Eye Surface Research Articles

Dragonfly‐Inspired Compound Eye Lens with Biomimetic Structural Design

AbstractCompound eye biomimetics are extensively studied owing to their high level of functionality. However, optimizing material‐dependent parameters, such as refractive index, is essential for maximizing lens function. Therefore, metal films are deposited on Pantala flavescens compound eyes using a magnetic mirror magnetron cathode, which deposits films at low temperatures without plasma impingement. By increasing the thickness of the film on the compound eye surface, a compound eye mold is successfully fabricated with high heat tolerance. Lens fabrication is achieved using a high‐temperature‐curable resin. The resulting lens comprises numerous uniformly shaped functional units. This method offers a highly reproducible lens‐pouring molding technique using various materials, marking a significant advancement in developing imaging devices and sensors that accurately replicate the functionalities of dragonfly eyes.

Efficiency of infrared pyrometer and infrared thermography for assessing body surface temperature in hair sheep

The objectives of this study were: (i) to verify and compare the coat surface temperature (CST) of regions of interest (ROI) measured through infrared pyrometer (IRP) and thermography (IRT) under two environmental conditions, to evaluate (ii) reliability and (iii) sensitivity of the two infrared equipments to the environmental effect. Twenty hair ewes (Ovis aries), multiparous, non-lactating, non-pregnant, with body weight 59.38 ± 6.23 kg and body score condition ranging from 2.5 to 4.5 were evaluated. All CST, in both infrared methods, were higher (P < 0.001) in the afternoon (2 to 3 p.m.), with the exception of eyes surface temperature (TSEY) from IRT, which was higher (P < 0.001) in the morning (8 to 9 a.m.). Regarding the infrared methods at different times (twice a day, morning and afternoon), of the day, CST values for all ROIs were significantly higher (P < 0.001) in thermography, regardless of the time shift, except for ear pinna surface temperature (TSE) and rectum surface temperature (TSR), which showed no significant difference (P > 0.05) between the infrared methods during the morning shift. The thermal environment significantly influences (P < 0.001) the surface temperature of various anatomical regions in both infrared methods. The correlation coefficients between IRT and IRP were moderate. The IRT is more sensitive to the thermal environment, as it presented higher canonical coefficients in the environmental variables. Among surface temperatures, eye surface temperature is the most influenced by variables in the thermal environment, especially THI. All three methods (digital thermometer-DT, IRT and IRP) showed >80 % of the data variation in the first two components. Using the DT, we observed an association between vaginal temperature (VT) and RT with air temperature (AT) and temperature humidity index (THI), which was similar to the infrared thermography pattern, in which all ROIs were highly correlated with AT and THI. The opposite was observed in the pyrometer, in which an association between eye temperature and RH and lower factor loadings of the other ROIs with AT and THI in the first component was observed. In conclusion, while IRP and IRT showed similar performance in the morning, IRT proved to be more accurate in the afternoon, demonstrating a higher success rate in classifying the group of origin. Therefore, it is concluded that IRT is more reliable than IRP in detecting surface temperature changes under high temperatures.

Macrophage Membrane-Coated Nanoparticles for the Delivery of Natamycin Exhibit Increased Antifungal and Anti-Inflammatory Activities in Fungal Keratitis.

