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T Tani

Publications and source records attributed to T Tani.

At least 217 records · Page 12Linked to original sources
PubMed1995

Angiotensin II type-1 receptor antagonist as well as angiotensin converying enzyme inhibitor attenuates the development of heart failure in aortocaval fistula rats.

OBJECTIVES: We investigated the effect of chronic administration of an angiotensin II type-1 receptor antagonist in the development of heart failure due to volume overload in rats. METHODS: Aortocaval fistula (AVF), a model of volume overloaded heart failure, was induced in rats by our newly developed technique using a simple and rapid 18-gauge needle multipuncture. After 3 weeks of oral administration of an angiotensin II receptor antagonist TCV-116, 1 mg/kg per day, we evaluated the hemodynamics, heart weight, and degree of left ventricular dilatation. We also compared the effect of TCV-116 with that of an angiotensin-converting enzyme inhibitor delapril, 1 g/L in drinking water. RESULTS: AVF heart failure produced by our technique exhibited significant increases in the left ventricular end-diastolic pressure (LVEDP) (12 = 1 vs 4 +/- 1 mmHg, p < 0.05), right atrial pressure (RAP) (5.0 +/- 0.6 vs 1.0 +/- 0.4 mmHg, p < 0.05), right ventricular systolic pressure (RVSP) (58 +/- 6 vs 33 +/- 1 mmHg, p < 0.05), left ventricular weight (LVW) (3.00 +/- 0.13 vs 2.09 +/- 0.04 g/kg BW, p < 0.05), right ventricular weight (RVW) (0.93 +/- 0.05 vs 0.59 +/- 0.01 g/kg BW, p < 0.05), and left ventricular end-diastolic volume index (LVEDVI) (2.55 +/- 0.14 vs 0.80 +/- 0.12 ml/kg BW, p < 0.05) as compared with these values in sham-operated rats. There were no differences in shunt ratio between untreated and TCV-116- and delapril-treated AVF groups. TCV-116 improved these hemodynamics, as did delapril (TCV-116 vs delapril: LVEDP 8 +/- 1 vs 8 +/- 1, RAP: 3.8 +/- 0.6 vs 2.3 +/- 1.4, RASP: 50 +/- 2 vs 46 +/- 3, LVW: 2.53 +/- 0.11 vs 2.52 +/- 0.15, RVW: 0.80 +/- 0.04 vs 0.77 +/- 0.06, LVEDVI: 1.67 +/- 0.15 vs 1.70 +/- 0.17). CONCLUSION: These results suggest that AVF rats with volume overload produced by a new multipuncture method exhibit both right- and left-side heart failure. Angiotensin II type-1 receptor antagonist as well as angiotensin converting enzyme inhibitor attenuate the development of this type of heart failure in rats.

Analysis of Variance↗
PubMed1995

The response of serum and hepatic lipids and the aortic wall to different levels of dietary cholesterol: a comparative study between hyperlipidemia-and- atherosclerosis-prone quail and commercially available quail.

A hyperlipidemia-and-atherosclerosis-prone (LAP) quail model was developed by dietary cholesterol feeding through genetic selection of commercially available (CA) Japanese quail. The response of serum lipids and the aortic wall to dietary cholesterol feeding was compared in CA and LAP quails. Ten groups were fed a combination diet with different levels of cholesterol and corn oil for 12 weeks. In CA quail, dietary feeding of cholesterol only failed to induce significant hypercholesterolemia or atherosclerotic lesion. The respective optimal dietary levels of cholesterol and corn oil to induce hyperlipidemia and atherosclerotic lesion, were 2% and 15%, respectively. Ad-libitum feeding of only 0.5% cholesterol without corn oil induced significant hypercholesterolemia and aortic atherosclerosis in LAP quail. The main proliferating cellular component of the aortic atherosclerotic lesion was phenotypically transformed fibroblasts from medial fibroblasts. These results suggest that the LAP quail is a useful animal model for the study of atherosclerosis.

Animals↗
PubMed1995

Differential expression of laminin chains and their integrin receptors in human gastric mucosa.

