PubMed Health⌕ Search

Biomedical subjects

Y Yaguchi

Publications and source records attributed to Y Yaguchi.

35 records · Page 2Linked to original sources
PubMed1993

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↗
PubMed1993

[Serum superoxide dismutase (SOD) activity in patients with renal disease by a spintrap method using electron spin resonance (ESR)].

Superoxide dismutase (SOD) activity in serum samples of patients with chronic glomerulonephritis (CGN) and chronic renal failure (CRF) was measured by a spin trap method using electron spin resonance (ESR). Twenty-three patients with CGN, 10 patients with CRF and 10 healthy adults were examined. Among 23 patients with CGN, there were 12 patients with IgA nephropathy and one patient with membranous nephropathy diagnosed by immunofluorescence of renal biopsy specimens. Other CGN patients were diagnosed by its clinical criteria. The serum activity of SOD in patients with CGN or CRF was significantly higher than those in healthy adults (p < 0.05). The serum SOD activity in patients with CRF was also higher than those in patients with CGN (p < 0.05). Marked high levels of serum SOD activity were observed histologically in the advanced stage of IgA nephropathy. These results suggest an increase in serum SOD activity may reflect renal injuries in patients with CGN and CRF.

Chronic Disease↗
PubMed1992

Oxidative metabolism of polymorphonuclear leukocytes (PMN) in patients with IgA nephropathy.

The production of hydrogen peroxide (H2O2) by neutrophilic polymorphonuclear leukocytes (PMN) after stimulation and the infiltration of PMN in glomeruli were determined in 20 patients with primary IgA nephropathy. The H2O2 production of PMN after the stimulation was measured with a spectrophotometer using horseradish peroxidase as substrate. The results were as follows: 1) when PMN were pretreated with cytochalasin B, H2O2 production after stimulation with heat-aggregated IgG (IgG) or serum-treated zymosan (STZ) was significantly higher in patients with IgA nephropathy than in controls, and 2) there was an increased amount of PMN localized in glomeruli in patients with IgA nephropathy using immunofluorescence of monoclonal anti-PMN antibody. It appeared that the increased renal infiltration of PMN which have a high potential for production of reactive oxygen species might induce the glomerular injuries in patients with IgA nephropathy.

Adult↗
PubMed1992

Correlation between reduction of polymorphonuclear leucocytes in glomeruli injected with a newly developed monoclonal antineutrophil antibody and proteinuria in Masugi nephritis.

The effects of the reduction of neutrophils in glomeruli on the improvement of proteinuria and glomerular injuries were determined in the first (heterologous) phase of Masugi (nephrotoxic) nephritis. Male (6-week-old) WKA/Hkm rats were initially injected with 2.0 ml of a newly developed monoclonal antineutrophil antibody and then injected with 1.0 ml of nephrotoxins. This monoclonal anti-neutrophil antibody was found to have selectively reduced the number of neutrophils in the glomerular capillary lumen in cases of Masugi nephritis by light microscopy. Malondialdehyde (MDA) levels or superoxide dismutase (SOD) activities in renal tissues of such rats were also examined. However, there were no significant differences in the levels of proteinuria and the number of glomerular cells containing resident cells and infiltrated mononuclear cells in the first phase of Masugi nephritis with or without pretreatment with antineutrophil antibody. No significant differences were observed in the levels of MDA or SOD activities in renal tissues of Masugi nephritis with or without pretreatment with such an antibody either. It appeared that infiltration of neutrophils in the glomeruli might not be related to proteinuria and glomerular injuries in the first phase of Masugi nephritis. It was postulated that the massive proteinuria in the first phase of Masugi nephritis might be correlated with the activities of reactive oxygen species induced by the glomerular cells, i.e. glomerular resident cells and infiltrated mononuclear cells.

Animals↗
PubMed1992

[Protective effects of the bark of Myrica rubra Sieb. et Zucc. on experimental liver injuries].

The methanol extract from the bark of Myrica rubra SIEB. et ZUCC. showed protective effects on liver injuries induced by carbon tetrachloride (CCl4) and alpha-naphthylisothiocyanate (ANIT) in rats. In this study, the fractions and some compounds from the bark of M. rubra were investigated for the protection against CCl4 inducing liver injuries in rats. The active principles for the protection were recognized in two fractions (M-3 and M-5 Fr. 1) obtained from the methanol extract, and one of the active principles in the fraction (M-3) was found to be myricanol 5-O-beta-D-(6'-O-galloyl)-glucopyranoside. In addition, these fractions protecting liver injuries induced by CCl4 showed significant protective effects against cholestasis induced by ANIT.

Animals↗
PubMed1991

Altered steady-state levels of mRNA coding for extracellular matrices in renal tissues of ddY mice, an animal model for IgA nephropathy.

Correlations between the steady-state mRNA levels of extracellular matrices using specific cDNA probes for the alpha 1 chain of type IV collagen (alpha 1 (IV) chain); laminin A, B1, and B2 chains; and heparan sulfate proteoglycan (HSPG); and glomerular injuries in ddY mice were evaluated. Eight-, sixteen- and forty-week-old ddY mice were used in this study. ICR mice of the same age served as control. Extracted total RNA of pooled kidneys was fixed on a filter and then hybridized with the cDNA probes. Renal cryostat sections were incubated with rabbit anti-mouse type IV collagen, laminin, and HSPG antisera and then stained with FITC-labeled goat anti-rabbit IgG antiserum. The sections were also stained with FITC-labeled goat anti-mouse IgA, IgM, IgG, and C3 antisera. In light microscopy, the average number of glomerular cells was calculated at each age. Increased expression of extracellular matrices genes for the alpha 1(IV) chain; laminin A, B1, and B2 chains; and HSPG was found in renal tissues of ddY mice. Staining of type IV collagen, laminin, and HSPG was observed in renal tissues of ddY mice at each age. Increased proteinuria in 40-week-old ddY mice might be related to the decrease in glomerular basement membrane HSPG which acts as the anionic sites in such areas. Marked proliferation and or expansion of glomerular cells and mesangial matrices were observed in 40 week-old-ddY mice. The intensity of IgA and C3 deposits in the glomeruli was parallel to the levels of mRNA for such components.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Computer imaging analysis of the correlation between intensities of glomerular immune-deposits and histopathology in patients with IgA nephropathy.

