Postoperative Macular Proliferative Vitreoretinopathy: A Case Series and Literature Review

Premacular membranes developing following pars plana vitrectomy (PPV) can cause significant anatomical and functional deficits to the macula. Recent reports showed that postoperative premacular membranes are a localized presentation of macular proliferative vitreoretinopathy (mPVR). Here, we report retrospectively a case series of 5 patients with severe mPVR which developed following uneventful PPV and were followed up to 32 months in the Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, between October 2016 and February 2020. All patients underwent primary repair of rhegmatogenous retinal detachment (RRD) before mPVR developed. Mean best-corrected visual acuity (BCVA) at presentation was 20/76 Snellen (0.58 LogMAR). Median duration of the retinal detachment time until surgery was 1.5 days (range 1–21 days). Mean interval time from last normal follow-up exam to diagnosis of mPVR was 19 days (range 10–28). BCVA dropped from a mean of 20/38 Snellen (0.28 LogMAR) prior to mPVR development to 20/166 Snellen (0.92 LogMAR) following its development, recovering to 20/57 Snellen (0.45 LogMAR) after peeling of membranes. Mean central macular thickness measured by optical coherence tomography decreased from 711 to 354 μm postsurgery. In conclusion, short-term mPVR is a different entity from macular pucker in terms of rapid development, structural distortion, and visual compromise. Surgical treatment significantly restores macular function and anatomy

The tetraplex (CGG)n destabilizing proteins hnRNP A2 and CBF-A enhance the in vivo translation of fragile X premutation mRNA

Expansion of a (CGG)n sequence in the 5′-UTR of the FMR1 gene to >200–2000 repeats abolishes its transcription and initiates fragile X syndrome (FXS). By contrast, levels of FMR1 mRNA are 5–10-fold higher in FXS premutation carriers of >55–200 repeats than in normal subjects. Lack of a corresponding increase in the amount of the product FMRP protein in carrier cells suggest that (CGG)>55–200 tracts thwart translation. Here we report that a (CGG)99 sequence positioned upstream to reporter firefly (FL) gene selectively diminished mRNA translation in coupled and separate T7 promoter-driven in vitro transcription and translation systems. The (CGG)99 tract similarly depressed mRNA utilization in HEK293 human cells transfected with plasmids bearing FMR1 promoter-driven FL gene. A (CGG)33 RNA tract formed a largely RNase T1-resistant intramolecular secondary structure in the presence of K+ ions. Expression of the quadruplex (CGG)n disrupting proteins hnRNP A2 or CBF-A in HEK293 cells significantly elevated the efficacy of (CGG)99 FL mRNA translation whereas hnRNP A2 or CBF-A mutants lacking quadruplex (CGG)n disrupting activity did not. Taken together, our results suggest that secondary structures of (CGG)n in mRNA obstruct its translation and that quadruplex-disrupting proteins alleviate the translational block

KCNV2-associated retinopathy: genotype–phenotype correlations – KCNV2 study group report 3

BACKGROUND/AIMS: To investigate genotype–phenotype associations in patients withKCNV2retinopathy. METHODS: Review of clinical notes, best-corrected visual acuity (BCVA), molecular variants, electroretinography (ERG) and retinal imaging. Subjects were grouped according to the combination ofKCNV2variants—two loss-of-function (TLOF), two missense (TM) or one of each (MLOF)—and parameters were compared. RESULTS: Ninety-two patients were included. The mean age of onset (mean±SD) in TLOF (n=55), TM (n=23) and MLOF (n=14) groups was 3.51±0.58, 4.07±2.76 and 5.54±3.38 years, respectively. The mean LogMAR BCVA (±SD) at baseline in TLOF, TM and MLOF groups was 0.89±0.25, 0.67±0.38 and 0.81±0.35 for right, and 0.88±0.26, 0.69±0.33 and 0.78±0.33 for left eyes, respectively. The difference in BCVA between groups at baseline was significant in right (p=0.03) and left eyes (p=0.035). Mean outer nuclear layer thickness (±SD) at baseline in TLOF, MLOF and TM groups was 37.07±15.20 µm, 40.67±12.53 and 40.38±18.67, respectively, which was not significantly different (p=0.85). The mean ellipsoid zone width (EZW) loss (±SD) was 2051 µm (±1318) for patients in the TLOF, and 1314 µm (±965) for MLOF. Only one patient in the TM group had EZW loss at presentation. There was considerable overlap in ERG findings, although the largest DA 10 ERG b-waves were associated with TLOF and the smallest with TM variants. CONCLUSIONS: Patients with missense alterations had better BCVA and greater structural integrity. This is important for patient prognostication and counselling, as well as stratification for future gene therapy trials

