Biomedical subjects

S Satoh

Publications and source records attributed to S Satoh.

At least 541 records · Page 30Linked to original sources

PubMed1992

Preliminary experience using laparoscopic transcystic cholangioscopy for treatment of common bile duct stones.

Laparoscopic transcystic cholangioscopy (LTC) in combination with electrohydraulic lithotripsy may be an alternative treatment to ERCP and sphincterotomy in patients with both gallbladder and common bile duct stones undergoing laparoscopic cholecystectomy. Preliminary experience using LTC lithotripsy in 13 cases is reported. In 12 cases the stones were pushed out into the duodenum using the tip of the cholangioscope, in 8 of them stone disintegration via LTC lithotripsy also being required. In the remaining case the cholangioscope could not be inserted into the common bile duct via the cystic duct due to complete cystic duct obstruction. The average hospital stay was 9 days (range 6-16) in patients with LTC/lithotripsy, which did not differ significantly from 8.4 days (range, 4-19) (n = 330) in the group undergoing laparoscopic cholecystectomy alone. The patients usually resumed normal activity the day after discharge. LTC lithotripsy has the advantages over endoscopic sphincterotomy of a shorter treatment and preservation of a normal functioning sphincter of Oddi. Further technical improvements, especially the development of a cholangioscope for this purpose, are urgently required.

Adult↗

PubMed1992

Clinical and basic aspects of an anorexiant, mazindol, as an antiobesity agent in Japan.

The Japanese Mazindol study group investigated the action of an anorexiant, mazindol, and found that it reduced food intake by directly suppressing neurons in the lateral hypothalamus, inhibited gastric acid secretion, increased motor activity, decreased glucose absorption, and inhibited insulin secretion. It thus appears that the main effect of mazindol is to decrease food intake through suppressing feeding centers in the hypothalamus. A multicenter open study of mazindol in Japan revealed that loss of body weight and relative body weight in 14 wk were 4.6 kg and 9.2%, respectively, with suppression of appetite in the majority of obese patients. A multicenter double-blind study demonstrated that mazindol was superior to the placebo in the treatment of simple obesity. We also suggest that mazindol is effective in the maintenance of reduced body weight after obesity therapy and in the treatment of obesity-related diseases such as diabetes, hypertension, or hyperlipidemia.

Animals↗

PubMed1992

Effects of dopamine receptor and alpha 2-adrenoceptor agonists and antagonists on muscarinic receptor stimulation in cardiac sympathetic ganglia of the dog.

The effects of dopamine (DA)-receptor and alpha 2-adrenoceptor agonists and antagonists on ganglionic muscarinic stimulation were examined in anesthetized dogs. All drugs were injected or infused intra-arterially into the blood supply of the cardiac sympathetic ganglia. The muscarinic agonists McN-A-343 (10, 20, and 30 micrograms) and muscarine (1, 2, and 3 micrograms) increased heart rate. The muscarinic receptor stimulation elicited by McN-A-343 or muscarine was significantly inhibited by infusion of the DA2-receptor agonist quinpirole (3 and 10 micrograms/min) but not by the DA1-receptor agonist SK&F 38393 (10 and 30 micrograms/min). The alpha 2-adrenoceptor agonist BHT 933 (3 and 10 micrograms/min) also inhibited muscarinic receptor stimulation. The DA2-receptor antagonist domperidone (10 micrograms/min) and the alpha 2-adrenoceptor antagonist yohimbine (1 micrograms/min) had no effects on muscarinic receptor stimulation, but they antagonized the inhibitory effects of quinpirole and BHT 933, respectively. The nicotinic transmission elicited by preganglionic cardiac sympathetic nerve stimulation (1 and 2 Hz) was also inhibited by DA-receptor and alpha 2-adrenoceptor agonists and antagonists. These results suggest that DA2-receptors and alpha 2-adrenoceptors suppress muscarinic transmission as well as nicotinic transmission in the cardiac sympathetic ganglia of the dog.

(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethy↗

PubMed1992

Facilitatory role of the renin-angiotensin system in controlling adrenal catecholamine release in hemorrhaged dogs.

