Browsing by Author "Chen, Jung-Chih"

Now showing 1 - 15 of 15

A feasibility study on non-invasive oxidative metabolism detection and acoustic assessment of human vocal cords by using optical technique
(2017-12-05)
Lin, Tzu-Chieh
;
Chen, Jung-Chih
;
Liu, Chih-Hsien
;
Lee, Chia-Yen
;
Tsou, Yung-An
Voice disorder such as vocal fatigue is a common and complex multifaceted clinical problem that presents a significant impact on quality of life. In this study, the functional near-infrared diffuse optical technique (fNIRS-DOT) was proposed as a novel approach for human vocal cords oxidative metabolism detection and acoustic assessment simultaneously to provide a multidimensional assessment of voice disorder. A totally of 60 healthy subjects included 30 male and 30 female adults of age-matched were recruited and performed a vocal loading task to trigger a mild inflammation of the vocal cords in this study. In the results of oxidative metabolism, the vocal cords expressed hypoxia after vocal loading task in both male and female groups that could provide relevant information on the relationship between tissue oxygen consumption and supply for vocal cords diagnosis. Additionally, the results of optical acoustic assessment revealed the worse/changes voice quality after vocal loading task. Therefore, integration of non-invasive oxidative metabolism detection and acoustic assessment by using optical technique could provide more relevant information for diagnosis of voice disorders. The multi-functional vocal cords detection system could provide a good feasibility for clinical applications such as diagnosis and therapeutic monitoring of voice disorder.
A Piezoceramic Sensor for Detection of Focused Ultrasound-Induced Cavitation
(2019-11-15)
Chen, Jung-Chih
;
Chang, Hsin-Yun
;
Chen, Jiun-Jung
;
Chen, Gin-Shin
;
分子醫學與生物工程研究所
Acoustic cavitation plays a key role in blood-brain-barrier opening. Stable cavitation is required for safely transient barrier disruption when inertial cavitation may cause potentially undesirable damage to brain. To ensure the safety, an appropriate passive cavitation detector is needed to monitor cavitation activity during focused ultrasound treatment. The purpose of this study was to develop a passive cavitation detector with high sensitivity at the specific frequency used in blood-brain-barrier opening. The detector was designed with the assistance of pulse-echo response simulations, using the software PiezoCAD. The active transducer of the detector was constructed of two matching layers, a PZT-5A ceramic disk and the titanium backing. The detector was characterized via the pulse-echo measurements and a commercial hydrophone was used to determine the sensitivity of the developed detector. Cavitation experiments were also performed to validate the detector. The experimental results showed that the detector had the center frequency of 1.16 MHz with the bandwidth of 44.8% and its sensitivity was 2.87 V / MPa at 1.0 MHz. In cavitation experiments, 2-MHz focused ultrasound with the focal intensity of 58 W/cm(2) and 1461 W/cm(2) induced stable cavitation and inertial cavitation in free field, separately. The spectra of the ultrasound signals detected by the detector indicated the occurrence of peak voltages at the subharmonic frequency of 1 MHz and the increase in the level of wideband signals, reflecting stable cavitation and inertial cavitation, respectively. Based on the design guideline of this study, the passive cavitation detector can be developed dedicated for blood-brain-barrier opening.
