Chorionic villus sampling utilization following reports of a possible association with fetal limb defects

Prenatal diagnosis choices were reviewed in 473 women who presented for genetic counselling prior to 11 weeks' gestation for the indication of advanced maternal age. Group A consisted of 336 patients who were unaware of a possible association between chorionic villus sampling (CVS) and limb defects. Group B consisted of 137 patients who were provided this information. Fifty-one per cent of patients in group A and 45 per cent of patients in group B chose CVS. This difference was not significant by χ² analysis (P = 0·7). Patterns of prenatal diagnosis procedure utilization from 1987 to 1992 revealed a significant reduction in CVS utilization accompanied by a corresponding increase in amniocentesis after the association between CVS and limb defects was publicized. Referrals for CVS counselling also significantly declined. However, acceptance rates did not change for those patients who received genetic counselling. First-trimester genetic counselling, including a discussion regarding a possible association between CVS and limb defects, helps patients make informed decisions concerning prenatal diagnosis options, and, in our population, resulted in no change in CVS acceptance rates.     

Cu/盘状ZnO模型催化剂催化CO2加氢反应中生成CO的活性位研究

通过水热法合成盘状ZnO,并在其表面负载Cu得到Cu/盘状ZnO模型催化剂,将不同气氛下(5%CO/Ar、2.5%H_2/2.5%CO/Ar、5%H_2/Ar,分别记为CZ-5CO、CZ-2.5H_2-2.5CO、CZ-5H_2)还原的模型催化剂用于逆水煤气变换反应.对催化剂进行热重分析(TGA)、X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、原位紫外拉曼光谱(in situ UV-Raman)表征.结果表明,不同的还原气氛可得到不同尺寸的Cu颗粒及不同缺陷浓度的Cu-ZnO界面.CO_2程序升温脱附(CO_2-TPD)结果表明,不同的Cu-ZnO界面具有不同的CO_2活化能力.其中CZ-5H_2形成的Cu-ZnO界面对CO_2活化能力最强,表现出最佳的逆水煤气变换反应活性;CZ-5CO具有更多的表面缺陷可能是由于存在Cu_3Zn合金,但Cu-ZnO界面上CO_2的吸附容量降低,导致逆水煤气变换反应活性低;CZ-2.5H_2-2.5CO的活性介于CZ-5H_2与CZ-5CO之间,界面对CO_2的活化量也介于两者之间.     

The synaptic membrane D2-protein in amniotic fluid from pregnancies with fetal neural tube defects

The D2-protein is a neuronal membrane protein which has an immunochemically detectable soluble derivative in cerebrospinal fluid. We used rocket-on-line immunoelectrophoresis with an antiserum against rat synaptosomal membranes for demonstration of the human D2-protein in fetal cerebrospinal fluid and in amniotic fluids from pregnancies with fetal neural tube defects. D2 was neither found in normal amniotic fluids nor in cases of amniotic fluids from pregnancies with other malformations. Analysis of D2 in amniotic fluids may thus have a future role in the antenatal diagnosis of fetal neural tube defects.     

Prenatal ultrasound diagnosis of amelia

Amelia is a very rare form of limb reduction defect. The incidence of isolated amelia with or without other limb reductions is 0.4 per 100 000 births. We report a cluster of three cases diagnosed prenatally. One was isolated tri-amelia and two were isolated tetra-amelia.     

False-positive amniotic fluid acetylcholinesterase analysis in the third trimester

Thirty-two third-trimester amniotic fluid samples were studied according to the indication for amniocentesis, result of acetylcholinesterase (AChE) analysis, and outcome, in order to address the issue of the effectiveness of AChE testing late in gestation. The results indicate that third-trimester AChE analysis is less effective than second trimester in distinguishing open neural tube defects (ONTDs) and ventral wall defects (VWDs) from other abnormalities. False-positive results occurred in cases of isolated hydrocephaly (four of seven cases), polyhydramnios, and intrauterine growth retardation (IUGR). Caution is recommended in interpreting third-trimester AChE tests, particularly when neither an ONTD nor a VWD is observed by ultrasound.     

Competitive role of nitrogen functionalities of N doped GO and sensitizing effect of Bi2O3 QDs on TiO2 for water remediation

The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots (BQDs) doped TiO₂ with nitrogen doped graphene oxide (NGO) nanocomposite (NGO/BQDs-TiO₂) was fabricated. It was used for degradation of organic pollutants like 2,4-dichlorophenol (2,4-DCP) and stable dyes, i.e. Rhodamine B and Congo Red. X-ray diffraction (XRD) profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal structure. The characteristic diffraction peaks of TiO₂ and its composites showed crystalline anatase TiO₂. Morphological images represent spherical shaped TiO₂ evenly covered with BQDs spread on NGO sheet. The surface linkages of $\text{NO}?\mathrm{O}?\text{Ti}$, $\mathrm{C}?\mathrm{O}?\text{Ti}$, $\mathrm{B}\mathrm{i}?\mathrm{O}?\text{Ti}$ and vibrational modes are observed by Fourier transform infrared spectroscopy (FTIR) and Raman studies. BQDs and NGO modified TiO₂ results into red shifting in visible region as studied in diffused reflectance spectroscopy (DRS). NGO and BQDs in TiO₂ are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence (PL) intensities. X-ray photoelectron spectroscopy (XPS) shows that no peak related to $\mathrm{C}?\mathrm{O}$ in NGO/BQDs-TiO₂ is observed. This indicated that doping of nitrogen into GO has reduced some oxygen functional groups. Nitrogen functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic pollutants. Intermediate byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography (HPLC). Study of radical scavengers indicated that ${\mathrm{O}}_2^{·?}$ has significant role for degradation of 2,4-DCP. Our investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions.