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Solketal is an important chemical product with widespread applications, and the raw materials glycerol and acetone are inexpensive, making it highly economically viable. The glycerol-acetone condensation reaction is a typical acid-catalyzed reaction. Traditional homogeneous acidic catalysts cause significant environmental pollution and are difficult to recover. Herein, PEG-800 was used as an additive, and a one-pot process was employed to prepare a series of aluminum phosphate catalysts (xP-Al-O) with different P/Al molar ratios. The physical and chemical properties of the prepared xP-Al-O catalysts were thoroughly investigated using XRD, FTIR, SEM, Py-FTIR, BET, and NH3 (CO2)-TPD methods. The results indicated that different P/Al molar ratios indeed affect the catalyst structure, and all prepared xP-Al-O samples exist in the form of amorphous aluminum phosphate, with weak acidic sites dominating the surface. The prepared catalysts were investigated for their catalytic behavior in the acetalization reaction of glycerol and acetone. The 1.1P-Al-O catalyst exhibited the highest acetone glycerol acetal yield and demonstrated good catalytic stability.

SBA-15-supported Al 2 O 3 -P 2 O 5 with 10 wt% Al 2 O 3 and different P 2 O 5 mass percentages (10Al 2 O 3 - x P 2 O 5 /SBA-15) were prepared by simple impregnation method and used for gas-phase selective O-methylation of catechol to guaiacol with dimethyl carbonate. The 10Al 2 O 3 - x P 2 O 5 /SBA-15 catalysts maintained ordered mesoporous structures, but their specific surface areas, pore volumes, and pores decreased with the addition of Al and P oxides. The addition of P 2 O 5 decreased the strength of weak acid, but with the P 2 O 5 content increasing, the additional pseudo-bridging bonds that are similar to amorphous silica-alumina were formed, which enhanced the acidity of weak acid. Brønsted acid sites introduced by P 2 O 5 promoted more acid sites and lower the strength of acid sites. The basic sites increased with the increase of P 2 O 5 content. Acidic sites are the key to control the catalytic activity, and basic sites are the key to control the catalytic selectivity. 10Al 2 O 3 -5P 2 O 5 /SBA-15 exhibited excellent catalytic activities and high selectivity to guaiacol for the O-methylation of catechol, due to the synergistic effect of acid and base sites.

A series of Al-P-O catalysts (Al-xP-O) were prepared using a P123-assisted one-pot method at different P/Al molar ratios and used for O-methylation of catechol and methanol. The influences of the P/Al molar ratio and P123 addition on catalyst structure and surface acid-base characteristics were investigated in detail. Increasing the P/Al molar ratio more favored crystalline aluminophosphate. The P123-assisted Al3+ and PO43− are known to be stabilized through weak steric force so that the formation of crystalline aluminophosphate could be inhibited at higher P/Al molar ratios. The results showed that the prepared Al-P-O catalysts possessed appropriate weak acid and weak base sites, which was beneficial to the reaction of catechol and methanol. The Al-1.1P-O catalyst synthesized with the assistance of P123 exhibited superior catalytic performances, with 52.5% catechol conversion and higher guaiacol selectivity of 97.6%.

Effect of tacrolimus on atherosclerotic plaques and its influence on Nod-like receptor protein 3 (NLRP3) inflammatory pathway were studied by establishing the mouse model of atherosclerosis. The mice were divided into 3 groups: C57BL/6 mouse group (WT group), ApoE−/− mouse group (ApoE−/− group) and ApoE−/− mouse + tacrolimus intervention group (ApoE−/− + Tac group). The area of atherosclerotic plaques and the pathological morphologic changes were observed. The NLRP3, interleukin-1β (IL-1β), IL-18, NLRP3 inflammatory corpuscles, pro-inflammatory factors IL-1β and IL-18 in the aorta were analyzed. The area of atherosclerotic plaques in ApoE−/− mice was increased significantly, and it was significantly reduced after tacrolimus intervention. After tacrolimus intervention, the arterial intima became obviously thinner and no obvious cholesterol crystals were observed. The macrophage infiltration in atherosclerotic plaques was significantly increased, and the content of smooth muscle cells was also increased. The levels of serum IL-1β, IL-18 and NLRP3 in ApoE−/− mice were significantly increased, and they remarkably declined after tacrolimus intervention. ROS content in atherosclerotic plaques was increased in ApoE−/− mice, and it remarkably declined after tacrolimus intervention. The protein content of NLRP3, ASC, Casp-1, IL-1β and IL-18 in the aorta in ApoE−/− mice was remarkably increased, and they were inhibited to some extent after tacrolimus intervention. In conclusion, it is speculated that tacrolimus may reduce the formation of AS through inhibiting ROS in macrophages and activation of NLRP3 inflammatory corpuscles and reducing the release of IL-1β and IL-18.