The proliferating cells of the gastric mucosa are found among the pit and mucous neck cells. These cells migrate upward to renew the surface epithelium and downward to restitute the glandular cells. As the epithelial basement membranes (BMs) function as substrate for cell adhesion and migration as well as signals for their differentiation, we studied, by indirect immunofluorescence microscopy, the distribution of different laminin chains and their integrin receptors in adult human stomach. The immunoreactivity for laminin alpha 2 chain localized to the BMs of glands and the lower parts of the gastric pits whereas the laminin alpha 3 chain (laminin-5/kalinin) immunoreactivity was strictly confined to BMs underneath the surface epithelium and the upper parts of the pits. Proliferating mucosal epithelial cells, identified by Ki-67 antibodies, were confined to the areas containing both alpha 2 and alpha 3 laminin chains. The alpha 1, beta 1, and gamma 1 laminin chains were found in all BMs of the mucosa whereas the beta 2 chain was prominent in mucosal blood vessels and also detectable in some glands. Among the laminin integrin receptors, the alpha 3 and beta 4 subunits were seen to be expressed in cells along the BMs with the alpha 3 laminin chain. The alpha 6 integrin, on the other hand, was seen in all gastric epithelia. The present results demonstrate that in the adult human stomach laminin alpha 2 and alpha 3 chains show zonal distribution in BM underlying gastric mucosal epithelium whereas other laminin chains show a more general distribution.

Adult↗
PubMed1995

[Endotoxin eliminating therapy in patients with severe sepsis--direct hemoperfusion using polymyxin B immobilized fiber column].

BACKGROUND AND METHODS: PMX is a blood purifier containing chemically immobilized polymyxin B fiber (PMX-F). To evaluate its effectiveness on the severe septic human, direct hemoperfusion (DHP) using a PMX-F was performed for 2 hours. The changes in various circulatory parameters, symptoms of septic shock, and blood endotoxin concentration and the survival rate, were evaluated. RESULTS: DHP was performed 61 times in 42 patients, of whom 38 had septic MOF, 25 with gram-negative bacterial infection. At the initiation of this treatment, 33 patients were receiving vasoactive agents, and 36 were under artificial ventilation via endotracheal intubation. The mean septic severity score (SSS) in all patients was about 46.6. Twenty-two of the 42 survived. The endotoxin concentration (mean +/- S.E.; pg/ml) was 85.0 +/- 27.2 immediately before treatment but significantly decreased to 57.5 +/- 28.4 after treatment (n = 50) and to 28.2 +/- 4.4 on the next day (n = 23) (p < 0.01). The endotoxin concentrations at the inlet and outlet of the PMX also significantly decreased 30 minutes after the initiation of DHP. Circulatory parameters, BP, CI, SVR and Vo2I demonstrated significant improvement. Body temperature also showed the same results. The removal of endotoxin in the blood using PMX was effective for severe sepsis or septic MOF. Various symptoms due to endotoxin was alleviated after this treatment.

Adolescent↗
PubMed1995

[Effects of beraprost sodium (a PGI2 derivative) on chronic hypoxic pulmonary hypertension in the rat].

To determine whether beraprost sodium (beraprost) can cause pulmonary vasodilation in chronic hypoxic pulmonary hypertension, we measured the hemodynamic effects of intravenous beraprost, a stable and orally active agent with a PGI2-like structure, in chronic hypoxic (H) and normoxic (N) rats. During anesthesia baseline pulmonary artery pressure (PAP) was 32.0 +/- 1.0 in H rats and 18.0 +/- 0.4 mmHg in N rats. Intravenous beraprost (20 micrograms/kg) elicited acute pulmonary vasodilation by 17.7 +/- 4.6% (5.6 +/- 1.4 mmHg) in H rats and by 16.8 +/- 2.1% (3.0 +/- 0.6 mmHg) in N rats, which indicates that the relative degree of acute pulmonary vasodilation caused by beraprost was similar in H and N rats. Thirty minutes after the drug was injected, PAP had not returned to baseline levels in either H or N rats, and it was lower in H rats (90 +/- 2%) than in N rats (95 +/- 2%). Lungs were isolated and perfused with saline, and those from H rats and N rats showed similar pulmonary vasodilator responses to 2 and 20 micrograms/kg beraprost. These results indicate that although beraprost caused a similar degree of acute pulmonary vasodilation in H and N rats, in H rats the response lasted longer. Thus PGI2 derivatives may be useful as vasodilators in some patients with primary and secondary pulmonary hypertension.

Animals↗
PubMed1995

Prognostic significance of nucleolar organizer regions in hepatocellular carcinoma.

