Publications by authors named "John D Gillece"

The animal gut microbiome can have a strong influence on the health, fitness, and behavior of its hosts. The composition of the gut microbial community can be influenced by factors such as diet, environment, and evolutionary history (phylosymbiosis). However, the relative influence of these factors is unknown in most bird species.

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Background And Aims: Although the benefits of vertical sleeve gastrectomy (VSG) surgery are well known, the molecular mechanisms by which VSG alleviates obesity and its complications remain unclear. We aim to determine the role of CYP8B1 (cytochrome P450, family 8, subfamily B, polypeptide 1) in mediating the metabolic benefits of VSG.

Approach And Results: We found that expression of CYP8B1, a key enzyme in controlling the 12α-hydroxylated (12α-OH) bile acid (BA) to non-12α-OH BA ratio, was strongly downregulated after VSG.

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Numerous genotyping techniques based on different principles and with different costs and levels of resolution are currently available for understanding the transmission dynamics of brucellosis worldwide. We aimed to compare the population structure of the genomes of 53 Brazilian Brucella abortus isolates using eight different genotyping methods: multiple-locus variable-number tandem-repeat analysis (MLVA8, MLVA11, MLVA16), multilocus sequence typing (MLST9, MLST21), core genome MLST (cgMLST) and two techniques based on single nucleotide polymorphism (SNP) detection (parSNP and NASP) from whole genomes. The strains were isolated from six different Brazilian states between 1977 and 2008 and had previously been analyzed using MLVA8, MLVA11, and MLVA16.

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The National Aeronautics and Space Administration (NASA) has been monitoring the microbial burden of spacecraft since the 1970's Viking missions. Originally culture-based and then focused 16S sequencing techniques were used, but we have now applied whole metagenomic sequencing to a variety of cleanroom samples at the Jet Propulsion Lab (JPL), including the Spacecraft Assembly Facility (SAF) with the goals of taxonomic identification and for functional assignment. Our samples included facility pre-filters, cleanroom vacuum debris, and surface wipes.

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Unlabelled: Neratinib has great efficacy in treating HER2+ breast cancer but is associated with significant gastrointestinal toxicity. The objective of this pilot study was to understand the association of gut microbiome and neratinib-induced diarrhea. Twenty-five patients (age ≥ 60) were enrolled in a phase II trial evaluating safety and tolerability of neratinib in older adults with HER2+ breast cancer (NCT02673398).

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Lessons Learned: The combination of enobosarm and pembrolizumab was well tolerated and showed a modest clinical benefit rate of 25% at 16 weeks. Future trials investigating androgen receptor-targeted therapy in combination with immune checkpoint inhibitors are warranted.

Background: Luminal androgen receptor is a distinct molecular subtype of triple-negative breast cancer (TNBC) defined by overexpression of androgen receptor (AR).

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Viruses and plasmids (invasive mobile genetic elements (iMGEs)) have important roles in shaping microbial communities, but their dynamic interactions with CRISPR-based immunity remain unresolved. We analysed generation-resolved iMGE-host dynamics spanning one and a half years in a microbial consortium from a biological wastewater treatment plant using integrated meta-omics. We identified 31 bacterial metagenome-assembled genomes encoding complete CRISPR-Cas systems and their corresponding iMGEs.

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Studies suggest a link between the gut microbiome and metastatic renal cell carcinoma (mRCC) outcomes, including evidence that mRCC patients possess a lower abundance of Bifidobacterium spp. compared to healthy adults. We sought to assess if a Bifidobacterium-containing yogurt product could modulate the gut microbiome and clinical outcome from vascular endothelial growth factor-tyrosine kinase inhibitors (VEGF-TKIs).

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The development of reliable, mixed-culture biotechnological processes hinges on understanding how microbial ecosystems respond to disturbances. Here we reveal extensive phenotypic plasticity and niche complementarity in oleaginous microbial populations from a biological wastewater treatment plant. We perform meta-omics analyses (metagenomics, metatranscriptomics, metaproteomics and metabolomics) on in situ samples over 14 months at weekly intervals.

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Preclinical models and early clinical data suggest an interplay between the gut microbiome and response to immunotherapy in solid tumors including metastatic renal cell carcinoma (mRCC). We sought to characterize the stool microbiome of mRCC patients receiving a checkpoint inhibitor (CPI) and to assess treatment-related changes in microbiome composition over the course of CPI therapy. Stool was collected from 31 patients before initiation of nivolumab (77%) or nivolumab plus ipilimumab (23%) therapy, of whom 58% experienced clinical benefit.

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The Gram-negative beta-proteobacterium sp. LCSB751 (LMG 29444) was newly isolated from foaming activated sludge of a municipal wastewater treatment plant. Here, we describe its draft genome sequence and annotation together with a general physiological and genomic analysis, as the first sequenced representative of the genus.

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The bacterium Burkholderia ubonensis is commonly co-isolated from environmental specimens harbouring the melioidosis pathogen, Burkholderia pseudomallei. B. ubonensis has been reported in northern Australia and Thailand but not North America, suggesting similar geographic distribution to B.

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Article Synopsis
  • This study explores the differences in microbiota from the middle meatus (MM) and inferior meatus (IM) in healthy individuals, those with allergic rhinitis (AR), and chronic rhinosinusitis (CRS).
  • Researchers collected endoscope-guided swab samples from 65 subjects and analyzed bacterial diversity via sequencing.
  • Results indicated that CRS patients showed lower diversity in MM samples compared to healthy subjects and AR, with specific bacteria like Streptococcus and Fusobacterium being more prevalent in CRS, highlighting important differences in sinonasal microbiomes.
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Whole-genome sequencing (WGS) of bacterial isolates has become standard practice in many laboratories. Applications for WGS analysis include phylogeography and molecular epidemiology, using single nucleotide polymorphisms (SNPs) as the unit of evolution. NASP was developed as a reproducible method that scales well with the hundreds to thousands of WGS data typically used in comparative genomics applications.

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Nosocomial acquisition of Clostridium difficile is well documented, yet recent studies have highlighted the importance of community acquired infections and identified community associated reservoirs for this pathogen. Multiple studies have implicated companion pets and farm animals as possible sources of community acquired C. difficile infections in humans.

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Unlabelled: Anthrax is a zoonotic disease that occurs naturally in wild and domestic animals but has been used by both state-sponsored programs and terrorists as a biological weapon. A Soviet industrial production facility in Sverdlovsk, USSR, proved deficient in 1979 when a plume of spores was accidentally released and resulted in one of the largest known human anthrax outbreaks. In order to understand this outbreak and others, we generated a Bacillus anthracis population genetic database based upon whole-genome analysis to identify all single-nucleotide polymorphisms (SNPs) across a reference genome.

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Article Synopsis
  • Drug-resistant tuberculosis (DR-TB) is a significant global health issue, making TB the leading infectious cause of death, and precise drug resistance profiling can lead to better, individualized treatments.
  • A pilot study showcased a new targeted next-generation sequencing (NGS) method called Next Gen-RDST, which allows rapid analysis of drug resistance directly from patient sputum samples, significantly speeding up results compared to traditional methods.
  • The study found a 94.3% success rate in generating complete drug resistance profiles from Moldovan samples, with a high agreement (97%) with existing testing methods, demonstrating the assay's potential for clinical and public health applications.
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Staphylococcus aureus is an important clinical pathogen worldwide and understanding this organism's phylogeny and, in particular, the role of recombination, is important both to understand the overall spread of virulent lineages and to characterize outbreaks. To further elucidate the phylogeny of S. aureus, 35 diverse strains were sequenced using whole genome sequencing.

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Background: Mixed microbial communities underpin important biotechnological processes such as biological wastewater treatment (BWWT). A detailed knowledge of community structure and function relationships is essential for ultimately driving these systems towards desired outcomes, e.g.

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Microbial communities are complex and dynamic systems that are primarily structured according to their members' ecological niches. To investigate how niche breadth (generalist versus specialist lifestyle strategies) relates to ecological success, we develop and apply an integrative workflow for the multi-omic analysis of oleaginous mixed microbial communities from a biological wastewater treatment plant. Time- and space-resolved coupled metabolomic and taxonomic analyses demonstrate that the community-wide lipid accumulation phenotype is associated with the dominance of the generalist bacterium Candidatus Microthrix spp.

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The emergence of distinct populations of Cryptococcus gattii in the temperate North American Pacific Northwest (PNW) was surprising, as this species was previously thought to be confined to tropical and semitropical regions. Beyond a new habitat niche, the dominant emergent population displayed increased virulence and caused primary pulmonary disease, as opposed to the predominantly neurologic disease seen previously elsewhere. Whole-genome sequencing was performed on 118 C.

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Exserohilum rostratum was the cause of most cases of fungal meningitis and other infections associated with the injection of contaminated methylprednisolone acetate produced by the New England Compounding Center (NECC). Until this outbreak, very few human cases of Exserohilum infection had been reported, and very little was known about this dematiaceous fungus, which usually infects plants. Here, we report using whole-genome sequencing (WGS) for the detection of single nucleotide polymorphisms (SNPs) and phylogenetic analysis to investigate the molecular origin of the outbreak using 22 isolates of E.

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Background: Cryptococcus gattii has been the cause of an ongoing outbreak starting in 1999 on Vancouver Island, British Columbia and spreading to mainland Canada and the US Pacific Northwest. In the course of the outbreak, C. gattii has been identified outside of its previously documented climate, habitat, and host disease.

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We used whole-genome analysis and subsequent characterization of geographically diverse strains using new genetic signatures to identify distinct subgroups within Francisella tularensis subsp. tularensis group A.I: A.

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Acinetobacter baumannii is an emergent and global nosocomial pathogen. In addition to A. baumannii, other Acinetobacter species, especially those in the Acinetobacter calcoaceticus-baumannii (Acb) complex, have also been associated with serious human infection.

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