Cross-section and feasibility study on the non-invasive evaluation of muscle hemodynamic responses in Duchenne muscular dystrophy by using a near-infrared diffuse optical technique
(2018-10-01)
Weng, Wen-Chin
;
Chen, Jung-Chih
;
Lee, Chia-Yen
;
Lin, Chia-Wei
;
Lee, Wang-Tso
Duchenne muscular dystrophy (DMD) is an X-linked debilitating muscular disease that may decrease nitric oxide (NO) production and lead to functional muscular ischemia. Currently, the 6-minute walk test (6-MWT) and the North Star Ambulatory Assessment (NSAA) are the primary outcome measures in clinical trials, but they are severely limited by the subjective consciousness and mood of patients, and can only be used in older and ambulatory boys. This study proposed using functional near-infrared spectroscopy (fNIRS) to evaluate the dynamic changes in muscle hemodynamic responses (gastrocnemius and forearm muscle) during a 6-MWT and a venous occlusion test (VOT), respectively. Muscle oxygenation of the forearm was evaluated non-invasively before, during and after VOT in all participants (included 30 DMD patients and 30 age-matched healthy controls), while dynamic muscle oxygenation of gastrocnemius muscle during 6-MWT was determined in ambulatory participants (n = 18) and healthy controls (n = 30). The results reveal that impaired muscle oxygenation was observed during 6-MWT in DMD patients that may explain why the DMD patients walked shorter distances than healthy controls. Moreover, the results of VOT implied that worsening muscle function was associated with a lower supply of muscle oxygenation and may provide useful information on the relationship between muscular oxygen consumption and supply for the clinical diagnosis of DMD. Therefore, the method of fN1RS with VOT possesses great potential in future evaluations of DMD patients that implies a good feasibility for clinical application such as for monitoring disease severity of DMD. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Development of lattice-inserted 5-Fluorouracil-hydroxyapatite nanoparticles as a chemotherapeutic delivery system
(2015-10-01)
Tseng, Ching-Li
;
Chen, Jung-Chih
;
Wu, Yu-Chun
;
Fang, Hsu-Wei
;
Lin, Feng-Huei
Developing an effective vehicle for cancer treatment, hydroxyapatite nanoparticles were fabricated for drug delivery. When 5-Fluorouracil, a major chemoagent, is combined with hydroxyapatite nanocarriers by interclay insertion, the modified hydroxyapatite nanoparticles have superior lysosomal degradation profiles, which could be leveraged as controlled drug release. The decomposition of the hydroxyapatite nanocarriers facilitates the release of 5-Fluorouracil into the cytoplasm causing cell death. Hydroxyapatite nanoparticles with/without 5-Fluorouracil were synthesized and analyzed in this study. Their crystallization properties and chemical composition were examined by X-ray diffraction and Fourier transforms infrared spectroscopy. The 5-Fluorouracil release rate was determined by UV spectroscopy. The biocompatibility of hydroxyapatite-5-Fluorouracil extraction solution was assessed using 3T3 cells via a WST-8 assay. The effect of hydroxyapatite-5-Fluorouracil particles which directly work on the human lung adenocarcinoma (A549) cells was evaluated by a lactate dehydrogenase assay via contact cultivation. A 5-Fluorouracil-absorbed hydroxyapatite particles were also tested. Overall, hydroxyapatite-5-Fluorouracils were prepared using a co-precipitation method wherein 5-Fluorouracil was intercalated in the hydroxyapatite lattice as determined by X-ray diffraction. Energy dispersive scanning examination showed the 5-Fluorouracil content was higher in hydroxyapatite-5-Fluorouracil than in a prepared absorption formulation. With 5-Fluorouracil insertion in the lattice, the widths of the a and c axial constants of the hydroxyapatite crystal increased. The extraction solution of hydroxyapatite-5-Fluorouracil was nontoxic to 3T3 cells, in which 5-Fluorouracil was not released in a neutral phosphate buffer solution. In contrast, at a lower pH value (2.5), 5-Fluorouracil was released by the acidic decomposition of hydroxyapatite. Finally, the results of the lactate dehydrogenase assay revealed that 5-Fluorouracil-hydroxyapatite was highly toxic to A549 cells through direct culture, this phenomenon may result from lysosomal decomposition of particles causing 5-Fluorouracil releasing. The pH-responsive hydroxyapatite-5-Fluorouracil nanoparticles have the potential to be part of a selective drug-delivery system in chemotherapy for cancer treatment.
Dielectrophoresis System for Testing Antimicrobial Susceptibility of Gram-Negative Bacteria to beta-Lactam Antibiotics
(2017-04-18)
Su, I-Hsiu
;
Ko, Wen-Chien
;
Shih, Chung-Hsin
;
Yeh, Fang-Hao
;
Sun, Yung-Nien
Gram-negative bacteria (GNBs) are common pathogens causing severe sepsis. Rapid evaluation of drug susceptibility would guide effective antibiotic treatment and promote life-saving. A total of 78 Clinical isolates of 13 Gram-negative species collected between April 2013 and November 2013 from two medical centers in Tainan were tested. Bacterial morphology changes in different concentrations of antibiotics were observed under the electric field of a. quadruple electrode array using light microscopy. The minimal inhibitory concentrations (MICs) of four antimicrobial agents, namely, cefazolin, ceftazidime, cefepime, and doripenem, were determined by the dielectrophoretic antimicrobial susceptibility testing (dAST) and by the conventional broth dilution testing (BDT). The antibiotics at the concentration of 1x MIC induced obvious morphological changes in susceptible GNBs, including cell elongation, cell swelling, or lysis, at 90 min. In contrast, resistant strains remained unchanged. The MIC results measured by dAST were in good agreement with those of BDT (essential agreement 95.6%). The Category agreement rate was 89.2%, and the very major errors rate for dAST was 2.9%. In conclusion, dAST could accurately determine drug susceptibility within 90 min. Comprehensive tests by dAST for more drugs against more GNB species are possible in the future.
