-
Journal of Biomedical Materials... Mar 2019Incorporation of hydroxyapatite (HA) into polymer networks is a promising strategy to enhance the mechanical properties and osteoinductivity of the composite scaffolds...
Incorporation of hydroxyapatite (HA) into polymer networks is a promising strategy to enhance the mechanical properties and osteoinductivity of the composite scaffolds for bone tissue engineering. In this study, we designed a group of nanocomposite scaffolds based on cross-linkable poly(propylene fumarate) (PPF) and 30 wt % strontium-hydroxyapatite (Sr-HA) nanoparticles. Four different Sr contents [Sr:(Sr + Ca), molar ratio] in the Sr-HA particles were studied: 0% (HA), 5% (Sr5-HA), 10% (Sr10-HA), and 20% (Sr20-HA). Two-dimensional (2D) disks were prepared using a thermal crosslinking method. The structure and surface morphology of different Sr-HA and PPF/Sr-HA composites were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). To detect cellular responses in vitro, MC3T3-E1 cells were seeded and cultured on the different PPF/Sr-HA composite disks. Cell morphology after 24 h and 5 days were imaged using Live/Dead live cell staining and SEM, respectively. Cell proliferation was quantified using an MTS assay at 1, 4, and 7 days. Osteogenic differentiation of the cells was examined by alkaline phosphatase (ALP) staining at 10 days and quantified using ALP activity and osteocalcin assays at 7, 14, and 21 days. The sizes of the HA, Sr5-HA, Sr10-HA, and Sr20-HA particles were mainly between 10 × 20 nm and 10 × 250 nm, and these nanoparticles were dispersed or clustered in the composite scaffolds. in vitro cell studies showed that the PPF/Sr10-HA scaffold was significantly better than the other three groups (PPF/HA, PPF/Sr5-HA, and PPF/Sr20-HA) in supporting MC3T3-E1 cell adhesion, proliferation, and differentiation. PPF/Sr10-HA may, therefore, serve as a promising scaffold material for bone tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 631-642, 2019.
Topics: Animals; Cell Differentiation; Cell Line; Durapatite; Fumarates; Mice; Nanocomposites; Osteogenesis; Polypropylenes; Strontium; Tissue Scaffolds
PubMed: 30422387
DOI: 10.1002/jbm.a.36579 -
Journal of Biomaterials Science.... Apr 2017Polypropylene (PP) transvaginal mesh (TVM) repair for stress urinary incontinence (SUI) has shown promising short-term objective cure rates. However, life-altering...
Polypropylene (PP) transvaginal mesh (TVM) repair for stress urinary incontinence (SUI) has shown promising short-term objective cure rates. However, life-altering complications have been associated with the placement of PP mesh for SUI repair. PP degradation as a result of the foreign body reaction (FBR) has been proposed as a contributing factor to mesh complications. We hypothesized that PP oxidizes under in vitro conditions simulating the FBR, resulting in degradation of the PP. Three PP mid-urethral slings from two commercial manufacturers were evaluated. Test specimens (n = 6) were incubated in oxidative medium for up to 5 weeks. Oxidation was assessed by Fourier Transform Infrared Spectroscopy (FTIR), and degradation was evaluated by scanning electron microscopy (SEM). FTIR spectra of the slings revealed evidence of carbonyl and hydroxyl peaks after 5 weeks of incubation time, providing evidence of oxidation of PP. SEM images at 5 weeks showed evidence of surface degradation, including pitting and flaking. Thus, oxidation and degradation of PP pelvic mesh were evidenced by chemical and physical changes under simulated in vivo conditions. To assess changes in PP surface chemistry in vivo, fibers were recovered from PP mesh explanted from a single patient without formalin fixation, untreated (n = 5) or scraped (n = 5) to remove tissue, and analyzed by X-ray photoelectron spectroscopy. Mechanical scraping removed adherent tissue, revealing an underlying layer of oxidized PP. These findings underscore the need for further research into the relative contribution of oxidative degradation to complications associated with PP-based TVM devices in larger cohorts of patients.
Topics: Biocompatible Materials; Female; Humans; Materials Testing; Microscopy, Electron, Scanning; Oxidation-Reduction; Photoelectron Spectroscopy; Polypropylenes; Spectroscopy, Fourier Transform Infrared; Surgical Mesh
PubMed: 28081670
DOI: 10.1080/09205063.2017.1279045 -
Journal of Biomedical Materials... Nov 2017Recently, non-metal-clasp dentures (NMCDs) made from thermoplastic resins such as polyamide, polyester, polycarbonate, and polypropylene have been used as removable...
