Bio-Medical Materials and Engineering - Volume 22, issue 1-3

Authors: Dong, Lanlan | Liu, Yongjuan | Qiu, Yanyan | Peng, Biwen | Yin, Jun | Liu, Wanhong | He, Xiaohua

Article Type: Research Article

Abstract: Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, especially in China. Recent researches have shown that E3 ubiquitin ligases Pirh2 (p53-induced RING-H2 protein) is highly expressed in HCC cell lines and is correlated with poor survival and prognostic in patients with HCC; however, the function of Pirh2 in the genesis and the development of HCC remains unclear. Pirh2, a member of the RING finger family, can target p53 for degradation and thereby repress a diverse group of biological activities and involved in many signalling pathways related to the genesis and evolution of cancer. Up to …now, four Pirh2 variants had been reported and named Pirh2A, Pirh2B, Pirh2C and Pirh2D. Here we report the existence of two additional isoforms from human hepatocellular liver carcinoma cell line (HepG2 cell) and named as Pirh2E and Pirh2F. Compared to full-length Pirh2A, Pirh2E lacks amino acids 235–261, while Pirh2F is missing C-terminal amino acids 227–261 and both isoforms harbor the RING domain; therefore, we speculate that ubiquitin ligase activity maybe reversed by them. Further studies are required to determine whether Pirh2E and Pirh2F functions in a manner similar to Pirh2A. Show more

Keywords: Pirh2, splice variants, hepatocellular carcinoma, gene therapy

DOI: 10.3233/BME-2012-0693

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 89-95, 2012

Authors: Li, Yue-Ying | Liu, Han-Han | Chen, Hong-Lei | Li, Yin-Ping

Article Type: Research Article

Abstract: Objective: To investigate the possibility of adipose-derived mesenchymal stem cells (ADSC) in the treatment of type 1 diabetes (T1D). Methods: ADSC were isolated from the adipotic tissue of abdomen in Sprague–Dawley rats (4–6 week-old,female) and expanded in vitro. Cells were then identified by testing their phenotypes through flow cytometry. Balb/c mice (8 week-old, male) were divided into 3 groups: T1D group, ADSC group and control group. Streptozocin (50 mg/kg·d) were injected intraperitoneally into mice of T1D group and ADSC group for 5 consecutive days to establish the T1D model. In ADSC group, ADSC were injected intravenously on day 3 …of STZ injection. In control group, only PBS was injected. Fasting blood glucose (FGB) level was examined once a week. At the end of the 4th week, animals were killed. The pathological changes of islet were showed by histochemistry through hematoxylin–eosin staining (HE staining). β cell insulin expression was detected by quantum dots immunofluorescence histochemistry. Results: After ADSC administration, FGB levels decreased significantly from the second week. Whereas FGB levels in T1D group increased significantly and continuously during the experimental period. Moreover, ADSC effectively suppressed pancreatic islet damage induced by STZ and increased the expression of insulin protein in pancreatic β cells. Conclusions: Intravenuously injected ADSC can prevent STZ induced β-cell destruction and decrease blood glucose level. Show more

Keywords: Adipose, mesenchymal stem cells, type 1 diabetes, pancreatic β cells

DOI: 10.3233/BME-2012-0694

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 97-103, 2012

Authors: Zhang, Lei | Ye, Jun-Song | Decot, Véronique | Stoltz, Jean-François | de Isla, Natalia

Article Type: Research Article

Abstract: Liver diseases have become one of the most important causes of morbidity and mortality in the world. Cell therapy and liver transplantation are though to be two treatment options well accepted. However, the shortage of cells sources in cytotherapy and the lack of liver donor in liver transplantation are the major obstacles for the performance of these treatment methods. It urged us to find new origins of extra-hepatic cells. A number of recent studies show that extra-hepatic mesenchymal stem cells (MSC) from different tissues can be differentiated into hepatocytes like cells (HLC). Several hepatic differentiation protocols of MSC have been …published in recent years, based on cellular stimulation with exogenous cytokines/growth factors, co-culture with fetal or adult hepatocytes, 2- or 3-dimensional (2D, 3D) matrices to favor differentiation. Independently from the starting stem cells population used, some minimal criteria must be fulfilled to ensure therapeutic success: in vitro expandability, expression of hepatic like surface markers, with hepatic cell functions, and minimal or absent immunogenicity in the recipient host. In this review, we focused on stem cells originated from bone marrow, umbilical cord and adipose tissue which are widely investigated in recent years and have been proved to have liver regenerative potential, the factors used to differentiate stem cells to hepatocyte-like cells and the methods used to investigate these cells. Show more

Keywords: Mesenchymal stem cells, hepatocytes, differentiation, bone marrow, umbilical cord, adipose tissue

