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Carbon quantum dots (CQDs), an emerging nanomaterial, are gaining attention in ophthalmological applications due to their distinctive physical, chemical, and biological characteristics. For example, their inherent fluorescent capabilities offer a novel and promising alternative to conventional fluorescent dyes for ocular disease diagnostics. Furthermore, because of the excellent biocompatibility and minimal cytotoxicity, CQDs are well-suited for therapeutic applications. In addition, functionalized CQDs can effectively deliver drugs to the posterior part of the eyeball to inhibit neovascularization. This review details the use of CQDs in the management of ophthalmic diseases, including various retinal diseases, and ocular infections. While still in its initial phases within ophthalmology, the significant potential of CQDs for diagnosing and treating eye conditions is evident. [ABSTRACT FROM AUTHOR]

Introduction: Often associated with contact lens wear, Acanthamoeba keratitis is an extremely painful blinding infection that has remained significant despite advances in drug discovery and chemotherapies. Current treatment is intricate and demands early diagnosis, aggressive and prolonged application, and may result in infection recurrence. The latter is due to the ability of the parasite to undergo cellular differentiation and transform into a resistant cyst form or infective trophozoite form. Areas covered: Here, we present a review of our current understanding of emerging therapies and priorities tackling Acanthamoeba keratitis. Literature searches were carried out using bibliographic databases and results sifted and reviewed to present recent findings, challenges and novel opportunities in the development of therapeutic interventions and/or preventative measures against Acanthamoeba keratitis. Expert opinion: Nanomedicine-based theranostics to combine diagnosis and treatment of Acanthamoeba keratitis offer remarkable opportunity in the development of clinical applications in the management of Acanthamoeba keratitis. [ABSTRACT FROM AUTHOR]

We report a case of a 53-year-old HIV-negative patient in San Francisco, California, USA, with no classic mpox prodromal symptoms or skin lesions who experienced fulminant, vision-threatening scleritis, keratitis, and uveitis. Deep sequence analysis identified monkeypox virus RNA in the aqueous humor. We confirmed the virus on the cornea and sclera by PCR.

AIM: To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs. METHODS: The clinical data of 155 patients were retrospectively collected in this study, and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed. RESULTS: Among the 155 patients (age from 12 to 87 years old, with an average age of 57, 99 males and 56 females) with eye infections (160 eyes: 74 in the left eye, 76 in the right eye and 5 in both eyes, all of which were exogenous), 71 (45.81%) strains were gram-positive bacteria, 23 (14.84%) strains were gram-negative bacteria and 61 (39.35%) strains were fungi. Gram-positive bacteria were highly resistant to penicillin and erythromycin (78.87% and 46.48% respectively), but least resistant to vancomycin at 0. Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole (100% and 95.65% respectively), but least resistant to meropenem at 0. Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences (P

Copyright of Die Ophthalmologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The cornea, orbit, and other ocular tissues may get infected by fungi. Ophthalmic mycoses, often known as ocular fungal infections, are a significant cause of morbidity and blindness. For fungus infections, a brand-new azole derivative has been authorized. New immunological techniques would also be beneficial in the future for enhancing patient outcomes. Treatment of ocular illnesses presents a significant barrier in terms of getting medications into the eyes using traditional drug delivery methods, such as solutions. The main barriers are those between blood and the eyes, between lachrymal fluid and the eyes, and between medication losses from the ocular surface brought on by lachrymal fluid secretion. To increase the bioavailability and lengthen the residence duration of medications administered topically to the eye, a variety of ocular drug delivery carriers have been developed. The microemulsion is created using the PHASE TITRATION METHOD. Due to the dual hydrophilic and lipophilic properties of microemulsions, the loaded medications can diffuse passively and become significantly partitioned in the varying lipophilic-hydrophilic ocular barrier. This abstract will provide details on the microemulsions used to treat fungal infections of the eyes. [ABSTRACT FROM AUTHOR]

We report a case of a 53-year-old HIV-negative patient in San Francisco, California, USA, with no classic mpox prodromal symptoms or skin lesions who experienced fulminant, vision-threatening scleritis, keratitis, and uveitis. Deep sequence analysis identified monkeypox virus RNA in the aqueous humor. We confirmed the virus on the cornea and sclera by PCR.

ABSTRACTTank-binding kinase 1 (TBK1) plays a pivotal role as a cellular factor in regulating the immune response against herpes simplex virus type 1 (HSV-1). TBK1’s role in defending against HSV-1 is attributed to its capacity to induce the type I interferon response. Recent discoveries emphasize TBK1’s involvement in the regulation of optineurin (OPTN), an autophagy adaptor protein that plays a direct role in enhancing the antiviral response against HSV-1 through selective autophagy. Intriguingly, OPTN can also reciprocally regulate TBK1, leading to a limited understanding of the precise role of the OPTN-TBK1 axis in HSV-1 infection. In our study, we shed light on the relationship between OPTN and TBK1 in influencing the outcome of HSV-1 infection. Surprisingly, when TBK1 or OPTN was absent in cells, the spread and infectivity of HSV-1 did not align as expected. Furthermore, it was unexpected to note that cells lacking OPTN showed higher interferon expression compared to normal cells, yet they exhibited enhanced viral growth. Our investigations revealed that OPTN can directly degrade HSV-1 through autophagy even in the absence of active TBK1. Interestingly, we identified that another protein, Polo-like kinase 1 (PLK1), can compensate for the absence of TBK1 and trigger autophagy to restrict HSV-1. In summary, our findings highlight that OPTN significantly impacts the outcome of HSV-1 infection, regardless of the conventional antiviral response mediated by TBK1. Additionally, by introducing a new role for PLK1, this research provides valuable insights into the intricate interplay among OPTN, TBK1, and autophagy in shaping the course of HSV-1 infection.IMPORTANCEHerpes simplex virus type 1 (HSV-1) is globally prevalent, with latent infections observed in up to 80% of the population. The virus is known for subverting host defense mechanisms and infiltrating the nervous system to establish latency in peripheral ganglia. Multiple stressors can reactivate the virus, and recurrent herpes has been linked to vision loss and neurodegeneration. Identifying critical host factors that limit the spread of HSV-1 and the subsequent establishment of latent infection holds the potential to drive new intervention strategies for eradicating the virus. Numerous pieces of evidence underscore the significance of Tank-binding kinase 1 (TBK1) in restricting HSV-1. Reports have also suggested that phosphorylation of optineurin (OPTN) by TBK1 is required for triggering OPTN-mediated autophagy for HSV degradation. This report adds new insights into the roles of OPTN and TBK1 in HSV-1 infection and provides proof of a TBK1-independent HSV-1 restriction through OPTN. It confirms that TBK1 activation can be substituted by PLK1 to provide protection against HSV-1. In contrast, the activation of OPTN is likely an indispensable host defense mechanism for optimal defense against HSV-1.

