Objective:To construct a microfluidic organ-on-a-chip and evaluate its capability in simulating subchondral bone remodeling during the progression of osteoarthritis.Methods:The chip′s main body was designed based on the microfluidic technology and cell co-culture technique. MC3T3-E1 cells were cultured adherently within the cell seeding micro-chamber, with the culture medium perfused at a flow rate of 0.5 ml/min at the bottom of the micro-chamber. Evaluation metrics were as follows: (1) Assessment of the microfluidic organ-on-a-chip: The growth culture medium was perfused and simulation experiments were conducted to test the concentration differences and equilibrium times of the fluid inside and at the bottom of the cell seeding micro-chamber at various time points; live-dead staining was performed to observe the biocompatibility of cells cultured continuously for 3 days and 7 days at a set flow rate, which was divided into 3-day and 7-day groups. (2) Osteogenic potential of the microfluidic organ-on-a-chip: The osteogenic induction medium was perfused, and ALP staining and PCR were performed to compare the number of the black alkaline phosphatase (ALP)-positive cells and the expression levels of osteogenesis-related marker genes including osteoblast-specific transcription factor 2 (RUNX2), type I collagen (COL1A1), bone morphogenetic protein-2 (BMP-2), and osteocalcin (OCN) under static, 3-day and 7-day perfusion conditions, which was divided into static non-induced, static-induced and perfusion-induced groups. (3) Characterization of morphology and size, and biocompatibility of extracellular vesicles (EVs) of three osteoblast subtypes: Three different subtypes of osteoblasts were obtained [endothelial-type osteoblasts (EnOB)-EVs, stromal-type osteoblasts (StOB)-EVs and mineralizing-type osteoblasts (MinOB)-EVs]. Their morphology and size were obtained through transmission electron microscopy and particle size analysis. Growth medium containing EVs of three different cell subtypes was perfused, and cell proliferation/apoptosis assay was performed to compare the biocompatibility of the addition of different EVs concentrations (1, 1.25, 2.5, and 5 μg/ml) for 24 hours, which was categorized into the EnOB-EVs group, StOB-EVs group and MinOB-EVs group. (4) Osteogenic effect of EVs from three subtypes of osteoblasts: Osteogenic induction media containing EVs from three different osteoblast subtypes were perfused for 3 days, and ALP staining and PCR were performed to compare the number of black ALP-positive cells and the expression levels of osteogenesis-related marker genes including RUNX2, COL1A1, BMP-2, and OCN, which was divided into non-EVs group, EnOB-EVs group, StOB-EVs group and MinOB-EVs group.Results:(1) Evaluation of the microfluidic organ-on-a-chip: Simulation results showed that the concentration in the top layer of the upper chamber reached more than 95% of that in the lower chamber and that the concentration in the bottom layer was about 96.5% of that in the lower chamber after 12 hours of continuous perfusion, reaching an equilibrium state of the concentration difference between the upper and lower chambers. The results of live-dead staining showed that the chip was biocompatible at a flow rate of 0.5 ml/min, and the cell survival rate at 3 and 7 days of perfusion was (99.48±0.12)% and (97.07±1.05)% ( P<0.01). (2) ALP staining results showed that at 3 days, the perfusion-induced group showed the highest number of black ALP-positive cells, followed by the static-induced group, and the least in the static non-induced group. At 7 days, the static-induced group had the highest number of black ALP-positive cells, followed by the perfusion-induced group, and the least in the static non-induced group. PCR results indicated that at 3 days, the expression levels of RUNX2, COL1A1, BMP-2, and OCN were 1.00±0.03, 1.00±0.12, 1.00±0.01, and 1.00±0.02 respectively in the static non-induced group; 1.80±0.04, 4.05±0.37, 9.80±1.94, and 4.38±0.89 respectively in the static-induced group, and 2.45±0.23, 5.48±0.42, 91.50±4.56, and 10.82±4.96 respectively in the perfusion-induced group ( P<0.01). At 7 days, the expression levels of RUNX2 was 1.00±0.01 in the static non-induced group, 1.46±0.46 in the static-induced group, and 1.11±0.08 in the perfusion-induced group ( P>0.05); the expression levels of COL1A1, BMP-2, and OCN were 1.00±0.03, 1.00±0.13, and 1.00±0.09 respectively in the static non-induced group, 9.38±0.25, 14.27±4.35, and 84.01±4.02 respectviely in the static-induced group, and 2.39±0.08, 133.64±8.87, and 86.64±8.36 respectively in the perfusion-induced group ( P<0.01). When comparing the static non-induced, static-induced, and perfusion-induced groups at both 3 and 7 days, the perfusion-induced group demonstrated the strongest osteogenic capability. (3) Characterization of morphology and size and biocompatibility of EVs from three osteoblast subtypes: Under the transmission electron microscope, EVs from EnOB-EVs, StOB-EVs, and MinOB-EVs all exhibited a typical saucer-shaped morphology. The particle sizes of EnOB-EVs, StOB-EVs, and MinOB-EVs were (91.3±14.7)nm, (106.0±16.0)nm, and (68.1±10.7)nm, respectively. Cell proliferation/apoptosis assay results indicated that the optimal administration concentration of EnOB-EVs, StOB-EVs, and MinOB-EVs was all 1.25 μg/mL. (4) Validation of osteogenic effect of the microfluidic organ-on-a-chip on three types of EVs: ALP staining results showed that the non-EVs group had the fewest black ALP-positive cells, followed by the EnOB-EVs group, then the StOB-EVs group, and the MinOB-EVs group had the most. PCR results showed that the expression levels of RUNX2, COL1A1, BMP-2, and OCN were 1.00±0.01, 1.00±0.03, 1.00±0.02, and 1.00±0.02 respectively in the non-EVs group, 1.95±0.11, 6.78±2.04, 7.99±0.57, and 6.93±3.83 repectively in the EnOB-EVs group, 0.79±0.12, 5.68±1.53, 12.59±3.15, and 25.59±0.95 respectively in the StOB-EVs group, and 0.68±0.10, 4.36±0.69, 18.75±3.21, and 34.74±3.98 repectively in the MinOB-EVs group ( P<0.01). Compared with the non-EVs group, EnOB-EVs group, StOB-EVs group, and MinOB-EVs group, the MinOB-EVs group showed the most significant osteogenic effect. Conclusions:The microfluidic organ-on-a-chip constructed using microfluidic technology and cell co-culture techniques is capable of maintaining the normal growth of MC3T3-E1 cells, enhancing their proliferation and osteogenic induction differentiation. EVs released by osteoblasts at different stages possess osteogenic effects and can accelerate the bone sclerosis in the remodeling of subchondral bone during the progression of osteoarthritis.

