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Y Hoshina

Publications and source records attributed to Y Hoshina.

29 records · Page 2Linked to original sources
PubMed1984

[Basic studies on the potential changes in the eyelid elicited by flash stimulation, especially related to the adaptation of the eye].

In order to establish the most adequate method to lead the photically evoked lid potential changes, their physiological properties were studied from standpoint of dark or light adaptation, which is known to be due to the increase or decrease in the sensitiveness of the retina that is the receptor of the orbicularis oculi reflex. The photically evoked lid potential changes were obtained with the summation technique by the signal processor (7 T 0 8, SAN-EI, Tokyo) in normal subjects. In addition, the average summated responses of the photically evoked lid MV responses, the ERG, EOG and EEG were also recorded simultaneously and discussed polygraphically. The results obtained were as follows: The average evoked lid potential changes in healthy resting subjects with eyes closed were shown to be composed of early rapid component, initial slow component and late slow component, which corresponded to dominant rapid vibrations of the evoked lid MV responses, the a and b waves of ERG and the EOG, respectively. The electromyographic and electrooculographic components were observed to have peak latency of about 60 msec and 200 msec, respectively. The electromyographic and electrooculographic components were found to change corresponding to the level of cortical activity indicated by the EEG patterns. They were gradually suppressed in amplitude according to the decrease of cortical activity and disappeared in stage 2 of natural sleep, although the electroretinographic components remained. With the progress of dark adaptation after adapting from light to darkness, the electromyographic and electrooculographic components in addition to the electroretinographic component of the average lid potential changes were considerably increased in amplitude but hardly changed in peak latency.(ABSTRACT TRUNCATED AT 250 WORDS)

Dark Adaptation↗
PubMed1984

[Basic studies on the potential changes in the eyelid elicited by flash stimulation, especially the intensity of flash light stimulation].

The average photically evoked lid potential changes are known to consist of electromyographic components due to the orbicularis oculi reflex, electroretinographic and electrooculographic components, which corresponded to the average summating responses of the lid MV responses, electroretinogram (ERG), electrooculogram (EOG), respectively. In the present study the photically evoked lid potential changes were studied from the standpoint of the stimulus strength in healthy subjects and patients with an artificial eyeball. The photically evoked lid potential changes were obtained with the summation technique under various physiologic and pathologic conditions. In addition, the average summating responses of the lid MV responses, EOG, ERG and EEG were also recorded simultaneously and discussed polygraphically. The average evoked lid potential changes in healthy resting subject with eyes closed were shown to be composed of the electromyographic components dependent on the effector activity of the orbicularis oculi reflex, early and late slow components which corresponded to the ERG and the EOG respectively. The threshold stimulus necessary to elicit the electroretinographic, electromyographic and electrooculographic components was the intensity of flash stimulation, that is about 0.1, 0.3 and 4 joule in energy delivered to the stroboscope respectively. These components were observed to be increased in amplitude gradually according to the intensity strengthened. In the average lid potential changes obtained by random flash stimulation to a single eye, the electroretinographic components in the occluded side disappeared completely, but the other components were clearly observed and gradually increased in amplitude according to the intensity strengthened, although they were considerably decreased in amplitude than those obtained in the contralateral side of normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Abnormal expression of apoptosis-related antigens, Fas and bcl-2, on circulating T-lymphocyte subsets in primary Sjögren's syndrome.

OBJECTIVE: To clarify the pathological role of the apoptosis-related molecules expressed on peripheral blood (PB) lymphocyte subsets in primary Sjögren's syndrome (SS). METHODS: The levels of apoptosis-regulating proteins, Fas and bcl-2, were determined in the PB lymphocyte subsets from 21 patients with SS and 14 healthy controls by 2-color flow cytometry. RESULTS: In the PB from SS patients, lymphocytopenia, especially CD4+ cell-lymphocytopenia, was prominent. As observed in previous studies, the percentages of CD4+ CD45RA+ cells were lower in the SS patients than in the controls, while activated (DR+) cells were increased in CD4+ cells from the patients. Fas+ cells were also increased in the patients' CD4+ cells and CD8+ cells, but not in their B cells or natural killer cells. Furthermore, we observed several positive correlations among the percentages of activated cells (DR+ cells or CD45RA-cells) and Fas+ cells recognized in the CD4+ and/or CD8+ cells from the patients. On the other hand, intra-cellular bcl-2 proteins measured as mean fluorescence intensity were significantly diminished in the CD4+ cells, CD8+ cells, CD19+ cells, CD45RO+ cells and Fas+ cells from 14 SS patients compared with 12 healthy controls. In addition, the numbers and/or percentages of CD4+ cells and Fas+ cells positively correlated with their expression of bcl-2 in SS patients. CONCLUSION: The abnormal balance between Fas and bcl-2 expression detected in the PB lymphocyte subsets from SS patients relates, at least partially, to the lymphocytopenia observed in the patients.

