[ Objective] In order to study the relation between the HSPTO gene and male sterility of plant further. [ Methods ] Anther specific expression promoter Osg6B of rice was coloned by PCR then connected with HSP70 antise...[ Objective] In order to study the relation between the HSPTO gene and male sterility of plant further. [ Methods ] Anther specific expression promoter Osg6B of rice was coloned by PCR then connected with HSP70 antisense fragment to construct HSPTO antisense expression vector. The expression vector was identified by PCR experiment and enzyme digestion. [ Result] The sequence of coloned Osg6B promoter had 97% homology to the published sequence, and the cis-regulatory element in promoter area was integrated. HSP70 antisense expression vector driven by the promoter Osg6B was confired by colony PCR and enzyme digestion. [ Conclusion] The construction of expression vector would lay solid foundation for utilization of genetic engineering male sterility of plant.展开更多
Objective: To explore and investigate the selection of effective antisense oligodeoxynuleotides with the help of computer and RNAstructure folding software. Methods: Bcl-2 gene was used as the target gene and five a...Objective: To explore and investigate the selection of effective antisense oligodeoxynuleotides with the help of computer and RNAstructure folding software. Methods: Bcl-2 gene was used as the target gene and five antisense oligodeoxynuleotides were designed to be bound to Bcl-2 mRNA optimal secondary structure regions that were predicted free from intramolecular fold or instability of free energy. The five antisense oligodeoxynucleotides were studied with experimental assay of leukemia cells, including cell grow assay with tropan blue exclusion, expression of Bcl-2 protein detected with immunochemistry and flowcytometry, Bcl-2 mRNA content detected with RT-PCR technique, as well as apoptosis observed and determined with morphonological method, electrophoresis and flowcytometry. Results: The results showed that two of the five antisense oligodeoxynucleotides were effective antisense oligodeoxynucleotides, which were able to inhibit cell growth in leukemia, to decrease the level of Bcl-2 mRNA and protein, to induce apoptosis of leukemia cells significantly. Conclusion: The computational prediction of antisense efficacy is faster than other methods and more efficient, which can potentially speed the development of sequences for both research and clinical applications.展开更多
Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeox...Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and puri?ed. Telomerase activity was detected by Telomerase PCR ELASA kit and cell apoptosis was observed by morphological method and determined by ?owcytometry. Results: AS PS-ODN could signi?cantly inhibit telomerase activity by down regulat- ing the hTERT expression, and increase the susceptibility of leukemic cells to CDDP-induced apoptosis. Conclusion: Inhibition of telomerase with hTERT antisense can increases the susceptibility of leukemic cells to CDDP-induced apoptosis.展开更多
cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically...cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically in the developing secondary xylem and its expression was coincident with lignification. The antisense CCoAOMT cDNA was transformed into P. tremula x P. alba mediated by Agrobacterium tumefaciens ( Smith et Townsend) Conn. Transgenic plants were identified with PCR, PCR-Southern and Southern analysis. Lignin content in 5- to 6-month-old transgenic plants was measured. One of the transgenic lines had significant reduction of 17.9% in Klason lignin content as compared with that of untransformed poplar. The results demonstrate that antisense repression of CCoAOMT is an efficient way to reduce lignin content for improving pulping property in engineered trees.展开更多
In order to create the Male Sterile Line in tobacco, the anti-sense fragment of HSP70 gene was linked to anther specific expression promoter TA29 and the reconstructed vector was transformed into tobacco by Agrobacter...In order to create the Male Sterile Line in tobacco, the anti-sense fragment of HSP70 gene was linked to anther specific expression promoter TA29 and the reconstructed vector was transformed into tobacco by Agrobacterium mediated transformation, and the transformants were then screened. Gus and spot blotting hybridization analysis of the transformants indicated that anti-sense fragment of HSF70 gene had been integrated into tobacco genome and expressed, thus the male sterile tobacco line was obtained. Microscope observation of anther and pollen showed that pistils of transgenic tobacco were normal, whereas anthers and pollens were fairly abortive in the same transgenic tobacco flower, comparing with pistils and stamens in control plants. The ratio of HSI:'70 protein before and after heat shock in mitochondrial was found to be 1.39 in control tobacco plants and 1.01 in transgenic tobacco sterile lines. This is suggested that the anti-sense gene fragment of HSP70 can effectively inhibit the expression of HSP70 protein and lead to transgenic male sterility in tobacco flowers. The assay provided a new genetic engineering method for male sterility creation in plants.展开更多
Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention t...Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention therapy. Methods: Eighteen patients with central lungcancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchialartery reconstruction was done at the console work-station. The space anatomical characters ofbronchial artery were observed through different rotations. Results: For 6 cases, thethree-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes(lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate ofbronchial arteries was the highest in pulmonary artery stricture and truncation groups, and thevessels' diameter became larger apparently. These characters demonstrated blood supply of this kindof central lung cancer come from bronchial artery. Volume rendering images were the best ones amongthree-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery canreveal the anatomical characters of bronchial artery and provide theoretical evidence on bloodsupply and intervention therapy of central lung cancer.展开更多
Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense ge...Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense genes. Previ- ous studies have focused on the non-coding antisense genes, but the possible regulatory role of the antisense protein is poorly understood. In this study, we found that a protein encoded by the antisense gene ADF1 acts as a transcription suppressor, regulating the expression of sense gene MDF1 in Saccharomyces cerevisiae. Based on the evolutionary, ge- netic, cytological and biochemical evidence, we show that the protein-coding sense gene MDF1 most likely originated de novo from a previously non-coding sequence and can significantly suppress the mating efficiency of baker's yeast in rich medium by binding MATa2 and thus promote vegetative growth. These results shed new light on several im- portant issues, including a new sense-antisense interaction mechanism, the de novo origination of a functional gene, and the regulation of yeast mating pathway.展开更多
Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard t...Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhH/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC- associated HBV mutants may not transmit via motherto-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic suscep-tibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active antiviral treatments.展开更多
AIM:To identify and assess mutations in the K-ras and BRAF genes in a cohort of Chinese patients with colorectal cancer (CRC) for their association with various clinicopathological parameters and prognosis.METHODS:Gen...AIM:To identify and assess mutations in the K-ras and BRAF genes in a cohort of Chinese patients with colorectal cancer (CRC) for their association with various clinicopathological parameters and prognosis.METHODS:Genomic DNA was isolated from frozen tissues.Pyrosequencing analysis was conducted to detect mutations in the K-ras (codons 12,13,and 61) and BRAF genes (codon 600).Statistical analysis was carried out using SPSS-15.0 software.RESULTS:Among the 118 colorectal cancer patients,we detected 41 (34.7%) mutations in the K-ras gene.Mutation frequencies at codon 12 and codon 13 were 23.7% (28/118) and 10.2% (12/118),respectively.Only one patient harbored a point mutation at codon 61 (0.8%,1/118).Gender was the only factor that showed an obvious relationship with K-ras gene mutation (female 44.7% vs male 28.2%,P=0.037).Other clinicopathological features,such as age,location of the tumor,tumor differentiation,Tumor,Node and Metastases classification,and the Union for International Cancer Control staging,showed no positive relationship with K-ras gene mutations.No significant correlation was observed between the presence of K-ras mutations (codons 12,13,and 61) and the survival of the patients.BRAF mutations were rare,and only two patients (1.7%) harbored a detectable mutation at codon 600.CONCLUSION:K-ras gene mutation is a common event in our 118 Chinese CRC patients,with an obvious relationship with gender.However,it seems not to be an independent prognostic factor in CRC patients.The BRAF gene is rarely mutated in Chinese CRC patients.展开更多
Objective To investigate the expression of the preferentially expressed antigen of melanoma (PRAME) gene in acute leukemia and its clinical significance. Methods The level of expressed PRAME mRNA in bone marrow mono...Objective To investigate the expression of the preferentially expressed antigen of melanoma (PRAME) gene in acute leukemia and its clinical significance. Methods The level of expressed PRAME mRNA in bone marrow mononuclear cells from 34 patients with acute leukemia (AL) and in 12 bone marrow samples from healthy volunteers was measured via RT-PCR. Correlation analyses between PRAME gene expression and the clinical characteristics (gender, age, white blood count, immunophenotype of leukemia, percentage of blast cells, and karyotype) of the patients were performed. Results The PRAME gene was expressed in 38.2% of all 34 patients, in 40.7% of the patients with acute myelogenous leukemia (AML, n=27), and in 28.6% of the patients with acute lymphoblastic leukemia (ALL, n=7), but was not expressed in the healthy volunteers. The difference in the expression levels between AML and ALL patients was statistically significant. The rate of gene expression was 80% in M~, 33.3% in M2, and 28.6% in M~. Gene expression was also found to be correlated with CDl5 and CD33 expression and abnormal karyotype, but not with age, gender; white blood count or percentage of blast cells. Conclusions The PRAME gene is highly expressed in acute leukemia and could be a useful marker to monitor minimal residual disease. This gene is also a candidate target for the immunotherapy of acute leukemia.