Objective : To investigate the differences in gut microbiota and metabolites between urban and rural middle school students and explore their significance in gut homeostasis , so as to establish a healthy lifestyle and diet for children. Methods : Fecal samples were collected from middle school students in Hefei ( n = 14) and Jixi county ( n = 18 , Southern Anhui) , aged 13. 0 - 13. 5 years. Stool samples were sequenced by 16S ribosomal DNA (LC⁃MS) , followed by bioinformatic analysis. Results : Lachnoclostridium and Anaerostipes were dominant in the urban students that had been reported to be associated with colorectal cancer, atherosclerosis , depression and other disorders. In the village children , Ruminococcaceae UCG⁃002 , Barnesiella and Eubacterium dominated. An increased proportion of these microbes were related to metabolism of bile acids , short⁃chain fatty acids , lipid and carbohydrate decomposition , and play an important role in maintaining immune balance and physiological function. Additionally , significant differences in gut metabolites of the two groups were noted , mainly in arachidonic acid metabolism , platelet activation , serotonin metabolism , vitamin absorption , primary bile acid metabolism and other pathways. Conclusion Adolescent students of urban and mountainous areas differ in gut microbiota and metabo⁃ lites. Rural children have a healthy bacterial flora and metabolites in guts due to a reasonable lifestyle and diet in comparison with the city children.

