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Maxillary sinus retention cysts (MRCs) are typically asymptomatic and require no treatment. An early 30s man presented with a decade-long history of severe left-sided chronic facial pain (CFP). Multiple prior treatments resulted in an edentulous patient with persistent pain. Imaging revealed a dome-shaped radiopaque change in the left maxillary sinus. History and clinical examination suggested persistent idiopathic facial pain, and doubts about the outcome of a surgical intervention were explained to the patient. Surgical removal of the MRC via lateral antrotomy led to complete symptom resolution of CFP. This case substantiates the importance of considering MRCs as a possible cause of CFP. It also emphasises the need for a systematic multidisciplinary approach in cases of unexplained CFP., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

In this work, fully polysaccharide based membranes were presented as self-standing, solid polyelectrolytes for application in anion exchange membrane fuel cells (AEMFCs). For this purpose, cellulose nanofibrils (CNFs) were modified successfully with an organosilane reagent, resulting in quaternized CNFs (CNF (D)), as shown by Fourier Transform Infrared Spectroscopy (FTIR), Carbon-13 (C13) nuclear magnetic resonance ( 13 C NMR), Thermogravimetric Analysis (TGA)/Differential Scanning Calorimetry (DSC), and ζ-potential measurements. Both the neat (CNF) and CNF(D) particles were incorporated in situ into the chitosan (CS) membrane during the solvent casting process, resulting in composite membranes that were studied extensively for morphology, potassium hydroxide (KOH) uptake and swelling ratio, ethanol (EtOH) permeability, mechanical properties, ionic conductivity, and cell performance. The results showed higher Young's modulus (119%), tensile strength (91%), ion exchange capacity (177%), and ionic conductivity (33%) of the CS-based membranes compared to the commercial Fumatech membrane. The addition of CNF filler improved the thermal stability of the CS membranes and reduced the overall mass loss. The CNF (D) filler provided the lowest (4.23 × 10 -5 cm 2 s -1 ) EtOH permeability of the respective membrane, which is in the same range as that of the commercial membrane (3.47 × 10 -5 cm 2 s -1 ). The most significant improvement (~78%) in power density at 80 °C was observed for the CS membrane with neat CNF compared to the commercial Fumatech membrane (62.4 mW cm -2 vs. 35.1 mW cm -2 ). Fuel cell tests showed that all CS-based anion exchange membranes (AEMs) exhibited higher maximum power densities than the commercial AEMs at 25 °C and 60 °C with humidified or non-humidified oxygen, demonstrating their potential for low-temperature direct ethanol fuel cell (DEFC) applications.

Sedimentation is a naturally occurring process of allowing particles in water bodies to settle out of the suspension under a gravity effect. In this study, the sediments of the Drava River were fully investigated to determine the heavy metal concentrations along the river and their potential reuse in the construction sector. Naturally dehydrated sediments from the Drava River were tested as an additive for the production of fired bricks. The dredged sediments were used as a substitute for natural brick clay in amounts up to 50% by weight, and it was confirmed that up to 20% by weight of the added sediment could be used directly in the process without critically affecting performance. Finally, the naturally dehydrated sediments were also evaluated for their use as a filling material in the construction of levees. The natural moisture content of the dehydrated sediment was too high for it to be used without additives, so quicklime was added as an inorganic binder. The test results showed an improvement in the geotechnical properties of the material to such an extent that it is suitable as a filling material for levees.

Herein, we prepared a series of nanocomposite membranes based on chitosan (CS) and three compositionally and structurally different N-doped graphene derivatives. Two-dimensional (2D) and quasi 1D N-doped reduced graphene oxides (N-rGO) and nanoribbons (N-rGONRs), as well as 3D porous N-doped graphitic polyenaminone particles (N-pEAO), were synthesized and characterized fully to confirm their graphitic structure, morphology, and nitrogen (pyridinic, pyrrolic, and quaternary or graphitic) group contents. The largest (0.07%) loading of N-doped graphene derivatives impacted the morphology of the CS membrane significantly, reducing the crystallinity, tensile properties, and the KOH uptake, and increasing (by almost 10-fold) the ethanol permeability. Within direct alkaline ethanol test cells, it was found that CS/N rGONRs (0.07 %) membrane (P max . = 3.7 mWcm -2 ) outperformed the pristine CS membrane significantly (P max . = 2.2 mWcm -2 ), suggesting the potential of the newly proposed membranes for application in direct ethanol fuel cells.

