Abstract:
OBJECTIVE:Placental lipid peroxides and thromboxane are abnormally increased in preeclampsia. Thromboxane is a potent vasoconstrictor of the placental vasculature. Peroxides stimulate cyclooxygenase (prostaglandin H synthase), and thereby could increase thromboxane, to cause vasoconstriction in the placenta. This study was performed to test the hypothesis that peroxides would produce vasoconstriction in the human placenta by stimulating thromboxane production. STUDY DESIGN:Isolated human placental cotyledons were perfused for 20-minute intervals with 100 mumol/L t-butyl hydroperoxide alone, and during and after perfusion with low-dose aspirin (5 x 10(-5) mol/L) (n = 6) or the thromboxane receptor blocker SQ 29,548 (n = 2). Krebs-Ringer-bicarbonate buffer gassed with 95% oxygen and 5% carbon dioxide was used for the perfusion buffer. Perfusion pressure was monitored continuously, and effluent flow rates were measured during each experimental treatment. Maternal and fetal effluent samples were analyzed for thromboxane B2 and 6-keto-prostaglandin F1 alpha. RESULTS:Compared with control Krebs-Ringer-bicarbonate buffer perfusion, peroxide perfusion significantly increased (p < 0.05) vascular resistance (14 +/- 2 vs 25 +/- 3 mm Hg.min/ml, mean +/- SE, respectively), thromboxane B2 secretion (fetal 0.20 +/- 0.04 vs 1.65 +/- 0.26 ng/min, maternal 4.8 +/- 1.5 vs 8.1 +/- 2.1 ng/min) and 6-keto-prostaglandin F1 alpha secretion (fetal 21 +/- 5 vs 60 +/- 1.8 pg/min, maternal nondetectable). Peroxide perfusion increased the thromboxane B2/6-keto-prostaglandin F1 alpha ratio threefold on the fetal side. Subsequent perfusion with aspirin significantly blocked the peroxide-induced vasoconstriction (13 +/- 1 mm Hg.min/ml during aspirin + peroxide) and the peroxide-induced increase in the secretion of thromboxane B2 (fetal 0.52 +/- 0.12 ng/min, maternal 2.0 +/- 0.3 ng/min) and 6-keto-prostaglandin F1 alpha (fetal 30 +/- 8 pg/min). After perfusion with aspirin the thromboxane B2/6-keto-prostaglandin F1 alpha ratio declined. When the thromboxane receptor blocker was used instead of aspirin, maternal and fetal secretion rates of thromboxane were still significantly increased by peroxide perfusion, but there was no change in perfusion pressure or vascular resistance. CONCLUSIONS:(1) Peroxide induces placental vasoconstriction coincident with increased secretion of thromboxane; (2) low-dose aspirin blocks both increased thromboxane secretion and vasoconstriction, whereas a thromboxane receptor antagonist allows increased thromboxane secretion but prevents peroxide induced vasoconstriction; (3) therefore, peroxide induces vasoconstriction by stimulating thromboxane synthesis.
journal_name
Am J Obstet Gynecoljournal_title
American journal of obstetrics and gynecologyauthors
Walsh SW,Wang Y,Jesse Rdoi
10.1016/0002-9378(93)90044-jsubject
Has Abstractpub_date
1993-10-01 00:00:00pages
1007-12issue
4eissn
0002-9378issn
1097-6868pii
0002-9378(93)90044-Jjournal_volume
169pub_type
杂志文章abstract:OBJECTIVE:The prototype of surgical treatment for vulvar vestibulitis has been the Woodruff vulvoplasty. A simpler surgery could be less morbid, technically easier, and equally effective. STUDY DESIGN:Twelve patients underwent vestibular revision, nine with local anesthesia. They were followed up for between 6 months ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/s0002-9378(96)70200-4
更新日期:1996-06-01 00:00:00
abstract:OBJECTIVES:Our purpose was to develop a method to induce premature delivery in rats and to use this method to identify biochemical changes that are critical to cervical dilatation by comparison to changes that occur during term delivery. STUDY DESIGN:Rats were treated with antiprogestational agents onapristone or lilo...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1053/ob.1996.v175.a74254
更新日期:1996-09-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to understand the relationship between daily contextual factors and oral contraceptive (OC) adherence among students who attend college or graduate school. STUDY DESIGN:Data on OC adherence, demographics, contextual factors, and side-effects were collected as part of the accepta...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.ajog.2010.05.039
更新日期:2010-10-01 00:00:00
abstract:OBJECTIVE:The objective of the study was to identify correlates of perceived risk of carrying a Down syndrome-affected fetus or experiencing a procedure-related miscarriage among a diverse group of pregnant women. STUDY DESIGN:We conducted a cross-sectional survey of 1081 English-, Spanish-, or Chinese-speaking women ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2007.09.045
更新日期:2008-03-01 00:00:00
abstract::Vitamin D is an essential fat soluble vitamin and a key modulator of calcium metabolism in children and adults. Because calcium demands increase in the third trimester of pregnancy, vitamin D status becomes crucial for maternal health, fetal skeletal growth, and optimal maternal and fetal outcomes. Vitamin D deficienc...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2009.09.002
更新日期:2010-05-01 00:00:00
abstract::We provide a justification for preventive ethics in obstetric practice. Four clinical guides to resolving ethical conflicts between pregnant women and their physicians can be identified: (1) informed consent as an ongoing dialogue between the pregnant woman and her physician, (2) negotiation as a clinical strategy, (3...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(90)90374-g
更新日期:1990-02-01 00:00:00
