Review on the Safety and Efficacy of Brolucizumab for Neovascular Age-Related Macular Degeneration From Major Studies and Real-World Data.

Frequent antivascular endothelial growth factor injections in neovascular age-related macular degeneration (nAMD) often lead to poor compliance and suboptimal outcomes. A longer-acting agent has been a pressing unmet need until recently. Brolucizumab, an antivascular endothelial growth factor agent, is a single-chain antibody fragment approved by the US Food and Drug Administration (FDA) on October 8, 2019, for treating nAMD. It delivers more molecules at equivalent volumes of aflibercept, thus achieving a longer-lasting effect. We reviewed literature published in English between January 2016 and October 2022 from MEDLINE, PubMed, Cochrane database, Embase, and Google scholar using the keywords: "Brolucizumab, real-world data, intraocular inflammation (IOI), safety, and efficacy". Brolucizumab showed reduced injection frequency, better anatomic outcomes, and noninferior vision gains compared with aflibercept in HAWK and HARRIER studies. However, post hoc studies on brolucizumab revealed a higher-than-expected incidence of IOI, leading to the early termination of 3 studies: MERLIN, RAPTOR, and RAVEN for nAMD, branch retinal vein occlusion, and central retinal vein occlusion, respectively. Contrastingly real-world data showed encouraging outcomes in terms of fewer IOI cases. The subsequent amendment of the treatment protocol resulted in reduced IOI. Thereafter US FDA approved its use in diabetic macular edema on June 1, 2022. Based on major studies and real-world data, this review shows that brolucizumab is effective for treating naive and refractory nAMD. The risk of IOI is acceptable and manageable, but proper preinjection screening and high-vigilance care of IOI are needed. More studies are warranted to evaluate further the incidence, best prevention, and treatment measures for IOI.

Update on Current Microbiological Techniques for Pathogen Identification in Infectious Endophthalmitis.

Infectious endophthalmitis is a vision-threatening medical emergency that requires prompt clinical diagnosis and the initiation of treatment. However, achieving precision in endophthalmitis management remains challenging. In this review, we provide an updated overview of recent studies that are representative of the current trends in clinical microbiological techniques for infectious endophthalmitis.

Use of OCT Angiography to Diagnose and Manage Atypical Presentations of Macular Telangiectasia Type 2.

Macular telangiectasia Type 2 (MacTel) is a bilateral acquired retinal disease characterized by both vascular changes and atrophy of the retina. The purpose of this case series is to highlight the use of optical coherence tomography angiography (OCTA) as a non-invasive imaging modality to distinguish atypical MacTel from other macular conditions with similar presentations. We performed a retrospective review of patients referred to our academic retinal practice with unconfirmed or misdiagnosed MacTel between July 2017 and July 2021. Patients' OCTA imaging findings were reviewed to guide the appropriate diagnosis and management of atypical MacTel. Fifteen eyes from eight patients were included in this study. Six patients were referred with previous diagnoses of either full-thickness macular hole, lamellar hole, vitreomacular traction (VMT), postoperative cystoid macular edema (CME), or diabetic macular edema (DME). Two patients were referred to us to confirm the diagnosis of MacTel. OCTA revealed telangiectatic vessels in the temporal parafovea of all 15 eyes. OCTA also highlighted previously undiagnosed subretinal neovascularization (SRNV) in seven eyes. OCTA imaging is a valuable imaging modality to distinguish MacTel from other macular conditions, whose treatment courses vary substantially. Due to its ease of use, it holds immense potential in the future as treatments for non-proliferative MacTel emerge.

Ocular Injuries From Drive-by Paintball Shootings.

PURPOSE: To characterize ocular injuries from drive-by paintball shootings with a focus on the severity of injuries sustained, clinical management, and visual outcomes. DESIGN: Retrospective, interventional case series. METHODS: Setting: University practice and emergency department. PATIENT POPULATION: Patients evaluated by the ophthalmology service for paintball injuries. OBSERVATION PROCEDURE: Age, sex, eye laterality, mechanism of injury, initial best-corrected visual acuity (BCVA), and initial diagnosis. MAIN OUTCOME MEASURES: Clinical intervention(s), BCVA at last follow-up visit, and severity of injuries with a focus on ruptured globes. RESULTS: Twenty patients suffered unilateral ocular injuries from drive-by paintball shootings between January 2020 and December 2021. The median follow-up interval was 7.1 weeks (range: 3 days to 11.4 months). The average patient age at presentation was 36.6 years (range: 13-64 years). Fourteen patients (70%) had an initial BCVA of counting fingers or worse. Six patients (30%) suffered a ruptured globe injury requiring surgical repair, of whom 3 (15%) underwent subsequent evisceration. Twelve patients (60%) suffered ocular injuries requiring surgical intervention. Fifteen ocular surgeries were performed on 9 patients (45%) at our institution with 3 patients referred to outside providers for definitive surgical management due to insurance. BCVA at last follow-up visit was no light perception in 5 patients. CONCLUSIONS: The severity of injury after paintball-induced ocular trauma is higher in this case series than what has previously been reported in the literature. Paintball guns can cause devastating ocular injury when used as an assault weapon, and their use in unregulated settings bears further scrutiny.

