Rescue of Fragile X Syndrome Neurons by DNA Methylation Editing of the FMR1 Gene.

Fragile X syndrome (FXS), the most common genetic form of intellectual disability in males, is caused by silencing of the FMR1 gene associated with hypermethylation of the CGG expansion mutation in the 5' UTR of FMR1 in FXS patients. Here, we applied recently developed DNA methylation editing tools to reverse this hypermethylation event. Targeted demethylation of the CGG expansion by dCas9-Tet1/single guide RNA (sgRNA) switched the heterochromatin status of the upstream FMR1 promoter to an active chromatin state, restoring a persistent expression of FMR1 in FXS iPSCs. Neurons derived from methylation-edited FXS iPSCs rescued the electrophysiological abnormalities and restored a wild-type phenotype upon the mutant neurons. FMR1 expression in edited neurons was maintained in vivo after engrafting into the mouse brain. Finally, demethylation of the CGG repeats in post-mitotic FXS neurons also reactivated FMR1. Our data establish that demethylation of the CGG expansion is sufficient for FMR1 reactivation, suggesting potential therapeutic strategies for FXS.

Transcription Factors Activate Genes through the Phase-Separation Capacity of Their Activation Domains.

Gene expression is controlled by transcription factors (TFs) that consist of DNA-binding domains (DBDs) and activation domains (ADs). The DBDs have been well characterized, but little is known about the mechanisms by which ADs effect gene activation. Here, we report that diverse ADs form phase-separated condensates with the Mediator coactivator. For the OCT4 and GCN4 TFs, we show that the ability to form phase-separated droplets with Mediator in vitro and the ability to activate genes in vivo are dependent on the same amino acid residues. For the estrogen receptor (ER), a ligand-dependent activator, we show that estrogen enhances phase separation with Mediator, again linking phase separation with gene activation. These results suggest that diverse TFs can interact with Mediator through the phase-separating capacity of their ADs and that formation of condensates with Mediator is involved in gene activation.

YY1 Is a Structural Regulator of Enhancer-Promoter Loops.

There is considerable evidence that chromosome structure plays important roles in gene control, but we have limited understanding of the proteins that contribute to structural interactions between gene promoters and their enhancer elements. Large DNA loops that encompass genes and their regulatory elements depend on CTCF-CTCF interactions, but most enhancer-promoter interactions do not employ this structural protein. Here, we show that the ubiquitously expressed transcription factor Yin Yang 1 (YY1) contributes to enhancer-promoter structural interactions in a manner analogous to DNA interactions mediated by CTCF. YY1 binds to active enhancers and promoter-proximal elements and forms dimers that facilitate the interaction of these DNA elements. Deletion of YY1 binding sites or depletion of YY1 protein disrupts enhancer-promoter looping and gene expression. We propose that YY1-mediated enhancer-promoter interactions are a general feature of mammalian gene control.

A distinct core regulatory module enforces oncogene expression in KMT2A-rearranged leukemia.

Acute myeloid leukemia with KMT2A (MLL) rearrangements is characterized by specific patterns of gene expression and enhancer architecture, implying unique core transcriptional regulatory circuitry. Here, we identified the transcription factors MEF2D and IRF8 as selective transcriptional dependencies of KMT2A-rearranged AML, where MEF2D displays partially redundant functions with its paralog, MEF2C. Rapid transcription factor degradation followed by measurements of genome-wide transcription rates and superresolution microscopy revealed that MEF2D and IRF8 form a distinct core regulatory module with a narrow direct transcriptional program that includes activation of the key oncogenes MYC, HOXA9, and BCL2. Our study illustrates a mechanism of context-specific transcriptional addiction whereby a specific AML subclass depends on a highly specialized core regulatory module to directly enforce expression of common leukemia oncogenes.

Differential cofactor dependencies define distinct types of human enhancers.

