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Biomedical subjects

H Nagashima

Publications and source records attributed to H Nagashima.

At least 343 records · Page 19Linked to original sources

A simple and rapid method for determining blood ammonia levels.

Blood ammonia levels in patients with various liver diseases were determined quantitatively by a simple and rapid method using the Amitest Meter System. The results were compared to those obtained by an enzymatic method and were well correlated. This simple Amitest is also useful in animal experiments, particularly when there is a need to determine blood ammonia levels serially. This paper test was evaluated as being accurate and reliable for clinical and experimental use.

Ammonia↗

Changes in stenosis resistance and myocardial blood flow after a brief coronary occlusion in the dog.

Stress-induced changes in the resistance due to coronary arterial stenosis of a fixed diameter and in the myocardial blood flow distal to the stenosis were investigated in the open-chest dog. Myocardial blood flow in the inner and outer third of the left ventricular wall was continuously measured with heated cross-thermocouples. The circumflex coronary artery was constricted with a thick string so that myocardial reactive hyperemia was nearly eliminated. Without constriction, a 15-second occlusion of the artery produced no significant changes in the resistance of large coronary arteries. On the contrary, in the presence of coronary constriction, a brief coronary occlusion caused a sustained decrease in distal coronary pressure and subendocardial myocardial flow during reactive hyperemia, while coronary flow returned quickly to the pre-occlusion level with significant reactive hyperemia of subepicardial flow. This change resulted in a long-lasting increase in the stenosis resistance. These results suggest that stenosis resistance changes dynamically, resulting in additional myocardial ischemia especially in the subendocardial myocardial layers.

Animals↗

Comparative study of amino acid, ammonia and pancreatic hormone levels in the blood of cirrhotic patients following intragastric and intravenous administration of a branched-chain amino acid-enriched solution.

The blood levels of amino acids, ammonia and pancreatic hormones following the intragastric and intravenous administration of a branched-chain amino acid (BCAA)-enriched solution were comparatively investigated in control subjects and patients with liver cirrhosis. There was no essential difference in the time course of serum amino acid and blood ammonia levels between the intragastric and intravenous infusions. Elevation of serum insulin concentrations in cirrhotic patients was significant only immediately after the administration through the enteral route. However, plasma glucagon levels increased similarly when the BCAA-enriched solution was administered through either route. The results indicate that both enteral and intravenous infusions will have similar therapeutic effects on the impaired protein metabolism in cirrhotic patients with protein-calorie malnutrition.

Amino Acids↗

Increase in the resistance of stenotic coronary segment by intravenous infusion of isoproterenol.

The effects of intravenous infusion of isoproterenol on stenosis resistance were studied in the anesthetized open-chest dog. The circumflex coronary artery (LCx) was isolated near its origin and an electromagnetic flow transducer was placed around the vessel for measuring coronary flow. A polyethylene catheter was inserted into the small branch of LCx for monitoring distal coronary pressure. LCx was constricted with a thick cotton string to a degree of obstruction that eliminated reactive hyperemia following a 20-second coronary occlusion. The coronary resistance across the stenotic segment (RL) was calculated as the pressure gradient across the stenosis divided by coronary flow. Isoproterenol was infused intravenously in a dose to keep the heart rate at a level 25-30% above the control with and without coronary constriction. For maintaining the ascending aortic pressure at the pre-isoproterenol level, the descending thoracic aorta was constricted with a tape. In the absence of coronary constriction, the vascular resistance of large coronary arteries was not affected by isoproterenol with a significant increase in coronary flow. In the presence of coronary stenosis, isoproterenol markedly increased RI regardless of additional aortic constriction. The magnitude of the increase in RL during aortic constriction varied directly with the percent increase in the pressure gradient across the coronary stenosis. Pacing-tachycardia essentially did not affect RL. These results suggest that isoproterenol increased the vascular resistance of the stenotic segment with fixed caliber.

Animals↗

Long-term survival in a case of hepatocellular carcinoma.

A patient with an unresectable hepatocellular carcinoma (HCC) who survived without active treatment 3 years and 8 months after histological diagnosis is described. The size of the liver, which was already quite huge at the time of diagnosis, changed little during the entire clinical observation. However, 2 months before death, his condition deteriorated rapidly following gastrointestinal bleeding due to the direct invasion of the stomach by HCC. A critical reason for the unusually long-term survival of the patient may stem from the facts that a well-differentiated and bile-producing HCC was extent in most encapsulated-tumor tissues and that liver cirrhosis was not present.

Carcinoma, Hepatocellular↗

Absence of Kupffer cells in carcinogen induced liver hyperplastic nodules: demonstration by intravenous injection of indian ink.

