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J Takeuchi

Publications and source records attributed to J Takeuchi.

At least 145 records · Page 8Linked to original sources

Immunohistochemical techniques for detection of dermatan sulfate proteoglycan in tissue sections.

Dermatan sulfate proteoglycan chains were detected in tissue sections treated with chondroitin B-lyase (0.01 units/ml) in 20 mM Tris-HCl (pH 8.0) for 1 hr, followed by staining with antibody 9A2 specific for unsaturated uronic acid coupled to N-acetylgalactosamine-4 sulfate. In contrast, after treatment with chondroitin B-lyase, no positive staining was observed with antibodies 3B3 and 1B5 which react to the unsaturated uronic acid coupled to N-acetylgalactosamine 6-sulfate and unsaturated uronic acid coupled to N-acetylgalactosamine, respectively. The distribution of dermatan sulfate thus revealed was confirmed by comparison with that found by monoclonal antibody 6B6 which reacts with small proteoglycans carrying dermatan sulfate side chains. The localization of positive staining in fibrous connective tissues was almost identical with these two procedures.

Antibodies, Monoclonal↗

Effects of beta-D-xylosides on proliferation and matrix formation of adherent fibroblastic cells in mouse bone marrow culture.

Mouse bone marrow cells were seeded on small pieces of cover glasses placed in culture dishes, and after 3 days, the pieces of glass to which only small spindle cells adhered were transferred to another dish containing fresh medium. The adherent small spindle cells proliferated and some of them became large polygonal cells with abundant cytoplasm. When phenyl beta-D-thioxyloside (0.5 mM), an artificial initiator of chondroitin sulfate chain synthesis, was added to the culture medium, the cells showed a marked increase in number as compared to controls, with conversion of about 35% of the cells to large size cells. Immunohistochemical staining with monoclonal antibodies showed that the intercellular matrix of adherent cells consists mainly of a large proteglylcan with chondroitin 6-sulfate side chains. By histochemical analysis, the amount of chondroitin sulfate was shown to be greater in the intercellular matrices of xyloside-treated groups than those of control cultures. The amount of chondroitin sulfate in the growth medium of the adherent cells, as measured by uronic acid analysis, was also significantly increased by treatment with phenyl beta-D-thioxyloside compared with controls.

Animals↗

Prostaglandin-E-producing hepatocellular carcinoma with hypercalcemia.

An autopsy case of prostaglandin E-producing hepatocellular carcinoma with hypercalcemia is presented in this article. A 72-year-old man showed high serum calcium levels (14.2 to 17.3 mg/100 ml) and hypophosphatemia. The plasma level of immunoreactive parathyroid hormone was below the normal range. Administration of oral indomethacin 50 mg daily was effective in decreasing the serum calcium concentration. However, this effect lasted only 5 days, after which it returned to pretreatment levels. The patient died in a hypercalcemic coma. By an autopsy, hepatocellular carcinoma was found in the right lobe of the liver. However, no obvious bone metastases nor abnormalities in the parathyroid glands were detected. The immunoreactive prostaglandin E level assayed in the neoplastic tissue (2278 ng/g) was significantly high when compared with level in the nonneoplastic liver tissue (194 ng/g). The production of prostaglandin E by the tumor itself appears to be the most likely mechanism for the hypercalcemia in this patient.

Aged↗

Case of mixed connective tissue disease associated with autoimmune hepatitis.

A 56-year-old female with mixed connective tissue disease (MCTD) who developed autoimmune hepatitis is described. Hepatitis was controlled effectively by the corticosteroid therapy. Biopsy of the liver revealed swelling and hydropic degeneration of hepatocytes, accompanied by Councilman's body formation and focal necrosis. These histological findings differ from those in three previously described cases. A relationship between MCTD and liver involvement appears possible.

Autoimmune Diseases↗

Differences of liver membrane antibody frequency in alcoholic liver disease. Detection of IgG and IgA classes using radioimmunoassay.

The presence of liver membrane antibody in IgG and IgA was investigated by radioimmunoassay using isolated rabbit hepatocytes as target cells. This technique was more sensitive than the immunofluorescent method. IgG liver membrane antibodies were positive in 24% of patients with alcoholic liver disease. IgA liver membrane antibodies were detected in 58% of patients with alcoholic liver disease, whereas they were detected only in 21% of those with nonalcoholic liver disease, except for cases of autoimmune chronic active hepatitis. In alcoholic liver disease, IgA liver membrane antibodies were detected at a high frequency in a group of patients with alcoholic hepatitis and active cirrhosis (94%) as compared with that of fatty liver, hepatic fibrosis, and inactive cirrhosis (42%). These results suggest that alcoholic liver disease is characterized in part by a humoral immune response of IgA liver membrane antibodies.

