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1.
Biomed Mater ; 19(2)2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38364287

ABSTRACT

The plasma technique has been widely used to modify the surfaces of materials. The purpose of this study was to evaluate the probability of controlling the prednisolone delivery velocity on a polylactic acid (PLA) surface modified by plasma surface treatment. Surface modification of PLA was performed at a low-pressure radio frequency under conditions of 100 W power, 50 mTorr chamber pressure, 100-200 sccm of flow rate, and Ar, O2, and CH4gases. The plasma surface-modified PLA was characterized using scanning emission microscope, x-ray photoelectron spectroscopy (XPS), and contact angle measurements.In vitroevaluations were performed to determine cellular response, drug release behavior, and anti-inflammatory effects. The PLA surface morphology was changed to a porous structure (with a depth of approximately 100 µm) and the surface roughness was also significantly increased. The XPS results demonstrated higher oxygenized carbon contents than those in the non-treated PLA group. The prednisolone holding capacity increased and the release was relatively prolonged in the surface-modified PLA group compared to that in the non-treated PLA group. In addition, cell migration and proliferation significantly increased after PLA treatment alone. The activity of cytokines such as cyclooxygenase-2 (COX-2), tumor necrosis factor-a (TNF-α), interleukin (IL-1ß), and IL-6 were considerably reduced in the plasma-treated and prednisolone holding group. Taken together, surface-modified PLA by plasma can provide an alternative approach to conventional physicochemical approaches for sustained anti-inflammatory drug release.


Subject(s)
Polyesters , Polymers , Drug Liberation , Polymers/chemistry , Polyesters/chemistry , Gases , Prednisolone
2.
Adv Sci (Weinh) ; 11(13): e2306798, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38240455

ABSTRACT

Solution-processed low-bandgap semiconductors are crucial to next-generation infrared (IR) detection for various applications, such as autonomous driving, virtual reality, recognitions, and quantum communications. In particular, III-V group colloidal quantum dots (CQDs) are interesting as nontoxic bandgap-tunable materials and suitable for IR absorbers; however, the device performance is still lower than that of Pb-based devices. Herein, a universal surface-passivation method of InAs CQDs enabled by intermediate phase transfer (IPT), a preliminary process that exchanges native ligands with aromatic ligands on the CQD surface is presented. IPT yields highly stable CQD ink. In particular, desirable surface ligands with various reactivities can be obtained by dispersing them in green solvents. Furthermore, CQD near-infrared (NIR) photodetectors are demonstrated using solution processes. Careful surface ligand control via IPT is revealed that enables the modulation of surface-mediated photomultiplication, resulting in a notable gain control up to ≈10 with a fast rise/fall response time (≈12/36 ns). Considering the figure of merit (FOM), EQE versus response time (or -3 dB bandwidth), the optimal CQD photodiode yields one of the highest FOMs among all previously reported solution-processed nontoxic semiconductors comprising organics, perovskites, and CQDs in the NIR wavelength range.

3.
J Voice ; 37(1): 142.e5-142.e12, 2023 Jan.
Article in English | MEDLINE | ID: mdl-33199080

ABSTRACT

OBJECTIVES: The purposes of this study were (1) to analyze the usefulness of self-report questionnaires, acoustic analysis, and auditory perceptual assessment for screening voice problems; and (2) to develop a new model for predicting a comprehensive voice severity using multi-assessment. METHODS: A total of 306 voice samples were analyzed in this study (typical group, n = 72; dysphonia group, n = 234). We performed a receiver operating characteristic analysis to determine the cutoff values of auditory perceptual assessments (visual analog scale), acoustic parameters (spectral- and cepstral-based analyses), and self-report questionnaires for screening voice disorders. We also performed a stepwise multiple regression analysis to verify which combination of parameters (acoustic parameters, and self-report questionnaires) could best predict perceived voice severity. RESULTS: We verified that most of the variables analyzed were useful for voice evaluation, and found to be useful for screening voice problems. Of these, a five-variable model was a useful to predict perceived voice severity (mean R2 = .807). The five-variable model consisted of acoustic parameters based on cepstral analysis (cepstral peak prominences in connected speech and sustained vowel task, and low versus high-frequency spectral energy ratio in connected speech task) and self-report questionnaires (total score of the Voice Handicap Index, and rumination score of the Voice Catastrophization Index). CONCLUSION: We verified that most of the variables were useful for screening dysphonia and five-variable model was a useful to predict perceived voice severity. The five-variable model could be used as an objective criterion for predicting voice severity.


