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This study clarifies within-family and between-family links between marital functioning and child wellbeing. Expanding on existing prospective research, this study tests whether changes in parents’ marital functioning are associated with corresponding changes in their children’s wellbeing, independent from associations that exist when comparing different families. Participants (N = 1033) were members of married, opposite-sex couples with children who participated in five waves of a larger study of marriage in the U.S. Army. Spouses’ constructive communication, verbal conflict, and marital satisfaction each showed between-family associations with parent-reported child internalizing and externalizing problems. In contrast, within-family associations were significant only for parents’ communication behaviors. That is, parents who reported lower levels of marital satisfaction also reported lower child wellbeing, whereas change in parents’ communication was associated with change in child wellbeing over time. Isolating within-family effects is important for understanding marital and child functioning and for identifying potential targets for effective intervention.

To examine the effect of the Affordable Care Act (ACA) on changes in premiums for subscribers of nongrandfathered, nongroup insurance plans that were "cancelled."Retrospective multivariate analyses.Changes in annual premiums post ACA were evaluated across subgroups of subscriber and health plan characteristics. Data was derived from databases containing information on premiums, plan benefit, and demographics for subscribers aged 18 to 64 years within Kaiser Permanente of the Mid-Atlantic States. A linear regression model was used to examine the independent association between subscriber and health plan characteristics on the relative change in premiums.In 2013, 4169 nongroup subscribers were enrolled in plans that were cancelled as a result of the ACA. The median pre-ACA premium was $3240 (range = $780-$39,492), which increased by a median of 21.3% (range = -77.4% to 193.6%), or $685 (range = -$27,464 to $8676), post ACA in 2014. Premiums increased more for high-deductible plans (median = 63.7%) than standard-deductible plans (median = 8.4%). Due to shifts in the age curve, premiums decreased for more than half of women aged 18 to 44 years, but increased by 35.2% for women aged 55 to 64 years. Premiums fell by 15.5% for subscribers who did not pass standard medical underwriting due to preexisting conditions.Changes in premiums in the nongroup market post ACA, varied substantially across subgroups, primarily due to differences in the amount of coverage, changes in rating criteria, shifts in the age curve, and anticipated differences in risk selection and composition of the risk pool. Given the extent of this variation, it would be incorrect to conclude the ACA as being uniformly beneficial or detrimental to subscribers of these cancelled plans.

Host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. Many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts(1). Host adaptation can potentially progress to host restriction where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. Host-adapted and host-restricted bacterial clades evolve from within a broader host-promiscuous species and sometimes target different niches within their specialist hosts, such as adapting from a mucosal to a systemic lifestyle. Genome degradation, marked by gene inactivation and deletion, is a key feature of host adaptation, although the triggers initiating genome degradation are not well understood. Here, we show that a chronic systemic non-typhoidal Salmonella infection in an immunocompromised human patient resulted in genome degradation targeting genes that are expendable for a systemic lifestyle. We present a genome-based investigation of a recurrent blood-borne Salmonella enterica serotype Enteritidis (S. Enteritidis) infection covering 15 years in an interleukin (IL)-12 β-1 receptor-deficient individual that developed into an asymptomatic chronic infection. The infecting S. Enteritidis harbored a mutation in the mismatch repair gene mutS that accelerated the genomic mutation rate. Phylogenetic analysis and phenotyping of multiple patient isolates provides evidence for a remarkable level of within-host evolution that parallels genome changes present in successful host-restricted bacterial pathogens but never before observed on this timescale. Our analysis identifies common pathways of host adaptation and demonstrates the role that immunocompromised individuals can play in this process.

Court adjudication is considered as a public good and therefore as being non-rivalrous and non-excludable. These characteristic shapes the behavior of natural and legal persons and the governments' stance towards adjudication. In case public goods' characteristics are inherent to adjudication, i.e. attributes which adjudication has without outside interferences, any attempt to treat adjudication as a private good may create legal uncertainty and political instability. In practice, non-rivalrous and non-excludable are not inherent characteristics of adjudication, but consequences of governments' stance towards “public goods”. Therefore, whether or not adjudication is a public good dependents on the government's stance. This paper argues that the competition of civil justice systems can influence governments' stance and therefore change the nature of adjudication.

