WorldWideScience

Sample records for bioactive ceramic-based materials

  1. Emerging Ceramic-based Materials for Dentistry

    OpenAIRE

    Denry, I.; Kelly, J. R.

    2014-01-01

    Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appr...

  2. Emerging Ceramic-based Materials for Dentistry

    Science.gov (United States)

    Denry, I.; Kelly, J.R.

    2014-01-01

    Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appropriate, the authors have added their opinions and guidance. PMID:25274751

  3. Applied bioactive polymeric materials

    CERN Document Server

    Carraher, Charles; Foster, Van

    1988-01-01

    The biological and biomedical applications of polymeric materials have increased greatly in the past few years. This book will detail some, but not all, of these recent developments. There would not be enough space in this book to cover, even lightly, all of the major advances that have occurred. Some earlier books and summaries are available by two of this book's Editors (Gebelein & Carraher) and these should be consul ted for additional information. The books are: "Bioactive Polymeric Systems" (Plenum, 1985); "Polymeric Materials In Medication" (Plenum, 1985); "Biological Acti vi ties of Polymers" (American Chemical Society, 1982). Of these three, "Bioacti ve Polymeric Systems" should be the most useful to a person who is new to this field because it only contains review articles written at an introductory level. The present book primarily consists of recent research results and applications, with only a few review or summary articles. Bioactive polymeric materials have existed from the creation of life...

  4. Tough hybrid ceramic-based material with high strength

    International Nuclear Information System (INIS)

    This study describes a tough and strong hybrid ceramic material consisting of platelet-like zirconium compounds and metal. A mixture of boron carbide and excess zirconium powder was heated to 1900 °C using a liquid-phase reaction sintering technique to produce a platelet-like ZrB2-based hybrid ceramic bonded by a thin zirconium layer. The platelet-like ZrB2 grains were randomly present in the as-sintered hybrid ceramic. Relative to non-hybrid ceramics, the fracture toughness and flexural strength of the hybrid ceramic increased by approximately 2-fold.

  5. Thermoluminescence dating (TL-Dating): an absolute method for archeological dating of ceramic base materials

    International Nuclear Information System (INIS)

    Thermoluminescence dating is one of the known techniques that have been established in many laboratories across the regions. This technique is capable to date the archeological ceramic base materials and provides an absolute measurement with an accuracy of 5%. The study involves the dating of ceramic clay from historical site at Sungai Mas, Kuala Muda, Kedah. Pieces of broken poetry of archeological sample excavated by the Museum Department and Antiquity (JM4) have been dated using the TLD techniques at MINT laboratory. A TLD dosemeter of LiF chips is used for the background and sample dose measurement. The preparation of sample and the calibration techniques for the estimation of palaedose or dose presented in the sample since distant past is established. Results indicate that the samples are in the era of civilization from 200BP to 1600BP. Error factors associated in the measurement procedures are also discussed

  6. Thermoluminescence dating (TL-dating): measurement and accuracy factors in archaeological dating of ceramic base materials

    International Nuclear Information System (INIS)

    Thermoluminescence dating is one of the known techniques that have been established in many laboratories across the region. This technique is capable of dating the archaeological ceramic base materials and provide an absolute measurement with an accuracy of ±15%. The study involves the dating of pottery from a historical site at Sungai Mas, Mukim Kota, Daerah Kuala Muda, Kedah. Pieces of broken pottery of archaeological sample excavated by the Museum Department and Antiquity (JMA) have been dated using the thermoluminescence detector (TLD) techniques at MINT laboratory. A TLD dosemeter of LiF chips is used for the measurement of background and sample dose measurement. The preparation of sample and the calibration techniques for the estimation of palaedose or dose presented in the sample since distant past is established. Results indicate that the samples are in the era of civilization from 200 BP to 1600 BP. Error factors associated in the measurement procedures were identified and discussed. (Author)

  7. Bioactive glasses materials, properties and applications

    CERN Document Server

    Ylänen, Heimo

    2011-01-01

    Due to their biocompatibility and bioactivity, bioactive glasses are used as highly effective implant materials throughout the human body to replace or repair damaged tissue. As a result, they have been in continuous use since shortly after their invention in the late 1960s and are the subject of extensive research worldwide.Bioactive glasses provides readers with a detailed review of the current status of this unique material, its properties, technologies and applications. Chapters in part one deal with the materials and mechanical properties of bioactive glass, examining topics such

  8. Sintered gahnite–cordierite glass-ceramic based on raw materials with different fluorine sources

    Indian Academy of Sciences (India)

    Esmat M A Hamzawy; Mohammed A Bin Hussain

    2015-12-01

    Glass-ceramic based on Zn-containing cordierite was prepared from kaolin, silica'sand and commercial ZnO. The addition of AlF3, MgF2 and CaF2 was performed as nucleation catalysts. Dark brown glasses were obtained from the glass batches. The transformation and crystallization temperatures were in the range of 739–773 and 972–1007°C, respectively. Gahnite, cordierite and very little enstatite were the development crystalline phases through the heating and sintering process between 1000 and 1340°C. The microstructure of crystallized samples at 1340°C showed the appearance of dominant euhedral octahedral crystals of gahnite and hexagonal cordierite, in the low micro-scale, disseminated in the glassy matrix. The microanalysis of the crystallized samples indicated that Zn and Mg may replace each other in gahnite and cordierite structure. Densities of the crystallized samples were between 2.2517 and 2.5278 g cm−3. The thermal expansion of the crystallized samples was ranging from 19.22 to 59.30 × 10−7°C−1. However, the higher crystallization of both cordierite and gahnite accompany with the higher values of densities and the lower values of coefficient of thermal expansion.

  9. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    Science.gov (United States)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2016-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  10. Novel Processing of Unique Ceramic-Based Nuclear Materials and Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Hui Zhang; Raman P. Singh

    2008-11-30

    Advances in nuclear reactor technology and the use of gas-cooled fast reactors require the development of new materials that can operate at the higher temperatures expected in these systems. These include refractory alloys base on Nb, Zr, Ta, Mo, W, and Re; ceramics and composites such as those based on silicon carbide (SiCf-SiC); carbon-carbon composites; and advanced coatings. Besides the ability to handle higher expected temperatures, effective heat transfer between reactor componets is necessary for improved efficiency. Improving thermal conductivity of the materials used in nuclear fuels and other temperature critical components can lower the center-line fuel temperature and thereby enhance durability and reduce the risk of premature failure.

  11. Novel Processing of Unique Ceramic-Based Nuclear Materials and Fuels

    International Nuclear Information System (INIS)

    Advances in nuclear reactor technology and the use of gas-cooled fast reactors require the development of new materials that can operate at the higher temperatures expected in these systems. These include refractory alloys base on Nb, Zr, Ta, Mo, W, and Re; ceramics and composites such as those based on silicon carbide (SiCf-SiC); carbon-carbon composites; and advanced coatings. Besides the ability to handle higher expected temperatures, effective heat transfer between reactor components is necessary for improved efficiency. Improving thermal conductivity of the materials used in nuclear fuels and other temperature critical components can lower the center-line fuel temperature and thereby enhance durability and reduce the risk of premature failure.

  12. Radiation technology for immobilization of bioactive materials

    International Nuclear Information System (INIS)

    Within the framework of the Agency's coordinated research programme on ''Application of Radiation Technology in Immobilization of Bioactive Materials'', the third and final research coordination meeting was held at Beijing University, Beijing, People's Republic of China, 15-18 June 1987. The present publication compiles all presentations made at the meeting. Fundamental processes for the immobilization of enzymes, antibodies, cells and drugs were developed and established using gamma radiation, electron beams and plasma discharge. Applications of various biofunctional components, immobilized by radiation techniques in different processes, were studied. A range of backbone polymers has been examined together with various monomers. Coupling procedures have been developed which are relevant to our particular requirements. Enzymes of various types and characteristics have been immobilized with considerable efficiency. The immobilized biocatalysts have been shown to possess significant activity and retention of activity on storage. There appears to be a high degree of specificity associated with the properties of the immobilised biocatalysts, their activity and the ease of their preparation. Novel additives which lower the total radiation dose in grafting have been discovered and their value in immobilization processes assessed. Potential applications include: medical (diagnostic, therapeutic), and industrial processes (fermentation, bioseparation, etc.). Refs, figs and tabs

  13. Interactions of bioactive glass materials in the oral environment

    Science.gov (United States)

    Efflandt, Sarah Elizabeth

    The aim of this research was to investigate bioactive glass materials for their use in dental restorations. Mechanical properties such as strength, toughness and wear resistance were considered initially, but the focus of this thesis was the biological properties such as reactions with saliva and interactions with natural dental tissues. Bioactive composite materials were created by incorporating bioactive glass and alumina powders into an aqueous suspension, slip casting, and infiltrating with resin. Microstructure, mechanical properties and wear resistance were evaluated. Mechanically, the composites are comparable to natural dental tissues and current dental materials with a strength of 206 +/- 18.7 MPa and a toughness of 1.74 +/- 0.08 MPa(m)1/2. Interfacial reactions were examined using bulk bioactive glasses. Disks were prepared from a melt, placed in saliva and incubated at 37°C. Surfaces were analyzed at 2, 5, 10, 21, and 42 days using scanning electron microscopy (SEM) and microdiffraction. Results showed changes at 2 days with apatite crystallization by 10 days. These glass disks were then secured against extracted human dentin and incubated in saliva for 21 or 42 days. Results from SEM, electron microprobe analysis (EMPA) and microdiffraction showed that dentin and bioactive glasses adhered in this in vitro environment due to attraction of collagen to bioactive glasses and growth of an interfacial apatite. After investigating these bulk glass responses, particulate bioactive glasses were placed in in vitro and in vivo set-ups for evaluation. Particles immersed in biologically buffered saliva showed crystallization of apatite at 3 days. These bioactive glass particles were placed in the molars of mini-pigs and left in vivo. After 30 days the bioactive paste was evaluated using SEM, EMPA and microdiffraction analyses. Results showed that the paste gained structural integrity and had chemical changes in vivo. These sets of experiments show that bioactive

  14. Development of bioactive microspheres for the functionalization of textile materials

    OpenAIRE

    Faustino, Graça Maria Alves

    2010-01-01

    The development of functional medical textiles, including cosmetics, will have a positive impact on quality of life as textiles, when in direct contact and non-obstructive to the surface of the human body, can act as backers of therapeutic agents. Have adequate protection against infection by taking preventive action combined with the comfort features. Thus, the functionalization of textile materials with bioactive microspheres will produce products previously unthinkable as ag...

  15. Joining of SiC ceramic-based materials with ternary carbide Ti3SiC2

    International Nuclear Information System (INIS)

    The joining of two pieces of SiC-based ceramic materials (SiC or Cf/SiC composite) was conducted using Ti3SiC2 as filler in vacuum in the joining temperatures range from 1200 deg. C to 1600 deg. C. The similar chemical reactions took place at the interface between Ti3SiC2 and SiC or Cf/SiC, and became more complete with joining temperature increases, and with the consequent increased joining strengths of the SiC and Cf/SiC joints. Based on the XRD and SEM analyses, it turns out that two reasons are most important for the high joining strengths of the SiC and Cf/SiC joints. One is the development of layered Ti3SiC2 ceramic, which has plasticity in nature and can contribute to thermal stress relaxation of the joints; the other is the chemical reactions between Ti3SiC2 and the base materials which result in good interface bonding.

  16. Histological evaluation of bone response to bioactive ceramics as graft material in rats

    Directory of Open Access Journals (Sweden)

    Kršljak Elena

    2005-01-01

    Full Text Available This experimental study was carried out on 35 Albino Wister rats Artificially created bone defects were grafted with bioactive ceramic materials or control material. Histological analysis was preformed 8 weeks and 6 months after the implantation. The results revealed that bone regeneration occurred in defects treated with bioactive ceramic materials while in the defects treated with the control material signs of tissue rejection were present. As stated before, it could be concluded that bioactive ceramics can be recommended as bone substitutes in orthopedic surgery and dentistry.

  17. Quantitative assessment of the interfacial roughness in multi-layered materials using image analysis: Application to oxidation in ceramic-based materials

    OpenAIRE

    Le Roux, Sabine; Deschaux-Beaume, Frédéric; Cutard, Thierry; Lours, Philippe

    2015-01-01

    A method is developed to characterize interfacial roughness of layered materials. A series of contiguous images is acquired with a Scanning Electron Microscope on polished cross-sections. Using image analysis algorithms based on mathematical morphology operations, interface profiles are extracted and mathematically processed to calculate standard surface roughness parameters. In addition, morphological criteria describing the interface tortuosity are determined, such as the " normalized rumpl...

  18. Preparation and application of highly porous aerogel-based bioactive materials in dentistry

    Science.gov (United States)

    Kuttor, Andrea; Szalóki, Melinda; Rente, Tünde; Kerényi, Farkas; Bakó, József; Fábián, István; Lázár, István; Jenei, Attila; Hegedüs, Csaba

    2014-03-01

    In this study, the possibility of preparation and application of highly porous silica aerogel-based bioactive materials are presented. The aerogel was combined with hydroxyapatite and β-tricalcium phosphate as bioactive and osteoinductive agents. The porosity of aerogels was in the mesoporous region with a maximum pore diameter of 7.4 and 12.7 nm for the composite materials. The newly developed bioactive materials were characterized by scanning electron microscopy. The in vitro biological effect of these modified surfaces was also tested on SAOS-2 osteogenic sarcoma cells by confocal laser scanning microscopy.

  19. Silica-Gelatin Composite Materials for Prolonged Desorption of Bioactive Compounds

    OpenAIRE

    Oksana STAVINSKAYA; Iryna LAGUTA; Inna OREL

    2014-01-01

    The set of gelatin and silica-gelatin films with incorporated bioactive compounds of different chemical nature was prepared. The swelling behavior of the films and desorption of active ingredients into aqueous media were studied. For all the silica-gelatin films we observed considerable improvement of the materials water stability and retardation of the release of bioactive compounds as compared to gelatin samples. The results obtained make it possible to consider silica-gelatin composite mat...

  20. Bioactivity and degradability of hybrids nano-composites materials with great application as bone tissue substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Téllez, D.A.; Téllez-Jurado, L.; Chávez-Alcalá, J.F., E-mail: fchaveza@hotmail.com

    2014-12-05

    Highlights: • pH has an effect on the degradation process of the hybrid materials. • Weight loss depends on the change of pH during the degradation process. • Bioactivity in the materials is strongly related to calcium and pH. - Abstract: In this work, hybrids with great application as bioactive materials having different compositions based on siloxane network were prepared. In vitro bioactivity and in vitro degradability tests were carried out in the materials by soaking them into simulated body fluid (SBF) and into phosphate buffer solution (PBS) to prove their apatite-forming ability and to show their degradation process, respectively. In both in vitro tests, measurements of pH and loss weight were made to observe bioactivity and degradation processes. To prove growth of HA, the materials were characterized through X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The results showed that some samples have better bioactivity than others. It was found that the incorporation of CaO component into the network of the materials results in an increase of the apatite-forming ability in SBF. Moreover, during the degradation tests, all the samples presented weight loss, especially the ones that contain CaO.

  1. Influence of thermal treatment on the "in vitro" bioactivity of wollastonite materials.

    Science.gov (United States)

    de la Casa-Lillo, Miguel A; Velásquez, Pablo; De Aza, Piedad N

    2011-04-01

    The aim of this work was to study the influence of the composition and thermal treatment of the in vitro bioactivity of wollastonite materials obtained by sol-gel method. For this purpose, gels in the system SiO(2)-CaO were obtained applying calcium nitrate and tetraethoxysilicate as precursors. The gels were heated to 700 °C and then sintered up to 1400 °C. The bioactivity of the gel-derived materials in simulated body fluid (SBF) was investigated and characterized. Additional changes in ionic concentration, using inductively couple plasma atomic emission spectroscopy (ICP-AES), were determined. The results showed that all materials obtained were bioactive and indicate that the absence of phosphorous in the material composition is not an essential requirement for the development of a Hydroxyapatite layer. The bioactivity was influenced by the thermal treatment, the different phases (glass-phase, wollastonite and pseudowollastonite) as well as the porous size. On the gel-derived materials the bioactivity decreased with the sintering temperature. PMID:21336850

  2. Preparation and in vitro bioactivity of hydroxyapatite/solgel glass biphasic material.

    Science.gov (United States)

    Ragel, C V; Vallet-Regí, M; Rodríguez-Lorenzo, L M

    2002-04-01

    Hydroxyapatite/solgel glass biphasic material has been obtained in order to improve the bioactivity of the hydroxyapatite (OHAp). A mixture of stoichiometric OHAp and the precursor gel of a solgel glass, with nominal composition in mol% CaO-26, SiO2-70, P205-4, has been prepared. The amounts of components used have been selected to obtain a final relationship for OHAp/solgel glass of 60/40 on heating. Two different thermal treatments have been used: (i) 700 degrees C, temperature of solgel glass stabilisation and (ii) 1000 degrees C, lower temperature of hydroxyapatite sintering. The bioactivity of the resulting materials has been examined in vitro by immersion in simulated body fluid at 37 degrees C. The results obtained show that both materials are bioactive. The apatite-like layer grown is greater for the new materials than for the OHAp and the solgel glass themselves. PMID:11950057

  3. Designing antimicrobial bioactive glass materials with embedded metal ions synthesized by the sol–gel method

    International Nuclear Information System (INIS)

    Bioactive glasses (SiO2–P2O5–CaO) having tailored concentrations of different biocide metal ions (copper or silver) were produced by the sol–gel method. All the particles release phosphorous ions when immersed in water and simulated body fluid (SBF). Moreover, a surface layer of polycrystalline hydroxy-carbonate apatite was formed on the particle surfaces after 10 day immersion in SBF as confirmed by X-ray diffraction and scanning electron microscopy (SEM) showing the bioactive materials. Samples with embedded either copper or silver ions were able to further release the biocide ions with a release rate that depends on the metal embedded and the dissolution medium: water or SBF. This biocide ion release from the samples explains the antimicrobial effect of our active particles against Escherichia coli DH5α ampicillin-resistant (Gram-negative) and Streptococcus mutans (Gram-positive) as determined by the Minimum Bactericidal Concentration (MBC) method. The antimicrobial behavior of the particles depends on the bacteria and the biocide ion used. Noteworthy, although samples with copper are able to release more metal ion than samples with silver, they present higher MBC showing the high effect of silver against these bacteria. - Highlights: • Copper and silver act as antimicrobial additives in bioactive glass materials. • Silver is more toxic than copper ions in these bioactive materials. • Sol–gel method allows the synthesis of antimicrobial bioactive materials

  4. Designing antimicrobial bioactive glass materials with embedded metal ions synthesized by the sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Palza, Humberto, E-mail: hpalza@ing.uchile.cl [Departamento de Ingeniería Química y Biotecnología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago (Chile); Escobar, Blanca; Bejarano, Julian [Departamento de Ingeniería Química y Biotecnología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago (Chile); Bravo, Denisse [Departamento de Patología, Facultad de Odontología, Universidad de Chile, Santiago (Chile); Diaz-Dosque, Mario [Departamento de Ciencias Básicas y Comunitarias, Facultad de Odontología, Universidad de Chile, Santiago (Chile); Perez, Javier [Departamento de Ingeniería Química y Biotecnología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago (Chile)

    2013-10-15

    Bioactive glasses (SiO{sub 2}–P{sub 2}O{sub 5}–CaO) having tailored concentrations of different biocide metal ions (copper or silver) were produced by the sol–gel method. All the particles release phosphorous ions when immersed in water and simulated body fluid (SBF). Moreover, a surface layer of polycrystalline hydroxy-carbonate apatite was formed on the particle surfaces after 10 day immersion in SBF as confirmed by X-ray diffraction and scanning electron microscopy (SEM) showing the bioactive materials. Samples with embedded either copper or silver ions were able to further release the biocide ions with a release rate that depends on the metal embedded and the dissolution medium: water or SBF. This biocide ion release from the samples explains the antimicrobial effect of our active particles against Escherichia coli DH5α ampicillin-resistant (Gram-negative) and Streptococcus mutans (Gram-positive) as determined by the Minimum Bactericidal Concentration (MBC) method. The antimicrobial behavior of the particles depends on the bacteria and the biocide ion used. Noteworthy, although samples with copper are able to release more metal ion than samples with silver, they present higher MBC showing the high effect of silver against these bacteria. - Highlights: • Copper and silver act as antimicrobial additives in bioactive glass materials. • Silver is more toxic than copper ions in these bioactive materials. • Sol–gel method allows the synthesis of antimicrobial bioactive materials.

  5. The Use of Nanoscaled Fibers or Tubes to Improve Biocompatibility and Bioactivity of Biomedical Materials

    Directory of Open Access Journals (Sweden)

    Xiaoming Li

    2013-01-01

    Full Text Available Nanofibers and nanotubes have recently gained substantial interest for potential applications in tissue engineering due to their large ratio of surface area to volume and unique microstructure. It has been well proved that the mechanical property of matrix could be largely enhanced by the addition of nanoscaled fibers or tubes. At present, more and more researches have shown that the biocompatibility and bioactivity of biomedical materials could be improved by the addition of nanofibers or nanotubes. In this review, the efforts using nanofibers and nanotubes to improve biocompatibility and bioactivity of biomedical materials, including polymeric nanofibers/nanotubes, metallic nanofibers/nanotubes, and inorganic nanofibers/nanotubes, as well as their researches related, are demonstrated in sequence. Furthermore, the possible mechanism of improving biocompatibility and bioactivity of biomedical materials by nanofibers or nanotubes has been speculated to be that the specific protein absorption on the nanoscaled fibers or tubes plays important roles.

  6. Bioactive hydrogel-nanosilica hybrid materials: a potential injectable scaffold for bone tissue engineering

    International Nuclear Information System (INIS)

    Novel bioactive organic–inorganic hybrid materials that can serve as injectable hydrogel systems for bone tissue regeneration were obtained. The silica nanoparticles (SiNP) prepared in situ by the Stöber method were dispersed in collagen, collagen-chitosan or chitosan sols, which were then subsequently crosslinked. Laser scanning confocal microscopy studies, in which fluorescent SiNP were applied, and SEM images indicated that the nanosilica particles were distributed in the whole volume of the hydrogel matrix. In vitro studies on fibroblast cell viability indicated that the hybrid materials are biocompatible. The silica nanoparticles dispersed in the biopolymer matrix had a positive effect on cell viability. Studies on the mineralization process under simulated body fluid (SBF) conditions confirmed the bioactivity of prepared materials. SEM images revealed mineral phase formation in the majority of the hybrid materials developed. EDS analysis indicated that these mineral phases are mainly composed of calcium and phosphorus. The XRD studies confirmed that mineral phases formed during SBF incubation of hybrid materials based on collagen are bone-like apatite minerals. The silica nanoparticles added to the hydrogel at the stage of synthesis induced the occurrence of mineralization. This process occurs not only at the surface of the material but in its entire volume, which is important for the preparation of scaffolds for bone tissue engineering. The ability of these materials to undergo in situ gelation under physiological temperature and their bioactivity as well as biocompatibility make them interesting candidates for bioactive injectable systems. (paper)

  7. Novel bioactive materials: silica aerogel and hybrid silica aerogel/pseudo wollastonite

    Energy Technology Data Exchange (ETDEWEB)

    Resendiz-Hernandez, P. J.; Cortes-Hernandez, D. a.; Saldivar-Ramirez, M. M. G.; Acuna-gutierrez, I. O.; Flores-Valdes, A.; Torres-rincon, S.; Mendez-Nonell, J.

    2014-07-01

    Silica aerogel and hybrid silica aerogel/pseudo wollastonite materials were synthesized by controlled hydrolysis of tetraethoxysilane (TEOS) using also methanol (MeOH) and pseudo wollastonite particles. The gels obtained were dried using a novel process based on an ambient pressure drying. Hexane and hexamethyl-disilazane (HMDZ) were the solvents used to chemically modify the surface. In order to assess bioactivity, aerogels, without and with pseudowollastonite particles, were immersed in simulated body fluid (SBF) for 7 and 14 days. The hybrid silica aerogel/pseudo wollastonite showed a higher bioactivity than that observed for the single silica aerogel. However, as in both cases a lower bioactivity was observed, a biomimetic method was also used to improve it. In this particular method, samples of both materials were immersed in SBF for 7 days followed by their immersion in a more concentrated solution (1.5 SBF) for 14 days. A thick and homogeneous bonelike apatite layer was formed on the biomimetically treated materials. Thus, bioactivity was successfully improved even on the aerogel with no pseudowollastonite particles. As expected, the hybrid silica aerogel/pseudowollastonite particles showed a higher bioactivity. (Author)

  8. Novel bioactive materials: silica aerogel and hybrid silica aerogel/pseudo wollastonite

    International Nuclear Information System (INIS)

    Silica aerogel and hybrid silica aerogel/pseudo wollastonite materials were synthesized by controlled hydrolysis of tetraethoxysilane (TEOS) using also methanol (MeOH) and pseudo wollastonite particles. The gels obtained were dried using a novel process based on an ambient pressure drying. Hexane and hexamethyl-disilazane (HMDZ) were the solvents used to chemically modify the surface. In order to assess bioactivity, aerogels, without and with pseudowollastonite particles, were immersed in simulated body fluid (SBF) for 7 and 14 days. The hybrid silica aerogel/pseudo wollastonite showed a higher bioactivity than that observed for the single silica aerogel. However, as in both cases a lower bioactivity was observed, a biomimetic method was also used to improve it. In this particular method, samples of both materials were immersed in SBF for 7 days followed by their immersion in a more concentrated solution (1.5 SBF) for 14 days. A thick and homogeneous bonelike apatite layer was formed on the biomimetically treated materials. Thus, bioactivity was successfully improved even on the aerogel with no pseudowollastonite particles. As expected, the hybrid silica aerogel/pseudowollastonite particles showed a higher bioactivity. (Author)

  9. Bioactive treatment promotes osteoblast differentiation on titanium materials fabricated by selective laser melting technology.

    Science.gov (United States)

    Tsukanaka, Masako; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Matsushita, Tomiharu; Kokubo, Tadashi; Nakamura, Takashi; Sasaki, Kiyoyuki; Matsuda, Shuichi

    2016-01-01

    Selective laser melting (SLM) technology is useful for the fabrication of porous titanium implants with complex shapes and structures. The materials fabricated by SLM characteristically have a very rough surface (average surface roughness, Ra=24.58 µm). In this study, we evaluated morphologically and biochemically the specific effects of this very rough surface and the additional effects of a bioactive treatment on osteoblast proliferation and differentiation. Flat-rolled titanium materials (Ra=1.02 µm) were used as the controls. On the treated materials fabricated by SLM, we observed enhanced osteoblast differentiation compared with the flat-rolled materials and the untreated materials fabricated by SLM. No significant differences were observed between the flat-rolled materials and the untreated materials fabricated by SLM in their effects on osteoblast differentiation. We concluded that the very rough surface fabricated by SLM had to undergo a bioactive treatment to obtain a positive effect on osteoblast differentiation. PMID:26830832

  10. Research on the preparation, biocompatibility and bioactivity of magnesium matrix hydroxyapatite composite material.

    Science.gov (United States)

    Linsheng, Li; Guoxiang, Lin; Lihui, Li

    2016-08-12

    In this paper, magnesium matrix hydroxyapatite composite material was prepared by electrophoretic deposition method. The optimal process parameters of electrophoretic deposition were HA suspension concentration of 0.02 kg/L, aging time of 10 days and voltage of 60 V. Animal experiment and SBF immersion experiment were used to test the biocompatibility and bioactivity of this material respectively. The SD rats were divided into control group and implant group. The implant surrounding tissue was taken to do tissue biopsy, HE dyed and organizational analysis after a certain amount of time in the SD rat body. The biological composite material was soaked in SBF solution under homeothermic condition. After 40 days, the bioactivity of the biological composite material was evaluated by testing the growth ability of apatite on composite material. The experiment results showed that magnesium matrix hydroxyapatite biological composite material was successfully prepared by electrophoretic deposition method. Tissue hyperplasia, connective tissue and new blood vessels appeared in the implant surrounding soft tissue. No infiltration of inflammatory cells of lymphocytes and megakaryocytes around the implant was found. After soaked in SBF solution, a layer bone-like apatite was found on the surface of magnesium matrix hydroxyapatite biological composite material. The magnesium matrix hydroxyapatite biological composite material could promot calcium deposition and induce bone-like apatite formation with no cytotoxicity and good biocompatibility and bioactivity. PMID:27567779

  11. Direct pulp capping in an immature incisor using a new bioactive material

    Directory of Open Access Journals (Sweden)

    Sham S Bhat

    2014-01-01

    Full Text Available Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future.

  12. Building ceramic based on sludge

    Science.gov (United States)

    Szöke, A.-M.; Muntean, M.; Dumitrescu, O.; Bartalis, I.

    2013-12-01

    Because of the rapid evolution in the last decade of science and engineering materials, development of new advanced materials, particularly in construction, we must find solutions, namely, new performed materials, with functional and aesthetic qualities. In recent years, there have been made alternative attempts to reuse various types of wastes, including the incorporation of products in ceramic clay. This theme concerning the achievement of some durable, economic and ecological materials represents a high-level preoccupation in this domain, the problems related to the ecosystem being permanent issues of the century.

  13. Building ceramic based on sludge

    International Nuclear Information System (INIS)

    Because of the rapid evolution in the last decade of science and engineering materials, development of new advanced materials, particularly in construction, we must find solutions, namely, new performed materials, with functional and aesthetic qualities. In recent years, there have been made alternative attempts to reuse various types of wastes, including the incorporation of products in ceramic clay. This theme concerning the achievement of some durable, economic and ecological materials represents a high-level preoccupation in this domain, the problems related to the ecosystem being permanent issues of the century

  14. Current Progress in Bioactive Ceramic Scaffolds for Bone Repair and Regeneration

    Directory of Open Access Journals (Sweden)

    Chengde Gao

    2014-03-01

    Full Text Available Bioactive ceramics have received great attention in the past decades owing to their success in stimulating cell proliferation, differentiation and bone tissue regeneration. They can react and form chemical bonds with cells and tissues in human body. This paper provides a comprehensive review of the application of bioactive ceramics for bone repair and regeneration. The review systematically summarizes the types and characters of bioactive ceramics, the fabrication methods for nanostructure and hierarchically porous structure, typical toughness methods for ceramic scaffold and corresponding mechanisms such as fiber toughness, whisker toughness and particle toughness. Moreover, greater insights into the mechanisms of interaction between ceramics and cells are provided, as well as the development of ceramic-based composite materials. The development and challenges of bioactive ceramics are also discussed from the perspective of bone repair and regeneration.

  15. Fermentation of Plant Material - Effect on Sugar Content and Stability of Bioactive Compounds

    OpenAIRE

    Reis Bruno A. dos; Kosińska-Cagnazzo Agnieszka; Schmitt Rudolf; Andlauer Wilfried

    2014-01-01

    Extraction is a method often used to obtain products rich in bioactive compounds from plant material. Most of the solvents used for the poly-phenols extraction simultaneously extract also sugars, undesirable as a component of health-promoting food. Fermentation might be a simple, cheap and efficient way of sugar elimination. In our study, black tea and goji berries, both known for their health benefits, were used and alcoholic fermentation by Saccharomyces cerevisiae was carried out to elimin...

  16. The Use of Nanoscaled Fibers or Tubes to Improve Biocompatibility and Bioactivity of Biomedical Materials

    OpenAIRE

    Fuzhai Cui; Qingling Feng; Yubo Fan; Bo Yu(Brookhaven National Lab); Lianwen Sun; Wei Liu; Rongrong Cui; Xiaoming Li; Fumio Watari

    2013-01-01

    Nanofibers and nanotubes have recently gained substantial interest for potential applications in tissue engineering due to their large ratio of surface area to volume and unique microstructure. It has been well proved that the mechanical property of matrix could be largely enhanced by the addition of nanoscaled fibers or tubes. At present, more and more researches have shown that the biocompatibility and bioactivity of biomedical materials could be improved by the addition of nanofibers or na...

  17. Structure and bioactivity studies of new polysiloxane-derived materials for orthopedic applications

    Science.gov (United States)

    Paluszkiewicz, Czesława; Gumuła, Teresa; Podporska, Joanna; Błażewicz, Marta

    2006-07-01

    The aim of this work was to examine the structure of new calcium silicate bioactive ceramic implant material for bone surgery applications. The bioceramic material was obtained by thermal treatment of active fillers-containing organosilicon polymer precursor. Different ceramic active fillers, namely Ca(OH) 2, CaCO 3, Na 2HPO 4 and SiO 2 powders were used. The phase composition of ceramic samples obtained by thermal transformation of active fillers containing polysiloxane was investigated. Morphology and structure of ceramic phases were characterized by means of scanning electron microscopy (SEM) with EDS point analysis, FTIR spectroscopy and XRD analysis. It was found that thermal treatment of active fillers-containing organosilicon precursor lead to the formation of wollastonite-containing ceramic material. This ceramic material showed bioactivity in 'in vitro' conditions studied by immersing the samples in simulated body fluid (SBF). The surface of wollastonite-containing ceramic before and after immersion in SBF was analysed. It can be concluded that this kind of ceramic material may be useful as bone substitute. FTIR spectroscopy is an adequate device for the determination of such derived materials structure.

  18. Fermentation of Plant Material - Effect on Sugar Content and Stability of Bioactive Compounds

    Directory of Open Access Journals (Sweden)

    Reis Bruno A. dos

    2014-12-01

    Full Text Available Extraction is a method often used to obtain products rich in bioactive compounds from plant material. Most of the solvents used for the poly-phenols extraction simultaneously extract also sugars, undesirable as a component of health-promoting food. Fermentation might be a simple, cheap and efficient way of sugar elimination. In our study, black tea and goji berries, both known for their health benefits, were used and alcoholic fermentation by Saccharomyces cerevisiae was carried out to eliminate sugars. In the course of fermentation the concentration of polyphenols, L-theanine and carotenoids was evaluated in order to verify the preservation of selected bioactive compounds. Decreases in sugar content, formation of ethanol and yeasts growth were monitored during fermentation. The fermentation of black tea decreased the sugar concentration by 84% within 6 h without decreasing total polyphenols and L-theanine contents. Goji berry fermentation yielded a sugars decrease of 87% within 24 h, without decrease in poly-phenol content. However, carotenoid content was reduced by 17%. The study showed that fermentation was an effective way to decrease sugar content in plant extracts, and therefore it might be a pertinent step to concentrate bioactives.

  19. Spine interbody implants: material selection and modification, functionalization and bioactivation of surfaces to improve osseointegration.

    Science.gov (United States)

    Rao, Prashanth J; Pelletier, Matthew H; Walsh, William R; Mobbs, Ralph J

    2014-05-01

    The clinical outcome of lumbar spinal fusion is correlated with achievement of bony fusion. Improving interbody implant bone on-growth and in-growth may enhance fusion, limiting pseudoarthrosis, stress shielding, subsidence and implant failure. Polyetheretherketone (PEEK) and titanium (Ti) are commonly selected for interbody spacer construction. Although these materials have desirable biocompatibility and mechanical properties, they require further modification to support osseointegration. Reports of extensive research on this topic are available in biomaterial-centric published reports; however, there are few clinical studies concerning surface modification of interbody spinal implants. The current article focuses on surface modifications aimed at fostering osseointegration from a clinician's point of view. Surface modification of Ti by creating rougher surfaces, modifying its surface topography (macro and nano), physical and chemical treatment and creating a porous material with high interconnectivity can improve its osseointegrative potential and bioactivity. Coating the surface with osteoconductive materials like hydroxyapatite (HA) can improve osseointegration. Because PEEK spacers are relatively inert, creating a composite by adding Ti or osteoconductive materials like HA can improve osseointegration. In addition, PEEK may be coated with Ti, effectively bio-activating the coating. PMID:24890288

  20. Main chain acid-degradable polymers for the delivery of bioactive materials

    Science.gov (United States)

    Frechet, Jean M. J.; Standley, Stephany M.; Jain, Rachna; Lee, Cameron C.

    2012-03-20

    Novel main chain acid degradable polymer backbones and drug delivery systems comprised of materials capable of delivering bioactive materials to cells for use as vaccines or other therapeutic agents are described. The polymers are synthesized using monomers that contain acid-degradable linkages cleavable under mild acidic conditions. The main chain of the resulting polymers readily degrade into many small molecules at low pH, but remain relatively stable and intact at physiological pH. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and other sites of inflammation.

  1. Wettable Ceramic-Based Drained Cathode Technology for Aluminum Electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    J.N. Bruggeman; T.R. Alcorn; R. Jeltsch; T. Mroz

    2003-01-09

    The goal of the project was to develop the ceramic based materials, technology, and necessary engineering packages to retrofit existing aluminum reduction cells in order to reduce energy consumption required for making primary aluminum. The ceramic materials would be used in a drained cathode configuration which would provide a stable, molten aluminum wetted cathode surface, allowing the reduction of the anode-cathode distance, thereby reducing the energy consumption. This multi-tasked project was divided into three major tasks: (1) Manufacturing and laboratory scale testing/evaluation of the ceramic materials, (2) Pilot scale testing of qualified compositions from the first task, and (3) Designing, retrofitting, and testing the ceramic materials in industrial cells at Kaiser Mead plant in Spokane, Washington. Specific description of these major tasks can be found in Appendix A - Project Scope. Due to the power situation in the northwest, the Mead facility was closed, thus preventing the industrial cell testing.

  2. Influence of bioactive materials used on the dentin surface whitened with carbamide peroxide 16%

    Directory of Open Access Journals (Sweden)

    Helena Burlamaqui Pinheiro

    2010-06-01

    Full Text Available This study investigated the influence of bioactive materials on the dentin surface whitened. MATERIAL AND METHODS: Three bovine teeth were shaped into three dentin wafers. Each wafer was then sectioned, into six dentin slices. One slice from each tooth was distributed into one of 6 groups: 1.CG = control group (distilled water; 2.WT = whitening treatment; 3.WT + MI Paste Plus, applied once a day; 4.WT + Relief ACP30, applied once a day for 30 mintes; 5.WT + Relief ACP60, applied once a day for 60 minutes; 6.WT + Biosilicate®, applied once a week. All groups were treated over 14 days. RESULTS: CG presented all dentinal tubules occluded by smear layer; WT group was observed all dentinal tubules opened. In the groups 3, 4 and 6, tubules were occluded. Group 5, dentinal tubules were completely occluded by mineral deposits. CONCLUSION: The use of bioactive materials immediately after whitening treatment can reduce or even avoid the demineralization effect of whitening and avoid exposing dentinal tubules.

  3. Transition from Bioinert to Bioactive Material by Tailoring the Biological Cell Response to Carboxylated Nanocellulose.

    Science.gov (United States)

    Hua, Kai; Rocha, Igor; Zhang, Peng; Gustafsson, Simon; Ning, Yi; Strømme, Maria; Mihranyan, Albert; Ferraz, Natalia

    2016-03-14

    This work presents an insight into the relationship between cell response and physicochemical properties of Cladophora cellulose (CC) by investigating the effect of CC functional group density on the response of model cell lines. CC was carboxylated by electrochemical TEMPO-mediated oxidation. By varying the amount of charge passed through the electrolysis setup, CC materials with different degrees of oxidation were obtained. The effect of carboxyl group density on the material's physicochemical properties was investigated together with the response of human dermal fibroblasts (hDF) and human osteoblastic cells (Saos-2) to the carboxylated CC films. The introduction of carboxyl groups resulted in CC films with decreased specific surface area and smaller total pore volume compared with the unmodified CC (u-CC). While u-CC films presented a porous network of randomly oriented fibers, a compact and aligned fiber pattern was depicted for the carboxylated-CC films. The decrease in surface area and total pore volume, and the orientation and aggregation of the fibers tended to augment parallel to the increase in the carboxyl group density. hDF and Saos-2 cells presented poor cell adhesion and spreading on u-CC, which gradually increased for the carboxylated CC as the degree of oxidation increased. It was found that a threshold value in carboxyl group density needs be reached to obtain a carboxylated-CC film with cytocompatibility comparable to commercial tissue culture material. Hence, this study demonstrates that a normally bioinert nanomaterial can be rendered bioactive by carefully tuning the density of charged groups on the material surface, a finding that not only may contribute to the fundamental understanding of biointerface phenomena, but also to the development of bioinert/bioactive materials. PMID:26886265

  4. A new bio-active glass ceramic

    International Nuclear Information System (INIS)

    Since 1960 fine ceramics such as alumina have been used side by side with metallic materials for bone and joint replacement. They have high mechanical strength and are free from corrosion problem faced by metals. However they don't bond to the natural living bone and hence are called bio-inactive. This was followed by the development of bio-active glasses and glass-ceramics which bond to the natural bone but have low mechanical strength. In the present work a new bio-active glass-ceramic, based on CaO-SiO/sub 2/-P/sub 2/O/sub 3/-MgO composition, has been developed which has mechanical strength compared to that of a bio-inactive glass ceramic and also bonds strongly to the natural bone. X-ray diffraction analysis reveals wollastanite and apatite phases in the glass ceramic. A new bio-active cement has also been developed which can be used to join broken pieces of bone or by itself at a filler. (author)

  5. Application of Bioactive Natural Materials-based Products on Five Women's Diseases.

    Science.gov (United States)

    Yi, Sun Shin; Hwang, Eunmi; Baek, Hye Kyung; Kim, Tae-Hee; Lee, Hae-Hyeog; Jun, Hyun Sik; Kim, Sung-Jo

    2015-12-01

    Women's health has been threatened by various diseases mainly including heart disease, breast cancer, osteoporosis, depression, and autoimmune disease. But development of medication for these diseases has been restricted by high development costs and low success rates. Herein the attempt to develop valid bioactive materials from a traditional natural material has been made. Resveratrol has been reported to be effective in treatment of breast cancer and heart disease. Goji berry has received attention as a natural based therapeutic material to treat a diabetes, cardiovascular disease, and osteoporosis. Leonurus family has been reported to be effective particularly in pregnant women due to high contents of vitamin as well as stimulation of uterine contraction. Annona family has effects such as anti-anxiety, anticonvulsant and recently it is proposed to be as a therapeutic material to cure depression based on its strong antidepressant effect. Shiraia bambusicola has been utilized to cure angiogenesis-related disease from ancient China and furthermore recently it was proved to be effective in rheumatoid arthritis. Getting an understanding of utilization of these traditional natural materials not only enhances the interest in development of therapeutic materials for preventing and treating various women's diseases, but also makes it possible to develop novel therapeutic materials. PMID:26793675

  6. Novel bioactive materials: silica aerogel and hybrid silica aerogel/pseudowollastonite

    Directory of Open Access Journals (Sweden)

    Reséndiz-Hernández, P. J.

    2014-10-01

    Full Text Available Silica aerogel and hybrid silica aerogel/pseudowollastonite materials were synthesized by controlled hydrolysis of tetraethoxysilane (TEOS using also methanol (MeOH and pseudowollastonite particles. The gels obtained were dried using a novel process based on an ambient pressure drying. Hexane and hexamethyl-disilazane (HMDZ were the solvents used to chemically modify the surface. In order to assess bioactivity, aerogels, without and with pseudowollastonite particles, were immersed in simulated body fluid (SBF for 7 and 14 days. The hybrid silica aerogel/pseudowollastonite showed a higher bioactivity than that observed for the single silica aerogel. However, as in both cases a lower bioactivity was observed, a biomimetic method was also used to improve it. In this particular method, samples of both materials were immersed in SBF for 7 days followed by their immersion in a more concentrated solution (1.5 SBF for 14 days. A thick and homogeneous bonelike apatite layer was formed on the biomimetically treated materials. Thus, bioactivity was successfully improved even on the aerogel with no pseudowollastonite particles. As expected, the hybrid silica aerogel/pseudowollastonite particles showed a higher bioactivity.Se sintetizaron aerogel de sílice y aerogel híbrido de sílice/partículas de pseudowollastonita por hidrólisis controlada de tetraetoxisilano (TEOS usando metanol (MeOH y partículas de pseudowollastonita. Los geles obtenidos se secaron utilizando un novedoso proceso basado en una presión de secado ambiental. Hexano y hexametil-disilazano fueron los solventes usados para modificar químicamente la superficie. Para evaluar la bioactividad, los aerogeles con y sin partículas de pseudowollastonita se sumergieron en un fluido fisiológico simulado (SBF por 7 y 14 días. El aerogel híbrido de sílice/partículas de pseudowollastonita mostró más alta bioactividad que la observada por el aerogel solo. Sin embargo, en ambos casos, se

  7. Atmospheric-Pressure Cold Plasmas Used to Embed Bioactive Compounds in Matrix Material for Active Packaging of Fruits and Vegetables

    Science.gov (United States)

    Fernandez, Sulmer; Pedrow, Patrick; Powers, Joseph; Pitts, Marvin

    2009-10-01

    Active thin film packaging is a technology with the potential to provide consumers with new fruit and vegetable products-if the film can be applied without deactivating bioactive compounds.Atmospheric pressure cold plasma (APCP) processing can be used to activate monomer with concomitant deposition of an organic plasma polymerized matrix material and to immobilize a bioactive compound all at or below room temperature.Aims of this work include: 1) immobilize an antimicrobial in the matrix; 2) determine if the antimicrobial retains its functionality and 3) optimize the reactor design.The plasma zone will be obtained by increasing the voltage on an electrode structure until the electric field in the feed material (argon + monomer) yields electron avalanches. Results will be described using Red Delicious apples.Prospective matrix precursors are vanillin and cinnamic acid.A prospective bioactive compound is benzoic acid.

  8. Optimization on Extraction Engineering of the Anti - inflammatory Bioactive Materials from Ainsliaea Fragrans Champ

    Directory of Open Access Journals (Sweden)

    Yang Jie

    2016-01-01

    Full Text Available Ainsliaea fragrans Champ.(A.fragrans is a traditional Chinese herbal, phenolic compounds was the major anti - inflammatory bioactive constituents. To improve the bioavailability and enhanced the curative effect of A.fragrans, the anti - inflammatory effect of phenolic acids and the “non-active” group of control vectors constitute a new biomedical material, which is of great significance to the treatment of diseases inflammation. Hence, in this thesis, regarding the total phenolic acid transfer rate as the indicator, L9(34 orthogonal design was used to optimize the extraction process of total Phenolic acid from A.fragrans by reflux extraction method on solvent dosage, extraction times and extraction time.The optimal extraction technology was as follows: 15 times of water volume, reflux extraction 3 times, extraction time 60 min. The result of pharmacological activity indicated anti-inflammatory effect: 95% ethanol extraction > water extraction > 30% ethanol extraction > 60% ethanol extraction.

  9. Evaluation of the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects

    Directory of Open Access Journals (Sweden)

    Vishakha Grover

    2013-01-01

    Full Text Available Background: Bioactive ceramic fillers are synthetic materials which have shown the potential to enhance bone formation. The purpose of this study was to evaluate the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects. Materials and Methods: Fourteen intrabony defects in twelve systemically healthy subjects having moderate to severe chronic periodontitis were evaluated after bone grafting with bioactive ceramic filler for a period of 6 months. Clinical and radiographic evaluations were made at baseline, at 3 and 6 months following surgery. Results: Mean radiographic defect fill of 64.76% (2.49±0.5 mm was observed in 6 months, which was statistically significant. A statistically significant relative attachment level gain of 2.71±1.13 mm and probing pocket depth reduction of 4.21±1.18 mm was recorded at the end of the study. A significant decrease in mobility and gingival index was observed. Conclusions: Bioactive glass is an efficacious treatment option for the reconstruction of intrabony periodontal defects as it led to statistically significant improvements in the clinical and radiographic parameters.

  10. Low temperature synthesis of bioactive materials Síntese de materiais bioativos a baixas temperaturas

    Directory of Open Access Journals (Sweden)

    L. C. Bandeira

    2011-06-01

    Full Text Available Bioactive materials possess properties that allow them to interact with natural tissues to induce reactions that favor the development and regeneration of those tissues. In this study, silica was prepared by the sol-gel method, using tetraethylorthosilicate as the precursor. The calcium and phosphor sources used here were calcium ethoxy and phosphoric acid, respectively, in ethanol solvent. The solid obtained was dried at 50 ºC. In vitro bioactivity assays were performed by soaking the materials in simulated body fluid (SBF. The samples were characterized by transmission electron microscopy (TEM, thermal analysis and photoluminescence. TEM images of the samples before contact with SBF revealed amorphous aggregates and after 12 days in SBF showed two phases, one amorphous with large quantities of Si and O, and the other a crystalline phase whose composition contained Ca and P. The electron diffraction pattern showed a planar distance of 2.86 Å, corresponding to 2θ = 32.2º. This was ascribed to hydroxyapatite. The Eu III was used as structural probe. The relative band intensity correspondent the transition 5D0 → 7F2 / 5D0 → 7F1 showed a high symmetry surrounding the Eu III ion. These materials, produced by the sol-gel route, open up new possibilities for obtaining bioactive biomaterials for medical applications.Os materiais bioativos apresentam propriedades que permitem a sua interação com um tecido de origem natural podendo induzir a sua regeneração. Neste estudo, o método sol-gel foi utilizado para a preparação de sílica dopada com íons cálcio e fósforo, partindo dos precursores tetraetilortosilicato, etóxido de cálcio e ácido fosfórico em etanol como solvente. O sólido obtido foi seco a 50 ºC. Ensaios de bioatividade foram realizados in vitro em uma solução que simula o fluido corpóreo (SBF. As amostras foram caracterizadas por microscopia eletrônica de transmissão (MET, análise térmica e fotoluminescência. As

  11. Bending strength of glass-ceramics based on 3CaO.P2O5-SiO2-MgO glass system

    International Nuclear Information System (INIS)

    In this work, the Modulus of Rupture of bioactive glass-ceramic based on 3CaO.P2O5-SiO2-MgO system was investigated, aiming its use in bone-restorations. The mechanical property was correlated with microstructural and crystallographic features of this material. High-purity starting-powders, CaCO3, SiO2, MgO, Ca (H2PO4).H2O, were used in this study. The powders were mixed in a stoichiometric ratio, using planetary ball-mill. The suspensions were dried, sieved and melted at 1600 deg C, for 4h. The casting ones were cooled quickly until annealing temperature 700 deg C, in which remained for 2h, with controlled cooling-rate until ambient temperature. Bulks of glass were heat-treated with temperatures varying between 700 deg C and 1100 deg C, for 4h, being after that, cooled at 3 deg C/min. Bioactive glass and glass-ceramic were characterized by HRXRD (high resolution X-ray diffraction), where whitlockite was main phase. The microstructure was analyzed by scanning electronic microscopy. Modulus of Rupture was determined by four-point bending testing using specimens of 1.5 x 2 x 25 mm and glasses presented strength near to 70MPa, while glass ceramics treated at 975 deg C-4h, presented bending strength of 120MPa. (author)

  12. Determination of bioactive and potentially toxic compounds in food: raw material analysis and shelf life evaluation

    OpenAIRE

    Verardo, Vito

    2009-01-01

    "Bioactive compounds" are extranutritional constituents that typically occur in small quantities in food. They are being intensively studied to evaluate their effects on health. Bioactive compounds include both water soluble compounds, such as phenolics, and lipidic substances such as n-3 fatty acids, tocopherols and sterols. Phenolic compounds, tocopherols and sterols are present in all plants and have been studied extensively in cereals, nuts and oil. n-3 fatty acids are pres...

  13. Effect of anodization and alkali-heat treatment on the bioactivity of titanium implant material (an in vitro study)

    Science.gov (United States)

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Objective: This study was aimed to assess the effect of anodized and alkali-heat surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V) after immersion in Hank's solution for 7 days. Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (five for each), five samples were anodized in 1M H3PO4 at constant voltage value of 20 v and another five samples were alkali-treated in 5 M NaOH solution for 25 min at temperature 60°C followed by heat treatment at 600°C for 1 h. All samples were then immersed in Hank's solution for 7 days to assess the effect of surface modifications on the bioactivity of titanium alloy. The different treated surfaces and control one were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transformation infra-red spectroscopy. Statistical analysis was performed with PASW Statistics 18.0® (Predictive Analytics Software). Results: Anodization of Ti-alloy samples (Group B) led to the formation of bioactive titanium oxide anatase phase and PO43− group on the surface. The alkali-heat treatment of titanium alloy samples (Group C) leads to the formation of bioactive titania hydrogel and supplied sodium ions. The reaction between the Ti sample and NaOH alkaline solution resulted in the formation of a layer of amorphous sodium titania on the Ti surface, and this layer can induce apatite deposition. Conclusions: The surface roughness and surface chemistry had an excellent ability to induce bioactivity of titanium alloy. The anodization in H3PO4 produced anatase titanium oxide on the surface with phosphate originated from electrolytes changed the surface topography and allowed formation of calcium-phosphate. PMID:27382532

  14. Application of magnetron sputtering for producing bioactive ceramic coatings on implant materials

    Indian Academy of Sciences (India)

    J Z Shi; C Z Chen; H J Yu; S J Zhang

    2008-11-01

    Radio frequency (RF) magnetron sputtering is a versatile deposition technique that can produce thin, uniform, dense calcium phosphate coatings. In this paper, principle and character of magnetron sputtering is introduced, and development of the hydroxyapatite and its composite coatings application is reviewed. In addition, influence of heat treatment on magnetron sputtered coatings is discussed. The heat treated coatings have been shown to exhibit bioactive behaviour both in vivo and in vitro. At last, the future application of the bioactive ceramic coating deposited by magnetron sputtering is mentioned.

  15. Separators - Technology review: Ceramic based separators for secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram; Bazhenov, Vasilii; Meyer, Dirk C. [Technische Universität Bergakademie Freiberg, Institut für Experimentelle Physik, Leipziger Str. 23, 09596 Freiberg (Germany); Schilm, Jochen [Fraunhofer-Institut für Keramische Technologien und Systeme IKTS, Winterbergstraße 28, 01277 Dresden (Germany); Leisegang, Tilmann [Fraunhofer-Technologiezentrum Halbleitermaterialien THM, Am St.-Niclas-Schacht 13, 09599 Freiberg (Germany)

    2014-06-16

    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ('Energiewende') was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based

  16. Separators - Technology review: Ceramic based separators for secondary batteries

    International Nuclear Information System (INIS)

    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ('Energiewende') was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators

  17. Using plant bioactive materials to control gastrointestinal tract helminths in livestock

    OpenAIRE

    Torres-Acosta, J.F.J.; Hoste, Herve; Salem, A. Z. M.; Chan-Pérez, J.I.

    2012-01-01

    Use of plants containing bioactive compounds to control of helminths in the gastrointestinaltract, either as phytotherapeutic or nutraceutical options, has been a growing researcharea in recent years. We discuss strategies to identify viable candidate compounds within vitro and in vivo anthelmintic properties. We also discuss factors which may influencein vitro and in vivo results, and difficulties of translating in vitro results to in vivo conditionsare considered using experiences with smal...

  18. Immobilization of Trypsin in Lignocellulosic Waste Material to Produce Peptides with Bioactive Potential from Whey Protein

    Directory of Open Access Journals (Sweden)

    Juliana Cristina Bassan

    2016-05-01

    Full Text Available In this study, trypsin (Enzyme Comission 3.4.21.4 was immobilized in a low cost, lignocellulosic support (corn cob powder—CCP with the goal of obtaining peptides with bioactive potential from cheese whey. The pretreated support was activated with glyoxyl groups, glutaraldehyde and IDA-glyoxyl. The immobilization yields of the derivatives were higher than 83%, and the retention of catalytic activity was higher than 74%. The trypsin-glyoxyl-CCP derivative was thermally stable at 65 °C, a value that was 1090-fold higher than that obtained with the free enzyme. The trypsin-IDA-glyoxyl-CCP and trypsin-glutaraldehyde-CCP derivatives had thermal stabilities that were 883- and five-fold higher, respectively, then those obtained with the free enzyme. In the batch experiments, trypsin-IDA-glyoxyl-CCP retained 91% of its activity and had a degree of hydrolysis of 12.49%, while the values for trypsin-glyoxyl-CCP were 87% and 15.46%, respectively. The stabilized derivative trypsin-glyoxyl-CCP was also tested in an upflow packed-bed reactor. The hydrodynamic characterization of this reactor was a plug flow pattern, and the kinetics of this system provided a relative activity of 3.04 ± 0.01 U·g−1 and an average degree of hydrolysis of 23%, which were suitable for the production of potentially bioactive peptides.

  19. Bioactive substances

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.

    Chemistry related to certain bioactive molecules, from Indian Ocean Region, developed into drugs or which served as models for the synthesis of more effective bioactive substances or in use in fundamental studies of physiological and biochemical...

  20. Ceramics based on titanium nitride and silicon nitride sintered by SPS-method

    Science.gov (United States)

    Sivkov, A. A.; Gerasimov, D. Yu; Evdokimov, A. A.

    2015-10-01

    The dependences of the microstructure and physical and mechanical properties of ceramic mixtures Si3N4/TiN in the full range of mass ratios of the components. Was also investigated directly, and the process of sintering occurring during a physical or chemical processes, in particular, has been obtained and the hardness of the material density on the ratio of the conductive titanium nitride phase and a silicon nitride insulating phase with values above and below the percolation threshold. Also obtained was pure ceramics based on titanium nitride with high physical-mechanical characteristics (H = 21.5 GPa).

  1. Two natural glucomannan polymers, from Konjac and Bletilla, as bioactive materials for pharmaceutical applications.

    Science.gov (United States)

    Wang, Yu; Liu, Jingjing; Li, Qiu; Wang, Yitao; Wang, Chunming

    2015-01-01

    Next-generation biomaterials are expected to possess both desirable mechanical features and unique biological functions. Recently, two plant-derived glucomannans (GMs)-Konjac glucomannan (KGM) and the polysaccharide of Bletilla striata (BSP)-have emerged as new sources for development of biomaterials. They have been fabricated into drug delivery vehicles and wound healing dressings in varying shapes and sizes, and demonstrated strong gelling properties, high biocompatibility and remarkable convenience for processing and modification. Notably, they demonstrate bioactivities such as response to enzymes produced in special biological niches and/or affinity for carbohydrate receptors on specific cells. All these mechanical and biological advantages suggest these two GMs have great potential for future development and broader application in various biomedical and pharmaceutical fields. PMID:25214219

  2. Ceramics based on calcium pyrophosphate nanopowders

    Directory of Open Access Journals (Sweden)

    Tatiana V. Safronova

    2013-03-01

    Full Text Available Present work is aimed at the fabrication of resorbable bioceramics based on calcium pyrophosphate (CPP from the synthesized powders of amorphous hydrated calcium pyrophosphate (AHCPP. Amorphous hydratedcalcium pyrophosphate in the form of nanopowders was precipitated from Ca(NO3 2 and (NH4 4P2O7 solutions at room temperature in the presence of PO3– ions. Crystalline CPP powder was fabricated from AHCPP by its thermal decomposition at 600 °C and consisted of β- and α- phase. Small particles, with the size less than 200 nm, were formed promoting sintering of the ceramic material. The final sample, sintered at 900 °C, exhibits microstructure with submicron grains, apparent density of 87% of theoretical density (TD and demonstrates tensile strength of 70 MPa.

  3. Comparison of sealing ability of bioactive bone cement, mineral trioxide aggregate and Super EBA as furcation repair materials: A dye extraction study

    Directory of Open Access Journals (Sweden)

    Janani Balachandran

    2013-01-01

    Settings and Design: In vitro, dye extraction study. Materials and Methods: Forty mandibular molars were randomly divided according to the material used to repair perforation: Group I-MTA, Group II-bioactive bone cement, Group III-Super EBA, Group IV-Control (furcation left unrepaired. All samples were subject to ortho grade and retrograde methylene blue dye challenge followed by dye extraction with 65% nitric acid. Samples were then analyzed using Ultra violet (UV Visible Spectrophotometer. Statistical Analysis Used: One way analysis of variance (ANOVA, Tukey-Kramer Multiple Comparisons Test. Results: MTA and bioactive bone cement showed almost similar and lower absorbance values in comparison to Super EBA. Conclusions: Bioactive bone cement provi ded an excellent seal for furcal perforation repair and at the same time it provided comfortable handling properties, which could overcome the potential disadvantages as faced with MTA.

  4. Research Progress of Bioactive Glasses and Composite Materials%生物玻璃及其复合材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    周智华; 阮建明; 邹俭鹏; 周忠诚; 申雄军

    2005-01-01

      生物玻璃已成为材料科学、生物化学以及分子生物学的交叉学科,由于生物玻璃具有生物活性等特点,在组织工程支架材料、骨科、牙科、中耳、癌症治疗和药物载体等方面的应用前景可观。生物玻璃主要由Si、Na、Ca以及P的氧化物组成。本文综述了生物玻璃的应用、生物活性、制备、与无机材料和有机材料形成复合材料的研究进展,分析了通过将生物玻璃与陶瓷、纤维、涂层以及可降解聚合物的复合使生物玻璃材料增强、增韧等方法的优、缺点,并指出了生物玻璃今后的发展方向。%  Bioactive glasses have been studied through intercrossing of the science of materials, biology and biochemistry. Their applications are promising in dental, bone repairing and substituting and bone tissue engineering because of good bioactivity and biocompatibility. The bioactive glasses consist of silica and sodium, calcium and phosphate oxides in very specific ranges. The application, bioactivity, preparation and composite materials of bioactive glasses have been reviewed. The advantage and shortcoming of the methods of bioactive glass materials reinforced and toughed with ceramics, fiber, coat and composite materials were discussed, and the trend of development and the problems were also presented.

  5. Additive effects in UV and radiation grafting and curing processes of value in immobilization of bioactive materials

    International Nuclear Information System (INIS)

    The scope of UV and ionizing radiation grafting techniques for the immobilization of bioactive materials is discussed. The principle of the method is outlined. This involves copolymerization of a monomer containing an appropriate functional group to a backbone polymer, then attachment of the reagent by subsequent chemical reactions. Novel additives which lower the total radiation dose in grafting have been discovered and their value in immobilization processes assessed. A theory for this additive effect in grafting is proposed. Methods for speeding up these radiation processes for immobilization involving sensitized UV and electron beam (EB) curing reactions are considered. The advantages of the curing technique for immobilization are summarized. Examples of typical enzymes immobilized by the above radiation processes are given. (author). 23 refs, 11 tabs

  6. Bioactivity of degradable polymer sutures coated with bioactive glass.

    Science.gov (United States)

    Bretcanu, Oana; Verné, Enrica; Borello, Luisa; Boccaccini, Aldo R

    2004-08-01

    Novel bioactive materials have been prepared by coating violet resorbable Vicryl sutures with a bioactive glass powder derived from a co-precipitation method. Two techniques have been chosen for the composite preparation: pressing the sutures in a bed of glass powder and slurry-dipping of sutures in liquid suspensions of bioactive glass powders. The uniformity and thickness of the coatings obtained by the two methods were compared. The bioactivity of the sutures with and without bioactive glass coating was tested by soaking in an inorganic acellular simulated body fluid (SBF). The composite sutures were characterised by XRD, SEM and FTIR analyses before and after soaking in SBF solution to assess the formation of hydroxyapatite on their surfaces, which is a qualitative measure of their bioactivity. The possible use of bioactive sutures to produce tissue engineering scaffolds and as reinforcement of resorbable calcium phosphates is discussed. PMID:15477741

  7. Development of prototypes of bioactive packaging materials based on immobilized bacteriophages for control of growth of bacterial pathogens in foods.

    Science.gov (United States)

    Lone, Ayesha; Anany, Hany; Hakeem, Mohammed; Aguis, Louise; Avdjian, Anne-Claire; Bouget, Marina; Atashi, Arash; Brovko, Luba; Rochefort, Dominic; Griffiths, Mansel W

    2016-01-18

    Due to lack of adequate control methods to prevent contamination in fresh produce and growing consumer demand for natural products, the use of bacteriophages has emerged as a promising approach to enhance safety of these foods. This study sought to control Listeria monocytogenes in cantaloupes and RTE meat and Escherichia coli O104:H4 in alfalfa seeds and sprouts under different storage conditions by using specific lytic bacteriophage cocktails applied either free or immobilized. Bacteriophage cocktails were introduced into prototypes of packaging materials using different techniques: i) immobilizing on positively charged modified cellulose membranes, ii) impregnating paper with bacteriophage suspension, and iii) encapsulating in alginate beads followed by application of beads onto the paper. Phage-treated and non-treated samples were stored for various times and at temperatures of 4°C, 12°C or 25°C. In cantaloupe, when free phage cocktail was added, L. monocytogenes counts dropped below the detection limit of the plating technique (format (immobilized or non-immobilized (free)). In conclusion, the developed phage-based materials demonstrated significant antimicrobial effect, when applied to the artificially contaminated foods, and can be used as prototypes for developing bioactive antimicrobial packaging materials capable of enhancing the safety of fresh produce and RTE meat. PMID:26490649

  8. Evaluation of nystatin containing chitosan hydrogels as potential dual action bio-active restorative materials: in vitro approach.

