Blog
About

0
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found

      Comparison of Methods for Counting Cells in the Mouse Glomerulus

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background: Researchers have long been interested in counting the number of cells within the glomerulus. Investigators using different techniques have yielded conflicting results. The most direct method is to count the cells in serial sections from the entire glomerulus. This Exhaustive Count method is not usually practical. The disector/fractionator method counts the number of cells in a fraction of sections. The total is estimated from the product of the cell count and the reciprocal of the fraction. The Weibel-Gomez method determines the density of cells per glomerulus, then multiplies this density by glomerular volume to obtain cell number. In this study, we compared the disector/fractionator and Weibel-Gomez methods to identify a practical alternative for the time-consuming Exhaustive Count method. Methods: Glomeruli from a normal mouse kidney were completely sectioned and images obtained. Appropriate images were used to count glomerular cell number using each method. Results: The Exhaustive Count method yielded 213 ± 22 (mean ± SD) cells/glomerulus vs. the disector/fractionator average of 211 ± 29 cells/glomerulus (p = 0.82). The Weibel-Gomez method average of 235 ± 26 cells/glomerulus was statistically different from the Exhaustive Count method (p = 0.003). Conclusion: The Weibel-Gomez produced a 10% overestimation, whereas the disector/fractionator method was unbiased and thus a good substitute for the Exhaustive Count method.

          Related collections

          Most cited references 16

          • Record: found
          • Abstract: found
          • Article: not found

          Urinary excretion of podocytes in patients with diabetic nephropathy.

          Detection of podocytes in the urinary sediments of children with glomerulonephritis has been shown to indicate severe injury to the podocytes. The aim of the present study was to determine whether podocytes are present in the urine sediments of adult patients with diabetes with and without nephropathy and whether trandolapril is effective for podocyte injury. Fifty diabetic patients (10 with normoalbuminuria, 15 with microalbuminuria, 15 with macroalbuminuria and 10 with chronic renal failure) and 10 healthy controls were studied. Urinary podocytes were examined by immunofluorescence using monoclonal antibodies against podocalyxin, which is present on the surface of podocytes. In addition, we studied plasma metalloproteinase (MMP)-9 concentrations in all patients. Urinary podocytes were absent in healthy controls, diabetic patients with normoalbuminuria and diabetic patients with chronic renal failure. Podocytes were detected in the urine of eight diabetic patients with microalbuminuria (53%) and of 12 patients with macroalbuminuria (80%). The number of podocytes in the urine of patients with macroalbuminuria was significantly greater than in patients with microalbuminuria (P:<0.01). However, there was no relationship between urinary albumin excretion and urinary podocytes. In addition, plasma MMP-9 concentrations were significantly correlated with the number of urinary podocytes (P:<0.01). Twelve diabetic patients with macroalbuminuria and eight patients with microalbuminuria who had urinary podocytes were treated with the angiotensin-converting enzyme inhibitor trandolapril. Urinary albumin excretion, the number of podocytes and plasma MMP-9 concentrations were reduced by the trandolapril treatment. Podocytes in the urine may be a useful marker of disease activity in diabetic nephropathy. Trandolapril may be effective for podocyte injury.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Is podocyte injury relevant in diabetic nephropathy? Studies in patients with type 2 diabetes.

            Podocyte structural changes have been suggested to be involved in the pathogenesis of albuminuria in diabetes. We evaluated podocytes density, number, and structure in 67 white patients with type 2 diabetes: 21 normoalbuminuric (NA), 23 microalbuminuric (MA), and 23 proteinuric (P). Kidney function and biopsy studies were performed; 20 kidney donors served as control subjects. Electron microscopic morphometric analysis was used to estimate numerical density of podocytes per glomerulus [Nv(epi/glom)], filtration slit length density per glomerulus (FSLv/glom), and foot process width (FPW). The number of podocytes per glomerulus (Epi N/glom) was obtained by multiplying Nv(epi/glom) by mean glomerular volume. Nv(epi/glom) was significantly decreased in all type 2 diabetic groups compared with control subjects and was lower in MA and P than in NA (P < 0.0001, ANOVA). Epi N/glom was lower in MA and P patients compared with control subjects (P < 0.002, ANOVA); however, there were no significant differences among the type 2 diabetic groups. In addition, MA and P had decreased FSLv/glom and increased FPW compared with NA (P < 0.005 for both, ANOVA). The albumin excretion rate was inversely related to Nv(epi/glom) and FSLv/glom and directly to FPW (P < 0.0005 for all), whereas there was no correlation with Epi N/glom. In conclusion, changes in podocyte structure and density occur since the early stages of diabetic nephropathy and might contribute to increasing albuminuria in type 2 diabetic patients. These findings also suggest that in white type 2 diabetic patients, the density of podocytes may be functionally more relevant than the absolute number.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Podocytopenia and disease severity in IgA nephropathy.

              IgA nephropathy is a common form of progressive glomerular disease, associated with proliferation of mesangial cells and mesangial deposition of IgA. The present study was designed to investigate functional and morphological covariates of disease severity in patients with IgA nephropathy. Glomerular hemodynamics, permselectivity and ultrastructure were studied in 17 adult patients with IgA nephropathy using inulin, para-aminohippuric acid (PAH) and 3H-Ficoll clearances and morphometric methods. A mathematical model of macromolecule permeation through a heteroporous membrane was used to characterize glomerular permselectivity. Controls consisted of 14 healthy living kidney donors and 12 healthy volunteers. The patients were heterogeneous in their disease severity, but as a group had a decreased glomerular filtration rate (GFR) and increased urinary protein excretion compared to controls [63 +/- 29 SD vs. 104 +/- 23 mL/min/1.73 m2, P < 0.001, and (median) 1.34 vs. 0.11 g/day, P < 0.0001, respectively). A multivariate analysis of structural and functional relationships revealed GFR depression to be most strongly correlated with the prevalence of global glomerular sclerosis (t = -4.073, P = 0.002). Those patients with the most severe glomerular dysfunction had a reduced number of glomerular visceral epithelial cells (podocytes) per glomerulus. The degree of podocytopenia was related to the extent of glomerular sclerosis and of impairment of permselectivity and GFR, with worsening injury below an apparent threshold podocyte number of about 250 cells per glomerulus. There were no corresponding correlations between these indices of injury and the number of mesangial and endothelial cells. Our findings show that podocyte loss is a concomitant of increasing disease severity in IgA nephropathy. This suggests that podocyte loss may either cause or contribute to the progressive proteinuria, glomerular sclerosis and filtration failure seen in this disorder.
                Bookmark

                Author and article information

                Journal
                NEE
                Nephron Exp Nephrol
                10.1159/issn.1660-2129
                Cardiorenal Medicine
                S. Karger AG
                1660-2129
                2006
                July 2006
                24 April 2006
                : 103
                : 4
                : e139-e148
                Affiliations
                aDepartment of Pediatrics, University of Minnesota, Minneapolis, Minn., bDepartment of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, Calif., USA; cStereology and Electron Microscopy Laboratory and MIND Center, University of Aarhus, Aarhus, Denmark
                Article
                92905 Nephron Exp Nephrol 2006;103:e139–e148
                10.1159/000092905
                16636586
                © 2006 S. Karger AG, Basel

                Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

                Page count
                Figures: 6, Tables: 3, References: 33, Pages: 1
                Product
                Self URI (application/pdf): https://www.karger.com/Article/Pdf/92905
                Categories
                Original Paper

                Comments

                Comment on this article