Study of mechanism of medicine actions, by quantitative analysis of cultured cardiac myocyte, is one of the cutting edge researches in myocyte dynamics and molecular biology. The characteristics of cardiac myocyte auto-beating without external stimulation make the research sense. Research of the morphology and cardiac myocyte motion using image analysis can reveal the fundamental mechanism of medical actions, increase the accuracy of medicine filtering, and design the optimal formula of medicine for best medical treatments. A system of hardware and software has been built with complete sets of functions including living cardiac myocyte image acquisition, image processing, motion image analysis, and image recognition. In this paper, theories and approaches are introduced for analysis of living cardiac myocyte motion images and implementing quantitative analysis of cardiac myocyte features. A motion estimation algorithm is used for motion vector detection of particular points and amplitude and frequency detection of a cardiac myocyte. Beatings of cardiac myocytes are sometimes very small. In such case, it is difficult to detect the motion vectors from the particular points in a time sequence of images. For this reason, an image correlation theory is employed to detect the beating frequencies. Active contour algorithm in terms of energy function is proposed to approximate the boundary and detect the changes of edge of myocyte.
Algorithms ; Animals ; Animals, Newborn ; Cell Movement ; Cells, Cultured ; Female ; Image Interpretation, Computer-Assisted ; Image Processing, Computer-Assisted ; Myocardial Contraction ; Myocytes, Cardiac ; cytology ; Pregnancy ; Rats ; Rats, Wistar

OBJECTIVE: To study the influence of maternal sex chromosomal abnormalities on the prediction of fetal sex chromosome abnormalities (SCAs) by non-invasive prenatal testing (NIPT). METHODS: Thirty-six pregnant women with a prediction for fetal SCAs by NIPT were verified as false positive after prenatal diagnosis using amniotic fluid samples. With informed consent, these women were subjected to chromosomal karyotyping or copy number variations (CNVs) analysis through high-throughput sequencing. RESULTS: Sex chromosomal abnormalities were found in 8 women, which yielded an abnormal rate of 22.22% (8/36). Among these, 3 had sex chromosome aneuploidies (47, XXX), 4 had sex chromosome mosaicisms, and 1 carried structural chromosomal abnormalities. Reanalysis of the results of NIPT were consistent with the maternal CNVs by large. With the ratio of cffDNA (ChrX)/cffDNA was more than 2, 6 of the eight women were found to harbor sex chromosome abnormalities, and the fetal karyotype was normal. However, with a ratio of less than 2, only 2 of the 38 pregnant women had sex chromosome abnormalities, and 10 of the fetuses were confirmed as positive. CONCLUSION The presence of maternal sex chromosomal abnormalities can greatly influence the result of NIPT, which may also be an important reason for false prediction for fetal SCAs by NIPT. When NIPT indicates abnormal SCAs, it is necessary to analyze maternal sex chromosomes. The ratio of cffDNA(ChrX)/cffDNA may help to determine the source of abnormal signals.