    Science.gov (United States)

    Perchyonok, V Tamara; Reher, Vanessa; Zhang, Shengmiao; Basson, Nicki; Grobler, Sias

    2014-01-01

    Healing is a specific biological process related to the general phenomenon of growth and tissue regeneration and is a process generally affected by several systemic conditions or as detrimental side-effects of chemotherapy- and radiotherapy-induced inflammation of the oral mucosa. The objectives of this study is to evaluate the novel chitosan based functional drug delivery systems, which can be successfully incorporated into "dual action bioactive restorative materials", capable of inducing in vitro improved wound healing prototype and containing an antibiotic, such as nystatin, krill oil as an antioxidant and hydroxyapatite as a molecular bone scaffold, which is naturally present in bone and is reported to be successfully used in promoting bone integration when implanted as well as promoting healing. The hydrogels were prepared using a protocol as previously reported by us. The physico-chemical features, including surface morphology (SEM), release behaviors, stability of the therapeutic agent-antioxidant-chitosan, were measured and compared to the earlier reported chitosan-antioxidant containing hydrogels. Structural investigations of the reactive surface of the hydrogel are reported. Release of nystatin was investigated for all newly prepared hydrogels. Bio-adhesive studies were performed in order to assess the suitability of these designer materials. Free radical defense capacity of the biomaterials was evaluated using established in vitro model. The bio-adhesive capacity of the materials in the in vitro system was tested and quantified. It was found that the favorable synergistic effect of free radical built-in defense mechanism of the new functional materials increased sustainable bio-adhesion and therefore acted as a functional multi-dimensional restorative material with potential application in wound healing in vitro. PMID:25459982

  9. Bioactive β-carbolines norharman and harman in traditional and novel raw materials for chicory coffee.

    Science.gov (United States)

    Wojtowicz, Elżbieta; Zawirska-Wojtasiak, Renata; Przygoński, Krzysztof; Mildner-Szkudlarz, Sylwia

    2015-05-15

    The β-carboline compounds norharman and harman exhibit neuroactive activity in the human body. Chicory coffee has proved to be a source of β-carboline compounds. This study assessed the norharman and harman contents of traditional and novel raw materials for the production of chicory coffee, as well as in samples of chicory coffee with novel additives. The highest content of the β-carbolines among the traditional raw materials was recorded in roasted sugar beet (2.26 μg/g), while roasting the chicory caused a 25-fold increase in the content of norharman in this raw material (from 0.05 to 1.25 μg/g). In novel raw materials not subjected to the action of high temperature, β-carboline was not detected. Among the roasted novel raw materials, the highest contents of harman and norharman were found in artichokes. High harman levels were also recorded in roasted chokeberry. PMID:25577081

  10. Evaluation of Nystatin Containing Chitosan Hydrogels as Potential Dual Action Bio-Active Restorative Materials: in Vitro Approach

    Directory of Open Access Journals (Sweden)

    V. Tamara Perchyonok

    2014-11-01

    Full Text Available Healing is a specific biological process related to the general phenomenon of growth and tissue regeneration and is a process generally affected by several systemic conditions or as detrimental side-effects of chemotherapy- and radiotherapy-induced inflammation of the oral mucosa. The objectives of this study is to evaluate the novel chitosan based functional drug delivery systems, which can be successfully incorporated into “dual action bioactive restorative materials”, capable of inducing in vitro improved wound healing prototype and containing an antibiotic, such as nystatin, krill oil as an antioxidant and hydroxyapatite as a molecular bone scaffold, which is naturally present in bone and is reported to be successfully used in promoting bone integration when implanted as well as promoting healing. The hydrogels were prepared using a protocol as previously reported by us. The physico-chemical features, including surface morphology (SEM, release behaviors, stability of the therapeutic agent-antioxidant-chitosan, were measured and compared to the earlier reported chitosan-antioxidant containing hydrogels. Structural investigations of the reactive surface of the hydrogel are reported. Release of nystatin was investigated for all newly prepared hydrogels. Bio-adhesive studies were performed in order to assess the suitability of these designer materials. Free radical defense capacity of the biomaterials was evaluated using established in vitro model. The bio-adhesive capacity of the materials in the in vitro system was tested and quantified. It was found that the favorable synergistic effect of free radical built-in defense mechanism of the new functional materials increased sustainable bio-adhesion and therefore acted as a functional multi-dimensional restorative material with potential application in wound healing in vitro.

  11. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties

    Energy Technology Data Exchange (ETDEWEB)

    Dziadek, Michal, E-mail: dziadek@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Menaszek, Elzbieta, E-mail: elzbieta.menaszek@uj.edu.pl [Jagiellonian University, Collegium Medicum, Department of Cytobiology, 9 Medyczna St., 30-688 Krakow (Poland); Zagrajczuk, Barbara, E-mail: b.zagrajczuk@gmail.com [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Pawlik, Justyna, E-mail: pawlikj@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland); Cholewa-Kowalska, Katarzyna, E-mail: cholewa@agh.edu.pl [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Glass Technology and Amorphous Coatings, 30 Mickiewicza Ave., 30-059 Krakow (Poland)

    2015-11-01

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21 vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO{sub 2}–CaO–P{sub 2}O{sub 5} system differing in SiO{sub 2} and CaO contents were applied (mol%): S2: 80SiO{sub 2}, 16CaO, 4P{sub 2}O{sub 5} and A2: 40SiO{sub 2}, 54CaO, 6P{sub 2}O{sub 5}. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37 °C for 56 weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~ 67° for 21A2-PCL compared to ~ 78° for pure PCL) and also makes AS surface more hydrophobic (~ 94° for 21S2-PCL compared to ~ 86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38 GPa for pure PCL, 0.90 GPa for 12A2-PCL to 1.31 GPa for 21A2-PCL), which also depends on

  12. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties

    International Nuclear Information System (INIS)

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21 vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO2–CaO–P2O5 system differing in SiO2 and CaO contents were applied (mol%): S2: 80SiO2, 16CaO, 4P2O5 and A2: 40SiO2, 54CaO, 6P2O5. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37 °C for 56 weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~ 67° for 21A2-PCL compared to ~ 78° for pure PCL) and also makes AS surface more hydrophobic (~ 94° for 21S2-PCL compared to ~ 86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38 GPa for pure PCL, 0.90 GPa for 12A2-PCL to 1.31 GPa for 21A2-PCL), which also depends on SBG chemical composition. After 56-week degradation test

  13. Fixation of bioactive calcium alkali phosphate on Ti6Al4V implant material with femtosecond laser pulses

    Science.gov (United States)

    Symietz, Christian; Lehmann, Erhard; Gildenhaar, Renate; Koter, Robert; Berger, Georg; Krüger, Jörg

    2011-04-01

    Bone implants made of metal, often titanium or the titanium alloy Ti6Al4V, need to be surface treated to become bioactive. This enables the formation of a firm and durable connection of the prosthesis with the living bone. We present a new method to uniformly cover Ti6Al4V with a thin layer of ceramics that imitates bone material. These calcium alkali phosphates, called GB14 and Ca10, are applied to the metal by dip coating of metal plates into an aqueous slurry containing the fine ceramic powder. The dried samples are illuminated with the 790 nm radiation of a pulsed femtosecond laser. If the laser fluence is set to a value just below the ablation threshold of the ceramic (ca. 0.4 J/cm 2) the 30 fs laser pulses penetrate the partly transparent ceramic layer of 20-40 μm thickness. The remaining laser fluence at the ceramic-metal interface is still high enough to generate a thin metal melt layer leading to the ceramic fixation on the metal. The laser processing step is only possible because Ti6Al4V has a lower ablation threshold (between 0.1 and 0.15 J/cm 2) than the ceramic material. After laser treatment in a fluence range between 0.1 and 0.4 J/cm 2, only the particles in contact with the metal withstand a post-laser treatment (ultrasonic cleaning). The non-irradiated rest of the layer is washed off. In this work, we present results of a successful ceramic fixation extending over larger areas. This is fundamental for future applications of arbitrarily shaped implants.

  14. Fixation of bioactive calcium alkali phosphate on Ti6Al4V implant material with femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Symietz, Christian; Lehmann, Erhard; Gildenhaar, Renate; Koter, Robert; Berger, Georg [BAM Bundesanstalt fuer Materialforschung und -pruefung, Unter den Eichen 87, D-12205 Berlin (Germany); Krueger, Joerg, E-mail: joerg.krueger@bam.de [BAM Bundesanstalt fuer Materialforschung und -pruefung, Unter den Eichen 87, D-12205 Berlin (Germany)

    2011-04-01

    Bone implants made of metal, often titanium or the titanium alloy Ti6Al4V, need to be surface treated to become bioactive. This enables the formation of a firm and durable connection of the prosthesis with the living bone. We present a new method to uniformly cover Ti6Al4V with a thin layer of ceramics that imitates bone material. These calcium alkali phosphates, called GB14 and Ca10, are applied to the metal by dip coating of metal plates into an aqueous slurry containing the fine ceramic powder. The dried samples are illuminated with the 790 nm radiation of a pulsed femtosecond laser. If the laser fluence is set to a value just below the ablation threshold of the ceramic (ca. 0.4 J/cm{sup 2}) the 30 fs laser pulses penetrate the partly transparent ceramic layer of 20-40 {mu}m thickness. The remaining laser fluence at the ceramic-metal interface is still high enough to generate a thin metal melt layer leading to the ceramic fixation on the metal. The laser processing step is only possible because Ti6Al4V has a lower ablation threshold (between 0.1 and 0.15 J/cm{sup 2}) than the ceramic material. After laser treatment in a fluence range between 0.1 and 0.4 J/cm{sup 2}, only the particles in contact with the metal withstand a post-laser treatment (ultrasonic cleaning). The non-irradiated rest of the layer is washed off. In this work, we present results of a successful ceramic fixation extending over larger areas. This is fundamental for future applications of arbitrarily shaped implants.

  15. Comparative evaluation of the biological properties of bone bioimplants Tutoplast® and bioactive ceramic material "Syntekost" when implanted in the middle ear in the experiment

    Directory of Open Access Journals (Sweden)

    Kravchenko S.V.

    2014-09-01

    Full Text Available Background. Trepanation cavity formed during sanitizing operation subsequently leads to a recurrence of inflammation in the middle ear cavity. A special importance in mastoidoplastics is to eliminate the postoperative cavity. One of the current problems is to create an alternative plastic material that could be used for healing of the bone defect with the newly formed bone tissue without causing further injury to the patient. Objective. The purpose of this study was to investigate and compare the features of reparative processes of bone implant Tutoplast® and bioactive ceramic material "Sintekost" as well as to assess the reaction of the inner ear to the materials which were replanted into the tympanic bullae of guinea pigs while creating an experimental model of antromastoidotomy. Methods. Experimental studies were carried out on 72 male guinea pigs of 300-400 g. Depending on the used plastic material animals were divided into 3 groups. Studies were performed on the left ear of the animal, the right ear was used as a control. Animals were withdrawn from the experiment on the 14th, 30th, 90th, 120th, 330th day. To evaluate the results of the study common histological methods were used. Results. After implanting of bioactive ceramic material "Sintekost" into tympanic bullae of guinea pigs signs of resorption of the material were mild and these processes were not always accompanied by the formation of bone tissue. The newly formed bone trabeculae were not observed until 90 day. After implanting cancellous bone crumbs "Tutoplast" into tympanic bullae of guinea pigs the initiation of osteogenesis was observed on the one hand and the resorption of bone fragments on the other. This resulted in formation of newly formed bone tissue whose volume gradually grew, filling the cavity of the tympanic bullae in that area. Implant "Tutoplast" possessed osteoplastic properties, which contributed to the growth of bone, acting as a matrix on which bone islands

  16. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties.

    Science.gov (United States)

    Dziadek, Michal; Menaszek, Elzbieta; Zagrajczuk, Barbara; Pawlik, Justyna; Cholewa-Kowalska, Katarzyna

    2015-11-01

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO2-CaO-P2O5 system differing in SiO2 and CaO contents were applied (mol%): S2: 80SiO2, 16CaO, 4P2O5 and A2: 40SiO2, 54CaO, 6P2O5. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37°C for 56weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~67° for 21A2-PCL compared to ~78° for pure PCL) and also makes AS surface more hydrophobic (~94° for 21S2-PCL compared to ~86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38GPa for pure PCL, 0.90GPa for 12A2-PCL to 1.31GPa for 21A2-PCL), which also depends on SBG chemical composition. After 56-week degradation test, considerably higher

  17. Bending strength of glass-ceramics based on 3CaO.P{sub 2}O{sub 5}-SiO{sub 2}-MgO glass system; Resistencia a fratura de vitroceramicos do sistema 3CaO.P{sub 2}O{sub 5}-SiO{sub 2}-MgO

    Energy Technology Data Exchange (ETDEWEB)

    Daguano, J.K.M.F.; Suzuki, P.A.; Santos, C. [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Escola de Engenharia de Lorena. Dept. de Engenharia de Materiais; Fernandes, M.H.V. [Universidade de Aveiro (UAveiro/CECICO), Aveiro (Portugal). Centro de Investigacao em Materiais Ceramicos e Compositos. Dept. de Engenharia Ceramica e do Vidro; Elias, C.N. [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Lab. de Biomateriais

    2009-07-01

    In this work, the Modulus of Rupture of bioactive glass-ceramic based on 3CaO.P{sub 2}O{sub 5}-SiO{sub 2}-MgO system was investigated, aiming its use in bone-restorations. The mechanical property was correlated with microstructural and crystallographic features of this material. High-purity starting-powders, CaCO{sub 3}, SiO{sub 2}, MgO, Ca (H{sub 2}PO{sub 4}).H{sub 2}O, were used in this study. The powders were mixed in a stoichiometric ratio, using planetary ball-mill. The suspensions were dried, sieved and melted at 1600 deg C, for 4h. The casting ones were cooled quickly until annealing temperature 700 deg C, in which remained for 2h, with controlled cooling-rate until ambient temperature. Bulks of glass were heat-treated with temperatures varying between 700 deg C and 1100 deg C, for 4h, being after that, cooled at 3 deg C/min. Bioactive glass and glass-ceramic were characterized by HRXRD (high resolution X-ray diffraction), where whitlockite was main phase. The microstructure was analyzed by scanning electronic microscopy. Modulus of Rupture was determined by four-point bending testing using specimens of 1.5 x 2 x 25 mm and glasses presented strength near to 70MPa, while glass ceramics treated at 975 deg C-4h, presented bending strength of 120MPa. (author)

  18. Evaluation of Nystatin Containing Chitosan Hydrogels as Potential Dual Action Bio-Active Restorative Materials: in Vitro Approach

    OpenAIRE

    V. Tamara Perchyonok; Vanessa Reher; Shengmiao Zhang; Nicki Basson; Sias Grobler

    2014-01-01

    Healing is a specific biological process related to the general phenomenon of growth and tissue regeneration and is a process generally affected by several systemic conditions or as detrimental side-effects of chemotherapy- and radiotherapy-induced inflammation of the oral mucosa. The objectives of this study is to evaluate the novel chitosan based functional drug delivery systems, which can be successfully incorporated into “dual action bioactive restorative materials”, capable of inducing i...

  19. Coatings of titanium substrates with xCaO · (1 - x)SiO2 sol-gel materials: characterization, bioactivity and biocompatibility evaluation.

    Science.gov (United States)

    Catauro, M; Papale, F; Bollino, F

    2016-01-01

    The objective of this study has been to develop low temperature sol-gel coatings to modify the surface of commercially pure titanium grade 4 (a material generally used in dental application) and to evaluate their bioactivity and biocompatibility on the substrate. Glasses of composition expressed by the following general formula xCaO · (1 - x)SiO2 (0.0characterized and a microstructural analysis of the coatings obtained was performed using scanning electron microscopy (SEM). The potential applications of the coatings in the biomedical field were evaluated by bioactivity and biocompatibility tests. The coated titanium was immersed in simulated body fluid (SBF) for 21 days and the hydroxyapatite deposition on its surface was subsequently evaluated via SEM-EDXS analysis, as an index of bone-bonding capability. To investigate cell-material interactions, mouse embryonic fibroblast cells (3T3) were seeded onto the specimens and the cell viability was evaluated by a WST-8 assay. PMID:26478379

  20. Bio-active glass air-abrasion has the potential to remove resin composite restorative material selectively

    International Nuclear Information System (INIS)

    The aims of this study were to assess: (a) the chemistry, morphology and bioactivity of bio-active glass (BAG) air-abrasive powder, (b) the effect of three air-abrasion operating parameters: air pressure, powder flow rate (PFR) and the abrasive powder itself, on the selective removal of resin composite and (c) the required “time taken”. BAG abrasive particles were characterised using scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR). Standardised resin composite restorations created within an enamel analogue block (Macor™) in vitro, were removed using air-abrasion undersimulated clinical conditions. 90 standardised cavities were scanned before and after resin composite removal using laser profilometry and the volume of the resulting 3D images calculated. Multilevel linear model was used to identify the significant factors affecting Macor™ removal. BAG powder removed resin composite more selectively than conventional air-abrasion alumina powder using the same operating parameters (p < 0.001) and the effect of altering the unit's operating parameters was significant (p < 0.001). In conclusion, BAG powder is more efficient than alumina in the selective removal of resin composite particularly under specific operating parameters, and therefore may be recommended clinically as a method of preserving sound enamel structure when repairing and removing defective resin composite restorations.

  1. Bio-active glass air-abrasion has the potential to remove resin composite restorative material selectively

    Science.gov (United States)

    Milly, Hussam; Andiappan, Manoharan; Thompson, Ian; Banerjee, Avijit

    2014-06-01

    The aims of this study were to assess: (a) the chemistry, morphology and bioactivity of bio-active glass (BAG) air-abrasive powder, (b) the effect of three air-abrasion operating parameters: air pressure, powder flow rate (PFR) and the abrasive powder itself, on the selective removal of resin composite and (c) the required “time taken”. BAG abrasive particles were characterised using scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR). Standardised resin composite restorations created within an enamel analogue block (Macor™) in vitro, were removed using air-abrasion undersimulated clinical conditions. 90 standardised cavities were scanned before and after resin composite removal using laser profilometry and the volume of the resulting 3D images calculated. Multilevel linear model was used to identify the significant factors affecting Macor™ removal. BAG powder removed resin composite more selectively than conventional air-abrasion alumina powder using the same operating parameters (p < 0.001) and the effect of altering the unit's operating parameters was significant (p < 0.001). In conclusion, BAG powder is more efficient than alumina in the selective removal of resin composite particularly under specific operating parameters, and therefore may be recommended clinically as a method of preserving sound enamel structure when repairing and removing defective resin composite restorations.

  2. Influence of bioactive material coating of Ti dental implant surfaces on early healing and osseointegration of bone

    International Nuclear Information System (INIS)

    The dental implant surface type is one of many factors that determine the long-term clinical success of implant restoration. The implant surface consists of bioinert titanium oxide, but recently coatings with bioactive calcium phosphate ceramics have often been used on Ti implant surfaces. Bio-active surfaces are known to significantly improve the healing time of the human bone around the inserted dental implant. In this study, we characterized two types of coated implant surfaces by scanning electron microscopy, energy dispersive spectrometry, and surface roughness testing. The effect of surface modification on early bone healing was then tested by using the rabbit tibia model to measure bone-to-implant contact ratios and removal torque values. These modified surfaces showed different characteristics in terms of surface topography, chemical composition, and surface roughness. However, no significant differences were found in the bone-to-implant contact and the resistance to removal torque between these surfaces. Both the coated implants may induce similar favorable early bone responses in terms of the early functioning and healing of dental implants even though they differed in their surface characteristics.

  3. Bio-active glass air-abrasion has the potential to remove resin composite restorative material selectively

    Energy Technology Data Exchange (ETDEWEB)

    Milly, Hussam [Biomaterials, Biomimetics and Biophotonics Research Group, Kings College London Dental Institute at Guy' s Hospital, King' s Health Partners, London (United Kingdom); Andiappan, Manoharan [Unit of Dental Public Health, Kings College London Dental Institute at Guy' s Hospital, King' s Health Partners, London (United Kingdom); Thompson, Ian [Biomaterials, Biomimetics and Biophotonics Research Group, Kings College London Dental Institute at Guy' s Hospital, King' s Health Partners, London (United Kingdom); Banerjee, Avijit, E-mail: avijit.banerjee@kcl.ac.uk [Biomaterials, Biomimetics and Biophotonics Research Group, Kings College London Dental Institute at Guy' s Hospital, King' s Health Partners, London (United Kingdom); Unit of Conservative Dentistry, King' s College London Dental Institute at Guy' s Hospital, King' s Health Partners, London (United Kingdom)

    2014-06-01

    The aims of this study were to assess: (a) the chemistry, morphology and bioactivity of bio-active glass (BAG) air-abrasive powder, (b) the effect of three air-abrasion operating parameters: air pressure, powder flow rate (PFR) and the abrasive powder itself, on the selective removal of resin composite and (c) the required “time taken”. BAG abrasive particles were characterised using scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR). Standardised resin composite restorations created within an enamel analogue block (Macor™) in vitro, were removed using air-abrasion undersimulated clinical conditions. 90 standardised cavities were scanned before and after resin composite removal using laser profilometry and the volume of the resulting 3D images calculated. Multilevel linear model was used to identify the significant factors affecting Macor™ removal. BAG powder removed resin composite more selectively than conventional air-abrasion alumina powder using the same operating parameters (p < 0.001) and the effect of altering the unit's operating parameters was significant (p < 0.001). In conclusion, BAG powder is more efficient than alumina in the selective removal of resin composite particularly under specific operating parameters, and therefore may be recommended clinically as a method of preserving sound enamel structure when repairing and removing defective resin composite restorations.

  4. Influence of bioactive material coating of Ti dental implant surfaces on early healing and osseointegration of bone

    Energy Technology Data Exchange (ETDEWEB)

    Yeo, In-Sung [Seoul National University, Seoul (Korea, Republic of); Min, Seung-Ki [Seoul National University Dental Hospital, Seoul (Korea, Republic of); An, Young-Bai [Osstem Implant Co., Ltd., Busan (Korea, Republic of)

    2010-12-15

    The dental implant surface type is one of many factors that determine the long-term clinical success of implant restoration. The implant surface consists of bioinert titanium oxide, but recently coatings with bioactive calcium phosphate ceramics have often been used on Ti implant surfaces. Bio-active surfaces are known to significantly improve the healing time of the human bone around the inserted dental implant. In this study, we characterized two types of coated implant surfaces by scanning electron microscopy, energy dispersive spectrometry, and surface roughness testing. The effect of surface modification on early bone healing was then tested by using the rabbit tibia model to measure bone-to-implant contact ratios and removal torque values. These modified surfaces showed different characteristics in terms of surface topography, chemical composition, and surface roughness. However, no significant differences were found in the bone-to-implant contact and the resistance to removal torque between these surfaces. Both the coated implants may induce similar favorable early bone responses in terms of the early functioning and healing of dental implants even though they differed in their surface characteristics.

  5. Preparation and characterization of Li$_2$O–CaO–Al$_2$O$_3$–P$_2$O$_5$–SiO$_2$ glasses as bioactive material

    Indian Academy of Sciences (India)

    HIMANSHU TRIPATHI; AREPALLI SAMPATH KUMAR; S P SINGH

    2016-04-01

    The aim of the present investigation was to study the role of Al$_2$O$_3$ in the Li$_2$O–CaO–P$_2$O$_5$–SiO$_2$ bioactive glass for improving the bioactivity and other physico-mechanical properties of glass. A comparative studyon structural and physico-mechanical properties and bioactivity of glasses were reported. The structural properties of glasses were investigated by X-ray diffraction, Fourier transform infrared spectrometry, scanning electronmicroscopy and the bioactivity of the glasses was evaluated by in vitro test in simulated body fluid (SBF). Density, compressive strength, Vickers hardness and ultrasonic wave velocity of glass samples were measured to investigatephysical and mechanical properties. Results indicated that partial molar replacement of Li$_2$O by Al$_2$O$_3$ resulted in a significant increase in mechanical properties of glasses. In vitro studies of samples in SBF had shown that the pH of the solution increased after immersion of samples during the initial stage and then after reaching maxima it decreased with the increase in the immersion time. In vitro test in SBF indicated that the addition of Al$_2$O$_3$ up to 1.5 mol% resulted in an increase in bioactivity where as further addition of Al$_2$O$_3$ caused a decrease in bioactivity of the samples. The biocompatibility of these bioactive glass samples was studied using human osteoblast (MG-63) cell lines. The results obtained suggested that Li$_2$O–CaO–Al$_2$O$_3$–P$_2$O$_5$–SiO$_2$-based bioactive glasses containing alumina would be potential materials for biomedical applications.

  6. Bioactive glasses: Frontiers and challenges

    Directory of Open Access Journals (Sweden)

    Larry L. Hench

    2015-11-01

    Full Text Available Bioactive glasses were discovered in 1969 and provided for the first time an alternative to nearly inert implant materials. Bioglass formed a rapid, strong and stable bond with host tissues. This article examines the frontiers of research crossed to achieve clinical use of bioactive glasses and glass-ceramics. In the 1980’s it was discovered that bioactive glasses could be used in particulate form to stimulate osteogenesis, which thereby led to the concept of regeneration of tissues. Later, it was discovered that the dissolution ions from the glasses behaved like growth factors, providing signals to the cells. This article summarizes the frontiers of knowledge crossed during four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglass®. The four eras are: a discovery; b clinical application; c tissue regeneration; and d innovation. Questions still to be answered for the fourth era are included to stimulate innovation in the field and exploration of new frontiers that can be the basis for a general theory of bioactive stimulation of regeneration of tissues and application to numerous clinical needs.

  7. Influence of the polymer amount on bioactivity and biocompatibility of SiO{sub 2}/PEG hybrid materials synthesized by sol–gel technique

    Energy Technology Data Exchange (ETDEWEB)

    Catauro, M., E-mail: michelina.catauro@unina2.it [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29, 81031 Aversa (Italy); Bollino, F.; Papale, F. [Department of Industrial and Information Engineering, Second University of Naples, Via Roma 29, 81031 Aversa (Italy); Gallicchio, M.; Pacifico, S. [Department of Environmental Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Via Vivaldi 43, 81100 Caserta (Italy)

    2015-03-01

    SiO{sub 2}/PEG organic–inorganic hybrid materials, which differ in polyethylene glycol (PEG) content, were synthesized by sol–gel technique and the characterization of their structure and biological properties was carried out in order to evaluate the possible use in biomedical field. FT-IR spectroscopy detected that the two components of the hybrids (SiO{sub 2} and PEG) are linked by hydrogen bonds between the Si–OH groups of the inorganic phase and the terminal alcoholic groups and/or the ethereal oxygen atoms in the repeating units of polymer. X-ray diffraction analysis ascertained the amorphous nature of the gels and the observation of their morphology by SEM microscopy confirmed that the interpenetration of the two phases (organic and inorganic) occurs on nanometric scale. The biological characterization was carried out as a function of the polymer amount to study its influence on material behavior. The results showed that the synthesized materials were bioactive and biocompatible. The formation of a hydroxyapatite layer, indeed, was observed on their surface by SEM/EDX analysis after soaking in simulated body fluid. Moreover, the biocompatibility of SiO{sub 2}/PEG hybrids was assessed performing MTT and SRB cytotoxicity tests on fibroblast cell NIH 3T3 after 24 and 48 h of exposure, as well as Trypan Blue dye exclusion test. The response to the presence of the investigated materials was positive. The cell growth and proliferation showed dependence on polymer amount and time of exposure to the material extracts. Therefore, the obtained results are encouraging for the use of the obtained hybrids in dental or orthopedic applications. - Highlights: • SiO{sub 2}/PEG hybrid biomaterials synthesized by sol–gel method at various PEG percentages • Chemical and morphological characterization of hybrid materials • Chemical interactions between inorganic and organic components • Biological characterizations with MTT and SRB cytotoxicity tests

  8. Influence of the polymer amount on bioactivity and biocompatibility of SiO2/PEG hybrid materials synthesized by sol–gel technique

    International Nuclear Information System (INIS)

    SiO2/PEG organic–inorganic hybrid materials, which differ in polyethylene glycol (PEG) content, were synthesized by sol–gel technique and the characterization of their structure and biological properties was carried out in order to evaluate the possible use in biomedical field. FT-IR spectroscopy detected that the two components of the hybrids (SiO2 and PEG) are linked by hydrogen bonds between the Si–OH groups of the inorganic phase and the terminal alcoholic groups and/or the ethereal oxygen atoms in the repeating units of polymer. X-ray diffraction analysis ascertained the amorphous nature of the gels and the observation of their morphology by SEM microscopy confirmed that the interpenetration of the two phases (organic and inorganic) occurs on nanometric scale. The biological characterization was carried out as a function of the polymer amount to study its influence on material behavior. The results showed that the synthesized materials were bioactive and biocompatible. The formation of a hydroxyapatite layer, indeed, was observed on their surface by SEM/EDX analysis after soaking in simulated body fluid. Moreover, the biocompatibility of SiO2/PEG hybrids was assessed performing MTT and SRB cytotoxicity tests on fibroblast cell NIH 3T3 after 24 and 48 h of exposure, as well as Trypan Blue dye exclusion test. The response to the presence of the investigated materials was positive. The cell growth and proliferation showed dependence on polymer amount and time of exposure to the material extracts. Therefore, the obtained results are encouraging for the use of the obtained hybrids in dental or orthopedic applications. - Highlights: • SiO2/PEG hybrid biomaterials synthesized by sol–gel method at various PEG percentages • Chemical and morphological characterization of hybrid materials • Chemical interactions between inorganic and organic components • Biological characterizations with MTT and SRB cytotoxicity tests • Biocompatibility improvement with

  9. Zn and Sr incorporated 64S bioglasses: Material characterization, in-vitro bioactivity and mesenchymal stem cell responses

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xiaoli [College of Materials Science and Engineering, Sichuan University, Chengdu (China); Meng, Guolong [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu (China); Wang, Shanling [Analytical & Testing Center, Sichuan University, Chengdu 610064 (China); Wu, Fang, E-mail: fwu@scu.edu.cn [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu (China); Huang, Wanxia, E-mail: huangwanxia@126.com [College of Materials Science and Engineering, Sichuan University, Chengdu (China); Gu, Zhongwei [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu (China)

    2015-07-01

    Essential element like Zn or Sr is known to play an important role in bone remodeling process. In this study, we have used the sol–gel process to synthesize the Zn (2%) and Sr (5%) doped 64S bioglasses (BGs, 64SiO{sub 2}–5P{sub 2}O{sub 5}–31CaO, mol.%), alone and co-doped. The synthesized glasses were characterized by XRD, FTIR and STEM. For biological evaluation, the effects of Zn and Sr incorporation on the in vitro bioactivity of the synthesized BGs were studied using the simulated body fluid (SBF) soaking. The proliferation and differentiation (ALP, OCN) of rat mesenchymal stem cells (MSCs) on these BGs were studied using CCK-8 and ELISA analyses. The results indicated that Zn had been uniformly incorporated into the bioglass, and demonstrated a stimulating effect on apatite-like layer formation, MSC proliferation and differentiation. On the other hand, most of Sr appeared to form a secondary crystal phase with extremely high solubility in SBF, showing an enhancing effect only in MSC differentiation but not in proliferation, as well as an inhibitory effect on apatite-like layer formation. The different dissolution behaviors of Sr and Zn ions seemed to have a strong correlation with the different apatite-like layer formation capabilities and the cellular responses of Zn and Sr containing BGs. - Highlights: • We synthesized the Zn (2%) and Sr (5%) doped 64S bioglasses, alone and co-doped. • Most of Sr appeared to form a secondary crystal phase. • Sr demonstrated a stimulating effect only on MSC differentiation. • We suggest likely different stimulating mechanisms of Sr and Zn toward MSC responses.

  10. Stability of Chokeberry Bioactive Polyphenols during Juice Processing and Stabilization of a Polyphenol-Rich Material from the By-Product

    Directory of Open Access Journals (Sweden)

    Diana Behsnilian

    2012-09-01

    Full Text Available Chokeberries (Aronia melanocarpa are nowadays believed to exhibit potential cardioprotective and antidiabetic effects principally due to their high content in bioactive phenolic compounds. The stability of the phenolic compounds was studied during different stages of a juice production line and a method for the valorization of pomace was evaluated. Samples were taken from a commercial juice production plant, extracted and analyzed for phenolic constituents and antioxidant potential. Prototypes of functional food ingredients were produced from the pomace by wet milling and micro-milling. Alongside juice processing, the contents of phenolic berry constituents did not vary to a great extent and the overall antioxidant activity increased by about 34%. A high quality juice and a by-product still rich in polyphenols resulted from the process. The phenolic compounds content and the overall antioxidant activity remained stable when milling and micro-milling the pomace. During coarse milling, extractability of total phenolic compounds increased significantly (40% to 50%. Nanosized materials with averaged particle sizes (x50,0 of about 90 nm were obtained by micro-milling. These materials showed significantly enhanced extractability of total phenolic compounds (25% and total phenolic acid (30%, as well as antioxidant activity (35%, with unchanged contents of total procyanidins and anthocyanins contents.

  11. Magnetoelectric Effect in Ceramics Based on Bismuth Ferrite

    Science.gov (United States)

    Jartych, Elżbieta; Pikula, Tomasz; Kowal, Karol; Dzik, Jolanta; Guzdek, Piotr; Czekaj, Dionizy

    2016-04-01

    Solid-state sintering method was used to prepare ceramic materials based on bismuth ferrite, i.e., (BiFeO3)1 - x -(BaTiO3) x and Bi1 - x Nd x FeO3 solid solutions and the Aurivillius Bi5Ti3FeO15 compound. The structure of the materials was examined using X-ray diffraction, and the Rietveld method was applied to phase analysis and structure refinement. Magnetoelectric coupling was registered in all the materials using dynamic lock-in technique. The highest value of magnetoelectric coupling coefficient α ME was obtained for the Bi5Ti3FeO15 compound ( α ME ~ 10 mVcm-1 Oe-1). In the case of (BiFeO3)1 - x -(BaTiO3) x and Bi1 - x Nd x FeO3 solid solutions, the maximum α ME is of the order of 1 and 2.7 mVcm-1 Oe-1, respectively. The magnitude of magnetoelectric coupling is accompanied with structural transformation in the studied solid solutions. The relatively high magnetoelectric effect in the Aurivillius Bi5Ti3FeO15 compound is surprising, especially since the material is paramagnetic at room temperature. When the materials were subjected to a preliminary electrical poling, the magnitude of the magnetoelectric coupling increased 2-3 times.

  12. Ceramic based lightweight composites with extreme dynamic strength

    International Nuclear Information System (INIS)

    On the basis of several years experiments in development of high performance technical ceramics and in investigation of hetero-modulus and hetero-viscous materials and ceramic matrix composites the authors successfully developed a new family of ceramic reinforced lightweight composites with extreme dynamic strength. To obtain these lightweight composites first the matrix materials were developed from different sort of sintered ceramics with high porosity and after the prepared items were re-sintered using reactive sintering methods or were impregnated with nanoparticles of Si3N4, SiAlON ceramics or light metal alloys having excellent mechanical strength and properties. Where it was necessary the pores and material structures of ceramic matrix materials anchored excellent wetting for a wide range of metal alloys, so it was possible to develop several types of ceramic reinforced hetero-modulus light metal composites with extreme dynamic strength of different density. In this work the authors present the c-Si3N4 diamond particles reinforced corundum matrix composite shield plate structures and some of the specially developed low density ceramic foams and high porosity ceramic matrix materials for lightweight metallic composites

  13. Properties of ceramics based on cerium dioxide with crystalline filaments

    International Nuclear Information System (INIS)

    Problems of the increase of thermal resistance of ceramics on the basis of cerium dioxide with the interduction of filamentous crystals (FC) of CeO2 and MgO have been considered. It is established that FC of MgO and CeO2 are dissolved in the matrix, foAming fine oblong pores, promoting relaxation of thermal strains and preventing crack propagation, which increases the material thermal resistance

  14. Metal-Supported SOFC with Ceramic-Based Anode

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Klemensø, Trine; Persson, Åsa Helen;

    2011-01-01

    Metal-supported solid oxide fuel cells have shown promise to offer several potential advantages over conventional anode (Ni-YSZ) supported cells, such as increased resistance against mechanical and thermal stresses and a reduction in materials cost. The purpose of this work is to illustrate how t......), zirconia-free anode, in a planar metal-supported SOFC concept is discussed. ©2011 COPYRIGHT ECS - The Electrochemical Society...

  15. Bioactivity of bioresorbable composite based on bioactive glass and poly-L-lactide

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhi-hua; RUAN Jian-ming; ZOU Jian-peng; ZHOU Zhong-cheng; SHEN Xiong-jun

    2007-01-01

    Bioactive and bioresorbable composite was fabricated by a solvent evaporation technique using poly-L-lactide(PLLA) and bioactive glass (average particle size: 6.8 μm). Bioactive glass granules are homogeneously distributed in the composite with microcrack structure. The formation of hydroxyapatite(HA) on the composite in simulated body fluid(SBF) was analyzed by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), X-ray diffraction(XRD), and Raman spectra. Rod-like HA crystals deposit on the surface of PLLA/bioactive glass composite after soaking for 3 d. Both rod-like crystals and HA layer form on the surface for 14 d in SBF. The high bioactivity of PLLA/bioactive glass composite indicates the potential of materials for integration with bone.

  16. Sol-gel derived porous bioactive nanocomposites: Synthesis and in vitro bioactivity

    Science.gov (United States)

    Shankhwar, Nisha; Kothiyal, G. P.; Srinivasan, A.

    2013-06-01

    Porous bioactive composites consisting of SiO2-CaO-Na2O-P2O5 bioactive glass-ceramic and synthetic water soluble polymer Polyvinylpyrrolidone [PVP (C6H9NO)n, MW˜40000 g/mol] have been synthesized by sol-gel route. As-prepared polymeric composites were characterized by X-ray diffraction (XRD) technique. Two major bone mineral phases, viz., hydroxyapatite [Ca10(PO4)6(OH)2] and wollastonite [calcium silicate (CaSiO3)] have been identified in the XRD patterns of the composites. Presence of these bone minerals indicates the bioactive nature of the composites. In vitro bioactivity tests confirm bioactivity in the porous composites. The flexibility offered by these bioactive polymer composites is advantageous for its application as implant material.

  17. Preparation and bioactivity of sol-gel macroporous bioactive glass

    Institute of Scientific and Technical Information of China (English)

    Zhihua Zhou; Jianming Ruan; Jianpeng Zou; Zhongcheng Zhou

    2008-01-01

    Bioactive glass is well known for its ability of bone regeneration, and sol-gel bioactive glass has many advantages com-pared with melt-derived bioactive glass. 3-D scaffold prepared by the sol-gel method is a promising substrate material for bone tissue engineering and large-scale bone repair. Porous sol-gel glass in the CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by the addition of stearic acid as a pore former. The diameter of the pore created by the pore former varied from 100 to 300μm. The formation of a hydroxyapatite layer on the glass was analyzed by studying the surface of the porous glass by scanning elec-tron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman spectra after they had been immersed in simulated body fluid (SBF) for some time, and the porous glass shows good bioactivity.

  18. Bioactivation of particles

    Science.gov (United States)

    Pinaud, Fabien; King, David; Weiss, Shimon

    2011-08-16

    Particles are bioactivated by attaching bioactivation peptides to the particle surface. The bioactivation peptides are peptide-based compounds that impart one or more biologically important functions to the particles. Each bioactivation peptide includes a molecular or surface recognition part that binds with the surface of the particle and one or more functional parts. The surface recognition part includes an amino-end and a carboxy-end and is composed of one or more hydrophobic spacers and one or more binding clusters. The functional part(s) is attached to the surface recognition part at the amino-end and/or said carboxy-end.

  19. Bioactive Hierarchical Structures for Genetic Control of Bone Morphogenesis

    Directory of Open Access Journals (Sweden)

    Pilar Sepulveda

    2002-09-01

    Full Text Available For thirty years it has been known that certain compositions of Na2O-CaO-P2O5-SiO 2 glasses will form a mechanically strong, chemical bond to bone. These materials have become known as bioactive glasses and the process of bonding is called bioactive fixation. Bioactive glasses are widely used clinically in the repair of bone defects. Recent research at the Imperial College Tissue Engineering Centre has now established that there is a genetic control of the cellular response to bioactive materials. Seven families of genes are up-regulated when primary human osteoblasts are exposed to the ionic dissolution products of bioactive glasses. The gene expression occurs very rapidly, within two days, and includes enhanced expression of cell cycle regulators. The consequence is rapid differentiation of the osteoblasts into a mature phenotype and formation of large three-dimensional bone nodules within six days in vitro. These cell culture results correlate with extensive human clinical results using the same bioactive material. The new genetic theory of bioactive materials provides a scientific foundation for molecular design of new generation of resorbable bioactive materials for tissue engineering and in situ tissue regeneration and repair. Application of this theory to the synthesis of bioactive foams for tissue engineering of bone is described.

  20. Current status of ceramic-based membranes for oxygen separation from air.

    Science.gov (United States)

    Hashim, Salwa Meredith; Mohamed, Abdul Rahman; Bhatia, Subhash

    2010-10-15

    There has been tremendous progress in membrane technology for gas separation, in particular oxygen separation from air in the last 20 years. It provides an alternative route to the existing conventional separation processes such as cryogenic distillation and pressure swing adsorption as well as cheaper production of oxygen with high purity. This review presents the recent advances of ceramic membranes for the separation of oxygen from air at high temperature. It covers the issues and problems with respect to the selectivity and separation performance. The paper also presents different approaches applied to overcome these challenges. The future directions of ceramic-based membranes for oxygen separation from air are also presented. PMID:20813344

  1. Preliminary study in development of glass-ceramic based on SiO2-LiO2 system, starting of different SiO2 starting powders

    International Nuclear Information System (INIS)

    In this work, lithium disilicate glass-ceramics were developed starting of the rice ash- SiO2 and Li2CO3 powders. The results were compared with glass ceramics based on the lithium disilicate obtained by commercial SiO2 powders. Glass were melted at 1580 deg C, and annealed at 850 deg C. X-Ray diffraction and scanning electron microscopy were used for characterization of the materials, and hardness and fracture toughness were evaluated using Vickers indentation method. Glasses with amorphous structure were obtained in both materials. After annealing, 'rice-ash' samples presented Li2SiO3 and residual SiO2 as crystalline phases. On the other side, commercial SiO2- Samples presented only Li2Si2O5 as crystalline phases and the better results of hardness and fracture toughness. (author)

  2. Synthesis and study of 239Pu-doped ceramics based on zircon, (Zr,Pu)Sio4, and hafnon, (Hf,Pu)SiO4

    International Nuclear Information System (INIS)

    Zircon, ZrSiO4, as well as its Hf-analogue hafnon, HfSiO4, have been proposed for use as durable Pu host phases for the immobilization of weapons grade Pu and other actinides. Four samples of Pu-doped ceramics based on the zircon and hafnon structures were synthesized through sintering in air using precursors containing 5-6 and 10 wt% 239Pu. Synthesized ceramic samples were studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), microprobe method, MCC-1 leach test at 25 and 90 deg C. Inclusions of separated a PuO2 phase in the matrix of zircon-based ceramic and presumably, (Pu,Hf)O2 phase in the hafnon-based ceramic were observed for samples obtained from precursors doped with 10 wt% Pu. No separated Pu-phases in significant amounts were identified in the matrices of both ceramics obtained from the precursors doped with 5-6 wt% Pu. It was found that normalized Pu mass losses (without correction on ceramic porosity) for samples doped with 10 wt% Pu which contain separated inclusions of PuO2 or (Pu1Hf)O2 after 14/28 days were approximately (in g/m2) - for zircon: 0.2/0.2 - at 90 deg C and 0.03/0.04 - at 25 deg C and for hafnon: 0.02/0.04 - at 90 deg C and 0.01/0.01 - at 25 deg C. The losses of Pu from samples doped with 5-6 wt% are 1-2 order of magnitude less. It was suggested that optimal amount of Pu which could be incorporated by zircon and hafnon lattices does not exceed 7 wt%. An important additional conclusion is that Pu-doped ceramic based on zircon or hafnon can be successfully fabricated excluding hot pressing method. Copyright (2001) Material Research Society

  3. Biocompatibility and Bioactivity of Magnesium Matrix Hydroxyapatite Material%镁合金基HA材料生物相容性及生物活性的研究

    Institute of Scientific and Technical Information of China (English)

    林国湘; 薛顺; 李林升; 葛丽婧

    2015-01-01

    Magnesium matrix hydroxyapatite biological composite material was prepared by electrophoretic deposition method, and the biocompatibility and biological activity of this material was discussed. Animal experiment and SBF immersion experiment were selected separately to test the biocompatibility and bioactivity. The SD rats were divided into con-trast group and implant group. The implant material surrounding tissue was taken to do Tis-sue biopsy,HE dyed and organizational analysis after a certain amount of time in the SD body. Under homeothermic condition,the biological composite material was soaked in SBF solution. After four weeks,the bioactivity of the biological composite material was evaluated by testing the growth ability of hydroxyapatite on composite material. The experiment re-sults showed that the implant material surrounding appeared tissue hyperplasia,connective tissue and new blood vessels,but no obvious tissue inflammation,no infiltrating inflammato-ry cells such as multinuclear giant cells and neutrophils cells. After the biological compos-ite material was soaked in SBF solution,a layer Bone-Like Apatite was found on its sur-face. The results showed that Magnesium matrix hydroxyapatite biological composite materi-al have no cytotoxicity,induction bone formation,good biocompatibility and bioactivity.%采用电泳沉积法制备了镁合金基羟基磷灰石表面涂层生物复合材料。利用动物体内埋植实验和SBF浸泡实验分别对复合材料生物相容性及生物活性进行研究。将SD大鼠分为对照组和植入组,植入一定的时间后,取植入物周围组织进行切片、HE染色和组织分析;将复合材料恒温浸泡于SBF溶液四周后取出,通过检测复合材料表面生长磷灰石的能力作为评价该材料的生物活性。实验结果是植入物周围出现组织增生,有结缔组织及新生血管的形成,未见明显的组织炎症反应,无多核的巨细胞、淋巴细胞和中性

  4. Bioactive berry phenolics

    OpenAIRE

    Heinonen, Marina

    2007-01-01

    Compositional data on phenolic compounds in berries has been rapidly accumulating and readily included in the national food composition data base. Among the different bioactive substances in berries, phenolic compounds including flavonoids, tannins, and phenolic acids have received considerable interest due to their effects in food and health.

  5. Study on mechanical properties in superconducting ceramics based on Bi-Sr-Ca-Cu-O doped with lead

    International Nuclear Information System (INIS)

    Investigations performed in superconducting ceramics based on Bi-Sr-Ca-Cu-O, doped with lead, according to the stoichiometric formulae Bi2-x Pbx SR2 Ca2 Cu3 Oy, demonstrated the insertion of lead alters the mechanical properties of the material,particularly the plasticity. When employing an Hardness Testing, it was observed that the sample with a lead concentration of x = 0.4 holds the highest Vickers microhardness. It was laos noticed, when using a mercury porosimeter, that on this concentration there was a drastic reduction of the volume of each pore, evincing the lead enhanced the sintering process, considering that the sample with a lead concentration of x = 0.4 holds the minimum interval in which 80% of the pores meet (0.19 a 0.79 μm). Through optical and electronic microscopy, one can notice the presence of two main phases: a phase presenting isolating properties and another with superconducting ones. A minor phase, with birefringent properties, was also observed showing its highest concentration in the sample x = 0.2. The increase in microhardness, reaching its top in sample x = 0.4, is due to the volume reduction of the phase with isolating properties (with a lower hardness, as it was observed in the polishing), for it reaches its minimum in the sample presenting the same concentration. Also through electronic microscopy, it was noted the highest microhardness in the sample x = 0.4 was not influenced by the diameter variance or by the crystal shape, since they all present the shape of lamelars plates. Chemical etching based on acetic acid and water, have been performed in order to verify the solubility of the present phases. It was observed that the phase showing birefringent properties were much more soluble than the others. It was also observed the features of sheet, product of the reaction between the acid and the sample, on the surfaces of the samples. The diameter of these decreased until the moment when in lead concentration x = 0.1 there was no more

  6. Bioactive phytochemicals in flaxseed

    OpenAIRE

    Johnsson, Pernilla

    2009-01-01

    Flaxseed (Linum usitatissimum L.) is rich in health-promoting bioactive compounds. Among plant foods, flaxseed has the highest content of lignans, mainly in the form of secoisolariciresinol diglucoside (SDG). Flaxseed oil also has a very high concentration of the essential omega-3 fatty acid alpha-linolenic acid (ALA). This thesis presents studies on both SDG and ALA. An HPLC method for quantification of SDG in hydrolysed flaxseed extracts was developed and used to compare the SDG content in ...

  7. Bioactive macroporous titanium implants highly interconnected.

    Science.gov (United States)

    Caparrós, Cristina; Ortiz-Hernandez, Mónica; Molmeneu, Meritxell; Punset, Miguel; Calero, José Antonio; Aparicio, Conrado; Fernández-Fairén, Mariano; Perez, Román; Gil, Francisco Javier

    2016-10-01

    Intervertebral implants should be designed with low load requirements, high friction coefficient and low elastic modulus in order to avoid the stress shielding effect on bone. Furthermore, the presence of a highly interconnected porous structure allows stimulating bone in-growth and enhancing implant-bone fixation. The aim of this study was to obtain bioactive porous titanium implants with highly interconnected pores with a total porosity of approximately 57 %. Porous Titanium implants were produced by powder sintering route using the space holder technique with a binder phase and were then evaluated in an in vivo study. The size of the interconnection diameter between the macropores was about 210 μm in order to guarantee bone in-growth through osteblastic cell penetration. Surface roughness and mechanical properties were analyzed. Stiffness was reduced as a result of the powder sintering technique which allowed the formation of a porous network. Compression and fatigue tests exhibited suitable properties in order to guarantee a proper compromise between mechanical properties and pore interconnectivity. Bioactivity treatment effect in novel sintered porous titanium materials was studied by thermo-chemical treatments and were compared with the same material that had undergone different bioactive treatments. Bioactive thermo-chemical treatment was confirmed by the presence of sodium titanates on the surface of the implants as well as inside the porous network. Raman spectroscopy results suggested that the identified titanate structures would enhance in vivo apatite formation by promoting ion exchange for the apatite formation process. In vivo results demonstrated that the bioactive titanium achieved over 75 % tissue colonization compared to the 40 % value for the untreated titanium. PMID:27582071

  8. EFFECTS OF INCORPORATING NATURAL MINERALS ON PRODUCTION AND BIOACTIVITY OF BIOACTIVE GLASS CERAMICS

    Directory of Open Access Journals (Sweden)

    Franco Matias Stabile

    2016-07-01

    Full Text Available Two glass-ceramics composition were produced from natural minerals. Quartzes and feldspars were pre-selected on the basis of their purities studied by X-ray diffraction (XRD and chemical analysis. Prepared compositions of glasses precursors were two different theoretical leucite (KAlSi₂O₆ /Bioglass 45S5 (L/Bg ratios. Transformations of raw materials mixtures and glass precursors were studied by differential thermal analyses. On the basis of thermal analysis results, glass ceramics were produced and characterized by XRD. Glass-ceramics were composed of two major crystalline phases, leucite and sodium calcium silicate. Bioactivity tests were performed submerging the glass-ceramics into simulated body fluid (SBF for different periods (1, 5 and 10 days. Bioactive behavior was monitored by XRD and scanning electron microscopy (SEM. Studied samples were found to be bioactive, in which hydroxyapatite layer was developed within 5 days of contact with SBF.

  9. Bioactive glass-polymer composite for experimental bone reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Aho, A.J.; Tirri, T.; Strandberg, N.; Jaakkola, T.; Naerhi, T.; Kukkonen, J. [Turku Univ. (Finland). Biomaterials Project of Turku; Seppaelae, J.; Rich, J. [Helsinki Univ. of Technology, Espoo (Finland). Dept. of Chemical Engineering

    2001-07-01

    Thermoplastic composite of bioactive glass (S53P4) and copolymer of lactones (Glepron) can be used as liquid, injectable or paste like form, as solid plugs or thin membranes for filling bone defects. This bone substitute is bioactive, osteoconductive and biocompatible resulting in bone bonding contacts between glass granules and bone in defects on the distal femur and ulna of experimental animals. Properties of the material can be adjusted by polymer chemistry. (orig.)

  10. Bioactive Titania Layer Fabricated on Metallic Biomaterials by Electrodeposition

    OpenAIRE

    Miyazaki, T.; Otsuyama, T.; Ishida, E.

    2009-01-01

    Improvement of bone integration ability of metallic biomaterials is needed for long-term stable fIxation to bone tissues. Essential prerequisite for materials to show bone-integrating bioactivity is formation of apatite layer on their surfaces in body environments. Several functional groups have potential to trigger the apatite nucleation. In the present study, we attempted fabrication of bioactive titania layer which provides Ti-OH groups effective for the apatite formation on bioinert metal...

  11. Bioactive sugar surfaces for hepatocyte cell culture

    OpenAIRE

    Ambury, Rachael

    2010-01-01

    The primary objective of this study was to identify, develop and characterise a novel bioactive surface capable of binding hepatocytes and enabling the retention of hepatocyte-specific cell function during in-vitro culture. The materials were designed to exploit a unique characteristic of hepatocyte biology, with β-galactose moieties displayed to allow cellular adhesion via the specific asialoglycoprotein receptors (ASGP-R) found on hepatocytes. Hydrogels were created by modifying a commercia...

  12. Characteristics of Carbon Material Formation on SBA-15 and Ni-SBA-15 Templates by Acetylene Decomposition and Their Bioactivity Effects

    Directory of Open Access Journals (Sweden)

    Hsiu-Mei Chiang

    2016-05-01

    Full Text Available Carbon spheres and tubes were formed from acetylene decomposition on SBA-15 and Ni-SBA-15 at 650–850 °C. At 650 °C, the decomposed carbons covered the surface of the support, and no carbon spheres and filament materials were formed. Carbon sphere formation occurred at 750 °C–850 °C; with diameters ranging from 0.8 μm–1.1 μm. For Ni-SBA-15, the diameters of the spheres and filaments were 0.8 μm and 62 nm, respectively, at 650 °C. At 750 °C, the diameter of the ball carbon materials ranged from 0.7 μm–0.8 μm, the diameter of the carbon tubes formed was 120–130 nm, and their pore diameter was 8.0 nm–11 nm. At 850 °C, the diameters of ball carbon materials and carbon tubes were similar to those of the materials at the formation temperature, 750 °C. Si, O and C were the main constituents of SBA-15; Ni-SBA-15 and carbon material formation supports. High-ring PAHs (such as BaP (five rings; IND (six rings; DBA (five rings and B[ghi]P (six rings exist in carbon materials. SBA-15 revealed insignificant cytotoxicity, but Ni-SBA-15 inhibited the proliferation of human lung cancer cells (A549. Less inhibition on cell viability and reactive oxidative species (ROS generation on A549 were determined for carbon material formation on the Ni-SBA-15 compared to the Ni-SBA-15.

  13. Review of bioactive glass: from Hench to hybrids.

    Science.gov (United States)

    Jones, Julian R

    2013-01-01

    Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics but they lag behind other bioactive ceramics in terms of commercial success. Bioactive glass has not yet reached its potential but research activity is growing. This paper reviews the current state of the art, starting with current products and moving onto recent developments. Larry Hench's 45S5 Bioglass® was the first artificial material that was found to form a chemical bond with bone, launching the field of bioactive ceramics. In vivo studies have shown that bioactive glasses bond with bone more rapidly than other bioceramics, and in vitro studies indicate that their osteogenic properties are due to their dissolution products stimulating osteoprogenitor cells at the genetic level. However, calcium phosphates such as tricalcium phosphate and synthetic hydroxyapatite are more widely used in the clinic. Some of the reasons are commercial, but others are due to the scientific limitations of the original Bioglass 45S5. An example is that it is difficult to produce porous bioactive glass templates (scaffolds) for bone regeneration from Bioglass 45S5 because it crystallizes during sintering. Recently, this has been overcome by understanding how the glass composition can be tailored to prevent crystallization. The sintering problems can also be avoided by synthesizing sol-gel glass, where the silica network is assembled at room temperature. Process developments in foaming, solid freeform fabrication and nanofibre spinning have now allowed the production of porous bioactive glass scaffolds from both melt- and sol-gel-derived glasses. An ideal scaffold for bone regeneration would share load with bone. Bioceramics cannot do this when the bone defect is subjected to cyclic loads, as they are brittle. To overcome this, bioactive glass polymer hybrids are being synthesized that have the potential to be tough, with congruent degradation of the bioactive inorganic and

  14. Reprint of: Review of bioactive glass: From Hench to hybrids.

    Science.gov (United States)

    Jones, Julian R

    2015-09-01

    Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics but they lag behind other bioactive ceramics in terms of commercial success. Bioactive glass has not yet reached its potential but research activity is growing. This paper reviews the current state of the art, starting with current products and moving onto recent developments. Larry Hench's 45S5 Bioglass® was the first artificial material that was found to form a chemical bond with bone, launching the field of bioactive ceramics. In vivo studies have shown that bioactive glasses bond with bone more rapidly than other bioceramics, and in vitro studies indicate that their osteogenic properties are due to their dissolution products stimulating osteoprogenitor cells at the genetic level. However, calcium phosphates such as tricalcium phosphate and synthetic hydroxyapatite are more widely used in the clinic. Some of the reasons are commercial, but others are due to the scientific limitations of the original Bioglass 45S5. An example is that it is difficult to produce porous bioactive glass templates (scaffolds) for bone regeneration from Bioglass 45S5 because it crystallizes during sintering. Recently, this has been overcome by understanding how the glass composition can be tailored to prevent crystallization. The sintering problems can also be avoided by synthesizing sol-gel glass, where the silica network is assembled at room temperature. Process developments in foaming, solid freeform fabrication and nanofibre spinning have now allowed the production of porous bioactive glass scaffolds from both melt- and sol-gel-derived glasses. An ideal scaffold for bone regeneration would share load with bone. Bioceramics cannot do this when the bone defect is subjected to cyclic loads, as they are brittle. To overcome this, bioactive glass polymer hybrids are being synthesized that have the potential to be tough, with congruent degradation of the bioactive inorganic and

  15. Fabrication and characterization of strontium incorporated 3-D bioactive glass scaffolds for bone tissue from biosilica.

    Science.gov (United States)

    Özarslan, Ali Can; Yücel, Sevil

    2016-11-01

    Bioactive glass scaffolds that contain silica are high viable biomaterials as bone supporters for bone tissue engineering due to their bioactive behaviour in simulated body fluid (SBF). In the human body, these materials help inorganic bone structure formation due to a combination of the particular ratio of elements such as silicon (Si), calcium (Ca), sodium (Na) and phosphorus (P), and the doping of strontium (Sr) into the scaffold structure increases their bioactive behaviour. In this study, bioactive glass scaffolds were produced by using rice hull ash (RHA) silica and commercial silica based bioactive glasses. The structural properties of scaffolds such as pore size, porosity and also the bioactive behaviour were investigated. The results showed that undoped and Sr-doped RHA silica-based bioactive glass scaffolds have better bioactivity than that of commercial silica based bioactive glass scaffolds. Moreover, undoped and Sr-doped RHA silica-based bioactive glass scaffolds will be able to be used instead of undoped and Sr-doped commercial silica based bioactive glass scaffolds for bone regeneration applications. Scaffolds that are produced from undoped or Sr-doped RHA silica have high potential to form new bone for bone defects in tissue engineering. PMID:27524030

  16. Preparation and Characterization of Bioactive Composites of Pcl/bioactive Fillers

    Science.gov (United States)

    Li, Ying; Cheah, Chi Mun; Chang, Hengky; Loh, Leonard; Kum, Adeline

    A variety of bioactive composites have been invested over the last two decades as substitute materials for diseased or damaged tissues in the human body. In this paper, bioactive composites were prepared using polycaprolactone (PCL) and hydroxyapatite (HA). The influence of micro-sized and nano-sized HA on composite properties was investigated. The nano-HA was prepared by wet chemical co-precipitation reaction method. Studies of biocomposite specimen morphology were performed by Field-emission scanning electron microscopy (SEM). XRD (X-Ray Diffraction) and DSC (Differential scanning calorimetry) were used to assess the crystal structure of HA and thermal properties of the composites, respectively. The synthesized nano-HA is found to be of high purity HA structure. The relationship between composition, structure and properties was studied. Different methods to prepare uniform composites were tried, and the outcome of this work suggests that by proper manipulation of biodegradable polymers and bioactive ceramics through material design, bioactive composites with controlled properties might be achievable.

  17. Present and future of glass-ionomers and calcium-silicate cements as bioactive materials in dentistry: Biophotonics-based interfacial analyses in health and disease

    OpenAIRE

    Watson, Timothy F; Atmeh, Amre R.; Sajini, Shara; Cook, Richard J.; Festy, Frederic

    2014-01-01

    Objective Since their introduction, calcium silicate cements have primarily found use as endodontic sealers, due to long setting times. While similar in chemistry, recent variations such as constituent proportions, purities and manufacturing processes mandate a critical understanding of service behavior differences of the new coronal restorative material variants. Of particular relevance to minimally invasive philosophies is the potential for ion supply, from initial hydration to mature set i...

  18. Surface functionalization of bioactive glasses with natural molecules of biological significance

    OpenAIRE

    Xin ZHANG

    2014-01-01

    Natural or artificial materials used for replacement or supplement the functions of living tissues, termed as biomaterials, may be bioinert (i.e. alumina and zorconia,) resorbable (i.e. tricalcium phosphate), bioactive (i.e. hydroxyapatite, bioactive glasses, and glass-ceramics) or porous for tissue ingrowth (i.e. hydroxyapatite-coated metals). Among all the biomaterials, bioactive glass and glass-ceramics are widely used in orthopedic and dental applications and are being developed for tissu...

  19. Genetic variations of Lansium domesticum Corr. accessions from Java, Sumatra and Ceram based on Random Amplified Polymorphic DNA fingerprints

    Directory of Open Access Journals (Sweden)

    KUSUMADEWI SRI YULITA

    2011-07-01

    Full Text Available Yulita KS (2011 Genetic variations of Lansium domesticum Corr. accessions from Java, Bengkulu and Ceram based on Random Amplified Polymorphic DNA fingerprints. Biodiversitas 12: 125-130. Duku (Lansium domesticum Corr. is one of popular tropical fruits in SE Asia. The spesies has three varieties, known as duku, langsat and kokosan; and duku is the most popular one for being the sweetiest fruit. Indonesia has several local varieties of duku, such as duku Condet, duku Sumber and duku Palembang. This present study aimed to assess genetic diversity of 47 accessions of duku from Java, Sumatra, and Ceram based on RAPD fingerprints. Ten RAPD’s primers were initially screened and five were selected for the analysis. These five primers (OPA 7, 13, 18, OPB 7, and OPN 12 generated 53 scorable bands with an average of 10.6 polymorphic fragment per primer. Percentage of polymorphism ranged from 16.89% (OPA 7 and OPN 12 to 24.54% (OPB 7 with an average of 20.16% polymorphism. OPB 7 at 450 bp was exclusively possessed by accession 20 (Java, OPA 18 at 500 bp was by accession 6 (Java, 550 bp by 3 clones from Bengkulu. While OPN 12 at 300 bp and OPA 13 at 450 bp were shared among the accessions. Clustering analysis was performed based on RAPD profiles using the UPGMA method. The range of genetic similarity value among accessions was 0.02-0.65 suggesting high variation of gene pool existed among accessions.

  20. Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Verné, Enrica, E-mail: enrica.verne@polito.it [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Bruno, Matteo [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Miola, Marta [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Maina, Giovanni; Bianco, Carlotta [Traumatology Orthopedics and Occupational Medicine Dept., Università di Torino, Via G. Zuretti 29, 10126 Torino (Italy); Cochis, Andrea [Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Rimondini, Lia [Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, Via G. Giusti, 9, 50121 Firenze (Italy)

    2015-08-01

    In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO{sub 2}–Na{sub 2}O–CaO–P{sub 2}O{sub 5}–FeO–Fe{sub 2}O{sub 3} and contains magnetite (Fe{sub 3}O{sub 4}) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite – HAp – layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. - Highlights: • An in vitro biological characterization was carried out on ferromagnetic and bioactive composite cements. • No release of iron was revealed in the physiological solution. • Bioactivity tests

  1. Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility

    International Nuclear Information System (INIS)

    In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO2–Na2O–CaO–P2O5–FeO–Fe2O3 and contains magnetite (Fe3O4) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite – HAp – layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. - Highlights: • An in vitro biological characterization was carried out on ferromagnetic and bioactive composite cements. • No release of iron was revealed in the physiological solution. • Bioactivity tests show hydroxyapatite precipitates on the cement

  2. LASER-INDUCED BIOACTIVITY IN DENTAL PORCELAIN MODIFIED BY BIOACTIVE GLASS

    Directory of Open Access Journals (Sweden)

    ANASTASIA BEKETOVA

    2012-12-01

    Full Text Available The aim of this study was to investigate the impact of laser-liquid-solid interaction method in the bioactivity of dental porcelain modified by bioactive glass. Forty sol-gel derived specimens were immersed in Dulbecco's Modified Eagle's Medium, 31 and 9 specimens of which were treated with Er:YAG and Nd:YAG laser respectively. Untreated specimens served as controls. Incubation of specimens followed. Bioactivity was evaluated, using Fourier Transform Infrared spectroscopy (FTIR, Scanning Electron Microscopy (SEM/Energy Dispersive Spectroscopy (EDS and Transmission Electron Microscopy (TEM. FTIR detected peaks associated with hydroxyapatite on 1 Nd:YAG- and 4 Er:YAG-treated specimens. SEM analysis revealed that Er:YAG-treated specimens were covered by granular hydroxyapatite layer, while Nd:YAG treated specimen presented growth of flake-like hydroxyapatite. TEM confirmed the results. The untreated controls presented delayed bioactivity. In conclusion, Nd:YAG and Er:YAG laser treatment of the material, under certain fluencies, accelerates hydroxyapatite formation. Nd:YAG laser treatment of specific parameters causes the precipitation of flake-like hydroxyapatite in nano-scale.

  3. Effect of crystallinity on crack propagation and mineralization of bioactive glass 45S5

    Science.gov (United States)

    Kashyap, Satadru

    Bioactive glasses are a type of ceramic material designed to be used as bioresorbable therapeutic bone implants. Thermal treatment of bioactive glass ceramics dictates many important features such as microstructure, degree of crystallinity, mechanical properties, and mineralization. This study investigates the effects of temperature, time, and heating rates on the crystallization kinetics of melt cast bioactive glass 45S5. Bulk crystallization (three dimensional crystallite formation) was found to always occur in bulk bioactive glass 45S5 irrespective of the processing conditions. A comparative study of crack paths in amorphous and crystalline phases of bioactive glass 45S5 revealed crack deflections and higher fracture resistance in partially crystallized bioactive glass. Such toughening is likely attributed to different crystallographic orientations of crystals or residual thermal mismatch strains. Furthermore, in vitro immersion testing of partially crystalline glass ceramic revealed higher adhesion capabilities of the mineralized layer formed on amorphous regions as compared to its crystalline counterpart.

  4. Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility.

    Science.gov (United States)

    Verné, Enrica; Bruno, Matteo; Miola, Marta; Maina, Giovanni; Bianco, Carlotta; Cochis, Andrea; Rimondini, Lia

    2015-08-01

    In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO2-Na2O-CaO-P2O5-FeO-Fe2O3 and contains magnetite (Fe3O4) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite - HAp - layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. PMID:26042695

  5. Bioactive proteins from pipefishes

    Institute of Scientific and Technical Information of China (English)

    E. Rethna Priya; S. Ravichandran; R. Ezhilmathi

    2013-01-01

    Objective: To screen antimicrobial potence of some pipefish species collected from Tuticorin coastal environment.Methods:Antimicrobial activity of pipefishes in methanol extract was investigated against 10 bacterial and 10 fungal human pathogenic strains.Results:Among the tested strains, in Centriscus scutatus, pipefish showed maximum zone of inhibition against Vibrio cholerae (8 mm) and minimum in the sample of Hippichthys cyanospilos against Klebseilla pneumoniae (2 mm). In positive control, maximum zone of inhibition was recorded in Vibrio cholerae (9 mm) and minimum in Klebseilla pneumoniae, and Salmonella paratyphi (5 mm). Chemical investigation indicated the presence of peptides as evidenced by ninhydrin positive spots on thin layer chromatography and presence of peptide. In SDS PAGE, in Centriscus scutatus, four bands were detected in the gel that represented the presence of proteins in the range nearly 25.8-75 kDa. In Hippichthys cyanospilos, five bands were detected in the gel that represented the presence of proteins in the range nearly 20.5-78 kDa. The result of FT-IR spectrum revealed that the pipe fishes extracts compriseed to have peptide derivatives as their predominant chemical groups.Conclusions:It can be conclude that this present investigation suggests the tested pipe fishes will be a potential source of natural bioactive compounds.