展开更多
Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymera...Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA) in K562 cellstreated with ASODN and hTERT mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results The hTERT mRNA level was decreased, and teloraerase activity was significantly inhibited when the K562 cells were treated withASODN for 48 h.Conclusion It is suggested that hTERT ASODN might specifically inhibit telomerase activity of K562 cells at translation level, and it isfurther proved that hTERT gene has significant correlation with telomerase activity.展开更多
This paper is devoted to investigating exact solutions of a generalized fractional nonlinear anomalousdiffusion equation in radical symmetry.The presence of external force and absorption is also considered.We firstinv...This paper is devoted to investigating exact solutions of a generalized fractional nonlinear anomalousdiffusion equation in radical symmetry.The presence of external force and absorption is also considered.We firstinvestigate the nonlinear anomalous diffusion equations with one-fractional derivative and then multi-fractional ones.Inboth situations,we obtain the corresponding exact solutions,and the solutions found here can have a compact behavioror a long tailed behavior.展开更多
the Information-Centric Networking(ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations of ICN require changing the infrast...the Information-Centric Networking(ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations of ICN require changing the infrastructure of Internet, which hinders its deployment and development. Meanwhile, Software Defined Networking(SDN) emerges as a viable solution to facilitate the deployment of new network paradigm without disrupting production traffic by decoupling the control plane from data forwarding plane. In this paper, the essential properties which reflect ICN working principles are summarized, and a framework called SDICN is designed in accordance to the SDN philosophy. The algorithmic frameworks of SDICN which can satisfy the essential properties are designed based on the programmability and virtualization functions of SDN. Based on Open Flow and data center technology, a prototype of SDICN is implemented. By comparing the performance with the CCNx, the SDICN is proved to be feasibility and availability.展开更多
From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential ...From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value.展开更多
This paper discusses the issue of the hidden curriculum in the setting of a language classroom. The author first talks about the definition of the hidden curriculum from a theoretical perspective and proposes her own ...This paper discusses the issue of the hidden curriculum in the setting of a language classroom. The author first talks about the definition of the hidden curriculum from a theoretical perspective and proposes her own working definition. She then elaborates on the reasons and main manifestations of the hidden curriculum from the teachers' and learners' angles respectively with examples taken from language classrooms. Based on some profound reflections, some feasible suggestions on how to minimize the negative impacts of the hidden curriculum are suggested. On the basis of the previous discussion, the author reaches a conclusion: Language teachers should not avoid or ignore the hidden curriculum existing in the language teaching processes; rather, they are expected to face it positively and try their very best to solve the problems it brings. A sound attitude towards the hidden curriculum can help language teachers better understand and implement the formal or official curriculum made by the school or the state.展开更多
Paradise Lost is a great epic written by John Milton. Deeply influenced by Christian Humanism, Milton fully shows his free will defense in Paradise Lost. Based on the text of Paradise Lost, this paper mainly analyzes ...Paradise Lost is a great epic written by John Milton. Deeply influenced by Christian Humanism, Milton fully shows his free will defense in Paradise Lost. Based on the text of Paradise Lost, this paper mainly analyzes the causes of Milton's free will defense, his pursuit for free will shown in the two falls in the work: Satan's fall and Adam and Eve's fall. This paper also discusses the practical meaning of free will defense in Paradise Lost: it reveals his grief and anger of the failure of England revolution and shows the idea that people don't have the freedom to interfere or destroy other people's free will.展开更多
