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1.
Anticancer Res ; 41(9): 4295-4304, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475049

RESUMO

BACKGROUND/AIM: Renal cell carcinoma (RCC) is the most common type of kidney cancer in adults. The aim of this study was to elucidate the molecular pathogenesis of sporadic RCC in Taiwan. MATERIALS AND METHODS: Fifteen patients with RCC were screened for mutations in the von Hippel-Lindau (VHL) gene by PCR and Sanger sequencing. The methylation status of promoters of 24 tumor suppressor genes by methylation sensitive multiplex ligation-dependent probe amplification analysis was also determined. RESULTS: Inactivation of the VHL gene was observed in 5 cases: three missense somatic mutations, one promoter methylation, and one small deletion. In RCCs, methylation was most frequently observed in APC (100%), CDKN2B (92.9%), CASP8, MLH1_167, and KLLN (85.7.4%), but not in FHIT, MLH1_463, DAPK1, or HIC1 (0%). CONCLUSION: In addition to VHL inactivation, promoter methylation of APC may be a universal pathognomonic event in the tumorigenesis of RCC and a candidate diagnostic and therapeutic biomarker.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Carcinoma de Células Renais/diagnóstico , Metilação de DNA , Neoplasias Renais/diagnóstico , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Detecção Precoce de Câncer , Epigênese Genética , Feminino , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Mutação de Sentido Incorreto , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Deleção de Sequência
2.
Front Psychol ; 12: 469196, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854454

RESUMO

Working speed as a latent variable reflects a respondent's efficiency to apply a specific skill, or a piece of knowledge to solve a problem. In this study, the common assumption of many response time models is relaxed in which respondents work with a constant speed across all test items. It is more likely that respondents work with different speed levels across items, in specific when these items measure different dimensions of ability in a multidimensional test. Multiple speed factors are used to model the speed process by allowing speed to vary across different domains of ability. A joint model for multidimensional abilities and multifactor speed is proposed. Real response time data are analyzed with an exploratory factor analysis as an example to uncover the complex structure of working speed. The feasibility of the proposed model is examined using simulation data. An empirical example with responses and response times is presented to illustrate the proposed model's applicability and rationality.

3.
Front Psychol ; 12: 564976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746812

RESUMO

Mixture item response theory (IRT) models include a mixture of latent subpopulations such that there are qualitative differences between subgroups but within each subpopulation the measure model based on a continuous latent variable holds. Under this modeling framework, students can be characterized by both their location on a continuous latent variable and by their latent class membership according to Students' responses. It is important to identify anchor items for constructing a common scale between latent classes beforehand under the mixture IRT framework. Then, all model parameters across latent classes can be estimated on the common scale. In the study, we proposed Q-matrix anchored mixture Rasch model (QAMRM), including a Q-matrix and the traditional mixture Rasch model. The Q-matrix in QAMRM can use class invariant items to place all model parameter estimates from different latent classes on a common scale regardless of the ability distribution. A simulation study was conducted, and it was found that the estimated parameters of the QAMRM recovered fairly well. A real dataset from the Certificate of Proficiency in English was analyzed with the QAMRM, LCDM. It was found the QAMRM outperformed the LCDM in terms of model fit indices.

4.
Appl Psychol Meas ; 45(2): 79-94, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33627915

RESUMO

Ipsative tests with multidimensional forced-choice (MFC) items have been widely used to assess career interest, values, and personality to prevent response biases. Recently, there has been a surge of interest in developing item response theory models for MFC items. In reality, a statement in an MFC item may have different utilities for different groups, which is referred to as differential statement functioning (DSF). However, few studies have been investigated methods for detecting DSF owing to the challenges related to the features of ipsative tests. In this study, three methods were adapted for DSF assessment in MFC items: equal-mean-utility (EMU), all-other-statement (AOS), and constant-statement (CS). Simulation studies were conducted to evaluate the recovery of parameters and the performance of the proposed methods. Results showed that statement parameters and DSF parameters were well recovered for all the three methods when the test did not contain any DSF statement. When the test contained one or more DSF statements, only the CS method yielded accurate estimates. With respect to DSF assessment, both the EMU method using the bootstrap standard error and the AOS method performed appropriately so long as the test did not contain any DSF statement. The CS method performed well in cases where one or more DSF-free statements were chosen as an anchor. The longer the anchor statements, the higher the power of DSF detection.

