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Biomedical subjects

N Seki

Publications and source records attributed to N Seki.

At least 253 records · Page 14Linked to original sources
PubMed1989

[Cognition for visual perception of a student apprentice of dental hygiene to the presence of a parent beside the dental chair for dental treatment. The study of cognitive style and personality traits].

With a view to knowing how the dental hygienist looks at and makes cognition of a mother who is kept standing by her child just receiving his dental treatment, cognition from visual perception was examined, by dental hygienist apprentice. Possible difference in scene cognition process according to different cognition style of these subjects was also analyzed from the elements of eye-movement. On the basis of the results of a YG character test performed together, cognition styles and personality traits were examined additionally. The results obtained were as follows: 1. From the number of total scanned sites upon the observation of test movie, 9 and 6 subjects having reflective cognition style and impulsive cognition style, respectively could be divided out of all 43 subjects. 2. When the mother's countenance turned from calmness to uneasiness, the reflective style-group showed increased gaze at the mother's face. 3. When the mother's countenance turned from calmness to uneasiness, the impulsive style-group showed especially increased gaze at the child's face, with a tendency to gazing obviously biased toward his face. 4. The reflective style-group tended to have visual scanning strategies by which it observes each of the sites under test movie, while always contrasting them. 5. The impulsive style-group tended to have visual scanning strategies by which it observes one of the sites under test movie and then the other. 6. Compared with the reflective style-group, the impulsive style-group showed personality traits such as less depression, low general activity and weak initiative. 7. The above results revealed that a subject having impulsive cognition style found a difficulty in taking a wide view of the situation in which its mother is just present in the treating room and was easily put under visual influence of any change in its mother's countenance.

Adult↗
PubMed1988

Type II collagen-induced murine arthritis. I. Induction and perpetuation of arthritis require synergy between humoral and cell-mediated immunity.

Immunization of DBA/1 mice with type II collagen resulted in typical and progressive arthritis, which is associated with the production of high titer of anti-collagen antibody and the induction of cell-mediated immunity as exemplified by delayed type hypersensitivity response as well as lymphokine production. In contrast, administration of heat-denatured collagen into DBA/1 mice failed to induce the arthritis. These mice produced only marginal antibody, whereas they developed comparable cell-mediated immunity to that induced by immunization with native collagen, and therefore the inoculation of heat-denatured collagen provided the regimen capable of inducing preferentially cell-mediated immunity without the generation of high level of antibody. Inasmuch as administration of antibody induced only marginal and transient joint swelling not associated with typical histologic lesion, the synergistic effect of humoral and cell-mediated immunities was investigated using antibody preparation and the regimen to induce selectively cell-mediated immunity. The results demonstrate that administration of antibody into DBA/1 mice pre-sensitized with heat-denatured collagen resulted in potent and progressive arthritis. Such synergy was further confirmed by the induction of arthritis in T cell-depleted DBA/1 mice that had been adoptively transferred with antibody and lymphoid cells from heat-denatured collagen-sensitized mice. Moreover, it was revealed that the nature of cells capable of transferring cell-mediated immunity was of Thy-1+ and L3T4+ Lyt-2-. These results indicate that anti-collagen antibody and L3T4+ T cell-mediated cellular immunity are crucially required for the perpetuated development of type II collagen-induced arthritis.

Animals↗
PubMed1988

Electrical and mechanical properties of the capsular smooth muscles of the rabbit prostate in relation to the actions of the alpha 1-adrenoceptor blocker, YM-12617.

1. Electrical and mechanical properties of smooth muscle cells of the rabbit prostate capsule and the actions of the alpha 1-adrenoceptor blocker, YM-12617, were investigated using microelectrode and isometric tension recording methods. 2. The capsular muscles comprised thick and thin muscle bundles. In the former, noradrenaline (NA; 0.1-10 microM) provoked the phasic and tonic mechanical responses, with twitch contractions superimposed on the tonic response. YM-12617, in concentrations over 1 nM inhibited the contraction evoked by any given concentration of NA. Yohimbine (up to 10 microM) slightly inhibited the NA-induced contraction whilst clonidine (up to 10 microM) and acetylcholine (ACh; up to 10 microM) produced no mechanical response. 3. In thin muscle bundles, NA (0.1-10 microM) produced a contraction but the phasic response was small and the tonic response was negligible. These changes were blocked by YM-12617. In contrast, ACh (0.1-10 microM) produced atropine-sensitive, large phasic and tonic responses similar to those observed on application of NA to thick muscle bundles. 4. In thin and thick muscle bundles, the mean resting membrane potentials were -54 and -56 mV, respectively, values which were not statistically different. However, in thick muscle bundles, NA (over 0.1 microM) depolarized the membrane in a concentration-dependent manner and produced repetitive spike generation; ACh (up to 1 microM) did not modify the membrane potential. In thin muscle bundles, the above concentrations of NA hyperpolarized the membrane but ACh produced a large depolarization with repetitive spike generation. 5. In thick muscle bundles, nifedipine (0.3 microM) blocked twitch contractions generated spontaneously or provoked by application of NA with no effect on phasic and tonic responses. The NA-induced depolarization persisted after superfusion with nifedipine up to a concentration of 1.0 microM. In a Ca-free solution containing 2 mM EGTA, NA produced only the phasic responses, and re-addition of Ca (2.6 mM) restored the generation of a tonic response. 6. After application of 0.3 microM nifedipine, the effects of YM-12617 and prazosin were observed on the tonic component of the NA-induced contraction of thick muscle bundles. The ID50 values for YM-12617 and prazosin were 1 nM and 15 nM, respectively (n = 4). YM-12617 shifted the NA concentration-response curve to the right in a concentration-dependent and parallel manner. The Schild plot yielded a straight line with slope of 0.97 +/- 0.05, (n = 4). The pA2 value for YM-12617 was 10.4 +/- 0.05, (n = 4). 7. In thiqk muscle bundles, the depolarization induced by NA (1O microM) was blocked by YM-12617 (over 1 nM) to a greater extent than by prazosin (0.1 microM). Half-inhibition of the NA (10 microM)-induced maximum depolarization by YM-12617 or prazosin occurred at concentrations of 2 nm and 100 nM, respectively. 8. From these mechanical and electrical responses, the heterogeneous nature and distribution of alpha-adrenoceptors and muscarinic receptors has been elucidated in capsular smooth muscles in the rabbit prostate. In both thick and thin muscle bundles, NA-induced electrical and mechanical responses were more potently inhibited by YM-12617 than by prazosin.