Objective:The aim of the study was to investigate the expressions of matrix metalloproteinase-2(MMP-2) and tissue inhibitor of MMP-2(TIMP-2) mRNA in transitional cell carcinomas of bladder and discuss their clinical s...Objective:The aim of the study was to investigate the expressions of matrix metalloproteinase-2(MMP-2) and tissue inhibitor of MMP-2(TIMP-2) mRNA in transitional cell carcinomas of bladder and discuss their clinical significances.Methods:Using RT-PCR and real time quantitative PCR(RQ-PCR) technique,the expressions of MMP-2 and TIMP-2 mRNA of 45 cases of bladder carcinoma(tumor group) and 10 cases of normal bladder tissue(control group) were analyzed.Results:MMP-2 and TIMP-2 were not expressed in control group.MMP-2 was expressed in 30 cases tumor samples and TIMP-2 was expressed in 26 cases.The expression of MMP-2 mRNA in non-muscle invasive bladder cancers and grade I cancers was lower than that in muscle invasive bladder cancers and grades II-III cancers respectively.The differences were statistically significant(P<0.05).The expression of MMP-2 in recurrent patients was higher than that in incipient patients.TIMP-2 mRNA expression decreased with grades and stage.The expression of TIMP-2 in non-muscle invasive bladder cancers and grade I cancers was higher than that in muscle invasive bladder cancers and grades II-III cancers respectively.There was statistical difference between two groups(P < 0.05).TIMP-2 expression in incipient patients was higher than that in recurrent patients,but the difference was not significant(P>0.05).Conclusion:These results suggest that MMP-2 and TIMP-2 play an important role in the invasion step of transitional cell carcinoma of bladder.MMP-2 may become a new approach to the diagnosis of bladder carcinoma.展开更多
Objective: To evaluate the expression and correlation of hypoxia inducible factor la (HIF-la) and vascular endothelial growth factor (VEGF) and Survivin proteins in biopsy specimens of esophageal squamous cell ca...Objective: To evaluate the expression and correlation of hypoxia inducible factor la (HIF-la) and vascular endothelial growth factor (VEGF) and Survivin proteins in biopsy specimens of esophageal squamous cell carcinoma (ESCC), and then determine whether the levels of expression of these proteins could predict the clinical effectiveness of radiotherapy in individual cancers. Methods: The expressions of HIF-IQ, VEGF and Survivin were shown by S-P immunohistochemical staining method in biopsy specimens of ESCC, which were obtained endoscopically from 50 patients before radiotherapy, and 10 cases of normal esophageal tissue. Results: The positive expression rates of H IF-IQ, VEGF and Survivin were 68%, 74% and 72% in ESCC respectively. However, the three tumor markers had negative expressions in normal esophageal tissue. The positive rate of HIF-IQ was positively correlated with VEGF and Survivin proteins. The positive rates of HIF-IQ and Survivin were closely related to the clinical stage, radiotherapy effectiveness and survival, otherwise, the expression of HIF-IQ was closely related to distant metastasis; both of them were no correlation with the differentiation degree of tumor. The effective rates of radiotherapy and mean survival periods of those cases with positive and negative expressions of HIF-IQ were 8.8%, 10 months and 81.25%, 25 months, respectively. The one, two, and three years survival rates of patients with positive and negative expressions of HIF-IQ were 38.2%, 5.9%, 2.9%, and 81.3%, 54.2%, 15.8%, respectively (P = 0.001). Patients with HIF-IQ positive expression obviously survived less than those with negative expression and the difference was significant. The expression of VEGF was only related to the distant metastasis. Conclusion: Over expressions of HIF-IQ, VEGF and Survivin were found in ESCC. The positive rate of HIF-IQ was positively correlated with VEGF and Survivin proteins. The expression of HIF-IQ may serve as an important parameter in evaluating response for radiotherapy and prognosis of ESCC. It may play an important role by up-regulating the transcription of VEGF and Survivin genes.展开更多
基金the National Natural Foundation of China (30400283)~~
文摘[ Objective] In order to study the relation between the HSPTO gene and male sterility of plant further. [ Methods ] Anther specific expression promoter Osg6B of rice was coloned by PCR then connected with HSP70 antisense fragment to construct HSPTO antisense expression vector. The expression vector was identified by PCR experiment and enzyme digestion. [ Result] The sequence of coloned Osg6B promoter had 97% homology to the published sequence, and the cis-regulatory element in promoter area was integrated. HSP70 antisense expression vector driven by the promoter Osg6B was confired by colony PCR and enzyme digestion. [ Conclusion] The construction of expression vector would lay solid foundation for utilization of genetic engineering male sterility of plant.
