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Y Kondo

Publications and source records attributed to Y Kondo.

At least 397 records · Page 22Linked to original sources
PubMed1995

Cyclosporin A prevents ischemia-induced reduction of muscarinic acetylcholine receptors with suppression of microglial activation in gerbil hippocampus.

We previously reported the late onset reduction of muscarinic acetylcholine receptors (LORMAR) which begins 7 days after a 5-min period of experimentally induced forebrain ischemia in the gerbil hippocampus. This study demonstrated that post-ischemic administration of cyclosporin A (CsA) reduced LORMAR 10 days after 5 min of forebrain ischemia in the gerbil hippocampus, suggesting that immunosuppression by CsA may reduce damage to the cholinergic system after ischemia. Microglia positive for HLA-DR class II antigen which presented in the hippocampal CA1 area, the region most vulnerable to ischemia, were also reduced by CsA. CsA may suppress microglial activation especially with regard to the antigen-presenting function, and LORMAR may be attenuated by this modulation of microglial function.

Animals↗
PubMed1995

Effects of single cyclosporin A pretreatment on pentylenetetrazol-induced convulsion and on TRE-binding activity in the rat brain.

Using electrophoretic mobility-shift assay (EMSA), we examined changes in DNA-binding activities of transcriptional factor-activated protein-1 (AP-1), which is a Fos-Jun protein complex, onto its responsive element TRE in the hippocampus and amygdaloid nucleus of rats stimulated with pentylenetetrazol (PTZ) injection, and also investigated the effects of a single administration of the immunosuppressant cyclosporin A (CsA). In EMSA with nuclear extracts from the rat brain, the TRE-binding activity of AP-1 in the hippocampus and amygdaloid nucleus markedly increased 2 h after the PTZ injection (75 mg/kg, i.p.). These PTZ-induced increases of the TRE-binding protein in these regions were completely suppressed, by pretreatment with CsA (5 mg/kg, s.c.) 1 h before the PTZ injection. In addition, the administration of CsA significantly ameliorated PTZ-induced convulsion. This therapeutic effect of single CsA pretreatment may be based, in part, on the effects on the TRE-binding activity of AP-1 in the brain. Since single pretreatment of CsA in the present study had no effect on the PTZ-induced induction of c-fos mRNA, c-jun mRNA, Fos protein nor Jun protein, the inhibitory effects of single CsA administration on PTZ-induced TRE-binding activity in the brain may be related to the effects of CsA on AP-1 itself. These results suggest that an immune response via activation of transcriptional factor in the brain tissue is involved in the convulsion.

Amygdala↗
PubMed1995

The possible involvement of the nonstrial pathway of the amygdala in neural control of sexual behavior in male rats.

The effect of medial amygdala lesions on male sexual behavior in male rats with stria terminalis cut was examined. First, castrated male rats received bilateral transections of the stria terminals (STC) or sham cut (SC). Most STC males showed no ejaculation, but displayed mount and intromission, although the frequencies were not high compared to those of males with SC. Next, bilateral lesions of the medial amygdala (MAL) or sham lesion (SL) were performed in males with STC or SC. The MAL caused severe loss of all aspects of copulatory behavior in males with STC as well as in males with SC. The suppressive effect of the MAL on copulatory activity was stronger than that of the STC. These results indicate that a neural pathway other than the stria terminalis is involved in the regulation of male sexual behavior by the amydgala in male rats.

Amygdala↗
PubMed1995

Nucleolar organizer regions in hepatocellular carcinoma related to the cell cycle, cell proliferation and histologic grade.

