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Jin Wang,1,2 Ye Qian,2 Xuemin Gao,3 Na Mao,3 Yucong Geng,4 Gaojie Lin,3 Guibin Zhang,2 Han Li,3 Fang Yang,3 Hong Xu3 1Department of Clinical Laboratory, Qingpu Branch of Zhongshan Hospital, Fudan University, Shanghai 201700, People’s Republic of China; 2Hebei Key Laboratory for Chronic Diseases, Tangshan Key Laboratory for Preclinical and Basic Research on Chronic Diseases, School of Basic Medical Sciences, North China University of Science and Technology, Tangshan, Hebei 063210, People’s Republic of China; 3Medical Research Center, International Science and Technology Cooperation Base of Geriatric Medicine, North China University of Science and Technology, Tangshan, Hebei 063210, People’s Republic of China; 4Department of Pathology, Haigang Hospital of Qinhuangdao, Qinhuangdao, Hebei, 066000, People’s Republic of ChinaCorrespondence: Hong XuMedical Research Center, International Science and Technology Cooperation Base of Geriatric Medicine, North China University of Science and Technology, Tangshan, Hebei 063210, People’s Republic of ChinaTel +86-315-8816236Fax +86-315-8816238; Email xuhong@ncst.edu.cnBackground: N-Acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a short peptide with an anti-silicosis effect. However, the short biological half-life and low plasma concentration of Ac-SDKP hamper discovery of specific targets in organisms and reduce the anti-silicosis effect. A novel peptide, Ac-SDK (biotin) proline, termed “Ac-B”, with anti-fibrotic properties was synthesized.Methods: Ac-B was detected quantitatively by high-performance liquid chromatography. Phagocytosis of Ac-B by the alveolar epithelial cell line A549 was investigated by confocal laser scanning microscopy and flow cytometry. To further elucidate the cellular-uptake mechanism of Ac-B, chemical inhibitors of specific uptake pathways were used. After stimulation with transforming growth factor-β 1, the effects of Ac-B on expression of the myofibroblast marker vimentin and accumulation of collagen type I in A549 cells were analyzed by Western blotting. Sirius Red staining and immunohistochemical analyses of the effect of Ac-B on expression of α-smooth muscle actin (SMA) in a rat model of silicosis were undertaken.Results: Ac-B had good traceability during the uptake, entry, and distribution in cells. Ac-B treatment prevented an increase in α-SMA expression in vivo and in vitro and was superior to that of Ac-SDKP. Caveolae-mediated uptake of Ac-B by A549 cells led to achieving anti-epithelial–mesenchymal transformation (EMT) effects.Conclusion: Ac-B had an anti-fibrotic effect and could be a promising agent for the fibrosis observed in silicosis in the future.Keywords: Ac-SDKP, biotin, epithelial–mesenchymal transformation, phagocytosis, anti-fibrotic function

Climate change is a global threat to food security as it causes various biotic and abiotic stresses that adversely disturb agriculture production. With an increase in the worldwide population, the demand for food has also arisen. It is an immediate challenge for the scientific community to introduce an innovative tool to achieve food security with quality plant production and develop tolerance against abiotic stresses, specifically drought. Genetically modifications are effective and time-consuming, while biostimulants are in/organic substances with the potential to support plant development under stress conditions. This chapter focuses on the impacts of climate change on agriculture, challenges for agriculture sustainability and food security, the interrelationship between drought, climate change and food security, the potential role of biostimulants against drought, future aspects and challenges due to climate change specifically drought, and food security challenges. Various studies reported that the application of biostimulants results in enhancement of crop productivity and mitigates the harmful effects due to climate change. To ensure the quality of chapter, we collected references from well-reputed international journals using keywords ““biostimulants,” “drought,” “food security,” “agriculture sustainability,” and “climate change.” In conclusion, biostimulants has a potential to address adverse environmental conditions without affecting crop quality and yield loss.

Silicosis is the most common occupational lung disease in China, and is associated with a variety of complications, many of which are poorly understood. For example, recent data indicate that silicosis associates with the development of osteopenia, and in some cases this bone loss is severe, meeting criteria for osteoporosis. Although many factors are likely to contribute to this relationship, including a sedentary lifestyle in patients with advanced silicotic lung disease, we hypothesized that silica might directly reduce bone mineral density. In the present study, six Wistar rats were exposed to silica for 24 weeks in order to induce pulmonary silicosis and examine the relationship to bone mineral density. As expected, all rats exposed to silica developed severe pulmonary fibrosis, as manifested by the formation of innumerable silicotic nodules and the deposition of large amounts of interstitial collagen. Moreover, micro-CT results showed that bone mineral density (BMD) was also significantly reduced in rats exposed to silica when compared control animals and this associated with a modest reduction in serum calcium and 25-hydroxyvitamin D levels. In addition, we found that decreased BMD was also linked to increased osteoclast activity as well as fibrosis-like changes, and to the deposition of silica within bone marrow. In summary, our findings support the hypothesis that silicosis reduces bone mineral density and provide support for ongoing investigations into the mechanisms causing osteopenia in silicosis patients.