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Wang YT, Lin MR, Chen WC, Wu WH, Wang FS. Optimization of a modeling platform to predict oncogenes from genome-scale metabolic networks of non-small-cell lung cancers. FEBS Open Bio 2021. [PMID: 34137202 PMCID: PMC8329960 DOI: 10.1002/2211-5463.13231] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/19/2021] [Accepted: 06/16/2021] [Indexed: 12/25/2022] Open
Abstract
Cancer cell dysregulations result in the abnormal regulation of cellular metabolic pathways. By simulating this metabolic reprogramming using constraint-based modeling approaches, oncogenes can be predicted, and this knowledge can be used in prognosis and treatment. We introduced a trilevel optimization problem describing metabolic reprogramming for inferring oncogenes. First, this study used RNA-Seq expression data of lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) samples and their healthy counterparts to reconstruct tissue-specific genome-scale metabolic models and subsequently build the flux distribution pattern that provided a measure for the oncogene inference optimization problem for determining tumorigenesis. The platform detected 45 genes for LUAD and 84 genes for LUSC that lead to tumorigenesis. A high level of differentially expressed genes was not an essential factor for determining tumorigenesis. The platform indicated that pyruvate kinase (PKM), a well-known oncogene with a low level of differential gene expression in LUAD and LUSC, had the highest fitness among the predicted oncogenes based on computation. By contrast, pyruvate kinase L/R (PKLR), an isozyme of PKM, had a high level of differential gene expression in both cancers. Phosphatidylserine synthase 1 (PTDSS1), an oncogene in LUAD, was inferred to have a low level of differential gene expression, and overexpression could significantly reduce survival probability. According to the factor analysis, PTDSS1 characteristics were close to those of the template, but they were unobvious in LUSC. Angiotensin-converting enzyme 2 (ACE2) has recently garnered widespread interest as the SARS-CoV-2 virus receptor. Moreover, we determined that ACE2 is an oncogene of LUSC but not of LUAD. The platform developed in this study can identify oncogenes with low levels of differential expression and be used to identify potential therapeutic targets for cancer treatment.
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Chen WC, Erwin R, Tsai P, Hassan MT, Hadad N, Majkrzak CF. A large beam high efficiency radio frequency neutron spin flipper. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:063906. [PMID: 34243533 PMCID: PMC10398713 DOI: 10.1063/5.0045687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/06/2021] [Indexed: 06/13/2023]
Abstract
A design for a radio frequency (RF) neutron spin flipper obtained from magneto-static and neutron spin transport simulations is presented. The RF flipper constructed from this design provides a flipping probability of 0.999 or better for a beam size 6 cm wide and 15 cm high and a wavelength band between 0.4 and 0.6 nm. Three permanent magnet guide field sections with air gaps provide a linear field gradient along the beam propagation direction over a large cross-sectional area. An RF oscillator based on coupling the resonant coil of a Hartley oscillator to the excitation coil was developed, which provides a higher current and, thereby, a larger RF amplitude, as compared to a conventional RF power amplifier. Two opaque He3 neutron spin filters were employed to measure the flipping probability of the flipper with very high precision. A spatially uniform flipping probability of 0.9995(2) or higher was measured over the large cross-sectional area neutron guide. This RF neutron spin flipper will be employed in a polychromatic beam reflectometer at the National Institute of Standards and Technology Center for Neutron Research. This design can be applied to other polarized neutron instruments or applications requiring a very high continuous flipping probability of the neutron spin for a large cross-sectional area beam.
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Li ZY, Liu WZ, Guang H, Chen WC, Yang YH. Silencing of long noncoding RNA H19 inhibited invasion and migration of papillary thyroid cancer cells via microRNA-138-dependent regulating of LRRK2. J BIOL REG HOMEOS AG 2021; 35:253-258. [PMID: 33506668 DOI: 10.23812/20-422-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lu N, Wang C, Chen WC, Li H, Song C, Tiwari R, Xu Y, Yue LQ. Leverage multiple real-world data sources in single-arm medical device clinical studies. J Biopharm Stat 2021; 32:107-123. [PMID: 33844621 DOI: 10.1080/10543406.2021.1897994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The interest in utilizing real-world data (RWD) has been considerably increasing in medical product development and evaluation. With proper usage and analysis of high-quality real-world data, real-world evidence (RWE) can be generated to inform regulatory and healthcare decision-making. This paper proposes a study design and data analysis approach for a prospective, single-arm clinical study that is supplemented with patients from multiple real-world data sources containing patient-level covariate and outcome data. After the amount of information to be borrowed from each real-world data source is determined, the propensity score-integrated composite likelihood method is applied to obtain an estimate of the parameter of interest based on data from the prospective clinical study and this real-world data source. This method is applied to each real-world data source. The final estimate of the parameter of interest is then obtained by taking a weighted average of all these estimates. The performance of the proposed approach is evaluated via a simulation study. A hypothetical example is presented to illustrate how to implement the proposed approach.
