An analytical method was developed for determination of P and Si in edible vegetable oil using inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS).The microwave-assisted acid digestion of vegetable oil using HNO3 + H2O2 was carried out in closed vessels.The mass spectral interferences were eliminated by O2 mass shift when promoting reaction with O2 inside the collision reaction cell (CRC), and the monitoring of P as 31P16O+ product ion significantly improved the accuracy of the analysis.H2 was added into the CRC for H2 on-mass reaction.The interferences were eliminated by the quadrupole analyzer to accurately identify 28Si+.The effects of the flow rate of O2 and H2 in ORS3 on the signal intensities and BECs of 31P16O+ and 28Si+ were investigated.The optimum O2 and H2 flow rate was determined.Under the optimized conditions, the limits of detection were 0.043 and 0.66 μg/L for 31P16O+ and 28Si+, respectively.The accuracy of the analytical method was assessed by the analysis of the standard reference materials lubricant oil (SRM 1848) from the National Institute of Standard and Technology.No significant differences were observed between the certified values and measured values.This method was used to analyze 5 kinds of edible vegetable oils (rapeseed oil, sunflower oil, peanut oil, corn oil and soybean oil) from different regions of China, and it was found that the content of P was the highest in peanut oil, and Si showed the highest content in soybean oil.

Objective To study the impact of psychological care and health education on patients with digestive tract cancer and abnormal emotion receiving chemotherapy. Methods A retrospective analysis was carried outin 245 patients with malignant digestive tract cancer from July 2005 to July 2009 treated in our hospital, 147 cases of these patients received psychological care and health education besides conventional therapy were set as the intervention group, 98 cases given only basic nursing care were set as the control group. The clinical efficacy was analyzed in the two groups before and after chemotherapy using anxiety and depression indexes as indicators. Results After chemotherapy, SAS and SDS scores were significantly lower, while the survival time was significantly higher in the intervention group than those of the control group. Conclusions Psychological care and health education can reduce abnormal emotion in patients with malignant digestive tract cancer receiving chemotherapy and prolonged their survival time.

Objective: To evaluate the post-marketing safety of inactivated Enterovirus type 71 (EV-A71) vaccine (human diploid cell) . Methods: A total of 20 191 healthy children aged 6 to 59 months were invited to receive 2 doses of EV-A71 vaccine in Zhejiang Province from September 2016 to December 2017. Child caregivers were followed up on the 4^th or 5^th day after each EV-A71 vaccination, and the incidence of local, systemic, and other adverse events within 3 days after vaccination was recorded to assess vaccine safety. Describe the differences in adverse events among children with different characteristics. Results: A total of 32 230 doses were observed in this study, of which 20 191 and 12 039 were vaccinated for the first and the second dose, respectively; and the incidence of adverse events within 3 days was 2.045% (413 doses) and 1.611% (194 doses), respectively. After the first and the second dose, the number of systemic adverse events was the highest, 371 and 175 cases, respectively, with an incidence of 1.837% and 1.454%, respectively; the number of local adverse events was the lowest, 14 and 2 doses, respectively, with an incidence of 0.069% and 0.017%. Local adverse events occurred after vaccination were generally mild, and only 2 patients had level of 3; among the systemic adverse events, 39 patients had a fever level of 3 or higher, accounting for 8.2% of the total fever. Most of the symptoms in the local adverse events did not require treatment, only 3 cases of vaccination site rash and 2 cases of pruritus were self-purchased drugs or outpatient treatment; except for 5 cases of fever, the other symptoms were not hospitalized in the case of systemic adverse events. Conclusion The incidence of adverse events within 3 days after vaccination with EV-A71 vaccine was low in children, mainly systemic adverse events, and the prognosis was good.

Due to good mechanical properties and biocompatibility, tissue engineering scaffolds have become the vital method for repairing and regenerating articular cartilage defects. With the continuous development of tissue engineering technology, many scaffolds preparation and formation methods have been developed and tested in the past decade, however, the preparation of ideal regenerative scaffolds remain controversial. As load-bearing tissue inside the body joints, the matrix structure and cell composition of articular cartilage are hierarchical, and there are several smooth natural gradients from the cartilage surface to the subchondral bone layer, including cell phenotype and number, specific growth factors, matrix composition, fiber arrangement, mechanical properties, nutrient and oxygen consumption. Therefore, in the design of regenerative scaffolds, it is necessary to achieve these gradients to regenerate articular cartilage in situ. In recent studies, many new biomimetic gradient scaffolds have been used to simulate the natural gradient of articular cartilage. These scaffolds show different mechanical, physicochemical or biological gradients in the structure, and have achieved good repair effects. The related articles on tissue engineering for the treatment of articular cartilage defects were retrieved by searching databases with key wordsarticular cartilage injury, cartilage repair and gradient scaffolds. In this work,the structural, biochemical, biomechanical and nutrient metabolism gradients of natural articular cartilage were studied and summarized firstly. Then, the latest design and construction of articular cartilage gradient scaffolds were classified. Besides that, the material composition (such as hydrogels, nanomaterials, etc.) and the preparation process (such as electrospinning, 3D printing, etc.) of grandient scaffolds were further enhanced. Finally, the prospect and challenge of biomimetic gradient scaffolds in cartilage engineering are discussed, which provides a theoretical basis for the successful application of gradient scaffolds in clinical transformation.

