71 research outputs found

    Enhanced in vivo osteogenesis by nanocarrier-fused bone morphogenetic protein-4

    Get PDF
    Purpose: Bone defects and nonunions are major clinical skeletal problems. Growth factors are commonly used to promote bone regeneration; however, the clinical impact is limited because the factors do not last long at a given site. The introduction of tissue engineering aimed to deter the diffusion of these factors is a promising therapeutic strategy. The purpose of the present study was to evaluate the in vivo osteogenic capability of an engineered bone morphogenetic protein-4 (BMP4) fusion protein. Methods: BMP4 was fused with a nanosized carrier, collagen-binding domain (CBD), derived from fibronectin. The stability of the CBD-BMP4 fusion protein was examined in vitro and in vivo. Osteogenic effects of CBD-BMP4 were evaluated by computer tomography after intramedullary injection without a collagen-sponge scaffold. Recombinant BMP-4, CBD, or vehicle were used as controls. Expressions of bone-related genes and growth factors were compared among the groups. Osteogenesis induced by CBD-BMP4, BMP4, and CBD was also assessed in a bone-defect model. Results: In vitro, CBD-BMP4 was retained in a collagen gel for at least 7 days while BMP4 alone was released within 3 hours. In vivo, CBD-BMP4 remained at the given site for at least 2 weeks, both with or without a collagen-sponge scaffold, while BMP4 disappeared from the site within 3 days after injection. CBD-BMP4 induced better bone formation than BMP4 did alone, CBD alone, and vehicle after the intramedullary injection into the mouse femur. -Bone-related genes and growth factors were expressed at higher levels in CBD-BMP4-treated mice than in all other groups, including BMP4-treated mice. Finally, CBD-BMP4 potentiated more bone formation than did controls, including BMP4 alone, when applied to cranial bone defects without a collagen scaffold. Conclusion: Altogether, nanocarrier-CBD enhanced the retention of BMP4 in the bone, thereby promoting augmented osteogenic responses in the absence of a scaffold. These results suggest that CBD-BMP4 may be clinically useful in facilitating bone formation

    A novel, visible light-induced, rapidly cross-linkable gelatin scaffold for osteochondral tissue engineering

    Get PDF
    Osteochondral injuries remain difficult to repair. We developed a novel photo-cross-linkable furfurylamine-conjugated gelatin (gelatin-FA). Gelatin-FA was rapidly cross-linked by visible light with Rose Bengal, a light sensitizer, and was kept gelled for 3 weeks submerged in saline at 37 degrees C. When bone marrow-derived stromal cells (BMSCs) were suspended in gelatin-FA with 0.05% Rose Bengal, approximately 87% of the cells were viable in the hydrogel at 24 h after photo-cross-linking, and the chondrogenic differentiation of BMSCs was maintained for up to 3 weeks. BMP4 fusion protein with a collagen binding domain (CBD) was retained in the hydrogels at higher levels than unmodified BMP4. Gelatin-FA was subsequently employed as a scaffold for BMSCs and CBD-BMP4 in a rabbit osteochondral defect model. In both cases, the defect was repaired with articular cartilage-like tissue and regenerated subchondral bone. This novel, photo-cross-linkable gelatin appears to be a promising scaffold for the treatment of osteochondral injury

    Pseudocyst in the Pancreatic Tail Associated with Chronic Pancreatitis Successfully Treated by Transpapillary Cyst Drainage

    Get PDF
    We report a 50-year-old male with pseudocysts in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage. He had previously undergone ultrasonography-guided percutaneous cyst drainage for a pancreatic pseudocyst in our hospital. He was readmitted due to abdominal pain and fever. Computed tomography showed recurrence of a pseudocyst in the pancreatic tail measuring 5 cm in diameter. Since conservative treatment failed, endoscopic retrograde pancreatography was performed. There was communication between the pseudocyst and the main pancreatic duct, and pancreatic duct stenosis proximal to the pseudocyst. First, transpapillary pancreatic duct drainage was performed using a plastic stent, but the pseudocyst did not decrease in size and became infected. After removal of the stent, a pigtail type nasocystic catheter was placed in the pseudocyst via the pancreatic duct. The pseudocyst infection immediately disappeared, and the pseudocyst gradually decreased and disappeared. After removal of the nasocystic catheter, no recurrence was observed. As transpapillary drainage of pancreatic pseudocyst, cyst drainage and pancreatic duct drainage have been reported. In our patient with pseudocyst in the pancreatic tail, duct drainage was ineffective and the pseudocyst was infected, whereas cyst drainage was very effective. We considered that cyst drainage by a nasocystic catheter was the first-line therapy as the transpapillary drainage of the pancreatic pseudocyst

    Interaction between human lymphoblastoid interferon and chemotherapeutic agents in vitro.

