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Waghmare SV, Jeria S. A Review of Contact Lens-Related Risk Factors and Complications. Cureus 2022; 14:e30118. [PMID: 36381898 PMCID: PMC9644230 DOI: 10.7759/cureus.30118] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 10/10/2022] [Indexed: 11/05/2022] Open
Abstract
The purpose of this article is to develop a modern strategy for handling difficulties related to contact lenses and their care. A growing number of people throughout the world are currently concerned by eye-related undesirable activities in allergy sufferers and those wearing contact lenses. While many wearers who experience ocular discomfort exhibit dryness as a symptom, many other contact lens-related pain symptoms also include irritation and fatigue, and managing coexisting diseases must be done in accordance with aspects of wearing contact lenses, all of which undoubtedly increase discomfort. It is typical for contact lens storage containers to have persistent microbial contamination, which has been linked to microbial keratitis (MK) and clear corneal invasion. Contact lens-associated MK is an interesting, potentially sight-threatening complexity arising from wearing soft contact lenses. Estimates show that for every 10,000 persons who wear contact lenses each year, there are 2 to 5 occurrences of MK. Investigating separate determinants for contact lens-associated MK and evaluating their impact on infection load is one of the challenges in their administration. It is hoped that this will offer a useful outline of the complicated issues of contact lens wear that are both infectious and non-infectious. Recent epidemiological studies detailing the risk factors associated with contact lens use, and the effect of pathogen and individual immune profiles on the severity of diseases have enlightened how we might interpret the prophylaxis and prevention of contact lens-related corneal infection. The most dreaded side effect of contact lens use, infectious keratitis linked with contact lenses, will be reviewed, along with the most recent advancements in its diagnosis and treatment.
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Masoudi S, Willcox M. A method for studying lipid adsorption to silicone hydrogel contact lenses. BIOFOULING 2021; 37:862-878. [PMID: 34615411 DOI: 10.1080/08927014.2021.1978433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 08/30/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
The aim of this study was to develop an experimental methodology to measure lipid deposition with contact lenses. Contact lenses were incubated in a lipid solution. The amount and types of adsorbed lipids were assessed using mass spectrometry and confocal microscopy. The recovery of lipids from lenses varied with lipid and lens type. Most non-polar and polar lipids were desorbed from lenses during the first 5 min of extraction. Fluorescently labelled phosphatidylcholine bound within the matrix of Senofilcon A lenses but to the surface of Lotrafilcon B lenses, whereas fluorescently labelled cholesteryl ester was found throughout both lenses. The efficacy of extraction of lipids from contact lenses varies for different lipid classes and different lens materials. Differences in the amount and time of lipid desorption probably resulted from the strength of the bond between lipid and lens polymer and the depth of adsorption of lipid in the polymer.
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Affiliation(s)
- Simin Masoudi
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Mark Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
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CLEAR - Contact lens complications. Cont Lens Anterior Eye 2021; 44:330-367. [DOI: 10.1016/j.clae.2021.02.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 02/01/2021] [Indexed: 12/20/2022]
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Chatterjee S, Upadhyay P, Mishra M, M. S, Akshara MR, N. K, Zaidi ZS, Iqbal SF, Misra SK. Advances in chemistry and composition of soft materials for drug releasing contact lenses. RSC Adv 2020; 10:36751-36777. [PMID: 35517957 PMCID: PMC9057048 DOI: 10.1039/d0ra06681h] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 09/20/2020] [Indexed: 11/21/2022] Open
Abstract
Ocular drug delivery has always been a challenging feat to achieve in the field of medical sciences. One of the existing methods of non-invasive ocular drug delivery is the use of eye drops. However, drugs administered through these formulations have low bioavailability in the ocular system. This limitation can been overcome by using contact lenses as drug delivery vehicles. According to USA FDA definitions they can be categorized into two main categories-hard and soft contact lenses. Based on the material properties, hard contact lenses are mostly produced from polymers of acrylate monomers such as MMA (methyl methacrylate). These have the least water retention capacity, thereby, having minimal ability to diffuse oxygen into the corneal layer and are not ideal for long term use. Soft material contact lenses are flexible and are mainly hydrogel based. They have higher water retention capacities as compared to rigid contact lenses, which gives them the ability to transmit oxygen to the corneal layer. These hydrogel based soft materials are mainly produced from polymers of acrylate monomers such as HEMA (hydroxyethyl methacrylate) and found to be better for drug delivery contact lenses. These polymer-based soft materials have been efficiently modified in terms of their chemistry to achieve diverse physicochemical properties to produce efficient ocular drug delivery systems. However, complications such as drug leaching during storage and distribution, sterilisation, preservation of integrity of the lens and the possibility of surface roughness due to the incorporated drug molecules still need to be optimised. This review highlights the chemistries of various polymeric molecules through which physicochemical properties can be modified to achieve optimum drug loading and sustained release of the drug for application in the ocular system. Contact lens as controllable route for ocular drug delivery.![]()
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Affiliation(s)
- Subir Chatterjee
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Prashant Upadhyay
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Manjul Mishra
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Srividya M.
