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Topic Review
Diabetic Retinopathy Treatment
Diabetic retinopathy (DR) is one of the leading matters of vision-loss globally. Even though there have been extensive efforts to reduce vision loss, the prevalence of DR is still uprising. There are several pharmacological and surgical therapies currently used in clinics, but none of them has not been used as effective therapies at the early stage of DR.
  • 1.1K
  • 01 Nov 2021
Topic Review
Medication for Macular Degeneration
Age-related macular degeneration (AMD) is central vision loss with aging, was the fourth main cause of blindness in 2015, and has many risk factors, such as cataract surgery, cigarette smoking, family history, hypertension, obesity, long-term smart device usage, etc. In general, AMD drug candidates from natural products are more effective at treating early and intermediate AMD.
  • 1.1K
  • 05 Nov 2021
Topic Review
Retinal Ganglion Cell Distress
Retinal ganglion cells (RGCs) are a population of neurons of the central nervous system (CNS) extending with their soma to the inner retina and with their axons to the optic nerve. Glaucoma represents a group of neurodegenerative diseases where the slow progressive death of RGCs results in a permanent loss of vision. To date, although Intra Ocular Pressure (IOP) is considered the main therapeutic target, the precise mechanisms by which RGCs die in glaucoma have not yet been clarified.
  • 1.1K
  • 09 Oct 2021
Topic Review
Pituitary Adenylate Cyclase-Activating Polypeptide Role in the Eye
Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) is a neuropeptide with widespread distribution throughout the central and peripheral nervous system as well as in many other peripheral organs. It plays cytoprotective effects mediated mainly through the activation of specific receptors. PACAP is known to play pleiotropic effects on the eye, including the cornea, protecting it against different types of insult. 
  • 1.1K
  • 18 Jan 2022
Topic Review
Retinal Vasculitis
Retinal vascular diseases have distinct, complex and multifactorial pathogeneses yet share several key pathophysiological aspects including inflammation, vascular permeability and neovascularisation. In non-infectious posterior uveitis (NIU), retinal vasculitis involves vessel leakage leading to retinal enlargement, exudation, and macular oedema. Neovascularisation is not a common feature in NIU, however, detection of the major angiogenic factor—vascular endothelial growth factor A (VEGF-A)—in intraocular fluids in animal models of uveitis and patient samples may be an indication for a role for this cytokine in a highly inflammatory condition. Suppression of VEGF-A by directly targeting the leukotriene B4 (LTB4) receptor (BLT1) pathway indicates a connection between leukotrienes (LTs), which have prominent roles in initiating and propagating inflammatory responses, and VEGF-A in retinal inflammatory diseases.
  • 1.0K
  • 22 Sep 2021
Topic Review
Ocular Delivery of Therapeutic Proteins
Therapeutic proteins, including monoclonal antibodies, single chain variable fragment (ScFv), crystallizable fragment (Fc), and fragment antigen binding (Fab), have accounted for one-third of all drugs on the world market. In particular, these medicines have been widely used in ocular therapies in the treatment of various diseases, such as age-related macular degeneration, corneal neovascularization, diabetic retinopathy, and retinal vein occlusion. The formulation of these biomacromolecules is challenging due to their high molecular weight, complex structure, instability, short half-life, enzymatic degradation, and immunogenicity, which leads to the failure of therapies. Various efforts have been made to overcome the ocular barriers, providing effective delivery of therapeutic proteins, such as altering the protein structure or including it in new delivery systems. These strategies are not only cost-effective and beneficial to patients but have also been shown to allow for fewer drug side effects. Researchers discuss several factors that affect the design of formulations and the delivery of therapeutic proteins to ocular tissues, such as the use of injectable micro/nanocarriers, hydrogels, implants, iontophoresis, cell-based therapy, and combination techniques. In addition, other approaches are briefly discussed, related to the structural modification of these proteins, improving their bioavailability in the posterior segments of the eye without affecting their stability. Future research should be conducted toward the development of more effective, stable, noninvasive, and cost-effective formulations for the ocular delivery of therapeutic proteins. In addition, more insights into preclinical to clinical translation are needed.
  • 1.0K
  • 18 Jan 2023
Topic Review
Age-Related Macular Degeneration and the Complement System
Age-related macular degeneration (AMD) is a progressive degenerative disease of the central retina and the leading cause of severe loss of central vision in people over age 50. Patients gradually lose central visual acuity, compromising their ability to read, write, drive, and recognize faces, all of which greatly impact daily life activities. Quality of life is significantly affected in these patients, and there are worse levels of depression as a result. AMD is a complex, multifactorial disease in which age and genetics, as well as environmental factors, all play a role in its development and progression. The mechanism by which these risk factors interact and converge towards AMD are not fully understood, and therefore, drug discovery is challenging, with no successful therapeutic attempt to prevent the development of this disease.
