Objective To explore the proper dosage of establishment of stable hepatic oval cells (HOC) prolif-eration model by using 2-acetaminofluorene (2-AAF) combined with two-third partial hepatectomy (2/3 PH) surgery, and to explore isolated and cultured method of HOC in vitro. Methods The 174 Wistar rats were randomly divided into 4 experimental groups (each group enrolled 30 rats), saline group (n=30), and untreated group (n=24). Rats of 4 experi-mental groups were underwent gavage of 5, 10, 15, and 20 mg/(kg ? d) 2-AAF, corresponding to the groups from No.1 to No.4 group. Rats of saline group received saline gavage and rats of untreated group didn’t received any treatment. A standard 2/3 PH surgery was performed on the 5th day after gavage, then the same gavage method was still administrated as preoperation untill rats were sacrificed. The liver tissues of 6 selected rats were adopted and identified by HE staining and immunohistochemical staining on 4, 8, 12, and 16 days after PH for observation of the proliferation of HOC in every group, on 4 days, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were tested in addition. HOC were isolated and purified by collagenase perfusion method and percoll gradient centrifugation. Results The surv-ival rates of untreated group,saline group,No.1 group,No.2 group,No.3 group,and No.4 group were 100% (24/24),93% (28/30),93% (28/30),90% (27/30),90% (27/30),and 80% (24/30) respectively. Compared with the saline group and untreated group, the levels of serum ALT and AST increased significantly in No.2, No.3, and No.4 group on the 4th day after PH (P<0.05). The results of HE staining showed that No.2, No.3, and No.4 group were observed visibly different level of damage at liver tissue, and the proliferation level of HOC were most obviously in No.3 and No.4 group. The results of immunohistochemical staining revealed that proliferation cells were positively expressed oval cell marker-6 (OV-6). The number of OV-6 positive cells were increased significantly with the increase of dosage of 2-AAF between 4 days and 12 days after operation, and proliferation levels were related with dosages of 2-AAF (P<0.05). In all cultured cells, 80% of cells were OV-6 positive cells after isolation and culture by using collagenase perfusion method and percoll gradient centrifugation. Conclusions The methods of gavage of 2-AAF at 15 mg/(kg ? d) combined with 2/3 PH surgery can establish the HOC proliferation model on the 12th day, as well as the rats have lower mortality and better tolerance, especially. The collagenase perfusion method and percoll gradient centrifugation can be used to isolate HOC effectively.
【Abstract】 Objective To observe the effect of cytokines and combinations in the inducement of human umbil icalcord blood-derived CD34+ cells into hepatocyte-l ike cells. Methods The mononuclear cells (MNCs) were derived by density gradient centrifugation and the CD34+ cells were sperated from MNCs. The human umbil ical cord blood-derived CD34+ cells were cultivated through 49 different combinations of cytokines including leukemia inhibitor factor (LIF), oncostatin M, bFGF, aFGF, hepatocyte growth factor, EGF and stem cell factor for 28 days, and the concentrations of the cytokines were 10, 10, 10, 10, 20, 20 and 50 ng/mL, respectively. The mRNAs of cytokeratin 19 (CK-19), CK-18, glutamine synthetase (GS), human albumin (ALB) and α-fetoprotein (AFP) were detected every seven days. The ALB secretion abil ity, detoxification abil ity and hepatin synthesis abil ity of the induced cells were detected by immunofluorescence assay, indocyanine green (ICG) and periodic acid-schiff assay, respectively. The fresh umbil ical cord blood-derived CD34+ cells were detected at the same time as a control. Results The mRNAs of CK-19, CK-18 and GS could be transcribed in all the induced cells, but the transcription of the mRNAs of ALB and AFP which was the special mark of mature hepatocyte and l iver stem cell, respectively, was not found. All the mRNAs could not be found in freshly isolated umbil ical cord blood-derived CD34+ cells. All the cells induced in vitro could not release ALB, and not help the detoxification of ICG which was the fundamental function of mature l iver cells. These results were the same in the control group. The hepatin synthesis abil ity of all the induced cells increased by comparison to the fresh ones. Conclusion Though some mRNAs of proteins which are transcribed in hepatocytes can be found in the induced cells, umbil ical cord blood-derived CD34+ cells could not be transdifferentiated into hepatocyte-l ike cells through cytokines in vitro.
