No abstract available.
Glomerular Basement Membrane*

Normal human glomerular basement membrane (GBM) and mesangial matrix (MM) contain several different basement membrane components in varying degrees. The characteristic morphological and ultrastructural changes in patients with diabetic nephropathy are the thickening of the GBM and the expansion of the MM. In order to investigate the changes of extracellular matrix components in diabetes, the immunohistochemical localization was performed in 17 cases with different degrees using antisera to human collagen types I, III, IV, VI, fibronectin, and laminin. The following results were obtained: 1. The reactivity for collagen IV was increased in expanded MM in the diffuse glomerulosclerosis (GS). With the progression to the nodule formation, collagen IV was prominently decreased in the peripheral area of the nodules. 2. Collagen VI was increased in GBM and MM in the diffuse GS, it was especially prominent in the expanded MM. With the progression to nodule formation, collagen VI was prominently increased in the periphery of the nodules. 3. Interstitial collagen I and III were not stained in many of the cases with the diffuse GS. With the progression to nodule formation, these were slightly expressed. A lamellar pattern of positive reaction was noted at the periphery of the late nodular lesions. 4. Fibronectin was increased in GBM & MM in the diffuse GS, it was especially intense in the MM. With the progression to the nodule formation, the reactivity of antibody to the fibronectin was decreased. 5. Laminin was weakly stained along the GBM & trace in the MM, but was not changed in the nodular GS. In summary, the expanded mesangial matrix in the diffuse GS showed a markedly increased staining for collagen IV, fibronectin and collagen VI. Less intense linear staining for collagen VI, fibronectin, laminin, collagen IV and collagen III was noted along the GBM. In the nodular GS, the composition of the early nodules resembled that of the diffuse GS. However, the late nodular lesion of the nodular GS revealed decreased reactivity for collagen IV and fibronectin at the periphery of the nodule, where collagen VI and interstitial collagen I and III were increased in laminated pattern.
Basement Membrane ; Collagen ; Diabetic Nephropathies* ; Extracellular Matrix* ; Fibronectins ; Glomerular Basement Membrane ; Humans ; Immune Sera ; Laminin

The thickness of the glomerular basement membrane may vary not only in glomerular disease, but also in normal persons according to age and sex. But there has been no data on the normal thickness of the basement membrane in Korea. This study was designed to determine the glomerular basement membrane thickness as a reference value according to age and sex, in 50 cases of minimal change disease obtained from patients aged 2~67 years. Measurement of glomerular basement membrane was made on electron micrograph using an image analyzer. The thickness of each case was estimated by the arithmetic and harmonic mean methods. The mean thickness of the glomerular basement membrane was 291.9 47.9 nm by harmonic mean method and 284.2 43.7 nm by arithmetic mean method. And the harmonic mean thickness of the glomerular basement membrane according to age was 249.1 32.5 nm (1~5 years), 256.6 45.3 nm (6~10 years), 279.2 57.9 nm (11~15 years), 303.2 43.8 nm (16~20 years), 335.3 37.5 nm (21~30 years), and 291.1 22.5 nm (over 30 years), respectively. There was a trend that the thickness of glomerular basement membranes increased with the age till 30 years of age. There was no significant sex-related difference. In conclusion, the mean glomerular basement membrane thickness is comparable to the data from western people and shows a trend of increasing thickness according to the age.
Basement Membrane ; Glomerular Basement Membrane* ; Humans ; Kidney ; Korea ; Nephrosis, Lipoid* ; Reference Values

Thin basement membrane disease is defined as diffuse thinning of the glomerular basement membrane, and is clinically characterized by persistent hematuria, minimal proteinuria, normal renal function, and a benign course. It can occur together with other glomerular diseases. We experienced a case of thin basement membrane disease concurrent with minimal-change disease. Treatment with corticosteroid resulted in improved proteinuria and peripheral edema during the follow-up period.
Basement Membrane ; Edema ; Follow-Up Studies ; Glomerular Basement Membrane ; Hematuria ; Nephrosis, Lipoid ; Proteinuria

No abstract available.
Glomerular Basement Membrane* ; Heparan Sulfate Proteoglycans* ; Heparitin Sulfate*

=Abstract= Membranoproliferative glomerulonephritis (MPGN) is a progressive primary glomerulonephritis characterized by mesangial proliferation with increased mesangial matrix, subendothelial immune deposits, mesangial interposition and a double contour feature of the glomerular basement membrane. The glomerular involvement in MPGN is usually diffuse; however, cases of focal or segmental MPGN have been reported by several authors. We report a case of focal segmental MPGN with prolonged hypocomplementemia for 3 years in a 5 years old girl.
Child, Preschool* ; Female* ; Glomerular Basement Membrane ; Glomerulonephritis ; Glomerulonephritis, Membranoproliferative* ; Humans

