Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy最新文献

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The novel role of 3',5'-guanosine monophosphate (cGMP) on the differentiation of trophoblasts: comparison with the effects of 3',5'-adenosine monophosphate (cAMP). 3',5'-鸟苷单磷酸(cGMP)在滋养细胞分化中的新作用:与3',5'-腺苷单磷酸(cAMP)作用的比较。
K Sawai, C Azuma, M Koyama, K Hashimoto, T Kimura, Y Samejima, T Nobunaga, M Takemura, F Saji
{"title":"The novel role of 3',5'-guanosine monophosphate (cGMP) on the differentiation of trophoblasts: comparison with the effects of 3',5'-adenosine monophosphate (cAMP).","authors":"K Sawai,&nbsp;C Azuma,&nbsp;M Koyama,&nbsp;K Hashimoto,&nbsp;T Kimura,&nbsp;Y Samejima,&nbsp;T Nobunaga,&nbsp;M Takemura,&nbsp;F Saji","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We investigated the effects of 3',5'-guanosine monophosphate (cGMP) on the differentiation of human trophoblasts. Isolated cytotrophoblasts were cultured with 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) or 8-bromoadenosine 3'5-cyclic monophosphate (8-Br-cAMP) and then stained immunocytochemically with anti-human chorionic gonadotropin (anti-hCG) antibody to identify hCG expression as an index of differentiation. Concurrently, morphological changes from cytotrophoblasts to syncytiotrophoblasts were analyzed. Both 8-Br-cGMP and 8-Br-cAMP enhanced the expression of hCG in cultured cytotrophoblasts with the differentiation of cytotrophoblasts to syncytiotrophoblasts dose-dependently. With regard to trophoblast proliferation, 8-Br-cAMP but not 8-Br-cGMP enhanced [3H]thymidine uptake by these cells. hCG, a trophoblast-specific glycoprotein hormone has been identified as a potent growth factor for trophoblasts, also increased [3H]thymidine uptake and the intracellular 3',5'-adenosine monophosphate (cAMP) concentration. However, in this study, hCG did not increase the concentration of intracellular cGMP. We also showed that sodium nitroprusside (SNP), which is a donor of nitric oxide (NO), enhanced intracellular cGMP concentration. These results suggest that cGMP enhances trophoblast differentiation without affecting their proliferation, while cAMP enhances both differentiation and proliferation. We conclude that an alternative pathway mediated through cGMP is responsible for the differentiation of trophoblasts. NO may be involved in trophoblast differentiation with an increase in cellular cGMP level.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 4","pages":"244-52"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Induction of connexin 32 expression by potential embryonic signals in rabbit uterine epithelium. 兔子宫上皮细胞中潜在胚胎信号对连接蛋白 32 表达的诱导作用
B Antoskiewicz, G Müller, R Grümmer, E Winterhager
{"title":"Induction of connexin 32 expression by potential embryonic signals in rabbit uterine epithelium.","authors":"B Antoskiewicz, G Müller, R Grümmer, E Winterhager","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Connexin 32 induction is found in rabbit uterine epithelium as a response to embryo recognition. Here we have chosen this connexin 32 expression as a cell biological marker to define the type of a locally acting embryonic signal. 17 beta-estradiol, onapristone, catechol estrogen (4-hydroxy-estradiol), prostaglandins E2 and F2 alpha, db-cAMP, and glass beads as mechanical stimuli were given to pseudopregnant animals on day 4, 5 or 6 posthuman chorionic gonadotropin (hCG). The induction of connexin 32 corresponded to the time of implantation at days 6-8 post-hCG by immunohistochemistry and Northern blot analysis. Untreated pseudopregnant animals started to express connexin 32 on day 8 post-hCG. In animals treated with 4-hydroxy-estradiol, 17 beta-estradiol or prostaglandins, connexin 32 expression started 1 day earlier (day 7 post-hCG) and led to an enhanced connexin 32 expression on day 8 post-hCG compared to control animals. The antigestagen, onapristone, as well as cAMP did not alter the endogenous program. Mechanical stimuli led to a high expression of connexin 32 starting at day 7 post-hCG whereas in pregnancy the blastocyst induces connexin 32 expression from day 6 postcoitum onwards. Combination of mechanical stimuli with 17 beta-estrogen advanced the induction to day 6 post-hCG. We conclude that a mechanical stimulus in combination with 17 beta-estradiol induces connexin 32 synthesis in a similar manner as compared to the blastocyst during pregnancy.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 4","pages":"253-63"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The novel role of 3',5'-guanosine monophosphate (cGMP) on the differentiation of trophoblasts: comparison with the effects of 3',5'-adenosine monophosphate (cAMP). 3',5'-鸟苷单磷酸(cGMP)在滋养细胞分化中的新作用:与3',5'-腺苷单磷酸(cAMP)作用的比较。
