Reconciling traditional knowledge, food security, and climate change: experience from Old Crow, YT, Canada.

BACKGROUND: Because of a lack of transportation infrastructure, Old Crow has the highest food costs and greatest reliance on traditional food species for sustenance of any community in Canada's Yukon Territory. Environmental, cultural, and economic change are driving increased perception of food insecurity in Old Crow. OBJECTIVES: To address community concerns regarding food security and supply in Old Crow and develop adaptation strategies to ameliorate their impact on the community. METHODS: A community adaptation workshop was held on October 13, 2009, in which representatives of different stakeholders in the community discussed a variety of food security issues facing Old Crow and how they could be dealt with. Workshop data were analyzed using keyword, subject, and narrative analysis techniques to determine community priorities in food security and adaptation. RESULTS: Community concern is high and favored adaptation options include agriculture, improved food storage, and conservation through increased traditional education. These results were presented to the community for review and revision, after which the Vuntut Gwitchin Government will integrate them into its ongoing adaptation planning measures.

Proteomic analysis of eccrine sweat: implications for the discovery of schizophrenia biomarker proteins.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and multiple reaction monitoring mass spectrometry (MRM-MS) proteomics analyses were performed on eccrine sweat of healthy controls, and the results were compared with those from individuals diagnosed with schizophrenia (SZ). This is the first large scale study of the sweat proteome. First, we performed LC-MS/MS on pooled SZ samples and pooled control samples for global proteomics analysis. Results revealed a high abundance of diverse proteins and peptides in eccrine sweat. Most of the proteins identified from sweat samples were found to be different than the most abundant proteins from serum, which indicates that eccrine sweat is not simply a plasma transudate and may thereby be a source of unique disease-associated biomolecules. A second independent set of patient and control sweat samples were analyzed by LC-MS/MS and spectral counting to determine qualitative protein differential abundances between the control and disease groups. Differential abundances of selected proteins, initially determined by spectral counting, were verified by MRM-MS analyses. Seventeen proteins showed a differential abundance of approximately 2-fold or greater between the SZ pooled sample and the control pooled sample. This study demonstrates the utility of LC-MS/MS and MRM-MS as a viable strategy for the discovery and verification of potential sweat protein disease biomarkers.

Community-based health research led by the Vuntut Gwitchin First Nation.

OBJECTIVES: This paper documents an exceptional research partnership developed between the Vuntut Gwitchin Government (VGG) in Old Crow, Yukon, with a group of scientists to examine northern food security and health as part of a larger, multidisciplinary International Polar Year (IPY) research program. We focus on the elements that enabled a successful community-researcher relationship. Study design. The VGG led the development of the research and acted as Principal Investigator on the IPY grant. The multidisciplinary collaboration spanned the physical, biological and health sciences, including issues related to food security. METHODS: The food security and health component of this research was carried out using a series of complementary methods, including focus groups, structured interviews, a household questionnaire, an interactive workshop, community meetings, transcript analysis and a caribou flesh exposure assessment. RESULTS: Results from the food security component are informing local and regional adaptation planning. The legacy of the research collaboration includes a number of results-based outputs for a range of stakeholders, a community-based environmental monitoring program, long-term research relationships and improved community capacity. CONCLUSIONS: The type of collaboration described here provides a useful model for new types of participatory health research with northern communities.

Mild cognitive impairment: prodromal Alzheimer's disease or something else?

The majority of mild cognitive impairment (MCI) studies use baseline and one follow-up measurement to determine the clinical course of the disorder. This report of MCI clinical course is based on the a statistical evaluation of multiple neurocognitive tests over a 60 month period in elderly normal and MCI cohorts. The data includes serial informant-based measures (Clinical Dementia Rating [CDR]) and a comprehensive battery of neuropsychological tests analyzed by two different regression methods. Twenty-nine elderly participants entered the study as neurocognitively normal; 26 remained normal, 2 progressed to MCI, and 1 progressed to dementia. Eighty-three participants entered the study as multiple domain MCI cases; 10 became normal, 46 remained MCI, and 27 progressed to dementia. Three of the 27 demented died with full necropsies performed (one case was progressive supranuclear palsy and two confirmed Alzheimer's disease with severe cerebral amyloid angiopathy (CAA)). Without serial measures, 1 in 8 MCI could be misclassified as "stable MCI" despite reverting to normal. The stable MCI cohorts did not benefit from practice effects though the normal subjects did. Applying Classification and Regression Tree (CART) analysis enabled prediction of the endpoint status of participants from baseline values with 78.6% accuracy. The fluctuating cognitive status of the multiple domain MCI cases implies a remitting pathologic process with elements of recovery consistent with a progressive microvasculopathy such as CAA.

