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91.
Zhao  Yu  Ma  Chen  Yang  Jie  Zou  Xiufen  Pan  Zishu 《中国病毒学》2021,36(6):1327-1340
Virologica Sinica - Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections in children. Inactivated RSV vaccine was developed in the late 1960’s, but the...  相似文献   
92.
Luo  Shengxue  Zhang  Panli  Zou  Peng  Wang  Cong  Liu  Bochao  Wu  Cuiling  Li  Tingting  Zhang  Ling  Zhang  Yuming  Li  Chengyao 《中国病毒学》2021,36(5):1113-1123
Virologica Sinica - SARS-CoV-2 has caused more than 3.8 million deaths worldwide, and several types of COVID-19 vaccines are urgently approved for use, including adenovirus vectored vaccines....  相似文献   
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Lung cancer is the most aggressive tumour afflicting patients on a global scale. Extracellular vesicle (EV)-delivered microRNAs (miRs) have been reported to play critical roles in cancer development. The current study aimed to investigate the role of hypoxic bone marrow mesenchymal cell (BMSC)-derived EVs containing miR-328-3p in lung cancer. miR-328-3p expression was determined in a set of lung cancer tissues by RT-qPCR. BMSCs were infected with lentivirus-mediated miR-328-3p knock-down and then cultured in normoxic or hypoxic conditions, followed by isolation of EVs. Following ectopic expression and depletion experiments in lung cancer cells, the biological functions of miR-328-3p were analysed using CCK-8 assay, flow cytometry and Transwell assay. Xenograft in nude mice was performed to test the in vivo effects of miR-328-3p delivered by hypoxic BMSC-derived EVs on tumour growth of lung cancer. Finally, the expression of circulating miR-328-3p was detected in the serum of lung cancer patients. miR-328-3p was highly expressed in EVs derived from hypoxic BMSCs. miR-328-3p was delivered to lung cancer cells by hypoxic BMSC-derived EVs, thereby promoting lung cancer cell proliferation, invasion, migration and epithelial-mesenchymal transition. miR-328-3p targeted NF2 to inactivate the Hippo pathway. Moreover, EV-delivered miR-328-3p increased tumour growth in vivo. Additionally, circulating miR-328-3p was bioactive in the serum of lung cancer patients. Taken together, our results demonstrated that hypoxic BMSC-derived EVs could deliver miR-328-3p to lung cancer cells and that miR-328-3p targets the NF2 gene, thereby inhibiting the Hippo pathway to ultimately promote the occurrence and progression of lung cancer.  相似文献   
95.
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers.  相似文献   
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The IGF system is one of the most important endocrine and paracrine growth factor systems that regulate fetal and placental growth, whereas the liver is the principal source of circulation IGF-I. In the present study, expression of IGF-I, IGF type-I receptor (IGF-IR), and IGF binding protein (IGFBP)-3 genes was quantified by RT-PCR in the liver tissue on days 13, 17, 21, 25, and 27 of embryonic development, as well as at 7 days post-hatching (PH) in meat-type Gaoyou ducks and egg-type Jinding ducks. The results showed that IGF-I mRNA could be detected as early as on E 13d, but the expression level was low throughout embryonic development before increasing dramatically by E 27d and 7 days PH in both duck breeds. However, Gaoyou ducks exhibited higher IGF-I mRNA level than Jinding ducks, and the differences were significant on E 13d, E 21d, and at 7 days PH. Expression of IGF-IR in liver increased gradually in the former stages of the embryonic development, reaching its highest point on E 21d, and then declined up until 7 days PH. The expression pattern of IGFBP-3 gene was similar to that of IGF-IR gene, increasing significantly from E 17d. The expression peak appeared on E 25d, then declined significantly just prior to hatching (day 27) and was followed by an increase at 7 days PH. In general, the expression level of IGF-IR and IGFBP-3 genes in Jinding ducks was higher than that in Gaoyou ducks. Inverse relationships were observed for the expression of IGF-I and IGF-IR, and IGF-I and IGFBP-3, whereas a positive relationship was observed for the expression of IGF-IR and IGFBP-3. Our data indicate a differential expression of selected genes that comprise the IGF system in the duck liver tissue during embryonic and early PH growth and development.  相似文献   
99.
Self‐interference is one of the most important selective forces in shaping floral evolution. Herkogamy and dichogamy both can achieve reductions in the extent of self‐interference, but they may have different roles in minimizing self‐interference in a single species. We used four self‐incompatible Epimedium species to explore the roles of herkogamy and dichogamy in avoiding self‐interference and to test the hypothesis that herkogamy and dichogamy may be separated and become selected preferentially in the taxa. Two species (Efranchetii and Emikinorii) expressed strong herkogamy and weak protogyny (adichogamy), whereas another two species (Esutchuenense and Eleptorrhizum) expressed slight herkogamy and partial protandry. Field investigations indicated that there was no physical self‐interference between male function and female function regarding pollen removal and pollen deposition in all species. Self‐pollination (autonomous or facilitated) was greater in species with slight herkogamy than in those with strong herkogamy. Artificial pollination treatments revealed that self‐pollination could reduce outcrossed female fertility in all species, and we found evidence that self‐interference reduced seed set in E. sutchuenense and E. leptorrhizum in the field, but not in E. franchetii and E. mikinorii. These results indicate that well‐developed herkogamy is more effective compared with dichogamy in avoiding self‐interference in the four species. In genus Epimedium, herkogamy instead of dichogamy should be selected preferentially and evolved as an effective mechanism for avoiding self‐interference and might not need to evolve linked with dichogamy.  相似文献   
100.
Altered expressions of receptor for advanced glycation end-products (RAGE) and its ligand (S100A9) are observed in many cancers and play a key role in inflammation-associated cancer. In our previous study, by two-dimensional gel electrophoresis followed by mass spectrometry, the expression of S100A9 protein was found to increase in squamous cervical cancer compared with adjacent normal cervical tissues. Therefore, in the present study we observed the expressions of S100A9 and RAGE in 30 chronic cervicitis, 50 cervical intraepithelial neoplasia (CIN), and 40 squamous cervical cancer (SCC) using immunohistochemical analysis and analyzed the differential expression and possible role of S100A9 and RAGE in cancer development. Immunohistochemical findings were as follows: the expressions of S100A9 and RAGE were demonstrated in chronic cervicitis, CIN, and SCC. Moreover, their expressions were gradually increasing as the tumor progressed. In SCC, the staining scores of S100A9 and RAGE were significantly higher in well-differentiated tumors compared to moderately and poorly differentiated tumors. The expression of S100A9 in epithelial cells exhibited a positive correlation to RAGE expression in chronic cervicitis, CIN, and SCC. There were no significant difference of S100A9 immunoreactivity in stromal cells among chronic cervicitis, CIN, and SCC. Moreover, there was no correlation between S100A9 immunoreactivity in stromal cells of SCC and clinicopathological parameters. Finally, double immunohistochemistry illustrated that RAGE and S100A9 co-express in SCC. In conclusion, RAGE binds its ligand (S100A9), which plays an important role in the development of SCC. In addition, the expressions of S100A9 and RAGE in SCC tumor cells were closely associated with histological differentiation.  相似文献   
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