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Wang WH, Lin CY, Chang K, Urbina AN, Assavalapsakul W, Thitithanyanont A, Lu PL, Chen YH, Wang SF. A clinical and epidemiological survey of the largest dengue outbreak in Southern Taiwan in 2015. Int J Infect Dis 2019; 88:88-99. [PMID: 31521850 DOI: 10.1016/j.ijid.2019.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/24/2019] [Accepted: 09/09/2019] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVES This study examined the epidemiological, clinical, and immunological characteristics of the 2015 dengue outbreak in Taiwan. METHODS Clinical data were collected from dengue fever (DF) and dengue hemorrhagic fever (DHF) patients. A phylogenetic tree was used to analyze the source of the outbreak strain. Paired plasma samples from DF/DHF patients were used for antibody-dependent enhancement (ADE) assay and cytokine multiplex biometric immunoassay to validate the immunological mechanism. RESULTS This outbreak mainly occurred in two of the southern cities of Taiwan: Tainan (n=22 777; 52%) and Kaohsiung (n=19 784; 45%). A high DHF death rate was noted (34.6%). The case (DHF) and control (DF) study indicated that older age (>60 years), type II diabetes, and hypertension were risk factors correlated with the development of DHF (p< 0.0001). The phylogenetic tree results suggested that the outbreak-associated strain was dengue virus serotype 2 and cosmopolitan genotype, forming a stable cluster with the isolates from Thailand and Indonesia (bootstrap value of 99%). Cytokine analyses demonstrated that levels of interleukin (IL)-6, IL-4, IL-13, IL-1β, interferon gamma (IFN-γ), and granulocyte-macrophage colony-stimulating factor (GM-CSF) were significantly higher in DHF patients compared to DF patients (p< 0.001). The ADE assay showed that diluted plasma containing preexisting dengue antibodies from DHF patients significantly enhanced dengue infection (p< 0.05). CONCLUSION The results suggest that older age, type II diabetes, hypertension, immunological cytokine dysregulation, and preexisting dengue antibodies inducing ADE infection are correlated with dengue severity. This study also indicates that the largest dengue outbreak in Taiwan might have been a result of imported DF from dengue epidemic regions.
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Tan S, Chang K, Chin S, Kadir SSA, Cheong S, Then K, Ho K, Cheng Z, Then K. Cytopeutics® umbilical cord mesenchymal stromal cells (Cyto-MSC) for patients with grade II–IV acute graft-versus-host disease: a phase I/II clinical study – protocol overview. Cytotherapy 2019. [DOI: 10.1016/j.jcyt.2019.03.520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Smith MS, Cash B, Konda V, Trindade AJ, Gordon S, DeMeester S, Joshi V, Diehl D, Ganguly E, Mashimo H, Singh S, Jobe B, McKinley M, Wallace M, Komatsu Y, Thakkar S, Schnoll-Sussman F, Sharaiha R, Kahaleh M, Tarnasky P, Wolfsen H, Hawes R, Lipham J, Khara H, Pleskow D, Navaneethan U, Kedia P, Hasan M, Sethi A, Samarasena J, Siddiqui UD, Gress F, Rodriguez R, Lee C, Gonda T, Waxman I, Hyder S, Poneros J, Sharzehi K, Di Palma JA, Sejpal DV, Oh D, Hagen J, Rothstein R, Sawhney M, Berzin T, Malik Z, Chang K. Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry. Dis Esophagus 2019; 32:5481776. [PMID: 31037293 PMCID: PMC6853704 DOI: 10.1093/dote/doz029] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/08/2019] [Indexed: 12/11/2022]
Abstract
Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291.
