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Biomedical subjects

I Sasaki

Publications and source records attributed to I Sasaki.

At least 109 records · Page 6Linked to original sources
PubMed1994

Increased expression of mineralocorticoid receptor in human ileum after total colectomy: immunohistochemical and immunoblotting studies.

Aldosterone is known to regulate transmembrane ion transport and water absorption through its binding to mineralocorticoid receptor (MR) in the mammalian colon. A possible roles of aldosterone has been suggested in increased water absorption from remnant ileum in the patients with total colectomy. We, therefore, studied immunolocalization of MR in remnant ileal mucosa in the patients with total colectomy in order to study the role of aldosterone in water and sodium absorption in these patients. Immunohistochemical localization of MR was performed in ileal mucosa of 7 patients with total colectomy and 5 cases of normal ileum obtained from the resection of ascending colon due to carcinoma by using a polyclonal antibody raised against a mineralocorticoid receptor fusion protein as a primary antibody and a biotinstreptavidin system for immunostaining. Immunoblotting was also performed. Positive MR immunoreactivity was observed in both cytoplasm and nucleus of absorptive cells of ileum of total colectomy patients but not in control normal ileum. Immunoblotting revealed the presence of an approximately 100 kDa immunoreactive product corresponding to mineralocorticoid receptor. Aldosterone is considered to act on ileal mucosa following total colectomy and the aldosterone dependent sodium transport and water absorption may be accelerated in ileal mucosa after total colectomy, which is consistent with the postoperative decrease in the stool volume observed in these patients. In conclusion, increased expression of the mineralocorticoid receptor in remnant ileum may play an important role in intestinal adaptation in total colectomized patients.

Adenomatous Polyposis Coli↗
PubMed1994

Effects of substance P on gastric motility differ depending on the sites and vagal innervation in conscious dogs.

The effect of substance P on gastric motility was studied in conscious dogs by means of strain gauge force transducers chronically implanted on the gastric body, antrum, and a vagally-denervated fundic pouch. Intravenous infusion of substance P in the interdigestive state induced phasic contractions in the pouch and antrum. Atropine inhibited these contractions in the pouch and antrum. Hexamethonium enhanced substance P-induced contractions in the gastric antrum, but reduced those in the pouch. Pretreatment with phentolamine, propranolol, or naloxone did not affect substance P-induced contractions in the pouch and antrum. The intact gastric body scarcely reacted to substance P. Mean systemic blood pressure was lowered by substance P-infusion, but there was no dose-dependency in the reduction of the blood pressure, nor was it affected by the pretreatment with atropine or hexamethonium. These results suggest that 1) the vagal innervation influences the effect of substance P on motility in the gastric body, and that 2) substance P may stimulate postsynaptic excitatory cholinergic and presynaptic inhibitory neurons simultaneously in the gastric antrum.

Animals↗
PubMed1994

[Drug-induced organic mood disorders].

Firstly, we reviewed the drugs (ex, corticosteroid, interferon) which were thought to be related to organic mood disorders in the literature, and discussed a number of problems with assessment of drug-induced mental disorders. Next, we investigated 1) the antidepressant-induced switch rate from depression to mania and 2) the latency from administration to manic onset in three groups (Major depression: single episode, Major depression: recurrent, Bipolar disorder: depressed). Our data showed, 1) the switch rate was 17.2, 14.3, 32.0% and 2) the latency to onset was 69.9, 65.9, 37.1 days, respectively. The latency to onset showed no significant difference in three groups. (ANOVA, p < 0.05) Clomipramine, amitriptyline, imipramine, and dosulepin had the higher switch rate above 10%.

Antidepressive Agents↗
PubMed1994

[Organ failure due to hypoxemia, and effects of oxygen therapy--effects of hypoxemia on pulmonary hemodynamics, and improvement with oxygenation].