Lagophthalmos express the imperfect palpebra closure. It can be result as feelings like there's commodity in the eyes, Ophthalmalgia, Epiphora or dry eyes, vague vision, red eyes, scleritis, light perceptivity, Insomnolence. Complete eyes close with a nictitation is important for maintaining a stable lacrimal layer and Healthy Eyes. Twenty years of girl visit to hospital with complaints of redness of left eye, Water secretion continuously specially with pain in left eye at night which was intolerable, severe light sensitivity, blurry vision, constant headache, not able to concentrate due to pain and blurry vision. Initially patient feels dry eyes during the day before a couple of day of starting continuously water secretion. On examination they conclude that patient eyes are not properly closed during sleeping which interpret in formation of stable tear film. After all examination they conclude that she has lagophthalmos. For management of her condition, she was prescribed with Optimoist Ultra 400 E/D, Moxiqua 0.5%. Lagophthalmos cannot be treated completely as the point so, Doctor suggests the lifelong therapy of this eye drops and eye gel for better outcomes and to prevent further symptoms flare. There should not be any surgical therapy in this case because lagophthalmos was detected in early stage within 2-3 weeks. According to guidelines if lagophthalmos is detected within 1-6 weeks then medical care therapy is sufficient to give better result. Lagophthalmos can be chronic if not treated early it can be causing complete and permeant vision loss. [ABSTRACT FROM AUTHOR]

To identify periodic trends in internet searches for ocular symptoms and to determine the seasonal peaks and troughs. This cross-sectional study examined publicly available Google Trends data from the United States (01/01/2015 to 12/31/2019). A list of common ocular symptoms was compiled from the American Academy of Ophthalmology Eye Health website and Wills Eye Manual. Ocular symptoms were stratified into categories involving vision change, eye pain, or eye redness. The search volume over time for each term was modeled using periodic regression functions and the goodness-of-fit was reported. Fisher's exact tests were used to compare the characteristics of periodic vs. non-periodic query terms. Seasonal trends were demonstrated by 45% (48/106) of the ocular symptoms included in this investigation. Search terms with best fit to the periodic model included stye (r2 = 0.89), pink eye (r2 = 0.82), dry eye (r2 = 0.76), blurry vision (r2 = 0.72), and swollen eye (r2 = 0.71). Periodic search terms were more likely to involve eye redness (21% vs. 11%, p =.014) and less likely to involve vision change (11% vs. 36%; p <.001). Periodic queries involving eye redness most often peaked in the spring and those involving eye pain peaked in the summer. Ocular symptom queries directly reflect seasonal trends for allergic eye disease and ocular trauma. Search query analyses can serve as accurate epidemiological tools with research and real-world clinical applications. [ABSTRACT FROM AUTHOR]

The present study applied a nano-synergistic approach to enhance besifloxacin's potency via nano-formulating besifloxacin on gold nanoparticles (Besi-AuNPs) and adding quercetin as a natural synergistic compound. In fact, a one-pot AuNP synthesis approach was applied for the generation of Besi-AuNPs, where besifloxacin itself acted as a reducing and capping agent. Characterization of Besi-AuNPs was performed by spectrophotometry, DLS, FTIR, and electron microscopy techniques. Moreover, antibacterial assessment of pure besifloxacin, Besi-AuNPs, and their combinations with quercetin were performed on Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. UV-spectra showed a peak of AuNPs at 526 nm, and the electron microscopy-based size was estimated to be 15 ± 3 nm. The effective MIC50 concentrations of besifloxacin after loading on AuNPs were reduced by approximately 50% against the tested bacterial strains. Interestingly, adding quercetin to Besi-AuNPs further enhanced their antibacterial potency, and isobologram analysis showed synergistic potential (combination index below 1) for different quercetin and Besi-AuNP combinations. However, Besi-AuNPs and quercetin combinations were most effective against Gram-positive S. aureus in comparison to Gram-negative P. aeruginosa and E. coli. Their potent activity against S. aureus has its own clinical significance, as it is one the main causative agents of ocular infection, and besifloxacin is primarily used for treating infectious eye diseases. Thus, the outcomes of the present study could be explored further to provide better medication for eye infections caused by resistant pathogens. [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) infection causes ocular and neurological pathologies with ZIKV-induction of developmental abnormalities following in utero infection a major concern. The study here has compared ZIKV and the related dengue virus (DENV) infection in the eye and brain. In vitro, both ZIKV and DENV could infect cell lines representing the retinal pigmented epithelium, endothelial cells, and Mueller cells, with distinct innate responses in each cell type. In a 1-day old mouse challenge model, both ZIKV and DENV infected the brain and eye by day 6 post-infection (pi). ZIKV was present at comparable levels in both tissues, with RNA increasing with time post-infection. DENV infected the brain, but RNA was detected in the eye of less than half of the mice challenged. NanoString analysis demonstrated comparable host responses in the brain for both viruses, including induction of mRNA for myosin light chain-2 (Mly2), and numerous antiviral and inflammatory genes. Notably, mRNA for multiple complement proteins were induced, but C2 and C4a were uniquely induced by ZIKV but not DENV. Consistent with the viral infection in the eye, DENV induced few responses while ZIKV induced substantial inflammatory and antiviral responses. Compared to the brain, ZIKV in the eye did not induce mRNAs such as C3, downregulated Retnla, and upregulated CSF-1. Morphologically, the ZIKV-infected retina demonstrated reduced formation of specific retinal layers. Thus, although ZIKV and DENV can both infect the eye and brain, there are distinct differences in host cell and tissue inflammatory responses that may be relevant to ZIKV replication and disease. [ABSTRACT FROM AUTHOR]

