Regulation of histone methylation by automethylation of PRC2.

Polycomb-repressive complex 2 (PRC2) is a histone methyltransferase that is critical for regulating transcriptional repression in mammals. Its catalytic subunit, EZH2, is responsible for the trimethylation of H3K27 and also undergoes automethylation. Using mass spectrometry analysis of recombinant human PRC2, we identified three methylated lysine residues (K510, K514, and K515) on a disordered but highly conserved loop of EZH2. Methylation of these lysines increases PRC2 histone methyltransferase activity, whereas their mutation decreases activity in vitro. De novo histone methylation in an EZH2 knockout cell line is greatly impeded by mutation of the automethylation lysines. EZH2 automethylation occurs intramolecularly (in cis) by methylation of a pseudosubstrate sequence on a flexible loop. This posttranslational modification and cis regulation of PRC2 are analogous to the activation of many protein kinases by autophosphorylation. We propose that EZH2 automethylation allows PRC2 to modulate its histone methyltransferase activity by sensing histone H3 tails, SAM concentration, and perhaps other effectors.

A sub-10-nm, folic acid-conjugated gold nanoparticle as self-therapeutic treatment of tubulointerstitial fibrosis.

Nanomedicines for treating chronic kidney disease (CKD) are on the horizon, yet their delivery to renal tubules where tubulointerstitial fibrosis occurs remains inefficient. We report a folic acid-conjugated gold nanoparticle that can transport into renal tubules and treat tubulointerstitial fibrosis in mice with unilateral ureteral obstruction. The 3-nm gold core allows for the dissection of bio-nano interactions in the fibrotic kidney, ensures the overall nanoparticle (~7 nm) to be small enough for glomerular filtration, and naturally inhibits the p38α mitogen-activated protein kinase in the absence of chemical or biological drugs. The folic acids support binding to selected tubule cells with overexpression of folate receptors and promote retention in the fibrotic kidney. Upon intravenous injection, this nanoparticle can selectively accumulate in the fibrotic kidney over the nonfibrotic contralateral kidney at ~3.6% of the injected dose. Delivery to the fibrotic kidney depends on nanoparticle size and disease stage. Notably, a single injection of this self-therapeutic nanoparticle reduces tissue degeneration, inhibits genes related to the extracellular matrix, and treats fibrosis more effectively than standard Captopril therapy. Our data underscore the importance of constructing CKD nanomedicines based on renal pathophysiology.

Interpreting the complexities of the plastid genome in dinoflagellates: a mini-review of recent advances.

Photosynthetic dinoflagellates play crucial roles in global primary production and carbon fixation. Despite their success in filling various ecological niches, numerous mysteries about their plastid evolution and plastid genomes remain unsolved. The plastid genome of dinoflagellates presents one of the most complex lineages in the biological realm, mainly due to multiple endosymbiotic plastid events in their evolutionary history. Peridinin-containing dinoflagellates possess the most reduced and fragmented genome, with only a few genes located on multiple "minicircles", whereas replacement plastids in dinoflagellate lineages have undergone different degrees of endosymbiotic gene transfer. Recent advancements in high-throughput sequencing have improved our understanding of plastid genomes and plastid-encoded gene expression in many dinoflagellate species. Plastid transcripts of dinoflagellates exhibit two unconventional processing pathways: the addition of a 3' poly(U) tail and substitutional RNA editing. These pathways are widely employed across dinoflagellate lineages, which are possibly retained from the ancestral peridinin plastid. This mini-review summarizes the developments in the plastid genomes of dinoflagellates and pinpoints the research areas that necessitate further exploration, aiming to provide valuable insights into plastid evolution in these fascinating and important organisms.

Nationally Automated Colonoscopy Performance Feedback Increases Polyp Detection: The NED APRIQOT Randomized Controlled Trial.