文摘Objective: To explore and investigate the selection of effective antisense oligodeoxynuleotides with the help of computer and RNAstructure folding software. Methods: Bcl-2 gene was used as the target gene and five antisense oligodeoxynuleotides were designed to be bound to Bcl-2 mRNA optimal secondary structure regions that were predicted free from intramolecular fold or instability of free energy. The five antisense oligodeoxynucleotides were studied with experimental assay of leukemia cells, including cell grow assay with tropan blue exclusion, expression of Bcl-2 protein detected with immunochemistry and flowcytometry, Bcl-2 mRNA content detected with RT-PCR technique, as well as apoptosis observed and determined with morphonological method, electrophoresis and flowcytometry. Results: The results showed that two of the five antisense oligodeoxynucleotides were effective antisense oligodeoxynucleotides, which were able to inhibit cell growth in leukemia, to decrease the level of Bcl-2 mRNA and protein, to induce apoptosis of leukemia cells significantly. Conclusion: The computational prediction of antisense efficacy is faster than other methods and more efficient, which can potentially speed the development of sequences for both research and clinical applications.
基金This project was supported by grants from Foundation of Science and Technology of Guangzhou city (2001-Z-037-01) and Guangdong Province (021195).
文摘Objective: To investigated the e?ect of inhibition of telomerase with hTERT antisense on leukemic cells (HL-60 and K562) to CDDP-induced apoptosis. Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and puri?ed. Telomerase activity was detected by Telomerase PCR ELASA kit and cell apoptosis was observed by morphological method and determined by ?owcytometry. Results: AS PS-ODN could signi?cantly inhibit telomerase activity by down regulat- ing the hTERT expression, and increase the susceptibility of leukemic cells to CDDP-induced apoptosis. Conclusion: Inhibition of telomerase with hTERT antisense can increases the susceptibility of leukemic cells to CDDP-induced apoptosis.
文摘cDNA encoding caffeoyl CoA O-methyltransferase (CCoAOMT) from Chinese white poplar ( Populus tomentosa Carr.) was cloned by RT-PCR and sequenced. Northern analysis displayed that the CCoAOMT was expressed specifically in the developing secondary xylem and its expression was coincident with lignification. The antisense CCoAOMT cDNA was transformed into P. tremula x P. alba mediated by Agrobacterium tumefaciens ( Smith et Townsend) Conn. Transgenic plants were identified with PCR, PCR-Southern and Southern analysis. Lignin content in 5- to 6-month-old transgenic plants was measured. One of the transgenic lines had significant reduction of 17.9% in Klason lignin content as compared with that of untransformed poplar. The results demonstrate that antisense repression of CCoAOMT is an efficient way to reduce lignin content for improving pulping property in engineered trees.
基金Supported by National Natural Science Foundation of China(30970247)Hunan Provincial Science Fund for Distinguished Young Scholars(11JJ1007)~~
文摘In order to create the Male Sterile Line in tobacco, the anti-sense fragment of HSP70 gene was linked to anther specific expression promoter TA29 and the reconstructed vector was transformed into tobacco by Agrobacterium mediated transformation, and the transformants were then screened. Gus and spot blotting hybridization analysis of the transformants indicated that anti-sense fragment of HSF70 gene had been integrated into tobacco genome and expressed, thus the male sterile tobacco line was obtained. Microscope observation of anther and pollen showed that pistils of transgenic tobacco were normal, whereas anthers and pollens were fairly abortive in the same transgenic tobacco flower, comparing with pistils and stamens in control plants. The ratio of HSI:'70 protein before and after heat shock in mitochondrial was found to be 1.39 in control tobacco plants and 1.01 in transgenic tobacco sterile lines. This is suggested that the anti-sense gene fragment of HSP70 can effectively inhibit the expression of HSP70 protein and lead to transgenic male sterility in tobacco flowers. The assay provided a new genetic engineering method for male sterility creation in plants.
