Search PubMed⌕ Search

Biomedical subjects

H Saitoh

Publications and source records attributed to H Saitoh.

At least 235 records · Page 13Linked to original sources
PubMed1994

Effect of polylactic acid on osteoinduction of demineralized bone: preliminary study of the usefulness of polylactic acid as a carrier of bone morphogenetic protein.

To evaluate the usefulness of polylactic acid (PLA), a bioabsorbable and plastic polymer, as a carrier of bone morphogenetic protein (BMP), a preliminary study has been carried out to investigate any negative effect of PLA on osteoinduction of demineralized bone (DB). PLA (10,600 mol. wt) was mixed with DB particles (1-1.5 mm square) prepared from rat femurs and laid subcutaneously on the intercostal muscle of 4-week-old Wistar rats. The PLA/DB pellets were harvested at 2, 4, 8 and 24 weeks after the operation, and prepared for light microscopic examination. Histological examination revealed cartilage formation at 2 weeks and new bone formation at 4 weeks. Extensive bone and marrow formation were observed at 24 weeks. PLA was gradually absorbed and completely disappeared at 24 weeks to be replaced by connective tissue. These results demonstrate that PLA does not have a negative influence on the osteoinductive activity and that PLA could well be a promising bioabsorbable carrier of BMP.

Animals↗
PubMed1994

Right atrial myxoma with right to left shunt and coronary artery disease.

Surgical treatment of a right atrial myxoma with a right-to-left shunt and coronary artery disease was successfully performed in a 61-year-old man. The interatrial shunt occurred through a patent foramen ovale and was the result of a high central venous pressure due to tricuspid stenosis and regurgitation. Instead of right heart catheterization and cardioangiography, we chose an intraoperative blood-gas study to diagnose the intracardiac shunt. Preoperative polycythemia and hypoxemia were improved after removal of the tumor and closure of the patent foramen ovale.

Central Venous Pressure↗
PubMed1994

Cycle length-dependent action potential duration and contractile force at various [Ca2+]o in guinea pig papillary muscle.

This study was designed to determine the role of calcium in the cycle length-dependent changes in the action potential duration (APD) and the contractile force in guinea pig papillary muscle. APD correlated with the contractile force during the steady state, with [Ca2+]o ranging from 0.3-7.2 mM. High [Ca2+]o increased the force and shortened APD, while low [Ca2+]o had the opposite effect. During the steady state, as the cycle length of stimulation was decreased, the increase in the contractile force was inversely related to the increase in APD within a [Ca2+]o range of 0.9-5.4 mM and at diastolic intervals of < or = 600 msec. At longer diastolic intervals, the relationship between changes in contractile force and changes in APD was variable and non-linear at each [Ca2+]o. Changes in the postextrasystolic force were not related to APD. The phenomenon of APD overshoot i.e., an APD that was longer during short than during basic cycles, was observed at < 5.4 mM [Ca2+]o and was most pronounced at the lowest [Ca2+]o. Assuming that the contractile force reflects [Ca2+]i, we concluded that the cycle length-dependent APD curve during the steady state is influenced by [Ca2+]i in a manner consistent with the inverse relationship between APD and the contractile force.

Action Potentials↗
PubMed1994

[Hypotensive action of human renin inhibitor KRI-1314 in the common marmoset].

The possibility of using KRI-1314, a new cyclohexylnorstatine derivative, as an antihypertensive drug was examined using common marmosets. KRI-1314 strongly inhibited plasma renin activity (PRA) in both humans and marmosets, with a 50% inhibitory concentration of 4.7 x 10(-9) and 6.9 x 10(-9) M, respectively. In anesthetized marmosets, the increase in both blood pressure and PRA induced by bolus intravenous injection of RH-renin (0.15 microgram/kg) was suppressed by constant intravenous infusion of KRI-1314 (0.01 and 0.1 mg/kg/min) in a dose-dependent manner. In the sustained hypertension induced by continuous intravenous infusion of RH-renin (0.1 microgram/kg/min), a dose-dependent hypotensive response was produced by bolus intravenous injection of KRI-1314 (0.03-3 mg/kg). In the sodium-depleted model, whose PRA was increased by a two-week low-sodium diet coupled with furosemide loading, both intravenous injection (0.1-3 mg/kg) and oral administration (10 and 30 mg/kg) of KRI-1314 to anesthetized and conscious animals, respectively, lowered blood pressure dose-dependently with PRA suppression. The hypotensive activity of orally administered KRI-1314 (30 mg/kg) was almost equal to that of orally administered captopril (1 mg/kg). KRI-1314 did not affect heart rate in any of the experiments. These results indicate that the potent human renin inhibitor KRI-1314 may become an orally effective drug for treating renin-dependent hypertension.

