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Background and Objectives Fungal biofilm is commonly found in non-invasive fungal rhinosinusitis. Previous endodontic maxillary teeth treatments have increased fungus ball development in the maxillary sinus. We sought to evaluate the effects of zinc oxide (ZnO), the main component of endodontic sealers, on developing the Aspergillus fumigatus biofilms on primary human nasal epithelial cells.Subjects and Method Primary human nasal epithelial cells were cultured with A. fumigatus spores with (1 and 3 µg/mL) or without ZnO for 72 h. Interleukin (IL)-6, IL-8, and transforming growth factor (TGF)-β1 levels in cultural supernatant were determined by enzyme linked immunosorbent assay. ZnO’s effects on the formation of A. fumigatus biofilm were determined using crystal violet, safranin, concanavalin A staining, and confocal scanning laser microscopy.Results IL-6, IL-8, and TGF-β1 protein levels in primary human nasal epithelial cells increased significantly by A. fumigatus exposure. During coculturing with ZnO and A. fumigatus, biofilm dry weight, crystal violet, safranin, and concanavalin A staining intensity increased with time. On the other hand, ZnO did not enhance A. fumigatus biofilm formation.Conclusion A. fumigatus biofilm formation increased in the presence of primary human nasal epithelial cells. However, in vitro study, ZnO alone did not influence or aggravate biofilm formation in sinonasal mucosa.

Parathyroid carcinoma is very rare malignant neoplasm, accounting for less than 0.005% of all cancers. Most parathyroid carcinoma is a functioning tumor that causes hyperparathyroidism, leading to hypercalcemia. We report a parathyroid carcinoma case that was suspicious for spontaneous infarction of cancer, leading to resolution of hypercalcemia. A 29-year-old male visited our hospital presenting with right neck swelling and pain. He has been experiencing frequent urolithiasis for four years but laboratory tests showed normal serum calcium level. Right vocal cord paresis was identified with laryngoscopy. Ultrasonography revealed a 3.7 × 3.5 cm mass in the right thyroid containing a focal cystic portion. Computed tomography confirmed the presence of a low-density right thyroid mass. Right thyroid lobectomy was performed and pathological evaluation revealed parathyroid carcinoma with central necrosis. We report this very rare case with a literature review.

Flammability was evaluated and the results showed the values of critical flux at extinguishment (CFE) as 49.5kW/㎡ on average, total heat release (Qt) as 0.21MJ on average, and peak heat release rate (Qp) as 0.66kW on average, which satisfied all of the thresholds presented by the IMO. Therefore, flame-retardant plywood, of which the flame-retardant performance was evaluated, was determined to be an applicable finishing material that satisfies fire safety standards.

The objective of this study is to achieve a fundamental understanding of polymorphic interconversion during the tableting process, including during compaction, dwell, decompression/unloading, and ejection using an in situ mechanical Raman spectroscopy. The fit-for-purpose in situ mechanical Raman spectroscopy developed herein can provide simultaneous measurement of Raman spectra and densification for the powder compacts. Chlorpropamide (CPA), an antidiabetic drug, was selected as a model pharmaceutical compound because of its mechanical shear-induced polymorphic conversions. The results confirm that CPA polymorph A (CPA-A) was transformed to CPA polymorph C (CPA-C) under different compaction stresses. We also observed that the converted polymorph CPA-C could be reverted to the CPA-A due to the elastic recovery of powder compacts as detected during dwelling and unloading. This study is the first depiction of the dynamics of CPA polymorphic interconversion during compression, dwell, unloading, and ejection. Mechanistically, this study illustrates a correlation between the change in the powder compact's relative density and polymorphic interconversion of the drug substance in different solid-state forms. The present research suggests that the process-induced polymorph conversion is a complicated dynamic process, which could be affected by the compaction pressure, the elasticity/plasticity of the material, the level of elastic recovery, and the dissipation of residual stress. In summary, this study demonstrates that the in situ mechanical Raman spectroscopy approach enables the simultaneous detection of mechanical and chemical information of the powder compact throughout the tableting process.