5.
Nat Biotechnol ; 38(12): 1397-1401, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33169035

RESUMO

New breeding technologies accelerate germplasm improvement and reduce the cost of goods in seed production1-3. Many such technologies could use in vivo paternal haploid induction (HI), which occurs when double fertilization precedes maternal (egg cell) genome loss. Engineering of the essential CENTROMERIC HISTONE (CENH3) gene induces paternal HI in Arabidopsis4-6. Despite conservation of CENH3 function across crops, CENH3-based HI has not been successful outside of the Arabidopsis model system7. Here we report a commercially operable paternal HI line in wheat with a ~7% HI rate, identified by screening genome-edited TaCENH3α-heteroallelic combinations. Unlike in Arabidopsis, edited alleles exhibited reduced transmission in female gametophytes, and heterozygous genotypes triggered higher HI rates than homozygous combinations. These developments might pave the way for the deployment of CENH3 HI technology in diverse crops.


Assuntos
Centrômero/metabolismo , Edição de Genes , Haploidia , Histonas/metabolismo , Triticum/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Cruzamentos Genéticos , Diploide , Histonas/química , Fenótipo
6.
J Breast Cancer ; 23(4): 430-437, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32908792

RESUMO

A 51-year-old woman presented with metachronous tumor development in bilateral breasts, thyroid, and endometrium. Additional signs and symptoms fulfilled the National Comprehensive Cancer Network criteria for Cowden syndrome. Immunohistochemistry showed loss of PTEN expression in all tumors. Single nucleotide variants, 647 germline variants (including one each in PTEN and MSH3), and 21 somatic mutations within exons were detected in all tumors after whole-exome sequencing. There were 0, 11, and 46 specific somatic mutations in bilateral breasts, thyroid, and endometrial cancers, respectively. Although PTEN mutation is key to the development of Cowden syndrome, DNA repair dysfunction might be the initial driver of mutations. Fewer mutations were required to induce initial bilateral breast carcinomas, with subsequent thyroid and endometrial carcinomas requiring more mutations for induction. When genetic screening is unavailable, breast cancer patients with clinical manifestations of Cowden syndrome must be carefully assessed for secondary malignancies, such as thyroid and endometrial carcinomas.

7.
Front Psychol ; 11: 525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32265810

RESUMO

In recent decades, cognitive diagnostic models (CDMs) have been intensively researched and applied to various educational and psychological tests. However, because existing CDMs fail to consider rater effects, the application of CDMs to constructed-response (CR) items that involve human raters is seriously limited. Given the popularity of CR items, it is desirable to develop new CDMs that are capable of describing and estimating rater effects on CR items. In this study, we developed such new CDMs within the frameworks of facets models and hierarchical rater models, using the log-linear cognitive diagnosis model as a template. The parameters of the new models were estimated with the Markov chain Monte Carlo methods implemented in the freeware JAGS. Simulations were conducted to evaluate the parameter recovery of the new models. Results showed that the parameters were recovered fairly well and the more data there were, the better the recovery. Implications and applications of the new models were illustrated with an empirical study that adopted a fine-grained checklist to assess English academic essays.

8.
Pathol Oncol Res ; 26(4): 2153-2159, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32157637

RESUMO

Wilms tumor is the most common pediatric renal malignancy. Several genetic loci have been shown to be associated with its formation. Genetic or epigenetic aberrations at WT1 and WT2 loci have been implicated in the etiology of the majority of sporadic Wilms tumors. In our previous study, most Wilms tumors tested negative for both constitutional mutations and somatic mutations in the WT1 gene. Thus, WT2 may play an important role in these tumors. In the present study, we analyzed the methylation statuses of WT2 at 11p15 using methylation sensitive multiplex ligation-dependent probe amplification in six Wilms tumors. Paternal uniparental disomy at WT2 was observed in two Wilms tumors with epithelial components due to hypermethylation at H19DMR and hypomethylation at KvDMR. Our findings highlight the benefits of testing for 11p15 epigenetic abnormalities to identify Wilms tumors with epithelial components.