K. Sawai, C. Azuma, M. Koyama, K. Hashimoto, T. Kimura, Y. Samejima, T. Nobunaga, M. Takemura, F. Saji
{"title":"The novel role of 3',5'-guanosine monophosphate (cGMP) on the differentiation of trophoblasts: comparison with the effects of 3',5'-adenosine monophosphate (cAMP).","authors":"K. Sawai, C. Azuma, M. Koyama, K. Hashimoto, T. Kimura, Y. Samejima, T. Nobunaga, M. Takemura, F. Saji","doi":"10.14847/JSIRIB1987.10.75","DOIUrl":"https://doi.org/10.14847/JSIRIB1987.10.75","url":null,"abstract":"We investigated the effects of 3',5'-guanosine monophosphate (cGMP) on the differentiation of human trophoblasts. Isolated cytotrophoblasts were cultured with 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) or 8-bromoadenosine 3'5-cyclic monophosphate (8-Br-cAMP) and then stained immunocytochemically with anti-human chorionic gonadotropin (anti-hCG) antibody to identify hCG expression as an index of differentiation. Concurrently, morphological changes from cytotrophoblasts to syncytiotrophoblasts were analyzed. Both 8-Br-cGMP and 8-Br-cAMP enhanced the expression of hCG in cultured cytotrophoblasts with the differentiation of cytotrophoblasts to syncytiotrophoblasts dose-dependently. With regard to trophoblast proliferation, 8-Br-cAMP but not 8-Br-cGMP enhanced [3H]thymidine uptake by these cells. hCG, a trophoblast-specific glycoprotein hormone has been identified as a potent growth factor for trophoblasts, also increased [3H]thymidine uptake and the intracellular 3',5'-adenosine monophosphate (cAMP) concentration. However, in this study, hCG did not increase the concentration of intracellular cGMP. We also showed that sodium nitroprusside (SNP), which is a donor of nitric oxide (NO), enhanced intracellular cGMP concentration. These results suggest that cGMP enhances trophoblast differentiation without affecting their proliferation, while cAMP enhances both differentiation and proliferation. We conclude that an alternative pathway mediated through cGMP is responsible for the differentiation of trophoblasts. NO may be involved in trophoblast differentiation with an increase in cellular cGMP level.","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"115 1","pages":"244-52"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80332579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 14
Influence of uterine growth factors on blastocyst expansion and trophoblast knob formation in the rabbit. 子宫生长因子对兔囊胚膨胀及滋养细胞球形形成的影响。
C Gründker, C Kirchner
{"title":"Influence of uterine growth factors on blastocyst expansion and trophoblast knob formation in the rabbit.","authors":"C Gründker,&nbsp;C Kirchner","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The effects of insulin-like growth factors (IGF-1 and IGF-2) on blastocyst expansion, and of basic fibroblast growth (FGF-2) on trophoblast knob formation were studied by in vitro culture of rabbit blastocysts. Both growth factors are present in the uterine secretions. Embryo culture was carried out in Ham's F10 supplemented with polyvinylpyrrolidone in the presence or absence of human recombinant growth factors in concentrations ranging from 1 to 100 ng/ml. IGF-1 stimulated expansion of late preimplantation blastocysts to levels found in vivo; after addition of 10 ng/ml, day-6.0 blastocysts increased their diameter within 24 h to 103% of that of day-7.0 blastocysts expanded in vivo (in comparison to 84% without growth factor), and day-7.0 blastocysts expanded to 108% (in comparison to 76% without growth factor). IGF-1 suppressed the synthesis of a pH 6.3/35-kDa protein. Addition of IGF-2 had no effects. FGF-2 effected formation of trophoblast knobs in day-7.0 blastocysts. After addition of 10 ng/ml, the trophoblast knobs appeared within 12 h of culture. The controls without FGF-2 were negative. The striking increase of FGF-2 concentration in the uterine secretion at day 7.0 is perhaps connected with the formation of trophoblast knobs in vivo. FGF receptor-1 was localized in the trophoblast knobs of day-7.5 blastocysts by the use of immunostaining.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 4","pages":"264-70"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Management of threatened abortion. 先兆流产的处理。
I Szabó, A Szilágyi
