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A Delsalle

Publications and source records attributed to A Delsalle.

7 recordsLinked to original sources
PubMed2006

[Evaluation of conventional hemi nested PCR analysis for fetal RHD determination in maternal plasma].

AIMS: The aim of our study was to evaluate the possibility of identifying the fetal RhD status in maternal plasma using conventional hemi nested PCR analysis. SUBJECTS AND METHODS: After informed written consent, 20 mL of peripheral blood were collected in 99 D-negative pregnant women either at an amniocentesis for prenatal diagnosis or at a prenatal checkup. Fetal DNA extracted from 400 microL of maternal plasma was analyzed by two different operators with a hemi-nested PCR extending an area of the RhD gene exon 10. The results were compared to the fetal RhD status obtained by PCR amniotic fluid analysis or blood analysis of newborns after delivery. The influence of mother's and baby's phenotype were also studied. RESULTS: Among the 99 D-negative pregnant women, all Caucasian, 47 were in their second trimester and 52 in their third trimester (mean: 27.20 weeks of gestation +/-8.25). Sixty-nine fetuses were D-positive and thirty D-negative. The sensitivity and specificity of our technique were respectively 100% and 86.7% and 15% of discordant results were observed between the two operators. Four false positives were observed. According to maternal phenotype, a fetal unexpressed RHD gene was suspected in only one case because of a particular fetal phenotype (ddCcEe). CONCLUSION: A conventional hemi nested PCR analysis of maternal plasma could be used for accurate fetal RhD status. However this procedure is difficult to apply for routine analysis because of the importance of anti-contamination measures required to obtain good results. Real time quantitative PCR analysis on fetal DNA is more suitable. Whatever the operating procedure used, polymorphism of RhD gene may follow in either false negative from presence of rearranged gene or false positive from occasional presence of a non functional RHD gene.

DNA↗
PubMed1998

[Identification of alloantibodies associated with an autoantibody: profile of 2 quality control programs in French blood transfusion facilities].

The French Blood Transfusion Society working group Immunohaematology and the French Blood Transfusion Center of Lille performed two quality control exercises-96-01 and 97-02-in order to evaluate identification performances of alloantibodies associated with an autoantibody recognizing a high frequency antigen. Concerning control 96-01, 83 (75%) of the 110 blood transfusion centers participating at this exercise sent results. The alloantibody screening was correct for 78 of them (94%). Sixty-one (78%) blood transfusion centers correctly identified the specificities (anti-RH1 + anti-FY1). Concerning control 97-02, 82 (94%) of the 87 blood transfusion centers participating in this exercise sent results. The alloantibody screening was correct for 69 (88%) of them. Fifty-three blood transfusion centers (77%) correctly identified the specificities (anti-RH3 + anti-FY1). These exercises allowed us to confirm the main procedures used in routine for national scale testing. The analysis of the results has underlined the importance of these tests for assessing the quality of these examinations, and highlighted the means to be carried out in order to improve them.

Antibodies, Anti-Idiotypic↗
PubMed1998

[Fetal cells in the maternal blood: a step towards non-invasive prenatal diagnosis? Review of the literature].

Prenatal diagnosis of genetic abnormalities requires nucleated fetal cells which are currently obtained by invasive techniques such as amniocentesis, chorionic villus sampling and percutaneous umbilical blood sampling. Each of these entails a risk to the foetus and sometimes to the mother. Nucleated fetal cells have been reported to be present in maternal blood. Recovery of fetal cells from maternal blood would allow a noninvasive prenatal diagnosis. Their rarity (1 fetal cell for 10(6) to 10(8) maternal cells) presents a technical challenge. Due to the small number of fetal cells, sensitive analysis techniques such as PCR and FISH are necessary. Some degree of fetal cells enrichment in the maternal blood sample often precedes the analysis. Different techniques are used for the enrichment: discontinuous density gradient, magnetic activated cell sorting, fluorescence activated cell sorting, micromanipulator.... Several prenatal diagnosis have already been performed from maternal venous blood samples: diagnosis of gender, RhD blood genotype, Duchenne muscular dystrophy and hemoglobinopathy by PCR, diagnosis of gender and chromosome aneuploidy by FISH. Many teams are working on this subject. It is difficult to compare the studies because the techniques of enrichment and analysis vary. We review the different strategies chosen for prenatal diagnosis from maternal blood and discuss the results.

Cell Nucleus↗