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Chen WC, Bye H, Matejcic M, Amar A, Govender D, Khew YW, Beynon V, Kerr R, Singh E, Prescott NJ, Lewis CM, Babb de Villiers C, Parker MI, Mathew CG. Association of genetic variants in CHEK2 with oesophageal squamous cell carcinoma in the South African Black population. Carcinogenesis 2019; 40:513-520. [PMID: 30753320 PMCID: PMC6556703 DOI: 10.1093/carcin/bgz026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/18/2018] [Accepted: 02/07/2019] [Indexed: 12/15/2022] Open
Abstract
Oesophageal squamous cell carcinoma (OSCC) has a high incidence in southern Africa and a poor prognosis. Limited information is available on the contribution of genetic variants in susceptibility to OSCC in this region. However, recent genome-wide association studies have identified multiple susceptibility loci in Asian and European populations. In this study, we investigated genetic variants from seven OSCC risk loci identified in non-African populations for association with OSCC in the South African Black population. We performed association studies in a total of 1471 cases and 1791 controls from two study sample groups, which included 591 cases and 852 controls from the Western Cape and 880 cases and 939 controls from the Johannesburg region in the Gauteng province. Thereafter, we performed a meta-analysis for 11 variants which had been genotyped in both studies. A single nucleotide polymorphism in the CHEK2 gene, rs1033667, was significantly associated with OSCC [P = 0.002; odds ratio (OR) = 1.176; 95% confidence interval (CI): 1.06-1.30]. However, single nucleotide polymorphisms in the CASP8/ALS2CR12, TMEM173, PLCE1, ALDH2, ATP1B2/TP53 and RUNX1 loci were not associated with the disease (P > 0.05). The lack of association of six of these loci with OSCC in South African populations may reflect different genetic risk factors in non-African and African populations or differences in the genetic architecture of African genomes. The association at CHEK2, a gene with key roles in cell cycle regulation and DNA repair, in an African population provides further support for the contribution of common genetic variants at this locus to the risk of oesophageal cancer.
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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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Andrews C, Fortier B, Hayward A, Lederman R, Petersen L, McBride J, Petersen DC, Ajayi O, Kachambwa P, Seutloali M, Shoko A, Mokhosi M, Hiller R, Adams M, Ongaco C, Pugh E, Romm J, Shelford T, Chinegwundoh F, Adusei B, Mante S, Snyper NY, Agalliu I, Lounsbury DW, Rohan T, Orfanos A, Quintana Y, Jacobson JS, Neugut AI, Gelmann E, Lachance J, Dial C, Diallo TA, Jalloh M, Gueye SM, Kane PMS, Diop H, Ndiaye AJ, Sall AS, Toure-Kane NC, Onyemata E, Abimiku A, Adjei AA, Biritwum R, Gyasi R, Kyei M, Mensah JE, Okine J, Okyne V, Rockson I, Tay E, Tettey Y, Yeboah E, Chen WC, Singh E, Cook MB, Duffy CN, Hsing A, Soo CC, Fernandez P, Irusen H, Aisuodionoe-Shadrach O, Jamda AM, Olabode PO, Nwegbu MM, Ajibola OH, Ajamu OJ, Ambuwa YG, Adebiyi AO, Asuzu M, Ogunbiyi O, Popoola O, Shittu O, Amodu O, Odiaka E, Makinde I, Joffe M, Pentz A, Rebbeck TR. Development, Evaluation, and Implementation of a Pan-African Cancer Research Network: Men of African Descent and Carcinoma of the Prostate. J Glob Oncol 2018; 4:1-14. [PMID: 30260755 PMCID: PMC6223491 DOI: 10.1200/jgo.18.00063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Cancer of the prostate (CaP) is the leading cancer among men in sub-Saharan Africa (SSA). A substantial proportion of these men with CaP are diagnosed at late (usually incurable) stages, yet little is known about the etiology of CaP in SSA. METHODS We established the Men of African Descent and Carcinoma of the Prostate Network, which includes seven SSA centers partnering with five US centers to study the genetics and epidemiology of CaP in SSA. We developed common data elements and instruments, regulatory infrastructure, and biosample collection, processing, and shipping protocols. We tested this infrastructure by collecting epidemiologic, medical record, and genomic data from a total of 311 patients with CaP and 218 matched controls recruited at the seven SSA centers. We extracted genomic DNA from whole blood, buffy coat, or buccal swabs from 265 participants and shipped it to the Center for Inherited Disease Research (Baltimore, MD) and the Centre for Proteomics and Genomics Research (Cape Town, South Africa), where genotypes were generated using the UK Biobank Axiom Array. RESULTS We used common instruments for data collection and entered data into the shared database. Double-entered data from pilot participants showed a 95% to 98% concordance rate, suggesting that data can be collected, entered, and stored with a high degree of accuracy. Genotypes were obtained from 95% of tested DNA samples (100% from blood-derived DNA samples) with high concordance across laboratories. CONCLUSION We provide approaches that can produce high-quality epidemiologic and genomic data in multicenter studies of cancer in SSA.
