September 2020

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Jakobiec FA, Barrantes PC, Yonekawa Y, Lad EM, Proia AD. Subretinal Mononuclear Cells in Coats' Disease Studied with RPE65 and CD163: Evidence for Histiocytoid Pigment Epithelial Cells. Am J Ophthalmol 2020;Abstract
PURPOSE: To evaluate the mononuclear cells in the subretinal exudate in Coats' disease. DESIGN: Retrospective case series. METHODS: Five enucleated globes and one cytology sample with Coats' disease and one case of chronic retinal detachment following repair of an open globe injury were examined immunohistochemically to identify the intraretinal and subretinal exudative cells. The two biomarkers were RPE65 for retinal pigment epithelium and CD163 for histiocytes, each tagged with different chromogens, yellow for pigment epithelium and purple for CD163+ monocytes/histiocytes. Expressions were sought of both biomarkers together or singly. A color shift to red in the cells' chromogenic reaction indicated the simultaneous presence of the two biomarkers. RESULTS: The majority of the mononuclear cells in Coats' disease were CD163 (purple) positive, and a minority were RPE65 (yellow) positive. An intermediate number of cells were RPE65/CD163 positive (orange-red). The eye with a chronic retinal detachment had an equal distribution of CD163 positive and RPE65/CD163 positive cells. CONCLUSIONS: The retinal pigment epithelium has several well-delineated phenotypes and functions. In normal visual physiology, the pigment epithelium supports the photoreceptors and participates in their renewal by phagocytosis of the tips of the photoreceptors. The expression of CD163, a feature of hematopoietically derived monocytes, together with RPE65 in the retinal pigment epithelium, supports differentiation toward histiocytes. Yellow staining detached pigment epithelial cells were rare. The presence of histiocytoid pigment epithelium at the level of Bruch's membrane probably also has implications for macular degeneration.
Jamali A, Hu K, Sendra VG, Blanco T, Lopez MJ, Ortiz G, Qazi Y, Zheng L, Turhan A, Harris DL, Hamrah P. Characterization of Resident Corneal Plasmacytoid Dendritic Cells and Their Pivotal Role in Herpes Simplex Keratitis. Cell Rep 2020;32(9):108099.Abstract
The presence and potential functions of resident plasmacytoid dendritic cells (pDCs) in peripheral tissues is unclear. We report that pDCs constitutively populate naïve corneas and are increased during sterile injuries or acute herpes simplex virus 1 (HSV-1) keratitis. Their local depletion leads to severe clinical disease, nerve loss, viral dissemination to the trigeminal ganglion and draining lymph nodes, and mortality, while their local adoptive transfer limits disease. pDCs are the main source of HSV-1-induced IFN-α in the corneal stroma through TLR9, and they prevent re-programming of regulatory T cells (Tregs) to effector ex-Tregs. Clinical signs of infection are observed in pDC-depleted corneas, but not in pDC-sufficient corneas, following low-dose HSV-1 inoculation, suggesting their critical role in corneal antiviral immunity. Our findings demonstrate a vital role for corneal pDCs in the control of local viral infections.
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Khalil IA, Saleh B, Ibrahim DM, Jumelle C, Yung A, Dana R, Annabi N. Ciprofloxacin-loaded bioadhesive hydrogels for ocular applications. Biomater Sci 2020;8(18):5196-5209.Abstract
The management of corneal infections often requires complex therapeutic regimens involving the prolonged and high-frequency application of antibiotics that provide many challenges to patients and impact compliance with the therapeutic regimens. In the context of severe injuries that lead to tissue defects (e.g. corneal lacerations) topical drug regimens are inadequate and suturing is often indicated. There is thus an unmet need for interventions that can provide tissue closure while concurrently preventing or treating infection. In this study, we describe the development of an antibacterial bioadhesive hydrogel loaded with micelles containing ciprofloxacin (CPX) for the management of corneal injuries at risk of infection. The in vitro release profile showed that the hydrogel system can release CPX, a broad-spectrum antibacterial drug, for up to 24 h. Moreover, the developed CPX-loaded hydrogels exhibited excellent antibacterial properties against Staphylococcus aureus and Pseudomonas aeruginosa, two bacterial strains responsible for the most ocular infections. Physical characterization, as well as adhesion and cytocompatibility tests, were performed to assess the effect of CPX loading in the developed hydrogel. Results showed that CPX loading did not affect stiffness, adhesive properties, or cytocompatibility of hydrogels. The efficiency of the antibacterial hydrogel was assessed using an ex vivo model of infectious pig corneal injury. Corneal tissues treated with the antibacterial hydrogel showed a significant decrease in bacterial colony-forming units (CFU) and a higher corneal epithelial viability after 24 h as compared to non-treated corneas and corneas treated with hydrogel without CPX. These results suggest that the developed adhesive hydrogel system presents a promising suture-free solution to seal corneal wounds while preventing infection.
