Search PubMed⌕ Search

Biomedical subjects

S Ikeda

Publications and source records attributed to S Ikeda.

At least 505 records · Page 28Linked to original sources

Occupational exposure in pediatric cardiac catheterization.

Radiation doses to staff involved with pediatric cardiac catheterization were measured using thermoluminescent dosimeters in 18 procedures. The average doses to the lens and thyroid, and the effective dose per procedure to the main operating physicians was 88, 180, and 8 microSv, respectively; to assistant physicians, 23, 51, and 2 microSv; and to technicians, 23, 27, and 2 microSv. In some procedures, the dose to the technician's hand approached 1,500 microSv. The doses received by physicians were proportional to cineangiographic time but with no correlation with integrated currents. The number of procedures which may be performed in a year by individual staff members was estimated to be 430 and 2,780 procedures for physicians and assistants, respectively. It was suggested that the front of the neck is an adequate position for the dosimeter to measure doses during pediatric catheterization.

Adolescent↗

Keratin 14 gene mutations in patients with epidermolysis bullosa simplex.

Mutations in genes encoding the keratin intermediate filaments expressed in basal cells have been identified in some families with epidermolysis bullosa simplex as the proximate cause of the fragility. We have systematically scanned genomic sequences of one of these keratins, keratin 14, for mutations in patients from 49 apparently independent kindreds using single-strand conformation polymorphism analysis. The ten mutations identified are clustered at three sites--the ends of the helices and the L12 linker region, mutation sites that have been identified in past, more limited studies. Early onset of blistering in these ten families is correlated with more widespread distribution of lesions.

Age of Onset↗

Adult hepatoblastoma: case report and review of the literature.

We report a case of hepatoblastoma in a 24-year-old woman. The tumour was removed by an extended right lobectomy after transcatheter hepatic arterial embolization. A survey of the literature revealed 31 cases of adult hepatoblastoma. According to these reports there are no characteristic clinical features of the tumour, making a correct diagnosis before surgery or autopsy extremely difficult. Complete removal of the tumour is the only treatment which is potentially curative provided that lesion is confined within the liver capsule.

Adult↗

Filtration of human seminal specimens using LeukoSorb leukocyte-retention medium.

OBJECTIVE: To compare LeukoSorb filtration with Percoll centrifugation in preparing sperm. METHODS: Each of 26 human seminal specimens were analyzed before and after two preparation methods. RESULTS: In normospermic specimens (n = 11), LeukoSorb produced higher results than Percoll did with regard to mean percentage of motility (72.7% vs 59.2%), total swollen sperm in a hypo-osmotic swelling test (84.8% vs 59.0%), (g)-type swollen sperm (37.8% vs 23.4%) and tail abnormality (20.4% vs 10.1%). In asthenospermic specimens (n = 15), LeukoSorb produced higher results than Percoll did with regard to mean percentage of motile sperm recovery (22.2% vs 10.1%), motility (46.9% vs 23.2%), viability (75.6% vs 54.7%), total swollen sperm (84.8% vs 59.0%) and tail abnormality (42.2% vs 24.3%), although the mean percentage of head abnormality was lower with LeukoSorb than with Percoll (30.6% vs 40.2%) vs 40.2%). In pyospermic specimens (n = 10), the mean concentration of round cells after LeukoSorb decreased significantly more than with Percoll (p = 0.029). The filtration time correlated with the total sperm concentration. CONCLUSION: LeukoSorb filtration is useful for preparing asthenospermic and pyospermic seminal specimens.

Centrifugation↗

Pharmacology of a non-selective ETA and ETB receptor antagonist, TAK-044 and the inhibition of myocardial infarct size in rats.

1. The aims of the present study were to characterize the pharmacological profile of a new endothelin (ET) receptor antagonist, TAK-044 and to consider whether it limits the extension of myocardial infarct size in rats. 2. Binding of [125I]-ET-1 to ET receptors on rabbit ventricular and cerebellar membrane fractions was inhibited by TAK-044 with IC50 values of 3.8 nM and 130 nM, respectively. 3. It inhibited ET-1, ET-2 and ET-3-induced vasoconstriction of porcine isolated coronary arteries in a competitive (ET-1, ET-2) and a non-competitive (ET-3) manner. 4. In the rat in vivo, the ET-1-induced blood pressure changes including transient hypotension followed by sustained hypertension, were inhibited by TAK-044 (0.1-10 mg kg-1, i.v.) in a dose-dependent manner. 5. Acute myocardial infarction induced by 1 h coronary occlusion followed by 24 h reperfusion in rats caused an infarct size of 60 +/- 2% (n = 12) of the area-at-risk by weight. 6. Intravenous injection of TAK-044 10 min before coronary occlusion reduced the infarct size in a dose-dependent manner: 32% and 54% reductions at 1 and 3 mg kg-1, respectively. 7. TAK-044 administered 10 min before or 1 h after reperfusion (1 mg kg-1, i.v.) showed similar inhibitory effects: 34% and 23% reductions, respectively. 8. We conclude that TAK-044 is an ETA/ETB receptor antagonist which shows strong inhibitory effects on the extension of myocardial infarct size after coronary artery occlusion-reperfusion in rats.