  • 1.0K
  • 24 May 2023
Topic Review
Treatment for Central Serous Chorioretinopathy
Central serous chorioretinopathy (CSC) is a controversial disease both in terms of clinical classification and choice of therapeutic strategy. Choroidal layers, retinal pigment epithelium (RPE), photoreceptors, and retina are involved to varying degrees. 
  • 1.0K
  • 18 Mar 2021
Topic Review
Role of Neutrophils on the Ocular Surface
Neutrophils are considered short-term and terminally differentiated phagocytes with no significant gene expression or regulatory role in adaptive immunity. However, in recent years, opinions on the role of neutrophils have been developing. Neutrophils are primarily short-term polymorphonuclear cells (PMNs) related with the first line combatant to pathogens, which can phagocytose potentially harmful antigens and trigger strong antimicrobial defenses, including the release of reactive oxygen species (ROS) such as superoxide and neutrophil extracellular traps.
  • 1.0K
  • 11 Oct 2021
Topic Review
Anatomy and Barriers of Ocular Drug Delivery
Ocular diseases profoundly impact patients’ vision and overall quality of life globally. However, effective ocular drug delivery presents formidable challenges within clinical pharmacology and biomaterial science, primarily due to the intricate anatomical and physiological barriers unique to the eye.
  • 1.0K
  • 13 Nov 2023
Topic Review
Adipose Stem Cells in Modern-Day Ophthalmology
Stem cells (SCs) have evolved as an interesting and viable factor in ophthalmologic patient care in the past decades. SCs have been classified as either embryonic, mesenchymal, tissue-specific, or induced pluripotent cells. Multiple novel management techniques and clinical trials have been established to date. While available publications are predominantly animal-model-based, significant material is derived from human studies and case-selected scenarios. This possibility of explanting cells from viable tissue to regenerate/repair damaged tissue points to an exciting future of therapeutic options in all fields of medicine, and ophthalmology is surely not left out. Adipose tissue obtained from lipo-aspirates has been shown to produce mesenchymal SCs that are potentially useful in different body parts, including the oculo-visual system.
  • 1.0K
  • 18 Apr 2023
Topic Review
Conjunctival Melanoma and its Therapies
Conjunctival melanoma (CM) is a rare ocular disease, accounting for about 2% of all ocular malignancies. Its incidence has been increasing in recent years, with 0.3–0.8 cases per million people in Western countries, mainly in Caucasian ethnicity, but can occur in African or in Afro-Americans as well. It most commonly appears in middle-aged or elderly white individuals. In the US, the incidence increased by 295% from 1973 to 1999.
  • 1.0K
  • 25 Jan 2021
Topic Review
Protein Analysis of Gene Mutations in Conjunctival Melanoma
Genetics is the basis of many neoplasms, including conjunctival melanoma (CM). Here, we analyzed five proteins associated with CM, namely BRAF, NRAS, c-KIT, NF1, and PTEN and investigated structures of BRAF, NRAS, c-KIT, and PTEN generated with AlphaFold, and NF1 structure from the Protein Databank (PDB). The Predictor of Natural Disordered Protein Regions (PONDR®), the web server for the prediction of intrinsically unstructured regions of proteins (IUPred), and the mean disorder profile (MDP) were utilized to analyze each protein for intrinsically disordered protein regions (IDPRs). AlphaFold and PDB structures show the presence of IDPRs in all five proteins. The bioinformatics analysis confirmed high levels of disorder in these proteins, with most disordered being BRAF (45.95%), followed by PTEN (31.76%), NF1 (22.19%), c-KIT (21.82%), and NRAS (14.81%). Our STRING analysis found that each of these five proteins had more predicted interactions then expected (p-value < 1.0 × 10−16). Our analysis demonstrates that the mutations linked to CM likely affected IDPRs and possibly altered their highly complex PPIs. Quantifying IDPRs in BRAF, NRAS, c-KIT, NF1, and PTEN and understanding these protein regions are important processes as IDPRs can be possible drug targets for novel targeted therapies for treating CM.
  • 999
  • 21 Oct 2021
Topic Review
Nutritional Factors in Glaucoma and Ophthalmologic Pathologies
Glaucoma is a chronic optic neuropathy that can lead to irreversible functional and morphological damage if left untreated. The gold standard therapeutic approaches in managing patients with glaucoma and limiting progression include local drops, laser, and/or surgery, which are all geared at reducing intraocular pressure (IOP). Nutrients, antioxidants, vitamins, organic compounds, and micronutrients have been gaining increasing interest as integrative IOP-independent strategies to delay or halt glaucomatous retinal ganglion cell degeneration. 
