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Kreimendahl F, Köpf M, Thiebes AL, Duarte Campos DF, Blaeser A, Schmitz-Rode T, Apel C, Jockenhoevel S, Fischer H. Three-Dimensional Printing and Angiogenesis: Tailored Agarose-Type I Collagen Blends Comprise Three-Dimensional Printability and Angiogenesis Potential for Tissue-Engineered Substitutes. Tissue Eng Part C Methods 2017; 23:604-615. [DOI: 10.1089/ten.tec.2017.0234] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- Franziska Kreimendahl
- Department of Biohybrid and Medical Textiles (BioTex), AME-Helmholtz Institute for Biomedical Engineering and ITA-Institut für Textiltechnik, RWTH Aachen University, Aachen, Germany
| | - Marius Köpf
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Anja Lena Thiebes
- Department of Biohybrid and Medical Textiles (BioTex), AME-Helmholtz Institute for Biomedical Engineering and ITA-Institut für Textiltechnik, RWTH Aachen University, Aachen, Germany
| | - Daniela F. Duarte Campos
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Andreas Blaeser
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Thomas Schmitz-Rode
- Department of Biohybrid and Medical Textiles (BioTex), AME-Helmholtz Institute for Biomedical Engineering and ITA-Institut für Textiltechnik, RWTH Aachen University, Aachen, Germany
| | - Christian Apel
- Department of Biohybrid and Medical Textiles (BioTex), AME-Helmholtz Institute for Biomedical Engineering and ITA-Institut für Textiltechnik, RWTH Aachen University, Aachen, Germany
| | - Stefan Jockenhoevel
- Department of Biohybrid and Medical Textiles (BioTex), AME-Helmholtz Institute for Biomedical Engineering and ITA-Institut für Textiltechnik, RWTH Aachen University, Aachen, Germany
| | - Horst Fischer
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Aachen, Germany
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Gettler BC, Zakhari JS, Gandhi PS, Williams SK. Formation of Adipose Stromal Vascular Fraction Cell-Laden Spheroids Using a Three-Dimensional Bioprinter and Superhydrophobic Surfaces. Tissue Eng Part C Methods 2017; 23:516-524. [PMID: 28665236 DOI: 10.1089/ten.tec.2017.0056] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The therapeutic infusion of adipose-derived stromal vascular fraction (SVF) cells for the treatment of multiple diseases, has progressed to numerous human clinical trials; however, the often poor retention of the cells following implantation remains a common drawback of direct cell injection. One solution to cellular retention at the injection site has been the use of biogels to encapsulate cells within a microenvironment before and upon implantation. The current study utilized three-dimensional bioprinting technology to evaluate the ability to form SVF cell-laden spheroids with collagen I as a gel-forming biomatrix. A superhydrophobic surface was created to maintain the bioprinted structures in a spheroid shape. A hydrophilic disc was printed onto the hydrophobic surface to immobilize the spheroids during the gelation process. Conditions for the automated rapid formation of SVF cell-laden spheroids were explored, including time/pressure relationships for spheroid extrusion during bioprinting. The formed spheroids maintain SVF viability in both static culture and dynamic spinner culture. Spheroids also undergo a time-dependent contraction with the retention of angiogenic sprout phenotype over the 14-day culture period. The use of a biphilic surface exhibiting both superhydrophobicity to maintain the spheroid shape and a hydrophilicity to immobilize the spheroid during gel formation produces SVF cell-laden spheroids that can be immediately transplanted for therapeutic applications.
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Affiliation(s)
- Brian C Gettler
- Cardiovascular Innovation Institute, University of Louisville , Louisville, Kentucky
| | - Joseph S Zakhari
- Cardiovascular Innovation Institute, University of Louisville , Louisville, Kentucky
| | - Piyani S Gandhi
- Cardiovascular Innovation Institute, University of Louisville , Louisville, Kentucky
| | - Stuart K Williams
- Cardiovascular Innovation Institute, University of Louisville , Louisville, Kentucky
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Mikhailov OV. Polycyclic 3d-metalchelates formed owing to inner-sphere transmutations in the gelatin matrix: synthesis and structures. REV INORG CHEM 2017. [DOI: 10.1515/revic-2017-0003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractProcesses of synthesis of polycyclic compounds containing various 3d-elements, proceeding in gelatin matrix in the systems M(II) ion – (N,S)- or (N,O,S)-containing organic compound A – mono- or dicarbonyl-containing organic compound B, resulting in one of a variety of inner-sphere transmutations, namely “self-assembly”, have been considered and discussed. The chemical nature of the final products of such a synthesis formed under these specific conditions have been compared with the chemical nature of the final products formed by similar synthesis in solutions. It has been noted that in many cases, the nature and chemical composition of these products differ substantially. Specific features of the density functional theory calculated molecular structures of the metal macrocyclic compounds that can be formed due to such a synthesis in the systems indicated above have been discussed, too. The review covers the period 1990–2016.
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Affiliation(s)
- Oleg V. Mikhailov
- Department of Analytical Chemistry, Kazan National Research Technological University, K. Marx Street 68, 420015 Kazan, Russia
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54
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Fibroblasts as maestros orchestrating tissue regeneration. J Tissue Eng Regen Med 2017; 12:240-251. [DOI: 10.1002/term.2405] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 12/05/2016] [Accepted: 01/09/2017] [Indexed: 12/12/2022]
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55
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Krishnaswamy VR, Balaguru UM, Chatterjee S, Korrapati PS. Dermatopontin augments angiogenesis and modulates the expression of transforming growth factor beta 1 and integrin alpha 3 beta 1 in endothelial cells. Eur J Cell Biol 2017; 96:266-275. [DOI: 10.1016/j.ejcb.2017.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 02/28/2017] [Accepted: 02/28/2017] [Indexed: 02/01/2023] Open
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Tian H, Ketova T, Hardy D, Xu X, Gao X, Zijlstra A, Blobe GC. Endoglin Mediates Vascular Maturation by Promoting Vascular Smooth Muscle Cell Migration and Spreading. Arterioscler Thromb Vasc Biol 2017; 37:1115-1126. [PMID: 28450296 PMCID: PMC5444426 DOI: 10.1161/atvbaha.116.308859] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 04/19/2017] [Indexed: 11/16/2022]
Abstract
Supplemental Digital Content is available in the text. Objective— Endoglin, a transforming growth factor-β superfamily coreceptor, is predominantly expressed in endothelial cells and has essential roles in vascular development. However, whether endoglin is also expressed in vascular smooth muscle cells (VSMCs), especially in vivo, remains controversial. Furthermore, the roles of endoglin in VSMC biology remain largely unknown. Our objective was to examine the expression and determine the function of endoglin in VSMCs during angiogenesis. Approach and Results— Here, we determine that endoglin is robustly expressed in VSMCs. Using CRISPR/CAS9 knockout and short hairpin RNA knockdown in the VSMC/endothelial coculture model system, we determine that endoglin in VSMCs, but not in endothelial cells, promotes VSMCs recruitment by the endothelial cells both in vitro and in vivo. Using an unbiased bioinformatics analysis of RNA sequencing data and further study, we determine that, mechanistically, endoglin mediates VSMC recruitment by promoting VSMC migration and spreading on endothelial cells via increasing integrin/FAK pathway signaling, whereas endoglin has minimal effects on VSMC adhesion to endothelial cells. In addition, we further determine that loss of endoglin in VSMCs inhibits VSMC recruitment in vivo. Conclusions— These studies demonstrate that endoglin has an important role in VSMC recruitment and blood vessel maturation during angiogenesis and also provide novel insights into how discordant endoglin function in endothelial and VSMCs may regulate vascular maturation and angiogenesis.
