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Biomedical subjects

S Yasuda

Publications and source records attributed to S Yasuda.

At least 109 records · Page 6Linked to original sources
PubMed2000

Dexamethasone-induced cardiogenic shock rescued by percutaneous cardiopulmonary support (PCPS) in a patient with pheochromocytoma.

A 52-year-old man with pheochromocytoma had cardiogenic shock and was rescued using a percutaneous cardio pulmonary supporting system. After recovery, diagnostic tests including metaiodobenzylguanidine scintigraphy and computed tomography, revealed the pheochromocytoma which was confirmed by histology. It was postulated that the acute episode was induced by intra-joint dexamethasone, which increased the production of epinephrine and augmented the sensitivity of cardiomyocytes for catecholamine, thereby inducing the cardiomyopathy.

Adrenal Gland Neoplasms↗
PubMed2000

Infratentorial arteriovenous malformation associated with persistent primitive trigeminal artery--case report.

A 58-year-old male presented with a rare association of an infratentorial arteriovenous malformation (AVM) and ipsilateral persistent primitive trigeminal artery (PPTA) manifesting as sudden onset of headache and vomiting. Computed tomography revealed subarachnoid hemorrhage, and digital subtraction angiography demonstrated an infratentorial AVM mainly fed by the left superior cerebellar artery via the left PPTA. The patient refused radical treatment for the AVM, and was conservatively treated. The adjacent AVM may have been important in the preservation of the PPTA, as blood flow into the infratentorial AVM via the PPTA and the hemodynamic stress to the PPTA could have disturbed the spontaneous closure of the PPTA.

Cerebral Angiography↗
PubMed2000

[Simple evaluation of CT findings in the paranasal sinuses for chronic sinusitis].

The CT scores and scoring for improvement based on them, which we proposed previously, is a simple and highly reproducible method of evaluation of sinus units before and after an operation for chronic sinusitis. We compared this evaluation method with the results of quantitative assay and showed its advantages and disadvantages. The subjects were 258 sinuses in patients who underwent endonasal sinus surgery (ESS) in the department of otolaryngology, Kyoto Prefectural University of Medicine Hospital from April 1996 to April 1997. The subjects were evaluated according to the following 4 grades negligible shadow in the paranasal sinus CT scored 0, less than 50% shadow scored 1, more than 50% of shadow scored 2, and mostly filled with shadow scored 3. Furthermore, the preoperative and postoperative CT scores were compared and the rate of improvement was rated in the following 3 grades: score 0 for unchanged or aggravated subjects, score 1 for subjects showing improved CT score by 1 grade, and score 2 for those showing improved CT score by 2 grades or a postoperative CT score of 0. Quantitative image analysis was input into a personal computer and the ratio occupied by the shadow was calculated, as the shadow ratio. While some discrepancies were seen in parts in the comparison of the quantitative image analysis and CT scores as the former captures minute shadows, a positive correlation was obtained overall. Attention is needed to accurately evaluate small paranasal sinuses such as the frontal sinus, and small amounts of shadow, which are areas where errors may occur. A satisfactory correlation was obtained between the score for the improvement rate and the difference in the shadow ratios before and after surgery. The CT scores and the scores for the improvement rate showed no difference from the results of other evaluation methods reported in the past, and evaluation of similar precision was possible. It was thought that this simple evaluation method of CT findings in the paranasal sinuses, which we examined in the present study, was quite useful as a simple stage-classification method that could be utilized in everyday practice considering its facility, reproducibility and satisfactory precision.

Adult↗
PubMed2000

Corticotropin-releasing hormone receptors mediate consensus interferon-alpha YM643-induced depression-like behavior in mice.

