Biomedical subjects

K Ohishi

Publications and source records attributed to K Ohishi.

At least 163 records · Page 9Linked to original sources

PubMed1993

Beneficial effect of the addition of nitroglycerin to the cardioplegic solution on the cold-stored reperfused isolated rat heart.

We discuss here the effect of the addition of trinitroglycerin to the cardioplegic solution on the isolated rat heart after eight hours of storage. This effect was evaluated by measuring cardiac function as well as myocardial calcium and enzymes. Male Wistar rats were divided into three groups based on the concentration of trinitroglycerine in the cardioplegic solution. In the control group, the fluid used was a crystalloid cardioplegic solution (K+ 25 mEq/L) without trinitroglycerin and for groups I and II, trinitroglycerin was added at concentrations of 2 micrograms/ml and 5 micrograms/ml, respectively. All hearts were arrested with the cardioplegic solution at 4 degrees C and then immersed for eight hours in Euro-Collins' solution at 4 degrees C. The postperfusion coronary flow showed higher rates for groups I and II than for the control group (p < 0.05), while the difference between groups I and II was not significant. In group I, the total concentrations of creatine kinase-MB, lactate and malondialdehyde after reperfusion showed the lowest levels; this group also had the lowest content of myocardial calcium. These results indicate that the addition of nitroglycerin, especially at a concentration of 2 micrograms/ml, to the cardioplegic solution elicits better cardiac function for immersed rat heart.

Animals↗

PubMed1993

The ability of Salmonella enteritidis isolated from chicks imported from England to cause transovarian infection.

S. Enteritidis HY-1 isolated during quarantine from chicks imported from England was used. Laying hens at the age of 34 weeks were inoculated orally with 10(10) organisms (10 birds), intramuscularly with 10(9) (5 birds), and intravenously with 10(9) (5 birds). Egg production did not change in hens infected orally, although it was reduced in hens infected intramuscularly for 2-3 weeks post inoculation. For one month, internally infected eggs of which the shells were not contaminated were found: one out of 65 eggs in hens infected orally and three out of 36 eggs in hens infected intramuscularly. This experiment demonstrated the ability of S. Enteritidis isolated from chicks imported from England to cause transovarian infection.

Animals↗

PubMed1993

Circadian rhythms of blood pressure and heart rate in patients with human T-lymphotropic virus type-I-associated myelopathy.

Noninvasive ambulatory blood pressure and heart rate monitoring were used to investigate cardiovascular dysfunction in patients with human T-lymphotropic virus type-I (HTLV-I)-associated myelopathy (HAM). The subjects were 23 patients with HAM, and 23 sex- and age-matched normotensive healthy volunteers (controls). Circadian rhythms of blood pressure and heart rate were present in both the HAM patients and controls. Amplitudes and the 24-hr mean systolic and diastolic blood pressures were significantly lower in the patients than in the controls. The 24 hr mean heart rate was significantly higher in the patients, the difference being particularly marked during the night. Differences in the acrophases of the systolic and diastolic blood pressures and heart rate between patients and controls were small but still significant. These results suggest that subclinical cardiovascular autonomic dysfunction is present in HAM patients.

Adult↗

PubMed1993

Transfusion-associated graft versus host disease following hepatectomy for hepatocellular carcinoma--a case report.

A case of transfusion-associated graft versus host disease (TA-GVHD) following hepatectomy for hepatocellular carcinoma is described in a 53 year-old male patient. The intraoperative bleeding was estimated to be 1220 ml, and he was transfused with 4 units of fresh whole blood. On postoperative day (POD) 12, a fever of 38 degrees C developed, followed by a systemic erythema on POD 14, and a marked progressive leukopenia starting from POD 19. The patient died of multiple organ failure (MOF) on POD 29. Just before death, the results of skin, bone marrow, and liver biopsies had no physical evidence of GVHD. TA-GVHD was found in the HLA typing of the patient's family. This TA-GVHD case was considered to be a reduced immunity due to severe surgical stress or preoperative transcatheter arterial embolization (TAE), in view of the fact that he was transfused with fresh whole blood during the operation. TA-GVHD has frequently been reported in patients after open heart surgery, but also after hepatectomy. It is therefore necessary to take all available means to prevent it by restricting the use of blood preparations as much as possible, and if hetero blood transfusions are performed, blood should be irradiated prior to transfusion.

Carcinoma, Hepatocellular↗

PubMed1993

Frequent gene expression of granulocyte colony-stimulating factor (G-CSF) receptor in CD7+ surface CD3- acute lymphoblastic leukaemia.

