Publications
350 results found
Bahrani Fard MR, Chan J, Sanchez Rodriguez G, et al., 2023, Improved magnetic delivery of cells to the trabecular meshwork in mice., Exp Eye Res, Vol: 234
Glaucoma is the leading cause of irreversible blindness worldwide and its most prevalent subtype is primary open angle glaucoma (POAG). One pathological change in POAG is loss of cells in the trabecular meshwork (TM), which is thought to contribute to ocular hypertension and has thus motivated development of cell-based therapies to refunctionalize the TM. TM cell therapy has shown promise in intraocular pressure (IOP) control, but existing cell delivery techniques suffer from poor delivery efficiency. We employed a novel magnetic delivery technique to reduce the unwanted side effects of off-target cell delivery. Mesenchymal stem cells (MSCs) were labeled with superparamagnetic iron oxide nanoparticles (SPIONs) and after intracameral injection were magnetically steered towards the TM using a focused magnetic apparatus ("point magnet"). This technique delivered the cells significantly closer to the TM at higher quantities and with more circumferential uniformity compared to either unlabeled cells or those delivered using a "ring magnet" technique. We conclude that our point magnet cell delivery technique can improve the efficiency of TM cell therapy and in doing so, potentially increase the therapeutic benefits and lower the risk of complications such as tumorigenicity and immunogenicity.
Ross Ethier C, Nguyen TV, 2023, Annual Special Issue: Journal of Biomechanical Engineering-2022 in Review., J Biomech Eng, Vol: 145
Safa BN, Bahrani Fard MR, Ethier CR, 2022, In vivo biomechanical assessment of iridial deformations and muscle contractions in human eyes (vol 19, 20220108, 2022), JOURNAL OF THE ROYAL SOCIETY INTERFACE, Vol: 19, ISSN: 1742-5689
Coulon SJ, Schuman JS, Du Y, et al., 2022, A novel glaucoma approach: Stem cell regeneration of the trabecular meshwork, PROGRESS IN RETINAL AND EYE RESEARCH, Vol: 90, ISSN: 1350-9462
- Author Web Link
- Cite
- Citations: 2
Safa BN, Bahrani Fard MR, Ethier CR, 2022, In vivo biomechanical assessment of iridial deformations and muscle contractions in human eyes, JOURNAL OF THE ROYAL SOCIETY INTERFACE, Vol: 19, ISSN: 1742-5689
- Author Web Link
- Cite
- Citations: 1
Ethier CR, Nguyen TV, 2022, ANNUAL SPECIAL ISSUE: Journal of Biomechanical Engineering-Year(s) in Review, JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, Vol: 144, ISSN: 0148-0731
Gerberich BG, Hannon BG, Brown DM, et al., 2022, Evaluation of Spatially Targeted Scleral Stiffening on Neuroprotection in a Rat Model of Glaucoma., Transl Vis Sci Technol, Vol: 11
PURPOSE: Scleral stiffening may protect against glaucomatous retinal ganglion cell (RGC) loss or dysfunction associated with ocular hypertension. Here, we assess the potential neuroprotective effects of two treatments designed to stiffen either the entire posterior sclera or only the sclera adjacent to the peripapillary sclera in an experimental model of glaucoma. METHODS: Rat sclerae were stiffened in vivo using either genipin (crosslinking the entire posterior sclera) or a regionally selective photosensitizer, methylene blue (stiffening only the juxtaperipapillary region surrounding the optic nerve). Ocular hypertension was induced using magnetic microbeads delivered to the anterior chamber. Morphological and functional outcomes, including optic nerve axon count and appearance, retinal thickness measured by optical coherence tomography, optomotor response, and electroretinography traces, were assessed. RESULTS: Both local (juxtaperipapillary) and global (whole posterior) scleral stiffening treatments were successful at increasing scleral stiffness, but neither provided demonstrable neuroprotection in hypertensive eyes as assessed by RGC axon counts and appearance, optomotor response, or electroretinography. There was a weak indication that scleral crosslinking protected against retinal thinning as assessed by optical coherence tomography. CONCLUSIONS: Scleral stiffening was not demonstrated to be neuroprotective in ocular hypertensive rats. We hypothesize that the absence of benefit may in part be due to RGC loss associated with the scleral stiffening agents themselves (mild in the case of genipin, and moderate in the case of methylene blue), negating any potential benefit of scleral stiffening. TRANSLATIONAL RELEVANCE: The development of scleral stiffening as a neuroprotective treatment will require the identification of better tolerated stiffening protocols and further preclinical testing.
