2. Bionic mechanical design and 3D printing of novel porous Ti6Al4V implants for biomedical applications
Journal of Zhejiang University. Science. B 2019;20(8):647-659
In maxillofacial surgery, there is a significant need for the design and fabrication of porous scaffolds with customizable bionic structures and mechanical properties suitable for bone tissue engineering. In this paper, we characterize the porous Ti6Al4V implant, which is one of the most promising and attractive biomedical applications due to the similarity of its modulus to human bones. We describe the mechanical properties of this implant, which we suggest is capable of providing important biological functions for bone tissue regeneration. We characterize a novel bionic design and fabrication process for porous implants. A design concept of “reducing dimensions and designing layer by layer” was used to construct layered slice and rod-connected mesh structure (LSRCMS) implants. Porous LSRCMS implants with different parameters and porosities were fabricated by selective laser melting (SLM). Printed samples were evaluated by microstructure characterization, specific mechanical properties were analyzed by mechanical tests, and finite element analysis was used to digitally calculate the stress characteristics of the LSRCMS under loading forces. Our results show that the samples fabricated by SLM had good structure printing quality with reasonable pore sizes. The porosity, pore size, and strut thickness of manufactured samples ranged from (60.95± 0.27)% to (81.23±0.32)%, (480±28) to (685±31) µm, and (263±28) to (265±28) µm, respectively. The compression results show that the Young’s modulus and the yield strength ranged from (2.23±0.03) to (6.36±0.06) GPa and (21.36±0.42) to (122.85±3.85) MPa, respectively. We also show that the Young’s modulus and yield strength of the LSRCMS samples can be predicted by the Gibson-Ashby model. Further, we prove the structural stability of our novel design by finite element analysis. Our results illustrate that our novel SLM-fabricated porous Ti6Al4V scaffolds based on an LSRCMS are a promising material for bone implants, and are potentially applicable to the field of bone defect repair.
4.Killing effect of dendritic cell vaccine transfected by recombinant adeno-associated virus with hAFP gene fragment on hepatocellular carcinoma cells in vitro.
Jian-hai SUN ; Yan-ling MA ; Ming-e PENG ; Ai-gui BIE ; Li LI ; Li LIU
Chinese Journal of Oncology 2010;32(5):334-338
OBJECTIVEDendritic cell vaccines are one of the important active immunotherapies for neoplasms. The aim of this study was to observe the killing effect of specific cytotoxic T lymphocytes (CTL) on liver carcinoma HepG2 and SMMC-7721 cells in vitro. The CTL was induced by human peripheral blood mononuclear cells-originated dendritic cells (DC) transfected by recombinant adeno-associated virus (rAAV) with hAFP gene fragment (137-145).
METHODSImmature DCs were generated from peripheral blood mononuclear cells of healthy volunteers and then transfected by rAAV with AFP gene fragment. The CTL was thereafter induced. The activities of DC and CTL were measured and the killing effect of the CTL on HepG2 cells was detected using M1Tr assay.
RESULTSThe mature DC, transfected or not, highly expressed CD40, CD86 and IL-12. IFN-gamma was highly expressed in the CTL. The DC-induced CTL could effectively recognize and destroy the HepG2 and SMMC-7721 cells.
CONCLUSIONDC transfected by rAAV can stimulate the proliferation and differentiation of lymphocytes and also induce the proliferation of CTL, and their own phenotypes are not significantly altered. The DC vaccine can be effectively used as an adjuvant immunotherapy for patients with hepatocellular carcinoma.
B7-2 Antigen ; metabolism ; CD40 Antigens ; metabolism ; Cancer Vaccines ; immunology ; Carcinoma, Hepatocellular ; pathology ; Cell Differentiation ; Cell Line, Tumor ; Cell Proliferation ; Cytotoxicity, Immunologic ; Dendritic Cells ; cytology ; immunology ; metabolism ; Dependovirus ; genetics ; Hep G2 Cells ; Humans ; Interferon-gamma ; metabolism ; Interleukin-12 ; metabolism ; Liver Neoplasms ; pathology ; Peptide Fragments ; genetics ; T-Lymphocytes, Cytotoxic ; immunology ; metabolism ; pathology ; Transfection ; alpha-Fetoproteins ; genetics
6.Low expression of SLC22A1 is associated with a poor prognosis of hepatocellular carcinoma: analysis of 303 patients.
Shu-Tong WANG ; Shun-Li SHEN ; Yun-Peng HUA ; Bin CHEN ; Ming KUANG ; Shao-Qiang LI ; Qiang HE ; Bao-Gang PENG
Journal of Southern Medical University 2015;35(10):1417-1421
OBJECTIVETo evaluate the association between SLC22A1 expression and the outcomes of hepatocellular carcinoma (HCC) patients.
