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31.
A confluent PtK2 cell sheet was incised in a serum-free culture medium, at 15 min, 2 hr and 24 hr after wounding. The culture media were collected in the same way and used as conditioned media. Unwounded confluent cells were cultured in the conditioned medium for 24 hr. They showed a modification of fibronectin localization similar to that which we had previously observed in wounded confluent PtK2 cells: cells lost their normal fibronectin fibrils and were surrounded by fibronectin lace. This finding suggested that during wound healing, the cells released soluble chemical factors which could modify the fibronectin localization pattern of unwounded confluent cells. Subconfluent cells did not respond to conditioned media, showing that confluent cells and subconfluent cells had different susceptibilities. 相似文献
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33.
S. Han M. H. U. Khan Y. Yang K. Zhu H. Li M. Zhu O. Amoo S. U. Khan C. Fan Y. Zhou 《Plant biology (Stuttgart, Germany)》2020,22(4):709-721
- The CLE (CLAVATA3/ESR) gene family, encoding a group of small secretory peptides, plays important roles in cell‐to‐cell communication, thereby controlling a broad spectrum of development processes. The CLE family has been systematically characterized in some plants, but not in Brassica napus.
- In the present study, 116 BnCLE genes were identified in the B. napus genome, including seven unannotated, six incorrectly predicted and five multi‐CLE domain‐encoding genes. These BnCLE members were separated into seven distinct groups based on phylogenetic analysis, which might facilitate the functional characterization of the peptides.
- Further characterization of CLE pre‐propeptides revealed 31 unique CLE peptides from 45 BnCLE genes, which may give rise to distinct roles of BnCLE and expansion of the gene family. The biological activity of these unique CLE dodecamer peptides was tested further through in vitro peptide assays. Variations in several important residues were identified as key contributors to the functional differentiation of BnCLE and expansion of the gene family in B. napus. Expression profile analysis helped to characterize possible functional redundancy and sub‐functionalization among the BnCLE members.
- This study presents a comprehensive overview of the CLE gene family in B. napus and provides a foundation for future evolutionary and functional studies.
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35.
Mengmeng Zhuang Yuequ Deng Wenwen Zhang Bo Zhu Hao Yan Jiaqi Lou Pan Zhang Qingwei Cui Hao Tang Han Sun Yong Sun 《Cell death & disease》2021,12(6)
Intestinal mucosal injuries are directly or indirectly related to many common acute and chronic diseases. Long non-coding RNAs (lncRNAs) are expressed in many diseases, including intestinal mucosal injury. However, the relationship between lncRNAs and intestinal mucosal injury has not been determined. Here, we investigated the functions and mechanisms of action of lncRNA Bmp1 on damaged intestinal mucosa. We found that Bmp1 was increased in damaged intestinal mucosal tissue and Bmp1 overexpression was able to alleviate intestinal mucosal injury. Bmp1 overexpression was found to influence cell proliferation, colony formation, and migration in IEC-6 or HIEC-6 cells. Moreover, miR-128-3p was downregulated after Bmp1 overexpression, and upregulation of miR-128-3p reversed the effects of Bmp1 overexpression in IEC-6 cells. Phf6 was observed to be a target of miR-128-3p. Furthermore, PHF6 overexpression affected IEC-6 cells by activating PI3K/AKT signaling which was mediated by the miR-128-3p/PHF6 axis. In conclusion, Bmp1 was found to promote the expression of PHF6 through the sponge miR-128-3p, activating the PI3K/AKT signaling pathway to promote cell migration and proliferation.Subject terms: Cell growth, Cell migration 相似文献
36.
Deng-Guang Yu Christopher Branford-White Kenneth White Xue-Lian Li Li-Min Zhu 《AAPS PharmSciTech》2010,11(2):809-817
The objective of the present investigation was to prepare novel solid dispersions (SDs) of poorly water-soluble drugs with
special microstructural characteristics using electrospinning process. With the hydrophilic polymer polyvinylpyrrolidone as
the filament-forming polymer and acetaminophen (APAP) as the poorly water-soluble drug model, SDs having a continuous web
structure, and in the form of non-woven nanofiber membranes, were successfully prepared. The electrospun nanofiber-based SDs
were compared with those prepared from three traditional SD processes such as freeze-drying, vacuum drying, and heating drying.
The surface morphologies, the drug physical status, and the drug-polymer interactions were investigated by scanning electron
microscopy, differential scanning calorimetry, X-ray diffraction, and attenuated total reflectance Fourier transform infrared.
In vitro dissolution tests demonstrated that the electrospun nanofibers released 93.8% of the APAP content in the first 2 minutes
and that the dissolution rates of APAP from the different SDs had the following order: electrospun membrane > vacuum-dried
membrane ≈ freeze-dried membrane > heat-dried membrane. Electrospun nanofiber-based SDs showed markedly better dissolution-improving
effects than the other SDs, mainly due to their huge surface area, high porosity resulting from web structure, and the more
homogeneous distribution of APAP in the nanofiber matrix. 相似文献
37.
Earlier studies have suggested that indoleamine 2,3-dioxygenase (IDO) has a wide tissue distribution in mammals. However, detailed information on its cellular localization and also the levels of expression in various tissues is still scarce. In the present study, we sought to determine the cellular localization of IDO and also to quantify the level of its expression in various mouse tissues by using the branched DNA signal amplification assay, Western blotting, and immunohistochemical staining. The highest levels of constitutive IDO expression were found to be selectively present in the caput of epididymis, except for its initial segment. IDO expression was also detected inside the luminal compartment and even in the stereocilia within this region. In the prostate, high levels of IDO were selectively expressed in the capsular cells. In addition, high levels of IDO expression were also selectively detected in certain types of cells in the placenta, spleen, thymus, lung, and digestive tract. Notably, the morphological features of most of the positively stained cells in these organs closely resembled those of antigen-presenting cells. Based on the tissue distribution and cellular localization characteristics of IDO, it is hypothesized that its expression may serve two main functions: one is to deplete tryptophan in an enclosed microenvironment (such as in the epididymal duct lumen) to prevent bacterial or viral infection, and the other is to produce bioactive tryptophan catabolites that would serve to suppress T-cell–mediated immune responses against self-antigens, fetal antigens, or allogeneic antigens, in different situations. (J Histochem Cytochem 58:17–28, 2010) 相似文献
38.
39.
Yiwen Sun Zexuan Zhu Siping Chen Jega Balakrishnan Derek Abbott Anil T. Ahuja Emma Pickwell-MacPherson 《PloS one》2012,7(11)
The GP2 peptide is derived from the Human Epidermal growth factor Receptor 2 (HER2/nue), a marker protein for breast cancer present in saliva. In this paper we study the temperature dependent behavior of hydrated GP2 at terahertz frequencies and find that the peptide undergoes a dynamic transition between 200 and 220 K. By fitting suitable molecular models to the frequency response we determine the molecular processes involved above and below the transition temperature (T
D). In particular, we show that below T
D the dynamic transition is dominated by a simple harmonic vibration with a slow and temperature dependent relaxation time constant and that above T
D, the dynamic behavior is governed by two oscillators, one of which has a fast and temperature independent relaxation time constant and the other of which is a heavily damped oscillator with a slow and temperature dependent time constant. Furthermore a red shifting of the characteristic frequency of the damped oscillator was observed, confirming the presence of a non-harmonic vibration potential. Our measurements and modeling of GP2 highlight the unique capabilities of THz spectroscopy for protein characterization. 相似文献