Subject(s)
Dysphonia , Voice , Humans , Dysphonia/diagnosis , Speech Acoustics , Speech , Acoustics , Speech Production Measurement , Severity of Illness Index
4.
Int J Mol Sci ; 23(22)2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36430279

ABSTRACT

The aim of this study is to synthesize phenethyl-conjugated chitosan oligosaccharide (COS) (abbreviated as ChitoPEITC) conjugates and then fabricate chlorin E6 (Ce6)-incorporated nanophotosensitizers for photodynamic therapy (PDT) of HCT-116 colon carcinoma cells. PEITC was conjugated with the amine group of COS. Ce6-incorporated nanophotosensitizers using ChitoPEITC (ChitoPEITC nanophotosensitizers) were fabricated by dialysis method. 1H nuclear magnetic resonance (NMR) spectra showed that specific peaks of COS and PEITC were observed at ChitoPEITC conjugates. Transmission electron microscope (TEM) confirmed that ChitoPEITC nanophotosensitizers have spherical shapes with small hydrodynamic diameters less than 200 nm. The higher PEITC contents in the ChitoPEITC copolymer resulted in a slower release rate of Ce6 from nanophotosensitizers. Furthermore, the higher Ce6 contents resulted in a slower release rate of Ce6. In cell culture study, ChitoPEITC nanophotosensitizers showed low toxicity against normal CCD986Sk human skin fibroblast cells and HCT-116 human colon carcinoma cells in the absence of light irradiation. ChitoPEITC nanophotosensitizers showed a significantly higher Ce6 uptake ratio than that of free Ce6. Under light irradiation, cellular reactive oxygen species (ROS) production of nanophotosensitizers was significantly higher than that of free Ce6. Especially, PEITC and/or ChitoPEITC themselves contributed to the production of cellular ROS regardless of light irradiation. ChitoPEITC nanophotosensitizers showed significantly higher PDT efficacy against HCT-116 cells than that of free Ce6. These results indicate that ChitoPEITC nanophotosensitizers have superior potential in Ce6 uptake, ROS production and PDT efficacy. In the HCT-116 cell-bearing mice tumor-xenograft model, ChitoPEITC nanophotosensitizers efficiently inhibited growth of tumor volume rather than free Ce6. In the animal imaging study, ChitoPEITC nanophotosensitizers were concentrated in the tumor tissue, i.e., fluorescence intensity in the tumor tissue was stronger than that of other tissues. We suggest that ChitoPEITC nanophotosensitizers are a promising candidate for the treatment of human colon cancer cells.


Subject(s)
Carcinoma , Chitosan , Colonic Neoplasms , Humans , Mice , Animals , Reactive Oxygen Species , Colonic Neoplasms/drug therapy , Oligosaccharides
5.
Materials (Basel) ; 14(24)2021 Dec 16.
Article in English | MEDLINE | ID: mdl-34947382

ABSTRACT

Corrosion of nitinol (NiTi) is a major factor in the failure of implantable materials. Recently, as the importance of corrosion of metals has increased, testing according to international guidelines is essential. The purpose of this study was to evaluate the corrosion resistance of NiTi wire through heat treatment and passivation process. In this study, NiTi wire used two commercially available products and a self-manufactured stent. Experimental consideration was carried out according to ASTM standards. Heat treatment was carried out in an air or a salt furnace, and the corrosion was measured after additional process, such as passivation and scratch tests. As a result, the metal potential was rapidly decreased in the air furnace group. On the other hand, the potential of wires was dramatically increased in the salt furnace group compared to the air furnace group. The dislocation decreased below the acceptance criteria (>600 mV) within 60 s of heat treatment time in the air furnace. Moreover, the potential was dramatically improved, even after only 20 min of passivation treatment (1076 mV, 442% compared to the non-passivated group), and it continued to rise until 180 min. This phenomenon was similarly observed in the group of self-manufactured stents. The potential slightly decreased by the scratch process (93.1%) was significantly reduced by the air furnace process (315 mV, 24.4% of the nontreated group). In the passivated group of the air furnace sample with reduced potential, the potential was restored to the level before the air furnace (scratch stage) (1032 mV). In conclusion, the heat treatment is preferably carried out in a salt furnace rather than an air furnace, and the passivation process can be an advantageous tool to improve corrosion resistance by suppressing the oxidation process.