Metformin and retinal diseases in preclinical and clinical studies: Insights and review of literature.

Metformin is one of the most prescribed drugs in the world giving potential health benefits beyond that of type 2 diabetes (T2DM). Emerging evidence suggests that it may have protective effects for retinal/posterior segment diseases including diabetic retinopathy (DR), age-related macular degeneration (AMD), inherited retinal degeneration such as retinitis pigmentosa (RP), primary open angle glaucoma (POAG), retinal vein occlusion (RVO), and uveitis. Metformin exerts potent anti-inflammatory, antiangiogenic, and antioxidative effects on the retina in response to pathologic stressors. In this review, we highlight the broad mechanism of action of metformin through key preclinical studies on animal models and cell lines used to simulate human retinal disease. We then explore the sparse but promising retrospective clinical data on metformin's potential protective role in DR, AMD, POAG, and uveitis. Prospective clinical data is needed to clarify metformin's role in management of posterior segment disorders. However, given metformin's proven broad biochemical effects, favorable safety profile, relatively low cost, and promising data to date, it may represent a new therapeutic preventive and strategy for retinal diseases.

Characterization of 475 Novel, Putative Small RNAs (sRNAs) in Carbon-Starved Salmonella enterica Serovar Typhimurium.

An increasingly apparent role of noncoding RNA (ncRNAs) is to coordinate gene expression during environmental stress. A mounting body of evidence implicates small RNAs (sRNAs) as key drivers of Salmonella stress survival. Generally thought to be 50-500 nucleotides in length and to occur in intergenic regions, sRNAs typically regulate protein expression through base pairing with mRNA targets. In this work, through employing a refined definition of sRNAs allowing for shorter sequences and sRNA loci to overlap with annotated protein-coding gene loci, we have identified 475 previously unannotated sRNAs that are significantly differentially expressed during carbon starvation (C-starvation). Northern blotting and quantitative RT-PCRs confirm the expressions and identities of several of these novel sRNAs, and our computational analyses find the majority to be highly conserved and structurally related to known sRNAs. Importantly, we show that deletion of one of the sRNAs dynamically expressed during C-starvation, sRNA4130247, significantly impairs the Salmonella C-starvation response (CSR), confirming its involvement in the Salmonella CSR. In conclusion, the work presented here provides the first-ever characterization of intragenic sRNAs in Salmonella, experimentally confirms that sRNAs dynamically expressed during the CSR are directly involved in stress survival, and more than doubles the Salmonella enterica sRNAs described to date.

Characterization of novel small RNAs (sRNAs) contributing to the desiccation response of Salmonella enterica serovar Typhimurium.

Noncoding RNA (ncRNA) modulation of gene expression has now been ubiquitously observed across all domains of life. An increasingly apparent role of ncRNAs is to coordinate changes in gene expressions in response to environmental stress. Salmonella enterica, a common food-born pathogen, is known for its striking ability to survive, adapt, and thrive in various unfavourable environments which makes it a particularly difficult pathogen to eliminate as well as an interesting model in which to study ncRNA contributions to cellular stress response. Mounting evidence now suggests that small RNAs (sRNAs) represent key regulators of Salmonella stress adaptation. Approximately 50-500 nucleotides in length, sRNAs regulate gene expression through complementary base pairing with molecular targets and have recently been suggested to outnumber protein-coding genes in bacteria. In this work, we employ small RNA transcriptome sequencing to characterize changes in the sRNA profiles of Salmonella in response to desiccation. In all, we identify 102 previously annotated sRNAs significantly differentially expressed during desiccation; and excitingly, 71 novel sRNAs likewise differentially expressed. Small transcript northern blotting and qRT-PCRs confirm the identities and expressions of several of our novel sRNAs, and computational analyses indicate the majority are highly conserved and structurally related to characterized sRNAs. Predicted sRNA targets include several proteins necessary for desiccation survival and this, in part, suggests a role for desiccation-regulated sRNAs in this stress response. Furthermore, we find individual knock-outs of two of the novel sRNAs identified herein, either sRNA1320429 or sRNA3981754, significantly impairs the ability of Salmonella to survive desiccation, confirming their involvements (and suggesting the potential involvements of other sRNAs we identify in this work) in the Salmonella response to desiccation.