Koulouri I, Hellwinkel O, Altenähr S, Spitzer M, Fritz S, Feuerstacke J, Filev F. A new storage solution for the hypothermic preservation of corneal grafts: an experimental study. Cell Tissue Bank 2020;21(3):507-521.Abstract
In this experimental study we used for the first time Tiprotec as a solution for corneal preservation and cold storage. We compared the resultant endothelial cell morphology and viability with this obtained after preservation of the ex-vivo corneas with both usual standard techniques: conventional cold storage (using Eusol-C) and organ culture. This prospective, in vitro, 3-armed parallel study was performed with the use of 90 porcine corneas (examined for their endothelial quality and transparency) randomly selected for preservation in three storage methods (each 30 corneas): organ culture, standard cold storage (Eusol-C) and experimental cold storage (Tiprotec) Endothelium cell quantity and quality as well as corneal opacification were assessed. The degree of endothelial transparency was significantly reduced over time with all preservation media, without any significant difference among the three groups at any point of time. A reduction in endothelial cell density was also observed with all three preservation media after 30 days of storage without statistically significant differences between groups. The number of hexagonal and pentagonal endothelium cells was significantly reduced overtime in all media with significantly more hexagonal and pentagonal in the organ culture group compared to the cold storage groups. We could show that the cryopreservation medium Tiprotec, used until now for the preservation of vascular grafts, was of similar quality compared to the medium Eusol-C for the hypothermic storage of corneal tissue for an extended period of time up to 30 days. In comparison to organic culture with culture medium KII, both Tiprotec and Eusol-C were found less effective in preserving endothelial cell quality, as assessed by the morphometric analysis, and viability, as assessed by the degree of vacuolization at least up to the 30th day of storage. However, both, Tiprotec- and Eusol-C-preserved corneas demonstrated a certain capacity to recover after their submission in organ culture.
Kras A, Celi LA, Miller JB. Accelerating ophthalmic artificial intelligence research: the role of an open access data repository. Curr Opin Ophthalmol 2020;31(5):337-350.Abstract
PURPOSE OF REVIEW: Artificial intelligence has already provided multiple clinically relevant applications in ophthalmology. Yet, the explosion of nonstandardized reporting of high-performing algorithms are rendered useless without robust and streamlined implementation guidelines. The development of protocols and checklists will accelerate the translation of research publications to impact on patient care. RECENT FINDINGS: Beyond technological scepticism, we lack uniformity in analysing algorithmic performance generalizability, and benchmarking impacts across clinical settings. No regulatory guardrails have been set to minimize bias or optimize interpretability; no consensus clinical acceptability thresholds or systematized postdeployment monitoring has been set. Moreover, stakeholders with misaligned incentives deepen the landscape complexity especially when it comes to the requisite data integration and harmonization to advance the field. Therefore, despite increasing algorithmic accuracy and commoditization, the infamous 'implementation gap' persists. Open clinical data repositories have been shown to rapidly accelerate research, minimize redundancies and disseminate the expertise and knowledge required to overcome existing barriers. Drawing upon the longstanding success of existing governance frameworks and robust data use and sharing agreements, the ophthalmic community has tremendous opportunity in ushering artificial intelligence into medicine. By collaboratively building a powerful resource of open, anonymized multimodal ophthalmic data, the next generation of clinicians can advance data-driven eye care in unprecedented ways. SUMMARY: This piece demonstrates that with readily accessible data, immense progress can be achieved clinically and methodologically to realize artificial intelligence's impact on clinical care. Exponentially progressive network effects can be seen by consolidating, curating and distributing data amongst both clinicians and data scientists.