  6. 基于膜射流乳化技术的TiO2大孔陶瓷制备方法研究%Preparation of Macroporous TiO2 Ceramic Based on Membrane Jet-flow Emulsification

    Institute of Scientific and Technical Information of China (English)

    景文珩; 吴守红; 薛业建; 金万勤; 邢卫红; 徐南平

    2007-01-01

    A novel method to prepare macroporous TiO2 ceramic, based on membrane emulsification was reported.To solve the paradox between the instability of nonaqueous emulsion and long emulsification time required by the membrane emulsification, a two-stage ceramic membrane jet-flow emulsification was proposed. Discussion was conducted on the evolution of droplet size with time, which followed the Ostwald ripening theory. And a monodispersed nonaqueous emulsion with an average droplet size of 1.6μm could be prepared. Using the emulsion as a template, TiO2 ceramics with an average pore size of 1.1μm were obtained. The material could be prospectively used for preparation of catalysts, adsorbents, and membranes.

  7. Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Goudouri, O.-M. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kontonasaki, E. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Papadopoulou, L.; Kantiranis, N. [Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Lazaridis, N.K. [Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Chrissafis, K.; Chatzistavrou, X. [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Koidis, P. [School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Paraskevopoulos, K.M., E-mail: kpar@auth.gr [Physics Department, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2014-05-01

    An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

  8. Towards the synthesis of an experimental bioactive dental ceramic. Part I: Crystallinity characterization and bioactive behavior evaluation

    International Nuclear Information System (INIS)

    An attachment between the dental ceramic and the surrounding marginal tissues in fixed prosthetic restorations could eliminate secondary carries prevalence. The development of dental ceramics with apatite forming ability could provide the biological surface required for selective spread and attachment of specific cell types able to promote tissue attachment. Dental ceramics/bioactive glass composites synthesized by the sol gel method have been previously reported to develop carbonated hydroxyapatite (HCAp) in biomimetic solutions, requiring though a high amount of bioactive glass, which resulted in the compromise of their mechanical integrity. Thus, the aim of the present work was the synthesis and characterization of an experimental sol–gel derived dental ceramic with low amount of bioactive glass and the evaluation of its in vitro bioactivity. Differential thermal and thermogravimetric analysis (TG–DTA), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to evaluate the crystal structure and the in vitro apatite forming ability of the synthesized material. The results of this study indicated the successful sol–gel synthesis of an experimental dental ceramic containing low amount of bioactive glass that presented similar structural and morphological characteristics with a commercial feldspathic dental ceramic, while exhibiting in vitro bioactivity. The apatite forming ability of the experimental sol–gel derived feldspathic dental ceramic may trigger the appropriate cellular mechanisms towards the establishment of attachment with the surrounding connective tissue. This attachment could provide a barrier to oral bacteria penetration, prolonging the life expectation of the restorations. - Highlights: • Synthesis of a bioactive sol–gel dental ceramic for fixed prosthetic restorations. • The sol–gel technique promoted the crystallization of

  9. Thermoluminescence as a probe in bioactivity studies; the case of 58S sol-gel bioactive glass

    Science.gov (United States)

    Polymeris, George S.; Menti Goudouri, Ourania; Kontonasaki, Eleana; Paraskevopoulos, Konstantinos M.; Tsirliganis, Nestor C.; Kitis, George

    2011-10-01

    The formation of a carbonated hydroxyapatite (HCAp) layer on the surface of bioactive materials is the main reaction that takes place upon their immersion in physiological fluids. To date, all techniques used for the identification of this HCAp formation are rather time consuming and not well suited to detailed and rapid monitoring of changes in the bioactivity response of the material. The aim of this work is to explore the possibility of using thermoluminescence (TL) for the discrimination between different bioactive responses in the case of the 58S bioactive glass. Results provided strong indications that the 110 °C TL peak of quartz can be used effectively in the study of the bioactive behaviour of 58S bioactive glass, since it is unambiguously present in all samples and does not require deconvolution analysis. Furthermore, the intensity of the 110 °C TL peak is proven to be very sensitive to the different bioactive responses, identifying the loss of silica which takes place at the first stages of the sequence. The discontinuities of the 110 °C TL peak intensity plot versus immersion time at 8 and 1440 min provide experimental indications regarding the timescale for both the beginning of amorphous CaP formation as well as the end of crystalline hydroxyl-apatite formation respectively, while the spike in the sensitization of the 110 °C TL peak, which was observed for immersion times ranging between 20 and 40 min, could be an experimental feature indicating the beginning of the crystalline HCAp formation.

  10. Synthesis of nano-bioactive glass-ceramic powders and its in vitro bioactivity study in bovine serum albumin protein

    Science.gov (United States)

    Nabian, Nima; Jahanshahi, Mohsen; Rabiee, Sayed Mahmood

    2011-07-01

    Bioactive glasses and ceramics have proved to be able to chemically bond to living bone due to the formation of an apatite-like layer on its surface. The aim of this work was preparation and characterization of bioactive glass-ceramic by sol-gel method. Nano-bioglass-ceramic material was crushed into powder and its bioactivity was examined in vitro with respect to the ability of hydroxyapatite layer to form on the surface as a result of contact with bovine serum albumin (BSA) protein. The obtained nano-bioactive glass-ceramic was analyzed before and after contact with BSA solution. This study used scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis to examine its morphology, crystallinity and composition. The TEM images showed that the NBG particles size were 10-40 nm. Bioactivity of nanopowder was confirmed by SEM and XRD due to the presence of a rich bone-like apatite layer. Therefore, this nano-BSA-bioglass-ceramic composite material is promising for medical applications such as bone substitutes and drug carriers.

  11. Comparison of Calcium Hydroxide and Bioactive Glass after Direct Pulp Capping in Primary Teeth

    OpenAIRE

    Haghgoo, R.; N. Jalayer Naderi

    2007-01-01

    Objective: Bioactive glass is often used as a filler material for repair of dental bone defects.In different studies osteogenic potential of this material was proved, but its dentinogenesisproperty is in doubt. The purpose of this study was to evaluate the histological pulp responses of Calcium hydroxide and Bioactive glass placed directly on exposed pulp tissues.Materials and Methods: Twenty teeth to be extracted due to orthodontic reasons were selected. These teeth were divided into two gro...

  12. Bioactivity and mechanical behaviour of cobalt oxide-doped bioactive glass

    Indian Academy of Sciences (India)

    Vikash Kumar Vyas; Arepalli Sampath Kumar; Sunil Prasad; S P Singh; Ram Pyare

    2015-08-01

    Bioactive glasses are materials capable of bonding implants to tissues. 45S5 Bio-glass® is one such material capable of bonding strongly to bone within 6 weeks. It develops a hydroxy-carbonate apatite layer on the implant that is chemically and crystallographically equivalent to the mineral phase of bone. However, it suffers from a mechanical weakness and low fracture toughness due to an amorphous glass network and is not suitable for load-bearing applications. In order to improve its mechanical strength and bioactivity, the present work explores the effects of cobalt oxide additions. Bioactivity of the glass samples was assessed through their hydroxyapatite formation ability by immersing them in the simulated body fluid for different soaking periods. The formation of hydroxyapatite was confirmed by Fourier transform infrared spectrometry, pH measurement and microstructure evaluation through scanning electron microscopy. Densities and mechanical properties of the samples were found to increase considerably with an increase in the concentration of cobalt oxide.

  13. Characterisation of the bioactive behaviour of sol-gel hydroxyapatite-CaO and hydroxyapatite-CaO-bioactive glass composites

    International Nuclear Information System (INIS)

    The fabrication and characterization of sol-gel derived hydroxyapatite-calcium oxide (HAp-CaO) material is investigated focusing on the effect of the addition of a bioactive glass on the material bioactive behaviour through the fabrication of a novel HAp-CaO (70 wt.%)-bioactive glass (30 wt.%) composite material. The bioactive behaviour of the materials was assessed by immersion studies in Simulated Body Fluid (SBF) and the alterations of the materials surfaces after soaking periods in SBF were characterized by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). A brittle and weakly crystalline carbonate hydroxyapatite (HCAp) layer was found to develop on the surface of all samples, few hours after immersion in SBF, confirming the high bioactivity of the material. Alterations of the morphology of the developed HCAp layer, which led to a more compact structure, were observed on the surface of composite samples after 7 days of immersion in SBF. The presence of the CaO phase seems to accelerate the formation of HCAp, while the bioactive glass affects both the morphology and cohesion of the developed layer.

  14. Bioactive Peptides in Milk and Dairy Products: A Review

    Science.gov (United States)

    Park, Young Woo; Nam, Myoung Soo

    2015-01-01

    Functionally and physiologically active peptides are produced from several food proteins during gastrointestinal digestion and fermentation of food materials with lactic acid bacteria. Once bioactive peptides (BPs) are liberated, they exhibit a wide variety of physiological functions in the human body such as gastrointestinal, cardiovascular, immune, endocrine, and nervous systems. These functionalities of the peptides in human health and physiology include antihypertensive, antimicrobial, antioxidative, antithrombotic, opioid, anti-appetizing, immunomodulatory and mineral-binding activities. Most of the bioactivities of milk proteins are latent, being absent or incomplete in the original native protein, but full activities are manifested upon proteolytic digestion to release and activate encrypted bioactive peptides from the original protein. Bioactive peptides have been identified within the amino acid sequences of native milk proteins. Due to their physiological and physico-chemical versatility, milk peptides are regarded as greatly important components for health promoting foods or pharmaceutical applications. Milk and colostrum of bovine and other dairy species are considered as the most important source of natural bioactive components. Over the past a few decades, major advances and developments have been achieved on the science, technology and commercial applications of bioactive components which are present naturally in the milk. Although the majority of published works are associated with the search of bioactive peptides in bovine milk samples, some of them are involved in the investigation of ovine or caprine milk. The advent of functional foods has been facilitated by increasing scientific knowledge about the metabolic and genomic effects of diet and specific dietary components on human health. PMID:26877644

  15. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available BACKGROUND: Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. MATERIALS AND METHODS: The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests. RESULTS: The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony

  16. Synthesis and in vitro bioactivity of mesoporous bioactive glass scaffolds

    International Nuclear Information System (INIS)

    The main objective of the present study was to determine the effect of thermal treatment procedures (calcination temperature, heating rate and duration time) on the synthesis of SiO2-CaO-P2O5 mesoporous bioactive glass scaffolds. This is accomplished by thermogravimetric analyses, Fourier transform infrared (FTIR) absorption spectra, X-ray diffraction (XRD) and by analysis of nitrogen adsorption/desorption isotherms. In vitro bioactivity can also be assessed by the cytotoxic effect of the glasses on the NIH-3T3 cell line, and by characterization of MC-3T3-E1 cell attachment.

  17. Synthesis and in vitro bioactivity of mesoporous bioactive glass scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Shih, C.J., E-mail: cjshih@kmu.edu.tw [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chen, H.T. [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Huang, L.F. [School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Lu, P.S.; Chang, H.F. [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, I.L., E-mail: 84004@cch.org.tw [Department of Orthopaedic Surgery, Chang-Hua Christian Hospital, Changhua 500, Taiwan (China)

    2010-06-15

    The main objective of the present study was to determine the effect of thermal treatment procedures (calcination temperature, heating rate and duration time) on the synthesis of SiO{sub 2}-CaO-P{sub 2}O{sub 5} mesoporous bioactive glass scaffolds. This is accomplished by thermogravimetric analyses, Fourier transform infrared (FTIR) absorption spectra, X-ray diffraction (XRD) and by analysis of nitrogen adsorption/desorption isotherms. In vitro bioactivity can also be assessed by the cytotoxic effect of the glasses on the NIH-3T3 cell line, and by characterization of MC-3T3-E1 cell attachment.

  18. Biomimetic component coating on 3D scaffolds using high bioactivity of mesoporous bioactive ceramics

    Directory of Open Access Journals (Sweden)

    Yun HS

    2011-10-01

    Full Text Available Hui-suk Yun1, Sang-Hyun Kim2, Dongwoo Khang3, Jungil Choi4, Hui-hoon Kim2, Minji Kang31Functional Materials Division, Korea Institute of Materials Science, Gyeongnam, Korea; 2Department of Pharmacology, School of Medicine, Kyungpook National University, Jung-Gu, Daegu, Korea; 3School of Nano and Advanced Materials Science and Engineering and Center for NMBE, Gyeongsang National University, Jinju, Korea; 4Department of Anatomy, Institute of Health Science and School of Medicine, Gyeongsang National University, Jinju, Gyeongnam, KoreaBackground: Mesoporous bioactive glasses (MBGs are very attractive materials for use in bone tissue regeneration because of their extraordinarily high bone-forming bioactivity in vitro. That is, MBGs may induce the rapid formation of hydroxy apatite (HA in simulated body fluid (SBF, which is a major inorganic component of bone extracellular matrix (ECM and comes with both good osteoconductivity and high affinity to adsorb proteins. Meanwhile, the high bioactivity of MBGs may lead to an abrupt initial local pH variation during the initial Ca ion-leaching from MBGs at the initial transplant stage, which may induce unexpected negative effects on using them in in vivo application. In this study we suggest a new way of using MBGs in bone tissue regeneration that can improve the strength and make up for the weakness of MBGs. We applied the outstanding bone-forming bioactivity of MBG to coat the main ECM components HA and collagen on the MBG-polycarplolactone (PCL composite scaffolds for improving their function as bone scaffolds in tissue regeneration. This precoating process can also expect to reduce initial local pH variation of MBGs.Methods and materials: The MBG-PCL scaffolds were immersed in the mixed solution of the collagen and SBF at 37°C for 24 hours. The coating of ECM components on the MBG-PCL scaffolds and the effect of ECM coating on in vitro cell behaviors were confirmed.Results: The ECM components were fully

  19. Bioactivity of Minor Milk Components

    DEFF Research Database (Denmark)

    Nguyen, Duc Ninh

    particular, 3-15% of very low birth weight preterm infants suffer from the most servere form of intestinal inflammation, known as necrotizing enterocolitis (NEC). This disease is incurable with a high mortality rate of 15-30%. Mother’s breast milk consists of different bioactive constituents, and is...... infant formula. Thereafter, bioactive milk components which were preserved in gently-processed infant formula were selected for further investigation of their immunomodulatory activity in cell and preterm pig models. We hope this project will contribute to the research on the development of new...

  20. Bioactive saponins from Dioscorea futschauensis.

    Science.gov (United States)

    Liu, H W; Hu, K; Zhao, Q C; Cui, C B; Kobayashi, H; Yao, X S

    2002-08-01

    A new anti-neoplastic spirostanol saponin, (25S)-spirost-5-en-3 beta, 27-diol-3O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranoside and three known compounds viz. prosapogenin A of dioscin, dioscin and gracilin were isolated from Dioscorea futschauensis by bioactivity-guided fractionation. Their structures were elucidated mainly by means of spectroscopic analysis. Their bioactivity against Pyricularia oryzae and cytotoxic activity on ts-FT210 cell line was evaluated. PMID:12227201

  1. Experimental Study on LTCC Glass-Ceramic Based Dual Segment Cylindrical Dielectric Resonator Antenna

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Gangwar

    2013-01-01

    Full Text Available The measured characteristics in C/X bands, including material properties of a dual segment cylindrical dielectric resonator antenna (CDRA fabricated from glass-ceramic material based on B2O3–La2O3–MgO glass and La(Mg0.5Ti0.5O3 ceramic, are reported. The sintering characteristic of the ceramic in presence of glass is determined from contact angle measurement and DTA. The return loss and input impedance versus frequency characteristics and radiation patterns of CDRA at its resonant frequency of 6.31 GHz are studied. The measured results for resonant frequency and return loss bandwidth of the CDRA are also compared with corresponding theoretical ones.

  2. Bioactive Polymeric Composites for Tooth Mineral Regeneration: Physicochemical and Cellular Aspects

    OpenAIRE

    Joseph M. Antonucci; Drago Skrtic

    2011-01-01

    Our studies of amorphous calcium phosphate (ACP)-based dental materials are focused on the design of bioactive, non-degradable, biocompatible, polymeric composites derived from acrylic monomer systems and ACP by photochemical or chemically activated polymerization. Their intended uses include remineralizing bases/liners, orthodontic adhesives and/or endodontic sealers. The bioactivity of these materials originates from the propensity of ACP, once exposed to oral fluids, to release Ca and PO4 ...

  3. Nanocellulose-based composites and bioactive agents for food packaging.

    OpenAIRE

    Khan, Avik; Huq, Tanzina; Khan, Ruhul A.; Riedl, Bernard; Lacroix, Monique

    2014-01-01

    International audience Global environmental concern, regarding the use of petroleum-based packaging materials, is encouraging researchers and industries in the search for packaging materials from natural biopolymers. Bioactive packaging is gaining more and more interest not only due to its environment friendly nature but also due to its potential to improve food quality and safety during packaging. Some of the shortcomings of biopolymers, such as weak mechanical and barrier properties can ...

  4. Bioactive Glass Nanopowder for theTreatment of Oral Bone Defects

    Directory of Open Access Journals (Sweden)

    MH. Fathi

    2007-09-01

    Full Text Available Objective: Osseous defects around dental implants are often seen when implants are placed in areas with inadequate alveolar bone, or around failing implants. Bone regenera-tion in these areas using bone grafts or its substitutes may improve dental implants prog-nosis. The aim of this study was to prepare and characterize the bioactive glass nanopow-der and development of its coating for treatment of oral bone defects.Materials and Methods: Bioactive bioglass coating was made on stainless steel plates by sol-gel technique. The powder shape and size was evaluated by transmission electron mi-cropscopy, and thermal properties studied using differential thermal analysis (DTA. Structural characterization techniques (XRD were used to analyze and study the structure and phase present in the prepared bioactive glass nanopowder. This nanopowder was immersed in the simulated body fluid (SBF solution. Fourier transform infrared spec-troscopy (FTIR was utilized to recognize and confirm the formation of apatite layer on prepared bioactive glass nanopowder.Results: The bioglass powder size was less than 100 nanometers which was necessary for better bioactivity, and preparing a homogeneous coating. The formation of apatite layer confirmed the bioactivity of the bioglass nanopowder. Crack-free and homogeneous bioglass coatings were achieved with no observable defects.Conclusion: It was concluded that the prepared bioactive glass nanopowder could be more effective as a bone replacement material than conventional bioactive glass to pro-mote bone formation in osseous defects. The prepared bioactive glass nanopowder could be more useful for treatment of oral bone defects compare to conventional hydroxyapatite or bioactive glass.

  5. Abrasive wear behaviour of bio-active glass ceramics containing apatite

    Indian Academy of Sciences (India)

    I Sevim; M K Kulekci

    2006-06-01

    In this study, abrasive wear behaviour of bio-active glass ceramic materials produced with two different processes is studied. Hot pressing process and conventional casting and controlled crystallization process were used to produce bio-active ceramics. Fracture toughness of studied material was calculated by fracture toughness equations using experimental hardness results of the bio-active glass ceramic material. Two fracture toughness equations in the literature were used to identify the wear behaviour of studied ceramics. Wear resistance results that identified with both of the equations were similar. The results showed that the abrasive wear resistance of the bio-active glass ceramics produced with hot pressing process was found to be higher than that of the ceramics produced by conventional casting and controlled crystallization process.

  6. An Experimental Study on Mechanical Modeling of Ceramics Based on Microstructure

    Directory of Open Access Journals (Sweden)

    Ya-Nan Zhang

    2015-11-01

    Full Text Available The actual grinding result of ceramics has not been well predicted by the present mechanical models. No allowance is made for direct effects of materials microstructure and almost all the mechanical models were obtained based on crystalline ceramics. In order to improve the mechanical models of ceramics, surface grinding experiments on crystalline ceramics and non-crystalline ceramics were conducted in this research. The normal and tangential grinding forces were measured to calculate single grit force and specific grinding energy. Grinding surfaces were observed. For crystalline alumina ceramics, the predictive modeling of normal force per grit fits well with the experimental result, when the maximum undeformed chip thickness is less than a critical depth, which turns out to be close to the grain size of alumina. Meanwhile, there is a negative correlation between the specific grinding energy and the maximum undeformed chip thickness. With the decreasing maximum undeformed chip thickness, the proportions of ductile removal and transgranular fracture increase. However, the grinding force models are not applicable for non-crystalline ceramic fused silica and the specific grinding energy fluctuates irregularly as a function of maximum undeformed chip thickness seen from the experiment.

  7. Secondary metabolites and bioactivities of Albizia anthelmintica

    Directory of Open Access Journals (Sweden)

    Tahia K Mohamed

    2013-01-01

    Full Text Available Background: Albizia species are rich in phenolics and terpenes in the different plant organs. They are widely used in traditional Chinese medicine. So this study investigated the phytochemical and biological activities of Albizia Anthelmintica. Materials and Methods: Column chromatography has been performed for the isolation of compounds. Bioactivity studies of A. anthelmintica leaves were carried out on aqueous ethanol extract and some pure compounds were tested for their antioxidant activities. Results: Eight compounds have been isolated for the first time from A. anthelmintica. The aqueous ethanol extract of A. anthelmintica showed moderate anti-inflammatory activity and significant for both analgesic and antioxidant activities. Quercetin-3-O-β-D-glucopyranoside, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-(6β-O-galloyl-β-D-glucopyranoside and quercetin-3-O-(6β-O-galloyl-β-D-glucopyranoside exhibited potent antioxidant scavenging activity towards diphenyl-picrylhydrazine.

  8. Chelating Tendencies of Bioactive Aminophosphonates

    OpenAIRE

    Kiss, Tamas; Lázár, István; Kafarski, Pawel

    1994-01-01

    The metal-binding abilities of a wide variety of bioactive aminophosphonates, from the simple aminoethanephosphonic acids to the rather large macrocyclic polyaza derivatives, are discussed with special emphasis on a comparison of the analogous carboxylic acid and phosphonic acid systems. Examples are given of the biological importance of metal ion – aminophosphonate interactions in living systems, and also of their actual and potential applicability in medicine.

  9. Cerâmicas bioativas: estado da arte Bioactive ceramics: state of the arts

    Directory of Open Access Journals (Sweden)

    Ângela Leão Andrade

    2006-02-01

    Full Text Available Bioactive glasses undergo corrosion with leaching of alkaline ions when exposed to body fluids. This results in the spontaneous formation of a layer of hydroxyapatite (HA, the mineral component of natural bone, which in turn can induce bone growth in vivo. This paper describes the different types of bioactive glasses, the characterization methods currently used, and the main factors that influence their bioactivity. Nucleation and crystallization, the main mechanisms involved in the formation of hydroxyapatite, Ca10(PO46(OH2, are discussed as a function of the chemical composition and the reactivity of the surface of the material. Finally, promising applications are considered.

  10. Bioactive peptides in dairy products

    Directory of Open Access Journals (Sweden)

    Donata Marletta

    2010-01-01

    Full Text Available Bioactive peptides are specific protein fragments that have a positive impact on body functions and conditions and may ultimately influence health. Most of the biological activities are encrypted within the primary sequence of the native protein and can be released by enzymatic hydrolysis and proteolysis or by food processing. Milk is a rich source of bioactive peptides which may contribute to regulate the nervous, gastrointestinal and cardiovascular systems as well as the immune system, confirming the added value of dairy products that, in certain cases, can be considered functional foods. The main biological activities of these peptides and their bioavailability in dairy products are reviewed. The natural concentration of these biomolecules is quite low and, to date one of the main goals has been to realize products enriched with bioactive peptides that have beneficial effects on human health and proven safety. Even though several health-enhancing products have already been launched and their integration in the diet could help in the prevention of chronic diseases such as hypertension, cancer and osteoporosis, more clinical trials are required in order to develop a deeper understanding of the activity of biopeptides on the human physiological mechanisms and also to assess the efficacy of their effects in a long term view. New scientific data are also needed to support their commercialisation in compliance with current regulations.

  11. Mechanochemically synthesized kalsilite based bioactive glass-ceramic composite for dental vaneering

    Science.gov (United States)

    Kumar, Pattem Hemanth; Singh, Vinay Kumar; Kumar, Pradeep

    2015-08-01

    Kalsilite glass-ceramic composites have been prepared by a mechanochemical synthesis process for dental veneering application. The aim of the present study is to prepare bioactive kalsilite composite material for application in tissue attachment and sealing of the marginal gap between fixed prosthesis and tooth. Mechanochemical synthesis is used for the preparation of microfine kalsilite glass-ceramic. Low temperature frit and bioglass have been prepared using the traditional quench method. Thermal, microstructural and bioactive properties of the composite material have been examined. The feasibility of the kalsilite to be coated on the base commercial opaque as well as the bioactive behavior of the coated specimen has been confirmed. This study indicates that the prepared kalsilite-based composites show similar structural, morphological and bioactive behavior to that of commercial VITA VMK95 Dentin 1M2.

  12. Hierarchical Structures and Shaped Particles of Bioactive Glass and Its In Vitro Bioactivity

    Directory of Open Access Journals (Sweden)

    U. Boonyang

    2013-01-01

    Full Text Available In this study, bioactive glass particles with controllable structure and porosity were prepared using dual-templating methods. Block copolymers used as one template component produced mesopores in the calcined samples. Polymer colloidal crystals as the other template component yielded either three-dimensionally ordered macroporous (3DOM products or shaped bioactive glass nanoparticles. The in vitro bioactivity of these bioactive glasses was studied by soaking the samples in simulated body fluid (SBF at body temperature (37°C for varying lengths of time and monitoring the formation of bone-like apatite on the surface of the bioactive glass. A considerable bioactivity was found that all of bioactive glass samples have the ability to induce the formation of an apatite layer on its surface when in contact with SBF. The development of bone-like apatite is faster for 3DOM bioactive glasses than for nanoparticles.

  13. Diopside-fluorapatite-wollastonite based bioactive glasses and glass-ceramics

    OpenAIRE

    Kansal, Ishu

    2015-01-01

    Bioactive glasses and glass–ceramics are a class of biomaterials which elicit special response on their surface when in contact with biological fluids, leading to strong bonding to living tissue. This particular trait along with good sintering ability and high mechanical strength make them ideal materials for scaffold fabrication. The work presented in this thesis is directed towards understanding the composition-structure-property relationships in potentially bioactive glasses...

  14. Bioactive compounds of the main milk constituents and their determination

    OpenAIRE

    Malecký, Lukáš

    2012-01-01

    Diet is a blend of nutrients that the body needs to obtain energy and building materials needed for growth and repair of cells, tissues and organs. The nutrients or bioactive subtances are divided into two main groups: basic nutrients (macronutritients) and additional nutrients (micronutritients). Essential nutrients are divided into proteins, fats, carbohydrates and the body needs in large doses. The first part of this work with the available literature focuses on the milk, its general d...

  15. Bioactive components in fish venoms.

    Science.gov (United States)

    Ziegman, Rebekah; Alewood, Paul

    2015-05-01

    Animal venoms are widely recognized excellent resources for the discovery of novel drug leads and physiological tools. Most are comprised of a large number of components, of which the enzymes, small peptides, and proteins are studied for their important bioactivities. However, in spite of there being over 2000 venomous fish species, piscine venoms have been relatively underrepresented in the literature thus far. Most studies have explored whole or partially fractioned venom, revealing broad pharmacology, which includes cardiovascular, neuromuscular, cytotoxic, inflammatory, and nociceptive activities. Several large proteinaceous toxins, such as stonustoxin, verrucotoxin, and Sp-CTx, have been isolated from scorpaenoid fish. These form pores in cell membranes, resulting in cell death and creating a cascade of reactions that result in many, but not all, of the physiological symptoms observed from envenomation. Additionally, Natterins, a novel family of toxins possessing kininogenase activity have been found in toadfish venom. A variety of smaller protein toxins, as well as a small number of peptides, enzymes, and non-proteinaceous molecules have also been isolated from a range of fish venoms, but most remain poorly characterized. Many other bioactive fish venom components remain to be discovered and investigated. These represent an untapped treasure of potentially useful molecules. PMID:25941767

  16. Bioactive Egg Components and Inflammation

    Directory of Open Access Journals (Sweden)

    Catherine J. Andersen

    2015-09-01

    Full Text Available Inflammation is a normal acute response of the immune system to pathogens and tissue injury. However, chronic inflammation is known to play a significant role in the pathophysiology of numerous chronic diseases, such as cardiovascular disease, type 2 diabetes mellitus, and cancer. Thus, the impact of dietary factors on inflammation may provide key insight into mitigating chronic disease risk. Eggs are recognized as a functional food that contain a variety of bioactive compounds that can influence pro- and anti-inflammatory pathways. Interestingly, the effects of egg consumption on inflammation varies across different populations, including those that are classified as healthy, overweight, metabolic syndrome, and type 2 diabetic. The following review will discuss the pro- and anti-inflammatory properties of egg components, with a focus on egg phospholipids, cholesterol, the carotenoids lutein and zeaxanthin, and bioactive proteins. The effects of egg consumption of inflammation across human populations will additionally be presented. Together, these findings have implications for population-specific dietary recommendations and chronic disease risk.

  17. Nanomodified Peek Dental Implants: Bioactive Composites and Surface Modification—A Review

    Directory of Open Access Journals (Sweden)

    Shariq Najeeb

    2015-01-01

    Full Text Available Purpose. The aim of this review is to summarize and evaluate the relevant literature regarding the different ways how polyetheretherketone (PEEK can be modified to overcome its limited bioactivity, and thereby making it suitable as a dental implant material. Study Selection. An electronic literature search was conducted via the PubMed and Google Scholar databases using the keywords “PEEK dental implants,” “nano,” “osseointegration,” “surface treatment,” and “modification.” A total of 16 in vivo and in vitro studies were found suitable to be included in this review. Results. There are many viable methods to increase the bioactivity of PEEK. Most methods focus on increasing the surface roughness, increasing the hydrophilicity and coating osseoconductive materials. Conclusion. There are many ways in which PEEK can be modified at a nanometer level to overcome its limited bioactivity. Melt-blending with bioactive nanoparticles can be used to produce bioactive nanocomposites, while spin-coating, gas plasma etching, electron beam, and plasma-ion immersion implantation can be used to modify the surface of PEEK implants in order to make them more bioactive. However, more animal studies are needed before these implants can be deemed suitable to be used as dental implants.

  18. Enhanced bioactivity of glass ionomer cement by incorporating calcium silicates.

    Science.gov (United States)

    Chen, Song; Cai, Yixiao; Engqvist, Håkan; Xia, Wei

    2016-01-01

    Glass ionomer cements (GIC) are known as a non-bioactive dental cement. During setting the GIC have an acidic pH, driven by the acrylic acid component. It is a challenge to make GIC alkaline without disturbing its mechanical properties. One strategy was to add slowly reacting systems with an alkaline pH. The aim of the present study is to investigate the possibility of forming a bioactive dental material based on the combination of glass ionomer cement and calcium silicates. Two types of GIC were used as control. Wollastonite (CS also denoted β-CaSiO3) or Mineral Trioxide Aggregate (MTA) was incorporated into the 2 types of GIC. The material formulations' setting time, compressive strength, pH and bioactivity were compared between modified GIC and GIC control. Apatite crystals were found on the surfaces of the modified cements but not on the control GIC. The compressive strength of the cement remained with the addition of 20% calcium silicate or 20% MTA after one day immersion. In addition, the compressive strength of GIC modified with 20% MTA had been increased during the 14 d immersion (p < 0 .05). PMID:26787304

  19. Sol-gel coatings for protection and bioactivation of metals used in orthopaedic devices

    OpenAIRE

    Durán, A; Conde, A. (Ana); Gómez Coedo, Aurora; Dorado, Teresa,; Garcia, C.; Ceré, S.

    2004-01-01

    The aim of this work is the production and characterisation of sol-gel coatings for protection and bioactivation of metals used as standard surgical implant materials, such as stainless steel 316 L (ASTM F138), Co based alloys (ASTM F75) and titanium alloy Ti-6A1-4V (ASTM F67). These films should both prevent degradation of the substrates by wear or corrosion, and bioactivate the material for inducing the formation of a hydroxyapatite (HA) rich layer onto the material surface, thereby permitt...

  20. In vitro bioactivity of a tricalcium silicate cement

    International Nuclear Information System (INIS)

    Tricalcium silicate is the major constituent of Portland cement and the responsible for their mechanical strength at early stages. In order to be used as and additive of conventional calcium phosphate cement (CPC), in vitro bioactivity of a calcium silicate cement (CSC) after soaking in simulated body fluid (SBF) for 14 days was study. The cement was obtained by mixing Ca3SiO5, obtained by sol-gel process, and a Na2HPO4 solution. The morphological and structural changes of the material before and after soaking were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed the formation of a layer of a Hydroxyapatite (HA) onto the CSC cement after soaking for 1h in SBF that became denser with the increase of soaking time. The study suggests that Ca3SiO5 would be an effective additive to improve the bioactivity and long term strength of conventional CPC. (author)

  1. Immobilization of bioactive plasmin reduces the thrombogenicity of metal surfaces.

    Science.gov (United States)

    Wise, Steven G; Michael, Praveesuda L; Waterhouse, Anna; Santos, Miguel; Filipe, Elysse; Hung, Juichien; Kondyurin, Alexey; Bilek, Marcela M M; Ng, Martin K C

    2015-12-01

    Components of many vascular prostheses including endovascular stents, heart valves and ventricular assist devices are made using metal alloys. In these blood contacting applications, metallic devices promote blood clotting, which is managed clinically by profound platelet suppression and/or anticoagulation. Here it is proposed that the localized immobilization of bioactive plasmin, a critical mediator of blood clot stability, may attenuate metallic prosthesis-induced thrombus formation. Previously described approaches to covalently immobilize biomolecules on implantable materials have relied on complex chemical linker chemistry, increasing the possibility of toxic side effects and reducing bioactivity. We utilize a plasma deposited thin film platform to covalently immobilize biologically active plasmin on stainless steel substrates, including stents. A range of in vitro whole blood assays demonstrate striking reductions in thrombus formation. This approach has profound potential to improve the efficacy of a wide range of metallic vascular implants. PMID:26551872

  2. Essential oils: extraction, bioactivities, and their uses for food preservation.

    Science.gov (United States)

    Tongnuanchan, Phakawat; Benjakul, Soottawat

    2014-07-01

    Essential oils are concentrated liquids of complex mixtures of volatile compounds and can be extracted from several plant organs. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties. In addition, some essential oils have been used as medicine. Furthermore, the uses of essential oils have received increasing attention as the natural additives for the shelf-life extension of food products, due to the risk in using synthetic preservatives. Essential oils can be incorporated into packaging, in which they can provide multifunctions termed "active or smart packaging." Those essential oils are able to modify the matrix of packaging materials, thereby rendering the improved properties. This review covers up-to-date literatures on essential oils including sources, chemical composition, extraction methods, bioactivities, and their applications, particularly with the emphasis on preservation and the shelf-life extension of food products. PMID:24888440

  3. Mechanochemical Treatment, Structural Peculiarities, Properties, and Reactivity of SHS Systems Based on Natural Materials. 4. Production of SHS Ceramics Based on Mechanoactivated Materials

    Science.gov (United States)

    Mansurov, Z. A.; Mofa, N. N.; Sadykov, B. S.; Sabaev, Zh. Zh.; Bakkara, A. E.

    2016-01-01

    The present paper considers the influence of mechanochemical treatment of minerals (quartz SiO2, calcite CaCO3, and wollastonite CaSiO3) used as components of the charge mixture for SH synthesis of ceramics with a high level of strength and thermal properties. A positive effect of using various modifiers in mechanochemical treatment of minerals activating the combustion process has been established. Suitable selection of modifiers provides an increase in the strength of synthesized SHS composites due to the formation in the synthesis products of wollastonite, helenite, anorthite, and aluminum nitride, and the decrease in the heat conductivity is due to the formation of an ultraporous structure of specimens. It has been shown that by varying the composition of the charge from the used natural minerals and the conditions of their mechanochemical treatment with modifiers, as well as the sizes of the synthesized specimen in the SHS regime, an object with high strength and thermal properties can be obtained.

  4. Optimization of the extraction process for the seven bioactive compounds in Yukmijihwang-tang, an herbal formula, using response surface methodology

    OpenAIRE

    Jung-Hoon Kim; Hyeun-Kyoo Shin; Chang-Seob Seo

    2014-01-01

    Background: Yukmijihwang-tang (YJT) contains multiple bioactive compounds. Heat-reflux extraction was employed and optimized for the extraction of the bioactive compounds in YJT. Objective: The determination of optimal conditions with maximum yields of bioactive compounds, gallic acid, 5-hydroxymethylfurfural, morroniside, loganin, paeoniflorin, benzoic acid and paeonol, in YJT. Materials and Methods: The extraction ratio (ratio of water to herbal formula), extraction time and extraction numb...

  5. Bioactive furanonaphthoquinones from Crescentia cujete.

    Science.gov (United States)

    Hetzel, C E; Gunatilaka, A A; Glass, T E; Kingston, D G; Hoffmann, G; Johnson, R K

    1993-09-01

    Bioassay-directed fractionation of the MeCOEt extract of Crescentia cujete (Bignonaceae) resulted in the isolation of (2S,3S)-3-hydroxy-5,6-dimethoxydehydroiso-alpha-lapachone [1], (2R)-5,6-dimethoxydehydroiso-alpha-lapachone [2], (2R)-5-methoxydehydroiso-alpha-lapachone [3], 2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione [4], 5-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione [5], 2-isopropenylnaphtho[2,3-b]furan-4,9-dione [6], and 5-hydroxydehydroiso-alpha-lapachone [7]. Compounds 1-3 are new, and all compounds are bioactive, showing selective activity towards DNA-repair-deficient yeast mutants. The isolation, structure elucidation, and biological activities of these compounds are reported. PMID:8254347

  6. Planctomycetes as Novel Source of Bioactive Molecules

    Science.gov (United States)

    Graça, Ana P.; Calisto, Rita; Lage, Olga M.

    2016-01-01

    Marine environments are a fruitful source of bioactive compounds some of which are the newest leading drugs in medicinal therapeutics. Of particular importance are organisms like sponges and macroalgae and their associated microbiome. Planctomycetes, abundant in macroalgae biofilms, are promising producers of bioactive compounds since they share characteristics, like large genomes and complex life cycles, with the most bioactive bacteria, the Actinobacteria. Furthermore, genome mining revealed the presence of secondary metabolite pathway genes or clusters in 13 analyzed Planctomycetes genomes. In order to assess the antimicrobial production of a large and diverse collection of Planctomycetes isolated from macroalgae from the Portuguese coast, molecular, and bioactivity assays were performed in 40 bacteria from several taxa. Two genes commonly associated with the production of bioactive compounds, nonribosomal peptide synthetases (NRPS), and polyketide synthases (PKS) genes were screened. Molecular analysis revealed that 95% of the planctomycetes potentially have one or both secondary bioactive genes; 85% amplified with PKS-I primers and 55% with NRPS primers. Some of the amplified genes were confirmed to be involved in secondary metabolite pathways. Using bioinformatic tools their biosynthetic pathways were predicted. The secondary metabolite genomic potential of strains LF1, UC8, and FC18 was assessed using in silico analysis of their genomes. Aqueous and organic extracts of the Planctomycetes were evaluated for their antimicrobial activity against an environmental Escherichia coli, E. coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, and a clinical isolate of Candida albicans. The screening assays showed a high number of planctomycetes with bioactive extracts revealing antifungal (43%) and antibacterial (54%) activity against C. albicans and B. subtilis, respectively. Bioactivity was observed in

  7. Investigating in vitro bioactivity and magnetic properties of the ferrimagnetic bioactive glass–ceramic fabricated using soda-lime–silica waste glass

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, M. [Department of Materials Science and Engineering, School of Engineering, Shiraz University, Zand Street, Shiraz (Iran, Islamic Republic of); Hashemi, B., E-mail: hashemib@shirazu.ac.ir [Department of Materials Science and Engineering, School of Engineering, Shiraz University, Zand Street, Shiraz (Iran, Islamic Republic of); Shokrollahi, H. [Electroceramics Group, Materials Science and Engineering Department, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of)

    2014-04-01

    The main purpose of the current research is the production and characterization of a ferrimagnetic bioactive glass–ceramic prepared through the solid-state reaction method using soda-lime–silica waste glass as the main raw material. In comparison with the conventional route, that is, the melt-quenching and subsequent heat treatment, the present work is an economical technique. Structural, thermal and magnetic properties of the samples were examined by X-ray diffraction (XRD), differential thermal analysis (DTA) and vibrating sample magnetometer (VSM). The in vitro test was utilized to assess the bioactivity level of the samples by Hanks' solution as simulated body fluid (SBF). The apatite surface layer formation was examined by the scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The calcium ion concentration in the solutions was measured by atomic absorption spectroscopy (AAS). VSM results revealed that with the addition of 5–20 wt% strontium hexaferrite to bioactive glass–ceramics, the ferrimagnetic bioactive glass–ceramics with hysteresis losses between 7024 and 75,852 erg/g were obtained. The in vitro test showed that the onset formation time of hydroxyapatite layer on the surface of the samples was 14 days and after 30 days, this layer was completed. - Highlights: • A novel ferrimagnetic bioactive glass–ceramic was synthesized by an incorporation method. • The bioactive part was synthesized by the solid-state reaction method using soda-lime–silica waste glass. • The doping of SrFe{sub 12}O{sub 19} to Bioglass{sup ®} 45S5 glass–ceramic is likely to decrease bioactivity.

  8. Investigating in vitro bioactivity and magnetic properties of the ferrimagnetic bioactive glass–ceramic fabricated using soda-lime–silica waste glass

    International Nuclear Information System (INIS)

    The main purpose of the current research is the production and characterization of a ferrimagnetic bioactive glass–ceramic prepared through the solid-state reaction method using soda-lime–silica waste glass as the main raw material. In comparison with the conventional route, that is, the melt-quenching and subsequent heat treatment, the present work is an economical technique. Structural, thermal and magnetic properties of the samples were examined by X-ray diffraction (XRD), differential thermal analysis (DTA) and vibrating sample magnetometer (VSM). The in vitro test was utilized to assess the bioactivity level of the samples by Hanks' solution as simulated body fluid (SBF). The apatite surface layer formation was examined by the scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The calcium ion concentration in the solutions was measured by atomic absorption spectroscopy (AAS). VSM results revealed that with the addition of 5–20 wt% strontium hexaferrite to bioactive glass–ceramics, the ferrimagnetic bioactive glass–ceramics with hysteresis losses between 7024 and 75,852 erg/g were obtained. The in vitro test showed that the onset formation time of hydroxyapatite layer on the surface of the samples was 14 days and after 30 days, this layer was completed. - Highlights: • A novel ferrimagnetic bioactive glass–ceramic was synthesized by an incorporation method. • The bioactive part was synthesized by the solid-state reaction method using soda-lime–silica waste glass. • The doping of SrFe12O19 to Bioglass® 45S5 glass–ceramic is likely to decrease bioactivity

  9. Bioactivities and Health Benefits of Wild Fruits.

    Science.gov (United States)

    Li, Ya; Zhang, Jiao-Jiao; Xu, Dong-Ping; Zhou, Tong; Zhou, Yue; Li, Sha; Li, Hua-Bin

    2016-01-01

    Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits. PMID:27527154

  10. Bioactivities and Health Benefits of Wild Fruits

    Directory of Open Access Journals (Sweden)

    Ya Li

    2016-08-01

    Full Text Available Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits.

  11. Comparison of Calcium Hydroxide and Bioactive Glass after Direct Pulp Capping in Primary Teeth

    Directory of Open Access Journals (Sweden)

    R. Haghgoo

    2007-12-01

    Full Text Available Objective: Bioactive glass is often used as a filler material for repair of dental bone defects.In different studies osteogenic potential of this material was proved, but its dentinogenesisproperty is in doubt. The purpose of this study was to evaluate the histological pulp responses of Calcium hydroxide and Bioactive glass placed directly on exposed pulp tissues.Materials and Methods: Twenty teeth to be extracted due to orthodontic reasons were selected. These teeth were divided into two groups and treated with direct pulp capping.Calcium hydroxide was used for 10 teeth and Bioactive glass for 10 teeth. After 60 daysthe teeth were extracted and prepared for histological evaluation. Finally the data was analyzed with exact Fisher test.Results: All teeth treated with Calcium hydroxide showed inflammation. Internal resorption was seen in six teeth, abscess in five teeth and dentinal bridge in two teeth. Inflammationwas seen in three Bioactive glass samples and dentinal bridge in seven teeth, but internal resorption and abscess were not seen.Conclusion: Bioactive glass appears to be superior to Calcium hydroxide as a pulp capping agent in primary teeth.

  12. Development of highly-filled, bioactive acrylic-based composite bone cements for orthopedic and craniofacial surgery: Tuning of material properties after incorporation of calcium phosphate and antimicrobial fillers

    Science.gov (United States)

    Rodriguez, Lucas Carlos

    Bone cements are used in a variety of healthcare specialties ranging from orthopedics to dentistry to craniofacial surgery to spinal disc reconstruction. These materials need characteristics which mimic their surrounding tissues. Currently available materials have struggled to maintain these necessary characteristics. Poly (methyl methacrylate) is a very high strength bio-inert polymer which has been utilized in healthcare since the 1940's. Calcium phosphate cements are well established as being bone mimicking, but cannot sustain the compressive loads in a weight bearing application. This study sought to solve the problem of currently available bone cements by filling calcium phosphates and antimicrobials into an acrylic polymer matrix. The intended outcome was a material capable of retaining high mechanical stability from the acrylic polymer phase, while becoming sufficiently bone mimicking and antimicrobial. This thesis work presented, characterizes the material properties of the developed materials and eventually isolates a material of interest for future studies.

  13. Milk proteins as precursors of bioactive peptides

    OpenAIRE

    Marta Dziuba; Bartłomiej Dziuba; Anna Iwaniak

    2009-01-01

    Milk proteins, a source of bioactive peptides, are the subject of numerous research studies aiming to, among others, evaluate their properties as precursors of biologically active peptides. Physiologically active peptides released from their precursors may interact with selected receptors and affect the overall condition and health of humans. By relying on the BIOPEP database of proteins and bioactive peptides, developed by the Department of Food Biochemistry at the University of Warmia and M...

  14. Pyrazoloquinazolines: Synthetic strategies and bioactivities.

    Science.gov (United States)

    Garg, Mansi; Chauhan, Monika; Singh, Pankaj Kumar; Alex, Jimi Marin; Kumar, Raj

    2015-06-01

    Numerous N-heterocycles are indisputably evidenced to exhibit myriad biological activities. In the recent past, attempts made to condense the various heterocycles have resulted in derivatives possessing better bioactivities. Among many such condensed heterocycles, pyrazoloquinazolines have managed to hold the attention of many researchers, owing to the broad spectrum of activities they portray. This review is the first of its kind to congregate the various pyrazoloquinazolines reported until now and categorizes these structurally isomeric classes into eleven different groups based on the fusion pattern of the ring such as [1,5-c], [5,1-b], [4,3-h], etc. Furthermore, this review is a concerted effort to highlight design, synthetic strategies as well as biological activities of each class of this condensed heterocycle. Structure-activity relationship studies and in silico approaches wherever reported have also been discussed. In addition, manuscript also offers scope for design, synthesis and generation of libraries of unreported classes of pyrazoloquinazolines for the biological evaluation. PMID:25438709

  15. Effect of Bioactive Glass air Abrasion on Shear Bond Strength of Two Adhesive Resins to Decalcified Enamel

    OpenAIRE

    Alireza Eshghi; Maryam Khoroushi; Alireza Rezvani

    2014-01-01

    Objective: Bioactive glass air abrasion is a conservative technique to remove initial decalcified tissue and caries. This study examined the shear bond strength of composite resin to sound and decalcified enamel air-abraded by bioactive glass (BAG) or alumina using etch-and-rinse and self-etch adhesives. Materials and Methods: Forty-eight permanent molars were root-amputated and sectioned mesiodistally. The obtained 96 specimens were mounted in acrylic resin; the buccal and lingual surfaces r...

  16. Bioactive polymers for cardiac tissue engineering

    Science.gov (United States)

    Wall, Samuel Thomas

    2007-05-01

    stabilized injured ventricles, reducing functional loss over 6 weeks, and promoted the survival of transplanted stem cells. In addition, modifications to the hydrogel to impart novel bioactivity through a developed tethered form of the protein sonic hedgehog were synthesized and characterized. This tethered form increased protein potency, induced angiogenesis, and could be incorporated into the hydrogel material for future implantation studies in the injured ventricle.

  17. Bioactive molecules from sea hares.

    Science.gov (United States)

    Kamiya, H; Sakai, R; Jimbo, M

    2006-01-01

    Sea hares, belonging to the order Opisthobranchia, subclass Gastropoda, are mollusks that have attracted many researchers who are interested in the chemical defense mechanisms of these soft and "shell-less" snails. Numbers of small molecules of dietary origin have been isolated from sea hares and some have ecologically relevant activities, such as fish deterrent activity or toxicity. Recently, however, greater attention has been paid to biomedically interesting sea hare isolates such as dolastatins, a series of antitumor peptide/macrolides isolated from Dolabella auricularia. Another series of bioactive peptide/macrolides, as represented by aplyronines, have been isolated from sea hares in Japanese waters. Although earlier studies indicated the potent antitumor activity of aplyronines, their clinical development has never been conducted because of the minute amount of compound available from the natural source. Recent synthetic studies, however, have made it possible to prepare these compounds and analogs for a structure-activity relationship study, and started to uncover their unique action mechanism towards their putative targets, microfilaments. Here, recent findings of small antitumor molecules isolated from Japanese sea hares are reviewed. Sea hares are also known to produce cytotoxic and antimicrobial proteins. In contrast to the small molecules of dietary origin, proteins are the genetic products of sea hares and they are likely to have some primary physiological functions in addition to ecological roles in the sea hare. Based on the biochemical properties and phylogenetic analysis of these proteins, we propose that they belong to one family of molecule, the "Aplysianin A family," although their molecular weights are apparently divided into two groups. Interestingly, the active principles in Aplysia species and Dolabella auricularia were shown to be L-amino acid oxidase (LAAO), a flavin enzyme that oxidizes an alpha-amino group of the substrate with

  18. In vitro study of nano-sized zinc doped bioactive glass

    International Nuclear Information System (INIS)

    Surface reactivity in physiological fluid has been linked to bioactivity of a material. Past research has shown that bioactive glass containing zinc has the potential in bone regeneration field due to its enhanced bioactivity. However, results from literature are always contradictory. Therefore, in this study, surface reactivity of bioactive glass containing zinc was evaluated through the study of morphology and composition of apatite layer formed after immersion in simulated body fluid (SBF). Nano-sized bioactive glass with 5 and 10 mol% zinc were synthesized through quick alkali sol–gel method. The synthesized Zn–bioglass was characterized using field emission scanning electron microscope (FESEM), energy dispersive X-ray spectrometer (EDX), X-ray diffractometer (XRD) and Fourier transform infrared spectrometer (FTIR). Samples after SBF immersion were characterized using scanning electron microscope (SEM) and EDX. Morphological study through SEM showed the formation of spherical apatite particles with Ca/P ratio closer to 1.67 on the surface of 5 mol% Zn–bioglass. Whereas, the 10 mol% Zn–bioglass samples induced the formation of flake-like structure of calcite in addition to the spherical apatite particles with much higher Ca/P ratio. Our results suggest that the higher Zn content increases the bioactivity through the formation of bone-bonding calcite as well as the spherical apatite particles. -- Highlights: ► Nano-sized bioactive glasses were synthesized through quick alkali sol–gel method. ► 5 and 10 mol% Zn–bioglass induced the formation of spherical particles in SBF test. ► 10 mol% Zn–bioglass also induced the formation of flake-like structure. ► The flake-like structure is calcium carbonate; spherical particles are apatite. ► High Zn contents negatively influence the chemical composition of the apatite layer.

  19. Surface bioactivity of plasma implanted silicon and amorphous carbon

    Institute of Scientific and Technical Information of China (English)

    Paul K CHU

    2004-01-01

    Plasma immersion ion implantation and deposition (PⅢ&D) has been shown to be an effective technique to enhance the surface bioactivity of materials. In this paper, recent progress made in our laboratory on plasma surface modification single-crystal silicon and amorphous carbon is reviewed. Silicon is the most important material in the integrated circuit industry but its surface biocompatibility has not been investigated in details. We have recently performed hydrogen PⅢ into silicon and observed the biomimetic growth of apatite on its surface in simulated body fluid. Diamond-like carbon (DLC) is widely used in the industry due to its excellent mechanical properties and chemical inertness. The use of this material in biomedical engineering has also attracted much attention. It has been observed in our laboratory that doping DLC with nitrogen by means of PⅢ can improve the surface blood compatibility. The properties as well as in vitro biological test results will be discussed in this article.

  20. Milk proteins as precursors of bioactive peptides

    Directory of Open Access Journals (Sweden)

    Marta Dziuba

    2009-03-01

    Full Text Available Milk proteins, a source of bioactive peptides, are the subject of numerous research studies aiming to, among others, evaluate their properties as precursors of biologically active peptides. Physiologically active peptides released from their precursors may interact with selected receptors and affect the overall condition and health of humans. By relying on the BIOPEP database of proteins and bioactive peptides, developed by the Department of Food Biochemistry at the University of Warmia and Mazury in Olsztyn (www.uwm.edu.pl/biochemia, the profiles of potential activity of milk proteins were determined and the function of those proteins as bioactive peptide precursors was evaluated based on a quantitative criterion, i.e. the occurrence frequency of bioactive fragments (A. The study revealed that milk proteins are mainly a source of peptides with the following types of activity: antihypertensive (Amax = 0.225, immunomodulating (0.024, smooth muscle contracting (0.011, antioxidative (0.029, dipeptidyl peptidase IV inhibitors (0.148, opioid (0.073, opioid antagonistic (0.053, bonding and transporting metals and metal ions (0.024, antibacterial and antiviral (0.024, and antithrombotic (0.029. The enzymes capable of releasing bioactive peptides from precursor proteins were determined for every type of activity. The results of the experiment indicate that milk proteins such as lactoferrin, α-lactalbumin, β-casein and κ-casein hydrolysed by trypsin can be a relatively abundant source of biologically active peptides.

  1. Fluoride-containing bioactive glasses: Surface reactivity in simulated body fluids solutions

    International Nuclear Information System (INIS)

    Bioactive glasses are used in medical field as bone regenerative materials. They promote the growth of bone tissue surface, and establish interconnections in order to form a continuum with the tissue. The bioactivity of this class of materials, immersed in a real or simulated biological medium, is monitored by the ability to form at its surface a layer of Ca-phosphate, which ought to crystallize in the form of either hydroxy-apatite (H A) or hydroxy-carbonate-apatite (H C A). The present contribution deals with the activity/reactivity of some oxidic materials (to be possibly used as bio-active glasses) that: 1) have been produced through the conventional melt-quench-grin method; 2) belong to the family of Hench's Bio glass (H-glass); 3) have been modified, in respect of H-glass composition by the introduction of variable amounts of Ca-fluoride. In assessing the bioactivity of two families of F-modified glasses, it is herewith shown that the use of some physico-chemical methods, typical of surface chemistry (e.g., surface area determination, IR and Raman vibrational spectroscopic analysis), gives indeed access to what happens at the interface between a complex oxidic material and the surrounding biological medium.

  2. Application of ionic liquid for extraction and separation of bioactive compounds from plants.

    Science.gov (United States)

    Tang, Baokun; Bi, Wentao; Tian, Minglei; Row, Kyung Ho

    2012-09-01

    In recent years, ionic liquids (ILs), as green and designer solvents, have accelerated research in analytical chemistry. This review highlights some of the unique properties of ILs and provides an overview of the preparation and application of IL or IL-based materials to extract bioactive compounds in plants. IL or IL-based materials in conjunction with liquid-liquid extraction (LLE), ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), high performance liquid chromatography (HPLC) and solid-phase extraction (SPE) analytical technologies etc., have been applied successfully to the extraction or separation of bioactive compounds from plants. This paper reviews the available data and references to examine the advantages of IL and IL-based materials in these applications. In addition, the main target compounds reviewed in this paper are bioactive compounds with multiple therapeutic effects and pharmacological activities. Based on the importance of the targets, this paper reviews the applications of ILs, IL-based materials or co-working with analytical technologies. The exploitation of new applications of ILs on the extraction of bioactive compounds from plant samples is expected to increase. PMID:22877739

  3. Optimization of liquid culture conditions of Philippine wild edible mushrooms as potential source of bioactive lipids

    Science.gov (United States)

    With remarkable bioactivities and delightful taste, mushrooms have been a commercial nutraceutical around the world. Mushrooms are cultivated on solid materials. Here we report the successful cultivation of four Philippine edible mushrooms in liquid medium. This work highlights the optimal liquid cu...

  4. The Fabrication and Characterization of PCL/Rice Husk Derived Bioactive Glass-Ceramic Composite Scaffolds

    OpenAIRE

    2014-01-01

    The present study was conducted to fabricate a 3D scaffold using polycaprolactone (PCL) and silicate based bioactive glass-ceramic (R-SBgC). Different concentrations of R-SBgC prepared from rice husk ash (RHA) were combined with PCL to fabricate a composite scaffold using thermally induced phase separation (TIPS) method. The products were then characterized using SEM and EDX. The results demonstrated that R-SBgC in PCL matrix produced a bioactive material which has highly porous structure wit...

  5. Study on surface modification of porous apatite-wollastonite bioactive glass ceramic scaffold

    Science.gov (United States)

    Cao, Bin; Zhou, Dali; Xue, Ming; Li, Guangda; Yang, Weizhong; Long, Qin; Ji, Li

    2008-11-01

    Chitosan (CS) was used to modify the surface of apatite-wollastonite bioactive glass ceramic (AW GC) scaffold to prepare AW/CS composite scaffold. The in vitro bioactivity of the AW/CS composite scaffold was investigated by simulated body fluid (SBF) soaking experiment. Cell growth on the surface of the material was evaluated by co-culturing osteogenic marrow stromal cells (MSCs) of rabbits with the scaffold. The results showed that the compressive strength of AW GC scaffold was improved dramatically after being modified by CS, whereas the mineralization rate was delayed. MSCs can attach well on the surface of the composite scaffold.

  6. Laser sintering of nano 13-93 glass scaffolds: Microstructure, mechanical properties and bioactivity

    Directory of Open Access Journals (Sweden)

    Cao Y.

    2015-01-01

    Full Text Available As the only bioactive material that can bond with both hard tissues and soft tissues, bioactive glass has become much important in the field of tissue engineering. 13-93 bioactive glass scaffolds were fabricated via selective laser sintering (SLS. It was focused on the effects of laser sintering on microstructure and mechanical properties of the scaffolds. The experimental results showed that the sintered layer gradually became dense with the laser power increasing and then some defects occurred, such as macroscopic caves. The optimum compressive strength and fracture toughness were 21.43±0.87 MPa and 1.14±0.09 MPa.m1/2, respectively. In vitro bioactivity showed that there was the bone-like apatite layer on the surface of the scaffolds after soaking in simulated body fluid (SBF, which was further evaluated by Fourier transform infrared spectroscopy (FTIR. Moreover, cell culture study showed MG-63 cells adhered and spread well on the scaffolds, and proliferated with increasing time in cell culture. These indicated excellent bioactivity and biocompatibility of nano 13-93 glass scaffolds.

  7. Effective atomic numbers and electron densities of bioactive glasses for photon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Shantappa, Anil, E-mail: anilmalipatil@yahoo.co.in [Department of Physics, Veerappa Nisty Engineering College, Shorapur-585220, KARNATAKA (India); Hanagodimath, S. M., E-mail: smhmath@rediffmail.com [Department of Physics Gulbarga University, Gulbarga-585106, KARNATAKA (India)

    2015-08-28

    This work was carried out to study the nature of mass attenuation coefficient of bioactive glasses for gamma rays. Bioactive glasses are a group of synthetic silica-based bioactive materials with unique bone bonding properties. In the present study, we have calculated the effective atomic number, electron density for photon interaction of some selected bioactive glasses viz., SiO{sub 2}-Na{sub 2}O, SiO{sub 2}-Na{sub 2}O-CaO and SiO{sub 2}-Na{sub 2}O-P{sub 2}O{sub 5} in the energy range 1 keV to 100 MeV. We have also computed the single valued effective atomic number by using XMuDat program. It is observed that variation in effective atomic number (Z{sub PI,} {sub eff}) depends also upon the weight fractions of selected bioactive glasses and range of atomic numbers of the elements. The results shown here on effective atomic number, electron density will be more useful in the medical dosimetry for the calculation of absorbed dose and dose rate.

  8. Hydrogel/bioactive glass composites for bone regeneration applications: Synthesis and characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Killion, John A., E-mail: jkillion@research.ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Rd, Athlone, Co. Westmeath (Ireland); Kehoe, Sharon, E-mail: sh625116@dal.ca [Department of Applied Oral Sciences, Dalhousie University, Halifax, NS B3H 34R2 (Canada); Geever, Luke M., E-mail: lgeever@ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Rd, Athlone, Co. Westmeath (Ireland); Devine, Declan M., E-mail: ddevine@ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Rd, Athlone, Co. Westmeath (Ireland); Sheehan, Eoin, E-mail: eoinsheehan@aol.com [Department of Trauma and Orthopaedics, MRHT, Tullamore, Co. Offaly (Ireland); Boyd, Daniel, E-mail: d.boyd@dal.ca [Department of Applied Oral Sciences, Dalhousie University, Halifax, NS B3H 34R2 (Canada); Higginbotham, Clement L., E-mail: chigginbotham@ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Rd, Athlone, Co. Westmeath (Ireland)

    2013-10-15

    Due to the deficiencies of current commercially available biological bone grafts, alternative bone graft substitutes have come to the forefront of tissue engineering in recent times. The main challenge for scientists in manufacturing bone graft substitutes is to obtain a scaffold that has sufficient mechanical strength and bioactive properties to promote formation of new tissue. The ability to synthesise hydrogel based composite scaffolds using photopolymerisation has been demonstrated in this study. The prepared hydrogel based composites were characterised using techniques including Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectrometry (EDX), rheological studies and compression testing. In addition, gel fraction, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), porosity and swelling studies of the composites were carried out. It was found that these novel hydrogel bioglass composite formulations did not display the inherent brittleness that is typically associated with bioactive glass based bone graft materials and exhibited enhanced biomechanical properties compared to the polyethylene glycol hydrogel scaffolds along. Together, the combination of enhanced mechanical properties and the deposition of apatite on the surface of these hydrogel based composites make them an ideal candidate as bone graft substitutes in cancellous bone defects or low load bearing applications. Highlights: • Young's modulus increases with the addition of bioactive glasses. • Hydrogel based composites formed an apatite layer in simulated body fluid. • Storage modulus increases with addition of bioactive glasses. • Compressive strength is dependent on molecular weight and bioactive glass loading.

  9. Cholesterol esterase inhibitory activity of bioactives from leaves of Mangifera indica L

    Directory of Open Access Journals (Sweden)

    G M Gururaja

    2015-01-01

    Full Text Available Background: In the earlier studies, methanolic extract of Mangifera indica L leaf was exhibited hypocholesterol activity. However, the bioactive compounds responsible for the same are not reported so far. Objective: To isolate the bioactive compounds with hypocholesterol activity from the leaf extract using cholesterol esterase inhibition assay which can be used for the standardization of extract. Materials and Methods: The leaf methanolic extract of M. indica (Sindoora variety was partitioned with ethyl acetate and chromatographed on silica gel to yield twelve fractions and the activity was monitored by using cholesterol esterase inhibition assay. Active fractions were re-chromatographed to yield individual compounds. Results and Discussion: A major compound mangiferin present in the extract was screened along with other varieties of mango leaves for cholesterol esterase inhibition assay. However, the result indicates that compounds other than mangiferin may be active in the extract. Invitro pancreatic cholesterol esterase inhibition assay was used for bioactivity guided fractionation (BAGF to yield bioactive compound for standardization of extract. Bioactivity guided fractionation afford the active fraction containing 3b-taraxerol with an IC50 value of 0.86μg/ml.Conclusion: This study demonstrates that M.indica methanol extract of leaf have significant hypocholesterol activity which is standardized with 3b-taraxerol, a standardized extract for hypocholesterol activity resulted in development of dietary supplement from leaves of Mangifera indica.

  10. Hydrogel/bioactive glass composites for bone regeneration applications: Synthesis and characterisation

    International Nuclear Information System (INIS)

    Due to the deficiencies of current commercially available biological bone grafts, alternative bone graft substitutes have come to the forefront of tissue engineering in recent times. The main challenge for scientists in manufacturing bone graft substitutes is to obtain a scaffold that has sufficient mechanical strength and bioactive properties to promote formation of new tissue. The ability to synthesise hydrogel based composite scaffolds using photopolymerisation has been demonstrated in this study. The prepared hydrogel based composites were characterised using techniques including Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectrometry (EDX), rheological studies and compression testing. In addition, gel fraction, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), porosity and swelling studies of the composites were carried out. It was found that these novel hydrogel bioglass composite formulations did not display the inherent brittleness that is typically associated with bioactive glass based bone graft materials and exhibited enhanced biomechanical properties compared to the polyethylene glycol hydrogel scaffolds along. Together, the combination of enhanced mechanical properties and the deposition of apatite on the surface of these hydrogel based composites make them an ideal candidate as bone graft substitutes in cancellous bone defects or low load bearing applications. Highlights: • Young's modulus increases with the addition of bioactive glasses. • Hydrogel based composites formed an apatite layer in simulated body fluid. • Storage modulus increases with addition of bioactive glasses. • Compressive strength is dependent on molecular weight and bioactive glass loading

  11. Effective atomic numbers and electron densities of bioactive glasses for photon interaction

    Science.gov (United States)

    Shantappa, Anil; Hanagodimath, S. M.

    2015-08-01

    This work was carried out to study the nature of mass attenuation coefficient of bioactive glasses for gamma rays. Bioactive glasses are a group of synthetic silica-based bioactive materials with unique bone bonding properties. In the present study, we have calculated the effective atomic number, electron density for photon interaction of some selected bioactive glasses viz., SiO2-Na2O, SiO2-Na2O-CaO and SiO2-Na2O-P2O5 in the energy range 1 keV to 100 MeV. We have also computed the single valued effective atomic number by using XMuDat program. It is observed that variation in effective atomic number (ZPI, eff) depends also upon the weight fractions of selected bioactive glasses and range of atomic numbers of the elements. The results shown here on effective atomic number, electron density will be more useful in the medical dosimetry for the calculation of absorbed dose and dose rate.