In order to clarify factors which relate to AgNOR in hepatocellular carcinoma (HCC), AgNOR numbers and the expression of Ki-67 using MIB-1 antibody have been studied in paraffin-embedded specimens of 20 HCCs by means of a double staining method. We found that in individual cases the AgNOR number of MIB-1-positive cells was significantly higher than that of MIB-1-negative cells (p < 0.001). In addition, a significant correlation was seen between MIB-1 labelling index and the total mean AgNOR number (t-AgNOR) (r = 0.882, p < 0.001). The value of t-AgNORs was significantly higher in histologically less differentiated HCC (p < 0.005). The mean AgNOR number of MIB-1-negative cells (n-AgNOR) was also significantly higher in histologically less differentiated HCC (p < 0.04). By contrast, the mean AgNOR number of MIB-1-positive cells (p-AgNOR) did not significantly correlate with histologic grades (p = 0.265). However, the number of t-AgNORs was not significantly different between diploid and aneuploid tumours. In HCCs, it appears that AgNOR numbers were variably influenced by proliferative activities of tumour cells, phases of cell cycle and cell differentiation.

Antigens, Neoplasm↗
PubMed1995

Tumour angiogenesis and tumour cell proliferation as prognostic indicators in gastric carcinoma.

Tumour growth depends on neovascularisation and tumour cell proliferation. Factor VIII-related antigen (F-VIII RA) localises to vascular endothelium. Expression of proliferating cell nuclear antigen (PCNA) is correlated with cell proliferation. We investigated the correlation between the expression of these antigens and prognosis in gastric carcinoma. A total of 108 specimens resected from patients with gastric carcinoma were investigated by staining with monoclonal antibodies against F-VIII RA and PCNA. Microvessel count (MVC; the mean number of microvessels in the five areas of highest vascular density at 200 x magnification) and PCNA labelling index (PCNA LI; percentage of positive cells in more than 500 tumour cells) were determined. The results showed that prognosis was significantly worse in patients who had a tumour with a high MVC (16 or greater) or a high PCNA LI (42% or greater) than in those patients who had a tumour with a low MVC (less than 16) or a low PCNA LI (less than 42%). Furthermore, MVC was significantly associated with the risk of hepatic recurrence. In conclusion, both MVC and PCNA LI may be good prognostic indicators in patients with gastric carcinoma.

Adult↗
PubMed1995

Regional differences in late-onset iron deposition, ferritin, transferrin, astrocyte proliferation, and microglial activation after transient forebrain ischemia in rat brain.

With use of iron histochemistry and immunohistochemistry, regional changes in the appearance of iron, ferritin, transferrin, glial fibrillary acidic protein-positive astrocytes, and activated microglia were examined from 1 to 24 weeks after transient forebrain ischemia (four-vessel occlusion model) in rat brain. Expression of the C3bi receptor and the major histocompatibility complex class II antigen was used to identify microglia. Neuronal death was confirmed by hematoxylin-eosin staining only in pyramidal cells of the hippocampal CA1 region, which is known as the area most vulnerable to ischemia. Perls' reaction with 3,3'-diaminobenzidine intensification revealed iron deposits in the CA1 region after week 4, which gradually increased and formed clusters by week 24. Iron also deposited in layers III-V of the parietal cortex after week 8 and gradually built up as granular deposits in the cytoplasm of pyramidal cells in frontocortical layer V. An increasing astroglial reaction and the appearance of ferritin-immunopositive microglia paralleled the iron accumulation in the hippocampal CA1 region, indicating that iron deposition was probably produced in the process of gliosis. Neither neuronal death nor atrophy was found in the cerebral cortex. Nevertheless, an astroglial and ferritin-immunopositive microglial reaction became evident at week 8 in the parietal cortex. On the other hand, the granular iron deposition in the pyramidal neurons of frontocortical layer V was not accompanied by any glial reaction in the chronic stage of ischemia. Three different types of iron deposition in the chronic phase after transient forebrain ischemia were shown in this study. In view of the neuronal damage caused by iron-catalyzed free radical formation, the late-onset iron deposition may be relevant to the pathogenesis of the chronic brain dysfunction seen at a late stage after cerebral ischemia.

Animals↗
PubMed1995

Characterization of Na+ transport across the cell membranes of the ascending thin limb of Henle's loop.