Gene expression of various cytokine receptors in CD7+ acute lymphoblastic leukemia (ALL) cells in relation to responsiveness to these cytokines was examined by reverse transcription polymerase chain reaction and Northern blot studies. Leukemic cells from all of seven CD7+ ALL patients examined fulfilled the criteria for ALL according to the FAB classification; surface CD3 was absent in all of these patients, while cytoplasmic CD3 and/or CD3 epsilon mRNA were found in all of them. Samples from six of the seven patients at initial disease expressed the granulocyte colony-stimulating factor receptor (G-CSFR) gene. Leukemic cells with G-CSFR transcripts from one patient at initial disease showed growth response to G-CSF in vitro, and those from two other patients became responsive to G-CSF at relapse. Neither in vitro nor in vivo myeloid differentiation was observed in any samples that responded to G-CSF. Interleukin 3R alpha (IL-3R alpha) gene was expressed in samples from one patient at initial disease and from two patients at relapse. GM-CSFR beta gene mRNA was detected in two patients with IL-3R alpha mRNA. Our results show that the leukemic cells in these CD7+ ALL patients frequently expressed G-CSFR as a functional property, thus calling attention to the appropriate clinical application of G-CSF for ALL patients.

Adolescent↗

PubMed1993

Determining the optimal time for endotracheal intubation during onset of neuromuscular blockade.

The disappearance of the response to single twitch stimulation (STS), double burst stimulation (DBS) and zero post-tetanic count (PTC) were evaluated to determine which best indicated the optimal time of endotracheal intubation during onset of neuromuscular blockade induced by vecuronium (0.08 mg kg-1) in 199 patients under thiopentone and halothane anaesthesia. Evaluations were performed by mechanomyographic and manual methods using a Myograph and a peripheral nerve stimulator. The study consisted of six parts. In part 1 (n = 30) and part 2 (n = 30), the response to STS (0.1 Hz) were evaluated mechanically and manually, respectively. In part 3 (n = 64), post-tetanic count (PTC) changes were evaluated mechanically. In part 4 (n = 30) and part 5 (n = 30), response to DBS were evaluated mechanically and manually, respectively. Intubation was performed immediately after obtaining zero PTC, or absence of response to STS (0.1 Hz) and DBS, and the intubation score was determined. In the control group of patients, intubation was performed under the same anaesthetic conditions as in parts 1-5 but without the administration of any muscle relaxant. The time from administration of any muscle relaxant. The time from administration of vecuronium until disappearance of response was 2.16 +/- 0.56, 2.49 +/- 0.68, 2.04 +/- 0.29, 2.20 +/- 0.53, and 2.97 +/- 0.61 min in parts 1-5, respectively. Excellent intubation conditions were not established in any of the control patients, and in 50.0, 70.0, 55.0, 70.0 and 90.0% of the patients in parts 1-5, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Clinical study of 47 patients with reoperation after open mitral commissurotomy.

Mitral lesion in 47 patients who received reoperation after an initial open mitral commissurotomy (OMC) for mitral stenosis (MS) was studied. The diagnosis before OMC consisted of pure MS in 38 patients, with mild mitral regurgitation (MR) in 8 and with moderate MR in 1. At OMC the diameter of the mitral orifice was a mean of 1.3 +/- 0.5 cm and a mobile cusp was found in 12 and a thickened cusp in 35 patients. Subvalvular fusion was seen in 15 patients, calcification of cusp or subvalvular region in 10 and left atrial thrombus in 6. After OMC, the diameter of the mitral orifice was opened to a mean of 3.2 +/- 0.3 cm. The interval between the initial operation and the time of reoperation was a mean of 124 months. The mitral lesion necessitating reoperation was MS in 18, moderate to severe MR in 10, and MSR in 19. At reoperation the mitral orifice ranged in diameter from 0.8 to 4.2 cm (mean, 2.3 +/- 0.8 cm). There was no correlation between the occurrence of MR or restenosis and the subvalvular division at initial OMC. Left atrial thrombus was identified in four and calcification in 17 patients. At reoperation 46 patients received mitral valve replacement, while only 1 received a second OMC. The removed valve showed no pathological findings of active rheumatic lesion but more severe calcification and hyalinization of the valve than those at initial operation. There were three early deaths (6.4%) after reoperation. The recurring mitral lesion seemed to consist of deteriorated pathological changes of the valve and MR and thus mitral valve replacement was recommended to provide a favorable operative result for non-flexible lesion after OMC.