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Affiliation(s)
- Hongyu Tian
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.);
| | - Tatiana Ketova
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.)
| | - Duriel Hardy
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.)
| | - Xiaojiang Xu
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.)
| | - Xia Gao
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.)
| | - Andries Zijlstra
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.)
| | - Gerard C Blobe
- From the Division of Medical Oncology, Department of Medicine (H.T., D.H., G.C.B.) and Department of Pharmacology and Cancer Biology (G.C.B.), Duke University Medical Center, Durham, NC; Department of Pathology, Microbiology, and Immunology (T.K., A.Z.) and Department of Cancer Biology (A.Z.), Vanderbilt University, Nashville, TN; Integrative Bioinformatics, National Institute of Environmental Health Sciences, Research Triangle Park, NC (X.X.); Department of Cell Biology, Duke University School of Medicine, Durham, NC (X.G.); and Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN (A.Z.);
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Masuda R, Kudo M, Dazai Y, Mima T, Koide T. Collagen-like antimicrobial peptides. Biopolymers 2017; 106:453-9. [PMID: 27271210 DOI: 10.1002/bip.22791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Revised: 11/19/2015] [Accepted: 11/29/2015] [Indexed: 02/03/2023]
Abstract
Combinatorial library composed of rigid rod-like peptides with a triple-helical scaffold was constructed. The component peptides were designed to have various combinations of basic and neutral (or hydrophobic) amino acid residues based on collagen-like (Gly-Pro-Yaa)-repeating sequences, inspired from the basic and amphiphilic nature of naturally occurring antimicrobial peptides. Screening of the peptide pools resulted in identification of antimicrobial peptides. A structure-activity relationship study revealed that the position of Arg-cluster at N-terminus and cystine knots at C-terminus in the triple helix significantly contributed to the antimicrobial activity. The most potent peptide RO-A showed activity against Gram-negative Escherichia coli and Gram-positive Bacillus subtilis. In addition, Escherichia coli exposed to RO-A resulted in abnormal elongation of the cells. RO-A was also shown to have remarkable stability in human serum and low cytotoxicity to mammalian cells. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 453-459, 2016.
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Affiliation(s)
- Ryo Masuda
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan.,Research Institute for Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan
| | - Masakazu Kudo
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan
| | - Yui Dazai
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan
| | - Takehiko Mima
- Department of Bacteriology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8558, Japan
| | - Takaki Koide
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan
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58
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A Novel Procedure for the Immediate Reconstruction of Severely Resorbed Alveolar Sockets for Advanced Periodontal Disease. Case Rep Dent 2017; 2017:9370693. [PMID: 28250998 PMCID: PMC5303851 DOI: 10.1155/2017/9370693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 12/21/2016] [Indexed: 11/18/2022] Open
Abstract
Background. Several clinical techniques and a variety of biomaterials have been introduced over the years in an effort to overcome bone remodeling and resorption after tooth extraction. However, the predictability of these procedures in sockets with severely resorbed buccal/lingual plate due to periodontal disease is still unknown. Case Description. A patient with advanced periodontitis underwent extraction of upper right lateral and central incisors. The central incisor exhibited complete buccal bone plate loss and a 9 mm vertical bone deficiency on its palatal side. The alveolar sockets were filled with collagen sponge and covered with a nonresorbable high-density PTFE membrane. Primary closure was not attained and any rigid scaffold material was not used. Histologic analysis provided evidence of new bone formation. At 12 months a cone-beam computed tomographic scan revealed enough bone volume to insert two conventional dental implants in conjunction with minor horizontal bone augmentation procedures. Clinical Implications. This case report would seem to support the potential of the proposed reconstructive approach in changing the morphology of severely resorbed alveolar sockets, minimizing the need for advanced bone regeneration procedures during implant placement.
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Açil Y, Ghoniem AA, Gülses A, Kisch T, Stang F, Wiltfang J, Gierloff M. Suppression of osteoblast-related genes during osteogenic differentiation of adipose tissue derived stromal cells. J Craniomaxillofac Surg 2016; 45:33-38. [PMID: 27842921 DOI: 10.1016/j.jcms.2016.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/31/2016] [Accepted: 10/11/2016] [Indexed: 11/25/2022] Open
Abstract
Recent studies indicated a lower osteogenic differentiation potential of adipose tissue-derived stromal cells (ASCs) compared to bone marrow derived mesenchymal stromal cells. The aim of this study was to evaluate the effects of potent combinations of highly osteogenic bone morphogenetic proteins (BMPs) in order to enhance the osteogenic differentiation potential of ASCs. Human ASCs were cultured for 10 days in the presence of osteogenic medium consisting of dexamethasone, ß-glycerophosphate and ascorbat-2-phosphate (OM) supplemented with BMP-2, BMP-6, BMP-9+IGF-2 and BMP-2,-6,-9 (day 1+2: 50 ng/ml, days 3-6: 100 ng/ml, days 7-10: 200 ng/ml). The formation of the osteoblast phenotype was evaluated by quantification of osteoblast-related marker genes using real-time polymerase chain reaction (RT-PCR). Matrix mineralization was assessed by Alizarin Red S staining. Statistical analysis was carried out using the one-way analysis of variance (ANOVA) followed by the Scheffe's post hoc procedure. Osteogenic medium (OM) significantly increased the expression of alkaline phosphatase (ALP) and osteocalcin (p < 0.05) and led to a stable matrix mineralization. Under the influence of BMP-9+IGF-2 and BMP-2,-6,-9 the ALP expression further increased compared to ASCs cultured with OM only (p < 0.01). However, multiple osteogenic markers showed no change or decreased under the influence of OM and BMP combinations (p < 0.05). The current results indicate a restricted osteogenic differentiation potential of ASCs and suggest careful reconsideration of their use in bone tissue engineering applications.
