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Fetal Samples (fetal + sample)
Selected AbstractsParvovirus B19 infection in pregnancy: Quantitative viral DNA analysis using a kinetic fluorescence detection system (TaqMan PCR)JOURNAL OF MEDICAL VIROLOGY, Issue 2 2002Antje Knöll M.D. Abstract Human parvovirus B19 infections are common in the general population, and infection during pregnancy may cause hydrops fetalis and fetal death. To initiate adequate treatment, accurate laboratory diagnosis is essential. The most sensitive tests are nested PCR systems, but these assays provide semiquantitative results at best. A parvovirus B19 DNA assay was developed based on the real time TaqMan PCR. This method was calibrated on the basis of serial plasmid dilutions and tested with an international parvovirus B19 standard. The assay was capable of quantifying parvovirus B19 DNA from one to about 5,×,107 genome equivalents per reaction (corresponding to 100 to 5,×,109 genome equivalents per ml serum). Samples from 51 pregnant women with suspected acute parvovirus B19 infection were tested, and positive PCR results were obtained in at least one of the materials investigated in 41 cases. The median viral DNA load in maternal blood samples was 1.3,×,104 copies/ml (range 7.2,×,102,2.6,×,107). Maternal virus DNA concentration was not associated with the presence of maternal symptoms and/or fetal complications. As the stage of infection was not known in the majority of cases, our data do not exclude an association between peak levels of parvovirus B19 DNA and the development of complications. Maternal sera and corresponding fetal material were available for concurrent testing from 15 DNA-positive cases: in most fetal samples, viral DNA concentrations were several orders of magnitude higher (up to 2.1,×,1012 copies/ml) compared to the corresponding maternal blood samples. J. Med. Virol. 67:259,266, 2002. © 2002 Wiley-Liss, Inc. [source] Recent advances in non-invasive prenatal DNA diagnosis through analysis of maternal bloodJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 6 2007Akihiko Sekizawa Abstract Prenatal diagnosis of aneuploidy and single-gene disorders is usually performed by collecting fetal samples through amniocentesis or chorionic villus sampling. However, these invasive procedures are associated with some degree of risk to the fetus and/or mother. Therefore, in recent years, considerable effort has been made to develop non-invasive prenatal diagnostic procedures. One potential non-invasive approach involves analysis of cell-free fetal DNA in maternal plasma or serum. Another approach utilizes fetal cells within the maternal circulation as a source of fetal DNA. At the present time, fetal gender and fetal RhD blood type within RhD-negative pregnant women can be reliably determined through analysis of maternal plasma. Furthermore, genetic alterations can be diagnosed in the maternal plasma when the mother does not have the alterations. However, the diagnosis of maternally inherited genetic disease and aneuploidy is limited using this approach. Non-invasive prenatal diagnosis through examination of intact fetal cells circulating within maternal blood can be used to diagnose a full range of genetic disorders. Since only a limited number of fetal cells circulate within maternal blood, procedures to enrich the cells and enable single cell analysis with high sensitivity are required. Recently, separation methods, including a lectin-based method and autoimage analyzing, have been developed, which have improved the sensitivity of genetic analysis. This progress has supported the possibility of non-invasive prenatal diagnosis of genetic disorders. In the present article, we discuss recent advances in the field of non-invasive prenatal diagnosis. [source] Distribution of saquinavir, methadone, and buprenorphine in maternal brain, placenta, and fetus during two different gestational stages of pregnancy in miceJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 8 2009Lisa D. Coles Abstract Efflux transporters such as P-glycoprotein (P-gp) play a critical role in the maternal-to-fetal and blood-to-brain transfer of many drugs. Using a mouse model, the effects of gestational age on P-gp and MRP expression in the placenta and brain were evaluated. P-gp protein levels in the placenta and brain were greater at mid-gestation (gd 13) than late-gestation (gd 18). Likewise, brain MRP1 levels were greater at mid-gestation, whereas, placental levels were greater at late-gestation. To evaluate these effects on drug disposition, concentrations of [3H]saquinavir, [3H]methadone, [3H]buprenorphine, and the paracellular marker, [14C]mannitol were measured in plasma, brain, placenta, and fetal samples after i.v. administrations to nonpregnant and pregnant mice. Following i.v. administration, [3H]saquinavir placenta-to-plasma and fetal-to-plasma ratios were significantly greater in late-gestation mice versus mid-gestation. Furthermore, late-gestation mice experienced significant increases in the [3H]saquinavir and [3H]methadone brain-to-plasma ratios 60 min after dosing relative to mid-gestation (p,<,0.05). No significant differences were observed in these tissue-to-plasma ratios for buprenorphine or mannitol. Repeated dosing (three doses, once daily) decreased the differential uptake of [3H]saquinavir in brain but potentiated it in the fetus. These results suggest that differential expression of P-gp and possibly MRP1 contributes to the gestational-induced changes in brain and fetal uptake of saquinavir. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2832,2846, 2009 [source] Clenbuterol increases muscle fiber size and GATA-2 protein in rat skeletal muscle in uteroMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 5 2008Diane Downie Abstract Certain ,2 -adrenoceptor agonists, such as clenbuterol, are known to elicit a muscle-specific anabolism or hypertrophy in both normal and catabolic muscle in a wide variety of species. However, the underlying mechanism(s) of the ,2 -agonist-induced anabolism remains unclear. This study aimed to determine the effects of clenbuterol administration in utero on skeletal muscle and to examine the underlying molecular mechanisms. Pregnant rats were fed clenbuterol (2 mg/kg diet) from Day 4 of gestation (4 dg) until weanling and fetal samples were taken from 13.5, 15.5, 17.5, and 19.5 dg and from 1d neonatal pups. Muscles were analyzed for total DNA, RNA and protein and sections examined morphologically for changes in muscle development. Western and immunohistochemical analyses were performed to identify changes in known myogenic signaling proteins. Clenbuterol increased the size of both fast and slow fibers in utero which was associated with a decreased DNA:protein ratio (28%) and an increased RNA:DNA ratio (36%). Additionally, drug treatment in utero induced a decrease in the fast:slow fiber ratio (38%). These myogenic changes were correlated with an increase in the GATA-2 hypertrophic transcription factor at both 17.5 dg (by 250%) and 19.5 dg (by 40%) in fetuses from clenbuterol treated dams. In addition, drug treatment resulted in increased membrane association of PKC-µ at 17.5 dg (325%) and increased PKC-, cytosolic abundance (40%) and PKC-, membrane abundance at 19.5 dg (250%). These results are the first demonstration that ,2 -agonists such as clenbuterol may act through upregulating the GATA-2 transcription factor and implicate certain PKC isoforms in the drug-induced regulation of skeletal muscle development. Mol. Reprod. Dev. 75: 785,794, 2008. © 2007 Wiley-Liss, Inc. [source] Thrombocytopenia in hydropic fetuses with parvovirus B19 infection: incidence, treatment and correlation with fetal B19 viral loadBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 1 2008TR De Haan Objective, To examine (1) the incidence of fetal thrombocytopenia in hydropic fetuses with congenital B19 virus infection, (2) the effect of intrauterine platelet transfusions and (3) the correlation between fetal B19 viral load and severity of thrombocytopenia. Design, Retrospective analysis of data from prospectively collected fetal blood samples. Setting, Leiden University Medical Centre, the national centre for management of intrauterine fetal disease in the Netherlands. Population, Thirty hydropic fetuses treated with intrauterine red blood cell and platelet transfusions for human B19 virus-induced severe fetal anaemia and thrombocytopenia over a 10-year period. Methods, Fetal blood samples (n= 30) taken before and after intrauterine transfusion were investigated. No cases were excluded, and there was no loss to follow up. Main outcome measures, Parameters recorded were gestational age, experienced fetal movements, gravidity and parity, severity of fetal hydrops, severity of fetal anaemia and thrombocytopenia and megakaryocyte and reticulocyte counts. Survival and procedure-associated complications were documented. Quantitative B19 viral load measurements were performed on all fetal samples. Results, Forty-six percent of all hydropic fetuses showed severe thrombocytopenia. No antenatal intracerebral haemorrhage or procedure-associated bleeding occurred. Overall, survival was 77%. Platelet counts increased following platelet transfusion and decreased significantly following red blood cell transfusion alone. No correlation was found between fetal viral loads and platelet counts. Conclusion, Thrombocytopenia was frequently encountered in fetal B19V infection, but fetal bleeding complications were not noted. Absence of a direct relationship between fetal B19 viral load and platelet counts suggests a temporal dissociation between these findings. Dilutional thrombocytopenia is frequently seen in the fetus following red blood cell transfusion alone. The clinical significance of this phenomenon is unclear. The risk of fluid overload by fetal platelet transfusion in a severely hydropic fetus should be weighed against the low incidence of fetal bleeding complications. 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