Publications by authors named "Randall Olsen"

Objectives: An increase in Streptococcus dysgalactiae subsp. equisimilis (SDSE) infections has been documented worldwide. This study aims to analyse invasive disease caused by SDSE (iSDSE) in adults over an 11-year period in Spain.

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Background: CALR mutation analysis is routinely used to diagnose BCR/ABL1-negative myeloproliferative neoplasms. The 2 most common CALR mutations are a 52-base pair (bp) deletion and a 5-bp insertion, which account for approximately 85% of cases.

Methods: To evaluate our new microfluidic chip assay, we tested CALR mutant and wild-type specimens that were previously analyzed using conventional methods at a reference laboratory.

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Over the last four years, each successive wave of the COVID-19 pandemic has been caused by variants with mutations that improve the transmissibility of the virus. Despite this, we still lack tools for predicting clinically important features of the virus. In this study, we show that it is possible to predict the PCR cycle threshold (Ct) values from clinical detection assays using sequence data.

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Unlabelled: subspecies (SDSE) is a Gram-positive bacterial pathogen that infects humans and is closely related to group A streptococcus (GAS). Compared with GAS, far less is known about SDSE pathobiology. Increased rates of invasive SDSE infections have recently been reported in many countries.

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Immune checkpoint inhibitors (ICIs) drastically improve therapeutic outcomes for lung cancer, but accurately predicting individual patient responses to ICIs remains a challenge. We performed the genome-wide profiling of 5-hydroxymethylcytosine (5hmC) in 85 plasma cell-free DNA (cfDNA) samples from lung cancer patients and developed a 5hmC signature that was significantly associated with progression-free survival (PFS). We built a 5hmC predictive model to quantify the 5hmC level and validated the model in the validation, test, and control sets.

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Group A isolates of the recently described M1 clade have emerged to cause human infections in several European countries and elsewhere. Full-genome sequence analysis of M1 isolates discovered a close genomic relationship between some isolates from Scotland and the majority of isolates from Iceland causing serious infections in 2022 and 2023. Phylogenetic analysis strongly suggests that an isolate from or related to Scotland was the precursor to an M1 variant responsible for almost all recent M1 infections in Iceland.

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Accurate prognostic markers are essential for guiding effective lung cancer treatment strategies. The level of 5-hydroxymethylcytosine (5hmC) in tissue is independently associated with overall survival (OS) in lung cancer patients. We explored the prognostic value of cell-free DNA (cfDNA) 5hmC through genome-wide analysis of 5hmC in plasma samples from 97 lung cancer patients.

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Probiotic supplements are suggested to promote human health by preventing pathogen colonization. However, the mechanistic bases for their efficacy in vivo are largely uncharacterized. Here using metabolomics and bacterial genetics, we show that the human oral probiotic Streptococcus salivarius K12 (SAL) produces salivabactin, an antibiotic that effectively inhibits pathogenic Streptococcus pyogenes (GAS) in vitro and in mice.

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Streptococcus dysgalactiae subsp. is a bacterial pathogen that is increasingly recognized as a cause of severe human infections. Much less is known about the genomics and infection pathogenesis of S.

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There is mounting evidence of SARS-CoV-2 spillover from humans into many domestic, companion, and wild animal species. Research indicates that humans have infected white-tailed deer, and that deer-to-deer transmission has occurred, indicating that deer could be a wildlife reservoir and a source of novel SARS-CoV-2 variants. We examined the hypothesis that the Omicron variant is actively and asymptomatically infecting the free-ranging deer of New York City.

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Group A streptococcus (GAS) is a Gram-positive human bacterial pathogen responsible for more than 700 million infections annually worldwide. Beta-lactam antibiotics are the primary agents used to treat GAS infections. Naturally occurring GAS clinical isolates with decreased susceptibility to beta-lactam antibiotics attributed to mutations in PBP2X have recently been documented.

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The COVID-19 pandemic has resulted in extensive surveillance of the genomic diversity of SARS-CoV-2. Sequencing data generated as part of these efforts can also capture the diversity of the SARS-CoV-2 virus populations replicating within infected individuals. To assess this within-host diversity of SARS-CoV-2 we quantified low frequency (minor) variants from deep sequence data of thousands of clinical samples collected by a large urban hospital system over the course of a year.

