Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Hiroyuki Ijima Last modified date:2022.05.19

Professor / Molecular and Biochemical Systems Engineering / Department of Chemical Engineering / Faculty of Engineering


Papers
1. Yusuke Sakai, Yoshihiro Kubo, Nana Shirakigawa, Yoshinori Kawabe, Masamichi Kamihira, and Hiroyuki Ijima, Promotion of cyst formation from a renal stem cell line using organ-specific extracellular matrix gel format culture system, Gels, https://doi.org/10.3390/gels8050312, 8, Article No.312, 11pages, Accepted (2022/5/17), 2022.05, Researchers have long awaited the technology to develop an in vitro kidney model. Here, we establish a rapid fabricating technique for kidney-like tissues (cysts) using a combination of or-gan-derived extracellular matrix (ECM) gel format culture system and a renal stem cell line (CHK-Q cells). CHK-Q cells, which are spontaneously immortalized from the renal stem cells of Chinese hamster, formed renal cyst-like structures in a type-I collagen gel sandwich culture on day 1 of culture. The cysts fused together and expanded while maintaining three-dimensional structures. The expression of genes related to kidney development and maturation was increased compared with that in a traditional monolayer. Under kidney-derived ECM (K-ECM) gel format culture system, cyst formation and maturation were induced rapidly. Gene expressions involved in cell polarities, especially for important material transporters (typical markers Slc5a1 and Kcnj1), were restored. K-ECM composition were important triggers for CHK-Q cells to promote kidney-like tissue formation and maturation. We have established a renal cyst model, which rapidly expressed mature kidney features, via the combination of K-ECM gel format culture system and CHK-Q cells..
2. Jannatul Fardous, Yuuta Inoue, Kozue Yoshida, Fumiyasu Ono, Akihiro Higuchi, Hiroyuki Ijima, Delivery of hydrophobic drugs to the posterior ocular region by gel-in-water nanoemulsion, TVST (Translational Vision Science & Technology), https://doi.org/10.1167/tvst.11.5.16, 11, 5, Article 16, 11pages, Accepted (2022/4/18), 2022.05, Purpose. The aim of the present study was to develop a nanogel emulsion, as a minimally invasive, safe, and effective treatment alternative for posterior ocular diseases.
Methods. A gel-in-water (G/W) nanoemulsion was developed by ultrasonication using beeswax as an organogelator. Different physicochemical properties were evaluated along with particle size analysis by dynamic light scattering. In vitro biocompatibility of G/W nanoemulsion using rat hepatocytes and human umbilical vein endothelial cells (HUVECs) and in vivo corneal permeability as eye drops were investigated.
Results. The nanogel emulsion was monodispersed with a polydispersity index and particle diameter of approximately 0.2 and 200 nm, respectively. The zeta potential value of −8.1 mV suggested enhanced stability and improved retinal permeability of nanoparticles. The prepared nanoemulsion was found to be biocompatible with hepatocytes and HUVECs in vitro. Moreover, in vivo study demonstrated high permeability of G/W nanoemulsion to the retinal layer with no ocular irritation.
Conclusion. G/W nanoemulsions have the potential for topical drug delivery in the posterior eye segment with maximum therapeutic efficacy.
Translational relevance. Organogel nanodispersion is a new concept to deliver hydrophobic drugs to the posterior segment of eyes as a novel drug delivery system..
3. Jannatul Fardous, Yuji Omoso, Kozue Yoshida, Fumiyasu Ono, Md Kawchar Ahmed Patwary, Hiroyuki Ijima, Gel-in-Water Nanodispersion for Potential Application in Intravenous Delivery of Anticancer Drugs, Journal of Bioscience and Bioengineering, https://doi.org/10.1016/j.jbiosc.2021.10.001, 133, 2, 174-180, Accepted (2021/10/01), 2022.02, Organogels are semi-solid systems that can gel organic liquids at low concentrations. The use of organogels in drug delivery has grown rapidly in the last decade owing to their fibrous microstructure and suitability for different routes of administration. The current study is characterized by nanogel dispersion (NGD) development based on emulsion technology. The efficiency of this organogel based NGD as a carrier for anticancer drugs was assessed both in vitro and in vivo. 12-Hydroxystearic acid formed an organogel with lipiodol and encapsulated the anticancer drug paclitaxel. The gel-in-water (G/W) nanodispersion was prepared via ultrasonication and stabilized by a nonionic surfactant. The results showed that the organogel enabled sustained drug release from G/W nanodispersion over time, along with enhanced cellular uptake. The prepared G/W nanodispersion was found to be biocompatible with mouse hepatocytes and fibroblast cells in vitro, whereas paclitaxel-loaded G/W nanodispersion showed cytotoxicity (*p <0.05) against lung cancer (A549) cell lines. Similarly, intravenous administration of paclitaxel-loaded G/W nanodispersion exerts an anticancer effect against lung cancer in vivo, with a significant decrease in tumor volume (*p <0.05). Therefore, the proposed G/W nanodispersion could be a promising carrier for chemotherapy agents with sustained drug release and better therapeutic outcomes against cancer..
4. Jannatul Fardous, Emiko Yamamoto, Yuji Omoso, Seiya Nagao, Yuuta Inoue, Kozue Yoshida, Yasuhiro Ikegami, Zhang Yi, Nana Shirakigawa, Fumiyasu Ono, Hiroyuki Ijima, Development of a gel-in-oil emulsion as a transdermal drug delivery system for successful delivery of growth factors, Journal of Bioscience and Bioengineering, https://doi.org/10.1016/j.jbiosc.2021.03.015, 132, 1, 95-101, Accepted (2021/03/26), 2021.07, Growth factors (GFs) are indispensable in regenerative medicine because of their high effectiveness. However, as GFs degenerate easily, the development of a suitable carrier with improved stability for GFs is necessary. In this study, we developed a gel-in-oil (G/O) emulsion technology for the transdermal delivery of growth factors. Nanogel particles prepared with heparin-immobilized gelatin that can bind growth factors were dispersed in isopropyl myristate. The particle size of the G/O emulsion could be controlled by changing the surfactant concentration, volume ratio of the water phase to the oil phase, and gelatin concentration. In vitro skin penetration studies showed better penetration through the stratum corneum of fluorescent proteins containing G/O emulsions than of the aqueous solution of GF. Similarly, an in vivo study showed an angiogenesis-inducing effect after transdermal application of GF-immobilized G/O emulsion. Angiogenesis in mice was confirmed owing to both an increased blood vessel network and higher hemoglobin content in the blood. Therefore, the G/O emulsion could be a promising carrier for GFs with better stability and can effectively deliver GFs at the target site..
5. Kozue Yoshida, Fumiyasu Ono, Takehiro Chouno, Shota Nakada, Yasuhiro Ikegami, Nana Shirakigawa, Yusuke Sakai, Hiroyuki Ijima, Creation of a novel lipid-trehalose derivative showing positive interaction with the cell membrane and verification of its cytoprotective effect during cryopreservation, Journal of Bioscience and Bioengineering, https://doi.org/10.1016/j.jbiosc.2021.03.010, 132, 1, 71-80, Accepted (2021/3/23), 2021.07, Cryopreservation is important for enabling long-term cell preservation. However, physical damage due to ice crystal formation and membrane permeation by dimethyl sulfoxide (DMSO) severely affects cryopreserved cell viability. To ensure cell survival and functional maintenance after cryopreservation, it is important to protect the cell membrane, the most vulnerable cell component, from freeze-thaw damage. This study aimed to create a glycolipid derivative having a positive interaction with the cell membrane and cytoprotective effects. As a result, we synthesized a novel trehalose derivative, Oleyl-Trehalose (Oleyl-Treh), composed of trehalose and oleyl groups. Its use led to increased viable cell counts when used with DMSO in a non-cytotoxic concentration range (1.6 nM–16 µM). Oleyl-Treh significantly improved viability and liver-specific functions of hepatocytes after cryopreservation, including albumin secretion, ethoxyresorufin-O-deethylase activity (an indicator of cytochrome P450 family 1 subfamily A member 1 activity), and ammonia metabolism. Oleyl-Treh could localize trehalose to the cell membrane; furthermore, the oleyl group affected cell membrane fluidity and exerted cryoprotective effects. This novel cryoprotective agent, which shows a positive interaction with the cell membrane, provides a unique approach toward cell protection during cryopreservation..
6. Jannatul Fardous, Yuji Omoso, Akshat Joshi, Kozue Yoshida, Md Kawchar Ahmed Patwary, Fumiyasu Ono, Hiroyuki Ijima, Development and characterization of gel-in-water nanoemulsion as a novel drug delivery system, Materials Science & Engineering C, https://doi.org/10.1016/j.msec.2021.112076, No.112076 (10 pages), Accepted (2021/03/07), 2021.05, The effective delivery of anti-cancer drugs with minimal side effects and better therapeutic efficacy has remained an active area of research for many decades. Organogels have gained attention in recent years due to their high bioavailability, no first-pass metabolism, and rapid action. Considering this, in the current study an organogel based nanoemulsion was developed aiming to effectively deliver hydrophobic drugs via encapsulation within in situ gellable organogel droplets, termed as gel-in-water (G/W) nanoemulsion. G/W nanoemulsion was prepared using a combination of lipiodol and organogeltor 12-Hydroxystearic acid (12-HSA) as inner gel phase; dispersed in water by ultrasonication and stabilized with polyoxyethylene hydrogenated castor oil (HCO-60) as surfactant. The prepared nanoemulsion showed high drug loading efficiency (≈ 97%) with a mean diameter of 206 nm. Lower polydispersity index (PdI) value (≈ 0.1) suggests monodispersed nature of G/W nanoemulsion in the continuous phase. G/W nanoemulsion was found stable over six months in terms of particle size, zeta potential and pH at different storage temperatures. There was no cytotoxic effect of prepared G/W nanoemulsion on primary hepatocytes in vitro. In contrast, paclitaxel-loaded G/W showed a significant decrease in melanoma cell growth (*p <0.05) both in vitro and in vivo. Our results support the hypothesis that organogel based nanoemulsions can be a promising drug delivery system..
7. Kozue Yoshida, Shunsuke Nakamura, Hiroki Sakamoto, Mika Kondo, Takehiro Chouno, Yasuhiro Ikegami, Nana Shirakigawa, Hiroshi Mizumoto, Yo-ichi Yamashita, Hideo Baba, Hiroyuki Ijima, Normothermic machine perfusion system satisfying oxygen demand of liver could maintain liver function more than subnormothermic machine perfusion, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2020.08.011., 131, 1, 107-113, Accepted (2020/8/24), 2021.01, Liver transplantation plays an important role in the medical field. To improve the quality of a donor liver, there is a need to establish a preservation system to prevent damage and maintain liver function. In response to this demand, machine perfusion (MP) has been proposed as a new liver preservation method instead of the conventional static cold storage. There is controversy about the optimal MP temperature of the donor liver. Since the oxygen consumption of the liver differs depending on the temperature, construction of a system that satisfies the oxygen demand of the liver is crucial for optimizing the preservation temperature. In this study, a MP system, which satisfies the oxygen demand of liver at each temperature, was constructed using an index of oxygen supply; the overall volumetric oxygen transfer coefficient, the amount of oxygen retention of perfusate and oxygen saturation. Both subnormothermic MP (SNMP, 20-25 °C) and normothermic MP (NMP, 37 °C) could maintain liver viability at a high level (94%). However, lactate metabolism of the liver during NMP was more active than that during SNMP. Furthermore, the ammonia metabolism of liver after NMP was superior to that after SNMP. Hence, NMP, which maintains the metabolic activity of the liver, is more suitable for preservation of the donor liver than SNMP, which suppresses the metabolic activity. In summary, normothermia is the optimal temperature for liver preservation, and we succeeded in constructing an NMP system that could suppress liver damage and maintain function..
8. Yasuhiro Ikegami, Hideyuki Mizumachi, Kozue Yoshida, Hiroyuki Ijima, Heparin-conjugated collagen as a potent growth factor-localizing and stabilizing scaffold for regenerative medicine, Regenerative Therapy, 10.1016/j.reth.2020.10.002., 15, 236-242, Accepted (2020/10/1), 2020.12.