Objective To establish a rapid, simple, and economic method to prepare osteoporosis (OP) in vitro model. Methods Eighty pairs of fresh goat femur were collected from 18-month-old female goats and were randomly divided into 4 groups (20 pairs in each group). The femur was immersed decalcifying solution (18% EDTA) for 1-5 days (group B), 6-10 days (group C), and 11-15 days (group D), while group A had no treatment as control. Four pairs of femur were taken out every day. Quantitative computed tomography was used to scan the medial and lateral femoral condyles, and the bone mineral density (BMD) was calculated. Electronic universal testing machine was used to do three-point bending test and compress and tensile ultimate strenght test, and the mechanical parameters for femur were calculated. Results With demineralized time passing, BMD of the medial and lateral femoral condyles were downtrend in groups A, B, C, and D, showing significant differences among 4 groups (P lt; 0.05); BMD of the lateral femoral condyle was significantly higher than that of the medial femoral condyle in each group (P lt; 0.05). The three-point bending test showed that broken load, ultimate strength, and elastic modulus of groups A and B were significantly higher than those of groups C and D (P lt; 0.05); but no significant difference was found between groups A and B, and between groups C and D (P gt; 0.05). Compress and tensile ultimate strength test showed that the compress and tensile ultimate strengths were significantly higher in group A than in groups C and D (P lt; 0.05), and in group B than in group D (P lt; 0.05), but no significant difference was found between groups A and B, between groups B and C, and between groups C and D (P gt; 0.05). Conclusion The 18% EDTA immersing for 6-15 days is a fast, simple, economical method to prepare an OP in vitro model of goat femur.
Objective To observe the synergistic effect of metformin and anti-vascular endothelial growth factor (VEGF) in the treatment of diabetic retinopathy. Methods This study was composed of clinical data review and in vitro cell experiment. Ten patients (12 eyes) with diabetic macular edema treated with anti-VEGF drugs were included in the study. Patients were randomly divided into the VEGF group (anti-VEGF drug therapy) and the combined treatment group (anti-VEGF drug combined with metformin). The changes of visual acuity and central retinal thickness (CRT) were compared between the two groups. As far as the in vitro experiment was concerned, vascular endothelial cells were divided into the control group (normal cells), the VEGF group (50 ng/ml VEGF), the anti-VEGF group (50 ng/ml VEGF+2.5 μg/ml of conbercept), and the combined group (50 ng/ml VEGF +2.5 μg/ml of conbercept +2.0 mmol/L of metformin). And then MTT cell viability assay, scratch assay and real-time quantitative polymerase chain reaction assay were performed to analyze the cell viability, cell migration and mRNA level of VEGFR2, protein kinase C (PKC)-α and PKC-β successively. ResultsReview of clinical trial shows that the CRT recovery rates in the combined treatment group were much higher than that in the VEGF group at 3 month after the operation, while the difference was statistically significant (t=−2.462, P<0.05). In vitro cell experiment results showed that VEGF induction upregulated the viability and mobility of vascular endothelial cells obviously compared with control group, at the same time, the use of anti VEGF drugs can effectively reverse the trend, in contrast, combination of metformin and anti-VEGF showed a more superior effect to some extent (P<0.05). In the VEGF group, the mRNA expression of VEGFR2, PKC-αand PKC-β were significantly increased compared with the control group (P<0.01); while the mRNA expression of VEGFR2, PKC-αand PKC-β in the combination group decreased significantly compared with the VEGF group and the control group (P<0.05). However, in the anti-VEGF group, the mRNA expression of VEGFR2, PKC-αand PKC-β were decreased, but has failed to reach the level of statistical learn the difference. ConclusionsThe combination of metformin and anti-VEGF drugs can reduce the CRT of diabetic retinopathy patients and inhibit the proliferation and migration of retinal vascular endothelial cells which induced by VEGF. The synergistic mechanism may be related to the inhibitory effect of metformin on the expression of VEGFR and PKC.
