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Biomedical subjects

R Iizuka

Publications and source records attributed to R Iizuka.

At least 19 recordsLinked to original sources
PubMed1992

Survey of 1120 Japanese women with a history of recurrent spontaneous abortions.

Our recent 7-year clinical survey showed that among the 1120 women with repeated spontaneous abortions registered in this clinic, 2898 out of a total of 3216 pregnancies (90.1%) had terminated in spontaneous abortion. Among these wastages, 84.2% occurred before 12 weeks of gestation, and 11.1 percent occurred between 12 and 15 weeks. Through routine examination of reproductive wastage, 82 (9.9%) of the 825 Japanese couples examined were shown to have either a chromosomal abnormality or normal variants in the wife and/or husband, thus demonstrating no racial difference in the incidence of chromosomal abnormalities in infertile patients in comparison with studies performed in other countries. One hundred and forty-seven congenital uterine anomalies (14.7%) were found in 1000 hysterosalpingographies, and 12 of 148 examined females were positive for anti-cardiolipin antibody. 393 other females with no major abnormalities likely to induce spontaneous abortions were indicated for immunotherapy. Ample time spent on genetic counseling prevented further reproductive wastage, and ideal metroplasty resulted in a successful post-operative pregnancy course in more than 85% of cases. Immunosuppressant and anticoagulant therapy decreased the serum titer of anti-cardiolipin antibody, enabling pregnancies to be maintained to term. Immunotherapy utilizing the husband's lymphocytes also brought more than 80% of pregnancies to successful completion, with 200 deliveries achieved with this therapy. In contrast, 64.1% of pregnancies again terminated spontaneously in patients who were indicated for immunotherapy but did not receive treatment. The findings of the present study suggest that the causes of reproductive wastage, especially the etiology of early recurrent spontaneous abortion, are complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Habitual↗
PubMed1992

Quick measurement of serum unconjugated estrogens, and its clinical application to abnormal pregnancies and ovarian follicle maturation.

Using an automated HPLC system reported recently by us (J Clin Lab Anal 4:410-413, 1990), serum unconjugated estriol and estradiol (u-E3 and u-E2) can be measured within 22 min. The clinical value of this method was evaluated in this study with abnormal pregnancies, twin pregnancies, and pregnancies associated with fetal anencephaly or complicated by gestational toxicosis or diabetes mellitus. A significant correlation was demonstrated between an abrupt decrease in serum u-E3 level and an abnormal pattern on fetal heart rate monitor. Since urinary E3 was not sensitive enough to detect any depressed fetal condition, serum u-E3 is better biochemical parameter for assessment of fetal well-being. In addition, u-E2 was measured in the sera of nonpregnant women with separation chromatography as a pretreatment in order to obtain higher sensitivity of the system. This modified HPLC system enabled us to determine the serum u-E2 in about 60 min with the minimal detectable value of 80 pg/ml; the coefficient of correlation with RIA was 0.822. As a result, this quick measurement of u-E3 and u-E2 by our HPLC system revealed to be useful not only for evaluating fetoplacental function but also for monitoring ovarian follicle maturation.

Anencephaly↗
PubMed1992

Neurotransmitter changes in early- and late-onset Alzheimer-type dementia.

Neurotransmitter-related markers were examined in Alzheimer-type dementia (ATD) and studied whether or not there is biochemical difference between the early- and late-onset sub-groups. Postmortem brains were obtained from neuropathologically diagnosed ATD patients and control subjects with no clinico-neuropathological findings indicative of neuropsychiatric diseases. Neurochemical data in the early- and late-onset groups were compared to the age-matched younger and older control groups, respectively, and expressed as a percentage of the mean value in the respective controls. Choline acetyltransferase activity and concentrations of serotonin and noradrenaline were more severely depleted in the early-onset ATD group than in the late-onset ATD group. These findings indicative of heterogeneity of ATD patients were discussed from the pathogenetic and therapeutic viewpoints.

