Biomedical subjects

Y Kondo

Publications and source records attributed to Y Kondo.

At least 253 records · Page 14Linked to original sources

PubMed1998

Assessing the suitability of gastric carcinoma for limited resection: endoscopic prediction of lymph node metastases.

Some early gastric carcinomas are free of lymph node involvement; however, the pathosis of these carcinomas is neither well understood nor reflected in the choice of less extensive treatment. We investigated the relation of nodal involvement to pathologic findings of the resected specimens. We present promising standards for predicting the nodal status of early gastric carcinomas, contributing to the indication for limited surgery. The relation of lymph node metastasis to tumor size, infiltration depth, macroscopic appearance, and histologic type of early gastric carcinomas were investigated in 1470 patients with a single primary early gastric carcinoma. Of these carcinomas, 763 were limited to the mucosa (mucosal carcinoma) and 707 to the submucosa (submucosal carcinoma). The overall incidence of lymph node metastasis was 9.0%: 2.1% in mucosal carcinomas and 16.5% in submucosal ones, with a significant (p < 0.001) difference of nodal involvement between the two. The macroscopically elevated or compound-type carcinomas 10 mm or less in diameter were all node-negative, whereas some depressed-type carcinomas were node-positive. The incidence of undifferentiated carcinomas increased with tumor diameter, irrespective of whether they were mucosal or submucosal carcinomas, and they were significantly more node-positive than were differentiated carcinomas: p < 0.001 for mucosal carcinomas and p < 0.05 for submucosal ones. The carcinomas satisfying the following criteria are node-negative and eligible for limited surgery: (1) mucosal carcinoma; (2) elevated lesion < 10 mm in diameter; (3) differentiated adenocarcinoma; and (4) no ulcer or ulcer scar. The other carcinomas are potentially node-positive and standard surgery is recommended.

Adenocarcinoma↗

PubMed1998

Assessing the suitability of gastric carcinoma for limited resection: histologic differentiation of endoscopic biopsy.

Histologically differentiated adenocarcinoma satisfies one of the criteria for limited surgery for mucosal carcinoma of the stomach: however, the histology of the endoscopic biopsy specimen is often different from that of the resected specimen. The medical records of 1018 early gastric carcinomas were retrospectively analyzed to investigate the relation between the histologies of biopsy and resected specimens. Regression analysis showed that the histologies of biopsy specimens were significantly related to those of resected specimens (r = 0.677, n = 5, p = 0.0288) for the mucosal carcinomas, but their relation was not significant for the submucosal carcinomas (r = 0.677, n = 5, p = 0.2091). By analyzing the 344 differentiated mucosal carcinomas, moderately differentiated tubular adenocarcinomas were seen to be frequently less differentiated at resection. The histology of the biopsy specimens from mucosal carcinoma of the stomach grossly satisfies one of the criteria for limited surgery, but moderately differentiated adenocarcinoma may not be suitable for this treatment.

Adenocarcinoma↗

PubMed1998

Tumor recurrence following resection for early gastric carcinoma and its implications for a policy of limited resection.

Some patients suffer postoperative recurrence after curative resection of early gastric carcinoma. This study reviewed consecutive patients with a single primary lesion and analyzed the relation between the pathologic findings and recurrence of early gastric carcinomas for determining indications for limited surgery. Among the 1585 consecutive patients with a solitary primary lesion of an early gastric carcinoma who had undergone curative surgery between 1963 and 1989 at one general hospital, pathologic findings relating to recurrence were analyzed according to Japan's General Rules for Gastric Cancer Study in Surgery and Pathology. Of these carcinomas, mucosal carcinomas comprised 701 (44.2%) and submucosal ones 884 (55.8%). The total recurrence rate in this series was 1.0%. Submucosal carcinomas (1.6%) were significantly (p < 0.02) more recurrent than mucosal ones (0.29%). Of the 16 patients with recurrence, 10 (62.5%) died within 5 years after surgery, frequently because of blood-borne metastasis. Macroscopically elevated components, the degree of histologic differentiation, and lymph node metastasis significantly contributed to the postoperative recurrence. After detailed analysis of submucosal carcinomas, it is strongly suspected that carcinomas with a macroscopically elevated component were significantly associated with nodal involvement and microvessel invasion, and that these abnormalities lead to recurrence. Among the early gastric carcinomas, differentiated submucosal carcinomas with a macroscopically elevated component, lymph node metastasis, or both have the most potential of recurrence after surgery. Mucosal carcinomas must be restricted to limited surgery, but, blood-borne metastasis should be carefully avoided.

