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1.
Oncol Lett ; 27(6): 246, 2024 Jun.
Article En | MEDLINE | ID: mdl-38638845

Bronchoscopy is a frequently used initial diagnostic procedure for patients with suspected lung cancer (LC). Cytological examinations of bronchial washing (BW) samples obtained during bronchoscopy often yield inconclusive results regarding LC diagnosis. The present study aimed to identify molecular biomarkers as a non-invasive method for LC diagnosis. Aberrant DNA methylation is used as a useful biomarker for LC. Therefore, microarray-based methylation profiling analyses on 13 patient-matched tumor tissues at stages I-III vs. non-tumor tissues were performed, and a group of highly differentially methylated genes was identified. A subsequent analysis using bisulfite-pyrosequencing with additional tissues and cell lines revealed six methylated genes [ADAM metallopeptidase with thrombospondin type 1 motif 20, forkhead box C2 (mesenchyme forkhead 1), NK2 transcription factor related, locus 5 (Drosophila), oligodendrocyte transcription factor 3, protocadherin γ subfamily A 12 (PCDHGA12) and paired related homeobox 1 (PRRX1)] associated with LC. Next, a highly sensitive and accurate detection method, linear target enrichment-quantitative methylation-specific PCR in a single closed tube, was applied for clinical validation using BW samples from patients with LC (n=68) and individuals with benign diseases (n=33). PCDHGA12 and PRRX1 methylation were identified as the best-performing biomarkers to detect LC. The two-marker combination showed a sensitivity of 82.4% and a specificity of 87.9%, with an area under the curve of 0.891. Notably, the sensitivity for small cell LC was 100%. The two-marker combination had a positive predictive value of 93.3% and a negative predictive value of 70.7%. The sensitivity was higher than that of cytology, which only had a sensitivity of 50%. The methylation status of the two-marker combination showed no association with sex, age or stage, but was associated with tumor location and histology. In conclusion, the present study showed that the regulatory regions of PCDHGA12 and PRRX1 are highly methylated in LC and can be used to detect LC in BW specimens as a diagnostic adjunct to cytology in clinical practice.

2.
J Korean Med Sci ; 39(2): e28, 2024 Jan 15.
Article En | MEDLINE | ID: mdl-38225788

BACKGROUND: When suspicious lesions are observed on computer-tomography (CT), invasive tests are needed to confirm lung cancer. Compared with other procedures, bronchoscopy has fewer complications. However, the sensitivity of peripheral lesion through bronchoscopy including washing cytology is low. A new test with higher sensitivity through bronchoscopy is needed. In our previous study, DNA methylation of PCDHGA12 in bronchial washing cytology has a diagnostic value for lung cancer. In this study, combination of PCDHGA12 and CDO1 methylation obtained through bronchial washing cytology was evaluated as a diagnostic tool for lung cancer. METHODS: A total of 187 patients who had suspicious lesions in CT were enrolled. PCDHGA12 methylation test, CDO1 methylation test, and cytological examination were performed using 3-plex LTE-qMSP test. RESULTS: Sixty-two patients were diagnosed with benign diseases and 125 patients were diagnosed with lung cancer. The sensitivity of PCDHGA12 was 74.4% and the specificity of PCDHGA12 was 91.9% respectively. CDO1 methylation test had a sensitivity of 57.6% and a specificity of 96.8%. The combination of both PCDHGA12 methylation test and CDO1 methylation test showed a sensitivity of 77.6% and a specificity of 90.3%. The sensitivity of lung cancer diagnosis was increased by combining both PCDHGA12 and CDO1 methylation tests. CONCLUSION: Checking DNA methylation of both PCDHGA12 and CDO1 genes using bronchial washing fluid can reduce the invasive procedure to diagnose lung cancer.


