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W-C Yang

Publications and source records attributed to W-C Yang.

10 recordsLinked to original sources
PubMed2006

Association evidence of schizophrenia with distal genomic region of NOTCH4 in Taiwanese families.

Evidence for association with schizophrenia has been reported for NOTCH4, although results have been inconsistent. Previous studies have focused on polymorphisms in the 5' promoter region and first exon of NOTCH4. Our aim was to test the association of the entire genomic region of NOTCH4 in 218 families with at least two siblings affected by schizophrenia in Taiwan. We genotyped seven single nucleotide polymorphisms (SNPs) of this gene, with average intermarker distances of 5.3 kb. Intermarker linkage disequilibrium (LD) was calculated using gold software, and single-locus and haplotype association analyses were performed using transmit software. We found that the T allele of SNP rs2071285 (P= 0.035) and the G allele of SNP rs204993 (P= 0.0097) were significantly preferentially transmitted to the affected individuals in the single-locus association analysis. The two SNPs were in high LD (D' > 0.8). Trend for overtransmission was shown for the T-G haplotype of the two SNPs to affected individuals (P= 0.053), with the A-A haplotype significantly undertransmitted (P= 0.034). The associated region distributed across the distal portion of the NOTCH4 gene and overlapped with the genomic region of the G-protein signaling modulator 3 and pre-B-cell leukemia transcription factor 2. In summary, we found modest association evidence between schizophrenia and the distal genomic region of NOTCH4 in this Taiwanese family sample. Further replication for association with the distal genomic region of NOTCH4 is warranted.

Gene Frequency↗
PubMed2006

Length polymorphism in heme oxygenase-1 is associated with arteriovenous fistula patency in hemodialysis patients.

Heme oxygenase-1 (HO-1) is a rate-limiting enzyme in heme degradation, producing carbon monoxide (CO), which carries potent antiproliferative and anti-inflammatory effects in the vascular walls. Transcription of the HO-1 gene is regulated by the length polymorphism of dinucleotide guanosine thymine repeat (GT)(n) in the promoter region, which was measured in this study to determine its association with arteriovenous fistula (AVF) failure in Chinese hemodialysis (HD) patients in Taiwan. L allele means (GT)(n)>or=30 and S allele means (GT)n<30. Therefore, there are two L alleles for L/L genotype, one L and one S allele for L/S genotype, and two S alleles for S/S genotype. Among the 603 HD patients who were enrolled in this study, 178 patients had history of AVF failure, while 425 patients did not. Significant associations were found between AVF failure and the following factors (hazard ratio): longer HD duration (1.004 month), lower pump flow (0.993 ml/min), higher dynamic venous pressure (1.010 mmHg), location of AVF on the right side (1.587 vs left side) and upper arm (2.242 vs forearm), and L/L and L/S genotypes of HO-1 (2.040 vs S/S genotype). The proportion of AVF failure increased from 20.3% in S/S genotype and 31.0% in L/S genotype to 35.4% in L/L genotype (P=0.011). Relative incidences were 1/87.6 (1 episode per 87.6 patient-months), 1/129, and 1/224.9 for HD patients with L/L, L/S, and S/S genotypes, respectively (P<0.002). The unassisted patency of AVF at 5 years decreased significantly from 83.8% (124/148) to 75.1% (223/297) and 69% (109/158) in S/S, L/S, and L/L genotypes, respectively (P<0.0001). In comparison with HD patients with S/S genotype, those with L/L genotype had a higher prevalence of coronary artery disease (29.1 vs 14.2%; P=0.005). A longer length polymorphism with (GT)(n) >or=30 in the HO-1 gene was associated with a higher frequency of access failure and a poorer patency of AVF in HD patients. The longer GT repeat in the HO-1 promoter might inhibit gene transcription, and consequently offset the CO-mediated protective effect against vascular injury.

Adult↗
PubMedDate not supplied

Applications of free-electron lasers in the biological and material sciences.

Free-Electron Lasers (FELs) collectively operate from the terahertz through the ultraviolet range and via intracavity Compton backscattering into the X-ray and gamma-ray regimes. FELs are continuously tunable and can provide optical powers, pulse structures and polarizations that are not matched by conventional lasers. Representative research in the biological and biomedical sciences and condensed matter and material research are described to illustrate the breadth and impact of FEL applications. These include terahertz dynamics in materials far from equilibrium, infrared nonlinear vibrational spectroscopy to investigate dynamical processes in condensed-phase systems, infrared resonant-enhanced multiphoton ionization for gas-phase spectroscopy and spectrometry, infrared matrix-assisted laser-desorption-ionization and infrared matrix-assisted pulsed laser evaporation for analysis and processing of organic materials, human neurosurgery and ophthalmic surgery using a medical infrared FEL and ultraviolet photoemission electron microscopy for nanoscale characterization of materials and nanoscale phenomena. The ongoing development of ultraviolet and X-ray FELs are discussed in terms of future opportunities for applications research.

Biology↗