Yu Sogo

National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan

Are you Yu Sogo?

Claim your profile

Publications (75)176.55 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Surface-mediated nonviral gene transfer systems using biocompatible apatite-based composite layers have potential use in tissue engineering applications. Herein, we investigated a relatively efficient system based on a DNA-lipid-apatite composite layer (DLp-Ap layer): an apatite (Ap) layer with immobilized DNA and lipid (Lp) complexes (DLp complexes). DLp-Ap layers were fabricated on substrates using supersaturated calcium phosphate coprecipitation solutions supplemented with DLp complexes, and the molecular compositions of the DLp-Ap layers were controlled by varying the net DNA concentrations and Lp/DNA ratios in the coprecipitation solutions. Increases in both the DNA concentration and Lp/DNA ratio in the coprecipitation solution increased the DLp complex content of the resulting DLp-Ap layer. However, a higher DLp complex content did not always provide increased gene transfer efficiency to the CHO-K1 cells, because there was a threshold content of approximately 10μg/cm(2). In addition, DLp-Ap layers with similar DLp complex contents exhibited different gene transfer efficiencies, most likely due to the different Lp/DNA ratios in the layers. Notably, the optimized Lp/DNA ratios in the coprecipitation solutions for maximizing the gene transfer efficiency were lower than those of the conventional particle-mediated lipofection systems. These findings will serve as a useful design guide for the preparation of DLp-Ap layers with high gene transfer efficiency.
    Colloids and surfaces B: Biointerfaces 07/2014; · 4.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Apatite can mediate gene transfer into cells by serving as a safe and biocompatible immobilization matrix for DNA and transfection reagents. Recently, an apatite layer that immobilized DNA-lipid complexes was prepared by a coprecipitation process in a supersaturated calcium phosphate solution. This composite layer (DNA-lipid-apatite layer) showed a higher gene transfer capability than an apatite layer with superficially adsorbed DNA-lipid complexes (DNA-lipid-adsorbed apatite layer). In this study, the DNA-lipid-apatite layer and the DNA-lipid-adsorbed apatite layer were compared for their physicochemical properties and gene transfer capabilities. The higher gene transfer capability of the DNA-lipid-apatite layer compared with that of the DNA-lipid-adsorbed apatite layer was reconfirmed by a luciferase assay using epithelial-like CHO-K1 cells. Physicochemical structure analyses showed that the DNA-lipid-apatite layer possessed a larger capacity for DNA-lipid complexes than the DNA-lipid-adsorbed apatite layer. The DNA-lipid-apatite layer released DNA-lipid complexes in a slow and sustained manner, whereas the DNA-lipid-adsorbed apatite layer released them in short bursts. Consequently, the release of DNA-lipid complexes from the DNA-lipid-apatite layer was larger in amount and longer in duration than release from the DNA-lipid-adsorbed apatite layer. This difference in release profiles may be responsible for the higher gene transfer capability of the DNA-lipid-apatite layer compared with that of the DNA-lipid-adsorbed apatite layer. The coprecipitation process and the resulting DNA-lipid-apatite layer have many applications in tissue engineering.
    Journal of Biomaterials Applications 02/2014; 28(6):937-45. · 2.64 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In our previous study, a fibroblast growth factor-2 (FGF-2)–apatite composite layer coated on titanium screws effectively prevented pin tract infection in rabbits because of enhanced wound healing; however, the FGF-2–apatite composite layers did not completely prevent pin tract infection. Thus, we recently developed a poly(ε-caprolactone) (PCL) sponge pad embedded with cefazolin sodium (+CEZ), which has a fast-acting bactericidal effect. The pad is placed on the skin around the screws. The purpose of this study was to determine the anti-infective efficacy of the +CEZ pad on the pin–skin interface of the FGF-2–apatite-coated titanium screws. The +CEZ pads were prepared by mixing PCL and CEZ in 1,4-dioxane, followed by freeze-drying and compaction. They were analyzed regarding their surface structure, in vitro CEZ release profile, and bactericidal activity. The FGF-2–apatite-coated screws were implanted percutaneously in bilateral rabbit proximal tibial metaphyses—with and without the +CEZ pad—for 4 weeks (n = 20). The + CEZ pads consisted of a porous matrix of PCL in which CEZ was embedded. The CEZ-release profile showed an initial burst on Day 1 and a sustained release lasting for 30 days. The +CEZ pad retained its bactericidal activity against Staphylococcus aureus after preincubation on an agar plate for 7 days. Based on visual inspection, the pin tract infection rate was successfully reduced from 72.2% to 15.0% with the +CEZ pad (p < 0.05), which reduced the bacterial count, especially S. aureus (p < 0.05). The histological inflammation rate of the soft tissues was also significantly lower with the +CEZ pad than without it (p < 0.05). The pin tract infection rate was reduced to one-fifth with the +CEZ pad. Using it as described improves infection resistance during percutaneous implantation.