  12. Tantalum—A bioactive metal for implants

    Science.gov (United States)

    Balla, Vamsi Krishna; Bose, Susmita; Davies, Neal M.; Bandyopadhyay, Amit

    2010-07-01

    Metallic biomaterials currently in use for load-bearing orthopedic applications are mostly bioinert and therefore lack sufficient osseointegration. Although bioactive ceramics such as hydroxyapatite (HA) can spontaneously bond to living bone tissue, low fracture toughness of HA limits their use as a bone substitute for load-bearing applications. Surface modification techniques such as HA coating on metals are current options to improve osseointegration in load-bearing metal implants. Over the last few decades researchers have attempted to find a bioactive metal with high mechanical strength and excellent fatigue resistance that can bond chemically with surrounding bone for orthopedic applications. Recent in vitro, in vivo, and clinical studies demonstrated that tantalum is a promising metal that is bioactive. However, tantalum applications in biomedical devices have been limited by processing challenges rather than biological performances. In this article, we provide an overview of processing aspects and biological properties of tantalum for load-bearing orthopedic applications.

  13. Bioactivity of essential oils: a review on their interaction with food components

    Directory of Open Access Journals (Sweden)

    Antonio eBevilacqua

    2015-02-01

    Full Text Available Essential oils (EOs are liquid preparations, produced from plant materials. Although EOs showed a promising bioactivity in vitro, they could interact in foods with some components (fats, proteins, carbohydrates and pH, thus many authors have reported that a significant effect of EOs towards spoiling and pathogenic microorganisms could be achieved in vivo by using higher amounts of oils. Different methods can be used to assess the bioactivity of EOs (disk diffusion and agar or broth dilution methods; however, there is not a standardised test and researchers propose and use different protocols (evaluating the Minimal Inhibitory Concentration, studying the survival curves, analysis through the scanning electron microscopy, etc..Thereafter, the scope of this review is a focus on interactions of EOs with proteins, carbohydrates, oils, NaCl and pH, as well as a brief description on the different protocols to assess their bioactivity both under in vivo and in vitro conditions.

  14. Development and application of inorganic bioactive ceramic nanocomposites for bone tissue remodeling

    International Nuclear Information System (INIS)

    The objective of the article is to study the synthesis, animal tests and results of clinical applications of the newly proposed kind of bioactive ceramics for full bone tissue restoration-inorganic composites consisting of modified phosphate ceramics, bioactive glasses and bioactive glass-ceramic-so-called SYNTHETBONE materials. Regulation of the composition and structure of the composite can serve to adjust physicochemical and biological properties of the implant with demands of a particular surgery operation and provide the best results of the operations. The presented results demonstrate ample evidence of regulations of resorption rate and mechanism of the composite, favorable biological reaction on its implantation and prove its advantages and high efficiency in numerous surgery operations.

  15. A review of glass-ionomers: From conventional glass-ionomer to bioactive glass-ionomer

    Directory of Open Access Journals (Sweden)

    Maryam Khoroushi

    2013-01-01

    Full Text Available Materials used in the body, especially the materials used in various oral cavity regions should be stable and passive without any interactions with the body tissues or fluids. Dental amalgam, composite resins and dental cements are the materials of choice with such properties. The first attempts to produce active materials, which could interact with the human body tissues and fluids were prompted by the concept that fluoride-releasing materials exert useful effects in the body. The concept of using the "smart" materials in dentistry has attracted a lot of attention in recent years. Conventional glass-ionomer (GI cements have a large number of applications in dentistry. They are biocompatible with the dental pulp to some extent. GI is predominantly used as cements in dentistry; however, they have some disadvantages, the most important of which is lack of adequate strength and toughness. In an attempt to improve the mechanical properties of the conventional GI, resin-modified glass-ionomers have been marketed, with hydrophilic monomers, such as hydroxyethyl methacrylated (HEMA. Some recent studies have evaluated GI with bioactive glass in its structure to validate the claims that such a combination will improve tooth bioactivity, regeneration capacity and restoration. There is ever-increasing interest in the application of bioactive materials in the dental field in an attempt to remineralize affected dentin. The aim of this review article is to evaluate these materials and their characteristics and applications.

  16. Protein co-assembly for the delivery of bioactives.

    OpenAIRE

    Miranda-Tavares, Guilherme; Croguennec, Thomas; Hamon, Pascaline; Peres de sa Peixoto Junior, Paulo; De Carvahlo, Antonio Fernandes; Bouhallab, Said

    2015-01-01

    Introduction Protection and target delivery of food bioactives are main concerns when the manufacture of food products with health-benefit assets is involved. Natural delivery systems for bioactives for instance casein micelle for calcium phosphate are only encountered in some food products and allow the protection and control release of a limited number of bioactives. For this reason, the design of new devices that allow the encapsulation of any types of bioactives is required. Since a large...

  17. Investigation of emulsified, acid and acid-alkali catalyzed mesoporous bioactive glass microspheres for bone regeneration and drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Guohou [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 China (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 China (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 China (China); Chen, Xiaofeng, E-mail: chenxf@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 China (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 China (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 China (China); Dong, Hua [National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 China (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 China (China); School of Biological Science and Engineering, South China University of Technology, Guangzhou 510006 (China); Fang, Liming; Mao, Cong; Li, Yuli; Li, Zhengmao; Hu, Qing [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 China (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 China (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 China (China)

    2013-10-15

    Acid-catalyzed mesoporous bioactive glass microspheres (MBGMs-A) and acid-alkali co-catalyzed mesoporous bioactive glass microspheres (MBGMs-B) were successfully synthesized via combination of sol-gel and water-in-oil (W/O) micro-emulsion methods. The structural, morphological and textural properties of mesoporous bioactive glass microspheres (MBGMs) were characterized by various techniques. Results show that both MBGMs-A and MBGMs-B exhibit regularly spherical shape but with different internal porous structures, i.e., a dense microstructure for MBGMs-A and internally porous structure for MBGMs-B. {sup 29}Si NMR data reveal that MGBMs have low polymerization degree of silica network. The in vitro bioactivity tests indicate that the apatite formation rate of MBGMs-B was faster than that of MBGMs-A after soaking in simulated body fluid (SBF) solution. Furthermore, the two kinds of MBGMs have similar storage capacity of alendronate (AL), and the release behaviors of AL could be controlled due to their unique porous structure. In conclusion, the microspheres are shown to be promising candidates as bone-related drug carriers and filling materials of composite scaffold for bone repair. - Graphical abstract: The morphologies and microstructures of acid-catalyzed mesoporous bioactive glass microspheres (MBGMs-A) and acid-alkali co-catalyzed mesoporous bioactive glass microspheres (MBGMs-B) were observed by scanning electron microscope and transmission electron microscope. MBGMs-A exhibits a dense structure and a porous can be observed in MBGMs-B. The microspheres have a quick inducing-apatite formation ability and show a sustained release of alendronate (AL). Highlights: • A rapid method was reported to prepare mesoporous bioactive glass microspheres. • The addition of ammonia significantly shortens the preparation time. • Acid and acid-alkali co-catalyzed microspheres were studied for the first time. • The materials exhibited excellent in vitro bioactivity and

  18. Investigation of emulsified, acid and acid-alkali catalyzed mesoporous bioactive glass microspheres for bone regeneration and drug delivery

    International Nuclear Information System (INIS)

    Acid-catalyzed mesoporous bioactive glass microspheres (MBGMs-A) and acid-alkali co-catalyzed mesoporous bioactive glass microspheres (MBGMs-B) were successfully synthesized via combination of sol-gel and water-in-oil (W/O) micro-emulsion methods. The structural, morphological and textural properties of mesoporous bioactive glass microspheres (MBGMs) were characterized by various techniques. Results show that both MBGMs-A and MBGMs-B exhibit regularly spherical shape but with different internal porous structures, i.e., a dense microstructure for MBGMs-A and internally porous structure for MBGMs-B. 29Si NMR data reveal that MGBMs have low polymerization degree of silica network. The in vitro bioactivity tests indicate that the apatite formation rate of MBGMs-B was faster than that of MBGMs-A after soaking in simulated body fluid (SBF) solution. Furthermore, the two kinds of MBGMs have similar storage capacity of alendronate (AL), and the release behaviors of AL could be controlled due to their unique porous structure. In conclusion, the microspheres are shown to be promising candidates as bone-related drug carriers and filling materials of composite scaffold for bone repair. - Graphical abstract: The morphologies and microstructures of acid-catalyzed mesoporous bioactive glass microspheres (MBGMs-A) and acid-alkali co-catalyzed mesoporous bioactive glass microspheres (MBGMs-B) were observed by scanning electron microscope and transmission electron microscope. MBGMs-A exhibits a dense structure and a porous can be observed in MBGMs-B. The microspheres have a quick inducing-apatite formation ability and show a sustained release of alendronate (AL). Highlights: • A rapid method was reported to prepare mesoporous bioactive glass microspheres. • The addition of ammonia significantly shortens the preparation time. • Acid and acid-alkali co-catalyzed microspheres were studied for the first time. • The materials exhibited excellent in vitro bioactivity and drug

  19. 可塑型生物活性骨修复材料的制备及性能表征%Preparation, performance and characterization of bioactive bone materials with plasticity

    Institute of Scientific and Technical Information of China (English)

    鹿鸣; 张雪松; 常丽; 崔新爱; 刘朝; 李次会; 李湘杰

    2015-01-01

    BACKGROUND:Foreign injectable sulphate calcium has good biocompatibility, injectability and in situimmobilization, moulding based on adaptation to the shape of bone defects, but the price is expensive. OBJECTIVE:To explore the optimal fabricating parameters of bone repair materials with α-calciumsulfate hemihydrates as the main component, and to study the performance and characterization METHODS:α-Calciumsulfate hemihydrates powder was mixed with sodium hyaluronate at liquid-solid-ratios of 0.2, 0.25, 0.3, 0.35, 0.4 mL/g using vapor-heat method to prepare injectable bone materials. Performance, setting time and compressive strength of the injectable bone was detected. The best liquid-solid-ratio was 0.3 mL/g.α-Calcium sulfate hemihydrates powder was mixed with calcium sulfate dihydrate powder (1%, 2%, 3% mass fractionas) to fabricate injectable bone materials. Performance, setting time and compressive strength of the injectable bone was also detected; meanwhile, the biosafety of the injectable bone was determined. Theinjectable bone material that was made at the liquid-solid-ratio of 0.3 mL/g and by 2% calcium sulfate dihydrate was implanted into Ba-ma swine models of thoracic bone defects. At the time points of 8, 16 and 24 weeks after implantation, histological observation was done. RESULTS AND CONCLUSION: The injectable bone material was made at the liquid-solid-ratio of 0.3 mL/g and by 2% calcium sulfate dihydrate. The initial and final setting time was 4.0-5.0 minutes and 8.0-9.0 minutes, respectively. The compressive strength of the injectable bone reached (8.93±0.23) MPa. These findings indicate that the injectable boen material has good performance, initial setting time and compressive strength meeting the requirements of clinical application and good biosafety. Animal experiments show that the injectable bone can provide space for new bone in creeping substitution way by auto-degradation, with osteogenic activity.%背景:国外研制的可注射性硫

  20. Investigation of bioactivity and cell effects of nano-porous sol–gel derived bioactive glass film

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhijun, E-mail: mokuu@zju.edu.cn [State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640 (China); Ji, Huijiao [College of Life Science, Zhejiang University, Hangzhou, 310028 (China); Hu, Xiaomeng [School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640 (China); Teng, Yu [State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640 (China); Zhao, Guiyun; Mo, Lijuan; Zhao, Xiaoli [College of Life Science, Zhejiang University, Hangzhou, 310028 (China); Chen, Weibo [School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640 (China); Qiu, Jianrong, E-mail: qjr@scut.edu.cn [State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640 (China); Zhang, Ming, E-mail: zhangming201201@126.com [College of Life Science, Zhejiang University, Hangzhou, 310028 (China)

    2013-11-01

    In orthopedic surgery, bioactive glass film coating is extensively studied to improve the synthetic performance of orthopedic implants. A lot of investigations have confirmed that nano-porous structure in bioactive glasses can remarkably improve their bioactivity. Nevertheless, researches on preparation of nano-porous bioactive glasses in the form of film coating and their cell response activities are scarce. Herein, we report the preparation of nano-porous bioactive glass film on commercial glass slide based on a sol–gel technique, together with the evaluation of its in vitro bioactivity through immersion in simulated body fluid and monitoring the precipitation of apatite-like layer. Cell responses of the samples, including attachment, proliferation and osteogenic differentiation, were also investigated using BMSCS (bone marrow derived mesenchymal stem cells) as a model. The results presented here provide some basic information on structural influence of bioactive glass film on the improvement of bioactivity and cellular effects.

  1. Investigating in vitro bioactivity and magnetic properties of the ferrimagnetic bioactive glass-ceramic fabricated using soda-lime-silica waste glass

    Science.gov (United States)

    Abbasi, M.; Hashemi, B.; Shokrollahi, H.

    2014-04-01

    The main purpose of the current research is the production and characterization of a ferrimagnetic bioactive glass-ceramic prepared through the solid-state reaction method using soda-lime-silica waste glass as the main raw material. In comparison with the conventional route, that is, the melt-quenching and subsequent heat treatment, the present work is an economical technique. Structural, thermal and magnetic properties of the samples were examined by X-ray diffraction (XRD), differential thermal analysis (DTA) and vibrating sample magnetometer (VSM). The in vitro test was utilized to assess the bioactivity level of the samples by Hanks' solution as simulated body fluid (SBF). The apatite surface layer formation was examined by the scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The calcium ion concentration in the solutions was measured by atomic absorption spectroscopy (AAS). VSM results revealed that with the addition of 5-20 wt% strontium hexaferrite to bioactive glass-ceramics, the ferrimagnetic bioactive glass-ceramics with hysteresis losses between 7024 and 75,852 erg/g were obtained. The in vitro test showed that the onset formation time of hydroxyapatite layer on the surface of the samples was 14 days and after 30 days, this layer was completed.

  2. Bioactive PMMA bone cement prepared by modification with methacryloxypropyltrimethoxysilane and calcium chloride.

    Science.gov (United States)

    Miyazaki, Toshiki; Ohtsuki, Chikara; Kyomoto, Masayuki; Tanihara, Masao; Mori, Akiko; Kuramoto, Kou-ichi

    2003-12-15

    Bone cement consisting of polymethylmethacrylate (PMMA) powder and methylmethacrylate (MMA) liquid is used extensively for fixation of implants such as artificial hip joints with living bone. This type of cement, however, does not show direct bonding to the living body, and hence the fixation is liable to loosen over a long implantation period. Bioactive materials have received much attention because of their capability for bone-bonding, i.e., bioactivity, when implanted in bony defects. Osteoconduction of the bioactive materials is caused by formation of a bone-like apatite layer through a surface reaction between the material and surrounding body fluid. The apatite formation can be induced by a silanol (Sibond;OH) group formed on the materials as well as a dissolution of calcium ion (Ca(2+)) from the material. Incorporation of alkoxysilane and calcium chloride (CaCl(2)) may provide PMMA bone cement with bioactivity, because alkoxysilane gives Sibond;OH after hydrolysis, whereas CaCl(2) releases Ca(2+). In this study, we investigated the potential on bioactivity of the modified PMMA bone cement with alkoxysilane and calcium chloride. PMMA powder was mixed with various amounts of CaCl(2), and MMA liquid with various amounts of 3-methacryloxypropyltrimethoxysilane (MPS). The mixed paste was immersed in a simulated body fluid (Kokubo solution) that has a similar concentration in inorganic constituents to human blood plasma. After soaking for various periods, apatite formation on the cement was examined. Apatite formation was observed by the addition of CaCl(2) with contents of 16 mass % and more. Incorporation of MPS accelerates the apatite formation. Setting time of the cement was significantly elongated after the addition of MPS, whereas compressive strength significantly decreased with increasing the contents of CaCl(2) and MPS. The hardened cement containing 20 mass % of CaCl(2) in the powder and 20 mass % of MPS in the liquid showed a tendency to be more

  3. Patterning biomaterials for the spatiotemporal delivery of bioactive molecules

    Directory of Open Access Journals (Sweden)

    Silvia eMinardi

    2016-06-01

    Full Text Available The aim of tissue engineering is to promote the repair of functional tissues. For decades, the combined use of biomaterials, growth factors, and stem cells has been at the base of several regeneration strategies. Among these, biomimicry emerged as a robust strategy to efficiently address this clinical challenge. Biomimetic materials, able to recapitulate the composition and architecture of the extracellular matrix, are the materials of choice, for their biocompatibility and higher rate of efficacy. In addition, it has become increasingly clear that restoring the complex biochemical environment of the target tissue is crucial for its regeneration. Towards this aim, the combination of scaffolds and growth factors is required. The advent of nanotechnology significantly impacted the field of tissue engineering by providing new ways to reproduce the complex spatial and temporal biochemical patterns of tissues. This review will present the most recent approaches to finely control the spatiotemporal release of bioactive molecules for various tissue engineering applications.

  4. Patterning Biomaterials for the Spatiotemporal Delivery of Bioactive Molecules.

    Science.gov (United States)

    Minardi, Silvia; Taraballi, Francesca; Pandolfi, Laura; Tasciotti, Ennio

    2016-01-01

    The aim of tissue engineering is to promote the repair of functional tissues. For decades, the combined use of biomaterials, growth factors (GFs), and stem cells has been the base of several regeneration strategies. Among these, biomimicry emerged as a robust strategy to efficiently address this clinical challenge. Biomimetic materials, able to recapitulate the composition and architecture of the extracellular matrix, are the materials of choice, for their biocompatibility and higher rate of efficacy. In addition, it has become increasingly clear that restoring the complex biochemical environment of the target tissue is crucial for its regeneration. Toward this aim, the combination of scaffolds and GFs is required. The advent of nanotechnology significantly impacted the field of tissue engineering by providing new ways to reproduce the complex spatial and temporal biochemical patterns of tissues. This review will present the most recent approaches to finely control the spatiotemporal release of bioactive molecules for various tissue engineering applications. PMID:27313997

  5. Patterning Biomaterials for the Spatiotemporal Delivery of Bioactive Molecules

    Science.gov (United States)

    Minardi, Silvia; Taraballi, Francesca; Pandolfi, Laura; Tasciotti, Ennio

    2016-01-01

    The aim of tissue engineering is to promote the repair of functional tissues. For decades, the combined use of biomaterials, growth factors (GFs), and stem cells has been the base of several regeneration strategies. Among these, biomimicry emerged as a robust strategy to efficiently address this clinical challenge. Biomimetic materials, able to recapitulate the composition and architecture of the extracellular matrix, are the materials of choice, for their biocompatibility and higher rate of efficacy. In addition, it has become increasingly clear that restoring the complex biochemical environment of the target tissue is crucial for its regeneration. Toward this aim, the combination of scaffolds and GFs is required. The advent of nanotechnology significantly impacted the field of tissue engineering by providing new ways to reproduce the complex spatial and temporal biochemical patterns of tissues. This review will present the most recent approaches to finely control the spatiotemporal release of bioactive molecules for various tissue engineering applications. PMID:27313997

  6. Bioactivity of TiN-coated titanium implants

    International Nuclear Information System (INIS)

    Titanium nitride has excellent corrosion and wear resistance properties, and has been used as a hard coating material on titanium hip prostheses. Analysis of explants reveals that calcium phosphate phases grow spontaneously and stick strongly on TiN-coated hip prosthesis heads, indicating a degree of bioactivity of the implant surface which is absent in standard uncoated titanium implants. We investigate the mechanism of TiN oxidation using spectroscopic and first principles molecular dynamics techniques. We find that the deposition of Ca2+ ions - which is the first step of calcium phosphate nucleation - is favoured by TiOxNy oxynitride surface phases. This is due to the presence of mixed-valence states of the surface Ti atoms which leads to localisation of negative charge on surface oxygens, promoting the adsorption of Ca2+ ions. These results indicate that nitridation and controlled oxidation of titanium implant surfaces can promote the in vivo formation of bone-like material

  7. Glutathione conjugation as a bioactivation reaction

    NARCIS (Netherlands)

    Bladeren, P.J. van

    2000-01-01

    In general, glutathione conjugation is regarded as a detoxication reaction. However, depending on the properties of the substrate, bioactivation is also possible. Four types of activation reaction have been recognized: direct-acting compounds, conjugates that are activated through cysteine conjugate

  8. Bioactive Terpenes from Marine-Derived Fungi

    Directory of Open Access Journals (Sweden)

    Ahmed M. Elissawy

    2015-04-01

    Full Text Available Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities.

  9. Marine bioactives and potential application in sports.

    Science.gov (United States)

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D'Orazio, Nicolantonio

    2014-05-01

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. PMID:24796298

  10. Bioactive alkaloids in vertically transmitted fungal endophytes

    Science.gov (United States)

    Plants form mutualistic symbioses with a variety of microorganisms, including endophytic fungi that live inside the plant and cause no symptoms of infection. Some endophytic fungi form defensive mutualisms based on the production of bioactive metabolites that protect the plant from herbivores in exc...

  11. Bromophenols in Marine Algae and Their Bioactivities

    OpenAIRE

    Ming Liu; Poul Erik Hansen; Xiukun Lin

    2011-01-01

    Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect to structure, bioactivities, and their potential application as pharmaceuticals.

  12. Five new bioactive compounds from Chenopodium ambrosioides.

    Science.gov (United States)

    Song, Kun; Zhang, Jian; Zhang, Peng; Wang, Hong-Qing; Liu, Chao; Li, Bao-Ming; Kang, Jie; Chen, Ruo-Yun

    2015-05-01

    Five new bioactive compounds, chenopodiumamines A-D (1-4) and chenopodiumoside A (5), were isolated from the ethanol extract of Chenopodium ambrosioides. The structures of these compounds were elucidated by various spectroscopic means (UV, IR, HR-ESI-MS, 1D and 2D NMR). Compounds 1-3 had moderate antioxidant and anti-inflammatory activities. PMID:26001043

  13. Marine Bioactives and Potential Application in Sports

    Directory of Open Access Journals (Sweden)

    Maria Alessandra Gammone

    2014-04-01

    Full Text Available An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP, such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB, macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports.

  14. Citrus Limonoids: Analysis, Bioactivity, and Biomedical Prospects

    Science.gov (United States)

    This publication is a review of the chemistry, biochemistry and bioactivity of limonoids occurring in citrus. The review chronologically relates the evolution of research in citrus limonoids beginning with their association with bitterness development in citrus juices. The chemical and biochemical...

  15. Bioactive Terpenes from Marine-Derived Fungi

    OpenAIRE

    Ahmed M. Elissawy; Mohamed El-Shazly; Ebada, Sherif S.; AbdelNasser B. Singab; Peter Proksch

    2015-01-01

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities.

  16. Micro PIXE-RBS for the study of Sr release at bioactive glass scaffolds/biological medium interface

    International Nuclear Information System (INIS)

    Strontium is a very interesting element in bone regeneration as it can promote bone formation and limit bone resorption. Bone tissue engineering has a very high potential as a method for bone healing and it requires a 3D macroporous scaffold to serve as a support for cell growth. In that purpose, strontium containing bioactive glass foams made with the sol–gel foaming process are very promising scaffolds as they combine the high bioactivity of bioactive glasses, the beneficial effects of strontium on bone growth and a structure that would allow cell adhesion, cell invasion and vascularization. This paper reports the synthesis of such a material and its in vitro bioactivity study. The release of strontium ions from the material to the biological medium occurs quickly, as shown by ICP-AES results, with the delivery of quantities of Sr ions that should be adequate for bone regeneration. Ion microbeam techniques evidence a very specific behavior of strontium: it is rapidly removed from the inner part of the material but remains in the calcium phosphate layer that is deposited on the surface of the foam pores. It reveals the particular behavior of glass foams compared to other materials suitable for implantation like glass powders of same composition and highlights the interest of ion microbeam techniques in the study of strontium-containing bioactive glass scaffolds

  17. Isolation, identification and application of special bioactive plant components

    International Nuclear Information System (INIS)

    Complete text of publication follows. The wide application of natural and bioactive compounds has became a central issue in the last years. The use of these materials as food additives can be advantageous in several aspects: their natural origin, health protecting properties, possibility for combination of beneficial physiological properties and the recognition and exploitation of synergetic properties can be used in the production of wide range of functional food products. The main objective of the work is - to compare the efficiency of extraction procedures used to obtain different bioactive compounds from different plants, - to identify bioactive components, - to examine the biological activity and bioavailability of the isolated compounds, - to separate and purify the active substances, - to examine the possibility to use these components as functional food additives, - (optimal retrieval, stability, interactions with the food matrix, bio-accessibility). We have examined carrot, purple corn, red cabbage, red pepper, garlic and sea buckthorn extracts. The extraction was carried out with seven different solvents (ethanol: acetic acid:water, acetone, ethanol, n-hexane, ethyl-acetate and hot water). The analysis of the different extraction methods showed that hot water and ethanol were the most efficient solvents, while ethyl-acetate and n-hexane were less effective. The antioxidant activities were determined by FRAP and DPPH methods, antioxidant activities were found to be high in case of garlic and purple corn, while carrot showed lower activity. The components of the extracts were identified by HPLC-MS technique; three unique components were identified in carrot, eleven components in purple corn and nine components in red cabbage. The expected bioavailability and utilization of the components were determined with the application of digestion models: 1 gram of the sample was shaken for 4 hours with 25 ml 0.01 M NaCl solution containing 1 gram pepsin at pH=2.0 in

  18. Fruits Bioactive Compounds Characterization from a New Food Product

    Directory of Open Access Journals (Sweden)

    Valentina Mariana RUS

    2014-12-01

    Full Text Available The aim of this study was (I to create a new product, smart bar type which can be consumed as protective food by adults and children (II to characterize the bioactive compounds from the designed food. The bioactive compounds were identified from nuts, raw seeds of almonds, dry cranberries, dry plums and flax seeds. Secoisolariciresinol (683 ppm has been identified as a major compound in flax seeds.  The vitamin C was quantified by HPLC in a concentration of 35.02 mg% in cranberries extract. The total phenolic content varied from 7.1 mg/g for walnut to 71.8 mg/g for cranberries. In addition, the antioxidative capability of phenolic compounds was monitored and evaluated using a colored free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH. Almond showed better results than walnut in the antioxidant capacity test. The results obtained in this study collect information that enables the use of nuts, raw seeds of almonds, dry cranberries, dry plums and flax seeds as raw material for the production of smart bar which may serve as a new product for food market.

  19. Effects of manufacturing method on surface mineralization of bioactive glasses

    Science.gov (United States)

    Pirayesh, Hamidreza

    Amorphous bioactive glass powders are used as bone-filling materials in many medical applications. Bioactivity is achieved through ion exchange with bodily fluids, leading to surface apatite mineral formation---a necessity for tissue development. Traditional fabrication is by melt-casting and grinding, however sol-gel synthesis is another method which directly produces powders with higher specific surface area and potential for increased ion exchange rates. In this study sol-gel derived powders were manufactured and compared with melt-cast powders to determine the effects of crystallinity, composition, and specific surface area on apatite formation. Powders were immersed in simulated body fluid as a function of time and the evolution of apatite minerals was characterized. Apatite formation was most significantly affected by powder composition, followed by specific surface area; merely having sodium in the powder was more influential than altering the surface area and/or atomic structure, yet high specific surface area was found to enhance reactions on crystalline powders.

  20. Prospects and challenges for industrial production of seaweed bioactives.

    Science.gov (United States)

    Hafting, Jeff T; Craigie, James S; Stengel, Dagmar B; Loureiro, Rafael R; Buschmann, Alejandro H; Yarish, Charles; Edwards, Maeve D; Critchley, Alan T

    2015-10-01

    Large-scale seaweed cultivation has been instrumental in globalizing the seaweed industry since the 1950s. The domestication of seaweed cultivars (begun in the 1940s) ended the reliance on natural cycles of raw material availability for some species, with efforts driven by consumer demands that far exceeded the available supplies. Currently, seaweed cultivation is unrivaled in mariculture with 94% of annual seaweed biomass utilized globally being derived from cultivated sources. In the last decade, research has confirmed seaweeds as rich sources of potentially valuable, health-promoting compounds. Most existing seaweed cultivars and current cultivation techniques have been developed for producing commoditized biomass, and may not necessarily be optimized for the production of valuable bioactive compounds. The future of the seaweed industry will include the development of high value markets for functional foods, cosmeceuticals, nutraceuticals, and pharmaceuticals. Entry into these markets will require a level of standardization, efficacy, and traceability that has not previously been demanded of seaweed products. Both internal concentrations and composition of bioactive compounds can fluctuate seasonally, geographically, bathymetrically, and according to genetic variability even within individual species, especially where life history stages can be important. History shows that successful expansion of seaweed products into new markets requires the cultivation of domesticated seaweed cultivars. Demands of an evolving new industry based upon efficacy and standardization will require the selection of improved cultivars, the domestication of new species, and a refinement of existing cultivation techniques to improve quality control and traceability of products. PMID:26986880

  1. Crystallization of pyroxene phases and physico-chemical properties of glass-ceramics based on Li2O–Cr2O3–SiO2 eutectic glass system

    International Nuclear Information System (INIS)

    The crystallization characteristics, crystalline phase assemblages and solid solution phases developed due to thermally crystallized glasses based on the Li2SiO3–Li2Si2O5–LiCrSi2O6 (1028 ± 3 °C) eutectic glass system by replacing some trivalent oxides instead of Cr2O3 were investigated. The microhardness and chemical durability of the glass-ceramics were also determined. Lithium meta and disilicate (Li2SiO3 and Li2Si2O5), lithium gallium silicate (LiGaSiO4), and varieties of pyroxene phases, including Cr-pyroxene phase, i.e. lithium-kosmochlor (LiCrSi2O6), lithium aluminum silicate (LiAlSi2O6), lithium indium silicate (LiInSi2O6) and pyroxene solid solution of Li-aegerine type [Li (Fe0.5, Cr0.5) Si2O6] were the main crystalline phases formed in the crystallized glasses. There is no evidence for the formation of solid solution or liquid immiscibility gaps between LiAlSi2O6 or LiInSi2O6 phases and LiCrSi2O6 phase. However, LiCrSi2O6 and LiFeSi2O6 components were accommodated in the pyroxene structure under favorable conditions of crystallization to form monomineralic pyroxene solid solution phase of the probably formula [Li (Fe0.5, Cr0.5) Si2O6]. The type and compatibility of the crystallized phases are discussed in relation to the compositional variation of the glasses and heat-treatment applied. The microhardness values of the crystalline materials ranged between 5282 and 6419 MPa while, the results showed that the chemical stability of the glass-ceramics was better in alkaline than in acidic media. - Highlights: • Glass ceramics based on Li2O–Cr2O3–SiO2 eutectic (1028 ± 3 °C) glass were prepared. • LiCrSi2O6 and LiFeSi2O6 phases form monomineralic pyroxene solid solution phase. • Solid solution between LiAlSi2O6 or LiInSi2O6 phases and LiCrSi2O6 phase doesn't form. • Microhardness values of the crystalline materials ranged between 5282 and 6419 MPa. • Chemical stables of the glass-ceramics were better in alkaline than in acidic

  2. Surface modification of biodegradable porous Mg bone scaffold using polycaprolactone/bioactive glass composite.

    Science.gov (United States)

    Yazdimamaghani, Mostafa; Razavi, Mehdi; Vashaee, Daryoosh; Tayebi, Lobat

    2015-04-01

    A reduction in the degradation rate of magnesium (Mg) and its alloys is in high demand to enable these materials to be used in orthopedic applications. For this purpose, in this paper, a biocompatible polymeric layer reinforced with a bioactive ceramic made of polycaprolactone (PCL) and bioactive glass (BG) was applied on the surface of Mg scaffolds using dip-coating technique under low vacuum. The results indicated that the PCL-BG coated Mg scaffolds exhibited noticeably enhanced bioactivity compared to the uncoated scaffold. Moreover, the mechanical integrity of the Mg scaffolds was improved using the PCL-BG coating on the surface. The stable barrier property of the coatings effectively delayed the degradation activity of Mg scaffold substrates. Moreover, the coatings induced the formation of apatite layer on their surface after immersion in the SBF, which can enhance the biological bone in-growth and block the microcracks and pore channels in the coatings, thus prolonging their protective effect. Furthermore, it was shown that a three times increase in the concentration of PCL-BG noticeably improved the characteristics of scaffolds including their degradation resistance and mechanical stability. Since bioactivity, degradation resistance and mechanical integrity of a bone substitute are the key factors for repairing and healing fractured bones, we suggest that PCL-BG is a suitable coating material for surface modification of Mg scaffolds. PMID:25686970

  3. Preparation of porous bioactive ceramic microspheres and in vitro osteoblastic culturing for tissue engineering application.

    Science.gov (United States)

    Hong, S-J; Yu, H-S; Kim, H-W

    2009-06-01

    Microparticulates are useful for directly filling defective tissues as well as for delivering cells and bioactive molecules in regenerative medicine. This paper reports on the production of bioactive ceramic microspheres with an interconnected macropore structure. The sol-gel derived calcium silicate powder was homogenized with an oligomeric Camphene melt, which was used as a novel porogen, and spherical-shaped microparticulates were obtained by an oil-in-water emulsion method. A porous structure was generated through the sublimation of Camphene within the calcium silicate-Camphene solidified blend under ambient conditions. The microspheres retained the crystalline phase of apatite and wollastonite during heat treatment and induced calcium phosphate precipitation under a body-simulating medium, showing the characteristics of bone-bioactive materials. Osteoblastic cells were observed to anchor to and spread well over the surface of the porous microspheres, and further to proliferate actively with culturing time. The bioactive and porous microspheres developed are considered potentially useful in the regeneration of hard tissues as a matrix for tissue engineering as well as a direct filling material. PMID:19141374

  4. The use of A2+B4+O3 additions for production of condensator ferroelectric ceramics based on lead ferroniobate

    International Nuclear Information System (INIS)

    Influence is investigated of A2+B4+O3 additions (BaHfO3, BaZeO3, SrHfO3, SrZrO3 a.oth) on the dielectric properties of ternary lead ferroniobate (LFN) PbFe0.5Nb0.5O3 which is one of the most perspective ferroelectrics for usage as a base of capacitor materials. In the temperature dependences of epsilon of all investigated solid solutions is observed a nondistinct maximum, the temperature of which Tm corresponds to the transition from the ferroelectric phase in the paraelectric one. For LFN ceramics without additions (x=0) Tm=95 deg C and epsilon=27500

  5. Nano/macro porous bioactive glass scaffold

    Science.gov (United States)

    Wang, Shaojie

    Bioactive glass (BG) and ceramics have been widely studied and developed as implants to replace hard tissues of the musculo-skeletal system, such as bones and teeth. Recently, instead of using bulk materials, which usually do not degrade rapidly enough and may remain in the human body for a long time, the idea of bioscaffold for tissue regeneration has generated much interest. An ideal bioscaffold is a porous material that would not only provide a three-dimensional structure for the regeneration of natural tissue, but also degrade gradually and, eventually be replaced by the natural tissue completely. Among various material choices the nano-macro dual porous BG appears as the most promising candidate for bioscaffold applications. Here macropores facilitate tissue growth while nanopores control degradation and enhance cell response. The surface area, which controls the degradation of scaffold can also be tuned by changing the nanopore size. However, fabrication of such 3D structure with desirable nano and macro pores has remained challenging. In this dissertation, sol-gel process combined with spinodal decomposition or polymer sponge replication method has been developed to fabricate the nano-macro porous BG scaffolds. Macropores up to 100microm are created by freezing polymer induced spinodal structure through sol-gel transition, while larger macropores (>200um) of predetermined size are obtained by the polymer sponge replication technique. The size of nanopores, which are inherent to the sol-gel method of glass fabrication, has been tailored using several approaches: Before gel point, small nanopores are generated using acid catalyst that leads to weakly-branched polymer-like network. On the other hand, larger nanopores are created with the base-catalyzed gel with highly-branched cluster-like structure. After the gel point, the nanostructure can be further modified by manipulating the sintering temperature and/or the ammonia concentration used in the solvent

  6. Influence of barium substitution on bioactivity, thermal and physico-mechanical properties of bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Arepalli, Sampath Kumar, E-mail: askumar.rs.cer11@iitbhu.ac.in; Tripathi, Himanshu; Vyas, Vikash Kumar; Jain, Shubham; Suman, Shyam Kumar; Pyare, Ram; Singh, S.P., E-mail: spsinghceram@gmail.com

    2015-04-01

    Barium with low concentration in the glasses acts as a muscle stimulant and is found in human teeth. We have made a primary study by substituting barium in the bioactive glass. The chemical composition containing (46.1 − X) SiO{sub 2−}–24.3 Na{sub 2}O–26.9 CaO–2.6 P{sub 2}O{sub 5}, where X = 0, 0.4, 0.8, 1.2 and 1.6 mol% of BaO was chosen and melted in an electric furnace at 1400 ± 5 °C. The glasses were characterized to determine their use in biomedical applications. The nucleation and crystallization regimes were determined by DTA and the controlled crystallization was carried out by suitable heat treatment. The crystalline phase formed was identified by using XRD technique. Bioactivity of these glasses was assessed by immersion in simulated body fluid (SBF) for various time periods. The formation of hydroxy carbonate apatite (HCA) layer was identified by FTIR spectrometry, scanning electron microscope (SEM) and XRD which showed the presence of HCA as the main phase in all tested bioactive glass samples. Flexural strength and densities of bioactive glasses have been measured and found to increase with increasing the barium content. The human blood compatibility of the samples was evaluated and found to be pertinent. - Highlights: • In vitro bioactivity of soda-lime–baria-phospho-silicate glass was investigated. • HCA formed on surface of glasses was confirmed by XRD, SEM and FTIR spectrometry. • Mechanical properties of glasses were found to increase with barium addition. • Hemolysis showed that 1.2 mol% BaO bioactive glass exhibited better biocompatibility. • Barium substituted bioactive glasses can be used as bone implants.

  7. Influence of barium substitution on bioactivity, thermal and physico-mechanical properties of bioactive glass

    International Nuclear Information System (INIS)

    Barium with low concentration in the glasses acts as a muscle stimulant and is found in human teeth. We have made a primary study by substituting barium in the bioactive glass. The chemical composition containing (46.1 − X) SiO2−–24.3 Na2O–26.9 CaO–2.6 P2O5, where X = 0, 0.4, 0.8, 1.2 and 1.6 mol% of BaO was chosen and melted in an electric furnace at 1400 ± 5 °C. The glasses were characterized to determine their use in biomedical applications. The nucleation and crystallization regimes were determined by DTA and the controlled crystallization was carried out by suitable heat treatment. The crystalline phase formed was identified by using XRD technique. Bioactivity of these glasses was assessed by immersion in simulated body fluid (SBF) for various time periods. The formation of hydroxy carbonate apatite (HCA) layer was identified by FTIR spectrometry, scanning electron microscope (SEM) and XRD which showed the presence of HCA as the main phase in all tested bioactive glass samples. Flexural strength and densities of bioactive glasses have been measured and found to increase with increasing the barium content. The human blood compatibility of the samples was evaluated and found to be pertinent. - Highlights: • In vitro bioactivity of soda-lime–baria-phospho-silicate glass was investigated. • HCA formed on surface of glasses was confirmed by XRD, SEM and FTIR spectrometry. • Mechanical properties of glasses were found to increase with barium addition. • Hemolysis showed that 1.2 mol% BaO bioactive glass exhibited better biocompatibility. • Barium substituted bioactive glasses can be used as bone implants

  8. Bioactive Polymeric Composites for Tooth Mineral Regeneration: Physicochemical and Cellular Aspects

    Directory of Open Access Journals (Sweden)

    Joseph M. Antonucci

    2011-09-01

    Full Text Available Our studies of amorphous calcium phosphate (ACP-based dental materials are focused on the design of bioactive, non-degradable, biocompatible, polymeric composites derived from acrylic monomer systems and ACP by photochemical or chemically activated polymerization. Their intended uses include remineralizing bases/liners, orthodontic adhesives and/or endodontic sealers. The bioactivity of these materials originates from the propensity of ACP, once exposed to oral fluids, to release Ca and PO4 ions (building blocks of tooth and bone mineral in a sustained manner while spontaneously converting to thermodynamically stable apatite. As a result of ACP’s bioactivity, local Ca- and PO4-enriched environments are created with supersaturation conditions favorable for the regeneration of tooth mineral lost to decay or wear. Besides its applicative purpose, our research also seeks to expand the fundamental knowledge base of structure-composition-property relationships existing in these complex systems and identify the mechanisms that govern filler/polymer and composite/tooth interfacial phenomena. In addition to an extensive physicochemical evaluation, we also assess the leachability of the unreacted monomers and in vitro cellular responses to these types of dental materials. The systematic physicochemical and cellular assessments presented in this study typically provide model materials suitable for further animal and/or clinical testing. In addition to their potential dental clinical value, these studies suggest the future development of calcium phosphate-based biomaterials based on composite materials derived from biodegradable polymers and ACP, and designed primarily for general bone tissue regeneration.

  9. Bioactivity of thermal plasma synthesized bovine hydroxyapatite/glass ceramic composites

    International Nuclear Information System (INIS)

    Bone injuries and failures often require the inception of implant biomaterials. Research in this area is receiving increasing attention worldwide. A variety of artificial bone materials, such as metals, polymeric materials, composites and ceramics, are being explored to replace diseased bones. Calcium phosphate ceramics are currently used as biomaterials for many applications in both dentistry and orthopedics. Bioactive silicate-based glasses show a higher bioactive behaviour than calcium phosphate materials. It is very interesting to study the mixtures of HA and silicate-based glasses. In the present study; natural bovine hydroxyapatite / SiO2-CaO-MgO glass composites were produced using the Transferred arc plasma (TAP) melting method. TAP melting route is a brisk process of preparation of glass-ceramics in which the raw materials are melted in the plasma and crystallization of the melt occurs while cooling down at a much faster rate in relatively short processing times compared to the conventional methods of manufacture of glass ceramics/composites. It is well known that; one essential step to the understanding of the biological events occurring at the bone tissue/material interface is the biological investigation by in vitro tests. Cell lines are commonly used for biocompatibility tests, and are very efficient because of their reproducibility and culture facility. In this study, we report the results of a study on the response of primary cultures of human fibroblast cells to TAP melted bioactive glass ceramics.

  10. Bioactivity of mica/apatite glass ceramics

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The bioactivity of mica/apatite glass ceramic composites, including the in vitro behavior in simulated body fluid and the histological appearance of the interface between the mica/apatite glass ceramics and the rabbit mandible defect in vivo under a dynamic condition. The results show that biological apatite layer forms on the surface of the mica/apatite glass ceramics after 1 d of immersion in the simulated body fluid, and becomes dense after 14 d. In vivo tests indicate that bone formation occurs after implantation for 14 d, and strong bonding of bone to the implant occurs after 42 d. No aseptic loosening occurs during 42 d of implantation. The finding shows that mica/apatite glass ceramics have good bioactivity and osteoconductivity for constructing bone graft, and can be promising for biomedical application.

  11. Physiological removal of silicon from bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Lai, W. [Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Bioengineering; Garino, J. [Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Orthopaedic Surgery; Flaitz, C.M. [Texas Univ., Houston, TX (United States). Div. of Oral and Maxillofacial Pathology; Ducheyne, P. [Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Bioengineering; Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Orthopaedic Surgery

    2001-07-01

    Bioactive glass granules were implanted in the paraspinal muscle and tibiae of rabbits in order to determine the pathway of the silicon released from bioactive glass in vivo. We traced and quantified the silicon released by obtaining 24-hour urine samples, as well as blood samples for up to 7 months after implantation. Furthermore, local muscle and bone tissue as well as the following organs were resected for chemical and histopathological analyses: brain, heart, kidney, liver, lung, lymph nodes, spleen, and thymus. The concentrations of silicon found in the urine were well below saturation and no accumulation of silicon was found in the major organs after silicon excretion had halted. The removal of silicon from the body matrix was slower overall compared to an intramuscular site, taking a total of 24 weeks versus 19 weeks to complete silicon removal, respectively. (orig.)

  12. Synthesis of Bioactive Natural Polymethoxyflavones and Their Vinyl Ether Derivatives

    Institute of Scientific and Technical Information of China (English)

    CAI Shuang-lian; LIU Shuang; LIU Li; WANG Qiu-an

    2012-01-01

    Bioactive natural polymethoxyflavones 1-6 and their vinyl ether derivatives 7-15 were synthesized by bromination,aromatic nucleophilic substitution,methylation,benzyl protection,Friedel-Crafts acetylation,aldol condensation,cyclization,DDQ dehydrogenation,regioselective demethylation,debenzylation and O-prenylation or O-farnesylation with resorcinol and appropriate substituted benzaldehydes as starting materials.Among them,compounds 7-15 are new compounds.Natural products 2-4 were firstly total synthesized.The syntheses of compounds 1,5 and 6 were efficiently improved by the new synthetic routes.The structures of all synthetic compounds were confirmed by NMR,IR spectra and MS.

  13. Purification, structure and function of bioactive peptides

    OpenAIRE

    Eriste, Elo

    2004-01-01

    Peptides are vitally important molecules and many evoke cellular responses. The completion of several genome sequencing projects has revealed a number of new genes. However, as functional peptides often contain posttranslational modifications and/or occur at various lengths, it is of great importance to detect, purify and characterize novel bioactive peptides. To achieve these goals, new methods for peptide detection, isolation and functional characterization have to be d...

  14. Bioactive compounds in whole grain wheat

    OpenAIRE

    Mateo Anson, N.

    2010-01-01

    Bread can be healthier! Consuming whole-grain foods can prevent cardiovascular diseases, type-2 diabetes and metabolic syndrome. This is due to bioactive compounds in whole grain, such as antioxidants and anti-inflammatory compounds. We found that the different fractions of a wheat grain vary much in their content. The external fractions of the grain, the bran and specially the aleurone, are the richest. We observed that processing the bran in whole-grain breads increased three times the leve...

  15. Bioactive Compounds from Marine Bacteria and Fungi

    OpenAIRE

    Debbab, Abdessamad; Aly, Amal H.; Lin, Wen H.; Proksch, Peter

    2010-01-01

    Summary Marine bacteria and fungi are of considerable importance as new promising sources of a huge number of biologically active products. Some of these marine species live in a stressful habitat, under cold, lightless and high pressure conditions. Surprisingly, a large number of species with high diversity survive under such conditions and produce fascinating and structurally complex natural products. Up till now, only a small number of microorganisms have been investigated for bioactive me...

  16. NOVEL BIOACTIVE COMPOUNDS FROM MANGROVE DERIVED ACTINOMYCETES

    OpenAIRE

    Kumari Amrita; Jain Nitin; Subathra Devi, C.

    2012-01-01

    Mangrove is most productive and unexplored ecosystem that approximately covers one fourth of world coastline with high diversity of thriving organism. Recently the rate of isolation of novel bioactive compounds from microorganism living in mangrove forest has tremendously increased which is reflected in significant hasten for exploration of mangrove actinomycetes. Actinomycetes are group of bacteria which are extremely interesting as active producers of many primary and secondary metabolites....

  17. Nanochemoprevention by Bioactive Food Components: A Perspective

    OpenAIRE

    Siddiqui, Imtiaz A.; Mukhtar, Hasan

    2010-01-01

    Chemoprevention through the use of bioactive food components is a practical approach for cancer control. Despite abundant efficacy data under preclinical settings, this strategy has resulted in limited success for human cancer control. Amongst many reasons, inefficient systemic delivery and bioavailability of promising chemopreventive agents are considered to significantly contribute to such a disconnect. We recently introduced a novel concept in which we utilized nanotechnology for enhancing...

  18. Nanoencapsulation of bioactive compounds for food applications

    OpenAIRE

    Sessa, Mariarenata

    2012-01-01

    2010 - 2011 The increase in dietary-intake-related illnesses, such as obesity, cardiovascular diseases, hypertension, diabetes and cancer, have made in recent years the development of health-and-wellness promoting foods a priority of the food industry. Clinical studies have demonstrated tangible health benefits that may be derived from the intake of bioactive compounds. However many difficulties are associated with their inclusion in food matrices, due to a very low solubility in water and...

  19. Bioactive Compounds Found in Brazilian Cerrado Fruits

    OpenAIRE

    Elisa Flávia Luiz Cardoso Bailão; Ivano Alessandro Devilla; Edemilson Cardoso da Conceição; Leonardo Luiz Borges

    2015-01-01

    Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provi...

  20. Characterisation by PIXE method of trace elements during physico-chemical reactions at the periphery of bioactive glass pastilles in contact with biological fluids

    OpenAIRE

    Jallot, Edouard; Moretto, P.

    2005-01-01

    The prerequisite for bioactive glasses to bond to living bone is the formation of biologically active apatites on their surface in the body. Reactions and bioactivity mechanisms between bioactive glasses and bone depend on the glass composition. We study a glass in the SiO2-Na2O-CaO-P2O5-K2O-Al2O3-MgO system. To characterise physico-chemical reactions at the materials periphery, we immersed the glass pastilles into biological fluids for delays of 5, 10 and 20 days. The surface changes were st...

  1. Novel bioactive Co-based alloy/FA nanocomposite for dental applications

    Directory of Open Access Journals (Sweden)

    Mohammadhossein Fathi

    2012-01-01

    Full Text Available Background: Dental cobalt base alloys are biocompatible dental materials and have been widely used in dentistry. However, metals are bioinert and may not present bioactivity in human body. Bioactivity is the especial ability to interact with human body and make a bonding to soft and hard tissues. The aim of the present research was fabrication and bioactivity evaluation of novel cobalt alloy/Fluorapatite nanocomposite (CoA/FaNC with different amounts of Fluorapatite (FA nanopowder. Materials and Methods: Co-Cr-Mo alloy (ASTM F75 powder was prepared and mixed in a planetary ball mill with different amounts of FA nanopowders (10, 15, 20% wt. Prepared composite powders were cold pressed and sintered at 1100°C for 4 h. X-ray diffraction (XRD, scanning electron microscopy and transition electron microscopy techniques were used for phase analysis, crystallite size determination of FA and also for phase analysis and evaluation of particle distribution of composites. Bioactivity behavior of prepared nanocomposites was evaluated in simulated body fluid (SBF for 1 up to 28 days. Results: Results showed that nucleus of apatite were formed on the surface of the prepared CoA/FaNC during 1 up to 28 days immersion in the SBF solution. On the other hand, CoA/FaNC unlike Co-base alloy possessed bone-like apatite-formation ability. Conclusion: It was concluded that bioinert Co-Cr-Mo alloy could be successfully converted into bioactive nanocomposite by adding 10, 15, 20 wt% of FA nano particles.

  2. Are bioactive-rich fractions functionally richer?

    Science.gov (United States)

    Imam, Mustapha Umar; Ismail, Maznah; Ooi, Der Jiun; Azmi, Nur Hanisah; Sarega, Nadarajan; Chan, Kim Wei; Bhanger, Muhammad Iqbal

    2016-08-01

    Plant bioresources are relied upon as natural, inexpensive, and sustainable remedies for the management of several chronic diseases worldwide. Plants have historically been consumed for medicinal purposes based on traditional belief, but this trend is currently changing. The growing interest in the medicinal properties of plant bioresources stems from concerns of side effects and other adverse effects caused by synthetic drugs. This interest has yielded a better understanding of the roles of plant bioactive compounds in health promotion and disease prevention, including the underlying mechanisms involved in such functional effects. The desire to maximize the potential of phytochemicals has led to the development of "rich fractions," in which extracts contain bioactive compounds in addition to elevated levels of the primary compound. Although a rich fraction effectively increases the bioactivity of the extract, the standardization and quality assurance process can be challenging. However, the supercritical fluid extraction (SFE) system is a promising green technology in this regard. Future clinical and pharmacological studies are needed to fully elucidate the implications of these preparations in the management of human diseases, thereby fostering a move toward evidence-based medicine. PMID:25641328

  3. Radiation and photografting as complementary techniques for immobilizing bioactive materials

    Science.gov (United States)

    Garnett, J. L.; Jankiewicz, S. V.; Long, M. A.; Sangster, D. F.

    The technique of radiation grafting to immobilize a typical enzyme, trypsin, to three representative backbone polymers namely polypropylene, PVC and polystyrene, is described. The process involves the simultaneous grafting of p-nitrostyrene to the polymer, the nitro group subsequently being converted to its isothiocyanato derivative to which trypsin is attached. For this immobilization work, the utilization of additives which enhance grafting is shown to be an advantage. Typical of the additives used are mineral acids (≈0.1M) and polyfunctional monomers (≈1% v/v), the two acting in a synergistic fashion when used together. A new class of additives, namely metal salts such as LiClO 4, which also increase grafting yields has now been discovered. The reactivity of these salts in grafting enhancement is compared with that of mineral acid. A new model for the modus operandi of metal salts as well as acids in grafting enhancement is proposed whereby increased grafting yields are attributed to increased partitioning of monomer into the graft region in the presence of ionic solutes. The significance of using these additives to prepare radiation copolymers for enzyme immobilization is discussed. In addition to ionizing radiation, UV is also shown to be of value as an initiator for the preparation of graft copolymers for enzyme immobilization, however the presence of sensitizer in the copolymer may limit the photografting method. The possibility of using radiation curing processes involving electron beam (EB) and high powered (300 W/inch) UV sources for immobilization work has been explored and found to be feasible. The curing system possesses great potential for the current immobilization work since complete polymerization is achieved in a fraction of a second.

  4. Radiation and photografting as complementary techniques for immobilizing bioactive materials

    International Nuclear Information System (INIS)

    The technique of radiation grafting to immobilize a typical enzyme, trypsin, to three representative backbone polymers namely polypropylene, PVC and polystyrene, is described. The process involves the simultaneous grafting of p-nitrostyrene to the polymer, the nitro group subsequently being converted to its isothiocyanato derivative to which trypsin is attached. For this immobilization work, the utilization of additives which enhance grafting is shown to be an advantage. Typical of the additives used are mineral acids (approx. 0.1M) and polyfunctional monomers (approx. 1% v/v), the two acting in a synergistic fashion when used together. A new class of additives, namely metal salts such as LiC104, which also increase grafting yields has now been discovered. The reactivity of these salts in grafting enhancement is compared with that of mineral acid. A new model for the modus operandi of metal salts as well as acids in grafting enhancement is proposed whereby increased grafting yields are attributed to increased partitioning of monomer into the graft region in the presence of ionic solutes. The significance of using these additives to prepare radiation copolymers for enzyme immobilization is discussed. In addition to ionizing radiation, UV is also shown to be of value as an initiator for the preparation of graft copolymers for enzyme immobilization, however the presence of sensitizer in the copolymer may limit the photografting method. The possibility of using radiation curing processes involving electron beam (EB) and high powered (300 W/inch) UV sources for immobilization work has been explored and found to be feasible. The curing system possesses great potential for the current immobilization work since complete polymerization is achieved in a fraction of a second. (author)

  5. Functional size analysis of bioactive materials by radiation inactivation

    International Nuclear Information System (INIS)

    When the research on various proteins including enzymes is carried out, first molecular weight is measured. The physical chemical methods used for measuring molecular weight cannot measure it in the state of actually acting in living bodies. Radiation inactivation method is the unique method which can measure the molecular weight of the active substances in living bodies. Paying attention to this point, recently it is attempted to measure the activity unit of enzymes, receptors and others, and to apply to the elucidation of their functions. In this report, the concept of the method of measuring molecular size based on radiation inactivation, the detailed experimental method and the points to which attention must be paid are described. Also its application to the elucidation of living body functions according to the example of the studies by the author is reported. The concept of the measurement of molecular weight by radiation inactivation is based on target theory. The preparation of samples, the effect of oxygen, radiation sources, dosimetry, irradiation temperature, internal standard process and so on are reported. The trend of the research is shown. (K.I.)

  6. Biodegradable mesoporous bioactive glass nanospheres for drug delivery and bone tissue regeneration

    Science.gov (United States)

    Wang, Xiaojian; Li, Wei

    2016-06-01

    Bioactive inorganic materials are attractive for hard tissue regeneration, and they are used as delivery vehicles for pharmaceutical molecules, scaffolds and components for bio-composites. We demonstrated mesoporous bioactive glass (BG) nanospheres that exhibited the capacity to deliver pharmaceutical molecules. Mesoporous BG nanospheres with variable Ca to Si ratios were synthesized using sol–gel chemistry. By controlling the hydrolysis and condensation conditions, the diameter of the mesoporous BG nanospheres was changed from 300 nm to 1500 nm. The porous structure and surface area of the BG nanospheres were shown to be dependent on their composition. The surface area of the BG nanospheres decreased from 400 ± 2 m2 g‑1 to 56 ± 0.1 m2 g‑1 when the Ca/Si ratio increased from 5 to 50 at.%. When the mesoporous BG nanospheres were loaded with ibuprofen (IBU), they exhibited a sustained release profile in simulated body fluid (SBF). In the meantime, the IBU-loaded BG nanospheres degraded in SBF, and induced apatite layer formation on the surface as a result of their good bioactivity. When the BG nanospheres were used as a composite filler to poly (ε-caprolactone) (PCL), they were shown to be effective at improving the in vitro bioactivity of PCL microspheres.

  7. Remineralization efficiency of bioactive glass on artificially induced carious lesion an in-vitro study

    Directory of Open Access Journals (Sweden)

    Sai Sathya Narayana

    2014-01-01

    Full Text Available Objectives: The objective of this study is to investigate the efficacy of bioactive glass containing product on remineralization of artificial induced carious enamel lesion and to compare its efficiency with other remineralization products using an in-vitro pH cycling method. The null hypothesis tested was bioactive glass has no effect on enamel remineralization. Materials and Methods: A total of 20 enamel samples of human molar teeth were subjected to artificial caries lesion formation using pH cycling method and was verified using high resolution scanning electron microscope (HRSEM. Each demineralized sample was then divided into five test groups each containing twenty. Group A - Bioactive glass (SHY-NM, Group B - Fluoride tooth paste (Amflor, Group C - CPP-ACP (Tooth mousse, Group D - CPP-ACPF (Tooth mousse plus, Group E - control. All the test groups were exposed to the pH cycling regime, the remineralizing agents were applied for 10 min except control. After 10 days period, the entire test groups were evaluated with HRSEM and quantitative assessment by energy dispersive X-ray spectroscopy. The obtained data was analyzed statistically using one-way ANOVA, Student′s t-test and Tukey′s multiple comparison tests. P ≤ 0.05 was considered to be significant. Results: Rejection of the null hypothesis and highlights the concept of biomimetic bioactive glass as an effective remineralizing agent. Clinical Relevance: To focus on the importance of minimal invasive treatment on incipient carious lesion by remineralization.

  8. Preparation and biocompatibility of poly (methyl methacrylate reinforced with bioactive particles

    Directory of Open Access Journals (Sweden)

    Pereira Marivalda de Magalhães

    2003-01-01

    Full Text Available Calcium phosphates and bioactive glasses have been used in many biomedical applications for more than 30 years due basically to their bioactive behavior. However, ceramics are too brittle for applications that require high levels of toughness and easy processability. In this work, a biphasic calcium phosphate (BCP and a bioactive glass composition (BG were combined with polymers to produce composites with tailorable properties and processability. The BCP particles were synthesized by a precipitation technique. The BG particles were produced by sol-gel processing. The BCP particles were treated with a silane agent to improve the compatibility between particles and the polymer matrix. Dense samples were produced by hot pressing (200 °C a mixture of 30 wt.% of particles in poly (methyl methacrylate. The samples produced were characterized by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Mechanical properties were evaluated by a three point bending test. Samples were also submitted to in vitro bioactivity test and in vivo toxicity test. Results showed that the production of the composites was successfully achieved, yielding materials with particles well dispersed within the matrices. Evaluation of the in vivo inflammatory response showed low activity levels for all composites although composites with silane treated BCP particles led to milder inflammatory responses than composites with non-treated particles.

  9. Natural Bioactive Compounds from Winery By-Products as Health Promoters: A Review

    Directory of Open Access Journals (Sweden)

    Ana Teixeira

    2014-09-01

    Full Text Available The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L. are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used. Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health.

  10. Natural bioactive compounds from winery by-products as health promoters: a review.

    Science.gov (United States)

    Teixeira, Ana; Baenas, Nieves; Dominguez-Perles, Raul; Barros, Ana; Rosa, Eduardo; Moreno, Diego A; Garcia-Viguera, Cristina

    2014-01-01

    The relevance of food composition for human health has increased consumers' interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health. PMID:25192288

  11. Bioactive extract from moringa oleifera inhibits the pro-inflammatory mediators in lipopolysaccharide stimulated macrophages

    Directory of Open Access Journals (Sweden)

    Masoumeh Tangestani Fard

    2015-01-01

    Full Text Available Introduction: Inflammation is a well-known physiological response to protect the body against infection and restore tissue injury. Nevertheless, the chronic inflammation can trigger various inflammatory associated diseases/disorder. Moringa oleifera is a widely grown plant in most tropical countries and it has been recognized traditionally for several medicinal benefits. Objectives: The objective of this study was to investigate the anti-inflammatory properties of M. oleifera extract on lipopolysaccharide (LPS - stimulated macrophages. Materials and Methods: The anti-inflammatory effect of M. oleifera hydroethanolic bioactive leaves extracts was evaluated by assessing the inhibition of nitric oxide (NO production during Griess reaction and the expression of pro-inflammatory mediators in macrophages. Results: Interestingly, we found that M. oleifera hydroethanolic bioactive leaves extract significantly inhibited the secretion of NO production and other inflammatory markers such as prostaglandin E 2 , tumor necrosis factor alpha, interleukin (IL-6, and IL-1b. Meanwhile, the bioactive extract has induced the production of IL-10 in a dose-dependent manner. In addition, M. oleifera hydroethanolic bioactive leaves extract effectively suppressed the protein expression of inflammatory markers inducible NO synthase, cyclooxygenase-2, and nuclear factor kappa-light-chain-enhancer of activated B-cells p65 in LPS-induced RAW264.7 macrophages in a dose-dependent manner. Conclusion: These findings support the traditional use of M. oleifera plant as an effective treatment for inflammation associated diseases/disorders.

  12. Are lithium niobate (LiNbO{sub 3}) and lithium tantalate (LiTaO{sub 3}) ferroelectrics bioactive?

    Energy Technology Data Exchange (ETDEWEB)

    Vilarinho, Paula Maria, E-mail: paula.vilarinho@ua.pt; Barroca, Nathalie; Zlotnik, Sebastian; Félix, Pedro; Fernandes, Maria Helena

    2014-06-01

    The use of functional materials, such as ferroelectrics, as platforms for tissue growth in situ or ex situ, is new and holds great promise. But the usage of materials in any bioapplication requires information on biocompatibility and desirably on bioactive behavior when bone tissue engineering is envisaged. Both requirements are currently unknown for many ferroelectrics. Herein the bioactivity of LiNbO{sub 3} and LiTaO{sub 3} is reported. The formation of apatite-like structures on the surface of LiNbO{sub 3} and LiTaO{sub 3} powders after immersion in simulated body fluid (SBF) for different soaking periods indicates their bioactive potential. The mechanism of apatite formation is suggested. In addition, the significant release of lithium ions from the ferroelectric powders in the very first minutes of soaking in SBF is examined and ways to overcome this likely hurdle addressed. - Highlights: • LiNbO{sub 3} and LiTaO{sub 3} are bioactive ferroelectrics. • Cauliflower apatite type structures indicative of in-vitro bioactivity of LiNbO{sub 3} and LiTaO{sub 3.} • Negative surface charges anchor Ca{sup 2+} to which PO{sub 4}{sup 3−} attracts forming apatite structure nuclei. • Use of ferroelectrics as platforms for tissue growth in situ or ex situ is new and holds great promise.

  13. Biological and bactericidal properties of Ag-doped bioactive glass in a natural extracellular matrix hydrogel with potential application in dentistry

    OpenAIRE

    Y-Y Wang; X Chatzistavrou; D Faulk; Badylak, S; Zheng, L; S. Papagerakis; Ge, L.; H. Liu; Papagerakis, P.

    2015-01-01

    The aim of this study was the fabrication and evaluation of a novel bioactive and bactericidal material, which could have applications in dentistry by supporting tissue regeneration and killing oral bacteria. Our hypothesis was that a new scaffold for pulp-dentin tissue engineering with enhanced antibacterial activity could be obtained by associating extracellular matrix derived from porcine bladder with an antibacterial bioactive glass. Our study combines in vitro approaches and ectopic impl...

  14. Bioactive compounds from northern plants.

    Science.gov (United States)

    Hohtola, Anja

    2010-01-01

    Northern conditions are characterised by long days with much light and low temperatures during the growing season. It has been chimed that herbs and berries grown in the north are stronger tasting compared to those of southern origin. The compounds imparting aroma and color to berries and herbs are secondary metabolites which in plants mostly act as chemical means of defense. Recently, the production of secondary metabolites using plant cells has been the subject of expanding research. Light intensity, photoperiod and temperature have been reported to influence the biosynthesis of many secondary metabolites. Native wild aromatic and medicinal plant species of different families are being studied to meet the needs of raw material for the expanding industry of e.g., health-promoting food products known as nutraceutics. There are already a large number of known secondary compounds produced by plants, but the recent advances in modern extraction and analysis should enable many more as yet unknown compounds to be found, characterised and utilised. Rose root (Rhodiola rosea) is a perennial herbaceous plant which inhabits mountain regions throughout Europe, Asia and east coastal regions of North America. The extract made from the rhizomes acts as a stimulant like the Ginseng root. Roseroot has been categorized as an adaptogen and is reported to have many pharmacological properties. The biologically active components of the extract are salitroside tyrosol and cinnamic acid glycosides (rosavin, rosarin, rosin). Round-leaved sundew (Drosera rotundifolia L.) has circumboreal distribution. It inhabits nutrient-poor, moist and sunny areas such as peat bogs and wetlands. Sundew leaves are collected from the wild-type for various medicinal preparations and can be utilized in treating e.g., as an important "cough-medicine" for different respiratory diseases. The antimicrobial activity of extracts of aerial parts against various bacteria has been investigated. Drosera produces

  15. Excipient Nanoemulsions for Improving Oral Bioavailability of Bioactives

    OpenAIRE

    Laura Salvia-Trujillo; Olga Martín-Belloso; David Julian McClements

    2016-01-01

    The oral bioavailability of many hydrophobic bioactive compounds found in natural food products (such as vitamins and nutraceuticals in fruits and vegetables) is relatively low due to their low bioaccessibility, chemical instability, or poor absorption. Most previous research has therefore focused on the design of delivery systems to incorporate isolated bioactive compounds into food products. However, a more sustainable and cost-effect approach to enhancing the functionality of bioactive com...

  16. Mannich reaction: A versatile and convenient approach to bioactive skeletons

    Indian Academy of Sciences (India)

    Selva Ganesan Subramaniapillai

    2013-05-01

    This review gives an insight into the recent applications of Mannich reaction and its variants in the construction of bioactive molecules. Emphasis is given to the Mannich reaction that provides bioactive molecules and/or modifies the property of an existing bioactive molecule. The role of Mannich reaction in the construction of antimalarial, antitumour, antimicrobial, antitubercular, antiinflammatory and anticonvulsant molecules and also the significance of aminoalkyl Mannich side chain on the biological property of molecules is discussed here.

