[Show abstract][Hide abstract] ABSTRACT: Immune system is believed to play an important role in cancer initiation as well as its progression, as evidenced by many studies revealing suppressed, defective anti-tumor immunity in cancer patients. Modulating various components in immune surveillance, such as cytokine, antigen-presenting cells, or B/T lymphocytes, to control and eradicate cancer has been an attractive theme, however, preclinical/clinical trials have not been successful enough to introduce immunotherapy into practice. Recently, enthusiasm on cancer immunotherapy has been revived mostly due to 1) growing body of data on the mechanism of immune checkpoint in cancer, and 2) promising studies performed in advanced, solid cancer patients treated with blocking antibodies targeting cytotoxic T lymphocyte-associated antigen-4 or programmed cell death protein-1 pathways. The immune checkpoints blockade is likely to be a novel armament in cancer management as the outcomes of ongoing clinical trials are released in future.
[Show abstract][Hide abstract] ABSTRACT: A series of bipolar anthracene derivatives containing pyridine as an electron withdrawing group and cabazole, triphenylamine and indole as electron donating groups were synthesized and characterized. Particularly, Device E, 9-(4′-(10-(pyridin-2-yl)anthracen-9-yl)biphenyl-4-yl)-9H-carbazol
exhibits a high-efficient deep-blue EL emission with the luminous efficiency (LE) of 2.31 cd/A, power efficiency (PE) of 1.39 lm/W and quantum efficiency (QE) of 1.94% at 500 nit. This compound shows the maximum wavelength of the electroluminescence (EL) at 467 nm and the CIE x, y
coordinates of (0.16, 0.14) at 6 V.
No preview · Article · Aug 2014 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: A series of bipolar anthracene derivatives containing triphenylamine as an electron donating group and pyridine, quinoline, isoquinoline and benzothiazole as electron withdrawing groups were synthesized and characterized. Particularly, a material, 9-quinolinyl-10-triphenylamin anthracene (3) exhibits a highly efficient sky-blue EL emission with the luminous efficiency (LE) of 9.36 cd/A, power efficiency (PE) of 5.94 lm/W and quantum efficiency (QE) of 4.23% at 500 nit. This material shows the maximum wavelength of the electroluminescence (EL) at 486 nm and the CIE x, y coordinates of (0.17, 0.36) at 6 V.
No preview · Article · Aug 2014 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: We report an improvement of efficiency in red phosphorescent organic light-emitting diodes (PHOLEDs) based on a combination of heterojunction (HJ) structure and mixed host (MH) system using a phosphorescent red emitter: bis(2-phenylquinolinato)-acetylacetonate iridium III [Ir(pq)2(acac)]
doped in 4,4,N,N′-dicarbazolebiphenyl (CBP) of hole transport type host material and 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi) of electron transport type host material. This combination device resulted in an effective electron and hole balance and distribution
of the recombination zone. Therefore, highly efficient red PHOLEDs with maximum luminous efficiency and external quantum efficiency of 21.93 cd/A and 14.09% were achieved. Moreover, the combination device showed a power efficiency of 9.51 lm/W, which is higher than 7.61 lm/W in the control
device at a luminance of 1000 cd/m2.
No preview · Article · Aug 2014 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: Although several studies reported that distant metastasis occurs more frequently in the tumors of submandibular gland (SMG) than parotid gland (PG), why SMG tumors preferentially metastasize to distant organs is not fully understood. We aimed to identify the differential tumor microenvironment for distant metastasis and possible underlying mechanisms.
We retrieved 27 cases of 1-4-cm-sized adenoid cystic carcinomas (ACCs) arising from the PG (n = 12) and SMG (n = 15). c-KIT, VEGF-R2, and CD31 staining were quantified by image-based analysis to define the positive expression or tumor-associated vessel areas in two representative sections per case. In addition, angiogenesis-related genomic expression profiling was carried out to explore the underlying mechanism, which was confirmed by RT-PCR and immunohistochemistry.
