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Biomedical subjects

M Ichijo

Publications and source records attributed to M Ichijo.

At least 91 records · Page 5Linked to original sources
PubMed1989

IL-2 receptor expression and function on human cord blood mononuclear cells following PHA and anti-CD3 antibody stimulation.

Interleukin-2 receptors (IL-2R) on mononuclear cells from human umbilical cord blood were investigated after stimulation by phytohemagglutinin (PHA) and anti-CD3 antibody. The proportion of cells expressing the Tac antigen (IL-2R alpha, p55) did not differ from that for adult mononuclear cells. However, the levels of high affinity IL-2R (H-IL-2R) and low affinity IL-2R (L-IL-2R) present on the PHA blasts of cord blood cells were shown to be twice and three times, respectively, that of adults by interleukin-2 (IL-2) binding assay. The level of low affinity IL-2R in the cord blood cells was approximately double that of adult cells after activation by anti-CD3 antibody, but no difference was observed in the levels of high affinity IL-2R. Functional investigation of IL-2R revealed that the amount of internalized IL-2 in PHA-stimulated cord blood mononuclear cells was twice that in adult mononuclear cells but there were no differences between them in the time course of internalization and degradation. Although there were significant numbers of H-IL-2R in premature (25 and 28 weeks) infants following PHA stimulation, there were markedly fewer following anti-CD3 stimulation. Prematurity of the T-cell activation system through the CD3 pathway at this stage is therefore indicated.

Adult↗
PubMed1989

Bottle-feeding can prevent transmission of HTLV-I from mothers to their babies.

Breast-feeding is a major factor in the vertical transmission of human T-lymphotropic virus type I (HTLV-I). We studied whether such transmission may be prevented by bottle-feeding. HTLV-I infection was detected by both HTLV-I antigen and antibody tests. Thirty bottle-fed babies were examined 24 months after birth; only one was found to be HTLV-I antigen-positive. This infection rate was lower than that for breast-fed babies in whom HTLV-I antigen was detected in 24 of the 31 24-month-old babies born to HTLV-I positive mothers in a previous study. These results suggest that most vertical transmission of HTLV-I is attributable to breast-feeding and can be prevented by bottle-feeding.

Bottle Feeding↗
PubMed1989

Detection of HTLV-I genome in seronegative infants born to HTLV-I seropositive mothers by polymerase chain reaction.

We applied the polymerase chain reaction (PCR) method to detect gag, env and pX sequences of human T cell leukemia virus type I (HTLV-I) provirus in peripheral blood lymphocytes of seronegative infants born to HTLV-I seropositive mothers. Out of 22, five subjects were found to contain the HTLV-I provirus genome. Two of the five cases were judged to be negative for not only anti-HTLV-I antibodies but also the viral antigens on cultivated lymphocytes by the conventional antibody/antigen detection methods. These results indicate that PCR is of great use as a simple and highly sensitive method detect HTLV-I infection.

Adult↗
PubMed1989

Effect of freeze-thawing breast milk on vertical HTLV-I transmission from seropositive mothers to children.

Breast feeding is known to be a major cause of vertical transmission of HTLV-I from mothers to her children. The infectiousness of HTLV-I in breast milk was reported to be lost during freezing and thawing processes. We therefore administered frozen-and-thawed breast milk of HTLV-I carriers to their babies. Among the 13 babies given the frozen-and-thawed breast milk (now 12 months of age), no infection has been found yet. This result suggests that freezing and thawing of breast milk is a promising method for the prevention of vertical HTLV-I infection to breast-fed babies.

Breast Feeding↗
PubMed1989

Characterization of the CA125 antigen secreted from a newly established human ovarian cancer cell line (SHIN-3).

A cell line (designated SHIN-3) was established from a 56-year-old Japanese woman diagnosed as having serous cystadenocarcinoma of the ovary. SHIN-3 produced the tumor marker, CA125. When samples were subjected to one-dimensional gel electrophoresis followed by immunoblotting with anti-CA125 antibody, antigen binding appeared in the low-molecular-mass fraction around 50 KDa as well as in the high-molecular-mass fraction (more than 200 KDa). Subsequent resolution of this lower-molecular-mass component by two-dimensional gel electrophoresis gave rise to bands of 49 KDa near an isoelectric point of 7.3. Treatment of the CA125 antigen with 10 mM periodic acid resulted in no loss of activity. However, reduction and alkylation in 6 M guanidine-HCl or treatment at 100 degrees C for 20 min resulted in complete loss of activity. Treatment with various glycosidases did not inhibit activity, whereas digestion with proteases (except for papain) produced complete loss of activity, suggesting that the CA125 antigenic determinant is composed of conformationally dependent peptides.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1989

The problem of hemoglobin switching in premature infants and IUGR infants.

