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Objective: To explore the protective effect of human urine‐derived stem cell exosomes (hUSC‐Exos) on radiation‐induced salivary gland (SG) injuries in Sprague Dawley rats. Methods: Fresh adult urine was collected, and primary hUSCs were isolated and identified. The hUSCs were hypoxia‐pretreated with 1% oxygen for 24 h and then transferred to a normoxic culture environment for 24 h. The hUSC‐Exos were collected and identified for exosomes. A radiation‐induced injury model was established in the rats, and exosomes were introduced by local injection in the SG and tail vein. The submandibular gland was excised for morphological observation 1 week later. Immunohistochemical detection of the glandular tissue was conducted by α‐smooth muscle actin (a‐SMA), stem cell growth factor receptor (c‐Kit) staining, and periodic acid–Schiff staining. Qualitative polymerase chain reaction and western blot analysis were adopted to detect the gene and protein expression of Wnt3a, GSK3β, and Axin. Results: In both the normoxic and hypoxic hUSC‐Exo groups, microvesicular structures with bilayer membranes of approximately 80 nm in diameter were detected, and the expressions of CD9 and CD63 were detected by nanoflow cytometry. Compared with the control group, in the radiation‐induced injury model group, the expression of a‐SMA was significantly higher, the expression of c‐Kit was significantly lower, and the expressions of Wnt3a, GSK3β, and Axin were significantly upregulated; the differences were statistically significant (p < 0.05). Compared with the model group, in the normoxic and hypoxic hUSC‐Exo groups, the expression of a‐SMA was significantly decreased, the expression of c‐Kit was significantly increased, and the expressions of Wnt3a, GSK3β, and Axin were significantly upregulated; the differences were statistically significant (p < 0.05). Conclusion: Hypoxia‐pretreated hUSC‐Exos could repair radiation‐induced SG injuries by activating the Wnt3a/GSK3β pathway to suppress the expressions of a‐SMA and c‐Kit. [ABSTRACT FROM AUTHOR]

The construction industry has a high correlation with the regional economic development. With the development of regional economy, more and more industries show the characteristics of high influence, multi-power driven and high disparities. By considering the correlation of regional economy and the construction industry development, this paper establishes a dynamic evaluation indicator system for assessing development competitiveness of regional construction industry from the aspects of internal and external factors. This indicator system dynamically evaluates and hierarchically order the competitiveness of regional construction industry from a temporal perspective based on sequential global principal components analysis and hierarchical cluster analysis. The results show that the source of development competitiveness of construction industry are different and dynamic in different provinces. Besides the size of the construction, the competitiveness indicator is also closely related to the regional economic and social development level. The paper puts forward suggestions to improve the construction industry development by considering the disparities in the construction industry competitiveness. [ABSTRACT FROM AUTHOR]

It is the goal of protected area management to make full use of limited resources to better protect biodiversity. Currently, the main tasks of developing national park system in China are to combine conservation features, optimize the spatial network of protected areas, and identify the prio-rity conservation areas of national parks effectively. In this study, we assessed the spatial distribution of key ecosystem services (carbon sequestration, oxygen release, hydrological regulation, water resources, and soil retention) using ecological model, and simulated the distribution of suitable habitats for 37 endangered species by MaxEnt in Lishui City, Zhejiang Province. The irreplaceability index of each planning unit in Lishui was calculated on the 0.4 km×0.4 km grid using the systema-tic conservation planning model (MARXAN), setting key ecosystem services and endangered species as the conservation objects. Combined with the local management needs, the priority protection areas of national parks were identified comprehensively. The results showed that during 2005 to 2015, the annual carbon storage, oxygen release, hydrological regulation, water resource, and soil retention in the study area was 0.05 kg C·m -2 ·a -1 , 0.13 kg O 2 ·m -2 ·a -1 , 83.25×10 8 m 3 ·a -1 , 803 mm·a -1 , and 95.53 t·hm -2 ·a -1 , respectively. The irreplaceability index of different land use types was significantly different. The irreplaceability index of forest, river and reservoir, garden, cultivated land, residential land was 50-100, 60-100, 30-50, 15-35, 0-25, respectively. The priority conservation areas accounted for 11.8% of the study area. This study put forward a systematic conservation planning idea combining biodiversity and ecosystem services, which could provide a useful framework and technical support for optimizing the network layout of protected areas and priority conservation areas of national parks, and help to enhance the overall effectiveness of the establishment of the protected areas system with national parks as its main type in China.

Objective: This study aimed to investigate the therapeutic efficacy of paclitaxel in combination with carboplatin in different ways in rabbits with VX-2 tongue cancer., Methods: Rabbit VX-2 tongue cancer model was established and animals were then divided into 6 groups, in which animals received perfusion with paclitaxel liposome and carboplatin via the lingual artery, with free paclitaxel and carboplatin via the lingual artery, with 5% glucose via the lingual artery, with paclitaxel liposome and carboplatin via ear vein, with free paclitaxel and carboplatin via the ear vein and with 5% glucose via the ear vein independently. When the maximum diameter of cervical lymph nodes was larger than 5 mm, chemotherapy was initiated. Seven days later, flow cytometry and immunohistochemistry were performed to detect the apoptosis of VX-2 cells and P53 expression in the primary cancer and metastatic lymph nodes., Results: Targeted arterial perfusion with paclitaxel liposome in combination with carboplatin was more effective to induce the apoptosis of cancer cells in the primary cancer and metastatic lymph nodes and inhibit their proliferation., Conclusion: Targeted arterial perfusion with paclitaxel liposome in combination with carboplatin is effective to reduce tumor size, attenuate the surgery induced injury and improve the post-operative quality of life of oral cancer patients.

This study aimed to investigate the functional restoration of radiation-damaged salivary gland with human amniotic epithelial cells (hAECs) transplantation by intra-glandular injection. hAECs were isolated from the amnion tissues. After primary culture, the phenotype of hAECs of the second passage was identified by flow cytometry (FCM) and immunocytochemical staining. Then, hAECs were intra-glandularly injected into the irradiated glands of mice. At different time points after transplantation, the glands were collected for hematoxylin-eosin (HE) staining and immunofluorescence staining, and the saliva flow rate was also determined. Results showed these cells were positive for CD29, CD73 and CK19 and negative for CD44, CD34, CD45 and CD71. The transplanted hAECs in the recipient glands could differentiate into acinar-like cells and resulted in morphological and functional restoration of salivary gland.