BACKGROUND & AIMS: Postcolonoscopy colorectal cancer incidence and mortality rates are higher for endoscopists with low polyp detection rates. Using the UK's National Endoscopy Database (NED), which automatically captures real-time data, we assessed if providing feedback of case-mix-adjusted mean number of polyps (aMNP), as a key performance indicator, improved endoscopists' performance. Feedback was delivered via a theory-informed, evidence-based audit and feedback intervention. METHODS: This multicenter, prospective, NED Automated Performance Reports to Improve Quality Outcomes Trial randomized National Health Service endoscopy centers to intervention or control. Intervention-arm endoscopists were e-mailed tailored monthly reports automatically generated within NED, informed by qualitative interviews and behavior change theory. The primary outcome was endoscopists' aMNP during the 9-month intervention. RESULTS: From November 2020 to July 2021, 541 endoscopists across 36 centers (19 intervention; 17 control) performed 54,770 procedures during the intervention, and 15,960 procedures during the 3-month postintervention period. Comparing the intervention arm with the control arm, endoscopists during the intervention period: aMNP was nonsignificantly higher (7%; 95% CI, -1% to 14%; P = .08). The unadjusted MNP (10%; 95% CI, 1%-20%) and polyp detection rate (10%; 95% CI, 4%-16%) were significantly higher. Differences were not maintained in the postintervention period. In the intervention arm, endoscopists accessing NED Automated Performance Reports to Improve Quality Outcomes Trial webpages had a higher aMNP than those who did not (aMNP, 118 vs 102; P = .03). CONCLUSIONS: Although our automated feedback intervention did not increase aMNP significantly in the intervention period, MNP and polyp detection rate did improve significantly. Engaged endoscopists benefited most and improvements were not maintained postintervention; future work should address engagement in feedback and consider the effectiveness of continuous feedback. CLINICAL TRIALS REGISTRY:  www.isrctn.org ISRCTN11126923 .

Evaluation of the international Ki67 working group cut point recommendations for early breast cancer: comparison with 21-gene assay results in a large integrated health care system.

PURPOSE: The International Ki67 Working Group (IKWG) has developed training for immunohistochemistry (IHC) scoring reproducibility and recommends cut points of ≤ 5% and ≥ 30% for prognosis in ER+, HER2-, stage I/II breast cancer. We examined scoring reproducibility following IKWG training and evaluated these cut points for selecting patients for further testing with the 21-gene Recurrence Score (RS) assay. METHODS: We included 307 women aged 50+ years with node-negative, ER+PR+HER2- breast cancer and with available RS results. Slides from the diagnostic biopsy were stained for Ki67 and scored using digital image analysis (IA). Two IHC pathologists underwent IKWG training and visually scored slides, blinded to each other and IA readings. Interobserver reproducibility was examined using intraclass correlation (ICC) and Kappa statistics. RESULTS: Depending on reader, 8.8-16.0% of our cohort had Ki67 ≤ 5% and 11.4-22.5% had scores ≥ 30%. The ICC for Ki67 scores by the two pathologists was 0.82 (95% CI 0.78-0.85); it was 0.79 (95% CI 0.74-0.83) for pathologist 1 and IA and 0.76 (95% CI 0.71-0.80) for pathologist 2 and IA. For Ki67 scores ≤ 5%, the percentages with RS < 26 were 92.6%, 91.8%, and 90.9% for pathologist 1, pathologist 2, and IA, respectively. For Ki67 scores ≥ 30%, the percentages with RS ≥ 26 were 41.5%, 51.4%, and 27.5%, respectively. CONCLUSION: The IKWG's Ki67 training resulted in moderate to strong reproducibility across readers but cut points had only moderate overlap with RS cut points, especially for Ki67 ≥ 30% and RS ≥ 26; thus, their clinical utility for a 21-gene assay testing pathway remains unclear.

Retinoblastoma has properties of a cone precursor tumor and depends upon cone-specific MDM2 signaling.

