Biomedical subjects

A Nonaka

Publications and source records attributed to A Nonaka.

At least 55 records · Page 3Linked to original sources

PubMed1992

Cardiac and hepatic metabolism in spontaneously hypertensive rats following acute blood loss.

Seven spontaneously hypertensive rats (SHRs) and eight Wistar-St rats were used to assess the influence of hemorrhage on myocardial and hepatic energy metabolism. They received 2% halothane and pancuronium, 0.3 mg.kg(-1), during preparation. After discontinuation of halothane, blood (2 ml.100 g body weight(-1)) was gradually withdrawn over a 5 min period from a femoral artery. Thirty min after induction of hemorrhage, the heart and liver were removed and myocardial and hepatic metabolites (ATP, lactate, pyruvate and glycogen) were measured by the enzymatic methods. Acidosis and decreased hematocrit were noted in the both groups after hemorrhage. Mean arterial pressure (MAP) in SHR was significantly higher than that in Wistar rat before hemorrhage. However, there were no significant differences in MAP and heart rate between the two groups after hemorrhage. Although there were no significant differences in cardiac metabolites, a significant decrease of hepatic ATP and an increase of hepatic lactate/pyruvate ratio were found in SHR when compared with Wistar rat. These results suggest that human hypertensive disease may run a high risk in connection with acute hemorrhage.

Journal Article↗

PubMed1992

Anesthetic influences on myocardial and hepatic energy metabolism in hemorrhaged spontaneous hypertensive rats.

Twenty four spontaneously hypertensive rats (SHRs) were used to assess the influence of anesthetics on myocardial and hepatic energy metabolism after hemorrhage. They were divided into four groups: a control group and three others which received pentobarbital (60 mg.kg-1 ip), 2.2% enflurane, or 1.4% isoflurane. Following a 10-min stabilisation period, blood (2 ml.100 g body weight-1) was gradually withdrawn over a 5-min period from a femoral artery. Thirty minutes after the induction of hemorrhage, the heart and liver were removed, and myocardial and hepatic metabolites (ATP, lactate, pyruvate, and glycogen) were measured by the enzymatic methods. Metabolic acidosis and decreased hematocrit were noted in all groups after hemorrhage. The mean arterial pressure in rats receiving anesthetics decreased significantly in comparison with the control group. There were significant increases of myocardial and hepatic lactate/pyruvate ratios in rats receiving enflurane when compared with controls. These results suggest that enflurane may be more detrimental than other anesthetics to the maintenance of anesthesia in hypovolemic SHRs.

Acidosis↗

PubMed1992

Effect of synthetic protease inhibitors on superoxide (O2-), hydrogen peroxide (H2O2) and hydroxyl radical production by human polymorphonuclear leukocytes.

The effects of clinically used protease inhibitors (aprotinin, nafamostat mesilate, gabexate mesilate) on the production of oxygen-derived free radicals (O2-, H2O2, .OH) by human polymorphonuclear leukocytes were examined. Nafamostat mesilate and gabexate mesilate markedly and dose-dependently inhibited zymosan-stimulated O2- production by human polymorphonuclear leukocytes. However, aprotinin had a slight scavenging effect on O2- produced by the xanthine-xanthine oxidase system. All the protease inhibitors inhibited H2O2 production, but had no significant scavenging effect on H2O2. Nafamostat mesilate and gabexate mesilate slightly inhibited .OH production. These results indicate that the synthetic protease inhibitors nafamostat mesilate and gabexate mesilate inhibit the production of various activated oxygen radicals by human polymorphonuclear leukocytes, and the differences in their inhibitory effects suggest that each synthetic protease inhibitor is specific for a particular oxygen-derived free radical.

Adult↗

PubMed1992

[Clinical manifestations and serum fentanyl concentrations during epidural high dose fentanyl anesthesia].

Twelve elective abdominal surgeries were performed under epidural anesthesia with high dose fentanyl. An epidural catheter was inserted at Th9-Th12 interspace and fentanyl 10 micrograms.kg-1 with [E (+)] or without [E(-)] epinephrine 1:100,000 was given for each group of 6 patients. After the administration of epidural fentanyl, arterial blood was sampled at 5, 10, 15, 30, 60, 120, 180, 240 minutes. The serum concentrations of fentanyl were measured by gas chromatography. The peak concentration of serum fentanyl was observed in the E (-) group, while that was not seen in the E (+) group. The time of reach maximum serum concentration after epidural fentanyl administration in the E (-) group was from 10 to 15 minutes. In two cases of E (-) group, the plasma concentration-time course could be fitted to two-compartment model. The others could be fitted neither to a two-compartment nor to a three-compartment model. In both groups, we could maintain anesthesia with enflurane of less than 0. 4%, and N2O, 66%. It is suggested that analgesic effect of fentanyl on opioid receptor of spinal cord plays a major role in this anesthesia method.

