Aim To optimize purification conditions of recombinant hirudin 3 in thefermentation broth and characterize the product. Methods Reambinant hirudin 3 was isolated andpurified from the fermentation broth by three column...Aim To optimize purification conditions of recombinant hirudin 3 in thefermentation broth and characterize the product. Methods Reambinant hirudin 3 was isolated andpurified from the fermentation broth by three column chromatography steps with macroporous resin,DEAE cellulose DES2 and preparative RP-HPLC, respectively, and the optimal conditions were obtained.Purity of the product was determined by SDS-PAGE and analytical RP-HPLC. The molecular weight wasdetermined by mass spec-trometry. The structure of the product was analyzed by peptide map.ResultsThe product with purity of 95.4786% was obtained after three purification steps in the optimumconditions with a total yield of 39%. The molecular weight of the product was 6 913.32 ± 6.55 Da,coincident to the theoretical molecular weight of r-hirudin 3. The structure of the product wascoincident to r-hirudin 3 either. Conclusion The optimized purification steps can be successfullyemployed for purification of r-hirudin 3 from E. coli using batch-type approaches. The productobtained with high purity was confirmed to be r-hirudin 3.展开更多
Objective: To inhibit specifically survivin expression and block its function in leukemia cells, an antisense RNA expression plasmid for survivin was constructed and transfected into a leukemia cell line.Methods: A cD...Objective: To inhibit specifically survivin expression and block its function in leukemia cells, an antisense RNA expression plasmid for survivin was constructed and transfected into a leukemia cell line.Methods: A cDNA fragment of survivin obtained by RT-PCR was inserted into a plasmid vector named pcDNA3 in the reverse direction. Antisense RNA of survivin was confirmed by restriction enzyme digestion and DNA sequencing. The recombinant plasmid was transfected into the cell line HL-60 by electroporation. The effect of survivin antisense RNA on survivin mRNA expression in transfected cells was examined by RT-PCR.Results: The correct construction of the recombinant plasmid has been shown by restriction enzyme digestion and DNA sequencing. As compared to controls, the level of survivin mRNA expression in transfected cells decreased significantly.Conclusion: An antisense RNA vector for survivin has been successfully constructed and may be useful as a specific inhibitor in leukemia cells. Thus, antisense therapy on the basis of survivin can be further explored in leukemia. Key words leukemia - survivin - antisense RNA This project was supported by a grant from National Key Basis Research Program of China (No. CB 513109) and the National Natural Sciences Foundation of China (No. 39970693).展开更多
[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Met...[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast.展开更多
Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with e...Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with elemental analysis, one- and two-dimension spectra NMR (DEPT, 1H-1Hcosy, HMQC, HMBC) and compared with those of mifepristone.Results The main by-product was 11,17-di-addition product of Grignard reagent of N, N-dimethylamino phenyl bromide.Conclusion This is the first complete assignment of 1H NMR and 13C NMR of compound (3).展开更多
The rare ginsenoside Compound K （C-K） is attracting more attention because of its good physiological activity and urgent need. There are many pathways to obtain ginsenoside C-K, including chemical and biological met...The rare ginsenoside Compound K （C-K） is attracting more attention because of its good physiological activity and urgent need. There are many pathways to obtain ginsenoside C-K, including chemical and biological methods. Among these, the conversion of PPD-type ginsenosides by enzymatic hydrolysis is a trend due to its high efficiency and mild conditions. For effectively extracting from the other panaxadiol saponins, the conversion process for ginsenoside C-K was investigated using snailases in this study. The univariate experimental design and response surface methodology were used to determine the optimal hydrolysis conditions for the conversion of ginsenoside Rbl into ginsenoside C-K by snailases. The optimum conditions were as follows： pH 5,12, temperature 51 ℃, ratio of snailase/substrate 0.21, and reaction time 48 h. On the basis of these parameters, the addition of 1.0 mmol· L- 1 ferric ion was found to significantly improve the enzymolysis ofsnailases for the first time. With the above conditions, the maximum conversion rate reached 89.7%, suggesting that the process can obviously increase the yield of ginsenoside C-K. The bioassay tests indicated that the ginsenoside C-K showed anti-tumor activity in a series of tumor cell lines. Based on these results, we can conclude that the process of rare ginsenoside C- K production by enzymolysis with snailase is feasible, efficient, and suitable for the industrial production and application.展开更多