All multicellular organisms rely on differential gene transcription regulated by genomic enhancers, which function through cofactors that are recruited by transcription factors1,2. Emerging evidence suggests that not all cofactors are required at all enhancers3-5, yet whether these observations reflect more general principles or distinct types of enhancers remained unknown. Here we categorized human enhancers by their cofactor dependencies and show that these categories provide a framework to understand the sequence and chromatin diversity of enhancers and their roles in different gene-regulatory programmes. We quantified enhancer activities along the entire human genome using STARR-seq6 in HCT116 cells, following the rapid degradation of eight cofactors. This analysis identified different types of enhancers with distinct cofactor requirements, sequences and chromatin properties. Some enhancers were insensitive to the depletion of the core Mediator subunit MED14 or the bromodomain protein BRD4 and regulated distinct transcriptional programmes. In particular, canonical Mediator7 seemed dispensable for P53-responsive enhancers, and MED14-depleted cells induced endogenous P53 target genes. Similarly, BRD4 was not required for the transcription of genes that bear CCAAT boxes and a TATA box (including histone genes and LTR12 retrotransposons) or for the induction of heat-shock genes. This categorization of enhancers through cofactor dependencies reveals distinct enhancer types that can bypass broadly utilized cofactors, which illustrates how alternative ways to activate transcription separate gene expression programmes and provide a conceptual framework to understand enhancer function and regulatory specificity.

Mediator Condensates Localize Signaling Factors to Key Cell Identity Genes.

The gene expression programs that define the identity of each cell are controlled by master transcription factors (TFs) that bind cell-type-specific enhancers, as well as signaling factors, which bring extracellular stimuli to these enhancers. Recent studies have revealed that master TFs form phase-separated condensates with the Mediator coactivator at super-enhancers. Here, we present evidence that signaling factors for the WNT, TGF-ß, and JAK/STAT pathways use their intrinsically disordered regions (IDRs) to enter and concentrate in Mediator condensates at super-enhancers. We show that the WNT coactivator ß-catenin interacts both with components of condensates and DNA-binding factors to selectively occupy super-enhancer-associated genes. We propose that the cell-type specificity of the response to signaling is mediated in part by the IDRs of the signaling factors, which cause these factors to partition into condensates established by the master TFs and Mediator at genes with prominent roles in cell identity.

MeCP2 links heterochromatin condensates and neurodevelopmental disease.

Methyl CpG binding protein 2 (MeCP2) is a key component of constitutive heterochromatin, which is crucial for chromosome maintenance and transcriptional silencing1-3. Mutations in the MECP2 gene cause the progressive neurodevelopmental disorder Rett syndrome3-5, which is associated with severe mental disability and autism-like symptoms that affect girls during early childhood. Although previously thought to be a dense and relatively static structure1,2, heterochromatin is now understood to exhibit properties consistent with a liquid-like condensate6,7. Here we show that MeCP2 is a dynamic component of heterochromatin condensates in cells, and is stimulated by DNA to form liquid-like condensates. MeCP2 contains several domains that contribute to the formation of condensates, and mutations in MECP2 that lead to Rett syndrome disrupt the ability of MeCP2 to form condensates. Condensates formed by MeCP2 selectively incorporate and concentrate heterochromatin cofactors rather than components of euchromatic transcriptionally active condensates. We propose that MeCP2 enhances the separation of heterochromatin and euchromatin through its condensate partitioning properties, and that disruption of condensates may be a common consequence of mutations in MeCP2 that cause Rett syndrome.

Visual Acuity Outcomes and Complications after Intraocular Lens Exchange: An IRIS® Registry (Intelligent Research in Sight) Analysis.

