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Y Namba

Publications and source records attributed to Y Namba.

At least 145 records · Page 8Linked to original sources
PubMed1985

Sensory and motor responses to deep brain stimulation. Correlation with anatomical structures.

Motor and sensory responses induced by trial stimulation were examined before stereotaxically implanting a permanent stimulating electrode for pain relief in 11 patients with intractable pain of central origin. The total number of points eliciting a response when stimulated was 70. The points of stimulation were determined as exactly as possible from Schaltenbrand and Bailey's Atlas. Motor responses were detected upon stimulating 21 points, the majority of which were in the posterior third of the posterior limb of the internal capsule (IC). Stimulation of these 21 points was accompanied by pain relief in only two points (10%). Warm (22) or cool sensations (three) were provoked in the most posteromedial portion of the posterior limb of the IC, nucleus reticularis pulvinaris, and area triangularis, and seven (28%) of these 25 sensations were accompanied by pain relief. A burning sensation was found upon stimulation of 12 points, with stimulation in the mesencephalic lateral tegmental field eliciting the most severe burning pain. A tingling sensation was elicited at 12 points, in a distribution similar to that of the warm sensation. Five (42%) of these 12 points provided pain relief. The best stimulating point for pain relief is not in the center of the posterior limb of the IC, directly lateral to the posterior commissure, but rather in its most posteromedial part; that is, at the nucleus reticularis pulvinaris or area triangularis.

Adult↗
PubMed1985

Immunoregulatory role in gamma interferon production by a T cell growth factor-dependent experimental malignant glioma-specific cytotoxic T lymphocyte clone.

The authors have established a murine malignant glioma-specific cytotoxic T lymphocyte clone (G-CTLL 1) by T cell growth factor (TCGF) using 203-glioma (a methylcholanthrene-induced ependymoblastoma of C57BL/6 mouse origin). The cloned cells were found to release a large amount of gamma interferon (IFN) in response to glioma-associated antigen-specific stimulation. The authors have investigated whether the IFN produced can contribute to killing the target cells. Adding anti-mouse gamma IFN antibody to the mixed clone-target cell culture inhibited IFN production by the cloned cells but the toxicity of the cells was minimally diminished. Therefore, it is suggested that the endogenous gamma IFN produced by the TCGF-dependent cloned cytotoxic T lymphocyte line does not have direct cytotoxic action on the target cells. Furthermore, IFN production as well as cytotoxicity was blocked by anti-Lyt-2 monoclonal antibody in the absence of complement. This suggests that IFN plays a role in the process of antigen recognition of target cells because the Lyt-2 molecule is involved in an antigen-specific function on the cytotoxic T lymphocyte receptor. The role of TCGF in gamma IFN production was also investigated. The spontaneous production of gamma IFN by the cloned cells paralleled the amounts of exogenous TCGF added to the cultures, but TCGF had no synergistic effect on IFN production in the presence of mitogen or tumor antigen. Accordingly, it is possible that TCGF stimulates the cloned cells to proliferate, causing IFN release.

Animals↗
PubMed1985

[beta-Endorphin and monoamine metabolite concentrations in patients with intractable pain--changes before and after deep brain or spinal dorsal column stimulation].

Baseline concentrations of beta-endorphin (beta-EP) and monoamine metabolites (MHPG: 3-methoxy-4-hydroxy-phenylglycol, HVA: homovanillic acid, 5-HIAA: 5-hydroxyindoleacetic acid) in lumbar CSF (LCSF) and ventricular CSF (VCSF) were measured in 18 patients with intractable pain; 10 with deafferented pain and 8 with peripheral pain. Control values were obtained from 37 individuals of various ages. Changes in the concentrations of these substances were determined before and after giving stimulations (2-5 V, 0.2-0.5 msec, 40-50 Hz, 20-sec duration) to 6 patients through electrodes implanted in deep brain structures (DBS; posterior limb of the internal capsule in 5 patients and rostral mesencephalic lemniscus medialis in one patient), and to 2 other patients through electrodes implanted in the spinal dorsal column (DCS). The control value of beta-EP in LCSF was 57.6 +/- 24.7 pg/ml, which was not significantly different from that of VCSF. Great variation in the individual control LCSF beta-EP concentrations was found, but it was not related to differences in age. The mean baseline LCSF beta-EP concentration was significantly higher (p less than 0.05) than the control in the patients with deaffernted pain before stimulation. One of the monoamine-metabolites, MHPG, showed higher level in the patients with peripheral pain (p less than 0.01). The LCSF beta-EP concentration was not affected by deep brain stimulation, but was increased by dorsal column stimulation. In one patient with excellent pain relief by stimulation of the posterior limb of the internal capsule, the LCSF HVA and 5-HIAA concentrations were conspicuously increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

[Prediction of coronary lesions by two-dimensional echocardiography in patients with healed myocardial infarction].