Batch processes are important in chemical industry,in which operators usually play a major role and hazards may arise by their inadvertent acts.In this paper,based on hazard and operability study and concept of qualit...Batch processes are important in chemical industry,in which operators usually play a major role and hazards may arise by their inadvertent acts.In this paper,based on hazard and operability study and concept of qualitative simulation,an automatic method for adverse consequence identification for potential maloperation is proposed.The qualitative model for production process is expressed by a novel directed graph.Possible operation deviations from normal operating procedure are identified systematically by using a group of guidewords.The proposed algorithm is used for qualitative simulation of batch processes to identify the effects of maloperations.The method is illustrated with a simple batch process and a batch reaction process.The results show that batch processes can be simulated qualitatively and hazards can be identified for operating procedures including maloperations.After analysis for possible plant maloperations,some measures can be taken to avoid maloperations or reduce losses resulted from maloperations.展开更多
AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout microarray.METHODS:Differential methylation profile was compared between normal bile duct epitheli...AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout microarray.METHODS:Differential methylation profile was compared between normal bile duct epithelial cell lines and CCA cell lines by methyl-DNA immunoprecipitation (MeDIP)microarray.Bisulfite-polymerase chain reaction (BSP)was performed to identify the methylated allels of target genes.Expression of target genes was investigated before and after the treatment with DNA demethylating agent.Expression of candidate genes was also evaluated by immunofluorescence in 30 specimens of CCA tissues and 9 normal bile duct tissues.RESULTS:Methylation profile of CCA was identified with MeDIP microarray in the respects of different gene functions and signaling pathways.Interestingly,97 genes with hypermethylated CpG islands in the promoter region were homeobox genes.The top 5 hypermethylated homeobox genes validated by BSP were HOXA2(94.29%),HOXA5(95.38%),HOXA11 (91.67%),HOXB4(90.56%)and HOXD13(94.38%).Expression of these genes was reactivated with 5’-aza2’-deoxycytidine.Significant expression differences were found between normal bile duct and extrahepatic CCA tissues(66.67%-100%vs 3.33%-10%).CONCLUSION:HOXA2,HOXA5,HOXA11,HOXB4 and HOXD13 may work as differential epigenetic biomarkers between malignant and benign biliary tissues.展开更多
In this paper, Neural Networks （NNs） are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverabil...In this paper, Neural Networks （NNs） are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverability indices and linear non-dimensional hydrodynamic derivatives in the models are identified by using two-layer feed forward NNs. The stability of parametric estimation is confirmed. Then, the ship maneuvering motion is predicted based on the obtained models. A comparison between the predicted results and the model test results demonstrates the validity of the proposed modeling method.展开更多
[Objective] This study aimed to establish an identification system for drought-resistance in wheat by using near-infrared diffuse reflectance spectroscopy. [Method] In 2006-2007, 36 wheat varieties with different drou...[Objective] This study aimed to establish an identification system for drought-resistance in wheat by using near-infrared diffuse reflectance spectroscopy. [Method] In 2006-2007, 36 wheat varieties with different drought resistance were selected and were classified according to their drought resistance grades determined by the Technical Specification of Identification and Evaluation for Drought Resistance in Wheat （GB/T 21127-2007）. In addition, the harvested wheat seed samples were spectrally analyzed with FOSS NIRSystems5000 near-infrared spectrum analyzer for grain quality （full spectrum analyzer） and then the forecasted regression equations were established. [Result] After the establishment of a database and validation, dis- criminated functions were obtained. The determination coefficient （RSQ） and coeffi- cients of determination for cross validation （1-VR） in the discriminant function built with seed samples from water stress area were 0.846 0 and 0.781 8, respectively, which indicated that the consistency between drought resistance and spectral charac- teristics in wheat varieties was good, and there was high correlation between the near-infrared diffuse reflectance spectra of seeds and the drought resistance in wheat. [Conclusiou] Under water stress condition, it is feasible to establish a conve- nient, rapid and no-damage identification system for the drought resistance in wheat by using the near-infrared diffuse reflectance spectrum technique to scan wheat seeds.展开更多