abstract::The effects of magnesium sulfate in the cerebrovascular bed were studied both in vivo, by measuring cerebral blood flow in conscious nonpregnant goats, and in vitro, by recording isometric tension in isolated goat middle cerebral arteries. Injections of increasing doses (10 to 300 mg) of magnesium sulfate directly int...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(91)90401-c
更新日期:1991-11-01 00:00:00
abstract:OBJECTIVES:Our goal was to determine the degree of shunting through the ductus venosus in the human fetus and its possible association with fetal growth. STUDY DESIGN:Blood flow in the umbilical vein and the fetal ductus venosus was measured in 197 low-risk pregnancies in a cross-sectional ultrasonographic study at a ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/s0002-9378(00)70504-7
更新日期:2000-01-01 00:00:00
abstract::A retrospective study of 56 patients treated for carcinoma in situ of the vulva over a 24-year period has shown a relative increase in the occurrence of this neoplasm. Only 6.7% of patients in the first 14 years of the study period were less than 35 years of age, as compared with 29.3% in the last decade. In the earli...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(84)90669-0
更新日期:1984-11-15 00:00:00
abstract::This is the first case of a 65 year old healthy woman developing de novo mental confusion during treatment with 2 mg tolterodine twice daily. It is a rare complication of therapy for overactive bladder and resolved when dosage was reduced to 1 mg, although overactive bladder symptoms were still controlled. ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2007.04.051
更新日期:2007-08-01 00:00:00
abstract::This study was undertaken to evaluate the catecholamine response of the fetal rat to insulin-induced hypoglycemia in the mother. Twenty-four Sprague-Dawley rats at day 21 of gestation were used. Hypoglycemia was induced with regular insulin; then at timed intervals, the rats were anesthetized with pentobarbital. When ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(81)90317-3
更新日期:1981-02-15 00:00:00
abstract::Reanalysis of data on the ovulation method of natural family planning collected by the World Health Organization yields the following conclusions. The method is effective during perfect (correct and consistent) use, with a first-year probability of failure of 3.4%. However, it is extremely unforgiving of imperfect use...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/s0002-9378(11)90581-x
更新日期:1991-12-01 00:00:00
abstract:OBJECTIVE:Our purpose was to assess the adequacy of currently accepted criteria for the diagnosis of twin-to-twin transfusion syndrome. STUDY DESIGN:Between April 1991 and February 1992 nine consecutive women with twin gestations and ultrasonographic findings of marked growth discordance, coexistent oligohydramnios-po...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(93)90028-h
更新日期:1993-10-01 00:00:00
abstract:OBJECTIVE:The objective of the study was a cost minimization analysis of the laparoscopic sacral colpopexy (LSC) and total vaginal mesh (TVM). STUDY DESIGN:Primary clinical costs were derived from our randomized control trial comparing LSC and TVM and were compared using prices from privately- and publicly-conducted p...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.ajog.2011.12.012
更新日期:2012-05-01 00:00:00
abstract:BACKGROUND:Age-related decline in reproductive potential is mainly due to the increased incidence of aneuploidy. Furthermore, 2 recent studies have shown that euploid embryos of older women may have a lower implantation potential compared to those of younger women, suggesting that aging might compromise embryos beyond ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2018.11.1103
更新日期:2019-04-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to evaluate the impact of an interconception antibiotic regimen on endometrial microbial flora and histologic type. STUDY DESIGN:This was a secondary analysis of a double-blind randomized placebo-controlled trial of prophylactic metronidazole plus azithromycin that was given to ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.ajog.2007.01.014
更新日期:2007-03-01 00:00:00
abstract:OBJECTIVE:This study was undertaken to review pregnancy course and outcome in 56 pregnancies after the placement of a cervicoisthmic cerclage transvaginally. STUDY DESIGN:Fifty-three pregnant patients with unique indications such as previous failure of conventional cerclages or compromised cervical anatomy, underwent ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2005.02.127
更新日期:2005-06-01 00:00:00
abstract::If the parents do not want to take the 50% chance that a male fetus will be involved with an x-linked disease, it is desirable to predict fetal sex early enough to safely terminate pregnancy. Slides obtained from midcervical smears of 20 consecutive patients at different stages of gestation were stained with .5% aque...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(73)90541-3
更新日期:1973-03-15 00:00:00
abstract::A somewhat paradoxic aspect of childbirth is the association of this physiologic process with acute pain. The experience of pain during labor is the result of complex processing of multiple physiologic and psychosocial factors on a woman's individual interpretation of nociceptive labor stimuli. The nature of labor pai...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章,评审
doi:10.1067/mob.2002.121427
更新日期:2002-05-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to test the hypothesis that infusion of the oxytocin antagonist atosiban results in decreased preterm uterine activity in the human. STUDY DESIGN:A randomized, double-blind, placebo-controlled trial was performed. One hundred twenty women from 20 to 36 weeks' gestation with a co...
