Biomedical subjects
Publications and source records attributed to K Ohta.
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Aclarubicin was evaluated in combination chemotherapy for adult acute myeloid leukemia in a randomized trial involving 58 institutions throughout Japan. Behenoyl cytosine arabinoside (BH-AC).daunorubicin, 6-mercaptopurine, and prednisolone (DMP) was compared with BH-AC.aclarubicin, 6-mercaptopurine, and prednisolone (AMP). In the 360 evaluable cases among the 433 cases enrolled, complete remission (CR) rates were 63.7% (116/182) for BH-AC.DMP and 53.9% (96/178) for BH-AC.AMP (P = 0.0587). Median survival periods and 7-year survival rates were 15.8 months and 19.3% for BH-AC.DMP and 9.5 months and 20.2% for BH-AC.AMP (P = 0.0091 according to the generalized Wilcoxon test [GW], P = 0.196 according the log-rank test [LR]). Median disease-free survival periods were 15.4 months for BH-AC.DMP and 14.1 months for BH-AC.AMP (P = 0.851 by GW, P = 0.439 by LR). Among the 346 cases of extramurally confirmed FAB subtypes, CR rates were 67.9% (19/28) with BH-AC.DMP and 31.8% (7/22) with BH-AC.AMP for subtype M3 (P = 0.011) and 63.3% (93/147) with BH-AC.DMP and 56.8% (84/148) with BH-AC.AMP (P = 0.254) for subtypes M1, M2, M4, and M5. Diarrhea, ileus, pneumonia, and renal failure were more frequent with BH-AC.AMP than with BH-AC.DMP. The results indicate, at least on the basis of the long-term outcome, that BH-AC.AMP has antileukemic effects on subtypes M1, M2, M4, and M5 that are comparable with those of BH-AC.DMP.
We investigated the effects of selective glutamate (Glu) agonists on the release of monoamine neurotransmitters and their implication in the enhanced monoamine release in cerebral ischemia. In the striatum of anesthetized Sprague-Dawley rats, in vivo microdialysis was performed and the release of excitatory amino acids (Glu and aspartate (Asp)) and monoamines (dopamine (DA), norepinephrine (NE) and 5-hydroxytryptamine (5-HT)) was measured by high-performance liquid chromatography with an electrochemical detector. (1) Forebrain ischemia by 4-vessel occlusion generated significant correlations between the Glu and Asp levels and the DA, NE and 5-HT levels (r = 0.922-0.967, P < 0.01, n = 6). (2) L-Glu and its selective agonists (N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) and kainate (KA)) evoked a simultaneous release of striatal DA, NE and 5-HT in a dose-dependent manner (P < 0.01, ANOVA, n = 8). The maximal monoamine release evoked by the Glu agonists showed different magnitudes in the order of DA >> NE > 5-HT (118-, 16- and 9-fold from the baseline levels by 62.5 mM L-Glu, respectively). Each Glu agonist exerted a different magnitude of transmitter release and the order of agonist efficacy was different among NE, 5-HT and DA release: AMPA = KA > L-Glu = NMDA for DA release, AMPA > L-Glu = NMDA = KA for NE release, and L-Glu = NMDA = KA = AMPA for 5-HT release.(ABSTRACT TRUNCATED AT 250 WORDS)
In order to explore further the presynaptic modulation of monoamine release by glutamatergic nerve fibers, we investigated the effects of selective agonists for ionotropic glutamate (GLU) receptors on striatal release of dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (5-HT). In the striatum of anesthetized Sprague-Dawley rats, in vivo microdialysis was performed to measure the release of monoamines and metabolities, and also to administer GLU agonists locally in the tissue. L-GLU and its selective agonists (N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) and kainate (KA)) evoked simultaneous release of striatal DA, NA and 5-HT in a dose-dependent manner. Pretreatment with MK-801 (5 mg/kg i.p.), a noncompetitive NMDA receptor antagonist, selectively suppressed NMDA-evoked monoamine release. The rank order of GLU agonist efficacy in releasing monoamines was different among DA, NA, and 5-HTergic terminals: AMPA = KA > NMDA for DA release, AMPA > NMDA = KA for NA release, and NMDA = AMPA = KA for 5-HT release. In conclusion, presynaptic ionotropic GLU receptors exist extensively on monoaminergic terminals including not only catecholaminergic (DA and NA) but also indoleaminergic (5-HT) terminals in the rat striatum. Their subtypes include both NMDA subtype and AMPA/KA subtype, and show a differential distribution among these three monoaminergic terminals and a differential contribution to facilitating monoamine release.
