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Kavitha S, Tejaswini SU, Venkatesh R, Zebardast N. Wound modulation in glaucoma surgery: The role of anti-scarring agents. Indian J Ophthalmol 2024; 72:320-327. [PMID: 38153968 PMCID: PMC11001230 DOI: 10.4103/ijo.ijo_2013_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/18/2023] [Accepted: 10/16/2023] [Indexed: 12/30/2023] Open
Abstract
Filtration surgery is one of the most frequently performed surgeries in the management of glaucoma, and trabeculectomy is considered the gold standard surgical technique for the same. Though trabeculectomy has been reported to have an excellent initial success rate, about 30% of them fail in 3 years, and nearly 50% of them fail in 5 years. The most significant risk of failure still seems to be wound scarring, especially episcleral fibrosis, leading to bleb failure. As a result, it is essential to explore the role of anti-scarring agents, including mitomycin C, and 5-fluorouracil in wound modulation and improving the bleb survival rate. Since these agents are widely used in trabeculectomy, it is crucial to understand the various modes of application, advantages, and adverse effects of these agents. On an evidence-based approach, all these points have been highlighted in this review article. In addition, the newer agents available for wound modulation and their scope for practical application are discussed.
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Affiliation(s)
| | | | | | - Nazlee Zebardast
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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2
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Fajstavr D, Fajstavrová K, Frýdlová B, Slepičková Kasálková N, Švorčík V, Slepička P. Biopolymer Honeycomb Microstructures: A Review. MATERIALS (BASEL, SWITZERLAND) 2023; 16:772. [PMID: 36676507 PMCID: PMC9863042 DOI: 10.3390/ma16020772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/07/2023] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
In this review, we present a comprehensive summary of the formation of honeycomb microstructures and their applications, which include tissue engineering, antibacterial materials, replication processes or sensors. The history of the honeycomb pattern, the first experiments, which mostly involved the breath figure procedure and the improved phase separation, the most recent approach to honeycomb pattern formation, are described in detail. Subsequent surface modifications of the pattern, which involve physical and chemical modifications and further enhancement of the surface properties, are also introduced. Different aspects influencing the polymer formation, such as the substrate influence, a particular polymer or solvent, which may significantly contribute to pattern formation, and thus influence the target structural properties, are also discussed.
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3
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Sonntag SR, Gniesmer S, Gapeeva A, Offermann KJ, Adelung R, Mishra YK, Cojocaru A, Kaps S, Grisanti S, Grisanti S, Tura A. In Vitro Evaluation of Zinc Oxide Tetrapods as a New Material Component for Glaucoma Implants. Life (Basel) 2022; 12:1805. [PMID: 36362958 PMCID: PMC9697987 DOI: 10.3390/life12111805] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/03/2022] [Accepted: 11/05/2022] [Indexed: 09/09/2024] Open
Abstract
In our previous study we were able to show that zinc oxide (ZnO) tetrapods inhibit wound healing processes. Therefore, the aim of this study was to test the antiproliferative effect of two types of porous polydimethylsiloxane (PDMS)/ tetrapodal zinc oxide (ZnO-T) materials, as well as their usability for glaucoma implants. To find the best implant material, two different porous PDMS/ZnO-T materials were examined. One consisted of 3D interconnected PDMS coarse-pored foams with protruding ZnO-T particles; the other consisted of fine-pored 3D interconnected ZnO-T networks homogeneously coated by a thin PDMS film in the nanometer range. Fibroblast cell viability was investigated for both materials via MTT dye, and some implant material samples were further processed for electron microscopy. Both PDMS/ZnO-T materials showed reduced cell viability in the MTT staining. Furthermore, the electron microscopy revealed barely any fibroblasts growing on the implant materials. At the surface of the fine-pored implant material, however, fibroblasts could not be observed in the etched control samples without ZnO-T. It was found that post-processing of the material to the final stent diameter was highly challenging and that the fabrication method, therefore, had to be adapted. In conclusion, we were able to demonstrate the antiproliferative potential of the two different PDMS/ZnO-T materials. Furthermore, smaller pore size (in the range of tens of micrometers) in the implant material seems to be preferable.
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Affiliation(s)
| | - Stefanie Gniesmer
- Department of Ophthalmology, University of Luebeck, 23538 Luebeck, Germany
| | - Anna Gapeeva
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Klaus Jakob Offermann
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Rainer Adelung
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Yogendra Kumar Mishra
- Mads Clausen Institute, NanoSYD, University of Southern Denmark, 6400 Sønderborg, Denmark
| | - Ala Cojocaru
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
- Phi-Stone AG, 24143 Kiel, Germany
| | - Sören Kaps
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Swaantje Grisanti
- Department of Ophthalmology, University of Luebeck, 23538 Luebeck, Germany
| | - Salvatore Grisanti
- Department of Ophthalmology, University of Luebeck, 23538 Luebeck, Germany
| | - Aysegül Tura
- Department of Ophthalmology, University of Luebeck, 23538 Luebeck, Germany
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4
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Sonntag SR, Gniesmer S, Gapeeva A, Adelung R, Cojocaru A, Mishra YK, Kaps S, Tura A, Grisanti S, Grisanti S, Nassar K. Zinc Oxide Tetrapods Modulate Wound Healing and Cytokine Release In Vitro-A New Antiproliferative Substance in Glaucoma Filtering Surgery. Life (Basel) 2022; 12:1691. [PMID: 36362846 PMCID: PMC9692309 DOI: 10.3390/life12111691] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/14/2022] [Accepted: 10/19/2022] [Indexed: 09/09/2024] Open
Abstract
Glaucoma filtering surgery is applied to reduce intraocular pressure (IOP) in cases of uncontrolled glaucoma. However, postoperative fibrosis reduces the long-term success of both standard trabeculectomy and microstents. The aim of this study was to test the antiproliferative and anti-inflammatory potential of ZnO-tetrapods (ZnO-T) on human Tenon's fibroblasts (HTFs) for glaucoma surgery. The toxicity of ZnO-T on HTFs was determined using an MTT test. For analysis of fibroblast proliferation, migration, and transdifferentiation, cultures were stained for Ki67, alpha-smooth muscle actin (α-SMA), and p-SMAD. A fully quantitative multiplex ELISA was used to determine the concentrations of different cytokines, platelet-derived growth factor (PDGF), and hepatocyte growth factor (HGF) in culture supernatants with and without previous ZnO-T treatment. Treatment with higher concentrations (10 and 20 µg/mL) was associated with HTF toxicity, as shown in the wound healing assay. Furthermore, the number of Ki67, α-SMA-positive, and pSMAD-positive cells, as well as IL-6 and HGF in supernatants, were significantly reduced following incubation with ZnO-T. In conclusion, we were able to show the antiproliferative and anti-inflammatory potentials of ZnO-T. Therefore, the use of ZnO-T may provide a new approach to reducing postoperative fibrosis in glaucoma filtering surgery.
