276
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Ding X, Traneus E, Zhang J, Lin H, Zhai H, Rosen L, Wu H. SU-E-T-780: Use Robustness Optimization (RO) Method to Improve the Planning Efficiency for Pencil Beam Scanning Cranial Spinal Irradiation. Med Phys 2015. [DOI: 10.1118/1.4925144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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277
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Hu Y, James J, Panda A, Vargas C, Silva A, Liu W, Shen J, Ding X, Paden R, Hanson J, Wong W, Schild S, Bues M. SU-E-J-229: Magnetic Resonance Imaging of Small Fiducial Markers for Proton Beam Therapy. Med Phys 2015. [DOI: 10.1118/1.4924315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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278
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Freund D, Ding X, Wu H, Zhang J, Syh J, Syh J, Patel B, Song X. SU-E-T-636: ProteusONE Machine QA Procedure and Stabiity Study: Half Year Clinical Operation. Med Phys 2015. [DOI: 10.1118/1.4924999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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279
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Han B, Bai Z, Liu Y, You Y, Xu J, Zhou J, Zhang J, Niu C, Zhang N, He F, Ding X. Characterizations, relationship, and potential sources of outdoor and indoor particulate matter bound polycyclic aromatic hydrocarbons (PAHs) in a community of Tianjin, Northern China. INDOOR AIR 2015; 25:320-328. [PMID: 25039922 DOI: 10.1111/ina.12145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 07/17/2014] [Indexed: 06/03/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are among the most toxic air pollutants in China. However, because there are unsubstantial data on indoor and outdoor particulate PAHs, efforts in assessing inhalation exposure and cancer risk to PAHs are limited in China. This study measured 12 individual PAHs in indoor and outdoor environments at 36 homes during the non-heating period and heating period in 2009. Indoor PAH concentrations were comparable with outdoor environments in the non-heating period, but were lower in the heating period. The average indoor/outdoor ratios in both sampling periods were lower than 1, while the ratios in the non-heating period were higher than those in the heating period. Correlation analysis and coefficient of divergence also verified the difference between indoor and outdoor PAHs, which could be caused by high ventilation in the non-heating period. To support this conclusion, linear and robust regressions were used to estimate the infiltration factor to compare outdoor PAHs to indoor PAHs. The calculated infiltration factors obtained by the two models were similar in the non-heating period but varied greatly in the heating period, which may have been caused by the influence of ventilation. Potential sources were distinguished using a diagnostic ratio and a mixture of coal combustion and traffic emission, which are major sources of PAHs.
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Syh J, Patel B, Syh J, Song X, Freund D, Ding X, Wu H. SU-E-I-56: Diagnostic Lead Apron Radiation Exposure Comparison Between Manufacture-Stated and Measurements. Med Phys 2015. [DOI: 10.1118/1.4924053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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281
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Syh J, Ding X, Rosen L, Wu H. SU-E-T-280: Dose Evaluation in Using CT Density Versus Relative Stopping Power for Pencil Beam Planning and Treating IROC Proton Phantom. Med Phys 2015. [DOI: 10.1118/1.4924642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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282
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Patel B, Syh J, Ding X, Syh J, Song X, Freund D, Wu H. SU-E-T-662: Quick and Efficient Daily QA for Compact PBS Proton Therapy Machine. Med Phys 2015. [DOI: 10.1118/1.4925025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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283
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Fuentes CL, Geismer D, Christiaens M, Vermeren X, Ding X. SU-E-E-12: Validation of the Implementation of Different CT Scanners in Proton Treatment Planning. Med Phys 2015. [DOI: 10.1118/1.4923934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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284
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Zhang J, Durci M, Wu H, Rosen L, Ding X. SU-E-T-143: Automatic PBS Treatment Planning for Prostate Cancer. Med Phys 2015. [DOI: 10.1118/1.4924505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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285
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Li TX, Ding X, Sui X, Tian LL, Zhang Y, Hu JY, Yang XD. Sustained Release of Protein Particle Encapsulated in Bead-on-String Electrospun Nanofibers. J MACROMOL SCI B 2015. [DOI: 10.1080/00222348.2015.1051210] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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286
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Ma Y, Ding X, Qanbari S, Weigend S, Zhang Q, Simianer H. Properties of different selection signature statistics and a new strategy for combining them. Heredity (Edinb) 2015; 115:426-36. [PMID: 25990878 PMCID: PMC4611237 DOI: 10.1038/hdy.2015.42] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 03/25/2015] [Accepted: 03/31/2015] [Indexed: 12/11/2022] Open
Abstract
Identifying signatures of recent or ongoing selection is of high relevance in livestock population genomics. From a statistical perspective, determining a proper testing procedure and combining various test statistics is challenging. On the basis of extensive simulations in this study, we discuss the statistical properties of eight different established selection signature statistics. In the considered scenario, we show that a reasonable power to detect selection signatures is achieved with high marker density (>1 SNP/kb) as obtained from sequencing, while rather small sample sizes (~15 diploid individuals) appear to be sufficient. Most selection signature statistics such as composite likelihood ratio and cross population extended haplotype homozogysity have the highest power when fixation of the selected allele is reached, while integrated haplotype score has the highest power when selection is ongoing. We suggest a novel strategy, called de-correlated composite of multiple signals (DCMS) to combine different statistics for detecting selection signatures while accounting for the correlation between the different selection signature statistics. When examined with simulated data, DCMS consistently has a higher power than most of the single statistics and shows a reliable positional resolution. We illustrate the new statistic to the established selective sweep around the lactase gene in human HapMap data providing further evidence of the reliability of this new statistic. Then, we apply it to scan selection signatures in two chicken samples with diverse skin color. Our analysis suggests that a set of well-known genes such as BCO2, MC1R, ASIP and TYR were involved in the divergent selection for this trait.
