A phantom study comparing low-dose CT physical image quality from five different CT scanners Yali Li, Yaojun Jiang, Huilong Liu, Xi Yu, Sihui Chen, Duoshan Ma, Jianbo Gao, Yan Wu

Background: Dandy-Walker syndrome (DWS) is a rare congenital malformation of the central nervous system (CNS), characterized by underdevelopment or dysplasia of the cerebellar vermis, expansion of the fourth ventricle and posterior fossa cistern. The incidence is aboutapproximately 1/25000–1/35000. At present, the etiology and pathogenesis of DWS are not completely clear. It is mostly considered to be a multifactorial genetic disease that is related to both genetic factors and environmental factors. There is no large sample size analysis of the chromosomal profile of DWS up to now. This study aims to provide clinical reference for prenatal diagnosis via summarizing the clinical features and pregnancy outcomes of Dandy-Walker syndrome. Methods: A total of 76 cases of foetal Dandy-Walker syndrome out of 19,506 pregnant women underwent cordocentesis or amniocentesis for genetic detection. Rapid prenatal karyotyping, single nucleotide polymorphism array (SNP-array) and BACs-on-Beads™ (BoBs) were performed for prenatal genetic diagnosis. The results of ultrasonography, genetic analysis and pregnancy outcome were recorded. Results: Of the 76 cases, 19 were isolated DWS, while 57 cases were accompanied by other ultrasound-visible abnormalities. Ultrasound abnormalities of the CNS were most frequently observed, accompanied by DWS. Twenty-five out of 76 cases had chromosomal abnormalities, and the rate of chromosomal abnormalities increased in pregnant women of advanced maternal age or in combination with other ultrasound abnormalities. Of the 19 cases in the isolated DWS group, nine pregnant women chose to terminate the pregnancy, while seven cases continued the pregnancy and all infants were normal. Among the 57 pregnant women with pathological ultrasound manifestations other than foetal DWS, 44 chose to terminate the pregnancy, while 12 cases continued the pregnancy. Further follow-up revealed one newborn with postnatal neurodevelopmental delay. A female term neonate presented with very severe sensorineural deafness, and an infant died 7 days after birth with abnormal development of multiple organs. Conclusions: Pregnant women with DWS in foetal ultrasonic examination should be offered a careful and comprehensive foetal ultrasound scan and further prenatal genetic testing including karyotype analysis and SNP-array. The prognosis of the foetus without chromosomal aberration is good in isolated DWS pregnancies but poor in nonisolated DWS pregnancies.

Background: Although assisted reproductive technology (ART) is extensively used in couples with fertility problems, the risk of birth defects among infants conceived with ART is still a concern. Therefore, to more accurately assess the risk of birth defects after ART treatment, we performed a meta-analysis of all available cohort studies relating to birth defects among infants conceived with ART. Methods: We used an established strategy to search the databases of PUBMED, EMBASE, COCHRANE, WEB OF SCIENCE, CNKI, CBM and VIP for studies published between 2008 and 2020. Subgroup analyses and sensitivity analyses were used to examine sources of heterogeneity. Pooled adjusted odds ratios (ORs) were calculated using a fixed effects model. RevMan5.3 was used to draw a forest plot, and Stata14.0 was used to test for publication bias. Results: We included 14 cohort studies from different countries. The infants conceived with ART had a 1.22-fold higher likelihood of birth defects than children born after natural pregnancy(OR = 1.22, 95% CI [1.17, 1.28], P < .05). The prevalence of birth defects after ART treatment was higher in singleton births than in multiple births. In a meta-analysis of data from 6 studies, we found associations between ART and birth defects related to specifics organs: cardiovascular defects, OR = 1.51, 95% CI [1.34–1.69], P < .05; musculoskeletal defects, OR = 1.09, 95% CI [1.03–1.15], P < .05; urogenital defects, OR = 1.24, 95% CI [1.11–1.38], P < .05; central nervous system defects, OR = 1.33, 95% CI [1.14–1.55], P < .05; and orofacial defects, OR = 1.45, 95% CI [1.15–1.83], P < .05. Conclusions: ART treatment does present an increased risk of birth defects. The prevalence of birth defects after ART treatment is lower in multiple births than in singleton births. Further research is required to examine the risks for birth defects after ART treatment.

Non‐methane volatile organic compounds (NMVOCs) have a significant impact on air quality in urban areas. Detecting NMVOCs emission with its proxy HCHO on urban scales from space, however, has been limited by the lack of discernible enhancement. Here we show clear urban HCHO plumes from 16 cities over the globe by rotating TROPOspheric Monitoring Instrument HCHO pixels according to wind directions. We fit the downwind structure of the plumes with the exponentially modified Gaussian approach to quantify urban HCHO effective production rates between 7.0 and 88.5 mol s⁻¹. Our results are in line with total NMVOC emissions from the EDGAR inventory (r = 0.76). Our work offers a new measure of total NMVOC emissions from urban areas and highlights the potential of satellite HCHO data to provide new information for monitoring urban air quality.

Congenital heart disease (CHD) is a heterogeneous collection of structural abnormalities of the heart or great vessels that are present at birth. These birth defects are one of the leading causes of infant mortality and morbidity worldwide. The etiology and pathogenesis of CHD are unclear and largely considered to be multifactorial in nature. Since the chromosomal profile of CHD has not been analyzed in a large sample size, we aimed to summarize the clinical features, cytogenetics findings, and pregnancy outcomes of CHD to provide a clinical reference for prenatal diagnosis. Among 21,152 pregnant women, 471 (2.23%) showed fetal CHD on cordocentesis or amniocentesis. The number of cases showing simple CHD, simple CHD with concomitant extracardiac structural abnormalities, complex CHD, and complex CHD with concomitant extracardiac structural abnormalities was 128, 124, 89, and 130, respectively. For prenatal genetic diagnosis, karyotyping was performed with single-nucleotide polymorphism array(SNP-array)-based chromosomal microarrays, fluorescence in situ hybridization (FISH), copy number variation sequencing (CNV-seq), and BACs-on-Beads™ (BoBs) analyses. The results of ultrasonography examinations, genetic analyses, and pregnancy outcomes were recorded in detail. Ventricular septal defects (VSDs) were observed in 245 (52.02%) cases of fetal CHD. Among the 471 cases of CHD, 258 (54.78%) showed other ultrasound abnormalities. The most common ultrasound abnormalities were abnormalities of the central nervous system. The 471 cases included 93 (19.75%) cases showing chromosomal abnormalities, and the incidence of these abnormalities increased with advanced maternal age or the presence of other ultrasound abnormalities. In eight cases, karyotype analysis showed normal results while SNP-array or CNV-seq results were abnormal. Among the 453 cases that were followed up, 166 (36.64%) involved pregnancy termination, 273 (60.26%) involved live births, 7 (1.55%) involved fetal death in utero, and 7 (1.55%) involved neonatal death after birth. Fetuses with CHD showed higher rates of chromosomal abnormalities. In cases diagnosed with fetal CHD during fetal ultrasonic examination, the mothers should undergo a careful and comprehensive fetal ultrasound scan as well as prenatal genetic testing, including karyotype analysis and SNP-array or CNV-sequencing. The prognosis for simple fetal CHD is good, while the prognosis for complex fetal CHD and extracardiac anomalies is poor.