Charge separation in donor-acceptor spiro compounds at metal and metal oxide surfaces investigated by surface photovoltage

Molecules with donor (diphenylamine) and acceptor moieties (dicyano or cyanoacrylic acid moieties) were linked by fluorene or spirobisfluorene cores and the chain length has been changed by introducing a thiophene group between fluorene and diphenylamine. Four different kinds of fluorene and spirobisfluorene compounds were adsorbed from highly diluted solutions at ultra-thin nanoporous TiO2 (np-TiO2), Au and ITO surfaces. Charge separation has been investigated by surface photovoltage spectroscopy in the fixed capacitor and Kelvin probe arrangements in vacuum. Striking differences between the interaction of linking (dicyano or cyanoacrylic moieties) and different substrates were observed. Intra-molecular charge separation and electron injection have been distinguished and the directed adsorption of spiro compounds was deduced.

Genetic variability in copper-transporting P-type adenosine triphosphatase (ATP7B) is associated with Alzheimer's disease in a Chinese population

Previous experiments demonstrated that transgenic mice carrying both amyloid precursor protein and mutant ATP7B transgenes reduce amyloid plaques and diminish plasma Abeta levels. These experiments showed that a structural change of ATP7B may affect Alzheimer’s disease (AD) susceptibility. In this study three missense SNPs in ATP7B gene (rs1801243, rs1801244, and rs1801249) were chosen to test whether they were associated with AD. We tested this hypothesis using a case control design. The experimental data showed that there was a significant deviation from Hardy-Weinberg equilibrium (HWE) for SNP rs1801249 (c.3419 T greater than C, Val1140Ala) in the case group (p = 0.014) but not in the control group and that there was an association between SNP rs1801249 and AD under a recessive model (p = 0.003). The data also showed that the genotype frequency distribution of the ATP7B c.1366 G greater than C polymorphism (rs1801244, Val456Leu) differed significantly between the AD patients and the normal subjects (p = 0.012). In addition, the frequency of the TGC haplotype of SNPs rs1801243, rs1801244, and rs1801249 was significantly higher in the AD patients compared with the normal subjects (p = 8.49×10-7). These observations suggested that genetic variations in the copper transporter gene ATP7B might contribute to AD pathogenesis in the Taiwanese population.

Metallothionein 1A polymorphisms may influence urine uric acid and N-acetyl-beta-D-glucosaminidase (NAG) excretion in chronic lead-exposed workers

Lead is a renal toxin, and susceptibility to lead varies between individuals. Metallothionein (MT) is known for its metal scavenging role. The aim of the study was to investigate the association of blood lead levels, urinary uric acid (UA) and N-acetyl-beta-d-glucosaminidase (NAG) in chronic occupational lead-exposed workers, and to study whether the association was influenced by MT1A gene polymorphisms. In this cross-sectional study, 412 lead-exposed workers participated. Their annual health examination data and renal function markers were collected after the Institutional Review Broad of Kaohsiung Medical University Hospital approved the study and consent letters were obtained. From the blood samples, DNA was extracted and used for real-time PCR typing of 2 MT1A single nucleotide polymorphisms (SNPs): rs11640851 and rs8052394 on exons 2 and 3. Descriptive analysis, one-way ANOVA, and multiple linear regressions were performed. There was a significant inverted relationship of creatinine-adjusted urine UA concentrations and the time-weighted index of cumulative blood lead levels (TWICL) that may be significantly influenced by the AC genotypes of rs11640851 in exon 2 and rs8052394 in exon 3. After controlling for potential confounding factors, the creatinine-adjusted urine NAG concentrations were shown to be influenced by the GG genotype of rs8052394 in exon 3, and were weakly increased with TWICL. Therefore, we concluded that the variations of MT1A SNPs may influence urine UA and NAG excretion in chronic lead-exposed workers, and urine creatinine-adjusted urine UA as a biomarker of lead toxicity should be considered.