It has been suggested that the number of argyrophilic nucleolar organizer regions (AgNORs) correlates with cellular activity and the aggressiveness of malignancy. The mean number of AgNORs per nucleus may, therefore, be a prognostic factor for hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the prognostic significance of the number of AgNORs in HCC. The silver-staining technique was applied to surgically resected specimens to indicate AgNORs. Eighty-nine of the specimens were of HCC, 23 were of normal liver adjacent to HCC, and 32 were of cirrhotic liver adjacent to HCC. The number of AgNORs of HCC (mean +/- SD, 3.26 +/- 1.23) was significantly higher than those of normal liver (1.37 +/- 0.13) and cirrhotic liver (1.49 +/- 0.14). The number of AgNORs was significantly correlated with serum alpha-fetoprotein level, tumor size, portal vein invasion, and Edmondson-Steiner histological grade. In patients undergoing curative resection, the survival rate of those with a high number (> 3.04) of AgNORs was significantly worse than that of those with a low number (< or = 3.04) of AgNORs. Multivariate analysis showed that the number of AgNORs was a significant prognostic indicator in patients without portal vein invasion, and portal vein invasion was the only significant variable when all patients undergoing curative resection were assessed together. The results of this study suggest that the number of AgNORs is useful as an indicator of the grade of malignancy and as a predictor of the prognosis of patients with HCC who do not have portal vein involvement.

Adolescent↗
PubMed1994

Lymphangioma of the duodenum: report of a case.

A case of lymphangioma of the duodenum with a successful preoperative diagnosis is reported herein. A 76-year-old man who complained of tarry stool was found to have a hemorrhagic polypoid tumor in the third portion of the duodenum. The tumor was diagnosed histologically as cavernous lymphangioma by endoscopic biopsy. Since such a tumor is essentially benign, a partial resection of the duodenum including the tumor was performed. Therefore, an endoscopic biopsy seems to be valuable in the diagnosis of duodenal lymphangioma.

Aged↗
PubMed1994

Cardioprotective effect of the angiotensin II type 1 receptor antagonist TCV-116 on ischemia-reperfusion injury.

We investigated the protective effect of angiotensin II (Ang II) type 1 receptor antagonist on myocardial ischemia-reperfusion injury and the role of exogenous Ang II to this injury in perfused hearts. We orally administered TCV-116 (Ang II type 1 receptor antagonist) and delapril (angiotensin converting enzyme inhibitor) to Wistar rats for 1 week and measured the immunoreactive cardiac Ang II. Immunoreactive cardiac Ang II (pg/gm tissue) was 14.3 +/- 2.0 in control group, 11.8 +/- 0.8 in TCV-116-treated group, and 7.3 +/- 0.6 in delapril-treated group (p < 0.05 compared to TCV-116-treated group; p < 0.01 compared to control group). The 15 hearts (five rats in each group) were perfused by a langendorff method and global ischemia was maintained for 30 min. Both TCV-116 and delapril were found to improve postischemic cardiac function and decrease reperfusion creatine kinase (CK) release. Ang II injection before ischemia worsened postischemic cardiac function and increased reperfusion CK release. Only TCV-116 prevented this injury. These data indicated that TCV-116 Ang II type 1 receptor antagonist was effective against myocardial ischemia-reperfusion injury, and exogenous Ang II accelerated this injury through Ang II type 1 receptor.

Angiotensin II↗
PubMed1994

Treatment of sepsis by extracorporeal elimination of endotoxin using polymyxin B-immobilized fiber.

Despite the use of potent antibiotics and intensive supportive care, mortality remains high among septic shock patients, especially those with endotoxemia. To remove endotoxin directly from the blood, a material consisting of polymyxin B that is immobilized on fibers (PMX-F) and that can selectively detoxify endotoxin was developed. In a preliminary clinical study, 16 patients with septic multiple organ failure were treated with direct hemoperfusion using a PMX-F column. This therapy significantly decreased the endotoxin level from 76 pg/mL to 21 pg/mL after 2 hours of direct hemoperfusion. The hyperdynamic state of the cardiac index, which is a characteristic of endotoxic shock, returned to normal levels after treatment. In septic shock patients with a systolic pressure of less than 100 mm Hg, the systolic arterial pressure increased significantly from the pretreatment level. The alleviation of fever caused by this therapy continued until the day after treatment. Of the 16 patients who underwent this therapy, 9 were alive 2 weeks after this therapy and 7 patients were discharged from the hospital alive. Hemoperfusion with PMX may be an effective treatment for sepsis and septic shock.

