Recurrent Mutations of T-Cell Receptor and CO-Stimulatory Signaling Proteins in Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) comprise a heterogeneous group of mature T-cell neoplasms with a poor prognosis. Recently, mutations in TET2 and other epigenetic modifiers as well as RHOA have been identified in these diseases, particularly in angioimmunoblastic T-cell lymphoma (AITL). CD28 is the major co-stimulatory receptor in T-cells which, upon binding ligand, induces sustained T-cell proliferation and cytokine production when combined with T-cell receptor stimulation, through many signaling molecules including VAV1. This thesis identifies recurrent mutations in CD28 in PTCLs, as well as mutations in VAV1. Two residues of CD28 – D124 and T195 – were recurrently mutated in 11.3% of cases of AITL and in one case of PTCL, not otherwise specified (PTCL-NOS). Surface plasmon resonance analysis of mutations at these residues with predicted differential partner interactions showed increased affinity for ligand CD86 (residue D124) and increased affinity for intracellular adaptor proteins GRB2 and GADS/GRAP2 (residue T195). Molecular modeling studies on each of these mutations suggested how these mutants result in increased affinities. We found increased transcription of the CD28-responsive genes CD226 and TNFA in cells expressing the T195P mutant in response to CD3 and CD86 co-stimulation and increased downstream activation of NF-κB by both D124V and T195P mutants. VAV1 mutations affect many important domains and may also enhance co-stimulatory signal. Together, these mutations suggest a novel potential pathway for therapeutic targeting in PTCLs

JOINT STIFFNESS IN OLD AND YOUNG RUNNERS DURING SHOD AND BAREFOOT RUNNING

The purpose of this study was to investigate the relationship between ankle and knee joint stiffness in barefoot and shod running. Fifteen old and 15 young individuals served as participants in this study. Joint kinematics and kinetics were collected while the participants ran overground in two running conditions: barefoot and shod. A quasi-joint stiffness was calculated using the quotient of the change in moment divided by the change in angle for the ankle and knee joints. A two-way ANOVA was conducted to asses ankle and knee joint stiffnesses. There were no interactions and no main effects for the knee joint stiffness. For the ankle joint, there was only a significant difference between conditions. These results indicate that in barefoot running, it is necessary to have a more compliant ankle to maintain the heel from touching the ground

AGE RELATED CHANGES IN LOWER EXTREMITY COORDINATION PATTERNS IN FEMALE RUNNERS

The aim of this study was to compare the coordination patterns of the lower extremity joints in older and younger females during running. The results of this study show that the older runners have maintained similar movement and coordination patterns to younger runners as a result of years of running experience. The results in this study could provide researchers and clinicians the information necessary to develop shoe wear and orthotic devices to reduce the risk of injury in specific populations

Real-time Telepathology Is Substantially Equivalent to In-Person Intraoperative Frozen Section Diagnosis

CONTEXT.—: Intraoperative diagnosis by frozen section is a mainstay of surgical pathology practice, providing immediate feedback to the surgical team. Despite good accuracy with modern methods, access to intraoperative surgical pathology with an appropriate turnaround time (TAT) has been a limiting factor for small or remote surgical centers, with negative impacts on cost and patient care. Telepathology offers immediate expert anatomic pathology consultation to sites without an in-house or subspecialized pathologist. OBJECTIVE.—: To assess the utility of live telepathology in frozen section practice. DESIGN.—: Frozen section diagnoses by telemicroscopy from 2 tertiary care centers with combined 3 satellite hospitals were queried for anatomic site, TAT per block, pathologist, and concordance with paraffin diagnosis. TAT and concordance were compared to glass diagnoses in the same period. RESULTS.—: For 748 intraoperative diagnoses by telemicroscopy, 694 had TATs with a mean of 18 minutes 56 seconds ± 8 minutes 45 seconds, which was slower than on glass (14 minutes 25 seconds ± 7 minutes 8 seconds, P \u3c .001). Twenty-two (2.89% of available) were discordant, which was not significantly different from the on-glass rate (P = .44) or categorical distribution (P = .31). Two cases (0.27%) had technical failures. CONCLUSIONS.—: Although in-person diagnoses were statistically faster, the great majority of telemicroscopic diagnoses were returned in less than 20 minutes. This remained true through numerous pathologists, pathology assistants and/or technicians, different hospitals, and during a combined 6 years. The concentration of discordant diagnoses among relatively few pathologists suggests individual comfort with telepathology and/or frozen section diagnosis. In rare cases, technologic issues prevented telemicroscopic diagnosis. Overall, this justifies continued use and expansion of telemicroscopic services in primary intraoperative diagnoses

