AIM:To investigate M2 isoform of pyruvate kinase(PKM2) expression in gastric cancers and evaluate its potential as a prognostic biomarker and an anticancer target.METHODS:All tissue samples were derived from gastric c...AIM:To investigate M2 isoform of pyruvate kinase(PKM2) expression in gastric cancers and evaluate its potential as a prognostic biomarker and an anticancer target.METHODS:All tissue samples were derived from gastric cancer patients underwent curative gastrectomy as a primary treatment.Clinical and pathological information were obtained from the medical records.Gene expression microarray data from 60 cancer and 19 noncancer gastric tissues were analyzed to evaluate the expression level of PKM2 mRNA.Tissue microarrays were constructed from 368 gastric cancer patients.Immunohistochemistry was used to measure PKM2 expression and PKM2 positivity of cancer was determined by proportion of PKM2-positive tumor cells and staining intensity.Association between PKM2 expression and the clinicopathological factors was evaluated and the correlation between PKM2 and cancer prognosis was evaluated.RESULTS:PKM2 mRNA levels were increased more than 2-fold in primary gastric cancers compared to adjacent normal tissues from the same patients(log transformed expression level:7.6 ± 0.65 vs 6.3 ± 0.51,P < 0.001).Moreover,differentiated type cancers had significantly higher PKM2 mRNA compared to undifferentiated type cancers(log transformed expression level:7.8 ± 0.70 vs 6.7 ± 0.71,P < 0.001).PKM2 protein was mainly localized in the cytoplasm of primary cancer cells and detected in 144 of 368(39.1%) human gastric cancer cases.PKM2 expression was not related with stage(P = 0.811),but strongly correlated with gastric cancer differentiation(P < 0.001).Differentiated type cancers expressed more PKM2 protein than did the undifferentiated ones.Well differentiated adenocarcinoma showed 63.6% PKM2-positive cells;in contrast,signet-ring cell cancers showed only 17.7% PKM2-positive cells.Importantly,PKM2 expression was correlated with shorter overall survival(P < 0.05) independent of stage only in signet-ring cell cancers.CONCLUSION:PKM2 expression might be an adverse prognostic factor for signet-ring cell carcinomas.Its function and potential as a prognostic marker should be further verified in gastric cancer.展开更多
The distributions of local velocity and local phase holdup along the radial direction of pipes are complicated because of gravity differentiation,and the distribution of fluid velocity fi eld changes along the gravity...The distributions of local velocity and local phase holdup along the radial direction of pipes are complicated because of gravity differentiation,and the distribution of fluid velocity fi eld changes along the gravity direction in horizontal wells.Therefore,measuring the mixture flow and water holdup is difficult,resulting in poor interpretation accuracy of the production logging output profile.In this paper,oil–water two-phase flow dynamic simulation logging experiments in horizontal oil–water two-phase fl ow simulation wells were conducted using the Multiple Array Production Suite,which comprises a capacitance array tool(CAT)and a spinner array tool(SAT),and then the response characteristics of SAT and CAT in diff erent fl ow rates and water cut production conditions were studied.According to the response characteristics of CAT in diff erent water holdup ranges,interpolation imaging along the wellbore section determines the water holdup distribution,and then,the oil–water two-phase velocity fi eld in the fl ow section was reconstructed on the basis of the fl ow section water holdup distribution and the logging value of SAT and combined with the rheological equation of viscous fl uid,and the calculation method of the oil–water partial phase fl ow rate in the fl ow section was proposed.This new approach was applied in the experiment data calculations,and the results are basically consistent with the experimental data.The total fl ow rate and water holdup from the calculation are in agreement with the set values in the experiment,suggesting that the method has high accuracy.展开更多
Orthogonal arrays (OAs), mixed level or fixed level (asymmetric or symmetric), are useful in the design of various experiments. They are also a fundamental tool in the construction of various combinatorial configurati...Orthogonal arrays (OAs), mixed level or fixed level (asymmetric or symmetric), are useful in the design of various experiments. They are also a fundamental tool in the construction of various combinatorial configurations. In this paper, we establish a general "expansive replacement method" for constructing mixedlevel OAs of an arbitrary strength. As a consequence, a positive answer to the question about orthogonal arrays posed by Hedayat, Sloane and Stufken is given. Some series of mixed level OAs of strength ≥3 are produced.展开更多
Latin hypercube design and uniform design are two kinds of most popular space-filling designs for computer experiments. The fact that the run size equals the number of factor levels in a Latin hypercube design makes i...Latin hypercube design and uniform design are two kinds of most popular space-filling designs for computer experiments. The fact that the run size equals the number of factor levels in a Latin hypercube design makes it difficult to be orthogonal. While for a uniform design, it usually has good space-filling properties, but does not necessarily have small or zero correlations between factors. In this paper, we construct a class of column-orthogonal and nearly column-orthogonal designs for computer experiments by rotating groups of factors of orthogonal arrays, which supplement the designs for computer experiments in terms of various run sizes and numbers of factor levels and are flexible in accommodating various combinations of factors with different numbers of levels. The resulting column-orthogonal designs not only have uniformly spaced levels for each factor but also have uncorrelated estimates of the linear effects in first order models. Further, they are 3-orthogonal if the corresponding orthogonal arrays have strength equal to or greater than three. Along with a large factor-to-run ratio, these newly constructed designs are economical and suitable for screening factors for physical experiments.展开更多