Wood-based materials are multifunctional green and environmentally friendly natural construction materials, and are widely used in decorative building materials. For this reason, a lot of research has been carried out to develop new and innovative wood surface improvements and make wood more appealing through features such as fire-retardancy, hydrophobicity, and antibacterial properties. To improve the performance of wood, more and more attention is being paid to the functioning of the surface. Understanding and mastering technology to improve the surface functionality of wood opens up new possibilities for developing multifunctional and high-performance materials. Examples of these techniques are ion crosslinking modification and coating modification. Researchers have been trying to make wooden surfaces more practical for the past century. This study has gradually gained popularity in the field of wood material science over the last 10 years. This paper provides an experimental reference for research on wood surface functionalization and summarizes the most current advancements in hydrophobic, antibacterial, and flame-retardant research on wood surfaces.

In this study, supercritical fluid-assisted spray-drying (SA-SD) was applied to achieve the micronization of fenofibrate particles possessing surface-active additives, such as d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), sucrose mono palmitate (Sucroester 15), and polyoxyethylene 52 stearate (Myrj 52), to improve the pharmacokinetic and pharmacodynamic properties of fenofibrate. For comparison, the same formulation was prepared using a spray-drying (SD) process, and then both methods were compared. The SA-SD process resulted in a significantly smaller mean particle size (approximately 2 μm) compared to that of unprocessed fenofibrate (approximately 20 μm) and SD-processed particles (approximately 40 μm). There was no significant difference in the effect on the particle size reduction among the selected surface-active additives. The microcomposite particles prepared with surface-active additives using SA-SD exhibited remarkable enhancement in their dissolution rate due to the synergistic effect of comparably moderate wettability improvement and significant particle size reduction. In contrast, the SD samples with the surface-active additives exhibited a decrease in dissolution rate compared to that of the unprocessed fenofibrate due to the absence of particle size reduction, although wettability was greatly improved. The results of zeta potential and XPS analyses indicated that the surface-active additive coverage on the surface layer of the SD-processed particles with a better wettability was higher than that of the SA-SD-processed composite particles. Additionally, after rapid depletion of hydrophilic additives that were excessively distributed on the surfaces of SD-processed particles, the creation of a surface layer rich in poorly water-soluble fenofibrate resulted in a decrease in the dissolution rate. In contrast, the surface-active molecules were dispersed homogeneously throughout the particle matrix in the SA-SD-processed microparticles. Furthermore, improved pharmacokinetic and pharmacodynamic characteristics were observed for the SA-SD-processed fenofibrate microparticles compared to those for the SD-processed fenofibrate particles. Therefore, the SA-SD process incorporating surface-active additives can efficiently micronize poorly water-soluble drugs and optimize their physicochemical and biopharmaceutical characteristics.

Fibrous dysplasia (FD) is a rare benign disease that replaces a normal bone with abnormal fibrous and weak osseous tissue. It is usually detected in childhood and rarely occurs in old age. Although the disease is known to be caused by a genetic mutation, only a single case of FD secondary to surgery is reported in the literature. We report a case of monostotic FD of the maxillary sinus in a 70-year-old Asian woman who presented with incidental calcific lesion in the maxillary sinus on a brain computed tomography scan. At 32 months prior to presentation, the patient had undergone an endoscopic sinus surgery for a fungal ball of the same sinus. The lesion was removed by endoscopic surgery, and the histopathological evidence was consistent with FD. To the best of our knowledge, this is the second case of a postsurgical craniofacial FD, and a rare case that occurred in old age.

A novel design for thermally activated delayed fluorescence (TADF) emitters was developed by decorating dibenzofuran with four carbazole type electron donors and two CN electron withdrawing units. The four carbazole type donors were attached to one side of the dibenzofuran, and two CN units were introduced on the other side of the dibenzofuran for highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) separation. The HOMO and LUMO were largely separated, and they were overlapped in the dibenzofuran due to aromatic nature of dibenzofuran. Two TADF emitters, DBFCzCN and DBFtCzCN, were built on the design platform decorating the dibenzofuran, and they showed high EQEs of 25.2% and 17.4% in the vacuum deposited TADF devices. Additionally, the DBFtCzCN emitter showed a high EQE of 13.9% in the solution processed TADF devices.