Adenocarcinoma, Mucinous↗

PubMed1998

Alterations in the distribution of plasma fibronectin and the ultrastructure of podocytes in the peripheral glomerular loops in nephrotic rats.

Glomerular distribution of rat plasma fibronectin was examined during the course of puromycin (PAN)- and daunomycin (DM)-induced nephrosis. In control animals, fibronectin was detected in the mesangial matrix and along the glomerular basement membrane (GBM), closely associated with the plasma membrane of glomerular cells. In peripheral loops, immunoprecipitates were preferentially distributed in the laminae rarae externa and interna. Fibronectin was densely precipitated in a glomerulosclerotic lesion induced by DM at 8 weeks after the injection. In peripheral loops, loss and reconstruction of epithelial foot processes occurred in PAN nephrosis but the change was accompanied by negligible perturbation of fibronectin distribution in the lamina rara externa. In contrast, a remarkable decrease of fibronectin was observed in DM nephrosis, unrelated to the presence or absence of foot processes. The decrease in immunoreactivity for fibronectin in the lamina rara externa seemed to have no association with podocyte attachment to or detachment from the GBM. Plasma fibronectin distributed in the lamina rara externa is not directly involved in the modification of podocyte configuration or podocyte attachment, although its spatial distribution may have some functional significance for preserving the ultrastructure of the GBM.

Animals↗

PubMed1998

The nucleotide sequence of the coat protein genes of satsuma dwarf virus and naval orange infectious mottling virus.

The sequence of the 3'-terminal 4320 and 2409 nucleotides were determined for RNA2 of satsuma dwarf virus (SDV) and navel infectious mottling virus (NIMV). Both sequences contained a part of a long open reading frame which encodes larger and smaller coat proteins (CPs) at the 3'-terminus followed by a 3'non-coding region upstream of a poly (A) tail. Amino acid sequence identity for larger and smaller CPs ranged 81-84% and 68-78%, respectively, among SDV, NIMV and the previously sequenced citrus mosaic virus (CiMV). No significant sequence similarity was found between the CPs of SDV or NIMV and those of the como-, nepo- or other viruses. The nucleotide sequence identity of the 3' non-coding region of RNA2 were 68%-78% among SDV, CiMV and NIMV. These results suggest that SDV, CiMV and NIMV are distinct, though related, viruses. They may be assigned as members of the new genus, which is close to the genera of Comovirus and Nepovirus.

Amino Acid Sequence↗

PubMed1998

Demonstration of microaneurysms at the interlobular arteries of the kidneys in microscopic polyangiitis: a three-dimensional study.

Aneurysms, mostly saccular, of the medium-sized muscular arteries are frequently encountered in classic polyarteritis nodosa, whereas their occurrence in smaller arteries is unclear. The objective of this study is to clarify the three-dimensional morphology of the small-sized muscular arteries involved in microscopic polyangiitis (MPA). Six autopsy cases of MPA of the acute inflammatory stage were chosen. Using serial paraffin-embedded sections of the kidney, vasculitic lesions observed in the interlobular arteries were three-dimensionally reconstructed. All of the 19 lesions showed microaneurysms, of which 18 were sausage-shaped and the other was saccular. In the former type, average outer diameter at the most expanded point was 235.4 +/- 83.8 microm (mean +/- SD), which was 2.78 +/- 0.73 times that of an uninvolved adjacent arterial diameter. The major axis-minor axis ratio in a cross-aneurysmal section was 1.17 +/- 0.16, indicating rather regular centrifugal expansion of the aneurysm. The aneurysmal length was 742.7 +/- 254.8 microm. These sausage-type aneurysms showed whole circumferential vasculitic involvement, whereas the saccular-type aneurysm contained an uninvolved arterial portion. In both types, the luminal spaces showed similar three-dimensional features to the outer surface of microaneurysms It was concluded that the interlobular arteries of the kidneys in MPA were characterized by formation of microaneurysms, most of which were sausage-shaped

Actins↗

PubMed1998

The ACAT inhibitor HL-004 inhibits cholesterol absorption and lowers serum cholesterol in rats.