Thioredoxin （Trx） proteins are involved in many biological processes especially the regulation of cellular redox homeostasis. In this study, two Trx cDNAs were cloned from the mussel Mytilus galloprovincialis using ...Thioredoxin （Trx） proteins are involved in many biological processes especially the regulation of cellular redox homeostasis. In this study, two Trx cDNAs were cloned from the mussel Mytilus galloprovincialis using rapid amplification of cDNA ends-polymerase chain reaction （RACE-PCR）. The two cDNAs were named MgTrxl and MgTrx2, respectively. The open reading frames of MgTrxl and MgTrx2 were 318 and 507 base pairs （bp） and they encoded proteins of 105 and 168 amino acids with estimated molecular masses of 11.45 and 18.93 kDa, respectively. Sequence analysis revealed that both proteins possessed the conserved active site dithiol motif Cys-Gly-Pro-Cys. In addition, MgTrx2 also possessed a putative mitochondrial targeting signal suggesting that it is located in the mitochondria. Quantitative real-time polymerase chain reaction （qPCR） revealed that both MgTrxl and MgTrx2 were constitutively expressed in all tissues examined. The MgTrxl transcript was most abundant in hemocytes and gills, whereas the MgTrx2 transcript was most abundant in gonad, hepatopancreas, gill and hemocytes. Following Vibrio anguillarum challenge, the expression of MgTrxl was up-regulated and reached its peak, at a value 10-fold the initial value, at 24 h. Subsequently, expression returned back to the original level. In contrast, the expression level of MgTrx2 was down-regulated following bacterial stimulation, with one fifth of the control level evident at 12 h post challenge. These results suggest that MgTrxl and MgTrx2 may play important roles in the response ofM. galloprovincialis to bacterial challenge.展开更多
AIM:To analyse the possible association of various Helicobacter species and certain common gut bacteria in patients with Meckel's diverticulum and appendicitis.METHODS:A nested-polymerase chain reaction (PCR),spec...AIM:To analyse the possible association of various Helicobacter species and certain common gut bacteria in patients with Meckel's diverticulum and appendicitis.METHODS:A nested-polymerase chain reaction (PCR),specific to 16S rRNA of the Helicobacter genus,was performed on paraffin embedded samples,50 with acute appendicitis,50 normal appendixes,and 33 Meckel's diverticulum with gastric heterotopia and/or ulcer.Helicobacter genus positive samples were sequenced for species identification.All samples were also analysed for certain gut bacteria by PCR.RESULTS:Helicobacter pullorum DNA was found in one out of 33 cases and Enterobacteria in two cases of Meckel's diverticulum.Helicobacter pylori (H.pylori) was found in three,Enterobacter in 18,and Bacteroides in 19 out of 100 appendix samples by PCR.Enterococcus was not found in any MD or appendix samples.All H.pylori positive cases were from normal appendixes.CONCLUSION:Helicobacter is not an etiological agent in the pathogenesis of symptomatic Meckel's diverticulum or in acute appendicitis.展开更多
To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria （SDPB） that are capable of enhanced biological phosphorus removal （EBPR） using nitrite as an elec...To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria （SDPB） that are capable of enhanced biological phosphorus removal （EBPR） using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand （COD）, phosphate, nitrite, poly-fl-hydroxybutyrate （PHB）, and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release （96.2%） under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation （91.3%） and a little for glycogen synthesis （8.7%）. This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms （PAOs）. It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring AP/APHB and ANO2 -N/APHB is more necessary than monitoring AP/ACOD, ANO2 -N/ACOD, or AP / ANO2 -N.展开更多