9.
Psychol Assess ; 32(3): 211-226, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31647255

RESUMO

Both the dynamic goal theory of marital satisfaction and the suffocation model of marriage argue that whether people are satisfied with their marriage largely depends on their marital goals. However, the lack of a validated measure has greatly limited empirical investigations about marital goals. The current study developed the Marital Goal Scale (MGS) using Rasch modeling. We provided evidence for the validity of the scale scores and confirmed its factorial structure using confirmatory factor analysis. The MGS contains 3 subscales assessing personal growth, instrumental, and companionship goals, respectively. The functioning of each subscale with a 4-point rating scale was supported by Rasch modeling in a married sample (from Hong Kong and the United States) and an unmarried sample (from Hong Kong). The discriminant and convergent validity of the subscale scores were supported in both samples. Major assumptions of the dynamic goal theory were also examined and partially supported. The MGS provides a useful tool to support empirical research about marital goals. Future studies are encouraged to utilize this tool to further investigate the important role of marital goals in marital dynamics. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Assuntos
Objetivos , Casamento/psicologia , Satisfação Pessoal , Inquéritos e Questionários/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Fatorial , Feminino , Hong Kong , Humanos , Masculino , Casamento/estatística & dados numéricos , Pessoa de Meia-Idade , Modelos Psicológicos , Motivação , Reprodutibilidade dos Testes , Adulto Jovem
10.
Appl Psychol Meas ; 43(6): 435-448, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452553

RESUMO

Some large-scale testing requires examinees to select and answer a fixed number of items from given items (e.g., select one out of the three items). Usually, they are constructed-response items that are marked by human raters. In this examinee-selected item (ESI) design, some examinees may benefit more than others from choosing easier items to answer, and so the missing data induced by the design become missing not at random (MNAR). Although item response theory (IRT) models have recently been developed to account for MNAR data in the ESI design, they do not consider the rater effect; thus, their utility is seriously restricted. In this study, two methods are developed: the first one is a new IRT model to account for both MNAR data and rater severity simultaneously, and the second one adapts conditional maximum likelihood estimation and pairwise estimation methods to the ESI design with the rater effect. A series of simulations was then conducted to compare their performance with those of conventional IRT models that ignored MNAR data or rater severity. The results indicated a good parameter recovery for the new model. The conditional maximum likelihood estimation and pairwise estimation methods were applicable when the Rasch models fit the data, but the conventional IRT models yielded biased parameter estimates. An empirical example was given to illustrate these new initiatives.

11.
Appl Psychol Meas ; 43(6): 464-480, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452555

RESUMO

Current use of multidimensional computerized adaptive testing (MCAT) has been developed in conjunction with compensatory multidimensional item response theory (MIRT) models rather than with non-compensatory ones. In recognition of the usefulness of MCAT and the complications associated with non-compensatory data, this study aimed to develop MCAT algorithms using non-compensatory MIRT models and to evaluate their performance. For the purpose of the study, three item selection methods were adapted and compared, namely, the Fisher information method, the mutual information method, and the Kullback-Leibler information method. The results of a series of simulations showed that the Fisher information and mutual information methods performed similarly, and both outperformed the Kullback-Leibler information method. In addition, it was found that the more stringent the termination criterion and the higher the correlation between the latent traits, the higher the resulting measurement precision and test reliability. Test reliability was very similar across the dimensions, regardless of the correlation between the latent traits and termination criterion. On average, the difficulties of the administered items were found to be at a lower level than the examinees' abilities, which shed light on item bank construction for non-compensatory items.

12.
Appl Psychol Meas ; 43(3): 195-210, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31019356

RESUMO

It is commonly known that respondents exhibit different response styles when responding to Likert-type items. For example, some respondents tend to select the extreme categories (e.g., strongly disagree and strongly agree), whereas some tend to select the middle categories (e.g., disagree, neutral, and agree). Furthermore, some respondents tend to disagree with every item (e.g., strongly disagree and disagree), whereas others tend to agree with every item (e.g., agree and strongly agree). In such cases, fitting standard unfolding item response theory (IRT) models that assume no response style will yield a poor fit and biased parameter estimates. Although there have been attempts to develop dominance IRT models to accommodate the various response styles, such models are usually restricted to a specific response style and cannot be used for unfolding data. In this study, a general unfolding IRT model is proposed that can be combined with a softmax function to accommodate various response styles via scoring functions. The parameters of the new model can be estimated using Bayesian Markov chain Monte Carlo algorithms. An empirical data set is used for demonstration purposes, followed by simulation studies to assess the parameter recovery of the new model, as well as the consequences of ignoring the impact of response styles on parameter estimators by fitting standard unfolding IRT models. The results suggest the new model to exhibit good parameter recovery and seriously biased estimates when the response styles are ignored.

