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The disease-resistant OsCK1 (Oryza sativa L. cv. Nakdong) was developed in Korea by inserting a choline kinase (CK1) gene into the rice genome. The key nutrients and anti-nutrients of OsCK1 were analyzed and compared with those of its non-transgenic counterpart and four commercial cultivars grown together at two different locations. The levels of proximates, amino acids, fatty acids, minerals, vitamins, trypsin inhibitors, and phytic acid in OsCK1 were comparable to those of its parent rice and the commercial rice varieties. The results of principal component analysis performed using quantification data from 47 nutritional components revealed differences among the rice samples according to their growing locations rather than by their genotypes. These results confirm that the nutritional quality of rice grains was not affected by the insertion of the CK1 gene and suggest that the quality is more affected by environmental factors such as growing conditions than by genetic factors. [ABSTRACT FROM AUTHOR]

For graphene to be used in semiconductor applications, a 'wide energy gap' of at least 0.5 eV at the Dirac energy must be opened without the introduction of atomic defects. However, such a wide energy gap has not been realized in graphene, except in the cases of narrow, chemically terminated graphene nanostructures with inevitable edge defects. Here, we demonstrated that a wide energy gap of 0.74 eV, which is larger than that of germanium, could be opened in uniform monolayer graphene without the introduction of atomic defects into graphene. The wide energy gap was opened through the adsorption of self-assembled twisted sodium nanostrips. Furthermore, the energy gap was reversibly controllable through the alternate adsorption of sodium and oxygen. The opening of such a wide energy gap with minimal degradation of mobility could improve the applicability of graphene in semiconductor devices, which would result in a major advancement in graphene technology. [ABSTRACT FROM AUTHOR]

This study evaluates the otolith function of patients with head trauma, postulating that otolith dysfunction is a cause of nonspecific dizziness after head trauma. We prospectively enrolled 28 patients referred within 3 months after head trauma between March 2007 and December 2009. Pure tone audiometry, caloric testing and otolith function tests, including cervical vestibular evoked myogenic potential (cVEMP) and subjective visual vertical (SVV) tests, were performed on all patients. The relationship between otolith function and otologic symptoms was analyzed. Of the 28 patients with head trauma, 18 complained of dizziness and 12 experienced hearing loss, including 6 patients who complained of both. On defining otolith dysfunction as an abnormal cVEMP or abnormal SVV, a significant difference in otolith dysfunction existed between the groups with and without dizziness [72 (13/18) vs. 20% (2/10)]. In contrast, no significant difference in otolith dysfunction was detected between the abnormal and normal hearing groups. A significant number of the patients who complained of nonspecific dizziness after trauma had abnormal otolith function. After trauma, when patients complain of dizziness, vestibular function tests, including otolith function tests, should be considered. [ABSTRACT FROM AUTHOR]

Helicobacter pylori infection can induce aberrant CpG island hypermethylation in gastric mucosal epithelial cells. Single nucleotide polymorphisms of proinflammatory cytokine genes encoding for interleukin 1B (IL1B), IL6, and IL8 have been demonstrated to be associated with an increased risk of gastric cancer. To identify the influence of host genetic factors in CpG island hypermethylation induced by H. pylori infection, we analyzed H. pylori-infected chronic gastritis (n = 111) and gastric cancer samples (n = 78) for the methylation status of eight genes previously shown to be hypermethylated in chronic gastritis and single nucleotide polymorphisms of IL1B, IL6, and IL8. The methylation levels were then compared between different genotypes. Gastric cancers from patients with the IL1B-511T/T allele showed significantly higher methylation levels in five genes as compared with gastric cancers from IL1B-511 C carriers (P < 0.05). An increased level of hypermethylation in association with the IL1B-511T/T allele was observed in chronic gastritis samples, but the association was not statistically significant. These findings suggest that the IL1B-511T/T allele is associated with enhanced hypermethylation of multiple CpG island loci, which might contribute to an increase in the risk for gastric cancer in individuals with H. pylori infection and IL1B-511T/T allele. [ABSTRACT FROM AUTHOR]