Earlier systemic dissemination within 2 years was detected exclusively in SMG ACCs (5/15). The area of tumor-associated blood vessels was larger in SMG ACCs than PG ACCs, and ACCs showing distant metastasis had greater blood vessel area than those without metastasis. Interestingly, normal SMG had more blood vessels per area than PG. Among angiogenesis-related signals, the level of IL-6 was significantly lower in SMG ACCs than PG ACCs. Moreover, IL-6 expression decreased significantly in SMG ACCs compared with that in normal SMG, whereas it was up-regulated in PG ACCs.
ACCs in the SMG microenvironment have more abundant tumor-associated blood vessels than PG ACCs, which may explain the higher risk of distant metastasis from SMG tumors.
No preview · Article · Jan 2014 · Journal of Oral Pathology and Medicine
[Show abstract][Hide abstract] ABSTRACT: Auditory neuropathy is a hearing disorder characterized by the absence or the marked impairment of the auditory brainstem responses with the preservation of the cochlear microphonics (CMs) and otoacoustic emissions. This suggests that outer hair cell (OHC) function is normal but proximal auditory function to OHCs is impaired. It is assumed that the lesion is localized at the level of the inner hair cells (IHCs), auditory nerve fibers, or the synapse between them. This study was aimed to observe the change of hearing threshold and pathology of spiral ganglion cell induced by ouabain application, and present basic data to explain the auditory neuropathy.
[Show abstract][Hide abstract] ABSTRACT: A series of blue fluorescent materials 1–3 based on 10-(2-napthyl)-anthracene derivatives with the diverse aromatic groups were synthesized and multilayer non-doped devices using them as emitting materials were fabricated. All OLED devices using these materials emit deep blue light of 446–456 nm. In particular, device 3 exhibited highly efficient blue emissions with the luminous efficiency of 3.89 cd/A, a power efficiency of 2.47 lm/W, Quantum Efficiency of 3.03% at 20 mA/cm2, and CIEx,y coordinates of (0.163, 0.149) at 6 V. Also, device 2 showed the efficient deep-blue emission with CIE coordinates of (x = 0.151, y = 0.104) at 6 V.
No preview · Article · Dec 2013 · Molecular Crystals and Liquid Crystals
[Show abstract][Hide abstract] ABSTRACT: A main requirement for achieving high efficiency in organic light-emitting diodes (OLEDs) is that all charges and electrically generated excitons should be employed for emission. We fabricated blue phosphorescent OLEDs with four types electron transporting layers, which were doped with lithium quinolate (Liq) from 0% to 10%. A series of blue devices consisted of indium tin oxide (ITO, 180 nm)/4,4-bis[N-(naphthyl)-N-phenyl-amino]biphenyl (NPB, 50 nm)/N,N′-dicarbazolyl-3,5-benzene (mCP, 10 nm)/iridium(III)bis[(4,6-di-fluoropheny)-pyridinato-N,C2] picolinate (FIrpic) doped in mCP (8%, 30 nm)/1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi, 20 nm)/TPBi mixed with Liq (20 nm)/Liq (2 nm)/aluminum (Al, 100 nm). The blue OLED doped with 5% Liq, which demonstrated a maximum luminous efficiency and external quantum efficiency of 17.64 cd/A and 8.78%, respectively, were found to be superior to the other blue devices.
[Show abstract][Hide abstract] ABSTRACT: Systematic studies on carrier injection and transport are very important for achieving high efficiency in OLEDs. We demonstrate excellent green phosphorescent organic light-emitting diodes (OLED) with lithium quinolate (Liq) doped in 1,3,5-tris(N-phenylbenzimidazole-2-yl) benzene (TPBi) as the electron transport layer (ETL). The doping concentration of Liq was varied from 0% to 10%. The optimized green phosphorescent OLED with 5% Liq in the ETL showed the best efficiencies, which were maximum luminous efficiency, power efficiency, and quantum efficiency of 65.76 cd/A, 57.39 Im/W, and 20.03%, respectively. Moreover, high triplet energy states of TCTA and TPBi as a triplet exciton-blocking layer (TEBL) played a role in efficient exciton confinement.