Feola AJ, Girkin CA, Ethier CR, et al., 2022, A Potential Role of Acute Choroidal Expansion in Nonarteritic Anterior Ischemic Optic Neuropathy, INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE, Vol: 63, ISSN: 0146-0404
Safa BN, Read AT, Ethier CR, 2022, Assessment of the viscoelastic mechanical properties of the porcine optic nerve head using micromechanical testing and finite element modeling (vol 134, pg 379, 2021), ACTA BIOMATERIALIA, Vol: 141, Pages: 481-483, ISSN: 1742-7061
Safa BN, Wong CA, Ha J, et al., 2022, Glaucoma and biomechanics, CURRENT OPINION IN OPHTHALMOLOGY, Vol: 33, Pages: 80-90, ISSN: 1040-8738
- Author Web Link
- Cite
- Citations: 4
McDowell CM, Kizhatil K, Elliott MH, et al., 2022, Consensus recommendation for mouse models of ocular hypertension to study aqueous humor outflow and its mechanisms, Investigative Ophthalmology and Visual Science, Vol: 63, ISSN: 0146-0404
Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings.
Chan D, Won GJ, Read AT, et al., 2022, Application of an organotypic ocular perfusion model to assess intravitreal drug distribution in human and animal eyes, JOURNAL OF THE ROYAL SOCIETY INTERFACE, Vol: 19, ISSN: 1742-5689
Jasien J, Read AT, Van Batenburg-Sherwood J, et al., 2022, Correspondence: Brian C. Samuels, ; bsamuels@uab.edu. PURPOSE. both model anatomy, anatomy purpose, INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE, Vol: 63, ISSN: 0146-0404
Safa BN, Read AT, Ethier CR, 2021, Assessment of the viscoelastic mechanical properties of the porcine optic nerve head using micromechanical testing and finite element modeling, ACTA BIOMATERIALIA, Vol: 134, Pages: 379-387, ISSN: 1742-7061
- Author Web Link
- Cite
- Citations: 6
Hannon BG, Feola AJ, Gerberich BG, et al., 2021, Using retinal function to define ischemic exclusion criteria for animal models of glaucoma (vol 202, 108354, 2021), EXPERIMENTAL EYE RESEARCH, Vol: 210, ISSN: 0014-4835
Allen RS, Motz CT, Singh A, et al., 2021, Dependence of visual and cognitive outcomes on animal holder configuration in a rodent model of blast overpressure exposure, VISION RESEARCH, Vol: 188, Pages: 162-173, ISSN: 0042-6989
Ethier CR, 2021, Editorial: A Message From C. Ross Ethier, the New JBME Co-Editor, JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, Vol: 143, ISSN: 0148-0731
Sater SH, Sass AM, Seiner A, et al., 2021, MRI-based quantification of ophthalmic changes in healthy volunteers during acute 15 degrees head-down tilt as an analogue to microgravity, JOURNAL OF THE ROYAL SOCIETY INTERFACE, Vol: 18, ISSN: 1742-5689
- Author Web Link
- Cite
- Citations: 1
Safa BN, Read AT, Ethier CR, 2021, Assessment of the Viscoelastic Mechanical Properties of the Porcine Optic Nerve Head using Micromechanical Testing and Finite Element Modeling
<jats:title>Abstract</jats:title><jats:p>Optic nerve head (ONH) biomechanics is centrally involved in the pathogenesis of glaucoma, a blinding ocular condition often characterized by elevation and fluctuation of the intraocular pressure and resulting loads on the ONH. Further, tissue viscoelasticity is expected to strongly influence the mechanical response of the ONH to mechanical loading, yet the viscoelastic mechanical properties of the ONH remain unknown. To determine these properties, we conducted micromechanical testing on porcine ONH tissue samples, coupled with finite element modeling based on a mixture model consisting of a biphasic material with a viscoelastic solid matrix. Our results provide a detailed description of the viscoelastic properties of the porcine ONH at each of its four anatomical quadrants (i.e., nasal, superior, temporal, and inferior). We showed that the ONH’s viscoelastic mechanical response can be explained by a dual mechanism of fluid flow and solid matrix viscoelasticity, as is common in other soft tissues. We obtained porcine ONH properties as follows: matrix Young’s modulus <jats:italic>E</jats:italic>=1.895 [1.056,2 .391] kPa (median [min., max.]), Poisson’s ratio <jats:italic>ν</jats:italic>=0.142 [0.060,0 .312], kinetic time-constant <jats:italic>τ</jats:italic>=214 [89,921] sec, and hydraulic permeability <jats:italic>k</jats:italic>=3.854 × 10<jats:sup>−1</jats:sup> [3.457 × 10<jats:sup>−2</jats:sup>,9.994 × 10<jats:sup>−1</jats:sup>] mm<jats:sup>4</jats:sup>/(N sec). These values can be used to design and fabricate physiologically appropriate <jats:italic>ex vivo</jats:italic> test environments (e.g., 3D cell culture) to further understand glaucoma pathophysiology.</jats:p>