A case study of the patient wait experience in an emergency department with therapy dogs

The quality of patient healthcare is a growing concern in Canada’s hospital emergency departments (ED) due to increasing wait times and associated adverse outcomes. A developing body of literature indicates that therapy dogs can positively impact the patient experience. In 2016, members of our team partnered with the Royal University Hospital (RUH) in Saskatchewan to become the first ED in Canada to integrate a visiting therapy dog to positively impact the patient wait experience. The aim of this preliminary case study was to examine if and how this unique initiative impacted patients’ feelings during their ED wait. A brief questionnaire was completed with one-hundred and twenty-four patients pre and post-therapy dog visit and a research observer documented the encounters. Quantitative and qualitative analysis of the data revealed that visiting with a therapy dog in the ED appeared to improve patients’ feelings. Specifically, patients’ perceived comfort levels increased and their distress levels decreased, and the encounters were considered by patients to be a welcome distraction from the stressful ED environment. Our team, comprised of clinicians, researchers, therapy dog handlers and patient advocates documented the advantages and challenges of implementing the initiative. The outcomes support further study of patients’ wait time experiences in the ED and the utility of a visiting therapy dog

Reducing Legionella Colonization of Water Systems with Monochloramine

Monochloramine reduced colonization in building hot water systems

FcγRIIb Inhibits Allergic Lung Inflammation in a Murine Model of Allergic Asthma

Allergic asthma is characterized by airway eosinophilia, increased mucin production and allergen-specific IgE. Fc gamma receptor IIb (FcγRIIb), an inhibitory IgG receptor, has recently emerged as a negative regulator of allergic diseases like anaphylaxis and allergic rhinitis. However, no studies to date have evaluated its role in allergic asthma. Our main objective was to study the role of FcγRIIb in allergic lung inflammation. We used a murine model of allergic airway inflammation. Inflammation was quantified by BAL inflammatory cells and airway mucin production. FcγRIIb expression was measured by qPCR and flow cytometry and the cytokines were quantified by ELISA. Compared to wild type animals, FcγRIIb deficient mice mount a vigorous allergic lung inflammation characterized by increased bronchoalveolar lavage fluid cellularity, eosinophilia and mucin content upon ragweed extract (RWE) challenge. RWE challenge in sensitized mice upregulated FcγRIIb in the lungs. Disruption of IFN-γ gene abrogated this upregulation. Treatment of naïve mice with the Th1-inducing agent CpG DNA increased FcγRIIb expression in the lungs. Furthermore, treatment of sensitized mice with CpG DNA prior to RWE challenge induced greater upregulation of FcγRIIb than RWE challenge alone. These observations indicated that RWE challenge upregulated FcγRIIb in the lungs by IFN-γ- and Th1-dependent mechanisms. RWE challenge upregulated FcγRIIb on pulmonary CD14+/MHC II+ mononuclear cells and CD11c+ cells. FcγRIIb deficient mice also exhibited an exaggerated RWE-specific IgE response upon sensitization when compared to wild type mice. We propose that FcγRIIb physiologically regulates allergic airway inflammation by two mechanisms: 1) allergen challenge mediates upregulation of FcγRIIb on pulmonary CD14+/MHC II+ mononuclear cells and CD11c+ cells by an IFN-γ dependent mechanism; and 2) by attenuating the allergen specific IgE response during sensitization. Thus, stimulating FcγRIIb may be a therapeutic strategy in allergic airway disorders