ObjectiveTo interpret the mechanisms of vascular repair disorders in steroid-induced avascular necrosis of the femoral head (SANFH) via detection of the changes of proliferation, migration, and macrophage migration inhibitory factor (MIF)/vascular endothelial growth factor (VEGF) expressions of endothelial cells (ECs) under hypoxia/glucocorticoid. MethodsAccording to culture conditions, human umbilical vein ECs (HUVECs) at passage 3 were divided into group A (normal), group B (1.0×10-6 mol/L dexamethasone), group C (hypoxia), and group D (hypoxia+1.0×10-6 mol/L dexamethasone). The cell activity was detected by AlamarBlue; the number of viable cells was detected in live/dead cell staining; the cell morphology was observed after cytoskeleton staining; cell migration ability was compared by scratch test; and the levels of MIF and VEGF expressions were detected by ELISA. ResultsAt 24 hours after culture, the cell activity and the number of living cells in group C were significantly higher than those in the other 3 groups, showing significant difference between groups (P < 0.05), and group D had the worst cell activity and least living cells. Cytoskeleton staining showed that cells had normal morphology in groups A and B; cells had rich cytoskeleton and secretion granules in group C; cytoskeleton form disorder and nucleus pyknosis were observed in group D. Scratch test showed that the cell migration ability of group C was strongest while cell migration ability of group D was weakest. Accumulated concentration of MIF and VEGF in 4 groups significantly increased with time extending. Accumulated concentration of MIF in group C were significantly higher than that in other 3 groups at each time point (P < 0.05). Within 24 hours after intervention, stage concentration of MIF during 1-8 hours was significantly lower than that during 0-1 hour and 8-24 hours in every group (P < 0.05). Stage concentration of MIF in group C was significantly higher than other groups during 0-1 hour and 8-24 hours (P < 0.05). Within 2 hours after intervention, stage concentration of MIF in 4 groups during 0.5-1 hour was significantly higher than that during other stages (P < 0.05). Accumulated concentration of VEGF in group C was significantly higher than that in other groups at 8 and 24 hours (P < 0.05). The stage concentration of VEGF in groups C and D during 8-24 hours was significantly higher than that during 0-1 hour and 1-8 hours (P < 0.05). There was no significant difference in the stage concentration of VEGF within and among group A, B, C, and D at every stage within 2 hours after intervention (P > 0.05). ConclusionIn hypoxia environment, the proliferation and migration of ECs is enhanced, and the secretion of VEGF and MIF is increased. High concentration of dexamethasone will suppress the process above, which induces vascular repair disorders and aggravating SANFH.
Objective Titania and Ag containing nano-hydroxyapatite/polyamide 66 (TiO2-Ag-nHA/PA66) composite bone fill ing material has good biocompatibil ity and biological safety. To investigate the antibacterial effect and Ag+ release characteristics of TiO2-Ag-nHA/PA66 composite bone fill ing material containing different concentrations of Ag+ in vitro. Methods The n-HA/PA66 composite bone fill ing material A1 (material A1) was prepared by co-polymerization method, and TiO2-Ag-nHA/PA66 composite bone fill ing materials A2 and A3 (materials A2 and A3) were prepared by thesame way containing Ag+ of 0.22wt% and 0.64wt%, respectively, and the TiO2 content was 2.35wt%. The materials A2 and A3 were respectively immersed in 50 mL simulated body fluid (SBF), and Ag+ concentration was measured by atomic absorption spectrometry at 1, 3, 7, 14, 21, and 49 days. The inhibition ring test and colony count method were used to evaluate antibiotic effect against Staphylococcus aureus and Escherichia coli, the anti-adhesion capacity of Staphylococcus aureus and Escherichia coli was observed by scanning electron microscope (SEM). Results There was no significant difference in the Ag+ concentration between materials A2 and A3 at 1 day and 3 days (P gt; 0.05); and there were significant differences in the Ag+ concentration between materials A2 and A3 after 7 days (P lt; 0.05). The inhibition ring diameters of materials A2 and A3 to Staphylococcus aureus and Escherichia coli reached the maximum at 1 day, which were (13.40 ± 2.88), (9.40 ± 1.14) mm and (23.60 ± 1.14), (18.80 ± 0.84) mm, showing significant difference (P lt; 0.05) between materials A2 and A3 respectively; and then, the diameter of inhibition ring reduced with the time. The antibacterial effect of materials A2 and A3 against Staphylococcus aureus and Escherichia coli lasted 15, 33 days and 9, 24 days, respectively. No inhibition ring was observed around material A1 all the time. And the inhibitory rates of materials A2 and A3 were 89.74% ± 3.62%, 94.18% ± 2.05% and 78.65% ± 5.64%, 85.96% ± 2.50%; showing significant differences (P lt; 0.05) among materials A1, A2, and A3. SEM showed that bacterial adhesion of materials A2 and A3 was obviously fewer than that of material A1. Conclusion TiO2-Ag-nHA/PA66 composite bone fill ing material has antibacterial property against Staphylococcus aureus and Escherichia coli, and it has a good release effect in SBF.
Objective To observe the morphology and growing status of mesenchymal stem cells(MSCs) of human bone marrow in vitro, in order to confirm that MSCs of human bone marrow are ideal seed cells and provide basic theory for further MSCs research. Methods The methods of density gradient centrifugation with lymphocyte separation medium for human and adherent filtration were used to isolate and purify MSCs of human bone marrow. We observed the cellular growth status and morphology of the primary MSCs and the surface antigens of second passage MSCs were tested. Results The primary culture cells fused into monolayer after 14-16 d. The passage cells kept the same morphological characteristics of primary culture cells. Ultrastructure of the second passage MSCs showed that the shape of nuclei was irregular, there were multiple nucleoli in some of the nuclei, and morphological differentiation of intracytoplasm organelles was immature. The growth curve of the first, fifth and tenth passage cells showed a logarithmic growth at day 3, a peak growth at day 5, and no clones occurred after tenth passage. Cloning efficiency of first passage, fifth passage and tenth passage was respectively 25.83%±2.93%, 14.67%±1.63% and 4.67%±0.52%. Test of MSCs phenotypic characteristics showed a high homogeneity among the cells and surface antigen profiles were positive for CD29, CD44 and negative for CD34, CD45. Conclusion The methods of density gradient centrifugation with lymphocyte separation medium for human and adherent filtration are simple, economic and efficient to isolate and purify MSCs from human bone marrow. With a high proliferating ability in vitro, MSCs from human bone marrow are ideal seed cells for tissue engineers.
