Direct enzymatic sequencing of 5-methylcytosine at single-base resolution.

5-methylcytosine (5mC) is the most important DNA modification in mammalian genomes. The ideal method for 5mC localization would be both nondestructive of DNA and direct, without requiring inference based on detection of unmodified cytosines. Here we present direct methylation sequencing (DM-Seq), a bisulfite-free method for profiling 5mC at single-base resolution using nanogram quantities of DNA. DM-Seq employs two key DNA-modifying enzymes: a neomorphic DNA methyltransferase and a DNA deaminase capable of precise discrimination between cytosine modification states. Coupling these activities with deaminase-resistant adapters enables accurate detection of only 5mC via a C-to-T transition in sequencing. By comparison, we uncover a PCR-related underdetection bias with the hybrid enzymatic-chemical TET-assisted pyridine borane sequencing approach. Importantly, we show that DM-Seq, unlike bisulfite sequencing, unmasks prognostically important CpGs in a clinical tumor sample by not confounding 5mC with 5-hydroxymethylcytosine. DM-Seq thus offers an all-enzymatic, nondestructive, faithful and direct method for the reading of 5mC alone.

A comparative study of stereopsis in term and preterm children with and without retinopathy of prematurity.

PURPOSE: To evaluate stereopsis in term-born, preterm, and preterm children with and without retinopathy of prematurity (ROP) and its treatment. METHODS: The cross-sectional study included 322 children between 3 and 11 years of age born term or preterm, with or without ROP, and with or without treatment for ROP. The ROP treatments were laser therapy, intravitreal injection (IVI) of anti-vascular endothelial growth factor, or their combination. Stereoacuity was measured using the Titmus Stereo Test, and the results among various age groups were analyzed. RESULTS: Stereopsis was found to improve with increasing age at testing (P < 0.001) across the entire study population. The term group exhibited significantly better stereoacuity than the preterm group (P < 0.001). At 3-5 years and 6-8 years, the preterm children without ROP exhibited significantly better stereoacuity than did those with ROP (P < 0.001 and P = 0.02, respectively); however, at 9-11 years, both groups exhibited similar stereoacuity (P = 0.34). The stereoacuity in the children with untreated ROP was similar to that of the children with treated ROP in all age groups (P > 0.05). No significant differences in stereopsis were identified between children with ROP treated with laser versus with IVI (P > 0.05). From multivariate analysis, younger age at testing (P = 0.001) and younger gestational age (P < 0.001) were associated with poorer stereopsis. CONCLUSIONS: Stereopsis development gradually improved with age in all groups. The children born preterm exhibited poorer stereoacuity than those born term. Children with ROP treated with laser photocoagulation versus IVI may exhibit similar levels of stereoacuity. Younger age at testing and gestational age were independent risk factors for poorer stereoacuity.

LONGITUDINAL CHANGES IN CHOROIDAL THICKNESS IN CHILDREN WITH A HISTORY OF PREMATURITY: An 18-Month Prospective Cohort Study.

PURPOSE: To evaluate choroidal changes over time in school-age children with a history of prematurity. METHODS: A study of 416 eyes of 208 eligible participants, including 88, 190, 36, 56, and 46 eyes in the full-term control, preterm, spontaneously regressed retinopathy of prematurity, intravitreal bevacizumab (injection of bevacizumab)-treated retinopathy of prematurity, and laser-treated retinopathy of prematurity groups, respectively, were enrolled in this study. The choroidal thickness was measured 4 times at 6-month intervals using optical coherence tomography. RESULTS: Of all the groups, the laser-treated children had the thinnest choroid compared with full-term children (-52.3 µ m, P = 0.04). Preterm children exhibited greater attenuation in choroidal thickness over time than did full-term children (-6.3 ± 26.9 and -1.1 ± 12.8 µ m/year, P = 0.03), whereas no difference was observed between injection of bevacizumab and laser treatments (-4.6 ± 18.9 and -2.0 ± 15.7 µ m/year, P = 0.46). In all groups, the changes in axial length were negatively associated with the changes in choroidal thickness (all P < 0.05). CONCLUSION: A greater attenuation in choroid thickness over time was observed in preterm children than in full-term children, but this attenuation did not differ between injection of bevacizumab and laser treatments. Axial elongation was associated with choroidal thinning in school-age children.