Abdomen↗

PubMed1991

Effect of a new synthetic ascorbic acid derivative as a free radical scavenger on the development of acute pancreatitis in mice.

The therapeutic effects of CV 3611, a new synthetic free radical scavenger prepared from an ascorbic acid derivative, on choline deficient, ethionine enriched (CDE) diet induced acute pancreatitis in mice were evaluated and compared with those of superoxide dismutase. Time/course studies after subcutaneous injection of CV 3611 in normal mice showed a peak plasma concentration of mean (SEM) 0.54 (0.09) micrograms/ml at one hour, with a gradual decrease over the next 10 hours, while a peak concentration in pancreatic tissue of mean (SEM) 425 (33) ng/g tissue was achieved at three hours and the drug was undetectable at 12 hours. Survival rates and activities of pancreatic enzymes (amylase, lipase, elastase I) were compared in control mice and animals that received CV 3611 before or at the time of feeding the CDE diet. The survival rate was observed in a no treatment group and mice given pretreatment or treatment with CV 3611 or superoxide dismutase. The survival rate was significantly better in the treatment group given CV 3611 (p less than 0.02), but superoxide dismutase had no significant effect on survival. The increases in the three serum enzyme activities were significantly less at 48 hours in the groups given pretreatment or treatment with CV 3611 than in the no treatment group. These results indicate that CV 3611, which has been proved to pass through the cell membrane and to have a long half life in plasma and tissue, had an important therapeutic effect on the development of acute pancreatitis. They also suggest that oxygen derived free radicals may play an important role in the development of acute pancreatitis.

Amylases↗

PubMed1991

[Epidural anesthesia with high dose fentanyl for thoracic surgeries].

Twenty-two elective thoracic surgeries were performed under epidural high dose fentanyl anesthesia. These included 11 mastectomies, 3 lung lobectomies, and 8 operations for esophageal carcinoma. Through an epidural catheter, 10 micrograms.kg-1 fentanyl with [E (+)] or without [E (-)] epinephrine (1: 100,000) was given. N2O (66%) and enflurane (0.2-0.8%) were also administered, and muscle relaxants were given as needed. The onset and duration of the action were approximately 20 minutes and 3 hours, respectively. Anesthesia was maintained with enflurane (up to 0.4%) in 17 patients (77.3%). There were no differences between the E (+) group and the E (-) group. Systolic pressure, diastolic pressure and heart rate during operations were about 30% lower than those observed before the operations. Patients recovered from anesthesia rapidly. Naloxone was administered intravenously in 6 patients after mastectomies or lung lobectomies (42.9%), whose respiratory rate was below 10.min-1. The patients with short operating time (shorter than 2 hours) needed more naloxone. Troubles did not occur either in the recovery room or in the ward with both naloxone and non-naloxone groups.

Adult↗

PubMed1990

The effects of ulinastatin on cardiac and hepatic energy metabolism in rats subjected to hypovolemic shock.

Ulinastatin is a trypsin inhibitor extracted from human urine. In this study the effects of ulinastatin on myocardial and hepatic tissue concentrations of creatine phosphate (CP), ATP, ADP, AMP, lactate, pyruvate, and glycogen have been investigated in rats which were in hemorrhagic shock state. Hypovolemia was induced by bleeding from the femoral artery, and systolic blood pressure was maintained 40 mmHg for 25 min, then ulinastatin 50,000 units.kg(-1) in saline or saline vehicle was intravenously administered. Thereafter the heart and liver were extirpated and frozen quickly with liquid nitrogen. The tissue concentrations of CP, ATP, ADP, AMP, lactate and glycogen were measured enzymatically. Systolic blood pressure elevated significantly after ulinastatin administration. The myocardial tissue CP level was higher in ulinastatin-treated group than that of control group, whereas no significant difference in energy charge between two groups. The hepatic tissue level of AMP, lactate and L/P ratio was lower in ulinastatin-treated group than that of control group, however, no significant difference was found in hepatic tissue level of ATP, ADP and energy charge. From these results it is concluded that ulinastatin can improve the energy metabolism of myocardium to some extent, but not of the liver in rats with hypovolemic shock.

