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Demetrios Rizos Demetrios Hassiakos Panagiota Grigori-Kostaraki Angeliki Sarandakou Demetrios Botsis Emmanuel Salamalekis 《黑龙江环境通报》2002,22(3):221-225
Recent studies suggest that leptin, the product of the obese gene, is produced by the placenta during pregnancy. The present study addressed the question whether second trimester maternal serum leptin could be altered by fetal Down syndrome or Edwards syndrome. Maternal serum leptin concentrations were measured in 18 pregnancies complicated with Down syndrome, six pregnancies complicated with Edwards syndrome and 183 uncomplicated pregnancies during the second trimester of pregnancy. The present results demonstrate that leptin concentrations in uncomplicated pregnancies slightly decrease from the 16th week of pregnancy, reaching a minimum of 18.8 ng/ml around the 20th week, and then rapidly increase to 28.2 ng/ml by the 24th week. Leptin correlation with maternal body weight decreases from r=0.695 at 16–17 week of gestation to r=0.544 at >22 weeks of gestation. There was no significant difference between the mean MoMs of Down syndrome- (0.926) or Edwards syndrome- (0.960) affected pregnancies and normal pregnancies (1.002). A weak correlation (r=0.18, p<0.02) was observed between corrected leptin MoMs and human chorionic gonadotrophin (hCG) MoMs in normal pregnancies. It is assumed that around the 20th week of pregnancy placental leptin production is activated or at least is accelerated and it is added to the amount of leptin produced by maternal adipose tissue. Fetal Down syndrome or Edwards syndrome does not seem to alter maternal leptin concentration and therefore leptin cannot be used as a marker for these chromosomal abnormalities in the early second trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Dr Iris Bartels Barbara Hoppe-Sievert Barbara Bockel Sabine Herold Julius Caesar 《黑龙江环境通报》1993,13(2):123-130
Serum levels of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and un-conjugated oestriol (uE3) were measured in serum samples of 4131 non-smoking and 1018 smoking women during the second trimester of pregnancy. The levels of all three analytes decreased with increasing body weight. The AFP median was significantly increased in smokers in a dose-response association; hCG decreased by 21 per cent and uE3 decreased by 3 per cent in smokers in a non-dose-related fashion. Regression functions for adjustment of serum levels for weight and smoking should be considered in risk estimation for Down syndrome in order to give a woman's individual risk more precisely. 相似文献
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Prenatal screening and diagnosis in a twin pregnancy is not straightforward. Once a twin pregnancy has been identified, women and their partners need time to consider the implications and decide whether they wish the pregnancy to be screened for Down syndrome or neural tube defects. We discuss here how multiple marker screening for Down syndrome and alpha-fetoprotein screening for neural tube defects can be carried out, given that this is the parents' chosen option and that the health professionals involved are capable of performing a diagnosis and selective feticide, should this arise. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Euan M. Wallace Budi Marjono David A. Brown Jennifer Crossley Stephen Tong David Aitken Sam Breit 《黑龙江环境通报》2004,24(3):224-226
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M. Grynberg O. Graesslin J. Teyssedre C. Quereux D. Gaillard F. Carré-Pigeon 《黑龙江环境通报》2007,27(6):552-554
We report the case of monozygotic (MZ) male twin fetuses with different Down syndrome (DS) phenotypes. Prenatal fetal sonography showed a bichorial biamniotic pregnancy with increased nuchal translucency in twin A and a cervical cystic hygroma and heart defect in twin B. Cytogenetic analysis performed after double amniocentesis showed free and homogeneous trisomy 21 in both twins. Monozygosity was confirmed by molecular analysis. The pregnancy was terminated at 17 weeks of gestation (WG). Postmortem analysis confirmed the phenotypic discordance. To our knowledge, this is the first reported prenatal diagnosis of MZ male twins with different Down syndrome phenotypes but identical karyotypes. We discuss the mechanisms involved in phenotypic discordance of monozygotic twins and particularly the role of environmental factors. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Marko Niemimaa Mikko Suonpää Seppo Heinonen Maija Seppälä Risto Bloigu Markku Ryynänen 《黑龙江环境通报》2002,22(3):183-185
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The value of maternal serum pregnancy-associated plasma protein (PAPP)-A in screening for Down syndrome in early pregnancy was assessed using stored samples. Seventeen cases of Down syndrome and 66 unaffected control pregnancies were studied. The median PAPP-A level in the cases was 0.42 multiples of the expected value in controls (p <0.0001). Eleven cases (65 per cent) had levels less than half the expected value compared with only six controls (9 per cent). A commercial assay kit is now needed so that prospective screening with this marker can begin. 相似文献
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David Krantz Terrence Hallahan Stephanie Ishack V. James Macri James N. Macri 《黑龙江环境通报》2006,26(12):1137-1141
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Maternal serum human thyroid-stimulating hormone (TSH) levels were investigated in chromosomally normal and Down syndrome pregnancies to determine whether TSH can be used as a marker for Down syndrome in the first trimester. Measurements were conducted on stored serum samples collected from 23 Down syndrome pregnancies and 115 unaffected pregnancies before chorionic villus sampling (CVS), between 9 and 11 completed weeks of pregnancy. The samples were matched for gestational age, maternal age, maternal weight and duration of storage of the serum sample. Maternal TSH concentration was slightly decreased in Down syndrome pregnancies, with a median of 0.84 multiples of the median (MoM). Maternal serum human chorionic gonadotropin (hCG) concentration was slightly elevated in Down syndrome pregnancies, with a median of 1.03 MoM. Both differences were not significant applying matched rank analysis (p=0.50 for TSH and p=0.43 for hCG). The association between TSH and hCG in unaffected pregnancies was also measured. The Spearman correlation coefficient between TSH and hCG was −0.21 which was statistically significant (p=0.02, 95% confidence interval −0.38 to −0.03). However, it was concluded that TSH is not a useful marker for distinguishing Down syndrome-affected pregnancies from normal pregnancies in the first trimester. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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In order to elucidate the consistency between generally used age-dependent risk values for Down syndrome (DS) and estimates of the probability of miscarriage in Down pregnancies we have compared expected numbers with estimated numbers of births with DS in Denmark had no intervention at all been carried out. The expected numbers were calculated from the distribution of newborn children according to maternal age combined with the age-related risk of DS. The estimated numbers of children that actually would have been born without any intervention were estimated from observed numbers of cases of DS, i.e. the cases born plus – with corrections because of the high probability of miscarriage in DS pregnancies – a proportion of those cases discovered prenatally. The analysis was carried out separately for mothers aged 35 years or older and for younger mothers. We found a high degree of compatibility between expected and estimated numbers, probably with a minor underestimation of the expected values for the older mothers. The performance of DS screening in Denmark in the period under consideration (1980–1998) is discussed in relation to the figures presented. Despite the fact that 11.8% of all pregnancies were subjected to an invasive diagnostic procedure, only about 38% of all births with DS were prevented. This means that in the period 1990–1998, reluctance to accept serological screening has indirectly resulted in the birth of almost 300 cases of DS in Denmark and at the same time the miscarriage of an unreasonable high number of normal fetuses. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献