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S Doi

Publications and source records attributed to S Doi.

At least 73 records · Page 4Linked to original sources
PubMed1998

Reverse transcription-polymerase chain reaction and immunohistochemical study of the expression of fibronectin mRNA in human submandibular salivary gland.

The alternative expression of fibronectin mRNA in submandibular salivary glands was analysed using three groups of polymerase chain reaction probes to amplify the cell-binding domain (CBD), and the extra domain (ED)-A and ED-B exon regions in five normal human adults. The fibronectin CBD region was fairly well expressed in the salivary gland while less than trace amounts of ED-A and ED-B exons were expressed. Immunohistochemical staining with an antihuman plasma fibronectin monoclonal antibody, which recognized specifically the CBD region, demonstrated definite positive cytoplasmic staining in the duct-cell area. On the other hand, an anticellular fibronectin ED-A-specific monoclonal antibody was very low positive in duct cells. The results suggest that salivary fibronectin is synthesized in the submandibular salivary gland only, and does not include the ED-A segment. Furthermore, duct cells also produced fibronectin without ED-A.

Adult↗
PubMed1998

Effect of maternal hydration on oligohydramnios: a comparison of three volume expansion methods.

OBJECTIVE: To determine the effect of maternal hydration with intravenous (i.v.) isotonic fluid, i.v. hypotonic fluid, and oral water on amniotic fluid index (AFI) in women with oligohydramnios. METHODS: Patients with low AFI and gestational age over 35 weeks without maternal complications were randomized into four groups (2 L/2 h i.v. isotonic fluid, 2 L/2 h i.v. hypotonic fluid, 2 L/2 h oral water, control). Maternal plasma osmolality, AFI, hematocrit, and hemoglobin concentration were measured before and after hydration. RESULTS: Eighty-four patients (n=21/group) completed the study without any maternal adverse effects. The mean increase in AFI after hydration was significantly greater in the i.v. hypotonic and oral water groups (2.8+/-1.9, P < .001; 3.8 +/-1.9, P < .001, respectively), but not in the i.v. isotonic group (0.5+/-1.1), compared with the control group (0.5+/-1.1). Significant decreases in maternal hematocrit and hemoglobin concentration were found only after i.v. isotonic hydration (32.0+/-2.9 to 29.5+/-2.3, P < .001; 11.0+/-1.6 to 10.1+/-1.4, P < .001, respectively). Changes in maternal osmolality correlated with the changes in AFI in both the i.v. hypotonic group (r=.58, P < .001) and oral water group (r =.63, P < .001). CONCLUSION: Maternal hydration with either i.v. hypotonic fluid or oral water increases AFI in oligohydramnios. Maternal osmotic change rather than maternal volume expansion had a more direct impact on increasing amniotic fluid volume with short-term acute hydration.

Adult↗
PubMed1998

Continuous and simultaneous cultivation of benthic food diatom Nitzschia sp. and abalone Haliotis sieboldii by using deep seawater.

By using low-temperature, clean, and nutrient-rich properties of deep seawater (DSW; seawater below the euphotic layer), a continuous and simultaneous cultivation system for a benthic food diatom, Nitzschia sp., and juvenile abalone was established. Cell suspension of Nitzschia sp. was added to a bioreactor made of acrylic pipe (7 cm diameter x 50 cm long) containing short vinyl tubes (2 cm diameter x 2 cm long) as substrata. DSW collected from 320 m depth at Muroto City, in Kochi Prefecture, Japan, was supplied to the reactor and incubated under natural light (ca. 6000 lux) with a continuous DSW flow rate of 40 turnovers per hour. After growing enough benthic diatoms in the reactor, juveniles of abalone, Haliotis sieboldii (shell length ca. 10-20 mm) were put into a reactor, and cultivated simultaneously with food diatoms in the continuous flow system. During the four-month incubation, 7-month-old abalone juveniles with a shell length of 12.4 (average) +/-0.2 (SD) mm were grown to 19.4 (+/-1.7) mm in the reactor. Daily growth rates of abalones were 50-110 µm/day. These results indicate that the continuous cultivation system with DSW supports the growth of juvenile abalone without any supply of seaweed until it grows to release size.

Journal Article↗
PubMed1997

On the behavior of mRIC--a simple model of living pacemakers driven by periodic pulse trains.

The main feature separating a living pacemaker from other oscillators is the fact that the former has not only the oscillatory property but also slow and fast changes of the membrane potential corresponding to the sub- and suprathreshold regions. We propose a simple mathematical model called mRIC and show that the model exhibited the essential feature of pacemakers generating spikes at constant time intervals. The behavior of the model driven by periodic pulse trains is analysed using the phase transition curve.

