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S Takebayashi

Publications and source records attributed to S Takebayashi.

At least 91 records · Page 5Linked to original sources
PubMed1998

Two different pathways of glomerular enlargement in adults with focal and segmental glomerulosclerosis: a morphometric study.

The renal biopsy specimens obtained from 15 adults with focal and segmental glomerulosclerosis (FSGS) and 15 adults with minimal change nephrotic syndrome (MCNS) were morphometrically analyzed using light and electron microscopy. Moreover, initial biopsy specimens obtained from 10 adults who were diagnosed as MCNS and developed FSGS, based on repeat biopsy findings ('MCNS'-FSGS), were also analyzed using electron microscopy. After comparing the actual values between the groups of FSGS and MCNS, the mean glomerular volume, the capillary volume per a glomerulus, the capillary filtration surface per a glomerulus, and the capillary diameter (Cap-D) were all larger in the FSGS group than in the MCNS group. In regard to the morphological values in the 'MCNS'-FSGS group, both values of the surface density of the capillary filtering surface and the capillary diameter at the first biopsy specimens as well as those in the FSGS group were higher than those in the MCNS group. When analyzing the structural parameters, in the FSGS series, we found a high association of the percentage of obsolescent glomeruli (%SG) with the mean glomerular volume, the capillary volume per a glomerulus, the capillary filtering surface per a glomerulus and the capillary length per a glomerulus, however we failed to demonstrate the correlation between the %SG and the Cap-D. Thus, the glomerular structure in the 'MCNS'-FSGS patients, even at the first renal biopsy, resembled that in FSGS, suggesting FSGS to be a distinct entity from MCNS. These data indicate that the enlargement of the capillary volume, resulting from the widening of the capillaries, was the initial structural event for adults with FSGS, while the elongation of the capillaries appeared to reflect some compensatory process for the decrease in the functioning nephron.

Adult↗
PubMed1998

Glomerular hypertrophy as a prognostic marker in childhood IgA nephropathy.

A clinicopathological and morphometric analysis of glomerular hypertrophy (GH) was conducted using biopsies obtained from 52 selected pediatric patients with IgA nephropathy (IgAN). Of the 52 patients, consisting of 12 with chronic renal failure (CRF) and 40 without CRF, various clinical and morphometric parameters were compared to 10 controls with benign hematuria. The mean glomerular tuft size, mesangial area, and interstitial area all significantly increased in patients with poor prognosis when compared to the non-CRF-IgAN cases and the control cases. The glomerular capillary loop size was also significantly greater in CRF-IgAN than in non-CRF-IgAn patients (1.37 times) and the controls (1.55 times). The 10-year renal survival rates of patients with 'large' loop size (>1.55-fold) were significantly lower (p < 0.001) than those of patients with a smaller capillary loop size. The size of the capillary loops was directly related to the relative interstitial area (Aint) (r2 = 0.43, p < 0.001), to the degree of glomerulosclerosis (GS; r2 = 0.348, p < 0.001) and the mesangial area (r2 = 0.326, p < 0.001). Proteinuria tightly correlated with the capillary loop size (r2 = 0.374, p < 0.001). It was not unexpected that a strong relationship was detected between the serum creatinine level and Aint (r2 = 0.452, p < 0.001) and the percentage of GS (r2 = 0.342, p < 0.001). In IgAN the percentage of GS correlated significantly with Aint (r2 = 0.484, p < 0.001). GH, which was manifested by glomerular capillary loop dilatation, shows a close correlation with the interstitial expansion, degree of GS and mesangial enlargement. These data suggest that both extra- and intraglomerular hemodynamic changes followed by primary glomerular damage thus lead to capillary dilatation of the intact glomeruli as a morphological manifestation of GH and therefore such changes play a key role in the progression of IgAN.

Adolescent↗
PubMed1998

[Nonoperative management of major blunt renal lacerations with urinary extravasation: report of two cases].

