512 results on '"Cohen, BA"'
Search Results
102. Pediatric dermatology: what's your Dx? Sole manifestation: nodule in a newborn boy.
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Cohen BA
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- 2002
103. Recognizing and treating toilet-seat contact dermatitis in children.
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Litvinov IV, Sugathan P, and Cohen BA
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- 2010
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104. Dermatology: what's your Dx? A newborn with a brown spot.
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Boudreaux JM and Cohen BA
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- 2009
105. Identification, causation, alleviation, and prevention of complications (ICAP): an approach to symptom and disability management in multiple sclerosis.
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Cohen BA
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- 2008
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106. Insect bite-induced hypersensitivity and the SCRATCH principles: a new approach to papular urticaria.
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Hernandez RG and Cohen BA
- Abstract
Insect bites and the associated hypersensitivity reactions known as papular urticaria account for a significant number of all referrals from pediatricians and dermatologists to our pediatric dermatology clinic. Unfortunately, children affected by these eruptions are frequently misdiagnosed and often subject to expensive evaluations including invasive and unnecessary procedures. Here we review the course of 4 children with the typical physical findings and natural history of these reactions. On the basis of our clinical findings and experience with this patient population, we propose a set of principles (termed 'SCRATCH') as clinical features to aid clinicians in making an early and accurate clinical diagnosis. We conclude that a more appropriate term for future study and diagnosis of this entity is insect bite-induced hypersensitivity. [ABSTRACT FROM AUTHOR]
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- 2006
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107. Identifying and treating patients with suboptimal responses.
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Cohen BA, Khan O, Jeffery DR, Bashir K, Rizvi SA, Fox EJ, Agius M, Bashir R, Collins TE, Herndon R, Kinkel P, Mikol DD, Picone MA, Rivera V, Tornatore C, Zwibel H, Cohen, B A, Khan, O, Jeffery, D R, and Bashir, K
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- 2004
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108. Mitoxantrone treatment of multiple sclerosis: safety considerations.
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Cohen BA, Mikol DD, Cohen, Bruce A, and Mikol, Daniel D
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- 2004
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109. A call to root out 'pejorativism' in the medical lexicon.
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Feingold M and Cohen BA
- Published
- 2003
110. A mystery: ring around the moles.
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Cohen BA
- Published
- 2003
111. Carbon monoxide poisoning in the aftermath of Hurricane Fran.
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Cohen BA, Stolp BW, Dear GD, Moon RE, and Frazier LM
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- 1999
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112. Active learning of enhancers and silencers in the developing neural retina.
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Friedman RZ, Ramu A, Lichtarge S, Wu Y, Tripp L, Lyon D, Myers CA, Granas DM, Gause M, Corbo JC, Cohen BA, and White MA
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- Animals, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Trans-Activators genetics, Trans-Activators metabolism, Binding Sites, Deep Learning, Humans, Mice, Transcription Factors genetics, Transcription Factors metabolism, Retina metabolism, Enhancer Elements, Genetic genetics
- Abstract
Deep learning is a promising strategy for modeling cis-regulatory elements. However, models trained on genomic sequences often fail to explain why the same transcription factor can activate or repress transcription in different contexts. To address this limitation, we developed an active learning approach to train models that distinguish between enhancers and silencers composed of binding sites for the photoreceptor transcription factor cone-rod homeobox (CRX). After training the model on nearly all bound CRX sites from the genome, we coupled synthetic biology with uncertainty sampling to generate additional rounds of informative training data. This allowed us to iteratively train models on data from multiple rounds of massively parallel reporter assays. The ability of the resulting models to discriminate between CRX sites with identical sequence but opposite functions establishes active learning as an effective strategy to train models of regulatory DNA. A record of this paper's transparent peer review process is included in the supplemental information., Competing Interests: Declaration of interests B.A.C. is on the scientific advisory board of Patch Biosciences., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
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- 2025
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113. Advancements in Noninvasive Imaging: Optical Coherence Tomography for Evaluating Therapeutic Efficacy in Vitiligo.
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Tan IJ, Wolfe SM, and Cohen BA
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- 2025
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114. Advances in Topical Therapies for Clinically Relevant and Prevalent Forms of Alopecia.
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Parikh AK, Tan IJ, Wolfe SM, and Cohen BA
- Abstract
Alopecia encompasses diverse conditions that vary by etiology, progression, and clinical presentation, including androgenetic alopecia, alopecia areata, telogen effluvium, and scarring alopecias such as lichen planopilaris and central centrifugal cicatricial alopecia. Managing these conditions requires tailored therapeutic approaches, with topical treatments emerging as effective first-line interventions. This literature review examines topical therapies across alopecia types, assessing mechanisms of action, clinical efficacy, and safety profiles to guide evidence-based clinical practice. Methods involved a comprehensive search across PubMed, SCOPUS, and Web of Science databases, focusing on clinical research published within the past five years. Articles were screened based on relevance to alopecia management, excluding abstracts, non-English studies, and ongoing research. Topics covered include commonly used agents such as minoxidil, corticosteroids, and emerging options like Janus kinase (JAK) inhibitors. Topicals for trichotillomania, such as capsaicin and numbing creams, are highlighted for their behavioral conditioning potential, while treatments like minoxidil and adenosine are explored for telogen effluvium. Findings indicate that topicals provide symptom relief, promote hair regrowth, and often serve as adjuncts to systemic therapies. Minoxidil and corticosteroids demonstrate efficacy in multiple alopecia types, while JAK inhibitors show promise in alopecia areata. This review underscores the value of topical treatments in alopecia management and highlights areas for future research, advocating for individualized approaches to enhance therapeutic outcomes in patients experiencing hair loss.
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- 2024
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115. Melanoma Metabolism: Molecular Mechanisms and Therapeutic Implications in Cutaneous Oncology.
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Tan IJ, Parikh AK, and Cohen BA
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- Humans, Mitochondria metabolism, Epigenesis, Genetic, Lipid Metabolism, Warburg Effect, Oncologic, Melanoma metabolism, Melanoma pathology, Melanoma drug therapy, Melanoma genetics, Skin Neoplasms metabolism, Skin Neoplasms pathology, Skin Neoplasms drug therapy, Tumor Microenvironment
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Background: Melanoma, a highly aggressive skin cancer, is characterized by rapid progression and a high metastatic potential, presenting significant challenges in clinical oncology. A critical aspect of melanoma biology is its metabolic reprogramming, which supports tumor growth, survival, and therapeutic resistance., Objective: This review aims to explore the key molecular mechanisms driving metabolic alterations in melanoma and their implications for developing therapeutic strategies., Methods: A Pubmed search was conducted to analyze literature discussing key mechanisms of the Warburg effect, mitochondrial dysfunction, enhanced lipid metabolism, epigenetic modifications, and the tumor microenvironment., Results: Metabolic reprogramming supports melanoma growth, proliferation, and survival. Understanding these complex metabolic dynamics provides valuable insights for developing targeted therapeutic strategies., Conclusion: Potential therapeutic interventions aimed at disrupting melanoma metabolism highlight the promise of precision medicine in improving treatment outcomes in cutaneous oncology. By targeting metabolic vulnerabilities, novel treatment approaches could significantly enhance the clinical management and prognosis of melanoma., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)
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- 2024
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116. Mutational scanning of CRX classifies clinical variants and reveals biochemical properties of the transcriptional effector domain.