Retinoblastomas result from the inactivation of the RB1 gene and the loss of Rb protein, yet the cell type in which Rb suppresses retinoblastoma and the circuitry that underlies the need for Rb are undefined. Here, we show that retinoblastoma cells express markers of postmitotic cone precursors but not markers of other retinal cell types. We also demonstrate that human cone precursors prominently express MDM2 and N-Myc, that retinoblastoma cells require both of these proteins for proliferation and survival, and that MDM2 is needed to suppress ARF-induced apoptosis in cultured retinoblastoma cells. Interestingly, retinoblastoma cell MDM2 expression was regulated by the cone-specific RXRgamma transcription factor and a human-specific RXRgamma consensus binding site, and proliferation required RXRgamma, as well as the cone-specific thyroid hormone receptor-beta2. These findings provide support for a cone precursor origin of retinoblastoma and suggest that human cone-specific signaling circuitry sensitizes to the oncogenic effects of RB1 mutations.

Revealing the algicidal characteristics of Maribacter dokdonensis: An investigation into bacterial strain P4 isolated from Karenia mikimotoi bloom water.

Harmful algal blooms (HABs) are a global environmental concern, causing significant economic losses in fisheries and posing risks to human health. Algicidal bacteria have been suggested as a potential solution to control HABs, but their algicidal efficacy is influenced by various factors. This study aimed to characterize a novel algicidal bacterium, Maribacter dokdonensis (P4), isolated from a Karenia mikimotoi (Hong Kong strain, KMHK) HAB and assess the impact of P4 and KMHK's doses, growth phase, and algicidal mode and the axenicity of KMHK on P4's algicidal effect. Our results demonstrated that the algicidal effect of P4 was dose-dependent, with the highest efficacy at a dose of 25% v/v. The study also determined that P4's algicidal effect was indirect, with the P4 culture and the supernatant, but not the bacterial cells, showing significant effects. The algicidal efficacy was higher when both P4 and KMHK were in the stationary phase. Furthermore, the P4 culture at the log phase could effectively kill KMHK cells at the stationary phase, with higher algicidal efficacy in the bacterial culture than that of the supernatant alone. Interestingly, P4's algicidal efficacy was significantly higher when co-culturing with xenic KMHK (~90% efficacy at day 1) than that with the axenic KMHK (~50% efficacy at day 1), suggesting the presence of other bacteria could regulate P4's algicidal effect. The bacterial strain P4 also exhibited remarkable algicidal efficacy on four other dinoflagellate species, particularly the armored species. These results provide valuable insights into the algicidal effect of M. dokdonensis on K. mikimotoi and on their interactions.

Non-synonymous, synonymous, and non-coding nucleotide variants contribute to recurrently altered biological processes during retinoblastoma progression.

Retinoblastomas form in response to biallelic RB1 mutations or MYCN amplification and progress to more aggressive and therapy-resistant phenotypes through accumulation of secondary genomic changes. Progression-related changes include recurrent somatic copy number alterations and typically non-recurrent nucleotide variants, including synonymous and non-coding variants, whose significance has been unclear. To determine if nucleotide variants recurrently affect specific biological processes, we identified altered genes and over-represented variant gene ontologies in 168 exome or whole-genome-sequenced retinoblastomas and 12 tumor-matched cell lines. In addition to RB1 mutations, MYCN amplification, and established retinoblastoma somatic copy number alterations, the analyses revealed enrichment of variant genes related to diverse biological processes including histone monoubiquitination, mRNA processing (P) body assembly, and mitotic sister chromatid segregation and cytokinesis. Importantly, non-coding and synonymous variants increased the enrichment significance of each over-represented biological process term. To assess the effects of such mutations, we examined the consequences of a 3' UTR variant of PCGF3 (a BCOR-binding component of Polycomb repressive complex I), dual 3' UTR variants of CDC14B (a regulator of sister chromatid segregation), and a synonymous variant of DYNC1H1 (a regulator of P-body assembly). One PCGF3 and one of two CDC14B 3' UTR variants impaired gene expression whereas a base-edited DYNC1H1 synonymous variant altered protease sensitivity and stability. Retinoblastoma cell lines retained only ~50% of variants detected in tumors and enriched for new variants affecting p53 signaling. These findings reveal potentially important differences in retinoblastoma cell lines and tumors and implicate synonymous and non-coding variants, along with non-synonymous variants, in retinoblastoma oncogenesis.

Artificial Intelligence-Driven Morphology-Based Enrichment of Malignant Cells from Body Fluid.