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Friedstat JS, Stockley O, Chang K, Levin J, Sangji N, Sheridan R, Schulz JT, Kasis L, Ryan CM, Goverman J, Schneider JC. 310 Evaluation of Patient Reported Outcomes Before and After Burn Reconstruction. J Burn Care Res 2019. [DOI: 10.1093/jbcr/irz013.224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Newton PN, Keolouangkhot V, Lee SJ, Choumlivong K, Sisouphone S, Choumlivong K, Vongsouvath M, Mayxay M, Chansamouth V, Davong V, Phommasone K, Sirisouk J, Blacksell SD, Nawtaisong P, Moore CE, Castonguay-Vanier J, Dittrich S, Rattanavong S, Chang K, Darasavath C, Rattanavong O, Paris DH, Phetsouvanh R. A Prospective, Open-label, Randomized Trial of Doxycycline Versus Azithromycin for the Treatment of Uncomplicated Murine Typhus. Clin Infect Dis 2019; 68:738-747. [PMID: 30020447 PMCID: PMC6376095 DOI: 10.1093/cid/ciy563] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 07/07/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Murine typhus, or infection with Rickettsia typhi, is a global but neglected disease without randomized clinical trials to guide antibiotic therapy. METHODS A prospective, open, randomized trial was conducted in nonpregnant, consenting inpatient adults with rapid diagnostic test evidence of uncomplicated murine typhus at 2 hospitals in Vientiane, Laos. Patients were randomized to 7 days (D7) or 3 days (D3) of oral doxycycline or 3 days of oral azithromycin (A3). Primary outcome measures were fever clearance time and frequencies of treatment failure and relapse. RESULTS Between 2004 and 2009, the study enrolled 216 patients (72 per arm); 158 (73.2%) had serology/polymerase chain reaction (PCR)-confirmed murine typhus, and 52 (24.1%) were R. typhi PCR positive. The risk of treatment failure was greater for regimen A3 (22.5%; 16 of 71 patients) than for D3 (4.2%; 3 of 71) or D7 (1.4%; 1 of 71) (P < .001). Among R. typhi PCR-positive patients, the area under the time-temperature curve and the fever clearance time were significantly higher for A3 than for D3 (1.8- and 1.9-fold higher, respectively; P = .005) and D7 (1.5- and 1.6-fold higher; P = .02). No patients returned with PCR-confirmed R. typhi relapse. CONCLUSION In Lao adults, azithromycin is inferior to doxycycline as oral therapy for uncomplicated murine typhus. For doxycycline, 3- and 7-day regimens have similar efficacy. Azithromycin use in murine typhus should be reconsidered. Investigation of genomic and phenotypic markers of R. typhi azithromycin resistance is needed. CLINICAL TRIAL REGISTRATION ISRCTN47812566.
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Chang K, Willis JA, Reumers J, Taggart MW, San Lucas FA, Thirumurthi S, Kanth P, Delker DA, Hagedorn CH, Lynch PM, Ellis LM, Hawk ET, Scheet PA, Kopetz S, Arts J, Guinney J, Dienstmann R, Vilar E. Colorectal premalignancy is associated with consensus molecular subtypes 1 and 2. Ann Oncol 2018; 29:2061-2067. [PMID: 30412224 PMCID: PMC6225810 DOI: 10.1093/annonc/mdy337] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background Gene expression-based profiling of colorectal cancer (CRC) can be used to identify four molecularly homogeneous consensus molecular subtype (CMS) groups with unique biologic features. However, its applicability to colorectal premalignant lesions remains unknown. Patients and methods We assembled the largest transcriptomic premalignancy dataset by integrating different public and proprietary cohorts of adenomatous and serrated polyps from sporadic (N = 311) and hereditary (N = 78) patient populations and carried out a comprehensive analysis of carcinogenesis pathways using the CMS random forest (RF) classifier. Results Overall, transcriptomic subtyping of sporadic and hereditary polyps revealed CMS2 and CMS1 subgroups as the predominant molecular subtypes in premalignancy. Pathway enrichment analysis showed that adenomatous polyps from sporadic or hereditary cases (including Lynch syndrome) displayed a CMS2-like phenotype with WNT and MYC activation, whereas hyperplastic and serrated polyps with CMS1-like phenotype harbored prominent immune activation. Rare adenomas with CMS4-like phenotype showed significant enrichment for stromal signatures along with transforming growth factor-β activation. There was a strong association of CMS1-like polyps with serrated pathology, right-sided anatomic location and BRAF mutations. Conclusions Based on our observations made in premalignancy, we propose a model of pathway activation associated with CMS classification in colorectal carcinogenesis. Specifically, while adenomatous polyps are largely CMS2, most hyperplastic and serrated polyps are CMS1 and may transition into other CMS groups during evolution into carcinomas. Our findings shed light on the transcriptional landscape of premalignant colonic polyps and may help guide the development of future biomarkers or preventive treatments for CRC.
