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排序方式: 共有208条查询结果,搜索用时 703 毫秒
1.
David L. Skidmore Aditya P. Pai Ants Toi Leslie Steele David Chitayat 《黑龙江环境通报》2003,23(12):1009-1013
Two de novo cases with Apert Syndrome detected prenatally are presented herein. In the first, fetal ultrasound findings of syndactyly of the hands, craniosynostosis and proptosis resulted in a prenatal diagnosis in the nineteenth week of gestation. This is the earliest prenatal diagnosis of this syndrome in a not-at-risk case. Following counseling, this pregnancy was terminated and subsequent pathological examination and DNA analysis confirmed the diagnosis of Apert Syndrome and coarctation of the aorta. In the second case, fetal ultrasound at 21 weeks' gestation revealed a hypoplastic left heart and clover-leaf skull. Following counseling, this pregnancy was also terminated. Further examination of the fetus and DNA analysis led to a diagnosis of Apert Syndrome. These cases emphasize the need to complete a thorough fetal ultrasound in cases with potentially lethal cardiac abnormality and the importance of incorporating a fetal pathologist, as well as a medical geneticist, in the investigations performed after delivery or pregnancy termination when a fetal abnormality is detected on ultrasound. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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3.
Diana W. Bianchi MD Gretchen K. Zickwolf Melissa C. Yih Alan F. Flint Ossie H. Geifman Marlena S. Erikson John M. Williams 《黑龙江环境通报》1993,13(4):293-300
Fetal nucleated erythrocytes (NRBC) in maternal blood are a non-invasive source of fetal DNA for prenatal genetic screening. We compared the effectiveness of three monoclonal antibodies for the separation of fetal cells from maternal blood by flow sorting. Mononuclear blood cells from 49 healthy pregnant women were incubated with antibody to CD 71, CD 36, and/or glycophorin A (GPA), employed singly or in combination with each other. These monoclonal antibodies recognize surface antigens on haematopoietic precursor cells. Successful isolation of fetal cells was defined as detection of Y chromosomal sequences in maternal blood from women carrying male fetuses, with absence of Y sequences when female fetuses were carried. Thus, gender prediction accuracy was used as a measure of fetal cell separation. Using anti-CD 71 to isolate fetal cells, gender prediction was 57 per cent correct; with anti-CD 36, it was 88 per cent correct. Anti-GPA, an erythrocyte-specific antigen, used alone or in combination with anti-CD 71 or 36, improved gender prediction to 100 per cent. We conclude that antibody to GPA improves the retrieval of fetal NRBC from maternal blood, permitting genetic analysis by the polymerase chain reaction. 相似文献
4.
Qinqin Lou Yinfeng Zhang Dongkai Ren Haiming Xu Yaxian Zhao Zhanfen Qin Wuji Wei 《环境科学学报(英文版)》2014,26(10):2084-2094
Considering some advantages of Rana nigromaculata as an experimental species, we propose that this species, like Xenopus laevis, could be used to assay thyroid hormone(TH) signaling disrupting actions. To validate the utilizability of R. nigromaculata, we investigated the responsiveness of R. nigromaculata to a TH receptor(TR) agonist(T3) and antagonist(amiodarone) by analyzing expression, based on characterizing TR cDNA and developmental expression patterns. With high levels of identity with the corresponding genes in X. laevis, both TRα and TRβ in R. nigromaculata exhibited roughly similar developmental expression patterns to those of X. laevis, in spite of some species-specific differences. Both TRα and TRβ expression had greater changes in the liver and intestine than in the tail and brain during metamorphosis. T3 exposure for 2 days induced more dramatic increases of TRβ expression in stage 27 than in stage34 tadpoles but not in stage 42 tadpoles, showing that the responsiveness of R. nigromaculata to TH decreased with development and disappeared at the onset of metamorphic climax.Corresponding to greater changes of TRβ expression in the liver and intestine than in the tail and brain during metamorphosis, the liver and intestine had higher responsiveness to exogenous T3 than the tail and brain. Amiodarone inhibited T3-induced TRβ expression. Our results show that R. nigromaculata can be used as a model species for assaying TH signaling disrupting actions by analyzing TRβ expression, and intestine tissues at stage 27 are ideal test materials due to high responsiveness and easy accessibility. 相似文献
5.
This study investigated the performance of lab-scale sequencing batch reactors (SBRs) that were inoculated with nitrifying activated sludge and bioaugmented with a Sphingomonas strain KC8 (a 17β-estradiol-degrading bacterium). The bioaugmented SBRs were supplied with synthetic wastewater (average initial total organic carbon (TOC) = 175 mg L−1 and average initial ammonia-N = 25 mg L−1) and daily dose of 17β-estradiol (1 mg L−1) and operated under three solid retention times (SRTs) of 5, 10, and 20 d. After three times periods of the operating SRTs, the overall removal of TOC (>87%) and ammonia (>91%) was similar in all the SBRs. Higher 17β-estradiol removals (>99%) were observed for the SBRs. Neither estrogens nor estrogenic activity was detected in the treated water, except some samples from the SBR operating under 5 d of SRT. The ratios of known estrogen degraders (Sphingomonas strain KC8 and ammonia-oxidizing bacteria) and amoA gene to the total bacterial population decreased as SRT increased, suggesting the presence of unknown estrogen-degraders in SBRs operating at SRT = 10 and 20 d. Real-time-terminal-restriction fragment length polymorphism analysis showed that the evenness of microbial community structures was not affected by the SRT; while, the diversity indices suggest that longer SRTs might lead to more diverse microbial community structure. Overall, the results suggested that bioaugmented bioreactors operating at long SRTs (10 and 20 d) were effective in removing 17β-estradiol to the non-estrogenic treatment endpoint. 相似文献
6.
