The phyA^m gene encoding acid phytase and optimized neutral phytase phyCs gene were inserted into expression vector pPIC9K in correct orientation and transformed into Pichiapastoris in order to expand the pH profile o...The phyA^m gene encoding acid phytase and optimized neutral phytase phyCs gene were inserted into expression vector pPIC9K in correct orientation and transformed into Pichiapastoris in order to expand the pH profile ofphytase and decrease the cost of production. The fusion phytase phyA^m-phyCs gene was successfully overexpressed in P. pastoris as an active and extracellular phytase. The yield of total extracellular fusion phytase activity is (25.4±0.53) U/ml at the flask scale and (159.1±2.92) U/ml for high cell-density fermentation, respectively. Purified fusion phytase exhibits an optimal temperature at 55 ℃ and an optimal pH at 5.5-6.0 and its relative activity remains at a relatively high level of above 70% in the range ofpH 2.0 to 7.0. About 51% to 63% of its original activity remains after incubation at 75 ℃ to 95 ℃ for 10 min. Due to heavy glycosylation, the expressed fusion phytase shows a broad and diffuse band in SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). After deglycosylation by endoglycosidase H (EndoHf), the enzyme has an apparent molecular size of 95 kDa. The characterization of the fusion phytase was compared with those ofphyCs andphyA^m.展开更多
AIM: To evaluate the influence of preoperative FOLFOX chemotherapy on CCL20/CCR6 expression in liver metastases of stage IV colorectal cancer (CRC) patients.(/7 = 53) and in patients who did not receive FOLFOX ch...AIM: To evaluate the influence of preoperative FOLFOX chemotherapy on CCL20/CCR6 expression in liver metastases of stage IV colorectal cancer (CRC) patients.(/7 = 53) and in patients who did not receive FOLFOX chemotherapy prior to liver surgery (n = 29). RESULTS: Of the 53 patients who received FOLFOX, time to liver surgery was n〈 1 mo in 14 patients, 〈 1 year in 22 patients and 〉 1 year in 17 patients, respectively. In addition, we investigated the proliferation rate of CRC cells in liver metastases in the different patient groups. Both CCL20 and CCR6 mRNA and protein ex- pression levels were significantly increased in patients who received preoperative FOLFOX chemotherapy ~〈 12 mo before liver surgery (P 〈 0.001) in comparison to patients who did not undergo FOLFOX treatment. Further, proliferation of CRLM cells as measured by Ki-67 was increased in patients who underwent FOLFOX treat- ment. CCL20 and CCR6 expression levels were significantly increased in CRLM patients who had undergone preoperative FOLFOX chemotherapy. CONCLUSION: This chemokine/receptor up-regulation could lead to increased proliferation/migration through an autocrine mechanism which might be used by surviving metastatic cells to escape cell death caused by FOLFOX.展开更多
(m, k)-firm real-time or weakly hard real-time (WHRT) guarantee is becoming attractive as it closes the gap between hard and soft (or probabilistic) real-time guarantee, and enables finer granularity of real-time QoS ...(m, k)-firm real-time or weakly hard real-time (WHRT) guarantee is becoming attractive as it closes the gap between hard and soft (or probabilistic) real-time guarantee, and enables finer granularity of real-time QoS through adjusting m and k. For multiple streams with (m, k)-firm constraint sharing a single server, an on-line priority assignment policy based on the most recent k-length history of each stream called distance based priority (DBP) has been proposed to assign priority.In case of priority equality among these head-of-queue instances, Earliest Deadline First (EDF) is used. Under the context of WHRT schedule theory, DBP is the most popular, gets much attention and has many applications due to its straightforward priority assignment policy and easy implementation. However, DBP combined with EDF cannot always provide good performance, mainly because the initial DBP does not underline the rich information on deadline met/missed distribution,specially streams in various failure states which will travel different distances to restore success states. Considering how to effectively restore the success state of each individual stream from a failure state, an integrated DBP utilizing deadline met/missed distribution is proposed in this paper. Simulation results validated the performance improvement of this pro-posal.展开更多