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Affiliation(s)
| | - Stefanie Gniesmer
- Department of Ophthalmology, University of Lübeck, 23538 Lubeck, Germany
| | - Anna Gapeeva
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Rainer Adelung
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Ala Cojocaru
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
- Phi-Stone AG, 24143 Kiel, Germany
| | - Yogendra Kumar Mishra
- Mads Clausen Institute, NanoSYD, University of Southern Denmark, 6400 Sonderborg, Denmark
| | - Sören Kaps
- Institute for Materials Science, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany
| | - Aysegül Tura
- Department of Ophthalmology, University of Lübeck, 23538 Lubeck, Germany
| | - Swaantje Grisanti
- Department of Ophthalmology, University of Lübeck, 23538 Lubeck, Germany
| | - Salvatore Grisanti
- Department of Ophthalmology, University of Lübeck, 23538 Lubeck, Germany
| | - Khaled Nassar
- Department of Ophthalmology, University of Lübeck, 23538 Lubeck, Germany
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5
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Nishimura S, Murakami Y. Facile preparation of porous polymeric sheets with different sizes of pores on both sides using spontaneous emulsification. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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6
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Wolters JEJ, van Mechelen RJS, Al Majidi R, Pinchuk L, Webers CAB, Beckers HJM, Gorgels TGMF. History, presence, and future of mitomycin C in glaucoma filtration surgery. Curr Opin Ophthalmol 2021; 32:148-159. [PMID: 33315724 DOI: 10.1097/icu.0000000000000729] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Mitomycin C (MMC) is an alkylating agent with extraordinary ability to crosslink DNA, preventing DNA synthesis. By this virtue, MMC is an important antitumor drug. In addition, MMC has become the gold standard medication for glaucoma filtration surgery (GFS). This eye surgery creates a passage for drainage of aqueous humor (AqH) out of the eye into the sub-Tenon's space with the aim of lowering the intraocular pressure. A major cause of failure of this operation is fibrosis and scarring in the sub-Tenon's space, which will restrict AqH outflow. Intraoperative application of MMC during GFS has increased GFS success rate, presumably mainly by reducing fibrosis after GFS. However, still 10% of glaucoma surgeries fail within the first year. RECENT FINDINGS In this review, we evaluate risks and benefits of MMC as an adjuvant for GFS. In addition, we discuss possible improvements of its use by adjusting dose and method of administration. SUMMARY One way of improving GFS outcome is to prolong MMC delivery by using a drug delivery system.
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Affiliation(s)
- Jarno E J Wolters
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Ralph J S van Mechelen
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Rana Al Majidi
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
- School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Leonard Pinchuk
- InnFocus, Inc., a Santen Company
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Carroll A B Webers
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
| | - Henny J M Beckers
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
| | - Theo G M F Gorgels
- University Eye Clinic Maastricht, Maastricht University Medical Centre + (MUMC+), Maastricht
- Chemelot Institute for Science and Technology (InSciTe), Geleen
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Rahić O, Tucak A, Omerović N, Sirbubalo M, Hindija L, Hadžiabdić J, Vranić E. Novel Drug Delivery Systems Fighting Glaucoma: Formulation Obstacles and Solutions. Pharmaceutics 2020; 13:E28. [PMID: 33375224 PMCID: PMC7824381 DOI: 10.3390/pharmaceutics13010028] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/19/2020] [Accepted: 12/22/2020] [Indexed: 02/06/2023] Open
Abstract
Glaucoma is considered to be one of the biggest health problems in the world. It is the main cause of preventable blindness due to its asymptomatic nature in the early stages on the one hand and patients' non-adherence on the other. There are several approaches in glaucoma treatment, whereby this has to be individually designed for each patient. The first-line treatment is medication therapy. However, taking into account numerous disadvantages of conventional ophthalmic dosage forms, intensive work has been carried out on the development of novel drug delivery systems for glaucoma. This review aims to provide an overview of formulation solutions and strategies in the development of in situ gel systems, nanosystems, ocular inserts, contact lenses, collagen corneal shields, ocular implants, microneedles, and iontophoretic devices. The results of studies confirming the effectiveness of the aforementioned drug delivery systems were also briefly presented.
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Affiliation(s)
- Ognjenka Rahić
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
| | - Amina Tucak
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
| | - Naida Omerović
- Department of Clinical Pharmacy, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina;
| | - Merima Sirbubalo
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
| | - Lamija Hindija
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
| | - Jasmina Hadžiabdić
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
| | - Edina Vranić
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Sarajevo, Zmaja od Bosne 8, 71000 Sarajevo, Bosnia and Herzegovina; (A.T.); (M.S.); (L.H.); (J.H.)
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8
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Miller PE, Eaton JS. Medical anti-glaucoma therapy: Beyond the drop. Vet Ophthalmol 2020; 24 Suppl 1:2-15. [PMID: 33164328 DOI: 10.1111/vop.12843] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/30/2020] [Accepted: 10/20/2020] [Indexed: 12/25/2022]
Abstract
Barriers to effective medical therapy are numerous and include difficulties with effective and sustained control of intraocular pressure (IOP) and adherence to prescribed anti-glaucoma drop regimens. In an effort to circumvent these challenges, a number of new anti-glaucoma therapies with sustained effects have emerged. Methods for sustained delivery of prostaglandin analogs are being intensely investigated and many are in human clinical trials. Intracameral devices include the following: Allergan's Durysta™ Bimatoprost SR, Envisia Therapeutics' ENV515 travoprost implant, Glaukos' iDose™ , Ocular Therapeutix's OTX-TIC travoprost implant, and Santen's polycaprolactone implant with PGE2-derivative DE-117. Other prostaglandin-based technologies include Allergan's bimatoprost ring (placed in the conjunctival fornix), Ocular Therapeutics' OTX-TP intracanalicular travoprost implant, subconjunctival latanoprost in a liposomal formulation, and the PGE2 derivative PGN 9856-isopropyl ester that is applied to the periorbital skin. Exciting breakthroughs in gene therapy include using viral vectors to correct defective genes such as MYOC or to modulate gonioimplant fibrosis, CRISPR technology to edit MYOC or to alter aquaporin to reduce aqueous humor production, and siRNA technology to silence specific genes. Stem cell technology can repopulate depleted tissues or, in the case of Neurotech's Renexus® NT-501 intravitreal implant, serve as a living drug delivery device that continuously secretes neurotrophic factors. Other unique approaches involve nanotechnology, nasal sprays that deliver drug directly to the optic nerve and noninvasive alternating current stimulation of surviving cells in the optic nerve. Over time these modalities are likely to challenge the preeminent role that drops currently play in the medical treatment of glaucoma in animals.
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Affiliation(s)
- Paul E Miller
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Joshua Seth Eaton
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA
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9
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Kwon S, Kim SH, Khang D, Lee JY. Potential Therapeutic Usage of Nanomedicine for Glaucoma Treatment. Int J Nanomedicine 2020; 15:5745-5765. [PMID: 32821099 PMCID: PMC7418176 DOI: 10.2147/ijn.s254792] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/05/2020] [Indexed: 12/20/2022] Open
Abstract
Glaucoma is a group of diseases characterized by progressive degeneration of retinal ganglion cells, leading to irreversible blindness. Currently, intraocular pressure reduction is the only established treatment available for glaucoma. With this treatment, the progression of the disease can only be delayed and there is no recovery. In addition, the commercially available eye drops have the disadvantage of low compliance and short therapeutic time, while glaucoma surgery always has the risk of failure due to wound fibrosis. Nanotechnology can overcome the limitations of the current treatment through the encapsulation and conjugation of drugs used for lowering intraocular pressure and antifibrotic agents using biodegradable or biocompatible nanoparticles for the sustained release of the drugs to protect the damaged ocular cells. Furthermore, using nanotechnology, treatment can be administered in various forms, including eye drops, contact lens, and ocular inserts, according to the convenience of the patients. Despite the promising results of delaying the progression of glaucoma, the regeneration of damaged ocular cells, including trabecular meshwork and retinal ganglion cells, is another critical hurdle to overcome. Bone marrow-derived mesenchymal stem cells and Müller glia cells can secrete neurogenic factors that trigger the regeneration of associated cells, including trabecular meshwork and retinal ganglion cells. In conclusion, this review highlights the potential therapeutic applications of nanotechnology- and stem cell-based methods that can be employed for the protection and regeneration of ocular cells.
