Based on non-homogeneous model, a modified model is proposed. The new model deals with codon preference in protein-coding regions, reflects more accurately the key biological features of the regions. In addition, it i...Based on non-homogeneous model, a modified model is proposed. The new model deals with codon preference in protein-coding regions, reflects more accurately the key biological features of the regions. In addition, it is demonstrated, via an example, the modified model offers better solutions than previous model does.展开更多
AIM: To estimate the frequency of microdeletions in the long arm of Y-chromosome of 20 infertile males from South India. METHODS: Polymerase chain reaction (PCR) amplification using Y-specific STS of azoospermia facto...AIM: To estimate the frequency of microdeletions in the long arm of Y-chromosome of 20 infertile males from South India. METHODS: Polymerase chain reaction (PCR) amplification using Y-specific STS of azoospermia factor (AZF) regions i.e., SY 84 for AZFa, SY 127 for AZFb and SY 254 for AZFc. RESULTS: Of the 20 infertile subjects 3 (15 %), one azoospermic and two oligozoospermic, showed microdeletions in the AZF region of Y-chromosome. CONCLUSION: The frequency of deletions involving AZF region of the Y-chromosome is 15 % in azoospermic and severely oligozoospermic infertile men. PCR amplification of AZF locus is useful for the diagnosis of microdeletions in the Y-chromosome.展开更多
Nanopore-based sequencers, as the fourth-generation DNA sequencing technology, have the potential to quickly and reliably sequence the entire human genome for less than $1000, and possibly for even less than $100. The...Nanopore-based sequencers, as the fourth-generation DNA sequencing technology, have the potential to quickly and reliably sequence the entire human genome for less than $1000, and possibly for even less than $100. The single-molecule techniques used by this technology allow us to further study the interaction between DNA and protein, as well as between protein and protein.Nanopore analysis opens a new door to molecular biology investigation at the single-molecule scale.In this article, we have reviewed academic achievements in nanopore technology from the past as well as the latest advances, including both biological and solid-state nanopores, and discussed their recent and potential applications.展开更多
OBJECTIVE: To investigate the genotypes of hepatitis E viruses (HEV) detected in sera of patients from different regions of China. METHODS: The partial genome (nt6461-6860, nt5994-6294) of open reading frame 2 (ORF2) ...OBJECTIVE: To investigate the genotypes of hepatitis E viruses (HEV) detected in sera of patients from different regions of China. METHODS: The partial genome (nt6461-6860, nt5994-6294) of open reading frame 2 (ORF2) of 45 HEV strains detected from 14 cities of China was amplified and sequenced using polymerase chain reaction (PCR) and direct sequencing. RESULTS: Forty-one of 45 strains (91%) share the same genotype with HEV Burma strain (B), with nucleotide identities higher than 98% with the representative HEV Chinese strain. Only 4 HEV strains are significantly divergent from the 3 prototype strains of HEV, with nucleotide identities of 77%-80% with HEV Burmese/Chinese strain, 74%-76% with Mexican strain and 74%-77% with the newly discovered HEV US/swine strain, respectively. Phylogenetic analysis suggests that these 4 strains may represent 2 different subtypes that belong to a novel genotype of HEV, which is significantly divergent from the prototype Mexico, Burmese and US/swine strains. CONCLUSION: Among patients with hepatitis E in China, most are infected by the Chinese prototype HEV, and only a small part by the new genotype HEV.展开更多
文摘Based on non-homogeneous model, a modified model is proposed. The new model deals with codon preference in protein-coding regions, reflects more accurately the key biological features of the regions. In addition, it is demonstrated, via an example, the modified model offers better solutions than previous model does.
文摘AIM: To estimate the frequency of microdeletions in the long arm of Y-chromosome of 20 infertile males from South India. METHODS: Polymerase chain reaction (PCR) amplification using Y-specific STS of azoospermia factor (AZF) regions i.e., SY 84 for AZFa, SY 127 for AZFb and SY 254 for AZFc. RESULTS: Of the 20 infertile subjects 3 (15 %), one azoospermic and two oligozoospermic, showed microdeletions in the AZF region of Y-chromosome. CONCLUSION: The frequency of deletions involving AZF region of the Y-chromosome is 15 % in azoospermic and severely oligozoospermic infertile men. PCR amplification of AZF locus is useful for the diagnosis of microdeletions in the Y-chromosome.
基金supported by the National Natural Science Foundation of China–China(Grant No.61471336)the Joint-Scholar of West Light Foundation of the Chinese Academy of Sciences awarded to DW and Shanghai Synchrotron Radiation FacilityCY was supported by China Postdoctoral Science Foundation–China(Grant No.2014M551011)
文摘Nanopore-based sequencers, as the fourth-generation DNA sequencing technology, have the potential to quickly and reliably sequence the entire human genome for less than $1000, and possibly for even less than $100. The single-molecule techniques used by this technology allow us to further study the interaction between DNA and protein, as well as between protein and protein.Nanopore analysis opens a new door to molecular biology investigation at the single-molecule scale.In this article, we have reviewed academic achievements in nanopore technology from the past as well as the latest advances, including both biological and solid-state nanopores, and discussed their recent and potential applications.
基金supported in part by the National Major Projects of National Committee of Sciences and Technology ，People’s Republic of China (No．96-9 16-03-07)；China Medical Board， New York(No．93-582)．
文摘OBJECTIVE: To investigate the genotypes of hepatitis E viruses (HEV) detected in sera of patients from different regions of China. METHODS: The partial genome (nt6461-6860, nt5994-6294) of open reading frame 2 (ORF2) of 45 HEV strains detected from 14 cities of China was amplified and sequenced using polymerase chain reaction (PCR) and direct sequencing. RESULTS: Forty-one of 45 strains (91%) share the same genotype with HEV Burma strain (B), with nucleotide identities higher than 98% with the representative HEV Chinese strain. Only 4 HEV strains are significantly divergent from the 3 prototype strains of HEV, with nucleotide identities of 77%-80% with HEV Burmese/Chinese strain, 74%-76% with Mexican strain and 74%-77% with the newly discovered HEV US/swine strain, respectively. Phylogenetic analysis suggests that these 4 strains may represent 2 different subtypes that belong to a novel genotype of HEV, which is significantly divergent from the prototype Mexico, Burmese and US/swine strains. CONCLUSION: Among patients with hepatitis E in China, most are infected by the Chinese prototype HEV, and only a small part by the new genotype HEV.