The recent proposal that Dra/Slc26a3 mediates electrogenic 2Cl−/1HCO3− exchange suggests a required revision of classical concepts of electroneutral Cl− transport across epithelia such as the intestine. We investigated 1) the effect of endogenous Dra Cl−/HCO3− activity on apical membrane potential ( Va) of the cecal surface epithelium using wild-type (WT) and knockout (KO) mice; and 2) the electrical properties of Cl−/(OH−)HCO3− exchange by mouse and human orthologs of Dra expressed in Xenopus oocytes. Ex vivo 36Cl− fluxes and microfluorometry revealed that cecal Cl−/HCO3− exchange was abolished in the Dra KO without concordant changes in short-circuit current. In microelectrode studies, baseline Va of Dra KO surface epithelium was slightly hyperpolarized relative to WT but depolarized to the same extent as WT during luminal Cl− substitution. Subsequent studies indicated that Cl−-dependent Va depolarization requires the anion channel Cftr. Oocyte studies demonstrated that Dra-mediated exchange of intracellular Cl− for extracellular HCO3− is accompanied by slow hyperpolarization and a modest outward current, but that the steady-state current-voltage relationship is unaffected by Cl− removal or pharmacological blockade. Further, Dra-dependent 36Cl− efflux was voltage-insensitive in oocytes coexpressing the cation channels ENaC or ROMK. We conclude that 1) endogenous Dra and recombinant human/mouse Dra orthologs do not exhibit electrogenic 2Cl−/1HCO3− exchange; and 2) acute induction of Dra Cl−/HCO3− exchange is associated with secondary membrane potential changes representing homeostatic responses. Thus, participation of Dra in coupled NaCl absorption and in uncoupled HCO3− secretion remains compatible with electroneutrality of these processes, and with the utility of electroneutral transport models for predicting epithelial responses in health and disease.

Aims The apical membrane anion exchanger putative anion transporter-1 (Pat-1) is expressed at significant levels in the lower villus epithelium of murine duodenum. However, previous studies of Cl(−)/HCO₃(−) exchange in the lower villus have failed to demonstrate Pat-1 function. Those studies routinely included luminal glucose which induces Na(+) -coupled glucose transport and acidifies the villus epithelium. Since Pat-1 has been proposed to be an electrogenic 1Cl(−)/2HCO₃(−) exchanger, membrane depolarization or cell acidification during glucose transport may obscure Pat-1 activity. Therefore, we investigated the effects of luminal glucose on Cl(−)(IN)/HCO₃(−) (OUT) exchange activity in the lower villus epithelium. Methods Cl(−)(IN) /HCO (−) (OUT) exchange of villus epithelium in duodenal mucosa from Pat-1 knockout (KO), Slc26a3 [down-regulated in adenoma (Dra)] KO, cystic fibrosis transmembrane conductance regulator (Cftr) KO and wild-type (WT) littermate mice was measured using the pH-sensitive dye 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein. Short-circuit current (I(sc) ) was measured in Ussing chambers. Results During glucose absorption, Cl(−)(IN)/HCO₃(−) (OUT) exchange in the lower villus epithelium was abolished in the Dra KO and unaffected in the Pat-1 KO relative to WT. However, during electroneutral mannose absorption or electrogenic α-D-methyl glucoside absorption, Cl(−)(IN) /HCO₃(−) (OUT) exchange was reduced in both Pat-1 KO and Dra KO villi. Exposure to high [K(+)] abolished Cl(−)(IN) /HCO₃(−) (OUT) exchange in the Dra KO but not the Dra/Cftr double KO epithelium, suggesting that Pat-1 activity is little affected by membrane depolarization except in the presence of Cftr. Conclusions The metabolic and electrogenic activity of glucose transport obscures Cl(−)(IN) /HCO₃(−) (OUT) exchange activity of Pat-1 in the lower villus. The inhibitory effects of membrane depolarization on Pat-1 Cl(−)(IN) /HCO₃(−) (OUT) exchange may require concurrent membrane association with Cftr.