Depression-like behavior induced by YM643, a consensus interferon-alpha (IFN-alpha), was evaluated with the tail-suspension test in mice and compared with depression-like behavior induced by sumiferon, a natural IFN-alpha. To investigate the mechanism of IFN-alpha-induced depression-like behavior, the effects of the tricyclic antidepressant imipramine, the cyclooxygenase inhibitor indomethacin, the opioid receptor antagonist naloxone, and the selective corticotropin-releasing hormone receptor antagonist CP-154, 526 on IFN-alpha-induced depression-like behavior were evaluated. Intravenously injected YM643 (2 x 10(8)-2 x 10(9) U/kg) and sumiferon (2 x 10(6)-2 x 10(7) I.U./kg) dose-dependently increased immobility time. Repeated s.c. injection of either YM643 (6 x 10(6)-6 x 10(8) U/kg) or sumiferon (6 x 10(4)-6 x 10(6) I.U./kg) for 7 days also dose-dependently increased immobility time. After i.c.v. injection of either YM643 (2 x 10(6) U/mouse) or sumiferon (6 x 10(4) I.U./mouse), significant prolongation of immobility time also was observed. Pretreatment with imipramine (30 mg/kg s.c.) significantly reduced the YM643- or sumiferon-induced increases in immobility time. CP-154,526 (0.3-3 mg/kg s.c.) dose-dependently reduced YM643- or sumiferon-induced increases in immobility time with ID(50) values of 0.6 mg/kg against YM643 and 1.3 mg/kg against sumiferon. However, neither indomethacin (10 mg/kg s.c.) nor naloxone (3 mg/kg s.c.) had any effect on YM643- or sumiferon-induced increases in immobility time. These results suggest that IFN-alpha centrally induces depression-like behavior in mice that can be alleviated with imipramine. The results also suggest that activation of corticotropin-releasing hormone receptors is involved in IFN-alpha-induced depression-like behavior, but the prostaglandin and opioid systems do not participate in this process.

Animals↗
PubMed2000

New multifunctional percutaneous transluminal coronary angioplasty catheter device capable of balloon inflation, local drug delivery and coronary perfusion.

A new percutaneous transluminal coronary angioplasty catheter with multiple functions of balloon inflation, local drug delivery and coronary perfusion has been devised. The device consists of an inflatable lumen, a drug delivery lumen, and a perfusion (or guide wire) lumen. A drug can be infused from the port located distal to the inflated balloon during continuous blood perfusion via the perfusion lumen. Fluorescence-labeled heparin and peroxidase administered using the device permeated into denuded vessel tissues during ongoing perfusion and remained there for over 24 hr. This prototype device indicates the potential therapeutic implications of the concepts of the device.

Angioplasty, Balloon, Coronary↗
PubMed2000

[Clinical effects of adjuvant therapy using Z-100 (Ancer 20 injection) for oral cancer--prevention of stomatitis and hematopoietic impairment].

A combination of radiotherapy and chemotherapy is a usual treatment method for malignant head and neck tumors, however chemoradiotherapy is associated with hematopoietic impairment and serious stomatitis in patients. The clinical effects and evaluation of hematopoietic activity (e.g., leukocyte count) and the degree of stomatitis under adjuvant therapy using Z-100 (Ancer 20 injection) for oral cancer were investigated for preoperative cancer therapy. In order to evaluate the clinical effects of Ancer 20 injection with regard to hematopoietic activity and the degree of stomatitis, a clinical study was performed for 18 patients with oral cancer in our department. The 18 patients, who had oral squamous cell carcinomas (5 of the tongue, 4 of the mandibular gingiva, 3 of the maxillary gingiva, 1 of the floor of the mouth, 3 of the buccal mucosa, and 2 others), were treated with this combination of adjuvant therapy with Ancer 20 injection, from March, 1991 to March, 1997. They were injected with Ancer 20 (twice a week, 40 micrograms) during the cancer treatment period. We investigated hematopoietic activity, (e.g., leukocyte and platelet counts) and the degree of stomatitis periodically, before and after the combined radiotherapy and chemotherapy treatment period. It was found that in the patients who were treated with Ancer 20 injection, the decrease in leukocyte and platelet counts was prevented and the condition of stomatitis was improved. These results suggest that Ancer 20 injection may generally improve various dysfunctions due to hematopoietic impairment by radiotherapy combined with chemotherapy, and improve immunological factors. We conclude that Ancer 20 injection is a useful adjuvant treatment for oral cancer.

Antineoplastic Agents↗
PubMed2000

[Clinical evaluation in oral lichen planus with chronic hepatitis C: the role of interferon treatment].

Hepatitis C virus (HCV) infection induces a variety of extrahepatic manifestations such as oral lichen planus (OLP). To clarify the role of HCV in the development of OLP, we investigated the occurrence of OLP in patients with chronic hepatitis C treated with interferon (IFN). Of 275 patients with chronic hepatitis C, 6 developed OLP during the IFN treatment. However, OLP developed in none of 230 patients with chronic hepatitis C who did not undergo the IFN therapy. The IFN treatment in chronic hepatitis C patients developed OLP significantly, as compared with the non-treated group (p < 0.05). 4 of 6 patients who developed OLP during the IFN treatment had a complete response with normalization of ALT levels and undetectable HCV RNA after the treatment. There were no significant correlations between the effect of the IFN treatment and outcome of OLP. Furthermore, 3 of the 6 patients developed OLP, when serum HCV RNA became negative. These results suggest that direct viral factors may not be important in the pathogenesis of OLP in patients with chronic hepatitis C. Immunological changes caused by IFN may play a role in the development of OLP associated with HCV infection.