Immunogenicity and efficacy of aerosol inactivated split influenza virus vaccines, which are threefold the strength of the vaccines for parenteral use, and cold-adapted reassortant live influenza virus vaccines were evaluated. Mucosal immune responses were evaluated by quantifying specific IgA antibody of the nasal swab solution, and systemic immune responses were evaluated by determining serum haemagglutination inhibition antibody levels. Efficacy of the aerosol inactivated vaccine was evaluated by a challenge test using live vaccine virus. It was concluded that mucosally administered inactivated influenza virus vaccine stimulated systemic and mucosal immune responses more strongly than live influenza virus vaccine and manifested a much stronger booster effect than live vaccine. Mucosal administration of inactivated influenza virus vaccine was effective in preventing infection by live vaccine virus.
Recent evidence indicates that transforming growth factor-beta 1 (TGF-beta 1) plays an important role in renal fibrosis via stimulation of extracellular matrix synthesis. The present study was undertaken to investigate the role of angiotensin II type I receptor (AT1 receptor) in hypertension-induced renal injury. Twenty-two-week-old stroke-prone spontaneously hypertensive rats (SHRSP), which had established hypertension and moderate renal damage, were orally given TCV-116, a selective non-peptide AT1 receptor antagonist (0.1, 1 or 10 mg/kg/day), enalapril (10 mg/kg/day) or vehicle once a day for 10 weeks. At the end point of the treatment, we examined renal function, the gene expressions of TGF-beta 1 and extracellular matrix components in the interstitium [collagen types I (COI) and III (COIII), fibronectin (FN)] and the basement membrane (COIV and laminin), and renal microscopic morphology in rats aged 32 weeks. In vehicle-treated 32 week-old SHRSP with renal dysfunction and nephrosclerosis, renal mRNA levels for TGF-beta 1, COI, COIII, FN, COIV were all several-fold higher than in WKY. Thus, renal TGF-beta 1 gene expression was enhanced in SHRSP, which may contribute to the increased renal expressions of COI, COIII, FN, COIV in SHRSP. Treatment with TCV-116 (0.1 mg/kg/day) in SHRSP, in spite of no reduction of blood pressure, decreased renal mRNA levels for TGF-beta 1, COI, COIII, FN, COIV, being accompanied by the significant decrease in urinary protein and albumin excretion, blood urea nitrogen and plasma creatinine. Treatment with TCV-116 (10 mg/kg/day) in SHRSP decreased mRNAs for TGF-beta 1, COI, COIII, FN and COIV to almost the same levels as WKY, being associated with normalization of urinary protein and albumin excretion and the prevention of nephrosclerosis, as judged by microscopic histological observations. On the other hand, the effects of enalapril (10 mg/kg/day) on the above mentioned mRNA levels, renal function and renal morphology were weaker than those of TCV-116 (10 mg/kg/day) and were as much as TCV-116 (1 mg/kg/day). These results suggest that independently of hypotensive action, AT1 receptor antagonist has a potent renal protective effect by inhibiting the gene expression of renal TGF-beta 1 and extracellular matrix components.
RATIONALE AND OBJECTIVES: Although many optical approaches have been investigated to diagnose breast cancers, optical parameters have never been standardized in phantom experiments; thus, the detectabilities in the various approaches could not be compared. The authors measured optical properties of the breast quantitatively using time-resolved reflectance spectroscopy to optimize the optical condition of the phantom. METHODS: A time-correlated single-photon counting method was used to obtain time-response curves of a phantom and human breasts. The optical parameters were analyzed by fitting the curves to the diffusion equation. RESULTS: The parameters could be quantified within approximately 10% error in the finite breast phantom. In vivo preliminary results showed significant individual differences. CONCLUSIONS: The authors were able to measure the optical parameters quantitatively using time-resolved spectroscopy. This optical information will contribute to the investigation of photon migration in the breast.
