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Biomedical subjects

I Ogata

Publications and source records attributed to I Ogata.

At least 73 records · Page 4Linked to original sources
PubMed1988

Exchange blood transfusion for acute hepatic failure: its limited availability depending on the type of injury in rats.

The efficacy of exchange blood transfusion for acute hepatic failure was evaluated using rats. Rats receiving a dose of carbon tetrachloride died later than 24 h after dosing. When their blood was replaced with blood from normal rats at 24 h, survival time was prolonged, and hepatic protein synthesis was enhanced at 36 h with improved prothrombin time (PT). Those rats surviving 120 h showed better histological grade of recovery from injury after treatment. In contrast, dimethylnitrosamine (DMN)-intoxicated rats showed no such improvement in survival time or PT. In rats given a nonfatal dose of carbon tetrachloride, serum glutamic-pyruvic transaminase values were five times higher than those in rats given DMN despite similar maximal PT. The benefit of exchange transfusion for acute hepatic failure may differ depending on the mechanism of development in rats. Enhanced hepatic protein synthesis may contribute to its effect.

Acute Disease↗
PubMed1988

Intravascular coagulation in acute liver failure in rats and its treatment with antithrombin III.

Liver damage was induced in rats by injection of dimethylnitrosamine (DMN) or carbon tetrachloride (CCl4). Fibrin clots were observed in the hepatic sinusoids at 12 hours and soluble fibrin monomer complexes were markedly detected at 24 hours only in the rats given DMN. When antithrombin III concentrate was infused at 12 hours there was a dose dependent improvement of the values of serum total bilirubin, SGPT, prothrombin time, peripheral platelet count, and plasma fibrinogen and coagulation factor VIIIC and of the histological degree of liver injury at 24 hours in the DMN group. The CCl4-group showed no such improvement. Intravascular coagulation may complicate the course of certain types of acute liver injury and contribute to its aggravation in rats. Under such circumstances, treatment with antithrombin III concentrate would be beneficial.

Animals↗
PubMed1988

Glucagon and insulin for the treatment of hepatic failure in dimethylnitrosamine-intoxicated rats.

When rats received dimethylnitrosamine every 24 h until death, plus hormone treatment after the first 24 h, the survival was enhanced between 100 and 140 h compared with the control rats, with attenuated derangements of prothrombin time and serum albumin levels at 120 h. In rats given a single dose of dimethylnitrosamine, hepatic DNA synthesis peaked at 48 h. The synthesis was increased after hormone treatment when started immediately, but not when delayed for 24 h. Hormone treatment for 3 days starting 24 h after a single dose of dimethylnitrosamine produced a rapid normalization of decreased hepatic protein content on day 9, although hepatic DNA content was not affected. These results suggest that this treatment is effective for hepatic failure, and the promotion of restoration of liver function is a contributing factor to its effect, in addition to the stimulation of hepatocyte proliferation.

Animals↗
PubMed1988

Contribution of hepatic reticuloendothelial system to glomerular IgA deposition in rat liver injury.

Liver damage was induced in rats by a single dose of dimethylnitrosamine or D-galactosamine. In the dimethylnitrosamine model, marked glomerular IgA deposition occurred between Days 4 and 28, with its peak at Day 14. Serum IgA levels were significantly increased at Days 2 and 4, then gradually decreased, and normalized at Day 14. In the D-galactosamine model, however, no such deposition was observed, though serum IgA levels similarly increased on Days 2 and 4. IgA content in high molecular weight fraction from serum increased at Day 3 in both models. This increment remained at Day 7 only in the dimethylnitrosamine model, in which carbon clearance from the circulation was significantly decreased at Day 3. These data suggest that dysfunction of the hepatic reticuloendothelial system is a factor contributing to glomerular IgA deposition occurring in liver injury.

Alanine Transaminase↗
PubMed1985

Collagen accumulation can continue with decreased prolyl hydroxylase activity in the liver.

A single dose of dimethylnitrosamine dose-relatedly increased total hepatic hydroxyproline content in rats 14 days after the dosing. In cases of 35 mg/kg of dimethylnitrosamine, it increased rapidly to 1.7 times the normal level within 14 days. This increase persisted thereafter until 84 days. Hepatic collagen prolyl hydroxylase activity was 1.8 times the normal level by the fourth day after the dosing but normalized within 14 days. It decreased further to levels significantly lower than those in normal rats at 28, 56 and 84 days. Serum glutamic pyruvic transaminase activity was about 13 times the normal level at 2 days and normalized after 7 days. On histology, fiber developed in necrotic areas around the central veins after 7 days and remained after 28 days when the necrosis had already disappeared. These results suggest that abnormal collagen can continue to increase in the state of decreased collagen prolyl hydroxylase activity in the liver.

Alanine Transaminase↗
PubMed1985

Transcatheter arterial embolization for hepatocellular carcinoma. Benefits and limitations for unresectable cases with liver cirrhosis evaluated by comparison with other conservative treatments.