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The worldwide spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the repeated emergence of variants of concern. For the Omicron variant, sub-lineages BA.1 and BA.

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All tested strains of Streptococcus pyogenes (group A streptococcus, GAS) remain susceptible to penicillin. However, GAS strains with amino acid substitutions in penicillin-binding proteins that confer decreased susceptibility to beta-lactam antibiotics have been identified recently. This discovery raises concerns about emergence of beta-lactam antibiotic resistance in GAS.

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Article Synopsis
  • * Genomic data was used to trace the transmission history of SARS-CoV-2 between humans and deer, revealing no direct evidence of deer transmitting the virus back to humans, but indicating a low detection rate of cases at only 4.2%.
  • * The significant spread of the virus within deer populations and unsampled cases suggests a need for ongoing monitoring and surveillance where humans and animals interact to prevent potential spillback to humans.
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Objective: To determine the efficacy, safety, and durability of the use of AHCC supplementation for 6 months to support the host immune system to clear high-risk human papillomavirus (HPV) infections. The AHCC supplement is a proprietary, standardized extract of cultured lentinula edodes mycelia (AHCC, Amino Up, Ltd., Sapporo, Japan) that has been shown to have unique immune modulatory benefits.

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In the two decades since Accreditation Council for Graduate Medical Education-accredited Molecular Genetic Pathology fellowships began, the field of clinical molecular pathology has evolved considerably. The American Board of Pathology gathered data from board-certified molecular genetic pathologists assessing the alignment of skills and knowledge gained during fellowship with current needs on the job. The Association of Molecular Pathology conducted a parallel survey of program directors, and included questions on how various topics were taught during fellowship, as well as ranking their importance.

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Background: mutations are the most common oncogenic driver mutations of non-small cell lung cancer (NSCLC) in the Western world. Mutations of the gene are most prevalent in the patient population of current and former cigarette smokers. With the recent pivotal approval of a targeted inhibitor therapy for patients with p.

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Unlabelled: White-tailed deer ( ) are highly susceptible to infection by SARS-CoV-2, with multiple reports of widespread spillover of virus from humans to free-living deer. While the recently emerged SARS-CoV-2 B.1.

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Genetic variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to dramatically alter the landscape of the coronavirus disease 2019 (COVID-19) pandemic. The recently described variant of concern designated Omicron (B.1.

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Article Synopsis
  • Many animal species, including white-tailed deer, can contract SARS-CoV-2, and there’s evidence that deer can transmit the virus to one another.
  • A study conducted in Iowa from April 2020 to January 2021 found that 33.2% of sampled deer tested positive for SARS-CoV-2 RNA, with a significant spike during the peak of human cases and the deer hunting season.
  • The research identified 12 lineages of the virus in deer, suggesting multiple instances of human-to-deer transmission, indicating a need for a comprehensive "One Health" approach to better understand how SARS-CoV-2 spreads among animals and humans.
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Introduction: Manual gating of flow cytometry (FCM) data for marrow cell analysis is a standard approach in current practice, although it is time- and labor-consuming. Recent advances in cytometry technology have led to significant efforts in developing partially or fully automated analysis methods. Although multiple supervised and unsupervised FCM data analysis algorithms have been developed, they have not been widely adopted by the clinical and research laboratories.

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Identification of genetic polymorphisms causing increased antibiotic resistance in bacterial pathogens traditionally has proceeded from observed phenotype to defined mutant genotype. The availability of large collections of microbial genome sequences that lack antibiotic susceptibility metadata provides an important resource and opportunity to obtain new information about increased antimicrobial resistance by a reverse genotype-to-phenotype bioinformatic and experimental workflow. We analyzed 26,465 genome sequences of Streptococcus pyogenes, a human pathogen causing 700 million infections annually.

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The ARTIC Network provides a common resource of PCR primer sequences and recommendations for amplifying SARS-CoV-2 genomes. The initial tiling strategy was developed with the reference genome Wuhan-01, and subsequent iterations have addressed areas of low amplification and sequence drop out. Recently, a new version (V4) was released, based on new variant genome sequences, in response to the realization that some V3 primers were located in regions with key mutations.

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