Publications by authors named "Southard K"

Single-cell CRISPR screens link genetic perturbations to transcriptional states, but high-throughput methods connecting these induced changes to their regulatory foundations are limited. Here, we introduce Multiome Perturb-seq, extending single-cell CRISPR screens to simultaneously measure perturbation-induced changes in gene expression and chromatin accessibility. We apply Multiome Perturb-seq in a CRISPRi screen of 13 chromatin remodelers in human RPE-1 cells, achieving efficient assignment of sgRNA identities to single nuclei via an improved method for capturing barcode transcripts from nuclear RNA.

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Cell atlas projects have nominated recurrent transcriptional states as drivers of biological processes and disease, but their origins, regulation, and properties remain unclear. To enable complementary functional studies, we developed a scalable approach for recapitulating cell states using CRISPR activation (CRISPRa) Perturb-seq. Aided by a novel multiplexing method, we activated 1,836 transcription factors in two cell types.

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Single-cell CRISPR screens link genetic perturbations to transcriptional states, but high-throughput methods connecting these induced changes to their regulatory foundations are limited. Here we introduce Multiome Perturb-seq, extending single-cell CRISPR screens to simultaneously measure perturbation-induced changes in gene expression and chromatin accessibility. We apply Multiome Perturb-seq in a CRISPRi screen of 13 chromatin remodelers in human RPE-1 cells, achieving efficient assignment of sgRNA identities to single nuclei via an improved method for capturing barcode transcripts from nuclear RNA.

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Objectives: Cerebral amyloid angiopathy (CAA) related inflammation (CAA-RI) is an autoimmune inflammatory condition occurring in patients with CAA. We aimed to determine the prevalence of radiological CAA-RI amongst patients with CAA and to describe their presenting clinical features.

Methods: We performed a retrospective review of electronic medical records across multiple centers within a single healthcare network.

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Introduction: Medically unnecessary, potentially preventable transfers of nursing home (NH) residents to acute care poses multiple risks for residents. Family and resident insistence on these preventable transfers has not been thoroughly addressed in transfer reduction programs.

Methods: The Diffusion of Innovation model guided dissemination of an evidence-based patient decision guide that addressed resident and family insistence on hospital transfer.

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Adherens junctions (AJs) create spatially, chemically and mechanically discrete microdomains at cellular interfaces. Here, using a mechanogenetic platform that generates artificial AJs with controlled protein localization, clustering and mechanical loading, we find that AJs also organize proteolytic hotspots for γ-secretase with a spatially regulated substrate selectivity that is critical in the processing of Notch and other transmembrane proteins. Membrane microdomains outside of AJs exclusively organize Notch ligand-receptor engagement (LRE microdomains) to initiate receptor activation.

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National prevalence data indicate that college students are at a high risk for sexual assault, but most institutions of higher education do not provide postassault medical forensic examinations as part of student-facing healthcare services. College sexual assault patients might have access to sexual assault nurse examiners (SANEs) in local hospitals, if they are available where they are attending school, but unfortunately, many student victims do not have options for postassault health services. Creating campus-based SANE programs could address this gap in services and increase access to healthcare.

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Limited access to undergraduate research experiences for science, technology, engineering, and mathematics students has led to creation of classroom-based opportunities for students to participate in authentic science. Revising laboratory courses to engage students in the practices of science has been shown to have many benefits for students. However, the instructor's role in successful implementation of authentic-inquiry curricula requires further investigation.

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Objectives: The long-term skeletal effects of Class II treatment in growing individuals using high-pull facebow headgear and fixed edgewise appliances have not been reported. The purpose of this study was to evaluate the long-term skeletal effects of treatment using high-pull headgear followed by fixed orthodontic appliances compared to an untreated control group.

Materials And Methods: Changes in anteroposterior and vertical cephalometric measurements of 42 Class II subjects (n = 21, mean age = 10.

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The ability to sense and manipulate the state of biological systems has been extensively advanced during the past decade with the help of recent developments in physical tools. Unlike standard genetic and pharmacological perturbation techniques-knockdown, overexpression, small molecule inhibition-that provide a basic on/off switching capability, these physical tools provide the capacity to control the spatial, temporal, and mechanical properties of the biological targets. Among the various physical cues, magnetism offers distinct advantages over light or electricity.

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Spatiotemporal interrogation of signal transduction at the single-cell level is necessary to answer a host of important biological questions. This protocol describes a nanotechnology-based single-cell and single-molecule perturbation tool, termed mechanogenetics, that enables precise spatial and mechanical control over genetically encoded cell-surface receptors in live cells. The key components of this tool are a magnetoplasmonic nanoparticle (MPN) actuator that delivers defined spatial and mechanical cues to receptors through target-specific one-to-one engagement and a micromagnetic tweezers (μMT) that remotely controls the magnitude of force exerted on a single MPN.