Cell morphology is a fundamental feature used to evaluate patient specimens in pathologic analysis. However, traditional cytopathology analysis of patient effusion samples is limited by low tumor cell abundance coupled with the high background of nonmalignant cells, restricting the ability of downstream molecular and functional analyses to identify actionable therapeutic targets. We applied the Deepcell platform that combines microfluidic sorting, brightfield imaging, and real-time deep learning interpretations based on multidimensional morphology to enrich carcinoma cells from malignant effusions without cell staining or labels. Carcinoma cell enrichment was validated with whole genome sequencing and targeted mutation analysis, which showed a higher sensitivity for detection of tumor fractions and critical somatic variant mutations that were initially at low levels or undetectable in presort patient samples. Our study demonstrates the feasibility and added value of supplementing traditional morphology-based cytology with deep learning, multidimensional morphology analysis, and microfluidic sorting.

Full-field Scotopic Threshold Improvement after Voretigene Neparvovec-rzyl Treatment Correlates with Chorioretinal Atrophy.

PURPOSE: To analyze demographic and ophthalmic data in patients with and without chorioretinal atrophy after voretigene neparvovec-rzyl (VN) to identify possible causes for this phenomenon. DESIGN: Retrospective cohort study with longitudinal follow-up. PARTICIPANTS: A total of 71 eyes of 38 patients aged 2 to 44 years with RPE65-mediated retinal dystrophy treated with VN across 2 large gene therapy centers in the United States and Germany. METHODS: Patients treated with VN who developed atrophy were compared with those who did not. MAIN OUTCOME MEASURES: Gender, age, surgical center, spherical equivalent refraction, best-corrected visual acuity (BCVA), baseline full-field scotopic threshold testing (FST), and posttreatment change in FST. RESULTS: A total of 20 eyes of 12 patients developed atrophy after treatment with VN (28% of all eyes). There was no significant difference in gender, age, surgical center, or spherical equivalent refraction between the atrophy group and the no atrophy group. However, patients between school age and young adulthood were predominantly affected, whereas the youngest and the oldest patients did not develop atrophy. Baseline BCVA was better in patients who developed atrophy than those who did not (P = 0.006). The postoperative improvement in FST at 1 month was significantly higher in the atrophy group than in the no atrophy group (P = 0.0005), and this difference remained statistically significant at 1 year (P = 0.0001). There was no correlation to baseline FST, to inflammation, or to which eye was treated first. CONCLUSIONS: The degree of FST improvement after VN appears to be strongly correlated with the development of VN-related chorioretinal atrophy. This finding raises the possibility that atrophy may develop as a toxic or metabolic sequela of vector-mediated RPE65 expression. In light of the expanding number of retinal gene therapy clinical trials, this complication warrants further study because it may not be limited to VN. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

PyThinFilm: Automated Molecular Dynamics Simulation Protocols for the Generation of Thin Film Morphologies.

The performance of organic optoelectronic devices, such as organic light-emitting diodes (OLEDs) and organic solar cells (OSCs), is intrinsically related to the molecular-scale morphology of the thin films from which they are composed. However, the experimental characterization of morphology at the molecular level is challenging due to the often amorphous or at best semicrystalline nature of these films. Classical molecular modeling techniques, such as molecular dynamics (MD) simulation, are increasingly used to understand the relationship between morphology and the properties of thin-film devices. PyThinFilm (github.com/ATB-UQ/PyThinFilm) is an open-source Python package which allows fully automated MD simulations of thin film growth to be performed using vacuum and/or solution deposition processes. PyThinFilm utilizes the GROMACS simulation package in combination with interaction parameters from the Automated Topology Builder (atb.uq.edu.au). Here, PyThinFilm is described along with an overview of applications in which PyThinFilm has been used to study the thin films of organic semiconductor materials typically used in OLEDs and OSCs.

Effects of the multi-channeled oral irrigation (MCOI) unit in preventing dental plaque formation and gingivitis: A randomized controlled trial.