Background: Alternaria spp are ubiquitous pigmented filamentous fungi that can cause opportunistic human infections. These molds can be found in healthy individuals and the most frequently observed clinical manifestations are skin infections, ocular mycosis, rhinosinusitis, among others. Immunosuppression (both local and systemic) as well as contact or trauma with contaminated matter are important risk and predisposing factors for ocular mycosis. Accurate diagnosis with microscopy and culture is crucial since infections by filamentous fungi are sight-threatening, and clinically indistinguishable from bacterial disease. In general terms, conventional antifungal drugs are effective. Case Presentation: We report a case of Alternaria alternata keratitis after ocular trauma with biological material in a 44-year-old man's functional single eye, which had a good clinical and functional evolution after topical therapy with voriconazole. Conclusion: This case accounts the importance of thinking about other etiological diagnoses in infectious keratitis refractory to the established therapy and with a history of trauma with biological material. [ABSTRACT FROM AUTHOR]

We studied the antimicrobial effect of gold quantum dots (AuQDs), femtosecond laser irradiation, and the combined effect of laser irradiation and AuQD treatment against common infectious eye pathogens. The INSPIRE HF100 laser system (Spectra Physics) provided a femtosecond laser, which was pumped by a mode-locked femtosecond Ti: sapphire laser MAI TAI HP (Spectra Physics), while a Quanta-Ray nanosecond Nd: YAG laser (Spectra-Physics) was used to precisely synthesize 7.8, 8.7, and 11.6 nm spherical AuQDs. Then, the in vitro growth kinetics and growth rate analysis of E. coli, methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, and Candida albicans (treated with the AuQDs, femtosecond laser irradiation, or combined laser and AuQDs treatment) was measured. The biocompatibility of the AuQDs with the retinal epithelial cell lines (ARPE-19) and their toxicity to the cells was assayed. The results showed that (1) in vitro irradiation using a 159 J/cm2 energy density obtained from the 400 nm femtosecond laser suppressed the growth of each of the five pathogens. (2) Similarly, treatment with the AuQDs was antimicrobial against the four bacteria. The AuQDs with an average size of 7.8 nm were more highly antimicrobial and biocompatible and were less cytotoxic than the larger AuQD sizes. (3) The combined femtosecond laser irradiation and AuQD treatment was more highly antimicrobial than each treatment alone. (4) The AuQD treatment did not impair the rate of wound closure in vitro. These findings suggest that combined femtosecond laser irradiation and AuQD treatment is significantly antimicrobial against Candida albicans, Gram-positive L. monocytogenes, S. aureus, and E. faecalis, as well as Gram-negative E. coli. The nontoxicity and biocompatibility of the AuQD particles tested suggest that this form of treatment may be clinically viable. [ABSTRACT FROM AUTHOR]

The present study applied a nano-synergistic approach to enhance besifloxacin’s potency via nano-formulating besifloxacin on gold nanoparticles (Besi-AuNPs) and adding quercetin as a natural synergistic compound. In fact, a one-pot AuNP synthesis approach was applied for the generation of Besi-AuNPs, where besifloxacin itself acted as a reducing and capping agent. Characterization of Besi-AuNPs was performed by spectrophotometry, DLS, FTIR, and electron microscopy techniques. Moreover, antibacterial assessment of pure besifloxacin, Besi-AuNPs, and their combinations with quercetin were performed on Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. UV-spectra showed a peak of AuNPs at 526 nm, and the electron microscopy-based size was estimated to be 15 ± 3 nm. The effective MIC50 concentrations of besifloxacin after loading on AuNPs were reduced by approximately 50% against the tested bacterial strains. Interestingly, adding quercetin to Besi-AuNPs further enhanced their antibacterial potency, and isobologram analysis showed synergistic potential (combination index below 1) for different quercetin and Besi-AuNP combinations. However, Besi-AuNPs and quercetin combinations were most effective against Gram-positive S. aureus in comparison to Gram-negative P. aeruginosa and E. coli. Their potent activity against S. aureus has its own clinical significance, as it is one the main causative agents of ocular infection, and besifloxacin is primarily used for treating infectious eye diseases. Thus, the outcomes of the present study could be explored further to provide better medication for eye infections caused by resistant pathogens.