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Shepherdson JL, Granas DM, Li J, Shariff Z, Plassmeyer SP, Holehouse AS, White MA, and Cohen BA
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- Humans, Protein Domains, Amino Acid Substitution, DNA Mutational Analysis, Mutation, Genetic Variation, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Trans-Activators genetics, Trans-Activators metabolism
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The transcription factor (TF) cone-rod homeobox (CRX) is essential for the differentiation and maintenance of photoreceptor cell identity. Several human CRX variants cause degenerative retinopathies, but most are variants of uncertain significance. We performed a deep mutational scan (DMS) of nearly all possible single amino acid substitutions in CRX using a cell-based transcriptional reporter assay, curating a high-confidence list of nearly 2000 variants with altered transcriptional activity. In the structured homeodomain, activity scores closely aligned to a predicted structure and demonstrated position-specific constraints on amino acid substitution. In contrast, the intrinsically disordered transcriptional effector domain displayed a qualitatively different pattern of substitution effects, following compositional constraints without specific residue position requirements in the peptide chain. These compositional constraints were consistent with the acidic exposure model of transcriptional activation. We evaluated the performance of the DMS assay as a clinical variant classification tool using gold-standard classified human variants from ClinVar, identifying pathogenic variants with high specificity and moderate sensitivity. That this performance could be achieved using a synthetic reporter assay in a foreign cell type, even for a highly cell type-specific TF like CRX, suggests that this approach shows promise for DMS of other TFs that function in cell types that are not easily accessible. Together, the results of the CRX DMS identify molecular features of the CRX effector domain and demonstrate utility for integration into the clinical variant classification pipeline., (© 2024 Shepherdson et al.; Published by Cold Spring Harbor Laboratory Press.)
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- 2024
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117. Occupational Exposures and Skin Cancer: A Brief Report.
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Parikh AK, Tan IJ, and Cohen BA
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- Humans, Female, Male, Middle Aged, Occupational Diseases, Adult, Risk Factors, Skin Neoplasms etiology, Skin Neoplasms epidemiology, Occupational Exposure adverse effects
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- 2024
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118. Massively parallel characterization of insulator activity across the genome.
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Hong CKY, Wu Y, Erickson AA, Li J, Federico AJ, and Cohen BA
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- Animals, Genome genetics, Heterochromatin genetics, Heterochromatin metabolism, Genomics methods, Mice, High-Throughput Nucleotide Sequencing methods, Insulator Elements genetics, Enhancer Elements, Genetic genetics
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A key question in regulatory genomics is whether cis-regulatory elements (CREs) are modular elements that can function anywhere in the genome, or whether they are adapted to certain genomic locations. To distinguish between these possibilities we develop MPIRE (Massively Parallel Integrated Regulatory Elements), a technology for recurrently assaying CREs at thousands of defined locations across the genome in parallel. MPIRE allows us to separate the intrinsic activity of CREs from the effects of their genomic environments. We apply MPIRE to assay three insulator sequences at thousands of genomic locations and find that each insulator functions in locations with distinguishable properties. All three insulators can block enhancers, but each insulator blocks specific enhancers at specific locations. However, only ALOXE3 appears to block heterochromatin silencing. We conclude that insulator function is highly context dependent and that MPIRE is a robust method for revealing the context dependencies of CREs., (© 2024. The Author(s).)
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- 2024
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119. Environmental exposures and chronic inflammatory dermatoses: Preventive and therapeutic strategies.
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Tan IJ, Parikh AK, and Cohen BA
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- Humans, Chronic Disease, Dermatitis prevention & control, Dermatitis etiology, Environmental Exposure adverse effects
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- 2024
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120. Updates on Topical Dyad and Triple Combination Therapies Approved for Acne Vulgaris.
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Podwojniak A, Tan IJ, Sauer J, Parikh A, Cohen BA, and Heath C
- Abstract
Acne vulgaris is a multifaceted disease characterized by inflammatory and noninflammatory lesions. Topical combination therapies offer a multifaceted approach to acne treatment, with synergistic effects and a broad spectrum of action against multiple factors in acne pathogenesis in one single formulation. Clindamycin phosphate/benzoyl peroxide/adapalene, a combination therapy consisting of clindamycin phosphate 1.2%, benzoyl peroxide (BPO) 3.1%, and adapalene 0.15%, is a novel treatment, the only FDA-approved triple combination drug that offers effective treatment of acne vulgaris. This review aims to provide information on clindamycin phosphate/benzoyl peroxide/adapalene and review the literature on combination topical acne medications approved in the United States. This search was conducted on topical combination therapies for acne, their efficacy, adverse effects, and impacts on quality of life with a specific focus on the newly approved clindamycin phosphate/benzoyl peroxide/adapalene and its sub-component dyads, along with other combinations. PubMed, SCOPUS, Embase, Cochrane, and Web of Science databases were searched for publications in 2018-2023. Primary sources were given priority, and secondary sources such as other reviews were considered to supplement any missing information. It was found that various topical dyad and triad combinations exist for acne vulgaris, including adapalene/BPO, tazarotene/clindamycin, clindamycin/BPO, adapalene/clindamycin, topical tretinoin/azelaic acid, topical tretinoin/BPO, and clindamycin phosphate/benzoyl peroxide/adapalene. Dyad and triple combinations represent a promising, convenient solution for acne management, potentially improving patient adherence due to its single formulation. Clindamycin phosphate/benzoyl peroxide/adapalene exhibited significantly high efficacy in treating both inflammatory and noninflammatory lesions, a minimal side effect profile, although no significant changes in quality-of-life measures. Further research is indicated to assess its long-term efficacy and impact on other acne metrics such as cost, scarring, psychosocial implications, and impact on diverse patient populations., Competing Interests: Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Podwojniak et al.)
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- 2024
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121. Effect of genomic and cellular environments on gene expression noise.