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - M. R. Akshara
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Kamali N.
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Zahra Sifat Zaidi
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Sayeda F. Iqbal
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
| | - Santosh K. Misra
- Department of Biological Sciences & Bioengineering
- Indian Institute of Technology Kanpur
- Kalyanpur
- India-208016
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Abstract
The purpose of this article is to provide a review of existing literature describing complications with contemporary contact lenses and their management. It is envisioned that this will serve as a useful summary of noninfectious and infectious complications associated with contact lens wear.
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A novel murine model for contact lens wear reveals clandestine IL-1R dependent corneal parainflammation and susceptibility to microbial keratitis upon inoculation with Pseudomonas aeruginosa. Ocul Surf 2018; 17:119-133. [PMID: 30439473 DOI: 10.1016/j.jtos.2018.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/06/2018] [Accepted: 11/09/2018] [Indexed: 12/17/2022]
Abstract
PURPOSE Contact lens wear carries a risk of complications, including corneal infection. Solving these complications has been hindered by limitations of existing animal models. Here, we report development of a new murine model of contact lens wear. METHODS C57BL/6 mice were fitted with custom-made silicone-hydrogel contact lenses with or without prior inoculation with Pseudomonas aeruginosa (PAO1-GFP). Contralateral eyes served as controls. Corneas were monitored for pathology, and examined ex vivo using high-magnification, time-lapse imaging. Fluorescent reporter mice allowed visualization of host cell membranes and immune cells. Lens-colonizing bacteria were detected by viable counts and FISH. Direct-colony PCR was used for bacterial identification. RESULTS Without deliberate inoculation, lens-wearing corneas remained free of visible pathology, and retained a clarity similar to non-lens wearing controls. CD11c-YFP reporter mice revealed altered numbers, and distribution, of CD11c-positive cells in lens-wearing corneas after 24 h. Worn lenses showed bacterial colonization, primarily by known conjunctival or skin commensals. Corneal epithelial cells showed vacuolization during lens wear, and after 5 days, cells with phagocyte morphology appeared in the stroma that actively migrated over resident keratocytes that showed altered morphology. Immunofluorescence confirmed stromal Ly6G-positive cells after 5 days of lens wear, but not in MyD88 or IL-1R gene-knockout mice. P. aeruginosa-contaminated lenses caused infectious pathology in most mice from 1 to 13 days. CONCLUSIONS This murine model of contact lens wear appears to faithfully mimic events occurring during human lens wear, and could be valuable for experiments, not possible in humans, that help solve the pathogenesis of lens-related complications.
