The Medicine Wheel: informing the management of tuberculosis outbreaks in Indigenous communities

ABSTRACTMany Indigenous communities in Canada experience endemic tuberculosis with superimposed periodic epidemic outbreaks. Failures in outbreak management have resulted in the “seeding” of future infection and disease. In this paper we present a model that may be used in planning, implementation and review of tuberculosis outbreak management in Cree Indigenous communities in Canada, based on the Medicine Wheel, a paradigm for holistic living. In the context of tuberculosis management, the Medicine Wheel provides a path for the establishment of respectful cross-cultural relationships, the expression of values through action, true community engagement and partnership, and the establishment of culture-based processes of transparency, accountability and change

Abstract TMP43: Routine Labs may Help Predict tPA-related Hemorrhagic Transformation: A Role for Serial Monitoring of Prothrombin Time (PT) and Partial Thromboplastin Time (PTT) Post tPA

Background: Intravenous tissue plasminogen activator (tPA) is not routinely followed by blood work due to its reputed short half-life. While there has been a great deal of research on tPA’s extra-vascular effects on the neurovascular unit in the context of hemorrhagic complications, there is little clinical data on the intravascular efficacy of IV tPA - how and where it has its intended effect. Emerging data suggest that tPA may be most effective in the microvasculature and IV therapy may be a good adjunct to intra-arterial (IA) therapy. We previously found through proteomic profiling that the effects of IV tPA can last more than 72 hours. Now, we report that even routine blood labs can potentially help predict hemorrhagic transformation (HT). Method: 72 stroke patients treated with IV tPA were recruited post IRB approval. Clinical coagulation profiles (PT, PTT, fibrinogen and D-dimer) were performed at 12, 24, 72 hrs post IV tPA. Patients on medications (e.g. anticoagulants) or having other conditions (e.g. liver dysfunction, infection) that may affect these labs were excluded. Result: Compared to patients without HT, HT patients had significantly higher PT and PTT (Fig. 1 A,B) as early as 12 hrs post tPA administration and throughout the first 3 days of treatment. ROC analysis suggested PT and PTT at 12 and 24 hrs have potential to predict tPA-induced HT (Figure 1C,D. PT: AUC = 0.848, p = 0.001; PTT: AUC = 0.877; p = 0.003). Conclusion: Higher PT and PTT levels within 72 hours of IV tPA are early markers of HT post IV tPA in acute ischemic stroke. Whether these routine labs have value in symptomatic hemorrhage will require further study in a larger cohort. But this proof-of-concept study suggests that tPA efficacy can potentially be followed in real time, even with routine labs. The development of a reliable blood test would be of clinical utility to gauge thrombolytic efficacy in real time to guide and/or triage adjunct treatments. </jats:p

Old Keyam – A Framework for Examining Disproportionate Experience of Tuberculosis Among Aboriginal Peoples of the Canadian Prairies

On the Canadian Prairies, First Nations and Métis peoples are disproportionately affected by tuberculosis (TB) compared to other Canadians. Statistics show enduring transmission and high rates of active TB disease. Despite awareness of the social determinants of TB transmission—such as substance abuse, comorbidities, and basic needs being unmet—transmission and outbreaks continue to occur among Aboriginal people. The Determinants of Tuberculosis Transmission project is a mixed methods, interdisciplinary study that used quantitative questionnaires and qualitative interviews to look more closely at patients’ experiences of TB. Provincial Network Committees (PNCs) comprised of Elders, traditionalists, community-based TB workers, and health researchers in three participating provinces guided the project from inception through to data analysis, interpretation, and dissemination. The collaborative efforts of the patients, the research team, and the PNCs uncovered a continuing influence of colonization in TB transmission. Overwhelming feelings of apathy and despair for the hold that TB continues to have in the lives of patients, families, and communities is captured by the Cree word “keyam,” which may be translated as “to give up” or to ask, “What is the use?” This paper explores the concept of keyam in relation to TB transmission

Abstract TP426: PFO Closure Reduces Plasma Levels of Serotonin in Long Term Follow up of Stroke Patients