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Hong CKY, Ramu A, Zhao S, and Cohen BA
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- Humans, Genes, Reporter, Transcriptome, Genomics methods, Single-Cell Analysis
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Background: Individual cells from isogenic populations often display large cell-to-cell differences in gene expression. This "noise" in expression derives from several sources, including the genomic and cellular environment in which a gene resides. Large-scale maps of genomic environments have revealed the effects of epigenetic modifications and transcription factor occupancy on mean expression levels, but leveraging such maps to explain expression noise will require new methods to assay how expression noise changes at locations across the genome., Results: To address this gap, we present Single-cell Analysis of Reporter Gene Expression Noise and Transcriptome (SARGENT), a method that simultaneously measures the noisiness of reporter genes integrated throughout the genome and the global mRNA profiles of individual reporter-gene-containing cells. Using SARGENT, we perform the first comprehensive genome-wide survey of how genomic locations impact gene expression noise. We find that the mean and noise of expression correlate with different histone modifications. We quantify the intrinsic and extrinsic components of reporter gene noise and, using the associated mRNA profiles, assign the extrinsic component to differences between the CD24+ "stem-like" substate and the more "differentiated" substate. SARGENT also reveals the effects of transgene integrations on endogenous gene expression, which will help guide the search for "safe-harbor" loci., Conclusions: Taken together, we show that SARGENT is a powerful tool to measure both the mean and noise of gene expression at locations across the genome and that the data generatd by SARGENT reveals important insights into the regulation of gene expression noise genome-wide., (© 2024. The Author(s).)
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- 2024
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122. Sphingosine 1-phosphate receptor modulators in multiple sclerosis treatment: A practical review.
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Coyle PK, Freedman MS, Cohen BA, Cree BAC, and Markowitz CE
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- United States, Humans, Sphingosine-1-Phosphate Receptors therapeutic use, Fingolimod Hydrochloride adverse effects, Administration, Oral, Multiple Sclerosis drug therapy, Sphingosine 1 Phosphate Receptor Modulators adverse effects
- Abstract
Four sphingosine 1-phosphate (S1P) receptor modulators (fingolimod, ozanimod, ponesimod, and siponimod) are approved by the US Food and Drug Administration for the treatment of multiple sclerosis. This review summarizes efficacy and safety data on these S1P receptor modulators, with an emphasis on similarities and differences. Efficacy data from the pivotal clinical trials are generally similar for the four agents. However, because no head-to-head clinical studies were conducted, direct efficacy comparisons cannot be made. Based on the adverse event profile of S1P receptor modulators, continued and regular monitoring of patients during treatment will be instructive. Notably, the authors recommend paying attention to the cardiac monitoring guidelines for these drugs, and when indicated screening for macular edema and cutaneous malignancies before starting treatment. To obtain the best outcome, clinicians should choose the drug based on disease type, history, and concomitant medications for each patient. Real-world data should help to determine whether there are meaningful differences in efficacy or side effects between these agents., (© 2024 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)
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- 2024
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123. Precision Dermatology: A Review of Molecular Biomarkers and Personalized Therapies.
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Tan IJ, Podwojniak A, Parikh A, and Cohen BA
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The evolution of personalized medicine in dermatology signifies a transformative shift towards individualized treatments, driven by the integration of biomarkers. These molecular indicators serve beyond diagnostics, offering insights into disease staging, prognosis, and therapeutic monitoring. Specific criteria guide biomarker selection, ensuring attributes like specificity, sensitivity, cost feasibility, stability, rapid detection, and reproducibility. This literature review, based on data from PubMed, SCOPUS, and Web of Science, explores biomarkers in Hidradenitis Suppurativa (HS), Psoriasis, Atopic Dermatitis (AD), Alopecia Areata (AA), Vitiligo, and Chronic Spontaneous Urticaria (CSU). In HS, TNF-α, IL-1β, and MMPs serve as biomarkers, influencing targeted therapies like adalimumab and anakinra. Psoriasis involves biomarkers such as TNF-α, IL-23, and HLA genes, shaping treatments like IL23 and IL17 inhibitors. AD biomarkers include ECP, IL-4, IL-13, guiding therapies like dupilumab and tralokinumab. For AA, lipocalin-2, cytokines, and genetic polymorphisms inform JAK inhibitors' use. Vitiligo biomarkers range from cytokines to genetic markers like TYR, TYRP1, guiding treatments like JAK inhibitors. CSU biomarkers encompass IgE, cytokines, and autologous serum tests, influencing therapies like omalizumab and cyclosporine. Comparing conditions, common proinflammatory markers reveal limited specificity. While some biomarkers aid diagnosis and standard treatments, others hold more scientific than clinical value. Precision medicine, driven by biomarkers, has shown success in skin malignancies. Future directions involve AI-powered algorithms, nanotechnology, and multi-omics integration for personalized dermatological care.
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- 2024
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124. Pathogenic variants in CRX have distinct cis -regulatory effects on enhancers and silencers in photoreceptors.
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Shepherdson JL, Friedman RZ, Zheng Y, Sun C, Oh IY, Granas DM, Cohen BA, Chen S, and White MA
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- Animals, Humans, Mice, Regulatory Sequences, Nucleic Acid, Retina metabolism, Retinal Cone Photoreceptor Cells metabolism, Transcription Factors genetics, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Trans-Activators genetics, Trans-Activators metabolism
- Abstract
Dozens of variants in the gene for the homeodomain transcription factor (TF) cone-rod homeobox ( CRX ) are linked with human blinding diseases that vary in their severity and age of onset. How different variants in this single TF alter its function in ways that lead to a range of phenotypes is unclear. We characterized the effects of human disease-causing variants on CRX cis -regulatory function by deploying massively parallel reporter assays (MPRAs) in mouse retina explants carrying knock-ins of two variants, one in the DNA-binding domain (p.R90W) and the other in the transcriptional effector domain (p.E168d2). The degree of reporter gene dysregulation in these mutant Crx retinas corresponds with their phenotypic severity. The two variants affect similar sets of enhancers, and p.E168d2 has distinct effects on silencers. Cis -regulatory elements (CREs) near cone photoreceptor genes are enriched for silencers that are derepressed in the presence of p.E168d2. Chromatin environments of CRX-bound loci are partially predictive of episomal MPRA activity, and distal elements whose accessibility increases later in retinal development are enriched for CREs with silencer activity. We identified a set of potentially pleiotropic regulatory elements that convert from silencers to enhancers in retinas that lack a functional CRX effector domain. Our findings show that phenotypically distinct variants in different domains of CRX have partially overlapping effects on its cis -regulatory function, leading to misregulation of similar sets of enhancers while having a qualitatively different impact on silencers., (© 2024 Shepherdson et al.; Published by Cold Spring Harbor Laboratory Press.)
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- 2024
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125. Transcription factor interactions explain the context-dependent activity of CRX binding sites.
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Loell KJ, Friedman RZ, Myers CA, Corbo JC, Cohen BA, and White MA
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- Homeodomain Proteins genetics, Gene Expression Regulation, Binding Sites genetics, Retina, Transcription Factors metabolism, Trans-Activators metabolism
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The effects of transcription factor binding sites (TFBSs) on the activity of a cis-regulatory element (CRE) depend on the local sequence context. In rod photoreceptors, binding sites for the transcription factor (TF) Cone-rod homeobox (CRX) occur in both enhancers and silencers, but the sequence context that determines whether CRX binding sites contribute to activation or repression of transcription is not understood. To investigate the context-dependent activity of CRX sites, we fit neural network-based models to the activities of synthetic CREs composed of photoreceptor TFBSs. The models revealed that CRX binding sites consistently make positive, independent contributions to CRE activity, while negative homotypic interactions between sites cause CREs composed of multiple CRX sites to function as silencers. The effects of negative homotypic interactions can be overcome by the presence of other TFBSs that either interact cooperatively with CRX sites or make independent positive contributions to activity. The context-dependent activity of CRX sites is thus determined by the balance between positive heterotypic interactions, independent contributions of TFBSs, and negative homotypic interactions. Our findings explain observed patterns of activity among genomic CRX-bound enhancers and silencers, and suggest that enhancers may require diverse TFBSs to overcome negative homotypic interactions between TFBSs., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: BAC is on the scientific advisory board of Patch Biosciences. Neither any reagent nor any funding from this organizations was used in this study. Other co-authors have no competing interests to declare., (Copyright: © 2024 Loell et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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126. Evaluating the clinical efficacy of pulsed dye laser with sirolimus for treatment of capillary malformations: A systematic review.
