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The Cl-/HCO3- exchanger pendrin in the kidney maintains acid-base balance and intravascular volume. Pendrin is upregulated in models associated with high circulating aldosterone concentration, such as dietary NaCl restriction or an aldosterone infusion. However, it has not been established if pendrin is similarly regulated by aldosterone with a high-K+ diet because the effects of accompanying anions have not been considered. Here, we explored how pendrin is modulated by different dietary potassium salts. Wild-type (WT) and aldosterone synthase (AS) knockout (KO) mice were randomized to control, high-KHCO3, or high-KCl diets. Dietary KCl and KHCO3 loading increased aldosterone in WT mice to the same extent but had opposite effects on pendrin abundance. KHCO3 loading increased pendrin protein and transcript abundance. Conversely, high-KCl diet feeding caused pendrin to decrease within 8 h of switching from the high-KHCO3 diet, coincident with an increase in plasma Cl- and a decrease in HCO3-. In contrast, switching the high-KCl diet to the high-KHCO3 diet caused pendrin to increase in WT mice. Experiments in AS KO mice revealed that aldosterone is necessary to optimally upregulate pendrin protein in response to the high-KHCO3 diet but not to increase pendrin mRNA. We conclude that pendrin is differentially regulated by different dietary potassium salts and that its regulation is prioritized by the dietary anion, providing a mechanism to prevent metabolic alkalosis with high-K+ base diets and safeguard against hyperchloremic acidosis with consumption of high-KCl diets. NEW & NOTEWORTHY Regulation of the Cl-/HCO3- exchanger pendrin has been suggested to explain the aldosterone paradox. A high-K+ diet has been proposed to downregulate a pendrin-mediated K+-sparing NaCl reabsorption pathway to maximize urinary K+ excretion. Here, we challenged the hypothesis, revealing that the accompanying anion, not K+, drives pendrin expression. Pendrin is downregulated with a high-KCl diet, preventing acidosis, and upregulated with an alkaline-rich high-K+ diet, preventing metabolic alkalosis. Pendrin regulation is prioritized for acid-base balance. [ABSTRACT FROM AUTHOR]

The present study is a Labovian sociolinguistic analysis of forms used to express the future tense in the spoken French of adolescents residing in Ontario, Canada. Two primary variants are examined: a) the periphrastic future (e.g. elle va partir); and b) the inflected future (e.g. elle partira). The general trend that emerges is that distribution rates of the periphrastic future are markedly higher than previous accounts of the variable and that many speakers are in fact categorical users of the periphrastic form in certain contexts. Note, too, that negation is not a strong predictor for all speakers with respect to the choice of the inflected future, a finding that is in strong contrast to previous analyses of the variable in Laurentian varieties of spoken French in Canada. After presenting the general results, we provide an in-depth analysis of the linguistic and social factors that condition variant use. [ABSTRACT FROM PUBLISHER]

This article features the 10th anniversary of the "Journal of Public Procurement" in 2011. It identifies the journal as a pioneer academic publication in the field of public procurement. It looks back at the decision of Rick Grimm, chief executive officer (CEO) of the National Institute of Governmental Purchasing Inc. (NIGP), to establish the journal. The article expresses gratitude to the board of directors of the NIGP for their continued sponsorship of the journal.