Lung Neoplasms , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Lung Neoplasms/pathology , DNA Methylation , Sensitivity and Specificity , Lung/pathology , Bronchoalveolar Lavage , Bronchoscopy/methods
3.
Sci Rep ; 13(1): 22839, 2023 12 21.
Article En | MEDLINE | ID: mdl-38129447

Goblet cells (GCs) in the conjunctiva are specialized epithelial cells secreting mucins for the mucus layer of protective tear film and playing immune tolerance functions for ocular surface health. Because GC loss is observed in various ocular surface diseases, GC examination is important for precision diagnosis. Moxifloxacin-based fluorescence microscopy (MBFM) was recently developed for non-invasive high-contrast GC visualization. MBFM showed promise for GC examination by high-speed large-area imaging and a robust analysis method is needed to provide GC information. In this study, we developed a deep learning framework for GC image analysis, named dual-channel attention U-Net (DCAU-Net). Dual-channel convolution was used both to extract the overall image texture and to acquire the GC morphological characteristics. A global channel attention module was adopted by combining attention algorithms and channel-wise pooling. DCAU-Net showed 93.1% GC segmentation accuracy and 94.3% GC density estimation accuracy. Further application to both normal and ocular surface damage rabbit models revealed the spatial variations of both GC density and size in normal rabbits and the decreases of both GC density and size in damage rabbit models during recovery after acute damage. The GC analysis results were consistent with histology. Together with the non-invasive high-contrast imaging method, DCAU-Net would provide GC information for the diagnosis of ocular surface diseases.


Deep Learning , Eye Diseases , Lagomorpha , Animals , Rabbits , Goblet Cells/metabolism , Conjunctiva/pathology , Tears/metabolism , Eye Diseases/metabolism , Cell Count
6.
Sensors (Basel) ; 21(21)2021 Nov 05.
Article En | MEDLINE | ID: mdl-34770677

The non-invasive examination of conjunctival goblet cells using a microscope is a novel procedure for the diagnosis of ocular surface diseases. However, it is difficult to generate an all-in-focus image due to the curvature of the eyes and the limited focal depth of the microscope. The microscope acquires multiple images with the axial translation of focus, and the image stack must be processed. Thus, we propose a multi-focus image fusion method to generate an all-in-focus image from multiple microscopic images. First, a bandpass filter is applied to the source images and the focus areas are extracted using Laplacian transformation and thresholding with a morphological operation. Next, a self-adjusting guided filter is applied for the natural connections between local focus images. A window-size-updating method is adopted in the guided filter to reduce the number of parameters. This paper presents a novel algorithm that can operate for a large quantity of images (10 or more) and obtain an all-in-focus image. To quantitatively evaluate the proposed method, two different types of evaluation metrics are used: "full-reference" and "no-reference". The experimental results demonstrate that this algorithm is robust to noise and capable of preserving local focus information through focal area extraction. Additionally, the proposed method outperforms state-of-the-art approaches in terms of both visual effects and image quality assessments.


Algorithms , Image Processing, Computer-Assisted , Microscopy
7.
Article En | MEDLINE | ID: mdl-34574608

This study aims to determine why Korean parents provide adolescent children with continuous physical education through Taekwondo. The Q methodology was applied. The final 25 Q-samples were selected by composing the Q-population. Twenty parents who provided their children with Taekwondo education for more than 10 years were designated as the P-sample. Q-sorting was performed on the P-sample. Centroid factor analysis and varimax rotation were performed using version 2.35 of PQ method program. The study observed four factors with a total explanatory variance of 69%. Types 1 to 4 (N = 5, 7, 5, and 3) pertained to a powerful means of enhancing mental health, the driving force behind stable school life and social development, improvement in psychological and social areas for a successful transition to adulthood, and increased awareness of the values of Taekwondo and importance of physical activity, with eigenvalues of 4.59, 6.42, 3.16, and 1.18 and explanatory variances of 0.16, 0.32, 0.12, and 0.09, respectively. Furthermore, consensus statements for each type were investigated as Q18 and Q17. These findings supported the academic foundation of proper Taekwondo education in adolescence and confirmed it as a powerful means of exerting a positive impact on adulthood.


Martial Arts , Achievement , Adolescent , Adult , Child , Humans , Perception , Q-Sort , Republic of Korea
8.
Sensors (Basel) ; 21(17)2021 Sep 06.
Article En | MEDLINE | ID: mdl-34502862

In this paper, a simple printed cross-dipole (PCD) antenna to achieve a right-hand circular polarization (RHCP) at the L/S-band for direction finding (DF) systems is presented. The radiating part of the antenna consists of two printed dipoles that interlock with each other and are mounted orthogonally on a dual-layer printed reflector. To connect the feedlines of the dipole elements to the antenna's feed network, which is located on the backside of the reflector, a through-hole signal via (THSV) is employed as the signal interconnection instead of the mainstream approach of using coaxial bead conductor. This feeding technique provides a degree of freedom to control the impedance of the signal path between the feedlines and the feed network in the numerical simulation for improved matching conditions. The proposed THSV extending through the dual-layer printed reflector is more reliable, durable, and mechanically robust to stabilize the matching conditions of the fabricated antenna in contrast to the coaxial-based approach that is more susceptible to impedance mismatch due to solder fatigue. Thus, the proposed PCD antenna offers advantages of broadband, flexible impedance matching, and fabrication ease. The antenna exhibits an impedance bandwidth (IBW) of 59% (1.59-2.93 GHz), a 3-dB axial ratio bandwidth (ARBW) of 57% (1.5-2.7 GHz), and a peak of 7.5 dB within the operating frequency band.

9.
Curr Genet ; 67(4): 613-630, 2021 Aug.
Article En | MEDLINE | ID: mdl-33683401

Aspergillus nidulans produces cleistothecia as sexual reproductive organs in a process affected by genetic and external factors. To gain a deeper insight into A. nidulans sexual development, we performed comparative proteome analyses based on the wild type developmental periods. We identified sexual development-specific proteins with a more than twofold increase in production during hypoxia or the sexual period compared to the asexual period. Among the sexual development-specific proteins analyzed by gene-deletion experiments and functional assays, MpdA, a putative mannitol-1-phosphate 5-dehydrogenase, plays multiple roles in growth and differentiation of A. nidulans. The most distinct mpdA-deletion phenotype was ascosporogenesis failure. Genetic mpdA deletion resulted in small cleistothecia with no functional ascospores. Transcriptional analyses indicated that MpdA modulates the expression of key development- and meiosis-regulatory genes during sexual development. The mpdA deletion increased hyphal branching and decreased conidial heat resistance. Mannitol production in conidia showed no difference, whereas it was decreased in mycelia and sexual cultures. Addition of mannitol during vegetative growth recovered the defects in conidial heat resistance and ascospore genesis. Taken together, these results indicate that MpdA plays an important role in sexual development, hyphal branching, and conidial heat resistance in Aspergillus nidulans.


Aspergillus nidulans/genetics , Hyphae/genetics , Spores, Fungal/genetics , Sugar Alcohol Dehydrogenases/genetics , Aspergillus nidulans/growth & development , Aspergillus nidulans/pathogenicity , Gene Expression Regulation, Fungal/genetics , Hyphae/growth & development , Mannitol/metabolism , Meiosis/genetics , Sexual Development/genetics , Spores, Fungal/metabolism
10.
Opt Express ; 26(23): 29916-29930, 2018 Nov 12.
Article En | MEDLINE | ID: mdl-30469874

