ENERGY TRANSDUCTION IN MOLECULAR MACHINES

CHENG-HUNG CHANG,TIAN YOW TSONG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2007 NANO Vol.2 No.5

An applied force may cause the conformation and thus, the activity of a biological molecule to change. Here we consider a system in which an oscillating or fluctuating electric field is used to actuate membrane protein activities. Most proteins have electric dipoles and net charges in the structure and their conformations are susceptible to the electric and magnetic perturbation. The shape of a cell may also amplify an electric field across its plasma membrane. Therefore, a membrane integral protein such as an ion channel, an ion pump, or a molecular motor, is especially amenable to electric perturbation. The theory of electroconformational coupling addresses the functional implication of this field effect. When an alternating electric field or a fluctuating electric field is employed to actuate a two-state protein oscillator, the dynamics of the conformational change of the protein can be synchronized with the applied field. Through this two-state protein oscillator, we construct a four-state catalytic wheel by coupling an energy transducer mechanism to the two-state protein oscillator. Analysis shows that the catalytic wheel can extract energy from a disordered external energy source, be it electrical, mechanical, or chemical, and convert this stochastic energy source to a usable energy format. The catalytic wheel is tested with the experimental data on the electric field-stimulated cation pumping of Na, K-ATPase. A dipole ratchet model based on the electroconformational coupling concept will also be discussed and compared with the ATP-dependent rotation of a rotary motor F1-ATPase. Since the working principle of this model is simpler than that of F1-ATPase, it provides an easier way to realize a nanoscale rotary motor than artificially reconstructing a F1-ATPase.

A Single-Stage LED Tube Lamp Driver with Input-Current Shaping for Energy-Efficient Indoor Lighting Applications

Cheng, Chun-An,Chang, Chien-Hsuan,Cheng, Hung-Liang,Chung, Tsung-Yuan,Tseng, Ching-Hsien,Tseng, Kuo-Ching The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

This study proposes a single-stage light-emitting diode (LED) tube lamp driver with input-current shaping for T8/T10-type fluorescent lamp replacements. The proposed AC-DC LED driver integrates a dual-boost converter with coupled inductors and a half-bridge series-resonant converter with a bridge rectifier into a single-stage power conversion topology. This paper presents the operational principles and design considerations for one T8-type 18 W-rated LED tube lamp with line input voltages ranging from 100 V rms to 120 V rms. Experimental results for the prototype driver show that the highest power factor (PF = 0.988), lowest input current total harmonic distortion (THD = 7.22%), and highest circuit efficiency (η = 92.42%) are obtained at an input voltage of 120 V. Hence, the proposed driver is feasible for use in energy-efficient indoor lighting applications.

Prognostic Factors in Adult Patients with Solid Cancers and Bone Marrow Metastases

Hung, Yu-Shin,Chou, Wen-Chi,Chen, Tai-Di,Chen, Tse-Ching,Wang, Po-Nan,Chang, Hung,Hsu, Hung-Chih,Shen, Wen-Chi,Cheng, Wei-Hong,Chen, Jen-Shi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Background: Solid cancers with bone marrow metastases are rare but lethal. This study aimed to identify clinical factors predictive of survival in adult patients with solid cancers and bone marrow metastases. Methods: A total of 83 patients were enrolled consecutively between January 1, 2000 and December 31, 2012. Bone marrow metastases were confirmed by biopsies. Patient clinical features and laboratory data were analyzed for associations. Results: The median age of the patients was 54 years (range, 23-88 years), and 58% were male. The 3 most common primary tumor locations were the stomach (32 patients, 39%), prostate (16 patients, 19%), and lungs (12 patients, 15%). The median overall survival was 49 days (range, 3-1423 days). Patients with Eastern Cooperative Oncology Group performance status 1, cancers of prostate origin, platelet counts over 50,000/ml, and undergoing antitumor therapies had a significantly better prognosis in the multivariate analysis. The median survival times were 173 and 33 days for patients with 2-3 more favorable parameters (n=24) and those with 0-1 (n=69), respectively (hazard ratio 0.30; 95% CI 0.17-0.52, p<0.001). Conclusions: Solid cancers with bone marrow metastases are dismal and incurable diseases. Understanding prognostic factors to these diseases helps medical personnel to provide appropriate treatments and better inform patients about outcomes. Antitumor therapies may improve outcomes in selected patient cohorts.

