Publications by authors named "Steven Guard"

The nonpsychoactive cannabinoid, cannabidiol (CBD), is Food and Dug Administration approved for treatment of two drug-resistant epileptic disorders and is seeing increased use among the general public, yet the mechanisms that underlie its therapeutic effects and side-effect profiles remain unclear. Here, we report a systems-level analysis of CBD action in human cell lines using temporal multiomic profiling. FRET-based biosensor screening revealed that CBD elicits a sharp rise in cytosolic calcium, and activation of AMP-activated protein kinase in human keratinocyte and neuroblastoma cell lines.

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Immunoaffinity purification mass spectrometry (IP-MS) has emerged as a robust quantitative method of identifying protein-protein interactions. This publication presents a complete interaction proteomics workflow designed for identifying low abundance protein-protein interactions from the nucleus that could also be applied to other subcellular compartments. This workflow includes subcellular fractionation, immunoprecipitation, sample preparation, offline cleanup, single-shot label-free mass spectrometry, and downstream computational analysis and data visualization.

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The chromosome 21 encoded protein kinase DYRK1A is essential for normal human development. Mutations in DYRK1A underlie a spectrum of human developmental disorders, and increased dosage in trisomy 21 is implicated in Down syndrome related pathologies. DYRK1A regulates a diverse array of cellular processes through physical interactions with substrates and binding partners in various subcellular compartments.

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Neurofibromatosis type 2 is an inherited, neoplastic disease associated with schwannomas, meningiomas, and ependymomas and that is caused by inactivation of the tumor suppressor gene The gene product, Merlin, has no intrinsic catalytic activity; its tumor suppressor function is mediated through the proteins with which it interacts. We used proximity biotinylation followed by mass spectrometry and direct binding assays to identify proteins that associated with wild-type and various mutant forms of Merlin in immortalized Schwann cells. We defined a set of 52 proteins in close proximity to wild-type Merlin.

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Article Synopsis
  • Coinheritance of mutations in the CDKN2A gene and the loss-of-function variant in the MC1R gene increases the risk of developing melanoma.
  • Researchers conducted experiments on human melanocyte cultures from individuals with CDKN2A mutations, revealing normal growth and response to UV radiation in most cultures.
  • The study suggests that for melanocytes with both CDKN2A mutations and MC1RLOF variants to become cancerous, they need to acquire additional mutations, influenced by their genetic environment or surrounding cell types.
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Aims: To present final efficacy/safety results from a prospective, long-term extension trial of onabotulinumtoxinA for urinary incontinence (UI) due to neurogenic detrusor overactivity (NDO); patients received treatment for up to 4 years.

Methods: Patients who completed a 52-week, phase III trial of onabotulinumtoxinA for NDO were eligible to enter a 3-year, multicenter, open-label extension study of intradetrusor onabotulinumtoxinA (200U or 300U). Patients were treated "as needed" based on their request and fulfillment of prespecified qualification criteria (≥12 weeks since previous treatment and a UI episode threshold).

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