Biological Clocks↗
PubMed1997

Complex responses of living neurons to pacemaker inhibition: a comparison of dynamical models.

A neuron can respond to periodic inhibitory input with a variety of complex behaviors, periodic and aperiodic. We present a succession of models to test hypotheses for mechanisms underlying complex behavior generation. Model comparison using non-linear dynamics techniques indicates that long-duration IPSP aftereffects and spiking behavior are necessary for most of the basic response properties, though not sufficient for some of their more subtle aspects.

Action Potentials↗
PubMed1997

Precordial leads QRST time integrals for evaluation of right ventricular overload in children with congenital heart diseases.

It was previously shown that body surface QRST isointegral maps of the anterior chest were abnormal in patients with right ventricular overload and that the abnormalities varied with hemodynamic status. The QRST isointegral maps were first characterized by using a departure index map for normal controls. The study group consisted of 14 patients with pulmonary stenosis (PS), 20 with tetralogy of Fallot, (TOF) and 43 with atrial septal defect (ASD). The QRST isointegral maps of these three groups were compared with the data on 23 to 65 age-matched normal children. In mean departure index maps, the patients with right ventricular pressure overload (PS or TOF) showed an increase in departure index on the anterior midchest, while those of right ventricular volume overload (ASD) showed two maxima on the anterior and left lateral chest, with a trough-like negative area between them. Since the abnormal findings were seen on the anterior chest, we evaluated the diagnostic usefulness of QRST time integral values for precordial leads of the routine electrocardiogram (ECG) in a second part of this study. The precordial QRST time integral values from 9 patients with PS and 11 with TOF (0-2 years of age, mean 1.1 years) and 22 ASD patients (6-15 years, mean 10.1 years) were compared with those of the age-matched control children. The QRST time integral values of the precordial leads in right ventricular pressure overload were significantly increased in the right precordial leads (V1, V2). In right ventricular volume overload, the QRST time integral values of the V1, V2, V4, and V6 leads demonstrated a significant deviation from those of the control group. Therefore, a discrimination formula was constructed by using the values of these leads, and the criteria derived from this formula revealed good (98%) diagnostic accuracy. In detection of right ventricular overload, the QRST time integral values of the precordial lead ECG, if confirmed in a larger data set, may be useful as a simple screening method.

Adolescent↗
PubMed1997

Intraalveolar expression of tumor necrosis factor-alpha gene during conventional and high-frequency ventilation.

The effects of conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFO) on intraalveolar expression of the tumor necrosis factor-alpha (TNF-alpha) gene were studied in surfactant-depleted rabbits. After lung lavage with saline, 13 rabbits were administered either CMV (n = 6) or HFO (n = 7) for 1 h at an FiO2 of 1.0 and a mean airway pressure of 13 cm H2O. Lung lavage was then repeated. The rabbits' RNA was extracted from the lavage cells, and mRNA for TNF-alpha was quantitated by reverse-transcription polymerase chain reaction using glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as an internal standard. At 1 h of ventilation, PaO2 was slightly lower with CMV than HFO, while lavage cell counts and cytology were similar between the two groups. The ratio of TNF-alpha mRNA to GAPDH mRNA increased with CMV (control, 0.48 +/- 0.04 [SE] versus 1 h, 1.02 +/- 0.14, p < 0.01) but did not change with HFO (0.55 +/- 0.07 versus 0.73 +/- 0.09). In a separate series of experiments, ten surfactant-depleted rabbits continued to be ventilated for 4 h either by CMV (n = 5) or HFO (n = 5). Conventional mechanical ventilation resulted in a progressive hypoxemia, decreased lung compliance, increased number of neutrophils in lung lavage fluid, and substantial morphological changes including hyaline membrane formation and neutrophil accumulation, whereas HFO was associated with minimal changes in such physiological and pathological abnormalities. These results suggest that activation of alveolar macrophages and production of proinflammatory cytokines may play a pivotal role in the early stage of ventilator-induced lung injury, and that ventilator mode (CMV or HFO) substantially modulates macrophage activation and hence the degree of lung injury.

Animals↗
PubMed1997

Clinical importance of interleukin-2 receptor alpha-chain expression in acute leukemia. The Japan Cooperative Group of Leukemia/Lymphoma.