ADAR Mediated RNA Editing Modulates MicroRNA Targeting in Human Breast Cancer.

RNA editing by RNA specific adenosine deaminase acting on RNA (ADAR) is increasingly being found to alter microRNA (miRNA) regulation. Editing of miRNA transcripts can affect their processing, as well as which messenger RNAs (mRNAs) they target. Further, editing of target mRNAs can also affect their complementarity to miRNAs. Notably, ADAR editing is often increased in malignancy with the effect of these RNA changes being largely unclear. In addition, numerous reports have now identified an array of miRNAs that directly contribute to various malignancies although the majority of their targets remain largely undefined. Here we propose that modulating the targets of miRNAs via mRNA editing is a frequent occurrence in cancer and an underappreciated participant in pathology. In order to more accurately characterize the relationship between these two regulatory processes, this study examined RNA editing events within mRNA sequences of two breast cancer cell lines (MCF-7 and MDA-MB-231) and determined whether or not these edits could modulate miRNA associations. Computational analyses of RNA-Seq data from these two cell lines identified over 50,000 recurrent editing sites within human mRNAs, and many of these were located in 3' untranslated regions (UTRs). When these locations were screened against the list of currently-annotated miRNAs we discovered that editing caused a subset (~9%) to have significant alterations to mRNA complementarity. One miRNA in particular, miR-140-3p, is known to be misexpressed in many breast cancers, and we found that mRNA editing allowed this miRNA to directly target the apoptosis inducing gene DFFA in MCF-7, but not in MDA-MB-231 cells. As these two cell lines are known to have distinct characteristics in terms of morphology, invasiveness and physiological responses, we hypothesized that the differential RNA editing of DFFA in these two cell lines could contribute to their phenotypic differences. Indeed, we confirmed through western blotting that inhibiting miR-140-3p increases expression of the DFFA protein product in MCF-7, but not MDA-MB-231, and further that inhibition of miR-140-3p also increases cellular growth in MCF-7, but not MDA-MB-231. Broadly, these results suggest that the creation of miRNA targets may be an underappreciated function of ADAR and may help further elucidate the role of RNA editing in tumor pathogenicity.

Novel small RNA (sRNA) landscape of the starvation-stress response transcriptome of Salmonella enterica serovar typhimurium.

Small RNAs (sRNAs) are short (∼50-200 nucleotides) noncoding RNAs that regulate cellular activities across bacteria. Salmonella enterica starved of a carbon-energy (C) source experience a host of genetic and physiological changes broadly referred to as the starvation-stress response (SSR). In an attempt to identify novel sRNAs contributing to SSR control, we grew log-phase, 5-h C-starved and 24-h C-starved cultures of the virulent Salmonella enterica subspecies enterica serovar Typhimurium strain SL1344 and comprehensively sequenced their small RNA transcriptomes. Strikingly, after employing a novel strategy for sRNA discovery based on identifying dynamic transcripts arising from "gene-empty" regions, we identify 58 wholly undescribed Salmonella sRNA genes potentially regulating SSR averaging an ∼1,000-fold change in expression between log-phase and C-starved cells. Importantly, the expressions of individual sRNA loci were confirmed by both comprehensive transcriptome analyses and northern blotting of select candidates. Of note, we find 43 candidate sRNAs share significant sequence identity to characterized sRNAs in other bacteria, and ∼70% of our sRNAs likely assume characteristic sRNA structural conformations. In addition, we find 53 of our 58 candidate sRNAs either overlap neighboring mRNA loci or share significant sequence complementarity to mRNAs transcribed elsewhere in the SL1344 genome strongly suggesting they regulate the expression of transcripts via antisense base-pairing. Finally, in addition to this work resulting in the identification of 58 entirely novel Salmonella enterica genes likely participating in the SSR, we also find evidence suggesting that sRNAs are significantly more prevalent than currently appreciated and that Salmonella sRNAs may actually number in the thousands.