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Mussel adhesive proteins (MAPs) have a unique ability to firmly adhere to different surfaces in aqueous environments via the special amino acid, 3,4-dihydroxyphenylalanine (DOPA). The catechol groups in DOPA are a key group for adhesive proteins, which is highly informative for the biomedical domain. By simulating MAPs, medical products can be developed for tissue adhesion, drug delivery, and wound healing. Hydrogel is a common formulation that is highly adaptable to numerous medical applications. Based on a discussion of the adhesion mechanism of MAPs, this paper reviews the formation and adhesion mechanism of catechol-functionalized hydrogels, types of hydrogels and main factors affecting adhesion, and medical applications of hydrogels, and future the development of catechol-functionalized hydrogels.

Based on the field survey of the second floor and the fifth floor of Yingxian Wood Pagoda, a comparative analysis of the damage conditions of the transverse compression members-Pupaifang, flower arm, and axial bracket arm on each hypostyle corner column was made in this paper, and the crack rate was measured using ImageJ to study cracking degree and distribution law of the transverse compression members of each layer. The results showed that the transverse compression cracking of Pupaifang of the second floor was serious, with the average crack rate of 16.6%. Most of the end faces were in the form of spallation, and even the brace body had the phenomenon of complete collapse and partial fall off. The average compression crack rate of the transverse compression of flower arm and axial bracket arm were 7.7% and 12.0%, respectively, and the arch body had the phenomenon of partial peeling and breaking. The transverse compression failure of Pupaifang, flower arm, and axial bracket arm of the fifth layer was mainly minor cracks, with the average crack rate of 2.9%, 2.6%, and 2.1% respectively, and the degree of cracking was relatively moderate. For the cracking distribution of the twostorey transverse grain compression member, the second floor mostly appeared in the southwest and northeast of the tower, while the cracking distribution of the fifth floor transverse grain compression member was more uniform. The method used in this study can effectively obtain the transverse compressive damage status and crack distribution of the internal components of Yingxian wooden tower, providing a certain foundation for future repair and protection work of wood pagoda. [ABSTRACT FROM AUTHOR]

In this study, the porous composite films of carboxymethyl chitosan/alginate/tranexamic acid were fabricated, with calcium chloride as the crosslinking agent and glycerin as a plasticizer. The composite films were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The properties of the composite films, including water absorption, air permeability, and cumulative release rate, were tested. In addition, their hemostatic performance was evaluated. The results showed that the appearance of the films with good adhesion was smooth and porous. FTIR showed that chemical crosslinking between carboxymethyl chitosan and sodium alginate was successful. The excellent cumulative release of tranexamic acid in the composite films (60–80%) gives the films a significant procoagulant effect. This has good prospects for the development of medical hemostasis materials.

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.

Chitosan oligosaccharide (COS), a natural polysaccharide with good antioxidant and anti-inflammatory properties, is the depolymerized product of chitosan possessing various biological activities. The present study was designed to investigate the possible anti-aging effect of COS on the aging model mouse induced by d-galactose (d-gal) and explore the underlying mechanism. In the experiment, 48 male Kunming mice (KM mice) were randomly divided into the normal group, model group, positive group, and low-medium-high dose polysaccharide groups (300, 600, 1200 mg/kg/day). The results showed that COS, by intragastric gavage after subcutaneous injection of d-gal (250 mg/kg/day) into the neck of mice consecutively for eight weeks, gradually recovered the body weight, the activity of daily living, and organ indices of mice, as well as effectively ameliorated the histological deterioration of the liver and kidney in mice triggered by d-gal. To be specific, COS obviously improved the activities of antioxidant enzymes in liver and kidney of KM mice, including catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD), as well as decreased malondialdehyde (MDA) levels when compared with those in model group mice. Furthermore, COS not only elevated the diminished levels of serum immunoglobulin G (IgG) and IgM induced by d-gal, but also significantly inhibited the d-gal-caused upregulation of serum alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), uric acid (UA) and creatinine (CREA) levels as compared with those of mice in the model group. These results demonstrate that COS has an obvious anti-aging activity in d-gal-induced subacute aging mice, the mechanism of which, to some extent, is associated with enhancing the antioxidant defenses, reducing oxidative stress, and improving the immune function of aging model mice.