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Chang HL, Chen PL, Lin SY, Chen TC, Chang K, Ko WC, Lu PL, Chen YH. Two fatal cases of Aeromonas dhakensis bacteremia and necrotizing fasciitis in severe dengue patients. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2018; 51:692-694. [DOI: 10.1016/j.jmii.2018.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 03/14/2018] [Accepted: 03/15/2018] [Indexed: 12/14/2022]
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Chen CY, Hsieh PH, Chang CY, Yang ST, Chen YH, Chang K, Lu PL. Molecular epidemiology of the emerging ceftriaxone resistant non-typhoidal Salmonella in southern Taiwan. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2018; 52:289-296. [PMID: 30201133 DOI: 10.1016/j.jmii.2018.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 08/08/2018] [Accepted: 08/15/2018] [Indexed: 11/25/2022]
Abstract
BACKGROUND/PURPOSE The increasing trend of ceftriaxone resistant non-typhoidal Salmonella (NTS) worldwide is of serious concern, however, data is lacked in southern Taiwan. METHODS Salmonella isolates were collected at a regional hospital in Kaohsiung during 2004-2013. Ceftriaxone resistant NTS isolates were further characterized for beta-lactamases, typed by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and their plasmids were analyzed by PCR replicon typing and plasmid mutilocus sequence typing. RESULTS Among 528 NTS isolates, the most common serogroup is serogroup B (44.9%), followed by serogroup D, and serogroup C. Eleven (2.1%) isolates were resistant to ceftriaxone and were distributed in three peak periods (2010, 2011, and 2013). PFGE and MLST revealed the ten serogroup B isolates were of two clones. Beta-lactamase genes were detected in 10 of the 11 isolates, including CMY-2 (5 isolates), TEM-1 (2), CTX-M-14 (1), and 2 isolates carried both TEM-1 and CMY-2. Plasmid incompatibility types were identified in 9 (81.8%) isolates; three were IncI1, three was IncHI2, one was IncFIB and two had both replicons of IncI1 and IncHI2. The only ESBL gene blaCTM-X-14 was found in an isolate with plasmid belonged to IncHI2, which has not been reported in NTS in Taiwan before. Most MLST types and plasmid MLST types of NTS isolates in this study are different from those in northern Taiwan. CONCLUSION Though clonal spread of ceftriaxone resistant NTS was suggested by PFGE and MLST, plasmid characterization and beta-lactamase detection revealed their plasmid types and beta-lactamase types were different.
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Lee K, Hwang B, Chang K. Controlling risk factors at target levels affects coronary ct angiographic findings and cardiovascular events in asymptomatic patients with type 2 diabetes. Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.06.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kim T, Chang K, Kang K, Kim C, Kim E, Park H, Park E, Kim J, Lee E, Kim I, Seong E. MIR299, 145, and 494 regulate human aortic smooth muscle cell aging via direct targeting of VEZF1. Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.06.351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Brown DJ, Hickey S, Levin J, Chang K, Sheridan R, Ryan C, Friedstat J, Schulz J, Goverman J. 532 The Use of Topical Steroids for the Treatment of Burn-Related Hypertrophic Granulation Tissue and Unstable Scar. J Burn Care Res 2018. [DOI: 10.1093/jbcr/iry006.455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Zopes J, Sasaki K, Cujia KS, Boss JM, Chang K, Segawa TF, Itoh KM, Degen CL. High-Resolution Quantum Sensing with Shaped Control Pulses. PHYSICAL REVIEW LETTERS 2017; 119:260501. [PMID: 29328731 DOI: 10.1103/physrevlett.119.260501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Indexed: 06/07/2023]
Abstract
We investigate the application of amplitude-shaped control pulses for enhancing the time and frequency resolution of multipulse quantum sensing sequences. Using the electronic spin of a single nitrogen-vacancy center in diamond and up to 10 000 coherent microwave pulses with a cosine square envelope, we demonstrate 0.6-ps timing resolution for the interpulse delay. This represents a refinement by over 3 orders of magnitude compared to the 2-ns hardware sampling. We apply the method for the detection of external ac magnetic fields and nuclear magnetic resonance signals of ^{13}C spins with high spectral resolution. Our method is simple to implement and especially useful for quantum applications that require fast phase gates, many control pulses, and high fidelity.