9. Kozue Yoshida, Fumiyasu Ono, Takehiro Chouno, Bual Ronald Perocho, Yasuhiro Ikegami, Nana shirakigawa, Hiroyuki Ijima, Cryoprotective enhancing effect of very low concentration of trehalose on the functions of primary rat hepatocytes, Regenerative Therapy, 10.1016/j.reth.2020.08.003., 15, 173-179, Accepted (2020/8/17), 2020.12, [Introduction] Cells have various applications in biomedical research. Cryopreservation is a cell-preservation technique that provides cells for such applications. After cryopreservation, sensitive cells, such as primary hepatocytes, suffer from low viability due to the physical damage caused by ice crystals, highlighting the need for better methods of cryopreservation to improve cell viability. Given the importance of effectively suppressing ice crystal formation to protect cellular structure, trehalose has attracted attention as cryoprotectant based on its ability to inhibit ice crystal formation; however, trehalose induces osmotic stress. Therefore, to establish a cell-cryopreservation technique, it is necessary to provide an optimal balance between the protective and damaging effects of trehalose.
[Methods] In this study, we evaluated the effects of osmotic stress and ice crystal formation on the viability and function of primary rat hepatocytes at wide range of trehalose concentration.
[Results] There was no osmotic stress at very low concentrations (2.6 μM) of trehalose, and 2.6 μM trehalose drives the formation of finer ice crystals, which are less damaging to the cell membrane. Furthermore, we found that the number of viable hepatocytes after cryopreservation were 70% higher under the 2.6 μM trehalose-supplemented conditions than under the dimethyl sulfoxide-supplemented conditions. Moreover, non-cryopreserved cells and cells cryopreserved with trehalose showed comparable intracellular dehydrogenase activity.
[Conclusions] We showed that trehalose at very low concentrations (2.6 μM) improved dramatically viability and liver function of hepatocyte after cryopreservation..
10. Akshat Joshi, Zhe Xu, Yasuhiro Ikegami, Kozue Yoshida, Yusuke Sakai, Akshay Joshi, Tejinder Kaur, Yosuke Nakao, Yo-ichi Yamashita, Hideo Baba, Shinichi Aishima, Neetu Singh, Hiroyuki Ijima, Exploiting synergistic effect of externally loaded bFGF and endogenous growth factors for accelerated wound healing using heparin functionalized PCL/gelatin co-spun nanofibrous patches, Chemical Engineering Journal, https://doi.org/10.1016/j.cej.2020.126518, 404, 1-13, Article 126518, Accepted (2020/7/30), Available online 03 August 2020, 2020.11, Growth factors (GFs) are signaling molecules that are principle mediators in tissue regeneration. Biomaterial scaffolds employed as wound dressings are often hampered by their limitations to deliver GFs exogenously due to their instability and low half-life. The key to overcome this challenge lies in the better organization and use of endogenous pro-regenerative GFs released at regenerative site, with an aim to minimize the sole dependency on exogenous factors. Considering such challenges, this research utilizes the exogenous and endogenous GFs sequestering capability of heparin functionalized PCL/gelatin co-spun nanofabrics to mediate synergistically driven tissue regeneration by utilizing combined therapeutic effect of exogenous and endogenous GFs, and thereby minimizing the sole dependency on exogenous GFs for tissue regeneration. Basic fibroblast growth factor (bFGF) was chosen as GF for exogenous loading whereas vascular endothelial growth factor (VEGF) was chosen as a representative example to demonstrate the endogenous pro-regenerative GF sequestration capability of fabricated nanofabrics. From our results, the fabricated nanofabrics showed loading efficiency of 80% for exogenous bFGF and can sequester 15-fold more amount of endogenous VEGF compared to non-heparin functionalized nanofibrous dressings. When applied as wound dressings, heparin functionalized nanofibers showed better therapeutic capability compared to control groups that were treated using patches without heparin functionalization, indicating endogenously driven tissue regeneration. This was indicated by significant higher number of newly formed skin appendages, lesser scarring and lower inflammatory levels in newly formed granulation. Additionally, further improvements in therapeutic effect was observed when exogenous bFGF was employed indicating effectiveness of synergistically mediated tissue regeneration..
11. Yasuhiro Ikegami, Hiroyuki Ijima, Development of heparin-conjugated nanofibers and a novel biological signal by immobilized growth factors for peripheral nerve regeneration, Journal of Bioscience and Bioengineering, https://doi.org/10.1016/j.jbiosc.2019.09.004, 129, 3, 354-362, Accepted (2019/9/5), 2020.03.
12. Akshat Joshi, Zhe Xu, Yasuhiro Ikegami, Soichiro Yamane, Masanori Tsurashima, Hiroyuki Ijima, Co-culture of mesenchymal stem cells and human umbilical vein endothelial cells on heparinized polycaprolactone/gelatin co-spun nanofibers for improved endothelium remodeling, International Journal of Biological Macromolecules, https://doi.org/10.1016/j.ijbiomac.2020.02.163, 151, 186-196, Accepted (2020/2/15), 2020.02, Endothelization of a tissue-engineered substrate is important for its application as an artificial vascular graft. Despite recent advancements in artificial graft fabrication, a graft of b5mmis difficult to fabricate owing to insufficient endothelization that results in thrombosis after transplantation. We aimed to perform a co-culture of adipose-derived mesenchymal stem cells (MSCs) with human umbilical vein endothelial cells (HUVECs) on antithrombogenic polycaprolactone (PCL)/heparin-gelatin co-spun nanofibers to evaluate the role of coculturing in promoting quick endothelization of vascular substrateswithout surface modification by growth factors or other ECM proteins that trigger the endothelization process. Using a co-axial electrospinning technique, we attempted to fabricate our scaffold balancing between mechanical properties and biocompatibility. Antithrombogenic characteristics were then imparted to the fabricated nanofiber substrate by grafting of heparin. Finally, we performed a co-culture of MSCs and HUVECs on the fabricated co-spun nanofiber substrate to obtain proper endothelization of our material under the in-vitro culture. Staining for CD-31 at seven days of culture revealed enhanced CD-31 expression under the co-culture condition; actin staining revealed healthy cobblestone HUVECmorphology, suggesting thatMSCs can aid in proper endothelization. Hence,we conclude that co-culture is effective for quick endothelization of vascular substrates..
13. Ronald Bual and Hiroyuki Ijima, Intact extracellular matrix components promotes maintenance of liver-specific functions and larger aggregates formation of primary rat hepatocytes, Regenerative Therapy, https://doi.org/10.1016/j.reth.2019.08.006, 11, 258-268, Accepted (2019/8/30), 2019.12, The extracellular matrix (ECM) in a liver-specific extracellular matrix (L-ECM) scaffold facilitates hepatocyte viability and maintains hepatocyte functions in vitro. However, whether an intact composition of ECM is required for an efficient ECM-based substrate design remains to be clarified. In this study, two LECM hydrogels, namely L-ECM I and L-ECM II, were prepared by pepsin solubilization at 4 ℃ and 25 ℃, respectively. The solubility at 4 ℃ was 50% whereas that at 25 C was 95%, thus indicating well-preserved L-ECM. Analysis confirmed higher ECM protein components (especially collagen) in L-ECM II, along with denser fiber network and larger fiber diameter. L-ECM II gel exhibited high compression strength and suitable viscoelastic properties. Furthermore, hepatocytes in L-ECM II showed higher expression of liver specific functions in 3D culture and wider spread while maintaining the cell-cell contacts in 2D culture. Therefore, an intact L-ECM is important to realize effective substrates for liver tissue engineering..
14. Hiroki Sakamoto, Nana Shirakigawa, Ronald Perocho Bual, Yukako Fukuda, Shunsuke Nakamura, Tatsunori Miyata, Takanobu Yamao, Yo-ichi Yamashita, Hideo Baba, Hiroyuki Ijima, A novel evaluation system for whole organ engineered-liver graft by ex vivo application to a highly reproducible hepatic failure rat model, Journal of Artificial Organs, https://doi.org/10.1007/s10047-019-01106-6, 22, 3, 222-229, Accepted (2019/May/2), 2019.09, In recent years, studies on liver graft construction using the decellularized liver as a template for transplantation therapy have attracted much attention. However, the therapeutic effect of constructed liver grafts in hepatic failure has not been evaluated. Therefore, we aimed to develop a novel evaluation system demonstrating the curative effect of a constructed liver graft in animals with hepatic failure. First, we developed a highly reproducible rat model of hepatic failure by combining 80% partial hepatectomy with warm ischemia. In this model, severity could be controlled by the warm ischemic period. We also constructed a liver graft by recellularization of decellularized liver, and confirmed the ammonia metabolic function in the graft in vitro as one of the most important functions for recovery from hepatic failure. The graft was then applied to our developed-hepatic failure rat model using a blood extracorporeal circulation system. In this application, the graft metabolized the ammonia in the blood of animals with hepatic failure and was thus suggested to be effective for the treatment of hepatic failure. In summary, a novel evaluation system for whole organ engineered-liver graft as a preliminary stage of transplantation was developed. This system was expected to provide much information about the curative effect of a constructed liver graft..
15. Hiroyuki Ijima, Shintaro Nakamura, Ronald Perocho Bual, Kozue Yoshida, Liver-specific ECM hydrogel promotes liver-specific functions of hepatocytes in vitro and survival of transplanted hepatocytes in vivo, Journal of Bioscience and Bioengineering, https://doi.org/10.1016/j.jbiosc.2019.02.014, 128, 3, 365-372, 2019.09, A solubilized liver-specific extracellular matrix (L-ECM) substratum was obtained by decellularization of porcine liver using Triton X-100 and pepsin treatments. The L-ECM was able to immobilize hepatocyte growth factor at a high efficiency of 87%. L-ECM gelled spontaneously in a physiologically neutral environment. Primary hepatocytes embedded in the L-ECM gel showed a high albumin synthesis activity and EROD activity even at 3 weeks in culture. In addition, the L-ECM gel-embedded hepatocytes implanted subcutaneously into partial hepatectomized rats showed a high survival rate (18%) and formed a large liver tissue-like structure. Their efficiencies of EROD activity and large liver tissue-like structure formation were about twice those of collagen gel-embedded hepatocytes. Based on these results, we clarified the effectiveness of L-ECM gel as a substrate for hepatocyte culture and transplantation..
16. Safrina Dyah Hardiningtyas, Seiya Nagao, Emiko Yamamoto, Nana Shirakigawa, Rie Wakabayashi, Masahiro Goto, Hiroyuki Ijima and Noriho Kamiya, A nano-sized gel-in-oil suspension for transcutaneous protein delivery, International Journal of Pharmaceutics, https://doi.org/10.1016/j.ijpharm.2019.118495, 567, 118495, 1-6, 2019.08, We developed a new oil-based delivery system for transdermal protein delivery, a gel-in-oil (G/O) nanosuspension, where gelatin-based hydrogel was coated with hydrophobic surfactants. The high entrapment efficiency of a model protein, phycocyanin (PC), into nano-sized gelatin hydrogel particles was achieved. Spectroscopic evaluation of PC suggested that the G/O nanosuspension could retain the functional form of PC in isopropyl myristate. In vitro skin permeation studies showed that the G/O nanosuspension facilitated the delivery of PC through the stratum corneum of Yucatan micropig skin..
17. Jaeyong Cho, Yukako Fukuda, Nana Shirakigawa and Hiroyuki Ijima, Examination of conditions for optimized decellularized liver preparation”, Asian Journal of Research in Biochemistry, 5, 1, 1-8, Article no.AJRB.49673
Accepted 26 June 2019
Published 12 July 2019, 2019.07, Aims: The main aim of our study was to examine the concentration of surfactant that can cause significant disruption of the resulting decellularized liver structure. Furthermore, it is our goal to
determine the suitable solvent that can boost the potential of each surfactant.
Methodology: The porcine liver disks of 8-mm diameter and 2-mm thickness were prepared. These were soaked in aqueous solution of either sodium dodecyl sulfate (SDS) or Triton X-100 (TX), and
placed on a rotational shaking machine (100 rpm).
