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Biomedical subjects

A Iguchi

Publications and source records attributed to A Iguchi.

At least 217 records · Page 12Linked to original sources

Intravesical therapy with adriamycin plus verapamil in patients with superficial bladder cancer: a pilot study.

Nineteen patients with histologically proven superficial bladder cancer (Ta, T1) were treated with intravesical instillation of 30 mg of adriamycin (ADM) dissolved in 24 ml physiological saline plus 15 mg of verapamil (VR) (6 ml) every day for 10 days. In spite of the short period of treatment, 6 of the 18 evaluable patients (33.3%) showed complete response (CR) and a further 5 (27.8%) showed partial response (PR). Five of the 6 patients with CR were recurrent cases who had previously received prophylactic intravesical instillation chemotherapy including ADM. Irritative urinary symptoms were observed in 11 of the 19 patients (57.9%). However, these symptoms were mild in the majority of patients and the treatment was completed without interruption in all but 1 patient. There was no significant absorption of ADM and VR into the systemic circulation. No clinical evidence of systemic toxicity was observed. These results suggest that combination of ADM and VR has a possibility to be a useful prophylactic intravesical instillation chemotherapy after endoscopic resection of not only primary but also recurrent chemoresistant bladder cancers.

Administration, Intravesical↗

Effect of intrahypothalamic injection of neostigmine on the secretion of epinephrine and norepinephrine and on plasma glucose level.

We previously reported that the injection of neostigmine, an inhibitor of acetylcholinesterase, into the third cerebral ventricle of fasted rats produced hyperglycemia associated with the secretion of epinephrine and norepinephrine. However, the central nervous system site of action of neostigmine by which the plasma catecholamine and glucose concentrations were increased is not known. In this study we injected neostigmine into the ventromedial hypothalamus, lateral hypothalamus, paraventricular hypothalamus, median site of the lateral-preoptic area, lateral site of the lateral-preoptic area, anterior site of the anterior hypothalamic area, mammillary body (posterior mamillary nucleus), and cortex of anesthetized fasted rats and measured the plasma levels of glucose, epinephrine, and norepinephrine. It was found that the ventromedial hypothalamus, lateral hypothalamus, paraventricular hypothalamus, and median site of the lateral-preoptic area were involved in increasing the plasma levels of glucose and epinephrine. From this evidence we conclude that neostigmine acts on selected regions known to be involved in glucoregulation in the hypothalamus to increase the plasma levels of epinephrine and glucose.

Animals↗

Effects of the protein phosphatase inhibitors okadaic acid and calyculin A on insulin release from rat pancreatic islets.

The role of protein phosphatases in the regulation of insulin release from rat pancreatic islets was studied with protein phosphatase inhibitors, okadaic acid and calyculin A. Okadaic acid inhibited glucose- and glyceraldehyde-induced insulin release dose-dependently and also inhibited the potentiation of glucose-induced release either by adding forskolin, an activator of adenylate cyclase or by increasing K+ concentration to 25 mM. At a non-stimulatory concentration of 3 mM glucose, a high concentration (2 microM) of okadaic acid inhibited insulin release induced by high K+ or 12-O-tetradecanoylphorbol-13-acetate (TPA), an activator of protein kinase C, but a low concentration (1 microM) of okadaic acid did not significantly inhibit TPA-induced insulin release. Calyculin A also inhibited glucose-induced insulin release, and the effect was greater than that of okadaic acid. The data suggest that protein phosphatases may play an important role in the regulation of insulin release.

Animals↗

["Dismembered spiral flap pyeloplasty" for uretero-pelvic junction obstruction].