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Chang K, Lee JT, Vamos E, Palladino R, Soljak M, Majeed A, Millett C. Socio-demographic inequalities in the effectiveness of England’s NHS Health Check. Eur J Public Health 2017. [DOI: 10.1093/eurpub/ckx187.428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Chang K, Xia S, Sun YG, Xin JF, Shen WB. [Liposuction combined with lymphatico-venous anastomosis for treatment of secondary lymphedema of the lower limbs: a report of 49 cases]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2017; 55:274-278. [PMID: 28355765 DOI: 10.3760/cma.j.issn.0529-5815.2017.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To study the clinical effects of liposuction combined with lymphatico-venous anastomosis for treatment of secondary lymphedema of the lower limbs. Methods: A retrospective analysis was performed for 49 patients who had undergone liposuction combined with lymphatico-venous anastomosis to treat secondary lymphedema of the lower limbs at Department of Lymph Surgery, Beijing Shijitan Hospital from November 2013 to February 2015.All patients were female aging from 31 to 70 years with median age of (52±10)years.All patients had history of pelvic surgery.There were 32 cases with cervical carcinoma, 11 cases with endometrial cancer, 1 case with ovarian cancer who accepted radical hysterectomy, 2 cases with benign tumor who accepted resection, 2 cases accepted inguinal lymph node dissection, 1 case with rectal cancer accepted radical resection.There were 30 cases with history of radiation therapy and 23 cases with history of erysipelas recurrent((2.1±3.9)/year). The limb swelling degree in preoperative and postoperative patients was explored using one-way analysis of variance with replicate measures and paired sample t-test. Meanwhile the incidence of lymphogenous infection was used as an evaluation of operation efficacy. Results: The mean lower limb circumference difference at 7 days, 6 months and 12 months was (0.17±1.36)cm, (1.25±1.62)cm and(1.58±1.56)cm, respectively, which was significantly decreased compared with preoperative((4.92±2.16)cm) (t=-5.712, -5.777, -5.765; all P<0.01). The mean lower limb volume difference at 7 days, 6 months and 12 months was (522±799)ml, (726±973)ml and (889±895)ml, respectively, which was significantly decreased compared with preoperative((2 729±1 335) ml)(t=-5.905, -6.093, -5.777; all P<0.01). The incidence of erysipelas was 0.0(0.0, 0.0)/6 months within 6 months after operation and 0.0(0.0, 0.0)/6 months within 6-12 months after operation, which was significantly lower than that before operation(0.0(0.0, 2.0)/year). The feeling of tightness and heaviness of the limb was significantly improved compared with preoperative. Conclusion: Liposuction combined with lymphatico-venous anastomosis is an effective method for the treatment of secondary lymphedema of the lower limbs.
