Biomedical subjects

Ying-bi Li

Publications and source records attributed to Ying-bi Li.

13 recordsLinked to original sources

PubMed2006

[Constructing of STR slippage model by optimizing some factors].

OBJECTIVE: To construct STR slippage model and study factors involved in this procedure. METHODS: DNA samples were amplified with the technology of Degenerate oligonucleotide- primed PCR, then their products were taken as later DNA template and their STR genotype were analyzed by optimizing several factors. RESULTS: STR slippage model was constructed. CONCLUSION: Several factors were involved in the produce of STR slippage, such as amount of modulate DNA, concentration of MgCl2, property of DNA polymerase, motif sequence of STR loci, sample, etc.

DNA↗

PubMed2006

[Polymorphisms of seven short tandem repeat loci: D1S2142, D1S3733, D2S1774, D3S2459, D21S1409, D21S1437 and D21S2055 of Chinese Han population in Chengdu].

OBJECTIVE: To obtain the data in polymorphism distribution of the seven short tandem repeat (STR) loci: D1S2142, D1S3733, D2S1774, D3S2459, D21S1409, D21S1437 and D21S2055 of Chinese Han population in Chengdu, and evaluate the polymorphism data usefulness to the forensic science. METHODS: PCR, polyacrylamide gel electrophoresis (PAGE) and silver staining techniques were used to analyze the DNA samples from unrelated individuals of Chinese Han ethnic group in Chengdu. RESULTS: Eleven alleles and twenty-three genotypes were observed in D1S2142. Eight alleles and nineteen genotypes were observed in D1S3733. Eight alleles and fifteen genotypes were observed in D2S1774. Seven alleles and nineteen genotypes were observed in D3S2459. Six alleles and twelve genotypes were observed in D21S1409. Nine alleles and twenty-six genotypes were observed in D21S1437. Twenty alleles and seventy-seven genotypes were observed in D21S2055. The genotype distributions of the seven STR loci showed no deviation from the Hardy-Weinberg equilibrium. The parentage testing of 50 cases revealed an autosomal codominant inheritances and no mutations happened to seven STR loci. CONCLUSION: These data indicate that D1S2142, D1S3733, D2S1774, D3S2459, D21S1409, D21S1437 and D21S2055 have good polymorphism, with high probability of exclusion and probability of discrimination power as well as being loci available as the candidate genetic markers to forensic parentage testing and personal identification.

Alleles↗

PubMed2006

[Allele frequencies and species specificity of five short tandem repeat loci of Chinese Han population in Chengdu].

OBJECTIVE: To obtain the data in polymorphism distribution of the five short tandem repeat (STR) loci: D18S979, D11S2014, D18S548, D1S1667 and GATA164F07 of Chinese Han population in Chengdu, and to evaluate their usefulness in the field of species specificity in forensic science. METHODS: PCR, polyacrylamide gel electrophoresis (PAGE) and silver staining techniques were used to analyze the DNA samples from 100 unrelated individuals of Chinese Han ethnic group in Chengdu. Twelve different animals: monkey, pig, dog, bull, goat, chicken, duck, eel, mudfish, rabbit, guinea pig and mouse were selected as controls in this study for evaluating the species specificity of the five STR loci. RESULTS: Six alleles and twelve genotypes were observed in D18S979. Five alleles and eleven genotypes were observed in D11S2014. Five alleles and thirteen genotypes were observed in D18S548. Seven alleles and nineteen genotypes were observed in D1S1667. Six alleles and fourteen genotypes were observed in GATA164F07. The genotype distributions of the five loci were analyzed by some related software and no deviation from the Hardy-Weinberg equilibrium was observed. Evaluated by way of using different animals as controls, monkey had amplification products at the extra-typing field of D18S979, D11S2014 and D1S1667. Bull, dog and eel had amplification product at typing field of D18S979, and pig, duck, mouse and rabbit had weak product. Bull had weak product at the typing field of D18S548. Dog, goat and eel had product at the typing field of D1S1667. Dog had weak product at the typing field of GATA164F07. Mudfish, chicken and guinea pig had no amplification product at the five loci. CONCLUSION: These data indicate that D18S979, D18S548, D1S1667 and GATA164F07 are highly polymorphic and D11S2014, D18S548 and GATA164F07 can play a key role in species identification.