Regional left ventricular wall motion abnormalities were assessed by two-dimensional echocardiography (2-DE) in 66 patients with healed myocardial infarction (MI) and the results were compared with those of coronary angiography which was performed at nearly the same time as 2-DE. The left ventricular wall was divided into 14 segments and asynergy was assessed in each segment. To compare the severity of segmental asynergy with coronary artery lesions, relation between segments and coronary artery perfusion was assumed as follows: the anterior wall, anterior septum and apex corresponded to the anterior descending artery (LAD); the lateral and inferior walls corresponded to the left circumflex artery (LCX); and the posterior septum and inferior wall corresponded to the right coronary artery (RCA). One vessel disease: In all 24 patients with MI induced by LAD lesions, regional asynergy was identified in the anterior wall, anterior septum and apex. All patients had advanced asynergy (severe hypokinesis, akinesis or dyskinesis) except one with subendocardial infarction. Advanced asynergy was identified in the other segments including the lateral wall (one patient) and the posterior septum (11 patients), but such asynergy was not associated with that of the inferior wall. In four patients with MI induced by RCA lesions, regional asynergy appeared in localized segments of the posterior septum and inferior wall, and the asynergy was severe in all patients except one in whom collaterals were well-developed. In four patients with MI induced by LCX lesions, asynergy was observed in both the lateral and inferior walls. In only one patient, mild asynergy was identified in the apex. Multi-vessel disease: In both groups with double vessel (16 patients) and triple vessel (16 patients) disease, asynergy was recognized in the affected areas of the major coronary artery which was considered responsible for the infarction, irrespective of the severity of the coronary stenosis. Also, there was no significant correlation between the severity of coronary artery stenosis and segmental wall motion abnormalities in non-infarcted areas. No significant correlation was observed between the severity of regional wall motion abnormalities in the infarcted areas and the degree of development of collaterals. In patients with MI induced by LAD lesions, more extensive asynergy in the anterior wall and anterior septum at the basal portion was observed in the patient group with proximal stenosis than in the group with distal stenosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1984

Specific adoptive immunotherapy of malignant glioma with long-term cytotoxic T lymphocyte line expanded in T-cell growth factor. Experimental study and future prospects.

The purposes of the current study were: (1) to investigate the immunoregulatory effects of T-cell growth factor (TCGF) on the activation and differentiation of syngeneic cytotoxic T lymphocyte (CTL) populations generated against a 20-methylcholanthrene-induced ependymoblastoma, 203-glioma, in C57BL/6 mice; and (2) to determine whether the glioma-specific CTL clone (G-CTLL) could be established by TCGF, and whether the in vivo efficacy of the cloned cells could be rendered more effective in adoptive therapy. It was found that TCGF largely allows the CTL populations to proliferate and thus can activate the depressed cytotoxic activity in tumour-bearing mice. Two lines of G-CTLL were successfully obtained by the limiting dilution technique. The G-CTLL retained a TCGF-dependent proliferative growth and a marked cytotoxic activity with target specificity for over 18 months, characterized by a surface phenotype of Lyt-1-.2.3+, Lyt-2 antibody blocking of cytotoxicity and the production of immune interferon in response to mitogen and tumour antigen. In the Winn assay and the adoptive transfer assay, the therapeutic effects were detected in intracranially inoculated tumours in mice. The in vivo efficacy was dependent on the dose of G-CTLL and on the time of the intravenous administration, although the transfer was inversely ineffective in conditions of increased intracranial pressure. The mechanism responsible for the in vivo effect was probably due to the adoptive immunity and/or the tumour-specific interferon production of G-CTLL.

Animals↗
PubMed1984

Bacterial contamination of floors and other surfaces in operating rooms: a five-year survey.

Bacterial contamination of floors and other surfaces in the operating suite has been investigated by contact impression plates during the past five years. Colony counts of the floors of operating rooms, cleaned with disinfectant, were 3.3 c.f.u./10 cm2; on the floors of semi-clean and dirty areas, cleaned with detergent, colony counts were 44.8 and 71.4 c.f.u./10 cm2 respectively. The highest colony counts of 487.4 c.f.u./10 cm2 were found in the dressing rooms, the floors of which were covered with carpets, cleaned with a vacuum cleaner. Mean bacterial numbers on surfaces of various equipment in operating rooms, cleaned with disinfectant, were 2.8 c.f.u./10 cm2. Bacterial numbers on surfaces decreased markedly from 253.2 to 11.9 c.f.u./10 cm2 following the use of disinfectant. Bacterial species found from various surfaces were mainly coagulase-negative staphylococci, derived from human beings. In the light of these findings the regular use of disinfectant for cleaning of the floors and other surfaces in operating rooms is advisable.