To investigate pulmonary hemodynamics in patients with chronic respiratory failure, we performed right heart catheterization and also examined the effects of oxygen inhalation. Thirty-three patients were studied. Their mean age was 65 +/- 10 years, and FEV1.0% and PaO2 on room air were 47 +/- 16% and 63 +/- 14 mmHg, respectively. mPAP was 27 +/- 10 mmHg, and 26 (78%) had pulmonary hypertension. Although PVR was abnormally high, CI and PCWP were within normal limits. PaO2 was significant Significantly correlated with mPAP and PVR. Although oxygen inhalation (28%) for 30 minutes significantly changed PaO2, PaCO2, and PvO2, it did not significantly affect mPAP, PVR, CI, or PCWP. These results suggest that short-term oxygen inhalation does not affect pulmonary hemodynamics in patients with chronic respiratory failure. Radionuclid ventriculography was also done to evaluate cardiac function in 16 patients before and after home oxygen therapy (HOT). Both right ventricular ejection fraction (RVEP) and left ventricular ejection fraction (LVEF) were significantly increased by HOT, and the significant correlation between RVEF and LVEF that had been observed before HOT disappeared. These results suggest cardiac function improved and that the interdependence between the right and left ventricle was eliminated by HOT.

Aged↗
PubMed1994

[Autonomic nervous function in progressive supranuclear palsy--comparison with Parkinson's disease and healthy controls].

This study evaluated the autonomic nervous function in 6 patients with progressive supranuclear palsy (PSP). The autonomic nervous functions in PSP patients were compared with those in 17 patients of Parkinson's disease (PD) and 9 age-matched healthy control subjects. Results were that all PSP patients and 59% of PD patients had sympathetic skin response (SSR) abnormalities. Significant abnormalities in cardiovascular response observed in PD patients suggested the presence of sympathetic and parasympathetic disturbances. There were no significant differences between PSP patients and control subjects in cardiovascular responses. But some of PSP patients showed abnormal cardiovascular responses compared with the results from the control subjects. In PSP patients mild disturbances in cardiovascular responses and sudomotor dysfunction were suggested. We consider that the high incidence of SSR abnormality is at least partially related to the presence of disturbances in the frontal lobes.

Aged↗
PubMed1994

[A case of adrenal pheochromocytoma with normotention and normal levels of urinary excretion of catecholamines].

A 62-year-old man was admitted to our hospital for further examination of right adrenal mass accidentally pointed out by ultrasonogram. He had no symptoms and no physiological abnormalities. Endcrinological examinations revealed normal adrenocortical function, excluding the possibility of functioning adrenocortical adenoma. Pheochromocytoma seemed to be also unlikely since 24-hr urinary excretion of catecholamines were within normal limits. The tumor was surgically removed and histopathologically diagnosed as pheochromocytoma. This case of adrenal incidentaloma is unique in that little sign of pheochromocytoma was presented before operation. The reasons were discussed especially in respect of tissue contents of catecholamines and opioid peptide in comparison with other cases with pheochromocytoma we had experienced.

Adrenal Gland Neoplasms↗
PubMed1994

[Multiple sclerosis with syringomyelia--case report].

A 32-year-old woman experienced subacute onset of weakness in her left leg, urinary retention and difficulty in extending her right middle and third finger. She subsequently suffered episodes of myelopathy, optic neuritis and cerebellar ataxia over a period of several years. Brain MRI showed multiple areas of high signal intensity on T2-weighted images, consistent with multiple sclerosis (MS). However spinal MRI revealed no abnormal findings. In her most recent episode, at age 40 she developed paraparesis. Neurologic examination revealed down beat nystagmus on gazing to the right, horizontal jerk nystagmus gazing to the left, weakness of the right middle and third fingers and paraparesis associated with spasticity of the right leg. Sensory disturbance below C3 and diminished vibration and position sense in both legs were also observed. The patient could not stand or walk, and urinary disturbance was present. Spinal MRI revealed syrinx formation at the level of vertebral bodies C2 to C6. The syrinx within the cervical cord diminished in size after four months, but the patient was unable to walk unaided and had moderate sensory disturbance as before. This finding suggests that the prognosis of MS with syrinx formation following repeated episodes of myelopathy is not always favorable. We believe that functional recovery in MS with syringomyelia is affected by the severity of the demyelination and/or gliosis caused by MS rather than by the presence of the syrinx.

