scholarly journals Composite Membranes of Poly(ε-caprolactone) with Bisphosphonate-Loaded Bioactive Glasses for Potential Bone Tissue Engineering Applications

Molecules ◽  
2019 ◽  
Vol 24 (17) ◽  
pp. 3067 ◽  
Author(s):  
Zoi Terzopoulou ◽  
Diana Baciu ◽  
Eleni Gounari ◽  
Theodore Steriotis ◽  
Georgia Charalambopoulou ◽  
...  

Poly(ε-caprolactone) (PCL) is a bioresorbable synthetic polyester with numerous biomedical applications. PCL membranes show great potential in guided tissue regeneration because they are biocompatible, occlusive and space maintaining, but lack osteoconductivity. Therefore, two different types of mesoporous bioactive glasses (SiO2-CaO-P2O5 and SiO2-SrO-P2O5) were synthesized and incorporated in PCL thin membranes by spin coating. To enhance the osteogenic effect of resulting membranes, the bioglasses were loaded with the bisphosphonate drug ibandronate prior to their incorporation in the polymeric matrix. The effect of the composition of the bioglasses as well as the presence of absorbed ibandronate on the physicochemical, cell attachment and differentiation properties of the PCL membranes was evaluated. Both fillers led to a decrease of the crystallinity of PCL, along with an increase in its hydrophilicity and a noticeable increase in its bioactivity. Bioactivity was further increased in the presence of a Sr substituted bioglass loaded with ibandronate. The membranes exhibited excellent biocompatibility upon estimation of their cytotoxicity on Wharton’s Jelly Mesenchymal Stromal Cells (WJ-SCs), while they presented higher osteogenic potential in comparison with neat PCL after WJ-SCs induced differentiation towards bone cells, which was enhanced by a possible synergistic effect of Sr and ibandronate.

2021 ◽  
pp. 088391152199784
Author(s):  
Nipun Jain ◽  
Shashi Singh

Development of an artificial tissue by tissue engineering is witnessed to be one of the long lasting clarified solutions for the damaged tissue function restoration. To accomplish this, a scaffold is designed as a cell carrier in which the extracellular matrix (ECM) performs a prominent task of controlling the inoculated cell’s destiny. ECM composition, topography and mechanical properties lead to different types of interactions between cells and ECM components that trigger an assortment of cellular reactions via diverse sensing mechanisms and downstream signaling pathways. The polysaccharides in the form of proteoglycans and glycoproteins yield better outcomes when included in the designed matrices. Glycosaminoglycan (GAG) chains present on proteoglycans show a wide range of operations such as sequestering of critical effector morphogens which encourage proficient nutrient contribution toward the growing stem cells for their development and endurance. In this review we discuss how the glycosylation aspects are of considerable importance in everyday housekeeping functions of a cell especially when placed in a controlled environment under ideal growth conditions. Hydrogels made from these GAG chains have been used extensively as a resorbable material that mimics the natural ECM functions for an efficient control over cell attachment, permeability, viability, proliferation, and differentiation processes. Also the incorporation of non-mammalian polysaccharides can elicit specific receptor responses which authorize the creation of numerous vigorous frameworks while prolonging the low cost and immunogenicity of the substance.


2021 ◽  
Author(s):  
Jessica Fayne ◽  
Huilin Huang ◽  
Mike Fischella ◽  
Yufei Liu ◽  
Zhaoxin Ban ◽  
...  

