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Objective: The aim of this study is to examine the relationship between the status in selected saturated (SFAs) and monounsaturated (MUFAs) fatty acids and the Stiffness Index (SI) in Inuit women from Nunavik (Northern Quebec, Canada). Design: Cross-sectional descriptive study. Setting: Inuit population from 14 communities who participated to Qanuippitaa? How are we? Nunavik Inuit Health Survey in 2004. Participants: 187 Inuit women aged 35-72 years. Measurements: SI was determined by ultrasonography (Achilles InSight device) at the right calcaneus of participants. SFAs and MUFAs contents of erythrocyte membrane phospholipids were measured after transmethylation by gas chromatography coupled with a flame ionization detector. Several factors known to be associated with bone strength were concomitantly recorded. Multiple linear regression was used to investigate relations between selected SFAs, MUFAs and SI, taking into consideration several potential confounders and covariates. Results: Total SFAs, in particular behenic acid, and cis-vaccenic acid among MUFAs were negatively associated with SI (β = −0.028, SE = 0.011, p = 0.0084; β = −0.060, SE = 0.023, p = 0.0093 and β = −0.087, SE = 0.019, p <0.0001, respectively), whereas total cis-MUFAs and specifically oleic acid were positively associated with SI (β = 0.036, SE = 0.011, p = 0.0008; β = 0.037, SE = 0.011, p = 0.0014, respectively) after adjustment for several covariates. Conclusion: Saturated and monounsaturated fatty acid status is associated with bone strength estimated by calcaneal SI values in Inuit women from Nunavik. [ABSTRACT FROM AUTHOR]

Accumulating data point to K+ channels as relevant players in controlling cell cycle progression and proliferation of human cancer cells, including prostate cancer (PCa) cells. However, the mechanism(s) by which K+ channels control PCa cell proliferation remain illusive. In this study, using the techniques of molecular biology, biochemistry, electrophysiology and calcium imaging, we studied the expression and functionality of intermediate-conductance calcium-activated potassium channels (IKCa1) in human PCa as well as their involvement in cell proliferation. We showed that IKCa1 mRNA and protein were preferentially expressed in human PCa tissues, and inhibition of the IKCa1 potassium channel suppressed PCa cell proliferation. The activation of IKCa1 hyperpolarizes membrane potential and, by promoting the driving force for calcium, induces calcium entry through TRPV6, a cation channel of the TRP (Transient Receptor Potential) family. Thus, the overexpression of the IKCa1 channel is likely to promote carcinogenesis in human prostate tissue.Oncogene (2009) 28, 1792–1806; doi:10.1038/onc.2009.25; published online 9 March 2009 [ABSTRACT FROM AUTHOR]

Background: Inuit women from Northern Québec have been shown to consume inadequate quantities of vitamin A. This study was conducted to evaluate the prevalence of blood vitamin A deficiency in newborns from 3 distinct populations of the province of Québec.Methods: 594 newborns were included in this study (375 Inuit newborns from northern Québec (Nunavik), 107 Caucasian and Native newborns from the Lower Northern Shore of the Saint-Lawrence River (LNS) and 112 newborns from Southern Québec where clinical vitamin A deficiency is uncommon). Mothers were recruited at delivery and vitamin A (retinol) was analyzed from umbilical cord blood samples by reversed-phase high-pressure liquid chromatography.Results: Nunavik and LNS newborns had significantly lower mean vitamin A concentrations in cord blood compared to Southern Québec participants (15.7 microg/dL, 16.8 microg/dL and 20.4 microg/dL respectively). The differences observed were similar when adjusted for sex and birthweight. Results also showed that 8.5% of Nunavik newborns and 12.2% of LNS newborns were below 10.0 microg/dL, a level thought to be indicative of blood vitamin A deficiency in neonates.Conclusion: These data suggest that a carefully planned vitamin A supplementation program during pregnancy in Nunavik and LNS might be indicated to promote healthy infant development. [ABSTRACT FROM AUTHOR]