Results: TX was unable to completely remove the cellular components under any of our experimental conditions. The salt concentration did not affect the decellularization in TX. The pH
buffer, however, was found to affect the decellularization. Also, in the solvent study, the conditions under which SDS effectively exerted power were not the salt concentration and pH, but the condition
that was close to water. We also confirmed that the shrinkage of tissue occurred when decellularization with 0.1% SDS in CMF-PBS. However, 0.1% SDS in distilled water didn't cause the
deformation of tissue. This is considered to be due to the low salt concentration of solvent.
Conclusion: This work establishes the concentration range of the surfactant that causes the collapse of the cellular structure during decellularization. In addition, the solvent suitable for each
surfactant has also been established..
18. Tuyajargal Iimaa, Takaaki Hirayama, Nana Shirakigawa, Daisuke Imai, Takanobu Yamao, Yo-ichi Yamashita, Hideo Baba, Hiroyuki Ijima, Antibacterial-agent-immobilized gelatin hydrogel as a 3D scaffold for natural and bioengineered tissues, Gels, https://doi.org/10.3390/gels5020032, 5, 32, 1-14, Accepted: 9 June 2019; Published: 11 June 2019
, 2019.06, Hydrogels and their medical applications in tissue engineering have been widely studied due to their three-dimensional network structure, biocompatibility, and cell adhesion. However, the development of an artificial bile duct to replace the recipient's tissue is still desired. Some challenges remain in the tissue engineering field, such as infection due to residual artifacts. In other words, at present, there are no established technologies for bile duct reconstruction as strength and biocompatibility problems. Therefore, this study investigated hydrogel as an artificial bile duct base material that can replace tissue without any risk of infectious diseases. First, an antibacterial agent (ABA), Finibax (an ABA used for the clinical treatment of biliary tract infection), was immobilized in gelatin using a crosslinking agent, and the antibacterial properties of the gel and its sustainability were tested. Furthermore, the immobilized amount and the improvement of the proliferation of the human umbilical vein endothelial cells (HUVECs) were cultured as the ABA-Gelatin hydrogel was introduced to prepare a 3D scaffold. Finally, we performed hematoxylin and eosin (H&E) staining after subcutaneous implantation in the rat. Overall, the ABA-Gelatin hydrogel was found to be viable for use in hydrogel applications for tissue engineering due to its good bactericidal ability, cell adhesion, and proliferation, as well as having no cytotoxicity to cells..
19. Tuyajargal Iimaa, Ikegami Yasuhiro, Ronald Bual, Nana Shirakigawa, Hiroyuki Ijima, Analysis of sulfated glycosaminoglycans in ecm scaffolds for tissue engineering applications: Modified alcian blue method development and validation, Journal of Functional Biomaterials, https://doi.org/10.3390/jfb10020019, 10, 19, 1-15, Accepted: 29 April 2019; Published: 30 April 2019, 2019.04, Accurate determination of the amount of glycosaminoglycans (GAGs) in a complex mixture of extracellular matrix (ECM) is important for tissue morphogenesis and homeostasis. The aim of the present study was to investigate an accurate, simple and sensitive alcian blue (AB) method for quantifying heparin in biological samples. A method for analyzing heparin was developed and parameters such as volume, precipitation time, solvent component, and solubility time were evaluated. The AB dye and heparin samples were allowed to react at 4 ℃ for 24 h. The heparin-AB complex was dissolved in 25 N NaOH and 2-Aminoethanol (1:24 v/v). The optical density of the solution was analyzed by UV-Vis spectrometry at 620 nm. The modified AB method was validated in accordance with U.S. Food and Drug Administration guidelines. The limit of detection was found to be 2.95 µg/mL. Intraday and interday precision ranged between 2.14–4.83% and 3.16–7.02% (n = 9), respectively. Overall recovery for three concentration levels varied between 97 ± 3.5%, confirming good accuracy. In addition, this study has discovered the interdisciplinary nature of protein detection using the AB method. The basis for this investigation was that the fibrous protein inhibits heparin-AB complex whereas globular protein does not. Further, we measured the content of sulfated GAGs (sGAGs; expressed as heparin equivalent) in the ECM of decellularized porcine liver. In conclusion, the AB method may be used for the quantitative analysis of heparin in ECM scaffolds for tissue engineering applications..
20. Ronald Bual, Haruna Kimura, Yasuhiro Ikegami, Nana Shirakigawa, Hiroyuki Ijima, Fabrication of liver-derived extracellular matrix nanofibers and functional evaluation in in vitro culture using primary hepatocytes, Materialia, doi.org/10.1016/j.mtla.2018.11.014, 4, 518-528, 2018.12, Fabrication of functional scaffolds is one of the main goals of tissue engineering, particularly scaffolds mimicking the native extracellular matrix (ECM) and stimulating a microenvironment that supports cell growth and function. In this study, a scaffold was developed using liver-derived ECM (L-ECM), gelatin, and polycaprolactone (PCL) by conventional electrospinning. This study aimed to improve the gelatin-PCL nanofiber blend by incorporating L-ECM. The morphology of the nanofibrous scaffold was investigated by scanning electron microscopy. Characterizations such as Fourier transform infrared spectroscopy (FTIR), tensile strength test, and water contact angle analysis revealed the favorable characteristics of the scaffold. Particularly, the FTIR spectra confirmed the presence of L-ECM, gelatin, and PCL, even after crosslinking treatment, while tensile strength analysis revealed suitable mechanical properties and water contact angle measurement showed the improved hydrophilic characteristics of the scaffold. The biocompatibility of the composite nanofibers was evaluated by in vitro culture of primary hepatocytes. Phase-contrast microscope images verified that the L-ECM nanofibers improved hepatocyte adhesion and facilitated the formation of a tissue-like structure. Moreover, high liver-specific functions were obtained in L-ECM nanofibers compared to gelatin/PCL nanofibers. Thus, L-ECM nanofibers can be used in tissue engineering, particularly in liver regeneration..
21. Hiroyuki Ijima, Shintaro Nakamura, Ronald Bual, Nana Shirakigawa, Shuichi Tanoue, Physical properties of the extracellular matrix of decellularized porcine liver, Gels, doi:10.3390/gels4020039, 4, 2, 39-53, 2018.05, The decellularization of organs has attracted attention as a new functional methodology for regenerative medicine based on tissue engineering. In previous work we developed an L-ECM (Extracellular Matrix) as a substrate-solubilized decellularized liver and demonstrated its effectiveness as a substrate for culturing and transplantation. Importantly, the physical properties of the substrate constitute important factors that control cell behavior. In this study, we aimed to quantify the physical properties of L-ECM and L-ECM gels. L-ECM was prepared as a liver-specific matrix substrate from solubilized decellularized porcine liver. In comparison to type I collagen, L-ECM yielded a lower elasticity and exhibited an abrupt decrease in its elastic modulus at 37 °C. Its elastic modulus increased at increased temperatures, and the storage elastic modulus value never fell below the loss modulus value. An increase in the gel concentration of L-ECM resulted in a decrease in the biodegradation rate and in an increase in mechanical strength. The reported properties of L-ECM gel (10 mg/mL) were equivalent to those of collagen gel (3 mg/mL), which is commonly used in regenerative medicine and gel cultures. Based on reported findings, the physical properties of the novel functional substrate for culturing and regenerative medicine L-ECM were quantified..
22. Apeksha Damania, Anupam Kumar, Arun Teotia, Kimura Haruna, Masamichi Kamihira, Hiroyuki Ijima, Shiv Kumar Sarin, Ashok Kumar, Decellularized liver matrix modified cryogel scaffolds as potential hepatocyte carriers in bioartificial liver support systems and implantable liver constructs, ACS Applied Materials & Interfaces, doi: 10.1021/acsami.7b13727., 10, 1, 114-126, Epub 2017 Dec 29., 2018.01.
23. Hiroyuki Ijima, Practical hybrid artificial liver support system and whole liver engineering, Proceedings of 5th International Symposium & Exhibition on Aqua Science and Water Resources (ISASWR'17), 50-53, 2017.08, Development of a novel therapeutic treatment is indispensable for the life-saving of severe liver failure patients. In this study, a hybrid artificial liver support system consisting of a porous substrate packed bed type module in which hepatocytes spheroid was immobilized was developed. In preclinical animal experiments using warm ischemic liver failure pigs, this system realized high expression of liver functions and remarkable prolongation of survival time. On the other hand, a prototype of Whole Liver Engineered-Liver for transplantation was constructed using rats as model animals. Blood ammonia was well metabolized in blood circulation culture containing this graft. Furthermore, the survival time of liver failure rats was applied was markedly prolonged by applying this graft. From the above results, the effectiveness of the practical hybrid artificial liver support system and Whole Organ Engineered-Liver graft was demonstrated..
24. Takayuki Nagai, Yasuhiro Ikegami, Hideyuki Mizumachi, Nana Shirakigawa, Hiroyuki Ijima, Development of an in situ evaluation system for neural cells using ECM-modeled gel culture, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2017.04.018, 124, 4, 430-438, Final version published online: 04-Sep-2017, 2017.09.
25. Apeksha Damania, Mohsin Hassan, Nana Shirakigawa, Hiroshi Mizumoto, Anupam Kumar, Shiv K. Sarin, Hiroyuki Ijima, Masamichi Kamihira, Ashok Kumar, Alleviating liver failure conditions using an integrated hybrid cryogel based cellular bioreactor as a bioartificial liver support, Scientific Reports, DOI: 10.1038/srep40323, 7:40323, 1-11, 2017.01, Conventionally, some bioartificial liver devices are used with separate plasmapheresis unit to separate out plasma from whole blood and adsorbent column to detoxify plasma before it passes through a hepatocytes-laden bioreactor. We aim to develop a hybrid bioreactor that integrates the separate modules in one compact design improving the efficacy of the cryogel based bioreactor as a bioartificial liver support. A plasma separation membrane and an activated carbon cloth are placed over a HepG2-loaded cryogel scaffold in a three-chambered bioreactor design. This bioreactor is consequently connected extracorporeally to a rat model of acute liver failure for 3 h and major biochemical parameters studied. Bilirubin and aspartate transaminase showed a percentage decrease of 20–60% in the integrated bioreactor as opposed to 5–15% in the conventional setup. Urea and ammonia levels which showed negligible change in the conventional setup increase (40%) and decrease (18%), respectively in the integrated system. Also, an overall increase of 5% in human albumin in rat plasma indicated bioreactor functionality in terms of synthetic functions. These results were corroborated by offline evaluation of patient plasma. Hence, integrating the plasmapheresis and adsorbent units with the bioreactor module in one compact design improves the efficacy of the bioartificial liver device..
26. Nana Shirakigawa, Yuta Hara, Hiroyuki Ijima, Tissue-Engineered Bioreactors with Flow Channels Molded by Polypod Particles Advanced Biomedical Engineering, Advanced Biomedical Engineering, DOI:10.14326/abe.5.105, 5, 105-110, 2016.08, Good mass transfer and high cell density culture are required for bioreactors using animal cells. These criteria can be met by fabricating a tissue in the bioreactor. In the present study, polypod particles were prepared using agarose, carrageenan, calcium alginate, and hydroxyapatite. The particles were then packed into reactors, and the reactors were lled with enzymatically cross-linked gelatin. Reactors with ow channels were then obtained upon dissolution of the gel particles. Cell adhesion, growth, and expression of organ (liver) function in the reactor were subsequently examined. Experiment using CHO-K1 cells suggested that the cells adhered and grew on the internal surface of the ow channels. HepG2 cells inoculated into the reactor expressed liver-specic functions over the 3-day culture period examined. Thus, the current ndings demonstrate that the method developed can be applied to fabricate bioreactors to provide physiologically active substances and medical treatments for tissue engineering. Furthermore, this method was extended to the preparation of a hydroxyapatite-packed reactor by combining calcium alginate gel particles and hydroxyapatite. Therefore, this technique is expected to be applicable to both soft tissue models and hard tissue models such as bone..
