Correction to: The Activity of Polyhomoarginine against Acanthamoeba castellanii (Biology, (2022), 11, 12, (1726), 10.3390/biology11121726)

In the original publication [1], there was a mistake in the legend for ** Figure 1—4 **. **Using a two-sample t-test and two-tailed distribution**. The correct legend appears below. **i. Figure 1: Change “(** p < 0.001 using a two-sample t-test and two-tailed distribution).” to “(** p < 0.001 using one way ANOVA).” ii. Figure 2: Change “(** p < 0.001, * p < 0.05 using a two-sample t-test and two-tailed distribution).” to “(** p < 0.001, * p < 0.05 using one way ANOVA).” iii. Figure 3: change “(** p < 0.001, * p < 0.05 using a two-sample t-test and two-tailed distribution).” to “(** p < 0.001, * p < 0.05 using one way ANOVA).” iv. Figure 4: change “(** p < 0.001, * p < 0.05 using a two-sample t-test and two-tailed distribution).” to “(** p < 0.001, * p < 0.05 using one way ANOVA).” ** There was an error in the original publication. **Full name of PHMB missing in Introduction**. A correction has been made to **Introduction**, **Paragraph Number—3**: i. Change “PHMB or chlorhexidine are widely used to treat this infection as monotherapies or in combination” to “Polyhexamethylene biguanide or chlorhexidine are widely used to treat this infection as monotherapies or in combination”. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated

Antibiotic Resistance Characteristics of Pseudomonas aeruginosa Isolated from Keratitis in Australia and India.

This study investigated genomic differences in Australian and Indian Pseudomonas aeruginosa isolates from keratitis (infection of the cornea). Overall, the Indian isolates were resistant to more antibiotics, with some of those isolates being multi-drug resistant. Acquired genes were related to resistance to fluoroquinolones, aminoglycosides, beta-lactams, macrolides, sulphonamides, and tetracycline and were more frequent in Indian (96%) than in Australian (35%) isolates (p = 0.02). Indian isolates had large numbers of gene variations (median 50,006, IQR = 26,967-50,600) compared to Australian isolates (median 26,317, IQR = 25,681-33,780). There were a larger number of mutations in the mutL and uvrD genes associated with the mismatch repair (MMR) system in Indian isolates, which may result in strains losing their efficacy for DNA repair. The number of gene variations were greater in isolates carrying MMR system genes or exoU. In the phylogenetic division, the number of core genes were similar in both groups, but Indian isolates had larger numbers of pan genes (median 6518, IQR = 6040-6935). Clones related to three different sequence types-ST308, ST316, and ST491-were found among Indian isolates. Only one clone, ST233, containing two strains was present in Australian isolates. The most striking differences between Australian and Indian isolates were carriage of exoU (that encodes a cytolytic phospholipase) in Indian isolates and exoS (that encodes for GTPase activator activity) in Australian isolates, large number of acquired resistance genes, greater changes to MMR genes, and a larger pan genome as well as increased overall genetic variation in the Indian isolates

Immobilization of antibacterial dihydropyrrol-2-ones on functional polymer supports to prevent bacterial infections in vivo

Antibiotic-resistant Staphylococcus aureus is of great concern, as it causes a wide range of life-threatening infections. The current study demonstrates that dihydropyrrolone (DHP)-coated polyacrylamide substrates are effective in reducing the number of culturable clinical isolates of S. aureus in vitro in a dose-dependent manner and are able to reduce the pathogenic potential of staphylococcal infection in a subcutaneous infection model. Covalently bound DHPs therefore show great potential for use as an antimicrobial strategy in device-related applications. Copyright © 2012, American Society for Microbiology. All Rights Reserved

Feasibility of Silicon Quantum Dots as a Biomarker for the Bioimaging of Tear Film

This study investigated the fluorescence and biocompatibility of hydrophilic silicon quantum dots (SiQDs) that are doped with scandium (Sc-SiQDs), copper (Cu-SiQDs), and zinc (Zn-SiQDs), indicating their feasibility for the bioimaging of tear film. SiQDs were investigated for fluorescence emission by the in vitro imaging of artificial tears (TheraTears®), using an optical imaging system. A trypan blue exclusion test and MTT assay were used to evaluate the cytotoxicity of SiQDs to cultured human corneal epithelial cells. No difference was observed between the fluorescence emission of Sc-SiQDs and Cu-SiQDs at any concentration. On average, SiQDs showed stable fluorescence, while Sc-SiQDs and Cu-SiQDs showed brighter fluorescence emissions than Zn-SiQDs. Cu-SiQDs and Sc-SiQDs showed a broader safe concentration range than Zn-SiQDs. Cu-SiQDs and Zn-SiQDs tend to aggregate more substantially in TheraTears® than Sc-SiQDs. This study elucidates the feasibility of hydrophilic Sc-SiQDs in studying the tear film’s aqueous layer