No preview · Article · Dec 2013 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: The authors have demonstrated a highly efficient and stable phosphorescent white organic light-emitting diode (WOLED), which has been achieved by doping only one orange phosphorescent emitter, Bis(5-benzoyl-2-(4-fluorophenyl)pyridinato-C,N)iridium(III) acetylacetonate into an appropriate deep blue phosphorescent host, 4,4'-bis(4-(triphenylsilyl)phenyl)-1,1'-binaphthyl as an emitting layer (EML). The WOLED has been achieved by effective confinement of triplet excitons to emit a warm white color. The optimized WOLED, with a simple structure as a hole transporting layer-EML-electron transporting layer, showed a maximum luminous efficiency of 22.38 cd/A, a maximum power efficiency of 12.01 lm/W, a maximum external quantum efficiency of 7.32%, and CIEx,y coordinates of (0.38,0.42) at 500 cd/m2, respectively.
No preview · Article · Oct 2013 · Thin Solid Films
[Show abstract][Hide abstract] ABSTRACT: Derlin-1 plays a critical role in endoplasmic reticulum-associated protein degradation (ERAD) of a particular subset of proteins. Although it is generally accepted that Derlin-1 mediates the export of ERAD substrates from the ER to the cytosol, little is known about how Derlin-1 interacts with these substrates. Human cytomegalovirus (HCMV) US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules and evade immune surveillance. US11 requires the cytosolic tail of the MHC-I heavy chain to divert MHC-I molecules into the ERAD pathway for degradation; however, the underlying mechanisms remain unknown. Here, we show that the cytosolic tail of the MHC-I heavy chain, although not required for interaction with US11, is required for tight binding to Derlin-1 and thus for US11-induced dislocation of the MHC-I heavy chain to the cytosol for proteasomal degradation. Surprisingly, deletion of a single C-terminal amino acid from the cytosolic tail disrupted the interaction between MHC-I molecules and Derlin-1, rendering mutant MHC-I molecules resistant to US11-induced degradation. Consistently, deleting the C-terminal cytosolic region of Derlin-1 prevented it from binding to MHC-I molecules. Taken together, these results suggest that the cytosolic region of Derlin-1 is involved in ERAD substrate binding and that this interaction is critical for the Derlin-1-mediated dislocation of the MHC-I heavy chain to the cytosol during US11-induced MHC-I degradation.
[Show abstract][Hide abstract] ABSTRACT: CNTs-Al matrix composites are considered to be promising heat dissipating materials because thermal conductivity can potentially be improved whilst their density is reduced. Although casting has many advantages in the fabrication of large, complex components, this process cannot be easily employed when manufacturing CNTs-Al composites. In order to produce CNTs-Al matrix composites by casting a CNTs-Al powder precursor was manufactured using mechanical milling and electroless plating processes. Aluminium powder with CNTs of 10 wt.% and 20 wt.% were mixed and ball milled using a horizontal mill. After milling for 3 hrs., the milled powder exhibits a flattened morphology with a band-type distribution of CNT clusters observed within the aluminium particles. Prolonged milling of up to 24 hrs. introduces an equiaxed particle shape for the milled powders with a uniform distribution of CNTs within the aluminium particles. However, as milling time increases, the CNTs become fractured by ball-to-ball collisions. There was no reaction evident between the aluminium and the CNTs at milling times up to 24 hrs. In order to improve the wettability between the CNTs-Al powder precursor and Al melt during the casting process, electroless Ni plating was performed. The processing time for the Ni-plating affects the uniformity of the coating layer. For a uniform coating condition, the average thickness of the coating was ~1.87 μm, with no evidence of gaps between the milled powders and coatings observed.
No preview · Article · Jul 2013 · Materials Science Forum
[Show abstract][Hide abstract] ABSTRACT: According to a recent report, the organic light-emitting diodes (OLEDs) using the iridium complexes of coumarin derivatives as emissive dopants are highly efficient and stable. Unlike the other Ir(III) phopsphorescent dopants, these coumarin-based Ir(III) complexes can effectively trap and transport electrons in the emissive layer. We have prepared a series of phosphorescent cyclometalated Ir(III) complexes containing 3-(2-pyridinyl)coumarin (pc) as an ancillary ligand. The new heteroleptic iridium complexes, Ir(C--N)2(pc) (CAN = 2-(2,4-difluorophenyl)pyridine (F2-ppy), 2-phenylpyridine (ppy) and 2-phenylquinoline (pq)) were characterized by 1H NMR and mass spectrometer. As main ligands, F2-ppy, ppy and pq were employed, which should have the drastically different ligand molecular orbital energy levels. The iridium complexes showed various emission ranges from 560 to 610 nm, depending upon the relative energy levels of their main and ancillary ligands. The photoabsorption, photoluminescence and electroluminescence of the complexes were studied. We also investigated the electrochemical properties of the iridium complexes to compare the HOMO and LUMO energy levels of these phosphorescent materials.
