Levels of hepatocyte growth factor and its messenger ribonucleic acid in uncomplicated pregnancies and those complicated by preeclampsia.

The purpose of this study was to elucidate the possible relationship between hepatocyte growth factor (HGF) expression and the pathogenesis of preeclampsia. The concentration of immunoreactive HGF was measured and the expression of HGF messenger ribonucleic acid (mRNA) assessed in human placentas obtained from two groups: uncomplicated and preeclamptic pregnancies at various gestational weeks. In addition, the localization of HGF mRNA and c-met protein was analyzed using in situ hybridization and immunohistochemical staining, respectively. The expression of HGF mRNA and the concentration of immunoreactive HGF were highest in second trimester and were significantly decreased in preeclamptic placentas compared with the uncomplicated cases in third trimester. HGF mRNA was localized to placental mesenchymal cells, whereas c-met protein was demonstrated on cytotrophoblast. These results provide evidence of an abnormality of HGF expression in the preeclamptic placentas. Such placentas exhibit the abnormally shallow trophoblast invasion of the uterus, and reduced expression of HGF could well account for this morphometric change.

The study of mitochondrial gene modifications in human placenta.

A quantitative study on the effects of placental senescence on mitochondrial DNA (mtDNA) was carried out by measuring mitochondrial gene mutation, levels of mRNA for the cytochrome c oxidase subunit I (COI) and of mtDNA in normal placental tissues at different stages. Deleted mtDNA, the expression of COI in mitochondria and the amounts of mtDNA per cell were examined by the polymerase chain reaction, northern blot analysis and southern blot analysis, respectively. No accumulation of mutant mtDNA with a 4977 base pair (bp) deletion was detected in the normal placenta during pregnancy. There appeared to be a gradual increase of COI mRNA as pregnancy progressed, while the ratio of mtDNA to total DNA in human placenta tended to decrease with gestation. These results indicate that placental ageing is not associated with the accumulation of mtDNA mutation with the 4977 bp deletion or markedly reduced expression of the mitochondrial genome.

Autocrine mechanism of epidermal growth factor in choriocarcinoma cell proliferation.

We examined four choriocarcinoma cell lines, NaUCC-1, NaUCC-3, NaUCC-4 and BeWo, for the presence of epidermal growth factor (EGF) by enzyme immunoassay and reverse transcription and polymerase chain reaction, and for EGF receptor (EGFR) by 125I-EGF binding assay. Specific EGF binding and EGF proteins were detected in these four choriocarcinoma cell lines. On the cell lines examined, NaUCC-4 had the greatest EGF binding capacity (18 x 10(5) sites/cell) and the highest amount of immunoreactive EGF (142 pg/ml). These results prompted us to assess the significance of EGF/EGFR autocrine mechanism in NaUCC-4 cells. Low doses of exogenous EGF stimulated 3H-thymidine incorporation, and monoclonal antibodies against EGF or EGFR dose-dependently inhibited 3H-thymidine incorporation. On the other hand, these antibodies did not significantly affect hCG production. These results suggested that EGF might function in an autocrine manner to stimulate proliferation rather than differentiation of NaUCC-4 choriocarcinoma cells.

Effect of interleukin 2 on the production of progesterone and prostaglandin E2 in human fetal membranes and its consequences for preterm uterine contractions.

Our objective was to clarify the mechanism of uterine contraction induced in pregnant women by intrauterine bacterial infection. The concentration of interleukin 2 (IL-2) was measured in amniotic fluids that had been obtained by amniocentesis, transvaginal amniotomy or by transuterine amniocentesis performed at cesarean section in 50 pregnant women. The concentration of IL-2 in those cases with intrauterine infection was significantly higher than that of those without intrauterine infection at preterm. The same tendency was found at term. Scatchard analysis demonstrated the presence of an IL-2 receptor in the fetal membranes. We collected the fetal membranes aseptically for the measurement of progesterone and prostaglandin E2 by radioimmunoassay following incubation with various concentrations of interleukin 1 (IL-1) and IL-2 at 37 degrees C for 16 h. The production of progesterone was inhibited significantly by 10 pmol/l IL-2 but not by 10 pmol/l IL-1. The production of prostaglandin E2 was accelerated significantly by either IL-1 or IL-2 at a dose of 10 pmol/l. The inhibitory effect of IL-2 on the production of progesterone was unaffected by indomethacin, which inhibits the production of arachidonate cycloxygenase metabolites such as prostaglandin E2. Our present data suggest that the presence of intrauterine bacterial infection may stimulate the intrauterine production of IL-2, and that the stimulation of IL-2 and the reduction of progesterone caused by IL-2 may in part explain the mechanism of uterine contraction associated with intrauterine infection during pregnancy.