Objective: To investigate the effects of hepatobiliary metabolie dysfunction on gut microbiota in rats with intrahepatic cholestasis of pregnancy (ICP). Methods: Forty Sprauge-Dawley(SD) rats at 10 days of gestation were randomly divided into two groups,25 for ICP induction and 15 as control. Estradiol benzoate, combined with progesterone, was given to the rats by intraperitoneal injjection from 10 to 14 days after gestation. Hepatic impairment indicators of total bilirubin(TBIL), alanine aminotransferase (ALT), aspartate aminotransferase (AST),-glutamyl transferase ( GGT), alkaline phosphatase(AL.P), and total bile acids (TBA) in sera of the animals were detected in each group to verify the model construction. Simultaneously, the liver tissues were subjected to pathology examination and fresh faeces samples were collected for 16S rDNA sequencing to explore the gut microbiota profiles. Results: The serum levels of TBIL,ALT,AST,GGT,ALP and TBA in ICP group were significantly elevated compared with the control (P<0. 05 );the ICP rats presented obvious characteristics of hepatobiliary disorders, showing prominent steatosis, necrosis of hepatocytes and infiltration of inflammatory cells, with formation of bile thrombus in some animals. The abundance of Eubacterium, Bacteroides, Parabacteroides distasonis and Bacteroides uniformis remarkably decreased wereas Prevotela and Fusobacterium significantly increased in ICP rats when compared with the control (P<0.05). Conclusion The hepatic injuries and bile acid metabolic disorders occurred in ICP rats,which resulted in dysbiosis of gut microbiota.

Objective : To investigate the effect of Rotundic acid (RA) on proliferation，migration and invasion a- bility of human lung adenocarcinoma cells as well as its possible mechanisms． Methods : Human lung adenocarci- noma A549 and PC9 cells were divided into control group，blank control group，solvent group and 20，40，60，80 μmol / L RA groups．CCK-8 assay and scratch assay were used to detect the proliferation and horizontal migration of human lung adenocarcinoma cells．Transwell migration assay and Transwell invasion assay were used to detect the longitudinal migration and invasion ability of A549 and PC9 cells in each group．The protein expression levels of ja- nus kinase 2 (JAK2) and signal transducer and activator of transcription 3 ( STAT3) in the supernatants of A549 and PC9 cells were detected by ELISA．The mRNA expression levels of JAK2 and STAT3 were detected by RT- PCR. Statistical analysis was made on the differences among groups in each index. Results : After RA treatment on human lung adenocarcinoma cells ，compared with the control group ，the proliferation activity of A549 and PC9 cells in the experimental groups decreased (P＜0. 05) ，the number of cells crossing polycarbonate membrane and matrix glue decreased (P＜0. 05) ，the expression of JAK2 and STAT3 proteins in cell supernatant decreased (P < 0. 05) ，and the mRNA expression of JAK2 and STAT3 decreased (P＜0. 05) ．The decrease of the above indices was concentration-dependent and had statistical significance (P＜0. 05) ．Compared with the control group，the pro- liferation activity of A549 and PC9 cells in the solvent group showed no significant difference． Conclusion RA may inhibit the proliferation，migration and invasion of human lung adenocarcinoma A549 and PC9 cells in vitro， possibly through the inhibition of JAK2 / STAT3 pathway.

Objective: To explore the high expression level of serum heat shock protein 90α(HSP90α) and gene HSP90 AA1 in cancer tissue, and to discover the prognosis of lung cancer. Methods: A total of 109 cases of lung cancer were collected as the experimental group; 38 lung inflammation groups as the reference group; and 30 healthy controls. The serum HSP90α levels between the three groups were compared; the correlation between HSP90α and clinical parameters were analyzed. The TCGA data were used to analyze the correlation between the expression level of HSP90 AA1 and various pathological features, as well as its influence on the prognosis of lung cancers. Results: The serum HSP90α concentrations in the experimental group were higher than those of the reference group and the control group(P<0.05). The ROC curve area of HSP90α in the diagnosis of lung cancer was 0.898(P<0.05); the expression of HSP90α in the lung squamous cell carcinoma group(LUSC) and the small cell lung cancer group(SCLC) were higher than those in lung adenocarcinoma group(LUAD)(P<0.05); the level of HSP90α decreased when condition alleviated, while increased significantly when disease progressed(P<0.05); Further TCGA database showed that the expression of HSP90 AA1 in cancer tissues was higher than that of adjacent cancer tissues(P<0.05),meanwhile, remarkably increased in LUSC compared with in LUAD(P<0.05). The expression of HSP90 AA1 has no significant correlation with the age, gender, clinical stage, and tumor residue of lung cancer patients. Survival analysis and Cox regression analysis showed that high expression of HSP90 AA1 reduced the overall survival(OS) of lung cancer patients; HSP90 AA1 was an independent prognostic factor for lung cancer patients. Conclusion Serum HSP90α and HSPAA1 in cancer tissues are elevated in patients with lung cancer, which should be used as an auxiliary diagnosis method for lung cancer. Meanwhile they should be used for therapeutic effect observation and survival status prediction.