To clarify the clinical importance of interleukin-2 (IL-2) receptor (IL-2R) expression in acute leukemia, we examined 517 adult patients with acute leukemia and CML blast crisis (CML-BC). IL-2R alpha was expressed in 42/311 AML, 5/11 acute unclassified leukemia, 24/116 pre-B ALL, 2/32 T-ALL, and 27/47 CML-BC, while IL-2R beta was expressed only in 2 T-ALL. Expression of IL-2R alpha was closely associated with that of different lineage markers, CD11b, CD34, and Ph1+ abnormality. IL-2R alpha(+) non-T leukemic cells did not respond to IL-2. Clinical outcome of IL-2R alpha (+) leukemia showed lower response to conventional chemotherapy and poorer prognosis than IL-2R alpha (-) cases. Serum IL-2R alpha level in IL-2R alpha (+) cases increased at the onset. Our findings indicate the diagnostic importance of IL-2R alpha expression in acute leukemia as a prognostic risk factor with a close relation to the particular cellular characteristics.

Acute Disease↗
PubMed1997

Expression of cyclins D1 and E in human colon adenocarcinomas.

Cyclins D1 and E play critical roles in the progression of cells through the G1 phase of the cell cycle. Amplification and/or overexpression of the cyclin D1 gene and aberrant expression of cyclin E have been described in several forms of human cancer. In the present study, we examined the expression of these two genes by Western, Northern and Southern blot analyses in a series of primary human colon carcinomas of various stages and degrees of differentiation and in paired adjacent normal mucosa samples, and also in a series of human colon carcinoma cell lines. About 50% of the colon carcinomas displayed a two to five fold increase in the expression of cyclin D1 mRNA and protein, when compared with the paired normal mucosa samples. Six out of eight carcinomas examined showed a four to nine fold increase in cyclin E mRNA and about 50% of the carcinomas displayed a two to three fold increase in cyclin E protein. Low molecular weight cyclin E-related proteins were observed in four out of ten carcinomas. These changes in cyclins D1 and E occurred in both early and late stage tumors. Three of the six cell lines examined displayed a high expression of cyclin D1 mRNA and protein. A very high level of cyclin E mRNA expression was seen in HCT116 cells and this was associated with the presence of low molecular weight cyclin E-related proteins. None of the primary colon carcinomas nor the six cell lines examined displayed amplification of either the cyclin D1 or cyclin E genes. Thus, an aberrant expression of both cyclins D1 and E occurs in a significant fraction of human colon carcinomas.

Adenocarcinoma↗
PubMed1996

Effect of physical activity as a caddie on ultrasound measurements of the Os calcis: a cross-sectional comparison.

This cross-sectional study investigated the effect of long-term activity as a caddie on ultrasonic properties of the os calcis. We measured 74 healthy women, age 20-59 years, who worked at a golf course as caddies. An age-matched control group of 433 healthy women, who were office workers or housewives, also were recruited for comparison. The ultrasound measurements were performed with an Achilles ultrasound densitometer. The quadriceps muscle strength and the hand grip strength were measured in a perimenopausal subgroup (45-59 years) of the caddies and a subgroup of controls matched for age, height, weight, and body mass index. Urinary pyridinoline and deoxypyridinoline were also measured in these perimenopausal subgroups. Caddies had significantly higher ultrasound values than controls in the 40-49 (stiffness index, 101.6 +/- 12.9% versus 87.9 +/- 11.9%; p < 0.0001) and 50-59 (stiffness index, 90.5 +/- 11.6% versus 77.2 +/- 11.6%; p < 0.0001) age-stratified groups. Quadriceps strength and grip strength were significantly higher in caddies than those in controls. In postmenopausal caddies, all ultrasound values were significantly higher than for controls. In caddies there were not significant decreases of any ultrasound values with postmenopausal age. Even for the subgroup within 3 years of menopause there were significant differences between caddies and controls (p < 0.01). There were no significant increases of pyridinoline and deoxypyridinoline after menopause in the caddies. We demonstrated that the caddies had higher ultrasound properties of the os calcis and lower bone resorption after menopause compared with controls.

Adult↗
PubMed1996

CD4 T-lymphocyte activation is associated with peak expiratory flow variability in childhood asthma.

BACKGROUND: Asthma has been recognized as a chronic inflammatory disorder of the airway. We have investigated the relationships among the activation markers on lymphocytes, eosinophils, their serum products in the peripheral blood, and the variability of airway obstruction in childhood asthma. METHODS: Twenty-two patients with atopic asthma (mean age, 12 years) were treated regularly and asked to measure their peak expiratory flow (PEF) twice daily for 7 days, Peripheral venous blood was obtained on day 8. RESULTS: The absolute counts of CD4 T lymphocytes expressing the activation marker CD25 in the peripheral blood on day 8 correlated significantly with the values of the coefficient of variation (CV) of both morning PEF (p < 0.01) and night PEF (p < 0.05) obtained over 7 days, but those of CD8+/CD25+ T lymphocytes, those of CD23+ B lymphocytes, and the serum concentrations of soluble CD25 did not. The absolute counts of peripheral blood eosinophils also demonstrated a significant correlation with the CV values of both morning PEF (p < 0.01) and night PEF (p <0.05). CONCLUSION: CD4 T-lymphocyte activation and increased counts of eosinophils in peripheral blood correlate with CV of PEF in patients with asthma, suggesting that CV of PEF is a good marker for assessing not only the variability of airway obstruction but also the degree of airway inflammation.

