Biomaterials For Construction Research Articles

Experimental evaluation of the synergistic effect of calcium precursor dosage and bacterial strain interactions on the biogenic healing potential of self-healing cement mortar

This study investigates the microbially induced calcium carbonate precipitation (MICP) in repair mortar, focusing on the impact of calcium precursor dosage and bacterial strain selection. C6H10CaO6·xH2O and (CH3COO)2Ca·xH2O were used as calcium precursors at dosages of 0.1, 0.25, and 0.4 M with Bacillus subtilis VEB4, Priestia megaterium TSB16, and Halobacillus halophilus MCC2188 microbes. Quantitative assessment of precipitate and optimization of precursor dosages were conducted before making mortar cube specimens of size 70.6 × 70.6 × 70.6 mm with bacterial spores and nutrients immobilized in Modified Expanded Perlite. Cracked cube specimens underwent automated wet-dry cycles of 12 h daily for 60 days to induce healing. Comparative analysis of biomortar specimens showed P. megaterium as the most effective in compressive strength recovery (up to 89.33%) and crack healing with a maximum healed crack width of 0.64 mm, followed by B. subtilis with significant CSR improvements. H. halophilus, less efficient in non-saline conditions, healed cracks up to 0.48 mm. Calcium lactate was considered the better calcium source choice for B. subtilis and P. megaterium strains, whereas calcium acetate improved MICP by H. halophilus. Microstructural analysis of healed precipitates collected from cracked cubes identified distinct morphology of MICP and the presence of polymorphs viz, calcite, aragonite, and vaterite. Tailored selection and dosage of calcium precursors for each strain significantly enhanced MICP and improved the quality of healing products in cracks, advancing the understanding of self-healing construction biomaterials.

Primary Ear Reconstruction Using Cadaveric Costal Cartilage.

Allogeneic cadaveric costal cartilage is commonly used for grafts in nasal reconstruction surgery; however, limited information exists on its use in total ear reconstruction for microtia. In this case series, we describe the novel use of cadaveric cartilage for auricular framework construction in ear reconstruction and review preliminary histologic findings. Patients requiring primary complete reconstruction of the auricle from August 2020 to December 2021 were eligible and underwent ear reconstruction using cadaveric costal cartilage. Patients were evaluated for surgical site infection, skin necrosis, cartilage resorption, and cartilage exposure during regular follow-up visits. Two cartilage samples were taken after 2 separate second-stage surgeries done 52 weeks after first-stage reconstruction. These samples were stained with hematoxylin and eosin as well as safranin-O and examined under light microscopy. A total of 12 ear reconstruction procedures using cadaveric costal cartilage were performed across 11 patients; 10 of 12 ears had type III microtia and 2 of 12 ears had type IV microtia. Patients ranged from 4 to 25 years old at the time of surgery, with an average age of 10.7 years. Follow-up time ranged from 1.6 to 25.4 months, with a mean follow-up time of 11.2 months. No patients experienced any visibly significant cartilage warping. Two patients experienced minor construct exposure, which were successfully salvaged. Two patients experienced surgical site infections, one lead to resorption requiring framework replacement. Preliminary histologic analysis of the 2 samples taken 1 year after implantation showed viable chondrocytes with no evidence of immunologic rejection or any local inflammation or host foreign body response. Cadaveric costal cartilage serves as a viable alternative to autologous cartilage and other alloplastic biomaterials for construction of auricular frameworks in primary microtia reconstruction. Resorption secondary to infection and construct exposure remain potential risks. Longer follow-up times and a larger sample size are needed for assessment of long-term efficacy.