Cell Membrane↗

Extracellular matrix of cultivated, poorly differentiated human gastric adenocarcinoma cells promotes attachment and spreading of mesenchymal cells.

To clarify interactions between carcinoma and mesenchymal cells, we examined the extracellular matrix-substance remaining on culture dishes after confluent growths of gastric carcinoma cells were removed with EDTA. The matrix synthesized by poorly differentiated adenocarcinoma cells (cell lines KATO-III and MKN-45) cultivated in serum-free medium has a fibroblast (cell line WI38)-attachment activity, which is not detected in the matrix synthesized by a well differentiated adenocarcinoma (cell line MKN-28). This activity was not observed in KATO-III-matrix extracted with 6 M urea, but could be detected in a 1% SDS extract from the remaining matrix on the culture dishes after 6 M urea extraction. The activity was abolished by treatment with pronase (16 micrograms/ml), trypsin (0.005%) or alkali, but was unaffected by collagenase (80 micrograms/ml, 4 h) or chondroitinase ABC (1 U ml, 1 h). It is conceivable that the fibroblast-attachment activity of the matrix produced by poorly differentiated adenocarcinoma cells is related to the proliferation of interstitial connective tissue in vivo.

Adenocarcinoma↗

Immunological mechanisms of corticosteroid therapy in chronic active hepatitis: analysis of peripheral blood suppressor T-cell and interleukin 2 activities.

To investigate the immunological mechanisms underlying corticosteroid therapy in chronic active hepatitis (CAH), in vitro effects of prednisolone on suppressor T-cell and interleukin 2 (IL-2) activities were examined in six corticosteroid therapy-effective and six therapy-ineffective patients with CAH prior to the therapy. Whereas low suppressor T-cell activity and decreased response to IL-2 in T cells were found in the corticosteroid therapy-effective group, these reductions recovered to the normal range when the activity or response was tested in the presence of prednisolone (1 and 10 micrograms/ml). Corresponding with these recoveries, suppressor T-cell activity arrived at normal values after corticosteroid therapy for 8 weeks. By contrast, in the corticosteroid-ineffective group, no apparent effects of prednisolone on suppressor T-cell activity and the response to IL-2 were observed. The relationship between the clinical effect of corticosteroid therapy and in vitro improvement in suppressor T-cell activity or in the response to IL-2 by prednisolone suggests that, in CAH, the corticosteroid effect is likely to be due to an immunomodulation in T-cell function.

Female↗

Characteristics of "embryoid body" in human gonadal germ cell tumors.

The characteristics of so-called "embryoid body" appearing in gonadal germ cell tumors were studied histologically and immunohistochemically on serial sections of three cases (one ovary and two testes). The embryoid bodies were usually observed to be contiguous with immature or mature intestinal ducts, hepatic nests, or epidermal cell nests on serial sections, though they appeared to be isolated in one section. The "amniotic cavity"-like structure of embryoid body was continuous with intestinal duct, and rarely with squamous cell nests, while the "yolk sac" was continuous with hepatic tissue. In these immature or mature structures, differentiation was always found independently of "disc," and portions of "ectoderm" and "endoderm" remained less differentiated in comparison with others. These findings were in contrast with a normal embryo in which immature and/or mature structures are derived from the embryonic disc. The amniotic cavity connected frequently with yolk sac. From the present results, the embryoid body is not considered to be a real or teratomatous embryo, but only a product during a divergent differentiation into intestine and liver from the plastic epithelium, which seems to be derived from an embryonic gut.

Adult↗

Immunohistochemical localization of chondroitin sulphate and dermatan sulphate proteoglycans in tumour tissues.

Immunohistochemical localization of chondroitin sulphate and dermatan sulphate proteoglycans (PGs) was observed in 70 tumour tissues, using monoclonal antibodies 9A-2 and 3B-3 raised against core molecules obtained from chondroitin sulphate PG by chondroitinase ABC-treatment. They recognize a stub of delta Di-4S and delta Di-6S binding to core protein via a linkage tetrasaccharide, respectively. The antibody 6B6 raised against dermatan sulphate PG obtained from an ovarian fibroma capsule in our laboratory was also used. The interstitial fibrous elements, so-called 'specific stroma' within the cancer cell nests contained chondroitin 4-sulphate PG as revealed with 9A-2, whereas the surrounding connective tissue and the preexisting fibrous connective tissue involved in the tumour growth consisted of dermatan sulphate PG with a considerable amount of chondroitin 4-sulphate PG. Chondroitin 6-sulphate PG as revealed with 3B-3 was located in the connective tissue proliferating from blood vessels and muscle tissue in association with the invasive growth of tumour cells. Chondroitin 6-sulphate PG was also observed in the basement membrane components of some tumours. In non-epithelial tumours (fibrogenic, chondrogenic, osteogenic and neurogenic tumours), chondroitin 4-sulphate was in fibrous portions. When collagenization and hyalinization progressed, dermatan sulphate PG was observed to increase in quantity.