Recently, non-metal-clasp dentures (NMCDs) made from thermoplastic resins such as polyamide, polyester, polycarbonate, and polypropylene have been used as removable partial dentures (RPDs). However, the use of such RPDs can seriously affect various tissues because of their low rigidity. In this study, we fabricated high-rigidity glass-fiber-reinforced thermoplastics (GFRTPs) for use in RPDs, and examined their physical properties such as apparent density, dynamic hardness, and flexural properties. GFRTPs made from E-glass fibers and polypropylene were fabricated using an injection-molding. The effects of the fiber content on the GFRTP properties were examined using glass-fiber contents of 0, 5, 10, 20, 30, 40, and 50 mass%. Commercially available denture base materials and NMCD materials were used as controls. The experimental densities of GFRTPs with various fiber contents agreed with the theoretical densities. Dynamic micro-indentation tests confirmed that the fiber content does not affect the GFRTP surface properties such as dynamic hardness and elastic modulus, because most of the reinforcing glass fibers are embedded in the polypropylene. The flexural strength increased from 55.8 to 217.6 MPa with increasing glass-fiber content from 0 to 50 mass%. The flexural modulus increased from 1.75 to 7.42 GPa with increasing glass-fiber content from 0 to 50 mass%, that is, the flexural strength and modulus of GFRTP with a fiber content of 50 mass% were 3.9 and 4.2 times, respectively, those of unreinforced polypropylene. These results suggest that fiber reinforcement has beneficial effects, and GFRTPs can be used in NMCDs because their physical properties are better than those of controls. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2254-2260, 2017.
Topics: Dentures; Elastic Modulus; Glass; Hardness; Humans; Polycarboxylate Cement; Polyesters; Polypropylenes; Stress, Mechanical
PubMed: 27459321
DOI: 10.1002/jbm.b.33761 -
Cytotoxicity of polymers intended for the extrusion-based additive manufacturing of surgical guides.Scientific Reports May 2022Extrusion-based printing enables simplified and economic manufacturing of surgical guides for oral implant placement. Therefore, the cytotoxicity of a biocopolyester...
Extrusion-based printing enables simplified and economic manufacturing of surgical guides for oral implant placement. Therefore, the cytotoxicity of a biocopolyester (BE) and a polypropylene (PP), intended for the fused filament fabrication of surgical guides was evaluated. For comparison, a medically certified resin based on methacrylic esters (ME) was printed by stereolithography (n = 18 each group). Human gingival keratinocytes (HGK) were exposed to eluates of the tested materials and an impedance measurement and a tetrazolium assay (MTT) were performed. Modulations in gene expression were analyzed by quantitative PCR. One-way ANOVA with post-hoc Tukey tests were applied. None of the materials exceeded the threshold for cytotoxicity (< 70% viability in MTT) according to ISO 10993-5:2009. The impedance-based cell indices for PP and BE, reflecting cell proliferation, showed little deviations from the control, while ME caused a reduction of up to 45% after 72 h. PCR analysis after 72 h revealed only marginal modulations caused by BE while PP induced a down-regulation of genes encoding for inflammation and apoptosis (p < 0.05). In contrast, the 72 h ME eluate caused an up-regulation of these genes (p < 0.01). All evaluated materials can be considered biocompatible in vitro for short-term application. However, long-term contact to ME might induce (pro-)apoptotic/(pro-)inflammatory responses in HGK.
Topics: Gingiva; Humans; Keratinocytes; Polymers; Polypropylenes; Stereolithography
PubMed: 35513701
DOI: 10.1038/s41598-022-11426-y -
Macromolecular Bioscience Jun 2022Hernia repair mesh is associated with a number of complications, including adhesions and limited mobility, due to insufficient mechanical strength and nonresorbability....
Hernia repair mesh is associated with a number of complications, including adhesions and limited mobility, due to insufficient mechanical strength and nonresorbability. Among them, visceral adhesions are one of the most serious complications of patch repair. In this study, a degradable patch with an antiadhesive layer is prepared for hernia repair by 3D printing and electrospinning techniques using polycaprolactone, polyvinyl alcohol, and soybean peptide (SP). The study into the physicochemical properties of the patch is found that it has adequate mechanical strength requirements (16 N cm ) and large elongation at break, which are superior than commercial polypropylene patches. In vivo and in vitro experiments show that human umbilical vein endothelial cells proliferated well on composite patches, and showed excellent biocompatibility with the host and little adhesion through a rat abdominal wall defect model. In conclusion, the results of this study show that composite patch can effectively reduce the occurrence of adhesions, while the addition of SP in the patch further enhances its biocompatibility. It is believed that a regenerative biological patch with great potential in hernia repair provides a new strategy for the development of new biomimetic biodegradable patches.