Two cases of major blunt renal trauma with urinary extravasation managed by conservative treatment are presented herein. The first case: A 13-year-old girl fell from a bicycle. A computed tomographic (CT) scan showed right renal laceration with retroperitoneal hematoma. Renal arteriography showed evidence of fresh arterial bleeding without visualization of the lower pole. She was treated conservatively with superselective arterial embolization of the lower pole. She developed no urinoma with normal renal function. Renal renin and blood pressures stayed within the normal range in follow up studies. The second case: A 12-year-old boy fell from a tree and hit his right flank. A CT scan showed fragmentation of right renal cortex with retroperitoneal hematoma. He was treated conservatively as his vital signs remained stable, no active arterial bleeding was found no renal arteriography and both renal pelvis and ureters were well visualized by intra venous pyelography. Retroperitoneal hematoma was absorbed without formation of urinoma. Renal function remained within normal limits in follow up studies.

Adolescent↗
PubMed1998

[Acute renal failure in non-fulminant acute hepatitis without hepatitis A, B or C virus infection].

Here, we report a 35-year-old man with non-fulminant acute non A, non B, non C hepatitis which developed into acute renal failure. The patient was admitted to hospital with the chief complaints of general fatigue, nausea and a high-grade fever of 40 degrees C. Laboratory examination revealed severe liver dysfunction and renal insufficiency on admission: his serum glutamic oxaloacetic transaminase was 3.203 IU/ml, serum glutamic pyruvic transaminase was 3.825 IU/ml, lactic dehydrogenase was 2.840 IU/ml, blood urea nitrogen was 65 mg/dl, and creatinine was 7.6 mg/dl. Hemodialysis was conducted during the initial 19-day period after admission because anuria was manifested on admission. On the 36th day after onset, renal functions returned to normal and the patient was negative for IgM-HA antibody. HBs antigen, IgM-HBC antibody, HCV antibody, cytomegalovirus antibody, and Epstein-Barr virus antibody. However, liver biopsy for histological examination on the 44th day after onset revealed no specific findings except the healing stage of acute hepatitis. Renal biopsy on the 49th day showed the healing stage of acute tubular necrosis without any glomerular change. It has been infrequently reported that acute renal failure develops following a non-fulminant acute state without hepatitis A, B or C virus infection. It is necessary to take acute renal failure into account in the clinical course of non-fulminant non A, non B, non C hepatitis.

Acute Disease↗
PubMed1998

Diffuse thin glomerular basement membrane in association with idiopathic membranous glomerulonephritis.

Here we present a rare report of diffuse thin glomerular basement membrane (dTGBM) with idiopathic membranous glomerulonephritis (IMGN). dTGBM was found in 11 (2.04%) of 539 adult patients with IMGN. The male:female ratio was 1:1.2. Sixty patients with IMGN alone (matched for age and sex) were adjusted and analyzed as control patients. There was no significant difference in the clinical and laboratory data between the two groups except for the microhematuria, which was more frequently found in the dTGBM associated IMGN group (dTGBM + IMGN) (10/11, 91%) than in the IMGN group (19/60, 31.7%), and the difference was significant (p <0.001). However, no statistical difference was found in morphological parameters between the two groups except in the thickness of the glomerular basement membrane (GBM). In this study, using specific monoclonal antibodies against the chains of type IV collagen, no change in quality or location (in aberrant or no expression) was found in the collagenous composition of the dTGBM compared to the normal GBM. No prominent thickening or transformation of the GBM, which is characteristic for MGN, developed in the dTGBM + IMGN cases or IMGN. As a result, we could not detect any difference in the prognosis between these two groups. These findings support the view that IMGN can occur in patients with dTGBM, and the dTGBM patients may recover completely. The possible coexistence of these diseases was thus hypothesized due to the persisting microhematuria.

Adult↗
PubMed1998

[Importance of the duration from the onset of a urinary abnormality until a biopsy is performed: a multivariate analysis on the application of renal biopsy for patients with IgA nephropathy].