This study aims to explore the efficacy and safety of macrophage membrane-coated nanoparticles for the delivery of natamycin (NAT) in the therapy of fungal keratitis (FK). Macrophage membranes were isolated and identified by immunofluorescence staining (IFS). NAT was encapsulated into poly(lactic-co-glycolic acid) (PLGA). Fungal stimulated macrophage membranes (M1) or unstimulated membranes (M) were separately mixed and sonicated with PLGA nanoparticles. The biocompatible nanoparticles (PLGA-NAT, PLGA-NAT@M, and PLGA-NAT@M1) were characterized with zeta-sizer analysis, transmission electron microscopy (TEM), and Western blot. Drug encapsulation and loading efficiency and the release of NAT in the nanoparticles were detected by ultraviolet spectrophotometry. The cytotoxicity, ocular surface toxicity and irritability, and systemic safety of nanoparticles with different concentrations were assessed. In vitro, we examined the antifungal properties of the nanoparticles. The eye surface retention time, drug release, and curative effects on FK were evaluated in vitro and in vivo. IFS results showed the separation of the macrophage membrane and nucleus. The prepared nanoparticles had a typical "core-shell" structure and uniform nanometer size, and the membrane proteins were retained on the membrane allowing to exert functional effects of macrophage. The loading efficiencies of PLGA-NAT@M and PLGA-NAT@M1 were 7.6 and 6.7%, respectively. The encapsulation efficiencies of PLGA-NAT@M and PLGA-NAT@M1 were 51.2 and 41.5%, respectively. PLGA-NAT@M and PLGA-NAT@M1 could gradually release NAT and reduce the clearance of the ocular surface. Macrophage membranes enhanced the antifungal activity of PLGA-NAT. Furthermore, the membrane coated with macrophage increased the biocompatibility and decreased the corneal toxicity of nanoparticles. In vivo, PLGA-NAT@M1 significantly alleviated the severity of FK. In vitro, PLGA@M and PLGA@M1 reduced the protein levels of inflammatory cytokines after fungal stimulation. The prepared PLGA-NAT@M1 has good physical properties and biosafety. It could evade ocular surface clearance, release NAT gradually, and achieve high antifungal and anti-inflammatory efficiencies to FK. Macrophage membrane-coated nanoparticles clinically have high application potential to the treatment of FK.

Impact of Scleral Lenses on Visual Acuity and Ocular Aberrations in Corneal Ectasia: A Comprehensive Review.

Corneal ectasias, including keratoconus (KC), pellucid marginal degeneration (PMD), and post-LASIK ectasia, poses significant visual rehabilitation challenges due to the resultant irregular astigmatism, myopia, and higher-order aberrations (HOAs). These conditions often resist traditional corrective methods, necessitating advanced optical solutions. Scleral lenses (SLs) have emerged as a primary non-surgical option for managing these complex corneal irregularities. SLs form a smooth optical interface by forming a tear-filled chamber between the lens and the cornea, effectively mitigating HOAs and improving both high-contrast and low-contrast visual acuity (VA). This review evaluates the efficacy of SLs in enhancing VA and reducing aberrations in patients with corneal ectasia. It also explores the technological advancements in SLs, such as profilometry and wavefront-guided systems, which enable more precise and customized lens fittings by accurately mapping the eye's surface and addressing specific visual aberrations. The current body of evidence demonstrates that custom SLs significantly improve visual outcomes across various ectatic conditions, offering superior performance compared to conventional correction methods. However, challenges such as the complexity of fitting and the need for precise alignment remain. Ongoing innovations in SL technology and customization are likely to further enhance their clinical utility, solidifying their role as an indispensable tool in the management of corneal ectasias.

Development and evaluation of locust bean gum based in situ gel for ocular delivery of ofloxacin for treatment of bacterial keratitis

One of the drawbacks of conventional ocular dosage forms is their short residence time in the eye. To address this, we propose an ocular in situ gel that adheres to the eye surface for a prolonged period. Locust bean gum (LBG), a galactomannan polysaccharide, exhibits the desired characteristics to serve as a drug carrier for ocular application. However, the gum has not yet been investigated for ocular drug delivery. In this work, we have developed an LBG based in situ gel loaded with ofloxacin and evaluated its drug delivery efficacy through in vitro and ex vivo tests. To confer temperature sensitivity, LBG was grafted with N-isopropyl acrylamide (NIPAAm), and a series of solutions were made with ofloxacin (0.03 % w/v). The solution turned into a gel when the temperature was raised to 37 °C. The safety and efficacy of the developed in situ gels were validated through experiments on rat eyes infected with clinical strains of bacteria. The developed keratitis was completely healed indicating that the grafted LBG can be used as a potential candidate for the development of ocular in situ gel.

Axial length association with corneoscleral sagittal height and scleral asymmetry.

