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Y Kondo

Publications and source records attributed to Y Kondo.

At least 73 records · Page 4Linked to original sources
PubMed2001

Hepatocellular carcinoma depicted as hypoattenuation on CT hepatic arteriography (CTA) and hyperattenuation on CT during arterial portography (CTAP).

We report a 68-year-old man with three nodules of hepatocellular carcinoma (HCC) in a cirrhotic liver; the largest nodule was 3.0cm in diameter. The nodules showed hypoattenuation on computed tomography (CT) hepatic arteriography (CTA) and hyperattenuation on CT during arterial portography (CTAP), indicating that the dominant vascularity of the HCC nodules may have been the portal vein. A biopsy specimen obtained from the nodules showed well differentiated HCC (Edmondson-Steiner grade I). The imaging findings of the nodules on both CTA and CTAP are unusual, in spite of the rather large size, so this seemed suggestive of the hemodynamic properties of relatively large nodules of well differentiated HCC.

Aged↗
PubMed2001

Sequence diversity and interrelationships among isolates of satsuma dwarf-related viruses.

The 3'-region of RNA2 of three viruses (Natsudaidai dwarf virus (isolate ND-1), and two unidentified isolates (LB-1, Az-1)), which were related to Satsuma dwarf virus (SDV), were sequenced. Phylogenetic analysis including the previously reported SDV-related viruses (Citrus mosaic virus (CiMV, Ci-968), Navel orange infectious mottling virus (NIMV, NI-1)) showed that they were classified into three groups, SDV (S-58), CiMV (Ci-968, LB-1, Az-1, ND-1), and NIMV (NI-1). The results suggested these groups might correspond to the three distinct virus species. ND-1, LB-1, and Az-1 were considered strains of CiMV, although they do not induce citrus mosaic on the fruit rind.

3' Untranslated Regions↗
PubMed2001

Role of stromal cells in osteoclast differentiation in bone marrow.

Bone marrow stromal cells have been considered to play an important role in osteoclast differentiation. However, the interaction of these cells in vivo has not been clearly demonstrated. To clarify this, we examined the distribution of alkaline phosphatase (ALPase) and tartrate-resistant acid phosphatase (TRAPase) activities as markers of osteoblastic and osteoclastic cells, respectively. Rat tibiae were fixed and embedded in Technovit 8100 or paraffin. ALPase and TRAPase activities were detected simultaneously on a plastic section by the azo-dye method. ALPase activity was detected on the plasma membranes of osteoblasts and some bone marrow fibroblastic stromal cells. These ALPase-positive cells were connected to each other by cytoplasmic processes, forming a cellular network in bone marrow. The ALPase activity of fibroblastic stromal cells tended to be stronger in those cells close to the bone surface than in the cells in the center of bone marrow. Reticular fibers in bone marrow were found to form a network. The ALPase-positive fibroblastic stromal cells may be reticular cells, because the localization of those cells was in accord with the localization of reticular fibers. The TRAPase-positive mononuclear cells and osteoclasts were mostly observed to be associated with the intensely ALPase-positive fibroblastic stromal cells. Immunoreactivity of osteoclast differentiation factor (ODF) was found in the fibroblastic stromal cells. These findings suggest that the network of ALPase-positive fibroblastic stromal cells in bone marrow serves as a guide for the migration of osteoclast precursor cells toward the bone surface, and may control the differentiation and activity of osteoclasts.

Acid Phosphatase↗
PubMed2001

Heat shock protein (HSP) 47 and collagen are upregulated during neointimal formation in the balloon-injured rat carotid artery.

Heat shock protein (HSP) 47, a collagen-specific molecular chaperone, is thought to be essential for the proper processing and secretion of procollagen molecules. We investigated the time course and localization of HSP47 and collagen expression after balloon catheter angioplasty in the rat carotid artery, based on the premise that accumulation of extracellular matrix components is a main feature of intimal hyperplasia in humans and in laboratory animals. Low levels of HSP47 expression were evident in uninjured carotid arteries. Northern blot analysis revealed that HSP47 mRNA expression was markedly stimulated 1--3 days after the induced injury and a high level was maintained for 7 days, followed by a gradual decline for up to 21 days after the injury. These changes in HSP47 expression paralleled changes in alpha 1(I) collagen expression. Immunohistochemical staining revealed colocalization of HSP47 and collagen in smooth muscle cells (SMCs) of the media and intima. In situ hybridization analysis showed that activated SMCs, which proliferated and migrated into the intima, expressed high levels of HSP47. In cultured human aortic SMCs, similar upregulation of HSP47 and alpha1(I) collagen by TGF-beta was noted. These results show that SMCs activated after balloon injury express high levels of HSP47 and collagen during cell proliferation and migration, hence an overproduction of collagen and development of intimal thickening. Thus, HSP47 plays a role in the formation and progression of neointima after angioplasty.