To clarify the importance of the duration from the onset of a urinary abnormality until a biopsy is actually performed (UA-Bx time) in making a renal prognosis, we investigated 496 patients with IgA nephropathy (male/female: 222/274, mean age: 33.0 +/- 13.7 yrs, mean follow-up period: 10.8 +/- 4.3 yrs). All patients were found to have a urinary abnormality, including both hematuria and proteinuria, at clinical onset while demonstrating a normal renal function, and showing a serum creatinine level of < or = 1.2 mg/dl or a creatinine clearance level of > or = 80 ml/min. The UA-Bx time was divided into 3 groups: < 1 yrs (S-G), 1 < or = < 3 yrs (M-G), > or = 3 yrs (L-G). The severity of glomerular damage was divided into 5 groups based on the occupational rate of segmental sclerotic glomeruli. Based on a multivariate analysis of independent prognostic factors relating to renal death, the severity of glomerular damage was the most independent factor, while the UA-Bx time showed no risk for renal death. However, based on a multivariate analysis of the UA-Bx time regarding the timing of a renal biopsy, patients in L-G, which had the most glomerular damage, showed twice the hazard ratio as those in S-G or M-G and the difference was significant. These results thus indicate that because the glomerular damage is able to progress for 3 yrs or longer after the clinical onset of renal disease, a renal biopsy should therefore be performed within 3 yrs from the clinical onset in patients demonstrating both hematuria and proteinuria when such patients are also suspected of having IgA nephropathy.

Adolescent↗
PubMed1997

Thyroid carcinoma distinctively expresses intracellular fibronectin in vivo.

Fibronectin is a multifunctional protein that plays a role in tumor invasion. We immunohistochemically examined the in vivo expression of fibronectin in thyroid carcinoma in comparison with other carcinomas, such as hepatocellular carcinoma, transitional cell carcinoma and gastric adenocarcinoma. Intracellular localization of fibronectin was found in almost all cases of thyroid carcinoma. In contrast, hepatocellular carcinoma showed a lower expression rate and the other carcinomas were all negative. These results indicate that the intracellular expression of fibronectin is not a common phenomenon in carcinoma, but rather is distinctive for thyroid carcinoma.

Adenocarcinoma↗
PubMed1997

Acute confusional migraine and migrainous infarction in childhood.

We report two children with acute confusional migraine (ACM) and another with migrainous infarction (MI), aged 7-12 years. There was a family history of migraine in all patients. The patients, who were all right-handed, all manifested sudden onset of consciousness disturbance and other neurological deficits as the first aura in their life. The symptoms in all cases almost completely resolved spontaneously within 24 h, but transient occipital slowing on EEG with laterality corresponding to the side of migrainous origin lasted more than 24 h. In the cases of ACM in the critical phase, although MRI and MR angiography showed no abnormal findings, IMP-SPECT performed within 48 h of migraine attacks revealed a regional change in cerebral blood flow, which is one particular case demonstrated hypoperfusion in the left posterior cerebral artery (PCA) territory. Therefore, although ACM was diagnosed clinically by exclusion, SPECT was thought helpful for the diagnosis of ACM. We speculated that transient hypoperfusion affecting the dominant-sided PCA territory involving the medial temporal structures was responsible for the confusion with amnesia in ACM, in contrast to the lack of confusion or amnesia in the case of MI showing cystic encephalomalacia in the right thalamic and hippocampal regions.

Acute Disease↗
PubMed1997

Mechanism of action of gemfibrozil on HDL metabolism and atherosclerosis in WHHL rabbits.

We investigated the mechanism of action of gemfibrozil on high-density lipoproteins (HDL) and apolipoprotein (apo) A-I metabolism and atherogenesis in homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits, an animal model of familial hypercholesterolemia and HDL deficiency. Two-month-old WHHL rabbits were fed either a normal control diet or a diet containing 0.5% gemfibrozil for 12 months. In vivo apo A-I kinetics, the fractional rate of cholesterol esterification in HDL (FER[HDL]), which reflects the reactivity of HDL to lecithin:cholesterol acyltransferase, and a morphometrical analysis of atherosclerotic lesions in the descending thoracic aorta, were examined. At 12 months, the mean levels of serum total cholesterol, LDL cholesterol (LDL-C), and HDL cholesterol (HDL-C) in both groups had decreased to approximately 53%, 57%, and 87% of the initial levels (at 0 month), respectively, which is characteristic of homozygous WHHL rabbits of the physiologic influence of aging, and no differences in the levels of serum LDL-C, HDL-C, and triglycerides were found between the two groups. Rabbits treated with gemfibrozil exhibited a decreased FER(HDL) (38% of the controls, P = 0.039). Gemfibrozil induced a significant increase in the total mass of apo A-I (1.7-fold, P < 0.05) and in the rate of apo A-I synthesis (1.6-fold, P < 0.05). The atherosclerotic intimal area was positively correlated with serum LDL-C (P = 0.02) in both groups, but gemfibrozil did not affect the atherosclerotic intimal area. These results indicate that 12 months of treatment with gemfibrozil did not protect against atherosclerosis despite a significant increase in apo A-I synthesis and enhanced HDL function through FER(HDL). It is possible that both the qualitative and quantitative improvement in HDL by gemfibrozil cannot overcome the massive and long-term exposure of the vascular wall to LDL in these animals.

