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Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 145 records · Page 8Linked to original sources
PubMed2000

Non-contrast-enhanced MR angiography using 3D ECG-synchronized half-Fourier fast spin echo.

A non-contrast-enhanced three-dimensional (3D) magnetic resonance angiography (MRA) technique, which acquires images in a reasonably short scanning time and requires no contrast agent, is developed. An electrocardiographically (ECG) synchronized 3D half-Fourier fast spin-echo (FSE) technique with an appropriate ECG delay time for every slice encoding in 3D terms was used to examine the thoracic and iliac regions in 16 healthy volunteers at both 0.5 and 1.5 T. Prior to each 3D fresh blood imaging (FBI) experiment, an ECG preparation (ECG-prep) scan was acquired, and an appropriate ECG triggering time was selected for 3D FBI acquisition to optimize visualization of the vessel of interest. In the thoracic and abdominal regions, good-quality 3D MRA images were obtained. Furthermore, the weighted subtraction of two images in different phases provides contrast enhancement between arteries and veins.

Adult↗
PubMed2000

Changes of cytokines during the course of graft-versus-host disease following bone marrow transplantation: a case report.

Allogeneic bone marrow transplantation was performed in a 24-year-old woman with acute myelogenous leukemia in the first remission (FAB classification: M4). Graft-versus-host disease occurred from around day 150 after bone marrow transplantation. The levels of tumour necrosis factor-alpha, interleukin 12, and intercellular adhesion molecule-1 were elevated in the early stage of graft-versus-host disease, followed by elevation of interleukin 10 and interleukin 8. Her symptoms subsequently improved and all of these parameters became normal. The levels of thrombomodulin and plasminogen activator inhibitor type 1 showed changes that were in parallel with the clinical course. Interleukin 1beta, interleukin 6, interleukin 2, and interferon-gamma showed no changes throughout the course of her graft-versus-host disease. These findings suggested the possibility that release of inflammatory molecules occurred at the onset of graft-versus-host disease and caused vascular endothelial damage, which led to the exacerbation of her disease.

Adult↗
PubMed2000

Pulmonary mucosa-associated lymphoid tissue lymphoma 8 years after resection of the same type of lymphoma of the liver.

A 64-year-old woman presented with hepatic and pulmonary tumors of mucosa-associated lymphoid tissue lymphoma occurring 8 years apart. The present case carries the possibility of pulmonary metastasis of hepatic lymphoma or double primary lymphoma. Mucosa-associated lymphoid tissue lymphomas tend to develop in the extranodal primary organ, rarely developing systemically among extranodal organs as in our case. Our experience is useful in understanding the progress and outcome of mucosa-associated lymphoid tissue lymphoma.

Female↗
PubMed2000

Early detection of relapse and evaluation of treatment for mixed chimerism using fluorescence in situ hybridization following allogeneic hematopoietic cell transplant for hematological malignancies.

In order to detect chimerism, fluorescence in situ hybridization (FISH) and cytogenetic analyses were performed on bone marrow cells from 47 patients with hematological malignancies following allogeneic hematopoietic cell transplant (HCT). The dual-color XY, major Bcr-Abl (M-Bcr-Abl), and specific alpha-satellite probes were used for sex-mismatched HCT, chronic myeloid leukemia (CML), and myelodysplastic syndrome (MDS) cases with karyotypic abnormalities before HCT, respectively. Donor cells were found using FISH analysis in all 32 cases examined within 2 months following HCT, confirming engraftment. In six cases, however, cytogenetic analysis failed to detect donor cells due to lack of metaphases. Relapse occurred in four of the six cases in which mixed chimerism was detected using FISH analysis after 6 months of HCT. In contrast, after 12 months of HCT, no relapse was found in 24 patients without host cells. For two patients with mixed chimerism, gradual reduction of immunosuppressants or donor lymphocyte infusion resulted in the disappearance of host cells as analyzed using FISH analysis. In three extramedullary relapse cases, however, cytogenetic relapse preceded morphological and FISH relapse. These findings suggest that FISH analysis is more useful for detecting residual host cells after HCT, and the combination of FISH and cytogenetic analyses provide a more detailed evaluation for HCT patients. The results also indicate that monitoring of mixed chimerism using FISH analysis after 6 months of HCT is important for allowing the early detection of hematological relapse.