Administration, Oral↗
PubMed1994

Effect of aibellin, a peptide antibiotic, on propionate production in the rumen of goats.

Aibellin was administered in feed to goats (16 to 18 kg of BW) for 12 d. At 80 mg/d, the molar percentage of propionate in rumen fluid increased significantly in 8 d, and the effect lasted for as long as 10 d after administration ceased. Total VFA concentration, protozoa numbers, and NDF digestibility were not depressed significantly at this dosage but were reduced at 100 mg/d with little further increase in the molar percentage of propionate. Therefore, the optimal dosage of aibellin was 80 mg/d under our experimental conditions. In contrast, monensin (30 mg/d) and gramicidin D (60 mg/d) decreased total VFA concentration and protozoa numbers when supplemented to obtain molar percentages of propionate comparable to 80 mg/d of aibellin. From these results, aibellin may be easier and safer to use than monensin and gramicidin D to modify rumen fermentation.

Animals↗
PubMed1994

[Efficacy of tonsillectomy for improving skin lesions of Pustulosis palmaris et plantaris--evaluation of 289 cases at the Department of Otolaryngology of Sapporo Medical University].

In recent years, Pustulosis palmaris et plantaris (PPP) has been described as one of the representative second lesions of focal tonsillitis in Japan. We selected 289 cases of PPP, treated with bilateral tonsillectomy at our department over the past 12 years for this clinical evaluation. In 211 of those 289 tonsillectomy cases, follow-up was done for more than 3 months after operation. Prior to tonsillectomy, 196 cases suffered from PPP only, 90 cases had the complication of osteo-arthral lesions such as sterno-costa-clavicular hyperosteosis (SCCH), rheumatoid arthritis, and soon, whereas only 3 cases showed simultaneous lesions of Psoriasis vulgaris. The efficacy of tonsillectomy for improving the skin lesions was classified into 6 grades, mainly based upon individual evaluation by each patient as follows; disappeared, remarkably improved, improved, slightly improved, unchanged, and worsened. According to our 211 cases, post tonsillectomy improvement of skin lesions was very obvious, with disappearance occurring in 54.3% of cases and remarkable improvement in 21.4%. Age of onset and the duration from onset to tonsillectomy showed no association with effectiveness. However, the shorter the duration from onset to tonsillectomy, the fewer days were required for improvement of the skin lesions. The rate of improvement of PPP rose in conjunction with the number of days after tonsillectomy. We conclude that it requires 12 months, at minimum, to determine the efficacy of tonsillectomy as a treatment for PPP.

Adolescent↗
PubMed1994

[Hematologic abnormalities in a patient with chronic myelogenous leukemia with advanced myelofibrosis were improved by G-CSF].

A 56-year-old woman was admitted with pyrexia, cough, and dyspnea on August 21, 1991. Physical examination revealed anemia in the palpebral conjunctivas and moist rales at the right lower lung field. Neither the Liver nor spleen was enlarged. Examination of the peripheral blood showed a hemoglobin level of 8.1 g/dl, a platelet count of 14.8 x 10(4)/microliters, and a white blood cell count of 2,800/microliters, with 7% blasts and 8% megakaryocytes. Tear drop-like erythrocytes, agranular neutrophils, and erythroblasts were also seen in the peripheral blood. Examination of the bone marrow showed 15% peroxidase positive blasts, and many micromegakaryocytes. Cytogenetic studies for bone marrow cells revealed the existence of the Philadelphia (Ph1) chromosome. Bone marrow biopsy showed normal cellularity with increase of megakaryocytes and advanced myelofibrosis. Breakpoint cluster region (bcr) rearrangement analysis using the peripheral blood mononuclear cells revealed M-bcr rearrangement. According to the Hannover classification for myeloproliferative disease, she was diagnosed as having CML with advanced myelofibrosis followed by CML with megakaryocytic increase. Since she had neutrocytopenia and severe infectious disease, she received a subcutaneous injection of 125 micrograms of G-CSF. Not only increase of the white blood cell count, but also disappearance of blasts, improvement of anemia, increase of the platelet count, and improvement of myelofibrosis were observed.