Destabilization of tetraplex structures of the fragile X repeat sequence (CGG)(n) is mediated by homolog-conserved domains in three members of the hnRNP family

Hairpin or tetrahelical structures formed by a d(CGG)(n) sequence in the FMR1 gene are thought to promote expansion of the repeat tract. Subsequent to this expansion FMR1 is silenced and fragile X syndrome ensues. The injurious effects of d(CGG)(n) secondary structures may potentially be countered by agents that act to decrease their stability. We showed previously that the hnRNP-related protein CBF-A destabilized G′2 bimolecular tetraplex structures of d(CGG)(n). Analysis of mutant proteins revealed that the CBF-A-conserved domains RNP1(1) and ATP/GTP binding box were sufficient and necessary for G′2 d(CGG)(n) disruption while the RNP2(1) motif inhibited the destabilization activity. Here, we report that a C-terminal fragment of CBF-A whose only remaining conserved domain was the ATP/GTP binding motif, disrupted G′2 d(CGG)(n) more selectively than wild-type CBF-A. Further, two additional members of the hnRNP family, hnRNP A2 and mutant hnRNP A1 effectively destabilized G′2 d(CGG)(n). Examination of mutant hnRNP A2 proteins revealed that, similar to CBF-A, their RNP1(1) element and ATP/GTP binding motif mediated G′2 d(CGG)(n) disruption, while the RNP2(1) element blocked their action. Similarly, the RNP1(1) and RNP2(1) domains of hnRNP A1 were, respectively, positive and negative mediators of G′2 d(CGG)(n) destabilization. Last, employing the same conserved motifs that mediated disruption of the DNA tetraplex G′2 d(CGG)(n), hnRNP A2 destabilized r(CGG)(n) RNA tetraplex

Docking interactions of the JNK scaffold protein WDR62

JNK (c-Jun N-terminal kinase) is part of a MAPK (mitogen-activated protein kinase) signalling cascade. Scaffold proteins simultaneously associate with various components of the MAPK signalling pathway and play a crucial role in signal transmission and MAPK regulation. WDR62 (WD repeat domain 62) is a JNK scaffold protein. Recessive mutations within WDR62 result in severe cerebral cortical malformation. In the present study we demonstrate the association of WDR62 with endogenous and overexpressed proteins of both JNK2 and the JNK2-activating kinase MKK7 (MAPK kinase 7). Association of WDR62 with JNK2 and MKK7 occurs via direct protein–protein interactions. We mapped the docking domain of WDR62 responsible for the association with JNK. WDR62 interacts with all JNK isoforms through a D domain motif located at the C-terminus. A WDR62 mutant lacking the putative JNK-binding domain fails to activate and recruit JNK to cellular granules. Furthermore, a synthetic peptide composed of the WDR62 docking domain inhibits JNK2 activity in vitro. WDR62 association with JNK2 requires both the JNK CD and ED domains, and the binding requisite is distinct from that of the previously described JNK2 association with JIP1 (JNK-interacting protein 1). Next, we characterized the association between WDR62 and MKK7. WDR62 associates directly with the MKK7β1 isoform independently of JNK binding, but fails to interact with MKK7α1. Furthermore, MKK7β1 recruits a protein phosphatase that dephosphorylates WDR62. Interestingly, a premature termination mutation in WDR62 that results in severe brain developmental defects does not abrogate WDR62 association with either JNK or MKK7. Therefore such mutations represent a loss of WDR62 function independent of JNK signalling

Disease quiescence in endophthalmitis patients treated with anti-VEGF injections for retinal pathologies

