Peyton A. Rather

Bio: Peyton A. Rather is an academic researcher from University of Arkansas. The author has contributed to research in topics: Courtship & Mate choice. The author has co-authored 1 publications.

Current and Novel Therapeutic Approaches for Treatment of Diabetic Macular Edema

Abstract: Diabetic macular edema (DME) is a major ocular complication of diabetes mellitus (DM), leading to significant visual impairment. DME’s pathogenesis is multifactorial. Focal edema tends to occur when primary metabolic abnormalities lead to a persistent hyperglycemic state, causing the development of microaneurysms, often with extravascular lipoprotein in a circinate pattern around the focal leakage. On the other hand, diffusion edema is due to a generalized breakdown of the inner blood–retinal barrier, leading to profuse early leakage from the entire capillary bed of the posterior pole with the subsequent extravasation of fluid into the extracellular space. The pathogenesis of DME occurs through the interaction of multiple molecular mediators, including the overexpression of several growth factors, including vascular endothelial growth factor (VEGF), insulin-like growth factor-1, angiopoietin-1, and -2, stromal-derived factor-1, fibroblast growth factor-2, and tumor necrosis factor. Synergistically, these growth factors mediate angiogenesis, protease production, endothelial cell proliferation, and migration. Treatment for DME generally involves primary management of DM, laser photocoagulation, and pharmacotherapeutics targeting mediators, namely, the anti-VEGF pathway. The emergence of anti-VEGF therapies has resulted in significant clinical improvements compared to laser therapy alone. However, multiple factors influencing the visual outcome after anti-VEGF treatment and the presence of anti-VEGF non-responders have necessitated the development of new pharmacotherapies. In this review, we explore the pathophysiology of DME and current management strategies. In addition, we provide a comprehensive analysis of emerging therapeutic approaches to the treatment of DME.

Outcomes in Sutured Versus Sutureless Wound Closure in Pediatric Cataract Surgery.

Abstract: PURPOSE To analyze the postoperative course, specifically postoperative complications, of pediatric patients who underwent cataract surgery by a single surgeon. The type of wound closure was compared to provide an evidence-based approach to surgical technique in pediatric cataract surgery. METHODS This retrospective study analyzed pediatric patients who underwent cataract extraction by a single surgeon from 2014 to 2020. Excluded from the study were patients with postoperative follow-up of less than 1 month. The primary outcome compared postoperative complications between patients with sutured and sutureless wound closure. Other outcomes analyzed included intraocular pressure, mean corrected distance visual acuity, and incidence of procedure needed to remove posterior capsule opacification. RESULTS The study comprised 116 eyes with sufficient follow-up; 86 had sutureless wound closure and 30 had sutured wound closure. An intraocular lens was placed in 52% of eyes in the sutureless group and in 80% of eyes in the sutured group. There was no statistically significant difference between preoperative and postoperative intraocular pressure between groups. The best corrected distance visual acuity was better in the sutured group at 6 months but not at the most recent follow-up visit. No cases of endophthalmitis were found in either group. There was no statistically significant difference between the incidence of retinal detachments and iris prolapse. CONCLUSIONS The incidence of endophthalmitis, retinal detachment, and iris prolapse was similar between pediatric patients who underwent cataract removal with sutureless versus sutured wound closure. Therefore, it may be reasonable to avoid the suture after pediatric cataract surgery. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Wing-pattern-specific effects of experience on mating behavior in Heliconius melpomene butterflies

Abstract: Many animals have the ability to learn, and some taxa have shown learned mate preference. This learning may be important for speciation in some species. The butterfly Heliconius melpomene is a model system for several areas of research, including hybridization, mate selection, and speciation, partially due to its widespread diversity of wing patterns. It remains unclear whether these butterflies can learn to prefer certain mates and if social experience shapes realized mating preferences. Here we test whether previous experience with a female influences male mate preference for two different H. melpomene subspecies, H. m. malleti and H. m. rosina. We conducted no-choice behavioral assays to determine if latency to court and whether males courted (vs no courtship) differed between naive males and males with previous exposure to a young, sexually mature, virgin female. To test whether assortative courtship preference is learned in H. melpomene, males were either paired with a female who shared their phenotype or one who did not. Naive H. m. malletti males courted assortatively, while naive H. m. rosina males did not. Experienced H. m. malleti males reduced their courting relative to naive males, suggesting that social experience with a sexually mature female that does not result in copulation may be perceived as a negative experience. In contrast, experienced H. m. rosina males exhibited similar courting rates to naive H. m. rosina males. Our results suggest that social experience can influence male mating behavior in H. melpomene and that behavioral plasticity may differ across populations in this species.