1. HL-004 decreased absorption of cholesteryl ester from the intestine into the lymph in a rat lymph-fistula model. 2. HL-004 reduced serum cholesterol level in acute cholesterol-fed rats. 3. HL-004 simultaneously decreased hepatic cholesteryl ester content and increased free cholesterol in cholesterol-fed rats. 4. These findings suggest that: (1) the hypocholesterolemic effect of HL-004 is principally due to inhibition of cholesterol absorption via inhibition of ACAT in the intestine; and (2) changes in hepatic cholesterol metabolism due to direct inhibition by HL-004 of hepatic ACAT may account in part for reduction of serum cholesterol level by HL-004.

Absorption↗

PubMed1998

Etiological analysis of focal nodular hyperplasia of the liver, with emphasis on similar abnormal vasculatures to nodular regenerative hyperplasia and idiopathic portal hypertension.

Pathological studies were performed on 23 cases of focal nodular hyperplasia (FNH) under the hypothesis that FNH is a hyperplastic lesion caused by abnormal vasculatures of portal tracts within the nodule. For a comparison of the histological features of portal tracts, nodular regenerative hyperplasia (NRH), idiopathic portal hypertension (IPH), chronic hepatitis and so-called normal liver were used as control tissues. Extranodular areas of FNH nodules were also examined. Clinical data were briefly summarized. Most of the portal tracts within FNH nodules showed various abnormal findings, such as dilatation and/or stenosis of portal vein, muscular thickening of arterial wall with dilated or stenotic lumina, lymphocyte infiltration, and bile ductule proliferation. However, portal vein thrombi were not found. These findings were not thought to represent compensatory reaction to portal vein thrombosis. Similar abnormal features were also observed in extranodular areas of FNH although to a milder degree. These abnormal features resembled those of NRH and IPH. Moreover, the characteristic scar-like tissues within FNH nodules were proved to be abnormally large portal tracts including large feeding arteries, portal veins and bile ducts. It has been believed that septa and scar-like tissue within FNH nodules are not portal tracts and that arterial malformation independent of portal tracts are related to the development of FNH. In addition, venous structures within FNH modules have until now not been considered to be portal veins. However, this study revealed that severe anomaly of portal tracts including portal veins and hepatic arterial branches existed in FNH nodules. Moreover, portal tracts in extranodular areas were also abnormal. Clinically, only one patient had a history of oral contraceptives. Based on these findings, congenital anomaly of the portal tracts histologically resembling the abnormal portal tracts of NRH and IPH may be related to the pathogenesis of FNH.

Adult↗

PubMed1998

Mucoepidermoid carcinoma arising in Warthin's tumour of the parotid gland: report of two cases with histopathological, ultrastructural and immunohistochemical studies.

AIMS: Malignant transformation of Warthin's tumour (WT) is a rare event. We present two cases of mucoepidermoid carcinoma (MEC) arising in WT in the parotid gland. METHODS AND RESULTS: Two cases of MEC arising in WT, which were found in 185 cases of WT of the parotid gland, were investigated by light and electron microscopy, and immunohistochemistry. Both cases had largely similar macroscopic and histological features with some differences. Histologically, the tumours consisted mainly of WT with multilayered hyperplastic arrangements of oncocytic cells and focal squamous and goblet cell metaplasia. In the same tumour mass, however, the features of MEC were observed with invasion to adjacent adipose tissue. A transitional zone between WT and MEC was evident. Both patients were alive and well without evidence of recurrence 30 and 34 months after surgery, respectively. Electron microscopy revealed that cyst lining epithelial cells in WTs had abundant mitochondria whereas some of the MEC cells contained numerous tonofilaments and mucinous granules. Immunohistochemically, oncocytic cells of WTs were strongly positive for mitochondria and SalylTn was extensively stained in MECs. The labelling index for Ki67 was obviously higher in the carcinoma cells than the epithelial cells of WT. CONCLUSIONS: Our cases confirmed the possibility of malignant transformation of the epithelial component in WT to MEC.