27. Jingjia Ye, Nana Shirakigawa, Hiroyuki Ijima, Fetal liver cell-containing hybrid organoids improve cell viability and albumin production upon transplantation, Journal of Bioscience and Bioengineering, doi:10.1016/j.jbiosc.2015.11.006, 121, 6, 701-708, 2016.06.
28. Nana Shirakigawa, Tadamitsu Ideguchi, Kazuyuki Ichikawa, Takahisa Izumi, Michiko Higashi, Shizunari Yamamoto, Hiroyuki Ijima, Quantitative analysis of vascular structure in decellularized liver using 3D computed tomography, Advanced Biomedical Engineering, DOI:10.14326/abe.4.179, 4, 179-185, ABE No.15001 (Accepted, Aug 24/2015), 2015.12, Recently, decellularized liver (DC-liver) was developed as a scaffold for the creation of liver tissue because DC-liver has a vascular structure that is used for oxygen delivery. The structure was evaluated by the appearance of molded resin. In the present study, three-dimensional computed tomography was used to obtain images of the vascular structure. Imaging at the hepatic lobule level was achieved by coating the molded resin with contrast dye or gold. We defined indexes to evaluate blood vessel conformation and structure. The data for each index were obtained from the images. These data suggest that DC-liver has a fine vascular structure quantitatively similar to that of native liver. This method is valuable for the development of whole liver engineering..
29. Jingjia Ye, Nana Shirakigawa, Hiroyuki Ijima, Hybrid organoids consisting of extracellular matrix gel particles and hepatocytes for transplantation, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2015.01.004, 120, 2, 231-237, 2015.08, Hepatocyte transplantation is a potential therapy for treating various liver diseases. However, oxygen shortage and loss of hepatocyte function becomes a limitation following hepatocyte transplantation. To overcome this problem, we developed a hybrid organoid, consisting of growth factor (GF)-immobilizable gel particles combined with hepatocytes. Benefits of the hybrid organoid were evaluated in three groups: (1) hybrid organoid consisting of cells and GF-immobilizable gel particles (HG-C); (2) hybrid organoid consisting of cells and gel particles (G-C); and (3) cells suspended in collagen (C-C). We found liver specific functions of HG-C were maintained longer than in the other conditions during in vitro culture. Furthermore, after transplantation, HG-C was effective in maintaining viability of transplanted hepatocytes and promoting angiogenesis around the hepatocytes. In summary, transplantation of HG-C is a potential method for future liver tissue engineering..
30. Eric M. Jeffries, Shintaro Nakamura, Kee-Won Lee, Jimmy Clampffer, Hiroyuki Ijima, Yadong Wang, Micropatterning Electrospun Scaffolds to Create Intrinsic Vascular Networks, Macromolecular Bioscience, DOI: 10.1002/mabi.201400306, 14, 11, 1514-1520, 2014.11.
31. Hideyuki Mizumachi, Hiroyuki Ijima, Reliable Evaluation of Human Umbilical Vein Endothelial Cell Number by Water-soluble Tetrazolium Salts-8 Assay Using Charcoal/dextran-treated Fetal Bovine Serum , Advanced Biomedical Engineering, http://dx.doi.org/10.14326/abe.3.1, 3, 1-6, 2014.03, The objective of this study was to examine the validity of estimating cell number using the water-soluble tetrazolium salts-8 (WST-8) assay for normal cells. The changes in mitochondrial activity of human umbilical vein endothelial cells (HUVECs) cultured under various culture conditions were evaluated using this assay. We found that cell counting of HUVECs by the WST-8 assay was not accurate under certain culture conditions, because the mitochondrial activity per cell changed depending on culture duration and medium composition. When charcoal/dextran-treated fetal bovine serum (FBS) -supplemented medium was used in cultures, the mitochondrial activity per cell was similar both in the presence and in the absence of vascular endothelial growth factor (VEGF). Furthermore, the mitochondrial activity did not affect the proliferative activity of cells, because we observed VEGF-dependent proliferation of HUVECs in this medium. For precise evaluation of cell number using the WST-8 assay, it is important to consider the accuracy of the assay results. Thus, a reliable method of cell counting using WST-8 needs to be developed. .
32. Hideyuki Mizumachi, Hiroyuki Ijima, Measuring stability of vascular endothelial growth factor using an immobilization technique, Advanced Biomedical Engineering, http://dx.doi.org/10.14326/abe.2.130, 2, 130-136, 2013.12, Although immobilization of growth factors (GFs) on culture substrates has been investigated as a cell culture technique, quantification of the bioactive stability of immobilized GFs has not been studied in detail. We developed a system of measuring GF stability using heparin-immobilized collagen substrate, vascular endothelial growth factor (VEGF). and human umbilical vein endothelial cells (HUVECs). VEGF solution was added to a heparin-crosslinked substrate and immobilized on the substrate. HUVECs were cultured on the VEGF-immobilized substrate, and the mitochondrial activity of the cells was assessed. A calibration curve showing the relation between HUVEC mitochondrial activity and immobilized VEGF density was constructed. Next, immobilized VEGF and VEGF solution were pre-incubated at 37°C, and the pre-incubated VEGF was added to heparin-crosslinked substrate. HUVEC mitochondrial activity declined as the pre-incubation period increased. Density of active immobilized VEGF was derived from HUVEC mitochondrial activity using the calibration curve, and the effect of pre-incubation of VEGF at 37°C was demonstrated quantitatively. Even after culture for 16 days, immobilized VEGF in culture medium at 37°C retained 43%of the initial bioactivity. Immobilized VEGF retained activity better than VEGF solution for at least 12 days of pre-incubation. The present results indicate that immobilization improves the stability of VEGF. .
33. Shintaro Nakamura, Hiroyuki Ijima, Solubilized matrix derived from decellularized liver as a growth factor-immobilizable scaffold for hepatocyte culture, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2013.05.031 , 116, 6, 746-753, 2013.12, Tissue engineering requires growth factors, cells and a scaffold to permit effective tissue regeneration. This study focused on the development of a scaffold for liver tissue engineering, because the liver is a central organ for metabolism. We aimed to develop a scaffold to promote expression of liver-specific functions of hepatocytes, with a focus on immobilizing growth factors onto an organ-specific matrix for liver tissue regeneration. Solubilized extracellular matrix from decellularized liver (L-ECM) was obtained following Triton X-100 treatment and consisted of protein and polysaccharide. L-ECM was found to immobilize hepatocyte growth factor (HGF), even in the presence of albumin, with an efficiency of 75%. Additionally, the immobilized HGF on L-ECM film was stably remained in culture condition for 5 days. Immobilized HGF promoted hepatocyte migration, thus indicating that L-ECM-immobilized HGF maintained its native biological activity. Furthermore, L-ECM stimulated the expression of liver-specific functions, including albumin secretion, urea synthesis and ethoxyresorufin-O-deethylase activity, in primary rat hepatocytes cultured in growth factor-free medium. In summary, L-ECM has the potential to become an effective material in the field of regenerative medicine..
34. Nana Shirakigawa, Takayuki Takei, Hiroyuki Ijima, Base structure consisting of an endothelialized vascular-tree network and hepatocytes for whole liver engineering, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2013.05.020, 116, 6, 740-745, 2013.12, Reconstructed liver has been desired as a liver substitute for transplantation. However, reconstruction of a whole liver has not been achieved because construction of a vascular network at an organ scale is very difficult. We focused on decellularized liver (DC-liver) as an artificial scaffold for the construction of a hierarchical vascular network. In this study, we obtained DC-liver and the tubular network structure in which both portal vein and hepatic vein systems remained intact. Furthermore, endothelialization of the tubular structure in DC-liver was achieved, which prevented blood leakage from the tubular structure. In addition, hepatocytes suspended in a collagen sol were injected from the surroundings using a syringe as a suitable procedure for liver cell inoculation. In summary, we developed a base structure consisting of an endothelialized vascular-tree network and hepatocytes for whole liver engineering..
35. Nana Shirakigawa, Hiroyuki Ijima, Nucleus number in clusters of transplanted fetal liver cells increases by partial hepatectomy of recipient rats, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2012.11.015, 115, 5, 568-570, 2013.05, The growth of transplanted hepatocytes is required for the construction of tissue-engineered liver. In this study, cell-embedded hydrogel-filled polyurethane foam plates were subcutaneously transplanted into rat. A liver tissue-like structure was formed by transplanted fetal liver cells in 70% partial hepatectomy treated rat..
36. Shintaro Nakamura, Takafumi Kubo, Hiroyuki Ijima, Heparin-conjugated gelatin as a growth factor immobilization scaffold, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2012.11.011, 115, 5, 562-567, 2013.05, Tissue engineering requires growth factors, cells and a scaffold to permit effective tissue regeneration. This study aimed to develop a scaffold with a focus on immobilizing growth factors within gelatin. We focused on the extracellular matrix and developed a heparin-conjugated gelatin (Hep-gela). Conjugation was confirmed using the alcian blue assay and x-ray diffraction patterns. The mechanical strength and stability of the Hep-gela gel in protease solution were improved compared with collagen gel. Hep-gela was able to immobilize vascular endothelial growth factor (VEGF) even in the presence of albumin, with an efficiency of 54.2%. Immobilized VEGF promoted proliferation of human umbilical vein endothelial cells. Hep-gela-immobilized VEGF maintained its native biological activity. In summary, Hep-gela has the potential to become an effective material in the field of regenerative medicine..
37. Yung-Te Hou, Hiroyuki Ijima, Nana Shirakigawa, Takayuki Takei, Koei Kawakami, Development of growth factor-immobilizable material for hepatocyte transplantation, Biochemical Engineering Journal, http://dx.doi.org/10.1016/j.bej.2012.09.007, 69, 172-181, 2012.12, Growth factor (GF)-immobilizable materials were developed as a practical hepatocyte transplantation method for reconstructing a tissue-like structure in liver tissue engineering. Two GF-immobilizable scaffolds, namely single hepatocyte-embedded, heparin-immobilized, collagen-gel-filled polyurethane foam, and hepatocyte spheroid-embedded, heparin-immobilized, collagen-gel-filled polyurethane foam were developed by covalently incorporating heparin into collagen gel, using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide for hepatocyte transplantation. Seventy percent partial hepatectomy (PH) was performed at the same time after hepatocyte transplantation. Angiogenesis efficiency and viability of transplanted cells are discussed in terms of normalized hemoglobin content, nuclear density and histological observations after transplantation. In summary, the normalized hemoglobin content and viability of transplanted cells were higher in GF-immobilized scaffolds with PH pretreatment than in the other scaffolds with/without PH pretreatment. These materials have the potential for in vivo hepatocyte transplantation, as GFs released from remnant liver were easily incorporated into the heparin-immobilized collagen gel system. These GF–heparin complexes may promote the survival of embedded cells. Furthermore, the transplantation of spheroids promoted increased angiogenesis compared with hepatocytes, and resulted in sufficient vascularization for cell survival..
38. Nana Shirakigawa, Hiroyuki Ijima, and Takayuki Takei, Decellularized liver as a practical scaffold with a vascular network template for liver tissue engineering, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2012.05.022 , 114, 5, 546-551, 2012.11, The construction of a functional liver-tissue equivalent using tissue engineering is a very important goal because the liver is a central organ in the body. However, the construction of functional organ-scale liver tissue is impossible because it requires a high-density blood vessel network. In this study, we focused on decellularization technology to solve this problem. Decellularized liver tissue with a fine vascular tree network template was obtained using Triton X-100. The distance between each vascular structure was less than 1 mm. Endothelialization of the blood vessel network with human umbilical vein endothelial cells (HUVECs) was successfully performed without any leakage of HUVECs to the outside of the vessel structure. Furthermore, hepatocytes/spheroids could be located around the blood vessel structure. This study indicates that decellularized liver tissue is a potential scaffold for creating a practical liver tissue using tissue engineering technology..
39. Hiroyuki Ijima, Nana Shirakigawa, Hideyuki Mizumachi, Shintaro Nakamura, Hepatocyte embedded-functional gel-filled scaffold is effective for the construction of liver tissue-like structure, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 122, 2012.09.
