No abstract

This study is to determine accuracy of abdominal ultrasound and nuclear magnetic resonance imaging (MRI) for placenta accreta in the second and third trimester of pregnancy and to define the most relevant features of abdominal ultrasound and MRI for placenta accreta prediction. Between September 2012 and September 2018, 245 high risk of placenta accreta in the second trimester of pregnancy were prenatal diagnosed by abdominal ultrasound and MRI and they were followed up until the end of pregnancy. Forty-six patients at the second trimester of pregnancy and 40 patients at the third trimester of pregnancy were confirmed as placenta accreta. For the second and third trimester of pregnancy, the sensitivity (Se), specificity (Sp), positive and negative predictive value (PPV and NPV) of abdominal ultrasound were 95.65% versus 97.50%, 91.78% versus 90.70%, 88% versus 83%, and 97% versus 99%, respectively, while the Se, Sp, PPV, and NPV of MRI were 89.13% versus 92.50%, 87.67% versus 8721%, 82% versus 77%, and 93% versus 96%, respectively. Five features having significant statistical differences between normal placentation women and placenta accreta patients in second or third trimester of pregnancy, including loss of the normal retroplacental clear space, thinning or disappearance of the myometrium, increased vascularization at the uterine serosa-bladder wall interface, and vascularization perpendicular to the uterine wall on abdominal ultrasound, and uterine bulging and dark intraplacental bands on MRI. Abdominal ultrasound and MRI for placenta accreta in the second and third trimester of pregnancy could provide meaningful imaging evidences.

Effectiveness of cancer therapy relies heavily on the efficient early diagnosis. Circulating tumor DNA (ctDNA) detection is one of the most clinically meaningful liquid biopsy approaches for the noninvasive cancer early diagnosis, which, unfortunately, cannot be applied as a routine diagnostic tool till a number of obstacles, for example, unsatisfactory specificity and sensitivity, and extremely high costs, are overcome. Here, the first paradigm of nanomaterial's application in the extremely specific, ultrasensitive, and yet economical ctDNA detections is reported based on a facile nanoparticle-coupling strategy without amplification, with which polymerase chain reaction (PCR)-introduced bias and other shortcomings are successfully circumvented. Aiming at seven Kirsten rat sarcoma-2 virus (KRAS) point mutations, the present strategy exhibits high specificity and an ultrahigh sensitivity of detecting as low as 0.1 pg mL of KRAS point mutation without prior PCR amplification. Discriminating KRAS gene mutations in lung adenocarcinoma patients at an extremely low detection limit equivalent to 0.12% mutation relative to wild-type gene is successful. It is envisioned that this nanoparticle-coupling approach could be routinely applied clinically for ultra-early diagnosis and monitoring of diverse malignant tumors, thus facilitating the fight against cancer.