The majority of dietary amino acids are absorbed via the H+-di-/tripeptide transporter Pept1 of the small intestine. Proton influx via Pept1 requires maintenance of intracellular pH (pHi) to sustain the driving force for peptide absorption. The apical membrane Na+/H+exchanger Nhe3 plays a major role in minimizing epithelial acidification during H+-di-/tripeptide absorption. However, the contributions of HCO3−-dependent transporters to this process have not been elucidated. In this study, we investigate the role of putative anion transporter-1 (Pat-1), an apical membrane anion exchanger, in epithelial pHiregulation during H+-peptide absorption. Using wild-type (WT) and Pat-1(−) mice, Ussing chambers were employed to measure the short-circuit current ( Isc) associated with Pept1-mediated glycyl-sarcosine (Gly-Sar) absorption. Microfluorometry was used to measure pHiand Cl−/HCO3−exchange in the upper villous epithelium. In CO2/HCO3−-buffered Ringers, WT small intestine showed significant Gly-Sar-induced Iscand efficient pHiregulation during pharmacological inhibition of Nhe3 activity. In contrast, epithelial acidification and reduced Iscresponse to Gly-Sar exposure occurred during pharmacological inhibition of Cl−/HCO3−exchange and in the Pat-1(−) intestine. Pat-1 interacts with carbonic anhydrase II (CAII), and studies using CAII(−) intestine or the pharmacological inhibitor methazolamide on WT intestine resulted in increased epithelial acidification during Gly-Sar exposure. Increased epithelial acidification during Gly-Sar exposure also occurred in WT intestine during inhibition of luminal extracellular CA activity. Measurement of Cl−/HCO3−exchange in the presence of Gly-Sar revealed an increased rate of Cl−OUT/HCO3−INexchange that was both Pat-1 dependent and CA dependent. In conclusion, Pat-1 Cl−/HCO3−exchange contributes to pHiregulation in the villous epithelium during H+-dipeptide absorption, possibly by providing a HCO3−import pathway.

Cystic fibrosis is caused by mutations in CFTR, the cystic fibrosis transmembrane conductance regulator gene. Disruption of CFTR-mediated anion conductance results in defective fluid and electrolyte movement in the epithelial cells of organs such as the pancreas, airways and sweat glands, but the function of CFTR in salivary glands is unclear. Salivary gland acinar cells produce an isotonic, plasma-like fluid, which is subsequently modified by the ducts to produce a hypotonic, NaCl-depleted final saliva. In the present study we investigated whether submandibular salivary glands (SMGs) in ΔF508 mice (CftrΔF/ΔF) display ion transport defects characteristic of cystic fibrosis in other tissues. Immunolocalization and whole-cell recordings demonstrated that Cftr and the epithelial Na+ (ENaC) channels are co-expressed in the apical membrane of submandibular duct cells, consistent with the significantly higher saliva [NaCl] observed in vivo in CftrΔF/ΔF mice. In contrast, Cftr and ENaC channels were not detected in acinar cells, nor was saliva production affected in CftrΔF/ΔF mice, implying that Cftr contributes little to the fluid secretion process in the mouse SMG. To identify the source of the NaCl absorption defect in CftrΔF/ΔF mice, saliva was collected from ex vivo perfused SMGs. CftrΔF/ΔF glands secreted saliva with significantly increased [NaCl]. Moreover, pharmacological inhibition of either Cftr or ENaC in the ex vivo SMGs mimicked the CftrΔF/ΔF phenotype. In summary, our results demonstrate that NaCl absorption requires and is likely to be mediated by functionally dependent Cftr and ENaC channels localized to the apical membranes of mouse salivary gland duct cells.