Effects of the renin-angiotension system (RAS) on adrenal catecholamine release in response to hemorrhagic hypotension and splanchnic nerve stimulation (SNS) were studied in pentobarbital-anesthetized dogs. In hemorrhage experiments, mean blood pressure (MBP) was maintained at 50 mm Hg for 60 min by bleeding the arterial blood into a pressurized bottle. In the renal intact group (control), epinephrine (EPI) and norepinephrine (NE) output from the adrenal gland increased markedly during hemorrhagic hypotension: from 45 +/- 13 and 4.7 +/- 0.9 to 1,167 +/- 202 and 169 +/- 30 ng/min at 60 min after onset of hemorrhage, respectively. The increases in catecholamine output during hemorrhagic hypotension in the renal-intact group pretreated with captopril (1 mg/kg intravenously, i.v.) and in the renal-ligated group were significantly smaller than those in the control group. The increases in catecholamine output in the renal-ligated group infused with angiotensin II (AngII 10 ng/kg/min i.v.) were comparable to those in the control group. In SNS experiments, AngII infusion (10 ng/kg/min i.v.) enhanced increases in catecholamine output induced by 3 Hz SNS significantly. Captopril (1 mg/kg i.v.) did not affect the SNS-induced increases in catecholamine output. These results suggest that the renal RAS facilitates reflex release of adrenal catecholamines during hemorrhagic hypotension, at least in part, by acting directly on the release process of catecholamines from dog adrenal gland.

Adrenal Glands↗

PubMed1992

Effects of pirenzepine and hexamethonium on adrenal catecholamine release in responses to endogenous and exogenous acetylcholine in anesthetized dogs.

We investigated the way in which hexamethonium and pirenzepine, a selective muscarinic (M) 1 receptor antagonist, modify the release of catecholamines from dog adrenal gland in response to endogenous and exogenous acetylcholine (ACh) in vivo. Output of epinephrine (EPI), and norepinephrine (NE) was determined from adrenal venous blood by high-performance liquid chromatography (HPLC) with electrochemical detection. Intraarterial (i.a.) injections of ACh (1.5 and 3 micrograms) or muscarine (3 and 6 micrograms) into the phrenicoabdominal artery and splanchnic nerve stimulation (SNS, 3 Hz) produced marked increases in EPI and NE output. Hexamethonium (1 mg/kg intravenously, i.v.) inhibited the increases in EPI and NE output in response to exogenous ACh and SNS. Pirenzepine (10 micrograms/kg i.v.) inhibited the ACh-induced increases in EPI and NE output but did not modify the SNS-induced increases. The muscarine-induced increases in EPI and NE output were also inhibited by pirenzepine. These results indicate that the exogenous ACh-induced release of adrenal catecholamines is mediated through both nicotinic and M1 receptors, in contrast to the predominant mediation of nicotinic receptors in response to endogenous ACh.

Acetylcholine↗

PubMed1992

The treatment of osteoporotic-posttraumatic vertebral collapse using the Kaneda device and a bioactive ceramic vertebral prosthesis.

Twenty-two patients with neurologic deficit due to delayed posttraumatic vertebral collapse after osteoporotic compression fractures of the thoracolumbar spine underwent anterior decompression and reconstruction with bioactive Apatite-Wollastonite containing glass ceramic vertebral prosthesis and Kaneda instrumentation. Eighteen patients previously had minor trauma that resulted in a mild vertebral compression fracture without any neurologic involvement and were either conservatively treated or not treated at all. Four had no history of back injury. The preoperative neurologic status was incomplete paralysis in all patients. The average age at surgery was 66 (53-79) years. The average follow-up was 34 (20-58) months after surgery. All patients had returned to their daily living with neurologic recovery and stable spine. This type of anterior procedure is effective in the osteoporotic patients and there was a very low incidence of instrumentation failure and very low morbidity.

Aged↗

PubMed1992

Enhancement by endothelin-1 of the release of catecholamines from the canine adrenal gland in response to splanchnic nerve stimulation.

1. The effect of endothelin-1 on the release of adrenal catecholamines was examined in anaesthetized dogs. 2. Splanchnic nerve stimulation (SNS) at 1 and 3 Hz was applied before and after the intravenous injection of endothelin-1. 3. Endothelin-1 (0.1 and 0.3 micrograms/kg) significantly enhanced the release of adrenal catecholamines induced by 3 Hz SNS, but did not affect basal release and the release of adrenal catecholamines induced by 1 Hz SNS. 4. Endothelin-1 produced a slight and short-lasting fall in arterial blood pressure and decreases in adrenal and renal blood flow rates. 5. These results indicate that endothelin-1 enhances the release of adrenal catecholamines from the canine adrenal gland in response to relatively high frequency SNS.

Adrenal Glands↗

PubMed1992

Distribution of manganese superoxide dismutase in rat stomach: application of Triton X-100 and suppression of endogenous streptavidin binding activity.

