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Biomedical subjects

H Koide

Publications and source records attributed to H Koide.

At least 145 records · Page 8Linked to original sources

Ultrastructural changes in glomerular epithelial cells in acute puromycin aminonucleoside nephrosis: a study by high-resolution scanning electron microscopy.

Ultrastructural changes in the podocytes were studied during the development of, and recovery from, acute puromycin aminonucleoside (PAN) nephrosis using high-resolution scanning electron microscopy (hrSEM) and transmission electron microscopy (TEM). In the process of development of PAN nephrosis, four types of early structural changes were observed before total loss of foot processes: formation of cytoplasmic blebs, masking of filtration clefts, flattening of foot processes, and retraction of foot processes. The masking of filtration clefts visualized by hrSEM corresponded to the multiplication of slit diaphragms and adhesion of foot processes in the TEM findings, and preceded retraction of the foot processes. Changes of podocyte configuration were produced. Recovery from this change of podocyte configuration began as islands of podocyte interdigitation, and was proceeded by expansion of the islands. During recovery, the primary processes were re-established either by retraction or perforation of the thin cytoplasm after the formation of foot processes. We conclude that loss of foot processes begins with the masking of filtration clefts. Recovery from the change in podocyte configuration begins with the formation of new foot processes.

Acute Disease↗

Widening of capillary neck and alteration of extracellular matrix ultrastructure in diabetic rat glomerulus as revealed by computer morphometry and improved tissue processing.

Morphological and morphometric studies of glomeruli were carried out in streptozotocin-induced diabetic rats using improved tissue processing and computerized morphometry. Increased mesangial matrix, occupying the enlarged diabetic mesangium, contained an abundance of dark granular material in addition to the microfibrils which were usually found in the control glomeruli. In the diabetic glomeruli, the lamina densa was thick and heterogeneous showing a dense layer both on its epithelial and endothelial aspects, and the lamina rara externa contained more fibrils than in control rats. Detailed estimation of the absolute values of the various compartments of the diabetic glomeruli by using perfusion-fixed materials and a computer-assisted digitizer revealed that the volume and surface area of the mesangium were increased more extensively than those of the capillary; the enlargement of the mesangial-capillary interface area was the most pronounced among the morphometric changes of the diabetic glomeruli; and that the moderate increase in capillary volume was associated with an increased radius. Our quantitative results showed that capillaries in the diabetic glomeruli had an extensively wider neck which may be the first sign of structural damage to the glomerular tuft.

Animals↗

Effect of monoclonal antibody CD4 on glomerulonephritis of ddY mice, a spontaneous animal model of IgA nephropathy.

Immunopathological studies were performed to determine whether the glomerular injuries in ddY mice, a model for IgA nephropathy (Berger's disease), are influenced by treatment with a rat monoclonal antibody (mAb) to murine CD4 molecules. The ddY mice were initially treated with intravenous injections, followed by weekly intraperitoneal injections of mAb CD4. Flow cytometry analysis showed that there was a marked decrease in the number of CD4+ T cells. In immunofluorescence, the mean intensity of IgA deposits in the renal glomerular mesangial areas and capillary walls of the treated ddY mice was significantly lower than that in saline-treated control mice of comparable ages. Glomerular mesangial expansion in the treated mice was milder than that found in the saline control mice. However, no significant differences in the level of serum IgA, urinary protein, and average number of intraglomerular cells between the treated and control ddY mice were observed. Thus, it appears that although CD4+ T cells control the amount of IgA deposits in glomeruli, other factors may be involved in the evolution of IgA nephropathy in ddY mice.

Animals↗

Altered glomerular steady-state levels of tumour necrosis factor-alpha mRNA during nephrotic and sclerotic phases of puromycin aminonucleoside nephrosis in rats.

1. We determined glomerular and medullary tumour necrosis factor-alpha mRNA levels in acute puromycin aminonucleoside nephrosis on days 0, 8 and 20. 2. Tumour necrosis factor-alpha mRNA levels were increased fourfold in glomeruli and twofold in the medulla during the nephrotic stage of acute puromycin aminonucleoside nephrosis (day 8). 3. The high tumour necrosis factor-alpha mRNA levels in both glomeruli and the medulla were ameliorated significantly by methylprednisolone administration. 4. Focal glomerular sclerosis was induced in rats by injection of puromycin aminonucleoside on days 0, 27, 34 and 41 and by unilateral nephrectomy on day 22. 5. The percentage of sclerosing glomeruli was 16.6% on day 48 and had increased significantly to 72.8% on day 80. 6. During the sclerotic phase of puromycin amino-nucleoside nephrosis, glomerular tumour necrosis factor-alpha mRNA levels increased as glomerular sclerosis progressed. On day 80, glomerular tumour necrosis factor-alpha mRNA levels were 13-fold higher than levels in control rats. 7. These data suggest that glomerular tumour necrosis factor-alpha mRNA expression is associated with the development of puromycin aminonucleoside-induced glomerular sclerosis.