Journal Article↗

PubMed1990

Effect of a new synthetic free radical scavenger, 2-octadecyl ascorbic acid, on the mortality in mouse endotoxemia.

Oxygen-derived free radicals have been implicated as mediators of cellular injury in several model systems. In order to clarify the role of oxygen radicals in endotoxemia, we measured the serial lipid peroxide changes resulting from systemic radical reactions using a newly developed colormetric method. To determine the effect of a free radical scavenger on mortality in endotoxemia, a new synthetic scavenger, 2-Octadecylascorbic acid (CV-3611), which overcome the detrimental properties (circulation half-life and cell penetration) of native SOD, was used in the model of mouse endotoxemia induced by the i.p. administration of E-coli endotoxin (10 mg/kg). Serial LPO (Lipid Peroxide) changes revealed significant elevations from the basal level of 4.52 +/- 0.79 nmol/ml to 10.5 +/- 2.04 nmol/ml at 2h (P less than 0.05), 12.0 +/- 2.44 nmol/ml at 8h (P less than 0.05), 32.8 +/- 12.5 nmol/ml at 12h (P less than 0.05) and 13.6 +/- 2.40 nmol/ml at 24h (P less than 0.05) following i.p. administration of E-coli. The circulation half life of CV-3611 was checked by a reversed-phase HPLC after 10 mg/kg s.c. administration. The level of CV-3611 reached peak levels of 0.54 +/- 0.10 micrograms/ml at 1h and 0.52 +/- 0.20 micrograms/ml at 2h then gradually decreased to the level of 0.04 +/- 0.004 micrograms/ml at 6h and to a non-detectable level at 24h after s.c. administration. Increased survival was seen at 2 days (P less than 0.001) after E-coli endotoxin administration in the CV-3611 treated group compared to the control group. These results suggest that oxygen derived free radicals contribute to mortality in mouse endotoxemia and that antioxidants such as CV-3611 may provide a new therapeutic avenue by improving survival of patients with gram-negative bacterial sepsis.

Animals↗

PubMed1990

Anesthetic influence on myocardial energy metabolism during hemorrhagic shock in rats.

Twenty-eight male Wistar rats were used to assess the influence of inhalation anesthetics on myocardial energy metabolism during hemorrhage. They were anesthetized with pentobarbital and divided into four groups: a control group and three others which received 1.2% halothane, 2.2% enflurane or 1.4% isoflurane, respectively. Following a 15-min stabilization period, blood was gradually withdrawn over a 5-min period from a femoral artery. Systolic blood pressure was maintained at 40 mmHg for 30 min. Immediately after hemorrhage, the heart was removed and myocardial metabolites (ATP, ADP, AMP, lactate and glycogen) were measured by the enzymatic methods. Although no significant differences could be detected in ADP, AMP and lactate among the groups, there were significant increases of ATP content in rats receiving halothane and isoflurane when compared with the controls. There were also differences in myocardial glycogen content between the control group and those receiving isoflurane with those receiving halothane or enflurane. These results suggest that halothane or isoflurane may be more desirable than enflurane for maintenance of anesthesia during hypovolemia.

Adenosine Triphosphate↗

PubMed1990

Adenoid cystic carcinoma with intracranial extension: report of three cases.

Adenoid cystic carcinoma (cylindroma) usually arises from the salivary, lacrimal, or other exocrine glands, and is rarely encountered by neurosurgeons. The authors describe three cases involving intracranial extension. An intraorbital tumor in a 71-year-old man extended directly into the epidural space of the frontal base and destroyed the orbital roof. In a 53-year-old woman, the tumor arose from the area adjacent to the eustachian tube and invaded the Gasserian ganglion. In the third patient, a 58-year-old man, the tumor originated in the maxillary sinus and extended directly into the middle cranial fossa. In all these cases, the tumors were removed to the fullest extent possible. Although residual tumor was markedly reduced by radiation therapy, recurrence and metastases occurred within a few years. Thus, adenoid cystic carcinoma appears to be radiosensitive, but not curable by irradiation. In treating a recurrent tumor in one patient, we applied the so-called "two-route" chemotherapy (cisplatin and its antidote) in combination with radiation therapy. The tumor responded well to this therapy, although multiple pulmonary and bone metastases eventually led to the patient's death.

Aged↗

PubMed1990

Changes in lipid peroxide and oxygen radical scavengers in cerulein-induced acute pancreatitis. Imbalance between the offense and defense systems.

