Publications by authors named "Dutcher S"

Article Synopsis
  • Primary ciliary dyskinesia (PCD) is a rare genetic disorder linked to chronic respiratory issues, infertility, and problems with body asymmetry, primarily caused by mutations in the CCDC39 and CCDC40 genes.
  • Researchers used advanced techniques to investigate how these genetic variants impact cellular functions beyond just causing cilia to stop moving.
  • They discovered that the absence of CCDC39/CCDC40 creates a significant loss of over 90 ciliary structural proteins, leading to cilia dysfunction and other cellular issues, suggesting that gene therapy could potentially offer a new treatment strategy for PCD.
View Article and Find Full Text PDF
Article Synopsis
  • Primary ciliary dyskinesia (PCD) is a genetic condition that affects tiny hair-like structures called cilia, making them not work properly.
  • Researchers studied cells from patients with PCD, their mothers, and healthy people to understand how these cells are different.
  • They found specific genes and proteins that were linked to problems in cilia movement, which could help develop new treatments for PCD in the future.
View Article and Find Full Text PDF

Purpose: Our objective is to describe how the U.S. Food and Drug Administration (FDA)'s Sentinel System implements best practices to ensure trust in drug safety studies using real-world data from disparate sources.

View Article and Find Full Text PDF

Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue.

View Article and Find Full Text PDF

Introduction: During the COVID-19 pandemic, inpatient electronic health records (EHRs) have been used to conduct public health surveillance and assess treatments and outcomes. Invasive mechanical ventilation (MV) and supplemental oxygen (O) use are markers of severe illness in hospitalized COVID-19 patients. In a large US system (n = 142 hospitals), we assessed documentation of MV and O use during COVID-19 hospitalization in administrative data versus nursing documentation.

View Article and Find Full Text PDF

Motile cilia have essential cellular functions in development, reproduction, and homeostasis. Genetic causes for motile ciliopathies have been identified, but the consequences on cellular functions beyond impaired motility remain unknown. Variants in and cause severe disease not explained by loss of motility.

View Article and Find Full Text PDF

Hydroxyproline-rich glycoproteins (HRGPs) are a ubiquitous class of protein in the extracellular matrices and cell walls of plants and algae, yet little is known of their native structures or interactions. Here, we used electron cryomicroscopy (cryo-EM) to determine the structure of the hydroxyproline-rich mastigoneme, an extracellular filament isolated from the cilia of the alga Chlamydomonas reinhardtii. The structure demonstrates that mastigonemes are formed from two HRGPs (a filament of MST1 wrapped around a single copy of MST3) that both have hyperglycosylated poly(hydroxyproline) helices.

View Article and Find Full Text PDF
Article Synopsis
  • Lasso regression is a common method for estimating propensity scores in large healthcare studies, but undersmoothing can lead to improved confounding control while risking non-overlap in covariate distributions.
  • The study explores how to choose the right level of undersmoothing for Lasso PS models using simulations and a technique called collaborative-controlled targeted learning.
  • Findings indicate that this approach can effectively reduce bias in treatment effect estimates and highlight the importance of cross-fitting to maintain covariate overlap when using undersmoothed models.
View Article and Find Full Text PDF

Motile cilia assembly utilizes over 800 structural and cytoplasmic proteins. Variants in approximately 58 genes cause primary ciliary dyskinesia (PCD) in humans, including the dynein arm (pre)assembly factor (DNAAF) gene DNAAF4. In humans, outer dynein arms (ODAs) and inner dynein arms (IDAs) fail to assemble motile cilia when DNAAF4 function is disrupted.

View Article and Find Full Text PDF

Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue.

View Article and Find Full Text PDF

Purpose: Few studies have examined how the absolute risk of thromboembolism with COVID-19 has evolved over time across different countries. Researchers from the European Medicines Agency, Health Canada, and the United States (US) Food and Drug Administration established a collaboration to evaluate the absolute risk of arterial (ATE) and venous thromboembolism (VTE) in the 90 days after diagnosis of COVID-19 in the ambulatory (eg, outpatient, emergency department, nursing facility) setting from seven countries across North America (Canada, US) and Europe (England, Germany, Italy, Netherlands, and Spain) within periods before and during COVID-19 vaccine availability.

Patients And Methods: We conducted cohort studies of patients initially diagnosed with COVID-19 in the ambulatory setting from the seven specified countries.

View Article and Find Full Text PDF

To identify proteins specific to the proximal ciliary axoneme, we used iTRAQ to compare short (~2 μm) and full-length (~11 μm) axonemes of Chlamydomonas. Known components of the proximal axoneme such as minor dynein heavy chains and LF5 kinase as well as the ciliary tip proteins FAP256 (CEP104) and EB1 were enriched in short axonemes whereas proteins present along the length of the axoneme were of similar abundance in both samples. The iTRAQ analysis revealed that FAP93, a protein of unknown function, and protein phosphatase 2A (PP2A) are enriched in the short axonemes.

