Seasonality of the dietary dimension of household food security in urban Burkina Faso

Food insecurity is affecting an increasing number of urban poor in the developing world. Yet seasonal characteristics of food intakes have rarely been studied in West African cities. The objective of the present study was to assess the seasonality of the dietary dimension of household food security in Ouagadougou (Burkina Faso). In 2007, two sets of data were collected during the lean and post-harvest seasons, respectively, on a representative sample of 1056 households. At each season, two non-consecutive 24 h recalls were performed at the household level. Food prices were also recorded. Household food security was assessed by the household's mean adequacy ratio (MAR) for energy and eleven micronutrients. Changes in the MAR according to the season were analysed by mixed multivariate linear regression. Results showed that intakes of energy and of ten micronutrients were significantly lower during the lean season than during the post-harvest season, leading to a lower MAR in the lean season (49·61 v. 53·57, P < 0·0001). This was related to less frequent consumption and consumption of smaller amounts of vegetables and of foods prepared at home. Food security relied heavily on food expenses (P < 0·0001) and on the price of meat/fish (P = 0·026). Households with economically dependent adults (P = 0·021) and larger households (P < 0·0001) were the most vulnerable, whereas education (P = 0·030), social network (P = 0·054) and urban origin other than Ouagadougou (P = 0·040) played a positive role in food security. To achieve food security in Ouagadougou, access to micronutrient-dense foods needs to be ensured in all seasons.     

The 2008 food price crisis negatively affected household food security and dietary diversity in urban burkina faso

Although the 2008 food price crisis presumably plunged millions of households into poverty and food insecurity, the real impact of the crisis has rarely been documented using field data. Our objective was to assess the consequences of this crisis for household food insecurity and dietary diversity in urban Burkina Faso. Two cross-sectional surveys were conducted among randomly selected households in Ouagadougou in July 2007 (n = 3017) and July 2008 (n = 3002). At each round, food insecurity assessed by the Household Food Insecurity Access Scale (HFIAS), the Dietary Diversity Score of an index-member of the household (IDDS = number of food groups consumed in the last 24 h), and food expenditure were collected. Food prices of the 17 most frequently consumed food items were recorded throughout the study area. Food prices at local markets increased considerably between 2007 and 2008, especially those of fish (113%), cereals (53%), and vegetable oil (44%), increasing the household monthly food expenditure by 18%. Thirty-three percent of households were food secure in 2007 and 22% in 2008 (P = 0.02). Individuals consumed fewer fruits and vegetables, dairy products, and meat/poultry in 2008 than in 2007 (mean IDDS = 5.7 ± 1.7 food groups in 2007 vs. 5.2 ± 1.5 in 2008; P < 0.0001). Differences in IDDS and HFIAS between the 2 y were even more marked after adjustment for confounding factors and food expenditure. Food security and dietary diversity significantly decreased between 2007 and 2008, whereas food prices increased. Households increased their food expenditure, but this was not sufficient to compensate the effects of the crisis.     

In vivo Overhauser‐enhanced MRI of proteolytic activity

There is an increasing interest in developing novel imaging strategies for sensing proteolytic activities in intact organisms in vivo. Overhauser‐enhanced MRI (OMRI) offers the possibility to reveal the proteolysis of nitroxide‐labeled macromolecules thanks to a sharp decrease of the rotational correlation time of the nitroxide moiety upon cleavage. In this paper, this concept is illustrated in vivo at 0.2 T using nitroxide‐labeled elastin orally administered in mice. In vitro, this elastin derivative was OMRI‐visible and gave rise to high Overhauser enhancements (19‐fold at 18 mm nitroxide) upon proteolysis by pancreatic porcine elastase. In vivo three‐dimensional OMRI detection of proteolysis was carried out. A keyhole fully balanced steady‐state free precession sequence was used, which allowed 3D OMRI acquisition within 20 s at 0.125 mm³ resolution. About 30 min after mouse gavage, proteolysis was detected in the duodenum, where Overhauser enhancements were 7.2 ± 2.4 (n = 7) and was not observed in the stomach. Conversely, orally administered free nitroxides or pre‐digested nitroxide‐labeled elastin were detected in the mouse's stomach by OMRI. Combined with specific molecular probes, this Overhauser‐enhanced MRI technique can be used to evaluate unregulated proteolytic activities in various models of experimental diseases and for drug testing. Copyright © 2014 John Wiley & Sons, Ltd.     

Sex hormones and cardiomyopathic phenotype induced by cardiac beta 2-adrenergic receptor overexpression

Sex differences in cardiomyopathic phenotype and the role of gonadal status were studied in mice with cardiac overexpression of beta(2)-adrenergic receptors (ARs) over 6-15 months (mo) of age. Survival to 15 mo was 96% in wild-type mice but was poorer in transgenic (TG) mice and lower for males than females (13% vs. 56%, P < 0.001). Echocardiography demonstrated progressive left ventricular (LV) dilatation and reduction in LV fractional shortening in male but much less marked changes in female TG mice. Incidences of atrial thrombosis, pleural effusion and lung congestion were higher and myocyte size and fibrosis in the LV were greater in TG males than females. Deprivation of testicular hormones by castration during 3-15 mo of age improved survival and significantly ameliorated LV dysfunction, remodeling, and hypertrophy compared with intact TG males. No significant effect, except for a trend of a better survival, was detected by ovariectomy in TG females. In conclusion, cardiac beta(2)-AR overexpression at a high level leads to cardiomyopathy and heart failure with aging. Female mice had less cardiac remodeling, dysfunction, and pathology and a marked survival advantage over male mice, and this was independent of prevailing levels of ovarian hormones. TG males showed benefit from orchiectomy, suggesting a contribution by testicular hormones to the progression of the cardiomyopathic phenotype.     

TACI, unlike BAFF-R, is solely activated by oligomeric BAFF and APRIL to support survival of activated B cells and plasmablasts

The cytokine BAFF binds to the receptors TACI, BCMA, and BAFF-R on B cells, whereas APRIL binds to TACI and BCMA only. The signaling properties of soluble trimeric BAFF (BAFF 3-mer) were compared with those of higher-order BAFF oligomers. All forms of BAFF bound BAFF-R and TACI, and elicited BAFF-R-dependent signals in primary B cells. In contrast, signaling through TACI in mature B cells or plasmablasts was only achieved by higher-order BAFF and APRIL oligomers, all of which were also po-tent activators of a multimerization-dependent reporter signaling pathway. These results indicate that, although BAFF-R and TACI can provide B cells with similar signals, only BAFF-R, but not TACI, can respond to soluble BAFF 3-mer, which is the main form of BAFF found in circulation. BAFF 60-mer, an efficient TACI agonist, was also detected in plasma of BAFF transgenic and nontransgenic mice and was more than 100-fold more active than BAFF 3-mer for the activation of multimerization-dependent signals. TACI supported survival of activated B cells and plasmablasts in vitro, providing a rational basis to explain the immunoglobulin deficiency reported in TACI-deficient persons.