The role of free radicals in the development of cerulein-induced pancreatitis was evaluated by measuring the activity of the endogenous scavengers, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHpx), as indicators of the defense system, and the level of lipid peroxide (LPO) in the pancreas, as an indicator of the offense system. Acute pancreatitis was induced by 5 hourly intraperitoneal administrations of cerulein (50 micrograms/kg body weight), in 0.9% NaCl, to mice. The presence of acute pancreatitis was confirmed by changes in serum amylase levels and in typical microscopical features. Regarding the changes in the levels of endogenous scavengers, the SOD level was decreased significantly from a basal level of 52.6 +/- 3.94 to 43.1 +/- 2.79 mU/micrograms DNA at 6 h (p less than 0.01) to 38.8 +/- 5.18 mU/micrograms DNA at 9 h (p less than 0.05) and to 31.7 +/- 3.10 mU/micrograms DNA at 12 h (p less than 0.01) after the first intraperitoneal cerulein injection. The CAT level also decreased significantly from a basal level of 7.80 +/- 0.27 to 5.86 +/- 0.46 mU/micrograms DNA at 9 h (p less than 0.01) and to 4.52 +/- 0.21 mU/microgram DNA at 12 h (p less than 0.01). GSHpx increased from a basal level of 6.80 +/- 0.43 to 7.58 +/- 0.50 mU/micrograms DNA at 9 h and to 10.2 +/- 0.52 mU/micrograms DNA at 12 h after the first intraperitoneal cerulein injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1990

Brain metastasis from transitional cell carcinoma of the bladder--case report.

A rare case of brain metastasis from a transitional cell carcinoma (TCC) of the bladder is presented. A 66-year-old female underwent total removal of a bladder carcinoma and postoperative radiation therapy and chemotherapy. Right hemiparesis and seizures developed about 16 months later, and a solitary brain metastasis was discovered in the left Rolandic area. The tumor was totally removed and microscopic examination showed it to be TCC.

Aged↗

PubMed1990

[Role of free radicals in the development of acute mild and severe pancreatitis in mice].

In order to clarify the role of free radicals in the pathogenesis of acute pancreatitis, we observed the effect of a new synthetic free radical scavenger (CV-3611) on the pathological state in the models of both caerulein and CDE-diet induced acute pancreatitis in mice. In both models of acute pancreatitis, the levels of serum amylase activity were reduced significantly by the treatment of CV-3611. Pancreatic edema formation was also reduced significantly at 3.5 and 9 h after the first caerulein i.p. injection. The 4 days survival rate in CDE-diet induced pancreatitis was significantly elevated from 41.2% to 81.3% by the treatment of CV-3611. These results indicate that this synthetic scavenger, which has a long circulation half life, high affinity to biomembrane and good cell penetration ability, is effective on the development of both severe and mild pancreatitis. The main pathogenesis of both models is suggested to be radical reactions on the biomembrane which is caused by the interreaction between endothelium and neurophile in caerulein induced pancreatitis, and by the lipid peroxidation on the biomembrane of the organella in the cell in CDE-diet induced pancreatitis.

Acute Disease↗

PubMed1990

Acute phenytoin intoxication associated with the antineoplastic agent UFT.

Antineoplastic drugs are known to affect the intestinal wall and suppress the absorption of phenytoin (PHT), resulting in a decrease in the serum PHT level. UFT (not an abbreviation) is a mixture of uracil, which enhances the activity of 5-fluorouracil (5-FU), and tegafur, a masked compound of 5-FU. The authors report three cases in which treatment of malignant brain tumors with UFT caused acute PHT intoxication. Two patients received PHT preoperatively at 150-200 and 270 mg/day, and showed serum PHT levels of less than 5 micrograms/ml. The third patient was started on 150 mg/day of PHT after surgery. Postoperatively, in addition to radiation therapy, each patient received 4 capsules of UFT (each containing 100 mg of tegafur) per day. Their serum PHT levels peaked at 48.2, 30.9, and 24.2 micrograms/ml, and all three exhibited clinical symptoms of acute PHT intoxication. The mechanism of interaction of these two drugs is obscure. Tegafur may compete with PHT in binding to metabolic enzymes in the liver and/or directly suppress PHT metabolism, leading to an increase in the serum PHT concentration. Therefore, when PHT is given in combination with a masked compound of 5-FU, the serum PHT level should be closely monitored.

Adult↗

PubMed1990

[Organ specific ESR features in mouse main organs and ESR application to the model of pancreatic disorders].