Diagnostic accuracy of eHealth literacy measurement tools in older adults: a systematic review.

BACKGROUND: In Canada, virtual health care rapidly expanded during the COVID-19 pandemic. There is substantial variability between older adults in terms of digital literacy skills, which precludes equitable participation of some older adults in virtual care. Little is known about how to measure older adults' electronic health (eHealth) literacy, which could help healthcare providers to support older adults in accessing virtual care. Our study objective was to examine the diagnostic accuracy of eHealth literacy tools in older adults. METHODS: We completed a systematic review examining the validity of eHealth literacy tools compared to a reference standard or another tool. We searched MEDLINE, EMBASE, CENTRAL/CDSR, PsycINFO and grey literature for articles published from inception until January 13, 2021. We included studies where the mean population age was at least 60 years old. Two reviewers independently completed article screening, data abstraction, and risk of bias assessment using the Quality Assessment for Diagnostic Accuracy Studies-2 tool. We implemented the PROGRESS-Plus framework to describe the reporting of social determinants of health. RESULTS: We identified 14,940 citations and included two studies. Included studies described three methods for assessing eHealth literacy: computer simulation, eHealth Literacy Scale (eHEALS), and Transactional Model of eHealth Literacy (TMeHL). eHEALS correlated moderately with participants' computer simulation performance (r = 0.34) and TMeHL correlated moderately to highly with eHEALS (r = 0.47-0.66). Using the PROGRESS-Plus framework, we identified shortcomings in the reporting of study participants' social determinants of health, including social capital and time-dependent relationships. CONCLUSIONS: We found two tools to support clinicians in identifying older adults' eHealth literacy. However, given the shortcomings highlighted in the validation of eHealth literacy tools in older adults, future primary research describing the diagnostic accuracy of tools for measuring eHealth literacy in this population and how social determinants of health impact the assessment of eHealth literacy is needed to strengthen tool implementation in clinical practice. PROTOCOL REGISTRATION: We registered our systematic review of the literature a priori with PROSPERO (CRD42021238365).

Retrospective Analysis of Surgical Outcomes on Axial Length Elongation in Eyes with Posterior and Combined Persistent Fetal Vasculature.

This study aims to investigate the outcomes and risk factors associated with poor vision (vision less than counting fingers, 2.0 logMAR, Snellen vision 20/2000) in patients with posterior or combined persistent fetal vasculature (PFV), with or without surgery. We retrospectively reviewed the medical records of patients who were diagnosed with PFV from January 2008 to April 2021. We included 51 eyes of 44 patients who presented with PFV, of which 38 eyes underwent surgical correction (pars plicata/plana vitrectomy, with or without lensectomy, and intraocular lens implantation) at the median age of 6.0 months (range: 0.7 to 82.0). The mean follow-up was 68.8 months ± 38.0 months. The axial length change in the eyes undergoing surgery was significantly higher than the eyes without surgery (p = 0.025). Initial anterior chamber collapse and retinal detachment were associated with poor vision (p = 0.006 and p = 0.002, respectively). In addition, 37% of eyes with posterior or combined PFV had vision better than counting fingers. Surgery for eyes with PFV could result in better eye growth. Visual outcomes remained poor and were associated with the level of macular abnormality. Initial anterior chamber collapse and retinal detachment at presentation were the risk factors for poor visual outcomes. Vitrectomy for selected PFV eyes is valuable and associated with a better cosmetic outcome (better eye growth).

CITED4 Protects Against Adverse Remodeling in Response to Physiological and Pathological Stress.