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287
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Ding X, Yue JR, Yang M, Hao QK, Xiao HY, Chen T, Gao LY, Dong BR. Association between the rs189037 single nucleotide polymorphism in the ATM gene promoter and cognitive impairment. GENETICS AND MOLECULAR RESEARCH 2015; 14:4584-92. [PMID: 25966232 DOI: 10.4238/2015.may.4.17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The aim of this study was to explore the existence of a relationship between the rs189037 single nucleotide polymorphism (SNP) of the ataxia telangiectasia mutated (ATM) gene and cognitive impairment in the elderly (aged 60 years and above). In a cohort, 505 residents of Suinung City were consecutively recruited and their cognitive function was measured using a 30-point Mini-Mental State Examination (MMSE). The subjects were divided into cognitive impairment group and control group on the basis of MMSE scores. Presence of the rs189037 SNP variant was examined using polymerase chain reaction-restriction fragment length polymorphism. The prevalence rates of cognitive impairment were 32.7% in the whole sample. The genotype frequencies of the rs189037 polymorphism were 33.5% (CC), 50.7% (CT), and 15.8% (TT); the C and T allele frequencies were 58.8 and 41.2%, respectively. No significant differences in the frequency distributions of the CC, CT and TT genotypes were observed between cognitively impaired and control groups. We found that the rs189037 SNP was not directly correlated with cognitive impairment among the elderly Chinese Han population.
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Ding C, Xue W, Tian P, Ding X, Pan X, Xiang H, Tian X, Li Y, Zheng J. Which is more suitable for kidney transplantation at the early post-transplantation phase in China - low dosing or standard dosing of enteric-coated mycophenolate sodium? Int J Clin Pract 2015:10-6. [PMID: 24673714 DOI: 10.1111/ijcp.12401] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
AIMS To investigate the pharmacokinetics of enteric-coated mycophenolate sodium (EC-MPS) and the clinical outcome in kidney transplant recipients in the early post-transplantation phase. Then explain which regimen is more suitable for Chinese renal transplant recipients. METHODOLOGY In total, 60 de novo kidney transplant recipients treated with tacrolimus and steroids were randomised to receive EC-MPS at standard dose (SD; 1440 mg/day; n = 28) or low dose (LD; 1080 mg/day; n = 32). Efficacy parameters, safety and tolerability were assessed over a 6-month study period. Full mycophenolic acid (MPA) areas under the curve (AUCs) were completed on days 3 and 5, whereas a three-point limited sampling strategy (LSS) was utilised for MPA AUC assessments at 2 weeks and months 1, 3 and 6 (the LSS for three-time-point MPA AUC 0-12 h (mg h/l) = 15.99 + 0.87C1 h + 0.68C2 h + 7.85C4 h ; r(2) = 0.8670. RESULTS The mean AUC levels at day 3 and day 5 in the SD group were significantly higher than in the LD group (57.4 mg·h/l vs. 38.2 mg·h/l and 59.3 mg·h/l vs. 44.8 mg·h/l, respectively, p < 0.01). There was a trend for fewer clinically diagnosed acute rejections in the SD group vs. the LD group at 6 months (7.1% vs. 12.5%). This trend was also present when acute rejection was analysed as biopsy-proven cases. There were significantly more acute rejections (all definitions) in patients with MPA AUC levels < 30 mg·h/l compared with those with MPA AUC levels ≥ 30 mg·h/l within 6 months (p < 0.05). Renal function, incidence of infection and haematological disorders were not significantly different in either study group. CONCLUSIONS Early adequate MPA exposure in renal transplant recipients can be achieved with a higher starting dose. In addition, a SD regimen was as well-tolerated as a LD regimen. Furthermore, early adequate MPA exposure significantly lowered the rate of acute rejection without compromising safety and tolerability.