  17. Isolation and characterization of regulatory peptides and bioactive compounds

    OpenAIRE

    Norberg, Åke

    2004-01-01

    Isolation of peptides and other bioactive compounds is an important and often necessary step to get the total information about their structures. This is demonstrated by a number of different characterizations in this thesis. Bioactive peptides and small organic molecules can act as signaling substances and messengers in multicellular organisms and are fundamental to higher forms of life. The following bioactive peptides and compounds were studied. 1) Different assays ca...

  18. Pressurised Fluid Extraction of Bioactive Species in Tree Barks : Analysis using Hyphenated Electrochemical Mass Spectrometric Detection

    OpenAIRE

    Co, Michelle

    2010-01-01

    Analytical chemistry has developed throughout time to meet current needs. At present, the interest in biorefinery is growing, due to environmental awareness and the depletion of fossil resources. Biomass from agricultural and forestry industries has proven to be excellent raw material for different processes. Biorefinering valuable species such as bioactive species from biomass, without compromising the primary process of the biomass is highly desirable. Pressurised fluid extraction (PFE) usi...

  19. Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations

    OpenAIRE

    Guimarães, Rafaela; Barros, Lillian; Dueñas, Montserrat; Ricardo C. Calhelha; Carvalho, Ana Maria; Santos-Buelga, Celestino; Queiroz, Maria João R. P.; Ferreira, Isabel C.F.R.

    2013-01-01

    Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterization of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour...

  20. Extracellular matrix formation in self-assembled minimalistic bioactive hydrogels based on aromatic peptide amphiphiles

    OpenAIRE

    ZHOU, MI; Ulijn, Rein V.; Gough, Julie E

    2014-01-01

    The hitherto inconsistency in clinical performance for engineered skin drives the current development of novel cell-scaffolding materials; one challenge is to only extract essential characteristics from the complex native ECM (extracellular matrix) and incorporate them into a scaffold with minimal complexity to support normal cell functions. This study involved small-molecule-based bioactive hydrogels produced by the co-assembly of two aromatic peptide amphiphiles: Fmoc-FF (Fluorenylmethoxyca...

  1. The investigation of some bioactive compounds and antioxidant properties of hawthorn (Crataegus monogyna subsp. monogyna Jacq)

    OpenAIRE

    Serhat KESER; Celik, Sait; Turkoglu, Semra; Yilmaz, Okkes; Turkoglu, Ismail

    2014-01-01

    Aim: The antioxidant and pharmacological effects of hawthorn have mainly been attributed to the polyphenolic contents. The aim of this research is to determine some bioactive compounds and antioxidant properties of hawthorn aqueous and ethanol extracts of leaves, flowers, and ripened fruits. Materials and Methods: For this purpose, antioxidant activities of extracts were assessed on DPPH•, ABTS•+, superoxide scavenging, reducing power and ferrous metal chelating activity assays and phenolic c...

  2. Exploratory research on bioactive natural products with a focus on biological phenomena

    OpenAIRE

    Uemura, Daisuke

    2010-01-01

    The discovery of new basic compounds holds the key for advancing material sciences. We have focused on the identification and characterization of natural key compounds that control biologically and physiologically intriguing phenomena. The discovery of new bioactive molecules, facilitated by a deeper understanding of nature, should advance our knowledge of biological processes and lead to new strategies to treat disease. The structure and function of natural compounds are sometimes unexpected...

  3. Electrophoretic Deposition of Composite Coatings with Bioactive Character and Drug Delivery Capability

    OpenAIRE

    Chen, Qiang

    2015-01-01

    In spite of notable success of metallic orthopedic prosthesis in clinical, their long-term survivability remains a major challenge due to the lack of osteoconductivity and risks associated with post-surgery infections and surface corrosion. Modification of implant surfaces with bioactive materials and antimicrobial agents is being intensively investigated to prevent these negative effects. In this project, electrophoretic deposition (EPD) as a convenient coating technique has been developed t...

  4. Bioactive Peptides from Muscle Sources: Meat and Fish

    Directory of Open Access Journals (Sweden)

    Catherine Stanton

    2011-08-01

    Full Text Available Bioactive peptides have been identified in a range of foods, including plant, milk and muscle, e.g., beef, chicken, pork and fish muscle proteins. Bioactive peptides from food proteins offer major potential for incorporation into functional foods and nutraceuticals. The aim of this paper is to present an outline of the bioactive peptides identified in the muscle protein of meat to date, with a focus on muscle protein from domestic animals and fish. The majority of research on bioactives from meat sources has focused on angiotensin-1-converting enzyme (ACE inhibitory and antioxidant peptides.

  5. Preliminary study in development of glass-ceramic based on SiO{sub 2}-LiO{sub 2} system, starting of different SiO{sub 2} starting powders; Um estudo preliminar do desenvolvimento de materiais vitroceramicos do sistema SiO{sub 2}-LiO{sub 2} obtidos a partir de diferentes fontes de silica

    Energy Technology Data Exchange (ETDEWEB)

    Daguano, J.K.M.F.; Santos, F.A.; Santos, C.; Marton, L.F.M.; Conte, R.A.; Rodrigues Junior, D. [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Escola de Engenharia de Lorena. Dept. de Materiais; Melo, F.C.L. [Centro Tecnico Aeroespacial (AMR/CTA/IAE), Sao Jose dos Campos, SP (Brazil). Instituto de Aeronautica e Espaco. Div. de Materiais

    2009-07-01

    In this work, lithium disilicate glass-ceramics were developed starting of the rice ash- SiO{sub 2} and Li{sub 2}CO{sub 3} powders. The results were compared with glass ceramics based on the lithium disilicate obtained by commercial SiO{sub 2} powders. Glass were melted at 1580 deg C, and annealed at 850 deg C. X-Ray diffraction and scanning electron microscopy were used for characterization of the materials, and hardness and fracture toughness were evaluated using Vickers indentation method. Glasses with amorphous structure were obtained in both materials. After annealing, 'rice-ash' samples presented Li{sub 2}SiO{sub 3} and residual SiO{sub 2} as crystalline phases. On the other side, commercial SiO{sub 2}- Samples presented only Li{sub 2}Si{sub 2}O{sub 5} as crystalline phases and the better results of hardness and fracture toughness. (author)

  6. Encapsulating fatty acid esters of bioactive compounds in starch

    Science.gov (United States)

    Lay Ma, Ursula Vanesa

    Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols

  7. The Fabrication and Characterization of PCL/Rice Husk Derived Bioactive Glass-Ceramic Composite Scaffolds

    Directory of Open Access Journals (Sweden)

    Farnaz Naghizadeh

    2014-01-01

    Full Text Available The present study was conducted to fabricate a 3D scaffold using polycaprolactone (PCL and silicate based bioactive glass-ceramic (R-SBgC. Different concentrations of R-SBgC prepared from rice husk ash (RHA were combined with PCL to fabricate a composite scaffold using thermally induced phase separation (TIPS method. The products were then characterized using SEM and EDX. The results demonstrated that R-SBgC in PCL matrix produced a bioactive material which has highly porous structure with interconnected porosities. There appears to be a relationship between the increase in R-SBgC concentration and increased material density and compressive modulus; however, increasing R-SBgC concentration result in reduced scaffold porosity. In conclusion, it is possible to fabricate a PCL/bioactive glass-ceramic composite from processed rice husk. Varying the R-SBgC concentrations can control the properties of this material, which is useful in the development of the ideal scaffold intended for use as a bone substitute in nonload bearing sites.

  8. In vitro study of manganese-doped bioactive glasses for bone regeneration

    International Nuclear Information System (INIS)

    A glass belonging to the system SiO2–P2O5–CaO–MgO–Na2O–K2O was modified by introducing two different amounts of manganese oxide (MnO). Mn-doped glasses were prepared by melt and quenching technique and characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) observation and energy dispersion spectrometry (EDS) analysis. In vitro bioactivity test in simulated body fluid (SBF) showed a slight decrease in the reactivity kinetics of Mn-doped glasses compared to the glass used as control; however the glasses maintained a good degree of bioactivity. Mn-leaching test in SBF and minimum essential medium (MEM) revealed fluctuating trends probably due to a re-precipitation of Mn compounds during the bioactivity process. Cellular tests showed that all the Mn-doped glasses, up to a concentration of 50 μg/cm2 (μg of glass powders/cm2 of cell monolayer), did not produce cytotoxic effects on human MG-63 osteoblasts cultured for up to 5 days. Finally, biocompatibility tests demonstrated a good osteoblast proliferation and spreading on Mn-doped glasses and most of all that the Mn-doping can promote the expression of alkaline phosphatase (ALP) and some bone morphogenetic proteins (BMPs). - Highlights: • Novel bioactive glasses doped with manganese were prepared. • Mn-doped bioactive glasses were not cytotoxic towards human MG-63 osteoblasts. • The Mn introduction promotes the expression of ALP and bone morphogenetic proteins. • Mn-doped glass may be a promising material for bone regeneration procedures

  9. In vitro study of manganese-doped bioactive glasses for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Miola, Marta, E-mail: marta.miola@polito.it [Applied Science and Technology Department, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy); Brovarone, Chiara Vitale [Applied Science and Technology Department, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy); Maina, Giovanni [Department of Clinical and Biological Sciences, University of Turin, Via Zuretti 29, 10126 Turin (Italy); Rossi, Federica [Department of Public Health and Pediatric Sciences, Piazza Polonia, 94, 10126 Torino (Italy); Bergandi, Loredana; Ghigo, Dario [Department of Oncology, University of Turin, Via Santena 5/bis, 10126 Turin (Italy); Saracino, Silvia; Maggiora, Marina; Canuto, Rosa Angela; Muzio, Giuliana [Department of Clinical and Biological Sciences, University of Turin, Corso Raffaello 30, 10125 Turin (Italy); Vernè, Enrica [Applied Science and Technology Department, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Turin (Italy)

    2014-05-01

    A glass belonging to the system SiO{sub 2}–P{sub 2}O{sub 5}–CaO–MgO–Na{sub 2}O–K{sub 2}O was modified by introducing two different amounts of manganese oxide (MnO). Mn-doped glasses were prepared by melt and quenching technique and characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) observation and energy dispersion spectrometry (EDS) analysis. In vitro bioactivity test in simulated body fluid (SBF) showed a slight decrease in the reactivity kinetics of Mn-doped glasses compared to the glass used as control; however the glasses maintained a good degree of bioactivity. Mn-leaching test in SBF and minimum essential medium (MEM) revealed fluctuating trends probably due to a re-precipitation of Mn compounds during the bioactivity process. Cellular tests showed that all the Mn-doped glasses, up to a concentration of 50 μg/cm{sup 2} (μg of glass powders/cm{sup 2} of cell monolayer), did not produce cytotoxic effects on human MG-63 osteoblasts cultured for up to 5 days. Finally, biocompatibility tests demonstrated a good osteoblast proliferation and spreading on Mn-doped glasses and most of all that the Mn-doping can promote the expression of alkaline phosphatase (ALP) and some bone morphogenetic proteins (BMPs). - Highlights: • Novel bioactive glasses doped with manganese were prepared. • Mn-doped bioactive glasses were not cytotoxic towards human MG-63 osteoblasts. • The Mn introduction promotes the expression of ALP and bone morphogenetic proteins. • Mn-doped glass may be a promising material for bone regeneration procedures.

  10. Optimization of calcium chloride content on bioactivity and mechanical properties of white Portland cement

    International Nuclear Information System (INIS)

    This research investigates the optimization of calcium chloride content on the bioactivity and mechanical properties of white Portland cement. Calcium chloride was used as an addition of White Portland cement at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by weight. Calcium chloride was dissolved in sterile distilled water and blended with White Portland cement using a water to cement ratio of 0.5. Analysis of the bioactivity and pH of white Portland cement pastes with calcium chloride added at various amounts was carried out in simulated body fluid. Setting time, density, compressive strength and volume of permeable voids were also investigated. The characteristics of cement pastes were examined by X-ray diffractometer and scanning electron microscope linked to an energy-dispersive X-ray analyzer. The result indicated that the addition of calcium chloride could accelerate the hydration of white Portland cement, resulting in a decrease in setting time and an increase in early strength of the pastes. The compressive strength of all cement pastes with added calcium chloride was higher than that of the pure cement paste, and the addition of calcium chloride at 8 wt.% led to achieving the highest strength. Furthermore, white Portland cement pastes both with and without calcium chloride showed well-established bioactivity with respect to the formation of a hydroxyapatite layer on the material within 7 days following immersion in simulated body fluid; white Portland cement paste with added 3%CaCl2 exhibited the best bioactivity. - Highlights: ► Optimization CaCl2 content on the bioactivity and mechanical properties. ► CaCl2 was used as an addition at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by weight. ► CaCl2 resulted in a decrease in setting time and an increase in early strength. ► Addition of 3%CaCl2 exhibited the optimum formation of hydroxyapatite.

  11. HPLC ANALYSIS OF BIOACTIVE COMPOUNDS IN TEN DIFFERENT WILD TYPE UNDER-UTILIZED LEGUME GRAINS

    Directory of Open Access Journals (Sweden)

    Vellingiri Vadivel and Hans Konrad Biesalski

    2010-05-01

    Full Text Available In recent years, many food industries have been initiated the formulation of nutraceutical/functional foods by incorporating the bioactive ingredients for the prevention/treatment of certain chronic diseases. In this connection, certain promising wild type under-utilized legume grains received more attention, since they are naturally a rich source of L-Dopa (precursor of dopamine and certain bioactive compounds including phenolics, tannins and phytic acid. In the present study, seed materials of certain promising wild type under-utilized food legume grains such as Abrus precatorius L., Acacia leucopholea Willd, Bauhinia varigata L., Canavalia gladiata (Jacq. DC., Cassia floribunda Cav., Entada scandens Benth., Indigofera linifolia (L.f. Retz., Mucuna monosperma DC. Ex Wight., Sesbania bispinosa (Jacq. Wight. and Tamarindus indica L., collected from Eastern and Western Ghats of South India, were investigated for certain bioactive compounds through HPLC technique. All the analysed samples were found to constitute a viable source of total free phenolics (4.23 – 8.75 g/100 g DM, tannins (1.04 – 5.41 g /100 g DM, L-Dopa (1.17 – 5.34 g/100 g DM and phytic acid (0.96 – 2.74 g/100 g DM and also the newly developed HPLC procedures were proven to be sensitive enough to detect these bioactive compounds even at tracer level. Further, such wild type legume grains could be recommended as a natural source of bioactive compounds in the dietary management of certain chronic diseases such as Parkinsonism, diabetes, obesity, cardiovascular diseases, cancer etc.

  12. Novel ingredients from brewers' spent grain - bioactivity in cell culture model systems and bioactivity retention in fortified food products

    OpenAIRE

    McCarthy, Aoife Louise

    2013-01-01

    Functional food ingredients, with scientifically proven and validated bioactive effects, present an effective means of inferring physiological health benefits to consumers to reduce the risk of certain diseases. The search for novel bioactive compounds for incorporation into functional foods is particularly active, with brewers’ spent grain (BSG, a brewing industry co-product) representing a unique source of potentially bioactive compounds. The DNA protective, antioxidant and immunomodulatory...

  13. Bioactive glass coupling with natural polyphenols: Surface modification, bioactivity and anti-oxidant ability

    Science.gov (United States)

    Cazzola, Martina; Corazzari, Ingrid; Prenesti, Enrico; Bertone, Elisa; Vernè, Enrica; Ferraris, Sara

    2016-03-01

    Polyphenols are actually achieving an increasing interest due to their potential health benefits, such as antioxidant, anticancer, antibacterial and bone stimulation abilities. However their poor bioavailability and stability hamper an effective clinical application as therapeutic principles. The opportunity to couple these biomolecules with synthetic biomaterials, in order to obtain local delivery at the site of interest, improve their bioavailability and stability and combine their properties with the ones of the substrate, is a challenging opportunity for the biomedical research. A silica based bioactive glass, CEL2, has been successfully coupled with gallic acid and natural polyphenols extracted from red grape skins and green tea leaves. The effectiveness of grafting has been verified by means of XPS analyses and the Folin&Ciocalteu tests. In vitro bioactivity has been investigated by soaking in simulated body fluid (SBF). Surface modification after functionalization and early stage reactivity in SBF have been studied by means of zeta potential electrokinetic measurements in KCl and SBF. Finally the antioxidant properties of bare and modified bioactive glasses has been investigated by means of the evaluation of free radical scavenging activity by Electron Paramagnetic Resonance (EPR)/spin trapping technique after UV photolysis of H2O2 highlighting scavenging activity of the bioactive glass.

  14. Significant degradability enhancement in multilayer coating of polycaprolactone-bioactive glass/gelatin-bioactive glass on magnesium scaffold for tissue engineering applications

    International Nuclear Information System (INIS)

    Highlights: • PCL-BaG/Gel-BaG coating was applied on the surface of Mg scaffolds. • Mg scaffold/PCL-BaG/Gel-BaG presented improved biodegradation resistance. • Mg scaffold coated with the PCL-BaG layer indicated better bioactivity. - Abstract: Magnesium (Mg) is a promising candidate to be used in medical products especially as bone tissue engineering scaffolds. The main challenge for using Mg in biomedical applications is its high degradation rate in the body. For this reason, in this study, a multilayer polymeric layer composed of polycaprolactone (PCL) and gelatin (Gel) reinforced with bioactive glass (BaG) particles has been applied on the surface of Mg scaffolds. The materials characteristics of uncoated Mg scaffold, Mg scaffold coated only with PCL-BaG and Mg scaffold coated with PCL-BaG and Gel-BaG have been analyzed and compared in detail. Scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) were utilized for microstructural studies. In vitro bioactivity and biodegradation evaluations were carried out by submerging the scaffolds in simulated body fluid (SBF) at pre-determined time points. The results demonstrated that Mg scaffold coated with PCL-BaG and Gel-BaG exhibited significant improvement in biodegradability

  15. Significant degradability enhancement in multilayer coating of polycaprolactone-bioactive glass/gelatin-bioactive glass on magnesium scaffold for tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Yazdimamaghani, Mostafa [School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States); School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Razavi, Mehdi [School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Vashaee, Daryoosh [Electrical and Computer Engineering Department, North Carolina State University, Raleigh, NC 27606 (United States); Pothineni, Venkata Raveendra [Biomaterials and Advanced Drug Delivery Laboratory, Stanford University, Palo Alto, CA 94305 (United States); Rajadas, Jayakumar [Biomaterials and Advanced Drug Delivery Laboratory, Stanford University, Palo Alto, CA 94305 (United States); Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, CA 94305 (United States); Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA 94305 (United States); Tayebi, Lobat, E-mail: lobat.tayebi@marquette.edu [School of Materials Science and Engineering, Helmerich Advanced Technology Research Center, Oklahoma State University, Tulsa, OK 74106 (United States); Biomaterials and Advanced Drug Delivery Laboratory, Stanford University, Palo Alto, CA 94305 (United States); Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI 53233 (United States)

    2015-05-30

    Highlights: • PCL-BaG/Gel-BaG coating was applied on the surface of Mg scaffolds. • Mg scaffold/PCL-BaG/Gel-BaG presented improved biodegradation resistance. • Mg scaffold coated with the PCL-BaG layer indicated better bioactivity. - Abstract: Magnesium (Mg) is a promising candidate to be used in medical products especially as bone tissue engineering scaffolds. The main challenge for using Mg in biomedical applications is its high degradation rate in the body. For this reason, in this study, a multilayer polymeric layer composed of polycaprolactone (PCL) and gelatin (Gel) reinforced with bioactive glass (BaG) particles has been applied on the surface of Mg scaffolds. The materials characteristics of uncoated Mg scaffold, Mg scaffold coated only with PCL-BaG and Mg scaffold coated with PCL-BaG and Gel-BaG have been analyzed and compared in detail. Scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) were utilized for microstructural studies. In vitro bioactivity and biodegradation evaluations were carried out by submerging the scaffolds in simulated body fluid (SBF) at pre-determined time points. The results demonstrated that Mg scaffold coated with PCL-BaG and Gel-BaG exhibited significant improvement in biodegradability.

  16. Control of Ag nanoparticle distribution influencing bioactive and antibacterial properties of Ag-doped mesoporous bioactive glass particles prepared by spray pyrolysis.

    Science.gov (United States)

    Shih, Shao-Ju; Tzeng, Wei-Lung; Jatnika, Rifqi; Shih, Chi-Jen; Borisenko, Konstantin B

    2015-05-01

    Mesoporous bioactive glasses (MBGs) have become important bone implant materials because of their high specific surface area resulting in high bioactivity. Doping MBGs with Ag removes one of the remaining challenges to their applications, namely their lack of intrinsic antibacterial properties. In present work we demonstrate that Ag-doped MBGs can be prepared in one-step spray pyrolysis (SP) process. The SP preparation method offers the advantages of short processing times and continuous production over the sol-gel method previously used to prepare MBGs. Using scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction we demonstrate that the synthesized MBG particles have amorphous structure with nanocrystalline Ag inclusions. The scanning transmission electron microscopy-X-ray energy dispersive spectrometry of cross-sectional samples shows that the distribution of the Ag dopant nanoparticles within MBGs can be controlled by using the appropriate formulation of the precursors. The distribution of the Ag dopant nanoparticles within the MBG particles was found to affect their surface areas, bioactivities and antibacterial properties. Based on the observations, we propose a mechanism describing MBG particle formation and controlling dopant distribution. PMID:25171327

  17. [Study on a new type of apatite/wollastonite porous bioactive glass-ceramic].

    Science.gov (United States)

    Yang, Weizhong; Zhou, Dali; Yin, Guangfu; Chen, Huaiqing; Xiao, Bin; Zhang, Yun

    2004-12-01

    A novel glass-ceramic has been derived from sol-gel process. In this study XRD and FTIR analysis confirmed that the main crystalline phases of the material were hydroxyapatite/fluoroapatite [Ca10(PO4)6(OH,F)] and beta-wollastonite[beta-CaSiO3]; SEM examination showed that the microstructure contained many micro pores of 2-3 microm. After pore-forming, the material possessed good macro porous structure: the size of macro pores was 300-400 microm in diameter, and pores interconnected each other. Bioactivity of the material was preliminarily evaluated in the simulate body fluid. SEM observation revealed that a lot of apatite granules had been formed on the surface of the material after soaking within 7 days. Result shows that the novel sol-gel derived apatite-wollastonite-containing glass-ceramic has good bioactivity. Porous materials have suitable microstructure as well as macrostructure, which make it an excellent material to be used as bone-repairing materials and bone tissue engineering carrier materials. PMID:15646331

  18. Bioactive surfaces with atomic layer deposition

    OpenAIRE

    Kvalvik, Julie Nitsche

    2015-01-01

    The overall goal of this work has been to make bioactive surfaces with atomic layer deposition (ALD). To do this, a new ALD system with titanium tetraisopropoxide (TTIP) and lysine as precursors was developed with emphasis on studying the effects of pulsing times and deposition temperatures. TTIP was chosen as titanium is regarded to be biocompatible and lysine was chosen as poly-L-lysine is a part of the extra-cellular matrix (ECM) and hence affects cell adhesion. The effect of a water pulse...

  19. Marine Nucleosides: Structure, Bioactivity, Synthesis and Biosynthesis

    Directory of Open Access Journals (Sweden)

    Ri-Ming Huang

    2014-12-01

    Full Text Available Nucleosides are glycosylamines that structurally form part of nucleotide molecules, the building block of DNA and RNA. Both nucleosides and nucleotides are vital components of all living cells and involved in several key biological processes. Some of these nucleosides have been obtained from a variety of marine resources. Because of the biological importance of these compounds, this review covers 68 marine originated nucleosides and their synthetic analogs published up to June 2014. The review will focus on the structures, bioactivities, synthesis and biosynthetic processes of these compounds.

  20. Influence of mesostructuration on the reactivity of bioactive glasses in biological medium: a PIXE-RBS study

    OpenAIRE

    Soulié, Jérémy; Lao, Jonathan; Jallot, Edouard; Nedelec, Jean-Marie

    2012-01-01

    Building mesostructured biomaterials is a challenging and exciting task that has attracted much attention because of their use as drug carriers or drug delivery systems. In the case of bioactive materials, the mesostructuration can also deeply impact their physico-chemical properties and the reactivity. In this study, we show how highly ordered mesoporosity influences the early steps of the biomineralization process and the reactivity in binary (SiO2–CaO) and ternary (SiO2–CaO–P2O5) bioactive...

  1. Preparation and characterization of bioactive and degradable composites containing ordered mesoporous calcium-magnesium silicate and poly(L-lactide)

    International Nuclear Information System (INIS)

    Highlights: • Mesoporous calcium-magnesium silicate and poly(L-lactide) composite was fabricated. • The composite has good hydrophilicity, in vitro degradation and bioactivity. • The composite could support cell attachment, proliferation and differentiation. - Abstract: Polylactide (PLA) and its copolymers have been widely used for bone tissue regeneration. In this study, a bioactive composite of ordered mesoporous calcium–magnesium silicate (m-CMS) and poly(L-lactide) (PLLA) was fabricated by melt blending method. The results indicated that the m-CMS particles were entrapped by polymer phase, and crystallinity of PLLA significantly decreased while the thermal stability of the m-CMS/PLLA composites was not obviously affected by addition of the m-CMS into PLLA. In addition, compared to PLLA, incorporation of the m-CMS into PLLA significantly improved the hydrophilicity, in vitro degradability and bioactivity (apatite-formation ability) of the m-CMS/PLLA composite, which were m-CMS content dependent. Moreover, it was found that incorporation of the m-CMS into PLLA could neutralize the acidic degradation by-products and thus compensated for the decrease of pH value. In cell culture experiments, the results showed that the composite enhanced attachment, proliferation and alkaline phosphatase activity (ALP) of MC3T3-E1 cells, which were m-CMS content dependent. The results indicated that the addition of bioactive materials to PLLA could result in a composite with improved properties of hydrophilicity, degradability, bioactivity and cytocompatibility

  2. Preparation and characterization of bioactive and degradable composites containing ordered mesoporous calcium-magnesium silicate and poly(L-lactide)

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Jiajin [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China); Dong, Xieping, E-mail: jxzhyxh@163.com [Department of Orthopaedic Surgery, Jiangxi People' s Hospital, Nanchang 330006 (China); Ma, Xuhui [Polymer Science (Shenzhen) New Materials Co., Ltd., Shenzhen 518101 (China); Tang, Songchao, E-mail: schtang@ecust.edu.cn [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China); Wu, Zhaoying; Xia, Ji; Wang, Quanxiang; Wang, Yutao; Wei, Jie [Key Shanghai Key Laboratory of Advanced Polymeric Materials, East China University of Science and Technology, Shanghai 200237 (China)

    2014-10-30

    Highlights: • Mesoporous calcium-magnesium silicate and poly(L-lactide) composite was fabricated. • The composite has good hydrophilicity, in vitro degradation and bioactivity. • The composite could support cell attachment, proliferation and differentiation. - Abstract: Polylactide (PLA) and its copolymers have been widely used for bone tissue regeneration. In this study, a bioactive composite of ordered mesoporous calcium–magnesium silicate (m-CMS) and poly(L-lactide) (PLLA) was fabricated by melt blending method. The results indicated that the m-CMS particles were entrapped by polymer phase, and crystallinity of PLLA significantly decreased while the thermal stability of the m-CMS/PLLA composites was not obviously affected by addition of the m-CMS into PLLA. In addition, compared to PLLA, incorporation of the m-CMS into PLLA significantly improved the hydrophilicity, in vitro degradability and bioactivity (apatite-formation ability) of the m-CMS/PLLA composite, which were m-CMS content dependent. Moreover, it was found that incorporation of the m-CMS into PLLA could neutralize the acidic degradation by-products and thus compensated for the decrease of pH value. In cell culture experiments, the results showed that the composite enhanced attachment, proliferation and alkaline phosphatase activity (ALP) of MC3T3-E1 cells, which were m-CMS content dependent. The results indicated that the addition of bioactive materials to PLLA could result in a composite with improved properties of hydrophilicity, degradability, bioactivity and cytocompatibility.

  3. In vitro studies of degradation and bioactivity of aliphatic polyester composites

    Science.gov (United States)

    Chouzouri, Georgia

    In spite of numerous publications on the potential use of combinations of aliphatic polyester composites containing bioactive fillers for bone regeneration, little information exists on the combined in vitro mechanisms involving simultaneously diffusion for polymer degradation and bioactivity through nucleation and growth of apatite in simulated body fluid (SBF) solution. The objective of this study is to contribute to the understanding of the fundamentals in designing non-porous, solid materials for bone regeneration, from experimental data along with their engineering interpretation. Bioactivity, in terms of apatite growth, was assessed through several experimental methods such as scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray-diffraction (XRD) and changes in ion concentration. In the case of the six neat fillers evaluated, the filler shape, form and chemical structure showed significant differences in bioactivity response. Bioglass and calcium silicate fillers showed faster nucleation and growth rates in the screening experiments. Composites at 30% by weight filler were prepared by solution and/or melt mixing. Polycaprolactone (PCL) composites containing five different fillers were evaluated. Solution processed PCL/calcium silicate (CS) samples showed faster bioactivity, as determined by apatite growth, compared to melt mixed samples. The onset time for bioactivity was different for all PCL composites. The limited bioactivity in the PCL composites over longer periods of time could be attributed to the PCL hydrophobicity leading to a slow polymer degradation rate, and also to the lack of SBF replenishment. For both polylactic acid (PLA) composites containing CS and bioglass, significant growth was observed after one week and in the case of CS was still evident after four weeks immersion. However, at prolonged time periods no further bioactivity was observed, although ion release results indicated a faster release rate that would

  4. Quantification and bioaccessibility of california pistachio bioactives.

    Science.gov (United States)

    Liu, Yuntao; Blumberg, Jeffrey B; Chen, C-Y Oliver

    2014-02-19

    The content of carotenoids, chlorophylls, phenolics, and tocols in pistachios ( Pistacia vera L.) has not been methodically quantified. The objective of this study was to first optimize extraction protocols for lipophilic nutrients and then quantify the content of two phenolic acids, nine flavonoids, four carotenoids, two chlorophylls, and three tocols in the skin, nutmeat, and whole nut of California pistachios. The dominant bioactives in whole pistachios are lutein [42.35 μg/g fresh weight (FW)], chlorophyll a (142.24 μg/g FW), γ-tocopherol (182.20 μg/g FW), flavan-3-ols (catechins) (199.18 μg/g FW), luteolin (217.89 μg/g FW), myricetin (135.18 μg/g FW), and cyanidin-3-galactose (38.34 μg/g FW) in each nutrient class. Most phenolics are present in the skin, while the lipophilic nutrients are dominantly present in the nutmeat. Digestion with a gastrointestinal mimic showed <10% of most hydrophilic compounds are released from pistachio matrices. In conclusion, 9 lipophilic and 11 hydrophilic bioactives in pistachios are systematically quantified. PMID:24460079

  5. Bioactivity and chemical ecology of some intertidal animals

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A.H.; Shirwaikar, P.

    stream_size 7 stream_content_type text/plain stream_name Bioactive_Com_Mar_Org_1991_29.pdf.txt stream_source_info Bioactive_Com_Mar_Org_1991_29.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  6. Bioactive compounds: Safety and efficacy (Consensus Meeting - Part II)

    NARCIS (Netherlands)

    Biesalski, H.K.; Dragsted, L.O.; Elmadfa, I.; Grossklaus, R.; Müller, M.R.; Schrenk, D.; Walter, P.; Weber, P.

    2009-01-01

    The efficacy and safety of bioactive compounds depend on a few known and unknown parameters. What is a physiologic dose and how can that dose be defined in cases of bioactive compounds with a poor knowledge of supply and distribution? What safety sets are needed? How can individual aspects such as p

  7. Preparation, in vitro mineralization and osteoblast cell response of electrospun 13-93 bioactive glass nanofibers.

    Science.gov (United States)

    Deliormanlı, Aylin M

    2015-08-01

    In this study, silicate based 13-93 bioactive glass fibers were prepared through sol-gel processing and electrospinning technique. A precursor solution containing poly (vinyl alcohol) and bioactive glass sol was used to produce fibers. The mixture was electrospun at a voltage of 20 kV by maintaining tip to a collector distance of 10 cm. The amorphous glass fibers with an average diameter of 464±95 nm were successfully obtained after calcination at 625 °C. Hydroxyapatite formation on calcined 13-93 fibers was investigated in simulated body fluid (SBF) using two different fiber concentrations (0.5 and 1 mg/ml) at 37 °C. When immersed in SBF, conversion to a calcium phosphate material showed a strong dependence on the fiber concentration. At 1mg/ml, the surface of the fibers converted to the hydroxyapatite-like material in SBF only after 30 days. At lower solid concentrations (0.5 mg/ml), an amorphous calcium phosphate layer formation was observed followed by the conversion to hydroxyapatite phase after 7 days of immersion. The XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) assay was conducted to evaluate the osteoblast cell response to the bioactive glass fibers. PMID:26042714

  8. Interaction of bioactive glasses with peritoneal macrophages and monocytes in vitro.

    Science.gov (United States)

    Bosetti, M; Hench, L; Cannas, M

    2002-04-01

    Macrophage activation was analyzed following exposure to pure, crystalline alpha-quartz powders, two bioactive gel-glass powders of different compositions, and a melt-derived glass, 45S5 Bioglass. The release of reactive oxygen metabolites (chemiluminescence test), modifications of cell morphology, the amount of tumor necrosis factor alpha (TNFalpha) secreted, and the amount of TNFalpha mRNA expression were evaluated. The 45S5 Bioglass powders elicited the highest chemiluminescence response while the two solgel glasses had a lower response with less of an oxidative burst difference between them. Particulate bioactive glasses are actively ingested by mouse peritoneal macrophages, and only the 58S solgel glass had a moderate toxic effect on the macrophages. Macrophage cell morphology showed increased size and cell spreading, consistent with the high level of cytokine secretion induced by 45S5 Bioglass. The 45S5 Bioglass powders led to an increased release of TNFalpha and expression of TNFalpha mRNA relative to unstimulated and control treated monocytes. Bioactive glasses (and particularly 45S5 Bioglass) that in vivo induce rapid bone growth appear to activate an autocrine-like process in which the response evoked by the material (for example monocyte and macrophage activation with cytokine production) enhances subsequent interactions with cells in contact with the material. PMID:11835162

  9. Fabrication of 13-93 bioactive glass scaffolds for bone tissue engineering using indirect selective laser sintering

    Energy Technology Data Exchange (ETDEWEB)

    Kolan, Krishna C R; Leu, Ming C [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, MO (United States); Hilmas, Gregory E [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO (United States); Brown, Roger F [Department of Biological Sciences, Missouri University of Science and Technology, Rolla, MO (United States); Velez, Mariano, E-mail: kkd7b@mail.mst.edu, E-mail: mleu@mst.edu [Mo-Sci Corporation, Rolla, MO (United States)

    2011-06-15

    Bioactive glasses are promising materials for bone scaffolds due to their ability to assist in tissue regeneration. When implanted in vivo, bioactive glasses can convert into hydroxyapatite, the main mineral constituent of human bone, and form a strong bond with the surrounding tissues, thus providing an advantage over polymer scaffold materials. Bone scaffold fabrication using additive manufacturing techniques can provide control over pore interconnectivity during fabrication of the scaffold, which helps in mimicking human trabecular bone. 13-93 glass, a third-generation bioactive material designed to accelerate the body's natural ability to heal itself, was used in the research described herein to fabricate bone scaffolds using the selective laser sintering (SLS) process. 13-93 glass mixed with stearic acid (as the polymer binder) by ball milling was used as the powder feedstock for the SLS machine. The fabricated green scaffolds underwent binder burnout to remove the stearic acid binder and were then sintered at temperatures between 675 deg. C and 695 deg. C. The sintered scaffolds had pore sizes ranging from 300 to 800 {mu}m with 50% apparent porosity and an average compressive strength of 20.4 MPa, which is excellent for non-load bearing applications and among the highest reported for an interconnected porous scaffold fabricated with bioactive glasses using the SLS process. The MTT labeling experiment and measurements of MTT formazan formation are evidence that the rough surface of SLS scaffolds provides a cell-friendly surface capable of supporting robust cell growth.

  10. Fabrication of 13-93 bioactive glass scaffolds for bone tissue engineering using indirect selective laser sintering

    International Nuclear Information System (INIS)

    Bioactive glasses are promising materials for bone scaffolds due to their ability to assist in tissue regeneration. When implanted in vivo, bioactive glasses can convert into hydroxyapatite, the main mineral constituent of human bone, and form a strong bond with the surrounding tissues, thus providing an advantage over polymer scaffold materials. Bone scaffold fabrication using additive manufacturing techniques can provide control over pore interconnectivity during fabrication of the scaffold, which helps in mimicking human trabecular bone. 13-93 glass, a third-generation bioactive material designed to accelerate the body's natural ability to heal itself, was used in the research described herein to fabricate bone scaffolds using the selective laser sintering (SLS) process. 13-93 glass mixed with stearic acid (as the polymer binder) by ball milling was used as the powder feedstock for the SLS machine. The fabricated green scaffolds underwent binder burnout to remove the stearic acid binder and were then sintered at temperatures between 675 deg. C and 695 deg. C. The sintered scaffolds had pore sizes ranging from 300 to 800 μm with 50% apparent porosity and an average compressive strength of 20.4 MPa, which is excellent for non-load bearing applications and among the highest reported for an interconnected porous scaffold fabricated with bioactive glasses using the SLS process. The MTT labeling experiment and measurements of MTT formazan formation are evidence that the rough surface of SLS scaffolds provides a cell-friendly surface capable of supporting robust cell growth.

  11. Crystallization of pyroxene phases and physico-chemical properties of glass-ceramics based on Li{sub 2}O–Cr{sub 2}O{sub 3}–SiO{sub 2} eutectic glass system

    Energy Technology Data Exchange (ETDEWEB)

    Salman, S.M.; Salama, S.N.; Abo-Mosallam, H.A., E-mail: abomosallam@yahoo.com.au

    2015-01-15

    The crystallization characteristics, crystalline phase assemblages and solid solution phases developed due to thermally crystallized glasses based on the Li{sub 2}SiO{sub 3}–Li{sub 2}Si{sub 2}O{sub 5}–LiCrSi{sub 2}O{sub 6} (1028 ± 3 °C) eutectic glass system by replacing some trivalent oxides instead of Cr{sub 2}O{sub 3} were investigated. The microhardness and chemical durability of the glass-ceramics were also determined. Lithium meta and disilicate (Li{sub 2}SiO{sub 3} and Li{sub 2}Si{sub 2}O{sub 5}), lithium gallium silicate (LiGaSiO{sub 4}), and varieties of pyroxene phases, including Cr-pyroxene phase, i.e. lithium-kosmochlor (LiCrSi{sub 2}O{sub 6}), lithium aluminum silicate (LiAlSi{sub 2}O{sub 6}), lithium indium silicate (LiInSi{sub 2}O{sub 6}) and pyroxene solid solution of Li-aegerine type [Li (Fe{sub 0.5}, Cr{sub 0.5}) Si{sub 2}O{sub 6}] were the main crystalline phases formed in the crystallized glasses. There is no evidence for the formation of solid solution or liquid immiscibility gaps between LiAlSi{sub 2}O{sub 6} or LiInSi{sub 2}O{sub 6} phases and LiCrSi{sub 2}O{sub 6} phase. However, LiCrSi{sub 2}O{sub 6} and LiFeSi{sub 2}O{sub 6} components were accommodated in the pyroxene structure under favorable conditions of crystallization to form monomineralic pyroxene solid solution phase of the probably formula [Li (Fe{sub 0.5}, Cr{sub 0.5}) Si{sub 2}O{sub 6}]. The type and compatibility of the crystallized phases are discussed in relation to the compositional variation of the glasses and heat-treatment applied. The microhardness values of the crystalline materials ranged between 5282 and 6419 MPa while, the results showed that the chemical stability of the glass-ceramics was better in alkaline than in acidic media. - Highlights: • Glass ceramics based on Li{sub 2}O–Cr{sub 2}O{sub 3}–SiO{sub 2} eutectic (1028 ± 3 °C) glass were prepared. • LiCrSi{sub 2}O{sub 6} and LiFeSi{sub 2}O{sub 6} phases form monomineralic pyroxene solid

  12. Recent Advances in Separation of Bioactive Natural Products

    Institute of Scientific and Technical Information of China (English)

    任其龙; 邢华斌; 鲍宗必; 苏宝根; 杨启炜; 杨亦文; 张治国

    2013-01-01

    Bioactive natural products are a main source of new drugs, functional foods and food additives. The separation of bioactive natural products plays an important role in transformation and use of biomass. The isolation and purification of bioactive principle from a complex matrix is often inherent bottleneck for the utilization of natural products, so a series of extraction and separation techniques have been developed. This review covers recent advances in the separation of bioactive natural products with an emphasis on their solubility and diffusion coeffi-cients, recent extraction techniques and isolation techniques. This overview of recent technological advances, dis-cussion of pertinent problems and prospect of current methodologies in the separation of bioactive natural products may provide a driving force for development of novel separation techniques.

  13. Preparation of novel bioactive nano-calcium phosphate-hydrogel composites

    Energy Technology Data Exchange (ETDEWEB)

    Juhasz, Judith A; Best, Serena M; Bonfield, William, E-mail: jaj33@cam.ac.u [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)

    2010-02-15

    Nano-sized hydroxyapatite (nHA) and carbonate-substituted hydroxyapatite (nCHA) particles were incorporated into a poly-2-hydroxyethylmethacrylate/polycaprolactone (PHEMA/PCL) hydrogel at a filler content of 10 wt%. Fourier transform infrared absorption, transmission electron microscopy, x-ray diffraction and scanning electron microscopy were used to analyse the physical and chemical characteristics of the calcium phosphate fillers and resultant composites. Nano-sized calcium phosphate particles were produced with a needle-like morphology, average length of 50 nm and an aspect ratio of 3. The nanoparticles were uniformly distributed in the polymer matrix. The addition of both HA and CHA in nano-form enhanced the bioactivity and biocompatibility of the PHEMA/PCL matrix. The carbonate-substitution has allowed for improved bioactivity and biocompatibility of the resultant composite, indicating the potential of this material for use in bone tissue engineering.

  14. Bioactive glasses-incorporated, core-shell-structured polypeptide/polysaccharide nanofibrous hydrogels.

    Science.gov (United States)

    Chen, Jian; Chen, Xiaoyi; Yang, Xianyan; Han, Chunmao; Gao, Changyou; Gou, Zhongru

    2013-01-30

    Although the synthetic hydrogel materials capable of accelerating wound healing are being developed at a rapid pace, achieving inorganic-organic hybrid at nanoscale dimension in nanofibrous hydrogels is still a great challenge because of its notorious brittleness and microstructural stability in wet state. Here, we developed a new nanofibrous gelatin/bioactive glass (NF-GEL/BG) composite hydrogel by phase separation method and followed by arming the nanofibers network with counterionic chitosan-hyaluronic acid pairs for improving microstructural and thermal integrity. We achieve this feature by carrying an optimal balance of charges that allows the inorganic ion release in aqueous solution without minimal structure collapse. Therefore, such NF-GEL-based, polysaccharide-crosslinked bioactive hydrogel could afford a close biomimicry to the fibrous nanostructure and constituents of the hierarchically organized natural soft tissues to facilitate chronic, nonhealing wound treatment. PMID:23218343

  15. Anodic fabrication and bioactivity of Nb-doped TiO2 nanotubes.

    Science.gov (United States)

    Ding, Dongyan; Ning, Congqin; Huang, Lin; Jin, Fangchun; Hao, Yongqiang; Bai, Shuo; Li, Yan; Li, Ming; Mao, Dali

    2009-07-29

    We report anodic formation of Ti-Nb-O nanotubes on top of a Ti35Nb alloy, and in vitro bioactivity and stem cell response of the anodic nanotubes. It was found that the amorphous Ti-Nb-O nanotubes presented a significantly enhanced in vitro bioactivity (in simulated body fluids) compared to those of undoped TiO2 nanotubes and porous Ti-Nb-O without nanotubular structure. Similar to undoped TiO2 nanotubes, the Ti-Nb-O nanotubes also promote mesenchymal stem cell adhesion and fast formation of extracellular matrix (ECM) materials. The above findings make it possible to further explore the biological properties, such as cell proliferation and drug delivery, of a variety of Ti-alloy-based oxide nanotubes. PMID:19581696

  16. A doxorubicin delivery system: Samarium/mesoporous bioactive glass/alginate composite microspheres.

    Science.gov (United States)

    Zhang, Ying; Wang, Xiang; Su, Yanli; Chen, Dongya; Zhong, Wenxing

    2016-10-01

    Samarium (Sm) incorporated mesoporous bioactive glasses (MBG) microspheres have been prepared using the method of alginate cross-linking with Ca(2+) ions. The in vitro bioactivities of Sm/MBG/alginate microspheres were studied by immersing in simulated body fluid (SBF) for various periods. The results indicated that the Sm/MBG/alginate microspheres have a faster apatite formation rate on the surface. To investigate their delivery properties further, doxorubicin (DOX) was selected as a model drug. The results showed that the Sm/MBG/alginate microspheres exhibit sustained DOX delivery, and their release mechanism is controlled by Fickian diffusion according the Higuchi model. In addition, the delivery of DOX from Sm/MBG/alginate microspheres can be dominated by changing the doping concentration of Sm and the values of pH microenvironment. These all revealed that this material is a promising candidate for the therapy of bone cancer. PMID:27287115

  17. Preparation of novel bioactive nano-calcium phosphate-hydrogel composites

    International Nuclear Information System (INIS)

    Nano-sized hydroxyapatite (nHA) and carbonate-substituted hydroxyapatite (nCHA) particles were incorporated into a poly-2-hydroxyethylmethacrylate/polycaprolactone (PHEMA/PCL) hydrogel at a filler content of 10 wt%. Fourier transform infrared absorption, transmission electron microscopy, x-ray diffraction and scanning electron microscopy were used to analyse the physical and chemical characteristics of the calcium phosphate fillers and resultant composites. Nano-sized calcium phosphate particles were produced with a needle-like morphology, average length of 50 nm and an aspect ratio of 3. The nanoparticles were uniformly distributed in the polymer matrix. The addition of both HA and CHA in nano-form enhanced the bioactivity and biocompatibility of the PHEMA/PCL matrix. The carbonate-substitution has allowed for improved bioactivity and biocompatibility of the resultant composite, indicating the potential of this material for use in bone tissue engineering.

  18. Investigating the addition of SiO₂-CaO-ZnO-Na₂O-TiO₂ bioactive glass to hydroxyapatite: Characterization, mechanical properties and bioactivity.

    Science.gov (United States)

    Yatongchai, Chokchai; Placek, Lana M; Curran, Declan J; Towler, Mark R; Wren, Anthony W

    2015-11-01

    Hydroxyapatite (Ca10(PO4)6(OH)2) is widely investigated as an implantable material for hard tissue restoration due to its osteoconductive properties. However, hydroxyapatite in bulk form is limited as its mechanical properties are insufficient for load-bearing orthopedic applications. Attempts have been made to improve the mechanical properties of hydroxyapatite, by incorporating ceramic fillers, but the resultant composite materials require high sintering temperatures to facilitate densification, leading to the decomposition of hydroxyapatite into tricalcium phosphate, tetra-calcium phosphate and CaO phases. One method of improving the properties of hydroxyapatite is to incorporate bioactive glass particles as a second phase. These typically have lower softening points which could possibly facilitate sintering at lower temperatures. In this work, a bioactive glass (SiO2-CaO-ZnO-Na2O-TiO2) is incorporated (10, 20 and 30 wt%) into hydroxyapatite as a reinforcing phase. X-ray diffraction confirmed that no additional phases (other than hydroxyapatite) were formed at a sintering temperature of 560 ℃ with up to 30 wt% glass addition. The addition of the glass phase increased the % crystallinity and the relative density of the composites. The biaxial flexural strength increased to 36 MPa with glass addition, and there was no significant change in hardness as a function of maturation. The pH of the incubation media increased to pH 10 or 11 through glass addition, and ion release profiles determined that Si, Na and P were released from the composites. Calcium phosphate precipitation was encouraged in simulated body fluid with the incorporation of the bioactive glass phase, and cell culture testing in MC-3T3 osteoblasts determined that the composite materials did not significantly reduce cell viability. PMID:26116020

  19. Effect of a new bioactive fibrous glassy scaffold on bone repair.

    Science.gov (United States)

    Gabbai-Armelin, P R; Souza, M T; Kido, H W; Tim, C R; Bossini, P S; Magri, A M P; Fernandes, K R; Pastor, F A C; Zanotto, E D; Parizotto, N A; Peitl, O; Renno, A C M

    2015-05-01

    Researchers have investigated several therapeutic approaches to treat non-union fractures. Among these, bioactive glasses and glass ceramics have been widely used as grafts. This class of biomaterial has the ability to integrate with living bone. Nevertheless, bioglass and bioactive materials have been used mainly as powder and blocks, compromising the filling of irregular bone defects. Considering this matter, our research group has developed a new bioactive glass composition that can originate malleable fibers, which can offer a more suitable material to be used as bone graft substitutes. Thus, the aim of this study was to assess the morphological structure (via scanning electron microscope) of these fibers upon incubation in phosphate buffered saline (PBS) after 1, 7 and 14 days and, also, evaluate the in vivo tissue response to the new biomaterial using implantation in rat tibial defects. The histopathological, immunohistochemistry and biomechanical analyzes after 15, 30 and 60 days of implantation were performed to investigate the effects of the material on bone repair. The PBS incubation indicated that the fibers of the glassy scaffold degraded over time. The histological analysis revealed a progressive degradation of the material with increasing implantation time and also its substitution by granulation tissue and woven bone. Histomorphometry showed a higher amount of newly formed bone area in the control group (CG) compared to the biomaterial group (BG) 15 days post-surgery. After 30 and 60 days, CG and BG showed a similar amount of newly formed bone. The novel biomaterial enhanced the expression of RUNX-2 and RANK-L, and also improved the mechanical properties of the tibial callus at day 15 after surgery. These results indicated a promising use of the new biomaterial for bone engineering. However, further long-term studies should be carried out to provide additional information concerning the material degradation in the later stages and the bone

  20. Effect of particle size on the in vitro bioactivity, hydrophilicity and mechanical properties of bioactive glass-reinforced polycaprolactone composites

    International Nuclear Information System (INIS)

    Polycaprolactone (PCL) composite films containing 5 wt.% bioactive glass (BG) particles of different sizes (6 μm, 250 nm, 3) and sodium calcium silicate (Na2CaSiO4) phases were formed. The introduction of submicron BG particles (250 nm) was shown to improve the bioactivity of PCL films. In contrast to BG microparticles, the submicron BG particles were distributed on the film surfaces, providing a high surface exposure to SBF with an improved nanotopography. A notable increase in the stiffness and elastic modulus of the composite was also obtained. As compared to submicron BG particles, lower bioactivity and elastic modulus were acquired for PCL/BG nanoparticles. It was also shown that in spite of high specific surface area of the nanoparticles, partial crystallization during mechanical milling and agglomeration of the nanoparticles during processing decrease the bioactivity, hydrophilicity and mechanical response of the BG-reinforced PCL composites. Highlights: → The effect of Bioglass particle size on the in vitro bioactivity of polycaprolactone/Bioglass composites was studied. → Partial crystallization of bioactive glass particles during high-energy mechanical milling was shown. → The submicron BG particles (250 nm) were shown to improve the bioactivity of PCL films. → Lower bioactivity was acquired for the nanocomposite due to agglomeration and partial crystallization. → The hydrophilicity and elastic modulus of the composites were shown to depend on the size of Bioglass particles.

  1. Bioactive rosette nanotube-hydroxyapatite nanocomposites improve osteoblast functions.

    Science.gov (United States)

    Sun, Linlin; Zhang, Lijie; Hemraz, Usha D; Fenniri, Hicham; Webster, Thomas J

    2012-09-01

    Inspired from biological systems, small synthetic organic molecules expressing the hydrogen bonding arrays of the DNA bases guanine and cytosine were prepared, and their self-assembly into rosette nanotubes (RNTs) was investigated. Due to their unique biological, physicochemical, and mechanical properties, RNTs could serve as the next generation of injectable orthopedic materials. In this study, a self-assembling module (termed twin base linkers or TBL) was synthesized, and the corresponding RNTs were used as bioactive components in composites of poly (2-hydroxyethyl methacrylate) (pHEMA) and hydroxyapatite (HA) nanoparticles (termed TBL/HA/pHEMA). The properties of these composites were characterized for solidification time, surface morphology, mechanical properties, and cytocompatibility. The experimental conditions were optimized to achieve solidification within 2-40 min, offering a range of properties for orthopedic applications. Composites with 20 wt% HA nanoparticles had a compressive strength (37.1 MPa) and an ultimate tensile stress (14.7 MPa) similar to that of a natural vertebral disc (5-30 MPa). Specifically, the TBL (0.01 mg/mL)/HA(20 wt%)/pHEMA composites improved long-term functions of osteoblasts (or bone-forming cells) in terms of collagen synthesis, alkaline phosphatase activity, and calcium deposition. Moreover, this composite inhibited fibroblast adhesion, thus decreasing the potential for undesirable fibrous tissue formation. In summary, this in vitro study provided evidence that TBL/HA/pHEMA composites are promising injectable orthopedic implant materials that warrant further mechanistic and in vivo studies. PMID:22530958

  2. NANO AND MICROSTRUCTURE EFFECTS ON THE BIOACTIVITY OF FORSTERITE POWDERS

    Directory of Open Access Journals (Sweden)

    Gorea M.

    2013-06-01

    Full Text Available Forsterite (Mg2SiO4 powder has been synthesized from talc (Mg3Si4O10(OH2 and magnesium carbonate (MgCO3 by applying solid state reactions method. The raw materials mixture has been milled for 10 hours until nano powders have been obtained. This mixture was then thermally treated at various temperatures. The synthesized material was structurally characterized by X-ray diffraction. Forsterite represented the main crystalline phase in the samples fired to 1100 and 1200°C, while at 1000°C small amounts of enstatite and periclase were still identified. The particles size and morphology were investigated by TEM, SEM and AFM, and the grain size distribution with a Counter Coulter-type laser granulometer. A ratio of 75 % of the particles in the samples fired to 1000, and respectively 1100°C were less than 25 nm, while the maximum size was 42 nm. For the samples fired at 1200°C, most of the particles (74 % were larger, about 6.8 μm, with a maximum of 70 μm. In order to evaluate its bioactivity, we have immersed the forsterite powder into simulating body fluids (SBF. Following 28 days of experiment, the FTIR spectra collected on the forsterite nanopowder contained the specific hydroxylapatite bands, while in the case of the micro powder these bands are hardly visible.

  3. Bioactivity of TiN-coated titanium implants

    Energy Technology Data Exchange (ETDEWEB)

    Piscanec, Stefano; Colombi Ciacchi, Lucio; Vesselli, Erik; Comelli, Giovanni; Sbaizero, Orfeo; Meriani, Sergio; De Vita, Alessandro

    2004-03-08

    Titanium nitride has excellent corrosion and wear resistance properties, and has been used as a hard coating material on titanium hip prostheses. Analysis of explants reveals that calcium phosphate phases grow spontaneously and stick strongly on TiN-coated hip prosthesis heads, indicating a degree of bioactivity of the implant surface which is absent in standard uncoated titanium implants. We investigate the mechanism of TiN oxidation using spectroscopic and first principles molecular dynamics techniques. We find that the deposition of Ca{sup 2+} ions - which is the first step of calcium phosphate nucleation - is favoured by TiO{sub x}N{sub y} oxynitride surface phases. This is due to the presence of mixed-valence states of the surface Ti atoms which leads to localisation of negative charge on surface oxygens, promoting the adsorption of Ca{sup 2+} ions. These results indicate that nitridation and controlled oxidation of titanium implant surfaces can promote the in vivo formation of bone-like material.

  4. Multilayer bioactive glass/zirconium titanate thin films in bone tissue engineering and regenerative dentistry

    Directory of Open Access Journals (Sweden)

    Mozafari M

    2013-04-01

    Full Text Available Masoud Mozafari,1,2 Erfan Salahinejad,1,3 Vahid Shabafrooz,1 Mostafa Yazdimamaghani,1 Daryoosh Vashaee,4 Lobat Tayebi1,5 1Helmerich Advanced Technology Research Center, School of Materials Science and Engineering, Oklahoma State University, Tulsa, OK, USA; 2Biomaterials Group, Faculty of Biomedical Engineering (Center of Excellence, Amirkabir University of Technology, Tehran, Iran; 3Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran; 4Helmerich Advanced Technology Research Center, School of Electrical and Computer Engineering, Oklahoma State University, Tulsa, OK, USA; 5School of Chemical Engineering, Oklahoma State University, Tulsa, OK, USA Abstract: Surface modification, particularly coatings deposition, is beneficial to tissue-engineering applications. In this work, bioactive glass/zirconium titanate composite thin films were prepared by a sol-gel spin-coating method. The surface features of the coatings were studied by scanning electron microscopy, atomic force microscopy, and spectroscopic reflection analyses. The results show that uniform and sound multilayer thin films were successfully prepared through the optimization of the process variables and the application of carboxymethyl cellulose as a dispersing agent. Also, it was found that the thickness and roughness of the multilayer coatings increase nonlinearly with increasing the number of the layers. This new class of nanocomposite coatings, comprising the bioactive and inert components, is expected not only to enhance bioactivity and biocompatibility, but also to protect the surface of metallic implants against wear and corrosion. Keywords: bioactive glass, zirconium titanate, spin-coating, microstructural properties, bone/dental applications, tissue engineering

  5. Biocompatibility and bioactivity of calcium silicate-based endodontic sealers in human dental pulp cells

    OpenAIRE

    Leticia Boldrin MESTIERI; GOMES-CORNÉLIO, Ana Lívia; RODRIGUES, Elisandra Márcia; SALLES, Loise Pedrosa; BOSSO-MARTELO, Roberta; Juliane Maria GUERREIRO-TANOMARU; TANOMARU-FILHO, Mário

    2015-01-01

    Mineral Trioxide Aggregate (MTA) is a calcium silicate-based material. New sealers have been developed based on calcium silicate as MTA Fillapex and MTA Plus. Objective The aim of this study was to evaluate biocompatibility and bioactivity of these two calcium silicate-based sealers in culture of human dental pulp cells (hDPCs). Material and Methods The cells were isolated from third molars extracted from a 16-year-old patient. Pulp tissue was sectioned into fragments with approximately 1 mm3...

  6. Traceability of Functional Bioactive Compounds in Fresh and Pasteurized Milk Obtained from Goats Fed with Orange Pulp

    OpenAIRE

    Maria Simona Chiş; Sevastiţa Muste; Maria Del Mar Camacho Vidal

    2015-01-01

    Traceability is the ability to identify and trace the history, distribution, location, and application of products, parts, and materials. A traceability system records and follows the trail as products, parts, and materials come from suppliers and are processed and ultimately distributed as end products (Prache et al, 2002). In this work, were studied the bioactive compounds (total vitamin C, ascorbic acid, total phenols, flavonoids, carotenoids, vitamin A and vitamin E) and antioxidant activ...

  7. Effects of composition and heat treatment on the microstructures of mica vitrocrystalline materials

    Energy Technology Data Exchange (ETDEWEB)

    Bezsmertnaya, Z.G.; Kishmishyan, A.A.; Nazarova, A.E.

    1985-03-01

    During the last decade a new mica glass-ceramic based on fluorphlogopite has been made, which is readily worked, mechanically strong, and chemically stable. (Items of this material are readily worked with steel tools on ordinary metal-working machines, and they have high mechanical strength and good shock and thermal resistance as well as elevated values for the electrical parameters.) This paper considers the microstructures of mica vitrocrystalline materials in relation to the heat-treatment conditions for glasses of various compositions. It is concluded that it is desirable to use two-stage crystallization to produce glass-ceramics based on fluorphlogopite with a given structure; and the roles of the primary and secondary stages of heat treatment in producing the optimum structure are established for mica-bearing glass-ceramics of various compositions.

  8. Avoiding mastoid cavity Problems: Mastoid obliteration using Bioactive glass

    Directory of Open Access Journals (Sweden)

    Said Shokry, Al`Sayed Hossieni Al`Sayed, Mohammed Fatehy Zidan,

    2012-04-01

    Full Text Available Background and objective: The aim of this study was to evaluate bioactive glass as an ideal material for the purpose of mastoid cavity elimination after mastoid surgery to avoid mastoid cavity problems.Materials and methods: In 20 patients diagnosed as cholesteatoma or chronic unsafe ear, we used different surgical techniques according to pathology and situation during surgical exploration, basically adhering to standard principles of eradicating disease in chronic unsafe ear. After performing the canal wall down (CWD or the canal wall up (CWU technique, mastoidectomy was followed by obliteration of mastoid cavity by particulate form Bioglass®. Cases were divided according to operative procedures, type of reconstruction and material used into 3 groups A- Canal wall up mastoidectomy followed by obliteration of mastoid cavity by particulate form Bioglass®. B- Canal wall down mastoidectomy followed by reconstruction of posterior meatal wall and obliteration of mastoid cavity by particulate form Bioglass®. C- Canal wall down mastoidectomy followed by reconstruction of posterior meatal wall by conchal cartilage and obliteration of mastoid cavity by Bioglass®.Results: Bioactiveglass paste is very effective for mastoid obliteration in the three groups with good integration to the surrounding tissues either connective tissue, bone, meninges or lateral dural sinus without any adverse reaction on the dura even with contact to Bioglass®. Infection was seen in 2 cases (10%, however was readily controlled by topical application of antibiotics daily for one week. In both cases no extrusion of the material occurred. Conclusion: The successful formation of bone with elimination of mastoid cavity problems proved that using Bioglass is appropriate for performing clinical mastoid obliteration.

  9. Bioactive Triterpenes from the Fungus Piptoporus betulinus

    Directory of Open Access Journals (Sweden)

    Zeyad Alresly

    2015-08-01

    Full Text Available Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1. In addition, ten known triterpenes, polyporenic acid A (5, polyporenic acid C (4, three derivatives of polyporenic acid A (8, 10, 11, betulinic acid (3, betulin (2, ergosterol peroxide (6, 9,11-dehydroergosterol peroxide (7, and fomefficinic acid (9, were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.

  10. Bioactive glass coatings for orthopedic metallic implants

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki; Tomsia, Antoni P.

    2003-06-30

    The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.

  11. Bioactivity and Functionality of Bonghwa Sweetfish

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Hun; Lee, Ju Woon; Choi, Jong Il; Song, Beom Seok; Yoon, Yo Han; Sung, Nak Yun; Jeong, Pil Mun

    2010-04-15

    - Smoked sweetfish had higher contents of calories, carbohydrate, protein, fat sodium, and calcium than unsmoked sweetfish - DHA and EPA which are omega-3 fatty acid and have therapeutic effects on arthritis and high blood pressure - Proteins and peptide from sweetfish had various bioactivities such as antioxidation, hypertensive, especially for antiinflammatory, and whitening effects. However no anticancer effect was observed - The proteins and peptide suppressed nitric oxide and cytokines (a-TNF, IL-6, IL-1 beta), and prostaglandin (PGE2) productions, and mRNA related iNOS and cyclooxygenase (COX-2), which are related to inflammation - The proteins and peptide prevented tyrosinase formation, which is related formation of melanin, and also showed preventive effects of melanin synthesis, antioxidation and anti-aging effects. Thus, the proteins and peptides from sweetfish may be useful source for cosmetics

  12. Bioactive Compounds Found in Brazilian Cerrado Fruits

    Directory of Open Access Journals (Sweden)

    Elisa Flávia Luiz Cardoso Bailão

    2015-10-01

    Full Text Available Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi, Dipteryx alata Vog. (baru, Eugenia dysenterica DC. (cagaita, Eugenia uniflora L. (pitanga, Genipa americana L. (jenipapo, Hancornia speciosa Gomes (mangaba, Mauritia flexuosa L.f. (buriti, Myrciaria cauliflora (DC Berg (jabuticaba, Psidium guajava L. (goiaba, Psidium spp. (araçá, Solanum lycocarpum St. Hill (lobeira, Spondias mombin L. (cajá, Annona crassiflora Mart. (araticum, among others are reported here.

  13. Bioactive properties of honey with propolis.

    Science.gov (United States)

    Osés, S M; Pascual-Maté, A; Fernández-Muiño, M A; López-Díaz, T M; Sancho, M T

    2016-04-01

    Nowadays, propolis is used as an innovative preservative and as a bioactive food supplement. Due to its bitter and astringent flavour, propolis is hardly accepted by consumers. The aim of this study was to obtain a likeable food product made with honey and propolis, whose antimicrobial, antioxidant and anti-inflammatory properties were enhanced in comparison with those of the base honeys used. 0.1%, 0.3% and 0.5% soft propolis extracts were added to honeys and the products that most appealed to the users were subjected to further research. Total phenolics, flavonoids, ABTS free radical and hydroxyl radicals scavenging and anti-inflammatory activities increased in all mixtures. Antimicrobial activity of the combined products showed synergic effects, resulting in higher results than those of the base honeys and propolis extracts. Therefore, honeys enriched with small amounts of propolis extracts are promising functional foods. PMID:26593609

  14. Bioactivity and Functionality of Bonghwa Sweetfish

    International Nuclear Information System (INIS)

    - Smoked sweetfish had higher contents of calories, carbohydrate, protein, fat sodium, and calcium than unsmoked sweetfish - DHA and EPA which are omega-3 fatty acid and have therapeutic effects on arthritis and high blood pressure - Proteins and peptide from sweetfish had various bioactivities such as antioxidation, hypertensive, especially for antiinflammatory, and whitening effects. However no anticancer effect was observed - The proteins and peptide suppressed nitric oxide and cytokines (a-TNF, IL-6, IL-1 beta), and prostaglandin (PGE2) productions, and mRNA related iNOS and cyclooxygenase (COX-2), which are related to inflammation - The proteins and peptide prevented tyrosinase formation, which is related formation of melanin, and also showed preventive effects of melanin synthesis, antioxidation and anti-aging effects. Thus, the proteins and peptides from sweetfish may be useful source for cosmetics

  15. Bioactive Compounds Found in Brazilian Cerrado Fruits.

    Science.gov (United States)

    Bailão, Elisa Flávia Luiz Cardoso; Devilla, Ivano Alessandro; da Conceição, Edemilson Cardoso; Borges, Leonardo Luiz

    2015-01-01

    Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidium guajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here. PMID:26473827

  16. Bioactive Metabolites from Spilanthes acmella Murr.

    Directory of Open Access Journals (Sweden)

    Virapong Prachayasittikul

    2009-02-01

    Full Text Available Spilanthes acmella Murr. (Compositae has been used as a traditional medicine for toothache, rheumatism and fever. Its extracts had been shown to exhibit vasorelaxant and antioxidant activities. Herein, its antimicrobial, antioxidant and cytotoxic activities were evaluated. Agar dilution method assays against 27 strains of microorganisms were performed. Results showed that fractions from the chloroform and methanol extracts inhibited the growth of many tested organisms, e.g. Corynebacterium diphtheriae NCTC 10356 with minimum inhibitory concentration (MIC of 64-256 mg/mL and Bacillus subtilis ATCC 6633 with MIC of 128-256 mg/mL. The tested fractions all exhibited antioxidant properties in both DPPH and SOD assays. Potent radical scavenging activity was observed in the DPPH assay. No cytotoxic effects of the extracts against KB and HuCCA-1 cell lines were evident. Bioassay-guided isolation resulted in a diverse group of bioactive compounds such as phenolics [vanillic acid (2, trans-ferulic acid (5 and trans-isoferulic acid (6], coumarin (scopoletin, 4 and triterpenoids like 3-acetylaleuritolic acid (1, b-sitostenone (3, stigmasterol and stigmasteryl-3-O-b-D-glucopyranosides, in addition to a mixture of stigmasteryl-and b-sitosteryl-3-O-b-D-glucopyranosides. The compounds 1–6 represent bioactive metabolites of S. acmella Murr. that were never previously reported. Our findings demonstrate for the first time the potential benefits of this medicinal plant as a rich source of high therapeutic value compounds for medicines, cosmetics, supplements and as a health food.