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Wang CY, Lin YW, Chuang C, Yang CH, Patel DK, Chen SZ, Yeh CC, Chen WC, Lin CC, Chen YH, Wang WH, Sankar R, Chou FC, Kruskopf M, Elmquist RE, Liang CT. Magnetotransport in hybrid InSe/monolayer graphene on SiC. NANOTECHNOLOGY 2021; 32:155704. [PMID: 33373982 DOI: 10.1088/1361-6528/abd726] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The magnetotransport properties of a hybrid InSe/monolayer graphene in a SiC system are systematically studied. Compared to those of its bare graphene counterpart, in InSe/graphene, we can effectively modify the carrier density, mobility, effective mass, and electron-electron (e-e) interactions enhanced by weak disorder. We show that in bare graphene and hybrid InSe/graphene systems, the logarithmic temperature (lnT) dependence of the Hall slope R H = δR xy /δB = δρ xy /δB can be used to probe e-e interaction effects at various temperatures even when the measured resistivity does not show a lnT dependence due to strong electron-phonon scattering. Nevertheless, one needs to be certain that the change of R H is not caused by an increase of the carrier density by checking the magnetic field position of the longitudinal resistivity minimum at different temperatures. Given the current challenges in gating graphene on SiC with a suitable dielectric layer, our results suggest that capping a van der Waals material on graphene is an effective way to modify the electronic properties of monolayer graphene on SiC.
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Chen WC, Li H, Wang C, Lu N, Song C, Tiwari R, Xu Y, Yue LQ. Evaluation of diagnostic tests for low prevalence diseases: a statistical approach for leveraging real-world data to accelerate the study. J Biopharm Stat 2021; 31:375-390. [PMID: 33615997 DOI: 10.1080/10543406.2021.1877724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The evaluation of diagnostic tests usually involves statistical inference for its sensitivity. As sensitivity is defined as the probability that the test result will be positive when the target condition is present, the key study design consideration of sample size is the determination of the number of subjects with the target condition such that the estimation has adequate precision, or the hypothesis testing has adequate power. Traditionally, one may rely on prospective screening of subjects to obtain the required sample size, which means that if the prevalence of the disease is very low, a large number of subjects would need to be screened, increasing the study duration and cost. In this paper, we consider the possibility of substantially reducing the length and cost of a clinical study by leveraging subjects from a real-world data (RWD) source, focusing specifically on the diagnostic test for the cancer of interest. Using the propensity score methodology, we developed a procedure which ensures that the real-world subjects being leveraged are similar to their prospectively enrolled counterparts, thereby making the leveraging more justified. The procedure allows the down-weighting of the real-world subjects, which can be achieved by either using a Frequentist's method based on the composite likelihood or a Bayesian method based on the power prior. The proposed approach can be applied to the evaluation of any diagnostic test and it is not limited to the current clinical study regarding a cancer diagnostic test. Notably, this paper is in close alignment with a recently released draft framework by the Medical Device Innovation Consortium (MDIC) on real-world clinical evidence and in vitro diagnostics, being a showcase of appropriately leveraging real-world data in diagnostic test evaluation for diseases with low prevalence to support regulatory decision-making.