PURPOSE: To assess risk factors for worse visual acuity (VA) outcomes after intraocular lens (IOL) exchange, and the most common postsurgical complications. DESIGN: Retrospective cohort study. PARTICIPANTS: Eyes from patients 18 years of age and older in the IRIS® Registry (Intelligent Research in Sight) that underwent IOL exchange in the United States between 2013 and 2019. METHODS: Vision improvement compared with baseline was determined at 1 year after surgery. A multivariable generalized estimating equation model adjusting for demographic factors and baseline vision was used to identify factors associated with VA worse than 20/40 at 1 year. MAIN OUTCOME MEASURES: Visual outcomes and postoperative complications after lens exchange. RESULTS: A total of 46 063 procedures (n = 41 925 unique patients) were included in the analysis. Overall, VA improved from a mean ± standard deviation (SD) of 0.53 ± 0.58 logarithm of the minimum angle of resolution (logMAR; Snellen equivalent, 20/70) before surgery to a mean ± SD of 0.31 ± 0.40 logMAR (Snellen equivalent, 20/40) at 1 year. Among eyes with VA recorded at both baseline and 1 year after surgery, 60.5% achieved VA of 20/40 or better at 1 year. Vision of worse than 20/40 at 1 year was associated with greater age (odds ratio [OR], 1.16 per 5-year increase; 95% confidence interval [CI], 1.14-1.18) and higher logMAR baseline VA (OR, 1.14 per 0.1-logMAR increase; 95% CI, 1.14-1.15), as well as Black or African American (OR, 1.96; 95% CI, 1.68-2.28), Hispanic (OR, 1.82; 95% CI, 1.59-2.08), and Asian (OR, 1.48; 95% CI, 1.21-1.81) race or ethnicity versus White race, Medicaid (OR, 1.78; 95% CI, 1.40-2.25) versus private insurance, smoking history (OR, 1.22; 95% CI, 1.11-1.35), and concurrent anterior (OR, 1.65; 95% CI, 1.51-1.81) and posterior (OR, 1.53; 95% CI, 1.41-1.66) vitrectomy versus no vitrectomy. Female sex was associated with better VA at 1 year. At 1 year, epiretinal membrane (10.9%), mechanical lens complication (9.4%), and dislocation of the replacement lens (7.1%) were the most common complications. CONCLUSIONS: In this large national cohort, the annual number of IOL exchanges rose steadily over time. Vision improved in 60.2% of patients; worse visual outcomes were associated with greater age, worse baseline vision, Black race, Hispanic ethnicity, Medicaid insurance, smoking, and concurrent vitrectomy. Epiretinal membrane was the most common complication. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Chromatin Kinases Act on Transcription Factors and Histone Tails in Regulation of Inducible Transcription.

The inflammatory response requires coordinated activation of both transcription factors and chromatin to induce transcription for defense against pathogens and environmental insults. We sought to elucidate the connections between inflammatory signaling pathways and chromatin through genomic footprinting of kinase activity and unbiased identification of prominent histone phosphorylation events. We identified H3 serine 28 phosphorylation (H3S28ph) as the principal stimulation-dependent histone modification and observed its enrichment at induced genes in mouse macrophages stimulated with bacterial lipopolysaccharide. Using pharmacological and genetic approaches, we identified mitogen- and stress-activated protein kinases (MSKs) as primary mediators of H3S28ph in macrophages. Cell-free transcription assays demonstrated that H3S28ph directly promotes p300/CBP-dependent transcription. Further, MSKs can activate both signal-responsive transcription factors and the chromatin template with additive effects on transcription. Specific inhibition of MSKs in macrophages selectively reduced transcription of stimulation-induced genes. Our results suggest that MSKs incorporate upstream signaling inputs and control multiple downstream regulators of inducible transcription.

The impact of month and season on the incidence of giant cell arteritis: an Intelligent Research in Sight (IRIS) Registry analysis.