40. N. Amimoto, T. Miyazawa, H. Tani, Hiroshi Mizumoto, Kohji Nakazawa, Hiroyuki Ijima, Kazumori Funatsu, Toshihisa Kajiwara, In vitro and ex vivo functional evaluation of a hollow fiber type bioartificial liver module immobilizing ES-derived hepatic cells, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 123, 2012.09.
41. Nana Shirakigawa, Hiroyuki Ijima, Endothelialized vascular tree in decellularized liver for liver tissue engineering, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 173, 2012.09.
42. Shintaro Nakamura, Hiroyuki Ijima, Solubilized matrix from decellulalized liver as a functional material for tissue engineering, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 173, 2012.09.
43. Nana Shirakigawa, Hiroyuki Ijima, Tadamitsu Ideguchi, Kazuyuki Ichikawa, Takahisa Izumi, Michiko Higashi, Shizunari Yamamoto, Yoshihiko Onizuka, Quantitative analysis of vascular tree structure in decellularized liver for tissue engineering, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 319, 2012.09.
44. Hiroyuki Ijima, Hideyuki Mizumachi, Development of evaluation system of growth factors on their stability and biological activity, Journal of Tissue Engineering and Regenerative Medicine, 6, Supplement 1, 323, 2012.09.
45. Takayuki Takei, Kaoru Ikeda, Hiroyuki Ijima, Masahiro Yoshida and Koei Kawakami, A comparison of sodium sulfate, sodium phosphate, and boric acid for preparation of immobilized Pseudomonas putida F1 in poly(vinyl alcohol) beads, Polymer Bulletin, 10.1007/s00289-012-0756-4, 69, 3, 363-373, 2012.06, Poly(vinyl alcohol) (PVA) gel beads crosslinked with sodium phosphate or boric acid have been widely utilized for microorganism immobilization. We previously utilized sodium sulfate to induce crosslinking of PVA for preparing immobilized yeast cells in PVA beads. In this study, we compared the toxicities of sodium sulfate and conventional crosslinkers (sodium phosphate and boric acid) toward Pseudomonas putida F1 (PpF1) and the performance of the corresponding immobilized PpF1 in PVA beads. The toxicity of sodium sulfate to PpF1 was lower than those of the conventional crosslinkers. PVA–sodium sulfate beads showed a higher gel fraction of PVA and a lower swelling ratio in water than PVA–sodium phosphate beads, which indicates that the former had higher stability. PpF1 immobilized in the PVA–sodium sulfate beads completely degraded the pollutant trichloroethylene (TCE) with an initial concentration (0.42 mg/l) within the most common range of TCE concentration found in contaminated field sites. .
46. Mizumoto H, Hayashi S, Matsumoto K, Ikeda K, Kusumi T, Inamori M, Nakazawa K, Ijima H, Funatsu K, Kajiwara T, Evaluation of a hybrid artificial liver module based on a spheroid culture system of embryonic stem cell-derived hepatic cells, Cell transplantation, 10.3727/096368911X605321, 21, 2, 421-418, 2012.02.
47. Takayuki TAKEI, Naoya KISHIHARA, Hiroyuki IJIMA, Koei KAWAKAMI, Fabrication of capillary-like network in matrix of water-soluble polymer using poly(methyl methacrylate) microfibers, Artificial cells, blood substitutes, and biotechnology, 40, 1-2, 66-69, in press, 2012.02.
48. Takayuki Takei, Hideki Nakahara, Hiroyuki Ijima, Koei Kawakami, Synthesis of a chitosan derivative soluble at neutral pH and gellable by freezing-thawing, and its application in wound care, Acta Biomaterialia, 8, 2, 686–693, 2012.02.
49. Takayuki Takei, Kotaro Sugihara, Hiroyuki Ijima, Koei Kawakami, In situ gellable sugar beet pectin via enzyme-catalyzed coupling reaction of feruloyl groups for biomedical applications, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2011.07.006, 112, 5, 491–494, 2011.11.
50. Yung-Te Hou, Hiroyuki Ijima, Takayuki Takei, Koei Kawakami, Growth factor/heparin-immobilized collagen gel system enhances viability of transplanted hepatocytes and induces angiogenesis, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2011.05.003, 112, 3, 265-272, 2011.09.
51. Amimoto N, Mizumoto H, Nakazawa K, Ijima H, Funatsu K, Kajiwara T, An evaluation of the utility of the hepatic differentiation method using hollow fiber/organoid culture for the development of a hybrid artificial liver device, Biochemical Engineering Journal, 10.1016/j.bej.2011.05.010, 56, 1-2, 69-74, 2011.09.
52. Amimoto N, Mizumoto H, Nakazawa K, Ijima H, Funatsu K, Kajiwara T, Hepatic Differentiation of Mouse Embryonic Stem Cells and Induced Pluripotent Stem Cells During Organoid Formation in Hollow Fibers, Tissue Eng Part A, 10.1089/ten.tea.2010.0689, 17, 15-16, 2071-2078, 2011 May 11. [Epub ahead of print], 2011.08.
53. Nana SHIRAKIGAWA, Takayuki TAKEI, Hiroyuki IJIMA, Koei KAWAKAMI, Optimization of Decellularized Conditions of Liver for the Development of Liver Tissue Engineering, Histology and Histopathology, 26, Supplement 1, 401, 2011.06.
54. Hiroyuki IJIMA, Nana SHIRAKIGAWA, Yung-Te HOU, Shintaro NAKAMURA, Takayuki TAKEI, Koei KAWAKAMI, Hepatocyte-embedded Functional Hydrogel-filled Scaffold System for Liver Tissue Engineering, Histology and Histopathology, 26, Supplement 1, 399, 2011.06.
55. Hiroyuki IJIMA, Shintaro NAKAMURA, Nana SHIRAKIGAWA, Hideyuki MIZUMACHI, Takayuki TAKEI, Koei KAWAKAMI, Growth factor-immobilized extracellular matrix for the culture of functional cells, Histology and Histopathology, 26, Supplement 1, 354, 2011.06.
56. Takayuki TAKEI, Kaoru IKEDA, Hiroyuki IJIMA, Koei KAWAKAMI, Fabrication of Poly(vinyl alcohol) Hydrogel Beads Crosslinked Using Sodium Sulfate for Microorganism Immobilization, Process Biochemistry, 46, 2, 566–571, 2011.02.
57. Takayuki TAKEI, Mitsunobu SATO, Hiroyuki IJIMA, Koei KAWAKAMI , In Situ Gellable Oxidized Citrus Pectin for Localized Delivery of Anti-Cancer Drugs and Prevention of Homotypic Cancer Cell Aggregation, Biomacromolecules, 11, 12, 3525–3530, 2010.12.
58. Hiroyuki Ijima, Yung-Te Hou, Takayuki Takei, Development of hepatocyte-embedded hydrogel-filled macroporous scaffold cultures using transglutaminase, Biochemical Engineering Journal, 10.1016/j.bej.2010.09.003, 52, 276-281, 2010.11.
59. Yung-Te Hou, Hiroyuki Ijima, Shunichi Matsumoto, Takafumi Kubo, Takayuki Takei, Shinji Sakai, and Koei Kawakami, Effect of a hepatocyte growth factor/heparin-immobilized collagen system on albumin synthesis and spheroid formation by hepatocytes, Journal of Bioscience and Bioengineering, doi:10.1016/j.jbiosc.2010.01.016, 110, 2, 208-216, 2010.08.
60. Takayuki TAKEI, Kaoru IKEDA, Hiroyuki IJIMA, Koei KAWAKAMI, Masahiro YOSHIDA, Yasuo HATATE, Preparation of polymeric microcapsules enclosing microbial cells by radical suspension polymerization via water-in-oil-in-water emulsion, Polymer Bulletin, 65, 3, 283-291, 2010.06.
61. Changjun MU, Shinji SAKAI, Hiroyuki IJIMA, Koei KAWAKAMI, Preparation of Cell-enclosing Microcapsules through Photopolymerization of Methacrylated Alginate Solution Triggered by Irradiation with Visible Light, Journal of Bioscience and Bioengineering, Vol.109, No.6, pp.618-621, 2010.06.
62. Hiroyuki Ijima, Practical and functional culture technologies for primary hepatocytes, Biochemical Engineering Journal, 10.1016/j.bej.2009.10.003, 48, 3, 332-336, Vol.48, No.3, pp.332-336, 2010.02.
63. Hiroyuki Ijima, Ryohei Ogata, Yusuke Murasawa, Pi-Chao Wang, Albumin production activity of primary rat hepatocytes is improved on type V collagen, Journal of Bioscience and Bioengineering, 10.1016/j.jbiosc.2009.07.017, 109, 2, 179-181, Vol.109, No.2, pp.179-181, 2010.02.
64. Hiroyuki Ijima, Hiroshi Mizumoto, Kohji Nakazawa, Toshihisa Kajiwara, Taku Matsushita, Kazumori Funatsu, Hepatocyte growth factor and epidermal growth factor promote spheroid formation in polyurethane foam/hepatocyte culture and improve expression and maintenance of albumin production, Biochemical Engineering Journal, 10.1016/j.bej.2009.06.012, 47, 1-3, 19-26, Vol.47, No.1-3, pp.19-26, 2009.12.
65. Hiroyuki Ijima, Takafumi Kubo, Yung-Te Hou, Primary rat hepatocytes form spheroids on hepatocyte growth factor/heparin-immobilized collagen film and maintain high albumin production, Biochemical Engineering Journal, 10.1016/j.bej.2009.05.017, 46, 2, 227-233, Vol.46, No.2, pp.227-233, 2009.10.
66. Akira Ito, Hideaki Jitsunobu, Yoshinori Kawabe, Hiroyuki Ijima, Masamichi Kamihira, Magnetic Separation of Cells in Coculture Systems Using Magnetite Cationic Liposomes, Tissue Engineering Part C: Methods, Vol.15, No.3, pp.413-423, 2009.09.
67. Hiroyuki Ijima, Yung-Te Hou, Takafumi Kubo, Ryohei Ogata, Nana Shirakigawa, Takayuki Takei, Shinji Sakai, KOEI KAWAKAMI, Basic Study for Liver Tissue Engineering by Developing Hepatocytes-Embedded Functional Hydrogel-Filled Scaffold Culture, Tissue Engineering and Regenerative Medicine, 6, Supplement 1, S32, 2009.09.
68. Hiroshi Mizumoto, S. HAYASHI, K. IKEDA, Kohji NAKAZAWA, Hiroyuki Ijima, Kazumori Funatsu, Toshihisa Kajiwara, Evaluation of a Hybrid Artificial Liver Module Based on a Spheroid Culture System of ES Cell-derived Hepatic Cells, Tissue Engineering and Regenerative Medicine, 6, Supplement 1, S116, 2009.09.
69. Hiroyuki Ijima, Yasuo Kakeya, Toru Yokonuma, Yung-Te Hou, Takayuki Takei, Composition of culture medium is more important than co-culture with hepatic non-parenchymal cells in albumin production activity of primary rat hepatocytes, and the effect was enhanced by hepatocytes spheroid culture in collagen gel, Biochemical Engineering Journal, 10.1016/j.bej.2009.04.002, 45, 3, 226-231, Vol.45, No.3, pp.226-231, 2009.08.
70. Tomoaki Kusumi, Kazuhisa Ishihara, Hiroshi Mizumoto, Kohji Nakazawa, Hiroyuki Ijima, Kazumori Funatsu, Toshihisa Kajiwara, Evaluation of a bioreactor with stacked sheet shaped organoids of primary hepatocytes, Journal of Bioscience and Bioengineering, Vol.107, No.5, pp.552–555, 2009, 2009.05.
71. Hiroyuki Ijima, Yasuo Kakeya, Takahiro Ogata, Takanori Sakai, Development of a practical small-scale circulation bioreactor and application to a drug metabolism simulator, Biochemical Engineering Journal, 10.1016/j.bej.2008.12.015, 44, 2-3, 292-296, Vol.44, No.2-3, pp.292-296, 2009.05.
