Biomedical subjects
Publications and source records attributed to S Sakamoto.
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Quantitative histometry of the placenta seems to make it possible to correlate the histopathological changes with various obstetric complications and disorders more precisely. In the present paper, the relationship between the histopathological changes in the placenta and the obstetric complications was investigated by quantitative histometry based on the standardized categories with uncomplicated normal cases as the controls. Among the obstetric complications, special emphasis has been placed on the pregnancies complicated by toxemia of pregnancy and diabetes mellitus. The obstetric disorders of postmature pregnancy and prolonged delivery have also been related to the quantitative histometry. It was revealed that the cytotrophoblast proliferation associated with the formation of syncytial knots was a very common finding both in toxemia and in these obstetric disorders. However, there was a great difference between the two in that impairment of the vasculature was highly specific in the placentae in the case of toxemia. The most conspicuous histopathological change recognized in the placentae due to diabetes was villous edema, which would be due to the osmotic imbalance. However, it is so unusual to find cases complicated by severe diabetes that typical villous edema is rarely observed. The quantitative approaches in the field of histopathology may leave some problems in that the specimens taken from the organ could not always be representative of the whole organ. However, quantitative histometry based on the fairy standardized categories has been shown to offer more promising information on the relationship between the histopathological changes in the placentae and the obstetric disorders.
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Endometrial cancer is more frequent in patients at a postmenopausal age, when the ovarian secretion of androgens instead of estrogens seems to be relatively increased. In clinical or experimental medicine, progesterones are widely used for the treatment of endometrial cancer, probably because they have an antiestrogenic action and cause differentiation of cancer cells from the proliferative phase. The effects of testosterone(T), progesterone(P), and/or 17 beta-estradiol(E) on the incorporation of 3H-thymidine in autoradiograms were investigated in immature rats. The autoradiogram revealed many grains due to 3H-thymidine in the endometrial epithelium, stroma, and the myometrium in the immature rat 30 hours after E-injection. T alone markedly induced the DNA synthesis in the stroma and the myometrium, but not in the epithelium. T displayed a synergistic interaction with E in both the stroma and the myometrium with a slight increase in thymidine incorporation into the epithelium. P alone induced DNA synthesis in the stroma and the myometrium. Simultaneous injection of E and P also produced the same result as that when P alone was injected. P markedly inhibited DNA synthesis due to E in the epithelium. Autoradiograms of the immature rat uterus provide basic support for the rationality of P therapy for cancer or adenomatous hyperplasia of the endometrium.
Recently, pulsed Doppler echocardiography has been used for the quantitative evaluation of tricuspid regurgitation (TR). However, there are some problems about the clinical significance of TR diagnosed by Doppler examination probably because of the excellent sensitivity in detecting TR. In the present study, we used liver function tests as an indicator of the visceral damage caused by TR and compared them to the severity of TR estimated by Doppler examination. Forty Doppler examinations were performed in 33 cardiac patients including seven, in which the examinations were repeated because the severity of TR changed during the clinical course. The severity of TR was classified into four grades according to the maximal extent of the regurgitant signal. Abnormal liver function was defined by the abnormalities of at least one of the following six tests: cholinesterase (CHE), gamma-GTP, leucine aminopeptidase (LAP), total bilirubin, alkaline phosphatase and GPT. Abnormal liver function tests were present in one of eight patients without TR, two of 10 with 1 + TR, four of seven with 2 + TR, seven of eight with 3 + TR, and six of seven with 4 + TR. The incidence of abnormal liver function tests increased parallel to the grade of TR and was very frequent in patients with 3 + or 4 + TR. TR diagnosed as greater than 3 + by Doppler examination is considered to have an important clinical significance and an indication of the intensive therapy.
A case of atrial septal defect associated with an abnormal chamber behind the right ventricle, which was heretofore undescribed, was reported. A 41-year-old woman was admitted to our hospital for the evaluation of a heart murmur. A Levine 3/6 ejection systolic murmur and a fixed splitting of the second heart sound were audible. Two-dimensional echocardiography disclosed an atrial septal defect and an abnormal chamber behind the right ventricle. This accessory chamber communicating with the right atrium was separated from the right ventricle by a membranous structure. The motion of this membrane showed a wide excursion just like that of the atrio-ventricular valve. On the M-mode echocardiogram, the anterior tricuspid leaflet and this membrane were recorded simultaneously without intervening septal echoes and this finding was very similar to that obtained in the single ventricle. Cardiac catheterization revealed that the pressure pattern in the abnormal chamber was that of the right atrium but its intracardiac electrocardiogram showed a right ventricular pattern. The complex morphological aspect of this case was confirmed by angiography and surgery. The developmental process of this very unusual anomaly is not clear, but it may be a kind of congenital anomaly related to Ebstein's anomaly.