PURPOSE: To evaluate the efficacy of COMORAL a new multi-channeled oral irrigation (MCOI) unit with pulsating water jet, in plaque score reduction and gingivitis. METHODS: This was a single-blinded clinical randomized controlled trial (NCT05031260). Forty-two healthy subjects between 18 to 35 years old were initially recruited, and the control group (n = 20) and the intervention group (n = 17) were randomly assigned. Both groups were asked to brush their teeth one or two times a day without any supplementary oral hygiene products while the intervention group used COMORAL 3 times a day, 5 days a week. Clinical indices including gingival index (GI), plaque index (PI), bleeding on probing (BOP), pocket depth (PD), gingival recession (GR), and clinical attachment loss (CAL) were obtained at the baseline (D0), day 14 (D14), and day 28 (D28). Saliva was collected to examine the presence of periodontal pathogens. The repeated measures analysis of variance or generalized estimating equation was used to compare the interaction between groups and time points. The independent t-test or Mann-Whitney test were used for intergroup differences at each time point. RESULTS: At V0, PI, GI, BOP, and PD scores showed no differences between the two groups. At V1 and V2, these scores showed significant difference between two groups (P < 0.05) such that the intervention group showed gradual decreases while the control group showed no change. There were no differences in GR, CAL, and periodontal pathogens between the two groups. COMORAL showed improvement in reducing gingival inflammation and dental plaque formation adjuvant to routine toothbrushing in healthy adults. CLINICAL SIGNIFICANCE: The results of this study can be useful to clinicians when selecting oral hygiene devices that can help improve patients' routine oral hygiene practice and their overall oral health.

Upregulation of Peridinin-Chlorophyll A-Binding Protein in a Toxic Strain of Prorocentrum hoffmannianum under Normal and Phosphate-Depleted Conditions.

Some strains of the dinoflagellate species Prorocentrum hoffmannianum show contrasting ability to produce diarrhetic shellfish poisoning (DSP) toxins. We previously compared the okadaic acid (OA) production level between a highly toxic strain (CCMP2804) and a non-toxic strain (CCMP683) of P. hoffmannianum and revealed that the cellular concentration of OA in CCMP2804 would increase significantly under the depletion of phosphate. To understand the molecular mechanisms, here, we compared and analyzed the proteome changes of both strains growing under normal condition and at phosphate depletion using two-dimensional gel electrophoresis (2-DE). There were 41 and 33 differential protein spots observed under normal condition and phosphate depletion, respectively, of which most were upregulated in CCMP2804 and 22 were common to both conditions. Due to the lack of matched peptide mass fingerprints in the database, de novo peptide sequencing was applied to identify the differentially expressed proteins. Of those upregulated spots in CCMP2804, nearly 60% were identified as peridinin-chlorophyll a-binding protein (PCP), an important light-harvesting protein for photosynthesis in dinoflagellates. We postulated that the high expression of PCP encourages the production of DSP toxins by enhancing the yields of raw materials such as acetate, glycolate and glycine. Other possible mechanisms of toxicity related to PCP might be through triggering the transcription of non-ribosomal peptide synthetase/polyketide synthase genes and the transportation of dinophysistoxin-4 from chloroplast to vacuoles.

Society for Maternal-Fetal Medicine Special Statement: Best-practice recommendations for ultrasound network connectivity.

Prenatal ultrasound is an indispensable tool used by obstetrical care providers to assist in the everyday care of their pregnant patients. Alongside advancements in imaging, the electronic systems that support this technology have become more advanced. However, it is currently difficult for these individual systems to communicate with each other "out of the box." There is also minimal standardization of the type and format of data transmitted within these systems. Clinicians and system vendors must work collaboratively to create clinical and technical standards to serve as the foundation for increased interoperability among the various systems within each institutional network. Therefore, the Society for Maternal-Fetal Medicine Clinical Informatics Committee established an Ultrasound Electronic Health Record Subcommittee to facilitate collaboration between clinicians, including maternal-fetal medicine subspecialists, and ultrasound network component vendors. Based on the work of this subcommittee, the purpose of this document is to provide: (1) a basic understanding of ultrasound network architecture and capabilities, and (2) best-practice recommendations for electronic health record order design, obstetrical clinical data standards, and billing and coding practices.