The use of biomass to produce value-adding materials is a core objective of the circular economy, which has attracted great research interest in recent decades. In this context, we present here a simple dispersion-casting process for consolidation of cellulose nanofibrils (CNF), lignosulphonate (LS)-rich bio-waste and CaCl 2 in composite membranes. The addition of CaCl 2 to CNF and LS dispersions reduces the ζ potential, due to an electrostatic screening, which promotes the aggregation of CNF, increases its moisture content and promotes LS deposition on CNFs already in the dispersion phase. Addition of both the LS and CaCl 2 to CNF dispersion has an adverse effect on the mechanical properties of the final membranes. The effectiveness of the new composite membranes has been described in terms of their passive (charring) flame retardancy and 100 % UVA/UVB shielding capacity, both identified for membranes with the highest LS content, as well as high electronic resistance., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This work describes the derivatization of dextran using N-(tert-butyloxycarbonyl)-S-(trityl)-L-cysteine in the presence of N,N'-carbonyldiimidazole (CDI) as a coupling agent. Homogeneous reactions in dimethyl sulfoxide allowed for an efficient coupling of the amino acid derivative to the polymer backbone. Derivatization was confirmed by infrared and 13 C NMR spectroscopy, size exclusion chromatography and elemental analysis. The presence of hydrophobic protecting groups resulted in a product that can be shaped into water-insoluble particles stable in an aqueous environment and non-toxic for lung epithelial cells. It is suggested that materials composed of ester bonds between amino acids and polysaccharides are useful for targeted drug delivery, bio-imaging or surface functionalization., (Copyright © 2019. Published by Elsevier B.V.)

Schwannoma, neurilemmoma or neurinoma is a rare, benign nerve sheath neoplasm composed of Schwann cells. It is usually solitary, slow growing and asymptomatic. Approximately 1-12% of the tumours occur intraorally with the tongue being the most common location. We report a rare case of lingual schwannoma in a 20-year-old female patient involving the tip of the tongue, which was slow growing and asymptomatic. For diagnosis histopathological examination and also immunohistochemistry testing were carried out to confirm the nature of tissue fragments. The treatment was complete surgical excision., Competing Interests: Conflicts of Interest: None declared., (2016 BMJ Publishing Group Ltd.)

Hydrogels offer several advantages as biomaterials for bone regeneration, including ease of incorporation of soluble substances such as mineralization-promoting enzymes and antibacterial agents. Mineralization with calcium phosphate (CaP) increases bioactivity, while antibacterial activity reduces the risk of infection. Here, gellan gum (GG) hydrogels were enriched with alkaline phosphatase (ALP) and/or Seanol(®), a seaweed extract rich in phlorotannins (brown algae-derived polyphenols), to induce mineralization with CaP and increase antibacterial activity, respectively. The sample groups were unmineralized hydrogels, denoted as GG, GG/ALP, GG/Seanol and GG/Seanol/ALP, and hydrogels incubated in mineralization medium (0.1 M calcium glycerophosphate), denoted as GG/ALP_min, GG/Seanol_min and GG/Seanol/ALP_min. Seanol(®) enhanced mineralization with CaP and also increased compressive modulus. Seanol(®) and ALP interacted in a non-covalent manner. Release of Seanol(®) occurred in a burst phase and was impeded by ALP-mediated mineralization. Groups GG/Seanol and GG/ALP/Seanol exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. GG/Seanol/ALP_min, but not GG/Seanol_min, retained some antibacterial activity. Eluates taken from groups GG/ALP_min, GG/Seanol_min and GG/ALP/Seanol_min displayed comparable cytotoxicity towards MG-63 osteoblast-like cells. These results suggest that enrichment of hydrogel biomaterials with phlorotannin-rich extracts is a promising strategy to increase mineralizability and antibacterial activity.