Adolescent↗
PubMed2000

[Recurrent tongue biting due to hypnic myoclonia in infancy].

We report a 15-month-old female infant who had recurrent tongue biting due to hypnic myoclonia. She began to bite her tongue and bleed when she was 9 months old. The tongue biting was accompanied by generalized myoclonus and was seen only during drowsiness. On admission at 15 months of age, she was observed by video-EEG monitoring. There were hypnic jerks with powerful closure of the mouth and severe screaming, but no accompanying evidence of epileptic discharges. The tongue biting with hypnic myoclonia disappeared spontaneously at 22 months of age, and was considered to be an age-dependent phenomenon related to the maturation of the brain and to the development of oral functions.

Bites, Human↗
PubMed2000

[Risk factors and physical activity levels at the onset of acute myocardial infarction in young men].

OBJECTIVES: The pathogenesis and triggering factors of acute myocardial infarction in young men remain unknown. To clarify the pathogenesis of acute myocardial infarction in young Japanese men, we compared the clinical features of patients with acute myocardial infarction in 2 age groups in Japan. METHODS: There were 37 male patients aged < 40 years (Young group; mean age 36 +/- 4 years, range 23-39 years) among 2,879 patients with acute myocardial infarction admitted to the coronary care unit of the National Cardiovascular Center, Japan, from 1977 through 1996. The clinical features of this group were compared with those of 110 consecutive male patients with acute myocardial infarction aged > or = 65 years (Old group; mean age 72 +/- 6 years, range 65-96 years) admitted in 1993-1994. Demographic features, physical activity levels at or within 2 hours before the onset of acute myocardial infarction, and coronary angiographic findings were analyzed. RESULTS: Compared with the Old group, the Young group had lower incidences of hypertension (p < 0.01) and diabetes mellitus (p < 0.01), a higher incidence of smoking (p < 0.01), higher levels of total cholesterol (p < 0.05) and body mass index (p < 0.05), and a lower level of high-density lipopotein (HDL)-cholesterol (p < 0.01). Also, the Young group had a higher prevalence of 0-1 vessel disease than the Old group (72% vs 35%, p < 0.01). The physical activity level was significantly higher in the Young group than in the Old group (2.6 +/- 2.2 vs 1.8 +/- 1.1 METs, p < 0.01). Furthermore, patients with multivessel disease in the Young group had a higher incidence of hypertension, a higher level of total cholesterol and a lower level of HDL-cholesterol (all p < 0.05), whereas those with 0-1 vessel disease had a higher incidence of heavy smoking (73% vs 50%, p = 0.1) and a tendency to higher physical activity level at the onset (2.7 +/- 2.2 vs 2.4 +/- 2.3, NS). CONCLUSIONS: Young male patients with acute myocardial infarction may be characterized by 2 distinctive patterns: one associated with smoking and a higher physical activity level at the onset of acute myocardial infarction with 0-1 vessel disease and the other with hypertension and hypercholesterolemia with multivessel disease.

Adult↗
PubMed2000

Evaluation of a surgical gamma probe for detection of 18F-FDG.

Because fluorine-18 fluorodeoxyglucose (18F-FDG) is an excellent tumor-localizing radio-pharmaceutical, a hand-held radiation detection probe capable of localizing an area with high 18F-FDG uptake would make radioguided surgery possible. In this laboratory study, we investigated the capability of a widely used intraoperative gamma probe with a cadmium zinc telluride (CdZnTe) detector for detection of 18F-FDG. For sensitivity tests, an 0.1- ml 18F-FDG preparation was made to act as a point source with radioactivities of 1.0, 2.0, and 3.0micro Ci (37 kBq, 74 kBq, 111 kBq). Relative transmission across the side wall of the probe and sensitivity at each source-to-probe distance were measured. For simulation studies, 2 l of 18F-FDG solution (0.02micro Ci, 0.74 kBq/ml) served as normal background. One ml of 18F-FDG was prepared to simulate tumors with radioactivities of 0.05, 0.1, 0.2, and 0.4micro Ci (1.85 kBq, 3.7 kBq, 17.4 kBq, and 14.8 kBq). The ratios of the radioactive concentration of tumor to that of the background were 2.5, 5, 10, and 20:1, respectively. The tested gamma probe was shown to be sensitive to 18F. The high-energy annihilation radiation was detected from the side wall of the probe despite application of a supplementary collimator. The count rate decreased markedly as the source-to-probe distance increased, owing to the effects of the inverse-square law. In the simulation studies, the probe detected a considerable amount of background activity. However, the measured count rate increased with the increasing source-to-background ratio. In our setting, the probe was capable of distinguishing the 18F-FDG source from the background when the source-to-background ratio was no less than 5:1. To make a surgical application feasible, however, collimation or shielding against high background radiation is necessary.