Adenolymphoma↗

PubMed1998

Down-regulation of the noradrenaline transporter by interferon-alpha in cultured bovine adrenal medullary cells.

The aim of this study was to investigate the effect of long-term treatment with interferon (IFN)-alpha on the noradrenaline transporter of bovine adrenal medullary cells. Treatment of cultured adrenal medullary cells with IFN-alpha caused a decrease in uptake of [3H]noradrenaline by the cells in time (4-48 h)- and concentration (300-1,000 U/ml)-dependent manners. IFN-beta also inhibited [3H]noradrenaline uptake to a lesser extent than did IFN-alpha, whereas IFN-gamma had little effect. An anti-IFN-alpha antibody reduced the effect of IFN-alpha on [3H]noradrenaline uptake. Saturation analysis of [3H]noradrenaline uptake showed that the inhibitory effect of IFN-alpha was due to a reduction in the maximal uptake velocity (Vmax) values without altering apparent Michaelis constant (Km) values. Incubation of cells with IFN-alpha caused a translocation of protein kinase C from the soluble to the particulate fraction in the cells. The effect of IFN-alpha on [3H]noradrenaline uptake was diminished in protein kinase C-down-regulated cells. Incubation of cells with IFN-alpha for 48 h significantly reduced the specific binding of [3H]desipramine to crude plasma membranes isolated from cells. Scatchard analysis of [3H]desipramine binding revealed that IFN-alpha decreased the maximal binding (Bmax) values without any change in the dissociation constant (K(D)) values. These findings suggest that IFN-alpha suppresses the function of noradrenaline transporter by reducing the density of the transporter in cell membranes through, at least in part, a protein kinase C pathway.

Adrenal Medulla↗

PubMed1998

Analysis of conserved ambisense sequences within GB virus C.

No analysis has been done of the ambisense of GB virus C (GBV-C). When the anti-genomes of 16 reported sequences of GBV-C were analyzed, nucleotide codons 1758 and 1402 within the anti-genome were conserved initiation and stop codons, respectively. Nucleotide sequences were also determined within the same region of 22 GBV-C strains. The anti-genomes of 38 sequences were translated and a consensus sequence was determined. In accordance with the consensus sequence, overlapping peptides were synthesized and used for the detection of anti-synthetic peptide antibodies by ELISA. The positivity of antibodies among sera with GBV-C RNA was significantly higher than among sera without GBV-C RNA (66.7% vs. 15.6%), regardless of the simultaneous presence of hepatitis B surface antigen or antibodies to hepatitis C virus (P < .05). These results indicated that a novel protein associated with GBV-C might be expressed from the ambisense of this virus.

Antibodies, Viral↗

PubMed1998

Routes of hepatic metastasis of gallbladder carcinoma.

This clinicopathologic study aims to clarify routes of hepatic metastasis of gallbladder carcinoma. Nineteen liver specimens obtained by extensive hepatectomy performed for the treatment of advanced gallbladder carcinoma were analyzed. We defined hepatic metastasis as a discrete hepatic lesion separate from the primary tumor and paid special attention to portal tracts at the margins of direct hepatic invasion. Eleven early metastatic foci were demonstrated histologically in 6 cases, most commonly in segments adjacent to the gallbladder. All cases with hepatic metastasis had direct hepatic invasion. Nine of the 11 metastatic lesions were located within the portal tracts or accompanied by invasion into the portal tracts. Because they are in continuity with areas of direct hepatic invasion, the portal tracts at the invasive margin often were involved by cancer cells that spread along these tracts. These results suggest that the most important route in development of hepatic metastasis from gallbladder carcinoma is along the portal tracts after direct hepatic invasion.

