Hospitalization for ambulatory care sensitive conditions among urban Métis adults.

BACKGROUND: Hospitalizations for ambulatory care sensitive conditions (ACSCs) are potentially preventable, but may be required if these conditions are not managed well. National-level information about ACSC hospitalizations is available for Canada, but not for Aboriginal groups. This study describes ACSC hospitalizations among urban Métis adults relative to their non-Aboriginal counterparts. DATA AND METHODS: The 2006/2007-to-2008/2009 Discharge Abstract Database, which contains hospitalization records from all acute care facilities (excluding Quebec), was linked to the 2006 Census to obtain Aboriginal identity information. Age-standardized ACSC hospitalization rates (ASHRs) per 100,000 population and rate ratios were calculated for Métis aged 18 to 74 relative to non-Aboriginal people of the same ages. Odds of ACSC hospitalizations were estimated using logistic regression models, adjusting for demographic, geographic, and socioeconomic characteristics. RESULTS: The ASHR for ACSCs among urban Métis adults was twice that among non-Aboriginal adults (393 versus 184 per 100,000 population). Even when demographic, geographic, and socioeconomic characteristics were taken into account, Métis had higher odds of ACSC hospitalizations overall (OR 1.5). Most commonly, these hospitalizations were for diabetes (OR 1.8) or chronic obstructive pulmonary disease (OR 1.5). Modelled factors partly reduced differences between Métis and non-Aboriginal adults, but variations between the groups remained after all adjustments. INTERPRETATION: Rates of ACSC hospitalizations were higher among Métis than among non-Aboriginal adults who lived in urban areas. Further research using other data sources is warranted to assess the roles of factors not available for this analysis, such as primary care, co-morbidity, and health behaviours.

Mycobacterium tuberculosis UvrB Is a Robust DNA-Stimulated ATPase That Also Possesses Structure-Specific ATP-Dependent DNA Helicase Activity.

Much is known about the Escherichia coli nucleotide excision repair (NER) pathway; however, very little is understood about the proteins involved and the molecular mechanism of NER in mycobacteria. In this study, we show that Mycobacterium tuberculosis UvrB (MtUvrB), which exists in solution as a monomer, binds to DNA in a structure-dependent manner. A systematic examination of MtUvrB substrate specificity reveals that it associates preferentially with single-stranded DNA, duplexes with 3' or 5' overhangs, and linear duplex DNA with splayed arms. Whereas E. coli UvrB (EcUvrB) binds weakly to undamaged DNA and has no ATPase activity, MtUvrB possesses intrinsic ATPase activity that is greatly stimulated by both single- and double-stranded DNA. Strikingly, we found that MtUvrB, but not EcUvrB, possesses the DNA unwinding activity characteristic of an ATP-dependent DNA helicase. The helicase activity of MtUvrB proceeds in the 3' to 5' direction and is strongly modulated by a nontranslocating 5' single-stranded tail, indicating that in addition to the translocating strand it also interacts with the 5' end of the substrate. The fraction of DNA unwound by MtUvrB decreases significantly as the length of the duplex increases: it fails to unwind duplexes longer than 70 bp. These results, on one hand, reveal significant mechanistic differences between MtUvrB and EcUvrB and, on the other, support an alternative role for UvrB in the processing of key DNA replication intermediates. Altogether, our findings provide insights into the catalytic functions of UvrB and lay the foundation for further understanding of the NER pathway in M. tuberculosis.

Trends in Métis-related health research (1980-2009): identification of research gaps.