  17. Bioactive Labels for Fresh Fruits and Vegetables

    Directory of Open Access Journals (Sweden)

    Nasui Liana

    2013-11-01

    Full Text Available Pesticide residues and microbial load on the surface of fresh fruits and vegetables becomes a major concern due to the safety and quality of these products for consumer.In order to minimize these risk factors (pesticide residues and microbial load, were achieved labels for fruits and vegetables that are consumed with shell which disintegrates under the influence of water jet and thus reduce the amount of these contaminants. Were elaborated labels based on polymer (chitosan at a concentration of 2%, which incorporate bioactive compounds from green tea with potential decontaminant of the peel of this products. Green tea extract was obtained by infusing 1 g of dried green tea in 100 ml water at 80° C for 10 minutes. The extract was filtered and then mixed with 2 g chitosan acidified with 0.7% glacial acetic acid and dilute to the mark with distilled water. Were identified bioactive compounds from green tea, using UV-VIS and HPLC. Then were elaborated the labels. These tags were used on pepper, tomato, apple and  nectarine. Were quantified the microbial load and the pesticide residues on their surface unwashed, washed only with water and were monitored the influence of labels on these factors. Identified pesticides were mefenoxan and thiamethoxam, which were quantified by HPLC. In what it concerns the influence, were founded the absence of germs at pepper and a significant decrease at the other. In terms of  the potential of reducing pesticide, the experimental results have indicated that the label can prove its effectiveness.  

  18. Bioactive Labels for Fresh Fruits and Vegetables

    Directory of Open Access Journals (Sweden)

    Liana Nasui

    2013-11-01

    Full Text Available Pesticide residues and microbial load on the surface of fresh fruits and vegetables becomes a major concern due to the safety and quality of these products for consumer.In order to minimize these risk factors (pesticide residues and microbial load, were achieved labels for fruits and vegetables that are consumed with shell which disintegrates under the influence of water jet and thus reduce the amount of these contaminants. Were elaborated labels based on polymer (chitosan at a concentration of 2%, which incorporate bioactive compounds from green tea with potential decontaminant of the peel of this products. Green tea extract was obtained by infusing 1 g of dried green tea in 100 ml water at 80° C for 10 minutes. The extract was filtered and then mixed with 2 g chitosan acidified with 0.7% glacial acetic acid and dilute to the mark with distilled water. Were identified bioactive compounds from green tea, using UV-VIS and HPLC. Then were elaborated the labels. These tags were used on pepper, tomato, apple and  nectarine. Were quantified the microbial load and the pesticide residues on their surface unwashed, washed only with water and were monitored the influence of labels on these factors. Identified pesticides were mefenoxan and thiamethoxam, which were quantified by HPLC. In what it concerns the influence, were founded the absence of germs at pepper and a significant decrease at the other. In terms of  the potential of reducing pesticide, the experimental results have indicated that the label can prove its effectiveness.

  19. Vesicular system: Versatile carrier for transdermal delivery of bioactives.

    Science.gov (United States)

    Singh, Deependra; Pradhan, Madhulika; Nag, Mukesh; Singh, Manju Rawat

    2015-01-01

    The transdermal route of drug delivery has gained immense interest for pharmaceutical researchers. The major hurdle for diffusion of drugs and bioactives through transdermal route is the stratum corneum, the outermost layer of the skin. Currently, various approaches such as physical approach, chemical approach, and delivery carriers have been used to augment the transdermal delivery of bioactives. This review provides a brief overview of mechanism of drug transport across skin, different lipid vesicular systems, with special emphasis on lipid vesicular systems including transfersomes, liposomes, niosomes, ethosomes, virosomes, and pharmacosomes and their application for the delivery of different bioactives. PMID:24564350

  20. Nutrient reference values for bioactives: new approaches needed?

    DEFF Research Database (Denmark)

    Biesalski, Hans Konrad; Erdman Jr., John W.; Hathcock, John;

    2013-01-01

    Nutrients can be classified as either "essential" or "non-essential," the latter are also termed bioactive substances. Whereas the absence of essential nutrients from the diet results in overt deficiency often times with moderate to severe physiological decrements, the absence of bioactive substa...... ingredient. This conference explores the definitions, concepts, and data on two of the best examples of bioactive substances that, perhaps, should have NRVs: lutein and zeaxanthin, and n-3 long-chain polyunsaturated fatty acids. © 2013 The Author(s)....

  1. Development and clinical trial of a novel bioactive bone cement

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Strontium(Sr)and related compounds have become more attractive in the prevention and treatment of osteoporosis.Previously,we developed a novel bioactive bone cement which is mainly composed of strontium-containing hydroxyapatite(Sr-HA)filler and bisphenol A diglycidylether dimethacrylate(Bis-GMA)resin.This bone cement is superior to conventional polymethylmethacrylate (PMMA)bone cement in bioactivity,biocompatibility,and osseointegration.It also has shown sufficient mechanical strength properties for its use in percutaneous vertebroplasty(PVP)and total hip replacement(THR).In this paper,we review the in vitro,in vivo and clinical evidence for the effectiveness of this bioactive bone cement.

  2. TRENDS ON ANALYTICAL METHODS FOR RESVERATROL, A MAJOR BIOACTIVE

    OpenAIRE

    Cabrita, Maria João; Martins, Nuno; Soares, Bruno; Costa Freitas, Ana Maria; Garcia, Raquel

    2014-01-01

    Resveratrol (3,5,4-trans-trihydroxystilbene) is a member of the stilbene group of phenolic compounds, comprising two aromatic rings linked by an ethylene bridge and is considered one of the most promising bioactive compounds due to its bioactivity. Wine is one of the main source of this bioactive compound in Mediterranean diet. Several authors have dedicated their research to the relationship between diet and health, and concerning wine and health studies, ‘‘French Paradox’’ was the starting ...

  3. Effect of sintering temperature variations on fabrication of 45S5 bioactive glass-ceramics using rice husk as a source for silica.

    Science.gov (United States)

    Leenakul, Wilaiwan; Tunkasiri, Tawee; Tongsiri, Natee; Pengpat, Kamonpan; Ruangsuriya, Jetsada

    2016-04-01

    45S5 bioactive glass is a highly bioactive substance that has the ability to promote stem cell differentiation into osteoblasts--the cells that create bone matrix. The aim of this work is to analyze physical and mechanical properties of 45S5 bioactive glass fabricated by using rice husk ash as its silica source. The 45S5 bioactive glass was prepared by melting the batch at 1300 °C for 3h. The samples were sintered at different temperatures ranging from 900 to 1050 °C with a fixed dwell-time of 2h. The phase transitions, density, porosity and microhardness values were investigated and reported. DTA analysis was used to examine the crystallization temperatures of the glasses prepared. We found that the sintering temperature had a significant effect on the mechanical and physical properties of the bioactive glass. The XRD showed that when the sintering temperature was above 650 °C, crystallization occurred and bioactive glass-ceramics with Na2Ca2Si3O9, Na2Ca4(PO4)2SiO4 and Ca3Si2O7 were formed. The optimum sintering temperature resulting in maximum mechanical values was around 1050 °C, with a high density of 2.27 g/cm(3), 16.96% porosity and the vicker microhardness value of 364HV. Additionally, in vitro assay was used to examine biological activities in stimulated body fluid (SBF). After incubation in SBF for 7 days, all of the samples showed formations of apatite layers indicating that the 45S5 bioactive glasses using rice husk as a raw material were also bioactive. PMID:26838899

  4. Effects of orange winemaking variables on antioxidant activity and bioactive compounds

    Directory of Open Access Journals (Sweden)

    María del Carmen Schvab

    2015-09-01

    Full Text Available AbstractAscorbic acid, carotenoids and polyphenols stand out among the orange juice natural antioxidants. The winemaking process affects their bioavailability and bioactivity. Antioxidant activities (AA were estimated in different process conditions to asses those properties. The AA and their correlation with ascorbic acid, total phenolics and carotenoids content were calculated. The variables and levels analyzed were: pasteurized and natural must (PJ and NJ, pH 3.5 and 4.0 and fermentation temperatures at 10°C and 20°C. Statistically significant differences (α=0.05 were found among bioactive compounds concentrations. Antioxidant compounds concentration was higher in raw material than in orange wine. Juice pasteurization caused the major losses while subsequent vinification affects them to a lesser extent. Highest antioxidants retention was measured in wines from JN fermented at pH 3.5 and 10 °C (JN-3.5-10 followed by wines from JP and fermented at the same conditions (JP-3.5-10. AA determined by DPPH showed a positive and close correlation with FRAP, while ABTS showed a low correlation with former assays. Juice pasteurization process and fermentation temperature influenced bioactive compound reduction which correlates with the AA variation.

  5. Corrosion mechanism and bioactivity of borate glasses analogue to Hench’s bioglass

    Directory of Open Access Journals (Sweden)

    Mona A. Ouis

    2012-09-01

    Full Text Available Bioactive borate glasses (from the system Na2O-CaO-B2O3-P2O5 and corresponding glass-ceramics as a new class of scaffold material were prepared by full replacement of SiO2 with B2O3 in Hench patented bioactive glass. The prepared samples were investigated by differential thermal analysis (DTA, Fourier transform infrared (FTIR spectroscopy and X-ray diffraction (XRD analysis. The DTA data were used to find out the proper heat treatment temperatures for preparation of the appropriate glass-ceramics with high crystallinity. The prepared crystalline glass-ceramics derivatives were examined by XRD to identify the crystalline phases that were precipitated during controlled thermal treatment. The FTIR spectroscopy was used to justify the formation of hydroxyapatite as an indication of the bioactivity potential or activity of the studied ternary borate glasses or corresponding glass-ceramics after immersion in aqueous phosphate solution. The corrosion results are interpreted on the basis of suggested recent views on the corrosion mechanism of such modified borate glasses in relation to their composition and constitution.

  6. Mixed zirconia calcium phosphate coatings for dental implants: Tailoring coating stability and bioactivity potential

    International Nuclear Information System (INIS)

    Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants. - Highlights: • Different ratios of zirconia (TZ) and calcium phosphate (CP) were deposited on zirconia substrates. • Enhancement of TZ content in mixed coatings increased coating stability. • Enhancement of CP content in mixed coatings increased bioactivity. • All tested coating compositions were non-toxic

  7. In Vitro Evaluation of Bioactivity of Chemically Deposited Hydroxyapatite on Polyether Ether Ketone

    Directory of Open Access Journals (Sweden)

    D. Almasi

    2015-01-01

    Full Text Available Polyether ether ketone (PEEK is considered the best alternative material for titanium for spinal fusion cage implants due to its low elasticity modulus and radiolucent property. The main problem of PEEK is its bioinert properties. Coating with hydroxyapatite (HA showed very good improvement in bioactivity of the PEEK implants. However the existing methods for deposition of HA have some disadvantages and damage the PEEK substrate. In our previous study a new method for deposition of HA on PEEK was presented. In this study cell proliferation of mesenchymal stem cell and apatite formation in simulated body fluid (SBF tests were conducted to probe the effect of this new method in improvement of the bioactivity of PEEK. The mesenchymal stem cell proliferation result showed better cells proliferation on the treated layer in comparison with untreated PEEK. The apatite formation results showed the growth of the HA on the treated PEEK but there was not any sight of the growth of HA on the untreated PEEK even after 2 weeks. The results showed the new method of the HA deposition improved the bioactivity of the treated PEEK in comparison with the bare PEEK.

  8. Divalent ion encapsulated nano titania on Ti metal as a bioactive surface with enhanced protein adsorption.

    Science.gov (United States)

    Anbazhagan, Esaitamil; Rajendran, Archana; Natarajan, Duraipandy; Kiran, M S; Pattanayak, Deepak K

    2016-07-01

    A novel approach on incorporation of divalent species such as Mg, Ca and Sr into the titania nanostructures formed on Ti metal surface and their comparative study on enhancement of bioactivity, protein adsorption and cell compatibility is reported. When treated with hydrogen peroxide, Ti metal forms hydrogen titanate. On subsequent treatment with Mg or Ca or Sr nitrate solutions, respective ions are incorporated into hydrogen titanate layer, and heat treatment leads to titania decorated with these ions. The resultant heat-treated samples when soaked in simulated body fluid form bone-like apatite which indicates the present surface modification enhances the bioactivity. Further, enhanced protein adsorption in bovine serum albumin is an indication of suitability of these divalent species to form chelate compounds with amino acids, and Ca containing titania nanostructure favours more protein adsorption compared to the others. Cytocompatibility studies using MG-63, human osteosarcoma cell lines shows these divalent ion containing titania nanostructure favours the cell attachment and did not show any cytotoxicity. Bioactivity, enhanced protein adsorption along with cytocompatibility clearly indicates such surface modification approach to be useful to design hard tissue replacement materials in orthopaedic and dental field. PMID:27011351

  9. Mixed zirconia calcium phosphate coatings for dental implants: Tailoring coating stability and bioactivity potential

    Energy Technology Data Exchange (ETDEWEB)

    Pardun, Karoline [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Treccani, Laura, E-mail: treccani@uni-bremen.de [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Volkmann, Eike [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany); Streckbein, Philipp [University Hospital, Justus-Liebig-University Giessen, Department of Cranio-Maxillo-Facial Surgery, Klinikstrasse 33, 35385 Giessen (Germany); Heiss, Christian [University Hospital of Giessen-Marburg, Department of Trauma Surgery, Rudolf-Buchheim-Strasse 7, 35385 Giessen, Germany, (Germany); Laboratory of Experimental Surgery, Kerkraderstrasse 9, 35392 Giessen (Germany); Destri, Giovanni Li; Marletta, Giovanni [Laboratory for Molecular Surfaces and Nanotechnology (LAMSUN), Department of Chemistry, University of Catania and CSGI, Viale A. Doria 6, 95125 Catania (Italy); Rezwan, Kurosch [University of Bremen, Advanced Ceramics, Am Biologischen Garten 2, 28359 Bremen (Germany)

    2015-03-01

    Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants. - Highlights: • Different ratios of zirconia (TZ) and calcium phosphate (CP) were deposited on zirconia substrates. • Enhancement of TZ content in mixed coatings increased coating stability. • Enhancement of CP content in mixed coatings increased bioactivity. • All tested coating compositions were non-toxic.

  10. Bioactive proteins against pathogenic and spoilage bacteria

    Directory of Open Access Journals (Sweden)

    Mahmoud Z. Sitohy

    2014-10-01

    Full Text Available Background: It is likely that both human nutrition and the nutrition of livestock are benefited by the presence of bioactive proteins within their respective diet regimes. Bioactive proteins have been defined as specific protein fragments that positively impact bodily functions or conditions and may, ultimately, influence overall human health. The ingestion of bioactive proteins may have an effect on the major body systems—namely, the cardiovascular, digestive, immune and nervous systems. According to their functional properties, bioactive proteins may be classified as antimicrobial, antithrombotic, antihypertensive, opioid, immune-modulatory, mineral binding and anti-oxidative. There are many examples of biologically active food proteins and active peptides that can be obtained from various food protein sources. They have a physiological significance beyond the pure nutritional requirements; in other wordsthey have the acquisition of nitrogen for normal growth and maintenance. Objective: This study aims to specify and characterize the extent and mode of action of bioactive proteins in their native form, (glycinin, glycinin basic sub-unit and β-conglycinin against specific main pathogens (Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica serovar Enteritidis. We will be using standard media while identifying the main constituents responsible for this action. Methods: Glycinin, basic sub-unit and β-conglycinin were isolated from soybean protein and tested for their antimicrobial action against pathogenic and spoilage bacteria, They were thencompared to the properties of penicillin. Methylated soybean protein and also methylated chickpea protein (MSP and MCP, with isoelectric points around pI 8, were prepared by esterifying. 83 % of their free carboxyl groups and their interactions with Gram positive and Gram negative bacteria were examined. Results: The three divisions of cationic proteins exhibited antibacterial

  11. In vitro study of improved wound-healing effect of bioactive borate-based glass nano-/micro-fibers

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qingbo [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering (CBSE), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell and Single Molecule Monitoring (CS3M), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Chen, Sisi [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering (CBSE), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Shi, Honglan [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering (CBSE), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell and Single Molecule Monitoring (CS3M), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Xiao, Hai [Department of Electrical and Computer Engineering, Clemson University, Clemson, SC 29634 (United States); Ma, Yinfa, E-mail: yinfa@mst.edu [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering (CBSE), Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell and Single Molecule Monitoring (CS3M), Missouri University of Science and Technology, Rolla, MO 65409 (United States)

    2015-10-01

    Because of the promising wound-healing capability, bioactive glasses have been considered as one of the next generation hard- and soft-tissue regeneration materials. The lack of understanding of the substantial mechanisms, however, indicates the need for further study on cell–glass interactions to better interpret the rehabilitation capability. In the present work, three bioactive glass nano-/micro-fibers, silicate-based 45S5, borate-based 13-93B3 and 1605 (additionally doped with copper oxide and zinc oxide), were firstly compared for their in vitro soaking/conversion rate. The results of elemental monitoring and electron microscopic characterization demonstrated that quicker ion releasing and glass conversion occurred in borate-based fibers than that of silicate-based one. This result was also reflected by the formation speed of hydroxyapatite (HA). This process was further correlated with original boron content and surrounding rheological condition. We showed that an optimal fiber pre-soaking time (or an ideal dynamic flow rate) should exist to stimulate the best cell proliferation and migration ability. Moreover, 13-93B3 and 1605 fibers showed different glass conversion and biocompatibility properties as well, indicating that trace amount variation in composition can also influence fiber's bioactivity. In sum, our in vitro rheological module closely simulated in vivo niche environment and proved a potentially improved wound-healing effect by borate-based glass fibers, and the results shall cast light on future improvement in bioactive glass fabrication. - Highlights: • Bioactive glass nano-/micro-materials were effectively used for tissue wound healing. • The wound-healing effects of silicate-based 45S5, borate-based 13-93B3 and 1605 fibers were investigated. • Glass conversion rates were compared under either static or dynamic-flow modes. • Glass compositions and flow rates greatly influenced bioactivity and cell migration. • These results can

  12. In vitro study of improved wound-healing effect of bioactive borate-based glass nano-/micro-fibers

    International Nuclear Information System (INIS)

    Because of the promising wound-healing capability, bioactive glasses have been considered as one of the next generation hard- and soft-tissue regeneration materials. The lack of understanding of the substantial mechanisms, however, indicates the need for further study on cell–glass interactions to better interpret the rehabilitation capability. In the present work, three bioactive glass nano-/micro-fibers, silicate-based 45S5, borate-based 13-93B3 and 1605 (additionally doped with copper oxide and zinc oxide), were firstly compared for their in vitro soaking/conversion rate. The results of elemental monitoring and electron microscopic characterization demonstrated that quicker ion releasing and glass conversion occurred in borate-based fibers than that of silicate-based one. This result was also reflected by the formation speed of hydroxyapatite (HA). This process was further correlated with original boron content and surrounding rheological condition. We showed that an optimal fiber pre-soaking time (or an ideal dynamic flow rate) should exist to stimulate the best cell proliferation and migration ability. Moreover, 13-93B3 and 1605 fibers showed different glass conversion and biocompatibility properties as well, indicating that trace amount variation in composition can also influence fiber's bioactivity. In sum, our in vitro rheological module closely simulated in vivo niche environment and proved a potentially improved wound-healing effect by borate-based glass fibers, and the results shall cast light on future improvement in bioactive glass fabrication. - Highlights: • Bioactive glass nano-/micro-materials were effectively used for tissue wound healing. • The wound-healing effects of silicate-based 45S5, borate-based 13-93B3 and 1605 fibers were investigated. • Glass conversion rates were compared under either static or dynamic-flow modes. • Glass compositions and flow rates greatly influenced bioactivity and cell migration. • These results can

  13. Nanoengineering of bioactive glasses: hollow and dense nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Luz, Gisela M., E-mail: gisela.luz@dep.uminho.pt; Mano, Joao F., E-mail: jmano@dep.uminho.pt [University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, 3B' s Research Group, Biomaterials, Biodegradables and Biomimetics (Portugal)

    2013-02-15

    The possibility of engineering bioactive glass (BG) nanoparticles into suitable sizes and shapes represents a significant achievement regarding the development of new osteoconductive biomaterials for therapeutic strategies to replace or regenerate damaged mineralised tissues. Herein we report the structural and chemical evolution of sol-gel derived BG nanoparticles for both the binary (SiO{sub 2}:CaO (mol%) = 70:30) and ternary (SiO{sub 2}:CaO:P{sub 2}O{sub 5} (mol%) = 55:40:5) formulations, in order to understand how the particles formation can be directed. Hollow BG nanospheres were obtained through Ostwald ripening. The presence of a non ionic surfactant, poly(ethylene glycol) (PEG), allowed the formation of dense BG nanospheres with controllable diameters depending on the molecular weight of PEG. A deep insight into the genesis of BG nanoparticles formation is essential to design BG based materials with controlled compositions, morphologies and sizes at the nanoscale, in order to improve their performance in orthopaedic applications including bone tissue engineering.

  14. Nanoengineering of bioactive glasses: hollow and dense nanospheres

    International Nuclear Information System (INIS)

    The possibility of engineering bioactive glass (BG) nanoparticles into suitable sizes and shapes represents a significant achievement regarding the development of new osteoconductive biomaterials for therapeutic strategies to replace or regenerate damaged mineralised tissues. Herein we report the structural and chemical evolution of sol–gel derived BG nanoparticles for both the binary (SiO2:CaO (mol%) = 70:30) and ternary (SiO2:CaO:P2O5 (mol%) = 55:40:5) formulations, in order to understand how the particles formation can be directed. Hollow BG nanospheres were obtained through Ostwald ripening. The presence of a non ionic surfactant, poly(ethylene glycol) (PEG), allowed the formation of dense BG nanospheres with controllable diameters depending on the molecular weight of PEG. A deep insight into the genesis of BG nanoparticles formation is essential to design BG based materials with controlled compositions, morphologies and sizes at the nanoscale, in order to improve their performance in orthopaedic applications including bone tissue engineering.

  15. Improved bonding strength of bioactive cermet Cold Gas Spray coatings.

    Science.gov (United States)

    Gardon, M; Concustell, A; Dosta, S; Cinca, N; Cano, I G; Guilemany, J M

    2014-12-01

    The fabrication of cermet biocompatible coatings by means Cold Gas Spray (CGS) provides prosthesis with outstanding mechanical properties and the required composition for enhancing the bioactivity of prosthetic materials. In this study, hydroxyapatite/Titanium coatings were deposited by means of CGS technology onto titanium alloy substrates with the aim of building-up well-bonded homogeneous coatings. Powders were blended in different percentages and sprayed; as long as the amount of hydroxyapatite in the feedstock increased, the quality of the coating was reduced. Besides, the relation between the particle size distribution of ceramic and metallic particles is of significant consideration. Plastic deformation of titanium particles at the impact eased the anchoring of hard hydroxyapatite particles present at the top surface of the coating, which assures the looked-for interaction with the cells. Coatings were immersed in Hank's solution for 1, 4 and 7 days; bonding strength value was above 60 MPa even after 7 days, which enhances common results of HAp coatings obtained by conventional thermal spray technologies. PMID:25491809

  16. History and trends of bioactive glass-ceramics.

    Science.gov (United States)

    Montazerian, Maziar; Dutra Zanotto, Edgar

    2016-05-01

    The interest around bioactive glass-ceramics (GCs) has grown significantly over the last two decades due to their appropriate biochemical and mechanical properties. The intense research effort in this field has led to some new commercial products for biomedical applications. This review article begins with the basic concepts of GC processing and development via controlled heat treatments of monolithic pieces or sinter-crystallization of powdered glasses. We then go on to describe the processing, properties, and applications of some commercial bioactive GCs and discuss selected valuable reported researches on several promising types of bioactive GCs. The article finishes with a section on open relevant research directions for bioactive GC development. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1231-1249, 2016. PMID:26707951

  17. Role of bioactive fatty acids in nonalcoholic fatty liver disease.

    Science.gov (United States)

    Juárez-Hernández, Eva; Chávez-Tapia, Norberto C; Uribe, Misael; Barbero-Becerra, Varenka J

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD) is characterized by fat deposition in hepatocytes, and a strong association with nutritional factors. Dietary fatty acids are classified according to their biochemical properties, which confer their bioactive roles. Monounsaturated fatty acids have a dual role in various human and murine models. In contrast, polyunsaturated fatty acids exhibit antiobesity, anti steatosic and anti-inflammatory effects. The combination of these forms of fatty acids-according to dietary type, daily intake and the proportion of n-6 to n-3 fats-can compromise hepatic lipid metabolism. A chemosensory rather than a nutritional role makes bioactive fatty acids possible biomarkers for NAFLD. Bioactive fatty acids provide health benefits through modification of fatty acid composition and modulating the activity of liver cells during liver fibrosis. More and better evidence is necessary to elucidate the role of bioactive fatty acids in nutritional and clinical treatment strategies for patients with NAFLD. PMID:27485440

  18. Gel-derived SiO{sub 2}-CaO-Na{sub 2}O-P{sub 2}O{sub 5} bioactive powders: Synthesis and in vitro bioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Renato Luiz, E-mail: rastosfix@gmail.com; Peitl, Oscar; Dutra Zanotto, Edgar

    2011-07-20

    In the present work, bioactive powders of the quaternary SiO{sub 2}-CaO-Na{sub 2}O-P{sub 2}O{sub 5} system were synthesized by means of a sol-gel route. In their synthesis, tetraethoxysilane (Si(OC{sub 2}H{sub 5}){sub 4}), calcium nitrate tetrahydrate (Ca(NO{sub 3}){sub 2}{center_dot} 4H{sub 2}O) and sodium nitrate (NaNO{sub 3}) were chosen as precursors of SiO{sub 2}, CaO and Na{sub 2}O, respectively. For P{sub 2}O{sub 5}, two different precursors were tested: triethylphosphate (OP(OC{sub 2}H{sub 5}){sub 3}) and phosphoric acid (H{sub 3}PO{sub 4}). The gels were then converted into ceramic powders by heat treatments in the temperature range 700-1000 deg. C. The resulting materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS) and in vitro bioactivity in acellular simulated body fluid (SBF). During the conversion of the gels into ceramics the mineralization behavior of the two sets of samples was different, but all the resulting materials were bioactive. The samples prepared using phosphoric acid exhibited the best in vitro bioactivity. This result was attributed to the preferential formation of bioactive sodium calcium silicate Na{sub 2}Ca{sub 2}Si{sub 3}O{sub 9} crystals, especially in the samples submitted to heat treatments at 700 and 800 deg. C, which could not be observed in the samples prepared using triethylphosphate.

  19. Incorporation of sol-gel bioactive glass into PLGA improves mechanical properties and bioactivity of composite scaffolds and results in their osteoinductive properties.

    Science.gov (United States)

    Filipowska, J; Pawlik, J; Cholewa-Kowalska, K; Tylko, G; Pamula, E; Niedzwiedzki, L; Szuta, M; Laczka, M; Osyczka, A M

    2014-12-01

    In this study, 3D porous bioactive composite scaffolds were produced and evaluated for their physico-chemical and biological properties. Polymer poly-L-lactide-co-glycolide (PLGA) matrix scaffolds were modified with sol-gel-derived bioactive glasses (SBGs) of CaO-SiO2-P2O5 systems. We hypothesized that SBG incorporation into PLGA matrix would improve the chemical and biological activity of composite materials as well as their mechanical properties. We applied two bioactive glasses, designated as S2 or A2, differing in the content of SiO2 and CaO (i.e. 80 mol% SiO2, 16 mol% CaO for S2 and 40 mol% SiO2, 52 mol% CaO for A2). The composites were characterized for their porosity, bioactivity, microstructure and mechanical properties. The osteoinductive properties of these composites were evaluated in human bone marrow stromal cell (hBMSC) cultures grown in either standard growth medium or treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) or dexamethasone (Dex). After incubation in simulated body fluid, calcium phosphate precipitates formed inside the pores of both A2-PLGA and S2-PLGA scaffolds. The compressive strength of the latter was increased slightly compared to PLGA. Both composites promoted superior hBMSC attachment to the material surface and stimulated the expression of several osteogenic markers in hBMSC compared to cells grown on unmodified PLGA. There were also marked differences in the response of hBMSC to composite scaffolds, depending on chemical compositions of the scaffolds and culture treatments. Compared to silica-rich S2-PLGA, hBMSC grown on calcium-rich A2-PLGA were overall less responsive to rhBMP-2 or Dex and the osteoinductive properties of these A2-PLGA scaffolds seemed partially dependent on their ability to induce BMP signaling in untreated hBMSC. Thus, beyond the ability of currently studied composites to enhance hBMSC osteogenesis, it may become possible to modulate the osteogenic response of hBMSC, depending on the

  20. Incorporation of sol–gel bioactive glass into PLGA improves mechanical properties and bioactivity of composite scaffolds and results in their osteoinductive properties

    International Nuclear Information System (INIS)

    In this study, 3D porous bioactive composite scaffolds were produced and evaluated for their physico-chemical and biological properties. Polymer poly-L-lactide-co-glycolide (PLGA) matrix scaffolds were modified with sol–gel-derived bioactive glasses (SBGs) of CaO–SiO2–P2O5 systems. We hypothesized that SBG incorporation into PLGA matrix would improve the chemical and biological activity of composite materials as well as their mechanical properties. We applied two bioactive glasses, designated as S2 or A2, differing in the content of SiO2 and CaO (i.e. 80 mol% SiO2, 16 mol% CaO for S2 and 40 mol% SiO2, 52 mol% CaO for A2). The composites were characterized for their porosity, bioactivity, microstructure and mechanical properties. The osteoinductive properties of these composites were evaluated in human bone marrow stromal cell (hBMSC) cultures grown in either standard growth medium or treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) or dexamethasone (Dex). After incubation in simulated body fluid, calcium phosphate precipitates formed inside the pores of both A2-PLGA and S2-PLGA scaffolds. The compressive strength of the latter was increased slightly compared to PLGA. Both composites promoted superior hBMSC attachment to the material surface and stimulated the expression of several osteogenic markers in hBMSC compared to cells grown on unmodified PLGA. There were also marked differences in the response of hBMSC to composite scaffolds, depending on chemical compositions of the scaffolds and culture treatments. Compared to silica-rich S2-PLGA, hBMSC grown on calcium-rich A2-PLGA were overall less responsive to rhBMP-2 or Dex and the osteoinductive properties of these A2-PLGA scaffolds seemed partially dependent on their ability to induce BMP signaling in untreated hBMSC. Thus, beyond the ability of currently studied composites to enhance hBMSC osteogenesis, it may become possible to modulate the osteogenic response of h

  1. Porous bioactive glass and glass-ceramics made by reaction sintering under pressure.

    Science.gov (United States)

    Gong, W; Abdelouas, A; Lutze, W

    2001-03-01

    A glass and a rhenanite-wollastonite glass-ceramic were synthesized with the qualitative composition Na2O-CaO-SiO2-P2O5. Both materials were prepared by reaction sintering under isostatic pressure (RSIP) using powder mixtures. Solid state reactions were complete within a few hours at 950 degrees C under modest pressure. Formation of the glass and crystalline phases was driven by an intermediate, reactive, low viscosity Na2O-SiO2 phase. A reaction mechanism is suggested. Porous materials were obtained with two ranges of pore sizes: 100-200 microm and ceramic were corroded in simulated body fluid at 37 degrees C. The evolution of surface features was studied. Gel layers formed on both materials. Corrosion was fastest inside the pores. Microcrystals of apatite were identified by crystal structure analysis and by chemical analysis. During corrosion of the glass-ceramic, rhenanite most likely was converted into apatite. Comparison of these results with published information suggests that the glass and glass-ceramic are bioactive. We suggest that RSIP can be used (a) to control the surface porosity and pore size of bioactive implants, thereby increasing the stability of tissue/implant interfaces; (b) to make glasses and glass-ceramics with new properties; and (c) to make near net-shape materials. PMID:11189036

  2. Enzymatic induction of supramolecular order and bioactivity

    Science.gov (United States)

    Yang, Chengbiao; Ren, Xinrui; Ding, Dan; Wang, Ling; Yang, Zhimou

    2016-05-01

    We showed in this study that enzymatic triggering is a totally different pathway for the preparation of self-assembling nanomaterials to the heating-cooling process. Because the molecules were under lower energy levels and the molecular conformation was more ordered during the enzymatic triggeration under mild conditions, nanomaterials with higher supramolecular order could be obtained through biocatalytic control. In this study, nanoparticles were obtained by an enzymatic reaction and nanofibers were observed through the heating-cooling process. We observed a distinct trough at 318 nm from the CD spectrum of a particle sample but not a fiber sample, suggesting the long range arrangement of molecules and helicity in the nanoparticles. The nanoparticles with higher supramolecular order possessed much better potency as a protein vaccine adjuvant because it accelerated the DC maturation and elicited stronger T-cells cytokine production than the nanofibers. Our study demonstrated that biocatalytic triggering is a useful method for preparing supramolecular nanomaterials with higher supramolecular order and probably better bioactivity.We showed in this study that enzymatic triggering is a totally different pathway for the preparation of self-assembling nanomaterials to the heating-cooling process. Because the molecules were under lower energy levels and the molecular conformation was more ordered during the enzymatic triggeration under mild conditions, nanomaterials with higher supramolecular order could be obtained through biocatalytic control. In this study, nanoparticles were obtained by an enzymatic reaction and nanofibers were observed through the heating-cooling process. We observed a distinct trough at 318 nm from the CD spectrum of a particle sample but not a fiber sample, suggesting the long range arrangement of molecules and helicity in the nanoparticles. The nanoparticles with higher supramolecular order possessed much better potency as a protein vaccine

  3. Structural and synthetic studies of bioactive natural products

    OpenAIRE

    Heltzel, Carl E.

    1993-01-01

    As part of an ongoing investigation for anticancer agents from natural resources, four plant extracts were determined to contain interesting bioactivity. These extracts were separated by chromatography to afford a number of bioactive compounds that were characterized by spectral analysis. Fractionation of the fruit extract of Cryptocarya crassifolia led to the isolation of two known flavonoids and two known cryptocaryalactones. Fractionation of the bark extract of the same plant also g...

  4. Influence of Surface Treatments on the Bioactivity of Ti

    OpenAIRE

    Lindahl, Carl; Engqvist, Håkan; Xia, Wei

    2013-01-01

    Several techniques have been described to modify the surface of titanium to make it more bioactive. Heat treatment (HT) and sodium hydroxide treatment (NaOH) have been used and can change the crystallinity and surface chemistry of titanium implants. However, no studies have systemically focused on comparing these different methods and their effect on the bioactivity of Ti. Therefore, in this study, Ti substrates were systematically treated using HT, NaOH, and a combination of HT and NaOH. The...

  5. Minor bioactive compounds in milk and their determination

    OpenAIRE

    Kocmanová, Adéla

    2012-01-01

    Milk is an essential part of human nutrition at every stage of life, due to the balanced content of all necessary nutrients, valuable protein, lactose, fat and easily digestible bioactive minor components, especially vitamins and minerals. Milk is used as so - called ‘functional food’ due to its composition and positive effects on human health. Through the use of literature search it was possible to dispose compendium of minor bioactive substances found in milk and their effect on human he...

  6. Bioactive compounds of goat milk and their determination

    OpenAIRE

    Petránková, Barbora

    2013-01-01

    Summary Milk is for centuries the basic natural food of man. It is more than a source of nutrients. Due to its nutritional composition, specific effects on physiological and biochemical functions of the organism and the content of a wide range of bioactive substances, milk is ranked into the group of so-called functional foods. In this literature review was drawn sketch effect, particularly goat's milk, and it's bioactive substances on the human organism. At the end of this work are a...

  7. Monitoring Abacavir Bioactivation in Humans: Screening for an Aldehyde Metabolite

    OpenAIRE

    Grilo, N; Antunes, A.; Caixas, U; Marinho, A; Charneira, C; Oliveira, MC; Monteiro, E.; Marques, MM; Pereira, S

    2013-01-01

    The anti-HIV drug abacavir is associated with idiosyncratic hypersensitivity reactions and cardiotoxicity. Although the mechanism underlying abacavir-toxicity is not fully understood, drug bioactivation to reactive metabolites may be involved. This work was aimed at identifying abacavir-protein adducts in the hemoglobin of HIV patients as biomarkers of abacavir bioactivation and protein modification. The protocol received prior approval from the Hospital Ethics Committee, patients gave their ...

  8. Bioactivation of myelotoxic xenobiotics by human neutrophil myeloperoxidase

    International Nuclear Information System (INIS)

    Many environmental pollutants and drugs are toxic to the bone marrow. Some of these xenobiotics may initiate toxicity after undergoing bioactivation to free radicals and/or other reactive electrophiles. Peroxidases are a group of enzymes that catalyze the one-electron oxidative bioactivation of a variety of xenobiotics in vitro. Myeloperoxidase (MPO) is a peroxidative enzyme found in very high concentration in the neutrophils of human bone marrow. In this study, human MPO was evaluated to determine its ability to catalyze the in vitro bioactivation of known bone marrow toxicants that contain the aromatic hydroxyl (Ar-OH), aromatic amine (Ar-N-R2), or heterocyclic tertiary amine (double-bond N-R) moieties. The formation of free radical metabolites during the MPO-catalyzed bioactivation of hydroquinone and catechol (benzene metabolites), mitoxantrone and ametantrone (antitumor drugs), and chlorpromazine and promazine (antipsychotic drugs) was demonstrated by EPR spectroscopy. The reactivity of the products formed during the MPO catalyzed bioactivation of [14C]hydroquinone and [14C]catechol was shown by their covalent binding to protein and DNA in vitro. The covalently binding metabolite in each case is postulated to be the quinone form of the xenobiotic. In addition, both GSH and NADH were oxidized by the reactive intermediate(s) formed during the MPO-catalyzed bioactivation of many of the bone marrow toxicants tested. It was also shown that p,p-biphenol stimulated the MPO catalyzed bioactivation of both hydroquinone and catechol, while p-cresol stimulated the MPO-catalyzed bioactivation of catechol

  9. Food-Derived Bioactive Peptides on Inflammation and Oxidative Stress

    OpenAIRE

    Subhadeep Chakrabarti; Forough Jahandideh; Jianping Wu

    2014-01-01

    Chronic diseases such as atherosclerosis and cancer are now the leading causes of morbidity and mortality worldwide. Inflammatory processes and oxidative stress underlie the pathogenesis of these pathological conditions. Bioactive peptides derived from food proteins have been evaluated for various beneficial effects, including anti-inflammatory and antioxidant properties. In this review, we summarize the roles of various food-derived bioactive peptides in inflammation and oxidative stress and...

  10. Fabrication and in vitro biomineralization of bioactive glass (BG) nanofibres

    International Nuclear Information System (INIS)

    Bioactive glass nanofibres have excellent bioactivity and cell compatibility, and are regarded as a promising next-generation biomaterial in the bone-regeneration field. This paper is concentrated on the effect of electrospinning parameters on the diameter and morphology of bioactive glass nanofibres, and the process of in vitro biomineralization. In this work, sol-gel glass nanofibres with high bioactivity were prepared by electrospinning processing in the presence of poly(vinyl pyrrolidone) (PVP) and pluronic P123 (EO20-PO70-EO20) as chain entanglements. The influence of the polymer concentration, types of polymer and electric field strength on the fibre diameter was examined. The average diameter of these BG nanofibres could be controlled in the range from 85 to 400 nm. The addition of PVP resulted in sufficient chain entanglement and the formation of smooth BG nanofibres, and the addition of P123 led to a further decrease of the diameter with appropriate electric field strength, which held the balance between the electrostatic repulsive force and surface tension of the electrospinning solution. Furthermore, the early stage of in vitro biomineralization of the BG nanofibres in the simulated body fluid (SBF) was studied in this work. The behaviour of in vitro biomineralization of bioactive glass nanofibres was different to the conventional ones, and the structure of bioactive glasses contributed to the formation process of hydroxyapatite

  11. The Influence of Peptide Modifications of Bioactive Glass on Human Mesenchymal Stem Cell Growth and Function

    Science.gov (United States)

    Ammar, Mohamed

    2011-12-01

    Bioactive glass is known for its potential as a bone scaffold due to its ability to stimulate osteogenesis and induce bone formation. Broadening this potential to include the differentiation of human mesenchymal stem cells (hMSCs) to bone cells will enhance the healing process in bone defects. The surface of bioactive glass made by the sol-gel technique with the composition of 70% SiO2-30% CaO (mol %) was grafted with 3 peptides sequences in different combinations from proteins (fibronectin BMP-2 and BMP-9) that are known to promote the adhesion, differentiation and osteogenesis process. The experiment was done in two forms, a 2D non-porous thin film and a 3D nano-macroporous structure. hMSCs were grown on the materials for a total of five weeks. The 2D materials were tested for the expression of 3 osteogenic markers (osteopontin, osteocalcin and osteonectin) through immunocytochemistry. The 3D forms were monitored for cell's adhesion, morphology, spreading and proliferation by scanning electron microscopy, in addition to proliferation assay and alkaline phosphatase activity measurement. Results showed that hMSCs poorly adhered to the 2D thin films, but the few cells survived showed enhanced expression of the osteogenic markers. On the 3D form, cells showed enhanced proliferation at week one and more survival of the cells on the materials grafted with the adhesion peptide for the successive weeks in comparison to the positive control samples. Enhanced alkaline phosphatase activity was also detected compared to the negative control samples but were still below the positive control samples. In conclusion, the peptide grafting could increase the effect of bioactive glass but more peptide combinations should be examined to improve the effects on the differentiation and osteogenic activity of the hMSCs.

  12. Thermal decomposition of bioactive sodium titanate surfaces

    Science.gov (United States)

    Ravelingien, Matthieu; Mullens, Steven; Luyten, Jan; Meynen, Vera; Vinck, Evi; Vervaet, Chris; Remon, Jean Paul

    2009-09-01

    Alkali-treated orthopaedic titanium surfaces have earlier shown to induce apatite deposition. A subsequent heat treatment under air improved the adhesion of the sodium titanate layer but decreased the rate of apatite deposition. Furthermore, insufficient attention was paid to the sensitivity of titanium substrates to oxidation and nitriding during heat treatment under air. Therefore, in the present study, alkali-treated titanium samples were heat-treated under air, argon flow or vacuum. The microstructure and composition of their surfaces were characterized to clarify what mechanism is responsible for inhibiting in vitro calcium phosphate deposition after heat treatment. All heat treatments under various atmospheres turned out to be detrimental for apatite deposition. They led to the thermal decomposition of the dense sodium titanate basis near the interface with the titanium substrate. Depending on the atmosphere, several forms of Ti yO z were formed and Na 2O was sublimated. Consequently, less exchangeable sodium ions remained available. This pointed to the importance of the ion exchange capacity of the sodium titanate layer for in vitro bioactivity.

  13. Bioactivation of Phytoestrogens: Intestinal Bacteria and Health.

    Science.gov (United States)

    Landete, J M; Arqués, J; Medina, M; Gaya, P; de Las Rivas, B; Muñoz, R

    2016-08-17

    Phytoestrogens are polyphenols similar to human estrogens found in plants or derived from plant precursors. Phytoestrogens are found in high concentration in soya, flaxseed and other seeds, fruits, vegetables, cereals, tea, chocolate, etc. They comprise several classes of chemical compounds (stilbenes, coumestans, isoflavones, ellagitannins, and lignans) which are structurally similar to endogenous estrogens but which can have both estrogenic and antiestrogenic effects. Although epidemiological and experimental evidence indicates that intake of phytoestrogens in foods may be protective against certain chronic diseases, discrepancies have been observed between in vivo and in vitro experiments. The microbial transformations have not been reported so far in stilbenes and coumestans. However, isoflavones, ellagitanins, and lignans are metabolized by intestinal bacteria to produce equol, urolithins, and enterolignans, respectively. Equol, urolithin, and enterolignans are more bioavailable, and have more estrogenic/antiestrogenic and antioxidant activity than their precursors. Moreover, equol, urolithins and enterolignans have anti-inflammatory effects and induce antiproliferative and apoptosis-inducing activities. The transformation of isoflavones, ellagitanins, and lignans by intestinal microbiota is essential to be protective against certain chronic diseases, as cancer, cardiovascular disease, osteoporosis, and menopausal symptoms. Bioavailability, bioactivity, and health effects of dietary phytoestrogens are strongly determined by the intestinal bacteria of each individual. PMID:25848676

  14. Search for Hydrophilic Marine Fungal Metabolites: A Rational Approach for Their Production and Extraction in a Bioactivity Screening Context

    Directory of Open Access Journals (Sweden)

    Jean-François Biard

    2011-01-01

    Full Text Available In the search for bioactive natural products, our lab screens hydrophobic extracts from marine fungal strains. While hydrophilic active substances were recently identified from marine macro-organisms, there was a lack of reported metabolites in the marine fungi area. As such, we decided to develop a general procedure for screening of hydrophobic metabolites. The aim of this study was to compare different processes of fermentation and extraction, using six representative marine fungal strains, in order to define the optimized method for production. The parameters studied were (a which polar solvent to select, (b which fermentation method to choose between solid and liquid cultures, (c which raw material, the mycelium or its medium, to extract and (d which extraction process to apply. The biochemical analysis and biological evaluations of obtained extracts led to the conclusion that the culture of marine fungi by agar surface fermentation followed by the separate extraction of the mycelium and its medium by a cryo-crushing and an enzymatic digestion with agarase, respectively, was the best procedure when screening for hydrophilic bioactive metabolites. During this development, several bioactivities were detected, confirming the potential of hydrophilic crude extracts in the search for bioactive natural products.

  15. In vitro study of improved wound-healing effect of bioactive borate-based glass nano-/micro-fibers.

    Science.gov (United States)

    Yang, Qingbo; Chen, Sisi; Shi, Honglan; Xiao, Hai; Ma, Yinfa

    2015-10-01

    Because of the promising wound-healing capability, bioactive glasses have been considered as one of the next generation hard- and soft-tissue regeneration materials. The lack of understanding of the substantial mechanisms, however, indicates the need for further study on cell-glass interactions to better interpret the rehabilitation capability. In the present work, three bioactive glass nano-/micro-fibers, silicate-based 45S5, borate-based 13-93B3 and 1605 (additionally doped with copper oxide and zinc oxide), were firstly compared for their in vitro soaking/conversion rate. The results of elemental monitoring and electron microscopic characterization demonstrated that quicker ion releasing and glass conversion occurred in borate-based fibers than that of silicate-based one. This result was also reflected by the formation speed of hydroxyapatite (HA). This process was further correlated with original boron content and surrounding rheological condition. We showed that an optimal fiber pre-soaking time (or an ideal dynamic flow rate) should exist to stimulate the best cell proliferation and migration ability. Moreover, 13-93B3 and 1605 fibers showed different glass conversion and biocompatibility properties as well, indicating that trace amount variation in composition can also influence fiber's bioactivity. In sum, our in vitro rheological module closely simulated in vivo niche environment and proved a potentially improved wound-healing effect by borate-based glass fibers, and the results shall cast light on future improvement in bioactive glass fabrication. PMID:26117744

  16. Electrospinning of Bioactive Dex-PAA Hydrogel Fibers

    Science.gov (United States)

    Louie, Katherine Boyook

    In this work, a novel method is developed for making nano- and micro-fibrous hydrogels capable of preventing the rejection of implanted materials. This is achieved by either (1) mimicking the native cellular environment, to exert fine control over the cellular response or (2) acting as a protective barrier, to camouflage the foreign nature of a material and evade recognition by the immune system. Comprehensive characterization and in vitro studies described here provide a foundation for developing substrates for use in clinical applications. Hydrogel dextran and poly(acrylic acid) (PAA) fibers are formed via electrospinning, in sizes ranging from nanometers to microns in diameter. While "as-electrospun" fibers are continuous in length, sonication is used to fragment fibers into short fiber "bristles" and generate nano- and micro- fibrous surface coatings over a wide range of topographies. Dex-PAA fibrous surfaces are chemically modified, and then optimized and characterized for non-fouling and ECM-mimetic properties. The non-fouling nature of fibers is verified, and cell culture studies show differential responses dependent upon chemical, topographical and mechanical properties. Dex-PAA fibers are advantageously unique in that (1) a fine degree of control is possible over three significant parameters critical for modifying cellular response: topography, chemistry and mechanical properties, over a range emulating that of native cellular environments, (2) the innate nature of the material is non-fouling, providing an inert background for adding back specific bioactive functionality, and (3) the fibers can be applied as a surface coating or comprise the scaffold itself. This is the first reported work of dex-PAA hydrogel fibers formed via electrospinning and thermal cross-linking, and unique to this method, no toxic solvents or cross-linking agents are needed to create hydrogels or for surface attachment. This is also the first reported work of using sonication to

  17. Nanomodified Peek Dental Implants: Bioactive Composites and Surface Modification—A Review

    OpenAIRE

    Shariq Najeeb; Zohaib Khurshid; Jukka Pekka Matinlinna; Fahad Siddiqui; Mohammad Zakaria Nassani; Kusai Baroudi

    2015-01-01

    Purpose. The aim of this review is to summarize and evaluate the relevant literature regarding the different ways how polyetheretherketone (PEEK) can be modified to overcome its limited bioactivity, and thereby making it suitable as a dental implant material. Study Selection. An electronic literature search was conducted via the PubMed and Google Scholar databases using the keywords “PEEK dental implants,” “nano,” “osseointegration,” “surface treatment,” and “modification.” A total of 16 in v...

  18. Aquasomes: Self-assembled systems for the delivery of bioactive molecules

    Directory of Open Access Journals (Sweden)

    Neha Narang

    2012-01-01

    Full Text Available Nanocarriers increase the therapeutic efficacy of the pharmaceutically active agents as they can regulate their release, improve their stability and prolong circulation time by protecting the drug from phagocytosis and premature degradation. These delivery vehicles have the potential to augment the pharmacodynamic and pharmacokinetic profiles of drug molecules, thereby enhancing the therapeutic efficacy of the pharmaceutical agents. Nanoparticles which are fabricated from ceramics consist of a hydroxyapatite core whose surface is noncovalently modified by oligosaccharide on which bioactive material/drug can be absorbed, are known as "aquasomes." This review involves properties, advantages, preparation methods, evaluation, and applications of aquasomes.

  19. PROCESSING AND CHARACTERISATION OF HIGH-VELOCITY SUSPENSION FLAME SPRAYED (HVSFS) BIOACTIVE GLASS COATINGS

    OpenAIRE

    GIOVANNI BOLELLI; VALERIA CANNILLO; RAINER GADOW; ANDREAS KILLINGER; LUCA LUSVARGHI; JOHANNES RAUCH

    2010-01-01

    The High-Velocity Suspension Flame Spraying (HVSFS) technique was employed in order to deposit bioactive glass coatings onto titanium substrates. Two different glass compositions were examined: the classical 45S5 Bioglass and a newly-developed SiO2–CaO–K2O–P2O5 glass, labelled as “Bio-K”. Suitable raw materials were melted in a furnace and fritted by casting into water. The frit was dry-milled in a porcelain jar and subsequently attrition-milled in isopropanol. The resulting micronsized powde...

  20. Bioactive Wollastonite-Diopside Foams from Preceramic Polymers and Reactive Oxide Fillers

    OpenAIRE

    Laura Fiocco; Hamada Elsayed; Letizia Ferroni; Chiara Gardin; Barbara Zavan; Enrico Bernardo

    2015-01-01

    Wollastonite (CaSiO3) and diopside (CaMgSi2O6) silicate ceramics have been widely investigated as highly bioactive materials, suitable for bone tissue engineering applications. In the present paper, highly porous glass-ceramic foams, with both wollastonite and diopside as crystal phases, were developed from the thermal treatment of silicone polymers filled with CaO and MgO precursors, in the form of micro-sized particles. The foaming was due to water release, at low temperature, in the polyme...

  1. Crystalline Bioceramic Materials

    OpenAIRE

    Aza Moya, Antonio H. de; Aza, Piedad N. de; Aza Pendas, Salvador de

    2005-01-01

    [EN] A strong interest in the use of ceramics for biomedical engineering applications developed in the late 1960´s. Used initially as alternatives to metallic materials in order to increase the biocompatibility of implants, bioceramics have become a diverse class of biomaterials, presently including three basic types: relatively bioinert ceramics; bioactive or surface reactive bioceramics and bioresorbable ceramics. This review will only refer to bioceramics “sensus stricto”, it i...

  2. Characterization and bioactivity of nano-submicro octacalcium phosphate/gelatin composite

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Kei-ichiro [Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, Sendai (Japan); Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai (Japan); Anada, Takahisa; Honda, Yoshitomo [Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, Sendai (Japan); Shiwaku, Yukari [Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, Sendai (Japan); Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry, Sendai (Japan); Kawai, Tadashi; Echigo, Seishi; Takahashi, Tetsu [Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai (Japan); Suzuki, Osamu, E-mail: suzuki-o@m.tohoku.ac.jp [Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, Sendai (Japan)

    2013-10-01

    The present study was designed to investigate the physicochemical and bioactive properties of a nano-submicro sized octacalcium phosphate (OCP)-dispersed gelatin (Gel) composite (nano-submicro OCP/Gel) used as a bone substitute material in various bone defects. Well-grown, synthesized OCP was mechanically ground from 100 to 300 μm-sieved granules to particles that were approximately 500 nm in size. Then, 50 wt% of the nano-submicro OCP was mixed with porcine skin-derived acid extracted gelatin. The mixture was molded and lyophilized and then subjected to dehydrothermal crosslinking. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy showed that the structure of OCP was retained even after mechanical grinding to a nano-submicro scale level as well as inclusion in the Gel matrix. The bioactivity of nano-submicro OCP/Gel was examined by immersing the composite in simulated body fluid (SBF) for 7 days and by implanting it in rat critical-sized calvaria defects for 8 weeks. The nano-submicro OCP tended to convert to low crystalline hydroxyapatite (HA) in SBF as assessed by XRD. The nano-submicro OCP/Gel exhibited osteoconductivity in vivo, yielding new bone formation that was closely associated with the implanted composite. These results suggest that the nano-submicro OCP/Gel composite exhibits similar osteoconductivity as observed in other OCP-based materials previously reported and could be used as a bone substitute material for repairing various defects in bone.

  3. Characterization and bioactivity of nano-submicro octacalcium phosphate/gelatin composite

    International Nuclear Information System (INIS)

    The present study was designed to investigate the physicochemical and bioactive properties of a nano-submicro sized octacalcium phosphate (OCP)-dispersed gelatin (Gel) composite (nano-submicro OCP/Gel) used as a bone substitute material in various bone defects. Well-grown, synthesized OCP was mechanically ground from 100 to 300 μm-sieved granules to particles that were approximately 500 nm in size. Then, 50 wt% of the nano-submicro OCP was mixed with porcine skin-derived acid extracted gelatin. The mixture was molded and lyophilized and then subjected to dehydrothermal crosslinking. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy showed that the structure of OCP was retained even after mechanical grinding to a nano-submicro scale level as well as inclusion in the Gel matrix. The bioactivity of nano-submicro OCP/Gel was examined by immersing the composite in simulated body fluid (SBF) for 7 days and by implanting it in rat critical-sized calvaria defects for 8 weeks. The nano-submicro OCP tended to convert to low crystalline hydroxyapatite (HA) in SBF as assessed by XRD. The nano-submicro OCP/Gel exhibited osteoconductivity in vivo, yielding new bone formation that was closely associated with the implanted composite. These results suggest that the nano-submicro OCP/Gel composite exhibits similar osteoconductivity as observed in other OCP-based materials previously reported and could be used as a bone substitute material for repairing various defects in bone.

  4. Tough, bio-inspired hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Munch, Etienne; Launey, Maximimilan E.; Alsem, Daan H.; Saiz, Eduardo; Tomsia, Antoni P.; Ritchie, Robert O.

    2008-10-06

    The notion of mimicking natural structures in the synthesis of new structural materials has generated enormous interest but has yielded few practical advances. Natural composites achieve strength and toughness through complex hierarchical designs extremely difficult to replicate synthetically. Here we emulate Nature's toughening mechanisms through the combination of two ordinary compounds, aluminum oxide and polymethylmethacrylate, into ice-templated structures whose toughness can be over 300 times (in energy terms) that of their constituents. The final product is a bulk hybrid ceramic material whose high yield strength and fracture toughness ({approx}200 MPa and {approx}30 MPa{radical}m) provide specific properties comparable to aluminum alloys. These model materials can be used to identify the key microstructural features that should guide the synthesis of bio-inspired ceramic-based composites with unique strength and toughness.

  5. A bioactive formulation based on Fragaria vesca L. vegetative parts: chemical characterisation and application in κ-carrageenan gelatin

    OpenAIRE

    Dias, Maria Inês; Barros, Lillian; Fernandes, Isabel Patrícia; Ruphuy, G.; Oliveira, M. B. P. P.; Santos-Buelga, Celestino; Barreiro, M.F.; Ferreira, Isabel C. F. R.

    2015-01-01

    A bioactive formulation based on the vegetative parts of the wild strawberry, Fragaria vesca L., was developed by using a microencapsulated extract (lyophilized infusion form). For that purpose, a process based on an atomization/coagulation technique with alginate as the wall material was applied. Among the tested hydromethanolic and aqueous extracts, both obtained from wild and commercial samples, the infusion of a wild species emerged as the most antioxidative one. The higher amounts of fla...

  6. Physical Properties, Lung Deposition Modeling, And Bioactivity Of Recombinant Gm-Csf Aerosolised With A Highly Efficient Nebulizer

    OpenAIRE

    Luisetti, Maurizio; Kroneberg, Philipp; Suzuki, Takuji; Kadija, Zamir; Muellinger, Bernhard; Campo, Ilaria; Gleske, Juliane; Rodi, Giuseppe; Zimlich, William C; Mariani, Francesca; Ferrari, Fabio; Frey, Manuel; Trapnell, Bruce C.

    2011-01-01

    Abstract Pulmonary alveolar proteinosis (PAP) is a rare condition characterized by the accumulation of lipoproteinaceous material within air spaces. Although whole lung lavage is the current standard of care, recent advances in our understanding of PAP pathophysiology suggest that the disorder may benefit from inhalation of recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF). The aim of this study was to determine the physical properties and bioactivity of rGM-CS...

  7. The Effect of Exposed Glass Fibers and Particles of Bioactive Glass on the Surface Wettability of Composite Implants

    OpenAIRE

    Abdulmajeed, Aous A.; Lippo V. Lassila; Vallittu, Pekka K.; Timo O. Närhi

    2011-01-01

    Measurement of the wettability of a material is a predictive index of cytocompatibility. This study was designed to evaluate the effect of exposed E-glass fibers and bioactive glass (BAG) particles on the surface wettability behavior of composite implants. Two different groups were investigated: (a) fiber reinforced composites (FRCs) with different fiber orientations and (b) polymer composites with different wt. % of BAG particles. Photopolymerized and heat postpolymerized composite substrate...

  8. Effect of particle size on the in vitro bioactivity, hydrophilicity and mechanical properties of bioactive glass-reinforced polycaprolactone composites

    Energy Technology Data Exchange (ETDEWEB)

    Tamjid, E. [Institute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of); Bagheri, R., E-mail: rezabagh@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of); Vossoughi, M. [Institute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of); Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of); Simchi, A., E-mail: simchi@sharif.edu [Institute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of); Department of Materials Science and Engineering, Sharif University of Technology, Azadi Ave. P.O. Box: 11365-9466, 14588 Tehran (Iran, Islamic Republic of)

    2011-10-10

    Polycaprolactone (PCL) composite films containing 5 wt.% bioactive glass (BG) particles of different sizes (6 {mu}m, 250 nm, < 100 nm) were prepared by solvent casting methods. The ultra-fine BG particles were prepared by high-energy mechanical milling of commercial 45S5 Bioglass (registered) particles. The characteristics of bioactive glass particles were studied by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and X-ray diffraction (XRD) methods. In vitro bioactivity of the PCL/BG composite films was evaluated through immersion in the simulated body fluid (SBF). The films were analyzed by FE-SEM, energy dispersive spectrometry (EDS), XRD, and atomic force microscopy (AFM). The mechanical properties of highly-porous PCL/BG composites were examined on cylindrical specimens under quasi-static compression load. It was found that partial crystallization of amorphous BG particles during a prolonged mechanical milling occurred and calcium silicate (CaSiO{sub 3}) and sodium calcium silicate (Na{sub 2}CaSiO{sub 4}) phases were formed. The introduction of submicron BG particles (250 nm) was shown to improve the bioactivity of PCL films. In contrast to BG microparticles, the submicron BG particles were distributed on the film surfaces, providing a high surface exposure to SBF with an improved nanotopography. A notable increase in the stiffness and elastic modulus of the composite was also obtained. As compared to submicron BG particles, lower bioactivity and elastic modulus were acquired for PCL/BG nanoparticles. It was also shown that in spite of high specific surface area of the nanoparticles, partial crystallization during mechanical milling and agglomeration of the nanoparticles during processing decrease the bioactivity, hydrophilicity and mechanical response of the BG-reinforced PCL composites. Highlights: {yields} The effect of Bioglass particle size on the in vitro bioactivity of

  9. Radiation Parameters of Some Potential Bioactive Compounds

    Institute of Scientific and Technical Information of China (English)

    Zeynep Gedik; Mehtap Tugrak; Aysenur Dastan; Haliseinci Gul; Demet YIlmaz

    2015-01-01

    In this study ,we aimed to determine the radiation parameters of some potential bioactive com‐pounds .1‐Aryl‐3‐dibenzylamino‐propane‐1‐on hydrochloride type Mannich bases were synthesized via classical conventional heating method .Aryl part was changed as phenyl (C6 H5 ) ,4‐methylphenyl (4‐CH3 C6 H4 ) ,4‐flu‐orophenyl (4‐FC6 H4 ) , 4‐nitrophenyl (4‐NO2 C6 H4 ) , 4‐chlorophenyl (4‐ClC6 H4 ) , 4‐bromophenyl (4‐BrC6 H4 ) ,and 2‐thienyl (C4 H3 S‐2‐yl) .Mass attenuation coefficient (μm ) ,effective atomic number (Zef ) and effective electron density (Nel ) of compounds were determined experimentally and theoretically for at 8.040 , 8.910 ,13.40 ,14.96 ,17.48 ,19.61 ,22.16 ,24.94 ,32.19 ,36.38 ,44.48 ,50.38 and 59.54 keV photon en‐ergies by using an HPGe detector with a resolution of 182 eV at 5.9 keV .Radiation parameters of these com‐pounds which can be anti‐cancer drug candidate were given in the tables .The results show that phenyl ring be‐have like thiophene ring in terms of radiation absorption .It is thought that the results of study may drive allow the development of drug candidate new compounds in medical oncology .

  10. Significant degradability enhancement in multilayer coating of polycaprolactone-bioactive glass/gelatin-bioactive glass on magnesium scaffold for tissue engineering applications

    Science.gov (United States)

    Yazdimamaghani, Mostafa; Razavi, Mehdi; Vashaee, Daryoosh; Pothineni, Venkata Raveendra; Rajadas, Jayakumar; Tayebi, Lobat

    2015-05-01

    Magnesium (Mg) is a promising candidate to be used in medical products especially as bone tissue engineering scaffolds. The main challenge for using Mg in biomedical applications is its high degradation rate in the body. For this reason, in this study, a multilayer polymeric layer composed of polycaprolactone (PCL) and gelatin (Gel) reinforced with bioactive glass (BaG) particles has been applied on the surface of Mg scaffolds. The materials characteristics of uncoated Mg scaffold, Mg scaffold coated only with PCL-BaG and Mg scaffold coated with PCL-BaG and Gel-BaG have been analyzed and compared in detail. Scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) were utilized for microstructural studies. In vitro bioactivity and biodegradation evaluations were carried out by submerging the scaffolds in simulated body fluid (SBF) at pre-determined time points. The results demonstrated that Mg scaffold coated with PCL-BaG and Gel-BaG exhibited significant improvement in biodegradability.

  11. Bioactivity response of Ta1-xOx coatings deposited by reactive DC magnetron sputtering.

    Science.gov (United States)

    Almeida Alves, C F; Cavaleiro, A; Carvalho, S

    2016-01-01

    The use of dental implants is sometimes accompanied by failure due to periimplantitis disease and subsequently poor esthetics when soft-hard tissue margin recedes. As a consequence, further research is needed for developing new bioactive surfaces able to enhance the osseous growth. Tantalum (Ta) is a promising material for dental implants since, comparing with titanium (Ti), it is bioactive and has an interesting chemistry which promotes the osseointegration. Another promising approach for implantology is the development of implants with oxidized surfaces since bone progenitor cells interact with the oxide layer forming a diffusion zone due to its ability to bind with calcium which promotes a stronger bond. In the present report Ta-based coatings were deposited by reactive DC magnetron sputtering onto Ti CP substrates in an Ar+O2 atmosphere. In order to assess the osteoconductive response of the studied materials, contact angle and in vitro tests of the samples immersed in Simulated Body Fluid (SBF) were performed. Structural results showed that oxide phases where achieved with larger amounts of oxygen (70 at.% O). More compact and smooth coatings were deposited by increasing the oxygen content. The as-deposited Ta coating presented the most hydrophobic character (100°); with increasing oxygen amount contact angles progressively diminished, down to the lowest measured value, 63°. The higher wettability is also accompanied by an increase on the surface energy. Bioactivity tests demonstrated that highest O-content coating, in good agreement with wettability and surface energy values, showed an increased affinity for apatite adhesion, with higher Ca/P ratio formation, when compared to the bare Ti substrates. PMID:26478293

  12. Processing of novel bioactive polymeric matrixes for tissue engineering using supercritical fluid technology

    International Nuclear Information System (INIS)

    The aim of this study was to develop a new process for the production of bioactive 3D scaffolds using a clean and environmentally friendly technology. The possibility of preparing composite scaffolds of Bioglass and a polymeric blend of starch and poly(L-lactic acid) (SPLA50) was evaluated. Supercritical phase-inversion technique was used to prepare inorganic particles loaded starch-based porous composite matrixes in a one-step process for bone tissue engineering purposes. Due to their osteoconductive properties some glasses and ceramics are interesting materials to be used for bone tissue engineering purposes; however their poor mechanical properties create the need of a polymeric support where the inorganic fraction can be dispersed. Samples impregnated with different concentrations of Bioglass (10 and 15% wt/wt polymer) were prepared at 200 bar and 55 deg. C. The presence of Bioglass did not affect the porosity or interconnectivity of the polymeric matrixes. Dynamic mechanical analysis has proven that the modulus of the SPLA50 scaffolds increases when glass particles are impregnated within the matrix. In vitro bioactivity studies were carried out using simulated body fluid and the results show that a calcium-phosphate layer started to be formed after only 1 day of immersion. Chemical analysis of the apatite layer formed on the surface of the scaffold was performed by different techniques, namely EDS and FTIR spectroscopy and X-ray diffraction (XRD). The ion concentration in the simulated body fluid was also carried out by ICP analysis. Results suggest that a bone-like apatite layer was formed. This study reports the feasibility of using supercritical fluid technology to process, in one step, a porous matrix loaded with a bioactive material for tissue engineering purposes.