The distribution of rat manganese superoxide dismutase (Mn-SOD) was immunohistochemically investigated in the rat stomach with a specific polyclonal antibody and a labeled streptavidin-biotin immunoglobulin detection system in cryosections. Parietal cells in the stomach were intensely stained, whereas the other epithelial cells in the gastric gland and pit exhibited only slight staining. Rapid-freezing and freeze-substitution immunoelectron microscopy revealed that Mn-SOD in parietal cells was mainly localized in mitochondria. Therefore, the large amount of Mn-SOD in parietal cells is due to the abundant mitochondria, in which Mn-SOD is considered to play important roles in protecting the ion pump and the cell itself from superoxide insult. Application of Triton X-100, cryosectioning, and the streptavidin-biotin system are needed to distinctly visualize Mn-SOD with our antibody. Treatment of the cryosections with Triton X-100 enhanced not only the immunoreactivity but also the false-positive staining, which showed a similar distribution pattern to that of Mn-SOD and thus made it difficult to determine the localization. The most plausible cause of the false-positive staining is thought to be endogenous biotin in the stomach, which survives paraformaldehyde fixation and is revealed by Triton X-100 treatment. Suppression of the endogenous streptavidin binding activity is important when cryosections, the streptavidin-biotin system, and Triton X-100 are employed.

Animals↗

PubMed1992

Synthesis of deuterium-labeled 16 alpha,19-dihydroxy C19 steroids as internal standards for gas chromatography-mass spectrometry.

[2 beta,7,7,16 beta-2H4]16 alpha,19-Dihydroxyandrost-4-ene-3,17-dione (14) and [7,7,16 beta-2H3]3 beta,16 alpha,19-trihydroxyandrost-5-en-17-one (16), with high isotopic purity, respectively, were synthesized from unlabeled 3 beta-(tert-butyldimethylsiloxy)-androst-5-ene-17 beta-yl acetate (1). The deuterium introduction at C-7 was carried out by reductive deoxygenation of the 7-keto compound 3 with dichloroaluminum deuteride and that at C-2 beta and/or C-16 beta by controlled alkaline hydrolysis of 16-bromo-17-ketone 11 or 12 with NaOD in D2O and pyridine. [7,7-2H2]3 beta-Hydroxyandrost-5-en-17-one (6), obtained from compound 1 by a five-step sequence, was converted to compound 14 or 16 by an eight-step or seven-step sequence, respectively. The labeled steroids 14 and 16 are useful as internal standards for gas chromatography-mass spectrometry analysis of the endogenous levels.

Androstenedione↗

PubMed1992

Effects of vasopressin and oxytocin on canine cerebral circulation in vivo.

In vivo experiments on the vasoactive effects of vasopressin and oxytocin on cerebral circulation were carried out in anesthetized dogs, using an electromagnetic flowmeter to measure vertebral blood flow and angiography to measure the internal diameter of the basilar artery. Direct bolus infusion of 1 pmol to 1 nmol of vasopressin or 10 pmol to 10 nmol of oxytocin into a femoral-vertebral artery shunt produced a dose-dependent decrease in vertebral artery blood flow without significantly affecting mean arterial blood pressure. Vasopressin was more potent than endothelin and neuropeptide Y, which have also been demonstrated to induce long-lasting decreases in vertebral artery blood flow. However, direct bolus infusion of vasopressin (100 pmol and 1 nmol) or oxytocin (1 nmol and 10 nmol) into the vertebral artery dilated major vessels including the vertebral, anterior spinal, and basilar arteries, as well as the circle of Willis and its main branches, while endothelin (1 nmol) and neuropeptide Y (5 nmol) caused no change in the diameters of major cerebral arteries. The V1 antagonist d(CH2)5tyrosine(methyl) arginine vasopressin suppressed the effects of both vasopressin and oxytocin. Vasopressin was over 10 times as potent as oxytocin in both assays. The vasodilatory effect of vasopressin, which may be mediated by an endothelium-dependent mechanism, was functionally damaged in dogs after experimental subarachnoid hemorrhage. These data suggest regional differences in the sensitivity and responsiveness of vasculature to vasopressin and oxytocin, and specifically that both peptides act through V1 receptors to decrease the resistance of large vessels and increase the resistance of small vessels.

Animals↗

PubMed1992

Serotonin-induced vasoconstriction in dog kidney.

Serotonin (5-HT 0.1 and 0.3 micrograms/kg) was injected as a bolus into the renal artery of anesthetized dogs. Renal blood flow (RBF) decreased initially after 5-HT injection and then increased. The 5-HT-induced decrease in RBF was potentiated during intrarenal infusion of a 5-HT1 and 5-HT2 antagonist methysergide at 3 micrograms/kg/min or of a 5-HT2 antagonist ketanserin (3-30 micrograms/kg/min), but methysergide at 30 micrograms/kg/min attenuated the decrease in RBF. The delayed increase in RBF was suppressed during ketanserin or methysergide infusion. In ketanserin-pretreated dogs, methysergide (3-30 micrograms/kg/min) dose-dependently suppressed the 5-HT-induced decrease in RBF. A 5-HT3 antagonist, ICS 205-930 (3-30 micrograms/kg/min), did not affect the 5-HT-induced RBF responses. A Ca2+ entry blocker CD-349 (30 and 100 ng/kg/min) and a Ca2+ release inhibitor TMB-8 (30 and 100 micrograms/kg/min) suppressed the 5-HT-induced decrease in RBF. These results suggest that 5-HT activates 5-HT1 receptors to induce vasoconstriction by mobilization of extracellular and intracellular Ca2+, but simultaneous activation of 5-HT2 receptors attenuates the vasoconstriction, probably by causing vasodilation in dog kidney.

Animals↗

PubMed1992

[Effect of chemotherapy on the prognosis of ovarian cancer].

Through the collaboration of 22 institutions nationwide, a total of 1,185 cases of ovarian cancer treated between January, 1980 and December, 1987, were investigated as to their prognosis from the aspect of the chemotherapeutic effect. (1) An excellent effect of the remission-induction chemotherapy was observed in a group receiving combination therapy with CDDP as the main ingredient. In particular a significant effect was seen in stages III and IV. In addition, the effect on the remaining tumors by diameter also showed a significant difference in cases of tumors of not less than 2 cm in diameter. (2) As to the effect on histological types, a comparison in stage III showed a favourable effect on endometroid, serous and mucinous adenocarcinomas, while no effect was observed in clear cell adenocarcinoma. (3) The effect of the remission induction chemotherapy did not always give rise to an improvement in the long-term prognosis of ovarian cancer, and the establishment of a therapeutic method aimed at the prevention of recurrence was desired. (4) To improve the long-term prognosis, intermittent (or cyclic) chemotherapy with CDDP as the main ingredient was found to be very effective, but maintenance chemotherapy with orally administered of 5-Fluorouracil or Tegaful was not effective. (5) The effect of the conventional immunotherapy was not observed at all.

Adenocarcinoma↗

PubMed1992

[Effects of epithelium removal and cooling on tracheal contraction in guinea pigs].

We investigated the effects of epithelium removal and cooling (32 degrees C, 27 degrees C, 22 degrees C) on isolated tracheal smooth muscle contraction induced by bethanechol (BCh), acetylcholine (ACh), histamine (Hist), and KCl in guinea pigs. The pD2 values (-logED50) increased in the epithelium damaged group compared with the intact group when ACh was administered at 37 degrees C, 32 degrees C, 27 degrees C and 22 degrees C, with histamine at all four temperature conditions, and with KCl at 37 degrees C, 32 degrees C and 27 degrees C. In both groups, the pD2 values for BCh, ACh, and KCl tended to decrease as temperature was lowered, and significant decrease in pD2 was observed at 27 degrees C. In contrast, the pD2 value for histamine tended to increase as temperature was lowered in every group. Concerning these agents, we conclude that epithelium removal and cooling exert neither significant nor consistent effect on tracheal epithelial function.

Acetylcholine↗

PubMed1992

[Successful intrauterine digoxin therapy for fetal complete atrioventricular block with endocardial cushion defect: a case report].

We report herein a case of fetal complete atrioventricular block accompanied with endocardial cushion defect, successfully diagnosed and treated, in utero, with transplacental digitalization. A 23-year-old Japanese woman, at 20 weeks of gestation, was referred to the Maternity and Perinatal Care Unit of Kyushu University Hospital because of fetal continuous bradycardia. B-mode scanning and dual M-mode echocardiography revealed that the fetus had complete atrioventricular block with endocardial cushion defect with a ventricular rate of 60 beats per minute. At 23 weeks of gestation, it was found that the fractional shortenings (FSs) in both ventricles and the ventricular rate had decreased, with an increase in pericardial effusion. Thus, we diagnosed the fetus as having cardiac failure. Transplacental digoxin treatment was started and continued for 10 weeks, after which fetal pericardial effusion, as well as FSs ameliorated. The pregnancy was interrupted by cesarean section at 33 weeks of gestation due to a decrease in FSs with an accumulation of fetal ascites. A 1780g female infant was delivered and a pacemaker was implanted surgically, immediately after birth. She is alive and well at the time of writing.