13.
Pathol Oncol Res ; 25(3): 1199-1206, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30671724

RESUMO

Wilms tumor, or nephroblastoma, is the most common pediatric renal malignancy. Its diagnosis is principally based on histology. Several genetic loci have been shown to be associated with Wilms tumor formation, including WT1, WT2, FWT1, FWT2, CTNNB1, WTX, and TP53. Other loci, such as 1p, 2q, 7p, 9q, 12q, 14q, 16q, 17p, and 22, have also been implicated in the etiology of Wilms tumor. The aim of this study is to elucidate the molecular pathogenesis of this tumor. In the present study, we analyzed the histological appearance and copy number aberrations using array comparative genomic hybridization of six Wilms tumors without somatic mutation in the WT1 gene. Many chromosomal aberrations on array comparative genomic hybridization analysis revealed that the genetics of Wilms tumors are extremely complex. Amplifications and deletions of large DNA fragments were observed in some samples. Amplifications of NDUFV1, ZIC2, SIX1, NR2F2, MIR1469, SOX9, JAG1, MIR6870, and GNAS were found in all six Wilms tumors. Moreover, amplifications of five genes were identified in the Wilms tumors of stromal type and amplifications of at least 10 genes were identified in the Wilms tumors of epithelial type. Our results indicated that amplifications of nine genes are the essential events in the tumorigenesis of Wilms tumor, which may inform its clinical and therapeutic management. In addition, mixed type Wilms tumor may be the heterogeneous group able to be classified using genetic results of epithelial and stromal components based on immunohistochemistry.


Assuntos
Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Hibridização Genômica Comparativa/métodos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Tumor de Wilms/genética , Tumor de Wilms/patologia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Mutação , Prognóstico
14.
Appl Psychol Meas ; 43(1): 34-50, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30573933

RESUMO

Many multilevel linear and item response theory models have been developed to account for multilevel data structures. However, most existing cognitive diagnostic models (CDMs) are unilevel in nature and become inapplicable when data have a multilevel structure. In this study, using the log-linear CDM as the item-level model, multilevel CDMs were developed based on the latent continuous variable approach and the multivariate Bernoulli distribution approach. In a series of simulations, the newly developed multilevel deterministic input, noisy, and gate (DINA) model was used as an example to evaluate the parameter recovery and consequences of ignoring the multilevel structures. The results indicated that all parameters in the new multilevel DINA were recovered fairly well by using the freeware Just Another Gibbs Sampler (JAGS) and that ignoring multilevel structures by fitting the standard unilevel DINA model resulted in poor estimates for the student-level covariates and underestimated standard errors, as well as led to poor recovery for the latent attribute profiles for individuals. An empirical example using the 2003 Trends in International Mathematics and Science Study eighth-grade mathematical test was provided.

15.
J Formos Med Assoc ; 118(1 Pt 2): 215-222, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29661488

RESUMO

BACKGROUND: Quality of life (QoL) is important for clinicians to evaluate how cancer survivors judge their sense of well-being, and WHOQOL-BREF may be a good tool for clinical use. However, at least three issues remain unresolved: (1) the psychometric properties of the WHOQOL-BREF for cancer patients are insufficient; (2) the scoring method used for WHOQOL-BREF needs to be clarify; (3) whether different types of cancer patients interpret the WHOQOL-BREF similarly. METHODS: We recruited 1000 outpatients with head/neck cancer, 1000 with colorectal cancer, 965 with liver cancer, 1438 with lung cancer and 1299 with gynecologic cancers in a medical center. Data analyses included Rasch models, confirmatory factor analysis (CFA), and Pearson correlations. RESULTS: The mean WHOQOL-BREF domain scores were between 13.34 and 14.77 among all participants. CFA supported construct validity; Rasch models revealed that almost all items were embedded in their expected domains and were interpreted similarly across five types of cancer patients; all correlation coefficients between Rasch scores and original domain scores were above 0.9. CONCLUSION: The linear relationship between Rasch scores and domain scores suggested that the current calculations for domain scores were applicable and without serious bias. Clinical practitioners may regularly collect and record the WHOQOL-BREF domain scores into electronic health records.


