Efficacy and safety of teneligliptin, a dipeptidyl peptidase-4 inhibitor, combined with metformin in Korean patients with type 2 diabetes mellitus: a 16-week, randomized, double-blind, placebo-controlled phase III trial

The aim of the present study was to assess the efficacy and safety of teneligliptin in combination with metformin in Korean patients with type 2 diabetes mellitus who were inadequately controlled with metformin monotherapy. Patients [glycated haemoglobin (HbA1c) 7.0-10.0%, on stable metformin ≥1000 mg/day] were randomized 2 : 1 to receive 20 mg teneligliptin plus metformin (n = 136) or placebo plus metformin (n = 68). The primary endpoint was the change in HbA1c levels from baseline to week 16. The mean baseline HbA1c was 7.9% in the teneligliptin group and 7.8% in the placebo group. The differences between the teneligliptin and placebo groups regarding changes in HbA1c and fasting plasma glucose levels were -0.78 % and -1.24 mmol/l (22.42 mg/dl), respectively, at week 16. The incidence of adverse events was similar between the groups. The addition of teneligliptin once daily to metformin was effective and generally well tolerated in Korean patients with type 2 diabetes.

Uncertain areas in the diagnosis of allergic bronchopulmonary aspergillosis in patients with asthma

BACKGROUND AND OBJECTIVE

The prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients with bronchial asthma remains unknown. We evaluated the roles of various laboratory tests in the diagnosis of ABPA, including, skin prick test (SPT) for Aspergillus fumigatus (Af), and serum Af specific IgE and IgG antibody measurement.

METHODS

A total of 50 asthma patients with more than 1000cell/μL of peripheral blood eosinophils were prospectively collected between January 2007 and September 2011. Evaluations using SPT for Af, serum total IgE and specific IgE antibody to Af by CAP system, IgG antibody to Af by enzyme immunoassay (EIA) or CAP system were performed according to the essential minimal criteria for the diagnosis of ABPA - asthma, immediate cutaneous reactivity to Af, elevated total IgE, and raised Af specific IgE and IgG.

RESULTS

Among 50 patients, three patients (6.0%) were diagnosed as ABPA, of whom each confirmed five items of the essential minimal diagnostic criteria for the diagnosis of ABPA. Six patients (12.0%) showed negative responses to Af in SPT, but positive responses in specific IgE by CAP system. Eight patients (16.0%) showed negative responses to IgG to Af by CAP system, but positive responses by enzyme immunoassay (EIA).

CONCLUSIONS

SPT and serum IgE to Af measurement by CAP system should be performed simultaneously. It is reasonable to set up cut-off values in Af specific IgE/IgG by CAP system for the differentiation of ABPA from Af sensitised asthma patients.

Effect of an organic buffer layer on the stability of zinc oxide thin-film transistors

Compared with other materials, zinc oxide (ZnO) exhibits stability in air, high-electron mobility, transparency and low light sensitivity. We investigated these properties in ZnO thin-film transistors (TFTs) containing a cross-linked poly(vinyl alcohol) (C-PVA) (1:3) buffer layer stacked between the semiconductor and gate dielectric. We measured the impact of this C-PVA layer on gate bias stress. We measured the transfer characteristics of the saturation region to determine the threshold voltage and the field-effect mobility of the transistors. We recorded a threshold voltage of 11.53 V in the ZnO TFTs with the C-PVA buffer layer, the field-effect mobility was 0.2 cm2/Vs. There was a positive shift in the threshold voltage of deltaV(TH) approximately 10 V in response to the application of a gate bias stress of 20 V. The positive shift in the threshold voltage was lower than that in pristine ZnO TFTs. This finding suggests that the shift in threshold voltage was due to reduced charge trapping at the semiconductor-gate dielectric interface. Our report indicates that the organic buffer layer enhanced the stability of ZnO TFTs.

Understanding evaporation characteristics of a drop of distilled sulfur mustard (HD) chemical agent from stainless steel and aluminum substrates

We report herein the evaporation rates and mechanism of a drop of distilled sulfur mustard (HD) agent from stainless steel and aluminum substrates. For systematic analysis, we used a laboratory-sized wind tunnel, thermal desorption (TD) connected to gas chromatograph/mass spectrometry (GC/MS) and drop shape analysis (DSA). We found that the evaporation rates of HD from stainless steel and aluminum increased with temperature. The rates were also linearly proportional to drop size. The time-dependent contact angle measurement showed that the evaporation of the drop of HD proceeded only by constant contact area mechanism from stainless steel surface. On the other hand, the evaporation of HD from aluminum proceeded by a combined mechanism of constant contact area mode and constant contact angle mode. Our experimental data sets and analysis could be used to predict vapor and contact hazard persistence of chemical warfare agents (CWAs) in the air and on exterior surfaces with chemical releases, which assists the military decision influencing personnel safety and decontamination of the site upon a chemical attack event.