    Asia-Pacific Journal of Sports Medicine, Arthroscopy, Rehabilitation and Technology. 01/2014; 1(2):54–61.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of the present study was to fabricate fibroblast growth factor (FGF)-2-apatite composite layers on titanium (Ti) pins in one step at 25 °C using a supersaturated calcium phosphate (CaP) solution, and to evaluate the physicochemical characteristics and biological effects of the coated Ti pins compared with coated Ti pins fabricated at 37 °C. Ti pins were immersed in a supersaturated CaP solution containing 0.5, 1.0, or 2.0 µg/mL FGF-2 at 25 °C for 24 h (25F0.5, 25F1.0, and 25F2.0) or containing 4.0 µg/mL FGF-2 at 37 °C for 48 h (37F4.0). Except for the 25F0.5, the chemical compositions and the mitogenic activity levels of FGF-2 of the composite layers formed by these two methods were similar, except for the Ca/P molar ratio, which was markedly smaller at 25 °C (1.55-1.56 ± 0.01-0.02, p = 0.0008-0.0045) than at 37 °C (1.67 ± 0.11). Thus, either the apatite was less mature or the amount of amorphous calcium phosphate was higher in the composite layer formed at 25 °C. In vivo, the pin tract infection rate by visual inspection for 37F4.0 (45%) was lower than that for 25F1.0 (80%, p = 0.0213), and the rate of osteomyelitis for 37F4.0 (35%) was lower than that for 25F0.5 (75%, p = 0.0341). The extraction torque for 37F4.0 (0.276 ± 0.117 Nm) was higher than that for 25F0.5 (0.192 ± 0.117 Nm, p = 0.0142) and that for 25F1.0 (0.176 ± 0.133 Nm, p = 0.0079). The invasion rate of S. aureus for 37F4.0 (35%) was lower than that for 25F0.5 (75%, p = 0.0110). On the whole, the FGF-2-apatite composite layer formed at 25 °C tended to be less effective at improving fixation strength in the bone-pin interface and resisting pin tract infections. These results suggest that the chemistry of the calcium phosphate matrix that embeds FGF-2, in addition to FGF-2 content and activity, has a significant impact on composite infection resistance and fixation strength.
    International Journal of Molecular Sciences 01/2014; 15(6):10252-10270. · 2.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the original version of the manuscript [1] there was an inadvertent error. The words "25 °C for 48 h" should be replaced with "25 °C for 24 h". The authors carried out the coating experiments at 25 °C for 1, 3, 6, 12, 24 and 48 h. The apatite coatings formed at 25 °C for 24 and 48 h were found to be identical in physicochemical nature, which was revealed by SEM, EDX, XRD and chemical analysis. Thus, in the animal experiments, the authors used apatite-coated Ti pins fabricated at 25 °C for 24 h. Several corrections are thus required in the abstract, the main text, the figure legends, and the figures (Table 1). The authors would like to apologize for any inconvenience this may have caused to readers of the journal. [...].
    International Journal of Molecular Sciences 01/2014; 15(6):9789-9792. · 2.46 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Proton-beam radiotherapy (PBT) has been shown to be effective to hepatocellular carcinoma (HCC) as a nonsurgical local treatment option. However, HCC still remains as one of the most difficult cancers to be cured because of frequent recurrences. Thus, methods to inhibit the recurrence need to be explored. To prevent the HCC recurrence, we here report on a prospective phase I study of 'in situ' tumor vaccination using CalTUMP, a newly developed immunoadjuvant consisting of BCG extract bound to hydroxyapatite and microparticulated tuberculin, following local PBT for HCC. Patients with locally advanced recurrent HCC, which had been heavily pretreated with various treatments, were enrolled. PBT was performed with the conventional method to the target HCC. Subsequently, CalTUMP was injected into the same irradiated-tumor three times at one-week intervals. Three dose-levels of CalTUMP (1/10, 1/3, and 1/1) were administered to 3 patients each. Vital signs, blood samples, ultrasound, and computed tomographic scans were monitored to evaluate the safety. Three intratumoral injections of CalTUMP following PBT (median dose: 72.6 GyE) were accomplished in 9 patients. Transient low-grade fever and minor laboratory changes were observed in 7 patients after CalTUMP injections. No other treatment-related adverse events were observed. Median progression-free survival was 6.0 months (range: 2.1-14.2) and 4 patients were progression-free for more than 1 year. Intratumoral injection of CalTUMP following PBT was feasible and safe in patients with heavily pre-treated HCC. Further clinical studies to evaluate the efficacy of this in situ tumor vaccination are warranted.