Bacteria↗
PubMed1984

Airborne contamination in an operating suite: report of a five-year survey.

Airborne contamination in an operating suite was studied with a slit sampler, settle plates and a light-scattering particle counter. In conventional operating rooms there was a significant difference between the empty rooms and rooms in use; the mean total bacterial count by a slit sampler changed from 1.1 in empty to 42.5 c.f.u./m3 in use (39 times increase), the settle plates count changed from 1.5 to 17.4 c.f.u./m2/min (12 times increase), and the mean total particle count changed from 56.9 to 546.7/l (10 times increase) respectively. The increase was caused mainly by persons present in the room. Another difference was found between zones in the operating suite; the bacterial count in the clean area doubled in the semi-clean area and further doubled in the dirty area in slit sampler count as well as settle plates count, and particle count in the clean area increased by 14 times in the semi-clean and dirty areas. This difference resulted from the different quality of the ventilating system. Air cleanliness of operating rooms in use by persons present in the room dropped to a level between the clean and the semi-clean area in spite of the high quality of the ventilating system. Bacterial species identified were mostly coagulase negative staphylococci and micrococci. Our study indicates that reduction of airborne contamination in an operating suite is accomplished by the combination of an efficient ventilating system and the restriction of the number of persons present in the room.

Air Microbiology↗
PubMed1984

A new approach to the detection of autoantibodies against insulin receptors that inhibit the internalization of insulin into human cells.

It has been shown that the conjugate of the fragment A of diphtheria toxin to insulin is cytotoxic to cultured cells bearing insulin receptors, apparently through the endocytosis of fragment A. We examined the effect of autoantibodies against insulin receptors on the cytotoxicity of the conjugate. The conjugate was cytotoxic to a rat fibroblast cell line that was resistant to the intact toxin, and the cytotoxicity was inhibited by exogenous insulin, indicating that the fragment A underwent endocytosis through insulin receptors. Immunoglobulins from three patients with type B syndrome of insulin-resistant diabetes blocked the cytotoxicity of the conjugate to Chang's liver cells in a dose-dependent manner. When the cells were pretreated with the immunoglobulins, cytotoxicity of the conjugate was also blocked. These results suggest that autoantibodies against insulin receptors interfere with the binding of the conjugate to insulin receptors or with the endocytosis of fragment A after binding. This assay system seems useful for detecting autoantibodies against the determinants that are involved in the internalization of the ligand-receptor complex.

Animals↗
PubMed1984

Establishment of experimental malignant glioma-specific cytotoxic T lymphocyte clone by T cell growth factor.

In an attempt to facilitate the long-term proliferative growth and subsequent cloning of cytotoxic T lymphocytes (CTL's) against syngeneic murine 203-glioma (20-methylcholanthrene-induced ependymoblastoma of C57BL/6 mouse origin), sensitized T lymphocytes from tumor-bearing mice were cultured in the presence of T cell growth factor (TCGF). Of five clones established by a limiting dilution technique, two clones (G-CTLL 1 and 2) exhibited tumor-specific cytotoxicity. G-CTLL 1 cells, which possessed much higher cytotoxic activity than G-CTLL 2 cells, were further analyzed. G-CTLL 1 cells were maintained in a TCGF-dependent exponential proliferative culture for over 18 months and continued to mediate an extremely high cytotoxic activity with the target specificity (50- to 100-fold increases over the peak cytotoxic activity of sensitized T lymphocytes in tumor-bearing mice). Their phenotypes of surface antigens were Thy-1+ (weak positive), Lyt-1.-2.+3+, and asialo-GM1-, and their cytotoxicity was blocked by adding only anti-Lyt-2 monoclonal antibodies. These results indicated that the cloned cells originated from CTL's. The cloned cells were characterized by the production of immune interferon with the glioma antigen-stimulation, suggesting that the immune interferon could enhance the cytotoxic activity of the CTL clone at the site of a clone-target cell recognition event.

Animals↗
PubMed1984

Specific adoptive immunotherapy with tumor-specific cytotoxic T-lymphocyte clone for murine malignant gliomas.