Female↗
PubMed2000

Nasal NK/T cell lymphoma presenting as transverse myelopathy.

A case of nasal NK/T cell lymphoma with central nervous system (CNS) involvement is reported. A 56-year-old man presented with eyelid edema and transverse myelopathy. Cerebrospinal fluid examination revealed atypical lymphoid cells with azurophilic granules, which were positive for CD2, CD8, and CD56, and negative for CD3 and CD5 by flow cytometry. Because a tumor mass was found involving the ethmoid and maxillary sinuses, CNS involvement was considered to have resulted from local invasion by the nasal lymphoma. In spite of intensive chemotherapy including intrathecal infusion, the patient died 6 months after the initial diagnosis. Autopsy revealed that lymphoma cells were positive for cytotoxic molecules, granzyme B and TIA-1, and EB virus-encoded RNA-1 (EBER-1), and they showed no rearrangement of TCR-beta, -gamma, or -delta genes, suggesting an NK-cell origin of the lymphoma cells. They showed an angiocentric and angiodestructive pattern in the subarachnoid space, focally extending to the cerebral cortex and cranial and spinal nerve roots. Marked demyelination was found in the lateral and posterior funiculi of the spinal cord. Thus, the pathogenesis of this spinal demyelination might be attributed to ischemia secondary to angiocentric and angiodestructive infiltration by lymphoma cells.

Diagnosis, Differential↗
PubMed2000

Biological features and preoperative evaluation of mediastinal nodal status in non-small cell lung cancer.

BACKGROUND: To examine whether biological features of primary tumor can help preoperative evaluation of mediastinal nodal status in non-small cell lung cancer. METHODS: A total of 450 patients who underwent tumor resection and mediastinal dissection were reviewed. p53 status and proliferative fraction (PI) were evaluated immunohistochemically. RESULTS: The accuracy of preoperative evaluation of mediastinal nodal status with computed tomography (CT) was 72.2%; mediastinal nodal metastases had not been revealed until operation in 59 patients (13.1%) (false-negative), and no metastasis was revealed in 66 patients (14.7%) although mediastinal nodal enlargement had been demonstrated by CT (false-positive). The number of false-negative patients was significantly larger when p53 aberrant expression was positive or when PI was higher. Combined with p53 status and PI, there were 27 false-negatives (24.1%) among patients with aberrant p53 expression and higher PI, whereas only two false-negatives (1.5%) among those with negative p53 expression and lower PI. CONCLUSIONS: Mediastinoscopy may be recommended for tumor showing aberrant p53 expression and higher PI, even when CT demonstrates no mediastinal nodal enlargement.

Aged↗
PubMed2000

Significance of cyclic adenosine monophosphate and nitroglycerin in ET-Kyoto solution for lung preservation.

BACKGROUND: We previously demonstrated that the supplement of both dibutyryl cyclic adenosine monophosphate (db-cAMP) and nitroglycerin to the conventional ET-Kyoto solution improved lung preservation significantly. However, the significance of each component in lung preservation remained unclear. We examined the efficacy of the two components on lung preservation in the current study. METHODS: Rat lung grafts (eight per group) were studied in an isolated lung perfusion model. Group 1 grafts were flushed and preserved with ET-Kyoto solution containing 2 mmol/L of db-cAMP. Group 2 grafts were flushed and preserved with ET-Kyoto solution containing 100 mg/L of nitroglycerin. In group 3, the grafts were flushed and preserved with ET-Kyoto solution containing neither db-cAMP nor nitroglycerin as control group. After 4-hour cold storage, the lung grafts were reperfused for 50 minutes. RESULTS: The lung grafts in groups 1 and 2 showed significantly better lung function after reperfusion than those in group 3 with regard to arterial oxygen tension, shunt fraction, peak inspiratory airway pressure, mean pulmonary arterial pressure, and pulmonary vascular resistance. The supplementation of db-cAMP improved especially the pulmonary arterial pressure and pulmonary vascular resistance, while the supplementation of nitroglycerin improved especially the oxygenation and airway pressure of the grafts. CONCLUSIONS: Both of db-cAMP and nitroglycerin had beneficial effects on lung preservation and are essential to the ET-Kyoto solution. There was a difference between the two components in the effects on preserved lungs.