RATIONALE: Cardiac CITED4 (CBP/p300-interacting transactivators with E [glutamic acid]/D [aspartic acid]-rich-carboxylterminal domain4) is induced by exercise and is sufficient to cause physiological hypertrophy and mitigate adverse ventricular remodeling after ischemic injury. However, the role of endogenous CITED4 in response to physiological or pathological stress is unknown. OBJECTIVE: To investigate the role of CITED4 in murine models of exercise and pressure overload. METHODS AND RESULTS: We generated cardiomyocyte-specific CITED4 knockout mice (C4KO) and subjected them to an intensive swim exercise protocol as well as transverse aortic constriction (TAC). Echocardiography, Western blotting, qPCR, immunohistochemistry, immunofluorescence, and transcriptional profiling for mRNA and miRNA (microRNA) expression were performed. Cellular crosstalk was investigated in vitro. CITED4 deletion in cardiomyocytes did not affect baseline cardiac size or function in young adult mice. C4KO mice developed modest cardiac dysfunction and dilation in response to exercise. After TAC, C4KOs developed severe heart failure with left ventricular dilation, impaired cardiomyocyte growth accompanied by reduced mTOR (mammalian target of rapamycin) activity and maladaptive cardiac remodeling with increased apoptosis, autophagy, and impaired mitochondrial signaling. Interstitial fibrosis was markedly increased in C4KO hearts after TAC. RNAseq revealed induction of a profibrotic miRNA network. miR30d was decreased in C4KO hearts after TAC and mediated crosstalk between cardiomyocytes and fibroblasts to modulate fibrosis. miR30d inhibition was sufficient to increase cardiac dysfunction and fibrosis after TAC. CONCLUSIONS: CITED4 protects against pathological cardiac remodeling by regulating mTOR activity and a network of miRNAs mediating cardiomyocyte to fibroblast crosstalk. Our findings highlight the importance of CITED4 in response to both physiological and pathological stimuli.

COMPARISON BETWEEN ORAL AND INTRAVENOUS ULTRAWIDE-FIELD FLUORESCEIN ANGIOGRAPHY IN THE CLINICAL FOLLOW-UP OF CHILDREN WITH A HISTORY OF RETINOPATHY OF PREMATURITY OR PREMATURITY.

PURPOSE: To compare between oral and intravenous (IV) ultrawide-field fluorescein angiography in pediatric patients with a history of prematurity of retinopathy or prematurity. METHODS: Pediatric patients (<18 year old; n = 107 patients) who underwent ultrawide-field fluorescein angiography for retinopathy of prematurity were categorized into oral and IV fluorescein angiography (FA) groups. Quality of FA images was graded on the order of retinal vessels visible. Reported outcomes were proportions of graded FA images, peak fluorescein intensity, and the time to first dye appearance and to reach peak fluorescence. RESULTS: Image quality analysis revealed that 91.5% of IV FA images had excellent image quality compared with only 55.6% of oral FA images (P < 0.01). There were still 83.3% of oral-contrast images with good or excellent image quality. The average time required for first dye appearance and peak fluorescence were significantly shorter in the IV FA group than in the oral FA group (P < 0.01). Peak intensity was greater in the IV group (141.41 ± 29.09) than in the oral group (111.25 ± 45.68; P < 0.01). Adverse reaction rates were similar between the two groups (P = 0.22). CONCLUSION: Ultrawide-field fluorescein angiography provides excellent-quality imaging of the retina in the pediatric population. Overall, oral FA is still an effective and useful alternative to IV FA in children with prematurity history.

Treatment responses for branch retinal vein occlusion predicted by semi-automated fluorescein angiography quantification.

BACKGROUNDS: Branch retinal vein occlusion (BRVO) is one of the most important causes of visual loss in retinal vascular diseases. The aim of this study is to predict the treatment response of anti-vascular endothelial growth factor (anti-VEGF) therapy in BRVO using semi-automated quantified fluorescein angiography (FA) features. METHODS: This retrospective case-control study enrolled patients with BRVO who are receiving anti-VEGF therapy and have been followed up for > 1 year. Those receiving < 5 anti-VEGF injections in the first year were classified as the responsive group, while those receiving ≥5 injections were the refractory group. The FA images were subjected to semi-automated pre-processing. Fluorescein leakages at the 5-min image were represented by mean gray value over parafoveal and perifoveal regions. FA leakages and central retinal thickness (CRT) on optical coherence tomography (OCT) were used for predicting the treatment response and compared using area under receiver operating characteristic curve (AUC). RESULTS: Eighty-nine patients (56 males, 33 females, mean age 62.5 ± 10.9 years) with BRVO were enrolled. Of the 89 eyes, 47 (53%) were in the responsive group and 42 (47%) were in the refractory group. The refractory group had a significantly higher number of anti-VEGF injections in the first year (5.9 ± 1.6 versus 2.4 ± 1.2, p < 0.001) when compared with that of the responsive group. It had thicker pre-treatment CRT (p = 0.011), post-treatment best CRT (p < 0.001) and CRT at 1-year (p < 0.001). It also had a higher mean gray value over the parafoveal (p < 0.001) and the perifoveal (p < 0.001) regions. The mean gray value over perifoveal (AUC 0.846) and parafovel (AUC 0.818) had significantly larger AUC than that of the pre-treatment OCT (AUC 0.653; p = 0.005 and p = 0.016, respectively) when predicting treatment response. CONCLUSION: The refractory group had a more severe fluorescein leakage over the parafoveal and the perifoveal regions than the responsive group had. Semi-automated quantified FA leakage can be used as a biomarker for the prediction of anti-VEGF treatment response in macular edema due to BRVO.