{"title":"Management of threatened abortion.","authors":"I Szabó,&nbsp;A Szilágyi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Threatened abortion is associated with bleeding and/or uterine cramping while the cervix is closed. This stage of abortion may progress to spontaneous incomplete or complete abortion. While this event may be considered a part of the quality control process in human reproduction, it is important to know the possible etiologies and when therapy might prevent pregnancy loss. The World Health Organization estimated that 15% of all clinically recognizable pregnancies and in spontaneous abortion, 50-60% of which are due to chromosomal abnormalities. Apart from the fetal factors, several maternal and probably paternal factors contribute to the causes of spontaneous abortion. The maternal factors that may be responsible for abortion include both local and systemic conditions such as infections, maternal disease states, genital tract abnormalities, endocrine factors and other miscellaneous causes (antiphospholipid antibodies, maternal-fetal histocompatibility, excessive smoking and other environmental toxicants, etc.). This review focuses on the management of threatened abortion, but it should be emphasized that the management to maintain pregnancy is reasonable only in those cases, in which the fetus is not seriously affected. It would not be beneficial to provide treatment that would permit chromosomally and anatomically abnormal embryos to survive to term. Treatment is feasible first of all in cases with maternal factors. Surgical procedures may precede pregnancy (correction of septate uterus, removal of a submucous leiomyomata) or may be performed usually in the second trimester (cervical cerclage). Maternal general diseases (diabetes, hypothyroidism) and infections should be treated accordingly. The most common entity to be treated in this category is luteal phase deficiency. Progesterone is the most important hormone for the maintenance of an early human pregnancy. Besides progesterone administration, human chorionic gonadotropin (hCG) also is the logical endocrine treatment of choice. In the pregnant woman hCG stimulates and optimizes hormonal production in the corpus luteum and may also influence the fetoplacental unit. The contribution of environmental, physical and chemical agents to the incidence of spontaneous abortion is controversial. They may be abortifacient even if they are not teratogenic. Exposure to environmental toxicants should be avoided. Paternal leukocyte immunotherapy has been associated with successful outcome in patients with unexplained repeated spontaneous abortion. This therapeutic approach is considered experimental, as there may be some significant risks. Associating maternal antiphospholipid antibodies with reproductive failure is a rapidly developing field. Administration of corticosteroids with low doses of aspirin has resulted in fetal salvage in women in whom antiphospholipid antibodies are present.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 4","pages":"233-40"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Human first-trimester placenta intra-arterial trophoblast cells express the neural cell adhesion molecule. 人妊娠早期胎盘动脉内滋养细胞表达神经细胞黏附分子。
J Pröll, A Blaschitz, M Hartmann, J Thalhamer, G Dohr
{"title":"Human first-trimester placenta intra-arterial trophoblast cells express the neural cell adhesion molecule.","authors":"J Pröll,&nbsp;A Blaschitz,&nbsp;M Hartmann,&nbsp;J Thalhamer,&nbsp;G Dohr","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The supposed influence of endometrial natural killer (NK) cells on the trophoblast invasion activities especially on intravasation of uteroplacental arteries in the non-pathogenic human first-trimester placenta was studied by means of immunohistochemistry. To identify extravillous trophoblast cells, smooth muscle cells, endothelia, endometrial glands, decidual stroma cells and endometrial NK cells, antibodies against cytokeratins, vimentin, smooth muscle cells, epithelium specific antigen and endothelial cells were employed. Furthermore, the immunohistochemical distribution patterns of CD56, CD57 and CD94 were studied and compared with the localization of invading trophoblast cells. Remodelling and dilatation of uteroplacental arteries starts before trophoblast cells can be found in the vicinity of the vessels. Nevertheless, subsequent trophoblast invasion of the arterial wall will lead to media destruction and intravasation only on focally restricted areas. This process is accompanied by the disappearance of endothelial cells and the immediate expression of the neural cell adhesion molecule (N-CAM, CD56) by intra-arterial trophoblast cells, which are eventually beginning to form intraluminal plugs. These findings led us to the conclusion that in the human pregnancy-induced physiological changes of the uteroplacental blood flow and the peripheral blood NK cell activity is not only, but also, due to the effect of CD56 expression by intra-arterial trophoblast cells.