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101.
Uzi Gafter Benjamin Sredni Jacob Segal Yona Kalechman 《Journal of clinical immunology》1997,17(5):408-419
Spontaneous recurrent abortion (SRA) has been treated by means of immunization with paternal or third-party white blood cells, yet the immunological basis for SRA and for the role of immunization protocols in pregnancy outcome remains controversial. To elucidate this question, nine women with SRA were immunized with paternal mononuclear cells and studied before and 2 weeks after immunization. Seven women who became pregnant gave birth to live newborns. Secretion of the T helper 1 cytokines IL-2 and interferon- by patients' mononuclear cells decreased, while production of IL-10 increased. The levels of natural killer and lymphokine-activated killer cell-mediated cytotoxicity were markedly decreased. Monocyte functions such as secretion of IL-l, tumor necrosis factor a, IL-6, and cytotoxic activity decreased concurrently with elevations in IL-10 and transforming growth factor secretion. Production of IL-12, a pivotal regulatory cytokine, decreased. Furthermore, B7/1 expression on patients' mononuclear cells was downregulated. This resulted in a decrease in monocyte costimulatory activity of purified T cells with soluble anti-CD3, paralleled by a decline in allogeneic proliferative responses. These results suggest that the improved pregnancy success rate in women with SRA following immunization may be partly related to suppression of cell-mediated immunity and monocyte and natural killer cell activity. 相似文献
102.
Hori S Nakano Y Furukawa TA Ogasawara M Katano K Aoki K Kitamura T 《American journal of reproductive immunology (New York, N.Y. : 1989)》2000,44(5):299-302
PROBLEM: The preconceptional natural-killer cell (NK) activity predicts subsequent miscarriage among women with unexplained recurrent spontaneous abortion (RSA). Psycho-neuro-immuno-endocrine network has recently been proposed as a mechanism for abortions. We therefore examined which psychosocial factors influenced the NK activity among women with RSA. METHOD OF STUDY: We measured the preconceptional NK activity of 61 women with a history two consecutive unexplained first-trimester miscarriages and no live births. We also administered semi-structured interviews and a battery of self-report questionnaires to assess their social support, personality, self-esteem and psychiatric symptoms. RESULTS: The preconceptional NK activity was negatively correlated with the women's neuroticism personality trait (r= -0.32, P = 0.01) and current depressive symptoms (r = -0.26, P= 0.05), and positively correlated with their self-esteem (r = 0.34, P = 0.01). CONCLUSIONS: In addition to several substances such as transforming-growth-factor beta and granulocyte-macrophase colony-stimulating factor, we found that low neuroticism, low depression scale score and high self-esteem contributed to high NK activity among women with RSA. 相似文献
103.
104.
Partial duplication 16q: report of two affected siblings resulting from a maternal translocation and literature review 总被引:1,自引:0,他引:1
Two siblings with a partial duplication 16q, born to a woman with a balanced translocation (6;16), are described. The first infant died at 8 weeks of age; the second died at 4 months. Fifteen other cases of duplications involving 16q have been reported, all of them derived from a balanced parental translocation. The most frequent physical findings have included dysmorphic facies characterized by high forehead, prominent nose, antimongoloid slant, malformed ears, and micrognathia, as well as flexion contractures of the joints, deformity of the feet, and genital hypoplasia in the male. Anorectal, intestinal and cardiac malformations were less frequent findings. Most of the affected infants died at ages ranging from 8 days to 6 months. The few with longer survival (up to 6 years) had a shorter, more distal segment duplication of chromosome 16. Although intrauterine growth retardation and microcephaly were not always present at birth, most of the infants had postnatal growth failure. The phenotypic and clinical findings of the two infants in this report are compared with those of previously reported cases, from which there appears to be correlation of the length of the 16q duplication with clinical phenotype and survivals. 相似文献
105.
Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (1010 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority ratio (218). In direct observation of single females with equal numbers of males (33) as controls,O males courted less and more slowly thanR males, but females mated with either type without bias. When unequal (41), the minority males were successful at more than twice the frequency expected. Whether successful or not, the minority males did not change their level of courtship, and thus cannot be said to compensate for their frequency in any way. The time between first courtship and mating was less for the minority males than for the majority males. We discard the hypothesis that the minority male will be accepted immediately or ahead of a majority male, because the opposite tended to occur: that if a minority male courted first he was less likely to be successful than if he waited until the majority courted. Our results then are in conformity with the hypothesis that a female samples males and their courtship cues, thus becoming habituated to the majority of the first courting male, but she accepts a male with a cue different from that which she originally detected but avoided. That male is most often the minority.This research was supported in part by National Science Foundation Grants GB-34206 to August 31, 1974, and BMS 72-02110 after that date. 相似文献
106.