文摘Objective: To evaluate three-dimensional bronchial artery imaging charactersin central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoreticalevidence on blood supply and intervention therapy. Methods: Eighteen patients with central lungcancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchialartery reconstruction was done at the console work-station. The space anatomical characters ofbronchial artery were observed through different rotations. Results: For 6 cases, thethree-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes(lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate ofbronchial arteries was the highest in pulmonary artery stricture and truncation groups, and thevessels' diameter became larger apparently. These characters demonstrated blood supply of this kindof central lung cancer come from bronchial artery. Volume rendering images were the best ones amongthree-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery canreveal the anatomical characters of bronchial artery and provide theoretical evidence on bloodsupply and intervention therapy of central lung cancer.
文摘Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense genes. Previ- ous studies have focused on the non-coding antisense genes, but the possible regulatory role of the antisense protein is poorly understood. In this study, we found that a protein encoded by the antisense gene ADF1 acts as a transcription suppressor, regulating the expression of sense gene MDF1 in Saccharomyces cerevisiae. Based on the evolutionary, ge- netic, cytological and biochemical evidence, we show that the protein-coding sense gene MDF1 most likely originated de novo from a previously non-coding sequence and can significantly suppress the mating efficiency of baker's yeast in rich medium by binding MATa2 and thus promote vegetative growth. These results shed new light on several im- portant issues, including a new sense-antisense interaction mechanism, the de novo origination of a functional gene, and the regulation of yeast mating pathway.
基金Supported by Ministry of Health of China,No.2008ZX10002-15National Natural Science Foundation of China,No.30921006+2 种基金Shanghai Science & Technology Committee,No.08XD14001Shanghai Board of Health,No.08GWD0208GWZX0201
文摘Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhH/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC- associated HBV mutants may not transmit via motherto-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic suscep-tibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active antiviral treatments.
基金Supported by The Department of Education of Zhejiang Province of China,grant No.Y200804314the Zhejiang Provincial Natural Science Foundation,grant No.R2090353+1 种基金the Department of Science and Technology of Zhejiang Province,grant No.2008C33039the Chinese Ministry of Health,grant No.N20100148
文摘AIM:To identify and assess mutations in the K-ras and BRAF genes in a cohort of Chinese patients with colorectal cancer (CRC) for their association with various clinicopathological parameters and prognosis.METHODS:Genomic DNA was isolated from frozen tissues.Pyrosequencing analysis was conducted to detect mutations in the K-ras (codons 12,13,and 61) and BRAF genes (codon 600).Statistical analysis was carried out using SPSS-15.0 software.RESULTS:Among the 118 colorectal cancer patients,we detected 41 (34.7%) mutations in the K-ras gene.Mutation frequencies at codon 12 and codon 13 were 23.7% (28/118) and 10.2% (12/118),respectively.Only one patient harbored a point mutation at codon 61 (0.8%,1/118).Gender was the only factor that showed an obvious relationship with K-ras gene mutation (female 44.7% vs male 28.2%,P=0.037).Other clinicopathological features,such as age,location of the tumor,tumor differentiation,Tumor,Node and Metastases classification,and the Union for International Cancer Control staging,showed no positive relationship with K-ras gene mutations.No significant correlation was observed between the presence of K-ras mutations (codons 12,13,and 61) and the survival of the patients.BRAF mutations were rare,and only two patients (1.7%) harbored a detectable mutation at codon 600.CONCLUSION:K-ras gene mutation is a common event in our 118 Chinese CRC patients,with an obvious relationship with gender.However,it seems not to be an independent prognostic factor in CRC patients.The BRAF gene is rarely mutated in Chinese CRC patients.