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Kim J, Lee W, Jang J, Lim E, Koh Y, Park H, Kim P, Hwang B, Kim C, Seung K, Chang K. P3652Effect of euthyroid sick syndrome on long-term clinical outcome in patients with preserved left ventricular function after acute myocardial infarction. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx504.p3652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Chang K, Huang CH, Lee IK, Lu PL, Lin CY, Chen TC, Lai PC, Hsieh HC, Yu HL, Hung CH, Wu MC, Chin YY, Huang CC, Wu DC, Chen YH. Differences in Mortality and Clinical Manifestations of Dengue Hemorrhagic Fever in Taiwan in Different Years: A Comparison for Cases in 2014 and 2015 Epidemics. Am J Trop Med Hyg 2017; 97:361-368. [PMID: 28722609 DOI: 10.4269/ajtmh.16-1018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
People in southern Taiwan experienced two major dengue outbreaks in 2014 and 2015. The mortality and clinical features were very different between these 2 years. Dengue virus serotype 1 (DENV-1) caused epidemic outbreak in 2014 and DENV-2 was predominant in 2015. The characteristics of dengue hemorrhagic fever (DHF) cases in the 2 years was analyzed. We conducted a retrospective chart review to analyze the clinical and laboratory features of 206 adult patients with DHF in southern Taiwan in 2014 and 2015. The mortality rate of DHF cases in 2015 was higher than that of cases in 2014 (38.7% versus 12.4%, P < 0.0001). Compared with cases in 2014, DHF cases in 2015 had more complications, such as gastrointestinal bleeding (78.5% versus 61.9%, P = 0.01), severe hepatitis (30.1% versus 8%, P < 0.0001), and myocarditis (14% versus 0.9%, P < 0.0001). Among the mortality cases, diabetes, chronic renal failure, proton-pump inhibitors using, platelet transfusion, and Charlson comorbidity index score (Charlson score) were also higher in 2015. Multivariate analysis for the mortality cases revealed that the risk factors were Charlson score ≥ 5 (P = 0.02, odds ratio [OR] = 4.07, 95% confidence interval [CI] = 1.244-13.307), severe hepatitis (P < 0.0001, OR = 11.97, 95% CI = 3.831-37.396), and acute renal failure (P < 0.0001, OR = 98.76, 95% CI = 10.847-899.22). DHF cases in 2015 had higher mortality and more complications, such as gastrointestinal bleeding, severe hepatitis, and myocarditis, than in 2014 in southern Taiwan. In the 2-year DHF case series, Charlson score ≥ 5, severe hepatitis, and acute renal failure were independent significant variables for mortality.
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Williams J, Zhou F, Sun T, Tao Z, Chang K, Makino K, Berz M, Duxbury PM, Ruan CY. Active control of bright electron beams with RF optics for femtosecond microscopy. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:044035. [PMID: 28868325 PMCID: PMC5565489 DOI: 10.1063/1.4999456] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/08/2017] [Indexed: 06/07/2023]
Abstract
A frontier challenge in implementing femtosecond electron microscopy is to gain precise optical control of intense beams to mitigate collective space charge effects for significantly improving the throughput. Here, we explore the flexible uses of an RF cavity as a longitudinal lens in a high-intensity beam column for condensing the electron beams both temporally and spectrally, relevant to the design of ultrafast electron microscopy. Through the introduction of a novel atomic grating approach for characterization of electron bunch phase space and control optics, we elucidate the principles for predicting and controlling the phase space dynamics to reach optimal compressions at various electron densities and generating conditions. We provide strategies to identify high-brightness modes, achieving ∼100 fs and ∼1 eV resolutions with 106 electrons per bunch, and establish the scaling of performance for different bunch charges. These results benchmark the sensitivity and resolution from the fundamental beam brightness perspective and also validate the adaptive optics concept to enable delicate control of the density-dependent phase space structures to optimize the performance, including delivering ultrashort, monochromatic, high-dose, or coherent electron bunches.
