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31.
Seher Basaran Peter Miny Ivar-Harry Pawlowitzki Jürgen Horst Wolfgang Holzgreve 《黑龙江环境通报》1988,8(4):315-320
Direct chromosome preparations were performed on placental villi obtained by ultrasoundguided needle aspiration between 18 and 37 weeks of pregnancy in 53 patients. The sampling yielded a sufficient amount of tissue with a maximum of two, and in most cases one, insertions. Placental biopsy is easily performed in cases of severe oligohydrammnios, where fetal blood sampling is usually more difficult. Direct karyotyping of placental villi is faster than chromosome analysis from fetal blood or application of the pipette method on amniotic fluid cells, and currently represents the most rapid approach to prenatal diagnosis of chromosomal abnormalities from the first to the third trimester of pregnancy. 相似文献
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Six cases are reported with discrepancies between the karyotypes of placental cells and cells from other fetal tissue. The respective findings were: (a) 48,+7,+18 resp. 47,+18. (b) 46, i(18q) resp. 46, del18(p11). (c) 46, XX resp. 46, XX/47, XXX. (d) 46, X, Yq+ and 46, XY resp. 46, XY. (e) 46/47,+12 resp. 46. (f) 46/47,+5 resp. 46. These differences were found in both early and term pregnancies. Care should be taken in deducing the fetal karyotype from the chromosomal pattern of placental cells. 相似文献
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Today, preimplantation genetic diagnosis (PGD) is offered in over 40 centres worldwide for an expanded range of genetic defects causing disease. This very early form of prenatal diagnosis involves the detection of affected embryos by fluorescent in situ hybridization (FISH) (sex determination or chromosomal defects) or by polymerase chain reaction (PCR) (monogenic diseases) prior to implantation. Genetic analysis of the embryos involves the removal of some cellular mass from the embryos (one or two blastomeres at cleavage-stage or some extra-embryonic trophectoderm cells at the blastocyst stage) by means of an embryo biopsy procedure. Genetic analysis can also be performed preconceptionally by removal of the first polar body. However, additional information is then often gained by removal of the second polar body and/or a blastomere from the embryo. Removal of polar bodies or cellular material from embryos requires an opening in the zona pellucida, which can be created in a mechanical way (partial zona dissection) or chemical way (acidic Tyrode's solution). However, the more recent introduction of laser technology has facilitated this step enormously. Different biopsy procedures at different preimplantation stages are reviewed here, including their pros and cons and their clinical applications. The following aspects will also be discussed: safety of zona drilling by laser, use of Ca2+/Mg2+-free medium for decompaction, and removal of one or two cells from cleavage-stage embryos. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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A. F. Hashish N. A. Monk M. P. F. Lovell-Smith L. M. Bardwell T. M. Fiddes R. J. M. Gardner 《黑龙江环境通报》1989,9(6):427-432
Trisomy 16 detected at chorion villus sampling (CVS) may reflect the placental but not the fetal karyotype. We describe a case in which the pregnancy continued until intrauterine death at 37 weeks. Cytogenetic study of two placental samples showed 47, +16 and 46,XX; the fetus was morphologically grossly normal, but fetal tissue culture was unsuccessful. Conservative management may be appropriate when trisomy 16 is detected at CVS and the pregnancy is normal ultransonographically. 相似文献
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Fossi MC Casini S Marsili L 《Environmental science and pollution research international》2006,13(3):204-207
- DOI: http://dx.doi.org/10.1065/espr2006.01.018
Background, Aims and Scope
Man-made Endocrine Disruptors (EDs) range across all continents and oceans. Some geographic areas are potentially more threatened
than others: one of these is the Mediterranean Sea. Levels of some xenobiotics are much higher here than in other seas and
oceans. In this paper we review the final results of a project in which the hypothesis that Mediterranean top predator species
(such as large pelagic fish and marine mammals) are potentially at risk due to EDs was investigated.
Methods In a four-year survey on the Mediterranean population of swordfish (Xiphias gladius), the potential toxicological effects
of organochlorine compounds (OCs) on specimens of swordfish and tuna fish (Thunnus thynnus thynnus), caught in the spawning
seasons from 1999 to 2002 in the Straits of Messina, Sicily (Italy), were investigated using vitellogenin (Vtg), Zona radiata
proteins (Zrp), and cytochrome P4501A (CYP1A) activities (EROD, BPMO). Tissues (skin and blubber) were obtained from Stenella
coeruleoalba, Tursiops truncatus, Delphinus delphis and Balaenoptera physalus from the western Ligurian Sea, between Corsica
and the French-Italian coast, and Ionic Sea using biopsy darts launched with a crossbow. Benzo(á)pyrene monoxigenase (BPMO)
activity was mesured in biopsies and cholrinated hydrocarbon levels were detected.
Results and Discussion We illustrate the need to develop and apply sensitive methodological tools, such as biomarkers (Vitellogenin, Zona Radiata
proteins and CYP1A activities) for evaluation of toxicological risk in Xiphias gladius and Thunnus thynnus thynnus), and nondestructive
biomarkers (CYP1A activities and fibroblast cell culture in skin biopsy), for the hazard assessment of threatened marine mammals
species (Stenella coeruleoalba, Tursiops truncatus, Delphinus delphis and Balaenoptera physalus) exposed to EDs.
Conclusion The present research shows that: a) Vtg and Zrp can be used as diagnostic tools for fish stocks hazard assessment in the
Mediterranean Sea; b) that CYP1A1 (BPMO) induction in cetaceans skin biopsy may be an early sign of exposure to EDs such as
OCs and a potential alert for transgenerational effects.
Recommendation and Outlook This research represents a warning signal of the potential reproductive alterations in marine top predators and suggest the
need for continuous monitoring to avoid reductions in population and biodiversity in the Mediterranean Sea. 相似文献
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We studied a family at risk for atypical TSD in which the index case showed, clinically, a late onset and a gradual psychomotor deterioration and biochemically, a residual hex. A activity in leucocytes. Two prenatal diagnoses of affected fetuses were made in this family, The first one on amniotic cells, the second one on trophoblast biopsy samples. Both of them were confirmed after abortion on cultured cells. Prenatal diagnosis of TSD, even of some atypical forms is possible using trophoblast biopsy, but formal confirmation should be obtained on cultured trophoblasts. 相似文献
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The feasibility of fetal renal biopsy has been investigated in order to assess the diagnostic value of the histological specimen. Two fetuses with a severe bilateral renal abnormality (multicystic dysplastic kidney, Meckel-Gruber syndrome with polycystic kidney) and one fetus with Down syndrome (no detectable structural anomaly) were sampled. Histological findings in the biopsy specimens of cases 1 and 2 were diagnostic of an early obstructive renal disease. In case 3 , the findings were consistent with normal development for gestational age of the kidney. Fetal renal biopsy is technically feasible; histological examination of the samples showed a good correlation with postnatal findings. Further studies of its diagnostic value are required. 相似文献