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In rat distal colon, aldosterone has little effect on Na+ channel (ENaC) α-subunit levels but increases the expression of the β- and γ-subunits and stimulates electrogenic Na+ transport. By contrast, the molecular basis of aldosterone's inability to stimulate electrogenic Na+ transport in the proximal colon is unclear. We therefore compared the effects of hyperaldosteronism secondary to 10 days dietary Na+ depletion on ENaC subunit expression in rat proximal and distal colon. Northern analyses revealed appreciable and similar levels of α-subunit mRNA throughout the colon in control and Na+-depleted animals. By contrast, Na+ depletion substantially enhanced β-subunit mRNA expression in the distal colon, but had no effect on the low expression levels of β-subunit mRNA in the proximal colon. Expression of the γ-subunit, evaluated by PCR, was also restricted to the distal colon of Na+-depleted animals. Western analyses demonstrated similar levels of α-subunit protein in the proximal and distal colon of both groups of animals, whereas β-subunit and γ-subunit proteins were detected solely or predominantly in the distal colon of the Na+-depleted animals. Immunocytochemistry confirmed that significant levels of all three subunit proteins only occurred in the apical membrane of surface cells in the distal colon of Na+-depleted animals. Our findings are consistent with previous studies demonstrating that aldosterone stimulates electrogenic Na+ transport in rat distal colon by increasing the expression of β- and γ-subunit mRNA and protein, and thus the amount of functional heteromeric ENaC protein in the apical domain. They also show that aldosterone is incapable of stimulating electrogenic Na+ transport in rat proximal colon (despite the presence of α-subunit mRNA and protein) because of its inability to enhance β- and γ-subunit expression in this segment. [ABSTRACT FROM AUTHOR]

Polistes dominulus (Christ), an old world paper wasp, was introduced accidentally into the eastern coast of the United States in the late 1970s and has been rapidly spreading westward, displacing the native P. fuscatus (F.). The biology of naturally nesting P. fuscatus and P. dominulus was compared at a field site in Rochester, Michigan. The basic methodology consisted of simultaneously videotaping spatially proximate, matched single-foundress colonies of P. fuscatus and P. dominulus (13 matched sets, 176.8 h of videography). In addition, extensive surveys and censuses were taken of colonies to record colony productivity, dates of nest initiation and first worker emergence, usurpation and parasitism.¶There was no evidence that P. dominulus is negatively impacting P. fuscatus through direct, agonistic encounters. However, P. dominulus is 4-5 times more productive than P. fuscatus, suggesting that P. dominulus is replacing P. fuscatus via exploitative competition. P. dominulus appears to have a number of advantages over P. fuscatus, including earlier production of workers, higher per capita foraging rates by queens and workers, higher queen survivorship, and lack of conspecific pressures. Nest site and/or prey availability may be limiting factors in the competition between the two species. [ABSTRACT FROM AUTHOR]

Chronic idiopathic intestinal pseudo-obstruction (CIIP) is characterised by a failure of intestinal propulsion in the absence of mechanical obstruction. Patients with CIIP may have characteristic histological, radiographic, or manometric findings. CIIP may be primary, or secondary. CIIP is difficult to classify clinically and diagnosis may depend upon several investigations. Patients with normal histology but abnormal manometric or radiographic findings often present with pain first, are more likely to need home parenteral nutrition and may have a high mortality.

Patients with chronic idiopathic intestinal pseudo-obstruction often suffer severe pain, vomiting, constipation and abdominal distension. There are currently few data published on the quality of life of this patient population. This study concludes that about a fifth of patients have clinically significant anxiety and a sixth depression. Physical role and general health scored much lower than normal whereas mental health scores were much closer to the norm.