Gastric carcinoma (GC) is one of the human cancers in which promoter CpG island hypermethylation is frequently found. We used the MethyLight assay to evaluate the methylation status of 16 CpG island loci that are hypermethylated in GC. We analyzed the relationship between CpG island hypermethylation of these 16 genes and the clinicopathological features in 191 advanced GCs. A significant difference was observed between the number of methylated genes in Epstein-Barr virus (EBV)-negative and microsatellite instability (MSI)-negative GCs of different histological types (Lauren classification; P < 0.01). We found that mixed-type (MT) carcinomas, which have both diffuse-type (DT) and intestinal-type (IT) components, had more methylated genes (10.6) than either DT carcinomas (7.6 methylated genes) or IT carcinomas (6.7 methylated genes) (P < 0.001). This trend was also observed when EBV-positive or MSI-positive GCs were excluded from the analysis (9.2, 6.9, and 4.8; P < 0.001). When the IT and DT components were dissected from MT carcinomas and the methylation of these 16 genes was evaluated, both components had a number of methylated genes similar to MT carcinomas, (10.2 and 9.7, respectively), which was significantly higher than was found in IT and DT carcinomas (P < 0.05). These findings indicate that MT carcinoma is distinct from IT and DT carcinomas in its enhanced CpG island hypermethylation status and implicate the enhanced promoter CpG island hypermethylation in the histogenesis of MT carcinoma. [ABSTRACT FROM AUTHOR]

Few studies have compared the clinical and radiographic findings of tuberculomas to those of solitary pulmonary nodules (SPNs) caused by Mycobacterium avium complex (MAC). We retrospectively analyzed clinical and radiographic findings from 26 patients with tuberculomas and 15 patients with SPNs caused by MAC. Median SPN size was 22 mm. In 26 patients (63%), the SPN was detected during a routine health checkup or evaluation of organs other than lungs. Patients with SPNs due to MAC were slightly older (median = 59 years) compared with those with tuberculomas (median = 50 years; P = 0.044). When we compared computed tomography (CT) features between patients with tuberculomas and patients with MAC, no significant differences were found in SPN location or the presence of calcification, cavitation, central low attenuation, and the satellite lesions. Although the maximum standardized uptake values were slightly higher in patients with SPNs due to MAC (median = 8.5) compared with those with tuberculomas (median = 2.2), this difference was not significant ( P = 0.053). Of the 15 patients with SPNs due to MAC, 10 were initially diagnosed with “tuberculoma” and administered antituberculosis medication. MAC pulmonary disease should be considered in the differential diagnosis of SPNs, even when encountered in geographic regions with a high prevalence of pulmonary tuberculosis. [ABSTRACT FROM AUTHOR]

Hypoplastic left heart syndrome (HLHS) is rare but serious. It is the most common cause of death from heart disease during the first week of life. With surgical repair or a heart transplant, about 70% of children born with HLHS live for at least 5 years. The purpose of this study is to achieve an optimization of the systemic-topulmonary artery shunt. In this study, computational fluid dynamic (CFD) models were used to determine the velocity profile in a systemic-to-pulmonary artery shunt and we suggest a simplified method of calculating the blood mass flow rate in the shunt based on ultrasound systems. We analyzed the flow characteristic variations and Oscillatory Shear Index (OSI) due to the anastomosis angle and changing shunt diameter. [ABSTRACT FROM AUTHOR]

This study examined the association between markers in transforming growth factor alpha ( TGFA) and isolated, non-syndromic cleft lip with/without palate (CL/P) using a case–parent trio design, considering parent-of-origin effects. We also tested for gene–environmental interaction with common maternal exposures, and for gene–gene interaction using markers in TGFA and another recognized causal gene, IRF6. CL/P case–parent trios from four populations (76 from Maryland, 146 from Taiwan, 35 from Singapore, and 40 from Korea) were genotyped for 17 single nucleotide polymorphisms (SNPs) in TGFA. The transmission disequilibrium test was used to test individual SNPs, and the parent-of-origin likelihood ratio test (PO-LRT) was used to assess parent-of-origin effects. We also screened for possible gene–environment interaction using PBAT, and tested for gene–gene interaction using conditional logistic regression models. When all trios were combined, four SNPs showed significant excess maternal transmission, two of which gave significant PO-LRT values [rs3821261: P = 0.004 and OR(imprinting) = 4.17; and rs3771475: P = 0.027 and OR(imprinting) = 2.44]. Haplotype analysis of these two SNPS also supported excess maternal transmission. We saw intriguing but suggestive evidence of G × E interaction for several SNPs in TGFA when either individual SNPs or haplotypes of adjacent SNPs were considered. Thus, TGFA appears to influence risk of CL/P through unconventional means with an apparent parent-of-origin effect (excess maternal transmission) and possible interaction with maternal exposures. [ABSTRACT FROM AUTHOR]

Isolated cleft lip with or without cleft palate (CL/P) is among the most common human birth defects, with a prevalence of 1 in 700 live births. The paired box (PAX) genes have been suggested as candidate genes for CL/P based largely on mouse models; however, few human studies have focused on this gene family. This study tests for association between markers in four PAX genes and CL/P using a case-parent trio design considering parent-of-origin effects. Trios from four populations (76 from Maryland, 146 from Taiwan, 35 from Singapore, and 40 from Korea) were genotyped for 34 single nucleotide polymorphisms (SNPs) in the PAX3, PAX6, PAX7, and PAX9 genes. We performed the transmission disequilibrium test (TDT) on individual SNPs. Parent-of-origin effects were assessed using the transmission asymmetry test (TAT) and the parent-of-origin likelihood ratio test (PO-LRT). TDT analysis showed one SNP (rs766325) in PAX7 yielding evidence of linkage and association when parent-of-origin was not considered, with an OR(transmission)=1.62 (P=0.003), and five SNPs in PAX6 (including two pairs in near perfect linkage disequilibrium). TAT analysis of all trios revealed two SNPs in PAX7 and four SNPs in PAX3 showing significant excess maternal transmission. For these six SNPs, the maternal OR(transmission) ranged between 1.74 and 2.40, and PO-LRT was also significant (P-values=0.035–0.012). When this analysis was limited to trios with male cases, SNPs in PAX7 showed higher maternal OR(transmission) and greater significance. PAX genes may influence the risk of CL/P through maternal effects, possibly imprinting, which seems to be stronger among male cases.European Journal of Human Genetics (2009) 17, 831–839; doi:10.1038/ejhg.2008.250; published online 14 January 2009 [ABSTRACT FROM AUTHOR]

Helicobacter pylori infection can induce CpG island (CGI) hypermethylation in gastric mucosa. Recently, genes occupied by Polycomb proteins in embryonic stem cells were shown to be vulnerable to aberrant DNA hypermethylation in cancers. To explore the relationship between H. pylori infection and DNA methylation changes in neoplastic and non-neoplastic stomach, we analyzed 25 CGIs and repetitive DNA elements from 82 chronic gastritis and 69 gastric carcinomas. Twenty-three CGIs showed significantly higher methylation levels in H. pylori-negative gastric carcinoma (n = 28) than in H. pylori-negative chronic gastritis (n = 39; P < 0.05), indicating cancer-associated methylation. Eight CGIs exhibited significantly higher methylation levels in H. pylori-positive chronic gastritis (n = 43) than in H. pylori-negative chronic gastritis (n = 39; P < 0.05). Six CGIs showed both cancer-associated and H. pylori-associated hypermethylation. Six (75%) of the eight H. pylori-associated hypermethylated genes contained at least one of three repressive marks (Suzl2 occupancy, Eed occupancy, histone H3 K27 trimethylation), whereas 31% of the remaining cancer-associated hypermethylated genes had at least one mark. The findings suggest that H. pylori infection strongly induces CGI hypermethylation in gastric epithelial cells and that susceptibility to H. pylori-induced DNA hypermethylation may be determined by Polycomb repressive marks in stem or progenitor cells. [ABSTRACT FROM AUTHOR]

We describe a DNA microarray system using a bipolar integrated circuit photodiode array (PDA) chip as a new platform for DNA analysis. The PDA chip comprises an 8 × 6 array of photodiodes each with a diameter of 600 μm. Each photodiode element acts both as a support for an immobilizing probe DNA and as a two-dimensional photodetector. The usefulness of the PDA microarray platform is demonstrated by the detection of high-risk subtypes of human papilloma virus (HPV). The polymerase chain reaction (PCR)-amplified biotinylated HPV target DNA was hybridized with the immobilized probe DNA on the photodiode surface, and the chip was incubated in an anti-biotin antibody-conjugated gold nanoparticle solution. The silver enhancement by the gold nanoparticles bound to the biotin of the HPV target DNA precipitates silver metal particles at the chip surfaces, which block light irradiated from above. The resulting drop in output voltage depends on the amount of target DNA present in the sample solution, which allows the specific detection and the quantitative analysis of the complementary target DNA. The PDA chip showed high relative signal ratios of HPV probe DNA hybridized with complementary target DNA, indicating an excellent capability in discriminating HPV subtypes. The detection limit for the HPV target DNA analysis improved from 1.2 nM to 30 pM by changing the silver development time from 5 to 10 min. Moreover, the enhanced silver development promoted by the gold nanoparticles could be applied to a broader range of target DNA concentration by controlling the silver development time. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We present the Monte Carlo simulation of submonolayer film growth during molecular beam epitaxy (MBE) at low temperature. We have made systematic study to see how the parameters diffusion to flux ratio (D/F), diffusional anisotropy (DA) and sticking anisotropy influences on island density exponent (χ), size distribution and scaling behaviour. We have found that, as diffusional anisotropy changes from DA = 1 to DA = ∝, the density exponent changes from χ = 0.34 ± 0.01 to 0.28 ± 0.01 for isotropic sticking case but when sticking is anisotropic the density exponent changes from χ = 0.31 ± 0.01 to 0.24 ± 0.01. The influence produced by DA on island size distribution is observed to depend on D/F ratio and sticking anisotropy. Depending on DA values and D/F ratio, the size distribution is also observed to be insensitive to the change in diffusional anisotropy. We also study the influence of diffusional anisotropy on scaling function for two sticking anisotropy condition. The scaling behaviour of island size distribution is observed to be not affected by all diffusional anisotropy as well as sticking anisotropy condition. [ABSTRACT FROM AUTHOR]