The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop ...The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop （Chlamysfarreri）, and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 （CflSoxB2） were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group （HMG） box. The full-length cDNA sequence of CJSoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of CJSoxB2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of CfS;oxB2 were similar. Considering the specific expression and roles of SoxB2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for SoxB2 in C.farreri.展开更多
The detection and identification of gross errors, especially measurement bias, plays a vital role in data reconciliation for nonlinear dynamic systems. Although parameter estimation method has been proved to be a pow-...The detection and identification of gross errors, especially measurement bias, plays a vital role in data reconciliation for nonlinear dynamic systems. Although parameter estimation method has been proved to be a pow-erful tool for bias identification, without a reliable and efficient bias detection strategy, the method is limited in ef-ficiency and cannot be applied widely. In this paper, a new bias detection strategy is constructed to detect the pres-ence of measurement bias and its occurrence time. With the help of this strategy, the number of parameters to be es-timated is greatly reduced, and sequential detections and iterations are also avoided. In addition, the number of de-cision variables of the optimization model is reduced, through which the influence of the parameters estimated is reduced. By incorporating the strategy into the parameter estimation model, a new methodology named IPEBD (Improved Parameter Estimation method with Bias Detection strategy) is constructed. Simulation studies on a con-tinuous stirred tank reactor (CSTR) and the Tennessee Eastman (TE) problem show that IPEBD is efficient for eliminating random errors, measurement biases and outliers contained in dynamic process data.展开更多
文摘Aim To optimize purification conditions of recombinant hirudin 3 in thefermentation broth and characterize the product. Methods Reambinant hirudin 3 was isolated andpurified from the fermentation broth by three column chromatography steps with macroporous resin,DEAE cellulose DES2 and preparative RP-HPLC, respectively, and the optimal conditions were obtained.Purity of the product was determined by SDS-PAGE and analytical RP-HPLC. The molecular weight wasdetermined by mass spec-trometry. The structure of the product was analyzed by peptide map.ResultsThe product with purity of 95.4786% was obtained after three purification steps in the optimumconditions with a total yield of 39%. The molecular weight of the product was 6 913.32 ± 6.55 Da,coincident to the theoretical molecular weight of r-hirudin 3. The structure of the product wascoincident to r-hirudin 3 either. Conclusion The optimized purification steps can be successfullyemployed for purification of r-hirudin 3 from E. coli using batch-type approaches. The productobtained with high purity was confirmed to be r-hirudin 3.
基金This project was supported by a grant from National Key Basis Research Program of China(No.CB 513109)and the NationalNatural Sciences Foundation of China(No.39970693).
文摘Objective: To inhibit specifically survivin expression and block its function in leukemia cells, an antisense RNA expression plasmid for survivin was constructed and transfected into a leukemia cell line.Methods: A cDNA fragment of survivin obtained by RT-PCR was inserted into a plasmid vector named pcDNA3 in the reverse direction. Antisense RNA of survivin was confirmed by restriction enzyme digestion and DNA sequencing. The recombinant plasmid was transfected into the cell line HL-60 by electroporation. The effect of survivin antisense RNA on survivin mRNA expression in transfected cells was examined by RT-PCR.Results: The correct construction of the recombinant plasmid has been shown by restriction enzyme digestion and DNA sequencing. As compared to controls, the level of survivin mRNA expression in transfected cells decreased significantly.Conclusion: An antisense RNA vector for survivin has been successfully constructed and may be useful as a specific inhibitor in leukemia cells. Thus, antisense therapy on the basis of survivin can be further explored in leukemia. Key words leukemia - survivin - antisense RNA This project was supported by a grant from National Key Basis Research Program of China (No. CB 513109) and the National Natural Sciences Foundation of China (No. 39970693).
基金Supported by National 863 Project of China (2002AA227011)Natural Science Foundation of Hubei Province (2003ABAI18)Natural Science Foundation of Shandong Province (ZR2010HQ054)~~
文摘[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast.