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Tan IJ, Truong TM, Pathak GN, Mehdikhani S, Rao B, and Cohen BA
- Abstract
Port-wine stains (PWS) are capillary vascular anomalies that are often treated with pulsed-dye laser (PDL). Revascularization limits persistent clearance; however, the anti-angiogenic effects of sirolimus (SIRO) may inhibit revascularization. This review aims to determine differences in PWS outcomes when treated with PDL monotherapy or in combination with SIRO. A systematic review was conducted using PubMed, Cochrane, and Embase databases. The following search terms were used: 'port wine stain PDL SIRO', 'port wine stain PDL', and 'port wine stain PDL and topical treatment' with (MeSH) and (Title/Abstract) limits. The search was limited to the English language and human-subject studies conducted between 1 January 2000 and 1 June 2023. Inclusion criteria included studies evaluating SIRO as an adjunct to PDL in patients with PWS. Data extraction and quality assessment were performed by two independent reviewers. A total of nine studies met the inclusion criteria, which included randomized controlled trials (3), case series (2), case reports (3), and a prospective intrapatient study (1), which represented a total of 58 patients. Five studies showed improvement of a measured post-treatment PDL parameter including shortening treatment time and less frequent dosing. A subset of studies (4/9) which did not demonstrate significant clinical improvements exhibited significant photographic evidence of improvement. Heterogeneity among the studies highlights the need for further research and standardization. While adjunctive SIRO shows promise, larger studies and comprehensive evaluation methods are required to establish conclusive safety and efficacy guidelines to shape clinical decision-making., Competing Interests: Dr. Rao is a speaker for Incyte. All other authors have no disclosures., (© 2024 The Authors. Skin Health and Disease published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists.)
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- 2024
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127. Pathogenic variants in Crx have distinct cis-regulatory effects on enhancers and silencers in photoreceptors.
- Author
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Shepherdson JL, Friedman RZ, Zheng Y, Sun C, Oh IY, Granas DM, Cohen BA, Chen S, and White MA
- Abstract
Dozens of variants in the photoreceptor-specific transcription factor (TF) CRX are linked with human blinding diseases that vary in their severity and age of onset. It is unclear how different variants in this single TF alter its function in ways that lead to a range of phenotypes. We examined the effects of human disease-causing variants on CRX cis -regulatory function by deploying massively parallel reporter assays (MPRAs) in live mouse retinas carrying knock-ins of two variants, one in the DNA binding domain (p.R90W) and the other in the transcriptional effector domain (p.E168d2). The degree of reporter gene dysregulation caused by the variants corresponds with their phenotypic severity. The two variants affect similar sets of enhancers, while p.E168d2 has stronger effects on silencers. Cis -regulatory elements (CREs) near cone photoreceptor genes are enriched for silencers that are de-repressed in the presence of p.E168d2. Chromatin environments of CRX-bound loci were partially predictive of episomal MPRA activity, and silencers were notably enriched among distal elements whose accessibility increases later in retinal development. We identified a set of potentially pleiotropic regulatory elements that convert from silencers to enhancers in retinas that lack a functional CRX effector domain. Our findings show that phenotypically distinct variants in different domains of CRX have partially overlapping effects on its cis -regulatory function, leading to misregulation of similar sets of enhancers, while having a qualitatively different impact on silencers., Competing Interests: Competing Interest Statement B.A.C is on the scientific advisory board of Patch Biosciences. The authors declare no other competing interests.
- Published
- 2023
- Full Text
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128. A Cre-dependent massively parallel reporter assay allows for cell-type specific assessment of the functional effects of non-coding elements in vivo.
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Lagunas T Jr, Plassmeyer SP, Fischer AD, Friedman RZ, Rieger MA, Selmanovic D, Sarafinovska S, Sol YK, Kasper MJ, Fass SB, Aguilar Lucero AF, An JY, Sanders SJ, Cohen BA, and Dougherty JD
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- Animals, Humans, Mice, 3' Untranslated Regions, Cerebral Cortex, Medium Spiny Neurons, Regulatory Sequences, Nucleic Acid, Oligonucleotide Array Sequence Analysis methods
- Abstract
The function of regulatory elements is highly dependent on the cellular context, and thus for understanding the function of elements associated with psychiatric diseases these would ideally be studied in neurons in a living brain. Massively Parallel Reporter Assays (MPRAs) are molecular genetic tools that enable functional screening of hundreds of predefined sequences in a single experiment. These assays have not yet been adapted to query specific cell types in vivo in a complex tissue like the mouse brain. Here, using a test-case 3'UTR MPRA library with genomic elements containing variants from autism patients, we developed a method to achieve reproducible measurements of element effects in vivo in a cell type-specific manner, using excitatory cortical neurons and striatal medium spiny neurons as test cases. This targeted technique should enable robust, functional annotation of genetic elements in the cellular contexts most relevant to psychiatric disease., (© 2023. The Author(s).)
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- 2023
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129. Differential Diagnosis of Tumor-like Brain Lesions.