Adult↗
PubMed1993

[Pure sensory stroke due to pontine lacunar infarction].

A 72-year-old woman presented a sudden onset isolated sensory deficit of medial lemniscal type in the right half of the body. MRI showed a small lacune in the left paramedian pontine tegmentum corresponding to the location of the medial lemniscus. MRI appeared to be most valuable in the topographic delineation of lacunar infarctions which were responsible for pure sensory stroke.

Aged↗
PubMed1993

Impact of stress on serum gastrin in Zollinger-Ellison syndrome.

We report an impressive case with Zollinger-Ellison syndrome (ZES), in which stress-induced sympathetic discharge influenced serum gastrin. Our patient was a 35-yr-old female who complained of frequent and massive vomiting (more than 4000 ml of gastric juice) which was aggravated especially by psychosocial stress. Basal hypergastrinemia (1900 pg/ml) was found after the admission. The most striking finding was that laboratory stress dramatically increased serum gastrin (from 1900 to 5400 pg/ml) and plasma noradrenaline (from 180 to 1130 pg/ml). Mental arithmetic stress further enhanced hypergastrinemia (5800 pg/ml) with a concomitant increase in plasma noradrenaline (1240 pg/ml). Neostigmine (10 micrograms/kg im) also increased serum gastrin up to 6100 pg/ml but propranolol (40 micrograms/kg i.v.) reduced these elevations (noradrenaline: 990 pg/ml, gastrin: 5000 pg/ml). In this case, the effect of stress on serum gastrin mimicked the effect of catecholamine infusion in ZES. These findings suggest that psychological stress induces serum gastrin secretion via beta-adrenoceptor with exacerbation of symptoms in some cases with ZES.

Adult↗
PubMed1992

An experimental study on the gastric acid and gut hormone secretion after pylorus preserving duodenectomy in dogs.

To clarify changes in gastric acid and gut hormone secretion after pylorus-preserving pancreaticoduodenectomy (PPPD), an experimental study was performed using a model of pylorus-preserving duodenectomy in dogs previously provided with Heidenhain pouch (HP). The duodenectomy involves resection of the duodenum and 10 cm of the proximal jejunum preserving 2 cm of juxtapyloric duodenum and round-shaped duodenal wall around pancreatic papilla. Reconstruction was done by anastomosing the rho-shaped jejunal loop to gallbladder, juxtapyloric duodenum and peripapillar round-shaped duodenal wall with ligation of the common bile duct. For these dogs, intravenous glucose tolerance test (IVGTT), oral glucose tolerance test (OGTT), meal ingestion test (TM) and histological studies of pancreatic specimen obtained at autopsy were performed investigating pancreatic, gastric acid and gut hormone secretion. Preservation of endocrine and exocrine pancreatic secretion after operation demonstrated our experimental model to be adequate for evaluation of the factor of duodenectomy in PPPD on gastric acid and gut hormone secretion avoiding the influences of changes in pancreatic secretion. Postprandial gastric acid secretion from HP did not change significantly after operation. Postprandial secretion of gastrin, glucagon, GIP and enteroglucagon did not alter significantly after operation. These results indicated that in the clinical PPPD procedure, preservation of more than 2 cm of duodenum from the pylorus produced neither postprandial gastric acid hypersecretion, which might be cause of postoperative stomal ulcer, nor any change of related gut hormone secretion.

Animals↗
PubMed1992

Long-term results of pylorus-preserving gastrectomy for gastric ulcer.