Animals↗

Ventilatory and pulmonary vascular responses to acute hypoxia are nonuniform in healthy man.

The present study was undertaken to examine the pulmonary vascular and ventilatory responses to acute hypoxia in healthy individuals. Pulmonary hemodynamics and minute ventilation (VE) were serially measured during inhalation of 13% O2 for 15 min. There was a wide variability in the pulmonary vascular response to acute hypoxia, and a significant negative correlation between the initial increase in VE after the start of hypoxia (delta VE) and the percent increase in mean pulmonary arterial pressure (r = -0.646; p < 0.01). The fall in arterial oxygen tension significantly decreased in response to an increase in delta VE. These results support the view that a blunted ventilatory response to acute hypoxic stimulation enhances alveolar hypoxia, thereby favoring the constriction of pulmonary vasculature. Thus, our results suggest that the ventilatory response to acute hypoxia plays a significant role in the pulmonary vascular response to acute hypoxia.

Acute Disease↗

Assessment of right ventricular diastolic function by pulsed Doppler echocardiography in chronic pulmonary disease and pulmonary thromboembolism.

We evaluated right ventricular (RV) diastolic performance in 12 healthy subjects (control), 25 patients with chronic pulmonary diseases (CPD) and 6 patients with chronic pulmonary thromboembolism (PTE). Flow velocity patterns were determined by the pulsed Doppler technique. The values determined included acceleration time (AT), deceleration time (DT), and the ratio of the atrial contraction wave (A) to the rapid filling wave (R) (A/R ratio) from flow velocity patterns in the RV inflow tract. DT was significantly prolonged in the CPD and PTE groups compared with the control group, indicating dysfunction during the early (middle) filling period. The prolongation was marked in those patients with pulmonary hypertension. The A/R ratio was significantly higher in the CPD and PTE groups than in the control group, indicating a decrease in RV compliance. The A/R ratio increased slightly with the increase in the end-diastolic volume index. These results suggested that the pressure overload plays an important role in RV diastolic dysfunction in patients with pulmonary disease, and that preload contributes to the dysfunction.

Aged↗

Interpretation of extravascular thermal volume of the lung in patients with chronic pulmonary diseases.

To understand the significance of measured extravascular thermal volume of the lung (ETVL) in chronic pulmonary diseases, we measured ETVL using the double-indicator dilution technique in 17 emphysematous patients and 15 patients with pulmonary fibrosis. The level of ETVL in emphysema is significantly correlated with parameters reflecting the severity of the disease, including FEV1.0% (r = 0.54, p < 0.05), DLCO/VA (r = 0.54, p < 0.05), PaO2 (r = 0.61, p < 0.01), and mean pulmonary artery pressure (r = -0.61, p < 0.01). In pulmonary fibrosis, a significant inverse correlation was found between ETVL and PaO2 (r = -0.64, p < 0.02), DLCO/VA (r = -0.58, p < 0.05), and %VC (r = -0.61, p < 0.02). The mean level of ETVL in both groups of patients was lower than previously reported normal values. These results suggest that ETVL may reflect the decrease in pulmonary vasculature in emphysematous patients, while it may signify a decrease of pulmonary vasculature and increased volume of pulmonary interstitial tissue surrounding the pulmonary vasculature in pulmonary fibrosis. We conclude that ETVL may represent a good estimate of the condition of the pulmonary vasculature and interstitial tissue volume in patients with chronic pulmonary diseases.

Aged↗

Monitoring of nocturnal oxygen desaturation using pulse oximeter and apnomonitor in patients with chronic pulmonary disease.

The relationship between the degree of nocturnal oxygen desaturation (NOD) and pulmonary hemodynamics, pulmonary function tests, and resting awake blood gases was evaluated in patients with chronic pulmonary diseases (CPD). The severity of NOD correlated with the degree of impairment of pulmonary hemodynamics, but not with pulmonary function tests or resting awake blood gases. NOD was markedly alleviated by oxygen inhalation in CPD patients who did not develop sleep apnea.