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Perez Giraldo GS, Singer L, Cao T, Jamshidi P, Dixit K, Kontzialis M, Castellani R, Pytel P, Anadani N, Bevan CJ, Grebenciucova E, Balabanov R, Cohen BA, and Graham EL
- Abstract
Purpose of Review: Tumor-like brain lesions are rare and commonly suggest a neoplastic etiology. Failure to rapidly identify non-neoplastic causes can lead to increased morbidity and mortality. In this review, we describe 10 patients who presented with atypical, non-neoplastic tumor-like brain lesions in which brain biopsy was essential for a correct diagnosis and treatment., Recent Findings: There has been increasing recognition of autoimmune conditions affecting the nervous system, and many of those diseases can cause tumor-like brain lesions. Currently available reports of non-neoplastic tumor-like brain lesions are scarce. Most case series focus on tumefactive demyelinating lesions, and a comprehensive review including other neuroimmunological conditions such as CNS vasculitis, neurosarcoidosis, histiocytic and infectious etiologies is lacking., Summary: We review the literature on tumor-like brain lesions intending to increase the awareness and differential diagnosis of non-neoplastic brain tumor mimics. We advocate for earlier brain biopsies, which, in our case series, significantly changed diagnosis, management, and outcomes., Competing Interests: G.S. Perez reports no disclosures relevant to the manuscript; L. Singer reports no disclosures relevant to the manuscript; T. Cao reports no disclosures relevant to the manuscript; P. Jamshidi reports no disclosures relevant to the manuscript; K. Dixit reports no disclosures relevant to the manuscript; M. Kontzialis reports no disclosures relevant to the manuscript; R. Castellani reports no disclosures relevant to the manuscript; P. Pytel reports no disclosures relevant to the manuscript; N. Anadani reports no disclosures relevant to the manuscript; C. Bevan has participated in an ad board for Genentech; E. Grebenciucova reports no disclosures relevant to the manuscript; R. Balabanov received honoraria from Biogen, Sanofi, Alexion, and Teva Pharmaceutical and research support from the National Multiple Sclerosis Society, National Institute of Health, Nextcure, and Biogen; B. Cohen reports no disclosures relevant to the manuscript. E. Graham received consulting and advisory board fees from Novartis, Atara Biotherapeutics, Tavistock Life Sciences, Horizon Therapeutics, Roche Genentech. She receives research support from F. Hoffman-La Roche Ltd. She received compensation for question writing from ACP MKSAP. Full disclosure form information provided by the authors is available with the full text of this article at Neurology.org/cp., (© 2023 American Academy of Neurology.)
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- 2023
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130. Active learning of enhancer and silencer regulatory grammar in photoreceptors.
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Friedman RZ, Ramu A, Lichtarge S, Myers CA, Granas DM, Gause M, Corbo JC, Cohen BA, and White MA
- Abstract
Cis -regulatory elements (CREs) direct gene expression in health and disease, and models that can accurately predict their activities from DNA sequences are crucial for biomedicine. Deep learning represents one emerging strategy to model the regulatory grammar that relates CRE sequence to function. However, these models require training data on a scale that exceeds the number of CREs in the genome. We address this problem using active machine learning to iteratively train models on multiple rounds of synthetic DNA sequences assayed in live mammalian retinas. During each round of training the model actively selects sequence perturbations to assay, thereby efficiently generating informative training data. We iteratively trained a model that predicts the activities of sequences containing binding motifs for the photoreceptor transcription factor Cone-rod homeobox (CRX) using an order of magnitude less training data than current approaches. The model's internal confidence estimates of its predictions are reliable guides for designing sequences with high activity. The model correctly identified critical sequence differences between active and inactive sequences with nearly identical transcription factor binding sites, and revealed order and spacing preferences for combinations of motifs. Our results establish active learning as an effective method to train accurate deep learning models of cis -regulatory function after exhausting naturally occurring training examples in the genome., Competing Interests: COMPETING INTERESTS B.A.C. is on the scientific advisory board of Patch Biosciences. The remaining authors declare no competing interests.
- Published
- 2023
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131. Transcription factor fluctuations underlie cell-to-cell variability in a signaling pathway response.
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Ramu A and Cohen BA
- Subjects
- Animals, Mice, NIH 3T3 Cells, Gene Expression Regulation, Signal Transduction, Transcription Factors genetics, Transcription Factors metabolism, Hedgehog Proteins genetics, Hedgehog Proteins metabolism
- Abstract
Stochastic differences among clonal cells can initiate cell fate decisions in development or cause cell-to-cell differences in the responses to drugs or extracellular ligands. One hypothesis is that some of this phenotypic variability is caused by stochastic fluctuations in the activities of transcription factors (TFs). We tested this hypothesis in NIH3T3-CG cells using the response to Hedgehog signaling as a model cellular response. Here, we present evidence for the existence of distinct fast- and slow-responding substates in NIH3T3-CG cells. These two substates have distinct expression profiles, and fluctuations in the Prrx1 TF underlie some of the differences in expression and responsiveness between fast and slow cells. Our results show that fluctuations in TFs can contribute to cell-to-cell differences in Hedgehog signaling., Competing Interests: Conflicts of interest statement Barak A. Cohen is on the scientific advisory board of Patch Biosciences., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Genetics Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2023
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132. The origins and functional effects of postzygotic mutations throughout the human life span.
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Rockweiler NB, Ramu A, Nagirnaja L, Wong WH, Noordam MJ, Drubin CW, Huang N, Miller B, Todres EZ, Vigh-Conrad KA, Zito A, Small KS, Ardlie KG, Cohen BA, and Conrad DF
- Subjects
- Female, Humans, Mutation, Phylogeny, RNA-Seq, Longevity genetics, Zygote, DNA Mutational Analysis
- Abstract
Postzygotic mutations (PZMs) begin to accrue in the human genome immediately after fertilization, but how and when PZMs affect development and lifetime health remain unclear. To study the origins and functional consequences of PZMs, we generated a multitissue atlas of PZMs spanning 54 tissue and cell types from 948 donors. Nearly half the variation in mutation burden among tissue samples can be explained by measured technical and biological effects, and 9% can be attributed to donor-specific effects. Through phylogenetic reconstruction of PZMs, we found that their type and predicted functional impact vary during prenatal development, across tissues, and through the germ cell life cycle. Thus, methods for interpreting effects across the body and the life span are needed to fully understand the consequences of genetic variants.
- Published
- 2023
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133. Clinic-Based Interventions to Support Social Participation for Autistic Children and Adolescents (2013-2021).
- Author
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Little LM, Cohen SR, Tomchek SD, Baker A, Wallisch A, and Dean E
- Subjects
- Adolescent, Child, Humans, Social Participation, Systematic Reviews as Topic, Autistic Disorder, Occupational Therapy
- Abstract
Systematic review briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each systematic review brief summarizes the evidence on a theme related to a systematic review topic. This systematic review brief presents findings from clinic-based studies to support social participation for autistic1 children and adolescents (birth to 18 yr)., (Copyright © 2023 by the American Occupational Therapy Association, Inc.)
- Published
- 2023
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134. Mucocutaneous manifestations of congenital syphilis in the neonate: A review of a surging disease.
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Newton J, Silence C, Boetes J, and Cohen BA
- Subjects
- Pregnancy, Female, Infant, Newborn, Humans, Treponema pallidum, Public Health, Syphilis, Congenital diagnosis, Syphilis, Congenital drug therapy, Syphilis diagnosis, Syphilis drug therapy
- Abstract
Syphilis is an infection caused by Treponema pallidum. It is most commonly acquired through sexual transmission, although it can also be transmitted vertically across the placenta, resulting in congenital syphilis. Even with improved public health measures, testing, and treatment capabilities, primary, secondary, and congenital syphilis have all surged since 2012. Given this marked increase in both incidence and prevalence, here we present a comprehensive review of the clinical presentation, treatment, and management of congenital syphilis, with particular consideration given to the mucocutaneous manifestations of the disease in neonates., (© 2022 Wiley Periodicals LLC.)
- Published
- 2023
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135. Interventions to Support Social Participation for Autistic Children and Adolescents in Schools (2013-2021).