Research progress of natural biomaterials for construction of tissue engineering cornea

Research progress of natural biomaterials for construction of tissue engineering cornea

Investigation of thermo-acoustic and mechanical performance of gypsum-plaster and polyester fibers based materials for building envelope

Investigation of thermo-acoustic and mechanical performance of gypsum-plaster and polyester fibers based materials for building envelope

A new area of ​​application and research in bio-processes: Biotechnologies in civil construction

Construction Biotechnology is a new scientific and engineering discipline that has been developing exponentially during the last decade. The main directions of this discipline are 1- the selection of adequate microorganisms, 2- development of micro-processed construction bioprocesses as well as 3- the development of new biotechnologies to produce construction biomaterials. Products resulting in construction biotechnologies are low-cost, sustainable, and environmentally friendly microbial biocements for the improvement of the construction terrain. The bioagents used in construction biotechnologies are pure or enrichment cultures of native microorganisms or microorganisms isolated and activated from the soil. Biotechnologically produced construction materials and microbial mediated construction technologies have many advantages compared to conventional construction materials and processes. The current technological landscape offers an objective vision and perspective of how microbes are used in the construction industry as additives for cement and concrete so that these new technologies be used in different provinces of Ecuador. In that sense, the current situation of cement and concrete production in Ecuador is briefly described to have an overview of the applicability of the new methods based on biogenic materials and the environmental advantages of the creation of construction biomaterials over conventional production.

SELECTION OF GROWTH SUBSTRATES FOR DEVELOPMENT NEW BIOMATERIALS USING MACROMYCETES PLEUROTUS OSTREATUS, PLEUROTUS ERYNGII AND GANODERMA LUCIDUM

The specific growth rates of Pleurotus ostreatus, Pleurotus eryngii and Ganoderma lucidum were determined on different culture media. Based on the data obtained, the optimal substrates were selected for the further production of artificial leather and construction biomaterials using fungal mycelium.

Scanning electron microscopy study of different one-piece foldable acrylic intraocular lenses after injection through microincisional cataract surgery cartridges.

To evaluate possible surface alterations of different models of one-piece foldable acrylic intraocular lenses (IOLs) after folding and ejecting process through 2.2-mm microincisional cataract surgery (MICS) cartridges. In this experimental laboratory study, the following IOLs were studied: Johnson&Johnson PCB00, HOYA iSert 251, Alcon AcrySof IQ SN60WF, Bausch&Lomb enVISTA MX-60. A total of 80 IOLs were analyzed. Twenty intraocular lenses of each type were studied: ten with a power of + 21 D ± 1 and ten with a power of + 28 D ± 1. IOLs were injected through a dedicated 2.2-mm MICS cartridge into a 50-mL vial containing 10mL of deionized water. After rinsing and metallization process, scanning electron microscopy images were acquired. All IOLs presented high-quality construction biomaterials. Some IOLs showed superficial scratches and tears on the optic surface, mainly positioned according to the direction of the stress induced by the folding process. In other cases, small superficial tears were seen in a more peripheral position. All lenses showed excellent surface quality. After folding and injection process some superficial scratches and tears of the IOL optic were detected in some models. Further studies are needed to assess the possible effects of those superficial damages on the optical quality of the IOLs.

Environmental safety and biosafety in construction biotechnology.

The topics of Construction Biotechnology are the development of construction biomaterials and construction biotechnologies for soil biocementation, biogrouting, biodesaturation, bioaggregation and biocoating. There are known different biochemical types of these biotechnologies. The most popular construction biotechnology is based on precipitation of calcium carbonate initiated by enzymatic hydrolysis of urea which follows with release of ammonia and ammonium to environment. This review focuses on the hazards and remedies for construction biotechnologies and on the novel environmentally friendly biotechnologies based on precipitation of hydroxyapatite, decay of calcium bicarbonate, and aerobic oxidation of calcium salts of organic acids. The use of enzymes or not living bacteria are the best options to ensure biosafety of construction biotechnologies. Only environmentally safe construction biotechnologies should be used for such environmental and geotechnical engineering works as control of the seepage in dams, channels, landfills or tunnels, sealing of the channels and the ponds, prevention of soil erosion and soil dust emission, mitigation of soil liquefaction, and immobilization of soil pollutants.