Effect of tacrolimus on atherosclerotic plaques and its influence on Nod-like receptor protein 3 (NLRP3) inflammatory pathway were studied by establishing the mouse model of atherosclerosis. The mice were divided into 3 groups: C57BL/6 mouse group (WT group), [ApoE.sup.-/-] mouse group ([ApoE.sup.-/-] group) and [ApoE.sup.-/-] mouse + tacrolimus intervention group ([ApoE.sup.-/-] + Tac group). The area of atherosclerotic plaques and the pathological morphologic changes were observed. The NLRP3, interleukin-1[beta] (IL-1[beta]), IL-18, NLRP3 inflammatory corpuscles, pro-inflammatory factors IL-1[beta] and IL-18 in the aorta were analyzed. The area of atherosclerotic plaques in [ApoE.sup.-/-] mice was increased significantly, and it was significantly reduced after tacrolimus intervention. After tacrolimus intervention, the arterial intima became obviously thinner and no obvious cholesterol crystals were observed. The macrophage infiltration in atherosclerotic plaques was significantly increased, and the content of smooth muscle cells was also increased. The levels of serum IL-1[beta], IL-18 and NLRP3 in [ApoE.sup.-/-] mice were significantly increased, and they remarkably declined after tacrolimus intervention. ROS content in atherosclerotic plaques was increased in [ApoE.sup.-/-] mice, and it remarkably declined after tacrolimus intervention. The protein content of NLRP3, ASC, Casp-1, IL-1[beta] and IL-18 in the aorta in [ApoE.sup.-/-] mice was remarkably increased, and they were inhibited to some extent after tacrolimus intervention. In conclusion, it is speculated that tacrolimus may reduce the formation of AS through inhibiting ROS in macrophages and activation of NLRP3 inflammatory corpuscles and reducing the release of IL-1[beta] and IL-18. Key words: tacrolimus, atherosclerosis, NLRP3, inflammation, ROS

Guaiacol produced by O-methylation of catechol with methanol over solid catalysts is a green environmental synthesis route. In order to achieve high catalytic efficiency, it is quite necessary to employ low-cost catalysts with high activity and stability. Herein, series of aluminophosphate catalysts were synthesized by a simple precipitation route modified by Zr. The characterization results indicated that the prepared Al-P-Zr catalysts possessed appropriate weak acid and weak base sites, which were beneficial for the O-methylation of catechol with methanol. Different Zr amount and calcined temperature exerted a significant influence on physicochemical properties of the catalysts and catalytic performance. The Al-P-Zr catalysts containing Zr/Al molar ratio of 0.012 calcined under 400 °C showed the optimal catalytic activity and long-term stability for vapor-phase selective O-methylation of catechol with methanol.

The O-methylation of catechol is an effective method for the industrial production of guaiacol used as an important chemical. However, the low catechol conversion and poor catalyst stability are the most critical issues that need to be addressed. Herein, the O-methylation of catechol with dimethyl carbonate was investigated over aluminophosphate (APO) catalysts, using a continuous-flow system to produce guaiacol. APO catalysts were synthesized with varying P/Al molar ratios and calcination temperatures to study their effects on catalytic performance for the reaction. The physico-chemical properties of the APO catalysts were thoroughly investigated using XRD, NH3-TPD, CO2-TPD, FTIR, and Py-FTIR. The P/Al molar ratio and catalyst calcination temperature significantly influenced the structure and texture, as well as the surface acid-base properties of APO. Both the medium acid and medium base sites were observed over APO catalysts, and the Lewis acid sites acted as the main active sites. The APO (P/Al = 0.7) exhibited the highest catalytic activity and excellent stability, due to the suitable medium acid-base pairs.

Mesoporous Ni–Al composite oxides (Ni x Al, x  = 0.05, 0.1, 0.125, 0.25, 0.5) with different Ni/Al molar ratio have been successfully prepared by partial hydrolysis of aqueous solution of Al(NO 3 ) 3 and Ni(NO 3 ) 2 with (NH 4 ) 2 CO 3 solution without templates or organic surfactants. The samples exhibit a wormhole-like mesoporous structures with large specific surface areas of 105–213 m 2 /g and narrow pore size distributions. With increasing Ni/Al molar ratio, BET surface areas decrease, while BJH pore diameters increase. Nickel species are highly dispersed in the alumina frameworks through the formation of Ni–Al composite oxides. The comparative investigation for the reforming of benzene over the prepared Ni 0.1 Al catalyst and the counterpart obtained by templating method reveals that prepared Ni 0.1 Al catalyst shows high stability and coke resistance ability because of the better mass transfer properties of the wormhole-like mesostructure.

Root resorption is a common side effect of orthodontic treatment. In the current study, lithium chloride (LiCl), a Wnt signaling activator, was examined to determine its effect on root resorption. In total, 10 Sprague Dawley rats were randomly allocated into the experimental group (EG) and control group (CG). Each group consisted of five subjects. By using closed nickel-titanium coil springs, a 50-g force was applied between the upper incisors and the maxillary right first molars in order to mimic orthodontic biomechanics in the EG and CG for 14 days. During the 14 days, the EG rats were gavage-fed 200 mg/kg LiCl every 48 h. Next, digital radiographs were captured using a micro-computational tomography scanner. The movement of the maxillary first molars and the root resorption area ratio were measured electronically on the digital radiographs. The outcomes were analyzed using ANOVA. Following 14 days of experimental force application, all rats had spaces of varying sizes between the first and second right maxillary molars. The average distance measured in the CG was slightly higher than in the EG, however, the difference was not found to be statistically significant (P=0.224). Root resorption craters were observed in the groups following the experiment. Rough cementum areas were observed on the mesial surface of the distobuccal and distopalatal roots. The mean root resorption area ratio of CG was significantly greater than EG (P<0.05). Results of the present study indicate that LiCl can attenuate orthodontically induce root resorption during orthodontic tooth movement. The effect of LiCl on tooth movement is insignificant.