To determine how corneoscleral geometry changes with axial length and to assess the usefulness of including the sagittal configuration of the anterior segment when predicting the axial length. An observational study was performed including 96 healthy subjects (96 eyes). Axial length was calculated from optical biometry (IOL Master 500). Corneal curvature and scleral sagittal height parameters at 13, 14 and 15 mm were obtained automatically using corneoscleral topography (eye surface profiler; ESP). In addition, corneal and scleral sagittal heights at numerous locations (21 radii: 0-10 mm from the corneal apex at 12 angles: 0-330°) were calculated using the raw height data extracted from the ESP. The relationships between axial length and the study parameters were analysed using Pearson correlation analysis. The equations for the prediction of axial length were obtained by fitting multiple linear regression models. The temporal-nasal scleral asymmetry at 13-, 14- and 15-mm chord lengths was significantly correlated with axial length (r2 ≤ 0.26; p < 0.001). Significant inverse correlations were found between the temporal scleral sagittal height and axial length (r2 ≤ 0.28; p ≤ 0.02). The nasal scleral sagittal height was not associated with axial length. Three significant multiple linear regression models were fitted based on spherical equivalent, corneal radius and scleral asymmetry at 13 (r2 = 0.79; p < 0.001), 14 (r2 = 0.80; p < 0.001) and 15 (r2 = 0.80; p < 0.001) mm chord lengths. Larger ocular globes show reduced temporal-nasal scleral asymmetry, mainly due to the lower sagittal height of the temporal sclera. Thus, the geometry of the temporal scleral may be a factor of interest during myopia progression.

Simple limbal epithelial transplantation versus cultivated limbal epithelial transplantation in ocular burns

PurposeTo compare the outcomes of simple limbal epithelial transplantation (SLET) with cultivated limbal epithelial transplantation (CLET) for the management of total limbal stem cell deficiency (LSCD) in eyes with unilateral ocular burns. DesignRandomized controlled trial. Methods100 patients (100 eyes) with unilateral total LSCD following ocular burns undergoing autologous Limbal Stem Cell Transplantation (LSCT) were enrolled and randomized into SLET and CLET groups. Restoration of an epithelized ocular surface was the primary outcome measure. Occurrences of progressive conjunctivalization and persistent epithelial defects postoperatively were considered surgical failures. ResultsMean age was 20.2 ± 13.1 years (SLET) and 22.6 ± 14.3 years (CLET) (p = 0.363). Alkali burn was the most common causative factor in both groups and had comparable mean logMAR BCVA at presentation [SLET: 2.33 ± 0.5, CLET: 2.23 ± 1.48 (p = 0.652)]. Median time interval between injury and surgical intervention was 18 months (SLET) and 12 months (CLET) (p = 0.06). 88 % eyes in SLET group maintained a stable ocular surface at 1 year period versus CLET group (86 %) (p = 0.999). Mean logMAR BCVA significantly improved in both groups with SLET having significantly better BCVA versus CLET at 6 months (p = 0.0390), 1 year (p = 0.0001), 2 year (p = 0.0001) and 3 years (p = 0.0001) follow up. Kaplan-Meier survival analysis was statistically insignificant amongst the 2 groups (p = 0.590). ConclusionsCompared to CLET, SLET is equally efficacious in restoring and maintaining a stable ocular surface in eyes with total LSCD due to ocular burns, with the added advantage of providing superior visual outcomes.

Empowering vision: the impact of nursing-led educational program on patients with dry eye syndrome

BackgroundDry eye syndrome (DES) is a widespread ocular condition affecting the general population. It is a complex disorder affecting the eye surface, characterized by a tear film imbalance and ocular symptoms such as eye ache, burning, irritation, dryness, blurred vision, and foreign body sensation. DES can reduce visual acuity, increase the risk of ocular infection, and significantly impact daily activities and quality of life.AimDetermine the impact of nursing-led educational program on the management of DES and patients’ health outcomes including the intensity of DES symptoms and their influence on visual-related functions.MethodsThe study was conducted with a quasi-experimental design. Sixty adult patients diagnosed with DES were selected using a convenience sampling method. Two tools were employed for the collection of data. Tool I: Precipitating factors of DES structured interview schedule. Tool II: Ocular surface disease index (OSDI) to assess ocular irritation symptoms associated with DES and their effect on functions related to vision.ResultsA statistically significant decrease in the mean scores of OSDI in the study group two weeks after the implementation of the educational program regarding the ocular symptoms, functions associated with vision, environmental triggers, and overall score of OSDI.ConclusionImplementing an educational program for DES is effective in relieving symptoms, boosting patients’ understanding of managing symptoms effectively, and maintaining eye health. Therefore, patients must be instructed on dry eye early detection and management to enhance health-related outcomes and self-care practices.RegistrationClinicalTrials.gov: NCT06288945.