Analysis of rheumatoid factor according to various hepatitis B virus infectious statuses

OBJECTIVES

Rheumatoid factor (RF) can be seen in hepatitis B virus (HBV) infection. We investigated RF positive rates according to various HBV infectious statuses and vaccination, and the relationship between RF titers and serum HBV DNA levels.

METHODS

We examined 13,670 individuals who visited the Severance Hospital in Seoul, Korea, for a routine health check-up, and obtained serum samples from all individuals.

RESULTS

RF was positive in 3.5% of all subjects, and HBsAg was positive in 4.3%. HBsAg was positive in 21.7% of all RF positive subjects. RF was positive in 17.5% of the HBsAg positive group, while it was positive in 2.9% of the HBsAg negative group (p<0.001). The RF positive rate was increased in positive HBsAg, female sex, and older age. The RF positive rate was lower in those who had anti-HBs after HBV vaccination than in HBsAg positive subjects (2.7% vs. 17.5%, p<0.001). Among the RF positive patients, the RF titer in HBsAg positive patients were higher than that in HBsAg negative patients (159.7±217.1IU/mL vs. 83.0±179.2 IU/mL, p=0.001). The load of HBV DNA may be closely correlated with RF titer in patients with chronic hepatitis B (r=0.508, p=0.005).

CONCLUSIONS

Persistent HBV infection is an important cause for the positive RF in HBV endemic areas. Hepatitis B viral load is associated with RF titer. HBV vaccination may reduce the risk of RF formation.

Abstract P6-05-21: High standardized uptake value of 18F-fluorodeoxy-glucose positron emission tomography is related with FOXM1 expression, which negatively influences survival in breast cancer patients

Background

Standardized uptake value (SUV), which is an indicator reflecting glucose uptake in 18F-fluorodeoxy-glucose positron emission tomography (18FDG-PET), can be implicated to be a prognostic factor in various malignant tumors. Using a data set with gene expression profiling, we tried to uncover a molecular marker associated with a high SUV, along with an exploration its prognostic value in breast cancer.

Methods

Microarray gene expression profiling was performed in 287 breast tumor samples. Five hundred nanograms of total RNA were used for labeling and hybridization, according to the manufacturer's protocols (Illumina, San Diego, CA). In 66 samples with SUV, genes with expression patterns highly correlated with the value of SUV were selected for cluster analysis. Five hundred thirty tree gene features were selected for analysis. Patients were divided into the following two groups: SUV-high cluster and SUV-low cluster. Hierarchical clustering analysis based on 533 gene features. The prognostic value of the identified gene was validated in 287 samples and the online public set.

Results

Gene network analysis using Ingenuity Pathway Analysis software revealed considerable enrichment of the gene network toward FOXM1 in the SUV-high cluster, suggesting that its activation might be a key determinant associated with SUV level. Also, the expression of many marker genes for cell proliferation, such as AURKA, AURKB, BIRC5, BUB1, and TOP2A, was significantly higher in the SUV-high cluster than in the SUV-low cluster. Next, in the 287 patients with known FOXM1 expression levels, the Kaplan-Meier survival analysis revealed a negative prognostic impact of highly expressed FOXM1 for overall survival (OS), disease-free survival (DFS), and distant-metastasis-free survival (DMFS) (P = 0.002, P = 0.015, P = 0.008, respectively; Table 1). To validate a prognostic impact of FOXM1 in an external data, we performed a survival analysis using online gene-expression array data. There was significant correlation between the FOXM1 expression level and OS, DFS and DMFS.

Conclusion

Here we analyzed FOXM1 as a biomarker associated with a high SUV and demonstrated that FOXM1 is a negative prognostic factor in breast cancer.

