Stem cell marker TRA-1-60 is expressed in foetal and adult kidney and upregulated in tubulo-interstitial disease
ABSTRACT The kidney has an intrinsic ability to repair itself when injured. Epithelial cells of distal tubules may participate in regeneration. Stem cell marker, TRA-1-60 is linked to pluripotency in human embryonic stem cells and is lost upon differentiation. TRA-1-60 expression was mapped and quantified in serial sections of human foetal, adult and diseased kidneys. In 8- to 10-week human foetal kidney, the epitope was abundantly expressed on ureteric bud and structures derived therefrom including collecting duct epithelium. In adult kidney inner medulla/papilla, comparisons with reactivity to epithelial membrane antigen, aquaporin-2 and Tamm-Horsfall protein, confirmed extensive expression of TRA-1-60 in cells lining collecting ducts and thin limb of the loop of Henle, which may be significant since the papillae were proposed to harbour slow cycling cells involved in kidney homeostasis and repair. In the outer medulla and cortex there was rare, sporadic expression in tubular cells of the collecting ducts and nephron, with positive cells confined to the thin limb and thick ascending limb and distal convoluted tubules. Remarkably, in cortex displaying tubulo-interstitial injury, there was a dramatic increase in number of TRA-1-60 expressing individual cells and in small groups of cells in distal tubules. Dual staining showed that TRA-1-60 positive cells co-expressed Pax-2 and Ki-67, markers of tubular regeneration. Given the localization in foetal kidney and the distribution patterns in adults, it is tempting to speculate that TRA-1-60 may identify a population of cells contributing to repair of distal tubules in adult kidney.
Conference Paper: New product technology decisions in the US multi-market firm[Show abstract] [Hide abstract]
ABSTRACT: Decision-making processes regarding new product technology in multiproduct organizations have been examined from three different perspectives: the chief executive officer (CEO), the chief operating officer (COO), and the chief technology officer (CTO). The study is a follow-on to initial exploratory research in this area and is based on data from 150 Fortune 500 companies that where selected because they listed their R&D spending in the firm's annual report and the SEC's 10 K. Three related, but different, questionnaires were sent to the CEO, the COO, and the CTO of these firms. The research hypothesis is that technically educated CEOs and COOs play a greater role in new product technology decision making in their firms and that these firms consider themselves technology leaders or at least strong technology followers. It is further hypothesized that the role of the CTO differs depending on the educational background of the CEO and COO. In addition, the use of a science advisory committee in such firms is explored. The findings are presented and discussed in detailTechnology Management : the New International Language; 11/1991
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ABSTRACT: The computation of the geometrical parameters identification model of a robot arm leads to an intrinsic extended Jacobian matrix. This matrix is often singular and its manual computation is tedious and may lead to error. A computer assisted procedure is developed to compute this matrix symbolically and to check its singularity. The program GPIM is developed in Pascal and works on PC's for this purpose. Jacobian singularity is checked using its symbolic expressions with the aid of a proposed table for robot arm parameters to obtain a minimum set of identified parameters. This program can be used for simple chain robot arms having revolute (R) and/or prismatic (P) joints including the case of consecutive near parallel axes. TH8 robot arm of type RPPRRR having two pairs of consecutive near parallel axes is studied to show the program efficiency and how singularity is eliminated.Journal of Intelligent and Robotic Systems 06/1996; 16:103-121. DOI:10.1007/BF00449701 · 0.81 Impact Factor
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ABSTRACT: This review summarizes recent advances in histochemistry and cell biology which complement and extend our knowledge regarding various aspects of protein functions, cell and tissue biology, employing appropriate in vivo model systems in conjunction with established and novel approaches. In this context several non-expected results and discoveries were obtained which paved the way of research into new directions. Once the reader embarks on reading this review, it quickly becomes quite obvious that the studies contribute not only to a better understanding of fundamental biological processes but also provide use-oriented aspects that can be derived therefrom.Histochemie 02/2011; 135(2):111-40. DOI:10.1007/s00418-011-0781-7 · 2.93 Impact Factor