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Biomedical subjects

I Taniguchi

Publications and source records attributed to I Taniguchi.

At least 73 records · Page 4Linked to original sources
PubMed1990

Enzyme immunosensors based on electropolymerized polytyramine modified electrodes.

Highly sensitive amperometric enzyme immunosensors for human immunoglobulin G (IgG) were prepared on the basis of electrogenerated polytyramine (PTy, tyramine = p-(2-aminoethyl)-phenol) modified electrodes. Properties of PTy films changed depending on electrolysis conditions. On the basis of the found properties of the films, an effective IgG sensor was prepared: a PTy film was formed first from an acid solution on a Pt electrode, and the surface was further covered with a PTy film from an alkaline methanol solution to give a PTy doubly coated electrode on which anti-IgG was then immobilized. This electrode provided a large surface area with little non-specific adsorption of proteins. By means of the competitive enzyme immunoassay technique using glucose oxidase (GOD) labeled IgG conjugates, IgG was determined in the concentration range of c. 10 pg/ml-1 mg/ml from the oxidation current of H2O2 generated by the enzyme (GOD) reaction using the above IgG sensor. Also, an anti-IgG immobilized electrode, prepared by using a Pt electrode singly covered with a PTy film from an alkaline methanol solution, acted as an effective IgG sensor with a detection limit for IgG of c. 100 pg/ml.

Antibodies, Anti-Idiotypic↗
PubMed1990

Hormonal and clinical effects of multifollicular puncture and resection on the ovaries of polycystic ovary syndrome.

Sixteen women with polycystic ovary syndrome (PCOS) were treated with laparoscopic multifollicular puncture and resection (MPR), an original technique which we substitute for ovarian wedge resection. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T), estrone (E1), estradiol (E2), androstenedione (A) and dehydroepiandrosterone sulphate (DHEAS) were measured daily before and after the operation. Clinically, 15 of the 16 patients (93.8%) exhibited spontaneous ovulation and pregnancies occurred in 8 patients (50%). Significant hormonal changes were observed in serum T. Serum T levels dropped in response to the treatment and remained low for 5 days. Serum E1, A, DHEAS and LH levels were elevated before treatment and did not change after the operation. Serum E2 and FSH levels were within the normal range before the treatment and did not change after the operation. We conclude that surgical treatment for PCOS patients should consist of laparoscopic MPR.

Androstenedione↗
PubMed1990

[Right ventricular dysfunction of mitral valve stenosis].

Right ventricular function was studied in 9 patients with mitral valve stenosis who underwent mitral valve replacement (St. Jude Medical valve 29-31 mm) (MVR). The right ventricular systolic pressure/end-systolic volume index (RVSP/ESVI) correlated well with right ventricular ejection fraction (RVEF) in the normal control group thus it considered to be a index of right ventricular contractility. At rest, RVEF in the MVR group was significantly lower than that in the control group. However there was no difference in the RVSP/ESVI between both groups. In the MVR group, the total pulmonary resistance index (TPRI) and mean pulmonary arterial pressure (mPAP) were higher than those in the control group. During exercise, the RVSP/ESVI became higher in both groups, but RVEF did not increase in the MVR group. In the control group, RVEF became higher during exercise. In addition, TPRI and mPAP increased in the MVR group but the control group did not show significant changes during exercise. In conclusion, low RVEF after MVR, which reflects pump function of the right ventricle, was not caused by contractile dysfunction of the right ventricle but mainly by excess afterload due to irreversible pulmonary vascular resistance persisting after operation as a result of chronic pulmonary vascular hypertension.

Adult↗
PubMed1989

Correlation between the size of song control nuclei and plumage color change in orange bishop birds.

Adult male orange bishop birds (Euplectes franciscanus) develop beautiful nuptial plumage during the breeding season, but have the same sober plumage as the female during the non-breeding season. The male conspecific song is highly stereotyped during nuptial plumage. Large volume differences were found in two song control nuclei in the cerebrum between the male and female during the breeding season, and in the same nuclei of the males during the breeding and non-breeding seasons. The seasonal changes in the size of cerebral song control nuclei were dominant in the male and may not correlate with the improvement or modification of the song repertories.

Animals↗
PubMed1988

Functional laminar and columnar organization of the auditory centers in echolocating Japanese greater horseshoe bats.