The treatment of articular cartilage (AC) injury caused by various reasons is still a major clinical problem. The emergence of cartilage tissue engineering brings new hope for the treatment of AC injury. In general, AC tissue engineering can be divided into two categories, including cell-based tissue engineering and cell-free tissue engineering. Although cell-based tissue engineering can repair cartilage damage to a certain extent, existing therapeutic strategies still suffer from limited cell sources, high costs, risk of disease transmission, and complex procedures. However, the cell-free tissue engineering avoids these shortcomings and brings hope for in-situ AC regeneration. Non-cellular tissue engineering is mainly used to recruit endogenous stem cells/progenitor cells (SCPCs) to reach the site of cartilage injury, and provide a suitable regenerative microenvironment to promote cell proliferation and chondrogenic differentiation, then the maturation of new cartilage tissue was promoted. Therefore, it is also called as cell-homing in situ tissue engineering. Successful recruitment of endogenous SCPCs is the first step in in-situ cartilage tissue engineering. This review aims to introduce chemokine response of cartilage injury, systematically summarize traditional chemoattractant (chemokines and growth factors etc.) and emerging chemoattractant (functional peptides, exosomes and nucleic acid adapters etc.), evaluate the combination mode between chemoattractant and delivery devices, discuss the prospects and challenges of chemoattractant-mediated in situ tissue engineering and provide theoretical basis for the design of endogenous SCPCs homing-based in situ tissue engineering.

BACKGROUND:As tissue engineering brings new hope to the worldwide problem of articular cartilage repair,the construction of light-curing 3D printed hydrogel scaffolds with biomimetic composition is of great significance for cartilage tissue engineering. OBJECTIVE:To construct a biomimetic methacryloylated hyaluronic acid/acellular Wharton's jelly composite hydrogel scaffold by digital light processing 3D printing technology,and to evaluate its biocompatibility. METHODS:Wharton's jelly was isolated and extracted from human umbilical cord,then decellulated,freeze-dried,ground into powder,and dissolved in PBS to prepare 50 g/L acellular Wharton's jelly solution.Methylallylated hyaluronic acid was prepared,lyophilized and dissolved in PBS to prepare 50 g/L methylallylated hyaluronic acid solution.Acellular Wharton's jelly solution was mixed with methacrylyacylated hyaluronic acid solution at a volume ratio of 1:1,and was used as bio-ink after adding photoinitiator.Methylacrylylated hyaluronic acid hydrogel scaffolds(labeled as HAMA hydrogel scaffolds)and methylacrylylated hyaluronic acid/acellular Wharton's jelly gel scaffolds(labeled as HAMA/WJ hydrogel scaffolds)were prepared by digital light processing 3D printing technology,and the microstructure,swelling performance,biocompatibility,and cartilage differentiation performance of the scaffolds were characterized. RESULTS AND CONCLUSION:(1)Under scanning electron microscope,the two groups of scaffolds showed a three-dimensional network structure,and the fiber connection of HAMA/WJ hydrogel scaffold was more uniform.Both groups achieved swelling equilibrium within 10 hours,and the equilibrium swelling ratio of HAMA/WJ hydrogel scaffold was lower than that of HAMA hydrogel scaffold(P＜0.05).(2)CCK-8 assay showed that HAMA/WJ hydrogel scaffold could promote the proliferation of bone marrow mesenchymal stem cells compared with HAMA hydrogel scaffold.Dead/live staining showed that bone marrow mesenchymal stem cells grew well on the two groups of scaffolds,and the cells on the HAMA/WJ hydrogel scaffolds were evenly distributed and more cells were found.Phalloidine staining showed better adhesion and spread of bone marrow mesenchymal stem cells in HAMA/WJ hydrogel scaffold than in HAMA.(3)Bone marrow mesenchymal stem cells were inoculated into the two groups for chondrogenic induction culture.The results of qRT-PCR showed that the mRNA expressions of agglutinoglycan,SOX9 and type Ⅱ collagen in the HAMA/WJ hydrogel scaffold group were higher than those in the HAMA hydrogel scaffold group(P＜0.05,P＜0.01).(4)These findings indicate that the digital light processing 3D bioprinting HAMA/WJ hydrogel scaffold can promote the proliferation,adhesion,and chondrogenic differentiation of bone marrow mesenchymal stem cells.