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Mak D, Sengayi M, Chen WC, Babb de Villiers C, Singh E, Kramvis A. Liver cancer mortality trends in South Africa: 1999-2015. BMC Cancer 2018; 18:798. [PMID: 30086727 PMCID: PMC6081797 DOI: 10.1186/s12885-018-4695-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 07/26/2018] [Indexed: 12/11/2022] Open
Abstract
Background In South Africa (SA), liver cancer (LC) is a public health problem and information is limited. Methods Joinpoint regression analysis was computed for the most recent LC mortality data from Statistics South Africa (StatsSA), by age group, sex and population group. The mortality-to-incidence ratios (MIRs) were calculated as the age-adjusted mortality rate divided by the age-adjusted incidence rate. Results From 1999 to 2015, the overall LC mortality significantly decreased in men (− 4.9%) and women (− 2.7%). Overall a significant decrease was noted in black African men aged 20–29 and 40–49 years, and white women older than 60 years but mortality rates increased among 50–59 and 60–69 year old black African men (from 2010/2009–2015) and women (from 2004/2009–2015). The mortality rates increased with age, and were higher among blacks Africans compared to whites in all age groups - with a peak black African-to-white mortality rate ratio of six in men and three in women at ages 30–39 years. The average MIR for black African men and women was 4 and 3.3 respectively, and 2.2 and 1.8 in their white counterparts. Moreover, decreasing LC mortality rates among younger and the increase in rates in older black Africans suggest that the nadir of the disease may be near or may have passed. Conclusions Findings of population-age subgroup variations in LC mortality and the number of underdiagnosed cases can inform surveillance efforts, while more extensive investigations of the aetiological risk factors are needed. Impact: There was a large race, sex and age differences in trends of LC mortality in SA. These findings should inform more extensive evaluation of the aetiology and risk factors of LC in the country in order to guide control efforts.
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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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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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Chang HT, Liu CS, Chou CT, Hsieh CH, Chang CH, Chen WC, Liu SI, Hsu SS, Chen JS, Jiann BP, Huang JK, Jan CR. Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells. Hum Exp Toxicol 2016; 24:453-8. [PMID: 16235734 DOI: 10.1191/0960327105ht558oa] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 μM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate dependent Ca2+ mobilizer)-induced, but not econazoleinduced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.
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Etchin J, Montero J, Berezovskaya A, Le BT, Kentsis A, Christie AL, Conway AS, Chen WC, Reed C, Mansour MR, Ng CEL, Adamia S, Rodig SJ, Galinsky IA, Stone RM, Klebanov B, Landesman Y, Kauffman M, Shacham S, Kung AL, Wang JCY, Letai A, Look AT. Activity of a selective inhibitor of nuclear export, selinexor (KPT-330), against AML-initiating cells engrafted into immunosuppressed NSG mice. Leukemia 2016; 30:190-9. [PMID: 26202935 PMCID: PMC4994896 DOI: 10.1038/leu.2015.194] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 05/28/2015] [Accepted: 06/29/2015] [Indexed: 01/08/2023]
Abstract
Currently available combination chemotherapy for acute myeloid leukemia (AML) often fails to result in long-term remissions, emphasizing the need for novel therapeutic strategies. We reasoned that targeted inhibition of a prominent nuclear exporter, XPO1/CRM1, could eradicate self-renewing leukemia-initiating cells (LICs) whose survival depends on timely XPO1-mediated transport of specific protein and RNA cargoes. Using an immunosuppressed mouse model bearing primary patient-derived AML cells, we demonstrate that selinexor (KPT-330), an oral antagonist of XPO1 that is currently in clinical trials, has strong activity against primary AML cells while sparing normal stem and progenitor cells. Importantly, limiting dilution transplantation assays showed that this cytotoxic activity is not limited to the rapidly proliferating bulk population of leukemic cells but extends to the LICs, whose inherent drug resistance and unrestricted self-renewal capacity has been implicated in the difficulty of curing AML patients with conventional chemotherapy alone.
