Interleukin gene polymorphisms in age-related macular degeneration

[[abstract]]PURPOSE. To investigate polymorphisms in a candidate gene of interleukin (IL) in unrelated Taiwan Chinese patients with late age-related macular degeneration (AMD) and control subjects without AMD. METHODS. In this retrospective, case-control study, 312 unrelated Taiwan Chinese patients with late AMD and 180 age- and sex-matched control subjects were enrolled. Late AMD was classified as either atrophic (dry) or neovascular (wet) according to the International ARM Epidemiologic Study. Genomic DNA was prepared from peripheral blood obtained from all patients with AMD and control subjects. Polymerase chain reactions were used to analyze 14 single-nucleotide polymorphisms (SNPs) in candidate genes of 5 ILs: IL-1 beta(2q14): -511 T/C; IL-6 (7p21): -572 C/G and -596 G/A; IL-8 (4q13-q21): -251 A/T, +781 C/T, +1633 T/C, and +2767 A/T; IL-10 (1q31-q32): -592 A/C, -819 C/T, and -1082 G/A; and IL-18 (11q22.2-q22.3): +105 A/C, -137 C/G, -607 A/C, and -656 T/G. RESULTS. In the 312 patients with late AMD, dry AMD was diagnosed in 136 and wet AMD in 176. Among the 14 SNPs in the 5 IL genes studied, only the IL-8 +781 C/T SNP was significantly associated with wet AMD (T allele: 46% in wet AMD versus 28% in the control subjects, P = 1.03 x 10(-6), OR = 2.16, 95% CI = 1.58-2.94). The association analysis based on genotypes at both IL-8 +781 C/T and the CFH Y402H demonstrated that the IL-8 +781 C/T to AMD was not significant when analyzed conditional on the presence of the CFH Y402H C risk allele and vice versa. The IL-8 +781 C/T was in low linkage disequilibrium with CFH Y402H (D' = 0.02). CONCLUSIONS. The data suggest that Taiwan Chinese carriers of the IL-8 +781 T allele, independent of the CFH Y402H polymorphism, are at increased risk of developing wet AMD

Vascular endothelial growth factor gene 460 polymorphism is associated with pterygium formation in female patients

[[abstract]]Purpose: Pterygium is composed of proliferating fibrovascular tissue, and its formation and progression require neovascularization. Vascular endothelial growth factor (VEGF) is a specific mitogen for vascular endothelial cells and is essential for neovascularization. Recently, the VEGF-460 polymorphism was reported to be associated with increased VEGF basal promoter activity and with several fibrovascular diseases, such as proliferative diabetic retinopathy, endometriosis, and chronic renal disease. Therefore, this study evaluated the potential association between pterygium formation and VEGF-460 polymorphism. Methods: One hundred twenty-seven pterygium patients and 102 volunteers without pterygium were enrolled in this study. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to resolve the VEGF-460 genotypes of pterygium patients and normal controls. Results: There were no significant differences between pterygium and control groups in age, sex, and distribution of genotype and allelic frequency of VEGF-460 polymorphism. However, when results were stratified by sex, there were significant differences between female patients and controls in the distribution of genotype and allelic frequency of VEGF-460 polymorphism. Females who carried at least 1 C allele (C/C and C/T genotypes) had about a 2.5-fold increased risk of developing pterygium compared with those who carried the T/T genotype, and there was a significantly higher frequency of C/C and C/T genotypes in younger female patients than in older female patients. There were no differences between male patients and controls in the distribution of genotype and allelic frequency of the VEGF-460 polymorphism. Conclusions: VEGF-460C polymorphism is associated with pterygium formation in female patients. Females who carried the C allele have increased risk of developing pterygium at a younger age

Evidence for non-self-similarity of microearthquakes recorded at a Taiwan borehole seismometer array

We investigate the relationship between seismic moment M0 and source duration tw of microearthquakes by using high-quality seismic data recorded with a vertical borehole array installed in central Taiwan. We apply a waveform cross-correlation method to the three-component records and identify several event clusters with high waveform similarity, with event magnitudes ranging from 0.3 to 2.0. Three clusters—Clusters A, B and C—contain 11, 8 and 6 events with similar waveforms, respectively. To determine how M0 scales with tw, we remove path effects by using a path-averaged Q. The results indicate a nearly constant tw for events within each cluster, regardless of M0, with mean values of tw being 0.058, 0.056 and 0.034 s for Clusters A, B and C, respectively. Constant tw, independent of M0, violates the commonly used scaling relation tw∝M1/30tw∝M01/3. This constant duration may arise either because all events in a cluster are hosted on the same isolated seismogenic patch, or because the events are driven by external factors of constant duration, such as fluid injections into the fault zone. It may also be related to the earthquake nucleation size

IN-SITU RAMAN-SPECTROSCOPIC STUDY OF OXYGEN ADSPECIES ON A TH-LA-O-X CATALYST FOR METHANE OXIDATIVE COUPLING REACTION

The superoxide adspecies O-2(-) is identified by in situ Raman spectroscopy on a functioning Th-La-O-x catalyst for methane oxidative coupling reaction at 680-860 degrees C

Genetic polymorphisms of DNA double strand break gene Ku70 and gastric cancer in Taiwan