  13. Kinetic neutron diffraction and SANS studies of phase formation in bioactive machinable glass ceramics

    International Nuclear Information System (INIS)

    Bioactive fluormica-fluorapatite glass-ceramic materials offer a very encouraging solution to the problem of efficient restoration and reconstruction of hard tissues. To produce material with the desired crystalline phases, a five-stage heat treatment must be performed. This thermal processing has a large impact on the microstructure and ultimately the final mechanical properties of the materials. We have examined the thermal processing of one of our most promising machinable biomaterials, using time-resolved small angle neutron scattering and neutron diffraction to study the nucleation and growth of crystallites. The processing route had already been optimized by studying the properties of quenched samples using x-ray diffraction, mechanical measurements and differential thermal analysis. However these results show that the heat treatment can be further optimized in terms of crystal nucleation, and we show that these techniques are the only methods by which a truly optimized thermal processing route may be obtained

  14. Sources and Bioactive Properties of Conjugated Dietary Fatty Acids.

    Science.gov (United States)

    Hennessy, Alan A; Ross, Paul R; Fitzgerald, Gerald F; Stanton, Catherine

    2016-04-01

    The group of conjugated fatty acids known as conjugated linoleic acid (CLA) isomers have been extensively studied with regard to their bioactive potential in treating some of the most prominent human health malignancies. However, CLA isomers are not the only group of potentially bioactive conjugated fatty acids currently undergoing study. In this regard, isomers of conjugated α-linolenic acid, conjugated nonadecadienoic acid and conjugated eicosapentaenoic acid, to name but a few, have undergone experimental assessment. These studies have indicated many of these conjugated fatty acid isomers commonly possess anti-carcinogenic, anti-adipogenic, anti-inflammatory and immune modulating properties, a number of which will be discussed in this review. The mechanisms through which these bioactivities are mediated have not yet been fully elucidated. However, existing evidence indicates that these fatty acids may play a role in modulating the expression of several oncogenes, cell cycle regulators, and genes associated with energy metabolism. Despite such bioactive potential, interest in these conjugated fatty acids has remained low relative to the CLA isomers. This may be partly attributed to the relatively recent emergence of these fatty acids as bioactives, but also due to a lack of awareness regarding sources from which they can be produced. In this review, we will also highlight the common sources of these conjugated fatty acids, including plants, algae, microbes and chemosynthesis. PMID:26968402

  15. Bioinformatics approaches for identifying new therapeutic bioactive peptides in food

    Directory of Open Access Journals (Sweden)

    Nora Khaldi

    2012-10-01

    Full Text Available ABSTRACT:The traditional methods for mining foods for bioactive peptides are tedious and long. Similar to the drug industry, the length of time to identify and deliver a commercial health ingredient that reduces disease symptoms can take anything between 5 to 10 years. Reducing this time and effort is crucial in order to create new commercially viable products with clear and important health benefits. In the past few years, bioinformatics, the science that brings together fast computational biology, and efficient genome mining, is appearing as the long awaited solution to this problem. By quickly mining food genomes for characteristics of certain food therapeutic ingredients, researchers can potentially find new ones in a matter of a few weeks. Yet, surprisingly, very little success has been achieved so far using bioinformatics in mining for food bioactives.The absence of food specific bioinformatic mining tools, the slow integration of both experimental mining and bioinformatics, and the important difference between different experimental platforms are some of the reasons for the slow progress of bioinformatics in the field of functional food and more specifically in bioactive peptide discovery.In this paper I discuss some methods that could be easily translated, using a rational peptide bioinformatics design, to food bioactive peptide mining. I highlight the need for an integrated food peptide database. I also discuss how to better integrate experimental work with bioinformatics in order to improve the mining of food for bioactive peptides, therefore achieving a higher success rates.

  16. Immense Essence of Excellence: Marine Microbial Bioactive Compounds

    Directory of Open Access Journals (Sweden)

    Ira Bhatnagar

    2010-10-01

    Full Text Available Oceans have borne most of the biological activities on our planet. A number of biologically active compounds with varying degrees of action, such as anti-tumor, anti-cancer, anti-microtubule, anti-proliferative, cytotoxic, photo protective, as well as antibiotic and antifouling properties, have been isolated to date from marine sources. The marine environment also represents a largely unexplored source for isolation of new microbes (bacteria, fungi, actinomycetes, microalgae-cyanobacteria and diatoms that are potent producers of bioactive secondary metabolites. Extensive research has been done to unveil the bioactive potential of marine microbes (free living and symbiotic and the results are amazingly diverse and productive. Some of these bioactive secondary metabolites of microbial origin with strong antibacterial and antifungal activities are being intensely used as antibiotics and may be effective against infectious diseases such as HIV, conditions of multiple bacterial infections (penicillin, cephalosporines, streptomycin, and vancomycin or neuropsychiatric sequelae. Research is also being conducted on the general aspects of biophysical and biochemical properties, chemical structures and biotechnological applications of the bioactive substances derived from marine microorganisms, and their potential use as cosmeceuticals and nutraceuticals. This review is an attempt to consolidate the latest studies and critical research in this field, and to showcase the immense competence of marine microbial flora as bioactive metabolite producers. In addition, the present review addresses some effective and novel approaches of procuring marine microbial compounds utilizing the latest screening strategies of drug discovery.

  17. Fatty Acids and Bioactive Lipids of Potato Cultivars: An Overview.

    Science.gov (United States)

    Ramadan, Mohamed Fawzy; Oraby, Hesahm Farouk

    2016-01-01

    Potato tuber is a highly nutritious, wherein genotype and environmental differences are known to exist in the shape, size and nutritional value of potatoes. Owing to its high consumption, potato could be an ideal carrier of health-promoting phytochemicals. Potato cultivars contain many bioactive lipidic compounds such as fatty acids, glycolipids, phospholipids, sterols, tocols and carotenoids, which are highly desirable in diet because of their health-promoting effects. In the scientific literature, information on the content and profile of bioactive lipidic compounds in potato cultivars are few. The concentration and stability of bioactive lipids are affected by many factors such as genotype, agronomic factors, postharvest storage, cooking and processing conditions. In this review levels and composition of bioactive lipids in terms of lipid classes, fatty acids, phytosterols, tocopherols, and caroteinoids distribution in different potato cultivars including genetically modified potato (GMP) were highlighted and discussed. In addition, factors affecting bioactive lipids levels, stability and health benefits are reviewed. In consideration of potential nutritional value, detailed knowledge on lipids of potato cultivars is of major importance. PMID:27250559

  18. Biocompatibility and bioactivity of calcium silicate-based endodontic sealers in human dental pulp cells

    Directory of Open Access Journals (Sweden)

    Leticia Boldrin MESTIERI

    2015-10-01

    Full Text Available Mineral Trioxide Aggregate (MTA is a calcium silicate-based material. New sealers have been developed based on calcium silicate as MTA Fillapex and MTA Plus.Objective The aim of this study was to evaluate biocompatibility and bioactivity of these two calcium silicate-based sealers in culture of human dental pulp cells (hDPCs.Material and Methods The cells were isolated from third molars extracted from a 16-year-old patient. Pulp tissue was sectioned into fragments with approximately 1 mm3 and kept in supplemented medium to obtain hDPCs adherent cultures. Cell characterization assays were performed to prove the osteogenic potential. The evaluated materials were: MTA Plus (MTAP; MTA Fillapex (MTAF and FillCanal (FC. Biocompatibility was evaluated with MTT and Neutral Red (NR assays, after hDPCs exposure for 24 h to different dilutions of each sealer extract (1:2, 1:3 and 1:4. Unexposed cells were the positive control (CT. Bioactivity was assessed by alkaline phosphatase (ALP enzymatic assay in cells exposed for one and three days to sealer extracts (1:4 dilution. All data were analyzed by ANOVA and Tukey post-test (p≤0.05%.Results MTT and NR results showed suitable cell viability rates for MTAP at all dilutions (90-135%. Cells exposed to MTAF and FC (1:2 and 1:4 dilutions showed significant low viability rate when compared to CT in MTT. The NR results demonstrated cell viability for all materials tested. In MTAP group, the cells ALP activity was similar to CT in one and three days of exposure to the material. MTAF and FC groups demonstrated a decrease in ALP activity when compared to CT at both periods of cell exposure.Conclusions The hDPCs were suitable for the evaluation of new endodontic materialsin vitro. MTAP may be considered a promising material for endodontic treatments.

  19. Microwave energy-assisted formation of bioactive CaO–MgO–SiO$_2$ ternary glass from bio-wastes

    Indian Academy of Sciences (India)

    ENOBONG R ESSIEN; VIOLETTE N ATASIE; ESTHER U UDOBANG

    2016-08-01

    Regeneration technique is extensively being sought after as a means of achieving bone repair without adverse immunological response. Silicate-based bioactive glasses containing Mg are gaining increasing attention for their biocompatibility. The current work has been focused on designing a facile and economic route using bio-wastes for synthesizing bioactive glasses in the CaO–MgO–SiO$_2$ system. Rice husk ash (RHA) obtained from burning ricehusk was used as silica source, while Ca was extracted from eggshells for preparing the glass through a modified sol–gel approach. The gel formed was irradiated in microwave before sintering at 950$^{\\circ}$C for 3 h. Thereafter, bioactivity test was conducted on the samples in simulated body fluid (SBF) at physiological conditions for a maximum of 14 days. Characterization of samples were performed before and after immersion in SBF to evaluate thecomposition, morphology and phases present in the glass using energy-dispersive X-ray analysis, scanning electron microscopy and X-ray diffraction. Apatite formation was confirmed using Fourier transform infrared spectroscopy.Results obtained showed the presence of diopside, wollastonite and pseudo-wollastonite as major bioactive phases. Hydroxyapatite formed on the material within 3 days in SBF, indicating good bioactivity.

  20. Multifunctional bioactive and improving the performance durability nanocoatings for finishing PET/CO woven fabrics by the sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Kowalczyk, Dorota, E-mail: dkowalczyk@iw.lodz.pl; Brzeziński, Stefan; Kamińska, Irena

    2015-11-15

    The paper presents the results of studies on multifunctional thin-coatings of textiles, simultaneously imparting to them bioactive properties in relations to bacteria and fungi as well as an increased abrasion resistance and anti-pilling effect with the use of modified hybrid materials produced by the sol–gel method from two precursors: (3-glycidoxypropyl)trimethoxysilane (GPTMS) and aluminum isopropoxide (ALIPO). The sol obtained was modified with bioactive particles in the form of nanopowder of metallic silver and copper alloy (Ag/Cu). Al{sub 2}O{sub 3}/SiO{sub 2} sol containing nanoparticles of Ag/Cu alloy was deposited on a polyester/cotton blend woven fabric (PET/CO 67/33) by the padding method. After drying and curing process, a thin and elastic bioactive silica coating was obtained on the fabric fibers surfaces. The fabrics with deposited nanocoatings were characterized by very good bioactive properties and increased resistance to abrasion and formation of pilling. - Highlights: • Multifunctional thin coating layer was prepared on the fabric using sol–gel method. • Modification of the hybrid Al{sub 2}O{sub 3}/SiO{sub 2} sol by Ag/Cu alloy nanoparticles. • Bioactive fabric created by deposition of Al{sub 2}O{sub 3}/SiO{sub 2} sol with Ag/Cu. • 30% increase the abrasion resistance of the thin coating fabric.

  1. Multifunctional bioactive and improving the performance durability nanocoatings for finishing PET/CO woven fabrics by the sol–gel method

    International Nuclear Information System (INIS)

    The paper presents the results of studies on multifunctional thin-coatings of textiles, simultaneously imparting to them bioactive properties in relations to bacteria and fungi as well as an increased abrasion resistance and anti-pilling effect with the use of modified hybrid materials produced by the sol–gel method from two precursors: (3-glycidoxypropyl)trimethoxysilane (GPTMS) and aluminum isopropoxide (ALIPO). The sol obtained was modified with bioactive particles in the form of nanopowder of metallic silver and copper alloy (Ag/Cu). Al2O3/SiO2 sol containing nanoparticles of Ag/Cu alloy was deposited on a polyester/cotton blend woven fabric (PET/CO 67/33) by the padding method. After drying and curing process, a thin and elastic bioactive silica coating was obtained on the fabric fibers surfaces. The fabrics with deposited nanocoatings were characterized by very good bioactive properties and increased resistance to abrasion and formation of pilling. - Highlights: • Multifunctional thin coating layer was prepared on the fabric using sol–gel method. • Modification of the hybrid Al2O3/SiO2 sol by Ag/Cu alloy nanoparticles. • Bioactive fabric created by deposition of Al2O3/SiO2 sol with Ag/Cu. • 30% increase the abrasion resistance of the thin coating fabric

  2. Silicon Utilizing Microbial Bioactivities in the Biosphere

    Science.gov (United States)

    Sen, M. M.; Das, S.

    2012-12-01

    potential as a source of biomass for the production of biofuels, due to their high growth rates and high cellular lipid content. Petroleum pollutant degradation can also be done by these organisms-Achanthes minutissima has degradable effects involving petroleum hydocarbons. Stephanopyxis turris a silicon utilizing organism releases a blend of chlorinated C8 hydrocarbons. This adds a fundamentally new pathway to the limited set of halogenating enzymatic activities known from nature. Many silicon utilizing organisms can produce PUFA from saturated fatty acids which ultimately produce many important bioactive chemicals like hormosirene, finaverrene, heptadienal, dietyopterene, cystophorene, decadienal. Trienoic acid, octadiene and many other important agents. Similarly terpenoid biosynthetic pathway is activated by them with formation of diterpenoids, sesterpenoids, triterpenoids and sterols.

  3. Chemically engineered extracts: source of bioactive compounds.

    Science.gov (United States)

    Ramallo, I Ayelen; Salazar, Mario O; Mendez, Luciana; Furlan, Ricardo L E

    2011-04-19

    Biological research and drug discovery critically depend on access to libraries of small molecules that have an affinity for biomacromolecules. By virtue of their sustained success as sources of lead compounds, natural products are recognized as "privileged" starting points in structural space for library development. Compared with synthetic compounds, natural products have distinguishing structural properties; indeed, researchers have begun to quantify and catalog the differences between the two classes of molecules. Measurable differences in the number of chiral centers, the degree of saturation, the presence of aromatic rings, and the number of the various heteroatoms are among the chief distinctions between natural and synthetic compounds. Natural products also include a significant proportion of recurring molecular scaffolds that are not present in currently marketed drugs: the bioactivity of these natural substructures has been refined over the long process of evolution. In this Account, we present our research aimed at preparing libraries of semisynthetic compounds, or chemically engineered extracts (CEEs), through chemical diversification of natural products mixtures. The approach relies on the power of numbers, that is, in the chemical alteration of a sizable fraction of the starting complex mixture. Major changes in composition can be achieved through the chemical transformation of reactive molecular fragments that are found in most natural products. If such fragments are common enough, their transformation represents an entry point for chemically altering a high proportion of the components of crude natural extracts. We have searched for common reactive fragments in the Dictionary of Natural Products (CRC Press) and identified several functional groups that are expected to be present in a large fraction of the components of an average natural crude extract. To date, we have used reactions that incorporate (i) nitrogen atoms through carbonyl groups, (ii

  4. Bioactive molecules: current trends in discovery, synthesis, delivery and testing

    Directory of Open Access Journals (Sweden)

    Yew Beng Kang

    2013-04-01

    Full Text Available Important bioactive molecules are moleculesthat are pharmacologically active derived from naturalsources and through chemical synthesis. Over the yearsmany of such molecules have been discovered throughbioprospective endeavours. The discovery of taxol fromthe pacific yew tree bark that has the ability in stabilisingcellular microtubules represents one of the hallmarks ofsuccess of such endeavours. In recent years, the discoveryprocess has been aided by the rapid developmentof techniques and technologies in chemistry andbiotechnology. The progress in advanced genetics andcomputational biology has also transformed the wayhypotheses are formulated as well as the strategies for drugdiscovery. Of equal importance is the use of advanceddrug delivery vehicles in enhancing the efficacy andbioavailability of bioactive molecules. The availability ofsuitable animal models for testing and validation is yetanother major determinant in increasing the prospect forclinical trials of bioactive molecules.

  5. PREPARATION OF BIOACTIVE NANOSTRUCTURE SCAFFOLD WITH IMPROVED COMPRESSIVE STRENGTH

    Directory of Open Access Journals (Sweden)

    R. EMADI

    2011-03-01

    Full Text Available Highly porous scaffolds with open structure are today the best candidates for bone substitution to ensure bone oxygenation and angiogenesis. In this study, we developed a new route to enhance the compressive strength of porous hydroxyapatite scaffold made of natural bone. Briefly, the spongy bone of an adult bovine was extracted, annealed, and coated by a nanostructure bioactive glass layer to be subsequently sintered at different temperatures. The apatite formation ability on the surfaces of the coated scaffolds was investigated by standard procedures. Our results showed that the scaffold and coating microstructure consisted of the grains smaller than 100 nm. These nanostructures improved the compressive strength and bioactivity of highly porous scaffold. The results showed that with increasing the sintering temperature, the compressive strength of scaffolds increased while their in vitro bioactivity decreased.

  6. Bioactive Compounds and Antioxidant Activity in Different Types of Berries

    Directory of Open Access Journals (Sweden)

    Sona Skrovankova

    2015-10-01

    Full Text Available Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry, and Ericaceae (blueberry, cranberry, belong to the best dietary sources of bioactive compounds (BAC. They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits.

  7. Edible berries: bioactive components and their effect on human health.

    Science.gov (United States)

    Nile, Shivraj Hariram; Park, Se Won

    2014-02-01

    The importance of food consumption in relation to human health has increased consumer attention in nutraceutical components and foods, especially fruits and vegetables. Berries are a rich source of a wide variety of non-nutritive, nutritive, and bioactive compounds such as flavonoids, phenolics, anthocyanins, phenolic acids, stilbenes, and tannins, as well as nutritive compounds such as sugars, essential oils, carotenoids, vitamins, and minerals. Bioactive compounds from berries have potent antioxidant, anticancer, antimutagenic, antimicrobial, anti-inflammatory, and antineurodegenerative properties, both in vitro and in vivo. The following is a comprehensive and critical review on nutritional and non-nutritional bioactive compounds of berries including their absorption, metabolism, and biological activity in relation to their potential effect on human health. PMID:24012283

  8. Bioactive benzopyrone derivatives from new recombinant fusant of marine Streptomyces.

    Science.gov (United States)

    El-Gendy, Mervat M A; Shaaban, M; El-Bondkly, A M; Shaaban, K A

    2008-07-01

    In our searching program for bioactive secondary metabolites from marine Streptomycetes, three microbial benzopyrone derivatives (1-3), 7-methylcoumarin (1) and two flavonoides, rhamnazin (2) and cirsimaritin (3), were obtained during the working up of the ethyl acetate fraction of a marine Streptomyces fusant obtained from protoplast fusion between Streptomyces strains Merv 1996 and Merv 7409. The structures of the three compounds (1-3) were established by nuclear magnetic resonance, mass, UV spectra, and by comparison with literature data. Marine Streptomyces strains were identified based on their phenotypic and chemotypic characteristics as two different bioactive strains of the genus Streptomyces. We described here the fermentation, isolation, as well as the biological activity of these bioactive compounds. The isolated compounds (1-3) are reported here as microbial products for the first time. PMID:18551256

  9. Bioactive lipids as modulators of immunity, inflammation and emotions.

    Science.gov (United States)

    Chiurchiù, Valerio; Maccarrone, Mauro

    2016-08-01

    Lipids are not only constituents of cellular membranes but also key signaling mediators, thus acting as 'bioactive lipids'. Among the prominent roles exerted by bioactive lipids are immune regulation, inflammation and maintenance of homeostasis. Accumulated evidence indicates the existence of a bidirectional relationship between immune and nervous systems, whereby inflammatory mediators can directly modulate emotions that, in turn, can strongly influence immune responses, thus affecting health. This review summarizes current knowledge on the ability of several families of bioactive lipids to regulate immunity and inflammation (through pro-inflammatory or anti-inflammatory effects), as well as to control emotions and mood-related manifestations, advocating these substances as an attractive interface between 'mind' and 'body', and as a potential target to treat inflammatory/immune-mediated mood disorders. PMID:27372887

  10. Bioactive Compounds and Antioxidant Activity in Different Types of Berries.

    Science.gov (United States)

    Skrovankova, Sona; Sumczynski, Daniela; Mlcek, Jiri; Jurikova, Tunde; Sochor, Jiri

    2015-01-01

    Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry), and Ericaceae (blueberry, cranberry), belong to the best dietary sources of bioactive compounds (BAC). They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins) and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits. PMID:26501271

  11. Bioactivity of calcium phosphate bioceramic coating fabricated by laser cladding

    Science.gov (United States)

    Zhu, Yizhi; Liu, Qibin; Xu, Peng; Li, Long; Jiang, Haibing; Bai, Yang

    2016-05-01

    There were always strong expectations for suitable biomaterials used for bone regeneration. In this study, to improve the biocompatiblity of titanium alloy, calcium phosphate bioceramic coating was obtained by laser cladding technology. The microstructure, phases, bioactivity, cell differentiation, morphology and resorption lacunae were investigated by optical microscope (OM), x-ray diffraction (XRD), methyl thiazolyl tetrazolium (MTT) assay, tartrate-resistant acid phosphatase (TRAP) staining and scanning electronic microscope (SEM), respectively. The results show that bioceramic coating consists of three layers, which are a substrate, an alloyed layer and a ceramic layer. Bioactive phases of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) were found in ceramic coating. Osteoclast precursors have excellent proliferation on the bioceramic surface. The bioceramics coating could be digested by osteoclasts, which led to the resorption lacunae formed on its surface. It revealed that the gradient bioceramic coating has an excellent bioactivity.

  12. Biological Impact of Bioactive Glasses and Their Dissolution Products.

    Science.gov (United States)

    Hoppe, Alexander; Boccaccini, Aldo R

    2015-01-01

    For many years, bioactive glasses (BGs) have been widely considered for bone tissue engineering applications due to their ability to bond to hard as well as soft tissue (a property termed bioactivity) and for their stimulating effects on bone formation. Ionic dissolution products released during the degradation of the BG matrix induce osteogenic gene expression leading to enhanced bone regeneration. Recently, adding bioactive metallic ions (e.g. boron, copper, cobalt, silver, zinc and strontium) to silicate (or phosphate and borate) glasses has emerged as a promising route for developing novel BG formulations with specific therapeutic functionalities, including antibacterial, angiogenic and osteogenic properties. The degradation behaviour of BGs can be tailored by adjusting the glass chemistry making these glass matrices potential carrier systems for controlled therapeutic ion release. This book chapter summarises the fundamental aspects of the effect of ionic dissolution products from BGs on osteogenesis and angiogenesis, whilst discussing novel BG compositions with controlled therapeutic ion release. PMID:26201273

  13. In vitro bioactivity and cytocompatibility of tricalcium silicate

    Indian Academy of Sciences (India)

    Xiaoming Liao; Hongyang Zhu; Guangfu Yin; Zhongbing Huang; Yadong Yao; Xianchun Chen

    2011-08-01

    The in vitro bioactivity of tricalcium silicate (Ca3SiO5) ceramics was investigated by the bone-like apatite-formation ability in simulated body fluid (SBF), and the cytocompatibility was evaluated through osteoblast adhesion and proliferation assay. The results show that the Ca3SiO5 ceramics possess bone-like apatite formation ability in SBF. In vitro cytocompatible evaluation reveals that osteoblasts adhere and spread well on the Ca3SiO5 ceramics, indicating good bioactivity and cytocompatibility.

  14. Bioactivities and Health Benefits of Mushrooms Mainly from China.

    Science.gov (United States)

    Zhang, Jiao-Jiao; Li, Ya; Zhou, Tong; Xu, Dong-Ping; Zhang, Pei; Li, Sha; Li, Hua-Bin

    2016-01-01

    Many mushrooms have been used as foods and medicines for a long time. Mushrooms contain polyphenols, polysaccharides, vitamins and minerals. Studies show that mushrooms possess various bioactivities, such as antioxidant, anti-inflammatory, anticancer, immunomodulatory, antimicrobial, hepatoprotective, and antidiabetic properties, therefore, mushrooms have attracted increasing attention in recent years, and could be developed into functional food or medicines for prevention and treatment of several chronic diseases, such as cancer, cardiovascular diseases, diabetes mellitus and neurodegenerative diseases. The present review summarizes the bioactivities and health benefits of mushrooms, and could be useful for full utilization of mushrooms. PMID:27447602

  15. Food-Derived Bioactive Peptides on Inflammation and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Subhadeep Chakrabarti

    2014-01-01

    Full Text Available Chronic diseases such as atherosclerosis and cancer are now the leading causes of morbidity and mortality worldwide. Inflammatory processes and oxidative stress underlie the pathogenesis of these pathological conditions. Bioactive peptides derived from food proteins have been evaluated for various beneficial effects, including anti-inflammatory and antioxidant properties. In this review, we summarize the roles of various food-derived bioactive peptides in inflammation and oxidative stress and discuss the potential benefits and limitations of using these compounds against the burden of chronic diseases.

  16. Corrosion protection of mesoporous bioactive glass coating on biodegradable magnesium

    Science.gov (United States)

    Wang, Xiaojian; Wen, Cuie

    2014-06-01

    A mesoporous bioactive glass (MBG) coating was synthesized and coated on pure Mg substrate using a sol-gel dip-coating method. The MBG coating uniformly covered the Mg substrate with a thickness of ˜1.5 μm. Electrochemical and immersion tests were performed in order to investigate the biodegradation performance of Mg with and without different surface coatings in simulated body fluids (SBF) at 37 °C. Results revealed that the MBG coated Mg displayed a significantly lower biodegradation rate, in comparison with normal bioactive glass (BG) coated and uncoated Mg samples.

  17. Thermal conductivity: recent developments on insulating and new materials; La conductivite thermique: developpements recents sur les isolants et les materiaux nouveaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This workshop organized by the thermo-kinetics section of the French society of thermal engineers deals with recent developments concerning insulating, dielectric and composite materials. The seven papers presented during this workshop concern the methods and results of thermal conductivity measurements performed in these materials and the possible applications of these materials in aerospace industry (carbon foams, ceramic-based composite materials), civil engineering (glazing materials, aerogels), power electronics (dielectric thin films, ceramics), and in other industries (heat resistant and thermal insulating materials). (J.S.)

  18. Calcium phosphate phases integrated in silica/collagen nanocomposite xerogels enhance the bioactivity and ultimately manipulate the osteoblast/osteoclast ratio in a human co-culture model.

    Science.gov (United States)

    Heinemann, S; Heinemann, C; Wenisch, S; Alt, V; Worch, H; Hanke, T

    2013-01-01

    A human co-culture model of osteoblasts and osteoclasts, derived from bone marrow stromal cells and monocytes respectively, was used to characterize the influence of biomaterial modification on the bioactivity and ultimately the ratio of bone-forming to bone-resorbing cells cultivated directly on the surface. Nanocomposites of silica and collagen have been shown to function as skeletal structures in nature and were reproduced in vitro by using a sol-gel approach. The resulting xerogels exhibit a number of features that make it a valuable system for the development of innovative materials for bone substitution applications. In the present study, the incorporation of different calcium phosphate phases in silica/collagen-based gels was demonstrated to enhance the bioactivity of these samples. This ability of the biomaterial to precipitate calcium phosphate on the surface when incubated in simulated body fluids or cell culture medium is generally considered to an advantageous property for bone substitution materials. By co-cultivating human osteoblasts and osteoclasts up to 42 days on the xerogels, we demonstrate that the long-term ratio of these cell types depends on the level of bioactivity of the substrate samples. Biphasic silica/collagen xerogels exhibited comparably low bioactivity but encouraged proliferation of osteoblasts in comparison to osteoclast formation. A balanced ratio of both cell types was detected for moderately bioactive triphasic xerogels with 5% calcium phosphate. However, enhancing the bioactivity of the xerogel samples by increasing the calcium phosphate phase percentage to 20% resulted in a diminished number of osteoblasts in favor of osteoclast formation. Quantitative evaluation was carried out by biochemical methods (calcium, DNA, ALP, TRAP 5b) as well as RT-PCR (ALP, BSP II, OC, RANKL, TRAP, CALCR, VTNR, CTSK), and was supported by confocal laser scanning microscopy (cell nuclei, actin, CD68, TRAP) as well as scanning electron microscopy

  19. Facilitated receptor-recognition and enhanced bioactivity of bone morphogenetic protein-2 on magnesium-substituted hydroxyapatite surface

    Science.gov (United States)

    Huang, Baolin; Yuan, Yuan; Li, Tong; Ding, Sai; Zhang, Wenjing; Gu, Yuantong; Liu, Changsheng

    2016-04-01

    Biomaterial surface functionalized with bone morphogenetic protein-2 (BMP-2) is a promising approach to fabricating successful orthopedic implants/scaffolds. However, the bioactivity of BMP-2 on material surfaces is still far from satisfactory and the mechanism of related protein-surface interaction remains elusive. Based on the most widely used bone-implants/scaffolds material, hydroxyapatite (HAP), we developed a matrix of magnesium-substituted HAP (Mg-HAP, 2.2 at% substitution) to address these issues. Further, we investigated the adsorption dynamics, BMPRs-recruitment, and bioactivity of recombinant human BMP-2 (rhBMP-2) on the HAP and Mg-HAP surfaces. To elucidate the mechanism, molecular dynamic simulations were performed to calculate the preferred orientations, conformation changes, and cysteine-knot stabilities of adsorbed BMP-2 molecules. The results showed that rhBMP-2 on the Mg-HAP surface exhibited greater bioactivity, evidenced by more facilitated BMPRs-recognition and higher ALP activity than on the HAP surface. Moreover, molecular simulations indicated that BMP-2 favoured distinct side-on orientations on the HAP and Mg-HAP surfaces. Intriguingly, BMP-2 on the Mg-HAP surface largely preserved the active protein structure evidenced by more stable cysteine-knots than on the HAP surface. These findings explicitly clarify the mechanism of BMP-2-HAP/Mg-HAP interactions and highlight the promising application of Mg-HAP/BMP-2 matrixes in bone regeneration implants/scaffolds.

  20. Mg-Zn based composites reinforced with bioactive glass (45S5) fabricated via powder metallurgy

    Science.gov (United States)

    Ab llah, N.; Jamaludin, S. B.; Daud, Z. C.; Zaludin, M. A. F.

    2016-07-01

    Metallic implants are shifting from bio-inert to bioactive and biodegradable materials. These changes are made in order to improve the stress shielding effect and bio-compatibility and also avoid the second surgery procedure. Second surgery procedure is required if the patient experienced infection and implant loosening. An implant is predicted to be well for 15 to 20 years inside patient body. Currently, magnesium alloys are found to be the new biomaterials because of their properties close to the human bones and also able to degrade in the human body. In this work, magnesium-zinc based composites reinforced with different content (5, 15, 20 wt. %) of bioactive glass (45S5) were fabricated through powder metallurgy technique. The composites were sintered at 450˚C. Density and porosity of the composites were determined using the gas pycnometer. Microstructure of the composites was observed using an optical microscope. In-vitro bioactivity behavior was evaluated in the simulated body fluid (SBF) for 7 days. Fourier Transform Infrared (FTIR) was used to characterize the apatite forming on the samples surface. The microstructure of the composite showed that the pore segregated near the grain boundaries and bioglass clustering was observed with increasing content of bioglass. The true density of the composites increased with the increasing content of bioglass and the highest value of porosity was indicated by the Mg-Zn reinforced with 20 wt.% of bioglass. The addition of bio-glass to the Mg-Zn has also induced the formation of apatite layer after soaking in SBF solution.

  1. Effect of Ti(+4) on in vitro bioactivity and antibacterial activity of silicate glass-ceramics.

    Science.gov (United States)

    Riaz, Madeeha; Zia, Rehana; Saleemi, Farhat; Hussain, Tousif; Bashir, Farooq; Ikhram, Hafeez

    2016-12-01

    A novel glass-ceramic series in (48-x) SiO2-36 CaO-4 P2O5-12 Na2O-xTiO2 (where x=0, 3.5, 7, 10.5 and 14mol %) system was synthesized by crystallization of glass powders, obtained by melt quenching technique. The differential scanning calorimetric analysis (DSC) was used to study the non-isothermal crystallization kinetics of the as prepared glasses. The crystallization behaviour of glasses was analyzed under non-isothermal conditions, and qualitative phase analysis of glass-ceramics was made by X-ray diffraction. The in vitro bioactivity of synthesized glass-ceramics was studied in stimulated body fluid at 37°C under static condition for 24days. The formation of hydroxyl-carbonated apatite layer; evident of bioactivity of the material, was elucidated by XRD, FTIR, AAS, SEM and EDX analysis. The result showed that partial substitution of TiO2 with SiO2 negatively influenced bioactivity; it decreased with increase in concentration of TiO2. As Ti(+4) having stronger field strength as compared to Si(+4) so its replacement became the cause for reduction in degradation that in turn improved the chemical stability. The compressive strength was also enhanced with progress addition of TiO2 in the system. The antibacterial properties were examined against Staphylococcus Epidermidis. Strong antibacterial efficacy was observed with the addition of TiO2 in the system. PMID:27612803

  2. The effect of polymer dots on bioactivity of mouse sperm in vitro

    Science.gov (United States)

    Feng, Gang; Chen, Qiang; Zhai, Peng; Wang, Xiaomei; Lin, Guimiao; Xu, Gaixia; Chen, Danni

    2014-09-01

    Objective: In recent years, semiconducting polymer dots (Pdots)have caught considerable attention for their outstanding optical characteristics in biomedical imaging applications. Not as semiconductor quantum dots, Pdots are composed of nonmetallic material and their biological effects remain unclear. In this work, we investigated the effects of a band new polymer dots on bioactivity of mouse sperm using a computer-aided sperm analysis system(CASA) and an in vitro fertilization (IVF) model. Methods: The semiconducting polymer dots used in this study is CN-PPV Pdots, which emits in the orange wavelength range with high brightness. Epididymal mouse sperm were collected from 7-8weeks old Balb/c mouse. Firstly, CN-PPV Pdots was added into the Human Tubal Fluid (HTF) media at various concentrations (0, 1, 10, 100 nmol/L respectively ), then sperm bioactivity and vitality were evaluated every 10 minutes. Secondly, the treated sperm were co-cultured with matured oocytes in HTF media, fertilization rate and oocytes development were recorded after 24 hours co-incubation. Results: Sperm viability in the control group (0 nmol/L) and experimental group (1, 10,100 nmol/L) were 57.20+/-4.51%, 58.17+/-4.81%, 55.50+/-4.52%, 46.26%+/-3.83%, respectively. Fertilization rate in different groups showed no obvious differences, control group (0 nmol/L) and experimental group (1, 10, 100 nmol/L) were 38.75+/-1.71%, 37.01+/-4.69%, 32.75+/-1.71%, 35.24+/-2.37%, respectively. Conclusion: Our data indicated that the CN-PPV Pdots had a very high biocompatibility on sperm in both the activation and the IVF process, even in extreme high Pdots concentration,the sperm bioactivity only got slight restrained. The effect of CN-PPV Pdots seems has no or little toxicity,and the long-term embryonic development has yet to be verified.

  3. Preparation of Nanofibrous Structure of Mesoporous Bioactive Glass Microbeads for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Shiao-Wen Tsai

    2016-06-01

    Full Text Available A highly ordered, mesoporous (pore size 2~50 nm bioactive glass (MBG structure has a greater surface area and pore volume and excellent bone-forming bioactivity compared with traditional bioactive glasses (BGs. Hence, MBGs have been used in drug delivery and bone tissue engineering. MBGs can be developed as either a dense or porous block. Compared with a block, microbeads provide greater flexibility for filling different-shaped cavities and are suitable for culturing cells in vitro. In contrast, the fibrous structure of a scaffold has been shown to increase cell attachment and differentiation due to its ability to mimic the three-dimensional structure of natural extracellular matrices. Hence, the aim of this study is to fabricate MBG microbeads with a fibrous structure. First, a sol-gel/electrospinning technique was utilized to fabricate the MBG nanofiber (MBGNF structure. Subsequently, the MBGNF microbeads (MFBs were produced by an electrospraying technology. The results show that the diameter of the MFBs decreases when the applied voltage increases. The drug loading and release profiles and mechanisms of the MFBs were also evaluated. MFBs had a better drug entrapment efficiency, could reduce the burst release of tetracycline, and sustain the release over 10 days. Hence, the MFBs may be suitable drug carriers. In addition, the cellular attachment of MG63 osteoblast-like cells is significantly higher for MFBs than for glass microbeads after culturing for 4 h. The nanofibrous structure of MFBs could provide an appropriate environment for cellular spreading. Therefore, MFBs have great potential for use as a bone graft material in bone tissue engineering applications.

  4. Gallium-containing phospho‐silicate glasses: Synthesis and in vitro bioactivity

    International Nuclear Information System (INIS)

    A series of Ga-containing phospho-silicate glasses based on Bioglass 45S5, having molar formula 46.2SiO2·24.3Na2O·26.9CaO·2.6P2O5·xGa2O3 (x = 1.0, 1.6, 3.5), were prepared by fusion method. The reference Bioglass 45S5 without gallium was also prepared. The synthesized glasses were immersed in simulated body fluid (SBF) for 30 days in order to observe ion release and hydroxyapatite (HA) formation. All Ga-containing glasses maintain the ability of HA formation as indicated by main X-ray diffractometric peaks and/or electronic scanning microscopy results. HA layer was formed after 1 day of SBF soaking in 45S5 glass containing up to 1.6% Ga2O3 content. Moreover, gallium released by the glasses was found to be partially precipitated on the glass surface as gallium phosphate. Further increase in gallium content reduced the ion release in SBF. The maximum of Ga3+ concentration measured in solution is ∼ 6 ppm determined for 3.5% Ga2O3 content. This amount is about half of the toxic level (14 ppm) of gallium and the glasses release gallium till 30 days of immersion in SBF. Considering the above results, the studied materials can be proposed as bioactive glasses with additional antimicrobial effect of gallium having no toxic outcome. - Highlights: ► A new class of potential bioactive glasses gallium content. ► Controlled ions release from the glass surface. ► Effect of Ga2O3 content on bioactivity (hydroxyapatite formation). ► Formation of calcite when the phosphate concentration is low in SBF.

  5. Adhesive strength of bioactive oxide layers fabricated on TNTZ alloy by three different alkali-solution treatments.

    Science.gov (United States)

    Takematsu, E; Cho, K; Hieda, J; Nakai, M; Katsumata, K; Okada, K; Niinomi, M; Matsushita, N

    2016-08-01

    Bioactive oxide layers were fabricated on Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) by three different alkali solution treatments: hydrothermal (H), electrochemical (E), and hydrothermal-electrochemical (HE). The adhesive strength of the oxide layer to the TNTZ substrate was measured to determine whether this process achieves sufficient adhesive strength for implant materials. Samples subjected to the HE process, in which a current of 15mA/cm(2) was applied at 90°C for 1h (HE90-1h), exhibited a comparatively higher adhesive strength of approximately 18MPa while still maintaining a sufficiently high bioactivity. Based on these results, an oxide layer fabricated on TNTZ by HE90-1h is considered appropriate for practical biomaterial application, though thicker oxide layers with many cracks can lead to a reduced adhesive strength. PMID:26866453

  6. Investigation of the bioactivity and biocompatibility of different glass interfaces with hydroxyapatite, fluorohydroxyapatite and 58S bioactive glass.

    Science.gov (United States)

    Han, Yuling Jamie; Loo, Say Chye Joachim; Lee, Joel; Ma, Jan

    2007-01-01

    The current review investigates the bioactivity of different glass interfaces created on thin glass cover slips as substrates. The interfaces studied are plain glass, functionalized glass using 0.5 M and 5 M of sodium hydroxide (NaOH) for 24 hrs, and glass coated with bioactive 58S Bioglass (58S). A biomimetic method, involving the exposure of the three interfaces to 1.5 times simulated body fluid (SBF) tests the bioactivity of the interfaces via creation of layer of Hydroxyapatite (HA). Fluorinated SBF will precipitate fluorine doped HA (FHA) on a bioactive interface. Higher concentration of 1.5 times of SBF used in this study intended to accelerate the formation of HA and FHA layer over the substrate. HA and FHA is found to be precipitated on the thinly coated 58S. This paper, study also the thin film coatings of three forms of bioceramics - bioactive 58S, HA and FHA. The study, also proposes to draw a relation between the morphology of HA particles with duration of exposure to SBF, the effects of fluorine on the morphology and the cell interaction with bioactive 58S, HA and FHA interfaces using pre-differentiated osteoblastic MC3T3 cells. The analysis of cells in this study is confined to three parameters that include the attachment, proliferation and viability of cells. Tests employed for the analysis of the thin film coating of HA and FHA is restricted to qualitative X-Ray Diffraction and quantitative Field Emission Scanning Electron Microscope. Other mechanical tests such as shear test are not used to test the mechanical properties of this thin layer, due to the fact that the thin film is too thin for such analysis. PMID:18607070

  7. Bioactivity of Neem (Azadirachta indica) callus extract

    International Nuclear Information System (INIS)

    This study was conducted in order to explore the possibility of utilizing plant tissue culture techniques for production of secondary metabolites from callus culture of Azadirachta indica (Neem) and to investigate the bioactivity of the established callus extract in comparison with the extract from the intact leaves. The presence of secondary metabolites in the extracts was detected by Thin Layer Chromatography (TLC). Both the callus and leaf extracts eluted five fraction of compounds and it were observed that callus extract had a good resolution. various extract concentration (5.10. and 20 mg/ml) were determined for the rate and extent of inhibition kinetics against staphylococcus aureus. Escherichia coli, and candida albicans. Results showed that callus extract of A. indica wiped out all viable cells of C. albicans within 18 hours and the subsequent concentration 5 and 10 mg/ m1 retard the growth after 24 h. A higher concentration of 20 mg/ ml had the same effect on S. aureus after 6 h and the E. coli cells were completely inhibited by the extracts after 24 h. Similar kinetics were showed by leaf extract but in slight rate as compared to the callus extract. In general both extract posses antimicrobial activity with notable efficient rates. For assaying of the inhibitory effect on some phyto pathogens the effect of different concentrations of the callus and leaf extracts on the radial growth of Drechslera rostrata. Fusarium oxysporum and Alterneria alternata were in vitro assessed. Obvious inhibitory effect was observed on the mycelia radial growth of the three treated fungi. The level of inhibition increased with the increase of te extract concentration. The maximum inhibitory effect (84%) was recorded with Drechslera rostrata when inoculated in media contain 20 mg/ ml of callus while the inhibition rate of mycelia growth of the same species reaches 61% when inoculated in a medium contain the same concentration of the neem leaf extract. The subsequent

  8. Traceability of Functional Bioactive Compounds in Fresh and Pasteurized Milk Obtained from Goats Fed with Orange Pulp

    Directory of Open Access Journals (Sweden)

    Maria Simona Chiş

    2015-11-01

    Full Text Available Traceability is the ability to identify and trace the history, distribution, location, and application of products, parts, and materials. A traceability system records and follows the trail as products, parts, and materials come from suppliers and are processed and ultimately distributed as end products (Prache et al, 2002. In this work, were studied the bioactive compounds (total vitamin C, ascorbic acid, total phenols, flavonoids, carotenoids, vitamin A and vitamin E and antioxidant activity of goat fresh milk and pasteurized one. The goats were fed with a standard diet (control diet and then with a diet that incorporates orange pulp. The control diet (CD corresponded with a standard ration (a ration wich provide the energetic and proteic values, daily food for milking animals. From that ration, the Department of Animal Science, from Politechnic University of Valencia replaced the different proportions of the ingredients for incorporating orange pulp diet (OPD. The results of the present study show that the citrus pulp silage mixture used can be fed to goats without any negative effects on the performance of the animals. Results of this study indicate that citrus pulp silage can replace part of the conventional ration of goats, thus lowering the cost of production. The first aim of this study was to compare the two types of goat diets: a standard diet and a diet with orange pulp, by analyzing the bioactive compounds in fresh and pasteurized milk. The results demonstrate that all the bioactive compounds are bigger in the orange pulp diet than in the control diet. The second objective of this study was to analyze the bioavailability and traceability of bioactive compounds in fresh milk. 

  9. Electrochemistry and Spectroelectrochemistry of Bioactive Hydroxyquinolines: A Mechanistic Study

    Czech Academy of Sciences Publication Activity Database

    Sokolová, Romana; Nycz, J. E.; Ramešová, Šárka; Fiedler, Jan; Degano, I.; Szala, M.; Kolivoška, Viliam; Gál, M.

    2015-01-01

    Roč. 119, č. 20 (2015), s. 6074-6080. ISSN 1520-6106 Grant ostatní: Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR M200401201 Institutional support: RVO:61388955 Keywords : electrochemistry * spectroelectrochemistry * Bioactive Hydroxyquinolines Subject RIV: CG - Electrochemistry Impact factor: 3.302, year: 2014

  10. The bioactivity mechanism of magnetron sputtered bioglass thin films

    Energy Technology Data Exchange (ETDEWEB)

    Berbecaru, C. [University of Bucharest, Faculty of Physics, Bucharest 077125 (Romania); Stan, G.E., E-mail: george_stan@infim.ro [National Institute of Materials Physics, P.O. Box MG-7, Bucharest-Magurele 077125 (Romania); Pina, S. [Department of Ceramics and Glass Engineering, CICECO, University of Aveiro, Aveiro 3810-193 (Portugal); Tulyaganov, D.U. [Department of Ceramics and Glass Engineering, CICECO, University of Aveiro, Aveiro 3810-193 (Portugal); Turin Polytechnic University in Tashkent, 700095 Tashkent (Uzbekistan); Ferreira, J.M.F. [Department of Ceramics and Glass Engineering, CICECO, University of Aveiro, Aveiro 3810-193 (Portugal)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer RF-sputtering: an efficient solution for synthesizing bioactive glass thin films. Black-Right-Pointing-Pointer Electrostatic interactions between charged surface and ions from stagnant solution. Black-Right-Pointing-Pointer Heterogeneous-type nucleation of apatite from the SBF solution on the glass surface. Black-Right-Pointing-Pointer Peculiarities of hydroxyapatite nucleation process and biomineralisation kinetics. - Abstract: Smooth and adherent bioactive coatings with {approx}0.5 {mu}m thickness were deposited onto Si substrates by the radiofrequency-magnetron sputtering method at 150 Degree-Sign C under 0.4 Pa of Ar atmosphere using a bioglass powder as target with a composition in the SiO{sub 2}-CaO-MgO-P{sub 2}O{sub 5}-CaF{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O system. The bioactivity of the as-prepared bioglass samples was assessed by immersion in simulated body fluid for different periods of time up to 30 days. Grazing incidence X-ray diffraction, Fourier transform infra-red spectrometry and energy dispersive spectroscopy revealed that important structural and compositional changes took place upon immersing the samples in SBF. Whilst the excellent biomineralisation capability of the BG thin films was demonstrated by the in vitro induction of extensive and homogenous crystalline hydroxyapatite in-growths on their surfaces, a series of bioactivity process kinetics peculiarities (derogations from the classical model) were emphasised and thoroughly discussed.

  11. Synthesis, characterization, and bioactivity of rosin quaternary ammonium salt derivatives

    Directory of Open Access Journals (Sweden)

    Tao Liang

    2013-02-01

    Full Text Available Two series of rosin quaternary ammonium salts (QAS were synthesized using the same path. The structure of the target products was characterized by HPLC, MS, IR, and 1HNMR, and the bioactivity was determined by filter paper method using Trametes versicolor (white-rot fungus and Gloeophyllum trabeum (brown-rot fungus, which are two kinds of general wood decay fungi in nature. The results showed that all compounds tested had a satisfactory anti-fungal effect at the molarity of 0.025 mmol/mL. Hereinto, acrylpimaric Gemini QAS had better bioactivity than dehydrogenated or tetrahydrogenated rosin QAS against Trametes versicolor. To this fungus, quaternary ammonium groups, which wraps up the membrane of microorganism and disrupts the balance in cell membrane, plays the leading role for its bioactivity. To Gloeophyllum trabeum, the inhibition activity of acrylpimaric QAS and dehydrogenated rosin QAS are almost at the same level and larger than tetrahydrogenated rosin QAS, so we conclude that both quaternary ammonium group and aromatic group play important roles. Compared with dodecyl dimethyl benzyl ammonium chloride (1227, which is a commercially available quaternary ammonium salt type fungicide, acrylpimaric acid quaternary ammonium salts have approximate bioactivity against Gloeophyllum trabeum. In conclusion, rosin derivatives with functional groups would do well in wood preservative applications.

  12. Advancement into the Arctic Region for Bioactive Sponge Secondary Metabolites

    Directory of Open Access Journals (Sweden)

    Mark Hamann

    2011-11-01

    Full Text Available Porifera have long been a reservoir for the discovery of bioactive compounds and drug discovery. Most research in the area has focused on sponges from tropical and temperate waters, but more recently the focus has shifted to the less accessible colder waters of the Antarctic and, to a lesser extent, the Arctic. The Antarctic region in particular has been a more popular location for natural products discovery and has provided promising candidates for drug development. This article reviews groups of bioactive compounds that have been isolated and reported from the southern reaches of the Arctic Circle, surveys the known sponge diversity present in the Arctic waters, and details a recent sponge collection by our group in the Aleutian Islands, Alaska. The collection has yielded previously undescribed sponge species along with primary activity against opportunistic infectious diseases, malaria, and HCV. The discovery of new sponge species and bioactive crude extracts gives optimism for the isolation of new bioactive compounds from a relatively unexplored source.

  13. Case studies of the synthesis of bioactive cyclodepsipeptide natural products

    OpenAIRE

    Markus Kaiser; Stolze, Sara C.

    2013-01-01

    Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of a suitable macrocyclization methodology. This review therefore compiles case studies of synthetic approaches to different bioactive cyclod...

  14. Bioactivities and Health Benefits of Mushrooms Mainly from China

    OpenAIRE

    Jiao-Jiao Zhang; Ya Li; Tong Zhou; Dong-Ping Xu; Pei Zhang; Sha Li; Hua-Bin Li

    2016-01-01

    Many mushrooms have been used as foods and medicines for a long time. Mushrooms contain polyphenols, polysaccharides, vitamins and minerals. Studies show that mushrooms possess various bioactivities, such as antioxidant, anti-inflammatory, anticancer, immunomodulatory, antimicrobial, hepatoprotective, and antidiabetic properties, therefore, mushrooms have attracted increasing attention in recent years, and could be developed into functional food or medicines for prevention and treatment of se...

  15. Chitosan/bioactive glass nanoparticle composite membranes for periodontal regeneration

    NARCIS (Netherlands)

    Mota, J.; Yu, N.; Caridade, S.G.; Luz, G.M.; Gomes, M.E.R.; Reis, R.L.; Jansen, J.A.; Walboomers, X.F.; Mano, J.F.

    2012-01-01

    Barrier membranes are used in periodontal applications with the aim of supporting periodontal regeneration by physically blocking migration of epithelial cells. The present work proposes a combination of chitosan (CHT) with bioactive glass nanoparticles (BG-NPs) in order to produce a novel guided ti

  16. Bioactive Natural Products From Chinese Tropical Marine Organisms

    Institute of Scientific and Technical Information of China (English)

    GUO,Yue-Wei

    2004-01-01

    @@ The oceans contain a vast biological diversity of species that have so far been utilized by mankind mainly as a source of protein. In the last few decades, however, natural products chemists have started to discover the wealth of bioactive secondary metabolites that are produced by marine invertebrates such as sponges, soft corals, molluscs and others.

  17. Phenolic waste valorization through bioenergy and bioactive compounds production [Resumo

    OpenAIRE

    Marques, Isabel Paula Ramos; Morana, A; La Cara, F.

    2014-01-01

    The agricultural and industrial processing activities produce large amounts of waste that are only partially valorised at different value-added levels (spread on land, animal feed, composting), whereas the main volumes are managed as waste of environmental worry. These by-products are rich sources of bioactive compounds, including phenolic compounds with high antioxidant activity.

  18. Dereplication of phorbol bioactives: Lyngbya majuscula and Croton cuneatus

    Energy Technology Data Exchange (ETDEWEB)

    Beutler, J.A.; Alvarado, A.B.; Schaufelberger, D.E.; Andrews, P.; McCloud, T.G. (Developmental Therapeutics Program, National Cancer Institute, Frederick, Maryland (USA))

    1990-07-01

    Lyngbya majuscula and Croton cuneatus were used as prototypes for the dereplication of phorbol ester receptor binding activity using a combination of hplc-uv and online phorbol dibutyrate (PDBu) receptor binding and batch fractionation over either Si gel or diolbonded Si gel. Debromoaplysiatoxin was responsible for the bioactivity of Lyngbya, whereas a complex of potent phorbol esters was detected in C. cuneatus.

  19. New bioactive and biobased product applications of pectin

    Science.gov (United States)

    Pectin is well known for its bioactive health-promoting properties and use in biobased products. Recent reports have demonstrated that pectin and pectic fractions have potential as prebiotics, prevent pathogenic bacterial adhesion, increase prostate specific antigen doubling time in patients with re...

  20. Plastids of Marine Phytoplankton Produce Bioactive Pigments and Lipids

    Directory of Open Access Journals (Sweden)

    Benoît Schoefs

    2013-09-01

    Full Text Available Phytoplankton is acknowledged to be a very diverse source of bioactive molecules. These compounds play physiological roles that allow cells to deal with changes of the environmental constrains. For example, the diversity of light harvesting pigments allows efficient photosynthesis at different depths in the seawater column. Identically, lipid composition of cell membranes can vary according to environmental factors. This, together with the heterogenous evolutionary origin of taxa, makes the chemical diversity of phytoplankton compounds much larger than in terrestrial plants. This contribution is dedicated to pigments and lipids synthesized within or from plastids/photosynthetic membranes. It starts with a short review of cyanobacteria and microalgae phylogeny. Then the bioactivity of pigments and lipids (anti-oxidant, anti-inflammatory, anti-mutagenic, anti-cancer, anti-obesity, anti-allergic activities, and cardio- neuro-, hepato- and photoprotective effects, alone or in combination, is detailed. To increase the cellular production of bioactive compounds, specific culture conditions may be applied (e.g., high light intensity, nitrogen starvation. Regardless of the progress made in blue biotechnologies, the production of bioactive compounds is still limited. However, some examples of large scale production are given, and perspectives are suggested in the final section.

  1. A novel graded bioactive high adhesion implant coating

    International Nuclear Information System (INIS)

    One method to increase the clinical success rate of metal implants is to increase their bone bonding properties, i.e. to develop a bone bioactive surface leading to reduced risks of interfacial problems. Much research has been devoted to modifying the surface of metals to make them become bioactive. Many of the proposed methods include depositing a coating on the implant. However, there is a risk of coating failure due to low substrate adhesion. This paper describes a method to obtain bioactivity combined with a high coating adhesion via a gradient structure of the coating. Gradient coatings were deposited on Ti (grade 5) using reactive magnetron sputtering with increasing oxygen content. To increase the grain size in the coating, all coatings were post annealed at 385 deg. C. The obtained coating exhibited a gradual transition over 70 nm from crystalline titanium oxide (anatase) at the surface to metallic Ti in the substrate, as shown using cross-section transmission electron microscopy and X-ray photoelectron spectroscopy depth profiling. Using scratch testing, it could be shown that the adhesion to the substrate was well above 1 GPa. The bioactivity of the coating was verified in vitro by the spontaneous formation of hydroxylapatite upon storage in phosphate buffer solution at 37 deg. C for one week. The described process can be applied to implants irrespective of bulk metal in the base and should introduce the possibility to create safer permanent implants like reconstructive devices, dental, or spinal implants.

  2. Greener and Expeditious Synthesis of Bioactive Heterocycles using Microwave Irradiation

    Science.gov (United States)

    The utilization of green chemistry techniques is dramatically reducing chemical waste and reaction times as has recently been proven in several organic syntheses and chemical transformations. To illustrate these advantages in the synthesis of bio-active heterocycles, we have stud...

  3. Excipient Nanoemulsions for Improving Oral Bioavailability of Bioactives

    Directory of Open Access Journals (Sweden)

    Laura Salvia-Trujillo

    2016-01-01

    Full Text Available The oral bioavailability of many hydrophobic bioactive compounds found in natural food products (such as vitamins and nutraceuticals in fruits and vegetables is relatively low due to their low bioaccessibility, chemical instability, or poor absorption. Most previous research has therefore focused on the design of delivery systems to incorporate isolated bioactive compounds into food products. However, a more sustainable and cost-effect approach to enhancing the functionality of bioactive compounds is to leave them within their natural environment, but specifically design excipient foods that enhance their bioavailability. Excipient foods typically do not have functionality themselves but they have the capacity to enhance the functionality of nutrients present in natural foods by altering their bioaccessibility, absorption, and/or chemical transformation. In this review article we present the use of excipient nanoemulsions for increasing the bioavailability of bioactive components from fruits and vegetables. Nanoemulsions present several advantages over other food systems for this application, such as the ability to incorporate hydrophilic, amphiphilic, and lipophilic excipient ingredients, high physical stability, and rapid gastrointestinal digestibility. The design, fabrication, and application of nanoemulsions as excipient foods will therefore be described in this article.

  4. SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF SOL–GEL DERIVED NANOMATERIAL IN THE TERNARY SYSTEM 64 % SiO2 - 31 % CaO - 5 % P2O5 AS A BIOACTIVE GLASS: IN VITRO STUDY

    Directory of Open Access Journals (Sweden)

    Bizari D.

    2013-09-01

    Full Text Available In this study, we performed a new bioactive glass formulation with the molar composition 64 % SiO2 - 31 % CaO - 5 % P2O5 by the sol-gel method. Sol-gel derived bioglass material was produced in nanopowder using planetary milling machine, followed by sintering at 700°C, for applications as bioactive material in bioactive scaffolds or in orthopaedic. The obtained material was evaluated by X-ray powder diffraction (XRD, thermal gravimetric analysis (TGA, differential scanning calorimetry (DSC analyses, Fourier transform infrared spectroscopy (FTIR, scanning electron microscope (SEM and nitrogen adsorption pore size. The biocompatibility evaluation of the formed glass was assessed through in vitro cell culture by evaluation of alkaline phosphatase activity of osteoblasts and immersion studies in simulated body fluid (SBF for different time intervals while monitoring the pH changes and the concentration of calcium, phosphorus and silicon in the SBF medium as key factors in the rapid bonding of this bioactive glass to bone tissue as a high bioactive glass. The present investigation revealed that the sol-gel derived ternary bioglass system has the ability to support the growth of human fetal osteoblastic cells (hFOB 1.19. Finally, this material proved to be non-toxic and compatible for the proposed work in segmental defects in the goat model in vivo.

  5. Study on bioactivity of NiTinol after surface treatment

    Directory of Open Access Journals (Sweden)

    W. Chrzanowski

    2008-05-01

    Full Text Available Purpose: The aim of the work was to assess bioactive properties and corrosion resistance of nickel titanium alloyafter alkali treatment and spark oxidation in Hank’s Balance Salt Solution.Design/methodology/approach: Surfaces of samples were prepared by chemical treatment in NaOHfollowed by heat treatment, and spark oxidation. Corrosion resistance was investigated using potentiodynamicmethod. Chemical composition of the samples surface was measured using SEM EDX. Surface roughness andtopography was analyzed using AFM. Bioactive properties were analyses on the basis of the chemical compositionof the samples immersed in HBSS for 14 days.Findings: The chemical composition analysis of the samples showed that alkali treatment increased significantlynickel content in top layer and also increase in roughness was observed. Spark oxidation results also in roughnessincrease. Corrosion test showed insignificant increase of the corrosion resistance after oxidation while alkalitreatment caused drop of the resistance. Bioactivity study revealed that both applied treatments did not improvebioactive properties of the NiTinol when compared with simply ground samples.Research limitations/implications: Two types of the treatment applied for nickel titanium and intended toimprove bioactive properties were investigated. There was no improvement in bioactivity observed after surfacetreatment. However, alternation in chemical composition, corrosion resistance, and topography were observed.Further analysis of biocompatibility and mechanical properties are required.Practical implications: Both chemical and electrochemical treatment, as presented in the paper, gave promisingresults in terms of wetting ability, topography and apatite film formation, however further study are required toconfirm suitability of the treatments for medical applications.Originality/value: The obtained results revealed unsuitability of the alkali treatment intended to improvebioactivity of the

  6. Osteoconductivity and mechanical properties of a new bioactive bone cement

    Energy Technology Data Exchange (ETDEWEB)

    Shinzato, S.; Nakamura, T. [Kyoto Univ. (Japan). Dept. of Orthopaedic Surgery; Kokubo, T. [Kyoto Univ. (Japan). Dept. of Material Chemistry; Kitamura, Y. (Nippon Electric Glass Co. Ltd., Otsu)

    2001-07-01

    Osteoconductivity and mechanical properties of a new bioactive bone cement (designated GBC) consisting of high molecular weight polymethyl methacrylate (PMMA) as an organic matrix and bioactive glass beads as an inorganic filler have been evaluated. The bioactive beads consisting of MgO-CaO-SiO{sub 2}-P{sub 2}O{sub 5}CaF{sub 2} glass, have been newly designed and a novel PMMA powder was selected. The aim of the present study is to compare GBC's osteoconductivity and mechanical properties with cements consisting of the same matrix as GBC and either apatite- and wollastonite-containing glass-ceramic (AW-GC) powder (designated AWC) or sintered hydroxyapatite (HA) powder (designated HAC) and to examine effects of the amount of the bioactive glass beads filler added to GBC, and to decide the most suitable amount of the filler content. The bioactive glass beads added to the cements amounted 30, 40, 50, 60, and 70 wt%, and AW-GC powder and HA powder added to the cements amounted 70 wt%. Each cement was designated respectively GBC30, 40, 50, 60, 70, AWC70, and HAC70. The bending strength of GBC70 was significantly higher than that of AWC70 and HAC70. The compressive strength and the elastic modulus of bending of GBC increased as the glass beads content increased. The handling property of each GBC was comparable with that of conventional PMMA bone cement. Cements were packed into intramedullar canals of rat tibiae in order to evaluate osteoconductivity determined by an affinity index.

  7. BIOACTIVITY OF BIORESORBABLE OSTEOSYNTHETICDEVICES MADE OF HYDROXYAPATITE/ POLY-DL- LAC- TIDE COMPOSITES: AN EXPERIMENTAL STUDY

    Institute of Scientific and Technical Information of China (English)

    郑启新; 郭晓东; 杜靖远; 刘勇

    2001-01-01

    Aim. To investigate the bioactivity of the serf-designed biodegradable osteosynthetic devices made of resorbable hydroxyapatite microparticles/ poly-DL-lactide (HA/PDLLA) composites. Method. Forty-three rabbits with a transverse transcondylar osteotomy of the distal femur were fLxed intramedullary by a HA/PDLLA rod, the duration of follow-up were 3,6,12, 24 and 36 weeks. Histological, scanning electron microscopic (SEM), energy dispersive X-ray (EDX) and biomechanical analyses were done. Resudts. Active new bone formation and direct bone-bonding were seen at the bone-implant interface. Generous apatite crystals deposited and grew on the surface of the composites at 3 - 6 weeks postoperation. The interracial shear strength increased significantly. Conclusion. Through the incorporating of resorbable HA microparticles, specific bone-bonding and active osteogenic capacity is introduced. This kind of bioactivity, together with other properties such as sufficient mechanical strength, enhanced biocompatibi]ity and mdiopacity, which are intrinsically unobtainable in totally resorbable polymer/polymer systems, make the HA/PDLLA composites become a desirable material for the internal fixation of cancellous bone.

  8. Volatile Constituents, Inorganic Elements and Primary Screening of Bioactivity of Black Coral Cigarette Holders

    Directory of Open Access Journals (Sweden)

    Ganggang Shi

    2011-05-01

    Full Text Available Black corals (BC have been used for a long time in Chinese medicine, and may have some pharmaceutical functions when used as material for cigarette holders in southeast China. This study is aimed to investigate the bioactivities of volatile constituents in BC and to explore the folklore behind the use of BC cigarette holders (BCCHs. We extracted the volatile constituents of BC by supercritical fluid extraction (SFE with carbon dioxide (CO2-SFE, then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS. In total, 15 components were reliably identified in BC and found to be biologically active. These included triethyl phosphate, butylated hydroxytoluene, cedrol, n-hexadecanoic acid, squalene, and cholesterol. Meanwhile 13 inorganic elements (P, Ca, Mg, S, B, Si, Fe, Cu, Zn, Ba, etc. were determined by inductively coupled plasma spectrometer (ICPS. In the bioactivity tests, the BC extract (BCE showed a scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radicals and hydroxyl radicals by phenanthroline-Fe (II oxidation and moderate inhibition of Gram-positive microorganisms. The antioxidant and antimicrobial activities of BC, which are related to the active chemical composition, may explain the perceived benefit for cigarette smokers who use BCCHs.