6.
Biomater Res ; 25(1): 30, 2021 Sep 26.
Article in English | MEDLINE | ID: mdl-34565474

ABSTRACT

OBJECTIVE: Various surface modification techniques that can further improve the function and usability of stainless steel as a medical device have been reported. In the present study, the physical and biological properties of nanoporous stainless steel as well as its usefulness for drug delivery were assessed. METHODS: The specimen was prepared with a circular disk shape (15 mm in diameter and 1 mm in thickness). The disk was subjected to electropolishing at a constant voltage of 20 V and 10 A for 10 min in an acidic environment (50% H2SO4). Everolimus (EVL) was used as a testing drug for drug-loading capacity of the material surface and release kinetics. The physiobiological properties of the material were assessed using platelet adhesion, and smooth muscle cell (SMC) adhesion, migration, and proliferation assays. RESULTS: The surface roughness of the postpolishing group was greater than that of the nonpolishing group. Platelet adhesion and SMC adhesion and migration were inhibited in the postpolishing group compared to those in the prepolishing group. In the postpolishing group, the total amount of EVL on the surface (i.e., drug storage rate) was higher and the drug release rate was lower, with half the amount of the EVL released within 4 days compared with only 1 day for that of the prepolishing group. CONCLUSION: Taken together, this stainless steel with a nanoporous surface could be used as a medical device for controlling cellular responses and carrying drugs.

7.
J Voice ; 35(2): 328.e11-328.e22, 2021 Mar.
Article in English | MEDLINE | ID: mdl-31640898

ABSTRACT

OBJECTIVES: This study investigated whether there are differences in the discriminatory power of cepstral analysis according to the voiced-segment extraction method and voice tasks used for identifying dysphonic and normophonic Korean individuals. MATERIALS AND METHODS: A total of 2,863 subjects (2,595 subjects with and 268 subjects without dysphonia) were included in this study. The 3-second sustained vowel (SV) /a/ and one sentence of "Sanchaek" were edited and analyzed using Praat scripts. Cepstral analyses (cepstral peak prominence [CPP], smoothed cepstral peak prominence [CPPS], and low/high spectral ratio [LHRatio]) were performed using three voice tasks, namely, SV, continuous speech (CS), and extracted continuous speech (EXT) samples. Additionally, auditory-perceptual (A-P) assessments were performed by three speech language pathologists. RESULTS: Significant differences were found between dysphonic and normophonic voice groups for all cepstral parameters, except the LHRatio_EXT. Cepstral measurements of both SV and CS were highly correlated with A-P ratings. Furthermore, the diagnostic predictive power of CPP and CPPS for CS using the area under the receiver operating characteristic curve (AUC) was >0.919, the positive likelihood ratio (LR+) was ≥6.85, and the negative likelihood ratio (LR-) was ≤0.23. Additionally, for EXT, the AUC was >0.816, LR+ was 3.10, and LR- was ≤0.33. CONCLUSION: Both CS and EXT can predict dysphonia relatively well (r > 0.816). EXT showed lower predictability than the original sample (CS) analysis. Subsequent studies should implement voiced-segment extraction methods using various algorithms.


Subject(s)
Dysphonia , Language , Dysphonia/diagnosis , Humans , Republic of Korea , Speech Acoustics , Speech Production Measurement , Voice Quality
8.
Biomater Res ; 24: 4, 2020.
Article in English | MEDLINE | ID: mdl-31998531

ABSTRACT

BACKGROUND: The aim of this study was to characterize the mechanical and physio-biological properties of peptide-coated stent (PCS) compared to commercialized drug-eluting stents (DESs). METHODS: WKYMVm (Trp-Lys-Tyr-Met-Val-D-Met), a stimulating peptide for homing endothelial colony-forming cell was specially synthesized and coated to bare metal stent (BMS) by dopamine-derived coordinated bond. Biological effects of PCS were investigated by endothelial cell proliferation assay and pre-clinical animal study. And mechanical properties were examined by various experiment. RESULTS: The peptide was well-coated to BMS and was maintained and delivered to 21 and 7 days in vitro and in vivo, respectively. Moreover, the proliferation of endothelial cell in PCS group was increased (approximately 36.4 ± 5.77%) in PCS group at 7 day of culture compare to BMS. Although, the radial force of PCS was moderated among study group. The flexibility of PCS was (0.49 ± 0.082 N) was greatest among study group. PCS did not show the outstanding performance in recoil and foreshortening test (3.1 ± 0.22% and 2.1 ± 0.06%, respectively), which was the reasonable result under the guide line of FDA (less than 7.0%). The nominal pressure (3.0 mm in a diameter) of PCS established by compliance analysis was 9 atm. The changing of PCS diameter by expansion was similar to other DESs, which is less than 10 atm of pressure for the nominal pressure. CONCLUSIONS: These results suggest that the PCS is not inferior to commercialized DES. In addition, since the PCS was fabricated as polymer-free process, secondary coating with polymer-based immunosuppressive drugs such as -limus derivatives may possible.