To evaluate the contribution of human lung mast cells (HLMC) to allergic inflammation, we investigated whether or not cytokines, including stem-cell factor (SCF), monocyte chemotactic and activating factor (MCAF), and RANTES, activate HLMC. SCF induced histamine release from dispersed HLMC in a dose-dependent fashion (P < 0.01). The release was 7.8 +/- 1.0% at 500 ng/ml SCF (n = 9). This response was also observed in chopped lung tissue. HLMC from which surface IgE molecules had been removed by treatment with lactic acid responded to SCF, while these cells lost their response to anti-IgE. The process was relatively rapid and reached a maximum in 5 min. This response required extracellular calcium, and it was observed at 37 degrees C, but not at 4 degrees C or 20 degrees. A brief preincubation (10 min) with lower concentrations of SCF, which were ineffective in releasing histamine, enhanced anti-IgE-induced histamine release (P < 0.05), while its enhancing effect was lost by the longer preincubation (30 min). SCF did not prime basophils to enhance stimulated-histamine release. Interleukin (IL)-1 alpha, IL-1 beta, IL-3, IL-4, IL-5, granulocyte/macrophage-colony stimulating factor (GM-CSF), MCAF, and RANTES neither induced histamine release nor enhanced the release stimulated by anti-IgE after a 10- or 30-min preincubation. The combination of IL-3 and IL-4 showed no effect on histamine release from HLMC. Leukotriene (LT)C4/D4/E4 production by SCF was negligible, as compared with anti-IgE-induced LT production.(ABSTRACT TRUNCATED AT 250 WORDS)
Glucocorticoids have been shown to inhibit the local accumulation of basophils during the allergen-induced late-phase reaction (LPR). Since migration is an essential step in the recruitment of basophils from the circulation, we examined whether the widely used glucocorticoid, dexamethasone (DEX), directly acts on basophils to inhibit the migration caused by C5a, interleukin (IL)-3, and IL-8. When purified basophils were preincubated with various concentrations of DEX, a dose-dependent inhibition was observed; DEX at concentrations as low as 1 nM reduced the number of migrated basophils by 30-40%; at higher concentrations, it showed a slightly stronger inhibitory effect. There was no significant difference in the effect of DEX on the migration caused by the three chemoattractants. The action of DEX took place rapidly; apparent inhibition was observed even when migration was initiated without preincubation. Although the inhibitory effect of this agent was not reversed when DEX was removed by washing, the inhibition was not mediated by the toxicity as measured by the trypan-blue exclusion test. These results indicate that the in vivo blocking effect of glucocorticoids on basophil accumulation during LPR is mediated in part by direct action to inhibit the migration of basophils.
Immunohistochemical studies were performed to clarify the significance of the expression or overexpression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v-erb B, ras p21 in 23 cases each of tubular adenoma and adenocarcinoma. The expression of EGF, EGFR, p53, v-erb B, and ras p21 in paraffin-embedded tissues, from 46 patients with colorectal tumors (adenoma: 23 cases; 14 mild dysplasia, six moderate dysplasia, three severe dysplasia, adenocarcinoma: 23 cases; 17 well differentiated, two moderately differentiated, three poorly differentiated, one mucinous carcinoma was analyzed immunohistochemically using anti-EGF, EGFR, p53, v-erb B and ras p21 antibodies. The EGF and ras p21 tended to express more strongly in carcinoma cases than in the adenoma cases, and in severe and moderate dysplasia than in mild dysplasia (EGF: stained positive in five adenomas [21.74%] and 17 adenocarcinomas [73.91%]; ras p21: stained positive in six adenomas [26.09%] and 14 adenocarcinomas [60.87%]. The EGFR stained positive in two adenomas (8.70%) and two adenocarcinomas (8.70%). The p53 and v-erb B showed positive staining only in the carcinoma cases (p53: stained positive in four cases [17.39%]; v-erb B: stained positive in eight cases [34.78%]). This study suggests that these factors seem to have some role in the progression of colon neoplasms. It suggests that genetic alteration is not always equal to the overexpression of protein products, but that it reflects them well, and that the staining makes some contribution to differential diagnosis in colorectal neoplasms.