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Brygoła R, Sęk S, Sokołowski M, Kowalczyk-Hernández M, Pniewski J. Limits in measurements of contact lens surface profile using atomic force microscopy. Colloids Surf B Biointerfaces 2018; 165:229-234. [DOI: 10.1016/j.colsurfb.2018.02.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/17/2017] [Accepted: 02/10/2018] [Indexed: 11/25/2022]
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Fabrication of starch-graft-poly(acrylamide)/graphene oxide/hydroxyapatite nanocomposite hydrogel adsorbent for removal of malachite green dye from aqueous solution. Int J Biol Macromol 2018; 106:101-115. [DOI: 10.1016/j.ijbiomac.2017.07.182] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 07/07/2017] [Accepted: 07/31/2017] [Indexed: 01/11/2023]
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Hosseinzadeh H, Bahador N. Novel CdS quantum dots templated hydrogel nanocomposites: Synthesis, characterization, swelling and dye adsorption properties. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.05.129] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Jafarnejad E, Ramin S, Ghanbarizadeh M. Synthesis and characterization nanocomposite of the graphene oxide/polyacrylic acid modified with 2-mercaptoethanol. POLYMER SCIENCE SERIES B 2016. [DOI: 10.1134/s1560090416030088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Differences in Dry Eye Questionnaire Symptoms in Two Different Modalities of Contact Lens Wear: Silicone-Hydrogel in Daily Wear Basis and Overnight Orthokeratology. BIOMED RESEARCH INTERNATIONAL 2016; 2016:1242845. [PMID: 27689073 PMCID: PMC5022233 DOI: 10.1155/2016/1242845] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 07/31/2016] [Accepted: 08/01/2016] [Indexed: 11/17/2022]
Abstract
Purpose. To compare the ocular surface symptoms and signs in an adult population of silicone-hydrogel (Si-Hy) contact lens (CL) wearers with another modality of CL wear, overnight orthokeratology (OK). Materials and Methods. This was a prospective and comparative study in which 31 myopic subjects were fitted with the same Si-Hy CL and 23 underwent OK treatment for 3 months. Dry eye questionnaire (DEQ) was filled in at the beginning of the study and then after 15 days, 1 month, and 3 months using each CL modality. The tear quality was evaluated with noninvasive tear break-up time. Tear production was measured with Schirmer test. Tear samples were collected with Schirmer strips being frozen to analyze the dinucleotide diadenosine tetraphosphate (Ap4A) concentration with High-Performance Liquid Chromatography (HPLC). Results. After refitting with ortho-k, a reduction in discomfort and dryness symptoms at the end of the day (p < 0.05, χ2) was observed. No significant changes were observed in Ap4A concentration in any group. Bulbar redness, limbal redness, and conjunctival staining increased significantly in the Si-Hy group (p < 0.05, Kruskal-Wallis test). Conclusion. Discomfort and dryness symptoms at the end of the day are lower in the OK CL group than in the Si-Hy CL group.
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Hosseinzadeh H, Ramin S. Magnetic and pH-responsive starch-g-poly(acrylic acid-coacrylamide)/graphene oxide superabsorbent nanocomposites: One-pot synthesis, characterization, and swelling behavior. STARCH-STARKE 2015. [DOI: 10.1002/star.201500069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Sonia Ramin
- Department of Chemistry; Payame Noor University; Tehran Iran
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14
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Impact of Cosmetics on the Surface Properties of Silicone Hydrogel Contact Lenses. Eye Contact Lens 2015; 41:228-35. [DOI: 10.1097/icl.0000000000000101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Performance of three multipurpose disinfecting solutions with a silicone hydrogel contact lens. BIOMED RESEARCH INTERNATIONAL 2015; 2015:216932. [PMID: 25918703 PMCID: PMC4396003 DOI: 10.1155/2015/216932] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 03/04/2015] [Accepted: 03/09/2015] [Indexed: 11/18/2022]
Abstract
Purpose. To evaluate the clinical performance of a silicone hydrogel (Si-Hy) soft contact lens (CL) in combination with three different multipurpose disinfecting solutions (MPDSs). Methods. This was a prospective, randomized, single-masked, crossover, and comparative study in which 31 habitual soft CL wearers were randomly assigned to one of the three MPDSs (Synergi, COMPLETE RevitaLens, and OPTI-FREE PureMoist) for 1 month with a 1-week wash-out period between each exposure. All subjects were successfully refitted with a Si-Hy CL (Biofinity). Subjects were then scheduled for follow-up visits after 1 month of lens wear, being evaluated at 2 and 8 hours after lens insertion. Visual Analogue Scales (VAS) were used to gauge comfort rating. Results. The tarsal conjunctiva showed a significantly different degree of lid redness between the MPDSs at the 2-hour visit (P < 0.05, Kruskal-Wallis test), being lower for COMPLETE RevitaLens compared to the other two MPDSs (Mann-Whitney U test). Furthermore, a significantly different degree of lid roughness at the 8-hour visit was seen (P < 0.05, Kruskal-Wallis test), being higher for Synergi (Mann-Whitney U test). The subjective comfort was similar with the three MPDSs. Conclusion. Tarsal conjunctival response should be also considered in the context of the clinical performance of MPDs at the ocular surface.
