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Key Clinical Message: In the anatomically complex terrain of the head and neck, the use of 3D intraoperative models serves as an effective verification tool, determining the size, shape, and number of foreign bodies. This allows the main operator to maximize their capacities for careful wound revision and receive real-time information about the remaining content of the sought-after bodies. Abstract: Penetrating foreign bodies of various origins in the head and neck are uncommon, but potentially hazardous injuries. Complete removal of foreign bodies from soft tissues is essential for optimal healing, minimizing complications, and significantly reducing the risk of the need for reoperation. Despite various technological systems and safeguards available, unintentionally retained surgically placed foreign bodies remain difficult to eliminate completely. A 34-year-old female patient with a cut on the right side of her face who was initially treated with sutures at a general surgical clinic presented for a follow-up examination. A foreign body was verified subcutaneously on the anterior-posterior x-ray image on the right side. Computed tomography confirmed a total of 7 foreign bodies with a density corresponding to dental enamel, distributed subcutaneously, subfascially, and intramuscularly in the right temporal region. As part of the preoperative preparation and analysis, the bone segment of the right temporal fossa with the zygomatic bone and the glass fragments were segmented from the CT data and printed on an SLA printer. The physical 3D models were autoclave sterilized and present during surgery. The position, shape, and number of each individual glass fragment was compared with 3D-printed one. The benefits of producing 3D models of foreign bodies are undeniable, particularly in their perioperative comparison with the removed foreign bodies from wounds.

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In this investigation, composite poly(lactic acid) (PLA) systems of hollow glass microspheres (MS) and carbonyl iron particles (CIP) were processed and characterized to investigate the effects of using conductive and insulating particles as additives in a polymer system. PLA-MS and PLA-CIP were set at the two levels of 3.94 and 7.77 vol.% for each particle type to study the effects of the particle material type and loading on neat PLA's thermal properties. It was observed during the twin-screw extrusion that the addition of CIP greatly decreased the viscosity of the PLA melt during processing. Correlations determined using thermogravimetric analysis, differential scanning calorimetry, thermal conductivity, and shear rheology provided insights into how thermal stability was affected. The incorporation of MS and CIP altered thermal properties such as the glass transition temperature (Tg), melting temperature (Tm), and cold crystallization temperature (Tcc). The metal CIP-filled systems had large increases in their thermal conductivity values and viscoelastic transitions compared to those with PLA that were correlated with the observed overheating during extrusion.

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Lentzea aerocolonigenes, as an actinomycete, is a natural producer of the antibiotic and antitumoral drug rebeccamycin. Due to the filamentous cellular morphology handling in cultivations is challenging; therefore, morphology engineering techniques are mandatory to enhance productivity. One promising approach described in the literature is the addition of mineral particles in the micrometer range to precisely adjust cellular morphology and the corresponding product synthesis (microparticle-enhanced cultivation, MPEC). Glass microparticles are introduced in this study as a novel supplementation type for bioprocess intensification in filamentous organisms. Several investigations were conducted to screen for an optimal particle setup, including particle size and concentration regarding their impact and effects on enhanced productivity, microparticle incorporation behavior into the biopellets, the viability of pellets, and morphological changes. Glass microparticles (10 g·L-1) with a median diameter of 7.9 µm, for instance, induced an up to fourfold increase in product synthesis accompanied by overall enhanced viability of biomass. Furthermore, structural elucidations showed that biopellets isolated from MPEC tend to have lower hyphal density than unsupplemented control pellets. In this context, oxygen microprofiling was conducted to better understand how internal structural changes interwind with oxygen supply into the pellets. Here, the resulting oxygen profiles are of a contradictive trend of steeper oxygen consumption with increasing glass microparticle supplementation. Eventually, MPEC was combined with another promising cultivation strategy, the supplementation of soy lecithin (7.5 g·L-1), to further increase the cultivation performance. A combination of both techniques in an optimized setup resulted in a rebeccamycin concentration of 213 mg·L-1 after 10 days of cultivation, the highest value published so far for microparticle-supplemented shake flask cultivations of L. aerocolonigenes.