No preview · Article · May 2013 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: We have demonstrated a stable phosphorescent white organic light-emitting diodes (WOLEDs) using an orange emitter, Bis(5-benzoyl-2-(4-fluorophenyl)pyridinato-C,N) iridium(III)acetylacetonate [(Bz4Fppy)2Ir(III)acac] doped into a newly synthesized blue host material, 2-(carbazol-9-yl)-7-(isoquinolin-1-yl)-9,9-diethylfluorene (CzFliq). When 1 wt.% (Bz4Fppy)2Ir(III)acac was doped into emitting layer, it was realized an improved EL performance and a pure white color in the OLED. The optimum WOLED showed maximum values as a luminous efficiency of 10.14 cd/A, a power efficiency of 10.24 Im/W, a peak external quantum efficiency 4.07%, and Commission Internationale de L'Eclairage coordinates of (0.34, 0.39) at 8 V.
No preview · Article · Mar 2013 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: Background:
Preoperative differentiation between high-grade malignancy and others (benign or low-grade tumors) is more important than differentiation between malignant and benign tumors for surgical planning, treatment outcome, and prognosis in salivary gland tumors. Fine needle aspiration cytology (FNAC) has a relatively low sensitivity for differentiating malignant from benign salivary tumors. However, the diagnostic performance of FNAC has not been studied in predicting high-grade salivary malignancy, which can significantly affect patient care.
Experienced cytopathologists reevaluated the adequate FNAC on 521 salivary gland tumors. The diagnostic performances of FNAC for total malignancy and high-grade malignancy were calculated, and the results were validated in independent 105 cases. In cases of high-grade cancer on FNAC, we recorded the additional diagnostic procedures and the change of surgical extent to decide how FNAC impacts clinical practice.
The sensitivity, specificity, and diagnostic accuracy of FNAC in differentiating malignant from benign tumors were 64.2 % (95 % confidence interval 52.3-75.0), 98.4 % (96.5-99.3), and 92.1 % (89.1-94.6). Meanwhile, FNAC predicted high-grade malignancy accurately (94.6 % [80.0-99.5], 99.2 % [97.8-99.7], 98.9 % [97.3-99.6], respectively), a finding reproduced with similar results in the validation set. FNAC indicative of high-grade malignancy added additional imaging assessments in 94.9 %, frozen biopsy samples during surgery (tumor and lymph nodes) in 71.2 %, and changed the extent of surgery in 59.0 %.
FNAC has an excellent diagnostic performance in discriminating high-grade salivary cancer, which guides clinical decision and surgical planning in salivary gland tumors.
No preview · Article · Feb 2013 · Annals of Surgical Oncology
[Show abstract][Hide abstract] ABSTRACT: Pinworm infection can occur through contact with contaminated surfaces followed by ingestion or even through inhalation of infective eggs. We have limited information regarding environmental contamination by eggs of . In order to determine environmental risk factors associated with the rate of infection, we investigated possible environmental risk factors using a questionnaire from 46 kindergartens in 3 different cities of the southeast area of Korea. In total, using the cellotape anal swab technique, 3,422 children were examined for infection. We evaluated egg of books, educational materials, toys, room door handles, dusts of window edges, desks, chairs, tables, and dusts of classrooms. The overall egg-positive rate for was 6.0%, and the prevalence of enterobiasis in each kindergarten ranged between 0% and 16.9%. We found that 78.9% of egg positive kindergartens were managed by private foundations, which was significantly higher, compared with kindergartens managed by public foundations or the nation. Compared with public or national kindergartens, most private kindergartens were located in residential areas and the number of children in these areas was significantly higher. In conclusion, numbers of children in kindergartens was found to be an environmental risk factor associated with transmission of enterobiasis in Korea.