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Affiliation(s)
- Yahya Açil
- Department of Oral & Maxillofacial Surgery (Head of Scientific Laboratories: Prof. Yahya Açil, Head: Prof. Dr. Jörg Wiltfang), Christian-Albrechts University, Kiel, Germany
| | - Amir Alexander Ghoniem
- Department of Oral & Maxillofacial Surgery (Head of Scientific Laboratories: Prof. Yahya Açil, Head: Prof. Dr. Jörg Wiltfang), Christian-Albrechts University, Kiel, Germany
| | - Aydin Gülses
- Center for Oral and Dental Health, Kars, Turkey.
| | - Tobias Kisch
- Department of Plastic Surgery, University of Lübeck, Lübeck, Germany
| | - Felix Stang
- Department of Plastic Surgery, University of Lübeck, Lübeck, Germany
| | - Jörg Wiltfang
- Department of Oral & Maxillofacial Surgery (Head of Scientific Laboratories: Prof. Yahya Açil, Head: Prof. Dr. Jörg Wiltfang), Christian-Albrechts University, Kiel, Germany
| | - Matthias Gierloff
- Department of Plastic Surgery, University of Lübeck, Lübeck, Germany
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Wang JK, Xiong GM, Luo B, Choo CC, Yuan S, Tan NS, Choong C. Surface modification of PVDF using non-mammalian sources of collagen for enhancement of endothelial cell functionality. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:45. [PMID: 26758892 PMCID: PMC4710638 DOI: 10.1007/s10856-015-5651-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 12/12/2015] [Indexed: 06/05/2023]
Abstract
Although polyvinylidene fluoride (PVDF) is non-toxic and stable in vivo, its hydrophobic surface has limited its bio-applications due to poor cell-material interaction and thrombus formation when used in blood contacting devices. In this study, surface modification of PVDF using naturally derived non-mammalian collagen was accomplished via direct surface-initiated atom transfer radical polymerisation (SI-ATRP) to enhance its cytocompatibility and hemocompatibility. Results showed that Type I collagen was successfully extracted from fish scales and bullfrog skin. The covalent immobilisation of fish scale-derived collagen (FSCOL) and bullfrog skin-derived collagen (BFCOL) onto the PVDF surface improves the attachment and proliferation of human umbilical vein endothelial cells (HUVECs). Furthermore, both FSCOL and BFCOL had comparable anti-thrombogenic profiles to that of commercially available bovine collagen (BVCOL). Also, cell surface expression of the leukocyte adhesion molecule was lower on HUVECs cultured on non-mammalian collagen surfaces than on BVCOL, which is an indication of lower pro-inflammatory response. Overall, results from this study demonstrated that non-mammalian sources of collagen could be used to confer bioactivity to PVDF, with comparable cell-material interactions and hemocompatibility to BVCOL. Additionally, higher expression levels of Type IV collagen in HUVECs cultured on FSCOL and BFCOL were observed as compared to BVCOL, which is an indication that the non-mammalian sources of collagen led to a better pro-angiogenic properties, thus making them suitable for blood contacting applications.
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Affiliation(s)
- Jun Kit Wang
- Residues and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute (NEWRI), Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore
- Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Gordon Minru Xiong
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Baiwen Luo
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Chee Chong Choo
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Avenue, Singapore, 637551, Singapore
| | - Shaojun Yuan
- College of Chemical Engineering, Sichuan University, 19 Wangjiang Road, Wuhou, Chengdu, Sichuan, China
| | - Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Avenue, Singapore, 637551, Singapore
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, A*STAR, Singapore, 138673, Singapore
- KK Research Centre, KK Women's and Children Hospital, 100 Bukit Timah Road, Singapore, 229899, Singapore
| | - Cleo Choong
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
- KK Research Centre, KK Women's and Children Hospital, 100 Bukit Timah Road, Singapore, 229899, Singapore.
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Joanne P, Kitsara M, Boitard SE, Naemetalla H, Vanneaux V, Pernot M, Larghero J, Forest P, Chen Y, Menasché P, Agbulut O. Nanofibrous clinical-grade collagen scaffolds seeded with human cardiomyocytes induces cardiac remodeling in dilated cardiomyopathy. Biomaterials 2016; 80:157-168. [DOI: 10.1016/j.biomaterials.2015.11.035] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 11/29/2015] [Indexed: 12/13/2022]
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62
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Sika Deer Antler Collagen Type I-Accelerated Osteogenesis in Bone Marrow Mesenchymal Stem Cells via the Smad Pathway. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 2016:2109204. [PMID: 27066099 PMCID: PMC4809101 DOI: 10.1155/2016/2109204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 12/06/2015] [Indexed: 11/17/2022]
Abstract
Deer antler preparations have been used to strengthen bones for centuries. It is particularly rich in collagen type I. This study aimed to unravel part of the purported bioremedial effect of Sika deer antler collagen type I (SDA-Col I) on bone marrow mesenchymal stem cells. The results suggest that SDA-Col I might be used to promote and regulate osteoblast proliferation and differentiation. SDA-Col I might potentially provide the basis for novel therapeutic strategies in the treatment of bone injury and/or in scaffolds for bone replacement strategies. Finally, isolation of SDA-Col I from deer antler represents a renewable, green, and uncomplicated way to obtain a biomedically valuable therapeutic.
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Coimplanted endothelial cells improve adipose tissue grafts' survival by increasing vascularization. J Craniofac Surg 2016; 26:358-64. [PMID: 25675023 DOI: 10.1097/scs.0000000000001470] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND With goal of improving fat graft survival, many studies have focused on supplementing cells in the graft fat. In these studies, enhanced vascularization is considered the most important mechanism for the improved graft survival. Endothelial cells (ECs) are essential in vessel formation of the vascularization. Therefore, in this study, we coimplanted ECs with adipose tissue to investigate whether the ECs can enhance graft survival in a cell concentration-dependent manner. METHODS Endothelial cells were isolated from stromal vascular fraction derived from human liposuction aspirates, and the EC characteristics were confirmed by CD31 immunofluorescence staining, measuring acetylated low-density lipoprotein uptake, and observing the formation of capillary-like tubular structures in Matrigel. During the animal experiment, the isolated ECs were labeled, then added to 0.5-mL fat grafts at different numbers (0.5 × 10(6), 1 × 10(6), 2 × 10(6), and 4 × 10(6) cells) before subcutaneous implantation in nude mice. Grafts were harvested at 1 week, 1 month, and 2 months after -transplantation, and graft survival and vascularization were evaluated based on weight measurements, histological assessment, and vascular gene expression. RESULTS Stromal vascular fraction-derived vascular cells exhibited typical EC characteristics. The observed differences in explanted graft weight, vessel density, vascular gene expression, and cell tracking result indicated that coimplantation with ECs accelerated vascularization that increased graft survival in a concentration-dependent manner. Over the experimental period, fat grafts implanted with 4 × 10(6) ECs showed no weight loss and the greatest increases in measures of vascularization. CONCLUSIONS Endothelial cells can effectively enhance vascularization in fat grafts, and higher EC concentrations (eg, 4 × 10(6) ECs/0.5 mL adipose tissue) may best support graft survival.
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Ho CC, Huang SC, Wei CK, Ding SJ. In vitro degradation and angiogenesis of the porous calcium silicate–gelatin composite scaffold. J Mater Chem B 2016; 4:505-512. [DOI: 10.1039/c5tb02401c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calcium silicate-gelatin scaffolds stimulated the release of angiogenesis factors such as von Willebrand factor and angiopoietin-1 more than the calcium silicate scaffold.