Aged↗
PubMed1992

[Loss of catecholaminergic neuron in the hypothalamus of multiple system atrophy].

Autonomic failure is one of the primary clinical features of multiple system atrophy (MSA); while the hypothalamus is thought to be a higher center regulating the autonomic nervous system. In the hypothalamus, catecholamine depletion had been confirmed by neurochemical studies but no marked changes had yet been demonstrated by pathological studies. Using three MSA and three control cases, we evaluated the quantitative changes of catecholamine (CA)-containing neurons in the hypothalamus. As markers of CA neurons, neuromelanin (NM)- and tyrosin hydroxylase (TH)-containing neurons were stained by Fontana-Masson and the immunohistochemical technique alternatively. Serial coronal sections, 10 microns thick, were evaluated every tenth section for NM neurons, while two sections were evaluated for TH neurons. The distributions of NM and TH neurons were almost identical; most of them were clustered in the periventricular and arcuate nuclei. The mean numbers of NM and TH neurons per slice were significantly lower in MSAs than in the controls (T test, p less than 0.01); the former were 21.0, 31.6, and 13.7 in MSAs and 78.4, 54.1, and 84.3 in the controls, while the latter were 1.5, 15.5, and 20.5 in MSAs and 48.0, 62.0, and 50.5 in the controls. The clinico-pathological correlation was suggested by the significant differences in the number of TH neurons between two MSA cases: a case with severe orthostatic hypotension and a case with a milder one. The ratio of TH and NM neurons, as obtained from the adjusted sections, was constant in all MSA cases, and there was a positive statistical correlation, but it altered in each control case.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Loss of dendritic synapses in the medial amygdala associated with kindling.

Kindling stimulation was given in the basolateral amygdala (BLA), the septal area or the corpus callosum in the right hemisphere of adult rats. The density of dendritic synapses was electron microscopically studied in the medial amygdaloid nucleus (MAN) ipsi- and contralateral to the stimulation side. The number of dendritic synapses was markedly decreased in both sides of the MAN of 3 groups of kindled rats. Such reduction occurred in both dendritic shaft and spine synapses. The most remarkable decrease was obtained in the BLA kindling. These results suggest that a decrease of synapses may provide a morphological basis for kindling.

Amygdala↗
PubMed1991

Parvalbumin-immunoreactive neurons in the cortex in Pick's disease.

Parvalbumin (a calcium-binding protein)-immunoreactive (PV-Ir) neurons in the cerebral cortex were examined in 20 postmortem brains obtained from elderly controls and patients with Pick's disease (PD). The type of PV-Ir neurons and their distribution in control and PD brains were similar. The number of PV-Ir neurons in PD brains did not differ significantly from that in the control brains either. These findings suggested that PV-Ir neurons in the cortex are not affected in PD brains. A significant loss of PV-Ir neurons has already been reported in brains obtained from patients with Alzheimer-type dementia (ATD), and the present results suggest the possibility that the damage of PV-Ir neurons might be comparatively selective for ATD brains.

Aged↗
PubMed1991

A study on postmortem stability of vasopressin messenger RNA in rat brain compared with those in total RNA and ribosomal RNA.

Postmortem stability of arginine-vasopressin (AVP) messenger RNA (mRNA) in the rat brain was studied comparing changes with those in the recovered amounts of total RNA and ribosomal RNA (rRNA). The amount of AVP mRNA and rRNA showed a decrease with increasing time interval after death (postmortem time), whereas the amount of total RNA did not alter with postmortem time. The half-life of AVP mRNA in the rat postmortem seemed to be approximately 16 hrs. The analysis of the ratio of AVP mRNA to 18S-rRNA suggested that AVP mRNA was degraded postmortem more rapidly than rRNA. These results suggest that autopsied human brains should be used for AVP mRNA study within a short postmortem time.

Animals↗
PubMed1991

Age- and sex-related differences in the nerve growth factor distribution in the rat brain.