Aged↗

Cytoplasmic body myopathy with hypertrophic cardiomyopathy.

A patient with cytoplasmic body myopathy presented muscle hypotonia from birth and developed progressive muscular atrophy and weakness, scoliosis, contracture of joints and cardiorespiratory failure. At the age of 17, he died of heart failure. Post mortem examination revealed severe hypertrophy of cardiac walls and generalized muscular atrophy. Microscopic examination showed many cytoplasmic bodies in skeletal muscle fibers and myofiber disarray in myocardium. No cases of cytoplasmic body myopathy with hypertrophic cardiomyopathy have been reported previously. It is suggested that the Z-line component is related to the formation of the cytoplasmic body in skeletal muscle and disarray in the cardiac muscle.

Adolescent↗

[UFT/CDDP preoperative chemotherapy for progressive gastric cancer--histological antitumor effects and thymidylate synthase inhibition rate].

Pre-operative chemotherapy with concomitant use of UFT and CDDP (UFT: oral administration of 400 mg/day for 2 weeks till one day before operation, CDDP, one intravenous drip of 40 mg/m2 one week before operation) was used for 24 untreated cases of advanced stomach cancer diagnosed as resectable pre-operatively, and the histological antitumor effect analyzed in dissected preparation and the thymidylate synthase inhibition rate (TSIR: %) in tumor tissue were examined. The average administration dose of CDDP was 61.1 mg/body, and the average total administration dose of UFT was 5.0 g/body. The histological antitumor effect was grade 0 in 8 cases (33.3%), grade 1a in 10 cases (41.7%), grade 1b in 5 cases (20.8%), and grade 2 in 1 case (4.2%). TSIR in tumor tissue was under 10% in 2 cases (9.1%); over 10% and under 20% in 4 cases (18.2 %); over 20% and under 30% in 6 cases (27.3%); over 30% and under 40% in 5 cases (22.7%); over 40% and under 50% in 3 cases (13.6%); over 50 % in 2 cases (9.1%), and not measurable in 2 cases, with the average of 29.0%. The correlation was observed between histological anti-tumor effect and TSIR in tumor tissue (p < 0.05). These results suggest the possibility that the anti-tumor effect can be estimated at the in vivo level from measurement of TSIR in tumor tissue.

Adult↗

[Treatment of solid tumor by a small amount of direct current].

Solid tumor treatment was given in our animal laboratory to determine the mechanism of tumor disappearance by direct electric current, and clinical trials were done on 9 far advanced recurrent rectal cancers. Solid tumors of Yoshida sarcoma in Donryu rat were treated by 1 mA of constant direct current for 1 hour a day, for 4 days. The tumors disappeared in 13/16 within 21 days. Positive results of DNA Nick-end labeling and ladder patterns in the gel electrophoresis of DNA were observed in the regressing tumor specimen. It is considered that apoptosis is the one of the mechanisms of a disappearing tumor. As for the clinical trial concern, in 9 cases of rectal cancer, one CR and 5 PR were seen.

Aged↗

[Left thoracotomy approach for coronary reoperation].

We experienced reoperative coronary revascularization through a left thoracotomy in 12 patients between June 1992 and June 1994. All patients underwent grafting to the left coronary system except one, who underwent bypass procedure to the atrioventricular branch of the right coronary artery in addition to grafting to the left anterior descending artery, using the pedicled left internal thoracic artery, the gastroepiploic artery as a free graft, or a reversed saphenous vein graft. In one patient, revascularization was accomplished during temporary occlusion of the coronary artery without cardiopulmonary bypass. On the other hand, in 11 patients, cardiopulmonary bypass was used. Coronary bypass procedure was employed under the ventricular fibrillation with hypothermia in those but one, who underwent revascularization under the beating heart with cardiopulmonary support. All patients were hemodynamically stable in postoperative stage, and artificial ventilation time was not prolonged, with a mean time of 15.7 hours. Postoperative morbidity included reexploration for hemorrhage in one patient, convulsion in one, worsening of hemianopsia in one, ventricular arrhythmia in one, and wound complication in one, however, there were no hospital deaths. All patients underwent repeat coronary angiography, which revealed that all grafts were widely patient except one, which had inadequate flow due to diffuse narrowing. Based on these clinical results, we conclude that a left thoracotomy is a useful approach for reoperative coronary bypass procedures to reduce the surgical risk associated with a sternal reentry in properly selected patients.