Aged↗

PubMed1998

Evaluation of a sensitive, in vitro bioassay for chicken thyroid stimulating hormone using FRTL-5 cells, a rat thyroid cell line.

An in vitro bioassay for mammalian thyroid stimulating hormone (TSH) based on TSH-induced cyclic adenosine 3',5'-monophosphate (cAMP) production in FRTL-5 cells, a rat thyroid cell line, was used to measure chicken TSH. The addition of chicken pituitary homogenate equivalent to > or = 25% of a chicken pituitary gland to cultured FRTL-5 cells increased cAMP within these cells in a dose-dependent manner. The glycoprotein fraction derived from the pituitary homogenate was further fractionated by isoelectric focusing within a pH range of 5 to 11. Analysis of the focused fractions by the bioassay detected three major components with isoelectric points of 9.30, 7.12, and 3.82, in addition to several minor ones distributed over a wide range of pH, from alkaline to acidic. The isoelectric focusing profile obtained by the bioassay was clearly different from those obtained by radioimmunoassay for chicken LH and radioreceptor assay for chicken FSH, indicating that fractions contained chicken TSH. The homogenate of the cephalic portion of the chicken anterior pituitary gland was 4.46 times more active than that of the caudal portion in the bioassay, which is consistent with previous findings on localization of TSH in the chicken pituitary. We conclude that the bioassay using FRTL-5 rat thyroid cells is a sensitive, specific, and time-saving method of measuring chicken TSH.

Analysis of Variance↗

PubMed1998

Antisense telomerase treatment: induction of two distinct pathways, apoptosis and differentiation.

Telomerase, the enzyme that elongates telomeric DNA (TTAGGG)n, may be involved in cellular immortality and oncogenesis. To investigate the effect of inhibition of telomerase on tumor cells, we transfected the antisense vector against the human telomerase RNA into human malignant glioma cells exhibiting telomerase activity. After 30 doublings, some subpopulations of transfectants expressed a high level of interleukin-1beta-converting enzyme (ICE) protein and underwent apoptosis. In contrast, other subpopulations also showed enhanced ICE protein but escaped from apoptotic crisis and continued to grow, although their DNA synthesis, invasive ability, and tumorigenicity in nude mice were significantly reduced. Surviving cells demonstrated increased expression of glial fibrillary acidic protein and decreased motility, consistent with a more differentiated state. These cells also contained enhanced expression of the cyclin-dependent kinase inhibitors (CDKIs) p21 and p27. Treatment of surviving nonapoptotic cells with antisense oligonucleotides against p27, but not p21, induced apoptotic cell death, suggesting that p27 may have protected differentiating glioma cells from apoptosis. These data show that treatment with antisense telomerase inhibits telomerase activity and subsequently induces either apoptosis or differentiation. Regulation of these two distinct pathways may be dependent on the expression of ICE or CDKIs.

Animals↗

PubMed1998

Assessment of autonomic nervous activity during gastrointestinal endoscopy: analysis of blood pressure variability by tonometry.

We continuously measured blood pressure by tonometry in 30 patients during endoscopy to determine the influence of upper gastrointestinal endoscopy on cardiac events. Patients were divided into two groups: one group treated with scopolamine butylbromide as premedication (SB group) and another group without premedication (C group). Time- and frequency domain analyses of beat-to-beat systolic blood pressure variability were performed for 128 consecutive beats. For time-domain analysis, we calculated the coefficient of variation of systolic blood pressure (CV(BP)). For the frequency domain analysis, we determined the low-frequency (LF(BP); 0.04-0.15 Hz) and high-frequency (HF(BP); 0.15-0.40 Hz) powers of the variation in systolic blood pressure and the ratio of LF(BP) to HF(BP) (LF(BP)/HF(BP)) during endoscopy. The CV(BP) and HF(BP), indicators of parasympathetic tone, increased in the early phase of endoscopy but decreased significantly in the middle and late phases compared with the pre-endoscopy value. The ratio of LF(BP)/HF(BP), an indicator of indirect sympathetic tone, increased throughout the endoscopic procedure. Moreover, premedication with scopolamine butylbromide prevents the excessive parasympathetic nervous reflex when an endoscope passes through the upper digestive tract and also brings both decreased parasympathetic tone and increased sympathetic tone at the late phase of endoscopic procedure. Our results indicate that gastrointestinal endoscopy induced an autonomic nervous abnormality, which may contribute to the occurrence of cardiac events during endoscopic procedures.