Animals↗
PubMed2000

Bile acid sulfonate and 7-alkylated bile acid analogs: effect on intestinal absorption of taurocholate and cholesterol 7alpha-hydroxylase activity in cultured rat hepatocytes.

The effects of sulfonate analogs of cholic (C), chenodeoxycholic (CDC), and ursodeoxycholic acid (UDC) and three 7-alkylated CDCs--7-methyl-, 7-ethyl-, and 7-propyl-CDCs--on taurocholate absorption from rat terminal ileum in situ and on cholesterol 7alpha-hydroxylase activity in primary culture of the rat liver were investigated. The sulfonate analogs of two dihydroxy bile acids CDC and UDC, but not C, significantly decreased the absorption of taurocholate. Taurine conjugates of 7-alkylated CDC slightly decreased the taurocholate absorption, and tauro-7-propyl-CDC significantly suppressed the absorption. Although the sulfonate analogs of C and CDC reduced cholesterol 7alpha-hydroxylase activity by 40% and 60% compared to control, UDC-sulfonate analog did not affect enzymatic activity. These results were consistent with those of the lead compounds, C, CDC, and UDC. The introduction of methyl group at C-7 position of CDC attenuated the reduction in cholesterol 7alpha-hydroxylase activity by CDC. However, elongation of the alkyl group resulted in an inhibitory effect. The present study revealed the following: 1) bile acid sulfonates act on cholesterol and bile acid metabolism in a similar manner as taurine conjugated bile acids; and 2) the biologic properties of CDC could be altered by the introduction of alkyl group at C-7 position.

Animals↗
PubMed2000

Human anti-murine antibodies interfere with CPR assays performed with commercial kits.

Quantitation of C-peptide is important for the assessment of insulin secretion, in particular in patients receiving insulin therapy. Since the CPR levels become much higher than the concentration of C-peptide for several reasons, such as the high concentration of proinsulin, CPR values sometimes need to be assessed carefully. We have had two diabetic patients whose CPR values were abnormally high when determined with a Daiichi C-peptide kit III (method 1). CPR values determined by other methods were from two to ten times lower, indicating considerable interference when method 1 was used. Since method 1 uses mouse monoclonal antibodies (mmab) for detection antibodies, we suspected that human anti-murine antibodies (HAMA) were responsible for the interference. HAMA were detected in serum from both patients (45 and 460 ng/ml in case 1 and case 2 (at peak), respectively). Removal of HAMA from serum eliminated the interference. Modification of method 1 to exclude mmab from the assay system removed all interference. HAMA were, therefore, considered to be the cause of the interference. In case 2, the peak concentration of HAMA was recorded 16 months earlier than the maximum of interference. Further analysis revealed that HAMA with high affinities were responsible for the interference.

Aged↗
PubMed2000

Complete skipping of exon 66 due to novel mutations of the dystrophin gene was identified in two Japanese families of Duchenne muscular dystrophy with severe mental retardation.

Severe mental retardation is a rare complication of Duchenne muscular dystrophy (DMD). Here we report that two DMD cases showing severe mental retardation exhibit the same exon skipping event induced by different intron mutations. In the two Japanese DMD patients studied, the complete sequence of exon 66 of the dystrophin gene was found to be absent from the dystrophin mRNA, creating a premature stop codon in exon 67. Novel point mutations at the consensus sequence of the splice donor site of intron 66 (T9857(+2) to C in one case and G9857(+5) to T in the other case) were found to be the cause of complete exon skipping. Remarkably, severe mental retardation cosegregated with an exon 66-skipping event in their families. Furthermore, pachygyria was disclosed by magnetic resonance imaging (MRI) examination of the brain of one case. Our results suggested that exon 66 skipping should be examined in DMD cases with a severe form of mental retardation.

Adult↗
PubMed2000

Endothelin-1 as a protective factor against beta-adrenergic agonist-induced apoptosis in cardiac myocytes.

