Advance in clinical application of non-invasive prenatal screening using cell-free fetal DNA / 中华医学遗传学杂志

Non-invasive prenatal screening using cell-free fetal DNA (NIPS) has been integrated into the prenatal health care only in a short span of five years, and the guidelines provided by professional bodies have been continuously updated. The American College of Medical Genetics and Genomics has made a statement on NIPS in July, 2016, suggesting that the NIPS can replace conventional screening for Patau, Edwards and Down syndromes in a continuum of gestational age and for any maternal age, except those who are significantly obese. The scope of target diseases of NIPS are also growing. Meanwhile, pre- and post-test counseling for NIPS has put forward a greater challenge for medical professionals.

Experimental studies on acute toxicity of Achyranthes Aspera / 国际中医中药杂志

Objective To observe the acute toxicity of local achyranthes aspera, and its injury to major internal organs. Methods Estimated the dose before the experiment, then selected 40 mice and divided them into five groups randomly, namely 4 dose-groups and one control group. The doses used in the dose-groups were 400 g/kg, 300 g/kg, 225 g/kg and 169 g/kg respectively. Observed the symptoms and the death for successive 7 days and calculated LD (50)with statistic methods. Dissected the dead mice and observed the lesion of organs. Results The LD50 of acute toxicity test of achyranthes aspera was 309.21 g/kg, Sx=0.0359 g/kg. 95% of the limit of trust was 309.14～309.28 g/kg. According to the acute toxic standard, it belonged to non-toxicity. The specimen revealed that large dose administration caused coagulation of blood in both liver and spleen. Conclusion Local achyranthes aspera had little toxicity. Large dose administration affected heart function of mice.

Preparation and properties of calcium silicate-phosphate composite bone cements / 生物医学工程学杂志

In this paper, alpha-tricalcium phosphate (alpha-TCP) and tetracalcium phosphate (TTCP) respectively were chosen as basic compositions of phosphate bone cements. Other auxiliary materials such as hydroxyapatite (HAP), dicalcium phosphate dihydrate (DCPD), calcium carbonate (CaCO3), calcium oxide (CaO) and amorphous calcium silicate (CaSiO3) were added in the cements. Six kinds of composite bone cements were decided with 1.50 as their Ca/P ratio. Then the primary properties of them were studied. Ringer's simulated body fluid (SBF) tests were carried out for the samples. The changes of pH value in SBF and the compressive strength of the samples with the immersion time were studied. The results showed: the mixing liquid 0.25 M K2HPO4/KH2PO4 and amorphous CaSiO3 were effective for accelerating the setting of the cements; the initial setting time (It) was about 4-5.5 min and the final setting time (Ft) was about 18-19. 5 min. Amorphous calcium silicate can increase the compressive strength of the bone cements remarkably; the compressive strength of the alpha-TCP bone cement with the addition of suitable amount amorphous CaSiO3 reached 45.3 MPa after immersion in SBF for 14 days.