- Author
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Little LM, Cohen SR, Tomchek SD, Baker A, Wallisch A, and Dean E
- Subjects
- Adolescent, Child, Humans, Schools, Social Participation, Systematic Reviews as Topic, Autistic Disorder, Occupational Therapy
- Abstract
Systematic review briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each systematic review brief summarizes the evidence on a theme related to a systematic review topic. This systematic review brief presents findings to support social participation in school contexts for autistic1 children and adolescents (birth to 18 yr)., (Copyright © 2023 by the American Occupational Therapy Association, Inc.)
- Published
- 2023
- Full Text
- View/download PDF
136. Interventions to Support Participation in Play for Autistic Children and Youth (Dates of Review: 2013-2021).
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Little LM, Cohen SR, Tomchek S, Baker A, Wallisch A, and Dean E
- Abstract
Systematic Review Briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each systematic review brief summarizes the evidence on a theme related to a systematic review topic. This systematic review brief presents findings to support participation in play for autistic1 children and adolescents (birth to 18 yr)., (Copyright © 2023 by the American Occupational Therapy Association, Inc.)
- Published
- 2023
- Full Text
- View/download PDF
137. Interventions to Support Social Participation for Autistic Children and Adolescents in Homes and Communities (2013-2021).
- Author
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Little LM, Cohen SR, Tomchek SD, Baker A, Wallisch A, and Dean E
- Subjects
- Adolescent, Child, Humans, Social Participation, Systematic Reviews as Topic, Autistic Disorder, Occupational Therapy
- Abstract
Systematic review briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association's Evidence-Based Practice Program. Each systematic review brief summarizes the evidence on a theme related to a systematic review topic. This systematic review brief presents findings to support social participation for autistic1 children and adolescents (birth to 18 yr) in homes and communities., (Copyright © 2023 by the American Occupational Therapy Association, Inc.)
- Published
- 2023
- Full Text
- View/download PDF
138. A single-cell massively parallel reporter assay detects cell-type-specific gene regulation.
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Zhao S, Hong CKY, Myers CA, Granas DM, White MA, Corbo JC, and Cohen BA
- Subjects
- Animals, Humans, Mice, Gene Library, Promoter Regions, Genetic, Retina metabolism, Genes, Reporter genetics, HEK293 Cells
- Abstract
Massively parallel reporter gene assays are key tools in regulatory genomics but cannot be used to identify cell-type-specific regulatory elements without performing assays serially across different cell types. To address this problem, we developed a single-cell massively parallel reporter assay (scMPRA) to measure the activity of libraries of cis-regulatory sequences (CRSs) across multiple cell types simultaneously. We assayed a library of core promoters in a mixture of HEK293 and K562 cells and showed that scMPRA is a reproducible, highly parallel, single-cell reporter gene assay that detects cell-type-specific cis-regulatory activity. We then measured a library of promoter variants across multiple cell types in live mouse retinas and showed that subtle genetic variants can produce cell-type-specific effects on cis-regulatory activity. We anticipate that scMPRA will be widely applicable for studying the role of CRSs across diverse cell types., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)
- Published
- 2023
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139. Testing Rover Science Protocols to Identify Possible Biosignatures on Mars: Achieving Sampling Goals Under a Highly Constrained Time Line.
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Yingst RA, Bartley JK, Chidsey TJ Jr, Cohen BA, Curran N, Hynek BM, Kah LC, Minitti ME, Vanden Berg MD, Williams RME, Gemperline J, Lotto M, Black S, Bartley BC, and Pearson T
- Subjects
- Extraterrestrial Environment, Goals, Strategic Planning, Exobiology methods, Mars
- Abstract
At a Mars analog site in Utah, we tested two science operation methods for data acquisition and decision-making protocols: a scenario where the tactical day is preplanned, but major adjustments may still be made before plan delivery; and a scenario in which the sol path must largely be planned before a given tactical planning day and very few adjustments to the plan may be made. The goal was to provide field-tested insight into operations planning for rover missions where science operations must facilitate the efficient choice of sampling locations at a site relevant to searching for habitability and biosignatures. Results of the test indicate that preplanning sol paths did not result in a sol cost savings nor did it improve science return or optimal biologically relevant sample collection. In addition because facies variations in an environment can be subtle and evident only at scales below orbital resolution, acquiring systematic observations is crucial. We also noted that while spectral data provided insight into the chemical components as a whole at this site, they did not provide a guide to targets for which the traverse should be altered. Finally, strategic science planning must include a special effort to account for terrain.
- Published
- 2022
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140. A quantitative metric of pioneer activity reveals that HNF4A has stronger in vivo pioneer activity than FOXA1.
- Author
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Hansen JL and Cohen BA
- Subjects
- Binding Sites, Genome, Genomics, DNA metabolism, Doxycycline
- Abstract
Background: We and others have suggested that pioneer activity - a transcription factor's (TF's) ability to bind and open inaccessible loci - is not a qualitative trait limited to a select class of pioneer TFs. We hypothesize that most TFs display pioneering activity that depends on the TF concentration and the motif content at their target loci., Results: Here, we present a quantitative in vivo measure of pioneer activity that captures the relative difference in a TF's ability to bind accessible versus inaccessible DNA. The metric is based on experiments that use CUT&Tag to measure the binding of doxycycline-inducible TFs. For each location across the genome, we determine the concentration of doxycycline required for a TF to reach half-maximal occupancy; lower concentrations reflect higher affinity. We propose that the relative difference in a TF's affinity between ATAC-seq labeled accessible and inaccessible binding sites is a measure of its pioneer activity. We estimate binding affinities at tens of thousands of genomic loci for the endodermal TFs FOXA1 and HNF4A and show that HNF4A has stronger pioneer activity than FOXA1. We show that both FOXA1 and HNF4A display higher binding affinity at inaccessible sites with more copies of their respective motifs. The quantitative analysis of binding suggests different modes of binding for FOXA1, including an anti-cooperative mode of binding at certain accessible loci., Conclusions: Our results suggest that relative binding affinities are reasonable measures of pioneer activity and support the model wherein most TFs have some degree of context-dependent pioneer activity., (© 2022. The Author(s).)
- Published
- 2022
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141. Functional characterization of enhancer activity during a long terminal repeat's evolution.
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Du AY, Zhuo X, Sundaram V, Jensen NO, Chaudhari HG, Saccone NL, Cohen BA, and Wang T
- Subjects
- Humans, DNA Transposable Elements genetics, Genome, Human, Terminal Repeat Sequences genetics, Evolution, Molecular, Enhancer Elements, Genetic, Transcription Factor AP-1 genetics, Regulatory Sequences, Nucleic Acid
- Abstract
Many transposable elements (TEs) contain transcription factor binding sites and are implicated as potential regulatory elements. However, TEs are rarely functionally tested for regulatory activity, which in turn limits our understanding of how TE regulatory activity has evolved. We systematically tested the human LTR18A subfamily for regulatory activity using massively parallel reporter assay (MPRA) and found AP-1- and CEBP-related binding motifs as drivers of enhancer activity. Functional analysis of evolutionarily reconstructed ancestral sequences revealed that LTR18A elements have generally lost regulatory activity over time through sequence changes, with the largest effects occurring owing to mutations in the AP-1 and CEBP motifs. We observed that the two motifs are conserved at higher rates than expected based on neutral evolution. Finally, we identified LTR18A elements as potential enhancers in the human genome, primarily in epithelial cells. Together, our results provide a model for the origin, evolution, and co-option of TE-derived regulatory elements., (© 2022 Du et al.; Published by Cold Spring Harbor Laboratory Press.)