During echolocation, bats coordinately employ the vocalization system to emit orientation sounds and the auditory system to hear returning echoes. The brain in these animals should be functionally organized to process such biologically significant sounds. Here we utilized the autoradiographic 2-deoxy-[14C]glucose (DG) method to visualize functional organization of the auditory centers of echolocating Japanese greater horseshoe bats, Rhinolophus ferrumequinum nippon. Autoradiographic color images made from the brains of echolocating bats revealed a functional laminar structure in the inferior colliculus. Furthermore, a functional columnar organization appeared in the auditory cortex during echolocation. These laminar and columnar organization were not observed in the brain of resting bats.

Acoustic Stimulation↗
PubMed1988

Abnormal polyamine metabolism in hypertensive cardiac hypertrophy.

In order to assess myocardial hypertrophic activity during the process of hypertensive cardiac hypertrophy in the presence and absence of treatment with anti-hypertensive agents, we analyzed myocardial polyamine concentrations in spontaneous hypertensive (SHR) rats and control rats of Wistar Kyoto (WKY) strain. The anti-hypertensive agents studied were diltiazem, hydralazine and captopril, each of which was administered for 5 weeks. In comparison with WKY rats, SHR rats showed elevated blood pressure and enlarged hearts with higher myocardial spermidine concentration. Although blood pressure was lowered in the diltiazem-treated SHR rats, heart weight and myocardial spermidine concentration increased as in untreated SHR rats. In the hydralazine-treated group increases in both blood pressure and myocardial spermidine concentration were suppressed, while an increase in heart weight was not. In the captopril-treated group, increases in blood pressure, heart weight and spermidine concentration were all suppressed. Since spermidine level appears to be a sensitive indicator of hypertrophic activity in the heart, this study suggests that captopril exerts an inhibitory effect on hypertensive cardiac hypertrophy whereas diltiazem does not. It also suggests that hypertrophy may reach a certain plateau level earlier in the hydralazine-treated animals than in others.

Animals↗
PubMed1987

The personalized auditory cortex of the mustached bat: adaptation for echolocation.

1. In the mustached bat, Pteronotus parnellii, the "resting" frequency of the constant-frequency component of the second harmonic (CF2) of the orientation sound (biosonar signal) is different among individuals within a range from 59.69 to 63.33 kHz. The standard deviation of CF2 resting frequency is 0.091 kHz on the average for individual bats. The male's CF2 resting frequency (61.250 +/- 0.534 kHz, n = 58) is 1.040 kHz lower than the female's (62.290 +/- 0.539 kHz, n = 58) on the average. Females' resting frequencies measured in December are not different from those measured in April when almost all of them are pregnant. Therefore, the orientation sound is sexually dimorphic. 2. In the DSCF (Doppler-shifted CF processing) area of the auditory cortex, tonotopic representation differs among individual bats. The higher the CF2 resting frequency of the bat's own sound, the higher the frequencies represented in the DSCF area of that bat. There is a unique match between the tonotopic representation and the CF2 resting frequency. This match indicates that the auditory cortex is "personalized" for echolocation and that the CF2 resting frequency is like a signature of the orientation sound. 3. If a bat's resting frequency is normalized to 61.00 kHz, the DSCF area overrepresents 60.6-62.3 kHz. The central region of this overrepresented band is 61.1-61.2 kHz. This focal band matches the "reference" frequency to which the CF2 frequency of a Doppler-shifted echo is stabilized by Doppler-shift compensation. 4. Since DSCF neurons are extraordinarily sharply tuned in frequency, the personalization of the auditory cortex or system is not only suited for the detection of wing beats of insects, but also for the reduction of the masking effect on echolocation of consepecific's biosonar signals. 5. Because the orientation sound is sexually dimorphic and the auditory cortex is personalized, the tonotopic representation of the auditory cortex is also sexually dimorphic.

Acoustic Stimulation↗
PubMed1986

Response properties of FM-FM combination-sensitive neurons in the auditory cortex of the mustached bat.

For echolocation, the mustached bat, Pteronotus parnellii rubiginosus, emits orientation sounds (pulses) and listens to echoes. Each pulse is made up of 8 components, of which 4 are constant frequencies (Cf 1.4) and 4 are frequency-modulated (FM 1-4). Target-range information, conveyed by the time delay of the echo FM from the pulse FM, is processed in this species by specialized neurons in a part of the auditory cortex known as the FM-FM area. These cortical neurons are responsive to pulse-echo pairs at specific echo delays. The essential components in the sound pair include the pulse FM1 followed by an echo FMn (n = 2, 3 or 4). Downward sweeping FM1-FMn sounds that are similar to those the animal naturally hears during echolocation are the most effective in evoking facilitative responses. Most FM-FM neurons, however, still exhibit facilitative responses to stimulus pairs consisting of upward sweeping FM sounds and/or pure tones at frequencies found in FM sweeps. The magnitude of facilitation is altered by changes in echo rather than pulse amplitude. Neurons characterized by shorter best delays (or echoes from closer targets) do not require larger best echo amplitudes for facilitation.