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Vural S, Baumgartner M, Lichtner P, Eckstein G, Hariry H, Chen WC, Ruzicka T, Melnik B, Plewig G, Wagner M, Giehl KA. Investigation of gamma secretase gene complex mutations in German population with Hidradenitis suppurativa designate a complex polygenic heritage. J Eur Acad Dermatol Venereol 2021; 35:1386-1392. [PMID: 33559291 DOI: 10.1111/jdv.17163] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 01/14/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Hidradenitis suppurativa (HS) is a chronic inflammatory disease affecting apocrine gland-bearing skin in the axilla, groin and under the breasts. Mutations of the gamma secretase gene complex, which is essential in the activation of Notch signalling pathways, were shown in some families with HS and in a few sporadic cases. Although an imbalance in Notch signalling is implicated in the pathogenesis, the exact mechanism of HS development is yet unknown. OBJECTIVES We aim to investigate the genetic basis of HS by determining the presence of mutations of gamma secretase gene complex in a cohort of HS patients and by searching for a disease-causing pathogenic variant in a multi-generational HS family using parametric linkage analysis. METHODS Thirty-eight patients clinically diagnosed with HS were included in this study. All exons and exon-intron boundaries of the genes encoding gamma secretase complex consisting of six genes: APH1A, APH1B, PSENEN, NCSTN, PSEN1 and PSEN2 were sequenced by Sanger technique. Genetic mapping with parametric linkage analysis for the patients in the family was performed with eight affected and four healthy individuals. The logarithm of odds was calculated. RESULTS In a sporadic patient with early-onset, severe lesions in axilla and groin, a novel single-nucleotide deletion causing frameshift in exon 1 of the NCSTN gene was identified ((NM_015331.3): c.38delG, p.(Gly13Glufs*15)). The LOD score of 1.5 was never exceeded in any region of the genome, pointing towards intricate multi-genic inheritance pattern within the affected family. CONCLUSIONS The gamma secretase gene complex mutations were rare in our cohort (3.2%). Besides, our analysis indicates a possible complex multi-genic inheritance in a seemingly autosomal dominantly inherited large HS family. Genetics of both familial and sporadic HS may be complicated in most cases, and the role of other potential genes such as autoinflammatory and modifier genes as well as environmental factors may influence the pathogenesis.
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Li H, Chen WC, Lu N, Song C, Wang C, Tiwari R, Xu Y, Yue LQ. Mitigating Study Power Loss Caused by Clinical Trial Disruptions Due to the COVID-19 Pandemic: Leveraging External Data via Propensity Score-Integrated Approaches. Stat Biopharm Res 2021. [DOI: 10.1080/19466315.2020.1860813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Chen FR, Zheng LM, Wu DC, Gong HM, Cen H, Chen WC. [Regulatory relationship between lncRNA KCNQ1OT1 and miR-146a-3p in preeclampsia]. ZHONGHUA FU CHAN KE ZA ZHI 2020; 55:535-543. [PMID: 32854478 DOI: 10.3760/cma.j.cn112141-20200322-00246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To observe the changes of the expression level of long non-coding RNA (lncRNA) KCNQ1OT1 and microRNA (miR)-146a-3p in placenta tissues of preeclampsia (PE) patients, as well as their effect and mechanism on the biological functions of trophoblast cells. Methods: A total of 45 cases of hospitalized PE patients in Hainan General Hospital from July 2017 to July 2018 were selected as the PE group, 55 normal pregnant women during the same period were chosed as the control group. The expression level of KCNQ1OT1 mRNA and miR-146a-3p in the placenta tissues between two groups were detected by using quantitative real time (qRT)-PCR. Pearson's test was furtherly analyzed the correlation between them. Human trophoblast cell line (HTR8/SVneo) were randomly divided into control and lipopolysaccharide (LPS) groups, and then LPS group were divide into four sub-groups,included LPS group, short hairpin RNA (sh)-KCNQ1OT1 (after silencing the expression of KCNQ1OT1), miR-146a-3p inhibitor and sh-KCNQ1OT1+miR-146a-3p inhibitor. The targeting relationship between KCNQ1OT1 and miR-146a-3p were predicted by bioinformatics software and confirmed by luciferase assay. The cell proliferation and invasion capacities were respectively detected by cell counting kit-8 (CCK-8) and transwell assay. The expression level of KCNQ1OT1 mRNA and miR-146a-3p were detected by qRT-PCR and the