Fusing multiwall carbon nanotubes (MWCNTs) with TiO2 at the nano-scale level promotes the separation of those electron-hole charges generated upon UV and daylight irradiation. In this study, we investigated facile sonochemical synthesis, combined with the calcination process for the preparations of TiO2-MWCNT composites with different mole ratios of titanium and carbon. In order to produce stable nano dispersions we exploited an innovative biotechnology-based approach for the covalent functionalizations of TiO2-MWCNTs with in-situ synthesized soluble phenoxazine dye molecules. The none and functionalized TiO2-MWCNTs composites were analyzed by a range of analytical techniques including XRD, Raman, XPS, SEM and UV-vis diffuse reflectance spectroscopy (DRS), and dynamic light scattering (DLS). The photocatalytic activity was evaluated toward the liquid-phase degradation of MB in aqueous solution under both UV and visible light irradiation. TiO2-MWCNTs with optimized mole ratio exhibit much higher photocatalytic activity and stability than bare TiO2. The as-prepared TiO2-MWCNTs photocatalyst possessed good adsorptivity of dyes, extended light absorption range and efficient charge separation properties simultaneously. The results indicated that the soluble phenoxazine dyes and amino-benzenesulfonic acid monomers were covalently grafted on to the surfaces of TiO2-MCNTs, which promoted good aquatic dispersibility and extended light absorption, resulting in increased photocatalytic efficiency., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Injectable hydrogels for bone regeneration consisting of chitosan, sodium beta-glycerophosphate (Na-β-GP) and alkaline phosphatase (ALP) were enriched with the polyphenols phloroglucinol (PG) and gallic acid (GA) and characterized physicochemically and biologically with respect to properties relevant for applications in bone regeneration, namely gelation kinetics, mineralizability, antioxidant properties, antibacterial activity, cytocompatibility and ability to support adhesion and growth of human osteoblast-like MG63 cells. Enrichment with PG and GA had no negative effect on gelation kinetics and mineralizability. PG and GA both enhanced antioxidant activity of unmineralized hydrogels. Mineralization reduced antioxidant activity of hydrogels containing GA. Hydrogels containing GA, PG and without polyphenols reduced colony forming ability of Escherichia coli after 1h, 3h and 6h incubation and slowed E. coli growth in liquid culture for 150min. Hydrogels containing GA were cytotoxic and supported cell growth more poorly than polyphenol-free hydrogels. PG had no negative effect on cell adhesion and growth., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The potential of nanoscaled cellulose and enzymatically phosphorylated derivatives as bio-adsorbents to remove metal ions (Ag(+), Cu(2+) and Fe(3+)) from model water and industrial effluents is demonstrated. Introduction of phosphate groups onto nanocelluloses significantly improved the metal sorption velocity and sorption capacity. The removal efficiency was considered to be driven by the high surface area of these nanomaterials as well as the nature and density of functional groups on the nanocellulose surface. Generally, in the solutions containing only single types of metal ions, the metal ion selectivity was in the order Ag(+)>Cu(2+)>Fe(3+), while in the case of mixtures of ions, the order changed to Ag(+)>Fe(3+)>Cu(2+), irrespective of the surface functionality of the nanocellulose. In the case of industrial effluent from the mirror making industry, 99% removal of Cu(2+) and Fe(3+) by phosphorylated nanocellulose was observed. The study showed that phosphorylated nanocelluloses are highly efficient biomaterials for scavenging multiple metal ions, simultaneously, from industrial effluents., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Nano-sized cellulose ester derivatives having phosphoryl side groups were synthesised by phosphorylation of nanofibrilated cellulose (NFC) and nanocrystaline cellulose (NCC), using different heterogeneous (in water) and homogeneous (in molten urea) processes with phosphoric acid as phosphoryl donor. The phosphorylation mechanism, efficacy, stability, as well as its influence on the NC crystallinity and thermal properties, were evaluated using ATR-FTIR and (13)C NMR spectroscopies, potentiometric titration, capillary electrophoresis, X-ray diffraction, colorimetry, thermogravimmetry and SEM. Phosphorylation under both processes created dibasic phosphate and monobasic tautomeric phosphite groups at C6 and C3 positioned hydroxyls of cellulose, yielded 60-fold (∼1,173 mmol/kg) and 2-fold (∼1.038 mmol/kg) higher surface charge density for p-NFC and p-NCC, respectively, under homogenous conditions. None of the phosphorylations affected neither the NC crystallinity degree nor the structure, and noticeably preventing the derivatives from weight loss during the pyrolysis process. The p-NC showed high hydrolytic stability to water at all pH mediums. Reusing of the treatment bath was examined after the heterogeneous process., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The acetylation efficiency of nanofibrillated cellulose (NFC) with acetic anhydride as acetyl donor was studied using lipase from Aspergillus niger in a mixture of dimethyl sulphoxide (DMSO) and phosphate buffer solution at ambient conditions and in supercritical carbon dioxide (scCO2). The chemical acetylation of NFC with comparable ester content was carried out for comparison. The ATR-FTIR, solid-state CP/MAS (13)C NMR and DSC analyses revealed that, besides the enzyme-catalysed acetylation, predominantly appearing at the C-6 position of cellulose hydroxyls, a strong and stable acyl-enzyme intermediate attachment also occurred on the NFC via Maillard reaction. Enzymatic acetylation via attached acyl-enzyme complex