PURPOSE: Previous investigations into the relationship between season and the incidence of giant cell arteritis (GCA) have produced conflicting results. This study aimed to explore the impact of season and new diagnoses of GCA in a more definitive sense by employing the large dataset of the Intelligent Research in Sight (IRIS) database. METHODS: The IRIS Registry was queried to identify new cases of GCA from 2013 to 2021. Statistical analyses were performed to determine the significance of the relationship between the time of year and the incidence of GCA on regional and nationwide bases via Cochran's Q statistical test. RESULTS: A total of 27,339 eyes with a new diagnosis of GCA were identified. Neither the month nor the season of the year correlated with the incidence of GCA, regardless of geographic location within the USA (p > 0.05 for each variable). CONCLUSIONS: In the USA, the incidence of GCA does not appear to vary by month or season. While this finding contradicts certain previous studies that identified a relationship, the cohort of patients identified from the IRIS Registry is much larger than that of previous investigations. Clinicians should be mindful of the possibility of GCA, regardless of the time of the year.

Loss to Follow-up in Patients with Neovascular Age-Related Macular Degeneration Treated with Anti-VEGF Therapy in the United States in the IRIS® Registry.

PURPOSE: To determine the incidence of being lost to follow-up (LTFU) and nonpersistence in patients with neovascular age-related macular degeneration (AMD) treated with anti-VEGF injections in the United States. DESIGN: Retrospective cohort study using the IRIS® (Intelligent Research in Sight) Registry data. PARTICIPANTS: One hundred fifty-six thousand three hundred twenty-seven treatment-naive patients with neovascular AMD who subsequently were treated with anti-VEGF therapy from 2013 through 2015 and followed up through 2019. METHODS: Multivariable logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). MAIN OUTCOME MEASURES: Being LTFU was defined as no follow-up within 12 months from last intravitreal injection. Nonpersistence was defined as no follow-up within 6 months from last intravitreal injection. RESULTS: For neovascular AMD, 11.6% of patients (95% CI, 11.4%-11.7%) were LTFU, and 88.4% of patients were followed up within 12 months. The rate of being LTFU generally was higher with increasing age, with odds of being LTFU greatest for patients between 81 and 84 years of age (OR, 2.51; 95% CI, 2.31-2.74; P < 0.001) compared with patients 70 years of age and younger. Odds of being LTFU for Black or African American patients (OR, 1.32; 95% CI, 1.08-1.61; P = 0.007) were greater than for White patients. Odds of being LTFU were higher for patients with Medicaid insurance (OR, 1.27; 95% CI, 1.01-1.60; P = 0.04) and lower for patients with Medicare Fee-For-Service insurance (OR, 0.69; 95% CI, 0.64-0.74; P < 0.001) than for patients with private insurance. Furthermore, 14.3% (95% CI, 14.1-14.4) of patients were nonpersistent, and 85.7% of patients underwent follow-up within 6 months. Odds of nonpersistence also were greatest among patients between 81 and 84 years of age (OR, 2.13; 95% CI, 1.98-2.29; P < 0.001) compared with patients 70 years of age or younger. Odds of nonpersistence for Black or African-American patients (OR, 1.38; 95% CI, 1.15-1.65; P < 0.001) and Hispanic patients (OR, 1.13; 95% CI, 1.03-1.24; P = 0.009) were greater than odds for White patients. CONCLUSIONS: Nearly 1 of 9 patients with neovascular AMD treated with anti-VEGF injections became LTFU, whereas 1 of 7 patients were nonpersistent. Risk factors identified included increasing age, male sex, unilateral involvement, diabetes, Medicaid insurance, and race or ethnicity. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Multivariable Analyses of Amblyopia Treatment Outcomes from a Clinical Data Registry.