9.
J Voice ; 34(3): 489.e11-489.e19, 2020 May.
Article in English | MEDLINE | ID: mdl-30527706

ABSTRACT

OBJECTIVES: The acoustic voice quality index (AVQI) is a specific acoustic indicator designed to objectively estimate dysphonia severity and measure the values of acoustic parameters based on the diagnostic category. This study compared the performance of two AVQI versions (2.02 and 3.01, v2 and v3) and PraatCPPS using a voice sample of Korean population. MATERIALS AND METHODS: Voice samples for sustained vowel and connected speech were elicited from 2257 patients across 14 diagnostic categories. Auditory-perceptual (A-P) assessments of dysphonia severity were compared to acoustic parameters of severity derived from two versions of the AVQI (v2 and v3) as well as the PraatCPPS. RESULTS: The AVQI-estimated severity (v2 and v3) and PraatCPPS severity for concatenated voice samples strongly correlated with each other and were significantly associated with A-P ratings. The AVQI (v2 and v3) and PraatCPPS showed high reliability in differentiating between pathological voice disorders. CONCLUSION: The AVQI (v2 and v3) and PraatCPPS were strongly correlated with the A-P ratings and provided valid estimates of dysphonia severity. However, the associations of the A-P ratings with the AVQIv2 were significantly stronger than those with the AVQIv3 and PraatCPPS, suggesting that the V2 outperformed the V3 and PraatCPPS.


Subject(s)
Acoustics , Dysphonia/diagnosis , Speech Acoustics , Speech Production Measurement , Voice Quality , Dysphonia/physiopathology , Female , Humans , Male , Observer Variation , Predictive Value of Tests , Severity of Illness Index
10.
J Speech Lang Hear Res ; 62(10): 3643-3654, 2019 10 25.
Article in English | MEDLINE | ID: mdl-31577518

ABSTRACT

Purpose The purpose of this study was to investigate the characteristics of diplophonia using an auditory perception and multimodal simultaneous examination, which included sound waveform analysis, electroglottography (EGG), digital kymography (DKG), and 2-dimensional scanning digital kymography (2D DKG). Additionally, we compared the diagnostic accuracy of each method using a binary classifier in confusion matrix and convenience of discrimination, based on the time required for interpretation. Method One normophonic male, 12 patients with diplophonia, and 12 dysphonia patients without diplophonia were enrolled. A multimodal simultaneous evaluation was used to analyze the vibration pattern of diplophonia. Sensitivity, specificity, accuracy, area under the curve, and interpretation time were used to compare the various diagnostic methods. Discrimination was determined by 3 raters. Results There are 3 types of asymmetric vibratory patterns in diplophonia. The types are based on the oscillators vibrating at different frequencies: asymmetry of the left and right cords (6 subjects with unilateral palsy and 1 subject with vocal polyps), asymmetry of anterior and posterior cords (2 subjects with vocal polyps), and asymmetry of true and false cords (3 subjects with muscle tension dysphonia). All evaluation methods were useful as diagnostic tools, with all areas under the curve > .70. The diagnostic accuracy was highest with DKG (95.83%), followed by 2D DKG (83.33%), EGG (81.94%), auditory-perceptual evaluation (80.56%), and sound waveform (77.78%). The interpretation time was the shortest for auditory-perceptual evaluation (6.07 ± 1.34 s), followed by 2D DKG (10.04 ± 3.00 s), EGG (12.49 ± 2.76 s), and DKG (13.53 ± 2.60 s). Conclusions Auditory-perceptual judgment was the easiest and fastest method for experienced raters, but its diagnostic accuracy was lower than that of DKG or 2D DKG. The diagnostic accuracy of DKG was the highest, but 2D DKG allowed rapid interpretation and showed relatively high diagnostic accuracy, except in cases with space-occupying lesions. Supplemental Material https://doi.org/10.23641/asha.9911786.


Subject(s)
Dysphonia/diagnostic imaging , Kymography/methods , Laryngeal Diseases/diagnostic imaging , Polyps/diagnostic imaging , Adult , Area Under Curve , Female , Glottis/diagnostic imaging , Humans , Male , Middle Aged , Observer Variation , Phonation , Sensitivity and Specificity , Vibration , Wavelet Analysis
11.
J Laparoendosc Adv Surg Tech A ; 29(7): 953-957, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30990359

ABSTRACT

Objective: This study aimed to evaluate the feasibility of the gasless transoral endoscopic thyroidectomy vestibular approach (TOETVA) using the Thyroidoscope, developed to maintain the surgical working space without CO2 insufflation. Materials and Methods: To prevent a potentially fatal CO2-related complication, we developed a retractable device, named the Thyroidoscope, which could maintain the surgical working space without CO2 insufflation. We conducted a preclinical cadaver study to evaluate its use in gasless TOETVA. Results: The Thyroidoscope provided a secure surgical field and stable image on the screen. We could successfully identify the recurrent laryngeal nerve, parathyroid gland, and other critical structures without inadvertent injury due to insertion of the Thyroidoscope. Conclusions: The Thyroidoscope provides sufficient working space to perform transoral thyroid surgery without the need for CO2 insufflation. Gasless TOETVA with the Thyroidoscope seems to be feasible and safe.