Wölz J Grosshans K Streck G Schulze T Rastall A Erdinger L Brack W Fleig M Kühlers D Braunbeck T Hollert H 《Chemosphere》2011,85(5):717-723
Bankside groundwater is widely used as drinking water resource and, therefore, contamination has to be avoided. In the European Union groundwater protection is explicit subject to Water Framework Directive. While groundwater pollution may originate from different sources, this study investigated on impacts via flood events.Groundwater was sampled with increasing distance to the river Rhine near Karlsruhe, Germany. Samples were HPLC-MS-MS analyzed for the river contaminant carbamazepine to indicate river water infiltration, giving permanent presence in 250 m distance to the river (14-47 μg L−1). Following a flood event, concentrations of about 16-20 μg L−1 could also be detected in a distance of 750 m to the river. Furthermore, estrogenic activity as determined with the Yeast Estrogen Screen assay was determined to increase up to a 17β-ethinylestradiol equivalent concentration (E-EQ) = 2.9 ng L−1 near the river, while activity was initially measured following the flood with up to E-EQ = 2.6 ng L−1 in 750 m distance. Detections were delayed with increasing distance to the river indicating river water expansion into the aquifer.Flood suspended matter and floodplain soil were fractionated and analyzed for estrogenic activity in parallel giving up to 1.4 ng g−1 and up to 0.7 ng g−1, respectively. Target analysis focusing on known estrogenic active substances only explained <1% of measured activities.Nevertheless, river water infiltration was shown deep into bankside groundwater, thus, impacting groundwater quality. Therefore, flood events have to be in the focus when aiming for groundwater and drinking water protection as well as for implementation of Water Framework Directive. 相似文献
7.
The protective effect of hydroxytyrosol (HT), a strong antioxidant compound from extra virgin olive oil, against TCDD induced toxicity was investigated in human peripheral blood mononuclear cells (PBMC). PBMC (1 × 106 cells mL−1) were divided into four groups and were incubated in a CO2 incubator (5% CO2) for 12 h with vehicle, TCDD (10 nM), TCDD + HT (10 nM + 100 μM) and HT alone (100 μM) respectively. To clarify the role of HT against TCDD induced cytotoxicity, oxidative stress and the levels of antioxidant enzymes were assessed. Incubation of PBMC with TCDD significantly decreased cell viability, catalase (CAT) and glutathione peroxidase (GPx) and increased the levels of superoxide dismutase (SOD), glutathione reductase (GR) and oxidative stress markers such as lipid peroxidation products (LPO), protein carbonyl content (PCC) and reactive oxygen species (ROS). Whereas, HT had an effective antioxidant property as observed by the increased cell viability, normalization of antioxidant enzymes and decreased levels of LPO, PCC and ROS in PBMC co-treated with HT and TCDD. Apoptosis detection and comet assay results shows that HT, by acting as an antioxidant, prevents the damage to DNA induced by TCDD. In addition light microscopic and histopathological observations revealed that the cells are apoptotic and degenerated during TCDD treatment, whereas cells showed intact morphology during co-treatment with HT. On the whole, the results reveal that HT exerts a promising antioxidant potential in protecting the PBMC against TCDD induced oxidative stress, which might be due to the presence of catechol moiety in its structure. 相似文献
8.
Shi W Wang X Hu G Hao Y Zhang X Liu H Wei S Wang X Yu H 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):441-448
Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived l-3,5,3′-triiodothyronine (T3) equivalents (T3-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T3/L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 μg/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River. 相似文献
9.
Robert Kase Peter D. Hansen Birgit Fischer Werner Manz Peter Heininger Georg Reifferscheid 《Environmental science and pollution research international》2009,16(1):54-64
Background, aim, and scope The enzyme-linked receptor assay (ELRA) detects estrogenic and anti-estrogenic effects at the molecular level of receptor
binding and is a useful tool for the integrative assessment of ecotoxicological potentials caused by hormonally active agents
(HAA) and endocrine disrupting compounds (EDC). The main advantage of the ELRA is its high sample throughput and its robustness
against cytotoxicity and microbial contamination. After a methodological adaptation to salinity of the ELRA, according to
the first part of this study, which increased its salinity tolerance and sensitivity for 17-β-estradiol, the optimised ELRA
was used to investigate 13 native sediments characterised by different levels of salinity and chemical contamination. The
applicability of the ELRA for routine analysis in environmental assessment was evaluated. Salinity is often a critical factor
for bioassays in ecotoxicological sediment assessment. Therefore, salinity of the samples was additionally adjusted to different
levels to characterise its influence on elution and binding processes of receptor-binding substances.