Longitudinal monitoring of fetal behavior in twins when one is anencephalic.

BACKGROUND: To our knowledge, there has been no report on longitudinal monitoring of fetal behavior in the anencephalic fetus. CASE: A 30-year-old woman was diagnosed with a twin pregnancy at 8 weeks' gestation; at week 20, one of the twins was identified as anencephalic. From 25-36 weeks' gestation, the behavioral patterns of each fetus were recorded weekly on videotape for 60 minutes, then compared with morphologic findings after birth. CONCLUSION: Our data comparing normal and anencephalic fetuses indicate that the development of the central nervous system above the medulla oblongata plays an important role in the elimination of fetal movements, such as startle, jumping, and writhing, and in the commencement of breathing movements.

Human amniotic fluid motogenic activity for fetal alveolar type II cells by way of hepatocyte growth factor.

OBJECTIVE: To find out if hepatocyte growth factor (HGF) in amniotic fluid (HGF-AF) has a direct effect on fetal lung development, we investigated the effects of AF as well as recombinant human HGF (rhHGF) on proliferation, migration, and morphogenesis of fetal alveolar type II cells in vitro. METHODS: Amniotic fluid samples were obtained from 37 women at various gestational ages. Mitogenic, motogenic, and morphogenic activity was investigated by 5-bromo-2'-deoxyuridine incorporation, Boyden chamber assay, and culture in collagen-gels, respectively. RESULTS: The motility of AK-D cells was stimulated by AF from 14 to 31 weeks' gestation in proportion to the concentration of HGF-AF, and this effect was comparable to that observed with rhHGF. Furthermore, this activity was neutralized by anti-human HGF antibody. However, AF samples subsequent to 32 weeks had no motogenic influence despite the continued presence of immunoreactive HGF-AF. Neither increased DNA synthesis nor morphogenesis in response to AF was identified under the conditions used. CONCLUSION: The present study suggests that AF stimulates alveolar type II cell migration by way of HGF-AF in vitro.

Expression of angiotensin-converting enzyme in human placenta and its physiologic role in the fetal circulation.

OBJECTIVE: To clarify the physiologic function of angiotensin-converting enzyme (EC 3.4.15.1) in the human placenta. METHODS: The concentrations of angiotensin I and angiotensin II were measured in the umbilical artery and vein. In addition, the expression of angiotensin-converting enzyme messenger RNA (mRNA) and its activity in the human placenta were studied. The amount of angiotensin-converting enzyme mRNA was measured by Northern blot hybridization with specific human complementary DNA. RESULTS: The mean (+/- standard deviation) level of angiotensin I was significantly higher in the umbilical artery than in the umbilical vein (1044.5 +/- 626.5 versus 796.5 +/- 372.8 pg/mL; P < .05). In contrast, the mean level of angiotensin II was significantly lower in the umbilical artery than in the umbilical vein (97.3 +/- 102.9 versus 129.3 +/- 110.3 pg/mL; P < .05). Angiotensin-converting enzyme mRNA was detected in the human placenta at 4.5 and 3.9 kilobases. The amount of angiotensin-converting enzyme mRNA increased over the course of pregnancy but decreased near term, whereas angiotensin-converting enzyme activity in the human placenta continued to increase from the first trimester to term. CONCLUSION: The placenta appears to contribute to the conversion of angiotensin I to angiotensin II in the fetal circulation.

Decrease in cytochrome c oxidase and cytochrome oxidase subunit I messenger RNA levels in preeclamptic pregnancies.

