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K Taniguchi

Publications and source records attributed to K Taniguchi.

At least 847 records · Page 47Linked to original sources
PubMed1984

Threshold response phase to sinusoidal stimulation of frog cutaneous mechanoreceptor afferent units.

While applying sinusoidal indentations of various frequencies and amplitudes to the receptive field of cutaneous mechanoreceptor afferent units in frogs, we measured latencies of spikes after the time point when sinusoidal stimulation crossed the neutral position from withdrawal to indentation phase. Frog type I (Ft I) and frog type II (Ft II) slowly adapting (SA) units produced spikes only at the indentation phase, and the threshold response phase (TRP), i.e.. the phase of the first spike was for ca. 45 degrees at a small amplitude of stimulation. At low frequencies of sinusoidal stimulations, the TRP of Ft II units advanced gradually with an increase in amplitude, conforming to the theoretical expectation as displacement-detectors. But the TRP of Ft I units did not show such an advance with an increase in stimulus amplitude. Rapidly adapting (RA) type I and type II units mostly produced phase-locked discharged at two different phases; the former discharged at ca. 0 degrees and 180 degrees (phase of the highest velocity) and the latter at ca. -90 degrees and 90 degrees (phase of the highest acceleration) at the smallest amplitude used. At a large amplitude, RA type II units showed advance in discharge phase like a theoretical acceleration-detector, but performance of RA type I units dit not fit that of the theoretical velocity-detectors. Both types of SA units showed frequency-phase relations which roughly agreed with the performance of the theoretical displacement-detectors in the range below 5 Hz, but RA units of either type did not follow the expectation as the theoretical velocity-detector or acceleration-detector.

Animals↗
PubMed1984

Discharge patterns of the slowly adapting mechanoreceptor afferent units innervating the non-warty skin of the frog.

Discharge patterns of slowly adapting (SA) mechanoreceptor afferent units innervating the non-warty skin of frogs, were analyzed statistically. Because SA units in the frog did not always produce sustained discharges for a long period, analysis was carried out on ensembles of interspike intervals (ISIs) obtained in two ways: (1) a series of successive ISIs obtained in the quasi-stationary state of maintained discharges and (2) an ensemble of ISIs (X(1),X(2),..., X(50)), obtained on repeated trials of stimulation at about 1,000 msec following the onset of stimulation. In some units these two types of ensembles of ISIs were collected. Statistical analysis of a series of successive ISIs in the quasi-stationary state disclosed two kinds of discharge patterns, irregular and regular, corresponding to those of the SA cutaneous units of mammals and reptiles. We named these two types of units Frog type I and Frog type II (Ft I and Ft II) units, respectively. In addition, the quantitative study of an ensemble of ISIs in the non-stationary state revealed that Ft II units discharged regularly in response to an optimum range of indentation but irregularly to indentation outside this range, although Ft I units produced irregular discharges irrespective of the magnitude of indentation applied.

Adaptation, Physiological↗
PubMed1984

[Clinico-pathological study on the appropriate range of pancreatic resection to obtain operative curability of pancreatic head cancer].

We studied the mode of spread on the pancreatic head carcinoma histologically in association with the patient survival period and the mode of cancer recurrence. The histological materials were 41 surgically resected specimens and 12 autopsied specimens. The mode of cancer spread were classified into 5 factors: continuous spreading along the caudal pancreatic duct wall; dysplastic lesion; multicentric cancer lesion; lymphatic infiltration; lymph node metastasis and direct invasion toward the retroperitoneal space. As a result, total pancreatectomy is considered as rationale only when continuous ductal infiltration spreads into the duct in pancreatic tail, but the cut margin of the pancreas should be 2 cm distant, at least, by the macroscopical observation. Additionally, frozen section of the cut line, cytological examinations of the pancreatic juice and duct epithelium in remaining pancreas should be negative. It was remarkable that the patient's prognosis depended upon the lymph-node involvement and retroperitoneal invasion at the surgical resection. Therefore, it is most important to do prophylactic resection of a soft tissue behind the pancreas including lymph nodes in the retroperitoneal space.

Adenocarcinoma, Papillary↗
PubMed1984

Role of the thymus in control of autoreactivity or allotolerance in syngeneic and allogeneic bone marrow chimeras treated with bacterial adjuvants.