OBJECTIVES: The purpose of this study was to investigate the regulation of beta-adrenergic agonist-induced apoptosis by endothelin-1 (ET-1) in cardiac myocytes. BACKGROUND: Numerous hormonal factors including norepinephrine and ET-1 are activated in patients with heart failure. These factors may be involved in the positive and negative regulation of myocardial cell apoptosis observed in failing hearts. Recently, it has been shown that norepinephrine can induce myocardial cell apoptosis via a beta-adrenergic receptor-dependent pathway. METHODS: Primary cardiac myocytes were prepared from neonatal rats. These cells were stimulated with the beta-adrenergic agonist isoproterenol (ISO) in the presence or absence of ET-1. RESULTS: The administration of 10(-7) mol/liter of ET-1 completely blocked Iso-induced apoptosis. An endothelin type A receptor antagonist, FR139317, negated the inhibitory effect of ET-1 on apoptosis, while the endothelin type B receptor antagonist BQ788 did not show such a negation. Endothelin-1 also inhibited apoptosis induced by a membrane-permeable cAMP analogue (8-Br-cAMP), which bypassed Gi. The effect of ET-1 was neutralized by an MEK-1-specific inhibitor (PD098059), a phosphatidylinositol 3'-kinase inhibitor (wortmannin) and its downstream pp70 S6-kinase inhibitor, rapamycin. CONCLUSIONS: These findings suggest that ET-1 represents a protective factor against myocardial cell apoptosis in heart failure and that this effect is mediated mainly through endothelin type A receptor-dependent pathways involving multiple downstream signalings in cardiac myocytes.

Adrenergic beta-Agonists↗
PubMed2000

Evaluation of tracheo-bronchial wall invasion using transbronchial ultrasonography (TBUS).

BACKGROUND: Whereas accurate evaluation of tumor invasion into the tracheo-bronchial wall is a critical factor in decision-making of therapy for intra-thoracic malignancies, it is sometimes difficult with usual thoracic imaging techniques such as computed tomography. As recent progress in technology of ultrasonography is marked, usefulness of transbronchial ultrasonography (TBUS) in evaluation of tracheo-bronchial wall invasion was assessed. METHODS: Following routine fiberoptic bronchoscopy, an ultrasound probe (20 MHz) covered with a balloon sheath was inserted through the bronchoscope. After air present between the ultrasound probe and the tracheo-bronchial wall was eliminated with filling the balloon with distilled water, TBUS imaging was taken. RESULTS: With TBUS, normal tracheo-bronchial wall was represented as a five-layer structure at the cartilagenous portion and a three-layer structure at the membranous portion. Based on this normal TBUS imaging, tumor extent was judged in 35 patients with intra-thoracic malignancies. Among 25 patients with extra-wall tumor including esophageal cancer (n=15) and metastatic lymph nodes (n=7), tracheo-bronchial wall invasion was clearly demonstrated in nine patients, and no invasion was demonstrated in the other 16 patients. Among ten patients with tumor originating from the tracheo-bronchial wall, tumor extent beyond outer border of the wall was demonstrated with TBUS in five patients. These diagnoses were examined pathologically in 15 patients who underwent the operation, and the accuracy was 93.3%. CONCLUSIONS: It is suggested TBUS can be a useful diagnostic tool in evaluation of tumor invasion to the tracheo-bronchial wall.

Adult↗
PubMed2000

Surgery for non-small cell lung cancer: postoperative survival based on the revised tumor-node-metastasis classification and its time trend.

