[Fundamental and clinical evaluation of ceftazidime in perinatal studies]

In a chemotherapy of perinatal infections, the safety of mothers and their neonates and the transfer of a drug to amniotic fluid and fetus as well as its bacteriological efficacy are some of the important factors. In the present study, the authors have carried out a pharmacokinetic evaluation on the transfer of ceftazidime (CAZ), a new cephalosporin, to amniotic fluid and umbilical cord serum, and also a clinical study on its efficacy and safety in 3 cases of perinatal infections. Transfer ratios of CAZ to umbilical serum and to amniotic fluid were 25.3-46.5% and 0.6-17.5% (of maternal serum), respectively, after 1 g of CAZ was administered by bolus intravenous injection, and 24.3-85.8% and 1.6-17.5% (of maternal serum), respectively, after 2 g of CAZ was administered by bolus intravenous injection. These levels were high enough to expect that CAZ is an effective antibiotic both for treatment and prophylaxis of intrauterine fetal infections. Out of the 3 cases treated with CAZ, clinical efficacy was good in 2 cases which did not respond to other antibiotics. CAZ was considered to be clinically effective, although the number of cases treated was small. No abnormalities were observed at all either in subjective symptoms or objective findings in laboratory findings such as hepatic and renal functions of mothers, or neonates. This confirmed the high safety of CAZ. As earlier reports indicate, CAZ has a broad-spectrum of antibacterial activity against various bacteria including Gram-negative organisms and anaerobes, and shows a good transfer into intrauterine tissues, and high clinical efficacy in the field of obstetrics and gynecology.(ABSTRACT TRUNCATED AT 250 WORDS)

[The effect of cis-platinum (CDDP) on methotrexate-resistant choriocarcinoma cell line]

Cis-platinum (CDDP) was investigated in vitro and in vivo for its ability to inhibit the growth of Methotrexate (MTX)-resistant choriocarcinoma cell line (BeWo) and was compared with the effect of MTX and Actinomycin D (ACD). Each drug was added into medium (RPMI 1640 containing 10% FBS) for 1 hr. at the concentration of peak plasma level in clinical use (CDDP 7 X 10(-6)M, MTX 10(-6)M, and ACD 8 X 10(-8)M), or for 48 hrs. at one-tenth of the level. CDDP inhibited the cell growth to 40% of control at 7 X 10(-6)M for 1 hr., and 25% at 7 X 10(-7) M for 48 hrs. And ACD suppressed the cell growth to 10% at both 8 X 10(-8)M for 1 hr. and 8 X 10(-9)M for 48 hrs. But MTX did not inhibit the cell growth at 10(-6)M for 1 hr., and inhibited to 60% of control at 10(-7)M for 48 hrs. On the other hand, BeWo transplanted to athymic nude mice (CD-1(ICR) nu/nu) was treated with intraperitoneal injections of CDDP (1.4 mg/kg/day for 4 consecutive days in a week and repeated for 2 and 4 weeks), MTX (2mg/kg/day for 4 consecutive days in a week and repeated for 2 weeks), and ACD (90 micrograms/kg/day for 4 consecutive days in a week and repeated for 2 and 4 weeks). The suppression of the tumor growth was seen in CDDP-treated group (TRW/CRW = 6.5%) and ACD-treated group (TRW/CRW = 29%) after 2 courses of treatment, but no apparent suppression was shown in the MTX-treated group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Chemotherapy of ovarian cancer based on in vitro (HTCA) and in vivo (nude mice) chemosensitivity testing]

The human tumor clonogenic assay (HTCA) and the human tumor xenograft system implanted in nude mice were performed simultaneously in an ovarian cancer patient as chemosensitivity testing. Eight anticancer drugs (5-FU, MMC, VCR, ACD, BLM, VLB, CDDP, and ADM) were applied to the HTCA and the human tumor xenograft system. In the HTCA, 5-FU and MMC were sensitive, VCR was moderately sensitive, and ACD, BLM, VLB, CDDP, and ADM were resistant. In the human tumor xenograft system, MMC, VCR, and ADM showed tumor regression (++), and CDDP, VLB, BLM, 5-FU, and ACD exhibited no response (-). Two of the three drugs, which were classified as sensitive or intermediately sensitive in the HTCA, showed tumor regression (++) in the human tumor xenograft system. And four of the five drugs, which were resistant in the HTCA, exhibited no response (-) in the human tumor xenograft system. Clinically, PVB therapy (CDDP, VLB, and BLM) was applied to the present patient, but after recurrence, 5-FU + MMC therapy was applied on the basis of the results of the HTCA. In addition, ADM was added with reference to the results of the human tumor xenograft system. As a result of this therapy, the tumor growth was inhibited. It is possible from the present data that simultaneous chemosensitivity testing of the HTCA and the human tumor xenograft system implanted in nude mice is very useful when choosing sensitive anticancer drugs.