Hydrogels as a Potential Biomaterial for Multimodal Therapeutic Applications.

Hydrogels, composed of hydrophilic polymer networks, have emerged as versatile materials in biomedical applications due to their high water content, biocompatibility, and tunable properties. They mimic natural tissue environments, enhancing cell viability and function. Hydrogels' tunable physical properties allow for tailored antibacterial biomaterial, wound dressings, cancer treatment, and tissue engineering scaffolds. Their ability to respond to physiological stimuli enables the controlled release of therapeutics, while their porous structure supports nutrient diffusion and waste removal, fostering tissue regeneration and repair. In wound healing, hydrogels provide a moist environment, promote cell migration, and deliver bioactive agents and antibiotics, enhancing the healing process. For cancer therapy, they offer localized drug delivery systems that target tumors, minimizing systemic toxicity and improving therapeutic efficacy. Ocular therapy benefits from hydrogels' capacity to form contact lenses and drug delivery systems that maintain prolonged contact with the eye surface, improving treatment outcomes for various eye diseases. In mucosal delivery, hydrogels facilitate the administration of therapeutics across mucosal barriers, ensuring sustained release and the improved bioavailability of drugs. Tissue regeneration sees hydrogels as scaffolds that mimic the extracellular matrix, supporting cell growth and differentiation for repairing damaged tissues. Similarly, in bone regeneration, hydrogels loaded with growth factors and stem cells promote osteogenesis and accelerate bone healing. This article highlights some of the recent advances in the use of hydrogels for various biomedical applications, driven by their ability to be engineered for specific therapeutic needs and their interactive properties with biological tissues.

Factors Defining Density of Retinal Macrophage-like Cells Displayed with Optical Coherence Tomography.

To study the factors which define the density of MLC of the inner retinal surface in healthy eyes. Healthy individuals, including candidates for LASIK surgery, and post-LASIK patients were included. MLC density was calculated using structural en face projections of OCT angiography scans. The status of the vitreoretinal interface was assessed as the distance from the inner limiting membrane to the posterior hyaloid membrane on cross-sectional scans and as the area of tight posterior vitreous adhesion on en face projections. The correlation between MLC density and various demographic and anatomical parameters, including the status of the vitreoretinal interface was calculated. Fifty-four healthy individuals, 30 post-LASIK patients all without posterior vitreous detachment (PVD) as well as 20 patients with partial PVD were included. MLC density showed a statistically significant correlation with axial length, refractive error, age, subfoveal choroidal thickness, and the status of the vitreoretinal interface (p<0.05) in eyes without PVD. In multiple regression analysis the axial length was the main parameter independently correlated with MLC density (p=0.025). The status of the vitreoretinal interface had a statistically significant correlation with the axial length (p<0.001). Partial PVD was associated with almost complete loss of MLC (p<0.001). The status of the vitreoretinal interface is a characteristic directly defining the density of retinal MLC in healthy eyes. However, axial length appears to be a key anatomical parameter which correlates with MLC density due to its effects on the adhesion of the posterior hyaloid membrane to the retinal surface.

Sex-dependent differential increase of specialized pro-resolving mediators in extracellular vesicles secreted by human primary conjunctival goblet cells during allergic inflammation

AimsConjunctival epithelium lines the inside of the eyelids and covers the sclera, thus providing stability to the eye surface. Goblet cells in conjunctival epithelium (CjGCs) are well known for their mucin-secretion function, which wet and protect the ocular surface, but other aspects are still not well understood. To expand our understanding beyond their mucin-secreting function, we investigated CjGC-secreted extracellular vesicles (EVs) and lipid mediators therein. Materials and methodsUsing histamine-mediated allergic inflammation in human primary CjGCs (HCjGCs) as a disease model, we quantified using ELISA a proinflammatory mediator PGE2 and two specialized pro-resolving mediators (SPMs) LXA4 and RvD1 in EVs secreted during allergic inflammation. Key findingsAt 18 h post histamine stimulation, the amount of LXA4 and RvD1 in EVs was notably higher compared to those in unstimulated. Interestingly, this increase was only observed in female EVs but not in males. The mean fold increase of LXA4 and RvD1 in female EVs was 3.9 and 3.4, respectively, but it was only 0.9 and 1.0 in male EVs. Supplying docosahexaenoic acid (DHA, the source of RvD1 and other SPMs) to the culture medium during the allergic inflammation resulted in even higher mean fold increase of 5.3 and 6.9 for LXA4 and RvD1 in female EVs, respectively, but it was only 0.5 and 0.8 in male EVs. SignificanceWe conclude that HCjGCs show a clear sex difference in allergic response. Our results may also provide a new insight into the male predisposition to severe forms of allergic conjunctivitis and potential improvement in disease care in the clinic.