  9. Effect of alkali and heat treatments for bioactivity of TiO2 nanotubes

    Science.gov (United States)

    Kim, Seo young; Kim, Yu kyoung; Park, Il song; Jin, Guang chun; Bae, Tae sung; Lee, Min ho

    2014-12-01

    In this study, for improving the bioactivity of titanium used as an implant material, alkali and heat treatments were carried out after formation of the nanotubes via anodization. Nanotubes with uniform length, diameter, and thickness were formed by anodization. The alkali and heat-treated TiO2 nanotubes were covered with the complex network structure, and the Na compound was generated on the surface of the specimens. In addition, after 5 and 10 days of immersion in the SBF, the crystallized OCP and HAp phase was significantly increased on the surface of the alkali-treated TiO2 nanotubes (PNA) and alkali and heat-treated TiO2 nanotubes (PNAH) groups. Cell proliferation was decreased due to the formation of amorphous sodium titanate (Na2TiO3) layer on the surface of the PNA group. However, anatase and crystalline sodium titanate were formed on the surface of the PNAH group after heat treatment at 550 °C, and cell proliferation was improved. Thus, PNA group had higher HAp forming ability in the simulated body fluid. Additional heat treatment affected on enhancement of the bioactivity and the attachment of osteoblasts for PNA group.

  10. Bioactive Wollastonite-Diopside Foams from Preceramic Polymers and Reactive Oxide Fillers

    Directory of Open Access Journals (Sweden)

    Laura Fiocco

    2015-05-01

    Full Text Available Wollastonite (CaSiO3 and diopside (CaMgSi2O6 silicate ceramics have been widely investigated as highly bioactive materials, suitable for bone tissue engineering applications. In the present paper, highly porous glass-ceramic foams, with both wollastonite and diopside as crystal phases, were developed from the thermal treatment of silicone polymers filled with CaO and MgO precursors, in the form of micro-sized particles. The foaming was due to water release, at low temperature, in the polymeric matrix before ceramic conversion, mainly operated by hydrated sodium phosphate, used as a secondary filler. This additive proved to be “multifunctional”, since it additionally favored the phase development, by the formation of a liquid phase upon firing, in turn promoting the ionic interdiffusion. The liquid phase was promoted also by the incorporation of powders of a glass crystallizing itself in wollastonite and diopside, with significant improvements in both structural integrity and crushing strength. The biological characterization of polymer-derived wollastonite-diopside foams, to assess the bioactivity of the samples, was performed by means of a cell culture test. The MTT assay and LDH activity tests gave positive results in terms of cell viability.

  11. GC-MS analysis of bioactive compounds in the methanol extract of Clerodendrum viscosum leaves

    Directory of Open Access Journals (Sweden)

    Pritipadma Panda

    2015-01-01

    Full Text Available Background: Clerodendrum viscosum is commonly found in India and Bangladesh. Previously, various parts of this plant were reported for treatment of different types of diseases and there was no report on GC-Ms analysis. Objective: To analyze and characterize the phytochemical compounds of methanol extract of Clerodendrum viscosum using GC-MS. Materials and Methods: The preliminary phytochemical screening of methanol extract was carried out according to standard procedures described in WHO guidelines. Various bioactive compounds of the extract were determined by GC-MS technique. Results: The presence of steroids, triterpenoids, alkaloids, saponins, flavonoids, tannins and carbohydrate was found on phytochemical screening of methanol extract of the leaves. The GC-MS analysis showed 16 peaks of different phytoconstituents namely acetamide,N,N-carbonylbis-, 4-Pyranone,2,3-dihydro-, alpha-D-Galactofuranoside, methyl 2,3,5,6-tetra-O-methyl-, Glycerin, Xylitol, N,N-Dimethylglycine, 4H-Pyran-4-one,2,3-dihydro-3, 5-dihydroxy-6-methyl-, Benzofuran,2,3-dihydro-, 5-Hydroxymethylfurfural, 2(1HPyrimidinone,1-methyl-, 2,4-Dihydroxy-5,6-dimethylpyrimidine, 3-Deoxy-d-mannoic lactone, 1,3-Methylene-d-arabitol, Orcinol, n-Hexadecanoic acid and Phenol,4,4′-(1-methyl ethylidene bis etc. Conclusion: The bioactive compounds present in the methanol extract of Clerodendrum viscosum suggest the application of this extract for the treatment of various diseases by the aborigine tribes.

  12. EFFECT OF SINTERING TEMPERATURE ON MICROSTRUCTURE AND IN-VITRO BEHAVIOR OF BIOACTIVE GLASS-CERAMICS

    Directory of Open Access Journals (Sweden)

    Hashmi M. U.

    2013-12-01

    Full Text Available In this work, powders of the composition (CaO 46- SiO2 34- P2O5 14.5- MgO 4- CaF2 1- MgF2 0.5 (wt. % were thoroughly mixed and melted in a muffle furnace. The melt was quenched in water to form glass. Three glass-ceramics were prepared by sintering glass samples at three different temperatures 850, 900 and 950°C according to the exothermal peaks of DTA. The DTA peaks correspond to the bioactive crystalline phases hydroxyapatite (HA and wollastonite as confirmed by the XRD data. Study of diameter-shrinkage co-efficient and bulk-density of samples revealed higher densification rate for the range 900 - 950°C than that for the range 850 - 900°C.SEM and optical microscope results illustrated a tendency towards closely packed structure and increasing grain size with the increase of sintering temperature. The samples were immersed in SBF for 30 days at room temperature for in-vitro evaluation.EDS analysis, showing the presence of carbon (C along with calcium (Ca and phosphorus (P suggests the formation of hydroxycarbonate-apatite (HCA phase that indicates the bioactivity of the material which increases with the increase of sintering temperature.

  13. Synthesis and Purification of 7-Prenyloxycoumarins and Herniarin as Bioactive Natural Coumarins

    Directory of Open Access Journals (Sweden)

    Mahdi Askari, Amirhossein Sahebkar, Mehrdad Iransahi

    2009-06-01

    Full Text Available Objective(s7-prenyloxycoumarins including 7-isopentenyloxycoumarin, auraptene and umbelliprenin, and herniarinhave been widely recognized as bioactive coumarins. This paper presents the ways to synthesis thesecompounds.Materials and Methods7-prenyloxycoumarins were synthesized by reaction between 7-hydroxycoumarin (1 M and relevant prenylbromides (1.5 M in acetone at room temperature. The reaction was carried out in the presence of DBU(1, 8-diazabicyclo [5.4.0] undec-7-ene (2 M. After 24 hr, the mixture was concentrated under reducedpressure. The compounds were purified by column chromatography.ResultsThree bioactive 7-prenyloxycoumarins, namely, umbelliprenin, auraptene and 7-isopentenyloxycoumarin,together with herniarin were synthesized from 7-hydroxycoumarin under alkaline conditions (DBU and thenpurified by column chromatography. The structures of the products were characterized by NMRspectroscopic method including 1H- and 13C-NMR experiments.ConclusionThe method of synthesis for 7-prenyloxycoumarins and herniarin which is presented here has not beenreported yet. Moreover, for the first time, umbelliprenin was chemically prepared in this work.Keywords: Auraptene, Herniarin, 7- Isopentenyloxycoumarin, 7-Prenyloxycoumarins, Synthesis,Umbelliprenin

  14. Development of highly bioactive and mechanically strong starch thermoplastic/Bioglass {sup trademark} composite biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Leonor, I.B.; Sousa, R.A.; Cunha, A.M.; Reis, R.L. [Minho Univ., Braga (Portugal). Dept. of Polymer Engineering; Zhong, Z.P.; Greenspan, D. [US Biomaterials Corp., Alachua FL (United States)

    2001-07-01

    Bioglass {sup trademark} 45S5 (BG45S5), with a granulometric distribution between 38 and 53 {mu}m, was incorporated into a biodegradable starch based polymers (starch/ethylene-vinyl alcohol blends - SEVA-C) aiming to develop composites with adequate properties for bone replacement applications. Composites with 10 and 40% (by weight) of Bioglass {sup trademark} 45S5 were compound by twin-screw extrusion (TSE) and then injection moulded. SEVA-C/ hydroxylapatite (HA) composites were also produced using the same methodology for comparative purposes. The mechanical properties of the composites were evaluated in tensile tests, and their bioactivity was assessed by analysing the respective surfaces scanning electron microscopy and energy dispersive spectroscopy (SEM/EDS) after different immersion periods in a simulated body fluid (SBF). The biodegradability of the composites was also assessed. The results obtained indicated the SEVA-C/Bioglass {sup trademark} composites present a slightly higher stiffness and strength (a modulus of 3.8 GPa and UTS of 38.6 GPa) than SEVA-C/HA composites. The bioactivity of SEVA-C composites becomes relevant for BG45S5 amounts of only 10% wt. The composites were biodegradable being the results correlated with the correspondent materials compositions. (orig.)

  15. Bioactive coatings on Portland cement substrates: Surface precipitation of apatite-like crystals

    Energy Technology Data Exchange (ETDEWEB)

    Gallego, Daniel [Biomedical Engineering Department, Ohio State University, 1080 Carmack Road, 270 Bevis Hall, Columbus (OH) - 43210 (United States); Higuita, Natalia [Biomedical Engineering Department, Ohio State University, 1080 Carmack Road, 270 Bevis Hall, Columbus (OH) - 43210 (United States); Grupo de Investigacion en Ingenieria Biomedica CES-EIA (GIBEC), Carrera 43 A No. 52 Sur - 99, Sabaneta (Colombia); Garcia, Felipe [Grupo de Investigacion en Ingenieria Biomedica CES-EIA (GIBEC), Carrera 43 A No. 52 Sur - 99, Sabaneta (Colombia); Ferrell, Nicholas [Biomedical Engineering Department, Ohio State University, 1080 Carmack Road, 270 Bevis Hall, Columbus (OH) - 43210 (United States); Hansford, Derek J. [Biomedical Engineering Department, Ohio State University, 1080 Carmack Road, 270 Bevis Hall, Columbus (OH) - 43210 (United States)], E-mail: hansford.4@osu.edu

    2008-04-01

    We report a method for depositing bioactive coatings onto cement materials for bone tissue engineering applications. White Portland cement substrates were hydrated under a 20% CO{sub 2} atmosphere, allowing the formation of CaCO{sub 3}. The substrates were incubated in a calcium phosphate solution for 1, 3, and 6 days (CPI, CPII, and CPIII respectively) at 37 deg. C to induce the formation of carbonated apatite. Cement controls were prepared and hydrated with and without CO{sub 2} atmosphere (C+ and C- respectively). The presence of apatite-like crystals was verified by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The substrate cytocompatibility was evaluated via SEM after 24 hour cell cultures. SEM revealed the presence Ca(OH){sub 2} on C-, and CaCO{sub 3} on C+. Apatite-like crystals were detected only on CPIII, confirmed by phosphorus EDS peaks only for CPIII. Cells attached and proliferated similarly well on all the substrates except C-. These results prove the feasibility of obtaining biocompatible and bioactive coatings on Portland cement for bone tissue engineering applications.

  16. Extracellular matrix formation in self-assembled minimalistic bioactive hydrogels based on aromatic peptide amphiphiles.

    Science.gov (United States)

    Zhou, Mi; Ulijn, Rein V; Gough, Julie E

    2014-01-01

    The hitherto inconsistency in clinical performance for engineered skin drives the current development of novel cell-scaffolding materials; one challenge is to only extract essential characteristics from the complex native ECM (extracellular matrix) and incorporate them into a scaffold with minimal complexity to support normal cell functions. This study involved small-molecule-based bioactive hydrogels produced by the co-assembly of two aromatic peptide amphiphiles: Fmoc-FF (Fluorenylmethoxycarbonyl-diphenylalanine) and Fmoc-RGD (arginine-glycine-aspartic acid). Three-dimensionally cultured human dermal fibroblasts deposited dense ECM networks including fibronectin and collagen I within the hydrogels in a 14-day culture. The fibroblasts organized the fibrous ECM and contracted the gel without differentiating into myofibroblasts. The stiffness of the cell-gel constructs increased dramatically due to ECM formation and gel contraction. This created an economical biomimetic model-scaffold to further understand skin reconstruction in vitro and supplied a design pathway to create versatile cell-scaffolds with varied bioactivities and simplicity. PMID:24812581

  17. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyun Suk; Ko, Yeong Mu; Shim, Jae Won [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of); Lim, Yun Kyong; Kook, Joong-Ki [Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Cho, Dong-Lyun [School of Applied Chemical Engineering and Center for Functional Nano Fine Chemicals, Chonnam National University, Gwangju (Korea, Republic of); Kim, Byung Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, MRC Center, Chosun University, Gwangju (Korea, Republic of)

    2010-11-01

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH{sub 2} of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  18. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    International Nuclear Information System (INIS)

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH2 of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  19. PCL-coated hydroxyapatite scaffold derived from cuttlefish bone: morphology, mechanical properties and bioactivity.

    Science.gov (United States)

    Milovac, Dajana; Gallego Ferrer, Gloria; Ivankovic, Marica; Ivankovic, Hrvoje

    2014-01-01

    In the present study, poly(ε-caprolactone)-coated hydroxyapatite scaffold derived from cuttlefish bone was prepared. Hydrothermal transformation of aragonitic cuttlefish bone into hydroxyapatite (HAp) was performed at 200°C retaining the cuttlebone architecture. The HAp scaffold was coated with a poly(ε-caprolactone) (PCL) using vacuum impregnation technique. The compositional and morphological properties of HAp and PCL-coated HAp scaffolds were studied by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis. Bioactivity was tested by immersion in Hank's balanced salt solution (HBSS) and mechanical tests were performed at compression. The results showed that PCL-coated HAp (HAp/PCL) scaffold resulted in a material with improved mechanical properties that keep the original interconnected porous structure indispensable for tissue growth and vascularization. The compressive strength (0.88MPa) and the elastic modulus (15.5MPa) are within the lower range of properties reported for human trabecular bones. The in vitro mineralization of calcium phosphate (CP) that produces the bone-like apatite was observed on both the pure HAp scaffold and the HAp/PCL composite scaffold. The prepared bioactive scaffold with enhanced mechanical properties is a good candidate for bone tissue engineering applications. PMID:24268280

  20. Characterization of bioactive RGD peptide immobilized onto poly(acrylic acid) thin films by plasma polymerization

    Science.gov (United States)

    Seo, Hyun Suk; Ko, Yeong Mu; Shim, Jae Won; Lim, Yun Kyong; Kook, Joong-Ki; Cho, Dong-Lyun; Kim, Byung Hoon

    2010-11-01

    Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH2 of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants.

  1. In vitro calcified matrix deposition by human osteoblasts onto a zinc-containing bioactive glass

    Directory of Open Access Journals (Sweden)

    E Saino

    2011-01-01

    Full Text Available Bioactive glasses synthesized by the sol-gel technique possess many of the qualities associated with an ideal scaffold material for a bone graft substitute. In view of the potential clinical applications, we performed a detailed in vitro study of the biological reactivity of synthesized 58S bioactive glass containing-zinc, in terms of osteoblast morphology, proliferation, and deposition of a mineralized extracellular matrix (ECM. Human Sarcoma Osteoblast (SAOS-2 cells were used to i assess cytotoxicity by lactate dehydrogenase (LDH release and ii evaluate the deposition of a calcified extracellular matrix by ELISA assay and quantitative RT-PCR (qRT-PCR. In comparison with pure silica and 58S, the 58S-Zn0.4 bioglass showed a significant increase in cellular proliferation and deposition of ECM components such as decorin, fibronectin, osteocalcin, osteonectin, osteopontin, type-I and -III collagens. Calcium deposition was significantly higher than on pure silica and 58S samples. Also Alkaline phosphatase (ALP activity and its protein content was higher with respect to pure silica and 58S. qRT-PCR analysis revealed the up-regulation of type-I collagen, bone sialoprotein and osteopontin genes. All together these results demonstrate the cytocompatibility of 58S-Zn0.4 bioglass and its capability to promote osteoblast differentiation.

  2. GC-MS analysis of bio-active compounds in methanolic extract of Lactuca runcinata DC

    Directory of Open Access Journals (Sweden)

    Lakshmi Kanta Kanthal

    2014-01-01

    Full Text Available Background: The presence of phytochemical constitutes has been reported from species of the Compositae (Asteraceae. Hitherto no reports exist on the phytochemical components and biological activity of Lactuca runcinata DC. Objective: The present study was designed to determine the bioactive compounds in the whole plant methanol extract of Lactuca runcinata. Materials and Methods: Phytochemical screening of the entire herb of Lactuca runcinata DC revealed the presence of some bio-active components. Gas chromatography-mass spectrometry (GC-MS analysis of the whole plant methanol extract of Lactuca runcinata was performed on a GC-MS equipment (Thermo Scientific Co. Thermo GC-TRACE ultra ver.: 5.0, Thermo MS DSQ II. Results: The phytochemical tests showed the presence of alkaloids, cardiac glycosides, flavonoids, phenols, phlobatannin, reducing sugars, saponins, steroids, tannins, terpenoids, volatile oils, carbohydrates, and protein/amino acids in methanolic extract of L. runcinata. The GC-MS analysis has shown the presence of different phytochemical compounds in the methanolic extract of Lactuca runcinata. A total of 21 compounds were identified representing 84.49% of total methanolic extract composition. Conclusion: From the results, it is evident that Lactuca runcinata contains various phytocomponents and is recommended as a plant of phytopharmaceutical importance.

  3. Biomimetic bonelike composites and novel bioactive glasscoatings

    Energy Technology Data Exchange (ETDEWEB)

    Tomsia, A.P.; Saiz, E.; Song, J.; Bertozzi, C.R.

    2005-06-01

    Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications.

  4. Bioactive peptide nanofibers for tissue regeneration

    OpenAIRE

    Uzunallı, Gözde

    2016-01-01

    Cataloged from PDF version of thesis. Includes bibliographical references (leaves 155-170). Thesis (Ph. D.): Bilkent University, Materials Science and Nanotechnology Program, İhsan Doğramacı Bilkent University, 2016. Defects in the tissues or organs caused by trauma or diseases can have detrimental effects on all aspects of patients’ life quality. During the last three decades, considerable developments have been made in tissue engineering and regenerative medicine in order to find a...

  5. Enhancement of bioactivity of pulsed magnetron sputtered TiCxNy with bioactive glass (BAG) incorporated polycaprolactone (PCL) composite scaffold

    International Nuclear Information System (INIS)

    Titanium carbonitride (TiCxNy) thin films were fabricated on SS 316 L by pulsed reactive DC magnetron sputtering using titanium and graphite targets. The sputtered film was characterized microstructurally by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). The XRD pattern revealed that the film was preferentially oriented along (200) axis with a grain size of 20 nm. A globular morphology was observed from electron micrograph while Energy dispersive X-ray spectroscopy (EDS) showed the compositional purity of the film. To improve the bioactivity, bioactive glass (BAG) nanopowders of size 60 nm, synthesized by sol–gel method, was incorporated into a polycaprolactone (PCL) scaffold (BAG-PCL), which was applied over TiCxNy/SS (BAG-PCL/TiCN/SS). In-vitro bioactivity studies of BAG-PCL showed the apatite formation, which was confirmed from fourier transform infrared (FTIR) spectrum and SEM. In-vitro corrosion studies in simulated body fluid (SBF) solution showed that the coated specimen had a higher charge transfer resistance than stainless steel (SS) bare. The enhancement of bioactivity was monitored by hemocompatibility and cytocompatibility, where an improved cell attachment and lower thrombus formation was observed for the coatings with BAG-PCL. - Highlights: • Fabrication of TiCxNy thin films on SS 316 L (TiCN/SS) by reactive pulsed DC magnetron sputtering. • Synthesis of BAG nanopowders (45S5) by sol–gel method. • Incorporation of BAG nanopowders into PCL matrix to form polymer composite scaffold. • BAG-PCL scaffold was coated on TiCN/SS to enhance the bioactivity

  6. In vitro evaluation of borate-based bioactive glass scaffolds prepared by a polymer foam replication method

    International Nuclear Information System (INIS)

    Borate-based bioactive glass scaffolds with a microstructure similar to that of human trabecular bone were prepared using a polymer foam replication method, and evaluated in vitro for potential bone repair applications. The scaffolds (porosity = 72 ± 3%; pore size = 250-500 μm) had a compressive strength of 6.4 ± 1.0 MPa. The bioactivity of the scaffolds was confirmed by the formation of a hydroxyapatite (HA) layer on the surface of the glass within 7 days in 0.02 M K2HPO4 solution at 37 deg. C. The biocompatibility of the scaffolds was assessed from the response of cells to extracts of the dissolution products of the scaffolds, using assays of MTT hydrolysis, cell viability, and alkaline phosphatase activity. For boron concentrations below a threshold value (0.65 mM), extracts of the glass dissolution products supported the proliferation of bone marrow stromal cells, as well as the proliferation and function of murine MLO-A5 cells, an osteogenic cell line. Scanning electron microscopy showed attachment and continuous increase in the density of MLO-A5 cells cultured on the surface of the glass scaffolds. The results indicate that borate-based bioactive glass could be a potential scaffold material for bone tissue engineering provided that the boron released from the glass could be controlled below a threshold value.

  7. The mixture of different parts of Nelumbo nucifera and two bioactive components inhibited tyrosinase activity and melanogenesis.

    Science.gov (United States)

    Jung, Su-Young; Jung, Won-Seok; Jung, Ho-Kyung; Lee, Gyeong-Hwan; Cho, Jung-Hee; Cho, Hyun-Woo; Choi, In-Young

    2014-01-01

    Melanin is the pigment responsible for the color of the eyes, hair, and skin in humans. Tyrosinase is well known to be the key enzyme in melanin biosynthesis. JKTM-12 is composed of the flowers, roots, seeds, and receptacles of Nelumbo nucifera (lotus). In this study, JKTM-12 was investigated for its inhibitory effects on tyrosinase activity and melanin biosynthesis in B16F10 melanoma cells. Moreover, two main bioactive compounds (hyperoside and astragalin) were found from the receptacles of N. nucifera, which are used as the main material of JKTM-12. JKTM-12 was shown to inhibit tyrosinase activity and melanin biosynthesis in alpha-melanocyte-stimulating hormone-stimulated B16F10 melanoma cells. Hyperoside and astragalin, which are the main bioactive compounds of JKTM-12, not only inhibited tyrosinase activity and melanogenesis but also tyrosinase-related protein 1 and tyrosinase-related protein 2 mRNA expression without cytotoxicity at various experiment doses (0.1, 1, and 10 μg/ml). These results suggest that JKTM-12 has the potential for skin whitening with hyperoside and astragalin as the main bioactive compounds. PMID:25898764

  8. In vitro evaluation of borate-based bioactive glass scaffolds prepared by a polymer foam replication method

    Energy Technology Data Exchange (ETDEWEB)

    Fu Hailuo, E-mail: fuhailuo@hotmail.com [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Institute of Bio-Engineering and IT Materials, Tongji University, Shanghai 200092 (China); Fu Qiang, E-mail: fuharry@hotmail.com [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Zhou Nai [Institute of Bio-Engineering and IT Materials, Tongji University, Shanghai 200092 (China); Huang Wenhai, E-mail: whhuang@mail.tongji.edu.cn [Institute of Bio-Engineering and IT Materials, Tongji University, Shanghai 200092 (China); Rahaman, Mohamed N. [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Wang Deping [Institute of Bio-Engineering and IT Materials, Tongji University, Shanghai 200092 (China); Liu Xin [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Institute of Bio-Engineering and IT Materials, Tongji University, Shanghai 200092 (China)

    2009-08-31

    Borate-based bioactive glass scaffolds with a microstructure similar to that of human trabecular bone were prepared using a polymer foam replication method, and evaluated in vitro for potential bone repair applications. The scaffolds (porosity = 72 {+-} 3%; pore size = 250-500 {mu}m) had a compressive strength of 6.4 {+-} 1.0 MPa. The bioactivity of the scaffolds was confirmed by the formation of a hydroxyapatite (HA) layer on the surface of the glass within 7 days in 0.02 M K{sub 2}HPO{sub 4} solution at 37 deg. C. The biocompatibility of the scaffolds was assessed from the response of cells to extracts of the dissolution products of the scaffolds, using assays of MTT hydrolysis, cell viability, and alkaline phosphatase activity. For boron concentrations below a threshold value (0.65 mM), extracts of the glass dissolution products supported the proliferation of bone marrow stromal cells, as well as the proliferation and function of murine MLO-A5 cells, an osteogenic cell line. Scanning electron microscopy showed attachment and continuous increase in the density of MLO-A5 cells cultured on the surface of the glass scaffolds. The results indicate that borate-based bioactive glass could be a potential scaffold material for bone tissue engineering provided that the boron released from the glass could be controlled below a threshold value.

  9. Review and the state of the art: Sol-gel and melt quenched bioactive glasses for tissue engineering.

    Science.gov (United States)

    Kaur, Gurbinder; Pickrell, Gary; Sriranganathan, Nammalwar; Kumar, Vishal; Homa, Daniel

    2016-08-01

    Biomaterial development is currently the most active research area in the field of biomedical engineering. The bioglasses possess immense potential for being the ideal biomaterials due to their high adaptiveness to the biological environment as well as tunable properties. Bioglasses like 45S5 has shown great clinical success over the past 10 years. The bioglasses like 45S5 were prepared using melt-quenching techniques but recently porous bioactive glasses have been derived through sol-gel process. The synthesis route exhibits marked effect on the specific surface area, as well as degradability of the material. This article is an attempt to provide state of the art of the sol-gel and melt quenched bioactive bioglasses for tissue regeneration. Fabrication routes for bioglasses suitable for bone tissue engineering are highlighted and the effect of these fabrication techniques on the porosity, pore-volume, mechanical properties, cytocompatibilty and especially apatite layer formation on the surface of bioglasses is analyzed in detail. Drug delivery capability of bioglasses is addressed shortly along with the bioactivity of mesoporous glasses. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1248-1275, 2016. PMID:26060931

  10. Effect of sintering temperature on mechanical behaviour and bioactivity of sol-gel synthesized bioglass-ceramics using rice husk ash as a silica source

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, J.P., E-mail: jyotiprakash_nitrkl@rediffmail.com [Department of Ceramic Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India); Bera, J., E-mail: bera@rediffmail.com [Department of Ceramic Engineering, National Institute of Technology, Rourkela, Odisha 769008 (India)

    2010-11-01

    Bioglass-ceramics with SiO{sub 2}-Na{sub 2}O-CaO composition was prepared by sol-gel method using rice husk ash as a silica source. Material was sintered at different temperatures ranging from 900 to 1050 deg. C for 2 h. Phase-formation behaviour, densification characteristics, and mechanical strength of glass-ceramics were investigated. The material sintered at 1000 deg. C showed a good mechanical strength. Mechanical properties were correlated with microstructural features. Both in vitro bioactivity and biodegradability of sintered material were investigated by incubating in simulated body fluid and Tris buffer solution, respectively. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to investigate the surface deposition during body fluid incubation. Both bioactivity and degradability decreased with increase in sintering temperature.

  11. The Cooking Effect on Two Edible Mushrooms in Anatolia: Fatty Acid Composition, Total Bioactive Compounds, Antioxidant and Anticholinesterase Activities

    Directory of Open Access Journals (Sweden)

    Mehmet Öztürk

    2014-03-01

    Full Text Available The effects of baking practices on the fatty acid and bioactivity of edible mushrooms; namely, Lactarius delicious and Ramaria flava, naturally growing in Anatolia were investigated. Each mushroom species was divided into two parts and one of the parts was baked. Both baked and unbaked materials were extracted with hexane and methanol, successively. The fatty acid contents of baked and unbaked extracts of both species were carried out by GC and GC-MS analytical techniques. In the unbaked extracts palmitic acid (9.7-14.43%, stearic acid (41.41-6.68%, oleic acid (25.94-47.12% and linoleic acid (22.85-9.78% were identified as major fatty acids, respectively. In the baked extracts, however, palmitic acid (7.92-19.12%, stearic acid (49.94-6.23%, oleic acid (18.07-45.13% and linoleic acid (23.36-9.25% were identified as major fatty acids, as well. The antioxidative effect of the extracts of baked and unbaked mushroom species was also determined by using four complimentary assays. In addition, the extracts and the major fatty acids were also evaluated for anticholinesterase activity against acetylcholinesterase (AChE and butyrylcholinesterase (BChE which are the chief enzymes of Alzheimer’s disease. The baked methanol extract of R. flava showed the highest activity in DPPH scavenging, ABTS scavenging and BChE assays, while the unbaked hexane extract of R. flava exhibited the best lipid peroxidation inhibition activity. In conclusion, baking proved to have influence in nutritional values and bioactivity properties of L. delicious and R. flava. The nutrient concentration and bioactivities of L. delicious were decreased when baked; however, baked R. flava proved to have higher nutrient concentrations and higher bioactivities than unbaked samples.

  12. Bioactive compounds of sea cucumbers and their therapeutic effects

    Science.gov (United States)

    Shi, Shujuan; Feng, Wenjing; Hu, Song; Liang, Shixiu; An, Nina; Mao, Yongjun

    2015-11-01

    Sea cucumbers belong to the Class Holothuroidea of marine invertebrates. They are commercially valuable and prized as a food and folk medicine in Asia. Nutritionally, sea cucumbers have an impressive profile of valuable nutrients such as vitamins, minerals and amino acids. A number of unique biological and pharmacological activities/properties, including anticancer, anticoagulant/antithrombotic, antimicrobial, antioxidant, antihyperlipidemic, antihyperglycemic, anti-inflammatory, antihypertension and radioprotective, have been ascribed to various compounds isolated from sea cucumbers. The therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array of bioactives, especially triterpene glycosides, acid mucopolysaccharide, sphingoid bases, glycolipids, fucosylated chondroitin sulfate, polysaccharides, phospholipids, cerebrosides, phosphatidylcholines, and other extracts and hydrolysates. This review highlights the valuable bioactive components as well as the multiple therapeutic properties of sea cucumbers with a view to exploring their potential uses as functional foods and a natural source of new multifunctional drugs.

  13. Preparation of bioactive porous HA/PCL composite scaffolds

    Science.gov (United States)

    Zhao, J.; Guo, L. Y.; Yang, X. B.; Weng, J.

    2008-12-01

    Porous hydroxyapatite (HA) bioceramic scaffold has been widely attracted the attention to act as a three-dimensional (3D) template for cell adhesion, proliferation, differentiation and thus promoting bone and cartilage regeneration because of its osteoinduction. However, the porous bioceramic scaffold is fragile so that it is not suitable to be applied in clinic for bone repair or replacement. Therefore, it is significant to improve the mechanical property of porous HA bioceramics while the interconnected structure is maintained for tissue ingrowth in vivo. In the present research, a porous composite scaffold composed of HA scaffold and polycaprolactone (PCL) lining was fabricated by the method of polymer impregnating to produce HA scaffold coated with PCL lining. Subsequently, the composite scaffolds were deposited with biomimetic coating for improving the bioactivity. The HA/PCL composite scaffolds with improved mechanical property and bioactivity is expected to be a promising bone substitute in tissue engineering applications.

  14. Preparation of bioactive porous HA/PCL composite scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, J.; Guo, L.Y.; Yang, X.B. [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Weng, J. [Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)], E-mail: jweng@swjtu.cn

    2008-12-30

    Porous hydroxyapatite (HA) bioceramic scaffold has been widely attracted the attention to act as a three-dimensional (3D) template for cell adhesion, proliferation, differentiation and thus promoting bone and cartilage regeneration because of its osteoinduction. However, the porous bioceramic scaffold is fragile so that it is not suitable to be applied in clinic for bone repair or replacement. Therefore, it is significant to improve the mechanical property of porous HA bioceramics while the interconnected structure is maintained for tissue ingrowth in vivo. In the present research, a porous composite scaffold composed of HA scaffold and polycaprolactone (PCL) lining was fabricated by the method of polymer impregnating to produce HA scaffold coated with PCL lining. Subsequently, the composite scaffolds were deposited with biomimetic coating for improving the bioactivity. The HA/PCL composite scaffolds with improved mechanical property and bioactivity is expected to be a promising bone substitute in tissue engineering applications.

  15. Preparation of bioactive porous HA/PCL composite scaffolds

    International Nuclear Information System (INIS)

    Porous hydroxyapatite (HA) bioceramic scaffold has been widely attracted the attention to act as a three-dimensional (3D) template for cell adhesion, proliferation, differentiation and thus promoting bone and cartilage regeneration because of its osteoinduction. However, the porous bioceramic scaffold is fragile so that it is not suitable to be applied in clinic for bone repair or replacement. Therefore, it is significant to improve the mechanical property of porous HA bioceramics while the interconnected structure is maintained for tissue ingrowth in vivo. In the present research, a porous composite scaffold composed of HA scaffold and polycaprolactone (PCL) lining was fabricated by the method of polymer impregnating to produce HA scaffold coated with PCL lining. Subsequently, the composite scaffolds were deposited with biomimetic coating for improving the bioactivity. The HA/PCL composite scaffolds with improved mechanical property and bioactivity is expected to be a promising bone substitute in tissue engineering applications

  16. Chemical constituents and bioactivity of Formosan lauraceous plants

    Directory of Open Access Journals (Sweden)

    Hsun-Shuo Chang

    2016-04-01

    Full Text Available Taiwan is rich in lauraceous plants. A review of 197 references based on the chemical analysis and bioactivity of indigenous lauraceous plants carried out by native scientists from 1963 to 2014 has been compiled. About 303 new compounds and thousands of known compounds comprising alkaloids and non-alkaloids with diverse structures have been isolated or identified from indigenous plants belonging to the 11 lauraceous genera. The volatile components, however, have been excluded from this review. This review provides an overview of the past efforts of Taiwan scientists working on secondary metabolites and their bioactivity in native lauraceous plants. The potential of lauraceous plants worthy of further study is also noted. The contents will be helpful for the chemotaxonomy of Lauraceae and be of value for the development of native Formosan lauraceous plants.

  17. Variation of bioactive compounds content of 14 oriental strawberry cultivars.

    Science.gov (United States)

    Kim, Sung Kyeom; Kim, Dong Sub; Kim, Dae Young; Chun, Changhoo

    2015-10-01

    Variation in bioactive compounds content was assessed in antioxidant rich June-bearing strawberry cultivars. Ascorbic acid, anthocyanin, and ellagic acid content were analyzed in ripe fruits of 14 cultivars. The bioactive content in strawberry fruit was found to vary significantly among cultivars and from year to year. The highest ascorbic acid content was found in 'Sugyeong'. The 'Red Pearl' and 'Sachinoka' had three to fourfold higher amounts of pelargonidin 3-glucoside than other cultivars. For cyanidin 3-glucoide and pelargonidin 3-rutinoside, two other characterized anthocyanins, 'Dahong' and 'Keumhyang' had the highest contents among all the tested cultivars. The ellagic acid content of 'Dahong' was generally all within the upper ranges. These results can be used for the validation of fruit antioxidant capacity and in addition, provide useful information for breeding programs looking to enhance the antioxidant capacity in strawberry fruit. PMID:25872444

  18. Bioactive compounds of sea cucumbers and their therapeutic effects

    Science.gov (United States)

    Shi, Shujuan; Feng, Wenjing; Hu, Song; Liang, Shixiu; An, Nina; Mao, Yongjun

    2016-05-01

    Sea cucumbers belong to the Class Holothuroidea of marine invertebrates. They are commercially valuable and prized as a food and folk medicine in Asia. Nutritionally, sea cucumbers have an impressive profile of valuable nutrients such as vitamins, minerals and amino acids. A number of unique biological and pharmacological activities/properties, including anticancer, anticoagulant/antithrombotic, antimicrobial, antioxidant, antihyperlipidemic, antihyperglycemic, anti-inflammatory, antihypertension and radioprotective, have been ascribed to various compounds isolated from sea cucumbers. The therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array of bioactives, especially triterpene glycosides, acid mucopolysaccharide, sphingoid bases, glycolipids, fucosylated chondroitin sulfate, polysaccharides, phospholipids, cerebrosides, phosphatidylcholines, and other extracts and hydrolysates. This review highlights the valuable bioactive components as well as the multiple therapeutic properties of sea cucumbers with a view to exploring their potential uses as functional foods and a natural source of new multifunctional drugs.

  19. Enhanced Antifungal Bioactivity of Coptis Rhizome Prepared by Ultrafining Technology

    Directory of Open Access Journals (Sweden)

    Ping-Chung Kuo

    2014-01-01

    Full Text Available The aim of this study was to identify and quantify the bioactive constituents in the methanol extracts of Coptis Rhizome prepared by ultrafining technology. The indicator compound was identified by spectroscopic method and its purity was determined by HPLC. Moreover, the crude extracts and indicator compound were examined for their ability to inhibit the growth of Rhizoctonia solani Kühn AG-4 on potato dextrose agar plates. The indicator compound is a potential candidate as a new plant derived pesticide to control Rhizoctonia damping-off in vegetable seedlings. In addition, the extracts of Coptis Rhizome prepared by ultrafining technology displayed higher contents of indicator compound; they not only improve their bioactivity but also reduce the amount of the pharmaceuticals required and, thereby, decrease the environmental degradation associated with the harvesting of the raw products.

  20. Review: Mycoendophytes in medicinal plants: Diversity and bioactivities

    Directory of Open Access Journals (Sweden)

    MUDASIR DAR

    2012-07-01

    Full Text Available Rai M, Gade A, Rathod D, Dar M, Varma A. 2012. Review: Mycoendophytes in medicinal plants: Diversity and bioactivities. Nusantara Bioscience 4: 86-96. Endophytes are microorganisms that reside in internal tissues of living plants without causing any negative effect. These offer tremendous potential for the exploitation of novel and eco-friendly secondary metabolites used in medicine, the pharmaceutical industry and agriculture. The present review is focused on diversity of endophytes, current national and international bioactive secondary metabolite scenario and future prospects. Endophytic fungi as novel source of potentially useful medicinal compounds are discussed along with the need to search for new and more effective agents from endophytes to combat disease problems.

  1. Bioactivity of zirconia nanotube arrays fabricated by electrochemical anodization

    International Nuclear Information System (INIS)

    Zirconia nanotubes with a diameter of 50 nm and a length of 20 μm were fabricated by anodic oxidation of zirconium in (NH4)2SO4 electrolyte containing NH4F. The structure and phase composition of the zirconia nanotube layers were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The bioactivity was assessed by investigating the formation of apatite on the surface of zirconia nanotubes after soaking in simulated body fluids (SBF) for 20-30 days. The results indicate that bone-like apatite can be formed on the surface of the zirconia nanotube layers in our SBF immersion experiments. Microstructure of zirconia nanotubes with apatite layer was observed by SEM. Substance and phase compositions were characterized respectively by energy dispersive X-ray spectrometer (EDS) and XRD. Our results show that zirconia nanotube layers fabricated by electrochemical anodization exhibit favorable bioactivity.

  2. Laser thermal effect on silicon nitride ceramic based on thermo-chemical reaction with temperature-dependent thermo-physical parameters

    Science.gov (United States)

    Pan, A. F.; Wang, W. J.; Mei, X. S.; Wang, K. D.; Zhao, W. Q.; Li, T. Q.

    2016-07-01

    In this study, a two-dimensional thermo-chemical reaction model with temperature-dependent thermo-physical parameters on Si3N4 with 10 ns laser was developed to investigate the ablated size, volume and surface morphology after single pulse. For model parameters, thermal conductivity and heat capacity of β-Si3N4 were obtained from first-principles calculations. Thermal-chemical reaction rate was fitted by collision theory, and then, reaction element length was deduced using the relationship between reaction rate and temperature distribution. Furthermore, plasma absorption related to energy loss was approximated as a function of electron concentration in Si3N4. It turned out that theoretical ablated volume and radius increased and then remained constant with increasing laser energy, and the maximum ablated depth was not in the center of the ablated zone. Moreover, the surface maximum temperature of Si3N4 was verified to be above 3000 K within pulse duration, and it was much higher than its thermal decomposition temperature of 1800 K, which indicated that Si3N4 was not ablated directly above the thermal decomposition temperature. Meanwhile, the single pulse ablation of Si3N4 was performed at different powers using a TEM00 10 ns pulse Nd:YAG laser to validate the model. The model showed a satisfactory consistence between the experimental data and numerical predictions, presenting a new modeling technology that may significantly increase the accuracy of the predicated results for laser ablation of materials undergoing thermo-chemical reactions.

  3. Bioactivity studies of calcium magnesium silicate prepared from eggshell waste by sol–gel combustion synthesis

    Directory of Open Access Journals (Sweden)

    Rajan Choudhary

    2015-06-01

    Full Text Available The present study focused on the synthesis of calcium magnesium silicate (akermanite, Ca2MgSi2O7 using eggshell biowaste (as calcium source, magnesium nitrate and tetraethyl orthosilicate (TEOS as starting materials. Sol–gel combustion method was adopted to obtain calcium magnesium silicate. Citric acid was used as a fuel (reducing agent and nitrate ions present in the metal nitrates acts as an oxidizing agent during combustion process. The characterization of synthesized calcium magnesium silicate was carried out by powder X-ray diffraction (XRD, Fourier transform infrared (FTIR and scanning electron microscopy (SEM techniques. Calcium magnesium silicate crystallite size was observed in nano regime which can effectively mimic natural bone apatite composition. In-vitro bioactivity was investigated by immersing calcium magnesium silicate pellet in simulated body fluid (SBF for three weeks. Results show effective deposition of crystallized hydroxyapatite (HAP layer on its surface and predicting its possibilities for applications in hard tissue regeneration.

  4. Bioactive Coatings for Orthopaedic Implants—Recent Trends in Development of Implant Coatings

    Directory of Open Access Journals (Sweden)

    Bill G. X. Zhang

    2014-07-01

    Full Text Available Joint replacement is a major orthopaedic procedure used to treat joint osteoarthritis. Aseptic loosening and infection are the two most significant causes of prosthetic implant failure. The ideal implant should be able to promote osteointegration, deter bacterial adhesion and minimize prosthetic infection. Recent developments in material science and cell biology have seen the development of new orthopaedic implant coatings to address these issues. Coatings consisting of bioceramics, extracellular matrix proteins, biological peptides or growth factors impart bioactivity and biocompatibility to the metallic surface of conventional orthopaedic prosthesis that promote bone ingrowth and differentiation of stem cells into osteoblasts leading to enhanced osteointegration of the implant. Furthermore, coatings such as silver, nitric oxide, antibiotics, antiseptics and antimicrobial peptides with anti-microbial properties have also been developed, which show promise in reducing bacterial adhesion and prosthetic infections. This review summarizes some of the recent developments in coatings for orthopaedic implants.

  5. Atomic and vibrational origins of mechanical toughness in bioactive cement during setting

    Science.gov (United States)

    Tian, Kun V.; Yang, Bin; Yue, Yuanzheng; Bowron, Daniel T.; Mayers, Jerry; Donnan, Robert S.; Dobó-Nagy, Csaba; Nicholson, John W.; Fang, De-Cai; Greer, A. Lindsay; Chass, Gregory A.; Greaves, G. Neville

    2015-11-01

    Bioactive glass ionomer cements (GICs) have been in widespread use for ~40 years in dentistry and medicine. However, these composites fall short of the toughness needed for permanent implants. Significant impediment to improvement has been the requisite use of conventional destructive mechanical testing, which is necessarily retrospective. Here we show quantitatively, through the novel use of calorimetry, terahertz (THz) spectroscopy and neutron scattering, how GIC's developing fracture toughness during setting is related to interfacial THz dynamics, changing atomic cohesion and fluctuating interfacial configurations. Contrary to convention, we find setting is non-monotonic, characterized by abrupt features not previously detected, including a glass-polymer coupling point, an early setting point, where decreasing toughness unexpectedly recovers, followed by stress-induced weakening of interfaces. Subsequently, toughness declines asymptotically to long-term fracture test values. We expect the insight afforded by these in situ non-destructive techniques will assist in raising understanding of the setting mechanisms and associated dynamics of cementitious materials.

  6. Bioactive molecules: current trends in discovery, synthesis, delivery and testing

    OpenAIRE

    Yew Beng Kang; Pichika R Mallikarjuna; Davamani A Fabian; Adinarayana Gorajana; Chooi Ling Lim; Eng Lai Tan

    2013-01-01

    Important bioactive molecules are moleculesthat are pharmacologically active derived from naturalsources and through chemical synthesis. Over the yearsmany of such molecules have been discovered throughbioprospective endeavours. The discovery of taxol fromthe pacific yew tree bark that has the ability in stabilisingcellular microtubules represents one of the hallmarks ofsuccess of such endeavours. In recent years, the discoveryprocess has been aided by the rapid developmentof techniques and t...

  7. Bis(indolyl)methane alkaloids: Isolation, bioactivity, and syntheses

    Digital Repository Service at National Institute of Oceanography (India)

    Praveen, P.; Parameswaran, P.S.; Majik, M.S.

    Author version: Synthesis - Stuttgart, vol.47; 2015; 1827-1837 Bisindolyl Methane Alkaloids: Isolation, Bioactivity and Syntheses P. J. Praveen,a,b P. S. Parameswaran*b, M. S. Majik*c aCSIR-National Institute of Oceanography, Bioorganic Chemistry... Laboratory, Dona Paula Goa- India; bCSIR-National Institute of Oceanography Regional centre, Kochi, India, Email:param@nio.org; cDepartment of Chemistry, Goa University, Goa 403 206, India, Email:majikms@gmail.com Abstract Bis...

  8. Bioactivities from Marine Algae of the Genus Gracilaria

    OpenAIRE

    José M. Barbosa-Filho; Maria de Fátima V. de Souza; Luis C. Rodrigues; Athayde-Filho, Petrônio F.; Lira, Narlize S.; Camila De A. Montenegro; Lima, Gedson R. de M.; Batista, Leônia M.; Falcão, Heloina de S.; de Almeida, Cynthia Layse F.

    2011-01-01

    Seaweeds are an important source of bioactive metabolites for the pharmaceutical industry in drug development. Many of these compounds are used to treat diseases like cancer, acquired immune-deficiency syndrome (AIDS), inflammation, pain, arthritis, as well as viral, bacterial, and fungal infections. This paper offers a survey of the literature for Gracilaria algae extracts with biological activity, and identifies avenues for future research. Nineteen species of this genus that were tested fo...

  9. Hyaluronic Acid Bioconjugates for the Delivery of Bioactive Molecules

    OpenAIRE

    Anna Mero; Monica Campisi

    2014-01-01

    Hyaluronic acid (HA) has currently several therapeutic applications: in ophthalmology, osteoarthritis, wound healing, tissue regeneration, postoperative anti-adhesion and anesthetic medicine. In the last ten years, it has also been successfully investigated in the field of drug delivery, in the form of conjugates or hydrogel depot systems. HAylation, the covalent conjugation of HA to bioactive molecules, allows the overcoming of disadvantages associated with some pharmaceuticals, such as inso...

  10. Isolation and identification of bioactive compounds in Andrographis paniculata (Chuanxinlian)

    OpenAIRE

    Lin Bi-Fong; Chao Wen-Wan

    2010-01-01

    Abstract Andrographis paniculata (Burm. f.) Nees (Acanthaceae) is a medicinal plant used in many countries. Its major constituents are diterpenoids, flavonoids and polyphenols. Among the single compounds extracted from A. paniculata, andrographolide is the major one in terms of bioactive properties and abundance. Among the andrographolide analogues, 14-deoxy-11,12-didehydroandrographolide is immunostimulatory, anti-infective and anti-atherosclerotic; neoandrographolide is anti-inflammatory, a...

  11. Preventive and Prophylactic Mechanisms of Action of Pomegranate Bioactive Constituents

    OpenAIRE

    Monica Viladomiu; Raquel Hontecillas; Pinyi Lu; Josep Bassaganya-Riera

    2013-01-01

    Pomegranate fruit presents strong anti-inflammatory, antioxidant, antiobesity, and antitumoral properties, thus leading to an increased popularity as a functional food and nutraceutical source since ancient times. It can be divided into three parts: seeds, peel, and juice, all of which seem to have medicinal benefits. Several studies investigate its bioactive components as a means to associate them with a specific beneficial effect and develop future products and therapeutic applications. Man...

  12. The Constituents of Michelia compressa var. formosana and Their Bioactivities

    OpenAIRE

    Yu-Yi Chan; Shin-Hun Juang; Guan-Jhong Huang; Yu-Ren Liao; Yu-Fon Chen; Chia-Che Wu; Hui-Ting Chang; Tian-Shung Wu

    2014-01-01

    Phytochemical investigation of the heartwood of Michelia compressa afforded forty-four compounds, which were identified by comparison of experimental and literature analytical and spectroscopic data. Some compounds were evaluated for their anti-inflammatory and anticancer bioactivities. The result showed that soemerine (1) and cyathisterol (2) exhibited significant nitric oxide (NO) inhibition, with IC50 values of 8.5 ± 0.3 and 9.6 ± 0.5 µg/mL, respectively. In addition, liriodenine (3) and ...

  13. Losses of bioactive polyacetylenes during minimal processing of carrots

    OpenAIRE

    Koidis, Anastasios; Rawson, Ashish; Osorio, Teresa; Brunton, Nigel

    2011-01-01

    Vegetables of the Apiaceae plant family such as carrots, parsnip, celery and parsley,contain in minor quantities, a group of bioactive aliphatic C17-polyacetylenes (falcarinol,falcarindiol, falcarindiol-3- acetate). Recent studies have highlighted important biologicalfunctions in vitro and in vivo (animal studies) although the beneficial effect in humannutrition attributable to an increased in polyacetylenes diet are yet to be confirmed(Lund, 1990).Carrots not only contain relatively high pol...

  14. Total synthesis and development of bioactive natural products

    OpenAIRE

    TATSUTA, Kuniaki

    2008-01-01

    The first total synthesis and development of a variety of bioactive natural products have been accomplished by using carbohydrates as a chiral source. In addition, practically useful intermediates have been created, analogs of natural products have been prepared, their structure-activity relationships studied, and the large-scale preparations of medicinally useful compounds established. The key target molecules have been the “Big Four” antibiotics (macrolides, aminoglycosides, β-lactams and t...

  15. Bioinformatics approaches for identifying new therapeutic bioactive peptides in food

    OpenAIRE

    Nora Khaldi

    2012-01-01

    ABSTRACT:The traditional methods for mining foods for bioactive peptides are tedious and long. Similar to the drug industry, the length of time to identify and deliver a commercial health ingredient that reduces disease symptoms can take anything between 5 to 10 years. Reducing this time and effort is crucial in order to create new commercially viable products with clear and important health benefits. In the past few years, bioinformatics, the science that brings together fast computational b...

  16. Chemical Constituents and Bioactivities of Clinacanthus nutans Aerial Parts

    Directory of Open Access Journals (Sweden)

    Shu-Fen Tu

    2014-12-01

    Full Text Available Four new sulfur-containing compounds, named clinamides A-C (1–3, and 2-cis-entadamide A (4, were isolated together with three known compounds from the bioactive ethanol extract of the aerial parts of Clinacanthus nutans. These secondary metabolites possess sulfur atoms and acrylamide functionalities. The structures of the isolated components were established by interpretation of their spectroscopic data, especially 1D and 2D NMR.

  17. Chemical Constituents and Bioactivities of Clinacanthus nutans Aerial Parts

    OpenAIRE

    Shu-Fen Tu; Rosa Huang Liu; Yuan-Bin Cheng; Yu-Ming Hsu; Ying-Chi Du; Mohamed El-Shazly; Yang-Chang Wu; Fang-Rong Chang

    2014-01-01

    Four new sulfur-containing compounds, named clinamides A-C (1–3), and 2-cis-entadamide A (4), were isolated together with three known compounds from the bioactive ethanol extract of the aerial parts of Clinacanthus nutans. These secondary metabolites possess sulfur atoms and acrylamide functionalities. The structures of the isolated components were established by interpretation of their spectroscopic data, especially 1D and 2D NMR.

  18. Chemical constituents and bioactivities of Clinacanthus nutans aerial parts.

    Science.gov (United States)

    Tu, Shu-Fen; Liu, Rosa Huang; Cheng, Yuan-Bin; Hsu, Yu-Ming; Du, Ying-Chi; El-Shazly, Mohamed; Wu, Yang-Chang; Chang, Fang-Rong

    2014-01-01

    Four new sulfur-containing compounds, named clinamides A-C (1-3), and 2-cis-entadamide A (4), were isolated together with three known compounds from the bioactive ethanol extract of the aerial parts of Clinacanthus nutans. These secondary metabolites possess sulfur atoms and acrylamide functionalities. The structures of the isolated components were established by interpretation of their spectroscopic data, especially 1D and 2D NMR. PMID:25490430

  19. Chemical composition of bioactive pressurized extracts of Romanian aromatic plants

    OpenAIRE

    Miron, T. L.; Plaza, Merichel; Bahrim, G.; Ibáñez, Elena; Herrero, Miguel

    2011-01-01

    In this contribution, pressurized liquid extraction (PLE) has been employed to isolate bioactive compounds from three native Romanian plants, oregano (Origanum vulgare), tarragon (Artemisia dracunculus) and wild thyme (Thymus serpyllum). Different PLE conditions have been tested including extraction with water, ethanol and their mixtures in a wide range of extraction temperatures (50–200 °C), and the antioxidant capacity of the extracts was measured using different assays (DPPH radical scaven...

  20. Study on bioactivity of NiTinol after surface treatment

    OpenAIRE

    W. Chrzanowski; W. Walke; Armitage, D. A.; Knowles, J. C.

    2008-01-01

    Purpose: The aim of the work was to assess bioactive properties and corrosion resistance of nickel titanium alloyafter alkali treatment and spark oxidation in Hank’s Balance Salt Solution.Design/methodology/approach: Surfaces of samples were prepared by chemical treatment in NaOHfollowed by heat treatment, and spark oxidation. Corrosion resistance was investigated using potentiodynamicmethod. Chemical composition of the samples surface was measured using SEM EDX. Surface roughness andtopograp...

  1. Constructing bioactive peptides with pH-dependent activities

    OpenAIRE

    Tu, Zhigang; Volk, Melanie; Shah, Khushali; Clerkin, Kevin; Liang, Jun F.

    2009-01-01

    Many bioactive peptides are featured by their arginine and lysine rich contents. In this study, lysine and arginine residues in lytic peptides were selectively replaced by histidines. Although resulted histidine-containing lytic peptides had decreased activity, they did show pH-dependent cytotoxicity. The activity of the constructed histidine-containing lytic peptides increased 2 ~ 8 times as the solution pH changed from of 7.4 to 5.5. More importantly, these histidine-containing peptides mai...

  2. Environmental sustainability of bioactive molecules from marine organisms

    OpenAIRE

    Pérez López, Paula

    2015-01-01

    Marine and freshwater ecosystems have been widely exploited throughout history as vast sources of food and valuable natural products. The diversity of aquatic organisms has led to the isolation of more than 24000 bioactive compounds with applications in strategic industries such as pharmaceutical, nutraceutical and cosmetic sectors. Moreover, the biochemical composition and growth characteristics of microalgae and seaweeds suggest their capability to overcome some bottleneck...

  3. Evaluating Bioactive Food Components in Obesity and Cancer Prevention

    OpenAIRE

    Crowe, Kristi M.; Allison, David

    2015-01-01

    Research into bioactive food compounds (BFC) continues to evolve albeit with shared challenges among scientists in the fields of obesity and cancer treatment and prevention. Given the diversity of scientific disciplines involved in evaluating BFC, multi-disciplinary conferences provide opportunities to update the state of the science and critically discuss conceptual and methodological challenges encountered in studying BFC in both pre-clinical and clinical trials. This overview is an introdu...

  4. Compressed fluids for the extraction of bioactive compounds

    OpenAIRE

    Herrero, Miguel; Castro-Puyana, M.; Mendiola, J. A.; Ibáñez, Elena

    2013-01-01

    The improvement of sample-preparation and extraction techniques for determinations of natural bioactive compounds is very important. New concepts relate to not only enhancement of extraction efficiencies but also environmental impact. This evolution towards Green Analytical Chemistry is to new extraction and sample-preparation processes that should be faster, more reproducible and more environmentally friendly.Compressed fluid-based sample-preparation techniques (e.g., supercritical fluid ext...

  5. Bioactive compounds in baby spinach (Spinacia oleracea L.)

    OpenAIRE

    Bergquist, Sara

    2006-01-01

    A high intake of fruit and vegetables is well known to have positive effects on human health, and has been correlated to a decreased risk of most degenerative diseases of ageing, such as cardiovascular disease, cataracts and several forms of cancer. These protective effects have been attributed to high concentrations of bioactive compounds (ascorbic acid, flavonoids, carotenoids) in fruit and vegetables, partly due to the antioxidative action of some of these compounds. Maintaining a high lev...

  6. Bioactive substances of plant origin in food - impact on genomics

    OpenAIRE

    Orzechowski, Arkadiusz; Ostaszewski, Piotr; Jank, Michał; Berwid, Sybilla

    2002-01-01

    International audience In the past decade, substantial progress has been made concerning our knowledge of bioactive components in plant foods and their links to health. Human diets of plant origin contain many hundreds of compounds which cannot be considered as nutrients, but appear to play a role in the maintenance of health. These substances are called nutraceuticals. In some cases where the disease process is at least partially understood, elements of protection can be related to a sing...

  7. The Artemisia L. Genus: A Review of Bioactive Essential Oils

    OpenAIRE

    Paulina Bermejo; Luis Apaza; Luis Miguel Bedoya; María José Abad

    2012-01-01

    Numerous members of the Anthemideae tribe are important as cut flowers and ornamental crops, as well as being medicinal and aromatic plants, many of which produce essential oils used in folk and modern medicine and in the cosmetics and pharmaceutical industry. Essential oils generally have a broad spectrum of bioactivity, owing to the presence of several active ingredients that work through various modes of action. Due to their mode of extraction, mostly by distillation from aromatic plants, ...

  8. Titanium Foam-Bioactive Nanofiber Hybrids for Bone Regeneration

    OpenAIRE

    Sargeant, Timothy D; Oppenheimer, Scott M.; Dunand, David C.; Stupp, Samuel I.

    2008-01-01

    We have reported previously a method to introduce bioactive nanofiber networks through self-assembly into the pores of titanium alloy foams for bone repair. In this study we evaluate the in vitro colonization by mouse pre-osteoblastic cells of these metal-peptide amphiphile hybrids containing phosphoserine residues and the RGDS epitope. The aim was to determine the effect of varying the RGDS epitope concentration within a given range, and confirm the ability for cells to infiltrate and surviv...

  9. Neutral atom beam technique enhances bioactivity of PEEK

    Energy Technology Data Exchange (ETDEWEB)

    Khoury, Joseph, E-mail: jkhoury@exogenesis.us [Exogenesis Corporation, Billerica, MA 01821 (United States); Kirkpatrick, Sean R.; Maxwell, Melissa; Cherian, Raymond E.; Kirkpatrick, Allen; Svrluga, Richard C. [Exogenesis Corporation, Billerica, MA 01821 (United States)

    2013-07-15

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants.

  10. Neutral atom beam technique enhances bioactivity of PEEK

    International Nuclear Information System (INIS)

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants

  11. Neutral atom beam technique enhances bioactivity of PEEK

    Science.gov (United States)

    Khoury, Joseph; Kirkpatrick, Sean R.; Maxwell, Melissa; Cherian, Raymond E.; Kirkpatrick, Allen; Svrluga, Richard C.

    2013-07-01

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants.

  12. Enhanced Antifungal Bioactivity of Coptis Rhizome Prepared by Ultrafining Technology

    OpenAIRE

    Ping-Chung Kuo; Yao-Tung Lin; Mei-Lin Yang; Ming-Yuan Liao; Guo-Feng Chen; Po-Hsun Chen; Lin-Fu Wong; Jenn-Wen Huang

    2014-01-01

    The aim of this study was to identify and quantify the bioactive constituents in the methanol extracts of Coptis Rhizome prepared by ultrafining technology. The indicator compound was identified by spectroscopic method and its purity was determined by HPLC. Moreover, the crude extracts and indicator compound were examined for their ability to inhibit the growth of Rhizoctonia solani Kühn AG-4 on potato dextrose agar plates. The indicator compound is a potential candidate as a new plant derive...

  13. Bioactivity of microencapsulated soursop seeds extract on Plutella xylostella

    OpenAIRE

    Ismael Barros Gomes; Roseane Cristina Predes Trindade; Antônio Euzébio Goulart Sant'Ana; Eurico Eduardo Pinto Lemos; Irinaldo Diniz Basílio Júnior

    2016-01-01

    ABSTRACT: The aim of this study was to evaluate the bioactivity of microencapsulated extract from the soursop seeds, Annona muricata L. ( Annonaceae ), on diamondback moth, Plutella xylostela L. (Lepidoptera: Plutellidae ). Microencapsulation was performed in a Mini Spray Dryer model B-290 using 50mL of ethanolic and hexanic extracts plus 150mL of ethanol and 150mL of ultrapure water, mixed with aerosil (first polymer) or arabic gum (second polymer). It was possible to microencapsulate the...

  14. Physicochemical, microbiological and sensory evaluation of a bioactive food blend

    OpenAIRE

    Rosângela dos Santos Ferreira; Priscila Aiko Hiane; Rita de Cássia Avellaneda Guimarães; Maria Isabel Lima Ramos; Daniel Pecoraro Demarque; Júnia Elisa Carvalho de Meira

    2014-01-01

    The potential of functional foods to decrease the risks of chronic non-communicable diseases has motivated the development of products with beneficial effects on fat and carbohydrate metabolism. The present study aimed at analyzing the physicochemical, microbiological, and sensory properties of a bioactive food blend developed to help the nutritional therapy provided to hypolipidemic and hyperglycemic patients with HIV/AIDS treated with antiretroviral therapy. The food blend was evaluated for...

  15. Fast rule-based bioactivity prediction using associative classification mining

    OpenAIRE

    Yu Pulan; Wild David J

    2012-01-01

    Abstract Relating chemical features to bioactivities is critical in molecular design and is used extensively in the lead discovery and optimization process. A variety of techniques from statistics, data mining and machine learning have been applied to this process. In this study, we utilize a collection of methods, called associative classification mining (ACM), which are popular in the data mining community, but so far have not been applied widely in cheminformatics. More specifically, class...

  16. The interaction of bioactive peptides with an immobilized phosphatidylcholine monolayer.

    OpenAIRE

    Mozsolits, H; Lee, T. H.; Wirth, H J; Perlmutter, P; Aguilar, M I

    1999-01-01

    The interaction of three bioactive peptides, bombesin, beta-endorphin, and glucagon with a phosphatidylcholine monolayer that was immobilized to porous silica particles and packed into a stainless steel column cartridge, has been studied using dynamic elution techniques. This immobilized lipid monolayer provides a biophysical model system with which to study the binding of peptides to a lipid membrane. In particular, the influence of temperature and methanol concentration on the affinity of e...

  17. Expanding opportunities for mining bioactive chemistry from patents.

    Science.gov (United States)

    Southan, Christopher

    2015-07-01

    Bioactive structures published in medicinal chemistry patents typically exceed those in papers by at least twofold and may precede them by several years. The Big-Bang of open automated extraction since 2012 has contributed to over 15 million patent-derived compounds in PubChem. While mapping between chemical structures, assay results and protein targets from patent documents is challenging, these relationships can be harvested using open tools and are beginning to be curated into databases. PMID:26194581

  18. Fabrication, structure and biological properties of organic acid-derived sol-gel bioactive glasses

    International Nuclear Information System (INIS)

    Sol-gel-derived bioactive glasses (BGs) have been developed for bone tissue regeneration. To develop more reliable bone tissue repair systems, it is necessary to control the morphology and surface textures of bioactive glasses. In this study, we prepared bioactive glasses by sol-gel technology using hydrochloride acid, lactic acid, citric acid and acetic acid as hydrolysis catalysts. We studied effects of acids on the morphology and surface textures, apatite-forming bioactivity and cellular response (cellular attachment and proliferation) of BGs. Results showed that the surface morphology, structure, apatite-forming bioactivity and cellular response of BG particles can be controlled by changing acid species. The hydrochloric acid-derived bioactive glass (HBG) and the acetic acid-derived bioactive glass (ABG) present high surface areas and fast apatite-forming rates. Lactic acid- and citric acid-derived bioactive glasses (LBG, CBG) exhibited nanoscale surface morphology, relatively low surface areas and comparable apatite-forming bioactivity. The results of human marrow mesenchymal stem cell (HMSC) culture exhibited that LBG and CBG have an enhanced effect on the cell proliferation, as compared to HBG, ABG and tissue culture plate. This study suggests that sol-gel bioactive glasses with proper surface textures and apatite-forming rate can affect preliminary cellular proliferation.

  19. The Correlation of Surfactant Concentrations on the Properties of Mesoporous Bioactive Glass

    Directory of Open Access Journals (Sweden)

    Shao-Ju Shih

    2016-01-01

    Full Text Available Bioactive glass (BG, a potential biomaterial, has received increasing attention since the discovery of its superior bioactivity. One of the main research objectives is to improve the bioactive property of BGs; therefore, surfactant-derived mesoporous bioactive glasses (MBGs were developed to provide a high specific surface area for achieving higher bioactivity. In this study, various concentrations of typical triblock F127 surfactant were used to manipulate the morphology, specific surface area, and bioactivity of MBG particles. Two typical morphologies of smooth (Type I and wrinkled (Type II spheres were observed, and the population of Type II particles increased with an increase in the surfactant concentration. A direct correlation between specific surface area and bioactivity was observed by comparing the data obtained using the nitrogen adsorption-desorption method and in vitro bioactive tests. Furthermore, the optimal surfactant concentration corresponding to the highest bioactivity revealed that the surfactant aggregated to form Type II particles when the surface concentration was higher than the critical micelle concentration, and the high population of Type II particles may reduce the specific surface area because of the loss of bioactivity. Moreover, the formation mechanism of SP-derived MBG particles is discussed.

  20. Evaluation of bioactive glass and demineralized freeze dried bone allograft in the treatment of periodontal intraosseous defects: A comparative clinico-radiographic study

    Directory of Open Access Journals (Sweden)

    Kishore Kumar Katuri

    2013-01-01

    Full Text Available Aim: The purpose of this study was to evaluate the efficacy of demineralized freeze dried bone allograft (DFDBA and bioactive glass by clinically and radiographically in periodontal intrabony defects for a period of 12 months. Materials and Methods: Ten systemically healthy patients diagnosed with chronic periodontitis, with radiographic evidence of at least a pair of contralateral vertical osseous defects were included in this study. Defect on one-side is treated with DFDBA and the other side with bioactive glass. Clinical and radiographic measurements were made at baseline 6 month and 12 month after the surgery. Results: Compared to baseline, the 12 month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, probing depth, clinical attachment level (CAL and radiographic parameters (bone fill; P < 0.001FNx01. However, sites treated with DFDBA exhibited statistically significantly more changes compared to the bioactive glass in probing depth reduction (2.5 ± 0.1 mm vs. 1.8 ± 0.1 mm CAL gain 2.4 ± 0.1 mm versus 1.7 ± 0.2 mm; ( P < 0.001FNx01. At 12 months, sites treated with bioactive glass exhibited 56.99% bone fill and 64.76% bone fill for DFDBA sites, which is statistically significant ( P < 0.05FNx01. Conclusion: After 12 months, there was a significant difference between the two materials with sites grafted with DFDBA showing better reduction in probing pocket depth, gain in CAL and a greater percentage of bone fill when compared to that of bioactive glass.