Transcatheter arterial embolization (TAE) for unresectable hepatocellular carcinoma (HCC) was performed in cirrhotic patients with nonoccluded main portal trunk and total bilirubin levels less than 5 mg/dl. In 48 patients with tumor response to TAE, its benefit was evaluated by comparing their survival with that in 28 patients after conservative treatments, matched by clinical data. In TAE-treated patients, tumor findings on computerized tomography and angiogram were significantly different between those dying within 3 months and those surviving over 18 months. In cases of tumors occluding the first- or second-order portal branches or occupying more than 20% of the liver, or relatively hypovascular tumors with unclear boundaries, survival was not different between TAE- and non-TAE-treated patients, whereas it was significantly improved by TAE in cases without these findings. These results suggest that TAE is beneficial in cases of unresectable HCC complicating liver cirrhosis, but its benefit is limited under certain conditions.

Adult↗
PubMed1985

Benefit of transcatheter arterial embolization for ruptured hepatocellular carcinoma complicating liver cirrhosis.

In 6 patients with spontaneous rupture of hepatocellular carcinoma complicating liver cirrhosis, but with no occlusion of the main portal trunk, transcatheter arterial embolization was performed within 7 days of the rupture. All 6 patients were thought to be inoperable because of shock state or severe hepatic dysfunction. In all 6 patients, the progressive decrease in the hematocrit ceased soon after the embolization. Five patients survived for 31-168 days after the embolization; 1 patient who developed septicemia died 10 days later. We conclude that transcatheter arterial embolization is beneficial as a procedure of first choice for ruptured hepatocellular carcinoma when the portal blood flow is maintained.

Adult↗
PubMed1985

Collagen prolyl hydroxylase inhibitor and reduced collagen formation in cotton pellet-induced granuloma and skin wound healing in rats.

P-1894B an inhibitor of collagen prolyl hydroxylase was applied topically to cotton pellet-induced granuloma and to skin lesions in rats. The total hydroxyproline content of the granulomata was significantly reduced by this agent. It also reduced the hydroxyproline content in the tissues surrounding skin lesions during the healing process, with delayed diminution in lesion size. These results suggest that collagen prolyl hydroxylase inhibitor P-1894B may be a suitable agent for topical treatment of hypertrophic scar tissue or keloid.

Animals↗
PubMed1985

End-systolic pressure-volume, pressure-length, and stress-strain relations in canine hearts.

End-systolic pressure-volume relationship (ESPVR) of the in situ heart in the dog was measured during changes in contractile state and was compared with end-systolic pressure-length (ESPLR) or stress-strain relationship (ESSSR). Circumferential segmental length and wall thickness at the equator and external long and short axis diameters of the left ventricle (LV) were determined sonomicrometrically, and LV volume was calculated by an ellipsoidal model. Circumferential wall stress at the equator was calculated by a very thin shell model. Contractile state was enhanced by an intravenous infusion of dobutamine and was suppressed by propranolol. ESPVR, ESPLR, and ESSSR were determined during a reduction of arterial pressure by occluding temporarily the inferior caval vein (IVC). ESPVR, ESPLR, and ESSSR during changes in end-systolic pressure from 108 +/- 3 to 71 +/- 2 mmHg were linear, irrespective of inotropic states (r greater than 0.92). Slopes of these relationships increased similarly in case of dobutamine and were reduced after propranolol, yet the extrapolated X-axis intercept of ESPVR, ESPLR, and ESSSR remained unchanged. Thus the slope of ESPVR is unique to the inotropic state, and both ESPLR and ESSSR are useful as a substitute for ESPVR when there is no regional wall motion abnormality.

Animals↗
PubMed1985

Right and left ventricular dysfunction in patients with dilated cardiomyopathy: a study with equilibrium radionuclide ventriculography.

Right and left ventricular function was evaluated in 28 patients with dilated cardiomyopathy to determine whether both ventricular functions were equally impaired in each patient. The ejection fractions of both ventricles were measured using equilibrium radionuclide ventriculography. In 13 patients the left ventricular ejection fraction (LVEF) was lower than the right ventricular ejection fraction (RVEF) by 6% or more, their mean values being 24 +/- 8% (mean +/- SD) and 37 +/- 7%, respectively (group 1). The difference between the LVEF and RVEF was less than 6% in nine patients; LVEF 29 +/- 8% and RVEF 30 +/- 7% (group 2). In six patients the RVEF was lower than the LVEF by 6% or more, and their mean values were 21 +/- 6% and 37 +/- 10%, respectively (group 3). The frequency of ventricular tachycardia, which was determined by the Holter ECG, was significantly higher in group 3 (100%, 6/6) than in the others (group 1 + 2; 41%, 9/22), p less than 0.05. The NYHA functional class correlated well with the LVEF, but not with the RVEF. It was concluded that the left and right ventricular functions are not necessarily equally impaired in patients with dilated cardiomyopathy, and that the difference may correlate with their clinical features.