A delta-sigma-modulated intermediate-frequency-over-fiber (IFoF) transmission system assisted by a correlative-level coding technique is proposed and experimentally demonstrated. Unlike conventional delta-sigma IFoF systems with multiple output levels to achieve higher signal quality or larger capacity, a correlative-level encoder is exploited as a second modulator preceded by the delta-sigma modulator. The encoder compresses the bandwidth of the delta-sigma modulated signal by creating a correlation between adjacent signal symbols. As a result, the sampling frequency of the delta-sigma modulator in the proposed system can be increased beyond the transmission bandwidth of the IFoF system, considerably improving the in-band signal quality and the transmission capacity over the conventional multi-level approach. This is because the quantization noise from the delta-sigma modulation in the proposed scheme is more aggressively pushed away from the signal bandwidth with the high sampling frequency. According to experimental results, the proposed link provides at least a 40% larger transmission capacity for similar in-band signal quality or 2.1% better average EVM performance for the same capacity than the conventional four-level pulse-amplitude-modulation delta-sigma IFoF systems.

11.
Opt Express ; 25(7): 8335-8349, 2017 Apr 03.
Article En | MEDLINE | ID: mdl-28380948

Two ∆Σ-modulated digital radio-over-fiber (DRoF) transmission systems that employ a multi-pulse Manchester encoder are proposed and experimentally evaluated. With a two-step modulation process comprised of ∆Σ modulation and multi-pulse Manchester encoding, a high frequency replica or image of a ∆Σ-digitized analog communication signal can be transmitted without significant power loss. This is achieved by exploiting the spectral characteristics of the modified Manchester code. For comparative analysis, a conventional ∆Σ-modulation-based DRoF system is also evaluated. Based on the evaluation results, the proposed DRoF systems more significantly improve the reliability and flexibility of the RoF system by providing higher power margins or by making the DRoF system implementation more cost-effective and easier to perform on account of the low-frequency requirement for electronics and optical transceivers.

13.
J Am Chem Soc ; 133(20): 7764-85, 2011 May 25.
Article En | MEDLINE | ID: mdl-21542608

A new kind of organic-inorganic hybrid polymer, poly(tetraphenyl)silole siloxane, was invented and synthesized for realization of its unique charge trap properties. The organic portions consisting of (tetraphenyl)silole rings were responsible for negative charge trapping, while the Si-O-Si inorganic linkages provided the intrachain energy barrier for controlling electron transport. The polysilole siloxane dielectric thin films were fabricated by spin-coating and curing of the polymers, followed by characterization with spectroscopic ellipsometry (SE), near edge X-ray absorption fine structure spectroscopy (NEXAFS), and photoemission spectroscopy (PES). The abrupt increase in density and decrease in thickness of the thin film at a curing temperature of 100 °C was attributed to a thermodynamically preferred state in the nanoscopic arrangement of the polymer chains; this was due to cofacial π-π interactions in a skewed manner between peripheral phenyl groups of the (tetraphenyl)silole rings of the adjacent polymer chains. Using the NEXAFS spectrum to assess high electron affinity, the LUMO energy level of the dielectric thin film cured at 150 °C was positioned 1 eV above the Fermi energy level (E(F)). The electron trapping of the dielectric thin films was confirmed from the positive flat band shift (ΔV(FB)) in the capacitance-voltage (C-V) measurements performed within the metal-insulator-semiconductor (MIS) device structure, which strongly verified the polymer design concept. From the simple kinetics model of the electron transport, it was proposed that the flat band shift (ΔV(FB)) or trap density of the negative charges (|ρ|) was logarithmically proportional to the decay constant (ß) for the electron-tunneling process. When a phenyl group of a silole ring in a polymer chain was inserted into the two available phenyl groups of another silole ring in another polymer chain, the electron transfer between the groups was enhanced, decreasing the trap density of the negative charges (|ρ|). For the thermodynamically preferred state generating the high refractive index, the distance between the two phenyl groups of the adjacent polymer chains was estimated to be in the range of 0.27-0.36 nm.