Subject(s)
Natural Orifice Endoscopic Surgery/instrumentation , Thyroid Gland/surgery , Thyroidectomy/methods , Cadaver , Feasibility Studies , Humans , Natural Orifice Endoscopic Surgery/methods , Parathyroid Glands/diagnostic imaging , Recurrent Laryngeal Nerve/diagnostic imaging
12.
J Biomater Appl ; 33(9): 1232-1241, 2019 04.
Article in English | MEDLINE | ID: mdl-30776991

ABSTRACT

Everolimus inhibits stent restenosis and the WKYMV (fluorescein isothiocyanate) peptide promotes endothelial homing. Dextran is a natural polymer that is widely used as a pharmaceutical agent. The purpose of this study was to develop a double-drug-coated stent using a bidirectional coating system and to examine the surface shape with in vitro experiments. Stent length was 16 mm and strut thickness was 70 µm (Chonnam National University Hospital Tiger stent). Optical and scanning electron microscopy showed good coating without cracks or bubbles. Fluorescein isothiocyanate-peptide was dip-coated on the lumen and the abluminal surface was coated with everolimus and dextran. Stents were coated with dextran, everolimus, or everolimus-dextran. The radial force and flexibility were measured to determine the mechanical properties. Contact angle testing was performed in all groups. Dextran and peptide as hydrophilic substances and everolimus as a hydrophobic substance were each coated on cover glasses (cobalt-chromium). A10 and human umbilical vein endothelial cells were used in the experiments. Water and dimethyl sulfoxide served as a control, and three drug groups were tested: peptide-everolimus, everolimus-dextran, and peptide-everolimus-dextran. Immunocytochemistry was performed to assess cell adhesion. Light intensity was plotted according to the average on nuclear staining. Experiments were conducted using 5-bromo-2'-deoxyuridine to investigate A10 and human umbilical vein endothelial cell proliferation. Cell adhesion and proliferation of peptide-everolimus-dextran were inhibited at A10, and human umbilical vein endothelial cell was found to proliferate with cell adhesion. On conclusion, dextran and peptide-everolimus bidirectional stent is effective in re-endothelialization and inhibition of cell proliferation.


Subject(s)
Dextrans/administration & dosage , Drug-Eluting Stents , Everolimus/administration & dosage , Oligopeptides/administration & dosage , Animals , Cell Adhesion/drug effects , Cell Line , Cell Proliferation/drug effects , Dextrans/chemistry , Dextrans/pharmacology , Drug Delivery Systems , Everolimus/chemistry , Everolimus/pharmacology , Human Umbilical Vein Endothelial Cells , Humans , Hydrophobic and Hydrophilic Interactions , Oligopeptides/chemistry , Oligopeptides/pharmacology , Rats
13.
J Voice ; 33(3): 346-351, 2019 May.
Article in English | MEDLINE | ID: mdl-29277350

ABSTRACT

BACKGROUND: A digital kymogram shows real images of vocal fold vibration. However, DKG is difficult to use in clinical practice because the recorded image cannot be seen instantaneously after examination, as considerable encoding time is required to visualize a digital kymogram. In addition, frame-by frame analysis should be implemented to evaluate high-speed videoendoscopy data, but is time- and labor-intensive. PURPOSE: The purpose of the study was to validate the clinical practicability of a real-time multislice digital kymographic system developed by the authors. We analyzed the promptness and accuracy of the examination before and after intracordal injections in patients with unilateral vocal fold paralysis. METHODS: To assess the clinical applicability of this system, six patients with unilateral vocal fold paralysis were selected. Real-time DKG was performed before and immediately after intracordal injection. We observed changes in the digital kymogram after the intracordal injection. RESULTS: Using this system, 10 scanning lines and up to five vertical pixel row could be obtained in real time, and the maximum acquisition time for the DKG image was 10 seconds. A digital kymogram of the patients could be instantaneously acquired, and whether the intracordal injection was appropriate or not. CONCLUSION: This article is the first validation study after the development of the real-time multislice digital kymographic system. Our system may be a promising tool in clinical practice for immediate assessment of the vibratory patterns of the vocal cords. More research is necessary for further clinical validation.