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 4","pages":"271-5"},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20292551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Sonography in the first trimester screening of trisomy 21 and other fetal aneuploidies. 超声在孕早期筛查21三体和其他胎儿非整倍体。
B Brambati, L Tului, E Alberti
{"title":"Sonography in the first trimester screening of trisomy 21 and other fetal aneuploidies.","authors":"B Brambati,&nbsp;L Tului,&nbsp;E Alberti","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 3","pages":"155-67"},"PeriodicalIF":0.0,"publicationDate":"1996-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20294094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Implantation and early pregnancy loss. A report and relevant abstracts from a conference held in Paris, February 1996. 植入和早期妊娠丢失。1996年2月在巴黎举行的一次会议的报告和有关摘要。
F Ferré
{"title":"Implantation and early pregnancy loss. A report and relevant abstracts from a conference held in Paris, February 1996.","authors":"F Ferré","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 3","pages":"219-20"},"PeriodicalIF":0.0,"publicationDate":"1996-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Ontogeny of glucose transport systems in the placenta and its progenitor tissues. 胎盘及其祖组织中葡萄糖转运系统的个体发生。
T Hahn, G Desoye
{"title":"Ontogeny of glucose transport systems in the placenta and its progenitor tissues.","authors":"T Hahn,&nbsp;G Desoye","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Glucose is the primary substrate for placental and fetal metabolism, however, it can be synthesized in the fetus from placentally transferred substrates at best in minimal amounts. Therefore, the growing glucose requirements of the fetus throughout pregnancy must be met by increases in placental transport capacity. Results reviewed here indicate that the GLUT1 isoform represents the major glucose transporter species in human, and very likely in all mammalian, placentae as well as in fetal membranes and its progenitor tissues. This isoform is abundant in all placental cell populations including those fronting to the maternal and fetal circulation independent of anatomical differences of the placentae. The developmental changes of GLUT1 mRNA are controversial but the amount of GLUT1 protein tends to increase during pregnancy until term. GLUT1 seems also to play the predominant role in glucose uptake in the oocytes and preimplantation cleavage stages of rodents. Its mRNA and protein levels increased during preimplantation development. Furthermore, GLUT1 was demonstrated in the trophectoderm of mouse blastocysts, the direct progenitor tissue of the placenta. GLUT2 is generally not detected in the chorioallantoic placenta. If present at all, GLUT3 seems to be the only candidate for complementing GLUT1 in placental glucose uptake and transport function. The absence of the insulin-sensitive GLUT4 in the placenta is in line with the current consensus of insulin-independent glucose transport. The fructose transporter GLUT5 was only detected in human spermatozoa. All data available at present underline the paramount importance of GLUT1 for glucose transfer in the developing fetoplacental unit.</p>","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 3","pages":"168-82"},"PeriodicalIF":0.0,"publicationDate":"1996-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20294095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Current progress in early pregnancy investigation. 早期妊娠研究进展。
B M Polliotti
{"title":"Current progress in early pregnancy investigation.","authors":"B M Polliotti","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":11444,"journal":{"name":"Early pregnancy : biology and medicine : the official journal of the Society for the Investigation of Early Pregnancy","volume":"2 3","pages":"207-18"},"PeriodicalIF":0.0,"publicationDate":"1996-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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