[Studies on combined effect of hyperthermia and MTX to choriocarcinoma cell line (BeWo)]

Changes in cell growth and hormone production of the choriocarcinoma cell line BeWo were studied to determine the manner in which the change in the cell cycle due to antimetabolite MTX affects heat sensitivity. First of all, BeWo was treated with 10(-7)M-MTX for 48 hrs. on day 4. And heat (43 degrees C for 1 h.) was applied at various stages after MTX removal on day 6. At the same time, the change in the cell cycle induced by MTX was studied by autoradiography. The labeling index (L.I.), which was increasing until 90% by MTX exposure, still remained more than 80% up to 5 hrs. after MTX removal and then decreased to about 43% at 9 hrs. after MTX removal. The greatest effect on cell growth and HCG production was seen when heat was applied within 5 hrs. after MTX removal. And these 5 hrs. corresponded to the time when the L.I. was as high as 80 to 90%. When heat was applied more than 6 hrs. after MTX removal, the heat sensitivity was reduced in proportion to the degree of decrease in the L.I. These findings suggest that the change in the cell cycle induced by MTX has the greatest effect on the heat sensitivity of BeWo. It is therefore possible to conclude that synchronization of BeWo with S phase by using MTX or possibly other antimetabolites is very important in the application of hyperthermia.

[Heat sensitivity of cultured choriocarcinoma cell line (BeWo)]

In order to elucidate the effect of hyperthermia, gestational choriocarcinoma cell line (BeWo) was studied with respect to cell growth and hormone (beta-HCG) production in various conditions of hyperthermia. BeWo was heated in the 39.0-43.0 degrees C temperature range on Day 4. The cell growth was reduced significantly at 43 degrees C for 1 hour. The same effect was observed at 39 degrees C for 120 hours. And this effect was more severe than that at 41 degrees C for 24 hours. BeWo was heated at 43 degrees C on Day 4, Day 5, and Day 6 during the logarithmic growth phase. Maximum suppression of the cell growth was observed on Day 4, and the effect was reduced with the length of time that heat application was delayed. MTX (10(-7)M) was added for 48 hours beginning on Day 4, and heat (43 degrees C for 1 hour) was applied at various points during or after MTX exposure. Heat showed an adjuvant effect with MTX when heat was applied between 24 hours after administration of MTX and 4 hours after removal of MTX. These findings strongly suggest that the heat sensitivity of BeWo is greatly related to the cell cycle. Elevated HCG production was not observed following heat alone, but observed following simultaneous heat and MTX administration. To elucidate the mechanism involved here, further studies will be needed.

[Effect of methotrexate on cell growth and the production of hCG, beta-hCG and SP-1 in cultured choriocarcinoma cell lines]

Three choriocarcinoma cell lines (BeWo, GCH-2 and SCH) cultured in MTX or MTX-free medium were investigated with respect to cell growth and production of hCG, beta-hCG and specific beta-1-glycoprotein (SP-1). MTX was administered at the concentration of 10(-8), 10(-7), 10(-6), 10(-5)M for 24 hours, 72 hours and 168 hours from the fourth day of culture. Each cell line demonstrated that the cell growth and production of hCG and beta-hCG were dose, rather than time, dependent. 10(-6)M or more of MTX had a distinct effect, but 10(-7) or less of MTX had little effect. SP-1 was produced at a low level during culture regardless of the medium used. The ratio of the extra- to the intracellular hCG level was shown to be about 100:1 after the administration of MTX to BeWo and GCH-2. It is, therefore, possible that the temporary elevation of the hCG level observed in vitro after treatment with MTX is the result of an increase in secretion of hCG, rather than cellular damage.

Fetal heart rate accelerations and late decelerations during the course of intrauterine death in chronically catheterized rhesus monkeys

The appearance of late decelerations and the disappearance of accelerations in the fetal heart rate were observed during the days that preceded intrauterine fetal death in nine chronically instrumented rhesus monkeys. All nine animals had recovered satisfactorily from the initial surgical procedure, as evidenced by normal biophysical and biochemical parameters. After recovery, all the fetuses had shown accelerations and no late decelerations with spontaneous uterine contractions. The mean duration of the preparations was 16.1 days. The duration of the preterminal observation period varied from 3 to 13 days, during which time no experiments were performed. The fetuses died during labor at a mean gestational age of 143 days. Late decelerations were the first sign of fetal deterioration and occurred with a slight but significant decrease in fetal PaO2 without changes in pH, whereas accelerations in fetal heart rate were still present. The loss of accelerations in fetal heart rate was a later phenomenon and was associated with significant reductions in fetal pH and PaO2.

Reduction of Noise and Vibrations in a Hydraulic Turbine

This paper describes test procedures and methods used to reduce the abnormal noise and vibrations which had occurred at a hydroelectric station in Japan. Noise level, vibration, and pressure were measured in various operating conditions of two turbines of this station, and the necessary conditions for the noise to grow, the substantial cause and various preventive methods were investigated for a year and a half. Finally the noise and vibrations were eliminated successfully by modification of the runner blading.