Baird David T.; Sukcharoen Nares; Thong K.Joo 《Human reproduction (Oxford, England)》1995,10(6):1521-1527
Mifepristone (600 mg) in combination with a prostaglandin hasbeen demonstrated to be a safe, acceptable alternative to vacuumaspiration for induction of abortion in the first 9 weeks ofpregnancy. However, the efficacy and side-effects of differentprostaglandins used in combination with mifepristone have notbeen assessed in a randomized trial. In this study, 800 womenseeking an abortion at gestational age 63 days amenorrhoea wererandomized to receive either 0.5 mg gemeprost by vaginal pessary(group I) or 600 µg misoprostol (group II) by mouth 48h after taking 200 mg mifepristone by mouth. The side-effectsand number of complete abortions were used as measures of efficacy.There was no significant difference in the rate of completeabortion between group I [96.7%; 95% confidence interval (CI)94.998.5%, n = 391] and group II (94.6%; 95% CI 92.396.9,n = 386). It was not possible to assess the outcome with certaintyin the remaining 23 women. However, there were significantlymore ongoing pregnancies in the women who received misoprostolthan in those who received gemeprost (nine versus one, P <0.01) and in eight of these 10 women the gestation was >49days. Fewer women in group II required analgesia than in groupI (48 versus 60%, P < 0.001) although the number requestingopiate was similar in each group (6.9 versus 5.2%, P > 0.4).The incidence of nausea and vomiting after misoprostol (47.8and 21.9% respectively) was higher (P < 0.001) than aftergemeprost (33.9 and 12% respectively). The incidence of infectionand heavy bleeding was low in both groups (<2%) and onlyone woman required blood transfusion. We conclude that the recommendeddose of mifepristone and gemeprost can be reduced without impairingclinical efficacy in pregnancies up to 63 days amenorrhoea.Misoprostol is a safe alternative prostaglandin but has a higherincidence of ongoing pregnancies especially at gestation after49 days amenorrhoea. 相似文献
107.
The emerging role of immunoregulation of fibrinogen-related procoagulant Fgl2 in the success or spontaneous abortion of early pregnancy in mice and humans. 总被引:12,自引:0,他引:12
D A Clark J W Ding G Chaouat C B Coulam C August G A Levy 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,42(1):37-43
PROBLEM: Abortion of chromosomally normal embryos in the CBA X DBA/2 mating combination is triggered by release of Th1 cytokines (tumor necrosis factor [TNF]-alpha, interferon [IFN]-gamma, and interleukin [IL]-1), which cause abortion via a novel prothrombinase, Fgl2, and polymorphonuclear leukocytes. The site of activation may be maternal vascular endothelium on arteries and veins nourishing the placenta. Activation of coagulation is also prominent in spontaneous abortion of chromosomally normal human embryos. We asked where is Fgl2 up-regulated in the uterus in murine abortions, and if similar Fgl2 expression occurs in human pregnancy failure. METHODS: Control CBA X DBA/2 pregnant mice, or from mice injected with TNF-alpha + IFN-gamma on day 7.5 of gestation, were removed on day 8.5, fixed, sectioned, and subject to in situ hybridization for Fgl2. Sections were also stained for fibrin. Elective first trimester termination samples or biopsies taken early in the course of a recurrent miscarriage were similarly fixed, sectioned, and analyzed by in situ hybridization. Control and cytokine-treated mice were anticoagulated with heparin, an activator of antithrombin III, and/or the direct anti-thrombin inhibitor hirudin. RESULTS: Low level Fgl2 expression localized to basal decidua remote from the embryo was noted in control mice; cytokine treatment, which causes greater than 80% of abortions, produced a striking up-regulation in this area as well as in a band at the junction of decidua and myometrium. Trophoblast also became strikingly positive. Fgl2 expression was associated with increased fibrin staining. Anticoagulation significantly protected against abortions, but doses were limited by the complication of retroplacental hemorrhage. In tissue from normal first trimester pregnancy, minimal Fgl2 positivity was seen in some villous syncytiotrophoblast, in villous stroma, cytotrophoblast, and in some cells in decidua. In spontaneous abortion of normal embryo, striking Fgl2 positivity was seen in syncytiotrophoblast and extravillous cytotrophoblast, in association with areas of thrombus formation. CONCLUSIONS: Fgl2 appears to be physiologically expressed and may protect against the internal danger of maternal and/or fetal bleeding during pregnancy and at parturition; a role in inhibiting transplacental traffic is also possible. External dangers in the form of stress, endotoxin, and antigens eliciting Th1 cytokine responses upregulate Fgl2 prothrombinase in trophoblast as well as in decidua, which results in spontaneous abortion of immunogenetically "weaker" embryos. 相似文献
108.