Assessing risk of mercury exposure and nutritional benefits of consumption of caribou (Rangifer tarandus) in the Vuntut Gwitchin First Nation community of Old Crow, Yukon, Canada.

The contamination of traditional foods with chemical pollutants is a challenge to the food security of Aboriginal Peoples. Mercury levels are generally low in terrestrial animals; however renal mercury levels have been shown to change over time in the Porcupine Caribou Herd, the principal food source for the Vuntut Gwitchin First Nation of Old Crow in Yukon, Canada. Seventy-five Porcupine Caribou muscle, sixty-three kidney and three liver samples were analyzed for total mercury. Average concentrations were 0.003, 0.360 and 0.120mg/kg wet weight total mercury for muscle, kidney and liver, respectively. Consumption data of caribou muscle, kidney and liver were collected from twenty-six adults in Vuntut Gwitchin households. Women of child-bearing age (n=5) consumed a median of 71.5g/person/day of caribou muscle and 0.0g/person/day kidney but consumed no liver; median consumptions for all other adults (women aged 40+ and all men, n=21) were 75.8, 3.2 and 2.5g/person/day for meat, kidney and liver, respectively. Median dietary exposures to total mercury from caribou tissues were estimated to be 0.138µg/kg body weight for women of child-bearing age and 0.223µg/kg body weight for other adults. Caribou tissues were found to contribute high levels of important nutrients to the diet and pose minimal health risk from mercury exposure.

Importance of traditional foods for the food security of two First Nations communities in the Yukon, Canada.

OBJECTIVES: This study sought to evaluate food consumption patterns in the context of food security in two Yukon First Nations communities. STUDY DESIGN: Twenty-nine members of Vuntut Gwitchin households in Old Crow and 33 members of Tlingit households in Teslin participated in individual interviews. METHODS: Food frequency questionnaires were used to quantify traditional food consumption throughout the spring 2007 and winter 2008 and to identify potential temporal trends through a comparison with data from the early 1990s. Additional questions, including the Health Canada Household Food Security Survey Module, sought to assess food security concerns in each community. RESULTS: Overall frequency of traditional food consumption did not change in either community from the 2 time-point analyses. There was, however, a difference in frequency of consumption of certain groups of foods, and this highlighted the degree to which environmental variability affects the availability of foods. CONCLUSION: The importance of traditional foods in the diet of Yukon First Nations has not changed over the past 15 years. However, limited availability of food species, access to harvesting equipment and decrease in available time to go out on the land to harvest are food security challenges facing households today.

The heme degradation pathway is a promising serum biomarker source for the early detection of Alzheimer's disease.

One of the remaining challenges in Alzheimer's disease (AD) research is the establishment of biomarkers for early disease detection. As part of a prospective study spanning a period of five years, we have collected serial serum samples from cognitively normal, mild cognitively impaired (MCI), and mild AD participants, including same patient samples before and after cognitive decline. Using mass spectrometry we identified several promising leads for biomarker development, such as prosaposin, phospholipase D1, biliverdin reductase B, and S100 calcium binding protein A7. Selected candidate markers were verified using reverse phase protein microarray assays. Of 15 protein/protein abundance ratios that were significantly altered in sera from subjects with mild AD compared to Normal or MCI subjects, 14 were composed of ratios containing heme oxygenase-1, biliverdin reductase A, or biliverdin reductase B. Moreover, an increase in the protein abundance ratio of matrix metallopeptidase 9/biliverdin reductase differentiated stable MCI subjects from MCI subjects progressing into mild AD before the onset of cognitive decline. These findings strongly implicate the heme degradation pathway as a promising source of protein biomarkers for the early detection of AD.

Serial susceptibility weighted MRI measures brain iron and microbleeds in dementia.

A new iron sensitive MR sequence (susceptibility weighted imaging - SWI) enabling the simultaneous quantitation of regional brain iron levels and brain microbleeds (BMB) has been acquired serially to study dementia. Cohorts of mildly cognitively impaired (MCI) elderly (n = 73) and cognitively normal participants (n = 33) have been serially evaluated for up to 50 months. SWI phase values (putative iron levels) in 14 brain regions were measured and the number of BMB were counted for each SWI study. SWI phase values showed a left putaminal mean increase of iron (decrease of phase values) over the study duration in 27 participants who progressed to dementia compared to Normals (p = 0.035) and stable MCI (p = 0.01). BMB were detected in 9 out of 26 (38%) MCI participants who progressed to dementia and are a significant risk factor for cognitive failure in MCI participants [risk ratio = 2.06 (95% confidence interval 1.37-3.12)]. SWI is useful to measure regional iron changes and presence of BMB, both of which may be important MR-based biomarkers for neurodegenerative diseases.