Acetylcholine↗
PubMed1988

Effect of oral pretreatment with indomethacin on the intestinal first-pass metabolism of salicylamide in rabbits.

The effect of oral pretreatment with indomethacin on the intestinal first-pass metabolism of salicylamide (SAM) was studied in rabbits using in situ intestinal sacs with complete mesenteric venous blood collection. The appearance of both SAM and its metabolites into the mesenteric venous blood was measured directly by cannulating the mesenteric vein of exposed rabbit intestine and collecting all venous blood draining from the absorbing region. By oral pretreatment with indomethacin, the total amounts of SAM absorbed in 20 and 120 min were significantly increased compared to the control. These results indicated the alteration of the permeability in the intestinal mucosa. In 20 min, indomethacin pretreatment resulted in increased appearance of SAM and SAM glucuronide in the mesenteric venous blood. In 120 min, increased appearance of SAM and decreased appearance of SAM sulfate were observed, compared to the control. These findings suggested that the change in the intestinal first-pass metabolism of SAM is probably due to the intestinal mucosal damage by oral pretreatment with indomethacin.

Administration, Oral↗
PubMed1988

Alpha and beta adrenoceptor blocking action of carvedilol in the canine mesenteric artery and vein.

We observed the effects of carvedilol, a novel beta adrenoceptor blocker, on electrical responses of smooth muscle cells produced by endogenous and exogenous norepinephrine (NE) in isolated canine mesenteric artery and vein. Carvedilol inhibited the NE-induced depolarization in the artery but not in vein, with potencies equivalent to prazosin, i.e., carvedilol blocked alpha 1 adrenoceptors in arterial smooth muscles. Stimulation of perivascular nerves evoked an excitatory junction potential (e.j.p.) and a slow depolarization in these vascular smooth muscles. Carvedilol inhibited the slow depolarization evoked in the artery but not in the vein, with no marked inhibition of the e.j.p.s. High concentrations (10(-5) M) of carvedilol inhibited the e.j.p., slow depolarization, and also the compound action potentials of sympathetic nerve bundles running along the mesenteric vessels, suggesting that these inhibitions were due to local anesthetic actions. The e.j.p. amplitude was increased by isoprenaline and was decreased by NE. The NE and isoprenaline actions were antagonized by yohimbine and propranolol, respectively. Carvedilol inhibited the isoprenaline-actions but not the NE actions on the e.j.p., suggesting that this drug blocked prejunctional beta adrenoceptors but not the alpha 2 adrenoceptors. These results indicate that carvedilol blocks alpha 1 and beta adrenoceptors but not alpha 2 adrenoceptors in vascular tissues.

Action Potentials↗
PubMed1987

Leiomyosarcoma of inferior vena cava.

A case of leiomyosarcoma of the inferior vena cava is presented and pertinent clinical features of 57 reported cases in the English literature are reviewed.

Female↗
PubMed1986

Effect of auranofin on autoimmune disease in a mouse model.

The effect of an oral gold preparation, auranofin, on the autoimmune disease mouse MRL/l was examined. Oral administration of auranofin on consecutive days from 6 weeks of age reduced anti-DNA antibody production, IgM rheumatoid factor production, hypergammaglobulinemia, polyclonal B cell activation and renal disease, but did not prevent massive lymphadenopathy or restore the low level of either IL-2 production or mitogen response associated with 1pr gene. In contrast to the effect on autoantibody production, little suppressive activity on the immune response to exogenous antigen SRBC was observed. These results indicate that autoimmune disease in MRL/l mice can be prevented without abrogation of T cell abnormalities and that autoimmune-selective suppression can be induced by chemical compound(s) like auranofin.

Animals↗