Acute Disease↗

Gene expression of metalloproteinases and their inhibitor in renal tissue of New Zealand black/white F1 mice.

1. The present study was carried out to determine how levels of the mRNA of metalloproteinases (metalloproteinase-1, 72 kDa type IV collagenase, metalloproteinase-3 and 92 kDa type IV collagenase) and tissue inhibitor of metalloproteinases are regulated in the renal tissues of New Zealand Black/White F1 mice. 2. mRNA levels for metalloproteinase-1, 72 kDa type IV collagenase, metalloproteinase-3 and tissue inhibitor of metalloproteinases increased significantly with the progression of nephritis in New Zealand Black/White F1 mice. 3. At 48 weeks of age, the levels of mRNA for metalloproteinase-1, 72 kDa type IV collagenase, metalloproteinase-3 and tissue inhibitor of metalloproteinases increased by 8-, 4-, 8- and 15-fold, respectively, in the renal tissues of New Zealand Black/White F1 mice compared with New Zealand White mice. 4. In the kidneys of New Zealand White mice, however, the mRNA levels of these proteins changed little throughout the experimental period. 5. We could not detect expression of mRNA for 9 2 kDa type IV collagenase in the renal tissue of New Zealand Black/White F1 mice at 8 weeks of age or in New Zealand White mice at 8, 24 or 48 weeks of age, whereas we could detect expression of mRNA for this protein in New Zealand Black/White F1 mice at 24 and 48 weeks of age when mononuclear cells had infiltrated the interstitium and surrounding blood vessels. 6. At 24 weeks of age, New Zealand Black/White F1 mice were divided into two groups and received either methylprednisolone or saline injection for 24 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

West syndrome with cerebellar porencephalus.

The authors report six very low birth weight newborn infants who had RDS, IVH and cerebellar porencephalus and later suffered from West syndrome. Four of them have been followed up to the present time and have had MRI scans performed. Their present clinico-neurological features and MRI findings are described. The authors also raise the possibility of prevention of mental deterioration if anticipatory treatment is started early. Very low birth weight newborn infants with cerebellar porencephalus should be observed more carefully with clinical and EEG examinations to detect infantile spasms earlier and to protect them from further mental deterioration.

Age of Onset↗

Diffuse proliferative glomerulonephritis with hepatitis C virus-like particles in paramesangial dense deposits in a patient with chronic hepatitis C virus hepatitis.

A 62-year-old man with hepatitis C virus (HCV) infection developed proliferative glomerulonephritis with IgM and C3 deposits. Electron microscopy showed HCV-like particles in the paramesangial dense deposits, which are similar in shape to HCV previously described. These findings suggest HCV-related proliferative glomerulonephritis.

Chronic Disease↗

Effect of parathyroid-hormone-related protein on sodium-dependent phosphate transport in renal brush border membrane vesicles in rats. Comparison with parathyroid hormone.

Parathyroid-hormone-related protein (PTHrP) has significant homology with parathyroid hormone (PTH) in the amino-terminal region. We compared the effects of synthetic human PTHrP [hPTHrP(1-34)] on Na(+)-dependent phosphate transport with those of synthetic human PTH [hPTH(1-34)]. Intravenous administration of hPTHrP(1-34) in parathyroidectomized rats caused hypercalcemia, hypophosphatemia and phosphaturia to the same degree as hPTH(1-34). In kinetic studies using renal brush border membrane vesicles, the apparent Km and Vmax of phosphate transport were identical for the two peptides [hPTHrP(1-34): Km 27.6 +/- 0.8 microM, Vmax 3.78 +/- 0.04 nmol/mg protein, hPTH(1-34): Km 29.6 +/- 0.9 microM, Vmax 3.04 +/- 0.90 nmol/mg protein]. Both hPTHrP(1-34) and hPTH(1-34) at a supramaximal dose were equipotent in eliciting a 12-fold increase in cyclic adenosine 3',5'-monophosphate (cAMP) production in the kidney. These results indicate that, in addition to the similar effect of hPTHrP(1-34) and hPTH(1-34) on serum calcium levels and urinary phosphorus and nephrogenous cAMP excretion in vivo, these two peptides have similar effects of Na(+)-dependent phosphate transport in brush border membrane vesicles in vitro.

