Search

BACKGROUND: Studies have found that human dental pulp stem cells can treat periapical periodontitis bone defects under hypoxia preconditioning, but whether dental pulp stem cell exosomes under hypoxia preconditioning can carry the biological information of blasts and affect polarization of macrophages is unclear. OBJECTIVE: To study the effect of hypoxia-treated dental pulp stem cells exosomes on macrophage polarization. METHODS: Passage 3 dental pulp stem cells were cultured in a normal and hypoxic incubator. The medium was replaced once every 48 hours. Cell culture supernatants were collected at the confluence of 80%-90%. Exosomes were extracted by differential centrifugation. Human monocyte cell line THP-1 was induced to differentiate into macrophages, and co-incubated with PBS, normal culture, and hypoxic cultured dental pulp stem cells for 48 hours. Levels of inflammatory factors interleukin 10 and tumor necrosis factor alpha in supernatant were detected using ELISA. RT-qPCR was utilized to detect macrophage CD163, interleukin 1 receptor antagonist, transforming growth factor β1, chemokine CCL2, and tumor necrosis factor α mRNA expression. Flow cytometry was utilized to detect the expression of CD11b+CD163+ macrophages. Western blot assay was used to detect the activation of NF-κB and STAT3 signaling pathways. RESULTS AND CONCLUSION: (1) Compared with the PBS group, the level of interleukin-10 in the supernatant of macrophages in the normal cultured dental pulp stem cell-derived exosomes group significantly increased (P < 0.05), and the level of tumor necrosis factor alpha significantly reduced (P < 0.05). The expression of CD163, transforming growth factor β1, and chemokine CCL2 mRNA in macrophages increased significantly (P < 0.05); the expression of tumor necrosis factor alpha mRNA decreased significantly (P < 0.05), and the positive rate of CD11b+CD163+ macrophages increased significantly (P < 0.05); the phosphorylation level of p65 significantly reduced (P < 0.05); the expression of IκBα significantly increased (P < 0.05), and the phosphorylation level of STAT3 also significantly increased (P < 0.001). (2) Compared with the normal cultured dental pulp stem cell-derived exosomes group, the level of interleukin-10 in the supernatant of macrophages significantly increased in the hypoxic cultured dental pulp stem cell-derived exosomes group (P < 0.001), and the level of tumor necrosis factor alpha significantly reduced (P < 0.01); CD163, transforming growth factor β1, chemokine CCL2 and interleukin 1 receptor antagonist mRNA expression significantly increased (P < 0.01); tumor necrosis factor alpha mRNA expression also significantly decreased (P < 0.01); the positive rate of CD11b+CD163+ macrophages significantly increased (P < 0.01); the phosphorylation level of p65 significantly reduced (P < 0.01); the expression of IκBα significantly increased (P < 0.01), and the phosphorylation level of STAT3 significantly increased (P < 0.01). (3) It is concluded that normal culture and hypoxic culture of exosomes derived from dental pulp stem cells can promote the M2 polarization of macrophages, and the M2 polarization of macrophages is more obvious under hypoxic culture, and its mechanism may be to activate the STAT3 signaling pathway and inhibit the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Aimed at the problems of poor foundation anti-scourability and lack of local stone in the closure of lock dam in soft foundation river bed, the technical scheme of net cage mixed closure was put forward. The first step was to dump sand bags and consolidate through natural settlement for bottom protecting. Then the net cage composed of pile and bamboo grid was built along both sides of the axis of lock dam. Finally the closure was realized by manually throwing sand bag in the net cage. The key technologies, such as the basic platform construction, the geotextile laying under dynamic water condition, wrap-head connection and air-closure were solved. The closure was carried out by three phases. In the first stage, sand bags were dumped into the original river bed to fill the closure foundation platform, so that the soft foundation of riverbed was squeezed and consolidated to form a first-class underwater sand-bag dam. In the second stage, the foundation platform was protected against erosion by geotextile, the wrap-head was built and the berm connected with both banks was filled and the air-closure was completed in the dry season. In the third stage, the overall structure of the net cage was adopted to implement vertical closure and air-closure. The scheme has a good technical economy for the soft foundation closure project in stone deficient areas. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nursing of Integrated Traditional Chinese & Western Medicine is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nursing of Integrated Traditional Chinese & Western Medicine is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nursing of Integrated Traditional Chinese & Western Medicine is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the development of deepwater gas field, ethylene glycol is commonly used as hydrate inhibitor. Large amounts of salt contained in produced water caused scaling in the treatment of rich glycol liquid with high salt in common ethylene glycol regeneration system,which has serious impact to the offshore production system, even lead to suspend production. Therefore, the process of salt removal from ethylene glycol is supposed to be one part of ethylene glycol regeneration system for deepwater gas production. Models of the process of high solubility salt removal from ethylene glycol have been developed in process simulation program Aspen Plus, through which the effect of recycle temperature, ethylene glycol recycle flow rate, and water content of ethylene glycol on the salt removal process have been simulated and analyzed. The results showed that the salt removal process made a good performance with appropriate process parameters such as the flash pressure（absolute） of 0.15 MPa, the recycle heated temperature of 141~145 ℃, and the recycle flow rate is 60 times of the feed rate. [ABSTRACT FROM AUTHOR]

Copyright of Nursing of Integrated Traditional Chinese & Western Medicine is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)