72. Akira Ito, Takehiko Kiyohara, Yoshinori Kawabe, Hiroyuki Ijima, Masamichi Kamihira, Enhancement of Cell Function through Heterotypic Cell-Cell Interactions Using E-Cadherin-Expressing NIH3T3 Cells, Journal of Bioscience and Bioengineering, Vol.105, No.6, pp.679-682, 2008.06.
73. Hiroyuki IJIMA, Yasuo KAKEYA, Monolayer culture of primary rat hepatocytes on an Arg-Gly-Asp (RGD)-immobilized polystyrene dish express liver-specific functions of albumin production and p-acetamidophenol metabolism the same as for spheroid culture, Biochemical Engineering Journal, 10.1016/j.bej.2008.01.009, 40, 2, 387-391, Vol.40, No.2, pp.387-391, 2008.06.
74. Hiroshi MIZUMOTO, Kazuhisa ISHIHARA, Kohji NAKAZAWA, Hiroyuki IJIMA, Kazumori FUNATSU, Toshihisa KAJIWARA, A new culture technique for hepatocyte organoid formation and long-term maintenance of liver-specific functions, Tissue Engineering Part C: Method, 14, 2, 387-391, 2008.06.
75. K. MATSUMOTO, H. MIZUMOTO, K. NAKAZAWA, H. IJIMA, K. FUNATSU, T. KAJIWARA, Hepatic differentiation of mouse embrionic stem cells in a three-dimensional culture system using polyurethane foam, Journal of Bioscience and Bioengineering, Vol.105, No.4, pp.350-354, 2008, 2008.04.
76. H. Mizumoto, K. Aoki, K. Nakazawa, H. Ijima, K. Funatsu, and T. Kajiwara, Hepatic Differentiation of Embryonic Stem Cells in HF/Organoid Culture, Transplantation Proceedings, Vol.40, pp.611-613, 2008, 2008.02.
77. K. Matsumoto, H. Mizumoto, K. Nakazawa, H. Ijima, K. Funatsu, and T. Kajiwara, Hepatic Differentiation of Mouse Embryonic Stem Cells in a Bioreactor Using Polyurethane/Spheroid Culture, Transplantation Proceedings, Vol.40, pp.614-616, 2008, 2008.02.
78. Hiroyuki IJIMA, Takeshi MATSUO, Koei KAWAKAMI, The mixed co-culture effect of primary rat hepatocytes and bone marrow cells is caused by soluble factors derived from bone marrow cells, Journal of Bioscience and Bioengineering, 105, 3, 226-231, Vol.105, No.3, pp.226-231, 2008.03.
79. Takayuki TAKEI, Shinsuke YAMAGUCHI, Shinji SAKAI, Hiroyuki IJIMA, Koei KAWAKAMI, Novel Technique to Fabricate Double-Layered Tubular Construct Composed of Two Vascular Cell Types in Collagen Gel as Template of Three-dimensional Tissue, Journal of Bioscience and Bioengineering, Vol.105, No.5, pp.435-438, 2007.11.
80. Hiroyuki Ijima, Toru Yokonuma, Yasuo Kakeya, Shinji Sakai, Koei Kawakami, Expression and maintenance of liver specific function of primary rat heptaocytes co-cultured with hepatic non-parenchymal cells in collagen gel, Proceedings of TERMIS-NA 2007 Conference and Exposition, No.1218, 2007.07.
81. Hiroyuki Ijima, Toru Yokonuma, Shinji Sakai, Koei Kawakami, Spheroid formation and expression fo liver specific function of primary rat hepatocytes co-cultured with hepatic non-parenchymal cells, ASAIO journal, Vol.53, No.2, p.7A, 2007.03.
82. Takayuki TAKEI, Shinji SAKAI, Hiroyuki IJIMA, Koei KAWAKAMI, Expression of a Liver-Specific Function by a Hepatoblastoma Cell Line Cocultured with Three-Dimensional Endothelialized Tubes in Collagen Gels, Journal of Bioscience and Bioengineering, Vol.103, No.2, pp.200-202, 2007.02.
83. Takayuki TAKEI, Shinji SAKAI, Toru YOKONUMA, Hiroyuki IJIMA, Koei KAWAKAMI, Fabrication of Artificial Endothelialized Tubes with Predetermined Three-dimensional Configuration from Flexible Cell-enclosing Alginate Fibers, Biotechnology Progress, Vol.23, No.1, pp.182-186, 2007.02.
84. Hiroyuki IJIMA, Shohei KURODA, Koei KAWAKAMI, Degoxin transport by renal proximal tubule cells is enhanced on adhesive synthetic RGD peptide, The International Journal of Artificial Organs, Vol.30, No.1, pp.25-33, 2007.01.
85. Takayuki TAKEI, Shinji SAKAI, Hiroyuki IJIMA, Koei KAWAKAMI, Development of Mammalian Cell-enclosing Calcium-alginate Hydrogel Fibers in a Coflowing-stream, Biotechnology Journal, Vol.1, No.9, 1014-1017, 2006.09.
86. Takayuki TAKEI, Shinji SAKAI, Tsutomu ONO, Hiroyuki IJIMA, Koei KAWAKAMI, Fabrication of Endothelizlized Tube in Collagen Gel as Starting Point for Self-developing Capillary-like Network to Construct Three-dimensional Organs in Vitro, Biotechnology and Bioengineering, Vol.95, No.1, pp.1-7, 2006, 2006.09.
87. Sunao MURAKAMI, Tsutomu ONO, Shinji SAKAI, Hiroyuki IJIMA, Koei KAWAKAMI, Effect of Diglucosamine on the Entrapment of Protein into Liposomes, Journal of Liposome Research, Vol.16, No.2, pp.103-112, 2006.05.
88. Shinji Sakai, Kenji Kawabata, Shinji Tanaka, Norifumi Harimoto, Ichiro Hashimoto, Changjun Mu, Brian Salmons, Hiroyuki Ijima, Koei Kawakami, Subsieve-size agarose capsules enclosing ifosfamide-activating cells: a strategy toward chemotherapeutic targeting to tumors, Molecular Cancer Therapeutics, 10.1158/1535-7163.MCT-05-0227, 4, 11, 1786-1790, Vol.4, pp.1786-1790, 2005.11.
89. Takayuki Takei, Hiroyuki Ijima, Shinji Sakai, Tsutomu Ono, Koei Kawakami, Enhanced angiogenesis in bFGF-containing scaffold promoted viability of enclosed hepatocytes and maintained hepatospecific glycogen storage capacity, Journal of Chemical Engineering of Japan, 10.1252/jcej.38.913, 38, 11, 913-917, Vol.38, No.11, pp.913-917, 2005, 2005.11.
90. Hiroyuki Ijima, Sunao Murakami, Takeshi Matsuo, Takayuki Takei, Tsutomu Ono, Koei Kawakamii, Enhancement of liver specific functions of primary rat hepatocytes co-cultured with bone marrow cells on tissue culture treated polystyrene surfaces, Journal of Artificial Organs, Vol.8, No.2, pp.104-109, 2005.08.
91. Shinji Sakai, Hiroki Masuhara, Yusuke Yamada, Tsutomu Ono, Hiroyuki Ijima, Koei Kawakami, Transition of mechanical property of porous alginate scaffold with cells during culture period, Journal of Bioscience and Bioengineering, 10.1263/jbb.100.127, 100, 1, 127-129, Vol.100, No.1, pp.127-129, 2005.07.
92. Hiroyuki Ijima, Koei Kawakami, Promote a monolayer formation and highly express the ammonia metabolism of primary rat hepatocyte on a RGD-containing peptide coated polystyrene dish, Journal of Bioscience and Bioengineering, Vol.100, No.1, pp.62-66, 2005.07.
93. Shinji Sakai, Kenji Kawabata, Tsutomu Ono, Hiroyuki Ijima, Koei Kawakami, Higher viscous solution induces smaller droplets for cell-enclosing capsules ina co-flowing stream, Biotechnology Progress, 10.1021/bp049600i, 21, 3, 994-997, Vol.21, pp.994-997, 2005, 2005.06.
94. Hiroyuki IJIMA, Takeshi MATSUO and Koei KAWAKAMI, Development of a Functional Culture Medium for Primary Rat Hepatocytes, Proceedings of 7th Asia-Pacific Biochemical Engineering Conference, 2005, 2005.05.
95. Sunao MURAKAMI, Shinji SAKAI, Tsutomu ONO, Hiroyuki IJIMA and Koei KAWAKAMI, Preparation of Chitosan Oligosaccharide-Phospholipid Complex, Proceedings of 7th Asia-Pacific Biochemical Engineering Conference, 2005, 2005.05.
96. Shinji Sakai, Kenji Kawabata, Tsutomu Ono, Hiroyuki Ijima, Koei Kawami, Development of mammalian cell-enclosing subsieve-size agarose capsules (<100um) for cell therapy, Biomaterials, 10.1016/j.biomaterials.2004.11.043, 26, 23, 4786-4792, Vol.26, pp.4786-4792, 2005.01.
97. Koei Kawakami, Yoshihide Sera, Shinji Sakai, Tsutomu Ono, Hiroyuki Ijima, Development and Characterization of a Silica Monolith Immobilized Enzyme Micro-bioreactor, Industrial & Engineering Chemistry Research, 10.1021/ie049354f, 44, 1, 236-240, Vol.44, No.1, pp.236-240, 2005.01.
98. Tsutomu Ono, Mai Nagatomo, Tomoaki Nagao, Hiroyuki Ijima, Koei Kawakami, Non-aggregating refolding of Ribonclease A using reverse micellar dialysis, Biotechnology and Bioengineering, 10.1002/bit.20329, 89, 3, 290-295, Vol.89, No.3, pp.290-295, 2005.02.
99. H. Ijima, S. Kuroda, K. Kawakami, Digoxin transport by renal proximal tubule cells is enhanced on adhesive synthetic RGD peptide, Proceedings of 10th Asian Pacific Confederation of Chemical Engineering (APCChE) Congress, 2004.10.
100. T. Takei, H. Ijima, S. Sakai, T. Ono, K. Kawakami, Development of bFGF sustained-release bioabsorbable sponge and enhancement of angiogenesis in it, Proceedings of 10th Asian Pacific Confederation of Chemical Engineering (APCChE) Congress, 2004.10.
101. M. Morita, T. Ono, S. Sakai, H.Ijima, K. Kawakami, Development of DNA-containing nano scale vesicle by reverse micelles, Proceedings of 10th Asian Pacific Confederation of Chemical Engineering (APCChE) Congress, 2004.10.
102. S. Sakai, K. Kawabata, T. Ono, H. Ijima, K. Kawakami, Preparation of Mammalian Cell-Enclosing Subsieve-Sized Capsules (<100 um) in a Coflowing Stream, Proceedings of 10th Asian Pacific Confederation of Chemical Engineering (APCChE) Congress, 2004.10.
103. H. Ijima, T. Takei, K. Kawakami, Development of basic fibroblast growth factor sustained-releasable acidic gelatin-coated porous scaffold and its application to tissue engineering, ASAIO Journal, Vol.50, No.2, p.159, 2004.03.
104. H. Ijima, M. Nakashima, S. Furuta, T. Ono, K. Kawakami, Hydrothermal synthesis of porous hydroxyapatite plates from gypsum: Use as an animal cell culture substratum, Journal of Chemical Engineering of Japan, 10.1252/jcej.37.531, 37, 4, 531-535, Vol.37, No.4, pp.531-535, 2004.04.
105. S. Sakai, K. Kawabata, T. Ono, H. Ijima, K. Kawakami, Preparetion of mammalian cell-enclosing subsieve-sized capsules (<100um) in a coflowing stream, Biotechnology and Bioengineering, 10.1002/bit.20006, 86, 2, 168-173, Vol.86, No.2, pp.168-173, 2004.04.
106. S. Murakami, H. Ijima, T. Ono, K. Kawakami, Development of co-culture system of hepatocytes with bone marrow cells for expression and maintenance of hepatic functions, The International Journal of Artificial Organs, 27, 2, 118-126, Vol.27, No.2, pp.118-126, 2004.02.