A newly designed ruthenium(II) complex (Ru-Se) bearing a selone moiety showed unexpected enhancement in low-oxidation-potential (LOP) electrochemiluminescence (ECL) observed at electrode potentials before the oxidation of Ru-Se in the presence of tri-n-propylamine (TPrA), which was primarily attributed to the heavy atom effect caused by the selone in Ru-Se.

PURPOSE: This study aims to understand the impact of spray drying nozzles on particle surface composition and aerosol stability. METHODS: The combination formulations of colistin and azithromycin were formulated by 2-fluid nozzle (2N) or 3-fluid (3N) spray drying in a molar ratio of 1:1. A 3-factor, 2-level (2(3)) factorial design was selected to investigate effects of flow rate, inlet temperature and feed concentration on yield of spray drying and the performance of the spray dried formulations for the 3N. RESULTS: FPF values for the 2N formulation (72.9 ± 1.9% for azithromycin & 73.4 ± 0.8% for colistin) were higher than those for the 3N formulation (56.5 ± 3.8% for azithromycin & 55.1 ± 1.6% for colistin) when stored at 20% RH for 1 day, which could be attributed to smaller physical size for the 2N. There was no change in FPF for both drugs in the 2N formulation after storage at 75% RH for 90 days; however, there was a slight increase in FPF for colistin in the 3N formulation at the same storage conditions. Surface enrichment of hydrophobic azithromycin was measured by X-ray photoelectron spectroscopy for both 2N and 3N formulations and interactions were studied using FTIR. CONCLUSIONS: The 3-fluid nozzle provides flexibility in choosing different solvents and has the capability to spray dry at higher feed solid concentrations. This study highlights the impact of hydrophobic azithromycin enrichment on particle surface irrespective of the nozzle type, on the prevention of moisture-induced deterioration of FPF for hygroscopic colistin.

배경 및 목적: 국내 대학에 언어재활전공이 처음 개설된 1988년을 기점으로 2018년 현재 총 50개의 대학(대학교, 전문대학, 대학원)에서 총 87개의 프로그램이 운영되고 있다. 이러한 양적 팽창이 이루어진 현 시점에서 각 프로그램들의 운영 현황을 살펴보고 미래를 준비하는 노력이 필요할 것으로 판단된다. 이에 본 연구에서는 전국 대학에 개설되어 있는...

OBJECTIVE: This study aimed to develop dry powder inhaler (DPI) combination formulations of ciprofloxacin and colistin for use in respiratory infections. Effects of colistin on physical stability and aerosolization of spray-dried ciprofloxacin were examined. METHODS: The combination DPI formulations were produced by co-spray drying colistin and ciprofloxacin in mass ratios of 1:1, 1:3 and 1:9. Colistin and ciprofloxacin were also co-sprayed with L-leucine in the mass ratio of 1:1:1. The physical and aerosolization stability of the selected co-sprayed formulations stored at 20, 55 and 75% relative humidity (RH) were examined. Formulation characterizations were carried out using Powder X-ray diffraction (PXRD) for crystallinity, scanning electron microscopy (SEM) for morphology and particle size distribution, and Dynamic Vapor Sorption (DVS) for moisture sorption. Particle surface analysis was performed using X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Spectrometry (EDX) and Nano-Time-of-flight Secondary Ion Mass Spectrometry (Nano ToF-SIMS). Potential intermolecular interactions were studied using Fourier-transform infrared spectroscopy (FTIR). Aerosol performance was evaluated using a multi-stage liquid impinger (MSLI) with a RS01 Monodose inhaler device. RESULTS: PXRD diffractograms showed that the co-spray dried colistin-ciprofloxacin formulation in the mass ratio (1:1) was amorphous at 55% RH for up to 60 days; whereas the co-spray dried colistin-ciprofloxacin (1:3) and colistin-ciprofloxacin (1:9) crystallized after storage for 3 days at 55% RH. However, the extent of crystallization for the combination formulations was less as compared to the spray-dried ciprofloxacin alone formulation. Surface morphology of the co-spray dried formulations at different concentrations did not change even after storage at 55% RH for 60 days, unlike the spray-dried ciprofloxacin alone powder which became rougher after 3 days of storage at 55% RH. Surface analysis data indicated surface enrichment of colistin in the co-spray dried formulations. Increasing colistin concentration on the composite particles surfaces improved aerosol performance of ciprofloxacin. FTIR data demonstrated intermolecular interactions between colistin and ciprofloxacin, thereby delaying and/or preventing crystallization of ciprofloxacin when co-spray dried. Co-spray drying ciprofloxacin with colistin in the mass ratio (1:1) completely prevented crystallization of ciprofloxacin at 55% RH for up to 60 days. However, the colistin-ciprofloxacin formulation (1:1) began to fuse when stored at 75% RH due to moisture absorption resulting in compromised aerosol performance. However, the colistin-ciprofloxacin-leucine (1:1:1) formulation demonstrated no particles fusion, enabling a stable aerosol performance at 75% RH for 7 days. CONCLUSIONS: This study demonstrated that incorporation of colistin in the spray-dried formulations can improve physical stability and aerosolization of amorphous ciprofloxacin at 55% RH. At 75% RH for 7 days, further addition of L-leucine in the formulation prevents particle fusion and deterioration in aerosol performance, attributed to enrichment of non-hygroscopic L-leucine on the particle surface.

