Prenatal diagnosis of de novo distal 11q deletion associated with sonographic findings of unilateral duplex renal system,pyelectasis and orofacial clefts

In utero diagnosis of de novo distal 11q deletion associated with renal and orofacial malformations has not been previously described. We present a 35-year-old pregnant woman with prenatal sonographic findings of a unilateral duplex renal system, pyelectasis and orofacial clefts at 20 weeks' gestation. Both genetic amniocentesis and postnatal cytogenetic analysis revealed de novo 46,XX,del(11)(q23). After birth, the fetus manifested a dysmorphic phenotype correlated with del(11q) syndrome. Genetic marker analysis showed a paternally derived distal deletion of chromosome 11q and a breakpoint centromeric to D11S1341. The present case represents the earliest prenatal diagnosis of a duplex renal system, pyelectasis and an additional feature of orofacial clefts associated with distal 11q deletion. Prenatal sonographic detection of a duplex renal system, pyelectasis and orofacial clefts should warrant a careful assessment of fetal anatomy and prompt cytogenetic analysis looking for chromosomal aberrations. Copyright © 2001 John Wiley & Sons, Ltd.     

Noninvasive detection of fetal sex: the laboratory diagnostician's view

Toward the end of the twentieth century it was discovered that cell-free fetal DNA sequences could be detected in maternal blood plasma. Initially, Y-chromosome sequences originating from male fetuses were targeted in cell-free DNA extracted from maternal plasma in order to demonstrate proof of this concept towards the development of noninvasive prenatal diagnosis methods. Clinical application of this approach is now possible. Fetal sex can be detected through a procedure that is noninvasive with respect to the fetus. Specifically, the presence of Y-chromosome sequences in maternal blood plasma indicates that the fetus is male, whereas lack of a signal will indicate that the fetus is female. Fetal sex can be detected very early, from at least the 7th week of pregnancy (and even earlier, according to several studies), about two months before this information is available through ultrasound scanning. Although the controversial issue of fetal sexing is not new, it is expected that with the availability of an accurate noninvasive test, public interest will rise. It is therefore imperative that an authorized committee of experts in each country generates an official policy regarding application of the test. Copyright © 2006 John Wiley & Sons, Ltd.     

Amniotic fluid microvillar enzyme activities in the early detection of fetal abnormalities

Measurement of the microvillar enzymes, γ-glutamyltranspeptidase (GGTP), aminopeptidase M (APM) and alkaline phosphatase (ALP), in amniotic fluid supernatant has been proposed as a method for the early prenatal diagnosis of cystic fibrosis. The activities of these enzymes in a series of other fetal abnormalities have now been examined. GGTP activities were below the 5th percentile in 28 out of 54 cases of trisomy 21 and 9 of 14 cases of trisomy 18, while APM values were below this cut-off in 26 of 54 cases of trisomy 21 and 8 of 14 cases of trisomy 18. Abnormal ALP isoenzyme ratios were found in 6 of 54 cases of trisomy 21 and 4 of 14 cases of trisomy 18. If prenatal cytogenetic studies are routinely carried out on amniotic fluid cells, the occasional confounding effect of abnormal microvillar enzymes associated with fetal trisomies rather than with cystic fibrosis should be avoided.     

Improvement of detection method of Cryptosporidium and Giardia in reclaimed water

Cryptosporidium and Giardia are two typical species of pathogenic protozoans that seriously endanger water quality. Previous works indicated that detection of Cryptosporidium and Giardia with modified United States Environmental Protection Agency (USEPA) method-1623 using a membrane filtration-elution for sample concentration attained better recovery and lower cost compared to the USEPA method-1623. Several improvements of membrane filtration-elution step as well as immunomagnetic separation (IMS) steps were investigated and an optimized method for detection of Cryptosporidium and Giardia in wastewater reclamation system was recommended in this paper. The experimental results show that an overnight soak of the membrane after scraping and vortex agitation before elution could enhance and stabilize the recovery. Increasing turbidity to 4 NTU by adding kaolin clay before filtration could effectively improve the recovery of low-turbidity water. Washing the concentrate after centrifugation and twice acid dissociation both reduced the impact of water quality to protozoan recovery. Protozoans in different water samples were determined by this optimized method, and the recovery of Cryptosporidium and Giardia were above 70% and 80% respectively, much higher than the acceptance of method-1623. __________ Translated from Environmental Science, 2006, 27(12): 2547–2552 [译自: 环境科学]     

Transvaginal sonographic detection of skeletal anomalies in the first and early second trimesters

We report the detection of 42 cases of musculoskeletal anomalies routinely screened by transvaginal sonography at 12-16 weeks of gestation out of 7325 examined pregnant women (incidence of 0·57 per cent).     