Cadherin-matrix engineering for homogeneous reaction control of ES/iPS/Stem Cells

Event Abstract Back to Event Cadherin-matrix engineering for homogeneous reaction control of ES/iPS/Stem Cells Toshihiro Akaike1 1 Foundation for Advancement of International Science, Biomaterials Center for Regenerative Medical Engineering, Japan Recently, embryonic stem (ES) and induced pluripotent stem (iPS) cells have shown remarkable potential to treat human diseases. Biomaterials are rapidly being developed as powerful artificial microenvironments to study and control stem-cell fate, such as proliferation and differentiation. Our recent advances include biomaterial-based artificial extracellular matrix formed by immobilizing cell-recognizable molecule, growth factors and cytokines. Here, we propose “Cadherin-Matrix Engineering” for new frontier of cell-recognizable biomaterials for construction of “Cell-cooking plate” for ES/iPS cells technology using chimeric proteins of cell adhesion molecules (e.g., E-cadherin, N-cadherin, or VE-cadherin). Our novel E-cadherin-based engineered extracellular matrix showed fascinating results: (1) highly homogeneous differentiation of definitive endoderm cells under single-cell level; (2) uniform distribution of growth factors resulted in con differentiation even in lower concentration of free culture due to the absence of serum and feeder layers; (3) completely defined and xeno- short period of differentiation; (4) highly functional hepatocytes within soluble factors; (5) striking effect of matrix-dependent cell sorting for isolation and enrichment of mature hepatocytes for possible elimination of contaminated and poorly differentiated cells; (6) the unique opportunity for continuous monitoring of cellular behavior in different stages of differentiation. Taken together, our novel recombinant ECM is advantageous for generating homogeneous population of differentiated cells without any enzymatic stress and cell sorting, suggesting that the improved method of differentiation is highly promising for clinically significant adult cells (hepatocytes, neural cells, cardiomyocytes, pancreatic cells and the likes ). We established a novel biomedical field in applied cadherin biology named as “Cadherin-Matrix Engineering” which can be applied to “Cell-cooking Plate” for ES/iPS and other stem cells in regenerative medicine. Keywords: Cell Differentiation, Extracellular Matrix, Regenerative Medicine, biomimetic culture Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Biomaterials and cellular signaling Citation: Akaike T (2016). Cadherin-matrix engineering for homogeneous reaction control of ES/iPS/Stem Cells. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.00223 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 28 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Toshihiro Akaike Google Toshihiro Akaike Google Scholar Toshihiro Akaike PubMed Toshihiro Akaike Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Dynamic and static tensile mechanical properties of myocardial tissue.