While primarily Gram-positive bacteria cause bacterial eye infections, several Gram-negative species also pose eye health risks. Currently, few studies have tried to understand the pathogenic mechanisms involved in E. coli eye infections. Therefore, this study aimed to establish the pathogenic potential of E. coli strains isolated from eye infections. Twenty-two strains isolated between 2005 and 2019 from patients with keratitis or conjunctivitis were included and submitted to traditional polymerase chain reactions (PCR) to define their virulence profile, phylogeny, clonal relationship, and sequence type (ST). Phenotypic assays were employed to determine hemolytic activity, antimicrobial susceptibility, and adhesion to human primary corneal epithelial cells (PCS-700-010). The phylogenetic results indicated that groups B2 and ST131 were the most frequent. Twenty-five virulence genes were found among our strains, with ecp, sitA, fimA, and fyuA being the most prevalent. Two strains presented a hemolytic phenotype, and resistance to ciprofloxacin and ertapenem was found in six strains and one strain, respectively. Regarding adherence, all but one strains adhered in vitro to corneal cells. Our results indicate significant genetic and virulence variation among ocular strains and point to an ocular pathogenic potential related to multiple virulence mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Steroids for Corneal Ulcers Trial (SCUT) was a multicenter, international study of bacterial keratitis in which 101 Pseudomonas aeruginosa infections were treated. Twenty-two of 101 P. aeruginosa isolates collected had a colony morphology characteristic of a loss-of-function mutation in lasR, the gene encoding a quorum-sensing master regulator. Ulcers caused by these 22 strains were associated with larger areas of corneal opacification, worse vision, and a lower rate of vision recovery in response to treatment than ulcers caused by the other isolates. The lasR sequences from these isolates each contained one of three nonsynonymous substitutions, and these strains were deficient in production of LasR-regulated protease and rhamnolipids. Replacement of lasR with either of the two most common lasR alleles from the SCUT isolates was sufficient to decrease protease and rhamnolipid production in PA14. Loss of LasR function is associated with increased production of CupA fimbriae, and the LasR-defective isolates exhibited higher production of CupA fimbriae than LasR-intact isolates. Strains with the same lasR mutation were of the same multilocus sequence type, suggesting that LasR-deficient, environmental P. aeruginosa strains were endemic to the area, and infections caused by these strains were associated with worse patient outcomes in the SCUT study. (This study has been registered at ClinicalTrials.gov under registration no. NCT00324168.) IMPORTANCE The LasR transcription factor is an important regulator of quorum sensing in P. aeruginosa and positively controls multiple virulence-associated pathways. The emergence of strains with lasR loss-of-function alleles in chronic disease is well described and is thought to represent a specific adaptation to the host environment. However, the prevalence and virulence of these strains in acute infections remain unclear. This report describes observations revealing that lasR mutants were common among isolates from a large, multicenter clinical study of keratitis and were associated with worse clinical outcomes than LasR-intact strains despite reduced production of LasR-regulated factors. Additionally, these lasR mutants were closely related strains or clones, as determined by molecular analysis. Because bacterial keratitis is community acquired, these data indicate infection by endemic, LasR-deficient strains in the environment. These results suggest that the conventional paradigm regarding the role for LasR-mediated regulation of virulence is more complex than previously appreciated.

Abstract A lot of dentists and dental personnel are at high risk of contracting eye infections during operative procedures involving aerosols. As many may not be aware of it, they often ignore the precautions to be taken for prevention of such infections. This is one such case report of a dental intern where an eyelid infection arose shortly after she treated a patient with an infected tooth in an operative procedure. This case report emphasizes the importance of preventive barriers for the dentist, and that how special protective gear is required for doing restorative cases which involve dealing with infection.

Background: The most common ocular disease affecting cattle worldwide is infectious bovine keratoconjunctivitis (IBK), which has been associated with Moraxella bovis bacterium. Objective: To report the molecular characterization of the ocular bacterial microbiota and its relation to IBK in cattle in two dairy regions in Michoacán, Mexico. Methods: A total population of 761 bovines were evaluated, of which 17 (2.23%) showed symptoms of IBK. Thirty-eight bacterial isolates from ocular samples of bovines with IBK were characterized by Gram-staining and antimicrobial sensitivity. In addition, isolates were identified by sequence comparisons of the 16S ribosomal gene. Results: The genus Moraxella was one of the most abundant bacteria and M. bovoculi was the most predominant species. Conclusion: The bacterial isolates identified in eye lesions of cattle and associated to IBK are diverse. To the author´s knowledge, this is the first study on the subject in Mexico; therefore, more research is needed to estimate the incidence of IBK and determine its associated microbiota.

Eye infection is one of the temporary invalidity causes that can lead to blindness. The former antibacterial components of eye drops were polyhexamethylene guanidine hydrochloride and polyhexamethylene guanidine phosphate. Polyhexamethylene guanidine in the form of form of succinate with preserved activity and lover toxicity is described. The antibacterial activity spectra of polyhexamethylene guanidine succinate and polyhexamethylene guanidine hydrochloride were comparatively estimated.

The development of potent antibiotic alternatives with rapid bactericidal properties is of great importance in addressing the current antibiotic crisis. One representative example is the topical delivery of predatory bacteria to treat ocular bacterial infections. However, there is a lack of suitable methods for the delivery of predatory bacteria into ocular tissue. This work introduces cryomicroneedles (cryoMN) for the ocular delivery of predatory Bdellovibrio bacteriovorus (B. bacteriovorus) bacteria. The cryoMN patches are prepared by freezing B. bacteriovorus containing a cryoprotectant medium in a microneedle template. The viability of B. bacteriovorus in cryoMNs remains above 80% as found in long‐term storage studies, and they successfully impede the growth of gram‐negative bacteria in vitro or in a rodent eye infection model. The infection is significantly relieved by nearly six times through 2.5 days of treatment without substantial effects on the cornea thickness and morphology. This approach represents the safe and efficient delivery of new class of antimicrobial armamentarium to otherwise impermeable ocular surface and opens up new avenues for the treatment of ocular surface disorders. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The development of potent antibiotic alternatives with rapid bactericidal properties is of great importance in addressing the current antibiotic crisis. One representative example is the topical delivery of predatory bacteria to treat ocular bacterial infections. However, there is a lack of suitable methods for the delivery of predatory bacteria into ocular tissue. This work introduces cryomicroneedles (cryoMN) for the ocular delivery of predatory Bdellovibrio bacteriovorus (B. bacteriovorus) bacteria. The cryoMN patches are prepared by freezing B. bacteriovorus containing a cryoprotectant medium in a microneedle template. The viability of B. bacteriovorus in cryoMNs remains above 80% as found in long‐term storage studies, and they successfully impede the growth of gram‐negative bacteria in vitro or in a rodent eye infection model. The infection is significantly relieved by nearly six times through 2.5 days of treatment without substantial effects on the cornea thickness and morphology. This approach represents the safe and efficient delivery of new class of antimicrobial armamentarium to otherwise impermeable ocular surface and opens up new avenues for the treatment of ocular surface disorders.

