Publications by authors named "Amy M Chan"

The Pacific oyster is the most widely cultured shellfish worldwide, but production has been affected by mortality events, including in hatcheries that supply the seed for growers. Several pathogens cause disease in oysters, but in many cases, mortality events cannot be attributed to a single agent and appear to be multifactorial, involving environmental variables and microbial interactions. As an organism's microbiome can provide resilience against pathogens and environmental stressors, we investigated the microbiomes in cohorts of freshly settled oyster spat, some of which experienced notable mortality.

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Maintaining genetic diversity in cultured shellfish can be challenging due to high variance in individual reproductive success, founder effects, and rapid genetic drift, but is important to retain adaptive potential and avoid inbreeding depression. To support broodstock management and selective breeding in cultured Pacific oysters (Crassostrea (Magallana) gigas), we developed an amplicon panel targeting 592 genomic regions and SNP variants with an average of 50 amplicons per chromosome. Target SNPs were selected based on elevated observed heterozygosity or differentiation in Pacific oyster populations in British Columbia, Canada.

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Vibrio natriegens strain PWH3a, isolated from the Texas Gulf Coast, is used as a model organism in marine microbiology. Here, we report the complete genome sequence of strain PWH3a, which has two circular chromosomes, 4,650 coding sequences, 34 rRNA, 4 noncoding RNA (ncRNA), 131 tRNA genes, and one Mu-like prophage sequence.

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Microbes are by far the dominant biomass in the world's oceans and drive biogeochemical cycles that are critical to life on Earth. The composition of marine microbial communities is highly dynamic, spatially and temporally, with consequent effects on their functional roles. In part, these changes in composition result from viral lysis, which is taxon-specific and estimated to account for about half of marine microbial mortality.

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Background: The microbiome affects the health of plants and animals, including humans, and has many biological, ecological, and evolutionary consequences. Microbiome studies typically rely on sequencing ribosomal 16S RNA gene fragments, which serve as taxonomic markers for prokaryotic communities; however, for eukaryotic microbes this approach is compromised, because 18S rRNA gene sequences from microbial eukaryotes are swamped by contaminating host rRNA gene sequences.

Results: To overcome this problem, we developed CRISPR-Cas Selective Amplicon Sequencing (CCSAS), a high-resolution and efficient approach for characterizing eukaryotic microbiomes.

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Neurolymphomatosis (NL) is a rare condition caused by the lymphomatous or leukemic infiltration of nerves and manifests as neuropathy. Most often, NL is associated with B-lineage non-Hodgkin lymphoma (NHL) and only infrequently occurs in conjunction with T- or NK-lineage NHL. Extranodal NK/T-cell lymphoma (ENKTL)-associated NL is exceedingly unusual, with only 9 cases described in the English language literature, in addition to our case.

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Pacific oyster , endemic to coastal Asia, has been translocated globally throughout the past century, resulting in self-sustaining introduced populations (naturalized). Oyster aquaculture industries in many parts of the world depend on commercially available seed (hatchery-farmed) or naturalized/wild oysters to move onto a farm (naturalized-farmed). It is therefore important to understand genetic variation among populations and farm types.

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Myoclonic jerks and inattentiveness may be rare neurologic complications of ATO toxicity. Clinicians must be aware of this rare toxicity given that the ATO and ATRA combination is now standard-of-care treatment of low-risk APL.

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Glioblastoma multiforme (GBM) is an aggressive tumour that can lead to lymphopaenia. Its standard treatment involves temozolomide (TMZ) chemotherapy with radiation, often with addition of corticosteroids for symptomatic management. Although TMZ is also immunosuppressive, patients receiving TMZ rarely develop disseminated opportunistic infections.

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Background: Given its rare incidence, there are few epidemiological case series on paraneoplastic neurologic syndromes (PNS).

Methods: We present a 10-year series compiled in the Section of Neuro-Oncology, Yale Cancer Center between 2002 and 2012.

Results: Twenty-five cases met the PNS Euro-network criteria for definitive PNS.

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Purpose: To report the incidence and outcomes of intraoperative Descemet membrane (DM) perforations during deep anterior lamellar keratoplasty (DALK).

Design: Retrospective, consecutive, interventional case series.

Methods: A retrospective audit of all DALK cases performed from 2004 to 2015 in a tertiary center, with and without intraoperative DM perforations.

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Prasinophytes are widespread marine algae for which responses to nutrient limitation and viral infection are not well understood. We studied the picoprasinophyte, Micromonas pusilla, grown under phosphate-replete (0.65 ± 0.

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The following protocol describes the isolation and purification of viruses infecting cyanobacteria using a liquid bioassay approach. Viruses infecting cyanobacteria are also known as cyanophages. This protocol was written specifically for the isolation of cyanophages infecting freshwater cyanobacteria particularly, cyanobacteria that cannot be cultured on solid media.

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The beluga whale is a cetacean that inhabits arctic and subarctic regions, and is the only living member of the genus . The genome of the beluga whale was determined using DNA sequencing approaches that employed both microfluidic partitioning library and non-partitioned library construction. The former allowed for the construction of a highly contiguous assembly with a scaffold N50 length of over 19 Mbp and total reconstruction of 2.

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Prasinophytes, a group of eukaryotic phytoplankton, has a global distribution and is infected by large double-stranded DNA viruses (prasinoviruses) in the family . This study examines the genetic repertoire, phylogeny, and environmental distribution of phycodnaviruses infecting , other prasinophytes and chlorophytes. Based on comparisons among the genomes of viruses infecting and other phycodnaviruses, as well as the genome from a host isolate of , viruses infecting (MpVs) share a limited set of core genes, but vary strongly in their flexible pan-genome that includes numerous metabolic genes, such as those associated with amino acid synthesis and sugar manipulation.

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Introduction: Chloral hydrate (CH) sedation is routinely used in paediatric ophthalmic examination in Singapore as an alternative to examination under general anaesthesia. Despite CH's traditionally high success rates and relatively low rate of adverse events, there is little data on its safety and efficacy as a sedative for ophthalmic procedures in an Asian population.

Materials And Methods: A retrospective chart review was performed, including children who underwent CH sedation at the Singapore National Eye Centre from January 2012 to January 2015.

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Modern microbialites are complex microbial communities that interface with abiotic factors to form carbonate-rich organosedimentary structures whose ancestors provide the earliest evidence of life. Past studies primarily on marine microbialites have inventoried diverse taxa and metabolic pathways, but it is unclear which of these are members of the microbialite community and which are introduced from adjacent environments. Here we control for these factors by sampling the surrounding water and nearby sediment, in addition to the microbialites and use a metagenomics approach to interrogate the microbial community.

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Viruses are the most common biological entities in the marine environment. There has not been a global survey of these viruses, and consequently, it is not known what types of viruses are in Earth's oceans or how they are distributed. Metagenomic analyses of 184 viral assemblages collected over a decade and representing 68 sites in four major oceanic regions showed that most of the viral sequences were not similar to those in the current databases.

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The purpose of this study was to characterize Vibrio parahaemolyticus viruses (VpVs) isolated from different environments within and adjacent to the Strait of Georgia, and to examine the relative influences of distance and environment on host-range and genetic richness. Nearly all seawater enrichment cultures (29/31) generated isolates, implying that VpVs were widespread in the virioplankton, yet at low abundances (< 1 l(-1)). Viruses were not detected in sediments (n = 99).

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Synopsis of recent research by authors named "Amy M Chan"

  • - Amy M Chan's recent research predominantly focuses on the microbiomes of Pacific oysters, exploring how various factors such as age, ocean warming, and environmental stressors impact their microbial communities and overall health.
  • - Chan's work also emphasizes the importance of genetic diversity in oyster populations for broodstock management, reflected in the development of a high-throughput amplicon panel for efficient genotyping of Pacific oysters.
  • - Additionally, her studies investigate the dynamics of marine microbial communities, including taxon-specific interactions and the role of viral lysis in microbial mortality, enhancing our understanding of microbial ecology in marine environments.