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Purpose In this study, we aimed to investigate the viability of utilizing CytoSorter® system to detect circulating tumor cells (CTCs) and to evaluate the diagnostic value of CTCs in breast cancer (BC). Methods A total of 366 females patients suspected of having BC and 30 healthy female volunteers were enrolled in this study. CTCs were enriched by CytoSorter®, a microfluidic‐based CTCs capturing platform. CTC detection was performed before operation or biopsy. Based on the biopsy results, patients were divided into two groups, namely patients with BC and patients with benign breast diseases (BBD). Patients with BBD and healthy volunteers were serving as controls. The correlation between CTC enumeration and patients' clinicopathological characteristics was evaluated. The receiver operating characteristic (ROC) curve was plotted to assess the diagnostic potency of CytoSorter® system in BC. Results Based on the biopsy results, 130 BC patients at different cancer stages and 236 patients with BBD were enrolled in the study. Seven subjects were dropped out from the study. CTCs were detected in 109 of 128 BC patients, in one of 29 healthy volunteers, and in 37 of 232 patients with BBD. Maximum CTC counts detected in BC patients, healthy volunteers, and patients with BBD were 8, 1, and 4, respectively. Statistical analysis showed CTCs could be used to distinguish BC patients from healthy volunteers and patients with BBD (P

Degradation modeling might be an alternative to the conventional life test in reliability assessment for high quality products. This paper develops a Bayesian approach to the step-stress accelerated degradation test. Reliability inference of the population is made based on the posterior distribution of the underlying parameters with the aid of Markov chain Monte Carlo method. Further sequential reliability inference on individual product under normal condition is also proposed. Simulation study and an illustrative example are presented to show the appropriateness of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd.

We will discuss the reliability analysis of the constant stress accelerated life tests when a parameter in the generalized gamma lifetime distribution is linear in the stress level. Statistical inference on the estimation of the underlying model parameters as well as the mean time to failure and the reliability function will be addressed on the basis of the maximum likelihood approach. Large sample theory will be derived for the goodness of fit of the data. Some simulation study and an illustrative real example will be presented to show the appropriateness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.

Myopia is becoming a significant public health problem, affecting more and more people. Studies indicate that there are two main factors, hereditary and environmental, suspected to have strong impact on myopia. Motivated by the increase in the number of people affected by this problem, this paper focuses primarily on the utilization of mathematical methods to gain further insight into their relationship with myopia. Accordingly, utilizing multidimensional longitudinal myopia data with correlation between both eyes, we develop a Bayesian structural equation model including random effects. With the aid of the MCMC method, it is capable of expressing the correlation between repeated measurements as well as the two-eye correlation and can be used to explore the relational structure among the variables in the model. We consider four observed factors, including intraocular pressure, anterior chamber depth, lens thickness, and axial length. The results indicate that the genetic effect has much greater influence on myopia than the environmental effects. Copyright © 2011 John Wiley & Sons, Ltd.

Usually, for high reliability products the production cost is high and the lifetime is much longer, which may not be observable within a limited time. In this paper, an accelerated experiment is employed in which the lifetime follows an exponential distribution with the failure rate being related to the accelerated factor exponentially. The underlying parameters are also assumed to have the exponential prior distributions. A Bayesian zero-failure reliability demonstration test is conducted to design forehand the minimum sample size and testing length subject to a certain specified reliability criterion. Probability of passing the test design as well as predictive probability for additional experiments is also derived. Sensitivity analysis of the design is investigated by a simulation study. Copyright © 2009 John Wiley & Sons, Ltd.