Aggrecans↗

Immunohistochemical studies of DMBA-induced rat mammary tumors.

In order to clarify the biological characteristics of rat mammary tumors induced by 7,12-dimethylbenz-[a]-anthracene (DMBA), histochemical and immunohistochemical studies were performed. Two types of luminal spaces were observed within the tumor. In one type, the lumen was surrounded by eosinophilic columnar cells which were strongly reactive for soybean agglutinin (SBA) but weakly stained with keratin antibodies. In the luminal spaces, substances positive for PAS, dialyzed iron ferrocyanide or alcian blue and resistant to mucopolysaccharidase were occasionally observed. Ultrastructurally, the luminal surface was characterized by the presence of microvilli and tight junctions. In the other type, the lumen was often found in highly cellular foci and surrounded by pale, polygonal or elongated cells which were weakly stained with keratin antibodies but not SBA. The luminal spaces presented a peculiar structure filled mainly with mucoid substances sensitive to hyaluronidase, chondroitinase ABC and heparitinase, and the inner surface of the spaces was surrounded by basement membrane components: laminin, fibronectin and type IV collagen. The results of the present study therefore showed that DMBA-induced mammary tumor consists, partly, of a structure resembling human adenoid cystic carcinoma.

9,10-Dimethyl-1,2-benzanthracene↗

Primary role of hyperkalemia in the acidosis of hyporeninemic hypoaldosteronism.

A 65-year-old woman with mild renal insufficiency had persistent hyperkalemia and hyperchloremic acidosis. Her plasma aldosterone level was relatively low for her hyperkalemia, and her urine pH was low. Fludrocortisone acetate administration corrected both hyperkalemia and acidosis by increasing urinary excretion of potassium and net acid, implicating deficient mineralocorticoid activity in the distal renal tubule in this patient. During this medication urinary ammonium excretion increased, but urine pH remained low, so that urinary titratable acid excretion did not decrease. On the other hand, correction of hyperkalemia by administration of a potassium-calcium exchange resin alone also resolved the acidosis by increasing urinary ammonium excretion. This increment exceeded the decrement of urinary titratable acid excretion, which was caused by raised urine pH secondary to increased urinary ammonium excretion, and resulted in increase of net acid excretion. Thus, in this patient, hyperkalemia appears to be a decisive causative factor in the acidosis, with deficient mineralocorticoid effect only contributing in part to the reduction of net acid excretion and the acidosis.

Acidosis, Renal Tubular↗

Production and characterization of monoclonal antibody to dermatan sulfate proteoglycan.

We purified dermatan sulfate proteoglycan (PG) from the capsule of human ovarian fibroma for use as an immunogen. A monoclonal antibody, designated 6B6, was produced which reacts to the intact molecule of dermatan sulfate PG and the chondroitinase AC-treated core molecule on Western-blotted nitrocellulose membrane. Localization of materials showing crossreactivity to this antibody was studied in human tissues by indirect immunohistochemistry. The interstitial elements of almost all tissues examined were positive for the antibody: dermis, submucosal layer of digestive tract, perichondral layer, perivascular connective tissue, perineurium, adventitia of aorta, vessel wall of vein, pleura, and fibrous capsule of kidney and liver. Positive staining was also observed in fibrous elements at post-necrotic foci of cardiac muscle and pancreas, and at atherosclerotic lesions of aorta. The distribution of the antigen, core protein of the dermatan sulfate PG, revealed with 6B6 was compared to that of the dermatan sulfate side chain, which was demonstrated with antibody 9A-2 (Couchman et al.: Nature 307:650, 1984) after treatment with chondroitin sulfate B-lyase. The distribution of both antigens, core protein, and dermatan sulfate side chains showed the same pattern, with minor exceptions. The antibody 6B6 will be a useful tool to study the immunohistochemical localization of dermatan sulfate PG.

Adult↗

The effects of antianginal drugs on left ventricular function in patients with effort angina pectoris. Comparison among isosorbide dinitrate, nifedipine and propranolol by PANOVA.