Event Abstract Back to Event Dynamic and static tensile mechanical properties of myocardial tissue. Sherif Ramadan1, 2, 3, Hani Naguib1, 2, 3 and Narinder Paul3, 4 1 University of Toronto, Mechanical and Industrial Engineering, Canada 2 University of Toronto, Smart and Adaptive Polymers Lab, Canada 3 University of Toronto, Institute of Biomaterials and Biomedical Engineering, Canada 4 Toronto General Hospital, Joint Department of Medical Imaging, Canada Introduction: Heart disease is a significant cause of morbidity and mortality that affects 1.3 million Canadians annually[1]. Coronary artery disease (CAD) is a leading cause of heart disease and is due to progressive accumulation of arterial plaque resulting in occlusion of the arterial lumen and abnormal myocardial contractility[2]. Computed Tomography Coronary Angiography (CTCA) is used to exclude significant CAD in patients with low-intermediate pre-test probability[3],[4]. However, dynamic anthropomorphic CT phantom devices that realistically mimic normal and diseased cardiac tissues are required to test new imaging techniques and algorithms that target ultralow radiation dose and high resolution CTCA. This study aims to quantify the mechanical properties of myocardial tissue to allow for the fabrication of phantoms that mimic the behaviour of heart tissue under varying hemodynamic conditions. Materials and Methods: The elasticity of myocardial tissue was tested under static and dynamic conditions. Tensile testing was performed to obtain the Young’s modulus and a dynamic mechanical analyzer (DMA) induced a frequency sweep to determine the complex (dynamic) modulus. A frequency range of 0.5Hz to 3.5Hz was analyzed as these frequencies correspond to human heart rates of 30 to 210bpm. Multiple tissue samples were taken from each pig and lamb heart, these animal models were chosen as they are close human analogues and are commonly used as replacements for human tissue[5],[6].The heart tissue was tested while freshly sacrificed without any intervening freeze-thaw cycles to ensure the integrity of the muscle tissue. The tissue was placed in a balanced salt solution and tested at 37°C to simulate in vitro conditions[7]. Results and Discussion: Preliminary data (mean ± SD): The tensile and complex moduli were tested on 6 pig and lamb hearts; tensile modulus of lamb = 0.06 ±0.03 (n=15 samples) and for pig =0.04 ± 0.03 (n=11 samples); the complex modulus for lamb = 0.03Mpa at 0.5Hz to 0.06 Mpa at 3.5Hz ± 0.02 (n=15 samples) and for pig = 0.03Mpa at 0.5Hz to 0.06 Mpa at 3.5Hz ± .01 (n=15 samples) and both exhibited a linear trend. These values indicate that myocardial tissue behaves similarly to soft rubbers and stiffens under higher frequency loads. Moreover, for tensile testing there was no statistical difference between individual hearts or animals (P values of 0.235, 0.483, and 0.73 between the animals, pig hearts, and lamb hearts respectively). Conclusions: The static and dynamic moduli of myocardial tissue in pig and lamb hearts is between 0.02 and 0.1Mpa which is similar to soft, rubber-like materials. This quantitative data will inform selection and fabrication of customized biomaterials for construction of the myocardium in a dynamic anthropomorphic tissue realistic heart phantom.

Construction Biotechnology: a new area of biotechnological research and applications.

A new scientific and engineering discipline, Construction Biotechnology, is developing exponentially during the last decade. The major directions of this discipline are selection of microorganisms and development of the microbially-mediated construction processes and biotechnologies for the production of construction biomaterials. The products of construction biotechnologies are low cost, sustainable, and environmentally friendly microbial biocements and biogrouts for the construction ground improvement. The microbial polysaccharides are used as admixtures for cement. Microbially produced biodegradable bioplastics can be used for the temporarily constructions. The bioagents that are used in construction biotechnologies are either pure or enrichment cultures of microorganisms or activated indigenous microorganisms of soil. The applications of microorganisms in the construction processes are bioaggregation, biocementation, bioclogging, and biodesaturation of soil. The biotechnologically produced construction materials and the microbially-mediated construction technologies have a lot of advantages in comparison with the conventional construction materials and processes. Proper practical implementations of construction biotechnologies could give significant economic and environmental benefits.

Engineered Biomaterials for Construction: A Cradle-to-Cradle Design Methodology for Green Material Development

AbstractMaterials used in a sustainable building application must have low (or zero) embodied energy in order to contribute to the elemental objective in minimizing total carbon footprint. Traditional construction materials are primarily derived and manufactured using nonrenewable resources and, at the end of their useful lives, typically disposed of in landfills where they lie recalcitrant. To address this cradle-to-grave concern in material manufacture, use, and disposal, novel construction materials are being developed with a target of relying only on rapidly renewable resources, including waste streams. The proposed cradle-to-cradle biomaterials are fabricated by using natural fibers as reinforcement in a biodegradable polymeric matrix derived from polyhydroxyalkanoates (PHAs), naturally occurring aliphatic thermoplastic polyesters produced by microbes via bacterial fermentation in carbon-rich environments. The composite material produced exhibits comparable material properties to structural grade wood and is rapidly biodegradable in specific anaerobic conditions at the end of its useful life. Using anaerobic digester sludge from local wastewater treatment plants as the biodegradation medium, the material decomposes into biogas that consists mostly of inert gases and, of particular interest, methane, which can be captured and used either as a biofuel or as a closed-loop carbon source for the production of new PHAs. This paper documents biobased composite material development, durability issues, anaerobic biodegradation, and potential industrial applications.