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Affiliation(s)
- Chuan-Chen Ho
- School of Dentistry
- Chung Shan Medical University
- Taichung City 402
- Taiwan
- Department of Dentistry
| | - Shu-Ching Huang
- School of Dentistry
- Chung Shan Medical University
- Taichung City 402
- Taiwan
| | - Chung-Kai Wei
- Department of Dentistry
- Chung Shan Medical University Hospital
- Taichung City 402
- Taiwan
| | - Shinn-Jyh Ding
- Department of Dentistry
- Chung Shan Medical University Hospital
- Taichung City 402
- Taiwan
- Institute of Oral Science
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Walia A, Yang JF, Huang YH, Rosenblatt MI, Chang JH, Azar DT. Endostatin's emerging roles in angiogenesis, lymphangiogenesis, disease, and clinical applications. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1850:2422-38. [PMID: 26367079 PMCID: PMC4624607 DOI: 10.1016/j.bbagen.2015.09.007] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 09/02/2015] [Accepted: 09/10/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND Angiogenesis is the process of neovascularization from pre-existing vasculature and is involved in various physiological and pathological processes. Inhibitors of angiogenesis, administered either as individual drugs or in combination with other chemotherapy, have been shown to benefit patients with various cancers. Endostatin, a 20-kDa C-terminal fragment of type XVIII collagen, is one of the most potent inhibitors of angiogenesis. SCOPE OF REVIEW We discuss the biology behind endostatin in the context of its endogenous production, the various receptors to which it binds, and the mechanisms by which it acts. We focus on its inhibitory role in angiogenesis, lymphangiogenesis, and cancer metastasis. We also present emerging clinical applications for endostatin and its potential as a therapeutic agent in the form a short peptide. MAJOR CONCLUSIONS The delicate balance between pro- and anti-angiogenic factors can be modulated to result in physiological wound healing or pathological tumor metastasis. Research in the last decade has emphasized an emerging clinical potential for endostatin as a biomarker and as a therapeutic short peptide. Moreover, elevated or depressed endostatin levels in diseased states may help explain the pathophysiological mechanisms of the particular disease. GENERAL SIGNIFICANCE Endostatin was once sought after as the 'be all and end all' for cancer treatment; however, research throughout the last decade has made it apparent that endostatin's effects are complex and involve multiple mechanisms. A better understanding of newly discovered mechanisms and clinical applications still has the potential to lead to future advances in the use of endostatin in the clinic.
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Affiliation(s)
- Amit Walia
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
| | - Jessica F Yang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
| | - Yu-Hui Huang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
| | - Mark I Rosenblatt
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
| | - Jin-Hong Chang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA.
| | - Dimitri T Azar
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
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Heinemann F, Hasan I, Bourauel C, Biffar R, Mundt T. Bone stability around dental implants: Treatment related factors. Ann Anat 2015; 199:3-8. [PMID: 25770887 DOI: 10.1016/j.aanat.2015.02.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 11/15/2022]
Abstract
The bone bed around dental implants is influenced by implant and augmentation materials, as well as the insertion technique used. The primary influencing factors include the dental implant design, augmentation technique, treatment protocol, and surgical procedure. In addition to these treatment-related factors, in the literature, local and systemic factors have been found to be related to the bone stability around implants. Bone is a dynamic organ that optimises itself depending on the loading condition above it. Bone achieves this optimisation through the remodelling process. Several studies have confirmed the importance of the implant design and direction of the applied force on the implant system. Equally dispersed strains and stresses in the physiological range should be achieved to ensure the success of an implant treatment. If a patient wishes to accelerate the treatment time, different protocols can be chosen. However, each one must consider the amount and quality of the available local bone. Immediate implantation is only successful if the primary stability of the implant can be provided from residual bone in the socket after tooth extraction. Immediate loading demands high primary stability and, sometimes, the distribution of mastication forces by splinting or even by inserting additional implants to ensure their success. Augmentation materials with various properties have been developed in recent years. In particular, resorption time and stableness affect the usefulness in different situations. Hence, treatment protocols can optimise the time for simultaneous implant placements or optimise the follow-up time for implant placement.
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Affiliation(s)
- Friedhelm Heinemann
- Department of Prosthodontics, Gerodontology and Biomaterials, University of Greifswald, Rotgerberstr. 8, 17489 Greifswald, Germany.
| | - Istabrak Hasan
- Endowed Chair of Oral Technology, Department of Prosthodontics, Preclinical Education and Dental Materials Science, University of Bonn, Welschnonnenstr. 17, 53111 Bonn, Germany; Department of Prosthodontics, Preclinical Education and Dental Materials Science, University of Bonn, Welschnonnenstr. 17, 53111 Bonn, Germany
| | - Christoph Bourauel
- Endowed Chair of Oral Technology, Department of Prosthodontics, Preclinical Education and Dental Materials Science, University of Bonn, Welschnonnenstr. 17, 53111 Bonn, Germany
| | - Reiner Biffar
- Department of Prosthodontics, Gerodontology and Biomaterials, University of Greifswald, Rotgerberstr. 8, 17489 Greifswald, Germany
| | - Torsten Mundt
- Department of Prosthodontics, Gerodontology and Biomaterials, University of Greifswald, Rotgerberstr. 8, 17489 Greifswald, Germany
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Lee EU, Lim HC, Hong JY, Lee JS, Jung UW, Choi SH. Bone regenerative efficacy of biphasic calcium phosphate collagen composite as a carrier of rhBMP-2. Clin Oral Implants Res 2015; 27:e91-e99. [PMID: 25675839 DOI: 10.1111/clr.12568] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2015] [Indexed: 01/12/2023]
Abstract
OBJECTIVES This study compared the bone regenerative effects of a recombinant human bone morphogenetic protein 2 (rhBMP-2)-loaded collagen-based biphasic calcium phosphate composite (BCPC) and rhBMP-2-loaded biphasic calcium phosphate (BCP). MATERIAL AND METHODS The in vitro release profiles of rhBMP-2-loaded BCP and BCPC were measured. The animal surgery was performed on ten rabbits. Four 8-mm-diameter circular calvarial defects were made and filled with BCP, BCPC, rhBMP-2-loaded BCP (BMP + BCP) and rhBMP-2-loaded BCPC (BMP + BCPC). The animals were euthanized either 2 or 8 weeks after surgery. RESULTS The initial burst release of rhBMP-2 was greater for BCP than for BCPC, and both presented a slow release pattern thereafter. In rabbit calvarial defects, the space maintaining capability and graft resorption of all experimental groups did not show statistical differences at 2 and 8 weeks. New bone formation in the rhBMP-2-loaded groups was greater than in the non-loaded groups at both weeks, but the amount of new bone was comparable between both rhBMP-2-loaded groups at both weeks. There was a distinct histologic difference between the BMP + BCP and BMP + BCPC groups at 2 weeks; the new bone formation occurred more in the intergranular spaces and the BCP-to-bone contact was greater in the BMP + BCPC group, but these differences were no longer discernible at 8 weeks. CONCLUSIONS BCP- and BCPC-loaded rhBMP-2 significantly improved bone regeneration and BCPC led to a dense network of new bone and bone particles during the early healing period. BCPC can therefore be considered as a promising candidate for carrying rhBMP-2.
