BACKGROUND: Mechanical stimulation plays a necessary regulatory role in developing and repairing many organs and tissues in the human body. Except for biochemical factors, mechanical factors are considered as key regulatory factors that affect the behavior and function of dental pulp stem cells. OBJECTIVE: To review the role and effect of cellular mechanical stimulation on the biological behavior of dental pulp stem cells. METHODS: PubMed, Embase, Medline and CNKI databases were searched for relevant literatures using the keywords of “human dental pulp stem cells (hDPSCs), mechanical strain, mechanical stretch, mechanical tension, shear stress, cell proliferation, osteogenesis differentiation” in English and Chinese, respectively. Fifty-six articles were finally eligible for review, which were closely related to the proliferation and differentiation of dental pulp stem cells under cellular mechanical stimulation. RESULTS AND CONCLUSION: Cellular mechanical stimulation is an important biological factor affecting cell proliferation, differentiation, apoptosis and protein expression. Dental pulp stem cells are mesenchymal stem cells derived from the dental pulp tissue, and their biological behaviors are also affected by cellular mechanical stimulation. Cellular mechanical stimulation is involved in the proliferation, odontogenesis/osteogenesis of dental pulp stem cells. When the dentin is subjected to fluid flow forces, mechanoreceptors are activated to regulate and maintain the integrity of tooth structure. Signal pathways that mediate the biological behavior of dental pulp stem cells include MAPK, Wnt, Akt, BMP-7, and Nrf2/HO-1, which are involved in promoting and inhibiting the proliferation and odontogenesis/osteogenesis of dental pulp stem cells to varying degrees.

【Objective】 To conduct a retrospective analysis of HIV Ag-Ab detection by ELISA in our blood center, so as to provide reference for continuous improvement. 【Methods】 The reactive rate of HIV by each reagent, reactive rate of both reagents, re-test rate, concordance rate of initial-repeat test, and reagent utilization rate were counted, and the external quality assessment results were analyzed by PT score and z-ratio. 【Results】 The total reactive rate of HIV was 0.15%. The reactive rate by both reagents was 0.02%. The re-test rates, reactive rates, concordance rates and reagent utilization rates of the two reagents were 0.09% vs 0.08%, 0.07% vs 0.06%, 75.86% vs 78.21%, and 114.54% vs 113.92%, respectively. PT score was 100%, and z-ratio of 7 negative samples and 1 positive sample was less than 2, and of 2 positive samples was more than 3. 【Conclusion】 The laboratory quality monitoring indicators and external quality assessment can effectively monitor the operation of blood testing laboratory.

The mixed teaching model combines the advantages of traditional teaching and network teaching in the “Internet +” era, which has become one of the important trends in the higher education teaching development. In order to follow this development trend, the human parasitology teaching team makes a reasonable use of modern information techniques, actively promotes the construction and application of online resources, and conducts mixed online and offline teaching based on MOOC resources and the experimental teaching digital platform. This mixed teaching model has shown a positive impact on both teaching and learning among teachers and students; however, students’ personalized independent and deep learning remains unsatisfactory. It is suggested that the online course resources construction, teaching design and digital literacy remain to be increased, so as to create a high-level, innovative and challenging online-offline mixed “golden course”

Objective The main intracellular signal of P2X₇ receptor activation is the increasing of Ca²⁺, which then presents the diversity of its physiological and pathological functions through multiple intracellular signal transduction. To observe the effect of activation of P2X₇ receptor on intracellular calcium（Ca²⁺）level in lateral midbrain periaqueductal gray (lPAG) neurons of primary cultured rat. Methods The primary cultured lPAG neurons were randomly divided into 4 groups: control group(no drug added), only for control; BzATP group(100 μmol/L); A-740003+ BzATP group(incubate with 100 nmol/L A-740003 for 10 min, then add 10 μmol/L ofBzATP); BzATP control group(add in Ca²⁺-free solution for 20 min, then add BzATP). The incubation solution of control group, BzATP group and A-740003+ BzATP group are DMEM/F12 medium, and the BzATP control group is Ca²⁺-free. The laser scanning confocal microscopy (LSCM) was used to detect : the changes of cultured neuron Ca²⁺ levels by different concentrations of BzATP; the effects of A-740003 and Ca²⁺-free medium preincubation on BzATP-induced Ca²⁺ level alterations in cultured neurons. Results BzATP dose-dependently increased the Ca²⁺ levels in cultured lPAG neurons; A-740003 and Ca²⁺-free medium inhibited the BzATP-induced increasing of Ca²⁺ level in cultured lPAG neurons. LSCM showed: The intracellular calcium fluorescence insensity(2.48±1.05) in the BzATP group was significantly higher than that in the blank control group, BzATP control group and A-740003+ BzATP group[(1.12±0.03), (1.09±0.03), (1.14±0.08)](P<0.01). Conclusion The activation of P2X₇ receptor can increase the level of lPAG neurons Ca²⁺ , and is associated with the extracellular Ca²⁺ influx.

