The urea transporter family (SLC14): physiological, pathological and structural aspects

Urea transporters (UTs) belonging to the solute carrier 14 (SLC14) family comprise two genes with a total of eight isoforms in mammals, UT-A1 to -A6 encoded by SLC14A2 and UT-B1 to -B2 encoded by SLC14A1. Recent efforts have been directed toward understanding the molecular and cellular mechanisms involved in the regulation of UTs using transgenic mouse models and heterologous expression systems, leading to important new insights. Urea uptake by UT-A1 and UT-A3 in the kidney inner medullary collecting duct and by UT-B1 in the descending vasa recta for the countercurrent exchange system are chiefly responsible for medullary urea accumulation in the urinary concentration process. Vasopressin, an antidiuretic hormone, regulates UT-A isoforms via the phosphorylation and trafficking of the glycosylated transporters to the plasma membrane that occurs to maintain equilibrium with the exocytosis and ubiquitin-proteasome degradation pathways. UT-B isoforms are also important in several cellular functions, including urea nitrogen salvaging in the colon, nitric oxide pathway modulation in the hippocampus, and the normal cardiac conduction system. In addition, genomic linkage studies have revealed potential additional roles for SLC14A1 and SLC14A2 in hypertension and bladder carcinogenesis. The precise role of UT-A2 and presence of the urea recycling pathway in normal kidney are issues to be further explored. This review provides an update of these advances and their implications for our current understanding of the SLC14 UTs.

SLC13 family of Na⁺-coupled di- and tri-carboxylate/sulfate transporters

The SLC13 family comprises five genes (SLC13A1, SLC13A2, SLC13A3, SLC13A4, and SLC13A5) encoding structurally related multi-spanning transporters (8-13 transmembrane domains) with orthologues found in prokaryotes and eukaryotes. Mammalian SLC13 members mediate the electrogenic Na(+)-coupled anion cotransport at the plasma membrane of epithelial cells (mainly kidney, small intestine, placenta and liver) or cells of the central nervous system. While the two SLC13 cotransporters NaS1 (SLC13A1) and NaS2 (SLC13A4) transport anions such sulfate, selenate and thiosulfate, the three other SLC13 members, NaDC1 (SLC13A2), NaCT (SLC13A5) and NaDC3 (SLC13A3), transport di- and tri-carboxylate Krebs cycle intermediates such as succinate, citrate and α-ketoglutarate. All these transporters play a variety of physiological and pathophysiological roles in the different organs. Thus, the purpose of this review is to summarize the roles of SLC13 members in human physiology and pathophysiology and what the therapeutic perspectives are. We have also described the most recent advances on the structure, expression, function and regulation of SLC13 transporters.

Functional hoarseness in children: short-term play therapy with family dynamic counseling as therapy of choice

Children with nonorganic voice disorders (NVDs) are treated mainly using direct voice therapy techniques such as the accent method or glottal attack changes and indirect methods such as vocal hygiene and voice education. However, both approaches tackle only the symptoms and not etiological factors in the family dynamics and therefore often enjoy little success. The aim of the "Bernese Brief Dynamic Intervention" (BBDI) for children with NVD was to extend the effectiveness of pediatric voice therapies with a psychosomatic concept combining short-term play therapy with the child and family dynamic counseling of the parents. This study compares the therapeutic changes in three groups where different procedures were used, before intervention and 1 year afterward: counseling of parents (one to two consultations; n = 24), Brief Dynamic Intervention on the lines of the BBDI (three to five play therapy sessions with the child plus two to four sessions with the parents; n = 20), and traditional voice therapy (n = 22). A Voice Questionnaire for Parents developed by us with 59 questions to be answered on a four-point Likert scale was used to measure the change. According to the parents' assessment, a significant improvement in voice quality was achieved in all three methods. Counseling of parents (A) appears to have led parents to give their child more latitude, for example, they stopped nagging the child or demanding that he/she should behave strictly by the rules. After BBDI (B), the mothers were more responsive to their children's wishes and the children were more relaxed and their speech became livelier. At home, they called out to them less often at a distance, which probably improved parent-child dialog. Traditional voice therapy (C) seems to have had a positive effect on the children's social competence. BBDI seems to have the deepest, widest, and therefore probably the most enduring therapeutic effect on children with NVD.