OBJECTIVE: To elucidate the possible relation between mitochondrial gene expression and placental dysfunction. METHODS: We measured the activity of cytochrome c oxidase and the expression of cytochrome oxidase subunit I in mitochondria from human placentas of women whose gestations were appropriate for gestational age (AGA) and those with preeclampsia. In addition, the amounts of normal mtDNA and deleted mitochondrial DNA were examined in the two groups by Southern blot analysis and polymerase chain reaction, respectively. RESULTS: Cytochrome c oxidase activity and expression of cytochrome oxidase subunit I were significantly lower in the preeclamptic group than in the AGA group. There were no differences between the groups in the amounts of mitochondrial DNA. In addition, no mutant mitochondrial DNA with a 4977-base pair deletion was detected in the two groups. CONCLUSION: These results suggest that reduced expression of the mitochondrial gene is involved in placental dysfunction in preeclamptic pregnancy.

Umbilical plasma concentration of endothelin-1 in intrapartum fetal stress: effect of fetal heart rate abnormalities.

OBJECTIVE: To measure the umbilical plasma concentration of endothelin (ET)-1 in the presence of labor, fetal heart rate (FHR) abnormalities, and fetal hypoxia. METHODS: Umbilical and maternal plasma concentrations of ET-1 were measured in 100 pregnant women at full-term deliveries (60 with vaginal delivery without induction and 40 with elective cesarean delivery without labor). We assessed the FHR pattern, measured umbilical blood gases and plasma concentration of vasopressin, and investigated the relationships between the umbilical vein-artery ET-1 concentration difference and these variables. RESULTS: The concentration of ET-1 in the umbilical vein was higher than in the umbilical artery and the maternal vein in all cases. The umbilical vein-artery ET-1 concentration difference (mean +/- standard error of the mean) was significantly greater in the vaginal delivery group (4.5 +/- 2.0 pmol/L) than in those delivered by elective cesarean (1.7 +/- 1.5 pmol/L) (P < .05). The umbilical vein-artery ET-1 concentration difference was significantly greater when more than three episodes of severe variable decelerations occurred during the 30-minute period before delivery (7.0 +/- 2.0 pmol/L) than in the absence of any decelerations (1.6 +/- 1.5 pmol/L) (P < .05). The umbilical vein-artery ET-1 concentration difference correlated positively with the umbilical arterial concentration of vasopressin (r = 0.45, P < .05) and negatively with the umbilical arterial oxygen pressure (r = -0.47, P < .05). CONCLUSION: In cases of vaginal delivery with FHR abnormalities and with fetal hypoxia, the fetoplacental concentration of ET-1 was increased.

Identification of the pregnancy responsible for gestational trophoblastic disease by DNA analysis.

In three cases of choriocarcinoma, genetic loci including a variable number of tandem repeat regions were amplified by the polymerase chain reaction method on DNA from three established cell lines and from lymphocytes of patients and their husbands to identify the responsible pregnancy. Case 1, from whom NaUCC-3 was derived, had only one full-term fetal death. Case 2, from whom NaUCC-4 was derived, had one normal delivery followed by one complete molar delivery and one normal delivery. Case 3, from whom NaUCC-2 was derived, had one normal delivery followed by one complete molar delivery. In case 1, NaUCC-3 was found to be of parental origin and derived from the pregnancy with full-term fetal death. In cases 2 and 3, NaUCC-4 and NaUCC-2 were of probable androgenetic origin and were derived from the pregnancy with complete hydatidiform mole. We also conducted the restriction fragment length polymorphism method using case 1 samples, and it confirmed the results based on the polymerase chain reaction method product patterns. All nine cases of hydatidiform mole and three cases of invasive mole were of androgenetic origin. The polymerase chain reaction method thus makes it possible to identify easily the pregnancy responsible for choriocarcinoma using only a few specimens without isotopes.

Oxytocin is hydrolyzed by an enzyme in human placenta that is identical to the oxytocinase of pregnancy serum.