Animals↗

Growth factor gene expression in kidney of murine polycystic kidney disease.

The DBA/2FG-pcy mouse has a form of slowly progressive kidney disease that appears similar in many respects to that seen in the autosomal dominant form of human polycystic kidney disease. The aim of this study was to examine the mRNA expression of growth-related proteins in kidney obtained from DBA/2FG-pcy mice and control DBA/2 mice at 8, 16, and 30 wk of age. The mRNA levels encoding for proliferating cell nuclear antigen (PCNA), transforming growth factor (TGF)-beta, platelet-derived growth factor (PDGF)-A and PDGF-B chains, insulin-like growth factor (IGF)-I, and basic fibroblast growth factor (bFGF) were increased with the progression of cystic lesions in the kidneys of DBA/2FG-pcy mice. At 30 wk of age, mRNA levels of PCNA, TGF-beta, PDGF-A and PDGF-B chains, IGF-I, and bFGF were increased 5.4-fold, 4.8-fold, 4.4-fold, 3.8-fold, 3.7-fold, and 4.6-fold, respectively, compared with those of control DBA/2 mice. In contrast, mRNA levels for epidermal growth factor in kidney of DBA/2FG-pcy mice decreased with age as compared with those of DBA/2 mice. These results suggest that decreased epidermal growth factor mRNA expression and increased expression of PCNA, TGF-beta, PDGF-A and PDGF-B chains, IGF-I, and bFGF mRNA may contribute to the progression of cystic lesions in DBA/2FG-pcy mice.

Age Factors↗

Extracellular matrix component mRNA expression in glomeruli in experimental focal glomerulosclerosis.

This study was designed to assess how the expression of genes for components of the extracellular matrix is altered in a model of focal glomerular sclerosis. In this model, a unilateral nephrectomy combined with injections of puromycin aminonucleoside induces a much higher incidence of focal glomerular sclerosis. Rats received puromycin aminonucleoside on days 0, 27, 34, and 41 and underwent unilateral nephrectomy on day 22. Control rats received physiologic saline injections with and without unilateral nephrectomy. Rats from each group were killed on days 48, 60, and 80. The steady-state levels of glomerular mRNA encoding type IV collagen, the B1 and B2 chains of laminin, heparan sulfate proteoglycan, and type I and type III collagens were compared in both the puromycin aminonucleoside-treated and the control glomeruli. The mRNA levels encoding type IV collagen and laminin B1 and B2 were increased three-, two-, and twofold, respectively, on day 48 of focal glomerular sclerosis. These transcripts were further increased eight-, seven-, and eightfold, respectively, on day 80 compared with the control glomeruli (P < 0.01). In contrast, heparan sulfate proteoglycan mRNA levels were not increased on day 48 when the animals had marked proteinuria. However, the heparan sulfate proteoglycan mRNA levels did become elevated by day 60 and remained elevated thereafter. The expression of type I and type III collagen mRNA was increased 12- and 7-fold, respectively (P < 0.01), on day 80 in focal glomerular sclerosis rats compared with the controls. An immunofluorescence study revealed the accumulation of immunoglobulin M, C3, type IV collagen, laminin, heparan sulfate proteoglycan, and type I and type III collagens in the sclerotic area. These data indicate that changes in the mRNA levels for components of the basement membrane and interstitial collagen are associated with the development of glomerular sclerosis.

Animals↗

Increased endothelin and endothelin receptor mRNA expression in polycystic kidneys of cpk mice.

The renal mRNA levels of endothelin (ET)-1 and ET-3 and for ET receptors A and B were measured in the cystic kidneys of cpk/cpk mice at 1, 2, and 3 wk of age. At 1 wk of age, renal ET-1 mRNA was 3.2-fold greater in cystic mice than in controls and continued to increase with the progression of cyst formation to reach 10.4-fold more than controls at 3 wk. ET-3 mRNA levels did not differ between cystic and control mice. Renal ETA and ETB receptor mRNA increased gradually in cystic mice with the progression of their cysts, reaching 4.2- and 6.3-fold increases over controls, respectively, at 3 wk. Proliferating cell nuclear antigen mRNA expression was also examined, and proliferating cell nuclear antigen mRNA levels were found to be significantly increased in the kidneys of cystic mice compared with controls: 2. 1-fold at 1 wk, 4.5-fold at 2 wk, and 7.8-fold at 3 wk. The mRNA levels for transforming growth factor beta (TGF-beta) and tumor necrosis factor alpha (TNF-alpha) in the kidneys of cystic mice were also examined and were found to be increased progressively with age (TGF-beta, 2.1-fold at 1 wk, 4.2-fold at 2 wk, and 6.2-fold at 3 wk; TNF-alpha, 2.2-fold at 1 wk, 3.8-fold at 2 wk, and 5.4-fold at 3 wk).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

Alport syndrome diagnosed by immunofluorescence using a new monoclonal antibody.