Fibronectin plays an important role in various vascular diseases. A subpressor (200 ng kg-1 min-1) or pressor (1000 ng kg-1 min-1) dose of angiotensin II was continuously infused into rats by osmotic minipump for various times, to investigate the effects on aortic fibronectin gene expression. In rats infused with a subpressor dose of angiotensin II in which blood pressure was normal for 3 days, aortic fibronectin mRNA levels started to increase by 1.4 fold at 12 h and reached the maximal levels (increased by 3.1 fold) at 3 days. Treatment with TCV-116 (3 mg kg-1 day-1), a non-peptide selective AT1 receptor antagonist, completely inhibited the angiotensin II-induced increase in aortic fibronectin mRNA, while hydralazine (10 mg kg-1 day-1) did not block this effect. Similar results were also obtained for a pressor dose of angiotensin II. Thus, angiotensin II directly stimulates aortic fibronectin gene expression in vivo, which is mediated by the AT1 receptor but not by blood pressure.
The association between Campylobacter jejuni infection and Guillain-Barré Syndrome (GBS) was investigated serologically in 52 GBS patients. The specific antibody titers of immunoglobulin G class to C. jejuni were measured in the patient' sera using an enzyme-linked immunosorbent assay with acid-extracted antigen. The analysis showed that 31 (59.6%) of the 52 patients had evidences of recent C. jejuni infections in contrast to 16 (8.9%) of 180 healthy persons. The seropositive patients were analyzed with respect to the nature of their anticedent events. C. jejuni antibodies were found in 22 (75.9%) of the 29 patients with diarrhea, one patient with esophagus cancer, 4 (30.8%) of the 13 patients with upper respiratory infections, and 4 (50.0%) of the 8 patients without any symptoms, respectively. These findings support that there may be a close relationship between C. jejuni infection and the GBS with preceding diarrhea.
To investigate the role of angiotensin II (Ang II) in hypertension-induced tissue injury, we gave TCV-116 (1 mg/kg per day PO), a nonpeptide Ang II type I receptor antagonist, or enalapril (10 mg/kg per day PO) to deoxycorticosterone acetate (DOCA)-salt hypertensive rats for 3 weeks and examined the effects on tissue mRNA levels for transforming growth factor-beta 1 (TGF-beta 1) and extracellular matrix components. Tissue mRNA levels were measured by Northern blot analysis. Renal mRNA levels for TGF-beta 1; types I, III, and IV collagen; and fibronectin in DOCA-salt hypertensive rats were increased by severalfold (P < .01) compared with sham-operated rats. In the aorta of DOCA-salt hypertensive rats, TGF-beta 1 and fibronectin mRNA levels were increased, but types I, III, and IV collagen mRNAs did not increase. In the heart, increased mRNA was found only for fibronectin. Thus, these gene expressions are regulated in a tissue-specific manner. TCV-116 or enalapril did not lower blood pressure in DOCA-salt hypertensive rats. However, the increase in renal mRNAs for TGF-beta 1 and extracellular matrix components in DOCA-salt hypertensive rats was significantly inhibited by treatment with TCV-116 or enalapril, which was associated with a significant decrease in urinary protein and albumin excretions and histological improvement of renal lesions. In contrast, in the aorta and heart these gene expressions were not affected by TCV-116 or enalapril. Thus, local Ang II may contribute to renal injury of DOCA-salt hypertension by stimulating the gene expression of TGF-beta 1 and extracellular matrix components.
1) Forty-three chronic schizophrenics with diffuse delta activity (DDA) in their rest-awake EEGs were compared with 23 chronic schizophrenics with normal EEGs. 2) The DDA group was divided into three sub-groups according to the temporal persistence of DDA: brief, intermittent, and prolonged. The intermittent DDA is analogous to intermittent rhythmic delta activity (IRDA). 3) The disorganized type of schizophrenia was frequent in the DDA group and the residual type was frequent in the normal EEG group. 4) The doses of neuroleptics, as well as those of phenothiazines and butyrophenones, were higher in the DDA than in the normal group. 5) The frequency of co-administration of carbamazepine was higher in the DDA than in the normal group, and the rate increased with the degree of abnormality. 6) In a 1 year follow-up of the DDA group, reducing doses of neuroleptics resulted in a tendency for DDA to disappear, and reducing the doses of adjunctive carbamazepine caused DDA to disappear. 7) There was no correlation between DDA and the psychiatric symptoms, intelligence level, or CT findings.