- Published
- 2022
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142. Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars.
- Author
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Farley KA, Stack KM, Shuster DL, Horgan BHN, Hurowitz JA, Tarnas JD, Simon JI, Sun VZ, Scheller EL, Moore KR, McLennan SM, Vasconcelos PM, Wiens RC, Treiman AH, Mayhew LE, Beyssac O, Kizovski TV, Tosca NJ, Williford KH, Crumpler LS, Beegle LW, Bell JF 3rd, Ehlmann BL, Liu Y, Maki JN, Schmidt ME, Allwood AC, Amundsen HEF, Bhartia R, Bosak T, Brown AJ, Clark BC, Cousin A, Forni O, Gabriel TSJ, Goreva Y, Gupta S, Hamran SE, Herd CDK, Hickman-Lewis K, Johnson JR, Kah LC, Kelemen PB, Kinch KB, Mandon L, Mangold N, Quantin-Nataf C, Rice MS, Russell PS, Sharma S, Siljeström S, Steele A, Sullivan R, Wadhwa M, Weiss BP, Williams AJ, Wogsland BV, Willis PA, Acosta-Maeda TA, Beck P, Benzerara K, Bernard S, Burton AS, Cardarelli EL, Chide B, Clavé E, Cloutis EA, Cohen BA, Czaja AD, Debaille V, Dehouck E, Fairén AG, Flannery DT, Fleron SZ, Fouchet T, Frydenvang J, Garczynski BJ, Gibbons EF, Hausrath EM, Hayes AG, Henneke J, Jørgensen JL, Kelly EM, Lasue J, Le Mouélic S, Madariaga JM, Maurice S, Merusi M, Meslin PY, Milkovich SM, Million CC, Moeller RC, Núñez JI, Ollila AM, Paar G, Paige DA, Pedersen DAK, Pilleri P, Pilorget C, Pinet PC, Rice JW Jr, Royer C, Sautter V, Schulte M, Sephton MA, Sharma SK, Sholes SF, Spanovich N, St Clair M, Tate CD, Uckert K, VanBommel SJ, Yanchilina AG, and Zorzano MP
- Abstract
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater's sedimentary delta, finding that the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Magnesium-iron carbonates along grain boundaries indicate reactions with carbon dioxide-rich water under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks have been stored aboard Perseverance for potential return to Earth.
- Published
- 2022
- Full Text
- View/download PDF
143. Directed mutational scanning reveals a balance between acidic and hydrophobic residues in strong human activation domains.
- Author
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Staller MV, Ramirez E, Kotha SR, Holehouse AS, Pappu RV, and Cohen BA
- Subjects
- Amino Acid Sequence, Humans, Leucine metabolism, Transcriptional Activation, DNA-Binding Proteins genetics, Transcription Factors metabolism
- Abstract
Acidic activation domains are intrinsically disordered regions of the transcription factors that bind coactivators. The intrinsic disorder and low evolutionary conservation of activation domains have made it difficult to identify the sequence features that control activity. To address this problem, we designed thousands of variants in seven acidic activation domains and measured their activities with a high-throughput assay in human cell culture. We found that strong activation domain activity requires a balance between the number of acidic residues and aromatic and leucine residues. These findings motivated a predictor of acidic activation domains that scans the human proteome for clusters of aromatic and leucine residues embedded in regions of high acidity. This predictor identifies known activation domains and accurately predicts previously unidentified ones. Our results support a flexible acidic exposure model of activation domains in which the acidic residues solubilize hydrophobic motifs so that they can interact with coactivators. A record of this paper's transparent peer review process is included in the supplemental information., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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144. A test of the pioneer factor hypothesis using ectopic liver gene activation.
- Author
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Hansen JL, Loell KJ, and Cohen BA
- Subjects
- Hepatocyte Nuclear Factor 3-alpha metabolism, Hepatocyte Nuclear Factor 4 metabolism, Humans, K562 Cells, Ectopic Gene Expression, Hepatocyte Nuclear Factor 3-alpha genetics, Hepatocyte Nuclear Factor 4 genetics, Liver metabolism
- Abstract
The pioneer factor hypothesis (PFH) states that pioneer factors (PFs) are a subclass of transcription factors (TFs) that bind to and open inaccessible sites and then recruit non-pioneer factors (non-PFs) that activate batteries of silent genes. The PFH predicts that ectopic gene activation requires the sequential activity of qualitatively different TFs. We tested the PFH by expressing the endodermal PF FOXA1 and non-PF HNF4A in K562 lymphoblast cells. While co-expression of FOXA1 and HNF4A activated a burst of endoderm-specific gene expression, we found no evidence for a functional distinction between these two TFs. When expressed independently, both TFs bound and opened inaccessible sites, activated endodermal genes, and 'pioneered' for each other, although FOXA1 required fewer copies of its motif for binding. A subset of targets required both TFs, but the predominant mode of action at these targets did not conform to the sequential activity predicted by the PFH. From these results, we hypothesize an alternative to the PFH where 'pioneer activity' depends not on categorically different TFs but rather on the affinity of interaction between TF and DNA., Competing Interests: JH, KL, BC No competing interests declared, (© 2022, Hansen et al.)
- Published
- 2022
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145. Genomic environments scale the activities of diverse core promoters.
- Author
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Hong CKY and Cohen BA
- Subjects
- Gene Expression Regulation, Promoter Regions, Genetic, Chromatin genetics, Genomics
- Abstract
A classical model of gene regulation is that enhancers provide specificity whereas core promoters provide a modular site for the assembly of the basal transcriptional machinery. However, examples of core promoter specificity have led to an alternate hypothesis in which specificity is achieved by core promoters with different sequence motifs that respond differently to genomic environments containing different enhancers and chromatin landscapes. To distinguish between these models, we measured the activities of hundreds of diverse core promoters in four different genomic locations and, in a complementary experiment, six different core promoters at thousands of locations across the genome. Although genomic locations had large effects on expression, the intrinsic activities of different classes of promoters were preserved across genomic locations, suggesting that core promoters are modular regulatory elements whose activities are independently scaled up or down by different genomic locations. This scaling of promoter activities is nonlinear and depends on the genomic location and the strength of the core promoter. Our results support the classical model of regulation in which diverse core promoter motifs set the intrinsic strengths of core promoters, which are then amplified or dampened by the activities of their genomic environments., (© 2022 Hong and Cohen; Published by Cold Spring Harbor Laboratory Press.)