Case report: novel PCDH15 variant causes usher syndrome type 1F with congenital hearing loss and syndromic retinitis pigmentosa.

BACKGROUND: Usher syndrome (USH) is an autosomal recessive disorder primarily responsible for deaf-blindness. Patients with subtype Usher syndrome type 1 (USH1) typically experience congenital sensorineural hearing loss, abnormal vestibular function, and retinitis pigmentosa (RP). Here we present a case of Usher syndrome type 1F (USH1F) with a novel homozygous variant in the calcium-dependent cell-cell adhesion protocadherin-15 (PCDH15) gene. CASE PRESENTATION: Ophthalmic examinations were evaluated over a course of 10 years and the disease-causing variant was identified by whole exome sequencing (WES). Initial and follow-up examination of color fundus photos after 10 years revealed an increase in bone spicule pigment deposits in both eyes. A parafoveal hyper-AF ring in both eyes was shown in fundus autofluorescence (FAF) with a progressive diameter-wise constriction observed over 8 years. Outer nuclear layer (ONL) loss was observed in parafoveal and perifoveal regions of both eyes on spectral domain-optical coherence tomography (SD-OCT). Full-field electroretinography (ffERG) showed extinguished global retinal function. WES identified a novel two-base-pair deletion, c.60_61del (p.Phe21Ter), in the PCDH15 gene, confirming the diagnosis of USH1F. CONCLUSIONS: We report a novel homozygous PCDH15 pathogenic variant expected to lead to nonsense-mediated decay (NMD) of PCDH15 mRNA. The patient exhibits a loss of function with USH1F, experiencing congenital hearing loss and syndromic RP.

Albumin use for fluid resuscitation in cardiac surgical patients: a survey of Canadian perioperative care providers.

PURPOSE: To evaluate the perceptions and practices of Canadian cardiovascular anesthesiologists and intensivists towards intravenous albumin as a resuscitation fluid in patients undergoing cardiac surgery. METHODS: We conducted a cross-sectional survey of cardiac anesthesiologists and intensivists involved in the care of cardiac surgical patients. The 22-item survey included seven open-ended questions and assessed practice patterns and attitudes towards albumin. Descriptive statistics were analyzed using counts and proportions. Qualitative data were analyzed to identify themes describing albumin use patterns in Canada. RESULTS: A total of 133 respondents from seven provinces participated, with 83 (62%) using albumin perioperatively. The majority of respondents (77%) felt a low fluid balance in cardiac surgical patients was important, and that supplementing crystalloids with albumin was helpful for this objective (67%). There was poor agreement among survey respondents regarding the role of albumin for faster vasopressor weaning or intensive care discharge, and ≥ 90% did not feel albumin reduced mortality, renal injury, or coagulopathy. Nevertheless, cardiac surgical patients were identified as a distinct population where albumin may help to minimize fluid balance. There was an acknowledged paucity of formal evidence supporting possible benefits. Fewer than 10% of respondents could identify institutional or national guidelines for albumin use. A lack of evidence supporting albumin use in cardiac surgical patients, especially those at highest risk of complications, was a frequently identified concern. CONCLUSIONS: The majority of Canadian anesthesiologists and intensivists (62%) use albumin in cardiac surgical patients. There is clinical equipoise regarding its utility, and an acknowledged need for higher quality evidence to guide practice.

