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991.
Yuru Fan Wenwen Hou Yuan Xing Li Zhang Chunxiu Zhou Jing Gui Pengfei Xu Anming Wang Xuemei Fan Xin Zeng Shanwu Feng Ping Li 《Journal of cellular biochemistry》2020,121(2):1890-1900
Preterm birth (PTB) is a major cause of neonatal mortality, with a poorly understood etiology. The regular contraction of the myometrium was considered as contributing to the etiology of the onset of labor, especially PTB. Thus, studying the mechanism of myometrium contraction is very important for understanding the initiation of labor and also for preventing PTB. Using liquid chromatography-mass spectrometry, we found 322 significantly differential peptides in myometrium tissues between term nonlabor and term labor groups (absolute fold change ≥ 2 and P < .05). We next analyzed length, molecular weights, isoelectric point, and cleavage site of all the different peptides. We, next, analyzed the functions of different peptides through their precursor proteins by Gene Ontology, enrichment and canonical pathway analysis. The results indicated that the extracellular matrix (ECM) played a major role in biological process, the cellular component, and molecular function categories, and revealed that ECM remodeling played a vital role in myometrial contraction. In addition, some known signaling, such as corticotropin-releasing hormone signaling and calcium signaling were proven to be involved in this process. Ingenuity Pathways Analysis upstream regulator analysis suggested that some of the known molecules, which reportedly were very important in labor onset, were included, for example, nuclear factor κB, tubulin, and phosphoinositide 3-kinase. We also identified 23 peptides derived from the precursor protein TITIN, of which 21 peptides sequences from TITIN were located in functional domains. These results suggested that peptides play an important role in labor onset and provide further insight into PTB therapy. 相似文献
992.
Jin Zhang Meng Xie Mi Li Jinhua Ding Yunqiao Pu Anthony C. Bryan William Rottmann Kimberly A. Winkeler Cassandra M. Collins Vasanth Singan Erika A. Lindquist Sara S. Jawdy Lee E. Gunter Nancy L. Engle Xiaohan Yang Kerrie Barry Timothy J. Tschaplinski Jeremy Schmutz Gerald A. Tuskan Wellington Muchero Jin‐Gui Chen 《Plant biotechnology journal》2020,18(3):859-871
993.
Qiuyun Wu Lei Han Wenwen Gui Feng Wang Weiwen Yan Hua Jiang 《Journal of cellular and molecular medicine》2020,24(24):14339
Inhalation and deposition of crystalline silica particles in the lung can cause pulmonary fibrosis, then leading to silicosis. Given the paucity of effective drugs for silicosis, new insights for understanding the mechanisms of silicosis, including lung fibroblast activation and myofibroblast differentiation, are essential to explore therapeutic strategies. Our previous research showed that the up‐regulation of miR‐503 alleviated silica‐induced pulmonary fibrosis in mice. In this study, we investigated whether miR‐503 can regulate the TGF‐β1‐induced effects in lung fibroblasts. Mimic‐based strategies aiming at up‐regulating miR‐503 were used to discuss the function of miR‐503 in vivo and in vitro. We found that the expression level of miR‐503 was decreased in fibroblasts stimulated by TGF‐β1, and the up‐regulation of miR‐503 reduced the release of fibrotic factors and inhibited the migration and invasion abilities of fibroblasts. Combined with the up‐regulation of miR‐503 in a mouse model of silica‐induced pulmonary fibrosis, we revealed that miR‐503 mitigated the TGF‐β1‐induced effects in fibroblasts by regulating VEGFA and FGFR1 and then affecting the MAPK/ERK signalling pathway. In conclusion, miR‐503 exerted protective roles in silica‐induced pulmonary fibrosis and may represent a novel and potent candidate for therapeutic strategies in silicosis. 相似文献
994.