Adult↗

PubMed1993

Doppler echocardiographic evaluation of St. Jude Medical valves in the tricuspid position.

Sixteen of 20 patients who underwent tricuspid valve replacement with a St. Jude Medical valve at our hospital were followed for three to 164 months. Doppler echocardiographic and cineradiographic examinations of the replacement device were performed in 13 patients. There were six males and seven females in the study, with a mean age of 41.9 years. A St. Jude Medical prosthesis had also been implanted in the mitral or mitral and aortic positions of eight of these thirteen patients. Ten patients had normally functioning valves in the tricuspid position and three were diagnosed as malfunctioning. The peak velocity in those patients with normally functioning tricuspid valves was 1.3 +/- 0.2 m/sec. The calculated peak and mean pressure gradients were 6.7 +/- 1.9 mmHg and 2.6 +/- 1.1 mmHg, respectively, and the mean pressure half-time was 120 +/- 22 msec. All normally functioning valves in the tricuspid position had peak velocities of less than 1.55 m/sec, and peak and mean pressure gradients of less than 9.6 mmHg and 5 mmHg, respectively, with the pressure half-time being less than 140 msec in all cases, except for one of the three Doppler studies performed in one patient. However, three Doppler studies performed in two patients with a malfunctioning tricuspid valve revealed peak velocities, peak and mean pressure gradients and pressure half-times which were above these values. After replacement of the malfunctioning valve, or thrombolysis, all of the Doppler-derived values returned to the range found in normally functioning valves.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

[A case of discrete type of subpulmonary stenosis].

We reported a 8-year-old girl having discrete type of subpulmonary stenosis. This patient was associated with atrial septal defect (ASD), valvular pulmonary stenosis, and persistent left superior vena cava (PLSVC). The incidence of this type of subpulmonary stenosis is less frequent than that of subaortic lesion. ASD was closed by the autologous pericardium and a transannular patch was used for enlargement of the right ventricular outflow tract followed by commissurotomy of the pulmonary valve and resection of subpulmonary discrete lesion. She was uneventful and postoperative pulsed doppler echocardiogram showed good results.

Child↗

PubMed1993

Clinical evaluation with exercise performance in twenty patients who underwent coronary artery bypass grafting with both the gastroepiploic and internal thoracic arteries.

Postoperative exercise performance was evaluated in 20 patients who underwent complete coronary revascularization with simultaneous right gastroepiploic artery and internal thoracic artery grafts for ischemic heart disease and exhibited patency of all grafts on postoperative angiograms. Three patients received only arterial grafts, and 17 simultaneously received a saphenous vein graft. Forty five right gastroepiploic artery grafts were harvested during this study, but two were not used because of foci of severe calcification. The right gastroepiploic artery was grafted to the distal right coronary artery in 17 patients and to the distal obtuse marginal branches in three patients, accompanied by an internal thoracic artery graft to the left anterior descending artery in seventeen, to the diagonal branch in three, and to the proximal right coronary artery in one patient. A postoperative exercise test with a bicycle ergonometer was administered 6 to 12 weeks after the operation, and the results are reported after conversion into metabolic units. The preoperative exercise test resulted in 3.6 +/- 1.9 metabolic units for 18 patients tested, and the postoperative metabolic units were 7.8 +/- 1.3 for 20 patients. Left ventricular wall motion was analyzed by regional ejection fraction before and after coronary artery bypass grafting in 14 patients who received an right gastroepiploic artery graft for the right coronary system. The mean regional ejection fraction of the posterobasal or diaphragmatic wall was 28.0% or 28.2% before operation and improved to 43.1% or 43.2% after coronary artery bypass graft, respectively. The flow of right gastroepiploic artery seemed to distribute adequately to the revascularized area. Long-term results have not yet been proved; the use of simultaneous right gastroepiploic artery and internal thoracic artery grafts, however, thus produced excellent results, as seen from improvements in both left ventricular wall motion and early postoperative exercise performance.

Adult↗

PubMed1993

[Left atrial free-floating ball thrombus in a patient without mitral valve disease].