Epidemiology of Common Eye Diseases in North Kordofan, Sudan

Introduction: Eye illness epidemiology is critical because it identifies the most dangerous diseases in the community and helps decision-makers make better management decisions. This study aims to explore the epidemiology of prevalent eye diseases in north Kordofan State. Methodology: This retrospective descriptive study was conducted at El-Obeid Teaching Hospital's Ophthalmology Department, North Kordofan State, Sudan, and Dr. Khalil's Ophthalmology Center. Out of almost 50000 patient files, we selected 1000 files for this study using a random systemic selection of 1 in 50. The data collection sheet was created, and all data were collected. Results: The corneal diseases made up 19.6% of the 1000 cases in this study, followed by conjunctival 17.7%, lens 15.3%, eye surface 9.8%, uveal tract 9.1%, refractive errors 6.4%, eye lids 5.4%, orbital 5.4%, glaucoma 4.3%, retinopathy 4.6%, anterior chamber diseases 2.1%, lacrimal drainage system disorders 1.8%, and nerve palsies 0.5%. Conclusion: The western Sudan is heavily affected by eye diseases, with corneal diseases being the most common, closely followed by conjunctival diseases. This report delves into the eye disease situation in western Sudan. With absence of such literature from Sudan, the findings of this study presenting baseline of future research in this context.

The Effect of Face Mask Wear on the Ocular Surface and Contact Lens Microbiome.

As face mask wear can result in the redirection of nasal and oral exhalation toward the ocular region, this study investigated the impact of face mask wear on the conjunctiva, eyelid margin, and contact lens (CL) surface microbiome. In this prospective, cross-over study, experienced CL wearers (N=20) were randomized to wear a face mask for 6 hr/day (minimum) for a week or no mask for a week. The conjunctiva, eyelid, and CLs were then sampled. After a 1-week washout period, participants were crossed over into the alternate treatment for 1 week and sampling was repeated. Sampling was bilateral and randomly assigned to be processed for culturing or 16S ribosomal(r) RNA gene sequencing. Culturing showed no effect of mask wear on the average number of bacterial colonies isolated on the conjunctiva, eyelid, or CL, but there was increased isolation of Staphylococcus capitis on CL samples with mask wear (P=0.040). Culture-independent sequencing found differences in the taxonomic complexity and bacterial composition between the three sites (P<0.001), but there was no effect of bacterial diversity within and between sites. Mask wear did not impact dry eye or CL discomfort, but increased ocular surface staining was reported (P=0.035). Mask wear did not substantially alter the microbiome of the conjunctiva, eyelid margin, or CL surfaces in uncompromised healthy eyes.

Clinical characteristics and viral colonization of corneal donors with coronavirus disease 2019: a comprehensive analysis before and after corneal transplantation

Purpose To evaluate the clinical characteristics and viral Colonization of corneas donated by volunteers with coronavirus disease 2019 (COVID-19) before and after corneal transplantation. Methods We retrospectively compared the characteristics and clinical outcomes of patients who received corneas from donors with and without a history of COVID-19 after corneal transplantation. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to evaluate the expression of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA on ocular surfaces in corneal preservation solutions as well as the recipients’ tears. Immunofluorescence was also performed to evaluate the expression of viral spike proteins in the corneas. Intraocular pressure (IOP) measurement, optical coherence tomography (OCT), and slit-lamp inspection at each follow-up examination were performed to assess the surgical efficacy. Results The RT-PCR results of eye surface swabs before corneal extraction, the corneal preservation solutions before transplantation as well as the recipients’ tears were negative, thereby indicating the suitability for transplantation. No significant differences in IOP measurements, OCT findings, or in the incidence of post transplantation complications were observed between donors with and without COVID-19. Conclusions Corneal transplantation using corneas from COVID-19 infected donors does not alter clinical outcomes when compared to controls receiving corneas from non-infected donors.

