[Study on the clinical significance of miR-100 expression in the invasion and metastasis of hepatocellular carcinoma].

Objective: To study the miR-100 expression levels in the tissues of hepatocellular carcinoma patients, and to further explore the correlation between miR-100 and the invasion and metastasis of hepatocellular carcinoma cells and its effect on patients' prognostic survival. Methods: Clinicopathological data of 70 cases that underwent hepatectomy from December 2013 to December 2016 in the Department of Hepatobiliary and Pancreatic Surgery of Henan Provincial People's Hospital were retrospectively analyzed. Real-time fluorescent quantitative PCR was used to detect the different miR-100 expression levels in cancerous and adjacent tissues. The expression of miR-100 with different clinicopathological features was compared, and the prognostic factors of patients with hepatocellular carcinoma were comprehensively analyzed. The correlation between miR-100 and patients' clinicopathological features was tested by χ(2). Kaplan-Meier method was used to draw the survival curve. Log-rank test was used to examine the survival rate difference in each subgroup. Cox regression model was used to analyze the multivariate prognosis. Results: miR-100 expression was down-regulated to a different degree in hepatocellular carcinoma tissues than the corresponding adjacent tissues. Among them, the down-regulated expression of miR-100 in hepatocellular carcinoma tissues accounted for 82.9% (58/70, P < 0.05) of all cases when compared to corresponding paracancerous tissues. miR-100 expression level was significantly correlated to high Edmondson's grade, high TNM stage and intrahepatic metastasis (P < 0.05). The overall survival time of miR-100 positive expression was significantly higher than that of miR-100 negative expression (Log-rank χ(2) = 8.257, P < 0.05). Univariate survival analysis results revealed that the miR-100 expression level, tumor size, TNM stage, Edmondson's grade, and presence or absence of venous tumor thrombosis had a poor prognosis (P < 0.05). Cox multivariate regression analysis showed that the tumor size, Edmondson's grade, and miR-100 expression level were independent factors affecting the prognostic survival in hepatocellular carcinoma patients. In addition, patients with low positive expression rate of miR-100, large tumors and high Edmondson's grade had a poor prognosis. Conclusion: The level of miR-100 expression in hepatocellular carcinoma cells is low, so it is closely related to the invasion and metastasis and affects the prognostic survival of hepatocellular carcinoma patients.

Phase transformation of Cu-rich precipitates from 9R to 3R variant via ledges mechanism in ferritic steel containing copper.

Precipitates and solute enrich in aged ferritic steel containing copper were examined using high-resolution electron microscopy, high-angle annular dark-field scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy. Two ledges with one-atom and two-atom layers height in the 9R/3R interface were observed. The enrichment of copper into two successive closed-packed planes with an interval of Fe-rich close-packed plane was detected. The passage of the Shockley partial, or the shearing, changes the stacking sequence of closed-packed planes. Finally, 9R Cu variant transformed into 3R Cu variant.

Establishment and rapid detection of a heterozygous missense mutation in the CACNA1F gene by ARMS technique with double-base mismatched primers.

Retinitis pigmentosa (RP) is a retinal degenerative disorder that often causes complete blindness. Mutations of more than 50 genes have been identified as associated with RP, including the CACNA1F gene. In a recent study, by employing next-generation sequencing, we identified a novel mutation in the CACNA1F gene. In this study, we used the amplification refractory mutation system (ARMS) and identified a single nucleotide change c.1555C>T in exon 13 of the CACNA1F gene, leading to the substitution of arginine by tryptophan (p.R519W) in a Chinese individual affected by RP. This study actually confirms this novel mutation, and establishes the ARMS technique for the detection of mutations in RP.

Isolation and analysis of cell-free fetal DNA from maternal peripheral blood in Chinese women.

Non-invasive prenatal diagnosis is used to detect the genetic material of the fetus by isolating the cell-free fetal DNA (cffDNA) from maternal peripheral blood. In order to establish an isolation method for cffDNA from maternal peripheral blood in Chinese women, the cffDNA was acquired with a two-step centrifugation using a QlAamp DNA Blood mini kit. The SRY gene of plasma DNA was amplified by polymerase chain reaction (PCR). Real-time quantitative PCR was used to measure the concentration of cffDNA in maternal peripheral blood in different pregnant women. The results of the SRY gene amplification of plasma DNA from pregnant women was the same as that of the amniocyte DNA. The average concentration of cffDNA in maternal peripheral blood of pregnant women in different gestational stages was 0.98 ng/mL (0.26-1.49 ng/mL), 1.43 ng/mL (0.46- 2.34 ng/mL), and 1.95 ng/mL (0.65-6.81 ng/mL) from early, middle, and late gestational stages, respectively. The mean of cffDNA from total DNA in plasma in different stages of gestation was 22.28% (9.86-27.81%). The lowest concentration of DNA amplified by nested-PCR in our research was 10-4-10-3 ng/µL. The isolation method for cffDNA from maternal peripheral blood was successfully established and further research into its applications will be conducted.