Association analysis of dopaminergic gene variants (Comt, Drd4 And Dat1) with Alzheimer s disease

Defects in dopaminergic transmission play important roles in the disturbance of synaptic plasticity and even in advanced cognitive behavior. However, the relationship between genes involved in the regulation of dopamine levels and predisposition for Alzheimer s disease (AD) remains unclear. The potential association of dopamine-modulating gene polymorphisms with AD was evaluated. We performed a case-control study with 120 patients and 86 healthy controls. Two catechol-O-methyltransferase (COMT) single-nucleotide polymorphisms (SNPs) (rs2020917 and rs4646312), two dopamine D4 receptor (DRD4) SNPs (rs3758653 and rs916455), and four dopamine transporter (DAT1) SNPs (rs2937639, rs6347, rs12516948 and rs11133762) were investigated. The T allele at the DRD4 SNP (rs3758653) was found to be significantly associated with AD. Our results also showed that haplotype frequencies, observed from the analyzed SNPs, were distributed significantly differently in AD patients vs control subjects. Moreover, a strong association was observed between the A allele at rs6347 of DAT1 and moderate stage of dementia. These observations suggest that genetic variations in the dopamine-modulating genes, COMT, DRD4 and DAT1, may contribute to AD pathogenesis in the Taiwanese population.

Remodeling of rabbit abdominal aorta and Cx43 gap junctions after stent placement: effect of balloon injury plus cholesterol-enriched diet

AIM

To examine the effect of stenting and cholesterol-enriched diet (CED) on vascular remodeling, including the expression of connexin43 (Cx43) gap junctions in smooth muscle cells (SMC).

METHODS

Rabbits abdominal aortae were either implanted stent made of 316 stainless steel (group 1) or denuded followed by stent placement 28 days later (groups 2 and 3). Animals were given normal chow except those of group 3, which were fed CED after the denudation. Eight weeks later, the development of neointima and the expression of connexin43 (Cx43) were examined. In parallel, human aortic SMC were grown on 316 stainless steel or treated with C-reactive protein (CRP) followed by analysis of Cx43.

RESULTS

The results showed that, serum CRP levels became transiently elevated after denudation and stent implantation. For the stented aortic segments, the dimensions of neointima were group 3 > group 2 > group 1 (P<0.05). In groups 1 and 2, Cx43 gap junctions are less in amount in neointima of the stented segment, compared to the unstented upstream neointima or medial layer (all P<0.01). In culture experiments, Cx43 in SMC grown on stent material was up-regulated in growth medium but down-regulated in differentiation medium, and CRP did not affect Cx43 expression.

CONCLUSION

Vascular remodeling post stent implantation varied according to the presence of balloon injury, CED, or both. Cx43 expression in SMC is altered after exposure to stent and the regulation depended on the milieu.

Matrix metalloproteinase-12 leads to elastin degradation in BALB/c mice with eosinophilic meningitis caused by Angiostrongylus cantonensis

The rat lugworm Angiostrongylus cantonensis can cause eosinophilic meningitis. The purpose of this study was to determine whether matrix metalloproteinase (MMP)-12 and its substrate elastin participate in this inflammatory response. We showed that the MMP-12/tissue inhibitor of metalloproteinase-1 ratio was significantly increased in the CSF of A. cantonensis-infected mice from day 10 p.i., and reached high levels on days 20 and 25 p.i. MMP-12 production was correlated with elastin degradation, eosinophil count, blood-CSF barrier permeability and pathological changes in the subarachnoid space. Also, MMP-12 might contribute to elastin degradation in the meningeal vessel of the subarachnoid space. Simultaneous administration of albendazole and doxycycline significantly reduced the levels of MMP-12, elastin and Evans blue in mice with meningitis. These results imply that MMP-12 contributes to the elastin degradation that occurs in angiostrongyliasis meningitis, and doxycycline can reverse related inflammatory events by inhibition of MMP-12.