Animals↗
PubMed1985

Cardiorespiratory arrest in a patient with advanced diabetic autonomic neuropathy.

A 53-year-old diabetic woman who had been diabetic for 14 years had recurrent episodes of cardiorespiratory arrest, which were easily resuscitated by a few chest massages. In 2 of 4 episodes a radial pulse was detected, so respiratory arrest was thought to be a primary event. Pentazocine was injected several hours prior to each of the 3 episodes. This was considered to be a precipitating factor. From the first episode of cardiorespiratory arrest, she received oxygen inhalation. When oxygen inhalation was withdrawn for 5-10 min, she became cyanotic. This was considered to be a sign of lack of hypoxic drive mediated by peripheral chemoreceptors. Ventilatory responses to hypercapnia was markedly decreased, indicating impaired central chemosensitivity. The possibility that impaired chemosensitivity could be a cause of respiratory arrest was suggested.

Autonomic Nervous System Diseases↗
PubMed1985

Erythrocyte filterability and adenosine triphosphate levels in normal pregnancy and puerperium.

The filterability of erythrocytes was determined by a filtration method using erythrocytes suspended either in phosphate-buffered saline or in native plasma. Erythrocytes from pregnant women in the second and third trimester were significantly less filterable than those from non-pregnant women. On 0 to 1 day after delivery, erythrocyte filterability was further reduced, being significantly lower than that in the third trimester of pregnancy. Erythrocyte adenosine triphosphate (ATP) levels during pregnancy were not significantly different but in early puerperal period it was significantly lower than that in non-pregnant women. One month after delivery the filterability and ATP content of erythrocytes returned to the non-pregnant levels. The size and hemoglobin concentration of erythrocytes were unchanged during pregnancy and puerperium.

Adenosine Triphosphate↗
PubMed1984

[Erythrocyte deformability and adenosine triphosphate (ATP) levels in normal pregnancy and puerperium].

Erythrocyte deformability and erythrocyte adenosine triphosphate (ATP) levels were measured in normal pregnancy and puerperium. Erythrocyte deformability was determined by measuring filtered volumes of red cell-plasma or buffer suspension per second. Erythrocytes from pregnant women at 16-27 weeks, 28-31 weeks and 36-41 weeks of gestation were found to be significantly less deformable than erythrocytes from non pregnant women. On 0-1 day after delivery, erythrocyte deformability was significantly reduced, compared with that at 36-41 weeks of gestation. Erythrocyte ATP levels at 16-27 weeks, 28-31 weeks and 36-41 weeks of gestation were significantly lower than that in non pregnant women. In puerperium, erythrocyte ATP levels dropped significantly compared with those in late gestational period. From these results, it was suggested that the depressed erythrocyte deformabilities were accompanied by a lowering of erythrocyte ATP levels in pregnancy and puerperium.

Adenosine Triphosphate↗
PubMed1983

A critical level of diabetic autonomic neuropathy.

Diabetic autonomic neuropathy was expressed quantitatively using the coefficient of variation of R-R intervals (CVR-R) in ECG and its critical level where diabetics were plagued with various symptoms was investigated. The subjects were 58 diabetics under the age of 40 years. ECGs were recorded in the resting supine position and the degree of autonomic neuropathy was expressed as CVR-R by processing 100 consecutive R-R intervals. Symptoms caused by diabetic autonomic neuropathy were determined using a questionnaire. CVR-R were 1.10 +/- 0.34% (mean +/- SD) and 4.31 +/- 2.01% in patients with and without orthostatic hypotension respectively, the former being significantly lower. CVR-R were 1.30 +/- 0.88% and 3.81 +/- 1.31% in those with and without impotence respectively, the former being significantly lower. CVR-R were 0.80 +/- 0.14% and 3.85 +/- 2.17% in those with and without diabetic diarrhea respectively, the former being significantly lower. Concerning sweating abnormality CVR-R were significantly reduced in subjects exhibiting gustatory sweating (1.52 +/- 0.74%) and hypohidrosis (2.26 +/- 1.44%) when compared to those without these symptoms. From the results obtained, a CVR-R of 2% can be considered as the critical level which determines whether symptoms due to diabetic autonomic neuropathy will appear or not.