Biocompatible Materials↗
PubMed1994

Ameliorative effect of dietary probucol on polychlorinated biphenyls-induced hypercholesterolemia and lipid peroxidation in the rat.

The hypocholesterolemic and antioxidant activities of probucol (PB) were examined in rats which were fed for 10 days with diets supplemented with or without 0.02% polychlorinated biphenyls (PCB). Dietary intake of PCB caused multiple effects on lipid metabolism, such as increased levels of both serum and HDL cholesterol, and increased TBA-reactive substances (TBARS), in hepatic subcellular fractions. PB 1% in comparison with either control or alpha-tocopherol (Toc) 0.1%, reduced the serum cholesterol levels in normolipemic as well as in PCB-induced hypercholesterolemic rats. In addition, this drug ameliorated the elevated TBARS induced by PCB in the hepatic subcellular fractions, although less antioxidant activity was noted in rats fed PB than in those fed Toc. The microsomes isolated from various groups were incubated for 2h at 37 degrees C in the presence or the absence of ferrous iron in vitro; microsomes from the PB-fed rats were as much resistant against lipid peroxidation in ferrous-free incubation medium as were those from Toc-fed rats, while in the presence of ferrous iron there was a higher antioxidant effect on lipid peroxidation in the latter fraction than in the former. HPLC analyses showed that less PB than Toc was incorporated into the hepatic subcellular fractions, suggesting that the concentration of antioxidants in hepatic subcellular fractions determine the extent of lipid peroxidation in situ. These results suggest that the administration of PB is an effective approach for the treatment of both hypercholesterolemia and elevated lipid peroxidation while Toc ameliorates only an elevated lipid peroxidation.

Animals↗
PubMed1994

Role of Ca2+ in the binding of phospholipase A2 with a monomeric substrate and with its amide-type analog.

Effects of Ca2+ on the kinetic parameters for the hydrolysis of monodispersed 1,2-dihexanoyl-sn-glycero-3-phosphorylcholine (diC6PC), catalyzed by Group I phospholipases A2 (PLA2s) from Pseudechis australis, Naja naja atra, and bovine pancreas and by Group II enzymes from Vipera russelli russelli, Agkistrodon halys blomhoffii, and Trimeresurus flavoviridis, were studied by the pH-stat assay method at 25 degrees C, pH 7.5-8.2, and an ionic strength of 0.1 or 0.2 in the absence or presence of an amide-type substrate analog, 2-dodecanoyl-amino-1-hexanol-phosphoglycol. The binding of genuine substrate to the Group II enzymes and that of its analog to the Groups I and II enzymes were markedly facilitated by the binding of Ca2+ to the enzymes. On the other hand, the binding of genuine substrate to the Group I enzymes was found to be independent of the Ca2+ binding. The former result suggests that the structures of the Group II enzyme-genuine substrate complexes and both types of enzyme-analog complexes are generally stabilized by the Ca2+ binding, whereas the latter indicates that the structures of the Group I enzyme-genuine substrate complexes are already similar to those of their Ca2+ complexes and that, therefore, these enzyme-substrate interactions are independent of the Ca2+ binding.

Amides↗
PubMed1994

The deleterious effects of exogenous angiotensin I and angiotensin II on myocardial ischemia-reperfusion injury.