We studied the antimicrobial effect of gold quantum dots (AuQDs), femtosecond laser irradiation, and the combined effect of laser irradiation and AuQD treatment against common infectious eye pathogens. The INSPIRE HF100 laser system (Spectra Physics) provided a femtosecond laser, which was pumped by a mode-locked femtosecond Ti: sapphire laser MAI TAI HP (Spectra Physics), while a Quanta-Ray nanosecond Nd: YAG laser (Spectra-Physics) was used to precisely synthesize 7.8, 8.7, and 11.6 nm spherical AuQDs. Then, the in vitro growth kinetics and growth rate analysis of E. coli, methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, and Candida albicans (treated with the AuQDs, femtosecond laser irradiation, or combined laser and AuQDs treatment) was measured. The biocompatibility of the AuQDs with the retinal epithelial cell lines (ARPE-19) and their toxicity to the cells was assayed. The results showed that (1) in vitro irradiation using a 159 J/cm2 energy density obtained from the 400 nm femtosecond laser suppressed the growth of each of the five pathogens. (2) Similarly, treatment with the AuQDs was antimicrobial against the four bacteria. The AuQDs with an average size of 7.8 nm were more highly antimicrobial and biocompatible and were less cytotoxic than the larger AuQD sizes. (3) The combined femtosecond laser irradiation and AuQD treatment was more highly antimicrobial than each treatment alone. (4) The AuQD treatment did not impair the rate of wound closure in vitro. These findings suggest that combined femtosecond laser irradiation and AuQD treatment is significantly antimicrobial against Candida albicans, Gram-positive L. monocytogenes, S. aureus, and E. faecalis, as well as Gram-negative E. coli. The nontoxicity and biocompatibility of the AuQD particles tested suggest that this form of treatment may be clinically viable.

Fungal eye infections can lead to loss of vision and blindness. The disease is most prevalent in the tropics, although case numbers in moderate climates are increasing as well. This study aimed to determine the dominating filamentous fungi causing eye infections in Germany and their antifungal susceptibility profiles in order to improve treatment, including cases with unidentified pathogenic fungi. As such, we studied all filamentous fungi isolated from the eye or associated materials that were sent to the NRZMyk between 2014 and 2020. All strains were molecularly identified and antifungal susceptibility testing according to the EUCAST protocol was performed for common species. In total, 242 strains of 66 species were received. Fusarium was the dominating genus, followed by Aspergillus, Purpureocillium, Alternaria, and Scedosporium. The most prevalent species in eye samples were Fusarium petroliphilum, F. keratoplasticum, and F. solani of the Fusarium solani species complex. The spectrum of species comprises less susceptible taxa for amphotericin B, natamycin, and azoles, including voriconazole. Natamycin is effective for most species but not for Aspergillus flavus or Purpureocillium spp. Some strains of F. solani show MICs higher than 16 mg/L. Our data underline the importance of species identification for correct treatment. [ABSTRACT FROM AUTHOR]

AIM:To study the distribution, drug resistance and epidemic characteristics of pathogenic bacteria in neonatal eye infection in Cangnan County, Zhejiang Province from 2014 to 2018, and to provide the basis for the prevention, diagnosis and treatment of clinical conditions.METHODS: Totally 108 strains of pathogenic bacteria isolated from 294 eyes specimens from neonatal clinic from January 2014 to December 2018 were identified, common drug sensitivity test and epidemiological characteristics were summarized and analyzed.RESULTS: The detection rate of pathogenic bacteria in 294 ocular secretions was 36.7%(108/294). The main flora included 48 strains of Staphylococcus epidermidis(44.4%), 16 strains of Staphylococcus aureus(14.8%), 24 cases of Escherichia coli(22.2%), 12 strains of Neisseria gonorrhoeae(11.1%), 5 strains of Corynebacterium diphtheria(4.6%), 2 strains of Enterococcus(1.9%)and 1 case of Streptococcus (0.9%). The main pathogens are highly sensitive to amikacin and netilmicin, and are highly sensitive to jellithromycin and netilmicin. The activity of gentamicin is poor. It has good activity against quinolones.CONCLUSION:Staphylococcus is the main pathogen of neonatal eye infection, and eye antibiotics commonly used in clinic have good antibacterial activity against all kinds of pathogenic bacteria.