14.
J Nanosci Nanotechnol ; 11(2): 1328-32, 2011 Feb.
Article En | MEDLINE | ID: mdl-21456181

Porous silicon (PSi) smart particles containing 20(S)-Camptothecin (CPT)-functionalized germanium nanoparticles (Ge-NPs) for a noble drug delivery system were developed. PSi samples were prepared by anodization of a highly doped P(++)-type Si wafer in ethanolic HF solution using a platinum-meshed counter electrode. In this work, PSi was generated by an electrochemical etching of two discrete porous multilayered dielectric mirrors into Si, a top layer was referred to as the "DBR" multilayer, and a bottom layer was the "host" layer intended to infuse CPT-functionalized Ge-NPs. The DBR layer was chemically further passivated with (3-aminopropyl)trimethoxysilane groups. Resulting PSi was removed from the Si substrate by an applying of electropolishing current. CPT-functionalized Ge-NPs were infused into the host layer of PSi free-standing film. Samples were then made into particles by ultrasonic fracture in organic solutions. PSi smart particles were characterized by FE-SEM, FT-IR, EDX, UV-vis absorption, and fluorescence spectroscopy. PSi smart particles containing CPT-functionalized Ge-NPs displayed a linear release profile for the first 12 h, and then perfectly released CPT-functionalized Ge-NPs for 18 h.


Camptothecin/administration & dosage , Germanium/chemistry , Metal Nanoparticles/chemistry , Silicon/chemistry , Drug Delivery Systems , Electrochemical Techniques , Metal Nanoparticles/ultrastructure , Microscopy, Electron, Scanning , Nanotechnology , Spectrophotometry , Spectroscopy, Fourier Transform Infrared
15.
J Nanosci Nanotechnol ; 11(2): 1368-72, 2011 Feb.
Article En | MEDLINE | ID: mdl-21456190

New photoluminescent and nanoscale polygermole nanoaggregates for the detection of 2,4,6-trinitrotoluene (TNT) were developed by using aggregation-induced emission property. Polygermole nanoaggregates displaying diameter of 40 nm exhibited that photoluminescence (PL) intensity of emission band was increased about 730% when the water fraction was increased to 90% by volume. Relative PL efficiency of polygermole nanoaggregates was exponentially increased to the percent of water fraction and particle diameter was dependent on solvent composition. Particle size of polygermole nanoaggregates was tuned by controlling the water fraction by volume. PL intensity of polygermole nanoaggregates was not changed over a month. This indicated that polygermole nanoaggregates showed neither further aggregation nor degradation. Detection of TNT was achieved from the measuring of quenching PL of polygermole nanoaggregates by adding the TNT A linear Stern-Volmer relationship was observed for the detection of TNT.

16.
J Nanosci Nanotechnol ; 10(5): 3266-70, 2010 May.
Article En | MEDLINE | ID: mdl-20358936

Novel porous Si exhibiting dual optical properties, both Fabry-Perot fringe (optical reflectivity) and photoluminescence, were developed and used as chemical sensors. Porous Si samples were prepared by an electrochemical etch of p-type silicon under the illumination with a 300 W tungsten filament bulb for the duration of etch. The surface of porous Si was characterized by FT-IR instrument. The porosity of samples was about 80%. Both reflectivity and photoluminescence were simultaneously measured under the exposure of organic vapors. The shift of Fabry-Perot fringe to the longer wavelength under the exposure of chloroform vapors was obtained. The steady-state photoluminescence spectra and quenching photoluminescence under the exposure of various organic vapors were obtained. A set of organic compounds were analyzed by both quenching photoluminescence and change of optical thickness.

17.
J Nanosci Nanotechnol ; 10(5): 3375-9, 2010 May.
Article En | MEDLINE | ID: mdl-20358960

Optically encoded smart particles were prepared for noble drug delivery materials. Distributed Bragg reflector (DBR) porous silicon (PSi) was generated by applying a computer-generated pseudo-square wave current waveform. This DBR PSi film was lifted off from the Si substrate and thermally oxidized to convert PSi to porous silicon dioxide (PSD). DBR PSD film was derivatized with 20(S)-Camptothecin (CPT) and fractured by ultrasono-method to give smart particles. DBR PSD smart particles exhibited a sharp photonic band gap in the optical reflectivity spectrum. Optical characteristic of PSD smart particles retained DBR photonic property in aqueous buffer solution. The release of CPT and change of reflection wavelength were measured by UV-vis and reflectance spectrometer, respectively. The intensity of differential peak from reflection resonances of the smart particles was increased with a drug release. The blue shift of reflection peak resulted in the decrease of refractive index of PSD smart particles during the drug release. The concentration of released drug exhibited an linear relationship with a release time.