A free-floating ball thrombus in the left atrium is a rare clinical problem with potentially catastrophic consequences. Thus, early diagnosis and prompt surgical intervention are mandatory. This report dealt with a free-floating ball thrombus in the left atrium in a case without mitral valve disease. A 82-year-old woman was presented with dyspnea, hypotension, and fever. On admission she had cardiac arrhythmia, but had no cardiac murmur. The electrocardiogram revealed atrial fibrillation. Chest X-ray examination showed marked cardiomegaly (cardio-thoracic rate; 94%) without evidence of pulmonary venous congestion. Coagulation studies revealed decreased coagulability. Transthoracic and transesophageal echocardiograms showed retention of pericardial effusion, and a free-floating ball thrombus in the dilated left atrium. Thickening, calcification, and restricted motion of the mitral leaflets were not observed by echocardiography. Removal of the free-floating ball thrombus in the left atrium was successfully performed on the emergency basis. The intact mitral valve was also confirmed at operation. The patient recovered uneventfully. Usefulness of echocardiography, particularly transesophageal echocardiography, for precise diagnosis and intraoperative management of a free-floating ball thrombus in the left atrium is discussed.

Aged↗

PubMed1992

The role of 5'-methylthioadenosine on rat calvaria cell differentiation.

The role of 5'-methylthioadenosine (MTA), formed during the process of polyamine biosynthesis, on differentiation of osteoprogenitor cells was assessed by its effects on alkaline phosphatase (ALP) activity, bone nodule formation and osteopontin contents of cultured rat calvaria (RC) cells. These three markers were stimulated by exogenous MTA and were depressed by 5'-difluoromethylthioadenosine (DFMTA), a synthetic inhibitor of MTA phosphorylase, which cleaves MTA to adenine and 5-methylthioribose-1-phosphate. 5-Methylthioribose and 2-keto-4-methylthiobutyrate, metabolites of 5-methylthioribose-1-phosphate, had no effects on ALP activity and bone nodule formation in the presence or absence of DFMTA. On the other hand, adenine enhanced ALP activity, bone nodule formation and osteopontin contents in mineralized nodules and also partially reversed DFMTA-induced inhibition of these three markers. MTA, its metabolites and DFMTA did not affect the growth of RC cells under these culture conditions. These results suggest that adenine formed from MTA is important in the differentiation of RC cells.

Adenine↗

PubMed1992

Complete correction of the tetralogy of Fallot in adults using separated extracorporeal circulation to block intrathoracic collateral circulation and improve perfusion of the renal vasculature.

During the last 10 years, complete correction of the tetralogy of Fallot (TOF) has been performed on 28 adult patients using the "separated extracorporeal circulation" (separated ECC) technique developed by us. In addition to the usual ascending aortic and dual right arterial cannulations for ECC, the separated ECC also involved femoral arterial cannulation and the insertion of a catheter with two balloons via the other femoral artery. Flow via the ascending aorta and femoral artery were maintained separately during ECC. The urine output during separated ECC was significantly better than that during ordinary ECC (P < 0.01) and the operative field for intracardiac correction was clearer as a result of blocking the collateral circulation. Thus we believe separated ECC to be a superior method for total correction of TOF in adults, which may enhance the operative outcome.

Adult↗

PubMed1992

Morphological and functional study of free arterial grafts.

Morphological and functional changes of free arterial grafts in dogs were studied for 3 weeks after implantation and the changes were compared to those in implanted free vein grafts. In the arterial grafts, endothelial cells with abundant pinocytotic vesicles and some cytoplasmic folds were observed by transmission and scanning electron microscope and cell detachment was seen only at the site of anastomosis, while most cells were detached in the vein grafts. The site of mechanical damage in the arterial grafts was covered by regenerated endothelial cells which showed similar morphological findings to the normal arterial endothelial cells. In contrast, regenerated cells in the vein grafts started to cover the denuded area 7 days after the implantation and had completely covered it by 3 weeks. Prostacyclin was produced more abundantly in arterial grafts than in vein grafts at any phase after implantation. The level of prostacyclin production was between 30 and 40 pg/mg in any phase after implantation of free arterial grafts, while in vein grafts the level was 2.5 pg/mg at the day of implantation and increased to 13.6 pg/mg at 21 days. This study showed that the endothelial cells were well preserved and the level of prostacyclin production was high in the arterial grafts, and thus the grafts seemed to show potent anti-thrombogenicity after implantation. Although late changes in arterial and vein grafts were not investigated in this experimental protocol, these results may suggest that the arterial graft is superior to the vein graft even in the early period after its implantation as a free graft.

6-Ketoprostaglandin F1 alpha↗

PubMed1992

Long-term follow-up results after reconstruction of the mitral valve by leaflet advancement.