Adolescent↗
PubMed1983

[Effect of gestational diabetes on erythrocyte aggregation].

In order to elucidate the tendency to erythrocyte aggregation in gestational diabetes, blood viscosity at a standard hematocrit of 45% (corrected viscosity) was measured at low shear rates in the third trimester of normal pregnancy and pregnancy with gestational diabetes. The mean values (+/- S.D.) for corrected viscosity of 20 gestational diabetic patients were 69.2 +/- 16.6cp at shear rate of 0.11 sec-1, 34.9 +/- 5.3cp at 0.54sec-1 and 27.9 +/- 5.0cp at 0.99sec-1. They were significantly higher than those of 40 normal pregnant patients (55.2 +/- 11.4cp at 0.11sec-1, 29.0 +/- 2.6cp at 0.54sec-1 and 24.4 +/- 2.4cp at 0.99sec-1). The mean value of fibrinogen of gestational diabetic patients was 408.8 +/- 106.7 mg/dl and significantly higher than that of normal patients (313.3 +/- 65.1 mg/dl). The increased tendency to erythrocyte aggregation observed in the diabetic patients was due to increased fibrinogen and would induce microcirculatory disturbance and mild hypoxia in the placental tissue. The cytotrophoblastic cell proliferation which is a characteristic morphological finding of diabetic placenta would be induced as a result of the reaction of placental tissue to the hypoxia thus produced.

Alpha-Globulins↗
PubMed1982

[Management of fetuses in the late pregnancy by serial determinations of serum human placental lactogen levels].

Serum human placental lactogen levels (HPL) were measured serially during the last three weeks before full term deliveries of 69 normal and 60 high risk pregnant women with the method of latex agglutination (Gestefollow 'Eiken'). Except pregnancies complicated with diabetes mellitus, no fetal distress were observed when deliveries were made while HPL levels were increasing. The incidence of fetal distress was only 3.7 per cent when the range of variation of HPL levels was within 20 per cent for 3 weeks before delivery. On the contrary, the incidence of fetal distress increased to 29.4 per cent when infants were delivered after decreasing of HPL levels to less than 80 per cent of the highest HPL levels. It was also demonstrated that single determinations of HPL levels were not clinically useful in predicting fetal distress or fetal growth retardation.

Female↗
PubMed1982

[Endometrial cytology by endocyte and by Masubuchi's aspiration technic --a comparative study--].

Lately there is a tendency for an increase in the incidence of endometrial cancer both in this country and other industrialized countries such as the United States. The routine cervicovaginal smear method is generally poor for the detection of endometrial carcinoma as compared to that used for the diagnosis of early cervical neoplasms. The principal reason for the poor detection rate is that the cells are not obtained directly from the lesion as is the case with disease of the cervix. Various techniques for obtaining endometrial cells directly from the lesions have been described, but none has enjoyed wide acceptance by the clinicians. The patients for this study consisted of 138 women who were referred to us for diagnostic curettage. We employed the new disposable device, the Endocyte, and Masubuchi's endometrial aspiration and compared the results. After obtaining specimens with both methods curettage was performed on all patients. In addition, the Endocyte was employed on 8 patients with endometrial carcinoma in another hospital, and the following results were obtained. 1. With the Endocyte it is possible to obtain a larger volume of cells than by aspiration. 2. Although a certain amount of difficulty is encountered in the insertion of the Endocyte in some cases, it is much easier than the brush method used heretofore. 3. No significant difference in the amount of bleeding after insertion could be observed between the two methods. 4. In patients with bleeding in the endometrium and pyometra it is easier to obtain specimens from the endometrium with the Endocyte than by aspiration. 5. With the Endocyte contamination of the cells of the cervix was less than after aspiration. 6. Although pain during collection of cells with the Endocyte was somewhat stronger than during aspiration, analgesics were not necessary in any one of the cases. 7. The Endocyte was used on 13 patients with endometrial carcinoma, and all specimens were positive for carcinoma. From the results of our study we conclude that for endometrial cytology the Endocyte is as useful as the aspiration method. Furthermore, it should pose no difficulty to the gynecologists to use the Endocyte because the Endocyte resembles IUD structurally.

Adult↗