RéSUMé: OBJECTIF: Évaluer les perceptions et les pratiques des anesthésiologistes et intensivistes cardiovasculaires canadiens à l'égard de l'albumine intraveineuse comme liquide de réanimation pour les patients bénéficiant d'une chirurgie cardiaque. MéTHODE: Nous avons mené un sondage transversal auprès d'anesthésiologistes et d'intensivistes cardiaques impliqués dans les soins aux patients de chirurgie cardiaque. Le sondage en 22 éléments comprenait sept questions ouvertes et évaluait les habitudes de pratique et les attitudes des praticiens à l'égard de l'albumine. Les statistiques descriptives ont été analysées à l'aide de dénombrements et de proportions. Des données qualitatives ont été analysées pour identifier des thèmes décrivant les tendances d'utilisation de l'albumine au Canada. RéSULTATS: Au total, 133 répondants de sept provinces ont participé, et 83 (62 %) utilisent l'albumine en périopératoire. La majorité des répondants (77 %) estimaient qu'un bilan liquidien négatif était important chez les patients en chirurgie cardiaque et que la supplémentation en cristalloïdes par de l'albumine était utile pour atteindre cet objectif (67 %). Il y avait un faible accord parmi les répondants concernant le rôle de l'albumine pour accélérer le sevrage des vasopresseurs ou la sortie de soins intensifs, et ≥ 90 % ne pensaient pas que l'albumine réduisait la mortalité, les lésions rénales ou la coagulopathie. Néanmoins, les patients en chirurgie cardiaque ont été identifiés comme une population distincte pour laquelle l'albumine pourrait contribuer à minimiser le bilan liquidien. Il y avait un manque reconnu de données probantes formelles à l'appui des avantages possibles. Moins de 10 % des répondants ont pu trouver des lignes directrices institutionnelles ou nationales portant sur l'utilisation de l'albumine. Le manque de données probantes à l'appui de l'utilisation de l'albumine chez les patients en chirurgie cardiaque, en particulier chez ceux présentant le risque le plus élevé de complications, était une préoccupation fréquemment identifiée. CONCLUSION: La majorité des anesthésiologistes et intensivistes canadiens (62 %) utilisent l'albumine chez les patients en chirurgie cardiaque. Il existe un équilibre clinique quant à son utilité et un besoin reconnu de données probantes de meilleure qualité pour guider la pratique.

Effects of TIMP-2 Polymorphisms on Retinopathy of Prematurity Risk, Severity, Recurrence, and Treatment Response.

Tissue inhibitors of metalloproteinases (TIMPs) play a crucial role in endogenous angiogenesis besides the regulation of matrix metalloproteinase (MMP) activity. Associations between TIMP-2 gene polymorphisms and the risk of retinopathy of prematurity (ROP) were examined. Premature infants born between 2009 and 2018 were included. Five single-nucleotide polymorphisms (SNPs) of TIMP-2 were analyzed with real-time polymerase chain reaction (PCR). Multivariate logistic regression was applied to model associations between TIMP-2 polymorphisms and ROP susceptibility and severity. The GA+AA genotype in individuals with the TIMP-2 polymorphism of rs12600817 was associated with a higher risk of ROP (odds ratio [OR]: 1.518, 95% confidence interval [CI]: 1.028-2.242) compared with their wild-type genotypes. The AA genotype (OR: 1.962, 95% CI: 1.023-3.762) and the AA+GA genotype (OR: 1.686, 95% CI: 1.030-2.762) in individuals with the rs12600817 polymorphism had higher risks of severe, treatment-requiring ROP relative to their wild-type counterparts. In patients with treatment-requiring ROP, the AG+GG genotypes in the TIMP-2 polymorphism of rs2889529 were correlated with the treatment response (p = 0.035). The TIMP-2 polymorphism of rs12600817 help in predicting ROP risks in preterm infants, while the polymorphism of rs2889529 can serve as a genetic marker in evaluating the ROP treatment response.

Congenital Stationary Night Blindness: Clinical and Genetic Features.