Topics: Animals; Endothelial Cells; Herniorrhaphy; Polypropylenes; Rats; Surgical Mesh; Tissue Adhesions
PubMed: 35471592
DOI: 10.1002/mabi.202100510 -
Molecules (Basel, Switzerland) May 2022Plastic has made our lives comfortable as a result of its widespread use in today's world due to its low cost, longevity, adaptability, light weight and hardness;...
Plastic has made our lives comfortable as a result of its widespread use in today's world due to its low cost, longevity, adaptability, light weight and hardness; however, at the same time, it has made our lives miserable due to its non-biodegradable nature, which has resulted in environmental pollution. Therefore, the focus of this research work was on an environmentally friendly process. This research work investigated the decomposition of polypropylene waste using florisil as the catalyst in a salt bath over a temperature range of 350-430 °C. A maximum oil yield of 57.41% was recovered at 410 °C and a 40 min reaction time. The oil collected from the decomposition of polypropylene waste was examined using gas chromatography-mass spectrometry (GC-MS). The kinetic parameters of the reaction process were calculated from thermogravimetric data at temperature program rates of 3, 12, 20 and 30 °C·min using the Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunnose (KAS) equations. The activation energy (Ea) and pre-exponential factor (A) for the thermo-catalytic degradation of polypropylene waste were observed in the range of 102.74-173.08 kJ·mol and 7.1 × 10-9.3 × 10 min for the OFW method and 99.77-166.28 kJ·mol and 1.1 × 10-5.3 × 10 min for the KAS method at a percent conversion (α) of 0.1 to 0.9, respectively. Moreover, the fuel properties of the oil were assessed and matched with the ASTM values of diesel, gasoline and kerosene oil. The oil was found to have a close resemblance to the commercial fuel. Therefore, it was concluded that utilizing florisil as the catalyst for the decomposition of waste polypropylene not only lowered the activation energy of the pyrolysis reaction but also upgraded the quantity and quality of the oil.
Topics: Kinetics; Plastics; Polypropylenes; Pyrolysis; Thermogravimetry
PubMed: 35566367
DOI: 10.3390/molecules27093015 -
Journal of Environmental Science and... 2023As the carrier of various inorganics and organics from various media, micro(nano)plastics have an impact on the environment and human health. Recently, many studies have...
As the carrier of various inorganics and organics from various media, micro(nano)plastics have an impact on the environment and human health. Recently, many studies have examined the sorption of various organics including antibiotics. However, while vitamins have critical roles in the environment and microsystems from humans to plant life, the sorption of vitamins onto micro(nano)plastics are still uninvestigated. Therefore, the aim of this study was to examine the sorption of vitamin B1 onto various micro(nano)plastics from food packages under different pHs using batch technique; sorption kinetics and isotherms models were investigated as well. The results indicated that higher capacities were obtained between 360 min to 1440 min in polypropylene and polyethylene micro(nano)plastics, and similar kinetic behaviors observed in different pHs. However, the sorption responses (sorption capacity, equilibrium time) of polyethylene terephthalate and polystyrene were varied. The sorption kinetics between vitamin B1 and micro(nano)plastics showed that the pseudo-first-order model was better to fit for polyethylene terephthalate and polystyrene compared to the pseudo-second-order kinetics, however it was changed for polypropylene and polyethylene. Moreover, the obtained results suggest a complex nature of vitamin B1 sorption, including both chemical and physical sorption occur under various pHs and polymer types.
Topics: Humans; Plastics; Polystyrenes; Polypropylenes; Polyethylene Terephthalates; Thiamine; Polyethylene; Vitamins; Adsorption; Water Pollutants, Chemical; Kinetics
PubMed: 37272070
DOI: 10.1080/10934529.2023.2216123 -
Plant Physiology and Biochemistry : PPB Aug 2023Microplastics and di-2-ethylhexyl phthalate (DEHP) are prevalent and emerging pollutants in agro-ecosystem, raising concerns due to their widespread co-presence....