Blood Cell Count↗
PubMed1994

[Dynamic study of the hormonal levels and tumor markers after the first administration of long-acting LH-RH analogue in patients with prostate cancer].

The dynamics of hormonal levels and tumor markers after the first administration of long-acting luteinizing hormone-releasing hormone (LH-RH) analogue were evaluated in patients with prostate cancer. Eight patients with histopathologically proved prostate cancer who were previously untreated were studied. The surge in plasma testosterone was recognized in 7 patients after the first administration of a long-acting LH-RH analogue, and reached the highest level after the 3rd day in 6 patients and 14th day in 1 patient. The onset of flare-up reaction due to a transient increase in plasma testosterone was recognized in 3 patients, whose clinical symptoms and signs were increased bone pain in 2 patients and acute urinary retention in 1 patient. An abnormal level of serum prostatic acid phosphatase (PAP) and prostate specific antigen (PSA) was observed in 7 of the 8 patients before treatment. The serum PAP and PSA levels slightly increased after treatment in 4 and 3 patients, respectively. These findings suggest that the combination of estrogen or antiandrogen would allow a safer use of long-acting LH-RH analogue to prevent the risk of a flare-up reaction associated with the first administration of long-acting LH-RH analogue.

Acid Phosphatase↗
PubMed1994

[In vivo effects of anti-cam antibody on OA sensitized rats].

To determine the role of cell adhesion molecules, we evaluated the in vivo effects of anti-intercellular adhesion molecule-1 (ICAM-1) monoclonal antibody (1A29) and anti-leukocyte function associated molecule-1 (LFA-1) monoclonal antibody (WT-1) on ovalbumin (OA) sensitized rats. Both sneezing discharges and nasal rubbing movements after nasal OA challenge were significantly inhibited by these monoclonal antibody administrations (control vs treated group; 20.5 +/- 5.0 vs 7.0 +/- 2.9 times/minutes, p < 0.01 and and 56.8 +/- 7.1 vs 26.9 +/- 2.9 times/15 minutes, p < 0.01, for sneezing and rubbing, respectively). The number of eosinophils in nasal mucosa 24 hours after the challenge was also inhibited by the treatment (control vs treatment group; 108.8 +/- 27.3 vs 13.8 +/- 6.9 p < 0.01). These results suggest some pathophysiological roles of ICAM-1 and LFA-1 in nasal allergy.

Animals↗
PubMed1994

[The effects of diltiazem on neuromuscular transmission].

The effects of intravenous diltiazem (0.5 and 1.0 mg.kg-1) on muscle compound action potential (CAP) elicited from gastrocnemius muscle by sciatic nerve stimulation in cats were investigated. Analysis was performed on the amplitude of CAP, recovery curve (RC) and train-of-four ratio (TOFR). There was no response in any parameter after administering 0.5 mg.kg-1. On the other hand, diltiazem 1.0 mg.kg-1 produced significant depression only in the amplitude of CAP, but no change was observed in both RC and TOFR. It is concluded that approximately ten times the therapeutic dose of diltiazem is necessary to modify the neuromuscular transmission.

Action Potentials↗
PubMed1994

[Correlation between reperfusion ventricular fibrillation and postoperative enzyme release in coronary artery bypass grafting].

Twenty patients who had undergone elective coronary artery bypass grafting were divided into two groups according to the cardiac rhythms after aortic declamping. Eight patients had ventricular fibrillation (Vf group) and 12 patients had spontaneous resumption of heart beating in regular sinus rhythm (SPB group). In Vf group, percent CK-MB and absolute value of CK-MB on the first postoperative day showed significant increase compared with those of the SPB group (p < 0.01). Furthermore, duration of ventricular fibrillation after aortic declamping tended to be positively correlated (r = 0.7018) with absolute value of CK-MB on the first postoperative day, although this did not reach statistic significance (p = 0.0523). To the contrary, between the two groups no significant difference was found in percent LDH1, absolute value of LDH1, and ratio of LDH1 to LDH2 on the first and third postoperative day. It is suggested that ventricular fibrillation after aortic declamping plays a crucial role in increasing postoperative CK-MB level, and its duration is presumably correlated with the absolute value of CK-MB on the first postoperative day.