Congenital stationary night blindness (CSNB) is an inherited retinal disease (IRD) that causes night blindness in childhood with heterogeneous genetic, electrophysical, and clinical characteristics. The development of sequencing technologies and gene therapy have increased the ease and urgency of diagnosing IRDs. This study describes seven Taiwanese patients from six unrelated families examined at a tertiary referral center, diagnosed with CSNB, and confirmed by genetic testing. Complete ophthalmic exams included best corrected visual acuity, retinal imaging, and an electroretinogram. The effects of identified novel variants were predicted using clinical details, protein prediction tools, and conservation scores. One patient had an autosomal dominant CSNB with a RHO variant; five patients had complete CSNB with variants in GRM6, TRPM1, and NYX; and one patient had incomplete CSNB with variants in CACNA1F. The patients had Riggs and Schubert-Bornschein types of CSNB with autosomal dominant, autosomal recessive, and X-linked inheritance patterns. This is the first report of CSNB patients in Taiwan with confirmed genetic testing, providing novel perspectives on molecular etiology and genotype-phenotype correlation of CSNB. Particularly, variants in TRPM1, NYX, and CACNA1F in our patient cohort have not previously been described, although their clinical significance needs further study. Additional study is needed for the genotype-phenotype correlation of different mutations causing CSNB. In addition to genetic etiology, the future of gene therapy for CSNB patients is reviewed and discussed.

Role of growth factors and internal limiting membrane constituents in müller cell migration.

This study investigated the effects of growth factors and internal limiting membrane components on Müller cell migration. We studied the effects of epidermal growth factor (EGF), fibroblast growth factor (FGF), somatomedin (IGF-1), platelet derived growth factor (PDGF), and stromal cell-derived factor-1 alpha (SDF-1α) as well as collagen IV, laminin, and fibronectin on the proliferative and migratory activities of rat Müller cells in vitro. A water soluble tetrazolium-1 assay was used to quantify the viability of Müller cells in respective cultures, and analysis was performed using an enzyme-linked immunosorbent assay reader. All the factors examined had significant proliferative effects on cultured Müller cells (p < .05). A two-well Ibidi silicone culture insert was used to assess Müller cell migration. Müller cells cultured in EGF, FGF, IGF-1, collagen IV, and laminin but not in SDF, PDGF, or fibronectin effectively increased the cell migratory activity (p < .001). In addition, combined EGF and collagen IV, combined FGF and collagen IV, and combined IGF-1 and laminin exhibited more significant (p < .001) effects on Müller cell migration compared with culture a single factor. In summary, this study revealed the combinatorial effects of various growth factors and individual internal limiting membrane constituents. This may assist Müller cell migration together with the macular hole healing process.

Factors associated with virtual care access in older adults: a cross-sectional study.

BACKGROUND: virtual care has been critical during the COVID-19 pandemic, but there may be inequities in accessing different virtual modalities (i.e. telephone or videoconference). OBJECTIVE: to describe patient-specific factors associated with receiving different virtual care modalities. DESIGN: cross-sectional study. SETTING AND SUBJECTS: we reviewed medical records of all patients assessed virtually in the geriatric medicine clinic at St. Michael's Hospital, Toronto, Canada, between 17 March and 13 July 2020. METHODS: we derived adjusted odds ratios (OR), risk differences (RDs) and marginal and predicted probabilities, with 95% confidence intervals, from a multivariable logistic regression model, which tested the association between having a videoconference assessment (vs. telephone) and patient age, sex, computer ability, education, frailty (Clinical Frailty Scale score), history of cognitive impairment and immigration history; language of assessment and caregiver involvement in assessment. RESULTS: our study included 330 patients (227 telephone and 103 videoconference assessments). The median population age was 83 (Q1-Q3, 76-88) and 45.2% were male. Frailty (adjusted OR 0.62, 0.45-0.85; adjusted RD -0.08, -0.09 to -0.06) and absence of a caregiver (adjusted OR 0.12, 0.06-0.24; adjusted RD -0.35, -0.43 to -0.26) were associated with lower odds of videoconference assessment. Only 32 of 98 (32.7%) patients who independently use a computer participated in videoconference assessments. CONCLUSIONS: older adults who are frail or lack a caregiver to attend assessments with them may not have equitable access to videoconference-based virtual care. Future research should evaluate interventions that support older adults in accessing videoconference assessments.

PGC-1 coactivators regulate MITF and the tanning response.