protein expression level of CXC chemokine ligand 12 (CXCL12) and CXC chemokine receptor type 4 (CXCR4) were tested by western blot. Results: (1) The mRNA expression level of KCNQ1OT1 in the placenta of PE group was lower than that of control group (0.23±0.03 vs 0.51±0.04, P<0.05), and the miR-146a-3p expression level was higher than that of the control group (0.49±0.03 vs 0.31±0.03, P<0.05), there were statistical significant differences between the two groups. (2) Luciferase assay showed that there was a targeting relationship between KCNQ1OT1 and mir-146a-3p. Compared with the control group, the mRNA expression level of KCNQ1OT1 in the LPS group were significantly decreased (0.91±0.03 vs 0.35±0.03, P<0.05), and the expression level of miR-146a-3p were significantly increased (0.22±0.03 vs 0.63±0.04, P<0.05). The cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 significantly reduced in the LPS group compared with control group (all P<0.05). The mRNA expression level of KCNQ1OT1 (0.23±0.03) in the sh-KCNQ1OT1 group were further decreased, the expression of miR-146a-3p (0.85±0.03) were further increased, and the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all further reduced compared with control group,there were significant difference between two groups (all P<0.05). Comparing the miR-146a-3p inhibitor group, and sh-KCNQ1OT1+miR-146a-3p inhibitor group with the sh-KCNQ1OT1 group, respectively, the expression level of KCNQ1OT1 mRNA (0.78±0.04 vs 0.50±0.03) increased, and the expression level of miR-146a-3p (0.42±0.03 vs 0.46±0.03) decreased, the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all increased ,there were statistically significant differences (all P<0.05). Conclusion: KCNQ1OT1 could target the regulation of miR-146a-3p through CXCL12/CXCR4 pathway in the proliferation, invasion an migration of HTR8/SVneo cells, which may be involved in the pathogenesis of PE.
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Chen WC, Chaou CH, Ng CJ, Liu YP, Chang YC. Assessing the effectiveness of pediatric emergency medicine education in emergency medicine residency training: A national survey. HONG KONG J EMERG ME 2020. [DOI: 10.1177/1024907920926312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background: Evaluating the effectiveness of pediatric emergency medicine training is essential to ensure that emergency physicians and emergency medicine residents have sufficient knowledge, skill, and confidence in optimizing care for acute pediatric visits. Although the field of pediatric emergency medicine has experienced phenomenal growth in past decades, it still faces challenges in how to best implement the curriculums in emergency medicine residency training programs. Objectives: Exploring emergency physicians’ and emergency residents’ perspectives on pediatric emergency medicine training in emergency residency training programs in Taiwan through a nationwide survey. Methods: The survey was distributed to 1281 emergency physicians and emergency medicine residents in 43 teaching hospitals. The survey inquired about demographic data, hospital type, rank of proctored trainers and assessors, and the setting of pediatric emergency medicine training. Participants’ confidence in managing acute pediatric visits and their satisfaction and reflections of their pediatric emergency medicine training were explored. Results: In all, 258 responses were received from 117 residents and 141 emergency physicians. Seventy-seven percent reported working in medical centers. Clinical supervision was primarily performed by pediatric attending physicians and emergency physicians. Fifty-eight percent of participants felt satisfied with their pediatric emergency medicine training. However, only 52.3% felt confident managing acute pediatric visits, which was attributed to inadequate exposure to pediatric patients. Residents noted lack of confidence in managing newborns, infants, and clinical procedures. Therefore, simulation training and point-of-care ultrasound learning were considered advantageous. Conclusion: The pediatric emergency medicine training in emergency medicine residency programs is diverse in intensive care training, supervisors, and assessors. Surveys demonstrate that learning experience in pediatric wards and emergency department rotations is associated with overall satisfaction with pediatric emergency medicine training; inadequate exposure to pediatric patients contributed to learners having less confidence. Emergency medicine residency program reform might focus on adequate hands-on pediatric patient care.