American Academy of Optometry Microbial Keratitis Think Tank

SIGNIFICANCE Think Tank 2019 affirmed that the rate of infection associated with contact lenses has not changed in several decades. Also, there is a trend toward more serious infections associated with Acanthamoeba and fungi. The growing use of contact lenses in children demands our attention with surveillance and case-control studies. PURPOSE The American Academy of Optometry (AAO) gathered researchers and key opinion leaders from around the world to discuss contact lens-associated microbial keratitis at the 2019 AAO Annual Meeting. METHODS Experts presented within four sessions. Session 1 covered the epidemiology of microbial keratitis, pathogenesis of Pseudomonas aeruginosa, and the role of lens care systems and storage cases in corneal disease. Session 2 covered nonbacterial forms of keratitis in contact lens wearers. Session 3 covered future needs, challenges, and research questions in relation to microbial keratitis in youth and myopia control, microbiome, antimicrobial surfaces, and genetic susceptibility. Session 4 covered compliance and communication imperatives. RESULTS The absolute rate of microbial keratitis has remained very consistent for three decades despite new technologies, and extended wear significantly increases the risk. Improved oxygen delivery afforded by silicone hydrogel lenses has not impacted the rates, and although the introduction of daily disposable lenses has minimized the risk of severe disease, there is no consistent evidence that they have altered the overall rate of microbial keratitis. Overnight orthokeratology lenses may increase the risk of microbial keratitis, especially secondary to Acanthamoeba, in children. Compliance remains a concern and a significant risk factor for disease. New insights into host microbiome and genetic susceptibility may uncover new theories. More studies such as case-control designs suited for rare diseases and registries are needed. CONCLUSIONS The first annual AAO Think Tank acknowledged that the risk of microbial keratitis has not decreased over decades, despite innovation. Important questions and research directions remain

TFOS Lifestyle: Impact of nutrition on the ocular surface: TFOS Lifestyle Workshop: Nutrition report

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials

TFOS European Ambassador meeting: Unmet needs and future scientific and clinical solutions for ocular surface diseases

The mission of the Tear Film & Ocular Surface Society (TFOS) is to advance the research, literacy, and educational aspects of the scientific field of the tear film and ocular surface. Fundamental to fulfilling this mission is the TFOS Global Ambassador program. TFOS Ambassadors are dynamic and proactive experts, who help promote TFOS initiatives, such as presenting the conclusions and recommendations of the recent TFOS DEWS II™, throughout the world. They also identify unmet needs, and propose future clinical and scientific solutions, for management of ocular surface diseases in their countries. This meeting report addresses such needs and solutions for 25 European countries, as detailed in the TFOS European Ambassador meeting in Rome, Italy, in September 2019

Characterization of the normal microbiota of the ocular surface

The ocular surface is continually exposed to the environment and as a consequence to different types of microbes, but whether there is a normal microbiota of the ocular surface remains unresolved. Using traditional microbial culture techniques has shown that <80% of swabs of the conjunctiva yield cultivable microbes. These usually belong to the bacterial types of the coagulase-negative staphylococci, Propionibacterium sp., with low frequency of isolation of bacteria such as Staphylococcus aureus, Micrococcus sp., Gram-negative bacteria or fungi. Even when these are grown, the numbers of colony forming units (cfu) per swab of the conjunctiva is usually much less than 100cfu. Swabs of the lid more commonly result in microbial growth, of the same species as from the conjunctiva and slightly higher cfu. Contact lenses have also been cultured, and they yield similar microbial types. Microbes can be isolated from the ocular surface almost immediately after birth. The advent of molecular techniques for microbial identification based on 16S rRNA sequencing has opened up the possibility of determining whether there are non-cultivable microbes that can colonise the ocular surface. Additionally, use of these techniques with cross-sectional and longitudinal studies may help to understand whether the ocular surface harbours its own unique microbiota, or whether the microbiota are only transiently present. © 2013 Elsevier Ltd