Objectives: Inuit in Canada experience alarming levels of food insecurity, but nutritional and physiological consequences are poorly documented, especially in school-age children. The objective of this study was to assess the relation of food insecurity to iron deficiency and stature in school-aged Inuit children from Nunavik (Northern Quebec)., Methods: Food insecurity, iron deficiency, and stature were assessed in a cohort of children. Food insecurity was determined by interviewing the children's mothers. Multiple logistic regression was used to evaluate the association of food insecurity to iron deficiency and short stature. We defined short stature as a height in the lowest tertile for age and sex, based on Canadian growth charts. The relation of food insecurity to height (cm) was analyzed with a general linear model. Statistical models controlled for age, sex, normal/overweight/obese status, prenatal lead exposure and postnatal polychlorinated biphenyls exposure., Results: Half of the children (49.7%, n=145) were food insecure, while one third were iron depleted, 12.6% had anaemia, and 8.7% had iron-deficiency anaemia. The multivariate odds ratio of anaemia was 1.82 (95% CI: 0.97, 3.42, p=0.06) for food-insecure children. Prevalence of short stature was 18.7%. Food-insecure children were an average of 2 cm shorter (95% CI: -0.48, -3.17) than food-secure children (p<0.01)., Conclusion: In this population, food-insecure children have greater burdens of nutritional deficiencies and slower linear growth. Considering the high prevalence of food insecurity among Inuit children in Nunavik, nutritional deficiencies and adverse effects on development should be carefully monitored.

Objectives: Aboriginal peoples affected by a nutrition transition and living at high latitudes are among the ethnic groups most at risk of vitamin D deficiency. The objectives of this study were to determine the prevalence of meeting predefined cut-off concentrations of vitamin D and to examine associated factors among James Bay Cree aged ≥ 15 years., Methods: A cross-sectional study was conducted between the months of May and September from 2005 to 2009. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were determined by radioimmunoassay. Anthropometrics were measured and additional information on socio-demographic characteristics, lifestyle and dietary habits was obtained using questionnaires. A logistic regression model predicting vitamin D insufficiency (<50 nmol/L) included known covariates., Results: Data were obtained from 944 Cree (406 men (43%); mean age 37.4 years), with an effective participation rate of 49% among women and 41% among men. Mean serum 25(OH)D concentrations (nmol/L) by gender were 52.9 (95% CI 51.4-54.5) in men and 47.5 (95% CI 46.2-48.9) in women, and by age group were 46.0 (95% CI 44.9-48.9) in those 15-39 years and 59.6 (95% CI 57.9-61.4) in those ≥ 40 years of age. Overall, 5.8%, 42.6%, 40.0%, and 11.7% of the participants had 25(OH)D concentrations <30, 30-49.9, 50-74.9 and ≥ 75 nmol/L, respectively. Female gender, obesity, younger age, spring, low fish and milk intake, and low vigorous physical activity predicted vitamin D insufficiency (all p<0.05)., Conclusion: The vitamin D status in Eastern James Bay Cree is suboptimal with nearly half of the population having insufficient concentrations for optimum bone health.

Objective: To assess if vitamin A concentration in umbilical cord blood is associated with incidence and severity of respiratory infections in preschool Inuit children from Nunavik (Québec, Canada)., Method: The medical charts of 305 children were reviewed from 0 to 5 years of age. The association between vitamin A concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM), lower respiratory tract infections (LRTIs) and hospitalization rates for LRTIs was evaluated using Poisson regression., Results: Compared to children with vitamin A concentration > or =20 microg/dl, adjusted rate ratios (RR) for children below 20 microg/dl ranged between 1.06-1.62 for AOM, 1.12-1.34 for LRTIs, and 1.09-1.43 for hospitalization for LRTIs. Most RRs were statistically significant for AOM and LRTIs, but not for hospitalization for LRTIs., Conclusion: Neonatal vitamin A deficiency appears to be a significant risk factor for AOM and LRTIs in this population.