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Chen WC, Wang C, Li H, Lu N, Tiwari R, Xu Y, Yue LQ. Propensity score-integrated composite likelihood approach for augmenting the control arm of a randomized controlled trial by incorporating real-world data. J Biopharm Stat 2020; 30:508-520. [DOI: 10.1080/10543406.2020.1730877] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Cheng LC, Chen WC, Santhoshkumar R, Chao TH, Cheng MJ, Cheng CH. Synthesis of Quinolinium Salts from N
-Substituted Anilines, Aldehydes, Alkynes, and Acids: Theoretical Understanding of the Mechanism and Regioselectivity. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Liu CY, Angamuthu V, Chen WC, Hou DR. Synthesis of Methyl l-Kijanosides by Regio- and Stereoselective Ring Opening of 2-Oxazolidinone -Fused Aziridines. Org Lett 2020; 22:2246-2250. [PMID: 32115955 DOI: 10.1021/acs.orglett.0c00443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Kijanose is one of the most highly functionalized deoxysugars found in nature and a challenging synthetic target. We found that the ring opening of trisubstituted, 2-oxazolidinone-fused aziridines is regio- and stereoselective, and the azide adduct has the same stereochemistry as that of kijanose after converting the azido to a nitro group. Therefore, both α- and β-methyl l-kijanosides were prepared from ethyl l-lactate in 14% total yield.
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Chen WC, Lin WC, Yang CH, Wu CN, Luo SD. Autonomic dysfunction as an independent risk factor for uncontrolled inflammation in chronic rhinosinusitis following functional endoscopic sinus surgery. Rhinology 2019; 0:2224. [PMID: 31886799 DOI: 10.4193/rhin19.238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) is a multi-factorial disorder that causes systemic symptoms beyond rhinologic symptoms alone. A possible association between autonomic nervous system (ANS) dysfunction and CRS has been identified; however, few studies have confirmed this observation. In this study, we prospectively measured changes in ANS dysfunction symptoms following functional endoscopic sinus surgery (FESS) and explored the impact of ANS dysfunction on surgical outcomes of CRS. METHODOLOGY Patients diagnosed with CRS who consented to surgical intervention were included prospectively. All patients completed the Sino-nasal Outcome Test-22 (SNOT-22) and the 31-item Composite Autonomic Symptom Score (COMPASS 31) questionnaires before the operation and during the follow-up period. Clinical demographic data, Lund-Mackay, and modified Lund-Kennedy scores were recorded and measured. RESULTS A total of 102 patients were enrolled. The median SNOT-22 and COMPASS 31 scores significantly improved following FESS from 43.0 to 14.0 and 21.0 to 11.2 (all P less than 0.001), respectively. FESS led to a significant reduction in the prevalence of various ANS dysfunction symptoms. In multivariate analyses, revision surgeries (odds ratio [OR] 5.012, 95% confidence interval [CI] 1.52416.489; P=0.008), CRS with nasal polyps (OR 4.071, 95% CI 1.454-11.40; P=0.008), and higher Pre-FESS COMPASS 31 scores (OR 1.043, 95% CI 1.003-1.084; P=0.036) were independent risk factors for uncontrolled inflammation following FESS. CONCLUSIONS ANS dysfunction symptoms are prevalent in CRS and higher preoperative COMPASS 31 scores correspond with poor surgical outcomes. Following FESS, the majority of ANS dysfunction symptoms can be alleviated. Further investigations are required to explore the possible mechanism of how ANS is involved in the pathogenesis of CRS.
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Wang C, Lu N, Chen WC, Li H, Tiwari R, Xu Y, Yue LQ. Propensity score-integrated composite likelihood approach for incorporating real-world evidence in single-arm clinical studies. J Biopharm Stat 2019; 30:495-507. [DOI: 10.1080/10543406.2019.1684309] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Wang C, Li H, Chen WC, Lu N, Tiwari R, Xu Y, Yue LQ. Propensity score-integrated power prior approach for incorporating real-world evidence in single-arm clinical studies. J Biopharm Stat 2019; 29:731-748. [DOI: 10.1080/10543406.2019.1657133] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Kim MG, Winn B, Chi S, Savici AT, Rodriguez-Rivera JA, Chen WC, Xu X, Li Y, Kim JW, Cheong SW, Kiryukhin V. Spin-liquid-like state in pure and Mn-doped TbInO 3 with a nearly triangular lattice. PHYSICAL REVIEW. B 2019; 100:10.1103/PhysRevB.100.024405. [PMID: 38712019 PMCID: PMC11071068 DOI: 10.1103/physrevb.100.024405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Inelastic neutron scattering studies in single crystals of TbInO3 and TbIn0.95Mn0.05O3 with nearly triangular antiferromagnetic lattice are reported. At low energies, a broad and apparently gapless continuum of magnetic excitations, located at the triangular lattice (TL) Brillouin zone boundary, is observed. The data are well described by the uncorrelated nearest-neighbor valence bonds model. At higher energies, a broad excitation branch dispersing from the TL zone boundary is observed. No signs of static magnetic order are found down to the temperatures two orders of magnitude smaller than the effective interaction energy. The fluctuating magnetic moment exceeds two-thirds of the Tb3+ free-ion value and is confined to the TL plane. These observations are consistent with a TL-based spin liquid state in TbInO3.
