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Fermented foods are rich in protein and free amino acids, which are decarboxylated by microbial amino acid decarboxylase to produce biogenic amines. Excessive ingestion of biogenic amines poses a threat to human health. Tyramine, a biogenic amine having high toxicity, is present in fermented foods in large quantities, so developing safe and effective methods to control tyramine is of practical significance for improving the safety of fermented foods. In this article, the physiological functions, harms and limit standard of tyramine in fermented foods are described with an emphasis on the formation mechanism and control methods of tyramine, so as to provide theoretical references for further improving the safety of fermented foods.

【Objective】In order to solve the problem that it is difficult to make the temperature sensor of the Photonic Crystal Fiber (PCF) with Surface Plasma Resonance (SPR), a D-structure PCF temperature sensor is proposed. The micro-structure and arrangement of the air hole are also designed. The method of coating the polishing surface of the optical fiber with gold layer is used to stimulate the SPR of the optical fiber.【Methods】Ethanol is used as a temperature-sensitive material, and the temperature-sensitive effect is used as the temperature sensing mechanism to achieve the effect of temperature sensing. The finite element analysis method is used to simulate the thickness of the gold layer and the size of the elliptical air hole of the fiber respectively. The coupling characteristics between the core mode and the surface plasma mode are analyzed under different conditions, and the structure of the sensor is optimized.【Results】The temperature characteristics of the sensor are simulated. In the range of -80~80 ℃, the sensitivity of the sensor is 3.4 nm /℃, and the linearity is better than 0.969 63.【Conclusion】The temperature sensor designed in this paper has a wide temperature detection range, satisfactory sensitivity, and linearity, which can be used for real-time temperature monitoring in industrial, agricultural, and medical fields.

Objective To verify the function of exosomes from 293T cells over-expressing membrane-localized IL-3 in vitro, so as to lay a foundation for in vivo function verification in animal models of Alzheimer′s disease. Methods Using the patented structure of the group, a recombinant IL-3 lentiviral vector was constructed and virus-infected 293T cells were packaged. Stable cell strain over-expressing IL-3 was screened. The membrane localization of IL-3 was verified by flow cytometry and immuno-fluorescence. Il-3-exosomes were purified by ultra filtration centrifugation, the exosmic morphology was observed by transmission electron microscope, the size distribution and concentration of exosomes were detected by nano-flow analysis, and the expression of IL-3 and exosome related marker proteins were detected by Western blot. The effect of BV-2 on the phagocytosis of Aβ amyloid was detected by immuno-fluorescence. Results Through vector construction, virus infection, screening and verification of puromycin, 293T cell strain with stable over-expression membrane-anchored IL-3 was obtained. The purified exosomes were collected and the structures of double-layer membrane vesicles with a diameter of 50-100 nm were observed under transmission electron microscope. Western blot results proved the presence of CD63, ALIX, TSG101 and other exosome marker proteins and these molecules were rich in IL-3 as compared with the control, that suggested the successful purification of IL-3-exosomes. The results of immuno-fluorescence assay showed that IL-3-exosomes promoted the phagocytosis of Aβ amyloid by BV-2 cells in vitro. Conclusions The gene modified 293T cell exosomes membrane-anchored expression of IL-3 can play a role of both IL-3 and exosomes in vitro, which promote the phagocytosis of microglia, there for provides a new idea for the clinical treatment of Alzheimer′s disease.

Objective To construct chimeric antigen receptors modified γδT cells targeting at BCMA (BCMA CAR-γδT) and to evaluate its efficacy of anti-multiple myeloma in vitro. Methods Lentiviral vectors containing BCMA single-chain variable fragment were constructed and transiently transfected into 293T cells. The expression of foreign genes was verified by fluorescence microscopy and Western blot; the lentivirus was packaged and the virus titer was determined by flow cytometry. Human peripheral blood αβT cells were infected and γδT cells were examined for its infection efficiency; LDH release method was used to detect the cytotoxic activity of BCMA CAR-γδT cells against human multiple myeloma cell lines in vitro, and the difference of cytotoxic activity between CAR-γδT cells and CAR-αβT cells was compared by Incucyte S3 Live-Cell Analysis Instrument. Results Twenty-four hours after BCMA-CAR lentiviral vector was transferred into 293T cells, the expression of exogenous ZsGreen was microscopied by fluorescence microscope; CD3ζ was detected by Western blot, which showed that BCMA-CAR could be successfully expressed. The lentivirus was packaged, collected and concentrated(virus titer of 2.23×108 Tu/mL). Infected αβT cells and γδT cells from human peripheral blood in MOI=5, and the results of flow cytometry showed that infection efficiency of αβT cells was 59.18%±2.56%, γδT cells was 48.15±9.86%. The cytotoxic activity of CAR-γδT cells against human myeloma cell lines MM1.S, H929 with high expression of BCMA and K562 cells with over-expression of BCMA was higher than that of empty vector control γδ T cells,which were significantly enhanced (P＜0.001), but there was no difference in cell lines negative for BCMA expression; Live-Cell Analysis Instrument results showed that the cytotoxic activity of BCMA CAR-γδT cells and BCMA CAR-αβT cells against H929 in vitro was significantly better than their vector control cells. There was no difference in the cytotoxic activities of BCMA CAR-γδT cells as compared with against BCMA negative cell lines, and so do BCMA CAR-T cells. Conclusions Cytotoxic activity of BCMA CAR-γδT targeting at BCMA in vitro was significantly enhanced ,which is expected to serve as a novel allogeneic γδT cell product for cell adoptive immunotherapy of multiple myeloma.