Animals↗

PubMed2005

[Constructing standard allelic ladders for four short tandem repeat loci and employing them in a population study on Han Nationality of Chengdu in China].

OBJECTIVE: To solve the problems in the accuracy and standardization of short tandem repeats-polymerase chain reaction (STR-PCR) typing, the authors adopted the molecular clone technology in producing the standard allelic ladders of D1S1676, D2S2735, D11S1977 and D22S444 loci and applied them in a population study on the Hans in Chengdu, China. METHODS: PCR was used to produce several different allelic fragments of these loci. PCR products were eluted from the gel and re-amplified by PCR. The purified allelic fragments were then blunt-end subcloned individually into the pGEMR-T plasmid vectors and the recombinant were transfected into competent E.coli DH5alpha TM cells. The results of sequencing confirmed that the size and the construction of the inserts were correct. The recombinant plasmids DNA with the inserts were then used as template for re-amplification to generate the four loci standard ladders. RESULTS: The authors succeeded in producing large quantity of standard allelic ladder of these four loci, with which the genetic polymorphisms of these loci in Chengdu Han population of China were studied. CONCLUSION: This method is of high value for forensic DNA typing to construct standard ladders. D1S1676, D2S2735 loci are robust for forensic analysis in Chinese Han population, whereas the value of D11S1977 and D22S444 loci is limited.

Alleles↗

PubMed2005

[Distribution of haplotypes for four Y-sTR loci and validation in forensic science by using a double-fluorescent multiplex PCR system].

OBJECTIVE: We focus on developing a multiplex PCR system for Y-STR loci that can be detected by double fluorescent system and assessing their usefulness in forensic mixture samples. METHODS: The primers of four Y-STR loci (DYS-GATA-A10, DYS531, DYS557 and DYS448) amplified by multiplex PCR technique were labeled with fluorescence, then the PCR products of these Y-STRs loci were detecting and typing by ABI PRISM310 Genetic Analyzer. RESULTS: When 120 unrelated individuals from the Han population in Chengdu were detected by the system, Y-GATA-A10, DYS531, DYS557 and DYS448 showed 5, 5, 8, 7 alleles, respectively. A total of 78 different haplotypes was identified and the genetic diversity reached 0.9881. To the three cases of mixture stains failed by using conventional autosomal STR analysis, our multiplex system drew conforming conclusion comparing to the suspect's Y-STRs genotypes. CONCLUSION: Our results show that the multiplex system of four Y-STR will be very powerful for Y-STR database establishing, the paternity testing and mixture stains identifying.

Alleles↗

PubMed2005

[The STR typing system by fluorescence labeled Multiplex-PCR technique and its forensic application].

OBJECTIVE: To build the four STR loci typing system by fluorescence labeled Multiplex-PCR technique, applied in the parentage test and personal identification in forensic medicine. METHODS: The primer of D3S1754 and D1S549 were labeled with 6-FAM and TMR respectively, primers of D4S2366 and D12S375 were labeled with HEX. Multiplex-PCR products were analysed on the ABI PRISM 310 Genetic Analyzer where the Data Collection Software 3.0, the GeneScan Analysis Software 3.7NT and the Genotyper 3.7NT Software were used. This typing system has been emploied in the parentage test and personal identification of casework. RESULTS: A method of typing four STR loci by fluorescence labeled Multiplex-PCR technique had been constructed. It has showed good sensitive and stability, and met the needs of parentage test and personal identification in forensic medicine. CONCLUSION: The constructed method can be used in studying genetic polymorphisms and parentage test or personal identification in forensic medicine.

DNA↗

PubMed2005

Effect of caspase 9 related signaling molecules on the apoptosis of human vascular endothelial cell induced by homocysteine.

