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1.
Pharm Res ; 41(6): 1247-1256, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38839719

ABSTRACT

PURPOSE: Wet age-related macular degeneration (AMD) is a blinding retinal disease. Monthly intravitreal anti-VEGF antibody injections of bevacizumab (off-label) and ranibizumab (FDA approved) are the standard of care. Antibody aggregation may interfere with ocular absorption/distribution. This study assessed topical delivery of dilute antibodies to the posterior segment of rabbit eyes using a novel anti-aggregation formula (AAF). METHODS: Bevacizumab, or biosimilar ranibizumab was diluted to 5 mg/ml in AAF. All rabbits were dosed twice daily. Substudy 1 rabbits (bevacizumab, 100 µl eye drops): Group 1 (bevacizumab/AAF, n = 6); Group 2 (bevacizumab/PBS, n = 7) and Vehicle control (AAF, n = 1). Substudy 2 rabbits (ranibizumab biosimilar/AAF, 50 µl eye drops): (ranibizumab biosimilar/AAF, n = 8). At 14.5 days, serum was drawn from rabbits. Aqueous, vitreous and retina samples were recovered from eyes and placed into AAF aliquots. Tissue analyzed using AAF as diluent. RESULTS: Bevacizumab in AAF permeated/accumulated in rabbit aqueous, vitreous and retina 10 times more, than when diluted in PBS. AAF/0.1% hyaluronic acid eye drops, dosed twice daily, provided mean tissue concentrations (ng/g) in retina (29.50), aqueous (12.34), vitreous (3.46), and serum (0.28 ng/ml). Additionally, the highest concentration (ng/g) of ranibizumab biosimilar was present in the retina (18.0), followed by aqueous (7.82) and vitreous (1.47). Serum concentration was negligible (< 0.04 ng/ml). No irritation was observed throughout the studies. CONCLUSIONS: Bevacizumab and ranibizumab, in an AAF diluent eye drop, can be delivered to the retina, by the twice daily dosing of a low concentration mAb formulation. This may prove to be an adjunct to intravitreal injections.


Subject(s)
Bevacizumab , Ophthalmic Solutions , Ranibizumab , Retina , Animals , Ranibizumab/administration & dosage , Ranibizumab/pharmacokinetics , Rabbits , Bevacizumab/administration & dosage , Bevacizumab/pharmacokinetics , Ophthalmic Solutions/administration & dosage , Retina/metabolism , Retina/drug effects , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/pharmacokinetics , Vitreous Body/metabolism , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Intravitreal Injections , Biosimilar Pharmaceuticals/administration & dosage , Biosimilar Pharmaceuticals/pharmacokinetics , Wet Macular Degeneration/drug therapy
2.
BMJ Open Ophthalmol ; 8(1)2023 12 28.
Article in English | MEDLINE | ID: mdl-38154911

ABSTRACT

PURPOSE: To test the use of Ring-IT, a novel 3D tactile bottle neck adaptor in topical eye drop adherence in visually impaired patients. METHODS: Bottle neck ring adaptors with either one, two or three protrusions with cube or sphere endings were designed. In phase 1, low vision was simulated in healthy subjects (n=20) with a 20/200 vision simulator; while in phase 2, visually impaired patients (n=26; 20/70 or worse) were recruited. Subjects were randomised to six combinations of varying protrusions and shapes on medication bottles and asked to identify these traits at different presentations. Responses and time to identify were recorded. RESULTS: Phase 1: 98.3% of subjects correctly identified the number of protrusions. Mean time to identify was 4.5±6.1 s. Identification success for cube and sphere end pieces were 91.7% and 73.3%, with average time for identification of 9.9±7.6 and 10.9±9.0 s. In phase 2, 92.3% of subjects correctly identified the number of protrusions. Mean time to identify was 6.0±3.0 s. Identification success for cube and sphere end pieces were 78.2% and 74.4%; with average time for identification of 7.5±4.8 and 8.5±5.6 s, respectively. CONCLUSIONS: Ring-IT was identified with accuracy and speed by both low vision simulated subjects, and by patients with true limited visual capabilities. These tactile bottle neck ring adaptors can be used as an assistive low vision aid device and may increase eye drop regimen adherence in visually impaired patients.


Subject(s)
Self-Help Devices , Vision, Low , Humans , Ophthalmic Solutions , Refraction, Ocular
3.
Clin Ophthalmol ; 17: 375-383, 2023.
Article in English | MEDLINE | ID: mdl-36721668

ABSTRACT

Purpose: To compare the PRN anti-VEGF injection patterns of four retina specialists with respect to the visual and anatomic outcomes in the management of wet age-related macular degeneration (AMD). Methods: Medical records of patients who received bevacizumab, ranibizumab, and aflibercept anti-VEGF injections (years 2010-2020) by four retina specialists were reviewed for frequency, injection intervals, best corrected visual acuity (BCVA), and central macular thickness, center involved (CMT) for statistical analysis. Outcomes measured were change in logMAR BCVA and CMT from the first to last injection visit. Results: Out of 137 AMD patients, 172 eyes were injected by four retina specialists in PRN fashion. Although all four specialists started the injection at similar baseline BCVA and CMT (p > 0.1), significant differences in mean injection number (9.0, p = 0.0001), injection intervals (5.06 weeks, p = 0.001), and total length of treatments (53.3 weeks, p = 0.0001) were observed. The mean change in logMAR BCVA between the first and last injection was -0.05, -0.22, 0.07, and 0.06 for the four specialists, respectively (p = 0.031), and the mean change in CMT was -53.3, -41.4, -72.7, and -21.9 µm (p = 0.41), respectively. Conclusion: Despite similar baseline criteria for injections by the retina specialists, different anti-VEGF injection regimens were practiced resulting in variations in BCVA and CMT outcomes. This suggests a need in establishing a universally adoptable injection regimen with possible integration of the confounding factors to reduce burden on both patients and retina specialists.

4.
Clin Ophthalmol ; 16: 2561-2568, 2022.
Article in English | MEDLINE | ID: mdl-35978609

ABSTRACT

Purpose: Long-term video game play and its effects on the skills used in surgical simulators have been previously studied, but little information is available about short-term video game warm-ups and subsequent ophthalmic surgical simulation performance. In this study, we hypothesize that a video game warm-up will improve performance on the Eyesi Ophthalmic Surgical Simulator. Methods: Twenty medical students with no prior surgical simulation experience were recruited for the study. Information regarding prior video game experience was gathered, and half of the participants were then randomly assigned to play a video game session prior to Eyesi performance. All subjects completed three sets of Eyesi modules, and the scores and time to completion were recorded. Bivariate analysis including Fisher's Exact test and Wilcoxon rank-sum test were used for statistical analysis. Results: The warm-up group scored higher in Navigation, Bimanual, and Forceps modules (33.6, 39.7, 7.2, respectively) compared to non-warm-up group (27.3, 27.3, 3.6, respectively). In addition, average times (sec) were lower (310.5, 117.4, 229.2, respectively) compared to non-warm-up group (321.9, 163.3, 235.8, respectively). It was also observed that significantly more participants in the warm-up group had reported a history of spending >15 hours per week playing video games compared to the non-warm-up group (80% vs 20%, p=0.0402). Conclusion: In our pilot study, there appears to be a positive trend between video game warm-up and Eyesi simulation performance; however, no statistically significant difference was observed due to lower power. This trend can be explained by a greater collective video game experience within the warm-up group, mechanical factors (increased flexibility and grip strength after playing video games) and feeling more relaxed after the video game warm-up. Larger follow-up studies are needed to further investigate the relationship between short-term video game use on ophthalmic surgical simulation performance.

5.
Clin Pract ; 12(4): 619-627, 2022 Aug 11.
Article in English | MEDLINE | ID: mdl-36005068

ABSTRACT

(1) Purpose: In 2020, wearing of face masks was mandated in the United States in an effort to lessen transmission of the novel 2019 coronavirus disease (COVID-19) pandemic; however, long-term mask wearing may present with unintended side-effects in both ophthalmic and otolaryngologic clinical practice. This study aims to examine if mask wearing increased the incidence of primarily chalazion, blepharoconjunctivitis, and rhinitis occurrence during the mask-mandated COVID-19 pandemic period. (2) Methods: Medical records from tertiary academic center clinics were analyzed for incidence of ophthalmic and otolaryngologic diagnoses of interest (blepharoconjunctivitis- and rhinitis-related disorders). Data were collected from a pre-pandemic (March 2019-February 2020) and a mid-pandemic window (March 2020-February 2021) during which widespread mask mandates were implemented in Texas. Comparison was performed using a t-test analysis between incidence of chosen diagnoses during the described time periods. (3) Results: Incidence of ophthalmic disorders (primarily blepharoconjunctivitis and chalazion) in the pre-pandemic versus mid-pandemic windows did show a significant difference (p-value of 0.048). Similarly, comparison of otolaryngologic diagnoses (primarily rhinitis and related conditions) between the two time periods showed a significant difference (p-value of 0.044) as well. (4) Conclusion: Incidence of the chosen ophthalmic and otolaryngologic disorders did increase during periods of mask mandates. While these findings are preliminary, further studies are warranted to understand other factors that may have played a role in eye and nose pathology.

6.
Exp Eye Res ; 223: 109210, 2022 10.
Article in English | MEDLINE | ID: mdl-35987418

ABSTRACT

Pathological features of alkali concentration-associated burn were studied using non-invasive anterior segment optical coherence tomography (AS-OCT) and OCT angiography (OCTA). Alkali burn was induced in C57BL/6J mice (n = 20) by placing filter paper soaked in 0.1, 0.25, 0.5, and 1 M NaOH for 30s on the right eye (left eye control). Longitudinal imaging was performed with AS-OCT/OCTA and fluorescein angiography over 14 days, after which eyes were enucleated at 7 and 14 days for histology and immunofluorescence. Concentration-associated corneal swelling was maximal at 0.5M, increasing linearly in a concentration-dependent fashion at 0.1, 0.25, and 0.5 M NaOH, to levels of 50%, 100%, and 175% of control, respectively. At 0.1M, corneal swelling and surface erosions were prominent, while at 0.25M, deep tissue damage, limbal neovascularization, and stromal haze were evident at 7 days. At 0.5M and 1M, severe exacerbation of the corneal swelling, angle closure, Descemet's membrane detachment, hyphema, and profuse central neovascularization were noted as early as day 3, which further progressed to inflammation, fibrosis, and opacity by day 7. We conclude that alkali concentration-dependent burn intensity biomarkers can be assessed by non-invasive AS-OCT/OCTA, distinguishing between mild, moderate, and severe ocular injury, with potential relevance toward clinical utilization in human eyes.


Subject(s)
Burns, Chemical , Corneal Edema , Animals , Biomarkers , Burns, Chemical/diagnostic imaging , Burns, Chemical/pathology , Disease Models, Animal , Fluorescein Angiography/methods , Humans , Mice , Mice, Inbred C57BL , Sodium Hydroxide/toxicity , Tomography, Optical Coherence/methods
7.
J Ophthalmol ; 2021: 6122246, 2021.
Article in English | MEDLINE | ID: mdl-34881054

ABSTRACT

Low-vision rehabilitation (LVR) has significant benefit in improving the quality of life of visually impaired patients. However, these services are highly underutilized in ophthalmology practices. A quality improvement study was performed to investigate barriers to LVR services for patients at the University of Texas Medical Branch (UTMB) between 2010 and 2020. Low vision was defined as the best corrected visual acuity of 20/70 or worse in the better-seeing eye or a visual field less than 20 degrees. Potential subjects were screened (n = 577) from the electronic medical record using International Classification of Disease (ICD) codes for legal blindness, impaired vision, and low vision. Chart review identified 190 subjects who met criteria for low-vision analysis. Patients who received LVR referrals to attend at least one LVR service visit from the eligible subjects were contacted for participation in phone interviews regarding their LVR experience. Practicing eye care providers (ECPs) at UTMB completed a questionnaire to capture their referral patterns. Of the eligible subjects, 64% were referred to LVR services by ECPs. Reported patient barriers included mental health issues (76%), denial of need for low-vision aid (71%), poor physical health (67%), lack of transportation (57.1%), and lack of referrals (36%). EPCs reported patient's overall health (67%), older age (44%), lack of social support (44%), poor cognitive function (44%), and low likelihood of follow-up (44%) as barriers to referring patients to LVR. This study identified several modifiable barriers that can be addressed to access LVR services for low-vision patients. Changing referral patterns, eliminating variations in referral criteria, and increasing patient awareness and knowledge of LVR resources may tremendously improve the quality of life of low-vision patients.