METHODSA tissue microarray of 303 HCC and matched adjacent noncancerous liver tissues (ANLTs) were constructed. The expression of SLC22A1 was tested by immunohistochemistry (IHC) and scored by two pathologists according to a 12-score scale (a score>6 was defined as high expression, and a score≤6 as low expression). The correlation of SLC22A1 expression with the clinicopathological features and the patients' outcome was analyzed.
RESULTSAll the ANLTs had a IHC score of 12, as compared to only 29 (9.6%) of the HCC tissues. The patients were divided into 2 groups based on the IHC scores: 59% (180/303) in low expression group and 41% (123/303) in high expression group. The disease-free survival (DFS) rates and overall survival (OS) rates were significantly lower in low SLC22A1 expression group than in the high expression group. The 1-, 3-, and 5-year DFS rates were 43%, 31% and 27% in the low expression group, and were 58%, 47% and 43% in the high expression group, respectively. The 1-, 3-, and 5-year OS rates were 66%, 38% and 32% in low expression group, and were 80%, 57% and 50% in the high expression group, respectively. A low expression of SLC22A1 was positively correlated with the tumor diameter, BCLC stage, tumor differentiation, and AFP levels (P<0.05), and was an independent predictor of poor overall survival (HR=1.454; 95% CI, 1.050-2.013).
CONCLUSIONSDown-regulation of SLC22A1 is a malignant feature and a potential prognostic marker of HCC.
Carcinoma, Hepatocellular ; diagnosis ; metabolism ; Disease-Free Survival ; Down-Regulation ; Humans ; Immunohistochemistry ; Liver Neoplasms ; diagnosis ; metabolism ; Organic Cation Transporter 1 ; metabolism ; Prognosis ; Survival Rate ; Tissue Array Analysis
7.Experimental study of the total flavonoid in Hypericum perforatum on depression.
Li XU ; Cui-E WEI ; Ming-Bo ZHAO ; Jian-Nong WANG ; Peng-Fei TU ; Jian-Xun LIU
China Journal of Chinese Materia Medica 2005;30(15):1184-1188
OBJECTIVETo investigate pharmacological effects of the total flavonoid in Hypericum perforatum on depression.
METHODExperimental depression was induced by subcutaneous injection of reserpine in mice. The concentration of monoamine transmitters including 5-HT and NE, the activity of monoamine oxidase (MAO) in brain and reserpine-induced symptoms of depression, such as ptosis, attenuation of autonomous activity, behavioral despair, acquired helplessness and sleep, were measured respectively to evaluate the effects of the total flavonoid in H. perforatum on the depression.
RESULTThe total flavonoid in H. perforatum significantly decreased the activity of MAO, inhibited the ptosis and the attenuation of autonomous behavior induced by reserpine respectively. The levels of 5-HT and NE were also attenuated by the total flavonoid in H. perforatum remarkably. In addition, the total flavonoid in H. perforatum was shown to inhibit behavioral despair and acquired helplessness and to prolong the sleep time in the mice. Following the treatment with the total flavonoid in H. perforatum, 5-THP, at the dosage without any side-effects, caused the tremble in the mice.
CONCLUSIONThe results indicate that total flavonoid in H. perforatum can significantly inhibit the depression.
Animals ; Antidepressive Agents ; pharmacology ; Brain ; metabolism ; Depression ; chemically induced ; enzymology ; physiopathology ; Female ; Flavonoids ; isolation & purification ; pharmacology ; Hypericum ; chemistry ; Male ; Mice ; Mice, Inbred ICR ; Monoamine Oxidase ; metabolism ; Motor Activity ; drug effects ; Norepinephrine ; metabolism ; Plants, Medicinal ; chemistry ; Reserpine ; Serotonin ; metabolism ; Sleep ; drug effects
8.Evaluation of transcutaneous electroacupoint stimulation with the train-of-four mode for preventing nausea and vomiting after laparoscopic cholecystectomy.
Yu-yong LIU ; Shan-e DUAN ; Ming-xue CAI ; Peng ZOU ; Yong LAI ; Ya-lan LI
Chinese journal of integrative medicine 2008;14(2):94-97
OBJECTIVETo evaluate the efficacy of transcutaneous electroacupoint stimulation with a train-of-four (TOF) mode for the prevention of postoperative nausea and vomiting (PONV) in the patients undergoing laparoscopic cholecystectomy.
METHODSNinety-six ASA Grade I - II patients scheduled for laparoscopic cholecystectomy were randomized into Neiguan (P6) electroacupoint stimulation group (treated group) and a placebo control group (placement of electrodes without electroacupoint stimulation). The anesthetic regimen was standardized by needling at Neiguan on the left side and connecting the TOF peripheral nerve stimulator. The incidence of nausea, vomiting, severity, antiemetic dosage and the degree of pain were assessed at 0, 60, 120 min, and 24 h after surgery.
RESULTSThe incidence of nausea and vomiting, the dose of antiemetics and the occurrence of severe nausea were all significantly lower in the treated group compared with the control group and the score for pain was obviously reduced in patients of the treated group at 24 h post-operation (P<0.05 or P<0.01).