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Affiliation(s)
- Eun-Ung Lee
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea
| | - Hyun-Chang Lim
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea
| | - Ji-Youn Hong
- Department of Periodontology, School of Dentistry, Kyung Hee University, Seoul, Korea
| | - Jung-Seok Lee
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea
| | - Ui-Won Jung
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea
| | - Seong-Ho Choi
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, Seoul, Korea.
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Lee EU, Kim DJ, Lim HC, Lee JS, Jung UW, Choi SH. Comparative evaluation of biphasic calcium phosphate and biphasic calcium phosphate collagen composite on osteoconductive potency in rabbit calvarial defect. Biomater Res 2015; 19:1. [PMID: 26331072 PMCID: PMC4552310 DOI: 10.1186/s40824-014-0026-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 12/29/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aim of this study was to determine the osteoconductivity of biphasic calcium phosphate collagen composite (BCPC) in rabbit calvarial defect model by comparing with biphasic calcium phosphate (BCP). Four 8 mm diameter bicortical calvarial defects were made in ten rabbits. Each of the defects was randomly assigned and filled with 1) collagen sponge, 2) BCP, 3) BCPC, and 4) nothing as control. The animals were sacrificed at either 2 weeks (n = 5) or 8 weeks (n = 5) healing period. RESULTS All groups showed wedge shaped new bone formation limited to the area of the defect margin at both healing periods. The amounts of new bone and defect closure were similar among all groups. In the control and collagen sponge group, the center of the defect was depressed by surrounding tissues. In contrast, in BCP and BCPC group, the center of the defect did not depressed and the grafted materials maintained the space. And the augmented area was significantly higher in BCP and BCPC group compared to the control and collagen sponge group at both healing periods (p < 0.05). CONCLUSIONS The BCPC and BCP demonstrated proper space maintaining capacity and osteoconductive property, suggesting BCPC can be efficiently utilized in various clinical situations.
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Affiliation(s)
- Eun-Ung Lee
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
| | - Dong-Ju Kim
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
| | - Hyun-Chang Lim
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
| | - Jung-Seok Lee
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
| | - Ui-Won Jung
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
| | - Seong-Ho Choi
- Department of Periodontology, Research Institute for Periodontal Regeneration, College of Dentistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul South Korea
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Järveläinen H, Sainio A, Wight TN. Pivotal role for decorin in angiogenesis. Matrix Biol 2015; 43:15-26. [PMID: 25661523 DOI: 10.1016/j.matbio.2015.01.023] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 01/29/2015] [Accepted: 01/29/2015] [Indexed: 01/05/2023]
Abstract
Angiogenesis, the formation of new blood vessels from preexisting vessels, is a highly complex process. It is regulated in a finely-tuned manner by numerous molecules including not only soluble growth factors such as vascular endothelial growth factor and several other growth factors, but also a diverse set of insoluble molecules, particularly collagenous and non-collagenous matrix constituents. In this review we have focused on the role and potential mechanisms of a multifunctional small leucine-rich proteoglycan decorin in angiogenesis. Depending on the cellular and molecular microenvironment where angiogenesis occurs, decorin can exhibit either a proangiogenic or an antiangiogenic activity. Nevertheless, in tumorigenesis-associated angiogenesis and in various inflammatory processes, particularly foreign body reactions and scarring, decorin exhibits an antiangiogenic activity, thus providing a potential basis for the development of decorin-based therapies in these pathological situations.
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Affiliation(s)
- Hannu Järveläinen
- Department of Medical Biochemistry and Genetics, University of Turku, Turku, Finland; Department of Medicine, Division of Endocrinology, Turku University Hospital, Turku, Finland.
| | - Annele Sainio
- Department of Medical Biochemistry and Genetics, University of Turku, Turku, Finland
| | - Thomas N Wight
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA
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Harkness LM, Ashton AW, Burgess JK. Asthma is not only an airway disease, but also a vascular disease. Pharmacol Ther 2014; 148:17-33. [PMID: 25460035 DOI: 10.1016/j.pharmthera.2014.11.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 07/29/2014] [Indexed: 12/24/2022]
Abstract
Multiple studies have identified an expansion and morphological dysregulation of the bronchial vascular network in the airways of asthmatics. Increased number, size and density of blood vessels, as well as vascular leakage and plasma engorgement, have been reported in the airways of patients with all grades of asthma from mild to fatal. This neovascularisation is an increasingly commonly reported feature of airway remodelling; however, the pathophysiological impact of the increased vasculature in the bronchial wall and its significance to pulmonary function in asthma are unrecognised at this time. Multiple factors capable of influencing the development and persistence of the vascular network exist within asthmatic airway tissue. These include structural components of the altered extracellular matrix (ECM), imbalance of proteases and their endogenous inhibitors, release of active matrikines and the dysregulated levels of both soluble and matrix sequestered growth factors. This review will explore the features of the asthmatic airway which influence the development and persistence of the increased vascular network, as well as the effect of enhanced tissue perfusion on chronic inflammation and airway dynamics. The response of cells of the airways to the altered vascular profile and the subsequent influence on the features of airway remodelling will also be highlighted. We will explore the failure of current asthma therapeutics in "normalising" this vascular remodelling. Finally, we will summarize the outcomes of recent clinical trials which provide hope that anti-angiogenic therapies may be a potent asthma-resolving class of drugs and provide a new approach to asthma management in the future.
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Affiliation(s)
- Louise M Harkness
- Respiratory Cellular and Molecular Biology, Woolcock Institute of Medical Research, The University of Sydney, Sydney, NSW, Australia; Discipline of Pharmacology, The University of Sydney, Sydney, NSW, Australia
| | - Anthony W Ashton
- Division of Perinatal Research, Kolling Institute, Sydney, NSW, Australia
| | - Janette K Burgess
- Respiratory Cellular and Molecular Biology, Woolcock Institute of Medical Research, The University of Sydney, Sydney, NSW, Australia; Discipline of Pharmacology, The University of Sydney, Sydney, NSW, Australia.