Human pancreatic cancers over-express the epidermal growth factor receptor (EGF-R) and all 5 known ligands of the EGF family, including EGF, transforming growth factor-alpha (TGF-alpha), amphiregulin, betacellulin and heparin-binding EGF-like growth factor (HB-EGF). The aim of the present study was to confirm the presence of EGF-R-dependent autocrine loops in a human pancreatic cancer cell line and to explore the possibility that interrupting EGF-R activation by introducing a truncated receptor abrogates pancreatic cancer cell growth. The anchorage-independent growth of PANC-1 human pancreatic cancer cells, previously shown to express TGF-alpha, was inhibited by specific anti TGF-alpha antibodies. PANC-1 cells were then either transfected with an expression plasmid encoding a kinase-deficient EGF-R cDNA (HER653) or infected with the same EGF-R cDNA using a retroviral vector. Multiple transfected and infected clones co-expressed the truncated EGF-R and endogenous EGF-R as revealed by Northern blot analysis and immunoblots. In these clones, there was a marked attenuation in EGF- and TGF-alpha-mediated EGF-R tyrosine phosphorylation and c-fos induction. There was also a significant decrease in colony formation in soft agar by comparison with control cells and a significant increase in the effect of the growth-inhibitory effect of the alkylating agent cisplatinum in these clones. Our observations indicate that dominant negative inhibition of EGF-R may have therapeutic potential in pancreatic cancer.

Estimation of the location and magnitude of the optimum has long been considered an important problem in response surface methodology. In the industrial context, prior information accumulated by the subject matter specialist bears special significance. In this paper we use the Bayesian approach to estimating the optimum in a single factor quadratic regression model. Following the Bayesian general linear model development by Broemeling the normal/gamma conjugate prior is used. Explicit formulas for the generalized maximum likehood estimates of the characteristic parameters are obtained from the joint posterior distribution.

The pleiotropic effects of the viable yellow mutation (Avy), an allele of the mouse agouti coat-color locus, include increased susceptibility to spontaneous and chemically induced tumors that affect a wide variety of tissues. As a first step toward understanding the molecular basis of this phenomenon, we established permanent fibroblast-like cell lines from newborn Avy/a and control congenic a/a mice and compared their growth characteristics in vitro. From the VY/WffC3Hf/Nctr and YS/WffCH3f/Nctr-Avy inbre strains, each of which carries the Avy allele on a congenic background, 38 clonal Avy/a and 16 clonal a/a lines were established. Regardless of inbred strain, all Avy/a cell lines exhibited a significant degree of spontaneous transformation, as assessed by focus formation in monolayer culture, whereas none of the a/a cell lines formed foci in prolonged cultures. To test whether changes in dosage of the Avy- or a-bearing chromosomes were related to these events, we analyzed each cell line with a closely linked molecular probe from the Emv-15 locus, which in the VY strain detects a restriction fragment length variant (RFLV) informative for the Avy- and a-bearing chromosomes. Most of the transformed foci maintained heterozygosity for RFLVs detected by the probe, but two of the transformants lost the a-associated RFLV, and at least one of the transformants exhibited amplification of the Avy-associated RFLV. When the transformants were analyzed with 5' sequences derived from the recently cloned agouti gene, three of eight transformants lost the a-associated RFLV, and two of the transformants showed amplification of the Avy-associated RFLV. Reverse transcriptase-polymerase chain reaction assays indicated that agouti RNA was detected in Avy/a, not a/a cell lines. Surprisingly, some of the Avy/a transformants lacked agouti RNA. These results suggest that deregulated expression of the Avy allele is required for the initiation but not for the maintenance of transformation of the Avy/a cell cultures. These cell lines may provide an in vitro culture system for studying the effect of the agouti gene on tumorigenicity as well as to potentially study other pleiotropic phenotypes.

The business model of coffee shop chains is to copy the successful environment of the first store. This study summarizes the elements and related impact factors of service quality strategies for coffee shop chains to provide a reference for future entrepreneurship. The fuzzy analytic hierarchy process method, which combines analytic hierarchy process and fuzzy set theory, allows for more accurate descriptions of the service quality evaluation process. Next, decision makers were invited to take part in the measurement of service quality for coffee shop chains. A questionnaire was used to collect quantitative data from 37 managers of coffee shop chains in Taiwan. Such findings underscore the importance of recognizing customers' varying preferences. This study tries to fill the gap by assessing the relative impact of service quality by considering various individual differences.