  • 997
  • 09 May 2023
Topic Review
Interleukin-6 and Macular Edema
The role of IL-6 in the development of macular edema has been well elucidated. IL-6 is produced by multiple cells of the innate immune system and leads to a higher likelihood of developing autoimmune inflammatory diseases, such as non-infectious uveitis, through a variety of mechanisms. These include increasing the helper T-cell population over the regulatory T-cell population and leading to the increased expression of inflammatory cytokines, such as tumor necrosis factor-alpha.
  • 997
  • 09 Jun 2023
Topic Review
Wavefront Sensors and Aberration Sensors in Ophthalmology
The wavefront sensor is one of the main elements of the adaptive vision correction system. Its task is to measure the aberrations of the wavefront and transmit the results of these measurements to the processing device. The main causes of wavefront aberrations in the eye are the shape and optical properties of the cornea, pupil and lens. In modern diagnostic devices, wave aberrations are described in terms of Zernike polynomials (OSA and ANSI standards). Nowadays, there are a wide variety of wavefront sensors.
  • 984
  • 02 Jan 2024
Topic Review
Application of Different Biodegradable Ocular Drug Delivery Systems
The complex nature of the ocular drug delivery barrier presents a significant challenge to the effective administration of drugs, resulting in poor therapeutic outcomes. To address this issue, it is essential to investigate new drugs and alternative delivery routes and vehicles. One promising approach is the use of biodegradable formulations to develop potential ocular drug delivery technologies. These include hydrogels, biodegradable microneedles, implants, and polymeric nanocarriers such as liposomes, nanoparticles, nanosuspensions, nanomicelles, and nanoemulsions. 
  • 976
  • 09 Mar 2023
Topic Review
Suitability Prediction for Corneal Donorship
In Germany, more than one-third of donor corneas harvested are not suitable for transplantation. We evaluated the factors associated with the usability of donor corneas. Method: Data from 2032 consecutive donor corneas harvested at the Rhineland-Palatinate Eye Bank in Mainz, Germany, were retrospectively analyzed. Factors of interest were age, sex, lens status, cause of death, cardiopulmonary resuscitation (CPR), death-to-explantation-interval (DEI), and the influence of these factors on the proportion of discarded donor corneas. Factors associated with endothelial cell density (ECD) were analyzed in a linear regression mixed model. Results: Higher donor age, male gender, pseudophakic lens status, and longer DEI were associated with significantly reduced ECD. With respect to DEI, the estimated cell loss was 7 ± 2 cells/mm2/hour (p < 0.001). Age was associated with a lower ECD of 6 ± 2 cells/mm2 per year (p = 0.001). Female ECD was 189 ± 44 cells/mm2 higher than male ECD (p < 0.001). Pseudophakic eyes had 378 ± 42 cells/mm2 less compared with phakic eyes (p < 0.001). Cause of death did not affect the ECD. Of note, 55% and 38% of corneas harvested on the second and third postmortem day, respectively, and 45% of corneas from donors older than 80 years were still suitable for transplantation. In the context of a growing need for donor corneas, we do not recommend limiting donor age and collection time to 24 h or excluding oncology donors, as is the practice in many countries. Therefore, we propose a mathematical model for better donor preselection. 
  • 970
  • 10 Aug 2021
Topic Review
Dry Eye Syndrome
Dry eye syndrome (DES) results from insufficient tear production or excessive evaporation of tears, and is associated with symptoms such as dry eye surface, discomfort, visual impairment, and aching. It also leads to an increase in the osmolality of the tear film and inflammation of the ocular surface. The prevalence of DES is estimated as 5–30% in people older than 50 years.
  • 968
  • 22 Apr 2021
Topic Review
Surgical Temporary Ocular Discomfort Syndrome
The term STODS (Surgical Temporary Ocular Discomfort Syndrome) has been coined to describe the ocular surface perturbations induced by surgery. As one of the most important refractive elements of the eye, Guided Ocular Surface and Lid Disease (GOLD) optimization is fundamental to success in achieving refractive outcomes and mitigating STODS. Effective GOLD optimization and the prevention/treatment of STODS requires an understanding of the molecular, cellular, and anatomic factors that influence ocular surface microenvironment and the associated perturbations induced by surgical intervention. 
  • 968
  • 08 Mar 2023
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