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为解决现有检测方法存在前处理净化不完全、不彻底的情况，建立了超高效液相色谱（UPLC）测定食用油中香兰素、甲基香兰素和乙基香兰素含量的分析方法。用乙腈提取食用油中目标物，以乙腈饱和的正己烷萃取净化，冷冻分层后，再经Oasis PRiME HLB固相萃取柱净化，采用C18色谱柱分离，以0.5%甲酸水溶液-乙腈为流动相进行UPLC测定，外标法定量。结果表明：3种香兰素类物质在0.1~100.0 mg/L范围内线性关系良好，相关系数大于0.999，检出限均为0.03 mg/kg，定量限均为0.1 mg/kg；在 0.1、0.2、1.0 mg/kg 3个添加水平的平均回收率为86.6%~108.1%，相对标准偏差（RSD）为2.0%～8.8%。同时，采用本方法与BJS 201705中方法对食用油中的3种香兰素类物质进行测定，两种方法结果间无显著性差异。综上，建立的方法采用两步净化，减少了杂质对香兰素类物质的干扰，适用于食用油中香兰素类物质含量的测定。In order to solve the problem of incomplete purification in the pretreatment of the existing testing methods,a method for the determination of vanillin, methyl vanillin, and ethyl vanillin in edible oil by ultra high performance liquid chromatography (UPLC) was established. The target compounds in edible oil sample were extracted with acetonitrile, purified by n-hexane saturated by acetonitrile, frozen and stratified, then extracted and purified by Oasis PRiME HLB column, separated by C18 chromatographic column, and eluted with 0.5% formic acid aqueous solution and acetonitrile as the mobile phase gradient for the UPLC analysis. The external standard method was used for quantification. The results showed that the linearity of the three vanillins was good in the range of 0.1-100.0 mg/L, with correlation coefficient higher than 0.999, the detection limit was 0.03 mg/kg, and the quantitation limit was 0.1 mg/kg.The average recoveries at three additive concentrations of 0.1, 0.2 mg/kg and 1.0 mg/kgwere 86.6%- 108.1%, and the RSD was 2.0%-8.8%. There was no significant difference between the results of the established method and BJS 201705.The established method uses a two-step purification to reduce the interference of impurities to vanillin compounds, and is suitable for the determination of vanillins in edible oil.

Objective To explore the surgical design and surgical Methods for the minimally invasive extraction of embedded supernumerary teeth and to provide a reference for clinical practice. Methods A total of 87 embedded supernumerary teeth were removed from 85 patients. CBCT examination was performed before the operation. The nearest surgical approach was selected based on the distance between the embedded supernumerary teeth and the bony plate of the buccal tongue (lip and palate). The CBCT measuring ruler measured the maximum diameter of the impacted dental crown. According to the radius of the buccal and tongue directions of the crown, the upper and lower boundaries (bucco-lingual direction) of the bone to be deboned were determined with reference to the top of the alveolar crest or adjacent enamel cementum. A horizontal vertical line was made from the point to the meridian, and the length of the horizontal line was 1/2 the diameter of the impacted multiple crown. Thus, the radius determined the horizontal starting and ending points of the bone to be boneless. A trapezoidal or arcuate incision was made with an electric knife under block anesthesia and local infiltration anesthesia. The incision retained the gingival papilla. The upper and lower as well as the near and far midpoints of the bone were marked with a bone ruler. Starting from the midpoint area, the upper and lower points were connected. The mesial bone was removed in the mesial direction, and the range of the removed bone was slightly larger than the radius of the crown, showing the crown of the embedded supernumerary teeth. A surgical impact air handpiece with a 45-degree elevation angle or a piezosurgery device was used to divide the crown of the embedded supernumerary teeth into two parts. The crown and dental tissues were removed in pieces, the surgical area was cleaned and rinsed, and the wound was closed. Anti-inflammatory and swelling treatments were administered after the operation, and painkillers were prepared. The patients were revisited 7 days after the operation to check for wound healing. We asked and recorded the amount of painkillers taken by the patients. Results All patients had good wound healing 7 days after the operation, and the wounds were sutured. There was no swelling on the maxillofacial surface, and the degree of opening was basically normal. No other complications such as infection or numbness occurred. Fifty-eight patients did not take painkillers. Conclusion CBCT can be used to locate the embedded supernumerary teeth in bone. The surgical approach can be chosen based on the principle of proximity. During the surgery, the bone ruler is used to accurately locate the bone and remove the embedded supernumerary teeth in pieces, which can achieve a minimally invasive effect.