Refugee child vision screening curriculum for multidisciplinary trainees

Background: Conflicts, natural disasters, and persecution have led to growing refugee populations worldwide. Vision impairment within these populations is a significant concern. Eye conditions in refugee children appear to peak during times of resettlement. Future medical and nursing professionals need to be trained to detect treatable conditions that could lead to permanent vision loss and significant morbidity if undiagnosed. While curricula regarding refugee health exist, no curriculum exists on identifying common eye conditions in refugee children and performing pediatric eye screening. Methods: We created and delivered a virtual, single-session curriculum on pediatric refugee eye conditions and screening to medical and nursing trainees. A needs assessment survey assessing trainees’ knowledge and confidence in detecting eye conditions in children and refugees informed curriculum design. Pre- and post-test assessments evaluated participants’ knowledge and confidence before and after the module. A two-sided signed-rank test was used to compare pre- and post-test scores. Results: Twenty-seven respondents completed the needs assessment survey, which revealed low levels of confidence in performing vision screening, especially in evaluating the eye surface. Fourteen participants completed the module and pre- and post-test surveys. Mean knowledge test score improved from 52% to 75% (P&lt;0.001). Discussion: As the global refugee population grows, this study supports the value of incorporating a refugee child eye curriculum into trainee education to empower providers to detect and address refugee eye conditions.

Blinded by smoke: Wildfire smoke exposure and eye irritation in australian wildland firefighters

PurposeWildfire occurrence is increasing worldwide, putting firefighters and general public at increased risk of eye injuries from smoke exposure. This study explored ocular symptoms and use of protective eyewear amongst wildland firefighters in Australia. MethodsAustralian wildland firefighters were invited to complete an online survey about the occurrence of eye irritation, use of protective eyewear and behaviours associated with occupational smoke exposure. Responses were analysed using logistic regression and qualitative inductive content analysis. Results338 wildland firefighters completed the survey. Eye irritation was reported by 90 % of firefighters at least sometimes during work and by 70 % after work. Frequency of eye irritation was greater amongst females than males (OR 2.01, CI 1.22–3.31, p < 0.001). Protective eyewear was used often or always by 67 % of firefighters on the fireground, however 55 % had to remove their protective eyewear due to sweat, fogging or another reason. Goggles were more likely to be removed compared to sunglasses and safety glasses (OR 4.28, CI 2.75–6.68, p < 0.001).Firefighters reported that, at times smoke exposure necessitated eye closure and impaired vision on the fireground. Firefighters also reported that protective eyewear helped to reduce eye symptoms, but its consistent use on the fireground was difficult. The severity and recovery from eye symptoms varied between participants. ConclusionAustralian wildland firefighters frequently experience eye irritation from smoke exposure, and this can affect operational capabilities. These findings can support the development of evidence-based strategies to help protect and aid recovery of the eye surface following smoke exposure.

The ion channel TRPM8 is a direct target of the immunosuppressant rapamycin in primary sensory neurons.

The mechanistic target of rapamycin (mTOR) signalling pathway is a key regulator of cell growth and metabolism. Its deregulation is implicated in several diseases. The macrolide rapamycin, a specific inhibitor of mTOR, has immunosuppressive, anti-inflammatory and antiproliferative properties. Recently, we identified tacrolimus, another macrolide immunosuppressant, as a novel activator of TRPM8 ion channels, involved in cold temperature sensing, thermoregulation, tearing and cold pain. We hypothesized that rapamycin may also have agonist activity on TRPM8 channels. Using calcium imaging and electrophysiology in transfected HEK293 cells and wildtype or Trpm8 KO mouse DRG neurons, we characterized rapamycin's effects on TRPM8 channels. We also examined the effects of rapamycin on tearing in mice. Micromolar concentrations of rapamycin activated rat and mouse TRPM8 channels directly and potentiated cold-evoked responses, effects also observed in human TRPM8 channels. In cultured mouse DRG neurons, rapamycin increased intracellular calcium levels almost exclusively in cold-sensitive neurons. Responses were markedly decreased in Trpm8 KO mice or by TRPM8 channel antagonists. Cutaneous cold thermoreceptor endings were also activated by rapamycin. Topical application of rapamycin to the eye surface evokes tearing in mice by a TRPM8-dependent mechanism. These results identify TRPM8 cationic channels in sensory neurons as novel molecular targets of the immunosuppressant rapamycin. These findings may help explain some of its therapeutic effects after topical application to the skin and the eye surface. Moreover, rapamycin could be used as an experimental tool in the clinic to explore cold thermoreceptors.