Animals↗
PubMed2001

Progressive cortical atrophy after forebrain ischemia in diabetic rats.

The morphological changes in the brain of diabetic rats were examined up to 8 weeks after transient forebrain ischemia produced by transient occlusion of both carotid arteries. Using histochemistry, we also examined the extent and rate of development of atrophic changes in the brain, appearance of astrocytes, activated microglia, and glucose transporter 1 (GLUT1) in streptozotocin-treated rat brains after forebrain ischemia. Atrophic changes appeared in the hippocampus in both non-diabetic-- and diabetic--ischemic groups 4 weeks after ischemia. In diabetic--ischemic rats, the atrophic changes were more severe and progressed more rapidly in the hippocampus, and were also observed in the frontal, temporal and parietal cortices, but not in any cortical areas of the non-diabetic--ischemic rats and non-ischemic--diabetic rats. We observed reduced density of GLUT1 in all cortical regions and hippocampus in ischemic-diabetic rats at 4--8 weeks, when the number of activated microglias and astroglias increased in all cortical regions. Although severe atrophic changes were observed in the gray matter, no serious injury was noted in the white matter in the diabetic-ischemic group. Our results indicate that brain ischemia in the presence of diabetes causes more severe late-onset damage culminating in brain atrophy, compared with non-diabetics.

Animals↗
PubMed2001

Identification of T-cell clones showing expansion associated with graft-vs-leukemia effect on chronic myelogenous leukemia in vivo and in vitro.

Although the graft-vs-leukemia (GVL) effect induced by donor leukocyte infusion (DLI) is thought to be mediated by T cells, their features, as well as target molecules, remain unknown. To characterize T cells that mediate the GVL effect on chronic myelogenous leukemia (CML), we studied T-cell repertoire in peripheral blood (PB) of two patients treated with DLI for relapsed CML after allogeneic bone marrow transplantation. Peripheral blood mononuclear cells (PBMCs) were obtained at 2-week intervals following DLI and examined for the presence of antigen-driven T-cell proliferation using complementarity-determining region (CDR) 3 size spectratyping of T-cell receptor beta chain subfamilies. Both patients exhibited transient proliferation of a limited number of T cells at a certain point in time (day 132 for patient 1 and day 75 for patient 2) after DLI in association with a decrease in the proportion of Philadelphia chromosome (Ph)-positive cells. In patient 2, who showed expansion of a BV16(+) T cell in PB, expansion of BV16(+) T cells with a similar CDR3 motif containing QDR to that of PB was demonstrated in the bone marrow (BM) sampled on day 33 and in the buccal mucosal tissue, showing chronic graft-vs-host disease (GVHD) on day 138 after DLI. When PBMCs obtained from patient 2 in remission were cultured with cryopreserved CML cells for 2 weeks, proliferation of a BV16(+) T cell with a CDR3 motif of QIR was induced in vitro. These findings indicate that transient proliferation of a limited number of T cells detected in PB 3-5 months after DLI probably reflects the GVL response against CML cells and may serve as a marker for the appearance of the GVL effect induced by DLI.

Adult↗
PubMed2001

Quantitative high-resolution microscopy on a suspended chain of gold atoms.

High-resolution electron microscope images of a suspended gold chain were analyzed quantitatively. The images of the suspended gold chain were recorded on videotapes, during in situ observation in an ultra-high-vacuum electron microscope. The chain consisted of four gold atoms free from any substrate. Image simulation verified that the gold chain has a center-top geometry. The simulation also showed that the chain has no glue atoms spinning around the axis of the chain. A spinning gold atom was shown to give 50% of the stationary atom in gray scale. By comparing the noise level of the observed image and the gray scale of single atoms such as C, Si, S, Cu, and Au, we verified that the Si and S atoms have almost twice as large contrast as the noise (peak-to-peak), and C atoms have almost the same contrast as the noise level. The analysis showed it critical to detect a single Si and S atoms.

Journal Article↗
PubMed2001

Characterization of the odor-active volatiles in citrus Hyuganatsu (Citrus tamurana Hort. ex Tanaka).