Background: PFO allows venous clots and vasoactive circulatory factors to bypass pulmonary filtration and remain in circulation. Serotonin (5-HT) has procoagulant and oxidative roles in both cardiovascular and neurovascular injury. We previously identified an immediate reduction of 5-HT in left atrial blood post PFO closure. To understand the long-term effect of PFO closure, we report the changes of 5-HT in peripheral venous blood in 1-year follow-up. Method: 97 PFO-related stroke patients were recruited in accordance with IRB. Venous blood was collected at baseline (BL) and 1 year follow-up (FU) post treatment (PFO closure or medical therapy). Plasma 5-HT was quantified by mass spectrometry. Patients with serotonin modifying medications (e.g. SSRIs) or conditions (e.g. anxiety/depression) were excluded. Result: 5-HT concentration in peripheral venous blood was significantly reduced by 27.27% (BL: 7.57 ± 8.04 μmol/l; FU: 5.51 ± 5.72 μmol/l; p = 0.0034) in 61 patients receiving PFO closure (Fig 1A). In the 37 PFO patients treated with medical therapy alone, no changes were observed (5-HT: BL: 5.79 ± 7.15 μmol/l; FU: 6.25 ± 6.68 μmol/l; p = 0.4050) (Fig 1B). This decrease in serotonin was independently associated with PFO closure after adjusting for age, gender, medical history and medication status in a multivariate regression (Fig 1C). Conclusion: We found that PFO closure independently reduced 5-HT level in peripheral venous blood. These results support the hypothesis that PFO associated right-to-left interatrial shunting may foster higher levels of procoagulant and vasoactive substances in circulation. We have previously found PFO closure to decrease prothrombotic markers immediately post closure; this effect is now shown also to be sustained in long term follow-up up to 1 year. Further studies are ongoing on the clinical outcome of these PFO related stroke patients with respect to their prothrombotic circulatory profiles. </jats:p

Therapeutic Potential of Targeted HOXA-TALE Knockdown in AML,

Abstract Abstract 3460 HOX genes are master regulators of hematopoietic stem and progenitor cell (HSPC) development. HOX interaction with TALE (PBX or MEIS) proteins is pivotal to their function. The prevailing hypothesis is that HOX/TALE expression underlies HSPC self-renewal while dysregulated HOX/TALE expression underpins maintenance of the leukemia initiating cell. Expression profiling studies support this hypothesis and highlight the importance of the HOXA cluster and TALE genes in hematopoiesis and leukemogenesis. The aim of this study was to identify and target clinically relevant HOX and TALE genes in AML cells representative of the particular disease subtype. HOXA cluster and leukemia-associated TALE gene expression was evaluated in 166 favourable and intermediate AML patient samples by Affymetrix microarray and expression of the significantly different genes was confirmed by RQ-PCR assays in an independent patient cohort. HOXA1-A2, A4-A10, PBX3 and MEIS1 displayed significant differential expression (p'0.01) between favourable and intermediate AML subgroups and confirmed an association of HOXA/TALE with nucleophosmin gene mutations (NPM1-mut) previously identified as a favourable prognostic marker in AML. HOXA9 was shown to be differentially expressed and HOXA6 was identified as the most consistently and highly expressed member of the previously reported ‘HOX code' by microarray analysis. These two HOX genes together with MEIS1 and PBX3 were selected for further study. Immunoprecipitation assays identified HOXA6/9-PBX3-MEIS1 protein interactions in AML cell lines demonstrating potential functional benefit of targeting members of these complexes in the disease setting. The HOXA/TALE axis was targeted in OCI AML3 (NPM1-mut) and U937 (NPM1-WT) AML cells using specific shRNAs (at least two per target) with Nucleofection or viral delivery followed by puromycin selection. Knockdown was validated by RQ-PCR as greater than 70% and western blotting where compatible antibodies were available. Cell viability was assessed using CellTiter-Glo® and direct cell counting whilst cell death was determined using the Caspase-Glo™assay. Cell responses were examined following targeted single gene knockdown of HOXA6, HOXA9, MEIS1 and PBX3, dual knockdown of HOXA6+HOXA9 either alone or in combination with standard-of-care therapeutic agents (Cytarabine or Mylotarg). Altered expression of genes associated with cell cycle and adhesion was identified following targeted gene knockdown using the Roche AmpliChip containing 1500 leukemia-associated probesets. Targeted reduction of HOXA6, HOXA9, MEIS1 PBX3 and combined HOXA6+HOXA9 levels greatly reduced cell growth compared to controls and was additive when combined with IC50 values of the chemotherapies used in the treatment of AML. This effect on cell growth may be due in part to increased apoptosis since increased caspase3/7 activity (up to 3.3 fold for PBX3 in U937 cells) was observed following HOX or TALE knockdown in either cell line. Furthermore, HOX or TALE knockdown resulted in impaired colony formation in both cell lines either due to reduction in number, size or metabolic activity compared to non-silenced controls. In addition, altered cell morphology with reduced blast-like features, was observed by HOXA6, HOXA9, MEIS1 or PBX3 knockdown in both cell lines. Together the data support a key role for HOX-TALE in AML and demonstrate dependency on this axis in leukemia maintenance. In summary, HOXA/TALE knockdown impairs growth and sensitises leukemic cells to chemotherapy independent of NPM1 mutation status. These findings suggest targeting of clinically significant HOXA cluster genes and their critical co-factors or modulation of downstream pathways could offer a novel strategy in the treatment of AML. Disclosures: No relevant conflicts of interest to declare. </jats:sec