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289
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Ding X, Dai R, Zhao Z, Wang Z, Sun Z, Zhang Z, Ding Z. Irreversible temperature quenching and antiquenching of photoluminescence of ZnS/CdS:Mn/ZnS quantum well quantum dots. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.02.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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290
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Hu D, Wang X, Cao R, Ding X. Effects of down-regulated steroidogenic factor-1 on ACTH and potassium chloride-induced steroid synthesis in H295R cells. Cell Mol Biol (Noisy-le-grand) 2015; 61:51-55. [PMID: 25817346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/20/2015] [Indexed: 06/04/2023]
Abstract
The prevalence of adrenal diseases in the cortex is more common than that in the medulla in the form of hormone disorder or neoplasm. Steroidogenic factor—1 (SF—1) is important in regulating aldosterone synthase (CYP11B2) and cortisol synthase (CYP11B1). SF—1 is increased in aldosterone—producing adenoma (APA) and cortisol—producing adenoma (CPA). Overexpression of SF—1 has been extensively studied, but the available in—depth information regarding the effects of downregulated SF—1 on CYP11B2/CYP11B1 and their regulators is limited. In this paper, we attempted to investigate the effects of downregulated SF—1 on aldosterone to adrenocorticotropic hormone (ACTH) and potassium chloride (KCl) stimulation and those on cortisol to ACTH stimulation through RNA interference in acute and chronic phases. Downregulated SF—1 decreased the sensitivity of aldosterone to ACTH/KCl and that of cortisol to ACTH stimulation. This study provides new insights into the influence of SF—1 on adrenocortical diseases by considering the effects of SF—1 on regulation.
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291
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Ray DS, Wiemann AH, Patel PB, Ding X, Kryscio RJ, Miller CS. Estimation of the rate of tooth wear in permanent incisors: a cross-sectional digital radiographic study. J Oral Rehabil 2015; 42:460-6. [PMID: 25756187 DOI: 10.1111/joor.12288] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2015] [Indexed: 11/30/2022]
Abstract
This study used conventional digital radiography to estimate the rate of tooth wear (TW) of maxillary and mandibular central incisors based on a cross-sectional study design. The crown length of 1239 permanent maxillary and mandibular central incisors from 346 persons (age groups: 10, 25, 40, 55 and 70 years ± 3) were measured by three calibrated dentists. Study teeth were intact incisally, had clearly visible incisal edges and cementoenamel junctions and had natural tooth antagonists. Measures were based on digital radiographic images (N = 666) archived in MiPACS within the electronic health record (axiUm(®)) from the College of Dentistry patient database. Incisor crown length decreased at a linear rate in both arches over the 60 years represented by the age groups. The average crown length for maxillary incisors in the youngest age group was 11.94 mm, which decreased by an average of 1.01 mm by median age 70. For mandibular incisors, the average crown length in the youngest age group was 9.58 mm, which decreased by an average of 1.46 mm in the oldest age group. Males and females showed similar rates of TW. Regardless of age, females demonstrated smaller mean crown height for maxillary incisors than males (P < 0.0001). Measures by the examiners demonstrated good agreement, with an interclass correlation coefficient of 0.869 and an average intra-examiner correlation of 99.5%, based on repeated measurements (n = 100). TW was estimated to average 1.01 mm for maxillary central incisors and 1.46 mm for mandibular central incisors by age 70 years.