The volatile components of Hyuganatsu (Citrus tamurana Hort. ex Tanaka) peel oil, isolated by cold-pressing, were investigated by chemical and sensory analyses. According to chemical analysis by GC and GC-MS, limonene (84.0%) was the most abundant compound, followed by gamma-terpinene (6.9%), myrcene (2.2%), alpha-pinene (1.2%), and linalool (1.0%). Monoterpene hydrocarbons were predominant in Hyuganatsu peel oil. The odor-active volatiles in Hyuganatsu flavor were studied by GC-olfactometry and omission tests. The characteristic flavor was present in the oxygenated fraction. Flavor dilution (FD) factors of the volatile flavor components of the Hyuganatsu cold-pressed oil were determined by aroma extraction dilution analysis (AEDA). Furthermore, relative flavor activity was investigated by means of FD factor and weight percent. Ten kinds of odor compounds having Hyuganatsu-like aroma were detected by AEDA: limonene, linalool, octanol, neral, neryl acetate, tridecanal, trans-carveol, cis-nerolidol, trans,trans-farnesyl acetate, and trans,trans-farnesol. Linalool and octanol were regarded as the most odor-active or key compounds of Hyuganatsu aroma. Diluted solutions of linalool and octanol of approximately 2 ppm gave a fresh and fruity aroma note similar to Hyuganatsu flavor.

Chromatography, Gas↗
PubMed2001

Diclofenac-induced gastric mucosal fluorescence in rats.

We previously reported that the gastric mucosa emits fluorescence of porphyrins at the onset of gastric lesions induced by hemorrhagic shock. In this study, we investigated whether the fluorescent substance concerns with the gastric mucosal injuries induced by diflofenac, a nonsteroidal antiinflammatory drug (NSAID). In the gastric mucosa treated with diclofenac, lesions were generated and myeloperoxidase activity increased. Diclofenac administration also increased thiobarbituric acid-reactive substances, a index of tissue peroxidation. After diclofenac treatment, the gastric mucosal fluorescence intensities rose. HPLC analysis demonstrated that the fluorescent substances were mesoporphyrin and protoporphyrin, which were the same as found in hemorrhagic shock. Pretreatment of the tissue with radical scavenging substances, catalase and troxipide, restrained the increase of mucosal fluorescence intensity, tissue peroxidation, and lesion formation. These findings indicate that diclofenac treatment induced the generation of porphyrins as well as tissue peroxidation in gastric mucosal tissue. This study suggests that autofluorescence observation is a useful tool to identify diclofenac-induced gastric injury.

Animals↗
PubMed2001

Relationship between enantioselectivity of alternative molecularly imprinted polymeric membranes and species of amino acid residues composing chiral recognition sites.

Molecularly imprinted polymeric membranes with tetrapeptide residue H-Asp(OcHex)-Asp(OcHex)-Asp(OcHex)-Asp(OcHex)-CH2- (DDDD) or H-Glu(OBzl)-Glu(OBzl)-Glu(OBzl)-Glu(OBzl)-CH2- (EEEE) were prepared during membrane preparation (casting) processing in the presence of print molecules. The Boc-L-Trp imprinted polymeric membranes thus obtained showed adsorption selectivity toward Ac-L-Trp from its racemic mixtures. From adsorption isotherms of Ac-Trp, the chiral recognition site, that had been formed by the presence of print molecules in the membrane preparation process, exclusively recognized Ac-L-Trp that possessed the same configuration of the print molecule. The affinity constants between chiral recognition sites in the membrane and Ac-L-Trp was determined to be 1.00 x 10(4) mol(-1) dm3 and 1.08 x 10(4) mol(-1) dm3 for the DDDD and EEEE membranes, respectively. Enantioselective electrodialysis could be attained by applying an optimum potential difference to give permselectivity, with a value close to its adsorption selectivity.

Amino Acids↗
PubMed2001

Treatment of bladder cancer cells in vitro and in vivo with 2-5A antisense telomerase RNA.