Aims: The contact lens (CL) has become one of the most convenience refractive devices used in vision correction, occupational and in cosmetics purposes. Despite the convenience of CL usage, poor hygiene might cause eye infections due to microbial contamination. In this work, a random collection of used CL cases among Universiti Malaysia Terengganu (UMT) students had shown the emergence of antibiotic-resistant bacteria towards commonly used antibiotics to treat eye infections. Aims: The contact lens (CL) has become one of the most convenience refractive devices used in vision correction, occupational and in cosmetics purposes. Despite the convenience of CL usage, poor hygiene might cause eye infections due to microbial contamination. In this work, a random collection of used CL cases among Universiti Malaysia Terengganu (UMT) students had shown the emergence of antibiotic-resistant bacteria towards commonly used antibiotics to treat eye infections. Conclusion, significance and impact of study: This study highlights the emergence of antibiotic-resistant bacteria that can cause severe eye infections among CL wearer. The high percentage of contamination (>50%) found from the isolates reflected on the lack of hygiene practice on the CL handling. Thus, it is crucial to perceive this study as microbial contamination will lead to more serious eye infection disease such as conjunctivitis and keratitis. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a most important reason of bacterial keratitis. The emergence of S. aureus resistance to methicillin necessitates searching for new antimicrobial components for keratitis. CM11 is a cationic peptide with strong antibacterial activity against a range of bacteria. In this study, in vitro bactericidal activity of CM11 was investigated using the time-killing assay. For this purpose, corneal methicillin-resistant S. aureus (MRSA)-infected rabbit models were experimentally developed through intrastromal injection of bacteria. The infected rabbits were treated in three groups by artificial tear, gentamicin, and CM11, and their conjunctiva, iris, and cornea were clinically examined using a slit lamp and histopathological examination. The variance analyses of microbial (colony counts) and pathological examinations on the harvested cornea samples showed a significant improvement in the treated groups (CM11 and gentamicin) compared to the control eyes (P ≤ 0.05). According to findings, CM11 and gentamicin could significantly reduce the CFU in comparison with the group received artificial tear. The mean bacterial counts (log CFU/ml) from corneal culture were 2.1, 5.02, and 8.89 for gentamicin, CM11, and control group, respectively (P ≤ 0.05). The above-mentioned findings displayed the efficacy of CM11 cationic peptide for curing the MRSA-mediated keratitis. [ABSTRACT FROM AUTHOR]

Background Microbial keratitis is a leading cause of preventable blindness worldwide. Conventional sampling and culture techniques are time-consuming, with over 40% of cases being culture-negative. Nanopore sequencing technology is portable and capable of generating long sequencing reads in real-time. The aim of this study is to evaluate the potential of nanopore sequencing directly from clinical samples for the diagnosis of bacterial microbial keratitis. Methods Using full-length 16S rRNA amplicon sequences from a defined mock microbial community, we evaluated and benchmarked our bioinformatics analysis pipeline for taxonomic assignment on three different 16S rRNA databases (NCBI 16S RefSeq, RDP and SILVA) with clustering at 97%, 99% and 100% similarities. Next, we optimised the sample collection using an ex vivo porcine model of microbial keratitis to compare DNA recovery rates of 12 different collection methods: 21-gauge needle, PTFE membrane (4 mm and 6 mm), Isohelix™ SK-2S, Sugi® Eyespear, Cotton, Rayon, Dryswab™, Hydraflock®, Albumin-coated, Purflock®, Purfoam and Polyester swabs. As a proof-of-concept study, we then used the sampling technique that provided the highest DNA recovery, along with the optimised bioinformatics pipeline, to prospectively collected samples from patients with suspected microbial keratitis. The resulting nanopore sequencing results were then compared to standard microbiology culture methods. Results We found that applying alignment filtering to nanopore sequencing reads and aligning to the NCBI 16S RefSeq database at 100% similarity provided the most accurate bacterial taxa assignment. DNA concentration recovery rates differed significantly between the collection methods (p < 0.001), with the Sugi® Eyespear swab providing the highest mean rank of DNA concentration. Then, applying the optimised collection method and bioinformatics pipeline directly to samples from two patients with suspected microbial keratitis, sequencing results from Patient A were in agreement with culture results, whilst Patient B, with negative culture results and previous antibiotic use, showed agreement between nanopore and Illumina Miseq sequencing results. Conclusion We have optimised collection methods and demonstrated a novel workflow for identification of bacterial microbial keratitis using full-length 16S nanopore sequencing.

While primarily Gram-positive bacteria cause bacterial eye infections, several Gram-negative species also pose eye health risks. Currently, few studies have tried to understand the pathogenic mechanisms involved in E. coli eye infections. Therefore, this study aimed to establish the pathogenic potential of E. coli strains isolated from eye infections. Twenty-two strains isolated between 2005 and 2019 from patients with keratitis or conjunctivitis were included and submitted to traditional polymerase chain reactions (PCR) to define their virulence profile, phylogeny, clonal relationship, and sequence type (ST). Phenotypic assays were employed to determine hemolytic activity, antimicrobial susceptibility, and adhesion to human primary corneal epithelial cells (PCS-700-010). The phylogenetic results indicated that groups B2 and ST131 were the most frequent. Twenty-five virulence genes were found among our strains, with ecp, sitA, fimA, and fyuA being the most prevalent. Two strains presented a hemolytic phenotype, and resistance to ciprofloxacin and ertapenem was found in six strains and one strain, respectively. Regarding adherence, all but one strains adhered in vitro to corneal cells. Our results indicate significant genetic and virulence variation among ocular strains and point to an ocular pathogenic potential related to multiple virulence mechanisms.

