-vascular endothelial growth factors (anti-VEGFs). The purpose of this study was to validate a degradable microsphere-thermoresponsive hydrogel drug delivery system (DDS) capable of releasing bioactive af...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.1080/02713683.2018.1533983
更新日期:2019-03-01 00:00:00
abstract::Adult albino mice received tritiated thymidine either injected subcutaneously (333 microCi) every 6 hours for up to 36 hours, or administered in their drinking water for up to 74 days (about 45 microCi/day). Tissue sections were examined with autoradiography to determine the distribution of the label. Animals receivin...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.3109/02713688809047029
更新日期:1988-03-01 00:00:00
abstract:PURPOSE:To study the effect of cataract surgery with intraocular lens (IOL) on frequency doubling perimetry (FDP). METHODS:Patients aged 40 years or above seen at our outpatient clinic with no ocular pathology except for visually significant cataract and visual acuity 6/24 or better were eligible. They underwent FDP b...
journal_title:Current eye research
pub_type: 杂志文章
doi:10.1080/02713680490904278
更新日期:2005-02-01 00:00:00