DOI: 10.3233/BME-2012-0695

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 105-111, 2012

Authors: Ke, Min | Hu, Xin-Qian | Ouyang, Jingping | Dai, Bo | Xu, Yancheng

Article Type: Research Article

Abstract: Diabetic retinopathy (DR) is a severe complication of diabetes mellitus (DM) and often causes vision loss or even blindness. Vascular endothelial growth factor (VEGF) in the retina, which is mainly derived from Müller cells, is a crucial biological factor in the development of DR. Astragalin is extracted from Astragalus membranaceus and has many pharmacological properties. Studies showed that astragalin has beneficial effects on hyperglycemia. To evaluate the effect of astragalin in preventing and treating DR and determine astragalin's mechanism of action, Müller cells were collected from rat retina, cultured in vitro and identified using immunocytochemistry. They were divided into four …groups: the high glucose group (20 mmol/l), the normal control group, the astragalin group (400 mg/l) and the high glucose (20 mmol/l) + astragalin (400 mg/l) group. After 3 days of treatment, immunocytochemical and reverse transcription-polymerase chain reaction (RT-PCR) analysis of VEGF was carried out. Our results demonstrated that astragalin decreased the overexpression of VEGF in Müller cells and alleviated the effects caused by high glucose. Thus, astragalin has promising application in preventing and treating DR caused by DM. Show more

Keywords: Diabetic retinopathy, retinal Müller cells, astragalin, vascular endothelial growth factor

DOI: 10.3233/BME-2012-0696

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 113-119, 2012

Authors: Ni, Hong | Zeng, Siquan | Wu, Jing | Cheng, Xiangrong | Luo, Tao | Wang, Weiyang | Zeng, Weijuan | Chen, Yun

Article Type: Research Article

Abstract: Objective: To characterize the structure and to evaluate the cytotoxicity of cellulose nanowhiskers (CNW) prepared from cotton linters. Methods: A series of CNW dispersions was prepared by hydrolyzing cotton linters with sulfuric acid. The structure of CNW was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The cytotoxicity of CNW dispersions to L929 cells was preliminarily investigated by cell culture and MTT assay. Results: SEM and TEM observation showed that the original cotton litters have been successfully acid-hydrolyzed into cellulose nanowhiskers having needle- or short rod-like structure …with an average length of 250 nm and diameter of 10 nm. XRD patterns suggested that degree of crystalline in the CNW was much higher than that in the cotton linters as a result that the acid-hydrolysis process has removed the amorphous domains in the cotton linters. The results from MTT assay and cell morphology observation indicated that CNW with concentration from 0.01% to 0.2% had low toxicity to L929 cells, while cytotoxicity showed an increase tendency with an increase in the concentration of CNW. Conclusions: Cellulose nanowhiskers dispersion could be prepared from cotton linters by acid-hydrolysis process. CNW showed potential applications as nanobiomaterials due to its low cytotoxicity. Show more

Keywords: Cellulose, nanowhiskers, cytotoxicity

DOI: 10.3233/BME-2012-0697

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 121-127, 2012

Authors: Ma, Jun | Liu, Changhua | Li, Rui | Wang, Jia

Article Type: Research Article

Abstract: Novel chitosan (CS)/graphene oxide (GO) biocomposites (CS/GO-n) in the form of films are prepared in a casting and solvent evaporation method. Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractions (XRD), atomic force microscopy (AFM), tensile testing and moisture uptake are used to study the structure and properties of these biocomposites. The results indicated that the biocomposite containing 0.6 wt% GO exhibits high tensile strength (64.42 MPa) with a large elongation at break (38.80%). GO improved the mechanical properties and the water-resistance of chitosan-based biocomposites.

Keywords: Chitosan, graphene oxide, biocomposites, interaction, properties

DOI: 10.3233/BME-2012-0698

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 129-135, 2012

Authors: Eap, Sandy | Ferrand, Alice | Mendoza Palomares, Carlos | Hébraud, Anne | Stoltz, Jean-François | Mainard, Didier | Schlatter, Guy | Benkirane-Jessel, Nadia

Article Type: Research Article

Abstract: Tissue engineering aims at developing functional substitutes for damaged tissues by mimicking natural tissues. In particular, tissue engineering for bone regeneration enables healing of some bone diseases. Thus, several methods have been developed in order to produce implantable biomaterial structures that imitate the constitution of bone. Electrospinning is one of these methods. This technique produces nonwoven scaffolds made of nanofibers which size and organization match those of the extracellular matrix. Until now, seldom electrospun scaffolds were produced with thickness exceeding one millimeter. This article introduces a new kind of electrospun membrane called 3D scaffold of thickness easily exceeding one centimeter. …The manufacturing involves a solution of poly(ε-caprolactone) in DMF/DCM system. The aim is to establish parameters for electrospinning in order to characterize these 3D scaffolds and, establish whether such scaffolds are potentially interesting for bone regeneration. Show more

Keywords: Tissue engineering, bone regeneration, electrospinning, 3D scaffold, nanofibers, polycaprolactone

DOI: 10.3233/BME-2012-0699

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 137-141, 2012

Authors: Wang, Xiaomei | Shi, Na | Chen, Yan | Li, Chen | Du, Xinshen | Jin, Weihua | Chen, Yun | Chang, Peter R.