Smallanthus sonchifolius， a plant resource with both medicinal and edible values， has been taken as fruit for a long history. Studies have proved that phenolic acids， flavonoids， sesquiterpene lactones， and fructooligosaccharides are the major compounds in S. sonchifolius. The extract of S. sonchifolius demonstrates noticeable antioxidant， anti-inflammatory， antimicrobial， and anti-cancer effects， as well as the activities of lowering blood glucose level， regulating intestinal function and so on. The rhizomes and leaves of S. sonchifolius contain abundant phenolic acids， mainly caffeic acid and its derivatives， which endow S. sonchifolius with remarkable antioxidant effect. Moreover， these substances can reduce blood glucose by improving insulin sensitivity. Fructooligosaccharides are abundant in the tuber of this plant， which can improve intestinal function by regulating intestinal flora. The sesquiterpene lactones in glandular trichomes on the leaf surface can inhibit the proliferation of cancer cells， among which uvedafolin and enhydrofolin have particularly strong activities. Furthermore， the sesquiterpene lactones have obvious inhibitory effect on Gram-positive bacteria. In terms of structure， the number of epoxy groups is linked to the strength of anticancer and antimicrobial effects. In addition， S. sonchifolius contains other compounds such as volatile oils， fatty acids， sterols， diterpenes， p-hydroxyacetophenone derivatives， and octulosonic acid derivatives， thereby exhibiting the pharmacological effects of treating Alzheimer's disease， protecting kidney， and lowering blood lipids. However， the isolation and identification of the main compounds in S. sonchifolius need further exploration， and the mechanism of action remains to be studied. Here we summarized the principal chemical components and pharmacological activities of S. sonchifolius， aiming to give a clue for the comprehensive development and utilization of this plant.

Objective: To evaluate the effect of compound electrolyte injection on phosphatidylserine (PS) exposure in erythrocytes after blood salvage-retransfusion in dogs. Methods: Twenty healthy mongrel dogs, weighing 10-15 kg, aged 3-5 weeks, were divided into 2 groups (n=10 each) using a random number table method: normal saline group (group NS) and compound electrolyte injection group (group MEI). The process of intraoperative blood salvage-retransfusion was simulated in both groups: femoral vein was cannulated for blood withdrawal until the volume of blood lost was 400 ml, and the shed blood was salvaged by a blood recovery machine.The washing solution was normal saline in group NS and compound electrolyte injection in group MEI.The erythrocytes were retransfused after being labeled with fluorescein isothiocyanate.Blood samples were obtained before and after blood salvage for determination of erythrocyte ATP content by enzyme-linked immunosorbent assay.Blood samples were obtained at 24, 48 and 72 h after blood retransfusion, and the PS exposure rate of the salvaged erythrocytes was determined by flow cytometry.The spleen was taken at 72 h after retransfusion to detect the phagocytosis rate of salvaged erythrocytes by monocytes. Results: There was no significant difference in ATP content before and after blood salvage between the two groups (P>0.05). Compared with NS group, the PS exposure rate of the salvaged erythrocytes at each time point after retransfusion and phagocytosis rate of salvaged erythrocytes by monocytes were significantly decreased in MEI group (P<0.05). Conclusion Compound electrolyte injection as a washing solution for intraoperative blood salvage can reduce the PS exposure in salvaged erythrocytes and is helpful in prolonging the lifespan of erythrocytes after retransfusion in dogs.