    Radiation Oncology 10/2013; 8(1):239. · 2.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Zn-, and Mg-containing tricalcium phosphates (TCPs) loaded with a hydrothermal extract of a human tubercle bacillus (HTB) were prepared by immersing Zn-TCP and Mg-TCP in HTB-containing supersaturated calcium phosphate solutions. The in vitro and in vivo immunogenic activities of the HTB-loaded Zn-, and Mg-TCPs (Zn-Ap-HTB and Mg-Ap-HTB, respectively) were evaluated as potential immunopotentiating adjuvants for cancer immunotherapy. The Zn-Ap-HTB and Mg-Ap-HTB adjuvants showed no obvious cytotoxicity and more effectively stimulated granulocyte-macrophage colony-stimulating factor (GM-CSF) secretion by macrophage-like cells than unprocessed HTB or HTB-loaded TCP (T-Ap-HTB) in vitro. Zn-Ap-HTB and Mg-Ap-HTB mixed with liquid-nitrogen-treated tumor tissue markedly inhibited the in vivo development of rechallenged Lewis lung carcinoma (LLC) cells compared with T-Ap-HTB and the unprocessed HTB mixed liquid-nitrogen-treated tumor tissue. Zn-Ap-HTB and Mg-Ap-HTB contributed to eliciting potent systemic antitumor immunity in vivo.
    Scientific Reports 07/2013; 3:2203. · 5.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Submicrospheres composed of amorphous calcium phosphate (ACP) and DNA spontaneously assembled on a substrate via homogeneous calcium phosphate (CaP) nucleation followed by deposition in a highly supersaturated labile CaP solution. The nanocomposite layer of sphere assembly showed higher gene transfer efficiency than a continuous film nanocomposite layer previously fabricated via heterogeneous nucleation in a metastable supersaturated solution.
    CrystEngComm 06/2013; 15(25):4994-4997. · 3.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A tissue-engineered endothelial layer was prepared by culturing endothelial cells on a fibroblast growth factor-2 (FGF-2)–l-ascorbic acid phosphate magnesium salt n-hydrate (AsMg)–apatite (Ap) coated titanium plate. The FGF-2–AsMg–Ap coated Ti plate was prepared by immersing a Ti plate in supersaturated calcium phosphate solutions supplemented with FGF-2 and AsMg. The FGF-2–AsMg–Ap layer on the Ti plate accelerated proliferation of human umbilical vein endothelial cells (HUVECs), and showed slightly higher, but not statistically significant, nitric oxide release from HUVECs than on as-prepared Ti. The endothelial layer maintained proper function of the endothelial cells and markedly inhibited in vitro platelet adhesion. The tissue-engineered endothelial layer formed on the FGF-2–AsMg–Ap layer is promising for ameliorating platelet activation and thrombus formation on cardiovascular implants.
    Science and Technology of Advanced Materials 05/2013; 14(3):035002. · 3.75 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A facile method to synthesize mesoporous AlOOH nanofibers using inorganic aluminum salts as the aluminum source and urea as the pore-forming and precipitating agent is reported. The uptake of AlOOH by macrophage-like cells is about 2 times of commercial Alum. The AlOOH adjuvant markedly stimulates the immune responses compared to the commercial Alum adjuvant.