<p>Abstract</p> <p>Background and aim</p> <p>The DNA repair gene <it>Ku70</it>, an important member of non-homologous end-joining repair system, is thought to play an important role in the repairing of DNA double strand breaks. It is known that defects in double strand break repair capacity can lead to irreversible genomic instability. However, the polymorphic variants of <it>Ku70</it>, have never been reported about their association with gastric cancer susceptibility.</p> <p>Methods</p> <p>In this hospital-based case-control study, the associations of <it>Ku70 </it>promoter T-991C (rs5751129), promoter G-57C (rs2267437), promoter A-31G (rs132770), and intron 3 (rs132774) polymorphisms with gastric cancer risk in a Taiwanese population were investigated. In total, 136 patients with gastric cancer and 560 age- and gender-matched healthy controls recruited from the China Medical Hospital in Taiwan were genotyped.</p> <p>Results</p> <p>As for <it>Ku70 </it>promoter T-991C, the ORs after adjusted by age and gender of the people carrying TC and CC genotypes were 2.41 (95% CI = 1.53-3.88) and 3.21 (95% CI = 0.96-9.41) respectively, compared to those carrying TT wild-type genotype. The <it>P </it>for trend was significant (<it>P </it>< 0.0001). In the dominant model (TC plus CC versus TT), the association between <it>Ku70 </it>promoter T-991C polymorphism and the risk for gastric cancer was also significant (adjusted OR = 2.48, 95% CI = 1.74-3.92). When stratified by age and gender, the association was restricted to those at the age of 55 or elder of age (TC vs TT: adjusted OR = 2.52, 95% CI = 1.37-4.68, <it>P </it>= 0.0139) and male (TC vs TT: adjusted OR = 2.58, 95% CI = 1.33-4.47, <it>P </it>= 0.0085). As for the other three polymorphisms, there was no difference between both groups in the distributions of their genotype frequencies.</p> <p>Conclusion</p> <p>In conclusion, the <it>Ku70 </it>promoter T-991C (rs5751129), but not the <it>Ku70 </it>promoter C-57G (rs2267437), promoter A-31G (rs132770) or intron 3 (rs132774), is associated with gastric cancer susceptibility. This polymorphism may be a novel useful marker for gastric carcinogenesis.</p

Structural Characterization of Mesoporous Silica Nanofibers Synthesized Within Porous Alumina Membranes

Mesoporous silica nanofibers were synthesized within the pores of the anodic aluminum oxide template using a simple sol–gel method. Transmission electron microscopy investigation indicated that the concentration of the structure-directing agent (EO20PO70EO20) had a significant impact on the mesostructure of mesoporous silica nanofibers. Samples with alignment of nanochannels along the axis of mesoporous silica nanofibers could be formed under the P123 concentration of 0.15 mg/mL. When the P123 concentration increased to 0.3 mg/mL, samples with a circular lamellar mesostructure could be obtained. The mechanism for the effect of the P123 concentration on the mesostructure of mesoporous silica nanofibres was proposed and discussed

Androgen receptor signalling in Vascular Endothelial cells is dispensable for spermatogenesis and male fertility

<p>Abstract</p> <p>Background</p> <p>Androgen signalling is essential both for male development and function of the male reproductive system in adulthood. Within the adult testis, Germ cells (GC) do not express androgen receptor (AR) suggesting androgen-mediated promotion of spermatogenesis must act via AR-expressing somatic cell-types. Several recent studies have exploited the Cre/lox system of conditional gene-targeting to ablate AR function from key somatic cell-types in order to establish the cell-specific role of AR in promotion of male fertility. In this study, we have used a similar approach to specifically ablate AR-signalling from Vascular Endothelial (VE) cells, with a view to defining the significance of androgen signalling within this cell-type on spermatogenesis.</p> <p>Findings</p> <p>AR expression in VE cells of the testicular vasculature was confirmed using an antibody against AR. A Cre-inducible fluorescent reporter line was used to empirically establish the utility of a mouse line expressing Cre Recombinase driven by the Tie2-Promoter, for targeting VE cells. Immunofluorescent detection revealed expression of YFP (and therefore Cre Recombinase function) limited to VE cells and an interstitial population of cells, believed to be macrophages, that did not express AR. Mating of Tie2-Cre males to females carrying a floxed AR gene produced Vascular Endothelial Androgen Receptor Knockout (VEARKO) mice and littermate controls. Ablation of AR from all VE cells was confirmed; however, no significant differences in bodyweight or reproductive tissue weights could be detected in VEARKO animals and spermatogenesis and fertility was unaffected.</p> <p>Conclusions</p> <p>We demonstrate the successful generation and empirical validation of a cell-specific knockout of AR from VE cells, and conclude that AR expression in VE cells is not essential for spermatogenesis or male fertility.</p

Fluorescence Quenching of Alpha-Fetoprotein by Gold Nanoparticles: Effect of Dielectric Shell on Non-Radiative Decay

Fluorescence quenching spectrometry was applied to study the interactions between gold colloidal nanoparticles and alpha-fetoprotein (AFP). Experimental results show that the gold nanoparticles can quench the fluorescence emission of adsorbed AFP effectively. Furthermore, the intensity of fluorescence emission peak decreases monotonously with the increasing gold nanoparticles content. A mechanism based on surface plasmon resonance–induced non-radiative decay was investigated to illuminate the effect of a dielectric shell on the fluorescence quenching ability of gold nanoparticles. The calculation results show that the increasing dielectric shell thickness may improve the monochromaticity of fluorescence quenching. However, high energy transfer efficiency can be obtained within a wide wavelength band by coating a thinner dielectric shell