Impact of the COVID-19 pandemic on UK endoscopic activity and cancer detection: a National Endoscopy Database Analysis.

OBJECTIVE: The COVID-19 pandemic has had a major global impact on endoscopic services. This reduced capacity, along with public reluctance to undergo endoscopy during the pandemic, might result in excess mortality from delayed cancer diagnosis. Using the UK's National Endoscopy Database (NED), we performed the first national analysis of the impact of the pandemic on endoscopy services and endoscopic cancer diagnosis. DESIGN: We developed a NED COVID-19 module incorporating procedure-level data on all endoscopic procedures. Three periods were designated: pre-COVID (6 January 2020 to 15 March), transition (16-22 March) and COVID-impacted (23 March-31 May). National, regional and procedure-specific analyses were performed. The average weekly number of cancers, proportion of missing cancers and cancer detection rates were calculated. RESULTS: A weekly average of 35 478 endoscopy procedures were performed in the pre-COVID period. Activity in the COVID-impacted period reduced to 12% of pre-COVID levels; at its low point, activity was only 5%, recovering to 20% of pre-COVID activity by study end. Although more selective vetting significantly increased the per-procedure cancer detection rate (pre-COVID 1.91%; COVID-impacted 6.61%; p<0.001), the weekly number of cancers detected decreased by 58%. The proportion of missing cancers ranged from 19% (pancreatobiliary) to 72% (colorectal). CONCLUSION: This national analysis demonstrates the remarkable impact that the pandemic has had on endoscopic services, which has resulted in a substantial and concerning reduction in cancer detection. Major, urgent efforts are required to restore endoscopy capacity to prevent an impending cancer healthcare crisis.

Proximity-based proteomics reveals the thylakoid lumen proteome in the cyanobacterium Synechococcus sp. PCC 7002.

Cyanobacteria possess unique intracellular organization. Many proteomic studies have examined different features of cyanobacteria to learn about the intracellular structures and their respective functions. While these studies have made great progress in understanding cyanobacterial physiology, the conventional fractionation methods used to purify cellular structures have limitations; specifically, certain regions of cells cannot be purified with existing fractionation methods. Proximity-based proteomics techniques were developed to overcome the limitations of biochemical fractionation for proteomics. Proximity-based proteomics relies on spatiotemporal protein labeling followed by mass spectrometry of the labeled proteins to determine the proteome of the region of interest. We performed proximity-based proteomics in the cyanobacterium Synechococcus sp. PCC 7002 with the APEX2 enzyme, an engineered ascorbate peroxidase. We determined the proteome of the thylakoid lumen, a region of the cell that has remained challenging to study with existing methods, using a translational fusion between APEX2 and PsbU, a lumenal subunit of photosystem II. Our results demonstrate the power of APEX2 as a tool to study the cell biology of intracellular features and processes, including photosystem II assembly in cyanobacteria, with enhanced spatiotemporal resolution.

Neutralisation of SARS-CoV-2 by anatomical embalming solutions.

Teaching and learning anatomy by using human cadaveric specimens has been a foundation of medical and biomedical teaching for hundreds of years. Therefore, the majority of institutions that teach topographical anatomy rely on body donation programmes to provide specimens for both undergraduate and postgraduate teaching of gross anatomy. The COVID-19 pandemic has posed an unprecedented challenge to anatomy teaching because of the suspension of donor acceptance at most institutions. This was largely due to concerns about the potential transmissibility of the SARS-CoV-2 virus and the absence of data about the ability of embalming solutions to neutralise the virus. Twenty embalming solutions commonly used in institutions in the United Kingdom and Ireland were tested for their ability to neutralise SARS-CoV-2, using an established cytotoxicity assay. All embalming solutions tested neutralised SARS-CoV-2, with the majority of solutions being effective at high-working dilutions. These results suggest that successful embalming with the tested solutions can neutralise the SARS-CoV-2 virus, thereby facilitating the safe resumption of body donation programmes and cadaveric anatomy teaching.