We report a new operative technique for plastic correction of uretero-pelvic junction (UPJ) obstruction: dismembered spiral flap pyeloplasty. It is similar to the method described by Culp & DeWeerd in that a flap is made spirally but different in that UPJ is detached. Relatively a long and wide spiral (oblique) flap, the apex of which directs cranioventrally or craniodorsally, is made using the dilated pelvis. The apex of the flap is reflected downward and anastomosed to the split ureteral end. Because the flap is made obliquely, one side of the flap base is approximated to the opposite pelvic margin; this helps to make gradual funnelling of pelvio-ureteric transition. The method seems to be fit for cases with considerably long stenosis of UPJ and with the UPJ locating relatively close to the medial margin of the renal parenchyma. Seven of 26 pyeloplasties were done by this method in our institute, and all the 7 cases had satisfactory results.

Adolescent↗

Changes in myocardial beta-adrenergic receptors during acute rejection of heterotopically transplanted rat hearts.

To evaluate changes of the myocardial beta-adrenergic receptors in acute cardiac graft rejection, the density and binding affinity value of the myocardial beta-adrenergic receptors in heterotopically transplanted rat isografts and allografts were analyzed. Hearts from Fisher rat donors were transplanted either to the Fisher rats (isografts) or to Lewis rats (allografts). Histologic examination of the allografts showed mild to moderate rejection on the seventh and fourteenth days and showed severe rejection on the twenty-first day after transplantation. The density values in the allografts and isografts similarly increased significantly (p < 0.05) above the normal level on the seventh and fourteenth days after transplantation. The density in allografts on the twenty-first day decreased significantly (p < 0.05) below the normal level, while that in isografts remained at the normal level. In contrast, the binding affinity value of myocardial beta-adrenergic receptors in both isografts and allografts did not change after transplantation. These results demonstrated that myocardial beta-adrenergic receptors presented upregulation in mild to moderate rejection, whereas these receptors presented downregulation in severe rejection. The data suggested that downregulation of myocardial beta-adrenergic receptors plays a major role in decreased cardiac contractility during severe rejection, but not during mild and moderate rejection.

Abdomen↗

[Separate perfusion of upper and lower body for ruptured thoracoabdominal aortic aneurysm--a case report].

A case of ruptured thoracoabdominal aortic aneurysm was presented. The patient had emergent replacement of thoracoabdominal aorta with an aid of separate perfusion of upper and lower body. The postoperative course was uneventful. It was suggested that separate perfusion of upper and lower body was useful in the patients who require extensive aortic replacement and who are at substantial risk for spinal cord injury.

Aorta, Abdominal↗

Reciprocal changes of plasma glucose and ketone bodies in fasted and acutely diabetic rats after CNS stimulation.

To assess the effect of chemical stimulation of the central nervous system (CNS) on ketogenesis, we injected neostigmine (5 x 10(-8)mol) into the third cerebral ventricle in normal rats fasted for 48 h and fed rats with diabetes induced by streptozotocin (STZ, 80 mg/kg). The hepatic venous plasma levels of ketone bodies (3-hydroxybutyrate and acetoacetate), free fatty acids (FFA), and glucose were measured for 120 min after the injection of neostigmine under pentobarbital anesthesia. In the normal rats, plasma glucose levels were significantly increased but neither ketone bodies nor FFA were affected by CNS stimulation with neostigmine. In contrast the plasma levels of ketone bodies and FFA were significantly increased in STZ-diabetic rats, while glucose levels remained unchanged. The intravenous infusion of somatostatin (1.0 microgram/kg/min) suppressed the increase in plasma ketone bodies following CNS stimulation in STZ-diabetic rats. These findings suggest that CNS stimulation with neostigmine may accelerate ketogenesis by promoting the lipolysis, which may be induced by glucagon, in fed diabetic rats but not in normal fasted rats.

Animals↗

Hyperglycemia induced by hippocampal administration of neostigmine is suppressed by intrahypothalamic atropine.