Development of Values after Compulsory School: Work comes first, then family

During school-to-work transition, adolescents develop values and prioritize what is im-portant in their life. Values are concepts or beliefs about desirable states or behaviors that guide the selection or evaluation of behavior and events, and are ordered by their relative importance (Schwartz & Bilsky, 1987). Stressing the important role of values, career re-search has intensively studied the effect of values on educational decisions and early career development (e.g. Eccles, 2005; Hirschi, 2010; Rimann, Udris, & Weiss, 2000). Few re-searchers, however, have investigated so far how values develop in the early career phase and how value trajectories are influenced by individual characteristics. Values can be oriented towards specific life domains, such as work or family. Work values include intrinsic and extrinsic aspects of work (e.g., self-development, cooperation with others, income) (George & Jones, 1997). Family values include the importance of partner-ship, the creation of an own family and having children (Mayer, Kuramschew, & Trommsdroff, 2009). Research indicates that work values change considerably during early career development (Johnson, 2001; Lindsay & Knox, 1984). Individual differences in work values and value trajectories are found e.g., in relation to gender (Duffy & Sedlacek, 2007), parental background (Loughlin & Barling, 2001), personality (Lowry et al., 2012), educa-tion (Battle, 2003), and the anticipated timing of school-to-work transition (Porfeli, 2007). In contrast to work values, research on family value trajectories is rare and knowledge about the development during the school-to-work transition and early career development is lack-ing. This paper aims at filling this research gap. Focusing on family values and intrinsic work values and we expect a) family and work val-ues to change between ages 16 and 25, and b) that initial levels of family and work values as well as value change to be predicted by gender, reading literacy, ambition, and expected du-ration of education. Method. Using data from 2620 young adults (59.5% females), who participated in the Swiss longitudinal study TREE, latent growth modeling was employed to estimate the initial level and growth rate per year for work and family values. Analyses are based on TREE-waves 1 (year 2001, first year after compulsory school) to 8 (year 2010). Variables in the models included family values and intrinsic work values, gender, reading literacy, ambition and ex-pected duration of education. Language region was included as control variable. Results. Family values did not change significantly over the first four years after leaving compulsory school (mean slope = -.03, p =.36). They increased, however, significantly five years after compulsory school (mean slope = .13, p >.001). Intercept (.23, p < .001), first slope (.02, p < .001), and second slope (.01, p < .001) showed significant variance. Initial levels were higher for men and those with higher ambitions. Increases were found to be steeper for males as well as for participants with lower educational duration expectations and reading skills. Intrinsic work values increased over the first four years (mean slope =.03, p <.05) and showed a tendency to decrease in the years five to ten (mean slope = -.01, p < .10). Intercept (.21, p < .001), first slope (.01, p < .001), and second slope (.01, p < .001) showed signifi-cant variance, meaning that there are individual differences in initial levels and growth rates. Initial levels were higher for females, and those with higher ambitions, expecting longer educational pathways, and having lower reading skills. Growth rates were lower for the first phase and steeper for the second phase for males compared to females. Discussion. In general, results showed different patterns of work and family value trajecto-ries, and different individual factors related to initial levels and development after compul-sory school. Developments seem to fit to major life and career roles: in the first years after compulsory school young adults may be engaged to become established in one's job; later on, raising a family becomes more important. That we found significant gender differences in work and family trajectories may reflect attempts to overcome traditional roles, as over-all, women increase in work values and men increase in family values, resulting in an over-all trend to converge.

BPAG1a and b Associate with EB1 and EB3 and Modulate Vesicular Transport, Golgi Apparatus Structure, and Cell Migration in C2.7 Myoblasts.

BPAG1a and BPAG1b (BPAG1a/b) constitute two major isoforms encoded by the dystonin (Dst) gene and show homology with MACF1a and MACF1b. These proteins are members of the plakin family, giant multi-modular proteins able to connect the intermediate filament, microtubule and microfilament cytoskeletal networks with each other and to distinct cell membrane sites. They also serve as scaffolds for signaling proteins that modulate cytoskeletal dynamics. To gain better insights into the functions of BPAG1a/b, we further characterized their C-terminal region important for their interaction with microtubules and assessed the role of these isoforms in the cytoskeletal organization of C2.7 myoblast cells. Our results show that alternative splicing does not only occur at the 5' end of Dst and Macf1 pre-mRNAs, as previously reported, but also at their 3' end, resulting in expression of additional four mRNA variants of BPAG1 and MACF1. These isoform-specific C-tails were able to bundle microtubules and bound to both EB1 and EB3, two microtubule plus end proteins. In the C2.7 cell line, knockdown of BPAG1a/b had no major effect on the organization of the microtubule and microfilament networks, but negatively affected endocytosis and maintenance of the Golgi apparatus structure, which became dispersed. Finally, knockdown of BPAG1a/b caused a specific decrease in the directness of cell migration, but did not impair initial cell adhesion. These data provide novel insights into the complexity of alternative splicing of Dst pre-mRNAs and into the role of BPAG1a/b in vesicular transport, Golgi apparatus structure as well as in migration in C2.7 myoblasts.

