Knock out of neuronal nitric oxide synthase exacerbates intestinal ischemia/reperfusion injury in mice

Recent investigation of the intestine following ischemia and reperfusion (I/R) has revealed that nitric oxide synthase (NOS) neurons are more strongly affected than other neuron types. This implies that NO originating from NOS neurons contributes to neuronal damage. However, there is also evidence of the neuroprotective effects of NO. In this study, we compared the effects of I/R on the intestines of neuronal NOS knockout (nNOS(-/-)) mice and wild-type mice. I/R caused histological damage to the mucosa and muscle and infiltration of neutrophils into the external muscle layers. Damage to the mucosa and muscle was more severe and greater infiltration by neutrophils occurred in the first 24 h in nNOS(-/-) mice. Immunohistochemistry for the contractile protein, alpha-smooth muscle actin, was used to evaluate muscle damage. Smooth muscle actin occurred in the majority of smooth muscle cells in the external musculature of normal mice but was absent from most cells and was reduced in the cytoplasm of other cells following I/R. The loss was greater in nNOS(-/-) mice. Basal contractile activity of the longitudinal muscle and contractile responses to nerve stimulation or a muscarinic agonist were reduced in regions subjected to I/R and the effects were greater in nNOS(-/-) mice. Reductions in responsiveness also occurred in regions of operated mice not subjected to I/R. This is attributed to post-operative ileus that is not significantly affected by knockout of nNOS. The results indicate that deleterious effects are greater in regions subjected to I/R in mice lacking nNOS compared with normal mice, implying that NO produced by nNOS has protective effects that outweigh any damaging effect of this free radical produced by enteric neurons.

Nutritional transition of school children from low income families of a northeastern urban area, Brazil

Background: Evaluating child growth is, in practice, performed by measuring the development of a child's weight, height, and body composition in comparison to averages observed among a reference population. Objective: To describe the nutritional status of children of low income families who live in urban region in northeastern Brazil. Methods: This study is a population case series with a transversal and observational design. The study population consisted of 257 children, aged 5 to 10 years, who were enrolled in a public school to children of low income families. We used the cutoff point for short stature of -2 Z scores for age, and underweight, overweight, and obese were classified as the 5th, 85th, and 95th percentiles, respectively, of the body mass index (BMI) for age, with both classifications in accordance with the Center for Disease Control and Prevention (CDC 2000). Comparisons by gender were performed for the measures of the central tendency and the frequency of diagnoses, in addition to the tendency of the evolution of BMI by age. Results: The prevalence of short stature was 3.5% (95% CI: 1.9-6.5). In the evaluation of BMI for age, the prevalences found for underweight, overweight, and obese were 5.8% (95% CI: 3.6-9.4), 4.7% (95% CI: 2.7-8.0), and 2.3% (95% CI: 1.1-5.0), respectively. We found a significant trend in the reduction of BMI with the increase in age. Conclusions: According to CDC references, the prevalences of underweight and short stature were higher than expected and for the overweight and obesity were lower than expected, indicating that the nutritional transition had still not reached, as commonly is described, these low income children from the urban outskirts of the Northeast region.

Can activity be understood out of subjectivity?

The PSR echo a crisis of the relation of the organization with the subjectivity, which is at the same time a crisis of the relation of the organization with the reality that subjectivity is confronting through activity. Thus, they also raise, with ergonomics, the question to know which place it grants itself to subjectivity in the relation health-effectiveness.