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71
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Kunert-Keil C, Gredes T, Heinemann F, Dominiak M, Botzenhart U, Gedrange T. Socket augmentation using a commercial collagen-based product--an animal study in pigs. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 46:177-83. [PMID: 25491974 DOI: 10.1016/j.msec.2014.10.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/25/2014] [Accepted: 10/08/2014] [Indexed: 10/24/2022]
Abstract
The aim of the present study was to identify properties of pure collagen for augmentation techniques and compare to a proved xenogenic material and natural bone regeneration. For that the osteogenesis of extraction alveoli after augmentation with a collagen cone covered with an absorbable collagen membrane in a single product (PARASORB Sombrero®, Resorba) was evaluated in a pig model. Extraction alveoli were treated with the collagen cone and the collagen membrane in a single product (test group; n=7) or demineralized bovine bone mineral and a collagen membrane (two separate products; positive control; n=7). Untreated alveoli were used (n=6) as negative controls.(1) Bone specimens were extracted 1 and 3 months after teeth extraction. Serial longitudinal sections were stained with Masson Goldner trichrome. Furthermore, bone specimens were examined using X-ray analyses. Significant differences of bone atrophy were detected 12 weeks after material insertion using X-ray analyses. The bone atrophy was reduced by approximately 32% after insertion of the positive control (P=0.046). Bone atrophy reached 37.6% of those from untreated alveoli (P=0.002) using the test group. After 4 weeks, bone formation was noticeable in most sites, whereas after 12 weeks of healing, specimens of all groups exhibited nearly complete osseous organization of the former defected area. The mandibulary bone texture showed typical spongious bone structures. Histomorphometric analyses revealed after 4 and 12 weeks significant higher levels of bone marrow in test and negative control than in positive control. Quantification of bone tissue and osteoid does not show any significant difference. The present study confirms reduced bone resorption following socket augmentation with an absorbable collagen membrane with collagen cone while the resulting bone structure is similar to natural bone regeneration. Pure collagen can be used for bone augmentation, and shows over other xenogenic materials, a clear advantage with respect to the bone density and structure.
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Affiliation(s)
- Christiane Kunert-Keil
- Department of Orthodontics, Carl Gustav Carus Campus, Technische Universität Dresden, Fetscherstr. 74, D-01307 Dresden, Germany.
| | - Tomasz Gredes
- Department of Orthodontics, Carl Gustav Carus Campus, Technische Universität Dresden, Fetscherstr. 74, D-01307 Dresden, Germany.
| | - Friedhelm Heinemann
- Department of Prosthodontics, Gerodontology and Biomaterials, Medical University of Greifswald, Rotgerberstr. 8, D-17487 Greifswald, Germany.
| | - Marzena Dominiak
- Department of Dental Surgery, Silesian Piast Medical University, 26 Krakowska st, 50-424 Wroclaw, Poland.
| | - Ute Botzenhart
- Department of Orthodontics, Carl Gustav Carus Campus, Technische Universität Dresden, Fetscherstr. 74, D-01307 Dresden, Germany.
| | - Tomasz Gedrange
- Department of Orthodontics, Carl Gustav Carus Campus, Technische Universität Dresden, Fetscherstr. 74, D-01307 Dresden, Germany.
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Endoglin mediates fibronectin/α5β1 integrin and TGF-β pathway crosstalk in endothelial cells. EMBO J 2012; 31:3885-900. [PMID: 22940691 DOI: 10.1038/emboj.2012.246] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 08/07/2012] [Indexed: 11/08/2022] Open
Abstract
Both the transforming growth factor β (TGF-β) and integrin signalling pathways have well-established roles in angiogenesis. However, how these pathways integrate to regulate angiogenesis is unknown. Here, we show that the extracellular matrix component, fibronectin, and its cellular receptor, α5β1 integrin, specifically increase TGF-β1- and BMP-9-induced Smad1/5/8 phosphorylation via the TGF-β superfamily receptors endoglin and activin-like kinase-1 (ALK1). Fibronectin and α5β1 integrin increase Smad1/5/8 signalling by promoting endoglin/ALK1 cell surface complex formation. In a reciprocal manner, TGF-β1 activates α5β1 integrin and downstream signalling to focal adhesion kinase (FAK) in an endoglin-dependent manner. α5β1 integrin and endoglin form a complex on the cell surface and co-internalize, with their internalization regulating α5β1 integrin activation and signalling. Functionally, endoglin-mediated fibronectin/α5β1 integrin and TGF-β pathway crosstalk alter the responses of endothelial cells to TGF-β1, switching TGF-β1 from a promoter to a suppressor of migration, inhibiting TGF-β1-mediated apoptosis to promote capillary stability, and partially mediating developmental angiogenesis in vivo. These studies provide a novel mechanism for the regulation of TGF-β superfamily signalling and endothelial function through crosstalk with integrin signalling pathways.
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Shin S, Wolgamott L, Yoon SO. Regulation of endothelial cell morphogenesis by the protein kinase D (PKD)/glycogen synthase kinase 3 (GSK3)β pathway. Am J Physiol Cell Physiol 2012; 303:C743-56. [PMID: 22855295 DOI: 10.1152/ajpcell.00442.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular morphogenesis is a key process for development, reproduction, and pathogenesis. Thus understanding the mechanisms of this process is of pathophysiological importance. Despite the fact that collagen I is the most abundant and potent promorphogenic molecule known, the molecular mechanisms by which this protein regulates endothelial cell tube morphogenesis are still unclear. Here we provide strong evidence that collagen I induces tube morphogenesis by inhibiting glycogen synthase kinase 3β (GSK3β). Further mechanistic studies revealed that GSK3β activity is regulated by protein kinase D (PKD). PKD inhibited GSK3β activity, which was required for collagen I-induced endothelial tube morphogenesis. We also found that GSK3β regulated trafficking of integrin α(2)β(1) in a Rab11-dependent manner. Taken together, our studies highlight the important role of PKD in the regulation of collagen I-induced vascular morphogenesis and show that it is mediated by the modulation of GSK3β activity and integrin α(2)β(1) trafficking.
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Affiliation(s)
- Sejeong Shin
- Dept. of Cancer and Cell Biology, Univ. of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
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Bertassoni LE, Orgel JPR, Antipova O, Swain MV. The dentin organic matrix - limitations of restorative dentistry hidden on the nanometer scale. Acta Biomater 2012; 8:2419-33. [PMID: 22414619 PMCID: PMC3473357 DOI: 10.1016/j.actbio.2012.02.022] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/16/2012] [Accepted: 02/28/2012] [Indexed: 11/28/2022]
Abstract
The prevention and treatment of dental caries are major challenges occurring in dentistry. The foundations for modern management of this dental disease, estimated to affect 90% of adults in Western countries, rest upon the dependence of ultrafine interactions between synthetic polymeric biomaterials and nanostructured supramolecular assemblies that compose the tooth organic substrate. Research has shown, however, that this interaction imposes less than desirable long-term prospects for current resin-based dental restorations. Here we review progress in the identification of the nanostructural organization of the organic matrix of dentin, the largest component of the tooth structure, and highlight aspects relevant to understating the interaction of restorative biomaterials with the dentin substrate. We offer novel insights into the influence of the hierarchically assembled supramolecular structure of dentin collagen fibrils and their structural dependence on water molecules. Secondly, we review recent evidence for the participation of proteoglycans in composing the dentin organic network. Finally, we discuss the relation of these complexly assembled nanostructures with the protease degradative processes driving the low durability of current resin-based dental restorations. We argue in favour of the structural limitations that these complexly organized and inherently hydrated organic structures may impose on the clinical prospects of current hydrophobic and hydrolyzable dental polymers that establish ultrafine contact with the tooth substrate.
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Affiliation(s)
- Luiz E Bertassoni
- Biomaterials Science Research Unit, Faculty of Dentistry, University of Sydney, United Dental Hospital, NSW, Australia.