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Affiliation(s)
- Song Kwon
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, South Korea
| | - Sung Hyun Kim
- Department of Ophthalmology, Gil Medical Center, Gachon University, College of Medicine, Incheon 21565, South Korea
| | - Dongwoo Khang
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, South Korea.,Department of Gachon Advanced Institute for Health Science & Technology (GAIHST), Gachon University, Incheon 21999, South Korea.,Department of Physiology, School of Medicine, Gachon University, Incheon 21999, South Korea
| | - Jong Yeon Lee
- Department of Ophthalmology, Gil Medical Center, Gachon University, College of Medicine, Incheon 21565, South Korea
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10
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Suner SS, Sahiner N. Biocompatible macro, micro and nano scale guar gum hydrogels and their protein absorption capacity. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2020. [DOI: 10.1080/10601325.2020.1787844] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Selin Sagbas Suner
- Chemistry Department, Faculty of Science & Arts, and Nanoscience and Technology Research and Application Center (NANORAC), Canakkale Onsekiz Mart University, Canakkale, Turkey
| | - Nurettin Sahiner
- Chemistry Department, Faculty of Science & Arts, and Nanoscience and Technology Research and Application Center (NANORAC), Canakkale Onsekiz Mart University, Canakkale, Turkey
- Department of Ophthalmology, School of Medicine, University of South Florida Eye Institute, Tampa, FL, USA
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Fischer NA, Kahook MY, Abdullah S, Porteous E, Ammar DA, Patnaik JL, SooHoo JR. Effect of Novel Design Modifications on Fibrotic Encapsulation: An In Vivo Glaucoma Drainage Device Study in a Rabbit Model. Ophthalmol Ther 2020; 9:279-291. [PMID: 32152939 PMCID: PMC7196114 DOI: 10.1007/s40123-020-00242-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To quantify the effects of modified Ahmed glaucoma valves® (AGV) with anti-fibrotic plate coatings or a plate surface micro-pattern on outflow resistance and tissue response. Methods Twelve New Zealand rabbits were divided into four groups: commercially available AGV implants (n = 3), AGV with hydrophilic coating (n = 3), AGV with heparin coating (n = 3), and AGV with a plate surface micro-pattern (n = 3). After 6 weeks, the anterior chamber silicone tube was cannulated in situ and perfused with 2.5 μL/min of saline. The pressures were recorded with a perfusion system to measure outflow resistance. The rabbits were then euthanized followed by enucleation of all eyes for bleb histological analyses. Results Hydrostatic pressures were significantly lower in AGVs with the hydrophilic plate coating (mean difference −9.6 mm Hg; p < 0.001), heparin-coated plates (mean difference −4.4 mm Hg; p < 0.001), and micro-patterned plates (mean difference −18.6 mm Hg, p < 0.001), indicating lower outflow resistance compared to control AGV models. Fibrotic encapsulation was lower in hydrophilic plate coating (84.2 μm; mean difference −6.2 μm, p = 0.425), micro-patterned surface (63.7 μm; mean difference −26.7 μm, p = 0.003), and heparin plate coating (49.3 μm; mean difference −41.1 μm, p = 0.006) when compared to control AGV models. Conclusions Modified AGVs with plate coatings and AGVs with micro-patterned plates both appear to reduce postoperative fibrotic encapsulation and aqueous outflow resistance by altering the tissue response to implanted materials. Further studies are needed to characterize the safety and role of plate surface modifications on glaucoma drainage devices.
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Affiliation(s)
- Nathan A Fischer
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Malik Y Kahook
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO, USA
| | | | | | - David A Ammar
- Lions Eye Institute for Transplant and Research, Tampa, FL, USA
| | - Jennifer L Patnaik
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Jeffrey R SooHoo
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO, USA.
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12
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Antimicrobial activity and biocompatibility of slow-release hyaluronic acid-antibiotic conjugated particles. Int J Pharm 2020; 576:119024. [PMID: 31926974 DOI: 10.1016/j.ijpharm.2020.119024] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/20/2019] [Accepted: 01/06/2020] [Indexed: 12/14/2022]
Abstract
Here, the aim was to design and use a long-lasting antibiotic release system for prevention of postoperative infections in ophthalmic surgery. Ciprofloxacin and vancomycin-conjugated hyaluronic acid (HA) particles were prepared as drug carriers for sustained release of antibiotics. The antimicrobial effects of the released drugs were determined by disc-diffusion and macro-dilution tests at different times up to 2 weeks. Slow degradable HA particles were obtained with 35.2 wt% degradation within 21 days. The drug loading amount was increased by employing two sequential chemical linking (conjugation, 2C) and one physical absorption loading (A) procedures (2C + A processes) from 148 ± 8 to 355 ± 11 mg/g HA particles for vancomycin. The amounts of vancomycin and ciprofloxacin that were released linearly was estimated as 64.35 ± 7.35 and 25.00 ± 0.68 mg/g, respectively, from drug-conjugated HA particles in 100 h. Antimicrobial studies revealed that antibiotic-conjugated HA particles could inhibit the growth of microorganisms from 1 h to 1 week. The MBC values were measured as 0.25, 4.0, and 0.25 mg/mL against Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis, respectively, after 72 h incubation time. Cytotoxicity studies showed no difference between fibroblast growth or corneal thickness after 5 days with or without HA-antibiotic particles. The drug release studies and antimicrobial activity of antibiotic-loaded HA particles with time against various bacteria further revealed that HA particles are very effective in preventing bacterial infections. Likewise, cytotoxicity studies suggest that these particles pose no toxicity to eukaryotic cells, including corneal endothelium.
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Abstract
Glaucoma is the second leading cause of blindness worldwide. Even though significant advances have been made in its management, currently available antiglaucoma therapies suffer from considerable drawbacks. Typically, the success and efficacy of glaucoma medications are undermined by their limited bioavailability to target tissues and the inadequate adherence demonstrated by patients with glaucoma. The latter is due to a gradual decrease in tolerability of lifelong topical therapies and the significant burden to patients of prescribed stepwise antiglaucoma regimens with frequent dosing which impact quality of life. On the other hand, glaucoma surgery is restricted by the inability of antifibrotic agents to efficiently control the wound healing process without causing severe collateral damage and long-term complications. Evolution of the treatment paradigm for patients with glaucoma will ideally include prevention of retinal ganglion cell degeneration by the successful delivery of neurotrophic factors, anti-inflammatory drugs, and gene therapies. Nanotechnology-based treatments may surpass the limitations of currently available glaucoma therapies through optimized targeted drug delivery, increased bioavailability, and controlled release. This review addresses the recent advances in glaucoma treatment strategies employing nanotechnology, including medical and surgical management, neuroregeneration, and neuroprotection.
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14
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Juliana FR, Kesse S, Boakye-Yiadom KO, Veroniaina H, Wang H, Sun M. Promising Approach in the Treatment of Glaucoma Using Nanotechnology and Nanomedicine-Based Systems. Molecules 2019; 24:E3805. [PMID: 31652593 PMCID: PMC6833088 DOI: 10.3390/molecules24203805] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/17/2019] [Accepted: 10/19/2019] [Indexed: 12/14/2022] Open
Abstract
Glaucoma is considered a leading cause of blindness with the human eye being one of the body's most delicate organs. Ocular diseases encompass diverse diseases affecting the anterior and posterior ocular sections, respectively. The human eye's peculiar and exclusive anatomy and physiology continue to pose a significant obstacle to researchers and pharmacologists in the provision of efficient drug delivery. Though several traditional invasive and noninvasive eye therapies exist, including implants, eye drops, and injections, there are still significant complications that arise which may either be their low bioavailability or the grave ocular adverse effects experienced thereafter. On the other hand, new nanoscience technology and nanotechnology serve as a novel approach in ocular disease treatment. In order to interact specifically with ocular tissues and overcome ocular challenges, numerous active molecules have been modified to react with nanocarriers. In the general population of glaucoma patients, disease growth and advancement cannot be contained by decreasing intraocular pressure (IOP), hence a spiking in future research for novel drug delivery systems and target therapeutics. This review focuses on nanotechnology and its therapeutic and diagnostic prospects in ophthalmology, specifically glaucoma. Nanotechnology and nanomedicine history, the human eye anatomy, research frontiers in nanomedicine and nanotechnology, its imaging modal quality, diagnostic and surgical approach, and its possible application in glaucoma will all be further explored below. Particular focus will be on the efficiency and safety of this new therapy and its advances.