8.
Cureus ; 13(9): e18192, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34722017

ABSTRACT

Purpose This is a retrospective study of primary open-angle glaucoma patients treated with the immunosuppressor FK506 (tacrolimus) after an organ transplant. We assessed whether FK506 might be a potential neuroprotector adjuvant in glaucoma therapy. Patients and methods Organ transplant patients treated with FK506 for one or more years between 2006 and 2017 at the University of Texas Medical Branch (UTMB) were enrolled. Those selected were patients older than or equal to 50 years of age and had an ophthalmological eye examination with or without diagnostic tests for primary open-angle glaucoma (POAG). Sixty-one eligible subjects were included in the study and matched with the non-FK506 control group for age, gender, race, and follow-up visits. Results A lower incidence of POAG was noted in the FK506-treated patients (15%) when compared to the non-FK506 group (22%), though not significant (p=0.34). Among POAG subjects, the average retinal nerve fiber layer (RNFL) thickness decreased at a rate of 1.4 µm per year (p=0.0001) in the non-FK506 control patients versus 0.4 µm per year (p=0.34) in the FK506 patients. The superior and inferior RNFL quadrants in the control non-FK506 group had a thinning of 2.2 µm and 2.3 µm per year, respectively, (p=0.003 and p=0.0001), while in the FK506 patients, there was no significant loss. In addition, RNFL thinning in nasal and temporal quadrant also showed less reduction in FK506-treated subjects but was not statistically significant (p=0.68 and p=0.93). Conclusion FK506 therapy offers a new promising avenue for neuroprotection in POAG patients and needs to be investigated further for use in conjunction with conventional glaucoma treatments.

9.
Transl Vis Sci Technol ; 10(3): 6, 2021 03 01.
Article in English | MEDLINE | ID: mdl-34003940

ABSTRACT

Purpose: Chemical burns due to alkalis cause extensive damage to the ocular surface leading to blindness. Assessment of ocular burn could be challenging due to severe opacity, inflammation, and angiogenesis. Anterior segment optical coherence tomography (AS-OCT) and OCT angiography (OCTA) may provide fast, non-invasive deep tissue visualization of pathology with high sensitivity in conjunction with slit-lamp analysis. Methods: C57-BL/6J mice were anesthetized with ketamine/dexmedetomidine, and corneal alkali burn was induced (n = 6) by placing filter paper soaked in 1-M sodium hydroxide for 30 seconds on the right eye while the left eye was kept as control. Longitudinal imaging was done with AS-OCT/OCTA and fluorescein angiography at various time intervals for 14 days. Results: AS-OCT showed characteristic pathological changes in alkali-burned eyes with high sensitivity. Although OCT/OCTA showed three-dimensional and cross-sectional views of the anterior chamber and angiogenesis, fluorescein angiography showed nascent vessels with active leakage. Corneal swelling progressively increased by 125.26% on day 12 with a high prevalence of epithelial bullae, stromal cysts, stromal splitting, and Descemet's membrane detachment. Neovascularization was noted as early as day 4 in the burned eyes by both methods. Severe corneal opacity and anterior chamber inflammation were also detected by AS-OCT/OCTA. Conclusions: AS-OCT/OCTA is a promising, noninvasive, high-resolution imaging modality that can provide both qualitative and quantitative information regarding deep tissue pathology at a structural level. Translational Relevance: Noninvasive AS-OCT/OCTA and fluorescein methods show promise in clinical pathology evaluation for ocular injury management and prognostic indications, as the early presence of Descemet's membrane detachment and corneal swelling appears to be correlated with the severity and localization of corneal neovascularization.