Absence of Kupffer cells in rat liver hyperplastic nodules induced by a chemical carcinogen was demonstrated by intravenous injection of indian ink. Hyperplastic nodules appeared 4 weeks after diethylnitrosamine (DEN) was administered, and the nodules continued growing and became eosinophilic hyperplastic nodules after 5 to 6 weeks. After intravenous injection of indian ink, hyperplastic nodules were observed as carbon-free white nodules, which were macroscopically distinguishable from the black surrounding tissue. As observed by light microscopy, Kupffer cells were absent in hyperplastic nodules in contrast to being present in the surrounding tissue. Scanning electron microscopy confirmed these findings and furthermore revealed that the sinusoidal endothelium of hyperplastic nodules had no fenestrae. Injection of indian ink is a useful method for delineation and enucleation of hyperplastic nodules in the study of morphological and chemical changes of nodules.

Animals↗

Peritoneoscopy of the liver after abdominal surgery.

The incidence of intraperitoneal adhesion after abdominal surgery was studied. Peritoneoscopy was performed in 933 patients with liver diseases over the 6 year 5 month period from March 1974 to July 1980. Of the patients, 352 (37.7%) had undergone an abdominal operation, and intraperitoneal adhesion was detected in 205 (58.2%) of these patients. The liver was not observable in 5 out of 61 patients with adhesions after upper abdominal operations. Whereas, the liver was clearly observable in patients with lower abdominal operations in spite of adhesions. Out of the 581 patients without any abdominal operations, 30 patients (5.2%) had adhesions in the abdominal cavity, and 6 of them had extensive adhesions that partially obscured the observation of liver surface. In all patients, peritoneoscopy was performed without complications by avoiding the surgical scar for puncture sites and ensuring a free air lumen before trocar puncture.

Abdomen↗

An adult case with rhabdomyosarcoma of the liver.

An autopsy case of primary rhabdomyosarcoma of the liver in a 70-year-old man is described. The case could not be clinically differentiated from hepatocellular carcinoma. The tumor showed typical features of rhabdomyosarcoma; phosphotungstic acid hematoxylin (PTAH)-positive myofibrils and cross-striations were observed in the cytoplasm of highly plemorphic tumor cells.

Aged↗

Muscular relaxation with atracurium, vecuronium and duador under balanced anaesthesia.

The neuromuscular effects of three new nondepolarizing neuromuscular blocking drugs, atracurium, vecuronium and Duador, were investigated in surgical patients under balanced anaesthesia. (The numbers of patients in each study are given in the tables.) There were no significant differences in the neuromuscular effects of the three agents. None showed any cumulation after repeated administration of maintenance doses. Muscular relaxation for upper abdominal surgery was adequate as long as the isometric twitch tension (P) was no more than 25% of control. Conditions for tracheal intubation were satisfactory within less than 3 min after the start of injection. Spontaneous recovery of P to 90-95% of control, after the last dose of neuromuscular blocker was the fastest with vecuronium (35.8 +/- 2.4 min) and about the same with atracurium (54.3 +/- 2.4 min) and Duador (54.2 +/- 4.7 min). The T4/T1 ratio at the time of greater than 90% recovery of P was 0.44, 0.52 and 0.56 with vecuronium, Duador and atracurium, respectively, indicating the need for the reversal of the residual neuromuscular block. This could be accomplished within 2 min by the i.v. injection of edrophonium 0.5 mg kg-1, preceded by atropine 0.01 mg kg-1. No side-effects were observed with vecuronium. Atracurium caused mild to moderate histamine release in four of 50 patients included in this study, all of whom received an initial dose of 0.5 mg kg-1. The initial dose of Duador caused a 16.7% increase in heart rate. The findings indicate that the three new muscle relaxants merit further clinical trial. In our opinion, until the results of such studies become available, atracurium should not be used in patients with a history of allergic diathesis and Duador in those in whom increased heart rate may be harmful.

Androstanes↗

Full and empty particles of hepatitis B virus in hepatocytes from patients with HBsAg-positive chronic active hepatitis.

Complete and defective hepatitis B virus (HBV) particles in sera and hepatocytes were observed by electron microscopy for an understanding of the maturation process of hepatitis B virus. To distinguish Dane particles with or without DNA on the basis of staining density with uranyl acetate, Dane particles, purified from sera of asymptomatic carriers, and Dane particle cores, separated by ultracentrifugation in a metrizamide density gradient, were observed by electron microscopy. Complete cores at a low density (1.19 to 1.23 gm/cm3) were electron dense and incomplete cores at a high density (1.23 to 1.27 gm/cm3) were partially electron dense or empty. These findings demonstrated that the presence or absence of DNA is reflected by the electron density of the core. Our result, in which less than 10% serum Dane particles have full cores in ultrathin sections of the pellet, is in agreement with Gerin's finding that defective Dane particles are predominent in sera. Naked core particles and Dane particles in two biopsy specimens from patients with hepatitis B surface antigen, hepatitis B e antigen, and DNA polymerase-positive, chronic active hepatitis were classified into complete versus incomplete particles on the basis of electron density. Nine hundred and fourteen naked core particles were detected in nuclei and cytosol of 68 hepatocytes. One hundred and five core particles (11.5%) were electron dense and 809 core particles (88.5%) were partially electron dense or empty. Furthermore, 488 Dane particles were observed in the cisternae of the endoplasmic reticulum of these hepatocytes. Fifty Dane particles (10.2%) had full cores, and 438 Dane particles (89.8%) had partially full or empty cores. These findings suggest that DNA may be incorporated into about 1 to 10% of core particles when they are assembled in nuclei of hepatocytes. Morphologic differences in damage to hepatocytes containing various frequencies of full Dane particles were also studied, but no significant correlation was found between damage in hepatocytes and frequency of full Dane particles.

