Sex and pubertal variation in reward-related behavior and neural activation in early adolescents.

This study aimed to characterize the role of sex and pubertal markers in reward motivation behavior and neural processing in early adolescence. We used baseline and two-year follow-up data from the Adolescent Brain and Cognitive DevelopmentSM study (15844 observations; 52% from boys; age 9-13). Pubertal development was measured with parent-reported Pubertal Development Scale, and DHEA, testosterone, and estradiol levels. Reward motivation behavior and neural processing at anticipation and feedback stages were assessed with the Monetary Incentive Delay task. Boys had higher reward motivation than girls, demonstrating greater accuracy difference between reward and neutral trials and higher task earnings. Girls had lower neural activation during reward feedback than boys in the nucleus accumbens, caudate, rostral anterior cingulate, medial orbitofrontal cortex, superior frontal gyrus and posterior cingulate. Pubertal stage and testosterone levels were positively associated with reward motivation behavior, although these associations changed when controlling for age. There were no significant associations between pubertal development and neural activation during reward anticipation and feedback. Sex differences in reward-related processing exist in early adolescence, signaling the need to understand their impact on typical and atypical functioning as it unfolds into adulthood.

Therapeutic administration of Budesonide ameliorates allergen-induced airway remodelling.

BACKGROUND: Airway inflammation and remodelling are important pathophysiologic features of chronic asthma. Although current steroid use demonstrates anti-inflammatory activity, there are limited effects on the structural changes in the lung tissue. OBJECTIVE: We have used a mouse model of prolonged allergen challenge that exhibits many of the salient features of airway remodelling in order to investigate the anti-remodelling effects of Budesonide. METHODS: Treatment was administered therapeutically, with dosing starting after the onset of established eosinophilic airway inflammation and hyper-reactivity. RESULTS: Budesonide administration reduced airway hyper-reactivity and leukocyte infiltration in association with a decrease in production of the Th2 mediators, IL-4, IL-13 and eotaxin-1. A reduction in peribronchiolar collagen deposition and mucus production was observed. Moreover, our data show for the first time that, Budesonide treatment regulated active transforming growth factor (TGF)-beta signalling with a reduction in the expression of pSmad 2 and the concomitant up-regulation of Smad 7 in lung tissue sections. CONCLUSIONS: Therefore, we have determined that administration of Budesonide modulates the progression of airway remodelling following prolonged allergen challenge via regulation of inflammation and active TGF-beta signalling.

Prolonged allergen challenge in mice leads to persistent airway remodelling.

BACKGROUND: Inflammatory infiltrates, airway hyper-responsiveness, goblet cell hyperplasia and subepithelial thickening are characteristic of chronic asthma. Current animal models of allergen-induced airway inflammation generally concentrate on the acute inflammation following allergen exposure and fail to mimic all of these features. OBJECTIVE: The aim of this study was to use a murine model of prolonged allergen-induced airway inflammation in order to characterize the cells and molecules involved in the ensuing airway remodelling. Moreover, we investigated whether remodelling persists in the absence of continued allergen challenge. METHODS: Acute pulmonary eosinophilia and airways hyper-reactivity were induced after six serial allergen challenges in sensitized mice (acute phase). Mice were subsequently challenged three times a week with ovalbumin (OVA) (chronic phase) up to day 55. To investigate the persistence of pathology, one group of mice were left for another 4 weeks without further allergen challenge (day 80). RESULTS: The extended OVA challenge protocol caused significant airway remodelling, which was absent in the acute phase. Specifically, remodelling was characterized by deposition of collagen as well as airway smooth muscle and goblet cell hyperplasia. Importantly, these airway changes, together with tissue eosinophilia were sustained in the absence of further allergen challenge. Examination of cytokines revealed a dramatic up-regulation of IL-4 and tumour growth factor-beta1 during the chronic phase. Interestingly, while IL-4 levels were significantly increased during the chronic phase, levels of IL-13 fell. Levels of the Th1-associated cytokine IFN-gamma also increased during the chronic phase. CONCLUSION: In conclusion, we have demonstrated that prolonged allergen challenge results in persistent airway wall remodelling.

Food and nutrition policy issues in remote aboriginal communities: lessons from Arnhem Land.

There is a high incidence of nutrition-related diseases amongst Aborigines living in remote areas. An outline of the corporate food and nutrition policy of the Arnhemland Progress Association is given to demonstrate the potential for positive strategies in remote area stores. The Association is a retailer owned by Aboriginal groups and operates 11 remote community stores. Factors such as price, Aboriginal buying habits, seasonality, consumer demand and most importantly remote area stock management affect the supply of and demand for food items. Further, government policy on sales tax and private sector capital city pricing policies influence retailing in remote areas. The experience of the Arnhemland Progress Association illustrates the extent to which factors affecting supply of and demand for food lie outside the health sector and points to the need for an intersectoral policy on food and nutrition.