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Selective internal radiation therapy (SIRT) is a treatment which delivers radioactive therapeutic microspheres via the hepatic artery to destroy tumorigenic tissue of the liver. However, the dose required varies significantly from patient to patient due to nuances in individual biology. Therefore, a positron emission tomography (PET) imaging surrogate, or radiotracer, is used to predict in vivo behavior of therapeutic Y-90 spheres. The ideal surrogate should closely resemble Y-90 microspheres in morphology for highest predictive accuracy. This work presents the fabrication of positron-emitting silica microspheres infused with PET radiotracers copper, fluorine, and gallium. A quick one-pot synthesis is used to create precursor sol, followed by droplet formation with flow-focusing microfluidics, and finally thermal treatment to yield 10-50 µm microspheres with narrow size distribution. Loading of the infused element is controllable in the sol synthesis, while the final sphere size is tunable based on microfluidic flow rates and device channel width. The system is then employed to make radioactive Ga-68 microspheres, which are tested for radioactivity and stability. The fabrication method can be completed within a few hours, depending on the desired microsphere quantity. A microfluidic system is applied to fabricate silica particles loaded with diverse elemental infusions, including radioactive Ga-68.

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Nasal cavity tumors constitute a very small part of head and neck malignancies. Although paranasal sinus tumors due to the presence of backward foreign bodies, neoplasms of nasal cavity associated with a foreign body are extremely rare. In this article, we presented a rare case of carcinoma in the right nasal cavity which includes glass particles inside it, and the role of glass particles in carcinogenesis was discussed. The patient was a 55-year-old male with history of a car accident 30 years ago. During right medial maxillectomy via a right lateral rhinotomy approach, three pieces of glass beads, approximately 0.5 cm in size, were removed from the inside of the mass. The patient had also under gone postoperative radiotherapy. No complication emerged during the postoperative recovery period. The patient had been followed up with no finding of local recurrence for 12 months.

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An effective strategy of hyperthermia-chemotherapy-regeneration for bone-related cancer treatment is presented. For this purpose, a new approach of magnetic particles (MPs) encapsulated in bioactive glass (BG) structure, with anti-cancer activity, is evaluated. MPs are initially synthesized using a co-precipitation method and then embedded into BG structure through a sol-gel synthesis process. Results confirmed the formation of a crystalline and pure MP structure. MP-BG particles were found to be bioactive by forming a hydroxyapatite layer on their surface. The hyperthermia application of a MP-BG system was also studied. It was found that the particles reach a temperature of 42 °C in an alternating magnetic field. Doxorubicin (DOX), a widely used anticancer drug, was loaded in MP-BG. To enhance the loading efficiency, the BG was surface modified to create NH2groups on the surface. The encapsulation and release of DOX was studied over 48 h.In vitrotests were performed using human osteosarcoma cell line (MG63). The results demonstrated the non-cytotoxic nature of MP and MP-BG tested at various concentrations. DOX release from MP-BG resulted in decreased MG63 viability. Also, fluorescence microscopy visualization confirmed the intracellular uptake of MP-BG particles and the release of DOX. These results indicate that our suggested strategy of combined hyperthermia-chemotherapy-regeneration using MP-BG structure represents a powerful approach in cancer treatment and tissue regeneration.

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Biodegradable polymer scaffolds filled with bioactive glass particles doped with therapeutic metal ions are a novel and promising strategy to repair critical-sized bone defects. In this study, scaffolds based on a poly (D, L-lactide acid) (PDLLA) matrix filled with un-doped and Cu-, Zn- and CuZn-doped bioactive glass particles were produced by freeze-drying and a salt-leaching method. The effects of the doping and content of the glass particles (10 and 30 wt.%) on the morphology, compression properties, apatite formation, and degradation behavior of the scaffolds were evaluated. The scaffolds presented high porosity (~93%) with pores ranged from 100 to 400 µm interconnected by smaller pores and this porosity was kept after the glass particles incorporation. The glass particles reinforced the polymer scaffolds with improvements as high as 130% in elastic moduli, and further promoted the apatite formation on the scaffold surface, both properties depending on the amount and type of filler. The bioactive glass particles boosted the scaffold degradation with the PDLLA/un-doped glass scaffold showing the highest rate, but still retaining structural and dimensional integrity. Our findings show that the incorporation of un-doped and metal-doped bioactive glasses increases the mechanical strength, promotes the bioactivity and modifies the degradation profile of the resulting polymer/glass scaffolds, making them better candidates for bone repair.