Angiotensin II is well known to have a cardiotoxic effects. However, it is still unclear whether exogenous angiotensin I or angiotensin II has a deleterious effect on myocardial ischemia-reperfusion injury. To examine this deleterious effects, we administered angiotensin I and angiotensin II to perfused hearts before ischemia, and measured creatine kinase (CK) release and cardiac function during subsequent reperfusion. Wistar Kyoto rats were used and the hearts were perfused by the Langendorff technique at a constant flow (10 ml/min). Seven hearts were perfused for 20 min and then subjected to 15 min of global ischemia (Control). In the experimental groups, during the 5 min before ischemia, we administered 100 ng/ml angiotensin I (Ang I; n = 9), 1 microgram/ml enalaprilat (ACEI; n = 5), both agents (ACEI + Ang I) (n = 6), or 10 ng/ml angiotensin II (Ang II; n = 6). The perfusates were then sampled to measure angiotensin II. After 15 min of ischemia, the hearts were reperfused with control perfusate. Throughout the 20 min of reperfusion, the effluent was collected to measure cumulative CK release. Angiotensin I increased coronary perfusion pressure (CPP) by 32 +/- 4 mmHg, however, the angiotension converting enzyme inhibitor inhibited the increase of CPP by angiotension I (11 +/- 1 mmHg) (p < 0.01). The contents of angiotensin II in the effluent in Ang I and Ang I + ACEI were 11.5 +/- 1.9 ng/ml and 4.0 +/- 0.5 ng/ml (p < 0.01). After 20 min of reperfusion, the left ventricular developed pressure was unchanged in all of the groups. CPP was also unchanged by ischemia in all of the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin I↗
PubMed1994

End-to-end duodenojejunal bypass for unresectable periampullary carcinoma.

Palliative operation plays an important part in the treatment of periampullary carcinoma. However, gastric bypass such as the widely practiced side-to-side gastrojejunostomy frequently fails to provide adequate drainage. Here we attempted to fashion an end-to-end duodenojejunostomy in the hope of establishing physiological continuity of the stomach and duodenum. Biliary bypass with side-to-side choledochojejunostomy is performed simultaneously. Eight patients underwent this surgery. In seven of these, radical resection proved to be impossible, and in one the duodeno-biliary decompression was attempted before the radical operation. Early results were satisfactory in all patients. They began to eat liquid meals within a week, and were discharged uneventfully within the third postoperative week, when they were able to eat a regular diet. No ulcer developed in any of the patients. Plasma gastrin levels following a test meal was significantly lower after the operation, but plasma CCK-N and GIP levels showed no statistical difference prior to and after surgery. This duodenojejunal bypass is recommended as a means of improving the quality of the remaining life of the patients.

Aged↗
PubMed1994

Effects of dietary fat levels on the absorption and tissue accumulation of probucol in the rat.

The effects of dietary fat level on the absorption and tissue accumulation of probucol (PB, CAS 23288-49-5) were studied in male Wistar rats. Addition of 1% PB (w/w) to the diets as compared to the diets without an addition (P) resulted in a decrease in the concentration of both serum and high-density lipoprotein (HDL) cholesterol as well as TBA-reactive substances (TBARS), without influencing food intake or growth. When rats were fed with the PB diet, the apparent intestinal absorption of PB was 7.9%, while the serum PB level was 5 micrograms/ml. The tissue distribution of PB, when expressed per g of tissue, was highest in the adrenal glands, followed by the liver, heart, epididymal adipose tissues, kidneys, lung, spleen, and testes. The addition of 10% olive oil (PBO) to the PB diet (w/w) appeared to double the PB diet-induced increase in apparent intestinal absorption and the serum concentration of PB. Furthermore, compared with the PB diet, the PBO diet caused 3- to 4-fold higher accumulation of PB in the liver and its subcellular fractions and 2-fold higher accumulation in the spleen. However, there was no further accumulation of the drug in the heart, kidneys, lungs, and testes. Incorporation of the drugs into adipose tissues was significantly lower with the PBO diet than with the PB diet. These results suggest that dietary manipulation leads to changes in the intestinal absorption and serum level of PB.

Animals↗
PubMed1994

The state of recurrence and the role of hepatectomy in hepatocellular carcinoma.

The subjects involved in the present study were 113 patients with hepatocellular carcinomas who had undergone hepatectomy in our hospital during the past 10 years. During the surveillance, 79 of the 113 patients (69.9%) had recurrence in the residual liver. The cumulative non-recurrence rate at 2 and 5 years was 48.4% and 18.1%, respectively and the cumulative survival rate at 2 and 5 years was 83.8% and 47.5%, respectively. The recurrence in the residual liver tended to occur in the group with the larger tumor size, in the single nodular surrounding proliferative types and in the aneuploid types. There were no differences in the recurrence rate and state relating to the operative procedure. To improve the prognosis of hepatocellular carcinoma, it is necessary to consider the hepatic functional reserve after hepatectomy, and to make plans for multidisciplinary therapy, including such further treatment as transcatheter arterial embolization, infusion chemotherapy and preoperative percutaneous ethanol injection.

Adult↗