AES chemunex ADIAFOOD detection system for Listeria spp. environmental sample testing.

The ADIAFOOD Detection System for the detection of Listeria species from environmental surfaces is based on real-time PCR technology and allows rapid pathogen detection within 21 h. The strength of the ADIAFOOD technology resides in its ability to rapidly and accurately detect Listeria species present on surfaces, such as stainless steel, plastic, ceramic, and sealed concrete. The technology is easy to use and versatile.

Nuchal translucency thresholds in prenatal screening for Down syndrome and trisomy 18.

OBJECTIVE: To determine if nuchal translucency (NT) can be used as a first trimester triage marker in prenatal screening for Down syndrome and trisomy 18. METHODS: Data from first trimester prenatal screening in 77 443 women were stratified by maternal and gestational ages. They were then analyzed to identify NT thresholds above or below which only positive (high-risk) or negative (low-risk) results were reported by a first trimester prenatal screening test combining PAPP-A, free beta-hCG and NT. RESULTS: Combined prenatal screening was always positive for Down syndrome when NT thickness exceeded 4.0 mm. As women aged, this upper NT threshold value changed according to gestational age. In women aged 35 to 37 years, combined prenatal screening was always positive when NT exceeded 2.8 mm, 3.0 mm, and 3.4 mm at 11, 12, and 13 weeks of gestation, respectively. In women over 42 years of age, the upper threshold value for NT was 1.8 mm, 2.4 mm, and 2.7 mm at 11, 12, and 13 weeks of gestation, respectively. In women less than 35 years of age, we identified lower threshold values below which combined prenatal screening for Down syndrome was always negative. CONCLUSION: In prenatal screening for Down syndrome and trisomy 18, it is possible to identify NT threshold values above which biochemical screening provides no additional benefit. In pregnancies in which NT is above the established upper cut-offs, invasive prenatal screening can be offered without delay.

Effect of maternal smoking on prenatal screening for Down syndrome and trisomy 18 in the first trimester of pregnancy.

OBJECTIVES: To assess the impact of maternal smoking on first-trimester prenatal screening results for Down syndrome and trisomy 18. METHODS: Data on maternal smoking status, maternal age, gestational dating, levels of free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein A (PAPP-A) in maternal blood and fetal nuchal translucency (NT) thickness were analyzed from a cohort of 53 114 women. Statistical analyses were carried out for crude and adjusted comparisons between smoking and nonsmoking groups. RESULTS: In women who smoked during the first trimester of pregnancy, PAPP-A and free beta-hCG levels from dried blood were significantly decreased (p < 0.001) and fetal NT thickness was significantly increased (p < 0.001). For an overall risk assessment combining maternal age and biochemical and ultrasound markers, no significant changes for Down syndrome were found with smoking, but significant increases in average risk as well as in positive rates were found for trisomy 18 (p < 0.001). A potential association between maternal smoking and trisomy 18 remains to be clarified. CONCLUSION: Adjustment for smoking is recommended in first-trimester prenatal screening for trisomy 18 and probably not warranted for Down syndrome because of the cancelling effects of decreased free beta-hCG and increased NT. Further research is required to demonstrate a biological association between maternal smoking and trisomy 18.