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Hosseinzadeh H, Zoroufi S, Mahdavinia GR. Study on adsorption of cationic dye on novel kappa-carrageenan/poly(vinyl alcohol)/montmorillonite nanocomposite hydrogels. Polym Bull (Berl) 2015. [DOI: 10.1007/s00289-015-1340-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Chyasnavichyus M, Young SL, Tsukruk VV. Mapping micromechanical properties of soft polymer contact lenses. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.09.053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Cirillo G, Hampel S, Spizzirri UG, Parisi OI, Picci N, Iemma F. Carbon nanotubes hybrid hydrogels in drug delivery: a perspective review. BIOMED RESEARCH INTERNATIONAL 2014; 2014:825017. [PMID: 24587993 PMCID: PMC3918724 DOI: 10.1155/2014/825017] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 10/27/2013] [Accepted: 10/31/2013] [Indexed: 11/17/2022]
Abstract
The use of biologics, polymers, silicon materials, carbon materials, and metals has been proposed for the preparation of innovative drug delivery devices. One of the most promising materials in this field are the carbon-nanotubes composites and hybrid materials coupling the advantages of polymers (biocompatibility and biodegradability) with those of carbon nanotubes (cellular uptake, stability, electromagnatic, and magnetic behavior). The applicability of polymer-carbon nanotubes composites in drug delivery, with particular attention to the controlled release by composites hydrogel, is being extensively investigated in the present review.
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Affiliation(s)
- Giuseppe Cirillo
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
- Leibniz Institute for Solid State and Materials Research Dresden, Postfatch 270116, 01171 Dresden, Germany
| | - Silke Hampel
- Leibniz Institute for Solid State and Materials Research Dresden, Postfatch 270116, 01171 Dresden, Germany
| | - Umile Gianfranco Spizzirri
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Ortensia Ilaria Parisi
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Nevio Picci
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Francesca Iemma
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende, Italy
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Abdel-Halim E. Preparation of starch/poly(N,N-Diethylaminoethyl methacrylate) hydrogel and its use in dye removal from aqueous solutions. REACT FUNCT POLYM 2013. [DOI: 10.1016/j.reactfunctpolym.2013.08.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
In response to patient demands for extended contact lens wearing times, the contact lens industry has developed novel silicone-hydrogel (SiHy) lens materials that combine the enhanced oxygen permeability of silicone polymers with the water-based comfort of conventional hydrogels. In the past 12 years since the successful launch of these SiHy lenses, much has been learned about their ability to provide the biocompatibility necessary to sustain ocular health and comfort. A review of the unique physiologic requirements for a successful extended wear lens and how the first and current SiHy lenses address them is provided.