Objective:To explore the effect of 1-methyltryptophan (1-MT) on lipopolysaccharide (LPS)-induced permeability and apoptosis of human umbilical vein endothelial cells (HUVECs).Methods:HUVECs were treated with phosphate buffer saline (PBS, control group), 1 μg/mL LPS (LPS group), and LPS combined with 1 mmol/L 1-MT (1-MT group). The expression levels of the p120 concatemer (p120ctn), vascular endothelial (VE) cadherin, caspase-3, and DNA repair enzyme polyadenylate ribose polymerase-1 (PARP) after incubation at 8 h were detected using Western blot. The concentrations of kynurenine (Kyn) after incubation at 2, 4, 6, and 8 h were measured by high-performance liquid chromatography, and indoleamine2, 3-dioxygenase (IDO) activity was calculated. Comparisons among groups were performed using the LSD- t test. Results:Compared with the control group, the expression of caspase-3 [(74.01±7.91)% vs (157.14±7.63)%, P<0.01] and the concentration of Kyn were significantly up-regulated, while the expression of p120ctn [(49.12±2.15)% vs (37.61±1.80)%, P<0.01], VE-cadherin [(107.70±7.01)% vs (90.66±2.58)%, P=0.027], and PARP-1 [(67.95± 3.08)% vs (57.93±5.26)%, P=0.038] were significantly down-regulated, and IDO activity was significantly increased in the LPS group ( P<0.05). Compared with the LPS group, the expression of caspase-3 [(157.14±7.63)% vs (110.74±7.89)%, P<0.01] was significantly down-regulated, while the expression of p120ctn [(37.61±1.80)% vs (47.19±0.82)%, P<0.01], VE-cadherin [(90.66±2.58)% vs (107.27±9.89)%, P=0.029], and PARP-1 [(57.93±5.26)% vs (74.12±4.90)%, P=0.005] were significantly up-regulated, and the activity of IDO was significantly decreased over time in the 1-MT group ( P<0.05). No significant differences were observed between the PBS and 1-MT groups in the protein levels of p120ctn, VE-cadherin, and PARP-1 protein as well as Kyn concentration and IDO activity ( P>0.05), while the expression of caspase-3 was increased in 1-MT group ( P=0.001). Conclusions:LPS aggravates the permeability of HUVECs, which can be reversed by 1-MT via inhibiting IDO activity and reducing Kyn concentrations. Moreover, 1-MT can also reduce apoptosis, which may be via increasing the expression of PARP-1 and reducing the expression of caspase-3, thus protecting endothelial cells.

Objective To investigate the application of the cross-sectional area ratio of internal jugular vein and common carotid artery (IJV/CCA) in the evaluating the volume responsiveness of critically ill patients. Methods The capacity of critically ill patients were prospectively assessed. The diameter and sectional area of the IJV and CCA were measured by bedside ultrasonography. The cross-sectional area ratio of IJV/CCA was calculated and compared with the variety of cardiac output (ΔCO) after passive leg raising (PLR). Then the correlation index between the cross-sectional area ratio of IJV/CCA and ΔCO was evaluated, and the sensitivity and specificity parameters of capacity status were assessed by the cross-sectional area ratio of IJV/CCA. Results Of 55 critically ill patients in this study, 34 cases had positive volume responsiveness, and 21 case negative volume responsiveness.The general clinical data of the two groups had no statistically significant difference. The cross-sectional area ratio of IJV/CCA in the positive group was significantly less than that of the negative group (1.38±0.55 vs. 2.16±0.68, P<0.01). There was a significant correlation between the IJV/CCA cross-sectional area ratio and the ΔCO value of PLR (r=-0.67, P<0.01). When the ratio of the cross-sectional area of IJV/CCA was 1.65, the sensitivity of the assessment capacity was 86.4％ and the specificity was 78.8％. Conclusions The use of portable bedside ultrasonography is a noninvasive, convenient and reliable method to evaluate the capacity state of the critically ill patients.