文摘Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with elemental analysis, one- and two-dimension spectra NMR (DEPT, 1H-1Hcosy, HMQC, HMBC) and compared with those of mifepristone.Results The main by-product was 11,17-di-addition product of Grignard reagent of N, N-dimethylamino phenyl bromide.Conclusion This is the first complete assignment of 1H NMR and 13C NMR of compound (3).
基金Supported by the National Natural Science Foundation of China(21476182,21776227,21776228)Shaanxi Key Laboratory of Degradable Biomedical Materials Program(2014SZS07-K04,2014SZS07-P05,15JS106,2014SZS07-Z01,2014SZS07-Z02,2016SZSj-35,2014SZS07-K03)Shaanxi R&D Center of Biomaterials and Fermentation Engineering Program(2015HBGC-04)
文摘The rare ginsenoside Compound K （C-K） is attracting more attention because of its good physiological activity and urgent need. There are many pathways to obtain ginsenoside C-K, including chemical and biological methods. Among these, the conversion of PPD-type ginsenosides by enzymatic hydrolysis is a trend due to its high efficiency and mild conditions. For effectively extracting from the other panaxadiol saponins, the conversion process for ginsenoside C-K was investigated using snailases in this study. The univariate experimental design and response surface methodology were used to determine the optimal hydrolysis conditions for the conversion of ginsenoside Rbl into ginsenoside C-K by snailases. The optimum conditions were as follows： pH 5,12, temperature 51 ℃, ratio of snailase/substrate 0.21, and reaction time 48 h. On the basis of these parameters, the addition of 1.0 mmol· L- 1 ferric ion was found to significantly improve the enzymolysis ofsnailases for the first time. With the above conditions, the maximum conversion rate reached 89.7%, suggesting that the process can obviously increase the yield of ginsenoside C-K. The bioassay tests indicated that the ginsenoside C-K showed anti-tumor activity in a series of tumor cell lines. Based on these results, we can conclude that the process of rare ginsenoside C- K production by enzymolysis with snailase is feasible, efficient, and suitable for the industrial production and application.
文摘Batch processes are important in chemical industry,in which operators usually play a major role and hazards may arise by their inadvertent acts.In this paper,based on hazard and operability study and concept of qualitative simulation,an automatic method for adverse consequence identification for potential maloperation is proposed.The qualitative model for production process is expressed by a novel directed graph.Possible operation deviations from normal operating procedure are identified systematically by using a group of guidewords.The proposed algorithm is used for qualitative simulation of batch processes to identify the effects of maloperations.The method is illustrated with a simple batch process and a batch reaction process.The results show that batch processes can be simulated qualitatively and hazards can be identified for operating procedures including maloperations.After analysis for possible plant maloperations,some measures can be taken to avoid maloperations or reduce losses resulted from maloperations.
基金Supported by The grant for"Development of Novel Nano-Drug Delivery System Loaded with Traditional Chinese Anticancer Medicine for the Targeted Therapy of Malignant Tumors"issued by the Chinese Ministry of Science and Technology,Grant No. 2010DFA31870
文摘AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout microarray.METHODS:Differential methylation profile was compared between normal bile duct epithelial cell lines and CCA cell lines by methyl-DNA immunoprecipitation (MeDIP)microarray.Bisulfite-polymerase chain reaction (BSP)was performed to identify the methylated allels of target genes.Expression of target genes was investigated before and after the treatment with DNA demethylating agent.Expression of candidate genes was also evaluated by immunofluorescence in 30 specimens of CCA tissues and 9 normal bile duct tissues.RESULTS:Methylation profile of CCA was identified with MeDIP microarray in the respects of different gene functions and signaling pathways.Interestingly,97 genes with hypermethylated CpG islands in the promoter region were homeobox genes.The top 5 hypermethylated homeobox genes validated by BSP were HOXA2(94.29%),HOXA5(95.38%),HOXA11 (91.67%),HOXB4(90.56%)and HOXD13(94.38%).Expression of these genes was reactivated with 5’-aza2’-deoxycytidine.Significant expression differences were found between normal bile duct and extrahepatic CCA tissues(66.67%-100%vs 3.33%-10%).CONCLUSION:HOXA2,HOXA5,HOXA11,HOXB4 and HOXD13 may work as differential epigenetic biomarkers between malignant and benign biliary tissues.
