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Thisreview introduced the food allergens and their sensitization mechanism, and summarized the research progress of peanut, soybean, milk, shrimp, egg and kiwifruit allergens in ultrasound treatment. Moreover, the research direction of ultrasound treatment in reducing food sensitization was also prospected.

Background and purpose: Long non-coding RNA (lncRNA) has been found to be dysregulated in breast cancer and is closely related to the malignant behavior of tumors. This study aimed to explore the effects of LINC02163 targeting miR-338-3p on the proliferation, invasion and migration of breast cancer cells. Methods: Breast cancer tissue samples and the adjacent tissue samples (2 cm to cancer tissue) were collected from 9 female breast cancer patients admitted to People’s Hospital of Zhengzhou from January 2020 to September 2021. Real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) was used to detect the expression of LINC02163 in tissue samples, human normal breast epithelial cell line (MCF-10A) and breast cancer cell lines (MCF-7, BT-20, MDA-MB-231, T47D). MDA-MB-231 was divided into control group, sh-NC group, sh-LINC02163 group, sh-LINC02163+inhibitor-NC group and sh-LINC02163+miR-338-3p inhibitor group. MTT method, transwell test and scratch test were used to detect the MDA-MB-231 cell viability, invasion and migration ability. Western blot was used to detect the protein expression of c-Myc, matrix metalloproteinase (MMP) 2, MMP9, E-cadherin and N-cadherin in MDA-MB-231 cells. Dual luciferase reporter gene was used to detect the targeting relationship between LINC02163 and miR-338-3p. In vivo tumor formation experiment was used to detect tumor volume and weight in nude mice. Immunohistochemical method was used to detect the Ki-67 proliferation index in tumor tissues of BALB/c nude mice. Results: Compared with adjacent tissues, the expression of LINC02163 in breast cancer tissues was significantly higher (P0.05), the cell survival rate, number of invasive cells, migration rate, expressions of c-Myc, MMP2, MMP9 and N-cadherin, tumor volume and weight, and Ki-67 proliferation index were significantly increased, while the expressions of miR-338-3p and E-cadherin were significantly reduced (P

ObjectiveA portable high-sensitivity X-ray fluorescence spectrometry method was established to directly and quickly determine the content of arsenic， cadmium and lead in wheat flour.MethodsPart of the sample was put into the sample cup， and then directly put the sample cup into the portable high-sensitivity X-ray fluorescence spectrometer for testing. The testing time， sample compactness， and testing thickness of the instrument were optimized and applied to the detection of different types of wheat flour.ResultsThe relative standard deviation （RSD， n=6） of the precision was between 0.6% and 4.8%， and the recovery rate was 78.3%-120.4%. The detection limits of lead， cadmium and arsenic were 0.06 mg/kg， 0.06 mg/kg， 0.05 mg/kg， the quantification limits were 0.19 mg/kg， 0.19 mg/kg and 0.17 mg/kg， respectively. The correlation coefficient of portable highly sensitive X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry was greater than 0.98.ConclusionThe method has relatively high precision， good detection limit and quantification limit， and can meet the requirements of simultaneous rapid detection of multiple heavy metal elements in wheat flour.

In order to ensure safe and reliable operation of high power mine equipment in fault condition, a fault tolerant operation method of double winding WFSMs system in high power mine equipment was proposed. First, double winding WFSMs mathematical model under two phase rotating coordinate system was set up, and air gap flux was selected as main magnetic field of vector control. Then, mixture gap flux observer of self-switching voltage and current model were built. On this basis, double WFSMs vector control system was designed based on primary and slave parallel drive mechanism, and changing relationship of the WFSMs system models in fault condition was pointed out, then active current correction mechanism was introduced to realize tolerant operation of double winding WFSMs. Finally, 2.5 MW mine hoist industrial field test results show that the proposed method can realize tolerant operation of the system in fault condition, and meanwhile guarantee dynamic and steady state performance of the WFSMs drive system.