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292
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Ding X. P326 ARM in breast cancer with enlarged lymph node: a Chinese single center experience. Breast 2015. [DOI: 10.1016/s0960-9776(15)70356-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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293
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Gao L, Ding X, Xie D, Yang M, Dong B. G-395A polymorphism in the promoter region of the KLOTHO gene and hypertension among elderly (90 years and older) Chinese individuals. GENETICS AND MOLECULAR RESEARCH 2015; 14:15444-52. [DOI: 10.4238/2015.november.30.22] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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294
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Ding X, Li L, Lv Y, Xu F, Kuang H, Wang S. Effects of Fermented Sesame Meal on the Performance, Serum Biochemical Parameters and Intestinal Morphology of Ducks. ANIM NUTR FEED TECHN 2015. [DOI: 10.5958/0974-181x.2015.00036.0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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295
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Yuan M, Yang Y, Yu S, Hu A, Lu L, Ma J, Ding X, Li J. Posterior Pole Retinal Abnormalities in Mild Asymptomatic FEVR. Invest Ophthalmol Vis Sci 2014; 56:458-63. [DOI: 10.1167/iovs.14-15821] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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296
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Liu H, Chang Q, Feng W, Zhang B, Wu T, Li N, Yao F, Ding X, Chu Z. Domain dissection of AvrRxo1 for suppressor, avirulence and cytotoxicity functions. PLoS One 2014; 9:e113875. [PMID: 25437277 PMCID: PMC4250038 DOI: 10.1371/journal.pone.0113875] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 11/01/2014] [Indexed: 12/27/2022] Open
Abstract
AvrRxo1, a type III effector from Xanthomonas oryzae pv. oryzicola (Xoc) which causes bacterial leaf streak (BLS) in rice, can be recognised by non-host resistance protein Rxo1. It triggers a hypersensitive response (HR) in maize. Little is known regarding the virulence function of AvrRxo1. In this study, we determined that AvrRxo1 is able to suppress the HR caused by the non-host resistance recognition of Xanthomonas oryzae pv. oryzae (Xoo) by Nicotiana benthamiana. It is toxic, inducing cell death from transient expression in N. benthamiana, as well as in yeast. Among the four AvrRxo1 alleles from different Xoc strains, we concluded that the toxicity is abolished by a single amino acid substitution at residue 344 in two AvrRxo1 alleles. A series of truncations from the carboxyl terminus (C-terminus) indicate that the complete C-terminus of AvrRxo1 plays an essential role as a suppressor or cytotoxic protein. The C-terminus was also required for the avirulence function, but the last two residues were not necessary. The first 52 amino acids of N-terminus are unessential for toxicity. Point mutagenesis experiments indicate that the ATP/GTP binding site motif A is required for all three functions of AvrRxo1, and NLS is required for both the avirulence and the suppression of non-host resistance. The putative thiol protease site is only required for the cytotoxicity function. These results determine that AvrRxo1 plays a role in the complex interaction with host proteins after delivery into plant cells.
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He S, Wang S, Fu W, Ding X, Zhang Q. Imputation of missing genotypes from low- to high-density SNP panel in different population designs. Anim Genet 2014; 46:1-7. [PMID: 25431355 DOI: 10.1111/age.12236] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2014] [Indexed: 01/28/2023]
Abstract
Imputation of missing genotypes, in particular from low density to high density, is an important issue in genomic selection and genome-wide association studies. Given the marker densities, the most important factors affecting imputation accuracy are the size of the reference population and the relationship between individuals in the reference (genotyped with high-density panel) and study (genotyped with low-density panel) populations. In this study, we investigated the imputation accuracies when the reference population (genotyped with Illumina BovineSNP50 SNP panel) contained sires, halfsibs, or both sires and halfsibs of the individuals in the study population (genotyped with Illumina BovineLD SNP panel) using three imputation programs (fimpute v2.2, findhap v2, and beagle v3.3.2). Two criteria, correlation between true and imputed genotypes and missing rate after imputation, were used to evaluate the performance of the three programs in different scenarios. Our results showed that fimpute performed the best in all cases, with correlations from 0.921 to 0.978 when imputing from sires to their daughters or between halfsibs. In general, the accuracies of imputing between halfsibs or from sires to their daughters were higher than were those imputing between non-halfsibs or from sires to non-daughters. Including both sires and halfsibs in the reference population did not improve the imputation performance in comparison with when only including halfsibs in the reference population for all the three programs.