文摘Objective To investigate the expression of the preferentially expressed antigen of melanoma (PRAME) gene in acute leukemia and its clinical significance. Methods The level of expressed PRAME mRNA in bone marrow mononuclear cells from 34 patients with acute leukemia (AL) and in 12 bone marrow samples from healthy volunteers was measured via RT-PCR. Correlation analyses between PRAME gene expression and the clinical characteristics (gender, age, white blood count, immunophenotype of leukemia, percentage of blast cells, and karyotype) of the patients were performed. Results The PRAME gene was expressed in 38.2% of all 34 patients, in 40.7% of the patients with acute myelogenous leukemia (AML, n=27), and in 28.6% of the patients with acute lymphoblastic leukemia (ALL, n=7), but was not expressed in the healthy volunteers. The difference in the expression levels between AML and ALL patients was statistically significant. The rate of gene expression was 80% in M~, 33.3% in M2, and 28.6% in M~. Gene expression was also found to be correlated with CDl5 and CD33 expression and abnormal karyotype, but not with age, gender; white blood count or percentage of blast cells. Conclusions The PRAME gene is highly expressed in acute leukemia and could be a useful marker to monitor minimal residual disease. This gene is also a candidate target for the immunotherapy of acute leukemia.
基金Science and Technology of Guangzhou City (2001-Z-037-01)Guangdong Province (99M1204G)
文摘Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA) in K562 cellstreated with ASODN and hTERT mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results The hTERT mRNA level was decreased, and teloraerase activity was significantly inhibited when the K562 cells were treated withASODN for 48 h.Conclusion It is suggested that hTERT ASODN might specifically inhibit telomerase activity of K562 cells at translation level, and it isfurther proved that hTERT gene has significant correlation with telomerase activity.
基金Supported by National Natural Science Foundation of China under Grant No.60641006the National Science Foundation of Shandong Province under Grant No.Y2007A06
文摘This paper is devoted to investigating exact solutions of a generalized fractional nonlinear anomalousdiffusion equation in radical symmetry.The presence of external force and absorption is also considered.We firstinvestigate the nonlinear anomalous diffusion equations with one-fractional derivative and then multi-fractional ones.Inboth situations,we obtain the corresponding exact solutions,and the solutions found here can have a compact behavioror a long tailed behavior.
基金supported by the State Key Development Program for Basic Research of China under Grant No.2012CB315806National Natural Science Foundation of China(No.61379149,No.61402521 and No.61103225)+1 种基金Natural Science Foundation of Jiangsu(BK 20140070,BK20140068)Jiangsu Future Network Innovation Institute Research Project on Future Networks(BY2013095-1-06)
文摘the Information-Centric Networking(ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations of ICN require changing the infrastructure of Internet, which hinders its deployment and development. Meanwhile, Software Defined Networking(SDN) emerges as a viable solution to facilitate the deployment of new network paradigm without disrupting production traffic by decoupling the control plane from data forwarding plane. In this paper, the essential properties which reflect ICN working principles are summarized, and a framework called SDICN is designed in accordance to the SDN philosophy. The algorithmic frameworks of SDICN which can satisfy the essential properties are designed based on the programmability and virtualization functions of SDN. Based on Open Flow and data center technology, a prototype of SDICN is implemented. By comparing the performance with the CCNx, the SDICN is proved to be feasibility and availability.
基金Projects(51378131,51378403)supported by the National Natural Science Foundation of ChinaProject(2012210020203)supported by the Fundamental Research Funds for the Central Universities,China
文摘From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value.
文摘This paper discusses the issue of the hidden curriculum in the setting of a language classroom. The author first talks about the definition of the hidden curriculum from a theoretical perspective and proposes her own working definition. She then elaborates on the reasons and main manifestations of the hidden curriculum from the teachers' and learners' angles respectively with examples taken from language classrooms. Based on some profound reflections, some feasible suggestions on how to minimize the negative impacts of the hidden curriculum are suggested. On the basis of the previous discussion, the author reaches a conclusion: Language teachers should not avoid or ignore the hidden curriculum existing in the language teaching processes; rather, they are expected to face it positively and try their very best to solve the problems it brings. A sound attitude towards the hidden curriculum can help language teachers better understand and implement the formal or official curriculum made by the school or the state.