The relationship between the intensities of IgA, C3c, and C9 deposition in renal glomeruli and the severity of histopathologic injuries in patients with IgA nephropathy was examined using Microscope-Photometer 01K and a computer. Percentages of glomerular adhesion to Bowman's capsules, crescent formation, and glomerular sclerosis were calculated in the renal specimens. There was a significant correlation between the intensity of each C3c and C9 deposition in glomeruli and the degree of glomerular adhesion to Bowman's capsules and crescent formation in patients with IgA nephropathy. There was no significant correlation between the intensity of C3c or C9 deposition in glomeruli and the degree of glomerular sclerosis. No relationship was found between the intensity of IgA deposition in glomeruli and the degree of histopathologic injuries. The patients with negative or trace amounts of glomerular C3c deposits showed less severe glomerular injuries. Thus, the intensity of C3c and C9 deposition in glomeruli appears to be one of the critical factors responsible for the active progression of glomerular inflammatory process in patients with IgA nephropathy.

Complement C3c↗
PubMed1991

Glomerular nonenzymatic glycosylation and lipid peroxide are increased in the early phase of streptozotocin-induced diabetic rats prior to major histopathologic alterations.

Levels of glomerular nonenzymatic glycosylation and lipid peroxide in streptozotocin (STZ)-induced diabetic rats were examined. Isolation of glomeruli was performed using a sieving technique. The levels of nonenzymatic glycosylation in the glomeruli of these rats were measured by the thiobarbituric acid (TBA) method. Measurement of lipid peroxide, i.e., malondialdehyde (MDA), levels in the renal cortex, medulla and isolated glomeruli was performed by the TBA test. Light-microscopic and immunofluorescent examinations were also performed. An increase in nonenzymatic glycosylation in the glomeruli was observed in the early phase, i.e., after 4 and 12 weeks, in STZ-induced diabetic rats. The levels of MDA in the renal cortex of 12-week-old STZ-induced diabetic rats were also significantly increased compared with those of control rats at the same age. Levels of MDA in the glomeruli of 12-week-old STZ-induced diabetic rats were slightly increased compared with those of control rats, but there was no statistical significance. In immunofluorescence, IgG or IgM was deposited in the glomerular mesangial areas and capillary walls in 12-week-old diabetic rats. However, there was no significant change in renal tissues after 4 and 12 weeks in STZ-induced diabetic rats. It was concluded that glomerular nonenzymatic glycosylation and lipid peroxide were already increased in the early phase of STZ-induced diabetic rats prior to the appearance of marked histologic alterations.

Animals↗
PubMed1989

[Comparative studies of clinicopathological findings in patients with adult and juvenile onset of IgA nephropathy].

Comparative studies of clinicopathological findings were carried out in 89 patients with adult and juvenile onset of IgA nephropathy. Among 89 patients with IgA nephropathy, there were 42 patients with juvenile onset, i.e less than 19 years old, and 47 patients with adult onset, i.e. more than 35 years old. Clinical activities of both groups were examined as follows; urinary protein, mean blood pressure renal function (PSP 15 min, Ccr) and serum IgA (s-IgA). The histology of renal tissues was also examined by light microscopy and immunofluorescence in both groups. The levels of mean blood pressure or s-IgA in patients with adult onset group were significantly higher than those in patients with juvenile onset group (p less than 0.001). The levels of Ccr in patients with adult onset group were markedly decreased. The patients with more than 1.0g/day of proteinuria and more than 110 mmHg of mean blood pressure showed severe proliferative glomerular injuries by light microscopy. It is suggested that the patients with adult onset of IgA nephropathy show severe progressive and/or exacerbating factors during the clinical course.

Adolescent↗
PubMedDate not supplied

Plasma lidocaine, monoethylglycinexylidide, and glycinexylidide concentrations after epidural administration in geriatric patients.

BACKGROUND AND OBJECTIVES: The purpose of this study was to evaluate the effect of age on the pharmacokinetics of lidocaine after epidural administration. METHODS: Two percent lidocaine with epinephrine (5 microg/mL) was administered in two different age groups: an adult group (age 42 +/- 6 years, n = 10) and an elderly group (age 77 +/- 4 years, n = 10). Concentrations of lidocaine and its active metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), were measured in plasma samples obtained after 15, 30, 45, 60, 90, 120, 150, and 180 minutes of administration using high-performance liquid chromatography with ultraviolet detection. RESULTS: No significant differences in plasma concentrations of lidocaine and its metabolites were observed between the two groups during the 3 hours of study. However, the elderly group showed significantly longer mean residence times (MRTs) and lower plasma clearance of lidocaine during the period compared with the adult group (P < .05). Plasma concentration ratios of MEGX/lidocaine were significantly lower in the elderly group after 2 hours of lidocaine administration (P < .05). CONCLUSIONS: The increase in plasma lidocaine concentration after epidural anesthesia in elderly patients was not as high as anticipated. However, the elderly patients showed longer MRTs, lower clearance, and lower ratios of MEGX/lidocaine than did the adult (middle-age) patients.

Adult↗