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Three cases of verrucous carcinoma arising at the uterine cervix were presented with regard to their clinical courses, histological and ultrastructural findings, referring specially to the problems of diagnosis and treatment, and the relationship between viral infection and the disease. In order to obtain a correct diagnosis of verrucous carcinoma, not only repeated punch biopsies, but also wide resection of the tumor by incision biopsy are indispensable, aiming at an accordance between clinical and pathological diagnosis. In treating verrucous carcinoma, which is a slowly progressive nonmetastasizing tumor with strong local invasion, surgery should be the primary choice. Radiotherapy including postoperative irradiation is contraindicated for the reason that not only is verrucous carcinoma radioresistant, but also because anaplastic change following radiation often occurs. Even though in our survey using electronmicroscopy, no virus-like particles were observed, there still remains a strong possibility of the participation of some infections in verrucous carcinoma. This is because all of the primary lesions in our cases, like the other reports in the literature, were located at the posterior lip of the portio .
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Five patients with multiple myeloma were treated with human lymphoblastoid interferon (HLBI). HLBI, 3 X 10(6) IU/day, was administered daily for more than two weeks by intramuscular injection. Out of four evaluable patients, a minor response was obtained in 3 patients. In these responders, one patient developed pleural effusion due to the infiltration of myeloma cells during the administration of HLBI, and drug resistance was observed in another patient during the re-administration of HLBI. Therefore, out of six evaluable courses, a minor response was obtained in 3 courses of HLBI treatment. No severe side effects were observed. Thrombocytopenia, general malaise, liver dysfunction and anorexia were the main reasons for discontinuation of HLBI administration. On the basis of the preliminary study, it is concluded that HLBI is worth trying in the management of refractory multiple myeloma.
The human amnion has become a significant tissue for metabolism of chemical substances with biologic activities, such as steroid hormones and prostaglandins. In this paper our studies on the biosynthesis of prostaglandins in human amnion focused on the role of prostaglandins in initiating and maintaining labor. First of all, the source of prostaglandins released in amniotic fluid was investigated. The amnion was demonstrated to possess the highest activity of generating prostaglandins among amnion, chorion laeve, and decidua vera, obtained after normal vaginal delivery. Subsequently, the bioconversion of arachidonic acid into prostaglandins and related compounds using the homogenate of human amnion was carried out without the addition of cofactors in the incubation mixture to show the natural spectrum of various types of PGs formed. PGE2 was revealed to be a main product of the amnion; its conversion rate was 5% of incubated radioactivity. Other compounds catalyzed by cyclooxygenase were PGF2 alpha (0.2%), TXB2 (0.3%), and HHT (1-2%), whereas 15-HETE (2-3%) and a mixture of 9, 11, 12-HETE (1-2%) were formed by lipoxygenase in the amnion. And third, the activity to produce PGE2 in the amnion obtained at normal vaginal delivery was greater than that obtained at cesarean section prior to the onset of labor. Thus, these results suggested that the amnion played a significant role in prostaglandin biosynthesis in uterine tissues. To provide a better understanding of the metabolism of arachidonic acid in the amnion as regards initiation and maintenance of labor, we discuss prostaglandin biosynthesis in the amnion and the mechanism of arachidonic acid release.
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11-Deoxycortisol was assayed in maternal and cord plasma. The concentrations in maternal plasma increased as pregnancy progressed and reached a peak at 39 weeks. The levels decreased very rapidly in the postpartum period. In cases of intrauterine fetal death and anencephalic fetuses, the values were apparently lower than normal. In women who had undergone bilateral adrenalectomy, the maternal plasma levels were almost normal. The maternal levels were high in cases of twin pregnancies. Therefore, it is assumed that the fetus or the fetoplacental unit is the source of the increased 11-deoxycortisol in maternal plasma during late pregnancy.
In previous experiments it was found that PGF2 alpha originating from the uterine endometrium plays a physiologically important role in corpus luteum regression. The present study was undertaken to investigate the regulation of PGF2 alpha release from the uterus in luteolysis. The effect of ovariectomy on PGF2 alpha release was examined. Bilateral ovariectomy was performed on day 14 of pseudopregnancy. PGF2 alpha urinary metabolite excretion was almost constant from day 15 to 22, although a significant increase of PGF2 alpha UM excretion could be seen in the control rabbits. Ovariectomy was performed on day 17. Levels of PGF2 alpha UM excretion increased from day 15 to 17, however, an abrupt decrease occurred after ovariectomy. This indicates that the ovaries are necessary for PGF2 alpha release from the uterus. The effect of steroids on PGF2 alpha release was examined. No significant increase in PGF2 alpha UM excretion could be seen in the ovariectomized pseudopregnant rabbits by the administration of estradiol and/or progesterone, although they are reported to be involved in other species. The effect of the ligation of the vessels between the uterus and ovaries on PGF2 alpha release was investigated. The ligation was performed on day 9. No increase in the production of PGF2 alpha occurred after ligation. Luteal life span was prolonged by 6 days. Endometrial perifusion was carried out to investigate PGF2 alpha production activity on day 18 of the pseudo-pregnant rabbits after the ligation of the vessels between the uterus and ovaries. PGF2 alpha production activity in the treated rabbits was lower than in the controls. These results indicate that a non-steroidal regulator may regulate PGF2 alpha release via the circulation of the uterus and ovaries in the pseudopregnant rabbit.
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