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Lei F, Cui N, Zhou C, Chodosh J, Vavvas DG, Paschalis EI. CSF1R inhibition by a small-molecule inhibitor is not microglia specific; affecting hematopoiesis and the function of macrophages. Proc Natl Acad Sci U S A 2020;117(38):23336-23338.Abstract
Colony-stimulating factor 1 receptor (CSF1R) inhibition has been proposed as a method for microglia depletion, with the assumption that it does not affect peripheral immune cells. Here, we show that CSF1R inhibition by PLX5622 indeed affects the myeloid and lymphoid compartments, causes long-term changes in bone marrow-derived macrophages by suppressing interleukin 1β, CD68, and phagocytosis but not CD208, following exposure to endotoxin, and also reduces the population of resident and interstitial macrophages of peritoneum, lung, and liver but not spleen. Thus, small-molecule CSF1R inhibition is not restricted to microglia, causing strong effects on circulating and tissue macrophages that perdure long after cessation of the treatment. Given that peripheral monocytes repopulate the central nervous system after CSF1R inhibition, these changes have practical implications for relevant experimental data.
Lužnik Z, Sun Z, Nakagawa H, Taylor AW, Jurkunas UV, Yin J, Dana R. Association of α-Melanocyte-Stimulating Hormone With Corneal Endothelial Cell Survival During Oxidative Stress and Inflammation-Induced Cell Loss in Donor Tissue. JAMA Ophthalmol 2020;Abstract
Importance: Corneal endothelial cell (CEnC) damage and loss are major issues in eye banking and transplantation. The underlying mechanisms for CEnC loss are incompletely understood, and cytoprotective strategies that enhance CEnC viability could have a major effect on donor tissue quality and graft survival. Objective: To investigate the cytoprotective role of neuropeptide α-melanocyte-stimulating hormone (α-MSH) in preventing CEnC loss in eye bank cold-stored corneas under oxidative and inflammatory cytokine-induced stress. Design, Setting, and Participants: This single-center comparative research study conducted ex vivo experiments using 16 pairs of research-grade human donor corneas (courtesy of Eversight Eye Bank). Data were collected from June 2018 to November 2019, and data were analyzed from December 2019 to January 2020. Exposures: Two corneas from the same donor were randomized to either control or 0.1 mmol/L of α-MSH treatment and then subjected to oxidative stress (1.4 mmol/L of hydrogen peroxide-phosphate-buffered saline for 15 minutes at 37 °C; n = 8 pairs) or cytokine-induced stress (100 ng/mL of tumor necrosis factor-α and 100 ng/mL of interferon γ for 18 hours at 37 °C; n = 8 pairs). Corneas were then stored at 4 °C. Specular images were taken at baseline and repeated twice per week using a calibrated wide-field specular microscope. CEnC viability was assessed using a fluorescent live/dead viability assay. Main Outcome and Measures: Endothelial morphometry analysis, central corneal thickness measurements, and percentage of dead cells at day 11. Results: Of 16 donors who provided corneas, 9 (56%) were male, and the mean (SD) age was 57.9 (12.4) years. Corneas were paired, and baseline parameters were comparable between all groups. At all time points, CEnC loss was lower in the α-MSH groups compared with the control groups. This difference was statistically significant after cytokine-induced stress (20.2% vs 35.2%; sample estimate of median, -14.9; 95% CI, -23.6 to -6.3; P = .008). Compared with the control group, α-MSH treatment resulted in a smaller increase in central corneal thickness (cytokine-induced stress: 89.3 μm vs 169.8 μm; sample estimate of median, -84.9; 95% CI, -131.5 to -41.6; P = .008; oxidative stress: 43.6 μm vs 111.9 μm; sample estimate of median, -68.8; 95% CI, -100.0 to -34.5; P = .008) and a smaller proportion of cell death (cytokine-induced stress: 2.7% vs 10.4%; difference, -7.7; 95% CI, -13.1 to -2.4; P = .01; oxidative stress: 2.9% vs 12.4%; difference, 9.5; 95% CI, 5.1 to 13.9; P = .006). Conclusions and Relevance: In this study, α-MSH treatment attenuated CEnC loss during cold storage after acute oxidative and cytokine-induced stress in human eye bank cold-stored corneas. These data suggest that supplementation of corneal storage solution with α-MSH may positively affect CEnC survival after transplant and protect the endothelium from proinflammatory cytokines and oxidative stress after full-thickness or endothelial keratoplasty, which is particularly valuable in patients at high risk of graft failure.