A 14-year-old female with microscopic hematuria was admitted for a renal biopsy. She had a family history of renal disease without deafness. The findings of light microscopy and conventional immunofluorescence were normal. Electron microscopy showed a diffuse thinning of the glomerular basement membrane (GBM) with its mild splitting. Irregular thickening of GBM and glomerular small dense particles was not observed. Thin basement membrane syndrome was suspected from these findings. However, it was difficult to differentiate from Alport syndrome. Immunofluorescence analysis using the monoclonal antibody to the 28-kilodalton monomers of the noncollagenous domain of type IV collagen verified the diagnosis of heterozygous Alport syndrome.

Adolescent↗

mRNA expression of growth factors in glomeruli from diabetic rats.

Evaluations of glomerular mRNA levels encoding for PCNA, TNF-alpha, PDGF-A and -B chains, TGF-beta, IGF-I, bFGF, and EGF were made at 4, 12, and 24 wk after injection of STZ in Sprague-Dawley rats. The mRNA levels for PCNA, TNF-alpha, PDGF-B chain, TGF-beta, and bFGF increased with age in STZ-induced diabetic rats. At 24 wk after STZ injection, mRNA levels for PCNA, TNF-alpha, PDGF-B chain, TGF-beta, and bFGF were increased 3.8-fold, (P < 0.01), 4.2-fold (P < 0.01), 4.0-fold (P < 0.01), 5.2-fold (P < 0.001), and 3.6-fold (P < 0.01), respectively, in the glomeruli of diabetic rats when compared with control rats. In contrast, mRNA levels for IGF-I, PDGF-A chain, and EGF were not altered in glomeruli from diabetic and control rats throughout the experimental period. Insulin treatment partially ameliorated the increase in mRNA levels for PCNA, TNF-alpha, PDGF-B chain, TGF-beta, and bFGF in the glomeruli of diabetic rats. These data indicate that alterations in growth factor mRNA levels in glomeruli may be a manifestation of diabetic nephropathy, and that hyperglycemia or insulin deficiency may play a role in abnormal growth factor gene regulation.

Animals↗

Increased interleukin 6 mRNA expression by peripheral blood T cells from patients with IgA nephropathy.

We investigated interleukin 6 (IL-6) mRNA expression in peripheral blood T-cells obtained from 36 patients with IgA nephropathy (IgAN), 36 patients with other glomerulonephritides and 24 healthy age-matched controls. The majority of patients with IgAN had increased IL-6 mRNA expression by their T cells; no IL-6 mRNA was detected in T cells obtained from patients with other glomerulonephritides or normal controls. A positive correlation was noted between the IL-6 mRNA level and quantity of protein excretion in the urine, histopathological findings, and renal function. However, there was no significant correlation between IL-6 mRNA expression and the IgA-immune complex titer, serum IgA level or blood pressure. mRNA levels in T cells obtained from patients with grade III or IV renal histopathological findings were significantly higher than in those with grade I or II histopathology. In addition, mRNA levels in T cells obtained from patients with more than 1.0 g/day proteinuria were markedly higher than those with less than 1.0 g/day proteinuria. We also studied the clinical course of 11 patients with IgAN during hospitalization. The IL-6 mRNA levels in these patients decreased gradually, as did proteinuria, after treatment. These studies suggest that abnormally regulated IL-6 mRNA expression in peripheral blood T cells may be associated with disease activity in IgAN.

Adolescent↗

[Feelings of well-being and depression in relation to social activity in normal elderly people].

In order to clarify the influence of social activities on the feeling of well-being or depression in the elderly, we studied these relationships in 2 groups with different activities. Group I consisted of 26 subjects (mean age, 77.2 years) living in a retirement house and exposed to relatively few social stimuli. Group II consisted of 47 subjects (mean age, 75.6 years) who were living in their own homes and were confirmed to be socially active. The Morale Scale and the Zung Self-Rating Depression Scale (SDS) were used to evaluate feelings of well-being or depression. The morale scale in group I was significantly lower than in group II. In particular, there was a significant difference in the factor related to aging. The SDS score of group I was significantly higher than that of group II. The depressive state incidence was significantly higher in group I than in group II in all subjects. There was a highly significant correlation between the morale scale score and the SDS score. These results indicate that group I is less satisfied and more depressed than group II. We conclude that social environmental factors are extremely important for the quality of life of elderly people.

Activities of Daily Living↗