Thy-1-bone marrow (BM) cells from C57BL/6 (B6) mice were transferred into thymectomized or non-thymectomized syngeneic B6----B6, allogeneic B6----C3H or semiallogeneic B6----(B6 X C3H)F1, irradiated mice, after which bacterial substances (bacillus Calmette Guérin [BCG] or Bordetella pertussis [Bp]) were administered within 3 days. The regulation of reactivity toward the host environment, i.e., autoresponsiveness in B6----B6 and allotolerance in B6---C3H, was investigated by monitoring a graft-vs-host (GvH)-like wasting syndrome, as well as the in vitro responsiveness of spleen cells from the reconstituted mice in a mixed leukocyte culture/cell-mediated lysis (MLC/CML) assay. The BCG-treated B6----B6 recipients developed a wasting syndrome and MLC/CML reactivity toward syngeneic target cells within 7 wk. This was never observed in BCG-treated but otherwise normal (i.e., nonreconstituted) mice, nor was it seen in any bone marrow chimeras that had been left without BCG treatment, irrespective of host/donor combination or thymectomy. The development of wasting syndrome as well as autoreactivity in BCG-treated B6----B6 mice could be prevented by thymectomizing the recipients before reconstitution or co-cultivating the donor BM cells with syngeneic spleen cells before reconstitution of nonthymectomized recipients. In the allogeneic or semiallogeneic combinations, the BCG treatment resulted in a wasting syndrome and CML/MLC reactivity toward C3H or (C3H X B6)F1 host-derived cells irrespective of thymic presence or absence. No breakdown of allotolerance, however, was retarded in the thymectomized mice, and it could be prevented by co-cultivation of donor BM cells with splenocytes of recipient genotype only if the cells were used to reconstitute thymectomized recipients. The breakdown of allotolerance in B6----C3H chimera was never accompanied by autoreactivity against B6 target cells. It is concluded that induction of autoreactivity and GvH in BCG-treated syngeneic BM chimeras, probably reflecting the breakdown of autotolerance, is strictly thymus dependent. In contrast, induction of anti-host reactivity in BCG-treated allogeneic chimeras may occur in the absence of a thymus and without concomitant autoreactivity, suggesting two independent levels of controls: one that is thymus dependent for the breakdown of auto- as well as allotolerance, and one that is thymus independent, unique for the breakdown of allotolerance.

Adjuvants, Immunologic↗
PubMed1984

The in vivo regulation of splenic T cell population by the prostaglandin-mediated system.

The effects of prostaglandins (PGs) on splenic T cell population, the generation of Con A-induced suppressor T cells, and antibody response to sheep erythrocytes were examined in mice in which the in vivo level of PG was regulated by indomethacin (INDO), an inhibitor of PG-synthesis, and exogenous PGE2. Inhibition of PG-synthesis enlarged the T cell population in the spleen and such an enlargement was due to an increase in Lyt-1+2+ and Lyt-1-2+ subsets. In this group, the induction of suppressor T cells was augmented, while the antibody response was suppressed. Elevation of the PG-level scarcely affected the size of the whole T cell population in the spleen but slightly increased a Lyt-1+2- subset. The production of suppressor T cells was disturbed, and the antibody response was augmented in this T cell population. Experiments using anti-Lyt antibody plus complement showed that Lyt-1+2+ subsets exhibited these distinctive activities between PG-decreased and PG-increased mice. A Lyt-1+2+ subset from mice with a high PG-level may be in an advanced stage of maturation compared with that from mice with a low PG-level under the promoting effect of PG on T cell differentiation. In vivo regulation of the PG-level appears to play an important role in the regulation of the T cell population and immune response.

Animals↗
PubMed1984

[Mechanism of energy transduction in Na+, K+-ATPase].

The author reviews the molecular properties of Na+, K+-ATPase not only to elucidate the reaction sequence of the enzyme, but also to obtain a better understanding of the mechanism of energy transduction. It is shown that the reaction sequence which had been proposed mainly from phosphorylation kinetics has now been proven by the direct measurement of dynamic fluorescence changes during the hydrolysis of ATP. The formation of MgNaE1 ATP and the transition of NaE1P to E2P accompany the largest fluorescence changes in both the intrinsic and the extrinsic probes, respectively. These findings seem to be a useful step for understanding the mechanism of energy transduction in Na+, K+-ATPase.

Adenosine Triphosphate↗
PubMed1984

Type of collagen in chordoma.

Pepsin-soluble collagen was extracted from three histologically proven cases of chordoma and nucleus pulposus. The collagen types of these materials were investigated by differential salting-out, SDS-PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis) of native collagen and their CNBr (cyanogen bromide) cleaved peptides, and their amino acid compositions. Although the collagen of nucleus pulposus was type II, that of chordoma was largely type I. Collagen of notochord, the origin of nucleus pulposus, is known to be type II. Further investigation is necessary in view of the fact that collagen of chordoma, a tumor believed to be derived from notochord, is not type II.

Aged↗