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Maleki A, Gomez S, Asgari S, Bosenberg Z, Manhapra A, Walsh M, Weng A, Tseng C, He C, Anesi SD, Foster SC. Diagnostic and Prognostic Roles of Serum Interleukin-6 Levels in Patients with Uveitis. Ocul Immunol Inflamm 2020;:1-6.Abstract
PURPOSE: To examine the diagnostic and prognostic roles of serum interleukin-6 levels in patients with uveitis. METHODS: This was a retrospective observational case series. Demographic and clinical characteristics were compared between Group One (sixty patients) with normal serum IL-6 levels and Group Two (twenty patients) with high serum interleukin-6 levels. RESULTS: Mean IL-6 level was 1.77 ± 0.97 pg/ml and 10.2 ± 9.7 pg/ml in Group One and Group Two respectively. Age, presence of systemic disease, and mean number of flare-ups were statistically significant ( = .015, = .000, = .03, respectively). Multivariate analysis was performed on variables that were statistically significant in univariate analysis and showed that three variables had significant correlation with IL-6 levels in both groups: systemic disease (OR = 10.83, < .001), Age (OR = 0.95, = .03) and number of flare-ups (OR = 2.9, = .02). CONCLUSION: Serum IL-6 levels can provide diagnostic and prognostic information in regard to the course of disease and its treatment.
Milman T, Jakobiec FA, Lally SE, Shields JA, Shields CL, Eagle RC. Lacrimal Gland Hamartoma (Formerly Termed Dacryoadenoma). Am J Ophthalmol 2020;217:189-197.Abstract
PURPOSE: Since the original description of "dacryadenoma" by Jakobiec and associates, the data on this unusual epibulbar lacrimal gland lesion remain sparse. The aim of this study was to characterize clinically, morphologically, and immunohistochemically this isolated epibulbar lacrimal gland lesion. DESIGN: Retrospective observational case series. METHODS: Institutional pathology records between 2000 and 2019 were searched for all cases of isolated epibulbar lacrimal gland lesions. Tissue from 3 normal lacrimal glands and 1 complex choristoma were included for comparative analysis. Clinical, histopathologic, and immunohistochemical findings were recorded. RESULTS: Four patients with isolated epibulbar lacrimal gland lesions, 2 male and 2 female, with a median age of 18 years (range, 12-57) were identified. All patients presented with recent onset of unilateral pink-to-orange, well-circumscribed subepithelial juxtaforniceal (3/4, 75%), or nasal (1/4, 25%) bulbar conjunctival nodules, which were asymptomatic (3/4, 75%) or associated with foreign body sensation (1/4, 25%). When compared with the normal lacrimal gland and complex choristoma, all isolated epibulbar lacrimal gland lesions were composed predominantly of variably dilated, branching tubular structures with pseudo-apocrine snouts, and either totally absent (2/2, 50%) or rare (2/2, 50%) ducts and rare acinar zymogen granules (3/4, 75%). CONCLUSION: Our study confirms that a subset of isolated epibulbar lacrimal gland lesions differs morphologically and immunohistochemically from normal lacrimal gland tissue and the lacrimal gland in a complex choristoma. These differences range from subtle to overt, suggesting that isolated epibulbar lacrimal gland lesions may have originated from precursor cellular elements indigenous to the conjunctiva (hamartia) and grew into disorganized lacrimal gland tissue.
