Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by C Liao
Total Records ( 2 ) for C Liao
  J Jiang , N. L. S Tang , C Ohlsson , A. L Eriksson , L Vandenput , C Liao , X Wang , F. W. K Chan , A Kwok , E Orwoll , T. C. Y Kwok , J Woo and P. C. Leung
  BACKGROUND:

Results of recent studies have demonstrated that genetic variants of the enzyme steroid 5 reductase type II (SRD5A2) are associated with serum concentrations of major androgen metabolites such as conjugates of androstane-3,17β-diol-glucuronide (3-diol-G). However, this association was not consistently found among different ethnic groups. Thus, we aimed to determine whether the association with SRD5A2 genetic variations exists in a cohort of healthy Chinese elderly men, by examining 2 metabolite conjugates: androstane-3,l7β-diol-3-glucuronide (3-diol-3G) and androstane-3,17β-diol-17-glucuronide (3-diol-17G).

METHODS:

We used GC-MS and LC-MS to measure serum sex steroid concentrations, including testosterone and dihydrotestosterone, and 3-diol-3G and 3-diol-17G in 1182 Chinese elderly men age 65 and older. Genotyping of the 3 SRD5A2 tagSNPs [rs3731586, rs12470143, and rs523349 (V89L)] was performed by using melting-temperature–shift allele-specific PCR.

RESULTS:

The well-described SRD5A2 missense variant rs523349 (V89L) was modestly associated with the 3-diol-17G concentration (P = 0.040). On the other hand, SNP rs12470143 was found to be significantly correlated with 3-diol-3G concentration (P = 0.021). Results of haplotype analysis suggested that the presence of an A-C-G haplotype leads to an increased 3-diol-3G concentration, a finding consistent with results of single SNP analysis.

CONCLUSIONS:

The genetic variation of SRD5A2 is associated with circulating 3-diol-3G and 3-diol-17G concentrations in Chinese elderly men. In addition, we showed that SRD5A2 haplotypic association, rather than a single SNP alone, might be a better predictor of the 3-diol-G concentration. Thus, the effect of either the haplotype itself or of other ungenotyped SNPs in linkage disequilibrium with the haplotype is responsible for the interindividual variation of 3-diol-G.

  P Martinez , M Thanasoula , P Munoz , C Liao , A Tejera , C McNees , J. M Flores , O Fernandez Capetillo , M Tarsounas and M. A. Blasco
 

The telomere repeat-binding factor 1 (TERF1, referred to hereafter as TRF1) is a component of mammalian telomeres whose role in telomere biology and disease has remained elusive. Here, we report on cells and mice conditionally deleted for TRF1. TRF1-deleted mouse embryonic fibroblasts (MEFs) show rapid induction of senescence, which is concomitant with abundant telomeric -H2AX foci and activation of the ATM/ATR downstream checkpoint kinases CHK1 and CHK2. DNA damage foci are rescued by both ATM and ATM/ATR inhibitors, further indicating that both signaling pathways are activated upon TRF1 deletion. Abrogation of the p53 and RB pathways bypasses senescence but leads to chromosomal instability including sister chromatid fusions, chromosome concatenation, and occurrence of multitelomeric signals (MTS). MTS are also elevated in ATR-deficient MEFs or upon treatment with aphidicolin, two conditions known to induce breakage at fragile sites, suggesting that TRF1-depleted telomeres are prone to breakage. To address the impact of these molecular defects in the organism, we deleted TRF1 in stratified epithelia of TRF1/K5-Cre mice. These mice die perinatally and show skin hyperpigmentation and epithelial dysplasia, which are associated with induction of telomere-instigated DNA damage, activation of the p53/p21 and p16 pathways, and cell cycle arrest in vivo. p53 deficiency rescues mouse survival but leads to development of squamous cell carcinomas, demonstrating that TRF1 suppresses tumorigenesis. Together, these results demonstrate that dysfunction of a telomere-binding protein is sufficient to produce severe telomeric damage in the absence of telomere shortening, resulting in premature tissue degeneration and development of neoplastic lesions.

 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility