The CNDR: Collaborating to translate new therapies for Canadians

Background: Patient registries represent an important method of organizing real world patient information for clinical and research purposes. Registries can facilitate clinical trial planning and recruitment and are particularly useful in this regard for uncommon and rare diseases. Neuromuscular diseases (NMDs) are individually rare but in aggregate have a significant prevalence. In Canada, information on NMDs is lacking. Barriers to performing Canadian multicentre NMD research exist which can be overcome by a comprehensive and collaborative NMD registry. Methods: We describe the objectives, design, feasibility and initial recruitment results for the Canadian Neuromuscular Disease Registry (CNDR). Results: The CNDR is a clinic-based registry which launched nationally in June 2011, incorporates paediatric and adult neuromuscular clinics in British Columbia, Alberta, Ontario, Quebec, New Brunswick and Nova Scotia and, as of December 2012, has recruited 1161 patients from 12 provinces and territories. Complete medical datasets have been captured on 460 index disease patients. Another 618 non-index patients have been recruited with capture of physician-confirmed diagnosis and contact information. We have demonstrated the feasibility of blended clinic and central office-based recruitment. Index disease patients recruited at the time of writing include 253 with Duchenne and Becker muscular dystrophy, 161 with myotonic dystrophy, and 71 with ALS. Conclusions: The CNDR is a new nationwide registry of patients with NMDs that represents an important advance in Canadian neuromuscular disease research capacity. It provides an innovative platform for organizing patient information to facilitate clinical research and to expedite translation of recent laboratory findings into human studies

Mutation in the Gene Encoding Ubiquitin Ligase LRSAM1 in Patients with Charcot-Marie-Tooth Disease

Charcot-Marie-Tooth disease (CMT) represents a family of related sensorimotor neuropathies. We studied a large family from a rural eastern Canadian community, with multiple individuals suffering from a condition clinically most similar to autosomal recessive axonal CMT, or AR-CMT2. Homozygosity mapping with high-density SNP genotyping of six affected individuals from the family excluded 23 known genes for various subtypes of CMT and instead identified a single homozygous region on chromosome 9, at 122,423,730–129,841,977 Mbp, shared identical by state in all six affected individuals. A homozygous pathogenic variant was identified in the gene encoding leucine rich repeat and sterile alpha motif 1 (LRSAM1) by direct DNA sequencing of genes within the region in affected DNA samples. The single nucleotide change mutates an intronic consensus acceptor splicing site from AG to AA. Direct analysis of RNA from patient blood demonstrated aberrant splicing of the affected exon, causing an obligatory frameshift and premature truncation of the protein. Western blotting of immortalized cells from a homozygous patient showed complete absence of detectable protein, consistent with the splice site defect. LRSAM1 plays a role in membrane vesicle fusion during viral maturation and for proper adhesion of neuronal cells in culture. Other ubiquitin ligases play documented roles in neurodegenerative diseases. LRSAM1 is a strong candidate for the causal gene for the genetic disorder in our kindred

Detecting the signature of permafrost thaw in Arctic rivers

Climate change induced permafrost thaw in the Arctic is mobilizing ancient dissolved organic carbon (DOC) in to headwater streams, however DOC exported from the mouth of major arctic rivers appears predominantly modern. Here we highlight that ancient (>20,000 ybp) permafrost-DOC is rapidly utilized by microbes (~50% DOC loss in <7 days), and that permafrost-DOC decay rates (0.12 to 0.19 d-1) exceed those for DOC in a major arctic river (Kolyma: 0.09 d-1). Permafrost-DOC exhibited unique molecular signatures, including high levels of aliphatics that were rapidly utilized by microbes. As microbes processed permafrost-DOC, its distinctive chemical signatures were degraded and converged towards those of DOC in the Kolyma River. The extreme biolability of permafrost-DOC and the rapid loss of its distinct molecular signature may explain the apparent contradiction between observed permafrost-DOC release to headwaters and the lack of a permafrost signal in DOC exported via major arctic rivers to the ocean

Defining a Leader Role curriculum for radiation oncology: A global Delphi consensus study