Bladder cancer is the most common malignant tumor of the urinary tract. Novel treatment approaches are essential because of the failure of current treatment options to cure a high percentage of patients. Telomerase, a ribonucleoprotein, is detected in almost all bladder cancer, but not in normal bladder tissues. Therefore, telomerase is expected to be a very promising candidate for targeted therapy of bladder cancer. In this study, we synthesized a 19-mer antisense oligonucleotide against the RNA component of human telomerase (hTR) linked to a 2-5A molecule (2-5A-anti-hTR) and investigated its antitumor effect against bladder cancer cells. The 2-5A antisense strategy relies on the recruitment and activation of RNase L at the site of targeted RNA sequence. Here we demonstrate that treatment with 2-5A-anti-hTR reduced the viability of seven bladder cancer cell lines (UM-UC-2, UM-UC-3, UM-UC-6, UM-UC-9, UM-UC-14, RT4 and T24) expressing telomerase activity to 21-55% within 4 days. The cytotoxicity was mainly due to induction of caspase-dependent apoptosis. In contrast, normal fibroblast WI38 cells lacking telomerase activity were resistant to the treatment. Furthermore, treatment of subcutaneous UM-UC-2 tumors in nude mice with 2-5A-anti-hTR significantly suppressed the tumor growth through induction of apoptosis (P < 0.001). These findings may offer a strong support to the feasibility of the 2-5A-anti-hTR treatment for human bladder cancer.

Animals↗
PubMed2001

Tumour suppressor activity of human imprinted gene PEG3 in a glioma cell line.

BACKGROUND: Mouse imprinted gene Peg3 encodes a large C2H2 type zinc finger protein with unique characteristics. Peg3 knockout mice were found to show an impairment in maternal behaviour of the adult female. Mouse Peg3 is located on the proximal region of chromosome 7 which is syntenic to the long arm of human chromosome 19. It has been reported that a loss of heterozygosity (LOH) of chromosome 19q occurs frequently in several glioma types. RESULTS: We isolated human PEG3 cDNA. Both human and mouse PEG3 were strongly expressed in the adult brain and the Peg3 protein was localized in the nuclei of both neurones and glial cells. A significant decrease in PEG3 expression was more commonly observed in glioma cell lines as compared with that in primary cultures of astrocytes. Transfection of PEG3 cDNA in a glioma cell line resulted in a loss of tumorigenicity in nude mice. CONCLUSIONS: The human PEG3 gene is a paternally expressed imprinted gene. Introduction of PEG3 cDNA into the glioma cells suggests that human PEG3 protein functions as a tumour suppressor. Human PEG3 is located on 19q13.4 and is one of the candidates for tumour suppressor genes that are predicted to be sited in gliomas.

5' Untranslated Regions↗
PubMed2001

Sialolipoma: a report of seven cases of a new variant of salivary gland lipoma.

AIMS: We propose the designation 'sialolipoma' to establish and characterize a new category of benign lipomatous tumour occurring in salivary glands. Until now, these tumours have not been regarded as a distinct entity in the salivary glands. METHODS AND RESULTS: We evaluated the clinicopathological and immunohistochemical features of seven sialolipomas among 2051 surgically resected primary salivary gland tumours deposited in our files. The seven patients with sialolipoma were five men and two women, aged 20-75 years (mean: 54.4 years). Five tumours had arisen in the parotid gland, one in the soft palate, and one in the hard palate. The tumours ranged from 10 to 60 mm (mean: 38 mm) in maximum diameter. Histologically, the tumours were characterized by a well circumscribed mass composed of glandular tissue and mature adipose elements. The adipose elements in the tumours arising in the parotid gland were more abundant than those arising in the minor salivary gland. The glandular components consisted of ductal, acinar, basal and myoepithelial cells, and closely resembled the cellular and structural compositions of normal salivary gland tissues. These findings were confirmed by immunohistochemical and ultrastructural studies. These components had no atypia, except for the presence of some minor variations, e.g. ductal ectasia with fibrosis and focal oncocytic metaplasia. In all cases, cell proliferative activity, as assessed by Ki67 (MIB1) immunostaining, was low. From these findings, it is likely that our cases were lipomas with secondary entrapment of the salivary gland elements. No recurrence was seen in all cases after superficial parotidectomy, or after surgical excision in the patients with palatal tumours. CONCLUSIONS: We regard sialolipoma as a distinct variant of salivary gland lipoma that can occur in both the major and minor salivary glands. Superficial parotidectomy, or surgical resection in the case of palatal tumours, is an appropriate treatment for this benign tumour.

Adult↗
PubMed2001

Taurine inhibits development of atherosclerotic lesions in apolipoprotein E-deficient mice.

