Objective :To evaluate the possibility of the technology involving PEP and RDB for detectingβ-thalassaemia multipoint mutations from a single cell simultaneously. Methods: A set of allele specific oligonucleotide (AS...Objective :To evaluate the possibility of the technology involving PEP and RDB for detectingβ-thalassaemia multipoint mutations from a single cell simultaneously. Methods: A set of allele specific oligonucleotide (ASO) probes used for detecting 8 familiarβ-thalassaemia mutations (CD41-42. IVS-Ⅱ-654, CD17, TATA box nt-28, CD71-72, TATA box nt-29, CD26, IVS-Ⅰ-5) were immobilized on a strip of nylon membrane. The genome of a individual cell was amplified by primer extension preamplification (PEP) with the mixture of 15-base random oligonucleotides. The aliquots from PEP were used to amplify the objective gene fractions ofβ-thalassaemia gene by nested or semi-nested PCR. The membrane was hybridized with the final amplified products and then treated with Streptavidin-HRP and color development. Results:Totally 30 lymphocytes were picked up from blood samples of 1 healthy female and 4 patients with knownβ-thalassaemia mutations respectively. Each single lymphocyte was lysed in the proteinase K buffer. The amplification efficacy was 94. 0% and alle drop-out (ADO) rate was 8. 0%. Revert dot blot (RDB) was applied to the final amplified products from the 5 participants. The results of diagnosis were the same to the expected, and their genotypes were N/N, CD17(A→T)/N, IVS-Ⅱ-654(C→T)/CD17(A→T), CD41-42(-CTTT)/N and TATA box nt-28(A→G)/N, respectively. Conclusion: The technology involving PEP and RDB could detect multipleβ-thalassaemia mutations from a single cell simultaneously, and the research provides experimental evidences for the feasibility of applying PEP and DNA array technology to screening multiple genetic mutations from a single cell, and will be applied to preimplantation genetic diagnosis and non-invasive prenatal diagnosis forβ-thalassaemia.展开更多
The mitochondrial cytochrome b gene was isolated from the caudal fin of Oryzias latipes and PCR was undertaken to determine phylogeny. The nucleotide sequence of the complete cytochrome b gene including the 5＇ and 3...The mitochondrial cytochrome b gene was isolated from the caudal fin of Oryzias latipes and PCR was undertaken to determine phylogeny. The nucleotide sequence of the complete cytochrome b gene including the 5＇ and 3＇ ends was 1,143 base pairs （bp） and 1,137 bp encoding 380 and 378 amino acids in the K-11 strain and HS strain, respectively. In addition, higher substitutions both in base and amino acid residues occurred more frequently between the former control （Hd-rR strain） and HS strains than the K-I 1 strain. Approximately similar values in polymorphism, as assessed by restriction endonuclease digestion, were detected when utilizing 20 different enzymes. Therefore, the evolutionary processes were unlikely to involve common ancestors, especially between the K-11 strain and HS strains, in O. latipes populations in Japan. The sequence had been deposited in GenBank Data Base under accession number AB480878 （K-I I strain） and AB480879 （HS strain）.展开更多
Space nuclear power system is the key technology for deep space exploration missions in the future, especially for space base building-up. This paper evaluates several typical latest space nuclear reactor system （SNR...Space nuclear power system is the key technology for deep space exploration missions in the future, especially for space base building-up. This paper evaluates several typical latest space nuclear reactor system （SNRS） designs, and finds that most of their weights are heavier than necessary. From the point of weight-control, the SA4 design is the best but its design is more complex than others. A newly designed SNRS, based on the SAFE400 model, uses annular fuel and has better performance, with a fuel mass lower than that of the SAFE400 prototype by 18.75%. Meanwhile, different from former opinions, the delay neutron fractions of SNRS are not constant and change with the different SNRS designs. Therefore, designs of SNRS not to count the delayed neutron fracture or directly to consider it as 0.00677 are not appropriate.展开更多
文摘Objective :To evaluate the possibility of the technology involving PEP and RDB for detectingβ-thalassaemia multipoint mutations from a single cell simultaneously. Methods: A set of allele specific oligonucleotide (ASO) probes used for detecting 8 familiarβ-thalassaemia mutations (CD41-42. IVS-Ⅱ-654, CD17, TATA box nt-28, CD71-72, TATA box nt-29, CD26, IVS-Ⅰ-5) were immobilized on a strip of nylon membrane. The genome of a individual cell was amplified by primer extension preamplification (PEP) with the mixture of 15-base random oligonucleotides. The aliquots from PEP were used to amplify the objective gene fractions ofβ-thalassaemia gene by nested or semi-nested PCR. The membrane was hybridized with the final amplified products and then treated with Streptavidin-HRP and color development. Results:Totally 30 lymphocytes were picked up from blood samples of 1 healthy female and 4 patients with knownβ-thalassaemia mutations respectively. Each single lymphocyte was lysed in the proteinase K buffer. The amplification efficacy was 94. 0% and alle drop-out (ADO) rate was 8. 0%. Revert dot blot (RDB) was applied to the final amplified products from the 5 participants. The results of diagnosis were the same to the expected, and their genotypes were N/N, CD17(A→T)/N, IVS-Ⅱ-654(C→T)/CD17(A→T), CD41-42(-CTTT)/N and TATA box nt-28(A→G)/N, respectively. Conclusion: The technology involving PEP and RDB could detect multipleβ-thalassaemia mutations from a single cell simultaneously, and the research provides experimental evidences for the feasibility of applying PEP and DNA array technology to screening multiple genetic mutations from a single cell, and will be applied to preimplantation genetic diagnosis and non-invasive prenatal diagnosis forβ-thalassaemia.
文摘The mitochondrial cytochrome b gene was isolated from the caudal fin of Oryzias latipes and PCR was undertaken to determine phylogeny. The nucleotide sequence of the complete cytochrome b gene including the 5＇ and 3＇ ends was 1,143 base pairs （bp） and 1,137 bp encoding 380 and 378 amino acids in the K-11 strain and HS strain, respectively. In addition, higher substitutions both in base and amino acid residues occurred more frequently between the former control （Hd-rR strain） and HS strains than the K-I 1 strain. Approximately similar values in polymorphism, as assessed by restriction endonuclease digestion, were detected when utilizing 20 different enzymes. Therefore, the evolutionary processes were unlikely to involve common ancestors, especially between the K-11 strain and HS strains, in O. latipes populations in Japan. The sequence had been deposited in GenBank Data Base under accession number AB480878 （K-I I strain） and AB480879 （HS strain）.
文摘Space nuclear power system is the key technology for deep space exploration missions in the future, especially for space base building-up. This paper evaluates several typical latest space nuclear reactor system （SNRS） designs, and finds that most of their weights are heavier than necessary. From the point of weight-control, the SA4 design is the best but its design is more complex than others. A newly designed SNRS, based on the SAFE400 model, uses annular fuel and has better performance, with a fuel mass lower than that of the SAFE400 prototype by 18.75%. Meanwhile, different from former opinions, the delay neutron fractions of SNRS are not constant and change with the different SNRS designs. Therefore, designs of SNRS not to count the delayed neutron fracture or directly to consider it as 0.00677 are not appropriate.