We investigated the relationship between the hyperglycemia induced by the administration of neostigmine into the hippocampus and the hypothalamus. Prior to the injection of neostigmine (5 x 10(-8) mol) into the hippocampus, 1 microliter each of atropine or hexamethonium (5 x 10(-11)-5 x 10(-8) mol) was injected into the bilateral ventromedial hypothalamus (VMH). Atropine suppressed in a dose-dependent manner the hyperglycemia induced by hippocampal administration of neostigmine, whereas hexamethonium had no significant effect. These observations suggest that the pathway for this experimental hyperglycemia involves, at least in part, the muscarinic cholinergic neurons in the VMH.

Animals↗

Relative contribution of nervous system and hormones to CNS-mediated hyperglycemia is determined by the neurochemical specificity in the brain.

To determine whether CNS regulatory pathways are organized so that differential sympathetic outflow patterns occur in response to stress, we injected various doses of neostigmine or bombesin into the third cerebral ventricle of fed rats, and then measured the hepatic venous plasma concentrations of glucose, glucagon, insulin, and epinephrine. The following four groups of rats were studied. Group 1 was intact rats. Group 2 comprised intact rats receiving the constant infusion of a) somatostatin to inhibit the endogenous secretion of insulin and glucagon, and b) insulin to maintain the plasma insulin concentration at basal levels. The infusion was started from -30 minutes and given via a catheter in the femoral vein. Group 3 consisted of rats that underwent bilateral adrenal medullectomy (ADMX) one week before the experiment. Group 4 was ADMX rats administered a constant infusion of somatostain with insulin through a femoral vein, as above. The administration of 1 x 10(-9) mol neostigmine caused hepatic venous hyperglycemia mediated by three distinct pathways: 1) direct innervation of the liver, 2) a direct action of epinephrine on the liver, and 3) the action of glucagon on the liver. We estimated the relative contribution of these three factors to be about 47, 32, and 21%, respectively. Relative contributions of three factors of the doses of 5 x 10(-9) and 5 x 10(-8) mol neostigmine demonstrated an effect similar to that of 1 x 10(-9) mol neostigmine. Epinephrine was shown to be the only agent involved in the hyperglycemic response to intraventricular bombesin at doses of 1 x 10(-10), 1 x 10(-9), and 1 x 10(-8) mol.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Medulla↗

Dissociation of hyperthermic and hyperglycemic effects of central prostaglandin F2 alpha.

We previously reported that intraventricular prostaglandins (PGs) produced hyperthermia and hyperglycemia in anesthetized rats. However, the relationship of them is little known. We examined the relationship between hyperthermia and hyperglycemia induced by intraventricular PGF2 alpha using curarized and adrenal demedullated rats. Iv curare completely prevented the PGF2 alpha-induced hyperthermia, but enhanced the hyperglycemic effect of PGF2 alpha. Adrenal demedullation completely prevented the hyperglycemia, but did not affect the hyperthermic effect of PGF2 alpha. To further assess the site of action concerned with PGF2 alpha-induced thermoregulation and glucoregulation in the central nervous system (CNS), we injected saline or PGF2 alpha into the preoptic area of the anterior hypothalamus (POA) in intact rats. After microinjection of PGF2 alpha into the POA, the rectal temperature rose, but the plasma glucose level did not increase significantly, as compared with saline-treated control rats. These results suggest that PGF2 alpha causes the central nervous system to produce hyperthermia via shivering, stimulated the somatic motor system, and to produce hyperglycemia by stimulating central sympathetic outflow to the adrenal medulla, but these operate independently under different neural regulation, and these sensitive sites are organically dissociated in the CNS.

Adrenal Medulla↗

CNS stimulation does not affect hepatic venous glucose concentration in severely diabetic rats.