Aflibercept versus Faricimab in the Treatment of Neovascular Age-Related Macular Degeneration and Diabetic Macular Edema: A Review

Abstract: Diabetic macular edema (DME) and neovascular age-related macular degeneration (nAMD) are common retinal vascular diseases responsible for most blindness in the working-age and older population in developed countries. Currently, anti-VEGF agents that block VEGF family ligands, including ranibizumab, bevacizumab (off-label use), brolucizumab, and aflibercept, are the first-line treatment for nAMD and DME. However, due to the complex pathophysiological background of nAMD and DME, non-response, resistance during anti-VEGF therapy, and relapses of the disease are still observed. Moreover, frequent injections are a psychological and economic burden for patients, leading to inadequate adhesion to therapy and a higher risk of complications. Therefore, therapeutic methods are strongly needed to develop and improve, allowing for more satisfactory disease management and lower treatment burden. Currently, the Ang/Tie-2 pathway is a promising therapeutic target for retinal vascular diseases. Faricimab is the first bispecific monoclonal antibody for intravitreal use that can neutralize VEGF and Ang-2. Due to the prolonged activity, faricimab allows extending the interval between successive injections up to three or four months in nAMD and DME patients, which can be a significant benefit for patients and an alternative to implanted drug delivery systems.

Pediatric cataract surgery: considerations and updates in diagnosis and management

Abstract: Purpose of review The purpose of this review is to provide an overview of updates in the diagnosis and management of pediatric cataracts, with an emphasis on recent discoveries in the last two years. Recent findings Pediatric cataracts remain an infrequent but significant disease with vision threatening consequences. Although much of the management has not changed historically, more recent updates, particularly borrowed from adult cataract management, have influenced the field of cataract management in children. Even these studies emphasize that pediatric cataracts are a distinct clinical entity from adult-onset cataracts, and further research is needed to optimize the diagnosis and management of cataracts in childhood. Summary This is an overview of the recent advancements in the diagnosis of management of pediatric cataracts, with advancements that originate from the adult cataract surgery field in addition to studies that challenge classical surgical techniques to make cataract surgery safer and to promote amblyopia therapy.

Diabetes-related perturbations in the integrity of physiologic barriers.

Abstract: One of the hallmarks of health is the integrity of barriers at the cellular and tissue levels. The two cardinal functions of barriers include preventing access of deleterious elements of the environment (barrier function) while facilitating the transport of essential ions, signaling molecules and nutrients needed to maintain the internal milieu (transport function). There are several cellular and subcellular barriers and some of these barriers can be interrelated. The principal physiologic barriers include blood-retinal barrier, blood-brain barrier, blood-testis barrier, renal glomerular/tubular barrier, intestinal barrier integrity, pulmonary blood-alveolar barrier, blood-placental barrier and skin barrier. Tissue specific barriers are the result of the vasculature, cellular composition of the tissue and extracellular matrix within the tissue. Uncontrolled diabetes and acute hyperglycemia may disrupt the integrity of physiologic barriers, primarily through altering the vascular integrity of the tissues and may well contribute to the clinically recognized complications of diabetes. Although diabetes is a systemic disease, some of the organs display clinically significant deterioration in function while others undergo subclinical changes. The pathophysiology of the disruption of these barriers is not entirely clear but it may well be related to diabetes-related cellular stress. Understanding the mechanisms of diabetes related dysfunction of various physiologic barriers might help identifying novel therapeutic targets for reducing clinically significant complications of diabetes.

Development of a Computer System for Automatically Generating a Laser Photocoagulation Plan to Improve the Retinal Coagulation Quality in the Treatment of Diabetic Retinopathy

Abstract: In this article, the development of a computer system for high-tech medical uses in ophthalmology is proposed. An overview of the main methods and algorithms that formed the basis of the coagulation plan planning system is presented. The system provides the formation of a more effective plan for laser coagulation in comparison with the use of existing coagulation techniques. An analysis of monopulse- and pattern-based laser coagulation techniques in the treatment of diabetic retinopathy has shown that modern treatment methods do not provide the required efficacy of medical laser coagulation procedures, as the laser energy is nonuniformly distributed across the pigment epithelium and may exert an excessive effect on parts of the retina and anatomical elements. The analysis has shown that the efficacy of retinal laser coagulation for the treatment of diabetic retinopathy is determined by the relative position of coagulates and parameters of laser exposure. In the course of the development of the computer system proposed herein, main stages of processing diagnostic data were identified. They are as follows: the allocation of the laser exposure zone, the evaluation of laser pulse parameters that would be safe for the fundus, mapping a coagulation plan in the laser exposure zone, followed by the analysis of the generated plan for predicting the therapeutic effect. In the course of the study, it was found that the developed algorithms for placing coagulates in the area of laser exposure provide a more uniform distribution of laser energy across the pigment epithelium when compared to monopulse- and pattern-based laser coagulation techniques.

Pediatric cataract surgery: considerations and updates in diagnosis and management

Abstract: The purpose of this review is to provide an overview of updates in the diagnosis and management of pediatric cataracts, with an emphasis on recent discoveries in the last two years.Pediatric cataracts remain an infrequent but significant disease with vision threatening consequences. Although much of the management has not changed historically, more recent updates, particularly borrowed from adult cataract management, have influenced the field of cataract management in children. Even these studies emphasize that pediatric cataracts are a distinct clinical entity from adult-onset cataracts, and further research is needed to optimize the diagnosis and management of cataracts in childhood.This is an overview of the recent advancements in the diagnosis of management of pediatric cataracts, with advancements that originate from the adult cataract surgery field in addition to studies that challenge classical surgical techniques to make cataract surgery safer and to promote amblyopia therapy.