107. H. Ijima, Y. Wang, R. Langer, Spheroid formation and expression of liver specific function of primary rat hepatocytes co-cultured with bone marrow cells, Biochemical Engineering Journal, 10.1016/j.bej.2003.09.014, 20, 2-3, 223-228, Vol.20, No.2-3, pp.223-228, 2004.08.
108. H. Ijima, T. Ohchi, T. Ono, K. Kawakami, Hydroxyapatite for use as an animal cell culture substratum obtained by an alternate soaking process, Biochemical Engineering Journal, 10.1016/j.bej.2003.07.004, 20, 2-3, 155-161, Vol.20, No.2-3, pp.155-161, 2004.08.
109. S. Sakai, T. Ono, H. Ijima, K. Kawakami, MIN6 cells-enclosing aminopropyl-silicate membrane templated by alginate gels differences in guluronic acid content, International Journal of Pharmaceutics, 10.1016/j.ijpharm.2003.10.014, 270, 1-2, 65-73, Vol.270, pp.65-73, 2004.02.
110. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Proliferation and insulin secretion function of mouse insulinoma cells encapsulated in alginate/sol-gel synthesized aminopropyl-silicate/alginate microcapsule, Journal of Sol-Gel Science and Technology, 10.1023/A:1026045503586, 28, 2, 267-272, Vol.28, pp.267-272, 2003.09.
111. Y. Yamashita, M. Shimada, E. Tsujita, K. Shirabe, H. Ijima, K. Nakazawa, R. Sakiyama, J. Fukuda, K. Funatsu, K. Sugimachi, Efficacy of a larger version of the hybrid artificial liver support system using a polyurethane foam/spheroid packed-bed module in a warm ischemic liver failure pig model for preclinical experiment, Cell Transplantation, 12, 2, 101-107, Vol.12, No.2, pp.101-107, 2003.01.
112. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Modification of porous aminopropyl-silicate microcappsule membrane by electrically-bonded external anionic polymers, J. Biomater. Sci. Polymer Edn., 10.1163/156856203322274905, 14, 7, 643-652, Vol.14, No.7, pp.643-652, 2003.01.
113. J. Fukuda, K. Okamura, K. Nakazawa, H. Ijima, Y. Yamashita, M. Shimada, K. Shirabe, E. Tsujita, K. Sugimachi, K. Funatsu, Efficacy of a polyurethane foam/spheroid artificial liver by using human hepatoblastoma cell line (Hep G2), Cell Transplantation, 10.3727/000000003783985151, 12, 1, 51-58, Vol.12, No.1, pp.51-58, 2003.01.
114. K. Kawakami, Y. Matsui, T. Ono, H. Ijima, Enhancement of protease activity in transesterification of glycidol with vinyl n-butyrate by entrapment into alkyl-substituted silicates and pretreatment with a substrate, Biocatalysis and Biotransformation, 10.1080/1024242031000087628, 21, 1, 49-52, Vol.21, No.1, pp.49-52, 2003.02.
115. R. Sakiyama, K. Nakazawa, H. Ijima, H. Mizumoto, T. Kajiwara, M. Ito, H. Ishibashi, K. Funatsu, Recovery of rats with fulminant hepatic failure by using a hybrid artificial liver support system with polyurethane foam/rat hepatocyte spheroid, International Journal of Artificial Organs, 25, 12, 1144-1152, Vol.25, No.12, pp.1144-1152, 2002.12.
116. S. Sakai, T. Ono, H. Ijima, K. Kawakami, In vitro and in vivo evaluation of alginate/sol-gel synthesized aminopropyl-silicate/alginate membrane for bioartificial pancreas, Biomaterials, 10.1016/S0142-9612(02)00159-X, 23, 21, 4177-4183, Vol.23, No.21, pp.4177-4183, 2002.11.
117. Y. Yamashita, M. Shimada, E. Tsujita, K. Shirabe, H. Ijima, K. Nakazawa, R. Sakiyama, J. Fukuda, K. Funatsu, K. Sugimachi, High metabolic function of primary human and porcine hepatocytes in a polyurethane foam/spheroid culture system in plasma from patients with fulminant hepatic failure, Cell Transplantation, 11, 4, 379-384, Vol.11, No.4, 379-384, 2002.01.
118. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Permeability of alginate/sol-gel synthesized aminopropyl-silicate/alginate membrane templated by calcium-alginate gel, Journal of Membrane Science, 10.1016/S0376-7388(02)00093-5, 205, 1-2, 183-189, Vol.205, No.1-2, pp.183-189, 2002.08.
119. Shinji Sakai, Tsutomu Ono, Hiroyuki Ijima, Koei Kawakami, Permeability of a sol-gel synthesized aminopropyl-silicate-titanate hybrid membrane for the microcapsule-shaped bioartificial pancreas, Journal of Artificial Organs, Vol.5, pp.54-59, 2002, 2002.01.
120. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Aminopropyl-silicate membrane for microcapsule-shaped bioartificial organs: control of molecular permeability, Journal of Membrane Science, 10.1016/S0376-7388(01)00731-1, 202, 1-2, 73-80, Vol.202, No.1-2, pp.73-80, 2002.06.
121. S. Furukawa, T. Ono, H. Ijima, K. Kawakami, Effect of imprinting sol-gel immobilized lipase with chiral template substrates in esterification of (R)-(+)- and (S)-(-)-glycidol, Journal of Molecular Catalysis B-Enzymatic, 10.1016/S1381-1177(01)00076-5, 17, 1, 23-28, Vol.17, No.1, pp.23-28, 2002.03.
122. Y. Yamashita, M. Shimada, H. Ijima, K. Nakazawa, K. Funatsu, Hybrid artificial liver support system, Surgery, 10.1067/msy.2002.120118, 131, 1, S334-S340, Vol.131, No.1, S334-S340, 2002.01.
123. K. Nakazawa, H. Ijima, J. Fukuda, R. Sakiyama, Y. Yamashita, M. Shimada, K. Shirabe, E. Tsujita, K. Sugimachi, K. Funatsu, Development of a hybrid artificial liver using polyurethane foam/hepatocyte spheroid culture in a preclinical pig experiment, The International Journal of Artificial Organs, 25, 1, 51-60, Vol.25, No.1, pp.51-60, 2002.01.
124. S. Furukawa, T. Ono, H. Ijima, K. Kawakami, Activation of protease by sol-gel entrapment into organically modified hybrid silicates, Biotechnology letters, 10.1023/A:1013876313806, 24, 1, 13-16, Vol.24, No.1, pp.13-16, 2002.01.
125. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Newly developed aminopropyl-silicate immunoisolation membrane for a microcapsule-shaped bioartificial pancreas, Annals of the New York Academy of Science, 944, 277-283, Vol.944, pp.277-283, 2001.01.
126. H. Ijima, A. Noguchi, T. Katsuno, T. Ono, K. Nakazawa, K. Funatsu, Evaluating the performance of a hybrid artificial liver support system with a recoverable hepatic failure rat model, Annals of the New York Academy of Science, 944, 344-349, Vol.944, pp.344-349, 2001.01.
127. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Synthesis and transport characterization of alginate/aminopropylsilicate/alginate microcapsule: application to bioartificial pancreas, Biomaterials, 10.1016/S0142-9612(01)00016-3, 22, 21, 2827-2834, Vol.22, No.21, pp.2827-2834, 2001.11.
128. J. Fukuda, R. Sakiyama, K. Nakazawa, H. Ijima, Y. Yamashita, M. Shimada, K. Shirabe, E. Tsujita, K. Sugimachi, K. Funatsu, Mass preparation of primary porcine hepatocytes and the design of a hybrid artificial liver module using spheroid culture for a clinical trial, The International Journal of Artificial Organs, 24, 11, 799-806, Vol.24, No.11, pp.799-806, 2001.11.
129. J. Fukuda, K. Okamura, R. Sakiyama, K. Nakazawa, H. Ijima, Y. Yamashita, M. Shimada, K. Shirabe, S. Tanaka, E. Tsujita, K. Sugimachi, K. Funatsu, Development of a hybrid artificial liver support system for a clinical trial, Hepatology, 34, 4, 304A-304A, Vol.34, No.4, p.304A, 2001.10.
130. K. Nakazawa, H. Mizumoto, K. Ishihara, H. Ijima, K. Funatsu, Establishment of novel hepatocyte organoid culture and its application to development of hybrid artificial liver module, Hepatology, 34, 4, 662A-662A, Vol.34, No.4, p.662A, 2001.10.
131. S. Furukawa, T. Ono, H. Ijima, K. Kawakami, Enhancement of activity of sol-gel immobilized lipase in organic media by pretreatment with substrate analogues, Journal of Molecular Catalysis B-Enzymatic, 10.1016/S1381-1177(01)00007-8, 15, 1-3, 65-70, Vol.15, No.1-3, pp.65-70, 2001.09.
132. Y. Yamashita, M. Shimada, E. Tsujita, S. Tanaka, H. Ijima, K. Nakazawa, R. Sakiyama, J. Fukuda, T. Ueda, K. Funatsu, K. Sugimachi, Polyurethane foam/spheroid culture system using human hepatoblastoma cell line (Hep G2) as a possible new hybrid artificial liver, Cell Transplantation, 10, 8, 717-722, Vol.10, No.8, pp.717-722, 2001.01.
133. Control of transport characteristic of membrane by multi-layering of polyelectrolyte complex toward microcapsule-shaped bioartificial pancreas.
134. K. Funatsu, H. Ijima, K. Nakazawa, Y. Yamashita, M. Shimada, K. Sugimachi, Hybrid artificial liver using hepatocyte organoid culture, Artificial Organs, 10.1046/j.1525-1594.2001.025003194.x, 25, 3, 194-200, Vol.25, No.3, pp.194-200, 2001.03.
135. Y. Yamashita, M. Shimada, E. Tsujita, T. Rikimaru, H. Ijima, K. Nakazawa, R. Sakiyama, J. Fukuda, K. Funatsu, K. Sugimachi, The efficacy of nafamostat mesilate on the performance of a hybrid artificial liver using a polyurethane foam/prcine hepatocyte spheroid culture system in hyman plasma, The International Journal of Artificial Organs, 24, 1, 34-40, Vol.24, No.1, pp.34-40, 2001.01.
136. H. Ijima, K. Nakazawa, M. Kaneko, J. Fukuda, M. Shimada, Y. Yamashita, T. Gion, K. Shirabe, K. Sugimachi and K. Funatsu, Development of a hybrid artificial liver support system and preclinical animal experiment, Journal of Artificial Organs, Vol.3, No.2, pp.112-116, 2000.12.
137. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Fabrication and evaluation of sol-gel synthesized microcapsule as a bioartificial pancreas, Proceedings of the 5th Kyushu/Pusan-Kyoungnam & 4th Kyushu/Taipei Chemical Engineering Conference, pp.90-91, 2000.12.
138. T. Ono, G. Kojima, H. Ijima, K. Kawakami, Enzyme immobilization in nanosilica particles prepared by reversed micelles, Proceedings ofYABEC 2000 Symposium, pp.27, 2000.11.
139. Catalytic capabilities of lipase immobilized into organically modified silicates by sol-gel method.
140. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Control of molecular weight cut-off for immunoisolation by multilayering glycol chitosan-alginate polyion complex on alginate-based microcapsule, Journal of Microencapsulation, 17, 6, 691-699, Vol.17, NO.6, pp.691-699, 2000.11.
141. Y. Yamashita, M. Shimada, T. Gion, H. Hasegawa, H. Ijima, K. Nakazawa, R. Sakiyama, J. Fukuda, K. Funatsu, K. Sugimachi, Hybrid artificial liver using a polyurethane foam packed-bed culture system, New Aspects of High Technology in Medicine (Proceedings of the World Congress of High-Tech Medicine), 313-316, pp.313-316, 2000.10.
142. G. Kojima, T. Ono, H. Ijima, K. Kawakami, Preparation of enzyme-entrapped nanosilica particles by using reversed micelles, Proceedings of the 13th Symposium on Chemical Engineering, Kyushu-Taejon/Chungnam, Vol.13, pp.395-396, 2000.10.