OBJECTIVE: To understand the role of mitochondria associated signaling pathway in the apoptosis of human vascular endothelial cell induced by homocysteine (Hcy). METHODS: The mRNA and protein expression levels of the up-stream signaling molecules of caspase 3, Bcl 2, caspase 9, and cytosolic cytochrome-c, were investigated. The in vitro cultured human umbilical vein endothelial cells with homocysteine at different concentrations were incubated for 24 h. The expressions of Bcl 2 and caspase 9 at mRNA and protein levels were analyzed by reverse transcription-polymerase chain reaction(RT-PCR) and Western blot. Cytochrome-c in cytoplasm was also detected by Western blot. RESULTS: The expression levels of three signaling molecules were all down-regulated by homocysteine at both mRNA and protein levels in a dose-dependent manner. CONCLUSION: Homocysteine could affect the formation of apoptosome through repressing the expression of Bcl 2 gene and release of cytochrome-c from mitochondria. Decreasing of apoptosome could disturb the activation of caspase 9. The results also indicate that the mitochondria pathway is not the major signaling pathway involved in Hcy-induced apoptosis.

Apoptosis↗

PubMed2004

[Further study on heterogeneic basis of complement C8 beta deficiency].

OBJECTIVE: In Caucasian population, the most common molecular basis for C8 beta deficiency s a single C to T transition in exon 9 of C8 beta gene resulting in a stop codon. In previous family studies, two individuals were identified with C8 beta complete deficiency and were found to be only heterozygous for this mutation. This study was conducted by the present authors in search of other possible causes for these two C8 beta deficient individuals. METHODS: Using direct DNA sequence analysis of all exon-specific PCR products of the C8 beta gene from these two C8 beta deficient patients and their descendants. RESULTS: Two other C to T transitions at base 298 and 388 in exon 3 were detected, which could also create a termination codon. The descendants from one of the deficient patients were also analysed for the mutations, and it could be demonstrated that the two C to T mutations in exons 9 and 3 are segregating independently. CONCLUSION: These two mutations, which create a termination codon, are sufficient to explain the complete C8 beta deficiency in both patients.

Codon, Nonsense↗

PubMed2004

[Genetic polymorphisms of three STR loci on chromosome X and their forensic application in a Chinese Han population].

OBJECTIVE: To understand the allele structure and genetic polymorphism at three STR loci on chromosome X in Chinese Han population and make an evalution of their forensic application. METHODS: EDTA-blood samples were collected from the unrelated individuals in Chengdu, China. After being extracted with Chelex method, the DNA samples were amplified by PCR technique. The PCR products were analyzed by PAG electrophoresis and the approach of automated fluorescence detection. Hardy-Weinberg equilibrium of females was tested and every forensic interested value was calculated. RESULTS: The polymorphisms of all 3 STR loci were obtained from 100 unrelated females and 120 unrelated males from Chinese Han ethnic group. Chi-square tests on the genotype frequencies in females did not reveal deviations from Hardy-Weinberg equilibrium. CONCLUSION: The obtained data are beneficial to understanding the population genetics of the three STR loci in Chinese Han population. For forensic genetics, the obtained data can be used to calculate the probabilities dealing with the paternity test and the individual identification.

China↗

PubMed2004

[A study of quadriplex PCR with chimeric primers for short tandem repeats loci].

OBJECTIVE: To establish a simplified method of multiplex PCR based on chimeric primers for STR loci. METHODS: A set of chimeric primers and universal primers were designed to carry out a multiplex PCR for amplifying four short tandem repeats(STR) loci. Then the amplified STR loci were detected by polyacrylamide gel electrophoresis and the gels were sliverstained. RESULTS: A quadriplex STR system was developed on the basis of both chimeric and universal primers. CONCLUSION: The STR multiplex PCR based on both chimeric and universal primers hss been achieved readily and reproducibly by simple adjustment of the individual primer concentrations. The use of chimeric primers provides a method for primer design that eliminates the multiple optimization steps involved in developing the multiplex PCR.