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Zhang J, Pajerowski DM, Botana AS, Zheng H, Harriger L, Rodriguez-Rivera J, Ruff JPC, Schreiber NJ, Wang B, Chen YS, Chen WC, Norman MR, Rosenkranz S, Mitchell JF, Phelan D. Spin Stripe Order in a Square Planar Trilayer Nickelate. PHYSICAL REVIEW LETTERS 2019; 122:247201. [PMID: 31322403 DOI: 10.1103/physrevlett.122.247201] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 03/14/2019] [Indexed: 06/10/2023]
Abstract
Trilayer nickelates, which exhibit a high degree of orbital polarization combined with an electron count (d^{8.67}) corresponding to overdoped cuprates, have been identified as a promising candidate platform for achieving high-T_{c} superconductivity. One such material, La_{4}Ni_{3}O_{8}, undergoes a semiconductor-insulator transition at ∼105 K, which was recently shown to arise from the formation of charge stripes. However, an outstanding issue has been the origin of an anomaly in the magnetic susceptibility at the transition and whether it signifies the formation of spin stripes akin to single layer nickelates. Here we report single crystal neutron diffraction measurements (both polarized and unpolarized) that establish that the ground state is indeed magnetic. The ordering is modeled as antiferromagnetic spin stripes that are commensurate with the charge stripes, the magnetic ordering occurring in individual trilayers that are essentially uncorrelated along the crystallographic c axis. A comparison of the charge and spin stripe order parameters reveals that, in contrast to single-layer nickelates such as La_{2-x}Sr_{x}NiO_{4} as well as related quasi-2D oxides including manganites, cobaltates, and cuprates, these orders uniquely appear simultaneously, thus demonstrating a stronger coupling between spin and charge than in these related low-dimensional correlated oxides.
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Baal JD, Chen WC, Solomon DA, Pai JS, Lucas CH, Hara JH, Oberheim Bush NA, McDermott MW, Raleigh DR, Villanueva-Meyer JE. Preoperative MR Imaging to Differentiate Chordoid Meningiomas from Other Meningioma Histologic Subtypes. AJNR Am J Neuroradiol 2019; 40:433-439. [PMID: 30819773 DOI: 10.3174/ajnr.a5996] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/14/2019] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND PURPOSE Chordoid meningiomas are uncommon WHO grade II primary intracranial neoplasms that possess unique chordoid histology and follow an aggressive clinical course. Our aim was to assess the utility of qualitative MR imaging features and quantitative apparent diffusion coefficient values as distinguishing preoperative MR imaging metrics to identify and differentiate chordoid histology from other meningioma histologic subtypes. MATERIALS AND METHODS Twenty-one patients with meningiomas with chordoid histology, which included both chordoid meningiomas (>50% chordoid histology) and meningiomas with focal chordoid histology (<50% chordoid histology) with available preoperative MR imaging examinations, including diffusion-weighted imaging, were identified. Qualitative imaging features and quantitative ADC values were compared between meningiomas with chordoid histology and 42 nonchordoid meningiomas (29 WHO grade I, eleven WHO grade II, and 2 WHO grade III). RESULTS The median ADC (10-3mm2/s) of meningiomas with chordoid histology was significantly higher than nonchordoid meningiomas (1.16 versus 0.92, P < .001), as was the median normalized ADC (1.60 versus 1.19, P < .001). In subgroup analysis, the median and normalized ADC values of chordoid meningiomas (n = 11) were significantly higher than those in meningiomas with focal chordoid histology (n = 10, P < .001 and P < .001, respectively) or nonchordoid meningiomas (n = 42, P < .001 and <0.001, respectively). Median and normalized ADC values were not significantly different between the meningiomas with focal chordoid histology and nonchordoid meningiomas (P = .816 and .301, respectively). Among the qualitative imaging features, only DWI signal intensity was significantly associated with meningiomas with chordoid histology diagnosis. CONCLUSIONS ADC values are higher in chordoid compared with nonchordoid meningiomas and may be used to discriminate the degree of chordoid histology in meningiomas. While qualitative MR imaging features do not strongly discriminate chordoid from nonchordoid meningiomas, DWI may allow preoperative identification of chordoid meningiomas.