    RSC Advances 05/2013; 3(22):8164-8167. · 3.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Commonly used aluminum hydroxide (Alum) adjuvant provokes a strong type 2 helper T cell (Th2) response for mediating antibody production, but is rather ineffective for disease prevention that requires type 1 helper T cell (Th1) response for mediating cellular immunity in human vaccination. Here, for the purpose of inducing Th1 anti-tumor immunity, a mesoporous silica (MS)-based adjuvant is prepared. Three kinds of MS particles with nearly identical particle size and surface area but different pore sizes of 4, 7 and 10 nm were prepared. No serious in vitro cytotoxicity was observed for the MS particles at 5, 20, 50 and 100 μg/mL. Pathogen-associated molecular patterns (PAMPs) were immobilized with apatite (Ap) on MS to prepare the MS-based and PAMP-loaded adjuvants (MS-Ap-PAMP adjuvants). Macrophage-like cells cultured in the presence of MS-Ap-PAMP adjuvant with a MS pore size of 10 nm showed the maximum in vitro immunogenic activity. Injection of the MS-Ap-PAMP adjuvant with a MS pore size of 10 nm in combination with liquid-nitrogen-treated tumor tissue (derived from Lewis lung carcinoma cells) to C57BL/6 mice markedly inhibited the development of re-challenged tumor in vivo, while no such antitumor immunity was induced in injection of Alum mixed with PAMP in combination with liquid-nitrogen-treated tumor tissue. The MS-Ap-PAMP adjuvant contributed to the elicitation of a potent systemic Th1 antitumor immunity in vivo.
    Journal of Biomedical Materials Research Part A 05/2013; · 2.83 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Surface functionalization of highly bioresorbable biomaterials has been a challenging subject. The objective of our research is to establish a calcium phosphate (CaP) coating technique on a bioresorbable bone substitute material: hydroxyapatite and collagen nanocomposite for surface functionalization using supersaturated solutions. A coating technique using a metastable supersaturated solution was inapplicable to the nanocomposite. In contrast, CaP coating was successfully prepared on the nanocomposite by using labile supersaturated solutions when the solution concentration was adjusted to a certain range.
    Chemistry Letters 05/2013; · 1.59 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Apatite (Ap), laminin-apatite composite (L5Ap, L10Ap, L20Ap and L40Ap) and albumin-apatite (AlbAp) composite layers were prepared on titanium (Ti) using a supersaturated calcium phosphate solution supplemented with laminin (0, 5, 10, 20 and 40 μg ml(-1)) or albumin (800 μg ml(-1)). With an increase in the concentrations of laminin in the supersaturated calcium phosphate solutions, the amounts of laminin immobilized on the Ti increased. The number of human umbilical vein endothelial cells (HUVECs) adhered to the laminin-apatite composite layers were remarkably higher than those to the untreated Ti, Ap layer and AlbAp composite layer. The number of cells adhered to the L40Ap was 4.3 times the untreated Ti. Moreover, cells adhered to the laminin-apatite composite layers showed significantly higher cell retention under the physiological shear stress for 1 h and 2 h than those to the untreated Ti, Ap layer and AlbAp composite layer. The number of cells remaining on the L40Ap under the physiological shear stress for 2 h was 9.5 times that of the untreated Ti. The laminin-apatite composite layer is a promising interfacial layer for endothelialization of blood-contacting materials.
    Journal of The Royal Society Interface 04/2013; 10(81):20130014. · 4.91 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Conventionally used adjuvants alone are insufficient for triggering cell-mediated immunity, although they have been successfully developed to elicit protective antibody responses in some vaccines. Here, with the aim of eliciting cell-mediated immunity, pathogen-associated molecular patterns (PAMPs) were immobilized with apatite within the pores and on the surface of mesoporous silica (MS) with particle sizes from 30 to 200 nm to prepare novel MS-Ap-PAMP adjuvants, which showed markedly improved cell-mediated anti-tumor immunity than commercial Alum adjuvant in vitro and in vivo. The toxicity and antitumor immunity of the MS-Ap-PAMP adjuvants were evaluated in vitro and in vivo. MS with a particle size of 200 nm showed minimum in vitro cytotoxicity to NIH3T3 cells, particularly at concentrations no higher than 100 μg/mL. In particular, apatite precipitation within the pores and on the surface of MS decreased the in vitro cytotoxicity of MS particles. The MS-Ap-PAMP adjuvants showed the maximum in vitro immunogenic activity among original culture medium, PAMP and Alum-PAMP. Moreover, injection of the MS-Ap-PAMP adjuvant in combination with liquid-N2-treated tumor tissue (derived from Lewis lung carcinoma cells) to C57BL/6 mice markedly inhibited in vivo tumor recurrence and development of re-challenged tumor than those with commercial Alum adjuvant. The MS-Ap-PAMP adjuvant contributed to the elicitation of a potent systemic antitumor immunity without obvious toxicity in vivo.