OBJECTIVES: Long non-coding RNA (lncRNA) has become a key epigenetic regulator that regulates gene expression and affects a variety of biological processes. LncRNA plays an important role in the occurrence and development of rheumatoid arthritis (RA). The study on lncRNA in peripheral blood cells of RA patients has been reported. However, there is no study on autophagy regulation by lncRNA in RA patients. This study aims to provide a new direction for the diagnosis and treatment of RA via screening the changes of lncRNAs in RA fibroblast-like synoviocytes (RA-FLSs) before and after autophagy and finding the key lncRNAs targeting RA-FLSs autophagy. METHODS: Synovial tissues of 6 RA patients after knee and hip joint surgery were obtained, and RA-FLSs were cultured to the 5th generation for further experiments (tissue culture method). After treatment with mTOR inhibitor PP242, the expression of LC3-II was detected by Western blotting. Total RNAs of 3 cases of RA-FLSs before and after treatment with mTOR inhibitor PP242 were extracted by TRIzol and screened by Agilent Human ceRNA Microarray 2019 (4×180 K, design ID: 086188) chip. The lncRNAs with significantly changed expression levels were selected (difference multiple≥2.0, RESULTS: RA-FLSs were successfully isolated and cultured from the synovial tissues of the patient's knee or hip joint. After 6 RA-FLSs were treated with PP242, the expression level of autophagy marker protein LC3-II was increased ( CONCLUSIONS Differentially expressed lncRNAs in RA-FLSs have been identified with microarray analysis. In RA, differential expression of lncRNAs is involved in the autophagy of RA-FLSs. The underlying mechanisms based on bioinformatics analysis include regulating the secretion of cytokines, such as IL-6, TGF-β, TNF-α and IL-17, participating in the immune cell differentiation, such as Th17, Th1, Th2 cells and osteoclasts, as well as regulating the autophagy pathway, MAPK, FoxO, and other signaling pathways. It has been verified that the expression of ENST0000584721.1 is up-regulated and ENST0000615939.1 is down-regulated after autophagy of RA FLSs, which provides a good experimental basis for further study on the mechanism of lncRNA in RA-FLSs autophagy.
Arthritis, Rheumatoid/genetics* ; Autophagy/genetics* ; Cell Proliferation ; Cells, Cultured ; Fibroblasts ; Humans ; RNA, Long Noncoding/genetics* ; Reproducibility of Results ; Synoviocytes

Acute myeloid leukemia (AML) is a malignant clonal disease of hematopoietic stem cells, characterized by the proliferation of abnormal primordial cells of myeloid origin in bone marrow, blood and other tissues. At present, the standard induction therapy for AML mainly includes “3+7” standard treatment(anthracycline combined with cytarabine), allogeneic hematopoietic stem cell transplantation (Allo-HSCT) and targeted drug therapy. However, AML cells usually express high levels of P-glycoprotein, which mediates the efflux of chemotherapeutic drugs, which makes AML cells resistant to chemotherapy, resulting in many patients who are not sensitive to chemotherapy or relapse after complete remission. And some patients can not tolerate intensive therapy or lack of donors and can not use Allo-HSCT therapy. Therefore, it is of great clinical significance to find new drugs to improve the efficacy of AML patients. Epigenetic disorders play a key role in the pathogenesis of many diseases, especially cancer. Studies have shown that most AML patients have epigenetic regulatory gene mutations, such as DNMT3A, IDH and TET2, and these mutations are potentially reversible, which has become one of the therapeutic targets of AML. Histone deacetylase inhibitors (HDACi) can regulate the balance between histone acetylation and deacetylation, change the expression of proto-oncogenes or tumor suppressor genes that control cancer progression from epigenetics, and play an important role in many kinds of tumor therapy. At present, HDACi has shown the ability to induce differentiation, cell cycle arrest and apoptosis of AML cells. The mechanism may be mainly related to HDACi inducing chromatin conformation opening of tumor suppressor gene by inhibiting HDAC activity, promoting oncogene damage and preventing oncogene fusion protein from recruiting HDAC. Although the preclinical outcome of HDACi is promising, it is not as effective as the conventional therapy of AML. However, the combination strategy with various anticancer drugs is in clinical trials, showing significant anti-AML activity, improving efficacy through key targeting pathways in a typical synergistic or additive way, increasing AML sensitivity to chemotherapy, reducing tumor growth and metastasis potential, inhibiting cell mitotic activity, inducing cell apoptosis, regulating bone marrow microenvironment, which provides a good choice for the treatment of AML. Especially for those AML patients who are not suitable for intensive therapy and drug resistance to chemotherapy. This review introduces the relationship between HDAC and cancer; the classification of HDAC and its function in AML; the correlation between HDAC and AML; the clinical application of five types of HDACi; preclinical research results and clinical application progress of six kinds of HDACi in AML, such as Vrinota, Belinostat, Panobinostat, Valproic acid, Entinostat, and Chidamide, the mechanism of HDACi combined with other anticancer drugs in AML indicates that the current HDACi is mainly aimed at various subtypes of pan-HDAC inhibitors, with obvious side effects, such as fatigue, thrombocytopenia, nausea, vomiting, diarrhea. In recent years, the next generation of HDACi is mainly focused on the selectivity of analogues or isomers. Finding the best combination of HDACi and other drugs and the best timing of administration to balance the efficacy and adverse reactions is a major challenge in the treatment of AML, and the continued development of selective HDACi with less side effects and more accurate location is the key point for the development of this drug in the future. It is expected to provide reference for clinical treatment of AML.