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Affiliation(s)
| | - Samuel Kesse
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
- Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
| | - Kofi Oti Boakye-Yiadom
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
- Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
| | - Hanitrarimalala Veroniaina
- State Key Laboratory of Modern Chinese Medicine, China Pharmaceutical University, Nanjing 210009, China.
| | - Huihui Wang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China.
| | - Meihao Sun
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China.
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15
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Sahiner M, Blake DA, Fullerton ML, Suner SS, Sunol AK, Sahiner N. Enhancement of biocompatibility and carbohydrate absorption control potential of rosmarinic acid through crosslinking into microparticles. Int J Biol Macromol 2019; 137:836-843. [PMID: 31284004 DOI: 10.1016/j.ijbiomac.2019.07.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/28/2019] [Accepted: 07/04/2019] [Indexed: 11/24/2022]
Abstract
Rosmarinic acid (RA), a bioflavonoid and antioxidant that exists in plants of the Lamiaceae family, was crosslinked into particles as poly(Rosmarinic Acid) (p(RA)) via an emulsion crosslinking method. The particles were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, solid state nuclear magnetic resonance 13C NMR spectroscopy, and thermal gravimetric analysis. The zeta potential values of p(RA) particles were determined at different pHs; the isoelectric point was estimated as pH 1.2. The release of monomeric RA from the particles at 37.5 °C was found to be similar at different pHs, 1.0, 7.4, and 11.0. The effects of p(RA) on hemolysis and coagulation were found to be minimal. The antioxidant activity of p(RA) particles and RA monomer were almost indistinguishable suggesting that p(RA) particles may be used as an antioxidant. On a per weight basis, p(RA) particles were ~66% less cytotoxic to mammalian cells that RA monomer, as assessed using COS-1 cells. In addition, p(RA) was an 8.6-fold stronger inhibitor of α-glycosidase than RA; the IC50s of the monomer and particles were 0.121 and 0.014 mg/mL, respectively. The strong inhibitory effect of p(RA) on α-glycosidase, coupled with its reduced cytotoxicity and antioxidant activity, provide new opportunities for the use of p(RA).
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Affiliation(s)
- Mehtap Sahiner
- Fashion Design, Canakkale Applied Science, Canakkale Onsekiz Mart University, Canakkale, Turkey
| | - Diane A Blake
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70448, USA.
| | - Mitchell L Fullerton
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70448, USA; Bioinnovation PhD Program, 605 Lindy Boggs Bldg, New Orleans, LA 70118, United States of America
| | - Selin S Suner
- Nanoscience and Technology Research and Application Center (NANORAC), Faculty of Science and Arts, Department of Chemistry, Turkey; Canakkale Onsekiz Mart University, Terzioglu Campus, 17100, Canakkale, Turkey
| | - Aydin K Sunol
- Department of Chemical and Biomolecular Engineering, University of South Florida, Tampa, FL, 33620, USA
| | - Nurettin Sahiner
- Nanoscience and Technology Research and Application Center (NANORAC), Faculty of Science and Arts, Department of Chemistry, Turkey; Canakkale Onsekiz Mart University, Terzioglu Campus, 17100, Canakkale, Turkey; Department of Chemical and Biomolecular Engineering, University of South Florida, Tampa, FL, 33620, USA; Department of Ophthalmology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd, MDC 21, Tampa, FL 33612, USA.
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16
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Dong A, Han L, Shao Z, Fan P, Zhou X, Yuan H. Glaucoma Drainage Device Coated with Mitomycin C Loaded Opal Shale Microparticles to Inhibit Bleb Fibrosis. ACS APPLIED MATERIALS & INTERFACES 2019; 11:10244-10253. [PMID: 30689341 DOI: 10.1021/acsami.8b18551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Excessive fibrosis is the topmost factor for the defeat of surgical glaucoma drainage device (GDD) implantation. Adjuvant drug approaches are promising to help reduce the scar formation and excessive fibrosis. Opal shale (OS), as a natural state and noncrystalline silica substance with poriferous nature and strong adsorbability, is highly likely to undertake drug loading and delivery. Here, we employed OS microparticles (MPs) by ultrasound and centrifugation and presented an innovative and improved GDD coated with OS MPs, which were loaded with mitomycin C (MMC). MMC-loaded OS MPs were physically absorbed on the Ahmed glaucoma valve surface through OS' adsorbability. About 5.51 μg of MMC was loaded on the modified Ahmed glaucoma valve and can be released for 18 days in vitro. MMC-loaded OS MPs inhibited fibroblast proliferation and showed low toxicity to primary Tenon's fibroblasts. The ameliorated drainage device was well tolerated and effective in reducing the fibrous reaction in vivo. Hence, our study constructed an improved Ahmed glaucoma valve using OS MPs without disturbing aqueous humor drainage pattern over the valve surface. The modified Ahmed glaucoma valve successfully alleviated scar tissue formation after GDD implantation surgery.
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Affiliation(s)
- Aimeng Dong
- Department of Ophthalmology , The Second Affiliated Hospital of Harbin Medical University , Harbin , Heilongjiang 150081 , P. R. China
- The Key Laboratory of Myocardial Ischemia , Harbin Medical University, Ministry of Education , Harbin , Heilongjiang Province 150081 , P. R. China
| | - Liang Han
- Department of Pharmaceutics, College of Pharmaceutical Sciences , Soochow University , Suzhou 215123 , P. R. China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences , Soochow University , Suzhou 215123 , P. R. China
| | - Zhengbo Shao
- Department of Ophthalmology , The Second Affiliated Hospital of Harbin Medical University , Harbin , Heilongjiang 150081 , P. R. China
| | - Pan Fan
- Department of Ophthalmology , The Second Affiliated Hospital of Harbin Medical University , Harbin , Heilongjiang 150081 , P. R. China
| | - Xinrong Zhou
- Department of Ophthalmology , The Second Affiliated Hospital of Harbin Medical University , Harbin , Heilongjiang 150081 , P. R. China
| | - Huiping Yuan
- Department of Ophthalmology , The Second Affiliated Hospital of Harbin Medical University , Harbin , Heilongjiang 150081 , P. R. China
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17
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Effect of 2 Novel Sustained-release Drug Release Systems on Bleb Fibrosis: An In Vivo Trabeculectomy Study in a Rabbit Model. J Glaucoma 2019; 28:512-518. [PMID: 30807440 DOI: 10.1097/ijg.0000000000001215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PRECIS Rabbit model studies suggested better morphology blebs with equal intraocular pressure (IOP) efficacy as a standard mitomycin C (MMC) trabeculectomy using a novel slow-release drug delivery antifibrotic system delivering small quantities of MMC and 5-fluorouracil (5-FU). PURPOSE To evaluate 2 different concentrations of biodegradable poly(lactic-co-glycolic acid) (PLGA) system with 5-FU and MMC (ElutiGLASS) for their ability to reduce fibrosis and compare the results with standard trabeculectomy with MMC in a rabbit model. MATERIALS AND METHODS New Zealand albino rabbits (19) were divided into 3 groups (A, B, C) and standard trabeculectomy operation was performed in the right eye of each rabbit.Group (A) had trabeculectomy with MMC (0.4 mg/mL) applied using a Weck cell sponge; (B) trabeculectomy with slow-release ElutiGLASS (0.23 mg, 5-FU/0.33 μg MMC released over 23 to 30 d); (C) trabeculectomy with rapid release ElutiGLASS (0.45 mg of 5-FU/0.65 μg MMC, released over 5 to 7 d). The rabbits were followed for 3 months before euthanasia. RESULTS Bleb morphology, vascularity, and fibrosis were less pronounced in groups B and C when compared with group A at 3 months. Group B appears to have a lower and more diffuse bleb appearance compared with the other 2 groups with honeycomb appearance on both clinical examination and ultrasound biomicroscopy imaging with higher percentage of maintained bleb space (83%), less fibrosis than group A while maintaining the same low inflammation score as the other 2 groups on histology. At 3 months, the PLGA polymer had completely disappeared in all rabbits. There were no statistical differences in the degree of IOP reduction or histologic inflammation, among the 3 groups. CONCLUSIONS We successfully created a sustained-release antifibrotic drug delivery system that delivered known dosage of the drugs at doses that are significantly lower than the current standard, and resulted in less fibrosis while maintaining a healthy bleb and equal reduction of IOP. TRANSLATIONAL RELEVANCE These results are supportive of the antifibrotic effect of the slow-release drug delivery system used in conjunction with trabeculectomy, thus paving the way for human pilot studies to improve and simplify existing surgical techniques for filtering surgeries in glaucoma.