Compelling evidence indicates that dyslipidemia is positively associated with oral lichen planus (OLP). The types and magnitude of lipid metabolism disturbance in peripheral blood of OLP patients have been investigated in different studies. Yet, consensus on how these different lipid components varied in levels for the development of OLP lesions has not been reached so far. Herein, a total of 8 eligible studies were recognized, which enrolled 533 cases of OLP and 499 healthy controls. The analysis showed that the average total triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels were considerably higher, and high-density lipoprotein cholesterol (HDL-C) levels were significantly lower in OLP patients compared to healthy controls. Collectively, the lipid profile panel maybe serve as the potential predictive indicator for screening OLP. [ABSTRACT FROM AUTHOR]

Objective To investigate the levels of the Twist and Vimentin proteins in oral squamous cell carcinoma (OSCC) and analyze the clinical significance of Twist and Vimentin. Methods Eighty⁃five samples of OSCC and fif⁃ teen samples of normal oral mucosa were collected. Immunohistochemistry (SP method) was used to detect the expres⁃ sion of proteins, including Twist and vimentin. The relationship among these proteins and clinical pathological parame⁃ ters was analyzed using SPSS statistical software. Results In the normal group, 13.3% (2/15) of samples were positive for the Twist protein; this value was significantly lower than that in OSCC group (80.0%, 66/85) (c2＝26.98, P < 0.001). The expression of Twist was associated with clinical stage (c2＝5.40, P＝0.02) and lymph node metastasis (c2＝8.35, P＝0.006), while no correlations were found between the expression of Twist and sex (c2＝0.23, P＝0.63), age (c2＝0.31, P＝0.58), location (c2＝1.46, P＝0.235) or degree of differentiation (c2＝1.52, P＝0.47). Additionally, 6.7% of samples (1/15) were positive for vimentin; this value was significantly lower than that in OSCC group (74.1%, 63/85) (c2＝20.71, P < 0.001). The expression of vimentin was associated with clinical stage (c2＝4.51, P＝0.034) and lymph node metastasis (c2＝6.75, P＝0.009), while no correlations were found between the expression of vimentin and sex (c2＝0.40, P＝0.53), age (c2＝0.17, P＝0.68), location (c2＝0.74， P＝0.39) or degree of differentiation (c2＝4.58, P＝ 0.10). Spearman correlation analyses showed that Twist protein expression was positively correlated with vimentin (r＝ 0.578, P＜0.05). Conclusion Our data demonstrate that in OSCC, Twist and vimentin levels were upregulated, and Twist protein expression was positively correlated with vimentin, which indicates that both Twist and vimentin may be involved in the occurrence of OSCC.

It is known to all that Wnt signaling pathway plays an important role in the early development of tooth. Our previous research found that Wnt signaling pathway played crucial roles in dental development, and mutations in antagonist of Wnt signaling pathway may lead to the formation of supernumerary teeth. However, the expression pattern of Wnt signaling molecules in early development of tooth, especially genes with stage specificity, remains unclear. Hence, we applied RNA-seq analysis to determine the expression levels of wnt signal molecules at five different stages of rat first molar tooth germ. In addition, after literature review we summarized the function of Wnt signaling molecules during tooth development and the relationship between Wnt signaling molecules variation and tooth agenesis. Our research may have implications for exploring the role of Wnt signaling molecules in different stages of tooth development. [ABSTRACT FROM AUTHOR]

In order to solve the problems of complicated structure, poor operation stability and low efficiency of the heddle-in mechanism in the drawing-in machine, an automatic heddle-in system with a simple structure was designed. The heddle-in system includes three parts; upper heddle, threading and hedging. Firstly, the basic structure of the automatic heddle-in system was introduced, and the heddle-in process was planned. Secondly, the electromagnet and the adjusting needle were mechanically analyzed and optimized. Experimental results show that the movement error of the heddle-in system is reduced, and the stability, running speed and efficiency are improved. The average threading speed of heddle can reach 160 pieces/min. Compared with manual heddle-in, the speed is increased by nearly 9 times. It meets the requirements of drawing-in machine for automatic heddle-in, which greatly improves the production efficiency of the enterprise. [ABSTRACT FROM AUTHOR]

β- N-Acetylglucosaminidases (GlcNAcases) hydrolyse N-acetylglucosamine-containing oligosaccharides and proteins. These enzymes produce N-acetylglucosamine (GlcNAc) and have a wide range of promising applications in the food, energy, and pharmaceutical industries, such as synergistic degradation of chitin with endo-chitinases and using GlcNAc to produce sialic acid, bioethanol, single-cell proteins, and pharmaceutical therapeutics. GlcNAcases also play an important role in the dynamic balance of cellular O-linked GlcNAc levels, catabolism of ganglioside storage in Tay-Sachs disease, and bacterial cell wall recycling and flagellar assembly. In view of these important biological functions and the wide range of industrial applications of GlcNAcases, this review aims to provide a better understanding of various advances for these enzymes. It focuses on enzymatic properties of GlcNAcases, including substrate specificity, catalytic activity, pH optimum, temperature optimum, thermostability, the effects of various metal ions and organic reagents, and transglycosylation. [ABSTRACT FROM AUTHOR]