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Objectives: To evaluate the performance of noninvasive prenatal testing by cell-free circulating fetal DNA in maternal blood (cfDNA) in screening for trisomies 21 in twin pregnancies., Methods: CfDNA was performed in 492 patients with twin pregnancies without ultrasound anomalies in the first trimester as a first-line screening test or after serum screening. Data were collected prospectively and a retrospective analysis was done. CfDNA was executed by massive parallel technique. The fetal fraction threshold for test evaluation was 8%. Regression analysis was performed to evaluate the effect of different parameters on the test failure rate. Performance of the test was also considered., Results: In 377 patients, the test was prescribed first line and in 115 after standard serum screening. Twelve tests (2.9%) have initially failed on the 420 pregnancies with available outcomes and regression analysis found only maternal weight as a significant independent factor of test failure. A second test was performed on 10 patients, all of them had an available result. cfDNA identified all 3 cases of trisomy 21. The sensitivity was 100.0% (95% CI [29.2-100.0%]) and specificity was 99.8% (95% CI [98.7-100.0%]). There was no significant difference between spontaneous pregnancies and those induced by assisted reproductive technologies (ART), in terms of fetal fraction percentage, no-call results for cfDNA screening, maternal weight, or test performance between the two groups., Conclusion: In twin pregnancies without fetal ultrasound abnormalities, the performance and success rate of the cfDNA are excellent. Therefore, cfDNA could be offered in routine practice as a first-line screening test in this population., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objectives: To assess the determinants associated with the use of analysis of cell-free DNA in maternal blood for detection of trisomy 21 in high-risk women., Materials and Methods: Prospective study conducted in a single center between July 15, 2014 and December 15, 2014 on 99 consecutive women with increased risk of trisomy 21 above 1/250., Results: Analysis of cell-free DNA in maternal blood for detection of fetal trisomy 21 was proposed to 95 women out of 99, among them, 43 women (45.3%) required the test. Among these 43 women, 17 (38.6%) had a higher socio-economic status versus 10 (19.2%) among the women who did not request the test (P=0.03). The most common reason given by the 52 women who did not request the analysis of cell-free DNA was the cost, for 30 of them (57.7%), then because the test was not providing certainty for the diagnostic of trisomy 21 for 23 women (44.2%)., Conclusion: Analysis of cell-free DNA on maternal blood for detection of trisomy 21 does not seem accepted by the majority of women. The cost is probably the main reason for not using this test, but it seems that the lack of diagnostic certainty is also an obstacle for some women., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objectives: To evaluate de performances of noninvasive prenatal testing using cell free circulating fetal DNA (cffDNA) for the detection of fetal trisomy 21, 18 and 13 in a French population., Materials and Methods: cffDNA analysis was performed by massive parallel sequencing during a multicenter, non interventional, prospective study and the results were compared with a standard fetal karyotype., Results: Results were available for 886 patients who have been classified as high- or moderate-risk depending on the presence of fetal abnormalities on ultrasound examination. For the high-risk group (n=376), the sensitivity and specificity of the test were 100% and 99.9% for trisomy 21, 88% and 99.9% for trisomy 18 and 100% and 99.9% for trisomy 13. The rate of other pathogenic chromosomal abnormalities with a negative NIPT was 7.9%. In the low-risk group (n=510), the sensitivity was 100% and the specificity 99.8% for trisomy 21, and only 0.4% of pathogenic chromosomal abnormalities were revealed by fetal karyotyping but not detected by cffDNA analysis., Conclusion: Noninvasive prenatal testing using cffDNA for high risk patients without fetal anomalies at ultrasound could be recommended in France after counseling on the possible risk of undiagnosed anomalies., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objectives: Congenital Cytomegalovirus (CMV) infection is the main cause of neurological handicap in young children. The objective for studying genetic polymorphism of strains responsible for congenital infection is to identify CMV strains or groups of strains which would be more frequent in this context and/or which would be responsible for more severe congenital infection., Methods: In this paper, we report and analyze the literature concerning the genetic polymorphism of CMV strains responsible of congenital infection, in the genes coding for the envelop protein B and the non structural UL144 protein and in the CMV short tandem repeats., Results and Conclusion: All UL144 and gB genotypes can be vertically transmitted from mothers to fetuses, none of these studies has shown any link between the genotypes and the severity of congenital disease. Moreover, no link between short tandem repeats polymorphism and severity of congenital disease has been demonstrated. However, short tandem repeats analysis may be a powerful tool to study the epidemiology of CMV congenital infections.

Circulating fetal DNA in maternal plasma and serum was first demonstrated by Lo et al. in 1997 and has become a useful tool for prenatal diagnosis less than five years later. There is more and more evidence that the trophoblastic cells act as the major source of this circulating fetal DNA. Contrary to fetal cells analysis in maternal blood which requires isolation and enrichment procedures, fetal DNA analysis is relatively easy to perform with the use of real-time PCR. Non-invasive fetal sex and fetal RHD genotype determination are, to date, the two main clinical indications. Those newly offered possibilities have changed the management of pregnant women who are carriers for X-linked genetic disorders; prenatal diagnosis by choriovillous sampling could only be performed for male fetuses avoiding an unnecessary risk of fetal loss for female fetuses. Moreover, fetal RHD genotyping by maternal blood analysis could be useful in RhD-negative women at risk of immunization in order to adapt prophylactic anti-D injection.