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Peng YJ, Pan CY, Hsieh YT, Wu S, Chu HN, Hsu WC. The application of tissue engineering in reversing mitomycin C-induced ischemic conjunctiva. J Biomed Mater Res A 2012; 100:1126-35. [DOI: 10.1002/jbm.a.34041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 12/01/2011] [Indexed: 11/08/2022]
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Abstract
OBJECTIVE The objective of the study was to inform wound care practitioners of mesenchymal stem cell application for nonhealing wounds. Recent advances in delivery systems are also discussed in order to highlight potential improvements toward clinical application of stem cell therapy for chronic wounds. DATA SOURCES MEDLINE and PubMed Central were searched for scientific studies regarding the use of mesenchymal stem cells and delivery systems in wound healing. STUDY SELECTION Preclinical studies using stem cells as therapeutic modality for chronic wounds were selected for this review. DATA EXTRACTION Information on study design, sample size and characteristics, stem cell source, type of delivery systems, and rate and time of wound closure was abstracted. DATA SYNTHESIS Application of mesenchymal stem cells improved wound healing in experimental and clinical settings. Advances in stem cell therapy and delivery vehicles offer promising alternatives to current limited therapeutic modalities for chronic wounds. CONCLUSIONS Stem cell therapy has recently emerged as a promising therapeutic strategy for nonhealing wounds. Further research is needed to evaluate the relationship between the various delivery systems and stem cells in order to maximize their therapeutic effects. Development of novel delivery vehicles for stem cells can open new opportunities for more effective cell therapy of chronic wounds.
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Bone level change of extraction sockets with Bio-Oss collagen and implant placement: a clinical study. Ann Anat 2011; 194:508-12. [PMID: 22244384 DOI: 10.1016/j.aanat.2011.11.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 11/19/2011] [Accepted: 11/24/2011] [Indexed: 11/23/2022]
Abstract
AIMS To compare the reaction of the alveolar bone to the preservation of the extraction socket by Bio-Oss Collagen with and without combination of implant treatment. To evaluate whether early implant insertion 8-10weeks thereafter could be a suitable time point for long term bone stability around the implant. METHODS A total of 25 patients were divided into three groups: The first group (seven patients) received Bio-Oss Collagen after extraction and 8-10weeks later an implant, the second group (eight patients) received only Bio-Oss Collagen without implantation thereafter, while the third group was considered as a control (eleven patients), where the sockets healed without any treatment. The change in the vertical bone level of the alveolar crests were measured from panoramic radiographs and statistically analysed. RESULTS Bone level change was significantly less for Group 1 than Group 3 (P<0.001), while was not significantly different for Group 2 and Group 3 (P=0.23). However, the rate of bone level change per year was statistically smaller for Group 1 compared to Group 3 (P=0.019) and as well as for Group 1 than for Group 2 (P=0.003), whereas the change per year was not significantly different for Group 2 vs. Group 3 (P=0.122). CONCLUSION Bone level preservation of extraction sockets using Bio-Oss Collagen with implantation is significantly better compared to using Bio-Oss Collagen only and untreated sockets. Implant insertion 8-10weeks after extraction is a suitable time point after socket augmentation.
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Orgel J, Antipova O, Sagi I, Bitler A, Qiu D, Wang R, Xu Y, San Antonio J. Collagen fibril surface displays a constellation of sites capable of promoting fibril assembly, stability, and hemostasis. Connect Tissue Res 2011; 52:18-24. [PMID: 21117898 PMCID: PMC3244825 DOI: 10.3109/03008207.2010.511354] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Fibrillar collagens form the structural basis of organs and tissues including the vasculature, bone, and tendon. They are also dynamic, organizational scaffolds that present binding and recognition sites for ligands, cells, and platelets. We interpret recently published X-ray diffraction findings and use atomic force microscopy data to illustrate the significance of new insights into the functional organization of the collagen fibril. These data indicate that collagen's most crucial functional domains localize primarily to the overlap region, comprising a constellation of sites we call the "master control region." Moreover, the collagen's most exposed aspect contains its most stable part-the C-terminal region that controls collagen assembly, cross-linking, and blood clotting. Hidden beneath the fibril surface exists a constellation of "cryptic" sequences poised to promote hemostasis and cell-collagen interactions in tissue injury and regeneration. These findings begin to address several important, and previously unresolved, questions: How functional domains are organized in the fibril, which domains are accessible, and which require proteolysis or structural trauma to become exposed? Here we speculate as to how collagen fibrillar organization impacts molecular processes relating to tissue growth, development, and repair.
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Affiliation(s)
- J.P.R.O Orgel
- Pritzker Institute of Biomedical Science and Engineering, Illinois Institute of Technology, Chicago, IL, USA.,Department of Biological, Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL, USA.,Corresponding Authors: J.P.R.O. Orgel () and J.D. San Antonio ()
| | - O. Antipova
- Pritzker Institute of Biomedical Science and Engineering, Illinois Institute of Technology, Chicago, IL, USA.,Department of Biological, Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL, USA
| | - I Sagi
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - A. Bitler
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - D. Qiu
- Department of Biological, Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL, USA
| | - R. Wang
- Department of Biological, Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL, USA
| | - Y. Xu
- Department of Chemistry, Hunter College, CUNY, NY, USA
| | - J.D. San Antonio
- Operations, Orthovita, Inc., Malvern, PA, USA.,Corresponding Authors: J.P.R.O. Orgel () and J.D. San Antonio ()
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79
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Orgel JPRO, San Antonio JD, Antipova O. Molecular and structural mapping of collagen fibril interactions. Connect Tissue Res 2011; 52:2-17. [PMID: 21182410 DOI: 10.3109/03008207.2010.511353] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The fibrous collagens form the structural basis of all mammalian connective tissues, including the vasculature, dermis, bones, tendons, cartilage, and those tissues that support organs such as the heart, kidneys, liver, and lungs. The helical structure of collagen has been extensively studied but in addition to its helical character, its molecular packing arrangement (in its aggregated or fibrillar form) and the presence of specific amino acid sequences govern collagen's in vivo functions. Collagen's molecular packing arrangement helps control cellular communication, attachment and movement, and conveys its tissue-specific biomechanical properties. Recent progress in understanding collagen's molecular packing, fibrillar structure, domain organization, and extracellular matrix (ECM) interactions in light of X-ray fiber diffraction data provides significant new insights into how the ECM is organized and functions. In this review, the hierarchy of fibrillar collagen structure is discussed in the context of how this organization affects ECM-"ligand" interactions, with specific attention to collagenolysis, integrins, fibronection, glycoprotein VI receptor (GPVI), and proteoglycans (PG). Understanding the complex structure of collagen and its attached ligands should provide new insights into tissue growth, development, regeneration, and disease.
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Affiliation(s)
- J P R O Orgel
- Pritzker Institute of Biomedical Science and Engineering, Illinois Institute of Technology, Chicago, IL 60616, USA.