Adult↗
PubMed1994

[A case of left main coronary artery stenosis: additional insertion of saphenous vein graft to discontinue cardiopulmonary bypass].

A 62-year-old man with the lesions of the left main coronary artery and all the three vessels underwent a complete revascularization, in which the left internal mammary artery (IMA) was anastomosed to the large LAD. Although the operation proceeded uneventfully, the patient could not be weaned from the cardiopulmonary bypass (CPB). Another saphenous vein graft insertion into the LAD just distal to the IMA made it possible to discontinue the CPB. Postoperative angiogram revealed the patency of all grafts. But the IMA graft showed flow competition and string sign. We assume that failure to wean the patient from the CPB might be caused by hypoperfusion of the IMA graft, and in such a case, insertion of a saphenous vein graft is effective.

Anastomosis, Surgical↗
PubMed1994

[Surgical intervention to tuberculous pericarditis: a case report].

A 32-year-old man was hospitalized because of cardiac tamponade with the thickened visceral and parietal pericardial layers. Marked high level of adenosine deaminase activity (ADA) in pericardial fluid strongly suggested the diagnosis of tuberculous pericarditis, which was later assured by positive smear and culture of the pericardial fluid for Mycobacterium tuberculosis. Before rigid adhesion of the pericardial space was established, pericardiectomy was easily performed with satisfactory improvement of the hemodynamic status and physical symptoms of the patient. The present case suggests the efficacy of early surgical intervention to tuberculous pericarditis when it shows a sign of rapid progression to constrictive pericarditis. Furthermore, high ADA in pericardial fluid might be an useful diagnostic modality for tuberculous pericarditis.

Adenosine Deaminase↗
PubMed1994

[Adverse effect of internal thoracic artery steal on perioperative hemodynamic condition--a report of three cases].

In three patients who had suffered from perioperative hemodynamic deterioration after myocardial revascularization with an internal thoracic artery to the left anterior descending coronary artery (LAD), blood steal from the ITA into large side branches was strongly suspected. In two of them an intractable ventricular fibrillation occurred before closure of the chest. Additional insertion of saphenous vein graft to the LAD enabled them to get out of jeopardy. Postoperative angiographic studies demonstrated large pericardial branches which had several fistulous communications with the pulmonary circulation. The other suffered from anteroseptal myocardial infarction immediately after an uneventful operation. Postoperative angiography revealed an enlarged lateral costal branch which gave off four intercostal arteries. Careful and meticulous harvesting of the ITA is mandatory to avoid tragic consequences caused by its large side branches.

Hemodynamics↗
PubMed1994

[Development of enzyme-linked immunosorbent assay for biliary apolipoprotein A-I and a diurnal change of apolipoprotein A-I concentration in human bile].

Enzyme-linked immunosorbent assay for measuring biliary apolipoprotein A-I was established. Utilizing this assay, a diurnal change of apolipoprotein A-I concentration in hepatic bile obtained from percutaneous transhepatic drainage was investigated. A biliary apolipoprotein A-I concentration changed from time to time, and correlations between apolipoprotein A-I and total protein concentration, cholesterol concentration and lithogenic index, r = 0.873, 0.863 and 0.567 respectively, were observed. Moreover, biliary total protein concentration was closely related with lithogenic index (r = 0.671). These data suggest that hepatic lithogenic bile may induce apolipoprotein A-I secretion into hepatic bile.

Apolipoprotein A-I↗
PubMed1994

Identical blood pressure levels and slower heart rates among nurses during night work and day work.

To investigate the effects of shift work on circadian BP variation, ambulatory 24h BP monitoring was performed during the day shift and night shift on 17 normotensive nurses. On both shifts, BP and heart rate increased in the working phase and decreased during sleep. The mean 24h BP and heart rate were identical in the two shifts. During sleep, BP was lower and the heart rate was slower in the day shift (night sleep) perhaps because of deeper sleep than during daytime sleep associated with the night shift. During work, BP was identical but the heart rate was significantly slower during the night shift. These data suggest that the circadian BP variation is determined largely by the sleep-wakefulness cycle and that the heart rate is also influenced by the internal body clock.

Adult↗