Do Frogs Get Their Kicks on Route 66? Continental U.S. Transect Reveals Spatial and Temporal Patterns of Batrachochytrium dendrobatidis Infection

The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been devastating amphibians globally. Two general scenarios have been proposed for the nature and spread of this pathogen: Bd is an epidemic, spreading as a wave and wiping out individuals, populations, and species in its path; and Bd is endemic, widespread throughout many geographic regions on every continent except Antarctica. To explore these hypotheses, we conducted a transcontinental transect of United States Department of Defense (DoD) installations along U.S. Highway 66 from California to central Illinois, and continuing eastward to the Atlantic Seaboard along U.S. Interstate 64 (in sum from Marine Corps Base Camp Pendleton in California to Naval Air Station Oceana in Virginia). We addressed the following questions: 1) Does Bd occur in amphibian populations on protected DoD environments? 2) Is there a temporal pattern to the presence of Bd? 3) Is there a spatial pattern to the presence of Bd? and 4) In these limited human-traffic areas, is Bd acting as an epidemic (i.e., with evidence of recent introduction and/or die-offs due to chytridiomycosis), or as an endemic (present without clinical signs of disease)? Bd was detected on 13 of the 15 bases sampled. Samples from 30 amphibian species were collected (10% of known United States' species); half (15) tested Bd positive. There was a strong temporal (seasonal) component; in total, 78.5% of all positive samples came in the first (spring/early-summer) sampling period. There was also a strong spatial component—the eleven temperate DoD installations had higher prevalences of Bd infection (20.8%) than the four arid (<60 mm annual precipitation) bases (8.5%). These data support the conclusion that Bd is now widespread, and promote the idea that Bd can today be considered endemic across much of North America, extending from coast-to-coast, with the exception of remote pockets of naïve populations

In vitro nuclear interactome of the HIV-1 Tat protein

<p>Abstract</p> <p>Background</p> <p>One facet of the complexity underlying the biology of HIV-1 resides not only in its limited number of viral proteins, but in the extensive repertoire of cellular proteins they interact with and their higher-order assembly. HIV-1 encodes the regulatory protein Tat (86–101aa), which is essential for HIV-1 replication and primarily orchestrates HIV-1 provirus transcriptional regulation. Previous studies have demonstrated that Tat function is highly dependent on specific interactions with a range of cellular proteins. However they can only partially account for the intricate molecular mechanisms underlying the dynamics of proviral gene expression. To obtain a comprehensive nuclear interaction map of Tat in T-cells, we have designed a proteomic strategy based on affinity chromatography coupled with mass spectrometry.</p> <p>Results</p> <p>Our approach resulted in the identification of a total of 183 candidates as Tat nuclear partners, 90% of which have not been previously characterised. Subsequently we applied <it>in silico </it>analysis, to validate and characterise our dataset which revealed that the Tat nuclear interactome exhibits unique signature(s). First, motif composition analysis highlighted that our dataset is enriched for domains mediating protein, RNA and DNA interactions, and helicase and ATPase activities. Secondly, functional classification and network reconstruction clearly depicted Tat as a polyvalent protein adaptor and positioned Tat at the nexus of a densely interconnected interaction network involved in a range of biological processes which included gene expression regulation, RNA biogenesis, chromatin structure, chromosome organisation, DNA replication and nuclear architecture.</p> <p>Conclusion</p> <p>We have completed the <it>in vitro </it>Tat nuclear interactome and have highlighted its modular network properties and particularly those involved in the coordination of gene expression by Tat. Ultimately, the highly specialised set of molecular interactions identified will provide a framework to further advance our understanding of the mechanisms of HIV-1 proviral gene silencing and activation.</p