Publications by authors named "Poonam Sansanwal"

Nephropathic cystinosis, characterized by accumulation of cystine in the lysosomes, is caused by mutations in CTNS. The molecular and cellular mechanisms underlying proximal tubular dysfunction and progressive renal failure in nephropathic cystinosis are largely unclear, and increasing evidence supports the notion that cystine accumulation alone is not responsible for the end organ injury in cystinosis. We previously identified clusterin as potentially involved in nephropathic cystinosis.

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In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding.

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Background: Nephropathic cystinosis, a lysosomal storage disorder, is associated with generalized proximal tubular dysfunction and progressive renal failure. The underlying molecular and cellular mechanisms leading to renal tubular injury remain largely unknown. Abnormal induction of autophagy has been shown in cystinosis.

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Chronic allograft injury (CAI) results from a humoral response to mismatches in immunogenic epitopes between the donor and recipient. Although alloantibodies against HLA antigens contribute to the pathogenesis of CAI, alloantibodies against non-HLA antigens likely contribute as well. Here, we used high-density protein arrays to identify non-HLA antibodies in CAI and subsequently validated a subset in a cohort of 172 serum samples collected serially post-transplantation.

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Nephropathic cystinosis is a rare, inherited metabolic disease caused by functional defects of cystinosin associated with mutations in the CTNS gene. The mechanisms underlying the phenotypic alterations associated with this disease are not well known. In this study, gene expression profiles in peripheral blood of nephropathic cystinosis patients (N = 7) were compared with controls (N = 7) using microarray technology.

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Cystinosis, which is characterized by lysosomal accumulation of cystine in many tissues, was the first known storage disorder caused by defective metabolite export from the lysosome. The molecular and cellular mechanisms underlying nephropathic cystinosis, the most severe form, which exhibits generalized proximal tubular dysfunction and progressive renal failure, remain largely unknown. We used renal proximal tubular epithelial (RPTE) cells and fibroblasts from patients with three clinical variants of cystinosis: nephropathic, intermediate and ocular to explore the specific injury mechanism in nephropathic cystinosis.

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The molecular and cellular mechanisms underlying nephropathic cystinosis, which exhibits generalized proximal tubular dysfunction and progressive renal failure, remain largely unknown. Renal biopsies from patients with this disorder can reveal abnormally large mitochondria, but the relevance of this and other ultrastructural abnormalities is unclear. We studied the ultrastructure of fibroblasts and renal proximal tubular epithelial cells from patients with three clinical variants of cystinosis: Nephropathic, intermediate, and ocular.

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Nephropathic cystinosis is characterized clinically by generalized proximal renal tubular dysfunction, renal Fanconi Syndrome and progressive renal failure. Glomerular-proximal tubule disconnection has been noted in renal biopsies from patients with nephropathic cystinosis. In vitro studies performed in cystinotic fibroblasts and renal proximal tubular cells support a role for apoptosis of the glomerulotubular junction, and we have further extended these studies to human native cystinotic kidney specimens.

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Cathepsin L (ctsl), a lysosomal cyteine protease over expressed and secreted by cancer cells, has been implicated in a number of physiological and pathological processes including tumor cell proliferation and metastasis. In the present study we demonstrate that an unknown mRNA of human origin (Gene Bank accession number AF 217997) is a splice variant of human cathepsin L mRNA (hCATL A IV) and encodes a truncated form of cathepsin L (Deltactsl) containing only 151 C-terminal amino acids. This isoform is cytotoxic to the mammalian cells.

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A disparity remains between graft survival of renal allografts from deceased donors and from living donors. A better understanding of the molecular mechanisms that underlie this disparity may allow the development of targeted therapies to enhance graft survival. Here, we used microarrays to examine whole genome expression profiles using tissue from 53 human renal allograft protocol biopsies obtained both at implantation and after transplantation.

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