The Ussing chamber provides a physiological system to measure the transport of ions, nutrients, and drugs across various epithelial tissues. One of the most studied epithelia is the intestine, which has provided several landmark discoveries regarding the mechanisms of ion transport processes. Adaptation of this method to mouse intestine adds the dimension of investigating genetic loss or gain of function as a means to identify proteins or processes affecting transepithelial transport. In this review, the principles underlying the use of Ussing chambers are outlined including limitations and advantages of the technique. With an emphasis on mouse intestinal preparations, the review covers chamber design, commercial equipment sources, tissue preparation, step-by-step instruction for operation, troubleshooting, and examples of interpretation difficulties. Specialized uses of the Ussing chamber such as the pH stat technique to measure transepithelial bicarbonate secretion and isotopic flux methods to measure net secretion or absorption of substrates are discussed in detail, and examples are given for the adaptation of Ussing chamber principles to other measurement systems. The purpose of the review is to provide a practical guide for investigators who are new to the Ussing chamber method.

Ischemic injury induces breakdown of the intestinal barrier. Recent studies in porcine postischemic tissues indicate that inhibition of NHE2 results in enhanced recovery of barrier function in vitro via a process involving interepithelial tight junctions. To further study this process, recovery of barrier function was assessed in wild-type (NHE2+/+) and NHE2−/− mice in vivo and wild-type mice in vitro. Mice were subjected to complete mesenteric ischemia in vivo, after which barrier function was measured by blood-to-lumen mannitol clearance over a 3-h recovery period or measurement of transepithelial electrical resistance (TER) in Ussing chambers immediately following ischemia. Tissues were assessed for expression of select junctional proteins. Compared with NHE2+/+ mice, NHE2−/− mice had greater intestinal permeability during the postischemic recovery process. In contrast to prior porcine studies, pharmacological inhibition of NHE2 in postischemic tissues from wild-type mice also resulted in significant reductions in TER. Mucosa from NHE2−/− mice displayed a shift of occludin and claudin-1 expression to the Triton-X-soluble membrane fractions and showed disruption of occludin and claudin-1 localization patterns following injury. This was qualitatively and quantitatively recovered in NHE2+/+ mice compared with NHE2−/− mice by the end of the 3-h recovery period. Serine phosphorylation of occludin and claudin-1 was downregulated in NHE2−/− postischemia compared with wild-type mice. These data indicate an important role for NHE2 in recovery of barrier function in mice via a mechanism involving tight junctions.

Basal HCO3− secretion across the duodenum has been shown in several species to principally involve the activity of apical membrane Cl−/HCO3− exchanger(s). To investigate the identity of relevant anion exchanger(s), experiments were performed using wild-type (WT) mice and mice with gene-targeted deletion of the following Cl−/HCO3− exchangers localized to the apical membrane of murine duodenal villi: Slc26a3 [down-regulated in adenoma (DRA)], Slc26a6 [putative anion transporter 1 (PAT-1)], and Slc4a9 [anion exchanger 4 (AE4)]. RT-PCR of the isolated villous epithelium demonstrated PAT-1, DRA, and AE4 mRNA expression. Using the pH-sensitive dye BCECF, anion exchange rates were measured across the apical membrane of epithelial cells in the upper villus of the intact duodenal mucosa. Under basal conditions, Cl−/HCO3− exchange activity was reduced by 65–80% in the PAT-1(−) duodenum, 30–40% in the DRA(−) duodenum, and 42−/HCO3− exchange was eliminated in the PAT-1(−) duodenum but was not affected in the DRA(−) and AE4(−) duodenum relative to the WT duodenum. Intracellular pH (pHi) was reduced in the PAT-1(−) villous epithelium but increased to WT levels in the absence of CO2/HCO3− or during methazolamide treatment. Further experiments under physiological conditions indicated active pHi compensation in the PAT-1(−) villous epithelium by combined activities of Na+/H+ exchanger 1 and Cl−-dependent transport processes at the basolateral membrane. We conclude that 1) PAT-1 is the major contributor to basal Cl−/HCO3− and SO42−/HCO3− exchange across the apical membrane and 2) PAT-1 plays a role in pHi regulation in the upper villous epithelium of the murine duodenum.