Adult↗
PubMed1984

End-systolic pressure-length relations during changes in regional contractile state.

End-systolic pressure-length relationship (ESPLR) was examined in the heterogenously contracting heart in open-chest dogs. Regional length was measured sonomicrometrically in the areas of both the left circumflex coronary artery (LCX) and left anterior descending coronary artery (LAD). ESPLR was linear during a transient reduction in arterial pressure following occlusion of the inferior caval vein (IVC). In group 1 (12 dogs), saline as a control condition (Cont) and isoproterenol (Iso, 0.05 microgram/min) to enhance the regional contractile state were infused into the LCX. Percent shortening in the LCX area increased from 13 to 16% (P less than 0.01) in Iso. The slope (Ees) of ESPLR increased from 57 to 71 mmHg/mm (P less than 0.01) in Iso. The extrapolated X-axis intercept (Lo) of ESPLR was unchanged. In the LAD area, Ees and Lo remained constant. In group 2 (13 dogs), lidocaine (1 mg/min, Lid 1; 5 mg/min, Lid 5) was infused into the LCX to induce mild and severe hypokinesis, respectively. Percent shortening in the LCX area was reduced from 14 to 8% (P less than 0.01 vs. Cont) in Lid 1 and 5% (P less than 0.01 vs. Cont, P less than 0.05 vs. Lid 1) in Lid 5. Ees tended to decrease in Lid 1 but to increase in Lid 5 (statistically not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Differential registration of two types of radionuclides on macroautoradiograms for studying coronary circulation: concise communication.

Double-radionuclide autoradiography proved to be feasible using combinations of Tc-99m and I-125, or Tc-99m and C-14. Because of the short half-life of Tc-99m (6 hr), we first registered Tc-99m on x-ray film. Given an adequate Tc-99m:I-125 activity ratio of 20:1, the exposure duration for Tc-99m was still too short for I-125 to blacken the x-ray film. The pure emission from C-14 is completely absorbed by a thin aluminum sheet--hence no problem there. After the decay of Tc-99m, therefore, it was entirely feasible to continue autoradiography with I-125 (T1/2 = 60.2 days) or C-14 (T1/2 = 5730 yr). Based on these conditions, we applied (a) tracer microspheres labeled with I-125 and Tc-99m to define the respective perfusion areas of the left anterior descending, septal, and left circumflex coronary arteries of the beating heart, and (b) Tc-99m pyrophosphate and C-14 antipyrine to demarcate respectively the localization of the infarct-avid substance and the regional blood flow. We verified the first procedure with postmortem angiography and the second with histochemistry.

Angiography↗
PubMed1983

Decrease in the zinc turbidity test values in patients with liver cirrhosis: a possible indicator for impending hepatocellular carcinoma.

A retrospective investigation of 21 cases of hepatocellular carcinoma with liver cirrhosis presumably of viral origin revealed a significant fall in the value of the zinc turbidity test from 15.5 +/- 6.9 (mean +/- SD) at 1 year to 11.2 +/- 2.5 units at 6 months before the discovery of the carcinoma (p less than 0.05), and a return to 16.8 +/- 7.2 units one month after the diagnosis (p less than 0.05). The values at 6, 2 and 1 month before the diagnosis were significantly lower than that for 120 control cirrhotics without hepatocellular carcinoma at 16.3 +/- 7.2 units (p less than 0.05). The fall in value occurred before or concurrently with a rise in the alpha-fetoprotein level in three patients, in whom it has been determined serially. Based on the results obtained, the decrease in the zinc turbidity test value may be used as an indicator for impending hepatocellular carcinoma in patients with liver cirrhosis.

Adult↗
PubMedDate not supplied

Protective effect of 4-(3,7,11,15-tetramethyl-6,10,14-hexadecatrienoyl)morpholine on liver injury induced by hepatotoxins in rats.

The effect of 4-(3,7,11,15-tetramethyl-6,10,14-hexadecatrienoyl)morpholine (E-0712), a new synthetic compound, on liver injury induced by two hepatotoxins in rats was studied. Oral doses of E-0712 four times at 0, 6, 12 and 18 hr significantly attenuated elevated SGPT values and prolonged prothrombin time (PT) at 24, 36, 48, 60 and 72 hr in rats with a single s.c. dose of D-galactosamine in which SGPT values and PT reached the peak within 48 hr. In cases in which a dose of carbon tetrachloride (i.p.) produced peak SGPT values and PT within 36 hr attenuation occurred likewise at 24, 36 and 60 hr. In the control and E-0712-treated rats dosed with D-galactosamine or carbon tetrachloride, SGPT values were positively correlated with PT at 24 hr. In addition, morphological degrees of acidophilic body formation or centrizonal necrosis were significantly reduced by E-0712. These results suggest that E-0712 protects against liver injury, particularly hepatocellular necrosis, induced by D-galactosamine and carbon tetrachloride in rats.

Alanine Transaminase↗