The results indicate that two benzodioxole derivatives, piperonyl alcohol (PAL) and benzodioxole (BDO), are viable alternatives to conventional amines as coinitiator. The biocompatibility of benzodioxole derivatives makes them more promising than amine in dental resin formulations.

Synthesized 4-benzophenone methoxyl methacrylate (BMM) was used as a polymerizable photoinitiator in combination with 2-(N,N-dimethylamino) ethylmethacrylate (DMEM) to initiate the UV photopolymerization of the mixture of 70 wt % 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]-propane (Bis-GMA) and 30 wt % triethylene glycol dimethylacrylate (TEGDMA). Real time infrared spectroscopy (RTIR) was used to monitor the extent of polymerization and dynamic mechanical analyzer (DMA) was used to measure the mechanical properties of the cured samples. Water sorption and solubility of cured samples were tested according to ISO4049's standards. The obtained results indicated that increasing the concentration of DMEM or BMM led to the increase of double bond conversion and the rate of polymerization. Comparing with the non-polymerizable photoinitiating system in the same curing condition, benzophenone(BP)/ethyl 4-dimethylaminobenzoate (EDMAB), BMM/DMEM showed the slightly higher initiating reactivity. The glass transition temperature (T g ), storage modulus, water sorption and solubility of the cured samples initiated by BMM/DMEM were slightly lower than that of samples initiated by BP/EDMAB. KEY WORDS: Polymerizable Photoinitiator / FT-IR / Kinetics / Photopolymerization / The technology of photoinduced polymerizations is widely used in several industrial fields. Important advantages offered by this technology such as high curing speed, reduced release of volatiles compounds because of no solvents, low cost of equipment, good mechanical properties, inertness to solvents and resistance to abrasion of the obtained polymer could be achieved through a high degree of cross-linking reaction.

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Millions of patients worldwide are affected by Alzheimer’s disease (AD), and the number of patients with AD is increasing. However, current treatment can only improve symptoms but cannot cure the disease. Astrocytes, glial cells in the central nervous system, play important roles in support, nutrition, protection, and information transmission in the nervous system. Pathological changes in astrocytes are closely associated with the development and progression of AD. As carriers for material and information exchange between astrocytes and other neural cells, astrocyte-derived exosomes (ADEs) have been widely studied in recent years, and ADE secretion has been shown to be increased in patients with AD and animal models of AD. ADEs contain a variety of substances, including nucleic acids, proteins, and lipids. The contents of ADEs can effectively control oxidative stress and detoxification during the early development of AD, thereby playing positive and negative roles in the occurrence and development of AD. In this review, we elaborate on the functions of ADEs and their components in AD and discuss their applications in AD research and clinical practice.

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