OBJECTIVE: Several literature reviews have highlighted the under-representation of Métis in research regarding Aboriginal Peoples. However, to date, an in-depth examination of trends in Métis research has not been undertaken. This literature review aims to identify trends and gaps in Métis-related health/well-being research over the past three decades (1980-2009). METHODS: Health, medical and social sciences literature databases including Cochrane, CINAHL, Embase, Pubmed, PyschInfo, and Web of Science were searched for Métis-relevant peer-reviewed articles published between 1980 and 2009 via two search strategies: 1) using the terms "Métis," "mixed-blood" or "half-breed," and 2) using a combination of terms: (Aboriginal OR Indigenous OR native OR "First Nation" OR Indian) and (mixed OR European OR Caucasian OR white) and "Canada". Articles pertaining to the health/well-being of Métis in Canada were retained, coded and analyzed by study type/design, gender-specificity, geography, research topic, the extent to which Métis-specific breakdown of findings was provided, and methodological quality relating to validity and reliability of the study. RESULTS: Noteworthy strengths in Métis research were observed, including increasing attention to chronic diseases, diet/nutrition/physical activity, and maternal and child health; a trend towards increased presentation of Métis-specific results among pan-Aboriginal studies, and female-specific and qualitative studies; and an equitable focus on urban and rural areas. Gaps were seen in research related to environment/toxicology, genetics, health delivery/programming/policy, injury, mental health (MH)/addictions, social determinants of health, and violence/crime. In addition, a dearth of male-specific research was identified. Also, most articles were cross-sectional in design. Finally, despite an increase in Métis-related articles over the past three decades, a large proportion of articles remained pan-Aboriginal in nature and did not provide a Métis-specific breakdown of findings. With respect to methodological quality, nearly two thirds of all studies were of strong or moderate quality (cross-sectional studies), good quality (cohort/case-control studies) or acceptable quality (qualitative and mixed methods studies). CONCLUSION: Several gaps exist in Métis-related health/well-being research with respect to study type/design, gender-specificity, research topics, presentation of Métis-specific findings, and methodological quality. In addition to specific gaps, the overall limited number of research articles/studies needs to be recognized. These deficiencies could be alleviated by increasing targeted funding and support for Métis-related research, and removing barriers to Métis-specific research. Addressing gaps in Métis health research will enable identification of appropriate targets for intervention and, subsequently, design, development and evaluation of interventions to address Métis health disparities and their determinants.

Suicidal ideation among Métis adult men and women--associated risk and protective factors: findings from a nationally representative survey.

OBJECTIVE: To determine the prevalence of suicidal ideation among Métis men and women (20-59 years) and identify its associated risk and protective factors using data from the nationally representative Aboriginal Peoples Survey (2006). STUDY DESIGN: Secondary analysis of previously collected data from a nationally representative cross-sectional survey. RESULTS: Across Canada, lifetime suicidal ideation was reported by an estimated 13.3% (or an estimated 34,517 individuals) of the total population of 20-to-59-year-old Métis. Of those who ideated, 46.2% reported a lifetime suicide attempt and 6.0% indicated that they had attempted suicide in the previous 12 months. Prevalence of suicidal ideation was higher among Métis men than in men who did not report Aboriginal identity in examined jurisdictions. Métis women were more likely to report suicidal ideation compared with Métis men (14.9% vs. 11.5%, respectively). Métis women and men had some common associated risk and protective factors such as major depressive episode, history of self-injury, perceived Aboriginal-specific community issues, divorced status, high mobility, self-rated thriving health, high self-esteem and positive coping ability. However, in Métis women alone, heavy frequent drinking, history of foster care experience and lower levels of social support were significant associated risk factors of suicidal ideation. Furthermore, a significant interaction was observed between social support and major depressive episode. Among Métis men, history of ever smoking was the sole unique associated risk factor. CONCLUSION: The higher prevalence of suicidal ideation among Métis women compared with Métis men and the observed gender differences in associations with some associated risk and protective factors suggest the need for gender-responsive programming to address suicidal ideation.

An urban food store intervention positively affects food-related psychosocial variables and food behaviors.