Subject(s)
Electrokymography/instrumentation , Phonation , Vocal Cord Paralysis/diagnostic imaging , Vocal Cords/diagnostic imaging , Adult , Aged , Case-Control Studies , Feasibility Studies , Female , Humans , Injections , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Time Factors , Treatment Outcome , Vibration , Vocal Cord Paralysis/physiopathology , Vocal Cord Paralysis/therapy , Vocal Cords/physiopathology
14.
J Voice ; 33(4): 554-560, 2019 Jul.
Article in English | MEDLINE | ID: mdl-29395330

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the clinical feasibility and diagnostic accuracy of two-dimensional scanning digital kymography (2D DKG) in patients with vocal cord atrophy before and after treatment. MATERIALS AND METHODS: We analyzed the characteristics of vocal fold vibration in five patients with unilateral vocal fold paralysis and five patients with presbyphonia. In patients with vocal cord paralysis, the status before and after intracordal injection was compared. Furthermore, in patients with presbyphonia, we compared the status before and after voice therapy (Seong-Tae Kim's laryngeal calibration technique). Quantitative parameters such as amplitude and phase symmetry indices, jitter, shimmer, noise-to-harmonic ratio, and maximum phonation time and qualitative parameters such as Voice Handicap Index, glottal gap, amplitude, and phase difference were used to evaluate the pre- and post-treatment status. RESULTS: In cases of vocal cord paralysis, vibratory changes of the vocal folds before and after intracordal injection could be identified immediately using 2D DKG. In overcorrection cases, all of the measured parameters were poor except for improvement of the glottal gap. In addition, 2D DKG showed appropriately the changes in vocal cord vibration before and after voice therapy in patients with presbyphonia. CONCLUSION: Two-dimensional DKG may be a useful diagnostic tool in evaluation of the vibratory characteristics of entire vocal cords. In addition, it may also play a role in providing a decision for treatment modalities.


Subject(s)
Dysphonia/diagnostic imaging , Kymography/methods , Laryngeal Diseases/diagnostic imaging , Phonation , Vocal Cord Paralysis/diagnostic imaging , Vocal Cords/diagnostic imaging , Adult , Aged , Atrophy , Dysphonia/pathology , Dysphonia/physiopathology , Dysphonia/therapy , Feasibility Studies , Female , Humans , Laryngeal Diseases/pathology , Laryngeal Diseases/physiopathology , Laryngeal Diseases/therapy , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Treatment Outcome , Vibration , Vocal Cord Paralysis/pathology , Vocal Cord Paralysis/physiopathology , Vocal Cord Paralysis/therapy , Vocal Cords/pathology , Vocal Cords/physiopathology , Voice Training
15.
J Voice ; 33(6): 948.e1-948.e9, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30076095

ABSTRACT

OBJECTIVE: The purpose of this study was to explore the concurrent validity of the Acoustic Voice Quality Index (AVQI) in a Korean population. We investigated the feasibility of its cutoff values and diagnostic accuracy in discriminating between normal and dysphonic voices. MATERIALS AND METHODS: A total of 1,524 native Korean subjects with normal voices (n = 113) and with voice disorders (n = 1,411) were asked to speak and sustain the vowel "a" and to read the Korean text "Walk" aloud. A 2-second mid-speech portion of the sustained vowel sound and two sentences (with 26 syllables) were edited and concatenated, and the AVQI was calculated. Additionally, two auditory-perceptual assessments, namely the Grade, Roughness, Breathiness, Asthenia, Strain scale, and the Consensus Auditory-Perceptual Evaluation of Voice were used by five speech language pathologists to rate the severity of dysphonia. RESULTS: Both auditory-perceptual assessments showed high confidence levels among the five speech language pathologists. The AVQI correlated with grade (G) and overall severity (OS). There were statistically significant differences in AVQI, G, and OS between normal and pathological speech groups. In the receiver operating characteristic curve analysis, AVQI, G, and OS cutoff values were <3.33, <0.00, and <22.00, respectively. The receiver operating characteristic curve analysis indicated that AVQI had excellent diagnostic accuracy for discriminating between normal and dysphonic voices (area under the curve: 0.970-0.977). CONCLUSIONS: We demonstrated the concurrent validity of AVQI as a promising tool for assessing overall voice quality and quantifying dysphonia in a Korean-speaking population.