<p>Extreme precipitation, a critical factor in flooding, has selectively increased with warmer temperatures in the Western U.S. Despite this, the streamflow measurements have captured no noticeable increase in large-scale flood frequency or intensity. As flood studies have mostly focused on specific flood events in particular areas, analyses of large-scale floods and their changes have been scarce. For floods during 1960-2013, we identify six flood generating mechanisms (FGMs) that are prominent across the Western U.S., including atmospheric rivers and non-atmospheric rivers, monsoons, convective storms, radiation-driven snowmelt, and rain-on-snow, in order to identify to what extent different types of floods are changing based on the dominant FGM. The inconsistency between extreme precipitation and lack of flood increase suggests that the impact of climate change on flood risk has been modulated by hydro-meteorological and physiographic processes such as sharp increases in temperature that drive increased evapotranspiration and decreased soil moisture. Our results emphasize the importance of FGMs in understanding the complex interactions of flooding and climatic changes and explain the broad spatiotemporal changes that have occurred across the vast Western U.S. for the past 50 years.</p>


2011 ◽  
Vol 90 (12) ◽  
pp. 1428-1433 ◽  
Author(s):  
R.J. Miron ◽  
E. Hedbom ◽  
N. Saulacic ◽  
Y. Zhang ◽  
A. Sculean ◽  
...  

The osteogenic potential of autogenous bone grafts is superior to that of allografts and xenografts because of their ability to release osteoinductive growth factors and provide a natural osteoconductive surface for cell attachment and growth. In this in vitro study, autogenous bone particles were harvested by four commonly used techniques and compared for their ability to promote an osteogenic response. Primary osteoblasts were isolated and seeded on autogenous bone grafts prepared from the mandibles of miniature pigs with a bone mill, piezo-surgery, bone scraper, and bone drill (bone slurry). The osteoblast cultures were compared for their ability to promote cell attachment, proliferation, and differentiation. After 4 and 8 hrs, significantly higher cell numbers were associated with bone mill and bone scraper samples compared with those acquired by bone slurry and piezo-surgery. Similar patterns were consistently observed up to 5 days. Furthermore, osteoblasts seeded on bone mill and scraper samples expressed significantly elevated mRNA levels of collagen, osteocalcin, and osterix at 3 and 14 days and produced more mineralized tissue as assessed by alizarin red staining. These results suggest that the larger bone graft particles produced by bone mill and bone scraper techniques have a higher osteogenic potential than bone slurry and piezo-surgery.


1987 ◽  
Author(s):  
R Adany ◽  
A Kiss ◽  
J Kappelmayer ◽  
R J Ablin ◽  
L Muszbek

In addition to plasma the presence of subunit a of blood coagulation Factor XIII (FXIIl) has been verified in platelets and megakariocytes. Most recently, we demonstrated that human peripheral blood monocytes also contain FXIII subunit a. The present study was designed 1/ to determine the stage in the maturation sequence of bone marrow monocytopoesis in which FXIII appears 2/ to establish if FXIII is retained during differentiation into macrophages 3/ to assess how general is the presence of FXIII subunit a in different types of macrophages. FXIII subunit a was immunomorphologically detected in bone marrow smears, in cytospin preparations of cells from serous cavities (pleural, peritoneal, pericardial and synovial spaces), and paraformaldehyde-fixed paraffin-embedded or frozen sections of different organs where classical types of macrophages have been described earlier (liver, lung, thymus, skin, connective tissue, prostate and developing bone) . Cells containing FXIII subunit a were intensively characterized by immunofluorescent and enzymecytochemical techniques in double and treble labeling systems. Its presence was clearly demonstrated in promonocytes of bone marrow, and in all probability, it is present in monoblasts, as well. FXIII was also found in macrophages from different serous cavities and in embryonic osteoclasts. Cells containing FXIII subunit a of connective tissue were found to be tissue histiocytes, and not fibroblasts as previously thought. Kupffer cells of the liver and Langerhans cells of the epidermis were negative supporting theories that these cells are not members of monocyte-derived macrophage cell population. Immunomorphological detection of FXIII subunit a seems to be a useful marker for labeling the continuum of monocyte/macrophage cell line from the earliest ftrais in the bone marrow to the mature forms of macrophages and might be a valuable tool in the cytological diagnosis of malignant disorders of this cell line.