DNA Primers↗

PubMed2004

[Study on association between aldosterone synthase gene polymorphism and the left ventricular structure and function of patients with dilated cardiomyopathy in China].

OBJECTIVE: To investigate the association between a -344 C/T polymorphism of aldosterone synthase gene (CYP11B2) and the left ventricular structure and function of patients with dilated cardiomyopathy (DCM) in China. METHODS: Eighty-nine patients with DCM were genotyped by PCR-RFLP, and were divided into TT, TC, CC and TT+CC four groups by their genotypes, respectively. Left ventricular structure and function were assessed with echocardiography. RESULTS: There was no significant difference between four groups in left ventricular diameters, mass and ejection fraction in patients with DCM. CONCLUSION: The data were not in favor of a significant association between the aldosterone synthase gene CYP11B2 and the left ventricular structure and function in patients with DCM.

Adult↗

PubMed2004

[Polymorphisms and species specificity of D2S2944 and D1S2134 loci in Chinese Han population in Chengdu].

OBJECTIVE: To obtain the data of polymorphism distribution of the two STR loci D2S2944, D1S2134 in Chinese Han population in Chengdu and evaluate their usefulness in the field of forensic science. METHODS: PCR, polyacrylamide gel electrophoresis (PAGE) and silver staining were used to analyze 120 unrelated individuals of Chinese Han ethnic group in Chengdu. Fourteen different animals: monkey, pig, dog, bull, goat, chicken, duck, fish, cat, rabbit, Guinea pig, mouse, eel and frog were selected as controls in this study for evaluating the species specificity of the two STR loci. RESULTS: Eight alleles and twenty-two genotypes were found in D2S2944. The observed heterozygosity (h), discrimination power (DP), polymorphism information content (PIC), chance of paternity exclusion power (EP) were 0.824, 0.925, 0.78, 0.644 respectively. Ten alleles and twenty-six genotypes were observed in D1S2134. The h, DP, PIC and EP were 0.769, 0.920, 0.79, 0.543 respectively. The genotype distributions of the two loci were analyzed by some related software and no deviation from the Hardy-Weinberg equilibrium was observed. Evaluated by way of using different animals as controls, the two STR loci of human beings were found to have good specificity. CONCLUSION: These data indicate that D1S2134 and D2S2944 are of good polymorphism, high EP and DP, and can be applied as the candidate genetic marks to forensic parentage testing and identification. The methods to analyze them are simple, dependable and repeatable.

Alleles↗

PubMed2004

[Allele frequencies and species specificity of six short tandem repeat loci in Chinese population].

OBJECTIVE: To develop a set of new markers for forensic application, the authors have chosen 6 short tandem repeat(STR) loci to study the allele frequencies and species specificity in Chinese Han population in Chengdu. METHODS: One hundred and ten EDTA-blood samples were collected from the unrelated individuals in Chengdu city, Sichuan province. DNA was extracted by Chelex-100 and amplified by the polymerase chain reaction(PCR). Polyacrylamide gel electrophoresis (PAGE) and silver staining were used to analyze the PCR products. RESULTS: The polymorphisms of all 6 STR loci have been obtained in Chinese Han population in Chengdu, the alleles of D4S2366, D4S2367, D6S474, D6S1281, D2S1396 and D20S601 being 7, 7, 6, 7, 5, 7, the observed heterozygosity of them being 0.802, 0.708, 0.770, 0.627, 0.542, 0.672, the discrimination power of them being 0.887, 0.828, 0.849, 0.848, 0.794, 0.865; and the power of exclusion of them being 0.602, 0.441, 0.544, 0.325, 0.227, 0.386. Evaluated by comparison with the data from 14 different animals as controls, the 6 STR loci contain good specificity of human beings. CONCLUSION: The 6 STR loci are highly polymorphic and can play a key role in species identification. They are new candidate markers for forensic personal identification and paternity testing.

Animals↗