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Lee Y, Kim JY, Choi Y, Kim YR, Kim SH, Koh YS, Kim JH, Jang SW, Lee MY, Rho TH, Chang K, Oh YS. P1798Predictors of recovery of atrioventricular conduction disorders after transcatheter aortic valve implantation. Europace 2017. [DOI: 10.1093/ehjci/eux161.107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Hung CH, Huang CH, Wang L, Huang CC, Wu MC, Chin YY, Lin CY, Chang K, Wu DC, Chen YH. IL-28 and IL-29 as protective markers in subject with dengue fever. Med Microbiol Immunol 2017; 206:217-223. [PMID: 28238051 DOI: 10.1007/s00430-017-0498-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 02/09/2017] [Indexed: 12/28/2022]
Abstract
About 400 million people every year are estimated to contract dengue virus infection, which causes prolonged morbidity and sometimes mortality. Interleukin (IL)-28 and IL-29 are relatively newly discovered cytokines and play an important role in our immune defense against pathogens, especially for viral infection. In the present study, we investigated serum IL-28 and IL-29 expression and the relationship to clinical and laboratory parameters in patients with dengue virus infection. Adult patients with dengue (n = 45) and control group (n = 24) were included prospectively. Clinical symptoms and laboratory data were collected from every patient. We investigated IL-28 and IL-29 levels in serum by ELISA. The concentrations of serum IL-28 and IL-29 were significantly higher in subjects with dengue when compared to those of control group. The patients with higher serum IL-28 and IL-29 levels had significantly lower ALAT and peripheral blood neutrophil percentage, but higher peripheral platelet, total white blood cell (WBC), monocyte, and lymphocyte counts. Patients with higher serum IL-28 and IL-29 levels also had more flu-like symptoms, but less vomiting. Increased level of IL-28 and IL-29 was associated with better liver function, platelet and WBC numbers and clinical symptom in subjects with dengue and could potentially serve as a protective marker.
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Lo W, Chuang J, Ko C, Chou S, Chen R, Chang K, Hung J, Su W, Chang W, Hsu T. P05.06 Upregulation of CYP17A1 by Sp1-mediated DNA demethylation confers temozolomide resistance through DHEA-mediated protection in glioma. Neuro Oncol 2017. [DOI: 10.1093/neuonc/nox036.173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Chang K, Eichler A, Rhensius J, Lorenzelli L, Degen CL. Nanoscale Imaging of Current Density with a Single-Spin Magnetometer. NANO LETTERS 2017; 17:2367-2373. [PMID: 28329445 DOI: 10.1021/acs.nanolett.6b05304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Charge transport in nanostructures and thin films is fundamental to many phenomena and processes in science and technology, ranging from quantum effects and electronic correlations in mesoscopic physics, to integrated charge- or spin-based electronic circuits, to photoactive layers in energy research. Direct visualization of the charge flow in such structures is challenging due to their nanometer size and the itinerant nature of currents. In this work, we demonstrate noninvasive magnetic imaging of current density in two-dimensional conductor networks including metallic nanowires and carbon nanotubes. Our sensor is the electronic spin of a diamond nitrogen-vacancy center attached to a scanning tip and operated under ambient conditions. Using a differential measurement technique, we detect DC currents down to a few μA with a current density noise floor of ∼2 × 104 A/cm2. Reconstructed images have a spatial resolution of typically 50 nm, with a best-effort value of 22 nm. Current density imaging offers a new route for studying electronic transport and conductance variations in two-dimensional materials and devices, with many exciting applications in condensed matter physics and materials science.
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Tsai JJ, Chang JS, Chang K, Chen PC, Liu LT, Ho TC, Tan SS, Chien YW, Lo YC, Perng GC. Transient Monocytosis Subjugates Low Platelet Count in Adult Dengue Patients. Biomed Hub 2017; 2:1-16. [PMID: 31988894 PMCID: PMC6945895 DOI: 10.1159/000457785] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 01/21/2017] [Indexed: 01/10/2023] Open
Abstract
Background Dengue is one of the most important vector-borne human viral diseases globally. The kinetic changes of hematological parameters of dengue in adult Taiwanese patients have seldomly been systematically investigated and characterized. Methodology/Principal Findings Serial laboratory data of 1,015 adult patients who were diagnosed with dengue virus serotype 2 (DENV2) and 3 (DENV3) infections in southern Taiwan were retrospectively examined. Prominent parameters were verified with specimens from a 2015 dengue outbreak. Higher absolute monocyte counts on day 5 in severe patients than mild fever subjects after the onset of fever was seen. The absolute number of monocytes was significantly greater in those with DENV2 than DENV3 infections in spite of subtle differences in laboratory tests. Platelet counts were lowest and activated partial thromboplastin time was highest on day 5 in patients with severe conditions. In addition, sudden downward platelet counts corresponding to a transient surge of monocytes on day 4 onward was observed. Fluorescence-activated cell sorting analysis of peripheral blood mononuclear cells obtained from acute dengue patients and experimental investigations revealed that phagocytic effects of innate immune cells contribute to thrombocytopenia in dengue patients. Conclusion Innate phagocytic cells play an essential role in low platelet counts in adult patients with dengue virus infections.
