Objective To conduct the preliminary toxicology tests and evaluate the preservation effect on a new specimen preservation solution in order to provide scientific basis for its application security. Methods Twenty-four New Zealand white rabbits were randomly di-vided into the normal saline group, the formalin preservation group,the mixture group,and the new preservation solution group. Recorded the irritation of different solution on the skin,eye of rabbits,the effect of liver sample preservation in different solution,and the evaporation rate of these solution. And to find a set of preservative solution which is more suitable for preservation of specimens and can reduce the cost. Results The new preservation solution is stimulus on rabbit skin and eye,and it is stronger than the formaldehyde group. Compared with the other three groups,the mixture group has the best preservation effect, and the new preservation solution group has a better preservation effect than the formalin preservation solution group. Conclusion The 1∶1 mixture solution of the new preservation solution and formaldehyde is more suitable preservation solution and it can reduce the costs.

BACKGROUND:MXene nanoparticles have considerable application prospects as effective functional components of skin wound dressings due to their unique properties of conductivity,hydrophilicity,antibacterial activity,and biocompatibility. OBJECTIVE:To review the synthesis methods,functional properties,and application of MXene nanoparticles in skin injury repair. METHODS:"MXene,nanoparticles,nanomaterials,bioactive nanoparticles","wound dressing,wound dressing,wound repair materials","wound repair,wound healing,wound surface"were used as Chinese search terms to search Wanfang and CNKI databases."MXene,nanoparticles,nano-materials,bioactive nanoparticles","wound dressing,wound healing material","wound healing,wound repair,wound"were used as English search terms to search the PubMed database.Finally,88 articles were included for review analysis. RESULTS AND CONCLUSION:(1)MXene synthesis can be divided into two methods:bottom-up synthesis and top-down synthesis.The synthesized MXene can be further modified to enhance biocompatibility for better application in biomedicine.(2)MXene has a series of excellent properties such as hydrophilicity,antibacterial,photothermal properties,electrical conductivity,and good biocompatibility,all of which make it the basis for excellent skin repair materials.(3)At present,many scholars have developed new composite materials for wound dressings.Currently,these composite materials are based on MXene nanomaterials and make full use of its excellent characteristics as mentioned above,which play a role in local skin wound sterilization,drug delivery,and sustained release,active regulation of cytokines,and can integrate the advantages of other biologically active agents.It plays a better role in wound healing,especially in the treatment of complex chronic wounds.(4)Various composite materials such as MXene@PVA hydrogel and MXene@CH sponge developed based on various properties of MXene have shown good effects on improving tissue repair performance and repairing skin damage as drug carriers.It shows that MXenes nanoparticles are in the initial stage of development and have great prospects in the field of promoting skin repair.The characteristics and surface modification of MXenes nanoparticles have been well studied,but the molecular mechanism of dose-dependent biotoxicity is relatively incomplete.

Objective To investigate the transport and deposition behaviors of lowdensity lipoproteins (LDL) in the carotid artery and explore their associations with hemodynamic and morphological factors, so as to provide theoretical references for assessing the risk and predisposing regions of atherosclerosis based on the characteristics and associated factors of LDL deposition at the carotid artery wall. Methods Subject-specific computational models of the carotid artery based on medical images from six healthy volunteers were built, and the transport and wall deposition of LDL under pulsatile flow conditions were simulated, and finally the correlations of wall LDL concentration and total area of regions with LDL concentration polarization with flow velocity and morphological parameters of the carotid artery were quantitatively analyzed. Results Regions with significant LDL deposition often appeared in carotid sinus near distal end of the common carotid artery, with the degree and spatial distribution of deposition differing considerably among subjects. The degree of LDL deposition was determined mainly by flow velocity, i.e., the lower the flow velocity was, the higher the degree of LDL deposition and accordingly the larger the area of wall regions with LDL concentration polarization was; whereas the spatial distribution of LDL deposition was significantly affected by morphological characteristics (especially bifurcation eccentricity ratio) of the carotid artery, for example, the distribution patterns could be divided into two typical types (i.e., circular distribution, unilateral distribution) according to bifurcation eccentricity ratio. Conclusions Flow velocity and morphological characteristics of the carotid artery are major factors determining respectively the degree and spatial distribution of LDL deposition, and therefore subject-specifically measuring these parameters will provide useful information for screening individuals at high risk of atherosclerosis or identifying atheroprone regions.