The production of pigment by melanocytes tans the skin and protects against skin cancers. UV-exposed keratinocytes secrete α-MSH, which then activates melanin formation in melanocytes by inducing the microphthalmia-associated transcription factor (MITF). We show that PPAR-γ coactivator (PGC)-1α and PGC-1ß are critical components of this melanogenic system in melanocytes. α-MSH signaling strongly induces PGC-1α expression and stabilizes both PGC-1α and PGC-1ß proteins. The PGC-1s in turn activate the MITF promoter, and their expression correlates strongly with that of MITF in human melanoma cell lines and biopsy specimens. Inhibition of PGC-1α and PGC-1ß blocks the α-MSH-mediated induction of MITF and melanogenic genes. Conversely, overexpression of PGC-1α induces pigment formation in cell culture and transgenic animals. Finally, polymorphism studies reveal expression quantitative trait loci in the PGC-1ß gene that correlate with tanning ability and protection from melanoma in humans. These data identify PGC-1 coactivators as regulators of human tanning.

Predicting visual acuity in Bietti crystalline dystrophy: evaluation of image parameters.

BACKGROUND: To analyze multiple imaging modalities in patients with Bietti crystalline dystrophy (BCD) and to investigate which factors from these modalities are associated with best corrected visual acuity (BCVA). METHODS: In this retrospective study, 40 eyes from 22 patients with BCD were included and were separated into group 1 (BCVA ≤20/200) and group 2 (BCVA > 20/200). Data including BCVA and characteristic findings from near-infrared reflectance (NIR) imaging, fundus autofluorescence (FAF), and spectral domain-optic coherence tomography (SD-OCT) were analyzed and compared. The outcome measures of multimodal imaging were evaluated for correlation with BCVA. RESULTS: NIR is a good diagnostic tool for detecting either crystalline or sclerotic vessels in BCD. Patients in group 1 tended to have a thinner choroid (P = 0.047) with ellipsoid zone (EZ) disruption (P = 0.011). Calculation of the area under the curve indicated that EZ disruption detected on SD-OCT could be a good predictor of legal blindness in BCD. CONCLUSION: For the diagnosis of BCD, NIR could be a good diagnostic tool. Of the studied imaging modalities, we found that EZ disruption at the fovea were strongly associated with legal blindness, which could be easily assessed by SD-OCT.

Panel forecasts of country-level Covid-19 infections.

We use a dynamic panel data model to generate density forecasts for daily active Covid-19 infections for a panel of countries/regions. Our specification that assumes the growth rate of active infections can be represented by autoregressive fluctuations around a downward sloping deterministic trend function with a break. Our fully Bayesian approach allows us to flexibly estimate the cross-sectional distribution of slopes and then implicitly use this distribution as prior to construct Bayes forecasts for the individual time series. We find some evidence that information from locations with an early outbreak can sharpen forecast accuracy for late locations. There is generally a lot of uncertainty about the evolution of active infection, due to parameter and shock uncertainty, in particular before and around the peak of the infection path. Over a one-week horizon, the empirical coverage frequency of our interval forecasts is close to the nominal credible level. Weekly forecasts from our model are published at https://laurayuliu.com/covid19-panel-forecast/.

Baseline clinical features predict visual outcome in young patients with central retinal vein occlusion.

PURPOSE: To evaluate prognostic factors in young patients with central retinal vein occlusion (CRVO). METHODS: Retrospective case series. CRVO patients aged ≤ 50 and follow-up ≥ 6 months were enrolled. The best corrected visual acuity (BCVA) and central retinal thickness (CRT) at baseline, 3 months, 6 months, and last visit were documented. Severity of retinopathy was graded by comparing to standard photos. Prognostic factors associated with visual outcome at 6 months were evaluated by multiple linear regression models. RESULTS: A total of 73 eyes from 69 patients with mean age 37.6 ± 8.5 were enrolled. Forty-seven (68%) patients were male. The mean follow-up duration was 25.9 ± 23.0 months. LogMAR BCVA improved from 0.979 ± 0.785 at baseline to 0.594 ± 0.748 at the 6 months (p < 0.001) and CRT improved from 475 ± 222 µm to 299 ± 104 µm (p < 0.001). Forty-eight (66%) eyes required anti-vascular endothelial growth factor (anti-VEGF) treatment. The mean number of injections was 2.25 ± 1.41 in the first 6 months and 75% of eyes received ≦ 3 injections during the clinical course. The baseline BCVA (coefficient 0.518, p < 0.001), grade of retinal hemorrhage (coefficient 0.230, p = 0.006), grade of retinal venous engorgement (coefficient 0.238, p = 0.011), grade of optic disc edema (coefficient - 0.226, p = 0.005), and diabetes mellitus (coefficient 0.264, p = 0.047) were the independent factors associated with visual outcome at 6 months. CONCLUSIONS: Baseline clinical features are useful for the prediction of visual outcome at 6 months in young CRVO patients.