Understanding the hemoglobin switching regulation mechanism in extremely premature infants is particularly important for understanding the extrauterine adaptation of the infants. In this study, we sought to identify factors influencing oxygen affinity in fetal blood and neonatal blood and obtained these results. (1) Aging is required for hemoglobin switching. (2) Switching in premature infants (27 to 32 weeks) is delayed at least 3 weeks in comparison with full-term infants. (3) A delay in the switching of fetal hemoglobin to adult hemoglobin was confirmed in IUGR (intrauterine growth retardation) infants. However, there is a compensatory increase in 2, 3-DPG for adaptation after birth. (4) A delay in 2, 3-DPG increase was observed in RDS (respiratory distress syndrome) infants, and oxygen affinity remained high.

2,3-Diphosphoglycerate↗
PubMed1989

Hyperperfusion of cerebral cortex, thalamus and basal ganglia during spontaneously occurring migraine headaches.

Color-coded, cross-sectional imaging of local cerebral blood flow (LCBF) was made in a prospective manner among 22 patients with well-established common or classic migraine utilizing the stable xenon-enhanced computed tomographic (Xe CT-CBF) method. LCBF in patients during spontaneously occurring headaches (N = 12) were significantly higher compared to patients without headache (N = 10) by 25-35%. The hyperperfusion involved not only cerebral cortex but also subcortical structures including thalamus, basal ganglia, and subcortical white matter. LCBF increases were not bilateral and sometimes asymmetrical, but LCBF increases were not consistently related to the preponderant side of headache. No significant differences were observed in the degree or pattern of cerebral hyperperfusion during headaches compared among common (N = 6) and classic (N = 6) migraineurs. Results suggest a common etiology for both common and classic migraine. Results are not consistent with spreading oligemia or spreading cortical depression as a cause of migraine. The cerebral hyperperfusion appears to be mediated by various neurogenic and chemical changes accompanying migraine. The unilateral nature of migraine head pain is more likely due to dilation of extracranial vessels.

Adult↗
PubMed1989

[The study on the platelet aggregation inhibition activity of placental brush border (the mechanism of platelet aggregation inhibition)].

To clarify the role of placental brush border in the regulation of placental microcirculation, we investigated the platelet aggregation inhibition activity of placental brush border membrane vesicles (BBMV) and obtained the following results. 1. There was very strong platelet aggregation inhibiting activity in placental BBMV. In the 20-40 micrograms/ml protein concentration, the BBMV almost completely inhibited the platelet aggregation induced by ADP, arachidonic acid and collagen, and in the 100-150 micrograms/ml protein concentration, the BBMV almost completely inhibited the platelet aggregation induced by ristocetin. 2. There existed a very strong ADP degrading activity (ADPase activity) in the placental BBMV. The platelet aggregation activity of ADP was completely lost when ADP was preincubated with the placental BBMV. 3. The placental BBMV inhibited platelet malondialdehyde (MDA) production. With the 20 micrograms/ml and 100 micrograms/ml protein concentrations of placental BBMV, 22% and 65% of platelet MDA production was inhibited respectively.

Adenosine Diphosphate↗
PubMed1989

[Study of the mechanism of tumor marker CA125 in serum].