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298
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Lei L, Li T, Ding X, Ma W, Zhu X, Atik A, Hu Y, Tang S. Gas tamponade combined with laser photocoagulation therapy for congenital optic disc pit maculopathy. Eye (Lond) 2014; 29:106-14. [PMID: 25323852 DOI: 10.1038/eye.2014.245] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/15/2014] [Indexed: 12/24/2022] Open
Abstract
PURPOSE To evaluate the long-term clinical efficacy and safety of gas tamponade combined with laser photocoagulation for optic disc pit maculopathy. METHODS Seven consecutive patients with unilateral maculopathy associated with optic disc pit and one patient with bilateral optic disc pit maculopathy were given octafluoropropane (C3F8) tamponade combined with focal laser photocoagulation treatment. Patients were followed up for 21-62 months after treatment. Main outcomes were determined by optical coherence tomography (OCT) and best-corrected visual acuity (BCVA). RESULTS Treatment with C3F8 tamponade followed by laser photocoagulation in ODP maculopathy patients resulted in resolution of sub-retinal and/or intra-retinal fluid in six out of eight patients. The remaining two patients had significant reduction in fluid, as determined by OCT, and funduscopy, as well as an improvement in anatomical architecture. Visual acuity improved obviously in seven eyes and remained stable in two eyes. Central visual field loss after photocoagulation was not clinically appreciable by visual field examination. No post-operative complications of maculopathy occurred during the follow-up period. CONCLUSIONS Although repeated treatment was needed in some patients, C3F8 tamponade combined with laser photocoagulation is still a simple, effective, minimally invasive, and economic therapy for optic disc pit maculopathy.
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299
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Ding X, Li F, McKnight J, Schmidt C, Strooisma K, Shimizu H, Faber K, Ware JA, Dean B. A supported liquid extraction-LC-MS/MS method for determination of GDC-0980 (Apitolisib), a dual small-molecule inhibitor of class 1A phosphoinositide 3-kinase and mammalian target of rapamycin, in human plasma. J Pharm Biomed Anal 2014; 100:150-156. [PMID: 25165011 DOI: 10.1016/j.jpba.2014.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 07/30/2014] [Accepted: 08/02/2014] [Indexed: 12/31/2022]
Abstract
A liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for the determination of GDC-0980 (Apitolisib) concentrations in human plasma has been developed and validated to support clinical development. Supported liquid extraction (SLE) was used to extract plasma samples (80μL) and the resulting samples were analyzed using reverse-phase chromatography and mass spectrometry coupled with a turbo-ionspray interface. The mass analysis of GDC-0980 was performed using multiple reaction monitoring (MRM) transitions in positive ionization mode. The method was validated over the calibration curve range 0.0500-25.0ng/mL using linear regression and 1/x(2) weighting. Within-run relative standard deviation (%RSD) ranged from 0.4 to 3.9%, while the between-run %RSD varied from 1.1 to 1.5% for QCs. The accuracy ranged from 96.1% to 106.7% of nominal for within-run and 96.7-106.7% of nominal for between-run at all concentrations including the LLOQ quality control at 0.0500ng/mL. Extraction recovery of GDC-0980 was between 72.4% and 75.5%. Stability of GDC-0980 was established in human plasma for 547 days at -20°C and -70°C and established in reconstituted sample extracts for 146h when stored at 2-8°C. Stable-labeled internal standard was used to minimize matrix effects. Mean pharmacokinetic parameters determined using this method for the day 1 control group in a phase I trial were: Cmax=11.1ng/mL, AUC0-inf=108ngh/mL, and T1/2=13.1h.
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Chen B, Yu S, Ding X, Jing C, Xia L, Wang M, Matro E, Rehman F, Niu Y, Li G, Chang C. The role of testicular nuclear receptor 4 in chemo-resistance of docetaxel in castration-resistant prostate cancer. Cancer Gene Ther 2014; 21:411-5. [PMID: 25104727 DOI: 10.1038/cgt.2014.41] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 07/09/2014] [Accepted: 07/10/2014] [Indexed: 01/08/2023]
Abstract
Docetaxel-based therapy is one of the first-line options for castration-resistant prostate cancer (CRPC). However, a large proportion of CRPC patients show different extents of docetaxel resistance. The current study aims to investigate the role of testicular nuclear receptor 4 (TR4) in docetaxel resistance in CRPC. TR4 expression level in prostate biopsy samples from CRPC patients treated with docetaxel was measured by immunohistochemistry (IHC). Alternation of TR4 expression in prostate cancer (PCa) cell line PC3 was applied to find out the influence of TR4 on half-maximal inhibitory concentration (IC50), cell viability and cell apoptosis. Patients who failed to achieve prostate-specific antigen (PSA) response (<50% PSA reduction from baseline) after docetaxel-based chemotherapy had a comparatively higher TR4 expression than those who achieved PSA response (⩾50% PSA reduction from baseline). Knocking down TR4 in PC3 cells led to a lower IC50 dose, poorer cell viability and more cell apoptosis when treated with docetaxel, whereas overexpression of TR4 in PC3 led to a higher IC50 dose, better cell viability and less cell apoptosis. TR4 enhances the chemo-resistance of docetaxel in CRPC. It may serve as a biomarker to determine the prognosis of docetaxel-based therapy and as a potential therapy target to combine with docetaxel to better suppress CRPC.
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