Enhancement of Neurite Outgrowth by Warming Biomaterial Ultrasound Treatment
(2020-03-01)
Chen, Jung-Chih
;
Su, Chao-Ming
;
Chen, Gin-Shin
;
Lai, Chin-Chun
;
Chen, Ching-Yun
Ultrasound is a method for enhancing neurite outgrowth because of its thermal effect. In order to reach the working temperature to enhance neurite outgrowth, long-time treatment by ultrasound is necessary, while acknowledging that the treatment poses a high risk of damaging nerve cells. To overcome this problem, we developed a method that shortens the ultrasonic treatment time with a warming biomaterial. In this study, we used Fe3O4 nanoparticle-embedded polycaprolactone (PCL) as a sonosensitized biomaterial, which has an excellent heating rate due to its high acoustic attenuation. With this material, the ultrasonic treatment time for enhancing neurite outgrowth could be effectively shortened. Ultrasonic treatment could also increase neuronal function combined with the warming biomaterial, with more promoter neuronal function than only ultrasound. Moreover, the risk of overexposure can be avoided by the use of the warming biomaterial by reducing the ultrasonic treatment time, providing better effectiveness.
Highly Sensitive Lead Ion Detection in One Drop of Human Whole Blood Using Impedance-Modulated Field-Effect Transistors and a Portable Measurement Device
(2020-06-29)
Wang, Shin-Li
;
Hsieh, Ching-Yen
;
Sukesan, Revathi
;
Chen, Jung-Chih
;
Wang, Yu-Lin
This study reports the development of a rapid heavy metal ion screening tool for whole blood samples. The test system consists of an ion selective membrane-based impedance modulated field effect transistor (FET) sensor and a portable sensor measurement unit. This study focuses on the direct detection of lead ions in whole blood, without extensive sample pre-treatments. The sensing methodology is based on impedance changes in the membrane due to the specific ionophore-target metal ion interaction in the presence of a strong electric field. The changes in impedance caused by heavy metal ions are amplified by the FET to obtain a highly sensitive lead ion detection, with very low detection limit (near 10(-11) similar to 10(-10)M Pb2+). To reduce the complexity and enhance sensor performance, the whole blood samples are fractionated on chip without any external actuation/automation using simple gravitational blood cell separation. The test results in PBS, human serum and whole blood samples demonstrate high sensitivity and wide dynamic range of lead ion detection. The miniaturized extended gate FET sensor system is ideal for point of care and home-care diagnostics for heavy metal ion in blood.
Improving the reproducibility, accuracy, and stability of an electrochemical biosensor platform for point-of-care use
(2020-05-01)
Chen, Lung-Chieh
;
Wang, Erick
;
Tai, Chun-San
;
Chiu, Yuan-Chen
;
Li, Chang-Wei
Electrochemical biosensors possess numerous desirable qualities for target detection, such as portability and ease of use, and are often considered for point-of-care (POC) development. Label-free affinity electrochemical biosensors constructed with semiconductor manufacturing technology (SMT)-produced electrodes and a streptavidin biomediator currently display the highest reproducibility, accuracy, and stability in modern biosensors. However, such biosensors still do not meet POC guidelines regarding these three characteristics. The purpose of this research was to resolve the limitations in reproducibility and accuracy caused by problems with production of the biosensors, with the aim of developing a platform capable of producing devices that exceed POC standards. SMT production settings were optimized and bioreceptor immobilization was improved through the use of a unique linker, producing a biosensor with exceptional reproducibility, impressive accuracy, and high stability. Importantly, the three characteristics of the sensors produced using the proposed platform all meet POC standards set by the Clinical and Laboratory Standards Institute (CLSI). This suggests possible approval of the biosensors for POC development. Furthermore, the detection range of the platform was demonstrated by constructing biosensors capable of detecting common POC targets, including circulating tumor cells (CTCs), DNA/RNA, and curcumin, and the devices were optimized for POC use. Overall, the platform developed in this study shows high potential for production of POC biosensors.