Antineoplastic Agents, Phytogenic/chemistry , Camptothecin/analogs & derivatives , Drug Carriers/chemistry , Nanoparticles/chemistry , Silicon/chemistry , Antineoplastic Agents, Phytogenic/administration & dosage , Camptothecin/administration & dosage , Camptothecin/chemistry , Drug Compounding/methods , Materials Testing , Nanoparticles/ultrastructure , Particle Size
18.
J Nanosci Nanotechnol ; 10(5): 3444-8, 2010 May.
Article En | MEDLINE | ID: mdl-20358975

Photonic polymer composite materials exhibiting both reflective and magnetic properties were prepared by the replication of rugate porous silicon (PS) using polystyrene and magnetite nanoparticle (Fe3O4). Rugate PS prepared by applying a computer-generated pseudo-sinusoidal current waveform resulted in a mirror with high reflectivity in a specific narrow spectral region and served as a template for replicating its nanostructure with polystyrene containing the magnetic nanoparticles of magnetite. The composite films replicated a sharp photonic resonance with full-width at half maximum (FWHM) of 20 nm from rugate PS in the reflectivity spectrum as well as displayed a magnetic property of magnetite nanoparticles in SQUID magnetometry. Optical characteristics of composite films indicated that the surface of polymer film had a negative structure of rugate PS. The composite films were stable in aqueous solutions for several days without any degradation.

19.
J Nanosci Nanotechnol ; 10(5): 3557-61, 2010 May.
Article En | MEDLINE | ID: mdl-20358999

New synthetic route and characterization of alkyl-capped nanocrystalline silicon (R-n-Si) were achieved from the reaction of silicon tetrachloride with sodium/benzophenone ketal, followed by n-butyllithium. Optical characteristics of silicon nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), and photoluminescence (PL) spectroscopy. Butyl-capped silicon nanoparticles exhibited an emission band at 410 nm with excitation wavelength of 360 nm. Average size of n-butyl-capped silicon nanoparticles was obtained by particle size analyzer (PSA) and transmission electron microscopy (TEM). Average size of n-butyl-capped Si nanoparticles was about 6.5 nm.

20.
J Nanosci Nanotechnol ; 10(5): 3590-4, 2010 May.
Article En | MEDLINE | ID: mdl-20359006

Multi-encoded rugate porous silicon (PSi)-based optical biosensor was developed to specify the biomolecules. Multi-encoded rugate PSi was generated by an electrochemical etching of silicon wafer using an electrode configuration in aqueous ethanolic HF solution. Multi-encoded rugate PSi displayed three very sharp reflection bands whose reflection maxima varied spatially across the PSi. The sensor system studied consisted of a multilayer of PSi modified with biotin. The system was probed with various fragments of an aqueous protein analyte. The sensor operates by measurement of the reflection peaks in the white light reflection spectrum from the PSi layer. When the biotin-derivatized rugate PSi was exposed to protein in phosphate buffer solution (PBS), the molecular binding caused a change of its refractive index is detected as a shift in wavelength of these reflection peaks. A red-shift of reflective spectra were observed, when the biotin-modified rugate PSi was exposed to a flow of protein.


Biosensing Techniques/instrumentation , Immunoassay/instrumentation , Interferometry/instrumentation , Refractometry/instrumentation , Silicon/chemistry , Equipment Design , Equipment Failure Analysis , Porosity
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