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Sorour MH, El Sayed MM, Abd El Moneem NM, Talaat HA, Shaalan HF, El Marsafy SM. Process and financial considerations pertinent to hydrogel manufacture. STARCH-STARKE 2012. [DOI: 10.1002/star.201200181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Chan KY, Cho P, Chan YY, Cheung SW, Swann PG. Prevalence of papillary changes and folliculosis of the palpebral conjunctiva in asymptomatic Chinese children. Cont Lens Anterior Eye 2012; 36:62-5. [PMID: 23153728 DOI: 10.1016/j.clae.2012.10.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 08/27/2012] [Accepted: 10/02/2012] [Indexed: 10/27/2022]
Abstract
PURPOSE To determine the prevalence of papillary changes of the upper palpebral conjunctiva and folliculosis of the lower palpebral conjunctiva in Chinese children with no history of contact lens wear. METHOD Ninety-nine subjects (aged 6-15 years old) who were interested in a myopia control study were screened for papillary changes and folliculosis of the palpebral conjunctiva. Photodocumentation was performed under white and blue light (after the application of fluorescein) with a yellow filter and the photographs were graded by a group of practitioners according to a pre-set grading scale. Analysis was performed with the subjects divided into groups according to gender and age. RESULTS More than 48% of the subjects had clinically significant (≥Grade 3) papillary changes in the upper palpebral conjunctiva. The prevalence of significant folliculosis in the lower lid was about 33%. The prevalence of significant papillary changes and folliculosis were similar between genders. No differences were observed between younger (age≤10 years old) and older (age>10 years old) in papillary changes but younger subjects showed a higher prevalence of folliculosis. CONCLUSIONS The prevalences of clinically significant papillary changes and folliculosis of unknown aetiology are high in Chinese children.
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Affiliation(s)
- Ka Yin Chan
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong.
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Sorour M, El-Sayed M, Moneem NAE, Talaat HA, Shalaan H, Marsafy SE. Characterization of hydrogel synthesized from natural polysaccharides blend grafted acrylamide using microwave (MW) and ultraviolet (UV) techniques. STARCH-STARKE 2012. [DOI: 10.1002/star.201200108] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Bortolin A, Aouada FA, Longo E, Mattoso LHC. Investigação do processo de absorção de água de hidrogéis de polissacarídeo: efeito da carga iônica, presença de sais, concentrações de monômero e polissacarídeo. POLIMEROS 2012. [DOI: 10.1590/s0104-14282012005000046] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neste trabalho foi reportada a caracterização de hidrogéis constituídos por metilcelulose (MC) e poliacrilamida (PAAm) preparados pelo processo de reticulação cruzada. As propriedades espectroscópicas e morfológicas foram investigadas por espectroscopia no infravermelho com transformada de Fourier e microscopia eletrônica de varredura, respectivamente. O efeito da carga iônica, presença de sais, concentrações de monômero AAm e polissacarídeo MC na absorção de água e nas propriedades cinéticas dos hidrogéis foi detalhadamente investigado. Os resultados indicaram que o decréscimo da concentração de MC ou aumento da concentração de AAm, carga iônica do contra-íon do sal de cloreto e a presença de fertilizante no meio externo de intumescimento provocaram diminuição significativa na absorção de água dos hidrogéis. O mecanismo de absorção de água dos hidrogéis de PAAm-MC em água seguiu o modelo de difusão Fickiana; já o mecanismo dos hidrogéis intumescidos em sais (cloreto ou fertilizante) seguiu o modelo de transporte anômalo. Pela alta e rápida absorção de água, as matrizes porosas e tridimensionais compostas por PAAm e MC podem em potencial ser aplicadas na agricultura como veículos carreadores.
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Guillon M, Maïssa C. Long term effects of the daily wear of senofilcon A silicone hydrogel contact lenses on eyelid tissues. Cont Lens Anterior Eye 2012; 35:112-7. [DOI: 10.1016/j.clae.2012.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 12/12/2011] [Accepted: 01/12/2012] [Indexed: 10/28/2022]
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Polymer hydrogel from carboxymethyl guar gum and carbon nanotube for sustained trans-dermal release of diclofenac sodium. Int J Biol Macromol 2011; 49:885-93. [DOI: 10.1016/j.ijbiomac.2011.08.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/01/2011] [Accepted: 08/03/2011] [Indexed: 12/16/2022]
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Ahmed AESI. Hydrogels for water filters: Preparation and antibacterial evaluation. J Appl Polym Sci 2011. [DOI: 10.1002/app.34228] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Ex Vivo Protein Deposition on Bi-Weekly Silicone Hydrogel Contact Lenses. Optom Vis Sci 2010. [DOI: 10.1097/opx.0b013e3181ce0681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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