Subject(s)
Dysphonia/diagnosis , Language , Speech Production Measurement , Speech , Voice Quality , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Child , Dysphonia/physiopathology , Dysphonia/psychology , Feasibility Studies , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Republic of Korea , Severity of Illness Index , Young Adult
16.
J Voice ; 33(6): 906-914, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30055985

ABSTRACT

OBJECTIVE: Although laryngeal videostroboscopy is widely utilized in the analysis of vocal fold vibrations, it is often difficult to identify patterns of vocal fold vibrations in patients with aperiodic voice signals due to failure of synchronization during laryngeal videostroboscopy examination. Therefore, the present study aimed to compare the usefulness of simultaneous two-dimensional digital kymography (2D DKG) and traditional DKG for the detection of changes in the pattern of vocal fold vibrations in patients with vocal fold scarring (VFS). METHODS: Seven patients with VFS and one normal subject underwent high-speed videoendoscopy (HSV). DKG and 2D DKG evaluations of vocal fold vibrations were performed simultaneously, following which both qualitative and quantitative analyses were performed. RESULTS: Simultaneous DKG and 2D DKG enabled observation of vibratory patterns as well as amplitude and phase symmetry. DKG revealed and provided temporal information regarding the pattern of vocal fold vibrations at sites of VFS. In contrast, 2D DKG provided real-time information regarding the pattern of vibrations for the whole vocal fold region and regions of increased stiffness, as well as spatial information regarding changes in this pattern. CONCLUSION: Our findings indicate that 2D DKG enables the assessment of overall vocal fold vibrations, regardless of periodicity, and that simultaneous DKG and 2D DKG can be used to confirm abnormal patterns of vocal fold vibrations in patients with impaired flexibility and elasticity of the vocal folds.


Subject(s)
Cicatrix/diagnosis , Dysphonia/diagnosis , Kymography , Phonation , Vocal Cords/physiopathology , Adult , Aged , Biomechanical Phenomena , Cicatrix/pathology , Cicatrix/physiopathology , Dysphonia/pathology , Dysphonia/physiopathology , Female , Humans , Laryngoscopy , Male , Middle Aged , Predictive Value of Tests , Time Factors , Vibration , Video Recording , Vocal Cords/pathology
17.
Osong Public Health Res Perspect ; 9(6): 354-361, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30584500

ABSTRACT

OBJECTIVES: The purpose of this study was to explore the effects of injection laryngoplasty (IL) with hyaluronic acid in patients with vocal fold paralysis (VFP). METHODS: A total of 50 patients with VFP participated in this study. Pre- and post-IL assessments were performed, which included analyzing the sustained vowel /a/ phonation, and the patient reading 1 Korean sentence from the "Walk" passage that comprised 25 syllables in 10 words. To investigate the effect of IL on vocal fold function, acoustic analysis (acoustic voice quality index, cepstral peak prominence, maximum phonation time, speaking fundamental frequency) was conducted and auditory-perceptual (grade and overall severity), visual judgment (gap), and self-questionnaire (voice handicap index-10) assessments were performed. RESULTS: The patients with VFP showed statistically significant differences between pre-and post-IL assessments for acoustic and auditory-perception, visual judgment, and self-questionnaire assessments. CONCLUSION: The patients with VFP showed positive change in vocal fold function between pre- and post-IL measurements. The findings showed that IL with hyaluronic acid is an effective method to improve vocal fold function in patients with VFP.

18.
Mater Sci Eng C Mater Biol Appl ; 91: 615-623, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30033294

ABSTRACT

Inflammation and thrombosis are linked to the use of polymer-based drug-eluting stents (DES). The aim of this study was to develop a polymer-free everolimus (EVL)-eluting stent using nitrogen-doped titanium dioxide (N-TiO2) and verify its efficacy by in vitro and in vivo assessment in a porcine coronary model. Various analytical approaches such as scanning electron microscopy and atomic force microscopy, electron spectroscopy, Fourier transform infrared spectrometry and contact angle measurement were employed for the characterization. As a part of biocompatibility assessment, platelet adhesion and smooth muscle cell (SMC) proliferation were examined. Bare metal stent (BMS), N-TiO2 stent, everolimus-eluting N-TiO2 (N-TiO2-EVL) stent, and commercialized EVL-eluting stent (EES) were randomly placed in forty coronary arteries in twenty pigs. After four weeks of implantation, the stents were subjected to histological and quantitative analysis. The N-TiO2 film used in this study was well coated without any cracks or peeling. Surface hydrophilicity (88.8% of angle decrement) could be associated with the decrease in surface roughness post N-TiO2 deposition (37.0%). The platelet adhesion on the N-TiO2 surfaces was less than that on the BMS surface. The proliferation of SMC was suppressed in the N-TiO2-EVL group (30.2%) but not in the BMS group. In the animal study, the percent area restenosis was significantly decreased in the N-TiO2-EVL group compared to that in the BMS group. The results (BMS; 47.0 ±â€¯11.00%, N-TiO2-EVL; 31.7 ±â€¯10.50%, and EES; 29.1 ±â€¯11.21%, n = 10, p < 0.05) were almost at par with those of the commercialized EVL-eluting stent. The introduction of N-TiO2 deposition during fabrication of polymer-free DES may be an efficient accessorial process for preventing in-stent restenosis and thrombosis.