Objective. To clone complete EcoRII restriction endonuclease gene (ecoRIIR) and methyltransferase gene (ecoRIIM) in one vector and to analyze the coordinating expression of this whole R M system.Methods. Unidirectiona...Objective. To clone complete EcoRII restriction endonuclease gene (ecoRIIR) and methyltransferase gene (ecoRIIM) in one vector and to analyze the coordinating expression of this whole R M system.Methods. Unidirectional deletion subclones were constructed with ExoIII.ecoRIIR/M genes were preliminarily located in the cloned fragment according to the enzyme activities of subclones. Exact deletion sites were determined by sequencing, and transcriptional start sites were determined by S1 mapping. Results. The DNA fragment which was cloned into pBluescript SK+contained intact ecoRIIR gene andecoRIIM gene, and two transcriptional start sites of ecoRIIR gene were determined. 132bp to 458bp from 3’end of ecoRIIR gene are indispensable to enzyme activities and deletion of 202bp from 3’end of ecoRIIM gene made enzyme lose the capability in DNA protection to resist specific cut with EcoRII endonuclease (EcoRII.R). Deletion of the coding and flanking sequences of one gene did not affect the expression of the other gene, and the recombinants only containing ecoRIIR gene appeared to be lethal to dcm+host. Conclusion. ecoRIIM gene linking closely to ecoRIIR gene is very important for the existence of the R M system in process of evolution, but the key tocontrol EcoRII R M order may not exist in transcriptional level .展开更多
The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are...The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are evaluated.Spectral analysis of the monthly AO index indicates that 23 out of the 26 CMIP5 models exhibit no statistically significant spectral peak in the historical experiment,as seen in the observations.These models are able to reproduce the AO pattern in the sea level pressure anomaly field during boreal winter,but the intensity of the AO pattern tends to be overestimated in all the models.The zonal-mean zonal wind anomalies associated with the AO is dominated by a meridional dipole in the mid-high latitudes of the Northern Hemisphere during boreal winter,which is well reproduced by only a few models.Most models show significant biases in both strength and location of the dipole compared to the observation.In considering the temporal variability as well as spatial structures in both horizontal and vertical directions,the MPI-ESM-P model reproduces an AO pattern that resembles the observation the best.展开更多
目的调查并分析晚期癌症患者年龄、性别因素对症状发生率及强度的影响。方法采用M.D安德森症状评估量表中文版(The Chinese version of the M.D Anderson Symptom Inventory,MDASI-C)对250例晚期癌症住院患者进行调查。使用Logistic回...目的调查并分析晚期癌症患者年龄、性别因素对症状发生率及强度的影响。方法采用M.D安德森症状评估量表中文版(The Chinese version of the M.D Anderson Symptom Inventory,MDASI-C)对250例晚期癌症住院患者进行调查。使用Logistic回归分析对症状进行检验以确定年龄、性别因素与症状发生率的关系,不同年龄及性别组间的症状强度比较先进行t检验再接受Bonferroni修正。结果疼痛、乏力及胃口差是最常见的症状。低龄组报告有更严重的疼痛、苦恼及悲伤感,以及更轻的健忘与更好的胃口(P<0.05);女性则有更严重的恶心症状(P=0.01)。Logistic回归分析显示低龄组发生悲伤感、苦恼、呕吐、疼痛、胃口差、恶心、睡眠不好的风险更高;男性在悲伤感、苦恼、睡眠不安以及胃口差上有更高的发生风险。结论晚期癌症患者在症状发生率及强度上存在着年龄与性别的差异,对其认识有助于理解症状的病理生理学特征及促进更加个体化的姑息治疗。展开更多
基金the National Key Technologies R & D Program of China during the 10th Five-Year Plan Period (No. 2002BA514A-12)the Education Department of Sichuan Province (No. 2006B014)the Innovative Fund for Distinguished Young Scholars of Sichuan Agricultural University, China
文摘The phyA^m gene encoding acid phytase and optimized neutral phytase phyCs gene were inserted into expression vector pPIC9K in correct orientation and transformed into Pichiapastoris in order to expand the pH profile ofphytase and decrease the cost of production. The fusion phytase phyA^m-phyCs gene was successfully overexpressed in P. pastoris as an active and extracellular phytase. The yield of total extracellular fusion phytase activity is (25.4±0.53) U/ml at the flask scale and (159.1±2.92) U/ml for high cell-density fermentation, respectively. Purified fusion phytase exhibits an optimal temperature at 55 ℃ and an optimal pH at 5.5-6.0 and its relative activity remains at a relatively high level of above 70% in the range ofpH 2.0 to 7.0. About 51% to 63% of its original activity remains after incubation at 75 ℃ to 95 ℃ for 10 min. Due to heavy glycosylation, the expressed fusion phytase shows a broad and diffuse band in SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). After deglycosylation by endoglycosidase H (EndoHf), the enzyme has an apparent molecular size of 95 kDa. The characterization of the fusion phytase was compared with those ofphyCs andphyA^m.
文摘AIM: To evaluate the influence of preoperative FOLFOX chemotherapy on CCL20/CCR6 expression in liver metastases of stage IV colorectal cancer (CRC) patients.(/7 = 53) and in patients who did not receive FOLFOX chemotherapy prior to liver surgery (n = 29). RESULTS: Of the 53 patients who received FOLFOX, time to liver surgery was n〈 1 mo in 14 patients, 〈 1 year in 22 patients and 〉 1 year in 17 patients, respectively. In addition, we investigated the proliferation rate of CRC cells in liver metastases in the different patient groups. Both CCL20 and CCR6 mRNA and protein ex- pression levels were significantly increased in patients who received preoperative FOLFOX chemotherapy ~〈 12 mo before liver surgery (P 〈 0.001) in comparison to patients who did not undergo FOLFOX treatment. Further, proliferation of CRLM cells as measured by Ki-67 was increased in patients who underwent FOLFOX treat- ment. CCL20 and CCR6 expression levels were significantly increased in CRLM patients who had undergone preoperative FOLFOX chemotherapy. CONCLUSION: This chemokine/receptor up-regulation could lead to increased proliferation/migration through an autocrine mechanism which might be used by surviving metastatic cells to escape cell death caused by FOLFOX.