2007 ◽  
Vol 361-363 ◽  
pp. 1067-1070 ◽  
Author(s):  
Asako Matsushima ◽  
Noriko Kotobuki ◽  
Mika Tadokoro ◽  
Hajime Ohgushi

Hydroxyapatite (HA) ceramics together with various kinds of osteogenic cells have been used in bone tissue engineering. It is well known that the ceramics structure and composition affect cell proliferation / differentiation. In this study, three different types of HA ceramics were used to investigate initial cell attachment followed by osteoblastic differentiation of human mesenchymal stromal cells (MSCs). The results indicated that micro-pore affected the cell attachment and porosity (pore diameter and inter-pore connection) was the key to allow spacious distribution of the viable cells in the ceramics. This study also confirmed that surface pore areas of HA ceramics support the differentiation of human MSCs and thus the ceramics have the capability to regenerate damaged bone tissue.


2020 ◽  
Vol 8 (4) ◽  
pp. 127
Author(s):  
Susanne Staehlke ◽  
Armin Springer ◽  
Thomas Freitag ◽  
Jakob Brief ◽  
J. Barbara Nebe

The high biocompatibility, good mechanical properties, and perfect esthetics of ceramic dental materials motivate investigation into their suitability as an endosseous implant. Osseointegration at the interface between bone and implant surface, which is a criterion for dental implant success, is dependent on surface chemistry and topography. We found out earlier that osteoblasts on sharp-edged micro-topographies revealed an impaired cell phenotype and function and the cells attempted to phagocytize these spiky elevations in vitro. Therefore, micro-structured implants used in dental surgery should avoid any spiky topography on their surface. The sandblasted, acid-etched, and heat-treated yttria-stabilized zirconia (cer.face®14) surface was characterized by scanning electron microscopy and energy dispersive X-ray. In vitro studies with human MG-63 osteoblasts focused on cell attachment and intracellular stress level. The cer.face 14 surface featured a landscape with nano-micro hills that was most sinusoidal-shaped. The mildly curved profile proved to be a suitable material for cell anchorage. MG-63 cells on cer.face 14 showed a very low reactive oxygen species (ROS) generation similar to that on the extracellular matrix protein collagen I (Col). Intracellular adenosine triphosphate (ATP) levels were comparable to Col. Ceramic cer.face 14, with its sinusoidal-shaped surface structure, facilitates cell anchorage and prevents cell stress.


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
W. Blake Martin ◽  
Renaud Sicard ◽  
Shabnam M. Namin ◽  
Timothy Ganey

Debridement of the bone surface during a surgical fusion procedure initiates an injury response promoting a healing cascade of molecular mediators released over time. Autologous grafts offer natural scaffolding to fill the bone void and to provide local bone cells. Commercial bone grafting products such as allografts, synthetic bone mineral products, etc., are used to supplement or to replace autologous grafts by supporting osteoinductivity, osteoconductivity, and osteogenesis at the surgical site. To assure osteogenic potential, preservation of allogeneic cells with cryoprotectants has been developed to allow for long-term storage and thus delivery of viable bone cells to the surgical site. Dimethyl sulfoxide (DMSO) is an intracellular cryoprotectant commonly used because it provides good viability of the cells post-thaw. However, there is known cytotoxicity reported for DMSO when cells are stored above cryogenic temperatures. For most cellular bone graft products, the cryoprotectant is incorporated with the cells into the other mineralized bone and demineralized bone components. During thawing, the DMSO may not be sufficiently removed from allograft products compared to its use in a cell suspension where removal by washing and centrifugation is available. Therefore, both the allogeneic cell types in the bone grafting product and the local cell types at the bone grafting site could be affected as cytotoxicity varies by cell type and by DMSO content according to reported studies. Overcoming cytotoxicity may be an additional challenge in the formation of bone at a wound or surgical site. Other extracellular cryoprotectants have been explored as alternatives to DMSO which preserve without entering the cell membrane, thereby providing good cellular viability post-thaw and might abrogate the cytotoxicity concerns.