Objective: Couples with a risk of transmitting X-linked diseases included in a preimplantation genetic diagnosis (PGD) center need early and rapid fetal sex determination during pregnancy in two situations. The first situation corresponds to control of embryo sexing after PGD, the second one being that of couples in PGD program having a spontaneous pregnancy. Determination of fetal sex can be achieved by karyotyping using invasive procedures such as chorionic villus sampling (CVS), amniocentesis or cordocentesis and by non-invasive procedures such as ultrasound (US) examination. CVS is the earliest invasive procedure for fetal sex determination and molecular analysis of X-linked genetic disorders during the first trimester but it is associated with a risk of fetal loss. US allows reliable fetal sex determination only during the second trimester. Recently, reliable non-invasive fetal sex determination was realized by using SRY gene amplification in maternal serum., Patients and Methods: We report the prospective use of fetal sex determination in maternal serum in our PGD center. Management of pregnancies was performed using this non-invasive procedure in four cases of embryo sexing control and nine cases of spontaneous pregnancies in couples included in PGD program for X-linked diseases., Results: Fetal sex results using SRY gene amplification on maternal serum were in complete concordance with fetal sex observed by cytogenetic analysis or US examination, as well as at birth., Discussion and Conclusion: This new strategy allowed rapid sex determination during the first trimester and permitted to avoid performing invasive procedures in nine pregnancies.

The presence of free fetal DNA circulating in the maternal plasma or serum has been demonstrated by Lo et al. in 1997. In 2002, fetal DNA has been used as a tool for prenatal diagnosis. The main indications for this technique are currently limited to determination of fetal sex for X-linked diseases as well as determination of fetal RhD in RhD negative women. Other more exceptional applications are also possible, including detection of translocations or search for de novo point mutations but currently remain in the research phase.

Objective: Fetal sex prediction can be achieved using PCR targeted at the SRY gene by analyzing cell-free fetal DNA in maternal serum. Unfortunately, the results reported to date, show lack of sensitivity, especially in the first trimester of pregnancy. Therefore, determination of fetal sex by maternal serum analysis can not replace caryotype analysis following chorionic villus sampling., Patients and Methods: A new highly sensitive real-time PCR was developed to detect a SRY gene sequence in maternal serum. Analysis was performed on 121 pregnant women during their first trimester of pregnancy (mean gestational age: 11.8 weeks). Among them, 61 had at least one previous male-bearing pregnancy. Results were compared to fetal sex., Results: SRY PCR analysis of maternal serum was in complete concordance with fetal sex. Among the 121 pregnant women, 61 were bearing a male fetus and 60 a female fetus No false negative results were observed. Furthermore, no false positive results results occurred although 27 women carried female fetus during the current pregnancy, had at least one previous male-bearing pregnancy., Discussion and Conclusion: This study demonstrates that a reliable, non-invasive sex determination can be achieved by PCR analysis of maternal serum during the first trimester of pregnancy. This non-invasive approach for fetal sex prediction should have great implications in the management of pregnant women carriers of an X-linked genetic disorder. Prenatal diagnosis is thus performed for male fetuses only, avoiding invasive procedures and the risk of fetal loss for female fetuses.

Parasitic protozoa have been entrapped within sol-gel silica matrices. Stationary phase promastigote cells of Leishmania donovani infantum are mixed with a silicon alkoxide solution. They remain trapped within the growing oxide network formed upon hydrolysis and condensation of the alkoxide. Electron microscopy shows the preservation of the cellular organization and the integrity of the plasma membrane of entrapped parasites. Specific antigen-antibody reactions have been performed within the sol-gel matrix via enzyme-linked immunosorbent assays (ELISA) currently used for the diagnostic of visceral leishmaniasis. A clear-cut difference in optical density was measured between positive and negative sera from dogs. Entrapped protozoa antigens are still able to react with specific antibodies through the open porosity of the silica network. These results suggest that sol-gel matrices could be used for the development of immunodiagnostic assays requiring whole cell parasites as antigens.

Effects of an extract from Y. enterocolitica 0:3 biotype 4 on mouse splenocytes and human lymphocytes cultures were examined. Low doses had a mitogenic action on splenocytes, while high doses inhibited tritiated thymidine incorporation into the cells. With human lymphocytes only inhibitory effect was observed.

The authors report on 145 cases treated surgically for chronic pancreatitis. 128 cases were operated on principle for association of pain and weight loss, 17 cases under necessity for complications. Surgical procedures were most often pancreatico-duodenectomies (75 cases), left pancreatectomies (34 cases) or rarely total pancreatectomies (4 cases), more rarely wirsungo-jejunostomies (32 cases). Choice of surgical procedures were based on anatomical and clinical arguments, but mainly on E.R.C.P. Post-operative mortality, was 8.2% after pancreatic resections and 3.7 after pancreatico-jejunostomies. Secondary mortality were respectively 13% and 11.5%. The overall mortality was 21% after resection and 15% after drainage. Late fonctional results (after 5 years) were in favour of resection (good results 51%). After drainage (good results 22%) initial good results deteriored with time.

A 21-year-old man presented with a 10-year history of a malabsorption syndrome of moderate severity, splenomegaly, and recurrent respiratory infections. Investigations revealed total atrophy of the villi and primary agammaglobulinemia. A gluten-free diet was ineffective. In spite of the absence of lambliasis, treatment with metronidazole produced objective clinical improvement and biological signs of healing of the malabsorption syndrome, but no alteration in the agammaglobulinemia. The authors discuss the relationship between total villous atrophy and primary agammaglobulinemias and the mode of action of metronidazole.