Genetic polymorphisms of the DNA repair gene MPG may be associated with susceptibility to rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease and can lead to deformities and severe disabilities, due to irreversible damage of tendons, joints, and bones. A previous study indicated that a DNA repair system was involved in the development of RA. In this study, we investigated the association of four N-methylpurine-DNA glycosylase (MPG) gene polymorphisms (rs3176364, rs710079, rs2858056, and rs2541632) with susceptibility to RA in 384 Taiwanese individuals (192 RA patients and 192 control subjects). Our data show a statistically significant difference in genotype frequency distributions at rs710079 and rs2858056 SNPs between RA patients and control groups (P = 0.040 and 0.029, respectively). Our data also indicated that individuals with the GG genotype at rs2858056 SNP may have a higher risk of developing RA. In addition, compared with the haplotype frequencies between case and control groups, individuals with the GCGC haplotype appeared to be at a greater risk of RA progression (P = 0.003, OR = 1.75; 95&percnt; CI = 1.20-1.55). Our results suggest that rs710079 and rs2858056 polymorphisms and the GCGC haplotype in the MPG gene are associated with the risk of RA progression, and thus may be used as molecular markers of RA if they are confirmed by further research.

Faceted ice growth in hydrophilic and hydrophobic channels

This study is motivated by the cryo-preservation for tissues, which is related to the solidification of blood in a confined space. The morphological behavior of growing ice facet in 1.3 mm hydrophilic and hydrophobic channels is the focus of this study. Both DI water and KCl solution were solidified without seeds in the channels and the growing front facet was discussed in regards to contact angle, in-situ morphology, conductivity difference between two phases and solute segregation. For DI water, the formation of facets was observed during ice growth in both hydrophilic and hydrophobic channels and could be classified into two modes according to the local curvature of the interface. The facet was formed at different positions of the interface in hydrophilic and hydrophobic channels. Solutal segregation effect was taken into consideration to partially govern the interface morphology and the facet formation during solidification of the KCl solution. In addition, the growth rates of the ice growth with a facet were also compared and discussed.

The involvement of insulin receptor genotypes in pre- and co-obese acanthosis Nigricans children and adolescent

Acanthosis nigricans (AN) is most commonly related to obesity as a manifestation of cutaneous insulin resistance in children and adolescents, while the interaction and time course between AN and obesity and detailed mechanism for the pre- and co-obese appearance of AN (PCOAN) in child are unclear. In this study, the involvement of insulin receptor in child PCOAN was investigated via studying the association of polymorphisms of INSR gene with PCOAN. In total, 99 children with PCOAN and 100 healthy controls recruited were genotyped and analyzed by PCR-RFLP method. Significantly different distributions were found in the frequency of the INSR His1085His genotypes, but not in other INSR genotypes, between the two groups. Our results provide not only the evidence that the T allele of INSR His1085His is correlated with the appearance of PCOAN but revealed that the insulin receptor pathway may play an important role in this PCOAN.

Analysis of ERCC2/XPD functional polymorphisms in systemic lupus erythematosus

Sunlight/ultraviolet (UV) irradiation has been recognized as an important risk factor for developing systemic lupus erythematosus (SLE). However, the interpretation of genetic variations involved in UV-light sensitivity is largely unknown. Recent studies indicated that two genetic variations of ERCC2/XPD gene (rs1799793 in exon 10 and rs13181 in exon 23) have been found to exert negative influences on nucleotide excision repair system. To analyse the possible contribution of the ERCC2/XPD functional single nucleotide polymorphisms in genetic susceptibility to SLE, the rs13181 and rs1799793 SNPs in ERCC2/XPD were genotyped by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Association was studied by case-control analyses using samples from 172 SLE patients and 160 healthy controls. Haplotype analysis was performed to detect the association with genetic predisposition to SLE and the clinical features. Although these two functional genetic variations are linked to several immune dysfunction-induced diseases, no statistically significant differences in allele or genotype frequencies were observed between SLE patients and controls. Haplotype analysis showed that none of ERCC2/XPD haplotypes was associated with the incidence of SLE disease, nor the preference of clinical features. In conclusion, the ERCC2/XPD functional polymorphisms analysed in this study showed no association in genetic susceptibility to SLE.