Expression of TET and 5-HmC in Trophoblast Villi of Women with Normal Pregnancy and with Early Pregnancy Loss

Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy. The ten-eleven translocation （TET） family and 5-hydroxymethylcytosine （5-hmC） were found to be linked with epigenetic reprogramming. The present study aimed to examine the expression of the TET family and 5-hmC in the villi of human embryos and compared their expression between normal pregnancy and early pregnancy loss （EPL）. Embryonic villi were collected from normal pregnant women （control） experiencing medical abortion and from EPL patients at gestation ages of 6, 7 and 8 weeks. The mRNAs of TET family were analysed using quantitative polymerase chain reaction （qPCR）, and TET proteins using Western blotting and immunohistochemical analysis. The MethylFlashTM Kit was used to quantify the absolute amount of 5-methylcytosine （5-mC） and 5-hmC. Our results showed that the expression of the TETs and 5-hmC in the normal villus decreased with increasing gestational age. Immunohistochemistry revealed that the TET proteins were expressed in the cytoplasm of trophoblasts and their expression was the highest in the 6-week tissue samples, which was consistent with the qPCR and Western blot results. The expression of TET1, TET2, and TET3 was lower in the villi in EPL group than in normal pregnancy group （P〈0.05 for all）. It was concluded that the TET family and 5-hmC are critical in epigenetic reprogramming of human embryo. The findings also suggest that a deficiency of TETs in the villus might be associated with human EPL.

Corrosion resistance properties of colored zirconium conversion coating and powder coating on cold-rolled steel

Jiuhe Corporation developed a new surface pretreatment for producing a phosphate-free and colored zirconium conversion coating on cold-rolled steel(CRS).Scanning electron microscopy(SEM)and energy-dispersive spectroscopy(EDS)were applied to study the surface morphology and elemental composition of the golden yellow-colored conversion coating.Elec trochemic al impedance spectroscopy(EIS)was used to investigate the electrochemical performance of the conversion coatings with different colors.The corrosion resistance properties of the powder coatings were characterized using the neutral salt spray test(NSS)and the tape adhesion test.The EIS and NSS results demonstrate that the colored zirconium conversion coatings exhibit excellent corrosion resistance properties compared with the bare CRS.The golden yellow-colored conversion coating has a maximum EIS value(748Ω·cm^(2))and achieves 0 mm degree of corrosion,as stipulated by EN ISO 4628-8.This paper proposes a hypothesis concerning the ZrO_(2)-(β-FeOOH)-polymer conversion reaction to explain the color changes.

Selective Short-term Fertilization Combined with Early Rescue ICSI: An Optimal Strategy for Patients at High Risk for Fertilization Failure

Objective To investigate clinical outcomes in patients who were at more precise criteria risks for fertilization failure and were treated with selective, short-term fertilization （oocytes and sperm co-incubated for 4 h） and early rescue intracytoplasmic sperm injection （ICSI）. Methods A retrospective analysis was performed on 2023 women undergoing assisted reproductive technology （ART）. They were assigned to 4 groups： short-term in vitro fertilization （short-term IVF,, group A, n=217）, regular IVF （oocytes and sperm coincubated overnight, group B, n=1475）, short-term IVF and early rescue ICSI （shortterm ICSI, group C, n=94）, and regular ICSI （group D, n=237）. Results In group A, 69.8% （217/311） achieved normal fertilization rates, and the complete fertilization failure rate （fertilization rate was 0%） was 12.9% （40/311）. But all of the fertilization failure oocytes got rescue ICSI. In group B, the complete fertilization failure rate was 1.1% （19/1 692）. The fertilization rate, 2 PN （pronucleus） rate, and i PN rate were significantly lower in group A than those in group B （70.9% vs 80.8%, 57.8% vs 66.3%, and 3.5% vs 6.2%, respectively）. No significant differences were observed in clinical pregnancy rates and birth defect rates between groups A and B. The fertilization rates in groups C and D did not significantly differ （77.9% vs 76.2%）, which was also true for birth defect rates. The clinical pregnancy rate of group C was higher than that of group D （51.2% vs 42.3%）, but this difference was not significant （P〉0. 05）.Conclusion These results suggested that selective, short-term fertilization can result in effective outcomes for patients who were at high risk for fertilization failure.