Cr-based chalcogenide spinels, which do not have heterovalency and distortion-induced ions such as manganese oxides with perovskite structure, have demonstrated the existence of colossal magnetoresistance. In order to investigate the magnetotransport phenomena and magnetic properties of sulfospinels Zn x Fe1− x Cr2S4, polycrystalline Zn x Fe1− x Cr2S4 samples were synthesized in the 0 ≤ x ≤ 0.2 range by a solid reaction method. The crystal structure for x = 0.05, 0.1, and 0.2 turned out to be cubic at room temperature by X-ray diffraction measurement. In magnetoresistance measurement, Zn x Fe1− x Cr2S4 samples indicate that this system is semiconducting below about 150 K. The temperature of maximum magnetoresistance is almost consistent with Curie temperature. The isomer shift and the electric quadrupole shift of Zn x Fe1− x Cr2S4 samples by Mössbauer experiment show that Fe2+ ions occupy the tetrahedral site in the spinel structure. As the Zn ions are substituted for Fe ions, the Jahn–Teller relaxation slows down and the electric quadrupole shift increases. The magnetotransport phenomena of Zn x Fe1− x Cr2S4 is related to Jahn–Teller effect and half-metallic electronic structure, which are different from the double exchange interactions of the manganite La–Ca–Mn–O system or the triple exchange interactions of sulfospinel Cu x Fe1− x Cr2S4. [ABSTRACT FROM AUTHOR]

Structural transformation and the related variation in magnetic and optical properties of Co3− x Fe x O4 thin films grown by a sol–gel method have been investigated as the Fe composition varies up to x = 2. The normal spinel phase is dominant below x = 0.55 and the inverse spinel phase grows as x increases further. Conversion electron Mössbauer spectroscopy (CEMS) measurements indicate that the normal spinel phase have octahedral Fe3+ ions mostly while the inverse spinel phase contain octahedral Fe2+ and tetrahedral Fe3+ ions. For higher Fe composition ( x > 1.22), Co2+ ions are found to substitute the octahedral Fe2+ sites. The measured optical absorption spectra for the Co3− x Fe x O4 films by spectroscopic ellipsometry support the CEMS interpretation. [ABSTRACT FROM AUTHOR]

Cr-based chalcogenide spinels, which do not have heterovalency and distortion-induced ions such as manganese oxides with perovskite structure, have demonstrated the existence of colossal magnetoresistance. In order to investigate the magnetotransport phenomena and magnetic properties of sulfospinels Zn x Fe1− x Cr2S4, polycrystalline Zn x Fe1− x Cr2S4 samples were synthesized in the 0 ≤ x ≤ 0.2 range by a solid reaction method. The crystal structure for x = 0.05, 0.1, and 0.2 turned out to be cubic at room temperature by X-ray diffraction measurement. In magnetoresistance measurement, Zn x Fe1− x Cr2S4 samples indicate that this system is semiconducting below about 150 K. The temperature of maximum magnetoresistance is almost consistent with Curie temperature. The isomer shift and the electric quadrupole shift of Zn x Fe1− x Cr2S4 samples by Mössbauer experiment show that Fe2+ ions occupy the tetrahedral site in the spinel structure. As the Zn ions are substituted for Fe ions, the Jahn–Teller relaxation slows down and the electric quadrupole shift increases. The magnetotransport phenomena of Zn x Fe1− x Cr2S4 is related to Jahn–Teller effect and half-metallic electronic structure, which are different from the double exchange interactions of the manganite La–Ca–Mn–O system or the triple exchange interactions of sulfospinel Cu x Fe1− x Cr2S4. [ABSTRACT FROM AUTHOR]

Summary Gold nanoparticles modified with poly(2?methyl?2?oxazoline) have been prepared via chemical reduction of HAuCl 4 by NaBH 4. The gold nanoparticles were homogeneously dispersed in poly(vinyl chloride) as a polymer matrix by the miscibility between the protecting polymer of the nanoparticle and the polymer matrix. Differential scanning calorimetry and UV?vis absorption measurement clearly showed that the miscibility played an important role for incorporation of the metal nanoparticles in the polymer matrix. [ABSTRACT FROM AUTHOR]