Prognostic significance of FOXM1 in 287 patients Overall SurvivalBreast cancer-specific survivalDisease-free survivalDistant metastasis-free survivalFOXM1 high (n = 144)log-rank testlog-rank testlog-rank testlog-rank testFOXM1 low (n = 133)P = 0.002P = 0.001P = 0.015P = 0.008

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-05-21.

First Report of Powdery Mildew Caused by Erysiphe platani on Sycamore (Platanus occidentalis) in South Korea

Platanus occidentalis L. (sycamore) is an important shade tree distributed throughout the Northern Hemisphere and in South Korea. It has been widely used as an ornamental tree, especially in urban regions and by roadsides. The average rate of roadside planting throughout South Korea covers about 5.7% (up to 38% in Seoul), equivalent to 0.36 million trees. In early July 2012, after a rainy spell in summer, an outbreak of powdery mildew on sycamore was first observed on roadside trees in Gwangju, a southern province of South Korea. A more extensive nationwide survey revealed no powdery mildew in northern or central regions of South Korea. The disease has spread rapidly within Gwangju, even though fungicide applications were carried out after the rainy spell. Major symptoms included white, superficial mycelia, grey to brown lesions on the surface of the leaves due to the presence of a hyperparasite (tentatively identified as Ampelomyces sp.), a slight chlorosis, and severe leaf distortion followed by defoliation. Conidiophores were produced singly, straight, and unbranched, with lengths of 35.2 to 315.2 μm (average 170.4 μm). Conidia were ellipsoid or doliiform, ranging in size from 34.9 to 47.4 μm (average 38.2 μm) long × 16.5 to 26.8 μm (average 23.9 μm) wide. Primary conidia had a truncate base and rounded apex; secondary conidia had both a truncate base and apex. The conidial outer surface had a reticulated wrinkling. Cleistothecia (i.e., sexual spore structures) were not found during the survey, which extended from July to October. These characteristics and the host species match those of Microsphaera platani (syn. Erysiphe platani), which was described on P. occidentalis in Washington State (2). Fungal rDNA was amplified using primers ITS1 and LR5F (4) for one sample (EML-PLA1, GenBank JX485651). BLASTn searches of GenBank revealed high sequence identity to E. platani (99.5% to JQ365943 and 99.3% to JQ365940). Recently, Liang et al. (3) reported the first occurrence of powdery mildew by E. platani on P. orientalis in China based only on its morphology. Thus, in this study, author could only use ITS sequence data from the United States and Europe to characterize the isolate. To date, nine records of powdery mildews of Platanus spp. have been reported worldwide: on P. hispanica from Brazil, Japan, Hungary, and Slovakia; P. orientalis from Israel; P. racemosa from the United States; P. × acerifolia from the United Kingdom and Germany; and Platanus sp. from Argentina and Australia (1). Interestingly, the hyperparasite, Ampelomyces sp., was found with E. platani, suggesting that there may be some level of biocontrol in nature. Pathogenicity was confirmed by gently pressing diseased leaves onto six leaves of healthy sycamore plants in the field in September. The treated leaves were sealed in sterilized vinyl pack to maintain humid condition for 2 days. Similar symptoms were observed on the inoculated leaves 10 days after inoculation. Koch's postulates were fulfilled by re-observing the fungal pathogen. To our knowledge, this is the first report of powdery mildew caused by E. platani on sycamore in South Korea. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. http://nt.ars-grin.gov/fungaldatabases/ , 2012. (2) D. A. Glawe. Plant Health Progress, doi:10.1094/PHP-2003-0818-01-HN, 2003. (3) C. Liang et al. Plant Pathol. 57:375, 2008. (4) T. J White et al., pp. 315-322 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., ed. Academic Press, New York, 1990.

Developmental expression and subcellular distribution of synaptotagmin 11 in rat hippocampus

Synaptotagmins are required for Ca(2+)-dependent membrane-trafficking in either neuronal synaptic vesicles or cellular membranes. Previous reports suggested that the synaptotagmin 11 (syt11) gene is involved in the development of schizophrenia based on the genomic analysis of patients. Parkin protein binds to the C2 domains of Syt11 which leads to the polyubiquitination of Syt11. However, where and how Syt11 performs its role in the brain is largely unknown. Here, we report that Syt11 is expressed mainly in the brain. In addition, exogenously expressed Syt11 in HEK293 cells can form higher molecular weight complex via its transmembrane domain. Also, Syt11 is targeted to both dendrite and axon compartments. Immunocytochemistry showed that Syt11 is juxtaposed to postsynaptic markers in both excitatory and inhibitory synapses. Both neuroligin 1 and 2, which are postsynaptic cell adhesion molecules and differentially induce excitatory and inhibitory presynapses, respectively, recruit Syt11 in neuron coculture. Immunogold electron microscopy analysis revealed that Syt11 exists mainly in presynaptic neurotransmitter vesicles and plasma membrane, and rarely in postsynaptic sites. These results suggest that Syt11 may contribute to the regulation of neurotransmitter release in the excitatory and inhibitory presynapses, and postsynapse-targeted membrane trafficking in dendrites.