The postoperative results of pylorus-preserving gastrectomy (PPG) for gastric ulcer performed in 134 patients during the past 25 years (mean postoperative period, 16.6 years) were studied. The incidence of postoperative complications was low. Dumping syndrome occurred in only 4.4% and 0% of cases as assessed by questionnaire and interview, respectively. Four (5.4%) of 74 patients available for this study had ulcer recurrence. In one of these four patients concurrent gastroduodenal ulcer was suspected from preoperative gastric analysis. The site of recurrence was found in all cases to be the remnant antral gland area along the greater curvature between the proper gastric gland area and the duodenum. Basal and maximal acid outputs at the time of relapse were significantly higher in patients with recurrence than in patients without recurrence. The fasting and postprandial serum gastrin levels were high in one patient with recurrence, whose antrum was preserved as long as 3 cm proximal to the pyloric ring; this was longer than that described in our original method of PPG. In two other recurrent cases the serum gastrin levels were not different from those in nonrecurrent cases. Immunohistochemical examination of the residual antrum showed no increase in the G-cell density in patients either with or without recurrence. These results suggest that the long-term quality of life of patients treated with PPG remains favorable. Recurrence rate can be further reduced if PPG is strictly indicated for gastric ulcer only and carried out by meticulous surgical techniques. In the pathogenesis of the ulcer recurrence the role of gastrin release from the residual antral mucosa seems to be limited.

Adult↗
PubMed1992

Immunolocalization of mineralocorticoid receptor in human kidney, pancreas, salivary, mammary and sweat glands: a light and electron microscopic immunohistochemical study.

Using a polyclonal antibody against a synthetic fusion protein corresponding to 167 amino acids of the N-terminal region of the human renal mineralocorticoid receptor (MR), an immunohistochemical study was performed to investigate the intraglandular and intracellular localization of the receptor in human kidney, salivary gland, pancreas, mammary gland and sweat gland both at the light and electron microscopic levels. In the kidney, immunoreactivity was observed in distal convoluted tubules, branches of Henle's loop, and collecting tubules in the renal cortex, and papillary and Henle's loops' ducts in the renal medulla. No significant differences in the distribution of immunoreactivity were observed using different fixatives (10% neutral formalin, 100% methanol, 4% paraformaldehyde, PLP (periodate-lysine-2% paraformaldehyde) solution and Zamboni solution) and processing methods (paraffin embedding and frozen sectioning). Immunoreactivity in the kidney was observed in both the cytoplasm and nucleus, with cytoplasmic staining predominant, regardless of the methods of tissue preparation. Immunoelectron microscopy, employing a pre-embedding method, demonstrated the presence of immunoreaction precipitates in nuclei, endoplasmic reticulum, perinuclear cisternae, free cytoplasm and cell membranes. In nuclei, immunoreactivity was observed in euchromatin but not in heterochromatin, which is consistent with an association of MR with specific DNA regulatory elements located in transcriptionally active euchromatin. In other organs, MR was expressed in cells of the excretory ductal system where mineralocorticoids are known to play a role in electrolyte homeostasis.

Animals↗
PubMed1992

Technical note: development of a duodenal cannula for sheep.

A single T-shaped duodenal cannula of silicone rubber with a gutter-type small inner flange was developed for sheep. The barrel of the cannula was 24 mm long with an internal diameter of 12 mm. A polyester surgical mesh (100 mm x 100 mm) was connected to the barrel of the cannula as an anchor. Fibrous tissues grew on the polyester mesh anchor and adhered firmly to the serosa of the intestine, thus leaving no gap and, hence, preventing any leakage of intestinal contents from the side of the fistula. The small (24 mm in diameter) and thin (3 mm in thickness) outer flange of the cannula became buried in the wool and prevented any mechanical disturbance of the cannula by the activity of the animal. The elasticity of the silicone rubber prevented distortion of the duodenum around the barrel of the cannula. No erosion of the tissue between the inner flange of the cannula and the mesh was seen in postmortem observations.

Animals↗
PubMed1992

[Pulmonary function and exercise tolerance in patients treated with bone marrow transplantation (BMT)].