Materials and methods The ELRA was carried out with the human estrogen receptor α (ER) in a 96-well microplate format using the experimental setup
known from the competitive immunoassay based on ligand–protein interaction. It is an important improvement that a physiologically
relevant receptor was used as a linking protein instead of an antibody. The microplates were coated with a 17-β-estradiol-BSA
conjugate, and dilution series of estradiol and of native sediment samples were added and incubated with the ER. After a washing
step, a biotinylated mouse anti-ER antibody was added to each well. Receptor binding to estradiol, agonistic and antagonistic
receptor binding, were determined by a streptavidin-POD-biotin complex with subsequent measurement of the peroxidase activity
at the wavelength of 450 nm using a commercial ELISA multiplate reader. The sediment elutriates and pore water samples of
sediments were tested in a dilution series to evaluate at which dilution step the receptor-binding potential ends. In the
elution process (see Section 2.1 to 2.2), a method was developed to adjust the salinity to the levels of the reference testings, which offers an appropriate option
to adjust the salinity in both directions. Statistical evaluation was made with a combination of the Mann–Whitney U test and the pT-method.
Results This part of the study characterised the environmental factor ‘salinity’ for prospective applications of the ELRA. Using reference
substances such as 17-β-estradiol, the ELRA showed sigmoid concentration-effect relations over a broad range from 0.05 μg/l
to 100 μg/l under physiological conditions. After methodological optimisation, both sensitivity and tolerance of the assay
against salinity could be significantly raised, and the ELRA became applicable under salinity conditions up to concentrations
of 20.5‰. The mean relative inter-test error (n = 3) was around 11% with reference substances and below 5% for single sediments elutriates in three replicates each. For
sediment testings, the pore water and different salinity-adjusted elutriates of 13 sediments were used. A clear differentiation
of the receptor-binding potential could be reached by application of the pT-method. Thereby, pT-values from one to six could
be assigned to the sediments, and the deviation caused by the different salinity conditions was one pT-value. The mean standard
deviation in the salinity adaptation procedure of the elutriates was below 5%.
Discussion Although the ELRA has already been used for assessments of wastewater, sludge and soil, its applicability for samples to different
salinity levels has not been investigated so far. Even if the ELRA is not as sensitive as the E-screen or the YES-assay, with
regard to reference substances like 17-β-estradiol, it is a very useful tool for pre-screening, because it is able to integrate
both estrogenic as well as anti-estrogenic receptor-binding effects. According to the results of sediment testing, and given
the integrative power to detect different directions of effects, the ELRA shows sufficient sensitivity and salinity tolerance
to discriminate receptor-binding potentials in environmental samples.
Conclusions The optimised ELRA assay is a fast, cost-effective, reliable and highly reproducible tool that can be used for high-throughput
screening in a microplate format in detecting both estrogenic and anti-estrogenic effects. Additionally, the ELRA is robust
against microbial contaminations, and is not susceptible towards cytotoxic interferences like the common cell-culture methods.
The general applicability and sufficient sensitivity of the ELRA was shown in freshwater environments. Marine and brackish
samples can be measured up to salinity levels of 20.5‰.
Recommendations and perspectives In view of the proven sensitivity, functionality and the fastness of the ELRA, it is recommendable to standardise the test
method. At the moment, no adequate in vitro test procedure exists which is standardised to DIN or ISO levels. The E-screen
and the yeast estrogen/androgen screens (YES/YAS) sometimes underlie strong cytotoxic effects, as reported in the first part
of this study. Further development of an ELRA assay using human androgen receptors appears to be very promising to gain information
about androgenic and anti-androgenic effects, too. This would offer a possibility to use the ELRA as a fast and reliable pre-screening
tool for the detection of endocrine potentials, thus minimising time and cost-expensive animal experiments. 相似文献
10.
Sayuri Shimazu Masaya Ohta Hideyuki Inui Yoshihiko Nanasato Hitoshi Ashida Hideo Ohkawa 《Journal of environmental science and health. Part. B》2013,48(8):750-756
The transgenic Arabidopsis plants carrying a recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system were generated for assays of polychlorinated biphenyl (PCB) congeners. The selected transgenic Arabidopsis plant XgD2V11-6 exhibited a correlation between uptake of PCB126 and PCB126-induced GUS activity. Also, the plants showed induced GUS activity towards the supplemental indole 3-acetic acid (IAA). Thus, the GUS assay may reflect induction by both endogenous and exogenous AhR ligands. When biosurfactants, MEL-B, produced in the culture of yeast isolated from plants were used for assays of PCB congeners in the transgenic Arabidopsis plants, they showed marked PCB126 dose-dependent and toxic equivalency factor (TEF) dependent GUS activities. The effects of biosurfactants were clearer when the plants were cultivated on soils containing PCB congeners for 7 days as compared with on soils for 3 days as well as in the medium for 3 days. Threfore, it was estimated that biosurfactants form micellae with PCB congeners, which are easily uptaken by the plants in a mode of passive diffusion, transport into the aerial parts and then induce GUS activity. 相似文献