Objective To identify the expression of long non-coding RNAs(lncRNAs) and their putatively modulated cytokines in human immunodeficiency virus(HIV)-1 infected monocytes and to explore the role of lncRNAs in immunomodulation of HIV-affected host cells.Methods RNAs arrays were used to screen the lncRNAs differentially expressed in HIV-infected monocytes and subsequently confirmed by quantitative real time PCR (qRT-PCR).A siRNA was designed and transfected to the human monocytes, followed by interleukin(IL)-1β, IL-10 and tumor necrosis factor(TNF)-α detection with ELISA.Results The results of the screening assays and qRT-PCR showed that the expression of lncRNA-n266623 was up-regulated in monocytes after HIV-1 infection;the secretions of IL-1β,IL-10 and TNF-α in human monocytes were significantly enhanced following transfection of siRNA targeting lncRNA-n266623 in the monocytes.Conclusion The HIV-1 infection can promote the expression of lncRNA-n266623 which may inhibit the expressions of IL-1β, IL-10 and TNF-α in monocytes and negatively regulate the immune response to HIV-1 infection.

Aim To construct and express the eukary-otic expression vector of double-stranded RNA-depend-ent protein kinase (PKR)fusion green fluorescent and analyse its antiviral activity of HBV in vitro.Methods The PKR gene was cloned into an empty expression vector pEGFP-N1 using molecular clone technology. After being confirmed by restriction enzyme digestion and sequencing methods,the recombinant plasmid was named as pEGFP-PKR that was subsequently transfect-ed into HepG2.2.15 cells using LipofectamineTM2000. The expression level of PKR in HepG2.2.15 cells was confirmed by using fluorescent microscopy. Mean-while,HBV DNA and HBsAg/HBeAg were detected by real-time PCR and electrochemiluminescence meth-od,respectively.Results Both restriction enyme di-gestion and sequencing assays showed that the recombi-nant vector pEGFP-PKR was successfully constructed in our study.Fluorescent microscopy observation indi-cated that the fusion protein pEGFP-PKR expressed ef-ficiently in HepG2.2.15 cells.Moreover,compared with the empty vector group,the expression of HBV antigen in supernatants was significantly decreased (P<0.05 ).However,the extracellular HBV DNA ex-pression was not inhibited significantly.Conclusion In vitro,PKR proteion has certain antiviral activity of HBV.

Objective To clone express and purify Schistosoma japonicum fructose?1 6?bisphosphate aldolase SjFBPA in E. coli and observe its expression in different developmental stages of S. japonicum. Methods FBPA gene was amplified from S. japonicum adult worm cDNA by using PCR. The amplified product was recombined into pET28a plasmid and inducibly expressed with IPTG in E. coli BL21. SDS?PAGE and Western blotting were employed to analyze and identify the recombinant protein SjFBPA rSjFBPA . Then rSjFBPA was purified by chromatographic purification and its purity was analyzed by SDS?PAGE. The protein concentration of rSjFBPA purified was measured by the BCA method. Furthermore SjFBPA mRNA was ana?lyzed in different developmental stages of S. japonicum by RT?PCR. Results SjFBPA was successfully amplified by using PCR and identified by restriction enzyme digestion and sequencing. The Western blotting analysis confirmed that the recombinant pro?tein could specifically reactive to the anti?His?tag monoclonal antibody. The concentration of the purified recombinant protein was about 4 mg/ml. The result of RT?PCR showed that SjFBPA mRNA was expressed in cercaria schistosomulum adult worm and egg of S. japonicum. Conclusion SjFBPA is successfully recombined and expressed in a prokaryotic system and SjFBPA mRNA is expressed in cercaria schistosomulum adult worm and egg of S. japonicum.