143. T. Ohchi, K. Nakao, T. Ono, H. Ijima, K. Kawakami, The formation and evaluation of a hydroxyapatite as an animal cell culture substratum, Proceedings of the 13th Symposium on Chemical Engineering, Kyushu-Taejon/Chungnam, Vol.13, pp.299-300, 2000.10.
144. S. Shimono, F. Abe, T. Ono, H. Ijima, K. Kawakami, Effect of reactivation conditions on stability of immobilized pseudomonas putida KF715-D6 in biodegradation of trichloroethylene, Proceedings of the 13th Symposium on Chemical Engineering, Kyushu-Taejon/Chungnam, Vol.13, pp.295-296, 2000.10.
145. K. Yamamoto, T. Ono, H. Ijima, K. Kawakami, Cell-free protein synthesis using template DNA in reversed micelles, Proceedings of the 13th Symposium on Chemical Engineering, Kyushu-Taejon/Chungnam, Vol.13, pp.275-276, 2000.10.
146. H. Ijima, K. Nakazawa, S. Koyama, M. Kaneko, T. Matsushita, T. Gion, K. Shirabe, M. Shimada, K. Takenaka, K. Sugimachi and K. Funatsu, Conditions required for a hybrid artificial liver support system using PUF/hepatocyte-spheroid packed-bed module and it's use in dogs with liver failure, The International Journal of Artificial Organs, 23, 7, 446-453, Vol.23, No.7, pp.446-453, 2000.07.
147. H. Ijima, K. Nakazawa, S. Koyama, M. Kaneko, T. Matsushita, T. Gion, K. Shirabe, M. Shimada, K. Takenaka, K. Sugimachi and K. Funatsu, Development of a hybrid artificial liver using a polyurethane foam/hepatocyte-spheroid packed-bed module, The International Journal of Artificial Organs, 23, 6, 389-397, Vol.23, No.6, pp.389-397, 2000.06.
148. K. Nakazawa, H. Mizumoto, M. Kaneko, H. Ijima, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, K. Funatsu, Formation of porcine hepatocyte spheroid multicellular aggregates (spheroid) and analysis of drug metabolic functions, Cytotechnology, 10.1023/A:1008040726236, 31, 1-2, 61-68, Vol.31, No.1-2, pp.61-68, 1999.01.
149. H. Mizumoto, M. Hayakami, K. Nakazawa, H. Ijima, K. Funatsu, Formation of cylindrical multicellular aggregate (cylindroid) and expression of liver specifuc functions of primary rat hepatocytes, Cytotechnology, 10.1023/A:1008092710307, 31, 1-2, 69-75, Vol.31, No.1-2, pp.69-75, 1999.01.
150. S. Sakai, T. Ono, H. Ijima, K. Kawakami, Transport characterization of barium alginate gel beads multilayered with glycol chitosan-alginate polyion complex for bioartificial pancreas, Proceedings of APBioChEC'99, 1999.11.
151. S. Furukawa, T. Ono, H. Ijima, K. Kawakami, Esterification characteristics of lipase immobilized into organic-inorganic hybrid silicates, Proceedings of APBioChEC'99, 1999.11.
152. S. Shimono, N. Nakamura, T. Ono, H. Ijima, K. Kawakami, A. Suyama, K. Furukawa, Degradation of trichloroethylene by immobilized whole cells of recombinant pseudomonas putida KF715-D6, Proceedings of APBioChEC'99, 1999.11.
153. A. Noguchi, T. Katsuno, T. Ono, H. Ijima, K. Nakazawa, K. Funatsu, Study of an artificial liver support system with recoverable hepatic failure rat model, Proceedings of the 12th Symposium on Chemical Engineering, Taejon/Chungnam-Kyushu, Vol.12, pp.341-342, 1999.10.
154. S. Furukawa, T. Ono, H. Ijima, K. Kawakami, A kinetic study of menthol esterification with butyric acid catalyzed by organic-inorganic hybrid gel-immobilized lipase in organic media, Proceedings of the 12th Symposium on Chemical Engineering, Taejon/Chungnam-Kyushu, Vol.12, pp.209-210, 1999.10.
155. H. Hasegawa, M. Shimada, T. Gion, H. Ijima, K. Nakazawa, K. Funatsu, K. Sugimachi, Modulation of immunologic reactions between cultured porcine hepatocytes and human sera, ASAIO Journal, 10.1097/00002480-199909000-00005, 45, 5, 392-396, Vol.45, No.5, pp.392-396, 1999.09.
156. K. Nakazawa, H. Ijima, M. Kaneko, J. Fukuda, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, K. Funatsu, Development of a hybrid artificial liver support system and its application to hepatic failure animals, Tissue Engineering for Therapeutic Use 3, 1175, 43-52, pp.43-52, 1999.09.
157. K. Nakazawa, H. Ijima, M. Kaneko, J. Fukuda, M. Shimada, T. Utsunomiya, T. Gion, Y. Yamashita, K. Sugimachi, K. Funatsu, Spheroid formation of primary hepatocytes using polyurethane foam and maintenance of liver-specific functions, ASAIO Journal, Vol.45, No.2, p.202, 1999.05.
158. H. Ijima, K. Nakazawa, M. Kaneko, T. Katsuno, J. Fukuda, M. Shimada, T. Utsunomiya, T. Gion, Y. Yamashita, K. Sugimachi and K. Funatsu, Preclinical animal experiment of a hybrid artificial liver, ASAIO Journal, Vol.45, No.2, pp.201, 1999.05.
159. M. Kaneko, T. Ito, K. Nakazawa, H. Ijima, T. Matsushita, T. Gion, M. Shimada, K. Shirabe, H. Hasegawa, K. Takenaka, K. Sugimachi, K. Funatsu, Development of a hybrid artificial liver support system with porcine hepatocyte spheroids for preclinical use, Animal Cell Technology: Basic & Spplied Aspects, 277-281, Vol.10, pp.277-281, 1999.05.
160. H. Mizumoto, M. Kaneko, K. Nakazawa, H. Ijima, T. Matsushita, K. Funatsu, Formation of cylindrical multicellular aggregate (Cylindroid) of rat hepatocytes on pressed sheet of polyurethane foam, Animal Cell Technology: Basic & Spplied Aspects, 229-233, Vol.10, pp.229-233, 1999.05.
161. T. Gion, M. Shimada, K. Shirabe, K. Nakazawa, H. Ijima, T. Matsushita, K. Funatsu, K. Sugimachi, Evaluation of a hybrid artificial liver using a polyurethane foam packed-bed culture system in dogs, Journal of Surgical Research, 10.1006/jsre.1998.5540, 82, 2, 131-136, Vol.82, No.2, pp.131-136, 1999.04.
162. H. Ijima, K. Nakazawa, M. Kaneko, H. Mizumoto, T. Matsushita, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi and K. Funatsu, The formation of a spheroid of primary hepatocytes and the expression of liver-specific functions depend on the characteristics of polyurethane foam, Journal of Artificial Organs, Vol.1,pp.83-88, 1998.01.
163. S. Furukawa, T. Iwabe, H. Ijima, K. Kawakami, Efficient immobilization of lipase by sol-gel method into organic-inorganic hybrid silicates, Proceedings of the 11th Symposium on Chemical Engineering Kyushu-Taejon/Chungnam, 1998.10.
164. S. Sakai, Y. Ishimaru, K. Yamamoto, H. Ijima, K. Kawakami, Development of biomaterials for microencapsulation of islets toward bioartificial pancreas, Proceedings of the 11th Symposium on Chemical Engineering Kyushu-Taejon/Chungnam, 1998.10.
165. A. Noguchi, T. Katsuno, K. Ohno, H. Ijima, K. Nakazawa, K. Funatsu, K. Kawakami, A novel method for evaluating the performance of an artificial liver using rats, Proceedings of the 11th Symposium on Chemical Engineering Kyushu-Taejon/Chungnam, 1998.10.
166. K. Funatsu, H. Ijima, K. Nakazawa, M. Kaneko, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, Preclinical test of hybrid artificial liver support system using liver failure dogs and pigs, Hepatology, 28, 4, 751A-751A, Vol.28, No.4, p.751A, 1998.10.
167. M. Kaneko, J. Fukuda, H. ijima, K. Nakazawa, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, K. Funatsu, Development of hybrid artificial liver support system using spheroid culture and application to warm ischemic liver failure in dog and pig as a preclinical test, Materials Science & Engineering C-Biomimetic and Supramolecular Systems, 10.1016/S0928-4931(98)00057-5, 6, 4, 245-248, Vol.6, No.4, pp.245-248, 1998.12.
168. K. Nakazawa, H. Ijima, M. Kaneko, T. Katsuno, T. Matsushita, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, K. Funatsu, Effect of in vitro hybrid artificial liver support system in human plasma of hepatic failure patient, Proceedings of the Joint International Meeting of the Japanese Association for Animal Cell Technology and the European Society for Animal Cell Technology (JAACT/ESACT'98), 1998.07.
169. H. Ijima, K. Nakazawa, M. Kaneko, T. Katsuno, T. Matsushita, T. Gion, M. Shimada, K. Shirabe, K. Takenaka, K. Sugimachi, K. Funatsu, Preclinical test of hybrid artificial liver support system using liver failure dogs and pigs, Proceedings of the Joint International Meeting of the Japanese Association for Animal Cell Technology and the European Society for Animal Cell Technology (JAACT/ESACT'98), 1998.07.
170. H. Ijima, K. Nakazawa, H. Mizumoto, T. Matsushita and K. Funatsu, Formation of a spherical multicellular aggregate (spheroid) of animal cells in the pores of polyurethane foam as a cell culture substratum and its application to a hybrid artificial liver, Journal of Biomaterials Science (Polymer Edition), 10.1163/156856298X00136, 9, 7, 765-778, Vol.9,pp.765-778, 1998.01.
171. H. Ijima, T. Matsushita, K. Nakazawa, Y. Fujii and K. Funatsu, Hepatocyte spheroids in polyurethane foams: Functional analysis and application for a hybrid artificial liver, Tissue Engineering, 10.1089/ten.1998.4.213, 4, 2, 213-226, Vol.4, No.2, pp.213-226, 1998.01.
172. Investigation of optimum culture condition for hybrid artificial liver module using PUF/porcine hepatocyte spheroid culture
K. Nakazawa, H. Ijima, M. Kaneko, T. Ito, T. Matsushita, T. Gion, K. Shirabe, M. Shimada, K. Takenaka, K. Sugimachi, K. Funatsu.
173. K. Funatsu, K. Matsunaga, H. Ijima, T. Matsushita, Finite element analysis of 3-dimensional flow in agitated bioreactors, Animal Cell Technology: Basic & Applied Aspects, 75-82, Vol.8, pp.75-82, 1997.01.
174. Development of drug metabolism simulator using PUF/hepatocyte spheroid culture. -Study of acetaminophen metabolism by hybrid artificial liver system-
K. Nakazawa, H. Mizumoto, H. Ijima, T. Matsushita, K. Funatsu.
175. Application of hybrid artificial liver using PUF/hepatocytes-spheroid packed-bed module to warm ischemic liver failure dog
T. Matsushita, S. Koyama, H. Ijima, K. Nakazawa, T. Gion, K. Shirabe, M. Shimada, K. Takenaka, K. Sugimachi, K. Funatsu.
176. Kazumori Funatsu, Yasuhiko Kawakubo, Hiroyuki Ijima, Taku Matsushita, High density culture of animal cells and its application to hybrid artificial liver support systems in Japan, Artificial Organs Today, Vol.3, No.4, pp.253-274, 1994.01.
177. H. Ijima, Y. Taniguchi, T. Matsushita and K. Funatsu, Application of three dimensional culture of adult rat hepatocytes in PUF pores for artificial liver support system, Animal Cell Technology: Basic & Applied Aspects, Vol.4,pp.81-86, 1992.01.
178. T. Matsushita, H. Ijima, N. Koide, K. Funatsu, High albumin production by multicellular spheroids of adult-rat hepatocytes formed in the pores of polyurethane foam, Applied Microbiology and Biotechnology, 36, 3, 324-326, Vol.36, No.3, pp.324-326, 1991.12.