    Get PDF
    The combined effect of human lymphoblastoid interferon (HLBI) and anticancer agents on the growth of MOLT-4 was studied in vitro. The interferon showed a strikingly synergistic interaction in combination with aclarubicin, cytosine arabinoside or prednisolone. It was moderately synergistic in combination with adriamycin or 5-fluorouracil and tended to show additive effects with daunorubicin or vincristine. In vitro studies of combination chemotherapy with interferon and anticancer agents should yield valuable information as to the best combination for man.</p

    Biphasic Aire expression in early embryos and in medullary thymic epithelial cells before end-stage terminal differentiation

    Get PDF
    The roles of autoimmune regulator (Aire)–expressing medullary thymic epithelial cells (mTECs) in the organization of the thymic microenvironment for establishing self-tolerance are enigmatic. We sought to monitor the production and maintenance of Aire-expressing mTECs by a fate-mapping strategy in which bacterial artificial chromosome transgenic (Tg) mice expressing Cre recombinase under the control of the Aire regulatory element were crossed with a GFP reporter strain. We found that, in addition to its well recognized expression within mature mTECs, Aire was expressed in the early embryo before emergence of the three germ cell layers. This observation may help to explain the development of ectodermal dystrophy often seen in patients with AIRE deficiency. With the use of one Tg line in which Cre recombinase expression was confined to mTECs, we found that Aire+CD80high mTECs further progressed to an Aire−CD80intermediate stage, suggesting that Aire expression is not constitutive from after its induction until cell death but instead is down-regulated at the beginning of terminal differentiation. We also demonstrated that many mTECs of Aire-expressing lineage are in close contact with thymic dendritic cells. This close proximity may contribute to transfer of tissue-restricted self-antigens expressed by mTECs to professional antigen-presenting cells

    Imbalanced expression of polycistronic miRNA in acute myeloid leukemia

    Get PDF
    miR-1 and miR-133 are clustered on the same chromosomal loci and are transcribed together as a single transcript that is positively regulated by ecotropic virus integration site-1 (EVI1). Previously, we described how miR-133 has anti-tumorigenic potential through repression of EVI1 expression. It has also been reported that miR-1 is oncogenic in the case of acute myeloid leukemia (AML). Here, we show that expression of miR-1 and miR-133, which have distinct functions, is differentially regulated between AML cell lines. Interestingly, the expression of miR-1 and EVI1, which binds to the promoter of the miR-1/miR-133 cluster, is correlative. The expression levels of TDP-43, an RNA-binding protein that has been reported to increase the expression, but inhibits the activity, of miR-1, were not correlated with expression levels of miR-1 in AML cells. Taken together, our observations raise the possibility that the balance of polycistronic miRNAs is regulated post-transcriptionally in a hierarchical manner possibly involving EVI1,suggesting that the deregulation of this balance may play some role in AML cells with high EVI1 expression

    Japanese Society for Cancer of the Colon and Rectum (JSCCR) Guidelines 2014 for treatment of colorectal cancer

    Full text link

    A study on the animations of swaying and breaking trees based on a particle-based simulation

    Get PDF
    In this paper, we propose a particle-based simulation method to create the animations of swaying and breaking trees. Since the shapes of trees and their realistic motions are usually complex, it is difficult for us to create an animation of a swaying tree manually. Therefore, to produce films and image contents which contain a natural scene of swaying and breaking trees, it takes a lot of work to create the animation. To solve this problem, it is important that how to calculate interactions between a tree and wind to automatically generate the swaying and breaking motions of a tree by using a physical simulation. We model both a tree and wind as particles to simulate the interactions. The advantage of the particle-based method is that the method is robust for changing of the topology of wind and the branching structure of a tree. Our results show that the proposed method can naturally represent the breaking behavior of a tree and the wind flow around the tree by using the particle-based simulation of the wind
    corecore