Obesity and other diet-related chronic diseases are more prevalent in low-income urban areas, which commonly have limited access to healthy foods. The authors implemented an intervention trial in nine food stores, including two supermarkets and seven corner stores, in a low-income, predominantly African American area of Baltimore City, with a comparison group of eight stores in another low-income area of the city. The intervention (Baltimore Healthy Stores; BHS) included an environmental component to increase stocks of more nutritious foods and provided point-of-purchase promotions including signage for healthy choices and interactive nutrition education sessions. Using pre- and postassessments, the authors evaluated the impact of the program on 84 respondents sampled from the intervention and comparison areas. Exposure to intervention materials was modest in the intervention area, and overall healthy food purchasing scores, food knowledge, and self-efficacy did not show significant improvements associated with intervention status. However, based on adjusted multivariate regression results, the BHS program had a positive impact on healthfulness of food preparation methods and showed a trend toward improved intentions to make healthy food choices. Respondents in the intervention areas were significantly more likely to report purchasing promoted foods because of the presence of a BHS shelf label. This is the first food store intervention trial in low-income urban communities to show positive impacts at the consumer level.

Preventing childhood obesity and diabetes: is it time to move out of the school?

Childhood obesity interventions in the USA and Europe have predominantly focused on the school environment for over two decades with mixed or modest success. The focus on school--while intuitive, apparently efficient, and convenient--does not address larger upstream environmental factors, which affect obesity among youth. In this article, we examine potential drawbacks and limitations of previous school-based obesity and diabetes prevention programs. The future of school-based obesity and diabetes interventions and potential strategies for improvement is explored. Increased use and reporting of diversified theoretical frameworks, formative research to inform the interventions, and process evaluations to improve programs are recommended. More importantly, addressing the broader issue of the overall food environment and its impact on children's diet with intensified involvement of key stakeholders, including families, supermarkets, and corner stores is essential. We discuss the development of healthy eating zones around schools as a potential tool in the fight to reduce childhood obesity.

Improved ecdysone receptor-based inducible gene regulation system.

To develop an ecdysone receptor (EcR)-based inducible gene regulation system, several constructs were prepared by fusing DEF domains of Choristoneura fumiferana EcR (CfEcR), C. fumiferana ultraspiracle (CfUSP), Mus musculus retinoid X receptor (MmRXR) to either GAL4 DNA binding domain (DBD) or VP16 activation domain. These constructs were tested in mammalian cells to evaluate their ability to transactivate luciferase gene placed under the control of GAL4 response elements and synthetic TATAA promoter. A two-hybrid format switch, where GAL4 DBD was fused to CfEcR (DEF) and VP16 AD was fused to MmRXR (EF) was found to be the best combination. It had the lowest background levels of reporter gene activity in the absence of a ligand and the highest level of reporter gene activity in the presence of a ligand. Both induction and turn-off responses were fast. A 16-fold induction was observed within 3 h of ligand addition and increased to 8942-fold by 48 h after the addition of ligand. Withdrawal of the ligand resulted in 50% and 80% reduction in reporter gene activity by 12 h and 24 h, respectively.

Highly flexible ligand binding pocket of ecdysone receptor: a single amino acid change leads to discrimination between two groups of nonsteroidal ecdysone agonists.

The insect steroid hormone 20-hydroxyecdysone works through a ligand-activated nuclear receptor, the ecdysone receptor (EcR), which plays critical roles in insect development and reproduction. The EcR has been exploited to develop insecticides to control pests and gene switches for gene regulation. Recently reported crystal structures of the EcR protein show different but partially overlapping binding cavities for ecdysteroid (ECD) and diacylhydrazine (DAH) ligands, providing an explanation for the differential activity of DAH ligands in insects. 1-Aroyl-4-(arylamino)-1,2,3,4-tetrahydroquinoline (THQ) ligands were recently discovered as ecdysone agonists. Mutagenesis of the EcR (from Choristoneura fumiferana, CfEcR) ligand binding domain followed by screening in a reporter assay led to the identification of CfEcR mutants, which responded well to THQ ligands but poorly to both ECD and DAH ligands. These mutants were further improved by introducing a second mutation, A110P, which was previously reported to cause ECD insensitivity. Testing of these V128F/A110P and V128Y/A110P mutants in a C57BL/6 mouse model coactivator interaction assay and in insect cells showed that this mutant EcR is activated by THQ ligands but not by ECD or DAH ligands. The CfEcR and its V128F/A110P mutant were used to demonstrate simultaneous regulation of two reporter genes using THQ and DAH ligands.