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Li MY, Zhang DQ, Lu X, Chen WC. [Comparison of two serological methods in screening gastric cancer and its precancerous condition]. ZHONGHUA NEI KE ZA ZHI 2019; 57:907-911. [PMID: 30486559 DOI: 10.3760/cma.j.issn.0578-1426.2018.12.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To compare the diagnostic value of the old "ABC" method [serum pepsinogen(PG) combined with Helicobacter pylori (Hp) IgG antibody] and the new "ABC" method [serum pepsinogen plus gastrin-17(G-17)] in screening gastric cancer and its precancerous condition. Methods: Serum PG, G-17 and Hp-IgG were quantified by enzyme-linked immunosorbent assay (ELISA) in 278 subjects. Subjects were grouped according to the criteria of two methods. The gastroscopy and pathological biopsy were gold standard. Results: The positive rate of old "ABC" method was 74.46% (207/278), which was 54.68% of new "ABC" method (151/278). For the diagnosis of gastric cancer, the sensitivity and specificity of the old "ABC" method were 90.74% and 29.46% respectively, with diagnostic coincidence rate 41.37%. The sensitivity and specificity of the new "ABC" method were 92.59% and 54.46% respectively, with diagnostic coincidence rate 61.87%. As to the diagnosis of pre-cancerous state, the sensitivity and specificity of the old "ABC" method were 75.81% and 36.00%, with diagnostic coincidence rate 58.03%. The sensitivity and specificity of the new "ABC" method were 62.10% and 75.00%, with diagnostic coincidence rate 67.86%. Conclusions: Compared with the old "ABC" method, the new "ABC" method has higher sensitivity, specificity and diagnostic coincidence rate for the diagnosis of gastric cancer, yet higher specificity and lower sensitivity for the diagnosis of precancerous conditions.
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Chen WC, Wu G, Zhang W, Zhu YZ, Zhou Y, Zhang H, Xia XB, Sun PC. [Clinical outcomes of gastric cancer patients received capecitabine based adjuvant chemotherapy and the corresponding pharmacogenomics analysis]. ZHONGHUA YI XUE ZA ZHI 2018; 98:3420-3425. [PMID: 30440137 DOI: 10.3760/cma.j.issn.0376-2491.2018.42.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the association between Thymidine phosphorylase(TYMP)genetic variation and clinical outcomes of postoperative gastric cancer (GC) patients received capecitabine based regimens. Methods: A total of 198 GC patients underwent surgical treatment and received capecitabine based adjuvant chemotherapy were included in this retrospective study. Peripheral blood and the postoperative tissue specimen of the GC patients were collected for the genotyping of polymorphism and TYMP mRNA expression, respectively. The correlation between polymorphism and clinical outcomes and safety of postoperative GC patients were analysed. Results: Located in the upstream, rs11479 was of clinical significance. The prevalence of rs11479 in TYMP among the GC patients were as follows: CC genotype 125 cases (63.13%), CT genotype 65 cases (32.83%), TT genotype 8 cases (4.04%), minor allele frequency of rs11479 is 0.20. The distribution of three genotypes were in accordance with Hardy-Weinberg Equilibrium (P=0.901). The analysis results of patients with different genotypes found that the 3-year disease free survival rate of the patients with CT/TT genotype and CC genotype were 73.97% and 65.60%, respectively, which was statistically significant (P=0.003). In terms of overall survival, the 3-year overall survival rate of the two genotypes were 83.56% and 72.80% (P=0.012), respectively. Adjusted in multivariate Cox regression analysis, CT/TT genotype was an independent favorable factor for disease free survival (OR=0.55, P=0.011). Safety analysis indicated that there was no significant association between genotypes and grade 2 adverse reaction. Additionally, of the 79 postoperative tissue specimens, the results showed that the expression of TYMP in cancer tissues of the patients with CT/TT genotypes were significantly higher than those of the wild type CC genotype patients (P<0.001). Conclusion: The polymorphism rs11479 of TYMP have favorable influence on the clinical outcomes of gastric cancer patients received capecitabine based adjuvant chemotherapy treatment through changing the mRNA expression of TYMP.