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Kim MHY, Thibeault SA, Wilson JW, Simonsen LC, Heilbronn L, Chang K, Kiefer RL, Weakley JA, Maahs HG. Development and Testing of in situ Materials for Human Exploration of Mars. HIGH PERFORM POLYM 2016. [DOI: 10.1088/0954-0083/12/1/302] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Interplanetary space radiation poses a serious health hazard in long-term manned space missions. Natural Martian surface materials are evaluated for their potential use as radiation shields for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley’s HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To make structural shielding composite materials from constituents of the Martian atmosphere and from Martian regolith for Martian surface habitats, schemes for synthesizing polyimide from the Martian atmosphere and for processing Martian regolith/polyimide composites are proposed. Theoretical predictions of the shielding properties of these composites are computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance the structural properties also enhances the shielding properties of these composites because of the added hydrogenous constituents. Laboratory testing of regolith simulant/polyimide composites is planned in order to validate this prediction and also to measure various structural properties.
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Chang K, Chen CD, Shih CM, Lee TC, Wu MT, Wu DC, Chen YH, Hung CH, Wu MC, Huang CC, Lee CH, Ho CK. Time-Lagging Interplay Effect and Excess Risk of Meteorological/Mosquito Parameters and Petrochemical Gas Explosion on Dengue Incidence. Sci Rep 2016; 6:35028. [PMID: 27733774 PMCID: PMC5062066 DOI: 10.1038/srep35028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/21/2016] [Indexed: 11/09/2022] Open
Abstract
In Kaohsiung, a metropolitan city in Taiwan at high risk of dengue epidemic, weather factors combined with an accidental petrochemical gas explosion (PGE) may affect mosquito‒human dynamics in 2014. Generalized estimating equations with lagged-time Poisson regression analyses were used to evaluate the effect of meteorological/mosquito parameters and PGE on dengue incidences (2000–2014) in Kaohsiung. Increased minimum temperatures rendered a 2- and 3-month lagging interactive effect on higher dengue risks, and higher rainfall exhibited a 1- and 2-month lagging interplay effect on lower risks (interaction, P ≤ 0.001). The dengue risk was significantly higher than that in a large-scale outbreak year (2002) from week 5 after PGE accident in 2014 (2.9‒8.3-fold for weeks 5‒22). The greatest cross-correlation of dengue incidences in the PGE-affected and PGE-neighboring districts was identified at weeks 1 after the PGE (rs = 0.956, P < 0.001). Compared with the reference years, the combined effect of minimum temperature, rainfall, and PGE accounted for 75.1% of excess dengue risk in 2014. In conclusion, time-lagging interplay effects from minimum temperature and rainfall may be respectively associated with early and near environments facilitating dengue transmission. Events that interact with weather and influence mosquito‒human dynamics, such as PGEs, should not be ignored in dengue prevention and control.
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Amii R, Laveman E, Alvarez S, Garcia A, Chang K, Chiem A. 364 Sonographic Criteria for Cholecystitis Alone Do Not Predict the Need for Emergent Cholecystectomy: A 3-Month Longitudinal Study. Ann Emerg Med 2016. [DOI: 10.1016/j.annemergmed.2016.08.381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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