Levels of the nerve growth factor (NGF) have been measured in various brain regions of young and aged male and female rats of Wistar strain by means of a highly sensitive two-site enzyme immunoassay system for beta-NGF. Among the ten regions examined, the amount of NGF per wet weight of tissue was found to be highest in the hippocampus, irrespective of the sex and age. The NGF concentration in the hippocampus of female rats at 3 months of age was comparable to that of same aged males. Further, there was no significant difference in the NGF levels of the hippocampus between young and age males. However, the NGF level was significantly lower in aged females as compared to that in 3- or 4-month-old females, and hence the marked male-female difference was found in the NGF levels in aged Wistar rats.

Aging↗
PubMed1991

A possible mechanism of immunotherapy for patients with recurrent spontaneous abortions.

The mechanism of the beneficial effect of immunotherapy for human reproductive wastage remains to be elucidated. Induction of blocking antibodies such as anti-HLA class II antibodies and anti-idiotypic antibodies was investigated as the mechanism of specific immunosuppression in pregnancy. We reported the changes in the mixed lymphocyte reaction (MLR), T-cell subsets, and generation of anti-idiotypic antibodies after immunotherapy compared to before immunotherapy. MLR was significantly (P less than 0.001) inhibited after the immunization. The mean inhibition rate was 50.2%, suggesting that MLR blocking antibodies were induced by immunotherapy. Binding of autoantibodies to alloactivated maternal lymphoblasts against the paternal lymphocytes was detected in postimmunization cases in two-color flow-cytometric experiments. This suggests that anti-idiotypic antibodies were induced by the immunotherapy. The percentage of cytotoxic T-cells was significantly decreased (P less than 0.05) and the percentage of suppressor T-cells was significantly increased (P less than 0.01) after the immunotherapy, suggesting that a cell-mediated immune response was induced by the immunotherapy.

Abortion, Habitual↗
PubMed1991

Current comprehensive therapy of habitual abortion.

Habitual abortion is sometimes an incurable pathogenetic state. Even more serious to both the patient and gynecologist is that the incidence of repeated reproductive wastage is higher in subsequent pregnancies. We registered more than 1,000 women with repeated spontaneous abortions in this clinic for 5 years and analyzed their pathogenesis for the wastages by several different approaches. One hundred twenty-four women were diagnosed as having a congenital uterine abnormality. Metroplasty was performed in 50 patients, resulting in 82% successful subsequent pregnancies, whereas more than 98% of the pregnancies had terminated in spontaneous abortion before the operation. By measuring anticardiolipin antibody (ACA) and lupus anticoagulant (LA), the present study diagnosed several cases as antiphospholipid syndrome, and successfully pregnant patients were observed and treated with appropriate medications. Fifty-five partners of 54 couples had either a chromosomal abnormality or normal variants, showing a high incidence of spontaneous abortion in each type of abnormality. In the other 311 cases, female partners were treated by the immunotherapy of the husbands' lymphocytes in pre- and postgestational periods. Among them, 200 women became pregnant, and 147 cases successfully maintained the pregnancy. These studies indicate that early diagnosis through comprehensive examinations is essential for effective treatment of curable fetal loss in human reproduction.

Abortion, Habitual↗
PubMed1991

New pathologic observations in juvenile onset parkinsonism with dystonia.

A patient with hereditary juvenile onset parkinsonism with dystonia died at age 39. There were Lewy bodies and regionally selective neuronal damage in the substantia nigra pars compacta. These changes closely resemble those seen in Parkinson's disease, and emphasize the selective vulnerability of the ventral tier of the pars compacta in these degenerations.

Adult↗
PubMed1991

A disorganized increase of galanin-like immunoreactivity in cerebral cortex of Alzheimer-type dementia brains.