Adult↗

[Detection of loss of heterozygosity by microsatellite probe and DNA content analysis].

We examined replication error (RER) and loss of heterozygosity (LOH) in the region of microsatellites in 60 cases of resected lung cancer. We used microsatellite probes for the short arm of the 2nd chromosome (D2S123, D2S136), the short arm of the 3rd chromosome (D3S1067), and the short arm of the 17th chromosome (TP53). According to stage, the frequency of LOH was 25% in stage I, 33% in stage II, 44% in stage IIIA, 11% in stage III B, and 63% in stage IV. According to histological classification, the frequency of LOH was 41% for squamous cell carcinoma, 24% for adenocarcinoma, and 100% for small cell carcinoma. According to microsatellite probe results, the frequency of LOH was 6.7% for D2S123, 5.0% for D2S136, 16.7% for D3S1067, and 18.3% for TP53. Two of the 60 cases showed RER. One case was stage I squamous cell carcinoma, and the other was stage IV adenocarcinoma. Except for stage III B,LOH in the microsatellite region increases with the stage. LOH is often detected in the order of small cell carcinoma, squamous cell carcinoma, and adenocarcinoma. According to the chromosome number, LOH is detected more often in the 3rd and 17th chromosomes than in the 2nd chromosome. In 20 cases with LOH, only two showed DNA diploidy. Compared to LOH of the microsatellite region, DNA content analysis by flow cytometry has accuracy problems.

Aneuploidy↗

[A case of subacute sensory neuropathy associated with extraovarian serous papillary adenocarcinoma of the peritoneum].

We reported a case of subacute sensory neuropathy. A 78-year-old woman was admitted to Kenwakai Hospital because of progressive numbness in her hands and feet. Four months before admission, numbness and tingling sensations appeared in her hands and feet, and subsequently she felt difficulty in skilled finger movement. On general examination, she was found to have a mass in the right lower abdomen. Neurological examination revealed marked loss of position sense and vibratory sense in the distal extremities, and mild reduction of sensation to pinprick and light touch in the distal extremities. Stretch reflexs were depressed in the upper limbs and absent in the lower limbs. Her gait was unsteady and Romberg's sign was positive. She showed no cranial nerve dysfunction, cerebellar ataxia, muscle weakness, and autonomic dysfunction. Blood examination revealed high TTT (11.3Kunkel U), high ZTT (16.4Kunkel U) titer. Tumor markers were normal except for CA125 (93 U/ml). The cerebrospinal fluid showed 48 mg/dl of protein, 10.6 mg/dl of IgG. and an almost normal cell count (5.3/mm3). Serum was tested by immunohistochemical staining. Only the cytoplasm of neurons in the dentate nucleus and brain stem was stained on a rat's brain. Sural nerve biopsy showed a severe loss of large myelinated fibers. An exploratory laparotomy revealed a peritoneal tumor, 5 cm in diameter, and it was removed. During the surgery, other than a few rice-sized nodules in the cul-de-sac, there was no evidence of tumor in bilateral ovaries. The tumor was proven to be a serous papillary adenocarcinoma with psammoma bodies resembling ovarian cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Cost benefit analysis of care of low-birth-weight infants].

A model for cost-benefit analysis of medical care of low-birth-weight infants was proposed in order to evaluate its economic efficiency using the notion of an expected value, routinely used in economics. The expected cost and benefit when a low-birth-weight infant is born were calculated and compared. Cost includes the hospital charges and the charges for long-term care of a handicapped survivor. Benefit includes the present value of lifetime earnings. Benefit/Cost Ratio was selected as a criterion to determine efficiency, with values exceeding 1 representing the case where the expected benefit exceeds the expected cost, meaning a net economic gain. Actual values were substituted in the model for cost-benefit analysis of care of very-low-birth-weight infants. Benefit/Cost Ratios corresponding to various birth weights were calculated, and the break-even point was found to be about 800 g, which was consistent with several former reports. However sensitivity analysis indicated that Benefit/Cost Ratio was affected greatly when either the discount rate or charges for long-term care of a handicapped survivor was changed. A net economic loss would be attributable to the higher incidence of sequela corresponding to very-low-birth-weight, which would suggest that to enhance economic gain investment in care for increasing the rate of intact survivals is essential. Further study is required to define adequate values, and to determine the grade of handicap as well as lifetime earnings.

Cost-Benefit Analysis↗