CONCLUSIONTranscutaneous electroacupoint stimulation at P6 with the TOF mode could reduce the incidence and severity of nausea and vomiting with analgesic effects.
Acupuncture Points ; Adult ; Antiemetics ; therapeutic use ; China ; epidemiology ; Cholecystectomy, Laparoscopic ; adverse effects ; Female ; Humans ; Incidence ; Intraoperative Period ; Male ; Pain ; pathology ; Postoperative Nausea and Vomiting ; drug therapy ; epidemiology ; prevention & control ; Transcutaneous Electric Nerve Stimulation ; methods
9.Effects of insulin like growth factor-1 on cell viability and tissue factor in vascular endothelial cells.
Qi-Lin MA ; Tian-Lun YANG ; Ming SUN ; Yuan-Jian LI ; Can-E TANG ; Zhen-Yu PENG ; Shi-Lin HE ; Fang-Ping CHEN
Chinese Journal of Hematology 2007;28(9):605-608
OBJECTIVETo study the effects of insulin like growth factor-1 (IGF-1) on cell viability and tissue factor (TF) in angiotensin II (Ang II) induced vascular endothelial cells and to investigate its mechanisms.
METHODS10(-6) mol/L Ang II was added to human vascular endothelial cells (HUVECs) culture media alone or 30 min after pretreatment with IGF-1 (0.1 microg/ml , 0.5 microg/ml, 2.5 microg/ml). Cell viability and AngII type 1 receptor (AT1-R) mRNA were evaluated after 24 h incubation with AngII. At the optimum concentration of IGF-1 affecting cell viability, the time dependent manner for 12 - 48 h incubation with Ang II was evaluated. TF, NOS and NO were investigated after 24 h incubation with Ang II. In addition, NO synthase inhibitor Nomega-nitro-1-arginine methylester(L-NAME) was added 30 min before addition of IGF-1 and Ang II, and cell viability, TF, AT1-R mRNA, NOS and NO were evaluated after 24 h incubation.
RESULTS(1) Ang II induced a decrease in cell vitality, an upregulation of AT1-R mRNA, an increase in TF, and a decrease in the activity of NOS and content of NO. (2) Pretreatment with IGF-1 significantly inhibited the decreased cell viability and upregulation of AT1-R mRNA. IGF-1 at 0.5 microg/ml showed the most obvious effects. This effect of cell viability recovery was in a time dependent manner during 12 -48 h. (3) IGF-1 also inhibited the increased content of TF, the decreased activity of NOS and the decreased content of NO. (4) The beneficial effects of IGF-1 on cultured endothelial cells were completely abolished by L-NAME.
CONCLUSIONIGF-1 pretreatment could enhance the ang II injured cell viability and anti-thrombosis capacity, and the protective effects may be related to activation of NOS-NO signaling pathway which inhibited AT1-R.
Angiotensin II ; pharmacology ; Cell Survival ; drug effects ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; physiology ; Humans ; Insulin-Like Growth Factor I ; pharmacology ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Receptor, Angiotensin, Type 1 ; genetics ; metabolism ; Thromboplastin ; metabolism
10.Relationship between the inhibitory effect of fraxetin on breast cancer and estrogen signaling pathway.
Hong-Nan HUO ; Kun-Peng XIE ; Li-Meng WANG ; Ying JIANG ; Wei ZOU ; Ming-Jie XIE
Acta Physiologica Sinica 2013;65(3):323-328
Estrogen signaling pathways play an important role in the regulation of the physiological function of breast cancer cell proliferation and apoptosis. The article used MTT assay, flow cytometer analysis and Western blot to detect the inhibition of fraxetin on MCF-7 cell cycle distribution and apoptosis, ERα, cyclin D1 and Bcl-2 expression levels, MAPK and PI3K signaling pathway to investigate the mechanism of anti-breast cancer of fraxetin. The results showed fraxetin inhibited E2β-stimulated MCF-7 cell proliferation in a dose- and time-dependent manner, reversed E2β-induced anti-apoptosis and promoted G0/G1 phase arrest. After treatment with fraxetin, the expression of ERα in MCF-7 cell was decreased, and estrogen genomic signaling pathway was inhibited by down-regulating the expression of cyclin D1 and Bcl-2 proteins. After MCF-7 cells were treated with fraxetin, the expressions of MAPK/Erk1/2 protein were reduced, which affected estrogen non-genomic signaling pathway. The results suggest fraxetin plays a part in anti-breast cancer function through E2β-mediated genomic and non-genomic signaling pathways.
Apoptosis
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Breast Neoplasms
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metabolism
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Cell Proliferation
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Coumarins
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pharmacology
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Cyclin D1
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metabolism
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Estrogen Receptor alpha
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metabolism
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Estrogens
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pharmacology
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Humans
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MCF-7 Cells
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Proto-Oncogene Proteins c-bcl-2
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metabolism
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Signal Transduction