基金Project supported by the National Natural Science Foundation ofChina (No. 60203030) and Advanced Research Program of France-China (Nos. PRA SI01-04 PRA SI03-02)
文摘(m, k)-firm real-time or weakly hard real-time (WHRT) guarantee is becoming attractive as it closes the gap between hard and soft (or probabilistic) real-time guarantee, and enables finer granularity of real-time QoS through adjusting m and k. For multiple streams with (m, k)-firm constraint sharing a single server, an on-line priority assignment policy based on the most recent k-length history of each stream called distance based priority (DBP) has been proposed to assign priority.In case of priority equality among these head-of-queue instances, Earliest Deadline First (EDF) is used. Under the context of WHRT schedule theory, DBP is the most popular, gets much attention and has many applications due to its straightforward priority assignment policy and easy implementation. However, DBP combined with EDF cannot always provide good performance, mainly because the initial DBP does not underline the rich information on deadline met/missed distribution,specially streams in various failure states which will travel different distances to restore success states. Considering how to effectively restore the success state of each individual stream from a failure state, an integrated DBP utilizing deadline met/missed distribution is proposed in this paper. Simulation results validated the performance improvement of this pro-posal.
文摘Objective. To clone complete EcoRII restriction endonuclease gene (ecoRIIR) and methyltransferase gene (ecoRIIM) in one vector and to analyze the coordinating expression of this whole R M system.Methods. Unidirectional deletion subclones were constructed with ExoIII.ecoRIIR/M genes were preliminarily located in the cloned fragment according to the enzyme activities of subclones. Exact deletion sites were determined by sequencing, and transcriptional start sites were determined by S1 mapping. Results. The DNA fragment which was cloned into pBluescript SK+contained intact ecoRIIR gene andecoRIIM gene, and two transcriptional start sites of ecoRIIR gene were determined. 132bp to 458bp from 3’end of ecoRIIR gene are indispensable to enzyme activities and deletion of 202bp from 3’end of ecoRIIM gene made enzyme lose the capability in DNA protection to resist specific cut with EcoRII endonuclease (EcoRII.R). Deletion of the coding and flanking sequences of one gene did not affect the expression of the other gene, and the recombinants only containing ecoRIIR gene appeared to be lethal to dcm+host. Conclusion. ecoRIIM gene linking closely to ecoRIIR gene is very important for the existence of the R M system in process of evolution, but the key tocontrol EcoRII R M order may not exist in transcriptional level .
基金supported by the National Basic Research Program of China(No.2010CB950501&2010CB950404)the National Natural Science Foundation of China(No.41205058)the China Postdoctoral Sci-ence Foundation(No.2012M510634)
文摘The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are evaluated.Spectral analysis of the monthly AO index indicates that 23 out of the 26 CMIP5 models exhibit no statistically significant spectral peak in the historical experiment,as seen in the observations.These models are able to reproduce the AO pattern in the sea level pressure anomaly field during boreal winter,but the intensity of the AO pattern tends to be overestimated in all the models.The zonal-mean zonal wind anomalies associated with the AO is dominated by a meridional dipole in the mid-high latitudes of the Northern Hemisphere during boreal winter,which is well reproduced by only a few models.Most models show significant biases in both strength and location of the dipole compared to the observation.In considering the temporal variability as well as spatial structures in both horizontal and vertical directions,the MPI-ESM-P model reproduces an AO pattern that resembles the observation the best.
文摘目的调查并分析晚期癌症患者年龄、性别因素对症状发生率及强度的影响。方法采用M.D安德森症状评估量表中文版(The Chinese version of the M.D Anderson Symptom Inventory,MDASI-C)对250例晚期癌症住院患者进行调查。使用Logistic回归分析对症状进行检验以确定年龄、性别因素与症状发生率的关系,不同年龄及性别组间的症状强度比较先进行t检验再接受Bonferroni修正。结果疼痛、乏力及胃口差是最常见的症状。低龄组报告有更严重的疼痛、苦恼及悲伤感,以及更轻的健忘与更好的胃口(P<0.05);女性则有更严重的恶心症状(P=0.01)。Logistic回归分析显示低龄组发生悲伤感、苦恼、呕吐、疼痛、胃口差、恶心、睡眠不好的风险更高;男性在悲伤感、苦恼、睡眠不安以及胃口差上有更高的发生风险。结论晚期癌症患者在症状发生率及强度上存在着年龄与性别的差异,对其认识有助于理解症状的病理生理学特征及促进更加个体化的姑息治疗。