ANATOMICAL AND FUNCTIONAL RESULTS OF INTRAVITREAL AFLIBERCEPT MONOTHERAPY FOR TYPE 1 RETINOPATHY OF PREMATURITY: One-Year Outcomes.

PURPOSE: To evaluate the anatomical and functional outcomes of Type 1 retinopathy of prematurity 1 year after the intravitreal injection of aflibercept (IVA). METHODS: This prospective cohort study enrolled Type 1 retinopathy of prematurity patients who had been treated with IVA as first-line therapy from July 1, 2015, to June 30, 2017. Patients were followed up for at least 1 year after injection. The primary outcomes were retinopathy of prematurity regression, progression, reactivation, and the occurrence of associated complications after the use of IVA. The secondary outcomes were visual acuity and refractive error at 1 year after IVA. RESULTS: Seventeen eyes of nine patients were enrolled in our study. A single IVA injection resulted in resolution in 15 eyes (88.2%), whereas 2 eyes (11.8%) needed retreatment. The mean Snellen visual acuity and refractive error were 6/13 ± 0.34 and -1.94 ± 2.97 D, respectively. No major ocular complications or systemic adverse effects were noted during the follow-up period, except one patient (11%) passed away at the age of 14 months due to a pulmonary infection. CONCLUSION: Aflibercept is effective and well tolerated for the treatment of Type 1 retinopathy of prematurity; it is a potential treatment option as it achieves good anatomical, visual, and refractive outcomes.

FLUORESCEIN ANGIOGRAPHY FINDINGS IN UNILATERAL PERSISTENT FETAL VASCULATURE.

OBJECTIVE: This study aims to examine retinal vascular findings for affected eyes and contralateral eyes as well in typical cases of unilateral persistent fetal vasculature. METHODS: We retrospectively reviewed all patients evaluated at Chang Gung Memorial Hospital, Linkou, for unilateral persistent fetal vasculature between January 2008 and July 2017. All patients underwent fluorescein angiography (FA) examination under general anesthesia. FA was performed using RetCam 3 (Clarity Medical Systems, Inc, Pleasanton, CA). RESULTS: Ten patients (eight male and two female) were identified as having adequate clinical data for the final analysis. The mean age at diagnosis was 13.7 ± 17.2 months (range 1-58). The mean axial length was shorter in the affected eyes as compared to the fellow eyes (17.27 ± 2.8 vs. 20.2 ± 1.7 mm; P = 0.024). In the affected eyes, nine cases (90.0%) showed a concomitant retrolental stalk, avascular peripheral retina, regional capillary dropout, and absence of foveal avascular zone. Hyperfluorescent stalk was seen in seven cases (70.0%). Four eyes (40.0%) showed leaking vessels. Terminal supernumerary branching was seen in two cases (20.0%). Popcorn hyperfluorescence was noted in one case (10.0%). In the fellow eyes, peripheral avascular zone was noted in nine eyes (90.0%), of which six (60.0%) had peripheral zones greater than two-disk diameters. Seven eyes (70.0%) presented with regional capillary dropout and abnormal choroidal filling. Three eyes (30.0%) had abnormal vessel straightening. Aberrant circumferential vessels and leaking spots were seen in two eyes (20.0%). Regional dilation of disk vessels, peripheral vessel dilation, and terminal bulbing were noted in one eye (10.0%). The mean best-corrected visual acuity of the fellow eyes was 20/39 (0.29 in logarithm of the minimum angle of resolution). CONCLUSION: Retinal vascular abnormalities in the affected eyes and fundoscopically normal fellow eyes of unilateral persistent fetal vasculature patients were found in 100% and 90.0% of patients, respectively. Fellow eyes had some subtle abnormalities that were only revealed through FA. These unilateral persistent fetal vasculature cases were still bilaterally affected.