An update of preimplantation genetic diagnosis in gene diseases, chromosomal translocation, and aneuploidy screening

Chang, Li-Jung,Chen, Shee-Uan,Tsai, Yi-Yi,Hung, Chia-Cheng,Fang, Mei-Ya,Su, Yi-Ning,Yang, Yu-Shih The Korean Society for Reproductive Medicine 2011 Clinical and Experimental Reproductive Medicine Vol.38 No.3

Preimplantation genetic diagnosis (PGD) is gradually widely used in prevention of gene diseases and chromosomal abnormalities. Much improvement has been achieved in biopsy technique and molecular diagnosis. Blastocyst biopsy can increase diagnostic accuracy and reduce allele dropout. It is cost-effective and currently plays an important role. Whole genome amplification permits subsequent individual detection of multiple gene loci and screening all 23 pairs of chromosomes. For PGD of chromosomal translocation, fluorescence $in-situ$ hybridization (FISH) is traditionally used, but with technical difficulty. Array comparative genomic hybridization (CGH) can detect translocation and 23 pairs of chromosomes that may replace FISH. Single nucleotide polymorphisms array with haplotyping can further distinguish between normal chromosomes and balanced translocation. PGD may shorten time to conceive and reduce miscarriage for patients with chromosomal translocation. PGD has a potential value for mitochondrial diseases. Preimplantation genetic haplotyping has been applied for unknown mutation sites of single gene disease. Preimplantation genetic screening (PGS) using limited FISH probes in the cleavage-stage embryo did not increase live birth rates for patients with advanced maternal age, unexplained recurrent abortions, and repeated implantation failure. Polar body and blastocyst biopsy may circumvent the problem of mosaicism. PGS using blastocyst biopsy and array CGH is encouraging and merit further studies. Cryopreservation of biopsied blastocysts instead of fresh transfer permits sufficient time for transportation and genetic analysis. Cryopreservation of embryos may avoid ovarian hyperstimulation syndrome and possible suboptimal endometrium.

On-site Visual Construction Management System Based on the Integration of SLAM-based AR and BIM on a Handheld Device

Chang-Cheng Hsieh,Hung-Ming Chen,Sheng-Kai Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.11

Recently, Simultaneous Localization and Mapping (SLAM) has been integrated into the development of AR systems. Using conventional SLAM adoption method to overlay a building information model (BIM) onto the image of a real scene on handheld device in a construction site will result in poor model overlaying accuracy owing to the relatively unique environment and monotonous texture of such environment. This paper proposes an adoption method of SLAM suitable for construction environment to improve positioning accuracy for the fitting of BIMs for the AR presentation. In addition, a AR system to visualize construction progress on-site is developed. It allows site personnel to input on-site work progress through an AR device, then compares the originally planned construction progress with the actual on-site progress, and presents BIM components using different colors in the AR mode to show whether work progress on each component is ahead or behind schedule intuitively.

Impact of Clinical Characteristics of Individual Metabolic Syndrome on the Severity of Insulin Resistance in Chinese Adults

Chang-Hsun Hsieh,Yi-Jen Hung,Du-An Wu,Shi-Wen Kuo,Chien-Hsing Lee,Wayne Huey-Herng Sheu,Jer-Chuan Li,Kuan-Hung Yeh,Cheng-Yu Chen,Dee Pei 대한의학회 2007 Journal of Korean medical science Vol.22 No.1

Contrasting clinical characteristics and treatment patterns in women with newly diagnosed advanced-stage epithelial ovarian cancer in Australia, South Korea and Taiwan

Hung-Hsueh Chou,Sian Fereday,Anna DeFazio,Chih-Long Chang,David Bowtell,Heng-Cheng Hsu,Nadia Traficante,Soo Young Jeong,Wen-Fang Cheng,Dinuka Ariyarantne,Australian Ovarian Cancer Study Group,Teresa T 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.1

Objective: The real-world INFORM study analyzed sociodemographics, treatment patterns and clinical outcomes for patients with newly diagnosed advanced epithelial ovarian cancer (EOC) in Australia, South Korea (S.Korea) and Taiwan preceding incorporation of poly(ADP-ribose) polymerase inhibitors into clinical practice. Methods: Retrospective data from patients diagnosed with EOC (high-grade serous EOC for Taiwan) between January 2014 and December 2018 with ≥12 months follow-up from diagnosis were analyzed descriptively. Survival was evaluated by Kaplan-Meier with two-sided 95% confidence interval (CI). Results: Of the 987 patients (Australia, 223; S.Korea, 513; Taiwan, 251), 98% received platinum-based chemotherapy (CT). In S.Korea and Taiwan 76.0% and 78.9% respectively underwent primary cytoreductive surgery; in Australia, 56.5% had interval debulking surgery. Bevacizumab was included in primary/maintenance therapy for 22.4%, 14.6% and 6.8% of patients in Australia, S.Korea and Taiwan, respectively. Patients receiving bevacizumab were high-risk (reimbursement policy) and achieved similar real-world progression-free survival (PFS) compared with CT only. Overall, the median real-world PFS (months; 95% CI) was similar across Australia (16.0 [14.63–18.08]), S.Korea (17.7 [16.18–19.27]) and Taiwan (19.1 [17.56–22.29]). Conclusion: This study reveals poor prognosis despite differences in demographics and treatment patterns for patients with EOC across Asia-Pacific suggesting the need for biomarker-driven novel therapies to improve outcomes.