Subject(s)
Alkalies , Tomography, Optical Coherence , Animals , Cornea/diagnostic imaging , Cross-Sectional Studies , Fluorescein Angiography , Mice
10.
Life (Basel) ; 12(1)2021 Dec 31.
Article in English | MEDLINE | ID: mdl-35054444

ABSTRACT

Intravitreal anti-VEGF injections are the current gold standard for treating diabetic macular edema (DME). However, injection practice patterns of retina specialists have varied markedly based on physician discretion. This retrospective study analyzes the impact of injection protocol selection on change in best-corrected visual acuity (BCVA) and central macular thickness (CMT) in 170 eyes treated by 4 retina specialists practicing a pro re nata (PRN) strategy between 2010 and 2020. DME patients received an average of 7.25 injections every 6.24 weeks over 56.6 weeks. There were significant differences between retina specialists in mean number of injections (p = 0.0001) and mean length of treatment (p = 0.0007) but not in mean interval between injections. Over the treatment period, average change in BCVA was -0.053 logMAR, and average change in CMT was -51.1 µm, neither of which had significant differences between retina specialists. BCVA and CMT at initial visit were found to be significantly associated with improved BCVA and CMT over the treatment period (p < 0.001). Number of injections administered and interval between injections were not found to be significant factors affecting change in BCVA or CMT. Despite significant differences in injection dosing regimen, retina specialists achieved similar outcomes in change in BCVA and CMT over the treatment period.

11.
J Nutr ; 136(1): 64-9, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16365060

ABSTRACT

Butyrate inhibits colonic cell proliferation in vitro but reportedly has an opposite effect in vivo. Because lactulose feeding decreases cecal cell proliferation, an effect attenuated by prefeeding inulin, we hypothesized that lactulose feeding would decrease colonic luminal synthesis of butyrate, and that prefeeding and cofeeding inulin would prevent this effect. Piglets (n = 31) were catheterized and randomly assigned to 1 of 4 groups: Control formula (C); control formula + lactulose (L); control formula + lactulose + inulin (L + I); and control formula + inulin (I). At 6 and 7 d postsurgery, the rate of cecal synthesis of butyrate, cecal cell proliferation and apoptosis, and cecal and distal colon butyrate concentration were measured. In groups C, L, L + I, and I, the rates of synthesis of butyrate (mean +/- SEM) were 10.6 +/- 3.2, 23.3 +/- 4.5, 12.4 +/- 3.6, and 14.6 +/- 4.0 micromol/min, respectively (Group Effect, P = 0.1; C vs. L, P = 0.03; L vs. L + I, P = 0.06). The cecal butyrate concentrations did not differ among the 4 groups and were 8.7 +/- 3.2, 2.4 +/- 0.8, 3.4 +/- 1.9, and 2.0 +/- 0.7 micromol/g dry wt, respectively. The total cecal cell proliferation index was higher in C than in L (P = 0.008) or I (P = 0.026) and was higher in L + I than in L (P = 0.013) or I (P = 0.046). The increased supply of butyrate to the cecum was associated with decreased cell proliferation, but cecal butyrate concentration did not reflect synthesis.


Subject(s)
Butyric Acid/metabolism , Cell Proliferation/drug effects , Colon/metabolism , Gastrointestinal Agents/adverse effects , Inulin/pharmacology , Lactulose/antagonists & inhibitors , Animals , Apoptosis/drug effects , Butyric Acid/blood , Colon/drug effects , Gastrointestinal Agents/pharmacology , Lactulose/pharmacology , Swine
12.
Comb Chem High Throughput Screen ; 5(4): 289-99, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12052180

ABSTRACT

While the in vitro selection of nucleic acid binding species (aptamers) requires numerous liquid-handling steps, these steps are relatively straightforward and the overall process is therefore amenable to automation. Here we demonstrate that automated selection techniques are capable of generating aptamers against a number of diverse protein targets. Automated selection techniques can be integrated with automated analytical methods, including sequencing, determination of binding constants, and structural analysis. The methods that have so far been developed can be further multiplexed, and it should soon be possible to attempt the selection of aptamers against organismal proteomes or metabolomes.


Subject(s)
Automation , Combinatorial Chemistry Techniques , Oligodeoxyribonucleotides/chemistry , Base Sequence , Ligands , Molecular Sequence Data
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