Cadherin-9 Is a Novel Cell Surface Marker for the Heterogeneous Pool of Renal Fibroblasts

BACKGROUND: Interstitial fibroblasts are a minor, but nevertheless very important, component of the kidney. They secrete and remodel extracellular matrix and they produce active compounds such as erythropoietin. However, studying human renal fibroblasts has been hampered by the lack of appropriate surface markers. METHODS AND FINDINGS: The expression of cadherin-9 in various human renal cell lines and tissues was studied on the mRNA level by RT-PCR and on the protein level with the help of newly generated cadherin-9 antibodies. The classical type II cadherin-9, so far only described in the neural system, was identified as a reliable surface marker for renal fibroblasts. Compared to FSP1, a widely-used cytosolic renal fibroblast marker, cadherin-9 showed a more restricted expression pattern in human kidney. Under pathological conditions, cadherin-9 was expressed in the stroma of renal cell carcinoma, but not in the tumor cells themselves, and in renal fibrosis the percentage of cadherin-9-positive cells was clearly elevated 3 to 5 times compared to healthy kidney tissue. Induction of epithelial mesenchymal transition in renal epithelial cells with cyclosporin-A, which causes renal fibrosis as a side effect, induced cadherin-9 expression. Functional studies following siRNA-mediated knockdown of cadherin-9 revealed that it acts in the kidney like a typical classical cadherin. It was found to be associated with catenins and to mediate homophilic but not heterophilic cell interactions. CONCLUSIONS: Cadherin-9 represents a novel and reliable cell surface marker for fibroblasts in healthy and diseased kidneys. Together with the established marker molecules FSP1, CD45 and alpha smooth muscle actin, cadherin-9 can now be used to differentiate the heterogenic pool of renal fibroblasts into resident and activated fibroblasts, immigrated bone marrow derived fibroblast precursors and cells in different stages of epithelial mesenchymal transition

Social navigation

In this chapter we present one of the pioneer approaches in supporting users in navigating the complex information spaces, social navigation support. Social navigation support is inspired by natural tendencies of individuals to follow traces of each other in exploring the world, especially when dealing with uncertainties. In this chapter, we cover details on various approaches in implementing social navigation support in the information space as we also connect the concept to supporting theories. The first part of this chapter reviews related theories and introduces the design space of social navigation support through a series of example applications. The second part of the chapter discusses the common challenges in design and implementation of social navigation support, demonstrates how these challenges have been addressed, and reviews more recent direction of social navigation support. Furthermore, as social navigation support has been an inspirational approach to various other social information access approaches we discuss how social navigation support can be integrated with those approaches. We conclude with a review of evaluation methods for social navigation support and remarks about its current state

The Dopamine Augmenter L-DOPA Does Not Affect Positive Mood in Healthy Human Volunteers

Dopamine neurotransmission influences approach toward rewards and reward-related cues. The best cited interpretation of this effect proposes that dopamine mediates the pleasure that commonly accompanies reward. This hypothesis has received support in some animal models and a few studies in humans. However, direct assessments of the effect of transiently increasing dopamine neurotransmission have been largely limited to the use of psychostimulant drugs, which elevate brain levels of multiple neurotransmitters in addition to dopamine. In the present study we tested the effect of more selectively elevating dopamine neurotransmission, as produced by administration of the immediate dopamine precursor, L-DOPA (0, 100/25, 200/50 mg, Sinemet), in healthy human volunteers. Neither dose altered positive mood. The results suggest that dopamine neurotransmission does not directly influence positive mood in humans

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is the most common acute hyperglycaemic emergency in people with diabetes mellitus. A diagnosis of DKA is confirmed when all of the three criteria are present — ‘D’, either elevated blood glucose levels or a family history of diabetes mellitus; ‘K’, the presence of high urinary or blood ketoacids; and ‘A’, a high anion gap metabolic acidosis. Early diagnosis and management are paramount to improve patient outcomes. The mainstays of treatment include restoration of circulating volume, insulin therapy, electrolyte replacement and treatment of any underlying precipitating event. Without optimal treatment, DKA remains a condition with appreciable, although largely preventable, morbidity and mortality. In this Primer, we discuss the epidemiology, pathogenesis, risk factors and diagnosis of DKA and provide practical recommendations for the management of DKA in adults and children