Galanin (GAL), a neuropeptide which has been reported to inhibit the evoked release of acetylcholine, is widely distributed in the mammalian central nervous system. In the present study, GAL-like immunoreactivity (LI) was measured in the cerebral cortex of autopsy brains of patients with the Alzheimer-type dementia and controls using an enzyme immunoassay technique. GAL-LI tended to be increased in the ATD brains and the difference was statistically significant in the frontal cortex. Moreover, although significant correlations of GAL-LI between regions of the cerebral cortex were found in the control brains, no such correlations were found in the ATD brains. These findings suggest a disorganized increase in GAL-LI in the cortex of ATD brains.

Alzheimer Disease↗
PubMed1991

[Statistical analysis of possible causes of repeated spontaneous abortions].

The possible causes of early pregnancy failure in one thousand, three hundred and seventeen women (n = 1,317) with a history of repeated reproductive wastage were analysed and the results of treatment for each etiology were evaluated. Out of 1,200 hysterosalpingographies, 188 (15.7%) congenital uterine anomalies were detected and the degree of each uterine cavity deformity was evaluated by the X/M ratio. Metroplasty was performed on 71 women with no other causes of spontaneous abortion, and more than 84% of the post-operative pregnancy were successfully maintained. One hundred and four (n = 104, 5.5%) out of 949 couples with a high incidence of reproductive failure had either a chromosomal abnormality or normal variants in the wife and/or husband. Twelve cases (n = 12, 8.1%) had a positive analysis for anticardiolipin antibody among 148 women examined. Immunotherapy utilizing the husband's lymphocytes was indicated for four hundred and seventy three (n = 473) other couples with no other abnormalities likely to induce spontaneous abortions. This treatment brought approximately 80% of pregnancies to successful termination and 199 deliveries were recorded with this immunotherapy. The present study suggests that the causes of early pregnancy failure are complex, but that most of the causes of repetitive wastage are curable after exact diagnosis and appropriate treatment.

Abortion, Habitual↗
PubMed1991

[Maternal immune responses induced by the immunotherapy in patients with recurrent spontaneous abortions].

The mechanism of the beneficial effect of immunotherapy for human reproductive wastage remains to be elucidated. The induction of blocking antibodies such as anti-HLA class II antibodies and anti-idiotypic antibodies was investigated as the mechanism of specific immunosuppression in pregnancy. We reported that changes in a mixed lymphocyte culture (MLC), T-cell subsets and generation of anti-idiotypic antibodies after immunotherapy compared to before. MLC was significantly (p less than 0.001) inhibited after the immunization. The mean inhibition rate was 50.5%, suggesting that MLR blocking antibodies were induced by immunotherapy. We demonstrated that this blocking effect was specific to the husband, because the inhibition of one-way MLC reactions which were set up with responding maternal lymphocytes and MMC-treated stimulating lymphocytes of third parties were significantly low (p less than 0.05) compared to stimulation with paternal lymphocytes. The binding of autoantibodies to alloactivated maternal lymphoblasts against the paternal lymphocytes was detected in post-immunization cases in two-color flow-cytometric experiments. This strongly suggests that anti-idiotypic antibodies were induced by the immunotherapy. The percentage of cytotoxic T cells was significantly decreased (p less than 0.05) and the percentage of suppressor T cells was significantly increased (p less than 0.01) after the immunotherapy, suggesting that a cell-mediated immune response was induced by the immunotherapy.

Abortion, Habitual↗
PubMed1990

Cell membrane changes in brains manifesting senile plaques: an immunohistochemical study of GM1 membranous ganglioside.

To investigate structural changes in cell membranes of the Alzheimer-type dementia (ATD) brain, we immunostained for GM1 ganglioside which is a major component of the cell membrane. Our results have shown that astrocytic membranes and senile plaques (SPs) have the same immunoreactivity against the monoclonal anti-ganglioside GM1 antibody. Moreover, the astrocytic processes within the SPs were altered and their abnormal membranes seemed to contribute to the formation of SPs.

Aged↗