“Finally when I started falling down”: Indigenous tuberculosis patient experiences of health and illness on the Canadian prairies

This paper adds evidence to a growing body of literature seeking to understand the disproportionate occurrence of tuberculosis (TB) in Indigenous populations of Canada and reveals insights that may inform effective interventions. As a disease, TB is recognized as a disorder of the body, for which there are successful treatments. Its persistence in some populations, however, requires an understanding of TB as an illness, whereby disease is shaped into behaviours and experiences. Fifty-five self-identified Indigenous participants with infectious pulmonary TB completed a questionnaire and an interview as part of the Determinants of Tuberculosis Transmission (DTT) project. Questionnaire data report on sociodemographic information and exposure to TB risk factors, while interview data describe participants’ experiences of TB within the context of their personal histories and everyday lives. Analysis showed that TB symptoms did not stand out as unusual in the everyday life and health experiences of participants. State of health and decisions about accessing healthcare were associated with socioeconomic deprivation, as well as negative experiences connected with historical and contemporary impacts of colonization. The “tipping point” concept effectively captures the shift in health that pushes participants to seek healthcare. Family, friends, and other caregivers are important influences and need to be part of the effort to avoid advanced TB illness and stop the cycle of transmission. More significantly, there is a need to address the structures and systems that produce and perpetuate life conditions that result in a usual state of compromised health.</jats:p

“Finally when I started falling down”: Indigenous tuberculosis patient experiences of health and illness on the Canadian prairies

This paper adds evidence to a growing body of literature seeking to understand the disproportionate occurrence of tuberculosis (TB) in Indigenous populations of Canada and reveals insights that may inform effective interventions. As a disease, TB is recognized as a disorder of the body, for which there are successful treatments. Its persistence in some populations, however, requires an understanding of TB as an illness, whereby disease is shaped into behaviours and experiences. Fifty-five self-identified Indigenous participants with infectious pulmonary TB completed a questionnaire and an interview as part of the Determinants of Tuberculosis Transmission (DTT) project. Questionnaire data report on sociodemographic information and exposure to TB risk factors, while interview data describe participants’ experiences of TB within the context of their personal histories and everyday lives. Analysis showed that TB symptoms did not stand out as unusual in the everyday life and health experiences of participants. State of health and decisions about accessing healthcare were associated with socioeconomic deprivation, as well as negative experiences connected with historical and contemporary impacts of colonization. The “tipping point” concept effectively captures the shift in health that pushes participants to seek healthcare. Family, friends, and other caregivers are important influences and need to be part of the effort to avoid advanced TB illness and stop the cycle of transmission. More significantly, there is a need to address the structures and systems that produce and perpetuate life conditions that result in a usual state of compromised health