1. The effects of taurine on the development of atherosclerotic lesions were investigated in apolipoprotein (apo) E-deficient mice, an animal model with severe hypercholesterolaemia and extensive atherosclerosis. These mice were fed a normal laboratory chow containing 2% taurine for 12 weeks. 2. Serum total cholesterol was significantly elevated after 12 weeks treatment with taurine. This elevation was due to increases in very low-density lipoprotein- and low-density lipoprotein-cholesterol. 3. Despite such effects on serum lipoproteins, analysis using en face oil red O staining revealed that taurine reduced the area of arterial lipid accumulation by 28%, as measured quantitatively as an index of atherosclerosis. Histological examination also demonstrated a decrease in the size of aortic lesions in taurine-treated mice. 4. Serum levels of thiobarbituric acid reactive substances (TBARS) in apoE-deficient mice were higher than in normolipidaemic C57BL/6J mice. Serum TBARS levels were significantly decreased by 12 weeks treatment of apoE-deficient mice with taurine. 5. Thus, taurine prevents the formation of atherosclerotic lesions, independently of serum cholesterol levels, and the results suggest that the anti-oxidative effects of taurine are related to its anti-atherosclerotic actions.

Animals↗
PubMed2001

Characterization of hyperplastic foci observed in surgical specimens of hepatocellular carcinoma.

By reviewing previous surgical specimens of hepatocellular carcinoma, 17 cases with hyperplastic foci (HPF) characterized by discernible increase in nuclear densities, could be histologically selected. Nuclear densities of HPF and control hepatic parenchyma were assessed quantitatively by counting the nuclear number of hepatic cells, and proliferating cell nuclear antigen labeling index was measured. HPF occurred multifocally, confined within a lobular unit, smoothly merging into surrounding hepatic parenchyma. Nuclear densities of HPF were 1.71 times greater than those of control hepatic parenchyma. The hepatocytes of HPF also showed significantly higher proliferative activities than those of control parenchyma. In addition, noticeable structural distortions, such as focal trabecular thickening or microacinar formation of hepatocytes, were sometimes observed in HPF. However, these HPF seemed to be distinguished from minute de novo hepatocellular carcinoma (HCC) or intrahepatic HCC metastasis, because of paucity of distinctive atypical changes, and intimate correlation with neighboring hepatocytes. Several adjacent HPF were aggregated to form a much larger unit of a hyperplastic area with loss of fibrous septa of liver cirrhosis. It was suggested that grossly detectable large regenerative nodules are produced via fusion of several adjacent HPF.

Adult↗
PubMed2001

Urothelial mucosal concentration of levofloxacin administered before transurethral resection: Is the mucosal concentration predictable?

BACKGROUND: Although it is an established surgical technique, transurethral resection (TUR) is associated with a certain incidence of postoperative bacteriuria. Assessment was made whether the urothelial mucosal concentration of an antibiotic administered before TUR was high enough to decrease the incidence of urinary tract infection (UTI). Also investigated were factors predicting the organ concentration. METHODS: Forty-nine patients (45 men and four women aged 51-79 years with a median age of 70 years) who underwent TUR between August 1996 and September 1997 were enrolled in the study. Each patient received 200 mg of levofloxacin (LVFX) about two hours before surgery. Blood and bladder urine were collected and urothelial mucosa was harvested at the time of TUR. Then the LVFX concentration in these samples was measured using high-performance liquid chromatography. The association between drug levels, or the ratio to the serum concentration, and factors likely to affect the vascular system that delivers the drug (age, bodyweight, blood pressure, pulse rate, total cholesterol and diabetes mellitus) were investigated. RESULTS: The mean serum drug level was 2.4 microg/mL, and it was 206.4 microg/mL in the urine and 5.7 microg/mL in the urothelial mucosa. The mean ratio of the mucosal to serum concentrations was 2.6. The urinary drug concentration showed no association with any of the factors assessed, while the serum concentration decreased with increasing bodyweight (P = 0.03). As the diastolic blood pressure increased, both the mucosal drug concentration and the mucosa/serum ratio decreased (P < 0.01). When the relationship between the serum and mucosal concentrations was investigated, no correlation was found. However, the mucosa/serum ratio (indicating the transfer of LVFX from the blood) was positively correlated with the mucosal concentration. CONCLUSION: Preoperative administration of LVFX was demonstrated to have potential value for the prophylaxis of UTI after TUR. Both the mucosal concentration and the mucosa/serum ratio were correlated with the diastolic blood pressure. As the diastolic blood pressure seems to be an indicator of the tissue concentration of LVFX, it may be possible to set the optimum dose based on the diastolic pressure.

Aged↗