Author(s):  
Shivaji Kashte ◽  
Gajanan Arbade ◽  
R.K. Sharma ◽  
Sachin Kadam

In the bone tissue engineering composite scaffolds with osteogenic potential are emerging as the new tool. Here, we investigated the graphene (GP), graphene oxide (GO) andCissusquadrangularis(CQ) callus extract for their spontaneous osteoinductive potential. Electrospun poly ε-caprolactone (PCL) sheets were painted with varying combination GP, GO and CQ solutions as ink. The prepared PCL-GO, PCL-GO-CQ, PCL-GP and PCL-GP-CQ scaffolds were characterized for their physical, mechanical and biological properties. Addition of GO, GP, GO-CQ and GP-CQ to PCL enhanced roughness, wettability, Yield strength and tensile strength, biocompatibility .significantly. Presence of GO and CQ in PCL-GO-CQ scaffolds, while GP and CQ in PCL-GP-CQ scaffolds showed synergistic effect on the biocompatibility, Cell attachment,cell proliferation of human umbilical Wharton’s jelly derived mesenchymal stem cells (hUCMSCs) and their differentiation into osteoblasts by 21stday in culture without osteogenic differentiation media or any growth factors. Same is confirmed by the Alizarin red S staining and Von kossa staining. The combination of PCL-GO-CQ scaffold prepared by novel paint method was found to be the most potential in bone tissue engineering.


2020 ◽  
Vol 846 ◽  
pp. 23-28
Author(s):  
Bambang Suharno ◽  
Nabila Ramadhanti ◽  
Nadya Aryani ◽  
Ahmad Zakiyuddin ◽  
Sugeng Supriadi

Ti-6Al-4V as an implant material has bio-inert properties, so it does not support any tissues or bone cells reaction. This study aims to increase the tendency of osteoblast's cell attachment to the surface of implant Ti-6Al-4V by fabricating nanotube structure on the surface by anodization. This study also conducted to study the effect of elements from titanium alloys and organic electrolytes on the mechanism of formation of nanotube structures. The anodization method was chosen because it was easy to do, effective, and inexpensive. The samples were prepared by ground and polished, then washed by ultrasonic. Anodization used organic electrolytes in the form of a mixture of ethylene glycol, 0.5 M NH4F, and 4 w.t% deionized water. The study of the effect of voltage and duration time was carried out to understand the mechanism of nanotube formation, through morphological observation on the surface and cross-section area of nanotubes using SEM and characterization of elements using EDS, diameter, and length of highly ordered nanotubes was observed. The results of the characterization showed that the tube diameter is adjusted by the voltage, while duration time influence the tube length, with a linear relationship, so the widest diameter achieved at 40V 5h, but the longest tube achieved at 30 V 5h. Whereas for 5h duration, the upper part of the tube collapsed and disintegrated. The fluoride ions incorporated at the tube surfaces formed fluoride-titanium oxide cubic agglomerates, and the whole nanotube surface was oxide.


2012 ◽  
Vol 717-720 ◽  
pp. 889-892 ◽  
Author(s):  
Hamidreza Zamani ◽  
Seung Wan Lee ◽  
Amir Avishai ◽  
Christian A. Zorman ◽  
R. Mohan Sankaran ◽  
...  

We report on experimental explorations of using focused ion beam (FIB) nanomachining of different types of silicon carbide (SiC) thin membranes, for making robust, high-quality stencil masks for new emerging options of nanoscale patterning. Using thin films and membranes in polycrystalline SiC (poly-SiC), 3C-SiC, and amorphous SiC (a-SiC) with thicknesses in the range of t~250nm−1.6μm, we have prototyped a series of stencil masks, with nanoscale features routinely down to ~100nm.


Sign in / Sign up

Export Citation Format

Share Document