To solve the problem of inefficient transmission using multiple interfaces of multihome terminal in the tradition network,an end-to-end multipath transport layer architecture—E2EMP oriented the next generation network was presented.Through distributing data adaptively following characters of the end-to-end paths,adopting dual sequence space,implementing smart path management policies,the performance of the multihome terminal using E2EMP has significant improvement.The simulation results show that E2EMP aggregates bandwidth of the multihome terminal interfaces efficiently,and meanwhile promotes the security and reliability of end-to-end multipath transport.

Aiming at dense wireless sensor networks with a path-constrained mobile sink, an optimized partition scheme of sub-sinks’ overlapping time was proposed based on data equilibrium.And a two-phase communication protocol was designed to effectively control the amount of data generated by each node through diffusion of the data equilibrium in-formation.Simulation experiments show that the proposed protocol and algorithms outperform other conventional methods in terms of data equilibrium rate, network lifetime.

Connecting wireless sensor networks （WSN） with Internet and providing effective services to the Internet us-ers are the heated research issues. The architecture of connecting WSN with Internet was proposed,Internet-WSN gate to realize the data-package transmission between WSN and Internet was designed. The methods of providing services were presented with the thought of network middleware. The analysis and the comparison show that the architecture presented solves the problem of connecting WSN with Internet from two levels: networks and services. This architecture has the advantages of corresponding with the network protocols available,transparent for users,simultaneously connecting sev-eral WSN with Internet,low cost and conveniently offering services.

The architectures of publish/subscribe communication systems and various routing mechanisms and algorithms were discussed and reviewed,including the basic methods of finding communication objects,routes optimization and routes for supporting topology change and client mobile,etc; The routing methods of famous P/S systems were compared and analyzed; On the perspective of the system scalability,the direction of further research was proposed finally.

Background: In previous studies, both 17β-estradiol (E2) and resveratrol (RES) were reported to protect intervertebral disc cells against aberrant apoptosis. Given that E2 has a better anti-apoptotic effect with more cancer risk and RES has an anti-apoptotic effect with less cancer risk, the combined use of E2 with RES is promising in developing clinical therapies to treat apoptosis-related diseases such as intervertebral disc degeneration in the future. Objective: The purpose of this study was to explore the combined effect of E2 with RES on rat nucleus pulposus cells and the underlying mechanisms. Methods: TUNEL assay and FACS analysis were used to determine apoptotic incidence of nucleus pulposus cells. MTS assay was used to determine cell viability, and cellular binding assay was used to determine cell-ECM (extracellular matrix) ability. Real-time quantitative RT-PCR was to determine mRNA level of target genes. And Western blot was used to determine the protein level. Results: Both E2 and RES decreased apoptotic incidence when used singly; interestingly, they decreased apoptosis more efficiently when used combinedly. Meanwhile, E2 and RES combined together against the decrease of cell viability and binding ability resulting from IL-1β cytotoxicity. As well, activated caspase-3 was suppressed by the combined effect. Furthermore, IL-1β downregulated expression level of type II collagen and aggrecan (standing for anabolism), while upregulated MMP-3 and MMP-13 (standing for catabolism). However, the combined use of E2 with RES effectively abolished the above negative effects caused by IL-1β, better than either single use. Finally, it turned out to be that E2 and RES combined together against apoptosis via the activation of PI3K/Akt/caspase-3 pathway. Conclusion: This study presented that IL-1β induced aberrant apoptosis, which was efficiently resisted by the combined use of E2 with RES via PI3K/Akt/caspase-3 pathway.