Ocular Manifestations in Seborrheic Dermatitis Epidemiology, Clinical Features, and Management: A Comprehensive Review.

Seborrheic dermatitis (SD) often leads to ocular manifestations (OM) that are frequently overlooked. This study comprehensively explains the genesis of these ocular issues, which involves a combination of Malassezia overgrowth, changes in sebum production, and inflammatory responses in the body. The periocular region is rich in sebaceous glands, allowing Malassezia to thrive, which can lead to an inflammatory reaction that spreads to the eye surface, causing disorders such as blepharitis, conjunctivitis, keratitis, and ocular surface diseases. Although epidemiological data are limited, it is well established that ocular involvement occurs in approximately 10%-40% of individuals with SD. Early detection and treatment are crucial to prevent potential vision-threatening complications. A comprehensive diagnostic approach is necessary, including clinical examination, slit-lamp biomicroscopy, tear film analysis, and corneal imaging. Managing these conditions requires a multidisciplinary strategy involving collaboration between dermatologists and ophthalmologists. The treatment should involve topical and systemic medications to address the skin and ocular components. Patient education is critical for improving adherence to therapy, self-management, and the early identification of problems. In the future, it will be essential to investigate the intricate interactions between Malassezia species and host immunological processes. This collective effort will involve creating new biomarkers and diagnostic tools, investigating targeted immunomodulatory drugs and novel lipid-based medicines as potential treatments, and conducting large-scale longitudinal studies to understand the epidemiological patterns and prognostic variables better. By raising awareness, encouraging collaboration across disciplines, and advancing research, healthcare practitioners can significantly improve patients' quality of life with SD and OM.

Formulation and Development of Nanofiber-Based Ophthalmic Insert for the Treatment of Bacterial Conjunctivitis.

A novel ophthalmic delivery system utilizing levofloxacin-loaded, preservative-free, nanofiber-based inserts was investigated. Polyvinyl alcohol (PVA) and Poloxamer 407 (Polox)were employed as matrix materials, while hydroxypropyl-beta-cyclodextrin (HP-β-CD) was a solubilizer. The formulations were prepared via electrospinning and characterized for fiber morphology, drug dissolution, cytotoxicity, and antimicrobial activity. Scanning electron microscopy confirmed uniform fibrous structures. Fourier Transform Infrared spectroscopy and X-ray diffraction analyses demonstrated the amorphous state of levofloxacin within the fibers. In vitro dissolution studies revealed a rapid (within 2 min) and complete drug release, with higher HP-β-CD levels slightly delaying the release. Cytotoxicity tests showed increased HP-β-CD concentrations induced irritation, that was mitigated by sodium hyaluronate. The antimicrobial efficacy of the nanofibers was comparable to conventional eye drops, with lower minimum inhibitory concentrations for most tested strains. The nanofibrous formulation prepared from a PVA-Polox-based viscous solution of the drug:CD 1:1 mol ratio, containing 0.4% (w/w) sodium hyaluronate) was identified as a particularly promising alternative formulation due to its rapid and complete dissolution, good biocompatibility, and effective antimicrobial properties. Its gelling properties indicate that the residence time on the eye surface can be increased, potentially reducing discomfort and enhancing therapeutic outcomes. The nanofibrous formulations enhanced antimicrobial efficacy, providing a preservative-free alternative that minimizes the potential eye irritation that might occur because of the preservative agent and reduces the administrated dose frequency by extending the drug's retention time on the eye's surface. Subsequently, it improves patients' adherence, which would reflect positively on the bioavailability. The levofloxacin-HP-β-CD nanofibers demonstrate promise as an alternative to traditional eye drops, offering advantages in solubility, stability, and patient compliance for ocular infection treatment.

Inside Back Cover: Cornea‐SELEX for aptamers targeting the surface of eyes and liposomal drug delivery (EXP2 4/2024)

Inside Back Cover: Cornea‐SELEX for aptamers targeting the surface of eyes and liposomal drug delivery (EXP2 4/2024)