Adolescent↗
PubMed1996

Histone hyperacetylation plays a role in augmentation of IL-4-induced IgE production in LPS-stimulated murine B-lymphocytes by sodium butyrate.

We previously reported the augmentation by sodium butyrate (NaBu) of IL-4-induced IgE production in LPS-stimulated murine B-lymphocytes. Histone deacetylase inhibition may be involved in the molecular mode of action of NaBu. Thus, this study was accomplished to examine the involvement of histone hyperacetylation in IL-4-induced class switching promotion by NaBu with a specific histone deacetylase inhibitor, trichostatin A (TSA). TSA was found to enhance IL-4-dependent IgE production in a concentration-dependent manner (0.3-30 nM) as did NaBu, although neither compound affected the IgE production in the absence of IL-4. The effect of combined addition of suboptimal concentrations of NaBu and TSA to the culture appeared to be additive, not synergistic. Moreover, the intense of enhancement of IgE production observed by addition of both compounds at optimal concentrations appeared to be equivalent to that obtained with each maximal concentration. Furthermore, enhancement of IgE production by TSA or NaBu was confirmed to be absolutely IL-4 dependent and was not due to the shift of kinetics. On the other hand, various cell cycle inhibitors such as caffeine and theophylline (G1 or G2-arrest), hydroxyurea (S-arrest), and colchicine (M-arrest), none of which have the ability to inhibit histone deacetylase, were shown to have no effect. These findings suggest that histone hyperacetylation plays an important regulatory role in the modification of IL-4-dependent class switching to C epsilon in LPS-stimulated murine B-cells by NaBu.

Animals↗
PubMed1996

Langerhans cells in mice with severe combined immunodeficiency (SCID).

The existence of Langerhans cells in the stratified squamous epithelium of severely combined immunodeficient (SCID) mice was studied by enzyme histochemistry, immunohistochemistry and electron microscopy. Considerable numbers of ATPase-positive Langerhans cell were observed in the epidermis (ear and hind limb) as well as in the stratified squamous mucosal epithelium (forestomach and tongue) of SCID mice. The cells also expressed Ia antigen. This indicates that, in spite of the lack of functional T and B lymphocytes, the antigen-presenting function of Langerhans cell was retained in SCID mice. In the epidermis, frequency of Ia expressing Langerhans cells was low, but in the forestomach epithelium, 90% of Langerhans cells had strong Ia positivity. In the forestomach epithelium of SCID mice, the regulation of Langerhans cell maturation was affected differently from the epidermis. As with normal mice, the occurrence of Langerhans cell in female SCID mice was higher than in males; hormonal immuno-regulations may be normal in SCID mice. Under electron microscopy, many Birbeck granules were observed in epidermal Langerhans cells but few in those of the mucosal epithelium. In SCID mice, Langerhans cell exists constitutively in the epidermis and mucosal epithelium, where the cell may function in a defense system independent from T and B lymphocytes.

Adenosine Triphosphatases↗
PubMed1996

[Difference of lung deposition rate of disodium cromoglycate (DSCG) among three kinds of electric nebulizer].

We examined the lung deposition rate of DSCG with three kinds of electric nebulizer (NE-U03, Pari-Master, Nisshou) on 5 pediatrician skilled with inhalation therapy (31-54 years of age). Excretion of DSCG for 4 hours after inhalation in urine were highest in NE-U03 group, second in Pari-Master group and least in Nisshou group. And then we studied bronchodilating effect of sulbutamol on 18 children (7-17 years of age) with acute exacerbation of bronchial asthma with NE-U03 and Pari-Master. Asthmatic symptom score, SaO2 and pulmonary function were examined before and after inhalation. The delta %FVC, delta %FEV1.0, delta %PEF, delta %V50 and delta %V25 using NE-U03 were 10.3%, 19.1%, 25.5%, 32.5%, and 29.3% in NE-U03 group and 10.6%, 15.9%, 24.1%, 25.4% and 21.3% in Pari-Master group. The data of pulmonary obstraction in NE-03 group were better than that in Pari-Master group. From our data it is obvious that 3 kinds of electric nebulizers have different efficacy in regard to the lung deposition dose of inhaled drugs. When we compare the efficacy of drugs. When we compare the efficacy of drugs for nebulizer inhalation therapy, we should use the drug dose attained to lung and not nominal drug dose in principle.

Adolescent↗