In the present studies, the long term effects of IFN alpha on thyroid function and thyroid autoantibodies were evaluated in 42 patients with chronic viral hepatitis type C treated with IFN alpha for at least 4 months. Before IFN treatment, 41 patients tested were all euthyroid. Five (12%) out of 24 patients tested had positive tests for thyroid autoantibodies. MCHA/TPOAb was detected in all 5 and TGHA/TGAb in 3 out of these 5 patients. Six to 10 x 10(6) units (U) of recombinant or natural IFN alpha were given intramuscularly daily for the first 2 to 4 weeks, followed by 3 to 10 x 10(6) U thrice weekly for the subsequent 14 to 22 weeks. Thyroid dysfunction and/or rises in titers of thyroid autoantibodies were observed in 6 patients during IFN alpha treatment; clinically overt thyroid dysfunctions, destructive thyroiditis and thyrotoxicosis of unidentified etiology, developed in 2 patients 4 to 5 months after start of IFN treatment, subclinical hypothyroidism with a slight increase in serum TSH concentrations but no serum thyroid hormone alternations was observed in 2 patients, and increases in titers of thyroid autoantibodies without thyroid dysfunction were found in 2 patients. Thus, IFN alpha exacerbated thyroid autoimmunity exclusively in all patients with positive tests for thyroid autoantibodies prior to treatment, but did not induce thyroid autoimmunity in thyroid autoantibody-negative patients. These data suggest that the prolonged IFN alpha therapy can lead to exacerbation of thyroid autoimmunity in susceptible (thyroid autoantibody-positive) patients.
We have cloned a cDNA whose mRNA levels are increased in malignantly transformed rat thyroid FRTL cells (FRTL-Tc cells). We constructed a cDNA library from FRTL-Tc cells in lambda gt10 and screened the cDNAs by differential plaque filter hybridization. Twenty-five thousand clones were screened and one cDNA (C140) was selected which corresponded to a mRNA whose expression was 5.8 times higher in FRTL-Tc cells than in FRTL cells. A 0.8 kb specific C140 mRNA was detected by Northern blot analysis of FRTL-Tc and FRTL mRNAs. The C140 cDNA was sequenced and found to encode a protein of 227 amino acids. We have found that C140 mRNA is conserved in human thyroid cells, but it is encoded by a smaller 0.7 kb transcript. C140 mRNA was highly expressed in neoplastic thyroid tissues and weakly in normal thyroid tissues in the same patients. Additionally, we found that C140 mRNA was also increased in the thyroid tissue of a patient with Graves' disease. These results suggest that C140 expression might be higher in rapidly growing thyroid cells than in normal cells, and might provide a new aspect for the study of thyroid tumours.
Magnetic resonance imaging (MRI) revealed a small midpontine tegmentum infarction in a patient with Fisher's one-and-a-half syndrome. The lesion was extremely restricted to the unilateral paramedian area of the midpontine tegmentum involving both the paramedian pontine reticular formation and medial longitudinal fasciculus. The typical form of this syndrome, that is, a combination of lateral gaze palsy and unilateral internuclear ophthalmoplegia, can be caused by a midpontine lesion.
There is increasing evidence that airway epithelial cells play an active role in allergic inflammation, including bronchial asthma. We showed that human airway epithelial cells in culture release GM-CSF, G-CSF, M-CSF, IL-6, and IL-8, using a serum-free culture system. These cytokines are known to modulate the bioactivities of inflammatory cells that accumulate at the site of inflammation. Among them, GM-CSF, IL-8, or both may be important because they influence the bioactivities of eosinophils, which are characteristic of allergic inflammation. Here we report on the effects of air pollutants such as suspended particulate matter and diesel exhaust particulates on release of cytokines from airway epithelial cells. All air pollutants we tested stimulated epithelial cells to release GM-CSF. These results suggest that one cause of the recent increase in the prevalence of allergic disorders is direct stimulation of airway epithelial cells by air-pollutants. Furthermore, anti-inflammatory agents such as steroids and anti-allergic drugs were found to suppress the release of GM-CSF from airway epithelial cells in vitro.