In the aftermath of medical error : Caring for patients, family, and the healthcare workers involved

Medical errors, in particular those resulting in harm, pose a serious situation for patients ("first victims") and the healthcare workers involved ("second victims") and can have long-lasting and distressing consequences. To prevent a second traumatization, appropriate and empathic interaction with all persons involved is essential besides error analysis. Patients share a nearly universal, broad preference for a complete disclosure of incidents, regardless of age, gender, or education. This includes the personal, timely and unambiguous disclosure of the adverse event, information relating to the event, its causes and consequences, and an apology and sincere expression of regret. While the majority of healthcare professionals generally support and honest and open disclosure of adverse events, they also face various barriers which impede the disclosure (e.g., fear of legal consequences). Despite its essential importance, disclosure of adverse events in practice occurs in ways that are rarely acceptable to patients and their families. The staff involved often experiences acute distress and an intense emotional response to the event, which may become chronic and increase the risk of depression, burnout and post-traumatic stress disorders. Communication with peers is vital for people to be able to cope constructively and protectively with harmful errors. Survey studies among healthcare workers show, however, that they often do not receive sufficient individual and institutional support. Healthcare organizations should prepare for medical errors and harmful events and implement a communication plan and a support system that covers the requirements and different needs of patients and the staff involved.

The novel macrolide-Lincosamide-Streptogramin B resistance gene erm(44) is associated with a prophage in Staphylococcus xylosus.

A novel erythromycin ribosome methylase gene, erm(44), that confers resistance to macrolide, lincosamide, and streptogramin B (MLSB) antibiotics was identified by whole-genome sequencing of the chromosome of Staphylococcus xylosus isolated from bovine mastitis milk. The erm(44) gene is preceded by a regulatory sequence that encodes two leader peptides responsible for the inducible expression of the methylase gene, as demonstrated by cloning in Staphylococcus aureus. The erm(44) gene is located on a 53-kb putative prophage designated ΦJW4341-pro. The 56 predicted open reading frames of ΦJW4341-pro are structurally organized into the five functional modules found in members of the family Siphoviridae. ΦJW4341-pro is site-specifically integrated into the S. xylosus chromosome, where it is flanked by two perfect 19-bp direct repeats, and exhibits the ability to circularize. The presence of erm(44) in three additional S. xylosus strains suggests that this putative prophage has the potential to disseminate MLSB resistance.

Cloning of a protease gene family of Fasciola hepatica by the polymerase chain reaction

Degenerate oligonucleotide primers derived from conserved cysteine protease sequences were used in the reverse transcription polymerase chain reaction to amplify seven different cysteine protease cDNA clones, Fcp1-7, from RNA isolated from adult Fasciola hepatica. Five of the amplified F. hepatica sequences showed homology to the cathepsin L type and two were more related to the cathepsin B type. Southern blot analysis suggests that some members of this protease gene family are present in multiple copies. Northern blot analysis revealed differences in the levels of steady state mRNA expression for some of these proteases. The 5' and the 3' regions of Fcp1 were amplified using the rapid amplification of cDNA ends PCR protocol (RACE-PCR) and an additional clone was obtained by screening a lambda gt10 cDNA library using Fcp1 as a probe. The Fcp1 cDNA fragment was also subcloned in the expression vector pGEX and expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli. Antibodies, raised in rabbits against the GST:Fcp1 fusion protein, were used in western blot analysis to examine expression in different life-cycle stages of F. hepatica. In extracts from adult and immature parasites, the immune serum recognised predominantly two proteins of 30 kDa and 38 kDa. In other parasite stages, proteins of different molecular weight were recognised by the anti-GST:Fcp1 antiserum, indicating stage-specific gene expression or processing of Fcp1. In gelatine substrate gel analysis, strong proteolytic activity could be detected at 30 kDa, but not at 38 kDa, suggesting that the 30 kDa protein represents the mature enzyme and the 38 kDa protein the proenzyme.

A New Family of High-Affinity Transporters for Adenine, Cytosine, and Purine Derivatives in Arabidopsis

In many organisms, including plants, nucleic acid bases and derivatives such as caffeine are transported across the plasma membrane. Cytokinins, important hormones structurally related to adenine, are produced mainly in root apices, from where they are translocated to shoots to control a multitude of physiological processes. Complementation of a yeast mutant deficient in adenine uptake (fcy2) with an Arabidopsis cDNA expression library enabled the identification of a gene, AtPUP1 (for Arabidopsis thaliana purine permease1), belonging to a large gene family (AtPUP1 to AtPUP15) encoding a new class of small, integral membrane proteins. AtPUP1 transports adenine and cytosine with high affinity. Uptake is energy dependent, occurs against a concentration gradient, and is sensitive to protonophores, potentially indicating secondary active transport. Competition studies show that purine derivatives (e.g., hypoxanthine), phytohormones (e.g., zeatin and kinetin), and alkaloids (e.g., caffeine) are potent inhibitors of adenine and cytosine uptake. Inhibition by cytokinins is competitive (competitive inhibition constant Ki = 20 to 35 μM), indicating that cytokinins are transported by this system. AtPUP1 is expressed in all organs except roots, indicating that the gene encodes an uptake system for root-derived nucleic acid base derivatives in shoots or that it exports nucleic acid base analogs from shoots by way of the phloem. The other family members may have different affinities for nucleic acid bases, perhaps functioning as transporters for nucleosides, nucleotides, and their derivatives.