PURPOSE: To present multivariable analyses of factors associated with amblyopia treatment success using outcomes from a clinical registry. DESIGN: Retrospective database study. PARTICIPANTS: New patients 3 to 12 years of age being enrolled in the registry from 2013 to 2019. MAIN OUTCOME MEASURE: The IRIS-50 is an outcome measure for amblyopia treatment developed by the American Academy of Ophthalmology for use with data in the Intelligent Research in Sight (IRIS®) Registry. The measure specifications include unilateral amblyopia associated with strabismus, refractive error, or both. METHODS: Clinical care prescribed by the ophthalmologist. RESULTS: Eighteen thousand eight hundred forty-one children 3 to 7 years of age were eligible for IRIS-50, with 77.3% successful. Nine thousand seven hundred sixty-two children 8 to 12 years of age were eligible, with 55.5% successful. For the younger age group, multivariable analyses found that odds ratios (ORs) for success were significantly lower for Black children (0.71; 95% confidence interval [CI], 0.62-0.83) compared with White children. Medicaid insurance was associated independently with significantly lower success (OR, 0.65; 95% CI, 0.60-0.71). Among older children, Black children were less likely to be treated successfully (OR, 0.81; 95% CI, 0.68-0.96) compared with White children, whereas Hispanic children showed an increased chance of success (OR, 1.16; 95% CI, 1.03-1.31). Medicaid insurance for the older children also was associated with a decreased chance of success (OR, 0.84; 95% CI, 0.77-0.93). CONCLUSIONS: Amblyopia treatment outcomes measured by IRIS-50 were significantly poorer for Black children and those with Medicaid insurance 3 to 12 years of age. Disparate health outcomes demonstrated for these two factors emphasize the need to develop and test strategies to improve treatment outcomes for these children.

Engineering of a Histone-Recognition Domain in Dnmt3a Alters the Epigenetic Landscape and Phenotypic Features of Mouse ESCs.

Histone modification and DNA methylation are associated with varying epigenetic "landscapes," but detailed mechanistic and functional links between the two remain unclear. Using the ATRX-DNMT3-DNMT3L (ADD) domain of the DNA methyltransferase Dnmt3a as a paradigm, we apply protein engineering to dissect the molecular interactions underlying the recruitment of this enzyme to specific regions of chromatin in mouse embryonic stem cells (ESCs). By rendering the ADD domain insensitive to histone modification, specifically H3K4 methylation or H3T3 phosphorylation, we demonstrate the consequence of dysregulated Dnmt3a binding and activity. Targeting of a Dnmt3a mutant to H3K4me3 promoters decreases gene expression in a subset of developmental genes and alters ESC differentiation, whereas aberrant binding of another mutant to H3T3ph during mitosis promotes chromosome instability. Our studies support the general view that histone modification "reading" and DNA methylation are closely coupled in mammalian cells, and suggest an avenue for the functional assessment of chromatin-associated proteins.

Disparities in Visual Acuity Outcomes after Endothelial Keratoplasty: An Intelligent Research in Sight Registry Analysis.

PURPOSE: To assess risk factors for lack of vision improvement after endothelial keratoplasty (EK). DESIGN: Retrospective cohort study. PARTICIPANTS: Patients aged 18 years and older in the Intelligent Research in Sight (IRIS®) Registry who underwent EK surgery in the United States between 2013 and 2018. METHODS: Change in visual acuity (VA) relative to baseline were determined at 6 months and 1 year. A multivariable population-average marginal model estimated using generalized estimating equations adjusting for sociodemographic factors, baseline vision, surgical indication, ocular comorbidities, and postoperative complications was used to identify factors associated with worse VA outcomes. MAIN OUTCOME MEASURES: Visual acuity and lack of VA improvement at 1 year compared with preoperative status. RESULTS: A total of 30 600 EK procedures (N = 25 666 unique patients) were included in the analysis. Overall, VA improved from median logarithm of the minimum angle of resolution (logMAR) 0.54 (Snellen 20/69) (interquartile range [IQR] ± 0.70) preoperatively to median logMAR 0.40 (20/50) (IQR ± 0.36) at 6 months and median logMAR 0.30 (20/40) (IQR ± 0.36) at 1 year postoperatively. A total of 30.3% of the overall cohort, 29.8% of Fuchs' endothelial corneal dystrophy (FECD) subgroup, and 27.4% of the bullous keratopathy (BK) subgroup did not show visual improvement at 1 year postoperatively. In the FECD subgroup, older age (risk ratio [RR], 1.05 per 5-year increase, 95% confidence interval [CI], 1.03-1.07) and female sex (RR, 1.10, 95% CI, 1.04-1.16) were associated with VA worse than or equal to baseline at 1 year postoperatively. In both FECD and BK subgroups, eyes with higher baseline logMAR VA (per 0.1 unit increase in logMAR) were more likely to have visual improvement postoperatively (FECD: RR, 0.82, 95% CI, 0.81-0.84; BK: RR, 0.91, 95% CI, 0.91-0.92), whereas postoperative rebubbling (FECD: RR, 1.10, 95% CI, 1.02-1.19; BK: RR, 1.31, 95% CI, 1.17-1.48) and repeat keratoplasties (FECD: RR, 1.41, 95% CI, 1.32-1.52; BK: RR, 1.42, 95% CI, 1.28-1.57) were associated with higher risk of no VA improvement. CONCLUSIONS: In this large national cohort, postoperative rebubblings and repeat keratoplasties were identified as independent factors associated with worse VA outcomes after EK for both FECD and BK subgroups. Older age and female gender were associated with worse VA outcomes after EK in the FECD subgroup.