Yun H, Wang Y, Zhou Y, et al., 2021, Human stem cells home to and repair laser-damaged trabecular meshwork in a mouse model (vol 6, 216, 2018), COMMUNICATIONS BIOLOGY, Vol: 4
Yun H, Wang Y, Zhou Y, et al., 2021, Human stem cells home to and repair laser-damaged trabecular meshwork in a mouse model (vol 6, 216, 2018), COMMUNICATIONS BIOLOGY, Vol: 4
Schwaner SA, Perry RN, Kight AM, et al., 2021, Individual-Specific Modeling of Rat Optic Nerve Head Biomechanics in Glaucoma, JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, Vol: 143, ISSN: 0148-0731
- Author Web Link
- Cite
- Citations: 3
Li G, Lee C, Read AT, et al., 2021, Anti-fibrotic activity of a rho-kinase inhibitor restores outflow function and intraocular pressure homeostasis, ELIFE, Vol: 10, ISSN: 2050-084X
- Author Web Link
- Cite
- Citations: 14
Gerberich BG, Hannon BG, Hejri A, et al., 2021, Transpupillary collagen photocrosslinking for targeted modulation of ocular biomechanics, BIOMATERIALS, Vol: 271, ISSN: 0142-9612
- Author Web Link
- Cite
- Citations: 4
Snider EJ, Hardie BA, Li Y, et al., 2021, A Porcine Organ-Culture Glaucoma Model Mimicking Trabecular Meshwork Damage Using Oxidative Stress, INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE, Vol: 62, ISSN: 0146-0404
- Author Web Link
- Cite
- Citations: 5
Safa BN, Santare MH, Ethier CR, et al., 2021, Identifiability of tissue material parameters from uniaxial tests using multi-start optimization, ACTA BIOMATERIALIA, Vol: 123, Pages: 197-207, ISSN: 1742-7061
- Author Web Link
- Cite
- Citations: 5
Zhu W, Hou F, Fang J, et al., 2021, The role of Piezo1 in conventional aqueous humor outflow dynamics, iScience, Vol: 24, Pages: 1-32, ISSN: 2589-0042
Controlling intraocular pressure (IOP) remains the mainstay of glaucoma therapy. The trabecular meshwork (TM), the key tissue responsible for aqueous humor (AH) outflow and IOP maintenance, is very sensitive to mechanical forces. However, it is not understood whether Piezo channels, very sensitive mechanosensors, functionally influence AH outflow. Here, we characterize the role of Piezo1 in conventional AH outflow. Immunostaining and western blot analysis showed that Piezo1 is widely expressed by TM. Patch-clamp recordings in TM cells confirmed the activation of Piezo1-derived mechanosensitive currents. Importantly, the antagonist GsMTx4 for mechanosensitive channels significantly decreased steady-state facility, yet activation of Piezo1 by the specific agonist Yoda1 did not lead to a facility change. Furthermore, GsMTx4, but not Yoda1, caused a significant increase in ocular compliance, a measure of the eye's transient response to IOP perturbation. Our findings demonstrate a potential role for Piezo1 in conventional outflow, likely under pathological and rapid transient conditions.
Zahid AM, Martin B, Collins S, et al., 2021, Quantification of arterial, venous, and cerebrospinal fluid flow dynamics by magnetic resonance imaging under simulated micro-gravity conditions: a prospective cohort study, FLUIDS AND BARRIERS OF THE CNS, Vol: 18, ISSN: 2045-8118
- Author Web Link
- Cite
- Citations: 3
Boazak EM, King R, Wang J, et al., 2021, Smarce1 and Tensin 4 are putative modulators of corneoscleral stiffness, Frontiers in Bioengineering and Biotechnology, Vol: 9, Pages: 1-13, ISSN: 2296-4185
The biomechanical properties of the cornea and sclera are important in the onset and progression of multiple ocular pathologies and vary substantially between individuals, yet the source of this variation remains unknown. Here we identify genes putatively regulating corneoscleral biomechanical tissue properties by conducting high-fidelity ocular compliance measurements across the BXD recombinant inbred mouse set and performing quantitative trait analysis. We find seven cis-eQTLs and non-synonymous SNPs associating with ocular compliance, and show by RT-qPCR and immunolabeling that only two of the candidate genes, Smarce1 and Tns4, showed significant expression in corneal and scleral tissues. Both have mechanistic potential to influence the development and/or regulation of tissue material properties. This work motivates further study of Smarce1 and Tns4 for their role(s) in ocular pathology involving the corneoscleral envelope as well as the development of novel mouse models of ocular pathophysiology, such as myopia and glaucoma.
Sater SH, Sass AM, Rohr JJ, et al., 2021, Automated MRI-based quantification of posterior ocular globe flattening and recovery after long-duration spaceflight, EYE, Vol: 35, Pages: 1869-1878, ISSN: 0950-222X
- Author Web Link
- Cite
- Citations: 6
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.