The hydrolysis of oxytocin (OT) by human placental subcellular fractions and pregnant sera was studied in the presence of bestatin, a potent inhibitor of aminopeptidases, and the antibody against pregnant serum oxyotocinase (P-LAP)(EC 3.4 11.3) by measuring liberated amino acids by high performance liquid chromatography (HPLC). Our immunotitration study and the effect of bastatin on the oxytocin-degrading protease showed that the initiating and responsible protease in oxyotocin degradation in human placenta and pregnant serum is P-LAP.

Initiating and responsible enzyme of arginine vasopressin degradation in human placenta and pregnancy serum.

The hydrolysis of arginine vasopressin (AVP) by human placental subcellular fractions and pregnancy sera was studied in the presence of selective inhibitors and the antibody against pregnancy serum oxytocinase (P-LAP) (EC 3.4.11.3) by measuring liberated amino acids by high-performance liquid chromatography (HPLC). AVP degradation by placental subcellular fractions and pregnancy sera was inhibited by bestatin. The IC50 values of bestatin on AVP degradation by placental subcellular fractions and pregnancy sera were similar to that of this inhibitor on the P-LAP measured by L-Leu-p-nitroamnilide as a substrate (LAP activity), which we reported previously. Our immunotitration study clearly showed that the initiating and responsible protease in AVP degradation in human placenta and pregnancy serum is P-LAP. Since N-benzylcarbonyl-valyl-prolinal (Z-Val-prolinal), a selective inhibitor of post-proline endopeptidase, and phosphoramidon, a putative endopeptidase-24.11 inhibitor, could not significantly influence the degradation of AVP by placental microsomal fractions. Neither enzyme seems to be actively involved in AVP degradation.

Interaction between pregnancy-induced bioactive peptides and the placental proteases.

Studies have shown that placental proteases metabolize vasoactive peptides, possibly derived from the fetus, and protect the exchange of peptide hormones across the placenta in order to maintain feto-placental homeostasis. Changes in maternal serum protease activities were useful for monitoring pre-eclampsia and predicting the onset of labour. The study showed that possible role of oxytocinase in the maintenance of gestation and the possible involvement of angiotensinase in the attenuated pressor responses to angiotensin II during pregnancy, respectively. In addition, the ratio of peak systolic over least diastolic pressure (S/D) of uterine or umbilical artery assessed by the Doppler technique was closely correlated with the concentrations of maternal serum proteases in pre-eclampsia, which suggested that placental proteases might control utero-placental circulation via the regulation of concentrations of vasoactive peptides in uteroplacental circulation.

Possible involvement of placental proteases in bradykinin (BK) degradation.

The hydrolysis of bradykinin (BK) by human placental subcellular fractions and pregnancy sera was studied in the presence of inhibitors by measuring amino acids liberated from BK by high-performance liquid chromatography. The effects of the inhibitors DL-2-mercaptomethyl-3-guanidinoethylthiopropionic acid (MGTA, for kininase I), phosphoramidon (for endopeptidase 24.11) and captopril and rentiapril (for angiotensin-converting enzyme [ACE, kininase II]) suggested the essential roles of the above three proteases in BK degradation: among the three proteases, kininase I and endopeptidase 24.11 appeared to be the most important in kininase action in the placenta microsomes, whereas kininase I and ACE appeared to be the most important in kininase action in the placental cytosol, lysosome and pregnancy serum. Measurements of BK concentrations in the umbilical arterial blood, umbilical venous blood and maternal plasma revealed higher concentrations in the mother than in the fetus. The present data suggest that degradation of BK in the placenta and pregnancy serum might contribute to the gradient of BK between mother and fetus.

Timing of insults causing abnormal outcome in preterm infants 1989-1992.

OBJECTIVE: The purpose of this study was to clarify the influence of timing of brain insults causing abnormal outcome in preterm infants. METHODS: One hundred and thirty-one preterm infants were examined. The timing of brain insult was estimated from EEG or clinical findings. Development was assessed until a corrected age of 48 months. RESULTS: 39% and 4% of infants, respectively, born before and after the 28-week time point subsequently died (P < 0.05). Abnormal development was observed in 16% of the first group and 13% of the second (N.S.). None of those born before 28 weeks showed intrauterine injuries while nine of the infants which were born after this time showed intrauterine injuries (P < 0.05). Fetal distress was noted in all infants suffering neonatal death born after 28 weeks. CONCLUSION: Intrauterine brain insult was concluded to be the cause of neonatal death or abnormal development in many infants born after 28 weeks.