The most common ocular disease affecting cattle worldwide is infectious bovine keratoconjunctivitis (IBK), which has been associated with Moraxella bovis bacterium. Objective: To report the molecular characterization of the ocular bacterial microbiota and its relation to IBK in cattle in two dairy regions in Michoacán, Mexico. Methods: A total population of 761 bovines were evaluated, of which 17 (2.23%) showed symptoms of IBK. Thirty-eight bacterial isolates from ocular samples of bovines with IBK were characterized by Gram-staining and antimicrobial sensitivity. In addition, isolates were identified by sequence comparisons of the 16S ribosomal gene. Results: The genus Moraxella was one of the most abundant bacteria and M. bovoculi was the most predominant species. Conclusion: The bacterial isolates identified in eye lesions of cattle and associated to IBK are diverse. To the author's knowledge, this is the first study on the subject in Mexico; therefore, more research is needed to estimate the incidence of IBK and determine its associated microbiota. [ABSTRACT FROM AUTHOR]

Aim: To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs., Methods: The clinical data of 155 patients were retrospectively collected in this study, and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed., Results: Among the 155 patients (age from 12 to 87 years old, with an average age of 57, 99 males and 56 females) with eye infections (160 eyes: 74 in the left eye, 76 in the right eye and 5 in both eyes, all of which were exogenous), 71 (45.81%) strains were gram-positive bacteria, 23 (14.84%) strains were gram-negative bacteria and 61 (39.35%) strains were fungi. Gram-positive bacteria were highly resistant to penicillin and erythromycin (78.87% and 46.48% respectively), but least resistant to vancomycin at 0. Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole (100% and 95.65% respectively), but least resistant to meropenem at 0. Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences ( P <0.05) in the resistance of both to cefoxitin, cotrimoxazole, levofloxacin, cefuroxime, ceftriaxone and ceftazidime, and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria. The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva, cornea, aqueous humor or vitreous body and other eye parts. Besides, Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections., Conclusion: Gram-positive bacteria are the dominant bacteria in eye infections, followed by gram-negative bacteria and fungi. Considering the resistance of gram-negative bacteria to multiple drugs, monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections., Competing Interests: Conflicts of Interest: Zhang L, None; You HZ, None; Wang GH, None; Xu W, None; Li JS, None; Zhao QL, None; Du S, None., (International Journal of Ophthalmology Press.)

Endogenous endophthalmitis represents an ophthalmological emergency requiring immediate diagnostics and treatment. Pathogens should be detected using appropriate methods, such as the Freiburg endophthalmitis set. In bacterial endophthalmitis both Gram-positive and Gram-negative bacteria can be detected. Frequent underlying sources include endocarditis, gastrointestinal or urogenital surgery, indwelling venous catheters, liver abscesses, skin or soft tissue infections, meningitis or less commonly, intravenous drug abuse. The treatment consists of systemic and intraocular administration of antibiotics and vitrectomy. Systemic or intraocular corticosteroids can additionally be considered., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Eye infection due to microbial infection is hard to treat and painful. Two types of eye drops that are commonly used to relieve eye pain offered by pharmacists have been tested in this study namely solution A (containing tetrahydrozoline hydrochloride) and solution B (containing gentamicin and dexamethasone). The efficacy and the activities of these eye drops were tested on Acanthamoeba sp. (a clinical isolate from an Acanthamoeba keratitis patient) to study the cytotoxicity effects of the solutions on the Acanthamoeba. The Acanthamoeba were exposed to solution A and B for 24 hr and cell viability was assessed using MTT assays, morphological changes using the light microscope and through acridine orange and propidium iodide (AO/PI) staining for cytoplasmic biochemical activities. The IC50 value for Acanthamoeba cell viability was 45.1% and 20.3% for solutions A and B respectively. Morphological observation shows the inhibition of acanthapodia formation on the surface of the cells. Solution A and B-treated Acanthamoeba appeared in the red color of the cytoplasm upon staining with AO/PI indicating a necrotic mode of cell death. This is due to loss of membrane integrity of Acanthamoeba cell membrane after exposed to solution A and B at their IC50 value. It is shown that solutions A and B can cause cell death in trophozoite of Acanthamoeba cells at moderate IC50 value. Unfortunately, the necrosis mode of cell death is not a preferable type of cell death for treating Acanthamoeba infection. Therefore, it can be concluded that solutions A and B are not suitable to treat eye infected with Acanthamoeba sp. as it does not promise absolute healing as the solution concentration needed is quite high and the cell death mechanism is necrosis. [ABSTRACT FROM AUTHOR]

The aim of the present study is to check the relationship between virus detection on the conjunctival swabs by RT-PCR and the systemic and ocular clinical data, treatments, and to the modalities of administration of supplemental oxygen. The SARS-CoV-2 RNA reverse-transcriptase PCR assay of conjunctival brushing samples and the corneal/conjunctival clinical findings were evaluated in 18 eyes of 9 consecutive patients admitted to the COVID-19 Sub-intensive Unit of Salerno Hospital University, Italy. Conjunctival swabs were positive for SARS-CoV-2 in 13 eyes of 7 patients; corneal epithelial defects were detected in 9 eyes. The seven patients with ocular involvement from SARS-CoV-2 had undergone treatment with a full-face mask or oxygen helmet in the last week, while the two subjects with negative conjunctival swabs had been treated with high flow nasal cannula. The positivity to the conjunctival test for SARS-CoV-2 was higher (72%) than that reported in the literature (10–15%) and related in all cases to the use of facial respiratory devices. These results suggest that exposure of unprotected eyes to aerosols containing high concentrations of SARS-CoV-2 could cause a keratoconjunctival viral infection. Further studies are needed to verify the causal link with the use of respiratory facial devices in patients suffering from COVID-19 pneumonia.

It is known that not all red eyes are caused by infections. Furthermore, not all eye infections will react to antibiotic eye drops. Most cases of conjunctivitis are due to viral causes, do not require antibiotic eye drops and are usually self-limiting. Serious ophthalmic conditions such as infectious keratitis can lead to blindness; it is an emergency that requires specialist treatment. Also infectious endophthalmitis has become more frequent with the use of intravitreal injections. Intravitreal antibiotics are needed to try and prevent visual loss. To ensure therapeutic local exposure ophthalmic antibiotic solutions should be applied frequently into the eye.