Abstract Background The most feared complication of intravitreal injections is the development of endophthalmitis, which could lead to irreversible visual loss. The aim of this study was to characterize the clinical profiles, causative pathogens, and clinical outcome of patients post-endophthalmitis. Methods Retrospective, single center case series study. Clinical records, causative pathogens and management of all cases of endophthalmitis post intravitreal anti-vascular endothelial growth factor (VEGF) injections recorded between January 1st, 2006 and May 30th, 2022; were retrieved. The visual and anatomic changes prior to the episode of endophthalmitis and up to 2 years post-treatment were compared. Results Eleven post-injection endophthalmitis eyes of 10 patients (n = 3 females; 30%) were recruited at mean age of 64.5 ± 20.4 years. The median last recorded BCVA, up to 3 months prior to the episode of endophthalmitis was 60 (Interquartile range (IQR) 55–75) ETDRS letters. Then, it dropped to 30 (IQR 0-57.5), 35 (IQR 0-52.5) and 35 (IQR 0-57.5) ETDRS letters at presentation, 6- and 12-months follow-up; respectively (p = 0.027, p = 0.017 and p = 0.012). However, at 24 months, the median BCVA returned to similar baseline values prior to the episode of endophthalmitis; BCVA 50 (IQR 0–60) ETDRS letters, p = 0.062. Interestingly, two eyes with neovascular age-related macular degeneration (NVAMD), 1 with myopic choroidal neovascularization (CNV) and 1 with retinal vein occlusion (RVO), experienced disease quiescence and did not require additional anti-VEGF injections up to 2 years of follow-up. Conclusion This study demonstrates long-term recovery of vision loss due to endophthalmitis post anti-VEGF injections, regained up to 2 years later. It also indicates that disease quiescence post endophthalmitis may not only occur in eyes treated for NVAMD, but also with myopic CNV and RVO

Translational Read-Through Drugs (TRIDs) Are Able to Restore Protein Expression and Ciliogenesis in Fibroblasts of Patients with Retinitis Pigmentosa Caused by a Premature Termination Codon in <i>FAM161A</i>

Ataluren and Gentamicin are translational readthrough drugs (TRIDs) that induce premature termination codon (PTC) readthrough, resulting in the production of full-length proteins that usually harbor a single missense substitution. FAM161A is a ciliary protein which is expressed in photoreceptors, and pathogenic variants in this gene cause retinitis pigmentosa (RP). Applying TRIDs on fibroblasts from RP patients due to PTC in the FAM161A (p.Arg523*) gene may uncover whether TRIDs can restore expression, localization and function of this protein. Fibroblasts from six patients and five age-matched controls were starved prior to treatment with ataluren or gentamicin, and later FAM161A expression, ciliogenesis and cilia length were analyzed. In contrast to control cells, fibroblasts of patients did not express the FAM161A protein, showed a lower percentage of ciliated cells and grew shorter cilia after starvation. Ataluren and Gentamicin treatment were able to restore FAM161A expression, localization and co-localization with α-tubulin. Ciliogenesis and cilia length were restored following Ataluren treatment almost up to a level which was observed in control cells. Gentamicin was less efficient in ciliogenesis compared to Ataluren. Our results provide a proof-of-concept that PTCs in FAM161A can be effectively suppressed by Ataluren or Gentamicin, resulting in a full-length functional protein

Unique combination of clinical features in a large cohort of 100 patients with retinitis pigmentosa caused by FAM161A mutations

Contains fulltext : 226169.pdf (publisher's version ) (Open Access

TRPM1 Mutations are the Most Common Cause of Autosomal Recessive Congenital Stationary Night Blindness (CSNB) in the Palestinian and Israeli Populations

International audiencePrecise genetic and phenotypic characterization of congenital stationary night blindness (CSNB) patients is needed for future therapeutic interventions. The aim of this study was to estimate the prevalence of CSNB in our populations and to study clinical and genetic aspects of the autosomal recessive (AR) form of CSNB. This is a retrospective cohort study of Palestinian and Israeli CSNB patients harboring mutations in TRPM1 underwent comprehensive ocular examination. Genetic analysis was performed using homozygosity mapping and sequencing. 161 patients (from 76 families) were recruited for this study, leading to a prevalence of 1:6210 in the vicinity of Jerusalem, much higher than the worldwide prevalence. 61% of the families were consanguineous with AR inheritance pattern. Biallelic pathogenic TRPM1 mutations were identified in 36 families (72 patients). Two founder mutations explain the vast majority of cases: a nonsense mutation c.880A>T (p.Lys294*) identified in 22 Palestinian families and a large genomic deletion (36,445 bp) encompassing exons 2–7 of TRPM1 present in 13 Ashkenazi Jewish families. Most patients were myopic (with mean BCVA of 0.40 LogMAR) and all had absent rod responses in full field electroretinography. To the best of our knowledge, this is the largest report of a clinical and genetic analysis of patients affected with CSNB due to TRPM1 mutations