    Acta biomaterialia 03/2013; · 5.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although fibroblast growth factor 2 (FGF2) is a promising agent for treating brain infarction, current methods of FGF2 administration are associated with a short circulating half-life. An FGF2 apatite coating was developed as a slow-releasing drug delivery system (DDS) by forming an FGF2/calcium phosphate composite layer. Hydroxyapatite was coated with high or low doses of FGF2, denoted as FGF-high and FGF-low. This study investigated the efficacy of the coating as angiogenesis therapy for brain infarction. Rats were subjected to permanent occlusion of the middle cerebral artery, an FGF2 apatite-coated implant was inserted, and the rat brains were removed 2 weeks after implantation. Rats in groups treated with FGF-high had significantly smaller areas of brain infarction, particularly in the external capsule and the lateral side of the putamen, and better capillary density than rats in groups treated with non-FGF2 apatite-coated implants. Histologic analysis indicated that the new vessels were larger and had thicker walls in the FGF2 apatite-coated groups than in the non-FGF2 groups. Fluorescence immunohistochemistry of the peri-infarction region showed that FGF2 released from FGF2 apatite-coated implants might have biological activity. Moreover, fluorescence immunohistochemistry showed that released FGF2 influenced microglia cells. This new FGF2 DDS involving an FGF2 apatite coating can prevent infarction of the penumbra through the multipotential effects of FGF2.
    Biochemical and Biophysical Research Communications 01/2013; · 2.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The synthesis of mesoporous silica/calcium phosphate composite loaded with the immunopotentiator tuberculin purified protein derivative (PPD-MS/CaP) as an effective adjuvant for cancer immunotherapy is reported here. The PPD-MS/CaP adjuvant is prepared by immersing mesoporous silica in a supersaturated calcium phosphate solution supplemented with the immunopotentiator PPD for 24 h. PPD is coprecipitated with calcium phosphate inside and on the surface of mesoporous silica. By loading the immunopotentiator PPD in the PPD-MS/CaP adjuvant, an enhanced activation of antigen-presenting cells, such as GM-CSF secretion by THP-1 differentiated macrophages, is obtained probably due to sustained PPD release and an efficient cellular uptake of PPD. The PPD-MS/CaP adjuvant mixed with liquid-N(2) -treated tumor tissue effectively triggers anti-tumor immune response and markedly inhibits in vivo tumor growth. The PPD-MS/CaP adjuvant is a promising alternative for cancer immune therapy.
    Advanced healthcare materials. 01/2013;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Calcium phosphate (CaP) coating is an effective technique for surface functionalization of biomaterials. The objective of our research is to prepare calcium phosphate (CaP) coatings on a hydroxyapatite/collagen (HAp/Col) nanocomposite and subsequently provide it with gene delivery function through the immobilization of DNA in the coating. We have specifically selected the HAp/Col nanocomposite since it has the high potential as bone substitutes due to its similar composition, nanostructure, and biological properties to those of human bone. CaP coatings consisting of different sized particles were prepared on the HAp/Col nanocomposite membrane by immersing it in supersaturaterd CaP solutions (so-called RKM solutions) with the varied Ca and P concentration levels. We immobilized DNA in the CaP coatings together with lipid and fibronectin by supplementing DNA, lipid, and fibronectin to the RKM solutions (DLF-RKM solutions). Gene transfer capability of the resulting HAp/Col nanocomposite membrane was improved with decreasing concentration level of the DLF-RKM solution. It was confirmed that the present CaP coating technique was effective in providing the HAp/Col nanocomposite membrane with gene transfer capability and that the Ca and P concentration level of the DLF-RKM solution was a controlling factor affecting the gene transfer efficiency.
    Key Engineering Materials 01/2013; 529-530:490-494.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Increased fixation strength of the bone-pin interface is important for inhibiting pin loosening after external fixation. In a previous study, an apatite (Ap) layer was formed on anodically oxidized titanium (Ti) pins by immersing them in an infusion fluid-based supersaturated calcium phosphate solution at 37 °C for 48 h. In the present study, an Ap layer was also successfully formed using a one-step method at 25 °C for 48 h in an infusion fluid-based supersaturated calcium phosphate solution, which is clinically useful due to the immersion temperature. After percutaneous implantation in a proximal tibial metaphysis for four weeks in rabbits (n = 20), the Ti pin coated with the Ap layer showed significantly increased extraction torque compared with that of an uncoated Ti screw even with partial osteomyelitis present, owing to dense bone formation on the Ap layer in the cortical and medullary cavity regions. When the infection status was changed from "no osteomyelitis" to "partial osteomyelitis," the extraction torque in the Ap group with "partial osteomyelitis" was almost identical to that for "no osteomyelitis" cases. These results suggest that the Ap layer formed by the room temperature process could effectively improve the fixation strength of the Ti pin for external fixation clinically even with partial osteomyelitis present.