Full-text · Article · Feb 2013 · The Korean Journal of Parasitology
[Show abstract][Hide abstract] ABSTRACT: The Vibrant Soundbridge (VSB) middle ear implant is an alternative rehabilitation option for sensorineural, conductive, and mixed hearing loss. The mechanism of VSB implantation is direct-drive stimulation of the inner ear through a floating mass transducer placed on the ossicular chain. We report our experience of VSB incus vibroplasty, which were successfully performed in two cases without complications and resulted in good functional gain and improve-ment of speech discrimination.
[Show abstract][Hide abstract] ABSTRACT: Carotenoids produced by non-photosynthetic bacteria protect organisms against lethal photodynamic reactions and scavenge oxygenic radicals. However, the carotenoid produced by Gordonia alkanivorans SKF120101 is coupled to reducing power generation. SKF120101 selectively produces carotenoid under light conditions. The growth yield of SKF120101 cultivated under light conditions was higher than that under dark condition. In the cyclic voltammetry, both upper and lower voltammograms for neutral red (NR) immobilized in intact cells of SKF120101 were not shifted in the condition without external redox sources but were commonly shifted downward by glucose addition and light. Electric current generation in a biofuel cell system (BFCS) catalyzed by harvested cells of SKF120101 was higher under light than dark condition. The ratio of electricity generation to glucose consumption by SKF120101 cultivated in BFCS was higher under light than dark condition. The carotenoid produced by SKF120101 catalyzes production of reducing power from light energy, first evaluated by the electrochemical technique used in this research.
No preview · Article · Nov 2012 · Journal of Microbiology and Biotechnology
[Show abstract][Hide abstract] ABSTRACT: Conclusion:
The results revealed that children with intellectual disability (ID) who underwent cochlear implantation (CI) showed gradual progress in their auditory perception and speech development. ID in children should not be considered a contraindication for CI, because they are able to obtain a chance to develop oral communication skills following CI.
The purpose of this study was to assess the auditory and speech performance of 14 young deaf children with ID after CI.
Fourteen children with ID who underwent CI between December 2002 and February 2010 were included. Improvement in auditory perception and speech production over time was evaluated longitudinally with the Categories of Auditory Performance (CAP) score and Korean version of Ling's stages (K-Ling). The results were compared with those of age- and gender-matched implanted controls without additional disabilities. All tests were performed four times in each patient: before implantation and at 3, 6, and 12 months after implantation. Preoperative and postoperative communication modes were also assessed and compared between the two groups.
Auditory perception and speech production of deaf children with an ID improved consistently after CI. In addition, the communication mode also took a favorable turn from nonverbal to vocalizations or oral communication or from vocalizations to oral communication.
No preview · Article · Oct 2012 · Acta oto-laryngologica
[Show abstract][Hide abstract] ABSTRACT: The new heteroleptic iridium complexes bearing 2-(5-phenyl-1,3,4-oxadiazol-2-yl)phenolate (ODZ), were synthesized and characterized for application to organic light-emitting diodes (OLEDs). As main ligands (C^N), the anions of 2-phenylpyridine (ppy), 2-phenylquinoline (pq) and 2-(2,4-difluorophenyl)pyridine (F2-ppy) were chelated to the iridium center and 2-(5-phenyl-1,3,4-oxadiazol-2-yl)phenolate (ODZ) was introduced as an ancillary ligand for luminescence modulation of their iridium complexes. We expected that the relative energy levels of the main and ancillary ligands in the complexes could lead to emission color tuning and luminous efficiency improvement by possible inter-ligand energy transfer (ILET). The photoabsorption, photoluminescence and electroluminescence of the complexes were studied. Ir(F2-ppy)2(ODZ), Ir(ppy)2(ODZ) and Ir(pq)2(ODZ) exhibited the photoluminescence maxima between 505-610 nm at room temperature in CH2Cl2, depending on both main and ancillary ligands. The longer pi conjugation in the cyclometallating pq ligands leads to the bathochromic shift in luminescence of their iridium complexes. The electroluminescent properties of the complexes were influenced by ILET.
No preview · Article · Jul 2012 · Journal of Nanoscience and Nanotechnology