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Chuah YY, Lee YY, Chen WC, Kao SS. Sengstaken-Blakemore tube malposition with esophageal rupture. Acta Gastroenterol Belg 2018; 81:447-448. [PMID: 30350541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
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Wu PY, Tsai YC, Hsu CH, Chen WC, Chiu YW. SP497SHORTER TIME BETWEEN SYMPTOMS ONSET AND ANTIBIOTICS ADMINISTRATION IMPROVING OUTCOMES OF PERITONEAL DIALYSIS PERITONITIS. Nephrol Dial Transplant 2018. [DOI: 10.1093/ndt/gfy104.sp497] [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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Tung HY, Chen WC, Ou BR, Yeh JY, Cheng YH, Tsng PH, Hsu MH, Tsai MS, Liang YC. Simultaneous detection of multiple pathogens by multiplex PCR coupled with DNA biochip hybridization. Lab Anim 2017; 52:186-195. [PMID: 28691600 DOI: 10.1177/0023677217718864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Traditional serological enzyme-linked immunosorbent assay (ELISA) is routinely used to monitor pathogens during quarantine in most animal facilities to prevent possible infection. However, the ELISA platform is a single-target assay, and screening all targeted pathogens is time-consuming and laborious. In this study, to increase sensitivity and to reduce diagnosis time for high-throughput processes, multiplex PCR and DNA biochip techniques were combined to develop a multi-pathogen diagnostic method for use instead of routine ELISA. Eight primer sets were designed for multiplex PCR to detect genes from seven targeted bacterial and viral pathogens. DNA-DNA hybridization was conducted on a biochip following the multiple PCR analysis. Using this method, a total of 24 clinical samples were tested, and the result showed that not only single infection but also co-infection by multi-pathogens can be detected. In conclusion, multiplex PCR coupled with a DNA biochip is an efficient method for detecting multi-pathogens in a reaction. This platform is a useful tool for quarantine services and disease prevention in animal facilities.
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Zhang X, Su X, Chen WC, Li Y, Yang ZY, Deng WZ, Deng TC, Yang AK. [ RET/ PTC rearrangement affects multifocal formation of papillary thyroid carcinoma]. ZHONGHUA ER BI YAN HOU TOU JING WAI KE ZA ZHI = CHINESE JOURNAL OF OTORHINOLARYNGOLOGY HEAD AND NECK SURGERY 2017. [PMID: 28635216 DOI: 10.3760/cma.j.issn.1673-0860.2017.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective:RET/PTC gene rearrangement can lead to aberrant activation of tyrosine kinase receptors, which is a common mutation in papillary thyroid carcinoma (PTC). This study focuses on the association of RET/PTC rearrangements with PTC clinical factors. Methods: From January 2011 to December 2013, a total of 114 patients with PTC were enrolled in this study. Clinicopathological parameters, lifestyle, and thyroid hormone levels were collected. RET/PTC rearrangements were detected by TaqMan PCR and verified by Sanger sequencing.Data were analyzed with SPSS software, including chi-square test, Fisher's exact test, Mann-Whitney U test, Student's t-test, and Logistic regression. Results:RET/PTC rearrangements were not found in all paracancerous normal thyroid tissues, and were detected in 23.68% (27/114) of PTC. Further analysis revealed no correlation between RET/PTC rearrangement and thyroid function, clinicopathologic parameters, and lifestyle in the total PTC group or in the subgroup of patients with concomitant diseases (including Hashimoto's thyroiditis and nodular goiter). But in the subgroup of PTC without concomitant disease, RET/PTC rearrangement was associated with tumor multifocal (P=0.018), and RET/PTC-positive PTC patients had an increased risk of tumor multifocal (OR=5.57, 95% CI 1.39-22.33). It was also found that RET/PTC rearrangement was associated with an abnormal increase in TSH level of one month after surgery (P= 0.037). Conclusion: Nodular goiter and Hashimoto 's thyroiditis may be a confounding factor in PTC. RET/PTC rearrangement may play an important role in the occurrence of thyroid carcinoma multifocal after exclusion of this confounding factor.
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