Effects of 60Co γ-rays on brain injury and polarization of microglia/macrophages in mice / 中华微生物学和免疫学杂志

Objective:To analyze the damage in hippocampal tissues of mice after whole-body irradiation with high- or low-dose ionizing radiation and to investigate the roles of microglia/macrophages polarization in the injury.Methods:C57BL/6 mice were randomly divided into three groups: sham irradiation group, low-dose group (0.05 Gy) and high-dose group (7 Gy). Low- and high-dose groups were respectively treated by whole-body irradiation with single dose of 60Co γ-rays. Hippocampal tissues of the mice were collected at 6 h, 1 d, 3 d and 7 d after irradiation. The morphology, structure and apoptosis of neurons were detected by HE staining, Nissl staining and Tunnel staining, respectively. RT-PCR and immunofluorescence assay were performed to detect the expression of M1 and M2 microglial markers at mRNA and protein levels in hippocampus tissues. The cognitive and emotional behaviors of mice were evaluated one month after the irradiation by Morris water maze, open field test, elevated plus maze and tail suspension test. Results:There were morphological and structural changes in the nerve cells in the hippocampus region of mice after irradiation, accompanied by apoptosis. Acute injuries occurred at 6 h after radiation, alleviated at 1 d and 3 d, and persisted at 7 d in a dose-dependent manner. The results of immunofluorescence staining and confocal imaging analysis showed that compared with the sham irradiation group, the high-dose group showed increased number of microglia, down-regulated expression of M1 microglial markers and up-regulated expression of M2 microglial markers in the hippocampus at 6 h and 1 d after radiation, while M2 microglial markers decreased at 3 d and 7 d after irradiation. PCR results showed that the expression of M1 and M2 microglial markers at mRNA level in the irradiation groups increased at 6 h after irradiation, but there was no statistical significance. The expression of related proinflammatory/anti-inflammatory factors was significantly up-regulated. The results of behavioral experiments showed that compared with the sham irradiation group, there was no statistical difference in cognitive or emotional behaviors at one month after irradiation.Conclusions:60Co γ-rays could damage mouse hippocampal tissues and result in the overexpression and different polarization patterns of microglia/macrophages in mice.

Plant prime editing technique: a new genome editing tool for plants / 生物工程学报

The CRISPR/Cas9 based prime editing (PE) technique enables all 12 types of base substitutions and precise small DNA deletions or insertions without generating DNA double-strand breaks. Prime editing has been successfully applied in plants and plays important roles in plant precision breeding. Although plant prime editing (PPE) can substantially expand the scope and capabilities of precise genome editing in plants, its editing efficiency still needs to be further improved. Here, we review the development of PPE technique, and introduce structural composition, advantages and limitations of PPE. Strategies to improve the PPE editing efficiency, including the Tm-directed PBS length design, the RT template length, the dual-pegRNA strategy, the PlantPegDesigner website, and the strategies for optimizing the target proteins of PPE, were highlighted. Finally, the prospects of future development and application of PPE were discussed.

Recent advances in molecular targeted therapy and expression of iodine uptake relative protein in papillary thyroid carcinoma with BRAFV600E mutation / 中华内分泌代谢杂志

Type-B RAF (BRAF) gene is one of the most popular genes of thyroid carcinoma in recent studies,and its mutation has significant relationships with the occurrence,development,treatment,and prognosis of papillary thyroid carcinoma(PTC).The influence of BRAFV600E mutation on the expression of iodine uptake relative proteins in PTC cells and the value of molecular targeted therapy with BRAFV600Einhibitors in the clinical treatment of PTC in the future were summarized in this review.