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Cardigos J, Ferreira Q, Crisóstomo S, Moura-Coelho N, Cunha JP, Pinto LA, Ferreira JT. Nanotechnology-Ocular Devices for Glaucoma Treatment: A Literature Review. Curr Eye Res 2018; 44:111-117. [PMID: 30309248 DOI: 10.1080/02713683.2018.1536218] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Nanotechnology enabled the development of materials and devices with great utility in different fields of medicine. By using engineered-based nano-devices and structures, human biological systems may be controlled and repaired at a molecular scale, ultimately leading to a biological benefit. In particular, in the field of glaucoma treatment, nanotechnology may, for example, enhance drug residence time on the ocular surface and ocular bioavailability, as well as improve surgical success by both optimizing postoperative scarring and providing a wider safety window. Further studies are still needed to entirely explain the pharmacodynamics of nanotechnology-based therapeutic approaches and prove their biological consequences in human eyes. This review aims to summarize the literature concerning the advances in nanotechnology, specifically regarding ocular devices applied to the treatment of glaucoma.
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Affiliation(s)
- Joana Cardigos
- a Departamento de Oftalmologia , Centro Hospitalar Lisboa Central , Lisboa , Portugal
| | | | - Sara Crisóstomo
- a Departamento de Oftalmologia , Centro Hospitalar Lisboa Central , Lisboa , Portugal
| | - Nuno Moura-Coelho
- a Departamento de Oftalmologia , Centro Hospitalar Lisboa Central , Lisboa , Portugal
| | - João Paulo Cunha
- a Departamento de Oftalmologia , Centro Hospitalar Lisboa Central , Lisboa , Portugal.,c NOVA Medical School/Faculdade de Ciências Médicas da Universidade Nova de Lisboa , Lisboa , Portugal
| | - Luís Abegão Pinto
- d Departamento de Oftalmologia , Centro Hospitalar Lisboa Norte , Lisboa , Portugal.,e Centro de Estudos das Ciências da Visão , Faculdade de Medicina da Universidade de Lisboa , Lisboa , Portugal
| | - Joana Tavares Ferreira
- a Departamento de Oftalmologia , Centro Hospitalar Lisboa Central , Lisboa , Portugal.,c NOVA Medical School/Faculdade de Ciências Médicas da Universidade Nova de Lisboa , Lisboa , Portugal
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19
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Sahiner N, Sagbas S, Sahiner M, Blake DA, Reed WF. Polydopamine particles as nontoxic, blood compatible, antioxidant and drug delivery materials. Colloids Surf B Biointerfaces 2018; 172:618-626. [PMID: 30223244 DOI: 10.1016/j.colsurfb.2018.09.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/05/2018] [Accepted: 09/09/2018] [Indexed: 01/09/2023]
Abstract
Herein, the potential biomedical application of poly(3,4-dihyroxyphenyl)ethylamine, (poly(dopamine)-p(DA)) particles is reported. P(DA) particles with the size about 100 nm, 18.05 m2/g specific surface area, and mesoporous structure (7.19 nm pore width) were prepared and shown to be chemically modifiable using chlorosulfonic acid (CSA) and 3-CHloro-2 hydroxypropyl) trimethylammonium chloride solution (CHPACl) to obtain sulfonic acid and quaternary amine group containing modified p(DA) particles, m-p(DA)-CSA and m-p(DA)-CHPACl particles, respectively. The hydrolytic degradation of p(DA) particles at different pHs, including 1, 7.4 and 11, was carried out at 37.5 °C. These degradation studies revealed that p(DA) is slightly degradable at pH 1 and pH 7.4 with weight losses of 13.01 ± 0.08% and 7.26 ± 0.23% in 11 days, respectively. At pH 11, a sustained degradation that is almost linear degradation with time was observed for up to 30 days, with a total weight loss of 21.42 ± 0.88%. Furthermore, p(DA) particles were tested for cell toxicity against COS-1 cells and found non-toxic up to 50 μg/mL with 95.6 ± 4.5% cell viability as compared to 37.5 ± 0.03% for DA molecules. The p(DA) particles and DA were also compared for their ability to inhibit α-glucosidase; both inhibited α-glucosidase inhibition activity a concentration-dependent fashion: at concentrations of 500-4000 μg/mL, p(DA) provided 8.52-27.67% inhibition while DA inhibited 42.8-67.7% over the same concentration range. Furthermore, p(DA) particles were found to be blood compatible e.g., non-hemolytic with 1.87 ± 0.97% hemolysis ratio up to 50 μg/mL concentration and with 86.7% blood clotting index. Interestingly, p(DA) particle can be considered as an effective antioxidant with 33.5 ± 3.9 μg/ mL total phenol content in terms of gallic acid equivalency and 0.89 ± 0. 30 μmol/g trolox equivalent antioxidant capacity (TEAC). Finally, p(DA) particles and their modified forms, m-p(DA)-CSA, and m-p(DA)-CHPACl, were shown to be useful as active agent/drug delivery devices by using acyclovir as a model drug that can be readily loaded into particles and released at longer times at higher amounts for the modified p(DA) particles at physiological conditions.
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Affiliation(s)
- Nurettin Sahiner
- Department of Physics and Engineering Physics, Faculty of Science and Engineering Tulane University, 2001 Percival Stern Hall, New Orleans, LA, 70118, USA; Chemistry Department, Faculty of Science & Arts, and Nanoscience and Technology Research and Application Center (NANORAC), Canakkale Onsekiz Mart University, Terzioglu Campus, 17100, Canakkale, Turkey.
| | - Selin Sagbas
- Chemistry Department, Faculty of Science & Arts, and Nanoscience and Technology Research and Application Center (NANORAC), Canakkale Onsekiz Mart University, Terzioglu Campus, 17100, Canakkale, Turkey
| | - Mehtap Sahiner
- Department of Fashion Design, Canakkale Applied Sciences, Canakkale Onsekiz Mart University, Terzioglu Campus, 17100, Canakkale, Turkey
| | - Diane A Blake
- Department of Biochemistry & Molecular Biology, School of Medicine, Tulane University, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
| | - Wayne F Reed
- Department of Physics and Engineering Physics, Faculty of Science and Engineering Tulane University, 2001 Percival Stern Hall, New Orleans, LA, 70118, USA.