Subject(s)
Drug-Eluting Stents , Everolimus/pharmacology , Nitrogen/chemistry , Polymers/chemistry , Titanium/chemistry , Animals , Cell Proliferation/drug effects , Coronary Restenosis/pathology , Disease Models, Animal , Myocytes, Smooth Muscle/cytology , Myocytes, Smooth Muscle/drug effects , Platelet Adhesiveness/drug effects , Platelet Aggregation/drug effects , Spectroscopy, Fourier Transform Infrared , Surface Properties , Sus scrofa , Tomography, Optical Coherence
19.
Sci Rep ; 8(1): 7383, 2018 05 09.
Article in English | MEDLINE | ID: mdl-29743620

ABSTRACT

The aim of this study was to fabricate a novel polymer-free everolimus-eluting stent with nanostructure using a femtosecond laser (FSL). The stent were coated with everolimus (EVL) using FSL and electrospinning processes. The surface was rendered hydrophobic, which negatively affected both platelet adhesion (82.1%) and smooth muscle cell response. Animal study was performed using a porcine coronary restenosis model. The study groups were divided into 1) bare metal stent (BMS), 2) poly(L-lactide) (PLA)-based EVL drug eluting stent (DES), 3) commercial EVL-eluting DES, and 4) FSL-EVL-DES. After four weeks of stent implantation, various analyses were performed. Quantitative analysis showed that the amount of in-stent restenosis was higher in the BMS group (BMS; 27.8 ± 2.68%, PLA-based DES; 12.2 ± 0.57%, commercial DES; 9.8 ± 0.28%, and FSL-DES; 9.3 ± 0.25%, n = 10, p < 0.05). Specifically, the inflammation score was reduced in the FSL-DES group (1.9 ± 0.39, n = 10, p < 0.05). The increment in re-endothelialization in the FSL-DES group was confirmed by immunofluorescence analysis. Taken together, the novel polymer-free EVL-eluting stent fabricated using FSL can be an innovative DES with reduced risk of ISR, thrombosis, and inflammation.


Subject(s)
Coronary Restenosis/surgery , Drug-Eluting Stents , Percutaneous Coronary Intervention , Animals , Coronary Restenosis/drug therapy , Coronary Restenosis/prevention & control , Everolimus/therapeutic use , Inflammation/prevention & control , Male , Swine , Thrombosis/prevention & control , Treatment Outcome
20.
J Biomater Appl ; 32(8): 1083-1089, 2018 03.
Article in English | MEDLINE | ID: mdl-29256322

ABSTRACT

The first two authors contributed equally to this study. Bioactivity and cell adhesion properties are major factors for fabricating medical devices such as coronary stents. The aim of this study was to evaluate the advantages of atmospheric-pressure plasma jet in enhancing the biocompatibility and endothelial cell-favorites. The experimental objects were divided into before and after atmospheric-pressure plasma jet treatment with the ratio of nitrogen:argon = 3:1, which is similar to air. The treated surfaces were basically characterized by means of a contact angle analyzer for the activation property on their surfaces. The effect of atmospheric-pressure plasma jet on cellular response was examined by endothelial cell adhesion and XTT analysis. It was difficult to detect any changeable morphology after atmospheric-pressure plasma jet treatment on the surface. The roughness was increased after atmospheric-pressure plasma jet treatment compared to nonatmospheric-pressure plasma jet treatment (86.781 and 7.964 nm, respectively). The X-ray photoelectron spectroscopy results showed that the surface concentration of the C-O groups increased slightly from 6% to 8% after plasma activation. The contact angle dramatically decreased in the atmospheric-pressure plasma jet treated group (22.6 ± 15.26°) compared to the nonatmospheric-pressure plasma jet treated group (72.4 ± 15.26°) ( n = 10, p < 0.05). The effect of the increment in hydrophilicity due to the atmospheric-pressure plasma jet on endothelial cell migration and proliferation was 85.2% ± 12.01% and 34.2% ± 2.68%, respectively, at 7 days, compared to the nonatmospheric-pressure plasma jet treated group (58.2% ± 11.44% in migration, n = 10, p < 0.05). Taken together, the stent surface could easily obtain a hydrophilic property by the atmospheric-pressure plasma jet method. Moreover, the atmospheric-pressure plasma jet might affect re-endothelialization after stenting.


Subject(s)
Biocompatible Materials/chemistry , Endothelial Cells/cytology , Plasma Gases/chemistry , Stents , Atmospheric Pressure , Cell Movement , Cell Proliferation , Human Umbilical Vein Endothelial Cells , Humans , Hydrophobic and Hydrophilic Interactions , Surface Properties
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