The need for radiation oncologists and other radiation oncology (RO) professionals to lead quality improvement activities and contribute to shaping the future of our specialty is self-evident. Leadership knowledge, skills and behaviours, like other competencies, can be learned (Blumenthal et al., 2012). The objective of this study was to define a globally applicable competency set specific to radiation oncology for the CanMEDS Leader Role (Frank et al., 2015). A modified Delphi consensus process delivering two rounds of on-line surveys was used. Participants included trainees, radiation/clinical oncologists and other RO team members (radiation therapists, physicists, and nurses), professional educators and patients. 72 of 95 (76%) invitees from nine countries completed the Round 1 (R1) survey. Of the 72 respondents to RI, 70 completed Round 2 (R2) (97%). In R1, 35 items were deemed for 'inclusion' and 21 for 'exclusion', leaving 41 'undetermined'. After review of items, informed by participant comments, 14 competencies from the 'inclusion' group went into the final curriculum; 12 from the 'undetermined' group went to R2. In R2, 6 items reached consensus for inclusion. This process resulted in 20 RO Leader Role competencies with apparent global applicability. This is the first step towards developing learning, teaching and assessment tools for this important area of trainin

Habitat-specific production of a fall line river shoal macroinvertebrate assemblage

Fall Line shoals are zones of geomorphic complexity within a river basin, and have been recognized as sites of high aquatic macroinvertebrate diversity and production. The shoals of the free-flowing Cahaba River, in central Alabama, represent some of the most significant remaining examples of this channel feature that was once common throughout many rivers of the southeastern United States prior to widespread river regulation. The goal of this dissertation is to examine how the major habitats of a Cahaba River shoal influence the distribution and secondary production of the macroinvertebrate assemblage. Chapter 2 quantifies the variety of habitat types across the shoal reach and examines the temporal biomass dynamics of the 2 most common in-stream macrophytes, Justicia americana and Podostemum ceratophyllum. Chapter 3 presents a new method for obtaining in situ growth rates of several species of the diverse pleurocerid snail assemblage. The results of this method were later used to estimate production for this family. Chapter 4 describes the distribution, biomass, and production of the nonnative Asiatic clam, Corbicula fluminea, across the shoal reach, highlighting its dependence on Justicia habitat. Finally, Chapter 5 incorporates the preceding chapters into a study of the distribution of macroinvertebrate assemblage production across bare bedrock, Justicia, and Podostemum habitats, as well as the entire shoal reach. Total annual production of all macroinvertebrates was 56.1 g AFDM m-2 y-1 in bedrock, 284.4 in Podostemum, and 177.3 in Justicia habitats. Total habitat-weighted production of the shoals reach was 87.1 g m-2 y-1, with bedrock contributing 24.3%, Podostemum 22.7%, and Justicia 53.0% to this total. This study supports the view that Fall Line shoals can support high habitat diversity and production, and that the more complex habitats (e.g., those with macrophytes) enhance benthic invertebrate diversity and production. Also, the influence of a given habitat depends largely on its relative abundance, and this study demonstrated that the Justicia habitat can have a dominant influence on diversity and production of a river reach. This work advances our understanding of the roles of shoal habitats in maintaining the diversity and function of this endangered river channel feature. (Published By University of Alabama Libraries

PIK3Cδ expression by fibroblasts promotes triple-negative breast cancer progression

As there is growing evidence for the tumor microenvironment’s (TME) role in tumorigenesis, we investigated the role of fibroblast-expressed kinases in triple negative breast cancer (TNBC). Using a high-throughput kinome screen combined with 3D invasion assays, we identified fibroblast-expressed PIK3Cδ (f-PIK3Cδ) as a key regulator of progression. Although PIK3Cδ was expressed in primary fibroblasts derived from TNBC patients, it was undetectable in breast cancer cell lines. Genetic and pharmacologic gain- and loss-of functions experiments verified the contribution of f-PIK3Cδ in TNBC cell invasion. Integrated secretomics and transcriptomics analyses revealed a paracrine mechanism via which f-PIK3Cδ confers its pro-tumorigenic effects. Inhibition of f-PIK3Cδ promoted the secretion of factors, including PLGF and BDNF, which led to upregulation of NR4A1 in TNBC cells where it acts as a tumor suppressor. Inhibition of PIK3Cδ in an orthotopic BC mouse model reduced tumor growth only after inoculation with fibroblasts, indicating a role of f-PIK3Cδ in cancer progression. Similar results were observed in the MMTV-PyMT transgenic BC mouse model, along with a decrease on tumor metastasis emphasizing the potential immune-independent effects of PIK3Cδ inhibition. Finally, analysis of BC patient cohorts and TCGA datasets identified f-PIK3Cδ (protein and mRNA levels) as an independent prognostic factor for overall and disease free survival, highlighting it as a therapeutic target for TNBC