Mutational landscape of primary, metastatic, and recurrent ovarian cancer reveals c-MYC gains as potential target for BET inhibitors.

Ovarian cancer remains the most lethal gynecologic malignancy. We analyzed the mutational landscape of 64 primary, 41 metastatic, and 17 recurrent fresh-frozen tumors from 77 patients along with matched normal DNA, by whole-exome sequencing (WES). We also sequenced 13 pairs of synchronous bilateral ovarian cancer (SBOC) to evaluate the evolutionary history. Lastly, to search for therapeutic targets, we evaluated the activity of the Bromodomain and Extra-Terminal motif (BET) inhibitor GS-626510 on primary tumors and xenografts harboring c-MYC amplifications. In line with previous studies, the large majority of germline and somatic mutations were found in BRCA1/2 (21%) and TP53 (86%) genes, respectively. Among mutations in known cancer driver genes, 77% were transmitted from primary tumors to metastatic tumors, and 80% from primary to recurrent tumors, indicating that driver mutations are commonly retained during ovarian cancer evolution. Importantly, the number, mutation spectra, and signatures in matched primary-metastatic tumors were extremely similar, suggesting transcoelomic metastases as an early dissemination process using preexisting metastatic ability rather than an evolution model. Similarly, comparison of SBOC showed extensive sharing of somatic mutations, unequivocally indicating a common ancestry in all cases. Among the 17 patients with matched tumors, four patients gained PIK3CA amplifications and two patients gained c-MYC amplifications in the recurrent tumors, with no loss of amplification or gain of deletions. Primary cell lines and xenografts derived from chemotherapy-resistant tumors demonstrated sensitivity to JQ1 and GS-626510 (P = 0.01), suggesting that oral BET inhibitors represent a class of personalized therapeutics in patients harboring recurrent/chemotherapy-resistant disease.

Increased relative risk of delayed hemorrhage in patients taking anticoagulant/antiplatelet medications with concurrent aspirin therapy: implications for clinical practice based on 3-year retrospective analysis in a large health system.