Partial splenic artery embolization for thrombocytopenia and uncontrolled massive ascites after liver transplantation

Thrombocytopenia (platelet < 60,000/mm(3)) and uncontrolled massive ascites (ascitic fluid > 1000 mL/d over 10 days) after liver transplantation (OLT), although uncommon, usually represent serious complications. Splenectomy is a useful treatment despite its many side effects. Recently, partial splenic artery embolization (PSAE) is considered to be a nonsurgical, less invasive treatment. In this study, we retrospectively reviewed the results of PSAE after OLT. Between October 2008 and February 2010, 11 patients underwent PSAE after OLT due to thrombocytopenia (n = 6) or refractory ascites (RA; n = 5). Six patients (54.5%) were males and 3 (27.3%) were children. The primary liver disease was virus-related liver cirrhosis (n = 6), biliary atresia (n = 3), fulminant hepatitis (n = 1), or alcoholic liver cirrhosis (n = 1). Seven grafts were from living and four from deceased donors. The major axial size of spleen was 12.1 to 23.4 cm and its average embolized volume, 76.4% (range = 70%-80%). As the result, the platelet count significantly increased after PSAE in all patients maintaining values greater than 100,000/mm(3) in four thrombocytopenic patients (66.7%). Cases of RA showed marked decreases after PSAE (100%). The follow-up was 6 to 28 months. After PSAE, patients experienced abdominal pain (n = 9, 81.8%), fever (n = 2, 18.2%), and abdominal distension (n = 2, 18.2%). However, there was no serious complication after PSAE such as splenic abscess, rupture, pancreatic infarction, sepsis, or death. In conclusion, PSAE was effective and safe and can be the choice for thrombocytopenia or RA related to hypersplenism after OLT.

Excitation of a nanowire "molecule" in gold-filled photonic crystal fiber

A pair of gold nanowires, incorporated into a photonic crystal fiber, acts as a plasmonic "molecule." Hybridized modes are excited at specific wavelengths by launching light into the glass core. The formation of bonding and antibonding solutions results in a modal splitting of more than 100 nm, even though the spatial separation between the wires is larger than 3 μm. The study provides insight into multiwire plasmonic devices with applications as polarizers or filters in near-field optics, nonlinear plasmonics, optical sensing, and telecommunications.

Profiling of differentially expressed genes in haemophilia A with inhibitor

Inhibitor development is the most significant complication in the therapy of haemophilia A (HA) patients. In spite of many studies, not much is known regarding the mechanism underlying inhibitor development. To understand the mechanism, we analysed profiles of differentially expressed genes (DEGs) between inhibitor and non-inhibitor HA via a microarray technique. Twenty unrelated Korean HAs were studied: 11 were non-inhibitor and nine were HA with inhibitor (≥5 BU mL(-1)). Microarray analysis was conducted using a Human Ref-8 expression Beadchip system (Illumina) and the data were analysed using Beadstudio software. We identified 545 DEGs in inhibitor HA as compared with the non-inhibitor patients; 384 genes were up-regulated and 161 genes were down-regulated. Among them, 75 genes whose expressions were altered by at least two-fold (>+2 or <-2) were selected and classified via the PANTHER classification method. The expressions of signal transduction and immunity-related genes differed significantly in the two groups. For validation of the DEGs, semi-quantitative RT-PCR (semi-qRT-PCR) was conducted with the six selected DEGs. The results corresponded to the microarray data, with the exception of one gene. We also examined the expression of the genes associated with the antigen presentation process via real-time PCR. The average levels of IL10, CTLA4 and TNFα slightly reduced, whereas that of IFNγ increased in the inhibitor HA group. We are currently unable to explain whether this phenomenon is a function of the inhibitor-inducing factor or is an epiphenomenon of antibody production. Nevertheless, our results provide a possible explanation for inhibitor development.