View Article and Find Full Text PDF
Article Synopsis
  • Long non-coding RNAs (lncRNAs) play crucial roles in regulating lipid metabolism and have been studied in relation to genetic variants and complex traits.
  • This research utilized high-coverage whole-genome sequencing of over 66,000 diverse participants to assess how rare variants in lncRNA genes affect blood lipid levels, using a statistical framework to analyze the associations.
  • The study found 83 lncRNA variants significantly linked to lipid levels, with many being independent of common genetic variations, and replicated a majority of these findings with data from another large cohort.
View Article and Find Full Text PDF

We described care received by hospitalized children with COVID-19 or multi-system inflammatory syndrome (MIS-C) prior to the 2021 COVID-19 Omicron variant surge in the US. We identified hospitalized children <18 years of age with a COVID-19 or MIS-C diagnosis (COVID-19 not required), separately, from February 2020-September 2021 (n = 126 hospitals). We described high-risk conditions, inpatient treatments, and complications among these groups.

View Article and Find Full Text PDF
Article Synopsis
  • Long non-coding RNAs (lncRNAs) play key roles in regulating biological functions, and new genomic studies allow researchers to explore their connection to complex traits, like blood lipid levels.
  • This research involved high-coverage whole genome sequencing from over 66,000 participants, focusing on the influence of rare variants in 165,375 lncRNA genes on lipid variability.
  • The study found 83 rare lncRNA variant sets linked to blood lipid levels, with many of these associations being independent of common variants, suggesting potential new avenues for therapeutic interventions.
View Article and Find Full Text PDF

Congress mandated the creation of a postmarket Active Risk Identification and Analysis (ARIA) system containing data on 100 million individuals for monitoring risks associated with drug and biologic products using data from disparate sources to complement the US Food and Drug Administration's (FDA's) existing postmarket capabilities. We report on the first 6 years of ARIA utilization in the Sentinel System (2016-2021). The FDA has used the ARIA system to evaluate 133 safety concerns; 54 of these evaluations have closed with regulatory determinations, whereas the rest remain in progress.

View Article and Find Full Text PDF

Purpose: Immediate-release forms of generic mixed amphetamine salts (MAS) have been the subject of passive surveillance reports signaling lack of effectiveness. We examined switching patterns that might suggest whether long-term users of specific MAS are more likely to switch away or switch back after use of the MAS of interest in the FDA's Sentinel Distributed Database.

Methods: We required at least 60-day continuous supply of selected MAS grouped by Abbreviated New Drug Application (ANDA) to describe patterns of switching away from and to generics approved under the ANDAs of interest among individuals ages 15-64 years with attention deficit hyperactivity disorder or narcolepsy during 2013-2019.

View Article and Find Full Text PDF

Sperm motility is crucial to reproductive success in sexually reproducing organisms. Impaired sperm movement causes male infertility, which is increasing globally. Sperm are powered by a microtubule-based molecular machine-the axoneme-but it is unclear how axonemal microtubules are ornamented to support motility in diverse fertilization environments.

View Article and Find Full Text PDF

We report a label-free acoustic microfluidic method to confine single, cilia-driven swimming cells in space without limiting their rotational degrees of freedom. Our platform integrates a surface acoustic wave (SAW) actuator and bulk acoustic wave (BAW) trapping array to enable multiplexed analysis with high spatial resolution and trapping forces that are strong enough to hold individual microswimmers. The hybrid BAW/SAW acoustic tweezers employ high-efficiency mode conversion to achieve submicron image resolution while compensating for parasitic system losses to immersion oil in contact with the microfluidic chip.

View Article and Find Full Text PDF

Objective: To measure the 90 day risk of arterial thromboembolism and venous thromboembolism among patients diagnosed with covid-19 in the ambulatory (ie, outpatient, emergency department, or institutional) setting during periods before and during covid-19 vaccine availability and compare results to patients with ambulatory diagnosed influenza.

Design: Retrospective cohort study.

Setting: Four integrated health systems and two national health insurers in the US Food and Drug Administration's Sentinel System.

View Article and Find Full Text PDF
Article Synopsis
  • DNAAF5 is a factor linked to primary ciliary dyskinesia (PCD), a genetic condition affecting motile cilia, and its heterozygosity's effects on cilia function were investigated using CRISPR-Cas9 in mice.
  • Mice with different Dnaaf5 gene variants exhibited significant differences in disease severity; those with one missense mutation had better survival and partially functioning cilia compared to those with a null allele or a combination of both.
  • Proteomic and transcriptional analyses indicated variability in protein expression and functionality across different tissues, emphasizing the complexity of genetic influences on cilia assembly and related health outcomes in PCD.
View Article and Find Full Text PDF
Article Synopsis
  • Researchers compiled a comprehensive catalog of 355,667 structural variants (SVs) from DNA data, with over half being novel, to better understand the relationship between SVs and diseases.
  • The study involved rigorous methods to ensure high-quality variant identification, showing over 90% accuracy compared to previous genetic assemblies.
  • This catalog reveals significant connections between SVs and various health traits, identifying 690 specific regions that may influence medically relevant genes, providing a crucial resource for disease research.
View Article and Find Full Text PDF

Ever larger Structural Variant (SV) catalogs highlighting the diversity within and between populations help researchers better understand the links between SVs and disease. The identification of SVs from DNA sequence data is non-trivial and requires a balance between comprehensiveness and precision. Here we present a catalog of 355,667 SVs (59.

View Article and Find Full Text PDF

Unlabelled: DNAAF5 is a dynein motor assembly factor associated with the autosomal heterogenic recessive condition of motile cilia, primary ciliary dyskinesia (PCD). The effects of allele heterozygosity on motile cilia function are unknown. We used CRISPR-Cas9 genome editing in mice to recreate a human missense variant identified in patients with mild PCD and a second, frameshift null deletion in .

View Article and Find Full Text PDF