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Osteoconductive hydrogels can be fabricated by incorporating necessary growth factors and bioactive particles or simply utilizing the ability of the hydrogel itself to induce bone regeneration. The osteogenic inductive potential of the bioactive glass microparticles (BG MPs) has been well-studied. However, the role of the hydrogel embedding the BG MPs on the osteogenic differentiation of the encapsulated stem cells has not been well established. Moreover, it has been reported that the dental pulp stem cell (DPSC) has the capability of regenerating the craniofacial bone tissue when receiving the necessary osteogenic signals from the microenvironment. In the current study, we have fabricated a composite hydrogel based on alginate and Matrigel containing BG MPs and evaluated the role of the BG MPs and Matrigel on osteogenic differentiation of the encapsulated DPSCs. Our results confirmed that presence of Matrigel enhances the osteogenic differentiation of the DPSCs regardless of the decrease in elasticity of the hydrogel in presence of the BG MPs. This strategy of modifying the microenvironment can be a promising approach for craniofacial bone tissue engineering.

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In this study, mesoporous bioactive glass (MBG) sub-micro particles were prepared through sol-gel synthesis and possessed a uniform and spherical structure with particle size of 302 ±â€¯43 nm, a pore size of 4 nm and a high surface area of 354 m2 g-1. Alendronate (AL) is often used for the treatment of bone associated diseases, in particular osteosarcoma. However, due to the low bioavailability and high toxicity at increased doses, local and sustained release would be an ideal approach to AL delivery. Here, MBGs and aminated MBGs (AMBG) were applied as carriers for AL loading. High encapsulation efficiency of 75% and 85% and loading efficiency of 60% and 63%, for MBG and AMBG, respectively, was achieved. The release profile of AL from AMBG showed a better sustained and controlled release mechanism compared to MBG. In vitro results demonstrated the non-cytotoxic nature of both MBG and AMBG following exposure to MG63 osteoblast like cell line. AL release from MBG and AMBG, even at lower concentration, provoked decreased MG63 proliferation. The osteogenic potential of MBG and AMBG following exposure to dental pulp stem cells was evaluated using alizarin red assay.

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Metal matrix syntactic foams have been fabricated via counter-gravity infiltration of a packed bed of recycled expanded glass particles (EG) with A356 aluminum alloy. Particle shrinkage was studied and has been utilized to increase the particles' strength and tailor the mechanical properties of the expanded glass/metal syntactic foam (EG-MSF). The crushing strength of particles could be doubled by shrinking them for 20 min at 700 °C. Owing to the low density of EG (0.20-0.26 g/cm³), the resulting foam exhibits a low density (1.03-1.19 g/cm³) that increases slightly due to particle shrinkage. Chemical and physical analyses of EG particles and the resulting foams were conducted. Furthermore, metal syntactic foam samples were tested in uni-axial compression tests. The stress-strain curves obtained exhibit three distinct regions: elastic deformation followed by a stress plateau and densification commencing at 70-80% macroscopic strain. Particle shrinkage increased the mechanical strength of the foam samples and their average plateau stress increased from 15.5 MPa to 26.7 MPa.

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The health effects of silica may depend on the inherent properties of crystalline silica or on external factors affecting the biological activity or distribution of its polymorphs. Inhaled crystalline silica is classified as a Group I carcinogen, however, information on the health effects of amorphous silica is still insufficient. Considering that alveolar macrophages play a key role in both innate and adaptive immune responses for removal of foreign bodies that enter via the respiratory system, we treated sheet-like glass particles (SGPs), a type of noncrystalline amorphous silica, to MH-S cells, an alveolar macrophage cell line. SGPs reduced the generation of ROS and NO and induced cell death via multiple pathways. Although the expression of CD80, CD86, and CD40, increased by exposure to SGPs, the expression of MHC class II molecules had not notably changed. Additionally, expression of ICAM-1 tended to decrease. In mice, SGPs were distributed in the interstitial region of the lung without notable pathological lesion on day 14 after a single intratracheal instillation. Pulmonary total cell number increased significantly with the highest dose, but the levels of all measured inflammatory cytokines and chemokines, except IL-1, were lower in BAL fluid from SGP-treated mice compared to control. More interestingly, the expression of antigen presentation-related proteins was enhanced in the lungs of SGP-exposed mice concomitant with an increase in the number of mature dendritic cells, whereas the expression of ICAM-1, an important adhesion molecule for helper T cell recruitment, was suppressed. Taken together, we suggest that SGPs may induce adverse health effects by down-regulating function of immune cells in the lungs. Furthermore, ICAM-1 may play a key role in immune response to remove pulmonary SGPs.