Neurodegeneration of Drosophila drop-dead mutants is associated with hypoxia in the brain

The Drosophila drop-dead (drd) mutant undergoes massive brain degeneration, resulting in sudden death. drd encodes a multi-pass membrane protein possessing nose resistant to fluoxetine (NRF) and putative acyltransferase domains. However, the etiology of brain degeneration that occurs in drd mutant flies is still poorly understood. Herein, we show that drd neurodegeneration may be because of an oxygen deficit in the brain. We found that DRD protein is selectively expressed in cells secreting cuticular and eggshell layers. These layers exhibit blue fluorescence upon UV excitation, which is reduced in drd flies. The drd tracheal air sacs lacking blue fluorescence collapse, which likely contributes to hypoxia. Consistently, genes induced in hypoxia are up-regulated in drd flies. Feeding of anti-reactive oxygen species agents partially rescue the drd from sudden death. We propose that drd flies can provide a non-invasive animal model for hypoxia-induced cell death.

Pressure-assisted melt-filling and optical characterization of Au nano-wires in microstructured fibers

We report a novel splicing-based pressure-assisted melt-filling technique for creating metallic nanowires in hollow channels in microstructured silica fibers. Wires with diameters as small as 120 nm (typical aspect ration 50:1) could be realized at a filling pressure of 300 bar. As an example we investigate a conventional single-mode step-index fiber with a parallel gold nanowire (wire diameter 510 nm) running next to the core. Optical transmission spectra show dips at wavelengths where guided surface plasmon modes on the nanowire phase match to the glass core mode. By monitoring the side-scattered light at narrow breaks in the nanowire, the loss could be estimated. Values as low as 0.7 dB/mm were measured at resonance, corresponding to those of an ultra-long-range eigenmode of the glass-core/nanowire system. By thermal treatment the hollow channel could be collapsed controllably, permitting creation of a conical gold nanowire, the optical properties of which could be monitored by side-scattering. The reproducibility of the technique and the high optical quality of the wires suggest applications in fields such as nonlinear plasmonics, near-field scanning optical microscope tips, cylindrical polarizers, optical sensing and telecommunications.

Optofluidic refractive-index sensor in step-index fiber with parallel hollow micro-channel

We present a simple refractive index sensor based on a step-index fiber with a hollow micro-channel running parallel to its core. This channel becomes waveguiding when filled with a liquid of index greater than silica, causing sharp dips to appear in the transmission spectrum at wavelengths where the glass-core mode phase-matches to a mode of the liquid-core. The sensitivity of the dip-wavelengths to changes in liquid refractive index is quantified and the results used to study the dynamic flow characteristics of fluids in narrow channels. Potential applications of this fiber microstructure include measuring the optical properties of liquids, refractive index sensing, biophotonics and studies of fluid dynamics on the nanoscale.

Frequency of CYP2C9 variant alleles, including CYP2C9*13 in a Korean population and effect on glimepiride pharmacokinetics

WHAT IS KNOWN AND OBJECTIVE

Cytochrome P450 (CYP) 2C9 is a clinically important enzyme involved in the metabolism of many drugs commonly used in humans. Of several allelic variants known to affect the catalytic activity of the CYP2C9 enzyme, the frequencies of the CYP2C9*3 and CYP2C9*13 alleles in the Korean population have been reported as 1·1% and 0·6%, respectively. Our objective was to re-evaluate the frequencies of CYP2C9 allelic variants in the Korean population, including the CYP2C9*13 allele by pyrosequencing, and to investigate the pharmacokinetics of glimepiride in relation to CYP2C9 genotypes, including CYP2C9*3/*3.

METHODS

295 subjects were genotyped for CYP2C9*2 and CYP2C9*3 using the TaqMan procedure, and for CYP2C9*13 using pyrosequencing. These data were combined with our previously reported data to assess the CYP2C9 allele and genotype frequencies in 869 Korean subjects. Data from 24 of the 295 genotyped subjects (22 CYP2C9*1/*1 homozygotes, one CYP2C9*1/*3 heterozygote and one CYP2C9*3/*3 homozygote) who had participated in a bioequivalence study were analysed retrospectively to examine the effects of CYP2C9 genotype on glimepiride pharmacokinetics.