    International Journal of Molecular Sciences 01/2013; 14(12):24366-79. · 2.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: DNA-apatite composite layer (D-Ap layer) and DNA-lipid-apatite composite layer (DLp-Ap layer) were prepared on ceramic hydroxyapatite disk and scaffold using supersaturated calcium phosphate solutions supplemented with 0.5–5 μg/mL plasmid and 0–10 μL/mL lipid transfection reagent FuGENE®. Both in vitro and in vivo studies were carried out using mesenchymal stem cells (MSCs) and two kinds of gene (luciferase and bone morphogenetic protein (BMP)-2) for demonstrating potential application of the gene transfer system using the D-Ap and DLp-Ap layers in bone tissue engineering. In the in vitro study using luciferase gene, the DLp-Ap layers showed 1–2 orders of magnitudes higher gene transfer efficiency to MSCs than the D-Ap layer. In the in vivo study using BMP-2 gene, DLp-Ap layer slightly increased BMP-2 protein concentration than D-Ap layer, thereby enhancing their osteogenic differentiation than D-Ap layer. The present gene transfer system using the DLp-Ap layers, with the advantages of good biocompatibility, bone-bonding ability, and efficacy in in vitro and in vivo gene transfer to MSCs, would be useful in bone tissue engineering.
    Materials Science and Engineering: C. 01/2013; 33(1):512–518.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to evaluate the efficacy of suspensions of zinc-containing tricalcium phosphate (TCP) in the healing of thermal burns in rats. β-ZnTCP containing 10 mol % zinc, α-ZnTCP containing 0.9 mol % zinc, and ZnSO(4) ·(H(2) O)(7) (ZnSO(4) ) were used. The injections were prepared to suspend ZnSO(4) , α-ZnTCP, and β-ZnTCP powders in 2 mL of 1% sodium alginate saline solution containing 2 mg of Zn. In vitro Zn release rates were measured in simulated body fluid. The release of Zn from ZnSO(4) was very fast, but that from α-ZnTCP and β-ZnTCP was slowed by transformation to hydroxyapatite. The suspensions were injected into group C (control), D1 (ZnSO(4) ), D2 (α-ZnTCP), and D3 (β-ZnTCP) rats after thermal burns treatment for 3 h. The area under the curve for the plasma Zn for group D1 was the highest, and the order was groups D1 > D2 ≥ D3 ≥ C. The wounded area (Aw) of group D1 had almost the same profile as that of group C, and the Aw at 18 days was about 20%. In contrast, the Aw of group D2 and D3 decreased, and on day 15 was 8% and 37%, respectively. The results indicated that the healing process was shorter in the rats given α-ZnTCP and β-ZnTCP than those given ZnSO(4) or the control. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
    Journal of Biomedical Materials Research Part A 12/2012; · 2.83 Impact Factor

Publication Stats

389 Citations
176.55 Total Impact Points

Institutions

  • 2002–2014
    • National Institute of Advanced Industrial Science and Technology
      Tsukuba, Ibaraki, Japan
  • 2012
    • Musashino University
      • Faculty of Pharmacy
      Edo, Tōkyō, Japan
  • 2011–2012
    • Waseda University
      • • Faculty of Science and Engineering
      • • Department of Earth Science, Resources and Environmental Engineering
      Tokyo, Tokyo-to, Japan
    • Ibaraki Prefectural University of Health Sciences
      Ibaragi, Ōsaka, Japan
    • Tsukuba Research Institute
      Edo, Tōkyō, Japan
  • 2008–2011
    • The Nippon Dental University
      • Department of Oral and Maxillofacial Surgery
      Tokyo, Tokyo-to, Japan
  • 2007–2010
    • University of Tsukuba
      • • Department of Neurosurgery
      • • Institute of Clinical Medicine
      Tsukuba, Ibaraki-ken, Japan