The feasibility of detecting endometrial and ovarian cancer using DNA methylation biomarkers in cervical scrapings

Cheng-Chang Chang,Hui-Chen Wang,Yu-Ping Liao,Yu-Chih Chen,Yu-Chun Weng,Mu-Hsien Yu,Hung-Cheng Lai 대한부인종양학회 2018 Journal of Gynecologic Oncology Vol.29 No.1

Objective: We hypothesized that DNA methylation of development-related genes may occur in endometrial cancer (EC)/ovarian cancer (OC) and may be detected in cervical scrapings. Methods: We tested methylation status by quantitative methylation-specific polymerase chain reaction for 14 genes in DNA pools of endometrial and OC tissues. Tissues of EC/normal endometrium, OC/normal ovary, were verified in training set using cervical scrapings of 10 EC/10 OC patients and 10 controls, and further validated in the testing set using independent cervical scrapings in 30 EC/30 OC patients and 30 controls. We generated cutoff values of methylation index (M-index) from cervical scrapings to distinguish between cancer patients and control. Sensitivity/specificity of DNA methylation biomarkers in detecting EC and OC was calculated. Results: Of 14 genes, 4 (PTGDR, HS3ST2, POU4F3, MAGI2) showed hypermethylation in EC and OC tissues, and were verified in training set. POU4F3 and MAGI2 exhibited hypermethylation in training set were validated in independent cases. The mean M-index of POU4F3 is 78.28 in EC and 20.36 in OC, which are higher than that in controls (6.59; p<0.001 and p=0.100, respectively), and that of MAGI2 is 246.0 in EC and 12.2 in OC, which is significantly higher that than in controls (2.85; p<0.001 and p=0.480, respectively). Sensitivity and specificity of POU4F3/MAGI2 were 83%–90% and 69%–75% for detection of EC, and 61% and 62%–69% for the detection of OC. Conclusion: The findings demonstrate the potential of EC/OC detection through testing for DNA methylation in cervical scrapings.

Characterization of the dynamic behavior of a linear guideway mechanism

Chang, Jyh-Cheng,Wu, Shih-Shyn James,Hung, Jui-Pin Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.25 No.1

Dynamic behaviors of the contact surface between ball and raceway in a guideway mechanism vary with the applied loads and hence affect the mechanical responses of machine tools. The study aims to investigate the nonlinear characteristics of dynamic behaviors at the rolling contact interface in linear guideway mechanisms. Firstly, analytical method was introduced to understand the contact behaviors based on Hertz contact theory in a point-to-point way. Then, the finite element approach with a three-dimensional surface-to-surface contact model and appropriate contact stiffness was developed to study the dynamic characteristics of such linear guideways. Finally, experiments with modal test were conducted to verify the significance of both the analytical and the numerical results. Results told that the finite element approach may provide significant predictions. The study results also concluded that the current nonlinear models based on Hertz's contact theory may accurately describe the contact characteristic of a linear guideway mechanism. In the modal analysis, it was told that the natural frequencies vary a little with different loading conditions; however, the mode shapes are changed obviously with the magnitude of applied loads. Therefore, the stiffness of contact interface needs to be properly adjusted during simulation which may affect the dynamic characteristics of the machine tools.

Changes in prostate-specific antigen kinetics during androgen-deprivation therapy as a predictor of response to abiraterone in chemonaïve patients with metastatic castration-resistant prostate cancer

Chung-Lin Lee,Ying-Hsu Chang,Chung-Yi Liu,Ming-Li Hsieh,Liang-Kang Huang,Yuan-Cheng Chu,Hung-Cheng Kan,Po-Hung Lin,Kai-Jie Yu,Cheng-Keng Chuang,Chun-Te Wu,See-Tong Pang,I-Hung Shao 대한비뇨의학회 2022 Investigative and Clinical Urology Vol.63 No.5

Purpose: Metastatic castration-resistant prostate cancer (mCRPC) has a poor prognosis. Abiraterone acetate (AA), enzalutamide, and chemotherapy are first-line treatments for patients with mCRPC. This study examined prognostic factors for AA response in the form of prostate-specific antigen (PSA) kinetics throughout androgen-deprivation therapy (ADT) in chemonaïve patients with mCRPC. Materials and Methods: We retrospectively included data from 34 chemonaïve patients with mCRPC who had received AA at some point between January 2017 and December 2018. We separated patients into two study arms according to the decrease in PSA percentages after use of AA for 3 months. We correlated PSA kinetics parameters with response and compared the two study groups with respect to PSA kinetics. Results: The patients’ median age was 77 years. In the total group of patients, 64% had a response to AA, whereas 35% did not. The ratio of the PSA level at nadir to the level during ADT was significantly higher in the AA-sensitive group (19.78 vs. 1.03, p=0.019). Conclusions: Patients who experienced a dramatic change in PSA level during ADT were more likely to be resistant to AA after progression to mCRPC. Chemotherapy rather than AA might be more suitable as a first-line treatment for these patients.