In the ascending thin limb of Henle's loop (ATL), intracellular Na+ is extruded by Na+/K+ ATPase in the basolateral membrane. To further characterize Na+ transport across the cell membranes of the ATL, the intracellular sodium concentration ([Na+]i) was monitored using a sodium-sensitive fluorescent probe, SBFI, in the in vitro microperfused hamster ATL. Basal [Na+]i was 19.0 +/- 1.2 mM (N = 24). Removal and replacement of luminal Na+ did not change [Na+]i in the presence of Na+ in the bathing fluid. In contrast, luminal Na+ removal reduced [Na+]i from 11.6 +/- 0.9 to 6.3 +/- 0.8 mM in the absence of peritubular Na+ (P < 0.0005, N = 21). Replacement of luminal Na+ increased [Na+]i to 12.6 +/- 0.9 mM. In the absence of Na+ in the bath, the addition of 1 microM benzamil, 0.1 mM 5-(N,N-dimethyl)-amiloride (DMA), 0.1 mM furosemide, or 0.1 mM trichlormethiazide to the lumen did not change [Na+]i or the rate of change in [Na+]i/dt) after removal and replacement of luminal Na+. Decreases in luminal pH in a Hepes-buffered solution and luminal HCO3- did not affect [Na+]i. In the absence of peritubular Na+, DMA in the bathing fluid decreased [Na+]i from 11.4 +/- 1.3 to 6.4 +/- 1.2 mM (P < 0.01, N = 5) and completely inhibited the changes in [Na+]i after removal and replacement of luminal Na+. Removal of peritubular Na+ reduced [Na+]i from 18.8 +/- 1.2 to 11.3 +/- 0.7 mM (P < 0.0001, N = 23). Addition of DMA in the bathing fluid reduced [Na+]i and inhibited the changes in [Na+]i after removal and replacement of peritubular Na+.(ABSTRACT TRUNCATED AT 250 WORDS)

Amiloride↗
PubMed1995

Interaction of calponin with phospholipids.

The interaction between chicken gizzard calponin and phospholipids was examined by sedimentation assay and affinity chromatography. Calponin was sedimented with phosphatidylserine (PS) and phosphatidylinositol (PI) vesicles but not with phosphatidylcholine (PC) vesicles. The apparent Kd values of calponin to PS and PI were calculated to be 1.3 x 10(6) and 1.5 x 10(6) M-1, respectively. Domain mapping with chymotryptic digestion showed that the phospholipid-binding site resided within the N-terminal 22-kDa fragment, in which the bindings of actin, calmodulin, S100, and tropomyosin also occur. The amount of calponin bound to PS and PI vesicles decreased with increasing ionic strength or Ca2+ concentrations. The presence of MgCl2 was needed for the calponin-PS vesicle interaction. Calponin-binding proteins including actin, calmodulin, and S100 inhibited calponin binding to the phospholipid vesicles in a concentration-dependent manner, while tropomyosin had little effect on the binding. The inhibitory effects of calmodulin and S100 were found only in the presence of CaCl2. Neither caldesmon nor SM22 affected the binding.

Actins↗
PubMed1995

Morphology of a cytochrome c-adsorbed stearic acid monolayer on Brewster angle microscopy.

The morphologies of stearic acid and cytochrome c (cyt.c)-adsorbed stearic acid monolayers were investigated by Brewster angle microscopy (BAM) with various molecular areas of stearic acid. With an area of more than 0.38 nm2/molecule, many blight island domains and some bright circles were observed in the BAM image of the stearic acid monolayer. The blight site part became to occupy all the surface with compression, and then became more closely packed with an area of 0.22 nm2/molecule. On the other hand, a different BAM image was obtained for the cyt.c-adsorbed stearic acid monolayer, as follows: (i) a striped pattern was only observed in the presence of cyt.c; (ii) the number of bright circles in the presence of cyt.c was less than that in its absence. Furthermore, when a uniform BAM image was observed for the stearic acid monolayer with cyt.c, the intensity of the absorbance at 409 nm of cyt.c was the highest. By calculating the amount of cyt.c adsorbed on a stearic acid monolayer from the absorbance value, it was shown that cyt.c was most closely packed when an uniform BAM image was observed. These results suggest that the use of BAM and visible absorption spectroscopy together is useful for studying the morphology of a monolayer.