Minaeva O, Sarangi S, Ledoux DM, Moncaster JA, Parsons DS, Washicosky KJ, Black CA, Weng FJ, Ericsson M, Moir RD, Tripodis Y, Clark JI, Tanzi RE, Hunter DG, Goldstein LE. In Vivo Quasi-Elastic Light Scattering Eye Scanner Detects Molecular Aging in Humans. J Gerontol A Biol Sci Med Sci 2020;75(9):e53-e62.Abstract
The absence of clinical tools to evaluate individual variation in the pace of aging represents a major impediment to understanding aging and maximizing health throughout life. The human lens is an ideal tissue for quantitative assessment of molecular aging in vivo. Long-lived proteins in lens fiber cells are expressed during fetal life, do not undergo turnover, accumulate molecular alterations throughout life, and are optically accessible in vivo. We used quasi-elastic light scattering (QLS) to measure age-dependent signals in lenses of healthy human subjects. Age-dependent QLS signal changes detected in vivo recapitulated time-dependent changes in hydrodynamic radius, protein polydispersity, and supramolecular order of human lens proteins during long-term incubation (~1 year) and in response to sustained oxidation (~2.5 months) in vitro. Our findings demonstrate that QLS analysis of human lens proteins provides a practical technique for noninvasive assessment of molecular aging in vivo.
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Narayanan D, Wallstrom G, Rodriguez J, Welch D, Chapin M, Arrigg P, Patil R, Abelson M. Early Ophthalmic Changes in Macula Does Not Correlate with Visual Function. Clin Ophthalmol 2020;14:2571-2576.Abstract
Purpose: Early detection and treatment of age-related macular degeneration require a clear understanding of the early progress of the disease. The purpose of this study was to investigate whether minimal macular ophthalmoscopic changes corresponded to changes in visual function. Methods: Color macular photos from a group of older subjects who were classified as grade 0 on AREDS simplified grading were further evaluated by a retinal specialist using 5x magnification for possible minimal macular anomalies. Group 0-A ( = 15) were defined as subjects with no visible macular anomalies while Group 0-B ( = 19) comprised subjects for whom minimal macular mottling, pigment changes or very small drusen (< 63 µm) were observed in the study eye. All subjects had best VA of 20/25 or better and had no evidence of other retinal diseases in the study eye. All subjects underwent a series of visual function tests such as standard ETDRS VA, low luminance ETDRS VA, Pelli-Robson contrast sensitivity, variable contrast flicker (VCF) sensitivity, and reading speed (words per minute, wpm) using both MNRead and low luminance reading on a tablet. Results: There was no significant difference between the mean age between the two groups (74.8 ± 5.2 years for 0-A vs 74.5 ± 4.4 for 0-B, = 0.82). None of the visual function tests identified any significant difference between the two groups. Mean ETDRS VA was 0.0 ± 0.11 for 0-A subjects and 0.08 ± 0.12 for 0-B ( = 0.063). Mean Pelli-Robson log contrast sensitivity was 1.75 ± 0.29 for 0-A and 1.78 ± 0.17 for the 0-B group ( = 0.73). VCF threshold was 0.47 ± 0.25 for 0-A and 0.43 ± 0.22 for 0-B ( = 0.64). Reading speed using MNRead was 214 ± 47.4 wpm for 0-A and 210 ± 64.7 for 0-B ( = 0.85). Low luminance tablet reading speed was 137 ± 71.8 wpm for 0-A and 151 ± 39.4 (0-B) ( = 0.49). Conclusion: A panel of psychophysical tests did not demonstrate significant differences between subjects with and without minimal macular changes.