Objective: Inuit children from around the world are burdened by a high rate of infectious diseases. The objective of this study was to evaluate the incidence rate of infections in Inuit preschool children from Nunavik (Northern Québec)., Methods: The medical chart of 354 children from a previously recruited cohort was reviewed for the first five years of life. All outpatient visits that led to a diagnosis of acute infection and all admissions for acute infections were recorded., Results: Rates of outpatient visits for acute otitis media (AOM) were 2314, 2300, and 732 events/1000 child-years for children 0-11 months, 12-23 months, and 2-4 years, respectively. Rates of outpatient visits for lower respiratory tract infections (LRTI) were 1385, 930, and 328 events/1000 child-years, respectively. Rates of hospitalization for pneumonia were 198, 119, and 31 events/1000 child-years, respectively., Conclusion: Inuit children from Nunavik have high rates of AOM and LRTI. Such rates were higher than that of other non-native North-American populations previously published. Admission for LRTI is up to 10 times more frequent in Nunavik compared to other Canadian populations.

The interactions between humans and the ocean are significant, and necessitate more comprehensive study on an international scale. The world's oceans provide great health benefits to humans ranging from food and nutritional resources, to recreational opportunities and new treatments for human disease. However, recently, human health effects from exposure to substances present in the marine ecosystem such as synthetic organic chemicals (e.g., chlorobiphenyls, chlorinated dioxins and some industrial solvents), polycyclic aromatic hydrocarbons (PAHs), metals (both introduced and anthropogenic), marine toxins, and pathogens have been recorded and are of great concern. This paper reviews our state of knowledge of the interactions between oceans and human health and proposes indicators and a research strategy to investigate and monitor these relationships more closely. Four approaches to gathering information on indicators included here are: biomarkers; cellular pathology; physiological and behavioural responses; and changes in populations. All hold the potential to enhance our understanding of marine environmental quality and far-reaching effects on human health. Monitoring systems that include the rapid assessment of contaminants in the ecosystem and subsequent risk to human populations, with appropriate internationally distributed data bases, need to be developed and validated. Such tools would provide early detection of potential environmental threats, and enhance the ability to prevent human illness.

The iron status and diet of Inuit infants living in northern Quebec who were part of a prospective cohort study was described. The prevalence of anemia (hemoglobin values > 2 SD below the reference mean) was 21.1% (23/109), 47.4% (55/116) and 37.7% (46/122) at 2, 6 and 12 months, respectively. The corresponding prevalence of microcytic anemia was 0.0%, 4.3% and 21.3%. At 2, 6 and 12 months, iron-deficiency anemia (serum ferritin < 10 micrograms/L coupled with anemia) was present in 1.3% (1/79), 24.4% (21/86) and 26.3% (25/95) of infants, respectively. Compared with breastfeeding, the odds ratio for iron deficiency (serum ferritin < 10 micrograms/L) for bottle-feeding with cows' milk or low iron formula was 3.02 (95% CI 1.25-7.27) at 6 months and 3.05 (95% CI 1.28-7.28) at 12 months. This study shows iron-deficiency anemia to be a problem in Inuit infants as young as 6 months old. Breastfed infants were better protected against iron deficiency than infants fed cow's milk or low-iron formula.

This article documents the exposure to environmental contaminants within sub-groups of the Canadian population who are considered to be at risk as a result of the food they eat. We measured the concentrations of polychlorinated biphenyls (PCBs) and mercury in the blood drawn from the umbilical cords of newborns in various Aboriginal communities, in a coastal community and in the general population. Average concentrations of Aroclor 1260 ranged between 0.3 and 2.0 micrograms/L and were clearly highest among the Inuit of Nunavik and Baffin Island and among the Montagnais of Quebec. In these groups, we found contaminant levels in the blood of newborns that exceed the threshold beyond which cognitive impairments are expected to result. Average concentrations of mercury ranged between 1.0 and 14.2 micrograms/L; the Inuit of Nunavik and the NWT exhibited the highest exposure levels. A portion of the Nunavik and NWT Inuit had concentrations beyond the critical threshold for the appearance of neurological consequences. The variations in exposure levels resulted from the different nutritional practices of these Canadian sub-groups.