In this study, we discuss the clinical results of mitral leaflet advancement performed on 29 patients over the past 10 years and attempt to determine the indication. Preoperative diagnosis of mitral valve lesion consisted of mitral regurgitation in 21 patients and mitral stenosis in 8 patients. Mitral valve repair was applied to the anterior mitral leaflet in 2, the posterior mitral leaflet in 25, and bilateral leaflets in 2 patients. Reoperation was performed on 13 patients, and 1 patient died of renal failure immediately after reoperation. No reoperation was needed for 96.6% of the patients at 1 year, 89.5% at 5 years, 75.0% at 8 years, 63.8% at 10 years, and 52.6% at 15 years postoperatively. At reoperation, the repaired mitral leaflet was found to be calcified in 3 patients more than 9 years after the initial operation. Of the 12 survivors without reoperation, mitral stenosis associated with regurgitation was obvious in 6 patients. Of the 21 patients with preoperative mitral regurgitation, 90.0% showed no deterioration at 5 years, 79.7% at 8 years, and 69.1% at 10 years. On the other hand, for the 8 patients with mitral stenosis, the rates were 87.5% at 1 year, 62.5% at 5 years, 50.0% at 8 years, and 25% at 10 years. Our results suggest that mitral leaflet advancement shows satisfactory results in patients with mitral regurgitation but is not successful for patients with mitral stenosis in the long term because the repaired valve tends to be stenotic in the late postoperative period.

Adolescent↗

PubMed1992

Structural alterations of the p53 gene in human leukemias.

We have investigated alterations of the p53 gene in human leukemias by polymerase chain reaction-mediated restriction fragment length polymorphism analysis. This method detects the codon 72 polymorphism of the p53 gene, allowing identification of loss of heterozygosity (LOH) of the p53 gene. In this study, at least two specimens were obtained from each patient to compare the allele status at different points of clinical course. Of 21 cases examined 7 were heterozygous at this polymorphic site and were evaluable for LOH study. Only one patient of Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) lost the heterozygosity in the specimen of her last relapse. Leukemic cells from her repeated relapses including the last one revealed to have the clonally rearranged immunoglobulin H chain gene of the same size, indicating that alteration of the p53 gene in this patient might account for the lethal relapse as a clonal evolution event. Northern-blot analysis of the p53 gene showed that one case of CD7(+) ALL had altered p53 mRNA. Overall, it is demonstrated that alterations of the p53 gene might be involved in the pathogenesis or progression of at least some human leukemias, although the alterations in leukemias seemed to be not as frequent as in solid tumors.

Base Sequence↗

PubMed1992

Antigenic analysis of Clostridium chauvoei flagella with protective and non-protective monoclonal antibodies.

Five monoclonal antibodies (mAbs) directed against the flagellin of Clostridium chauvoei were used to analyse the structural and antigenic characteristics on the bacterial flagellar surface. Immune electron microscopy showed that three protective mAbs recognized the surfaced-exposed epitopes on the flagellar filament of this bacteria. In contrast, two non-protective mAbs recognized internal epitopes of the flagellar filament. These findings have been confirmed by ELISA using mAbs absorbed with whole cells of C. chauvoei possessing flagella. Competitive binding assays showed that protective mAbs indicated reciprocal competition, while each of the non-protective mAbs had topographically distinct epitopes. Moreover, immunoblotting analysis with cyanogen-bromide-cleaved flagellin showed that protective mAbs may preferentially recognize conformational epitopes, whilst one of the non-protective mAbs may recognize a linear and conformation-independent epitope in the flagellin of C. chauvoei.

Antibodies, Monoclonal↗

PubMed1992

Augmentation of bovine leukemia virus (BLV)-specific lymphocyte proliferation responses in ruminants by inoculation with BLV env-recombinant vaccinia virus: their role in the suppression of BLV replication.

Lymphocyte proliferation responses were investigated in sheep and cattle, in which the replication of bovine leukemia virus (BLV) had been known to be suppressed by inoculation with recombinant vaccinia virus (rVV) expressing BLV envelope glycoprotein (gp60). Enhanced lymphocyte proliferation responses were observed in animals inoculated with rVV, regardless of whether they were naive or BLV carriers. These responses were roughly inversely correlated to the growth of BLV in the peripheral blood leukocytes. In contrast, there was no apparent correlation between humoral immune response and BLV growth. Based on these results, it was suggested that rVV rendered its suppressive effect of BLV replication primarily via augmentation of cell-mediated immunity.

Animals↗