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Wen X, An P, Chen WC, Lv Y, Fu Q. Comparisons of sarcopenia prevalence based on different diagnostic criteria in Chinese older adults. J Nutr Health Aging 2015; 19:342-7. [PMID: 25732220 DOI: 10.1007/s12603-014-0561-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The study aimed to describe the prevalence of sarcopenia and discussed the applicability of different diagnostic criteria in Chinese older adults. 286 Chinese adults (136 men and 150 women) aged 60-88 were recruited. The prevalence of sarcopenia were calculated using different diagnostic criteria. Physical functioning was compared in sarcopenic and non-sarcopenic older adults. Compared with the standard of EWGSOP (European Working Group on Sarcopenia in Older People), the prevalence of sarcopenia was higher when the IWGS (International Working Group on Sarcopenia) standard was applied (Men: 7.4% vs. 0.8%; Women: 4.7% vs. 0%). If the AWGS (Aisa Working Group on Sarcopenia) standard was applied, the prevalence was 5.9% in men and 0.7% in women. In conclusion, the prevalence of sarcopenia in Chinese older adults ranged from 0% to around 10% when the diagnostic criteria of IGWS, EWGSOP and AGWS were applied. Further studies are still needed to investigate appropriate diagnostic criterion of sarcopenia for Chinese population.
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Parnell SR, Washington AL, Li K, Yan H, Stonaha P, Li F, Wang T, Walsh A, Chen WC, Parnell AJ, Fairclough JPA, Baxter DV, Snow WM, Pynn R. Spin echo small angle neutron scattering using a continuously pumped (3)He neutron polarisation analyser. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:023902. [PMID: 25725858 DOI: 10.1063/1.4909544] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 02/08/2015] [Indexed: 06/04/2023]
Abstract
We present a new instrument for spin echo small angle neutron scattering (SESANS) developed at the Low Energy Neutron Source at Indiana University. A description of the various instrument components is given along with the performance of these components. At the heart of the instrument are a series of resistive coils to encode the neutron trajectory into the neutron polarisation. These are shown to work well over a broad range of neutron wavelengths. Neutron polarisation analysis is accomplished using a continuously operating neutron spin filter polarised by Rb spin-exchange optical pumping of (3)He. We describe the performance of the analyser along with a study of the (3)He polarisation stability and its implications for SESANS measurements. Scattering from silica Stöber particles is investigated and agrees with samples run on similar instruments.
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Chen WC, Gentile TR, Erwin R, Watson S, Ye Q, Krycka KL, Maranville BB. 3He spin filter based polarized neutron capability at the NIST Center for Neutron Research. ACTA ACUST UNITED AC 2014. [DOI: 10.1088/1742-6596/528/1/012014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lochan A, Macaulay S, Chen WC, Mahlangu JN, Krause A. Genetic factors influencing inhibitor development in a cohort of South African haemophilia A patients. Haemophilia 2014; 20:687-92. [PMID: 24953131 DOI: 10.1111/hae.12436] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2014] [Indexed: 11/29/2022]
Abstract
A critical complication of factor VIII (FVIII) replacement therapy in Haemophilia A (HA) treatment is inhibitor development. Known genetic factors predisposing to inhibitor development include FVIII (F8) gene mutations, ethnicity, a family history of inhibitors and FVIII haplotype mismatch. The aim of this study was to characterize and correlate these genetic factors in a cohort of South African HA patients. This was a retrospective study that included 229 patients and involved the analysis of patient files, HA molecular and clinical databases and molecular analysis of the F8 gene haplotype. Of the 229 patients, 51% were of black ethnicity, 49% were white, 5% had mild HA, 4% were moderate and 91% were severe, 36% were int22 positive and 13% were inhibitor positive. Of the inhibitor positive patients, 72% were black patients. Inhibitors were reported in 27% of black int22 positive patients, 13% of black int22 negative patients, 9% of white int22 positive patients and 7% of white int22 negative. The H1 haplotype was more common in whites (75%) and H2 was more common in blacks (74%). H3 and H5 were only found in black patients and had a higher frequency of inhibitor development than H1 and H2. In this small HA cohort, black patients had a significantly higher frequency of inhibitor development and the results were indicative of an association between inhibitor development, ethnicity and haplotype.
