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Biomedical subjects

Y Takeuchi

Publications and source records attributed to Y Takeuchi.

At least 901 records · Page 50Linked to original sources
PubMed1986

[Bradykinin receptor and the mechanism of the onset of labor].

Bradykinin (BK) receptor of uterus and chorionic membrane were studied by radioreceptor assay to clarify the role of BK as theta an agent contracting uterine muscle. Basic examination revealed that incubation at 0 degrees C for 45 minutes with [3H] BK in buffer containing 5mM Mg++ was the most suitable condition for receptor-BK binding. BK receptor assay of several kinds of tissue such as pregnant rat uterus, human chorionic membrane, and placenta was done and the following results were obtained. Specific BK receptor existed in human chorionic membrane and in rat uterus. Ultracentrifugation revealed that it was on the plasma membrane (145 f mole./mg protein: The highest binding in the pellet at 10,000 g centrifugation followed by 600 g centrifugation). Association constant (Ka) and maximal binding capacity (MBC) showed the lowest level at 15 days gestation in rat uterus. These seemed to effectively maintain pregnancy by inhibiting uterine contraction. Both Ka and MBC were increased in the uterus of intrapartum rat compared with that of prepartum, but the former was about 45%, and the latter was almost the same as, that of non pregnant rat.

Animals↗
PubMed1986

[Study on utero-placental circulation by pulsed-Doppler technique--blood flowmetric study in placental pores].

The flow velocity waveform (FVW) was obtained by means of the pulsed-Doppler technique from the placental pores visualized as anechoic areas on the ultrasonic tomogram in 36 cases of singletons and 7 cases of multiple pregnancies. Utilised parameters for analysis of the sonogram were resistance index and systolic to diastolic ratio of flow velocity (S/D ratio) which were independent of the angle between the ultrasonic beam and the direction of blood flow. Diagnostic apparatus were composed of real-time sector scanner and Doppler unit with FFT analyser by which sampling points were selectable within 15 cm of depth. The FVW from the placental pores was recorded as the toward flow in the case of posteriorly attached placentas and was similar to the one from the arcuate arteries which has poor pulsatility and high diastolic flow in the normal pregnancies. There was a tendency for the increase in the gestosis index (GI) to be related to that of RI. Multiple pregnancies revealed lower RI than singletons in the same GI group. There was reverse correlation between mean birth weight and mean RI in the cases who received pulsed-Doppler examination within 2 weeks prior to delivery. The RI and S/D ratio showed a high correlation in the each cases (r = 0.99).

Adult↗
PubMed1986

Effect of voluntary exercise on resistance to trauma in rats.

To investigate the effect of voluntary exercise on the tolerance to trauma, female rats kept in cages with running wheels for 3-7 weeks (exercise group) were subjected to Noble-Collip drum trauma and compared to rats kept in cages without running wheels for the same period (sedentary group). Both food consumption and weight gain were greater in the exercise group than in the sedentary group. Mortality from the drumming of 600 revolutions was significantly decreased in rats kept in cages with running wheels for 5 weeks or 7 weeks but not in rats kept for only 3 weeks. Mortality from the drumming of 450 revolutions and of 500 revolutions was also significantly lower in the exercising rats. These results indicated that voluntarily exercising rats showed increased resistance to trauma as compared to rats kept under the sedentary condition.

Animals↗
PubMed1986

[Characteristics of heterologous membrane antigen (HM Ag) and humoral immune response to HM Ag in pregnant women and patients with gynecologic malignancies].

Heterologous membrane antigen (HM Ag) is discovered to be incorporated into membranes of cultured human cells grown in media containing fetal calf serum (FCS). To know the characteristics of HM Ag, we investigated the dynamics of HM Ag on cell membrane, distribution of HM Ag and humoral immune response to HM Ag in pregnancy and gynecologic malignancies. The following results were obtained. HM Ag disappeared from the cell membranes of M14 grown in media with fetal calf serum (FCS) after the cells were transferred into whole human serum (12 days) or into a gamma human serum (18 days). M14 cells grown in human serum reincoporated HM Ag into their membranes within 48 hours after transfer to medium with 20% FCS. HM Ag was detected in FCS, adult bovine serum, cow's milk and erythrocytes homogenate of ox and sheep. The natural anti-HM Ag antibody appeared frequently in pregnant women, patients with gynecologic malignancies and healthy persons. These findings suggest that HM Ag must be excluded in immunologic studies of cultured human cancer cells by changing the medium from FCS to human serum or by absorbing anti-HM Ag antibody with cells carrying HM Ag.

Antigens, Surface↗
PubMed1985

[Studies on the thyrotropic activity of hCG and its derivatives].

The placenta may be involved in the regulation of the maternal thyroid function during pregnancy. As human chorionic gonadotropin (hCG) is a primary protein from the placenta, we examined the thyrotropic activity of hCG and its derivatives using tissue culture and monolayer cell culture of human thyroid glands. The TSH receptor preparation was made from thyroid tissues, and its binding affinity with hCG and Asialo hCG (As-hCG) was examined. hCG did not bind to TSH receptor, but As-hCG did. In the experiment with tissue culture, TSH, hCG, hCG alpha, beta subunit and As-hCG were added to the culture medium. Secretions of L-thyroxine (T4) and L-triiodothyronine (T3) in the culture medium were measured at regular time intervals. While TSH showed increases of T4 and T3 secretion, other hCG derivatives did not show any differences from the control values. When TSH and hCG were added together, the secretion of thyroid hormone was the same as that obtained by TSH single administration. On the other hand, the secretion of T4 and T3 was inhibited with co-administration of TSH and As-hCG. Only TSH and none of the other hCG derivatives showed the dose-dependent stimulation of T4 and T3 secretion. A similar experiment was carried out in a monolayer cell culture obtained by trypsin treatment of human thyroid tissue. The secretions of cyclic AMP (c-AMP), T4 and T3 were measured. As in the previous tissue experiment, the thyrotropic activity of TSH was not modified by hCG, but the secretions of T4, T3 and especially c-AMP were inhibited by co-administration of As-hCG and TSH. These findings suggest that hCG and its subunits do not show thyrotropic activity in human thyroid glands, but As-hCG acts as an antagonist of TSH.

Asialoglycoproteins↗
PubMed1985

Direct connections of primary afferent fibers with central cervical nucleus neurons projecting to the cerebellum in the cat.

The synaptic organization of the central cervical nucleus (CCN) in the cat was examined by means of anterograde and retrograde axonal transport of horseradish peroxidase and the anterograde degeneration tracing technique. Light microscopic studies confirmed that cervical primary afferents terminate heavily in the region of CCN cerebellar projection neurons and electron microscopic findings demonstrated that primary afferent fibers of cervical dorsal roots form synapses mainly with distal dendrites of CCN neurons projecting to the cerebellum.

Afferent Pathways↗
PubMed1985

Rimmed vacuoles in biopsied muscle of nemaline myopathy.

A case of nemaline myopathy with rimmed vacuoles was presented. Muscle biopsy revealed type I fiber predominance with type grouping, thus suggesting that neurogenic factors played a pathologic role in the degenerative change.

Biopsy↗