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20
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Calejo MT, Ilmarinen T, Skottman H, Kellomäki M. Breath figures in tissue engineering and drug delivery: State-of-the-art and future perspectives. Acta Biomater 2018; 66:44-66. [PMID: 29183847 DOI: 10.1016/j.actbio.2017.11.043] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 11/09/2017] [Accepted: 11/22/2017] [Indexed: 12/11/2022]
Abstract
The breath figure (BF) method is an easy, low-cost method to prepare films with a highly organized honeycomb-like porous surface. The particular surface topography and porous nature of these materials makes them valuable substrates for studying the complex effects of topography on cell fate, and to produce biomimetic materials with high performance in tissue engineering. Numerous researchers over the last two decades have studied the effects of the honeycomb topography on a variety of primary and immortalized cell lines, and drew important conclusions that can be translated to the construction of optimal biomaterials for cell culture. The literature also encouragingly shows the potential of honeycomb films to induce differentiation of stem cells down a specific lineage without the need for biochemical stimuli. Here, we review the main studies where BF honeycomb films are used as substrates for tissue engineering applications. Furthermore, we highlight the numerous advantages of the porous nature of the films, such as the enhanced, spatially controlled adsorption of proteins, the topographical cues influencing cellular behavior, and the enhanced permeability which is essential both in vitro and in vivo. Finally, this review highlights the elegant use of honeycomb films as drug-eluting biomaterials or as reservoirs for distinct drug delivery systems. STATEMENT OF SIGNIFICANCE Combining biocompatible surfaces and 3D nano/microscale topographies, such as pores or grooves, is an effective strategy for manufacturing tissue engineering scaffolds. The breath figure (BF) method is an easy technique to prepare cell culture substrates with an organized, honeycomb-like porous surface. These surface features make these scaffolds valuable for studying how the cells interact with the biomaterials. Their unique surface topography can also resemble the natural environment of the tissues in the human body. For that reason, numerous studies, using different cell types, have shown that honeycomb films can constitute high performance substrates for cell culture. Here, we review those studies, we highlight the advantages of honeycomb films in tissue engineering and we discuss their potential as unique drug-eluting systems.
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Affiliation(s)
- Maria Teresa Calejo
- BioMediTech Institute and Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, Tampere, Finland.
| | - Tanja Ilmarinen
- BioMediTech Institute and Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
| | - Heli Skottman
- BioMediTech Institute and Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
| | - Minna Kellomäki
- BioMediTech Institute and Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, Tampere, Finland; BioMediTech Institute and Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
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21
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Leelakanok N, Geary S, Salem A. Fabrication and Use of Poly(d,l-lactide-co-glycolide)-Based Formulations Designed for Modified Release of 5-Fluorouracil. J Pharm Sci 2017; 107:513-528. [PMID: 29045885 DOI: 10.1016/j.xphs.2017.10.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 10/03/2017] [Accepted: 10/06/2017] [Indexed: 12/14/2022]
Abstract
5-fluorouracil (5-FU) is a chemotherapeutic agent that has been used for the treatment of a variety of malignancies since its initial introduction to the clinic in 1957. Owing to its short biological half-life, multiple dosings are generally required to maintain effective 5-FU plasma concentrations throughout the therapeutic period. Clinical studies have shown that continuous 5-FU administration is generally superior to bolus injection as exhibited by lower toxicities and increased therapeutic efficacy. Optimal therapeutic efficacy, however, is often compromised by the limiting therapeutic index. Whilst oral formulations are also used, these suffer from the drawbacks of variable bioavailability and first-pass metabolism. As a result, sustained release formulations of 5-FU have been investigated in an effort to mimic the kinetics of continuous infusion particularly for situations where local delivery is considered appropriate. The biocompatible, biodegradable, and highly tunable synthetic polymer, poly(d,l-lactide-co-glycolide) (PLGA), is widely used as a vector for sustained drug delivery, however, issues such as insufficient loading and inappropriate burst release kinetics have dogged progress into the clinic for small hydrophilic drugs such as 5-FU. This review provides introductory information about the mechanism of action, pharmacokinetic and physicochemical properties, and clinical use of 5-FU that have contributed to the development of PLGA-based 5-FU release platforms. In addition, this review provides information on fabrication methods used for a range of 5-FU-loaded PLGA formulations and discusses factors affecting the release kinetics of 5-FU as well as the in vitro and in vivo antitumor or antiproliferative efficacy of these platforms.
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Affiliation(s)
- Nattawut Leelakanok
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, Iowa City, Iowa 52242
| | - Sean Geary
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, Iowa City, Iowa 52242
| | - Aliasger Salem
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, Iowa City, Iowa 52242.
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22
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Arora JS, Cremaldi JC, Holleran MK, Ponnusamy T, Sunkara B, He J, Pesika NS, John VT. Hierarchical patterning of hydrogels by replica molding of impregnated breath figures leads to superoleophobicity. NANOSCALE 2016; 8:18446-18453. [PMID: 27775743 DOI: 10.1039/c6nr06629a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The surface chemistry and topography govern the spreading of liquids on a solid. When an oil drop makes a contact angle, θ > 90° on a solid surface, the solid is termed as oleophobic. Adding roughness to an inherently oleophobic surface enhances its oil dewetting and can lead to superoleophobicity when θ > 150°. In this study, we introduce the concept of a two-tier hierarchical roughness on the surface of soft materials such as hydrogels by forming the patterned inverse replica of breath figure polymer films impregnated with nanoparticles. The directed deposition of nanoparticles in the breath figure pores is accomplished by an aerosol assisted technique that exclusively leads to deposition within the pores and filling of the pores. The inverse replica of such impregnated films exhibits a close packed hexagonally structured second tier of surface roughness which directly leads to a superoleophobic surface. Since these structures have well defined geometries, it is possible to estimate the contact angle by assuming a partial wetting of the oil drop in a 'fakir' state on the rough surface. The estimation is in good agreement with the experimental contact angle value. While the work demonstrates a facile method to impart superoleophobicity to a hydrogel surface, it also demonstrates new methods to imbue breath figure pores with functional materials that can be easily transferred to the pores of the inverse replica.
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Affiliation(s)
- J S Arora
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA. and Vector Borne Infectious Diseases Research Center, Tulane University, New Orleans, LA 70112, USA
| | - J C Cremaldi
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
| | - M K Holleran
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
| | - T Ponnusamy
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
| | - B Sunkara
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
| | - J He
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
| | - N S Pesika
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA. and Vector Borne Infectious Diseases Research Center, Tulane University, New Orleans, LA 70112, USA
| | - V T John
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA. and Vector Borne Infectious Diseases Research Center, Tulane University, New Orleans, LA 70112, USA
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Adjunctive triamcinolone acetonide for Ahmed glaucoma valve implantation: a randomized clinical trial. Eur J Ophthalmol 2016; 27:411-416. [PMID: 27791254 DOI: 10.5301/ejo.5000892] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2016] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the effect of intraoperative sub-Tenon injection of triamcinolone acetonide (TA) as an adjunct to Ahmed glaucoma valve (AGV) implantation. METHODS In this triple-blind randomized clinical trial, 104 eyes with refractory glaucoma were randomly assigned to conventional AGV (non-TA group) or AGV with adjunctive triamcinolone (TA group). In the TA group, 10 mg TA was injected in the sub-Tenon space around the AGV plate intraoperatively. Patients were followed for 1 year. The main outcome measure was intraocular pressure (IOP). Other outcome measures included best-corrected visual acuity (BCVA), occurrence of hypertensive phase (HP), peak IOP, number of antiglaucoma medications, and complications. RESULTS A total of 90 patients were included in the final analysis. Mean IOP was lower in the TA group at most follow-up visits; however, the difference was statistically significant only at the first month (p = 0.004). Linear mixed model showed that mean IOP was 1.5 mm Hg lower in the TA group throughout the study period (p = 0.006). Peak postoperative IOP was significantly lower in the TA group (19.3 ± 4.8 mm Hg versus 29 ± 9.2 mm Hg, p = 0.032). Rates of success (defined as 6 < IOP <21 mm Hg) were similar in both groups at 12 months. There was no difference in the occurrence of the HP between the 2 groups (p = 0.123). Loss of BCVA >2 lines was more common in the non-TA group (p = 0.032). CONCLUSIONS Adjunctive intraoperative TA injection during AGV implantation can blunt peak IOP levels and reduce mean IOP up to 1 year. Visual outcomes also seem to be superior to standard surgery.