Animals↗
PubMed1997

Relationship between left ventricular diastolic function at rest and exercise capacity in patients who have suffered a previous myocardial infarction.

To assess whether left ventricular (LV) diastolic function is a determinant of exercise capacity in patients who have suffered a previous myocardial infarction (MI), we investigated the relationship between maximum exercise duration and resting LV diastolic function in 65 MI patients. Each patient underwent both a symptom-limited exercise test and LV biplane angiography with simultaneous high-fidelity pressure measurements. LV relaxation was assessed by the time constants (T1/e and T1/2) of isovolumic pressure decay, and LV diastolic distensibility was assessed by the LV end-diastolic volume (V) index-pressure (P) ratio. The time constants of relaxation did not correlate with maximum exercise capacity (r = -0.19 for T1/e, NS; r = - 0.17 for T1/2, NS). LV diastolic distensibility also did not correlate with exercise capacity (r = - 0.08, NS). These results suggest that the resting LV diastolic dysfunction is unlikely to be the principal cause of exercise intolerance in MI patients without congestive heart failure.

Adult↗
PubMed1997

[Study of trough type audiogram of sudden hearing loss].

We investigated 974 patients with sudden sensorineural hearing loss who consulted the otolaryngological service of Hamamatsu University Hospital and four affiliated hospitals from 1984 to 1992. Among them, we selected 569 new cases showing a pure tone average of 31 dB or more at 250 Hz, 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz on the affected side in the initial audiometry performed within 14 days after the onset of sudden sensorineural hearing loss. The 569 patients consisted of 13 with acoustic neuromas (SHLANs), 493 with idiopathic sudden sensorineural hearing loss (ISHLs) and 63 others. Ten of the 13 SHLANs and 40 of the 493 ISHLs showed the trough type audiogram on the initial examination. We defined the 10 cases as the Trough AN group and the 40 as the Trough ISHL group. Statistical analysis of the difference in pure tone averages at 5 frequencies between the 2 groups demonstrated that the mean hearing losses at 125, 250 and 500 Hz of Trough AN were significantly less than those of Trough ISHL. This study demonstrates that the trough type audiogram, especially a slight low tone loss, shown in patients with sudden sensorineural hearing loss was a significant finding suggesting the presence of acoustic neuroma.

Adult↗
PubMed1997

Chronic exertional compartment syndrome in lower legs: localization and follow-up with thallium-201 SPECT imaging.

UNLABELLED: The purpose of this study was to ascertain whether 201Tl SPECT imaging of the leg is useful in precise localization of the ischemic compartment involved in chronic exertional compartment syndrome (CECS). METHODS: Imaging and quantitative analyses of postexercise 201Tl SPECT leg examinations were retrospectively performed in nine patients with clinically diagnosed CECS and eight control subjects. Imaging and quantitative criteria for the ischemic compartment were decreased 201Tl perfusion less than the lower limits of normal, which were defined as 2 s.d. below the mean percentage uptake of the control subjects. The SPECT imaging results were compared with those of quantitative analysis, postoperative SPECT images and clinical diagnoses. RESULTS: Postexercise normal legs had nonuniform 201Tl distribution in both legs and in the four compartments. Lower limits of normal mean percentage 201Tl uptake were about 60% for the anterior compartment and about 50% for the other three compartments. Redistribution was observed in 67% of normal compartments in the control subjects. The SPECT images demonstrated 16 ischemic compartments in eight of the nine patients. The SPECT results were consistent with those of quantitative analysis. There were discrepancies between the clinical and SPECT diagnoses in six legs (33% of the 18 legs) of five patients. Postoperative SPECT demonstrated 201Tl perfusion was improved in all involved compartments for that fasciotomy was performed. CONCLUSION: Thallium-201 SPECT imaging of the legs can easily provide precise localization of the ischemic compartment, which is demonstrated as decreased 201Tl distribution on the stress image. This technique is promising for the screening and follow-up of CECS.