氧化石墨烯强化厌氧氨氧化菌的脱氮性能

采用氧化石墨烯（GO）增强厌氧氨氧化菌的脱氮性能.通过批次试验观察GO对厌氧氨氧化菌的影响,结果表明：当GO浓度为0.15g/L时,厌氧氨氧化菌脱氮性能最好,总氮去除率比无GO的空白组提高18.6%;当GO剂量达到0.2g/L时,厌氧氨氧化菌活性受到抑制,总氮去除率比空白组降低了26.0%.通过对照实验研究GO对厌氧氨氧化菌脱氮性能的长期影响,结果表明：添加GO的R2反应器在每个基质浓度阶段的平均总氮去除率分别为85.3%,83.2%,81.1%,80.8%,均高于未添加GO的R1反应器.对R2反应器周期内脱氮性能进行动力学分析发现,修正的Boltzmann模型和修正的Gompertz模型比修正的Logistic模型更适合描述GO作用下周期内基质去除特性,并且通过模型得到了周期内任意t时刻下的出水总氮浓度和总氮去除率预测公式.     

Maternal Serum CA 125 for aneuploidy detection in early pregnancy

Maternal serum CA 125 levels were determined at 9–11 menstrual weeks for 26 cases of trisomy 13 (n = 4), trisomy 18 (n = 7), trisomy 21 (n = 15), and appropriate controls. There were no statistically significant differences between groups.     

Improvement of prenatal diagnosis of wilson disease using microsatellite markers

This paper describes a case of prenatal diagnosis for Wilson disease (WD) carried out in an at-risk couple of Sardinian descent, following non-directive genetic counselling. Diagnosis was obtained by using eight microsatellites located within or flanking the WD locus, six of which were 100 per cent and two 50 per cent informative. The use of several markers may limit the occurrence of misdiagnosis resulting from recombination or instability of repeats.     

苏东坡对大自然的科学观

北宋大文豪苏东坡,一生坎坷,官宦沉浮,曾先后任近十个州的地方官,并三度贬谪黄州、惠州和儋州.他虽然是封建时代的士大夫,但对认识自然、利用自然是有建树的.如发现开发徐州煤炭,对庐山地貌特征的认识,夜探石钟山钟声之谜和合理利用水利资源等.     

Transvaginal sonography—detection of findings suggestive of fetal chromosomal anomalies in the first and early second trimesters

Over a 4-year period, 14 dyskaryotic fetuses were diagnosed by amniocentesis, performed after early detection of malformations using transvaginal sonography (TVS). These 14 dyskaryotic fetuses were detected out of 4878 sonographic screenings performed by TVS between 9 and 16 weeks' gestation. Twenty-eight per cent of the referrals were at high risk and 72 per cent were at low risk for fetal malformations. Two hundred and twenty-nine fetuses (4.7 per cent) of the screened population had 265 anomalies, 39 per cent of them being transient. In 7 of the 14 dyskaryotic fetuses (50 per cent), the sonographically detected anomalies were transient, being undetected by follow-up sonographic screenings at later gestational ages (⩾18 weeks). Postponing the first sonographic scan aimed at malformation detection to a later gestational age may lead to transient anomalies and their associated dyskaryosis being missed.     

The significance of early second-trimester sonographic detection of minor fetal renal anomalies

A study of 6350 consecutive transvaginal ultrasound examinations was performed as part of a routine fetal evaluation. Twenty-one cases (0.33 per cent) of early second-trimester sonographic detection of minor renal abnormalities (unilateral renal agenesis, pelvic kidney, and double collecting system) are presented. The sonographic diagnosis was made at 14–18 weeks of pregnancy and confirmed, in all of the 21 fetuses, postnatally or by post-mortem. A high incidence of associated fetal anomalies (24 per cent) and parental renal abnormalities (14 per cent) was demonstrated. Transvaginal sonography was found to be a useful tool for diagnosing these renal anomalies as early as 14 weeks of pregnancy. The likelihood of various associated anomalies and long-term implications on renal function raise questions concerning the prenatal management of such patients.     

Towards real-time detection of wastewater in surface waters using fluorescence spectroscopy

The presence of municipal wastewater at the intake of a major drinking water treatment facility located on Lake Ontario was examined using fluorescence data collected during a period of continuous monitoring. In addition, controlled mixing of lake water and wastewater sampled from a local treatment facility were conducted using a bench-scale fluorescence system to quantify observed changes in natural organic matter. Multivariate linear regression was applied to components derived from parallel factors analysis. The resulting mean absolute error for predicted wastewater level was 0.22% (V/V, wastewater/lake water), indicating that wastewater detection at below 1.0% (V/V) was possible. Analyses of sucralose, a wastewater indicator, were conducted for treated wastewater as well as surface water collected at two intake locations on Lake Ontario. Results suggested minimal wastewater contribution at the drinking water intake. A wastewater detection model using a moving baseline was developed and applied to continuous fluorescence data collected at one of the drinking water intakes, which agreed well with sucralose results. Furthermore, the simulated addition of 1.0% (V/V) of wastewater/wastewater was detectable in 89% of samples analyzed, demonstrating the utility of fluorescence-based wastewater monitoring.