Adult↗

PubMed1992

[A group study on prognosis of ovarian cancer in Japan].

An assessment has been made, with the cooperation of 22 institutes, of 1,185 cases of ovarian cancer as subjects who were treated in the period from January, 1980, to December, 1987. As a result, (1) As for distribution by clinical staging at the initial examination, the cases in Stage III were the most numerous, followed by those in Stage I, and if classified according to the histological type, serous cystadenocarcinoma was the most frequently observed in Stage III, and undifferentiated and unclassified carcinomata were observed in Stages III and IV. (2) In the examination of prognostic factors, it was confirmed that the clinical stage, histological type and diameter of the remaining tumor after the initial operation were important factors. (3) A significant difference was observed between the grade of histomorphological differentiation and prognosis, the difference was chiefly due to the deviated distribution of clinical staging in each group of differentiation. (4) A favorable trend was observed in the prognosis by patient's age toward the younger layer. (5) When the starting time of the therapy is considered, a trend toward improvement has been seen year by year, and it is considered that the beneficial effect of chemotherapy with CDDP contributes to this.

Adult↗

PubMed1992

Rapid endothelialization of vascular prostheses by seeding autologous venous tissue fragments.

A method was developed to obtain rapid endothelialization of a fabric vascular prosthesis by seeding autologous venous tissue fragments into its wall. In an animal study, complete endothelialization was observed in the entire inner surface of the prosthesis within 2 weeks after implantation. A piece of peripheral vein was minced with scissors and then stirred into saline to create a tissue suspension. This suspension was enmeshed into the wall of a highly porous fabric vascular prosthesis by repeated pressurized injections with a syringe. The prostheses (7 mm inside diameter and 5.7 cm in length), seeded with tissue fragments, were implanted into the descending thoracic aorta of 25 dogs, and they were removed from 1 hour to 2 months after implantation. Twenty-five prostheses, preclotted with fresh blood, were used as control prostheses. In the seeded graft, a thin fibrin layer covered the inner surface just after implantation, but countless numbers of endothelial cells migrated from the fragments and came up to the luminal surface like multiple "mushrooms" under the fibrin layer. Smooth muscle cells made multiple layers underneath the endothelial cell layer. The healing proceeded equally at every part. By this active migration and proliferation, the inner surface was completely healed within 2 weeks.

Animals↗

PubMed1992

[A case of reoperation of coarctation of the aorta 13 years after corrective surgery of coarctation of the aorta, ventricular septal defect and pulmonary hypertension in infancy].

A 13-year-old boy underwent corrective surgery of CoA + VSD + PH at 50-day. Vascular murmur and hypertension was present so that he was admitted to our hospital. Systemic pressure was 164/106 mmHg (right arm) and systolic blood pressure at right leg was 70 mmHg. The systolic pressure gradient was 94 mmHg. The intracardiac pressure was within normal limit and there was no shunt. And the stenosis of descending aorta was present at the distal of subclavian branch and that pressure gradient was 76 mmHg. The diagnosis was established recurrent coarctation and operation was performed. The recurrent coarctation was 8 mm in diameter and longitudinal incision was made and woven Dacron patch aortoplasty was done. Aortic cross clamping time was 43 minutes. Postoperative clinical course was smooth. At 4 weeks after aortography was performed and no appreciable stenosis of the descending aorta was revealed. The pressure gradient decreased from 76 mmHg to 11 mmHg.

Adolescent↗

PubMed1991

A vacuolar ATPase and pyrophosphatase in Acetabularia acetabulum.

Vacuole-rich fractions were isolated from Acetabularia acetabulum by Ficoll step gradient centrifugation. The tonoplast-rich vesicles showed ATP-dependent and pyrophosphate-dependent H(+)-transport activities. ATP-dependent H(+)-transport and ATPase activity were both inhibited by the addition of a specific inhibitor of vacuolar ATPase, bafilomycin B1. A 66 kDa polypeptide present in the preparation cross-reacted with the anti-IgG fractions against the alpha and beta subunits of Halobacterium halobium ATPase and with the antibody against the A subunit (68 kDa subunit) of mung bean vacuolar ATPase. A 56 kDa polypeptide present in the vacuole preparation showed cross-reactivity with the antibody against the B subunit (57 kDa) of mung bean vacuolar ATPase but not with the anti-beta subunit of H. halobium ATPase. A 73 kDa polypeptide cross-reacted with the antibody against inorganic pyrophosphatase of mung bean vacuoles. These results suggest that vacuolar membrane of A. acetabulum equipped energy transducing systems similar to those found in other plant vacuoles.

Acetabularia↗