Label-Free Impedimetric Immunosensors Modulated by Protein A/Bovine Serum Albumin Layer for Ultrasensitive Detection of Salbutamol
(2020-02-01)
Lin, Chia-Hung
;
Lin, Ming-Jie
;
Huang, Jie-De
;
Chuang, Yu-Sheng
;
Kuo, Yu-Fen
The sensing properties of immunosensors are determined not only by the amount of immobilized antibodies but also by the number of effective antigen-binding sites of the immobilized antibody. Protein A (PA) exhibits a high degree of affinity with the Fc part of IgG antibody to feasibly produce oriented antibody immobilization. This work proposes a simple method to control the PA surface density on gold nanostructure (AuNS)-deposited screen-printed carbon electrodes (SPCEs) by mixing concentration-varied PA and bovine serum albumin (BSA), and to explore the effect of PA density on the affinity attachment of anti-salbutamol (SAL) antibodies by electrochemical impedance spectroscopy. A concentration of 100 mu g/mL PA and 100 mu g/mL BSA can obtain a saturated coverage on the 3-mercaptoproponic acid (MPA)/AuNS/SPCEs and exhibit a 50% PA density to adsorb the amount of anti-SAL, more than other concentration-varied PA/BSA-modified electrodes. Compared with the randomly immobilized anti-SAL/MPA/AuNS/SPCEs and the anti-SAL/PA(100 mu g/mL):BSA(0 mu g/mL)/MPA/AuNS/SPCE, the anti-SAL/PA(100 mu g/mL): BSA(100 mu g/mL)/MPA/AuNS/SPCE-based immunosensors have better sensing properties for SAL detection, with an extremely low detection limit of 0.2 fg/mL and high reproducibility (<2.5% relative standard deviation). The mixture of PA(100 mu g/mL):BSA(100 mu g/mL) for the modification of AuNS/SPCEs has great promise for forming an optimal protein layer for the oriented adsorption of IgG antibodies to construct ultrasensitive SAL immunosensors.
Monitoring of Retinoic Acid Uptake into H9c2 Cells Using Electric-Double-Layer (EDL) Gated Field-Effect Transistors
(2020-08-24)
Tsai, Shu-Yi
;
Wang, Jen-Hsuan
;
Chen, Po-Hsuan
;
Paulose, Akhil K.
;
Wang, Yu-Lin
Fibronectin-immobilized extended gated electric-double-layer field-effect transistors are demonstrated for non-invasively monitoring retinoic acid uptake by H2c9 cell lines. The diffusion of retinoic acid into the cells is electrically measured as the drain current gain based on the change of the voltage drop in culture medium produced by the capacitance change of the cells. Impedance measurement and analysis reveal that the imaginary part dominates the major voltage drop in medium and the sensing characteristics as well. The sensor chip is confirmed to be a capacitive equivalent model and combining with the signal amplification by FETs. This non-invasive cell-based sensor platform enables to monitor the interaction between molecules and cells, which is promising for prospective applications in all kinds of intracellular study and drug screening.
Progress in Polymeric Nano-Medicines for Theranostic Cancer Treatment
(2020-03-01)
Ali, Imran
;
Alsehli, Mosa
;
Scotti, Luciana
;
Scotti, Marcus Tullius
;
Tsai, Shang-Ting
Cancer is a life-threatening disease killing millions of people globally. Among various medical treatments, nano-medicines are gaining importance continuously. Many nanocarriers have been developed for treatment, but polymerically-based ones are acquiring importance due to their targeting capabilities, biodegradability, biocompatibility, capacity for drug loading and long blood circulation time. The present article describes progress in polymeric nano-medicines for theranostic cancer treatment, which includes cancer diagnosis and treatment in a single dosage form. The article covers the applications of natural and synthetic polymers in cancer diagnosis and treatment. Efforts were also made to discuss the merits and demerits of such polymers; the status of approved nano-medicines; and future perspectives.