OBJECTIVE: To clarify results of surgery for non-small cell lung cancer (NSCLC) based on the new tumor-node-metastasis (TNM) classification revised in 1997 and its time trend. METHODS: A total of 921 patients operated from 1980-1994 were retrospectively reviewed. For analysis of time trend, they were grouped into three periods by the year of operation (period (1): 1980-1984, period (2): 1985-1989, and period (3): 1990-19-94). RESULTS: Concerning patients' characteristics, recent increase in the ratio of patients whose tumor was discovered at mass screening (31% in period (1), 40% in period (2), and 50% in period (3)), and increase in the ratio of p-stage IA patient (16, 20, and 29%, respectively) were marked. Decrease in the ratio of operation-related death and the ratio of exploratory thoracotomy was significant. Concerning level of operation, decrease in the ratio of pneumonectomy, increase in the ration of sublober resection and that of tracheal or bronchoplastic procedures were significant. Postoperative survival for all patients was significantly better in period (2) or (3) than that in period (1); no significant difference was demonstrated between period (2) and (3) (5-year survival rates: 35% for period (1), 56% for period (2), and 56% for period (3)). Stratified p-stage, improvement of postoperative survival in recent years was demonstrated in p-stage IIA, IIB, IIIA, and IIIB diseases. CONCLUSIONS: Postoperative survival for all NSCLC patients has been improved with significant increase of early-stage (p-stage IA) patients. Concerning level of resection, recent increase in patients who underwent sublobar resection and bronchoplastic procedures was marked.

Adult↗
PubMed2000

Autonomic regulation after exercise evidenced by spectral analysis of heart rate variability in asthmatic children.

BACKGROUND: Bronchial asthma is associated with abnormal autonomic nervous function in childhood. Exercise is one of the most common precipitating factors of acute asthmatic crises although the exact mechanism of autonomic regulation in asthmatic children after exercise is unclear. OBJECTIVE: The aim of this study was to investigate the features of autonomic regulation after exercise in asthmatic and control children. METHODS: Pulmonary function tests and heart rate variability spectral analysis were performed in 15 asthmatic children and 7 control children (age 6 to 15 years) during and after an exercise challenge. RESULTS: The maximum % fall of forced expiratory volume in 1 second (FEV1) was significantly greater (P < .01) in asthmatic subjects (9.1 +/- 5.1%) than in normal control subjects (1.0 +/- 2.5%). The high frequency band (HF) amplitude, an index of cardiac vagal tone, 5 minutes after exercise was significantly higher (P < .05) in the asthmatic subjects (14.4 +/- 7.9 msec) than in control subjects (5.9 +/- 2.6 msec). Furthermore, the difference in the HF amplitude between the control group and the exercise-induced asthma group was significant both 5 minutes (P < .01) and 10 minutes (P < .05) after challenge. There was a significant correlation (P = .565, P = .0165) between HF amplitude 5 minutes after exercise and the magnitude of the decrease in FEV1. On the other hand, no significant difference was observed in the low frequency band amplitude between the controls and the asthmatic subjects. The ratio of low frequency to high frequency power, which is suggested to correlate with cardiac sympathetic activity, did not differ between the two groups. CONCLUSION: These findings suggest that autonomic nervous activities, particularly vagal response after exercise, in asthmatic children is different from that in control children.

Adolescent↗
PubMed2000

Association of cytomegalovirus interstitial pneumonitis with HLA-type following allogeneic bone marrow transplantation.

Certain human leukocyte antigens may increase the risk of cytomegalovirus interstitial pneumonitis, an important complication of bone marrow transplantation. The prevalence of this pneumonitis was compared between patients possessing either HLA-B51 or HLA-B52 and patients without either antigen. The role of tumor necrosis factor-alpha in cytomegalovirus interstitial pneumonitis was also studied. Among 72 patients undergoing allogeneic bone marrow transplantation at our institution during the past 5 years, HLA-B51 or -B52 was detected in 29. Among these 29 patients, 13 (45%) developed cytomegalovirus interstitial pneumonitis, a significantly higher rate (P < 0.001) than among patients without these HLA types (4/43, 9%). In the pre-conditioning and stable phases, tumor necrosis factor-alpha levels were higher in patients with HLA-B51 or HLA-B52 than in patients without (P < 0.05; t-test). Throughout the period from pre-conditioning to around day 40, except on day 0, tumor necrosis factor-alpha levels were also significantly higher (P < 0.05 to P < 0.001) in patients developing cytomegalovirus infection than in those without it. These results suggest that HLA-B51 and HLA-B52 may be risk factors for cytomegalovirus interstitial pneumonitis after bone marrow transplantation, with an increase of tumor necrosis factor-alpha also being involved.

Adolescent↗