To assess the role of the central nervous system (CNS) in carbohydrate metabolism in diabetes, neostigmine was injected into the third cerebral ventricle in fed rats with streptozotocin (STZ; 80 mg/kg)-induced diabetes under pentobarbital sodium anesthesia. Changes in hepatic venous plasma glucose concentrations were monitored. Neostigmine injection caused no significant changes in the hepatic venous plasma glucose concentration in untreated diabetic rats, whereas the glucose level increased significantly in insulin-treated diabetic rats similarly to the changes in normal control animals. In diabetic rats, the plasma levels of glucagon, epinephrine, and norepinephrine were increased significantly by neostigmine. After various doses (35-80 mg/kg) were given to rats, it was found that the higher the STZ dose, the lower was the hepatic glycogen content and the smaller was the glycemic response to neostigmine. Our results indicate that, in severe diabetes, CNS stimulation with neostigmine fails to increase hepatic glucose output, because glycogen stores are nearly exhausted and gluconeogenesis is already maximal.

Animals↗

Relative contribution of nervous system and hormones to hyperglycemia induced by thyrotropin-releasing hormone in fed rats.

In a continuation of our studies on the mechanism of central nervous system induced hyperglycemia in the rat, we evaluated the relative contribution of a direct neural effect on the liver and of certain hormones to the hyperglycemia induced by administration of thyrotropin-releasing hormone (TRH). The findings were compared with those of a previous investigation using neostigmine or 2-deoxy-D-glucose. In the present study TRH was injected into the third cerebral ventricle of rats, and the concentrations of hepatic venous plasma glucose, immunoreactive glucagon, immunoreactive insulin, epinephrine, and norepinephrine, were measured. Four groups of animals were evaluated: (1) intact rats; (2) rats receiving an infusion of somatostatin with insulin via the femoral vein to inhibit glucagon secretion and to maintain the basal insulin level; (3) rats bilaterally adrenalectomized (ADX) to prevent epinephrine secretion, and (4) ADX rats administered an infusion of somatostatin and insulin. Evaluation of the areas under the glucose curves for the rats receiving somatostatin with insulin, ADX rats, and ADX rats receiving somatostatin with insulin showed values 202, 50, and 79% of those observed in intact animals. These observations suggest that TRH-induced hyperglycemia results from at least two effects: a direct neural effect on the liver including a suppressive effect of epinephrine on insulin secretion (contributing about 79% to the total hyperglycemic effect) and a direct effect of epinephrine on the liver (contributing about 21% to the total hyperglycemic effect).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenalectomy↗

[Urinary cytology studied during 10 days after transurethral resection of bladder tumour and its relation to tumour recurrence].

Whether or not recurrence is related to the results of urinary cytology examined within 10 days after transurethral resection of bladder tumour was studied retrospectively in 47 patients with superficial bladder tumour. Of 7 cases with positive cytology during the postoperative 10 day period, 4 cases had a later recurrence of tumour and 2 cases had a residual tumour due to incomplete resection of original tumour. By microscopic chromocystoscopy, in 11 patients concurrent urothelial atypia (carcinoma in situ or dysplasia) was found in the apparently normal mucosa. Nine of the 11 cases had a later recurrence of tumour or a residual tumour. Of in total 15 patients combined with abnormal cytology and concurrent urothelial atypia, 12 (80%) were found with recurrence of tumor cystoscopically 4 approximately 64 months (mean; 20.6 months) after TUR. This recurrence rate was significantly (p less than 0.05) higher than that (42.4%) in patients without positive cytology and concurrent urothelial atypia. These results suggest that positive urinary cytology during 10 days subsequent to TUR and/or association with concurrent urothelial atypia are indicative of later tumour recurrence, incomplete resection of tumour or presence of additional occult tumour foci.

Humans↗

[Serious complication of retrograde perfusion during repair of dissecting aneurysm: compression of the true lumen].

Between 1982 and 1990, 61 patients underwent the repair of dissecting aneurysm. Retrograde perfusion from the unilateral femoral artery were performed for 56 patients and the selective false lumen perfusion occurred in 3 patients. As for those 3 patients, compression of the true lumen and insufficient cerebral perfusion were suspected. Selective cerebral perfusion and antegrade systemic perfusion from the ascending aortic graft were performed. Although 2 patients took uneventful postoperative courses, 1 patient died of massive brain damage. It is very important to accomplish the means to maintain adequate cerebral circulation as soon as possible toward this fetal complication.