Anatomical examinations on Bruch's membrane have almost been by light microscopy or transmission electron microscopy. Scanning electron microscopy allowed us to evaluate surface features topographically. Each layer of Bruch's membrane was exposed sequentially to mechanical or enzymatic treatment of the retinal pigment epithelium choroid complex from human cadavar eye. The authors examined the surface features of the membrane by dry-cracking scanning electron microscopy. The basement membrane of retinal pigment epithelium appeared like a smooth thin plastic membrane which was framed by collagen fibers. The inner collagenous layer was composed of many collagen fiber bundles which were placed in order and the ground substance between them was not visible. Elastic layer of Burch's membrane appeared to be coarse and fine fibers matted together by some amorphous substance. This layer had many openings on its solid sheet and the outer collagenous zone was visible though these openings.
Basement Membrane ; Bruch Membrane* ; Choroid ; Collagen ; Humans* ; Membranes ; Microscopy ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Plastics ; Retinal Pigment Epithelium

PURPOSE: To evaluate the effect of adding exogenous extracellular matrix (ECM) proteins on the reattachment of retinal pigment epithelium (RPE) to the damaged surface of Bruch's membrane (BM). METHODS: Porcine BM explants were divided into six groups: BMs with an intact basal lamina (bl-BM) and five damaged BMs (d-BM: bare & four ECM-coated). The d-BM was coated with ECM proteins (either fibronectin, laminin, collagen IV, or all). Primary RPE sheets were plated and cultured for each group of BM explants. The attached live cells were counted and examined with a scanning electron microscope after three days, as well as at 1, 2 and 4 weeks. RESULTS: The RPE reattachment rate was highest in bl-BM and lowest in uncoated d-BM. ECM-coated groups showed a lower reattachment rate than bl-BM, but when compared with the uncoated group, the reattachment rate was significantly increased (p<0.05). ECM-exposure time did not influence the reattachment rate of any of the groups. RPE cells plated on bl-BMs and ECM-coated d-BMs attached and proliferated well and achieved confluence over time. Even though most cells were flat and large in shape, some cells revealed a good morphology with microvilli on their surface. On the other hand, only some of the RPE sheets plated on the uncoated d-BM attached loosely and most cells remained round and clumped. CONCLUSIONS: These results show that the addition of ECM proteins may increase the ability of RPE cells to reattach to the damaged BM surface, which would likely create a good morphology.
Basement Membrane ; Bruch Membrane ; Collagen ; Epithelial Cells* ; Extracellular Matrix Proteins* ; Extracellular Matrix* ; Fibronectins ; Hand ; Laminin ; Microvilli ; Retinal Pigment Epithelium ; Retinaldehyde*

Drusen are small, yellowish deposits that form under the retinal pigment epithe lium with senescence or under certain pathological conditions. The present study examined these structures under the scanning electron microscope. Tissue came from the eyes of four donors, who were 22, 56, 60 and 61 years of age and who demonstrated widespread drusen of the posterior fundus. which was noted on postmortem examination. Specimens were prepared by detaching the retinal pig ment epithelium from Bruch's membrane and freeze fracturing the tissue. Drusen appeared as follows: 1. Distinct spherical masse, 10 X 9 um and 9 X 7 um in size, were situated between basement membrane of the retinal pigment epithelium and Bruch's membrane. The surface of the spherical masses were smooth. 2. Indistinct globular dome-like masses, with a harsh surface, were situated bet ween basement membrane of the retinal pigment epithelium and Bruch's membrane. These masses varied greatly in size. 3. Localized of dispersed small granular deposits of the inner collagen layer of Bruch's membrane were noted.
Aging ; Autopsy ; Basement Membrane ; Bruch Membrane ; Collagen ; Epithelium ; Freeze Fracturing ; Humans* ; Microscopy, Electron, Scanning* ; Retinal Pigment Epithelium ; Retinaldehyde ; Tissue Donors

IgA nephropathy and thin basement membrane disease are common glomerular diseases in persistent microscopic hematuria with or without proteinuria. However, these two conditions cannot be easily distinguished on the biochemical or urinary findings alone. Therefore, renal biopsy is required for correct identification of the two conditions in most cases. Recently, it has been reported that thinning of glomerular basement membrane is accompanied with precipitation of electron dense deposits in some patients with IgA nephropathy. We report a case of IgA nephropathy associated with thin basement membrane disease in a 19-year-old male with microscopic hematuria and mild proteinuria. After 2 years' treatment with angiotensin II receptor blocker, the patient exhibited persistent microscopic hematuria but decreased proteinuria. Our finding concurs with the previous reports indicating that patients with both IgA nephropathy and thin basement membrane disease do not have different clinical features compared to those with IgA nephropathy alone. In addition, clinical outcome does not appear to be affected by thin basement membrane disease when these two conditions are combined.
Basement Membrane ; Biopsy ; Electrons ; Glomerular Basement Membrane ; Glomerulonephritis, IGA ; Hematuria ; Humans ; Immunoglobulin A ; Male ; Proteinuria ; Receptors, Angiotensin ; Young Adult