PURPOSE: The incidence of delayed posttraumatic intracranial hemorrhage (DH) in patients on anticoagulant (AC) and antiplatelet (AP) medications, especially with concurrent aspirin therapy, is not well established, with studies reporting disparate results with between 1-10% risk of DH and 0-3% mortality. The purpose of this 3-year retrospective study is to evaluate the true risk of DH in patients on AP/AC medications with or without concurrent aspirin therapy. METHODS: One thousand forty-six patients taking AP and AC medications presenting to network emergency departments with head trauma who had repeat CT to evaluate for DH were included in the study. Repeat examinations were typically performed within 24 h (average follow-up time was 21 h and 99% were within 3 days). Mean time to DH was 20 h. All positive studies were reviewed by two board-certified neuroradiologists. Patients were excluded from the study if hemorrhage was retrospectively identified on the initial examination. Cases were reclassified as negative if hemorrhage on the follow-up examination was thought to be not present or artifactual. Cases were considered positive if the initial examination was negative and the follow-up examination demonstrated new hemorrhage. RESULTS: Overall, there was 1.91% incidence (20 patients) of DH and 0.3% overall mortality (3 patients). The group of patients taking warfarin or AP agents demonstrated a significantly higher rate of DH (3.2% compared to 0.9%) and higher mortality (0.9% compared to 0.0%) compared to the DOAC group (p < 0.01). The risk of DH in patients taking AC or AP agents with aspirin (13/20 cases) was significantly higher (RR 3.8, p < 0.01) than that of patients taking AC or AP alone (7/20 cases). CONCLUSION: The risk of DH was significantly higher in patients taking aspirin in addition to AC/AP medications. Repeat imaging should be obtained for trauma patients taking AC/AP agents with concurrent aspirin. The rate of DH was also significantly higher in patients taking warfarin or AP agents when compared to patients taking DOACs. Repeat examination should be strongly considered on patients taking warfarin or AP agents without aspirin. Given the relatively low risk of DH in patients taking DOACs alone, repeat imaging could be reserved for patients with external signs of trauma or dangerous mechanism of injury.

A Comparison of WebRTC and Conventional Videoconferencing for Synchronized Remote Medical Image Presentation.

DICOM viewers must fulfill roles beyond primary diagnostic interpretation, including serving as presentation tools in teaching and multidisciplinary conferences, thereby enabling multiple individuals to review images collaboratively in real time. When in-person gathering is not possible, a variety of solutions have been deployed to maintain the ability for spatially separated users to view medical images simultaneously. These approaches differ in their backend architectures, utilization of application-specific optimizations, and ultimately in their end user satisfaction. In this work, we systematically compare the performance of conventional screensharing using a videoconferencing application with that of a custom, synchronized DICOM viewer linked using Web Real Time Communications (WebRTC) technology. We find superior performance for the WebRTC method with regard to image quality and latency across a range of simulated adverse network conditions, and we show how increasing the number of conference participants differentially affects the bandwidth requirements of the two viewing solutions. In addition, we compare these two approaches in a real-world teaching scenario and gather the feedback of trainee and faculty radiologists, who we found to favor the WebRTC method for its decreased latency, improved image quality, ease of setup, and overall experience. Ultimately, our results demonstrate the value of application-specific solutions for the remote synchronized viewing of medical imaging, which, given the recent increase in reliance on remote collaboration, may constitute a significant consideration for future enterprise viewer procurement decisions.

The DIOS framework for optimizing infectious disease surveillance: Numerical methods for simulation and multi-objective optimization of surveillance network architectures.

Infectious disease surveillance systems provide vital data for guiding disease prevention and control policies, yet the formalization of methods to optimize surveillance networks has largely been overlooked. Decisions surrounding surveillance design parameters-such as the number and placement of surveillance sites, target populations, and case definitions-are often determined by expert opinion or deference to operational considerations, without formal analysis of the influence of design parameters on surveillance objectives. Here we propose a simulation framework to guide evidence-based surveillance network design to better achieve specific surveillance goals with limited resources. We define evidence-based surveillance design as an optimization problem, acknowledging the many operational constraints under which surveillance systems operate, the many dimensions of surveillance system design, the multiple and competing goals of surveillance, and the complex and dynamic nature of disease systems. We describe an analytical framework-the Disease Surveillance Informatics Optimization and Simulation (DIOS) framework-for the identification of optimal surveillance designs through mathematical representations of disease and surveillance processes, definition of objective functions, and numerical optimization. We then apply the framework to the problem of selecting candidate sites to expand an existing surveillance network under alternative objectives of: (1) improving spatial prediction of disease prevalence at unmonitored sites; or (2) estimating the observed effect of a risk factor on disease. Results of this demonstration illustrate how optimal designs are sensitive to both surveillance goals and the underlying spatial pattern of the target disease. The findings affirm the value of designing surveillance systems through quantitative and adaptive analysis of network characteristics and performance. The framework can be applied to the design of surveillance systems tailored to setting-specific disease transmission dynamics and surveillance needs, and can yield improved understanding of tradeoffs between network architectures.