Adult↗

PubMed1998

Brugada syndrome associated with an autonomic disorder.

A 44 year old man with Brugada syndrome and ventricular fibrillation had an autonomic disorder, shown by spectral analysis of heart rate variability and 123I-MIBG myocardial scintigraphy. Periodic variation of the ST segments was detected by Holter ECG. Increased high frequency power (0.15-0.40 Hz), an index of parasympathetic nerve activity, was observed just before ST segment elevation. In addition, local dysfunction of sympathetic nerves in the left ventricle was detected by 123I-MIBG myocardial scintigraphy. Unbalanced autonomic nerve function plays an important role in inducing Brugada-type ECG signs.

Adult↗

PubMed1998

Effect of polyelectrolyte complex (PEC) on human periodontal ligament fibroblast (HPLF) functions in the presence of glucocorticoids.

Cell functions in vivo are stimulated by extracellular matrices, vitamins, growth factors, and hormones. In this paper, the effects of glucocorticoids, dexamethasone (Dex), and Cortexrone (Cor) on the growth and differentiation of human periodontal ligament fibroblast (HPLF) were discussed in relation to a polyelectrolyte complex (PEC) consisting of polysaccharides (chitin, cellulose derivatives, and chitosan) as a tissue-culture material. A Dex-treatment at a concentration of 10(-)-10(-7) M inhibited one-half of HPLF growth in comparison with 10(-9) M Dex-treatment and no additive medium and produced aggregates on the chitosan-sulfated chitin PEC (SPECs) with regard to the degree of sulfate substitution. On the chitosan-sulfated cellulose PEC, 10(-7)-10(-9) M Dex-treatment promoted HPLF growth and inhibited the production of aggregates. On the other hand, a Cor-treatment, a mineral corticoid, which inhibits the interaction between Dex and its receptor, increased HPLF growth on SPEC141, but the HPLF did not construct aggregates. A Dex and Cor mixture-treatment inhibited one-third HPLF growth in comparison with 10(-5) M Dex-treatment and produced aggregates on PEC. The cooperative effect of both the culture material and hormones was found to control HPLF growth and morphology. The alkaline phosphatase (ALPase) activities of HPLF increased with an increase in the Dex and Cor concentration. The value of Dex-treated HPLF ALPase activity demonstrated a two-fold increase from that with Cor-treatment. The ALPase activity of Dex and Cor mixture-treated HPLF on PEC decreased with an increase in the Cor concentration, because Cor increased HPLF growth on PEC. In using carboxymethylated chitin derivatives as the polyanion, HPLF decreased in cell growth and produced aggregates in the absence of the additives, suggesting that PEC induces HPLF differentiation using only the stimulation of the material surface.

Alkaline Phosphatase↗

PubMed1998

Deimination of 70-kD nuclear protein during epidermal apoptotic events in vitro.

Peptidylarginine deiminase (PAD) is the enzyme responsible for converting protein-bound arginine residues to citrulline. It has recently been shown that a number of epidermal proteins, including filaggrin, trichohyalin, and keratins, are deiminated by the action of PAD, suggesting a possible role for protein deimination during the final stages of epidermal differentiation. We report here a novel PAD substrate found during the course of identifying deiminated proteins in cultured rat epidermal keratinocytes. We found that a 70-kD protein localized to the periphery of the nucleus was preferentially deiminated after ionomycin treatment in the presence of 2 mM calcium and was associated with apoptotic events in these cells. Furthermore, we discovered that the deimination of nuclear protein could be induced by transfection of a PAD cDNA into rat epidermal keratinocytes. These data suggest that PAD may act on the 70-kD nuclear protein to induce disassembly of the nuclear lamina and promote apoptosis during terminal epidermal differentiation.

Animals↗