基金Partially Supported by the Special Item for the Fujian Provincial Department of Ocean and Fisheries(No.MHGX-16)the Special Item for Universities in Fujian Province by the Education Department(No.JK15003)
文摘In this paper, Neural Networks （NNs） are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverability indices and linear non-dimensional hydrodynamic derivatives in the models are identified by using two-layer feed forward NNs. The stability of parametric estimation is confirmed. Then, the ship maneuvering motion is predicted based on the obtained models. A comparison between the predicted results and the model test results demonstrates the validity of the proposed modeling method.
基金Supported by the Special Fund for the Industrial Technology System Construction of Modern Agriculture in Wheat(CARS-E-2-36)the Special Fund for Henan Industrial Technology System Construction of Modern Agriculture in Wheat(S2010-10-02)National Support Program for Science and Technology(2011BAD35B03)~~
文摘[Objective] This study aimed to establish an identification system for drought-resistance in wheat by using near-infrared diffuse reflectance spectroscopy. [Method] In 2006-2007, 36 wheat varieties with different drought resistance were selected and were classified according to their drought resistance grades determined by the Technical Specification of Identification and Evaluation for Drought Resistance in Wheat （GB/T 21127-2007）. In addition, the harvested wheat seed samples were spectrally analyzed with FOSS NIRSystems5000 near-infrared spectrum analyzer for grain quality （full spectrum analyzer） and then the forecasted regression equations were established. [Result] After the establishment of a database and validation, dis- criminated functions were obtained. The determination coefficient （RSQ） and coeffi- cients of determination for cross validation （1-VR） in the discriminant function built with seed samples from water stress area were 0.846 0 and 0.781 8, respectively, which indicated that the consistency between drought resistance and spectral charac- teristics in wheat varieties was good, and there was high correlation between the near-infrared diffuse reflectance spectra of seeds and the drought resistance in wheat. [Conclusiou] Under water stress condition, it is feasible to establish a conve- nient, rapid and no-damage identification system for the drought resistance in wheat by using the near-infrared diffuse reflectance spectrum technique to scan wheat seeds.
基金Supported by the National Natural Science Foundation of China(No.31172388)the 100 Talents Program of the Chinese Academy of Sciencesthe Key Laboratory for Ecological Environment in Coastal Areas(201011),State Oceanic Administration
文摘Thioredoxin （Trx） proteins are involved in many biological processes especially the regulation of cellular redox homeostasis. In this study, two Trx cDNAs were cloned from the mussel Mytilus galloprovincialis using rapid amplification of cDNA ends-polymerase chain reaction （RACE-PCR）. The two cDNAs were named MgTrxl and MgTrx2, respectively. The open reading frames of MgTrxl and MgTrx2 were 318 and 507 base pairs （bp） and they encoded proteins of 105 and 168 amino acids with estimated molecular masses of 11.45 and 18.93 kDa, respectively. Sequence analysis revealed that both proteins possessed the conserved active site dithiol motif Cys-Gly-Pro-Cys. In addition, MgTrx2 also possessed a putative mitochondrial targeting signal suggesting that it is located in the mitochondria. Quantitative real-time polymerase chain reaction （qPCR） revealed that both MgTrxl and MgTrx2 were constitutively expressed in all tissues examined. The MgTrxl transcript was most abundant in hemocytes and gills, whereas the MgTrx2 transcript was most abundant in gonad, hepatopancreas, gill and hemocytes. Following Vibrio anguillarum challenge, the expression of MgTrxl was up-regulated and reached its peak, at a value 10-fold the initial value, at 24 h. Subsequently, expression returned back to the original level. In contrast, the expression level of MgTrx2 was down-regulated following bacterial stimulation, with one fifth of the control level evident at 12 h post challenge. These results suggest that MgTrxl and MgTrx2 may play important roles in the response ofM. galloprovincialis to bacterial challenge.