Assuntos
Sobreviventes de Câncer/psicologia , Pacientes Ambulatoriais , Psicometria/métodos , Qualidade de Vida/psicologia , Adulto , Idoso , Sobreviventes de Câncer/classificação , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Taiwan , Organização Mundial da Saúde
16.
Appl Psychol Meas ; 42(8): 613-629, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30559570

RESUMO

Differential item functioning (DIF) makes test scores incomparable and substantially threatens test validity. Although conventional approaches, such as the logistic regression (LR) and the Mantel-Haenszel (MH) methods, have worked well, they are vulnerable to high percentages of DIF items in a test and missing data. This study developed a simple but effective method to detect DIF using the odds ratio (OR) of two groups' responses to a studied item. The OR method uses all available information from examinees' responses, and it can eliminate the potential influence of bias in the total scores. Through a series of simulation studies in which the DIF pattern, impact, sample size (equal/unequal), purification procedure (with/without), percentages of DIF items, and proportions of missing data were manipulated, the performance of the OR method was evaluated and compared with the LR and MH methods. The results showed that the OR method without a purification procedure outperformed the LR and MH methods in controlling false positive rates and yielding high true positive rates when tests had a high percentage of DIF items favoring the same group. In addition, only the OR method was feasible when tests adopted the item matrix sampling design. The effectiveness of the OR method with an empirical example was illustrated.

17.
Front Psychol ; 9: 997, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29962994

RESUMO

Existing cognitive diagnosis models conceptualize attribute mastery status discretely as either mastery or non-mastery. This study proposes a different conceptualization of attribute mastery as a probabilistic concept, i.e., the probability of mastering a specific attribute for a person, and developing a probabilistic-input, noisy conjunctive (PINC) model, in which the probability of mastering an attribute for a person is a parameter to be estimated from data. And a higher-order version of the PINC model is used to consider the associations among attributes. The results of simulation studies revealed a good parameter recovery for the new models using the Bayesian method. The Examination for the Certificate of Proficiency in English (ECPE) data set was analyzed to illustrate the implications and applications of the proposed models. The results indicated that PINC models had better model-data fit, smaller item parameter estimates, and more refined estimates of attribute mastery.

18.
19.
Front Psychol ; 8: 1143, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28736542

RESUMO

Extreme response styles (ERS) is prevalent in Likert- or rating-type data but previous research has not well-addressed their impact on differential item functioning (DIF) assessments. This study aimed to fill in the knowledge gap and examined their influence on the performances of logistic regression (LR) approaches in DIF detections, including the ordinal logistic regression (OLR) and the logistic discriminant functional analysis (LDFA). Results indicated that both the standard OLR and LDFA yielded severely inflated false positive rates as the magnitude of the differences in ERS increased between two groups. This study proposed a class of modified LR approaches to eliminating the ERS effect on DIF assessment. These proposed modifications showed satisfactory control of false positive rates when no DIF items existed and yielded a better control of false positive rates and more accurate true positive rates under DIF conditions than the conventional LR approaches did. In conclusion, the proposed modifications are recommended in survey research when there are multiple group or cultural groups.

20.
Br J Math Stat Psychol ; 70(3): 499-524, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28390145

RESUMO

Examinee-selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non-ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two-dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non-ignorable and to determine how to apply the new model to the data collected. Two follow-up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non-ignorable missing data were mistakenly treated as ignorable.


Assuntos
Avaliação Educacional/métodos , Modelos Estatísticos , Comportamento de Escolha , Simulação por Computador , Interpretação Estatística de Dados , Avaliação Educacional/estatística & dados numéricos , Humanos , Análise de Regressão
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