The efficacy of glioma-specific cytotoxic T-lymphocyte for a syngeneic murine malignant glioma (a 20-methylcholanthrene-induced ependymoblastoma, 203-glioma) was investigated. The cytotoxic clone (G-CTLL 1), established and expanded exponentially by T-cell growth factor, has retained target specificity for more than 6 months. In adoptive therapy and Winn assay, the in vivo antitumor activity of G-CTLL 1 was demonstrated against mice inoculated intracranially with 203-glioma cells. The therapeutic effects in adoptive immunotherapy were largely dependent on dose and time of i.v. administration, although the therapy was rather ineffective in condition of increased intracranial pressure due to the tumor growth. The mechanisms responsible for the in vivo protection were probably related to the killing activity of G-CTLL 1 or the tumor-specific production of immune interferon by G-CTLL 1.

Animals↗
PubMed1984

[Effects of TCGF (T-cell growth factor) on experimental malignant glioma-specific killer T-cell].

The immunoregulatory effects of TCGF (T-cell growth factor) on the generation and growth of syngeneic murine malignant glioma (20-methylcholanthrene-induced 203-glioma)-specific killer T-cell were investigated in C57BL/6 adult mice in order to clarify the immunopotential usefulness for anti-tumor local adoptive immunotherapy against malignant brain tumor. TCGF was prepared and assayed. Briefly, 5 x 10(6) ml mouse spleen cells were cultured with 2 microgram/ml concanavalin A in RPMI-1640 medium supplemented with 2% fetal calf serum for 24 hours. Culture supernatants were concentrated by ammonium sulphate precipitation (55 to 80% saturation) and purified by gel filtration (Sephadex G-100, a molecular weight from 30 to 36,000 daltons) and ion exchange chromatography (DEAE-cellulose, elution with 0.15 M in NaCl at ph 7.4). The purified TCGF had no IFN activity. Assays for TCGF was performed for quantitative analysis using 203-glioma-specific killer T cell clone (G-CTLL), which was obtained by limiting dilution method (0.3 cells/well in 96 well microtiter plate) and maintained for over 6 months in the presence of TCGF. Titer (U/ml) of TCGF was defined as the quantity of TCGF required to obtain one-half of the maximal stimulation of G-CTLL proliferation assay. It was confirmed that the specific killer T-cell against 203-glioma was generated in mice after intracranial as well as subcutaneous inoculation of the tumor cells. The killer T-cell activity of spleen cells, however, began to be severely impaired 2 weeks after intracranial inoculation concurrently with the increased intracranial pressure due to developing the tumor growth. Sensitized lymphocytes obtained from intracranial and subcutaneous tumor-bearing mice were assessed for CTL (cytotoxic T-lymphocyte) activity in MLTC (mixed lymphocyte-tumor cell culture) for 18 hours by microcytotoxicity assay. The specific cytotoxicity against 203-glioma cells was enhanced when sensitized lymphocytes from intracranial and subcutaneous tumor-bearing mice were pre-cultured with optimal TCGF (20 U/ml) for over 5 days. After the treatment of sensitized lymphocytes with anti-Thy-1 monoclonal antibody and complement, however, the specific cytotoxicity of sensitized lymphocytes was eliminated almost completely. Therefore, it was thought that TCGF possesses immunoregulatory effects of enhancement of killer T-cell activity. On the contrary, TCGF had no influence on normal T lymphocytes and the growth of 203-glioma cells in vitro.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1983

[Suppressor mechanism in tumor immunology: characteristics of suppressor T-cells in glioma-bearing mice].

Suppressor T cells in syngeneic tumor-bearing mice that inhibited in vitro generation of tumor antigen-specific cytotoxic T lymphocytes were characterized with respect to the kinetics, the nature and the target specificity, using murine malignant glioma (a methylcholanthrene-induced malignant ependymoblastoma, 203-glioma). Suppressor cell activity was assessed by the inhibition of tumor cell killing activity of cytotoxic T lymphocytes, which were prepared from splenic T enriched lymphocytes of mice immunized with 1 X 10(6) mitomycin C (50 micrograms/ml, 45 minutes)-treated 203-glioma cells twice at an interval of 7 days. It was confirmed that suppressor T cells were generated in 203-glioma-bearing mice, and they were tumor antigen-specific as evidenced by the fact that sensitized splenic T lymphocytes from mice bearing other syngeneic EL4 thymoma or allogeneic P 815 mastocytoma or YAC-1 T cell lymphoma did not exhibit the inhibition of the cytotoxic T lymphocyte activity against 203-glioma cells. Significant suppressor cell activity was detected in spleen cells 1 to 5 days after the subcutaneous inoculation of 203-glioma cells with the peak activity on day 3 and it disappeared as early as on day 7, suggesting strongly that the turn-over of suppressor T cells is very quick. Surface markers of suppressor T cells in 203-glioma-bearing mice were checked on day 3 with the results that the suppressor cell activity was eliminated by the treatment with anti-Lyt-2 monoclonal antibody and complement, indicating that the phenotype of suppressor T cells is Lyt-1-.2.3+.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