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The structure of the choroid plexus was studied in five normal human embryos, three normal fetuses and three fetuses with choroid plexus cysts. These were detected by ultrasound and the fetuses were karyotypically normal. The choroid plexus appears in the lateral cerebral ventricles at the seventh developmental week. The early structure is lobulated with vessels running in the mesenchymal stroma and forming capillary nets under the single-layered ependymal epithelium. This embryonal structure is converted into the fetal type during the ninth developmental week as the embryonal capillary net is replaced by elongated loops of wavy capillaries that lie under regular longitudinal epithelial folds. The choroid plexus cysts exhibited accumulation of fluid within distended mesenchymal stroma and did not show the wavy folds on this surface, which was smooth. Within this connective tissue of the cyst wall were distended angiomatous interconnecting thin-walled capillaries. Therefore, filled cavities were not lined by any epithelium. We suggest that fetal choroid plexuses cysts (at least in many cases) are in fact pseudocysts exhibiting angiomatous patterns of capillaries in their walls. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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A case is described of the prenatal diagnosis of choroid plexus cysts at 17 weeks' gestation which persisted beyond 36 weeks but could not be detected after delivery. At birth the child was found to have trisomy 18. 相似文献
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Cysts of the choroid plexus of the lateral ventricle can be detected in the fetus during routine scanning at 16–18 weeks' gestation with an approximate incident of one in every 120 pregnancies. It is likely that in a high percentage of cases cysts are bilateral and that their recent discovery is mainly due to improvements in imaging technology. Although the great majority of cases resolve and do not result in any morbidity, five cases of trisomy 18 and one case of trisomy 21 associated with fetal choroid plexus cysts have been reported. In this prospective study, choroid plexus cysts were detected in 42 fetuses, resulting in 40 normal infants and 2 cases of trisomy 18. It is concluded that there may be a relationship between fetal choroid plexus cysts and trisomy 18. In order to obtain a more precise and accurate result, a multi-centre prospective study is being organized. 相似文献
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Katarina Michalcova Shubhadeep Roychoudhury Marek Halenar Eva Tvrda Eva Kovacikova Jaromir Vasicek 《Journal of environmental science and health. Part. B》2013,48(9):752-757
AbstractIsoquercitrin is a dietary bioflavonoid used as a food supplement. We studied the mechanism underlying its effect in human ovarian cancer cells using OVCAR-3 cell line. Viability, survival, apoptosis, release of human transforming growth factor-β1 (TGF-β1) and TGF-β1 receptor, and intracellular reactive oxygen species (ROS) generation by OVCAR-3 cells were examined after isoquercitrin treatment at concentrations 5, 10, 25, 50, and 100?μg mL?1. AlamarBlue assay revealed that isoquercitrin did not cause any significant change (P?>?0.05) in cell viability as compared to control. Apoptotic assay using flow cytometry did not find any significant change (P?>?0.05) in the proportion of live, dead and apoptotic cells as compared to control. ELISA also showed that the release of human TGF-β1 and TGF-β1 receptor were not significantly (P?>?0.05) affected by isoquercitrin as compared to control. Chemiluminescence assay demonstrated that lower concentrations (5, 10, and 25?μg mL?1) were able to exhibit beneficial effects by inhibiting the generation of intracellular ROS. In contrast, elevated concentrations of 50 and 100?μg mL?1 led to oxidative stress (P?0.05). We concluded that the beneficial effect of isoquercitrin on ovarian cancer cells may be mediated by an antioxidative pathway that involves inhibition of intracellular ROS generation, thereby limiting oxidative stress. 相似文献
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An annual quarterly survey of six stations in Yantian Port, Shenzhen, China was conducted from January 2020 to October 2020 to investigate the spatial and temporal distribution of dinoflagellate cysts in the surface sediment of Yantian Port. In total, 36 species representing five groups and two uncertain taxa were identified. The dominant species were Scrippsiella trochoidea, Alexandrium spp., Gymnodinium catenatum, Cochlodinium spp., and Lingulodinium polyedrum. The seasonal difference was not obvious in terms of temporal distribution. The number of species ranged from 32 to 36, and the abundance varied from 297 to 996 cysts/g. The annual average values of the diversity index, richness index, and evenness index were 3.65, 1.55, and 0.93, respectively. The annual number and abundance of heterotrophic species were higher than those of autotrophic species. The number and abundance of species at stations near the dock zone were lower than those near the adjacent area. Notably, six toxic dinoflagellate cysts were found in the surface sediment of Yantian Port, indicating a potential outbreak risk for their vegetative cells in the local coastal area. This study provides a picture of the “Seed Bank” of dinoflagellates near Yantian Port, Shenzhen, and provides a reference value for predicting the occurrence of algal blooms. © 2022 Science Press. All rights reserved. 相似文献
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Xiaoqing Ye Wuye Pan Chunming Li Xiaochen M Shanshan Yin Jianhong Zhou Jing Liu 《环境科学学报(英文版)》2020,32(5):1-9
Polycyclic aromatic hydrocarbons (PAHs) are a typical class of persistent organic pollutants that is ubiquitous worldwide. Previous animal studies suggested that PAHs had adverse effects on female reproduction. However, the human data regarding relationship of PAHs exposure with women reproductive health, such as ovarian dysfunction, are scarce. In this case-control study, the associations of serum levels of PAHs with the risk of premature ovarian failure (POF) and reproductive hormones in Chinese women were investigated, with recruiting 157 POF patients and 217 healthy women. The serum levels of 12 types of PAHs, as well as reproductive hormones, including follicle-stimulating hormone, luteinizing hormone and anti-mullerian hormone, were determined. In the logistic regression models, most individual PAH congeners showed significantly positive correlations with the risk of POF (p < 0.05), except for fluorine and pyrene. Benzo(a)pyrene (BaP), as the most carcinogenic PAH congener, was observed to be significantly positively associated with the risk of POF. After adjustment for age, body mass index, educational levels and household income, per one-unit increase in the log-transformed BaP concentration was significantly correlated with 2.191-fold increased risk of POF (OR = 2.191, 95%CI: 1.634–2.938, p < 0.05). To the best of our knowledge, this is the first study to report an association between internal exposure levels of PAHs and the increased risk of POF in women. 相似文献
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This paper examines the association between fetal choroid plexus cysts (CPCs) and trisomy 18 and proposes a method by which risks can be derived taking into account both sonographic findings and maternal age. Data from our centre on the sonographic findings of 58 fetuses with trisomy 18 and 387 fetuses with CPCs as well as data from published series were used. It was calculated that the prevalence of CPCs in the general population is approximately 1 per cent and at mid-gestation the incidence of CPCs in fetuses with trisomy 18 is approximately 50 per cent. In the 387 fetuses with CPCs, the incidence of trisomy 18 increased with maternal age and the likelihood ratio for trisomy 18 increased with the number of additional abnormalities, from 0·03 for those with isolated CPCs to 0·4 if there was one additional abnormality and 20·5 if there were two or more additional abnormalities. It was concluded that if the cysts are apparently isolated, the risk for trisomy 18 is only marginally increased and maternal age should be the main factor in deciding whether or not to offer fetal karyotyping. If one additional abnormality is found, the maternal age-related risk is increased, so that even for a 20-year-old the risk for trisomy 18 is at least as high as the risk for trisomy 21 in a 35-year-old. In this respect, it may be considered desirable to offer such patients the option of karyotyping. 相似文献