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Ozulken K, Ilhan C, Yuksel E, Mumcuoglu T. Preliminary effects of treating the half of high latent hyperopia on refractive and visual results of femtosecond laser-assisted in situ keratomileusis in subjects with hyperopia. Int Ophthalmol 2020;40(9):2361-2369.Abstract
BACKGROUND: To evaluate the preliminary effects of treating the half of high latent hyperopia on refractive and visual outcomes of femtosecond laser-assisted in situ keratomileusis (LASIK) in young subjects with hyperopia. METHODS: This non-randomized comparative study includes 120 eyes of 60 subjects who underwent femtosecond LASIK to correct hyperopia. Group 1 (n = 60) includes subjects with ≤ 1D algebraic difference (DRSE) between cycloplegic (CRSE) and manifest (MRSE) refraction spherical equivalents and was treated by entering manifest refraction values. Group 2 includes subjects with > 1D DRSE and was treated by entering the mean manifest and cycloplegic refraction values. Refractive and subjective outcomes obtained at the 1-, 3-, and 6-month postoperative visits were compared. RESULTS: The mean age of the subjects was 26.2 ± 3.5 and 26.2 ± 5.2 years for Group 1 and Group 2, respectively. The male-to-female ratios were 10/10 in both groups. Demographic values of the groups were similar (p > 0.05). Preoperative MRSE values were similar (p = 0.924), while CRSE and DRSE values were significantly higher in Group 2 (p < 0.001). At the 1- and 3-month postoperative visits, MRSE was higher and uncorrected distance visual acuity (UDVA) was lower in Group 2 (p < 0.001). Subjective visual parameters and quality of vision scores were also worse in Group 2 during these visits (p < 0.001); however, at the 6-month visit, all outcomes for Group 2 improved, and MRSE, UDVA, some subjective visual parameters, and quality of vision scores became similar between groups (p > 0.05). CONCLUSION: At the 6-month visit after treating the half of > 1D latent hyperopia with femtosecond LASIK, refractive and visual outcomes like MRSE, UDVA, subjective visual parameters, and quality of vision scores become similar to those obtained in ≤ 1D latent hyperopia.
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Park EA, Tsikata E, Lee JJ, Shieh E, Braaf B, Vakoc BJ, Bouma BE, de Boer JF, Chen TC. Artifact Rates for 2D Retinal Nerve Fiber Layer Thickness Versus 3D Neuroretinal Rim Thickness Using Spectral-Domain Optical Coherence Tomography. Transl Vis Sci Technol 2020;9(10):10.Abstract
Purpose: To compare the rates of clinically significant artifacts for two-dimensional peripapillary retinal nerve fiber layer (RNFL) thickness versus three-dimensional (3D) neuroretinal rim thickness using spectral-domain optical coherence tomography (SD-OCT). Methods: Only one eye per patient was used for analysis of 120 glaucoma patients and 114 normal patients. For RNFL scans and optic nerve scans, 15 artifact types were calculated per B-scan and per eye. Neuroretinal rim tissue was quantified by the minimum distance band (MDB). Global MDB neuroretinal rim thicknesses were calculated before and after manual deletion of B-scans with artifacts and subsequent automated interpolation. A clinically significant artifact was defined as one requiring manual correction or repeat scanning. Results: Among glaucomatous eyes, artifact rates per B-scan were significantly more common in RNFL scans (61.7%, 74 of 120) compared to B-scans in neuroretinal rim volume scans (20.9%, 1423 of 6820) (95% confidence interval [CI], 31.6-50.0; < 0.0001). For clinically significant artifact rates per eye, optic nerve scans had significantly fewer artifacts (15.8% of glaucomatous eyes, 13.2% of normal eyes) compared to RNFL scans (61.7% of glaucomatous eyes, 25.4% of normal eyes) (glaucoma group: 95% CI, 34.1-57.5, < 0.0001; normal group: 95% CI, 1.3-23.3, = 0.03). Conclusions: Compared to the most commonly used RNFL thickness scans, optic nerve volume scans less frequently require manual correction or repeat scanning to obtain accurate measurements. Translational Relevance: This paper illustrates the potential for 3D OCT algorithms to improve in vivo imaging in glaucoma.
Prichula J, Van Tyne D, Schwartzman J, Sant'Anna FH, Pereira RI, da Cunha GR, Tavares M, Lebreton F, Frazzon J, d'Azevedo PA, Seixas A, Frazzon APG, Gilmore MS. Enterococci from Wild Magellanic Penguins (Spheniscus magellanicus) as an Indicator of Marine Ecosystem Health and Human Impact. Appl Environ Microbiol 2020;86(19)Abstract
Enterococci are commensals that proliferated as animals crawled ashore hundreds of millions of years ago. They are also leading causes of multidrug-resistant hospital-acquired infections. While most studies are driven by clinical interest, comparatively little is known about enterococci in the wild or the effect of human activity on them. Pharmaceutical pollution and runoff from other human activities are encroaching widely into natural habitats. To assess their reach into remote habitats, we investigated the identity, genetic relatedness, and presence of specific traits among 172 enterococcal isolates from wild Magellanic penguins. Four enterococcal species, 18 lineage groups, and different colonization patterns were identified. One lineage, sequence type 475 (ST475), was isolated from three different penguins, making it of special interest. Its genome was compared to those of other sequence types (ST116 and ST242) recovered from Magellanic penguins, as well as to an existing phylogeny of isolated from diverse origins over the past 100 years. No penguin-derived strains were closely related to dominant clinical lineages. Most possessed intact CRISPR defenses, few mobile elements, and antibiotic resistances limited to those intrinsic to the species and lacked pathogenic features conveyed by mobile elements. Interestingly, plasmids were identified in penguin isolates that also had been reported for other marine mammals. Enterococci isolated from penguins showed limited anthropogenic impact, indicating that they are likely representative of those naturally circulating in the ecosystem inhabited by the penguins. These findings establish an important baseline for detecting the encroachment of human activity into remote planetary environments. Enterococci are host-associated microbes that have an unusually broad range, from the built hospital environment to the guts of insects and other animals in remote locations. Despite their occurrence in the guts of animals for hundreds of millions of years, we know little about the properties that confer this range or how anthropogenic activities may be introducing new selective forces. Magellanic penguins live at the periphery of human habitation. It was of interest to examine enterococci from these animals for the presence of antibiotic resistance and other markers reflective of anthropogenic selection. Diverse enterococcal lineages found discount the existence of a single well-adapted intrinsic penguin-specific species. Instead, they appear to be influenced by a carnivorous lifestyle and enterococci present in the coastal sea life consumed. These results indicate that currently, the penguin habitat remains relatively free of pollutants that select for adaptation to human-derived stressors.
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Rabe BA, Cepko C. SARS-CoV-2 detection using isothermal amplification and a rapid, inexpensive protocol for sample inactivation and purification. Proc Natl Acad Sci U S A 2020;Abstract
The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had an enormous impact on society worldwide, threatening the lives and livelihoods of many. The effects will continue to grow and worsen if economies begin to open without the proper precautions, including expanded diagnostic capabilities. To address this need for increased testing, we have developed a sensitive reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay compatible with current reagents, which utilizes a colorimetric readout in as little as 30 min. A rapid inactivation protocol capable of inactivating virions, as well as endogenous nucleases, was optimized to increase sensitivity and sample stability. This protocol, combined with the RT-LAMP assay, has a sensitivity of at least 50 viral RNA copies per microliter in a sample. To further increase the sensitivity, a purification protocol compatible with this inactivation method was developed. The inactivation and purification protocol, combined with the RT-LAMP assay, brings the sensitivity to at least 1 viral RNA copy per microliter in a sample. This simple inactivation and purification pipeline is inexpensive and compatible with other downstream RNA detection platforms and uses readily available reagents. It should increase the availability of SARS-CoV-2 testing as well as expand the settings in which this testing can be performed.
Razeghinejad R, Lin MM, Lee D, Katz JL, Myers JS. Pathophysiology and management of glaucoma and ocular hypertension related to trauma. Surv Ophthalmol 2020;65(5):530-547.Abstract
Ocular trauma is a significant cause of blindness worldwide, particularly if associated with glaucoma. Direct damage from blunt or penetrating trauma, bleeding, inflammation, lens-related problems, orbital and brain vascular pathologies related to trauma, and chemical injuries may increase intraocular pressure and lead to traumatic glaucoma. Treatment may be as simple as eliminating the underlying cause in some conditions or management can be challenging, depending on the mechanism of damage. If proper management is not undertaken, visual outcomes can be poor. We discuss a broad spectrum of trauma-related mechanisms of intraocular pressure elevation, as well as their management.