Fluorodeoxyglucose F18↗
PubMed1999

Impact of coronary artery remodeling on misinterpretation of angiographic disease eccentricity: evidence from intravascular ultrasound.

This study was designed to examine the impact of coronary artery remodeling, enlargement or shrinkage, on the angiographic disease eccentricity. A total of 82 coronary sites from 73 patients with significant stenosis (>50%) were prospectively analyzed by both quantitative coronary angiography and intravascular ultrasound. By quantitative coronary angiography, the maximal and minimal distances from the center of the stenosis to the outline of the vessel wall were measured, and the eccentricity index was calculated by the formula [(maximal-minimal)/maximal]. By intravascular ultrasound, the maximal and minimal distances from the center of the lumen to the leading edge of the second echogenic zone were measured, and the eccentricity index was calculated by the same formula. For identifying the vessel remodeling, the total vessel area that was determined by tracing the leading edge of the second echogenic zone was measured at the stenotic sites and the adjacent proximal and distal segments. By quantitative coronary angiography, the maximal and minimal distances were 1.76+/-0.6 and 0.97+/-0.3 mm, respectively, yielding an eccentricity index of 0.42+/-0.2. The maximal and minimal distances by intravascular ultrasound were 2.77+/-0.6 mm and 1.46+/-0.4 mm, respectively, yielding an eccentricity index of 0.45+/-0.2 (NS). Although the average eccentricity index was not different between the two methods, there was substantially no correlation between the eccentricity index determined by the two methods (r = 0.38, y = 0.43x+0.22). However, this correlation was significantly improved (r = 0.55, y = 0.73x+0.12, P<0.001) when 44 stenotic segments with remodeling were excluded for comparison. These results indicate that coronary artery remodeling could be a major contributing factor to angiographic misinterpretation of disease eccentricity. We suggest that intravascular ultrasound is a powerful method that can accurately determine diseases eccentricity as well as disease severity.

Cardiac Catheterization↗
PubMed1999

Specific IgG to gelatin in children with systemic immediate- and nonimmediate-type reactions to measles, mumps and rubella vaccines.

We examined anti-gelatin IgG in sera of children who suffered from systemic adverse reactions upon immunization with gelatin-containing live virus vaccines. In the group of 30 children who had immediate-type reactions and anti-gelatin IgE, 30 (100%) had anti-gelatin IgG and 29 (96%) had anti-gelatin IgG4. In another group of 75 children who had nonimmediate-type reactions and no anti-gelatin IgE, 22 (29%) had anti-gelatin IgG and six (8%) had IgG4. The IgG positivity well correlated with the lymphocyte proliferation assay positivity. In contrast, as a negative control, all 24 children who had no allergic reaction to live virus vaccines had no anti-gelatin IgG and IgG4. The results suggest that immune-response to gelatin may play a role in the pathogenesis of systemic nonimmediate-type reactions to the live virus vaccines.

Animals↗
PubMed1999

Peritoneal recurrence of colon cancer detected by positron emission tomography: report of a case.

Increased glucose metabolism has been reported to occur in association with colorectal cancer. As positron emission tomography (PET) using [18F]fluorodeoxyglucose is able to depict hypermetabolic sites, it can therefore be used to detect colorectal cancer. A 69-year-old male patient with a recurrent solitary liver metastasis from colon cancer underwent whole-body PET which revealed high [18F]fluorodeoxyglucose uptake in the lesion. Furthermore, PET revealed peritoneal metastases that had not been detected by conventional imaging methods. Consequently, PET proved useful in helping us to avoid performing unnecessary treatment for the liver metastasis. Although it is uncertain whether early identification of recurrence can prolong survival, it may help to prevent unnecessary treatments being carried out. Thus, the application of PET in carefully selected patients could be beneficial to the management of recurrent colorectal cancer.

Aged↗
PubMed1999

Increased FDG uptake in the wall of the right atrium in people who participated in a cancer screening program with whole-body PET.