Objective To evaluate the efficacy of simultaneous or staged management of uterine fibroids by transcervical resection of septum （TCRS）， reproductive endocrinology and clinical prognosis. Methods Clinical data of 87 patients with uterine septum complicated with uterine fibroids were collected. All patients were divided into the simultaneous （n = 43） and staged groups （n = 44） according to different surgical methods. In the simultaneous group， hysteroscopic TCRS and transcervical resection of myoma （TCRM） were performed simultaneously， whereas staged hysteroscopic TCRS and TCRM were conducted in the staged group. Surgical conditions， postoperative myometrial healing， endometrial and subendometrial blood flow parameters （flow index （FI）， vascularization flow index （VFI） and vascularization index （VI））， endometrial thickness， reproductive endocrine indexes （luteinizing hormone （LH）， follicle stimulating hormone （FSH）， estradiol （E2））， reproductive outcomes and complications were compared between two groups. Results All patients in both groups completed the surgery successfully. The operation time， time to the first off-bed activity and the length of hospital stay in the simultaneous group were shorter than those in the staged group （all P < 0.05）. In the simultaneous group， the proportion of patients with myometrial healing at 1 month after surgery was higher than that in the staged group （P < 0.05）. The differences in subendometrial VFI， FI， VI， endometrial thickness and E2， LH and FSH levels before surgery， 1 month and 3 months after surgery were not statistically significant between two groups （all P > 0.05）. The percentage of patients who were pregnant at postoperative 6 months in the simultaneous group was higher than that in the staged group （P < 0.05）. The difference in the incidence of complication was not statistically significant between two groups （P > 0.05）. Conclusions Simultaneous management of uterine fibroids by TCRS does not affect endometrial hemodynamics， endometrial tolerance， ovarian reserve function and reproductive endocrine function. In addition， it can shorten the operation time， time to the first off-bed activity and length of hospital stay， which is conducive to postoperative pregnancy and has a certain degree of safety.

Background Steriod-induced osteonecrosis of femoral head (SIONFH) cystic degeneration have a "double-edged sword" effect. The method of activating blood and dredging collate is effective in the treatment of early SIONFH, but its regulatory effect on bone resorption/angiogenesis/osteogenic protein in cystic degeneration remains unclear. Objective To investigate the effect of activating blood and dredging collate method on serum bone resorption/angiogenesis/osteogenic protein in patients with cystic degeneration of SIONFH. Methods Sixty patients with SIONFH admitted to the Hip Joint Research Center of Guangzhou University of Traditional Chinese Medicine from January 2019 to January 2021 were included as the study subjects and divided into the control group and treatment group according to random number table method, with 30 cases in each group. Another 30 volunteers with normal physical examination in hospital at the same period and no history of hormone use were selected as the normal group. The treatment group was treated with Huoxuetongluo capsule (2 g/time, 3 times/day) and calcium carbonate (600 mg/time, 1 time/day), the control group was treated with the same amount of calcium carbonate, and the course of treatment of both groups was 12 months, simultaneously limiting weight-bearing on the affected limb. Fasting serum was collected, and the expression levels of nuclear factor κB receptor activating factor ligand (RANKL), platelet-derived growth factor-BB (PDGF-BB), vascular endothelial growth factor A (VEGFA), osteoprotegerin (OPG) and cadherin-associated protein (CTNNB1) in serum were detected by enzyme-linked immunosorbent assay. The patients were followed up twice at the 6th and 12th month after discharge, and the collapse of femoral head was defined as the end event. Hip pain visual analogue score (VAS), hip function (Harris) score and necrotic area score were used to evaluate the efficacy. Results Baseline RANKL, PDGF-BB, OPG and CTNNB1 levels were compared among the three groups, and the differences were statistically significant (P