Adult↗
PubMed1997

Lobular form idiopathic glomerulonephritis with massive subendothelial and paramesangial immune deposits, a three-year follow-up case.

We report a patient with unusual glomerulonephritis. A 24-year-old Japanese female was hospitalized in October 1995 because of nephrotic syndrome. Lobular form glomerulonephritis with mesangial proliferation associated with massive wide-spread accumulation of slightly eosinophilic, periodic acid Schiff-positive amorphous materials in the luminal side of the capillary walls and paramesangial area was observed in the renal biopsy specimen. Immunofluorescent study revealed massive strong staining for IgM and C4 along the capillary walls and in the mesangium. Deposits of IgA, IgG, C3 and fibrinogen were also observed. Electron microscopy showed normal thickness of the capillary basement membrane and a large amount of subendothelial and paramesangial electron dense, finely granular deposits without fibrils or tubular structures. There were no clinical or laboratory findings of systemic diseases, such as systemic lupus erythematosus and cryoglobulinemia. Therefore, we believed that this case involved an unusual idiopathic glomerular disease with massive subendothelial and paramesangial immune deposits. Glomerulonephritis in this patient appeared to be resistant to treatment with corticosteroids and that this glomerulopathy may be a progressive disease as shown during the 3-year observation. Furthermore, our patient had idiopathic hyperprolactinemia and subclinical hypothyroidism. However, the relationship between glomerulonephritis and endocrinopathy in our patient is unknown.

Adult↗
PubMed1997

Thymidine phosphorylase activity in human bladder cancer: difference between superficial and invasive cancer.

The activity of thymidine phosphorylase (TdR-Pase), which is identical to platelet-derived endothelial cell growth factor (a potent angiogenic factor), was analyzed in primary human bladder cancer tissues. TdR-Pase activity in tissues was determined from the conversion rate of 5'-deoxy-5-fluorouridine to 5-fluorouracil. The mean activity in 37 bladder cancers and in 8 samples of normal bladder epithelial tissue was 108.5 and 19.2 microgram 5-fluorouracil/mg protein/h, respectively, showing a statistically significant difference. Among the cancer tissues, differences in activity were seen according to the stage and grade of tumors. Low-grade (grade 1) tumors had significantly lower activities than high-grade tumors, and high-grade invasive tumors showed significantly higher activities than low-grade superficial tumors. These results demonstrate that a high TdR-Pase activity in bladder cancer is associated with the tumor characteristics of invasion and malignant potential. Our conclusions support the hypothesis that angiogenesis that is mediated by this molecule may be involved in the development of invasive human bladder cancer, as suggested by T. O'Brien et al. (Cancer Res., 55: 510-513, 1995), and also suggest that TdR-Pase is a potential therapeutic target in human bladder cancer.

Epithelial Cells↗
PubMed1996

The influence of oxygen free radical scavengers on the reduction of membrane-bound Na(+)-K(+)-ATPase activity induced by ischemia/reperfusion injury in the canine kidney.

The present study was designed to determine whether the administration of free radical scavengers, superoxide dismutase (SOD), catalase or dimethylsulfoxide (DMSO) is able to ameliorate ischemia/reperfusion injury in the canine kidney and also ascertain whether or not a relationship exists between oxygen free radicals and membrane-bound Na(+)-K(+)-ATPase activity. In 23 dogs, the vascular pedicle of the left kidney was clamped for 75 min at room temperature. The experimental animals received free radical scavengers for 30 min starting at 2 min prior to reperfusion. Renal tissue specimens were enzyme-histochemically examined regarding the activity of membrane-bound Na(+)-K(+)-ATPase, and a marked reduction just before reperfusion was revealed. The SOD- and the DMSO-treated groups showed a marked recovery of the membrane-bound Na(+)-K(+)-ATPase activity; however, the untreated and the catalase-treated groups still demonstrated a marked reduction 1 day after reperfusion. At the same time, widespread acute tubular necrosis in the cortex was observed in the untreated and catalase groups in comparison with the SOD and the DMSO groups. In addition, the SOD and the DMSO groups significantly preserved better renal function. Based on these findings, it was thus concluded that free radical scavengers ameliorate the recovery of depressed membrane-bound Na(+)-K(+)-ATPase activity and ischemia/reperfusion injury in the canine kidney.

Animals↗