The purpose of this study was to evaluate the characteristics of patients who showed increased FDG uptake in the wall of the right atrium. We have encountered 10 patients with increased activity in the wall of the right atrium among a total of 2,367 examinees who participated in our cancer screening program with whole-body PET. The mean age of these examinees was 62.9 yr, higher than that of the total population. All suffered from cardiac disorders, especially atrial fibrillation. FDG accumulated almost exclusively in the wall of the right atrium, whereas only slight activity was seen in the wall of the left atrium. Although the average size of the right atria was significantly enlarged, left atria were more severely dilated than right ones. Therefore overload does not seem to account for the FDG accumulation in the wall of the right atrium. In conclusion, the increased activity in the wall of the right atrium was a rare finding that was made in older people who suffered from cardiac disease. Although the mechanism of induction of the high metabolic state of glucose in the wall of the right atrium remains unclear, this unusual activity would be another false positive finding in cancer screening with whole-body FDG PET.

Adult↗
PubMed1999

Uncoupling between left ventricular contractility and relaxation after direct-current counter shocks.

Left ventricular (LV) contractility and relaxation are physiologically coupled on the basis of intracellular calcium cycling. The relation has been reported to be unique. However, this may not be always true if relaxation is predominantly impaired. Direct current counter (DC) shocks develop myocardial interstitial edema, inducing diastolic heart failure. Thus, we hypothesized that LV contractility-relaxation coupling would be altered in an experimental model of diastolic dysfunction by DC shocks. The relation between Emax (LV contractility index) and the time constant of LV pressure decay (tau) was evaluated in isovolumic contraction of seven isolated, blood perfused dog hearts. There existed a hyperbolic relation between Emax and tau in control (= pre-DC) hearts. After the application of five consecutive 80 J DC shocks, Emax was unchanged (from 4.6 +/- 1.0 to 5.2 +/- 0.8 mmHg x ml(-1) x 100 g) but tau was markedly prolonged (from 36 +/- 12 to 74 +/- 38 ms, P < 0.01). Thus, DC shocks induced a strikingly upward displacement of the hyperbolic curve compared with the control. The slope of the linear relation between Emax and the reciprocal of tau (= a relaxation velocity index normalized for contractility) significantly decreased after DC shocks. We conclude that the coupling between LV contractility and relaxation is not unique, but can be altered acutely by DC shocks. A dissociation of contractility-relaxation coupling may be of help for distinguishing diastolic heart failure and exploring its pathogenesis.

Animals↗
PubMed1999

Placenta accreta/increta. Review of 10 cases and a case report.

A review of the patients seen at the Department of Obstetrics at Dokkyo University Hospital who had suffered placenta accreta/increta in the past 18 years, was performed. There were 10 such cases out of 9,716 deliveries during this period. This incidence is higher than that which has been reported in other Western countries. Forty percent of the patients in our study had placenta accreta/increta accompanied by placenta previa or low lying; 30% had had a prior cesarean section (C/S); 70% had previously experienced dilatation and curettage (D & C); 80% had previously undergone a C/S and/or D & C: and 40% had a history of miscarriage. Three of the ten patients with placenta accreta/increta required a hysterectomy; 2 patients were successfully treated with hemostatic stitches on the endometrium; and the remaining 5 mild cases were treated with removal of the placenta, either manually or with the use of forceps. There was no case of maternal death. In 2 cases, neonatal asphyxia was noted, but the neonate immediately recovered.

Adult↗
PubMed1999

Triggering of neuronal cell death by accumulation of activated SEK1 on nuclear polyglutamine aggregations in PML bodies.

BACKGROUND: A novel class of inherited human neurodegenerations is now known to be caused by expanded CAG repeats encoding polyglutamines. Polyglutamine-containing protein fragments have been shown to accumulate as aggregates in the nucleus and in the cytoplasm, and to induce cell death when expressed in cultured cells, leading to the proposal that polyglutamine aggregation is an important step in the pathogenesis. Supporting this, nuclear inclusions containing expanded polyglutamines have been identified in neurones from the brains of patients and in neurones from transgenic mouse models of this class of neural disorders. RESULTS: We analysed the consequences of polyglutamine expression in PC12 neuronal cells. Activated SEK1 accumulated with nuclear but not cytoplasmic polyglutamine aggregations, which consequently triggers cell death. Cell death induced by polyglutamine expression was inhibited by a dominant-negative SEK1 (DN-SEK1), but not by DN-SEK1 tagged with a nuclear export signal. Steady state SEK1 expression itself was enhanced two to three-fold. Nuclearly aggregated polyglutamines, which were identified in PML bodies, co-localized with not only activated SEK1 but also activated c-Jun. We also observed that nuclear inclusion-positive neurones from brains with Huntington's disease expressed SEK1. CONCLUSIONS: This study provides molecular links between the neurodegeneration observed in polyglutamine diseases, cell death signalling kinase cascades and nuclear subdomains related to cell death. We propose that the nuclear PML bodies containing polyglutamine aggregates activate the SEK1-JNK kinase cascade, resulting in the transduction of a death signal.

Animals↗