on NFC yielded high hydophobicity (contact angle of 84±9°), whereas the chemical acetylation with comparable ester content resulted in a much lower hydrophobic surface with a contact angle of 33±3°. Finally, the adsorption capacity profiles of lysozyme and BSA proteins on native, chemically and enzymatically acetylated NFC as a function of the pH medium were determined., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The adsorption of chemically similar but differently oxygen reactive phenolic-acid derivatives on the Ti-nanotubes (TiNTs) surfaces to increase and/or broaden their photo-induced activity was studied using Raman and X-ray photoelectron spectroscopies combined with zeta-potential analyses. Photo-catalytic activities and stabilities of newly synthesized particles were evaluated by using high-resolution capillary electrophoresis in combination with cyclic voltammetry and spin-trapping EPR spectroscopy. The modification with caffeic acid (CA) resulted in well-oriented and dense but oxygen semi-stable thin layer (1-3 nm) of self-assembled mono-molecular and/or bi-dentate coordinated molecules on the TiNTs' surfaces, which narrowed the band gap from 2.9 eV (for un-modified TiNTs) to 1.55 eV, but however restrict the hydroxyl radicals generation under both UV (320 nm) and VIS (450 nm) source radiations. On the other hand, the gallic acid (GA) resulted in situ polymerized GA layer through bi-dentate binding as highly-oxygen-stabilized surface structure, yielding narrower band gap of 2.25 eV and increased hydroxyl radical's generation under both exposure lights. The third tested hydroxybenzoic acid (HA), resulted to an unstable layer bonded thorough single-hydrogen bonding mechanism. This work offers a new modification strategy for stable (oxygen and photo-induction related) and highly visible-light responded TiNTs as photocatalyst., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: The purpose of this study was to test a new method of dental panoramic tomogram (DPT) analysis to show the differences of mandibular bone volume and relative bone density (RBD) in order to detect osteoporosis., Materials and Methods: A case-control study compared 62 women with osteoporosis (O) and 24 women with osteopenia (o) to a control group of 33 women with normal bone mineral density (N). DPTs were analyzed using an original method resulting in anatomic and RBD indexes as well as using previously described methods: panoramic mandibular index (PMI) and mandibular cortical width (MCW)., Results: One anatomic and four RBD indexes differed statistically significantly between the group O and N and three RBD indexes differed statistically significantly between o and N. PMI did not show statistically significant differences between the groups. The MCW differed significantly at two measured sites between O and N., Conclusions: Average values of RBD indexes were statistically significantly different between O and N and also between o and N. Important differences regarding RBD were confirmed using a new and original method of common DPT analysis. This method could serve as a screening tool for osteoporosis., (Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Homogeneous and heterogeneous methods for functionalization of chitosan with quercetin or tannic acid using laccase from Trametes versicolor is presented, yielding a bio-based product with synergistic antioxidant and antimicrobial properties. HPLC-SEC analysis and cyclic voltammetry kinetic studies showed that laccase catalyzes the oxidation of quercetin to electrophilic o-quinones, which undergo to an oligomer/polymer-forming structures. On the other hand, tannic acid was converted into gallic acid, its dimers, partially gallic acid esterified glucose and glucose, when exposed to laccases. ATR-FTIR spectroscopy provided evidence that quercetin o-quinones undergo coupling reactions with amino groups of chitosan via Schiff-base and Michael addition mechanisms under heterogeneous method, while oxidized tannic acid cross-linked with chitosan by hydrogen and electrostatic interactions under both methods. All polyphenols functionalized chitosans showed greatly improved ABTS(+) cation radicals scavenging capacity, compared with the untreated chitosan, while antimicrobial activities significantly depended on the mode of functionalization and type of microorganism., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Introduction: The aim of this study was to evaluate 3-dimensional facial shells by incorporating a population-specific average template with a group of Class III subjects preparing to have orthognathic surgery., Methods: The Class III group included 14 male (MCIII) and 15 female (FCIII) subjects. We used 43 male and 44 female Class I subjects to construct average male (AvM) and female (AvF) faces. Coordinates of 3 points on the facial templates of groups MCIII and FCIII and the templates AvM and AvF were compared. MCIII-AvM and FCIII-AvF superimpositions were evaluated for differences., Results: Vertical distances (sella to soft-tissue pogonion) were statistically significantly higher for the AvM (9.1%) and MCIII (10.1%) than for the AvF and FCIII, respectively (P < 0.05). The distances of soft-tissue pogonion in the horizontal x-axis were positive in 80% of the FCIII group and 85.7% of the MCIII group. The Class III subjects differed from the average face in the lower two thirds, but, in 50% (MCIII) and 60% (FCIII), they differed also in the upper facial third., Conclusions: (1) The average and Class III Slovenian male morphologic face heights are statistically significantly higher than those of the female subjects. (2) The Slovenian Class III male and female subjects tend toward a left-sided chin deviation. (3) Differences between Class III patients and a normative data set were determined., (Copyright © 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)