Objective To analyze the efficacy and safety of different acupuncture methods on outcome of in vitro fertilization-embryo transfer (IVF-ET). Methods The PubMed, EMbase, Cochrane Library, CNKI, VIP, WanFang Data and CBM databases were searched to collect randomized controlled trials (RCTs) related to the objectives of the study from the inception to April 16, 2023. After two investigators independently screened the literature, extracted the data and evaluated the risk of bias of the included studies, a network meta-analysis was performed using Stata 16.0 software. Results There were 62 trials total with 9844 patients, involving 7 interventions. Network meta-findings analysis revealed the following: ① Clinical pregnancy rate (CPR): needle warming > auricular acupressure > transcutaneous electrical acupoint stimulation (TEAS) > electroacupuncture > acupuncture > sham acupuncture > no adjunctive treatment; ② Live birth rate (LBR): electroacupuncture > auricular acupressure > TEAS > acupuncture > sham acupuncture > no adjunctive treatment. Conclusion Needle warming assisted IVF-ET is superior to other acupuncture therapies in improving CPR, especially during the promotion period of excretion, and the selection of Zusanli, Guanyuan and uterine acupoints for 3-month cycles may have the best effect. And for the LBR, the effect of electroacupuncture is better than that of other therapies. Besides, auricular acupressure may have good therapeutic potential. Due to the limited quality and quantity of the included studies, more high quality studies are required to verify the above conclusions.
Objective To systematically review the effectiveness of letrozole combined with GnRH antagonist for in vitro fertilization-embryo transfer (IVF-ET) in poor responders. Methods Such databases as VIP, CNKI, PubMed, EMbase and FMJS were electronically searched for randomized controlled trials (RCTs) or quasi-RCTs on the effectiveness of letrozole combined with GnRH antagonist for IVF-ET. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data, and assessed methodological quality. Then, meta-analysis was performed using RevMan 5.0 software. Results Six studies involving 977 patients were finally included. The results of meta-analysis showed that, for IVF-ET poor responders, compared with the control group, the letrozole combined with GnRH antagonist group had less dosage of Gn (MD=–8.05, 95%CI –13.67 to –2.43, P=0.005), and lower serum E2 value on the day of HCG administration (MD= –1 026.41, 95%CI –1 949.61 to –103.20, P=0.03). However, no significant difference was found in the number of ocytes obtained (MD= –0.61, 95%CI –2.41 to –1.19, P=0.51) and clinical pregnancy rates (OR=1.03, 95%CI 0.53 to 2.02, P=0.92) between the two groups. Conclusion As for the effectiveness of impelling-ovulation treatment for IVF-ET in poor responders, letrozole combined with GnRH antagonist is similar to the control scheme in clinical outcomes, but it reduces the dosage of Gn and treatment costs of IVF-ET, which provides another clinical option for poor responders. Due to the limited quantity and quality of the included studies as well as the difference in methodology, we suggest this above conclusion could be taken as a reference for clinical analysis which needs to be further evaluated in its effects.
ObjectiveTo evaluate the feasibility and security of endovascular repair of abdominal aorta using branched stent graft in a novel in vitro vascular model. MethodsThe branched stent graft for the abdominal aorta was designed. The novel in vitro vascular model was established to test this stent graft. Attempts were made to optimize the procedure of stent graft and to evaluate the feasibility of this device. The branched stent graft for abdominal aorta was tested by a novel in vitro vascular model. The number of stent graft released and expanded was recorded respectively. The pressure and situation of branch vessels were assessed before and after stent graft released. The endoleak during releasing process was observed by digital subtraction angiography (DSA). ResultsThe stent graft was successfully deployed in the novel in vitro vascular model. The releasing process was all properly achieved (100%, 30/30). The pressure changes of branch vessels were no statistical significances (P > 0.05) between before and after stent graft released. The stent grafts were well landed, and were fully expanded and properly positioned by DSA. No endoleak occurred. ConclusionThe branched stent graft for abdominal aorta in a novel in vitro vascular model is safe and feasible.