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Pectic oligosaccharides (POS), small molecular polymers, can be prepared from pectin by different methods. Compared with natural pectin, POS have lower molecular mass, better water solubility, higher bioavailability, and more diverse biological activities. A series of POS with different molecular masses and structures can be obtained under different preparation conditions. In addition, the biological activities of POS are closely related to their molecular mass and structures. This review aims to comprehensively summarize the preparation, purification, structure analysis, and biological activity of POS, in order to provide some references for their applications as natural active substances in the fields of food, medicine, and health products.

Summary: The comprehensive utilisation of food waste has become a global development demand for enhancing their added value. This study aimed to develop and utilise physiological fruit drop of Citrus aurantium L. var Daidai with rich phenolic acids and flavonoids. Therefore, different concentrations (1%, 3%, 5%, 10% wt, based on pullulan weight) of daidai physiological fruit drop extracts (DE) were incorporated into pullulan/bacterial cellulose (BC) packaging film (PB2‐DE). The effects of different concentrations of DE on composite films were comprehensively evaluated. It was found that the mechanical properties, ultraviolet barrier properties, and antioxidant properties of the films were improved with the addition of DE. Moreover, application tests have verified that films containing DE can effectively maintain the attractive quality of strawberries. Conclusively, the results demonstrated the feasibility of DE incorporation into films to increase the value of the waste and the potential applicability of films containing DE in strawberry preservation. [ABSTRACT FROM AUTHOR]

Amiloride-sensitive epithelial sodium channel (ENaC) is a major sodium channel in the lung facilitating fluid absorption. ENaC is composed of [alpha], [beta]-, and [gamma]-subunits, and the ct-subunit is indispensable for ENaC function in the lung. In human lungs, the a-subunit is expressed as various splice variants. Among them, [[alpha].sub.1]- and [[alpha].sub.2]-subunits are two major variants with different upstream regulatory sequences that possess similar channel characteristics when tested in Xenopus oocytes. Despite the importance of [alpha]-ENaC, little was known about the relative abundance of its variants in lung epithelial cells. Furthermore, lung infection and inflammation are often accompanied by reduced [alpha]-ENaC expression. oxidative stress, and pulmonary edema. However, it was not clear how oxidative stress affects expression of [alpha]-ENaC variants. In this study, we examined relative expression levels of [alpha]-subunit variants in four human lung epithelial cell lines. We also tested the hypothesis that oxidative stress inhibits [alpha]-ENaC expression. Our results show that both [[alpha].sub.1]- and [[alpha].sub.2]-ENaC variants are expressed in the cells we tested, but relative abundance varies. In the two monolayer-forming cell lines, H441 and Calu-3, [[alpha].sub.2]-ENaC is the predominant variant. We also show that [H.sub.2][O.sub.2] specifically suppresses [[alpha].sub.1]- and [[alpha].sub.2]-ENaC variant expression in H441 and Calu-3 cells in a dose-dependent fashion. This suppression is achieved by inhibition of their promoters and is attenuated by dexamethasone. These data demonstrate the importance of the [[alpha].sub.2]-subunit variant and suggest that glucocorticoids and antioxidants may be useful in correcting infection/inflammation-induced lung fluid imbalance. ion channel; steroids; transcription; promoter; splice variant

Vimentin is one of the mammalian intermediate filament proteins. It is expressed in cells of mesenchymal origin and is characteristic of proliferating cells at the fetal stage. During malignancy, vimentin expression is activated in certain lung epithelial cells. Examination of a group of lung cancer cells showed a marked difference in their vimentin expression. The difference in vimentin expression among lung cancer cells is due to differential regulation at the transcriptional level. Analysis of the vimentin promoter revealed a 102-bp promoter sequence that is important for promoter activity in a lung cancer cell line in which vimentin is strongly expressed. This promoter region interacts with poly(ADP-ribose) polymerase-1 (PARP-1), which is also a transcription regulator. Exogenous expression of PARP-1 increased vimentin promoter activity. A shortened PARP-1 without the COOH-terminal catalytic domain showed the same promoter activation effect. Treatment of cells with [H.sub.2][O.sub.2] reduced PARP-1 and vimentin expression at the protein level. [H.sub.2][O.sub.2] also dose dependently suppressed vimentin promoter activity in cells overexpressing PARP-1. These results demonstrate that vimentin expression in lung cancer cells is regulated at the transcriptional level and that PARP-1 binds and activates the vimentin promoter independent of its catalytic domain and may play a role in [H.sub.2][O.sub.2]-induced inhibition of vimentin expression. hydrogen peroxide; promoter; lung epithelia; catalytic domain