G A Herrera

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..This review highlights the role that electron microscopy has played and continues playing in the characterization of plasma cell dyscrasias-related renal lesions...

..Renal dysfunction in plasma cell dyscrasias is common. It is the second most common cause of death in patients with myeloma...

..Management of patients with polyoma virus nephropathy is difficult since there is no specific antiviral therapy available at this time...

..Pathologists should be aware of the entire immuno-morphological spectrum associated with melanocytic neoplasms to be able to address diagnostic difficulties that may, arise as a consequence of the heterogeneity of these tumors...

..In some of these patients, electron microscopy provides key information that cannot be otherwise obtained...

..Using this in vitro model, it is then possible to delineate the LC interactions with putative receptors at the mesangial cell surface that regulate mesangial cell pathobiologic responses and mesangial matrix homeostasis...

..We review here the heterogeneity of CD-30-positive neoplasms (so-called anaplastic large cell Ki-1 lymphomas)...

..The other possible indications are much more controversial. This paper summarizes and critically reviews the literature available on this subject and defines recommendations based on the information available at the current time...

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..An attempt is made to address histogenesis/differentiation issues that would help in understanding morphologic findings, with an emphasis placed on the role that ultrastructural evaluation has played in demonstrating these...

..Dissecting the events taking place when G-LC interact with MC may define potential important targets for selective therapeutic manipulation to ameliorate or prevent the glomerular injury that ensues...

..The present chapter will address the pathogenesis of these disorders with an emphasis on highlighting crucial steps possibly amenable to therapeutic intervention to stop or ameliorate adverse consequences leading to irreversible changes...

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..Data obtained in this study highlighted that HMCs incubated with LCDD-LCs undergo a myofibroblastic phenotypic transformation, while AL-Am-LCs induce a macrophage-like phenotype in these cells...

..CONCLUSIONS: The data demonstrated the low sensitivity of immunofluorescence microscopy in the detection of AL-amyloidosis in the kidney and underscore the need to pursue additional diagnostic studies to identify this problem...

..86 and 0.97, respectively). These results indicate that eIF4E stain intensity may be useful as a marker for cervical neoplasia...

..adenocarcinoma, and the origin of adenocarcinomas of unknown primary. The authors discuss how they approach these diagnostic problems in their everyday practice and how they incorporate EM in solving them...

..The patient underwent chemotherapy for 4 months and subsequently a partial liver resection was performed. This case illustrates the important role of electron microscopy in evaluating small round cell tumors in children...

..Correlative light microscopic studies are often useful, however, and will be described as well...

..We also point out matrical fibrillary deposits that may mimic some of the above entities at the ultrastructural level. Emphasis is placed, through comparative illustrations, on the prominent role of electron microscopy...

..Electron microscopy can be crucial in providing information either to support a diagnosis of IgA nephropathy or to aid in the diagnosis of one of its mimics...

..Cocaine-mediated endothelial injury and platelet activation may play important pathogenetic roles in cocaine abusers who develop acute renal failure and malignant hypertension...

..It must be emphasized that in some patients the plasma cell dyscrasia does not become clinically manifested until years after the diagnosis of light chain crystal deposition...

..A combined approach using electron microscopic and immunohistochemical evaluation can be utilized effectively to identify BK virus-associated nephropathy at an early phase facilitating early clinical intervention...

..However, in the last few years a new generation of animal models has emerged to address whether what has been documented in vitro retains significance in vivo. Preliminary observations appear to substantiate this...

..Recognition of this unusual pattern of renal disease in patients with plasma cell dyscrasia requires ancillary diagnostic techniques...

..FISH and IHC analysis of EGFR, possibly along with other tumor markers, may be a useful ancillary tool to classify difficult cytology cases and inform clinicians arranging targeted chemotherapy...

..A description of the pathobiology and overview of the approach to management of these light chain-mediated renal lesions is provided...

..Ultrastructurally, the crystals appear to be located within lysosomes. No deposits of light-chains were seen elsewhere in the kidney biopsy...

..The mesangium is either replaced or expanded depending on the light chains involved in the pathologic process...

..The potential for bone marrow-derived cells to differentiate into mesangial cells and repopulate damaged mesangium, thus "healing" what is today considered to be irreversible damage represents an exciting new area of research...

..64%). A case of aminoglycoside toxicity revealed casts with myeloid bodies. Ultrastructural evaluation of casts may provide useful information that may be critical to establish or suggest a specific diagnosis...

..Alterations of the mesangial ECM in AL-amyloidosis (AL-Am) and light chain deposition disease (LCDD) are crucial in their pathogeneses as two divergent entities...

..Furthermore, this type of amyloidosis shares the same morphologic features with other types of amyloidosis and can involve the kidney to produce nephrotic syndrome...

..The incorporation of both technologies resulted in turnaround times being reduced to 4 h or less...

..Furthermore, the data also reveal that PDGF-beta and TGF-beta act independently and that PDGF-beta activation by itself cannot increase ECM proteins directly, but only by increasing the number of HMCs...

..The data also demonstrated that cubilin and megalin were absent on MCs, so the receptor involved is different from the one already characterized in the proximal tubules...

..Down-regulation of E-CD may be one of the pathways responsible for tumor differentiation and may promote deeper invasion in urothelial carcinomas...

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..The diagnosis of cast nephropathy in a patient with Waldenström's macroglobulinemia was made. She underwent treatment with fludarabine and plasmapheresis/hemodialysis with dramatic improvement of her renal function...