Publications by authors named "Collin Richards"

Purpose: Clinical trial cohorts frequently differ demographically from the overall population receiving treatment for the condition under study. Our study describes the racial, ethnic, and gender composition of the cohorts of retinal vein occlusion (RVO) macular edema (ME) clinical trials and compares this to the racial, ethnic, and gender composition of patients undergoing treatment for ME secondary to RVO from the (Intelligent Research in Sight) IRIS Registry.

Design: Retrospective observational case series Subjects: Participants in RVO-ME clinical trials that met the following inclusion criteria: conducted in the United States of America, Phase III completed, data reported between January 1, 2000, and January 1, 2020, and demographic information reported with results.

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Inherited retinal diseases (IRDs) are a significant contributor to visual loss in children and young adults, falling second only to diabetic retinopathy. Understanding the pathogenic mechanisms of IRDs remains paramount. Some autosomal genes exhibit random allelic expression (RAE), similar to X-chromosome inactivation.

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Purpose: To evaluate surgeon performance and intraoperative complication rates of cataract surgery after resumption of elective surgeries following the operating room (OR) shutdown from the coronavirus disease 2019 (COVID-19) pandemic. Subjective surgical experience is also evaluated.

Methods: This is a retrospective comparative study which analyzes cataract surgeries performed at an inner city, tertiary academic center.

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Our understanding of the biological functions of the tau protein now includes its role as a scaffolding protein involved in signaling regulation, which also has implications for tau-mediated dysfunction and degeneration in Alzheimer's disease and other tauopathies. Recently, we found that pseudophosphorylation at sites linked to the pathology-associated AT8 phosphoepitope of tau disrupts normal fast axonal transport through a protein phosphatase 1 (PP1)-dependent pathway in squid axoplasm. Activation of the pathway and the resulting transport deficits required tau's N-terminal phosphatase-activating domain (PAD) and PP1 but the connection between tau and PP1 was not well defined.

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Purpose: Poor eye-health knowledge and health literacy are pervasive, contributing to worse outcomes. This study aims to examine short- and long-term eye-health knowledge retention following eye-health education interventions in adults.

Methods: Vision Detroit was an outreach vision screening program that integrated a 5-Point Teaching Intervention (5PTI), at a Southwest Community Center (SW-CC) from 2015-2017.

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Pathologic tau modifications are characteristic of Alzheimer's disease and related dementias, but mechanisms of tau toxicity continue to be debated. Inherited mutations in tau cause early onset frontotemporal lobar dementias (FTLD-tau) and are commonly used to model mechanisms of tau toxicity in tauopathies. Previous work in the isolated squid axoplasm model demonstrated that several pathogenic forms of tau inhibit axonal transport through a mechanism involving activation of protein phosphatase 1 (PP1).

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Purpose: The phosphodiesterase inhibitor sildenafil is a promising treatment for neurodegenerative disease, but it can cause oxidative stress in photoreceptors ex vivo and degrade visual performance in humans. Here, we test the hypotheses that in wildtype mice sildenafil causes i) wide-spread photoreceptor oxidative stress in vivo that is linked with ii) impaired vision.

Methods: In dark or light-adapted C57BL/6 mice ± sildenafil treatment, the presence of oxidative stress was evaluated in retina laminae in vivo by QUEnch-assiSTed (QUEST) magnetic resonance imaging, in the subretinal space in vivo by QUEST optical coherence tomography, and in freshly excised retina by a dichlorofluorescein assay.

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Purpose: Vision loss and blindness are among the top ten disabilities in the United States, yet access and utilization of eye care remains low. Vision Detroit aimed to address eye-care disparities via community-based screenings. By investigating burden of eye disease and barriers to eye-care utilization in an underserved urban community, we may direct efforts to improve access.

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Purpose: To test the hypothesis that imaging biomarkers are useful for evaluating in vivo rod photoreceptor cell responses to a mitochondrial protonophore.

Methods: Intraperitoneal injections of either the mitochondrial uncoupler 2,4 dinitrophenol (DNP) or saline were given to mice with either higher [129S6/eVTac (S6)] or lower [C57BL/6J (B6)] mitochondrial reserve capacities and were studied in dark or light. We measured: (i) the external limiting membrane-retinal pigment epithelium region thickness (ELM-RPE; OCT), which decreases substantially with upregulation of a pH-sensitive water removal co-transporter on the apical portion of the RPE, and (ii) the outer retina R1 (= 1/(spin lattice relaxation time (T1), an MRI parameter proportional to oxygen / free radical content.

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