Adult↗
PubMedDate not supplied

Serum matrix metalloproteinase-3 and fibrin degradation product levels correlate with clinical disease activity in rheumatoid arthritis.

OBJECTIVE: Plasmin and matrix metalloproteinase-3 (MMP-3) have been linked to articular destruction in rheumatoid arthritis (RA). We compared circulating levels of plasmin-mediated fibrin degradation product (FDP D-dimer) and MMP-3 with traditional parameters of disease activity in RA to determine their clinical utility. MATERIALS AND METHODS: Serum levels of MMP-3 and D-dimer were determined by enzyme-linked immunoassays in 60 patients with RA. Twenty healthy females and 21 patients with systemic lupus erythematosus (SLE) served as controls. RESULTS: MMP-3 (436.8 +/- 474.2 ng/ml) and D-dimer levels (351.2 +/- 296.3 ng/ml) were markedly elevated in the sera from RA patients as compared with healthy controls (43.9 +/- 15.2 ng/ml and 63.0 +/- 64.1 ng/ml, p < 0.0001, respectively). Both levels strongly correlated with each other (r = 0.627, p < 0.0001) and were closely associated with various clinical parameters for the disease activity of RA, including the erythrocyte sedimentation rate (ESR) and the Lansbury's activity index (p < 0.0001). MMP-3 levels were more highly correlated with articular parameters such as the swollen and painful joint counts (r = 0.454, p = 0.0002), whereas D-dimer levels correlated well with C-reactive protein (CRP) levels (r = 0.581, p < 0.0001). In SLE patients, MMP-3 (239.1 +/- 199.6 ng/ml, p < 0.0001) and D-dimer levels (86.9 +/- 85.2 ng/ml, p = 0.0278) were also higher than in healthy controls. Both levels correlated with each other (r = 0.612, p = 0.0025), and were associated with ESR and CRP levels, as was observed in RA patients, but not with most of the other clinical indicators for SLE. CONCLUSIONS: Serum levels of MMP-3 and D-dimer are clinically useful indicators for disease activity in RA. Our results further support the hypothesis that MMP-3 and plasmin may interact in the inflammatory synovial tissues, and thus augment the articular destruction seen in RA. In SLE patients, however, MMP-3 producing cells could be different from in RA patients, and further studies will be required to clarify the pathogenetic mechanism underlying the raised serum levels of MMP-3 and/or D-dimer.

Adult↗
PubMedDate not supplied

Anti-agalactosyl IgG antibodies and isotype profiles of rheumatoid factors in Sjögren's syndrome and rheumatoid arthritis.

OBJECTIVE: Rheumatoid factors (RFs) in sera from rheumatoid arthritis (RA) patients bind better to agalactosyl IgG [gal(-) IgG] than to native IgG. Recently, a novel lectin-enzyme immunoassay (LEIA) which can detect all isotypes of the immunoglobulins was developed in Japan. Since RFs are also detectable in Sjögren's syndrome (SS), we determined anti-gal(-) IgG antibodies and RF isotypes in sera from primary or secondary SS and RA patients to elucidate the clinical significance of these antibody profiles. METHODS: A series of 128 patients with primary SS (35 pts.), RA (57 pts.), or secondary SS [n = 36 pts., the SS being associated with RA (RA-SS) in 12 pts., systemic lupus erythematosus (SLE-SS) in 17 pts., and mixed connective tissue disease (MCTD-SS) in 7 pts.] and 38 healthy females were examined. Anti-gal(-) IgG antibodies were measured with a LEIA kit (ED055) using human gal(-) IgG as antigen. IgG-, IgA- and IgM-RF were determined with an enzyme-linked immunosorbent assay kit using human IgG-Fc as antigen. RFs were also examined by a conventional assay (laser nephelometry; LN-RF). RESULTS: Serum anti-gal(-) IgG antibody titers were higher in RA than in primary SS, SLE-SS or MCTD-SS, but the incidence of the antibodies did not differ between RA and primary SS. In both RA and primary SS, the antibodies were positive in half of the LN-RF-negative patients, and were also detected in almost all of those patients who had at least one of the RF isotypes. LN-RF, IgG-RF, IgA-RF and IgM-RF were present more frequently and their titers were higher in RA than in primary SS, but IgA-RF levels were similar in both groups. In RA-SS, all of the antibody titers were notably higher than in RA or primary SS. In RA and primary SS, IgA-RF and IgM-RF were common RF isotypes, and anti-gal(-) IgG antibody levels correlated well with LN-RF, IgA-RF and IgM-RF levels. These antibody profiles did not relate to any of the clinical parameters in RA, but all the antibody titers correlated with anti-SS-A/Ro antibody levels in primary SS. CONCLUSIONS: The anti-gal(-) IgG antibodies are not specific for RA; they are also frequent in SS. Our LEIA for antibodies is a very sensitive method to detect all RF isotypes in both RA and SS. Most of the antibody profiles are common to both diseases, although antibody titers are higher in RA, especially in RA-SS.

Adult↗