Detection of trisomy 21 by quantitative fluorescent–polymerase chain reaction in uncultured amniocytes

Prenatal diagnosis of fetal trisomy 21 is usually performed by cytogenetic analysis. This requires lengthy laboratory procedures, high costs and is unsuitable for large-scale screening of pregnant women. Today, trisomy 21 can be rapidly diagnosed within 24 h by molecular analysis of uncultured fetal cells using the semi-quantification of fluorescent PCR products from short tandem repeat (STR) polymorphic markers. The aim of our study was to test a chromosome quantification method on the basis of the analysis of fluorescent PCR products derived from non-polymorphic target genes. Co-amplification of a portion of DSCR1 (Down syndrome Critical Region 1) and the reference gene, CFTR (cystic fibrosis transmembrane regulator) enabled molecular detection of trisomy 21. Our method was successfully tested on a total of 154 amniotic fluids in a blind prospective study. Calculation of the DSCR1/CFTR ratio allowed us to distinguish between 152 normal amniotic fluids (mean ratio 0.99) and 2 amniotic fluids presenting a trisomy 21 status (DSCR1/CFTR ratio of 1.53 and 1.61, respectively). The results obtained by conventional cytogenetic analysis and our quantitative PCR method were concordant in every case. Our gene-based fluorescent PCR approach represents an alternative molecular method for rapid and reliable detection of trisomy 21, which can be helpful in the prenatal diagnosis of women at high risk of fetal trisomy 21. Copyright © 2003 John Wiley & Sons, Ltd.     

Mapping green technologies literature published between 1995 and 2019: a scientometric review from the perspective of the manufacturing industry

Environmental Science and Pollution Research - This study presents a comprehensive literature review and gives an insight into the increasing research trends that are based on the discipline of...     

Biochemical responses,growth and reproduction of earthworm in low density polyethylene (LDPE)

There is an unprecedented production of plastic that is accelerating its disposal while affecting the fitness of the terrestrial as well as the aquatic environment. The term microplastics refers to plastic fragments that are less than 5 mm in size and are widely distributed in the environment. Therefore, the present study intends to explore the biological response of earthworms (Eisenia fetida) toward different concentrations of low-density polyethylene. E. fetida treated with low-density polyethylene concentration (Control), 250 mg kg⁻¹, 1000 mg kg⁻¹, 6000 mg kg⁻¹, 12,000 mg kg^−1, and 25,000 mg kg⁻¹. The above ratios were thoroughly mixed with 1kg of artificial soil and tested for growth, reproduction (cocoons and hatchling count), and enzymatic activities namely superoxide dismutase, guaiacol peroxidase, glutathione-S-transferase, and glutathione reductase and molecular docking studies. No mortality was observed during the exposure period at any concentrations. On the 28th day, when compared to the control the highest decrease in body weight of earthworms was observed in 25,000 mg (28.4%) followed by 12,000 mg (12.2%) and 6000 mg (3.4%). The cocoon and hatchlings significantly declined as the dose of microplastics increases. Enzymatic activity such as SOD and POD showed declined trend as the dose increased, while GST and GR increased with an increase in microplastic concentrations on 28th day. Furthermore, molecular docking showed that LDPE can modulate the activity of all four enzymes significantly.