OBJECTIVE： To optimize the ethanol extraction technology of total alkaloids from Shuanghu capsules. METHODS： Using dendrobine as control， the contents of total alkaloids from Dendrobium nobile and Dendrobium officinale in Shuanghu capsules were determined by acidic dyes colorimetry. Using comprehensive scores calculated by the yield of the extract and the contents of total alkaloids as evaluation indexes， the effects of soaking time， ethanol volume fraction， extraction time， solid-liquid ratio and extraction times were investigated with single factor tests. L9（34） orthogonal test was used to optimize ethanol volume fraction， extraction time， solid-liquid ratio and extraction times according to the results of single factor test. The optimized technology was validated. RESULTS： The linear range of dendrobine were 4.16-14.56 μg/mL （r＝0.999 2）. RSDs of repeatability and precision tests were all lower than 5％. Average recovery tests were 93.01％ （RSD＝1.97％， n＝6）. The optimal ethanol extraction technology included soaking for 12 h， ethanol volume fraction of 70％， solid-liquid ratio of 1 ∶ 12 （g/mL）， extracting for 28 min， extracting 3 times. Results of validation test showed that the average yield of extract was 12.80％ （RSD＝4.39％， n＝3）， and the content of alkaloids was 0.359 0 mg/g（RSD＝0.66％， n＝3）. CONCLUSIONS： Established acidic dyes colorimetry is simple， precise and accurate， which can be used for the content determination of total alkaloids. The optimized ethanol extraction technology is stable and feasible， and can be used for the extraction of total alkaloids from Shuanghu capsules.

OBJECTIVE： To optimize the water extraction technology of total polysaccharide of Shuanghu capsules. METHODS： The total alkaloid was firstly extracted from Dendrobium nobile and Dendrobium officinale mixture of Shuanghu capsules with ethanol， and then total polysaccharide was extracted with water. Using glucose as control， total polysaccharide was treated with phenol-sulfuric acid method and its content was determined at 488 nm. Using comprehensive score calculated with the yield of the extract and the content of total polysaccharide as index， the effects of material-liquid ratio， extraction temperature， extraction time and times on the extraction were investigated by single factor test. Then L9（34） orthogonal test was used to optimize solid-liquid ratio，extraction temperature，extraction time and extraction times according to the results of single factor test. The optimized technology was validated. RESULTS： The linear range of glucose were 0.041 4-0.207 0 mg/mL（r＝0.999 9）. RSDs of intra-day and inter-day ranged 3.61％-8.24％ （n＝3，n＝5）， and RSD of repeatability test was 1.49％ （n＝6）. Average recovery rate was 98.65％（RSD＝1.45％，n＝6）. The optimal water extraction technology included solid-liquid ratio of 1 ∶ 25（g/mL），extraction temperature of 100 ℃，extracting for 90 min， extracting once. Results of validation tests showed that average content of total polysaccharide was 379.292 8 mg/g （RSD＝1.93％，n＝3） and average yield of the extract was 22.75％（RSD＝2.41％，n＝3）. CONCLUSIONS： Established phenol-sulphuric acid method is simple， precise and accurate. The optimal water extraction technology is stable and feasible， which can be used for the extraction of total polysaccharides from Shuanghu capsules.