Hepatitis B Surface Antigens↗

Increased 125I-labelled concanavalin A binding to erythrocytes in diabetes mellitus.

Percentage binding of 125 I-labelled concanavalin A to erythrocytes in diabetic patients was significantly higher than that in normal subjects (12.2 +/- 2.8 versus 8.1 +/- 1.8%, mean +/- SD, p less than 0.001). Insulin-dependent diabetic patients showed significantly higher concanavalin A binding than non-insulin-dependent diabetic subjects (15.0 +/- 1.4 versus 11.4 +/- 2.5%, p less than 0.01). There was a highly significant correlation between percentage binding of 125I-labelled concanavalin A and glycosylated haemoglobin.

Adult↗

Differential diagnosis of liver parenchymal diseases by likelihood method using 12 laboratory data and age.

Liver parenchymal diseases were statistically diagnosed by likelihood method using 12 routine liver function tests and age. 444 cases of liver diseases were classified into 8 groups by histological diagnosis. A score diagnosis table was made from the data of these cases. For the likelihood diagnosis, data of each case were adapted to the score table and the probable diagnosis was calculated. Correct diagnosis rate of the first probable diagnosis was 50% in all cases and that of the first and the second was 71%. Descending order of the correct diagnosis rate of the first diagnosis was fatty liver (76%), liver cirrhosis (67%), slight histological changes (61%), acute hepatitis (51%), alcoholic liver injury (48%), chronic aggressive hepatitis 2A (43%), chronic persistent hepatitis (40%) and chronic aggressive hepatitis 2B (26%). In conclusion, differential diagnosis of liver parenchymal diseases was made easily with the score table of 13 informations with a considerable success.

Adult↗

Peritoneoscopic study on rat liver cell necrosis induced by carbon tetrachloride and allyl formate.

The surface changes of acute centrolobular and perilobular necrosis were studied in rat liver using peritoneoscopy. Centrolobular necrosis as induced by carbon tetrachloride and perilobular necrosis by allyl formate. Vessels observed on the control rat liver surface were identified as terminal hepatic veins by irrigation of the hepatic vein with a barium solution. Polygonal whitish markings were observed on the liver surface 48 hours after carbon tetrachloride administration. Terminal hepatic veins were regularly distributed throughout the central portions of the whitish areas. Reddish spots about 0.1 mm in diameter were scattered about the terminal hepatic veins. The reddish spots and whitish areas corresponded to the histological findings of central liver cell necrosis and infiltration by Kupffer and white blood cells. Six hours after allyl formate administration, round reddish spots about 0.3 mm in diameter were regularly distributed on the liver surface among the terminal hepatic veins. These spots corresponded to the histological findings of liver cell necrosis around the portal area. In summary, acute centrolobular and perilobular liver cell necrosis were newly observed as reddish spots by peritoneoscopy.

Animals↗

Insulin and glucagon concentrations in the portal and peripheral blood in liver-injured and partially hepatectomized rats.

Insulin and glucagon concentrations in the peripheral and portal circulation were comparatively determined during 48 hours following partial hepatectomy and hepatotoxin treatment. Insulin and glucagon levels both in the peripheral and portal blood increased 24 hours after carbon tetrachloride (CCl4) and D-galactosamine administrations, when nearly maximum degree of liver injury has been occurred. Thereafter glucagon continued to rise further, but insulin diminished sharply at the 48th hour of the hepatotoxin treatment. In partially hepatectomized rats, glucagon levels both in the peripheral and portal blood increased to a greater extent but insulin only in the portal circulation slightly elevated. The liver under repaired process of acute CCl4 and galactosamine liver injuries can not uptake glucagon from the portal blood, but the regenerating liver following partial hepatectomy showed the increased uptake of glucagon as well as insulin. Different behaviors of glucagon uptake by the liver under these experimental conditions may support our previous observations that repair process of liver injury is pathophysiologically different from liver regeneration following partial hepatectomy.

Animals↗