Fiala C Aronsson A Granath F Stephansson O Seyberth HW Watzer B Gemzell-Danielsson K 《Human reproduction (Oxford, England)》2005,20(12):3414-3418
BACKGROUND: The pharmacokinetics of a novel slow-release (SR) misoprostol was studied and compared to conventional misoprostol. METHODS: Thirty-one women, pregnant between 8 and 12 weeks, requesting surgical abortion were randomly allocated to receive orally 400 microg conventional misoprostol, 400 microg SR misoprostol or 800 microg SR misoprostol. Venous blood samples were taken at 0, 30, 60, 120, 240 and 360 min after the administration of misoprostol. Misoprostol acid (MPA) was determined in serum samples using liquid chromatography/tandem mass spectrometry. RESULTS: Serum peak concentration (Cmax) was highest for conventional oral misoprostol. The time to peak concentration (Tmax) was similar for all groups. The area under the curve up to 360 min was similar for conventional and for 800 microg SR misoprostol and significantly greater for these groups compared to 400 microg SR misoprostol (P = 0.013). CONCLUSION: The new SR form of misoprostol demonstrated lower peak levels but longer-lasting elevation in plasma levels compared to conventional oral misoprostol. The AUC for 800 microg SR misoprostol was similar to that of 400 microg of conventional oral misoprostol. SR misoprostol may offer an alternative to repeated administration of oral misoprostol or to vaginal administration. 相似文献
109.
High NK cell activity in early pregnancy correlates with subsequent abortion with normal chromosomes in women with recurrent abortion 总被引:12,自引:0,他引:12
Yamada H Kato EH Kobashi G Ebina Y Shimada S Morikawa M Sakuragi N Fujimoto S 《American journal of reproductive immunology (New York, N.Y. : 1989)》2001,46(2):132-136
PROBLEM: The aim of this study was to assess the role of natural killer (NK) cells in pregnant women with a history of recurrent spontaneous abortion (RSA). METHOD OF STUDY: Consecutive 66 pregnant women with a history of RSA were prospectively assessed for peripheral NK cell activity, percentage of the NK cell subsets, and subsequent pregnancy outcome. RESULTS: NK cell activity in women with subsequent live birth (group I) at 4-5 gestational weeks (GW) (mean +/- SD, 32.5 +/- 12.31%) significantly decreased at 6-7 GW (28.1 +/- 12.1%) and at 8 9 GW (28.0 +/- 11.8%). NK cell activity in women with subsequent abortion with normal chromosomes (group II) at 6 7 GW (41.2 +/- 19.0%) was significantly higher than that in group I women, while NK cell activity at 6-7 GW in women with subsequent abortion with abnormal chromosomes (group III) was the same as the level in group I women. CONCLUSIONS: High NK cell activity at 6-7 GW correlates with subsequent abortion with normal chromosomes. 相似文献
110.
J Sj?berg 《Human reproduction (Oxford, England)》1987,2(7):615-616
Serum concentrations of pregnancy-associated plasma protein A (PAPP-A) were measured in patients with pregnancy-related gynaecologic emergencies including ectopic pregnancy (n = 124) and intrauterine abortion (n = 40). The results were compared with those in normal pregnancy (n = 136) and non-pregnant women (n = 460). In ectopic pregnancy and intrauterine abortion, the PAPP-A levels were lower than in normal pregnancy. In patients with a pregnancy-related gynaecologic emergency PAPP-A was undetectable in 82% of the ectopic pregnancies and in 55% of the intrauterine abortions. Considering the frequency of ectopic pregnancy (35.8%) and intrauterine abortion (52.3%) among all patients with pregnancy-related disorders, the likelihood that a pregnant patient with undectable PAPP-A has an ectopic pregnancy is 30%, and intrauterine abortion is 29%. These results indicate that although PAPP-A levels in ectopic pregnancy and intrauterine abortion are lower than in normal pregnancy, PAPP-A measurement cannot be used to distinguish between ectopic pregnancy and intrauterine abortion. 相似文献