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A role for antimetabolites in glaucoma tube surgery: current evidence and future directions. Curr Opin Ophthalmol 2016; 27:164-9. [PMID: 26720778 DOI: 10.1097/icu.0000000000000244] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Glaucoma is the leading cause of irreversible blindness worldwide. The main treatment modality for glaucoma is the reduction and control of the intraocular pressure (IOP). Glaucoma filtration surgery, including trabeculectomy and/or implantation of a glaucoma drainage device (GDD), is warranted if IOP remains medically uncontrolled. However, postoperative scarring remains a critical determinant of long-term bleb survival and IOP control after drainage surgery. Antimetabolites, such as mitomycin C and 5-fluorouracil, have been used for many years to increase survival time of filtration surgeries by preventing bleb fibrosis and scarring. The aim of this study is to provide an overview of: the current usage of these antimetabolites in GDD, the recent advancements of these antimetabolites in combination with other technologies, and the role of future antimetabolites. RECENT FINDINGS Mitomycin C and 5-fluorouracil have been used in GDD and trabeculectomy to prevent the exaggerated cellular reaction that leads to fibrosis. The adjunctive administration of these drugs intraoperatively and postoperatively has resulted in a lower rate of the hypertensive phase, and possibly a better long-term success rate in Ahmed valve surgeries. However, the application of these antimetabolites and their multiple-dosing applications are associated with nonspecific cytotoxicity and potentially severe complications such as bleb leak and conjunctival erosion over the tube. Recent studies are thus focusing on different medications, targeting new molecular pathways, and designing new delivery vehicles to minimize current antimetabolites side-effects and increase their efficacy. Promising results of these studies have led to development of new collaborative medications and advanced drug delivery systems for better modulation of GDD surgeries' predictable outcomes. SUMMARY The development of small molecule therapeutics, combination therapies, and innovative drug vehicles to prevent postsurgical fibrosis and achieve better surgical outcome in glaucoma filtration surgeries is promising.
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Qi S, Craig D. Recent developments in micro- and nanofabrication techniques for the preparation of amorphous pharmaceutical dosage forms. Adv Drug Deliv Rev 2016; 100:67-84. [PMID: 26776230 DOI: 10.1016/j.addr.2016.01.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 01/03/2016] [Indexed: 12/27/2022]
Abstract
Nano- and microfabrication techniques have been widely explored in the textile, polymer and biomedical arenas, although more recently these systems have attracted considerable interest as drug delivery vehicles with concomitant considerations of physical characterization, scalability, stability and drug release. In this review, the current thinking with regards to the manufacture of solid amorphous pharmaceutical materials using electrohydrodynamic and gyration-based approaches, melt-spinning approaches, thermal moulding, inkjet printing and 3D printing will be examined in the context of their potential and actual viability as dosage forms. A series of practical examples will be discussed as to how these approaches have been used as means of producing drug delivery systems for a range of delivery systems and treatments.
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Affiliation(s)
- Sheng Qi
- School of Pharmacy, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
| | - Duncan Craig
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
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26
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Dai Z, Yu X, Hong J, Liu X, Sun J, Sun X. Development of a novel CsA-PLGA drug delivery system based on a glaucoma drainage device for the prevention of postoperative fibrosis. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 66:206-214. [PMID: 27207056 DOI: 10.1016/j.msec.2016.04.077] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 04/11/2016] [Accepted: 04/21/2016] [Indexed: 10/21/2022]
Abstract
The formation of a scar after glaucoma surgery often leads to unsuccessful control of intraocular pressure, and should be prevented by using a variety of methods. We designed and developed a novel drug delivery system (DDS) comprising cyclosporine A (CsA) and poly(lactic-co-glycolic acid) (PLGA) based on a glaucoma drainage device (GDD) that can continuously release CsA to prevent postoperative fibrosis following glaucoma surgery. The CsA@PLGA@GDD DDS was observed by field emission scanning electron microscopy and revealed an asymmetric pore structure. Thermogravimetric analysis was performed to measure the weight loss and evaluate the thermal stability of the CsA@PLGA@GDD DDS. The in vitro drug release profile of the DDS was studied using high performance liquid chromatography, which confirmed that the DDS released CsA at a stable rate and maintained adequate CsA concentrations for a relatively long time. The biocompatibility of the DDS and the inhibitory effects on the postoperative fibrosis were investigated in vitro using rabbit Tenon's fibroblasts. The in vivo safety and efficacy of the DDS were examined by implanting the DDS into Tenon's capsules in New Zealand rabbits. Bleb morphology, intraocular pressure, anterior chamber reactions, and anterior chamber angiography were studied at a series of set times. The DDS kept the filtration pathway unblocked for a longer time compared with the control GDD. The results indicate that the CsA@PLGA@GDD DDS represents a safe and effective strategy for preventing scar formation after glaucoma surgery.
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Affiliation(s)
- Zhaoxing Dai
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China
| | - Xiaobo Yu
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China
| | - Jiaxu Hong
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China
| | - Xi Liu
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China
| | - Jianguo Sun
- Research Center, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China; State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200031, China.
| | - Xinghuai Sun
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai 200031, China.
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Arora JS, Cremaldi JC, Holleran MK, Ponnusamy T, He J, Pesika NS, John VT. Hydrogel Inverse Replicas of Breath Figures Exhibit Superoleophobicity Due to Patterned Surface Roughness. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:1009-1017. [PMID: 26752016 DOI: 10.1021/acs.langmuir.5b03870] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The wetting behavior of a surface depends on both its surface chemistry and the characteristics of surface morphology and topography. Adding structure to a flat hydrophobic or oleophobic surface increases the effective contact angle and thus the hydrophobicity or oleophobicity of the surface, as exemplified by the lotus leaf analogy. We describe a simple strategy to introduce micropatterned roughness on surfaces of soft materials, utilizing the template of hexagonally packed pores of breath figures as molds. The generated inverse replicas represent micron scale patterned beadlike protrusions on hydrogel surfaces. This added roughness imparts superoleophobic properties (contact angle of the order of 150° and greater) to an inherently oleophobic flat hydrogel surface, when submerged. The introduced pattern on the hydrogel surface changes morphology as it swells in water to resemble morphologies remarkably analogous to the compound eye. Analysis of the wetting behavior using the Cassie-Baxter approximation leads to estimation of the contact angle in the superoleophobic regime and in agreement with the experimental value.
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Affiliation(s)
- Jaspreet Singh Arora
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Joseph C Cremaldi
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Mary Kathleen Holleran
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Thiruselvam Ponnusamy
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Jibao He
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Noshir S Pesika
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
- Vector Borne Infectious Diseases Research Center, Tulane University , New Orleans, Louisiana 70112, United States
| | - Vijay T John
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
- Vector Borne Infectious Diseases Research Center, Tulane University , New Orleans, Louisiana 70112, United States
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Abstract
Glaucoma is the second leading cause of blindness worldwide, and the antiglaucoma treatments currently available suffer from various complications. Nanotechnology-based treatments show a great deal of promise in overcoming these complications and form the basis for next-generation glaucoma treatment strategies, with the help of applications such as controlled release, targeted delivery, increased bioavailability, diffusion limitations, and biocompatibility. Significant progress has been made in nanomedicine in the efficiency of antiglaucoma medications, nanofabrication systems such as microelectromechanical systems that remove the limitations of nanodevices, and tissue regeneration vesicles for developing glaucoma treatments not based on intraocular pressure. With the use of these advanced technologies, the prevention of glaucoma-induced blindness will be possible in the near future. Herein, we reviewed the recent advances in nanotechnology-based treatment strategies for glaucoma.