- Published
- 2022
- Full Text
- View/download PDF
146. Sex- and mutation-specific p53 gain-of-function activity in gliomagenesis.
- Author
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Rockwell NC, Yang W, Warrington NM, Staller MV, Griffith M, Griffith OL, Gurnett CA, Cohen BA, Baldridge D, and Rubin JB
- Subjects
- Animals, Mice, Female, Male, Gain of Function Mutation, Neoplasm Recurrence, Local, Mutation, DNA, Tumor Suppressor Protein p53 genetics, Glioblastoma genetics
- Abstract
In cancer, missense mutations in the DNA-binding domain of TP53 are common. They abrogate canonical p53 activity and frequently confer gain-of-oncogenic function (GOF) through localization of transcriptionally active mutant p53 to non-canonical genes. We found that several recurring p53 mutations exhibit a sex difference in frequency in patients with glioblastoma (GBM). In vitro and in vivo analysis of three mutations, p53
R172H , p53Y202C , and p53Y217C revealed unique interactions between cellular sex and p53 GOF mutations that determined each mutation's ability to transform male versus female primary mouse astrocytes. These phenotypic differences were correlated with sex- and p53 mutation- specific patterns of genomic localization to the transcriptional start sites of upregulated genes belonging to core cancer pathways. The promoter regions of these genes exhibited a sex difference in enrichment for different transcription factor DNA-binding motifs. Together, our data establish a novel mechanism for sex specific mutant p53 GOF activity in GBM with implications for all cancer., Competing Interests: Conflict of Interest: The authors declare no potential conflicts of interest.- Published
- 2021
- Full Text
- View/download PDF
147. Information content differentiates enhancers from silencers in mouse photoreceptors.
- Author
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Friedman RZ, Granas DM, Myers CA, Corbo JC, Cohen BA, and White MA
- Subjects
- Animals, Binding Sites, Female, Male, Mice, Protein Binding, Retina cytology, Retina physiology, Transcription Factors genetics, Photoreceptor Cells physiology, Transcription Factors metabolism
- Abstract
Enhancers and silencers often depend on the same transcription factors (TFs) and are conflated in genomic assays of TF binding or chromatin state. To identify sequence features that distinguish enhancers and silencers, we assayed massively parallel reporter libraries of genomic sequences targeted by the photoreceptor TF cone-rod homeobox (CRX) in mouse retinas. Both enhancers and silencers contain more TF motifs than inactive sequences, but relative to silencers, enhancers contain motifs from a more diverse collection of TFs. We developed a measure of information content that describes the number and diversity of motifs in a sequence and found that, while both enhancers and silencers depend on CRX motifs, enhancers have higher information content. The ability of information content to distinguish enhancers and silencers targeted by the same TF illustrates how motif context determines the activity of cis -regulatory sequences., Competing Interests: RF, DG, CM, JC, BC, MW No competing interests declared, (© 2021, Friedman et al.)
- Published
- 2021
- Full Text
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148. Provocations to Reading: J. Hillis Miller and the Democracy to Come : J. Hillis Miller and the Democracy to Come
- Author
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Cohen, Barbara L., Kujundžić, Dragan, Cohen, Barbara L., and Kujundžić, Dragan
- Published
- 2005
- Full Text
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149. Tinea capitis: advances and a needed paradigm shift.
- Author
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Le TK and Cohen BA
- Subjects
- Antifungal Agents therapeutic use, Arthrodermataceae, Child, Humans, Itraconazole, Microsporum, Naphthalenes, Fluconazole, Tinea Capitis diagnosis, Tinea Capitis drug therapy
- Abstract
Purpose of Review: Tinea capitis, a superficial infection of the scalp, is the most common pediatric dermatophyte fungal infection worldwide and is particularly common in the USA in low-income, low-resource settings. There are still gaps in knowledge and heterogeneities in practice in terms of diagnostic and management strategies. Furthermore, there are no clinical guidelines for management and treatment of tinea capitis in the USA. This review aims to summarize recent advances, recommend optimal management for the practicing pediatrician, and identify areas for future research for tinea capitis., Recent Findings: Trichophyton tonsurans infections are best treated with terbinafine and Microsporum canis infections are best treated with griseofulvin. Trichophyton tonsurans is the predominant cause of tinea capitis in the USA, although the main gold standard of treatment in the USA is griseofulvin. Dermatophyte antifungal resistance is an active area of investigation but seems to not be of current concern for tinea capitis in the USA., Summary: We recommend all clinical providers ascertain the causative organism in fungal infection, either through fungal culture or newer methods which may become more readily available and cost-effective in the future, such as polymerase chain reaction assay. We also recommend terbinafine as first-line treatment of tinea capitis, with adjustment as necessary after species identification., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
150. Heterogeneous cutaneous findings associated with intrauterine HSV infection: A case series and literature review.
- Author
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Pithadia DJ, Kerns ML, Golden WC, Balagula Y, Glick SA, Huang A, Natsis NE, Tom WL, and Cohen BA
- Subjects
- Female, Humans, Infant, Newborn, Multicenter Studies as Topic, Pregnancy, Herpes Simplex complications, Herpes Simplex diagnosis, Infant, Newborn, Diseases, Pregnancy Complications, Infectious, Skin Abnormalities
- Abstract
Background/objective: Herpes simplex virus (HSV) infection acquired in utero may present with non-vesicular dermatologic findings in affected newborns, which may pose a diagnostic dilemma. We aimed to describe and assess the range of non-vesiculobullous skin lesions that neonates with intrauterine HSV infection may manifest at birth., Methods: We collected a multicenter case series and conducted a literature review of neonates with intrauterine HSV infection presenting with non-vesiculobullous cutaneous lesions., Results: Twenty-two cases were reviewed, including six managed clinically by members of our team and 16 identified in the literature. Four (18%) were associated with twin pregnancies, and thirteen (59%) cases occurred in premature infants. Only four (18%) mothers had a documented history of HSV infection. Twelve (55%) cases resulted in poor outcomes, including long-term neurologic sequelae or death. Cutaneous manifestations included erosions, ulcerations, crusted papules or plaques, calcinosis cutis, excoriations, macules (erythematous, hypopigmented, or hyperpigmented), cutaneous atrophy, contractures, and bruising. About one-third of neonates developed new-onset vesicular lesions within a week of birth; in each of these cases, accurate diagnosis and therapy were delayed until appearance of vesicles., Conclusions: The range of dermatologic findings associated with intrauterine HSV is extremely broad, and the various morphologies present at birth likely reflect different stages of the ongoing evolution of an HSV infection that began in utero. Clinicians should have a low threshold for HSV testing in premature neonates born with atypical cutaneous lesions, since early detection and treatment of HSV may reduce morbidity and mortality from systemic complications., (© 2021 The Authors. Pediatric Dermatology published by Wiley Periodicals LLC.)
- Published
- 2021
- Full Text
- View/download PDF
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