Increased production of inflammatory cytokines in mild cognitive impairment.

Recent studies indicate that chronic inflammation plays a pathogenic role in both the central nervous system (CNS) and periphery in Alzheimer's disease (AD). We have screened for cytokines differentially produced by peripheral blood mononuclear cells (PBMCs) isolated from subjects with mild cognitive impairment (MCI) and mild AD subjects who had progressed from MCI using a commercially available cytokine array. Following determination of expressed cytokines, we quantified levels of the proinflammatory cytokines TNF-alpha, IL-6, and IL-8, and the anti-inflammatory cytokine IL-10 using flow cytometry. We have found a significant increase in the levels of IL-6, IL-8, and IL-10 produced by PBMCs stimulated for 24 h with phytohemagglutinin (PHA) in MCI subjects compared to healthy elderly controls. However, in PBMCs stimulated for 48 h with lipopolysaccharide (LPS), lower TNF-alpha/IL-10, IL-6/IL-10, and IL-8/IL-10 ratios were seen in MCI subjects. There were no differences in plasma levels of IL-8 between aged controls, MCI, and mild AD, and the levels of circulating IL-6 and IL-10 were below detection limits. Our data indicate that changes in cytokine production by PBMCs may be detected early in MCI, and an alteration of the immune response may precede clinical AD.

Local observations of climate change and impacts on traditional food security in two northern Aboriginal communities.

OBJECTIVES: Our primary objective was to record participant observations of changes in the local environment, harvesting situations and traditional food species and to explore what impact these may have on traditional food. STUDY DESIGN: A participatory study with 2 northern Aboriginal communities in Canada. METHODS: Focus groups were conducted in both communities. Both specific and open-ended questions were asked, to gather information about the traditional food harvest and a qualitative analysis was conducted. RESULTS: Members from both communities are witnessing variable changes in climate that are affecting their traditional food harvest. New species and changes in migration of species being observed by community members have the potential to affect the consumption of traditional food. Similarly, changes in water levels in and around harvesting areas are affecting access to harvest areas, which in turn affects the traditional food harvest. CONCLUSIONS: Community members have been required to change their harvest mechanisms to adapt to changes in climate and ensure an adequate supply of traditional food. A strong commitment to programs that will ensure the protection of traditional food systems is necessary.

A multicenter study of permanent hemodialysis access patency: beneficial effect of clipped vascular anastomotic technique.

OBJECTIVE: There is an urgent and compelling need to reduce the morbidity and expense of maintaining hemodialysis vascular access patency. This large, long-term, retrospective, multicenter study, which compared access patency of autogenous arteriovenous fistulas (AVF) and synthetic bridge grafts (AVG) created with conventional sutures or nonpenetrating clips, was undertaken to resolve conflicting results from previous smaller studies. DESIGN: Patency data for 1385 vascular access anastomoses (clipped or sutured) was obtained from 17 hospitals and dialysis centers (Appendix). Five hundred eighteen AVF (242 clip, 276 suture) and 827 AVG (440 clip, 384 suture) were analyzed. Statistical comparisons were made with Kaplan-Meier survival analysis, log-rank test, two-sample t test, and X(2) test. The Cox proportional hazards model was used to confirm Kaplan-Meier analysis. RESULTS: Access patency (primary, secondary, overall, and intention to treat) was significantly improved in access anastomoses constructed with clips. In the intention-to-treat group, primary patency at 24 months was 0.54 for clipped AVF and 0.34 for sutured AVF, and was 0.36 for clipped AVG and 0.17 for sutured AVG. At 24 months, primary patency rate for AVF successfully used for dialysis was 0.67 for clips and 0.48 for sutures, and for AVG was 0.39 for clips and 0.19 for sutured constructs. Interventions necessary to maintain patency were significantly fewer in clipped anastomoses. CONCLUSION: Replacing conventional suture with clips significantly reduces morbidity associated with maintaining permanent hemodialysis vascular access. This beneficial effect may be due to the biologic superiority of interrupted, nonpenetrating vascular anastomoses.