Abstract Background Helcococcus ovis, belonging to the genus of Helcococcu in Peptostreptococcaceae, is one kind of facultative anaerobic and gram-positive cocci, which was first isolated from a mixed infection in sheep in 1999. To our knowledge, it’s known as an invasive pathogen in animals, and never been reported as a human pathogen in published literature. The aims of this work are to describe the first report of H. ovis which was recovered from the artificial eye of human case and perform a literature review. Case presentation A 26 year-old man reporting pyogenic infection with an artificial eye attended ophthalmic ward in Tongji hospital. After physical examination, clinical and laboratory investigations, the diagnosis of eye infection caused by Helcococcus ovis and Staphylococcus aureus was established. Receiving a medico-surgical approach, the patient was successfully treated. The treatment consisted in intravenous cefotaxime and ornidazole, levofloxacin eye drops during two weeks and removing of right artificial eye with debridement. Conclusions We describe here the first known case of H. ovis which was recovered from human artificial eye. This report different from previous data found in the literature emphasizes the invasive potential of this bacterial species as a pathogen in human. Prospectively, the application of next generation sequencing tools would contribute to a more accurate classification of clinical strains.

Abstract Background Colonisation with Panton-Valentine Leukocidin expressing strains of Staphylococcus aureus (PVL + SA) is characterised by recurrent skin and soft tissue infections. While periorbital and orbital infections are common in children and frequently caused by S. aureus the role of PVL + SA in recurrent eye infections has not been studied. This study aimed to detect and report frequency and recurrence of periorbital or orbital infections as additional symptoms of PVL + SA colonisation in children. Methods We conducted a retrospective cohort study of pediatric patients who were treated for PVL + SA skin and soft tissue infection in our in- and outpatient clinics in Berlin, Germany from January 2012 to January 2017. We identified cases with periorbital or orbital infections in the year prior to the first PVL + SA evidence. In these cases, we conducted follow-up interviews by phone to determine recurrence of symptoms after the completion of decolonisation procedures. Results Fifty pediatric patients (age range: one week to 17 years) were evaluated and treated for PVL + SA infections in the reported time period. 19 patients (38%) reported periorbital infection or conjunctivitis, with recurrent hordeola as the most frequent finding (n = 9; 18%). Reappearance of hordeola (n = 5) was associated with recurrence of skin and soft tissue infections and/or de novo detection of PVL + SA. No further hordeola or other eye infections occurred after successful decolonisation. Conclusion Our findings suggest a frequent involvement of periorbital skin in children with PVL + SA infections. Pediatric patients with recurrent periorbital infections might benefit from PVL + SA screening and consecutive decolonisation procedures.

The present study included 250 clinical samples during the period between December 2018 -- April 2019 on 250 patients with ophthalmological infections of both sexes & different ages (3 days -75 years old), attend to ophthalmological clinic in hospital Ibn-AL-Hythem for eyes infection in Baghdad. The ophthalmological infections classified into 3 types according to the anatomical site of involvement. The first group was conjunctivitis (200) case, the 2nd was Blepharitis (35) case & the 3rd was Keratitis (15) cases. Isolation of the causative micro-organisms for the previous infections, culture & sensitivity test to different antimicrobial agents were done. The results showed that 200 (229.4)% are you giren significant growth of bacteria while 50 (69.07%) were no growth for bacteria. Include Staphylococcus aureus (77.6%), Staphylococcus epidermidis (13.6%), Streptococcus pneumonia (6.4%) & Streptococcus pyogenes (2.1%), while G-ve isolates 61 (30.5%) include (7) species of bacteria; Haemophilus influenza (81.9%), Klebsiella pneumonia (6.5%), Proteus spp & Pseudomonas aeruginosa, the Same (3.2%) for each & finally Neisseria gonorrhoeae, Moraxella spp, Acinetobacter were the least (1.6%) for each. Antimicrobial (12 agents) susceptibility of the bacterial isolates revealed marked resistant of these isolates for most antimicrobial agents e.g. Penicillin (87.8%), amoxicillin/clavulanicacid (84.4%), cephalexien (83.9%), erythromycin (83.4%), ampicillin (71.3%) while the least resistant (8.2%) reported for ciprofloxacin. [ABSTRACT FROM AUTHOR]

The aim of the study was investigate the DNA polymorphisms of Aspergillus flavus and Aspergillus tamarii isolated from regional fungal keratitis cases based on random amplified polymorphic DNA (RAPD) analyses. Thirty-two A. flavus and six A. tamarii isolates were identified using conventional macroscopic and microscopic features. Five decamer primers were used to amplify the genomic DNA sequences of the test isolates, and 140 total RAPD patterns were generated among them. From each of the 38 isolates, a range of 15–30 RAPD types were revealed. All of these were isolated from male farmers from Tamil Nadu. In the future, RAPD analyses could be employed as a reliable and rapid technique to differentiate among keratitis isolates of fungal pathogens. [ABSTRACT FROM AUTHOR]

Introduction: Eye diseases originated due to virus occupy an important place in daily routine of the specialty. Objective: To characterize patients with eye infections due to herpesvirus according to clinical and epidemiological variables of interest. Methods: A descriptive and cross-sectional study of 29 adult patients with infections due to herpesvirus was carried out, they were assisted in the ophthalmologic service of Dr. Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba, from September, 2012 to the same month in 2013. Results: In the case material white skin patients (55.1 %), female sex (69.0 %) and 57 years and over age group (48.3 %) prevailed. Red eye and ciliumconjuntival injection constituted the most common symptoms and signs (75.9 %). The most frequent lesions were located in the eyelids, the skin and cornea (31.0 %). The affectation of the visual acuteness below 0.3 was related to the occurrence of stromal affectation and the localization of lesions in the pupilar area. No patient presented inflammation of the later segment. Conclusions: Arguments about the existent relationship between the localization of lesions and the affectation of the visual acuteness were not found, which prevented to carry out comparisons. [ABSTRACT FROM AUTHOR]