Adsorption↗
PubMed1995

Age-related, different clinicopathologic features of hepatocellular carcinoma patients.

OBJECTIVE: The authors attempted to clarify the clinicopathologic differences of hepatocellular carcinoma (HCC) patients, according to age distribution, and to investigate whether these differences contribute a certain hepatocarcinogenesis. SUMMARY BACKGROUND DATA: Hepatitis-associated viruses causing HCC have been investigated, and the infection of the viruses and etiologically, the peak age of the disease vary according to geographic barriers. However, a correlation between clinicopathologic differences and the age distribution of the patients is not well understood. METHODS: The authors reviewed their institutional experience from 1978 to 1990 in treating 428 patients with HCC. The carrier rate for hepatitis B surface antigen (HBsAg), the frequency of occurrence of high serum alpha-fetoprotein (AFP) of 2000 ng/mL, the degree of liver damage represented by the retention rate of indocyanine green dye at 15 minutes (ICGR15), and the incidence of accompanying liver cirrhosis were investigated and compared in each decade of age. RESULTS: The HBsAg carrier rate and the frequency of high serum AFP values were significantly prominent in the younger patients (20-49 yrs). The degree of liver damage and the incidence of liver cirrhosis were prominent in the elderly patients (older than 70 yrs) or the middle-aged patients (50-69 yrs); however, these four values in the middle-aged patients were intermediate with respect to those observed in the other two age groups. In addition, there was a positive correlation between the HBsAg carrier rate and the frequency of high serum AFP values or between the degree of liver damage represented by ICGR15 and the incidence of liver cirrhosis, showing that the former correlation was inversely related to the latter. CONCLUSIONS: The authors' study indicates that there are age-related differences of clinicopathologic features in HCC patients, suggesting that there are different steps or mechanisms of hepatocarcinogenesis according to the patient's age-distribution.

Adolescent↗
PubMed1995

Intratumoral injection of an adriamycin immunoconjugate against human pancreatic cancer xenografts.

We have evaluated the effect of an adriamycin conjugate of monoclonal antibody Nd2 (ADM-Nd2) on the growth rate of SW1990 xenografts grown subcutaneously in athymic nude mice. Intravenous or intraperitoneal administration of radiolabeled Nd2 resulted in a maximum tumor accumulation of approximately 45% of the initial dose/g of tumor 3-7 days after administration. However, administration into the tumor produced retention of 1200%ID/g 1 day after, with 50% of this high value remaining even at 7 days after administration. In contrast, intratumoral administration of a non-specific immunoglobulin showed a lower initial retention and rapid loss of label. Both intravenously and intratumorally administered ADM-Nd2 reduced the growth rate of SW1990 xenografts. While a single intravenous administration arrested growth for about two weeks, a single intratumoral injection prevented any increase in tumor size even 45 days after administration. Xenografts treated with ADM-Nd2 showed degenerative changes at the histological level. Neither Nd2 alone nor Adriamycin alone inhibited growth when administered at the same dose as the conjugate.

Animals↗
PubMed1995

Growth patterns and interstitial invasion of small hepatocellular carcinoma.

Twenty-five cases of small hepatocellular carcinoma (HCC; diameter < or = 30 mm) were evaluated for overall morphologic features and growth patterns. The tumors often showed a well-differentiated, normotrabecular histologic pattern and insidious interstitial invasion, which resembled benign hepatocytes scattered in connective tissues. As the tumor grew, a less-differentiated tumor area became predominant. Portal tracts included in small HCC nodules were quantitatively assessed, revealing that they progressively reduced in number with tumor growth. The tumor margin was often reported to be unclear. The present results indicate that the histologic grade of tumor differentiation, capsular formation, existence of liver cirrhosis and patterns of interstitial invasion are important factors for determining the nature of the margin. The score of argyrophilic nuclear organizer regions (AgNOR) was examined in 5 cases showing typical interstitial invasion with the insidious type. In each case, the AgNOR score of the invading tumor cells was lower than that of tumor cells within the HCC nodules, but higher than benign hepatocytes in cirrhotic parenchyma. It clarified that the growth activity of well-differentiated HCC was rather suppressed upon their interstitial invasion.