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the quantitative detection of bovine lactoferrin in dairy products. The samples were treated by degreasing and tryptic hydrolysis. Proteins of bovine lactoferrin and peptides were identified using ultra performance liquid chromatography-quadrupole/electrostatic orbitrap-high resolution mass spectrometry (UPLC-Q/Exactive-HRMS) and analyzed by Protein Pilot software. Eight species-specific marker peptides of bovine lactoferrin were identified by comparison of the basic local alignment search tool (BLAST) with the Uniprot database. Three markers with high response strength and stability were chosen for further quantitative research by UPLC-triple quadrupole mass spectrometry (QqQ-MS). The method showed a good linear relationship within its own range. The limits of detection and limits of quantification were 0.023-0.041 and 0.077-0.137 mg/kg, respectively. The observed recoveries were in the range of 93.8%-103.9%. The intra-day and inter-day RSDs were lower than 8.8% and 9.5%, respectively. This method presents various advantages such as strong anti-interference, high sensitivity and reproducibility, and it is suitable for the quantitative analysis of bovine lactoferrin in dairy products.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of 50 non-food additives in health food. The samples were extracted with methanol and purified using the QuEChERS method. The separation was performed on an Agilent Phoroshell SB C 18 column (150 mm×3.0 mm, 2.7 μm) with a mobile phase of 0.1% (v/v) formic acid aqueous solution and acetonitrile. The determination was performed by MS/MS in positive or negative electrospray ionization and multiple reaction monitoring mode. The results demonstrated that all 50 compounds could be well separated with a good linear relationship ( r 2 >0.99). The limits of detection (LODs, S/N ≥ 3) and limits of quantification (LOQs, S/N ≥ 10) were in the range of 0.010-1 mg/kg and 0.020-2 mg/kg, respectively. The matrix effects in five kinds of typical health foods (oral liquid, tablets, ointments, pills, and capsules) were evaluated and reduced by means of matrix matching. At the spiked levels of 1 LOQ, 2 LOQ, and 10 LOQ, the recoveries of all drugs varied from 63.1% to 115.7% with relative standard deviations (RSDs) of no more than 8.9% ( n =6). The method is simple, sensitive, practical, and suitable for monitoring 50 non-edible additives in health food.

A liquid chromatography-tandem mass spectrometry method for the identification of marker peptides of aquatic product allergens and quantitative detection of multiple allergens in meat products and seasonings was developed. The samples were prepared by protein extraction, protein purification, and trypsin hydrolysis. The proteins and peptides were identified using ProteinPilot by the data analysis of the ion spectrum of polypeptide fragments using ultra-performance liquid chromatography-quadrupole/electrostatic orbitrap high-resolution mass spectrometry (UPLC-Q/Exactive-HRMS). The identification of 30 species-specific marker peptides in Penaeus vannamei, Eriocheir, Scylla serrata, Thunnus thynnus , and Atlantic salmon by comparison of the basic local alignment search tool (BLAST) with the UniProt database was achieved. The verification and multiple reaction monitoring (MRM) quantitative studies of these marker peptides were performed using a triple quadrupole mass spectrometry (UPLC-QqQ-MS) system. The proposed method showed a good linear relationship in the range of 5-250 mg/kg. The limits of quantitation and observed recoveries were in the range of 2-3.5 mg/kg and 88.7%-110.2%, respectively. This method presents various advantages such as good repeatability and high throughput, suitability for rapid screening, and quantitative analysis of seven aquatic allergens in meat products and seasonings.

This study is to investigate the effect of the major chemical composition in rhizome of Pterocypsela elata, lactuside B, on expression of bcl-2, bax mRNA and their protein in rats' cerebral cortex after cerebral ischemia-reperfusion injury. First, middle cerebral artery ischemia-reperfusion injury model was established, and each group was treated with the corresponding medicines. Animals were separately sacrificed at 24 h and 72 h. The brain infarct volumes were detected by TTC dye, bcl-2 and bax mRNA expression was checked by RT-PCR, and the proteins of bcl-2 and bax were explored by two-step immunohistochemistry in cerebral cortex of rats. Lactuside B can reduce brain infarct volume of cerebral cortex of rats, increase the expression of bcl-2 mRNA and decrease that of bax mRNA. Moreover, the ratio of bcl-2 to bax mRNA is higher in 12.5 and 25 mg kg(-1) dose group, respectively, which is significantly different from that of model group (P < 0.05 or P < 0.01). Generally, either 12.5 or 25 mg kg(-1) dose group is better than positive control medicine nimodipine (P < 0.05 or P < 0.01). In addition, the expression of bcl-2 and bax protein is consistent with their gene expression. Infarct volume and the ratio of bcl-2 to bax mRNA expression are significantly different (P < 0.05 or P < 0.01) between 72 h and 24 h group. The results demonstrated that lactuside B could play a good role in resisting cerebral ischemia by upregulating the expression of bcl-2 mRNA and protein and downregulating that of bax mRNA and protein.