We assessed pulmonary function and exercise tolerance in 10 BMT patients. Their underlying disorders were as follows; chronic myeloid leukemia 5 cases, acute lymphoblastic leukemia 2 cases, aplastic anemia, acute myeloid leukemia and non-Hodgkin's lymphoma one case each. Their mean age was 26 +/- 9 years old. When the patients were healthy and free of serious complications and anemia, arterial blood gas examination, pulmonary function tests and incremental treadmill exercise test were examined repeatedly. Although %VC and FEV1.0% kept within normal range, PaO2 at rest, %DLCO, VO2max, VO2max/kg and O2-pulsemax remained low at one year after BMT. There were significant correlations between VO2max and O2-pulsemax [r = 0.955 (p < 0.001)], %VC [r = 0.758 (p < 0.02)], VE/VO2max [r = -0.749 (p < 0.02)] and delta SaO2/VO2/kg [r = -0.731 (p < 0.02)], suggesting that exercise intolerance in BMT patients may be based on both cardiac and gas exchange abnormalities. To evaluate cardiac dysfunction, we compared exercise parameters obtained at an exercise level of 75% predicted heart rate max in five age-matched normal subjects to those in six BMT patients who did not demonstrate desaturation during exercise. As a result, the mean values of VO2max/kg and O2-pulse/m2 in BMT patients were significantly lower than those in normal subjects, suggesting that cardiac dysfunction may be due to insufficiency of stroke volume during exercise. It is concluded that exercise intolerance in BMT patients may be mainly due to cardiac dysfunction.

Adolescent↗
PubMed1992

[Long-term effects and complications of home nasal CPAP therapy for obstructive sleep apnea patients].

We treated 23 patients with obstructive sleep apnea syndrome (OSAS) by nasal continuous positive airway pressure (NCPAP) at home, and examined the long-term compliance, clinical effects, and complications after NCPAP therapy. Nineteen patients continued and four patients discontinued the therapy during the mean observation period of 15 months, and the compliance was 83%. There was no significant difference in age, weight, and sleep data between the compliant group (C) and non-compliant group (NC). The causes of discontinuation of therapy were lack of adaptation to the apparatus (2 cases), improvement of clinical symptoms due to weight reduction (1 case), and induction of asthma attack (1 case). Disappearance of excessive daytime sleepiness, improvement of sleep quality, and disappearance of nocturia were observed in most cases, and disappearance of morning headache and improvement of sexual ability and emotional instability were also observed in several cases. Nine cases (39%) complained of discomfort due to the nasal mask and 6 cases (26%) complained of dryness of the mouth and nose, whereas 10 cases (43%) experienced no adverse effects. No serious complications were observed. These findings suggest that long-term home NCPAP is an effective and safe treatment for OSAS patients.

Humans↗
PubMed1992

[Ventricular performance during exercise in patients with chronic obstructive pulmonary disease (COPD)].

We assessed ventricular performance during exercise in 16 COPD patients and 8 normal control subjects by means of radionuclide equilibrium angiography using technetium-99m as a tracer. Supine exercise on a bicycle ergometer was performed until symptom-limited exhaustion. Data were accumulated for 300 heart beats at rest and 150 heart beats during exercise. We used the standard voxel count method to calculate the ventricular volumes. Age, FEV1.0%, %VC, PaO2 and PaCO2 of the COPD patients were 63 +/- 8 yr, 46 +/- 11%, 69 +/- 18%, 68 +/- 11 Torr and 44 +/- 7 Torr (mean +/- SD), respectively. Systolic dysfunction of both the left and right ventricles was well confirmed in the present study. In 12 patients who also underwent hemodynamic studies, resting total pulmonary vascular resistance index (TPVRI) and mean pulmonary artery pressure (Ppa) significantly correlated with right ventricular end-systolic volume index (RVESVI) obtained by RI angiography; gamma = 0.769 (p less than 0.01) and gamma = 0.631 (p less than 0.05), respectively. A significant relationship was also observed between left ventricular dysfunction and the degree of hypercapnia. In response to exercise testing, 10 of 16 patients exhibited insufficient augmentation of stroke volume, and both left and right end-diastolic volumes decreased in half of 10 patients. It is suggested that cardiac function may be disturbed by mechanical factors such as pulmonary hyperinflation in COPD patients.

Aged↗