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Mechanical properties of a scaffold play an important role in its in vivo performance in bone tissue engineering, due to the fact that implanted scaffolds are typically subjected to stress including compression, tension, torsion, and shearing. Unfortunately, not all the materials used to fabricate scaffolds are strong enough to mimic native bones. Extensive research has been conducted in order to increase scaffold strength and mechanical performance by incorporating nanoparticles and/or coatings. An incredible improvement has been achieved; and some outstanding examples are the usage of nanodiamond, hydroxyapatite, bioactive glass particles, SiO2, MgO, and silver nanoparticles. This review paper aims to present the results, to summarize significant findings, and to give perspective for future work, which could be beneficial to future bone tissue engineering.

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Sol-gel derived bioactive glass (BG) holds great potential in the application of skin repair. However, the specific regulation of BG on skin cells is still unclear and demands more investigation. Herein, we synthesized sol-gel derived BGs with different compositions (60S, 70S, 80S, and 90S) and found 90S BGs (90 mol % SiO2 , 6 mol % CaO, 4 mol % P2 O5 ) exhibited the best supportiveness for the proliferation of normal human foreskin fibroblasts. Thus, 90S BG particles were used as a model to systematically study the wound healing related cellular response of fibroblasts to BGs. Time-lapse imaging revealed a promoted fibroblast motility stimulated by 90S BG particles. Results on the expression of extracellular matrix (ECM) related genes illustrated that 90S BG particles modulated the synthesis capacity for critical ECM molecules including type I collagen, type III collagen, fibronectin, and tenascin-C. Moreover, the myofibroblastic differentiation of fibroblasts was greatly inhibited by 90S BG particles. Further analysis on the intracellular signaling pathways demonstrated that 90S BG particles down-regulated the collagen synthesis and fibroblast-to-myofibroblast differentiation via TGF-ß1-Smad2 signaling, evidenced by the decreased expression levels of TGF-ß receptor I and its downstream effector Smad2. Our study provided a further understanding of the specific regulation of 90S BG particles on fibroblasts, which may guide the future design of BG based wound dressing and benefit the clinical application of BG particles in skin repair. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2420-2429, 2016.

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UNLABELLED: One major current challenge facing companies producing injectable drugs contained in glass vials is the phenomenon of delamination that results in drug contamination. Particulate contamination of parenteral fluids is a fact of life. Particulate infusion is unlikely to cause immediate or severe signs and symptoms, but adverse effects, tissue damage, and loss of function are likely in the long term. Since 2010, recalls due to glass delamination have increased, and recently the U.S. Food and Drug Administration exercised temporary regulatory flexibility by allowing filtration as means of removing glass particles. The vial adapter is a needle-free product from West Pharmaceuticals Services that provides a simple and cost-effective solution for the safe and rapid transfer reconstitution of drugs between vials and syringes. One variant of the vial adapter is integrated with a filter to address various types of particles. In the present study, the performance of the filter-integrated vial adapter is evaluated with respect to glass delamination particles. Silica particles of 0.5-10 µm are used to emulate glass delamination particles. High-filtration efficiency is demonstrated according to the severest criteria stated by the British Pharmacopoeia that allows up to 100 particles smaller than 5 µm for every 1 mL liquid of a large-volume parenteral. The study was conducted using environmental scanning electron microscopy and statistical analysis. LAY ABSTRACT: One major current challenge facing companies producing injectable drugs contained in glass vials is the phenomenon of delamination that results in drug contamination. Glass delamination is defined as degradation of surface glass, as from a vial, that produces glass flakes. Contamination of injectable drugs due to glass delamination is a fact of life. Normally, this type of contamination does not involve immediate severe signs, but rather accumulative damage to tissues in the long run. Recently, the U.S. Food and Drug Administration allowed the filtration as means of removing particles. The vial adapter is a needle-free product from West Pharmaceuticals Services that provides a simple and cost-effective solution for the safe and rapid transfer reconstitution of drugs between vials and syringes. One variant of the vial adapter is integrated with a filter to address various types of particles. In the present study, the performance of the filter-integrated vial adapter is evaluated with respect to glass delamination particles. Silica particles of 0.5-10 µm are used to emulate glass delamination particles. High-filtration efficiency is demonstrated according to the severest criteria stated by the British Pharmacopoeia that allows up to 100 particles smaller than 5 µm for every 1 mL liquid of a large-volume parenteral. The study was conducted using environmental scanning electron microscopy and statistical analysis.

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