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80
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Habibovic P, Bassett DC, Doillon CJ, Gerard C, McKee MD, Barralet JE. Collagen biomineralization in vivo by sustained release of inorganic phosphate ions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:1858-1862. [PMID: 20512962 DOI: 10.1002/adma.200902778] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- Pamela Habibovic
- Faculty of Dentistry, McGill University, Montreal, Quebec H3A 2B2, Canada
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81
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Petri AL, Simonsen AH, Høgdall E, Christensen IJ, Kjaer SK, Yip C, Risum S, Pedersen AT, Hartwell D, Fung ET, Høgdall C. Comparison of proteomic biomarker panels in urine and serum for ovarian cancer diagnosis. Proteomics Clin Appl 2010; 4:304-14. [DOI: 10.1002/prca.200900042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Revised: 09/29/2009] [Accepted: 10/21/2009] [Indexed: 11/07/2022]
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82
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Böttcher-Haberzeth S, Biedermann T, Reichmann E. Tissue engineering of skin. Burns 2009; 36:450-60. [PMID: 20022702 DOI: 10.1016/j.burns.2009.08.016] [Citation(s) in RCA: 211] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 08/14/2009] [Indexed: 01/27/2023]
Abstract
The engineering of skin substitutes and their application on human patients has become a reality. However, cell biologists, biochemists, technical engineers, and surgeons are still struggling with the generation of complex skin substitutes that can readily be transplanted in large quantities, possibly in only one surgical intervention and without significant scarring. Constructing a dermo-epidermal substitute that rapidly vascularizes, optimally supports a stratifying epidermal graft on a biodegradable matrix, and that can be conveniently handled by the surgeon, is now the ambitious goal. After all, this goal has to be reached coping with strict safety requirements and the harsh rules of the economic market.
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Affiliation(s)
- Sophie Böttcher-Haberzeth
- Tissue Biology Research Unit, Department of Surgery, University Children's Hospital Zurich, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland
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83
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Orgel JPRO, Eid A, Antipova O, Bella J, Scott JE. Decorin core protein (decoron) shape complements collagen fibril surface structure and mediates its binding. PLoS One 2009; 4:e7028. [PMID: 19753304 PMCID: PMC2737631 DOI: 10.1371/journal.pone.0007028] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Accepted: 08/19/2009] [Indexed: 11/18/2022] Open
Abstract
Decorin is the archetypal small leucine rich repeat proteoglycan of the vertebrate extracellular matrix (ECM). With its glycosaminoglycuronan chain, it is responsible for stabilizing inter-fibrillar organization. Type I collagen is the predominant member of the fibrillar collagen family, fulfilling both organizational and structural roles in animal ECMs. In this study, interactions between decoron (the decorin core protein) and binding sites in the d and e1 bands of the type I collagen fibril were investigated through molecular modeling of their respective X-ray diffraction structures. Previously, it was proposed that a model-based, highly curved concave decoron interacts with a single collagen molecule, which would form extensive van der Waals contacts and give rise to strong non-specific binding. However, the large well-ordered aggregate that is the collagen fibril places significant restraints on modes of ligand binding and necessitates multi-collagen molecular contacts. We present here a relatively high-resolution model of the decoron-fibril collagen complex. We find that the respective crystal structures complement each other well, although it is the monomeric form of decoron that shows the most appropriate shape complementarity with the fibril surface and favorable calculated energies of interaction. One molecule of decoron interacts with four to six collagen molecules, and the binding specificity relies on a large number of hydrogen bonds and electrostatic interactions, primarily with the collagen motifs KXGDRGE and AKGDRGE (d and e1 bands). This work helps us to understand collagen-decorin interactions and the molecular architecture of the fibrillar ECM in health and disease.
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Affiliation(s)
- Joseph P R O Orgel
- BioCAT and microCoSM Centres: Pritzker Institute of Biomedical Science and Engineering, Illinois Institute of Technology, Chicago, Illinois, USA.
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84
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Chen X, Aledia AS, Ghajar CM, Griffith CK, Putnam AJ, Hughes CCW, George SC. Prevascularization of a fibrin-based tissue construct accelerates the formation of functional anastomosis with host vasculature. Tissue Eng Part A 2009; 15:1363-71. [PMID: 18976155 DOI: 10.1089/ten.tea.2008.0314] [Citation(s) in RCA: 228] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
One critical obstacle facing tissue engineering is the formation of functional vascular networks that can support tissue survival in vivo. We hypothesized that prevascularizing a tissue construct with networks of well-formed capillaries would accelerate functional anastomosis with the host upon implantation. Fibrin-based tissues were prevascularized with capillary networks by coculturing human umbilical vein endothelial cells (HUVECs) and fibroblasts in fibrin gels for 1 week. The prevascularized tissue and nonprevascularized controls were implanted subcutaneously onto the dorsal surface of immune-deficient mice and retrieved at days 3, 5, 7 and 14. HUVEC-lined vessels containing red blood cells were evident in the prevascularized tissue by day 5, significantly earlier than nonprevascularized tissues (14 days). Analysis of the HUVEC-lined vessels demonstrated that the number and area of perfused lumens in the prevascularized tissue were significantly larger compared to controls. In addition, collagen deposition and a larger number of proliferating cells were evident in the prevascularized tissue at day 14. Our results demonstrate that prevascularizing a fibrin-based tissue with well-formed capillaries accelerates anastomosis with the host vasculature, and promotes cellular activity consistent with tissue remodeling. Our prevascularization strategy may be useful to design large three-dimensional engineered tissues.
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Affiliation(s)
- Xiaofang Chen
- Department of Biomedical Engineering, University of California Irvine, Irvine, California 92697-2715, USA
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85
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Dobner S, Bezuidenhout D, Govender P, Zilla P, Davies N. A synthetic non-degradable polyethylene glycol hydrogel retards adverse post-infarct left ventricular remodeling. J Card Fail 2009; 15:629-36. [PMID: 19700140 DOI: 10.1016/j.cardfail.2009.03.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Revised: 03/13/2009] [Accepted: 03/17/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Left ventricular remodeling after myocardial infarction is a key component of heart failure and it has long been postulated that it may result from increased wall stress. It has recently been suggested that an injectable, non-degradable polymer may limit pathological remodeling in a manner analogous to that of cardiac support devices. We have tested a non-degradable polyethylene glycol (PEG) gel in a rat infarction model. METHODS AND RESULTS After permanent ligation of the left anterior descending artery in male Wistar rats, PEG gel reagents were injected into the infarcted region and polymerized in situ. At 4 weeks, fractional shortening and infarct volume were unchanged relative to a saline injected control, but the infarct-induced left ventricular end-diastolic diameter (LVEDD) increase was substantially reduced (43%, P < .05) and wall thinning was completely prevented. At 13 weeks, the LVEDD were similar for both saline- and PEG-injected hearts. The non-degradable PEG gels did elicit a macrophage-based inflammatory reaction. CONCLUSIONS The injection of non-degradable synthetic gel was effective in ameliorating pathological remodeling in the immediate postinfarction healing phase, but was unable to prevent the dilation that occurred at later stages in the healed heart.
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Affiliation(s)
- Stephan Dobner
- Cardiovascular Research Unit, Chris Barnard Division of Cardiothoracic Surgery, University of Cape Town Department of Health Sciences, Cape Town, South Africa
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