journal_title:American journal of obstetrics and gynecology
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1016/s0002-9378(94)70214-4
更新日期:1994-02-01 00:00:00
abstract:OBJECTIVE:Maternal diabetes alters placental glucose metabolism and maternofetal glucose transport. The purpose of this study was to determine whether genes involved in placental glucose uptake and transport were concomitantly altered, resulting in the observed changes in the state of maternal diabetes. STUDY DESIGN:B...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(94)90154-6
更新日期:1994-11-01 00:00:00
abstract::FloSeal hemostatic matrix has been reported to be effective for the control of intraoperative bleeding in various surgeries. We report 3 patients who experienced a possible allergic response to FloSeal with the formation of excessive granulation tissue and fibrosis that were associated with early postoperative pelvic ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2008.10.052
更新日期:2009-04-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to determine whether quantification of cervicovaginal fluid fetal fibronectin (fFN) improves diagnostic accuracy of spontaneous preterm birth (sPTB) in symptomatic women. STUDY DESIGN:A prospective blinded predefined secondary analysis of a larger study of cervicovaginal fluid f...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2012.10.890
更新日期:2013-02-01 00:00:00
abstract::The concentrations of certain steroids in arterial and ovarian venous blood were measured in 42 postmenopausal women undergoing hysterectomy for uterine disease. A concentration gradient across the ovary was found for testosterone in 21 women, for androstenedione in 16, for estradiol in 15, for estrone in 8, and for d...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(80)90287-2
更新日期:1980-11-01 00:00:00
abstract:OBJECTIVE:Our purpose was to test the hypothesis that severe placental insufficiency leads to reductions in fetal urine production and amniotic fluid volume in late-gestation fetal sheep. STUDY DESIGN:At 0.85 of gestation, chronically catheterized fetal sheep with ligated urachus were either embolized for 5 days by re...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1067/mob.2002.122291
更新日期:2002-05-01 00:00:00
abstract:OBJECTIVES:The purpose of this study was to provide a morphometric profile of endometrial granulated lymphocytes and to investigate qualitative and quantitative differences in leukocyte subsets in precisely timed luteal phase endometrial biopsies. STUDY DESIGN:Endometrial biopsies were obtained from 24 normal fertile ...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/s0002-9378(11)91568-3
更新日期:1992-09-01 00:00:00
abstract::A study of fetal activity was undertaken as the first step in a series of physiologic fetal movement studies. A simple, safe, noninvasive, clinically applicable method for studying fetal movement with a tocodynamometer is described. Four basic types of fetal movement have been seen and defined in terms of their durati...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(76)90467-1
更新日期:1976-09-01 00:00:00
abstract::Serum progesterone was assayed by the competitive protein-binding technique in 20 cases of gestational choriocarcinoma and one case of nongestational choriocarcinoma. Serum human chorionic gonadotropin (HCG) was simultaneously measured from the same blood samples by the hemagglutination-inhibition technique. Serum pro...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(75)90503-7
更新日期:1975-12-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to determine the effect of an obstetrics patient safety program on staff safety culture. STUDY DESIGN:We implemented (1) obstetrics patient safety nurse, (2) protocol-based standardization of practice, (3) crew resource management training, (4) oversight by a patient safety comm...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/j.ajog.2010.11.004
更新日期:2011-03-01 00:00:00
abstract::Retrospective review of 457 breech deliveries failed to reveal a significant improvement in neonatal mortality and morbidity rates for those delivered by cesarean section vs. vaginal delivery. A slight but insignificant improvement in salvage was found for the 1,000 to 1,500 gram weight category when delivery was by c...
journal_title:American journal of obstetrics and gynecology
pub_type: 杂志文章
doi:10.1016/0002-9378(79)90638-0
更新日期:1979-07-15 00:00:00