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BackgroundDespite the non-invasive nature of non-invasive prenatal testing (NIPT), there is still a need for a separate informed consent process before testing. The objectives of this study are to assess (a) knowledge and preferences of Chinese women in a major public hospital in Hong Kong who underwent NIPT, and (b) whether their knowledge and preferences differ depending on womens’ characteristics and sources of information.MethodsSetting: prenatal diagnosis and counselling clinic.Between February 2012 and September 2013, a questionnaire survey was distributed to all women who underwent NIPT after positive aneuploidy screening. As a pilot study, ten knowledge questions were designed based on the rapid response statement on Prenatal Detection of Down Syndrome using Massively Parallel Sequencing from the International Society for Prenatal Diagnosis in 2011. The source of women’s knowledge and their preferences were also evaluated. While conventional screening was publicly funded, NIPT was not. Differences between subgroups were compared using chi square tests and logistic regression analysis.ResultsOf 152 women who underwent NIPT, 135 (88.8 %) completed their questionnaires. More than 90 % of women recognised the possibility of false positive and false negative results. Slightly more than 70 % of women knew the inferior sensitivity of NIPT compared to an invasive test, and the possibility of an uninformative test result, but were not aware of the complicated aspects of NIPT. Pregnant women with an advanced level of education or those who underwent NIPT before 15 weeks provided answers that was more accurate by around 10-20 % in two to three knowledge questions than those without. These associations were confirmed by multivariate logistic regression analysis. The women received information on NIPT largely from their private doctors (47.4 %) and web (41.5 %). In their future pregnancies, more women would opt for NIPT (a self-financed item) after positive screening (‘free’ in a public hospital) (57.8 %) than as a primary screening (30.4 %).ConclusionsIt is feasible to use a questionnaire based on the ISPD statement on NIPT to assess women’s knowledge of the test. The Chinese women who underwent NIPT recognised the limitations, but did not understand the complicated aspects. More information should be provided by health care professionals in order to facilitate an informed choice by patients. More women preferred NIPT as a contingent test than as a primary screening probably because of its high cost.

Objectives: To investigate how the introduction of noninvasive prenatal testing (NIPT) influenced women's testing choices following a positive Down syndrome screening. Methods: A retrospective study was conducted to compare differences in the uptake rates of invasive prenatal diagnosis (IPD) or no testing in one public hospital 1 year before (pre-NIPT) and 1 and 2 years after the introduction of NIPT in private in August 2011 using descriptive analysis and a χ² test. Conventional screening was funded publicly, but NIPT was not. Multivariable binary logistic regression was used to determine factors affecting choices. Results: In pre-NIPT and in years 1 and 2 after the introduction of NIPT, 306, 362 and 401 women who screened positive were seen, respectively. In year 1 and year 2, 12.6 and 26.7% of them underwent NIPT while IPD was decreased by 16.3 and 25.6%, respectively (p < 0.001). Both chorionic villus sampling and amniocentesis decreased in year 1, but only the former in year 2. However, the rate of declining further testing was similar before and after NIPT (p = 0.213). In multivariable analysis, first trimester screening, nulliparity and working women were significant predictors of accepting NIPT, while only nulliparity was a predictor of declining IPD (OR = 0.61). Conclusions: Introduction of NIPT resulted in a significant decrease in IPD for 2 consecutive years.

Hydrops fetalis is commonly due to Hb Bart's (γ4) disease in South East Asia. Here, we report an unusual case of hydrops fetalis due to congenital dyserythropoietic anemia (CDA) associated with compound heterozygosity for Krüppel-like factor 1 (KLF1) gene mutations. Fetal cardiomegaly was first detected on routine mid-trimester scan in a pregnant woman with normal mean corpuscular volume (MCV) and Rhesus positive status. The fetus subsequently developed hydrops fetalis, and cordocentesis showed severe fetal anemia with a hemoglobin (Hb) level of 3.4 g/dL. Common causes of fetal anemia including Hb Bart's disease, parvovirus infection, and red cell antibodies were excluded. In view of the marked increase in erythroblasts at various stages of erythropoiesis, the diagnosis of CDA was suspected. We screened the couple for previously reported KLF1 gene mutations, showing that the mother was heterozygous for the c.525_526insCGGCGCC, p.Gly176Argfs*179 mutation, and her husband heterozygous for c.1012C>A, p.Pro338Thr mutation. The fetus was a compound heterozygote for these two KLF1 mutations. After counseling, repeated intrauterine transfusions were given at 27, 29, and 34 weeks' gestation; the hydrops fetalis was resolved. The baby was delivered at 34 weeks' gestation and required monthly blood transfusions but was otherwise thriving. Bone marrow aspiration at 10 months of age showed the features of ineffective erythropoiesis, compatible with CDA. In conclusion, hydrops fetalis can rarely be due to CDA associated with a compound heterozygous mutation for KLF1 gene mutations, and be managed by repeated intrauterine transfusions. Our present report adds to the wide clinical spectrum of KLF1 mutations.

Among the animal models for studying the molecular basis of atrial and sinoatrial node (SAN) biology and disease, the mouse is a widely used species due to its feasibility for genetic modifications in genes encoding ion channels or calcium handling and signaling proteins in the heart. It is therefore highly valuable to develop robust methodologies for studying SAN and atrial electrophysiological function in this species. Here, we describe a protocol for performing dual calcium-voltage optical mapping on mouse sinoatrial preparation (SAP), in combination with an optogenetic approach, for studying SAP membrane potential, intracellular Ca 2+ transients, and pacemaker activity. The protocol includes the details for preparing the intact SAP, robust tissue dual-dye loading, light-programmed pacing, and high-resolution optical mapping. Our protocol provides an example of use of the combination of optogenetic and optical mapping techniques for investigating SAP membrane potential and intracellular Ca 2+ transients and pacemaker activity with high temporal and spatial resolution in specific cardiac tissues. Thus, our protocol provides a useful tool for studying SAP physiology and pathophysiology in mice.