基金Supported by Faculty Research Grant of Yonsei University College of Medicine for 2011,6-2011-0113,6-2011-0146A Faculty Research Grant of Department of Internal Medicine,Yonsei University College of Medicine for 2010Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education,Science and Technology,No. 2010-0024248
文摘AIM:To investigate M2 isoform of pyruvate kinase(PKM2) expression in gastric cancers and evaluate its potential as a prognostic biomarker and an anticancer target.METHODS:All tissue samples were derived from gastric cancer patients underwent curative gastrectomy as a primary treatment.Clinical and pathological information were obtained from the medical records.Gene expression microarray data from 60 cancer and 19 noncancer gastric tissues were analyzed to evaluate the expression level of PKM2 mRNA.Tissue microarrays were constructed from 368 gastric cancer patients.Immunohistochemistry was used to measure PKM2 expression and PKM2 positivity of cancer was determined by proportion of PKM2-positive tumor cells and staining intensity.Association between PKM2 expression and the clinicopathological factors was evaluated and the correlation between PKM2 and cancer prognosis was evaluated.RESULTS:PKM2 mRNA levels were increased more than 2-fold in primary gastric cancers compared to adjacent normal tissues from the same patients(log transformed expression level:7.6 ± 0.65 vs 6.3 ± 0.51,P < 0.001).Moreover,differentiated type cancers had significantly higher PKM2 mRNA compared to undifferentiated type cancers(log transformed expression level:7.8 ± 0.70 vs 6.7 ± 0.71,P < 0.001).PKM2 protein was mainly localized in the cytoplasm of primary cancer cells and detected in 144 of 368(39.1%) human gastric cancer cases.PKM2 expression was not related with stage(P = 0.811),but strongly correlated with gastric cancer differentiation(P < 0.001).Differentiated type cancers expressed more PKM2 protein than did the undifferentiated ones.Well differentiated adenocarcinoma showed 63.6% PKM2-positive cells;in contrast,signet-ring cell cancers showed only 17.7% PKM2-positive cells.Importantly,PKM2 expression was correlated with shorter overall survival(P < 0.05) independent of stage only in signet-ring cell cancers.CONCLUSION:PKM2 expression might be an adverse prognostic factor for signet-ring cell carcinomas.Its function and potential as a prognostic marker should be further verified in gastric cancer.
基金supported by National Natural Science Foundation of China(41474115,42174155)Open Fund of Key Laboratory of Exploration Technologies for Oil and Gas Resources(Yangtze University)Ministry of Education of China(No K2018-02)。
文摘The distributions of local velocity and local phase holdup along the radial direction of pipes are complicated because of gravity differentiation,and the distribution of fluid velocity fi eld changes along the gravity direction in horizontal wells.Therefore,measuring the mixture flow and water holdup is difficult,resulting in poor interpretation accuracy of the production logging output profile.In this paper,oil–water two-phase flow dynamic simulation logging experiments in horizontal oil–water two-phase fl ow simulation wells were conducted using the Multiple Array Production Suite,which comprises a capacitance array tool(CAT)and a spinner array tool(SAT),and then the response characteristics of SAT and CAT in diff erent fl ow rates and water cut production conditions were studied.According to the response characteristics of CAT in diff erent water holdup ranges,interpolation imaging along the wellbore section determines the water holdup distribution,and then,the oil–water two-phase velocity fi eld in the fl ow section was reconstructed on the basis of the fl ow section water holdup distribution and the logging value of SAT and combined with the rheological equation of viscous fl uid,and the calculation method of the oil–water partial phase fl ow rate in the fl ow section was proposed.This new approach was applied in the experiment data calculations,and the results are basically consistent with the experimental data.The total fl ow rate and water holdup from the calculation are in agreement with the set values in the experiment,suggesting that the method has high accuracy.
基金supported by National Natural Science Foundation of China (Grant Nos.11271280 and 10831002)
文摘Orthogonal arrays (OAs), mixed level or fixed level (asymmetric or symmetric), are useful in the design of various experiments. They are also a fundamental tool in the construction of various combinatorial configurations. In this paper, we establish a general "expansive replacement method" for constructing mixedlevel OAs of an arbitrary strength. As a consequence, a positive answer to the question about orthogonal arrays posed by Hedayat, Sloane and Stufken is given. Some series of mixed level OAs of strength ≥3 are produced.
基金supported by the Program for New Century Excellent Talents in Universityof China (Grant No. NCET-07-0454)National Natural Science Foundation of China (Grant No. 10971107)the Fundamental Research Funds for the Central Universities (Grant No. 10QNJJ003)
文摘Latin hypercube design and uniform design are two kinds of most popular space-filling designs for computer experiments. The fact that the run size equals the number of factor levels in a Latin hypercube design makes it difficult to be orthogonal. While for a uniform design, it usually has good space-filling properties, but does not necessarily have small or zero correlations between factors. In this paper, we construct a class of column-orthogonal and nearly column-orthogonal designs for computer experiments by rotating groups of factors of orthogonal arrays, which supplement the designs for computer experiments in terms of various run sizes and numbers of factor levels and are flexible in accommodating various combinations of factors with different numbers of levels. The resulting column-orthogonal designs not only have uniformly spaced levels for each factor but also have uncorrelated estimates of the linear effects in first order models. Further, they are 3-orthogonal if the corresponding orthogonal arrays have strength equal to or greater than three. Along with a large factor-to-run ratio, these newly constructed designs are economical and suitable for screening factors for physical experiments.