基金Supported by A grant from the University Hospital of Lund(ALF) to Torkel Wadstrm and a grant from the JohnForssman's foundation,the Royal Physiographic Society in Lund to Peren Karagin
文摘AIM:To analyse the possible association of various Helicobacter species and certain common gut bacteria in patients with Meckel's diverticulum and appendicitis.METHODS:A nested-polymerase chain reaction (PCR),specific to 16S rRNA of the Helicobacter genus,was performed on paraffin embedded samples,50 with acute appendicitis,50 normal appendixes,and 33 Meckel's diverticulum with gastric heterotopia and/or ulcer.Helicobacter genus positive samples were sequenced for species identification.All samples were also analysed for certain gut bacteria by PCR.RESULTS:Helicobacter pullorum DNA was found in one out of 33 cases and Enterobacteria in two cases of Meckel's diverticulum.Helicobacter pylori (H.pylori) was found in three,Enterobacter in 18,and Bacteroides in 19 out of 100 appendix samples by PCR.Enterococcus was not found in any MD or appendix samples.All H.pylori positive cases were from normal appendixes.CONCLUSION:Helicobacter is not an etiological agent in the pathogenesis of symptomatic Meckel's diverticulum or in acute appendicitis.
基金Supported by the Nafional Natural Science Foundation of China （51078008）, the Natural Science Foundation of Guangdong Province （06022869, 07003251）, and the National Key Scientific and Technological Project Water Pollution Control and Treatment （2008ZX07211-003, 2009ZX07314-009-003）.
文摘To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria （SDPB） that are capable of enhanced biological phosphorus removal （EBPR） using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand （COD）, phosphate, nitrite, poly-fl-hydroxybutyrate （PHB）, and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release （96.2%） under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation （91.3%） and a little for glycogen synthesis （8.7%）. This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms （PAOs）. It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring AP/APHB and ANO2 -N/APHB is more necessary than monitoring AP/ACOD, ANO2 -N/ACOD, or AP / ANO2 -N.
基金Supported by the National Natural Science Foundation of China(Nos.31072190,30972239)the National Basic Research Program of China(973 Program)(No.2010CB126406)+2 种基金the Taishan Scholar Program of Shandong Provincethe Doctoral Fund of Ministry of Education of China(No.20100132110014)the Natural Science Foundation of Shandong Province(No.ZR2009DM019)
文摘The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop （Chlamysfarreri）, and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 （CflSoxB2） were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group （HMG） box. The full-length cDNA sequence of CJSoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of CJSoxB2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of CfS;oxB2 were similar. Considering the specific expression and roles of SoxB2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for SoxB2 in C.farreri.
基金Supported by the National High Technology Research and Development Program of China (2006AA04Z176)
文摘The detection and identification of gross errors, especially measurement bias, plays a vital role in data reconciliation for nonlinear dynamic systems. Although parameter estimation method has been proved to be a pow-erful tool for bias identification, without a reliable and efficient bias detection strategy, the method is limited in ef-ficiency and cannot be applied widely. In this paper, a new bias detection strategy is constructed to detect the pres-ence of measurement bias and its occurrence time. With the help of this strategy, the number of parameters to be es-timated is greatly reduced, and sequential detections and iterations are also avoided. In addition, the number of de-cision variables of the optimization model is reduced, through which the influence of the parameters estimated is reduced. By incorporating the strategy into the parameter estimation model, a new methodology named IPEBD (Improved Parameter Estimation method with Bias Detection strategy) is constructed. Simulation studies on a con-tinuous stirred tank reactor (CSTR) and the Tennessee Eastman (TE) problem show that IPEBD is efficient for eliminating random errors, measurement biases and outliers contained in dynamic process data.