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Tools capable of imaging and perturbing mechanical signaling pathways with fine spatiotemporal resolution have been elusive, despite their importance in diverse cellular processes. The challenge in developing a mechanogenetic toolkit (i.e.

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Digital PCR (dPCR) is an emerging technology for genetic analysis and clinical diagnostics. To facilitate the widespread application of dPCR, here we developed a new micropatterned superporous absorbent array chip (μSAAC) which consists of an array of microwells packed with highly porous agarose microbeads. The packed beads construct a hierarchically porous microgel which confers superior water adsorption capacity to enable spontaneous filling of PDMS microwells for fluid compartmentalization without the need of sophisticated microfluidic equipment and operation expertise.

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Research has suggested that teaching and learning in molecular and cellular biology (MCB) is difficult. We used a new lens to understand undergraduate reasoning about molecular mechanisms: the knowledge-integration approach to conceptual change. Knowledge integration is the dynamic process by which learners acquire new ideas, develop connections between ideas, and reorganize and restructure prior knowledge.

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The inpatient environment is a critical space for nurses and patients in psychiatric settings. In this article, we describe nurses' and patients' perceptions of the inpatient environment both before the removal of a Plexiglas enclosure around a nurses' station and after its removal. Nurses had mixed feelings about the enclosure, reporting that it provided for confidentiality and a concentrated work space but also acknowledged the challenge of the barrier for communication with their patients.

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The multivalent nature of commercial quantum dots (QDs) and the difficulties associated with producing monovalent dots have limited their applications in biology, where clustering and the spatial organization of biomolecules is often the object of study. We describe here a protocol to produce monovalent quantum dots (mQDs) that can be accomplished in most biological research laboratories via a simple mixing of CdSe/ZnS core/shell QDs with phosphorothioate DNA (ptDNA) of defined length. After a single ptDNA strand has wrapped the QD, additional strands are excluded from the surface.

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Previous research has shown that undergraduate science students learn from peer discussions of in-class clicker questions. However, the features that characterize such discussions are largely unknown, as are the instructional factors that may lead students into productive discussions. To explore these questions, we recorded and transcribed 83 discussions among groups of students discussing 34 different clicker questions in an upper-level developmental biology class.

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Specific efforts by hospital accreditation organizations encourage renovation of nursing stations, so nurses can better see, attend, and care for their patients. The purpose of this study was to examine the effect of nursing station design on the therapeutic milieu in an adult acute care psychiatric unit. A repeated cross-sectional, pretest-posttest design was used.

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Introduction: Headgears have been used to treat Class II malocclusions for over a century. The purpose of this retrospective study was to investigate the profile esthetic changes resulting from headgear use in growing Class II patients with protrusive, normal, and retrusive maxillae.

Methods: Profile silhouettes were created from pretreatment and posttreatment lateral cephalometric tracings of growing Class II patients treated with headgear followed by conventional fixed appliances.

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This case report describes the treatment of a 25-year-old woman with a Class II malocclusion, secondary to mandibular skeletal deficiency, and mild overclosure. Inferior surgical repositioning of the maxilla is often the treatment of choice for patients with maxillary vertical deficiency; however, this patient had borderline vertical deficiency that was treated with a mandibular "tripod" advancement (leveling of the mandibular arch after surgery) coupled with a setback and down-grafting genioplasty. The surgical-orthodontic treatment plan, combined with cosmetic dentistry, resulted in dramatically improved facial esthetics and occlusal relationships.

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Introduction: The cervical vertebrae maturation (CVM) method has been advocated as a predictor of peak mandibular growth. This method relies on the clinician's ability to determine the stage of maturation of the vertebrae. Careful examination of reports of this technique shows methodologic flaws that can lead to inflated levels of reproducibility.

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Introduction: Many case reports have documented the successful use of titanium miniscrews for orthodontic anchorage. However, the literature lacks a well-controlled study examining the effect of miniscrew diameter on anchorage force resistance. The purpose of this in-vitro study was to compare the force resistance of larger-diameter monocortical miniscrews to smaller-diameter monocortical miniscrews; and to compare the force resistance of larger-diameter monocortical miniscrews to smaller-diameter bicortical miniscrews.

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Introduction: Case reports have documented the use of titanium miniscrews in providing skeletal anchorage for orthodontic tooth movement. Success rates as low as 50% have been reported for screw retention in either the facial or the lingual cortical plates (monocortical placement). The purpose of this in-vitro study was to test the hypothesis that bicortical miniscrew placement (across the entire width of the alveolus) gives the orthodontist superior force resistance and stability (anchorage) compared with monocortical placement.

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Introduction: Herbst and headgear appliances are considered effective for correcting Class II malocclusions in growing patients, although their skeletal and dental effects differ. In the literature, there is no comparison between profile esthetic outcomes with the Herbst and headgear. The purpose of this study was to provide that comparison.

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