Microplastics and di-2-ethylhexyl phthalate (DEHP) are prevalent and emerging pollutants in agro-ecosystem, raising concerns due to their widespread co-presence. Nevertheless, their combined toxicity on terrestrial plants remains largely unexplored. This study investigated the impact of polypropylene microplastics (MPs), DEHP, and their mixture on the physiological and biochemical characteristics of cucumber seedlings. The changes of membrane stability index (MSI), antioxidase activities, photosynthetic pigments and chlorophyll fluorescence in cucumber seedlings were assessed. The results demonstrated that MPs alone significantly inhibited MSI, photosynthetic pigments (Chl a, Chl b, and Chl a + b), F and q of cucumber seedlings, and significantly promoted the carotene content and antioxidant enzyme activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) in cucumber seedlings. While DEHP alone significantly inhibited MSI and photosynthetic pigments of cucumber seedlings, and significantly promoted antioxidant enzyme activities in cucumber seedlings. Moreover, the combined toxicity of MPs and DEHP was found to be less pronounced than that of the single action of MPs and DEHP. The interaction between DEHP and MPs may contribute to the reduced toxicity. Abbott's modeling revealed that the combined toxicity systems were all antagonistic (RI < 1). Two-factor analysis and principal component analysis further confirmed that the treatment of MPs alone contributed the most to the toxicological effects of the physiological properties of cucumbers. In summary, this study highlighted the importance of understanding the combined effects of MPs and DEHP on plant physiology, providing insights for the development of effective treatments for emerging pollutants in agricultural ecosystems.
Topics: Cucumis sativus; Antioxidants; Microplastics; Plastics; Polypropylenes; Ecosystem; Diethylhexyl Phthalate; Seedlings; Environmental Pollutants
PubMed: 37307719
DOI: 10.1016/j.plaphy.2023.107811 -
Current Opinion in Urology Jul 2019To review the current clinical management of stress urinary incontinence and pelvic organ prolapse following the adverse complications seen in the use of polypropylene... (Review)
Review
PURPOSE OF REVIEW
To review the current clinical management of stress urinary incontinence and pelvic organ prolapse following the adverse complications seen in the use of polypropylene mesh to treat both.
RECENT FINDINGS
Materials developed for use in abdominal hernia repair have not proven risk-free when used to support pelvic organs particularly when inserted via the vagina. Following unacceptably high levels of severe complications when high-density polypropylene mesh is inserted via the vagina to treat pelvic organ prolapse, reported over the last decade, there is now an agreed consensus between surgeons about surgical approaches and materials, which should be recommended for use in stress urinary incontinence and pelvic organ prolapse.
SUMMARY
There is a need for new biomaterials and tissue engineered/regenerative medicine approaches to treat stress urinary incontinence and pelvic organ prolapse. New materials need to be evaluated critically in both preclinical and clinical studies before being adopted into routine clinical use.
Topics: Biocompatible Materials; Female; Humans; Pelvic Organ Prolapse; Polypropylenes; Prostheses and Implants; Risk Assessment; Surgical Mesh; Tissue Engineering; Urinary Incontinence, Stress; Vagina
PubMed: 30888974
DOI: 10.1097/MOU.0000000000000619 -
Bio-medical Materials and Engineering 2015To improve the biocompatibility of PP monofilaments used for pelvic reconstruction mesh, natural pearl powders were introduced as fillers in the preparation of modified...
To improve the biocompatibility of PP monofilaments used for pelvic reconstruction mesh, natural pearl powders were introduced as fillers in the preparation of modified PP monofilaments. The mechanical properties the modified PP monofilaments were analyzed, followed by characterization by scanning electron microscopy (SEM). Then, the biocompatibilities of these samples were investigated by MTT assay. The results revealed that the tensile strength and elongation of the as-prepared PP monofilaments can satisfy the requirement. According to the SEM images, masses of pearl powder were observed on the surface of monofilaments, which may favor the cell growth. The MTT results and the confocal microscopical images indicated that the presence of pearl powder in PP monofilaments led to improved proliferation and growth of L929 and PIEC cells under the same conditions, suggesting that PP monofilaments modified by pearl powders have a great potential in the applications of pelvic reconstruction.
Topics: Animal Shells; Animals; Biocompatible Materials; Cell Line; Cell Survival; Elastic Modulus; Endothelial Cells; Equipment Failure Analysis; Fibroblasts; Materials Testing; Mice; Pinctada; Polypropylenes; Powders; Prosthesis Design; Stress, Mechanical; Surgical Mesh; Swine; Tensile Strength; Tissue Scaffolds
PubMed: 26406012
DOI: 10.3233/BME-151286