RESULTS

The frequencies of the CYP2C9*1/*3, *3/*3, and *1/*13 genotypes in the study population (n = 295) were 0·081 (n = 24), 0·010 (n = 3) and 0·003 (n = 1), respectively. In the 869 subjects from the combined studies, allele frequencies for CYP2C9*3 and CYP2C9*13 were 0·025 (95% CI: 0·018, 0·033) and 0·002 (95% CI: 0·000, 0·010), respectively. Relative to CYP2C9*1 homozygotes, the one CYP2C9*3 homozygous subject was found to have a higher AUC(0-∞) value (490% of the reference value) and a lower oral clearance rate (18% of the reference).

WHAT IS NEW AND CONCLUSION

This study is the first examination of CYP2C9*3 homozygotes in the Korean population. Our data on the one subject with this genotype suggest that CYP2C9*3/*3 momozygotes have lower clearance of glimepiride and are exposed to higher levels of the drug than wild-type homozygotes. Although we identified a subject with the CYP2C9*13 allele using a new pyrosequencing assay, we were unfortunately unable to investigate its effects on glimepiride pharmacokinetics.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

Association between AMELX polymorphisms and dental caries in Koreans

OBJECTIVES

Dental caries is greatly influenced disease by environmental factors, but recently there are increasing evidences for a genetic component in caries susceptibility. AMELX is the gene coding amelogenin, which is the most important factor for normal enamel development. The aim of this study was to examine the relationship between dental caries and single nucleotide polymorphisms (SNPs) in AMELX.

SUBJECTS AND METHODS

For this study, we used DNA samples collected from 120 unrelated individuals older than 12 years of age. All of them were examined for their oral and dental status under the WHO recommended criteria, and clinical information such as DMFT and DMFS were evaluated. Individuals whose DMFT and DMFS index lower than 2 were designated 'very low caries experience' and higher than 3 were designated 'higher caries experience'. Genomic DNA was extracted from hair samples, and single nucleotide polymorphisms of AMELX were genotyped. Genotyping of three SNPs (rs17878486, rs5933871, rs5934997, intron) in AMELX gene was determined by direct sequencing and analyzed with SNPStats.

RESULTS

There were significant associations between rs5933871 and rs5934997 SNP and caries susceptibility in the water fluoridation group.

CONCLUSIONS

These results suggest that SNPs of AMELX might be associated with dental caries susceptibility in Korean population.

In vitro inhibitory effects of Wen-pi-tang-Hab-Wu-ling-san on human cytochrome P450 isoforms

WHAT IS KNOWN AND OBJECTIVE

Although Wen-pi-tang-Hab-Wu-ling-san (WHW), an oriental herbal medicine, has been prescribed for the treatment of chronic renal failure (CRF) in Korean clinics, no studies regarding WHW-drug interactions had been reported. The purpose of this study was to evaluate the possibility that WHW inhibits the catalytic activities of major cytochrome P450 (CYP) isoforms.

METHODS

The abilities of various WHW extracts to inhibit phenacetin O-de-ethylation (CYP1A2), tolbutamide 4-methylhydroxylation (CYP2C9), omeprazole 4'-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1) and midazolam 1-hydroxylation (CYP3A4) were assessed using human liver microsomes.

RESULTS AND DISCUSSION

WHW extract at concentrations up to 100 μm showed negligible inhibition of the six CYP isoforms tested (CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4), with apparent IC(50) values (concentration of the inhibitor causing 50% inhibition of the original enzyme activity) of 817.5, 601.6, 521.7, 310.2, 342.8 and 487.0 μg/mL, respectively.

WHAT IS NEW AND CONCLUSION

Our in vitro findings suggest that WHW extract at concentrations corresponding to a clinically recommended dosage range has no notable inhibitory effects on CYP isoforms. Therefore, we believe that WHW extract may be free of drug-herb interactions when co-administered with other medicines. However, in vivo human studies are needed to confirm these results.

Plasmon resonances on gold nanowires directly drawn in a step-index fiber

We report the successful production of high-quality gold wires, with diameters down to 260nm, by direct fiber drawing from a gold-filled fused-silica cane. The stack-and-draw technique makes it straightforward to incorporate a conventional step-index core, adjacent to the gold wire, in the cane. In the drawn fiber, strong coupling of light from the glass core to SPP resonances on the gold wire is observed at specific well-defined wavelengths. Such embedded wires have many potential applications, for example, as nanoscale electrodes, in nonlinear optical plasmonics, and as near-field scanning optical microscope tips.