Yong‐Gang Hu Yi‐Hong Shen Ze Zhang Gui‐Qin Shi 《Archives of insect biochemistry and physiology》2013,83(1):41-55
The phenomenon that epidermal cells under the white stripes rather than black stripes contain many uric acid granules was found in larvae of several Lepidopteran species. However, the biological mechanism of this phenomenon is still unknown. In the present study, we take advantage of several silkworm (Bombyx mori) body color mutant strains to investigate the deposition patterns and biological mechanism of urate and melanin in the integuments of these mutant larvae. By imaging with transmission electron microscope, we found that there were some melanin granules in the larval cuticle in black body color mutant plain Black (pB), but not in background strain plain (p) with white larval body color. In contrast, the larval epidermal cell of background strain had much more urate granules than that of black one. Furthermore, the uric acid content under the black stripes was significantly lower than that under the white stripes in a single individual of mottled stripe (pS) with black and white stripes in each segment. Ultraviolet A (UVA) exposure experiments showed that the distinct oily (od) mutant individuals with translucent larval integument were more sensitive to the UVA damage than black body color mutant and background strain without any pigmentation in the larval cuticle. This is likely due to the absence of melanin granules and few urate granules in the integument of od mutant. Thus, both the deposited melanin granules in the cuticle and the abundant urate granules in the epidermis cells constitute effective barriers for the silkworm to resist UVA‐induced damage. 相似文献
995.
Peng C Liu HY Zhou M Zhang LM Li XL Shen SR Li GY 《Molecular and cellular biochemistry》2007,303(1-2):141-149
BRD7 is a novel gene which involved NPC in our lab. Our previous studies showed that BRD7 was expressed at high level in normal
nasopharyngeal epithelial tissues, but at low level in nasopharyngeal carcinoma biopsies and cell lines. In these papers,
we found that ectopic expression of BRD7 can decrease cell proliferation and capability to form colonies in soft agar. FCM
(Flow cytometry) assay indicated that the cell cycle progression from G1 to S phase was inhibited and the expression of cyclinD1
was significantly decreased after being transfected with BRD7 in HNE1 cells (NPC cells). To further investigate the molecular
mechanism of BRD7 suppression of NPC cells growth, the cDNA microarray was performed to detect difference in gene expression
profile induced by BRD7. The results indicated that 21 genes expression were changed after being transfected with BRD7 and
the differentially expressed gene including α-catenin, cyclinD1, E2F3 was confirmed by western-blot. Next, we found that even
though no obvious changes of the total expression of β-catenin were observed, the accumulation of β-catenin in nucleus was
blocked. In addition, it was found that the expression of β-catenin was up-regulated in the complex composed of β-catenin
and α-catenin in HNE1 cells induction of BRD7. So, we concluded that over-expression of BRD7 increased the expression of α-catenin
which “hold” β-catenin in the complex and inhibited its accumulating in nucleus. At last, we demonstrated the c-jun, p-MEK,
and p-ERK1/2 expression were down-regulated, and the Ap-1 promoter activity was inactive after being transfected with BRD7.
We also found that over-expression of BRD7 can inactivate the c-jun and p-ERK1/2 after being treated with EGF in HNE1 cells.
These results indicated that BRD7 played a negative role in ERK1/2 pathway. Taken together, our present results provide new
insights for BRD7 function to inhibit NPC cells growth through negative regulating β-catenin and ERK1/2 pathways. 相似文献
996.
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999.
Xingqi Wang Yong Zhang Shuangying Gui Jie Huang Jiaojiao Cao Zhengguang Li Qian Li Xiaoqin Chu 《AAPS PharmSciTech》2018,19(5):2023-2040
Liquid crystals (LCs) are conventionally divided into thermotropic or lyotropic, based on the organization and sequence of the controlled molecular system. Lipid-based lyotropic liquid crystal (LLC), such as lamellar (Lα), bicontinuous cubic (QII), or hexagonal (HII) phases, have attracted wide interest in the last few decades due to their practical potential in diverse applications and notable structural complexity. Various guest molecules, such as biopharmaceuticals, chemicals, and additives, can be solubilized in either aqueous or oily phase. And the LLC microstructure can be altered to affect the rate of drug release eventually. To utilize these microstructural variations to adjust the drug release in drug delivery system (DDS), it is crucial to understand the structure variations of the LLC caused by different types of guest molecules. Therefore, in this article, we review the effect of guest molecules on lipid-based LLC microstructures. In particular, we focus on the different characterization methods to evaluate this change caused by guest substances, such as polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), self-diffusion nuclear magnetic resonance (SD-NMR), and so on. 相似文献
1000.