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Affiliation(s)
- Sibel Cetinel
- From the Chemical and Materials Engineering and Ingenuity Lab, University of Alberta, Edmonton, Alberta, Canada
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Arora JS, Ponnusamy T, Zheng R, Venkataraman P, Raghavan SR, Blake D, John VT. Spatially directed vesicle capture in the ordered pores of breath-figure polymer films. SOFT MATTER 2015; 11:5188-5191. [PMID: 26021456 DOI: 10.1039/c5sm01068c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This work describes a new method to selectively capture liposomes and other vesicle entities in the patterned pores of breath-figure polymer films. The process involves the deposition of a hydrophobe containing biopolymer in the pores of the breath figure, and the tethering of vesicles to the biopolymer through hydrophobic interactions. The process is versatile, can be scaled up and extended to the deposition of other functional materials in the pores of breath figures.
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Affiliation(s)
- J S Arora
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA 70118, USA.
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Toh ZH, Lee CSY, Chew ACY, Perera S. Time Heals All Wounds: Obstacles in Glaucoma Surgery from an Asian Perspective. PROCEEDINGS OF SINGAPORE HEALTHCARE 2015. [DOI: 10.1177/201010581502400206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide and is a particular burden on the Asian population. Glaucoma surgeries such as trabeculectomy and glaucoma drainage implants are routinely performed to lower intraocular pressure (IOP) to prevent disease progression. However, scarring of the filtering bleb limits their long-term success and Asian eyes are more at risk. Although this is so, many existing studies have been done on Caucasian patients, but few have focused solely on Asian patients. Intraoperative anti-metabolites such as Mitomycin-C (MMC) and 5-Fluorouracil (5-FU) are the current mainstay of adjunctive treatments to reduce scarring, and in this review, we evaluate the evolution, benefits and side effects of these agents. Recently, newer methods of wound modulation including anti-vascular endothelial growth factor (VEGF) agents and collagen implants are also being investigated as part of a multi-pronged approach to tackle this problem. Some opportunities exist to limit scarring post-operatively, but it is an ongoing battle.
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Affiliation(s)
- Zhi Hong Toh
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Schoenberg ED, Blake DA, Swann FB, Parlin AW, Zurakowski D, Margo CE, Ponnusamy T, John VT, Ayyala RS. Effect of Two Novel Sustained-Release Drug Delivery Systems on Bleb Fibrosis: An In Vivo Glaucoma Drainage Device Study in a Rabbit Model. Transl Vis Sci Technol 2015; 4:4. [PMID: 26046006 DOI: 10.1167/tvst.4.3.4] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Accepted: 03/05/2015] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate two drug delivery systems, a nonbiodegradable poly(2-hydroxyethyl methacrylate) (P[HEMA]) system with mitomycin C (MMC) and a biodegradable poly(lactic-co-glycolic acid) (PLGA) system with 5-fluorouracil (5-FU) with and without MMC for their ability to reduce fibrosis when attached to an Ahmed glaucoma valve (AGV) and implanted in a rabbit model. METHODS New Zealand albino rabbits (48) were divided into six equal groups, and AGVs, modified as described below, were implanted in the right eye of each rabbit. The groups included (1) PLGA alone; (2) P(HEMA) plus MMC (6.5 μg); (3) PLGA plus 5-FU (0.45 mg); (4) PLGA plus 5-FU (1.35 mg); (5) PLGA plus 5-FU and MMC (0.45 mg and 0.65 μg, respectively); (6) PLGA plus 5-FU and MMC (1.35 mg and 0.65 μg, respectively). The rabbits were followed for 3 months prior to euthanasia. RESULTS The bleb wall thickness was significantly less in groups 2, 5, and 6 compared to the rest. At 3 months, the PLGA polymer had completely disappeared, while the P(HEMA) polymer remained intact. There were no statistical differences in the degree of clinically graded conjunctival injection, histologic inflammation, or histologic fibrosis among the six groups. CONCLUSIONS We successfully created a sustained-release drug delivery system that decreased the postoperative fibrosis using both a nonbiodegradable P(HEMA) polymer and a biodegradable (PLGA) polymer. Both systems appear to work equally well with no side effects. TRANSLATIONAL RELEVANCE These results are supportive of the antifibrotic effect of the slow-release drug delivery system following glaucoma drainage device implantation, thus paving the way for human pilot studies.
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Affiliation(s)
- Evan D Schoenberg
- Department of Ophthalmology Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Diane A Blake
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - F Beau Swann
- Department of Ophthalmology Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Andrew W Parlin
- Department of Ophthalmology Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - David Zurakowski
- Departments of Anesthesia and Surgery, Harvard Medical School, Boston, Massachusetts, USA
| | - Curtis E Margo
- Department of Ophthalmology, University of South Florida, Tampa, Florida, USA
| | - Thiruselvam Ponnusamy
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana, USA
| | - Vijay T John
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana, USA
| | - Ramesh S Ayyala
- Department of Ophthalmology Tulane University School of Medicine, New Orleans, Louisiana, USA
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Turalba AV, Pasquale LR. Hypertensive phase and early complications after Ahmed glaucoma valve implantation with intraoperative subtenon triamcinolone acetonide. Clin Ophthalmol 2014; 8:1311-6. [PMID: 25050061 PMCID: PMC4103917 DOI: 10.2147/opth.s64257] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objective To evaluate intraoperative subtenon triamcinolone acetonide (TA) as an adjunct to Ahmed glaucoma valve (AGV) implantation. Design Retrospective comparative case series. Participants Forty-two consecutive cases of uncontrolled glaucoma undergoing AGV implantation: 19 eyes receiving intraoperative subtenon TA and 23 eyes that did not receive TA. Methods A retrospective chart review was performed on consecutive pseudophakic adult patients with uncontrolled glaucoma undergoing AGV with and without intraoperative subtenon TA injection by a single surgeon. Clinical data were collected from 42 eyes and analyzed for the first 6 months after surgery. Main outcome measures Primary outcomes included intraocular pressure (IOP) and number of glaucoma medications prior to and after AGV implantation. The hypertensive phase (HP) was defined as an IOP measurement of greater than 21 mmHg (with or without medications) during the 6-month postoperative period that was not a result of tube obstruction, retraction, or malfunction. Postoperative complications and visual acuity were analyzed as secondary outcome measures. Results Five out of 19 (26%) TA cases and 12 out of 23 (52%) non-TA cases developed the HP (P=0.027). Mean IOP (14.2±4.6 in TA cases versus [vs] 14.7±5.0 mmHg in non-TA cases; P=0.78), and number of glaucoma medications needed (1.8±1.3 in TA cases vs 1.6±1.1 in the comparison group; P=0.65) were similar between both groups at 6 months. Although rates of serious complications did not differ between the groups (13% in the TA group vs 16% in the non-TA group), early tube erosion (n=1) and bacterial endophthalmitis (n=1) were noted with TA but not in the non-TA group. Conclusions Subtenon TA injection during AGV implantation may decrease the occurrence of the HP but does not alter the ultimate IOP outcome and may pose increased risk of serious complications within the first 6 months of surgery.
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Affiliation(s)
- Angela V Turalba
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA ; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Louis R Pasquale
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA ; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
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