Fetal heart rate patterns associated with periventricular leukomalacia.

OBJECTIVE: Our purpose was to assess the applicability of fetal heart rate (FHR) monitoring to detect fetuses at risk of developing periventricular leukomalacia (PVL). METHODS: FHR tracings obtained for babies delivered under 33 weeks' gestation and with a birth weight under 2000 g were assessed for baseline heart rate, variability, deceleration and "flip flap' (an oscillatory tracing pattern). RESULTS: PVL developed in 19 of the 103 infants studied. All of these infants were among the fetuses who exhibited average and increased variability. In addition, PVL was detected in 10 (47.6%) of the 21 flip flap positive fetuses, and in 9 (11.0%) of the 82 flip flap negative fetuses. The incidence of PVL was significantly higher in the flip flap positive fetuses (P < 0.005). CONCLUSION: The possibility that an unstable intrauterine environment, reflected by a flip flap pattern, is related to the subsequent development of PVL is indicated.

Timing of periventricular leukomalacia using neonatal electroencephalography.

OBJECTIVE: To estimate the timing of brain damage involved in the onset of periventricular leukomalacia in the perinatal period we recorded and analyzed neonatal electroencephalograms (EEGs). METHODS: Twenty-four preterm birth infants proved by real time ultrasonic examination or MRI to be suffering from periventricular leukomalacia underwent serial electroencephalography from soon after birth. RESULTS: Thirteen (54%) demonstrated intrauterine injury patterns, 2 infants (8%) showed postnatal injury, and in the remaining 9 cases (38%) the time of injury could not be determined by electroencephalography. Antepartum maternal hemorrhage (6), premature rupture of membranes (3), twining (3), chorioamnionitis (2), and perinatal asphyxia (2) were complications encountered in the group with intrauterine injury patterns. CONCLUSIONS: Our observations suggest that more than half of periventricular leukomalacia cases are associated with premature birth infants showing intrauterine injury patterns on electroencephalography, indicating the existence of intrauterine insult.

Fetal sacrococcygeal teratoma visualized by ultra-fast T2 weighted magnetic resonance imaging.

We report here a fetal sacrococcygeal teratoma found at 26 weeks of gestation. An ultra-fast T2 weighted imaging method enables the clear visualization of morphological details of the fetus without motion artifacts. Complete surgical resection was performed immediately after cesarean birth, and no evidence of tumor recurrence was confirmed at 1 year of age.

Pregnancy and successful delivery in a patient with triple heart valve prosthesis.

A 42-year-old patient had a history of rheumatic fever in childhood. At 37 years of age, she underwent a triple heart valve replacement; thereafter, she was followed with the administration of warfarin and methyldigoxin. Her third pregnancy occurred with the last menstruation on 12 March 1990. At the 30th gestational week, she was admitted to the Nagoya University Hospital for the control of anticoagulation and rest. She delivered by cesarean section a healthy male infant weighing 2070 g at 34 weeks of gestation. The post-operative course was uneventful. This report shows that a patient with a three heart valve prosthesis tolerated pregnancy well under intense medical supervision.

Decrease in severity of intrauterine growth retardation in subsequent pregnancies.

OBJECTIVE: Intrauterine growth retardation (IUGR) is likely to recur in a subsequent pregnancy. We investigated the obstetric features of recurrent cases and the severity of IUGR by comparing initial and subsequent deliveries. METHODS: From a total of 12,567 deliveries, 95 women who were delivered of small-for-gestational-age (SGA) infants and who became pregnant again within 5 years, were enrolled. A retrospective, comparative study of recurrent and non-recurrent groups was performed. RESULTS: Twenty-two of ninety-five women gave birth to SGA infants again, and a relatively high risk of recurrence was confirmed, but no single recurrence-associated features were revealed. Within the recurrent group, the degree of IUGR was more severe in only five cases in the subsequent pregnancy. CONCLUSIONS: IUGR tends to recur, but does not increase in severity in most cases. We conclude that there is no need for excessive concern about the recurrence of IUGR.