Adult↗

[Is the new WHO's histological typing clinically useful for the diagnosis of follicular cancer of the thyroid?].

We tried to re-diagnose our 57 cases of thyroid follicular cancer between 1965 and 1988 in accordance with Histological Typing of Thyroid Tumours published by WHO in 1988. 1) The incidence of follicular cancer in differentiated cancers was decreased from 17.9% to 8.3% (26 cases). The number of widely invasive type and minimally invasive type was 13 cases equally. 2) Twenty four cases were diagnosed as papillary cancer. The reason was that 20 cases had a small focus of papillary structure, and other 4 cases had features of follicular variant type of papillary cancer. These 24 cases had good prognosis as our 262 cases of papillary cancer, in contrast to 26 cases of follicular cancer having worse prognosis. 3) The incidence of distant metastasis in follicular carcinoma was increased from 28.1% to 42.3%; 23.9% in minimally invasive type and 61.5% in widely invasive type, respectively. New WHO classification is acceptable according to this clinical study of our cases. We would have to treat more aggressively the patient diagnosed follicular cancer by WHO classification because of high incidence of distant metastasis.

Adenocarcinoma↗

[Analysis of hepatic and renal dysfunction after surgery of thoracic aneurysm].

To analyze causes of postoperative hepatic and renal dysfunction in patients with thoracic aneurysm, we examined 31 patients who survived surgeries and 2 patients died of MOF. The patients were separated into three groups as follows; Cardiopulmonary bypass (CPB) was used for circulatory support in group A (n = 7), CPB and low flow perfusion during open distal anastomosis in group B (n = 13) and temporary bypass or left atrial distal aorta arterial bypass was used in group C (n = 11). Operation time was significantly longer in group A (9.8 hrs) compared with group C (6.1 hrs). Amount of intraoperative blood transfusion was greater in groups A (4980 ml) and B (4860 ml) compared with group C (2320 ml). Postoperative highest total bilirubin level was significantly greater in group A (7.8 mg/dl) than group C (2.5 mg/dl). LDH was higher in groups A (1322 IU/l) and B (1336 IU/l) than group C (991 IU/l). GOT was higher in group B (200 IU/l) than group C (64 IU/l). There were no significant differences in GPT, creatinine and BUN among the three groups. Operation time and amount of intraoperative blood transfusion were positively correlated with postoperative hepatic function parameters. Two patients died of MOF showed severe hepato-renal dysfunction associated with LOS. The results indicate that hypothermic low flow perfusion during open distal anastomosis do not induce hepatic or renal dysfunction, and postoperative hyperbilirubinemia is resulted from bilirubin overload which patients can tolerate well if they are not complicated with MOF.

Aged↗

Neither adrenergic nor cholinergic antagonists in the central nervous system affect 2-deoxy-D-glucose(2-DG)-induced hyperglycemia.

To investigate whether the brain adrenergic and cholinergic neurotransmitter systems are involved in the regulation of 2-deoxy-D-glucose (2-DG)-induced hyperglycemia, we studied the effects of adrenergic and cholinergic antagonists on 2-DG-induced secretion of epinephrine and glucagon, and hyperglycemia, in anesthetized fed rats. When 2-DG (10 mg/10 microliters) was injected into the third cerebral ventricle, hepatic venous plasma glucose, glucagon, and epinephrine concentrations were significantly increased. Co-administration of phentolamine, propranolol, atropine and hexamethonium (1 X 10(-7) mol) with 2-DG did not modify the hyperglycemia and hormonal responses normally observed after the administration of 2-DG alone. From this evidence we concluded that neither brain adrenoceptive nor cholinoceptive neurons are involved in the regulation of 2-DG-induced hyperglycemia.

Adrenergic Fibers↗