Protection studies of an excretory-secretory protein HcABHD against Haemonchus contortus infection.

Unlike the successful immunization of native H. contortus antigens that contributed to the realization of the first commercial vaccine Barbervax, not many studies revealed the encouraging protective efficacies of recombinant H. contortus antigens in laboratory trials or under field conditions. In our preliminary study, H. contortus α/ß-hydrolase domain protein (HcABHD) was demonstrated to be an immunomodulatory excretory-secretory (ES) protein that interacts with goat T cells. We herein evaluated the protective capacities of two HcABHD preparations, recombinant HcABHD (rHcABHD) antigen and anti-rHcABHD IgG, against H. contortus challenge via active and passive immunization trials, respectively. Parasitological parameter, antibody responses, hematological pathology and cytokine profiling in unchallenged and challenged goats were monitored and determined throughout both trials. Subcutaneous administration of rHcABHD with Freund adjuvants elicited protective immune responses in challenged goats, diminishing cumulative fecal egg counts (FEC) and total worm burden by 54.0% and 74.2%, respectively, whereas passive immunization with anti-rHcABHD IgG conferred substantial protection to challenged goats by generating a 51.5% reduction of cumulative FEC and a 73.8% reduction of total worm burden. Additionally, comparable changes of mucosal IgA levels, circulating IgG levels, hemoglobin levels, and serum interleukin (IL)-4 and IL-17A levels were observed in rHcABHD protein/anti-rHcABHD IgG immunized goats in both trials. Taken together, the recombinant version of HcABHD might have further application under field conditions in protecting goats against H. contortus infection, and the integrated immunological pipeline of ES antigen identification, screening and characterization may provide new clues for further development of recombinant subunit vaccines to control H. contortus.

The excretory-secretory antigen HcADRM1 to generate protective immunity against Haemonchus contortus.

The prevention, treatment and control of Haemonchus contortus have been increasingly problematic due to its widespread occurrence and anthelmintic resistance. There are very few descriptions of recombinant antigens being protective for H. contortus, despite the success of various native antigen preparations, including Barbervax. We recently identified an H. contortus excretory­secretory antigen, H. contortus adhesion-regulating molecule 1 (HcADRM1), that served as an immunomodulator to impair host T-cell functions. Given the prophylactic potential of HcADRM1 protein as a vaccine candidate, we hereby assessed the efficacies of HcADRM1 preparations against H. contortus infection. Parasitological and immunological parameters were evaluated throughout all time points of the trials, including fecal egg counts (FEC), abomasal worm burdens, complete blood counts, cytokine production profiles and antibody responses. Active vaccination with recombinant HcADRM1 (rHcADRM1) protein induced protective immunity in inoculated goats, resulting in reductions of 48.9 and 58.6% in cumulative FEC and worm burdens. Simultaneously, passive administration of anti-HcADRM1 antibodies generated encouraging levels of protection with 46.7 and 56.2% reductions in cumulative FEC and worm burdens in challenged goats. In addition, HcADRM1 preparations-immunized goats showed significant differences in mucosal and serum antigen-specific immunoglobulin G (IgG) levels, total mucosal IgA levels, haemoglobin values and circulating interferon-γ, interleukin (IL)-4 and IL-17A production compared to control goats in both trials. The preliminary data of these laboratory trials validated the immunoprophylactic effects of rHcADRM1 protein. It can be pursued as a potential vaccine antigen to develop an effective recombinant subunit vaccine against H. contortus under field conditions.