Ascites fluid, chest effusion, cyst fluid, and serum mainly obtained from malignant-ovarian-cancer patients were applied to quantitate the concentration of the tumor marker CA125. The same procedure was also performed for ascites, cyst fluid, and serum mainly obtained from benign-ovarian-tumor patients. To know how CA125 proceeds from tumor cells into the circulation, a CA125-producing, ovarian-cancer-cell line (SHIN-3) was transplanted sub-cutaneously into nude mice. Then the relationship between the grown tumor size and CA125 concentration in serum was analyzed and the histo-pathological background was also evaluated. Quantitative analysis of the ascites and cyst fluid showed no remarkable difference between the malignant-tumor patients and benign ones: however, the CA125 concentration in serum of malignant-tumor patients was up to 90 times higher than in benign ones. The proceeding ratio of CA125 in its productive site (cyst fluid, for example) to that in the serum of patients with malignant lesions was 24 times as high as with benign lesions. No relationship between tumor sizes and the CA125 concentration in serum in nude mice was observed. And in the mice which had high CA125 in serum, the capsules around the tumor tended to be destroyed and vessel infiltration by tumor cells was remarkable.

Animals↗
PubMed1989

[Pharmacokinetic and clinical studies of cefodizime in the field of obstetrics and gynecology].

Cefodizime (THR-221, CDZM), a new antibiotic, was studied pharmacokinetically and clinically. The results obtained are summarized as follows: 1. Concentrations of CDZM in internal genital tissues were quite high after an intravenous infusion. 2. Clinical effects of the therapy with CDZM using intravenous infusion twice daily were evaluated in 1 patient with endometritis, 2 patients with pyometra, 1 patient with extragenital abscess and 1 patient with BARTHOLIN'S gland abscess. Clinical responses were good in all 5 patients. No side effects nor abnormal laboratory test values due to the drug were noted.

Adult↗
PubMed1989

[The study on the human placental L-lactate transport mechanism (using placental microvillous membrane vesicles)].

To elucidate the human placental L-lactate transport mechanism, we investigated L-lactate uptake by microvillous membrane vesicles (MMV) prepared from full termed human placenta using the rapid filtration technique. 1. The transport of L-lactate into the MMV was not dependent on the Na+ electrochemical gradient (extravesicular greater than intravesicular). 2. The transport of L-lactate into the MMV was dependent on the H+ gradient (extravesicular greater than intravesicular) and this H+ dependent L-lactate uptake showed a tendency to overshoot. This overshoot disappeared with the addition of H+ ionophore (FCCP). 3. The initial rate of this H+ dependent L-lactate transport into the MMV exhibited saturation kinetics with respect to the L-lactate concentration: An apparent Km of 4.35mM and Vmax of 2.78n mol/mg protein/20sec were calculated. These results indicated that there existed a H+ and L-lactate transport system in human placental MMV.

Female↗
PubMed1988

LCBF values decline while L lambda values increase during normal human aging measured by stable xenon-enhanced computed tomography.

Results of measurements of LCBF and L lambda values utilizing optimal CT-CBF methods under resting conditions are reported among thirty-two neurologically normal volunteers aged between 20 and 88 years. Measurements were made during inhalation of 26-30% stable xenon gas for 8 min and serial scanning utilizing a state-of the-art CT scanner with both eyes closed and ears unplugged. LCBF values for cortical gray matter were lowest in occipital cortex and highest in frontal cortex. Gray matter flow values were also high in subcortical structures with highest values measured in the thalamus. For white matter, highest flow values were measured in the internal capsule. Changes in LCBF and L lambda values were analyzed with respect to advancing age. Significant age-related declines in LCBF values were observed in occipital cortex and frontal white matter. Significant age-related increases in L lambda values were measured in frontal and temporal cortex, caudate nucleus and thalamus. Possible explanations are offered for these age-related increases in L lambda values for gray matter, such as accumulation of lipofuscin in neurons and relative compacting of gray matter with advancing age. The latter increases the numbers of nerve cells sampled per volume of gray matter measured.

Administration, Inhalation↗
PubMed1988

Interleukin-2 production by human fetal lymphocytes.

IL-2 production by PHA-stimulated human lymphocytes in umbilical blood was studied ontogenetically. Lymphocytes from the 16-week-old fetus produced appreciable amounts of interleukin-2 (IL-2). In 16- to 36-week-old fetuses the IL-2 production rate was found to be significantly higher than that in adults. When signal transduction, which is mediated by high affinity IL-2 receptors (IL-2R), was studied after adding exogenous IL-2 to PHA-blast lymphocytes, the response of the 24-week-old fetus was similar to that of adults. These results indicate that the attainment of IL-2 production and the function of IL-2 receptors are completed at a relatively early stage of fetal development.

Adult↗