Rinaldi L, Ciricugno A, Merabet LB, Vecchi T, Cattaneo Z. The Effect of Blindness on Spatial Asymmetries. Brain Sci 2020;10(10)Abstract
The human cerebral cortex is asymmetrically organized with hemispheric lateralization pervading nearly all neural systems of the brain. Whether the lack of normal visual development affects hemispheric specialization subserving the deployment of visuospatial attention asymmetries is controversial. In principle, indeed, the lack of early visual experience may affect the lateralization of spatial functions, and the blind may rely on a different sensory input compared to the sighted. In this review article, we thus present a current state-of-the-art synthesis of empirical evidence concerning the effects of visual deprivation on the lateralization of various spatial processes (i.e., including line bisection, mirror symmetry, and localization tasks). Overall, the evidence reviewed indicates that spatial processes are supported by a right hemispheric network in the blind, hence, analogously to the sighted. Such a right-hemisphere dominance, however, seems more accentuated in the blind as compared to the sighted as indexed by the greater leftward bias shown in different spatial tasks. This is possibly the result of the more pronounced involvement of the right parietal cortex during spatial tasks in blind individuals compared to the sighted, as well as of the additional recruitment of the right occipital cortex, which would reflect the cross-modal plastic phenomena that largely characterize the blind brain.
Rossato FA, Su Y, Mackey A, Ng YSE. Fibrotic Changes and Endothelial-to-Mesenchymal Transition Promoted by VEGFR2 Antagonism Alter the Therapeutic Effects of VEGFA Pathway Blockage in a Mouse Model of Choroidal Neovascularization. Cells 2020;9(9)Abstract
Many patients with wet age-related macular degeneration do not respond well to anti- vascular endothelial growth factor A (VEGFA) therapy for choroidal neovascularization (CNV), and the efficacy of anti-VEGFA decreases over time. We investigated the hypothesis that fibrotic changes, in particular via endothelial-to-mesenchymal transition (EndoMT), play a role in CNV and alter the therapeutic effects of VEGFA pathway blockage. Induction of EndoMT of primary human retinal endothelial cells led to a significantly reduced response to VEGFA at the level of gene expression, cellular proliferation, migration, and tube formation. Suppression of EndoMT restored cell responsiveness to VEGFA. In a mouse model of spontaneous CNV, fibrotic changes and EndoMT persisted as the CNV lesions became more established over time. VEGFA receptor-2 (VEGFR2) antagonism further induced fibrosis and EndoMT in the CNV. The combination of VEGFR2 antagonism and fibrosis/EndoMT inhibition was more effective than either individual treatment in reducing CNV. Our data indicate that fibrosis and EndoMT are involved in the progression of CNV, are exacerbated by VEGFR2 inhibition, and could provide an explanation for the reduced efficacy of anti-VEGFA treatment over time.
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Sandhu HS, Hemmati HD, Dana R. Immune checkpoint inhibitors and corneal transplant rejection: a call for awareness. Immunotherapy 2020;12(13):947-949.
Sudharshan S, Nair N, Curi A, Banker A, Kempen JH. Human immunodeficiency virus and intraocular inflammation in the era of highly active anti retroviral therapy - An update. Indian J Ophthalmol 2020;68(9):1787-1798.Abstract
Intraocular inflammation in patients with human immunodeficiency virus (HIV) infection is commonly due to infectious uveitis. Ocular lesions due to opportunistic infections (OI) are the most common and have been described extensively in the pre highly active antiretroviral therapy (HAART) era. Many eye lesions were classified as acquired immunodeficiency syndrome (AIDS) defining illnesses. HAART-associated improvement in immunity of the individual has changed the pattern of incidence of these hitherto reported known lesions leading to a marked reduction in the occurrence of ocular OI. Newer ocular lesions and newer ocular manifestations of known agents have been noted. Immune recovery uveitis (IRU), the new menace, which occurs as part of immune recovery inflammatory syndrome (IRIS) in the eye, can present with significant ocular inflammation and can pose a diagnostic and therapeutic challenge. Balancing the treatment of inflammation with the risk of reactivation of OI is a task by itself. Ocular involvement in the HAART era can be due to the adverse effects of some systemic drugs used in the management of HIV/AIDS. Drug-associated retinal toxicity and other ocular side effects are being increasingly reported. In this review, we discuss the ocular manifestations in HIV patients and its varied presentations following the introduction of HAART, drug-associated lesions, and the current treatment guidelines.

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