文摘Paradise Lost is a great epic written by John Milton. Deeply influenced by Christian Humanism, Milton fully shows his free will defense in Paradise Lost. Based on the text of Paradise Lost, this paper mainly analyzes the causes of Milton's free will defense, his pursuit for free will shown in the two falls in the work: Satan's fall and Adam and Eve's fall. This paper also discusses the practical meaning of free will defense in Paradise Lost: it reveals his grief and anger of the failure of England revolution and shows the idea that people don't have the freedom to interfere or destroy other people's free will.
文摘Objective:The aim of the study was to investigate the expressions of matrix metalloproteinase-2(MMP-2) and tissue inhibitor of MMP-2(TIMP-2) mRNA in transitional cell carcinomas of bladder and discuss their clinical significances.Methods:Using RT-PCR and real time quantitative PCR(RQ-PCR) technique,the expressions of MMP-2 and TIMP-2 mRNA of 45 cases of bladder carcinoma(tumor group) and 10 cases of normal bladder tissue(control group) were analyzed.Results:MMP-2 and TIMP-2 were not expressed in control group.MMP-2 was expressed in 30 cases tumor samples and TIMP-2 was expressed in 26 cases.The expression of MMP-2 mRNA in non-muscle invasive bladder cancers and grade I cancers was lower than that in muscle invasive bladder cancers and grades II-III cancers respectively.The differences were statistically significant(P<0.05).The expression of MMP-2 in recurrent patients was higher than that in incipient patients.TIMP-2 mRNA expression decreased with grades and stage.The expression of TIMP-2 in non-muscle invasive bladder cancers and grade I cancers was higher than that in muscle invasive bladder cancers and grades II-III cancers respectively.There was statistical difference between two groups(P < 0.05).TIMP-2 expression in incipient patients was higher than that in recurrent patients,but the difference was not significant(P>0.05).Conclusion:These results suggest that MMP-2 and TIMP-2 play an important role in the invasion step of transitional cell carcinoma of bladder.MMP-2 may become a new approach to the diagnosis of bladder carcinoma.
基金a grant from the tackle key problems in science andtechnology of Hebei Province(No.052761764).
文摘Objective: To evaluate the expression and correlation of hypoxia inducible factor la (HIF-la) and vascular endothelial growth factor (VEGF) and Survivin proteins in biopsy specimens of esophageal squamous cell carcinoma (ESCC), and then determine whether the levels of expression of these proteins could predict the clinical effectiveness of radiotherapy in individual cancers. Methods: The expressions of HIF-IQ, VEGF and Survivin were shown by S-P immunohistochemical staining method in biopsy specimens of ESCC, which were obtained endoscopically from 50 patients before radiotherapy, and 10 cases of normal esophageal tissue. Results: The positive expression rates of H IF-IQ, VEGF and Survivin were 68%, 74% and 72% in ESCC respectively. However, the three tumor markers had negative expressions in normal esophageal tissue. The positive rate of HIF-IQ was positively correlated with VEGF and Survivin proteins. The positive rates of HIF-IQ and Survivin were closely related to the clinical stage, radiotherapy effectiveness and survival, otherwise, the expression of HIF-IQ was closely related to distant metastasis; both of them were no correlation with the differentiation degree of tumor. The effective rates of radiotherapy and mean survival periods of those cases with positive and negative expressions of HIF-IQ were 8.8%, 10 months and 81.25%, 25 months, respectively. The one, two, and three years survival rates of patients with positive and negative expressions of HIF-IQ were 38.2%, 5.9%, 2.9%, and 81.3%, 54.2%, 15.8%, respectively (P = 0.001). Patients with HIF-IQ positive expression obviously survived less than those with negative expression and the difference was significant. The expression of VEGF was only related to the distant metastasis. Conclusion: Over expressions of HIF-IQ, VEGF and Survivin were found in ESCC. The positive rate of HIF-IQ was positively correlated with VEGF and Survivin proteins. The expression of HIF-IQ may serve as an important parameter in evaluating response for radiotherapy and prognosis of ESCC. It may play an important role by up-regulating the transcription of VEGF and Survivin genes.