Rapid and Highly Sensitive Extended Gate FET-Based Sensors for Arsenite Detection Using a Handheld Device
(2020-01-12)
Tatavarthi, Sai Sudheer
;
Wang, Shin-Li
;
Wang, Yu-Lin
;
Chen, Jung-Chih
;
分子醫學與生物工程研究所
Heavy metals are very harmful to the environment and is toxic which affects the human health. Monitoring the heavy metal ion in food and water is necessary. In this research, we developed a FET based ion selective sensor for detecting Arsenite (As(III)) ions by a hand held device. The sensor characteristics are carried out and illustrated. This selective sensor shows higher sensitivity (35.19 mV/log [As3+]) than the ideal Nernstian slope. The dynamic range of the Arsenite based ion sensor is from 10(-10)M to 10(-4)M. The detection limit of this FET based ion selective sensor is below 10(-10)M and is comparable to ICP-MS. The sensor captures the particular target ion and is not affected by the interfering ions such as Cadmium and Lead. The sensitivity and selectivity characteristics are comparatively better than the traditional potentiometric Ion selective electrode (ISE). The sensor has shorter response time and is easy to operate. This sensor is affordable for everyone and convenient to use for monitoring the food and drinking water frequently.
Study of in vitro Diagnostic Preconcentration Technique via Surface Acoustic Wave Modified With the 54 MHz Communication Chip
(2018-01-01)
Chien, Ming-Hung
;
Chiang, S. H.
;
Chuang, Ching-Cheng
;
Chen, Jung-Chih
;
分子醫學與生物工程研究所
Particle separation and specimen preconcentration techniques are ones of the essential but time-consuming steps in the beginning of many biomedical sensing experiments or biosensor design. Hence, the study demonstrates a simple microfluidic system combined with surface acoustic wave (SAW) device, hoping to help researchers could spend less time on this routine process. A detachable and reusable acrylic microchannel is placed on the customized SAW chip which releases a 54 MHz SAW wave to separate 10 mu m particles from the others (1 mu m & 6 mu m) under the cut-off input power 23.4 dBm verified in the study and about 90% separation efficiency in average.
The Effects of Different Dynamic Culture Systems on Cell Proliferation and Osteogenic Differentiation in Human Mesenchymal Stem Cells
(2019-08-02)
Tsai, Hsiou-Hsin
;
Yang, Kai-Chiang
;
Wu, Meng-Huang
;
Chen, Jung-Chih
;
Tseng, Ching-Li
The culture environment plays an important role for stem cells' cultivation. Static or dynamic culture preserve differential potentials to affect human mesenchymal stem cells' (hMSCs) proliferation and differentiation. In this study, hMSCs were seeded on fiber disks and cultured in a bidirectional-flow bioreactor or spinner-flask bioreactor with a supplement of osteogenic medium. The hMSCs' proliferation, osteogenic differentiation, and extracellular matrix deposition of mineralization were demonstrated. The results showed that the spinner flask improved cell viability at the first two weeks while the bidirectional-flow reactor increased the cell proliferation of hMSCs through the four-week culture period. Despite the flow reactor having a higher cell number, a lower lactose/glucose ratio was noted, revealing that the bidirectional-flow bioreactor provides better oxygen accessibility to the cultured cells/disk construct. The changes of calcium ions in the medium, the depositions of Ca2+ in the cells/disk constructs, and alkaline phosphate/osteocalcin activities showed the static culture of hMSCs caused cells to mineralize faster than the other two bioreactors but without cell proliferation. Otherwise, cells were distributed uniformly with abundant extracellular matrix productions using the flow reactor. This reveals that the static and dynamic cultivations regulated the osteogenic process differently in hMSCs. The bidirectional-flow bioreactor can be used in the mass production and cultivation of hMSCs for applications in bone regenerative medicine.
The photothermal effect of silica-carbon hollow sphere-concanavalin A on liver cancer cells
(2015-01-01)
Chen, Ying-Chi
;
Chiu, Wen-Tai
;
Chen, Jung-Chih
;
Chang, Chia-Sheng
;
Wang, Lily Hui-Ching
Hepatocellular carcinoma (HCC) is one of the most common cancers and causes of death by cancer. Concanavalin A (ConA) lectin can specifically bind to the glycoprotein receptors of HCC, which are produced by the aberrant overexpression of liver cancer cells. ConA was used in the current study to conjugate on silica-carbon hollow spheres (SCHSs) and applied in the thermal ablation therapy of liver cancer cell lines under near-infrared (NIR) laser irradiation. We found that the amount of ConA-SCHS complex binding to hepatoma cells was significantly higher than that seen with normal hepatocytes, based on flow cytometric analysis and confocal imaging. Hepatoma cells incubated with ConA-SCHSs were thus more easily killed by the subsequent irradiation with a NIR laser. The results show that the ConA-SCHS complex may enhance the interaction with highly expressed ConA receptors on hepatoma cells, and thus serve as an effective photothermal therapy agent for liver cancer treatment.