Nine main organs in the mouse were studied by ESR spectroscopy at 77K. Manganese ions were readily detected in the pancreas, small intestine, stomach and kidney. In particular, the pancreas gave strong ESR signals for the transition metal, suggesting that Mn(II) plays an important role in pancreatic function. All organs reveal different ESR spectra indicating organ specificity. C-centered radical, R-OO radical and C0Q10 or ascorbate radical are stable in the tissue. In the brain, heart and pancreas, N-centered radical heme-NO adduct was detected at 6 and 24 h after excision since common process is involved in tissue degeneration and ESR is sensitive to proteolysis and necrosis of tissues. In endotoxemia and/or CDE-diet-induced pancreatic lesions, R-OO radical and Mn(II) ion were detected in the signal at 77K. By the spin-trapping method (DMPO) at 25 degrees C, DMPO-OH adduct and 3-Line and 6-Line were detected in CDE diet-induced acute pancreatitis. These results suggest that damaged pancreatic tissues are in a highly oxidative environment that probably contains oxygen radicals, and that free radicals are considered to play an important role in the development of pancreatic lesions.

Animals↗

PubMed1990

[Repeated inadvertent subdural catheterization: a case report].

We had a patient who had repeated inadvertent subdural catheterization. Eighty-two year old woman with post herpetic neuralgia had a continuous epidural anesthesia for the relief of pain. An epidural catheter was inserted at the Th 5-6 interspace using a paramedian approach. Fifteen minutes after 4 ml test dose of 1% lidocaine injection, she developed circulatory depressions and massive sensory block. The exact position of the catheter and the distribution of the local anesthetic agent were confirmed by radiographic contrast material. The catheter was observed in the subdural space. Anesthesia was therefore continued with an injection of 1.5 ml mepivacaine. After one month, epidural catheterization was done in the same patient. The catheter was inserted in subdural space again. The subdural injection has been implicated in a case in whom there has been extensive spread of an epidural block. The diagnosis of subdural block can be made by a subsequent injection of contrast medium, since an unusual clinical course might be seen. Subdural space has a poor blood supply, and injected medium may stay in this space for considerable period of time. Subdural catheterization in epidural anesthesia probably occurs more frequently than previously recognized.

Aged↗

PubMed1989

Radical pancreatectomy for ductal cell carcinoma of the head of the pancreas.

Seventy-four patients were treated with a radical or a nonradical pancreatectomy for ductal cell carcinoma of the head of the pancreas. Their survival rates and the selection of the operative procedure were evaluated. In 32 patients, a radical pancreatectomy was attempted where there was sufficient clearance of regional or juxta-regional lymph nodes beyond the group of suspected metastatic nodes, as well as a resection of a greater margin of soft tissue around the pancreas. These patients' cumulative 5-year survival rate was 33.4%. In 14 Stage I or Stage II patients, the cumulative 5-year survival rate was 46.4%. In 18 Stage III or Stage IV patients, the cumulative 5-year survival rate was 20.7%. For 42 patients treated with a nonradical pancreatectomy with the dissection of lymph nodes adjacent to the pancreas or of regional lymph nodes but with insufficient clearance of the soft tissue around the pancreas, the cumulative 2-year and 3-year survival rates were 5.4% and 0%, respectively. In seven patients with Stage II carcinoma, the survival rate was 16.7% after 2 years and 0% after three years. In 35 Stage III or Stage IV patients, the survival rate was 3.2% after 2 years and 0% after 3 years. Thus, the survival rates were significantly higher in patients treated with radical operation than in patients who had nonradical operation. These results indicate that a radical pancreatectomy with sufficient lymph node clearance with the surrounding connective tissue around the pancreas is indispensable to cure patients with ductal cell carcinoma of the pancreas.

Adult↗

PubMed1989

Effects of sevoflurane with or without nitrous oxide on cardiac contractility and sinoatrial node rate.

Cardiac effects of sevoflurane (SE) with or without nitrous oxide were examined in the canine blood-perfused papillary muscle and sinoatrial node preparations. Although SE depressed developed tension (DT), mean arterial pressure (MAP) and heart rate of the donor dog (DHR) dose dependently, sinoatrial rate (SAR) was not changed significantly. No significant changes in MAP, DHR and SAR were observed with the addition of nitrous oxide to SE. However, the addition of nitrous oxide to SE resulted in significant decrease of DT. These results suggest that SE depresses BP and cardiac contractility dose dependently, but dose not change heart rate. The combination of nitrous oxide and SE may produce less cardiovascular depressant effect at a given MAC level than SE given alone.

Journal Article↗