Three novel green thermally activated delayed fluorescence (TADF) materials, (5,5′-bis(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-2,2′-bipyrimidine (22bpmAc), 10,10′-([2,5′-bipyrimidine]-2′,5-diylbis(4,1-phenylene))bis(9,9-dimethyl-9,10-dihydroacridine) (25bpmAc), and 2,2′-bis(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-5,5′-bipyrimidine (55bpmAc)) based on bipyrimidine cores as the new electron-accepting units and acridine as the electron-donating unit were designed, synthesized, and applied as green emitters in TADF devices. The TADF emitters were designed to have different nitrogen orientations in the bipyrimidine core. Two emitters, 25bpmAc and 55bpmAc, showed higher quantum efficiencies and narrower emission spectra relative to 22bpmAc. The former emitters have restricted geometry by hydrogen-bonding interactions on a central core, whereas the latter emitter does not have hydrogen bonding. The intramolecular hydrogen-bonding interaction suppressed a nonradiative mechanism in the 25bpmAc and 55bpmAc TADF e...

Solution-processed high-efficiency fluorescent organic light-emitting diodes with an external quantum efficiency over 18% were developed by engineering a host material and device structure designed for solution process. A high triplet energy host material designed for the solution process, (oxybis(3-(tert-butyl)-6,1-phenylene))bis(diphenylphosphine oxide) (DPOBBPE), worked efficiently as the host of blue fluorescent devices because of good solubility, high photoluminescence quantum yield, and good film properties. The DPOBBPE host enabled a high external quantum efficiency of 18.8% in the fluorescent organic light-emitting diodes by the solution process. Moreover, 25.8% external quantum efficiency in the soluble blue thermally activated delayed fluorescent devices was also realized. The 25.8% external quantum efficiency of the DPOBBPE delayed fluorescent device and 18.8% external quantum efficiency of the fluorescent device are the highest efficiency values achieved in the solution-processed blue fluorescent organic light-emitting diodes. Moreover, the solution-processed fluorescent device showed an improved blue color coordinate of (0.14, 0.20) compared to (0.17, 0.31) of the delayed fluorescent device.

A high triplet energy material with the ability to suppress intermolecular interactions was synthesized as a host for a blue thermally activated delayed fluorescence (TADF) emitter for blue-shifted emission color and high quantum efficiency in solution-processed TADF organic light-emitting diodes. The host material, (5-(tert-butyl)-2-(4-(tert-butyl)phenoxy)phenyl)diphenylphosphine oxide (POBBPE), was designed to have a phenoxyphenyl core structure for high triplet energy, a diphenylphosphine oxide group for electron transport, and two tert-butyl units to prevent intermolecular interaction. Solution-processed blue TADF devices were developed using the POBBPE host and 2,3,4,5,6-penta(9H-carbazol-9-yl)benzonitrile (5CzCN) as the emitter, and a high quantum efficiency of 23.3% was achieved. In particular, the color coordinates of the solution-processed POBBPE:5CzCN devices were (0.16, 0.23), which were significantly blue-shifted compared to the color coordinates of (0.17, 0.31) from a previous 5CzCN device fabricated using a well-known bis[2-(diphenylphosphino)phenyl]ether oxide host.