Article Type: Research Article

Abstract: Objective: To improve the hemocompatibility of chitosan/soy protein isolate composite membranes by heparinization. Methods: Chitosan/soy protein isolate membranes (ChS-n, n=0, 10 and 30, corresponding to the soy protein isolate content in the membranes) and heparinized ChS-n membranes (HChS-n) were prepared by blending in dilute HAc/NaAc solution. The hemocompatibility of ChS-n and HChS-n membranes were comparatively evaluated by measuring surface heparin density, blood platelet adhesion, plasma recalcification time (PRT), thrombus formation and hemolysis assay. Results: The surface heparin density analysis showed that heparinized chitosan/SPI soy protein isolate membranes have been successfully prepared by blending. The density of heparin on …the surface of HChS-n membranes was in the range of 0.67–1.29 μg/cm2 . The results of platelet adhesion measurement showed that the platelet adhesion numbers of HChS-n membranes were lower than those of the corresponding ChS-n membranes. The PRT of the HChS-0, HChS-10 and HChS-30 membranes were around 292, 306 and 295 s, respectively, which were longer than the corresponding ChS-0 (152 s), ChS-10 (204 s) and ChS-30 (273 s) membranes. The hemolysis rate of HChS-n membranes was lower than 1%. Conclusion: The hemocompatibility of ChS membranes could be improved by blending with heparin. Compared with ChS membranes, HChS membranes showed lower platelet adhesion, longer PRT, higher BCI, significant thromboresistivity and a lower hemolysis rate due to the heparinization. This widens the application of chitosan and soy protein-based biomaterials that may come in contact with blood. Show more

Keywords: Chitosan, soy protein isolate, membrane, heparinization, hemocompatibility

DOI: 10.3233/BME-2012-0700

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 143-150, 2012

Authors: Yu, Jingwen | Zhao, Fei | Wen, Xianmei | Ding, Qiong | Zhang, Ling | Wang, Ge

Article Type: Research Article

Abstract: Dental cast alloys have been widely used in modern dental restoration. However, due to oral complex environment and individual differences, continuous corrosion of alloys occurs. As a result, metal ions like nickel ion (Ni3+ ) can be released from alloys for prolonged time. This can lead to chronic adverse effects on the surrounding tissues and cells. In order to evaluate the cytotoxic effects of nickel ion on human gingival fibroblasts and explore the mechanism, we observed the effects of the ion salt solution on the proliferation of cultured cells in vitro. The IC50 value of Ni3+ was 389.6 …μmol/l. Then we studied the mechanism of inhibition proliferation of Ni3+ on cultured cells by flow cytometry, the results have shown that Ni3+ induced apoptosis of cultured cells with the pretreatment process prolonged. Besides, we also detected the expression level of cysteinyl aspartate specific protease-3 (caspase-3) mRNA which was shown activated. As a conclusion, the inhibition effect of Ni3+ on the proliferation of gingival fibroblasts was partly due to its potential of inducing apoptosis, and the mechanism of apoptosis is via the caspase-3 activation. The further studies will be fulfilled by animal experiment or evidence-based medicine method. Show more

Keywords: Dental casting alloys, corrosion, nickel ion, cytotoxicity, apoptosis

DOI: 10.3233/BME-2012-0701

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 151-157, 2012

Authors: Dumas, D. | Hupont, S. | Huselstein, C. | de Isla, N. | Rousseau, M. | Werkmeister, E. | Magdalou, J. | Menu, P. | Stoltz, J.-F.

Article Type: Research Article

Abstract: For this study, we have considered a new large field of view imaging dedicated to matrix collagen (no stained samples). To integrate a multidimensional scale (non-sliced samples), a femtosecond oscillator (two photon excitation laser) has been coupled with a large field optical setup to collect SHG signal. We introduced an index (F–SHG) based on decay time response measured by TCSPC for, respectively, Fluorescence (F) and Second Harmonic Generation (SHG) values. For samples where protein collagen is the major component of extracellular matrix (skin) or not (nacre), we compared the index distribution (from 2 to 12) obtained with large field optical …setup. In this work, we showed for the first time that multiscale large field imaging combined to multimodality approaches (SHG-TCSPC) could be an innovative and non invasive technique to detect and identify some biological interest molecules (collagen) in biomedical topics. Show more

Keywords: Multiphoton, second harmonic generation, collagen, extracellular matrix

DOI: 10.3233/BME-2012-0702

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 1-3, pp. 159-162, 2012