Carcinoma, Hepatocellular↗
PubMed1995

Six cases of microscopic polyarteritis exhibiting acute interstitial pneumonia.

Out of 21 autopsy cases of microscopic polyarteritis (MPA), six cases that died of acute respiratory failure are described. All of these six cases exhibited pauci-immune necrotizing glomerulonephritis. Of these six cases, systemic vasculitis and respiratory failure occurred almost simultaneously in two, whereas respiratory failure developed when vasculitis recurred in the other four. Pathologically, pulmonary changes were diffuse and almost uniform in each case. Interstitial inflammatory cells (alveolitis), hyaline membrane, restructuring, and fibrosis were observed. The degrees of these changes differed from case to case; four cases showed predominantly exudative changes and two cases exhibited proliferative or organizing ones. Clinical and pathological features were consistent with acute interstitial pneumonia (AIP). Immunofluorescent and ultrastructural studies did not suggest deposition of immune complexes at the lesions of alveolitis. An etiologic agent could not be identified in these cases. Some lung lesions including pulmonary hemorrhage have been described in association with MPA; however, cases such as those presented here have rarely been reported. It was considered that AIP could be one of the pulmonary disorders in MPA. Furthermore, the possible pathogenetic role of antineutrophil cytoplasmic antibodies (ANCA) in the evolution of present lung lesion is discussed. Although ANCA were not examined in the present cases, these antibodies should be investigated in future cases.

Acute Disease↗
PubMed1995

Increased incidental detection and reduced mortality in renal cancer--recent retrospective analysis at eight institutions.

A retrospective survey of renal cell carcinoma between 1975 and 1993 at eight collaborating institutions was conducted with special reference to the incidental detection and mortality of renal cancer. The analysis demonstrated a recent dramatic increase in the frequency of incidental renal cancer, which now comprises two-thirds of all renal cancers, and a simultaneous recession in non-incidental or suspected renal cancer. Incidental renal cancer has remained unchanged during the last decade as far as patient demographics, occasion and method of detection, and the degree of tumor extension are concerned. On the other hand, the annual number of deaths from renal cancer has significantly decreased, and kidney-sparing surgery has been more frequently performed. These results indicate that incidental renal cancers are now in the majority, and earlier detection may contribute to improving the mortality and morbidity from the disease as a whole.

Aged↗
PubMed1995

Therapeutic effect of percutaneous ethanol injection on small hepatocellular carcinoma: evaluation with CT.

PURPOSE: To evaluate the therapeutic effect of percutaneous ethanol injection (PEI) on small hepatocellular carcinoma (HCC) with computed tomography (CT). MATERIALS AND METHODS: Sixty-seven patients with histologically proved HCC 3 cm or less in diameter underwent PEI. The patients were regularly followed up with sonography and contrast material-enhanced CT for more than 1 year (range, 12-96 months). The CT findings were evaluated for three tumor types distinguished on the basis of their appearance relative to that of the surrounding liver parenchyma: type 1 = hyperattenuating at the early phase (n = 39), type 2 = iso- or hypoattenuating at the early phase and hypoattenuating at the late phase (n = 18), and type 3 = isoattenuating (not detected) at both the early and late phases (n = 10). RESULTS: After PEI, a necrotic area of HCC and the surrounding liver parenchyma was characterized as hypoattenuating at both early and late phases of contrast-enhanced CT, regardless of the type. When an HCC appeared to be completely necrotic within 3 months after PEI, this status was retained until the latest observation in all but three cases. CONCLUSION: Contrast-enhanced CT can correctly depict PEI-induced necrosis in HCC and is reliable for evaluating the therapeutic effect of PEI.

Carcinoma, Hepatocellular↗