To study the acute effects of ISDN, nifedipine, propranolol and placebo on cardiac function in patients with myocardial ischemia and to characterize their hemodynamic effects by PANOVA, we repetitively performed exercise radionuclide angiography (RNA) following random assignment of each drug in 20 patients with effort angina pectoris. We obtained exercise response curves of hemodynamic parameters determined by RNA. ANOVA was performed to analyze the sizes (average height) of those response curves, and PANOVA (principal component analysis, PCA, combined with ANOVA) to analyze differences in the profiles (patterns) of the curves. By conventional analysis of variance followed by a Scheffé type multiple comparison, end-diastolic volume after ISDN, which was significantly smaller than those after the other drugs at rest (p less than 0.01), was similar to those after nifedipine and propranolol during exercise (96.4 +/- 4.6 ml/m2 vs. 94.8 +/- 5.1 ml/m2 and 97.1 +/- 4.9 ml/m2, respectively). Systemic vascular resistance after nifedipine, which was also significantly lower than those after the other drugs at rest (p less than 0.05), was not different from that after placebo during exercise (16.9 +/- 1.1 units vs. 18.7 +/- 1.3 units). Thus, this analysis was considered insufficient to fully differentiate the characteristics of each drug. By PANOVA, the profiles of LVEF with these three antianginal drugs were similar, and significantly differentiated from that of placebo (p less than 0.05). This indicated that the antianginal effect could be represented by the profiles of the response curves of LVEF, using PANOVA. Evaluating the underlying hemodynamic mechanisms of these drugs by PANOVA, ISDN was significantly differentiated from nifedipine and propranolol by the profile of end-diastolic volume (p less than 0.05). The characteristics of nifedipine were clearly demonstrated by the size and profile of systemic vascular resistance, and those of propranolol were also differentiated by the size and profile of the double product and P-V index. Hence, it is concluded that with the aid of PANOVA, the changes in hemodynamic parameters during ischemia can be evaluated in a manner that is highly effective in differentiating the characteristics of the effects of antianginal drugs in patients with angina pectoris.

Aged↗

Serial analysis of spontaneous and induced ventricular arrhythmias in a canine model of myocardial infarction.

To study the time course of spontaneous and induced ventricular arrhythmias after myocardial infarction (MI), 20 dogs underwent ligation of the left anterior descending coronary artery and temporary occlusion and reperfusion of the obtuse marginal branch. There were 5 early deaths (less than 24 hours) due to spontaneous ventricular fibrillation (VF). All 15 survivors exhibited spontaneous ventricular tachycardia (VT) up to day 3 with the shortest cycle length occurring at 17 hours after MI (232 +/- 11 msec: mean +/- SEM). The grade of arrhythmia complexity was decreased after day 4 compared to day 1 (p = 0.049), and the number of ventricular premature complexes was reduced after day 6 (1700 +/- 1390/hour) compared to day 1 (9500 +/- 640/hour, p = 0.042). Serial electrophysiologic studies were carried out on days 8, 15, 22, and 29 via an implanted antitachycardia pacemaker using 1 to 3 extrastimuli and rapid ventricular pacing (RVP). On day 8, VT was inducible in 7 dogs (46%), VF in 4 (27%), and 4 dogs (27%) exhibited a negative response. On day 15, 3 more dogs became negative, and all previously negative dogs displayed negative responses. From day 15, the inducibility of VT/VF remained "constant" using RVP. However, inducibility by triple extrastimuli declined week by week until day 29. Stepwise logistic regression analysis of 20 variables selected the mass of the MI as the only independent predictor of inducible VT/VF by multiple extrastimuli and RVP after day 15 (p = 0.049). Thus significant time- and mode-dependent changes in inducibility of VT/VF occur during the early phase after MI.

Animals↗

The use of evoked endocardial response for assessment of antiarrhythmic drug effects on myocardium.

The technique "asymmetric biphasic stimulation" which paces the heart and neutralizes the post-stimulus polarization at the electrode-tissue interface allows for the recording of the entire evoked endocardial response via a single electrode for both pacing and recording. Using this system the effects of antiarrhythmic drugs, procainamide and N-acetylprocainamide, on the myocardium were studied in 20 dogs. Before and during the five-step drug infusion, the evoked endocardial responses were recorded during bipolar and unipolar at the rates of 120, 150 and 200/min. The plasma concentration of the procainamide ranged from 1.7 to 32.5 mg/l and that of N-acetylprocainamide ranged from 8.1 to 116.1 mg/l. Procainamide significantly prolonged both the depolarization duration and the repolarization duration at a low plasma concentration (Class I antiarrhythmic drug property). N-acetylprocainamide significantly prolonged the repolarization duration at a low plasma concentration, while the depolarization duration was not significantly changed at a low or therapeutic plasma concentration (Class III antiarrhythmic drug property). The prolongation of the depolarization duration by procainamide and N-acetylprocainamide was rate-dependent; the faster the rate the greater the prolongation. This simple and accurate assessment of the antiarrhythmic drug effects on the myocardium may provide a future means for the pharmacologic antiarrhythmic therapy.

Acecainide↗