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Chen WC, Maru DM, Abraham SC, Tan D, Raju GS. Endoscopic clip tamponade of bleeding: a novel adjunct technique for endoscopic mucosal resection. Endoscopy 2013; 45 Suppl 2 UCTN:E104-5. [PMID: 23526499 DOI: 10.1055/s-0032-1326280] [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: 12/10/2022]
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Chen WC, Weston B, Krishna SG, Gomez G, Rashid A, Katz MH, Lee JE, Raju GS. Prolonged endoscopic loop ligation for removal of gastrointestinal tumors. Endoscopy 2013; 45 Suppl 2 UCTN:E69-70. [PMID: 23526523 DOI: 10.1055/s-0032-1326075] [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: 12/10/2022]
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Lo YC, Chen WC, Huang WT, Lin YC, Liu MC, Kuo HW, Chuang JH, Yang JR, Liu MT, Wu HS, Yang CH, Chou JH, Chang FY. Surveillance of avian influenza A(H7N9) virus infection in humans and detection of the first imported human case in Taiwan, 3 April to 10 May 2013. Euro Surveill 2013. [DOI: 10.2807/ese.18.20.20479-en] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
On 3 April 2013, suspected and confirmed cases of influenza A(H7N9) virus infection became notifiable in the primary care sector in Taiwan, and detection of the virus became part of the surveillance of severe community-acquired pneumonia. On 24 April, the first imported case, reported through both surveillance systems, was confirmed in a man returning from China by sequencing from endotracheal aspirates after two negative throat swabs. Three of 139 contacts were ill and tested influenza A(H7N9)-negative.
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Lo YC, Chen WC, Huang WT, Lin YC, Liu MC, Kuo HW, Chuang JH, Yang JR, Liu MT, Wu HS, Yang CH, Chou JH, Chang FY. Surveillance of avian influenza A(H7N9) virus infection in humans and detection of the first imported human case in Taiwan, 3 April to 10 May 2013. Euro Surveill 2013; 18:20479. [PMID: 23725865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
On 3 April 2013, suspected and confirmed cases of influenza A(H7N9) virus infection became notifiable in the primary care sector in Taiwan, and detection of the virus became part of the surveillance of severe community-acquired pneumonia. On 24 April, the first imported case, reported through both surveillance systems, was confirmed in a man returning from China by sequencing from endotracheal aspirates after two negative throat swabs. Three of 139 contacts were ill and tested influenza A(H7N9)-negative.
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Thampy V, Kang J, Rodriguez-Rivera JA, Bao W, Savici AT, Hu J, Liu TJ, Qian B, Fobes D, Mao ZQ, Fu CB, Chen WC, Ye Q, Erwin RW, Gentile TR, Tesanovic Z, Broholm C. Friedel-like oscillations from interstitial iron in superconducting Fe(1+y)Te0.62Se0.38. PHYSICAL REVIEW LETTERS 2012; 108:107002. [PMID: 22463442 DOI: 10.1103/physrevlett.108.107002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Indexed: 05/31/2023]
Abstract
Using polarized and unpolarized neutron scattering, we show that interstitial Fe in superconducting Fe(1+y)Te(1-x)Se(x) induces a magnetic Friedel-like oscillation that diffracts at Q⊥=(1/2 0) and involves >50 neighboring Fe sites. The interstitial >2μ(B) moment is surrounded by compensating ferromagnetic four-spin clusters that may seed double stripe ordering in Fe(1+y)Te. A semimetallic five-band model with (1/2 1/2) Fermi surface nesting and fourfold symmetric superexchange between interstitial Fe and two in-plane nearest neighbors largely accounts for the observed diffraction.