Discovery of CYR715: A novel carboxylic acid-containing soluble guanylate cyclase stimulator.

Soluble guanylate cyclase (sGC) is a clinically validated therapeutic target in the treatment of pulmonary hypertension. Modulators of sGC have the potential to treat diseases that are affected by dysregulation of the NO-sGC-cGMP signal transduction pathway. This letter describes the SAR efforts that led to the discovery of CYR715, a novel carboxylic acid-containing sGC stimulator, with an improved metabolic profile relative to our previously described stimulator, IWP-051. CYR715 addressed potential idiosyncratic drug toxicity (IDT) liabilities associated with the formation of reactive, migrating acyl glucuronides (AG) found in related carboxylic acid-containing analogs and demonstrated high oral bioavailability in rat and dose-dependent hemodynamic pharmacology in normotensive Sprague-Dawley rats.

Topography of choriocapillaris flow deficit predicts development of neovascularization or atrophy in age-related macular degeneration.

PURPOSE: To evaluate the relationship between choriocapillaris (CC), flow deficits (FD), and structural optical coherence tomography (OCT) biomarkers, and the progression of intermediate age-related macular degeneration (iAMD) to complete retinal pigment epithelial and outer retinal atrophy (cRORA) or macular neovascularization (MNV). METHODS: Consecutive patients with iAMD were sequentially reviewed to define three equal sized groups: progressed to MNV, progressed to cRORA, or remained stable over 12 months of follow-up. Odds ratios for progression to cRORA and MNV were estimated by logistic regression for intraretinal hyperreflective foci (IHRF), hyporeflective drusen cores (hDC), subretinal drusenoid deposits (SDDs), high central drusen volume, fellow eye with late AMD, and peripheral and central CC FD. RESULTS: Thirty iAMD eyes from 30 patients were enrolled into each group. The CC FD was greater in the peripheral sectors of the macula of eyes which progressed to cRORA compared to the other two groups (P < 0.0001). The central CC FD was also significantly impaired in eyes that progressed to cRORA or MNV compared to eyes that did not progress (P = 0.001 and P = 0.02, respectively). CC FD in the peripheral macula was significantly and independently associated with the development of cRORA, while CC FD in the center was significantly and independently associated with the development of MNV. CONCLUSIONS: While the CC is diffusely impaired throughout the macula in iAMD eyes that progress to cRORA, it is relatively spared in the more peripheral macula among eyes which progress to MNV. These differential findings may have implications for the pathophysiology of the different late-stage manifestations of AMD.

CHORIOCAPILLARIS FLOW DEFICITS AS A RISK FACTOR FOR PROGRESSION OF AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To evaluate the association between choriocapillaris (CC) flow deficits and structural optical coherence tomography biomarkers and the progression of intermediate age-related macular degeneration (iAMD) to complete retinal pigment epithelial and outer retinal atrophy. METHODS: Retrospective analysis of consecutive patients with iAMD with a minimum follow-up of 12 months. Odds ratios of intraretinal hyperreflective foci, hyporeflective drusen cores, subretinal drusenoid deposits, the presence of drusen volume ≥0.03 mm3 within a central 3-mm circle, fellow eye with late stage of AMD, and CC flow deficits at baseline and months of follow-up were estimated from logistic regression. RESULTS: A total of 112 eyes with iAMD were included. Eyes that progressed were significantly more likely to show intraretinal hyperreflective foci, hyporeflective drusen cores, and drusen volume ≥0.03 mm3. The CC flow deficit was also significantly greater in eyes that developed complete retinal pigment epithelial and outer retinal atrophy. Intraretinal hyperreflective foci, hyporeflective drusen cores, drusen volume ≥0.03 mm3, and higher CC flow deficits were significantly and independently associated with the development of complete retinal pigment epithelial and outer retinal atrophy. CONCLUSION: The CC flow deficit was significantly greater in iAMD eyes that progressed to complete retinal pigment epithelial and outer retinal atrophy and remained an independent risk factor when structural optical coherence tomography biomarkers were considered. CC flow deficits may be useful for enhancing risk stratification and prognostication of patients with iAMD.