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Ramazanoglu M, Laver M, Ratcliff W, Watson SM, Chen WC, Jackson A, Kothapalli K, Lee S, Cheong SW, Kiryukhin V. Local weak ferromagnetism in single-crystalline ferroelectric BiFeO3. PHYSICAL REVIEW LETTERS 2011; 107:207206. [PMID: 22181767 DOI: 10.1103/physrevlett.107.207206] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Indexed: 05/05/2023]
Abstract
Polarized small-angle neutron scattering studies of single-crystalline multiferroic BiFeO(3) reveal a long-wavelength spin density wave generated by ∼1° spin canting of the spins out of the rotation plane of the antiferromagnetic cycloidal order. This signifies weak ferromagnetism within mesoscopic regions of dimension 0.03 microns along [110], to several microns along [111], confirming a long-standing theoretical prediction. The average local magnetization is 0.06 μ(B)/Fe. Our results provide an indication of the intrinsic macroscopic magnetization to be expected in ferroelectric BiFeO(3) thin films under strain, where the magnetic cycloid is suppressed.
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Chen WC, Gentile TR, Fu CB, Watson S, Jones GL, McIver JW, Rich DR. Polarized3He cell development and application at NIST. ACTA ACUST UNITED AC 2011. [DOI: 10.1088/1742-6596/294/1/012003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tong X, Pierce J, Lee WT, Fleenor M, Chen WC, Jones GL, Robertson JL. Electrical heating for SEOP-based polarized3He system. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/251/1/012087] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lee WT, Tong X, Pierce J, Fleenor M, Ismaili A, Robertson JL, Chen WC, Gentile TR, Hailemariam A, Goyette R, Parizzi A, Lauter V, Klose F, Kaiser H, Lavelle C, Baxter DV, Jones GL, Wexler J, McCollum L. In-situ Polarized3He-Based Neutron Polarization Analyzer for SNS Magnetism Reflectometer. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/251/1/012086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Krycka KL, Booth RA, Hogg CR, Ijiri Y, Borchers JA, Chen WC, Watson SM, Laver M, Gentile TR, Dedon LR, Harris S, Rhyne JJ, Majetich SA. Core-shell magnetic morphology of structurally uniform magnetite nanoparticles. PHYSICAL REVIEW LETTERS 2010; 104:207203. [PMID: 20867056 DOI: 10.1103/physrevlett.104.207203] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Indexed: 05/15/2023]
Abstract
A new development in small-angle neutron scattering with polarization analysis allows us to directly extract the average spatial distributions of magnetic moments and their correlations with three-dimensional directional sensitivity in any magnetic field. Applied to a collection of spherical magnetite nanoparticles 9.0 nm in diameter, this enhanced method reveals uniformly canted, magnetically active shells in a nominally saturating field of 1.2 T. The shell thickness depends on temperature, and it disappears altogether when the external field is removed, confirming that these canted nanoparticle shells are magnetic, rather than structural, in origin.
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Cabrera I, Kenzelmann M, Lawes G, Chen Y, Chen WC, Erwin R, Gentile TR, Leão JB, Lynn JW, Rogado N, Cava RJ, Broholm C. Coupled magnetic and ferroelectric domains in multiferroic Ni3V2O8. PHYSICAL REVIEW LETTERS 2009; 103:087201. [PMID: 19792753 DOI: 10.1103/physrevlett.103.087201] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Indexed: 05/28/2023]
Abstract
Electric control of multiferroic domains is demonstrated through polarized magnetic neutron diffraction. Cooling to the cycloidal multiferroic phase of Ni3V2O8 in an electric field E causes the incommensurate Bragg reflections to become neutron spin polarizing, the sense of neutron polarization reversing with E. Quantitative analysis indicates the E-treated sample has a handedness that can be reversed by E. We further show a close association between cycloidal and ferroelectric domains through E-driven spin and electric polarization hysteresis. We suggest that a definite cycloidal handedness is achieved through magnetoelastically induced Dzyaloshinskii-Moriya interactions.
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